freedreno/drm/virtio: Use userspace IOVA allocation

If supported by host virglrenderer and host kernel, use userspace
allocated GPU virtual addresses.  This lets us avoid stalling on
waiting for response from host kernel until we need to know the
host handle (which is usually not until submit time).

Handling the async response from host to get host_handle is done
thru the submit_queue, so that in the submit path (hot) we do not
need any additional synchronization to know that the host_handle
is valid.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16086>

include/drm-uapi/msm_drm.h

@@ -82,6 +82,10 @@ struct drm_msm_timespec {
 #define MSM_PARAM_FAULTS     0x09  /* RO */
 #define MSM_PARAM_SUSPENDS   0x0a  /* RO */
 #define MSM_PARAM_SYSPROF    0x0b  /* WO: 1 preserves perfcntrs, 2 also disables suspend */
+#define MSM_PARAM_COMM       0x0c  /* WO: override for task->comm */
+#define MSM_PARAM_CMDLINE    0x0d  /* WO: override for task cmdline */
+#define MSM_PARAM_VA_START   0x0e  /* RO: start of valid GPU iova range */
+#define MSM_PARAM_VA_SIZE    0x0f  /* RO: size of valid GPU iova range (bytes) */
 
 /* For backwards compat.  The original support for preemption was based on
  * a single ring per priority level so # of priority levels equals the #
@@ -95,6 +99,8 @@ struct drm_msm_param {
 	__u32 pipe;           /* in, MSM_PIPE_x */
 	__u32 param;          /* in, MSM_PARAM_x */
 	__u64 value;          /* out (get_param) or in (set_param) */
+	__u32 len;            /* zero for non-pointer params */
+	__u32 pad;            /* must be zero */
 };
 
 /*
@@ -131,6 +137,7 @@ struct drm_msm_gem_new {
 #define MSM_INFO_GET_IOVA	0x01   /* get iova, returned by value */
 #define MSM_INFO_SET_NAME	0x02   /* set the debug name (by pointer) */
 #define MSM_INFO_GET_NAME	0x03   /* get debug name, returned by pointer */
+#define MSM_INFO_SET_IOVA	0x04   /* set the iova, passed by value */
 
 struct drm_msm_gem_info {
 	__u32 handle;         /* in */