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Date:   Sat, 25 Mar 2023 01:31:46 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc:     Christoph Hellwig <hch@infradead.org>, Qu Wenruo <wqu@suse.com>,
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Subject: Re: [PATCH v3 02/12] btrfs: introduce a new helper to submit bio for
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On Sat, Mar 25, 2023 at 04:21:41PM +0800, Qu Wenruo wrote:
> No big deal, I can go with the extra fs_info parameter for btrfs_bio_init()
> and btrfs_bio_alloc().

I'd be tempted to just initialize it in the callers given that it's
an optional field now.  I wonder if the same might also make sense
for ->file_offset.

> The main reason I go with the duplicated allocate is to remove the need for
> nr_vecs, but that's pretty minor, thus not a critical one.

Passing nr_vecs might actually make sense.  There is no need to always
allocated all of them for existing callers either, so we can do
additional optimizations based on that later.