Merge branch 'virtio' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus

* 'virtio' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus: (27 commits)
  drivers/char: Eliminate use after free
  virtio: console: Accept console size along with resize control message
  virtio: console: Store each console's size in the console structure
  virtio: console: Resize console port 0 on config intr only if multiport is off
  virtio: console: Add support for nonblocking write()s
  virtio: console: Rename wait_is_over() to will_read_block()
  virtio: console: Don't always create a port 0 if using multiport
  virtio: console: Use a control message to add ports
  virtio: console: Move code around for future patches
  virtio: console: Remove config work handler
  virtio: console: Don't call hvc_remove() on unplugging console ports
  virtio: console: Return -EPIPE to hvc_console if we lost the connection
  virtio: console: Let host know of port or device add failures
  virtio: console: Add a __send_control_msg() that can send messages without a valid port
  virtio: Revert "virtio: disable multiport console support."
  virtio: add_buf_gfp
  trans_virtio: use virtqueue_xxx wrappers
  virtio-rng: use virtqueue_xxx wrappers
  virtio_ring: remove a level of indirection
  virtio_net: use virtqueue_xxx wrappers
  ...

Fix up conflicts in drivers/net/virtio_net.c due to new virtqueue_xxx
wrappers changes conflicting with some other cleanups.

drivers/block/virtio_blk.c

@@ -50,7 +50,7 @@ static void blk_done(struct virtqueue *vq)
 	unsigned long flags;
 
 	spin_lock_irqsave(&vblk->lock, flags);
-	while ((vbr = vblk->vq->vq_ops->get_buf(vblk->vq, &len)) != NULL) {
+	while ((vbr = virtqueue_get_buf(vblk->vq, &len)) != NULL) {
 		int error;
 
 		switch (vbr->status) {
@@ -70,6 +70,8 @@ static void blk_done(struct virtqueue *vq)
 			vbr->req->sense_len = vbr->in_hdr.sense_len;
 			vbr->req->errors = vbr->in_hdr.errors;
 		}
+		if (blk_special_request(vbr->req))
+			vbr->req->errors = (error != 0);
 
 		__blk_end_request_all(vbr->req, error);
 		list_del(&vbr->list);
@@ -103,6 +105,11 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
 		vbr->out_hdr.sector = 0;
 		vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
 		break;
+	case REQ_TYPE_SPECIAL:
+		vbr->out_hdr.type = VIRTIO_BLK_T_GET_ID;
+		vbr->out_hdr.sector = 0;
+		vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
+		break;
 	case REQ_TYPE_LINUX_BLOCK:
 		if (req->cmd[0] == REQ_LB_OP_FLUSH) {
 			vbr->out_hdr.type = VIRTIO_BLK_T_FLUSH;
@@ -151,7 +158,7 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
 		}
 	}
 
-	if (vblk->vq->vq_ops->add_buf(vblk->vq, vblk->sg, out, in, vbr) < 0) {
+	if (virtqueue_add_buf(vblk->vq, vblk->sg, out, in, vbr) < 0) {
 		mempool_free(vbr, vblk->pool);
 		return false;
 	}
@@ -180,7 +187,7 @@ static void do_virtblk_request(struct request_queue *q)
 	}
 
 	if (issued)
-		vblk->vq->vq_ops->kick(vblk->vq);
+		virtqueue_kick(vblk->vq);
 }
 
 static void virtblk_prepare_flush(struct request_queue *q, struct request *req)
@@ -189,12 +196,45 @@ static void virtblk_prepare_flush(struct request_queue *q, struct request *req)
 	req->cmd[0] = REQ_LB_OP_FLUSH;
 }
 
+/* return id (s/n) string for *disk to *id_str
+ */
+static int virtblk_get_id(struct gendisk *disk, char *id_str)
+{
+	struct virtio_blk *vblk = disk->private_data;
+	struct request *req;
+	struct bio *bio;
+
+	bio = bio_map_kern(vblk->disk->queue, id_str, VIRTIO_BLK_ID_BYTES,
+			   GFP_KERNEL);
+	if (IS_ERR(bio))
+		return PTR_ERR(bio);
+
+	req = blk_make_request(vblk->disk->queue, bio, GFP_KERNEL);
+	if (IS_ERR(req)) {
+		bio_put(bio);
+		return PTR_ERR(req);
+	}
+
+	req->cmd_type = REQ_TYPE_SPECIAL;
+	return blk_execute_rq(vblk->disk->queue, vblk->disk, req, false);
+}
+
 static int virtblk_ioctl(struct block_device *bdev, fmode_t mode,
 			 unsigned cmd, unsigned long data)
 {
 	struct gendisk *disk = bdev->bd_disk;
 	struct virtio_blk *vblk = disk->private_data;
 
+	if (cmd == 0x56424944) { /* 'VBID' */
+		void __user *usr_data = (void __user *)data;
+		char id_str[VIRTIO_BLK_ID_BYTES];
+		int err;
+
+		err = virtblk_get_id(disk, id_str);
+		if (!err && copy_to_user(usr_data, id_str, VIRTIO_BLK_ID_BYTES))
+			err = -EFAULT;
+		return err;
+	}
 	/*
 	 * Only allow the generic SCSI ioctls if the host can support it.
 	 */

drivers/char/hw_random/virtio-rng.c

@@ -32,7 +32,7 @@ static bool busy;
 static void random_recv_done(struct virtqueue *vq)
 {
 	/* We can get spurious callbacks, e.g. shared IRQs + virtio_pci. */
-	if (!vq->vq_ops->get_buf(vq, &data_avail))
+	if (!virtqueue_get_buf(vq, &data_avail))
 		return;
 
 	complete(&have_data);
@@ -46,10 +46,10 @@ static void register_buffer(u8 *buf, size_t size)
 	sg_init_one(&sg, buf, size);
 
 	/* There should always be room for one buffer. */
-	if (vq->vq_ops->add_buf(vq, &sg, 0, 1, buf) < 0)
+	if (virtqueue_add_buf(vq, &sg, 0, 1, buf) < 0)
 		BUG();
 
-	vq->vq_ops->kick(vq);
+	virtqueue_kick(vq);
 }
 
 static int virtio_read(struct hwrng *rng, void *buf, size_t size, bool wait)

drivers/net/virtio_net.c

@@ -122,7 +122,7 @@ static void skb_xmit_done(struct virtqueue *svq)
 	struct virtnet_info *vi = svq->vdev->priv;
 
 	/* Suppress further interrupts. */
-	svq->vq_ops->disable_cb(svq);
+	virtqueue_disable_cb(svq);
 
 	/* We were probably waiting for more output buffers. */
 	netif_wake_queue(vi->dev);
@@ -210,7 +210,7 @@ static int receive_mergeable(struct virtnet_info *vi, struct sk_buff *skb)
 			return -EINVAL;
 		}
 
-		page = vi->rvq->vq_ops->get_buf(vi->rvq, &len);
+		page = virtqueue_get_buf(vi->rvq, &len);
 		if (!page) {
 			pr_debug("%s: rx error: %d buffers missing\n",
 				 skb->dev->name, hdr->mhdr.num_buffers);
@@ -340,7 +340,7 @@ static int add_recvbuf_small(struct virtnet_info *vi, gfp_t gfp)
 
 	skb_to_sgvec(skb, vi->rx_sg + 1, 0, skb->len);
 
-	err = vi->rvq->vq_ops->add_buf(vi->rvq, vi->rx_sg, 0, 2, skb);
+	err = virtqueue_add_buf(vi->rvq, vi->rx_sg, 0, 2, skb);
 	if (err < 0)
 		dev_kfree_skb(skb);
 
@@ -385,7 +385,7 @@ static int add_recvbuf_big(struct virtnet_info *vi, gfp_t gfp)
 
 	/* chain first in list head */
 	first->private = (unsigned long)list;
-	err = vi->rvq->vq_ops->add_buf(vi->rvq, vi->rx_sg, 0, MAX_SKB_FRAGS + 2,
+	err = virtqueue_add_buf(vi->rvq, vi->rx_sg, 0, MAX_SKB_FRAGS + 2,
 				       first);
 	if (err < 0)
 		give_pages(vi, first);
@@ -404,7 +404,7 @@ static int add_recvbuf_mergeable(struct virtnet_info *vi, gfp_t gfp)
 
 	sg_init_one(vi->rx_sg, page_address(page), PAGE_SIZE);
 
-	err = vi->rvq->vq_ops->add_buf(vi->rvq, vi->rx_sg, 0, 1, page);
+	err = virtqueue_add_buf(vi->rvq, vi->rx_sg, 0, 1, page);
 	if (err < 0)
 		give_pages(vi, page);
 
@@ -433,7 +433,7 @@ static bool try_fill_recv(struct virtnet_info *vi, gfp_t gfp)
 	} while (err > 0);
 	if (unlikely(vi->num > vi->max))
 		vi->max = vi->num;
-	vi->rvq->vq_ops->kick(vi->rvq);
+	virtqueue_kick(vi->rvq);
 	return !oom;
 }
 
@@ -442,7 +442,7 @@ static void skb_recv_done(struct virtqueue *rvq)
 	struct virtnet_info *vi = rvq->vdev->priv;
 	/* Schedule NAPI, Suppress further interrupts if successful. */
 	if (napi_schedule_prep(&vi->napi)) {
-		rvq->vq_ops->disable_cb(rvq);
+		virtqueue_disable_cb(rvq);
 		__napi_schedule(&vi->napi);
 	}
 }
@@ -471,7 +471,7 @@ static int virtnet_poll(struct napi_struct *napi, int budget)
 
 again:
 	while (received < budget &&
-	       (buf = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) {
+	       (buf = virtqueue_get_buf(vi->rvq, &len)) != NULL) {
 		receive_buf(vi->dev, buf, len);
 		--vi->num;
 		received++;
@@ -485,9 +485,9 @@ static int virtnet_poll(struct napi_struct *napi, int budget)
 	/* Out of packets? */
 	if (received < budget) {
 		napi_complete(napi);
-		if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq)) &&
+		if (unlikely(!virtqueue_enable_cb(vi->rvq)) &&
 		    napi_schedule_prep(napi)) {
-			vi->rvq->vq_ops->disable_cb(vi->rvq);
+			virtqueue_disable_cb(vi->rvq);
 			__napi_schedule(napi);
 			goto again;
 		}
@@ -501,7 +501,7 @@ static unsigned int free_old_xmit_skbs(struct virtnet_info *vi)
 	struct sk_buff *skb;
 	unsigned int len, tot_sgs = 0;
 
-	while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) {
+	while ((skb = virtqueue_get_buf(vi->svq, &len)) != NULL) {
 		pr_debug("Sent skb %p\n", skb);
 		vi->dev->stats.tx_bytes += skb->len;
 		vi->dev->stats.tx_packets++;
@@ -554,7 +554,7 @@ static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
 		sg_set_buf(vi->tx_sg, &hdr->hdr, sizeof hdr->hdr);
 
 	hdr->num_sg = skb_to_sgvec(skb, vi->tx_sg + 1, 0, skb->len) + 1;
-	return vi->svq->vq_ops->add_buf(vi->svq, vi->tx_sg, hdr->num_sg,
+	return virtqueue_add_buf(vi->svq, vi->tx_sg, hdr->num_sg,
 					0, skb);
 }
 
@@ -574,14 +574,14 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
 	if (unlikely(capacity < 0)) {
 		netif_stop_queue(dev);
 		dev_warn(&dev->dev, "Unexpected full queue\n");
-		if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
-			vi->svq->vq_ops->disable_cb(vi->svq);
+		if (unlikely(!virtqueue_enable_cb(vi->svq))) {
+			virtqueue_disable_cb(vi->svq);
 			netif_start_queue(dev);
 			goto again;
 		}
 		return NETDEV_TX_BUSY;
 	}
-	vi->svq->vq_ops->kick(vi->svq);
+	virtqueue_kick(vi->svq);
 
 	/* Don't wait up for transmitted skbs to be freed. */
 	skb_orphan(skb);
@@ -591,12 +591,12 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
 	 * before it gets out of hand.  Naturally, this wastes entries. */
 	if (capacity < 2+MAX_SKB_FRAGS) {
 		netif_stop_queue(dev);
-		if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
+		if (unlikely(!virtqueue_enable_cb(vi->svq))) {
 			/* More just got used, free them then recheck. */
 			capacity += free_old_xmit_skbs(vi);
 			if (capacity >= 2+MAX_SKB_FRAGS) {
 				netif_start_queue(dev);
-				vi->svq->vq_ops->disable_cb(vi->svq);
+				virtqueue_disable_cb(vi->svq);
 			}
 		}
 	}
@@ -641,7 +641,7 @@ static int virtnet_open(struct net_device *dev)
 	 * now.  virtnet_poll wants re-enable the queue, so we disable here.
 	 * We synchronize against interrupts via NAPI_STATE_SCHED */
 	if (napi_schedule_prep(&vi->napi)) {
-		vi->rvq->vq_ops->disable_cb(vi->rvq);
+		virtqueue_disable_cb(vi->rvq);
 		__napi_schedule(&vi->napi);
 	}
 	return 0;
@@ -678,15 +678,15 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
 		sg_set_buf(&sg[i + 1], sg_virt(s), s->length);
 	sg_set_buf(&sg[out + in - 1], &status, sizeof(status));
 
-	BUG_ON(vi->cvq->vq_ops->add_buf(vi->cvq, sg, out, in, vi) < 0);
+	BUG_ON(virtqueue_add_buf(vi->cvq, sg, out, in, vi) < 0);
 
-	vi->cvq->vq_ops->kick(vi->cvq);
+	virtqueue_kick(vi->cvq);
 
 	/*
 	 * Spin for a response, the kick causes an ioport write, trapping
 	 * into the hypervisor, so the request should be handled immediately.
 	 */
-	while (!vi->cvq->vq_ops->get_buf(vi->cvq, &tmp))
+	while (!virtqueue_get_buf(vi->cvq, &tmp))
 		cpu_relax();
 
 	return status == VIRTIO_NET_OK;
@@ -1003,13 +1003,13 @@ static void free_unused_bufs(struct virtnet_info *vi)
 {
 	void *buf;
 	while (1) {
-		buf = vi->svq->vq_ops->detach_unused_buf(vi->svq);
+		buf = virtqueue_detach_unused_buf(vi->svq);
 		if (!buf)
 			break;
 		dev_kfree_skb(buf);
 	}
 	while (1) {
-		buf = vi->rvq->vq_ops->detach_unused_buf(vi->rvq);
+		buf = virtqueue_detach_unused_buf(vi->rvq);
 		if (!buf)
 			break;
 		if (vi->mergeable_rx_bufs || vi->big_packets)

drivers/virtio/virtio_balloon.c

@@ -75,7 +75,7 @@ static void balloon_ack(struct virtqueue *vq)
 	struct virtio_balloon *vb;
 	unsigned int len;
 
-	vb = vq->vq_ops->get_buf(vq, &len);
+	vb = virtqueue_get_buf(vq, &len);
 	if (vb)
 		complete(&vb->acked);
 }
@@ -89,9 +89,9 @@ static void tell_host(struct virtio_balloon *vb, struct virtqueue *vq)
 	init_completion(&vb->acked);
 
 	/* We should always be able to add one buffer to an empty queue. */
-	if (vq->vq_ops->add_buf(vq, &sg, 1, 0, vb) < 0)
+	if (virtqueue_add_buf(vq, &sg, 1, 0, vb) < 0)
 		BUG();
-	vq->vq_ops->kick(vq);
+	virtqueue_kick(vq);
 
 	/* When host has read buffer, this completes via balloon_ack */
 	wait_for_completion(&vb->acked);
@@ -204,7 +204,7 @@ static void stats_request(struct virtqueue *vq)
 	struct virtio_balloon *vb;
 	unsigned int len;
 
-	vb = vq->vq_ops->get_buf(vq, &len);
+	vb = virtqueue_get_buf(vq, &len);
 	if (!vb)
 		return;
 	vb->need_stats_update = 1;
@@ -221,9 +221,9 @@ static void stats_handle_request(struct virtio_balloon *vb)
 
 	vq = vb->stats_vq;
 	sg_init_one(&sg, vb->stats, sizeof(vb->stats));
-	if (vq->vq_ops->add_buf(vq, &sg, 1, 0, vb) < 0)
+	if (virtqueue_add_buf(vq, &sg, 1, 0, vb) < 0)
 		BUG();
-	vq->vq_ops->kick(vq);
+	virtqueue_kick(vq);
 }
 
 static void virtballoon_changed(struct virtio_device *vdev)
@@ -314,10 +314,9 @@ static int virtballoon_probe(struct virtio_device *vdev)
 		 * use it to signal us later.
 		 */
 		sg_init_one(&sg, vb->stats, sizeof vb->stats);
-		if (vb->stats_vq->vq_ops->add_buf(vb->stats_vq,
-						  &sg, 1, 0, vb) < 0)
+		if (virtqueue_add_buf(vb->stats_vq, &sg, 1, 0, vb) < 0)
 			BUG();
-		vb->stats_vq->vq_ops->kick(vb->stats_vq);
+		virtqueue_kick(vb->stats_vq);
 	}
 
 	vb->thread = kthread_run(balloon, vb, "vballoon");

drivers/virtio/virtio_ring.c

@@ -110,13 +110,14 @@ struct vring_virtqueue
 static int vring_add_indirect(struct vring_virtqueue *vq,
 			      struct scatterlist sg[],
 			      unsigned int out,
-			      unsigned int in)
+			      unsigned int in,
+			      gfp_t gfp)
 {
 	struct vring_desc *desc;
 	unsigned head;
 	int i;
 
-	desc = kmalloc((out + in) * sizeof(struct vring_desc), GFP_ATOMIC);
+	desc = kmalloc((out + in) * sizeof(struct vring_desc), gfp);
 	if (!desc)
 		return vq->vring.num;
 
@@ -155,11 +156,12 @@ static int vring_add_indirect(struct vring_virtqueue *vq,
 	return head;
 }
 
-static int vring_add_buf(struct virtqueue *_vq,
-			 struct scatterlist sg[],
-			 unsigned int out,
-			 unsigned int in,
-			 void *data)
+int virtqueue_add_buf_gfp(struct virtqueue *_vq,
+			  struct scatterlist sg[],
+			  unsigned int out,
+			  unsigned int in,
+			  void *data,
+			  gfp_t gfp)
 {
 	struct vring_virtqueue *vq = to_vvq(_vq);
 	unsigned int i, avail, head, uninitialized_var(prev);
@@ -171,7 +173,7 @@ static int vring_add_buf(struct virtqueue *_vq,
 	/* If the host supports indirect descriptor tables, and we have multiple
 	 * buffers, then go indirect. FIXME: tune this threshold */
 	if (vq->indirect && (out + in) > 1 && vq->num_free) {
-		head = vring_add_indirect(vq, sg, out, in);
+		head = vring_add_indirect(vq, sg, out, in, gfp);
 		if (head != vq->vring.num)
 			goto add_head;
 	}
@@ -232,8 +234,9 @@ static int vring_add_buf(struct virtqueue *_vq,
 		return vq->num_free ? vq->vring.num : 0;
 	return vq->num_free;
 }
+EXPORT_SYMBOL_GPL(virtqueue_add_buf_gfp);
 
-static void vring_kick(struct virtqueue *_vq)
+void virtqueue_kick(struct virtqueue *_vq)
 {
 	struct vring_virtqueue *vq = to_vvq(_vq);
 	START_USE(vq);
@@ -253,6 +256,7 @@ static void vring_kick(struct virtqueue *_vq)
 
 	END_USE(vq);
 }
+EXPORT_SYMBOL_GPL(virtqueue_kick);
 
 static void detach_buf(struct vring_virtqueue *vq, unsigned int head)
 {
@@ -284,7 +288,7 @@ static inline bool more_used(const struct vring_virtqueue *vq)
 	return vq->last_used_idx != vq->vring.used->idx;
 }
 
-static void *vring_get_buf(struct virtqueue *_vq, unsigned int *len)
+void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len)
 {
 	struct vring_virtqueue *vq = to_vvq(_vq);
 	void *ret;
@@ -325,15 +329,17 @@ static void *vring_get_buf(struct virtqueue *_vq, unsigned int *len)
 	END_USE(vq);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(virtqueue_get_buf);
 
-static void vring_disable_cb(struct virtqueue *_vq)
+void virtqueue_disable_cb(struct virtqueue *_vq)
 {
 	struct vring_virtqueue *vq = to_vvq(_vq);
 
 	vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
 }
+EXPORT_SYMBOL_GPL(virtqueue_disable_cb);
 
-static bool vring_enable_cb(struct virtqueue *_vq)
+bool virtqueue_enable_cb(struct virtqueue *_vq)
 {
 	struct vring_virtqueue *vq = to_vvq(_vq);
 
@@ -351,8 +357,9 @@ static bool vring_enable_cb(struct virtqueue *_vq)
 	END_USE(vq);
 	return true;
 }
+EXPORT_SYMBOL_GPL(virtqueue_enable_cb);
 
-static void *vring_detach_unused_buf(struct virtqueue *_vq)
+void *virtqueue_detach_unused_buf(struct virtqueue *_vq)
 {
 	struct vring_virtqueue *vq = to_vvq(_vq);
 	unsigned int i;
@@ -375,6 +382,7 @@ static void *vring_detach_unused_buf(struct virtqueue *_vq)
 	END_USE(vq);
 	return NULL;
 }
+EXPORT_SYMBOL_GPL(virtqueue_detach_unused_buf);
 
 irqreturn_t vring_interrupt(int irq, void *_vq)
 {
@@ -396,15 +404,6 @@ irqreturn_t vring_interrupt(int irq, void *_vq)
 }
 EXPORT_SYMBOL_GPL(vring_interrupt);
 
-static struct virtqueue_ops vring_vq_ops = {
-	.add_buf = vring_add_buf,
-	.get_buf = vring_get_buf,
-	.kick = vring_kick,
-	.disable_cb = vring_disable_cb,
-	.enable_cb = vring_enable_cb,
-	.detach_unused_buf = vring_detach_unused_buf,
-};
-
 struct virtqueue *vring_new_virtqueue(unsigned int num,
 				      unsigned int vring_align,
 				      struct virtio_device *vdev,
@@ -429,7 +428,6 @@ struct virtqueue *vring_new_virtqueue(unsigned int num,
 	vring_init(&vq->vring, num, pages, vring_align);
 	vq->vq.callback = callback;
 	vq->vq.vdev = vdev;
-	vq->vq.vq_ops = &vring_vq_ops;
 	vq->vq.name = name;
 	vq->notify = notify;
 	vq->broken = false;

include/linux/virtio.h

@@ -7,6 +7,7 @@
 #include <linux/spinlock.h>
 #include <linux/device.h>
 #include <linux/mod_devicetable.h>
+#include <linux/gfp.h>
 
 /**
  * virtqueue - a queue to register buffers for sending or receiving.
@@ -14,7 +15,6 @@
  * @callback: the function to call when buffers are consumed (can be NULL).
  * @name: the name of this virtqueue (mainly for debugging)
  * @vdev: the virtio device this queue was created for.
- * @vq_ops: the operations for this virtqueue (see below).
  * @priv: a pointer for the virtqueue implementation to use.
  */
 struct virtqueue {
@@ -22,60 +22,71 @@ struct virtqueue {
 	void (*callback)(struct virtqueue *vq);
 	const char *name;
 	struct virtio_device *vdev;
-	struct virtqueue_ops *vq_ops;
 	void *priv;
 };
 
 /**
- * virtqueue_ops - operations for virtqueue abstraction layer
- * @add_buf: expose buffer to other end
+ * operations for virtqueue
+ * virtqueue_add_buf: expose buffer to other end
  *	vq: the struct virtqueue we're talking about.
  *	sg: the description of the buffer(s).
  *	out_num: the number of sg readable by other side
  *	in_num: the number of sg which are writable (after readable ones)
  *	data: the token identifying the buffer.
+ *	gfp: how to do memory allocations (if necessary).
  *      Returns remaining capacity of queue (sg segments) or a negative error.
- * @kick: update after add_buf
+ * virtqueue_kick: update after add_buf
  *	vq: the struct virtqueue
  *	After one or more add_buf calls, invoke this to kick the other side.
- * @get_buf: get the next used buffer
+ * virtqueue_get_buf: get the next used buffer
  *	vq: the struct virtqueue we're talking about.
  *	len: the length written into the buffer
  *	Returns NULL or the "data" token handed to add_buf.
- * @disable_cb: disable callbacks
+ * virtqueue_disable_cb: disable callbacks
  *	vq: the struct virtqueue we're talking about.
  *	Note that this is not necessarily synchronous, hence unreliable and only
  *	useful as an optimization.
- * @enable_cb: restart callbacks after disable_cb.
+ * virtqueue_enable_cb: restart callbacks after disable_cb.
  *	vq: the struct virtqueue we're talking about.
  *	This re-enables callbacks; it returns "false" if there are pending
  *	buffers in the queue, to detect a possible race between the driver
  *	checking for more work, and enabling callbacks.
- * @detach_unused_buf: detach first unused buffer
+ * virtqueue_detach_unused_buf: detach first unused buffer
  * 	vq: the struct virtqueue we're talking about.
  * 	Returns NULL or the "data" token handed to add_buf
  *
  * Locking rules are straightforward: the driver is responsible for
  * locking.  No two operations may be invoked simultaneously, with the exception
- * of @disable_cb.
+ * of virtqueue_disable_cb.
  *
  * All operations can be called in any context.
  */
-struct virtqueue_ops {
-	int (*add_buf)(struct virtqueue *vq,
-		       struct scatterlist sg[],
-		       unsigned int out_num,
-		       unsigned int in_num,
-		       void *data);
 
-	void (*kick)(struct virtqueue *vq);
+int virtqueue_add_buf_gfp(struct virtqueue *vq,
+			  struct scatterlist sg[],
+			  unsigned int out_num,
+			  unsigned int in_num,
+			  void *data,
+			  gfp_t gfp);
 
-	void *(*get_buf)(struct virtqueue *vq, unsigned int *len);
+static inline int virtqueue_add_buf(struct virtqueue *vq,
+				    struct scatterlist sg[],
+				    unsigned int out_num,
+				    unsigned int in_num,
+				    void *data)
+{
+	return virtqueue_add_buf_gfp(vq, sg, out_num, in_num, data, GFP_ATOMIC);
+}
 
-	void (*disable_cb)(struct virtqueue *vq);
-	bool (*enable_cb)(struct virtqueue *vq);
-	void *(*detach_unused_buf)(struct virtqueue *vq);
-};
+void virtqueue_kick(struct virtqueue *vq);
+
+void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len);
+
+void virtqueue_disable_cb(struct virtqueue *vq);
+
+bool virtqueue_enable_cb(struct virtqueue *vq);
+
+void *virtqueue_detach_unused_buf(struct virtqueue *vq);
 
 /**
  * virtio_device - representation of a device using virtio

include/linux/virtio_blk.h

@@ -17,6 +17,8 @@
 #define VIRTIO_BLK_F_FLUSH	9	/* Cache flush command support */
 #define VIRTIO_BLK_F_TOPOLOGY	10	/* Topology information is available */
 
+#define VIRTIO_BLK_ID_BYTES	20	/* ID string length */
+
 struct virtio_blk_config {
 	/* The capacity (in 512-byte sectors). */
 	__u64 capacity;
@@ -67,6 +69,9 @@ struct virtio_blk_config {
 /* Cache flush command */
 #define VIRTIO_BLK_T_FLUSH	4
 
+/* Get device ID command */
+#define VIRTIO_BLK_T_GET_ID    8
+
 /* Barrier before this op. */
 #define VIRTIO_BLK_T_BARRIER	0x80000000
 

include/linux/virtio_console.h

@@ -12,14 +12,39 @@
 
 /* Feature bits */
 #define VIRTIO_CONSOLE_F_SIZE	0	/* Does host provide console size? */
+#define VIRTIO_CONSOLE_F_MULTIPORT 1	/* Does host provide multiple ports? */
+
+#define VIRTIO_CONSOLE_BAD_ID		(~(u32)0)
 
 struct virtio_console_config {
 	/* colums of the screens */
 	__u16 cols;
 	/* rows of the screens */
 	__u16 rows;
+	/* max. number of ports this device can hold */
+	__u32 max_nr_ports;
 } __attribute__((packed));
 
+/*
+ * A message that's passed between the Host and the Guest for a
+ * particular port.
+ */
+struct virtio_console_control {
+	__u32 id;		/* Port number */
+	__u16 event;		/* The kind of control event (see below) */
+	__u16 value;		/* Extra information for the key */
+};
+
+/* Some events for control messages */
+#define VIRTIO_CONSOLE_DEVICE_READY	0
+#define VIRTIO_CONSOLE_PORT_ADD		1
+#define VIRTIO_CONSOLE_PORT_REMOVE	2
+#define VIRTIO_CONSOLE_PORT_READY	3
+#define VIRTIO_CONSOLE_CONSOLE_PORT	4
+#define VIRTIO_CONSOLE_RESIZE		5
+#define VIRTIO_CONSOLE_PORT_OPEN	6
+#define VIRTIO_CONSOLE_PORT_NAME	7
+
 #ifdef __KERNEL__
 int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int));
 #endif /* __KERNEL__ */

net/9p/trans_virtio.c

@@ -137,7 +137,7 @@ static void req_done(struct virtqueue *vq)
 
 	P9_DPRINTK(P9_DEBUG_TRANS, ": request done\n");
 
-	while ((rc = chan->vq->vq_ops->get_buf(chan->vq, &len)) != NULL) {
+	while ((rc = virtqueue_get_buf(chan->vq, &len)) != NULL) {
 		P9_DPRINTK(P9_DEBUG_TRANS, ": rc %p\n", rc);
 		P9_DPRINTK(P9_DEBUG_TRANS, ": lookup tag %d\n", rc->tag);
 		req = p9_tag_lookup(chan->client, rc->tag);
@@ -209,13 +209,13 @@ p9_virtio_request(struct p9_client *client, struct p9_req_t *req)
 
 	req->status = REQ_STATUS_SENT;
 
-	if (chan->vq->vq_ops->add_buf(chan->vq, chan->sg, out, in, req->tc) < 0) {
+	if (virtqueue_add_buf(chan->vq, chan->sg, out, in, req->tc) < 0) {
 		P9_DPRINTK(P9_DEBUG_TRANS,
 			"9p debug: virtio rpc add_buf returned failure");
 		return -EIO;
 	}
 
-	chan->vq->vq_ops->kick(chan->vq);
+	virtqueue_kick(chan->vq);
 
 	P9_DPRINTK(P9_DEBUG_TRANS, "9p debug: virtio request kicked\n");
 	return 0;