virtio: find_vqs() add arg sizes

find_vqs() adds a new parameter sizes to specify the size of each vq
vring.

NULL as sizes means that all queues in find_vqs() use the maximum size.
A value in the array is 0, which means that the corresponding queue uses
the maximum size.

In the split scenario, the meaning of size is the largest size, because
it may be limited by memory, the virtio core will try a smaller size.
And the size is power of 2.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220801063902.129329-34-xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

arch/um/drivers/virtio_uml.c

@@ -1011,7 +1011,7 @@ static struct virtqueue *vu_setup_vq(struct virtio_device *vdev,
 
 static int vu_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 		       struct virtqueue *vqs[], vq_callback_t *callbacks[],
-		       const char * const names[], const bool *ctx,
+		       const char * const names[], u32 sizes[], const bool *ctx,
 		       struct irq_affinity *desc)
 {
 	struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev);

drivers/platform/mellanox/mlxbf-tmfifo.c

@@ -928,6 +928,7 @@ static int mlxbf_tmfifo_virtio_find_vqs(struct virtio_device *vdev,
 					struct virtqueue *vqs[],
 					vq_callback_t *callbacks[],
 					const char * const names[],
+					u32 sizes[],
 					const bool *ctx,
 					struct irq_affinity *desc)
 {

drivers/remoteproc/remoteproc_virtio.c

@@ -158,6 +158,7 @@ static int rproc_virtio_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
 				 struct virtqueue *vqs[],
 				 vq_callback_t *callbacks[],
 				 const char * const names[],
+				 u32 sizes[],
 				 const bool * ctx,
 				 struct irq_affinity *desc)
 {

drivers/s390/virtio/virtio_ccw.c

@@ -635,6 +635,7 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 			       struct virtqueue *vqs[],
 			       vq_callback_t *callbacks[],
 			       const char * const names[],
+			       u32 sizes[],
 			       const bool *ctx,
 			       struct irq_affinity *desc)
 {

drivers/virtio/virtio_mmio.c

@@ -474,6 +474,7 @@ static int vm_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
 		       struct virtqueue *vqs[],
 		       vq_callback_t *callbacks[],
 		       const char * const names[],
+		       u32 sizes[],
 		       const bool *ctx,
 		       struct irq_affinity *desc)
 {

drivers/virtio/virtio_pci_common.c

@@ -396,7 +396,7 @@ static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned int nvqs,
 /* the config->find_vqs() implementation */
 int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
 		struct virtqueue *vqs[], vq_callback_t *callbacks[],
-		const char * const names[], const bool *ctx,
+		const char * const names[], u32 sizes[], const bool *ctx,
 		struct irq_affinity *desc)
 {
 	int err;

drivers/virtio/virtio_pci_common.h

@@ -110,7 +110,7 @@ void vp_del_vqs(struct virtio_device *vdev);
 /* the config->find_vqs() implementation */
 int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
 		struct virtqueue *vqs[], vq_callback_t *callbacks[],
-		const char * const names[], const bool *ctx,
+		const char * const names[], u32 sizes[], const bool *ctx,
 		struct irq_affinity *desc);
 const char *vp_bus_name(struct virtio_device *vdev);
 

drivers/virtio/virtio_pci_modern.c

@@ -347,12 +347,15 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
 static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
 			      struct virtqueue *vqs[],
 			      vq_callback_t *callbacks[],
-			      const char * const names[], const bool *ctx,
+			      const char * const names[],
+			      u32 sizes[],
+			      const bool *ctx,
 			      struct irq_affinity *desc)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 	struct virtqueue *vq;
-	int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, ctx, desc);
+	int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, sizes, ctx,
+			     desc);
 
 	if (rc)
 		return rc;

drivers/virtio/virtio_vdpa.c

@@ -269,6 +269,7 @@ static int virtio_vdpa_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
 				struct virtqueue *vqs[],
 				vq_callback_t *callbacks[],
 				const char * const names[],
+				u32 sizes[],
 				const bool *ctx,
 				struct irq_affinity *desc)
 {

include/linux/virtio_config.h

@@ -55,6 +55,7 @@ struct virtio_shm_region {
  *		include a NULL entry for vqs that do not need a callback
  *	names: array of virtqueue names (mainly for debugging)
  *		include a NULL entry for vqs unused by driver
+ *	sizes: array of virtqueue sizes
  *	Returns 0 on success or error status
  * @del_vqs: free virtqueues found by find_vqs().
  * @synchronize_cbs: synchronize with the virtqueue callbacks (optional)
@@ -103,7 +104,9 @@ struct virtio_config_ops {
 	void (*reset)(struct virtio_device *vdev);
 	int (*find_vqs)(struct virtio_device *, unsigned nvqs,
 			struct virtqueue *vqs[], vq_callback_t *callbacks[],
-			const char * const names[], const bool *ctx,
+			const char * const names[],
+			u32 sizes[],
+			const bool *ctx,
 			struct irq_affinity *desc);
 	void (*del_vqs)(struct virtio_device *);
 	void (*synchronize_cbs)(struct virtio_device *);
@@ -212,7 +215,7 @@ struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev,
 	const char *names[] = { n };
 	struct virtqueue *vq;
 	int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names, NULL,
-					 NULL);
+					 NULL, NULL);
 	if (err < 0)
 		return ERR_PTR(err);
 	return vq;
@@ -224,7 +227,8 @@ int virtio_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 			const char * const names[],
 			struct irq_affinity *desc)
 {
-	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, NULL, desc);
+	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, NULL,
+				      NULL, desc);
 }
 
 static inline
@@ -233,8 +237,8 @@ int virtio_find_vqs_ctx(struct virtio_device *vdev, unsigned nvqs,
 			const char * const names[], const bool *ctx,
 			struct irq_affinity *desc)
 {
-	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, ctx,
-				      desc);
+	return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, NULL,
+				      ctx, desc);
 }
 
 /**