[PATCH 1/1] drm/virtio: Implement RESOURCE_GET_LAYOUT ioctl

Julia Zhang julia.zhang at amd.com
Thu Dec 21 10:00:16 UTC 2023


From: Daniel Stone <daniels at collabora.com>

Add a new ioctl to allow the guest VM to discover how the guest
actually allocated the underlying buffer, which allows buffers to
be used for GL<->Vulkan interop and through standard window systems.
It's also a step towards properly supporting modifiers in the guest.

Signed-off-by: Daniel Stone <daniels at collabora.com>
Co-developed-by: Julia Zhang <julia.zhang at amd.com> # support query
stride before it's created
Signed-off-by: Julia Zhang <julia.zhang at amd.com>
---
 drivers/gpu/drm/virtio/virtgpu_drv.c   |  1 +
 drivers/gpu/drm/virtio/virtgpu_drv.h   | 22 ++++++++-
 drivers/gpu/drm/virtio/virtgpu_ioctl.c | 66 ++++++++++++++++++++++++++
 drivers/gpu/drm/virtio/virtgpu_kms.c   |  8 +++-
 drivers/gpu/drm/virtio/virtgpu_vq.c    | 63 ++++++++++++++++++++++++
 include/uapi/drm/virtgpu_drm.h         | 21 ++++++++
 include/uapi/linux/virtio_gpu.h        | 30 ++++++++++++
 7 files changed, 208 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.c b/drivers/gpu/drm/virtio/virtgpu_drv.c
index 4334c7608408..98061b714b98 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.c
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.c
@@ -148,6 +148,7 @@ static unsigned int features[] = {
 	VIRTIO_GPU_F_RESOURCE_UUID,
 	VIRTIO_GPU_F_RESOURCE_BLOB,
 	VIRTIO_GPU_F_CONTEXT_INIT,
+	VIRTIO_GPU_F_RESOURCE_QUERY_LAYOUT,
 };
 static struct virtio_driver virtio_gpu_driver = {
 	.feature_table = features,
diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h
index 96365a772f77..bb5edcfeda54 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.h
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
@@ -214,6 +214,16 @@ struct virtio_gpu_drv_cap_cache {
 	atomic_t is_valid;
 };
 
+struct virtio_gpu_query_info {
+	uint32_t num_planes;
+	uint64_t modifier;
+	struct {
+		uint64_t offset;
+		uint32_t stride;
+	} planes[VIRTIO_GPU_MAX_RESOURCE_PLANES];
+	atomic_t is_valid;
+};
+
 struct virtio_gpu_device {
 	struct drm_device *ddev;
 
@@ -246,6 +256,7 @@ struct virtio_gpu_device {
 	bool has_resource_blob;
 	bool has_host_visible;
 	bool has_context_init;
+	bool has_resource_query_layout;
 	struct virtio_shm_region host_visible_region;
 	struct drm_mm host_visible_mm;
 
@@ -277,7 +288,7 @@ struct virtio_gpu_fpriv {
 };
 
 /* virtgpu_ioctl.c */
-#define DRM_VIRTIO_NUM_IOCTLS 12
+#define DRM_VIRTIO_NUM_IOCTLS 13
 extern struct drm_ioctl_desc virtio_gpu_ioctls[DRM_VIRTIO_NUM_IOCTLS];
 void virtio_gpu_create_context(struct drm_device *dev, struct drm_file *file);
 
@@ -420,6 +431,15 @@ virtio_gpu_cmd_set_scanout_blob(struct virtio_gpu_device *vgdev,
 				uint32_t width, uint32_t height,
 				uint32_t x, uint32_t y);
 
+int
+virtio_gpu_cmd_get_resource_layout(struct virtio_gpu_device *vgdev,
+				   struct virtio_gpu_query_info *bo_info,
+				   uint32_t width,
+				   uint32_t height,
+				   uint32_t format,
+				   uint32_t bind,
+				   uint32_t hw_res_handle);
+
 /* virtgpu_display.c */
 int virtio_gpu_modeset_init(struct virtio_gpu_device *vgdev);
 void virtio_gpu_modeset_fini(struct virtio_gpu_device *vgdev);
diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
index b24b11f25197..216c04314177 100644
--- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c
+++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
@@ -107,6 +107,9 @@ static int virtio_gpu_getparam_ioctl(struct drm_device *dev, void *data,
 	case VIRTGPU_PARAM_SUPPORTED_CAPSET_IDs:
 		value = vgdev->capset_id_mask;
 		break;
+	case VIRTGPU_PARAM_RESOURCE_QUERY_LAYOUT:
+		value = vgdev->has_resource_query_layout ? 1 : 0;
+		break;
 	default:
 		return -EINVAL;
 	}
@@ -668,6 +671,65 @@ static int virtio_gpu_context_init_ioctl(struct drm_device *dev,
 	return ret;
 }
 
+static int virtio_gpu_resource_query_layout_ioctl(struct drm_device *dev,
+						  void *data,
+						  struct drm_file *file)
+{
+	struct drm_virtgpu_resource_query_layout *args = data;
+	struct virtio_gpu_device *vgdev = dev->dev_private;
+	struct drm_gem_object *obj = NULL;
+	struct virtio_gpu_object *bo = NULL;
+	struct virtio_gpu_query_info bo_info = {0};
+	int ret = 0;
+	int i;
+
+	if (!vgdev->has_resource_query_layout) {
+		DRM_ERROR("failing: no RQL on host\n");
+		return -EINVAL;
+	}
+
+	if (args->handle > 0) {
+		obj = drm_gem_object_lookup(file, args->handle);
+		if (obj == NULL) {
+			DRM_ERROR("invalid handle 0x%x\n", args->handle);
+			return -ENOENT;
+		}
+		bo = gem_to_virtio_gpu_obj(obj);
+	}
+
+	ret = virtio_gpu_cmd_get_resource_layout(vgdev, &bo_info, args->width,
+						 args->height, args->format,
+						 args->bind, bo ? bo->hw_res_handle : 0);
+	if (ret)
+		goto out;
+
+	ret = wait_event_timeout(vgdev->resp_wq,
+				 atomic_read(&bo_info.is_valid),
+				 5 * HZ);
+	if (!ret)
+		goto out;
+
+valid:
+	smp_rmb();
+	WARN_ON(atomic_read(&bo_info.is_valid));
+	args->num_planes = bo_info.num_planes;
+	args->modifier = bo_info.modifier;
+	for (i = 0; i < args->num_planes; i++) {
+		args->planes[i].offset = bo_info.planes[i].offset;
+		args->planes[i].stride = bo_info.planes[i].stride;
+	}
+	for (; i < VIRTIO_GPU_MAX_RESOURCE_PLANES; i++) {
+		args->planes[i].offset = 0;
+		args->planes[i].stride = 0;
+	}
+	ret = 0;
+
+out:
+	if (obj)
+		drm_gem_object_put(obj);
+	return ret;
+}
+
 struct drm_ioctl_desc virtio_gpu_ioctls[DRM_VIRTIO_NUM_IOCTLS] = {
 	DRM_IOCTL_DEF_DRV(VIRTGPU_MAP, virtio_gpu_map_ioctl,
 			  DRM_RENDER_ALLOW),
@@ -707,4 +769,8 @@ struct drm_ioctl_desc virtio_gpu_ioctls[DRM_VIRTIO_NUM_IOCTLS] = {
 
 	DRM_IOCTL_DEF_DRV(VIRTGPU_CONTEXT_INIT, virtio_gpu_context_init_ioctl,
 			  DRM_RENDER_ALLOW),
+
+	DRM_IOCTL_DEF_DRV(VIRTGPU_RESOURCE_QUERY_LAYOUT,
+			  virtio_gpu_resource_query_layout_ioctl,
+			  DRM_RENDER_ALLOW),
 };
diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c
index 5a3b5aaed1f3..4f34f4145910 100644
--- a/drivers/gpu/drm/virtio/virtgpu_kms.c
+++ b/drivers/gpu/drm/virtio/virtgpu_kms.c
@@ -175,6 +175,9 @@ int virtio_gpu_init(struct virtio_device *vdev, struct drm_device *dev)
 	if (virtio_has_feature(vgdev->vdev, VIRTIO_GPU_F_RESOURCE_BLOB)) {
 		vgdev->has_resource_blob = true;
 	}
+	if (virtio_has_feature(vgdev->vdev, VIRTIO_GPU_F_RESOURCE_QUERY_LAYOUT)) {
+		vgdev->has_resource_query_layout = true;
+	}
 	if (virtio_get_shm_region(vgdev->vdev, &vgdev->host_visible_region,
 				  VIRTIO_GPU_SHM_ID_HOST_VISIBLE)) {
 		if (!devm_request_mem_region(&vgdev->vdev->dev,
@@ -204,8 +207,9 @@ int virtio_gpu_init(struct virtio_device *vdev, struct drm_device *dev)
 		 vgdev->has_resource_blob ? '+' : '-',
 		 vgdev->has_host_visible ? '+' : '-');
 
-	DRM_INFO("features: %ccontext_init\n",
-		 vgdev->has_context_init ? '+' : '-');
+	DRM_INFO("features: %ccontext_init %cresource_query_layout\n",
+		 vgdev->has_context_init ? '+' : '-',
+		 vgdev->has_resource_query_layout ? '+' : '-');
 
 	ret = virtio_find_vqs(vgdev->vdev, 2, vqs, callbacks, names, NULL);
 	if (ret) {
diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c
index b1a00c0c25a7..26998a3ac4c2 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -1302,3 +1302,66 @@ void virtio_gpu_cmd_set_scanout_blob(struct virtio_gpu_device *vgdev,
 
 	virtio_gpu_queue_ctrl_buffer(vgdev, vbuf);
 }
+
+static void virtio_gpu_cmd_get_resource_layout_cb(struct virtio_gpu_device *vgdev,
+						  struct virtio_gpu_vbuffer *vbuf)
+{
+	struct virtio_gpu_resp_resource_layout *resp =
+		(struct virtio_gpu_resp_resource_layout *)vbuf->resp_buf;
+	struct virtio_gpu_query_info *bo_info = vbuf->resp_cb_data;
+	int i;
+
+	vbuf->resp_cb_data = NULL;
+
+	if (resp->hdr.type != VIRTIO_GPU_RESP_OK_RESOURCE_LAYOUT) {
+		atomic_set(&bo_info->is_valid, 0);
+		goto out;
+	}
+
+	bo_info->modifier = le64_to_cpu(resp->modifier);
+	bo_info->num_planes = le32_to_cpu(resp->num_planes);
+	for (i = 0; i < bo_info->num_planes; i++) {
+		bo_info->planes[i].stride = le32_to_cpu(resp->planes[i].stride);
+		bo_info->planes[i].offset = le32_to_cpu(resp->planes[i].offset);
+	}
+	smp_wmb();
+	atomic_set(&bo_info->is_valid, 1);
+
+out:
+	wake_up_all(&vgdev->resp_wq);
+}
+
+int virtio_gpu_cmd_get_resource_layout(struct virtio_gpu_device *vgdev,
+				       struct virtio_gpu_query_info *bo_info,
+				       uint32_t width,
+				       uint32_t height,
+				       uint32_t format,
+				       uint32_t bind,
+				       uint32_t hw_res_handle)
+{
+	struct virtio_gpu_resource_query_layout *cmd_p;
+	struct virtio_gpu_vbuffer *vbuf;
+	void *resp_buf;
+
+	resp_buf = kzalloc(sizeof(struct virtio_gpu_resp_resource_layout),
+			   GFP_KERNEL);
+	if (!resp_buf)
+		return -ENOMEM;
+
+	cmd_p = virtio_gpu_alloc_cmd_resp
+		(vgdev, &virtio_gpu_cmd_get_resource_layout_cb, &vbuf,
+		 sizeof(*cmd_p), sizeof(struct virtio_gpu_resp_resource_layout),
+		 resp_buf);
+	memset(cmd_p, 0, sizeof(*cmd_p));
+
+	cmd_p->hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_RESOURCE_QUERY_LAYOUT);
+	cmd_p->resource_id = cpu_to_le32(hw_res_handle);
+	cmd_p->width = cpu_to_le32(width);
+	cmd_p->height = cpu_to_le32(height);
+	cmd_p->format = cpu_to_le32(format);
+	cmd_p->bind = cpu_to_le32(bind);
+	vbuf->resp_cb_data = bo_info;
+
+	virtio_gpu_queue_ctrl_buffer(vgdev, vbuf);
+	return 0;
+}
diff --git a/include/uapi/drm/virtgpu_drm.h b/include/uapi/drm/virtgpu_drm.h
index b1d0e56565bc..66f7c0fa1d4d 100644
--- a/include/uapi/drm/virtgpu_drm.h
+++ b/include/uapi/drm/virtgpu_drm.h
@@ -48,6 +48,7 @@ extern "C" {
 #define DRM_VIRTGPU_GET_CAPS  0x09
 #define DRM_VIRTGPU_RESOURCE_CREATE_BLOB 0x0a
 #define DRM_VIRTGPU_CONTEXT_INIT 0x0b
+#define DRM_VIRTGPU_RESOURCE_QUERY_LAYOUT 0x0c
 
 #define VIRTGPU_EXECBUF_FENCE_FD_IN	0x01
 #define VIRTGPU_EXECBUF_FENCE_FD_OUT	0x02
@@ -97,6 +98,7 @@ struct drm_virtgpu_execbuffer {
 #define VIRTGPU_PARAM_CROSS_DEVICE 5 /* Cross virtio-device resource sharing  */
 #define VIRTGPU_PARAM_CONTEXT_INIT 6 /* DRM_VIRTGPU_CONTEXT_INIT */
 #define VIRTGPU_PARAM_SUPPORTED_CAPSET_IDs 7 /* Bitmask of supported capability set ids */
+#define VIRTGPU_PARAM_RESOURCE_QUERY_LAYOUT 8 /* DRM_VIRTGPU_RESOURCE_QUERY_LAYOUT (also needs cap) */
 
 struct drm_virtgpu_getparam {
 	__u64 param;
@@ -211,6 +213,21 @@ struct drm_virtgpu_context_init {
 	__u64 ctx_set_params;
 };
 
+#define VIRTIO_GPU_MAX_RESOURCE_PLANES 4
+struct drm_virtgpu_resource_query_layout {
+	__u32 handle;
+	__u32 width;
+	__u32 height;
+	__u32 format;
+	__u32 bind;
+	__u32 num_planes;
+	__u64 modifier;
+	struct {
+		__u64 offset;
+		__u32 stride;
+	} planes[VIRTIO_GPU_MAX_RESOURCE_PLANES];
+};
+
 /*
  * Event code that's given when VIRTGPU_CONTEXT_PARAM_POLL_RINGS_MASK is in
  * effect.  The event size is sizeof(drm_event), since there is no additional
@@ -261,6 +278,10 @@ struct drm_virtgpu_context_init {
 	DRM_IOWR(DRM_COMMAND_BASE + DRM_VIRTGPU_CONTEXT_INIT,		\
 		struct drm_virtgpu_context_init)
 
+#define DRM_IOCTL_VIRTGPU_RESOURCE_QUERY_LAYOUT				\
+	DRM_IOWR(DRM_COMMAND_BASE + DRM_VIRTGPU_RESOURCE_QUERY_LAYOUT,	\
+		struct drm_virtgpu_resource_query_layout)
+
 #if defined(__cplusplus)
 }
 #endif
diff --git a/include/uapi/linux/virtio_gpu.h b/include/uapi/linux/virtio_gpu.h
index f556fde07b76..547575232376 100644
--- a/include/uapi/linux/virtio_gpu.h
+++ b/include/uapi/linux/virtio_gpu.h
@@ -65,6 +65,11 @@
  */
 #define VIRTIO_GPU_F_CONTEXT_INIT        4
 
+/*
+ * VIRTIO_GPU_CMD_RESOURCE_QUERY_LAYOUT
+ */
+#define VIRTIO_GPU_F_RESOURCE_QUERY_LAYOUT 5
+
 enum virtio_gpu_ctrl_type {
 	VIRTIO_GPU_UNDEFINED = 0,
 
@@ -95,6 +100,7 @@ enum virtio_gpu_ctrl_type {
 	VIRTIO_GPU_CMD_SUBMIT_3D,
 	VIRTIO_GPU_CMD_RESOURCE_MAP_BLOB,
 	VIRTIO_GPU_CMD_RESOURCE_UNMAP_BLOB,
+	VIRTIO_GPU_CMD_RESOURCE_QUERY_LAYOUT,
 
 	/* cursor commands */
 	VIRTIO_GPU_CMD_UPDATE_CURSOR = 0x0300,
@@ -108,6 +114,7 @@ enum virtio_gpu_ctrl_type {
 	VIRTIO_GPU_RESP_OK_EDID,
 	VIRTIO_GPU_RESP_OK_RESOURCE_UUID,
 	VIRTIO_GPU_RESP_OK_MAP_INFO,
+	VIRTIO_GPU_RESP_OK_RESOURCE_LAYOUT,
 
 	/* error responses */
 	VIRTIO_GPU_RESP_ERR_UNSPEC = 0x1200,
@@ -453,4 +460,27 @@ struct virtio_gpu_resource_unmap_blob {
 	__le32 padding;
 };
 
+/* VIRTIO_GPU_CMD_RESOURCE_QUERY_LAYOUT */
+struct virtio_gpu_resource_query_layout {
+	struct virtio_gpu_ctrl_hdr hdr;
+	__le32 resource_id;
+	__le32 width;
+	__le32 height;
+	__le32 format;
+	__le32 bind;
+};
+
+
+/* VIRTIO_GPU_RESP_OK_RESOURCE_LAYOUT */
+#define VIRTIO_GPU_RES_MAX_PLANES 4
+struct virtio_gpu_resp_resource_layout {
+	struct virtio_gpu_ctrl_hdr hdr;
+	__le64 modifier;
+	__le32 num_planes;
+	struct virtio_gpu_resource_plane {
+		__le64 offset;
+		__le32 stride;
+	} planes[VIRTIO_GPU_RES_MAX_PLANES];
+};
+
 #endif
-- 
2.34.1



More information about the amd-gfx mailing list