From nobody Wed Apr 16 08:59:57 2025 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1685633233; cv=none; d=zohomail.com; s=zohoarc; b=EPQ2iGhcMeE/Si/VxHLU71HfWpPQU8O70zx1Vw0l8mB29WS6iR25XzqvUyp0XFFNWti6Lc1IFnoalJAXpt63N1gzuHE9vct92fAW+Ri4VbZHO3uIs/y88W3nAFWOu8X4LX1gjsepq5DBw8OqnnbT0P2dx63ABsQCS9gdZmNseas= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1685633233; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=+2jIiSec093zxYLQEOwE5JssP3b16O/dNh3vcZRftBM=; b=jmrhmlUQ8BCmYUt3U3P330+T9Tscsw41GPsiRI6UkXK4IOdtUElFRKz/Bsbamwvs3dUMSRm9y/o51mBrbo6pWjfqV+edNGdKZhspwNjLJIy6xIeREUbNw9vtGUfp7XsDRHG7uafXxcyTvCSs9tIoEJQj2KtdgubR23EiVzTVg+E= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 16856332334121013.6744258894354; Thu, 1 Jun 2023 08:27:13 -0700 (PDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1q4kC8-0004bZ-Q8; Thu, 01 Jun 2023 11:26:32 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q4kC7-0004ah-FK for qemu-devel@nongnu.org; Thu, 01 Jun 2023 11:26:31 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q4kBr-0003VB-GT for qemu-devel@nongnu.org; Thu, 01 Jun 2023 11:26:31 -0400 Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-341-uDT_KEXNMA2D1W8fWckpaA-1; Thu, 01 Jun 2023 11:26:10 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4B4333823A15; Thu, 1 Jun 2023 15:26:09 +0000 (UTC) Received: from localhost (unknown [10.39.194.5]) by smtp.corp.redhat.com (Postfix) with ESMTP id A8F5A112132C; Thu, 1 Jun 2023 15:26:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1685633173; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=+2jIiSec093zxYLQEOwE5JssP3b16O/dNh3vcZRftBM=; b=D5SvOMUkQYxtKKuoo7d8aPj1lek+3p1KfQlEkt5E3FSWFl3luku9Mtw9Q/NLYnfOBESB/D HsOcGe2Bp/EYNwpf1dDt4Eb28xn4OkWr0JaG2a0UXOOYSDqlPpoGlgtKwX8pR9XTNItigK nDU2gQurIdbJSFMCw2jBbbx2fwG4oFI= X-MC-Unique: uDT_KEXNMA2D1W8fWckpaA-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: qemu-block@nongnu.org, Stefano Stabellini , Aarushi Mehta , Anthony Perard , Thomas Huth , Julia Suvorova , Paolo Bonzini , Fam Zheng , Hanna Reitz , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Stefano Garzarella , "Michael S. Tsirkin" , =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= , Markus Armbruster , Cornelia Huck , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , xen-devel@lists.xenproject.org, Paul Durrant , Kevin Wolf , Richard Henderson , Eric Blake , Stefan Hajnoczi , Raphael Norwitz , kvm@vger.kernel.org Subject: [PULL 7/8] block/blkio: use qemu_open() to support fd passing for virtio-blk Date: Thu, 1 Jun 2023 11:25:51 -0400 Message-Id: <20230601152552.1603119-8-stefanha@redhat.com> In-Reply-To: <20230601152552.1603119-1-stefanha@redhat.com> References: <20230601152552.1603119-1-stefanha@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -22 X-Spam_score: -2.3 X-Spam_bar: -- X-Spam_report: (-2.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.166, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1685633234942100007 Content-Type: text/plain; charset="utf-8" From: Stefano Garzarella Some virtio-blk drivers (e.g. virtio-blk-vhost-vdpa) supports the fd passing. Let's expose this to the user, so the management layer can pass the file descriptor of an already opened path. If the libblkio virtio-blk driver supports fd passing, let's always use qemu_open() to open the `path`, so we can handle fd passing from the management layer through the "/dev/fdset/N" special path. Reviewed-by: Stefan Hajnoczi Signed-off-by: Stefano Garzarella Message-id: 20230530071941.8954-2-sgarzare@redhat.com Signed-off-by: Stefan Hajnoczi --- block/blkio.c | 53 ++++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 44 insertions(+), 9 deletions(-) diff --git a/block/blkio.c b/block/blkio.c index 11be8787a3..527323d625 100644 --- a/block/blkio.c +++ b/block/blkio.c @@ -673,25 +673,60 @@ static int blkio_virtio_blk_common_open(BlockDriverSt= ate *bs, { const char *path =3D qdict_get_try_str(options, "path"); BDRVBlkioState *s =3D bs->opaque; - int ret; + bool fd_supported =3D false; + int fd, ret; =20 if (!path) { error_setg(errp, "missing 'path' option"); return -EINVAL; } =20 - ret =3D blkio_set_str(s->blkio, "path", path); - qdict_del(options, "path"); - if (ret < 0) { - error_setg_errno(errp, -ret, "failed to set path: %s", - blkio_get_error_msg()); - return ret; - } - if (!(flags & BDRV_O_NOCACHE)) { error_setg(errp, "cache.direct=3Doff is not supported"); return -EINVAL; } + + if (blkio_get_int(s->blkio, "fd", &fd) =3D=3D 0) { + fd_supported =3D true; + } + + /* + * If the libblkio driver supports fd passing, let's always use qemu_o= pen() + * to open the `path`, so we can handle fd passing from the management + * layer through the "/dev/fdset/N" special path. + */ + if (fd_supported) { + int open_flags; + + if (flags & BDRV_O_RDWR) { + open_flags =3D O_RDWR; + } else { + open_flags =3D O_RDONLY; + } + + fd =3D qemu_open(path, open_flags, errp); + if (fd < 0) { + return -EINVAL; + } + + ret =3D blkio_set_int(s->blkio, "fd", fd); + if (ret < 0) { + error_setg_errno(errp, -ret, "failed to set fd: %s", + blkio_get_error_msg()); + qemu_close(fd); + return ret; + } + } else { + ret =3D blkio_set_str(s->blkio, "path", path); + if (ret < 0) { + error_setg_errno(errp, -ret, "failed to set path: %s", + blkio_get_error_msg()); + return ret; + } + } + + qdict_del(options, "path"); + return 0; } =20 --=20 2.40.1