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 018E0C43334 for ; Tue, 28 Jun 2022 11:56:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243647AbiF1L4P (ORCPT ); Tue, 28 Jun 2022 07:56:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53732 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344908AbiF1L4N (ORCPT ); Tue, 28 Jun 2022 07:56:13 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5145931353 for ; Tue, 28 Jun 2022 04:56:11 -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 ams.source.kernel.org (Postfix) with ESMTPS id 0B29BB808C0 for ; Tue, 28 Jun 2022 11:56:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E468BC341CA; Tue, 28 Jun 2022 11:56:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1656417368; bh=scYoXGTf57l+96rQ4SMOfNpE5i8JzGBwIYpwE5KG4Yg=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=laeThc3aXIXjSXsKEp+AqQ6weBcEPn1MlxfEwhcu7KGc47S5h73Kl/bVNxkV4L6nK YmqVRdbDeNaYNr0vIi6GzYvM7wgtrWOZNrqFzwT7qNz3o6l9C8HaNZx8AS8/06KS2j do67NjC6YmiUQ5VonNeeCP2wBs9rY+ZSOsIzge8vyttHmWVsNFomHvcN5HAqIy23QZ k72YBn6IvJLn9IziEQ4cDfgYBFkZPP86buNJbn01uB61ckU5qMi4bgpyd/wU/AOr2u XP53l67csm7tTpM2LhEQavoVm7qFQEWB7YFPoQy09BiB6Cy9uKSBDcBybYy1ZAaoXl GSzUpzX0fL/hQ== Message-ID: <70b0b524f692c5bf42b1ec05df59e99b42dd5562.camel@kernel.org> Subject: Re: [PATCH 30/44] iov_iter: lift dealing with maxpages out of first_{iovec,bvec}_segment() 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 07:56:06 -0400 In-Reply-To: <20220622041552.737754-30-viro@zeniv.linux.org.uk> References: <20220622041552.737754-1-viro@zeniv.linux.org.uk> <20220622041552.737754-30-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: > Signed-off-by: Al Viro > --- > lib/iov_iter.c | 23 +++++++++++------------ > 1 file changed, 11 insertions(+), 12 deletions(-) >=20 > diff --git a/lib/iov_iter.c b/lib/iov_iter.c > index 92a566f839f9..9ef671b101dc 100644 > --- a/lib/iov_iter.c > +++ b/lib/iov_iter.c > @@ -1308,12 +1308,9 @@ static ssize_t iter_xarray_get_pages(struct iov_it= er *i, > =20 > static unsigned long found_ubuf_segment(unsigned long addr, > size_t len, > - size_t *size, size_t *start, > - unsigned maxpages) > + size_t *size, size_t *start) > { > len +=3D (*start =3D addr % PAGE_SIZE); > - if (len > maxpages * PAGE_SIZE) > - len =3D maxpages * PAGE_SIZE; > *size =3D len; > return addr & PAGE_MASK; > } > @@ -1321,14 +1318,14 @@ static unsigned long found_ubuf_segment(unsigned = long addr, > /* must be done on non-empty ITER_UBUF or ITER_IOVEC one */ > static unsigned long first_iovec_segment(const struct iov_iter *i, > size_t *size, size_t *start, > - size_t maxsize, unsigned maxpages) > + size_t maxsize) > { > size_t skip; > long k; > =20 > if (iter_is_ubuf(i)) { > unsigned long addr =3D (unsigned long)i->ubuf + i->iov_offset; > - return found_ubuf_segment(addr, maxsize, size, start, maxpages); > + return found_ubuf_segment(addr, maxsize, size, start); > } > =20 > for (k =3D 0, skip =3D i->iov_offset; k < i->nr_segs; k++, skip =3D 0) = { > @@ -1339,7 +1336,7 @@ static unsigned long first_iovec_segment(const stru= ct iov_iter *i, > continue; > if (len > maxsize) > len =3D maxsize; > - return found_ubuf_segment(addr, len, size, start, maxpages); > + return found_ubuf_segment(addr, len, size, start); > } > BUG(); // if it had been empty, we wouldn't get called > } > @@ -1347,7 +1344,7 @@ static unsigned long first_iovec_segment(const stru= ct iov_iter *i, > /* must be done on non-empty ITER_BVEC one */ > static struct page *first_bvec_segment(const struct iov_iter *i, > size_t *size, size_t *start, > - size_t maxsize, unsigned maxpages) > + size_t maxsize) > { > struct page *page; > size_t skip =3D i->iov_offset, len; > @@ -1358,8 +1355,6 @@ static struct page *first_bvec_segment(const struct= iov_iter *i, > skip +=3D i->bvec->bv_offset; > page =3D i->bvec->bv_page + skip / PAGE_SIZE; > len +=3D (*start =3D skip % PAGE_SIZE); > - if (len > maxpages * PAGE_SIZE) > - len =3D maxpages * PAGE_SIZE; > *size =3D len; > return page; > } > @@ -1387,7 +1382,9 @@ static ssize_t __iov_iter_get_pages_alloc(struct io= v_iter *i, > if (i->nofault) > gup_flags |=3D FOLL_NOFAULT; > =20 > - addr =3D first_iovec_segment(i, &len, start, maxsize, maxpages); > + addr =3D first_iovec_segment(i, &len, start, maxsize); > + if (len > maxpages * PAGE_SIZE) > + len =3D maxpages * PAGE_SIZE; > n =3D DIV_ROUND_UP(len, PAGE_SIZE); > if (!*pages) { > *pages =3D get_pages_array(n); > @@ -1403,7 +1400,9 @@ static ssize_t __iov_iter_get_pages_alloc(struct io= v_iter *i, > struct page **p; > struct page *page; > =20 > - page =3D first_bvec_segment(i, &len, start, maxsize, maxpages); > + page =3D first_bvec_segment(i, &len, start, maxsize); > + if (len > maxpages * PAGE_SIZE) > + len =3D maxpages * PAGE_SIZE; > n =3D DIV_ROUND_UP(len, PAGE_SIZE); > p =3D *pages; > if (!p) { Reviewed-by: Jeff Layton