From nobody Tue Dec 16 16:35:52 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (208.118.235.17 [208.118.235.17]) by mx.zohomail.com with SMTPS id 1512589879400688.2465088426464; Wed, 6 Dec 2017 11:51:19 -0800 (PST) Received: from localhost ([::1]:57390 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eMfir-0001d6-JP for importer@patchew.org; Wed, 06 Dec 2017 14:51:13 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49728) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eMfCc-0000tU-2q for qemu-devel@nongnu.org; Wed, 06 Dec 2017 14:17:56 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eMfCZ-0000u2-Mk for qemu-devel@nongnu.org; Wed, 06 Dec 2017 14:17:54 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:50390) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eMfCZ-0000sx-E6 for qemu-devel@nongnu.org; Wed, 06 Dec 2017 14:17:51 -0500 Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id vB6JEb0h013906 for ; Wed, 6 Dec 2017 14:17:50 -0500 Received: from e36.co.us.ibm.com (e36.co.us.ibm.com [32.97.110.154]) by mx0a-001b2d01.pphosted.com with ESMTP id 2epm4274x4-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Wed, 06 Dec 2017 14:17:50 -0500 Received: from localhost by e36.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Wed, 6 Dec 2017 12:17:45 -0700 Received: from b03ledav004.gho.boulder.ibm.com (b03ledav004.gho.boulder.ibm.com [9.17.130.235]) by b03cxnp08028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id vB6JHiA92752974; Wed, 6 Dec 2017 12:17:45 -0700 Received: from b03ledav004.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 52E0E7803F; Wed, 6 Dec 2017 12:17:45 -0700 (MST) Received: from localhost (unknown [9.80.93.86]) by b03ledav004.gho.boulder.ibm.com (Postfix) with ESMTP id 1C4AF78043; Wed, 6 Dec 2017 12:17:44 -0700 (MST) From: Michael Roth To: qemu-devel@nongnu.org Date: Wed, 6 Dec 2017 13:16:34 -0600 X-Mailer: git-send-email 2.11.0 In-Reply-To: <20171206191648.18208-1-mdroth@linux.vnet.ibm.com> References: <20171206191648.18208-1-mdroth@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17120619-0020-0000-0000-00000D1F94AB X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00008161; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000244; SDB=6.00956379; UDB=6.00483442; IPR=6.00736416; BA=6.00005729; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00018387; XFM=3.00000015; UTC=2017-12-06 19:17:47 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17120619-0021-0000-0000-00005F320EC1 Message-Id: <20171206191648.18208-42-mdroth@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-12-06_07:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1712060273 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] X-Received-From: 148.163.156.1 Subject: [Qemu-devel] [PATCH 41/55] virtio: Add queue interface to restore avail index from vring used index 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: Maxime Coquelin , qemu-stable@nongnu.org, "Michael S . Tsirkin" Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" From: Maxime Coquelin In case of backend crash, it is not possible to restore internal avail index from the backend value as vhost_get_vring_base callback fails. This patch provides a new interface to restore internal avail index from the vring used index, as done by some vhost-user backend on reconnection. Signed-off-by: Maxime Coquelin Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin (cherry picked from commit 2d4ba6cc741df15df6fbb4feaa706a02e103083a) Signed-off-by: Michael Roth --- hw/virtio/virtio.c | 10 ++++++++++ include/hw/virtio/virtio.h | 1 + 2 files changed, 11 insertions(+) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 464947f76d..15cf6021a0 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -2311,6 +2311,16 @@ void virtio_queue_set_last_avail_idx(VirtIODevice *v= dev, int n, uint16_t idx) vdev->vq[n].shadow_avail_idx =3D idx; } =20 +void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n) +{ + rcu_read_lock(); + if (vdev->vq[n].vring.desc) { + vdev->vq[n].last_avail_idx =3D vring_used_idx(&vdev->vq[n]); + vdev->vq[n].shadow_avail_idx =3D vdev->vq[n].last_avail_idx; + } + rcu_read_unlock(); +} + void virtio_queue_update_used_idx(VirtIODevice *vdev, int n) { rcu_read_lock(); diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h index 80c45c321e..3d5c84e829 100644 --- a/include/hw/virtio/virtio.h +++ b/include/hw/virtio/virtio.h @@ -272,6 +272,7 @@ hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, = int n); hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n); uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n); void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t i= dx); +void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n); void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n); void virtio_queue_update_used_idx(VirtIODevice *vdev, int n); VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n); --=20 2.11.0