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Date: Fri, 30 Nov 2018 19:21:02 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-aio@kvack.org, hch@lst.de
Subject: Re: [PATCH 24/27] block: implement bio helper to add iter kvec pages
 to bio
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 <20181130165646.27341-25-axboe@kernel.dk>
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On Fri, Nov 30, 2018 at 09:56:43AM -0700, Jens Axboe wrote:
> For an ITER_KVEC, we can just iterate the iov and add the pages
> to the bio directly.

> +		page = virt_to_page(kv->iov_base);
> +		size = bio_add_page(bio, page, kv->iov_len,
> +					offset_in_page(kv->iov_base));

Who said that you *can* do virt_to_page() on those?  E.g. vmalloc()'ed
addresses are fine for ITER_KVEC, etc.