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Date:   Tue, 25 Jan 2022 16:40:19 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Ming Lei <ming.lei@redhat.com>
Cc:     Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
        linux-block@vger.kernel.org, Vivek Goyal <vgoyal@redhat.com>,
        Pei Zhang <pezhang@redhat.com>
Subject: Re: [PATCH V2] block: loop:use kstatfs.f_bsize of backing file to
 set discard granularity
Message-ID: <20220125154019.GA4536@lst.de>
References: <20220125044005.211943-1-ming.lei@redhat.com> <20220125061057.GA26444@lst.de> <Ye/CiFZSHmHQ3Pfu@T590>
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On Tue, Jan 25, 2022 at 05:27:36PM +0800, Ming Lei wrote:
> 
> But it is configure code path, even though vfs_statfs() fails,
> loop_config_discard() still need to keep discard setting consistent.
> 
> Setting granularity as PAGE_SIZE is just for making discard granularity
> matched with max_discard_sectors. Or you have better/simpler handling?

I'd fail the entire configuration preferably. Or at least not support
discard at all.