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-rw-r--r--fs/quota/dquot.c226
1 files changed, 101 insertions, 125 deletions
diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index 4bb4b4b79..6a7b7d447 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -401,15 +401,17 @@ int dquot_mark_dquot_dirty(struct dquot *dquot)
EXPORT_SYMBOL(dquot_mark_dquot_dirty);
/* Dirtify all the dquots - this can block when journalling */
-static inline int mark_all_dquot_dirty(struct dquot * const *dquot)
+static inline int mark_all_dquot_dirty(struct dquot __rcu * const *dquots)
{
int ret, err, cnt;
+ struct dquot *dquot;
ret = err = 0;
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
- if (dquot[cnt])
+ dquot = srcu_dereference(dquots[cnt], &dquot_srcu);
+ if (dquot)
/* Even in case of error we have to continue */
- ret = mark_dquot_dirty(dquot[cnt]);
+ ret = mark_dquot_dirty(dquot);
if (!err)
err = ret;
}
@@ -1006,14 +1008,15 @@ out:
}
EXPORT_SYMBOL(dqget);
-static inline struct dquot **i_dquot(struct inode *inode)
+static inline struct dquot __rcu **i_dquot(struct inode *inode)
{
- return inode->i_sb->s_op->get_dquots(inode);
+ /* Force __rcu for now until filesystems are fixed */
+ return (struct dquot __rcu **)inode->i_sb->s_op->get_dquots(inode);
}
static int dqinit_needed(struct inode *inode, int type)
{
- struct dquot * const *dquots;
+ struct dquot __rcu * const *dquots;
int cnt;
if (IS_NOQUOTA(inode))
@@ -1086,59 +1089,7 @@ out:
return err;
}
-/*
- * Remove references to dquots from inode and add dquot to list for freeing
- * if we have the last reference to dquot
- */
-static void remove_inode_dquot_ref(struct inode *inode, int type,
- struct list_head *tofree_head)
-{
- struct dquot **dquots = i_dquot(inode);
- struct dquot *dquot = dquots[type];
-
- if (!dquot)
- return;
-
- dquots[type] = NULL;
- if (list_empty(&dquot->dq_free)) {
- /*
- * The inode still has reference to dquot so it can't be in the
- * free list
- */
- spin_lock(&dq_list_lock);
- list_add(&dquot->dq_free, tofree_head);
- spin_unlock(&dq_list_lock);
- } else {
- /*
- * Dquot is already in a list to put so we won't drop the last
- * reference here.
- */
- dqput(dquot);
- }
-}
-
-/*
- * Free list of dquots
- * Dquots are removed from inodes and no new references can be got so we are
- * the only ones holding reference
- */
-static void put_dquot_list(struct list_head *tofree_head)
-{
- struct list_head *act_head;
- struct dquot *dquot;
-
- act_head = tofree_head->next;
- while (act_head != tofree_head) {
- dquot = list_entry(act_head, struct dquot, dq_free);
- act_head = act_head->next;
- /* Remove dquot from the list so we won't have problems... */
- list_del_init(&dquot->dq_free);
- dqput(dquot);
- }
-}
-
-static void remove_dquot_ref(struct super_block *sb, int type,
- struct list_head *tofree_head)
+static void remove_dquot_ref(struct super_block *sb, int type)
{
struct inode *inode;
#ifdef CONFIG_QUOTA_DEBUG
@@ -1155,11 +1106,18 @@ static void remove_dquot_ref(struct super_block *sb, int type,
*/
spin_lock(&dq_data_lock);
if (!IS_NOQUOTA(inode)) {
+ struct dquot __rcu **dquots = i_dquot(inode);
+ struct dquot *dquot = srcu_dereference_check(
+ dquots[type], &dquot_srcu,
+ lockdep_is_held(&dq_data_lock));
+
#ifdef CONFIG_QUOTA_DEBUG
if (unlikely(inode_get_rsv_space(inode) > 0))
reserved = 1;
#endif
- remove_inode_dquot_ref(inode, type, tofree_head);
+ rcu_assign_pointer(dquots[type], NULL);
+ if (dquot)
+ dqput(dquot);
}
spin_unlock(&dq_data_lock);
}
@@ -1176,13 +1134,8 @@ static void remove_dquot_ref(struct super_block *sb, int type,
/* Gather all references from inodes and drop them */
static void drop_dquot_ref(struct super_block *sb, int type)
{
- LIST_HEAD(tofree_head);
-
- if (sb->dq_op) {
- remove_dquot_ref(sb, type, &tofree_head);
- synchronize_srcu(&dquot_srcu);
- put_dquot_list(&tofree_head);
- }
+ if (sb->dq_op)
+ remove_dquot_ref(sb, type);
}
static inline
@@ -1515,7 +1468,8 @@ static int inode_quota_active(const struct inode *inode)
static int __dquot_initialize(struct inode *inode, int type)
{
int cnt, init_needed = 0;
- struct dquot **dquots, *got[MAXQUOTAS] = {};
+ struct dquot __rcu **dquots;
+ struct dquot *got[MAXQUOTAS] = {};
struct super_block *sb = inode->i_sb;
qsize_t rsv;
int ret = 0;
@@ -1590,7 +1544,7 @@ static int __dquot_initialize(struct inode *inode, int type)
if (!got[cnt])
continue;
if (!dquots[cnt]) {
- dquots[cnt] = got[cnt];
+ rcu_assign_pointer(dquots[cnt], got[cnt]);
got[cnt] = NULL;
/*
* Make quota reservation system happy if someone
@@ -1598,12 +1552,16 @@ static int __dquot_initialize(struct inode *inode, int type)
*/
rsv = inode_get_rsv_space(inode);
if (unlikely(rsv)) {
+ struct dquot *dquot = srcu_dereference_check(
+ dquots[cnt], &dquot_srcu,
+ lockdep_is_held(&dq_data_lock));
+
spin_lock(&inode->i_lock);
/* Get reservation again under proper lock */
rsv = __inode_get_rsv_space(inode);
- spin_lock(&dquots[cnt]->dq_dqb_lock);
- dquots[cnt]->dq_dqb.dqb_rsvspace += rsv;
- spin_unlock(&dquots[cnt]->dq_dqb_lock);
+ spin_lock(&dquot->dq_dqb_lock);
+ dquot->dq_dqb.dqb_rsvspace += rsv;
+ spin_unlock(&dquot->dq_dqb_lock);
spin_unlock(&inode->i_lock);
}
}
@@ -1625,7 +1583,7 @@ EXPORT_SYMBOL(dquot_initialize);
bool dquot_initialize_needed(struct inode *inode)
{
- struct dquot **dquots;
+ struct dquot __rcu **dquots;
int i;
if (!inode_quota_active(inode))
@@ -1650,13 +1608,14 @@ EXPORT_SYMBOL(dquot_initialize_needed);
static void __dquot_drop(struct inode *inode)
{
int cnt;
- struct dquot **dquots = i_dquot(inode);
+ struct dquot __rcu **dquots = i_dquot(inode);
struct dquot *put[MAXQUOTAS];
spin_lock(&dq_data_lock);
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
- put[cnt] = dquots[cnt];
- dquots[cnt] = NULL;
+ put[cnt] = srcu_dereference_check(dquots[cnt], &dquot_srcu,
+ lockdep_is_held(&dq_data_lock));
+ rcu_assign_pointer(dquots[cnt], NULL);
}
spin_unlock(&dq_data_lock);
dqput_all(put);
@@ -1664,7 +1623,7 @@ static void __dquot_drop(struct inode *inode)
void dquot_drop(struct inode *inode)
{
- struct dquot * const *dquots;
+ struct dquot __rcu * const *dquots;
int cnt;
if (IS_NOQUOTA(inode))
@@ -1737,7 +1696,8 @@ int __dquot_alloc_space(struct inode *inode, qsize_t number, int flags)
int cnt, ret = 0, index;
struct dquot_warn warn[MAXQUOTAS];
int reserve = flags & DQUOT_SPACE_RESERVE;
- struct dquot **dquots;
+ struct dquot __rcu **dquots;
+ struct dquot *dquot;
if (!inode_quota_active(inode)) {
if (reserve) {
@@ -1757,27 +1717,26 @@ int __dquot_alloc_space(struct inode *inode, qsize_t number, int flags)
index = srcu_read_lock(&dquot_srcu);
spin_lock(&inode->i_lock);
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
- if (!dquots[cnt])
+ dquot = srcu_dereference(dquots[cnt], &dquot_srcu);
+ if (!dquot)
continue;
if (reserve) {
- ret = dquot_add_space(dquots[cnt], 0, number, flags,
- &warn[cnt]);
+ ret = dquot_add_space(dquot, 0, number, flags, &warn[cnt]);
} else {
- ret = dquot_add_space(dquots[cnt], number, 0, flags,
- &warn[cnt]);
+ ret = dquot_add_space(dquot, number, 0, flags, &warn[cnt]);
}
if (ret) {
/* Back out changes we already did */
for (cnt--; cnt >= 0; cnt--) {
- if (!dquots[cnt])
+ dquot = srcu_dereference(dquots[cnt], &dquot_srcu);
+ if (!dquot)
continue;
- spin_lock(&dquots[cnt]->dq_dqb_lock);
+ spin_lock(&dquot->dq_dqb_lock);
if (reserve)
- dquot_free_reserved_space(dquots[cnt],
- number);
+ dquot_free_reserved_space(dquot, number);
else
- dquot_decr_space(dquots[cnt], number);
- spin_unlock(&dquots[cnt]->dq_dqb_lock);
+ dquot_decr_space(dquot, number);
+ spin_unlock(&dquot->dq_dqb_lock);
}
spin_unlock(&inode->i_lock);
goto out_flush_warn;
@@ -1807,7 +1766,8 @@ int dquot_alloc_inode(struct inode *inode)
{
int cnt, ret = 0, index;
struct dquot_warn warn[MAXQUOTAS];
- struct dquot * const *dquots;
+ struct dquot __rcu * const *dquots;
+ struct dquot *dquot;
if (!inode_quota_active(inode))
return 0;
@@ -1818,17 +1778,19 @@ int dquot_alloc_inode(struct inode *inode)
index = srcu_read_lock(&dquot_srcu);
spin_lock(&inode->i_lock);
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
- if (!dquots[cnt])
+ dquot = srcu_dereference(dquots[cnt], &dquot_srcu);
+ if (!dquot)
continue;
- ret = dquot_add_inodes(dquots[cnt], 1, &warn[cnt]);
+ ret = dquot_add_inodes(dquot, 1, &warn[cnt]);
if (ret) {
for (cnt--; cnt >= 0; cnt--) {
- if (!dquots[cnt])
+ dquot = srcu_dereference(dquots[cnt], &dquot_srcu);
+ if (!dquot)
continue;
/* Back out changes we already did */
- spin_lock(&dquots[cnt]->dq_dqb_lock);
- dquot_decr_inodes(dquots[cnt], 1);
- spin_unlock(&dquots[cnt]->dq_dqb_lock);
+ spin_lock(&dquot->dq_dqb_lock);
+ dquot_decr_inodes(dquot, 1);
+ spin_unlock(&dquot->dq_dqb_lock);
}
goto warn_put_all;
}
@@ -1849,7 +1811,8 @@ EXPORT_SYMBOL(dquot_alloc_inode);
*/
int dquot_claim_space_nodirty(struct inode *inode, qsize_t number)
{
- struct dquot **dquots;
+ struct dquot __rcu **dquots;
+ struct dquot *dquot;
int cnt, index;
if (!inode_quota_active(inode)) {
@@ -1865,9 +1828,8 @@ int dquot_claim_space_nodirty(struct inode *inode, qsize_t number)
spin_lock(&inode->i_lock);
/* Claim reserved quotas to allocated quotas */
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
- if (dquots[cnt]) {
- struct dquot *dquot = dquots[cnt];
-
+ dquot = srcu_dereference(dquots[cnt], &dquot_srcu);
+ if (dquot) {
spin_lock(&dquot->dq_dqb_lock);
if (WARN_ON_ONCE(dquot->dq_dqb.dqb_rsvspace < number))
number = dquot->dq_dqb.dqb_rsvspace;
@@ -1891,7 +1853,8 @@ EXPORT_SYMBOL(dquot_claim_space_nodirty);
*/
void dquot_reclaim_space_nodirty(struct inode *inode, qsize_t number)
{
- struct dquot **dquots;
+ struct dquot __rcu **dquots;
+ struct dquot *dquot;
int cnt, index;
if (!inode_quota_active(inode)) {
@@ -1907,9 +1870,8 @@ void dquot_reclaim_space_nodirty(struct inode *inode, qsize_t number)
spin_lock(&inode->i_lock);
/* Claim reserved quotas to allocated quotas */
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
- if (dquots[cnt]) {
- struct dquot *dquot = dquots[cnt];
-
+ dquot = srcu_dereference(dquots[cnt], &dquot_srcu);
+ if (dquot) {
spin_lock(&dquot->dq_dqb_lock);
if (WARN_ON_ONCE(dquot->dq_dqb.dqb_curspace < number))
number = dquot->dq_dqb.dqb_curspace;
@@ -1935,7 +1897,8 @@ void __dquot_free_space(struct inode *inode, qsize_t number, int flags)
{
unsigned int cnt;
struct dquot_warn warn[MAXQUOTAS];
- struct dquot **dquots;
+ struct dquot __rcu **dquots;
+ struct dquot *dquot;
int reserve = flags & DQUOT_SPACE_RESERVE, index;
if (!inode_quota_active(inode)) {
@@ -1956,17 +1919,18 @@ void __dquot_free_space(struct inode *inode, qsize_t number, int flags)
int wtype;
warn[cnt].w_type = QUOTA_NL_NOWARN;
- if (!dquots[cnt])
+ dquot = srcu_dereference(dquots[cnt], &dquot_srcu);
+ if (!dquot)
continue;
- spin_lock(&dquots[cnt]->dq_dqb_lock);
- wtype = info_bdq_free(dquots[cnt], number);
+ spin_lock(&dquot->dq_dqb_lock);
+ wtype = info_bdq_free(dquot, number);
if (wtype != QUOTA_NL_NOWARN)
- prepare_warning(&warn[cnt], dquots[cnt], wtype);
+ prepare_warning(&warn[cnt], dquot, wtype);
if (reserve)
- dquot_free_reserved_space(dquots[cnt], number);
+ dquot_free_reserved_space(dquot, number);
else
- dquot_decr_space(dquots[cnt], number);
- spin_unlock(&dquots[cnt]->dq_dqb_lock);
+ dquot_decr_space(dquot, number);
+ spin_unlock(&dquot->dq_dqb_lock);
}
if (reserve)
*inode_reserved_space(inode) -= number;
@@ -1990,7 +1954,8 @@ void dquot_free_inode(struct inode *inode)
{
unsigned int cnt;
struct dquot_warn warn[MAXQUOTAS];
- struct dquot * const *dquots;
+ struct dquot __rcu * const *dquots;
+ struct dquot *dquot;
int index;
if (!inode_quota_active(inode))
@@ -2001,16 +1966,16 @@ void dquot_free_inode(struct inode *inode)
spin_lock(&inode->i_lock);
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
int wtype;
-
warn[cnt].w_type = QUOTA_NL_NOWARN;
- if (!dquots[cnt])
+ dquot = srcu_dereference(dquots[cnt], &dquot_srcu);
+ if (!dquot)
continue;
- spin_lock(&dquots[cnt]->dq_dqb_lock);
- wtype = info_idq_free(dquots[cnt], 1);
+ spin_lock(&dquot->dq_dqb_lock);
+ wtype = info_idq_free(dquot, 1);
if (wtype != QUOTA_NL_NOWARN)
- prepare_warning(&warn[cnt], dquots[cnt], wtype);
- dquot_decr_inodes(dquots[cnt], 1);
- spin_unlock(&dquots[cnt]->dq_dqb_lock);
+ prepare_warning(&warn[cnt], dquot, wtype);
+ dquot_decr_inodes(dquot, 1);
+ spin_unlock(&dquot->dq_dqb_lock);
}
spin_unlock(&inode->i_lock);
mark_all_dquot_dirty(dquots);
@@ -2036,8 +2001,9 @@ int __dquot_transfer(struct inode *inode, struct dquot **transfer_to)
qsize_t cur_space;
qsize_t rsv_space = 0;
qsize_t inode_usage = 1;
+ struct dquot __rcu **dquots;
struct dquot *transfer_from[MAXQUOTAS] = {};
- int cnt, ret = 0;
+ int cnt, index, ret = 0;
char is_valid[MAXQUOTAS] = {};
struct dquot_warn warn_to[MAXQUOTAS];
struct dquot_warn warn_from_inodes[MAXQUOTAS];
@@ -2068,6 +2034,7 @@ int __dquot_transfer(struct inode *inode, struct dquot **transfer_to)
}
cur_space = __inode_get_bytes(inode);
rsv_space = __inode_get_rsv_space(inode);
+ dquots = i_dquot(inode);
/*
* Build the transfer_from list, check limits, and update usage in
* the target structures.
@@ -2082,7 +2049,8 @@ int __dquot_transfer(struct inode *inode, struct dquot **transfer_to)
if (!sb_has_quota_active(inode->i_sb, cnt))
continue;
is_valid[cnt] = 1;
- transfer_from[cnt] = i_dquot(inode)[cnt];
+ transfer_from[cnt] = srcu_dereference_check(dquots[cnt],
+ &dquot_srcu, lockdep_is_held(&dq_data_lock));
ret = dquot_add_inodes(transfer_to[cnt], inode_usage,
&warn_to[cnt]);
if (ret)
@@ -2121,13 +2089,21 @@ int __dquot_transfer(struct inode *inode, struct dquot **transfer_to)
rsv_space);
spin_unlock(&transfer_from[cnt]->dq_dqb_lock);
}
- i_dquot(inode)[cnt] = transfer_to[cnt];
+ rcu_assign_pointer(dquots[cnt], transfer_to[cnt]);
}
spin_unlock(&inode->i_lock);
spin_unlock(&dq_data_lock);
- mark_all_dquot_dirty(transfer_from);
- mark_all_dquot_dirty(transfer_to);
+ /*
+ * These arrays are local and we hold dquot references so we don't need
+ * the srcu protection but still take dquot_srcu to avoid warning in
+ * mark_all_dquot_dirty().
+ */
+ index = srcu_read_lock(&dquot_srcu);
+ mark_all_dquot_dirty((struct dquot __rcu **)transfer_from);
+ mark_all_dquot_dirty((struct dquot __rcu **)transfer_to);
+ srcu_read_unlock(&dquot_srcu, index);
+
flush_warnings(warn_to);
flush_warnings(warn_from_inodes);
flush_warnings(warn_from_space);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-22 21:27:12 +0000