[LogFS] Prevent mempool_destroy NULL pointer dereference

It would probably be better to just accept NULL pointers in
mempool_destroy().  But for the current -rc series let's keep things
simple.

This patch was lost in the cracks for a while.
Kevin Cernekee <cernekee@gmail.com> had to rediscover the problem and
send a similar patch because of it. :(

Signed-off-by: Joern Engel <joern@logfs.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/fs/logfs/logfs.h b/fs/logfs/logfs.h
index c9929eed80b1..0a3df1a0c936 100644
--- a/fs/logfs/logfs.h
+++ b/fs/logfs/logfs.h
@@ -727,4 +727,10 @@ static inline struct logfs_area *get_area(struct super_block *sb,
         return logfs_super(sb)->s_area[(__force u8)gc_level];
 }
 
+static inline void logfs_mempool_destroy(mempool_t *pool)
+{
+        if (pool)
+                mempool_destroy(pool);
+}
+
 #endif