virtio: add names to virtqueue struct, mapping from devices to queues.

Add a linked list of all virtqueues for a virtio device: this helps for
debugging and is also needed for upcoming interface change.

Also, add a "name" field for clearer debug messages.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

4 files changed, 27 insertions, 11 deletions

diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 6b6810364860..3f52c767dfe9 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -186,6 +186,8 @@ int register_virtio_device(struct virtio_device *dev)
         /* Acknowledge that we've seen the device. */
         add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
 
+        INIT_LIST_HEAD(&dev->vqs);
+
         /* device_register() causes the bus infrastructure to look for a
          * matching driver. */
         err = device_register(&dev->dev);
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 9c76a061a04d..0fa73b4d18b0 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -218,13 +218,13 @@ static int virtballoon_probe(struct virtio_device *vdev)
         vb->vdev = vdev;
 
         /* We expect two virtqueues. */
-        vb->inflate_vq = vdev->config->find_vq(vdev, 0, balloon_ack);
+        vb->inflate_vq = vdev->config->find_vq(vdev, 0, balloon_ack, "inflate");
         if (IS_ERR(vb->inflate_vq)) {
                 err = PTR_ERR(vb->inflate_vq);
                 goto out_free_vb;
         }
 
-        vb->deflate_vq = vdev->config->find_vq(vdev, 1, balloon_ack);
+        vb->deflate_vq = vdev->config->find_vq(vdev, 1, balloon_ack, "deflate");
         if (IS_ERR(vb->deflate_vq)) {
                 err = PTR_ERR(vb->deflate_vq);
                 goto out_del_inflate_vq;
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index 330aacbdec1f..be4047abd5ba 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -208,7 +208,8 @@ static irqreturn_t vp_interrupt(int irq, void *opaque)
 
 /* the config->find_vq() implementation */
 static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
-                                    void (*callback)(struct virtqueue *vq))
+                                    void (*callback)(struct virtqueue *vq),
+                                    const char *name)
 {
         struct virtio_pci_device *vp_dev = to_vp_device(vdev);
         struct virtio_pci_vq_info *info;
@@ -247,7 +248,7 @@ static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
 
         /* create the vring */
         vq = vring_new_virtqueue(info->num, VIRTIO_PCI_VRING_ALIGN,
-                                 vdev, info->queue, vp_notify, callback);
+                                 vdev, info->queue, vp_notify, callback, name);
         if (!vq) {
                 err = -ENOMEM;
                 goto out_activate_queue;
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 5c52369ab9bb..579fa693d5d0 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -23,21 +23,30 @@
 
 #ifdef DEBUG
 /* For development, we want to crash whenever the ring is screwed. */
-#define BAD_RING(_vq, fmt...)                   \
-        do { dev_err(&(_vq)->vq.vdev->dev, fmt); BUG(); } while(0)
+#define BAD_RING(_vq, fmt, args...)                             \
+        do {                                                    \
+                dev_err(&(_vq)->vq.vdev->dev,                   \
+                        "%s:"fmt, (_vq)->vq.name, ##args);      \
+                BUG();                                          \
+        } while (0)
 /* Caller is supposed to guarantee no reentry. */
 #define START_USE(_vq)                                          \
         do {                                                    \
                 if ((_vq)->in_use)                              \
-                        panic("in_use = %i\n", (_vq)->in_use);  \
+                        panic("%s:in_use = %i\n",               \
+                              (_vq)->vq.name, (_vq)->in_use);   \
                 (_vq)->in_use = __LINE__;                       \
                 mb();                                           \
-        } while(0)
+        } while (0)
 #define END_USE(_vq) \
         do { BUG_ON(!(_vq)->in_use); (_vq)->in_use = 0; mb(); } while(0)
 #else
-#define BAD_RING(_vq, fmt...)                   \
-        do { dev_err(&_vq->vq.vdev->dev, fmt); (_vq)->broken = true; } while(0)
+#define BAD_RING(_vq, fmt, args...)                             \
+        do {                                                    \
+                dev_err(&_vq->vq.vdev->dev,                     \
+                        "%s:"fmt, (_vq)->vq.name, ##args);      \
+                (_vq)->broken = true;                           \
+        } while (0)
 #define START_USE(vq)
 #define END_USE(vq)
 #endif
@@ -284,7 +293,8 @@ struct virtqueue *vring_new_virtqueue(unsigned int num,
                                       struct virtio_device *vdev,
                                       void *pages,
                                       void (*notify)(struct virtqueue *),
-                                      void (*callback)(struct virtqueue *))
+                                      void (*callback)(struct virtqueue *),
+                                      const char *name)
 {
         struct vring_virtqueue *vq;
         unsigned int i;
@@ -303,10 +313,12 @@ struct virtqueue *vring_new_virtqueue(unsigned int num,
         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;
         vq->last_used_idx = 0;
         vq->num_added = 0;
+        list_add_tail(&vq->vq.list, &vdev->vqs);
 #ifdef DEBUG
         vq->in_use = false;
 #endif
@@ -327,6 +339,7 @@ EXPORT_SYMBOL_GPL(vring_new_virtqueue);
 
 void vring_del_virtqueue(struct virtqueue *vq)
 {
+        list_del(&vq->list);
         kfree(to_vvq(vq));
 }
 EXPORT_SYMBOL_GPL(vring_del_virtqueue);