On 3/7/18 3:02 AM, Misono, Tomohiro wrote:
> On 2018/03/03 3:47, jeffm@suse.com wrote:
>> From: Jeff Mahoney <jeffm@suse.com>
>>
>> The only mechanism we have in the progs for searching qgroups is to load
>> all of them and filter the results.  This works for qgroup show but
>> to add quota information to 'btrfs subvoluem show' it's pretty wasteful.
>>
>> This patch splits out setting up the search and performing the search so
>> we can search for a single qgroupid more easily.
>>
>> Signed-off-by: Jeff Mahoney <jeffm@suse.com>
>> ---
>>  qgroup.c | 98 +++++++++++++++++++++++++++++++++++++++++++++-------------------
>>  qgroup.h |  7 +++++
>>  2 files changed, 77 insertions(+), 28 deletions(-)
>>
>> diff --git a/qgroup.c b/qgroup.c
>> index b1be3311..2d0a6947 100644
>> --- a/qgroup.c
>> +++ b/qgroup.c
>> @@ -1146,11 +1146,11 @@ static inline void print_status_flag_warning(u64 flags)
>>  		warning("qgroup data inconsistent, rescan recommended");
>>  }
>>  
>> -static int __qgroups_search(int fd, struct qgroup_lookup *qgroup_lookup)
>> +static int __qgroups_search(int fd, struct btrfs_ioctl_search_args *args,
>> +			    struct qgroup_lookup *qgroup_lookup)
>>  {
>>  	int ret;
>> -	struct btrfs_ioctl_search_args args;
>> -	struct btrfs_ioctl_search_key *sk = &args.key;
>> +	struct btrfs_ioctl_search_key *sk = &args->key;
>>  	struct btrfs_ioctl_search_header *sh;
>>  	unsigned long off = 0;
>>  	unsigned int i;
>> @@ -1161,30 +1161,12 @@ static int __qgroups_search(int fd, struct qgroup_lookup *qgroup_lookup)
>>  	u64 qgroupid;
>>  	u64 qgroupid1;
>>  
>> -	memset(&args, 0, sizeof(args));
>> -
>> -	sk->tree_id = BTRFS_QUOTA_TREE_OBJECTID;
>> -	sk->max_type = BTRFS_QGROUP_RELATION_KEY;
>> -	sk->min_type = BTRFS_QGROUP_STATUS_KEY;
>> -	sk->max_objectid = (u64)-1;
>> -	sk->max_offset = (u64)-1;
>> -	sk->max_transid = (u64)-1;
>> -	sk->nr_items = 4096;
>> -
>>  	qgroup_lookup_init(qgroup_lookup);
>>  
>>  	while (1) {
>> -		ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args);
>> +		ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, args);
>>  		if (ret < 0) {
>> -			if (errno == ENOENT) {
>> -				error("can't list qgroups: quotas not enabled");
>> -				ret = -ENOTTY;
>> -			} else {
>> -				error("can't list qgroups: %s",
>> -				       strerror(errno));
>> -				ret = -errno;
>> -			}
>> -
>> +			ret = -errno;
> 
> Originally, -ENOTTY would be returned when qgroup is disabled
> but this changes to return -ENOENT. so, it seems that error check
> in 7th patch would not work correctly when qgroup is disabled.
> 

Good catch.

Thanks,

-Jeff

-- 
Jeff Mahoney
SUSE Labs