From patchwork Sat May 7 21:52:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 570710 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 44823C433FE for ; Sat, 7 May 2022 21:52:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233529AbiEGV4W (ORCPT ); Sat, 7 May 2022 17:56:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55358 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1387528AbiEGV4U (ORCPT ); Sat, 7 May 2022 17:56:20 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0D30EFD10; Sat, 7 May 2022 14:52:33 -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 A3C4860F2D; Sat, 7 May 2022 21:52:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 065C6C385A6; Sat, 7 May 2022 21:52:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1651960352; bh=1I4TKssy6yHtJB0DOLvoU/YN0ZUywf5dO/iYT5pJTTo=; h=Date:To:From:Subject:From; b=Gh1jcRFxVeCZSBIEIWnFuhczU68nJUtL4y0VZAwJKnYJIPz4vHmeVZKuu5PvrSvpq rzWsPa/OevXv1//F7wddJcKxrT6RwfGgsQ2SiJ0SNH2Rixhq2fjyD981BW20KR+A6m A1naD9dCxPQFtE3gZ+X4D3dhgYEeUXcIcP1zvBis= Date: Sat, 07 May 2022 14:52:31 -0700 To: mm-commits@vger.kernel.org, viro@zeniv.linux.org.uk, stable@vger.kernel.org, avagin@gmail.com, akpm@linux-foundation.org From: Andrew Morton Subject: + fs-sendfile-handles-o_nonblock-of-out_fd.patch added to mm-nonmm-unstable branch Message-Id: <20220507215232.065C6C385A6@smtp.kernel.org> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch titled Subject: fs: sendfile handles O_NONBLOCK of out_fd has been added to the -mm mm-nonmm-unstable branch. Its filename is fs-sendfile-handles-o_nonblock-of-out_fd.patch This patch should soon appear in the mm-nonmm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Andrei Vagin Subject: fs: sendfile handles O_NONBLOCK of out_fd sendfile has to return EAGAIN if out_fd is nonblocking and the write into it would block. Here is a small reproducer for the problem: #define _GNU_SOURCE /* See feature_test_macros(7) */ #include #include #include #include #include #include #include #define FILE_SIZE (1UL << 30) int main(int argc, char **argv) { int p[2], fd; if (pipe2(p, O_NONBLOCK)) return 1; fd = open(argv[1], O_RDWR | O_TMPFILE, 0666); if (fd < 0) return 1; ftruncate(fd, FILE_SIZE); if (sendfile(p[1], fd, 0, FILE_SIZE) == -1) { fprintf(stderr, "FAIL\n"); } if (sendfile(p[1], fd, 0, FILE_SIZE) != -1 || errno != EAGAIN) { fprintf(stderr, "FAIL\n"); } return 0; } It worked before b964bf53e540, it is stuck after b964bf53e540, and it works again with this fix. Link: https://lkml.kernel.org/r/20220415005015.525191-1-avagin@gmail.com Fixes: b964bf53e540 ("teach sendfile(2) to handle send-to-pipe directly") Signed-off-by: Andrei Vagin Cc: Al Viro Cc: Signed-off-by: Andrew Morton --- fs/read_write.c | 3 +++ 1 file changed, 3 insertions(+) --- a/fs/read_write.c~fs-sendfile-handles-o_nonblock-of-out_fd +++ a/fs/read_write.c @@ -1247,6 +1247,9 @@ static ssize_t do_sendfile(int out_fd, i count, fl); file_end_write(out.file); } else { + if (out.file->f_flags & O_NONBLOCK) + fl |= SPLICE_F_NONBLOCK; + retval = splice_file_to_pipe(in.file, opipe, &pos, count, fl); }