Fix _fat_bmap() locking

On swapon() path, it has already i_mutex. So, this uses i_alloc_sem instead of it. Signed-off-by: OGAWA Hirofumi <[email protected]> Reported-by: Laurent GUERBY <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
franciscofranco · Mar 11, 2009 · 3a95ea1 · 3a95ea1
1 parent ad3bdef
commit 3a95ea1
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
@@ -202,9 +202,9 @@ static sector_t _fat_bmap(struct address_space *mapping, sector_t block)
 	sector_t blocknr;
 
 	/* fat_get_cluster() assumes the requested blocknr isn't truncated. */
-	mutex_lock(&mapping->host->i_mutex);
+	down_read(&mapping->host->i_alloc_sem);
 	blocknr = generic_block_bmap(mapping, block, fat_get_block);
-	mutex_unlock(&mapping->host->i_mutex);
+	up_read(&mapping->host->i_alloc_sem);
 
 	return blocknr;
 }