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Date:   Tue, 30 May 2023 15:47:40 +0530
From:   Nitesh Shetty <nj.shetty@samsung.com>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Jens Axboe <axboe@kernel.dk>, Alasdair Kergon <agk@redhat.com>,
        Mike Snitzer <snitzer@kernel.org>, dm-devel@redhat.com,
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        Sagi Grimberg <sagi@grimberg.me>,
        James Smart <james.smart@broadcom.com>,
        Chaitanya Kulkarni <kch@nvidia.com>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <brauner@kernel.org>,
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Subject: Re: [PATCH v11 2/9] block: Add copy offload support infrastructure
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On 23/05/29 06:55PM, Matthew Wilcox wrote:
>On Mon, May 22, 2023 at 04:11:33PM +0530, Nitesh Shetty wrote:
>> +		token = alloc_page(gfp_mask);
>
>Why is PAGE_SIZE the right size for 'token'?  That seems quite unlikely.
>I could understand it being SECTOR_SIZE or something that's dependent on
>the device, but I cannot fathom it being dependent on the host' page size.

This has nothing to do with block device at this point, merely a place
holder to store information about copy offload such as src sectors, len.
Token will be typecasted by driver to get copy info.
SECTOR_SIZE also should work in this case, will update in next version.

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