diff options
Diffstat (limited to 'fs/xfs/xfs_qm.c')
| -rw-r--r-- | fs/xfs/xfs_qm.c | 863 |
1 files changed, 299 insertions, 564 deletions
diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c index 671f37eae1c..55c6afedc87 100644 --- a/fs/xfs/xfs_qm.c +++ b/fs/xfs/xfs_qm.c @@ -48,197 +48,189 @@ * quota functionality, including maintaining the freelist and hash * tables of dquots. */ -struct mutex xfs_Gqm_lock; -struct xfs_qm *xfs_Gqm; -uint ndquot; - -kmem_zone_t *qm_dqzone; -kmem_zone_t *qm_dqtrxzone; - -STATIC void xfs_qm_list_init(xfs_dqlist_t *, char *, int); -STATIC void xfs_qm_list_destroy(xfs_dqlist_t *); - STATIC int xfs_qm_init_quotainos(xfs_mount_t *); STATIC int xfs_qm_init_quotainfo(xfs_mount_t *); STATIC int xfs_qm_shake(struct shrinker *, struct shrink_control *); -static struct shrinker xfs_qm_shaker = { - .shrink = xfs_qm_shake, - .seeks = DEFAULT_SEEKS, -}; - /* - * Initialize the XQM structure. - * Note that there is not one quota manager per file system. + * 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. */ -STATIC struct xfs_qm * -xfs_Gqm_init(void) -{ - xfs_dqhash_t *udqhash, *gdqhash; - xfs_qm_t *xqm; - size_t hsize; - uint i; - - /* - * Initialize the dquot hash tables. - */ - udqhash = kmem_zalloc_greedy(&hsize, - XFS_QM_HASHSIZE_LOW * sizeof(xfs_dqhash_t), - XFS_QM_HASHSIZE_HIGH * sizeof(xfs_dqhash_t)); - if (!udqhash) - goto out; +#define XFS_DQ_LOOKUP_BATCH 32 - gdqhash = kmem_zalloc_large(hsize); - if (!gdqhash) - goto out_free_udqhash; - - hsize /= sizeof(xfs_dqhash_t); - ndquot = hsize << 8; +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; - xqm = kmem_zalloc(sizeof(xfs_qm_t), KM_SLEEP); - xqm->qm_dqhashmask = hsize - 1; - xqm->qm_usr_dqhtable = udqhash; - xqm->qm_grp_dqhtable = gdqhash; - ASSERT(xqm->qm_usr_dqhtable != NULL); - ASSERT(xqm->qm_grp_dqhtable != NULL); +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 < hsize; i++) { - xfs_qm_list_init(&(xqm->qm_usr_dqhtable[i]), "uxdqh", i); - xfs_qm_list_init(&(xqm->qm_grp_dqhtable[i]), "gxdqh", i); - } + for (i = 0; i < nr_found; i++) { + struct xfs_dquot *dqp = batch[i]; - /* - * Freelist of all dquots of all file systems - */ - INIT_LIST_HEAD(&xqm->qm_dqfrlist); - xqm->qm_dqfrlist_cnt = 0; - mutex_init(&xqm->qm_dqfrlist_lock); + next_index = be32_to_cpu(dqp->q_core.d_id) + 1; - /* - * dquot zone. we register our own low-memory callback. - */ - if (!qm_dqzone) { - xqm->qm_dqzone = kmem_zone_init(sizeof(xfs_dquot_t), - "xfs_dquots"); - qm_dqzone = xqm->qm_dqzone; - } else - xqm->qm_dqzone = qm_dqzone; + error = execute(batch[i]); + if (error == EAGAIN) { + skipped++; + continue; + } + if (error && last_error != EFSCORRUPTED) + last_error = error; + } - register_shrinker(&xfs_qm_shaker); + mutex_unlock(&qi->qi_tree_lock); - /* - * The t_dqinfo portion of transactions. - */ - if (!qm_dqtrxzone) { - xqm->qm_dqtrxzone = kmem_zone_init(sizeof(xfs_dquot_acct_t), - "xfs_dqtrx"); - qm_dqtrxzone = xqm->qm_dqtrxzone; - } else - xqm->qm_dqtrxzone = qm_dqtrxzone; + /* bail out if the filesystem is corrupted. */ + if (last_error == EFSCORRUPTED) { + skipped = 0; + break; + } + } - atomic_set(&xqm->qm_totaldquots, 0); - xqm->qm_dqfree_ratio = XFS_QM_DQFREE_RATIO; - xqm->qm_nrefs = 0; - return xqm; + if (skipped) { + delay(1); + goto restart; + } - out_free_udqhash: - kmem_free_large(udqhash); - out: - return NULL; + return last_error; } + /* - * Destroy the global quota manager when its reference count goes to zero. + * Purge a dquot from all tracking data structures and free it. */ -STATIC void -xfs_qm_destroy( - struct xfs_qm *xqm) +STATIC int +xfs_qm_dqpurge( + struct xfs_dquot *dqp) { - int hsize, i; + struct xfs_mount *mp = dqp->q_mount; + struct xfs_quotainfo *qi = mp->m_quotainfo; + struct xfs_dquot *gdqp = NULL; - ASSERT(xqm != NULL); - ASSERT(xqm->qm_nrefs == 0); + xfs_dqlock(dqp); + if ((dqp->dq_flags & XFS_DQ_FREEING) || dqp->q_nrefs != 0) { + xfs_dqunlock(dqp); + return EAGAIN; + } - unregister_shrinker(&xfs_qm_shaker); + /* + * 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; + } - mutex_lock(&xqm->qm_dqfrlist_lock); - ASSERT(list_empty(&xqm->qm_dqfrlist)); - mutex_unlock(&xqm->qm_dqfrlist_lock); + dqp->dq_flags |= XFS_DQ_FREEING; - hsize = xqm->qm_dqhashmask + 1; - for (i = 0; i < hsize; i++) { - xfs_qm_list_destroy(&(xqm->qm_usr_dqhtable[i])); - xfs_qm_list_destroy(&(xqm->qm_grp_dqhtable[i])); + /* + * 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); } - kmem_free_large(xqm->qm_usr_dqhtable); - kmem_free_large(xqm->qm_grp_dqhtable); - xqm->qm_usr_dqhtable = NULL; - xqm->qm_grp_dqhtable = NULL; - xqm->qm_dqhashmask = 0; - - kmem_free(xqm); -} -/* - * Called at mount time to let XQM know that another file system is - * starting quotas. This isn't crucial information as the individual mount - * structures are pretty independent, but it helps the XQM keep a - * global view of what's going on. - */ -/* ARGSUSED */ -STATIC int -xfs_qm_hold_quotafs_ref( - struct xfs_mount *mp) -{ /* - * Need to lock the xfs_Gqm structure for things like this. For example, - * the structure could disappear between the entry to this routine and - * a HOLD operation if not locked. + * 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. */ - mutex_lock(&xfs_Gqm_lock); + if (XFS_DQ_IS_DIRTY(dqp)) { + int error; - if (!xfs_Gqm) { - xfs_Gqm = xfs_Gqm_init(); - if (!xfs_Gqm) { - mutex_unlock(&xfs_Gqm_lock); - return ENOMEM; - } + /* + * 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 can keep a list of all filesystems with quotas mounted for - * debugging and statistical purposes, but ... - * Just take a reference and get out. + * We move dquots to the freelist as soon as their reference count + * hits zero, so it really should be on the freelist here. */ - xfs_Gqm->qm_nrefs++; - mutex_unlock(&xfs_Gqm_lock); + 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; } - /* - * Release the reference that a filesystem took at mount time, - * so that we know when we need to destroy the entire quota manager. + * Purge the dquot cache. */ -/* ARGSUSED */ -STATIC void -xfs_qm_rele_quotafs_ref( - struct xfs_mount *mp) +void +xfs_qm_dqpurge_all( + struct xfs_mount *mp, + uint flags) { - ASSERT(xfs_Gqm); - ASSERT(xfs_Gqm->qm_nrefs > 0); - - /* - * Destroy the entire XQM. If somebody mounts with quotaon, this'll - * be restarted. - */ - mutex_lock(&xfs_Gqm_lock); - if (--xfs_Gqm->qm_nrefs == 0) { - xfs_qm_destroy(xfs_Gqm); - xfs_Gqm = NULL; - } - mutex_unlock(&xfs_Gqm_lock); + 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); } /* @@ -379,175 +371,6 @@ 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, @@ -786,14 +609,6 @@ xfs_qm_dqdetach( } /* - * The hash chains and the mplist use the same xfs_dqhash structure as - * their list head, but we can take the mplist qh_lock and one of the - * hash qh_locks at the same time without any problem as they aren't - * related. - */ -static struct lock_class_key xfs_quota_mplist_class; - -/* * This initializes all the quota information that's kept in the * mount structure */ @@ -807,13 +622,6 @@ xfs_qm_init_quotainfo( ASSERT(XFS_IS_QUOTA_RUNNING(mp)); - /* - * Tell XQM that we exist as soon as possible. - */ - if ((error = xfs_qm_hold_quotafs_ref(mp))) { - return error; - } - qinf = mp->m_quotainfo = kmem_zalloc(sizeof(xfs_quotainfo_t), KM_SLEEP); /* @@ -826,11 +634,13 @@ xfs_qm_init_quotainfo( return error; } - INIT_LIST_HEAD(&qinf->qi_dqlist); - mutex_init(&qinf->qi_dqlist_lock); - lockdep_set_class(&qinf->qi_dqlist_lock, &xfs_quota_mplist_class); + INIT_RADIX_TREE(&qinf->qi_uquota_tree, GFP_NOFS); + INIT_RADIX_TREE(&qinf->qi_gquota_tree, GFP_NOFS); + mutex_init(&qinf->qi_tree_lock); - qinf->qi_dqreclaims = 0; + INIT_LIST_HEAD(&qinf->qi_lru_list); + qinf->qi_lru_count = 0; + mutex_init(&qinf->qi_lru_lock); /* mutex used to serialize quotaoffs */ mutex_init(&qinf->qi_quotaofflock); @@ -897,6 +707,9 @@ xfs_qm_init_quotainfo( qinf->qi_rtbwarnlimit = XFS_QM_RTBWARNLIMIT; } + qinf->qi_shrinker.shrink = xfs_qm_shake; + qinf->qi_shrinker.seeks = DEFAULT_SEEKS; + register_shrinker(&qinf->qi_shrinker); return 0; } @@ -914,17 +727,8 @@ xfs_qm_destroy_quotainfo( qi = mp->m_quotainfo; ASSERT(qi != NULL); - ASSERT(xfs_Gqm != NULL); - /* - * Release the reference that XQM kept, so that we know - * when the XQM structure should be freed. We cannot assume - * that xfs_Gqm is non-null after this point. - */ - xfs_qm_rele_quotafs_ref(mp); - - ASSERT(list_empty(&qi->qi_dqlist)); - mutex_destroy(&qi->qi_dqlist_lock); + unregister_shrinker(&qi->qi_shrinker); if (qi->qi_uquotaip) { IRELE(qi->qi_uquotaip); @@ -939,30 +743,6 @@ xfs_qm_destroy_quotainfo( mp->m_quotainfo = NULL; } - - -/* ------------------- PRIVATE STATIC FUNCTIONS ----------------------- */ - -/* ARGSUSED */ -STATIC void -xfs_qm_list_init( - xfs_dqlist_t *list, - char *str, - int n) -{ - mutex_init(&list->qh_lock); - INIT_LIST_HEAD(&list->qh_list); - list->qh_version = 0; - list->qh_nelems = 0; -} - -STATIC void -xfs_qm_list_destroy( - xfs_dqlist_t *list) -{ - mutex_destroy(&(list->qh_lock)); -} - /* * Create an inode and return with a reference already taken, but unlocked * This is how we create quota inodes @@ -1400,6 +1180,28 @@ 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. @@ -1408,7 +1210,7 @@ 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; @@ -1422,12 +1224,6 @@ 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."); /* @@ -1466,12 +1262,21 @@ 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 @@ -1499,7 +1304,7 @@ xfs_qm_quotacheck( * quotachecked status, since we won't be doing accounting for * that type anymore. */ - mp->m_qflags &= ~(XFS_OQUOTA_CHKD | XFS_UQUOTA_CHKD); + mp->m_qflags &= ~XFS_ALL_QUOTA_CHKD; mp->m_qflags |= flags; error_return: @@ -1511,7 +1316,6 @@ xfs_qm_quotacheck( * We must turn off quotas. */ ASSERT(mp->m_quotainfo != NULL); - ASSERT(xfs_Gqm != NULL); xfs_qm_destroy_quotainfo(mp); if (xfs_mount_reset_sbqflags(mp)) { xfs_warn(mp, @@ -1600,216 +1404,147 @@ xfs_qm_init_quotainos( return 0; } +STATIC void +xfs_qm_dqfree_one( + struct xfs_dquot *dqp) +{ + struct xfs_mount *mp = dqp->q_mount; + struct xfs_quotainfo *qi = mp->m_quotainfo; + 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)); -/* - * Pop the least recently used dquot off the freelist and recycle it. - */ -STATIC struct xfs_dquot * -xfs_qm_dqreclaim_one(void) + qi->qi_dquots--; + mutex_unlock(&qi->qi_tree_lock); + + xfs_qm_dqdestroy(dqp); +} + +STATIC void +xfs_qm_dqreclaim_one( + struct xfs_dquot *dqp, + struct list_head *dispose_list) { - struct xfs_dquot *dqp; - int restarts = 0; + struct xfs_mount *mp = dqp->q_mount; + struct xfs_quotainfo *qi = mp->m_quotainfo; + int error; - mutex_lock(&xfs_Gqm->qm_dqfrlist_lock); -restart: - list_for_each_entry(dqp, &xfs_Gqm->qm_dqfrlist, q_freelist) { - struct xfs_mount *mp = dqp->q_mount; + if (!xfs_dqlock_nowait(dqp)) + goto out_busy; - if (!xfs_dqlock_nowait(dqp)) - continue; + /* + * This dquot has acquired a reference in the meantime remove it from + * the freelist and try again. + */ + if (dqp->q_nrefs) { + xfs_dqunlock(dqp); - /* - * This dquot has already been grabbed by dqlookup. - * Remove it from the freelist and try again. - */ - if (dqp->q_nrefs) { - trace_xfs_dqreclaim_want(dqp); - XQM_STATS_INC(xqmstats.xs_qm_dqwants); - - list_del_init(&dqp->q_freelist); - xfs_Gqm->qm_dqfrlist_cnt--; - restarts++; - goto dqunlock; - } + trace_xfs_dqreclaim_want(dqp); + XFS_STATS_INC(xs_qm_dqwants); - ASSERT(dqp->q_hash); - ASSERT(!list_empty(&dqp->q_mplist)); + list_del_init(&dqp->q_lru); + qi->qi_lru_count--; + XFS_STATS_DEC(xs_qm_dquot_unused); + return; + } - /* - * 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. - */ - if (!xfs_dqflock_nowait(dqp)) - goto dqunlock; + /* + * 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. + */ + if (!xfs_dqflock_nowait(dqp)) + goto out_busy; + + /* + * We have the flush lock so we know that this is not in the + * process of being flushed. So, if this is dirty, flush it + * DELWRI so that we don't get a freelist infested with + * dirty dquots. + */ + if (XFS_DQ_IS_DIRTY(dqp)) { + trace_xfs_dqreclaim_dirty(dqp); /* - * We have the flush lock so we know that this is not in the - * process of being flushed. So, if this is dirty, flush it - * DELWRI so that we don't get a freelist infested with - * dirty dquots. + * We flush it delayed write, so don't bother releasing the + * freelist lock. */ - if (XFS_DQ_IS_DIRTY(dqp)) { - int error; - - trace_xfs_dqreclaim_dirty(dqp); - - /* - * We flush it delayed write, so don't bother - * releasing the freelist lock. - */ - error = xfs_qm_dqflush(dqp, SYNC_TRYLOCK); - if (error) { - xfs_warn(mp, "%s: dquot %p flush failed", - __func__, dqp); - } - goto dqunlock; + error = xfs_qm_dqflush(dqp, 0); + if (error) { + xfs_warn(mp, "%s: dquot %p flush failed", + __func__, dqp); } - xfs_dqfunlock(dqp); /* - * Prevent lookup now that we are going to reclaim the dquot. - * Once XFS_DQ_FREEING is set lookup won't touch the dquot, - * thus we can drop the lock now. + * Give the dquot another try on the freelist, as the + * flushing will take some time. */ - dqp->dq_flags |= XFS_DQ_FREEING; - xfs_dqunlock(dqp); - - mutex_lock(&dqp->q_hash->qh_lock); - list_del_init(&dqp->q_hashlist); - dqp->q_hash->qh_version++; - mutex_unlock(&dqp->q_hash->qh_lock); - - mutex_lock(&mp->m_quotainfo->qi_dqlist_lock); - list_del_init(&dqp->q_mplist); - mp->m_quotainfo->qi_dquots--; - mp->m_quotainfo->qi_dqreclaims++; - mutex_unlock(&mp->m_quotainfo->qi_dqlist_lock); + goto out_busy; + } + xfs_dqfunlock(dqp); - ASSERT(dqp->q_nrefs == 0); - list_del_init(&dqp->q_freelist); - xfs_Gqm->qm_dqfrlist_cnt--; + /* + * Prevent lookups now that we are past the point of no return. + */ + dqp->dq_flags |= XFS_DQ_FREEING; + xfs_dqunlock(dqp); - mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock); - return dqp; -dqunlock: - xfs_dqunlock(dqp); - if (restarts >= XFS_QM_RECLAIM_MAX_RESTARTS) - break; - goto restart; - } + ASSERT(dqp->q_nrefs == 0); + list_move_tail(&dqp->q_lru, dispose_list); + qi->qi_lru_count--; + XFS_STATS_DEC(xs_qm_dquot_unused); - mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock); - return NULL; -} + trace_xfs_dqreclaim_done(dqp); + XFS_STATS_INC(xs_qm_dqreclaims); + return; -/* - * Traverse the freelist of dquots and attempt to reclaim a maximum of - * 'howmany' dquots. This operation races with dqlookup(), and attempts to - * favor the lookup function ... - */ -STATIC int -xfs_qm_shake_freelist( - int howmany) -{ - int nreclaimed = 0; - xfs_dquot_t *dqp; +out_busy: + xfs_dqunlock(dqp); - if (howmany <= 0) - return 0; + /* + * Move the dquot to the tail of the list so that we don't spin on it. + */ + list_move_tail(&dqp->q_lru, &qi->qi_lru_list); - while (nreclaimed < howmany) { - dqp = xfs_qm_dqreclaim_one(); - if (!dqp) - return nreclaimed; - xfs_qm_dqdestroy(dqp); - nreclaimed++; - } - return nreclaimed; + trace_xfs_dqreclaim_busy(dqp); + XFS_STATS_INC(xs_qm_dqreclaim_misses); } -/* - * The kmem_shake interface is invoked when memory is running low. - */ -/* ARGSUSED */ STATIC int xfs_qm_shake( - struct shrinker *shrink, - struct shrink_control *sc) + struct shrinker *shrink, + struct shrink_control *sc) { - int ndqused, nfree, n; - gfp_t gfp_mask = sc->gfp_mask; - - if (!kmem_shake_allow(gfp_mask)) - return 0; - if (!xfs_Gqm) - return 0; - - nfree = xfs_Gqm->qm_dqfrlist_cnt; /* free dquots */ - /* incore dquots in all f/s's */ - ndqused = atomic_read(&xfs_Gqm->qm_totaldquots) - nfree; - - ASSERT(ndqused >= 0); + struct xfs_quotainfo *qi = + container_of(shrink, struct xfs_quotainfo, qi_shrinker); + int nr_to_scan = sc->nr_to_scan; + LIST_HEAD (dispose_list); + struct xfs_dquot *dqp; - if (nfree <= ndqused && nfree < ndquot) + if ((sc->gfp_mask & (__GFP_FS|__GFP_WAIT)) != (__GFP_FS|__GFP_WAIT)) return 0; + if (!nr_to_scan) + goto out; - ndqused *= xfs_Gqm->qm_dqfree_ratio; /* target # of free dquots */ - n = nfree - ndqused - ndquot; /* # over target */ - - return xfs_qm_shake_freelist(MAX(nfree, n)); -} - - -/*------------------------------------------------------------------*/ - -/* - * Return a new incore dquot. Depending on the number of - * dquots in the system, we either allocate a new one on the kernel heap, - * or reclaim a free one. - * Return value is B_TRUE if we allocated a new dquot, B_FALSE if we managed - * to reclaim an existing one from the freelist. - */ -boolean_t -xfs_qm_dqalloc_incore( - xfs_dquot_t **O_dqpp) -{ - xfs_dquot_t *dqp; - - /* - * Check against high water mark to see if we want to pop - * a nincompoop dquot off the freelist. - */ - if (atomic_read(&xfs_Gqm->qm_totaldquots) >= ndquot) { - /* - * Try to recycle a dquot from the freelist. - */ - if ((dqp = xfs_qm_dqreclaim_one())) { - XQM_STATS_INC(xqmstats.xs_qm_dqreclaims); - /* - * Just zero the core here. The rest will get - * reinitialized by caller. XXX we shouldn't even - * do this zero ... - */ - memset(&dqp->q_core, 0, sizeof(dqp->q_core)); - *O_dqpp = dqp; - return B_FALSE; - } - XQM_STATS_INC(xqmstats.xs_qm_dqreclaim_misses); + mutex_lock(&qi->qi_lru_lock); + while (!list_empty(&qi->qi_lru_list)) { + if (nr_to_scan-- <= 0) + break; + dqp = list_first_entry(&qi->qi_lru_list, struct xfs_dquot, + q_lru); + xfs_qm_dqreclaim_one(dqp, &dispose_list); } + mutex_unlock(&qi->qi_lru_lock); - /* - * Allocate a brand new dquot on the kernel heap and return it - * to the caller to initialize. - */ - ASSERT(xfs_Gqm->qm_dqzone != NULL); - *O_dqpp = kmem_zone_zalloc(xfs_Gqm->qm_dqzone, KM_SLEEP); - atomic_inc(&xfs_Gqm->qm_totaldquots); - - return B_TRUE; + while (!list_empty(&dispose_list)) { + dqp = list_first_entry(&dispose_list, struct xfs_dquot, q_lru); + list_del_init(&dqp->q_lru); + xfs_qm_dqfree_one(dqp); + } +out: + return (qi->qi_lru_count / 100) * sysctl_vfs_cache_pressure; } - /* * Start a transaction and write the incore superblock changes to * disk. flags parameter indicates which fields have changed. |