quota: missing lock in dqcache_shrink_scan()

Commit 1ab6c49 (fs: convert fs shrinkers to new scan/count API) accidentally removed locking from quota shrinker. Fix it - dqcache_shrink_scan() should use dq_list_lock to protect the scan on free_dquots list. CC: [email protected] Fixes: 1ab6c49 Signed-off-by: Niu Yawei <[email protected]> Signed-off-by: Jan Kara <[email protected]>
kyagi · Jul 15, 2014 · d68aab6 · d68aab6
1 parent 1795cd9
commit d68aab6
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
@@ -702,6 +702,7 @@ dqcache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
 	struct dquot *dquot;
 	unsigned long freed = 0;
 
+	spin_lock(&dq_list_lock);
 	head = free_dquots.prev;
 	while (head != &free_dquots && sc->nr_to_scan) {
 		dquot = list_entry(head, struct dquot, dq_free);
@@ -713,6 +714,7 @@ dqcache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
 		freed++;
 		head = free_dquots.prev;
 	}
+	spin_unlock(&dq_list_lock);
 	return freed;
 }