diff options
Diffstat (limited to 'fs/ocfs2/dlm')
| -rw-r--r-- | fs/ocfs2/dlm/Makefile | 6 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmapi.h | 214 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmast.c | 466 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmcommon.h | 884 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmconvert.c | 530 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmconvert.h | 35 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmdebug.c | 246 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmdebug.h | 30 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmdomain.c | 1469 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmdomain.h | 36 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmlock.c | 676 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmmaster.c | 2666 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmrecovery.c | 2132 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmthread.c | 695 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmunlock.c | 672 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmver.c | 42 | ||||
| -rw-r--r-- | fs/ocfs2/dlm/dlmver.h | 31 |
17 files changed, 10830 insertions, 0 deletions
diff --git a/fs/ocfs2/dlm/Makefile b/fs/ocfs2/dlm/Makefile new file mode 100644 index 0000000..2a5274b --- /dev/null +++ b/fs/ocfs2/dlm/Makefile @@ -0,0 +1,6 @@ +EXTRA_CFLAGS += -Ifs/ocfs2 + +obj-$(CONFIG_OCFS2_FS) += ocfs2_dlm.o + +ocfs2_dlm-objs := dlmdomain.o dlmdebug.o dlmthread.o dlmrecovery.o \ + dlmmaster.o dlmast.o dlmconvert.o dlmlock.o dlmunlock.o dlmver.o diff --git a/fs/ocfs2/dlm/dlmapi.h b/fs/ocfs2/dlm/dlmapi.h new file mode 100644 index 0000000..53652f5 --- /dev/null +++ b/fs/ocfs2/dlm/dlmapi.h @@ -0,0 +1,214 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmapi.h + * + * externally exported dlm interfaces + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + +#ifndef DLMAPI_H +#define DLMAPI_H + +struct dlm_lock; +struct dlm_ctxt; + +/* NOTE: changes made to this enum should be reflected in dlmdebug.c */ +enum dlm_status { + DLM_NORMAL = 0, /* 0: request in progress */ + DLM_GRANTED, /* 1: request granted */ + DLM_DENIED, /* 2: request denied */ + DLM_DENIED_NOLOCKS, /* 3: request denied, out of system resources */ + DLM_WORKING, /* 4: async request in progress */ + DLM_BLOCKED, /* 5: lock request blocked */ + DLM_BLOCKED_ORPHAN, /* 6: lock request blocked by a orphan lock*/ + DLM_DENIED_GRACE_PERIOD, /* 7: topological change in progress */ + DLM_SYSERR, /* 8: system error */ + DLM_NOSUPPORT, /* 9: unsupported */ + DLM_CANCELGRANT, /* 10: can't cancel convert: already granted */ + DLM_IVLOCKID, /* 11: bad lockid */ + DLM_SYNC, /* 12: synchronous request granted */ + DLM_BADTYPE, /* 13: bad resource type */ + DLM_BADRESOURCE, /* 14: bad resource handle */ + DLM_MAXHANDLES, /* 15: no more resource handles */ + DLM_NOCLINFO, /* 16: can't contact cluster manager */ + DLM_NOLOCKMGR, /* 17: can't contact lock manager */ + DLM_NOPURGED, /* 18: can't contact purge daemon */ + DLM_BADARGS, /* 19: bad api args */ + DLM_VOID, /* 20: no status */ + DLM_NOTQUEUED, /* 21: NOQUEUE was specified and request failed */ + DLM_IVBUFLEN, /* 22: invalid resource name length */ + DLM_CVTUNGRANT, /* 23: attempted to convert ungranted lock */ + DLM_BADPARAM, /* 24: invalid lock mode specified */ + DLM_VALNOTVALID, /* 25: value block has been invalidated */ + DLM_REJECTED, /* 26: request rejected, unrecognized client */ + DLM_ABORT, /* 27: blocked lock request cancelled */ + DLM_CANCEL, /* 28: conversion request cancelled */ + DLM_IVRESHANDLE, /* 29: invalid resource handle */ + DLM_DEADLOCK, /* 30: deadlock recovery refused this request */ + DLM_DENIED_NOASTS, /* 31: failed to allocate AST */ + DLM_FORWARD, /* 32: request must wait for primary's response */ + DLM_TIMEOUT, /* 33: timeout value for lock has expired */ + DLM_IVGROUPID, /* 34: invalid group specification */ + DLM_VERS_CONFLICT, /* 35: version conflicts prevent request handling */ + DLM_BAD_DEVICE_PATH, /* 36: Locks device does not exist or path wrong */ + DLM_NO_DEVICE_PERMISSION, /* 37: Client has insufficient pers for device */ + DLM_NO_CONTROL_DEVICE, /* 38: Cannot set options on opened device */ + + DLM_RECOVERING, /* 39: extension, allows caller to fail a lock + request if it is being recovered */ + DLM_MIGRATING, /* 40: extension, allows caller to fail a lock + request if it is being migrated */ + DLM_MAXSTATS, /* 41: upper limit for return code validation */ +}; + +/* for pretty-printing dlm_status error messages */ +const char *dlm_errmsg(enum dlm_status err); +/* for pretty-printing dlm_status error names */ +const char *dlm_errname(enum dlm_status err); + +/* Eventually the DLM will use standard errno values, but in the + * meantime this lets us track dlm errors as they bubble up. When we + * bring its error reporting into line with the rest of the stack, + * these can just be replaced with calls to mlog_errno. */ +#define dlm_error(st) do { \ + if ((st) != DLM_RECOVERING && \ + (st) != DLM_MIGRATING && \ + (st) != DLM_FORWARD) \ + mlog(ML_ERROR, "dlm status = %s\n", dlm_errname((st))); \ +} while (0) + +#define DLM_LKSB_UNUSED1 0x01 +#define DLM_LKSB_PUT_LVB 0x02 +#define DLM_LKSB_GET_LVB 0x04 +#define DLM_LKSB_UNUSED2 0x08 +#define DLM_LKSB_UNUSED3 0x10 +#define DLM_LKSB_UNUSED4 0x20 +#define DLM_LKSB_UNUSED5 0x40 +#define DLM_LKSB_UNUSED6 0x80 + +#define DLM_LVB_LEN 64 + +/* Callers are only allowed access to the lvb and status members of + * this struct. */ +struct dlm_lockstatus { + enum dlm_status status; + u32 flags; + struct dlm_lock *lockid; + char lvb[DLM_LVB_LEN]; +}; + +/* Valid lock modes. */ +#define LKM_IVMODE (-1) /* invalid mode */ +#define LKM_NLMODE 0 /* null lock */ +#define LKM_CRMODE 1 /* concurrent read unsupported */ +#define LKM_CWMODE 2 /* concurrent write unsupported */ +#define LKM_PRMODE 3 /* protected read */ +#define LKM_PWMODE 4 /* protected write unsupported */ +#define LKM_EXMODE 5 /* exclusive */ +#define LKM_MAXMODE 5 +#define LKM_MODEMASK 0xff + +/* Flags passed to dlmlock and dlmunlock: + * reserved: flags used by the "real" dlm + * only a few are supported by this dlm + * (U) = unsupported by ocfs2 dlm */ +#define LKM_ORPHAN 0x00000010 /* this lock is orphanable (U) */ +#define LKM_PARENTABLE 0x00000020 /* this lock was orphaned (U) */ +#define LKM_BLOCK 0x00000040 /* blocking lock request (U) */ +#define LKM_LOCAL 0x00000080 /* local lock request */ +#define LKM_VALBLK 0x00000100 /* lock value block request */ +#define LKM_NOQUEUE 0x00000200 /* non blocking request */ +#define LKM_CONVERT 0x00000400 /* conversion request */ +#define LKM_NODLCKWT 0x00000800 /* this lock wont deadlock (U) */ +#define LKM_UNLOCK 0x00001000 /* deallocate this lock */ +#define LKM_CANCEL 0x00002000 /* cancel conversion request */ +#define LKM_DEQALL 0x00004000 /* remove all locks held by proc (U) */ +#define LKM_INVVALBLK 0x00008000 /* invalidate lock value block */ +#define LKM_SYNCSTS 0x00010000 /* return synchronous status if poss (U) */ +#define LKM_TIMEOUT 0x00020000 /* lock request contains timeout (U) */ +#define LKM_SNGLDLCK 0x00040000 /* request can self-deadlock (U) */ +#define LKM_FINDLOCAL 0x00080000 /* find local lock request (U) */ +#define LKM_PROC_OWNED 0x00100000 /* owned by process, not group (U) */ +#define LKM_XID 0x00200000 /* use transaction id for deadlock (U) */ +#define LKM_XID_CONFLICT 0x00400000 /* do not allow lock inheritance (U) */ +#define LKM_FORCE 0x00800000 /* force unlock flag */ +#define LKM_REVVALBLK 0x01000000 /* temporary solution: re-validate + lock value block (U) */ +/* unused */ +#define LKM_UNUSED1 0x00000001 /* unused */ +#define LKM_UNUSED2 0x00000002 /* unused */ +#define LKM_UNUSED3 0x00000004 /* unused */ +#define LKM_UNUSED4 0x00000008 /* unused */ +#define LKM_UNUSED5 0x02000000 /* unused */ +#define LKM_UNUSED6 0x04000000 /* unused */ +#define LKM_UNUSED7 0x08000000 /* unused */ + +/* ocfs2 extensions: internal only + * should never be used by caller */ +#define LKM_MIGRATION 0x10000000 /* extension: lockres is to be migrated + to another node */ +#define LKM_PUT_LVB 0x20000000 /* extension: lvb is being passed + should be applied to lockres */ +#define LKM_GET_LVB 0x40000000 /* extension: lvb should be copied + from lockres when lock is granted */ +#define LKM_RECOVERY 0x80000000 /* extension: flag for recovery lock + used to avoid recovery rwsem */ + + +typedef void (dlm_astlockfunc_t)(void *); +typedef void (dlm_bastlockfunc_t)(void *, int); +typedef void (dlm_astunlockfunc_t)(void *, enum dlm_status); + +enum dlm_status dlmlock(struct dlm_ctxt *dlm, + int mode, + struct dlm_lockstatus *lksb, + int flags, + const char *name, + dlm_astlockfunc_t *ast, + void *data, + dlm_bastlockfunc_t *bast); + +enum dlm_status dlmunlock(struct dlm_ctxt *dlm, + struct dlm_lockstatus *lksb, + int flags, + dlm_astunlockfunc_t *unlockast, + void *data); + +struct dlm_ctxt * dlm_register_domain(const char *domain, u32 key); + +void dlm_unregister_domain(struct dlm_ctxt *dlm); + +void dlm_print_one_lock(struct dlm_lock *lockid); + +typedef void (dlm_eviction_func)(int, void *); +struct dlm_eviction_cb { + struct list_head ec_item; + dlm_eviction_func *ec_func; + void *ec_data; +}; +void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb, + dlm_eviction_func *f, + void *data); +void dlm_register_eviction_cb(struct dlm_ctxt *dlm, + struct dlm_eviction_cb *cb); +void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb); + +#endif /* DLMAPI_H */ diff --git a/fs/ocfs2/dlm/dlmast.c b/fs/ocfs2/dlm/dlmast.c new file mode 100644 index 0000000..8d17d28 --- /dev/null +++ b/fs/ocfs2/dlm/dlmast.c @@ -0,0 +1,466 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmast.c + * + * AST and BAST functionality for local and remote nodes + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + + +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/highmem.h> +#include <linux/utsname.h> +#include <linux/init.h> +#include <linux/sysctl.h> +#include <linux/random.h> +#include <linux/blkdev.h> +#include <linux/socket.h> +#include <linux/inet.h> +#include <linux/spinlock.h> + + +#include "cluster/heartbeat.h" +#include "cluster/nodemanager.h" +#include "cluster/tcp.h" +#include "cluster/endian.h" + +#include "dlmapi.h" +#include "dlmcommon.h" + +#define MLOG_MASK_PREFIX ML_DLM +#include "cluster/masklog.h" + +static void dlm_update_lvb(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_lock *lock); +static int dlm_should_cancel_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock); + +/* Should be called as an ast gets queued to see if the new + * lock level will obsolete a pending bast. + * For example, if dlm_thread queued a bast for an EX lock that + * was blocking another EX, but before sending the bast the + * lock owner downconverted to NL, the bast is now obsolete. + * Only the ast should be sent. + * This is needed because the lock and convert paths can queue + * asts out-of-band (not waiting for dlm_thread) in order to + * allow for LKM_NOQUEUE to get immediate responses. */ +static int dlm_should_cancel_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock) +{ + assert_spin_locked(&dlm->ast_lock); + assert_spin_locked(&lock->spinlock); + + if (lock->ml.highest_blocked == LKM_IVMODE) + return 0; + BUG_ON(lock->ml.highest_blocked == LKM_NLMODE); + + if (lock->bast_pending && + list_empty(&lock->bast_list)) + /* old bast already sent, ok */ + return 0; + + if (lock->ml.type == LKM_EXMODE) + /* EX blocks anything left, any bast still valid */ + return 0; + else if (lock->ml.type == LKM_NLMODE) + /* NL blocks nothing, no reason to send any bast, cancel it */ + return 1; + else if (lock->ml.highest_blocked != LKM_EXMODE) + /* PR only blocks EX */ + return 1; + + return 0; +} + +static void __dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock) +{ + mlog_entry_void(); + + BUG_ON(!dlm); + BUG_ON(!lock); + + assert_spin_locked(&dlm->ast_lock); + if (!list_empty(&lock->ast_list)) { + mlog(ML_ERROR, "ast list not empty!! pending=%d, newlevel=%d\n", + lock->ast_pending, lock->ml.type); + BUG(); + } + BUG_ON(!list_empty(&lock->ast_list)); + if (lock->ast_pending) + mlog(0, "lock has an ast getting flushed right now\n"); + + /* putting lock on list, add a ref */ + dlm_lock_get(lock); + spin_lock(&lock->spinlock); + + /* check to see if this ast obsoletes the bast */ + if (dlm_should_cancel_bast(dlm, lock)) { + struct dlm_lock_resource *res = lock->lockres; + mlog(0, "%s: cancelling bast for %.*s\n", + dlm->name, res->lockname.len, res->lockname.name); + lock->bast_pending = 0; + list_del_init(&lock->bast_list); + lock->ml.highest_blocked = LKM_IVMODE; + /* removing lock from list, remove a ref. guaranteed + * this won't be the last ref because of the get above, + * so res->spinlock will not be taken here */ + dlm_lock_put(lock); + /* free up the reserved bast that we are cancelling. + * guaranteed that this will not be the last reserved + * ast because *both* an ast and a bast were reserved + * to get to this point. the res->spinlock will not be + * taken here */ + dlm_lockres_release_ast(dlm, res); + } + list_add_tail(&lock->ast_list, &dlm->pending_asts); + lock->ast_pending = 1; + spin_unlock(&lock->spinlock); +} + +void dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock) +{ + mlog_entry_void(); + + BUG_ON(!dlm); + BUG_ON(!lock); + + spin_lock(&dlm->ast_lock); + __dlm_queue_ast(dlm, lock); + spin_unlock(&dlm->ast_lock); +} + + +static void __dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock) +{ + mlog_entry_void(); + + BUG_ON(!dlm); + BUG_ON(!lock); + assert_spin_locked(&dlm->ast_lock); + + BUG_ON(!list_empty(&lock->bast_list)); + if (lock->bast_pending) + mlog(0, "lock has a bast getting flushed right now\n"); + + /* putting lock on list, add a ref */ + dlm_lock_get(lock); + spin_lock(&lock->spinlock); + list_add_tail(&lock->bast_list, &dlm->pending_basts); + lock->bast_pending = 1; + spin_unlock(&lock->spinlock); +} + +void dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock) +{ + mlog_entry_void(); + + BUG_ON(!dlm); + BUG_ON(!lock); + + spin_lock(&dlm->ast_lock); + __dlm_queue_bast(dlm, lock); + spin_unlock(&dlm->ast_lock); +} + +static void dlm_update_lvb(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_lock *lock) +{ + struct dlm_lockstatus *lksb = lock->lksb; + BUG_ON(!lksb); + + /* only updates if this node masters the lockres */ + if (res->owner == dlm->node_num) { + + spin_lock(&res->spinlock); + /* check the lksb flags for the direction */ + if (lksb->flags & DLM_LKSB_GET_LVB) { + mlog(0, "getting lvb from lockres for %s node\n", + lock->ml.node == dlm->node_num ? "master" : + "remote"); + memcpy(lksb->lvb, res->lvb, DLM_LVB_LEN); + } else if (lksb->flags & DLM_LKSB_PUT_LVB) { + mlog(0, "setting lvb from lockres for %s node\n", + lock->ml.node == dlm->node_num ? "master" : + "remote"); + memcpy(res->lvb, lksb->lvb, DLM_LVB_LEN); + } + spin_unlock(&res->spinlock); + } + + /* reset any lvb flags on the lksb */ + lksb->flags &= ~(DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB); +} + +void dlm_do_local_ast(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_lock *lock) +{ + dlm_astlockfunc_t *fn; + struct dlm_lockstatus *lksb; + + mlog_entry_void(); + + lksb = lock->lksb; + fn = lock->ast; + BUG_ON(lock->ml.node != dlm->node_num); + + dlm_update_lvb(dlm, res, lock); + (*fn)(lock->astdata); +} + + +int dlm_do_remote_ast(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_lock *lock) +{ + int ret; + struct dlm_lockstatus *lksb; + int lksbflags; + + mlog_entry_void(); + + lksb = lock->lksb; + BUG_ON(lock->ml.node == dlm->node_num); + + lksbflags = lksb->flags; + dlm_update_lvb(dlm, res, lock); + + /* lock request came from another node + * go do the ast over there */ + ret = dlm_send_proxy_ast(dlm, res, lock, lksbflags); + return ret; +} + +void dlm_do_local_bast(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_lock *lock, int blocked_type) +{ + dlm_bastlockfunc_t *fn = lock->bast; + + mlog_entry_void(); + BUG_ON(lock->ml.node != dlm->node_num); + + (*fn)(lock->astdata, blocked_type); +} + + + +int dlm_proxy_ast_handler(struct o2net_msg *msg, u32 len, void *data) +{ + int ret; + unsigned int locklen; + struct dlm_ctxt *dlm = data; + struct dlm_lock_resource *res = NULL; + struct dlm_lock *lock = NULL; + struct dlm_proxy_ast *past = (struct dlm_proxy_ast *) msg->buf; + char *name; + struct list_head *iter, *head=NULL; + u64 cookie; + u32 flags; + + if (!dlm_grab(dlm)) { + dlm_error(DLM_REJECTED); + return DLM_REJECTED; + } + + mlog_bug_on_msg(!dlm_domain_fully_joined(dlm), + "Domain %s not fully joined!\n", dlm->name); + + name = past->name; + locklen = past->namelen; + cookie = be64_to_cpu(past->cookie); + flags = be32_to_cpu(past->flags); + + if (locklen > DLM_LOCKID_NAME_MAX) { + ret = DLM_IVBUFLEN; + mlog(ML_ERROR, "Invalid name length in proxy ast handler!\n"); + goto leave; + } + + if ((flags & (LKM_PUT_LVB|LKM_GET_LVB)) == + (LKM_PUT_LVB|LKM_GET_LVB)) { + mlog(ML_ERROR, "both PUT and GET lvb specified\n"); + ret = DLM_BADARGS; + goto leave; + } + + mlog(0, "lvb: %s\n", flags & LKM_PUT_LVB ? "put lvb" : + (flags & LKM_GET_LVB ? "get lvb" : "none")); + + mlog(0, "type=%d, blocked_type=%d\n", past->type, past->blocked_type); + + if (past->type != DLM_AST && + past->type != DLM_BAST) { + mlog(ML_ERROR, "Unknown ast type! %d, cookie=%"MLFu64", " + "name=%.*s\n", past->type, cookie, locklen, name); + ret = DLM_IVLOCKID; + goto leave; + } + + res = dlm_lookup_lockres(dlm, name, locklen); + if (!res) { + mlog(ML_ERROR, "got %sast for unknown lockres! " + "cookie=%"MLFu64", name=%.*s, namelen=%u\n", + past->type == DLM_AST ? "" : "b", + cookie, locklen, name, locklen); + ret = DLM_IVLOCKID; + goto leave; + } + + /* cannot get a proxy ast message if this node owns it */ + BUG_ON(res->owner == dlm->node_num); + + mlog(0, "lockres %.*s\n", res->lockname.len, res->lockname.name); + + spin_lock(&res->spinlock); + if (res->state & DLM_LOCK_RES_RECOVERING) { + mlog(0, "responding with DLM_RECOVERING!\n"); + ret = DLM_RECOVERING; + goto unlock_out; + } + if (res->state & DLM_LOCK_RES_MIGRATING) { + mlog(0, "responding with DLM_MIGRATING!\n"); + ret = DLM_MIGRATING; + goto unlock_out; + } + /* try convert queue for both ast/bast */ + head = &res->converting; + lock = NULL; + list_for_each(iter, head) { + lock = list_entry (iter, struct dlm_lock, list); + if (be64_to_cpu(lock->ml.cookie) == cookie) + goto do_ast; + } + + /* if not on convert, try blocked for ast, granted for bast */ + if (past->type == DLM_AST) + head = &res->blocked; + else + head = &res->granted; + + list_for_each(iter, head) { + lock = list_entry (iter, struct dlm_lock, list); + if (be64_to_cpu(lock->ml.cookie) == cookie) + goto do_ast; + } + + mlog(ML_ERROR, "got %sast for unknown lock! cookie=%"MLFu64", " + "name=%.*s, namelen=%u\n", + past->type == DLM_AST ? "" : "b", cookie, locklen, name, locklen); + + ret = DLM_NORMAL; +unlock_out: + spin_unlock(&res->spinlock); + goto leave; + +do_ast: + ret = DLM_NORMAL; + if (past->type == DLM_AST) { + /* do not alter lock refcount. switching lists. */ + list_del_init(&lock->list); + list_add_tail(&lock->list, &res->granted); + mlog(0, "ast: adding to granted list... type=%d, " + "convert_type=%d\n", lock->ml.type, lock->ml.convert_type); + if (lock->ml.convert_type != LKM_IVMODE) { + lock->ml.type = lock->ml.convert_type; + lock->ml.convert_type = LKM_IVMODE; + } else { + // should already be there.... + } + + lock->lksb->status = DLM_NORMAL; + + /* if we requested the lvb, fetch it into our lksb now */ + if (flags & LKM_GET_LVB) { + BUG_ON(!(lock->lksb->flags & DLM_LKSB_GET_LVB)); + memcpy(lock->lksb->lvb, past->lvb, DLM_LVB_LEN); + } + } + spin_unlock(&res->spinlock); + + if (past->type == DLM_AST) + dlm_do_local_ast(dlm, res, lock); + else + dlm_do_local_bast(dlm, res, lock, past->blocked_type); + +leave: + + if (res) + dlm_lockres_put(res); + + dlm_put(dlm); + return ret; +} + + + +int dlm_send_proxy_ast_msg(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_lock *lock, int msg_type, + int blocked_type, int flags) +{ + int ret = 0; + struct dlm_proxy_ast past; + struct kvec vec[2]; + size_t veclen = 1; + int status; + + mlog_entry("res %.*s, to=%u, type=%d, blocked_type=%d\n", + res->lockname.len, res->lockname.name, lock->ml.node, + msg_type, blocked_type); + + memset(&past, 0, sizeof(struct dlm_proxy_ast)); + past.node_idx = dlm->node_num; + past.type = msg_type; + past.blocked_type = blocked_type; + past.namelen = res->lockname.len; + memcpy(past.name, res->lockname.name, past.namelen); + past.cookie = lock->ml.cookie; + + vec[0].iov_len = sizeof(struct dlm_proxy_ast); + vec[0].iov_base = &past; + if (flags & DLM_LKSB_GET_LVB) { + mlog(0, "returning requested LVB data\n"); + be32_add_cpu(&past.flags, LKM_GET_LVB); + vec[1].iov_len = DLM_LVB_LEN; + vec[1].iov_base = lock->lksb->lvb; + veclen++; + } + + ret = o2net_send_message_vec(DLM_PROXY_AST_MSG, dlm->key, vec, veclen, + lock->ml.node, &status); + if (ret < 0) + mlog_errno(ret); + else { + if (status == DLM_RECOVERING) { + mlog(ML_ERROR, "sent AST to node %u, it thinks this " + "node is dead!\n", lock->ml.node); + BUG(); + } else if (status == DLM_MIGRATING) { + mlog(ML_ERROR, "sent AST to node %u, it returned " + "DLM_MIGRATING!\n", lock->ml.node); + BUG(); + } else if (status != DLM_NORMAL) { + mlog(ML_ERROR, "AST to node %u returned %d!\n", + lock->ml.node, status); + /* ignore it */ + } + ret = 0; + } + return ret; +} diff --git a/fs/ocfs2/dlm/dlmcommon.h b/fs/ocfs2/dlm/dlmcommon.h new file mode 100644 index 0000000..3fecba0 --- /dev/null +++ b/fs/ocfs2/dlm/dlmcommon.h @@ -0,0 +1,884 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmcommon.h + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + +#ifndef DLMCOMMON_H +#define DLMCOMMON_H + +#include <linux/kref.h> + +#define DLM_HB_NODE_DOWN_PRI (0xf000000) +#define DLM_HB_NODE_UP_PRI (0x8000000) + +#define DLM_LOCKID_NAME_MAX 32 + +#define DLM_DOMAIN_NAME_MAX_LEN 255 +#define DLM_LOCK_RES_OWNER_UNKNOWN O2NM_MAX_NODES +#define DLM_THREAD_SHUFFLE_INTERVAL 5 // flush everything every 5 passes +#define DLM_THREAD_MS 200 // flush at least every 200 ms + +#define DLM_HASH_BITS 7 +#define DLM_HASH_SIZE (1 << DLM_HASH_BITS) +#define DLM_HASH_MASK (DLM_HASH_SIZE - 1) + +enum dlm_ast_type { + DLM_AST = 0, + DLM_BAST, + DLM_ASTUNLOCK +}; + + +#define LKM_VALID_FLAGS (LKM_VALBLK | LKM_CONVERT | LKM_UNLOCK | \ + LKM_CANCEL | LKM_INVVALBLK | LKM_FORCE | \ + LKM_RECOVERY | LKM_LOCAL | LKM_NOQUEUE) + +#define DLM_RECOVERY_LOCK_NAME "$RECOVERY" +#define DLM_RECOVERY_LOCK_NAME_LEN 9 + +static inline int dlm_is_recovery_lock(const char *lock_name, int name_len) +{ + if (name_len == DLM_RECOVERY_LOCK_NAME_LEN && + memcmp(lock_name, DLM_RECOVERY_LOCK_NAME, name_len)==0) + return 1; + return 0; +} + +#define DLM_RECO_STATE_ACTIVE 0x0001 + +struct dlm_recovery_ctxt +{ + struct list_head resources; + struct list_head received; + struct list_head node_data; + u8 new_master; + u8 dead_node; + u16 state; + unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; + wait_queue_head_t event; +}; + +enum dlm_ctxt_state { + DLM_CTXT_NEW = 0, + DLM_CTXT_JOINED, + DLM_CTXT_IN_SHUTDOWN, + DLM_CTXT_LEAVING, +}; + +struct dlm_ctxt +{ + struct list_head list; + struct list_head *resources; + struct list_head dirty_list; + struct list_head purge_list; + struct list_head pending_asts; + struct list_head pending_basts; + unsigned int purge_count; + spinlock_t spinlock; + spinlock_t ast_lock; + char *name; + u8 node_num; + u32 key; + u8 joining_node; + wait_queue_head_t dlm_join_events; + unsigned long live_nodes_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; + unsigned long domain_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; + unsigned long recovery_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; + struct dlm_recovery_ctxt reco; + spinlock_t master_lock; + struct list_head master_list; + struct list_head mle_hb_events; + + /* these give a really vague idea of the system load */ + atomic_t local_resources; + atomic_t remote_resources; + atomic_t unknown_resources; + + /* NOTE: Next three are protected by dlm_domain_lock */ + struct kref dlm_refs; + enum dlm_ctxt_state dlm_state; + unsigned int num_joins; + + struct o2hb_callback_func dlm_hb_up; + struct o2hb_callback_func dlm_hb_down; + struct task_struct *dlm_thread_task; + struct task_struct *dlm_reco_thread_task; + wait_queue_head_t dlm_thread_wq; + wait_queue_head_t dlm_reco_thread_wq; + wait_queue_head_t ast_wq; + wait_queue_head_t migration_wq; + + struct work_struct dispatched_work; + struct list_head work_list; + spinlock_t work_lock; + struct list_head dlm_domain_handlers; + struct list_head dlm_eviction_callbacks; +}; + +/* these keventd work queue items are for less-frequently + * called functions that cannot be directly called from the + * net message handlers for some reason, usually because + * they need to send net messages of their own. */ +void dlm_dispatch_work(void *data); + +struct dlm_lock_resource; +struct dlm_work_item; + +typedef void (dlm_workfunc_t)(struct dlm_work_item *, void *); + +struct dlm_request_all_locks_priv +{ + u8 reco_master; + u8 dead_node; +}; + +struct dlm_mig_lockres_priv +{ + struct dlm_lock_resource *lockres; + u8 real_master; +}; + +struct dlm_assert_master_priv +{ + struct dlm_lock_resource *lockres; + u8 request_from; + u32 flags; + unsigned ignore_higher:1; +}; + + +struct dlm_work_item +{ + struct list_head list; + dlm_workfunc_t *func; + struct dlm_ctxt *dlm; + void *data; + union { + struct dlm_request_all_locks_priv ral; + struct dlm_mig_lockres_priv ml; + struct dlm_assert_master_priv am; + } u; +}; + +static inline void dlm_init_work_item(struct dlm_ctxt *dlm, + struct dlm_work_item *i, + dlm_workfunc_t *f, void *data) +{ + memset(i, 0, sizeof(*i)); + i->func = f; + INIT_LIST_HEAD(&i->list); + i->data = data; + i->dlm = dlm; /* must have already done a dlm_grab on this! */ +} + + + +static inline void __dlm_set_joining_node(struct dlm_ctxt *dlm, + u8 node) +{ + assert_spin_locked(&dlm->spinlock); + + dlm->joining_node = node; + wake_up(&dlm->dlm_join_events); +} + +#define DLM_LOCK_RES_UNINITED 0x00000001 +#define DLM_LOCK_RES_RECOVERING 0x00000002 +#define DLM_LOCK_RES_READY 0x00000004 +#define DLM_LOCK_RES_DIRTY 0x00000008 +#define DLM_LOCK_RES_IN_PROGRESS 0x00000010 +#define DLM_LOCK_RES_MIGRATING 0x00000020 + +#define DLM_PURGE_INTERVAL_MS (8 * 1000) + +struct dlm_lock_resource +{ + /* WARNING: Please see the comment in dlm_init_lockres before + * adding fields here. */ + struct list_head list; + struct kref refs; + + /* please keep these next 3 in this order + * some funcs want to iterate over all lists */ + struct list_head granted; + struct list_head converting; + struct list_head blocked; + + struct list_head dirty; + struct list_head recovering; // dlm_recovery_ctxt.resources list + + /* unused lock resources have their last_used stamped and are + * put on a list for the dlm thread to run. */ + struct list_head purge; + unsigned long last_used; + + unsigned migration_pending:1; + atomic_t asts_reserved; + spinlock_t spinlock; + wait_queue_head_t wq; + u8 owner; //node which owns the lock resource, or unknown + u16 state; + struct qstr lockname; + char lvb[DLM_LVB_LEN]; +}; + +struct dlm_migratable_lock +{ + __be64 cookie; + + /* these 3 are just padding for the in-memory structure, but + * list and flags are actually used when sent over the wire */ + __be16 pad1; + u8 list; // 0=granted, 1=converting, 2=blocked + u8 flags; + + s8 type; + s8 convert_type; + s8 highest_blocked; + u8 node; +}; // 16 bytes + +struct dlm_lock +{ + struct dlm_migratable_lock ml; + + struct list_head list; + struct list_head ast_list; + struct list_head bast_list; + struct dlm_lock_resource *lockres; + spinlock_t spinlock; + struct kref lock_refs; + + // ast and bast must be callable while holding a spinlock! + dlm_astlockfunc_t *ast; + dlm_bastlockfunc_t *bast; + void *astdata; + struct dlm_lockstatus *lksb; + unsigned ast_pending:1, + bast_pending:1, + convert_pending:1, + lock_pending:1, + cancel_pending:1, + unlock_pending:1, + lksb_kernel_allocated:1; +}; + + +#define DLM_LKSB_UNUSED1 0x01 +#define DLM_LKSB_PUT_LVB 0x02 +#define DLM_LKSB_GET_LVB 0x04 +#define DLM_LKSB_UNUSED2 0x08 +#define DLM_LKSB_UNUSED3 0x10 +#define DLM_LKSB_UNUSED4 0x20 +#define DLM_LKSB_UNUSED5 0x40 +#define DLM_LKSB_UNUSED6 0x80 + + +enum dlm_lockres_list { + DLM_GRANTED_LIST = 0, + DLM_CONVERTING_LIST, + DLM_BLOCKED_LIST +}; + +static inline struct list_head * +dlm_list_idx_to_ptr(struct dlm_lock_resource *res, enum dlm_lockres_list idx) +{ + struct list_head *ret = NULL; + if (idx == DLM_GRANTED_LIST) + ret = &res->granted; + else if (idx == DLM_CONVERTING_LIST) + ret = &res->converting; + else if (idx == DLM_BLOCKED_LIST) + ret = &res->blocked; + else + BUG(); + return ret; +} + + + + +struct dlm_node_iter +{ + unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; + int curnode; +}; + + +enum { + DLM_MASTER_REQUEST_MSG = 500, + DLM_UNUSED_MSG1, /* 501 */ + DLM_ASSERT_MASTER_MSG, /* 502 */ + DLM_CREATE_LOCK_MSG, /* 503 */ + DLM_CONVERT_LOCK_MSG, /* 504 */ + DLM_PROXY_AST_MSG, /* 505 */ + DLM_UNLOCK_LOCK_MSG, /* 506 */ + DLM_UNUSED_MSG2, /* 507 */ + DLM_MIGRATE_REQUEST_MSG, /* 508 */ + DLM_MIG_LOCKRES_MSG, /* 509 */ + DLM_QUERY_JOIN_MSG, /* 510 */ + DLM_ASSERT_JOINED_MSG, /* 511 */ + DLM_CANCEL_JOIN_MSG, /* 512 */ + DLM_EXIT_DOMAIN_MSG, /* 513 */ + DLM_MASTER_REQUERY_MSG, /* 514 */ + DLM_LOCK_REQUEST_MSG, /* 515 */ + DLM_RECO_DATA_DONE_MSG, /* 516 */ + DLM_BEGIN_RECO_MSG, /* 517 */ + DLM_FINALIZE_RECO_MSG /* 518 */ +}; + +struct dlm_reco_node_data +{ + int state; + u8 node_num; + struct list_head list; +}; + +enum { + DLM_RECO_NODE_DATA_DEAD = -1, + DLM_RECO_NODE_DATA_INIT = 0, + DLM_RECO_NODE_DATA_REQUESTING, + DLM_RECO_NODE_DATA_REQUESTED, + DLM_RECO_NODE_DATA_RECEIVING, + DLM_RECO_NODE_DATA_DONE, + DLM_RECO_NODE_DATA_FINALIZE_SENT, +}; + + +enum { + DLM_MASTER_RESP_NO = 0, + DLM_MASTER_RESP_YES, + DLM_MASTER_RESP_MAYBE, + DLM_MASTER_RESP_ERROR +}; + + +struct dlm_master_request +{ + u8 node_idx; + u8 namelen; + __be16 pad1; + __be32 flags; + + u8 name[O2NM_MAX_NAME_LEN]; +}; + +#define DLM_ASSERT_MASTER_MLE_CLEANUP 0x00000001 +#define DLM_ASSERT_MASTER_REQUERY 0x00000002 +#define DLM_ASSERT_MASTER_FINISH_MIGRATION 0x00000004 +struct dlm_assert_master +{ + u8 node_idx; + u8 namelen; + __be16 pad1; + __be32 flags; + + u8 name[O2NM_MAX_NAME_LEN]; +}; + +struct dlm_migrate_request +{ + u8 master; + u8 new_master; + u8 namelen; + u8 pad1; + __be32 pad2; + u8 name[O2NM_MAX_NAME_LEN]; +}; + +struct dlm_master_requery +{ + u8 pad1; + u8 pad2; + u8 node_idx; + u8 namelen; + __be32 pad3; + u8 name[O2NM_MAX_NAME_LEN]; +}; + +#define DLM_MRES_RECOVERY 0x01 +#define DLM_MRES_MIGRATION 0x02 +#define DLM_MRES_ALL_DONE 0x04 + +/* + * We would like to get one whole lockres into a single network + * message whenever possible. Generally speaking, there will be + * at most one dlm_lock on a lockres for each node in the cluster, + * plus (infrequently) any additional locks coming in from userdlm. + * + * struct _dlm_lockres_page + * { + * dlm_migratable_lockres mres; + * dlm_migratable_lock ml[DLM_MAX_MIGRATABLE_LOCKS]; + * u8 pad[DLM_MIG_LOCKRES_RESERVED]; + * }; + * + * from ../cluster/tcp.h + * NET_MAX_PAYLOAD_BYTES (4096 - sizeof(net_msg)) + * (roughly 4080 bytes) + * and sizeof(dlm_migratable_lockres) = 112 bytes + * and sizeof(dlm_migratable_lock) = 16 bytes + * + * Choosing DLM_MAX_MIGRATABLE_LOCKS=240 and + * DLM_MIG_LOCKRES_RESERVED=128 means we have this: + * + * (DLM_MAX_MIGRATABLE_LOCKS * sizeof(dlm_migratable_lock)) + + * sizeof(dlm_migratable_lockres) + DLM_MIG_LOCKRES_RESERVED = + * NET_MAX_PAYLOAD_BYTES + * (240 * 16) + 112 + 128 = 4080 + * + * So a lockres would need more than 240 locks before it would + * use more than one network packet to recover. Not too bad. + */ +#define DLM_MAX_MIGRATABLE_LOCKS 240 + +struct dlm_migratable_lockres +{ + u8 master; + u8 lockname_len; + u8 num_locks; // locks sent in this structure + u8 flags; + __be32 total_locks; // locks to be sent for this migration cookie + __be64 mig_cookie; // cookie for this lockres migration + // or zero if not needed + // 16 bytes + u8 lockname[DLM_LOCKID_NAME_MAX]; + // 48 bytes + u8 lvb[DLM_LVB_LEN]; + // 112 bytes + struct dlm_migratable_lock ml[0]; // 16 bytes each, begins at byte 112 +}; +#define DLM_MIG_LOCKRES_MAX_LEN \ + (sizeof(struct dlm_migratable_lockres) + \ + (sizeof(struct dlm_migratable_lock) * \ + DLM_MAX_MIGRATABLE_LOCKS) ) + +/* from above, 128 bytes + * for some undetermined future use */ +#define DLM_MIG_LOCKRES_RESERVED (NET_MAX_PAYLOAD_BYTES - \ + DLM_MIG_LOCKRES_MAX_LEN) + +struct dlm_create_lock +{ + __be64 cookie; + + __be32 flags; + u8 pad1; + u8 node_idx; + s8 requested_type; + u8 namelen; + + u8 name[O2NM_MAX_NAME_LEN]; +}; + +struct dlm_convert_lock +{ + __be64 cookie; + + __be32 flags; + u8 pad1; + u8 node_idx; + s8 requested_type; + u8 namelen; + + u8 name[O2NM_MAX_NAME_LEN]; + + s8 lvb[0]; +}; +#define DLM_CONVERT_LOCK_MAX_LEN (sizeof(struct dlm_convert_lock)+DLM_LVB_LEN) + +struct dlm_unlock_lock +{ + __be64 cookie; + + __be32 flags; + __be16 pad1; + u8 node_idx; + u8 namelen; + + u8 name[O2NM_MAX_NAME_LEN]; + + s8 lvb[0]; +}; +#define DLM_UNLOCK_LOCK_MAX_LEN (sizeof(struct dlm_unlock_lock)+DLM_LVB_LEN) + +struct dlm_proxy_ast +{ + __be64 cookie; + + __be32 flags; + u8 node_idx; + u8 type; + u8 blocked_type; + u8 namelen; + + u8 name[O2NM_MAX_NAME_LEN]; + + s8 lvb[0]; +}; +#define DLM_PROXY_AST_MAX_LEN (sizeof(struct dlm_proxy_ast)+DLM_LVB_LEN) + +#define DLM_MOD_KEY (0x666c6172) +enum dlm_query_join_response { + JOIN_DISALLOW = 0, + JOIN_OK, + JOIN_OK_NO_MAP, +}; + +struct dlm_lock_request +{ + u8 node_idx; + u8 dead_node; + __be16 pad1; + __be32 pad2; +}; + +struct dlm_reco_data_done +{ + u8 node_idx; + u8 dead_node; + __be16 pad1; + __be32 pad2; + + /* unused for now */ + /* eventually we can use this to attempt + * lvb recovery based on each node's info */ + u8 reco_lvb[DLM_LVB_LEN]; +}; + +struct dlm_begin_reco +{ + u8 node_idx; + u8 dead_node; + __be16 pad1; + __be32 pad2; +}; + + +struct dlm_query_join_request +{ + u8 node_idx; + u8 pad1[2]; + u8 name_len; + u8 domain[O2NM_MAX_NAME_LEN]; +}; + +struct dlm_assert_joined +{ + u8 node_idx; + u8 pad1[2]; + u8 name_len; + u8 domain[O2NM_MAX_NAME_LEN]; +}; + +struct dlm_cancel_join +{ + u8 node_idx; + u8 pad1[2]; + u8 name_len; + u8 domain[O2NM_MAX_NAME_LEN]; +}; + +struct dlm_exit_domain +{ + u8 node_idx; + u8 pad1[3]; +}; + +struct dlm_finalize_reco +{ + u8 node_idx; + u8 dead_node; + __be16 pad1; + __be32 pad2; +}; + +static inline enum dlm_status +__dlm_lockres_state_to_status(struct dlm_lock_resource *res) +{ + enum dlm_status status = DLM_NORMAL; + + assert_spin_locked(&res->spinlock); + + if (res->state & DLM_LOCK_RES_RECOVERING) + status = DLM_RECOVERING; + else if (res->state & DLM_LOCK_RES_MIGRATING) + status = DLM_MIGRATING; + else if (res->state & DLM_LOCK_RES_IN_PROGRESS) + status = DLM_FORWARD; + + return status; +} + +struct dlm_lock * dlm_new_lock(int type, u8 node, u64 cookie, + struct dlm_lockstatus *lksb); +void dlm_lock_get(struct dlm_lock *lock); +void dlm_lock_put(struct dlm_lock *lock); + +void dlm_lock_attach_lockres(struct dlm_lock *lock, + struct dlm_lock_resource *res); + +int dlm_create_lock_handler(struct o2net_msg *msg, u32 len, void *data); +int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data); +int dlm_proxy_ast_handler(struct o2net_msg *msg, u32 len, void *data); + +void dlm_revert_pending_convert(struct dlm_lock_resource *res, + struct dlm_lock *lock); +void dlm_revert_pending_lock(struct dlm_lock_resource *res, + struct dlm_lock *lock); + +int dlm_unlock_lock_handler(struct o2net_msg *msg, u32 len, void *data); +void dlm_commit_pending_cancel(struct dlm_lock_resource *res, + struct dlm_lock *lock); +void dlm_commit_pending_unlock(struct dlm_lock_resource *res, + struct dlm_lock *lock); + +int dlm_launch_thread(struct dlm_ctxt *dlm); +void dlm_complete_thread(struct dlm_ctxt *dlm); +int dlm_launch_recovery_thread(struct dlm_ctxt *dlm); +void dlm_complete_recovery_thread(struct dlm_ctxt *dlm); +void dlm_wait_for_recovery(struct dlm_ctxt *dlm); + +void dlm_put(struct dlm_ctxt *dlm); +struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm); +int dlm_domain_fully_joined(struct dlm_ctxt *dlm); + +void __dlm_lockres_calc_usage(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res); +void dlm_lockres_calc_usage(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res); +void dlm_purge_lockres(struct dlm_ctxt *dlm, + struct dlm_lock_resource *lockres); +void dlm_lockres_get(struct dlm_lock_resource *res); +void dlm_lockres_put(struct dlm_lock_resource *res); +void __dlm_unhash_lockres(struct dlm_lock_resource *res); +void __dlm_insert_lockres(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res); +struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm, + const char *name, + unsigned int len); +struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm, + const char *name, + unsigned int len); + +int dlm_is_host_down(int errno); +void dlm_change_lockres_owner(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 owner); +struct dlm_lock_resource * dlm_get_lock_resource(struct dlm_ctxt *dlm, + const char *lockid, + int flags); +struct dlm_lock_resource *dlm_new_lockres(struct dlm_ctxt *dlm, + const char *name, + unsigned int namelen); + +void dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock); +void dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock); +void dlm_do_local_ast(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock); +int dlm_do_remote_ast(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock); +void dlm_do_local_bast(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, + int blocked_type); +int dlm_send_proxy_ast_msg(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, + int msg_type, + int blocked_type, int flags); +static inline int dlm_send_proxy_bast(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, + int blocked_type) +{ + return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_BAST, + blocked_type, 0); +} + +static inline int dlm_send_proxy_ast(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, + int flags) +{ + return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_AST, + 0, flags); +} + +void dlm_print_one_lock_resource(struct dlm_lock_resource *res); +void __dlm_print_one_lock_resource(struct dlm_lock_resource *res); + +u8 dlm_nm_this_node(struct dlm_ctxt *dlm); +void dlm_kick_thread(struct dlm_ctxt *dlm, struct dlm_lock_resource *res); +void __dlm_dirty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res); + + +int dlm_nm_init(struct dlm_ctxt *dlm); +int dlm_heartbeat_init(struct dlm_ctxt *dlm); +void dlm_hb_node_down_cb(struct o2nm_node *node, int idx, void *data); +void dlm_hb_node_up_cb(struct o2nm_node *node, int idx, void *data); + +int dlm_lockres_is_dirty(struct dlm_ctxt *dlm, struct dlm_lock_resource *res); +int dlm_migrate_lockres(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 target); +int dlm_finish_migration(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 old_master); +void dlm_lockres_release_ast(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res); +void __dlm_lockres_reserve_ast(struct dlm_lock_resource *res); + +int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data); +int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data); +int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data); +int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data); +int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data); +int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data); +int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data); +int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data); +int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data); + +int dlm_dispatch_assert_master(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + int ignore_higher, + u8 request_from, + u32 flags); + + +int dlm_send_one_lockres(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_migratable_lockres *mres, + u8 send_to, + u8 flags); +void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res); + +/* will exit holding res->spinlock, but may drop in function */ +void __dlm_wait_on_lockres_flags(struct dlm_lock_resource *res, int flags); +void __dlm_wait_on_lockres_flags_set(struct dlm_lock_resource *res, int flags); + +/* will exit holding res->spinlock, but may drop in function */ +static inline void __dlm_wait_on_lockres(struct dlm_lock_resource *res) +{ + __dlm_wait_on_lockres_flags(res, (DLM_LOCK_RES_IN_PROGRESS| + DLM_LOCK_RES_RECOVERING| + DLM_LOCK_RES_MIGRATING)); +} + + +int dlm_init_mle_cache(void); +void dlm_destroy_mle_cache(void); +void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up); +void dlm_clean_master_list(struct dlm_ctxt *dlm, + u8 dead_node); +int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock); + + +static inline const char * dlm_lock_mode_name(int mode) +{ + switch (mode) { + case LKM_EXMODE: + return "EX"; + case LKM_PRMODE: + return "PR"; + case LKM_NLMODE: + return "NL"; + } + return "UNKNOWN"; +} + + +static inline int dlm_lock_compatible(int existing, int request) +{ + /* NO_LOCK compatible with all */ + if (request == LKM_NLMODE || + existing == LKM_NLMODE) + return 1; + + /* EX incompatible with all non-NO_LOCK */ + if (request == LKM_EXMODE) + return 0; + + /* request must be PR, which is compatible with PR */ + if (existing == LKM_PRMODE) + return 1; + + return 0; +} + +static inline int dlm_lock_on_list(struct list_head *head, + struct dlm_lock *lock) +{ + struct list_head *iter; + struct dlm_lock *tmplock; + + list_for_each(iter, head) { + tmplock = list_entry(iter, struct dlm_lock, list); + if (tmplock == lock) + return 1; + } + return 0; +} + + +static inline enum dlm_status dlm_err_to_dlm_status(int err) +{ + enum dlm_status ret; + if (err == -ENOMEM) + ret = DLM_SYSERR; + else if (err == -ETIMEDOUT || o2net_link_down(err, NULL)) + ret = DLM_NOLOCKMGR; + else if (err == -EINVAL) + ret = DLM_BADPARAM; + else if (err == -ENAMETOOLONG) + ret = DLM_IVBUFLEN; + else + ret = DLM_BADARGS; + return ret; +} + + +static inline void dlm_node_iter_init(unsigned long *map, + struct dlm_node_iter *iter) +{ + memcpy(iter->node_map, map, sizeof(iter->node_map)); + iter->curnode = -1; +} + +static inline int dlm_node_iter_next(struct dlm_node_iter *iter) +{ + int bit; + bit = find_next_bit(iter->node_map, O2NM_MAX_NODES, iter->curnode+1); + if (bit >= O2NM_MAX_NODES) { + iter->curnode = O2NM_MAX_NODES; + return -ENOENT; + } + iter->curnode = bit; + return bit; +} + + + +#endif /* DLMCOMMON_H */ diff --git a/fs/ocfs2/dlm/dlmconvert.c b/fs/ocfs2/dlm/dlmconvert.c new file mode 100644 index 0000000..6001b22 --- /dev/null +++ b/fs/ocfs2/dlm/dlmconvert.c @@ -0,0 +1,530 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmconvert.c + * + * underlying calls for lock conversion + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + + +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/highmem.h> +#include <linux/utsname.h> +#include <linux/init.h> +#include <linux/sysctl.h> +#include <linux/random.h> +#include <linux/blkdev.h> +#include <linux/socket.h> +#include <linux/inet.h> +#include <linux/spinlock.h> + + +#include "cluster/heartbeat.h" +#include "cluster/nodemanager.h" +#include "cluster/tcp.h" + +#include "dlmapi.h" +#include "dlmcommon.h" + +#include "dlmconvert.h" + +#define MLOG_MASK_PREFIX ML_DLM +#include "cluster/masklog.h" + +/* NOTE: __dlmconvert_master is the only function in here that + * needs a spinlock held on entry (res->spinlock) and it is the + * only one that holds a lock on exit (res->spinlock). + * All other functions in here need no locks and drop all of + * the locks that they acquire. */ +static enum dlm_status __dlmconvert_master(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, int flags, + int type, int *call_ast, + int *kick_thread); +static enum dlm_status dlm_send_remote_convert_request(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, int flags, int type); + +/* + * this is only called directly by dlmlock(), and only when the + * local node is the owner of the lockres + * locking: + * caller needs: none + * taken: takes and drops res->spinlock + * held on exit: none + * returns: see __dlmconvert_master + */ +enum dlm_status dlmconvert_master(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, int flags, int type) +{ + int call_ast = 0, kick_thread = 0; + enum dlm_status status; + + spin_lock(&res->spinlock); + /* we are not in a network handler, this is fine */ + __dlm_wait_on_lockres(res); + __dlm_lockres_reserve_ast(res); + res->state |= DLM_LOCK_RES_IN_PROGRESS; + + status = __dlmconvert_master(dlm, res, lock, flags, type, + &call_ast, &kick_thread); + + res->state &= ~DLM_LOCK_RES_IN_PROGRESS; + spin_unlock(&res->spinlock); + wake_up(&res->wq); + if (status != DLM_NORMAL && status != DLM_NOTQUEUED) + dlm_error(status); + + /* either queue the ast or release it */ + if (call_ast) + dlm_queue_ast(dlm, lock); + else + dlm_lockres_release_ast(dlm, res); + + if (kick_thread) + dlm_kick_thread(dlm, res); + + return status; +} + +/* performs lock conversion at the lockres master site + * locking: + * caller needs: res->spinlock + * taken: takes and drops lock->spinlock + * held on exit: res->spinlock + * returns: DLM_NORMAL, DLM_NOTQUEUED, DLM_DENIED + * call_ast: whether ast should be called for this lock + * kick_thread: whether dlm_kick_thread should be called + */ +static enum dlm_status __dlmconvert_master(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, int flags, + int type, int *call_ast, + int *kick_thread) +{ + enum dlm_status status = DLM_NORMAL; + struct list_head *iter; + struct dlm_lock *tmplock=NULL; + + assert_spin_locked(&res->spinlock); + + mlog_entry("type=%d, convert_type=%d, new convert_type=%d\n", + lock->ml.type, lock->ml.convert_type, type); + + spin_lock(&lock->spinlock); + + /* already converting? */ + if (lock->ml.convert_type != LKM_IVMODE) { + mlog(ML_ERROR, "attempted to convert a lock with a lock " + "conversion pending\n"); + status = DLM_DENIED; + goto unlock_exit; + } + + /* must be on grant queue to convert */ + if (!dlm_lock_on_list(&res->granted, lock)) { + mlog(ML_ERROR, "attempted to convert a lock not on grant " + "queue\n"); + status = DLM_DENIED; + goto unlock_exit; + } + + if (flags & LKM_VALBLK) { + switch (lock->ml.type) { + case LKM_EXMODE: + /* EX + LKM_VALBLK + convert == set lvb */ + mlog(0, "will set lvb: converting %s->%s\n", + dlm_lock_mode_name(lock->ml.type), + dlm_lock_mode_name(type)); + lock->lksb->flags |= DLM_LKSB_PUT_LVB; + break; + case LKM_PRMODE: + case LKM_NLMODE: + /* refetch if new level is not NL */ + if (type > LKM_NLMODE) { + mlog(0, "will fetch new value into " + "lvb: converting %s->%s\n", + dlm_lock_mode_name(lock->ml.type), + dlm_lock_mode_name(type)); + lock->lksb->flags |= DLM_LKSB_GET_LVB; + } else { + mlog(0, "will NOT fetch new value " + "into lvb: converting %s->%s\n", + dlm_lock_mode_name(lock->ml.type), + dlm_lock_mode_name(type)); + flags &= ~(LKM_VALBLK); + } + break; + } + } + + + /* in-place downconvert? */ + if (type <= lock->ml.type) + goto grant; + + /* upconvert from here on */ + status = DLM_NORMAL; + list_for_each(iter, &res->granted) { + tmplock = list_entry(iter, struct dlm_lock, list); + if (tmplock == lock) + continue; + if (!dlm_lock_compatible(tmplock->ml.type, type)) + goto switch_queues; + } + + list_for_each(iter, &res->converting) { + tmplock = list_entry(iter, struct dlm_lock, list); + if (!dlm_lock_compatible(tmplock->ml.type, type)) + goto switch_queues; + /* existing conversion requests take precedence */ + if (!dlm_lock_compatible(tmplock->ml.convert_type, type)) + goto switch_queues; + } + + /* fall thru to grant */ + +grant: + mlog(0, "res %.*s, granting %s lock\n", res->lockname.len, + res->lockname.name, dlm_lock_mode_name(type)); + /* immediately grant the new lock type */ + lock->lksb->status = DLM_NORMAL; + if (lock->ml.node == dlm->node_num) + mlog(0, "doing in-place convert for nonlocal lock\n"); + lock->ml.type = type; + status = DLM_NORMAL; + *call_ast = 1; + goto unlock_exit; + +switch_queues: + if (flags & LKM_NOQUEUE) { + mlog(0, "failed to convert NOQUEUE lock %.*s from " + "%d to %d...\n", res->lockname.len, res->lockname.name, + lock->ml.type, type); + status = DLM_NOTQUEUED; + goto unlock_exit; + } + mlog(0, "res %.*s, queueing...\n", res->lockname.len, + res->lockname.name); + + lock->ml.convert_type = type; + /* do not alter lock refcount. switching lists. */ + list_del_init(&lock->list); + list_add_tail(&lock->list, &res->converting); + +unlock_exit: + spin_unlock(&lock->spinlock); + if (status == DLM_DENIED) { + __dlm_print_one_lock_resource(res); + } + if (status == DLM_NORMAL) + *kick_thread = 1; + return status; +} + +void dlm_revert_pending_convert(struct dlm_lock_resource *res, + struct dlm_lock *lock) +{ + /* do not alter lock refcount. switching lists. */ + list_del_init(&lock->list); + list_add_tail(&lock->list, &res->granted); + lock->ml.convert_type = LKM_IVMODE; + lock->lksb->flags &= ~(DLM_LKSB_GET_LVB|DLM_LKSB_PUT_LVB); +} + +/* messages the master site to do lock conversion + * locking: + * caller needs: none + * taken: takes and drops res->spinlock, uses DLM_LOCK_RES_IN_PROGRESS + * held on exit: none + * returns: DLM_NORMAL, DLM_RECOVERING, status from remote node + */ +enum dlm_status dlmconvert_remote(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, int flags, int type) +{ + enum dlm_status status; + + mlog(0, "type=%d, convert_type=%d, busy=%d\n", lock->ml.type, + lock->ml.convert_type, res->state & DLM_LOCK_RES_IN_PROGRESS); + + spin_lock(&res->spinlock); + if (res->state & DLM_LOCK_RES_RECOVERING) { + mlog(0, "bailing out early since res is RECOVERING " + "on secondary queue\n"); + /* __dlm_print_one_lock_resource(res); */ + status = DLM_RECOVERING; + goto bail; + } + /* will exit this call with spinlock held */ + __dlm_wait_on_lockres(res); + + if (lock->ml.convert_type != LKM_IVMODE) { + __dlm_print_one_lock_resource(res); + mlog(ML_ERROR, "converting a remote lock that is already " + "converting! (cookie=%"MLFu64", conv=%d)\n", + lock->ml.cookie, lock->ml.convert_type); + status = DLM_DENIED; + goto bail; + } + res->state |= DLM_LOCK_RES_IN_PROGRESS; + /* move lock to local convert queue */ + /* do not alter lock refcount. switching lists. */ + list_del_init(&lock->list); + list_add_tail(&lock->list, &res->converting); + lock->convert_pending = 1; + lock->ml.convert_type = type; + + if (flags & LKM_VALBLK) { + if (lock->ml.type == LKM_EXMODE) { + flags |= LKM_PUT_LVB; + lock->lksb->flags |= DLM_LKSB_PUT_LVB; + } else { + if (lock->ml.convert_type == LKM_NLMODE) + flags &= ~LKM_VALBLK; + else { + flags |= LKM_GET_LVB; + lock->lksb->flags |= DLM_LKSB_GET_LVB; + } + } + } + spin_unlock(&res->spinlock); + + /* no locks held here. + * need to wait for a reply as to whether it got queued or not. */ + status = dlm_send_remote_convert_request(dlm, res, lock, flags, type); + + spin_lock(&res->spinlock); + res->state &= ~DLM_LOCK_RES_IN_PROGRESS; + lock->convert_pending = 0; + /* if it failed, move it back to granted queue */ + if (status != DLM_NORMAL) { + if (status != DLM_NOTQUEUED) + dlm_error(status); + dlm_revert_pending_convert(res, lock); + } +bail: + spin_unlock(&res->spinlock); + + /* TODO: should this be a wake_one? */ + /* wake up any IN_PROGRESS waiters */ + wake_up(&res->wq); + + return status; +} + +/* sends DLM_CONVERT_LOCK_MSG to master site + * locking: + * caller needs: none + * taken: none + * held on exit: none + * returns: DLM_NOLOCKMGR, status from remote node + */ +static enum dlm_status dlm_send_remote_convert_request(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, int flags, int type) +{ + struct dlm_convert_lock convert; + int tmpret; + enum dlm_status ret; + int status = 0; + struct kvec vec[2]; + size_t veclen = 1; + + mlog_entry("%.*s\n", res->lockname.len, res->lockname.name); + + memset(&convert, 0, sizeof(struct dlm_convert_lock)); + convert.node_idx = dlm->node_num; + convert.requested_type = type; + convert.cookie = lock->ml.cookie; + convert.namelen = res->lockname.len; + convert.flags = cpu_to_be32(flags); + memcpy(convert.name, res->lockname.name, convert.namelen); + + vec[0].iov_len = sizeof(struct dlm_convert_lock); + vec[0].iov_base = &convert; + + if (flags & LKM_PUT_LVB) { + /* extra data to send if we are updating lvb */ + vec[1].iov_len = DLM_LVB_LEN; + vec[1].iov_base = lock->lksb->lvb; + veclen++; + } + + tmpret = o2net_send_message_vec(DLM_CONVERT_LOCK_MSG, dlm->key, + vec, veclen, res->owner, &status); + if (tmpret >= 0) { + // successfully sent and received + ret = status; // this is already a dlm_status + if (ret == DLM_RECOVERING) { + mlog(0, "node %u returned DLM_RECOVERING from convert " + "message!\n", res->owner); + } else if (ret == DLM_MIGRATING) { + mlog(0, "node %u returned DLM_MIGRATING from convert " + "message!\n", res->owner); + } else if (ret == DLM_FORWARD) { + mlog(0, "node %u returned DLM_FORWARD from convert " + "message!\n", res->owner); + } else if (ret != DLM_NORMAL && ret != DLM_NOTQUEUED) + dlm_error(ret); + } else { + mlog_errno(tmpret); + if (dlm_is_host_down(tmpret)) { + ret = DLM_RECOVERING; + mlog(0, "node %u died so returning DLM_RECOVERING " + "from convert message!\n", res->owner); + } else { + ret = dlm_err_to_dlm_status(tmpret); + } + } + + return ret; +} + +/* handler for DLM_CONVERT_LOCK_MSG on master site + * locking: + * caller needs: none + * taken: takes and drop res->spinlock + * held on exit: none + * returns: DLM_NORMAL, DLM_IVLOCKID, DLM_BADARGS, + * status from __dlmconvert_master + */ +int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_convert_lock *cnv = (struct dlm_convert_lock *)msg->buf; + struct dlm_lock_resource *res = NULL; + struct list_head *iter; + struct dlm_lock *lock = NULL; + struct dlm_lockstatus *lksb; + enum dlm_status status = DLM_NORMAL; + u32 flags; + int call_ast = 0, kick_thread = 0; + + if (!dlm_grab(dlm)) { + dlm_error(DLM_REJECTED); + return DLM_REJECTED; + } + + mlog_bug_on_msg(!dlm_domain_fully_joined(dlm), + "Domain %s not fully joined!\n", dlm->name); + + if (cnv->namelen > DLM_LOCKID_NAME_MAX) { + status = DLM_IVBUFLEN; + dlm_error(status); + goto leave; + } + + flags = be32_to_cpu(cnv->flags); + + if ((flags & (LKM_PUT_LVB|LKM_GET_LVB)) == + (LKM_PUT_LVB|LKM_GET_LVB)) { + mlog(ML_ERROR, "both PUT and GET lvb specified\n"); + status = DLM_BADARGS; + goto leave; + } + + mlog(0, "lvb: %s\n", flags & LKM_PUT_LVB ? "put lvb" : + (flags & LKM_GET_LVB ? "get lvb" : "none")); + + status = DLM_IVLOCKID; + res = dlm_lookup_lockres(dlm, cnv->name, cnv->namelen); + if (!res) { + dlm_error(status); + goto leave; + } + + spin_lock(&res->spinlock); + list_for_each(iter, &res->granted) { + lock = list_entry(iter, struct dlm_lock, list); + if (lock->ml.cookie == cnv->cookie && + lock->ml.node == cnv->node_idx) { + dlm_lock_get(lock); + break; + } + lock = NULL; + } + spin_unlock(&res->spinlock); + if (!lock) { + status = DLM_IVLOCKID; + dlm_error(status); + goto leave; + } + + /* found the lock */ + lksb = lock->lksb; + + /* see if caller needed to get/put lvb */ + if (flags & LKM_PUT_LVB) { + BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB)); + lksb->flags |= DLM_LKSB_PUT_LVB; + memcpy(&lksb->lvb[0], &cnv->lvb[0], DLM_LVB_LEN); + } else if (flags & LKM_GET_LVB) { + BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB)); + lksb->flags |= DLM_LKSB_GET_LVB; + } + + spin_lock(&res->spinlock); + status = __dlm_lockres_state_to_status(res); + if (status == DLM_NORMAL) { + __dlm_lockres_reserve_ast(res); + res->state |= DLM_LOCK_RES_IN_PROGRESS; + status = __dlmconvert_master(dlm, res, lock, flags, + cnv->requested_type, + &call_ast, &kick_thread); + res->state &= ~DLM_LOCK_RES_IN_PROGRESS; + } + spin_unlock(&res->spinlock); + + if (status != DLM_NORMAL) { + if (status != DLM_NOTQUEUED) + dlm_error(status); + lksb->flags &= ~(DLM_LKSB_GET_LVB|DLM_LKSB_PUT_LVB); + } + +leave: + if (!lock) + mlog(ML_ERROR, "did not find lock to convert on grant queue! " + "cookie=%"MLFu64"\n", + cnv->cookie); + else + dlm_lock_put(lock); + + /* either queue the ast or release it */ + if (call_ast) + dlm_queue_ast(dlm, lock); + else + dlm_lockres_release_ast(dlm, res); + + if (kick_thread) + dlm_kick_thread(dlm, res); + + if (res) + dlm_lockres_put(res); + + dlm_put(dlm); + + return status; +} diff --git a/fs/ocfs2/dlm/dlmconvert.h b/fs/ocfs2/dlm/dlmconvert.h new file mode 100644 index 0000000..b2e3677 --- /dev/null +++ b/fs/ocfs2/dlm/dlmconvert.h @@ -0,0 +1,35 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmconvert.h + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + +#ifndef DLMCONVERT_H +#define DLMCONVERT_H + +enum dlm_status dlmconvert_master(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, int flags, int type); +enum dlm_status dlmconvert_remote(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, int flags, int type); + +#endif diff --git a/fs/ocfs2/dlm/dlmdebug.c b/fs/ocfs2/dlm/dlmdebug.c new file mode 100644 index 0000000..f339fe27 --- /dev/null +++ b/fs/ocfs2/dlm/dlmdebug.c @@ -0,0 +1,246 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmdebug.c + * + * debug functionality for the dlm + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/highmem.h> +#include <linux/utsname.h> +#include <linux/sysctl.h> +#include <linux/spinlock.h> + +#include "cluster/heartbeat.h" +#include "cluster/nodemanager.h" +#include "cluster/tcp.h" + +#include "dlmapi.h" +#include "dlmcommon.h" +#include "dlmdebug.h" + +#include "dlmdomain.h" +#include "dlmdebug.h" + +#define MLOG_MASK_PREFIX ML_DLM +#include "cluster/masklog.h" + +void dlm_print_one_lock_resource(struct dlm_lock_resource *res) +{ + mlog(ML_NOTICE, "lockres: %.*s, owner=%u, state=%u\n", + res->lockname.len, res->lockname.name, + res->owner, res->state); + spin_lock(&res->spinlock); + __dlm_print_one_lock_resource(res); + spin_unlock(&res->spinlock); +} + +void __dlm_print_one_lock_resource(struct dlm_lock_resource *res) +{ + struct list_head *iter2; + struct dlm_lock *lock; + + assert_spin_locked(&res->spinlock); + + mlog(ML_NOTICE, "lockres: %.*s, owner=%u, state=%u\n", + res->lockname.len, res->lockname.name, + res->owner, res->state); + mlog(ML_NOTICE, " last used: %lu, on purge list: %s\n", + res->last_used, list_empty(&res->purge) ? "no" : "yes"); + mlog(ML_NOTICE, " granted queue: \n"); + list_for_each(iter2, &res->granted) { + lock = list_entry(iter2, struct dlm_lock, list); + spin_lock(&lock->spinlock); + mlog(ML_NOTICE, " type=%d, conv=%d, node=%u, " + "cookie=%"MLFu64", ast=(empty=%c,pend=%c), bast=(empty=%c,pend=%c)\n", + lock->ml.type, lock->ml.convert_type, lock->ml.node, lock->ml.cookie, + list_empty(&lock->ast_list) ? 'y' : 'n', + lock->ast_pending ? 'y' : 'n', + list_empty(&lock->bast_list) ? 'y' : 'n', + lock->bast_pending ? 'y' : 'n'); + spin_unlock(&lock->spinlock); + } + mlog(ML_NOTICE, " converting queue: \n"); + list_for_each(iter2, &res->converting) { + lock = list_entry(iter2, struct dlm_lock, list); + spin_lock(&lock->spinlock); + mlog(ML_NOTICE, " type=%d, conv=%d, node=%u, " + "cookie=%"MLFu64", ast=(empty=%c,pend=%c), bast=(empty=%c,pend=%c)\n", + lock->ml.type, lock->ml.convert_type, lock->ml.node, lock->ml.cookie, + list_empty(&lock->ast_list) ? 'y' : 'n', + lock->ast_pending ? 'y' : 'n', + list_empty(&lock->bast_list) ? 'y' : 'n', + lock->bast_pending ? 'y' : 'n'); + spin_unlock(&lock->spinlock); + } + mlog(ML_NOTICE, " blocked queue: \n"); + list_for_each(iter2, &res->blocked) { + lock = list_entry(iter2, struct dlm_lock, list); + spin_lock(&lock->spinlock); + mlog(ML_NOTICE, " type=%d, conv=%d, node=%u, " + "cookie=%"MLFu64", ast=(empty=%c,pend=%c), bast=(empty=%c,pend=%c)\n", + lock->ml.type, lock->ml.convert_type, lock->ml.node, lock->ml.cookie, + list_empty(&lock->ast_list) ? 'y' : 'n', + lock->ast_pending ? 'y' : 'n', + list_empty(&lock->bast_list) ? 'y' : 'n', + lock->bast_pending ? 'y' : 'n'); + spin_unlock(&lock->spinlock); + } +} + +void dlm_print_one_lock(struct dlm_lock *lockid) +{ + dlm_print_one_lock_resource(lockid->lockres); +} +EXPORT_SYMBOL_GPL(dlm_print_one_lock); + +void dlm_dump_lock_resources(struct dlm_ctxt *dlm) +{ + struct dlm_lock_resource *res; + struct list_head *iter; + struct list_head *bucket; + int i; + + mlog(ML_NOTICE, "struct dlm_ctxt: %s, node=%u, key=%u\n", + dlm->name, dlm->node_num, dlm->key); + if (!dlm || !dlm->name) { + mlog(ML_ERROR, "dlm=%p\n", dlm); + return; + } + + spin_lock(&dlm->spinlock); + for (i=0; i<DLM_HASH_SIZE; i++) { + bucket = &(dlm->resources[i]); + list_for_each(iter, bucket) { + res = list_entry(iter, struct dlm_lock_resource, list); + dlm_print_one_lock_resource(res); + } + } + spin_unlock(&dlm->spinlock); +} + +static const char *dlm_errnames[] = { + [DLM_NORMAL] = "DLM_NORMAL", + [DLM_GRANTED] = "DLM_GRANTED", + [DLM_DENIED] = "DLM_DENIED", + [DLM_DENIED_NOLOCKS] = "DLM_DENIED_NOLOCKS", + [DLM_WORKING] = "DLM_WORKING", + [DLM_BLOCKED] = "DLM_BLOCKED", + [DLM_BLOCKED_ORPHAN] = "DLM_BLOCKED_ORPHAN", + [DLM_DENIED_GRACE_PERIOD] = "DLM_DENIED_GRACE_PERIOD", + [DLM_SYSERR] = "DLM_SYSERR", + [DLM_NOSUPPORT] = "DLM_NOSUPPORT", + [DLM_CANCELGRANT] = "DLM_CANCELGRANT", + [DLM_IVLOCKID] = "DLM_IVLOCKID", + [DLM_SYNC] = "DLM_SYNC", + [DLM_BADTYPE] = "DLM_BADTYPE", + [DLM_BADRESOURCE] = "DLM_BADRESOURCE", + [DLM_MAXHANDLES] = "DLM_MAXHANDLES", + [DLM_NOCLINFO] = "DLM_NOCLINFO", + [DLM_NOLOCKMGR] = "DLM_NOLOCKMGR", + [DLM_NOPURGED] = "DLM_NOPURGED", + [DLM_BADARGS] = "DLM_BADARGS", + [DLM_VOID] = "DLM_VOID", + [DLM_NOTQUEUED] = "DLM_NOTQUEUED", + [DLM_IVBUFLEN] = "DLM_IVBUFLEN", + [DLM_CVTUNGRANT] = "DLM_CVTUNGRANT", + [DLM_BADPARAM] = "DLM_BADPARAM", + [DLM_VALNOTVALID] = "DLM_VALNOTVALID", + [DLM_REJECTED] = "DLM_REJECTED", + [DLM_ABORT] = "DLM_ABORT", + [DLM_CANCEL] = "DLM_CANCEL", + [DLM_IVRESHANDLE] = "DLM_IVRESHANDLE", + [DLM_DEADLOCK] = "DLM_DEADLOCK", + [DLM_DENIED_NOASTS] = "DLM_DENIED_NOASTS", + [DLM_FORWARD] = "DLM_FORWARD", + [DLM_TIMEOUT] = "DLM_TIMEOUT", + [DLM_IVGROUPID] = "DLM_IVGROUPID", + [DLM_VERS_CONFLICT] = "DLM_VERS_CONFLICT", + [DLM_BAD_DEVICE_PATH] = "DLM_BAD_DEVICE_PATH", + [DLM_NO_DEVICE_PERMISSION] = "DLM_NO_DEVICE_PERMISSION", + [DLM_NO_CONTROL_DEVICE ] = "DLM_NO_CONTROL_DEVICE ", + [DLM_RECOVERING] = "DLM_RECOVERING", + [DLM_MIGRATING] = "DLM_MIGRATING", + [DLM_MAXSTATS] = "DLM_MAXSTATS", +}; + +static const char *dlm_errmsgs[] = { + [DLM_NORMAL] = "request in progress", + [DLM_GRANTED] = "request granted", + [DLM_DENIED] = "request denied", + [DLM_DENIED_NOLOCKS] = "request denied, out of system resources", + [DLM_WORKING] = "async request in progress", + [DLM_BLOCKED] = "lock request blocked", + [DLM_BLOCKED_ORPHAN] = "lock request blocked by a orphan lock", + [DLM_DENIED_GRACE_PERIOD] = "topological change in progress", + [DLM_SYSERR] = "system error", + [DLM_NOSUPPORT] = "unsupported", + [DLM_CANCELGRANT] = "can't cancel convert: already granted", + [DLM_IVLOCKID] = "bad lockid", + [DLM_SYNC] = "synchronous request granted", + [DLM_BADTYPE] = "bad resource type", + [DLM_BADRESOURCE] = "bad resource handle", + [DLM_MAXHANDLES] = "no more resource handles", + [DLM_NOCLINFO] = "can't contact cluster manager", + [DLM_NOLOCKMGR] = "can't contact lock manager", + [DLM_NOPURGED] = "can't contact purge daemon", + [DLM_BADARGS] = "bad api args", + [DLM_VOID] = "no status", + [DLM_NOTQUEUED] = "NOQUEUE was specified and request failed", + [DLM_IVBUFLEN] = "invalid resource name length", + [DLM_CVTUNGRANT] = "attempted to convert ungranted lock", + [DLM_BADPARAM] = "invalid lock mode specified", + [DLM_VALNOTVALID] = "value block has been invalidated", + [DLM_REJECTED] = "request rejected, unrecognized client", + [DLM_ABORT] = "blocked lock request cancelled", + [DLM_CANCEL] = "conversion request cancelled", + [DLM_IVRESHANDLE] = "invalid resource handle", + [DLM_DEADLOCK] = "deadlock recovery refused this request", + [DLM_DENIED_NOASTS] = "failed to allocate AST", + [DLM_FORWARD] = "request must wait for primary's response", + [DLM_TIMEOUT] = "timeout value for lock has expired", + [DLM_IVGROUPID] = "invalid group specification", + [DLM_VERS_CONFLICT] = "version conflicts prevent request handling", + [DLM_BAD_DEVICE_PATH] = "Locks device does not exist or path wrong", + [DLM_NO_DEVICE_PERMISSION] = "Client has insufficient perms for device", + [DLM_NO_CONTROL_DEVICE] = "Cannot set options on opened device ", + [DLM_RECOVERING] = "lock resource being recovered", + [DLM_MIGRATING] = "lock resource being migrated", + [DLM_MAXSTATS] = "invalid error number", +}; + +const char *dlm_errmsg(enum dlm_status err) +{ + if (err >= DLM_MAXSTATS || err < 0) + return dlm_errmsgs[DLM_MAXSTATS]; + return dlm_errmsgs[err]; +} +EXPORT_SYMBOL_GPL(dlm_errmsg); + +const char *dlm_errname(enum dlm_status err) +{ + if (err >= DLM_MAXSTATS || err < 0) + return dlm_errnames[DLM_MAXSTATS]; + return dlm_errnames[err]; +} +EXPORT_SYMBOL_GPL(dlm_errname); diff --git a/fs/ocfs2/dlm/dlmdebug.h b/fs/ocfs2/dlm/dlmdebug.h new file mode 100644 index 0000000..6858510 --- /dev/null +++ b/fs/ocfs2/dlm/dlmdebug.h @@ -0,0 +1,30 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmdebug.h + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + +#ifndef DLMDEBUG_H +#define DLMDEBUG_H + +void dlm_dump_lock_resources(struct dlm_ctxt *dlm); + +#endif diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c new file mode 100644 index 0000000..da3c220 --- /dev/null +++ b/fs/ocfs2/dlm/dlmdomain.c @@ -0,0 +1,1469 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmdomain.c + * + * defines domain join / leave apis + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/highmem.h> +#include <linux/utsname.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/delay.h> +#include <linux/err.h> + +#include "cluster/heartbeat.h" +#include "cluster/nodemanager.h" +#include "cluster/tcp.h" + +#include "dlmapi.h" +#include "dlmcommon.h" + +#include "dlmdebug.h" +#include "dlmdomain.h" + +#include "dlmver.h" + +#define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_DOMAIN) +#include "cluster/masklog.h" + +/* + * + * spinlock lock ordering: if multiple locks are needed, obey this ordering: + * dlm_domain_lock + * struct dlm_ctxt->spinlock + * struct dlm_lock_resource->spinlock + * struct dlm_ctxt->master_lock + * struct dlm_ctxt->ast_lock + * dlm_master_list_entry->spinlock + * dlm_lock->spinlock + * + */ + +spinlock_t dlm_domain_lock = SPIN_LOCK_UNLOCKED; +LIST_HEAD(dlm_domains); +static DECLARE_WAIT_QUEUE_HEAD(dlm_domain_events); + +#define DLM_DOMAIN_BACKOFF_MS 200 + +static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data); +static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data); +static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data); +static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data); + +static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm); + +void __dlm_unhash_lockres(struct dlm_lock_resource *lockres) +{ + list_del_init(&lockres->list); + dlm_lockres_put(lockres); +} + +void __dlm_insert_lockres(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res) +{ + struct list_head *bucket; + struct qstr *q; + + assert_spin_locked(&dlm->spinlock); + + q = &res->lockname; + q->hash = full_name_hash(q->name, q->len); + bucket = &(dlm->resources[q->hash & DLM_HASH_MASK]); + + /* get a reference for our hashtable */ + dlm_lockres_get(res); + + list_add_tail(&res->list, bucket); +} + +struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm, + const char *name, + unsigned int len) +{ + unsigned int hash; + struct list_head *iter; + struct dlm_lock_resource *tmpres=NULL; + struct list_head *bucket; + + mlog_entry("%.*s\n", len, name); + + assert_spin_locked(&dlm->spinlock); + + hash = full_name_hash(name, len); + + bucket = &(dlm->resources[hash & DLM_HASH_MASK]); + + /* check for pre-existing lock */ + list_for_each(iter, bucket) { + tmpres = list_entry(iter, struct dlm_lock_resource, list); + if (tmpres->lockname.len == len && + memcmp(tmpres->lockname.name, name, len) == 0) { + dlm_lockres_get(tmpres); + break; + } + + tmpres = NULL; + } + return tmpres; +} + +struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm, + const char *name, + unsigned int len) +{ + struct dlm_lock_resource *res; + + spin_lock(&dlm->spinlock); + res = __dlm_lookup_lockres(dlm, name, len); + spin_unlock(&dlm->spinlock); + return res; +} + +static struct dlm_ctxt * __dlm_lookup_domain_full(const char *domain, int len) +{ + struct dlm_ctxt *tmp = NULL; + struct list_head *iter; + + assert_spin_locked(&dlm_domain_lock); + + /* tmp->name here is always NULL terminated, + * but domain may not be! */ + list_for_each(iter, &dlm_domains) { + tmp = list_entry (iter, struct dlm_ctxt, list); + if (strlen(tmp->name) == len && + memcmp(tmp->name, domain, len)==0) + break; + tmp = NULL; + } + + return tmp; +} + +/* For null terminated domain strings ONLY */ +static struct dlm_ctxt * __dlm_lookup_domain(const char *domain) +{ + assert_spin_locked(&dlm_domain_lock); + + return __dlm_lookup_domain_full(domain, strlen(domain)); +} + + +/* returns true on one of two conditions: + * 1) the domain does not exist + * 2) the domain exists and it's state is "joined" */ +static int dlm_wait_on_domain_helper(const char *domain) +{ + int ret = 0; + struct dlm_ctxt *tmp = NULL; + + spin_lock(&dlm_domain_lock); + + tmp = __dlm_lookup_domain(domain); + if (!tmp) + ret = 1; + else if (tmp->dlm_state == DLM_CTXT_JOINED) + ret = 1; + + spin_unlock(&dlm_domain_lock); + return ret; +} + +static void dlm_free_ctxt_mem(struct dlm_ctxt *dlm) +{ + if (dlm->resources) + free_page((unsigned long) dlm->resources); + + if (dlm->name) + kfree(dlm->name); + + kfree(dlm); +} + +/* A little strange - this function will be called while holding + * dlm_domain_lock and is expected to be holding it on the way out. We + * will however drop and reacquire it multiple times */ +static void dlm_ctxt_release(struct kref *kref) +{ + struct dlm_ctxt *dlm; + + dlm = container_of(kref, struct dlm_ctxt, dlm_refs); + + BUG_ON(dlm->num_joins); + BUG_ON(dlm->dlm_state == DLM_CTXT_JOINED); + + /* we may still be in the list if we hit an error during join. */ + list_del_init(&dlm->list); + + spin_unlock(&dlm_domain_lock); + + mlog(0, "freeing memory from domain %s\n", dlm->name); + + wake_up(&dlm_domain_events); + + dlm_free_ctxt_mem(dlm); + + spin_lock(&dlm_domain_lock); +} + +void dlm_put(struct dlm_ctxt *dlm) +{ + spin_lock(&dlm_domain_lock); + kref_put(&dlm->dlm_refs, dlm_ctxt_release); + spin_unlock(&dlm_domain_lock); +} + +static void __dlm_get(struct dlm_ctxt *dlm) +{ + kref_get(&dlm->dlm_refs); +} + +/* given a questionable reference to a dlm object, gets a reference if + * it can find it in the list, otherwise returns NULL in which case + * you shouldn't trust your pointer. */ +struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm) +{ + struct list_head *iter; + struct dlm_ctxt *target = NULL; + + spin_lock(&dlm_domain_lock); + + list_for_each(iter, &dlm_domains) { + target = list_entry (iter, struct dlm_ctxt, list); + + if (target == dlm) { + __dlm_get(target); + break; + } + + target = NULL; + } + + spin_unlock(&dlm_domain_lock); + + return target; +} + +int dlm_domain_fully_joined(struct dlm_ctxt *dlm) +{ + int ret; + + spin_lock(&dlm_domain_lock); + ret = (dlm->dlm_state == DLM_CTXT_JOINED) || + (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN); + spin_unlock(&dlm_domain_lock); + + return ret; +} + +static void dlm_complete_dlm_shutdown(struct dlm_ctxt *dlm) +{ + dlm_unregister_domain_handlers(dlm); + dlm_complete_thread(dlm); + dlm_complete_recovery_thread(dlm); + + /* We've left the domain. Now we can take ourselves out of the + * list and allow the kref stuff to help us free the + * memory. */ + spin_lock(&dlm_domain_lock); + list_del_init(&dlm->list); + spin_unlock(&dlm_domain_lock); + + /* Wake up anyone waiting for us to remove this domain */ + wake_up(&dlm_domain_events); +} + +static void dlm_migrate_all_locks(struct dlm_ctxt *dlm) +{ + int i; + struct dlm_lock_resource *res; + + mlog(0, "Migrating locks from domain %s\n", dlm->name); +restart: + spin_lock(&dlm->spinlock); + for (i=0; i<DLM_HASH_SIZE; i++) { + while (!list_empty(&dlm->resources[i])) { + res = list_entry(dlm->resources[i].next, + struct dlm_lock_resource, list); + /* need reference when manually grabbing lockres */ + dlm_lockres_get(res); + /* this should unhash the lockres + * and exit with dlm->spinlock */ + mlog(0, "purging res=%p\n", res); + if (dlm_lockres_is_dirty(dlm, res)) { + /* HACK! this should absolutely go. + * need to figure out why some empty + * lockreses are still marked dirty */ + mlog(ML_ERROR, "lockres %.*s dirty!\n", + res->lockname.len, res->lockname.name); + + spin_unlock(&dlm->spinlock); + dlm_kick_thread(dlm, res); + wait_event(dlm->ast_wq, !dlm_lockres_is_dirty(dlm, res)); + dlm_lockres_put(res); + goto restart; + } + dlm_purge_lockres(dlm, res); + dlm_lockres_put(res); + } + } + spin_unlock(&dlm->spinlock); + + mlog(0, "DONE Migrating locks from domain %s\n", dlm->name); +} + +static int dlm_no_joining_node(struct dlm_ctxt *dlm) +{ + int ret; + + spin_lock(&dlm->spinlock); + ret = dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN; + spin_unlock(&dlm->spinlock); + + return ret; +} + +static void dlm_mark_domain_leaving(struct dlm_ctxt *dlm) +{ + /* Yikes, a double spinlock! I need domain_lock for the dlm + * state and the dlm spinlock for join state... Sorry! */ +again: + spin_lock(&dlm_domain_lock); + spin_lock(&dlm->spinlock); + + if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) { + mlog(0, "Node %d is joining, we wait on it.\n", + dlm->joining_node); + spin_unlock(&dlm->spinlock); + spin_unlock(&dlm_domain_lock); + + wait_event(dlm->dlm_join_events, dlm_no_joining_node(dlm)); + goto again; + } + + dlm->dlm_state = DLM_CTXT_LEAVING; + spin_unlock(&dlm->spinlock); + spin_unlock(&dlm_domain_lock); +} + +static void __dlm_print_nodes(struct dlm_ctxt *dlm) +{ + int node = -1; + + assert_spin_locked(&dlm->spinlock); + + mlog(ML_NOTICE, "Nodes in my domain (\"%s\"):\n", dlm->name); + + while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES, + node + 1)) < O2NM_MAX_NODES) { + mlog(ML_NOTICE, " node %d\n", node); + } +} + +static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + unsigned int node; + struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf; + + mlog_entry("%p %u %p", msg, len, data); + + if (!dlm_grab(dlm)) + return 0; + + node = exit_msg->node_idx; + + mlog(0, "Node %u leaves domain %s\n", node, dlm->name); + + spin_lock(&dlm->spinlock); + clear_bit(node, dlm->domain_map); + __dlm_print_nodes(dlm); + + /* notify anything attached to the heartbeat events */ + dlm_hb_event_notify_attached(dlm, node, 0); + + spin_unlock(&dlm->spinlock); + + dlm_put(dlm); + + return 0; +} + +static int dlm_send_one_domain_exit(struct dlm_ctxt *dlm, + unsigned int node) +{ + int status; + struct dlm_exit_domain leave_msg; + + mlog(0, "Asking node %u if we can leave the domain %s me = %u\n", + node, dlm->name, dlm->node_num); + + memset(&leave_msg, 0, sizeof(leave_msg)); + leave_msg.node_idx = dlm->node_num; + + status = o2net_send_message(DLM_EXIT_DOMAIN_MSG, dlm->key, + &leave_msg, sizeof(leave_msg), node, + NULL); + + mlog(0, "status return %d from o2net_send_message\n", status); + + return status; +} + + +static void dlm_leave_domain(struct dlm_ctxt *dlm) +{ + int node, clear_node, status; + + /* At this point we've migrated away all our locks and won't + * accept mastership of new ones. The dlm is responsible for + * almost nothing now. We make sure not to confuse any joining + * nodes and then commence shutdown procedure. */ + + spin_lock(&dlm->spinlock); + /* Clear ourselves from the domain map */ + clear_bit(dlm->node_num, dlm->domain_map); + while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES, + 0)) < O2NM_MAX_NODES) { + /* Drop the dlm spinlock. This is safe wrt the domain_map. + * -nodes cannot be added now as the + * query_join_handlers knows to respond with OK_NO_MAP + * -we catch the right network errors if a node is + * removed from the map while we're sending him the + * exit message. */ + spin_unlock(&dlm->spinlock); + + clear_node = 1; + + status = dlm_send_one_domain_exit(dlm, node); + if (status < 0 && + status != -ENOPROTOOPT && + status != -ENOTCONN) { + mlog(ML_NOTICE, "Error %d sending domain exit message " + "to node %d\n", status, node); + + /* Not sure what to do here but lets sleep for + * a bit in case this was a transient + * error... */ + msleep(DLM_DOMAIN_BACKOFF_MS); + clear_node = 0; + } + + spin_lock(&dlm->spinlock); + /* If we're not clearing the node bit then we intend + * to loop back around to try again. */ + if (clear_node) + clear_bit(node, dlm->domain_map); + } + spin_unlock(&dlm->spinlock); +} + +int dlm_joined(struct dlm_ctxt *dlm) +{ + int ret = 0; + + spin_lock(&dlm_domain_lock); + + if (dlm->dlm_state == DLM_CTXT_JOINED) + ret = 1; + + spin_unlock(&dlm_domain_lock); + + return ret; +} + +int dlm_shutting_down(struct dlm_ctxt *dlm) +{ + int ret = 0; + + spin_lock(&dlm_domain_lock); + + if (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN) + ret = 1; + + spin_unlock(&dlm_domain_lock); + + return ret; +} + +void dlm_unregister_domain(struct dlm_ctxt *dlm) +{ + int leave = 0; + + spin_lock(&dlm_domain_lock); + BUG_ON(dlm->dlm_state != DLM_CTXT_JOINED); + BUG_ON(!dlm->num_joins); + + dlm->num_joins--; + if (!dlm->num_joins) { + /* We mark it "in shutdown" now so new register + * requests wait until we've completely left the + * domain. Don't use DLM_CTXT_LEAVING yet as we still + * want new domain joins to communicate with us at + * least until we've completed migration of our + * resources. */ + dlm->dlm_state = DLM_CTXT_IN_SHUTDOWN; + leave = 1; + } + spin_unlock(&dlm_domain_lock); + + if (leave) { + mlog(0, "shutting down domain %s\n", dlm->name); + + /* We changed dlm state, notify the thread */ + dlm_kick_thread(dlm, NULL); + + dlm_migrate_all_locks(dlm); + dlm_mark_domain_leaving(dlm); + dlm_leave_domain(dlm); + dlm_complete_dlm_shutdown(dlm); + } + dlm_put(dlm); +} +EXPORT_SYMBOL_GPL(dlm_unregister_domain); + +static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_query_join_request *query; + enum dlm_query_join_response response; + struct dlm_ctxt *dlm = NULL; + + query = (struct dlm_query_join_request *) msg->buf; + + mlog(0, "node %u wants to join domain %s\n", query->node_idx, + query->domain); + + /* + * If heartbeat doesn't consider the node live, tell it + * to back off and try again. This gives heartbeat a chance + * to catch up. + */ + if (!o2hb_check_node_heartbeating(query->node_idx)) { + mlog(0, "node %u is not in our live map yet\n", + query->node_idx); + + response = JOIN_DISALLOW; + goto respond; + } + + response = JOIN_OK_NO_MAP; + + spin_lock(&dlm_domain_lock); + dlm = __dlm_lookup_domain_full(query->domain, query->name_len); + /* Once the dlm ctxt is marked as leaving then we don't want + * to be put in someone's domain map. */ + if (dlm && dlm->dlm_state != DLM_CTXT_LEAVING) { + spin_lock(&dlm->spinlock); + + if (dlm->dlm_state == DLM_CTXT_NEW && + dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN) { + /*If this is a brand new context and we + * haven't started our join process yet, then + * the other node won the race. */ + response = JOIN_OK_NO_MAP; + } else if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) { + /* Disallow parallel joins. */ + response = JOIN_DISALLOW; + } else { + /* Alright we're fully a part of this domain + * so we keep some state as to who's joining + * and indicate to him that needs to be fixed + * up. */ + response = JOIN_OK; + __dlm_set_joining_node(dlm, query->node_idx); + } + + spin_unlock(&dlm->spinlock); + } + spin_unlock(&dlm_domain_lock); + +respond: + mlog(0, "We respond with %u\n", response); + + return response; +} + +static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_assert_joined *assert; + struct dlm_ctxt *dlm = NULL; + + assert = (struct dlm_assert_joined *) msg->buf; + + mlog(0, "node %u asserts join on domain %s\n", assert->node_idx, + assert->domain); + + spin_lock(&dlm_domain_lock); + dlm = __dlm_lookup_domain_full(assert->domain, assert->name_len); + /* XXX should we consider no dlm ctxt an error? */ + if (dlm) { + spin_lock(&dlm->spinlock); + + /* Alright, this node has officially joined our + * domain. Set him in the map and clean up our + * leftover join state. */ + BUG_ON(dlm->joining_node != assert->node_idx); + set_bit(assert->node_idx, dlm->domain_map); + __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN); + + __dlm_print_nodes(dlm); + + /* notify anything attached to the heartbeat events */ + dlm_hb_event_notify_attached(dlm, assert->node_idx, 1); + + spin_unlock(&dlm->spinlock); + } + spin_unlock(&dlm_domain_lock); + + return 0; +} + +static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_cancel_join *cancel; + struct dlm_ctxt *dlm = NULL; + + cancel = (struct dlm_cancel_join *) msg->buf; + + mlog(0, "node %u cancels join on domain %s\n", cancel->node_idx, + cancel->domain); + + spin_lock(&dlm_domain_lock); + dlm = __dlm_lookup_domain_full(cancel->domain, cancel->name_len); + + if (dlm) { + spin_lock(&dlm->spinlock); + + /* Yikes, this guy wants to cancel his join. No + * problem, we simply cleanup our join state. */ + BUG_ON(dlm->joining_node != cancel->node_idx); + __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN); + + spin_unlock(&dlm->spinlock); + } + spin_unlock(&dlm_domain_lock); + + return 0; +} + +static int dlm_send_one_join_cancel(struct dlm_ctxt *dlm, + unsigned int node) +{ + int status; + struct dlm_cancel_join cancel_msg; + + memset(&cancel_msg, 0, sizeof(cancel_msg)); + cancel_msg.node_idx = dlm->node_num; + cancel_msg.name_len = strlen(dlm->name); + memcpy(cancel_msg.domain, dlm->name, cancel_msg.name_len); + + status = o2net_send_message(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY, + &cancel_msg, sizeof(cancel_msg), node, + NULL); + if (status < 0) { + mlog_errno(status); + goto bail; + } + +bail: + return status; +} + +/* map_size should be in bytes. */ +static int dlm_send_join_cancels(struct dlm_ctxt *dlm, + unsigned long *node_map, + unsigned int map_size) +{ + int status, tmpstat; + unsigned int node; + + if (map_size != (BITS_TO_LONGS(O2NM_MAX_NODES) * + sizeof(unsigned long))) { + mlog(ML_ERROR, + "map_size %u != BITS_TO_LONGS(O2NM_MAX_NODES) %u\n", + map_size, BITS_TO_LONGS(O2NM_MAX_NODES)); + return -EINVAL; + } + + status = 0; + node = -1; + while ((node = find_next_bit(node_map, O2NM_MAX_NODES, + node + 1)) < O2NM_MAX_NODES) { + if (node == dlm->node_num) + continue; + + tmpstat = dlm_send_one_join_cancel(dlm, node); + if (tmpstat) { + mlog(ML_ERROR, "Error return %d cancelling join on " + "node %d\n", tmpstat, node); + if (!status) + status = tmpstat; + } + } + + if (status) + mlog_errno(status); + return status; +} + +static int dlm_request_join(struct dlm_ctxt *dlm, + int node, + enum dlm_query_join_response *response) +{ + int status, retval; + struct dlm_query_join_request join_msg; + + mlog(0, "querying node %d\n", node); + + memset(&join_msg, 0, sizeof(join_msg)); + join_msg.node_idx = dlm->node_num; + join_msg.name_len = strlen(dlm->name); + memcpy(join_msg.domain, dlm->name, join_msg.name_len); + + status = o2net_send_message(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, &join_msg, + sizeof(join_msg), node, &retval); + if (status < 0 && status != -ENOPROTOOPT) { + mlog_errno(status); + goto bail; + } + + /* -ENOPROTOOPT from the net code means the other side isn't + listening for our message type -- that's fine, it means + his dlm isn't up, so we can consider him a 'yes' but not + joined into the domain. */ + if (status == -ENOPROTOOPT) { + status = 0; + *response = JOIN_OK_NO_MAP; + } else if (retval == JOIN_DISALLOW || + retval == JOIN_OK || + retval == JOIN_OK_NO_MAP) { + *response = retval; + } else { + status = -EINVAL; + mlog(ML_ERROR, "invalid response %d from node %u\n", retval, + node); + } + + mlog(0, "status %d, node %d response is %d\n", status, node, + *response); + +bail: + return status; +} + +static int dlm_send_one_join_assert(struct dlm_ctxt *dlm, + unsigned int node) +{ + int status; + struct dlm_assert_joined assert_msg; + + mlog(0, "Sending join assert to node %u\n", node); + + memset(&assert_msg, 0, sizeof(assert_msg)); + assert_msg.node_idx = dlm->node_num; + assert_msg.name_len = strlen(dlm->name); + memcpy(assert_msg.domain, dlm->name, assert_msg.name_len); + + status = o2net_send_message(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY, + &assert_msg, sizeof(assert_msg), node, + NULL); + if (status < 0) + mlog_errno(status); + + return status; +} + +static void dlm_send_join_asserts(struct dlm_ctxt *dlm, + unsigned long *node_map) +{ + int status, node, live; + + status = 0; + node = -1; + while ((node = find_next_bit(node_map, O2NM_MAX_NODES, + node + 1)) < O2NM_MAX_NODES) { + if (node == dlm->node_num) + continue; + + do { + /* It is very important that this message be + * received so we spin until either the node + * has died or it gets the message. */ + status = dlm_send_one_join_assert(dlm, node); + + spin_lock(&dlm->spinlock); + live = test_bit(node, dlm->live_nodes_map); + spin_unlock(&dlm->spinlock); + + if (status) { + mlog(ML_ERROR, "Error return %d asserting " + "join on node %d\n", status, node); + + /* give us some time between errors... */ + if (live) + msleep(DLM_DOMAIN_BACKOFF_MS); + } + } while (status && live); + } +} + +struct domain_join_ctxt { + unsigned long live_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; + unsigned long yes_resp_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; +}; + +static int dlm_should_restart_join(struct dlm_ctxt *dlm, + struct domain_join_ctxt *ctxt, + enum dlm_query_join_response response) +{ + int ret; + + if (response == JOIN_DISALLOW) { + mlog(0, "Latest response of disallow -- should restart\n"); + return 1; + } + + spin_lock(&dlm->spinlock); + /* For now, we restart the process if the node maps have + * changed at all */ + ret = memcmp(ctxt->live_map, dlm->live_nodes_map, + sizeof(dlm->live_nodes_map)); + spin_unlock(&dlm->spinlock); + + if (ret) + mlog(0, "Node maps changed -- should restart\n"); + + return ret; +} + +static int dlm_try_to_join_domain(struct dlm_ctxt *dlm) +{ + int status = 0, tmpstat, node; + struct domain_join_ctxt *ctxt; + enum dlm_query_join_response response; + + mlog_entry("%p", dlm); + + ctxt = kcalloc(1, sizeof(*ctxt), GFP_KERNEL); + if (!ctxt) { + status = -ENOMEM; + mlog_errno(status); + goto bail; + } + + /* group sem locking should work for us here -- we're already + * registered for heartbeat events so filling this should be + * atomic wrt getting those handlers called. */ + o2hb_fill_node_map(dlm->live_nodes_map, sizeof(dlm->live_nodes_map)); + + spin_lock(&dlm->spinlock); + memcpy(ctxt->live_map, dlm->live_nodes_map, sizeof(ctxt->live_map)); + + __dlm_set_joining_node(dlm, dlm->node_num); + + spin_unlock(&dlm->spinlock); + + node = -1; + while ((node = find_next_bit(ctxt->live_map, O2NM_MAX_NODES, + node + 1)) < O2NM_MAX_NODES) { + if (node == dlm->node_num) + continue; + + status = dlm_request_join(dlm, node, &response); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + /* Ok, either we got a response or the node doesn't have a + * dlm up. */ + if (response == JOIN_OK) + set_bit(node, ctxt->yes_resp_map); + + if (dlm_should_restart_join(dlm, ctxt, response)) { + status = -EAGAIN; + goto bail; + } + } + + mlog(0, "Yay, done querying nodes!\n"); + + /* Yay, everyone agree's we can join the domain. My domain is + * comprised of all nodes who were put in the + * yes_resp_map. Copy that into our domain map and send a join + * assert message to clean up everyone elses state. */ + spin_lock(&dlm->spinlock); + memcpy(dlm->domain_map, ctxt->yes_resp_map, + sizeof(ctxt->yes_resp_map)); + set_bit(dlm->node_num, dlm->domain_map); + spin_unlock(&dlm->spinlock); + + dlm_send_join_asserts(dlm, ctxt->yes_resp_map); + + /* Joined state *must* be set before the joining node + * information, otherwise the query_join handler may read no + * current joiner but a state of NEW and tell joining nodes + * we're not in the domain. */ + spin_lock(&dlm_domain_lock); + dlm->dlm_state = DLM_CTXT_JOINED; + dlm->num_joins++; + spin_unlock(&dlm_domain_lock); + +bail: + spin_lock(&dlm->spinlock); + __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN); + if (!status) + __dlm_print_nodes(dlm); + spin_unlock(&dlm->spinlock); + + if (ctxt) { + /* Do we need to send a cancel message to any nodes? */ + if (status < 0) { + tmpstat = dlm_send_join_cancels(dlm, + ctxt->yes_resp_map, + sizeof(ctxt->yes_resp_map)); + if (tmpstat < 0) + mlog_errno(tmpstat); + } + kfree(ctxt); + } + + mlog(0, "returning %d\n", status); + return status; +} + +static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm) +{ + o2hb_unregister_callback(&dlm->dlm_hb_up); + o2hb_unregister_callback(&dlm->dlm_hb_down); + o2net_unregister_handler_list(&dlm->dlm_domain_handlers); +} + +static int dlm_register_domain_handlers(struct dlm_ctxt *dlm) +{ + int status; + + mlog(0, "registering handlers.\n"); + + o2hb_setup_callback(&dlm->dlm_hb_down, O2HB_NODE_DOWN_CB, + dlm_hb_node_down_cb, dlm, DLM_HB_NODE_DOWN_PRI); + status = o2hb_register_callback(&dlm->dlm_hb_down); + if (status) + goto bail; + + o2hb_setup_callback(&dlm->dlm_hb_up, O2HB_NODE_UP_CB, + dlm_hb_node_up_cb, dlm, DLM_HB_NODE_UP_PRI); + status = o2hb_register_callback(&dlm->dlm_hb_up); + if (status) + goto bail; + + status = o2net_register_handler(DLM_MASTER_REQUEST_MSG, dlm->key, + sizeof(struct dlm_master_request), + dlm_master_request_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_ASSERT_MASTER_MSG, dlm->key, + sizeof(struct dlm_assert_master), + dlm_assert_master_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_CREATE_LOCK_MSG, dlm->key, + sizeof(struct dlm_create_lock), + dlm_create_lock_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_CONVERT_LOCK_MSG, dlm->key, + DLM_CONVERT_LOCK_MAX_LEN, + dlm_convert_lock_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_UNLOCK_LOCK_MSG, dlm->key, + DLM_UNLOCK_LOCK_MAX_LEN, + dlm_unlock_lock_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_PROXY_AST_MSG, dlm->key, + DLM_PROXY_AST_MAX_LEN, + dlm_proxy_ast_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_EXIT_DOMAIN_MSG, dlm->key, + sizeof(struct dlm_exit_domain), + dlm_exit_domain_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_MIGRATE_REQUEST_MSG, dlm->key, + sizeof(struct dlm_migrate_request), + dlm_migrate_request_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_MIG_LOCKRES_MSG, dlm->key, + DLM_MIG_LOCKRES_MAX_LEN, + dlm_mig_lockres_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_MASTER_REQUERY_MSG, dlm->key, + sizeof(struct dlm_master_requery), + dlm_master_requery_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_LOCK_REQUEST_MSG, dlm->key, + sizeof(struct dlm_lock_request), + dlm_request_all_locks_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_RECO_DATA_DONE_MSG, dlm->key, + sizeof(struct dlm_reco_data_done), + dlm_reco_data_done_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_BEGIN_RECO_MSG, dlm->key, + sizeof(struct dlm_begin_reco), + dlm_begin_reco_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_FINALIZE_RECO_MSG, dlm->key, + sizeof(struct dlm_finalize_reco), + dlm_finalize_reco_handler, + dlm, &dlm->dlm_domain_handlers); + if (status) + goto bail; + +bail: + if (status) + dlm_unregister_domain_handlers(dlm); + + return status; +} + +static int dlm_join_domain(struct dlm_ctxt *dlm) +{ + int status; + + BUG_ON(!dlm); + + mlog(0, "Join domain %s\n", dlm->name); + + status = dlm_register_domain_handlers(dlm); + if (status) { + mlog_errno(status); + goto bail; + } + + status = dlm_launch_thread(dlm); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + status = dlm_launch_recovery_thread(dlm); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + do { + unsigned int backoff; + status = dlm_try_to_join_domain(dlm); + + /* If we're racing another node to the join, then we + * need to back off temporarily and let them + * complete. */ + if (status == -EAGAIN) { + if (signal_pending(current)) { + status = -ERESTARTSYS; + goto bail; + } + + /* + * <chip> After you! + * <dale> No, after you! + * <chip> I insist! + * <dale> But you first! + * ... + */ + backoff = (unsigned int)(jiffies & 0x3); + backoff *= DLM_DOMAIN_BACKOFF_MS; + mlog(0, "backoff %d\n", backoff); + msleep(backoff); + } + } while (status == -EAGAIN); + + if (status < 0) { + mlog_errno(status); + goto bail; + } + + status = 0; +bail: + wake_up(&dlm_domain_events); + + if (status) { + dlm_unregister_domain_handlers(dlm); + dlm_complete_thread(dlm); + dlm_complete_recovery_thread(dlm); + } + + return status; +} + +static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain, + u32 key) +{ + int i; + struct dlm_ctxt *dlm = NULL; + + dlm = kcalloc(1, sizeof(*dlm), GFP_KERNEL); + if (!dlm) { + mlog_errno(-ENOMEM); + goto leave; + } + + dlm->name = kmalloc(strlen(domain) + 1, GFP_KERNEL); + if (dlm->name == NULL) { + mlog_errno(-ENOMEM); + kfree(dlm); + dlm = NULL; + goto leave; + } + + dlm->resources = (struct list_head *) __get_free_page(GFP_KERNEL); + if (!dlm->resources) { + mlog_errno(-ENOMEM); + kfree(dlm->name); + kfree(dlm); + dlm = NULL; + goto leave; + } + memset(dlm->resources, 0, PAGE_SIZE); + + for (i=0; i<DLM_HASH_SIZE; i++) + INIT_LIST_HEAD(&dlm->resources[i]); + + strcpy(dlm->name, domain); + dlm->key = key; + dlm->node_num = o2nm_this_node(); + + spin_lock_init(&dlm->spinlock); + spin_lock_init(&dlm->master_lock); + spin_lock_init(&dlm->ast_lock); + INIT_LIST_HEAD(&dlm->list); + INIT_LIST_HEAD(&dlm->dirty_list); + INIT_LIST_HEAD(&dlm->reco.resources); + INIT_LIST_HEAD(&dlm->reco.received); + INIT_LIST_HEAD(&dlm->reco.node_data); + INIT_LIST_HEAD(&dlm->purge_list); + INIT_LIST_HEAD(&dlm->dlm_domain_handlers); + dlm->reco.state = 0; + + INIT_LIST_HEAD(&dlm->pending_asts); + INIT_LIST_HEAD(&dlm->pending_basts); + + mlog(0, "dlm->recovery_map=%p, &(dlm->recovery_map[0])=%p\n", + dlm->recovery_map, &(dlm->recovery_map[0])); + + memset(dlm->recovery_map, 0, sizeof(dlm->recovery_map)); + memset(dlm->live_nodes_map, 0, sizeof(dlm->live_nodes_map)); + memset(dlm->domain_map, 0, sizeof(dlm->domain_map)); + + dlm->dlm_thread_task = NULL; + dlm->dlm_reco_thread_task = NULL; + init_waitqueue_head(&dlm->dlm_thread_wq); + init_waitqueue_head(&dlm->dlm_reco_thread_wq); + init_waitqueue_head(&dlm->reco.event); + init_waitqueue_head(&dlm->ast_wq); + init_waitqueue_head(&dlm->migration_wq); + INIT_LIST_HEAD(&dlm->master_list); + INIT_LIST_HEAD(&dlm->mle_hb_events); + + dlm->joining_node = DLM_LOCK_RES_OWNER_UNKNOWN; + init_waitqueue_head(&dlm->dlm_join_events); + + dlm->reco.new_master = O2NM_INVALID_NODE_NUM; + dlm->reco.dead_node = O2NM_INVALID_NODE_NUM; + atomic_set(&dlm->local_resources, 0); + atomic_set(&dlm->remote_resources, 0); + atomic_set(&dlm->unknown_resources, 0); + + spin_lock_init(&dlm->work_lock); + INIT_LIST_HEAD(&dlm->work_list); + INIT_WORK(&dlm->dispatched_work, dlm_dispatch_work, dlm); + + kref_init(&dlm->dlm_refs); + dlm->dlm_state = DLM_CTXT_NEW; + + INIT_LIST_HEAD(&dlm->dlm_eviction_callbacks); + + mlog(0, "context init: refcount %u\n", + atomic_read(&dlm->dlm_refs.refcount)); + +leave: + return dlm; +} + +/* + * dlm_register_domain: one-time setup per "domain" + */ +struct dlm_ctxt * dlm_register_domain(const char *domain, + u32 key) +{ + int ret; + struct dlm_ctxt *dlm = NULL; + struct dlm_ctxt *new_ctxt = NULL; + + if (strlen(domain) > O2NM_MAX_NAME_LEN) { + ret = -ENAMETOOLONG; + mlog(ML_ERROR, "domain name length too long\n"); + goto leave; + } + + if (!o2hb_check_local_node_heartbeating()) { + mlog(ML_ERROR, "the local node has not been configured, or is " + "not heartbeating\n"); + ret = -EPROTO; + goto leave; + } + + mlog(0, "register called for domain \"%s\"\n", domain); + +retry: + dlm = NULL; + if (signal_pending(current)) { + ret = -ERESTARTSYS; + mlog_errno(ret); + goto leave; + } + + spin_lock(&dlm_domain_lock); + + dlm = __dlm_lookup_domain(domain); + if (dlm) { + if (dlm->dlm_state != DLM_CTXT_JOINED) { + spin_unlock(&dlm_domain_lock); + + mlog(0, "This ctxt is not joined yet!\n"); + wait_event_interruptible(dlm_domain_events, + dlm_wait_on_domain_helper( + domain)); + goto retry; + } + + __dlm_get(dlm); + dlm->num_joins++; + + spin_unlock(&dlm_domain_lock); + + ret = 0; + goto leave; + } + + /* doesn't exist */ + if (!new_ctxt) { + spin_unlock(&dlm_domain_lock); + + new_ctxt = dlm_alloc_ctxt(domain, key); + if (new_ctxt) + goto retry; + + ret = -ENOMEM; + mlog_errno(ret); + goto leave; + } + + /* a little variable switch-a-roo here... */ + dlm = new_ctxt; + new_ctxt = NULL; + + /* add the new domain */ + list_add_tail(&dlm->list, &dlm_domains); + spin_unlock(&dlm_domain_lock); + + ret = dlm_join_domain(dlm); + if (ret) { + mlog_errno(ret); + dlm_put(dlm); + goto leave; + } + + ret = 0; +leave: + if (new_ctxt) + dlm_free_ctxt_mem(new_ctxt); + + if (ret < 0) + dlm = ERR_PTR(ret); + + return dlm; +} +EXPORT_SYMBOL_GPL(dlm_register_domain); + +static LIST_HEAD(dlm_join_handlers); + +static void dlm_unregister_net_handlers(void) +{ + o2net_unregister_handler_list(&dlm_join_handlers); +} + +static int dlm_register_net_handlers(void) +{ + int status = 0; + + status = o2net_register_handler(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, + sizeof(struct dlm_query_join_request), + dlm_query_join_handler, + NULL, &dlm_join_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY, + sizeof(struct dlm_assert_joined), + dlm_assert_joined_handler, + NULL, &dlm_join_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY, + sizeof(struct dlm_cancel_join), + dlm_cancel_join_handler, + NULL, &dlm_join_handlers); + +bail: + if (status < 0) + dlm_unregister_net_handlers(); + + return status; +} + +/* Domain eviction callback handling. + * + * The file system requires notification of node death *before* the + * dlm completes it's recovery work, otherwise it may be able to + * acquire locks on resources requiring recovery. Since the dlm can + * evict a node from it's domain *before* heartbeat fires, a similar + * mechanism is required. */ + +/* Eviction is not expected to happen often, so a per-domain lock is + * not necessary. Eviction callbacks are allowed to sleep for short + * periods of time. */ +static DECLARE_RWSEM(dlm_callback_sem); + +void dlm_fire_domain_eviction_callbacks(struct dlm_ctxt *dlm, + int node_num) +{ + struct list_head *iter; + struct dlm_eviction_cb *cb; + + down_read(&dlm_callback_sem); + list_for_each(iter, &dlm->dlm_eviction_callbacks) { + cb = list_entry(iter, struct dlm_eviction_cb, ec_item); + + cb->ec_func(node_num, cb->ec_data); + } + up_read(&dlm_callback_sem); +} + +void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb, + dlm_eviction_func *f, + void *data) +{ + INIT_LIST_HEAD(&cb->ec_item); + cb->ec_func = f; + cb->ec_data = data; +} +EXPORT_SYMBOL_GPL(dlm_setup_eviction_cb); + +void dlm_register_eviction_cb(struct dlm_ctxt *dlm, + struct dlm_eviction_cb *cb) +{ + down_write(&dlm_callback_sem); + list_add_tail(&cb->ec_item, &dlm->dlm_eviction_callbacks); + up_write(&dlm_callback_sem); +} +EXPORT_SYMBOL_GPL(dlm_register_eviction_cb); + +void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb) +{ + down_write(&dlm_callback_sem); + list_del_init(&cb->ec_item); + up_write(&dlm_callback_sem); +} +EXPORT_SYMBOL_GPL(dlm_unregister_eviction_cb); + +static int __init dlm_init(void) +{ + int status; + + dlm_print_version(); + + status = dlm_init_mle_cache(); + if (status) + return -1; + + status = dlm_register_net_handlers(); + if (status) { + dlm_destroy_mle_cache(); + return -1; + } + + return 0; +} + +static void __exit dlm_exit (void) +{ + dlm_unregister_net_handlers(); + dlm_destroy_mle_cache(); +} + +MODULE_AUTHOR("Oracle"); +MODULE_LICENSE("GPL"); + +module_init(dlm_init); +module_exit(dlm_exit); diff --git a/fs/ocfs2/dlm/dlmdomain.h b/fs/ocfs2/dlm/dlmdomain.h new file mode 100644 index 0000000..2f7f60b --- /dev/null +++ b/fs/ocfs2/dlm/dlmdomain.h @@ -0,0 +1,36 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmdomain.h + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + +#ifndef DLMDOMAIN_H +#define DLMDOMAIN_H + +extern spinlock_t dlm_domain_lock; +extern struct list_head dlm_domains; + +int dlm_joined(struct dlm_ctxt *dlm); +int dlm_shutting_down(struct dlm_ctxt *dlm); +void dlm_fire_domain_eviction_callbacks(struct dlm_ctxt *dlm, + int node_num); + +#endif diff --git a/fs/ocfs2/dlm/dlmlock.c b/fs/ocfs2/dlm/dlmlock.c new file mode 100644 index 0000000..d1a0038 --- /dev/null +++ b/fs/ocfs2/dlm/dlmlock.c @@ -0,0 +1,676 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmlock.c + * + * underlying calls for lock creation + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + + +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/highmem.h> +#include <linux/utsname.h> +#include <linux/init.h> +#include <linux/sysctl.h> +#include <linux/random.h> +#include <linux/blkdev.h> +#include <linux/socket.h> +#include <linux/inet.h> +#include <linux/spinlock.h> +#include <linux/delay.h> + + +#include "cluster/heartbeat.h" +#include "cluster/nodemanager.h" +#include "cluster/tcp.h" + +#include "dlmapi.h" +#include "dlmcommon.h" + +#include "dlmconvert.h" + +#define MLOG_MASK_PREFIX ML_DLM +#include "cluster/masklog.h" + +static spinlock_t dlm_cookie_lock = SPIN_LOCK_UNLOCKED; +static u64 dlm_next_cookie = 1; + +static enum dlm_status dlm_send_remote_lock_request(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, int flags); +static void dlm_init_lock(struct dlm_lock *newlock, int type, + u8 node, u64 cookie); +static void dlm_lock_release(struct kref *kref); +static void dlm_lock_detach_lockres(struct dlm_lock *lock); + +/* Tell us whether we can grant a new lock request. + * locking: + * caller needs: res->spinlock + * taken: none + * held on exit: none + * returns: 1 if the lock can be granted, 0 otherwise. + */ +static int dlm_can_grant_new_lock(struct dlm_lock_resource *res, + struct dlm_lock *lock) +{ + struct list_head *iter; + struct dlm_lock *tmplock; + + list_for_each(iter, &res->granted) { + tmplock = list_entry(iter, struct dlm_lock, list); + + if (!dlm_lock_compatible(tmplock->ml.type, lock->ml.type)) + return 0; + } + + list_for_each(iter, &res->converting) { + tmplock = list_entry(iter, struct dlm_lock, list); + + if (!dlm_lock_compatible(tmplock->ml.type, lock->ml.type)) + return 0; + } + + return 1; +} + +/* performs lock creation at the lockres master site + * locking: + * caller needs: none + * taken: takes and drops res->spinlock + * held on exit: none + * returns: DLM_NORMAL, DLM_NOTQUEUED + */ +static enum dlm_status dlmlock_master(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, int flags) +{ + int call_ast = 0, kick_thread = 0; + enum dlm_status status = DLM_NORMAL; + + mlog_entry("type=%d\n", lock->ml.type); + + spin_lock(&res->spinlock); + /* if called from dlm_create_lock_handler, need to + * ensure it will not sleep in dlm_wait_on_lockres */ + status = __dlm_lockres_state_to_status(res); + if (status != DLM_NORMAL && + lock->ml.node != dlm->node_num) { + /* erf. state changed after lock was dropped. */ + spin_unlock(&res->spinlock); + dlm_error(status); + return status; + } + __dlm_wait_on_lockres(res); + __dlm_lockres_reserve_ast(res); + + if (dlm_can_grant_new_lock(res, lock)) { + mlog(0, "I can grant this lock right away\n"); + /* got it right away */ + lock->lksb->status = DLM_NORMAL; + status = DLM_NORMAL; + dlm_lock_get(lock); + list_add_tail(&lock->list, &res->granted); + + /* for the recovery lock, we can't allow the ast + * to be queued since the dlmthread is already + * frozen. but the recovery lock is always locked + * with LKM_NOQUEUE so we do not need the ast in + * this special case */ + if (!dlm_is_recovery_lock(res->lockname.name, + res->lockname.len)) { + kick_thread = 1; + call_ast = 1; + } + } else { + /* for NOQUEUE request, unless we get the + * lock right away, return DLM_NOTQUEUED */ + if (flags & LKM_NOQUEUE) + status = DLM_NOTQUEUED; + else { + dlm_lock_get(lock); + list_add_tail(&lock->list, &res->blocked); + kick_thread = 1; + } + } + + spin_unlock(&res->spinlock); + wake_up(&res->wq); + + /* either queue the ast or release it */ + if (call_ast) + dlm_queue_ast(dlm, lock); + else + dlm_lockres_release_ast(dlm, res); + + dlm_lockres_calc_usage(dlm, res); + if (kick_thread) + dlm_kick_thread(dlm, res); + + return status; +} + +void dlm_revert_pending_lock(struct dlm_lock_resource *res, + struct dlm_lock *lock) +{ + /* remove from local queue if it failed */ + list_del_init(&lock->list); + lock->lksb->flags &= ~DLM_LKSB_GET_LVB; +} + + +/* + * locking: + * caller needs: none + * taken: takes and drops res->spinlock + * held on exit: none + * returns: DLM_DENIED, DLM_RECOVERING, or net status + */ +static enum dlm_status dlmlock_remote(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, int flags) +{ + enum dlm_status status = DLM_DENIED; + + mlog_entry("type=%d\n", lock->ml.type); + mlog(0, "lockres %.*s, flags = 0x%x\n", res->lockname.len, + res->lockname.name, flags); + + spin_lock(&res->spinlock); + + /* will exit this call with spinlock held */ + __dlm_wait_on_lockres(res); + res->state |= DLM_LOCK_RES_IN_PROGRESS; + + /* add lock to local (secondary) queue */ + dlm_lock_get(lock); + list_add_tail(&lock->list, &res->blocked); + lock->lock_pending = 1; + spin_unlock(&res->spinlock); + + /* spec seems to say that you will get DLM_NORMAL when the lock + * has been queued, meaning we need to wait for a reply here. */ + status = dlm_send_remote_lock_request(dlm, res, lock, flags); + + spin_lock(&res->spinlock); + res->state &= ~DLM_LOCK_RES_IN_PROGRESS; + lock->lock_pending = 0; + if (status != DLM_NORMAL) { + if (status != DLM_NOTQUEUED) + dlm_error(status); + dlm_revert_pending_lock(res, lock); + dlm_lock_put(lock); + } + spin_unlock(&res->spinlock); + + dlm_lockres_calc_usage(dlm, res); + + wake_up(&res->wq); + return status; +} + + +/* for remote lock creation. + * locking: + * caller needs: none, but need res->state & DLM_LOCK_RES_IN_PROGRESS + * taken: none + * held on exit: none + * returns: DLM_NOLOCKMGR, or net status + */ +static enum dlm_status dlm_send_remote_lock_request(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, int flags) +{ + struct dlm_create_lock create; + int tmpret, status = 0; + enum dlm_status ret; + + mlog_entry_void(); + + memset(&create, 0, sizeof(create)); + create.node_idx = dlm->node_num; + create.requested_type = lock->ml.type; + create.cookie = lock->ml.cookie; + create.namelen = res->lockname.len; + create.flags = cpu_to_be32(flags); + memcpy(create.name, res->lockname.name, create.namelen); + + tmpret = o2net_send_message(DLM_CREATE_LOCK_MSG, dlm->key, &create, + sizeof(create), res->owner, &status); + if (tmpret >= 0) { + // successfully sent and received + ret = status; // this is already a dlm_status + } else { + mlog_errno(tmpret); + if (dlm_is_host_down(tmpret)) { + ret = DLM_RECOVERING; + mlog(0, "node %u died so returning DLM_RECOVERING " + "from lock message!\n", res->owner); + } else { + ret = dlm_err_to_dlm_status(tmpret); + } + } + + return ret; +} + +void dlm_lock_get(struct dlm_lock *lock) +{ + kref_get(&lock->lock_refs); +} + +void dlm_lock_put(struct dlm_lock *lock) +{ + kref_put(&lock->lock_refs, dlm_lock_release); +} + +static void dlm_lock_release(struct kref *kref) +{ + struct dlm_lock *lock; + + lock = container_of(kref, struct dlm_lock, lock_refs); + + BUG_ON(!list_empty(&lock->list)); + BUG_ON(!list_empty(&lock->ast_list)); + BUG_ON(!list_empty(&lock->bast_list)); + BUG_ON(lock->ast_pending); + BUG_ON(lock->bast_pending); + + dlm_lock_detach_lockres(lock); + + if (lock->lksb_kernel_allocated) { + mlog(0, "freeing kernel-allocated lksb\n"); + kfree(lock->lksb); + } + kfree(lock); +} + +/* associate a lock with it's lockres, getting a ref on the lockres */ +void dlm_lock_attach_lockres(struct dlm_lock *lock, + struct dlm_lock_resource *res) +{ + dlm_lockres_get(res); + lock->lockres = res; +} + +/* drop ref on lockres, if there is still one associated with lock */ +static void dlm_lock_detach_lockres(struct dlm_lock *lock) +{ + struct dlm_lock_resource *res; + + res = lock->lockres; + if (res) { + lock->lockres = NULL; + mlog(0, "removing lock's lockres reference\n"); + dlm_lockres_put(res); + } +} + +static void dlm_init_lock(struct dlm_lock *newlock, int type, + u8 node, u64 cookie) +{ + INIT_LIST_HEAD(&newlock->list); + INIT_LIST_HEAD(&newlock->ast_list); + INIT_LIST_HEAD(&newlock->bast_list); + spin_lock_init(&newlock->spinlock); + newlock->ml.type = type; + newlock->ml.convert_type = LKM_IVMODE; + newlock->ml.highest_blocked = LKM_IVMODE; + newlock->ml.node = node; + newlock->ml.pad1 = 0; + newlock->ml.list = 0; + newlock->ml.flags = 0; + newlock->ast = NULL; + newlock->bast = NULL; + newlock->astdata = NULL; + newlock->ml.cookie = cpu_to_be64(cookie); + newlock->ast_pending = 0; + newlock->bast_pending = 0; + newlock->convert_pending = 0; + newlock->lock_pending = 0; + newlock->unlock_pending = 0; + newlock->cancel_pending = 0; + newlock->lksb_kernel_allocated = 0; + + kref_init(&newlock->lock_refs); +} + +struct dlm_lock * dlm_new_lock(int type, u8 node, u64 cookie, + struct dlm_lockstatus *lksb) +{ + struct dlm_lock *lock; + int kernel_allocated = 0; + + lock = kcalloc(1, sizeof(*lock), GFP_KERNEL); + if (!lock) + return NULL; + + if (!lksb) { + /* zero memory only if kernel-allocated */ + lksb = kcalloc(1, sizeof(*lksb), GFP_KERNEL); + if (!lksb) { + kfree(lock); + return NULL; + } + kernel_allocated = 1; + } + + dlm_init_lock(lock, type, node, cookie); + if (kernel_allocated) + lock->lksb_kernel_allocated = 1; + lock->lksb = lksb; + lksb->lockid = lock; + return lock; +} + +/* handler for lock creation net message + * locking: + * caller needs: none + * taken: takes and drops res->spinlock + * held on exit: none + * returns: DLM_NORMAL, DLM_SYSERR, DLM_IVLOCKID, DLM_NOTQUEUED + */ +int dlm_create_lock_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_create_lock *create = (struct dlm_create_lock *)msg->buf; + struct dlm_lock_resource *res = NULL; + struct dlm_lock *newlock = NULL; + struct dlm_lockstatus *lksb = NULL; + enum dlm_status status = DLM_NORMAL; + char *name; + unsigned int namelen; + + BUG_ON(!dlm); + + mlog_entry_void(); + + if (!dlm_grab(dlm)) + return DLM_REJECTED; + + mlog_bug_on_msg(!dlm_domain_fully_joined(dlm), + "Domain %s not fully joined!\n", dlm->name); + + name = create->name; + namelen = create->namelen; + + status = DLM_IVBUFLEN; + if (namelen > DLM_LOCKID_NAME_MAX) { + dlm_error(status); + goto leave; + } + + status = DLM_SYSERR; + newlock = dlm_new_lock(create->requested_type, + create->node_idx, + be64_to_cpu(create->cookie), NULL); + if (!newlock) { + dlm_error(status); + goto leave; + } + + lksb = newlock->lksb; + + if (be32_to_cpu(create->flags) & LKM_GET_LVB) { + lksb->flags |= DLM_LKSB_GET_LVB; + mlog(0, "set DLM_LKSB_GET_LVB flag\n"); + } + + status = DLM_IVLOCKID; + res = dlm_lookup_lockres(dlm, name, namelen); + if (!res) { + dlm_error(status); + goto leave; + } + + spin_lock(&res->spinlock); + status = __dlm_lockres_state_to_status(res); + spin_unlock(&res->spinlock); + + if (status != DLM_NORMAL) { + mlog(0, "lockres recovering/migrating/in-progress\n"); + goto leave; + } + + dlm_lock_attach_lockres(newlock, res); + + status = dlmlock_master(dlm, res, newlock, be32_to_cpu(create->flags)); +leave: + if (status != DLM_NORMAL) + if (newlock) + dlm_lock_put(newlock); + + if (res) + dlm_lockres_put(res); + + dlm_put(dlm); + + return status; +} + + +/* fetch next node-local (u8 nodenum + u56 cookie) into u64 */ +static inline void dlm_get_next_cookie(u8 node_num, u64 *cookie) +{ + u64 tmpnode = node_num; + + /* shift single byte of node num into top 8 bits */ + tmpnode <<= 56; + + spin_lock(&dlm_cookie_lock); + *cookie = (dlm_next_cookie | tmpnode); + if (++dlm_next_cookie & 0xff00000000000000ull) { + mlog(0, "This node's cookie will now wrap!\n"); + dlm_next_cookie = 1; + } + spin_unlock(&dlm_cookie_lock); +} + +enum dlm_status dlmlock(struct dlm_ctxt *dlm, int mode, + struct dlm_lockstatus *lksb, int flags, + const char *name, dlm_astlockfunc_t *ast, void *data, + dlm_bastlockfunc_t *bast) +{ + enum dlm_status status; + struct dlm_lock_resource *res = NULL; + struct dlm_lock *lock = NULL; + int convert = 0, recovery = 0; + + /* yes this function is a mess. + * TODO: clean this up. lots of common code in the + * lock and convert paths, especially in the retry blocks */ + if (!lksb) { + dlm_error(DLM_BADARGS); + return DLM_BADARGS; + } + + status = DLM_BADPARAM; + if (mode != LKM_EXMODE && mode != LKM_PRMODE && mode != LKM_NLMODE) { + dlm_error(status); + goto error; + } + + if (flags & ~LKM_VALID_FLAGS) { + dlm_error(status); + goto error; + } + + convert = (flags & LKM_CONVERT); + recovery = (flags & LKM_RECOVERY); + + if (recovery && + (!dlm_is_recovery_lock(name, strlen(name)) || convert) ) { + dlm_error(status); + goto error; + } + if (convert && (flags & LKM_LOCAL)) { + mlog(ML_ERROR, "strange LOCAL convert request!\n"); + goto error; + } + + if (convert) { + /* CONVERT request */ + + /* if converting, must pass in a valid dlm_lock */ + lock = lksb->lockid; + if (!lock) { + mlog(ML_ERROR, "NULL lock pointer in convert " + "request\n"); + goto error; + } + + res = lock->lockres; + if (!res) { + mlog(ML_ERROR, "NULL lockres pointer in convert " + "request\n"); + goto error; + } + dlm_lockres_get(res); + + /* XXX: for ocfs2 purposes, the ast/bast/astdata/lksb are + * static after the original lock call. convert requests will + * ensure that everything is the same, or return DLM_BADARGS. + * this means that DLM_DENIED_NOASTS will never be returned. + */ + if (lock->lksb != lksb || lock->ast != ast || + lock->bast != bast || lock->astdata != data) { + status = DLM_BADARGS; + mlog(ML_ERROR, "new args: lksb=%p, ast=%p, bast=%p, " + "astdata=%p\n", lksb, ast, bast, data); + mlog(ML_ERROR, "orig args: lksb=%p, ast=%p, bast=%p, " + "astdata=%p\n", lock->lksb, lock->ast, + lock->bast, lock->astdata); + goto error; + } +retry_convert: + dlm_wait_for_recovery(dlm); + + if (res->owner == dlm->node_num) + status = dlmconvert_master(dlm, res, lock, flags, mode); + else + status = dlmconvert_remote(dlm, res, lock, flags, mode); + if (status == DLM_RECOVERING || status == DLM_MIGRATING || + status == DLM_FORWARD) { + /* for now, see how this works without sleeping + * and just retry right away. I suspect the reco + * or migration will complete fast enough that + * no waiting will be necessary */ + mlog(0, "retrying convert with migration/recovery/" + "in-progress\n"); + msleep(100); + goto retry_convert; + } + } else { + u64 tmpcookie; + + /* LOCK request */ + status = DLM_BADARGS; + if (!name) { + dlm_error(status); + goto error; + } + + status = DLM_IVBUFLEN; + if (strlen(name) > DLM_LOCKID_NAME_MAX || strlen(name) < 1) { + dlm_error(status); + goto error; + } + + dlm_get_next_cookie(dlm->node_num, &tmpcookie); + lock = dlm_new_lock(mode, dlm->node_num, tmpcookie, lksb); + if (!lock) { + dlm_error(status); + goto error; + } + + if (!recovery) + dlm_wait_for_recovery(dlm); + + /* find or create the lock resource */ + res = dlm_get_lock_resource(dlm, name, flags); + if (!res) { + status = DLM_IVLOCKID; + dlm_error(status); + goto error; + } + + mlog(0, "type=%d, flags = 0x%x\n", mode, flags); + mlog(0, "creating lock: lock=%p res=%p\n", lock, res); + + dlm_lock_attach_lockres(lock, res); + lock->ast = ast; + lock->bast = bast; + lock->astdata = data; + +retry_lock: + if (flags & LKM_VALBLK) { + mlog(0, "LKM_VALBLK passed by caller\n"); + + /* LVB requests for non PR, PW or EX locks are + * ignored. */ + if (mode < LKM_PRMODE) + flags &= ~LKM_VALBLK; + else { + flags |= LKM_GET_LVB; + lock->lksb->flags |= DLM_LKSB_GET_LVB; + } + } + + if (res->owner == dlm->node_num) + status = dlmlock_master(dlm, res, lock, flags); + else + status = dlmlock_remote(dlm, res, lock, flags); + + if (status == DLM_RECOVERING || status == DLM_MIGRATING || + status == DLM_FORWARD) { + mlog(0, "retrying lock with migration/" + "recovery/in progress\n"); + msleep(100); + dlm_wait_for_recovery(dlm); + goto retry_lock; + } + + if (status != DLM_NORMAL) { + lock->lksb->flags &= ~DLM_LKSB_GET_LVB; + if (status != DLM_NOTQUEUED) + dlm_error(status); + goto error; + } + } + +error: + if (status != DLM_NORMAL) { + if (lock && !convert) + dlm_lock_put(lock); + // this is kind of unnecessary + lksb->status = status; + } + + /* put lockres ref from the convert path + * or from dlm_get_lock_resource */ + if (res) + dlm_lockres_put(res); + + return status; +} +EXPORT_SYMBOL_GPL(dlmlock); diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c new file mode 100644 index 0000000..0472795 --- /dev/null +++ b/fs/ocfs2/dlm/dlmmaster.c @@ -0,0 +1,2666 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmmod.c + * + * standalone DLM module + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + + +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/highmem.h> +#include <linux/utsname.h> +#include <linux/init.h> +#include <linux/sysctl.h> +#include <linux/random.h> +#include <linux/blkdev.h> +#include <linux/socket.h> +#include <linux/inet.h> +#include <linux/spinlock.h> +#include <linux/delay.h> + + +#include "cluster/heartbeat.h" +#include "cluster/nodemanager.h" +#include "cluster/tcp.h" + +#include "dlmapi.h" +#include "dlmcommon.h" +#include "dlmdebug.h" + +#define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_MASTER) +#include "cluster/masklog.h" + +enum dlm_mle_type { + DLM_MLE_BLOCK, + DLM_MLE_MASTER, + DLM_MLE_MIGRATION +}; + +struct dlm_lock_name +{ + u8 len; + u8 name[DLM_LOCKID_NAME_MAX]; +}; + +struct dlm_master_list_entry +{ + struct list_head list; + struct list_head hb_events; + struct dlm_ctxt *dlm; + spinlock_t spinlock; + wait_queue_head_t wq; + atomic_t woken; + struct kref mle_refs; + unsigned long maybe_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; + unsigned long vote_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; + unsigned long response_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; + unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; + u8 master; + u8 new_master; + enum dlm_mle_type type; + struct o2hb_callback_func mle_hb_up; + struct o2hb_callback_func mle_hb_down; + union { + struct dlm_lock_resource *res; + struct dlm_lock_name name; + } u; +}; + +static void dlm_mle_node_down(struct dlm_ctxt *dlm, + struct dlm_master_list_entry *mle, + struct o2nm_node *node, + int idx); +static void dlm_mle_node_up(struct dlm_ctxt *dlm, + struct dlm_master_list_entry *mle, + struct o2nm_node *node, + int idx); + +static void dlm_assert_master_worker(struct dlm_work_item *item, void *data); +static int dlm_do_assert_master(struct dlm_ctxt *dlm, const char *lockname, + unsigned int namelen, void *nodemap, + u32 flags); + +static inline int dlm_mle_equal(struct dlm_ctxt *dlm, + struct dlm_master_list_entry *mle, + const char *name, + unsigned int namelen) +{ + struct dlm_lock_resource *res; + + if (dlm != mle->dlm) + return 0; + + if (mle->type == DLM_MLE_BLOCK || + mle->type == DLM_MLE_MIGRATION) { + if (namelen != mle->u.name.len || + memcmp(name, mle->u.name.name, namelen)!=0) + return 0; + } else { + res = mle->u.res; + if (namelen != res->lockname.len || + memcmp(res->lockname.name, name, namelen) != 0) + return 0; + } + return 1; +} + +#if 0 +/* Code here is included but defined out as it aids debugging */ + +void dlm_print_one_mle(struct dlm_master_list_entry *mle) +{ + int i = 0, refs; + char *type; + char attached; + u8 master; + unsigned int namelen; + const char *name; + struct kref *k; + + k = &mle->mle_refs; + if (mle->type == DLM_MLE_BLOCK) + type = "BLK"; + else if (mle->type == DLM_MLE_MASTER) + type = "MAS"; + else + type = "MIG"; + refs = atomic_read(&k->refcount); + master = mle->master; + attached = (list_empty(&mle->hb_events) ? 'N' : 'Y'); + + if (mle->type != DLM_MLE_MASTER) { + namelen = mle->u.name.len; + name = mle->u.name.name; + } else { + namelen = mle->u.res->lockname.len; + name = mle->u.res->lockname.name; + } + + mlog(ML_NOTICE, " #%3d: %3s %3d %3u %3u %c (%d)%.*s\n", + i, type, refs, master, mle->new_master, attached, + namelen, namelen, name); +} + +static void dlm_dump_mles(struct dlm_ctxt *dlm) +{ + struct dlm_master_list_entry *mle; + struct list_head *iter; + + mlog(ML_NOTICE, "dumping all mles for domain %s:\n", dlm->name); + mlog(ML_NOTICE, " ####: type refs owner new events? lockname nodemap votemap respmap maybemap\n"); + spin_lock(&dlm->master_lock); + list_for_each(iter, &dlm->master_list) { + mle = list_entry(iter, struct dlm_master_list_entry, list); + dlm_print_one_mle(mle); + } + spin_unlock(&dlm->master_lock); +} + +extern spinlock_t dlm_domain_lock; +extern struct list_head dlm_domains; + +int dlm_dump_all_mles(const char __user *data, unsigned int len) +{ + struct list_head *iter; + struct dlm_ctxt *dlm; + + spin_lock(&dlm_domain_lock); + list_for_each(iter, &dlm_domains) { + dlm = list_entry (iter, struct dlm_ctxt, list); + mlog(ML_NOTICE, "found dlm: %p, name=%s\n", dlm, dlm->name); + dlm_dump_mles(dlm); + } + spin_unlock(&dlm_domain_lock); + return len; +} +EXPORT_SYMBOL_GPL(dlm_dump_all_mles); + +#endif /* 0 */ + + +static kmem_cache_t *dlm_mle_cache = NULL; + + +static void dlm_mle_release(struct kref *kref); +static void dlm_init_mle(struct dlm_master_list_entry *mle, + enum dlm_mle_type type, + struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + const char *name, + unsigned int namelen); +static void dlm_put_mle(struct dlm_master_list_entry *mle); +static void __dlm_put_mle(struct dlm_master_list_entry *mle); +static int dlm_find_mle(struct dlm_ctxt *dlm, + struct dlm_master_list_entry **mle, + char *name, unsigned int namelen); + +static int dlm_do_master_request(struct dlm_master_list_entry *mle, int to); + + +static int dlm_wait_for_lock_mastery(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_master_list_entry *mle, + int *blocked); +static int dlm_restart_lock_mastery(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_master_list_entry *mle, + int blocked); +static int dlm_add_migration_mle(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_master_list_entry *mle, + struct dlm_master_list_entry **oldmle, + const char *name, unsigned int namelen, + u8 new_master, u8 master); + +static u8 dlm_pick_migration_target(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res); +static void dlm_remove_nonlocal_locks(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res); +static int dlm_mark_lockres_migrating(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 target); + + +int dlm_is_host_down(int errno) +{ + switch (errno) { + case -EBADF: + case -ECONNREFUSED: + case -ENOTCONN: + case -ECONNRESET: + case -EPIPE: + case -EHOSTDOWN: + case -EHOSTUNREACH: + case -ETIMEDOUT: + case -ECONNABORTED: + case -ENETDOWN: + case -ENETUNREACH: + case -ENETRESET: + case -ESHUTDOWN: + case -ENOPROTOOPT: + case -EINVAL: /* if returned from our tcp code, + this means there is no socket */ + return 1; + } + return 0; +} + + +/* + * MASTER LIST FUNCTIONS + */ + + +/* + * regarding master list entries and heartbeat callbacks: + * + * in order to avoid sleeping and allocation that occurs in + * heartbeat, master list entries are simply attached to the + * dlm's established heartbeat callbacks. the mle is attached + * when it is created, and since the dlm->spinlock is held at + * that time, any heartbeat event will be properly discovered + * by the mle. the mle needs to be detached from the + * dlm->mle_hb_events list as soon as heartbeat events are no + * longer useful to the mle, and before the mle is freed. + * + * as a general rule, heartbeat events are no longer needed by + * the mle once an "answer" regarding the lock master has been + * received. + */ +static inline void __dlm_mle_attach_hb_events(struct dlm_ctxt *dlm, + struct dlm_master_list_entry *mle) +{ + assert_spin_locked(&dlm->spinlock); + + list_add_tail(&mle->hb_events, &dlm->mle_hb_events); +} + + +static inline void __dlm_mle_detach_hb_events(struct dlm_ctxt *dlm, + struct dlm_master_list_entry *mle) +{ + if (!list_empty(&mle->hb_events)) + list_del_init(&mle->hb_events); +} + + +static inline void dlm_mle_detach_hb_events(struct dlm_ctxt *dlm, + struct dlm_master_list_entry *mle) +{ + spin_lock(&dlm->spinlock); + __dlm_mle_detach_hb_events(dlm, mle); + spin_unlock(&dlm->spinlock); +} + +/* remove from list and free */ +static void __dlm_put_mle(struct dlm_master_list_entry *mle) +{ + struct dlm_ctxt *dlm; + dlm = mle->dlm; + + assert_spin_locked(&dlm->spinlock); + assert_spin_locked(&dlm->master_lock); + BUG_ON(!atomic_read(&mle->mle_refs.refcount)); + + kref_put(&mle->mle_refs, dlm_mle_release); +} + + +/* must not have any spinlocks coming in */ +static void dlm_put_mle(struct dlm_master_list_entry *mle) +{ + struct dlm_ctxt *dlm; + dlm = mle->dlm; + + spin_lock(&dlm->spinlock); + spin_lock(&dlm->master_lock); + __dlm_put_mle(mle); + spin_unlock(&dlm->master_lock); + spin_unlock(&dlm->spinlock); +} + +static inline void dlm_get_mle(struct dlm_master_list_entry *mle) +{ + kref_get(&mle->mle_refs); +} + +static void dlm_init_mle(struct dlm_master_list_entry *mle, + enum dlm_mle_type type, + struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + const char *name, + unsigned int namelen) +{ + assert_spin_locked(&dlm->spinlock); + + mle->dlm = dlm; + mle->type = type; + INIT_LIST_HEAD(&mle->list); + INIT_LIST_HEAD(&mle->hb_events); + memset(mle->maybe_map, 0, sizeof(mle->maybe_map)); + spin_lock_init(&mle->spinlock); + init_waitqueue_head(&mle->wq); + atomic_set(&mle->woken, 0); + kref_init(&mle->mle_refs); + memset(mle->response_map, 0, sizeof(mle->response_map)); + mle->master = O2NM_MAX_NODES; + mle->new_master = O2NM_MAX_NODES; + + if (mle->type == DLM_MLE_MASTER) { + BUG_ON(!res); + mle->u.res = res; + } else if (mle->type == DLM_MLE_BLOCK) { + BUG_ON(!name); + memcpy(mle->u.name.name, name, namelen); + mle->u.name.len = namelen; + } else /* DLM_MLE_MIGRATION */ { + BUG_ON(!name); + memcpy(mle->u.name.name, name, namelen); + mle->u.name.len = namelen; + } + + /* copy off the node_map and register hb callbacks on our copy */ + memcpy(mle->node_map, dlm->domain_map, sizeof(mle->node_map)); + memcpy(mle->vote_map, dlm->domain_map, sizeof(mle->vote_map)); + clear_bit(dlm->node_num, mle->vote_map); + clear_bit(dlm->node_num, mle->node_map); + + /* attach the mle to the domain node up/down events */ + __dlm_mle_attach_hb_events(dlm, mle); +} + + +/* returns 1 if found, 0 if not */ +static int dlm_find_mle(struct dlm_ctxt *dlm, + struct dlm_master_list_entry **mle, + char *name, unsigned int namelen) +{ + struct dlm_master_list_entry *tmpmle; + struct list_head *iter; + + assert_spin_locked(&dlm->master_lock); + + list_for_each(iter, &dlm->master_list) { + tmpmle = list_entry(iter, struct dlm_master_list_entry, list); + if (!dlm_mle_equal(dlm, tmpmle, name, namelen)) + continue; + dlm_get_mle(tmpmle); + *mle = tmpmle; + return 1; + } + return 0; +} + +void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up) +{ + struct dlm_master_list_entry *mle; + struct list_head *iter; + + assert_spin_locked(&dlm->spinlock); + + list_for_each(iter, &dlm->mle_hb_events) { + mle = list_entry(iter, struct dlm_master_list_entry, + hb_events); + if (node_up) + dlm_mle_node_up(dlm, mle, NULL, idx); + else + dlm_mle_node_down(dlm, mle, NULL, idx); + } +} + +static void dlm_mle_node_down(struct dlm_ctxt *dlm, + struct dlm_master_list_entry *mle, + struct o2nm_node *node, int idx) +{ + spin_lock(&mle->spinlock); + + if (!test_bit(idx, mle->node_map)) + mlog(0, "node %u already removed from nodemap!\n", idx); + else + clear_bit(idx, mle->node_map); + + spin_unlock(&mle->spinlock); +} + +static void dlm_mle_node_up(struct dlm_ctxt *dlm, + struct dlm_master_list_entry *mle, + struct o2nm_node *node, int idx) +{ + spin_lock(&mle->spinlock); + + if (test_bit(idx, mle->node_map)) + mlog(0, "node %u already in node map!\n", idx); + else + set_bit(idx, mle->node_map); + + spin_unlock(&mle->spinlock); +} + + +int dlm_init_mle_cache(void) +{ + dlm_mle_cache = kmem_cache_create("dlm_mle_cache", + sizeof(struct dlm_master_list_entry), + 0, SLAB_HWCACHE_ALIGN, + NULL, NULL); + if (dlm_mle_cache == NULL) + return -ENOMEM; + return 0; +} + +void dlm_destroy_mle_cache(void) +{ + if (dlm_mle_cache) + kmem_cache_destroy(dlm_mle_cache); +} + +static void dlm_mle_release(struct kref *kref) +{ + struct dlm_master_list_entry *mle; + struct dlm_ctxt *dlm; + + mlog_entry_void(); + + mle = container_of(kref, struct dlm_master_list_entry, mle_refs); + dlm = mle->dlm; + + if (mle->type != DLM_MLE_MASTER) { + mlog(0, "calling mle_release for %.*s, type %d\n", + mle->u.name.len, mle->u.name.name, mle->type); + } else { + mlog(0, "calling mle_release for %.*s, type %d\n", + mle->u.res->lockname.len, + mle->u.res->lockname.name, mle->type); + } + assert_spin_locked(&dlm->spinlock); + assert_spin_locked(&dlm->master_lock); + + /* remove from list if not already */ + if (!list_empty(&mle->list)) + list_del_init(&mle->list); + + /* detach the mle from the domain node up/down events */ + __dlm_mle_detach_hb_events(dlm, mle); + + /* NOTE: kfree under spinlock here. + * if this is bad, we can move this to a freelist. */ + kmem_cache_free(dlm_mle_cache, mle); +} + + +/* + * LOCK RESOURCE FUNCTIONS + */ + +static void dlm_set_lockres_owner(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 owner) +{ + assert_spin_locked(&res->spinlock); + + mlog_entry("%.*s, %u\n", res->lockname.len, res->lockname.name, owner); + + if (owner == dlm->node_num) + atomic_inc(&dlm->local_resources); + else if (owner == DLM_LOCK_RES_OWNER_UNKNOWN) + atomic_inc(&dlm->unknown_resources); + else + atomic_inc(&dlm->remote_resources); + + res->owner = owner; +} + +void dlm_change_lockres_owner(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, u8 owner) +{ + assert_spin_locked(&res->spinlock); + + if (owner == res->owner) + return; + + if (res->owner == dlm->node_num) + atomic_dec(&dlm->local_resources); + else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) + atomic_dec(&dlm->unknown_resources); + else + atomic_dec(&dlm->remote_resources); + + dlm_set_lockres_owner(dlm, res, owner); +} + + +static void dlm_lockres_release(struct kref *kref) +{ + struct dlm_lock_resource *res; + + res = container_of(kref, struct dlm_lock_resource, refs); + + /* This should not happen -- all lockres' have a name + * associated with them at init time. */ + BUG_ON(!res->lockname.name); + + mlog(0, "destroying lockres %.*s\n", res->lockname.len, + res->lockname.name); + + /* By the time we're ready to blow this guy away, we shouldn't + * be on any lists. */ + BUG_ON(!list_empty(&res->list)); + BUG_ON(!list_empty(&res->granted)); + BUG_ON(!list_empty(&res->converting)); + BUG_ON(!list_empty(&res->blocked)); + BUG_ON(!list_empty(&res->dirty)); + BUG_ON(!list_empty(&res->recovering)); + BUG_ON(!list_empty(&res->purge)); + + kfree(res->lockname.name); + + kfree(res); +} + +void dlm_lockres_get(struct dlm_lock_resource *res) +{ + kref_get(&res->refs); +} + +void dlm_lockres_put(struct dlm_lock_resource *res) +{ + kref_put(&res->refs, dlm_lockres_release); +} + +static void dlm_init_lockres(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + const char *name, unsigned int namelen) +{ + char *qname; + + /* If we memset here, we lose our reference to the kmalloc'd + * res->lockname.name, so be sure to init every field + * correctly! */ + + qname = (char *) res->lockname.name; + memcpy(qname, name, namelen); + + res->lockname.len = namelen; + res->lockname.hash = full_name_hash(name, namelen); + + init_waitqueue_head(&res->wq); + spin_lock_init(&res->spinlock); + INIT_LIST_HEAD(&res->list); + INIT_LIST_HEAD(&res->granted); + INIT_LIST_HEAD(&res->converting); + INIT_LIST_HEAD(&res->blocked); + INIT_LIST_HEAD(&res->dirty); + INIT_LIST_HEAD(&res->recovering); + INIT_LIST_HEAD(&res->purge); + atomic_set(&res->asts_reserved, 0); + res->migration_pending = 0; + + kref_init(&res->refs); + + /* just for consistency */ + spin_lock(&res->spinlock); + dlm_set_lockres_owner(dlm, res, DLM_LOCK_RES_OWNER_UNKNOWN); + spin_unlock(&res->spinlock); + + res->state = DLM_LOCK_RES_IN_PROGRESS; + + res->last_used = 0; + + memset(res->lvb, 0, DLM_LVB_LEN); +} + +struct dlm_lock_resource *dlm_new_lockres(struct dlm_ctxt *dlm, + const char *name, + unsigned int namelen) +{ + struct dlm_lock_resource *res; + + res = kmalloc(sizeof(struct dlm_lock_resource), GFP_KERNEL); + if (!res) + return NULL; + + res->lockname.name = kmalloc(namelen, GFP_KERNEL); + if (!res->lockname.name) { + kfree(res); + return NULL; + } + + dlm_init_lockres(dlm, res, name, namelen); + return res; +} + +/* + * lookup a lock resource by name. + * may already exist in the hashtable. + * lockid is null terminated + * + * if not, allocate enough for the lockres and for + * the temporary structure used in doing the mastering. + * + * also, do a lookup in the dlm->master_list to see + * if another node has begun mastering the same lock. + * if so, there should be a block entry in there + * for this name, and we should *not* attempt to master + * the lock here. need to wait around for that node + * to assert_master (or die). + * + */ +struct dlm_lock_resource * dlm_get_lock_resource(struct dlm_ctxt *dlm, + const char *lockid, + int flags) +{ + struct dlm_lock_resource *tmpres=NULL, *res=NULL; + struct dlm_master_list_entry *mle = NULL; + struct dlm_master_list_entry *alloc_mle = NULL; + int blocked = 0; + int ret, nodenum; + struct dlm_node_iter iter; + unsigned int namelen; + int tries = 0; + + BUG_ON(!lockid); + + namelen = strlen(lockid); + + mlog(0, "get lockres %s (len %d)\n", lockid, namelen); + +lookup: + spin_lock(&dlm->spinlock); + tmpres = __dlm_lookup_lockres(dlm, lockid, namelen); + if (tmpres) { + spin_unlock(&dlm->spinlock); + mlog(0, "found in hash!\n"); + if (res) + dlm_lockres_put(res); + res = tmpres; + goto leave; + } + + if (!res) { + spin_unlock(&dlm->spinlock); + mlog(0, "allocating a new resource\n"); + /* nothing found and we need to allocate one. */ + alloc_mle = (struct dlm_master_list_entry *) + kmem_cache_alloc(dlm_mle_cache, GFP_KERNEL); + if (!alloc_mle) + goto leave; + res = dlm_new_lockres(dlm, lockid, namelen); + if (!res) + goto leave; + goto lookup; + } + + mlog(0, "no lockres found, allocated our own: %p\n", res); + + if (flags & LKM_LOCAL) { + /* caller knows it's safe to assume it's not mastered elsewhere + * DONE! return right away */ + spin_lock(&res->spinlock); + dlm_change_lockres_owner(dlm, res, dlm->node_num); + __dlm_insert_lockres(dlm, res); + spin_unlock(&res->spinlock); + spin_unlock(&dlm->spinlock); + /* lockres still marked IN_PROGRESS */ + goto wake_waiters; + } + + /* check master list to see if another node has started mastering it */ + spin_lock(&dlm->master_lock); + + /* if we found a block, wait for lock to be mastered by another node */ + blocked = dlm_find_mle(dlm, &mle, (char *)lockid, namelen); + if (blocked) { + if (mle->type == DLM_MLE_MASTER) { + mlog(ML_ERROR, "master entry for nonexistent lock!\n"); + BUG(); + } else if (mle->type == DLM_MLE_MIGRATION) { + /* migration is in progress! */ + /* the good news is that we now know the + * "current" master (mle->master). */ + + spin_unlock(&dlm->master_lock); + assert_spin_locked(&dlm->spinlock); + + /* set the lockres owner and hash it */ + spin_lock(&res->spinlock); + dlm_set_lockres_owner(dlm, res, mle->master); + __dlm_insert_lockres(dlm, res); + spin_unlock(&res->spinlock); + spin_unlock(&dlm->spinlock); + + /* master is known, detach */ + dlm_mle_detach_hb_events(dlm, mle); + dlm_put_mle(mle); + mle = NULL; + goto wake_waiters; + } + } else { + /* go ahead and try to master lock on this node */ + mle = alloc_mle; + /* make sure this does not get freed below */ + alloc_mle = NULL; + dlm_init_mle(mle, DLM_MLE_MASTER, dlm, res, NULL, 0); + set_bit(dlm->node_num, mle->maybe_map); + list_add(&mle->list, &dlm->master_list); + } + + /* at this point there is either a DLM_MLE_BLOCK or a + * DLM_MLE_MASTER on the master list, so it's safe to add the + * lockres to the hashtable. anyone who finds the lock will + * still have to wait on the IN_PROGRESS. */ + + /* finally add the lockres to its hash bucket */ + __dlm_insert_lockres(dlm, res); + /* get an extra ref on the mle in case this is a BLOCK + * if so, the creator of the BLOCK may try to put the last + * ref at this time in the assert master handler, so we + * need an extra one to keep from a bad ptr deref. */ + dlm_get_mle(mle); + spin_unlock(&dlm->master_lock); + spin_unlock(&dlm->spinlock); + + /* must wait for lock to be mastered elsewhere */ + if (blocked) + goto wait; + +redo_request: + ret = -EINVAL; + dlm_node_iter_init(mle->vote_map, &iter); + while ((nodenum = dlm_node_iter_next(&iter)) >= 0) { + ret = dlm_do_master_request(mle, nodenum); + if (ret < 0) + mlog_errno(ret); + if (mle->master != O2NM_MAX_NODES) { + /* found a master ! */ + break; + } + } + +wait: + /* keep going until the response map includes all nodes */ + ret = dlm_wait_for_lock_mastery(dlm, res, mle, &blocked); + if (ret < 0) { + mlog(0, "%s:%.*s: node map changed, redo the " + "master request now, blocked=%d\n", + dlm->name, res->lockname.len, + res->lockname.name, blocked); + if (++tries > 20) { + mlog(ML_ERROR, "%s:%.*s: spinning on " + "dlm_wait_for_lock_mastery, blocked=%d\n", + dlm->name, res->lockname.len, + res->lockname.name, blocked); + dlm_print_one_lock_resource(res); + /* dlm_print_one_mle(mle); */ + tries = 0; + } + goto redo_request; + } + + mlog(0, "lockres mastered by %u\n", res->owner); + /* make sure we never continue without this */ + BUG_ON(res->owner == O2NM_MAX_NODES); + + /* master is known, detach if not already detached */ + dlm_mle_detach_hb_events(dlm, mle); + dlm_put_mle(mle); + /* put the extra ref */ + dlm_put_mle(mle); + +wake_waiters: + spin_lock(&res->spinlock); + res->state &= ~DLM_LOCK_RES_IN_PROGRESS; + spin_unlock(&res->spinlock); + wake_up(&res->wq); + +leave: + /* need to free the unused mle */ + if (alloc_mle) + kmem_cache_free(dlm_mle_cache, alloc_mle); + + return res; +} + + +#define DLM_MASTERY_TIMEOUT_MS 5000 + +static int dlm_wait_for_lock_mastery(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_master_list_entry *mle, + int *blocked) +{ + u8 m; + int ret, bit; + int map_changed, voting_done; + int assert, sleep; + +recheck: + ret = 0; + assert = 0; + + /* check if another node has already become the owner */ + spin_lock(&res->spinlock); + if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN) { + spin_unlock(&res->spinlock); + goto leave; + } + spin_unlock(&res->spinlock); + + spin_lock(&mle->spinlock); + m = mle->master; + map_changed = (memcmp(mle->vote_map, mle->node_map, + sizeof(mle->vote_map)) != 0); + voting_done = (memcmp(mle->vote_map, mle->response_map, + sizeof(mle->vote_map)) == 0); + + /* restart if we hit any errors */ + if (map_changed) { + int b; + mlog(0, "%s: %.*s: node map changed, restarting\n", + dlm->name, res->lockname.len, res->lockname.name); + ret = dlm_restart_lock_mastery(dlm, res, mle, *blocked); + b = (mle->type == DLM_MLE_BLOCK); + if ((*blocked && !b) || (!*blocked && b)) { + mlog(0, "%s:%.*s: status change: old=%d new=%d\n", + dlm->name, res->lockname.len, res->lockname.name, + *blocked, b); + *blocked = b; + } + spin_unlock(&mle->spinlock); + if (ret < 0) { + mlog_errno(ret); + goto leave; + } + mlog(0, "%s:%.*s: restart lock mastery succeeded, " + "rechecking now\n", dlm->name, res->lockname.len, + res->lockname.name); + goto recheck; + } + + if (m != O2NM_MAX_NODES) { + /* another node has done an assert! + * all done! */ + sleep = 0; + } else { + sleep = 1; + /* have all nodes responded? */ + if (voting_done && !*blocked) { + bit = find_next_bit(mle->maybe_map, O2NM_MAX_NODES, 0); + if (dlm->node_num <= bit) { + /* my node number is lowest. + * now tell other nodes that I am + * mastering this. */ + mle->master = dlm->node_num; + assert = 1; + sleep = 0; + } + /* if voting is done, but we have not received + * an assert master yet, we must sleep */ + } + } + + spin_unlock(&mle->spinlock); + + /* sleep if we haven't finished voting yet */ + if (sleep) { + unsigned long timeo = msecs_to_jiffies(DLM_MASTERY_TIMEOUT_MS); + + /* + if (atomic_read(&mle->mle_refs.refcount) < 2) + mlog(ML_ERROR, "mle (%p) refs=%d, name=%.*s\n", mle, + atomic_read(&mle->mle_refs.refcount), + res->lockname.len, res->lockname.name); + */ + atomic_set(&mle->woken, 0); + (void)wait_event_timeout(mle->wq, + (atomic_read(&mle->woken) == 1), + timeo); + if (res->owner == O2NM_MAX_NODES) { + mlog(0, "waiting again\n"); + goto recheck; + } + mlog(0, "done waiting, master is %u\n", res->owner); + ret = 0; + goto leave; + } + + ret = 0; /* done */ + if (assert) { + m = dlm->node_num; + mlog(0, "about to master %.*s here, this=%u\n", + res->lockname.len, res->lockname.name, m); + ret = dlm_do_assert_master(dlm, res->lockname.name, + res->lockname.len, mle->vote_map, 0); + if (ret) { + /* This is a failure in the network path, + * not in the response to the assert_master + * (any nonzero response is a BUG on this node). + * Most likely a socket just got disconnected + * due to node death. */ + mlog_errno(ret); + } + /* no longer need to restart lock mastery. + * all living nodes have been contacted. */ + ret = 0; + } + + /* set the lockres owner */ + spin_lock(&res->spinlock); + dlm_change_lockres_owner(dlm, res, m); + spin_unlock(&res->spinlock); + +leave: + return ret; +} + +struct dlm_bitmap_diff_iter +{ + int curnode; + unsigned long *orig_bm; + unsigned long *cur_bm; + unsigned long diff_bm[BITS_TO_LONGS(O2NM_MAX_NODES)]; +}; + +enum dlm_node_state_change +{ + NODE_DOWN = -1, + NODE_NO_CHANGE = 0, + NODE_UP +}; + +static void dlm_bitmap_diff_iter_init(struct dlm_bitmap_diff_iter *iter, + unsigned long *orig_bm, + unsigned long *cur_bm) +{ + unsigned long p1, p2; + int i; + + iter->curnode = -1; + iter->orig_bm = orig_bm; + iter->cur_bm = cur_bm; + + for (i = 0; i < BITS_TO_LONGS(O2NM_MAX_NODES); i++) { + p1 = *(iter->orig_bm + i); + p2 = *(iter->cur_bm + i); + iter->diff_bm[i] = (p1 & ~p2) | (p2 & ~p1); + } +} + +static int dlm_bitmap_diff_iter_next(struct dlm_bitmap_diff_iter *iter, + enum dlm_node_state_change *state) +{ + int bit; + + if (iter->curnode >= O2NM_MAX_NODES) + return -ENOENT; + + bit = find_next_bit(iter->diff_bm, O2NM_MAX_NODES, + iter->curnode+1); + if (bit >= O2NM_MAX_NODES) { + iter->curnode = O2NM_MAX_NODES; + return -ENOENT; + } + + /* if it was there in the original then this node died */ + if (test_bit(bit, iter->orig_bm)) + *state = NODE_DOWN; + else + *state = NODE_UP; + + iter->curnode = bit; + return bit; +} + + +static int dlm_restart_lock_mastery(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_master_list_entry *mle, + int blocked) +{ + struct dlm_bitmap_diff_iter bdi; + enum dlm_node_state_change sc; + int node; + int ret = 0; + + mlog(0, "something happened such that the " + "master process may need to be restarted!\n"); + + assert_spin_locked(&mle->spinlock); + + dlm_bitmap_diff_iter_init(&bdi, mle->vote_map, mle->node_map); + node = dlm_bitmap_diff_iter_next(&bdi, &sc); + while (node >= 0) { + if (sc == NODE_UP) { + /* a node came up. easy. might not even need + * to talk to it if its node number is higher + * or if we are already blocked. */ + mlog(0, "node up! %d\n", node); + if (blocked) + goto next; + + if (node > dlm->node_num) { + mlog(0, "node > this node. skipping.\n"); + goto next; + } + + /* redo the master request, but only for the new node */ + mlog(0, "sending request to new node\n"); + clear_bit(node, mle->response_map); + set_bit(node, mle->vote_map); + } else { + mlog(ML_ERROR, "node down! %d\n", node); + + /* if the node wasn't involved in mastery skip it, + * but clear it out from the maps so that it will + * not affect mastery of this lockres */ + clear_bit(node, mle->response_map); + clear_bit(node, mle->vote_map); + if (!test_bit(node, mle->maybe_map)) + goto next; + + /* if we're already blocked on lock mastery, and the + * dead node wasn't the expected master, or there is + * another node in the maybe_map, keep waiting */ + if (blocked) { + int lowest = find_next_bit(mle->maybe_map, + O2NM_MAX_NODES, 0); + + /* act like it was never there */ + clear_bit(node, mle->maybe_map); + + if (node != lowest) + goto next; + + mlog(ML_ERROR, "expected master %u died while " + "this node was blocked waiting on it!\n", + node); + lowest = find_next_bit(mle->maybe_map, + O2NM_MAX_NODES, + lowest+1); + if (lowest < O2NM_MAX_NODES) { + mlog(0, "still blocked. waiting " + "on %u now\n", lowest); + goto next; + } + + /* mle is an MLE_BLOCK, but there is now + * nothing left to block on. we need to return + * all the way back out and try again with + * an MLE_MASTER. dlm_do_local_recovery_cleanup + * has already run, so the mle refcount is ok */ + mlog(0, "no longer blocking. we can " + "try to master this here\n"); + mle->type = DLM_MLE_MASTER; + memset(mle->maybe_map, 0, + sizeof(mle->maybe_map)); + memset(mle->response_map, 0, + sizeof(mle->maybe_map)); + memcpy(mle->vote_map, mle->node_map, + sizeof(mle->node_map)); + mle->u.res = res; + set_bit(dlm->node_num, mle->maybe_map); + + ret = -EAGAIN; + goto next; + } + + clear_bit(node, mle->maybe_map); + if (node > dlm->node_num) + goto next; + + mlog(0, "dead node in map!\n"); + /* yuck. go back and re-contact all nodes + * in the vote_map, removing this node. */ + memset(mle->response_map, 0, + sizeof(mle->response_map)); + } + ret = -EAGAIN; +next: + node = dlm_bitmap_diff_iter_next(&bdi, &sc); + } + return ret; +} + + +/* + * DLM_MASTER_REQUEST_MSG + * + * returns: 0 on success, + * -errno on a network error + * + * on error, the caller should assume the target node is "dead" + * + */ + +static int dlm_do_master_request(struct dlm_master_list_entry *mle, int to) +{ + struct dlm_ctxt *dlm = mle->dlm; + struct dlm_master_request request; + int ret, response=0, resend; + + memset(&request, 0, sizeof(request)); + request.node_idx = dlm->node_num; + + BUG_ON(mle->type == DLM_MLE_MIGRATION); + + if (mle->type != DLM_MLE_MASTER) { + request.namelen = mle->u.name.len; + memcpy(request.name, mle->u.name.name, request.namelen); + } else { + request.namelen = mle->u.res->lockname.len; + memcpy(request.name, mle->u.res->lockname.name, + request.namelen); + } + +again: + ret = o2net_send_message(DLM_MASTER_REQUEST_MSG, dlm->key, &request, + sizeof(request), to, &response); + if (ret < 0) { + if (ret == -ESRCH) { + /* should never happen */ + mlog(ML_ERROR, "TCP stack not ready!\n"); + BUG(); + } else if (ret == -EINVAL) { + mlog(ML_ERROR, "bad args passed to o2net!\n"); + BUG(); + } else if (ret == -ENOMEM) { + mlog(ML_ERROR, "out of memory while trying to send " + "network message! retrying\n"); + /* this is totally crude */ + msleep(50); + goto again; + } else if (!dlm_is_host_down(ret)) { + /* not a network error. bad. */ + mlog_errno(ret); + mlog(ML_ERROR, "unhandled error!"); + BUG(); + } + /* all other errors should be network errors, + * and likely indicate node death */ + mlog(ML_ERROR, "link to %d went down!\n", to); + goto out; + } + + ret = 0; + resend = 0; + spin_lock(&mle->spinlock); + switch (response) { + case DLM_MASTER_RESP_YES: + set_bit(to, mle->response_map); + mlog(0, "node %u is the master, response=YES\n", to); + mle->master = to; + break; + case DLM_MASTER_RESP_NO: + mlog(0, "node %u not master, response=NO\n", to); + set_bit(to, mle->response_map); + break; + case DLM_MASTER_RESP_MAYBE: + mlog(0, "node %u not master, response=MAYBE\n", to); + set_bit(to, mle->response_map); + set_bit(to, mle->maybe_map); + break; + case DLM_MASTER_RESP_ERROR: + mlog(0, "node %u hit an error, resending\n", to); + resend = 1; + response = 0; + break; + default: + mlog(ML_ERROR, "bad response! %u\n", response); + BUG(); + } + spin_unlock(&mle->spinlock); + if (resend) { + /* this is also totally crude */ + msleep(50); + goto again; + } + +out: + return ret; +} + +/* + * locks that can be taken here: + * dlm->spinlock + * res->spinlock + * mle->spinlock + * dlm->master_list + * + * if possible, TRIM THIS DOWN!!! + */ +int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data) +{ + u8 response = DLM_MASTER_RESP_MAYBE; + struct dlm_ctxt *dlm = data; + struct dlm_lock_resource *res; + struct dlm_master_request *request = (struct dlm_master_request *) msg->buf; + struct dlm_master_list_entry *mle = NULL, *tmpmle = NULL; + char *name; + unsigned int namelen; + int found, ret; + int set_maybe; + + if (!dlm_grab(dlm)) + return DLM_MASTER_RESP_NO; + + if (!dlm_domain_fully_joined(dlm)) { + response = DLM_MASTER_RESP_NO; + goto send_response; + } + + name = request->name; + namelen = request->namelen; + + if (namelen > DLM_LOCKID_NAME_MAX) { + response = DLM_IVBUFLEN; + goto send_response; + } + +way_up_top: + spin_lock(&dlm->spinlock); + res = __dlm_lookup_lockres(dlm, name, namelen); + if (res) { + spin_unlock(&dlm->spinlock); + + /* take care of the easy cases up front */ + spin_lock(&res->spinlock); + if (res->state & DLM_LOCK_RES_RECOVERING) { + spin_unlock(&res->spinlock); + mlog(0, "returning DLM_MASTER_RESP_ERROR since res is " + "being recovered\n"); + response = DLM_MASTER_RESP_ERROR; + if (mle) + kmem_cache_free(dlm_mle_cache, mle); + goto send_response; + } + + if (res->owner == dlm->node_num) { + u32 flags = DLM_ASSERT_MASTER_MLE_CLEANUP; + spin_unlock(&res->spinlock); + // mlog(0, "this node is the master\n"); + response = DLM_MASTER_RESP_YES; + if (mle) + kmem_cache_free(dlm_mle_cache, mle); + + /* this node is the owner. + * there is some extra work that needs to + * happen now. the requesting node has + * caused all nodes up to this one to + * create mles. this node now needs to + * go back and clean those up. */ + mlog(0, "%u is the owner of %.*s, cleaning everyone else\n", + dlm->node_num, res->lockname.len, res->lockname.name); + ret = dlm_dispatch_assert_master(dlm, res, 1, + request->node_idx, + flags); + if (ret < 0) { + mlog(ML_ERROR, "failed to dispatch assert " + "master work\n"); + response = DLM_MASTER_RESP_ERROR; + } + goto send_response; + } else if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN) { + spin_unlock(&res->spinlock); + // mlog(0, "node %u is the master\n", res->owner); + response = DLM_MASTER_RESP_NO; + if (mle) + kmem_cache_free(dlm_mle_cache, mle); + goto send_response; + } + + /* ok, there is no owner. either this node is + * being blocked, or it is actively trying to + * master this lock. */ + if (!(res->state & DLM_LOCK_RES_IN_PROGRESS)) { + mlog(ML_ERROR, "lock with no owner should be " + "in-progress!\n"); + BUG(); + } + + // mlog(0, "lockres is in progress...\n"); + spin_lock(&dlm->master_lock); + found = dlm_find_mle(dlm, &tmpmle, name, namelen); + if (!found) { + mlog(ML_ERROR, "no mle found for this lock!\n"); + BUG(); + } + set_maybe = 1; + spin_lock(&tmpmle->spinlock); + if (tmpmle->type == DLM_MLE_BLOCK) { + // mlog(0, "this node is waiting for " + // "lockres to be mastered\n"); + response = DLM_MASTER_RESP_NO; + } else if (tmpmle->type == DLM_MLE_MIGRATION) { + mlog(0, "node %u is master, but trying to migrate to " + "node %u.\n", tmpmle->master, tmpmle->new_master); + if (tmpmle->master == dlm->node_num) { + response = DLM_MASTER_RESP_YES; + mlog(ML_ERROR, "no owner on lockres, but this " + "node is trying to migrate it to %u?!\n", + tmpmle->new_master); + BUG(); + } else { + /* the real master can respond on its own */ + response = DLM_MASTER_RESP_NO; + } + } else if (tmpmle->master != DLM_LOCK_RES_OWNER_UNKNOWN) { + set_maybe = 0; + if (tmpmle->master == dlm->node_num) + response = DLM_MASTER_RESP_YES; + else + response = DLM_MASTER_RESP_NO; + } else { + // mlog(0, "this node is attempting to " + // "master lockres\n"); + response = DLM_MASTER_RESP_MAYBE; + } + if (set_maybe) + set_bit(request->node_idx, tmpmle->maybe_map); + spin_unlock(&tmpmle->spinlock); + + spin_unlock(&dlm->master_lock); + spin_unlock(&res->spinlock); + + /* keep the mle attached to heartbeat events */ + dlm_put_mle(tmpmle); + if (mle) + kmem_cache_free(dlm_mle_cache, mle); + goto send_response; + } + + /* + * lockres doesn't exist on this node + * if there is an MLE_BLOCK, return NO + * if there is an MLE_MASTER, return MAYBE + * otherwise, add an MLE_BLOCK, return NO + */ + spin_lock(&dlm->master_lock); + found = dlm_find_mle(dlm, &tmpmle, name, namelen); + if (!found) { + /* this lockid has never been seen on this node yet */ + // mlog(0, "no mle found\n"); + if (!mle) { + spin_unlock(&dlm->master_lock); + spin_unlock(&dlm->spinlock); + + mle = (struct dlm_master_list_entry *) + kmem_cache_alloc(dlm_mle_cache, GFP_KERNEL); + if (!mle) { + // bad bad bad... this sucks. + response = DLM_MASTER_RESP_ERROR; + goto send_response; + } + spin_lock(&dlm->spinlock); + dlm_init_mle(mle, DLM_MLE_BLOCK, dlm, NULL, + name, namelen); + spin_unlock(&dlm->spinlock); + goto way_up_top; + } + + // mlog(0, "this is second time thru, already allocated, " + // "add the block.\n"); + set_bit(request->node_idx, mle->maybe_map); + list_add(&mle->list, &dlm->master_list); + response = DLM_MASTER_RESP_NO; + } else { + // mlog(0, "mle was found\n"); + set_maybe = 1; + spin_lock(&tmpmle->spinlock); + if (tmpmle->type == DLM_MLE_BLOCK) + response = DLM_MASTER_RESP_NO; + else if (tmpmle->type == DLM_MLE_MIGRATION) { + mlog(0, "migration mle was found (%u->%u)\n", + tmpmle->master, tmpmle->new_master); + if (tmpmle->master == dlm->node_num) { + mlog(ML_ERROR, "no lockres, but migration mle " + "says that this node is master!\n"); + BUG(); + } + /* real master can respond on its own */ + response = DLM_MASTER_RESP_NO; + } else { + if (tmpmle->master == dlm->node_num) { + response = DLM_MASTER_RESP_YES; + set_maybe = 0; + } else + response = DLM_MASTER_RESP_MAYBE; + } + if (set_maybe) + set_bit(request->node_idx, tmpmle->maybe_map); + spin_unlock(&tmpmle->spinlock); + } + spin_unlock(&dlm->master_lock); + spin_unlock(&dlm->spinlock); + + if (found) { + /* keep the mle attached to heartbeat events */ + dlm_put_mle(tmpmle); + } +send_response: + dlm_put(dlm); + return response; +} + +/* + * DLM_ASSERT_MASTER_MSG + */ + + +/* + * NOTE: this can be used for debugging + * can periodically run all locks owned by this node + * and re-assert across the cluster... + */ +static int dlm_do_assert_master(struct dlm_ctxt *dlm, const char *lockname, + unsigned int namelen, void *nodemap, + u32 flags) +{ + struct dlm_assert_master assert; + int to, tmpret; + struct dlm_node_iter iter; + int ret = 0; + + BUG_ON(namelen > O2NM_MAX_NAME_LEN); + + /* note that if this nodemap is empty, it returns 0 */ + dlm_node_iter_init(nodemap, &iter); + while ((to = dlm_node_iter_next(&iter)) >= 0) { + int r = 0; + mlog(0, "sending assert master to %d (%.*s)\n", to, + namelen, lockname); + memset(&assert, 0, sizeof(assert)); + assert.node_idx = dlm->node_num; + assert.namelen = namelen; + memcpy(assert.name, lockname, namelen); + assert.flags = cpu_to_be32(flags); + + tmpret = o2net_send_message(DLM_ASSERT_MASTER_MSG, dlm->key, + &assert, sizeof(assert), to, &r); + if (tmpret < 0) { + mlog(ML_ERROR, "assert_master returned %d!\n", tmpret); + if (!dlm_is_host_down(tmpret)) { + mlog(ML_ERROR, "unhandled error!\n"); + BUG(); + } + /* a node died. finish out the rest of the nodes. */ + mlog(ML_ERROR, "link to %d went down!\n", to); + /* any nonzero status return will do */ + ret = tmpret; + } else if (r < 0) { + /* ok, something horribly messed. kill thyself. */ + mlog(ML_ERROR,"during assert master of %.*s to %u, " + "got %d.\n", namelen, lockname, to, r); + dlm_dump_lock_resources(dlm); + BUG(); + } + } + + return ret; +} + +/* + * locks that can be taken here: + * dlm->spinlock + * res->spinlock + * mle->spinlock + * dlm->master_list + * + * if possible, TRIM THIS DOWN!!! + */ +int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_master_list_entry *mle = NULL; + struct dlm_assert_master *assert = (struct dlm_assert_master *)msg->buf; + struct dlm_lock_resource *res = NULL; + char *name; + unsigned int namelen; + u32 flags; + + if (!dlm_grab(dlm)) + return 0; + + name = assert->name; + namelen = assert->namelen; + flags = be32_to_cpu(assert->flags); + + if (namelen > DLM_LOCKID_NAME_MAX) { + mlog(ML_ERROR, "Invalid name length!"); + goto done; + } + + spin_lock(&dlm->spinlock); + + if (flags) + mlog(0, "assert_master with flags: %u\n", flags); + + /* find the MLE */ + spin_lock(&dlm->master_lock); + if (!dlm_find_mle(dlm, &mle, name, namelen)) { + /* not an error, could be master just re-asserting */ + mlog(0, "just got an assert_master from %u, but no " + "MLE for it! (%.*s)\n", assert->node_idx, + namelen, name); + } else { + int bit = find_next_bit (mle->maybe_map, O2NM_MAX_NODES, 0); + if (bit >= O2NM_MAX_NODES) { + /* not necessarily an error, though less likely. + * could be master just re-asserting. */ + mlog(ML_ERROR, "no bits set in the maybe_map, but %u " + "is asserting! (%.*s)\n", assert->node_idx, + namelen, name); + } else if (bit != assert->node_idx) { + if (flags & DLM_ASSERT_MASTER_MLE_CLEANUP) { + mlog(0, "master %u was found, %u should " + "back off\n", assert->node_idx, bit); + } else { + /* with the fix for bug 569, a higher node + * number winning the mastery will respond + * YES to mastery requests, but this node + * had no way of knowing. let it pass. */ + mlog(ML_ERROR, "%u is the lowest node, " + "%u is asserting. (%.*s) %u must " + "have begun after %u won.\n", bit, + assert->node_idx, namelen, name, bit, + assert->node_idx); + } + } + } + spin_unlock(&dlm->master_lock); + + /* ok everything checks out with the MLE + * now check to see if there is a lockres */ + res = __dlm_lookup_lockres(dlm, name, namelen); + if (res) { + spin_lock(&res->spinlock); + if (res->state & DLM_LOCK_RES_RECOVERING) { + mlog(ML_ERROR, "%u asserting but %.*s is " + "RECOVERING!\n", assert->node_idx, namelen, name); + goto kill; + } + if (!mle) { + if (res->owner != assert->node_idx) { + mlog(ML_ERROR, "assert_master from " + "%u, but current owner is " + "%u! (%.*s)\n", + assert->node_idx, res->owner, + namelen, name); + goto kill; + } + } else if (mle->type != DLM_MLE_MIGRATION) { + if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN) { + /* owner is just re-asserting */ + if (res->owner == assert->node_idx) { + mlog(0, "owner %u re-asserting on " + "lock %.*s\n", assert->node_idx, + namelen, name); + goto ok; + } + mlog(ML_ERROR, "got assert_master from " + "node %u, but %u is the owner! " + "(%.*s)\n", assert->node_idx, + res->owner, namelen, name); + goto kill; + } + if (!(res->state & DLM_LOCK_RES_IN_PROGRESS)) { + mlog(ML_ERROR, "got assert from %u, but lock " + "with no owner should be " + "in-progress! (%.*s)\n", + assert->node_idx, + namelen, name); + goto kill; + } + } else /* mle->type == DLM_MLE_MIGRATION */ { + /* should only be getting an assert from new master */ + if (assert->node_idx != mle->new_master) { + mlog(ML_ERROR, "got assert from %u, but " + "new master is %u, and old master " + "was %u (%.*s)\n", + assert->node_idx, mle->new_master, + mle->master, namelen, name); + goto kill; + } + + } +ok: + spin_unlock(&res->spinlock); + } + spin_unlock(&dlm->spinlock); + + // mlog(0, "woo! got an assert_master from node %u!\n", + // assert->node_idx); + if (mle) { + int extra_ref; + + spin_lock(&mle->spinlock); + extra_ref = !!(mle->type == DLM_MLE_BLOCK + || mle->type == DLM_MLE_MIGRATION); + mle->master = assert->node_idx; + atomic_set(&mle->woken, 1); + wake_up(&mle->wq); + spin_unlock(&mle->spinlock); + + if (mle->type == DLM_MLE_MIGRATION && res) { + mlog(0, "finishing off migration of lockres %.*s, " + "from %u to %u\n", + res->lockname.len, res->lockname.name, + dlm->node_num, mle->new_master); + spin_lock(&res->spinlock); + res->state &= ~DLM_LOCK_RES_MIGRATING; + dlm_change_lockres_owner(dlm, res, mle->new_master); + BUG_ON(res->state & DLM_LOCK_RES_DIRTY); + spin_unlock(&res->spinlock); + } + /* master is known, detach if not already detached */ + dlm_mle_detach_hb_events(dlm, mle); + dlm_put_mle(mle); + + if (extra_ref) { + /* the assert master message now balances the extra + * ref given by the master / migration request message. + * if this is the last put, it will be removed + * from the list. */ + dlm_put_mle(mle); + } + } + +done: + if (res) + dlm_lockres_put(res); + dlm_put(dlm); + return 0; + +kill: + /* kill the caller! */ + spin_unlock(&res->spinlock); + spin_unlock(&dlm->spinlock); + dlm_lockres_put(res); + mlog(ML_ERROR, "Bad message received from another node. Dumping state " + "and killing the other node now! This node is OK and can continue.\n"); + dlm_dump_lock_resources(dlm); + dlm_put(dlm); + return -EINVAL; +} + +int dlm_dispatch_assert_master(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + int ignore_higher, u8 request_from, u32 flags) +{ + struct dlm_work_item *item; + item = kcalloc(1, sizeof(*item), GFP_KERNEL); + if (!item) + return -ENOMEM; + + + /* queue up work for dlm_assert_master_worker */ + dlm_grab(dlm); /* get an extra ref for the work item */ + dlm_init_work_item(dlm, item, dlm_assert_master_worker, NULL); + item->u.am.lockres = res; /* already have a ref */ + /* can optionally ignore node numbers higher than this node */ + item->u.am.ignore_higher = ignore_higher; + item->u.am.request_from = request_from; + item->u.am.flags = flags; + + spin_lock(&dlm->work_lock); + list_add_tail(&item->list, &dlm->work_list); + spin_unlock(&dlm->work_lock); + + schedule_work(&dlm->dispatched_work); + return 0; +} + +static void dlm_assert_master_worker(struct dlm_work_item *item, void *data) +{ + struct dlm_ctxt *dlm = data; + int ret = 0; + struct dlm_lock_resource *res; + unsigned long nodemap[BITS_TO_LONGS(O2NM_MAX_NODES)]; + int ignore_higher; + int bit; + u8 request_from; + u32 flags; + + dlm = item->dlm; + res = item->u.am.lockres; + ignore_higher = item->u.am.ignore_higher; + request_from = item->u.am.request_from; + flags = item->u.am.flags; + + spin_lock(&dlm->spinlock); + memcpy(nodemap, dlm->domain_map, sizeof(nodemap)); + spin_unlock(&dlm->spinlock); + + clear_bit(dlm->node_num, nodemap); + if (ignore_higher) { + /* if is this just to clear up mles for nodes below + * this node, do not send the message to the original + * caller or any node number higher than this */ + clear_bit(request_from, nodemap); + bit = dlm->node_num; + while (1) { + bit = find_next_bit(nodemap, O2NM_MAX_NODES, + bit+1); + if (bit >= O2NM_MAX_NODES) + break; + clear_bit(bit, nodemap); + } + } + + /* this call now finishes out the nodemap + * even if one or more nodes die */ + mlog(0, "worker about to master %.*s here, this=%u\n", + res->lockname.len, res->lockname.name, dlm->node_num); + ret = dlm_do_assert_master(dlm, res->lockname.name, + res->lockname.len, + nodemap, flags); + if (ret < 0) { + /* no need to restart, we are done */ + mlog_errno(ret); + } + + dlm_lockres_put(res); + + mlog(0, "finished with dlm_assert_master_worker\n"); +} + + +/* + * DLM_MIGRATE_LOCKRES + */ + + +int dlm_migrate_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + u8 target) +{ + struct dlm_master_list_entry *mle = NULL; + struct dlm_master_list_entry *oldmle = NULL; + struct dlm_migratable_lockres *mres = NULL; + int ret = -EINVAL; + const char *name; + unsigned int namelen; + int mle_added = 0; + struct list_head *queue, *iter; + int i; + struct dlm_lock *lock; + int empty = 1; + + if (!dlm_grab(dlm)) + return -EINVAL; + + name = res->lockname.name; + namelen = res->lockname.len; + + mlog(0, "migrating %.*s to %u\n", namelen, name, target); + + /* + * ensure this lockres is a proper candidate for migration + */ + spin_lock(&res->spinlock); + if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) { + mlog(0, "cannot migrate lockres with unknown owner!\n"); + spin_unlock(&res->spinlock); + goto leave; + } + if (res->owner != dlm->node_num) { + mlog(0, "cannot migrate lockres this node doesn't own!\n"); + spin_unlock(&res->spinlock); + goto leave; + } + mlog(0, "checking queues...\n"); + queue = &res->granted; + for (i=0; i<3; i++) { + list_for_each(iter, queue) { + lock = list_entry (iter, struct dlm_lock, list); + empty = 0; + if (lock->ml.node == dlm->node_num) { + mlog(0, "found a lock owned by this node " + "still on the %s queue! will not " + "migrate this lockres\n", + i==0 ? "granted" : + (i==1 ? "converting" : "blocked")); + spin_unlock(&res->spinlock); + ret = -ENOTEMPTY; + goto leave; + } + } + queue++; + } + mlog(0, "all locks on this lockres are nonlocal. continuing\n"); + spin_unlock(&res->spinlock); + + /* no work to do */ + if (empty) { + mlog(0, "no locks were found on this lockres! done!\n"); + ret = 0; + goto leave; + } + + /* + * preallocate up front + * if this fails, abort + */ + + ret = -ENOMEM; + mres = (struct dlm_migratable_lockres *) __get_free_page(GFP_KERNEL); + if (!mres) { + mlog_errno(ret); + goto leave; + } + + mle = (struct dlm_master_list_entry *) kmem_cache_alloc(dlm_mle_cache, + GFP_KERNEL); + if (!mle) { + mlog_errno(ret); + goto leave; + } + ret = 0; + + /* + * find a node to migrate the lockres to + */ + + mlog(0, "picking a migration node\n"); + spin_lock(&dlm->spinlock); + /* pick a new node */ + if (!test_bit(target, dlm->domain_map) || + target >= O2NM_MAX_NODES) { + target = dlm_pick_migration_target(dlm, res); + } + mlog(0, "node %u chosen for migration\n", target); + + if (target >= O2NM_MAX_NODES || + !test_bit(target, dlm->domain_map)) { + /* target chosen is not alive */ + ret = -EINVAL; + } + + if (ret) { + spin_unlock(&dlm->spinlock); + goto fail; + } + + mlog(0, "continuing with target = %u\n", target); + + /* + * clear any existing master requests and + * add the migration mle to the list + */ + spin_lock(&dlm->master_lock); + ret = dlm_add_migration_mle(dlm, res, mle, &oldmle, name, + namelen, target, dlm->node_num); + spin_unlock(&dlm->master_lock); + spin_unlock(&dlm->spinlock); + + if (ret == -EEXIST) { + mlog(0, "another process is already migrating it\n"); + goto fail; + } + mle_added = 1; + + /* + * set the MIGRATING flag and flush asts + * if we fail after this we need to re-dirty the lockres + */ + if (dlm_mark_lockres_migrating(dlm, res, target) < 0) { + mlog(ML_ERROR, "tried to migrate %.*s to %u, but " + "the target went down.\n", res->lockname.len, + res->lockname.name, target); + spin_lock(&res->spinlock); + res->state &= ~DLM_LOCK_RES_MIGRATING; + spin_unlock(&res->spinlock); + ret = -EINVAL; + } + +fail: + if (oldmle) { + /* master is known, detach if not already detached */ + dlm_mle_detach_hb_events(dlm, oldmle); + dlm_put_mle(oldmle); + } + + if (ret < 0) { + if (mle_added) { + dlm_mle_detach_hb_events(dlm, mle); + dlm_put_mle(mle); + } else if (mle) { + kmem_cache_free(dlm_mle_cache, mle); + } + goto leave; + } + + /* + * at this point, we have a migration target, an mle + * in the master list, and the MIGRATING flag set on + * the lockres + */ + + + /* get an extra reference on the mle. + * otherwise the assert_master from the new + * master will destroy this. + * also, make sure that all callers of dlm_get_mle + * take both dlm->spinlock and dlm->master_lock */ + spin_lock(&dlm->spinlock); + spin_lock(&dlm->master_lock); + dlm_get_mle(mle); + spin_unlock(&dlm->master_lock); + spin_unlock(&dlm->spinlock); + + /* notify new node and send all lock state */ + /* call send_one_lockres with migration flag. + * this serves as notice to the target node that a + * migration is starting. */ + ret = dlm_send_one_lockres(dlm, res, mres, target, + DLM_MRES_MIGRATION); + + if (ret < 0) { + mlog(0, "migration to node %u failed with %d\n", + target, ret); + /* migration failed, detach and clean up mle */ + dlm_mle_detach_hb_events(dlm, mle); + dlm_put_mle(mle); + dlm_put_mle(mle); + goto leave; + } + + /* at this point, the target sends a message to all nodes, + * (using dlm_do_migrate_request). this node is skipped since + * we had to put an mle in the list to begin the process. this + * node now waits for target to do an assert master. this node + * will be the last one notified, ensuring that the migration + * is complete everywhere. if the target dies while this is + * going on, some nodes could potentially see the target as the + * master, so it is important that my recovery finds the migration + * mle and sets the master to UNKNONWN. */ + + + /* wait for new node to assert master */ + while (1) { + ret = wait_event_interruptible_timeout(mle->wq, + (atomic_read(&mle->woken) == 1), + msecs_to_jiffies(5000)); + + if (ret >= 0) { + if (atomic_read(&mle->woken) == 1 || + res->owner == target) + break; + + mlog(0, "timed out during migration\n"); + } + if (ret == -ERESTARTSYS) { + /* migration failed, detach and clean up mle */ + dlm_mle_detach_hb_events(dlm, mle); + dlm_put_mle(mle); + dlm_put_mle(mle); + goto leave; + } + /* TODO: if node died: stop, clean up, return error */ + } + + /* all done, set the owner, clear the flag */ + spin_lock(&res->spinlock); + dlm_set_lockres_owner(dlm, res, target); + res->state &= ~DLM_LOCK_RES_MIGRATING; + dlm_remove_nonlocal_locks(dlm, res); + spin_unlock(&res->spinlock); + wake_up(&res->wq); + + /* master is known, detach if not already detached */ + dlm_mle_detach_hb_events(dlm, mle); + dlm_put_mle(mle); + ret = 0; + + dlm_lockres_calc_usage(dlm, res); + +leave: + /* re-dirty the lockres if we failed */ + if (ret < 0) + dlm_kick_thread(dlm, res); + + /* TODO: cleanup */ + if (mres) + free_page((unsigned long)mres); + + dlm_put(dlm); + + mlog(0, "returning %d\n", ret); + return ret; +} +EXPORT_SYMBOL_GPL(dlm_migrate_lockres); + +int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock) +{ + int ret; + spin_lock(&dlm->ast_lock); + spin_lock(&lock->spinlock); + ret = (list_empty(&lock->bast_list) && !lock->bast_pending); + spin_unlock(&lock->spinlock); + spin_unlock(&dlm->ast_lock); + return ret; +} + +static int dlm_migration_can_proceed(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 mig_target) +{ + int can_proceed; + spin_lock(&res->spinlock); + can_proceed = !!(res->state & DLM_LOCK_RES_MIGRATING); + spin_unlock(&res->spinlock); + + /* target has died, so make the caller break out of the + * wait_event, but caller must recheck the domain_map */ + spin_lock(&dlm->spinlock); + if (!test_bit(mig_target, dlm->domain_map)) + can_proceed = 1; + spin_unlock(&dlm->spinlock); + return can_proceed; +} + +int dlm_lockres_is_dirty(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) +{ + int ret; + spin_lock(&res->spinlock); + ret = !!(res->state & DLM_LOCK_RES_DIRTY); + spin_unlock(&res->spinlock); + return ret; +} + + +static int dlm_mark_lockres_migrating(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 target) +{ + int ret = 0; + + mlog(0, "dlm_mark_lockres_migrating: %.*s, from %u to %u\n", + res->lockname.len, res->lockname.name, dlm->node_num, + target); + /* need to set MIGRATING flag on lockres. this is done by + * ensuring that all asts have been flushed for this lockres. */ + spin_lock(&res->spinlock); + BUG_ON(res->migration_pending); + res->migration_pending = 1; + /* strategy is to reserve an extra ast then release + * it below, letting the release do all of the work */ + __dlm_lockres_reserve_ast(res); + spin_unlock(&res->spinlock); + + /* now flush all the pending asts.. hang out for a bit */ + dlm_kick_thread(dlm, res); + wait_event(dlm->ast_wq, !dlm_lockres_is_dirty(dlm, res)); + dlm_lockres_release_ast(dlm, res); + + mlog(0, "about to wait on migration_wq, dirty=%s\n", + res->state & DLM_LOCK_RES_DIRTY ? "yes" : "no"); + /* if the extra ref we just put was the final one, this + * will pass thru immediately. otherwise, we need to wait + * for the last ast to finish. */ +again: + ret = wait_event_interruptible_timeout(dlm->migration_wq, + dlm_migration_can_proceed(dlm, res, target), + msecs_to_jiffies(1000)); + if (ret < 0) { + mlog(0, "woken again: migrating? %s, dead? %s\n", + res->state & DLM_LOCK_RES_MIGRATING ? "yes":"no", + test_bit(target, dlm->domain_map) ? "no":"yes"); + } else { + mlog(0, "all is well: migrating? %s, dead? %s\n", + res->state & DLM_LOCK_RES_MIGRATING ? "yes":"no", + test_bit(target, dlm->domain_map) ? "no":"yes"); + } + if (!dlm_migration_can_proceed(dlm, res, target)) { + mlog(0, "trying again...\n"); + goto again; + } + + /* did the target go down or die? */ + spin_lock(&dlm->spinlock); + if (!test_bit(target, dlm->domain_map)) { + mlog(ML_ERROR, "aha. migration target %u just went down\n", + target); + ret = -EHOSTDOWN; + } + spin_unlock(&dlm->spinlock); + + /* + * at this point: + * + * o the DLM_LOCK_RES_MIGRATING flag is set + * o there are no pending asts on this lockres + * o all processes trying to reserve an ast on this + * lockres must wait for the MIGRATING flag to clear + */ + return ret; +} + +/* last step in the migration process. + * original master calls this to free all of the dlm_lock + * structures that used to be for other nodes. */ +static void dlm_remove_nonlocal_locks(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res) +{ + struct list_head *iter, *iter2; + struct list_head *queue = &res->granted; + int i; + struct dlm_lock *lock; + + assert_spin_locked(&res->spinlock); + + BUG_ON(res->owner == dlm->node_num); + + for (i=0; i<3; i++) { + list_for_each_safe(iter, iter2, queue) { + lock = list_entry (iter, struct dlm_lock, list); + if (lock->ml.node != dlm->node_num) { + mlog(0, "putting lock for node %u\n", + lock->ml.node); + /* be extra careful */ + BUG_ON(!list_empty(&lock->ast_list)); + BUG_ON(!list_empty(&lock->bast_list)); + BUG_ON(lock->ast_pending); + BUG_ON(lock->bast_pending); + list_del_init(&lock->list); + dlm_lock_put(lock); + } + } + queue++; + } +} + +/* for now this is not too intelligent. we will + * need stats to make this do the right thing. + * this just finds the first lock on one of the + * queues and uses that node as the target. */ +static u8 dlm_pick_migration_target(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res) +{ + int i; + struct list_head *queue = &res->granted; + struct list_head *iter; + struct dlm_lock *lock; + int nodenum; + + assert_spin_locked(&dlm->spinlock); + + spin_lock(&res->spinlock); + for (i=0; i<3; i++) { + list_for_each(iter, queue) { + /* up to the caller to make sure this node + * is alive */ + lock = list_entry (iter, struct dlm_lock, list); + if (lock->ml.node != dlm->node_num) { + spin_unlock(&res->spinlock); + return lock->ml.node; + } + } + queue++; + } + spin_unlock(&res->spinlock); + mlog(0, "have not found a suitable target yet! checking domain map\n"); + + /* ok now we're getting desperate. pick anyone alive. */ + nodenum = -1; + while (1) { + nodenum = find_next_bit(dlm->domain_map, + O2NM_MAX_NODES, nodenum+1); + mlog(0, "found %d in domain map\n", nodenum); + if (nodenum >= O2NM_MAX_NODES) + break; + if (nodenum != dlm->node_num) { + mlog(0, "picking %d\n", nodenum); + return nodenum; + } + } + + mlog(0, "giving up. no master to migrate to\n"); + return DLM_LOCK_RES_OWNER_UNKNOWN; +} + + + +/* this is called by the new master once all lockres + * data has been received */ +static int dlm_do_migrate_request(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 master, u8 new_master, + struct dlm_node_iter *iter) +{ + struct dlm_migrate_request migrate; + int ret, status = 0; + int nodenum; + + memset(&migrate, 0, sizeof(migrate)); + migrate.namelen = res->lockname.len; + memcpy(migrate.name, res->lockname.name, migrate.namelen); + migrate.new_master = new_master; + migrate.master = master; + + ret = 0; + + /* send message to all nodes, except the master and myself */ + while ((nodenum = dlm_node_iter_next(iter)) >= 0) { + if (nodenum == master || + nodenum == new_master) + continue; + + ret = o2net_send_message(DLM_MIGRATE_REQUEST_MSG, dlm->key, + &migrate, sizeof(migrate), nodenum, + &status); + if (ret < 0) + mlog_errno(ret); + else if (status < 0) { + mlog(0, "migrate request (node %u) returned %d!\n", + nodenum, status); + ret = status; + } + } + + if (ret < 0) + mlog_errno(ret); + + mlog(0, "returning ret=%d\n", ret); + return ret; +} + + +/* if there is an existing mle for this lockres, we now know who the master is. + * (the one who sent us *this* message) we can clear it up right away. + * since the process that put the mle on the list still has a reference to it, + * we can unhash it now, set the master and wake the process. as a result, + * we will have no mle in the list to start with. now we can add an mle for + * the migration and this should be the only one found for those scanning the + * list. */ +int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_lock_resource *res = NULL; + struct dlm_migrate_request *migrate = (struct dlm_migrate_request *) msg->buf; + struct dlm_master_list_entry *mle = NULL, *oldmle = NULL; + const char *name; + unsigned int namelen; + int ret = 0; + + if (!dlm_grab(dlm)) + return -EINVAL; + + name = migrate->name; + namelen = migrate->namelen; + + /* preallocate.. if this fails, abort */ + mle = (struct dlm_master_list_entry *) kmem_cache_alloc(dlm_mle_cache, + GFP_KERNEL); + + if (!mle) { + ret = -ENOMEM; + goto leave; + } + + /* check for pre-existing lock */ + spin_lock(&dlm->spinlock); + res = __dlm_lookup_lockres(dlm, name, namelen); + spin_lock(&dlm->master_lock); + + if (res) { + spin_lock(&res->spinlock); + if (res->state & DLM_LOCK_RES_RECOVERING) { + /* if all is working ok, this can only mean that we got + * a migrate request from a node that we now see as + * dead. what can we do here? drop it to the floor? */ + spin_unlock(&res->spinlock); + mlog(ML_ERROR, "Got a migrate request, but the " + "lockres is marked as recovering!"); + kmem_cache_free(dlm_mle_cache, mle); + ret = -EINVAL; /* need a better solution */ + goto unlock; + } + res->state |= DLM_LOCK_RES_MIGRATING; + spin_unlock(&res->spinlock); + } + + /* ignore status. only nonzero status would BUG. */ + ret = dlm_add_migration_mle(dlm, res, mle, &oldmle, + name, namelen, + migrate->new_master, + migrate->master); + +unlock: + spin_unlock(&dlm->master_lock); + spin_unlock(&dlm->spinlock); + + if (oldmle) { + /* master is known, detach if not already detached */ + dlm_mle_detach_hb_events(dlm, oldmle); + dlm_put_mle(oldmle); + } + + if (res) + dlm_lockres_put(res); +leave: + dlm_put(dlm); + return ret; +} + +/* must be holding dlm->spinlock and dlm->master_lock + * when adding a migration mle, we can clear any other mles + * in the master list because we know with certainty that + * the master is "master". so we remove any old mle from + * the list after setting it's master field, and then add + * the new migration mle. this way we can hold with the rule + * of having only one mle for a given lock name at all times. */ +static int dlm_add_migration_mle(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_master_list_entry *mle, + struct dlm_master_list_entry **oldmle, + const char *name, unsigned int namelen, + u8 new_master, u8 master) +{ + int found; + int ret = 0; + + *oldmle = NULL; + + mlog_entry_void(); + + assert_spin_locked(&dlm->spinlock); + assert_spin_locked(&dlm->master_lock); + + /* caller is responsible for any ref taken here on oldmle */ + found = dlm_find_mle(dlm, oldmle, (char *)name, namelen); + if (found) { + struct dlm_master_list_entry *tmp = *oldmle; + spin_lock(&tmp->spinlock); + if (tmp->type == DLM_MLE_MIGRATION) { + if (master == dlm->node_num) { + /* ah another process raced me to it */ + mlog(0, "tried to migrate %.*s, but some " + "process beat me to it\n", + namelen, name); + ret = -EEXIST; + } else { + /* bad. 2 NODES are trying to migrate! */ + mlog(ML_ERROR, "migration error mle: " + "master=%u new_master=%u // request: " + "master=%u new_master=%u // " + "lockres=%.*s\n", + tmp->master, tmp->new_master, + master, new_master, + namelen, name); + BUG(); + } + } else { + /* this is essentially what assert_master does */ + tmp->master = master; + atomic_set(&tmp->woken, 1); + wake_up(&tmp->wq); + /* remove it from the list so that only one + * mle will be found */ + list_del_init(&tmp->list); + } + spin_unlock(&tmp->spinlock); + } + + /* now add a migration mle to the tail of the list */ + dlm_init_mle(mle, DLM_MLE_MIGRATION, dlm, res, name, namelen); + mle->new_master = new_master; + mle->master = master; + /* do this for consistency with other mle types */ + set_bit(new_master, mle->maybe_map); + list_add(&mle->list, &dlm->master_list); + + return ret; +} + + +void dlm_clean_master_list(struct dlm_ctxt *dlm, u8 dead_node) +{ + struct list_head *iter, *iter2; + struct dlm_master_list_entry *mle; + struct dlm_lock_resource *res; + + mlog_entry("dlm=%s, dead node=%u\n", dlm->name, dead_node); +top: + assert_spin_locked(&dlm->spinlock); + + /* clean the master list */ + spin_lock(&dlm->master_lock); + list_for_each_safe(iter, iter2, &dlm->master_list) { + mle = list_entry(iter, struct dlm_master_list_entry, list); + + BUG_ON(mle->type != DLM_MLE_BLOCK && + mle->type != DLM_MLE_MASTER && + mle->type != DLM_MLE_MIGRATION); + + /* MASTER mles are initiated locally. the waiting + * process will notice the node map change + * shortly. let that happen as normal. */ + if (mle->type == DLM_MLE_MASTER) + continue; + + + /* BLOCK mles are initiated by other nodes. + * need to clean up if the dead node would have + * been the master. */ + if (mle->type == DLM_MLE_BLOCK) { + int bit; + + spin_lock(&mle->spinlock); + bit = find_next_bit(mle->maybe_map, O2NM_MAX_NODES, 0); + if (bit != dead_node) { + mlog(0, "mle found, but dead node %u would " + "not have been master\n", dead_node); + spin_unlock(&mle->spinlock); + } else { + /* must drop the refcount by one since the + * assert_master will never arrive. this + * may result in the mle being unlinked and + * freed, but there may still be a process + * waiting in the dlmlock path which is fine. */ + mlog(ML_ERROR, "node %u was expected master\n", + dead_node); + atomic_set(&mle->woken, 1); + spin_unlock(&mle->spinlock); + wake_up(&mle->wq); + /* final put will take care of list removal */ + __dlm_put_mle(mle); + } + continue; + } + + /* everything else is a MIGRATION mle */ + + /* the rule for MIGRATION mles is that the master + * becomes UNKNOWN if *either* the original or + * the new master dies. all UNKNOWN lockreses + * are sent to whichever node becomes the recovery + * master. the new master is responsible for + * determining if there is still a master for + * this lockres, or if he needs to take over + * mastery. either way, this node should expect + * another message to resolve this. */ + if (mle->master != dead_node && + mle->new_master != dead_node) + continue; + + /* if we have reached this point, this mle needs to + * be removed from the list and freed. */ + + /* remove from the list early. NOTE: unlinking + * list_head while in list_for_each_safe */ + spin_lock(&mle->spinlock); + list_del_init(&mle->list); + atomic_set(&mle->woken, 1); + spin_unlock(&mle->spinlock); + wake_up(&mle->wq); + + mlog(0, "node %u died during migration from " + "%u to %u!\n", dead_node, + mle->master, mle->new_master); + /* if there is a lockres associated with this + * mle, find it and set its owner to UNKNOWN */ + res = __dlm_lookup_lockres(dlm, mle->u.name.name, + mle->u.name.len); + if (res) { + /* unfortunately if we hit this rare case, our + * lock ordering is messed. we need to drop + * the master lock so that we can take the + * lockres lock, meaning that we will have to + * restart from the head of list. */ + spin_unlock(&dlm->master_lock); + + /* move lockres onto recovery list */ + spin_lock(&res->spinlock); + dlm_set_lockres_owner(dlm, res, + DLM_LOCK_RES_OWNER_UNKNOWN); + dlm_move_lockres_to_recovery_list(dlm, res); + spin_unlock(&res->spinlock); + dlm_lockres_put(res); + + /* dump the mle */ + spin_lock(&dlm->master_lock); + __dlm_put_mle(mle); + spin_unlock(&dlm->master_lock); + + /* restart */ + goto top; + } + + /* this may be the last reference */ + __dlm_put_mle(mle); + } + spin_unlock(&dlm->master_lock); +} + + +int dlm_finish_migration(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + u8 old_master) +{ + struct dlm_node_iter iter; + int ret = 0; + + spin_lock(&dlm->spinlock); + dlm_node_iter_init(dlm->domain_map, &iter); + clear_bit(old_master, iter.node_map); + clear_bit(dlm->node_num, iter.node_map); + spin_unlock(&dlm->spinlock); + + mlog(0, "now time to do a migrate request to other nodes\n"); + ret = dlm_do_migrate_request(dlm, res, old_master, + dlm->node_num, &iter); + if (ret < 0) { + mlog_errno(ret); + goto leave; + } + + mlog(0, "doing assert master of %.*s to all except the original node\n", + res->lockname.len, res->lockname.name); + /* this call now finishes out the nodemap + * even if one or more nodes die */ + ret = dlm_do_assert_master(dlm, res->lockname.name, + res->lockname.len, iter.node_map, + DLM_ASSERT_MASTER_FINISH_MIGRATION); + if (ret < 0) { + /* no longer need to retry. all living nodes contacted. */ + mlog_errno(ret); + ret = 0; + } + + memset(iter.node_map, 0, sizeof(iter.node_map)); + set_bit(old_master, iter.node_map); + mlog(0, "doing assert master of %.*s back to %u\n", + res->lockname.len, res->lockname.name, old_master); + ret = dlm_do_assert_master(dlm, res->lockname.name, + res->lockname.len, iter.node_map, + DLM_ASSERT_MASTER_FINISH_MIGRATION); + if (ret < 0) { + mlog(0, "assert master to original master failed " + "with %d.\n", ret); + /* the only nonzero status here would be because of + * a dead original node. we're done. */ + ret = 0; + } + + /* all done, set the owner, clear the flag */ + spin_lock(&res->spinlock); + dlm_set_lockres_owner(dlm, res, dlm->node_num); + res->state &= ~DLM_LOCK_RES_MIGRATING; + spin_unlock(&res->spinlock); + /* re-dirty it on the new master */ + dlm_kick_thread(dlm, res); + wake_up(&res->wq); +leave: + return ret; +} + +/* + * LOCKRES AST REFCOUNT + * this is integral to migration + */ + +/* for future intent to call an ast, reserve one ahead of time. + * this should be called only after waiting on the lockres + * with dlm_wait_on_lockres, and while still holding the + * spinlock after the call. */ +void __dlm_lockres_reserve_ast(struct dlm_lock_resource *res) +{ + assert_spin_locked(&res->spinlock); + if (res->state & DLM_LOCK_RES_MIGRATING) { + __dlm_print_one_lock_resource(res); + } + BUG_ON(res->state & DLM_LOCK_RES_MIGRATING); + + atomic_inc(&res->asts_reserved); +} + +/* + * used to drop the reserved ast, either because it went unused, + * or because the ast/bast was actually called. + * + * also, if there is a pending migration on this lockres, + * and this was the last pending ast on the lockres, + * atomically set the MIGRATING flag before we drop the lock. + * this is how we ensure that migration can proceed with no + * asts in progress. note that it is ok if the state of the + * queues is such that a lock should be granted in the future + * or that a bast should be fired, because the new master will + * shuffle the lists on this lockres as soon as it is migrated. + */ +void dlm_lockres_release_ast(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res) +{ + if (!atomic_dec_and_lock(&res->asts_reserved, &res->spinlock)) + return; + + if (!res->migration_pending) { + spin_unlock(&res->spinlock); + return; + } + + BUG_ON(res->state & DLM_LOCK_RES_MIGRATING); + res->migration_pending = 0; + res->state |= DLM_LOCK_RES_MIGRATING; + spin_unlock(&res->spinlock); + wake_up(&res->wq); + wake_up(&dlm->migration_wq); +} diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c new file mode 100644 index 0000000..0c8eb10 --- /dev/null +++ b/fs/ocfs2/dlm/dlmrecovery.c @@ -0,0 +1,2132 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmrecovery.c + * + * recovery stuff + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + + +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/highmem.h> +#include <linux/utsname.h> +#include <linux/init.h> +#include <linux/sysctl.h> +#include <linux/random.h> +#include <linux/blkdev.h> +#include <linux/socket.h> +#include <linux/inet.h> +#include <linux/timer.h> +#include <linux/kthread.h> + + +#include "cluster/heartbeat.h" +#include "cluster/nodemanager.h" +#include "cluster/tcp.h" + +#include "dlmapi.h" +#include "dlmcommon.h" +#include "dlmdomain.h" + +#define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_RECOVERY) +#include "cluster/masklog.h" + +static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node); + +static int dlm_recovery_thread(void *data); +void dlm_complete_recovery_thread(struct dlm_ctxt *dlm); +int dlm_launch_recovery_thread(struct dlm_ctxt *dlm); +static void dlm_kick_recovery_thread(struct dlm_ctxt *dlm); +static int dlm_do_recovery(struct dlm_ctxt *dlm); + +static int dlm_pick_recovery_master(struct dlm_ctxt *dlm); +static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node); +static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node); +static int dlm_request_all_locks(struct dlm_ctxt *dlm, + u8 request_from, u8 dead_node); +static void dlm_destroy_recovery_area(struct dlm_ctxt *dlm, u8 dead_node); + +static inline int dlm_num_locks_in_lockres(struct dlm_lock_resource *res); +static void dlm_init_migratable_lockres(struct dlm_migratable_lockres *mres, + const char *lockname, int namelen, + int total_locks, u64 cookie, + u8 flags, u8 master); +static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm, + struct dlm_migratable_lockres *mres, + u8 send_to, + struct dlm_lock_resource *res, + int total_locks); +static int dlm_lockres_master_requery(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 *real_master); +static int dlm_process_recovery_data(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_migratable_lockres *mres); +static int dlm_do_master_requery(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 nodenum, u8 *real_master); +static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm); +static int dlm_send_all_done_msg(struct dlm_ctxt *dlm, + u8 dead_node, u8 send_to); +static int dlm_send_begin_reco_message(struct dlm_ctxt *dlm, u8 dead_node); +static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm, + struct list_head *list, u8 dead_node); +static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm, + u8 dead_node, u8 new_master); +static void dlm_reco_ast(void *astdata); +static void dlm_reco_bast(void *astdata, int blocked_type); +static void dlm_reco_unlock_ast(void *astdata, enum dlm_status st); +static void dlm_request_all_locks_worker(struct dlm_work_item *item, + void *data); +static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data); + +static u64 dlm_get_next_mig_cookie(void); + +static spinlock_t dlm_reco_state_lock = SPIN_LOCK_UNLOCKED; +static spinlock_t dlm_mig_cookie_lock = SPIN_LOCK_UNLOCKED; +static u64 dlm_mig_cookie = 1; + +static u64 dlm_get_next_mig_cookie(void) +{ + u64 c; + spin_lock(&dlm_mig_cookie_lock); + c = dlm_mig_cookie; + if (dlm_mig_cookie == (~0ULL)) + dlm_mig_cookie = 1; + else + dlm_mig_cookie++; + spin_unlock(&dlm_mig_cookie_lock); + return c; +} + +static inline void dlm_reset_recovery(struct dlm_ctxt *dlm) +{ + spin_lock(&dlm->spinlock); + clear_bit(dlm->reco.dead_node, dlm->recovery_map); + dlm->reco.dead_node = O2NM_INVALID_NODE_NUM; + dlm->reco.new_master = O2NM_INVALID_NODE_NUM; + spin_unlock(&dlm->spinlock); +} + +/* Worker function used during recovery. */ +void dlm_dispatch_work(void *data) +{ + struct dlm_ctxt *dlm = (struct dlm_ctxt *)data; + LIST_HEAD(tmp_list); + struct list_head *iter, *iter2; + struct dlm_work_item *item; + dlm_workfunc_t *workfunc; + + spin_lock(&dlm->work_lock); + list_splice_init(&dlm->work_list, &tmp_list); + spin_unlock(&dlm->work_lock); + + list_for_each_safe(iter, iter2, &tmp_list) { + item = list_entry(iter, struct dlm_work_item, list); + workfunc = item->func; + list_del_init(&item->list); + + /* already have ref on dlm to avoid having + * it disappear. just double-check. */ + BUG_ON(item->dlm != dlm); + + /* this is allowed to sleep and + * call network stuff */ + workfunc(item, item->data); + + dlm_put(dlm); + kfree(item); + } +} + +/* + * RECOVERY THREAD + */ + +static void dlm_kick_recovery_thread(struct dlm_ctxt *dlm) +{ + /* wake the recovery thread + * this will wake the reco thread in one of three places + * 1) sleeping with no recovery happening + * 2) sleeping with recovery mastered elsewhere + * 3) recovery mastered here, waiting on reco data */ + + wake_up(&dlm->dlm_reco_thread_wq); +} + +/* Launch the recovery thread */ +int dlm_launch_recovery_thread(struct dlm_ctxt *dlm) +{ + mlog(0, "starting dlm recovery thread...\n"); + + dlm->dlm_reco_thread_task = kthread_run(dlm_recovery_thread, dlm, + "dlm_reco_thread"); + if (IS_ERR(dlm->dlm_reco_thread_task)) { + mlog_errno(PTR_ERR(dlm->dlm_reco_thread_task)); + dlm->dlm_reco_thread_task = NULL; + return -EINVAL; + } + + return 0; +} + +void dlm_complete_recovery_thread(struct dlm_ctxt *dlm) +{ + if (dlm->dlm_reco_thread_task) { + mlog(0, "waiting for dlm recovery thread to exit\n"); + kthread_stop(dlm->dlm_reco_thread_task); + dlm->dlm_reco_thread_task = NULL; + } +} + + + +/* + * this is lame, but here's how recovery works... + * 1) all recovery threads cluster wide will work on recovering + * ONE node at a time + * 2) negotiate who will take over all the locks for the dead node. + * thats right... ALL the locks. + * 3) once a new master is chosen, everyone scans all locks + * and moves aside those mastered by the dead guy + * 4) each of these locks should be locked until recovery is done + * 5) the new master collects up all of secondary lock queue info + * one lock at a time, forcing each node to communicate back + * before continuing + * 6) each secondary lock queue responds with the full known lock info + * 7) once the new master has run all its locks, it sends a ALLDONE! + * message to everyone + * 8) upon receiving this message, the secondary queue node unlocks + * and responds to the ALLDONE + * 9) once the new master gets responses from everyone, he unlocks + * everything and recovery for this dead node is done + *10) go back to 2) while there are still dead nodes + * + */ + + +#define DLM_RECO_THREAD_TIMEOUT_MS (5 * 1000) + +static int dlm_recovery_thread(void *data) +{ + int status; + struct dlm_ctxt *dlm = data; + unsigned long timeout = msecs_to_jiffies(DLM_RECO_THREAD_TIMEOUT_MS); + + mlog(0, "dlm thread running for %s...\n", dlm->name); + + while (!kthread_should_stop()) { + if (dlm_joined(dlm)) { + status = dlm_do_recovery(dlm); + if (status == -EAGAIN) { + /* do not sleep, recheck immediately. */ + continue; + } + if (status < 0) + mlog_errno(status); + } + + wait_event_interruptible_timeout(dlm->dlm_reco_thread_wq, + kthread_should_stop(), + timeout); + } + + mlog(0, "quitting DLM recovery thread\n"); + return 0; +} + +/* callers of the top-level api calls (dlmlock/dlmunlock) should + * block on the dlm->reco.event when recovery is in progress. + * the dlm recovery thread will set this state when it begins + * recovering a dead node (as the new master or not) and clear + * the state and wake as soon as all affected lock resources have + * been marked with the RECOVERY flag */ +static int dlm_in_recovery(struct dlm_ctxt *dlm) +{ + int in_recovery; + spin_lock(&dlm->spinlock); + in_recovery = !!(dlm->reco.state & DLM_RECO_STATE_ACTIVE); + spin_unlock(&dlm->spinlock); + return in_recovery; +} + + +void dlm_wait_for_recovery(struct dlm_ctxt *dlm) +{ + wait_event(dlm->reco.event, !dlm_in_recovery(dlm)); +} + +static void dlm_begin_recovery(struct dlm_ctxt *dlm) +{ + spin_lock(&dlm->spinlock); + BUG_ON(dlm->reco.state & DLM_RECO_STATE_ACTIVE); + dlm->reco.state |= DLM_RECO_STATE_ACTIVE; + spin_unlock(&dlm->spinlock); +} + +static void dlm_end_recovery(struct dlm_ctxt *dlm) +{ + spin_lock(&dlm->spinlock); + BUG_ON(!(dlm->reco.state & DLM_RECO_STATE_ACTIVE)); + dlm->reco.state &= ~DLM_RECO_STATE_ACTIVE; + spin_unlock(&dlm->spinlock); + wake_up(&dlm->reco.event); +} + +static int dlm_do_recovery(struct dlm_ctxt *dlm) +{ + int status = 0; + + spin_lock(&dlm->spinlock); + + /* check to see if the new master has died */ + if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM && + test_bit(dlm->reco.new_master, dlm->recovery_map)) { + mlog(0, "new master %u died while recovering %u!\n", + dlm->reco.new_master, dlm->reco.dead_node); + /* unset the new_master, leave dead_node */ + dlm->reco.new_master = O2NM_INVALID_NODE_NUM; + } + + /* select a target to recover */ + if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) { + int bit; + + bit = find_next_bit (dlm->recovery_map, O2NM_MAX_NODES+1, 0); + if (bit >= O2NM_MAX_NODES || bit < 0) + dlm->reco.dead_node = O2NM_INVALID_NODE_NUM; + else + dlm->reco.dead_node = bit; + } else if (!test_bit(dlm->reco.dead_node, dlm->recovery_map)) { + /* BUG? */ + mlog(ML_ERROR, "dead_node %u no longer in recovery map!\n", + dlm->reco.dead_node); + dlm->reco.dead_node = O2NM_INVALID_NODE_NUM; + } + + if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) { + // mlog(0, "nothing to recover! sleeping now!\n"); + spin_unlock(&dlm->spinlock); + /* return to main thread loop and sleep. */ + return 0; + } + mlog(0, "recovery thread found node %u in the recovery map!\n", + dlm->reco.dead_node); + spin_unlock(&dlm->spinlock); + + /* take write barrier */ + /* (stops the list reshuffling thread, proxy ast handling) */ + dlm_begin_recovery(dlm); + + if (dlm->reco.new_master == dlm->node_num) + goto master_here; + + if (dlm->reco.new_master == O2NM_INVALID_NODE_NUM) { + /* choose a new master */ + if (!dlm_pick_recovery_master(dlm)) { + /* already notified everyone. go. */ + dlm->reco.new_master = dlm->node_num; + goto master_here; + } + mlog(0, "another node will master this recovery session.\n"); + } + mlog(0, "dlm=%s, new_master=%u, this node=%u, dead_node=%u\n", + dlm->name, dlm->reco.new_master, + dlm->node_num, dlm->reco.dead_node); + + /* it is safe to start everything back up here + * because all of the dead node's lock resources + * have been marked as in-recovery */ + dlm_end_recovery(dlm); + + /* sleep out in main dlm_recovery_thread loop. */ + return 0; + +master_here: + mlog(0, "mastering recovery of %s:%u here(this=%u)!\n", + dlm->name, dlm->reco.dead_node, dlm->node_num); + + status = dlm_remaster_locks(dlm, dlm->reco.dead_node); + if (status < 0) { + mlog(ML_ERROR, "error %d remastering locks for node %u, " + "retrying.\n", status, dlm->reco.dead_node); + } else { + /* success! see if any other nodes need recovery */ + dlm_reset_recovery(dlm); + } + dlm_end_recovery(dlm); + + /* continue and look for another dead node */ + return -EAGAIN; +} + +static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node) +{ + int status = 0; + struct dlm_reco_node_data *ndata; + struct list_head *iter; + int all_nodes_done; + int destroy = 0; + int pass = 0; + + status = dlm_init_recovery_area(dlm, dead_node); + if (status < 0) + goto leave; + + /* safe to access the node data list without a lock, since this + * process is the only one to change the list */ + list_for_each(iter, &dlm->reco.node_data) { + ndata = list_entry (iter, struct dlm_reco_node_data, list); + BUG_ON(ndata->state != DLM_RECO_NODE_DATA_INIT); + ndata->state = DLM_RECO_NODE_DATA_REQUESTING; + + mlog(0, "requesting lock info from node %u\n", + ndata->node_num); + + if (ndata->node_num == dlm->node_num) { + ndata->state = DLM_RECO_NODE_DATA_DONE; + continue; + } + + status = dlm_request_all_locks(dlm, ndata->node_num, dead_node); + if (status < 0) { + mlog_errno(status); + if (dlm_is_host_down(status)) + ndata->state = DLM_RECO_NODE_DATA_DEAD; + else { + destroy = 1; + goto leave; + } + } + + switch (ndata->state) { + case DLM_RECO_NODE_DATA_INIT: + case DLM_RECO_NODE_DATA_FINALIZE_SENT: + case DLM_RECO_NODE_DATA_REQUESTED: + BUG(); + break; + case DLM_RECO_NODE_DATA_DEAD: + mlog(0, "node %u died after requesting " + "recovery info for node %u\n", + ndata->node_num, dead_node); + // start all over + destroy = 1; + status = -EAGAIN; + goto leave; + case DLM_RECO_NODE_DATA_REQUESTING: + ndata->state = DLM_RECO_NODE_DATA_REQUESTED; + mlog(0, "now receiving recovery data from " + "node %u for dead node %u\n", + ndata->node_num, dead_node); + break; + case DLM_RECO_NODE_DATA_RECEIVING: + mlog(0, "already receiving recovery data from " + "node %u for dead node %u\n", + ndata->node_num, dead_node); + break; + case DLM_RECO_NODE_DATA_DONE: + mlog(0, "already DONE receiving recovery data " + "from node %u for dead node %u\n", + ndata->node_num, dead_node); + break; + } + } + + mlog(0, "done requesting all lock info\n"); + + /* nodes should be sending reco data now + * just need to wait */ + + while (1) { + /* check all the nodes now to see if we are + * done, or if anyone died */ + all_nodes_done = 1; + spin_lock(&dlm_reco_state_lock); + list_for_each(iter, &dlm->reco.node_data) { + ndata = list_entry (iter, struct dlm_reco_node_data, list); + + mlog(0, "checking recovery state of node %u\n", + ndata->node_num); + switch (ndata->state) { + case DLM_RECO_NODE_DATA_INIT: + case DLM_RECO_NODE_DATA_REQUESTING: + mlog(ML_ERROR, "bad ndata state for " + "node %u: state=%d\n", + ndata->node_num, ndata->state); + BUG(); + break; + case DLM_RECO_NODE_DATA_DEAD: + mlog(0, "node %u died after " + "requesting recovery info for " + "node %u\n", ndata->node_num, + dead_node); + spin_unlock(&dlm_reco_state_lock); + // start all over + destroy = 1; + status = -EAGAIN; + goto leave; + case DLM_RECO_NODE_DATA_RECEIVING: + case DLM_RECO_NODE_DATA_REQUESTED: + all_nodes_done = 0; + break; + case DLM_RECO_NODE_DATA_DONE: + break; + case DLM_RECO_NODE_DATA_FINALIZE_SENT: + break; + } + } + spin_unlock(&dlm_reco_state_lock); + + mlog(0, "pass #%d, all_nodes_done?: %s\n", ++pass, + all_nodes_done?"yes":"no"); + if (all_nodes_done) { + int ret; + + /* all nodes are now in DLM_RECO_NODE_DATA_DONE state + * just send a finalize message to everyone and + * clean up */ + mlog(0, "all nodes are done! send finalize\n"); + ret = dlm_send_finalize_reco_message(dlm); + if (ret < 0) + mlog_errno(ret); + + spin_lock(&dlm->spinlock); + dlm_finish_local_lockres_recovery(dlm, dead_node, + dlm->node_num); + spin_unlock(&dlm->spinlock); + mlog(0, "should be done with recovery!\n"); + + mlog(0, "finishing recovery of %s at %lu, " + "dead=%u, this=%u, new=%u\n", dlm->name, + jiffies, dlm->reco.dead_node, + dlm->node_num, dlm->reco.new_master); + destroy = 1; + status = ret; + /* rescan everything marked dirty along the way */ + dlm_kick_thread(dlm, NULL); + break; + } + /* wait to be signalled, with periodic timeout + * to check for node death */ + wait_event_interruptible_timeout(dlm->dlm_reco_thread_wq, + kthread_should_stop(), + msecs_to_jiffies(DLM_RECO_THREAD_TIMEOUT_MS)); + + } + +leave: + if (destroy) + dlm_destroy_recovery_area(dlm, dead_node); + + mlog_exit(status); + return status; +} + +static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node) +{ + int num=0; + struct dlm_reco_node_data *ndata; + + spin_lock(&dlm->spinlock); + memcpy(dlm->reco.node_map, dlm->domain_map, sizeof(dlm->domain_map)); + /* nodes can only be removed (by dying) after dropping + * this lock, and death will be trapped later, so this should do */ + spin_unlock(&dlm->spinlock); + + while (1) { + num = find_next_bit (dlm->reco.node_map, O2NM_MAX_NODES, num); + if (num >= O2NM_MAX_NODES) { + break; + } + BUG_ON(num == dead_node); + + ndata = kcalloc(1, sizeof(*ndata), GFP_KERNEL); + if (!ndata) { + dlm_destroy_recovery_area(dlm, dead_node); + return -ENOMEM; + } + ndata->node_num = num; + ndata->state = DLM_RECO_NODE_DATA_INIT; + spin_lock(&dlm_reco_state_lock); + list_add_tail(&ndata->list, &dlm->reco.node_data); + spin_unlock(&dlm_reco_state_lock); + num++; + } + + return 0; +} + +static void dlm_destroy_recovery_area(struct dlm_ctxt *dlm, u8 dead_node) +{ + struct list_head *iter, *iter2; + struct dlm_reco_node_data *ndata; + LIST_HEAD(tmplist); + + spin_lock(&dlm_reco_state_lock); + list_splice_init(&dlm->reco.node_data, &tmplist); + spin_unlock(&dlm_reco_state_lock); + + list_for_each_safe(iter, iter2, &tmplist) { + ndata = list_entry (iter, struct dlm_reco_node_data, list); + list_del_init(&ndata->list); + kfree(ndata); + } +} + +static int dlm_request_all_locks(struct dlm_ctxt *dlm, u8 request_from, + u8 dead_node) +{ + struct dlm_lock_request lr; + enum dlm_status ret; + + mlog(0, "\n"); + + + mlog(0, "dlm_request_all_locks: dead node is %u, sending request " + "to %u\n", dead_node, request_from); + + memset(&lr, 0, sizeof(lr)); + lr.node_idx = dlm->node_num; + lr.dead_node = dead_node; + + // send message + ret = DLM_NOLOCKMGR; + ret = o2net_send_message(DLM_LOCK_REQUEST_MSG, dlm->key, + &lr, sizeof(lr), request_from, NULL); + + /* negative status is handled by caller */ + if (ret < 0) + mlog_errno(ret); + + // return from here, then + // sleep until all received or error + return ret; + +} + +int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_lock_request *lr = (struct dlm_lock_request *)msg->buf; + char *buf = NULL; + struct dlm_work_item *item = NULL; + + if (!dlm_grab(dlm)) + return -EINVAL; + + BUG_ON(lr->dead_node != dlm->reco.dead_node); + + item = kcalloc(1, sizeof(*item), GFP_KERNEL); + if (!item) { + dlm_put(dlm); + return -ENOMEM; + } + + /* this will get freed by dlm_request_all_locks_worker */ + buf = (char *) __get_free_page(GFP_KERNEL); + if (!buf) { + kfree(item); + dlm_put(dlm); + return -ENOMEM; + } + + /* queue up work for dlm_request_all_locks_worker */ + dlm_grab(dlm); /* get an extra ref for the work item */ + dlm_init_work_item(dlm, item, dlm_request_all_locks_worker, buf); + item->u.ral.reco_master = lr->node_idx; + item->u.ral.dead_node = lr->dead_node; + spin_lock(&dlm->work_lock); + list_add_tail(&item->list, &dlm->work_list); + spin_unlock(&dlm->work_lock); + schedule_work(&dlm->dispatched_work); + + dlm_put(dlm); + return 0; +} + +static void dlm_request_all_locks_worker(struct dlm_work_item *item, void *data) +{ + struct dlm_migratable_lockres *mres; + struct dlm_lock_resource *res; + struct dlm_ctxt *dlm; + LIST_HEAD(resources); + struct list_head *iter; + int ret; + u8 dead_node, reco_master; + + dlm = item->dlm; + dead_node = item->u.ral.dead_node; + reco_master = item->u.ral.reco_master; + BUG_ON(dead_node != dlm->reco.dead_node); + BUG_ON(reco_master != dlm->reco.new_master); + + mres = (struct dlm_migratable_lockres *)data; + + /* lock resources should have already been moved to the + * dlm->reco.resources list. now move items from that list + * to a temp list if the dead owner matches. note that the + * whole cluster recovers only one node at a time, so we + * can safely move UNKNOWN lock resources for each recovery + * session. */ + dlm_move_reco_locks_to_list(dlm, &resources, dead_node); + + /* now we can begin blasting lockreses without the dlm lock */ + list_for_each(iter, &resources) { + res = list_entry (iter, struct dlm_lock_resource, recovering); + ret = dlm_send_one_lockres(dlm, res, mres, reco_master, + DLM_MRES_RECOVERY); + if (ret < 0) + mlog_errno(ret); + } + + /* move the resources back to the list */ + spin_lock(&dlm->spinlock); + list_splice_init(&resources, &dlm->reco.resources); + spin_unlock(&dlm->spinlock); + + ret = dlm_send_all_done_msg(dlm, dead_node, reco_master); + if (ret < 0) + mlog_errno(ret); + + free_page((unsigned long)data); +} + + +static int dlm_send_all_done_msg(struct dlm_ctxt *dlm, u8 dead_node, u8 send_to) +{ + int ret, tmpret; + struct dlm_reco_data_done done_msg; + + memset(&done_msg, 0, sizeof(done_msg)); + done_msg.node_idx = dlm->node_num; + done_msg.dead_node = dead_node; + mlog(0, "sending DATA DONE message to %u, " + "my node=%u, dead node=%u\n", send_to, done_msg.node_idx, + done_msg.dead_node); + + ret = o2net_send_message(DLM_RECO_DATA_DONE_MSG, dlm->key, &done_msg, + sizeof(done_msg), send_to, &tmpret); + /* negative status is ignored by the caller */ + if (ret >= 0) + ret = tmpret; + return ret; +} + + +int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_reco_data_done *done = (struct dlm_reco_data_done *)msg->buf; + struct list_head *iter; + struct dlm_reco_node_data *ndata = NULL; + int ret = -EINVAL; + + if (!dlm_grab(dlm)) + return -EINVAL; + + mlog(0, "got DATA DONE: dead_node=%u, reco.dead_node=%u, " + "node_idx=%u, this node=%u\n", done->dead_node, + dlm->reco.dead_node, done->node_idx, dlm->node_num); + BUG_ON(done->dead_node != dlm->reco.dead_node); + + spin_lock(&dlm_reco_state_lock); + list_for_each(iter, &dlm->reco.node_data) { + ndata = list_entry (iter, struct dlm_reco_node_data, list); + if (ndata->node_num != done->node_idx) + continue; + + switch (ndata->state) { + case DLM_RECO_NODE_DATA_INIT: + case DLM_RECO_NODE_DATA_DEAD: + case DLM_RECO_NODE_DATA_DONE: + case DLM_RECO_NODE_DATA_FINALIZE_SENT: + mlog(ML_ERROR, "bad ndata state for node %u:" + " state=%d\n", ndata->node_num, + ndata->state); + BUG(); + break; + case DLM_RECO_NODE_DATA_RECEIVING: + case DLM_RECO_NODE_DATA_REQUESTED: + case DLM_RECO_NODE_DATA_REQUESTING: + mlog(0, "node %u is DONE sending " + "recovery data!\n", + ndata->node_num); + + ndata->state = DLM_RECO_NODE_DATA_DONE; + ret = 0; + break; + } + } + spin_unlock(&dlm_reco_state_lock); + + /* wake the recovery thread, some node is done */ + if (!ret) + dlm_kick_recovery_thread(dlm); + + if (ret < 0) + mlog(ML_ERROR, "failed to find recovery node data for node " + "%u\n", done->node_idx); + dlm_put(dlm); + + mlog(0, "leaving reco data done handler, ret=%d\n", ret); + return ret; +} + +static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm, + struct list_head *list, + u8 dead_node) +{ + struct dlm_lock_resource *res; + struct list_head *iter, *iter2; + + spin_lock(&dlm->spinlock); + list_for_each_safe(iter, iter2, &dlm->reco.resources) { + res = list_entry (iter, struct dlm_lock_resource, recovering); + if (dlm_is_recovery_lock(res->lockname.name, + res->lockname.len)) + continue; + if (res->owner == dead_node) { + mlog(0, "found lockres owned by dead node while " + "doing recovery for node %u. sending it.\n", + dead_node); + list_del_init(&res->recovering); + list_add_tail(&res->recovering, list); + } else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) { + mlog(0, "found UNKNOWN owner while doing recovery " + "for node %u. sending it.\n", dead_node); + list_del_init(&res->recovering); + list_add_tail(&res->recovering, list); + } + } + spin_unlock(&dlm->spinlock); +} + +static inline int dlm_num_locks_in_lockres(struct dlm_lock_resource *res) +{ + int total_locks = 0; + struct list_head *iter, *queue = &res->granted; + int i; + + for (i=0; i<3; i++) { + list_for_each(iter, queue) + total_locks++; + queue++; + } + return total_locks; +} + + +static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm, + struct dlm_migratable_lockres *mres, + u8 send_to, + struct dlm_lock_resource *res, + int total_locks) +{ + u64 mig_cookie = be64_to_cpu(mres->mig_cookie); + int mres_total_locks = be32_to_cpu(mres->total_locks); + int sz, ret = 0, status = 0; + u8 orig_flags = mres->flags, + orig_master = mres->master; + + BUG_ON(mres->num_locks > DLM_MAX_MIGRATABLE_LOCKS); + if (!mres->num_locks) + return 0; + + sz = sizeof(struct dlm_migratable_lockres) + + (mres->num_locks * sizeof(struct dlm_migratable_lock)); + + /* add an all-done flag if we reached the last lock */ + orig_flags = mres->flags; + BUG_ON(total_locks > mres_total_locks); + if (total_locks == mres_total_locks) + mres->flags |= DLM_MRES_ALL_DONE; + + /* send it */ + ret = o2net_send_message(DLM_MIG_LOCKRES_MSG, dlm->key, mres, + sz, send_to, &status); + if (ret < 0) { + /* XXX: negative status is not handled. + * this will end up killing this node. */ + mlog_errno(ret); + } else { + /* might get an -ENOMEM back here */ + ret = status; + if (ret < 0) { + mlog_errno(ret); + + if (ret == -EFAULT) { + mlog(ML_ERROR, "node %u told me to kill " + "myself!\n", send_to); + BUG(); + } + } + } + + /* zero and reinit the message buffer */ + dlm_init_migratable_lockres(mres, res->lockname.name, + res->lockname.len, mres_total_locks, + mig_cookie, orig_flags, orig_master); + return ret; +} + +static void dlm_init_migratable_lockres(struct dlm_migratable_lockres *mres, + const char *lockname, int namelen, + int total_locks, u64 cookie, + u8 flags, u8 master) +{ + /* mres here is one full page */ + memset(mres, 0, PAGE_SIZE); + mres->lockname_len = namelen; + memcpy(mres->lockname, lockname, namelen); + mres->num_locks = 0; + mres->total_locks = cpu_to_be32(total_locks); + mres->mig_cookie = cpu_to_be64(cookie); + mres->flags = flags; + mres->master = master; +} + + +/* returns 1 if this lock fills the network structure, + * 0 otherwise */ +static int dlm_add_lock_to_array(struct dlm_lock *lock, + struct dlm_migratable_lockres *mres, int queue) +{ + struct dlm_migratable_lock *ml; + int lock_num = mres->num_locks; + + ml = &(mres->ml[lock_num]); + ml->cookie = lock->ml.cookie; + ml->type = lock->ml.type; + ml->convert_type = lock->ml.convert_type; + ml->highest_blocked = lock->ml.highest_blocked; + ml->list = queue; + if (lock->lksb) { + ml->flags = lock->lksb->flags; + /* send our current lvb */ + if (ml->type == LKM_EXMODE || + ml->type == LKM_PRMODE) { + /* if it is already set, this had better be a PR + * and it has to match */ + if (mres->lvb[0] && (ml->type == LKM_EXMODE || + memcmp(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN))) { + mlog(ML_ERROR, "mismatched lvbs!\n"); + __dlm_print_one_lock_resource(lock->lockres); + BUG(); + } + memcpy(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN); + } + } + ml->node = lock->ml.node; + mres->num_locks++; + /* we reached the max, send this network message */ + if (mres->num_locks == DLM_MAX_MIGRATABLE_LOCKS) + return 1; + return 0; +} + + +int dlm_send_one_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_migratable_lockres *mres, + u8 send_to, u8 flags) +{ + struct list_head *queue, *iter; + int total_locks, i; + u64 mig_cookie = 0; + struct dlm_lock *lock; + int ret = 0; + + BUG_ON(!(flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION))); + + mlog(0, "sending to %u\n", send_to); + + total_locks = dlm_num_locks_in_lockres(res); + if (total_locks > DLM_MAX_MIGRATABLE_LOCKS) { + /* rare, but possible */ + mlog(0, "argh. lockres has %d locks. this will " + "require more than one network packet to " + "migrate\n", total_locks); + mig_cookie = dlm_get_next_mig_cookie(); + } + + dlm_init_migratable_lockres(mres, res->lockname.name, + res->lockname.len, total_locks, + mig_cookie, flags, res->owner); + + total_locks = 0; + for (i=DLM_GRANTED_LIST; i<=DLM_BLOCKED_LIST; i++) { + queue = dlm_list_idx_to_ptr(res, i); + list_for_each(iter, queue) { + lock = list_entry (iter, struct dlm_lock, list); + + /* add another lock. */ + total_locks++; + if (!dlm_add_lock_to_array(lock, mres, i)) + continue; + + /* this filled the lock message, + * we must send it immediately. */ + ret = dlm_send_mig_lockres_msg(dlm, mres, send_to, + res, total_locks); + if (ret < 0) { + // TODO + mlog(ML_ERROR, "dlm_send_mig_lockres_msg " + "returned %d, TODO\n", ret); + BUG(); + } + } + } + /* flush any remaining locks */ + ret = dlm_send_mig_lockres_msg(dlm, mres, send_to, res, total_locks); + if (ret < 0) { + // TODO + mlog(ML_ERROR, "dlm_send_mig_lockres_msg returned %d, " + "TODO\n", ret); + BUG(); + } + return ret; +} + + + +/* + * this message will contain no more than one page worth of + * recovery data, and it will work on only one lockres. + * there may be many locks in this page, and we may need to wait + * for additional packets to complete all the locks (rare, but + * possible). + */ +/* + * NOTE: the allocation error cases here are scary + * we really cannot afford to fail an alloc in recovery + * do we spin? returning an error only delays the problem really + */ + +int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_migratable_lockres *mres = + (struct dlm_migratable_lockres *)msg->buf; + int ret = 0; + u8 real_master; + char *buf = NULL; + struct dlm_work_item *item = NULL; + struct dlm_lock_resource *res = NULL; + + if (!dlm_grab(dlm)) + return -EINVAL; + + BUG_ON(!(mres->flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION))); + + real_master = mres->master; + if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) { + /* cannot migrate a lockres with no master */ + BUG_ON(!(mres->flags & DLM_MRES_RECOVERY)); + } + + mlog(0, "%s message received from node %u\n", + (mres->flags & DLM_MRES_RECOVERY) ? + "recovery" : "migration", mres->master); + if (mres->flags & DLM_MRES_ALL_DONE) + mlog(0, "all done flag. all lockres data received!\n"); + + ret = -ENOMEM; + buf = kmalloc(be16_to_cpu(msg->data_len), GFP_KERNEL); + item = kcalloc(1, sizeof(*item), GFP_KERNEL); + if (!buf || !item) + goto leave; + + /* lookup the lock to see if we have a secondary queue for this + * already... just add the locks in and this will have its owner + * and RECOVERY flag changed when it completes. */ + res = dlm_lookup_lockres(dlm, mres->lockname, mres->lockname_len); + if (res) { + /* this will get a ref on res */ + /* mark it as recovering/migrating and hash it */ + spin_lock(&res->spinlock); + if (mres->flags & DLM_MRES_RECOVERY) { + res->state |= DLM_LOCK_RES_RECOVERING; + } else { + if (res->state & DLM_LOCK_RES_MIGRATING) { + /* this is at least the second + * lockres message */ + mlog(0, "lock %.*s is already migrating\n", + mres->lockname_len, + mres->lockname); + } else if (res->state & DLM_LOCK_RES_RECOVERING) { + /* caller should BUG */ + mlog(ML_ERROR, "node is attempting to migrate " + "lock %.*s, but marked as recovering!\n", + mres->lockname_len, mres->lockname); + ret = -EFAULT; + spin_unlock(&res->spinlock); + goto leave; + } + res->state |= DLM_LOCK_RES_MIGRATING; + } + spin_unlock(&res->spinlock); + } else { + /* need to allocate, just like if it was + * mastered here normally */ + res = dlm_new_lockres(dlm, mres->lockname, mres->lockname_len); + if (!res) + goto leave; + + /* to match the ref that we would have gotten if + * dlm_lookup_lockres had succeeded */ + dlm_lockres_get(res); + + /* mark it as recovering/migrating and hash it */ + if (mres->flags & DLM_MRES_RECOVERY) + res->state |= DLM_LOCK_RES_RECOVERING; + else + res->state |= DLM_LOCK_RES_MIGRATING; + + spin_lock(&dlm->spinlock); + __dlm_insert_lockres(dlm, res); + spin_unlock(&dlm->spinlock); + + /* now that the new lockres is inserted, + * make it usable by other processes */ + spin_lock(&res->spinlock); + res->state &= ~DLM_LOCK_RES_IN_PROGRESS; + spin_unlock(&res->spinlock); + + /* add an extra ref for just-allocated lockres + * otherwise the lockres will be purged immediately */ + dlm_lockres_get(res); + + } + + /* at this point we have allocated everything we need, + * and we have a hashed lockres with an extra ref and + * the proper res->state flags. */ + ret = 0; + if (mres->master == DLM_LOCK_RES_OWNER_UNKNOWN) { + /* migration cannot have an unknown master */ + BUG_ON(!(mres->flags & DLM_MRES_RECOVERY)); + mlog(0, "recovery has passed me a lockres with an " + "unknown owner.. will need to requery: " + "%.*s\n", mres->lockname_len, mres->lockname); + } else { + spin_lock(&res->spinlock); + dlm_change_lockres_owner(dlm, res, dlm->node_num); + spin_unlock(&res->spinlock); + } + + /* queue up work for dlm_mig_lockres_worker */ + dlm_grab(dlm); /* get an extra ref for the work item */ + memcpy(buf, msg->buf, be16_to_cpu(msg->data_len)); /* copy the whole message */ + dlm_init_work_item(dlm, item, dlm_mig_lockres_worker, buf); + item->u.ml.lockres = res; /* already have a ref */ + item->u.ml.real_master = real_master; + spin_lock(&dlm->work_lock); + list_add_tail(&item->list, &dlm->work_list); + spin_unlock(&dlm->work_lock); + schedule_work(&dlm->dispatched_work); + +leave: + dlm_put(dlm); + if (ret < 0) { + if (buf) + kfree(buf); + if (item) + kfree(item); + } + + mlog_exit(ret); + return ret; +} + + +static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_migratable_lockres *mres; + int ret = 0; + struct dlm_lock_resource *res; + u8 real_master; + + dlm = item->dlm; + mres = (struct dlm_migratable_lockres *)data; + + res = item->u.ml.lockres; + real_master = item->u.ml.real_master; + + if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) { + /* this case is super-rare. only occurs if + * node death happens during migration. */ +again: + ret = dlm_lockres_master_requery(dlm, res, &real_master); + if (ret < 0) { + mlog(0, "dlm_lockres_master_requery failure: %d\n", + ret); + goto again; + } + if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) { + mlog(0, "lockres %.*s not claimed. " + "this node will take it.\n", + res->lockname.len, res->lockname.name); + } else { + mlog(0, "master needs to respond to sender " + "that node %u still owns %.*s\n", + real_master, res->lockname.len, + res->lockname.name); + /* cannot touch this lockres */ + goto leave; + } + } + + ret = dlm_process_recovery_data(dlm, res, mres); + if (ret < 0) + mlog(0, "dlm_process_recovery_data returned %d\n", ret); + else + mlog(0, "dlm_process_recovery_data succeeded\n"); + + if ((mres->flags & (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) == + (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) { + ret = dlm_finish_migration(dlm, res, mres->master); + if (ret < 0) + mlog_errno(ret); + } + +leave: + kfree(data); + mlog_exit(ret); +} + + + +static int dlm_lockres_master_requery(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 *real_master) +{ + struct dlm_node_iter iter; + int nodenum; + int ret = 0; + + *real_master = DLM_LOCK_RES_OWNER_UNKNOWN; + + /* we only reach here if one of the two nodes in a + * migration died while the migration was in progress. + * at this point we need to requery the master. we + * know that the new_master got as far as creating + * an mle on at least one node, but we do not know + * if any nodes had actually cleared the mle and set + * the master to the new_master. the old master + * is supposed to set the owner to UNKNOWN in the + * event of a new_master death, so the only possible + * responses that we can get from nodes here are + * that the master is new_master, or that the master + * is UNKNOWN. + * if all nodes come back with UNKNOWN then we know + * the lock needs remastering here. + * if any node comes back with a valid master, check + * to see if that master is the one that we are + * recovering. if so, then the new_master died and + * we need to remaster this lock. if not, then the + * new_master survived and that node will respond to + * other nodes about the owner. + * if there is an owner, this node needs to dump this + * lockres and alert the sender that this lockres + * was rejected. */ + spin_lock(&dlm->spinlock); + dlm_node_iter_init(dlm->domain_map, &iter); + spin_unlock(&dlm->spinlock); + + while ((nodenum = dlm_node_iter_next(&iter)) >= 0) { + /* do not send to self */ + if (nodenum == dlm->node_num) + continue; + ret = dlm_do_master_requery(dlm, res, nodenum, real_master); + if (ret < 0) { + mlog_errno(ret); + BUG(); + /* TODO: need to figure a way to restart this */ + } + if (*real_master != DLM_LOCK_RES_OWNER_UNKNOWN) { + mlog(0, "lock master is %u\n", *real_master); + break; + } + } + return ret; +} + + +static int dlm_do_master_requery(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 nodenum, u8 *real_master) +{ + int ret = -EINVAL; + struct dlm_master_requery req; + int status = DLM_LOCK_RES_OWNER_UNKNOWN; + + memset(&req, 0, sizeof(req)); + req.node_idx = dlm->node_num; + req.namelen = res->lockname.len; + memcpy(req.name, res->lockname.name, res->lockname.len); + + ret = o2net_send_message(DLM_MASTER_REQUERY_MSG, dlm->key, + &req, sizeof(req), nodenum, &status); + /* XXX: negative status not handled properly here. */ + if (ret < 0) + mlog_errno(ret); + else { + BUG_ON(status < 0); + BUG_ON(status > DLM_LOCK_RES_OWNER_UNKNOWN); + *real_master = (u8) (status & 0xff); + mlog(0, "node %u responded to master requery with %u\n", + nodenum, *real_master); + ret = 0; + } + return ret; +} + + +/* this function cannot error, so unless the sending + * or receiving of the message failed, the owner can + * be trusted */ +int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_master_requery *req = (struct dlm_master_requery *)msg->buf; + struct dlm_lock_resource *res = NULL; + int master = DLM_LOCK_RES_OWNER_UNKNOWN; + u32 flags = DLM_ASSERT_MASTER_REQUERY; + + if (!dlm_grab(dlm)) { + /* since the domain has gone away on this + * node, the proper response is UNKNOWN */ + return master; + } + + spin_lock(&dlm->spinlock); + res = __dlm_lookup_lockres(dlm, req->name, req->namelen); + if (res) { + spin_lock(&res->spinlock); + master = res->owner; + if (master == dlm->node_num) { + int ret = dlm_dispatch_assert_master(dlm, res, + 0, 0, flags); + if (ret < 0) { + mlog_errno(-ENOMEM); + /* retry!? */ + BUG(); + } + } + spin_unlock(&res->spinlock); + } + spin_unlock(&dlm->spinlock); + + dlm_put(dlm); + return master; +} + +static inline struct list_head * +dlm_list_num_to_pointer(struct dlm_lock_resource *res, int list_num) +{ + struct list_head *ret; + BUG_ON(list_num < 0); + BUG_ON(list_num > 2); + ret = &(res->granted); + ret += list_num; + return ret; +} +/* TODO: do ast flush business + * TODO: do MIGRATING and RECOVERING spinning + */ + +/* +* NOTE about in-flight requests during migration: +* +* Before attempting the migrate, the master has marked the lockres as +* MIGRATING and then flushed all of its pending ASTS. So any in-flight +* requests either got queued before the MIGRATING flag got set, in which +* case the lock data will reflect the change and a return message is on +* the way, or the request failed to get in before MIGRATING got set. In +* this case, the caller will be told to spin and wait for the MIGRATING +* flag to be dropped, then recheck the master. +* This holds true for the convert, cancel and unlock cases, and since lvb +* updates are tied to these same messages, it applies to lvb updates as +* well. For the lock case, there is no way a lock can be on the master +* queue and not be on the secondary queue since the lock is always added +* locally first. This means that the new target node will never be sent +* a lock that he doesn't already have on the list. +* In total, this means that the local lock is correct and should not be +* updated to match the one sent by the master. Any messages sent back +* from the master before the MIGRATING flag will bring the lock properly +* up-to-date, and the change will be ordered properly for the waiter. +* We will *not* attempt to modify the lock underneath the waiter. +*/ + +static int dlm_process_recovery_data(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_migratable_lockres *mres) +{ + struct dlm_migratable_lock *ml; + struct list_head *queue; + struct dlm_lock *newlock = NULL; + struct dlm_lockstatus *lksb = NULL; + int ret = 0; + int i; + struct list_head *iter; + struct dlm_lock *lock = NULL; + + mlog(0, "running %d locks for this lockres\n", mres->num_locks); + for (i=0; i<mres->num_locks; i++) { + ml = &(mres->ml[i]); + BUG_ON(ml->highest_blocked != LKM_IVMODE); + newlock = NULL; + lksb = NULL; + + queue = dlm_list_num_to_pointer(res, ml->list); + + /* if the lock is for the local node it needs to + * be moved to the proper location within the queue. + * do not allocate a new lock structure. */ + if (ml->node == dlm->node_num) { + /* MIGRATION ONLY! */ + BUG_ON(!(mres->flags & DLM_MRES_MIGRATION)); + + spin_lock(&res->spinlock); + list_for_each(iter, queue) { + lock = list_entry (iter, struct dlm_lock, list); + if (lock->ml.cookie != ml->cookie) + lock = NULL; + else + break; + } + + /* lock is always created locally first, and + * destroyed locally last. it must be on the list */ + if (!lock) { + mlog(ML_ERROR, "could not find local lock " + "with cookie %"MLFu64"!\n", + ml->cookie); + BUG(); + } + BUG_ON(lock->ml.node != ml->node); + + /* see NOTE above about why we do not update + * to match the master here */ + + /* move the lock to its proper place */ + /* do not alter lock refcount. switching lists. */ + list_del_init(&lock->list); + list_add_tail(&lock->list, queue); + spin_unlock(&res->spinlock); + + mlog(0, "just reordered a local lock!\n"); + continue; + } + + /* lock is for another node. */ + newlock = dlm_new_lock(ml->type, ml->node, + be64_to_cpu(ml->cookie), NULL); + if (!newlock) { + ret = -ENOMEM; + goto leave; + } + lksb = newlock->lksb; + dlm_lock_attach_lockres(newlock, res); + + if (ml->convert_type != LKM_IVMODE) { + BUG_ON(queue != &res->converting); + newlock->ml.convert_type = ml->convert_type; + } + lksb->flags |= (ml->flags & + (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB)); + + if (mres->lvb[0]) { + if (lksb->flags & DLM_LKSB_PUT_LVB) { + /* other node was trying to update + * lvb when node died. recreate the + * lksb with the updated lvb. */ + memcpy(lksb->lvb, mres->lvb, DLM_LVB_LEN); + } else { + /* otherwise, the node is sending its + * most recent valid lvb info */ + BUG_ON(ml->type != LKM_EXMODE && + ml->type != LKM_PRMODE); + if (res->lvb[0] && (ml->type == LKM_EXMODE || + memcmp(res->lvb, mres->lvb, DLM_LVB_LEN))) { + mlog(ML_ERROR, "received bad lvb!\n"); + __dlm_print_one_lock_resource(res); + BUG(); + } + memcpy(res->lvb, mres->lvb, DLM_LVB_LEN); + } + } + + + /* NOTE: + * wrt lock queue ordering and recovery: + * 1. order of locks on granted queue is + * meaningless. + * 2. order of locks on converting queue is + * LOST with the node death. sorry charlie. + * 3. order of locks on the blocked queue is + * also LOST. + * order of locks does not affect integrity, it + * just means that a lock request may get pushed + * back in line as a result of the node death. + * also note that for a given node the lock order + * for its secondary queue locks is preserved + * relative to each other, but clearly *not* + * preserved relative to locks from other nodes. + */ + spin_lock(&res->spinlock); + dlm_lock_get(newlock); + list_add_tail(&newlock->list, queue); + spin_unlock(&res->spinlock); + } + mlog(0, "done running all the locks\n"); + +leave: + if (ret < 0) { + mlog_errno(ret); + if (newlock) + dlm_lock_put(newlock); + } + + mlog_exit(ret); + return ret; +} + +void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res) +{ + int i; + struct list_head *queue, *iter, *iter2; + struct dlm_lock *lock; + + res->state |= DLM_LOCK_RES_RECOVERING; + if (!list_empty(&res->recovering)) + list_del_init(&res->recovering); + list_add_tail(&res->recovering, &dlm->reco.resources); + + /* find any pending locks and put them back on proper list */ + for (i=DLM_BLOCKED_LIST; i>=DLM_GRANTED_LIST; i--) { + queue = dlm_list_idx_to_ptr(res, i); + list_for_each_safe(iter, iter2, queue) { + lock = list_entry (iter, struct dlm_lock, list); + dlm_lock_get(lock); + if (lock->convert_pending) { + /* move converting lock back to granted */ + BUG_ON(i != DLM_CONVERTING_LIST); + mlog(0, "node died with convert pending " + "on %.*s. move back to granted list.\n", + res->lockname.len, res->lockname.name); + dlm_revert_pending_convert(res, lock); + lock->convert_pending = 0; + } else if (lock->lock_pending) { + /* remove pending lock requests completely */ + BUG_ON(i != DLM_BLOCKED_LIST); + mlog(0, "node died with lock pending " + "on %.*s. remove from blocked list and skip.\n", + res->lockname.len, res->lockname.name); + /* lock will be floating until ref in + * dlmlock_remote is freed after the network + * call returns. ok for it to not be on any + * list since no ast can be called + * (the master is dead). */ + dlm_revert_pending_lock(res, lock); + lock->lock_pending = 0; + } else if (lock->unlock_pending) { + /* if an unlock was in progress, treat as + * if this had completed successfully + * before sending this lock state to the + * new master. note that the dlm_unlock + * call is still responsible for calling + * the unlockast. that will happen after + * the network call times out. for now, + * just move lists to prepare the new + * recovery master. */ + BUG_ON(i != DLM_GRANTED_LIST); + mlog(0, "node died with unlock pending " + "on %.*s. remove from blocked list and skip.\n", + res->lockname.len, res->lockname.name); + dlm_commit_pending_unlock(res, lock); + lock->unlock_pending = 0; + } else if (lock->cancel_pending) { + /* if a cancel was in progress, treat as + * if this had completed successfully + * before sending this lock state to the + * new master */ + BUG_ON(i != DLM_CONVERTING_LIST); + mlog(0, "node died with cancel pending " + "on %.*s. move back to granted list.\n", + res->lockname.len, res->lockname.name); + dlm_commit_pending_cancel(res, lock); + lock->cancel_pending = 0; + } + dlm_lock_put(lock); + } + } +} + + + +/* removes all recovered locks from the recovery list. + * sets the res->owner to the new master. + * unsets the RECOVERY flag and wakes waiters. */ +static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm, + u8 dead_node, u8 new_master) +{ + int i; + struct list_head *iter, *iter2, *bucket; + struct dlm_lock_resource *res; + + mlog_entry_void(); + + assert_spin_locked(&dlm->spinlock); + + list_for_each_safe(iter, iter2, &dlm->reco.resources) { + res = list_entry (iter, struct dlm_lock_resource, recovering); + if (res->owner == dead_node) { + list_del_init(&res->recovering); + spin_lock(&res->spinlock); + dlm_change_lockres_owner(dlm, res, new_master); + res->state &= ~DLM_LOCK_RES_RECOVERING; + __dlm_dirty_lockres(dlm, res); + spin_unlock(&res->spinlock); + wake_up(&res->wq); + } + } + + /* this will become unnecessary eventually, but + * for now we need to run the whole hash, clear + * the RECOVERING state and set the owner + * if necessary */ + for (i=0; i<DLM_HASH_SIZE; i++) { + bucket = &(dlm->resources[i]); + list_for_each(iter, bucket) { + res = list_entry (iter, struct dlm_lock_resource, list); + if (res->state & DLM_LOCK_RES_RECOVERING) { + if (res->owner == dead_node) { + mlog(0, "(this=%u) res %.*s owner=%u " + "was not on recovering list, but " + "clearing state anyway\n", + dlm->node_num, res->lockname.len, + res->lockname.name, new_master); + } else if (res->owner == dlm->node_num) { + mlog(0, "(this=%u) res %.*s owner=%u " + "was not on recovering list, " + "owner is THIS node, clearing\n", + dlm->node_num, res->lockname.len, + res->lockname.name, new_master); + } else + continue; + + spin_lock(&res->spinlock); + dlm_change_lockres_owner(dlm, res, new_master); + res->state &= ~DLM_LOCK_RES_RECOVERING; + __dlm_dirty_lockres(dlm, res); + spin_unlock(&res->spinlock); + wake_up(&res->wq); + } + } + } +} + +static inline int dlm_lvb_needs_invalidation(struct dlm_lock *lock, int local) +{ + if (local) { + if (lock->ml.type != LKM_EXMODE && + lock->ml.type != LKM_PRMODE) + return 1; + } else if (lock->ml.type == LKM_EXMODE) + return 1; + return 0; +} + +static void dlm_revalidate_lvb(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, u8 dead_node) +{ + struct list_head *iter, *queue; + struct dlm_lock *lock; + int blank_lvb = 0, local = 0; + int i; + u8 search_node; + + assert_spin_locked(&dlm->spinlock); + assert_spin_locked(&res->spinlock); + + if (res->owner == dlm->node_num) + /* if this node owned the lockres, and if the dead node + * had an EX when he died, blank out the lvb */ + search_node = dead_node; + else { + /* if this is a secondary lockres, and we had no EX or PR + * locks granted, we can no longer trust the lvb */ + search_node = dlm->node_num; + local = 1; /* check local state for valid lvb */ + } + + for (i=DLM_GRANTED_LIST; i<=DLM_CONVERTING_LIST; i++) { + queue = dlm_list_idx_to_ptr(res, i); + list_for_each(iter, queue) { + lock = list_entry (iter, struct dlm_lock, list); + if (lock->ml.node == search_node) { + if (dlm_lvb_needs_invalidation(lock, local)) { + /* zero the lksb lvb and lockres lvb */ + blank_lvb = 1; + memset(lock->lksb->lvb, 0, DLM_LVB_LEN); + } + } + } + } + + if (blank_lvb) { + mlog(0, "clearing %.*s lvb, dead node %u had EX\n", + res->lockname.len, res->lockname.name, dead_node); + memset(res->lvb, 0, DLM_LVB_LEN); + } +} + +static void dlm_free_dead_locks(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, u8 dead_node) +{ + struct list_head *iter, *tmpiter; + struct dlm_lock *lock; + + /* this node is the lockres master: + * 1) remove any stale locks for the dead node + * 2) if the dead node had an EX when he died, blank out the lvb + */ + assert_spin_locked(&dlm->spinlock); + assert_spin_locked(&res->spinlock); + + /* TODO: check pending_asts, pending_basts here */ + list_for_each_safe(iter, tmpiter, &res->granted) { + lock = list_entry (iter, struct dlm_lock, list); + if (lock->ml.node == dead_node) { + list_del_init(&lock->list); + dlm_lock_put(lock); + } + } + list_for_each_safe(iter, tmpiter, &res->converting) { + lock = list_entry (iter, struct dlm_lock, list); + if (lock->ml.node == dead_node) { + list_del_init(&lock->list); + dlm_lock_put(lock); + } + } + list_for_each_safe(iter, tmpiter, &res->blocked) { + lock = list_entry (iter, struct dlm_lock, list); + if (lock->ml.node == dead_node) { + list_del_init(&lock->list); + dlm_lock_put(lock); + } + } + + /* do not kick thread yet */ + __dlm_dirty_lockres(dlm, res); +} + +/* if this node is the recovery master, and there are no + * locks for a given lockres owned by this node that are in + * either PR or EX mode, zero out the lvb before requesting. + * + */ + + +static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node) +{ + struct list_head *iter; + struct dlm_lock_resource *res; + int i; + struct list_head *bucket; + + + /* purge any stale mles */ + dlm_clean_master_list(dlm, dead_node); + + /* + * now clean up all lock resources. there are two rules: + * + * 1) if the dead node was the master, move the lockres + * to the recovering list. set the RECOVERING flag. + * this lockres needs to be cleaned up before it can + * be used further. + * + * 2) if this node was the master, remove all locks from + * each of the lockres queues that were owned by the + * dead node. once recovery finishes, the dlm thread + * can be kicked again to see if any ASTs or BASTs + * need to be fired as a result. + */ + for (i=0; i<DLM_HASH_SIZE; i++) { + bucket = &(dlm->resources[i]); + list_for_each(iter, bucket) { + res = list_entry (iter, struct dlm_lock_resource, list); + if (dlm_is_recovery_lock(res->lockname.name, + res->lockname.len)) + continue; + + spin_lock(&res->spinlock); + /* zero the lvb if necessary */ + dlm_revalidate_lvb(dlm, res, dead_node); + if (res->owner == dead_node) + dlm_move_lockres_to_recovery_list(dlm, res); + else if (res->owner == dlm->node_num) { + dlm_free_dead_locks(dlm, res, dead_node); + __dlm_lockres_calc_usage(dlm, res); + } + spin_unlock(&res->spinlock); + } + } + +} + +static void __dlm_hb_node_down(struct dlm_ctxt *dlm, int idx) +{ + assert_spin_locked(&dlm->spinlock); + + /* check to see if the node is already considered dead */ + if (!test_bit(idx, dlm->live_nodes_map)) { + mlog(0, "for domain %s, node %d is already dead. " + "another node likely did recovery already.\n", + dlm->name, idx); + return; + } + + /* check to see if we do not care about this node */ + if (!test_bit(idx, dlm->domain_map)) { + /* This also catches the case that we get a node down + * but haven't joined the domain yet. */ + mlog(0, "node %u already removed from domain!\n", idx); + return; + } + + clear_bit(idx, dlm->live_nodes_map); + + /* Clean up join state on node death. */ + if (dlm->joining_node == idx) { + mlog(0, "Clearing join state for node %u\n", idx); + __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN); + } + + /* make sure local cleanup occurs before the heartbeat events */ + if (!test_bit(idx, dlm->recovery_map)) + dlm_do_local_recovery_cleanup(dlm, idx); + + /* notify anything attached to the heartbeat events */ + dlm_hb_event_notify_attached(dlm, idx, 0); + + mlog(0, "node %u being removed from domain map!\n", idx); + clear_bit(idx, dlm->domain_map); + /* wake up migration waiters if a node goes down. + * perhaps later we can genericize this for other waiters. */ + wake_up(&dlm->migration_wq); + + if (test_bit(idx, dlm->recovery_map)) + mlog(0, "domain %s, node %u already added " + "to recovery map!\n", dlm->name, idx); + else + set_bit(idx, dlm->recovery_map); +} + +void dlm_hb_node_down_cb(struct o2nm_node *node, int idx, void *data) +{ + struct dlm_ctxt *dlm = data; + + if (!dlm_grab(dlm)) + return; + + spin_lock(&dlm->spinlock); + __dlm_hb_node_down(dlm, idx); + spin_unlock(&dlm->spinlock); + + dlm_put(dlm); +} + +void dlm_hb_node_up_cb(struct o2nm_node *node, int idx, void *data) +{ + struct dlm_ctxt *dlm = data; + + if (!dlm_grab(dlm)) + return; + + spin_lock(&dlm->spinlock); + + set_bit(idx, dlm->live_nodes_map); + + /* notify any mles attached to the heartbeat events */ + dlm_hb_event_notify_attached(dlm, idx, 1); + + spin_unlock(&dlm->spinlock); + + dlm_put(dlm); +} + +static void dlm_reco_ast(void *astdata) +{ + struct dlm_ctxt *dlm = astdata; + mlog(0, "ast for recovery lock fired!, this=%u, dlm=%s\n", + dlm->node_num, dlm->name); +} +static void dlm_reco_bast(void *astdata, int blocked_type) +{ + struct dlm_ctxt *dlm = astdata; + mlog(0, "bast for recovery lock fired!, this=%u, dlm=%s\n", + dlm->node_num, dlm->name); +} +static void dlm_reco_unlock_ast(void *astdata, enum dlm_status st) +{ + mlog(0, "unlockast for recovery lock fired!\n"); +} + + +static int dlm_pick_recovery_master(struct dlm_ctxt *dlm) +{ + enum dlm_status ret; + struct dlm_lockstatus lksb; + int status = -EINVAL; + + mlog(0, "starting recovery of %s at %lu, dead=%u, this=%u\n", + dlm->name, jiffies, dlm->reco.dead_node, dlm->node_num); +retry: + memset(&lksb, 0, sizeof(lksb)); + + ret = dlmlock(dlm, LKM_EXMODE, &lksb, LKM_NOQUEUE|LKM_RECOVERY, + DLM_RECOVERY_LOCK_NAME, dlm_reco_ast, dlm, dlm_reco_bast); + + if (ret == DLM_NORMAL) { + mlog(0, "dlm=%s dlmlock says I got it (this=%u)\n", + dlm->name, dlm->node_num); + /* I am master, send message to all nodes saying + * that I am beginning a recovery session */ + status = dlm_send_begin_reco_message(dlm, + dlm->reco.dead_node); + + /* recovery lock is a special case. ast will not get fired, + * so just go ahead and unlock it. */ + ret = dlmunlock(dlm, &lksb, 0, dlm_reco_unlock_ast, dlm); + if (ret != DLM_NORMAL) { + /* this would really suck. this could only happen + * if there was a network error during the unlock + * because of node death. this means the unlock + * is actually "done" and the lock structure is + * even freed. we can continue, but only + * because this specific lock name is special. */ + mlog(0, "dlmunlock returned %d\n", ret); + } + + if (status < 0) { + mlog(0, "failed to send recovery message. " + "must retry with new node map.\n"); + goto retry; + } + } else if (ret == DLM_NOTQUEUED) { + mlog(0, "dlm=%s dlmlock says another node got it (this=%u)\n", + dlm->name, dlm->node_num); + /* another node is master. wait on + * reco.new_master != O2NM_INVALID_NODE_NUM */ + status = -EEXIST; + } + + return status; +} + +static int dlm_send_begin_reco_message(struct dlm_ctxt *dlm, u8 dead_node) +{ + struct dlm_begin_reco br; + int ret = 0; + struct dlm_node_iter iter; + int nodenum; + int status; + + mlog_entry("%u\n", dead_node); + + mlog(0, "dead node is %u\n", dead_node); + + spin_lock(&dlm->spinlock); + dlm_node_iter_init(dlm->domain_map, &iter); + spin_unlock(&dlm->spinlock); + + clear_bit(dead_node, iter.node_map); + + memset(&br, 0, sizeof(br)); + br.node_idx = dlm->node_num; + br.dead_node = dead_node; + + while ((nodenum = dlm_node_iter_next(&iter)) >= 0) { + ret = 0; + if (nodenum == dead_node) { + mlog(0, "not sending begin reco to dead node " + "%u\n", dead_node); + continue; + } + if (nodenum == dlm->node_num) { + mlog(0, "not sending begin reco to self\n"); + continue; + } + + ret = -EINVAL; + mlog(0, "attempting to send begin reco msg to %d\n", + nodenum); + ret = o2net_send_message(DLM_BEGIN_RECO_MSG, dlm->key, + &br, sizeof(br), nodenum, &status); + /* negative status is handled ok by caller here */ + if (ret >= 0) + ret = status; + if (ret < 0) { + struct dlm_lock_resource *res; + mlog_errno(ret); + mlog(ML_ERROR, "begin reco of dlm %s to node %u " + " returned %d\n", dlm->name, nodenum, ret); + res = dlm_lookup_lockres(dlm, DLM_RECOVERY_LOCK_NAME, + DLM_RECOVERY_LOCK_NAME_LEN); + if (res) { + dlm_print_one_lock_resource(res); + dlm_lockres_put(res); + } else { + mlog(ML_ERROR, "recovery lock not found\n"); + } + break; + } + } + + return ret; +} + +int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_begin_reco *br = (struct dlm_begin_reco *)msg->buf; + + /* ok to return 0, domain has gone away */ + if (!dlm_grab(dlm)) + return 0; + + mlog(0, "node %u wants to recover node %u\n", + br->node_idx, br->dead_node); + + dlm_fire_domain_eviction_callbacks(dlm, br->dead_node); + + spin_lock(&dlm->spinlock); + if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM) { + mlog(0, "new_master already set to %u!\n", + dlm->reco.new_master); + } + if (dlm->reco.dead_node != O2NM_INVALID_NODE_NUM) { + mlog(0, "dead_node already set to %u!\n", + dlm->reco.dead_node); + } + dlm->reco.new_master = br->node_idx; + dlm->reco.dead_node = br->dead_node; + if (!test_bit(br->dead_node, dlm->recovery_map)) { + mlog(ML_ERROR, "recovery master %u sees %u as dead, but this " + "node has not yet. marking %u as dead\n", + br->node_idx, br->dead_node, br->dead_node); + __dlm_hb_node_down(dlm, br->dead_node); + } + spin_unlock(&dlm->spinlock); + + dlm_kick_recovery_thread(dlm); + dlm_put(dlm); + return 0; +} + +static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm) +{ + int ret = 0; + struct dlm_finalize_reco fr; + struct dlm_node_iter iter; + int nodenum; + int status; + + mlog(0, "finishing recovery for node %s:%u\n", + dlm->name, dlm->reco.dead_node); + + spin_lock(&dlm->spinlock); + dlm_node_iter_init(dlm->domain_map, &iter); + spin_unlock(&dlm->spinlock); + + memset(&fr, 0, sizeof(fr)); + fr.node_idx = dlm->node_num; + fr.dead_node = dlm->reco.dead_node; + + while ((nodenum = dlm_node_iter_next(&iter)) >= 0) { + if (nodenum == dlm->node_num) + continue; + ret = o2net_send_message(DLM_FINALIZE_RECO_MSG, dlm->key, + &fr, sizeof(fr), nodenum, &status); + if (ret >= 0) { + ret = status; + if (dlm_is_host_down(ret)) { + /* this has no effect on this recovery + * session, so set the status to zero to + * finish out the last recovery */ + mlog(ML_ERROR, "node %u went down after this " + "node finished recovery.\n", nodenum); + ret = 0; + } + } + if (ret < 0) { + mlog_errno(ret); + break; + } + } + + return ret; +} + +int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_finalize_reco *fr = (struct dlm_finalize_reco *)msg->buf; + + /* ok to return 0, domain has gone away */ + if (!dlm_grab(dlm)) + return 0; + + mlog(0, "node %u finalizing recovery of node %u\n", + fr->node_idx, fr->dead_node); + + spin_lock(&dlm->spinlock); + + if (dlm->reco.new_master != fr->node_idx) { + mlog(ML_ERROR, "node %u sent recovery finalize msg, but node " + "%u is supposed to be the new master, dead=%u\n", + fr->node_idx, dlm->reco.new_master, fr->dead_node); + BUG(); + } + if (dlm->reco.dead_node != fr->dead_node) { + mlog(ML_ERROR, "node %u sent recovery finalize msg for dead " + "node %u, but node %u is supposed to be dead\n", + fr->node_idx, fr->dead_node, dlm->reco.dead_node); + BUG(); + } + + dlm_finish_local_lockres_recovery(dlm, fr->dead_node, fr->node_idx); + + spin_unlock(&dlm->spinlock); + + dlm_reset_recovery(dlm); + + dlm_kick_recovery_thread(dlm); + dlm_put(dlm); + return 0; +} diff --git a/fs/ocfs2/dlm/dlmthread.c b/fs/ocfs2/dlm/dlmthread.c new file mode 100644 index 0000000..92cd5cd --- /dev/null +++ b/fs/ocfs2/dlm/dlmthread.c @@ -0,0 +1,695 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmthread.c + * + * standalone DLM module + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + + +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/highmem.h> +#include <linux/utsname.h> +#include <linux/init.h> +#include <linux/sysctl.h> +#include <linux/random.h> +#include <linux/blkdev.h> +#include <linux/socket.h> +#include <linux/inet.h> +#include <linux/timer.h> +#include <linux/kthread.h> + + +#include "cluster/heartbeat.h" +#include "cluster/nodemanager.h" +#include "cluster/tcp.h" + +#include "dlmapi.h" +#include "dlmcommon.h" +#include "dlmdomain.h" + +#define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_THREAD) +#include "cluster/masklog.h" + +extern spinlock_t dlm_domain_lock; +extern struct list_head dlm_domains; + +static int dlm_thread(void *data); + +static void dlm_flush_asts(struct dlm_ctxt *dlm); + +#define dlm_lock_is_remote(dlm, lock) ((lock)->ml.node != (dlm)->node_num) + +/* will exit holding res->spinlock, but may drop in function */ +/* waits until flags are cleared on res->state */ +void __dlm_wait_on_lockres_flags(struct dlm_lock_resource *res, int flags) +{ + DECLARE_WAITQUEUE(wait, current); + + assert_spin_locked(&res->spinlock); + + add_wait_queue(&res->wq, &wait); +repeat: + set_current_state(TASK_UNINTERRUPTIBLE); + if (res->state & flags) { + spin_unlock(&res->spinlock); + schedule(); + spin_lock(&res->spinlock); + goto repeat; + } + remove_wait_queue(&res->wq, &wait); + current->state = TASK_RUNNING; +} + + +static int __dlm_lockres_unused(struct dlm_lock_resource *res) +{ + if (list_empty(&res->granted) && + list_empty(&res->converting) && + list_empty(&res->blocked) && + list_empty(&res->dirty)) + return 1; + return 0; +} + + +/* Call whenever you may have added or deleted something from one of + * the lockres queue's. This will figure out whether it belongs on the + * unused list or not and does the appropriate thing. */ +void __dlm_lockres_calc_usage(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res) +{ + mlog_entry("%.*s\n", res->lockname.len, res->lockname.name); + + assert_spin_locked(&dlm->spinlock); + assert_spin_locked(&res->spinlock); + + if (__dlm_lockres_unused(res)){ + if (list_empty(&res->purge)) { + mlog(0, "putting lockres %.*s from purge list\n", + res->lockname.len, res->lockname.name); + + res->last_used = jiffies; + list_add_tail(&res->purge, &dlm->purge_list); + dlm->purge_count++; + } + } else if (!list_empty(&res->purge)) { + mlog(0, "removing lockres %.*s from purge list\n", + res->lockname.len, res->lockname.name); + + list_del_init(&res->purge); + dlm->purge_count--; + } +} + +void dlm_lockres_calc_usage(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res) +{ + mlog_entry("%.*s\n", res->lockname.len, res->lockname.name); + spin_lock(&dlm->spinlock); + spin_lock(&res->spinlock); + + __dlm_lockres_calc_usage(dlm, res); + + spin_unlock(&res->spinlock); + spin_unlock(&dlm->spinlock); +} + +/* TODO: Eventual API: Called with the dlm spinlock held, may drop it + * to do migration, but will re-acquire before exit. */ +void dlm_purge_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *lockres) +{ + int master; + int ret; + + spin_lock(&lockres->spinlock); + master = lockres->owner == dlm->node_num; + spin_unlock(&lockres->spinlock); + + mlog(0, "purging lockres %.*s, master = %d\n", lockres->lockname.len, + lockres->lockname.name, master); + + /* Non master is the easy case -- no migration required, just + * quit. */ + if (!master) + goto finish; + + /* Wheee! Migrate lockres here! */ + spin_unlock(&dlm->spinlock); +again: + + ret = dlm_migrate_lockres(dlm, lockres, O2NM_MAX_NODES); + if (ret == -ENOTEMPTY) { + mlog(ML_ERROR, "lockres %.*s still has local locks!\n", + lockres->lockname.len, lockres->lockname.name); + + BUG(); + } else if (ret < 0) { + mlog(ML_NOTICE, "lockres %.*s: migrate failed, retrying\n", + lockres->lockname.len, lockres->lockname.name); + goto again; + } + + spin_lock(&dlm->spinlock); + +finish: + if (!list_empty(&lockres->purge)) { + list_del_init(&lockres->purge); + dlm->purge_count--; + } + __dlm_unhash_lockres(lockres); +} + +static void dlm_run_purge_list(struct dlm_ctxt *dlm, + int purge_now) +{ + unsigned int run_max, unused; + unsigned long purge_jiffies; + struct dlm_lock_resource *lockres; + + spin_lock(&dlm->spinlock); + run_max = dlm->purge_count; + + while(run_max && !list_empty(&dlm->purge_list)) { + run_max--; + + lockres = list_entry(dlm->purge_list.next, + struct dlm_lock_resource, purge); + + /* Status of the lockres *might* change so double + * check. If the lockres is unused, holding the dlm + * spinlock will prevent people from getting and more + * refs on it -- there's no need to keep the lockres + * spinlock. */ + spin_lock(&lockres->spinlock); + unused = __dlm_lockres_unused(lockres); + spin_unlock(&lockres->spinlock); + + if (!unused) + continue; + + purge_jiffies = lockres->last_used + + msecs_to_jiffies(DLM_PURGE_INTERVAL_MS); + + /* Make sure that we want to be processing this guy at + * this time. */ + if (!purge_now && time_after(purge_jiffies, jiffies)) { + /* Since resources are added to the purge list + * in tail order, we can stop at the first + * unpurgable resource -- anyone added after + * him will have a greater last_used value */ + break; + } + + list_del_init(&lockres->purge); + dlm->purge_count--; + + /* This may drop and reacquire the dlm spinlock if it + * has to do migration. */ + mlog(0, "calling dlm_purge_lockres!\n"); + dlm_purge_lockres(dlm, lockres); + mlog(0, "DONE calling dlm_purge_lockres!\n"); + + /* Avoid adding any scheduling latencies */ + cond_resched_lock(&dlm->spinlock); + } + + spin_unlock(&dlm->spinlock); +} + +static void dlm_shuffle_lists(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res) +{ + struct dlm_lock *lock, *target; + struct list_head *iter; + struct list_head *head; + int can_grant = 1; + + //mlog(0, "res->lockname.len=%d\n", res->lockname.len); + //mlog(0, "res->lockname.name=%p\n", res->lockname.name); + //mlog(0, "shuffle res %.*s\n", res->lockname.len, + // res->lockname.name); + + /* because this function is called with the lockres + * spinlock, and because we know that it is not migrating/ + * recovering/in-progress, it is fine to reserve asts and + * basts right before queueing them all throughout */ + assert_spin_locked(&res->spinlock); + BUG_ON((res->state & (DLM_LOCK_RES_MIGRATING| + DLM_LOCK_RES_RECOVERING| + DLM_LOCK_RES_IN_PROGRESS))); + +converting: + if (list_empty(&res->converting)) + goto blocked; + mlog(0, "res %.*s has locks on a convert queue\n", res->lockname.len, + res->lockname.name); + + target = list_entry(res->converting.next, struct dlm_lock, list); + if (target->ml.convert_type == LKM_IVMODE) { + mlog(ML_ERROR, "%.*s: converting a lock with no " + "convert_type!\n", res->lockname.len, res->lockname.name); + BUG(); + } + head = &res->granted; + list_for_each(iter, head) { + lock = list_entry(iter, struct dlm_lock, list); + if (lock==target) + continue; + if (!dlm_lock_compatible(lock->ml.type, + target->ml.convert_type)) { + can_grant = 0; + /* queue the BAST if not already */ + if (lock->ml.highest_blocked == LKM_IVMODE) { + __dlm_lockres_reserve_ast(res); + dlm_queue_bast(dlm, lock); + } + /* update the highest_blocked if needed */ + if (lock->ml.highest_blocked < target->ml.convert_type) + lock->ml.highest_blocked = + target->ml.convert_type; + } + } + head = &res->converting; + list_for_each(iter, head) { + lock = list_entry(iter, struct dlm_lock, list); + if (lock==target) + continue; + if (!dlm_lock_compatible(lock->ml.type, + target->ml.convert_type)) { + can_grant = 0; + if (lock->ml.highest_blocked == LKM_IVMODE) { + __dlm_lockres_reserve_ast(res); + dlm_queue_bast(dlm, lock); + } + if (lock->ml.highest_blocked < target->ml.convert_type) + lock->ml.highest_blocked = + target->ml.convert_type; + } + } + + /* we can convert the lock */ + if (can_grant) { + spin_lock(&target->spinlock); + BUG_ON(target->ml.highest_blocked != LKM_IVMODE); + + mlog(0, "calling ast for converting lock: %.*s, have: %d, " + "granting: %d, node: %u\n", res->lockname.len, + res->lockname.name, target->ml.type, + target->ml.convert_type, target->ml.node); + + target->ml.type = target->ml.convert_type; + target->ml.convert_type = LKM_IVMODE; + list_del_init(&target->list); + list_add_tail(&target->list, &res->granted); + + BUG_ON(!target->lksb); + target->lksb->status = DLM_NORMAL; + + spin_unlock(&target->spinlock); + + __dlm_lockres_reserve_ast(res); + dlm_queue_ast(dlm, target); + /* go back and check for more */ + goto converting; + } + +blocked: + if (list_empty(&res->blocked)) + goto leave; + target = list_entry(res->blocked.next, struct dlm_lock, list); + + head = &res->granted; + list_for_each(iter, head) { + lock = list_entry(iter, struct dlm_lock, list); + if (lock==target) + continue; + if (!dlm_lock_compatible(lock->ml.type, target->ml.type)) { + can_grant = 0; + if (lock->ml.highest_blocked == LKM_IVMODE) { + __dlm_lockres_reserve_ast(res); + dlm_queue_bast(dlm, lock); + } + if (lock->ml.highest_blocked < target->ml.type) + lock->ml.highest_blocked = target->ml.type; + } + } + + head = &res->converting; + list_for_each(iter, head) { + lock = list_entry(iter, struct dlm_lock, list); + if (lock==target) + continue; + if (!dlm_lock_compatible(lock->ml.type, target->ml.type)) { + can_grant = 0; + if (lock->ml.highest_blocked == LKM_IVMODE) { + __dlm_lockres_reserve_ast(res); + dlm_queue_bast(dlm, lock); + } + if (lock->ml.highest_blocked < target->ml.type) + lock->ml.highest_blocked = target->ml.type; + } + } + + /* we can grant the blocked lock (only + * possible if converting list empty) */ + if (can_grant) { + spin_lock(&target->spinlock); + BUG_ON(target->ml.highest_blocked != LKM_IVMODE); + + mlog(0, "calling ast for blocked lock: %.*s, granting: %d, " + "node: %u\n", res->lockname.len, res->lockname.name, + target->ml.type, target->ml.node); + + // target->ml.type is already correct + list_del_init(&target->list); + list_add_tail(&target->list, &res->granted); + + BUG_ON(!target->lksb); + target->lksb->status = DLM_NORMAL; + + spin_unlock(&target->spinlock); + + __dlm_lockres_reserve_ast(res); + dlm_queue_ast(dlm, target); + /* go back and check for more */ + goto converting; + } + +leave: + return; +} + +/* must have NO locks when calling this with res !=NULL * */ +void dlm_kick_thread(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) +{ + mlog_entry("dlm=%p, res=%p\n", dlm, res); + if (res) { + spin_lock(&dlm->spinlock); + spin_lock(&res->spinlock); + __dlm_dirty_lockres(dlm, res); + spin_unlock(&res->spinlock); + spin_unlock(&dlm->spinlock); + } + wake_up(&dlm->dlm_thread_wq); +} + +void __dlm_dirty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) +{ + mlog_entry("dlm=%p, res=%p\n", dlm, res); + + assert_spin_locked(&dlm->spinlock); + assert_spin_locked(&res->spinlock); + + /* don't shuffle secondary queues */ + if ((res->owner == dlm->node_num) && + !(res->state & DLM_LOCK_RES_DIRTY)) { + list_add_tail(&res->dirty, &dlm->dirty_list); + res->state |= DLM_LOCK_RES_DIRTY; + } +} + + +/* Launch the NM thread for the mounted volume */ +int dlm_launch_thread(struct dlm_ctxt *dlm) +{ + mlog(0, "starting dlm thread...\n"); + + dlm->dlm_thread_task = kthread_run(dlm_thread, dlm, "dlm_thread"); + if (IS_ERR(dlm->dlm_thread_task)) { + mlog_errno(PTR_ERR(dlm->dlm_thread_task)); + dlm->dlm_thread_task = NULL; + return -EINVAL; + } + + return 0; +} + +void dlm_complete_thread(struct dlm_ctxt *dlm) +{ + if (dlm->dlm_thread_task) { + mlog(ML_KTHREAD, "waiting for dlm thread to exit\n"); + kthread_stop(dlm->dlm_thread_task); + dlm->dlm_thread_task = NULL; + } +} + +static int dlm_dirty_list_empty(struct dlm_ctxt *dlm) +{ + int empty; + + spin_lock(&dlm->spinlock); + empty = list_empty(&dlm->dirty_list); + spin_unlock(&dlm->spinlock); + + return empty; +} + +static void dlm_flush_asts(struct dlm_ctxt *dlm) +{ + int ret; + struct dlm_lock *lock; + struct dlm_lock_resource *res; + u8 hi; + + spin_lock(&dlm->ast_lock); + while (!list_empty(&dlm->pending_asts)) { + lock = list_entry(dlm->pending_asts.next, + struct dlm_lock, ast_list); + /* get an extra ref on lock */ + dlm_lock_get(lock); + res = lock->lockres; + mlog(0, "delivering an ast for this lockres\n"); + + BUG_ON(!lock->ast_pending); + + /* remove from list (including ref) */ + list_del_init(&lock->ast_list); + dlm_lock_put(lock); + spin_unlock(&dlm->ast_lock); + + if (lock->ml.node != dlm->node_num) { + ret = dlm_do_remote_ast(dlm, res, lock); + if (ret < 0) + mlog_errno(ret); + } else + dlm_do_local_ast(dlm, res, lock); + + spin_lock(&dlm->ast_lock); + + /* possible that another ast was queued while + * we were delivering the last one */ + if (!list_empty(&lock->ast_list)) { + mlog(0, "aha another ast got queued while " + "we were finishing the last one. will " + "keep the ast_pending flag set.\n"); + } else + lock->ast_pending = 0; + + /* drop the extra ref. + * this may drop it completely. */ + dlm_lock_put(lock); + dlm_lockres_release_ast(dlm, res); + } + + while (!list_empty(&dlm->pending_basts)) { + lock = list_entry(dlm->pending_basts.next, + struct dlm_lock, bast_list); + /* get an extra ref on lock */ + dlm_lock_get(lock); + res = lock->lockres; + + BUG_ON(!lock->bast_pending); + + /* get the highest blocked lock, and reset */ + spin_lock(&lock->spinlock); + BUG_ON(lock->ml.highest_blocked <= LKM_IVMODE); + hi = lock->ml.highest_blocked; + lock->ml.highest_blocked = LKM_IVMODE; + spin_unlock(&lock->spinlock); + + /* remove from list (including ref) */ + list_del_init(&lock->bast_list); + dlm_lock_put(lock); + spin_unlock(&dlm->ast_lock); + + mlog(0, "delivering a bast for this lockres " + "(blocked = %d\n", hi); + + if (lock->ml.node != dlm->node_num) { + ret = dlm_send_proxy_bast(dlm, res, lock, hi); + if (ret < 0) + mlog_errno(ret); + } else + dlm_do_local_bast(dlm, res, lock, hi); + + spin_lock(&dlm->ast_lock); + + /* possible that another bast was queued while + * we were delivering the last one */ + if (!list_empty(&lock->bast_list)) { + mlog(0, "aha another bast got queued while " + "we were finishing the last one. will " + "keep the bast_pending flag set.\n"); + } else + lock->bast_pending = 0; + + /* drop the extra ref. + * this may drop it completely. */ + dlm_lock_put(lock); + dlm_lockres_release_ast(dlm, res); + } + wake_up(&dlm->ast_wq); + spin_unlock(&dlm->ast_lock); +} + + +#define DLM_THREAD_TIMEOUT_MS (4 * 1000) +#define DLM_THREAD_MAX_DIRTY 100 +#define DLM_THREAD_MAX_ASTS 10 + +static int dlm_thread(void *data) +{ + struct dlm_lock_resource *res; + struct dlm_ctxt *dlm = data; + unsigned long timeout = msecs_to_jiffies(DLM_THREAD_TIMEOUT_MS); + + mlog(0, "dlm thread running for %s...\n", dlm->name); + + while (!kthread_should_stop()) { + int n = DLM_THREAD_MAX_DIRTY; + + /* dlm_shutting_down is very point-in-time, but that + * doesn't matter as we'll just loop back around if we + * get false on the leading edge of a state + * transition. */ + dlm_run_purge_list(dlm, dlm_shutting_down(dlm)); + + /* We really don't want to hold dlm->spinlock while + * calling dlm_shuffle_lists on each lockres that + * needs to have its queues adjusted and AST/BASTs + * run. So let's pull each entry off the dirty_list + * and drop dlm->spinlock ASAP. Once off the list, + * res->spinlock needs to be taken again to protect + * the queues while calling dlm_shuffle_lists. */ + spin_lock(&dlm->spinlock); + while (!list_empty(&dlm->dirty_list)) { + int delay = 0; + res = list_entry(dlm->dirty_list.next, + struct dlm_lock_resource, dirty); + + /* peel a lockres off, remove it from the list, + * unset the dirty flag and drop the dlm lock */ + BUG_ON(!res); + dlm_lockres_get(res); + + spin_lock(&res->spinlock); + res->state &= ~DLM_LOCK_RES_DIRTY; + list_del_init(&res->dirty); + spin_unlock(&res->spinlock); + spin_unlock(&dlm->spinlock); + + /* lockres can be re-dirtied/re-added to the + * dirty_list in this gap, but that is ok */ + + spin_lock(&res->spinlock); + if (res->owner != dlm->node_num) { + __dlm_print_one_lock_resource(res); + mlog(ML_ERROR, "inprog:%s, mig:%s, reco:%s, dirty:%s\n", + res->state & DLM_LOCK_RES_IN_PROGRESS ? "yes" : "no", + res->state & DLM_LOCK_RES_MIGRATING ? "yes" : "no", + res->state & DLM_LOCK_RES_RECOVERING ? "yes" : "no", + res->state & DLM_LOCK_RES_DIRTY ? "yes" : "no"); + } + BUG_ON(res->owner != dlm->node_num); + + /* it is now ok to move lockreses in these states + * to the dirty list, assuming that they will only be + * dirty for a short while. */ + if (res->state & (DLM_LOCK_RES_IN_PROGRESS | + DLM_LOCK_RES_MIGRATING | + DLM_LOCK_RES_RECOVERING)) { + /* move it to the tail and keep going */ + spin_unlock(&res->spinlock); + mlog(0, "delaying list shuffling for in-" + "progress lockres %.*s, state=%d\n", + res->lockname.len, res->lockname.name, + res->state); + delay = 1; + goto in_progress; + } + + /* at this point the lockres is not migrating/ + * recovering/in-progress. we have the lockres + * spinlock and do NOT have the dlm lock. + * safe to reserve/queue asts and run the lists. */ + + mlog(0, "calling dlm_shuffle_lists with dlm=%p, " + "res=%p\n", dlm, res); + + /* called while holding lockres lock */ + dlm_shuffle_lists(dlm, res); + spin_unlock(&res->spinlock); + + dlm_lockres_calc_usage(dlm, res); + +in_progress: + + spin_lock(&dlm->spinlock); + /* if the lock was in-progress, stick + * it on the back of the list */ + if (delay) { + spin_lock(&res->spinlock); + list_add_tail(&res->dirty, &dlm->dirty_list); + res->state |= DLM_LOCK_RES_DIRTY; + spin_unlock(&res->spinlock); + } + dlm_lockres_put(res); + + /* unlikely, but we may need to give time to + * other tasks */ + if (!--n) { + mlog(0, "throttling dlm_thread\n"); + break; + } + } + + spin_unlock(&dlm->spinlock); + dlm_flush_asts(dlm); + + /* yield and continue right away if there is more work to do */ + if (!n) { + yield(); + continue; + } + + wait_event_interruptible_timeout(dlm->dlm_thread_wq, + !dlm_dirty_list_empty(dlm) || + kthread_should_stop(), + timeout); + } + + mlog(0, "quitting DLM thread\n"); + return 0; +} diff --git a/fs/ocfs2/dlm/dlmunlock.c b/fs/ocfs2/dlm/dlmunlock.c new file mode 100644 index 0000000..cec2ce1 --- /dev/null +++ b/fs/ocfs2/dlm/dlmunlock.c @@ -0,0 +1,672 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmunlock.c + * + * underlying calls for unlocking locks + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + + +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/highmem.h> +#include <linux/utsname.h> +#include <linux/init.h> +#include <linux/sysctl.h> +#include <linux/random.h> +#include <linux/blkdev.h> +#include <linux/socket.h> +#include <linux/inet.h> +#include <linux/spinlock.h> +#include <linux/delay.h> + +#include "cluster/heartbeat.h" +#include "cluster/nodemanager.h" +#include "cluster/tcp.h" + +#include "dlmapi.h" +#include "dlmcommon.h" + +#define MLOG_MASK_PREFIX ML_DLM +#include "cluster/masklog.h" + +#define DLM_UNLOCK_FREE_LOCK 0x00000001 +#define DLM_UNLOCK_CALL_AST 0x00000002 +#define DLM_UNLOCK_REMOVE_LOCK 0x00000004 +#define DLM_UNLOCK_REGRANT_LOCK 0x00000008 +#define DLM_UNLOCK_CLEAR_CONVERT_TYPE 0x00000010 + + +static enum dlm_status dlm_get_cancel_actions(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, + struct dlm_lockstatus *lksb, + int *actions); +static enum dlm_status dlm_get_unlock_actions(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, + struct dlm_lockstatus *lksb, + int *actions); + +static enum dlm_status dlm_send_remote_unlock_request(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, + struct dlm_lockstatus *lksb, + int flags, + u8 owner); + + +/* + * according to the spec: + * http://opendlm.sourceforge.net/cvsmirror/opendlm/docs/dlmbook_final.pdf + * + * flags & LKM_CANCEL != 0: must be converting or blocked + * flags & LKM_CANCEL == 0: must be granted + * + * So to unlock a converting lock, you must first cancel the + * convert (passing LKM_CANCEL in flags), then call the unlock + * again (with no LKM_CANCEL in flags). + */ + + +/* + * locking: + * caller needs: none + * taken: res->spinlock and lock->spinlock taken and dropped + * held on exit: none + * returns: DLM_NORMAL, DLM_NOLOCKMGR, status from network + * all callers should have taken an extra ref on lock coming in + */ +static enum dlm_status dlmunlock_common(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, + struct dlm_lockstatus *lksb, + int flags, int *call_ast, + int master_node) +{ + enum dlm_status status; + int actions = 0; + int in_use; + u8 owner; + + mlog(0, "master_node = %d, valblk = %d\n", master_node, + flags & LKM_VALBLK); + + if (master_node) + BUG_ON(res->owner != dlm->node_num); + else + BUG_ON(res->owner == dlm->node_num); + + spin_lock(&dlm->spinlock); + /* We want to be sure that we're not freeing a lock + * that still has AST's pending... */ + in_use = !list_empty(&lock->ast_list); + spin_unlock(&dlm->spinlock); + if (in_use) { + mlog(ML_ERROR, "lockres %.*s: Someone is calling dlmunlock " + "while waiting for an ast!", res->lockname.len, + res->lockname.name); + return DLM_BADPARAM; + } + + spin_lock(&res->spinlock); + if (res->state & DLM_LOCK_RES_IN_PROGRESS) { + if (master_node) { + mlog(ML_ERROR, "lockres in progress!\n"); + spin_unlock(&res->spinlock); + return DLM_FORWARD; + } + /* ok for this to sleep if not in a network handler */ + __dlm_wait_on_lockres(res); + res->state |= DLM_LOCK_RES_IN_PROGRESS; + } + spin_lock(&lock->spinlock); + + if (res->state & DLM_LOCK_RES_RECOVERING) { + status = DLM_RECOVERING; + goto leave; + } + + + /* see above for what the spec says about + * LKM_CANCEL and the lock queue state */ + if (flags & LKM_CANCEL) + status = dlm_get_cancel_actions(dlm, res, lock, lksb, &actions); + else + status = dlm_get_unlock_actions(dlm, res, lock, lksb, &actions); + + if (status != DLM_NORMAL) + goto leave; + + /* By now this has been masked out of cancel requests. */ + if (flags & LKM_VALBLK) { + /* make the final update to the lvb */ + if (master_node) + memcpy(res->lvb, lksb->lvb, DLM_LVB_LEN); + else + flags |= LKM_PUT_LVB; /* let the send function + * handle it. */ + } + + if (!master_node) { + owner = res->owner; + /* drop locks and send message */ + if (flags & LKM_CANCEL) + lock->cancel_pending = 1; + else + lock->unlock_pending = 1; + spin_unlock(&lock->spinlock); + spin_unlock(&res->spinlock); + status = dlm_send_remote_unlock_request(dlm, res, lock, lksb, + flags, owner); + spin_lock(&res->spinlock); + spin_lock(&lock->spinlock); + /* if the master told us the lock was already granted, + * let the ast handle all of these actions */ + if (status == DLM_NORMAL && + lksb->status == DLM_CANCELGRANT) { + actions &= ~(DLM_UNLOCK_REMOVE_LOCK| + DLM_UNLOCK_REGRANT_LOCK| + DLM_UNLOCK_CLEAR_CONVERT_TYPE); + } + if (flags & LKM_CANCEL) + lock->cancel_pending = 0; + else + lock->unlock_pending = 0; + + } + + /* get an extra ref on lock. if we are just switching + * lists here, we dont want the lock to go away. */ + dlm_lock_get(lock); + + if (actions & DLM_UNLOCK_REMOVE_LOCK) { + list_del_init(&lock->list); + dlm_lock_put(lock); + } + if (actions & DLM_UNLOCK_REGRANT_LOCK) { + dlm_lock_get(lock); + list_add_tail(&lock->list, &res->granted); + } + if (actions & DLM_UNLOCK_CLEAR_CONVERT_TYPE) { + mlog(0, "clearing convert_type at %smaster node\n", + master_node ? "" : "non-"); + lock->ml.convert_type = LKM_IVMODE; + } + + /* remove the extra ref on lock */ + dlm_lock_put(lock); + +leave: + res->state &= ~DLM_LOCK_RES_IN_PROGRESS; + if (!dlm_lock_on_list(&res->converting, lock)) + BUG_ON(lock->ml.convert_type != LKM_IVMODE); + else + BUG_ON(lock->ml.convert_type == LKM_IVMODE); + spin_unlock(&lock->spinlock); + spin_unlock(&res->spinlock); + wake_up(&res->wq); + + /* let the caller's final dlm_lock_put handle the actual kfree */ + if (actions & DLM_UNLOCK_FREE_LOCK) { + /* this should always be coupled with list removal */ + BUG_ON(!(actions & DLM_UNLOCK_REMOVE_LOCK)); + mlog(0, "lock %"MLFu64" should be gone now! refs=%d\n", + lock->ml.cookie, atomic_read(&lock->lock_refs.refcount)-1); + dlm_lock_put(lock); + } + if (actions & DLM_UNLOCK_CALL_AST) + *call_ast = 1; + + /* if cancel or unlock succeeded, lvb work is done */ + if (status == DLM_NORMAL) + lksb->flags &= ~(DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB); + + return status; +} + +void dlm_commit_pending_unlock(struct dlm_lock_resource *res, + struct dlm_lock *lock) +{ + /* leave DLM_LKSB_PUT_LVB on the lksb so any final + * update of the lvb will be sent to the new master */ + list_del_init(&lock->list); +} + +void dlm_commit_pending_cancel(struct dlm_lock_resource *res, + struct dlm_lock *lock) +{ + list_del_init(&lock->list); + list_add_tail(&lock->list, &res->granted); + lock->ml.convert_type = LKM_IVMODE; +} + + +static inline enum dlm_status dlmunlock_master(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, + struct dlm_lockstatus *lksb, + int flags, + int *call_ast) +{ + return dlmunlock_common(dlm, res, lock, lksb, flags, call_ast, 1); +} + +static inline enum dlm_status dlmunlock_remote(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, + struct dlm_lockstatus *lksb, + int flags, int *call_ast) +{ + return dlmunlock_common(dlm, res, lock, lksb, flags, call_ast, 0); +} + +/* + * locking: + * caller needs: none + * taken: none + * held on exit: none + * returns: DLM_NORMAL, DLM_NOLOCKMGR, status from network + */ +static enum dlm_status dlm_send_remote_unlock_request(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, + struct dlm_lockstatus *lksb, + int flags, + u8 owner) +{ + struct dlm_unlock_lock unlock; + int tmpret; + enum dlm_status ret; + int status = 0; + struct kvec vec[2]; + size_t veclen = 1; + + mlog_entry("%.*s\n", res->lockname.len, res->lockname.name); + + memset(&unlock, 0, sizeof(unlock)); + unlock.node_idx = dlm->node_num; + unlock.flags = cpu_to_be32(flags); + unlock.cookie = lock->ml.cookie; + unlock.namelen = res->lockname.len; + memcpy(unlock.name, res->lockname.name, unlock.namelen); + + vec[0].iov_len = sizeof(struct dlm_unlock_lock); + vec[0].iov_base = &unlock; + + if (flags & LKM_PUT_LVB) { + /* extra data to send if we are updating lvb */ + vec[1].iov_len = DLM_LVB_LEN; + vec[1].iov_base = lock->lksb->lvb; + veclen++; + } + + tmpret = o2net_send_message_vec(DLM_UNLOCK_LOCK_MSG, dlm->key, + vec, veclen, owner, &status); + if (tmpret >= 0) { + // successfully sent and received + if (status == DLM_CANCELGRANT) + ret = DLM_NORMAL; + else if (status == DLM_FORWARD) { + mlog(0, "master was in-progress. retry\n"); + ret = DLM_FORWARD; + } else + ret = status; + lksb->status = status; + } else { + mlog_errno(tmpret); + if (dlm_is_host_down(tmpret)) { + /* NOTE: this seems strange, but it is what we want. + * when the master goes down during a cancel or + * unlock, the recovery code completes the operation + * as if the master had not died, then passes the + * updated state to the recovery master. this thread + * just needs to finish out the operation and call + * the unlockast. */ + ret = DLM_NORMAL; + } else { + /* something bad. this will BUG in ocfs2 */ + ret = dlm_err_to_dlm_status(tmpret); + } + lksb->status = ret; + } + + return ret; +} + +/* + * locking: + * caller needs: none + * taken: takes and drops res->spinlock + * held on exit: none + * returns: DLM_NORMAL, DLM_BADARGS, DLM_IVLOCKID, + * return value from dlmunlock_master + */ +int dlm_unlock_lock_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_unlock_lock *unlock = (struct dlm_unlock_lock *)msg->buf; + struct dlm_lock_resource *res = NULL; + struct list_head *iter; + struct dlm_lock *lock = NULL; + enum dlm_status status = DLM_NORMAL; + int found = 0, i; + struct dlm_lockstatus *lksb = NULL; + int ignore; + u32 flags; + struct list_head *queue; + + flags = be32_to_cpu(unlock->flags); + + if (flags & LKM_GET_LVB) { + mlog(ML_ERROR, "bad args! GET_LVB specified on unlock!\n"); + return DLM_BADARGS; + } + + if ((flags & (LKM_PUT_LVB|LKM_CANCEL)) == (LKM_PUT_LVB|LKM_CANCEL)) { + mlog(ML_ERROR, "bad args! cannot modify lvb on a CANCEL " + "request!\n"); + return DLM_BADARGS; + } + + if (unlock->namelen > DLM_LOCKID_NAME_MAX) { + mlog(ML_ERROR, "Invalid name length in unlock handler!\n"); + return DLM_IVBUFLEN; + } + + if (!dlm_grab(dlm)) + return DLM_REJECTED; + + mlog_bug_on_msg(!dlm_domain_fully_joined(dlm), + "Domain %s not fully joined!\n", dlm->name); + + mlog(0, "lvb: %s\n", flags & LKM_PUT_LVB ? "put lvb" : "none"); + + res = dlm_lookup_lockres(dlm, unlock->name, unlock->namelen); + if (!res) { + /* We assume here that a no lock resource simply means + * it was migrated away and destroyed before the other + * node could detect it. */ + mlog(0, "returning DLM_FORWARD -- res no longer exists\n"); + status = DLM_FORWARD; + goto not_found; + } + + queue=&res->granted; + found = 0; + spin_lock(&res->spinlock); + if (res->state & DLM_LOCK_RES_RECOVERING) { + spin_unlock(&res->spinlock); + mlog(0, "returning DLM_RECOVERING\n"); + status = DLM_RECOVERING; + goto leave; + } + + if (res->state & DLM_LOCK_RES_MIGRATING) { + spin_unlock(&res->spinlock); + mlog(0, "returning DLM_MIGRATING\n"); + status = DLM_MIGRATING; + goto leave; + } + + if (res->owner != dlm->node_num) { + spin_unlock(&res->spinlock); + mlog(0, "returning DLM_FORWARD -- not master\n"); + status = DLM_FORWARD; + goto leave; + } + + for (i=0; i<3; i++) { + list_for_each(iter, queue) { + lock = list_entry(iter, struct dlm_lock, list); + if (lock->ml.cookie == unlock->cookie && + lock->ml.node == unlock->node_idx) { + dlm_lock_get(lock); + found = 1; + break; + } + } + if (found) + break; + /* scan granted -> converting -> blocked queues */ + queue++; + } + spin_unlock(&res->spinlock); + if (!found) { + status = DLM_IVLOCKID; + goto not_found; + } + + /* lock was found on queue */ + lksb = lock->lksb; + /* unlockast only called on originating node */ + if (flags & LKM_PUT_LVB) { + lksb->flags |= DLM_LKSB_PUT_LVB; + memcpy(&lksb->lvb[0], &unlock->lvb[0], DLM_LVB_LEN); + } + + /* if this is in-progress, propagate the DLM_FORWARD + * all the way back out */ + status = dlmunlock_master(dlm, res, lock, lksb, flags, &ignore); + if (status == DLM_FORWARD) + mlog(0, "lockres is in progress\n"); + + if (flags & LKM_PUT_LVB) + lksb->flags &= ~DLM_LKSB_PUT_LVB; + + dlm_lockres_calc_usage(dlm, res); + dlm_kick_thread(dlm, res); + +not_found: + if (!found) + mlog(ML_ERROR, "failed to find lock to unlock! " + "cookie=%"MLFu64"\n", + unlock->cookie); + else { + /* send the lksb->status back to the other node */ + status = lksb->status; + dlm_lock_put(lock); + } + +leave: + if (res) + dlm_lockres_put(res); + + dlm_put(dlm); + + return status; +} + + +static enum dlm_status dlm_get_cancel_actions(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, + struct dlm_lockstatus *lksb, + int *actions) +{ + enum dlm_status status; + + if (dlm_lock_on_list(&res->blocked, lock)) { + /* cancel this outright */ + lksb->status = DLM_NORMAL; + status = DLM_NORMAL; + *actions = (DLM_UNLOCK_CALL_AST | + DLM_UNLOCK_REMOVE_LOCK); + } else if (dlm_lock_on_list(&res->converting, lock)) { + /* cancel the request, put back on granted */ + lksb->status = DLM_NORMAL; + status = DLM_NORMAL; + *actions = (DLM_UNLOCK_CALL_AST | + DLM_UNLOCK_REMOVE_LOCK | + DLM_UNLOCK_REGRANT_LOCK | + DLM_UNLOCK_CLEAR_CONVERT_TYPE); + } else if (dlm_lock_on_list(&res->granted, lock)) { + /* too late, already granted. DLM_CANCELGRANT */ + lksb->status = DLM_CANCELGRANT; + status = DLM_NORMAL; + *actions = DLM_UNLOCK_CALL_AST; + } else { + mlog(ML_ERROR, "lock to cancel is not on any list!\n"); + lksb->status = DLM_IVLOCKID; + status = DLM_IVLOCKID; + *actions = 0; + } + return status; +} + +static enum dlm_status dlm_get_unlock_actions(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_lock *lock, + struct dlm_lockstatus *lksb, + int *actions) +{ + enum dlm_status status; + + /* unlock request */ + if (!dlm_lock_on_list(&res->granted, lock)) { + lksb->status = DLM_DENIED; + status = DLM_DENIED; + dlm_error(status); + *actions = 0; + } else { + /* unlock granted lock */ + lksb->status = DLM_NORMAL; + status = DLM_NORMAL; + *actions = (DLM_UNLOCK_FREE_LOCK | + DLM_UNLOCK_CALL_AST | + DLM_UNLOCK_REMOVE_LOCK); + } + return status; +} + +/* there seems to be no point in doing this async + * since (even for the remote case) there is really + * no work to queue up... so just do it and fire the + * unlockast by hand when done... */ +enum dlm_status dlmunlock(struct dlm_ctxt *dlm, struct dlm_lockstatus *lksb, + int flags, dlm_astunlockfunc_t *unlockast, void *data) +{ + enum dlm_status status; + struct dlm_lock_resource *res; + struct dlm_lock *lock = NULL; + int call_ast, is_master; + + mlog_entry_void(); + + if (!lksb) { + dlm_error(DLM_BADARGS); + return DLM_BADARGS; + } + + if (flags & ~(LKM_CANCEL | LKM_VALBLK | LKM_INVVALBLK)) { + dlm_error(DLM_BADPARAM); + return DLM_BADPARAM; + } + + if ((flags & (LKM_VALBLK | LKM_CANCEL)) == (LKM_VALBLK | LKM_CANCEL)) { + mlog(0, "VALBLK given with CANCEL: ignoring VALBLK\n"); + flags &= ~LKM_VALBLK; + } + + if (!lksb->lockid || !lksb->lockid->lockres) { + dlm_error(DLM_BADPARAM); + return DLM_BADPARAM; + } + + lock = lksb->lockid; + BUG_ON(!lock); + dlm_lock_get(lock); + + res = lock->lockres; + BUG_ON(!res); + dlm_lockres_get(res); +retry: + call_ast = 0; + /* need to retry up here because owner may have changed */ + mlog(0, "lock=%p res=%p\n", lock, res); + + spin_lock(&res->spinlock); + is_master = (res->owner == dlm->node_num); + spin_unlock(&res->spinlock); + + if (is_master) { + status = dlmunlock_master(dlm, res, lock, lksb, flags, + &call_ast); + mlog(0, "done calling dlmunlock_master: returned %d, " + "call_ast is %d\n", status, call_ast); + } else { + status = dlmunlock_remote(dlm, res, lock, lksb, flags, + &call_ast); + mlog(0, "done calling dlmunlock_remote: returned %d, " + "call_ast is %d\n", status, call_ast); + } + + if (status == DLM_RECOVERING || + status == DLM_MIGRATING || + status == DLM_FORWARD) { + /* We want to go away for a tiny bit to allow recovery + * / migration to complete on this resource. I don't + * know of any wait queue we could sleep on as this + * may be happening on another node. Perhaps the + * proper solution is to queue up requests on the + * other end? */ + + /* do we want to yield(); ?? */ + msleep(50); + + mlog(0, "retrying unlock due to pending recovery/" + "migration/in-progress\n"); + goto retry; + } + + if (call_ast) { + mlog(0, "calling unlockast(%p, %d)\n", data, lksb->status); + if (is_master) { + /* it is possible that there is one last bast + * pending. make sure it is flushed, then + * call the unlockast. + * not an issue if this is a mastered remotely, + * since this lock has been removed from the + * lockres queues and cannot be found. */ + dlm_kick_thread(dlm, NULL); + wait_event(dlm->ast_wq, + dlm_lock_basts_flushed(dlm, lock)); + } + (*unlockast)(data, lksb->status); + } + + if (status == DLM_NORMAL) { + mlog(0, "kicking the thread\n"); + dlm_kick_thread(dlm, res); + } else + dlm_error(status); + + dlm_lockres_calc_usage(dlm, res); + dlm_lockres_put(res); + dlm_lock_put(lock); + + mlog(0, "returning status=%d!\n", status); + return status; +} +EXPORT_SYMBOL_GPL(dlmunlock); + diff --git a/fs/ocfs2/dlm/dlmver.c b/fs/ocfs2/dlm/dlmver.c new file mode 100644 index 0000000..7ef2653 --- /dev/null +++ b/fs/ocfs2/dlm/dlmver.c @@ -0,0 +1,42 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmver.c + * + * version string + * + * Copyright (C) 2002, 2005 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#include <linux/module.h> +#include <linux/kernel.h> + +#include "dlmver.h" + +#define DLM_BUILD_VERSION "1.3.3" + +#define VERSION_STR "OCFS2 DLM " DLM_BUILD_VERSION + +void dlm_print_version(void) +{ + printk(KERN_INFO "%s\n", VERSION_STR); +} + +MODULE_DESCRIPTION(VERSION_STR); + +MODULE_VERSION(DLM_BUILD_VERSION); diff --git a/fs/ocfs2/dlm/dlmver.h b/fs/ocfs2/dlm/dlmver.h new file mode 100644 index 0000000..f674aee --- /dev/null +++ b/fs/ocfs2/dlm/dlmver.h @@ -0,0 +1,31 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmfsver.h + * + * Function prototypes + * + * Copyright (C) 2005 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#ifndef DLM_VER_H +#define DLM_VER_H + +void dlm_print_version(void); + +#endif /* DLM_VER_H */ |