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path: root/fs/ceph/inode.c
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2013-09-06ceph: remove ceph_lookup_inode()Yan, Zheng
commit 6f60f889 (ceph: fix freeing inode vs removing session caps race) introduced ceph_lookup_inode(). But there is already a ceph_find_inode() which provides similar function. So remove ceph_lookup_inode(), use ceph_find_inode() instead. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Alex Elder <alex.elder@linary.org> Reviewed-by: Sage Weil <sage@inktank.com>
2013-09-06ceph: use fscache as a local presisent cacheMilosz Tanski
Adding support for fscache to the Ceph filesystem. This would bring it to on par with some of the other network filesystems in Linux (like NFS, AFS, etc...) In order to mount the filesystem with fscache the 'fsc' mount option must be passed. Signed-off-by: Milosz Tanski <milosz@adfin.com> Signed-off-by: Sage Weil <sage@inktank.com>
2013-08-15ceph: introduce i_truncate_mutexYan, Zheng
I encountered below deadlock when running fsstress wmtruncate work truncate MDS --------------- ------------------ -------------------------- lock i_mutex <- truncate file lock i_mutex (blocked) <- revoking Fcb (filelock to MIX) send request -> handle request (xlock filelock) At the initial time, there are some dirty pages in the page cache. When the kclient receives the truncate message, it reduces inode size and creates some 'out of i_size' dirty pages. wmtruncate work can't truncate these dirty pages because it's blocked by the i_mutex. Later when the kclient receives the cap message that revokes Fcb caps, It can't flush all dirty pages because writepages() only flushes dirty pages within the inode size. When the MDS handles the 'truncate' request from kclient, it waits for the filelock to become stable. But the filelock is stuck in unstable state because it can't finish revoking kclient's Fcb caps. The truncate pagecache locking has already caused lots of trouble for use. I think it's time simplify it by introducing a new mutex. We use the new mutex to prevent concurrent truncate_inode_pages(). There is no need to worry about race between buffered write and truncate_inode_pages(), because our "get caps" mechanism prevents them from concurrent execution. Reviewed-by: Sage Weil <sage@inktank.com> Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2013-08-15Merge remote-tracking branch 'linus/master' into testingSage Weil
2013-08-10ceph: fix freeing inode vs removing session caps raceYan, Zheng
remove_session_caps() uses iterate_session_caps() to remove caps, but iterate_session_caps() skips inodes that are being deleted. So session->s_nr_caps can be non-zero after iterate_session_caps() return. We can fix the issue by waiting until deletions are complete. __wait_on_freeing_inode() is designed for the job, but it is not exported, so we use lookup inode function to access it. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2013-08-10ceph: wake up writer if vmtruncate work get blockedYan, Zheng
To write data, the writer first acquires the i_mutex, then try getting caps. The writer may sleep while holding the i_mutex. If the MDS revokes Fb cap in this case, vmtruncate work can't do its job because i_mutex is locked. We should wake up the writer and let it truncate the pages. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Sage Weil <sage@inktank.com>
2013-07-09Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client Pull Ceph updates from Sage Weil: "There is some follow-on RBD cleanup after the last window's code drop, a series from Yan fixing multi-mds behavior in cephfs, and then a sprinkling of bug fixes all around. Some warnings, sleeping while atomic, a null dereference, and cleanups" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (36 commits) libceph: fix invalid unsigned->signed conversion for timespec encoding libceph: call r_unsafe_callback when unsafe reply is received ceph: fix race between cap issue and revoke ceph: fix cap revoke race ceph: fix pending vmtruncate race ceph: avoid accessing invalid memory libceph: Fix NULL pointer dereference in auth client code ceph: Reconstruct the func ceph_reserve_caps. ceph: Free mdsc if alloc mdsc->mdsmap failed. ceph: remove sb_start/end_write in ceph_aio_write. ceph: avoid meaningless calling ceph_caps_revoking if sync_mode == WB_SYNC_ALL. ceph: fix sleeping function called from invalid context. ceph: move inode to proper flushing list when auth MDS changes rbd: fix a couple warnings ceph: clear migrate seq when MDS restarts ceph: check migrate seq before changing auth cap ceph: fix race between page writeback and truncate ceph: reset iov_len when discarding cap release messages ceph: fix cap release race libceph: fix truncate size calculation ...
2013-07-05helper for reading ->d_countAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-07-03ceph: fix pending vmtruncate raceYan, Zheng
The locking order for pending vmtruncate is wrong, it can lead to following race: write wmtruncate work ------------------------ ---------------------- lock i_mutex check i_truncate_pending check i_truncate_pending truncate_inode_pages() lock i_mutex (blocked) copy data to page cache unlock i_mutex truncate_inode_pages() The fix is take i_mutex before calling __ceph_do_pending_vmtruncate() Fixes: http://tracker.ceph.com/issues/5453 Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Sage Weil <sage@inktank.com>
2013-05-02ceph: fix symlink inode operationsYan, Zheng
add getattr/setattr and xattrs related methods. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-02ceph: use i_release_count to indicate dir's completenessYan, Zheng
Current ceph code tracks directory's completeness in two places. ceph_readdir() checks i_release_count to decide if it can set the I_COMPLETE flag in i_ceph_flags. All other places check the I_COMPLETE flag. This indirection introduces locking complexity. This patch adds a new variable i_complete_count to ceph_inode_info. Set i_release_count's value to it when marking a directory complete. By comparing the two variables, we know if a directory is complete Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2013-05-02ceph: acquire i_mutex in __ceph_do_pending_vmtruncateYan, Zheng
make __ceph_do_pending_vmtruncate() acquire the i_mutex if the caller does not hold the i_mutex, so ceph_aio_read() can call safely. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-02ceph: use I_COMPLETE inode flag instead of D_COMPLETE flagYan, Zheng
commit c6ffe10015 moved the flag that tracks if the dcache contents for a directory are complete to dentry. The problem is there are lots of places that use ceph_dir_{set,clear,test}_complete() while holding i_ceph_lock. but ceph_dir_{set,clear,test}_complete() may sleep because they call dput(). This patch basically reverts that commit. For ceph_d_prune(), it's called with both the dentry to prune and the parent dentry are locked. So it's safe to access the parent dentry's d_inode and clear I_COMPLETE flag. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Greg Farnum <greg@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2013-02-27Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile (part one) from Al Viro: "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent locking violations, etc. The most visible changes here are death of FS_REVAL_DOT (replaced with "has ->d_weak_revalidate()") and a new helper getting from struct file to inode. Some bits of preparation to xattr method interface changes. Misc patches by various people sent this cycle *and* ocfs2 fixes from several cycles ago that should've been upstream right then. PS: the next vfs pile will be xattr stuff." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) saner proc_get_inode() calling conventions proc: avoid extra pde_put() in proc_fill_super() fs: change return values from -EACCES to -EPERM fs/exec.c: make bprm_mm_init() static ocfs2/dlm: use GFP_ATOMIC inside a spin_lock ocfs2: fix possible use-after-free with AIO ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero target: writev() on single-element vector is pointless export kernel_write(), convert open-coded instances fs: encode_fh: return FILEID_INVALID if invalid fid_type kill f_vfsmnt vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op nfsd: handle vfs_getattr errors in acl protocol switch vfs_getattr() to struct path default SET_PERSONALITY() in linux/elf.h ceph: prepopulate inodes only when request is aborted d_hash_and_lookup(): export, switch open-coded instances 9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate() 9p: split dropping the acls from v9fs_set_create_acl() ...
2013-02-26ceph: prepopulate inodes only when request is abortedSage Weil
If r_aborted is true, we do not hold the dir i_mutex, and cannot touch the dcache. However, we still need to update the inodes with the state returned by the MDS. Reported-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Sage Weil <sage@inktank.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-12ceph: Convert kuids and kgids before printing them.Eric W. Biederman
Before printing kuid and kgids values convert them into the initial user namespace. Cc: Sage Weil <sage@inktank.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-12ceph: Translate inode uid and gid attributes to/from kuids and kgids.Eric W. Biederman
- In fill_inode() transate uids and gids in the initial user namespace into kuids and kgids stored in inode->i_uid and inode->i_gid. - In ceph_setattr() if they have changed convert inode->i_uid and inode->i_gid into initial user namespace uids and gids for transmission. Cc: Sage Weil <sage@inktank.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-12-20Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client Pull Ceph update from Sage Weil: "There are a few different groups of commits here. The largest is Alex's ongoing work to enable the coming RBD features (cloning, striping). There is some cleanup in libceph that goes along with it. Cyril and David have fixed some problems with NFS reexport (leaking dentries and page locks), and there is a batch of patches from Yan fixing problems with the fs client when running against a clustered MDS. There are a few bug fixes mixed in for good measure, many of which will be going to the stable trees once they're upstream. My apologies for the late pull. There is still a gremlin in the rbd map/unmap code and I was hoping to include the fix for that as well, but we haven't been able to confirm the fix is correct yet; I'll send that in a separate pull once it's nailed down." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (68 commits) rbd: get rid of rbd_{get,put}_dev() libceph: register request before unregister linger libceph: don't use rb_init_node() in ceph_osdc_alloc_request() libceph: init event->node in ceph_osdc_create_event() libceph: init osd->o_node in create_osd() libceph: report connection fault with warning libceph: socket can close in any connection state rbd: don't use ENOTSUPP rbd: remove linger unconditionally rbd: get rid of RBD_MAX_SEG_NAME_LEN libceph: avoid using freed osd in __kick_osd_requests() ceph: don't reference req after put rbd: do not allow remove of mounted-on image libceph: Unlock unprocessed pages in start_read() error path ceph: call handle_cap_grant() for cap import message ceph: Fix __ceph_do_pending_vmtruncate ceph: Don't add dirty inode to dirty list if caps is in migration ceph: Fix infinite loop in __wake_requests ceph: Don't update i_max_size when handling non-auth cap bdi_register: add __printf verification, fix arg mismatch ...
2012-12-13ceph: Fix __ceph_do_pending_vmtruncateYan, Zheng
we should set i_truncate_pending to 0 after page cache is truncated to i_truncate_size Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Signed-off-by: Sage Weil <sage@inktank.com>
2012-09-27ceph: don't abuse d_delete() on failure exitsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-08-21ceph: tolerate (and warn on) extraneous dentry from mdsSage Weil
If the MDS gives us a dentry and we weren't prepared to handle it, WARN_ON_ONCE instead of crashing. Reported-by: Yan, Zheng <zheng.z.yan@intel.com> Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-03-22ceph: avoid panic with mismatched symlink sizes in fill_inode()Xi Wang
Return -EINVAL rather than panic if iinfo->symlink_len and inode->i_size do not match. Also use kstrndup rather than kmalloc/memcpy. Signed-off-by: Xi Wang <xi.wang@gmail.com> Reviewed-by: Alex Elder <elder@dreamhost.com>
2012-01-13Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: ceph: ensure prealloc_blob is in place when removing xattr rbd: initialize snap_rwsem in rbd_add() ceph: enable/disable dentry complete flags via mount option vfs: export symbol d_find_any_alias() ceph: always initialize the dentry in open_root_dentry() libceph: remove useless return value for osd_client __send_request() ceph: avoid iput() while holding spinlock in ceph_dir_fsync ceph: avoid useless dget/dput in encode_fh ceph: dereference pointer after checking for NULL crush: fix force for non-root TAKE ceph: remove unnecessary d_fsdata conditional checks ceph: Use kmemdup rather than duplicating its implementation Fix up conflicts in fs/ceph/super.c (d_alloc_root() failure handling vs always initialize the dentry in open_root_dentry)
2012-01-10ceph: dereference pointer after checking for NULLYehuda Sadeh
moved dereference after BUG_ON Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
2012-01-04vfs: fix the stupidity with i_dentry in inode destructorsAl Viro
Seeing that just about every destructor got that INIT_LIST_HEAD() copied into it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once(); the cost of taking it into inode_init_always() will be negligible for pipes and sockets and negative for everything else. Not to mention the removal of boilerplate code from ->destroy_inode() instances... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-12-07ceph: use i_ceph_lock instead of i_lockSage Weil
We have been using i_lock to protect all kinds of data structures in the ceph_inode_info struct, including lists of inodes that we need to iterate over while avoiding races with inode destruction. That requires grabbing a reference to the inode with the list lock protected, but igrab() now takes i_lock to check the inode flags. Changing the list lock ordering would be a painful process. However, using a ceph-specific i_ceph_lock in the ceph inode instead of i_lock is a simple mechanical change and avoids the ordering constraints imposed by igrab(). Reported-by: Amon Ott <a.ott@m-privacy.de> Signed-off-by: Sage Weil <sage@newdream.net>
2011-11-06ceph: fix iput race when queueing inode workSage Weil
If we queue a work item that calls iput(), make sure we ihold() before attempting to queue work. Otherwise our queued work might miraculously run before we notice the queue_work() succeeded and call ihold(), allowing the inode to be destroyed. That is, instead of if (queue_work(...)) ihold(); we need to do ihold(); if (!queue_work(...)) iput(); Reported-by: Amon Ott <a.ott@m-privacy.de> Signed-off-by: Sage Weil <sage@newdream.net>
2011-11-06ceph: use new D_COMPLETE dentry flagSage Weil
We used to use a flag on the directory inode to track whether the dcache contents for a directory were a complete cached copy. Switch to a dentry flag CEPH_D_COMPLETE that is safely updated by ->d_prune(). Signed-off-by: Sage Weil <sage@newdream.net>
2011-11-02filesystems: add set_nlink()Miklos Szeredi
Replace remaining direct i_nlink updates with a new set_nlink() updater function. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2011-10-25Revert "ceph: don't truncate dirty pages in invalidate work thread"Sage Weil
This reverts commit c9af9fb68e01eb2c2165e1bc45cfeeed510c64e6. We need to block and truncate all pages in order to reliably invalidate them. Otherwise, we could: - have some uptodate pages in the cache - queue an invalidate - write(2) locks some pages - invalidate_work skips them - write(2) only overwrites part of the page - page now dirty and uptodate -> partial leakage of invalidated data It's not entirely clear why we started skipping locked pages in the first place. I just ran this through fsx and didn't see any problems. Signed-off-by: Sage Weil <sage@newdream.net>
2011-07-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (23 commits) ceph: document unlocked d_parent accesses ceph: explicitly reference rename old_dentry parent dir in request ceph: document locking for ceph_set_dentry_offset ceph: avoid d_parent in ceph_dentry_hash; fix ceph_encode_fh() hashing bug ceph: protect d_parent access in ceph_d_revalidate ceph: protect access to d_parent ceph: handle racing calls to ceph_init_dentry ceph: set dir complete frag after adding capability rbd: set blk_queue request sizes to object size ceph: set up readahead size when rsize is not passed rbd: cancel watch request when releasing the device ceph: ignore lease mask ceph: fix ceph_lookup_open intent usage ceph: only link open operations to directory unsafe list if O_CREAT|O_TRUNC ceph: fix bad parent_inode calc in ceph_lookup_open ceph: avoid carrying Fw cap during write into page cache libceph: don't time out osd requests that haven't been received ceph: report f_bfree based on kb_avail rather than diffing. ceph: only queue capsnap if caps are dirty ceph: fix snap writeback when racing with writes ...
2011-07-26ceph: document locking for ceph_set_dentry_offsetSage Weil
Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net> Signed-off-by: Sage Weil <sage@newdream.net>
2011-07-26ceph: protect access to d_parentSage Weil
d_parent is protected by d_lock: use it when looking up a dentry's parent directory inode. Also take a reference and drop it in the caller to avoid a use-after-free. Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net> Signed-off-by: Sage Weil <sage@newdream.net>
2011-07-26ceph: set dir complete frag after adding capabilitySage Weil
Curretly ceph_add_cap clears the complete bit if we are newly issued the FILE_SHARED cap, which is normally the case for a newly issue cap on a new directory. That means we clear the just-set bit. Move the check that sets the flag to after the cap is added/updated. Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net> Signed-off-by: Sage Weil <sage@newdream.net>
2011-07-26ceph: ignore lease maskSage Weil
The lease mask is no longer used (and it changed a while back). Instead, use a non-zero duration to indicate that there is a lease being issued. Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net> Signed-off-by: Sage Weil <sage@newdream.net>
2011-07-20->permission() sanitizing: don't pass flags to ->permission()Al Viro
not used by the instances anymore. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20->permission() sanitizing: don't pass flags to generic_permission()Al Viro
redundant; all callers get it duplicated in mask & MAY_NOT_BLOCK and none of them removes that bit. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20kill check_acl callback of generic_permission()Al Viro
its value depends only on inode and does not change; we might as well store it in ->i_op->check_acl and be done with that. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-06-08ceph: use ihold when we already have an inode refSage Weil
We should use ihold whenever we already have a stable inode ref, even when we aren't holding i_lock. This avoids adding new and unnecessary locking dependencies. Signed-off-by: Sage Weil <sage@newdream.net>
2011-05-11ceph: do not use i_wrbuffer_ref as refcount for Fb capHenry C Chang
We increments i_wrbuffer_ref when taking the Fb cap. This breaks the dirty page accounting and causes looping in __ceph_do_pending_vmtruncate, and ceph client hangs. This bug can be reproduced occasionally by running blogbench. Add a new field i_wb_ref to inode and dedicate it to Fb reference counting. Signed-off-by: Henry C Chang <henry.cy.chang@gmail.com> Signed-off-by: Sage Weil <sage@newdream.net>
2011-05-04ceph: do not call __mark_dirty_inode under i_lockSage Weil
The __mark_dirty_inode helper now takes i_lock as of 250df6ed. Fix the one ceph callers that held i_lock (__ceph_mark_dirty_caps) to return the flags value so that the callers can do it outside of i_lock. Signed-off-by: Sage Weil <sage@newdream.net>
2011-03-21ceph: add ino32 mount optionYehuda Sadeh
The ino32 mount option forces the ceph fs to report 32 bit ino values. This is useful for 64 bit kernels with 32 bit userspace. Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
2011-03-15ceph: preserve I_COMPLETE across renameSage Weil
d_move puts the renamed dentry at the end of d_subdirs, screwing with our cached dentry directory offsets. We were just clearing I_COMPLETE to avoid any possibility of trouble. However, assigning the renamed dentry an offset at the end of the directory (to match it's new d_subdirs position) is sufficient to maintain correct behavior and hold onto I_COMPLETE. This is especially important for workloads like rsync, which renames files into place. Before, we would lose I_COMPLETE and do MDS lookups for each file. With this patch we only talk to the MDS on create and rename. Signed-off-by: Sage Weil <sage@newdream.net>
2011-03-03ceph: do not set I_COMPLETESage Weil
Do not set the I_COMPLETE flag on directories until we resolve races with dcache pruning. Signed-off-by: Sage Weil <sage@newdream.net>
2011-01-28Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: ceph: avoid picking MDS that is not active ceph: avoid immediate cap check after import ceph: fix flushing of caps vs cap import ceph: fix erroneous cap flush to non-auth mds ceph: fix cap_wanted_delay_{min,max} mount option initialization ceph: fix xattr rbtree search ceph: fix getattr on directory when using norbytes
2011-01-13ceph: fix getattr on directory when using norbytesYehuda Sadeh
The norbytes mount option was broken, and when doing getattr on a directory it return the rbytes instead of the number of entities. This commit fixes it. Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net> Signed-off-by: Sage Weil <sage@newdream.net>
2011-01-13Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: rbd: fix cleanup when trying to mount inexistent image net/ceph: make ceph_msgr_wq non-reentrant ceph: fsc->*_wq's aren't used in memory reclaim path ceph: Always free allocated memory in osdmap_decode() ceph: Makefile: Remove unnessary code ceph: associate requests with opening sessions ceph: drop redundant r_mds field ceph: implement DIRLAYOUTHASH feature to get dir layout from MDS ceph: add dir_layout to inode
2011-01-12ceph: implement DIRLAYOUTHASH feature to get dir layout from MDSSage Weil
This implements the DIRLAYOUTHASH protocol feature, which passes the dir layout over the wire from the MDS. This gives the client knowledge of the correct hash function to use for mapping dentries among dir fragments. Note that if this feature is _not_ present on the client but is on the MDS, the client may misdirect requests. This will result in a forward and degrade performance. It may also result in inaccurate NFS filehandle generation, which will prevent fh resolution when the inode is not present in the client cache and the parent directories have been fragmented. Signed-off-by: Sage Weil <sage@newdream.net>
2011-01-12ceph: add dir_layout to inodeSage Weil
Add a ceph_dir_layout to the inode, and calculate dentry hash values based on the parent directory's specified dir_hash function. This is needed because the old default Linux dcache hash function is extremely week and leads to a poor distribution of files among dir fragments. Signed-off-by: Sage Weil <sage@newdream.net>
2011-01-07fs: provide rcu-walk aware permission i_opsNick Piggin
Signed-off-by: Nick Piggin <npiggin@kernel.dk>