If userspace never maps GEM object, then BO wastes hostmem space
because VirtIO-GPU driver maps VRAM BO at the BO's creating time.
Make mappings on-demand by adding new RESOURCE_CREATE_BLOB IOCTL/UAPI
hinting flag telling that host mapping should be deferred until first
mapping is made when the flag is set by userspace.
Signed-off-by: Dmitry Osipenko <dmitry.osipe...@collabora.com>
---
drivers/gpu/drm/virtio/virtgpu_drv.h | 2 ++
drivers/gpu/drm/virtio/virtgpu_gem.c | 9 ++++++++
drivers/gpu/drm/virtio/virtgpu_ioctl.c | 1 +
drivers/gpu/drm/virtio/virtgpu_vram.c | 30 +++++++++++++++++++++-----
include/uapi/drm/virtgpu_drm.h | 4 ++++
5 files changed, 41 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h
b/drivers/gpu/drm/virtio/virtgpu_drv.h
index 64c236169db8..e5db91a3e8ba 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.h
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
@@ -85,6 +85,7 @@ struct virtio_gpu_object_params {
uint32_t blob_mem;
uint32_t blob_flags;
uint64_t blob_id;
+ uint32_t blob_hints;
};
struct virtio_gpu_object {
@@ -483,6 +484,7 @@ struct sg_table *virtio_gpu_vram_map_dma_buf(struct
virtio_gpu_object *bo,
void virtio_gpu_vram_unmap_dma_buf(struct device *dev,
struct sg_table *sgt,
enum dma_data_direction dir);
+void virtio_gpu_vram_map_deferred(struct virtio_gpu_object_vram *vram);
/* virtgpu_submit.c */
int virtio_gpu_execbuffer_ioctl(struct drm_device *dev, void *data,
diff --git a/drivers/gpu/drm/virtio/virtgpu_gem.c
b/drivers/gpu/drm/virtio/virtgpu_gem.c
index 7db48d17ee3a..c902b68cc25a 100644
--- a/drivers/gpu/drm/virtio/virtgpu_gem.c
+++ b/drivers/gpu/drm/virtio/virtgpu_gem.c
@@ -103,12 +103,21 @@ int virtio_gpu_mode_dumb_mmap(struct drm_file *file_priv,
struct drm_device *dev,
uint32_t handle, uint64_t *offset_p)
{
+ struct virtio_gpu_object_vram *vram;
+ struct virtio_gpu_object *bo;
struct drm_gem_object *gobj;
BUG_ON(!offset_p);
gobj = drm_gem_object_lookup(file_priv, handle);
if (gobj == NULL)
return -ENOENT;
+
+ bo = gem_to_virtio_gpu_obj(gobj);
+ if (virtio_gpu_is_vram(bo)) {
+ vram = to_virtio_gpu_vram(bo);
+ virtio_gpu_vram_map_deferred(vram);
+ }
+
*offset_p = drm_vma_node_offset_addr(&gobj->vma_node);
drm_gem_object_put(gobj);
return 0;
diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c
b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
index e4f76f315550..51544ee8d3c3 100644
--- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c
+++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
@@ -489,6 +489,7 @@ static int verify_blob(struct virtio_gpu_device *vgdev,
params->size = rc_blob->size;
params->blob = true;
params->blob_flags = rc_blob->blob_flags;
+ params->blob_hints = rc_blob->blob_hints;
return 0;
}
diff --git a/drivers/gpu/drm/virtio/virtgpu_vram.c
b/drivers/gpu/drm/virtio/virtgpu_vram.c
index 25df81c02783..d72c93e06a4a 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vram.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vram.c
@@ -41,6 +41,11 @@ static int virtio_gpu_vram_mmap(struct drm_gem_object *obj,
if (!(bo->blob_flags & VIRTGPU_BLOB_FLAG_USE_MAPPABLE))
return -EINVAL;
+ virtio_gpu_vram_map_deferred(vram);
+
+ if (vram->map_state == STATE_INITIALIZING)
+ virtio_gpu_notify(vgdev);
+
wait_event(vgdev->resp_wq, vram->map_state != STATE_INITIALIZING);
if (vram->map_state != STATE_OK)
return -EINVAL;
@@ -215,14 +220,29 @@ int virtio_gpu_vram_create(struct virtio_gpu_device
*vgdev,
virtio_gpu_cmd_resource_create_blob(vgdev, &vram->base, params, NULL,
0);
- if (params->blob_flags & VIRTGPU_BLOB_FLAG_USE_MAPPABLE) {
- ret = virtio_gpu_vram_map(&vram->base);
- if (ret) {
- virtio_gpu_vram_free(obj);
- return ret;
+ if (!(params->blob_hints & DRM_VIRTGPU_BLOB_FLAG_HINT_DEFER_MAPPING)) {
+ if (params->blob_flags & VIRTGPU_BLOB_FLAG_USE_MAPPABLE) {
+ ret = virtio_gpu_vram_map(&vram->base);
+ if (ret) {
+ virtio_gpu_vram_free(obj);
+ return ret;
+ }
}
}
*bo_ptr = &vram->base;
return 0;
}
+
+void virtio_gpu_vram_map_deferred(struct virtio_gpu_object_vram *vram)
+{
+ static DEFINE_MUTEX(map_lock);
+
+ if (!(vram->base.blob_flags & VIRTGPU_BLOB_FLAG_USE_MAPPABLE))
+ return;
+
+ mutex_lock(&map_lock);
+ if (!drm_mm_node_allocated(&vram->vram_node))
+ virtio_gpu_vram_map(&vram->base);
+ mutex_unlock(&map_lock);
+}
diff --git a/include/uapi/drm/virtgpu_drm.h b/include/uapi/drm/virtgpu_drm.h
index c2ce71987e9b..3004a1d08570 100644
--- a/include/uapi/drm/virtgpu_drm.h
+++ b/include/uapi/drm/virtgpu_drm.h
@@ -194,6 +194,10 @@ struct drm_virtgpu_resource_create_blob {
__u32 cmd_size;
__u64 cmd;
__u64 blob_id;
+
+#define DRM_VIRTGPU_BLOB_FLAG_HINT_DEFER_MAPPING 0x0001
+ __u32 blob_hints;
+ __u32 pad2;
};
#define VIRTGPU_CONTEXT_PARAM_CAPSET_ID 0x0001
--
2.47.1
