xfs: Add support to RENAME_EXCHANGE flag

Adds a new function named xfs_cross_rename(), responsible for
handling requests from sys_renameat2() using RENAME_EXCHANGE flag.

Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This commit is contained in:
Carlos Maiolino 2014-12-24 08:51:42 +11:00 committed by Dave Chinner
parent dbe1b5ca26
commit d31a182545
3 changed files with 142 additions and 6 deletions

View File

@ -2655,6 +2655,124 @@ xfs_sort_for_rename(
}
}
/*
* xfs_cross_rename()
*
* responsible for handling RENAME_EXCHANGE flag in renameat2() sytemcall
*/
STATIC int
xfs_cross_rename(
struct xfs_trans *tp,
struct xfs_inode *dp1,
struct xfs_name *name1,
struct xfs_inode *ip1,
struct xfs_inode *dp2,
struct xfs_name *name2,
struct xfs_inode *ip2,
struct xfs_bmap_free *free_list,
xfs_fsblock_t *first_block,
int spaceres)
{
int error = 0;
int ip1_flags = 0;
int ip2_flags = 0;
int dp2_flags = 0;
/* Swap inode number for dirent in first parent */
error = xfs_dir_replace(tp, dp1, name1,
ip2->i_ino,
first_block, free_list, spaceres);
if (error)
goto out;
/* Swap inode number for dirent in second parent */
error = xfs_dir_replace(tp, dp2, name2,
ip1->i_ino,
first_block, free_list, spaceres);
if (error)
goto out;
/*
* If we're renaming one or more directories across different parents,
* update the respective ".." entries (and link counts) to match the new
* parents.
*/
if (dp1 != dp2) {
dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
if (S_ISDIR(ip2->i_d.di_mode)) {
error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot,
dp1->i_ino, first_block,
free_list, spaceres);
if (error)
goto out;
/* transfer ip2 ".." reference to dp1 */
if (!S_ISDIR(ip1->i_d.di_mode)) {
error = xfs_droplink(tp, dp2);
if (error)
goto out;
error = xfs_bumplink(tp, dp1);
if (error)
goto out;
}
/*
* Although ip1 isn't changed here, userspace needs
* to be warned about the change, so that applications
* relying on it (like backup ones), will properly
* notify the change
*/
ip1_flags |= XFS_ICHGTIME_CHG;
ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
}
if (S_ISDIR(ip1->i_d.di_mode)) {
error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot,
dp2->i_ino, first_block,
free_list, spaceres);
if (error)
goto out;
/* transfer ip1 ".." reference to dp2 */
if (!S_ISDIR(ip2->i_d.di_mode)) {
error = xfs_droplink(tp, dp1);
if (error)
goto out;
error = xfs_bumplink(tp, dp2);
if (error)
goto out;
}
/*
* Although ip2 isn't changed here, userspace needs
* to be warned about the change, so that applications
* relying on it (like backup ones), will properly
* notify the change
*/
ip1_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
ip2_flags |= XFS_ICHGTIME_CHG;
}
}
if (ip1_flags) {
xfs_trans_ichgtime(tp, ip1, ip1_flags);
xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE);
}
if (ip2_flags) {
xfs_trans_ichgtime(tp, ip2, ip2_flags);
xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE);
}
if (dp2_flags) {
xfs_trans_ichgtime(tp, dp2, dp2_flags);
xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE);
}
xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE);
out:
return error;
}
/*
* xfs_rename
*/
@ -2665,7 +2783,8 @@ xfs_rename(
xfs_inode_t *src_ip,
xfs_inode_t *target_dp,
struct xfs_name *target_name,
xfs_inode_t *target_ip)
xfs_inode_t *target_ip,
unsigned int flags)
{
xfs_trans_t *tp = NULL;
xfs_mount_t *mp = src_dp->i_mount;
@ -2742,6 +2861,18 @@ xfs_rename(
goto error_return;
}
/*
* Handle RENAME_EXCHANGE flags
*/
if (flags & RENAME_EXCHANGE) {
error = xfs_cross_rename(tp, src_dp, src_name, src_ip,
target_dp, target_name, target_ip,
&free_list, &first_block, spaceres);
if (error)
goto abort_return;
goto finish_rename;
}
/*
* Set up the target.
*/
@ -2881,6 +3012,7 @@ xfs_rename(
if (new_parent)
xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
finish_rename:
/*
* If this is a synchronous mount, make sure that the
* rename transaction goes to disk before returning to

View File

@ -338,7 +338,7 @@ int xfs_link(struct xfs_inode *tdp, struct xfs_inode *sip,
int xfs_rename(struct xfs_inode *src_dp, struct xfs_name *src_name,
struct xfs_inode *src_ip, struct xfs_inode *target_dp,
struct xfs_name *target_name,
struct xfs_inode *target_ip);
struct xfs_inode *target_ip, unsigned int flags);
void xfs_ilock(xfs_inode_t *, uint);
int xfs_ilock_nowait(xfs_inode_t *, uint);

View File

@ -384,19 +384,23 @@ xfs_vn_rename(
unsigned int flags)
{
struct inode *new_inode = ndentry->d_inode;
int omode = 0;
struct xfs_name oname;
struct xfs_name nname;
/* XFS does not support RENAME_EXCHANGE yet */
if (flags & ~RENAME_NOREPLACE)
if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
return -EINVAL;
xfs_dentry_to_name(&oname, odentry, 0);
/* if we are exchanging files, we need to set i_mode of both files */
if (flags & RENAME_EXCHANGE)
omode = ndentry->d_inode->i_mode;
xfs_dentry_to_name(&oname, odentry, omode);
xfs_dentry_to_name(&nname, ndentry, odentry->d_inode->i_mode);
return xfs_rename(XFS_I(odir), &oname, XFS_I(odentry->d_inode),
XFS_I(ndir), &nname,
new_inode ? XFS_I(new_inode) : NULL);
new_inode ? XFS_I(new_inode) : NULL, flags);
}
/*