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path: root/drivers/virtio/virtio_ring.c
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Diffstat (limited to 'drivers/virtio/virtio_ring.c')
-rw-r--r--drivers/virtio/virtio_ring.c46
1 files changed, 19 insertions, 27 deletions
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index e639584..ffd7e7d 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -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. */
@@ -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;
@@ -135,6 +130,13 @@ static int vring_add_indirect(struct vring_virtqueue *vq,
unsigned head;
int i;
+ /*
+ * We require lowmem mappings for the descriptors because
+ * otherwise virt_to_phys will give us bogus addresses in the
+ * virtqueue.
+ */
+ gfp &= ~(__GFP_HIGHMEM | __GFP_HIGH);
+
desc = kmalloc((out + in) * sizeof(struct vring_desc), gfp);
if (!desc)
return -ENOMEM;
@@ -160,7 +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;
@@ -174,13 +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.
@@ -193,10 +188,7 @@ EXPORT_SYMBOL_GPL(virtqueue_get_queue_index);
* Caller must ensure we don't call this with other virtqueue operations
* at the same time (except where noted).
*
- * Returns remaining capacity of queue or a negative error
- * (ie. ENOSPC). Note that it only really makes sense to treat all
- * positive return values as "available": indirect buffers mean that
- * we can put an entire sg[] array inside a single queue entry.
+ * Returns zero or a negative error (ie. ENOSPC, ENOMEM).
*/
int virtqueue_add_buf(struct virtqueue *_vq,
struct scatterlist sg[],
@@ -228,7 +220,7 @@ 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;
@@ -237,9 +229,9 @@ 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. */
@@ -250,7 +242,7 @@ 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--) {
@@ -296,7 +288,7 @@ add_head:
pr_debug("Added buffer head %i to %p\n", head, vq);
END_USE(vq);
- return vq->num_free;
+ return 0;
}
EXPORT_SYMBOL_GPL(virtqueue_add_buf);
@@ -393,13 +385,13 @@ 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)
@@ -599,7 +591,7 @@ 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;
@@ -653,12 +645,13 @@ 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;
@@ -673,7 +666,6 @@ 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;