From patchwork Fri Jun 19 18:23:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Eugenio Perez Martin X-Patchwork-Id: 11614897 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3B92E913 for ; Fri, 19 Jun 2020 18:23:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1CBA921527 for ; Fri, 19 Jun 2020 18:23:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="QN/uc4DV" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405981AbgFSSXt (ORCPT ); Fri, 19 Jun 2020 14:23:49 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:20549 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2405620AbgFSSXr (ORCPT ); Fri, 19 Jun 2020 14:23:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592591024; 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=MDyMx/QYjv9YV91ubBW7aVwYK/qJjL8pnhsfMBIV3zE=; b=QN/uc4DVGf2ehT7byYjvpes2yNc3cXCx4tqW7n/KdFx/zePWGmoNtVVWJixkUOGEMkQYDh 0E/sX2X9uX79iCwgOCgd71P9ymeJJcann2HTJHFuDnlgkxa2n2Y0pYBEeLAw/5byAxwlWk Qo9CuTXEfA++PSu8w8MSz05cFbzXmPY= 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-177-nAqeIG35MDOL3vAb7c9CYQ-1; Fri, 19 Jun 2020 14:23:40 -0400 X-MC-Unique: nAqeIG35MDOL3vAb7c9CYQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7D62C8018A5; Fri, 19 Jun 2020 18:23:39 +0000 (UTC) Received: from eperezma.remote.csb (ovpn-113-14.ams2.redhat.com [10.36.113.14]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8A8821C8; Fri, 19 Jun 2020 18:23:37 +0000 (UTC) From: =?utf-8?q?Eugenio_P=C3=A9rez?= To: mst@redhat.com Cc: kvm list , Stefano Garzarella , virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Stefan Hajnoczi , Jason Wang Subject: [RFC v9 09/11] vhost/scsi: switch to buf APIs Date: Fri, 19 Jun 2020 20:23:00 +0200 Message-Id: <20200619182302.850-10-eperezma@redhat.com> In-Reply-To: <20200619182302.850-1-eperezma@redhat.com> References: <20200619182302.850-1-eperezma@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "Michael S. Tsirkin" Switch to buf APIs. Doing this exposes a spec violation in vhost scsi: all used bufs are marked with length 0. Fix that is left for another day. Signed-off-by: Michael S. Tsirkin Signed-off-by: Eugenio Pérez Reviewed-by: Stefan Hajnoczi --- drivers/vhost/scsi.c | 73 ++++++++++++++++++++++++++------------------ 1 file changed, 44 insertions(+), 29 deletions(-) diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index 6fb4d7ecfa19..f09ca5244ab9 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -71,8 +71,8 @@ struct vhost_scsi_inflight { }; struct vhost_scsi_cmd { - /* Descriptor from vhost_get_vq_desc() for virt_queue segment */ - int tvc_vq_desc; + /* Descriptor from vhost_get_avail_buf() for virt_queue segment */ + struct vhost_buf tvc_vq_desc; /* virtio-scsi initiator task attribute */ int tvc_task_attr; /* virtio-scsi response incoming iovecs */ @@ -213,7 +213,7 @@ struct vhost_scsi { * Context for processing request and control queue operations. */ struct vhost_scsi_ctx { - int head; + struct vhost_buf buf; unsigned int out, in; size_t req_size, rsp_size; size_t out_size, in_size; @@ -443,6 +443,20 @@ static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd) return target_put_sess_cmd(se_cmd); } +/* Signal to guest that request finished with no input buffer. */ +/* TODO calling this when writing into buffer and most likely a bug */ +static void vhost_scsi_signal_noinput(struct vhost_dev *vdev, + struct vhost_virtqueue *vq, + struct vhost_buf *bufp) +{ + struct vhost_buf buf = *bufp; + + buf.in_len = 0; + vhost_put_used_buf(vq, &buf); + vhost_signal(vdev, vq); +} + + static void vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt) { @@ -450,7 +464,8 @@ vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt) struct virtio_scsi_event *event = &evt->event; struct virtio_scsi_event __user *eventp; unsigned out, in; - int head, ret; + struct vhost_buf buf; + int ret; if (!vhost_vq_get_backend(vq)) { vs->vs_events_missed = true; @@ -459,14 +474,14 @@ vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt) again: vhost_disable_notify(&vs->dev, vq); - head = vhost_get_vq_desc(vq, vq->iov, - ARRAY_SIZE(vq->iov), &out, &in, - NULL, NULL); - if (head < 0) { + ret = vhost_get_avail_buf(vq, &buf, + vq->iov, ARRAY_SIZE(vq->iov), &out, &in, + NULL, NULL); + if (ret < 0) { vs->vs_events_missed = true; return; } - if (head == vq->num) { + if (!ret) { if (vhost_enable_notify(&vs->dev, vq)) goto again; vs->vs_events_missed = true; @@ -488,7 +503,7 @@ vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt) eventp = vq->iov[out].iov_base; ret = __copy_to_user(eventp, event, sizeof(*event)); if (!ret) - vhost_add_used_and_signal(&vs->dev, vq, head, 0); + vhost_scsi_signal_noinput(&vs->dev, vq, &buf); else vq_err(vq, "Faulted on vhost_scsi_send_event\n"); } @@ -549,7 +564,7 @@ static void vhost_scsi_complete_cmd_work(struct vhost_work *work) ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter); if (likely(ret == sizeof(v_rsp))) { struct vhost_scsi_virtqueue *q; - vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0); + vhost_put_used_buf(cmd->tvc_vq, &cmd->tvc_vq_desc); q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq); vq = q - vs->vqs; __set_bit(vq, signal); @@ -793,7 +808,7 @@ static void vhost_scsi_submission_work(struct work_struct *work) static void vhost_scsi_send_bad_target(struct vhost_scsi *vs, struct vhost_virtqueue *vq, - int head, unsigned out) + struct vhost_buf *buf, unsigned out) { struct virtio_scsi_cmd_resp __user *resp; struct virtio_scsi_cmd_resp rsp; @@ -804,7 +819,7 @@ vhost_scsi_send_bad_target(struct vhost_scsi *vs, resp = vq->iov[out].iov_base; ret = __copy_to_user(resp, &rsp, sizeof(rsp)); if (!ret) - vhost_add_used_and_signal(&vs->dev, vq, head, 0); + vhost_scsi_signal_noinput(&vs->dev, vq, buf); else pr_err("Faulted on virtio_scsi_cmd_resp\n"); } @@ -813,21 +828,21 @@ static int vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc) { - int ret = -ENXIO; + int r, ret = -ENXIO; - vc->head = vhost_get_vq_desc(vq, vq->iov, - ARRAY_SIZE(vq->iov), &vc->out, &vc->in, - NULL, NULL); + r = vhost_get_avail_buf(vq, &vc->buf, + vq->iov, ARRAY_SIZE(vq->iov), &vc->out, &vc->in, + NULL, NULL); - pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n", - vc->head, vc->out, vc->in); + pr_debug("vhost_get_avail_buf: buf: %d, out: %u in: %u\n", + vc->buf.id, vc->out, vc->in); /* On error, stop handling until the next kick. */ - if (unlikely(vc->head < 0)) + if (unlikely(r < 0)) goto done; /* Nothing new? Wait for eventfd to tell us they refilled. */ - if (vc->head == vq->num) { + if (!r) { if (unlikely(vhost_enable_notify(&vs->dev, vq))) { vhost_disable_notify(&vs->dev, vq); ret = -EAGAIN; @@ -1093,11 +1108,11 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) } } /* - * Save the descriptor from vhost_get_vq_desc() to be used to + * Save the descriptor from vhost_get_avail_buf() to be used to * complete the virtio-scsi request in TCM callback context via * vhost_scsi_queue_data_in() and vhost_scsi_queue_status() */ - cmd->tvc_vq_desc = vc.head; + cmd->tvc_vq_desc = vc.buf; /* * Dispatch cmd descriptor for cmwq execution in process * context provided by vhost_scsi_workqueue. This also ensures @@ -1117,7 +1132,7 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) if (ret == -ENXIO) break; else if (ret == -EIO) - vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out); + vhost_scsi_send_bad_target(vs, vq, &vc.buf, vc.out); } while (likely(!vhost_exceeds_weight(vq, ++c, 0))); out: mutex_unlock(&vq->mutex); @@ -1139,9 +1154,9 @@ vhost_scsi_send_tmf_reject(struct vhost_scsi *vs, iov_iter_init(&iov_iter, READ, &vq->iov[vc->out], vc->in, sizeof(rsp)); ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter); - if (likely(ret == sizeof(rsp))) - vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0); - else + if (likely(ret == sizeof(rsp))) { + vhost_scsi_signal_noinput(&vs->dev, vq, &vc->buf); + } else pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n"); } @@ -1162,7 +1177,7 @@ vhost_scsi_send_an_resp(struct vhost_scsi *vs, ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter); if (likely(ret == sizeof(rsp))) - vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0); + vhost_scsi_signal_noinput(&vs->dev, vq, &vc->buf); else pr_err("Faulted on virtio_scsi_ctrl_an_resp\n"); } @@ -1269,7 +1284,7 @@ vhost_scsi_ctl_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) if (ret == -ENXIO) break; else if (ret == -EIO) - vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out); + vhost_scsi_send_bad_target(vs, vq, &vc.buf, vc.out); } while (likely(!vhost_exceeds_weight(vq, ++c, 0))); out: mutex_unlock(&vq->mutex);