The original methods for reading and writing to GPU buffers naively
assumed that the mappings returned by GBM were to the first byte in the
buffer. In fact, the returned mapping is to the first pixel of the
mapped rectangle. This would lead to segaults when the copy routine
would breeze past the end of the mapping into segault territory.
This change fixes the read and write algorithms and adds lots more guard
rails in to prevent future undefined behavior (hopefully).
TEST=boot kernel with VT and VIRTIO_GPU
BUG=None
Change-Id: Ia7c968b6dd274551b6d218e2f0b255af6e55bd35
Reviewed-on: https://chromium-review.googlesource.com/1102110
Commit-Ready: Zach Reizner <zachr@chromium.org>
Tested-by: Zach Reizner <zachr@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>
Multi-plane DMABufs are useful for efficient video playback. The
guest can already use this but has to guess the stride and offsets
for the second and third plane as they are not passed by virtwl
to the guest kernel.
This extracts the correct strides and offsets for each buffer and
passes them back to the guest in the allocation response message.
BUG=chromium:837209
TEST=sommelier can use nv12 buffers without guessing stride/offset
Change-Id: I36ae2fad6605293c907802121676296cbc607a57
Reviewed-on: https://chromium-review.googlesource.com/1070799
Commit-Ready: David Reveman <reveman@chromium.org>
Tested-by: David Reveman <reveman@chromium.org>
Reviewed-by: Zach Reizner <zachr@chromium.org>
name/date/desc_len fields of drm_version struct are of type __kernel_size_t
and not unsigned long long.
BUG=chromium:837209
TEST=crosvm finds DRM device on kevin
Change-Id: If940b31cb730cbaa46ed781021cbe60189da9f65
Reviewed-on: https://chromium-review.googlesource.com/1064913
Commit-Ready: David Reveman <reveman@chromium.org>
Tested-by: David Reveman <reveman@chromium.org>
Reviewed-by: Zach Reizner <zachr@chromium.org>
This implements DMABuf allocation type in the virtio wayland
device.
We attempt to locate a supported DRM device prior to engaging
the device jail. If found, the DRM device is passed to the
wayland device code and used to serve DMABuf allocations.
DMABuf support can be disabled by not providing crosvm with
access to any DRM device nodes.
The guest is expected to handle the case when DMABuf allocation
fails and fall-back to standard shared memory.
This initial change uses DRM directly but is structured in a
way that would allow the allocator to be replaced by minigbm
with minimal effort.
BUG=chromium:837209
TEST=crosvm finds drm device and returns valid dmabufs to guest
Change-Id: Ic1fd776dfdfefae2d7b321d449273ef269e9cc62
Reviewed-on: https://chromium-review.googlesource.com/1034088
Commit-Ready: David Reveman <reveman@chromium.org>
Tested-by: David Reveman <reveman@chromium.org>
Reviewed-by: Zach Reizner <zachr@chromium.org>
These bindings are needed to allocate dmabufs that will be used for
accelerated rendering and zero-copy virtio-wayland support.
TEST=cargo test -p gpu_buffer
BUG=chromium:837073
Change-Id: I96d7bcdeaa1eda616a25fdcfedcbb734cd585ae7
Reviewed-on: https://chromium-review.googlesource.com/1029410
Commit-Ready: David Reveman <reveman@chromium.org>
Tested-by: Zach Reizner <zachr@chromium.org>
Reviewed-by: Zach Reizner <zachr@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>
