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Message-ID: <0d62615c-57d1-922b-5ebc-32faabf33327@deltatee.com>
Date:   Tue, 6 Dec 2022 09:43:39 -0700
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To:     David Howells <dhowells@redhat.com>,
        Al Viro <viro@zeniv.linux.org.uk>
Cc:     Christoph Hellwig <hch@lst.de>, John Hubbard <jhubbard@nvidia.com>,
        Matthew Wilcox <willy@infradead.org>,
        linux-fsdevel@vger.kernel.org, linux-mm@kvack.org,
        Christoph Hellwig <hch@infradead.org>,
        Jeff Layton <jlayton@kernel.org>, linux-kernel@vger.kernel.org
References: <166997419665.9475.15014699817597102032.stgit@warthog.procyon.org.uk>
 <166997421646.9475.14837976344157464997.stgit@warthog.procyon.org.uk>
From:   Logan Gunthorpe <logang@deltatee.com>
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Subject: Re: [PATCH v3 2/4] iov_iter: Add a function to extract a page list
 from an iterator
Precedence: bulk


On 2022-12-02 02:43, David Howells wrote:
> Add a function, iov_iter_extract_pages(), to extract a list of pages from
> an iterator.  The pages may be returned with a reference added or a pin
> added or neither, depending on the type of iterator and the direction of
> transfer.
> +static ssize_t iov_iter_extract_user_pages(struct iov_iter *i,
> +					   struct page ***pages, size_t maxsize,
> +					   unsigned int maxpages,
> +					   size_t *offset0,
> +					   unsigned int *cleanup_mode)

If this is going to be a general replacement for iov_iter_get_pages()
it's going to need to pass through gup_flags. My recent patchset added
versions with these and I think it should be in during the next merge
cycle. [1]

Thanks,

Logan


[1] https://lore.kernel.org/all/20221021174116.7200-4-logang@deltatee.com/