diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/xfs/xfs_rename.c | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/xfs/xfs_rename.c')
-rw-r--r-- | fs/xfs/xfs_rename.c | 673 |
1 files changed, 673 insertions, 0 deletions
diff --git a/fs/xfs/xfs_rename.c b/fs/xfs/xfs_rename.c new file mode 100644 index 0000000..cb13f9a --- /dev/null +++ b/fs/xfs/xfs_rename.c @@ -0,0 +1,673 @@ +/* + * Copyright (c) 2000-2003 Silicon Graphics, Inc. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it would be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + * + * Further, this software is distributed without any warranty that it is + * free of the rightful claim of any third person regarding infringement + * or the like. Any license provided herein, whether implied or + * otherwise, applies only to this software file. Patent licenses, if + * any, provided herein do not apply to combinations of this program with + * other software, or any other product whatsoever. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write the Free Software Foundation, Inc., 59 + * Temple Place - Suite 330, Boston MA 02111-1307, USA. + * + * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy, + * Mountain View, CA 94043, or: + * + * http://www.sgi.com + * + * For further information regarding this notice, see: + * + * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/ + */ + +#include "xfs.h" +#include "xfs_macros.h" +#include "xfs_types.h" +#include "xfs_inum.h" +#include "xfs_log.h" +#include "xfs_trans.h" +#include "xfs_sb.h" +#include "xfs_dir.h" +#include "xfs_dir2.h" +#include "xfs_dmapi.h" +#include "xfs_mount.h" +#include "xfs_bmap_btree.h" +#include "xfs_attr_sf.h" +#include "xfs_dir_sf.h" +#include "xfs_dir2_sf.h" +#include "xfs_dinode.h" +#include "xfs_inode_item.h" +#include "xfs_inode.h" +#include "xfs_bmap.h" +#include "xfs_error.h" +#include "xfs_quota.h" +#include "xfs_refcache.h" +#include "xfs_utils.h" +#include "xfs_trans_space.h" +#include "xfs_da_btree.h" +#include "xfs_dir_leaf.h" + + +/* + * Given an array of up to 4 inode pointers, unlock the pointed to inodes. + * If there are fewer than 4 entries in the array, the empty entries will + * be at the end and will have NULL pointers in them. + */ +STATIC void +xfs_rename_unlock4( + xfs_inode_t **i_tab, + uint lock_mode) +{ + int i; + + xfs_iunlock(i_tab[0], lock_mode); + for (i = 1; i < 4; i++) { + if (i_tab[i] == NULL) { + break; + } + /* + * Watch out for duplicate entries in the table. + */ + if (i_tab[i] != i_tab[i-1]) { + xfs_iunlock(i_tab[i], lock_mode); + } + } +} + +#ifdef DEBUG +int xfs_rename_skip, xfs_rename_nskip; +#endif + +/* + * The following routine will acquire the locks required for a rename + * operation. The code understands the semantics of renames and will + * validate that name1 exists under dp1 & that name2 may or may not + * exist under dp2. + * + * We are renaming dp1/name1 to dp2/name2. + * + * Return ENOENT if dp1 does not exist, other lookup errors, or 0 for success. + */ +STATIC int +xfs_lock_for_rename( + xfs_inode_t *dp1, /* old (source) directory inode */ + xfs_inode_t *dp2, /* new (target) directory inode */ + vname_t *vname1,/* old entry name */ + vname_t *vname2,/* new entry name */ + xfs_inode_t **ipp1, /* inode of old entry */ + xfs_inode_t **ipp2, /* inode of new entry, if it + already exists, NULL otherwise. */ + xfs_inode_t **i_tab,/* array of inode returned, sorted */ + int *num_inodes) /* number of inodes in array */ +{ + xfs_inode_t *ip1, *ip2, *temp; + xfs_ino_t inum1, inum2; + int error; + int i, j; + uint lock_mode; + int diff_dirs = (dp1 != dp2); + + ip2 = NULL; + + /* + * First, find out the current inums of the entries so that we + * can determine the initial locking order. We'll have to + * sanity check stuff after all the locks have been acquired + * to see if we still have the right inodes, directories, etc. + */ + lock_mode = xfs_ilock_map_shared(dp1); + error = xfs_get_dir_entry(vname1, &ip1); + if (error) { + xfs_iunlock_map_shared(dp1, lock_mode); + return error; + } + + inum1 = ip1->i_ino; + + ASSERT(ip1); + ITRACE(ip1); + + /* + * Unlock dp1 and lock dp2 if they are different. + */ + + if (diff_dirs) { + xfs_iunlock_map_shared(dp1, lock_mode); + lock_mode = xfs_ilock_map_shared(dp2); + } + + error = xfs_dir_lookup_int(XFS_ITOBHV(dp2), lock_mode, + vname2, &inum2, &ip2); + if (error == ENOENT) { /* target does not need to exist. */ + inum2 = 0; + } else if (error) { + /* + * If dp2 and dp1 are the same, the next line unlocks dp1. + * Got it? + */ + xfs_iunlock_map_shared(dp2, lock_mode); + IRELE (ip1); + return error; + } else { + ITRACE(ip2); + } + + /* + * i_tab contains a list of pointers to inodes. We initialize + * the table here & we'll sort it. We will then use it to + * order the acquisition of the inode locks. + * + * Note that the table may contain duplicates. e.g., dp1 == dp2. + */ + i_tab[0] = dp1; + i_tab[1] = dp2; + i_tab[2] = ip1; + if (inum2 == 0) { + *num_inodes = 3; + i_tab[3] = NULL; + } else { + *num_inodes = 4; + i_tab[3] = ip2; + } + + /* + * Sort the elements via bubble sort. (Remember, there are at + * most 4 elements to sort, so this is adequate.) + */ + for (i=0; i < *num_inodes; i++) { + for (j=1; j < *num_inodes; j++) { + if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) { + temp = i_tab[j]; + i_tab[j] = i_tab[j-1]; + i_tab[j-1] = temp; + } + } + } + + /* + * We have dp2 locked. If it isn't first, unlock it. + * If it is first, tell xfs_lock_inodes so it can skip it + * when locking. if dp1 == dp2, xfs_lock_inodes will skip both + * since they are equal. xfs_lock_inodes needs all these inodes + * so that it can unlock and retry if there might be a dead-lock + * potential with the log. + */ + + if (i_tab[0] == dp2 && lock_mode == XFS_ILOCK_SHARED) { +#ifdef DEBUG + xfs_rename_skip++; +#endif + xfs_lock_inodes(i_tab, *num_inodes, 1, XFS_ILOCK_SHARED); + } else { +#ifdef DEBUG + xfs_rename_nskip++; +#endif + xfs_iunlock_map_shared(dp2, lock_mode); + xfs_lock_inodes(i_tab, *num_inodes, 0, XFS_ILOCK_SHARED); + } + + /* + * Set the return value. Null out any unused entries in i_tab. + */ + *ipp1 = *ipp2 = NULL; + for (i=0; i < *num_inodes; i++) { + if (i_tab[i]->i_ino == inum1) { + *ipp1 = i_tab[i]; + } + if (i_tab[i]->i_ino == inum2) { + *ipp2 = i_tab[i]; + } + } + for (;i < 4; i++) { + i_tab[i] = NULL; + } + return 0; +} + + +int rename_which_error_return = 0; + +/* + * xfs_rename + */ +int +xfs_rename( + bhv_desc_t *src_dir_bdp, + vname_t *src_vname, + vnode_t *target_dir_vp, + vname_t *target_vname, + cred_t *credp) +{ + xfs_trans_t *tp; + xfs_inode_t *src_dp, *target_dp, *src_ip, *target_ip; + xfs_mount_t *mp; + int new_parent; /* moving to a new dir */ + int src_is_directory; /* src_name is a directory */ + int error; + xfs_bmap_free_t free_list; + xfs_fsblock_t first_block; + int cancel_flags; + int committed; + xfs_inode_t *inodes[4]; + int target_ip_dropped = 0; /* dropped target_ip link? */ + vnode_t *src_dir_vp; + bhv_desc_t *target_dir_bdp; + int spaceres; + int target_link_zero = 0; + int num_inodes; + char *src_name = VNAME(src_vname); + char *target_name = VNAME(target_vname); + int src_namelen = VNAMELEN(src_vname); + int target_namelen = VNAMELEN(target_vname); + + src_dir_vp = BHV_TO_VNODE(src_dir_bdp); + vn_trace_entry(src_dir_vp, "xfs_rename", (inst_t *)__return_address); + vn_trace_entry(target_dir_vp, "xfs_rename", (inst_t *)__return_address); + + /* + * Find the XFS behavior descriptor for the target directory + * vnode since it was not handed to us. + */ + target_dir_bdp = vn_bhv_lookup_unlocked(VN_BHV_HEAD(target_dir_vp), + &xfs_vnodeops); + if (target_dir_bdp == NULL) { + return XFS_ERROR(EXDEV); + } + + src_dp = XFS_BHVTOI(src_dir_bdp); + target_dp = XFS_BHVTOI(target_dir_bdp); + mp = src_dp->i_mount; + + if (DM_EVENT_ENABLED(src_dir_vp->v_vfsp, src_dp, DM_EVENT_RENAME) || + DM_EVENT_ENABLED(target_dir_vp->v_vfsp, + target_dp, DM_EVENT_RENAME)) { + error = XFS_SEND_NAMESP(mp, DM_EVENT_RENAME, + src_dir_vp, DM_RIGHT_NULL, + target_dir_vp, DM_RIGHT_NULL, + src_name, target_name, + 0, 0, 0); + if (error) { + return error; + } + } + /* Return through std_return after this point. */ + + /* + * Lock all the participating inodes. Depending upon whether + * the target_name exists in the target directory, and + * whether the target directory is the same as the source + * directory, we can lock from 2 to 4 inodes. + * xfs_lock_for_rename() will return ENOENT if src_name + * does not exist in the source directory. + */ + tp = NULL; + error = xfs_lock_for_rename(src_dp, target_dp, src_vname, + target_vname, &src_ip, &target_ip, inodes, + &num_inodes); + + if (error) { + rename_which_error_return = __LINE__; + /* + * We have nothing locked, no inode references, and + * no transaction, so just get out. + */ + goto std_return; + } + + ASSERT(src_ip != NULL); + + if ((src_ip->i_d.di_mode & S_IFMT) == S_IFDIR) { + /* + * Check for link count overflow on target_dp + */ + if (target_ip == NULL && (src_dp != target_dp) && + target_dp->i_d.di_nlink >= XFS_MAXLINK) { + rename_which_error_return = __LINE__; + error = XFS_ERROR(EMLINK); + xfs_rename_unlock4(inodes, XFS_ILOCK_SHARED); + goto rele_return; + } + } + + new_parent = (src_dp != target_dp); + src_is_directory = ((src_ip->i_d.di_mode & S_IFMT) == S_IFDIR); + + /* + * Drop the locks on our inodes so that we can start the transaction. + */ + xfs_rename_unlock4(inodes, XFS_ILOCK_SHARED); + + XFS_BMAP_INIT(&free_list, &first_block); + tp = xfs_trans_alloc(mp, XFS_TRANS_RENAME); + cancel_flags = XFS_TRANS_RELEASE_LOG_RES; + spaceres = XFS_RENAME_SPACE_RES(mp, target_namelen); + error = xfs_trans_reserve(tp, spaceres, XFS_RENAME_LOG_RES(mp), 0, + XFS_TRANS_PERM_LOG_RES, XFS_RENAME_LOG_COUNT); + if (error == ENOSPC) { + spaceres = 0; + error = xfs_trans_reserve(tp, 0, XFS_RENAME_LOG_RES(mp), 0, + XFS_TRANS_PERM_LOG_RES, XFS_RENAME_LOG_COUNT); + } + if (error) { + rename_which_error_return = __LINE__; + xfs_trans_cancel(tp, 0); + goto rele_return; + } + + /* + * Attach the dquots to the inodes + */ + if ((error = XFS_QM_DQVOPRENAME(mp, inodes))) { + xfs_trans_cancel(tp, cancel_flags); + rename_which_error_return = __LINE__; + goto rele_return; + } + + /* + * Reacquire the inode locks we dropped above. + */ + xfs_lock_inodes(inodes, num_inodes, 0, XFS_ILOCK_EXCL); + + /* + * Join all the inodes to the transaction. From this point on, + * we can rely on either trans_commit or trans_cancel to unlock + * them. Note that we need to add a vnode reference to the + * directories since trans_commit & trans_cancel will decrement + * them when they unlock the inodes. Also, we need to be careful + * not to add an inode to the transaction more than once. + */ + VN_HOLD(src_dir_vp); + xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL); + if (new_parent) { + VN_HOLD(target_dir_vp); + xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL); + } + if ((src_ip != src_dp) && (src_ip != target_dp)) { + xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL); + } + if ((target_ip != NULL) && + (target_ip != src_ip) && + (target_ip != src_dp) && + (target_ip != target_dp)) { + xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL); + } + + /* + * Set up the target. + */ + if (target_ip == NULL) { + /* + * If there's no space reservation, check the entry will + * fit before actually inserting it. + */ + if (spaceres == 0 && + (error = XFS_DIR_CANENTER(mp, tp, target_dp, target_name, + target_namelen))) { + rename_which_error_return = __LINE__; + goto error_return; + } + /* + * If target does not exist and the rename crosses + * directories, adjust the target directory link count + * to account for the ".." reference from the new entry. + */ + error = XFS_DIR_CREATENAME(mp, tp, target_dp, target_name, + target_namelen, src_ip->i_ino, + &first_block, &free_list, spaceres); + if (error == ENOSPC) { + rename_which_error_return = __LINE__; + goto error_return; + } + if (error) { + rename_which_error_return = __LINE__; + goto abort_return; + } + xfs_ichgtime(target_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); + + if (new_parent && src_is_directory) { + error = xfs_bumplink(tp, target_dp); + if (error) { + rename_which_error_return = __LINE__; + goto abort_return; + } + } + } else { /* target_ip != NULL */ + + /* + * If target exists and it's a directory, check that both + * target and source are directories and that target can be + * destroyed, or that neither is a directory. + */ + if ((target_ip->i_d.di_mode & S_IFMT) == S_IFDIR) { + /* + * Make sure target dir is empty. + */ + if (!(XFS_DIR_ISEMPTY(target_ip->i_mount, target_ip)) || + (target_ip->i_d.di_nlink > 2)) { + error = XFS_ERROR(EEXIST); + rename_which_error_return = __LINE__; + goto error_return; + } + } + + /* + * Link the source inode under the target name. + * If the source inode is a directory and we are moving + * it across directories, its ".." entry will be + * inconsistent until we replace that down below. + * + * In case there is already an entry with the same + * name at the destination directory, remove it first. + */ + error = XFS_DIR_REPLACE(mp, tp, target_dp, target_name, + target_namelen, src_ip->i_ino, &first_block, + &free_list, spaceres); + if (error) { + rename_which_error_return = __LINE__; + goto abort_return; + } + xfs_ichgtime(target_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); + + /* + * Decrement the link count on the target since the target + * dir no longer points to it. + */ + error = xfs_droplink(tp, target_ip); + if (error) { + rename_which_error_return = __LINE__; + goto abort_return; + } + target_ip_dropped = 1; + + if (src_is_directory) { + /* + * Drop the link from the old "." entry. + */ + error = xfs_droplink(tp, target_ip); + if (error) { + rename_which_error_return = __LINE__; + goto abort_return; + } + } + + /* Do this test while we still hold the locks */ + target_link_zero = (target_ip)->i_d.di_nlink==0; + + } /* target_ip != NULL */ + + /* + * Remove the source. + */ + if (new_parent && src_is_directory) { + + /* + * Rewrite the ".." entry to point to the new + * directory. + */ + error = XFS_DIR_REPLACE(mp, tp, src_ip, "..", 2, + target_dp->i_ino, &first_block, + &free_list, spaceres); + ASSERT(error != EEXIST); + if (error) { + rename_which_error_return = __LINE__; + goto abort_return; + } + xfs_ichgtime(src_ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); + + } else { + /* + * We always want to hit the ctime on the source inode. + * We do it in the if clause above for the 'new_parent && + * src_is_directory' case, and here we get all the other + * cases. This isn't strictly required by the standards + * since the source inode isn't really being changed, + * but old unix file systems did it and some incremental + * backup programs won't work without it. + */ + xfs_ichgtime(src_ip, XFS_ICHGTIME_CHG); + } + + /* + * Adjust the link count on src_dp. This is necessary when + * renaming a directory, either within one parent when + * the target existed, or across two parent directories. + */ + if (src_is_directory && (new_parent || target_ip != NULL)) { + + /* + * Decrement link count on src_directory since the + * entry that's moved no longer points to it. + */ + error = xfs_droplink(tp, src_dp); + if (error) { + rename_which_error_return = __LINE__; + goto abort_return; + } + } + + error = XFS_DIR_REMOVENAME(mp, tp, src_dp, src_name, src_namelen, + src_ip->i_ino, &first_block, &free_list, spaceres); + if (error) { + rename_which_error_return = __LINE__; + goto abort_return; + } + xfs_ichgtime(src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); + + /* + * Update the generation counts on all the directory inodes + * that we're modifying. + */ + src_dp->i_gen++; + xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE); + + if (new_parent) { + target_dp->i_gen++; + xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE); + } + + /* + * If there was a target inode, take an extra reference on + * it here so that it doesn't go to xfs_inactive() from + * within the commit. + */ + if (target_ip != NULL) { + IHOLD(target_ip); + } + + /* + * If this is a synchronous mount, make sure that the + * rename transaction goes to disk before returning to + * the user. + */ + if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) { + xfs_trans_set_sync(tp); + } + + /* + * Take refs. for vop_link_removed calls below. No need to worry + * about directory refs. because the caller holds them. + * + * Do holds before the xfs_bmap_finish since it might rele them down + * to zero. + */ + + if (target_ip_dropped) + IHOLD(target_ip); + IHOLD(src_ip); + + error = xfs_bmap_finish(&tp, &free_list, first_block, &committed); + if (error) { + xfs_bmap_cancel(&free_list); + xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES | + XFS_TRANS_ABORT)); + if (target_ip != NULL) { + IRELE(target_ip); + } + if (target_ip_dropped) { + IRELE(target_ip); + } + IRELE(src_ip); + goto std_return; + } + + /* + * trans_commit will unlock src_ip, target_ip & decrement + * the vnode references. + */ + error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL); + if (target_ip != NULL) { + xfs_refcache_purge_ip(target_ip); + IRELE(target_ip); + } + /* + * Let interposed file systems know about removed links. + */ + if (target_ip_dropped) { + VOP_LINK_REMOVED(XFS_ITOV(target_ip), target_dir_vp, + target_link_zero); + IRELE(target_ip); + } + + FSC_NOTIFY_NAME_CHANGED(XFS_ITOV(src_ip)); + + IRELE(src_ip); + + /* Fall through to std_return with error = 0 or errno from + * xfs_trans_commit */ +std_return: + if (DM_EVENT_ENABLED(src_dir_vp->v_vfsp, src_dp, DM_EVENT_POSTRENAME) || + DM_EVENT_ENABLED(target_dir_vp->v_vfsp, + target_dp, DM_EVENT_POSTRENAME)) { + (void) XFS_SEND_NAMESP (mp, DM_EVENT_POSTRENAME, + src_dir_vp, DM_RIGHT_NULL, + target_dir_vp, DM_RIGHT_NULL, + src_name, target_name, + 0, error, 0); + } + return error; + + abort_return: + cancel_flags |= XFS_TRANS_ABORT; + /* FALLTHROUGH */ + error_return: + xfs_bmap_cancel(&free_list); + xfs_trans_cancel(tp, cancel_flags); + goto std_return; + + rele_return: + IRELE(src_ip); + if (target_ip != NULL) { + IRELE(target_ip); + } + goto std_return; +} |