drm/virtio: add virtio_gpu_alloc_fence()

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>
Link: http://patchwork.freedesktop.org/patch/msgid/20181112165157.32765-2-robert.foss@collabora.com
Suggested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h
index 6474e83..acd130c 100644 (file)
--- 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 00c742a..6b5d922 100644 (file)
--- 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 bc5afa4..d69fc35 100644 (file)
--- 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 a9f4ae7..b84ac8c 100644 (file)
--- 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 51bef17..93f2c3a 100644 (file)
--- 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);