From b84a3a96751f93071c1863f2962273973c8b8f5e Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 14 Mar 2012 11:53:34 -0500 Subject: xfs: remove the per-filesystem list of dquots Instead of keeping a separate per-filesystem list of dquots we can walk the radix tree for the two places where we need to iterate all quota structures. Reviewed-by: Dave Chinner Signed-off-by: Christoph Hellwig Signed-off-by: Ben Myers --- fs/xfs/xfs_qm.c | 415 ++++++++++++++++++++++++++++++-------------------------- 1 file changed, 219 insertions(+), 196 deletions(-) (limited to 'fs/xfs/xfs_qm.c') diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c index bb884e701cd9..2f92d3b0d8a8 100644 --- a/fs/xfs/xfs_qm.c +++ b/fs/xfs/xfs_qm.c @@ -168,6 +168,187 @@ xfs_qm_rele_quotafs_ref( mutex_unlock(&xfs_Gqm_lock); } +/* + * We use the batch lookup interface to iterate over the dquots as it + * currently is the only interface into the radix tree code that allows + * fuzzy lookups instead of exact matches. Holding the lock over multiple + * operations is fine as all callers are used either during mount/umount + * or quotaoff. + */ +#define XFS_DQ_LOOKUP_BATCH 32 + +STATIC int +xfs_qm_dquot_walk( + struct xfs_mount *mp, + int type, + int (*execute)(struct xfs_dquot *dqp)) +{ + struct xfs_quotainfo *qi = mp->m_quotainfo; + struct radix_tree_root *tree = XFS_DQUOT_TREE(qi, type); + uint32_t next_index; + int last_error = 0; + int skipped; + int nr_found; + +restart: + skipped = 0; + next_index = 0; + nr_found = 0; + + while (1) { + struct xfs_dquot *batch[XFS_DQ_LOOKUP_BATCH]; + int error = 0; + int i; + + mutex_lock(&qi->qi_tree_lock); + nr_found = radix_tree_gang_lookup(tree, (void **)batch, + next_index, XFS_DQ_LOOKUP_BATCH); + if (!nr_found) { + mutex_unlock(&qi->qi_tree_lock); + break; + } + + for (i = 0; i < nr_found; i++) { + struct xfs_dquot *dqp = batch[i]; + + next_index = be32_to_cpu(dqp->q_core.d_id) + 1; + + error = execute(batch[i]); + if (error == EAGAIN) { + skipped++; + continue; + } + if (error && last_error != EFSCORRUPTED) + last_error = error; + } + + mutex_unlock(&qi->qi_tree_lock); + + /* bail out if the filesystem is corrupted. */ + if (last_error == EFSCORRUPTED) { + skipped = 0; + break; + } + } + + if (skipped) { + delay(1); + goto restart; + } + + return last_error; +} + + +/* + * Purge a dquot from all tracking data structures and free it. + */ +STATIC int +xfs_qm_dqpurge( + struct xfs_dquot *dqp) +{ + struct xfs_mount *mp = dqp->q_mount; + struct xfs_quotainfo *qi = mp->m_quotainfo; + struct xfs_dquot *gdqp = NULL; + + xfs_dqlock(dqp); + if ((dqp->dq_flags & XFS_DQ_FREEING) || dqp->q_nrefs != 0) { + xfs_dqunlock(dqp); + return EAGAIN; + } + + /* + * If this quota has a group hint attached, prepare for releasing it + * now. + */ + gdqp = dqp->q_gdquot; + if (gdqp) { + xfs_dqlock(gdqp); + dqp->q_gdquot = NULL; + } + + dqp->dq_flags |= XFS_DQ_FREEING; + + /* + * If we're turning off quotas, we have to make sure that, for + * example, we don't delete quota disk blocks while dquots are + * in the process of getting written to those disk blocks. + * This dquot might well be on AIL, and we can't leave it there + * if we're turning off quotas. Basically, we need this flush + * lock, and are willing to block on it. + */ + if (!xfs_dqflock_nowait(dqp)) { + /* + * Block on the flush lock after nudging dquot buffer, + * if it is incore. + */ + xfs_dqflock_pushbuf_wait(dqp); + } + + /* + * If we are turning this type of quotas off, we don't care + * about the dirty metadata sitting in this dquot. OTOH, if + * we're unmounting, we do care, so we flush it and wait. + */ + if (XFS_DQ_IS_DIRTY(dqp)) { + int error; + + /* + * We don't care about getting disk errors here. We need + * to purge this dquot anyway, so we go ahead regardless. + */ + error = xfs_qm_dqflush(dqp, SYNC_WAIT); + if (error) + xfs_warn(mp, "%s: dquot %p flush failed", + __func__, dqp); + xfs_dqflock(dqp); + } + + ASSERT(atomic_read(&dqp->q_pincount) == 0); + ASSERT(XFS_FORCED_SHUTDOWN(mp) || + !(dqp->q_logitem.qli_item.li_flags & XFS_LI_IN_AIL)); + + xfs_dqfunlock(dqp); + xfs_dqunlock(dqp); + + radix_tree_delete(XFS_DQUOT_TREE(qi, dqp->q_core.d_flags), + be32_to_cpu(dqp->q_core.d_id)); + qi->qi_dquots--; + + /* + * We move dquots to the freelist as soon as their reference count + * hits zero, so it really should be on the freelist here. + */ + mutex_lock(&qi->qi_lru_lock); + ASSERT(!list_empty(&dqp->q_lru)); + list_del_init(&dqp->q_lru); + qi->qi_lru_count--; + XFS_STATS_DEC(xs_qm_dquot_unused); + mutex_unlock(&qi->qi_lru_lock); + + xfs_qm_dqdestroy(dqp); + + if (gdqp) + xfs_qm_dqput(gdqp); + return 0; +} + +/* + * Purge the dquot cache. + */ +void +xfs_qm_dqpurge_all( + struct xfs_mount *mp, + uint flags) +{ + if (flags & XFS_QMOPT_UQUOTA) + xfs_qm_dquot_walk(mp, XFS_DQ_USER, xfs_qm_dqpurge); + if (flags & XFS_QMOPT_GQUOTA) + xfs_qm_dquot_walk(mp, XFS_DQ_GROUP, xfs_qm_dqpurge); + if (flags & XFS_QMOPT_PQUOTA) + xfs_qm_dquot_walk(mp, XFS_DQ_PROJ, xfs_qm_dqpurge); +} + /* * Just destroy the quotainfo structure. */ @@ -306,175 +487,6 @@ xfs_qm_unmount_quotas( } } -/* - * Flush all dquots of the given file system to disk. The dquots are - * _not_ purged from memory here, just their data written to disk. - */ -STATIC int -xfs_qm_dqflush_all( - struct xfs_mount *mp) -{ - struct xfs_quotainfo *q = mp->m_quotainfo; - int recl; - struct xfs_dquot *dqp; - int error; - - if (!q) - return 0; -again: - mutex_lock(&q->qi_dqlist_lock); - list_for_each_entry(dqp, &q->qi_dqlist, q_mplist) { - xfs_dqlock(dqp); - if ((dqp->dq_flags & XFS_DQ_FREEING) || - !XFS_DQ_IS_DIRTY(dqp)) { - xfs_dqunlock(dqp); - continue; - } - - /* XXX a sentinel would be better */ - recl = q->qi_dqreclaims; - if (!xfs_dqflock_nowait(dqp)) { - /* - * If we can't grab the flush lock then check - * to see if the dquot has been flushed delayed - * write. If so, grab its buffer and send it - * out immediately. We'll be able to acquire - * the flush lock when the I/O completes. - */ - xfs_dqflock_pushbuf_wait(dqp); - } - /* - * Let go of the mplist lock. We don't want to hold it - * across a disk write. - */ - mutex_unlock(&q->qi_dqlist_lock); - error = xfs_qm_dqflush(dqp, 0); - xfs_dqunlock(dqp); - if (error) - return error; - - mutex_lock(&q->qi_dqlist_lock); - if (recl != q->qi_dqreclaims) { - mutex_unlock(&q->qi_dqlist_lock); - /* XXX restart limit */ - goto again; - } - } - - mutex_unlock(&q->qi_dqlist_lock); - /* return ! busy */ - return 0; -} - -/* - * Release the group dquot pointers the user dquots may be - * carrying around as a hint. mplist is locked on entry and exit. - */ -STATIC void -xfs_qm_detach_gdquots( - struct xfs_mount *mp) -{ - struct xfs_quotainfo *q = mp->m_quotainfo; - struct xfs_dquot *dqp, *gdqp; - - again: - ASSERT(mutex_is_locked(&q->qi_dqlist_lock)); - list_for_each_entry(dqp, &q->qi_dqlist, q_mplist) { - xfs_dqlock(dqp); - if (dqp->dq_flags & XFS_DQ_FREEING) { - xfs_dqunlock(dqp); - mutex_unlock(&q->qi_dqlist_lock); - delay(1); - mutex_lock(&q->qi_dqlist_lock); - goto again; - } - - gdqp = dqp->q_gdquot; - if (gdqp) - dqp->q_gdquot = NULL; - xfs_dqunlock(dqp); - - if (gdqp) - xfs_qm_dqrele(gdqp); - } -} - -/* - * Go through all the incore dquots of this file system and take them - * off the mplist and hashlist, if the dquot type matches the dqtype - * parameter. This is used when turning off quota accounting for - * users and/or groups, as well as when the filesystem is unmounting. - */ -STATIC int -xfs_qm_dqpurge_int( - struct xfs_mount *mp, - uint flags) -{ - struct xfs_quotainfo *q = mp->m_quotainfo; - struct xfs_dquot *dqp, *n; - uint dqtype; - int nmisses = 0; - LIST_HEAD (dispose_list); - - if (!q) - return 0; - - dqtype = (flags & XFS_QMOPT_UQUOTA) ? XFS_DQ_USER : 0; - dqtype |= (flags & XFS_QMOPT_PQUOTA) ? XFS_DQ_PROJ : 0; - dqtype |= (flags & XFS_QMOPT_GQUOTA) ? XFS_DQ_GROUP : 0; - - mutex_lock(&q->qi_dqlist_lock); - - /* - * In the first pass through all incore dquots of this filesystem, - * we release the group dquot pointers the user dquots may be - * carrying around as a hint. We need to do this irrespective of - * what's being turned off. - */ - xfs_qm_detach_gdquots(mp); - - /* - * Try to get rid of all of the unwanted dquots. - */ - list_for_each_entry_safe(dqp, n, &q->qi_dqlist, q_mplist) { - xfs_dqlock(dqp); - if ((dqp->dq_flags & dqtype) != 0 && - !(dqp->dq_flags & XFS_DQ_FREEING)) { - if (dqp->q_nrefs == 0) { - dqp->dq_flags |= XFS_DQ_FREEING; - list_move_tail(&dqp->q_mplist, &dispose_list); - } else - nmisses++; - } - xfs_dqunlock(dqp); - } - mutex_unlock(&q->qi_dqlist_lock); - - list_for_each_entry_safe(dqp, n, &dispose_list, q_mplist) - xfs_qm_dqpurge(dqp); - - return nmisses; -} - -int -xfs_qm_dqpurge_all( - xfs_mount_t *mp, - uint flags) -{ - int ndquots; - - /* - * Purge the dquot cache. - * None of the dquots should really be busy at this point. - */ - if (mp->m_quotainfo) { - while ((ndquots = xfs_qm_dqpurge_int(mp, flags))) { - delay(ndquots * 10); - } - } - return 0; -} - STATIC int xfs_qm_dqattach_one( xfs_inode_t *ip, @@ -749,15 +761,10 @@ xfs_qm_init_quotainfo( INIT_RADIX_TREE(&qinf->qi_gquota_tree, GFP_NOFS); mutex_init(&qinf->qi_tree_lock); - INIT_LIST_HEAD(&qinf->qi_dqlist); - mutex_init(&qinf->qi_dqlist_lock); - INIT_LIST_HEAD(&qinf->qi_lru_list); qinf->qi_lru_count = 0; mutex_init(&qinf->qi_lru_lock); - qinf->qi_dqreclaims = 0; - /* mutex used to serialize quotaoffs */ mutex_init(&qinf->qi_quotaofflock); @@ -854,9 +861,6 @@ xfs_qm_destroy_quotainfo( */ xfs_qm_rele_quotafs_ref(mp); - ASSERT(list_empty(&qi->qi_dqlist)); - mutex_destroy(&qi->qi_dqlist_lock); - if (qi->qi_uquotaip) { IRELE(qi->qi_uquotaip); qi->qi_uquotaip = NULL; /* paranoia */ @@ -1307,6 +1311,28 @@ error0: return error; } +STATIC int +xfs_qm_flush_one( + struct xfs_dquot *dqp) +{ + int error = 0; + + xfs_dqlock(dqp); + if (dqp->dq_flags & XFS_DQ_FREEING) + goto out_unlock; + if (!XFS_DQ_IS_DIRTY(dqp)) + goto out_unlock; + + if (!xfs_dqflock_nowait(dqp)) + xfs_dqflock_pushbuf_wait(dqp); + + error = xfs_qm_dqflush(dqp, 0); + +out_unlock: + xfs_dqunlock(dqp); + return error; +} + /* * Walk thru all the filesystem inodes and construct a consistent view * of the disk quota world. If the quotacheck fails, disable quotas. @@ -1315,7 +1341,7 @@ int xfs_qm_quotacheck( xfs_mount_t *mp) { - int done, count, error; + int done, count, error, error2; xfs_ino_t lastino; size_t structsz; xfs_inode_t *uip, *gip; @@ -1329,12 +1355,6 @@ xfs_qm_quotacheck( ASSERT(mp->m_quotainfo->qi_uquotaip || mp->m_quotainfo->qi_gquotaip); ASSERT(XFS_IS_QUOTA_RUNNING(mp)); - /* - * There should be no cached dquots. The (simplistic) quotacheck - * algorithm doesn't like that. - */ - ASSERT(list_empty(&mp->m_quotainfo->qi_dqlist)); - xfs_notice(mp, "Quotacheck needed: Please wait."); /* @@ -1373,12 +1393,21 @@ xfs_qm_quotacheck( } while (!done); /* - * We've made all the changes that we need to make incore. - * Flush them down to disk buffers if everything was updated - * successfully. + * We've made all the changes that we need to make incore. Flush them + * down to disk buffers if everything was updated successfully. */ - if (!error) - error = xfs_qm_dqflush_all(mp); + if (XFS_IS_UQUOTA_ON(mp)) + error = xfs_qm_dquot_walk(mp, XFS_DQ_USER, xfs_qm_flush_one); + if (XFS_IS_GQUOTA_ON(mp)) { + error2 = xfs_qm_dquot_walk(mp, XFS_DQ_GROUP, xfs_qm_flush_one); + if (!error) + error = error2; + } + if (XFS_IS_PQUOTA_ON(mp)) { + error2 = xfs_qm_dquot_walk(mp, XFS_DQ_PROJ, xfs_qm_flush_one); + if (!error) + error = error2; + } /* * We can get this error if we couldn't do a dquot allocation inside @@ -1517,13 +1546,9 @@ xfs_qm_dqfree_one( mutex_lock(&qi->qi_tree_lock); radix_tree_delete(XFS_DQUOT_TREE(qi, dqp->q_core.d_flags), be32_to_cpu(dqp->q_core.d_id)); - mutex_unlock(&qi->qi_tree_lock); - mutex_lock(&qi->qi_dqlist_lock); - list_del_init(&dqp->q_mplist); qi->qi_dquots--; - qi->qi_dqreclaims++; - mutex_unlock(&qi->qi_dqlist_lock); + mutex_unlock(&qi->qi_tree_lock); xfs_qm_dqdestroy(dqp); } @@ -1556,8 +1581,6 @@ xfs_qm_dqreclaim_one( return; } - ASSERT(!list_empty(&dqp->q_mplist)); - /* * Try to grab the flush lock. If this dquot is in the process of * getting flushed to disk, we don't want to reclaim it. -- cgit v1.2.3