quota: provide function to grab quota structure reference

Provide dqgrab() function to get quota structure reference when we are
sure it already has at least one active reference.  Make use of this
function inside quota code.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index cfc8dcc16043..9cd5f63715c0 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -528,7 +528,7 @@ restart:
                 if (atomic_read(&dquot->dq_count)) {
                         DEFINE_WAIT(wait);
 
-                        atomic_inc(&dquot->dq_count);
+                        dqgrab(dquot);
                         prepare_to_wait(&dquot->dq_wait_unused, &wait,
                                         TASK_UNINTERRUPTIBLE);
                         spin_unlock(&dq_list_lock);
@@ -632,7 +632,7 @@ int dquot_writeback_dquots(struct super_block *sb, int type)
                         /* Now we have active dquot from which someone is
                          * holding reference so we can safely just increase
                          * use count */
-                        atomic_inc(&dquot->dq_count);
+                        dqgrab(dquot);
                         spin_unlock(&dq_list_lock);
                         dqstats_inc(DQST_LOOKUPS);
                         err = sb->dq_op->write_dquot(dquot);