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Date: Fri, 1 Jun 2018 01:43:02 -0700
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [RESEND PATCH V5 00/33] block: support multipage bvec
Message-ID: <20180601084302.GB30694@infradead.org>
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To: Ming Lei <ming.lei@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>, Kent Overstreet <kent.overstreet@gmail.com>, Christoph Hellwig <hch@infradead.org>, Alexander Viro <viro@zeniv.linux.org.uk>, David Sterba <dsterba@suse.cz>, Huang Ying <ying.huang@intel.com>, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Theodore Ts'o <tytso@mit.edu>, "Darrick J . Wong" <darrick.wong@oracle.com>, Coly Li <colyli@suse.de>, Filipe Manana <fdmanana@gmail.com>

On Mon, May 28, 2018 at 10:30:43AM +0800, Ming Lei wrote:
> I hate the conversion too, but looks it can't be avoided since
> bio_for_each_segment_all() has to be changed.

I guess you mean what is currently bio_for_each_page_all in your
tree which now takes a bvec_iter_all agument?  We could just
try to hide the bia variable initially under an unlike to be used
name, and then slowly move to the proper bio_for_each_page_all
API unhiding it with the rename.

But I think your current bio_for_each_segment_all should just
go away.  All three users really should be using better abstractions.