Add a userptr address field so userspace can request a blob backed by an existing process mapping. A non-zero userptr selects that path; probe VIRTGPU_PARAM_USERPTR before using the field.
GPU-readonly backing is requested with the virtio CREATE_BLOB wire flag VIRTIO_GPU_BLOB_FLAG_USE_READONLY (also VIRTGPU_BLOB_FLAG_USE_READONLY). The device MUST NOT write such a resource. The guest pins without FOLL_WRITE only when the device advertised VIRTIO_GPU_F_BLOB_READONLY (VIRTGPU_PARAM_BLOB_READONLY). Signed-off-by: Honglei Huang <[email protected]> --- include/uapi/drm/virtgpu_drm.h | 10 ++++++++++ include/uapi/linux/virtio_gpu.h | 5 +++++ 2 files changed, 15 insertions(+) diff --git a/include/uapi/drm/virtgpu_drm.h b/include/uapi/drm/virtgpu_drm.h index 9b886e9772..c890c754d8 100644 --- a/include/uapi/drm/virtgpu_drm.h +++ b/include/uapi/drm/virtgpu_drm.h @@ -99,6 +99,8 @@ struct drm_virtgpu_execbuffer { #define VIRTGPU_PARAM_SUPPORTED_CAPSET_IDs 7 /* Bitmask of supported capability set ids */ #define VIRTGPU_PARAM_EXPLICIT_DEBUG_NAME 8 /* Ability to set debug name from userspace */ #define VIRTGPU_PARAM_BLOB_ALIGNMENT 9 /* Device alignment requirements for blobs */ +#define VIRTGPU_PARAM_USERPTR 10 /* CREATE_BLOB userptr field is supported */ +#define VIRTGPU_PARAM_BLOB_READONLY 11 /* VIRTGPU_BLOB_FLAG_USE_READONLY is honored */ struct drm_virtgpu_getparam { __u64 param; @@ -187,6 +189,7 @@ struct drm_virtgpu_resource_create_blob { #define VIRTGPU_BLOB_FLAG_USE_MAPPABLE 0x0001 #define VIRTGPU_BLOB_FLAG_USE_SHAREABLE 0x0002 #define VIRTGPU_BLOB_FLAG_USE_CROSS_DEVICE 0x0004 +#define VIRTGPU_BLOB_FLAG_USE_READONLY 0x0008 /* zero is invalid blob_mem */ __u32 blob_mem; __u32 blob_flags; @@ -206,6 +209,13 @@ struct drm_virtgpu_resource_create_blob { #define DRM_VIRTGPU_BLOB_FLAG_HINT_DEFER_MAPPING 0x0001 __u32 blob_hints; __u32 pad2; + + /* + * Non-zero selects the userptr path and is valid only with + * VIRTGPU_BLOB_MEM_GUEST. Must be 0 otherwise. Probe + * VIRTGPU_PARAM_USERPTR before using this field. + */ + __u64 userptr; }; #define VIRTGPU_CONTEXT_PARAM_CAPSET_ID 0x0001 diff --git a/include/uapi/linux/virtio_gpu.h b/include/uapi/linux/virtio_gpu.h index e22049835e..af95374758 100644 --- a/include/uapi/linux/virtio_gpu.h +++ b/include/uapi/linux/virtio_gpu.h @@ -72,6 +72,10 @@ * must be aligned to that value. */ #define VIRTIO_GPU_F_BLOB_ALIGNMENT 5 +/* + * VIRTIO_GPU_BLOB_FLAG_USE_READONLY + */ +#define VIRTIO_GPU_F_BLOB_READONLY 6 enum virtio_gpu_ctrl_type { VIRTIO_GPU_UNDEFINED = 0, @@ -415,6 +419,7 @@ struct virtio_gpu_resource_create_blob { #define VIRTIO_GPU_BLOB_FLAG_USE_MAPPABLE 0x0001 #define VIRTIO_GPU_BLOB_FLAG_USE_SHAREABLE 0x0002 #define VIRTIO_GPU_BLOB_FLAG_USE_CROSS_DEVICE 0x0004 +#define VIRTIO_GPU_BLOB_FLAG_USE_READONLY 0x0008 /* zero is invalid blob mem */ __le32 blob_mem; __le32 blob_flags; -- 2.34.1
