The current virtgpu implementation of poll(..) drops events
when VIRTGPU_CONTEXT_PARAM_POLL_RINGS_MASK is enabled (otherwise
it's like a normal DRM driver).
This is because paravirtualized userspaces receives responses in a
buffer of type BLOB_MEM_GUEST, not by read(..).
To be in line with other DRM drivers and avoid specialized behavior,
it is possible to define a dummy event for virtgpu. Paravirtualized
userspace will now have to call read(..) on the DRM fd to receive the
dummy event.
Fixes: b10790434c ("drm/virtgpu api: create context init feature")
Reported-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20211122232210.602-2-gurchetansingh@google.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
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>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-12-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
For the Sommelier guest Wayland proxy, it's desirable for the
DRM fd to be pollable in response to an host compositor event.
This can also be used by the 3D driver to poll events on a CPU
timeline.
This enables the DRM fd associated with a particular 3D context
to be polled independent of KMS events. The parameter
VIRTGPU_CONTEXT_PARAM_POLL_RINGS_MASK specifies the pollable
rings.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Nicholas Verne <nverne@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-11-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
These were defined in the previous commit. We'll need these
parameters when allocating a dma_fence. The use case for this
is multiple synchronizations timelines.
The maximum number of timelines per 3D instance will be 32. Usually,
only 2 are needed -- one for CPU commands, and another for GPU
commands.
As such, we'll need to specify these parameters when allocating a
dma_fence.
vgdev->fence_drv.context is the "default" fence context for 2D mode
and old userspace.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-8-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Each fence should be associated with a [fence ID, fence_context,
seqno]. The seqno number is just the fence id.
To get the fence context, we add the ring_idx to the 3D context's
base_fence_ctx. The ring_idx is between 0 and 31, inclusive.
Each 3D context will have it's own base_fence_ctx. The ring_idx will
be emitted to host userspace, when emit_fence_info is true.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-7-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This implements the context initialization ioctl. A list of params
is passed in by userspace, and kernel driver validates them. The
only currently supported param is VIRTGPU_CONTEXT_PARAM_CAPSET_ID.
If the context has already been initialized, -EEXIST is returned.
This happens after Linux userspace does dumb_create + followed by
opening the Mesa virgl driver with the same virtgpu instance.
However, for most applications, 3D contexts will be explicitly
initialized when the feature is available.
Signed-off-by: Anthoine Bourgeois <anthoine.bourgeois@gmail.com>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-6-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
When kmem_cache_zalloc in virtio_gpu_get_vbuf fails, it will return
an error code. But none of its callers checks this error code, and
a core dump will take place.
Considering many of its callers can't handle such error, I add
a __GFP_NOFAIL flag when calling kmem_cache_zalloc to make sure
it won't fail, and delete those unused error handlings.
Fixes: dc5698e80c ("Add virtio gpu driver.")
Signed-off-by: Yuntao Liu <liuyuntao10@huawei.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210828104321.3410312-1-liuyuntao10@huawei.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>