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 <hirofumi@mail.parknet.co.jp>
Reported-by: Laurent GUERBY <laurent@guerby.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 6b74d09..de0004f 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -202,9 +202,9 @@
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;
}