virtio: Use const pointer for vu_dev

We don't modify the structure in some virtio functions.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

4 files changed, 12 insertions, 8 deletions

diff --git a/virtio.c b/virtio.c
index a76de5e..625bac3 100644
--- a/virtio.c
+++ b/virtio.c
@@ -92,7 +92,8 @@
  *
  * Return: virtual address in our address space of the guest physical address
  */
-static void *vu_gpa_to_va(struct vu_dev *dev, uint64_t *plen, uint64_t guest_addr)
+static void *vu_gpa_to_va(const struct vu_dev *dev, uint64_t *plen,
+			  uint64_t guest_addr)
 {
 	unsigned int i;
 
@@ -210,7 +211,8 @@ static void virtqueue_get_head(const struct vu_virtq *vq,
  *
  * Return: -1 if there is an error, 0 otherwise
  */
-static int virtqueue_read_indirect_desc(struct vu_dev *dev, struct vring_desc *desc,
+static int virtqueue_read_indirect_desc(const struct vu_dev *dev,
+					struct vring_desc *desc,
 					uint64_t addr, size_t len)
 {
 	uint64_t read_len;
@@ -390,7 +392,7 @@ static inline void vring_set_avail_event(const struct vu_virtq *vq,
  *
  * Return: false on error, true otherwise
  */
-static bool virtqueue_map_desc(struct vu_dev *dev,
+static bool virtqueue_map_desc(const struct vu_dev *dev,
 			       unsigned int *p_num_sg, struct iovec *iov,
 			       unsigned int max_num_sg,
 			       uint64_t pa, size_t sz)
@@ -426,7 +428,8 @@ static bool virtqueue_map_desc(struct vu_dev *dev,
  *
  * Return: -1 if there is an error, 0 otherwise
  */
-static int vu_queue_map_desc(struct vu_dev *dev, struct vu_virtq *vq, unsigned int idx,
+static int vu_queue_map_desc(const struct vu_dev *dev,
+			     struct vu_virtq *vq, unsigned int idx,
 			     struct vu_virtq_element *elem)
 {
 	const struct vring_desc *desc = vq->vring.desc;
@@ -504,7 +507,8 @@ static int vu_queue_map_desc(struct vu_dev *dev, struct vu_virtq *vq, unsigned i
  *
  * Return: -1 if there is an error, 0 otherwise
  */
-int vu_queue_pop(struct vu_dev *dev, struct vu_virtq *vq, struct vu_virtq_element *elem)
+int vu_queue_pop(const struct vu_dev *dev, struct vu_virtq *vq,
+		 struct vu_virtq_element *elem)
 {
 	unsigned int head;
 	int ret;
diff --git a/virtio.h b/virtio.h
index 6410d60..0af259d 100644
--- a/virtio.h
+++ b/virtio.h
@@ -170,7 +170,7 @@ static inline bool vu_has_protocol_feature(const struct vu_dev *vdev,
 
 bool vu_queue_empty(struct vu_virtq *vq);
 void vu_queue_notify(const struct vu_dev *dev, struct vu_virtq *vq);
-int vu_queue_pop(struct vu_dev *dev, struct vu_virtq *vq,
+int vu_queue_pop(const struct vu_dev *dev, struct vu_virtq *vq,
 		 struct vu_virtq_element *elem);
 void vu_queue_detach_element(struct vu_virtq *vq);
 void vu_queue_unpop(struct vu_virtq *vq);
diff --git a/vu_common.c b/vu_common.c
index 299b5a3..6d365be 100644
--- a/vu_common.c
+++ b/vu_common.c
@@ -73,7 +73,7 @@ void vu_init_elem(struct vu_virtq_element *elem, struct iovec *iov, int elem_cnt
  *
  * Return: number of elements used to contain the frame
  */
-int vu_collect(struct vu_dev *vdev, struct vu_virtq *vq,
+int vu_collect(const struct vu_dev *vdev, struct vu_virtq *vq,
 	       struct vu_virtq_element *elem, int max_elem,
 	       size_t size, size_t *frame_size)
 {
diff --git a/vu_common.h b/vu_common.h
index 901d972..bd70faf 100644
--- a/vu_common.h
+++ b/vu_common.h
@@ -46,7 +46,7 @@ static inline void vu_set_element(struct vu_virtq_element *elem,
 
 void vu_init_elem(struct vu_virtq_element *elem, struct iovec *iov,
 		  int elem_cnt);
-int vu_collect(struct vu_dev *vdev, struct vu_virtq *vq,
+int vu_collect(const struct vu_dev *vdev, struct vu_virtq *vq,
 	       struct vu_virtq_element *elem, int max_elem, size_t size,
 	       size_t *frame_size);
 void vu_set_vnethdr(const struct vu_dev *vdev,