Similar to DRM_VMW_EVENT_FENCE_SIGNALED. Sends a pollable event to the DRM file descriptor when a fence on a specific ring is signaled.
One difference is the event is not exposed via the UAPI -- this is because host responses are on a shared memory buffer of type BLOB_MEM_GUEST [this is the common way to receive responses with virtgpu]. As such, there is no context specific read(..) implementation either -- just a poll(..) implementation.
Signed-off-by: Gurchetan Singh gurchetansingh@chromium.org Acked-by: Nicholas Verne nverne@chromium.org --- drivers/gpu/drm/virtio/virtgpu_drv.c | 43 +++++++++++++++++++++++++- drivers/gpu/drm/virtio/virtgpu_drv.h | 7 +++++ drivers/gpu/drm/virtio/virtgpu_fence.c | 10 ++++++ drivers/gpu/drm/virtio/virtgpu_ioctl.c | 34 ++++++++++++++++++++ 4 files changed, 93 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.c b/drivers/gpu/drm/virtio/virtgpu_drv.c index 9d963f1fda8f..749db18dcfa2 100644 --- a/drivers/gpu/drm/virtio/virtgpu_drv.c +++ b/drivers/gpu/drm/virtio/virtgpu_drv.c @@ -29,6 +29,8 @@ #include <linux/module.h> #include <linux/console.h> #include <linux/pci.h> +#include <linux/poll.h> +#include <linux/wait.h>
#include <drm/drm.h> #include <drm/drm_aperture.h> @@ -155,6 +157,35 @@ static void virtio_gpu_config_changed(struct virtio_device *vdev) schedule_work(&vgdev->config_changed_work); }
+static __poll_t virtio_gpu_poll(struct file *filp, + struct poll_table_struct *wait) +{ + struct drm_file *drm_file = filp->private_data; + struct virtio_gpu_fpriv *vfpriv = drm_file->driver_priv; + struct drm_device *dev = drm_file->minor->dev; + struct drm_pending_event *e = NULL; + __poll_t mask = 0; + + if (!vfpriv->ring_idx_mask) + return drm_poll(filp, wait); + + poll_wait(filp, &drm_file->event_wait, wait); + + if (!list_empty(&drm_file->event_list)) { + spin_lock_irq(&dev->event_lock); + e = list_first_entry(&drm_file->event_list, + struct drm_pending_event, link); + drm_file->event_space += e->event->length; + list_del(&e->link); + spin_unlock_irq(&dev->event_lock); + + kfree(e); + mask |= EPOLLIN | EPOLLRDNORM; + } + + return mask; +} + static struct virtio_device_id id_table[] = { { VIRTIO_ID_GPU, VIRTIO_DEV_ANY_ID }, { 0 }, @@ -194,7 +225,17 @@ MODULE_AUTHOR("Dave Airlie airlied@redhat.com"); MODULE_AUTHOR("Gerd Hoffmann kraxel@redhat.com"); MODULE_AUTHOR("Alon Levy");
-DEFINE_DRM_GEM_FOPS(virtio_gpu_driver_fops); +static const struct file_operations virtio_gpu_driver_fops = { + .owner = THIS_MODULE, + .open = drm_open, + .release = drm_release, + .unlocked_ioctl = drm_ioctl, + .compat_ioctl = drm_compat_ioctl, + .poll = virtio_gpu_poll, + .read = drm_read, + .llseek = noop_llseek, + .mmap = drm_gem_mmap +};
static const struct drm_driver driver = { .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_RENDER | DRIVER_ATOMIC, diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h index cb60d52c2bd1..e0265fe74aa5 100644 --- a/drivers/gpu/drm/virtio/virtgpu_drv.h +++ b/drivers/gpu/drm/virtio/virtgpu_drv.h @@ -138,11 +138,18 @@ struct virtio_gpu_fence_driver { spinlock_t lock; };
+#define VIRTGPU_EVENT_FENCE_SIGNALED_INTERNAL 0x10000000 +struct virtio_gpu_fence_event { + struct drm_pending_event base; + struct drm_event event; +}; + struct virtio_gpu_fence { struct dma_fence f; uint32_t ring_idx; uint64_t fence_id; bool emit_fence_info; + struct virtio_gpu_fence_event *e; struct virtio_gpu_fence_driver *drv; struct list_head node; }; diff --git a/drivers/gpu/drm/virtio/virtgpu_fence.c b/drivers/gpu/drm/virtio/virtgpu_fence.c index 98a00c1e654d..f28357dbde35 100644 --- a/drivers/gpu/drm/virtio/virtgpu_fence.c +++ b/drivers/gpu/drm/virtio/virtgpu_fence.c @@ -152,11 +152,21 @@ void virtio_gpu_fence_event_process(struct virtio_gpu_device *vgdev, continue;
dma_fence_signal_locked(&curr->f); + if (curr->e) { + drm_send_event(vgdev->ddev, &curr->e->base); + curr->e = NULL; + } + list_del(&curr->node); dma_fence_put(&curr->f); }
dma_fence_signal_locked(&signaled->f); + if (signaled->e) { + drm_send_event(vgdev->ddev, &signaled->e->base); + signaled->e = NULL; + } + list_del(&signaled->node); dma_fence_put(&signaled->f); break; diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c index be7b22a03884..fdaa7f3d9eeb 100644 --- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c +++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c @@ -38,6 +38,36 @@ VIRTGPU_BLOB_FLAG_USE_SHAREABLE | \ VIRTGPU_BLOB_FLAG_USE_CROSS_DEVICE)
+static int virtio_gpu_fence_event_create(struct drm_device *dev, + struct drm_file *file, + struct virtio_gpu_fence *fence, + uint32_t ring_idx) +{ + struct virtio_gpu_fpriv *vfpriv = file->driver_priv; + struct virtio_gpu_fence_event *e = NULL; + int ret; + + if (!(vfpriv->ring_idx_mask & (1 << ring_idx))) + return 0; + + e = kzalloc(sizeof(*e), GFP_KERNEL); + if (!e) + return -ENOMEM; + + e->event.type = VIRTGPU_EVENT_FENCE_SIGNALED_INTERNAL; + e->event.length = sizeof(e->event); + + ret = drm_event_reserve_init(dev, file, &e->base, &e->event); + if (ret) + goto free; + + fence->e = e; + return 0; +free: + kfree(e); + return ret; +} + /* Must be called with &virtio_gpu_fpriv.struct_mutex held. */ static void virtio_gpu_create_context_locked(struct virtio_gpu_device *vgdev, struct virtio_gpu_fpriv *vfpriv) @@ -195,6 +225,10 @@ static int virtio_gpu_execbuffer_ioctl(struct drm_device *dev, void *data, goto out_unresv; }
+ ret = virtio_gpu_fence_event_create(dev, file, out_fence, ring_idx); + if (ret) + goto out_unresv; + if (out_fence_fd >= 0) { sync_file = sync_file_create(&out_fence->f); if (!sync_file) {