btrfs: Add checker for EXTENT_CSUM

EXTENT_CSUM checker is a relatively easy one, only needs to check:

1) Objectid
   Fixed to BTRFS_EXTENT_CSUM_OBJECTID

2) Key offset alignment
   Must be aligned to sectorsize

3) Item size alignedment
   Must be aligned to csum size

Signed-off-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Qu Wenruo 2017-08-23 16:57:59 +09:00 committed by David Sterba
parent 40c3c40947
commit 4b865cab96

View file

@ -626,6 +626,27 @@ static int check_extent_data_item(struct btrfs_root *root,
return 0;
}
static int check_csum_item(struct btrfs_root *root, struct extent_buffer *leaf,
struct btrfs_key *key, int slot)
{
u32 sectorsize = root->fs_info->sectorsize;
u32 csumsize = btrfs_super_csum_size(root->fs_info->super_copy);
if (key->objectid != BTRFS_EXTENT_CSUM_OBJECTID) {
CORRUPT("invalid objectid for csum item", leaf, root, slot);
return -EUCLEAN;
}
if (!IS_ALIGNED(key->offset, sectorsize)) {
CORRUPT("unaligned key offset for csum item", leaf, root, slot);
return -EUCLEAN;
}
if (!IS_ALIGNED(btrfs_item_size_nr(leaf, slot), csumsize)) {
CORRUPT("unaligned csum item size", leaf, root, slot);
return -EUCLEAN;
}
return 0;
}
/*
* Common point to switch the item-specific validation.
*/
@ -639,6 +660,9 @@ static int check_leaf_item(struct btrfs_root *root,
case BTRFS_EXTENT_DATA_KEY:
ret = check_extent_data_item(root, leaf, key, slot);
break;
case BTRFS_EXTENT_CSUM_KEY:
ret = check_csum_item(root, leaf, key, slot);
break;
}
return ret;
}