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 BA0D7C4743E for ; Sun, 6 Jun 2021 19:12:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 99F8061287 for ; Sun, 6 Jun 2021 19:12:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231326AbhFFTOC (ORCPT ); Sun, 6 Jun 2021 15:14:02 -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 S230177AbhFFTMq (ORCPT ); Sun, 6 Jun 2021 15:12:46 -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 5D893C0617A8; Sun, 6 Jun 2021 12:10:56 -0700 (PDT) Received: from viro by zeniv-ca.linux.org.uk with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1lpyAh-0056c7-7u; Sun, 06 Jun 2021 19:10:55 +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 30/37] pull handling of ->iov_offset into iterate_{iovec,bvec,xarray} Date: Sun, 6 Jun 2021 19:10:44 +0000 Message-Id: <20210606191051.1216821-30-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 fewer arguments (by one, but still...) for iterate_...() macros Signed-off-by: Al Viro --- lib/iov_iter.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 8a7a8e5f4155..c1580e574d76 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -17,8 +17,9 @@ #define PIPE_PARANOIA /* for now */ /* covers iovec and kvec alike */ -#define iterate_iovec(i, n, base, len, off, __p, skip, STEP) { \ +#define iterate_iovec(i, n, base, len, off, __p, STEP) { \ size_t off = 0; \ + size_t skip = i->iov_offset; \ do { \ len = min(n, __p->iov_len - skip); \ if (likely(len)) { \ @@ -33,18 +34,20 @@ __p++; \ skip = 0; \ } while (n); \ + i->iov_offset = skip; \ n = off; \ } -#define iterate_bvec(i, n, base, len, off, p, skip, STEP) { \ +#define iterate_bvec(i, n, base, len, off, p, STEP) { \ size_t off = 0; \ + unsigned skip = i->iov_offset; \ while (n) { \ unsigned offset = p->bv_offset + skip; \ unsigned left; \ void *kaddr = kmap_local_page(p->bv_page + \ offset / PAGE_SIZE); \ base = kaddr + offset % PAGE_SIZE; \ - len = min(min(n, p->bv_len - skip), \ + len = min(min(n, (size_t)(p->bv_len - skip)), \ (size_t)(PAGE_SIZE - offset % PAGE_SIZE)); \ left = (STEP); \ kunmap_local(kaddr); \ @@ -59,15 +62,16 @@ if (left) \ break; \ } \ + i->iov_offset = skip; \ n = off; \ } -#define iterate_xarray(i, n, base, len, __off, skip, STEP) { \ +#define iterate_xarray(i, n, base, len, __off, STEP) { \ __label__ __out; \ size_t __off = 0; \ struct page *head = NULL; \ size_t offset; \ - loff_t start = i->xarray_start + skip; \ + loff_t start = i->xarray_start + i->iov_offset; \ pgoff_t index = start >> PAGE_SHIFT; \ int j; \ \ @@ -100,7 +104,7 @@ } \ __out: \ rcu_read_unlock(); \ - skip += __off; \ + i->iov_offset += __off; \ n = __off; \ } @@ -108,13 +112,12 @@ __out: \ if (unlikely(i->count < n)) \ n = i->count; \ if (likely(n)) { \ - size_t skip = i->iov_offset; \ if (likely(iter_is_iovec(i))) { \ const struct iovec *iov = i->iov; \ void __user *base; \ size_t len; \ iterate_iovec(i, n, base, len, off, \ - iov, skip, (I)) \ + iov, (I)) \ i->nr_segs -= iov - i->iov; \ i->iov = iov; \ } else if (iov_iter_is_bvec(i)) { \ @@ -122,7 +125,7 @@ __out: \ void *base; \ size_t len; \ iterate_bvec(i, n, base, len, off, \ - bvec, skip, (K)) \ + bvec, (K)) \ i->nr_segs -= bvec - i->bvec; \ i->bvec = bvec; \ } else if (iov_iter_is_kvec(i)) { \ @@ -130,17 +133,16 @@ __out: \ void *base; \ size_t len; \ iterate_iovec(i, n, base, len, off, \ - kvec, skip, (K)) \ + kvec, (K)) \ i->nr_segs -= kvec - i->kvec; \ i->kvec = kvec; \ } else if (iov_iter_is_xarray(i)) { \ void *base; \ size_t len; \ iterate_xarray(i, n, base, len, off, \ - skip, (K)) \ + (K)) \ } \ i->count -= n; \ - i->iov_offset = skip; \ } \ } #define iterate_and_advance(i, n, base, len, off, I, K) \ -- 2.11.0