[PATCH v4 1/4] drm/virtio: add virtio_gpu_alloc_fence()

Robert Foss
2018-11-05T11:42:43Z

Refactor fence creation, add fences to relevant GPU
operations and add cursor helper functions.

This removes the potential for allocation failures from the
cmd_submit and atomic_commit paths.
Now a fence will be allocated first and only after that
will we proceed with the rest of the execution.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com>
Signed-off-by: Robert Foss <robert.foss@collabora.com>
Suggested-by: Rob Herring <robh@kernel.org>
---
Changes since v3:
- Gerd: Clarified and extended commit message
- Emil: Fixed whitespace issue
- Emil: Changed label name from fail_fence to fail_backoff
- Emil: Remove special case for !fence->drv in virtio_gpu_fence_cleanup()

drivers/gpu/drm/virtio/virtgpu_drv.h | 4 +++
drivers/gpu/drm/virtio/virtgpu_fence.c | 29 ++++++++++++----
drivers/gpu/drm/virtio/virtgpu_ioctl.c | 30 +++++++++++++++--
drivers/gpu/drm/virtio/virtgpu_plane.c | 46 +++++++++++++++++++++++---
drivers/gpu/drm/virtio/virtgpu_vq.c | 2 +-
5 files changed, 96 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h
index 6474e83cbf3d..acd130c58e33 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.h
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
@@ -131,6 +131,7 @@ struct virtio_gpu_framebuffer {
int x1, y1, x2, y2; /* dirty rect */
spinlock_t dirty_lock;
uint32_t hw_res_handle;
+ struct virtio_gpu_fence *fence;
};
#define to_virtio_gpu_framebuffer(x) \
container_of(x, struct virtio_gpu_framebuffer, base)
@@ -349,6 +350,9 @@ void virtio_gpu_ttm_fini(struct virtio_gpu_device *vgdev);
int virtio_gpu_mmap(struct file *filp, struct vm_area_struct *vma);

/* virtio_gpu_fence.c */
+struct virtio_gpu_fence *virtio_gpu_fence_alloc(
+ struct virtio_gpu_device *vgdev);
+void virtio_gpu_fence_cleanup(struct virtio_gpu_fence *fence);
int virtio_gpu_fence_emit(struct virtio_gpu_device *vgdev,
struct virtio_gpu_ctrl_hdr *cmd_hdr,
struct virtio_gpu_fence **fence);
diff --git a/drivers/gpu/drm/virtio/virtgpu_fence.c b/drivers/gpu/drm/virtio/virtgpu_fence.c
index 00c742a441bf..6b5d92215cfb 100644
--- a/drivers/gpu/drm/virtio/virtgpu_fence.c
+++ b/drivers/gpu/drm/virtio/virtgpu_fence.c
@@ -67,6 +67,28 @@ static const struct dma_fence_ops virtio_fence_ops = {
.timeline_value_str = virtio_timeline_value_str,
};

+struct virtio_gpu_fence *virtio_gpu_fence_alloc(struct virtio_gpu_device *vgdev)
+{
+ struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
+ struct virtio_gpu_fence *fence = kzalloc(sizeof(struct virtio_gpu_fence),
+ GFP_ATOMIC);
+ if (!fence)
+ return fence;
+
+ fence->drv = drv;
+ dma_fence_init(&fence->f, &virtio_fence_ops, &drv->lock, drv->context, 0);
+
+ return fence;
+}
+
+void virtio_gpu_fence_cleanup(struct virtio_gpu_fence *fence)
+{
+ if (!fence)
+ return;
+
+ dma_fence_put(&fence->f);
+}
+
int virtio_gpu_fence_emit(struct virtio_gpu_device *vgdev,
struct virtio_gpu_ctrl_hdr *cmd_hdr,
struct virtio_gpu_fence **fence)
@@ -74,15 +96,8 @@ int virtio_gpu_fence_emit(struct virtio_gpu_device *vgdev,
struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
unsigned long irq_flags;

- *fence = kmalloc(sizeof(struct virtio_gpu_fence), GFP_ATOMIC);
- if ((*fence) == NULL)
- return -ENOMEM;
-
spin_lock_irqsave(&drv->lock, irq_flags);
- (*fence)->drv = drv;
(*fence)->seq = ++drv->sync_seq;
- dma_fence_init(&(*fence)->f, &virtio_fence_ops, &drv->lock,
- drv->context, (*fence)->seq);
dma_fence_get(&(*fence)->f);
list_add_tail(&(*fence)->node, &drv->fences);
spin_unlock_irqrestore(&drv->lock, irq_flags);
diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
index bc5afa4f906e..d69fc356df0a 100644
--- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c
+++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
@@ -168,6 +168,13 @@ static int virtio_gpu_execbuffer_ioctl(struct drm_device *dev, void *data,
ret = PTR_ERR(buf);
goto out_unresv;
}
+
+ fence = virtio_gpu_fence_alloc(vgdev);
+ if (!fence) {
+ kfree(buf);
+ ret = -ENOMEM;
+ goto out_unresv;
+ }
virtio_gpu_cmd_submit(vgdev, buf, exbuf->size,
vfpriv->ctx_id, &fence);

@@ -283,11 +290,17 @@ static int virtio_gpu_resource_create_ioctl(struct drm_device *dev, void *data,
rc_3d.nr_samples = cpu_to_le32(rc->nr_samples);
rc_3d.flags = cpu_to_le32(rc->flags);

+ fence = virtio_gpu_fence_alloc(vgdev);
+ if (!fence) {
+ ret = -ENOMEM;
+ goto fail_backoff;
+ }
+
virtio_gpu_cmd_resource_create_3d(vgdev, qobj, &rc_3d, NULL);
ret = virtio_gpu_object_attach(vgdev, qobj, &fence);
if (ret) {
- ttm_eu_backoff_reservation(&ticket, &validate_list);
- goto fail_unref;
+ virtio_gpu_fence_cleanup(fence);
+ goto fail_backoff;
}
ttm_eu_fence_buffer_objects(&ticket, &validate_list, &fence->f);
}
@@ -312,6 +325,8 @@ static int virtio_gpu_resource_create_ioctl(struct drm_device *dev, void *data,
dma_fence_put(&fence->f);
}
return 0;
+fail_backoff:
+ ttm_eu_backoff_reservation(&ticket, &validate_list);
fail_unref:
if (vgdev->has_virgl_3d) {
virtio_gpu_unref_list(&validate_list);
@@ -374,6 +389,12 @@ static int virtio_gpu_transfer_from_host_ioctl(struct drm_device *dev,
goto out_unres;

convert_to_hw_box(&box, &args->box);
+
+ fence = virtio_gpu_fence_alloc(vgdev);
+ if (!fence) {
+ ret = -ENOMEM;
+ goto out_unres;
+ }
virtio_gpu_cmd_transfer_from_host_3d
(vgdev, qobj->hw_res_handle,
vfpriv->ctx_id, offset, args->level,
@@ -423,6 +444,11 @@ static int virtio_gpu_transfer_to_host_ioctl(struct drm_device *dev, void *data,
(vgdev, qobj, offset,
box.w, box.h, box.x, box.y, NULL);
} else {
+ fence = virtio_gpu_fence_alloc(vgdev);
+ if (!fence) {
+ ret = -ENOMEM;
+ goto out_unres;
+ }
virtio_gpu_cmd_transfer_to_host_3d
(vgdev, qobj,
vfpriv ? vfpriv->ctx_id : 0, offset,
diff --git a/drivers/gpu/drm/virtio/virtgpu_plane.c b/drivers/gpu/drm/virtio/virtgpu_plane.c
index a9f4ae7d4483..b84ac8c25856 100644
--- a/drivers/gpu/drm/virtio/virtgpu_plane.c
+++ b/drivers/gpu/drm/virtio/virtgpu_plane.c
@@ -137,6 +137,41 @@ static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
plane->state->src_h >> 16);
}

+static int virtio_gpu_cursor_prepare_fb(struct drm_plane *plane,
+ struct drm_plane_state *new_state)
+{
+ struct drm_device *dev = plane->dev;
+ struct virtio_gpu_device *vgdev = dev->dev_private;
+ struct virtio_gpu_framebuffer *vgfb;
+ struct virtio_gpu_object *bo;
+
+ if (!new_state->fb)
+ return 0;
+
+ vgfb = to_virtio_gpu_framebuffer(new_state->fb);
+ bo = gem_to_virtio_gpu_obj(vgfb->base.obj[0]);
+ if (bo && bo->dumb && (plane->state->fb != new_state->fb)) {
+ vgfb->fence = virtio_gpu_fence_alloc(vgdev);
+ if (!vgfb->fence)
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static void virtio_gpu_cursor_cleanup_fb(struct drm_plane *plane,
+ struct drm_plane_state *old_state)
+{
+ struct virtio_gpu_framebuffer *vgfb;
+
+ if (!plane->state->fb)
+ return;
+
+ vgfb = to_virtio_gpu_framebuffer(plane->state->fb);
+ if (vgfb->fence)
+ virtio_gpu_fence_cleanup(vgfb->fence);
+}
+
static void virtio_gpu_cursor_plane_update(struct drm_plane *plane,
struct drm_plane_state *old_state)
{
@@ -144,7 +179,6 @@ static void virtio_gpu_cursor_plane_update(struct drm_plane *plane,
struct virtio_gpu_device *vgdev = dev->dev_private;
struct virtio_gpu_output *output = NULL;
struct virtio_gpu_framebuffer *vgfb;
- struct virtio_gpu_fence *fence = NULL;
struct virtio_gpu_object *bo = NULL;
uint32_t handle;
int ret = 0;
@@ -170,13 +204,13 @@ static void virtio_gpu_cursor_plane_update(struct drm_plane *plane,
(vgdev, bo, 0,
cpu_to_le32(plane->state->crtc_w),
cpu_to_le32(plane->state->crtc_h),
- 0, 0, &fence);
+ 0, 0, &vgfb->fence);
ret = virtio_gpu_object_reserve(bo, false);
if (!ret) {
reservation_object_add_excl_fence(bo->tbo.resv,
- &fence->f);
- dma_fence_put(&fence->f);
- fence = NULL;
+ &vgfb->fence->f);
+ dma_fence_put(&vgfb->fence->f);
+ vgfb->fence = NULL;
virtio_gpu_object_unreserve(bo);
virtio_gpu_object_wait(bo, false);
}
@@ -218,6 +252,8 @@ static const struct drm_plane_helper_funcs virtio_gpu_primary_helper_funcs = {
};

static const struct drm_plane_helper_funcs virtio_gpu_cursor_helper_funcs = {
+ .prepare_fb = virtio_gpu_cursor_prepare_fb,
+ .cleanup_fb = virtio_gpu_cursor_cleanup_fb,
.atomic_check = virtio_gpu_plane_atomic_check,
.atomic_update = virtio_gpu_cursor_plane_update,
};
diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c
index 51bef1775e47..93f2c3a51ee8 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -896,9 +896,9 @@ void virtio_gpu_object_detach(struct virtio_gpu_device *vgdev,
struct virtio_gpu_object *obj)
{
bool use_dma_api = !virtio_has_iommu_quirk(vgdev->vdev);
- struct virtio_gpu_fence *fence;

if (use_dma_api && obj->mapped) {
+ struct virtio_gpu_fence *fence = virtio_gpu_fence_alloc(vgdev);
/* detach backing and wait for the host process it ... */
virtio_gpu_cmd_resource_inval_backing(vgdev, obj->hw_res_handle, &fence);
dma_fence_wait(&fence->f, true);
--
2.17.1