vhost_scsi: support initiators without eventq/controlq

Change-Id: I400edd6d6f71de005b3ccbe9968631a067226035
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/408611
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Pawel Wodkowski <pawelx.wodkowski@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>

lib/vhost/rte_vhost/rte_vhost.h

@@ -349,34 +349,6 @@ int rte_vhost_get_mtu(int vid, uint16_t *mtu);
  */
 int rte_vhost_get_numa_node(int vid);
 
-/**
- * @deprecated
- * Get the number of queues the device supports.
- *
- * Note this function is deprecated, as it returns a queue pair number,
- * which is vhost specific. Instead, rte_vhost_get_vring_num should
- * be used.
- *
- * @param vid
- *  vhost device ID
- *
- * @return
- *  The number of queues, 0 on failure
- */
-__rte_deprecated
-uint32_t rte_vhost_get_queue_num(int vid);
-
-/**
- * Get the number of vrings the device supports.
- *
- * @param vid
- *  vhost device ID
- *
- * @return
- *  The number of vrings, 0 on failure
- */
-uint16_t rte_vhost_get_vring_num(int vid);
-
 /**
  * Get the virtio net device's ifname, which is the vhost-user socket
  * file path.

lib/vhost/rte_vhost/vhost.c

@@ -307,28 +307,6 @@ rte_vhost_get_numa_node(int vid)
 #endif
 }
 
-uint32_t
-rte_vhost_get_queue_num(int vid)
-{
-	struct virtio_net *dev = get_device(vid);
-
-	if (dev == NULL)
-		return 0;
-
-	return dev->nr_vring / 2;
-}
-
-uint16_t
-rte_vhost_get_vring_num(int vid)
-{
-	struct virtio_net *dev = get_device(vid);
-
-	if (dev == NULL)
-		return 0;
-
-	return dev->nr_vring;
-}
-
 int
 rte_vhost_get_ifname(int vid, char *buf, size_t len)
 {

lib/vhost/rte_vhost/vhost_user.c

@@ -716,13 +716,14 @@ virtio_is_ready(struct virtio_net *dev)
 	for (i = 0; i < dev->nr_vring; i++) {
 		vq = dev->virtqueue[i];
 
-		if (!vq_is_ready(vq))
+		if (vq_is_ready(vq)) {
-			return 0;
-	}
-
 			RTE_LOG(INFO, VHOST_CONFIG,
 				"virtio is now ready for processing.\n");
 			return 1;
+		}
+	}
+
+	return 0;
 }
 
 static void

lib/vhost/vhost.c

@@ -275,7 +275,7 @@ check_dev_io_stats(struct spdk_vhost_dev *vdev, uint64_t now)
 	}
 
 	vdev->next_stats_check_time = now + vdev->stats_check_interval;
-	for (q_idx = 0; q_idx < vdev->num_queues; q_idx++) {
+	for (q_idx = 0; q_idx < vdev->max_queues; q_idx++) {
 		virtqueue = &vdev->virtqueue[q_idx];
 
 		req_cnt = virtqueue->req_cnt + virtqueue->used_req_cnt;
@@ -299,10 +299,11 @@ spdk_vhost_dev_used_signal(struct spdk_vhost_dev *vdev)
 	uint16_t q_idx;
 
 	if (vdev->coalescing_delay_time_base == 0) {
-		for (q_idx = 0; q_idx < vdev->num_queues; q_idx++) {
+		for (q_idx = 0; q_idx < vdev->max_queues; q_idx++) {
 			virtqueue = &vdev->virtqueue[q_idx];
 
-			if (virtqueue->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT) {
+			if (virtqueue->vring.desc == NULL ||
+			    (virtqueue->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)) {
 				continue;
 			}
 
@@ -312,7 +313,7 @@ spdk_vhost_dev_used_signal(struct spdk_vhost_dev *vdev)
 		now = spdk_get_ticks();
 		check_dev_io_stats(vdev, now);
 
-		for (q_idx = 0; q_idx < vdev->num_queues; q_idx++) {
+		for (q_idx = 0; q_idx < vdev->max_queues; q_idx++) {
 			virtqueue = &vdev->virtqueue[q_idx];
 
 			/* No need for event right now */
@@ -987,8 +988,11 @@ stop_device(int vid)
 		return;
 	}
 
-	for (i = 0; i < vdev->num_queues; i++) {
+	for (i = 0; i < vdev->max_queues; i++) {
 		q = &vdev->virtqueue[i].vring;
+		if (q->desc == NULL) {
+			continue;
+		}
 		rte_vhost_set_vhost_vring_last_idx(vdev->vid, i, q->last_avail_idx, q->last_used_idx);
 	}
 
@@ -1004,11 +1008,9 @@ start_device(int vid)
 {
 	struct spdk_vhost_dev *vdev;
 	int rc = -1;
-	uint16_t num_queues;
 	uint16_t i;
 
 	pthread_mutex_lock(&g_spdk_vhost_mutex);
-	num_queues = rte_vhost_get_vring_num(vid);
 
 	vdev = spdk_vhost_dev_find_by_vid(vid);
 	if (vdev == NULL) {
@@ -1021,22 +1023,16 @@ start_device(int vid)
 		goto out;
 	}
 
-	if (num_queues > SPDK_VHOST_MAX_VQUEUES) {
+	vdev->max_queues = 0;
-		SPDK_ERRLOG("vhost device %d: Too many queues (%"PRIu16"). Max %"PRIu16"\n", vid, num_queues,
-			    SPDK_VHOST_MAX_VQUEUES);
-		goto out;
-	}
-
 	memset(vdev->virtqueue, 0, sizeof(vdev->virtqueue));
-	for (i = 0; i < num_queues; i++) {
+	for (i = 0; i < SPDK_VHOST_MAX_VQUEUES; i++) {
 		if (rte_vhost_get_vhost_vring(vid, i, &vdev->virtqueue[i].vring)) {
-			SPDK_ERRLOG("vhost device %d: Failed to get information of queue %"PRIu16"\n", vid, i);
+			continue;
-			goto out;
 		}
 
-		if (vdev->virtqueue[i].vring.size == 0) {
+		if (vdev->virtqueue[i].vring.desc == NULL ||
-			SPDK_ERRLOG("vhost device %d: Queue %"PRIu16" has size 0.\n", vid, i);
+		    vdev->virtqueue[i].vring.size == 0) {
-			goto out;
+			continue;
 		}
 
 		/* Disable notifications. */
@@ -1044,9 +1040,9 @@ start_device(int vid)
 			SPDK_ERRLOG("vhost device %d: Failed to disable guest notification on queue %"PRIu16"\n", vid, i);
 			goto out;
 		}
-	}
 
-	vdev->num_queues = num_queues;
+		vdev->max_queues = i + 1;
+	}
 
 	if (rte_vhost_get_negotiated_features(vid, &vdev->negotiated_features) != 0) {
 		SPDK_ERRLOG("vhost device %d: Failed to get negotiated driver features\n", vid);
@@ -1067,7 +1063,7 @@ start_device(int vid)
 	 *
 	 * Tested on QEMU 2.10.91 and 2.11.50.
 	 */
-	for (i = 0; i < num_queues; i++) {
+	for (i = 0; i < vdev->max_queues; i++) {
 		if (vdev->virtqueue[i].vring.callfd != -1) {
 			eventfd_write(vdev->virtqueue[i].vring.callfd, (eventfd_t)1);
 		}

lib/vhost/vhost_blk.c

@@ -333,7 +333,7 @@ vdev_worker(void *arg)
 	struct spdk_vhost_blk_dev *bvdev = arg;
 	uint16_t q_idx;
 
-	for (q_idx = 0; q_idx < bvdev->vdev.num_queues; q_idx++) {
+	for (q_idx = 0; q_idx < bvdev->vdev.max_queues; q_idx++) {
 		process_vq(bvdev, &bvdev->vdev.virtqueue[q_idx]);
 	}
 
@@ -368,7 +368,7 @@ no_bdev_vdev_worker(void *arg)
 	struct spdk_vhost_blk_dev *bvdev = arg;
 	uint16_t q_idx;
 
-	for (q_idx = 0; q_idx < bvdev->vdev.num_queues; q_idx++) {
+	for (q_idx = 0; q_idx < bvdev->vdev.max_queues; q_idx++) {
 		no_bdev_process_vq(bvdev, &bvdev->vdev.virtqueue[q_idx]);
 	}
 
@@ -433,7 +433,7 @@ free_task_pool(struct spdk_vhost_blk_dev *bvdev)
 	struct spdk_vhost_virtqueue *vq;
 	uint16_t i;
 
-	for (i = 0; i < bvdev->vdev.num_queues; i++) {
+	for (i = 0; i < bvdev->vdev.max_queues; i++) {
 		vq = &bvdev->vdev.virtqueue[i];
 		if (vq->tasks == NULL) {
 			continue;
@@ -453,8 +453,12 @@ alloc_task_pool(struct spdk_vhost_blk_dev *bvdev)
 	uint16_t i;
 	uint32_t j;
 
-	for (i = 0; i < bvdev->vdev.num_queues; i++) {
+	for (i = 0; i < bvdev->vdev.max_queues; i++) {
 		vq = &bvdev->vdev.virtqueue[i];
+		if (vq->vring.desc == NULL) {
+			continue;
+		}
+
 		task_cnt = vq->vring.size;
 		if (task_cnt > SPDK_VHOST_MAX_VQ_SIZE) {
 			/* sanity check */
@@ -492,7 +496,7 @@ static int
 spdk_vhost_blk_start(struct spdk_vhost_dev *vdev, void *event_ctx)
 {
 	struct spdk_vhost_blk_dev *bvdev;
-	int rc = 0;
+	int i, rc = 0;
 
 	bvdev = to_blk_dev(vdev);
 	if (bvdev == NULL) {
@@ -501,6 +505,15 @@ spdk_vhost_blk_start(struct spdk_vhost_dev *vdev, void *event_ctx)
 		goto out;
 	}
 
+	/* validate all I/O queues are in a contiguous index range */
+	for (i = 0; i < vdev->max_queues; i++) {
+		if (vdev->virtqueue[i].vring.desc == NULL) {
+			SPDK_ERRLOG("%s: queue %"PRIu32" is empty\n", vdev->name, i);
+			rc = -1;
+			goto out;
+		}
+	}
+
 	rc = alloc_task_pool(bvdev);
 	if (rc != 0) {
 		SPDK_ERRLOG("%s: failed to alloc task pool.\n", bvdev->vdev.name);
@@ -542,7 +555,7 @@ destroy_device_poller_cb(void *arg)
 		return -1;
 	}
 
-	for (i = 0; i < bvdev->vdev.num_queues; i++) {
+	for (i = 0; i < bvdev->vdev.max_queues; i++) {
 		bvdev->vdev.virtqueue[i].next_event_time = 0;
 		spdk_vhost_vq_used_signal(&bvdev->vdev, &bvdev->vdev.virtqueue[i]);
 	}

lib/vhost/vhost_internal.h

@@ -161,7 +161,7 @@ struct spdk_vhost_dev {
 	/* Interval used for event coalescing checking. */
 	uint64_t stats_check_interval;
 
-	uint16_t num_queues;
+	uint16_t max_queues;
 
 	uint64_t negotiated_features;
 

lib/vhost/vhost_scsi.c

@@ -670,7 +670,7 @@ vdev_worker(void *arg)
 	struct spdk_vhost_scsi_dev *svdev = arg;
 	uint32_t q_idx;
 
-	for (q_idx = VIRTIO_SCSI_REQUESTQ; q_idx < svdev->vdev.num_queues; q_idx++) {
+	for (q_idx = VIRTIO_SCSI_REQUESTQ; q_idx < svdev->vdev.max_queues; q_idx++) {
 		process_requestq(svdev, &svdev->vdev.virtqueue[q_idx]);
 	}
 
@@ -1006,7 +1006,7 @@ free_task_pool(struct spdk_vhost_scsi_dev *svdev)
 	struct spdk_vhost_virtqueue *vq;
 	uint16_t i;
 
-	for (i = 0; i < svdev->vdev.num_queues; i++) {
+	for (i = 0; i < svdev->vdev.max_queues; i++) {
 		vq = &svdev->vdev.virtqueue[i];
 		if (vq->tasks == NULL) {
 			continue;
@@ -1026,8 +1026,12 @@ alloc_task_pool(struct spdk_vhost_scsi_dev *svdev)
 	uint16_t i;
 	uint32_t j;
 
-	for (i = 0; i < svdev->vdev.num_queues; i++) {
+	for (i = 0; i < svdev->vdev.max_queues; i++) {
 		vq = &svdev->vdev.virtqueue[i];
+		if (vq->vring.desc == NULL) {
+			continue;
+		}
+
 		task_cnt = vq->vring.size;
 		if (task_cnt > SPDK_VHOST_MAX_VQ_SIZE) {
 			/* sanity check */
@@ -1074,6 +1078,15 @@ spdk_vhost_scsi_start(struct spdk_vhost_dev *vdev, void *event_ctx)
 		goto out;
 	}
 
+	/* validate all I/O queues are in a contiguous index range */
+	for (i = VIRTIO_SCSI_REQUESTQ; i < vdev->max_queues; i++) {
+		if (vdev->virtqueue[i].vring.desc == NULL) {
+			SPDK_ERRLOG("%s: queue %"PRIu32" is empty\n", vdev->name, i);
+			rc = -1;
+			goto out;
+		}
+	}
+
 	rc = alloc_task_pool(svdev);
 	if (rc != 0) {
 		SPDK_ERRLOG("%s: failed to alloc task pool.\n", vdev->name);
@@ -1090,8 +1103,11 @@ spdk_vhost_scsi_start(struct spdk_vhost_dev *vdev, void *event_ctx)
 		     vdev->name, vdev->lcore);
 
 	svdev->requestq_poller = spdk_poller_register(vdev_worker, svdev, 0);
+	if (vdev->virtqueue[VIRTIO_SCSI_CONTROLQ].vring.desc &&
+	    vdev->virtqueue[VIRTIO_SCSI_EVENTQ].vring.desc) {
 		svdev->mgmt_poller = spdk_poller_register(vdev_mgmt_worker, svdev,
 				     MGMT_POLL_PERIOD_US);
+	}
 out:
 	spdk_vhost_dev_backend_event_done(event_ctx, rc);
 	return rc;
@@ -1115,7 +1131,7 @@ destroy_device_poller_cb(void *arg)
 	}
 
 
-	for (i = 0; i < svdev->vdev.num_queues; i++) {
+	for (i = 0; i < svdev->vdev.max_queues; i++) {
 		spdk_vhost_vq_used_signal(&svdev->vdev, &svdev->vdev.virtqueue[i]);
 	}