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Date:   Fri, 23 Sep 2022 01:45:44 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Sarthak Kukreti <sarthakkukreti@chromium.org>
Cc:     Christoph Hellwig <hch@infradead.org>, dm-devel@redhat.com,
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Subject: Re: [PATCH RFC 4/8] fs: Introduce FALLOC_FL_PROVISION
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On Tue, Sep 20, 2022 at 10:54:32PM -0700, Sarthak Kukreti wrote:
> [ mmc0blkp1 | ext4(1) | sparse file | loop | dm-thinp | dm-thin | ext4(2) ]
> 
> would be predicated on the guarantees of fallocate() per allocation
> layer; if ext4(1) was replaced by a filesystem that did not support
> fallocate(), then there would be no guarantee that a write to a file
> on ext4(2) succeeds.

a write or any unlimited number of writes?