xfs: avoid ilock games in the quota scrubber

Refactor the quota scrubber to take the quotaofflock and grab the quota
inode in the setup function so that we can treat quota in the same
"scrub in the context of this inode" (i.e. sc->ip) manner as we treat
any other inode.  We do have to drop the quota inode's ILOCK_EXCL to use
dqiterate, but since dquots have their own individual locks the ILOCK
wasn't helping us anyway.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
This commit is contained in:
Darrick J. Wong 2018-05-09 10:02:00 -07:00
parent 554ba96540
commit eb41c93fef
3 changed files with 30 additions and 28 deletions

View file

@ -66,12 +66,24 @@ xfs_scrub_setup_quota(
struct xfs_inode *ip)
{
uint dqtype;
int error;
if (!XFS_IS_QUOTA_RUNNING(sc->mp) || !XFS_IS_QUOTA_ON(sc->mp))
return -ENOENT;
dqtype = xfs_scrub_quota_to_dqtype(sc);
if (dqtype == 0)
return -EINVAL;
sc->has_quotaofflock = true;
mutex_lock(&sc->mp->m_quotainfo->qi_quotaofflock);
if (!xfs_this_quota_on(sc->mp, dqtype))
return -ENOENT;
error = xfs_scrub_setup_fs(sc, ip);
if (error)
return error;
sc->ip = xfs_quota_inode(sc->mp, dqtype);
xfs_ilock(sc->ip, XFS_ILOCK_EXCL);
sc->ilock_flags = XFS_ILOCK_EXCL;
return 0;
}
@ -202,7 +214,6 @@ xfs_scrub_quota(
struct xfs_bmbt_irec irec = { 0 };
struct xfs_scrub_quota_info sqi;
struct xfs_mount *mp = sc->mp;
struct xfs_inode *ip;
struct xfs_quotainfo *qi = mp->m_quotainfo;
xfs_fileoff_t max_dqid_off;
xfs_fileoff_t off = 0;
@ -210,25 +221,12 @@ xfs_scrub_quota(
int nimaps;
int error = 0;
if (!XFS_IS_QUOTA_RUNNING(mp) || !XFS_IS_QUOTA_ON(mp))
return -ENOENT;
mutex_lock(&qi->qi_quotaofflock);
dqtype = xfs_scrub_quota_to_dqtype(sc);
if (!xfs_this_quota_on(sc->mp, dqtype)) {
error = -ENOENT;
goto out_unlock_quota;
}
/* Attach to the quota inode and set sc->ip so that reporting works. */
ip = xfs_quota_inode(sc->mp, dqtype);
sc->ip = ip;
/* Look for problem extents. */
xfs_ilock(ip, XFS_ILOCK_EXCL);
if (ip->i_d.di_flags & XFS_DIFLAG_REALTIME) {
if (sc->ip->i_d.di_flags & XFS_DIFLAG_REALTIME) {
xfs_scrub_ino_set_corrupt(sc, sc->ip->i_ino);
goto out_unlock_inode;
goto out;
}
max_dqid_off = ((xfs_dqid_t)-1) / qi->qi_dqperchunk;
while (1) {
@ -237,11 +235,11 @@ xfs_scrub_quota(
off = irec.br_startoff + irec.br_blockcount;
nimaps = 1;
error = xfs_bmapi_read(ip, off, -1, &irec, &nimaps,
error = xfs_bmapi_read(sc->ip, off, -1, &irec, &nimaps,
XFS_BMAPI_ENTIRE);
if (!xfs_scrub_fblock_process_error(sc, XFS_DATA_FORK, off,
&error))
goto out_unlock_inode;
goto out;
if (!nimaps)
break;
if (irec.br_startblock == HOLESTARTBLOCK)
@ -267,26 +265,25 @@ xfs_scrub_quota(
irec.br_startoff + irec.br_blockcount > max_dqid_off + 1)
xfs_scrub_fblock_set_corrupt(sc, XFS_DATA_FORK, off);
}
xfs_iunlock(ip, XFS_ILOCK_EXCL);
if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
goto out;
/* Check all the quota items. */
/*
* Check all the quota items. Now that we've checked the quota inode
* data fork we have to drop ILOCK_EXCL to use the regular dquot
* functions.
*/
xfs_iunlock(sc->ip, sc->ilock_flags);
sc->ilock_flags = 0;
sqi.sc = sc;
sqi.last_id = 0;
error = xfs_qm_dqiterate(mp, dqtype, xfs_scrub_quota_item, &sqi);
sc->ilock_flags = XFS_ILOCK_EXCL;
xfs_ilock(sc->ip, sc->ilock_flags);
if (!xfs_scrub_fblock_process_error(sc, XFS_DATA_FORK,
sqi.last_id * qi->qi_dqperchunk, &error))
goto out;
out:
/* We set sc->ip earlier, so make sure we clear it now. */
sc->ip = NULL;
out_unlock_quota:
mutex_unlock(&qi->qi_quotaofflock);
return error;
out_unlock_inode:
xfs_iunlock(ip, XFS_ILOCK_EXCL);
goto out;
}

View file

@ -42,6 +42,8 @@
#include "xfs_refcount_btree.h"
#include "xfs_rmap.h"
#include "xfs_rmap_btree.h"
#include "xfs_quota.h"
#include "xfs_qm.h"
#include "scrub/xfs_scrub.h"
#include "scrub/scrub.h"
#include "scrub/common.h"
@ -166,6 +168,8 @@ xfs_scrub_teardown(
iput(VFS_I(sc->ip));
sc->ip = NULL;
}
if (sc->has_quotaofflock)
mutex_unlock(&sc->mp->m_quotainfo->qi_quotaofflock);
if (sc->buf) {
kmem_free(sc->buf);
sc->buf = NULL;

View file

@ -73,6 +73,7 @@ struct xfs_scrub_context {
void *buf;
uint ilock_flags;
bool try_harder;
bool has_quotaofflock;
/* State tracking for single-AG operations. */
struct xfs_scrub_ag sa;