| // Copyright 2018 The Chromium OS Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| //! minigbm: implements swapchain allocation using ChromeOS's minigbm library. |
| //! |
| //! External code found at https://chromium.googlesource.com/chromiumos/platform/minigbm. |
| |
| #![cfg(feature = "minigbm")] |
| |
| use std::ffi::CStr; |
| use std::fs::File; |
| use std::io::{Seek, SeekFrom}; |
| use std::os::raw::c_char; |
| use std::rc::Rc; |
| |
| use base::{AsRawDescriptor, Error as SysError, FromRawDescriptor}; |
| |
| use crate::rutabaga_gralloc::formats::DrmFormat; |
| use crate::rutabaga_gralloc::gralloc::{Gralloc, ImageAllocationInfo, ImageMemoryRequirements}; |
| use crate::rutabaga_gralloc::minigbm_bindings::*; |
| use crate::rutabaga_gralloc::rendernode; |
| use crate::rutabaga_utils::*; |
| |
| struct MinigbmDeviceInner { |
| _fd: File, |
| gbm: *mut gbm_device, |
| } |
| |
| impl Drop for MinigbmDeviceInner { |
| fn drop(&mut self) { |
| // Safe because MinigbmDeviceInner is only constructed with a valid minigbm_device. |
| unsafe { |
| gbm_device_destroy(self.gbm); |
| } |
| } |
| } |
| |
| /// A device capable of allocating `MinigbmBuffer`. |
| #[derive(Clone)] |
| pub struct MinigbmDevice { |
| minigbm_device: Rc<MinigbmDeviceInner>, |
| last_buffer: Option<Rc<MinigbmBuffer>>, |
| device_name: &'static str, |
| } |
| |
| impl MinigbmDevice { |
| /// Returns a new `MinigbmDevice` if there is a rendernode in `/dev/dri/` that is accepted by |
| /// the minigbm library. |
| pub fn init() -> RutabagaResult<Box<dyn Gralloc>> { |
| let undesired: &[&str] = &["vgem", "pvr"]; |
| let fd = rendernode::open_device(undesired)?; |
| |
| // gbm_create_device is safe to call with a valid fd, and we check that a valid one is |
| // returned. If the fd does not refer to a DRM device, gbm_create_device will reject it. |
| let gbm = unsafe { gbm_create_device(fd.as_raw_descriptor()) }; |
| if gbm.is_null() { |
| return Err(RutabagaError::SysError(SysError::last())); |
| } |
| |
| // Safe because a valid minigbm device has a statically allocated string associated with |
| // it, which is valid for the lifetime of the process. |
| let backend_name: *const c_char = unsafe { gbm_device_get_backend_name(gbm) }; |
| let c_str: &CStr = unsafe { CStr::from_ptr(backend_name) }; |
| let device_name: &str = c_str.to_str()?; |
| |
| Ok(Box::new(MinigbmDevice { |
| minigbm_device: Rc::new(MinigbmDeviceInner { _fd: fd, gbm }), |
| last_buffer: None, |
| device_name, |
| })) |
| } |
| } |
| |
| impl Gralloc for MinigbmDevice { |
| fn supports_external_gpu_memory(&self) -> bool { |
| true |
| } |
| |
| fn supports_dmabuf(&self) -> bool { |
| true |
| } |
| |
| fn get_image_memory_requirements( |
| &mut self, |
| info: ImageAllocationInfo, |
| ) -> RutabagaResult<ImageMemoryRequirements> { |
| let bo = unsafe { |
| gbm_bo_create( |
| self.minigbm_device.gbm, |
| info.width, |
| info.height, |
| info.drm_format.0, |
| info.flags.0, |
| ) |
| }; |
| if bo.is_null() { |
| return Err(RutabagaError::SysError(SysError::last())); |
| } |
| |
| let mut reqs: ImageMemoryRequirements = Default::default(); |
| let gbm_buffer = MinigbmBuffer(bo, self.clone()); |
| |
| // Intel GPUs typically only use cached memory buffers. This will change with dGPUs, but |
| // perhaps minigbm will be deprecated by then. Other display drivers (rockchip, mediatek, |
| // amdgpu) typically use write combine memory. We can also consider use flags too if this |
| // heuristic proves insufficient. |
| if self.device_name == "i915" { |
| reqs.map_info = RUTABAGA_MAP_CACHE_CACHED; |
| } else { |
| reqs.map_info = RUTABAGA_MAP_CACHE_WC; |
| } |
| |
| reqs.modifier = gbm_buffer.format_modifier(); |
| for plane in 0..gbm_buffer.num_planes() { |
| reqs.strides[plane] = gbm_buffer.plane_stride(plane); |
| reqs.offsets[plane] = gbm_buffer.plane_offset(plane); |
| } |
| |
| let mut fd = gbm_buffer.export()?; |
| let size = fd.seek(SeekFrom::End(0))?; |
| |
| // minigbm does have the ability to query image requirements without allocating memory |
| // via the TEST_ALLOC flag. However, support has only been added in i915. Until this |
| // flag is supported everywhere, do the actual allocation here and stash it away. |
| if self.last_buffer.is_some() { |
| return Err(RutabagaError::AlreadyInUse); |
| } |
| |
| self.last_buffer = Some(Rc::new(gbm_buffer)); |
| reqs.info = info; |
| reqs.size = size; |
| Ok(reqs) |
| } |
| |
| fn allocate_memory(&mut self, reqs: ImageMemoryRequirements) -> RutabagaResult<RutabagaHandle> { |
| let last_buffer = self.last_buffer.take(); |
| if let Some(gbm_buffer) = last_buffer { |
| if gbm_buffer.width() != reqs.info.width |
| || gbm_buffer.height() != reqs.info.height |
| || gbm_buffer.format() != reqs.info.drm_format |
| { |
| return Err(RutabagaError::SpecViolation); |
| } |
| |
| let dmabuf = gbm_buffer.export()?.into(); |
| return Ok(RutabagaHandle { |
| os_handle: dmabuf, |
| handle_type: RUTABAGA_MEM_HANDLE_TYPE_DMABUF, |
| }); |
| } |
| |
| let bo = unsafe { |
| gbm_bo_create( |
| self.minigbm_device.gbm, |
| reqs.info.width, |
| reqs.info.height, |
| reqs.info.drm_format.0, |
| reqs.info.flags.0, |
| ) |
| }; |
| |
| if bo.is_null() { |
| return Err(RutabagaError::SysError(SysError::last())); |
| } |
| |
| let gbm_buffer = MinigbmBuffer(bo, self.clone()); |
| let dmabuf = gbm_buffer.export()?.into(); |
| Ok(RutabagaHandle { |
| os_handle: dmabuf, |
| handle_type: RUTABAGA_MEM_HANDLE_TYPE_DMABUF, |
| }) |
| } |
| } |
| |
| /// An allocation from a `MinigbmDevice`. |
| pub struct MinigbmBuffer(*mut gbm_bo, MinigbmDevice); |
| |
| impl MinigbmBuffer { |
| /// Width in pixels. |
| pub fn width(&self) -> u32 { |
| // This is always safe to call with a valid gbm_bo pointer. |
| unsafe { gbm_bo_get_width(self.0) } |
| } |
| |
| /// Height in pixels. |
| pub fn height(&self) -> u32 { |
| // This is always safe to call with a valid gbm_bo pointer. |
| unsafe { gbm_bo_get_height(self.0) } |
| } |
| |
| /// `DrmFormat` of the buffer. |
| pub fn format(&self) -> DrmFormat { |
| // This is always safe to call with a valid gbm_bo pointer. |
| unsafe { DrmFormat(gbm_bo_get_format(self.0)) } |
| } |
| |
| /// DrmFormat modifier flags for the buffer. |
| pub fn format_modifier(&self) -> u64 { |
| // This is always safe to call with a valid gbm_bo pointer. |
| unsafe { gbm_bo_get_modifier(self.0) } |
| } |
| |
| /// Number of planes present in this buffer. |
| pub fn num_planes(&self) -> usize { |
| // This is always safe to call with a valid gbm_bo pointer. |
| unsafe { gbm_bo_get_plane_count(self.0) as usize } |
| } |
| |
| /// Offset in bytes for the given plane. |
| pub fn plane_offset(&self, plane: usize) -> u32 { |
| // This is always safe to call with a valid gbm_bo pointer. |
| unsafe { gbm_bo_get_offset(self.0, plane) } |
| } |
| |
| /// Length in bytes of one row for the given plane. |
| pub fn plane_stride(&self, plane: usize) -> u32 { |
| // This is always safe to call with a valid gbm_bo pointer. |
| unsafe { gbm_bo_get_stride_for_plane(self.0, plane) } |
| } |
| |
| /// Exports a new dmabuf/prime file descriptor. |
| pub fn export(&self) -> RutabagaResult<File> { |
| // This is always safe to call with a valid gbm_bo pointer. |
| match unsafe { gbm_bo_get_fd(self.0) } { |
| fd if fd >= 0 => { |
| let dmabuf = unsafe { File::from_raw_descriptor(fd) }; |
| Ok(dmabuf) |
| } |
| ret => Err(RutabagaError::ComponentError(ret)), |
| } |
| } |
| } |
| |
| impl Drop for MinigbmBuffer { |
| fn drop(&mut self) { |
| // This is always safe to call with a valid gbm_bo pointer. |
| unsafe { gbm_bo_destroy(self.0) } |
| } |
| } |