From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2F3F2C433EF for ; Tue, 28 Jun 2022 11:50:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243997AbiF1LuG (ORCPT ); Tue, 28 Jun 2022 07:50:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50378 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239438AbiF1LuF (ORCPT ); Tue, 28 Jun 2022 07:50:05 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 15E45F74 for ; Tue, 28 Jun 2022 04:50:04 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id A6B99609D0 for ; Tue, 28 Jun 2022 11:50:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36AFBC341CA; Tue, 28 Jun 2022 11:50:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1656417003; bh=p5kCKkIZYbPDyOInvkTcyT2axlg7jpWwcO1KxJK54M8=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=Fw8IP6HJ/JW2yV4t3//VLKuc0Yg7/p0fVfdEX0HAiakevauPbOHX9hpiAsHzOAI4x A7QCO9oL1MnFOlMdZWIZaZ3fYb0PCUh72iy+tpCiSGVzm2PHnZGeRiyw6z9sxN7kXw 0fk11M87ikg/goLShUUx8tLazgrX4vVUCfhED9APP7PYAjFwXOynOwwNEVsWCUcgnr ZMXY5LIOyYNqkAfOcJ+PeWppj0zrLSKCubYWJ3ZbZcA5qKXD1FeYjINw0xPPfDqO1Y 6OYFcDEWju2gsP5cTENSLkAhKAqd8R9+ojLtudZzKRQABGpuzGHFAxTH4pIJ3CQB+m JWJs0HAQesXSQ== Message-ID: <6a8dace941ca29717b21fba98dfb865f3423af67.camel@kernel.org> Subject: Re: [PATCH 27/44] unify xarray_get_pages() and xarray_get_pages_alloc() From: Jeff Layton To: Al Viro , linux-fsdevel@vger.kernel.org Cc: Linus Torvalds , Jens Axboe , Christoph Hellwig , Matthew Wilcox , David Howells , Dominique Martinet , Christian Brauner Date: Tue, 28 Jun 2022 07:50:01 -0400 In-Reply-To: <20220622041552.737754-27-viro@zeniv.linux.org.uk> References: <20220622041552.737754-1-viro@zeniv.linux.org.uk> <20220622041552.737754-27-viro@zeniv.linux.org.uk> Content-Type: text/plain; charset="ISO-8859-15" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.44.2 (3.44.2-1.fc36) MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Wed, 2022-06-22 at 05:15 +0100, Al Viro wrote: > same as for pipes >=20 > Signed-off-by: Al Viro > --- > lib/iov_iter.c | 49 ++++++++++--------------------------------------- > 1 file changed, 10 insertions(+), 39 deletions(-) >=20 > diff --git a/lib/iov_iter.c b/lib/iov_iter.c > index 1c98f2f3a581..07dacb274ba5 100644 > --- a/lib/iov_iter.c > +++ b/lib/iov_iter.c > @@ -1276,7 +1276,7 @@ static ssize_t iter_xarray_populate_pages(struct pa= ge **pages, struct xarray *xa > } > =20 > static ssize_t iter_xarray_get_pages(struct iov_iter *i, > - struct page **pages, size_t maxsize, > + struct page ***pages, size_t maxsize, > unsigned maxpages, size_t *_start_offset) > { > unsigned nr, offset; > @@ -1301,7 +1301,13 @@ static ssize_t iter_xarray_get_pages(struct iov_it= er *i, > if (count > maxpages) > count =3D maxpages; > =20 > - nr =3D iter_xarray_populate_pages(pages, i->xarray, index, count); > + if (!*pages) { > + *pages =3D get_pages_array(count); > + if (!*pages) > + return -ENOMEM; > + } > + > + nr =3D iter_xarray_populate_pages(*pages, i->xarray, index, count); > if (nr =3D=3D 0) > return 0; > =20 > @@ -1409,46 +1415,11 @@ ssize_t iov_iter_get_pages(struct iov_iter *i, > if (iov_iter_is_pipe(i)) > return pipe_get_pages(i, &pages, maxsize, maxpages, start); > if (iov_iter_is_xarray(i)) > - return iter_xarray_get_pages(i, pages, maxsize, maxpages, start); > + return iter_xarray_get_pages(i, &pages, maxsize, maxpages, start); > return -EFAULT; > } > EXPORT_SYMBOL(iov_iter_get_pages); > =20 > -static ssize_t iter_xarray_get_pages_alloc(struct iov_iter *i, > - struct page ***pages, size_t maxsize, > - size_t *_start_offset) > -{ > - struct page **p; > - unsigned nr, offset; > - pgoff_t index, count; > - size_t size =3D maxsize; > - loff_t pos; > - > - pos =3D i->xarray_start + i->iov_offset; > - index =3D pos >> PAGE_SHIFT; > - offset =3D pos & ~PAGE_MASK; > - *_start_offset =3D offset; > - > - count =3D 1; > - if (size > PAGE_SIZE - offset) { > - size -=3D PAGE_SIZE - offset; > - count +=3D size >> PAGE_SHIFT; > - size &=3D ~PAGE_MASK; > - if (size) > - count++; > - } > - > - *pages =3D p =3D get_pages_array(count); > - if (!p) > - return -ENOMEM; > - > - nr =3D iter_xarray_populate_pages(p, i->xarray, index, count); > - if (nr =3D=3D 0) > - return 0; > - > - return min_t(size_t, nr * PAGE_SIZE - offset, maxsize); > -} > - > static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i, > struct page ***pages, size_t maxsize, > size_t *start) > @@ -1498,7 +1469,7 @@ static ssize_t __iov_iter_get_pages_alloc(struct io= v_iter *i, > if (iov_iter_is_pipe(i)) > return pipe_get_pages(i, pages, maxsize, ~0U, start); > if (iov_iter_is_xarray(i)) > - return iter_xarray_get_pages_alloc(i, pages, maxsize, start); > + return iter_xarray_get_pages(i, pages, maxsize, ~0U, start); > return -EFAULT; > } > =20 Reviewed-by: Jeff Layton