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Date:   Wed, 31 May 2023 14:37:13 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc:     Christoph Hellwig <hch@lst.de>, Chris Mason <clm@fb.com>,
        Josef Bacik <josef@toxicpanda.com>,
        David Sterba <dsterba@suse.com>, linux-btrfs@vger.kernel.org
Subject: Re: [PATCH 6/6] btrfs: remove need_full_stripe
Message-ID: <20230531123713.GA26932@lst.de>
References: <20230531041740.375963-1-hch@lst.de> <20230531041740.375963-7-hch@lst.de> <f1930f26-6422-8f57-0d4a-7cc431dd1a7c@gmx.com>
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On Wed, May 31, 2023 at 04:52:53PM +0800, Qu Wenruo wrote:
>> need_full_stripe is just a somewhat complicated way to say
>> "op != BTRFS_MAP_READ".  Just spell that explicit check out, which makes
>> a lot of the code currently using the helper easier to understand.
>
> In fact the old "need_full_stripe" can even be confusing, as
> BTRFS_MAP_READ with mirror_num > 1 on RAID56 would still need all the
> stripes.

Yes, that's one of the reasons.  And that in general in the conditionals
READ/!READ tends to explain the logic better than !need_full_stripe vs
need_full_stripe.