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Message-ID: <7a311f7e-a404-4ebe-f90b-af9068bab2fc@bytedance.com>
Date:   Tue, 31 May 2022 20:18:51 +0100
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Subject: Re: [External] Re: [PATCH 0/5] io_uring: add opcodes for current
 working directory
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To:     Jens Axboe <axboe@kernel.dk>, io-uring@vger.kernel.org,
        linux-kernel@vger.kernel.org
Cc:     fam.zheng@bytedance.com
References: <20220531184125.2665210-1-usama.arif@bytedance.com>
 <da4e94f7-94ce-ad57-ad15-c9117c4fef2d@kernel.dk>
From:   Usama Arif <usama.arif@bytedance.com>
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On 31/05/2022 19:58, Jens Axboe wrote:
> On 5/31/22 12:41 PM, Usama Arif wrote:
>> This provides consistency between io_uring and the respective I/O syscall
>> and avoids having the user of liburing specify the cwd in sqe when working
>> with current working directory, for e.g. the user can directly call with
>> IORING_OP_RENAME instead of IORING_OP_RENAMEAT and providing AT_FDCWD in
>> sqe->fd and sqe->len, similar to syscall interface.
>>
>> This is done for rename, unlink, mkdir, symlink and link in this
>> patch-series.
>>
>> The tests for these opcodes in liburing are present at
>> https://github.com/uarif1/liburing/tree/cwd_opcodes. If the patches are
>> acceptable, I am happy to create a PR in above for the tests.
> 
> Can't we just provide prep helpers for them in liburing?
> 

We could add a io_uring_prep_unlink with IORING_OP_UNLINKAT and AT_FDCWD 
in liburing. But i guess adding in kernel adds a more consistent 
interface? and allows to make calls bypassing liburing (although i guess 
people probably don't bypass liburing that much :))

Making the changes in both kernel and liburing provides more of a 
standard interface in my opinion so maybe it looks better. But happy to 
just create a PR in liburing only with prep helpers as you suggested if 
you think that is better?

Thanks!