1 files changed, 59 insertions, 30 deletions

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 41144b5246a8..c5310eaf8b46 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -231,10 +231,10 @@ static void vring_free(struct virtqueue *_vq);
  * Helpers.
  */
 
-#define to_vvq(_vq) container_of(_vq, struct vring_virtqueue, vq)
+#define to_vvq(_vq) container_of_const(_vq, struct vring_virtqueue, vq)
 
-static inline bool virtqueue_use_indirect(struct vring_virtqueue *vq,
-					  unsigned int total_sg)
+static bool virtqueue_use_indirect(const struct vring_virtqueue *vq,
+				   unsigned int total_sg)
 {
 	/*
 	 * If the host supports indirect descriptor tables, and we have multiple
@@ -269,7 +269,7 @@ static inline bool virtqueue_use_indirect(struct vring_virtqueue *vq,
  * unconditionally on data path.
  */
 
-static bool vring_use_dma_api(struct virtio_device *vdev)
+static bool vring_use_dma_api(const struct virtio_device *vdev)
 {
 	if (!virtio_has_dma_quirk(vdev))
 		return true;
@@ -289,7 +289,7 @@ static bool vring_use_dma_api(struct virtio_device *vdev)
 	return false;
 }
 
-size_t virtio_max_dma_size(struct virtio_device *vdev)
+size_t virtio_max_dma_size(const struct virtio_device *vdev)
 {
 	size_t max_segment_size = SIZE_MAX;
 
@@ -349,7 +349,7 @@ static void vring_free_queue(struct virtio_device *vdev, size_t size,
  * making all of the arch DMA ops work on the vring device itself
  * is a mess.
  */
-static inline struct device *vring_dma_dev(const struct vring_virtqueue *vq)
+static struct device *vring_dma_dev(const struct vring_virtqueue *vq)
 {
 	return vq->dma_dev;
 }
@@ -423,7 +423,7 @@ static void virtqueue_init(struct vring_virtqueue *vq, u32 num)
  */
 
 static void vring_unmap_one_split_indirect(const struct vring_virtqueue *vq,
-					   struct vring_desc *desc)
+					   const struct vring_desc *desc)
 {
 	u16 flags;
 
@@ -784,7 +784,7 @@ static void detach_buf_split(struct vring_virtqueue *vq, unsigned int head,
 	}
 }
 
-static inline bool more_used_split(const struct vring_virtqueue *vq)
+static bool more_used_split(const struct vring_virtqueue *vq)
 {
 	return vq->last_used_idx != virtio16_to_cpu(vq->vq.vdev,
 			vq->split.vring.used->idx);
@@ -854,6 +854,14 @@ static void virtqueue_disable_cb_split(struct virtqueue *_vq)
 
 	if (!(vq->split.avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT)) {
 		vq->split.avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT;
+
+		/*
+		 * If device triggered an event already it won't trigger one again:
+		 * no need to disable.
+		 */
+		if (vq->event_triggered)
+			return;
+
 		if (vq->event)
 			/* TODO: this is a hack. Figure out a cleaner value to write. */
 			vring_used_event(&vq->split.vring) = 0x0;
@@ -1172,18 +1180,18 @@ err:
 /*
  * Packed ring specific functions - *_packed().
  */
-static inline bool packed_used_wrap_counter(u16 last_used_idx)
+static bool packed_used_wrap_counter(u16 last_used_idx)
 {
 	return !!(last_used_idx & (1 << VRING_PACKED_EVENT_F_WRAP_CTR));
 }
 
-static inline u16 packed_last_used(u16 last_used_idx)
+static u16 packed_last_used(u16 last_used_idx)
 {
 	return last_used_idx & ~(-(1 << VRING_PACKED_EVENT_F_WRAP_CTR));
 }
 
 static void vring_unmap_extra_packed(const struct vring_virtqueue *vq,
-				     struct vring_desc_extra *extra)
+				     const struct vring_desc_extra *extra)
 {
 	u16 flags;
 
@@ -1206,7 +1214,7 @@ static void vring_unmap_extra_packed(const struct vring_virtqueue *vq,
 }
 
 static void vring_unmap_desc_packed(const struct vring_virtqueue *vq,
-				   struct vring_packed_desc *desc)
+				    const struct vring_packed_desc *desc)
 {
 	u16 flags;
 
@@ -1612,7 +1620,7 @@ static inline bool is_used_desc_packed(const struct vring_virtqueue *vq,
 	return avail == used && used == used_wrap_counter;
 }
 
-static inline bool more_used_packed(const struct vring_virtqueue *vq)
+static bool more_used_packed(const struct vring_virtqueue *vq)
 {
 	u16 last_used;
 	u16 last_used_idx;
@@ -1699,6 +1707,14 @@ static void virtqueue_disable_cb_packed(struct virtqueue *_vq)
 
 	if (vq->packed.event_flags_shadow != VRING_PACKED_EVENT_FLAG_DISABLE) {
 		vq->packed.event_flags_shadow = VRING_PACKED_EVENT_FLAG_DISABLE;
+
+		/*
+		 * If device triggered an event already it won't trigger one again:
+		 * no need to disable.
+		 */
+		if (vq->event_triggered)
+			return;
+
 		vq->packed.vring.driver->flags =
 			cpu_to_le16(vq->packed.event_flags_shadow);
 	}
@@ -2330,12 +2346,6 @@ void virtqueue_disable_cb(struct virtqueue *_vq)
 {
 	struct vring_virtqueue *vq = to_vvq(_vq);
 
-	/* If device triggered an event already it won't trigger one again:
-	 * no need to disable.
-	 */
-	if (vq->event_triggered)
-		return;
-
 	if (vq->packed_ring)
 		virtqueue_disable_cb_packed(_vq);
 	else
@@ -2752,6 +2762,23 @@ void vring_del_virtqueue(struct virtqueue *_vq)
 }
 EXPORT_SYMBOL_GPL(vring_del_virtqueue);
 
+u32 vring_notification_data(struct virtqueue *_vq)
+{
+	struct vring_virtqueue *vq = to_vvq(_vq);
+	u16 next;
+
+	if (vq->packed_ring)
+		next = (vq->packed.next_avail_idx &
+				~(-(1 << VRING_PACKED_EVENT_F_WRAP_CTR))) |
+			vq->packed.avail_wrap_counter <<
+				VRING_PACKED_EVENT_F_WRAP_CTR;
+	else
+		next = vq->split.avail_idx_shadow;
+
+	return next << 16 | _vq->index;
+}
+EXPORT_SYMBOL_GPL(vring_notification_data);
+
 /* Manipulates transport-specific feature bits. */
 void vring_transport_features(struct virtio_device *vdev)
 {
@@ -2771,6 +2798,8 @@ void vring_transport_features(struct virtio_device *vdev)
 			break;
 		case VIRTIO_F_ORDER_PLATFORM:
 			break;
+		case VIRTIO_F_NOTIFICATION_DATA:
+			break;
 		default:
 			/* We don't understand this bit. */
 			__virtio_clear_bit(vdev, i);
@@ -2786,10 +2815,10 @@ EXPORT_SYMBOL_GPL(vring_transport_features);
  * Returns the size of the vring.  This is mainly used for boasting to
  * userspace.  Unlike other operations, this need not be serialized.
  */
-unsigned int virtqueue_get_vring_size(struct virtqueue *_vq)
+unsigned int virtqueue_get_vring_size(const struct virtqueue *_vq)
 {
 
-	struct vring_virtqueue *vq = to_vvq(_vq);
+	const struct vring_virtqueue *vq = to_vvq(_vq);
 
 	return vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num;
 }
@@ -2819,9 +2848,9 @@ void __virtqueue_unbreak(struct virtqueue *_vq)
 }
 EXPORT_SYMBOL_GPL(__virtqueue_unbreak);
 
-bool virtqueue_is_broken(struct virtqueue *_vq)
+bool virtqueue_is_broken(const struct virtqueue *_vq)
 {
-	struct vring_virtqueue *vq = to_vvq(_vq);
+	const struct vring_virtqueue *vq = to_vvq(_vq);
 
 	return READ_ONCE(vq->broken);
 }
@@ -2868,9 +2897,9 @@ void __virtio_unbreak_device(struct virtio_device *dev)
 }
 EXPORT_SYMBOL_GPL(__virtio_unbreak_device);
 
-dma_addr_t virtqueue_get_desc_addr(struct virtqueue *_vq)
+dma_addr_t virtqueue_get_desc_addr(const struct virtqueue *_vq)
 {
-	struct vring_virtqueue *vq = to_vvq(_vq);
+	const struct vring_virtqueue *vq = to_vvq(_vq);
 
 	BUG_ON(!vq->we_own_ring);
 
@@ -2881,9 +2910,9 @@ dma_addr_t virtqueue_get_desc_addr(struct virtqueue *_vq)
 }
 EXPORT_SYMBOL_GPL(virtqueue_get_desc_addr);
 
-dma_addr_t virtqueue_get_avail_addr(struct virtqueue *_vq)
+dma_addr_t virtqueue_get_avail_addr(const struct virtqueue *_vq)
 {
-	struct vring_virtqueue *vq = to_vvq(_vq);
+	const struct vring_virtqueue *vq = to_vvq(_vq);
 
 	BUG_ON(!vq->we_own_ring);
 
@@ -2895,9 +2924,9 @@ dma_addr_t virtqueue_get_avail_addr(struct virtqueue *_vq)
 }
 EXPORT_SYMBOL_GPL(virtqueue_get_avail_addr);
 
-dma_addr_t virtqueue_get_used_addr(struct virtqueue *_vq)
+dma_addr_t virtqueue_get_used_addr(const struct virtqueue *_vq)
 {
-	struct vring_virtqueue *vq = to_vvq(_vq);
+	const struct vring_virtqueue *vq = to_vvq(_vq);
 
 	BUG_ON(!vq->we_own_ring);
 
@@ -2910,7 +2939,7 @@ dma_addr_t virtqueue_get_used_addr(struct virtqueue *_vq)
 EXPORT_SYMBOL_GPL(virtqueue_get_used_addr);
 
 /* Only available for split ring */
-const struct vring *virtqueue_get_vring(struct virtqueue *vq)
+const struct vring *virtqueue_get_vring(const struct virtqueue *vq)
 {
 	return &to_vvq(vq)->split.vring;
 }