Re: btrfs: qgroup: account shared subtrees during snapshot delete

[Mark Fasheh <mfasheh@suse.de>]

Thanks for the review Josef, I will implement everything you mentioned. I
have one question below though:

On Thu, Jun 19, 2014 at 03:25:12PM -0700, Josef Bacik wrote:
> On 06/19/2014 02:49 PM, Mark Fasheh wrote:
>> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
>> index 46f39bf..672d2a4 100644
>> --- a/fs/btrfs/extent-tree.c
>> +++ b/fs/btrfs/extent-tree.c
>> @@ -7472,6 +7703,9 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans,
>>
>>   	if (wc->stage == DROP_REFERENCE) {
>>   		if (wc->refs[level - 1] > 1) {
>> +			account_shared_subtree(trans, root, next, generation,
>> +					       level - 1);
>> +
>
> We don't pay attention to the return value, we should probably abort the
> transaction if there is a problem.

Abort or log an error and continue? I ask because technically we could
continue with the subvolume drop but obviously qgroup state will need to be
fixed via a future rescan. I guess the question is which is more 'friendly'
to the user.
	--Mark

--
Mark Fasheh