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virtio: move queue_index and num_free fields into core struct virtqueue.
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They're generic concepts, so hoist them.  This also avoids accessor
functions (though kept around for merge with DaveM's net tree).

This goes even further than Jason Wang's 17bb6d4 patch
("virtio-ring: move queue_index to vring_virtqueue") which moved the
queue_index from the specific transport.

Acked-by: Michael S. Tsirkin <[email protected]>
Signed-off-by: Rusty Russell <[email protected]>
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@rustyrussell
rustyrussell committed Dec 18, 2012
1 parent 1ce6853 commit 06ca287
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Showing 4 changed files with 28 additions and 30 deletions.
4 changes: 2 additions & 2 deletions drivers/virtio/virtio_mmio.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -225,7 +225,7 @@ static void vm_notify(struct virtqueue *vq)

/* We write the queue's selector into the notification register to
* signal the other end */
writel(virtqueue_get_queue_index(vq), vm_dev->base + VIRTIO_MMIO_QUEUE_NOTIFY);
writel(vq->index, vm_dev->base + VIRTIO_MMIO_QUEUE_NOTIFY);
}

/* Notify all virtqueues on an interrupt. */
Expand Down Expand Up @@ -266,7 +266,7 @@ static void vm_del_vq(struct virtqueue *vq)
struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev);
struct virtio_mmio_vq_info *info = vq->priv;
unsigned long flags, size;
unsigned int index = virtqueue_get_queue_index(vq);
unsigned int index = vq->index;

spin_lock_irqsave(&vm_dev->lock, flags);
list_del(&info->node);
Expand Down
6 changes: 2 additions & 4 deletions drivers/virtio/virtio_pci.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -203,8 +203,7 @@ static void vp_notify(struct virtqueue *vq)

/* we write the queue's selector into the notification register to
* signal the other end */
iowrite16(virtqueue_get_queue_index(vq),
vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
}

/* Handle a configuration change: Tell driver if it wants to know. */
Expand Down Expand Up @@ -479,8 +478,7 @@ static void vp_del_vq(struct virtqueue *vq)
list_del(&info->node);
spin_unlock_irqrestore(&vp_dev->lock, flags);

iowrite16(virtqueue_get_queue_index(vq),
vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);

if (vp_dev->msix_enabled) {
iowrite16(VIRTIO_MSI_NO_VECTOR,
Expand Down
34 changes: 11 additions & 23 deletions drivers/virtio/virtio_ring.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -93,8 +93,6 @@ struct vring_virtqueue
/* Host publishes avail event idx */
bool event;

/* Number of free buffers */
unsigned int num_free;
/* Head of free buffer list. */
unsigned int free_head;
/* Number we've added since last sync. */
Expand All @@ -106,9 +104,6 @@ struct vring_virtqueue
/* How to notify other side. FIXME: commonalize hcalls! */
void (*notify)(struct virtqueue *vq);

/* Index of the queue */
int queue_index;

#ifdef DEBUG
/* They're supposed to lock for us. */
unsigned int in_use;
Expand Down Expand Up @@ -167,7 +162,7 @@ static int vring_add_indirect(struct vring_virtqueue *vq,
desc[i-1].next = 0;

/* We're about to use a buffer */
vq->num_free--;
vq->vq.num_free--;

/* Use a single buffer which doesn't continue */
head = vq->free_head;
Expand All @@ -181,13 +176,6 @@ static int vring_add_indirect(struct vring_virtqueue *vq,
return head;
}

int virtqueue_get_queue_index(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
return vq->queue_index;
}
EXPORT_SYMBOL_GPL(virtqueue_get_queue_index);

/**
* virtqueue_add_buf - expose buffer to other end
* @vq: the struct virtqueue we're talking about.
Expand Down Expand Up @@ -235,7 +223,7 @@ int virtqueue_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) {
if (vq->indirect && (out + in) > 1 && vq->vq.num_free) {
head = vring_add_indirect(vq, sg, out, in, gfp);
if (likely(head >= 0))
goto add_head;
Expand All @@ -244,9 +232,9 @@ int virtqueue_add_buf(struct virtqueue *_vq,
BUG_ON(out + in > vq->vring.num);
BUG_ON(out + in == 0);

if (vq->num_free < out + in) {
if (vq->vq.num_free < out + in) {
pr_debug("Can't add buf len %i - avail = %i\n",
out + in, vq->num_free);
out + in, vq->vq.num_free);
/* FIXME: for historical reasons, we force a notify here if
* there are outgoing parts to the buffer. Presumably the
* host should service the ring ASAP. */
Expand All @@ -257,7 +245,7 @@ int virtqueue_add_buf(struct virtqueue *_vq,
}

/* We're about to use some buffers from the free list. */
vq->num_free -= out + in;
vq->vq.num_free -= out + in;

head = vq->free_head;
for (i = vq->free_head; out; i = vq->vring.desc[i].next, out--) {
Expand Down Expand Up @@ -303,7 +291,7 @@ int virtqueue_add_buf(struct virtqueue *_vq,
pr_debug("Added buffer head %i to %p\n", head, vq);
END_USE(vq);

return vq->num_free;
return vq->vq.num_free;
}
EXPORT_SYMBOL_GPL(virtqueue_add_buf);

Expand Down Expand Up @@ -400,13 +388,13 @@ static void detach_buf(struct vring_virtqueue *vq, unsigned int head)

while (vq->vring.desc[i].flags & VRING_DESC_F_NEXT) {
i = vq->vring.desc[i].next;
vq->num_free++;
vq->vq.num_free++;
}

vq->vring.desc[i].next = vq->free_head;
vq->free_head = head;
/* Plus final descriptor */
vq->num_free++;
vq->vq.num_free++;
}

static inline bool more_used(const struct vring_virtqueue *vq)
Expand Down Expand Up @@ -606,7 +594,7 @@ void *virtqueue_detach_unused_buf(struct virtqueue *_vq)
return buf;
}
/* That should have freed everything. */
BUG_ON(vq->num_free != vq->vring.num);
BUG_ON(vq->vq.num_free != vq->vring.num);

END_USE(vq);
return NULL;
Expand Down Expand Up @@ -660,12 +648,13 @@ struct virtqueue *vring_new_virtqueue(unsigned int index,
vq->vq.callback = callback;
vq->vq.vdev = vdev;
vq->vq.name = name;
vq->vq.num_free = num;
vq->vq.index = index;
vq->notify = notify;
vq->weak_barriers = weak_barriers;
vq->broken = false;
vq->last_used_idx = 0;
vq->num_added = 0;
vq->queue_index = index;
list_add_tail(&vq->vq.list, &vdev->vqs);
#ifdef DEBUG
vq->in_use = false;
Expand All @@ -680,7 +669,6 @@ struct virtqueue *vring_new_virtqueue(unsigned int index,
vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;

/* Put everything in free lists. */
vq->num_free = num;
vq->free_head = 0;
for (i = 0; i < num-1; i++) {
vq->vring.desc[i].next = i+1;
Expand Down
14 changes: 13 additions & 1 deletion include/linux/virtio.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -16,12 +16,20 @@
* @name: the name of this virtqueue (mainly for debugging)
* @vdev: the virtio device this queue was created for.
* @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.
*
* A note on @num_free: with indirect buffers, each buffer needs one
* element in the queue, otherwise a buffer will need one element per
* sg element.
*/
struct virtqueue {
struct list_head list;
void (*callback)(struct virtqueue *vq);
const char *name;
struct virtio_device *vdev;
unsigned int index;
unsigned int num_free;
void *priv;
};

Expand Down Expand Up @@ -50,7 +58,11 @@ void *virtqueue_detach_unused_buf(struct virtqueue *vq);

unsigned int virtqueue_get_vring_size(struct virtqueue *vq);

int virtqueue_get_queue_index(struct virtqueue *vq);
/* FIXME: Obsolete accessor, but required for virtio_net merge. */
static inline unsigned int virtqueue_get_queue_index(struct virtqueue *vq)
{
return vq->index;
}

/**
* virtio_device - representation of a device using virtio
Expand Down

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