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/*
* Copyright (c) 2000 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>
/*
* 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);
}
}
}
/*
* Compare the i_gen fields of the inodes pointed to in the array of
* inode pointers to the gen values stored at the same offset in the
* array of generation counts. Return 0 if they are the same and 1
* if they are different.
*
* There are a maximum of 4 entries in the array. If there are
* fewer than that, the first empty entry will have a NULL pointer.
*/
STATIC int
xfs_rename_compare_gencounts(
xfs_inode_t **i_tab,
int *i_gencounts)
{
int i;
int compare;
compare = 0;
for (i = 0; i < 4; i++) {
if (i_tab[i] == NULL) {
break;
}
if (i_tab[i]->i_gen != i_gencounts[i]) {
compare = 1;
break;
}
}
return compare;
}
#ifdef DEBUG
int xfs_rename_check0, xfs_rename_check1, xfs_rename_check2;
#endif
/*
* The following routine needs all inodes locked before being called.
* It checks to see if the inums and names are still valid as passed in.
*
* For now, only check if dp1 == dp2.
*
* Return 1 if still OK.
* Return 0 otherwize.
*/
STATIC int
xfs_rename_check_ok(
xfs_inode_t *dp1, /* old (source) directory inode */
xfs_inode_t *dp2, /* new (target) directory inode */
char *name1, /* old entry name */
char *name2, /* new entry name */
xfs_inode_t *ip1, /* inode of old entry */
xfs_inode_t *ip2) /* inode of new entry, if it
already existed, NULL otherwise. */
{
xfs_ino_t inum1, inum2;
int error, diffdirs;
ASSERT(dp1);
ASSERT(dp2);
ASSERT(ip1);
ASSERT((dp1->i_d.di_mode & IFMT) == IFDIR);
ASSERT((dp2->i_d.di_mode & IFMT) == IFDIR);
diffdirs = (dp1 != dp2);
#ifdef DEBUG
xfs_rename_check0++;
#endif
if (dp1->i_d.di_nlink == 0 || (diffdirs && (dp2->i_d.di_nlink == 0))) {
return(0);
}
if ((ip1->i_d.di_mode & IFMT) == IFDIR) {
return(0);
}
if (ip2 && ((ip2->i_d.di_mode & IFMT) == IFDIR)) {
return(0);
}
/*
* Get the inum for name1 and compare to the value in ip1.
* Need to worry about dead-lock here since we have all the inode
* locks.
*/
error = xfs_dir_lookup_int(NULL, XFS_ITOBHV(dp1), DLF_NODNLC,
name1, NULL, &inum1, NULL, NULL);
if (error) { /* name1 must be gone or .... */
return(0);
}
if (inum1 != ip1->i_ino) { /* name1 is now a different inode */
return(0);
}
#ifdef DEBUG
xfs_rename_check1++;
#endif
/*
* Get the inum for name2 and compare to the value in ip2.
* Need to worry about dead-lock here since we have all the inode
* locks.
*/
error = xfs_dir_lookup_int(NULL, XFS_ITOBHV(dp2), DLF_NODNLC,
name2, NULL, &inum2, NULL, NULL);
/*
* If we have an unsuccessful lookup and ip2 was passed in, the dest is
* now gone so we need to start over.
* If we have a successful lookup and ip2 was not found before,
* we need to start over, too.
*/
if ((error && ip2) || (!error && !ip2)) {
return(0);
}
if (ip2 && (inum2 != ip2->i_ino)) { /* name2 is now a different inode */
return(0);
}
#ifdef DEBUG
xfs_rename_check2++;
#endif
return(1);
}
#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.
* Return EAGAIN if the caller needs to try again.
*/
STATIC int
xfs_lock_for_rename(
xfs_inode_t *dp1, /* old (source) directory inode */
xfs_inode_t *dp2, /* new (target) directory inode */
char *name1, /* old entry name */
char *name2, /* 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 */
int *i_gencounts) /* array of inode gen counts */
{
xfs_inode_t *ip1, *ip2, *temp;
xfs_ino_t inum1, inum2;
unsigned long dir_gen1, dir_gen2;
int error;
int i, j;
uint lock_mode;
uint dir_unlocked;
uint lookup_flags;
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);
/*
* We don't want to do lookups in unlinked directories.
*/
if (dp1->i_d.di_nlink == 0) {
xfs_iunlock_map_shared(dp1, lock_mode);
return XFS_ERROR(ENOENT);
}
lookup_flags = DLF_IGET;
if (lock_mode == XFS_ILOCK_SHARED) {
lookup_flags |= DLF_LOCK_SHARED;
}
error = xfs_dir_lookup_int(NULL, XFS_ITOBHV(dp1), lookup_flags,
name1, NULL, &inum1, &ip1, &dir_unlocked);
/*
* Save the current generation so that we can detect if it's
* modified between when we drop the lock & reacquire it down
* below. We only need to do this for the src directory since
* the target entry does not need to exist yet.
*/
dir_gen1 = dp1->i_gen;
if (error) {
xfs_iunlock_map_shared(dp1, lock_mode);
return error;
}
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);
/*
* We don't want to do lookups in unlinked directories.
*/
if (dp2->i_d.di_nlink == 0) {
xfs_iunlock_map_shared(dp2, lock_mode);
return XFS_ERROR(ENOENT);
}
}
lookup_flags = DLF_IGET;
if (lock_mode == XFS_ILOCK_SHARED) {
lookup_flags |= DLF_LOCK_SHARED;
}
error = xfs_dir_lookup_int(NULL, XFS_ITOBHV(dp2), lookup_flags,
name2, NULL, &inum2, &ip2, &dir_unlocked);
dir_gen2 = dp2->i_gen;
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);
}
/*
* See if either of the directories was modified during the
* interval between when the locks were released and when
* they were reacquired.
*/
if (dp1->i_gen != dir_gen1 || (diff_dirs && (dp2->i_gen != dir_gen2))) {
/*
* Someone else may have linked in a new inode
* with the same name. If so, we'll need to
* release our locks & go through the whole
* thing again.
*/
xfs_iunlock(i_tab[0], XFS_ILOCK_SHARED);
for (i=1; i < *num_inodes; i++) {
if (i_tab[i] != i_tab[i-1])
xfs_iunlock(i_tab[i], XFS_ILOCK_SHARED);
}
if (*num_inodes == 4) {
IRELE (ip2);
}
IRELE (ip1);
return XFS_ERROR(EAGAIN);
}
/*
* Set the return value. Return the gen counts of the inodes in
* i_tab in i_gencounts. 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];
}
i_gencounts[i] = i_tab[i]->i_gen;
}
for (;i < 4; i++) {
i_tab[i] = NULL;
}
return 0;
}
int rename_which_error_return = 0;
/*
* Do all the mundane error checking for xfs_rename(). The code
* assumes that all of the non-NULL inodes have already been locked.
*/
STATIC int
xfs_rename_error_checks(
xfs_inode_t *src_dp,
xfs_inode_t *target_dp,
xfs_inode_t *src_ip,
xfs_inode_t *target_ip,
char *src_name,
char *target_name,
cred_t *credp,
int *status)
{
int src_is_directory;
int error;
*status = 0;
error = 0;
/*
* If the target directory has been removed, we can't create any
* more files in it. We don't need to check the source dir,
* because it was checked in xfs_lock_for_rename() while looking
* for the source inode. If it had been removed the source
* dir's gen count would have been bumped removing the last entry
* and then we'd have noticed that its link count had gone to zero.
*/
if (target_dp->i_d.di_nlink == 0) {
error = XFS_ERROR(ENOENT);
*status = __LINE__;
goto error_return;
}
#if 0
if (error = xfs_iaccess(src_dp, IEXEC | IWRITE, credp)) {
*status = __LINE__;
goto error_return;
}
if (error = xfs_stickytest(src_dp, src_ip, credp)) {
*status = __LINE__;
goto error_return;
}
if (target_dp && (src_dp != target_dp)) {
if (error = xfs_iaccess(target_dp, IEXEC | IWRITE, credp)) {
*status = __LINE__;
goto error_return;
}
if ((target_ip != NULL) &&
(error = xfs_stickytest(target_dp, target_ip, credp))) {
*status = __LINE__;
goto error_return;
}
} else {
if ((target_ip != NULL) &&
(error = xfs_stickytest(src_dp, target_ip, credp))) {
*status = __LINE__;
goto error_return;
}
}
#endif
if ((src_ip == src_dp) || (target_ip == target_dp)) {
error = XFS_ERROR(EINVAL);
*status = __LINE__;
goto error_return;
}
/* Do some generic error tests now that we have the lock */
if ((error = xfs_pre_rename(XFS_ITOV(src_ip)))) {
error = XFS_ERROR(error);
*status = __LINE__;
goto error_return;
}
/*
* Source and target are identical.
*/
if (src_ip == target_ip) {
/*
* There is no error in this case, but we want to get
* out anyway. Set error to 0 so that no error will
* be returned, but set *status so that the caller
* will know that it should give up on the rename.
*/
error = 0;
*status = __LINE__;
goto error_return;
}
/*
* Directory renames require special checks.
*/
src_is_directory = ((src_ip->i_d.di_mode & IFMT) == IFDIR);
if (src_is_directory) {
ASSERT(src_ip->i_d.di_nlink >= 2);
/*
* Check for link count overflow on target_dp
*/
if (target_ip == NULL && (src_dp != target_dp) &&
target_dp->i_d.di_nlink >= XFS_MAXLINK) {
error = XFS_ERROR(EMLINK);
*status = __LINE__;
goto error_return;
}
/*
* Cannot rename ".."
*/
if ((src_name[0] == '.') && (src_name[1] == '.') &&
(src_name[2] == '\0')) {
error = XFS_ERROR(EINVAL);
*status = __LINE__;
goto error_return;
}
if ((target_name[0] == '.') && (target_name[1] == '.') &&
(target_name[2] == '\0')) {
error = XFS_ERROR(EINVAL);
*status = __LINE__;
goto error_return;
}
}
error_return:
return error;
}
/*
* Perform error checking on the target inode after the ancestor check
* has been done in xfs_rename().
*/
STATIC int
xfs_rename_target_checks(
xfs_inode_t *target_ip,
int src_is_directory)
{
int error;
error = 0;
/*
* 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 & IFMT) == IFDIR) {
/*
* Make sure src is a directory.
*/
if (!src_is_directory) {
error = XFS_ERROR(EISDIR);
rename_which_error_return = __LINE__;
goto error_return;
}
/*
* 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;
}
if ((error = xfs_pre_rmdir(XFS_ITOV(target_ip)))) {
error = XFS_ERROR(error);
rename_which_error_return = __LINE__;
goto error_return;
}
} else {
if ((error = xfs_pre_remove(XFS_ITOV(target_ip)))) {
error = XFS_ERROR(error);
rename_which_error_return = __LINE__;
goto error_return;
}
if (src_is_directory) {
error = XFS_ERROR(ENOTDIR);
rename_which_error_return = __LINE__;
goto error_return;
}
}
error_return:
return error;
}
#ifdef DEBUG
int xfs_rename_agains;
int xfs_renames;
int xfs_rename_tries;
int xfs_rename_max;
int xfs_rename_big;
int xfs_rename_retries0;
int xfs_rename_retries1;
int xfs_rename_retries2;
int xfs_rename_retries3;
#endif
/*
* xfs_rename
*/
int
xfs_rename(
bhv_desc_t *src_dir_bdp,
char *src_name,
vnode_t *target_dir_vp,
char *target_name,
pathname_t *target_pnp,
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;
int status;
xfs_inode_t *inodes[4];
int gencounts[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;
int src_namelen;
int target_namelen;
#ifdef DEBUG
int retries;
xfs_renames++;
#endif
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_namelen = strlen(src_name);
if (src_namelen >= MAXNAMELEN)
return XFS_ERROR(ENAMETOOLONG);
target_namelen = strlen(target_name);
if (target_namelen >= MAXNAMELEN)
return XFS_ERROR(ENAMETOOLONG);
src_dp = XFS_BHVTOI(src_dir_bdp);
target_dp = XFS_BHVTOI(target_dir_bdp);
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 = dm_send_namesp_event(DM_EVENT_RENAME,
src_dir_bdp, DM_RIGHT_NULL,
target_dir_bdp, DM_RIGHT_NULL,
src_name, target_name,
0, 0, 0);
if (error) {
return error;
}
}
/* Return through std_return after this point. */
#ifdef DEBUG
retries = 0;
#endif
start_over:
/*
* 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;
do {
error = xfs_lock_for_rename(src_dp, target_dp, src_name,
target_name, &src_ip, &target_ip, inodes,
&num_inodes, gencounts);
#ifdef DEBUG
if (error == EAGAIN) xfs_rename_agains++;
#endif
} while (error == EAGAIN);
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);
error = xfs_rename_error_checks(src_dp, target_dp, src_ip,
target_ip, src_name, target_name, credp, &status);
if (error || status) {
rename_which_error_return = status;
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 & IFMT) == IFDIR);
/*
* Drop the locks on our inodes so that we can do the ancestor
* check if necessary and start the transaction. We have already
* saved the i_gen fields of each of the inode in the gencounts
* array when we called xfs_lock_for_rename().
*/
xfs_rename_unlock4(inodes, XFS_ILOCK_SHARED);
XFS_BMAP_INIT(&free_list, &first_block);
mp = src_dp->i_mount;
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 (XFS_IS_QUOTA_ON(mp)) {
if ((error = xfs_qm_vop_rename_dqattach(inodes))) {
xfs_trans_cancel(tp, cancel_flags);
rename_which_error_return = __LINE__;
goto rele_return;
}
}
/*
* Reacquire the inode locks we dropped above. Then check the
* generation counts on the inodes. If any of them have changed,
* we cancel the transaction and start over from the top.
*/
xfs_lock_inodes(inodes, num_inodes, 0, XFS_ILOCK_EXCL);
if (xfs_rename_compare_gencounts(inodes, gencounts)) {
/*
* If the ancestors don't need to be checked, see if
* the gencount change indicates that we really need
* to start over.
*/
if(!xfs_rename_check_ok(src_dp, target_dp, src_name,
target_name, src_ip, target_ip)) {
xfs_trans_cancel(tp, cancel_flags);
xfs_rename_unlock4(inodes, XFS_ILOCK_EXCL);
IRELE(src_ip);
if (target_ip != NULL) {
IRELE(target_ip);
}
#ifdef DEBUG
xfs_rename_tries++;
retries++;
if (retries > xfs_rename_max)
xfs_rename_max = retries;
if (retries < 5) xfs_rename_retries0++;
else if (retries < 100) xfs_rename_retries1++;
else xfs_rename_retries2++;
if (retries > 100000) {
xfs_rename_big++;
}
#endif
goto start_over;
#ifdef DEBUG
} else {
xfs_rename_retries3++;
#endif
}
}
/*
* 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);
}
/*
* We should be in the same file system.
*/
ASSERT(src_dp->i_mount == target_dp->i_mount);
/*
* We have to redo all of the checks we did above, because we've
* unlocked all of the inodes in the interim.
*/
error = xfs_rename_error_checks(src_dp, target_dp, src_ip,
target_ip, src_name, target_name, credp, &status);
if (error || status) {
rename_which_error_return = status;
goto error_return;
}
/*
* 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 */
error = xfs_rename_target_checks(target_ip,
src_is_directory);
if (error) {
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_pnp != NULL) ? target_pnp->pn_complen :
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;
/* Do this test while we still hold the locks */
target_link_zero = (target_ip)->i_d.di_nlink==0;
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;
}
}
} /* 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_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) dm_send_namesp_event(DM_EVENT_POSTRENAME,
src_dir_bdp, DM_RIGHT_NULL,
target_dir_bdp, 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;
}
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