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=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 2CB05C433E0 for ; Tue, 16 Feb 2021 18:48:53 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BEC3664EC0 for ; Tue, 16 Feb 2021 18:48:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BEC3664EC0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:57886 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lC5P1-00039w-Oq for qemu-devel@archiver.kernel.org; Tue, 16 Feb 2021 13:48:51 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:37036) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lC5EW-0004Nm-TG for qemu-devel@nongnu.org; Tue, 16 Feb 2021 13:38:01 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:51843) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1lC5EU-0000Hf-3v for qemu-devel@nongnu.org; Tue, 16 Feb 2021 13:38:00 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1613500677; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ly6cDLLcovd5j+qUNv0TPyzTE/C95+IKsT5ZzEfVeCw=; b=WPJZVBAj0oorGsluzmkZ4XhVXUOo2QPkh+SP6QgRGuz4ZMyModGl/MZ0PEX3UhFHq39gY+ x/ECrBESfVVH7BEGhkJLhiI0/cdvRa2uysGB7HVS26w09xitweGrgGywaerQ+L3gTrmohE fG6bLG3T+ScUw+ZBXk7l6LElsMiQOTo= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-34-Kl0pVALBN9CTnRKxjPNqLg-1; Tue, 16 Feb 2021 13:37:53 -0500 X-MC-Unique: Kl0pVALBN9CTnRKxjPNqLg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D287F6EE20; Tue, 16 Feb 2021 18:37:52 +0000 (UTC) Received: from dgilbert-t580.localhost (ovpn-115-109.ams2.redhat.com [10.36.115.109]) by smtp.corp.redhat.com (Postfix) with ESMTP id A57F55C1B4; Tue, 16 Feb 2021 18:37:48 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, wainersm@redhat.com, groug@kaod.org, philmd@redhat.com, vgoyal@redhat.com Subject: [PULL 4/6] virtiofsd: Save error code early at the failure callsite Date: Tue, 16 Feb 2021 18:37:32 +0000 Message-Id: <20210216183734.57810-5-dgilbert@redhat.com> In-Reply-To: <20210216183734.57810-1-dgilbert@redhat.com> References: <20210216183734.57810-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Received-SPF: pass client-ip=170.10.133.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: virtio-fs@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Vivek Goyal Change error code handling slightly in lo_setattr(). Right now we seem to jump to out_err and assume that "errno" is valid and use that to send reply. But if caller has to do some other operations before jumping to out_err, then it does the dance of first saving errno to saverr and the restore errno before jumping to out_err. This makes it more confusing. I am about to make more changes where caller will have to do some work after error before jumping to out_err. I found it easier to change the convention a bit. That is caller saves error in "saverr" before jumping to out_err. And out_err uses "saverr" to send error back and does not rely on "errno" having actual error. v3: Resolved conflicts in lo_setattr() due to lo_inode_open() changes. Signed-off-by: Vivek Goyal Reviewed-by: Dr. David Alan Gilbert Message-Id: <20210208224024.43555-2-vgoyal@redhat.com> Signed-off-by: Dr. David Alan Gilbert --- tools/virtiofsd/passthrough_ll.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c index 5f3afe8557..216c0bc026 100644 --- a/tools/virtiofsd/passthrough_ll.c +++ b/tools/virtiofsd/passthrough_ll.c @@ -698,6 +698,7 @@ static void lo_setattr(fuse_req_t req, fuse_ino_t ino, struct stat *attr, res = fchmodat(lo->proc_self_fd, procname, attr->st_mode, 0); } if (res == -1) { + saverr = errno; goto out_err; } } @@ -707,6 +708,7 @@ static void lo_setattr(fuse_req_t req, fuse_ino_t ino, struct stat *attr, res = fchownat(ifd, "", uid, gid, AT_EMPTY_PATH | AT_SYMLINK_NOFOLLOW); if (res == -1) { + saverr = errno; goto out_err; } } @@ -718,16 +720,15 @@ static void lo_setattr(fuse_req_t req, fuse_ino_t ino, struct stat *attr, } else { truncfd = lo_inode_open(lo, inode, O_RDWR); if (truncfd < 0) { - errno = -truncfd; + saverr = -truncfd; goto out_err; } } res = ftruncate(truncfd, attr->st_size); + saverr = res == -1 ? errno : 0; if (!fi) { - saverr = errno; close(truncfd); - errno = saverr; } if (res == -1) { goto out_err; @@ -760,6 +761,7 @@ static void lo_setattr(fuse_req_t req, fuse_ino_t ino, struct stat *attr, res = utimensat(lo->proc_self_fd, procname, tv, 0); } if (res == -1) { + saverr = errno; goto out_err; } } @@ -768,7 +770,6 @@ static void lo_setattr(fuse_req_t req, fuse_ino_t ino, struct stat *attr, return lo_getattr(req, ino, fi); out_err: - saverr = errno; lo_inode_put(lo, &inode); fuse_reply_err(req, saverr); } -- 2.29.2