diff options
Diffstat (limited to 'fs/dquot.c')
| -rw-r--r-- | fs/dquot.c | 594 |
1 files changed, 396 insertions, 198 deletions
diff --git a/fs/dquot.c b/fs/dquot.c index c237ccc8581c..bca3cac4bee7 100644 --- a/fs/dquot.c +++ b/fs/dquot.c @@ -87,14 +87,17 @@ #define __DQUOT_PARANOIA /* - * There are two quota SMP locks. dq_list_lock protects all lists with quotas - * and quota formats and also dqstats structure containing statistics about the - * lists. dq_data_lock protects data from dq_dqb and also mem_dqinfo structures - * and also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes. + * There are three quota SMP locks. dq_list_lock protects all lists with quotas + * and quota formats, dqstats structure containing statistics about the lists + * dq_data_lock protects data from dq_dqb and also mem_dqinfo structures and + * also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes. * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly - * in inode_add_bytes() and inode_sub_bytes(). + * in inode_add_bytes() and inode_sub_bytes(). dq_state_lock protects + * modifications of quota state (on quotaon and quotaoff) and readers who care + * about latest values take it as well. * - * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock + * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock, + * dq_list_lock > dq_state_lock * * Note that some things (eg. sb pointer, type, id) doesn't change during * the life of the dquot structure and so needn't to be protected by a lock @@ -103,12 +106,7 @@ * operation is just reading pointers from inode (or not using them at all) the * read lock is enough. If pointers are altered function must hold write lock * (these locking rules also apply for S_NOQUOTA flag in the inode - note that - * for altering the flag i_mutex is also needed). If operation is holding - * reference to dquot in other way (e.g. quotactl ops) it must be guarded by - * dqonoff_mutex. - * This locking assures that: - * a) update/access to dquot pointers in inode is serialized - * b) everyone is guarded against invalidate_dquots() + * for altering the flag i_mutex is also needed). * * Each dquot has its dq_lock mutex. Locked dquots might not be referenced * from inodes (dquot_alloc_space() and such don't check the dq_lock). @@ -122,10 +120,17 @@ * Lock ordering (including related VFS locks) is the following: * i_mutex > dqonoff_sem > journal_lock > dqptr_sem > dquot->dq_lock > * dqio_mutex + * The lock ordering of dqptr_sem imposed by quota code is only dqonoff_sem > + * dqptr_sem. But filesystem has to count with the fact that functions such as + * dquot_alloc_space() acquire dqptr_sem and they usually have to be called + * from inside a transaction to keep filesystem consistency after a crash. Also + * filesystems usually want to do some IO on dquot from ->mark_dirty which is + * called with dqptr_sem held. * i_mutex on quota files is special (it's below dqio_mutex) */ static DEFINE_SPINLOCK(dq_list_lock); +static DEFINE_SPINLOCK(dq_state_lock); DEFINE_SPINLOCK(dq_data_lock); static char *quotatypes[] = INITQFNAMES; @@ -211,8 +216,6 @@ static struct hlist_head *dquot_hash; struct dqstats dqstats; -static void dqput(struct dquot *dquot); - static inline unsigned int hashfn(const struct super_block *sb, unsigned int id, int type) { @@ -415,11 +418,22 @@ out_dqlock: return ret; } +void dquot_destroy(struct dquot *dquot) +{ + kmem_cache_free(dquot_cachep, dquot); +} +EXPORT_SYMBOL(dquot_destroy); + +static inline void do_destroy_dquot(struct dquot *dquot) +{ + dquot->dq_sb->dq_op->destroy_dquot(dquot); +} + /* Invalidate all dquots on the list. Note that this function is called after * quota is disabled and pointers from inodes removed so there cannot be new * quota users. There can still be some users of quotas due to inodes being * just deleted or pruned by prune_icache() (those are not attached to any - * list). We have to wait for such users. + * list) or parallel quotactl call. We have to wait for such users. */ static void invalidate_dquots(struct super_block *sb, int type) { @@ -463,11 +477,46 @@ restart: remove_dquot_hash(dquot); remove_free_dquot(dquot); remove_inuse(dquot); - kmem_cache_free(dquot_cachep, dquot); + do_destroy_dquot(dquot); } spin_unlock(&dq_list_lock); } +/* Call callback for every active dquot on given filesystem */ +int dquot_scan_active(struct super_block *sb, + int (*fn)(struct dquot *dquot, unsigned long priv), + unsigned long priv) +{ + struct dquot *dquot, *old_dquot = NULL; + int ret = 0; + + mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); + spin_lock(&dq_list_lock); + list_for_each_entry(dquot, &inuse_list, dq_inuse) { + if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) + continue; + if (dquot->dq_sb != sb) + continue; + /* Now we have active dquot so we can just increase use count */ + atomic_inc(&dquot->dq_count); + dqstats.lookups++; + spin_unlock(&dq_list_lock); + dqput(old_dquot); + old_dquot = dquot; + ret = fn(dquot, priv); + if (ret < 0) + goto out; + spin_lock(&dq_list_lock); + /* We are safe to continue now because our dquot could not + * be moved out of the inuse list while we hold the reference */ + } + spin_unlock(&dq_list_lock); +out: + dqput(old_dquot); + mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); + return ret; +} + int vfs_quota_sync(struct super_block *sb, int type) { struct list_head *dirty; @@ -479,7 +528,7 @@ int vfs_quota_sync(struct super_block *sb, int type) for (cnt = 0; cnt < MAXQUOTAS; cnt++) { if (type != -1 && cnt != type) continue; - if (!sb_has_quota_enabled(sb, cnt)) + if (!sb_has_quota_active(sb, cnt)) continue; spin_lock(&dq_list_lock); dirty = &dqopt->info[cnt].dqi_dirty_list; @@ -504,8 +553,8 @@ int vfs_quota_sync(struct super_block *sb, int type) } for (cnt = 0; cnt < MAXQUOTAS; cnt++) - if ((cnt == type || type == -1) && sb_has_quota_enabled(sb, cnt) - && info_dirty(&dqopt->info[cnt])) + if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt) + && info_dirty(&dqopt->info[cnt])) sb->dq_op->write_info(sb, cnt); spin_lock(&dq_list_lock); dqstats.syncs++; @@ -527,7 +576,7 @@ static void prune_dqcache(int count) remove_dquot_hash(dquot); remove_free_dquot(dquot); remove_inuse(dquot); - kmem_cache_free(dquot_cachep, dquot); + do_destroy_dquot(dquot); count--; head = free_dquots.prev; } @@ -556,9 +605,8 @@ static struct shrinker dqcache_shrinker = { /* * Put reference to dquot * NOTE: If you change this function please check whether dqput_blocks() works right... - * MUST be called with either dqptr_sem or dqonoff_mutex held */ -static void dqput(struct dquot *dquot) +void dqput(struct dquot *dquot) { int ret; @@ -584,7 +632,7 @@ we_slept: /* We have more than one user... nothing to do */ atomic_dec(&dquot->dq_count); /* Releasing dquot during quotaoff phase? */ - if (!sb_has_quota_enabled(dquot->dq_sb, dquot->dq_type) && + if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_type) && atomic_read(&dquot->dq_count) == 1) wake_up(&dquot->dq_wait_unused); spin_unlock(&dq_list_lock); @@ -625,11 +673,17 @@ we_slept: spin_unlock(&dq_list_lock); } +struct dquot *dquot_alloc(struct super_block *sb, int type) +{ + return kmem_cache_zalloc(dquot_cachep, GFP_NOFS); +} +EXPORT_SYMBOL(dquot_alloc); + static struct dquot *get_empty_dquot(struct super_block *sb, int type) { struct dquot *dquot; - dquot = kmem_cache_zalloc(dquot_cachep, GFP_NOFS); + dquot = sb->dq_op->alloc_dquot(sb, type); if(!dquot) return NODQUOT; @@ -648,17 +702,29 @@ static struct dquot *get_empty_dquot(struct super_block *sb, int type) /* * Get reference to dquot - * MUST be called with either dqptr_sem or dqonoff_mutex held + * + * Locking is slightly tricky here. We are guarded from parallel quotaoff() + * destroying our dquot by: + * a) checking for quota flags under dq_list_lock and + * b) getting a reference to dquot before we release dq_list_lock */ -static struct dquot *dqget(struct super_block *sb, unsigned int id, int type) +struct dquot *dqget(struct super_block *sb, unsigned int id, int type) { unsigned int hashent = hashfn(sb, id, type); - struct dquot *dquot, *empty = NODQUOT; + struct dquot *dquot = NODQUOT, *empty = NODQUOT; - if (!sb_has_quota_enabled(sb, type)) + if (!sb_has_quota_active(sb, type)) return NODQUOT; we_slept: spin_lock(&dq_list_lock); + spin_lock(&dq_state_lock); + if (!sb_has_quota_active(sb, type)) { + spin_unlock(&dq_state_lock); + spin_unlock(&dq_list_lock); + goto out; + } + spin_unlock(&dq_state_lock); + if ((dquot = find_dquot(hashent, sb, id, type)) == NODQUOT) { if (empty == NODQUOT) { spin_unlock(&dq_list_lock); @@ -667,6 +733,7 @@ we_slept: goto we_slept; } dquot = empty; + empty = NODQUOT; dquot->dq_id = id; /* all dquots go on the inuse_list */ put_inuse(dquot); @@ -681,8 +748,6 @@ we_slept: dqstats.cache_hits++; dqstats.lookups++; spin_unlock(&dq_list_lock); - if (empty) - kmem_cache_free(dquot_cachep, empty); } /* Wait for dq_lock - after this we know that either dquot_release() is already * finished or it will be canceled due to dq_count > 1 test */ @@ -690,11 +755,15 @@ we_slept: /* Read the dquot and instantiate it (everything done only if needed) */ if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && sb->dq_op->acquire_dquot(dquot) < 0) { dqput(dquot); - return NODQUOT; + dquot = NODQUOT; + goto out; } #ifdef __DQUOT_PARANOIA BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */ #endif +out: + if (empty) + do_destroy_dquot(empty); return dquot; } @@ -820,7 +889,7 @@ static void drop_dquot_ref(struct super_block *sb, int type) } } -static inline void dquot_incr_inodes(struct dquot *dquot, unsigned long number) +static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number) { dquot->dq_dqb.dqb_curinodes += number; } @@ -830,9 +899,10 @@ static inline void dquot_incr_space(struct dquot *dquot, qsize_t number) dquot->dq_dqb.dqb_curspace += number; } -static inline void dquot_decr_inodes(struct dquot *dquot, unsigned long number) +static inline void dquot_decr_inodes(struct dquot *dquot, qsize_t number) { - if (dquot->dq_dqb.dqb_curinodes > number) + if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || + dquot->dq_dqb.dqb_curinodes >= number) dquot->dq_dqb.dqb_curinodes -= number; else dquot->dq_dqb.dqb_curinodes = 0; @@ -843,11 +913,12 @@ static inline void dquot_decr_inodes(struct dquot *dquot, unsigned long number) static inline void dquot_decr_space(struct dquot *dquot, qsize_t number) { - if (dquot->dq_dqb.dqb_curspace > number) + if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE || + dquot->dq_dqb.dqb_curspace >= number) dquot->dq_dqb.dqb_curspace -= number; else dquot->dq_dqb.dqb_curspace = 0; - if (toqb(dquot->dq_dqb.dqb_curspace) <= dquot->dq_dqb.dqb_bsoftlimit) + if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) dquot->dq_dqb.dqb_btime = (time_t) 0; clear_bit(DQ_BLKS_B, &dquot->dq_flags); } @@ -1023,10 +1094,11 @@ static inline char ignore_hardlimit(struct dquot *dquot) } /* needs dq_data_lock */ -static int check_idq(struct dquot *dquot, ulong inodes, char *warntype) +static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype) { *warntype = QUOTA_NL_NOWARN; - if (inodes <= 0 || test_bit(DQ_FAKE_B, &dquot->dq_flags)) + if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) || + test_bit(DQ_FAKE_B, &dquot->dq_flags)) return QUOTA_OK; if (dquot->dq_dqb.dqb_ihardlimit && @@ -1058,11 +1130,12 @@ static int check_idq(struct dquot *dquot, ulong inodes, char *warntype) static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype) { *warntype = QUOTA_NL_NOWARN; - if (space <= 0 || test_bit(DQ_FAKE_B, &dquot->dq_flags)) + if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) || + test_bit(DQ_FAKE_B, &dquot->dq_flags)) return QUOTA_OK; if (dquot->dq_dqb.dqb_bhardlimit && - toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bhardlimit && + dquot->dq_dqb.dqb_curspace + space > dquot->dq_dqb.dqb_bhardlimit && !ignore_hardlimit(dquot)) { if (!prealloc) *warntype = QUOTA_NL_BHARDWARN; @@ -1070,7 +1143,7 @@ static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *war } if (dquot->dq_dqb.dqb_bsoftlimit && - toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit && + dquot->dq_dqb.dqb_curspace + space > dquot->dq_dqb.dqb_bsoftlimit && dquot->dq_dqb.dqb_btime && get_seconds() >= dquot->dq_dqb.dqb_btime && !ignore_hardlimit(dquot)) { if (!prealloc) @@ -1079,7 +1152,7 @@ static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *war } if (dquot->dq_dqb.dqb_bsoftlimit && - toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit && + dquot->dq_dqb.dqb_curspace + space > dquot->dq_dqb.dqb_bsoftlimit && dquot->dq_dqb.dqb_btime == 0) { if (!prealloc) { *warntype = QUOTA_NL_BSOFTWARN; @@ -1096,10 +1169,11 @@ static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *war return QUOTA_OK; } -static int info_idq_free(struct dquot *dquot, ulong inodes) +static int info_idq_free(struct dquot *dquot, qsize_t inodes) { if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || - dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit) + dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit || + !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type)) return QUOTA_NL_NOWARN; if (dquot->dq_dqb.dqb_curinodes - inodes <= dquot->dq_dqb.dqb_isoftlimit) @@ -1113,71 +1187,88 @@ static int info_idq_free(struct dquot *dquot, ulong inodes) static int info_bdq_free(struct dquot *dquot, qsize_t space) { if (test_bit(DQ_FAKE_B, &dquot->dq_flags) || - toqb(dquot->dq_dqb.dqb_curspace) <= dquot->dq_dqb.dqb_bsoftlimit) + dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit) return QUOTA_NL_NOWARN; - if (toqb(dquot->dq_dqb.dqb_curspace - space) <= - dquot->dq_dqb.dqb_bsoftlimit) + if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit) return QUOTA_NL_BSOFTBELOW; - if (toqb(dquot->dq_dqb.dqb_curspace) >= dquot->dq_dqb.dqb_bhardlimit && - toqb(dquot->dq_dqb.dqb_curspace - space) < - dquot->dq_dqb.dqb_bhardlimit) + if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit && + dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit) return QUOTA_NL_BHARDBELOW; return QUOTA_NL_NOWARN; } /* * Initialize quota pointers in inode - * Transaction must be started at entry + * We do things in a bit complicated way but by that we avoid calling + * dqget() and thus filesystem callbacks under dqptr_sem. */ int dquot_initialize(struct inode *inode, int type) { unsigned int id = 0; int cnt, ret = 0; + struct dquot *got[MAXQUOTAS] = { NODQUOT, NODQUOT }; + struct super_block *sb = inode->i_sb; /* First test before acquiring mutex - solves deadlocks when we * re-enter the quota code and are already holding the mutex */ if (IS_NOQUOTA(inode)) return 0; - down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); + + /* First get references to structures we might need. */ + for (cnt = 0; cnt < MAXQUOTAS; cnt++) { + if (type != -1 && cnt != type) + continue; + switch (cnt) { + case USRQUOTA: + id = inode->i_uid; + break; + case GRPQUOTA: + id = inode->i_gid; + break; + } + got[cnt] = dqget(sb, id, cnt); + } + + down_write(&sb_dqopt(sb)->dqptr_sem); /* Having dqptr_sem we know NOQUOTA flags can't be altered... */ if (IS_NOQUOTA(inode)) goto out_err; for (cnt = 0; cnt < MAXQUOTAS; cnt++) { if (type != -1 && cnt != type) continue; + /* Avoid races with quotaoff() */ + if (!sb_has_quota_active(sb, cnt)) + continue; if (inode->i_dquot[cnt] == NODQUOT) { - switch (cnt) { - case USRQUOTA: - id = inode->i_uid; - break; - case GRPQUOTA: - id = inode->i_gid; - break; - } - inode->i_dquot[cnt] = dqget(inode->i_sb, id, cnt); + inode->i_dquot[cnt] = got[cnt]; + got[cnt] = NODQUOT; } } out_err: - up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); + up_write(&sb_dqopt(sb)->dqptr_sem); + /* Drop unused references */ + for (cnt = 0; cnt < MAXQUOTAS; cnt++) + dqput(got[cnt]); return ret; } /* * Release all quotas referenced by inode - * Transaction must be started at an entry */ int dquot_drop(struct inode *inode) { int cnt; + struct dquot *put[MAXQUOTAS]; down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); for (cnt = 0; cnt < MAXQUOTAS; cnt++) { - if (inode->i_dquot[cnt] != NODQUOT) { - dqput(inode->i_dquot[cnt]); - inode->i_dquot[cnt] = NODQUOT; - } + put[cnt] = inode->i_dquot[cnt]; + inode->i_dquot[cnt] = NODQUOT; } up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); + + for (cnt = 0; cnt < MAXQUOTAS; cnt++) + dqput(put[cnt]); return 0; } @@ -1264,7 +1355,7 @@ warn_put_all: /* * This operation can block, but only after everything is updated */ -int dquot_alloc_inode(const struct inode *inode, unsigned long number) +int dquot_alloc_inode(const struct inode *inode, qsize_t number) { int cnt, ret = NO_QUOTA; char warntype[MAXQUOTAS]; @@ -1349,7 +1440,7 @@ out_sub: /* * This operation can block, but only after everything is updated */ -int dquot_free_inode(const struct inode *inode, unsigned long number) +int dquot_free_inode(const struct inode *inode, qsize_t number) { unsigned int cnt; char warntype[MAXQUOTAS]; @@ -1393,8 +1484,9 @@ int dquot_transfer(struct inode *inode, struct iattr *iattr) qsize_t space; struct dquot *transfer_from[MAXQUOTAS]; struct dquot *transfer_to[MAXQUOTAS]; - int cnt, ret = NO_QUOTA, chuid = (iattr->ia_valid & ATTR_UID) && inode->i_uid != iattr->ia_uid, - chgid = (iattr->ia_valid & ATTR_GID) && inode->i_gid != iattr->ia_gid; + int cnt, ret = QUOTA_OK; + int chuid = iattr->ia_valid & ATTR_UID && inode->i_uid != iattr->ia_uid, + chgid = iattr->ia_valid & ATTR_GID && inode->i_gid != iattr->ia_gid; char warntype_to[MAXQUOTAS]; char warntype_from_inodes[MAXQUOTAS], warntype_from_space[MAXQUOTAS]; @@ -1402,21 +1494,11 @@ int dquot_transfer(struct inode *inode, struct iattr *iattr) * re-enter the quota code and are already holding the mutex */ if (IS_NOQUOTA(inode)) return QUOTA_OK; - /* Clear the arrays */ + /* Initialize the arrays */ for (cnt = 0; cnt < MAXQUOTAS; cnt++) { - transfer_to[cnt] = transfer_from[cnt] = NODQUOT; + transfer_from[cnt] = NODQUOT; + transfer_to[cnt] = NODQUOT; warntype_to[cnt] = QUOTA_NL_NOWARN; - } - down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); - /* Now recheck reliably when holding dqptr_sem */ - if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ - up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); - return QUOTA_OK; - } - /* First build the transfer_to list - here we can block on - * reading/instantiating of dquots. We know that the transaction for - * us was already started so we don't violate lock ranking here */ - for (cnt = 0; cnt < MAXQUOTAS; cnt++) { switch (cnt) { case USRQUOTA: if (!chuid) @@ -1430,6 +1512,13 @@ int dquot_transfer(struct inode *inode, struct iattr *iattr) break; } } + + down_write(&sb_dqopt(inode->i_sb)->dqptr_sem); + /* Now recheck reliably when holding dqptr_sem */ + if (IS_NOQUOTA(inode)) { /* File without quota accounting? */ + up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); + goto put_all; + } spin_lock(&dq_data_lock); space = inode_get_bytes(inode); /* Build the transfer_from list and check the limits */ @@ -1440,7 +1529,7 @@ int dquot_transfer(struct inode *inode, struct iattr *iattr) if (check_idq(transfer_to[cnt], 1, warntype_to + cnt) == NO_QUOTA || check_bdq(transfer_to[cnt], space, 0, warntype_to + cnt) == NO_QUOTA) - goto warn_put_all; + goto over_quota; } /* @@ -1468,34 +1557,43 @@ int dquot_transfer(struct inode *inode, struct iattr *iattr) inode->i_dquot[cnt] = transfer_to[cnt]; } - ret = QUOTA_OK; -warn_put_all: spin_unlock(&dq_data_lock); + up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); + /* Dirtify all the dquots - this can block when journalling */ for (cnt = 0; cnt < MAXQUOTAS; cnt++) { if (transfer_from[cnt]) mark_dquot_dirty(transfer_from[cnt]); - if (transfer_to[cnt]) + if (transfer_to[cnt]) { mark_dquot_dirty(transfer_to[cnt]); + /* The reference we got is transferred to the inode */ + transfer_to[cnt] = NODQUOT; + } } +warn_put_all: flush_warnings(transfer_to, warntype_to); flush_warnings(transfer_from, warntype_from_inodes); flush_warnings(transfer_from, warntype_from_space); - +put_all: for (cnt = 0; cnt < MAXQUOTAS; cnt++) { - if (ret == QUOTA_OK && transfer_from[cnt] != NODQUOT) - dqput(transfer_from[cnt]); - if (ret == NO_QUOTA && transfer_to[cnt] != NODQUOT) - dqput(transfer_to[cnt]); + dqput(transfer_from[cnt]); + dqput(transfer_to[cnt]); } - up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); return ret; +over_quota: + spin_unlock(&dq_data_lock); + up_write(&sb_dqopt(inode->i_sb)->dqptr_sem); + /* Clear dquot pointers we don't want to dqput() */ + for (cnt = 0; cnt < MAXQUOTAS; cnt++) + transfer_from[cnt] = NODQUOT; + ret = NO_QUOTA; + goto warn_put_all; } /* Wrapper for transferring ownership of an inode */ int vfs_dq_transfer(struct inode *inode, struct iattr *iattr) { - if (sb_any_quota_enabled(inode->i_sb) && !IS_NOQUOTA(inode)) { + if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode)) { vfs_dq_init(inode); if (inode->i_sb->dq_op->transfer(inode, iattr) == NO_QUOTA) return 1; @@ -1533,54 +1631,27 @@ struct dquot_operations dquot_operations = { .acquire_dquot = dquot_acquire, .release_dquot = dquot_release, .mark_dirty = dquot_mark_dquot_dirty, - .write_info = dquot_commit_info + .write_info = dquot_commit_info, + .alloc_dquot = dquot_alloc, + .destroy_dquot = dquot_destroy, }; -static inline void set_enable_flags(struct quota_info *dqopt, int type) -{ - switch (type) { - case USRQUOTA: - dqopt->flags |= DQUOT_USR_ENABLED; - dqopt->flags &= ~DQUOT_USR_SUSPENDED; - break; - case GRPQUOTA: - dqopt->flags |= DQUOT_GRP_ENABLED; - dqopt->flags &= ~DQUOT_GRP_SUSPENDED; - break; - } -} - -static inline void reset_enable_flags(struct quota_info *dqopt, int type, - int remount) -{ - switch (type) { - case USRQUOTA: - dqopt->flags &= ~DQUOT_USR_ENABLED; - if (remount) - dqopt->flags |= DQUOT_USR_SUSPENDED; - else - dqopt->flags &= ~DQUOT_USR_SUSPENDED; - break; - case GRPQUOTA: - dqopt->flags &= ~DQUOT_GRP_ENABLED; - if (remount) - dqopt->flags |= DQUOT_GRP_SUSPENDED; - else - dqopt->flags &= ~DQUOT_GRP_SUSPENDED; - break; - } -} - - /* * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount) */ -int vfs_quota_off(struct super_block *sb, int type, int remount) +int vfs_quota_disable(struct super_block *sb, int type, unsigned int flags) { int cnt, ret = 0; struct quota_info *dqopt = sb_dqopt(sb); struct inode *toputinode[MAXQUOTAS]; + /* Cannot turn off usage accounting without turning off limits, or + * suspend quotas and simultaneously turn quotas off. */ + if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) + || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED | + DQUOT_USAGE_ENABLED))) + return -EINVAL; + /* We need to serialize quota_off() for device */ mutex_lock(&dqopt->dqonoff_mutex); @@ -1589,7 +1660,7 @@ int vfs_quota_off(struct super_block *sb, int type, int remount) * sometimes we are called when fill_super() failed and calling * sync_fs() in such cases does no good. */ - if (!sb_any_quota_enabled(sb) && !sb_any_quota_suspended(sb)) { + if (!sb_any_quota_loaded(sb)) { mutex_unlock(&dqopt->dqonoff_mutex); return 0; } @@ -1597,17 +1668,33 @@ int vfs_quota_off(struct super_block *sb, int type, int remount) toputinode[cnt] = NULL; if (type != -1 && cnt != type) continue; - /* If we keep inodes of quota files after remount and quotaoff - * is called, drop kept inodes. */ - if (!remount && sb_has_quota_suspended(sb, cnt)) { - iput(dqopt->files[cnt]); - dqopt->files[cnt] = NULL; - reset_enable_flags(dqopt, cnt, 0); + if (!sb_has_quota_loaded(sb, cnt)) continue; + + if (flags & DQUOT_SUSPENDED) { + spin_lock(&dq_state_lock); + dqopt->flags |= + dquot_state_flag(DQUOT_SUSPENDED, cnt); + spin_unlock(&dq_state_lock); + } else { + spin_lock(&dq_state_lock); + dqopt->flags &= ~dquot_state_flag(flags, cnt); + /* Turning off suspended quotas? */ + if (!sb_has_quota_loaded(sb, cnt) && + sb_has_quota_suspended(sb, cnt)) { + dqopt->flags &= ~dquot_state_flag( + DQUOT_SUSPENDED, cnt); + spin_unlock(&dq_state_lock); + iput(dqopt->files[cnt]); + dqopt->files[cnt] = NULL; + continue; + } + spin_unlock(&dq_state_lock); } - if (!sb_has_quota_enabled(sb, cnt)) + + /* We still have to keep quota loaded? */ + if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED)) continue; - reset_enable_flags(dqopt, cnt, remount); /* Note: these are blocking operations */ drop_dquot_ref(sb, cnt); @@ -1623,7 +1710,7 @@ int vfs_quota_off(struct super_block *sb, int type, int remount) put_quota_format(dqopt->info[cnt].dqi_format); toputinode[cnt] = dqopt->files[cnt]; - if (!remount) + if (!sb_has_quota_loaded(sb, cnt)) dqopt->files[cnt] = NULL; dqopt->info[cnt].dqi_flags = 0; dqopt->info[cnt].dqi_igrace = 0; @@ -1631,6 +1718,11 @@ int vfs_quota_off(struct super_block *sb, int type, int remount) dqopt->ops[cnt] = NULL; } mutex_unlock(&dqopt->dqonoff_mutex); + + /* Skip syncing and setting flags if quota files are hidden */ + if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) + goto put_inodes; + /* Sync the superblock so that buffers with quota data are written to * disk (and so userspace sees correct data afterwards). */ if (sb->s_op->sync_fs) @@ -1646,7 +1738,7 @@ int vfs_quota_off(struct super_block *sb, int type, int remount) mutex_lock(&dqopt->dqonoff_mutex); /* If quota was reenabled in the meantime, we have * nothing to do */ - if (!sb_has_quota_enabled(sb, cnt)) { + if (!sb_has_quota_loaded(sb, cnt)) { mutex_lock_nested(&toputinode[cnt]->i_mutex, I_MUTEX_QUOTA); toputinode[cnt]->i_flags &= ~(S_IMMUTABLE | S_NOATIME | S_NOQUOTA); @@ -1655,26 +1747,43 @@ int vfs_quota_off(struct super_block *sb, int type, int remount) mark_inode_dirty(toputinode[cnt]); } mutex_unlock(&dqopt->dqonoff_mutex); + } + if (sb->s_bdev) + invalidate_bdev(sb->s_bdev); +put_inodes: + for (cnt = 0; cnt < MAXQUOTAS; cnt++) + if (toputinode[cnt]) { /* On remount RO, we keep the inode pointer so that we - * can reenable quota on the subsequent remount RW. - * But we have better not keep inode pointer when there - * is pending delete on the quota file... */ - if (!remount) + * can reenable quota on the subsequent remount RW. We + * have to check 'flags' variable and not use sb_has_ + * function because another quotaon / quotaoff could + * change global state before we got here. We refuse + * to suspend quotas when there is pending delete on + * the quota file... */ + if (!(flags & DQUOT_SUSPENDED)) iput(toputinode[cnt]); else if (!toputinode[cnt]->i_nlink) ret = -EBUSY; } - if (sb->s_bdev) - invalidate_bdev(sb->s_bdev); return ret; } +int vfs_quota_off(struct super_block *sb, int type, int remount) +{ + return vfs_quota_disable(sb, type, remount ? DQUOT_SUSPENDED : + (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED)); +} + /* * Turn quotas on on a device */ -/* Helper function when we already have the inode */ -static int vfs_quota_on_inode(struct inode *inode, int type, int format_id) +/* + * Helper function to turn quotas on when we already have the inode of + * quota file and no quota information is loaded. + */ +static int vfs_load_quota_inode(struct inode *inode, int type, int format_id, + unsigned int flags) { struct quota_format_type *fmt = find_quota_format(format_id); struct super_block *sb = inode->i_sb; @@ -1696,27 +1805,37 @@ static int vfs_quota_on_inode(struct inode *inode, int type, int format_id) error = -EINVAL; goto out_fmt; } + /* Usage always has to be set... */ + if (!(flags & DQUOT_USAGE_ENABLED)) { + error = -EINVAL; + goto out_fmt; + } - /* As we bypass the pagecache we must now flush the inode so that - * we see all the changes from userspace... */ - write_inode_now(inode, 1); - /* And now flush the block cache so that kernel sees the changes */ - invalidate_bdev(sb->s_bdev); + if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { + /* As we bypass the pagecache we must now flush the inode so + * that we see all the changes from userspace... */ + write_inode_now(inode, 1); + /* And now flush the block cache so that kernel sees the + * changes */ + invalidate_bdev(sb->s_bdev); + } mutex_lock(&inode->i_mutex); mutex_lock(&dqopt->dqonoff_mutex); - if (sb_has_quota_enabled(sb, type) || - sb_has_quota_suspended(sb, type)) { + if (sb_has_quota_loaded(sb, type)) { error = -EBUSY; goto out_lock; } - /* We don't want quota and atime on quota files (deadlocks possible) - * Also nobody should write to the file - we use special IO operations - * which ignore the immutable bit. */ - down_write(&dqopt->dqptr_sem); - oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | S_NOQUOTA); - inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; - up_write(&dqopt->dqptr_sem); - sb->dq_op->drop(inode); + + if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) { + /* We don't want quota and atime on quota files (deadlocks + * possible) Also nobody should write to the file - we use + * special IO operations which ignore the immutable bit. */ + down_write(&dqopt->dqptr_sem); + oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | S_NOQUOTA); + inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE; + up_write(&dqopt->dqptr_sem); + sb->dq_op->drop(inode); + } error = -EIO; dqopt->files[type] = igrab(inode); @@ -1737,7 +1856,9 @@ static int vfs_quota_on_inode(struct inode *inode, int type, int format_id) } mutex_unlock(&dqopt->dqio_mutex); mutex_unlock(&inode->i_mutex); - set_enable_flags(dqopt, type); + spin_lock(&dq_state_lock); + dqopt->flags |= dquot_state_flag(flags, type); + spin_unlock(&dq_state_lock); add_dquot_ref(sb, type); mutex_unlock(&dqopt->dqonoff_mutex); @@ -1770,20 +1891,25 @@ static int vfs_quota_on_remount(struct super_block *sb, int type) struct quota_info *dqopt = sb_dqopt(sb); struct inode *inode; int ret; + unsigned int flags; mutex_lock(&dqopt->dqonoff_mutex); if (!sb_has_quota_suspended(sb, type)) { mutex_unlock(&dqopt->dqonoff_mutex); return 0; } - BUG_ON(sb_has_quota_enabled(sb, type)); - inode = dqopt->files[type]; dqopt->files[type] = NULL; - reset_enable_flags(dqopt, type, 0); + spin_lock(&dq_state_lock); + flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED | + DQUOT_LIMITS_ENABLED, type); + dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, type); + spin_unlock(&dq_state_lock); mutex_unlock(&dqopt->dqonoff_mutex); - ret = vfs_quota_on_inode(inode, type, dqopt->info[type].dqi_fmt_id); + flags = dquot_generic_flag(flags, type); + ret = vfs_load_quota_inode(inode, type, dqopt->info[type].dqi_fmt_id, + flags); iput(inode); return ret; @@ -1799,12 +1925,12 @@ int vfs_quota_on_path(struct super_block *sb, int type, int format_id, if (path->mnt->mnt_sb != sb) error = -EXDEV; else - error = vfs_quota_on_inode(path->dentry->d_inode, type, - format_id); + error = vfs_load_quota_inode(path->dentry->d_inode, type, + format_id, DQUOT_USAGE_ENABLED | + DQUOT_LIMITS_ENABLED); return error; } -/* Actual function called from quotactl() */ int vfs_quota_on(struct super_block *sb, int type, int format_id, char *name, int remount) { @@ -1823,6 +1949,52 @@ int vfs_quota_on(struct super_block *sb, int type, int format_id, char *name, } /* + * More powerful function for turning on quotas allowing setting + * of individual quota flags + */ +int vfs_quota_enable(struct inode *inode, int type, int format_id, + unsigned int flags) +{ + int ret = 0; + struct super_block *sb = inode->i_sb; + struct quota_info *dqopt = sb_dqopt(sb); + + /* Just unsuspend quotas? */ + if (flags & DQUOT_SUSPENDED) + return vfs_quota_on_remount(sb, type); + if (!flags) + return 0; + /* Just updating flags needed? */ + if (sb_has_quota_loaded(sb, type)) { + mutex_lock(&dqopt->dqonoff_mutex); + /* Now do a reliable test... */ + if (!sb_has_quota_loaded(sb, type)) { + mutex_unlock(&dqopt->dqonoff_mutex); + goto load_quota; + } + if (flags & DQUOT_USAGE_ENABLED && + sb_has_quota_usage_enabled(sb, type)) { + ret = -EBUSY; + goto out_lock; + } + if (flags & DQUOT_LIMITS_ENABLED && + sb_has_quota_limits_enabled(sb, type)) { + ret = -EBUSY; + goto out_lock; + } + spin_lock(&dq_state_lock); + sb_dqopt(sb)->flags |= dquot_state_flag(flags, type); + spin_unlock(&dq_state_lock); +out_lock: + mutex_unlock(&dqopt->dqonoff_mutex); + return ret; + } + +load_quota: + return vfs_load_quota_inode(inode, type, format_id, flags); +} + +/* * This function is used when filesystem needs to initialize quotas * during mount time. */ @@ -1843,7 +2015,8 @@ int vfs_quota_on_mount(struct super_block *sb, char *qf_name, error = security_quota_on(dentry); if (!error) - error = vfs_quota_on_inode(dentry->d_inode, type, format_id); + error = vfs_load_quota_inode(dentry->d_inode, type, format_id, + DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED); out: dput(dentry); @@ -1866,14 +2039,24 @@ int vfs_dq_quota_on_remount(struct super_block *sb) return ret; } +static inline qsize_t qbtos(qsize_t blocks) +{ + return blocks << QIF_DQBLKSIZE_BITS; +} + +static inline qsize_t stoqb(qsize_t space) +{ + return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS; +} + /* Generic routine for getting common part of quota structure */ static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di) { struct mem_dqblk *dm = &dquot->dq_dqb; spin_lock(&dq_data_lock); - di->dqb_bhardlimit = dm->dqb_bhardlimit; - di->dqb_bsoftlimit = dm->dqb_bsoftlimit; + di->dqb_bhardlimit = stoqb(dm->dqb_bhardlimit); + di->dqb_bsoftlimit = stoqb(dm->dqb_bsoftlimit); di->dqb_curspace = dm->dqb_curspace; di->dqb_ihardlimit = dm->dqb_ihardlimit; di->dqb_isoftlimit = dm->dqb_isoftlimit; @@ -1888,14 +2071,12 @@ int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *d { struct dquot *dquot; - mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); - if (!(dquot = dqget(sb, id, type))) { - mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); + dquot = dqget(sb, id, type); + if (dquot == NODQUOT) return -ESRCH; - } do_get_dqblk(dquot, di); dqput(dquot); - mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); + return 0; } @@ -1918,28 +2099,38 @@ static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di) if (di->dqb_valid & QIF_SPACE) { dm->dqb_curspace = di->dqb_curspace; check_blim = 1; + __set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags); } if (di->dqb_valid & QIF_BLIMITS) { - dm->dqb_bsoftlimit = di->dqb_bsoftlimit; - dm->dqb_bhardlimit = di->dqb_bhardlimit; + dm->dqb_bsoftlimit = qbtos(di->dqb_bsoftlimit); + dm->dqb_bhardlimit = qbtos(di->dqb_bhardlimit); check_blim = 1; + __set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags); } if (di->dqb_valid & QIF_INODES) { dm->dqb_curinodes = di->dqb_curinodes; check_ilim = 1; + __set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags); } if (di->dqb_valid & QIF_ILIMITS) { dm->dqb_isoftlimit = di->dqb_isoftlimit; dm->dqb_ihardlimit = di->dqb_ihardlimit; check_ilim = 1; + __set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags); } - if (di->dqb_valid & QIF_BTIME) + if (di->dqb_valid & QIF_BTIME) { dm->dqb_btime = di->dqb_btime; - if (di->dqb_valid & QIF_ITIME) + check_blim = 1; + __set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags); + } + if (di->dqb_valid & QIF_ITIME) { dm->dqb_itime = di->dqb_itime; + check_ilim = 1; + __set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags); + } if (check_blim) { - if (!dm->dqb_bsoftlimit || toqb(dm->dqb_curspace) < dm->dqb_bsoftlimit) { + if (!dm->dqb_bsoftlimit || dm->dqb_curspace < dm->dqb_bsoftlimit) { dm->dqb_btime = 0; clear_bit(DQ_BLKS_B, &dquot->dq_flags); } @@ -1969,14 +2160,14 @@ int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *d struct dquot *dquot; int rc; - mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); - if (!(dquot = dqget(sb, id, type))) { - mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); - return -ESRCH; + dquot = dqget(sb, id, type); + if (!dquot) { + rc = -ESRCH; + goto out; } rc = do_set_dqblk(dquot, di); dqput(dquot); - mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); +out: return rc; } @@ -1986,7 +2177,7 @@ int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) struct mem_dqinfo *mi; mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); - if (!sb_has_quota_enabled(sb, type)) { + if (!sb_has_quota_active(sb, type)) { mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); return -ESRCH; } @@ -2005,11 +2196,12 @@ int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) { struct mem_dqinfo *mi; + int err = 0; mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); - if (!sb_has_quota_enabled(sb, type)) { - mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); - return -ESRCH; + if (!sb_has_quota_active(sb, type)) { + err = -ESRCH; + goto out; } mi = sb_dqopt(sb)->info + type; spin_lock(&dq_data_lock); @@ -2023,8 +2215,9 @@ int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii) mark_info_dirty(sb, type); /* Force write to disk */ sb->dq_op->write_info(sb, type); +out: mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); - return 0; + return err; } struct quotactl_ops vfs_quotactl_ops = { @@ -2186,10 +2379,13 @@ EXPORT_SYMBOL(register_quota_format); EXPORT_SYMBOL(unregister_quota_format); EXPORT_SYMBOL(dqstats); EXPORT_SYMBOL(dq_data_lock); +EXPORT_SYMBOL(vfs_quota_enable); EXPORT_SYMBOL(vfs_quota_on); EXPORT_SYMBOL(vfs_quota_on_path); EXPORT_SYMBOL(vfs_quota_on_mount); +EXPORT_SYMBOL(vfs_quota_disable); EXPORT_SYMBOL(vfs_quota_off); +EXPORT_SYMBOL(dquot_scan_active); EXPORT_SYMBOL(vfs_quota_sync); EXPORT_SYMBOL(vfs_get_dqinfo); EXPORT_SYMBOL(vfs_set_dqinfo); @@ -2203,6 +2399,8 @@ EXPORT_SYMBOL(dquot_mark_dquot_dirty); EXPORT_SYMBOL(dquot_initialize); EXPORT_SYMBOL(dquot_drop); EXPORT_SYMBOL(vfs_dq_drop); +EXPORT_SYMBOL(dqget); +EXPORT_SYMBOL(dqput); EXPORT_SYMBOL(dquot_alloc_space); EXPORT_SYMBOL(dquot_alloc_inode); EXPORT_SYMBOL(dquot_free_space); |