As described in commit 02117b8ae9c0 ("f2fs: Set GF_NOFS in
read_cache_page_gfp while doing f2fs_quota_read"), we must not enter
filesystem reclaim while holding the dq_lock. Prevent this more generally
by using memalloc_nofs_save() while holding the lock.
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
fs/quota/dquot.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index a74aef99bd3d..cdb22d6d7488 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -425,9 +425,11 @@ EXPORT_SYMBOL(mark_info_dirty);
int dquot_acquire(struct dquot *dquot)
{
int ret = 0, ret2 = 0;
+ unsigned int memalloc;
struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
mutex_lock(&dquot->dq_lock);
+ memalloc = memalloc_nofs_save();
if (!test_bit(DQ_READ_B, &dquot->dq_flags)) {
ret = dqopt->ops[dquot->dq_id.type]->read_dqblk(dquot);
if (ret < 0)
@@ -458,6 +460,7 @@ int dquot_acquire(struct dquot *dquot)
smp_mb__before_atomic();
set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
out_iolock:
+ memalloc_nofs_restore(memalloc);
mutex_unlock(&dquot->dq_lock);
return ret;
}
@@ -469,9 +472,11 @@ EXPORT_SYMBOL(dquot_acquire);
int dquot_commit(struct dquot *dquot)
{
int ret = 0;
+ unsigned int memalloc;
struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
mutex_lock(&dquot->dq_lock);
+ memalloc = memalloc_nofs_save();
if (!clear_dquot_dirty(dquot))
goto out_lock;
/* Inactive dquot can be only if there was error during read/init
@@ -481,6 +486,7 @@ int dquot_commit(struct dquot *dquot)
else
ret = -EIO;
out_lock:
+ memalloc_nofs_restore(memalloc);
mutex_unlock(&dquot->dq_lock);
return ret;
}
@@ -492,9 +498,11 @@ EXPORT_SYMBOL(dquot_commit);
int dquot_release(struct dquot *dquot)
{
int ret = 0, ret2 = 0;
+ unsigned int memalloc;
struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
mutex_lock(&dquot->dq_lock);
+ memalloc = memalloc_nofs_save();
/* Check whether we are not racing with some other dqget() */
if (dquot_is_busy(dquot))
goto out_dqlock;
@@ -510,6 +518,7 @@ int dquot_release(struct dquot *dquot)
}
clear_bit(DQ_ACTIVE_B, &dquot->dq_flags);
out_dqlock:
+ memalloc_nofs_restore(memalloc);
mutex_unlock(&dquot->dq_lock);
return ret;
}
--
2.35.1
