Re: [PATCH v3 2/2] fiemap: Implement ranged query

Eric Sandeen
2017-11-14T20:54:56Z

On 11/14/17 2:52 PM, Dave Chinner wrote:
> On Tue, Nov 14, 2017 at 07:31:34AM -0600, Eric Sandeen wrote:
>>
>>
>> On 11/14/17 12:32 AM, Nikolay Borisov wrote:
>>>
>>>
>>> On 14.11.2017 00:22, Eric Sandeen wrote:
>>>> On 11/13/17 4:05 PM, Nikolay Borisov wrote:
>>
>> ...
>>
>>>>> You are right this is a bit ugly, but it seems more consistend to me,
>>>>> rather than something like
>>>>>
>>>>> xfs_io -c "fiemap -r -n 10 -v 4k 10k" for example. And the reason why
>>>>> I'm using this hackish way and not declaring r as r: in getopt is
>>>>> because getopt doesn't recognise when a parameter takes more than 1
>>>>> argument.
>>>>
>>>> Sorry for chiming in so late after all the go-rounds, but:
>>>>
>>>> Why not just drop -r entirely, and make fiemap go into ranged mode iff a
>>>> range is specified at the end of the command, i.e.:
>>>>
>>>> fiemap [ -alv ] [ -n nx ] [ offset length ]
>>>
>>> V2 was like that but it required some changing to the generic code which
>>> detects the presence of this feature and Dave objected hence v3.
>>
>> Ok, sorry for being so behind and rehashing old discussions. Let me look
>> at that.
>
> I suggested "-r" because of the fact that you can't detect optional
> parameters in fstests without jumping through really nasty hoops
> involving regex line noise.

Yeah, but I'd rather have nasty stuff in xfstests than in xfsprogs interfaces.

See also my suggestion to try mapping past EOF as a detection method.

-Eric

> Cheers,
>
> Daves.
>