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Diffstat (limited to 'fs/quota/dquot.c')
-rw-r--r--fs/quota/dquot.c289
1 files changed, 139 insertions, 150 deletions
diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index 6e826b454082..4639d53e96a3 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -497,7 +497,7 @@ int dquot_release(struct dquot *dquot)
mutex_lock(&dquot->dq_lock);
/* Check whether we are not racing with some other dqget() */
- if (atomic_read(&dquot->dq_count) > 1)
+ if (dquot_is_busy(dquot))
goto out_dqlock;
if (dqopt->ops[dquot->dq_id.type]->release_dqblk) {
ret = dqopt->ops[dquot->dq_id.type]->release_dqblk(dquot);
@@ -595,7 +595,6 @@ int dquot_scan_active(struct super_block *sb,
/* Now we have active dquot so we can just increase use count */
atomic_inc(&dquot->dq_count);
spin_unlock(&dq_list_lock);
- dqstats_inc(DQST_LOOKUPS);
dqput(old_dquot);
old_dquot = dquot;
/*
@@ -623,7 +622,7 @@ EXPORT_SYMBOL(dquot_scan_active);
/* Write all dquot structures to quota files */
int dquot_writeback_dquots(struct super_block *sb, int type)
{
- struct list_head *dirty;
+ struct list_head dirty;
struct dquot *dquot;
struct quota_info *dqopt = sb_dqopt(sb);
int cnt;
@@ -637,9 +636,10 @@ int dquot_writeback_dquots(struct super_block *sb, int type)
if (!sb_has_quota_active(sb, cnt))
continue;
spin_lock(&dq_list_lock);
- dirty = &dqopt->info[cnt].dqi_dirty_list;
- while (!list_empty(dirty)) {
- dquot = list_first_entry(dirty, struct dquot,
+ /* Move list away to avoid livelock. */
+ list_replace_init(&dqopt->info[cnt].dqi_dirty_list, &dirty);
+ while (!list_empty(&dirty)) {
+ dquot = list_first_entry(&dirty, struct dquot,
dq_dirty);
WARN_ON(!test_bit(DQ_ACTIVE_B, &dquot->dq_flags));
@@ -649,7 +649,6 @@ int dquot_writeback_dquots(struct super_block *sb, int type)
* use count */
dqgrab(dquot);
spin_unlock(&dq_list_lock);
- dqstats_inc(DQST_LOOKUPS);
err = sb->dq_op->write_dquot(dquot);
if (err) {
/*
@@ -2162,14 +2161,29 @@ int dquot_file_open(struct inode *inode, struct file *file)
}
EXPORT_SYMBOL(dquot_file_open);
+static void vfs_cleanup_quota_inode(struct super_block *sb, int type)
+{
+ struct quota_info *dqopt = sb_dqopt(sb);
+ struct inode *inode = dqopt->files[type];
+
+ if (!inode)
+ return;
+ if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
+ inode_lock(inode);
+ inode->i_flags &= ~S_NOQUOTA;
+ inode_unlock(inode);
+ }
+ dqopt->files[type] = NULL;
+ iput(inode);
+}
+
/*
* Turn quota off on a device. type == -1 ==> quotaoff for all types (umount)
*/
int dquot_disable(struct super_block *sb, int type, unsigned int flags)
{
- int cnt, ret = 0;
+ int cnt;
struct quota_info *dqopt = sb_dqopt(sb);
- struct inode *toputinode[MAXQUOTAS];
/* s_umount should be held in exclusive mode */
if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount)))
@@ -2191,7 +2205,6 @@ int dquot_disable(struct super_block *sb, int type, unsigned int flags)
return 0;
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
- toputinode[cnt] = NULL;
if (type != -1 && cnt != type)
continue;
if (!sb_has_quota_loaded(sb, cnt))
@@ -2211,8 +2224,7 @@ int dquot_disable(struct super_block *sb, int type, unsigned int flags)
dqopt->flags &= ~dquot_state_flag(
DQUOT_SUSPENDED, cnt);
spin_unlock(&dq_state_lock);
- iput(dqopt->files[cnt]);
- dqopt->files[cnt] = NULL;
+ vfs_cleanup_quota_inode(sb, cnt);
continue;
}
spin_unlock(&dq_state_lock);
@@ -2234,10 +2246,6 @@ int dquot_disable(struct super_block *sb, int type, unsigned int flags)
if (dqopt->ops[cnt]->free_file_info)
dqopt->ops[cnt]->free_file_info(sb, cnt);
put_quota_format(dqopt->info[cnt].dqi_format);
-
- toputinode[cnt] = dqopt->files[cnt];
- if (!sb_has_quota_loaded(sb, cnt))
- dqopt->files[cnt] = NULL;
dqopt->info[cnt].dqi_flags = 0;
dqopt->info[cnt].dqi_igrace = 0;
dqopt->info[cnt].dqi_bgrace = 0;
@@ -2259,32 +2267,22 @@ int dquot_disable(struct super_block *sb, int type, unsigned int flags)
* must also discard the blockdev buffers so that we see the
* changes done by userspace on the next quotaon() */
for (cnt = 0; cnt < MAXQUOTAS; cnt++)
- /* This can happen when suspending quotas on remount-ro... */
- if (toputinode[cnt] && !sb_has_quota_loaded(sb, cnt)) {
- inode_lock(toputinode[cnt]);
- toputinode[cnt]->i_flags &= ~S_NOQUOTA;
- truncate_inode_pages(&toputinode[cnt]->i_data, 0);
- inode_unlock(toputinode[cnt]);
- mark_inode_dirty_sync(toputinode[cnt]);
+ if (!sb_has_quota_loaded(sb, cnt) && dqopt->files[cnt]) {
+ inode_lock(dqopt->files[cnt]);
+ truncate_inode_pages(&dqopt->files[cnt]->i_data, 0);
+ inode_unlock(dqopt->files[cnt]);
}
if (sb->s_bdev)
invalidate_bdev(sb->s_bdev);
put_inodes:
+ /* We are done when suspending quotas */
+ if (flags & DQUOT_SUSPENDED)
+ return 0;
+
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. 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;
- }
- return ret;
+ if (!sb_has_quota_loaded(sb, cnt))
+ vfs_cleanup_quota_inode(sb, cnt);
+ return 0;
}
EXPORT_SYMBOL(dquot_disable);
@@ -2299,28 +2297,52 @@ EXPORT_SYMBOL(dquot_quota_off);
* Turn quotas on on a device
*/
-/*
- * 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,
+static int vfs_setup_quota_inode(struct inode *inode, int type)
+{
+ struct super_block *sb = inode->i_sb;
+ struct quota_info *dqopt = sb_dqopt(sb);
+
+ if (!S_ISREG(inode->i_mode))
+ return -EACCES;
+ if (IS_RDONLY(inode))
+ return -EROFS;
+ if (sb_has_quota_loaded(sb, type))
+ return -EBUSY;
+
+ dqopt->files[type] = igrab(inode);
+ if (!dqopt->files[type])
+ return -EIO;
+ 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. */
+ inode_lock(inode);
+ inode->i_flags |= S_NOQUOTA;
+ inode_unlock(inode);
+ /*
+ * When S_NOQUOTA is set, remove dquot references as no more
+ * references can be added
+ */
+ __dquot_drop(inode);
+ }
+ return 0;
+}
+
+int dquot_load_quota_sb(struct super_block *sb, 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;
struct quota_info *dqopt = sb_dqopt(sb);
int error;
+ /* Just unsuspend quotas? */
+ BUG_ON(flags & DQUOT_SUSPENDED);
+ /* s_umount should be held in exclusive mode */
+ if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount)))
+ up_read(&sb->s_umount);
+
if (!fmt)
return -ESRCH;
- if (!S_ISREG(inode->i_mode)) {
- error = -EACCES;
- goto out_fmt;
- }
- if (IS_RDONLY(inode)) {
- error = -EROFS;
- goto out_fmt;
- }
if (!sb->s_op->quota_write || !sb->s_op->quota_read ||
(type == PRJQUOTA && sb->dq_op->get_projid == NULL)) {
error = -EINVAL;
@@ -2352,27 +2374,9 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
invalidate_bdev(sb->s_bdev);
}
- 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. */
- inode_lock(inode);
- inode->i_flags |= S_NOQUOTA;
- inode_unlock(inode);
- /*
- * When S_NOQUOTA is set, remove dquot references as no more
- * references can be added
- */
- __dquot_drop(inode);
- }
-
- error = -EIO;
- dqopt->files[type] = igrab(inode);
- if (!dqopt->files[type])
- goto out_file_flags;
error = -EINVAL;
if (!fmt->qf_ops->check_quota_file(sb, type))
- goto out_file_init;
+ goto out_fmt;
dqopt->ops[type] = fmt->qf_ops;
dqopt->info[type].dqi_format = fmt;
@@ -2380,7 +2384,7 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list);
error = dqopt->ops[type]->read_file_info(sb, type);
if (error < 0)
- goto out_file_init;
+ goto out_fmt;
if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) {
spin_lock(&dq_data_lock);
dqopt->info[type].dqi_flags |= DQF_SYS_FILE;
@@ -2395,24 +2399,36 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
dquot_disable(sb, type, flags);
return error;
-out_file_init:
- dqopt->files[type] = NULL;
- iput(inode);
-out_file_flags:
- inode_lock(inode);
- inode->i_flags &= ~S_NOQUOTA;
- inode_unlock(inode);
out_fmt:
put_quota_format(fmt);
return error;
}
+EXPORT_SYMBOL(dquot_load_quota_sb);
+
+/*
+ * More powerful function for turning on quotas on given quota inode allowing
+ * setting of individual quota flags
+ */
+int dquot_load_quota_inode(struct inode *inode, int type, int format_id,
+ unsigned int flags)
+{
+ int err;
+
+ err = vfs_setup_quota_inode(inode, type);
+ if (err < 0)
+ return err;
+ err = dquot_load_quota_sb(inode->i_sb, type, format_id, flags);
+ if (err < 0)
+ vfs_cleanup_quota_inode(inode->i_sb, type);
+ return err;
+}
+EXPORT_SYMBOL(dquot_load_quota_inode);
/* Reenable quotas on remount RW */
int dquot_resume(struct super_block *sb, int type)
{
struct quota_info *dqopt = sb_dqopt(sb);
- struct inode *inode;
int ret = 0, cnt;
unsigned int flags;
@@ -2426,8 +2442,6 @@ int dquot_resume(struct super_block *sb, int type)
if (!sb_has_quota_suspended(sb, cnt))
continue;
- inode = dqopt->files[cnt];
- dqopt->files[cnt] = NULL;
spin_lock(&dq_state_lock);
flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED |
DQUOT_LIMITS_ENABLED,
@@ -2436,9 +2450,10 @@ int dquot_resume(struct super_block *sb, int type)
spin_unlock(&dq_state_lock);
flags = dquot_generic_flag(flags, cnt);
- ret = vfs_load_quota_inode(inode, cnt,
- dqopt->info[cnt].dqi_fmt_id, flags);
- iput(inode);
+ ret = dquot_load_quota_sb(sb, cnt, dqopt->info[cnt].dqi_fmt_id,
+ flags);
+ if (ret < 0)
+ vfs_cleanup_quota_inode(sb, type);
}
return ret;
@@ -2455,7 +2470,7 @@ int dquot_quota_on(struct super_block *sb, int type, int format_id,
if (path->dentry->d_sb != sb)
error = -EXDEV;
else
- error = vfs_load_quota_inode(d_inode(path->dentry), type,
+ error = dquot_load_quota_inode(d_inode(path->dentry), type,
format_id, DQUOT_USAGE_ENABLED |
DQUOT_LIMITS_ENABLED);
return error;
@@ -2463,41 +2478,6 @@ int dquot_quota_on(struct super_block *sb, int type, int format_id,
EXPORT_SYMBOL(dquot_quota_on);
/*
- * More powerful function for turning on quotas allowing setting
- * of individual quota flags
- */
-int dquot_enable(struct inode *inode, int type, int format_id,
- unsigned int flags)
-{
- struct super_block *sb = inode->i_sb;
-
- /* Just unsuspend quotas? */
- BUG_ON(flags & DQUOT_SUSPENDED);
- /* s_umount should be held in exclusive mode */
- if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount)))
- up_read(&sb->s_umount);
-
- if (!flags)
- return 0;
- /* Just updating flags needed? */
- if (sb_has_quota_loaded(sb, type)) {
- if (flags & DQUOT_USAGE_ENABLED &&
- sb_has_quota_usage_enabled(sb, type))
- return -EBUSY;
- if (flags & DQUOT_LIMITS_ENABLED &&
- sb_has_quota_limits_enabled(sb, type))
- return -EBUSY;
- spin_lock(&dq_state_lock);
- sb_dqopt(sb)->flags |= dquot_state_flag(flags, type);
- spin_unlock(&dq_state_lock);
- return 0;
- }
-
- return vfs_load_quota_inode(inode, type, format_id, flags);
-}
-EXPORT_SYMBOL(dquot_enable);
-
-/*
* This function is used when filesystem needs to initialize quotas
* during mount time.
*/
@@ -2518,7 +2498,7 @@ int dquot_quota_on_mount(struct super_block *sb, char *qf_name,
error = security_quota_on(dentry);
if (!error)
- error = vfs_load_quota_inode(d_inode(dentry), type, format_id,
+ error = dquot_load_quota_inode(d_inode(dentry), type, format_id,
DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
out:
@@ -2543,13 +2523,17 @@ static int dquot_quota_enable(struct super_block *sb, unsigned int flags)
if (!(flags & qtype_enforce_flag(type)))
continue;
/* Can't enforce without accounting */
- if (!sb_has_quota_usage_enabled(sb, type))
- return -EINVAL;
- ret = dquot_enable(dqopt->files[type], type,
- dqopt->info[type].dqi_fmt_id,
- DQUOT_LIMITS_ENABLED);
- if (ret < 0)
+ if (!sb_has_quota_usage_enabled(sb, type)) {
+ ret = -EINVAL;
goto out_err;
+ }
+ if (sb_has_quota_limits_enabled(sb, type)) {
+ ret = -EBUSY;
+ goto out_err;
+ }
+ spin_lock(&dq_state_lock);
+ dqopt->flags |= dquot_state_flag(DQUOT_LIMITS_ENABLED, type);
+ spin_unlock(&dq_state_lock);
}
return 0;
out_err:
@@ -2599,10 +2583,12 @@ static int dquot_quota_disable(struct super_block *sb, unsigned int flags)
out_err:
/* Backout enforcement disabling we already did */
for (type--; type >= 0; type--) {
- if (flags & qtype_enforce_flag(type))
- dquot_enable(dqopt->files[type], type,
- dqopt->info[type].dqi_fmt_id,
- DQUOT_LIMITS_ENABLED);
+ if (flags & qtype_enforce_flag(type)) {
+ spin_lock(&dq_state_lock);
+ dqopt->flags |=
+ dquot_state_flag(DQUOT_LIMITS_ENABLED, type);
+ spin_unlock(&dq_state_lock);
+ }
}
return ret;
}
@@ -2800,8 +2786,10 @@ int dquot_get_state(struct super_block *sb, struct qc_state *state)
tstate->flags |= QCI_LIMITS_ENFORCED;
tstate->spc_timelimit = mi->dqi_bgrace;
tstate->ino_timelimit = mi->dqi_igrace;
- tstate->ino = dqopt->files[type]->i_ino;
- tstate->blocks = dqopt->files[type]->i_blocks;
+ if (dqopt->files[type]) {
+ tstate->ino = dqopt->files[type]->i_ino;
+ tstate->blocks = dqopt->files[type]->i_blocks;
+ }
tstate->nextents = 1; /* We don't know... */
spin_unlock(&dq_data_lock);
}
@@ -2860,68 +2848,73 @@ EXPORT_SYMBOL(dquot_quotactl_sysfile_ops);
static int do_proc_dqstats(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
- unsigned int type = (int *)table->data - dqstats.stat;
+ unsigned int type = (unsigned long *)table->data - dqstats.stat;
+ s64 value = percpu_counter_sum(&dqstats.counter[type]);
+
+ /* Filter negative values for non-monotonic counters */
+ if (value < 0 && (type == DQST_ALLOC_DQUOTS ||
+ type == DQST_FREE_DQUOTS))
+ value = 0;
/* Update global table */
- dqstats.stat[type] =
- percpu_counter_sum_positive(&dqstats.counter[type]);
- return proc_dointvec(table, write, buffer, lenp, ppos);
+ dqstats.stat[type] = value;
+ return proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
}
static struct ctl_table fs_dqstats_table[] = {
{
.procname = "lookups",
.data = &dqstats.stat[DQST_LOOKUPS],
- .maxlen = sizeof(int),
+ .maxlen = sizeof(unsigned long),
.mode = 0444,
.proc_handler = do_proc_dqstats,
},
{
.procname = "drops",
.data = &dqstats.stat[DQST_DROPS],
- .maxlen = sizeof(int),
+ .maxlen = sizeof(unsigned long),
.mode = 0444,
.proc_handler = do_proc_dqstats,
},
{
.procname = "reads",
.data = &dqstats.stat[DQST_READS],
- .maxlen = sizeof(int),
+ .maxlen = sizeof(unsigned long),
.mode = 0444,
.proc_handler = do_proc_dqstats,
},
{
.procname = "writes",
.data = &dqstats.stat[DQST_WRITES],
- .maxlen = sizeof(int),
+ .maxlen = sizeof(unsigned long),
.mode = 0444,
.proc_handler = do_proc_dqstats,
},
{
.procname = "cache_hits",
.data = &dqstats.stat[DQST_CACHE_HITS],
- .maxlen = sizeof(int),
+ .maxlen = sizeof(unsigned long),
.mode = 0444,
.proc_handler = do_proc_dqstats,
},
{
.procname = "allocated_dquots",
.data = &dqstats.stat[DQST_ALLOC_DQUOTS],
- .maxlen = sizeof(int),
+ .maxlen = sizeof(unsigned long),
.mode = 0444,
.proc_handler = do_proc_dqstats,
},
{
.procname = "free_dquots",
.data = &dqstats.stat[DQST_FREE_DQUOTS],
- .maxlen = sizeof(int),
+ .maxlen = sizeof(unsigned long),
.mode = 0444,
.proc_handler = do_proc_dqstats,
},
{
.procname = "syncs",
.data = &dqstats.stat[DQST_SYNCS],
- .maxlen = sizeof(int),
+ .maxlen = sizeof(unsigned long),
.mode = 0444,
.proc_handler = do_proc_dqstats,
},
@@ -2983,11 +2976,7 @@ static int __init dquot_init(void)
/* Find power-of-two hlist_heads which can fit into allocation */
nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head);
- dq_hash_bits = 0;
- do {
- dq_hash_bits++;
- } while (nr_hash >> dq_hash_bits);
- dq_hash_bits--;
+ dq_hash_bits = ilog2(nr_hash);
nr_hash = 1UL << dq_hash_bits;
dq_hash_mask = nr_hash - 1;