From patchwork Fri Jun 29 06:03:28 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fam Zheng X-Patchwork-Id: 936621 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 41H5lC6hrWz9s01 for ; Fri, 29 Jun 2018 16:07:03 +1000 (AEST) Received: from localhost ([::1]:40112 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fYmYf-0003Qa-FE for incoming@patchwork.ozlabs.org; Fri, 29 Jun 2018 02:07:01 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35150) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fYmVZ-00016O-Mc for qemu-devel@nongnu.org; Fri, 29 Jun 2018 02:03:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fYmVY-0007GI-TT for qemu-devel@nongnu.org; Fri, 29 Jun 2018 02:03:49 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:38408 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fYmVW-0007EB-Pi; Fri, 29 Jun 2018 02:03:46 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5B4904059FEC; Fri, 29 Jun 2018 06:03:46 +0000 (UTC) Received: from lemon.usersys.redhat.com (ovpn-12-83.pek2.redhat.com [10.72.12.83]) by smtp.corp.redhat.com (Postfix) with ESMTP id 376757C57; Fri, 29 Jun 2018 06:03:43 +0000 (UTC) From: Fam Zheng To: qemu-devel@nongnu.org Date: Fri, 29 Jun 2018 14:03:28 +0800 Message-Id: <20180629060328.4423-4-famz@redhat.com> In-Reply-To: <20180629060328.4423-1-famz@redhat.com> References: <20180629060328.4423-1-famz@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Fri, 29 Jun 2018 06:03:46 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Fri, 29 Jun 2018 06:03:46 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'famz@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PATCH 3/3] file-posix: Fix EINTR handling X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , qemu-block@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" EINTR should be checked against errno, not ret. While fixing the bug, collect the branches with a switch block. Also, change the return value from -ENOSTUP to -ENOSPC when the actual issue is request range passes EOF, which should be distinguishable from the case of error == ENOSYS by the caller, so that it could still retry with other byte ranges, whereas it shouldn't retry anymore upon ENOSYS. Signed-off-by: Fam Zheng --- block/file-posix.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index 07bb061fe4..6b736f603a 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -1474,20 +1474,21 @@ static ssize_t handle_aiocb_copy_range(RawPosixAIOData *aiocb) ssize_t ret = copy_file_range(aiocb->aio_fildes, &in_off, aiocb->aio_fd2, &out_off, bytes, 0); - if (ret == -EINTR) { - continue; + if (ret == 0) { + /* No progress (e.g. when beyond EOF), let the caller fall back to + * buffer I/O. */ + return -ENOSPC; } if (ret < 0) { - if (errno == ENOSYS) { + switch (errno) { + case ENOSYS: return -ENOTSUP; - } else { + case EINTR: + continue; + default: return -errno; } } - if (!ret) { - /* No progress (e.g. when beyond EOF), fall back to buffer I/O. */ - return -ENOTSUP; - } bytes -= ret; } return 0;