Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:

- A huge patchset supporting vq resize using the new vq reset
capability

- Features, fixes, and cleanups all over the place

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (88 commits)
vdpa/mlx5: Fix possible uninitialized return value
vdpa_sim_blk: add support for discard and write-zeroes
vdpa_sim_blk: add support for VIRTIO_BLK_T_FLUSH
vdpa_sim_blk: make vdpasim_blk_check_range usable by other requests
vdpa_sim_blk: check if sector is 0 for commands other than read or write
vdpa_sim: Implement suspend vdpa op
vhost-vdpa: uAPI to suspend the device
vhost-vdpa: introduce SUSPEND backend feature bit
vdpa: Add suspend operation
virtio-blk: Avoid use-after-free on suspend/resume
virtio_vdpa: support the arg sizes of find_vqs()
vhost-vdpa: Call ida_simple_remove() when failed
vDPA: fix 'cast to restricted le16' warnings in vdpa.c
vDPA: !FEATURES_OK should not block querying device config space
vDPA/ifcvf: support userspace to query features and MQ of a management device
vDPA/ifcvf: get_config_size should return a value no greater than dev implementation
vhost scsi: Allow user to control num virtqueues
vhost-scsi: Fix max number of virtqueues
vdpa/mlx5: Support different address spaces for control and data
vdpa/mlx5: Implement susupend virtqueue callback
...

Documentation/devicetree/bindings/virtio/mmio.yaml

···
     description: Required for devices making accesses thru an IOMMU.
     maxItems: 1
 
+  wakeup-source:
+    type: boolean
+    description: Required for setting irq of a virtio_mmio device as wakeup source.
+
 required:
   - compatible
   - reg

arch/um/drivers/virtio_uml.c

···
 		goto error_create;
 	}
 	vq->priv = info;
+	vq->num_max = num;
 	num = virtqueue_get_vring_size(vq);
 
 	if (vu_dev->protocol_features &
···
 
 static int vu_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 		       struct virtqueue *vqs[], vq_callback_t *callbacks[],
-		       const char * const names[], const bool *ctx,
+		       const char * const names[], u32 sizes[], const bool *ctx,
 		       struct irq_affinity *desc)
 {
 	struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev);

drivers/block/virtio_blk.c

···
 	}
 }
 
+static inline struct virtio_blk_vq *get_virtio_blk_vq(struct blk_mq_hw_ctx *hctx)
+{
+	struct virtio_blk *vblk = hctx->queue->queuedata;
+	struct virtio_blk_vq *vq = &vblk->vqs[hctx->queue_num];
+
+	return vq;
+}
+
 static int virtblk_add_req(struct virtqueue *vq, struct virtblk_req *vbr)
 {
 	struct scatterlist hdr, status, *sgs[3];
···
 	struct request *requeue_list = NULL;
 
 	rq_list_for_each_safe(rqlist, req, next) {
-		struct virtio_blk_vq *vq = req->mq_hctx->driver_data;
+		struct virtio_blk_vq *vq = get_virtio_blk_vq(req->mq_hctx);
 		bool kick;
 
 		if (!virtblk_prep_rq_batch(req)) {
···
 static int virtblk_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob)
 {
 	struct virtio_blk *vblk = hctx->queue->queuedata;
-	struct virtio_blk_vq *vq = hctx->driver_data;
+	struct virtio_blk_vq *vq = get_virtio_blk_vq(hctx);
 	struct virtblk_req *vbr;
 	unsigned long flags;
 	unsigned int len;
···
 	return found;
 }
 
-static int virtblk_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
-			  unsigned int hctx_idx)
-{
-	struct virtio_blk *vblk = data;
-	struct virtio_blk_vq *vq = &vblk->vqs[hctx_idx];
-
-	WARN_ON(vblk->tag_set.tags[hctx_idx] != hctx->tags);
-	hctx->driver_data = vq;
-	return 0;
-}
-
 static const struct blk_mq_ops virtio_mq_ops = {
 	.queue_rq	= virtio_queue_rq,
 	.queue_rqs	= virtio_queue_rqs,
 	.commit_rqs	= virtio_commit_rqs,
-	.init_hctx	= virtblk_init_hctx,
 	.complete	= virtblk_request_done,
 	.map_queues	= virtblk_map_queues,
 	.poll		= virtblk_poll,

drivers/net/virtio_net.c

···
 	struct virtnet_sq_stats stats;
 
 	struct napi_struct napi;
+
+	/* Record whether sq is in reset state. */
+	bool reset;
 };
 
 /* Internal representation of a receive virtqueue */
···
 	u8 duplex;
 	u32 speed;
 
+	/* Interrupt coalescing settings */
+	u32 tx_usecs;
+	u32 rx_usecs;
+	u32 tx_max_packets;
+	u32 rx_max_packets;
+
 	unsigned long guest_offloads;
 	unsigned long guest_offloads_capable;
 
···
 	 */
 	char padding[12];
 };
+
+static void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf);
+static void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf);
 
 static bool is_xdp_frame(void *ptr)
 {
···
 		return;
 
 	if (__netif_tx_trylock(txq)) {
+		if (sq->reset) {
+			__netif_tx_unlock(txq);
+			return;
+		}
+
 		do {
 			virtqueue_disable_cb(sq->vq);
 			free_old_xmit_skbs(sq, true);
···
 	}
 
 	return NETDEV_TX_OK;
+}
+
+static int virtnet_rx_resize(struct virtnet_info *vi,
+			     struct receive_queue *rq, u32 ring_num)
+{
+	bool running = netif_running(vi->dev);
+	int err, qindex;
+
+	qindex = rq - vi->rq;
+
+	if (running)
+		napi_disable(&rq->napi);
+
+	err = virtqueue_resize(rq->vq, ring_num, virtnet_rq_free_unused_buf);
+	if (err)
+		netdev_err(vi->dev, "resize rx fail: rx queue index: %d err: %d\n", qindex, err);
+
+	if (!try_fill_recv(vi, rq, GFP_KERNEL))
+		schedule_delayed_work(&vi->refill, 0);
+
+	if (running)
+		virtnet_napi_enable(rq->vq, &rq->napi);
+	return err;
+}
+
+static int virtnet_tx_resize(struct virtnet_info *vi,
+			     struct send_queue *sq, u32 ring_num)
+{
+	bool running = netif_running(vi->dev);
+	struct netdev_queue *txq;
+	int err, qindex;
+
+	qindex = sq - vi->sq;
+
+	if (running)
+		virtnet_napi_tx_disable(&sq->napi);
+
+	txq = netdev_get_tx_queue(vi->dev, qindex);
+
+	/* 1. wait all ximt complete
+	 * 2. fix the race of netif_stop_subqueue() vs netif_start_subqueue()
+	 */
+	__netif_tx_lock_bh(txq);
+
+	/* Prevent rx poll from accessing sq. */
+	sq->reset = true;
+
+	/* Prevent the upper layer from trying to send packets. */
+	netif_stop_subqueue(vi->dev, qindex);
+
+	__netif_tx_unlock_bh(txq);
+
+	err = virtqueue_resize(sq->vq, ring_num, virtnet_sq_free_unused_buf);
+	if (err)
+		netdev_err(vi->dev, "resize tx fail: tx queue index: %d err: %d\n", qindex, err);
+
+	__netif_tx_lock_bh(txq);
+	sq->reset = false;
+	netif_tx_wake_queue(txq);
+	__netif_tx_unlock_bh(txq);
+
+	if (running)
+		virtnet_napi_tx_enable(vi, sq->vq, &sq->napi);
+	return err;
 }
 
 /*
···
 {
 	struct virtnet_info *vi = netdev_priv(dev);
 
-	ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
-	ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
-	ring->rx_pending = ring->rx_max_pending;
-	ring->tx_pending = ring->tx_max_pending;
+	ring->rx_max_pending = vi->rq[0].vq->num_max;
+	ring->tx_max_pending = vi->sq[0].vq->num_max;
+	ring->rx_pending = virtqueue_get_vring_size(vi->rq[0].vq);
+	ring->tx_pending = virtqueue_get_vring_size(vi->sq[0].vq);
+}
+
+static int virtnet_set_ringparam(struct net_device *dev,
+				 struct ethtool_ringparam *ring,
+				 struct kernel_ethtool_ringparam *kernel_ring,
+				 struct netlink_ext_ack *extack)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	u32 rx_pending, tx_pending;
+	struct receive_queue *rq;
+	struct send_queue *sq;
+	int i, err;
+
+	if (ring->rx_mini_pending || ring->rx_jumbo_pending)
+		return -EINVAL;
+
+	rx_pending = virtqueue_get_vring_size(vi->rq[0].vq);
+	tx_pending = virtqueue_get_vring_size(vi->sq[0].vq);
+
+	if (ring->rx_pending == rx_pending &&
+	    ring->tx_pending == tx_pending)
+		return 0;
+
+	if (ring->rx_pending > vi->rq[0].vq->num_max)
+		return -EINVAL;
+
+	if (ring->tx_pending > vi->sq[0].vq->num_max)
+		return -EINVAL;
+
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		rq = vi->rq + i;
+		sq = vi->sq + i;
+
+		if (ring->tx_pending != tx_pending) {
+			err = virtnet_tx_resize(vi, sq, ring->tx_pending);
+			if (err)
+				return err;
+		}
+
+		if (ring->rx_pending != rx_pending) {
+			err = virtnet_rx_resize(vi, rq, ring->rx_pending);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
 }
 
 static bool virtnet_commit_rss_command(struct virtnet_info *vi)
···
 	return 0;
 }
 
+static int virtnet_send_notf_coal_cmds(struct virtnet_info *vi,
+				       struct ethtool_coalesce *ec)
+{
+	struct scatterlist sgs_tx, sgs_rx;
+	struct virtio_net_ctrl_coal_tx coal_tx;
+	struct virtio_net_ctrl_coal_rx coal_rx;
+
+	coal_tx.tx_usecs = cpu_to_le32(ec->tx_coalesce_usecs);
+	coal_tx.tx_max_packets = cpu_to_le32(ec->tx_max_coalesced_frames);
+	sg_init_one(&sgs_tx, &coal_tx, sizeof(coal_tx));
+
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL,
+				  VIRTIO_NET_CTRL_NOTF_COAL_TX_SET,
+				  &sgs_tx))
+		return -EINVAL;
+
+	/* Save parameters */
+	vi->tx_usecs = ec->tx_coalesce_usecs;
+	vi->tx_max_packets = ec->tx_max_coalesced_frames;
+
+	coal_rx.rx_usecs = cpu_to_le32(ec->rx_coalesce_usecs);
+	coal_rx.rx_max_packets = cpu_to_le32(ec->rx_max_coalesced_frames);
+	sg_init_one(&sgs_rx, &coal_rx, sizeof(coal_rx));
+
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL,
+				  VIRTIO_NET_CTRL_NOTF_COAL_RX_SET,
+				  &sgs_rx))
+		return -EINVAL;
+
+	/* Save parameters */
+	vi->rx_usecs = ec->rx_coalesce_usecs;
+	vi->rx_max_packets = ec->rx_max_coalesced_frames;
+
+	return 0;
+}
+
+static int virtnet_coal_params_supported(struct ethtool_coalesce *ec)
+{
+	/* usecs coalescing is supported only if VIRTIO_NET_F_NOTF_COAL
+	 * feature is negotiated.
+	 */
+	if (ec->rx_coalesce_usecs || ec->tx_coalesce_usecs)
+		return -EOPNOTSUPP;
+
+	if (ec->tx_max_coalesced_frames > 1 ||
+	    ec->rx_max_coalesced_frames != 1)
+		return -EINVAL;
+
+	return 0;
+}
+
 static int virtnet_set_coalesce(struct net_device *dev,
 				struct ethtool_coalesce *ec,
 				struct kernel_ethtool_coalesce *kernel_coal,
 				struct netlink_ext_ack *extack)
 {
 	struct virtnet_info *vi = netdev_priv(dev);
-	int i, napi_weight;
+	int ret, i, napi_weight;
+	bool update_napi = false;
 
-	if (ec->tx_max_coalesced_frames > 1 ||
-	    ec->rx_max_coalesced_frames != 1)
-		return -EINVAL;
-
+	/* Can't change NAPI weight if the link is up */
 	napi_weight = ec->tx_max_coalesced_frames ? NAPI_POLL_WEIGHT : 0;
 	if (napi_weight ^ vi->sq[0].napi.weight) {
 		if (dev->flags & IFF_UP)
 			return -EBUSY;
+		else
+			update_napi = true;
+	}
+
+	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL))
+		ret = virtnet_send_notf_coal_cmds(vi, ec);
+	else
+		ret = virtnet_coal_params_supported(ec);
+
+	if (ret)
+		return ret;
+
+	if (update_napi) {
 		for (i = 0; i < vi->max_queue_pairs; i++)
 			vi->sq[i].napi.weight = napi_weight;
 	}
 
-	return 0;
+	return ret;
 }
 
 static int virtnet_get_coalesce(struct net_device *dev,
···
 				struct kernel_ethtool_coalesce *kernel_coal,
 				struct netlink_ext_ack *extack)
 {
-	struct ethtool_coalesce ec_default = {
-		.cmd = ETHTOOL_GCOALESCE,
-		.rx_max_coalesced_frames = 1,
-	};
 	struct virtnet_info *vi = netdev_priv(dev);
 
-	memcpy(ec, &ec_default, sizeof(ec_default));
+	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) {
+		ec->rx_coalesce_usecs = vi->rx_usecs;
+		ec->tx_coalesce_usecs = vi->tx_usecs;
+		ec->tx_max_coalesced_frames = vi->tx_max_packets;
+		ec->rx_max_coalesced_frames = vi->rx_max_packets;
+	} else {
+		ec->rx_max_coalesced_frames = 1;
 
-	if (vi->sq[0].napi.weight)
-		ec->tx_max_coalesced_frames = 1;
+		if (vi->sq[0].napi.weight)
+			ec->tx_max_coalesced_frames = 1;
+	}
 
 	return 0;
 }
···
 }
 
 static const struct ethtool_ops virtnet_ethtool_ops = {
-	.supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES,
+	.supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES |
+		ETHTOOL_COALESCE_USECS,
 	.get_drvinfo = virtnet_get_drvinfo,
 	.get_link = ethtool_op_get_link,
 	.get_ringparam = virtnet_get_ringparam,
+	.set_ringparam = virtnet_set_ringparam,
 	.get_strings = virtnet_get_strings,
 	.get_sset_count = virtnet_get_sset_count,
 	.get_ethtool_stats = virtnet_get_ethtool_stats,
···
 			put_page(vi->rq[i].alloc_frag.page);
 }
 
+static void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf)
+{
+	if (!is_xdp_frame(buf))
+		dev_kfree_skb(buf);
+	else
+		xdp_return_frame(ptr_to_xdp(buf));
+}
+
+static void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf)
+{
+	struct virtnet_info *vi = vq->vdev->priv;
+	int i = vq2rxq(vq);
+
+	if (vi->mergeable_rx_bufs)
+		put_page(virt_to_head_page(buf));
+	else if (vi->big_packets)
+		give_pages(&vi->rq[i], buf);
+	else
+		put_page(virt_to_head_page(buf));
+}
+
 static void free_unused_bufs(struct virtnet_info *vi)
 {
 	void *buf;
···
 
 	for (i = 0; i < vi->max_queue_pairs; i++) {
 		struct virtqueue *vq = vi->sq[i].vq;
-		while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
-			if (!is_xdp_frame(buf))
-				dev_kfree_skb(buf);
-			else
-				xdp_return_frame(ptr_to_xdp(buf));
-		}
+		while ((buf = virtqueue_detach_unused_buf(vq)) != NULL)
+			virtnet_sq_free_unused_buf(vq, buf);
 	}
 
 	for (i = 0; i < vi->max_queue_pairs; i++) {
 		struct virtqueue *vq = vi->rq[i].vq;
-
-		while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
-			if (vi->mergeable_rx_bufs) {
-				put_page(virt_to_head_page(buf));
-			} else if (vi->big_packets) {
-				give_pages(&vi->rq[i], buf);
-			} else {
-				put_page(virt_to_head_page(buf));
-			}
-		}
+		while ((buf = virtqueue_detach_unused_buf(vq)) != NULL)
+			virtnet_rq_free_unused_buf(vq, buf);
 	}
 }
 
···
 		   (unsigned int)GOOD_PACKET_LEN);
 }
 
+static void virtnet_config_sizes(struct virtnet_info *vi, u32 *sizes)
+{
+	u32 i, rx_size, tx_size;
+
+	if (vi->speed == SPEED_UNKNOWN || vi->speed < SPEED_10000) {
+		rx_size = 1024;
+		tx_size = 1024;
+
+	} else if (vi->speed < SPEED_40000) {
+		rx_size = 1024 * 4;
+		tx_size = 1024 * 4;
+
+	} else {
+		rx_size = 1024 * 8;
+		tx_size = 1024 * 8;
+	}
+
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		sizes[rxq2vq(i)] = rx_size;
+		sizes[txq2vq(i)] = tx_size;
+	}
+}
+
 static int virtnet_find_vqs(struct virtnet_info *vi)
 {
 	vq_callback_t **callbacks;
···
 	int ret = -ENOMEM;
 	int i, total_vqs;
 	const char **names;
+	u32 *sizes;
 	bool *ctx;
 
 	/* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
···
 		ctx = NULL;
 	}
 
+	sizes = kmalloc_array(total_vqs, sizeof(*sizes), GFP_KERNEL);
+	if (!sizes)
+		goto err_sizes;
+
 	/* Parameters for control virtqueue, if any */
 	if (vi->has_cvq) {
 		callbacks[total_vqs - 1] = NULL;
 		names[total_vqs - 1] = "control";
+		sizes[total_vqs - 1] = 64;
 	}
 
 	/* Allocate/initialize parameters for send/receive virtqueues */
···
 			ctx[rxq2vq(i)] = true;
 	}
 
-	ret = virtio_find_vqs_ctx(vi->vdev, total_vqs, vqs, callbacks,
-				  names, ctx, NULL);
+	virtnet_config_sizes(vi, sizes);
+
+	ret = virtio_find_vqs_ctx_size(vi->vdev, total_vqs, vqs, callbacks,
+				       names, sizes, ctx, NULL);
 	if (ret)
 		goto err_find;
 
···
 
 
 err_find:
+	kfree(sizes);
+err_sizes:
 	kfree(ctx);
 err_ctx:
 	kfree(names);
···
 	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_RSS,
 			     "VIRTIO_NET_F_CTRL_VQ") ||
 	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_HASH_REPORT,
+			     "VIRTIO_NET_F_CTRL_VQ") ||
+	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_NOTF_COAL,
 			     "VIRTIO_NET_F_CTRL_VQ"))) {
 		return false;
 	}
···
 	if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
 		vi->mergeable_rx_bufs = true;
 
+	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) {
+		vi->rx_usecs = 0;
+		vi->tx_usecs = 0;
+		vi->tx_max_packets = 0;
+		vi->rx_max_packets = 0;
+	}
+
 	if (virtio_has_feature(vdev, VIRTIO_NET_F_HASH_REPORT))
 		vi->has_rss_hash_report = true;
 
···
 		vi->curr_queue_pairs = num_online_cpus();
 	vi->max_queue_pairs = max_queue_pairs;
 
+	virtnet_init_settings(dev);
+	virtnet_update_settings(vi);
+
 	/* Allocate/initialize the rx/tx queues, and invoke find_vqs */
 	err = init_vqs(vi);
 	if (err)
···
 #endif
 	netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
 	netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
-
-	virtnet_init_settings(dev);
 
 	if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY)) {
 		vi->failover = net_failover_create(vi->dev);
···
 	VIRTIO_NET_F_CTRL_MAC_ADDR, \
 	VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \
 	VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \
-	VIRTIO_NET_F_RSS, VIRTIO_NET_F_HASH_REPORT
+	VIRTIO_NET_F_RSS, VIRTIO_NET_F_HASH_REPORT, VIRTIO_NET_F_NOTF_COAL
 
 static unsigned int features[] = {
 	VIRTNET_FEATURES,

drivers/nvdimm/virtio_pmem.c

···
 	ndr_desc.res = &res;
 	ndr_desc.numa_node = nid;
 	ndr_desc.flush = async_pmem_flush;
+	ndr_desc.provider_data = vdev;
 	set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags);
 	set_bit(ND_REGION_ASYNC, &ndr_desc.flags);
+	/*
+	 * The NVDIMM region could be available before the
+	 * virtio_device_ready() that is called by
+	 * virtio_dev_probe(), so we set device ready here.
+	 */
+	virtio_device_ready(vdev);
 	nd_region = nvdimm_pmem_region_create(vpmem->nvdimm_bus, &ndr_desc);
 	if (!nd_region) {
 		dev_err(&vdev->dev, "failed to create nvdimm region\n");
 		err = -ENXIO;
 		goto out_nd;
 	}
-	nd_region->provider_data = dev_to_virtio(nd_region->dev.parent->parent);
 	return 0;
 out_nd:
+	virtio_reset_device(vdev);
 	nvdimm_bus_unregister(vpmem->nvdimm_bus);
 out_vq:
 	vdev->config->del_vqs(vdev);

drivers/platform/mellanox/mlxbf-tmfifo.c

···
 					struct virtqueue *vqs[],
 					vq_callback_t *callbacks[],
 					const char * const names[],
+					u32 sizes[],
 					const bool *ctx,
 					struct irq_affinity *desc)
 {
···
 			ret = -ENOMEM;
 			goto error;
 		}
+
+		vq->num_max = vring->num;
 
 		vqs[i] = vq;
 		vring->vq = vq;

drivers/remoteproc/remoteproc_core.c

···
 	size_t size;
 
 	/* actual size of vring (in bytes) */
-	size = PAGE_ALIGN(vring_size(rvring->len, rvring->align));
+	size = PAGE_ALIGN(vring_size(rvring->num, rvring->align));
 
 	rsc = (void *)rproc->table_ptr + rvdev->rsc_offset;
 
···
 		return -EINVAL;
 	}
 
-	rvring->len = vring->num;
+	rvring->num = vring->num;
 	rvring->align = vring->align;
 	rvring->rvdev = rvdev;
 

drivers/remoteproc/remoteproc_virtio.c

···
 	struct fw_rsc_vdev *rsc;
 	struct virtqueue *vq;
 	void *addr;
-	int len, size;
+	int num, size;
 
 	/* we're temporarily limited to two virtqueues per rvdev */
 	if (id >= ARRAY_SIZE(rvdev->vring))
···
 
 	rvring = &rvdev->vring[id];
 	addr = mem->va;
-	len = rvring->len;
+	num = rvring->num;
 
 	/* zero vring */
-	size = vring_size(len, rvring->align);
+	size = vring_size(num, rvring->align);
 	memset(addr, 0, size);
 
 	dev_dbg(dev, "vring%d: va %pK qsz %d notifyid %d\n",
-		id, addr, len, rvring->notifyid);
+		id, addr, num, rvring->notifyid);
 
 	/*
 	 * Create the new vq, and tell virtio we're not interested in
 	 * the 'weak' smp barriers, since we're talking with a real device.
 	 */
-	vq = vring_new_virtqueue(id, len, rvring->align, vdev, false, ctx,
+	vq = vring_new_virtqueue(id, num, rvring->align, vdev, false, ctx,
 				 addr, rproc_virtio_notify, callback, name);
 	if (!vq) {
 		dev_err(dev, "vring_new_virtqueue %s failed\n", name);
 		rproc_free_vring(rvring);
 		return ERR_PTR(-ENOMEM);
 	}
+
+	vq->num_max = num;
 
 	rvring->vq = vq;
 	vq->priv = rvring;
···
 				 struct virtqueue *vqs[],
 				 vq_callback_t *callbacks[],
 				 const char * const names[],
+				 u32 sizes[],
 				 const bool * ctx,
 				 struct irq_affinity *desc)
 {

drivers/s390/virtio/virtio_ccw.c

···
 		err = -ENOMEM;
 		goto out_err;
 	}
+
+	vq->num_max = info->num;
+
 	/* it may have been reduced */
 	info->num = virtqueue_get_vring_size(vq);
 
···
 			       struct virtqueue *vqs[],
 			       vq_callback_t *callbacks[],
 			       const char * const names[],
+			       u32 sizes[],
 			       const bool *ctx,
 			       struct irq_affinity *desc)
 {

drivers/vdpa/ifcvf/ifcvf_base.c

···
 {
 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
 
-	cfg = hw->common_cfg;
 	vp_iowrite16(vector,  &cfg->msix_config);
 
 	return vp_ioread16(&cfg->msix_config);
···
 			break;
 		case VIRTIO_PCI_CAP_DEVICE_CFG:
 			hw->dev_cfg = get_cap_addr(hw, &cap);
+			hw->cap_dev_config_size = le32_to_cpu(cap.length);
 			IFCVF_DBG(pdev, "hw->dev_cfg = %p\n", hw->dev_cfg);
 			break;
 		}
···
 u32 ifcvf_get_config_size(struct ifcvf_hw *hw)
 {
 	struct ifcvf_adapter *adapter;
+	u32 net_config_size = sizeof(struct virtio_net_config);
+	u32 blk_config_size = sizeof(struct virtio_blk_config);
+	u32 cap_size = hw->cap_dev_config_size;
 	u32 config_size;
 
 	adapter = vf_to_adapter(hw);
+	/* If the onboard device config space size is greater than
+	 * the size of struct virtio_net/blk_config, only the spec
+	 * implementing contents size is returned, this is very
+	 * unlikely, defensive programming.
+	 */
 	switch (hw->dev_type) {
 	case VIRTIO_ID_NET:
-		config_size = sizeof(struct virtio_net_config);
+		config_size = min(cap_size, net_config_size);
 		break;
 	case VIRTIO_ID_BLOCK:
-		config_size = sizeof(struct virtio_blk_config);
+		config_size = min(cap_size, blk_config_size);
 		break;
 	default:
 		config_size = 0;

drivers/vdpa/ifcvf/ifcvf_base.h

···
 	int config_irq;
 	int vqs_reused_irq;
 	u16 nr_vring;
+	/* VIRTIO_PCI_CAP_DEVICE_CFG size */
+	u32 cap_dev_config_size;
 };
 
 struct ifcvf_adapter {

drivers/vdpa/ifcvf/ifcvf_main.c

···
 }
 
 /*
- * IFCVF currently does't have on-chip IOMMU, so not
+ * IFCVF currently doesn't have on-chip IOMMU, so not
  * implemented set_map()/dma_map()/dma_unmap()
  */
 static const struct vdpa_config_ops ifc_vdpa_ops = {
···
 {
 	struct ifcvf_vdpa_mgmt_dev *ifcvf_mgmt_dev;
 	struct ifcvf_adapter *adapter;
+	struct vdpa_device *vdpa_dev;
 	struct pci_dev *pdev;
 	struct ifcvf_hw *vf;
-	struct device *dev;
-	int ret, i;
+	int ret;
 
 	ifcvf_mgmt_dev = container_of(mdev, struct ifcvf_vdpa_mgmt_dev, mdev);
-	if (ifcvf_mgmt_dev->adapter)
+	if (!ifcvf_mgmt_dev->adapter)
 		return -EOPNOTSUPP;
 
-	pdev = ifcvf_mgmt_dev->pdev;
-	dev = &pdev->dev;
-	adapter = vdpa_alloc_device(struct ifcvf_adapter, vdpa,
-				    dev, &ifc_vdpa_ops, 1, 1, name, false);
-	if (IS_ERR(adapter)) {
-		IFCVF_ERR(pdev, "Failed to allocate vDPA structure");
-		return PTR_ERR(adapter);
-	}
-
-	ifcvf_mgmt_dev->adapter = adapter;
-
+	adapter = ifcvf_mgmt_dev->adapter;
 	vf = &adapter->vf;
-	vf->dev_type = get_dev_type(pdev);
-	vf->base = pcim_iomap_table(pdev);
+	pdev = adapter->pdev;
+	vdpa_dev = &adapter->vdpa;
 
-	adapter->pdev = pdev;
-	adapter->vdpa.dma_dev = &pdev->dev;
+	if (name)
+		ret = dev_set_name(&vdpa_dev->dev, "%s", name);
+	else
+		ret = dev_set_name(&vdpa_dev->dev, "vdpa%u", vdpa_dev->index);
 
-	ret = ifcvf_init_hw(vf, pdev);
-	if (ret) {
-		IFCVF_ERR(pdev, "Failed to init IFCVF hw\n");
-		goto err;
-	}
-
-	for (i = 0; i < vf->nr_vring; i++)
-		vf->vring[i].irq = -EINVAL;
-
-	vf->hw_features = ifcvf_get_hw_features(vf);
-	vf->config_size = ifcvf_get_config_size(vf);
-
-	adapter->vdpa.mdev = &ifcvf_mgmt_dev->mdev;
 	ret = _vdpa_register_device(&adapter->vdpa, vf->nr_vring);
 	if (ret) {
+		put_device(&adapter->vdpa.dev);
 		IFCVF_ERR(pdev, "Failed to register to vDPA bus");
-		goto err;
+		return ret;
 	}
 
 	return 0;
-
-err:
-	put_device(&adapter->vdpa.dev);
-	return ret;
 }
+
 
 static void ifcvf_vdpa_dev_del(struct vdpa_mgmt_dev *mdev, struct vdpa_device *dev)
 {
···
 {
 	struct ifcvf_vdpa_mgmt_dev *ifcvf_mgmt_dev;
 	struct device *dev = &pdev->dev;
+	struct ifcvf_adapter *adapter;
+	struct ifcvf_hw *vf;
 	u32 dev_type;
-	int ret;
+	int ret, i;
+
+	ret = pcim_enable_device(pdev);
+	if (ret) {
+		IFCVF_ERR(pdev, "Failed to enable device\n");
+		return ret;
+	}
+	ret = pcim_iomap_regions(pdev, BIT(0) | BIT(2) | BIT(4),
+				 IFCVF_DRIVER_NAME);
+	if (ret) {
+		IFCVF_ERR(pdev, "Failed to request MMIO region\n");
+		return ret;
+	}
+
+	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
+	if (ret) {
+		IFCVF_ERR(pdev, "No usable DMA configuration\n");
+		return ret;
+	}
+
+	ret = devm_add_action_or_reset(dev, ifcvf_free_irq_vectors, pdev);
+	if (ret) {
+		IFCVF_ERR(pdev,
+			  "Failed for adding devres for freeing irq vectors\n");
+		return ret;
+	}
+
+	pci_set_master(pdev);
+
+	adapter = vdpa_alloc_device(struct ifcvf_adapter, vdpa,
+				    dev, &ifc_vdpa_ops, 1, 1, NULL, false);
+	if (IS_ERR(adapter)) {
+		IFCVF_ERR(pdev, "Failed to allocate vDPA structure");
+		return PTR_ERR(adapter);
+	}
+
+	vf = &adapter->vf;
+	vf->dev_type = get_dev_type(pdev);
+	vf->base = pcim_iomap_table(pdev);
+
+	adapter->pdev = pdev;
+	adapter->vdpa.dma_dev = &pdev->dev;
+
+	ret = ifcvf_init_hw(vf, pdev);
+	if (ret) {
+		IFCVF_ERR(pdev, "Failed to init IFCVF hw\n");
+		return ret;
+	}
+
+	for (i = 0; i < vf->nr_vring; i++)
+		vf->vring[i].irq = -EINVAL;
+
+	vf->hw_features = ifcvf_get_hw_features(vf);
+	vf->config_size = ifcvf_get_config_size(vf);
 
 	ifcvf_mgmt_dev = kzalloc(sizeof(struct ifcvf_vdpa_mgmt_dev), GFP_KERNEL);
 	if (!ifcvf_mgmt_dev) {
 		IFCVF_ERR(pdev, "Failed to alloc memory for the vDPA management device\n");
 		return -ENOMEM;
 	}
+
+	ifcvf_mgmt_dev->mdev.ops = &ifcvf_vdpa_mgmt_dev_ops;
+	ifcvf_mgmt_dev->mdev.device = dev;
+	ifcvf_mgmt_dev->adapter = adapter;
 
 	dev_type = get_dev_type(pdev);
 	switch (dev_type) {
···
 		goto err;
 	}
 
-	ifcvf_mgmt_dev->mdev.ops = &ifcvf_vdpa_mgmt_dev_ops;
-	ifcvf_mgmt_dev->mdev.device = dev;
-	ifcvf_mgmt_dev->pdev = pdev;
+	ifcvf_mgmt_dev->mdev.max_supported_vqs = vf->nr_vring;
+	ifcvf_mgmt_dev->mdev.supported_features = vf->hw_features;
 
-	ret = pcim_enable_device(pdev);
-	if (ret) {
-		IFCVF_ERR(pdev, "Failed to enable device\n");
-		goto err;
-	}
+	adapter->vdpa.mdev = &ifcvf_mgmt_dev->mdev;
 
-	ret = pcim_iomap_regions(pdev, BIT(0) | BIT(2) | BIT(4),
-				 IFCVF_DRIVER_NAME);
-	if (ret) {
-		IFCVF_ERR(pdev, "Failed to request MMIO region\n");
-		goto err;
-	}
-
-	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
-	if (ret) {
-		IFCVF_ERR(pdev, "No usable DMA configuration\n");
-		goto err;
-	}
-
-	ret = devm_add_action_or_reset(dev, ifcvf_free_irq_vectors, pdev);
-	if (ret) {
-		IFCVF_ERR(pdev,
-			  "Failed for adding devres for freeing irq vectors\n");
-		goto err;
-	}
-
-	pci_set_master(pdev);
 
 	ret = vdpa_mgmtdev_register(&ifcvf_mgmt_dev->mdev);
 	if (ret) {

drivers/vdpa/mlx5/core/mlx5_vdpa.h

···
 	struct mlx5_vdpa_dev *mvdev;
 };
 
+enum {
+	MLX5_VDPA_DATAVQ_GROUP,
+	MLX5_VDPA_CVQ_GROUP,
+	MLX5_VDPA_NUMVQ_GROUPS
+};
+
+enum {
+	MLX5_VDPA_NUM_AS = MLX5_VDPA_NUMVQ_GROUPS
+};
+
 struct mlx5_vdpa_dev {
 	struct vdpa_device vdev;
 	struct mlx5_core_dev *mdev;
···
 	struct mlx5_vdpa_mr mr;
 	struct mlx5_control_vq cvq;
 	struct workqueue_struct *wq;
+	unsigned int group2asid[MLX5_VDPA_NUMVQ_GROUPS];
 };
 
 int mlx5_vdpa_alloc_pd(struct mlx5_vdpa_dev *dev, u32 *pdn, u16 uid);

drivers/vdpa/mlx5/net/mlx5_vnet.c

···
 	bool setup;
 	u32 cur_num_vqs;
 	u32 rqt_size;
+	bool nb_registered;
 	struct notifier_block nb;
 	struct vdpa_callback config_cb;
 	struct mlx5_vdpa_wq_ent cvq_ent;
···
 	if (err)
 		goto err_cmd;
 
+	mvq->fw_state = MLX5_VIRTIO_NET_Q_OBJECT_STATE_INIT;
 	kfree(in);
 	mvq->virtq_id = MLX5_GET(general_obj_out_cmd_hdr, out, obj_id);
 
···
 		mlx5_vdpa_warn(&ndev->mvdev, "destroy virtqueue 0x%x\n", mvq->virtq_id);
 		return;
 	}
+	mvq->fw_state = MLX5_VIRTIO_NET_Q_OBJECT_NONE;
 	umems_destroy(ndev, mvq);
 }
 
···
 	return err;
 }
 
+static bool is_valid_state_change(int oldstate, int newstate)
+{
+	switch (oldstate) {
+	case MLX5_VIRTIO_NET_Q_OBJECT_STATE_INIT:
+		return newstate == MLX5_VIRTIO_NET_Q_OBJECT_STATE_RDY;
+	case MLX5_VIRTIO_NET_Q_OBJECT_STATE_RDY:
+		return newstate == MLX5_VIRTIO_NET_Q_OBJECT_STATE_SUSPEND;
+	case MLX5_VIRTIO_NET_Q_OBJECT_STATE_SUSPEND:
+	case MLX5_VIRTIO_NET_Q_OBJECT_STATE_ERR:
+	default:
+		return false;
+	}
+}
+
 static int modify_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq, int state)
 {
 	int inlen = MLX5_ST_SZ_BYTES(modify_virtio_net_q_in);
···
 	void *cmd_hdr;
 	void *in;
 	int err;
+
+	if (mvq->fw_state == MLX5_VIRTIO_NET_Q_OBJECT_NONE)
+		return 0;
+
+	if (!is_valid_state_change(mvq->fw_state, state))
+		return -EINVAL;
 
 	in = kzalloc(inlen, GFP_KERNEL);
 	if (!in)
···
 	headers_v = MLX5_ADDR_OF(fte_match_param, spec->match_value, outer_headers);
 	dmac_c = MLX5_ADDR_OF(fte_match_param, headers_c, outer_headers.dmac_47_16);
 	dmac_v = MLX5_ADDR_OF(fte_match_param, headers_v, outer_headers.dmac_47_16);
-	memset(dmac_c, 0xff, ETH_ALEN);
+	eth_broadcast_addr(dmac_c);
 	ether_addr_copy(dmac_v, mac);
 	MLX5_SET(fte_match_set_lyr_2_4, headers_c, cvlan_tag, 1);
 	if (tagged) {
···
 	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 	struct mlx5_vdpa_virtqueue *mvq;
+	int err;
 
 	if (!mvdev->actual_features)
 		return;
···
 	}
 
 	mvq = &ndev->vqs[idx];
-	if (!ready)
+	if (!ready) {
 		suspend_vq(ndev, mvq);
+	} else {
+		err = modify_virtqueue(ndev, mvq, MLX5_VIRTIO_NET_Q_OBJECT_STATE_RDY);
+		if (err) {
+			mlx5_vdpa_warn(mvdev, "modify VQ %d to ready failed (%d)\n", idx, err);
+			ready = false;
+		}
+	}
+
 
 	mvq->ready = ready;
 }
···
 	return PAGE_SIZE;
 }
 
-static u32 mlx5_vdpa_get_vq_group(struct vdpa_device *vdpa, u16 idx)
+static u32 mlx5_vdpa_get_vq_group(struct vdpa_device *vdev, u16 idx)
 {
-	return 0;
+	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
+
+	if (is_ctrl_vq_idx(mvdev, idx))
+		return MLX5_VDPA_CVQ_GROUP;
+
+	return MLX5_VDPA_DATAVQ_GROUP;
 }
 
 enum { MLX5_VIRTIO_NET_F_GUEST_CSUM = 1 << 9,
···
 	up_write(&ndev->reslock);
 }
 
+static void init_group_to_asid_map(struct mlx5_vdpa_dev *mvdev)
+{
+	int i;
+
+	/* default mapping all groups are mapped to asid 0 */
+	for (i = 0; i < MLX5_VDPA_NUMVQ_GROUPS; i++)
+		mvdev->group2asid[i] = 0;
+}
+
 static int mlx5_vdpa_reset(struct vdpa_device *vdev)
 {
 	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
···
 	ndev->mvdev.cvq.completed_desc = 0;
 	memset(ndev->event_cbs, 0, sizeof(*ndev->event_cbs) * (mvdev->max_vqs + 1));
 	ndev->mvdev.actual_features = 0;
+	init_group_to_asid_map(mvdev);
 	++mvdev->generation;
+
 	if (MLX5_CAP_GEN(mvdev->mdev, umem_uid_0)) {
 		if (mlx5_vdpa_create_mr(mvdev, NULL))
 			mlx5_vdpa_warn(mvdev, "create MR failed\n");
···
 	return mvdev->generation;
 }
 
-static int mlx5_vdpa_set_map(struct vdpa_device *vdev, unsigned int asid,
-			     struct vhost_iotlb *iotlb)
+static int set_map_control(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
 {
-	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
-	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
+	u64 start = 0ULL, last = 0ULL - 1;
+	struct vhost_iotlb_map *map;
+	int err = 0;
+
+	spin_lock(&mvdev->cvq.iommu_lock);
+	vhost_iotlb_reset(mvdev->cvq.iotlb);
+
+	for (map = vhost_iotlb_itree_first(iotlb, start, last); map;
+	     map = vhost_iotlb_itree_next(map, start, last)) {
+		err = vhost_iotlb_add_range(mvdev->cvq.iotlb, map->start,
+					    map->last, map->addr, map->perm);
+		if (err)
+			goto out;
+	}
+
+out:
+	spin_unlock(&mvdev->cvq.iommu_lock);
+	return err;
+}
+
+static int set_map_data(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
+{
 	bool change_map;
 	int err;
-
-	down_write(&ndev->reslock);
 
 	err = mlx5_vdpa_handle_set_map(mvdev, iotlb, &change_map);
 	if (err) {
 		mlx5_vdpa_warn(mvdev, "set map failed(%d)\n", err);
-		goto err;
+		return err;
 	}
 
 	if (change_map)
 		err = mlx5_vdpa_change_map(mvdev, iotlb);
 
-err:
+	return err;
+}
+
+static int mlx5_vdpa_set_map(struct vdpa_device *vdev, unsigned int asid,
+			     struct vhost_iotlb *iotlb)
+{
+	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
+	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
+	int err = -EINVAL;
+
+	down_write(&ndev->reslock);
+	if (mvdev->group2asid[MLX5_VDPA_DATAVQ_GROUP] == asid) {
+		err = set_map_data(mvdev, iotlb);
+		if (err)
+			goto out;
+	}
+
+	if (mvdev->group2asid[MLX5_VDPA_CVQ_GROUP] == asid)
+		err = set_map_control(mvdev, iotlb);
+
+out:
 	up_write(&ndev->reslock);
 	return err;
 }
···
 	return err;
 }
 
+static void mlx5_vdpa_cvq_suspend(struct mlx5_vdpa_dev *mvdev)
+{
+	struct mlx5_control_vq *cvq;
+
+	if (!(mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ)))
+		return;
+
+	cvq = &mvdev->cvq;
+	cvq->ready = false;
+}
+
+static int mlx5_vdpa_suspend(struct vdpa_device *vdev)
+{
+	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
+	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
+	struct mlx5_vdpa_virtqueue *mvq;
+	int i;
+
+	down_write(&ndev->reslock);
+	mlx5_notifier_unregister(mvdev->mdev, &ndev->nb);
+	ndev->nb_registered = false;
+	flush_workqueue(ndev->mvdev.wq);
+	for (i = 0; i < ndev->cur_num_vqs; i++) {
+		mvq = &ndev->vqs[i];
+		suspend_vq(ndev, mvq);
+	}
+	mlx5_vdpa_cvq_suspend(mvdev);
+	up_write(&ndev->reslock);
+	return 0;
+}
+
+static int mlx5_set_group_asid(struct vdpa_device *vdev, u32 group,
+			       unsigned int asid)
+{
+	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
+
+	if (group >= MLX5_VDPA_NUMVQ_GROUPS)
+		return -EINVAL;
+
+	mvdev->group2asid[group] = asid;
+	return 0;
+}
+
 static const struct vdpa_config_ops mlx5_vdpa_ops = {
 	.set_vq_address = mlx5_vdpa_set_vq_address,
 	.set_vq_num = mlx5_vdpa_set_vq_num,
···
 	.set_config = mlx5_vdpa_set_config,
 	.get_generation = mlx5_vdpa_get_generation,
 	.set_map = mlx5_vdpa_set_map,
+	.set_group_asid = mlx5_set_group_asid,
 	.free = mlx5_vdpa_free,
+	.suspend = mlx5_vdpa_suspend,
 };
 
 static int query_mtu(struct mlx5_core_dev *mdev, u16 *mtu)
···
 		mvq->index = i;
 		mvq->ndev = ndev;
 		mvq->fwqp.fw = true;
+		mvq->fw_state = MLX5_VIRTIO_NET_Q_OBJECT_NONE;
 	}
 	for (; i < ndev->mvdev.max_vqs; i++) {
 		mvq = &ndev->vqs[i];
···
 		switch (eqe->sub_type) {
 		case MLX5_PORT_CHANGE_SUBTYPE_DOWN:
 		case MLX5_PORT_CHANGE_SUBTYPE_ACTIVE:
-			wqent = kzalloc(sizeof(*wqent), GFP_ATOMIC);
-			if (!wqent)
+			down_read(&ndev->reslock);
+			if (!ndev->nb_registered) {
+				up_read(&ndev->reslock);
 				return NOTIFY_DONE;
+			}
+			wqent = kzalloc(sizeof(*wqent), GFP_ATOMIC);
+			if (!wqent) {
+				up_read(&ndev->reslock);
+				return NOTIFY_DONE;
+			}
 
 			wqent->mvdev = &ndev->mvdev;
 			INIT_WORK(&wqent->work, update_carrier);
 			queue_work(ndev->mvdev.wq, &wqent->work);
+			up_read(&ndev->reslock);
 			ret = NOTIFY_OK;
 			break;
 		default:
···
 	}
 
 	ndev = vdpa_alloc_device(struct mlx5_vdpa_net, mvdev.vdev, mdev->device, &mlx5_vdpa_ops,
-				 1, 1, name, false);
+				 MLX5_VDPA_NUMVQ_GROUPS, MLX5_VDPA_NUM_AS, name, false);
 	if (IS_ERR(ndev))
 		return PTR_ERR(ndev);
 
···
 
 	ndev->nb.notifier_call = event_handler;
 	mlx5_notifier_register(mdev, &ndev->nb);
+	ndev->nb_registered = true;
 	mvdev->vdev.mdev = &mgtdev->mgtdev;
 	err = _vdpa_register_device(&mvdev->vdev, max_vqs + 1);
 	if (err)
···
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 	struct workqueue_struct *wq;
 
-	mlx5_notifier_unregister(mvdev->mdev, &ndev->nb);
+	if (ndev->nb_registered) {
+		mlx5_notifier_unregister(mvdev->mdev, &ndev->nb);
+		ndev->nb_registered = false;
+	}
 	wq = mvdev->wq;
 	mvdev->wq = NULL;
 	destroy_workqueue(wq);

drivers/vdpa/vdpa.c

···
 		    config.mac))
 		return -EMSGSIZE;
 
-	val_u16 = le16_to_cpu(config.status);
+	val_u16 = __virtio16_to_cpu(true, config.status);
 	if (nla_put_u16(msg, VDPA_ATTR_DEV_NET_STATUS, val_u16))
 		return -EMSGSIZE;
 
-	val_u16 = le16_to_cpu(config.mtu);
+	val_u16 = __virtio16_to_cpu(true, config.mtu);
 	if (nla_put_u16(msg, VDPA_ATTR_DEV_NET_CFG_MTU, val_u16))
 		return -EMSGSIZE;
 
···
 {
 	u32 device_id;
 	void *hdr;
-	u8 status;
 	int err;
 
 	down_read(&vdev->cf_lock);
-	status = vdev->config->get_status(vdev);
-	if (!(status & VIRTIO_CONFIG_S_FEATURES_OK)) {
-		NL_SET_ERR_MSG_MOD(extack, "Features negotiation not completed");
-		err = -EAGAIN;
-		goto out;
-	}
-
 	hdr = genlmsg_put(msg, portid, seq, &vdpa_nl_family, flags,
 			  VDPA_CMD_DEV_CONFIG_GET);
 	if (!hdr) {
···
 	}
 	vdpa_get_config_unlocked(vdev, 0, &config, sizeof(config));
 
-	max_vqp = le16_to_cpu(config.max_virtqueue_pairs);
+	max_vqp = __virtio16_to_cpu(true, config.max_virtqueue_pairs);
 	if (nla_put_u16(msg, VDPA_ATTR_DEV_NET_CFG_MAX_VQP, max_vqp))
 		return -EMSGSIZE;
 

drivers/vdpa/vdpa_sim/vdpa_sim.c

···
 static int max_iotlb_entries = 2048;
 module_param(max_iotlb_entries, int, 0444);
 MODULE_PARM_DESC(max_iotlb_entries,
-		 "Maximum number of iotlb entries. 0 means unlimited. (default: 2048)");
+		 "Maximum number of iotlb entries for each address space. 0 means unlimited. (default: 2048)");
 
 #define VDPASIM_QUEUE_ALIGN PAGE_SIZE
 #define VDPASIM_QUEUE_MAX 256
···
 	for (i = 0; i < vdpasim->dev_attr.nas; i++)
 		vhost_iotlb_reset(&vdpasim->iommu[i]);
 
+	vdpasim->running = true;
 	spin_unlock(&vdpasim->iommu_lock);
 
 	vdpasim->features = 0;
···
 		goto err_iommu;
 
 	for (i = 0; i < vdpasim->dev_attr.nas; i++)
-		vhost_iotlb_init(&vdpasim->iommu[i], 0, 0);
+		vhost_iotlb_init(&vdpasim->iommu[i], max_iotlb_entries, 0);
 
 	vdpasim->buffer = kvmalloc(dev_attr->buffer_size, GFP_KERNEL);
 	if (!vdpasim->buffer)
···
 	return 0;
 }
 
+static int vdpasim_suspend(struct vdpa_device *vdpa)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+
+	spin_lock(&vdpasim->lock);
+	vdpasim->running = false;
+	spin_unlock(&vdpasim->lock);
+
+	return 0;
+}
+
 static size_t vdpasim_get_config_size(struct vdpa_device *vdpa)
 {
 	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
···
 	.get_status             = vdpasim_get_status,
 	.set_status             = vdpasim_set_status,
 	.reset			= vdpasim_reset,
+	.suspend		= vdpasim_suspend,
 	.get_config_size        = vdpasim_get_config_size,
 	.get_config             = vdpasim_get_config,
 	.set_config             = vdpasim_set_config,
···
 	.get_status             = vdpasim_get_status,
 	.set_status             = vdpasim_set_status,
 	.reset			= vdpasim_reset,
+	.suspend		= vdpasim_suspend,
 	.get_config_size        = vdpasim_get_config_size,
 	.get_config             = vdpasim_get_config,
 	.set_config             = vdpasim_set_config,

drivers/vdpa/vdpa_sim/vdpa_sim.h

···
 	u32 generation;
 	u64 features;
 	u32 groups;
+	bool running;
 	/* spinlock to synchronize iommu table */
 	spinlock_t iommu_lock;
 };

drivers/vdpa/vdpa_sim/vdpa_sim_blk.c

···
 #define DRV_LICENSE  "GPL v2"
 
 #define VDPASIM_BLK_FEATURES	(VDPASIM_FEATURES | \
+				 (1ULL << VIRTIO_BLK_F_FLUSH)    | \
 				 (1ULL << VIRTIO_BLK_F_SIZE_MAX) | \
 				 (1ULL << VIRTIO_BLK_F_SEG_MAX)  | \
 				 (1ULL << VIRTIO_BLK_F_BLK_SIZE) | \
 				 (1ULL << VIRTIO_BLK_F_TOPOLOGY) | \
-				 (1ULL << VIRTIO_BLK_F_MQ))
+				 (1ULL << VIRTIO_BLK_F_MQ)       | \
+				 (1ULL << VIRTIO_BLK_F_DISCARD)  | \
+				 (1ULL << VIRTIO_BLK_F_WRITE_ZEROES))
 
 #define VDPASIM_BLK_CAPACITY	0x40000
 #define VDPASIM_BLK_SIZE_MAX	0x1000
 #define VDPASIM_BLK_SEG_MAX	32
+#define VDPASIM_BLK_DWZ_MAX_SECTORS UINT_MAX
+
+/* 1 virtqueue, 1 address space, 1 virtqueue group */
 #define VDPASIM_BLK_VQ_NUM	1
+#define VDPASIM_BLK_AS_NUM	1
+#define VDPASIM_BLK_GROUP_NUM	1
 
 static char vdpasim_blk_id[VIRTIO_BLK_ID_BYTES] = "vdpa_blk_sim";
 
-static bool vdpasim_blk_check_range(u64 start_sector, size_t range_size)
+static bool vdpasim_blk_check_range(struct vdpasim *vdpasim, u64 start_sector,
+				    u64 num_sectors, u64 max_sectors)
 {
-	u64 range_sectors = range_size >> SECTOR_SHIFT;
+	if (start_sector > VDPASIM_BLK_CAPACITY) {
+		dev_dbg(&vdpasim->vdpa.dev,
+			"starting sector exceeds the capacity - start: 0x%llx capacity: 0x%x\n",
+			start_sector, VDPASIM_BLK_CAPACITY);
+	}
 
-	if (range_size > VDPASIM_BLK_SIZE_MAX * VDPASIM_BLK_SEG_MAX)
+	if (num_sectors > max_sectors) {
+		dev_dbg(&vdpasim->vdpa.dev,
+			"number of sectors exceeds the max allowed in a request - num: 0x%llx max: 0x%llx\n",
+			num_sectors, max_sectors);
 		return false;
+	}
 
-	if (start_sector > VDPASIM_BLK_CAPACITY)
+	if (num_sectors > VDPASIM_BLK_CAPACITY - start_sector) {
+		dev_dbg(&vdpasim->vdpa.dev,
+			"request exceeds the capacity - start: 0x%llx num: 0x%llx capacity: 0x%x\n",
+			start_sector, num_sectors, VDPASIM_BLK_CAPACITY);
 		return false;
-
-	if (range_sectors > VDPASIM_BLK_CAPACITY - start_sector)
-		return false;
+	}
 
 	return true;
 }
···
 {
 	size_t pushed = 0, to_pull, to_push;
 	struct virtio_blk_outhdr hdr;
+	bool handled = false;
 	ssize_t bytes;
 	loff_t offset;
 	u64 sector;
···
 		return false;
 
 	if (vq->out_iov.used < 1 || vq->in_iov.used < 1) {
-		dev_err(&vdpasim->vdpa.dev, "missing headers - out_iov: %u in_iov %u\n",
+		dev_dbg(&vdpasim->vdpa.dev, "missing headers - out_iov: %u in_iov %u\n",
 			vq->out_iov.used, vq->in_iov.used);
-		return false;
+		goto err;
 	}
 
 	if (vq->in_iov.iov[vq->in_iov.used - 1].iov_len < 1) {
-		dev_err(&vdpasim->vdpa.dev, "request in header too short\n");
-		return false;
+		dev_dbg(&vdpasim->vdpa.dev, "request in header too short\n");
+		goto err;
 	}
 
 	/* The last byte is the status and we checked if the last iov has
···
 	bytes = vringh_iov_pull_iotlb(&vq->vring, &vq->out_iov, &hdr,
 				      sizeof(hdr));
 	if (bytes != sizeof(hdr)) {
-		dev_err(&vdpasim->vdpa.dev, "request out header too short\n");
-		return false;
+		dev_dbg(&vdpasim->vdpa.dev, "request out header too short\n");
+		goto err;
 	}
 
 	to_pull -= bytes;
···
 	offset = sector << SECTOR_SHIFT;
 	status = VIRTIO_BLK_S_OK;
 
+	if (type != VIRTIO_BLK_T_IN && type != VIRTIO_BLK_T_OUT &&
+	    sector != 0) {
+		dev_dbg(&vdpasim->vdpa.dev,
+			"sector must be 0 for %u request - sector: 0x%llx\n",
+			type, sector);
+		status = VIRTIO_BLK_S_IOERR;
+		goto err_status;
+	}
+
 	switch (type) {
 	case VIRTIO_BLK_T_IN:
-		if (!vdpasim_blk_check_range(sector, to_push)) {
-			dev_err(&vdpasim->vdpa.dev,
-				"reading over the capacity - offset: 0x%llx len: 0x%zx\n",
-				offset, to_push);
+		if (!vdpasim_blk_check_range(vdpasim, sector,
+					     to_push >> SECTOR_SHIFT,
+					     VDPASIM_BLK_SIZE_MAX * VDPASIM_BLK_SEG_MAX)) {
 			status = VIRTIO_BLK_S_IOERR;
 			break;
 		}
···
 					      vdpasim->buffer + offset,
 					      to_push);
 		if (bytes < 0) {
-			dev_err(&vdpasim->vdpa.dev,
+			dev_dbg(&vdpasim->vdpa.dev,
 				"vringh_iov_push_iotlb() error: %zd offset: 0x%llx len: 0x%zx\n",
 				bytes, offset, to_push);
 			status = VIRTIO_BLK_S_IOERR;
···
 		break;
 
 	case VIRTIO_BLK_T_OUT:
-		if (!vdpasim_blk_check_range(sector, to_pull)) {
-			dev_err(&vdpasim->vdpa.dev,
-				"writing over the capacity - offset: 0x%llx len: 0x%zx\n",
-				offset, to_pull);
+		if (!vdpasim_blk_check_range(vdpasim, sector,
+					     to_pull >> SECTOR_SHIFT,
+					     VDPASIM_BLK_SIZE_MAX * VDPASIM_BLK_SEG_MAX)) {
 			status = VIRTIO_BLK_S_IOERR;
 			break;
 		}
···
 					      vdpasim->buffer + offset,
 					      to_pull);
 		if (bytes < 0) {
-			dev_err(&vdpasim->vdpa.dev,
+			dev_dbg(&vdpasim->vdpa.dev,
 				"vringh_iov_pull_iotlb() error: %zd offset: 0x%llx len: 0x%zx\n",
 				bytes, offset, to_pull);
 			status = VIRTIO_BLK_S_IOERR;
···
 					      vdpasim_blk_id,
 					      VIRTIO_BLK_ID_BYTES);
 		if (bytes < 0) {
-			dev_err(&vdpasim->vdpa.dev,
+			dev_dbg(&vdpasim->vdpa.dev,
 				"vringh_iov_push_iotlb() error: %zd\n", bytes);
 			status = VIRTIO_BLK_S_IOERR;
 			break;
···
 		pushed += bytes;
 		break;
 
+	case VIRTIO_BLK_T_FLUSH:
+		/* nothing to do */
+		break;
+
+	case VIRTIO_BLK_T_DISCARD:
+	case VIRTIO_BLK_T_WRITE_ZEROES: {
+		struct virtio_blk_discard_write_zeroes range;
+		u32 num_sectors, flags;
+
+		if (to_pull != sizeof(range)) {
+			dev_dbg(&vdpasim->vdpa.dev,
+				"discard/write_zeroes header len: 0x%zx [expected: 0x%zx]\n",
+				to_pull, sizeof(range));
+			status = VIRTIO_BLK_S_IOERR;
+			break;
+		}
+
+		bytes = vringh_iov_pull_iotlb(&vq->vring, &vq->out_iov, &range,
+					      to_pull);
+		if (bytes < 0) {
+			dev_dbg(&vdpasim->vdpa.dev,
+				"vringh_iov_pull_iotlb() error: %zd offset: 0x%llx len: 0x%zx\n",
+				bytes, offset, to_pull);
+			status = VIRTIO_BLK_S_IOERR;
+			break;
+		}
+
+		sector = le64_to_cpu(range.sector);
+		offset = sector << SECTOR_SHIFT;
+		num_sectors = le32_to_cpu(range.num_sectors);
+		flags = le32_to_cpu(range.flags);
+
+		if (type == VIRTIO_BLK_T_DISCARD && flags != 0) {
+			dev_dbg(&vdpasim->vdpa.dev,
+				"discard unexpected flags set - flags: 0x%x\n",
+				flags);
+			status = VIRTIO_BLK_S_UNSUPP;
+			break;
+		}
+
+		if (type == VIRTIO_BLK_T_WRITE_ZEROES &&
+		    flags & ~VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP) {
+			dev_dbg(&vdpasim->vdpa.dev,
+				"write_zeroes unexpected flags set - flags: 0x%x\n",
+				flags);
+			status = VIRTIO_BLK_S_UNSUPP;
+			break;
+		}
+
+		if (!vdpasim_blk_check_range(vdpasim, sector, num_sectors,
+					     VDPASIM_BLK_DWZ_MAX_SECTORS)) {
+			status = VIRTIO_BLK_S_IOERR;
+			break;
+		}
+
+		if (type == VIRTIO_BLK_T_WRITE_ZEROES) {
+			memset(vdpasim->buffer + offset, 0,
+			       num_sectors << SECTOR_SHIFT);
+		}
+
+		break;
+	}
 	default:
-		dev_warn(&vdpasim->vdpa.dev,
-			 "Unsupported request type %d\n", type);
+		dev_dbg(&vdpasim->vdpa.dev,
+			"Unsupported request type %d\n", type);
 		status = VIRTIO_BLK_S_IOERR;
 		break;
 	}
 
+err_status:
 	/* If some operations fail, we need to skip the remaining bytes
 	 * to put the status in the last byte
 	 */
···
 	/* Last byte is the status */
 	bytes = vringh_iov_push_iotlb(&vq->vring, &vq->in_iov, &status, 1);
 	if (bytes != 1)
-		return false;
+		goto err;
 
 	pushed += bytes;
 
 	/* Make sure data is wrote before advancing index */
 	smp_wmb();
 
+	handled = true;
+
+err:
 	vringh_complete_iotlb(&vq->vring, vq->head, pushed);
 
-	return true;
+	return handled;
 }
 
 static void vdpasim_blk_work(struct work_struct *work)
 {
 	struct vdpasim *vdpasim = container_of(work, struct vdpasim, work);
+	bool reschedule = false;
 	int i;
 
 	spin_lock(&vdpasim->lock);
···
 	if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK))
 		goto out;
 
+	if (!vdpasim->running)
+		goto out;
+
 	for (i = 0; i < VDPASIM_BLK_VQ_NUM; i++) {
 		struct vdpasim_virtqueue *vq = &vdpasim->vqs[i];
+		int reqs = 0;
 
 		if (!vq->ready)
 			continue;
···
 			if (vringh_need_notify_iotlb(&vq->vring) > 0)
 				vringh_notify(&vq->vring);
 			local_bh_enable();
+
+			if (++reqs > 4) {
+				reschedule = true;
+				break;
+			}
 		}
 	}
 out:
 	spin_unlock(&vdpasim->lock);
+
+	if (reschedule)
+		schedule_work(&vdpasim->work);
 }
 
 static void vdpasim_blk_get_config(struct vdpasim *vdpasim, void *config)
···
 	blk_config->min_io_size = cpu_to_vdpasim16(vdpasim, 1);
 	blk_config->opt_io_size = cpu_to_vdpasim32(vdpasim, 1);
 	blk_config->blk_size = cpu_to_vdpasim32(vdpasim, SECTOR_SIZE);
+	/* VIRTIO_BLK_F_DISCARD */
+	blk_config->discard_sector_alignment =
+		cpu_to_vdpasim32(vdpasim, SECTOR_SIZE);
+	blk_config->max_discard_sectors =
+		cpu_to_vdpasim32(vdpasim, VDPASIM_BLK_DWZ_MAX_SECTORS);
+	blk_config->max_discard_seg = cpu_to_vdpasim32(vdpasim, 1);
+	/* VIRTIO_BLK_F_WRITE_ZEROES */
+	blk_config->max_write_zeroes_sectors =
+		cpu_to_vdpasim32(vdpasim, VDPASIM_BLK_DWZ_MAX_SECTORS);
+	blk_config->max_write_zeroes_seg = cpu_to_vdpasim32(vdpasim, 1);
+
 }
 
 static void vdpasim_blk_mgmtdev_release(struct device *dev)
···
 	dev_attr.id = VIRTIO_ID_BLOCK;
 	dev_attr.supported_features = VDPASIM_BLK_FEATURES;
 	dev_attr.nvqs = VDPASIM_BLK_VQ_NUM;
+	dev_attr.ngroups = VDPASIM_BLK_GROUP_NUM;
+	dev_attr.nas = VDPASIM_BLK_AS_NUM;
 	dev_attr.config_size = sizeof(struct virtio_blk_config);
 	dev_attr.get_config = vdpasim_blk_get_config;
 	dev_attr.work_fn = vdpasim_blk_work;

drivers/vdpa/vdpa_sim/vdpa_sim_net.c

···
 
 	spin_lock(&vdpasim->lock);
 
+	if (!vdpasim->running)
+		goto out;
+
 	if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK))
 		goto out;
 

drivers/vdpa/vdpa_user/iova_domain.c

···
 {
 	unsigned long pfn = PFN_DOWN(orig);
 	unsigned int offset = offset_in_page(orig);
-	char *buffer;
+	struct page *page;
 	unsigned int sz = 0;
 
 	while (size) {
 		sz = min_t(size_t, PAGE_SIZE - offset, size);
 
-		buffer = kmap_atomic(pfn_to_page(pfn));
+		page = pfn_to_page(pfn);
 		if (dir == DMA_TO_DEVICE)
-			memcpy(addr, buffer + offset, sz);
+			memcpy_from_page(addr, page, offset, sz);
 		else
-			memcpy(buffer + offset, addr, sz);
-		kunmap_atomic(buffer);
+			memcpy_to_page(page, offset, addr, sz);
 
 		size -= sz;
 		pfn++;
···
 			    map->orig_phys == INVALID_PHYS_ADDR))
 			return;
 
-		addr = page_address(map->bounce_page) + offset;
-		do_bounce(map->orig_phys + offset, addr, sz, dir);
+		addr = kmap_local_page(map->bounce_page);
+		do_bounce(map->orig_phys + offset, addr + offset, sz, dir);
+		kunmap_local(addr);
 		size -= sz;
 		iova += sz;
 	}
···
 	struct vduse_bounce_map *map;
 	struct page *page = NULL;
 
-	spin_lock(&domain->iotlb_lock);
+	read_lock(&domain->bounce_lock);
 	map = &domain->bounce_maps[iova >> PAGE_SHIFT];
-	if (!map->bounce_page)
+	if (domain->user_bounce_pages || !map->bounce_page)
 		goto out;
 
 	page = map->bounce_page;
 	get_page(page);
 out:
-	spin_unlock(&domain->iotlb_lock);
+	read_unlock(&domain->bounce_lock);
 
 	return page;
 }
 
 static void
-vduse_domain_free_bounce_pages(struct vduse_iova_domain *domain)
+vduse_domain_free_kernel_bounce_pages(struct vduse_iova_domain *domain)
 {
 	struct vduse_bounce_map *map;
 	unsigned long pfn, bounce_pfns;
···
 		__free_page(map->bounce_page);
 		map->bounce_page = NULL;
 	}
+}
+
+int vduse_domain_add_user_bounce_pages(struct vduse_iova_domain *domain,
+				       struct page **pages, int count)
+{
+	struct vduse_bounce_map *map;
+	int i, ret;
+
+	/* Now we don't support partial mapping */
+	if (count != (domain->bounce_size >> PAGE_SHIFT))
+		return -EINVAL;
+
+	write_lock(&domain->bounce_lock);
+	ret = -EEXIST;
+	if (domain->user_bounce_pages)
+		goto out;
+
+	for (i = 0; i < count; i++) {
+		map = &domain->bounce_maps[i];
+		if (map->bounce_page) {
+			/* Copy kernel page to user page if it's in use */
+			if (map->orig_phys != INVALID_PHYS_ADDR)
+				memcpy_to_page(pages[i], 0,
+					       page_address(map->bounce_page),
+					       PAGE_SIZE);
+			__free_page(map->bounce_page);
+		}
+		map->bounce_page = pages[i];
+		get_page(pages[i]);
+	}
+	domain->user_bounce_pages = true;
+	ret = 0;
+out:
+	write_unlock(&domain->bounce_lock);
+
+	return ret;
+}
+
+void vduse_domain_remove_user_bounce_pages(struct vduse_iova_domain *domain)
+{
+	struct vduse_bounce_map *map;
+	unsigned long i, count;
+
+	write_lock(&domain->bounce_lock);
+	if (!domain->user_bounce_pages)
+		goto out;
+
+	count = domain->bounce_size >> PAGE_SHIFT;
+	for (i = 0; i < count; i++) {
+		struct page *page = NULL;
+
+		map = &domain->bounce_maps[i];
+		if (WARN_ON(!map->bounce_page))
+			continue;
+
+		/* Copy user page to kernel page if it's in use */
+		if (map->orig_phys != INVALID_PHYS_ADDR) {
+			page = alloc_page(GFP_ATOMIC | __GFP_NOFAIL);
+			memcpy_from_page(page_address(page),
+					 map->bounce_page, 0, PAGE_SIZE);
+		}
+		put_page(map->bounce_page);
+		map->bounce_page = page;
+	}
+	domain->user_bounce_pages = false;
+out:
+	write_unlock(&domain->bounce_lock);
 }
 
 void vduse_domain_reset_bounce_map(struct vduse_iova_domain *domain)
···
 	if (vduse_domain_init_bounce_map(domain))
 		goto err;
 
+	read_lock(&domain->bounce_lock);
 	if (vduse_domain_map_bounce_page(domain, (u64)iova, (u64)size, pa))
-		goto err;
+		goto err_unlock;
 
 	if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
 		vduse_domain_bounce(domain, iova, size, DMA_TO_DEVICE);
 
+	read_unlock(&domain->bounce_lock);
+
 	return iova;
+err_unlock:
+	read_unlock(&domain->bounce_lock);
 err:
 	vduse_domain_free_iova(iovad, iova, size);
 	return DMA_MAPPING_ERROR;
···
 {
 	struct iova_domain *iovad = &domain->stream_iovad;
 
+	read_lock(&domain->bounce_lock);
 	if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
 		vduse_domain_bounce(domain, dma_addr, size, DMA_FROM_DEVICE);
 
 	vduse_domain_unmap_bounce_page(domain, (u64)dma_addr, (u64)size);
+	read_unlock(&domain->bounce_lock);
 	vduse_domain_free_iova(iovad, dma_addr, size);
 }
 
···
 
 	spin_lock(&domain->iotlb_lock);
 	vduse_iotlb_del_range(domain, 0, ULLONG_MAX);
-	vduse_domain_free_bounce_pages(domain);
+	vduse_domain_remove_user_bounce_pages(domain);
+	vduse_domain_free_kernel_bounce_pages(domain);
 	spin_unlock(&domain->iotlb_lock);
 	put_iova_domain(&domain->stream_iovad);
 	put_iova_domain(&domain->consistent_iovad);
···
 		goto err_file;
 
 	domain->file = file;
+	rwlock_init(&domain->bounce_lock);
 	spin_lock_init(&domain->iotlb_lock);
 	init_iova_domain(&domain->stream_iovad,
 			PAGE_SIZE, IOVA_START_PFN);

drivers/vdpa/vdpa_user/iova_domain.h

···
 #include <linux/iova.h>
 #include <linux/dma-mapping.h>
 #include <linux/vhost_iotlb.h>
+#include <linux/rwlock.h>
 
 #define IOVA_START_PFN 1
 
···
 	struct vhost_iotlb *iotlb;
 	spinlock_t iotlb_lock;
 	struct file *file;
+	bool user_bounce_pages;
+	rwlock_t bounce_lock;
 };
 
 int vduse_domain_set_map(struct vduse_iova_domain *domain,
···
 				unsigned long attrs);
 
 void vduse_domain_reset_bounce_map(struct vduse_iova_domain *domain);
+
+int vduse_domain_add_user_bounce_pages(struct vduse_iova_domain *domain,
+				       struct page **pages, int count);
+
+void vduse_domain_remove_user_bounce_pages(struct vduse_iova_domain *domain);
 
 void vduse_domain_destroy(struct vduse_iova_domain *domain);
 

drivers/vdpa/vdpa_user/vduse_dev.c

···
 #include <linux/uio.h>
 #include <linux/vdpa.h>
 #include <linux/nospec.h>
+#include <linux/vmalloc.h>
+#include <linux/sched/mm.h>
 #include <uapi/linux/vduse.h>
 #include <uapi/linux/vdpa.h>
 #include <uapi/linux/virtio_config.h>
···
 	struct vduse_dev *dev;
 };
 
+struct vduse_umem {
+	unsigned long iova;
+	unsigned long npages;
+	struct page **pages;
+	struct mm_struct *mm;
+};
+
 struct vduse_dev {
 	struct vduse_vdpa *vdev;
 	struct device *dev;
···
 	u8 status;
 	u32 vq_num;
 	u32 vq_align;
+	struct vduse_umem *umem;
+	struct mutex mem_lock;
 };
 
 struct vduse_dev_msg {
···
 	return ret;
 }
 
+static int vduse_dev_dereg_umem(struct vduse_dev *dev,
+				u64 iova, u64 size)
+{
+	int ret;
+
+	mutex_lock(&dev->mem_lock);
+	ret = -ENOENT;
+	if (!dev->umem)
+		goto unlock;
+
+	ret = -EINVAL;
+	if (dev->umem->iova != iova || size != dev->domain->bounce_size)
+		goto unlock;
+
+	vduse_domain_remove_user_bounce_pages(dev->domain);
+	unpin_user_pages_dirty_lock(dev->umem->pages,
+				    dev->umem->npages, true);
+	atomic64_sub(dev->umem->npages, &dev->umem->mm->pinned_vm);
+	mmdrop(dev->umem->mm);
+	vfree(dev->umem->pages);
+	kfree(dev->umem);
+	dev->umem = NULL;
+	ret = 0;
+unlock:
+	mutex_unlock(&dev->mem_lock);
+	return ret;
+}
+
+static int vduse_dev_reg_umem(struct vduse_dev *dev,
+			      u64 iova, u64 uaddr, u64 size)
+{
+	struct page **page_list = NULL;
+	struct vduse_umem *umem = NULL;
+	long pinned = 0;
+	unsigned long npages, lock_limit;
+	int ret;
+
+	if (!dev->domain->bounce_map ||
+	    size != dev->domain->bounce_size ||
+	    iova != 0 || uaddr & ~PAGE_MASK)
+		return -EINVAL;
+
+	mutex_lock(&dev->mem_lock);
+	ret = -EEXIST;
+	if (dev->umem)
+		goto unlock;
+
+	ret = -ENOMEM;
+	npages = size >> PAGE_SHIFT;
+	page_list = __vmalloc(array_size(npages, sizeof(struct page *)),
+			      GFP_KERNEL_ACCOUNT);
+	umem = kzalloc(sizeof(*umem), GFP_KERNEL);
+	if (!page_list || !umem)
+		goto unlock;
+
+	mmap_read_lock(current->mm);
+
+	lock_limit = PFN_DOWN(rlimit(RLIMIT_MEMLOCK));
+	if (npages + atomic64_read(&current->mm->pinned_vm) > lock_limit)
+		goto out;
+
+	pinned = pin_user_pages(uaddr, npages, FOLL_LONGTERM | FOLL_WRITE,
+				page_list, NULL);
+	if (pinned != npages) {
+		ret = pinned < 0 ? pinned : -ENOMEM;
+		goto out;
+	}
+
+	ret = vduse_domain_add_user_bounce_pages(dev->domain,
+						 page_list, pinned);
+	if (ret)
+		goto out;
+
+	atomic64_add(npages, &current->mm->pinned_vm);
+
+	umem->pages = page_list;
+	umem->npages = pinned;
+	umem->iova = iova;
+	umem->mm = current->mm;
+	mmgrab(current->mm);
+
+	dev->umem = umem;
+out:
+	if (ret && pinned > 0)
+		unpin_user_pages(page_list, pinned);
+
+	mmap_read_unlock(current->mm);
+unlock:
+	if (ret) {
+		vfree(page_list);
+		kfree(umem);
+	}
+	mutex_unlock(&dev->mem_lock);
+	return ret;
+}
+
 static long vduse_dev_ioctl(struct file *file, unsigned int cmd,
 			    unsigned long arg)
 {
···
 		ret = vduse_dev_queue_irq_work(dev, &dev->vqs[index].inject);
 		break;
 	}
+	case VDUSE_IOTLB_REG_UMEM: {
+		struct vduse_iova_umem umem;
+
+		ret = -EFAULT;
+		if (copy_from_user(&umem, argp, sizeof(umem)))
+			break;
+
+		ret = -EINVAL;
+		if (!is_mem_zero((const char *)umem.reserved,
+				 sizeof(umem.reserved)))
+			break;
+
+		ret = vduse_dev_reg_umem(dev, umem.iova,
+					 umem.uaddr, umem.size);
+		break;
+	}
+	case VDUSE_IOTLB_DEREG_UMEM: {
+		struct vduse_iova_umem umem;
+
+		ret = -EFAULT;
+		if (copy_from_user(&umem, argp, sizeof(umem)))
+			break;
+
+		ret = -EINVAL;
+		if (!is_mem_zero((const char *)umem.reserved,
+				 sizeof(umem.reserved)))
+			break;
+
+		ret = vduse_dev_dereg_umem(dev, umem.iova,
+					   umem.size);
+		break;
+	}
+	case VDUSE_IOTLB_GET_INFO: {
+		struct vduse_iova_info info;
+		struct vhost_iotlb_map *map;
+		struct vduse_iova_domain *domain = dev->domain;
+
+		ret = -EFAULT;
+		if (copy_from_user(&info, argp, sizeof(info)))
+			break;
+
+		ret = -EINVAL;
+		if (info.start > info.last)
+			break;
+
+		if (!is_mem_zero((const char *)info.reserved,
+				 sizeof(info.reserved)))
+			break;
+
+		spin_lock(&domain->iotlb_lock);
+		map = vhost_iotlb_itree_first(domain->iotlb,
+					      info.start, info.last);
+		if (map) {
+			info.start = map->start;
+			info.last = map->last;
+			info.capability = 0;
+			if (domain->bounce_map && map->start == 0 &&
+			    map->last == domain->bounce_size - 1)
+				info.capability |= VDUSE_IOVA_CAP_UMEM;
+		}
+		spin_unlock(&domain->iotlb_lock);
+		if (!map)
+			break;
+
+		ret = -EFAULT;
+		if (copy_to_user(argp, &info, sizeof(info)))
+			break;
+
+		ret = 0;
+		break;
+	}
 	default:
 		ret = -ENOIOCTLCMD;
 		break;
···
 {
 	struct vduse_dev *dev = file->private_data;
 
+	vduse_dev_dereg_umem(dev, 0, dev->domain->bounce_size);
 	spin_lock(&dev->msg_lock);
 	/* Make sure the inflight messages can processed after reconncection */
 	list_splice_init(&dev->recv_list, &dev->send_list);
···
 		return NULL;
 
 	mutex_init(&dev->lock);
+	mutex_init(&dev->mem_lock);
 	spin_lock_init(&dev->msg_lock);
 	INIT_LIST_HEAD(&dev->send_list);
 	INIT_LIST_HEAD(&dev->recv_list);

drivers/vhost/scsi.c

···
 };
 
 #define VHOST_SCSI_MAX_TARGET	256
-#define VHOST_SCSI_MAX_VQ	128
+#define VHOST_SCSI_MAX_IO_VQ	1024
 #define VHOST_SCSI_MAX_EVENT	128
+
+static unsigned vhost_scsi_max_io_vqs = 128;
+module_param_named(max_io_vqs, vhost_scsi_max_io_vqs, uint, 0644);
+MODULE_PARM_DESC(max_io_vqs, "Set the max number of IO virtqueues a vhost scsi device can support. The default is 128. The max is 1024.");
 
 struct vhost_scsi_virtqueue {
 	struct vhost_virtqueue vq;
···
 	char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 
 	struct vhost_dev dev;
-	struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
+	struct vhost_scsi_virtqueue *vqs;
+	unsigned long *compl_bitmap;
+	struct vhost_scsi_inflight **old_inflight;
 
 	struct vhost_work vs_completion_work; /* cmd completion work item */
 	struct llist_head vs_completion_list; /* cmd completion queue */
···
 	struct vhost_virtqueue *vq;
 	int idx, i;
 
-	for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
+	for (i = 0; i < vs->dev.nvqs;  i++) {
 		vq = &vs->vqs[i].vq;
 
 		mutex_lock(&vq->mutex);
···
 {
 	struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 					vs_completion_work);
-	DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 	struct virtio_scsi_cmd_resp v_rsp;
 	struct vhost_scsi_cmd *cmd, *t;
 	struct llist_node *llnode;
···
 	struct iov_iter iov_iter;
 	int ret, vq;
 
-	bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
+	bitmap_zero(vs->compl_bitmap, vs->dev.nvqs);
 	llnode = llist_del_all(&vs->vs_completion_list);
 	llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
 		se_cmd = &cmd->tvc_se_cmd;
···
 			vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 			q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 			vq = q - vs->vqs;
-			__set_bit(vq, signal);
+			__set_bit(vq, vs->compl_bitmap);
 		} else
 			pr_err("Faulted on virtio_scsi_cmd_resp\n");
 
···
 	}
 
 	vq = -1;
-	while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
-		< VHOST_SCSI_MAX_VQ)
+	while ((vq = find_next_bit(vs->compl_bitmap, vs->dev.nvqs, vq + 1))
+		< vs->dev.nvqs)
 		vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 }
 
···
 /* Callers must hold dev mutex */
 static void vhost_scsi_flush(struct vhost_scsi *vs)
 {
-	struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
 	int i;
 
 	/* Init new inflight and remember the old inflight */
-	vhost_scsi_init_inflight(vs, old_inflight);
+	vhost_scsi_init_inflight(vs, vs->old_inflight);
 
 	/*
 	 * The inflight->kref was initialized to 1. We decrement it here to
 	 * indicate the start of the flush operation so that it will reach 0
 	 * when all the reqs are finished.
 	 */
-	for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
-		kref_put(&old_inflight[i]->kref, vhost_scsi_done_inflight);
+	for (i = 0; i < vs->dev.nvqs; i++)
+		kref_put(&vs->old_inflight[i]->kref, vhost_scsi_done_inflight);
 
 	/* Flush both the vhost poll and vhost work */
 	vhost_dev_flush(&vs->dev);
 
 	/* Wait for all reqs issued before the flush to be finished */
-	for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
-		wait_for_completion(&old_inflight[i]->comp);
+	for (i = 0; i < vs->dev.nvqs; i++)
+		wait_for_completion(&vs->old_inflight[i]->comp);
 }
 
 static void vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue *vq)
···
 		memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
 		       sizeof(vs->vs_vhost_wwpn));
 
-		for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
+		for (i = VHOST_SCSI_VQ_IO; i < vs->dev.nvqs; i++) {
 			vq = &vs->vqs[i].vq;
 			if (!vhost_vq_is_setup(vq))
 				continue;
···
 				goto destroy_vq_cmds;
 		}
 
-		for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
+		for (i = 0; i < vs->dev.nvqs; i++) {
 			vq = &vs->vqs[i].vq;
 			mutex_lock(&vq->mutex);
 			vhost_vq_set_backend(vq, vs_tpg);
···
 		target_undepend_item(&se_tpg->tpg_group.cg_item);
 	}
 	if (match) {
-		for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
+		for (i = 0; i < vs->dev.nvqs; i++) {
 			vq = &vs->vqs[i].vq;
 			mutex_lock(&vq->mutex);
 			vhost_vq_set_backend(vq, NULL);
···
 		/* Make sure cmds are not running before tearing them down. */
 		vhost_scsi_flush(vs);
 
-		for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
+		for (i = 0; i < vs->dev.nvqs; i++) {
 			vq = &vs->vqs[i].vq;
 			vhost_scsi_destroy_vq_cmds(vq);
 		}
···
 		return -EFAULT;
 	}
 
-	for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
+	for (i = 0; i < vs->dev.nvqs; i++) {
 		vq = &vs->vqs[i].vq;
 		mutex_lock(&vq->mutex);
 		vq->acked_features = features;
···
 {
 	struct vhost_scsi *vs;
 	struct vhost_virtqueue **vqs;
-	int r = -ENOMEM, i;
+	int r = -ENOMEM, i, nvqs = vhost_scsi_max_io_vqs;
 
 	vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
 	if (!vs)
 		goto err_vs;
 
-	vqs = kmalloc_array(VHOST_SCSI_MAX_VQ, sizeof(*vqs), GFP_KERNEL);
-	if (!vqs)
+	if (nvqs > VHOST_SCSI_MAX_IO_VQ) {
+		pr_err("Invalid max_io_vqs of %d. Using %d.\n", nvqs,
+		       VHOST_SCSI_MAX_IO_VQ);
+		nvqs = VHOST_SCSI_MAX_IO_VQ;
+	} else if (nvqs == 0) {
+		pr_err("Invalid max_io_vqs of %d. Using 1.\n", nvqs);
+		nvqs = 1;
+	}
+	nvqs += VHOST_SCSI_VQ_IO;
+
+	vs->compl_bitmap = bitmap_alloc(nvqs, GFP_KERNEL);
+	if (!vs->compl_bitmap)
+		goto err_compl_bitmap;
+
+	vs->old_inflight = kmalloc_array(nvqs, sizeof(*vs->old_inflight),
+					 GFP_KERNEL | __GFP_ZERO);
+	if (!vs->old_inflight)
+		goto err_inflight;
+
+	vs->vqs = kmalloc_array(nvqs, sizeof(*vs->vqs),
+				GFP_KERNEL | __GFP_ZERO);
+	if (!vs->vqs)
 		goto err_vqs;
+
+	vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL);
+	if (!vqs)
+		goto err_local_vqs;
 
 	vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
 	vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
···
 	vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 	vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
 	vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
-	for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
+	for (i = VHOST_SCSI_VQ_IO; i < nvqs; i++) {
 		vqs[i] = &vs->vqs[i].vq;
 		vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
 	}
-	vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ, UIO_MAXIOV,
+	vhost_dev_init(&vs->dev, vqs, nvqs, UIO_MAXIOV,
 		       VHOST_SCSI_WEIGHT, 0, true, NULL);
 
 	vhost_scsi_init_inflight(vs, NULL);
···
 	f->private_data = vs;
 	return 0;
 
+err_local_vqs:
+	kfree(vs->vqs);
 err_vqs:
+	kfree(vs->old_inflight);
+err_inflight:
+	bitmap_free(vs->compl_bitmap);
+err_compl_bitmap:
 	kvfree(vs);
 err_vs:
 	return r;
···
 	vhost_dev_stop(&vs->dev);
 	vhost_dev_cleanup(&vs->dev);
 	kfree(vs->dev.vqs);
+	kfree(vs->vqs);
+	kfree(vs->old_inflight);
+	bitmap_free(vs->compl_bitmap);
 	kvfree(vs);
 	return 0;
 }

drivers/vhost/vdpa.c

···
 	return 0;
 }
 
+static bool vhost_vdpa_can_suspend(const struct vhost_vdpa *v)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	return ops->suspend;
+}
+
 static long vhost_vdpa_get_features(struct vhost_vdpa *v, u64 __user *featurep)
 {
 	struct vdpa_device *vdpa = v->vdpa;
···
 	return 0;
 }
 
+/* After a successful return of ioctl the device must not process more
+ * virtqueue descriptors. The device can answer to read or writes of config
+ * fields as if it were not suspended. In particular, writing to "queue_enable"
+ * with a value of 1 will not make the device start processing buffers.
+ */
+static long vhost_vdpa_suspend(struct vhost_vdpa *v)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	if (!ops->suspend)
+		return -EOPNOTSUPP;
+
+	return ops->suspend(vdpa);
+}
+
 static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
 				   void __user *argp)
 {
···
 	if (cmd == VHOST_SET_BACKEND_FEATURES) {
 		if (copy_from_user(&features, featurep, sizeof(features)))
 			return -EFAULT;
-		if (features & ~VHOST_VDPA_BACKEND_FEATURES)
+		if (features & ~(VHOST_VDPA_BACKEND_FEATURES |
+				 BIT_ULL(VHOST_BACKEND_F_SUSPEND)))
+			return -EOPNOTSUPP;
+		if ((features & BIT_ULL(VHOST_BACKEND_F_SUSPEND)) &&
+		     !vhost_vdpa_can_suspend(v))
 			return -EOPNOTSUPP;
 		vhost_set_backend_features(&v->vdev, features);
 		return 0;
···
 		break;
 	case VHOST_GET_BACKEND_FEATURES:
 		features = VHOST_VDPA_BACKEND_FEATURES;
+		if (vhost_vdpa_can_suspend(v))
+			features |= BIT_ULL(VHOST_BACKEND_F_SUSPEND);
 		if (copy_to_user(featurep, &features, sizeof(features)))
 			r = -EFAULT;
 		break;
···
 		break;
 	case VHOST_VDPA_GET_VQS_COUNT:
 		r = vhost_vdpa_get_vqs_count(v, argp);
+		break;
+	case VHOST_VDPA_SUSPEND:
+		r = vhost_vdpa_suspend(v);
 		break;
 	default:
 		r = vhost_dev_ioctl(&v->vdev, cmd, argp);
···
 	if (!bus)
 		return -EFAULT;
 
-	if (!iommu_capable(bus, IOMMU_CAP_CACHE_COHERENCY))
+	if (!device_iommu_capable(dma_dev, IOMMU_CAP_CACHE_COHERENCY))
 		return -ENOTSUPP;
 
 	v->domain = iommu_domain_alloc(bus);
···
 
 err:
 	put_device(&v->dev);
+	ida_simple_remove(&vhost_vdpa_ida, v->minor);
 	return r;
 }
 

drivers/vhost/vringh.c

···
 #if IS_REACHABLE(CONFIG_VHOST_IOTLB)
 
 static int iotlb_translate(const struct vringh *vrh,
-			   u64 addr, u64 len, struct bio_vec iov[],
+			   u64 addr, u64 len, u64 *translated,
+			   struct bio_vec iov[],
 			   int iov_size, u32 perm)
 {
 	struct vhost_iotlb_map *map;
···
 
 	spin_unlock(vrh->iotlb_lock);
 
+	if (translated)
+		*translated = min(len, s);
+
 	return ret;
 }
 
 static inline int copy_from_iotlb(const struct vringh *vrh, void *dst,
 				  void *src, size_t len)
 {
-	struct iov_iter iter;
-	struct bio_vec iov[16];
-	int ret;
+	u64 total_translated = 0;
 
-	ret = iotlb_translate(vrh, (u64)(uintptr_t)src,
-			      len, iov, 16, VHOST_MAP_RO);
-	if (ret < 0)
-		return ret;
+	while (total_translated < len) {
+		struct bio_vec iov[16];
+		struct iov_iter iter;
+		u64 translated;
+		int ret;
 
-	iov_iter_bvec(&iter, READ, iov, ret, len);
+		ret = iotlb_translate(vrh, (u64)(uintptr_t)src,
+				      len - total_translated, &translated,
+				      iov, ARRAY_SIZE(iov), VHOST_MAP_RO);
+		if (ret == -ENOBUFS)
+			ret = ARRAY_SIZE(iov);
+		else if (ret < 0)
+			return ret;
 
-	ret = copy_from_iter(dst, len, &iter);
+		iov_iter_bvec(&iter, READ, iov, ret, translated);
 
-	return ret;
+		ret = copy_from_iter(dst, translated, &iter);
+		if (ret < 0)
+			return ret;
+
+		src += translated;
+		dst += translated;
+		total_translated += translated;
+	}
+
+	return total_translated;
 }
 
 static inline int copy_to_iotlb(const struct vringh *vrh, void *dst,
 				void *src, size_t len)
 {
-	struct iov_iter iter;
-	struct bio_vec iov[16];
-	int ret;
+	u64 total_translated = 0;
 
-	ret = iotlb_translate(vrh, (u64)(uintptr_t)dst,
-			      len, iov, 16, VHOST_MAP_WO);
-	if (ret < 0)
-		return ret;
+	while (total_translated < len) {
+		struct bio_vec iov[16];
+		struct iov_iter iter;
+		u64 translated;
+		int ret;
 
-	iov_iter_bvec(&iter, WRITE, iov, ret, len);
+		ret = iotlb_translate(vrh, (u64)(uintptr_t)dst,
+				      len - total_translated, &translated,
+				      iov, ARRAY_SIZE(iov), VHOST_MAP_WO);
+		if (ret == -ENOBUFS)
+			ret = ARRAY_SIZE(iov);
+		else if (ret < 0)
+			return ret;
 
-	return copy_to_iter(src, len, &iter);
+		iov_iter_bvec(&iter, WRITE, iov, ret, translated);
+
+		ret = copy_to_iter(src, translated, &iter);
+		if (ret < 0)
+			return ret;
+
+		src += translated;
+		dst += translated;
+		total_translated += translated;
+	}
+
+	return total_translated;
 }
 
 static inline int getu16_iotlb(const struct vringh *vrh,
···
 	int ret;
 
 	/* Atomic read is needed for getu16 */
-	ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p),
+	ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), NULL,
 			      &iov, 1, VHOST_MAP_RO);
 	if (ret < 0)
 		return ret;
···
 	int ret;
 
 	/* Atomic write is needed for putu16 */
-	ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p),
+	ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), NULL,
 			      &iov, 1, VHOST_MAP_WO);
 	if (ret < 0)
 		return ret;

drivers/virtio/Kconfig

···
 
 config VIRTIO_HARDEN_NOTIFICATION
         bool "Harden virtio notification"
+        depends on BROKEN
         help
           Enable this to harden the device notifications and suppress
           those that happen at a time where notifications are illegal.
 
-          Experimental: Note that several drivers still have bugs that
+          Experimental: Note that several drivers still have issues that
           may cause crashes or hangs when correct handling of
           notifications is enforced; depending on the subset of
           drivers and devices you use, this may or may not work.
···
 	 This driver provides access to virtio-mem paravirtualized memory
 	 devices, allowing to hotplug and hotunplug memory.
 
-	 This driver was only tested under x86-64 and arm64, but should
-	 theoretically work on all architectures that support memory hotplug
-	 and hotremove.
+	 This driver currently only supports x86-64 and arm64. Although it
+	 should compile on other architectures that implement memory
+	 hot(un)plug, architecture-specific and/or common
+	 code changes may be required for virtio-mem, kdump and kexec to work as
+	 expected.
 
 	 If unsure, say M.
 

drivers/virtio/virtio.c

···
 		goto out;
 
 	dev->index = err;
-	dev_set_name(&dev->dev, "virtio%u", dev->index);
+	err = dev_set_name(&dev->dev, "virtio%u", dev->index);
+	if (err)
+		goto out_ida_remove;
 
 	err = virtio_device_of_init(dev);
 	if (err)

drivers/virtio/virtio_mmio.c

···
 
 static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned int index,
 				  void (*callback)(struct virtqueue *vq),
-				  const char *name, bool ctx)
+				  const char *name, u32 size, bool ctx)
 {
 	struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
 	struct virtio_mmio_vq_info *info;
···
 		goto error_new_virtqueue;
 	}
 
+	if (!size || size > num)
+		size = num;
+
 	/* Create the vring */
-	vq = vring_create_virtqueue(index, num, VIRTIO_MMIO_VRING_ALIGN, vdev,
+	vq = vring_create_virtqueue(index, size, VIRTIO_MMIO_VRING_ALIGN, vdev,
 				 true, true, ctx, vm_notify, callback, name);
 	if (!vq) {
 		err = -ENOMEM;
 		goto error_new_virtqueue;
 	}
+
+	vq->num_max = num;
 
 	/* Activate the queue */
 	writel(virtqueue_get_vring_size(vq), vm_dev->base + VIRTIO_MMIO_QUEUE_NUM);
···
 		       struct virtqueue *vqs[],
 		       vq_callback_t *callbacks[],
 		       const char * const names[],
+		       u32 sizes[],
 		       const bool *ctx,
 		       struct irq_affinity *desc)
 {
···
 	if (err)
 		return err;
 
+	if (of_property_read_bool(vm_dev->pdev->dev.of_node, "wakeup-source"))
+		enable_irq_wake(irq);
+
 	for (i = 0; i < nvqs; ++i) {
 		if (!names[i]) {
 			vqs[i] = NULL;
···
 		}
 
 		vqs[i] = vm_setup_vq(vdev, queue_idx++, callbacks[i], names[i],
+				     sizes ? sizes[i] : 0,
 				     ctx ? ctx[i] : false);
 		if (IS_ERR(vqs[i])) {
 			vm_del_vqs(vdev);

drivers/virtio/virtio_pci_common.c

···
 static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned int index,
 				     void (*callback)(struct virtqueue *vq),
 				     const char *name,
+				     u32 size,
 				     bool ctx,
 				     u16 msix_vec)
 {
···
 	if (!info)
 		return ERR_PTR(-ENOMEM);
 
-	vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, ctx,
+	vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, size, ctx,
 			      msix_vec);
 	if (IS_ERR(vq))
 		goto out_info;
···
 	struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index];
 	unsigned long flags;
 
-	spin_lock_irqsave(&vp_dev->lock, flags);
-	list_del(&info->node);
-	spin_unlock_irqrestore(&vp_dev->lock, flags);
+	/*
+	 * If it fails during re-enable reset vq. This way we won't rejoin
+	 * info->node to the queue. Prevent unexpected irqs.
+	 */
+	if (!vq->reset) {
+		spin_lock_irqsave(&vp_dev->lock, flags);
+		list_del(&info->node);
+		spin_unlock_irqrestore(&vp_dev->lock, flags);
+	}
 
 	vp_dev->del_vq(info);
 	kfree(info);
···
 
 static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned int nvqs,
 		struct virtqueue *vqs[], vq_callback_t *callbacks[],
-		const char * const names[], bool per_vq_vectors,
+		const char * const names[], u32 sizes[], bool per_vq_vectors,
 		const bool *ctx,
 		struct irq_affinity *desc)
 {
···
 		else
 			msix_vec = VP_MSIX_VQ_VECTOR;
 		vqs[i] = vp_setup_vq(vdev, queue_idx++, callbacks[i], names[i],
-				     ctx ? ctx[i] : false,
-				     msix_vec);
+				     sizes ? sizes[i] : 0,
+				     ctx ? ctx[i] : false, msix_vec);
 		if (IS_ERR(vqs[i])) {
 			err = PTR_ERR(vqs[i]);
 			goto error_find;
···
 
 static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned int nvqs,
 		struct virtqueue *vqs[], vq_callback_t *callbacks[],
-		const char * const names[], const bool *ctx)
+		const char * const names[], u32 sizes[], const bool *ctx)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	int i, err, queue_idx = 0;
···
 			continue;
 		}
 		vqs[i] = vp_setup_vq(vdev, queue_idx++, callbacks[i], names[i],
+				     sizes ? sizes[i] : 0,
 				     ctx ? ctx[i] : false,
 				     VIRTIO_MSI_NO_VECTOR);
 		if (IS_ERR(vqs[i])) {
···
 /* the config->find_vqs() implementation */
 int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
 		struct virtqueue *vqs[], vq_callback_t *callbacks[],
-		const char * const names[], const bool *ctx,
+		const char * const names[], u32 sizes[], const bool *ctx,
 		struct irq_affinity *desc)
 {
 	int err;
 
 	/* Try MSI-X with one vector per queue. */
-	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, true, ctx, desc);
+	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, sizes, true, ctx, desc);
 	if (!err)
 		return 0;
 	/* Fallback: MSI-X with one vector for config, one shared for queues. */
-	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, false, ctx, desc);
+	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, sizes, false, ctx, desc);
 	if (!err)
 		return 0;
 	/* Finally fall back to regular interrupts. */
-	return vp_find_vqs_intx(vdev, nvqs, vqs, callbacks, names, ctx);
+	return vp_find_vqs_intx(vdev, nvqs, vqs, callbacks, names, sizes, ctx);
 }
 
 const char *vp_bus_name(struct virtio_device *vdev)

drivers/virtio/virtio_pci_common.h

···
 				      unsigned int idx,
 				      void (*callback)(struct virtqueue *vq),
 				      const char *name,
+				      u32 size,
 				      bool ctx,
 				      u16 msix_vec);
 	void (*del_vq)(struct virtio_pci_vq_info *info);
···
 /* the config->find_vqs() implementation */
 int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
 		struct virtqueue *vqs[], vq_callback_t *callbacks[],
-		const char * const names[], const bool *ctx,
+		const char * const names[], u32 sizes[], const bool *ctx,
 		struct irq_affinity *desc);
 const char *vp_bus_name(struct virtio_device *vdev);
 

drivers/virtio/virtio_pci_legacy.c

···
 				  unsigned int index,
 				  void (*callback)(struct virtqueue *vq),
 				  const char *name,
+				  u32 size,
 				  bool ctx,
 				  u16 msix_vec)
 {
···
 	if (!num || vp_legacy_get_queue_enable(&vp_dev->ldev, index))
 		return ERR_PTR(-ENOENT);
 
+	if (!size || size > num)
+		size = num;
+
 	info->msix_vector = msix_vec;
 
 	/* create the vring */
-	vq = vring_create_virtqueue(index, num,
+	vq = vring_create_virtqueue(index, size,
 				    VIRTIO_PCI_VRING_ALIGN, &vp_dev->vdev,
 				    true, false, ctx,
 				    vp_notify, callback, name);
 	if (!vq)
 		return ERR_PTR(-ENOMEM);
+
+	vq->num_max = num;
 
 	q_pfn = virtqueue_get_desc_addr(vq) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT;
 	if (q_pfn >> 32) {

drivers/virtio/virtio_pci_modern.c

···
 	if ((features & BIT_ULL(VIRTIO_F_SR_IOV)) &&
 			pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV))
 		__virtio_set_bit(vdev, VIRTIO_F_SR_IOV);
+
+	if (features & BIT_ULL(VIRTIO_F_RING_RESET))
+		__virtio_set_bit(vdev, VIRTIO_F_RING_RESET);
 }
 
 /* virtio config->finalize_features() implementation */
···
 	vp_synchronize_vectors(vdev);
 }
 
+static int vp_active_vq(struct virtqueue *vq, u16 msix_vec)
+{
+	struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
+	struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+	unsigned long index;
+
+	index = vq->index;
+
+	/* activate the queue */
+	vp_modern_set_queue_size(mdev, index, virtqueue_get_vring_size(vq));
+	vp_modern_queue_address(mdev, index, virtqueue_get_desc_addr(vq),
+				virtqueue_get_avail_addr(vq),
+				virtqueue_get_used_addr(vq));
+
+	if (msix_vec != VIRTIO_MSI_NO_VECTOR) {
+		msix_vec = vp_modern_queue_vector(mdev, index, msix_vec);
+		if (msix_vec == VIRTIO_MSI_NO_VECTOR)
+			return -EBUSY;
+	}
+
+	return 0;
+}
+
+static int vp_modern_disable_vq_and_reset(struct virtqueue *vq)
+{
+	struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
+	struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+	struct virtio_pci_vq_info *info;
+	unsigned long flags;
+
+	if (!virtio_has_feature(vq->vdev, VIRTIO_F_RING_RESET))
+		return -ENOENT;
+
+	vp_modern_set_queue_reset(mdev, vq->index);
+
+	info = vp_dev->vqs[vq->index];
+
+	/* delete vq from irq handler */
+	spin_lock_irqsave(&vp_dev->lock, flags);
+	list_del(&info->node);
+	spin_unlock_irqrestore(&vp_dev->lock, flags);
+
+	INIT_LIST_HEAD(&info->node);
+
+#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
+	__virtqueue_break(vq);
+#endif
+
+	/* For the case where vq has an exclusive irq, call synchronize_irq() to
+	 * wait for completion.
+	 *
+	 * note: We can't use disable_irq() since it conflicts with the affinity
+	 * managed IRQ that is used by some drivers.
+	 */
+	if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR)
+		synchronize_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector));
+
+	vq->reset = true;
+
+	return 0;
+}
+
+static int vp_modern_enable_vq_after_reset(struct virtqueue *vq)
+{
+	struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
+	struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+	struct virtio_pci_vq_info *info;
+	unsigned long flags, index;
+	int err;
+
+	if (!vq->reset)
+		return -EBUSY;
+
+	index = vq->index;
+	info = vp_dev->vqs[index];
+
+	if (vp_modern_get_queue_reset(mdev, index))
+		return -EBUSY;
+
+	if (vp_modern_get_queue_enable(mdev, index))
+		return -EBUSY;
+
+	err = vp_active_vq(vq, info->msix_vector);
+	if (err)
+		return err;
+
+	if (vq->callback) {
+		spin_lock_irqsave(&vp_dev->lock, flags);
+		list_add(&info->node, &vp_dev->virtqueues);
+		spin_unlock_irqrestore(&vp_dev->lock, flags);
+	} else {
+		INIT_LIST_HEAD(&info->node);
+	}
+
+#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
+	__virtqueue_unbreak(vq);
+#endif
+
+	vp_modern_set_queue_enable(&vp_dev->mdev, index, true);
+	vq->reset = false;
+
+	return 0;
+}
+
 static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector)
 {
 	return vp_modern_config_vector(&vp_dev->mdev, vector);
···
 				  unsigned int index,
 				  void (*callback)(struct virtqueue *vq),
 				  const char *name,
+				  u32 size,
 				  bool ctx,
 				  u16 msix_vec)
 {
···
 	if (!num || vp_modern_get_queue_enable(mdev, index))
 		return ERR_PTR(-ENOENT);
 
-	if (num & (num - 1)) {
-		dev_warn(&vp_dev->pci_dev->dev, "bad queue size %u", num);
+	if (!size || size > num)
+		size = num;
+
+	if (size & (size - 1)) {
+		dev_warn(&vp_dev->pci_dev->dev, "bad queue size %u", size);
 		return ERR_PTR(-EINVAL);
 	}
 
 	info->msix_vector = msix_vec;
 
 	/* create the vring */
-	vq = vring_create_virtqueue(index, num,
+	vq = vring_create_virtqueue(index, size,
 				    SMP_CACHE_BYTES, &vp_dev->vdev,
 				    true, true, ctx,
 				    vp_notify, callback, name);
 	if (!vq)
 		return ERR_PTR(-ENOMEM);
 
-	/* activate the queue */
-	vp_modern_set_queue_size(mdev, index, virtqueue_get_vring_size(vq));
-	vp_modern_queue_address(mdev, index, virtqueue_get_desc_addr(vq),
-				virtqueue_get_avail_addr(vq),
-				virtqueue_get_used_addr(vq));
+	vq->num_max = num;
+
+	err = vp_active_vq(vq, msix_vec);
+	if (err)
+		goto err;
 
 	vq->priv = (void __force *)vp_modern_map_vq_notify(mdev, index, NULL);
 	if (!vq->priv) {
 		err = -ENOMEM;
-		goto err_map_notify;
-	}
-
-	if (msix_vec != VIRTIO_MSI_NO_VECTOR) {
-		msix_vec = vp_modern_queue_vector(mdev, index, msix_vec);
-		if (msix_vec == VIRTIO_MSI_NO_VECTOR) {
-			err = -EBUSY;
-			goto err_assign_vector;
-		}
+		goto err;
 	}
 
 	return vq;
 
-err_assign_vector:
-	if (!mdev->notify_base)
-		pci_iounmap(mdev->pci_dev, (void __iomem __force *)vq->priv);
-err_map_notify:
+err:
 	vring_del_virtqueue(vq);
 	return ERR_PTR(err);
 }
···
 static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
 			      struct virtqueue *vqs[],
 			      vq_callback_t *callbacks[],
-			      const char * const names[], const bool *ctx,
+			      const char * const names[],
+			      u32 sizes[],
+			      const bool *ctx,
 			      struct irq_affinity *desc)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	struct virtqueue *vq;
-	int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, ctx, desc);
+	int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, sizes, ctx,
+			     desc);
 
 	if (rc)
 		return rc;
···
 	.set_vq_affinity = vp_set_vq_affinity,
 	.get_vq_affinity = vp_get_vq_affinity,
 	.get_shm_region  = vp_get_shm_region,
+	.disable_vq_and_reset = vp_modern_disable_vq_and_reset,
+	.enable_vq_after_reset = vp_modern_enable_vq_after_reset,
 };
 
 static const struct virtio_config_ops virtio_pci_config_ops = {
···
 	.set_vq_affinity = vp_set_vq_affinity,
 	.get_vq_affinity = vp_get_vq_affinity,
 	.get_shm_region  = vp_get_shm_region,
+	.disable_vq_and_reset = vp_modern_disable_vq_and_reset,
+	.enable_vq_after_reset = vp_modern_enable_vq_after_reset,
 };
 
 /* the PCI probing function */

drivers/virtio/virtio_pci_modern_dev.c

···
 #include <linux/virtio_pci_modern.h>
 #include <linux/module.h>
 #include <linux/pci.h>
+#include <linux/delay.h>
 
 /*
  * vp_modern_map_capability - map a part of virtio pci capability
···
 	vp_iowrite8(status, &cfg->device_status);
 }
 EXPORT_SYMBOL_GPL(vp_modern_set_status);
+
+/*
+ * vp_modern_get_queue_reset - get the queue reset status
+ * @mdev: the modern virtio-pci device
+ * @index: queue index
+ */
+int vp_modern_get_queue_reset(struct virtio_pci_modern_device *mdev, u16 index)
+{
+	struct virtio_pci_modern_common_cfg __iomem *cfg;
+
+	cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common;
+
+	vp_iowrite16(index, &cfg->cfg.queue_select);
+	return vp_ioread16(&cfg->queue_reset);
+}
+EXPORT_SYMBOL_GPL(vp_modern_get_queue_reset);
+
+/*
+ * vp_modern_set_queue_reset - reset the queue
+ * @mdev: the modern virtio-pci device
+ * @index: queue index
+ */
+void vp_modern_set_queue_reset(struct virtio_pci_modern_device *mdev, u16 index)
+{
+	struct virtio_pci_modern_common_cfg __iomem *cfg;
+
+	cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common;
+
+	vp_iowrite16(index, &cfg->cfg.queue_select);
+	vp_iowrite16(1, &cfg->queue_reset);
+
+	while (vp_ioread16(&cfg->queue_reset))
+		msleep(1);
+
+	while (vp_ioread16(&cfg->cfg.queue_enable))
+		msleep(1);
+}
+EXPORT_SYMBOL_GPL(vp_modern_set_queue_reset);
 
 /*
  * vp_modern_queue_vector - set the MSIX vector for a specific virtqueue

drivers/virtio/virtio_ring.c

···
 	u16 next;			/* The next desc state in a list. */
 };
 
+struct vring_virtqueue_split {
+	/* Actual memory layout for this queue. */
+	struct vring vring;
+
+	/* Last written value to avail->flags */
+	u16 avail_flags_shadow;
+
+	/*
+	 * Last written value to avail->idx in
+	 * guest byte order.
+	 */
+	u16 avail_idx_shadow;
+
+	/* Per-descriptor state. */
+	struct vring_desc_state_split *desc_state;
+	struct vring_desc_extra *desc_extra;
+
+	/* DMA address and size information */
+	dma_addr_t queue_dma_addr;
+	size_t queue_size_in_bytes;
+
+	/*
+	 * The parameters for creating vrings are reserved for creating new
+	 * vring.
+	 */
+	u32 vring_align;
+	bool may_reduce_num;
+};
+
+struct vring_virtqueue_packed {
+	/* Actual memory layout for this queue. */
+	struct {
+		unsigned int num;
+		struct vring_packed_desc *desc;
+		struct vring_packed_desc_event *driver;
+		struct vring_packed_desc_event *device;
+	} vring;
+
+	/* Driver ring wrap counter. */
+	bool avail_wrap_counter;
+
+	/* Avail used flags. */
+	u16 avail_used_flags;
+
+	/* Index of the next avail descriptor. */
+	u16 next_avail_idx;
+
+	/*
+	 * Last written value to driver->flags in
+	 * guest byte order.
+	 */
+	u16 event_flags_shadow;
+
+	/* Per-descriptor state. */
+	struct vring_desc_state_packed *desc_state;
+	struct vring_desc_extra *desc_extra;
+
+	/* DMA address and size information */
+	dma_addr_t ring_dma_addr;
+	dma_addr_t driver_event_dma_addr;
+	dma_addr_t device_event_dma_addr;
+	size_t ring_size_in_bytes;
+	size_t event_size_in_bytes;
+};
+
 struct vring_virtqueue {
 	struct virtqueue vq;
 
···
 
 	union {
 		/* Available for split ring */
-		struct {
-			/* Actual memory layout for this queue. */
-			struct vring vring;
-
-			/* Last written value to avail->flags */
-			u16 avail_flags_shadow;
-
-			/*
-			 * Last written value to avail->idx in
-			 * guest byte order.
-			 */
-			u16 avail_idx_shadow;
-
-			/* Per-descriptor state. */
-			struct vring_desc_state_split *desc_state;
-			struct vring_desc_extra *desc_extra;
-
-			/* DMA address and size information */
-			dma_addr_t queue_dma_addr;
-			size_t queue_size_in_bytes;
-		} split;
+		struct vring_virtqueue_split split;
 
 		/* Available for packed ring */
-		struct {
-			/* Actual memory layout for this queue. */
-			struct {
-				unsigned int num;
-				struct vring_packed_desc *desc;
-				struct vring_packed_desc_event *driver;
-				struct vring_packed_desc_event *device;
-			} vring;
-
-			/* Driver ring wrap counter. */
-			bool avail_wrap_counter;
-
-			/* Avail used flags. */
-			u16 avail_used_flags;
-
-			/* Index of the next avail descriptor. */
-			u16 next_avail_idx;
-
-			/*
-			 * Last written value to driver->flags in
-			 * guest byte order.
-			 */
-			u16 event_flags_shadow;
-
-			/* Per-descriptor state. */
-			struct vring_desc_state_packed *desc_state;
-			struct vring_desc_extra *desc_extra;
-
-			/* DMA address and size information */
-			dma_addr_t ring_dma_addr;
-			dma_addr_t driver_event_dma_addr;
-			dma_addr_t device_event_dma_addr;
-			size_t ring_size_in_bytes;
-			size_t event_size_in_bytes;
-		} packed;
+		struct vring_virtqueue_packed packed;
 	};
 
 	/* How to notify other side. FIXME: commonalize hcalls! */
···
 #endif
 };
 
+static struct virtqueue *__vring_new_virtqueue(unsigned int index,
+					       struct vring_virtqueue_split *vring_split,
+					       struct virtio_device *vdev,
+					       bool weak_barriers,
+					       bool context,
+					       bool (*notify)(struct virtqueue *),
+					       void (*callback)(struct virtqueue *),
+					       const char *name);
+static struct vring_desc_extra *vring_alloc_desc_extra(unsigned int num);
+static void vring_free(struct virtqueue *_vq);
 
 /*
  * Helpers.
···
 		return 0;
 
 	return dma_mapping_error(vring_dma_dev(vq), addr);
+}
+
+static void virtqueue_init(struct vring_virtqueue *vq, u32 num)
+{
+	vq->vq.num_free = num;
+
+	if (vq->packed_ring)
+		vq->last_used_idx = 0 | (1 << VRING_PACKED_EVENT_F_WRAP_CTR);
+	else
+		vq->last_used_idx = 0;
+
+	vq->event_triggered = false;
+	vq->num_added = 0;
+
+#ifdef DEBUG
+	vq->in_use = false;
+	vq->last_add_time_valid = false;
+#endif
 }
 
 
···
 	return NULL;
 }
 
+static void virtqueue_vring_init_split(struct vring_virtqueue_split *vring_split,
+				       struct vring_virtqueue *vq)
+{
+	struct virtio_device *vdev;
+
+	vdev = vq->vq.vdev;
+
+	vring_split->avail_flags_shadow = 0;
+	vring_split->avail_idx_shadow = 0;
+
+	/* No callback?  Tell other side not to bother us. */
+	if (!vq->vq.callback) {
+		vring_split->avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT;
+		if (!vq->event)
+			vring_split->vring.avail->flags = cpu_to_virtio16(vdev,
+					vring_split->avail_flags_shadow);
+	}
+}
+
+static void virtqueue_reinit_split(struct vring_virtqueue *vq)
+{
+	int num;
+
+	num = vq->split.vring.num;
+
+	vq->split.vring.avail->flags = 0;
+	vq->split.vring.avail->idx = 0;
+
+	/* reset avail event */
+	vq->split.vring.avail->ring[num] = 0;
+
+	vq->split.vring.used->flags = 0;
+	vq->split.vring.used->idx = 0;
+
+	/* reset used event */
+	*(__virtio16 *)&(vq->split.vring.used->ring[num]) = 0;
+
+	virtqueue_init(vq, num);
+
+	virtqueue_vring_init_split(&vq->split, vq);
+}
+
+static void virtqueue_vring_attach_split(struct vring_virtqueue *vq,
+					 struct vring_virtqueue_split *vring_split)
+{
+	vq->split = *vring_split;
+
+	/* Put everything in free lists. */
+	vq->free_head = 0;
+}
+
+static int vring_alloc_state_extra_split(struct vring_virtqueue_split *vring_split)
+{
+	struct vring_desc_state_split *state;
+	struct vring_desc_extra *extra;
+	u32 num = vring_split->vring.num;
+
+	state = kmalloc_array(num, sizeof(struct vring_desc_state_split), GFP_KERNEL);
+	if (!state)
+		goto err_state;
+
+	extra = vring_alloc_desc_extra(num);
+	if (!extra)
+		goto err_extra;
+
+	memset(state, 0, num * sizeof(struct vring_desc_state_split));
+
+	vring_split->desc_state = state;
+	vring_split->desc_extra = extra;
+	return 0;
+
+err_extra:
+	kfree(state);
+err_state:
+	return -ENOMEM;
+}
+
+static void vring_free_split(struct vring_virtqueue_split *vring_split,
+			     struct virtio_device *vdev)
+{
+	vring_free_queue(vdev, vring_split->queue_size_in_bytes,
+			 vring_split->vring.desc,
+			 vring_split->queue_dma_addr);
+
+	kfree(vring_split->desc_state);
+	kfree(vring_split->desc_extra);
+}
+
+static int vring_alloc_queue_split(struct vring_virtqueue_split *vring_split,
+				   struct virtio_device *vdev,
+				   u32 num,
+				   unsigned int vring_align,
+				   bool may_reduce_num)
+{
+	void *queue = NULL;
+	dma_addr_t dma_addr;
+
+	/* We assume num is a power of 2. */
+	if (num & (num - 1)) {
+		dev_warn(&vdev->dev, "Bad virtqueue length %u\n", num);
+		return -EINVAL;
+	}
+
+	/* TODO: allocate each queue chunk individually */
+	for (; num && vring_size(num, vring_align) > PAGE_SIZE; num /= 2) {
+		queue = vring_alloc_queue(vdev, vring_size(num, vring_align),
+					  &dma_addr,
+					  GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO);
+		if (queue)
+			break;
+		if (!may_reduce_num)
+			return -ENOMEM;
+	}
+
+	if (!num)
+		return -ENOMEM;
+
+	if (!queue) {
+		/* Try to get a single page. You are my only hope! */
+		queue = vring_alloc_queue(vdev, vring_size(num, vring_align),
+					  &dma_addr, GFP_KERNEL|__GFP_ZERO);
+	}
+	if (!queue)
+		return -ENOMEM;
+
+	vring_init(&vring_split->vring, num, queue, vring_align);
+
+	vring_split->queue_dma_addr = dma_addr;
+	vring_split->queue_size_in_bytes = vring_size(num, vring_align);
+
+	vring_split->vring_align = vring_align;
+	vring_split->may_reduce_num = may_reduce_num;
+
+	return 0;
+}
+
 static struct virtqueue *vring_create_virtqueue_split(
 	unsigned int index,
 	unsigned int num,
···
 	void (*callback)(struct virtqueue *),
 	const char *name)
 {
+	struct vring_virtqueue_split vring_split = {};
 	struct virtqueue *vq;
-	void *queue = NULL;
-	dma_addr_t dma_addr;
-	size_t queue_size_in_bytes;
-	struct vring vring;
+	int err;
 
-	/* We assume num is a power of 2. */
-	if (num & (num - 1)) {
-		dev_warn(&vdev->dev, "Bad virtqueue length %u\n", num);
-		return NULL;
-	}
-
-	/* TODO: allocate each queue chunk individually */
-	for (; num && vring_size(num, vring_align) > PAGE_SIZE; num /= 2) {
-		queue = vring_alloc_queue(vdev, vring_size(num, vring_align),
-					  &dma_addr,
-					  GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO);
-		if (queue)
-			break;
-		if (!may_reduce_num)
-			return NULL;
-	}
-
-	if (!num)
+	err = vring_alloc_queue_split(&vring_split, vdev, num, vring_align,
+				      may_reduce_num);
+	if (err)
 		return NULL;
 
-	if (!queue) {
-		/* Try to get a single page. You are my only hope! */
-		queue = vring_alloc_queue(vdev, vring_size(num, vring_align),
-					  &dma_addr, GFP_KERNEL|__GFP_ZERO);
-	}
-	if (!queue)
-		return NULL;
-
-	queue_size_in_bytes = vring_size(num, vring_align);
-	vring_init(&vring, num, queue, vring_align);
-
-	vq = __vring_new_virtqueue(index, vring, vdev, weak_barriers, context,
-				   notify, callback, name);
+	vq = __vring_new_virtqueue(index, &vring_split, vdev, weak_barriers,
+				   context, notify, callback, name);
 	if (!vq) {
-		vring_free_queue(vdev, queue_size_in_bytes, queue,
-				 dma_addr);
+		vring_free_split(&vring_split, vdev);
 		return NULL;
 	}
 
-	to_vvq(vq)->split.queue_dma_addr = dma_addr;
-	to_vvq(vq)->split.queue_size_in_bytes = queue_size_in_bytes;
 	to_vvq(vq)->we_own_ring = true;
 
 	return vq;
+}
+
+static int virtqueue_resize_split(struct virtqueue *_vq, u32 num)
+{
+	struct vring_virtqueue_split vring_split = {};
+	struct vring_virtqueue *vq = to_vvq(_vq);
+	struct virtio_device *vdev = _vq->vdev;
+	int err;
+
+	err = vring_alloc_queue_split(&vring_split, vdev, num,
+				      vq->split.vring_align,
+				      vq->split.may_reduce_num);
+	if (err)
+		goto err;
+
+	err = vring_alloc_state_extra_split(&vring_split);
+	if (err)
+		goto err_state_extra;
+
+	vring_free(&vq->vq);
+
+	virtqueue_vring_init_split(&vring_split, vq);
+
+	virtqueue_init(vq, vring_split.vring.num);
+	virtqueue_vring_attach_split(vq, &vring_split);
+
+	return 0;
+
+err_state_extra:
+	vring_free_split(&vring_split, vdev);
+err:
+	virtqueue_reinit_split(vq);
+	return -ENOMEM;
 }
 
 
···
 	return NULL;
 }
 
-static struct vring_desc_extra *vring_alloc_desc_extra(struct vring_virtqueue *vq,
-						       unsigned int num)
+static struct vring_desc_extra *vring_alloc_desc_extra(unsigned int num)
 {
 	struct vring_desc_extra *desc_extra;
 	unsigned int i;
···
 	return desc_extra;
 }
 
+static void vring_free_packed(struct vring_virtqueue_packed *vring_packed,
+			      struct virtio_device *vdev)
+{
+	if (vring_packed->vring.desc)
+		vring_free_queue(vdev, vring_packed->ring_size_in_bytes,
+				 vring_packed->vring.desc,
+				 vring_packed->ring_dma_addr);
+
+	if (vring_packed->vring.driver)
+		vring_free_queue(vdev, vring_packed->event_size_in_bytes,
+				 vring_packed->vring.driver,
+				 vring_packed->driver_event_dma_addr);
+
+	if (vring_packed->vring.device)
+		vring_free_queue(vdev, vring_packed->event_size_in_bytes,
+				 vring_packed->vring.device,
+				 vring_packed->device_event_dma_addr);
+
+	kfree(vring_packed->desc_state);
+	kfree(vring_packed->desc_extra);
+}
+
+static int vring_alloc_queue_packed(struct vring_virtqueue_packed *vring_packed,
+				    struct virtio_device *vdev,
+				    u32 num)
+{
+	struct vring_packed_desc *ring;
+	struct vring_packed_desc_event *driver, *device;
+	dma_addr_t ring_dma_addr, driver_event_dma_addr, device_event_dma_addr;
+	size_t ring_size_in_bytes, event_size_in_bytes;
+
+	ring_size_in_bytes = num * sizeof(struct vring_packed_desc);
+
+	ring = vring_alloc_queue(vdev, ring_size_in_bytes,
+				 &ring_dma_addr,
+				 GFP_KERNEL|__GFP_NOWARN|__GFP_ZERO);
+	if (!ring)
+		goto err;
+
+	vring_packed->vring.desc         = ring;
+	vring_packed->ring_dma_addr      = ring_dma_addr;
+	vring_packed->ring_size_in_bytes = ring_size_in_bytes;
+
+	event_size_in_bytes = sizeof(struct vring_packed_desc_event);
+
+	driver = vring_alloc_queue(vdev, event_size_in_bytes,
+				   &driver_event_dma_addr,
+				   GFP_KERNEL|__GFP_NOWARN|__GFP_ZERO);
+	if (!driver)
+		goto err;
+
+	vring_packed->vring.driver          = driver;
+	vring_packed->event_size_in_bytes   = event_size_in_bytes;
+	vring_packed->driver_event_dma_addr = driver_event_dma_addr;
+
+	device = vring_alloc_queue(vdev, event_size_in_bytes,
+				   &device_event_dma_addr,
+				   GFP_KERNEL|__GFP_NOWARN|__GFP_ZERO);
+	if (!device)
+		goto err;
+
+	vring_packed->vring.device          = device;
+	vring_packed->device_event_dma_addr = device_event_dma_addr;
+
+	vring_packed->vring.num = num;
+
+	return 0;
+
+err:
+	vring_free_packed(vring_packed, vdev);
+	return -ENOMEM;
+}
+
+static int vring_alloc_state_extra_packed(struct vring_virtqueue_packed *vring_packed)
+{
+	struct vring_desc_state_packed *state;
+	struct vring_desc_extra *extra;
+	u32 num = vring_packed->vring.num;
+
+	state = kmalloc_array(num, sizeof(struct vring_desc_state_packed), GFP_KERNEL);
+	if (!state)
+		goto err_desc_state;
+
+	memset(state, 0, num * sizeof(struct vring_desc_state_packed));
+
+	extra = vring_alloc_desc_extra(num);
+	if (!extra)
+		goto err_desc_extra;
+
+	vring_packed->desc_state = state;
+	vring_packed->desc_extra = extra;
+
+	return 0;
+
+err_desc_extra:
+	kfree(state);
+err_desc_state:
+	return -ENOMEM;
+}
+
+static void virtqueue_vring_init_packed(struct vring_virtqueue_packed *vring_packed,
+					bool callback)
+{
+	vring_packed->next_avail_idx = 0;
+	vring_packed->avail_wrap_counter = 1;
+	vring_packed->event_flags_shadow = 0;
+	vring_packed->avail_used_flags = 1 << VRING_PACKED_DESC_F_AVAIL;
+
+	/* No callback?  Tell other side not to bother us. */
+	if (!callback) {
+		vring_packed->event_flags_shadow = VRING_PACKED_EVENT_FLAG_DISABLE;
+		vring_packed->vring.driver->flags =
+			cpu_to_le16(vring_packed->event_flags_shadow);
+	}
+}
+
+static void virtqueue_vring_attach_packed(struct vring_virtqueue *vq,
+					  struct vring_virtqueue_packed *vring_packed)
+{
+	vq->packed = *vring_packed;
+
+	/* Put everything in free lists. */
+	vq->free_head = 0;
+}
+
+static void virtqueue_reinit_packed(struct vring_virtqueue *vq)
+{
+	memset(vq->packed.vring.device, 0, vq->packed.event_size_in_bytes);
+	memset(vq->packed.vring.driver, 0, vq->packed.event_size_in_bytes);
+
+	/* we need to reset the desc.flags. For more, see is_used_desc_packed() */
+	memset(vq->packed.vring.desc, 0, vq->packed.ring_size_in_bytes);
+
+	virtqueue_init(vq, vq->packed.vring.num);
+	virtqueue_vring_init_packed(&vq->packed, !!vq->vq.callback);
+}
+
 static struct virtqueue *vring_create_virtqueue_packed(
 	unsigned int index,
 	unsigned int num,
···
 	void (*callback)(struct virtqueue *),
 	const char *name)
 {
+	struct vring_virtqueue_packed vring_packed = {};
 	struct vring_virtqueue *vq;
-	struct vring_packed_desc *ring;
-	struct vring_packed_desc_event *driver, *device;
-	dma_addr_t ring_dma_addr, driver_event_dma_addr, device_event_dma_addr;
-	size_t ring_size_in_bytes, event_size_in_bytes;
+	int err;
 
-	ring_size_in_bytes = num * sizeof(struct vring_packed_desc);
-
-	ring = vring_alloc_queue(vdev, ring_size_in_bytes,
-				 &ring_dma_addr,
-				 GFP_KERNEL|__GFP_NOWARN|__GFP_ZERO);
-	if (!ring)
+	if (vring_alloc_queue_packed(&vring_packed, vdev, num))
 		goto err_ring;
-
-	event_size_in_bytes = sizeof(struct vring_packed_desc_event);
-
-	driver = vring_alloc_queue(vdev, event_size_in_bytes,
-				   &driver_event_dma_addr,
-				   GFP_KERNEL|__GFP_NOWARN|__GFP_ZERO);
-	if (!driver)
-		goto err_driver;
-
-	device = vring_alloc_queue(vdev, event_size_in_bytes,
-				   &device_event_dma_addr,
-				   GFP_KERNEL|__GFP_NOWARN|__GFP_ZERO);
-	if (!device)
-		goto err_device;
 
 	vq = kmalloc(sizeof(*vq), GFP_KERNEL);
 	if (!vq)
···
 	vq->vq.callback = callback;
 	vq->vq.vdev = vdev;
 	vq->vq.name = name;
-	vq->vq.num_free = num;
 	vq->vq.index = index;
+	vq->vq.reset = false;
 	vq->we_own_ring = true;
 	vq->notify = notify;
 	vq->weak_barriers = weak_barriers;
···
 #else
 	vq->broken = false;
 #endif
-	vq->last_used_idx = 0 | (1 << VRING_PACKED_EVENT_F_WRAP_CTR);
-	vq->event_triggered = false;
-	vq->num_added = 0;
 	vq->packed_ring = true;
 	vq->use_dma_api = vring_use_dma_api(vdev);
-#ifdef DEBUG
-	vq->in_use = false;
-	vq->last_add_time_valid = false;
-#endif
 
 	vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) &&
 		!context;
···
 	if (virtio_has_feature(vdev, VIRTIO_F_ORDER_PLATFORM))
 		vq->weak_barriers = false;
 
-	vq->packed.ring_dma_addr = ring_dma_addr;
-	vq->packed.driver_event_dma_addr = driver_event_dma_addr;
-	vq->packed.device_event_dma_addr = device_event_dma_addr;
+	err = vring_alloc_state_extra_packed(&vring_packed);
+	if (err)
+		goto err_state_extra;
 
-	vq->packed.ring_size_in_bytes = ring_size_in_bytes;
-	vq->packed.event_size_in_bytes = event_size_in_bytes;
+	virtqueue_vring_init_packed(&vring_packed, !!callback);
 
-	vq->packed.vring.num = num;
-	vq->packed.vring.desc = ring;
-	vq->packed.vring.driver = driver;
-	vq->packed.vring.device = device;
-
-	vq->packed.next_avail_idx = 0;
-	vq->packed.avail_wrap_counter = 1;
-	vq->packed.event_flags_shadow = 0;
-	vq->packed.avail_used_flags = 1 << VRING_PACKED_DESC_F_AVAIL;
-
-	vq->packed.desc_state = kmalloc_array(num,
-			sizeof(struct vring_desc_state_packed),
-			GFP_KERNEL);
-	if (!vq->packed.desc_state)
-		goto err_desc_state;
-
-	memset(vq->packed.desc_state, 0,
-		num * sizeof(struct vring_desc_state_packed));
-
-	/* Put everything in free lists. */
-	vq->free_head = 0;
-
-	vq->packed.desc_extra = vring_alloc_desc_extra(vq, num);
-	if (!vq->packed.desc_extra)
-		goto err_desc_extra;
-
-	/* No callback?  Tell other side not to bother us. */
-	if (!callback) {
-		vq->packed.event_flags_shadow = VRING_PACKED_EVENT_FLAG_DISABLE;
-		vq->packed.vring.driver->flags =
-			cpu_to_le16(vq->packed.event_flags_shadow);
-	}
+	virtqueue_init(vq, num);
+	virtqueue_vring_attach_packed(vq, &vring_packed);
 
 	spin_lock(&vdev->vqs_list_lock);
 	list_add_tail(&vq->vq.list, &vdev->vqs);
 	spin_unlock(&vdev->vqs_list_lock);
 	return &vq->vq;
 
-err_desc_extra:
-	kfree(vq->packed.desc_state);
-err_desc_state:
+err_state_extra:
 	kfree(vq);
 err_vq:
-	vring_free_queue(vdev, event_size_in_bytes, device, device_event_dma_addr);
-err_device:
-	vring_free_queue(vdev, event_size_in_bytes, driver, driver_event_dma_addr);
-err_driver:
-	vring_free_queue(vdev, ring_size_in_bytes, ring, ring_dma_addr);
+	vring_free_packed(&vring_packed, vdev);
 err_ring:
 	return NULL;
+}
+
+static int virtqueue_resize_packed(struct virtqueue *_vq, u32 num)
+{
+	struct vring_virtqueue_packed vring_packed = {};
+	struct vring_virtqueue *vq = to_vvq(_vq);
+	struct virtio_device *vdev = _vq->vdev;
+	int err;
+
+	if (vring_alloc_queue_packed(&vring_packed, vdev, num))
+		goto err_ring;
+
+	err = vring_alloc_state_extra_packed(&vring_packed);
+	if (err)
+		goto err_state_extra;
+
+	vring_free(&vq->vq);
+
+	virtqueue_vring_init_packed(&vring_packed, !!vq->vq.callback);
+
+	virtqueue_init(vq, vring_packed.vring.num);
+	virtqueue_vring_attach_packed(vq, &vring_packed);
+
+	return 0;
+
+err_state_extra:
+	vring_free_packed(&vring_packed, vdev);
+err_ring:
+	virtqueue_reinit_packed(vq);
+	return -ENOMEM;
 }
 
 
···
  * @_vq: the struct virtqueue we're talking about.
  *
  * Returns NULL or the "data" token handed to virtqueue_add_*().
- * This is not valid on an active queue; it is useful only for device
- * shutdown.
+ * This is not valid on an active queue; it is useful for device
+ * shutdown or the reset queue.
  */
 void *virtqueue_detach_unused_buf(struct virtqueue *_vq)
 {
···
 EXPORT_SYMBOL_GPL(vring_interrupt);
 
 /* Only available for split ring */
-struct virtqueue *__vring_new_virtqueue(unsigned int index,
-					struct vring vring,
-					struct virtio_device *vdev,
-					bool weak_barriers,
-					bool context,
-					bool (*notify)(struct virtqueue *),
-					void (*callback)(struct virtqueue *),
-					const char *name)
+static struct virtqueue *__vring_new_virtqueue(unsigned int index,
+					       struct vring_virtqueue_split *vring_split,
+					       struct virtio_device *vdev,
+					       bool weak_barriers,
+					       bool context,
+					       bool (*notify)(struct virtqueue *),
+					       void (*callback)(struct virtqueue *),
+					       const char *name)
 {
 	struct vring_virtqueue *vq;
+	int err;
 
 	if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED))
 		return NULL;
···
 	vq->vq.callback = callback;
 	vq->vq.vdev = vdev;
 	vq->vq.name = name;
-	vq->vq.num_free = vring.num;
 	vq->vq.index = index;
+	vq->vq.reset = false;
 	vq->we_own_ring = false;
 	vq->notify = notify;
 	vq->weak_barriers = weak_barriers;
···
 #else
 	vq->broken = false;
 #endif
-	vq->last_used_idx = 0;
-	vq->event_triggered = false;
-	vq->num_added = 0;
 	vq->use_dma_api = vring_use_dma_api(vdev);
-#ifdef DEBUG
-	vq->in_use = false;
-	vq->last_add_time_valid = false;
-#endif
 
 	vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) &&
 		!context;
···
 	if (virtio_has_feature(vdev, VIRTIO_F_ORDER_PLATFORM))
 		vq->weak_barriers = false;
 
-	vq->split.queue_dma_addr = 0;
-	vq->split.queue_size_in_bytes = 0;
-
-	vq->split.vring = vring;
-	vq->split.avail_flags_shadow = 0;
-	vq->split.avail_idx_shadow = 0;
-
-	/* No callback?  Tell other side not to bother us. */
-	if (!callback) {
-		vq->split.avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT;
-		if (!vq->event)
-			vq->split.vring.avail->flags = cpu_to_virtio16(vdev,
-					vq->split.avail_flags_shadow);
+	err = vring_alloc_state_extra_split(vring_split);
+	if (err) {
+		kfree(vq);
+		return NULL;
 	}
 
-	vq->split.desc_state = kmalloc_array(vring.num,
-			sizeof(struct vring_desc_state_split), GFP_KERNEL);
-	if (!vq->split.desc_state)
-		goto err_state;
+	virtqueue_vring_init_split(vring_split, vq);
 
-	vq->split.desc_extra = vring_alloc_desc_extra(vq, vring.num);
-	if (!vq->split.desc_extra)
-		goto err_extra;
-
-	/* Put everything in free lists. */
-	vq->free_head = 0;
-	memset(vq->split.desc_state, 0, vring.num *
-			sizeof(struct vring_desc_state_split));
+	virtqueue_init(vq, vring_split->vring.num);
+	virtqueue_vring_attach_split(vq, vring_split);
 
 	spin_lock(&vdev->vqs_list_lock);
 	list_add_tail(&vq->vq.list, &vdev->vqs);
 	spin_unlock(&vdev->vqs_list_lock);
 	return &vq->vq;
-
-err_extra:
-	kfree(vq->split.desc_state);
-err_state:
-	kfree(vq);
-	return NULL;
 }
-EXPORT_SYMBOL_GPL(__vring_new_virtqueue);
 
 struct virtqueue *vring_create_virtqueue(
 	unsigned int index,
···
 }
 EXPORT_SYMBOL_GPL(vring_create_virtqueue);
 
+/**
+ * virtqueue_resize - resize the vring of vq
+ * @_vq: the struct virtqueue we're talking about.
+ * @num: new ring num
+ * @recycle: callback for recycle the useless buffer
+ *
+ * When it is really necessary to create a new vring, it will set the current vq
+ * into the reset state. Then call the passed callback to recycle the buffer
+ * that is no longer used. Only after the new vring is successfully created, the
+ * old vring will be released.
+ *
+ * Caller must ensure we don't call this with other virtqueue operations
+ * at the same time (except where noted).
+ *
+ * Returns zero or a negative error.
+ * 0: success.
+ * -ENOMEM: Failed to allocate a new ring, fall back to the original ring size.
+ *  vq can still work normally
+ * -EBUSY: Failed to sync with device, vq may not work properly
+ * -ENOENT: Transport or device not supported
+ * -E2BIG/-EINVAL: num error
+ * -EPERM: Operation not permitted
+ *
+ */
+int virtqueue_resize(struct virtqueue *_vq, u32 num,
+		     void (*recycle)(struct virtqueue *vq, void *buf))
+{
+	struct vring_virtqueue *vq = to_vvq(_vq);
+	struct virtio_device *vdev = vq->vq.vdev;
+	void *buf;
+	int err;
+
+	if (!vq->we_own_ring)
+		return -EPERM;
+
+	if (num > vq->vq.num_max)
+		return -E2BIG;
+
+	if (!num)
+		return -EINVAL;
+
+	if ((vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num) == num)
+		return 0;
+
+	if (!vdev->config->disable_vq_and_reset)
+		return -ENOENT;
+
+	if (!vdev->config->enable_vq_after_reset)
+		return -ENOENT;
+
+	err = vdev->config->disable_vq_and_reset(_vq);
+	if (err)
+		return err;
+
+	while ((buf = virtqueue_detach_unused_buf(_vq)) != NULL)
+		recycle(_vq, buf);
+
+	if (vq->packed_ring)
+		err = virtqueue_resize_packed(_vq, num);
+	else
+		err = virtqueue_resize_split(_vq, num);
+
+	if (vdev->config->enable_vq_after_reset(_vq))
+		return -EBUSY;
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(virtqueue_resize);
+
 /* Only available for split ring */
 struct virtqueue *vring_new_virtqueue(unsigned int index,
 				      unsigned int num,
···
 				      void (*callback)(struct virtqueue *vq),
 				      const char *name)
 {
-	struct vring vring;
+	struct vring_virtqueue_split vring_split = {};
 
 	if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED))
 		return NULL;
 
-	vring_init(&vring, num, pages, vring_align);
-	return __vring_new_virtqueue(index, vring, vdev, weak_barriers, context,
-				     notify, callback, name);
+	vring_init(&vring_split.vring, num, pages, vring_align);
+	return __vring_new_virtqueue(index, &vring_split, vdev, weak_barriers,
+				     context, notify, callback, name);
 }
 EXPORT_SYMBOL_GPL(vring_new_virtqueue);
 
-void vring_del_virtqueue(struct virtqueue *_vq)
+static void vring_free(struct virtqueue *_vq)
 {
 	struct vring_virtqueue *vq = to_vvq(_vq);
-
-	spin_lock(&vq->vq.vdev->vqs_list_lock);
-	list_del(&_vq->list);
-	spin_unlock(&vq->vq.vdev->vqs_list_lock);
 
 	if (vq->we_own_ring) {
 		if (vq->packed_ring) {
···
 		kfree(vq->split.desc_state);
 		kfree(vq->split.desc_extra);
 	}
+}
+
+void vring_del_virtqueue(struct virtqueue *_vq)
+{
+	struct vring_virtqueue *vq = to_vvq(_vq);
+
+	spin_lock(&vq->vq.vdev->vqs_list_lock);
+	list_del(&_vq->list);
+	spin_unlock(&vq->vq.vdev->vqs_list_lock);
+
+	vring_free(_vq);
+
 	kfree(vq);
 }
 EXPORT_SYMBOL_GPL(vring_del_virtqueue);
···
 	return vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num;
 }
 EXPORT_SYMBOL_GPL(virtqueue_get_vring_size);
+
+/*
+ * This function should only be called by the core, not directly by the driver.
+ */
+void __virtqueue_break(struct virtqueue *_vq)
+{
+	struct vring_virtqueue *vq = to_vvq(_vq);
+
+	/* Pairs with READ_ONCE() in virtqueue_is_broken(). */
+	WRITE_ONCE(vq->broken, true);
+}
+EXPORT_SYMBOL_GPL(__virtqueue_break);
+
+/*
+ * This function should only be called by the core, not directly by the driver.
+ */
+void __virtqueue_unbreak(struct virtqueue *_vq)
+{
+	struct vring_virtqueue *vq = to_vvq(_vq);
+
+	/* Pairs with READ_ONCE() in virtqueue_is_broken(). */
+	WRITE_ONCE(vq->broken, false);
+}
+EXPORT_SYMBOL_GPL(__virtqueue_unbreak);
 
 bool virtqueue_is_broken(struct virtqueue *_vq)
 {

drivers/virtio/virtio_vdpa.c

···
 static struct virtqueue *
 virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
 		     void (*callback)(struct virtqueue *vq),
-		     const char *name, bool ctx)
+		     const char *name, u32 size, bool ctx)
 {
 	struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vdev);
 	struct vdpa_device *vdpa = vd_get_vdpa(vdev);
···
 		goto error_new_virtqueue;
 	}
 
+	if (!size || size > max_num)
+		size = max_num;
+
 	if (ops->get_vq_num_min)
 		min_num = ops->get_vq_num_min(vdpa);
 
-	may_reduce_num = (max_num == min_num) ? false : true;
+	may_reduce_num = (size == min_num) ? false : true;
 
 	/* Create the vring */
 	align = ops->get_vq_align(vdpa);
-	vq = vring_create_virtqueue(index, max_num, align, vdev,
+	vq = vring_create_virtqueue(index, size, align, vdev,
 				    true, may_reduce_num, ctx,
 				    virtio_vdpa_notify, callback, name);
 	if (!vq) {
 		err = -ENOMEM;
 		goto error_new_virtqueue;
 	}
+
+	vq->num_max = max_num;
 
 	/* Setup virtqueue callback */
 	cb.callback = callback ? virtio_vdpa_virtqueue_cb : NULL;
···
 				struct virtqueue *vqs[],
 				vq_callback_t *callbacks[],
 				const char * const names[],
+				u32 sizes[],
 				const bool *ctx,
 				struct irq_affinity *desc)
 {
···
 			continue;
 		}
 
-		vqs[i] = virtio_vdpa_setup_vq(vdev, queue_idx++,
-					      callbacks[i], names[i], ctx ?
-					      ctx[i] : false);
+		vqs[i] = virtio_vdpa_setup_vq(vdev, queue_idx++, callbacks[i],
+						  names[i], sizes ? sizes[i] : 0,
+						  ctx ? ctx[i] : false);
 		if (IS_ERR(vqs[i])) {
 			err = PTR_ERR(vqs[i]);
 			goto err_setup_vq;

include/linux/mlx5/mlx5_ifc_vdpa.h

···
 	MLX5_VIRTIO_NET_Q_OBJECT_STATE_ERR      = 0x3,
 };
 
+/* This indicates that the object was not created or has already
+ * been desroyed. It is very safe to assume that this object will never
+ * have so many states
+ */
+enum {
+	MLX5_VIRTIO_NET_Q_OBJECT_NONE = 0xffffffff
+};
+
 enum {
 	MLX5_RQTC_LIST_Q_TYPE_RQ            = 0x0,
 	MLX5_RQTC_LIST_Q_TYPE_VIRTIO_NET_Q  = 0x1,

include/linux/remoteproc.h

···
 /**
  * struct rproc_vring - remoteproc vring state
  * @va:	virtual address
- * @len: length, in bytes
+ * @num: vring size
  * @da: device address
  * @align: vring alignment
  * @notifyid: rproc-specific unique vring index
···
  */
 struct rproc_vring {
 	void *va;
-	int len;
+	int num;
 	u32 da;
 	u32 align;
 	int notifyid;

include/linux/vdpa.h

···
  * @reset:			Reset device
  *				@vdev: vdpa device
  *				Returns integer: success (0) or error (< 0)
+ * @suspend:			Suspend or resume the device (optional)
+ *				@vdev: vdpa device
+ *				Returns integer: success (0) or error (< 0)
  * @get_config_size:		Get the size of the configuration space includes
  *				fields that are conditional on feature bits.
  *				@vdev: vdpa device
···
 	u8 (*get_status)(struct vdpa_device *vdev);
 	void (*set_status)(struct vdpa_device *vdev, u8 status);
 	int (*reset)(struct vdpa_device *vdev);
+	int (*suspend)(struct vdpa_device *vdev);
 	size_t (*get_config_size)(struct vdpa_device *vdev);
 	void (*get_config)(struct vdpa_device *vdev, unsigned int offset,
 			   void *buf, unsigned int len);

include/linux/virtio.h

···
  * @priv: a pointer for the virtqueue implementation to use.
  * @index: the zero-based ordinal number for this queue.
  * @num_free: number of elements we expect to be able to fit.
+ * @num_max: the maximum number of elements supported by the device.
+ * @reset: vq is in reset state or not.
  *
  * A note on @num_free: with indirect buffers, each buffer needs one
  * element in the queue, otherwise a buffer will need one element per
···
 	struct virtio_device *vdev;
 	unsigned int index;
 	unsigned int num_free;
+	unsigned int num_max;
 	void *priv;
+	bool reset;
 };
 
 int virtqueue_add_outbuf(struct virtqueue *vq,
···
 dma_addr_t virtqueue_get_avail_addr(struct virtqueue *vq);
 dma_addr_t virtqueue_get_used_addr(struct virtqueue *vq);
 
+int virtqueue_resize(struct virtqueue *vq, u32 num,
+		     void (*recycle)(struct virtqueue *vq, void *buf));
+
 /**
  * virtio_device - representation of a device using virtio
  * @index: unique position on the virtio bus
···
 
 void virtio_break_device(struct virtio_device *dev);
 void __virtio_unbreak_device(struct virtio_device *dev);
+
+void __virtqueue_break(struct virtqueue *_vq);
+void __virtqueue_unbreak(struct virtqueue *_vq);
 
 void virtio_config_changed(struct virtio_device *dev);
 #ifdef CONFIG_PM_SLEEP

include/linux/virtio_config.h

···
  *		include a NULL entry for vqs that do not need a callback
  *	names: array of virtqueue names (mainly for debugging)
  *		include a NULL entry for vqs unused by driver
+ *	sizes: array of virtqueue sizes
  *	Returns 0 on success or error status
  * @del_vqs: free virtqueues found by find_vqs().
  * @synchronize_cbs: synchronize with the virtqueue callbacks (optional)
···
  * @set_vq_affinity: set the affinity for a virtqueue (optional).
  * @get_vq_affinity: get the affinity for a virtqueue (optional).
  * @get_shm_region: get a shared memory region based on the index.
+ * @disable_vq_and_reset: reset a queue individually (optional).
+ *	vq: the virtqueue
+ *	Returns 0 on success or error status
+ *	disable_vq_and_reset will guarantee that the callbacks are disabled and
+ *	synchronized.
+ *	Except for the callback, the caller should guarantee that the vring is
+ *	not accessed by any functions of virtqueue.
+ * @enable_vq_after_reset: enable a reset queue
+ *	vq: the virtqueue
+ *	Returns 0 on success or error status
+ *	If disable_vq_and_reset is set, then enable_vq_after_reset must also be
+ *	set.
  */
 typedef void vq_callback_t(struct virtqueue *);
 struct virtio_config_ops {
···
 	void (*reset)(struct virtio_device *vdev);
 	int (*find_vqs)(struct virtio_device *, unsigned nvqs,
 			struct virtqueue *vqs[], vq_callback_t *callbacks[],
-			const char * const names[], const bool *ctx,
+			const char * const names[],
+			u32 sizes[],
+			const bool *ctx,
 			struct irq_affinity *desc);
 	void (*del_vqs)(struct virtio_device *);
 	void (*synchronize_cbs)(struct virtio_device *);
···
 			int index);
 	bool (*get_shm_region)(struct virtio_device *vdev,
 			       struct virtio_shm_region *region, u8 id);
+	int (*disable_vq_and_reset)(struct virtqueue *vq);
+	int (*enable_vq_after_reset)(struct virtqueue *vq);
 };
 
 /* If driver didn't advertise the feature, it will never appear. */
···
 	const char *names[] = { n };
 	struct virtqueue *vq;
 	int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names, NULL,
-					 NULL);
+					 NULL, NULL);
 	if (err < 0)
 		return ERR_PTR(err);
 	return vq;
···
 			const char * const names[],
 			struct irq_affinity *desc)
 {
-	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, NULL, desc);
+	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, NULL,
+				      NULL, desc);
 }
 
 static inline
···
 			const char * const names[], const bool *ctx,
 			struct irq_affinity *desc)
 {
-	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, ctx,
-				      desc);
+	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, NULL,
+				      ctx, desc);
+}
+
+static inline
+int virtio_find_vqs_ctx_size(struct virtio_device *vdev, u32 nvqs,
+			     struct virtqueue *vqs[],
+			     vq_callback_t *callbacks[],
+			     const char * const names[],
+			     u32 sizes[],
+			     const bool *ctx, struct irq_affinity *desc)
+{
+	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, sizes,
+				      ctx, desc);
 }
 
 /**

include/linux/virtio_pci_modern.h

···
 #include <linux/pci.h>
 #include <linux/virtio_pci.h>
 
+struct virtio_pci_modern_common_cfg {
+	struct virtio_pci_common_cfg cfg;
+
+	__le16 queue_notify_data;	/* read-write */
+	__le16 queue_reset;		/* read-write */
+};
+
 struct virtio_pci_modern_device {
 	struct pci_dev *pci_dev;
 
···
 				       u16 index, resource_size_t *pa);
 int vp_modern_probe(struct virtio_pci_modern_device *mdev);
 void vp_modern_remove(struct virtio_pci_modern_device *mdev);
+int vp_modern_get_queue_reset(struct virtio_pci_modern_device *mdev, u16 index);
+void vp_modern_set_queue_reset(struct virtio_pci_modern_device *mdev, u16 index);
 #endif

include/linux/virtio_ring.h

···
 					 void (*callback)(struct virtqueue *vq),
 					 const char *name);
 
-/* Creates a virtqueue with a custom layout. */
-struct virtqueue *__vring_new_virtqueue(unsigned int index,
-					struct vring vring,
-					struct virtio_device *vdev,
-					bool weak_barriers,
-					bool ctx,
-					bool (*notify)(struct virtqueue *),
-					void (*callback)(struct virtqueue *),
-					const char *name);
-
 /*
  * Creates a virtqueue with a standard layout but a caller-allocated
  * ring.

include/uapi/linux/vduse.h

···
  */
 #define VDUSE_VQ_INJECT_IRQ	_IOW(VDUSE_BASE, 0x17, __u32)
 
+/**
+ * struct vduse_iova_umem - userspace memory configuration for one IOVA region
+ * @uaddr: start address of userspace memory, it must be aligned to page size
+ * @iova: start of the IOVA region
+ * @size: size of the IOVA region
+ * @reserved: for future use, needs to be initialized to zero
+ *
+ * Structure used by VDUSE_IOTLB_REG_UMEM and VDUSE_IOTLB_DEREG_UMEM
+ * ioctls to register/de-register userspace memory for IOVA regions
+ */
+struct vduse_iova_umem {
+	__u64 uaddr;
+	__u64 iova;
+	__u64 size;
+	__u64 reserved[3];
+};
+
+/* Register userspace memory for IOVA regions */
+#define VDUSE_IOTLB_REG_UMEM	_IOW(VDUSE_BASE, 0x18, struct vduse_iova_umem)
+
+/* De-register the userspace memory. Caller should set iova and size field. */
+#define VDUSE_IOTLB_DEREG_UMEM	_IOW(VDUSE_BASE, 0x19, struct vduse_iova_umem)
+
+/**
+ * struct vduse_iova_info - information of one IOVA region
+ * @start: start of the IOVA region
+ * @last: last of the IOVA region
+ * @capability: capability of the IOVA regsion
+ * @reserved: for future use, needs to be initialized to zero
+ *
+ * Structure used by VDUSE_IOTLB_GET_INFO ioctl to get information of
+ * one IOVA region.
+ */
+struct vduse_iova_info {
+	__u64 start;
+	__u64 last;
+#define VDUSE_IOVA_CAP_UMEM (1 << 0)
+	__u64 capability;
+	__u64 reserved[3];
+};
+
+/*
+ * Find the first IOVA region that overlaps with the range [start, last]
+ * and return some information on it. Caller should set start and last fields.
+ */
+#define VDUSE_IOTLB_GET_INFO	_IOWR(VDUSE_BASE, 0x1a, struct vduse_iova_info)
+
 /* The control messages definition for read(2)/write(2) on /dev/vduse/$NAME */
 
 /**

include/uapi/linux/vhost.h

···
 #define VHOST_VDPA_SET_GROUP_ASID	_IOW(VHOST_VIRTIO, 0x7C, \
 					     struct vhost_vring_state)
 
+/* Suspend a device so it does not process virtqueue requests anymore
+ *
+ * After the return of ioctl the device must preserve all the necessary state
+ * (the virtqueue vring base plus the possible device specific states) that is
+ * required for restoring in the future. The device must not change its
+ * configuration after that point.
+ */
+#define VHOST_VDPA_SUSPEND		_IO(VHOST_VIRTIO, 0x7D)
+
 #endif

include/uapi/linux/vhost_types.h

···
  * message
  */
 #define VHOST_BACKEND_F_IOTLB_ASID  0x3
+/* Device can be suspended */
+#define VHOST_BACKEND_F_SUSPEND  0x4
 
 #endif

include/uapi/linux/virtio_config.h

···
  * rest are per-device feature bits.
  */
 #define VIRTIO_TRANSPORT_F_START	28
-#define VIRTIO_TRANSPORT_F_END		38
+#define VIRTIO_TRANSPORT_F_END		41
 
 #ifndef VIRTIO_CONFIG_NO_LEGACY
 /* Do we get callbacks when the ring is completely used, even if we've
···
  * Does the device support Single Root I/O Virtualization?
  */
 #define VIRTIO_F_SR_IOV			37
+
+/*
+ * This feature indicates that the driver can reset a queue individually.
+ */
+#define VIRTIO_F_RING_RESET		40
 #endif /* _UAPI_LINUX_VIRTIO_CONFIG_H */

include/uapi/linux/virtio_net.h

···
 #define VIRTIO_NET_F_MQ	22	/* Device supports Receive Flow
 					 * Steering */
 #define VIRTIO_NET_F_CTRL_MAC_ADDR 23	/* Set MAC address */
-
+#define VIRTIO_NET_F_NOTF_COAL	53	/* Guest can handle notifications coalescing */
 #define VIRTIO_NET_F_HASH_REPORT  57	/* Supports hash report */
 #define VIRTIO_NET_F_RSS	  60	/* Supports RSS RX steering */
 #define VIRTIO_NET_F_RSC_EXT	  61	/* extended coalescing info */
···
  */
 #define VIRTIO_NET_CTRL_GUEST_OFFLOADS   5
 #define VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET        0
+
+/*
+ * Control notifications coalescing.
+ *
+ * Request the device to change the notifications coalescing parameters.
+ *
+ * Available with the VIRTIO_NET_F_NOTF_COAL feature bit.
+ */
+#define VIRTIO_NET_CTRL_NOTF_COAL		6
+/*
+ * Set the tx-usecs/tx-max-packets patameters.
+ * tx-usecs - Maximum number of usecs to delay a TX notification.
+ * tx-max-packets - Maximum number of packets to send before a TX notification.
+ */
+struct virtio_net_ctrl_coal_tx {
+	__le32 tx_max_packets;
+	__le32 tx_usecs;
+};
+
+#define VIRTIO_NET_CTRL_NOTF_COAL_TX_SET		0
+
+/*
+ * Set the rx-usecs/rx-max-packets patameters.
+ * rx-usecs - Maximum number of usecs to delay a RX notification.
+ * rx-max-frames - Maximum number of packets to receive before a RX notification.
+ */
+struct virtio_net_ctrl_coal_rx {
+	__le32 rx_max_packets;
+	__le32 rx_usecs;
+};
+
+#define VIRTIO_NET_CTRL_NOTF_COAL_RX_SET		1
 
 #endif /* _UAPI_LINUX_VIRTIO_NET_H */

include/uapi/linux/virtio_pci.h

···
 #define VIRTIO_PCI_COMMON_Q_AVAILHI	44
 #define VIRTIO_PCI_COMMON_Q_USEDLO	48
 #define VIRTIO_PCI_COMMON_Q_USEDHI	52
+#define VIRTIO_PCI_COMMON_Q_NDATA	56
+#define VIRTIO_PCI_COMMON_Q_RESET	58
 
 #endif /* VIRTIO_PCI_NO_MODERN */
 

tools/virtio/linux/kernel.h

···
 #define READ                    0
 #define WRITE                   1
 
-typedef unsigned long long phys_addr_t;
 typedef unsigned long long dma_addr_t;
 typedef size_t __kernel_size_t;
 typedef unsigned int __wsum;
···
 #endif
 #define dev_err(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
 #define dev_warn(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
+#define dev_warn_once(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
 
 #define min(x, y) ({				\
 	typeof(x) _min1 = (x);			\

tools/virtio/linux/vringh.h

···
+#include <limits.h>
 #include "../../../include/linux/vringh.h"

tools/virtio/virtio_test.c

···
 
 	memset(info->ring, 0, vring_size(num, 4096));
 	vring_init(&info->vring, num, info->ring, 4096);
-	info->vq = __vring_new_virtqueue(info->idx, info->vring, vdev, true,
-					 false, vq_notify, vq_callback, "test");
+	info->vq = vring_new_virtqueue(info->idx, num, 4096, vdev, true, false,
+				       info->ring, vq_notify, vq_callback, "test");
 	assert(info->vq);
 	info->vq->priv = info;
 }