ext4: verify block bitmap even after fresh initialization

If we want to rely on the buffer_verified() flag of the block bitmap
buffer, we have to set it consistently. However currently if we're
initializing uninitialized block bitmap in
ext4_read_block_bitmap_nowait() we're not going to set buffer verified
at all.

We can do this by simply setting the flag on the buffer, but I think
it's actually better to run ext4_validate_block_bitmap() to make sure
that what we did in the ext4_init_block_bitmap() is right.

So run ext4_validate_block_bitmap() even after the block bitmap
initialization. Also bail out early from ext4_validate_block_bitmap() if
we see corrupt bitmap, since we already know it's corrupt and we do not
need to verify that.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index 955bf49a79455ef09ac8ff24940ba808d68f6554..cd6ea29be6457b52b442ec0a159e5732fad9563f 100644 (file)
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -369,7 +369,7 @@ static void ext4_validate_block_bitmap(struct super_block *sb,
        struct ext4_group_info *grp = ext4_get_group_info(sb, block_group);
        struct ext4_sb_info *sbi = EXT4_SB(sb);
 
-       if (buffer_verified(bh))
+       if (buffer_verified(bh) || EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
                return;
 
        ext4_lock_group(sb, block_group);
@@ -446,7 +446,7 @@ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group)
                unlock_buffer(bh);
                if (err)
                        ext4_error(sb, "Checksum bad for grp %u", block_group);
-               return bh;
+               goto verify;
        }
        ext4_unlock_group(sb, block_group);
        if (buffer_uptodate(bh)) {