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 X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E53AAC4743D for ; Sun, 6 Jun 2021 19:13:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CECE361287 for ; Sun, 6 Jun 2021 19:13:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231338AbhFFTPK (ORCPT ); Sun, 6 Jun 2021 15:15:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54112 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230250AbhFFTMw (ORCPT ); Sun, 6 Jun 2021 15:12:52 -0400 Received: from zeniv-ca.linux.org.uk (zeniv-ca.linux.org.uk [IPv6:2607:5300:60:148a::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7FE63C061795; Sun, 6 Jun 2021 12:11:02 -0700 (PDT) Received: from viro by zeniv-ca.linux.org.uk with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1lpyAg-0056bW-JC; Sun, 06 Jun 2021 19:10:54 +0000 From: Al Viro To: Linus Torvalds Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, David Sterba , Miklos Szeredi , Anton Altaparmakov , David Howells , Matthew Wilcox , Pavel Begunkov Subject: [RFC PATCH 25/37] iterate_bvec(): expand bvec.h macro forest, massage a bit Date: Sun, 6 Jun 2021 19:10:39 +0000 Message-Id: <20210606191051.1216821-25-viro@zeniv.linux.org.uk> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210606191051.1216821-1-viro@zeniv.linux.org.uk> References: <20210606191051.1216821-1-viro@zeniv.linux.org.uk> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: Al Viro Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ... incidentally, using pointer instead of index in an array (the only change here) trims half-kilobyte of .text... Signed-off-by: Al Viro --- lib/iov_iter.c | 33 ++++++++++++++++++++------------- 1 file changed, 20 insertions(+), 13 deletions(-) diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 19c103e9ef7d..af9525c21c77 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -37,14 +37,23 @@ n = wanted - n; \ } -#define iterate_bvec(i, n, __v, __bi, skip, STEP) { \ - struct bvec_iter __start; \ - __start.bi_size = n; \ - __start.bi_bvec_done = skip; \ - __start.bi_idx = 0; \ - for_each_bvec(__v, i->bvec, __bi, __start) { \ - (void)(STEP); \ - } \ +#define iterate_bvec(i, n, __v, p, skip, STEP) { \ + size_t wanted = n; \ + while (n) { \ + unsigned offset = p->bv_offset + skip; \ + __v.bv_offset = offset % PAGE_SIZE; \ + __v.bv_page = p->bv_page + offset / PAGE_SIZE; \ + __v.bv_len = min(min(n, p->bv_len - skip), \ + (size_t)(PAGE_SIZE - offset % PAGE_SIZE)); \ + (void)(STEP); \ + skip += __v.bv_len; \ + if (skip == p->bv_len) { \ + skip = 0; \ + p++; \ + } \ + n -= __v.bv_len; \ + } \ + n = wanted - n; \ } #define iterate_xarray(i, n, __v, skip, STEP) { \ @@ -98,11 +107,9 @@ } else if (iov_iter_is_bvec(i)) { \ const struct bio_vec *bvec = i->bvec; \ struct bio_vec v; \ - struct bvec_iter __bi; \ - iterate_bvec(i, n, v, __bi, skip, (B)) \ - i->bvec = __bvec_iter_bvec(i->bvec, __bi); \ - i->nr_segs -= i->bvec - bvec; \ - skip = __bi.bi_bvec_done; \ + iterate_bvec(i, n, v, bvec, skip, (B)) \ + i->nr_segs -= bvec - i->bvec; \ + i->bvec = bvec; \ } else if (iov_iter_is_kvec(i)) { \ const struct kvec *kvec = i->kvec; \ struct kvec v; \ -- 2.11.0