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Date:   Mon, 28 Aug 2023 15:09:34 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Christian Brauner <brauner@kernel.org>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Kemeng Shi <shikemeng@huaweicloud.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] vfs: use helpers for calling f_op->{read,write}_iter()
 in read_write.c
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On Mon, Aug 28, 2023 at 02:30:42PM +0200, Christian Brauner wrote:
> On Mon, Aug 28, 2023 at 05:00:36AM -0700, Christoph Hellwig wrote:
> > On Mon, Aug 28, 2023 at 11:50:56PM +0800, Kemeng Shi wrote:
> > > use helpers for calling f_op->{read,write}_iter() in read_write.c
> > > 
> > 
> > Why?  We really should just remove the completely pointless wrappers
> > instead.
> 
> Especially because it means you chase this helper to figure out what's
> actually going on. If there was more to it then it would make sense but
> not just as a pointless wrapper.

It's borderline easier to grep for, but not dramatically so.  call_mmap()
has a stronger argument in favour - there are several methods called
->mmap and telling one from another is hard without looking into context.

For ->{read,write}_iter() I'd prefer to get rid of the wrappers.