diff options
| author | Dave Airlie <airlied@redhat.com> | 2025-05-21 05:49:31 +1000 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2025-05-21 05:49:31 +1000 |
| commit | c4f8ac095fc91084108ec21117eb9c1fff64725d (patch) | |
| tree | aebd07463aa88994b92c6653f53ef94d3fcc6710 | |
| parent | 7c1a9408ce5f34ded5a85db81cf80e0975901685 (diff) | |
| parent | 276c53c66e032c8e7cc0da63555f2742eb1afd69 (diff) | |
Merge tag 'nova-next-v6.16-2025-05-20' of https://gitlab.freedesktop.org/drm/nova into drm-next
Nova changes for v6.16
auxiliary:
- bus abstractions
- implementation for driver registration
- add sample driver
drm:
- implement __drm_dev_alloc()
- DRM core infrastructure Rust abstractions
- device, driver and registration
- DRM IOCTL
- DRM File
- GEM object
- IntoGEMObject rework
- generically implement AlwaysRefCounted through IntoGEMObject
- refactor unsound from_gem_obj() into as_ref()
- refactor into_gem_obj() into as_raw()
driver-core:
- merge topic/device-context-2025-04-17 from driver-core tree
- implement Devres::access()
- fix: doctest build under `!CONFIG_PCI`
- accessor for Device::parent()
- fix: conditionally expect `dead_code` for `parent()`
- impl TryFrom<&Device> bus devices (PCI, platform)
nova-core:
- remove completed Vec extentions from task list
- register auxiliary device for nova-drm
- derive useful traits for Chipset
- add missing GA100 chipset
- take &Device<Bound> in Gpu::new()
- infrastructure to generate register definitions
- fix register layout of NV_PMC_BOOT_0
- move Firmware into own (Rust) module
- fix: select AUXILIARY_BUS
nova-drm:
- initial driver skeleton (depends on drm and auxiliary bus
abstractions)
- fix: select AUXILIARY_BUS
Rust (dependencies):
- implement Opaque::zeroed()
- implement Revocable::try_access_with()
- implement Revocable::access()
From: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/aCxAf3RqQAXLDhAj@cassiopeiae
47 files changed, 2762 insertions, 197 deletions
diff --git a/Documentation/gpu/nova/core/todo.rst b/Documentation/gpu/nova/core/todo.rst index ca08377d3b73..8a459fc08812 100644 --- a/Documentation/gpu/nova/core/todo.rst +++ b/Documentation/gpu/nova/core/todo.rst @@ -102,7 +102,13 @@ Usage: let boot0 = Boot0::read(&bar); pr_info!("Revision: {}\n", boot0.revision()); +Note: a work-in-progress implementation currently resides in +`drivers/gpu/nova-core/regs/macros.rs` and is used in nova-core. It would be +nice to improve it (possibly using proc macros) and move it to the `kernel` +crate so it can be used by other components as well. + | Complexity: Advanced +| Contact: Alexandre Courbot Delay / Sleep abstractions -------------------------- @@ -190,16 +196,6 @@ Rust abstraction for debugfs APIs. | Reference: Export GSP log buffers | Complexity: Intermediate -Vec extensions --------------- - -Implement ``Vec::truncate`` and ``Vec::resize``. - -Currently this is used for some experimental code to parse the vBIOS. - -| Reference vBIOS support -| Complexity: Beginner - GPU (general) ============= diff --git a/MAINTAINERS b/MAINTAINERS index 9f3cb7ea2798..d063d711e092 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3880,6 +3880,9 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core.git F: Documentation/driver-api/auxiliary_bus.rst F: drivers/base/auxiliary.c F: include/linux/auxiliary_bus.h +F: rust/helpers/auxiliary.c +F: rust/kernel/auxiliary.rs +F: samples/rust/rust_driver_auxiliary.rs AUXILIARY DISPLAY DRIVERS M: Andy Shevchenko <andy@kernel.org> @@ -7607,6 +7610,18 @@ T: git https://gitlab.freedesktop.org/drm/nova.git nova-next F: Documentation/gpu/nova/ F: drivers/gpu/nova-core/ +DRM DRIVER FOR NVIDIA GPUS [RUST] +M: Danilo Krummrich <dakr@kernel.org> +L: nouveau@lists.freedesktop.org +S: Supported +Q: https://patchwork.freedesktop.org/project/nouveau/ +B: https://gitlab.freedesktop.org/drm/nova/-/issues +C: irc://irc.oftc.net/nouveau +T: git https://gitlab.freedesktop.org/drm/nova.git nova-next +F: Documentation/gpu/nova/ +F: drivers/gpu/drm/nova/ +F: include/uapi/drm/nova_drm.h + DRM DRIVER FOR OLIMEX LCD-OLINUXINO PANELS M: Stefan Mavrodiev <stefan@olimex.com> S: Maintained @@ -7820,6 +7835,7 @@ F: Documentation/devicetree/bindings/display/ F: Documentation/devicetree/bindings/gpu/ F: Documentation/gpu/ F: drivers/gpu/ +F: rust/kernel/drm/ F: include/drm/ F: include/linux/vga* F: include/uapi/drm/ @@ -7836,6 +7852,7 @@ F: Documentation/devicetree/bindings/gpu/ F: Documentation/gpu/ F: drivers/gpu/drm/ F: drivers/gpu/vga/ +F: rust/kernel/drm/ F: include/drm/drm F: include/linux/vga* F: include/uapi/drm/ diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index 9488fc01bca3..f094797f3b2b 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -274,6 +274,8 @@ source "drivers/gpu/drm/amd/amdgpu/Kconfig" source "drivers/gpu/drm/nouveau/Kconfig" +source "drivers/gpu/drm/nova/Kconfig" + source "drivers/gpu/drm/i915/Kconfig" source "drivers/gpu/drm/xe/Kconfig" diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index 70510620f29c..4199715670b1 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -177,6 +177,7 @@ obj-$(CONFIG_DRM_VMWGFX)+= vmwgfx/ obj-$(CONFIG_DRM_VGEM) += vgem/ obj-$(CONFIG_DRM_VKMS) += vkms/ obj-$(CONFIG_DRM_NOUVEAU) +=nouveau/ +obj-$(CONFIG_DRM_NOVA) += nova/ obj-$(CONFIG_DRM_EXYNOS) +=exynos/ obj-$(CONFIG_DRM_ROCKCHIP) +=rockchip/ obj-$(CONFIG_DRM_GMA500) += gma500/ diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c index 3dc7acd56b1d..4589ab4bb1ec 100644 --- a/drivers/gpu/drm/drm_drv.c +++ b/drivers/gpu/drm/drm_drv.c @@ -830,36 +830,62 @@ void *__devm_drm_dev_alloc(struct device *parent, EXPORT_SYMBOL(__devm_drm_dev_alloc); /** - * drm_dev_alloc - Allocate new DRM device - * @driver: DRM driver to allocate device for + * __drm_dev_alloc - Allocation of a &drm_device instance * @parent: Parent device object + * @driver: DRM driver + * @size: the size of the struct which contains struct drm_device + * @offset: the offset of the &drm_device within the container. * - * This is the deprecated version of devm_drm_dev_alloc(), which does not support - * subclassing through embedding the struct &drm_device in a driver private - * structure, and which does not support automatic cleanup through devres. + * This should *NOT* be by any drivers, but is a dedicated interface for the + * corresponding Rust abstraction. * - * RETURNS: - * Pointer to new DRM device, or ERR_PTR on failure. + * This is the same as devm_drm_dev_alloc(), but without the corresponding + * resource management through the parent device, but not the same as + * drm_dev_alloc(), since the latter is the deprecated version, which does not + * support subclassing. + * + * Returns: A pointer to new DRM device, or an ERR_PTR on failure. */ -struct drm_device *drm_dev_alloc(const struct drm_driver *driver, - struct device *parent) +void *__drm_dev_alloc(struct device *parent, + const struct drm_driver *driver, + size_t size, size_t offset) { - struct drm_device *dev; + void *container; + struct drm_device *drm; int ret; - dev = kzalloc(sizeof(*dev), GFP_KERNEL); - if (!dev) + container = kzalloc(size, GFP_KERNEL); + if (!container) return ERR_PTR(-ENOMEM); - ret = drm_dev_init(dev, driver, parent); + drm = container + offset; + ret = drm_dev_init(drm, driver, parent); if (ret) { - kfree(dev); + kfree(container); return ERR_PTR(ret); } + drmm_add_final_kfree(drm, container); - drmm_add_final_kfree(dev, dev); + return container; +} +EXPORT_SYMBOL(__drm_dev_alloc); - return dev; +/** + * drm_dev_alloc - Allocate new DRM device + * @driver: DRM driver to allocate device for + * @parent: Parent device object + * + * This is the deprecated version of devm_drm_dev_alloc(), which does not support + * subclassing through embedding the struct &drm_device in a driver private + * structure, and which does not support automatic cleanup through devres. + * + * RETURNS: + * Pointer to new DRM device, or ERR_PTR on failure. + */ +struct drm_device *drm_dev_alloc(const struct drm_driver *driver, + struct device *parent) +{ + return __drm_dev_alloc(parent, driver, sizeof(struct drm_device), 0); } EXPORT_SYMBOL(drm_dev_alloc); diff --git a/drivers/gpu/drm/nova/Kconfig b/drivers/gpu/drm/nova/Kconfig new file mode 100644 index 000000000000..cca6a3fea879 --- /dev/null +++ b/drivers/gpu/drm/nova/Kconfig @@ -0,0 +1,14 @@ +config DRM_NOVA + tristate "Nova DRM driver" + depends on DRM=y + depends on PCI + depends on RUST + select AUXILIARY_BUS + default n + help + Choose this if you want to build the Nova DRM driver for Nvidia + GSP-based GPUs. + + This driver is work in progress and may not be functional. + + If M is selected, the module will be called nova. diff --git a/drivers/gpu/drm/nova/Makefile b/drivers/gpu/drm/nova/Makefile new file mode 100644 index 000000000000..42019bff3173 --- /dev/null +++ b/drivers/gpu/drm/nova/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_DRM_NOVA) += nova.o diff --git a/drivers/gpu/drm/nova/driver.rs b/drivers/gpu/drm/nova/driver.rs new file mode 100644 index 000000000000..b28b2e05cc15 --- /dev/null +++ b/drivers/gpu/drm/nova/driver.rs @@ -0,0 +1,69 @@ +// SPDX-License-Identifier: GPL-2.0 + +use kernel::{auxiliary, c_str, device::Core, drm, drm::gem, drm::ioctl, prelude::*, types::ARef}; + +use crate::file::File; +use crate::gem::NovaObject; + +pub(crate) struct NovaDriver { + #[expect(unused)] + drm: ARef<drm::Device<Self>>, +} + +/// Convienence type alias for the DRM device type for this driver +pub(crate) type NovaDevice = drm::Device<NovaDriver>; + +#[pin_data] +pub(crate) struct NovaData { + pub(crate) adev: ARef<auxiliary::Device>, +} + +const INFO: drm::DriverInfo = drm::DriverInfo { + major: 0, + minor: 0, + patchlevel: 0, + name: c_str!("nova"), + desc: c_str!("Nvidia Graphics"), +}; + +const NOVA_CORE_MODULE_NAME: &CStr = c_str!("NovaCore"); +const AUXILIARY_NAME: &CStr = c_str!("nova-drm"); + +kernel::auxiliary_device_table!( + AUX_TABLE, + MODULE_AUX_TABLE, + <NovaDriver as auxiliary::Driver>::IdInfo, + [( + auxiliary::DeviceId::new(NOVA_CORE_MODULE_NAME, AUXILIARY_NAME), + () + )] +); + +impl auxiliary::Driver for NovaDriver { + type IdInfo = (); + const ID_TABLE: auxiliary::IdTable<Self::IdInfo> = &AUX_TABLE; + + fn probe(adev: &auxiliary::Device<Core>, _info: &Self::IdInfo) -> Result<Pin<KBox<Self>>> { + let data = try_pin_init!(NovaData { adev: adev.into() }); + + let drm = drm::Device::<Self>::new(adev.as_ref(), data)?; + drm::Registration::new_foreign_owned(&drm, adev.as_ref(), 0)?; + + Ok(KBox::new(Self { drm }, GFP_KERNEL)?.into()) + } +} + +#[vtable] +impl drm::Driver for NovaDriver { + type Data = NovaData; + type File = File; + type Object = gem::Object<NovaObject>; + + const INFO: drm::DriverInfo = INFO; + + kernel::declare_drm_ioctls! { + (NOVA_GETPARAM, drm_nova_getparam, ioctl::RENDER_ALLOW, File::get_param), + (NOVA_GEM_CREATE, drm_nova_gem_create, ioctl::AUTH | ioctl::RENDER_ALLOW, File::gem_create), + (NOVA_GEM_INFO, drm_nova_gem_info, ioctl::AUTH | ioctl::RENDER_ALLOW, File::gem_info), + } +} diff --git a/drivers/gpu/drm/nova/file.rs b/drivers/gpu/drm/nova/file.rs new file mode 100644 index 000000000000..7e59a34b830d --- /dev/null +++ b/drivers/gpu/drm/nova/file.rs @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0 + +use crate::driver::{NovaDevice, NovaDriver}; +use crate::gem::NovaObject; +use crate::uapi::{GemCreate, GemInfo, Getparam}; +use kernel::{ + alloc::flags::*, + drm::{self, gem::BaseObject}, + pci, + prelude::*, + types::Opaque, + uapi, +}; + +pub(crate) struct File; + +impl drm::file::DriverFile for File { + type Driver = NovaDriver; + + fn open(_dev: &NovaDevice) -> Result<Pin<KBox<Self>>> { + Ok(KBox::new(Self, GFP_KERNEL)?.into()) + } +} + +impl File { + /// IOCTL: get_param: Query GPU / driver metadata. + pub(crate) fn get_param( + dev: &NovaDevice, + getparam: &Opaque<uapi::drm_nova_getparam>, + _file: &drm::File<File>, + ) -> Result<u32> { + let adev = &dev.adev; + let parent = adev.parent().ok_or(ENOENT)?; + let pdev: &pci::Device = parent.try_into()?; + let getparam: &Getparam = getparam.into(); + + let value = match getparam.param() as u32 { + uapi::NOVA_GETPARAM_VRAM_BAR_SIZE => pdev.resource_len(1)?, + _ => return Err(EINVAL), + }; + + getparam.set_value(value); + + Ok(0) + } + + /// IOCTL: gem_create: Create a new DRM GEM object. + pub(crate) fn gem_create( + dev: &NovaDevice, + req: &Opaque<uapi::drm_nova_gem_create>, + file: &drm::File<File>, + ) -> Result<u32> { + let req: &GemCreate = req.into(); + let obj = NovaObject::new(dev, req.size().try_into()?)?; + + req.set_handle(obj.create_handle(file)?); + + Ok(0) + } + + /// IOCTL: gem_info: Query GEM metadata. + pub(crate) fn gem_info( + _dev: &NovaDevice, + req: &Opaque<uapi::drm_nova_gem_info>, + file: &drm::File<File>, + ) -> Result<u32> { + let req: &GemInfo = req.into(); + let bo = NovaObject::lookup_handle(file, req.handle())?; + + req.set_size(bo.size().try_into()?); + + Ok(0) + } +} diff --git a/drivers/gpu/drm/nova/gem.rs b/drivers/gpu/drm/nova/gem.rs new file mode 100644 index 000000000000..33b62d21400c --- /dev/null +++ b/drivers/gpu/drm/nova/gem.rs @@ -0,0 +1,49 @@ +// SPDX-License-Identifier: GPL-2.0 + +use kernel::{ + drm, + drm::{gem, gem::BaseObject}, + prelude::*, + types::ARef, +}; + +use crate::{ + driver::{NovaDevice, NovaDriver}, + file::File, +}; + +/// GEM Object inner driver data +#[pin_data] +pub(crate) struct NovaObject {} + +impl gem::BaseDriverObject<gem::Object<NovaObject>> for NovaObject { + fn new(_dev: &NovaDevice, _size: usize) -> impl PinInit<Self, Error> { + try_pin_init!(NovaObject {}) + } +} + +impl gem::DriverObject for NovaObject { + type Driver = NovaDriver; +} + +impl NovaObject { + /// Create a new DRM GEM object. + pub(crate) fn new(dev: &NovaDevice, size: usize) -> Result<ARef<gem::Object<Self>>> { + let aligned_size = size.next_multiple_of(1 << 12); + + if size == 0 || size > aligned_size { + return Err(EINVAL); + } + + gem::Object::new(dev, aligned_size) + } + + /// Look up a GEM object handle for a `File` and return an `ObjectRef` for it. + #[inline] + pub(crate) fn lookup_handle( + file: &drm::File<File>, + handle: u32, + ) -> Result<ARef<gem::Object<Self>>> { + gem::Object::lookup_handle(file, handle) + } +} diff --git a/drivers/gpu/drm/nova/nova.rs b/drivers/gpu/drm/nova/nova.rs new file mode 100644 index 000000000000..902876aa14d1 --- /dev/null +++ b/drivers/gpu/drm/nova/nova.rs @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! Nova DRM Driver + +mod driver; +mod file; +mod gem; +mod uapi; + +use crate::driver::NovaDriver; + +kernel::module_auxiliary_driver! { + type: NovaDriver, + name: "Nova", + author: "Danilo Krummrich", + description: "Nova GPU driver", + license: "GPL v2", +} diff --git a/drivers/gpu/drm/nova/uapi.rs b/drivers/gpu/drm/nova/uapi.rs new file mode 100644 index 000000000000..eb228a58d423 --- /dev/null +++ b/drivers/gpu/drm/nova/uapi.rs @@ -0,0 +1,61 @@ +// SPDX-License-Identifier: GPL-2.0 + +use kernel::uapi; + +// TODO Work out some common infrastructure to avoid boilerplate code for uAPI abstractions. + +macro_rules! define_uapi_abstraction { + ($name:ident <= $inner:ty) => { + #[repr(transparent)] + pub struct $name(::kernel::types::Opaque<$inner>); + + impl ::core::convert::From<&::kernel::types::Opaque<$inner>> for &$name { + fn from(value: &::kernel::types::Opaque<$inner>) -> Self { + // SAFETY: `Self` is a transparent wrapper of `$inner`. + unsafe { ::core::mem::transmute(value) } + } + } + }; +} + +define_uapi_abstraction!(Getparam <= uapi::drm_nova_getparam); + +impl Getparam { + pub fn param(&self) -> u64 { + // SAFETY: `self.get()` is a valid pointer to a `struct drm_nova_getparam`. + unsafe { (*self.0.get()).param } + } + + pub fn set_value(&self, v: u64) { + // SAFETY: `self.get()` is a valid pointer to a `struct drm_nova_getparam`. + unsafe { (*self.0.get()).value = v }; + } +} + +define_uapi_abstraction!(GemCreate <= uapi::drm_nova_gem_create); + +impl GemCreate { + pub fn size(&self) -> u64 { + // SAFETY: `self.get()` is a valid pointer to a `struct drm_nova_gem_create`. + unsafe { (*self.0.get()).size } + } + + pub fn set_handle(&self, handle: u32) { + // SAFETY: `self.get()` is a valid pointer to a `struct drm_nova_gem_create`. + unsafe { (*self.0.get()).handle = handle }; + } +} + +define_uapi_abstraction!(GemInfo <= uapi::drm_nova_gem_info); + +impl GemInfo { + pub fn handle(&self) -> u32 { + // SAFETY: `self.get()` is a valid pointer to a `struct drm_nova_gem_info`. + unsafe { (*self.0.get()).handle } + } + + pub fn set_size(&self, size: u64) { + // SAFETY: `self.get()` is a valid pointer to a `struct drm_nova_gem_info`. + unsafe { (*self.0.get()).size = size }; + } +} diff --git a/drivers/gpu/nova-core/Kconfig b/drivers/gpu/nova-core/Kconfig index ad0c06756516..8726d80d6ba4 100644 --- a/drivers/gpu/nova-core/Kconfig +++ b/drivers/gpu/nova-core/Kconfig @@ -3,6 +3,7 @@ config NOVA_CORE depends on PCI depends on RUST depends on RUST_FW_LOADER_ABSTRACTIONS + select AUXILIARY_BUS default n help Choose this if you want to build the Nova Core driver for Nvidia diff --git a/drivers/gpu/nova-core/driver.rs b/drivers/gpu/nova-core/driver.rs index a08fb6599267..8c86101c26cb 100644 --- a/drivers/gpu/nova-core/driver.rs +++ b/drivers/gpu/nova-core/driver.rs @@ -1,6 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 -use kernel::{bindings, c_str, device::Core, pci, prelude::*}; +use kernel::{auxiliary, bindings, c_str, device::Core, pci, prelude::*}; use crate::gpu::Gpu; @@ -8,6 +8,7 @@ use crate::gpu::Gpu; pub(crate) struct NovaCore { #[pin] pub(crate) gpu: Gpu, + _reg: auxiliary::Registration, } const BAR0_SIZE: usize = 8; @@ -38,6 +39,12 @@ impl pci::Driver for NovaCore { let this = KBox::pin_init( try_pin_init!(Self { gpu <- Gpu::new(pdev, bar)?, + _reg: auxiliary::Registration::new( + pdev.as_ref(), + c_str!("nova-drm"), + 0, // TODO: Once it lands, use XArray; for now we don't use the ID. + crate::MODULE_NAME + )?, }), GFP_KERNEL, )?; diff --git a/drivers/gpu/nova-core/firmware.rs b/drivers/gpu/nova-core/firmware.rs index 6e6361c59ca1..4b8a38358a4f 100644 --- a/drivers/gpu/nova-core/firmware.rs +++ b/drivers/gpu/nova-core/firmware.rs @@ -1,13 +1,49 @@ // SPDX-License-Identifier: GPL-2.0 -use crate::gpu; +//! Contains structures and functions dedicated to the parsing, building and patching of firmwares +//! to be loaded into a given execution unit. + +use kernel::device; use kernel::firmware; +use kernel::prelude::*; +use kernel::str::CString; + +use crate::gpu; +use crate::gpu::Chipset; + +pub(crate) const FIRMWARE_VERSION: &str = "535.113.01"; + +/// Structure encapsulating the firmware blobs required for the GPU to operate. +#[expect(dead_code)] +pub(crate) struct Firmware { + booter_load: firmware::Firmware, + booter_unload: firmware::Firmware, + bootloader: firmware::Firmware, + gsp: firmware::Firmware, +} + +impl Firmware { + pub(crate) fn new(dev: &device::Device, chipset: Chipset, ver: &str) -> Result<Firmware> { + let mut chip_name = CString::try_from_fmt(fmt!("{}", chipset))?; + chip_name.make_ascii_lowercase(); + + let request = |name_| { + CString::try_from_fmt(fmt!("nvidia/{}/gsp/{}-{}.bin", &*chip_name, name_, ver)) + .and_then(|path| firmware::Firmware::request(&path, dev)) + }; + + Ok(Firmware { + booter_load: request("booter_load")?, + booter_unload: request("booter_unload")?, + bootloader: request("bootloader")?, + gsp: request("gsp")?, + }) + } +} pub(crate) struct ModInfoBuilder<const N: usize>(firmware::ModInfoBuilder<N>); impl<const N: usize> ModInfoBuilder<N> { - const VERSION: &'static str = "535.113.01"; - const fn make_entry_file(self, chipset: &str, fw: &str) -> Self { ModInfoBuilder( self.0 @@ -17,7 +53,7 @@ impl<const N: usize> ModInfoBuilder<N> { .push("/gsp/") .push(fw) .push("-") - .push(Self::VERSION) + .push(FIRMWARE_VERSION) .push(".bin"), ) } diff --git a/drivers/gpu/nova-core/gpu.rs b/drivers/gpu/nova-core/gpu.rs index 17c9660da450..99c6796e73e9 100644 --- a/drivers/gpu/nova-core/gpu.rs +++ b/drivers/gpu/nova-core/gpu.rs @@ -1,10 +1,9 @@ // SPDX-License-Identifier: GPL-2.0 -use kernel::{ - device, devres::Devres, error::code::*, firmware, fmt, pci, prelude::*, str::CString, -}; +use kernel::{device, devres::Devres, error::code::*, pci, prelude::*}; use crate::driver::Bar0; +use crate::firmware::{Firmware, FIRMWARE_VERSION}; use crate::regs; use crate::util; use core::fmt; @@ -13,7 +12,7 @@ macro_rules! define_chipset { ({ $($variant:ident = $value:expr),* $(,)* }) => { /// Enum representation of the GPU chipset. - #[derive(fmt::Debug)] + #[derive(fmt::Debug, Copy, Clone, PartialOrd, Ord, PartialEq, Eq)] pub(crate) enum Chipset { $($variant = $value),*, } @@ -54,6 +53,7 @@ define_chipset!({ TU117 = 0x167, TU116 = 0x168, // Ampere + GA100 = 0x170, GA102 = 0x172, GA103 = 0x173, GA104 = 0x174, @@ -73,7 +73,7 @@ impl Chipset { Self::TU102 | Self::TU104 | Self::TU106 | Self::TU117 | Self::TU116 => { Architecture::Turing } - Self::GA102 | Self::GA103 | Self::GA104 | Self::GA106 | Self::GA107 => { + Self::GA100 | Self::GA102 | Self::GA103 | Self::GA104 | Self::GA106 | Self::GA107 => { Architecture::Ampere } Self::AD102 | Self::AD103 | Self::AD104 | Self::AD106 | Self::AD107 => { @@ -100,9 +100,22 @@ impl fmt::Display for Chipset { /// Enum representation of the GPU generation. #[derive(fmt::Debug)] pub(crate) enum Architecture { - Turing, - Ampere, - Ada, + Turing = 0x16, + Ampere = 0x17, + Ada = 0x19, +} + +impl TryFrom<u8> for Architecture { + type Error = Error; + + fn try_from(value: u8) -> Result<Self> { + match value { + 0x16 => Ok(Self::Turing), + 0x17 => Ok(Self::Ampere), + 0x19 => Ok(Self::Ada), + _ => Err(ENODEV), + } + } } pub(crate) struct Revision { @@ -111,10 +124,10 @@ pub(crate) struct Revision { } impl Revision { - fn from_boot0(boot0: regs::Boot0) -> Self { + fn from_boot0(boot0: regs::NV_PMC_BOOT_0) -> Self { Self { - major: boot0.major_rev(), - minor: boot0.minor_rev(), + major: boot0.major_revision(), + minor: boot0.minor_revision(), } } } @@ -133,45 +146,16 @@ pub(crate) struct Spec { } impl Spec { - fn new(bar: &Devres<Bar0>) -> Result<Spec> { - let bar = bar.try_access().ok_or(ENXIO)?; - let boot0 = regs::Boot0::read(&bar); + fn new(bar: &Bar0) -> Result<Spec> { + let boot0 = regs::NV_PMC_BOOT_0::read(bar); Ok(Self { - chipset: boot0.chipset().try_into()?, + chipset: boot0.chipset()?, revision: Revision::from_boot0(boot0), }) } } -/// Structure encapsulating the firmware blobs required for the GPU to operate. -#[expect(dead_code)] -pub(crate) struct Firmware { - booter_load: firmware::Firmware, - booter_unload: firmware::Firmware, - bootloader: firmware::Firmware, - gsp: firmware::Firmware, -} - -impl Firmware { - fn new(dev: &device::Device, spec: &Spec, ver: &str) -> Result<Firmware> { - let mut chip_name = CString::try_from_fmt(fmt!("{}", spec.chipset))?; - chip_name.make_ascii_lowercase(); - - let request = |name_| { - CString::try_from_fmt(fmt!("nvidia/{}/gsp/{}-{}.bin", &*chip_name, name_, ver)) - .and_then(|path| firmware::Firmware::request(&path, dev)) - }; - - Ok(Firmware { - booter_load: request("booter_load")?, - booter_unload: request("booter_unload")?, - bootloader: request("bootloader")?, - gsp: request("gsp")?, - }) - } -} - /// Structure holding the resources required to operate the GPU. #[pin_data] pub(crate) struct Gpu { @@ -182,9 +166,13 @@ pub(crate) struct Gpu { } impl Gpu { - pub(crate) fn new(pdev: &pci::Device, bar: Devres<Bar0>) -> Result<impl PinInit<Self>> { - let spec = Spec::new(&bar)?; - let fw = Firmware::new(pdev.as_ref(), &spec, "535.113.01")?; + pub(crate) fn new( + pdev: &pci::Device<device::Bound>, + devres_bar: Devres<Bar0>, + ) -> Result<impl PinInit<Self>> { + let bar = devres_bar.access(pdev.as_ref())?; + let spec = Spec::new(bar)?; + let fw = Firmware::new(pdev.as_ref(), spec.chipset, FIRMWARE_VERSION)?; dev_info!( pdev.as_ref(), @@ -194,6 +182,10 @@ impl Gpu { spec.revision ); - Ok(pin_init!(Self { spec, bar, fw })) + Ok(pin_init!(Self { + spec, + bar: devres_bar, + fw + })) } } diff --git a/drivers/gpu/nova-core/nova_core.rs b/drivers/gpu/nova-core/nova_core.rs index a91cd924054b..618632f0abcc 100644 --- a/drivers/gpu/nova-core/nova_core.rs +++ b/drivers/gpu/nova-core/nova_core.rs @@ -8,6 +8,8 @@ mod gpu; mod regs; mod util; +pub(crate) const MODULE_NAME: &kernel::str::CStr = <LocalModule as kernel::ModuleMetadata>::NAME; + kernel::module_pci_driver! { type: driver::NovaCore, name: "NovaCore", diff --git a/drivers/gpu/nova-core/regs.rs b/drivers/gpu/nova-core/regs.rs index b1a25b86ef17..5a1273230306 100644 --- a/drivers/gpu/nova-core/regs.rs +++ b/drivers/gpu/nova-core/regs.rs @@ -1,55 +1,39 @@ // SPDX-License-Identifier: GPL-2.0 -use crate::driver::Bar0; - -// TODO -// -// Create register definitions via generic macros. See task "Generic register -// abstraction" in Documentation/gpu/nova/core/todo.rst. - -const BOOT0_OFFSET: usize = 0x00000000; - -// 3:0 - chipset minor revision -const BOOT0_MINOR_REV_SHIFT: u8 = 0; -const BOOT0_MINOR_REV_MASK: u32 = 0x0000000f; - -// 7:4 - chipset major revision -const BOOT0_MAJOR_REV_SHIFT: u8 = 4; -const BOOT0_MAJOR_REV_MASK: u32 = 0x000000f0; - -// 23:20 - chipset implementation Identifier (depends on architecture) -const BOOT0_IMPL_SHIFT: u8 = 20; -const BOOT0_IMPL_MASK: u32 = 0x00f00000; - -// 28:24 - chipset architecture identifier -const BOOT0_ARCH_MASK: u32 = 0x1f000000; - -// 28:20 - chipset identifier (virtual register field combining BOOT0_IMPL and -// BOOT0_ARCH) -const BOOT0_CHIPSET_SHIFT: u8 = BOOT0_IMPL_SHIFT; -const BOOT0_CHIPSET_MASK: u32 = BOOT0_IMPL_MASK | BOOT0_ARCH_MASK; - -#[derive(Copy, Clone)] -pub(crate) struct Boot0(u32); - -impl Boot0 { - #[inline] - pub(crate) fn read(bar: &Bar0) -> Self { - Self(bar.read32(BOOT0_OFFSET)) - } - - #[inline] - pub(crate) fn chipset(&self) -> u32 { - (self.0 & BOOT0_CHIPSET_MASK) >> BOOT0_CHIPSET_SHIFT - } - - #[inline] - pub(crate) fn minor_rev(&self) -> u8 { - ((self.0 & BOOT0_MINOR_REV_MASK) >> BOOT0_MINOR_REV_SHIFT) as u8 +// Required to retain the original register names used by OpenRM, which are all capital snake case +// but are mapped to types. +#![allow(non_camel_case_types)] + +#[macro_use] +mod macros; + +use crate::gpu::{Architecture, Chipset}; +use kernel::prelude::*; + +/* PMC */ + +register!(NV_PMC_BOOT_0 @ 0x00000000, "Basic revision information about the GPU" { + 3:0 minor_revision as u8, "Minor revision of the chip"; + 7:4 major_revision as u8, "Major revision of the chip"; + 8:8 architecture_1 as u8, "MSB of the architecture"; + 23:20 implementation as u8, "Implementation version of the architecture"; + 28:24 architecture_0 as u8, "Lower bits of the architecture"; +}); + +impl NV_PMC_BOOT_0 { + /// Combines `architecture_0` and `architecture_1` to obtain the architecture of the chip. + pub(crate) fn architecture(self) -> Result<Architecture> { + Architecture::try_from( + self.architecture_0() | (self.architecture_1() << Self::ARCHITECTURE_0.len()), + ) } - #[inline] - pub(crate) fn major_rev(&self) -> u8 { - ((self.0 & BOOT0_MAJOR_REV_MASK) >> BOOT0_MAJOR_REV_SHIFT) as u8 + /// Combines `architecture` and `implementation` to obtain a code unique to the chipset. + pub(crate) fn chipset(self) -> Result<Chipset> { + self.architecture() + .map(|arch| { + ((arch as u32) << Self::IMPLEMENTATION.len()) | self.implementation() as u32 + }) + .and_then(Chipset::try_from) } } diff --git a/drivers/gpu/nova-core/regs/macros.rs b/drivers/gpu/nova-core/regs/macros.rs new file mode 100644 index 000000000000..7ecc70efb3cd --- /dev/null +++ b/drivers/gpu/nova-core/regs/macros.rs @@ -0,0 +1,380 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! Macro to define register layout and accessors. +//! +//! A single register typically includes several fields, which are accessed through a combination +//! of bit-shift and mask operations that introduce a class of potential mistakes, notably because +//! not all possible field values are necessarily valid. +//! +//! The macro in this module allow to define, using an intruitive and readable syntax, a dedicated +//! type for each register with its own field accessors that can return an error is a field's value +//! is invalid. + +/// Defines a dedicated type for a register with an absolute offset, alongside with getter and +/// setter methods for its fields and methods to read and write it from an `Io` region. +/// +/// Example: +/// +/// ```no_run +/// register!(BOOT_0 @ 0x00000100, "Basic revision information about the GPU" { +/// 3:0 minor_revision as u8, "Minor revision of the chip"; +/// 7:4 major_revision as u8, "Major revision of the chip"; +/// 28:20 chipset as u32 ?=> Chipset, "Chipset model"; +/// }); +/// ``` +/// +/// This defines a `BOOT_0` type which can be read or written from offset `0x100` of an `Io` +/// region. It is composed of 3 fields, for instance `minor_revision` is made of the 4 less +/// significant bits of the register. Each field can be accessed and modified using accessor +/// methods: +/// +/// ```no_run +/// // Read from the register's defined offset (0x100). +/// let boot0 = BOOT_0::read(&bar); +/// pr_info!("chip revision: {}.{}", boot0.major_revision(), boot0.minor_revision()); +/// +/// // `Chipset::try_from` will be called with the value of the field and returns an error if the +/// // value is invalid. +/// let chipset = boot0.chipset()?; +/// +/// // Update some fields and write the value back. +/// boot0.set_major_revision(3).set_minor_revision(10).write(&bar); +/// +/// // Or just read and update the register in a single step: +/// BOOT_0::alter(&bar, |r| r.set_major_revision(3).set_minor_revision(10)); +/// ``` +/// +/// Fields can be defined as follows: +/// +/// - `as <type>` simply returns the field value casted as the requested integer type, typically +/// `u32`, `u16`, `u8` or `bool`. Note that `bool` fields must have a range of 1 bit. +/// - `as <type> => <into_type>` calls `<into_type>`'s `From::<<type>>` implementation and returns +/// the result. +/// - `as <type> ?=> <try_into_type>` calls `<try_into_type>`'s `TryFrom::<<type>>` implementation +/// and returns the result. This is useful on fields for which not all values are value. +/// +/// The documentation strings are optional. If present, they will be added to the type's +/// definition, or the field getter and setter methods they are attached to. +/// +/// Putting a `+` before the address of the register makes it relative to a base: the `read` and +/// `write` methods take a `base` argument that is added to the specified address before access, +/// and `try_read` and `try_write` methods are also created, allowing access with offsets unknown +/// at compile-time: +/// +/// ```no_run +/// register!(CPU_CTL @ +0x0000010, "CPU core control" { +/// 0:0 start as bool, "Start the CPU core"; +/// }); +/// +/// // Flip the `start` switch for the CPU core which base address is at `CPU_BASE`. +/// let cpuctl = CPU_CTL::read(&bar, CPU_BASE); +/// pr_info!("CPU CTL: {:#x}", cpuctl); +/// cpuctl.set_start(true).write(&bar, CPU_BASE); +/// ``` +macro_rules! register { + // Creates a register at a fixed offset of the MMIO space. + ( + $name:ident @ $offset:literal $(, $comment:literal)? { + $($fields:tt)* + } + ) => { + register!(@common $name $(, $comment)?); + register!(@field_accessors $name { $($fields)* }); + register!(@io $name @ $offset); + }; + + // Creates a register at a relative offset from a base address. + ( + $name:ident @ + $offset:literal $(, $comment:literal)? { + $($fields:tt)* + } + ) => { + register!(@common $name $(, $comment)?); + register!(@field_accessors $name { $($fields)* }); + register!(@io$name @ + $offset); + }; + + // Defines the wrapper `$name` type, as well as its relevant implementations (`Debug`, `BitOr`, + // and conversion to regular `u32`). + (@common $name:ident $(, $comment:literal)?) => { + $( + #[doc=$comment] + )? + #[repr(transparent)] + #[derive(Clone, Copy, Default)] + pub(crate) struct $name(u32); + + // TODO: display the raw hex value, then the value of all the fields. This requires + // matching the fields, which will complexify the syntax considerably... + impl ::core::fmt::Debug for $name { + fn fmt(&self, f: &mut ::core::fmt::Formatter<'_>) -> ::core::fmt::Result { + f.debug_tuple(stringify!($name)) + .field(&format_args!("0x{0:x}", &self.0)) + .finish() + } + } + + impl core::ops::BitOr for $name { + type Output = Self; + + fn bitor(self, rhs: Self) -> Self::Output { + Self(self.0 | rhs.0) + } + } + + impl ::core::convert::From<$name> for u32 { + fn from(reg: $name) -> u32 { + reg.0 + } + } + }; + + // Defines all the field getter/methods methods for `$name`. + ( + @field_accessors $name:ident { + $($hi:tt:$lo:tt $field:ident as $type:tt + $(?=> $try_into_type:ty)? + $(=> $into_type:ty)? + $(, $comment:literal)? + ; + )* + } + ) => { + $( + register!(@check_field_bounds $hi:$lo $field as $type); + )* + + #[allow(dead_code)] + impl $name { + $( + register!(@field_accessor $name $hi:$lo $field as $type + $(?=> $try_into_type)? + $(=> $into_type)? + $(, $comment)? + ; + ); + )* + } + }; + + // Boolean fields must have `$hi == $lo`. + (@check_field_bounds $hi:tt:$lo:tt $field:ident as bool) => { + #[allow(clippy::eq_op)] + const _: () = { + kernel::build_assert!( + $hi == $lo, + concat!("boolean field `", stringify!($field), "` covers more than one bit") + ); + }; + }; + + // Non-boolean fields must have `$hi >= $lo`. + (@check_field_bounds $hi:tt:$lo:tt $field:ident as $type:tt) => { + #[allow(clippy::eq_op)] + const _: () = { + kernel::build_assert!( + $hi >= $lo, + concat!("field `", stringify!($field), "`'s MSB is smaller than its LSB") + ); + }; + }; + + // Catches fields defined as `bool` and convert them into a boolean value. + ( + @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as bool => $into_type:ty + $(, $comment:literal)?; + ) => { + register!( + @leaf_accessor $name $hi:$lo $field as bool + { |f| <$into_type>::from(if f != 0 { true } else { false }) } + $into_type => $into_type $(, $comment)?; + ); + }; + + // Shortcut for fields defined as `bool` without the `=>` syntax. + ( + @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as bool $(, $comment:literal)?; + ) => { + register!(@field_accessor $name $hi:$lo $field as bool => bool $(, $comment)?;); + }; + + // Catches the `?=>` syntax for non-boolean fields. + ( + @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as $type:tt ?=> $try_into_type:ty + $(, $comment:literal)?; + ) => { + register!(@leaf_accessor $name $hi:$lo $field as $type + { |f| <$try_into_type>::try_from(f as $type) } $try_into_type => + ::core::result::Result< + $try_into_type, + <$try_into_type as ::core::convert::TryFrom<$type>>::Error + > + $(, $comment)?;); + }; + + // Catches the `=>` syntax for non-boolean fields. + ( + @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as $type:tt => $into_type:ty + $(, $comment:literal)?; + ) => { + register!(@leaf_accessor $name $hi:$lo $field as $type + { |f| <$into_type>::from(f as $type) } $into_type => $into_type $(, $comment)?;); + }; + + // Shortcut for fields defined as non-`bool` without the `=>` or `?=>` syntax. + ( + @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as $type:tt + $(, $comment:literal)?; + ) => { + register!(@field_accessor $name $hi:$lo $field as $type => $type $(, $comment)?;); + }; + + // Generates the accessor methods for a single field. + ( + @leaf_accessor $name:ident $hi:tt:$lo:tt $field:ident as $type:ty + { $process:expr } $to_type:ty => $res_type:ty $(, $comment:literal)?; + ) => { + kernel::macros::paste!( + const [<$field:upper>]: ::core::ops::RangeInclusive<u8> = $lo..=$hi; + const [<$field:upper _MASK>]: u32 = ((((1 << $hi) - 1) << 1) + 1) - ((1 << $lo) - 1); + const [<$field:upper _SHIFT>]: u32 = Self::[<$field:upper _MASK>].trailing_zeros(); + ); + + $( + #[doc="Returns the value of this field:"] + #[doc=$comment] + )? + #[inline] + pub(crate) fn $field(self) -> $res_type { + kernel::macros::paste!( + const MASK: u32 = $name::[<$field:upper _MASK>]; + const SHIFT: u32 = $name::[<$field:upper _SHIFT>]; + ); + let field = ((self.0 & MASK) >> SHIFT); + + $process(field) + } + + kernel::macros::paste!( + $( + #[doc="Sets the value of this field:"] + #[doc=$comment] + )? + #[inline] + pub(crate) fn [<set_ $field>](mut self, value: $to_type) -> Self { + const MASK: u32 = $name::[<$field:upper _MASK>]; + const SHIFT: u32 = $name::[<$field:upper _SHIFT>]; + let value = ((value as u32) << SHIFT) & MASK; + self.0 = (self.0 & !MASK) | value; + + self + } + ); + }; + + // Creates the IO accessors for a fixed offset register. + (@io $name:ident @ $offset:literal) => { + #[allow(dead_code)] + impl $name { + #[inline] + pub(crate) fn read<const SIZE: usize, T>(io: &T) -> Self where + T: ::core::ops::Deref<Target = ::kernel::io::Io<SIZE>>, + { + Self(io.read32($offset)) + } + + #[inline] + pub(crate) fn write<const SIZE: usize, T>(self, io: &T) where + T: ::core::ops::Deref<Target = ::kernel::io::Io<SIZE>>, + { + io.write32(self.0, $offset) + } + + #[inline] + pub(crate) fn alter<const SIZE: usize, T, F>( + io: &T, + f: F, + ) where + T: ::core::ops::Deref<Target = ::kernel::io::Io<SIZE>>, + F: ::core::ops::FnOnce(Self) -> Self, + { + let reg = f(Self::read(io)); + reg.write(io); + } + } + }; + + // Create the IO accessors for a relative offset register. + (@io $name:ident @ + $offset:literal) => { + #[allow(dead_code)] + impl $name { + #[inline] + pub(crate) fn read<const SIZE: usize, T>( + io: &T, + base: usize, + ) -> Self where + T: ::core::ops::Deref<Target = ::kernel::io::Io<SIZE>>, + { + Self(io.read32(base + $offset)) + } + + #[inline] + pub(crate) fn write<const SIZE: usize, T>( + self, + io: &T, + base: usize, + ) where + T: ::core::ops::Deref<Target = ::kernel::io::Io<SIZE>>, + { + io.write32(self.0, base + $offset) + } + + #[inline] + pub(crate) fn alter<const SIZE: usize, T, F>( + io: &T, + base: usize, + f: F, + ) where + T: ::core::ops::Deref<Target = ::kernel::io::Io<SIZE>>, + F: ::core::ops::FnOnce(Self) -> Self, + { + let reg = f(Self::read(io, base)); + reg.write(io, base); + } + + #[inline] + pub(crate) fn try_read<const SIZE: usize, T>( + io: &T, + base: usize, + ) -> ::kernel::error::Result<Self> where + T: ::core::ops::Deref<Target = ::kernel::io::Io<SIZE>>, + { + io.try_read32(base + $offset).map(Self) + } + + #[inline] + pub(crate) fn try_write<const SIZE: usize, T>( + self, + io: &T, + base: usize, + ) -> ::kernel::error::Result<()> where + T: ::core::ops::Deref<Target = ::kernel::io::Io<SIZE>>, + { + io.try_write32(self.0, base + $offset) + } + + #[inline] + pub(crate) fn try_alter<const SIZE: usize, T, F>( + io: &T, + base: usize, + f: F, + ) -> ::kernel::error::Result<()> where + T: ::core::ops::Deref<Target = ::kernel::io::Io<SIZE>>, + F: ::core::ops::FnOnce(Self) -> Self, + { + let reg = f(Self::try_read(io, base)?); + reg.try_write(io, base) + } + } + }; +} diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h index a43d707b5f36..63b51942d606 100644 --- a/include/drm/drm_drv.h +++ b/include/drm/drm_drv.h @@ -473,6 +473,11 @@ drmm_cgroup_register_region(struct drm_device *dev, struct drm_device *drm_dev_alloc(const struct drm_driver *driver, struct device *parent); + +void *__drm_dev_alloc(struct device *parent, + const struct drm_driver *driver, + size_t size, size_t offset); + int drm_dev_register(struct drm_device *dev, unsigned long flags); void drm_dev_unregister(struct drm_device *dev); diff --git a/include/uapi/drm/nova_drm.h b/include/uapi/drm/nova_drm.h new file mode 100644 index 000000000000..3ca90ed9d2bb --- /dev/null +++ b/include/uapi/drm/nova_drm.h @@ -0,0 +1,101 @@ +/* SPDX-License-Identifier: MIT */ + +#ifndef __NOVA_DRM_H__ +#define __NOVA_DRM_H__ + +#include "drm.h" + +/* DISCLAIMER: Do not use, this is not a stable uAPI. + * + * This uAPI serves only testing purposes as long as this driver is still in + * development. It is required to implement and test infrastructure which is + * upstreamed in the context of this driver. See also [1]. + * + * [1] https://lore.kernel.org/dri-devel/Zfsj0_tb-0-tNrJy@cassiopeiae/T/#u + */ + +#if defined(__cplusplus) +extern "C" { +#endif + +/* + * NOVA_GETPARAM_VRAM_BAR_SIZE + * + * Query the VRAM BAR size in bytes. + */ +#define NOVA_GETPARAM_VRAM_BAR_SIZE 0x1 + +/** + * struct drm_nova_getparam - query GPU and driver metadata + */ +struct drm_nova_getparam { + /** + * @param: The identifier of the parameter to query. + */ + __u64 param; + + /** + * @value: The value for the specified parameter. + */ + __u64 value; +}; + +/** + * struct drm_nova_gem_create - create a new DRM GEM object + */ +struct drm_nova_gem_create { + /** + * @handle: The handle of the new DRM GEM object. + */ + __u32 handle; + + /** + * @pad: 32 bit padding, should be 0. + */ + __u32 pad; + + /** + * @size: The size of the new DRM GEM object. + */ + __u64 size; +}; + +/** + * struct drm_nova_gem_info - query DRM GEM object metadata + */ +struct drm_nova_gem_info { + /** + * @handle: The handle of the DRM GEM object to query. + */ + __u32 handle; + + /** + * @pad: 32 bit padding, should be 0. + */ + __u32 pad; + + /** + * @size: The size of the DRM GEM obejct. + */ + __u64 size; +}; + +#define DRM_NOVA_GETPARAM 0x00 +#define DRM_NOVA_GEM_CREATE 0x01 +#define DRM_NOVA_GEM_INFO 0x02 + +/* Note: this is an enum so that it can be resolved by Rust bindgen. */ +enum { + DRM_IOCTL_NOVA_GETPARAM = DRM_IOWR(DRM_COMMAND_BASE + DRM_NOVA_GETPARAM, + struct drm_nova_getparam), + DRM_IOCTL_NOVA_GEM_CREATE = DRM_IOWR(DRM_COMMAND_BASE + DRM_NOVA_GEM_CREATE, + struct drm_nova_gem_create), + DRM_IOCTL_NOVA_GEM_INFO = DRM_IOWR(DRM_COMMAND_BASE + DRM_NOVA_GEM_INFO, + struct drm_nova_gem_info), +}; + +#if defined(__cplusplus) +} +#endif + +#endif /* __NOVA_DRM_H__ */ diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h index ab37e1d35c70..e0676ba99d37 100644 --- a/rust/bindings/bindings_helper.h +++ b/rust/bindings/bindings_helper.h @@ -6,7 +6,13 @@ * Sorted alphabetically. */ +#include <drm/drm_device.h> +#include <drm/drm_drv.h> +#include <drm/drm_file.h> +#include <drm/drm_gem.h> +#include <drm/drm_ioctl.h> #include <kunit/test.h> +#include <linux/auxiliary_bus.h> #include <linux/blk-mq.h> #include <linux/blk_types.h> #include <linux/blkdev.h> @@ -55,3 +61,4 @@ const gfp_t RUST_CONST_HELPER___GFP_ZERO = __GFP_ZERO; const gfp_t RUST_CONST_HELPER___GFP_HIGHMEM = ___GFP_HIGHMEM; const gfp_t RUST_CONST_HELPER___GFP_NOWARN = ___GFP_NOWARN; const blk_features_t RUST_CONST_HELPER_BLK_FEAT_ROTATIONAL = BLK_FEAT_ROTATIONAL; +const fop_flags_t RUST_CONST_HELPER_FOP_UNSIGNED_OFFSET = FOP_UNSIGNED_OFFSET; diff --git a/rust/helpers/auxiliary.c b/rust/helpers/auxiliary.c new file mode 100644 index 000000000000..0db3860d774e --- /dev/null +++ b/rust/helpers/auxiliary.c @@ -0,0 +1,23 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/auxiliary_bus.h> + +void rust_helper_auxiliary_set_drvdata(struct auxiliary_device *adev, void *data) +{ + auxiliary_set_drvdata(adev, data); +} + +void *rust_helper_auxiliary_get_drvdata(struct auxiliary_device *adev) +{ + return auxiliary_get_drvdata(adev); +} + +void rust_helper_auxiliary_device_uninit(struct auxiliary_device *adev) +{ + return auxiliary_device_uninit(adev); +} + +void rust_helper_auxiliary_device_delete(struct auxiliary_device *adev) +{ + return auxiliary_device_delete(adev); +} diff --git a/rust/helpers/drm.c b/rust/helpers/drm.c new file mode 100644 index 000000000000..450b406c6f27 --- /dev/null +++ b/rust/helpers/drm.c @@ -0,0 +1,23 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <drm/drm_gem.h> +#include <drm/drm_vma_manager.h> + +#ifdef CONFIG_DRM + +void rust_helper_drm_gem_object_get(struct drm_gem_object *obj) +{ + drm_gem_object_get(obj); +} + +void rust_helper_drm_gem_object_put(struct drm_gem_object *obj) +{ + drm_gem_object_put(obj); +} + +__u64 rust_helper_drm_vma_node_offset_addr(struct drm_vma_offset_node *node) +{ + return drm_vma_node_offset_addr(node); +} + +#endif diff --git a/rust/helpers/helpers.c b/rust/helpers/helpers.c index 1e7c84df7252..c228a5363212 100644 --- a/rust/helpers/helpers.c +++ b/rust/helpers/helpers.c @@ -7,6 +7,7 @@ * Sorted alphabetically. */ +#include "auxiliary.c" #include "blk.c" #include "bug.c" #include "build_assert.c" @@ -15,6 +16,7 @@ #include "cred.c" #include "device.c" #include "dma.c" +#include "drm.c" #include "err.c" #include "fs.c" #include "io.c" diff --git a/rust/helpers/pci.c b/rust/helpers/pci.c index 8ba22f911459..cd0e6bf2cc4d 100644 --- a/rust/helpers/pci.c +++ b/rust/helpers/pci.c @@ -16,3 +16,8 @@ resource_size_t rust_helper_pci_resource_len(struct pci_dev *pdev, int bar) { return pci_resource_len(pdev, bar); } + +bool rust_helper_dev_is_pci(const struct device *dev) +{ + return dev_is_pci(dev); +} diff --git a/rust/helpers/platform.c b/rust/helpers/platform.c index ab9b9f317301..82171233d12f 100644 --- a/rust/helpers/platform.c +++ b/rust/helpers/platform.c @@ -11,3 +11,8 @@ void rust_helper_platform_set_drvdata(struct platform_device *pdev, void *data) { platform_set_drvdata(pdev, data); } + +bool rust_helper_dev_is_platform(const struct device *dev) +{ + return dev_is_platform(dev); +} diff --git a/rust/kernel/auxiliary.rs b/rust/kernel/auxiliary.rs new file mode 100644 index 000000000000..5c072960dee0 --- /dev/null +++ b/rust/kernel/auxiliary.rs @@ -0,0 +1,360 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! Abstractions for the auxiliary bus. +//! +//! C header: [`include/linux/auxiliary_bus.h`](srctree/include/linux/auxiliary_bus.h) + +use crate::{ + bindings, container_of, device, + device_id::RawDeviceId, + driver, + error::{to_result, Result}, + prelude::*, + str::CStr, + types::{ForeignOwnable, Opaque}, + ThisModule, +}; +use core::{ + marker::PhantomData, + ptr::{addr_of_mut, NonNull}, +}; + +/// An adapter for the registration of auxiliary drivers. +pub struct Adapter<T: Driver>(T); + +// SAFETY: A call to `unregister` for a given instance of `RegType` is guaranteed to be valid if +// a preceding call to `register` has been successful. +unsafe impl<T: Driver + 'static> driver::RegistrationOps for Adapter<T> { + type RegType = bindings::auxiliary_driver; + + unsafe fn register( + adrv: &Opaque<Self::RegType>, + name: &'static CStr, + module: &'static ThisModule, + ) -> Result { + // SAFETY: It's safe to set the fields of `struct auxiliary_driver` on initialization. + unsafe { + (*adrv.get()).name = name.as_char_ptr(); + (*adrv.get()).probe = Some(Self::probe_callback); + (*adrv.get()).remove = Some(Self::remove_callback); + (*adrv.get()).id_table = T::ID_TABLE.as_ptr(); + } + + // SAFETY: `adrv` is guaranteed to be a valid `RegType`. + to_result(unsafe { + bindings::__auxiliary_driver_register(adrv.get(), module.0, name.as_char_ptr()) + }) + } + + unsafe fn unregister(adrv: &Opaque<Self::RegType>) { + // SAFETY: `adrv` is guaranteed to be a valid `RegType`. + unsafe { bindings::auxiliary_driver_unregister(adrv.get()) } + } +} + +impl<T: Driver + 'static> Adapter<T> { + extern "C" fn probe_callback( + adev: *mut bindings::auxiliary_device, + id: *const bindings::auxiliary_device_id, + ) -> kernel::ffi::c_int { + // SAFETY: The auxiliary bus only ever calls the probe callback with a valid pointer to a + // `struct auxiliary_device`. + // + // INVARIANT: `adev` is valid for the duration of `probe_callback()`. + let adev = unsafe { &*adev.cast::<Device<device::Core>>() }; + + // SAFETY: `DeviceId` is a `#[repr(transparent)`] wrapper of `struct auxiliary_device_id` + // and does not add additional invariants, so it's safe to transmute. + let id = unsafe { &*id.cast::<DeviceId>() }; + let info = T::ID_TABLE.info(id.index()); + + match T::probe(adev, info) { + Ok(data) => { + // Let the `struct auxiliary_device` own a reference of the driver's private data. + // SAFETY: By the type invariant `adev.as_raw` returns a valid pointer to a + // `struct auxiliary_device`. + unsafe { bindings::auxiliary_set_drvdata(adev.as_raw(), data.into_foreign()) }; + } + Err(err) => return Error::to_errno(err), + } + + 0 + } + + extern "C" fn remove_callback(adev: *mut bindings::auxiliary_device) { + // SAFETY: The auxiliary bus only ever calls the remove callback with a valid pointer to a + // `struct auxiliary_device`. + let ptr = unsafe { bindings::auxiliary_get_drvdata(adev) }; + + // SAFETY: `remove_callback` is only ever called after a successful call to + // `probe_callback`, hence it's guaranteed that `ptr` points to a valid and initialized + // `KBox<T>` pointer created through `KBox::into_foreign`. + drop(unsafe { KBox::<T>::from_foreign(ptr) }); + } +} + +/// Declares a kernel module that exposes a single auxiliary driver. +#[macro_export] +macro_rules! module_auxiliary_driver { + ($($f:tt)*) => { + $crate::module_driver!(<T>, $crate::auxiliary::Adapter<T>, { $($f)* }); + }; +} + +/// Abstraction for `bindings::auxiliary_device_id`. +#[repr(transparent)] +#[derive(Clone, Copy)] +pub struct DeviceId(bindings::auxiliary_device_id); + +impl DeviceId { + /// Create a new [`DeviceId`] from name. + pub const fn new(modname: &'static CStr, name: &'static CStr) -> Self { + let name = name.as_bytes_with_nul(); + let modname = modname.as_bytes_with_nul(); + + // TODO: Replace with `bindings::auxiliary_device_id::default()` once stabilized for + // `const`. + // + // SAFETY: FFI type is valid to be zero-initialized. + let mut id: bindings::auxiliary_device_id = unsafe { core::mem::zeroed() }; + + let mut i = 0; + while i < modname.len() { + id.name[i] = modname[i]; + i += 1; + } + + // Reuse the space of the NULL terminator. + id.name[i - 1] = b'.'; + + let mut j = 0; + while j < name.len() { + id.name[i] = name[j]; + i += 1; + j += 1; + } + + Self(id) + } +} + +// SAFETY: +// * `DeviceId` is a `#[repr(transparent)`] wrapper of `auxiliary_device_id` and does not add +// additional invariants, so it's safe to transmute to `RawType`. +// * `DRIVER_DATA_OFFSET` is the offset to the `driver_data` field. +unsafe impl RawDeviceId for DeviceId { + type RawType = bindings::auxiliary_device_id; + + const DRIVER_DATA_OFFSET: usize = + core::mem::offset_of!(bindings::auxiliary_device_id, driver_data); + + fn index(&self) -> usize { + self.0.driver_data + } +} + +/// IdTable type for auxiliary drivers. +pub type IdTable<T> = &'static dyn kernel::device_id::IdTable<DeviceId, T>; + +/// Create a auxiliary `IdTable` with its alias for modpost. +#[macro_export] +macro_rules! auxiliary_device_table { + ($table_name:ident, $module_table_name:ident, $id_info_type: ty, $table_data: expr) => { + const $table_name: $crate::device_id::IdArray< + $crate::auxiliary::DeviceId, + $id_info_type, + { $table_data.len() }, + > = $crate::device_id::IdArray::new($table_data); + + $crate::module_device_table!("auxiliary", $module_table_name, $table_name); + }; +} + +/// The auxiliary driver trait. +/// +/// Drivers must implement this trait in order to get an auxiliary driver registered. +pub trait Driver { + /// The type holding information about each device id supported by the driver. + /// + /// TODO: Use associated_type_defaults once stabilized: + /// + /// type IdInfo: 'static = (); + type IdInfo: 'static; + + /// The table of device ids supported by the driver. + const ID_TABLE: IdTable<Self::IdInfo>; + + /// Auxiliary driver probe. + /// + /// Called when an auxiliary device is matches a corresponding driver. + fn probe(dev: &Device<device::Core>, id_info: &Self::IdInfo) -> Result<Pin<KBox<Self>>>; +} + +/// The auxiliary device representation. +/// +/// This structure represents the Rust abstraction for a C `struct auxiliary_device`. The +/// implementation abstracts the usage of an already existing C `struct auxiliary_device` within +/// Rust code that we get passed from the C side. +/// +/// # Invariants +/// +/// A [`Device`] instance represents a valid `struct auxiliary_device` created by the C portion of +/// the kernel. +#[repr(transparent)] +pub struct Device<Ctx: device::DeviceContext = device::Normal>( + Opaque<bindings::auxiliary_device>, + PhantomData<Ctx>, +); + +impl<Ctx: device::DeviceContext> Device<Ctx> { + fn as_raw(&self) -> *mut bindings::auxiliary_device { + self.0.get() + } + + /// Returns the auxiliary device' id. + pub fn id(&self) -> u32 { + // SAFETY: By the type invariant `self.as_raw()` is a valid pointer to a + // `struct auxiliary_device`. + unsafe { (*self.as_raw()).id } + } + + /// Returns a reference to the parent [`device::Device`], if any. + pub fn parent(&self) -> Option<&device::Device> { + let ptr: *const Self = self; + // CAST: `Device<Ctx: DeviceContext>` types are transparent to each other. + let ptr: *const Device = ptr.cast(); + // SAFETY: `ptr` was derived from `&self`. + let this = unsafe { &*ptr }; + + this.as_ref().parent() + } +} + +impl Device { + extern "C" fn release(dev: *mut bindings::device) { + // SAFETY: By the type invariant `self.0.as_raw` is a pointer to the `struct device` + // embedded in `struct auxiliary_device`. + let adev = unsafe { container_of!(dev, bindings::auxiliary_device, dev) }.cast_mut(); + + // SAFETY: `adev` points to the memory that has been allocated in `Registration::new`, via + // `KBox::new(Opaque::<bindings::auxiliary_device>::zeroed(), GFP_KERNEL)`. + let _ = unsafe { KBox::<Opaque<bindings::auxiliary_device>>::from_raw(adev.cast()) }; + } +} + +// SAFETY: `Device` is a transparent wrapper of a type that doesn't depend on `Device`'s generic +// argument. +kernel::impl_device_context_deref!(unsafe { Device }); +kernel::impl_device_context_into_aref!(Device); + +// SAFETY: Instances of `Device` are always reference-counted. +unsafe impl crate::types::AlwaysRefCounted for Device { + fn inc_ref(&self) { + // SAFETY: The existence of a shared reference guarantees that the refcount is non-zero. + unsafe { bindings::get_device(self.as_ref().as_raw()) }; + } + + unsafe fn dec_ref(obj: NonNull<Self>) { + // CAST: `Self` a transparent wrapper of `bindings::auxiliary_device`. + let adev: *mut bindings::auxiliary_device = obj.cast().as_ptr(); + + // SAFETY: By the type invariant of `Self`, `adev` is a pointer to a valid + // `struct auxiliary_device`. + let dev = unsafe { addr_of_mut!((*adev).dev) }; + + // SAFETY: The safety requirements guarantee that the refcount is non-zero. + unsafe { bindings::put_device(dev) } + } +} + +impl<Ctx: device::DeviceContext> AsRef<device::Device<Ctx>> for Device<Ctx> { + fn as_ref(&self) -> &device::Device<Ctx> { + // SAFETY: By the type invariant of `Self`, `self.as_raw()` is a pointer to a valid + // `struct auxiliary_device`. + let dev = unsafe { addr_of_mut!((*self.as_raw()).dev) }; + + // SAFETY: `dev` points to a valid `struct device`. + unsafe { device::Device::as_ref(dev) } + } +} + +// SAFETY: A `Device` is always reference-counted and can be released from any thread. +unsafe impl Send for Device {} + +// SAFETY: `Device` can be shared among threads because all methods of `Device` +// (i.e. `Device<Normal>) are thread safe. +unsafe impl Sync for Device {} + +/// The registration of an auxiliary device. +/// +/// This type represents the registration of a [`struct auxiliary_device`]. When an instance of this +/// type is dropped, its respective auxiliary device will be unregistered from the system. +/// +/// # Invariants +/// +/// `self.0` always holds a valid pointer to an initialized and registered +/// [`struct auxiliary_device`]. +pub struct Registration(NonNull<bindings::auxiliary_device>); + +impl Registration { + /// Create and register a new auxiliary device. + pub fn new(parent: &device::Device, name: &CStr, id: u32, modname: &CStr) -> Result<Self> { + let boxed = KBox::new(Opaque::<bindings::auxiliary_device>::zeroed(), GFP_KERNEL)?; + let adev = boxed.get(); + + // SAFETY: It's safe to set the fields of `struct auxiliary_device` on initialization. + unsafe { + (*adev).dev.parent = parent.as_raw(); + (*adev).dev.release = Some(Device::release); + (*adev).name = name.as_char_ptr(); + (*adev).id = id; + } + + // SAFETY: `adev` is guaranteed to be a valid pointer to a `struct auxiliary_device`, + // which has not been initialized yet. + unsafe { bindings::auxiliary_device_init(adev) }; + + // Now that `adev` is initialized, leak the `Box`; the corresponding memory will be freed + // by `Device::release` when the last reference to the `struct auxiliary_device` is dropped. + let _ = KBox::into_raw(boxed); + + // SAFETY: + // - `adev` is guaranteed to be a valid pointer to a `struct auxiliary_device`, which has + // been initialialized, + // - `modname.as_char_ptr()` is a NULL terminated string. + let ret = unsafe { bindings::__auxiliary_device_add(adev, modname.as_char_ptr()) }; + if ret != 0 { + // SAFETY: `adev` is guaranteed to be a valid pointer to a `struct auxiliary_device`, + // which has been initialialized. + unsafe { bindings::auxiliary_device_uninit(adev) }; + + return Err(Error::from_errno(ret)); + } + + // SAFETY: `adev` is guaranteed to be non-null, since the `KBox` was allocated successfully. + // + // INVARIANT: The device will remain registered until `auxiliary_device_delete()` is called, + // which happens in `Self::drop()`. + Ok(Self(unsafe { NonNull::new_unchecked(adev) })) + } +} + +impl Drop for Registration { + fn drop(&mut self) { + // SAFETY: By the type invariant of `Self`, `self.0.as_ptr()` is a valid registered + // `struct auxiliary_device`. + unsafe { bindings::auxiliary_device_delete(self.0.as_ptr()) }; + + // This drops the reference we acquired through `auxiliary_device_init()`. + // + // SAFETY: By the type invariant of `Self`, `self.0.as_ptr()` is a valid registered + // `struct auxiliary_device`. + unsafe { bindings::auxiliary_device_uninit(self.0.as_ptr()) }; + } +} + +// SAFETY: A `Registration` of a `struct auxiliary_device` can be released from any thread. +unsafe impl Send for Registration {} + +// SAFETY: `Registration` does not expose any methods or fields that need synchronization. +unsafe impl Sync for Registration {} diff --git a/rust/kernel/device.rs b/rust/kernel/device.rs index 21b343a1dc4d..f08583fa39c9 100644 --- a/rust/kernel/device.rs +++ b/rust/kernel/device.rs @@ -9,7 +9,7 @@ use crate::{ str::CStr, types::{ARef, Opaque}, }; -use core::{fmt, ptr}; +use core::{fmt, marker::PhantomData, ptr}; #[cfg(CONFIG_PRINTK)] use crate::c_str; @@ -42,7 +42,7 @@ use crate::c_str; /// `bindings::device::release` is valid to be called from any thread, hence `ARef<Device>` can be /// dropped from any thread. #[repr(transparent)] -pub struct Device(Opaque<bindings::device>); +pub struct Device<Ctx: DeviceContext = Normal>(Opaque<bindings::device>, PhantomData<Ctx>); impl Device { /// Creates a new reference-counted abstraction instance of an existing `struct device` pointer. @@ -59,12 +59,33 @@ impl Device { // SAFETY: By the safety requirements ptr is valid unsafe { Self::as_ref(ptr) }.into() } +} +impl<Ctx: DeviceContext> Device<Ctx> { /// Obtain the raw `struct device *`. pub(crate) fn as_raw(&self) -> *mut bindings::device { self.0.get() } + /// Returns a reference to the parent device, if any. + #[cfg_attr(not(CONFIG_AUXILIARY_BUS), expect(dead_code))] + pub(crate) fn parent(&self) -> Option<&Self> { + // SAFETY: + // - By the type invariant `self.as_raw()` is always valid. + // - The parent device is only ever set at device creation. + let parent = unsafe { (*self.as_raw()).parent }; + + if parent.is_null() { + None + } else { + // SAFETY: + // - Since `parent` is not NULL, it must be a valid pointer to a `struct device`. + // - `parent` is valid for the lifetime of `self`, since a `struct device` holds a + // reference count of its parent. + Some(unsafe { Self::as_ref(parent) }) + } + } + /// Convert a raw C `struct device` pointer to a `&'a Device`. /// /// # Safety @@ -189,6 +210,11 @@ impl Device { } } +// SAFETY: `Device` is a transparent wrapper of a type that doesn't depend on `Device`'s generic +// argument. +kernel::impl_device_context_deref!(unsafe { Device }); +kernel::impl_device_context_into_aref!(Device); + // SAFETY: Instances of `Device` are always reference-counted. unsafe impl crate::types::AlwaysRefCounted for Device { fn inc_ref(&self) { @@ -225,16 +251,95 @@ pub struct Normal; /// any of the bus callbacks, such as `probe()`. pub struct Core; +/// The [`Bound`] context is the context of a bus specific device reference when it is guaranteed to +/// be bound for the duration of its lifetime. +pub struct Bound; + mod private { pub trait Sealed {} + impl Sealed for super::Bound {} impl Sealed for super::Core {} impl Sealed for super::Normal {} } +impl DeviceContext for Bound {} impl DeviceContext for Core {} impl DeviceContext for Normal {} +/// # Safety +/// +/// The type given as `$device` must be a transparent wrapper of a type that doesn't depend on the +/// generic argument of `$device`. +#[doc(hidden)] +#[macro_export] +macro_rules! __impl_device_context_deref { + (unsafe { $device:ident, $src:ty => $dst:ty }) => { + impl ::core::ops::Deref for $device<$src> { + type Target = $device<$dst>; + + fn deref(&self) -> &Self::Target { + let ptr: *const Self = self; + + // CAST: `$device<$src>` and `$device<$dst>` transparently wrap the same type by the + // safety requirement of the macro. + let ptr = ptr.cast::<Self::Target>(); + + // SAFETY: `ptr` was derived from `&self`. + unsafe { &*ptr } + } + } + }; +} + +/// Implement [`core::ops::Deref`] traits for allowed [`DeviceContext`] conversions of a (bus +/// specific) device. +/// +/// # Safety +/// +/// The type given as `$device` must be a transparent wrapper of a type that doesn't depend on the +/// generic argument of `$device`. +#[macro_export] +macro_rules! impl_device_context_deref { + (unsafe { $device:ident }) => { + // SAFETY: This macro has the exact same safety requirement as + // `__impl_device_context_deref!`. + ::kernel::__impl_device_context_deref!(unsafe { + $device, + $crate::device::Core => $crate::device::Bound + }); + + // SAFETY: This macro has the exact same safety requirement as + // `__impl_device_context_deref!`. + ::kernel::__impl_device_context_deref!(unsafe { + $device, + $crate::device::Bound => $crate::device::Normal + }); + }; +} + +#[doc(hidden)] +#[macro_export] +macro_rules! __impl_device_context_into_aref { + ($src:ty, $device:tt) => { + impl ::core::convert::From<&$device<$src>> for $crate::types::ARef<$device> { + fn from(dev: &$device<$src>) -> Self { + (&**dev).into() + } + } + }; +} + +/// Implement [`core::convert::From`], such that all `&Device<Ctx>` can be converted to an +/// `ARef<Device>`. +#[macro_export] +macro_rules! impl_device_context_into_aref { + ($device:tt) => { + ::kernel::__impl_device_context_into_aref!($crate::device::Core, $device); + ::kernel::__impl_device_context_into_aref!($crate::device::Bound, $device); + }; +} + #[doc(hidden)] #[macro_export] macro_rules! dev_printk { diff --git a/rust/kernel/devres.rs b/rust/kernel/devres.rs index ddb1ce4a78d9..0f79a2ec9474 100644 --- a/rust/kernel/devres.rs +++ b/rust/kernel/devres.rs @@ -8,7 +8,7 @@ use crate::{ alloc::Flags, bindings, - device::Device, + device::{Bound, Device}, error::{Error, Result}, ffi::c_void, prelude::*, @@ -45,7 +45,7 @@ struct DevresInner<T> { /// # Example /// /// ```no_run -/// # use kernel::{bindings, c_str, device::Device, devres::Devres, io::{Io, IoRaw}}; +/// # use kernel::{bindings, c_str, device::{Bound, Device}, devres::Devres, io::{Io, IoRaw}}; /// # use core::ops::Deref; /// /// // See also [`pci::Bar`] for a real example. @@ -83,13 +83,10 @@ struct DevresInner<T> { /// unsafe { Io::from_raw(&self.0) } /// } /// } -/// # fn no_run() -> Result<(), Error> { -/// # // SAFETY: Invalid usage; just for the example to get an `ARef<Device>` instance. -/// # let dev = unsafe { Device::get_device(core::ptr::null_mut()) }; -/// +/// # fn no_run(dev: &Device<Bound>) -> Result<(), Error> { /// // SAFETY: Invalid usage for example purposes. /// let iomem = unsafe { IoMem::<{ core::mem::size_of::<u32>() }>::new(0xBAAAAAAD)? }; -/// let devres = Devres::new(&dev, iomem, GFP_KERNEL)?; +/// let devres = Devres::new(dev, iomem, GFP_KERNEL)?; /// /// let res = devres.try_access().ok_or(ENXIO)?; /// res.write8(0x42, 0x0); @@ -99,7 +96,7 @@ struct DevresInner<T> { pub struct Devres<T>(Arc<DevresInner<T>>); impl<T> DevresInner<T> { - fn new(dev: &Device, data: T, flags: Flags) -> Result<Arc<DevresInner<T>>> { + fn new(dev: &Device<Bound>, data: T, flags: Flags) -> Result<Arc<DevresInner<T>>> { let inner = Arc::pin_init( pin_init!( DevresInner { dev: dev.into(), @@ -171,7 +168,7 @@ impl<T> DevresInner<T> { impl<T> Devres<T> { /// Creates a new [`Devres`] instance of the given `data`. The `data` encapsulated within the /// returned `Devres` instance' `data` will be revoked once the device is detached. - pub fn new(dev: &Device, data: T, flags: Flags) -> Result<Self> { + pub fn new(dev: &Device<Bound>, data: T, flags: Flags) -> Result<Self> { let inner = DevresInner::new(dev, data, flags)?; Ok(Devres(inner)) @@ -179,11 +176,50 @@ impl<T> Devres<T> { /// Same as [`Devres::new`], but does not return a `Devres` instance. Instead the given `data` /// is owned by devres and will be revoked / dropped, once the device is detached. - pub fn new_foreign_owned(dev: &Device, data: T, flags: Flags) -> Result { + pub fn new_foreign_owned(dev: &Device<Bound>, data: T, flags: Flags) -> Result { let _ = DevresInner::new(dev, data, flags)?; Ok(()) } + + /// Obtain `&'a T`, bypassing the [`Revocable`]. + /// + /// This method allows to directly obtain a `&'a T`, bypassing the [`Revocable`], by presenting + /// a `&'a Device<Bound>` of the same [`Device`] this [`Devres`] instance has been created with. + /// + /// # Errors + /// + /// An error is returned if `dev` does not match the same [`Device`] this [`Devres`] instance + /// has been created with. + /// + /// # Example + /// + /// ```no_run + /// # #![cfg(CONFIG_PCI)] + /// # use kernel::{device::Core, devres::Devres, pci}; + /// + /// fn from_core(dev: &pci::Device<Core>, devres: Devres<pci::Bar<0x4>>) -> Result { + /// let bar = devres.access(dev.as_ref())?; + /// + /// let _ = bar.read32(0x0); + /// + /// // might_sleep() + /// + /// bar.write32(0x42, 0x0); + /// + /// Ok(()) + /// } + /// ``` + pub fn access<'a>(&'a self, dev: &'a Device<Bound>) -> Result<&'a T> { + if self.0.dev.as_raw() != dev.as_raw() { + return Err(EINVAL); + } + + // SAFETY: `dev` being the same device as the device this `Devres` has been created for + // proves that `self.0.data` hasn't been revoked and is guaranteed to not be revoked as + // long as `dev` lives; `dev` lives at least as long as `self`. + Ok(unsafe { self.deref().access() }) + } } impl<T> Deref for Devres<T> { diff --git a/rust/kernel/dma.rs b/rust/kernel/dma.rs index 8cdc76043ee7..605e01e35715 100644 --- a/rust/kernel/dma.rs +++ b/rust/kernel/dma.rs @@ -6,7 +6,7 @@ use crate::{ bindings, build_assert, - device::Device, + device::{Bound, Device}, error::code::*, error::Result, transmute::{AsBytes, FromBytes}, @@ -22,10 +22,10 @@ use crate::{ /// # Examples /// /// ``` -/// use kernel::device::Device; +/// # use kernel::device::{Bound, Device}; /// use kernel::dma::{attrs::*, CoherentAllocation}; /// -/// # fn test(dev: &Device) -> Result { +/// # fn test(dev: &Device<Bound>) -> Result { /// let attribs = DMA_ATTR_FORCE_CONTIGUOUS | DMA_ATTR_NO_WARN; /// let c: CoherentAllocation<u64> = /// CoherentAllocation::alloc_attrs(dev, 4, GFP_KERNEL, attribs)?; @@ -143,16 +143,16 @@ impl<T: AsBytes + FromBytes> CoherentAllocation<T> { /// # Examples /// /// ``` - /// use kernel::device::Device; + /// # use kernel::device::{Bound, Device}; /// use kernel::dma::{attrs::*, CoherentAllocation}; /// - /// # fn test(dev: &Device) -> Result { + /// # fn test(dev: &Device<Bound>) -> Result { /// let c: CoherentAllocation<u64> = /// CoherentAllocation::alloc_attrs(dev, 4, GFP_KERNEL, DMA_ATTR_NO_WARN)?; /// # Ok::<(), Error>(()) } /// ``` pub fn alloc_attrs( - dev: &Device, + dev: &Device<Bound>, count: usize, gfp_flags: kernel::alloc::Flags, dma_attrs: Attrs, @@ -194,7 +194,7 @@ impl<T: AsBytes + FromBytes> CoherentAllocation<T> { /// Performs the same functionality as [`CoherentAllocation::alloc_attrs`], except the /// `dma_attrs` is 0 by default. pub fn alloc_coherent( - dev: &Device, + dev: &Device<Bound>, count: usize, gfp_flags: kernel::alloc::Flags, ) -> Result<CoherentAllocation<T>> { diff --git a/rust/kernel/drm/device.rs b/rust/kernel/drm/device.rs new file mode 100644 index 000000000000..74c9a3dd719e --- /dev/null +++ b/rust/kernel/drm/device.rs @@ -0,0 +1,200 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +//! DRM device. +//! +//! C header: [`include/linux/drm/drm_device.h`](srctree/include/linux/drm/drm_device.h) + +use crate::{ + bindings, device, drm, + drm::driver::AllocImpl, + error::from_err_ptr, + error::Result, + prelude::*, + types::{ARef, AlwaysRefCounted, Opaque}, +}; +use core::{mem, ops::Deref, ptr, ptr::NonNull}; + +#[cfg(CONFIG_DRM_LEGACY)] +macro_rules! drm_legacy_fields { + ( $($field:ident: $val:expr),* $(,)? ) => { + bindings::drm_driver { + $( $field: $val ),*, + firstopen: None, + preclose: None, + dma_ioctl: None, + dma_quiescent: None, + context_dtor: None, + irq_handler: None, + irq_preinstall: None, + irq_postinstall: None, + irq_uninstall: None, + get_vblank_counter: None, + enable_vblank: None, + disable_vblank: None, + dev_priv_size: 0, + } + } +} + +#[cfg(not(CONFIG_DRM_LEGACY))] +macro_rules! drm_legacy_fields { + ( $($field:ident: $val:expr),* $(,)? ) => { + bindings::drm_driver { + $( $field: $val ),* + } + } +} + +/// A typed DRM device with a specific `drm::Driver` implementation. +/// +/// The device is always reference-counted. +/// +/// # Invariants +/// +/// `self.dev` is a valid instance of a `struct device`. +#[repr(C)] +#[pin_data] +pub struct Device<T: drm::Driver> { + dev: Opaque<bindings::drm_device>, + #[pin] + data: T::Data, +} + +impl<T: drm::Driver> Device<T> { + const VTABLE: bindings::drm_driver = drm_legacy_fields! { + load: None, + open: Some(drm::File::<T::File>::open_callback), + postclose: Some(drm::File::<T::File>::postclose_callback), + unload: None, + release: None, + master_set: None, + master_drop: None, + debugfs_init: None, + gem_create_object: T::Object::ALLOC_OPS.gem_create_object, + prime_handle_to_fd: T::Object::ALLOC_OPS.prime_handle_to_fd, + prime_fd_to_handle: T::Object::ALLOC_OPS.prime_fd_to_handle, + gem_prime_import: T::Object::ALLOC_OPS.gem_prime_import, + gem_prime_import_sg_table: T::Object::ALLOC_OPS.gem_prime_import_sg_table, + dumb_create: T::Object::ALLOC_OPS.dumb_create, + dumb_map_offset: T::Object::ALLOC_OPS.dumb_map_offset, + show_fdinfo: None, + fbdev_probe: None, + + major: T::INFO.major, + minor: T::INFO.minor, + patchlevel: T::INFO.patchlevel, + name: T::INFO.name.as_char_ptr() as *mut _, + desc: T::INFO.desc.as_char_ptr() as *mut _, + + driver_features: drm::driver::FEAT_GEM, + ioctls: T::IOCTLS.as_ptr(), + num_ioctls: T::IOCTLS.len() as i32, + fops: &Self::GEM_FOPS as _, + }; + + const GEM_FOPS: bindings::file_operations = drm::gem::create_fops(); + + /// Create a new `drm::Device` for a `drm::Driver`. + pub fn new(dev: &device::Device, data: impl PinInit<T::Data, Error>) -> Result<ARef<Self>> { + // SAFETY: + // - `VTABLE`, as a `const` is pinned to the read-only section of the compilation, + // - `dev` is valid by its type invarants, + let raw_drm: *mut Self = unsafe { + bindings::__drm_dev_alloc( + dev.as_raw(), + &Self::VTABLE, + mem::size_of::<Self>(), + mem::offset_of!(Self, dev), + ) + } + .cast(); + let raw_drm = NonNull::new(from_err_ptr(raw_drm)?).ok_or(ENOMEM)?; + + // SAFETY: `raw_drm` is a valid pointer to `Self`. + let raw_data = unsafe { ptr::addr_of_mut!((*raw_drm.as_ptr()).data) }; + + // SAFETY: + // - `raw_data` is a valid pointer to uninitialized memory. + // - `raw_data` will not move until it is dropped. + unsafe { data.__pinned_init(raw_data) }.inspect_err(|_| { + // SAFETY: `__drm_dev_alloc()` was successful, hence `raw_drm` must be valid and the + // refcount must be non-zero. + unsafe { bindings::drm_dev_put(ptr::addr_of_mut!((*raw_drm.as_ptr()).dev).cast()) }; + })?; + + // SAFETY: The reference count is one, and now we take ownership of that reference as a + // `drm::Device`. + Ok(unsafe { ARef::from_raw(raw_drm) }) + } + + pub(crate) fn as_raw(&self) -> *mut bindings::drm_device { + self.dev.get() + } + + /// # Safety + /// + /// `ptr` must be a valid pointer to a `struct device` embedded in `Self`. + unsafe fn from_drm_device(ptr: *const bindings::drm_device) -> *mut Self { + // SAFETY: By the safety requirements of this function `ptr` is a valid pointer to a + // `struct drm_device` embedded in `Self`. + unsafe { crate::container_of!(ptr, Self, dev) }.cast_mut() + } + + /// Not intended to be called externally, except via declare_drm_ioctls!() + /// + /// # Safety + /// + /// Callers must ensure that `ptr` is valid, non-null, and has a non-zero reference count, + /// i.e. it must be ensured that the reference count of the C `struct drm_device` `ptr` points + /// to can't drop to zero, for the duration of this function call and the entire duration when + /// the returned reference exists. + /// + /// Additionally, callers must ensure that the `struct device`, `ptr` is pointing to, is + /// embedded in `Self`. + #[doc(hidden)] + pub unsafe fn as_ref<'a>(ptr: *const bindings::drm_device) -> &'a Self { + // SAFETY: By the safety requirements of this function `ptr` is a valid pointer to a + // `struct drm_device` embedded in `Self`. + let ptr = unsafe { Self::from_drm_device(ptr) }; + + // SAFETY: `ptr` is valid by the safety requirements of this function. + unsafe { &*ptr.cast() } + } +} + +impl<T: drm::Driver> Deref for Device<T> { + type Target = T::Data; + + fn deref(&self) -> &Self::Target { + &self.data + } +} + +// SAFETY: DRM device objects are always reference counted and the get/put functions +// satisfy the requirements. +unsafe impl<T: drm::Driver> AlwaysRefCounted for Device<T> { + fn inc_ref(&self) { + // SAFETY: The existence of a shared reference guarantees that the refcount is non-zero. + unsafe { bindings::drm_dev_get(self.as_raw()) }; + } + + unsafe fn dec_ref(obj: NonNull<Self>) { + // SAFETY: The safety requirements guarantee that the refcount is non-zero. + unsafe { bindings::drm_dev_put(obj.cast().as_ptr()) }; + } +} + +impl<T: drm::Driver> AsRef<device::Device> for Device<T> { + fn as_ref(&self) -> &device::Device { + // SAFETY: `bindings::drm_device::dev` is valid as long as the DRM device itself is valid, + // which is guaranteed by the type invariant. + unsafe { device::Device::as_ref((*self.as_raw()).dev) } + } +} + +// SAFETY: A `drm::Device` can be released from any thread. +unsafe impl<T: drm::Driver> Send for Device<T> {} + +// SAFETY: A `drm::Device` can be shared among threads because all immutable methods are protected +// by the synchronization in `struct drm_device`. +unsafe impl<T: drm::Driver> Sync for Device<T> {} diff --git a/rust/kernel/drm/driver.rs b/rust/kernel/drm/driver.rs new file mode 100644 index 000000000000..acb638086131 --- /dev/null +++ b/rust/kernel/drm/driver.rs @@ -0,0 +1,166 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +//! DRM driver core. +//! +//! C header: [`include/linux/drm/drm_drv.h`](srctree/include/linux/drm/drm_drv.h) + +use crate::{ + bindings, device, + devres::Devres, + drm, + error::{to_result, Result}, + prelude::*, + str::CStr, + types::ARef, +}; +use macros::vtable; + +/// Driver use the GEM memory manager. This should be set for all modern drivers. +pub(crate) const FEAT_GEM: u32 = bindings::drm_driver_feature_DRIVER_GEM; + +/// Information data for a DRM Driver. +pub struct DriverInfo { + /// Driver major version. + pub major: i32, + /// Driver minor version. + pub minor: i32, + /// Driver patchlevel version. + pub patchlevel: i32, + /// Driver name. + pub name: &'static CStr, + /// Driver description. + pub desc: &'static CStr, +} + +/// Internal memory management operation set, normally created by memory managers (e.g. GEM). +pub struct AllocOps { + pub(crate) gem_create_object: Option< + unsafe extern "C" fn( + dev: *mut bindings::drm_device, + size: usize, + ) -> *mut bindings::drm_gem_object, + >, + pub(crate) prime_handle_to_fd: Option< + unsafe extern "C" fn( + dev: *mut bindings::drm_device, + file_priv: *mut bindings::drm_file, + handle: u32, + flags: u32, + prime_fd: *mut core::ffi::c_int, + ) -> core::ffi::c_int, + >, + pub(crate) prime_fd_to_handle: Option< + unsafe extern "C" fn( + dev: *mut bindings::drm_device, + file_priv: *mut bindings::drm_file, + prime_fd: core::ffi::c_int, + handle: *mut u32, + ) -> core::ffi::c_int, + >, + pub(crate) gem_prime_import: Option< + unsafe extern "C" fn( + dev: *mut bindings::drm_device, + dma_buf: *mut bindings::dma_buf, + ) -> *mut bindings::drm_gem_object, + >, + pub(crate) gem_prime_import_sg_table: Option< + unsafe extern "C" fn( + dev: *mut bindings::drm_device, + attach: *mut bindings::dma_buf_attachment, + sgt: *mut bindings::sg_table, + ) -> *mut bindings::drm_gem_object, + >, + pub(crate) dumb_create: Option< + unsafe extern "C" fn( + file_priv: *mut bindings::drm_file, + dev: *mut bindings::drm_device, + args: *mut bindings::drm_mode_create_dumb, + ) -> core::ffi::c_int, + >, + pub(crate) dumb_map_offset: Option< + unsafe extern "C" fn( + file_priv: *mut bindings::drm_file, + dev: *mut bindings::drm_device, + handle: u32, + offset: *mut u64, + ) -> core::ffi::c_int, + >, +} + +/// Trait for memory manager implementations. Implemented internally. +pub trait AllocImpl: super::private::Sealed + drm::gem::IntoGEMObject { + /// The C callback operations for this memory manager. + const ALLOC_OPS: AllocOps; +} + +/// The DRM `Driver` trait. +/// +/// This trait must be implemented by drivers in order to create a `struct drm_device` and `struct +/// drm_driver` to be registered in the DRM subsystem. +#[vtable] +pub trait Driver { + /// Context data associated with the DRM driver + type Data: Sync + Send; + + /// The type used to manage memory for this driver. + type Object: AllocImpl; + + /// The type used to represent a DRM File (client) + type File: drm::file::DriverFile; + + /// Driver metadata + const INFO: DriverInfo; + + /// IOCTL list. See `kernel::drm::ioctl::declare_drm_ioctls!{}`. + const IOCTLS: &'static [drm::ioctl::DrmIoctlDescriptor]; +} + +/// The registration type of a `drm::Device`. +/// +/// Once the `Registration` structure is dropped, the device is unregistered. +pub struct Registration<T: Driver>(ARef<drm::Device<T>>); + +impl<T: Driver> Registration<T> { + /// Creates a new [`Registration`] and registers it. + fn new(drm: &drm::Device<T>, flags: usize) -> Result<Self> { + // SAFETY: `drm.as_raw()` is valid by the invariants of `drm::Device`. + to_result(unsafe { bindings::drm_dev_register(drm.as_raw(), flags) })?; + + Ok(Self(drm.into())) + } + + /// Same as [`Registration::new`}, but transfers ownership of the [`Registration`] to + /// [`Devres`]. + pub fn new_foreign_owned( + drm: &drm::Device<T>, + dev: &device::Device<device::Bound>, + flags: usize, + ) -> Result { + if drm.as_ref().as_raw() != dev.as_raw() { + return Err(EINVAL); + } + + let reg = Registration::<T>::new(drm, flags)?; + Devres::new_foreign_owned(dev, reg, GFP_KERNEL) + } + + /// Returns a reference to the `Device` instance for this registration. + pub fn device(&self) -> &drm::Device<T> { + &self.0 + } +} + +// SAFETY: `Registration` doesn't offer any methods or access to fields when shared between +// threads, hence it's safe to share it. +unsafe impl<T: Driver> Sync for Registration<T> {} + +// SAFETY: Registration with and unregistration from the DRM subsystem can happen from any thread. +unsafe impl<T: Driver> Send for Registration<T> {} + +impl<T: Driver> Drop for Registration<T> { + fn drop(&mut self) { + // SAFETY: Safe by the invariant of `ARef<drm::Device<T>>`. The existence of this + // `Registration` also guarantees the this `drm::Device` is actually registered. + unsafe { bindings::drm_dev_unregister(self.0.as_raw()) }; + } +} diff --git a/rust/kernel/drm/file.rs b/rust/kernel/drm/file.rs new file mode 100644 index 000000000000..b9527705e551 --- /dev/null +++ b/rust/kernel/drm/file.rs @@ -0,0 +1,99 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +//! DRM File objects. +//! +//! C header: [`include/linux/drm/drm_file.h`](srctree/include/linux/drm/drm_file.h) + +use crate::{bindings, drm, error::Result, prelude::*, types::Opaque}; +use core::marker::PhantomData; +use core::pin::Pin; + +/// Trait that must be implemented by DRM drivers to represent a DRM File (a client instance). +pub trait DriverFile { + /// The parent `Driver` implementation for this `DriverFile`. + type Driver: drm::Driver; + + /// Open a new file (called when a client opens the DRM device). + fn open(device: &drm::Device<Self::Driver>) -> Result<Pin<KBox<Self>>>; +} + +/// An open DRM File. +/// +/// # Invariants +/// +/// `self.0` is a valid instance of a `struct drm_file`. +#[repr(transparent)] +pub struct File<T: DriverFile>(Opaque<bindings::drm_file>, PhantomData<T>); + +impl<T: DriverFile> File<T> { + #[doc(hidden)] + /// Not intended to be called externally, except via declare_drm_ioctls!() + /// + /// # Safety + /// + /// `raw_file` must be a valid pointer to an open `struct drm_file`, opened through `T::open`. + pub unsafe fn as_ref<'a>(ptr: *mut bindings::drm_file) -> &'a File<T> { + // SAFETY: `raw_file` is valid by the safety requirements of this function. + unsafe { &*ptr.cast() } + } + + pub(super) fn as_raw(&self) -> *mut bindings::drm_file { + self.0.get() + } + + fn driver_priv(&self) -> *mut T { + // SAFETY: By the type invariants of `Self`, `self.as_raw()` is always valid. + unsafe { (*self.as_raw()).driver_priv }.cast() + } + + /// Return a pinned reference to the driver file structure. + pub fn inner(&self) -> Pin<&T> { + // SAFETY: By the type invariant the pointer `self.as_raw()` points to a valid and opened + // `struct drm_file`, hence `driver_priv` has been properly initialized by `open_callback`. + unsafe { Pin::new_unchecked(&*(self.driver_priv())) } + } + + /// The open callback of a `struct drm_file`. + pub(crate) extern "C" fn open_callback( + raw_dev: *mut bindings::drm_device, + raw_file: *mut bindings::drm_file, + ) -> core::ffi::c_int { + // SAFETY: A callback from `struct drm_driver::open` guarantees that + // - `raw_dev` is valid pointer to a `struct drm_device`, + // - the corresponding `struct drm_device` has been registered. + let drm = unsafe { drm::Device::as_ref(raw_dev) }; + + // SAFETY: `raw_file` is a valid pointer to a `struct drm_file`. + let file = unsafe { File::<T>::as_ref(raw_file) }; + + let inner = match T::open(drm) { + Err(e) => { + return e.to_errno(); + } + Ok(i) => i, + }; + + // SAFETY: This pointer is treated as pinned, and the Drop guarantee is upheld in + // `postclose_callback()`. + let driver_priv = KBox::into_raw(unsafe { Pin::into_inner_unchecked(inner) }); + + // SAFETY: By the type invariants of `Self`, `self.as_raw()` is always valid. + unsafe { (*file.as_raw()).driver_priv = driver_priv.cast() }; + + 0 + } + + /// The postclose callback of a `struct drm_file`. + pub(crate) extern "C" fn postclose_callback( + _raw_dev: *mut bindings::drm_device, + raw_file: *mut bindings::drm_file, + ) { + // SAFETY: This reference won't escape this function + let file = unsafe { File::<T>::as_ref(raw_file) }; + + // SAFETY: `file.driver_priv` has been created in `open_callback` through `KBox::into_raw`. + let _ = unsafe { KBox::from_raw(file.driver_priv()) }; + } +} + +impl<T: DriverFile> super::private::Sealed for File<T> {} diff --git a/rust/kernel/drm/gem/mod.rs b/rust/kernel/drm/gem/mod.rs new file mode 100644 index 000000000000..d8765e61c6c2 --- /dev/null +++ b/rust/kernel/drm/gem/mod.rs @@ -0,0 +1,328 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +//! DRM GEM API +//! +//! C header: [`include/linux/drm/drm_gem.h`](srctree/include/linux/drm/drm_gem.h) + +use crate::{ + alloc::flags::*, + bindings, drm, + drm::driver::{AllocImpl, AllocOps}, + error::{to_result, Result}, + prelude::*, + types::{ARef, AlwaysRefCounted, Opaque}, +}; +use core::{mem, ops::Deref, ptr::NonNull}; + +/// GEM object functions, which must be implemented by drivers. +pub trait BaseDriverObject<T: BaseObject>: Sync + Send + Sized { + /// Create a new driver data object for a GEM object of a given size. + fn new(dev: &drm::Device<T::Driver>, size: usize) -> impl PinInit<Self, Error>; + + /// Open a new handle to an existing object, associated with a File. + fn open( + _obj: &<<T as IntoGEMObject>::Driver as drm::Driver>::Object, + _file: &drm::File<<<T as IntoGEMObject>::Driver as drm::Driver>::File>, + ) -> Result { + Ok(()) + } + + /// Close a handle to an existing object, associated with a File. + fn close( + _obj: &<<T as IntoGEMObject>::Driver as drm::Driver>::Object, + _file: &drm::File<<<T as IntoGEMObject>::Driver as drm::Driver>::File>, + ) { + } +} + +/// Trait that represents a GEM object subtype +pub trait IntoGEMObject: Sized + super::private::Sealed + AlwaysRefCounted { + /// Owning driver for this type + type Driver: drm::Driver; + + /// Returns a reference to the raw `drm_gem_object` structure, which must be valid as long as + /// this owning object is valid. + fn as_raw(&self) -> *mut bindings::drm_gem_object; + + /// Converts a pointer to a `struct drm_gem_object` into a reference to `Self`. + /// + /// # Safety + /// + /// - `self_ptr` must be a valid pointer to `Self`. + /// - The caller promises that holding the immutable reference returned by this function does + /// not violate rust's data aliasing rules and remains valid throughout the lifetime of `'a`. + unsafe fn as_ref<'a>(self_ptr: *mut bindings::drm_gem_object) -> &'a Self; +} + +// SAFETY: All gem objects are refcounted. +unsafe impl<T: IntoGEMObject> AlwaysRefCounted for T { + fn inc_ref(&self) { + // SAFETY: The existence of a shared reference guarantees that the refcount is non-zero. + unsafe { bindings::drm_gem_object_get(self.as_raw()) }; + } + + unsafe fn dec_ref(obj: NonNull<Self>) { + // SAFETY: We either hold the only refcount on `obj`, or one of many - meaning that no one + // else could possibly hold a mutable reference to `obj` and thus this immutable reference + // is safe. + let obj = unsafe { obj.as_ref() }.as_raw(); + + // SAFETY: + // - The safety requirements guarantee that the refcount is non-zero. + // - We hold no references to `obj` now, making it safe for us to potentially deallocate it. + unsafe { bindings::drm_gem_object_put(obj) }; + } +} + +/// Trait which must be implemented by drivers using base GEM objects. +pub trait DriverObject: BaseDriverObject<Object<Self>> { + /// Parent `Driver` for this object. + type Driver: drm::Driver; +} + +extern "C" fn open_callback<T: BaseDriverObject<U>, U: BaseObject>( + raw_obj: *mut bindings::drm_gem_object, + raw_file: *mut bindings::drm_file, +) -> core::ffi::c_int { + // SAFETY: `open_callback` is only ever called with a valid pointer to a `struct drm_file`. + let file = unsafe { + drm::File::<<<U as IntoGEMObject>::Driver as drm::Driver>::File>::as_ref(raw_file) + }; + // SAFETY: `open_callback` is specified in the AllocOps structure for `Object<T>`, ensuring that + // `raw_obj` is indeed contained within a `Object<T>`. + let obj = unsafe { + <<<U as IntoGEMObject>::Driver as drm::Driver>::Object as IntoGEMObject>::as_ref(raw_obj) + }; + + match T::open(obj, file) { + Err(e) => e.to_errno(), + Ok(()) => 0, + } +} + +extern "C" fn close_callback<T: BaseDriverObject<U>, U: BaseObject>( + raw_obj: *mut bindings::drm_gem_object, + raw_file: *mut bindings::drm_file, +) { + // SAFETY: `open_callback` is only ever called with a valid pointer to a `struct drm_file`. + let file = unsafe { + drm::File::<<<U as IntoGEMObject>::Driver as drm::Driver>::File>::as_ref(raw_file) + }; + // SAFETY: `close_callback` is specified in the AllocOps structure for `Object<T>`, ensuring + // that `raw_obj` is indeed contained within a `Object<T>`. + let obj = unsafe { + <<<U as IntoGEMObject>::Driver as drm::Driver>::Object as IntoGEMObject>::as_ref(raw_obj) + }; + + T::close(obj, file); +} + +impl<T: DriverObject> IntoGEMObject for Object<T> { + type Driver = T::Driver; + + fn as_raw(&self) -> *mut bindings::drm_gem_object { + self.obj.get() + } + + unsafe fn as_ref<'a>(self_ptr: *mut bindings::drm_gem_object) -> &'a Self { + // SAFETY: `obj` is guaranteed to be in an `Object<T>` via the safety contract of this + // function + unsafe { &*crate::container_of!(self_ptr, Object<T>, obj) } + } +} + +/// Base operations shared by all GEM object classes +pub trait BaseObject: IntoGEMObject { + /// Returns the size of the object in bytes. + fn size(&self) -> usize { + // SAFETY: `self.as_raw()` is guaranteed to be a pointer to a valid `struct drm_gem_object`. + unsafe { (*self.as_raw()).size } + } + + /// Creates a new handle for the object associated with a given `File` + /// (or returns an existing one). + fn create_handle( + &self, + file: &drm::File<<<Self as IntoGEMObject>::Driver as drm::Driver>::File>, + ) -> Result<u32> { + let mut handle: u32 = 0; + // SAFETY: The arguments are all valid per the type invariants. + to_result(unsafe { + bindings::drm_gem_handle_create(file.as_raw().cast(), self.as_raw(), &mut handle) + })?; + Ok(handle) + } + + /// Looks up an object by its handle for a given `File`. + fn lookup_handle( + file: &drm::File<<<Self as IntoGEMObject>::Driver as drm::Driver>::File>, + handle: u32, + ) -> Result<ARef<Self>> { + // SAFETY: The arguments are all valid per the type invariants. + let ptr = unsafe { bindings::drm_gem_object_lookup(file.as_raw().cast(), handle) }; + if ptr.is_null() { + return Err(ENOENT); + } + + // SAFETY: + // - A `drm::Driver` can only have a single `File` implementation. + // - `file` uses the same `drm::Driver` as `Self`. + // - Therefore, we're guaranteed that `ptr` must be a gem object embedded within `Self`. + // - And we check if the pointer is null befoe calling as_ref(), ensuring that `ptr` is a + // valid pointer to an initialized `Self`. + let obj = unsafe { Self::as_ref(ptr) }; + + // SAFETY: + // - We take ownership of the reference of `drm_gem_object_lookup()`. + // - Our `NonNull` comes from an immutable reference, thus ensuring it is a valid pointer to + // `Self`. + Ok(unsafe { ARef::from_raw(obj.into()) }) + } + + /// Creates an mmap offset to map the object from userspace. + fn create_mmap_offset(&self) -> Result<u64> { + // SAFETY: The arguments are valid per the type invariant. + to_result(unsafe { bindings::drm_gem_create_mmap_offset(self.as_raw()) })?; + + // SAFETY: The arguments are valid per the type invariant. + Ok(unsafe { bindings::drm_vma_node_offset_addr(&raw mut (*self.as_raw()).vma_node) }) + } +} + +impl<T: IntoGEMObject> BaseObject for T {} + +/// A base GEM object. +/// +/// Invariants +/// +/// - `self.obj` is a valid instance of a `struct drm_gem_object`. +/// - `self.dev` is always a valid pointer to a `struct drm_device`. +#[repr(C)] +#[pin_data] +pub struct Object<T: DriverObject + Send + Sync> { + obj: Opaque<bindings::drm_gem_object>, + dev: NonNull<drm::Device<T::Driver>>, + #[pin] + data: T, +} + +impl<T: DriverObject> Object<T> { + /// The size of this object's structure. + pub const SIZE: usize = mem::size_of::<Self>(); + + const OBJECT_FUNCS: bindings::drm_gem_object_funcs = bindings::drm_gem_object_funcs { + free: Some(Self::free_callback), + open: Some(open_callback::<T, Object<T>>), + close: Some(close_callback::<T, Object<T>>), + print_info: None, + export: None, + pin: None, + unpin: None, + get_sg_table: None, + vmap: None, + vunmap: None, + mmap: None, + status: None, + vm_ops: core::ptr::null_mut(), + evict: None, + rss: None, + }; + + /// Create a new GEM object. + pub fn new(dev: &drm::Device<T::Driver>, size: usize) -> Result<ARef<Self>> { + let obj: Pin<KBox<Self>> = KBox::pin_init( + try_pin_init!(Self { + obj: Opaque::new(bindings::drm_gem_object::default()), + data <- T::new(dev, size), + // INVARIANT: The drm subsystem guarantees that the `struct drm_device` will live + // as long as the GEM object lives. + dev: dev.into(), + }), + GFP_KERNEL, + )?; + + // SAFETY: `obj.as_raw()` is guaranteed to be valid by the initialization above. + unsafe { (*obj.as_raw()).funcs = &Self::OBJECT_FUNCS }; + + // SAFETY: The arguments are all valid per the type invariants. + to_result(unsafe { bindings::drm_gem_object_init(dev.as_raw(), obj.obj.get(), size) })?; + + // SAFETY: We never move out of `Self`. + let ptr = KBox::into_raw(unsafe { Pin::into_inner_unchecked(obj) }); + + // SAFETY: `ptr` comes from `KBox::into_raw` and hence can't be NULL. + let ptr = unsafe { NonNull::new_unchecked(ptr) }; + + // SAFETY: We take over the initial reference count from `drm_gem_object_init()`. + Ok(unsafe { ARef::from_raw(ptr) }) + } + + /// Returns the `Device` that owns this GEM object. + pub fn dev(&self) -> &drm::Device<T::Driver> { + // SAFETY: The DRM subsystem guarantees that the `struct drm_device` will live as long as + // the GEM object lives, hence the pointer must be valid. + unsafe { self.dev.as_ref() } + } + + fn as_raw(&self) -> *mut bindings::drm_gem_object { + self.obj.get() + } + + extern "C" fn free_callback(obj: *mut bindings::drm_gem_object) { + // SAFETY: All of our objects are of type `Object<T>`. + let this = unsafe { crate::container_of!(obj, Self, obj) }.cast_mut(); + + // SAFETY: The C code only ever calls this callback with a valid pointer to a `struct + // drm_gem_object`. + unsafe { bindings::drm_gem_object_release(obj) }; + + // SAFETY: All of our objects are allocated via `KBox`, and we're in the + // free callback which guarantees this object has zero remaining references, + // so we can drop it. + let _ = unsafe { KBox::from_raw(this) }; + } +} + +impl<T: DriverObject> super::private::Sealed for Object<T> {} + +impl<T: DriverObject> Deref for Object<T> { + type Target = T; + + fn deref(&self) -> &Self::Target { + &self.data + } +} + +impl<T: DriverObject> AllocImpl for Object<T> { + const ALLOC_OPS: AllocOps = AllocOps { + gem_create_object: None, + prime_handle_to_fd: None, + prime_fd_to_handle: None, + gem_prime_import: None, + gem_prime_import_sg_table: None, + dumb_create: None, + dumb_map_offset: None, + }; +} + +pub(super) const fn create_fops() -> bindings::file_operations { + // SAFETY: As by the type invariant, it is safe to initialize `bindings::file_operations` + // zeroed. + let mut fops: bindings::file_operations = unsafe { core::mem::zeroed() }; + + fops.owner = core::ptr::null_mut(); + fops.open = Some(bindings::drm_open); + fops.release = Some(bindings::drm_release); + fops.unlocked_ioctl = Some(bindings::drm_ioctl); + #[cfg(CONFIG_COMPAT)] + { + fops.compat_ioctl = Some(bindings::drm_compat_ioctl); + } + fops.poll = Some(bindings::drm_poll); + fops.read = Some(bindings::drm_read); + fops.llseek = Some(bindings::noop_llseek); + fops.mmap = Some(bindings::drm_gem_mmap); + fops.fop_flags = bindings::FOP_UNSIGNED_OFFSET; + + fops +} diff --git a/rust/kernel/drm/ioctl.rs b/rust/kernel/drm/ioctl.rs new file mode 100644 index 000000000000..445639404fb7 --- /dev/null +++ b/rust/kernel/drm/ioctl.rs @@ -0,0 +1,162 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +//! DRM IOCTL definitions. +//! +//! C header: [`include/linux/drm/drm_ioctl.h`](srctree/include/linux/drm/drm_ioctl.h) + +use crate::ioctl; + +const BASE: u32 = uapi::DRM_IOCTL_BASE as u32; + +/// Construct a DRM ioctl number with no argument. +#[allow(non_snake_case)] +#[inline(always)] +pub const fn IO(nr: u32) -> u32 { + ioctl::_IO(BASE, nr) +} + +/// Construct a DRM ioctl number with a read-only argument. +#[allow(non_snake_case)] +#[inline(always)] +pub const fn IOR<T>(nr: u32) -> u32 { + ioctl::_IOR::<T>(BASE, nr) +} + +/// Construct a DRM ioctl number with a write-only argument. +#[allow(non_snake_case)] +#[inline(always)] +pub const fn IOW<T>(nr: u32) -> u32 { + ioctl::_IOW::<T>(BASE, nr) +} + +/// Construct a DRM ioctl number with a read-write argument. +#[allow(non_snake_case)] +#[inline(always)] +pub const fn IOWR<T>(nr: u32) -> u32 { + ioctl::_IOWR::<T>(BASE, nr) +} + +/// Descriptor type for DRM ioctls. Use the `declare_drm_ioctls!{}` macro to construct them. +pub type DrmIoctlDescriptor = bindings::drm_ioctl_desc; + +/// This is for ioctl which are used for rendering, and require that the file descriptor is either +/// for a render node, or if it’s a legacy/primary node, then it must be authenticated. +pub const AUTH: u32 = bindings::drm_ioctl_flags_DRM_AUTH; + +/// This must be set for any ioctl which can change the modeset or display state. Userspace must +/// call the ioctl through a primary node, while it is the active master. +/// +/// Note that read-only modeset ioctl can also be called by unauthenticated clients, or when a +/// master is not the currently active one. +pub const MASTER: u32 = bindings::drm_ioctl_flags_DRM_MASTER; + +/// Anything that could potentially wreak a master file descriptor needs to have this flag set. +/// +/// Current that’s only for the SETMASTER and DROPMASTER ioctl, which e.g. logind can call to +/// force a non-behaving master (display compositor) into compliance. +/// +/// This is equivalent to callers with the SYSADMIN capability. +pub const ROOT_ONLY: u32 = bindings::drm_ioctl_flags_DRM_ROOT_ONLY; + +/// This is used for all ioctl needed for rendering only, for drivers which support render nodes. +/// This should be all new render drivers, and hence it should be always set for any ioctl with +/// `AUTH` set. Note though that read-only query ioctl might have this set, but have not set +/// DRM_AUTH because they do not require authentication. +pub const RENDER_ALLOW: u32 = bindings::drm_ioctl_flags_DRM_RENDER_ALLOW; + +/// Internal structures used by the `declare_drm_ioctls!{}` macro. Do not use directly. +#[doc(hidden)] +pub mod internal { + pub use bindings::drm_device; + pub use bindings::drm_file; + pub use bindings::drm_ioctl_desc; +} + +/// Declare the DRM ioctls for a driver. +/// +/// Each entry in the list should have the form: +/// +/// `(ioctl_number, argument_type, flags, user_callback),` +/// +/// `argument_type` is the type name within the `bindings` crate. +/// `user_callback` should have the following prototype: +/// +/// ```ignore +/// fn foo(device: &kernel::drm::Device<Self>, +/// data: &Opaque<uapi::argument_type>, +/// file: &kernel::drm::File<Self::File>, +/// ) -> Result<u32> +/// ``` +/// where `Self` is the drm::drv::Driver implementation these ioctls are being declared within. +/// +/// # Examples +/// +/// ```ignore +/// kernel::declare_drm_ioctls! { +/// (FOO_GET_PARAM, drm_foo_get_param, ioctl::RENDER_ALLOW, my_get_param_handler), +/// } +/// ``` +/// +#[macro_export] +macro_rules! declare_drm_ioctls { + ( $(($cmd:ident, $struct:ident, $flags:expr, $func:expr)),* $(,)? ) => { + const IOCTLS: &'static [$crate::drm::ioctl::DrmIoctlDescriptor] = { + use $crate::uapi::*; + const _:() = { + let i: u32 = $crate::uapi::DRM_COMMAND_BASE; + // Assert that all the IOCTLs are in the right order and there are no gaps, + // and that the size of the specified type is correct. + $( + let cmd: u32 = $crate::macros::concat_idents!(DRM_IOCTL_, $cmd); + ::core::assert!(i == $crate::ioctl::_IOC_NR(cmd)); + ::core::assert!(core::mem::size_of::<$crate::uapi::$struct>() == + $crate::ioctl::_IOC_SIZE(cmd)); + let i: u32 = i + 1; + )* + }; + + let ioctls = &[$( + $crate::drm::ioctl::internal::drm_ioctl_desc { + cmd: $crate::macros::concat_idents!(DRM_IOCTL_, $cmd) as u32, + func: { + #[allow(non_snake_case)] + unsafe extern "C" fn $cmd( + raw_dev: *mut $crate::drm::ioctl::internal::drm_device, + raw_data: *mut ::core::ffi::c_void, + raw_file: *mut $crate::drm::ioctl::internal::drm_file, + ) -> core::ffi::c_int { + // SAFETY: + // - The DRM core ensures the device lives while callbacks are being + // called. + // - The DRM device must have been registered when we're called through + // an IOCTL. + // + // FIXME: Currently there is nothing enforcing that the types of the + // dev/file match the current driver these ioctls are being declared + // for, and it's not clear how to enforce this within the type system. + let dev = $crate::drm::device::Device::as_ref(raw_dev); + // SAFETY: The ioctl argument has size `_IOC_SIZE(cmd)`, which we + // asserted above matches the size of this type, and all bit patterns of + // UAPI structs must be valid. + let data = unsafe { + &*(raw_data as *const $crate::types::Opaque<$crate::uapi::$struct>) + }; + // SAFETY: This is just the DRM file structure + let file = unsafe { $crate::drm::File::as_ref(raw_file) }; + + match $func(dev, data, file) { + Err(e) => e.to_errno(), + Ok(i) => i.try_into() + .unwrap_or($crate::error::code::ERANGE.to_errno()), + } + } + Some($cmd) + }, + flags: $flags, + name: $crate::c_str!(::core::stringify!($cmd)).as_char_ptr(), + } + ),*]; + ioctls + }; + }; +} diff --git a/rust/kernel/drm/mod.rs b/rust/kernel/drm/mod.rs new file mode 100644 index 000000000000..1b82b6945edf --- /dev/null +++ b/rust/kernel/drm/mod.rs @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +//! DRM subsystem abstractions. + +pub mod device; +pub mod driver; +pub mod file; +pub mod gem; +pub mod ioctl; + +pub use self::device::Device; +pub use self::driver::Driver; +pub use self::driver::DriverInfo; +pub use self::driver::Registration; +pub use self::file::File; + +pub(crate) mod private { + pub trait Sealed {} +} diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs index de07aadd1ff5..ab0286857061 100644 --- a/rust/kernel/lib.rs +++ b/rust/kernel/lib.rs @@ -38,6 +38,8 @@ extern crate self as kernel; pub use ffi; pub mod alloc; +#[cfg(CONFIG_AUXILIARY_BUS)] +pub mod auxiliary; #[cfg(CONFIG_BLOCK)] pub mod block; #[doc(hidden)] @@ -48,6 +50,8 @@ pub mod device_id; pub mod devres; pub mod dma; pub mod driver; +#[cfg(CONFIG_DRM = "y")] +pub mod drm; pub mod error; pub mod faux; #[cfg(CONFIG_RUST_FW_LOADER_ABSTRACTIONS)] diff --git a/rust/kernel/pci.rs b/rust/kernel/pci.rs index c97d6d470b28..38fc8d5ffbf9 100644 --- a/rust/kernel/pci.rs +++ b/rust/kernel/pci.rs @@ -6,7 +6,7 @@ use crate::{ alloc::flags::*, - bindings, device, + bindings, container_of, device, device_id::RawDeviceId, devres::Devres, driver, @@ -360,11 +360,13 @@ impl<const SIZE: usize> Deref for Bar<SIZE> { } } -impl Device { +impl<Ctx: device::DeviceContext> Device<Ctx> { fn as_raw(&self) -> *mut bindings::pci_dev { self.0.get() } +} +impl Device { /// Returns the PCI vendor ID. pub fn vendor_id(&self) -> u16 { // SAFETY: `self.as_raw` is a valid pointer to a `struct pci_dev`. @@ -388,7 +390,9 @@ impl Device { // - by its type invariant `self.as_raw` is always a valid pointer to a `struct pci_dev`. Ok(unsafe { bindings::pci_resource_len(self.as_raw(), bar.try_into()?) }) } +} +impl Device<device::Bound> { /// Mapps an entire PCI-BAR after performing a region-request on it. I/O operation bound checks /// can be performed on compile time for offsets (plus the requested type size) < SIZE. pub fn iomap_region_sized<const SIZE: usize>( @@ -422,25 +426,10 @@ impl Device<device::Core> { } } -impl Deref for Device<device::Core> { - type Target = Device; - - fn deref(&self) -> &Self::Target { - let ptr: *const Self = self; - - // CAST: `Device<Ctx>` is a transparent wrapper of `Opaque<bindings::pci_dev>`. - let ptr = ptr.cast::<Device>(); - - // SAFETY: `ptr` was derived from `&self`. - unsafe { &*ptr } - } -} - -impl From<&Device<device::Core>> for ARef<Device> { - fn from(dev: &Device<device::Core>) -> Self { - (&**dev).into() - } -} +// SAFETY: `Device` is a transparent wrapper of a type that doesn't depend on `Device`'s generic +// argument. +kernel::impl_device_context_deref!(unsafe { Device }); +kernel::impl_device_context_into_aref!(Device); // SAFETY: Instances of `Device` are always reference-counted. unsafe impl crate::types::AlwaysRefCounted for Device { @@ -455,8 +444,8 @@ unsafe impl crate::types::AlwaysRefCounted for Device { } } -impl AsRef<device::Device> for Device { - fn as_ref(&self) -> &device::Device { +impl<Ctx: device::DeviceContext> AsRef<device::Device<Ctx>> for Device<Ctx> { + fn as_ref(&self) -> &device::Device<Ctx> { // SAFETY: By the type invariant of `Self`, `self.as_raw()` is a pointer to a valid // `struct pci_dev`. let dev = unsafe { addr_of_mut!((*self.as_raw()).dev) }; @@ -466,6 +455,26 @@ impl AsRef<device::Device> for Device { } } +impl<Ctx: device::DeviceContext> TryFrom<&device::Device<Ctx>> for &Device<Ctx> { + type Error = kernel::error::Error; + + fn try_from(dev: &device::Device<Ctx>) -> Result<Self, Self::Error> { + // SAFETY: By the type invariant of `Device`, `dev.as_raw()` is a valid pointer to a + // `struct device`. + if !unsafe { bindings::dev_is_pci(dev.as_raw()) } { + return Err(EINVAL); + } + + // SAFETY: We've just verified that the bus type of `dev` equals `bindings::pci_bus_type`, + // hence `dev` must be embedded in a valid `struct pci_dev` as guaranteed by the + // corresponding C code. + let pdev = unsafe { container_of!(dev.as_raw(), bindings::pci_dev, dev) }; + + // SAFETY: `pdev` is a valid pointer to a `struct pci_dev`. + Ok(unsafe { &*pdev.cast() }) + } +} + // SAFETY: A `Device` is always reference-counted and can be released from any thread. unsafe impl Send for Device {} diff --git a/rust/kernel/platform.rs b/rust/kernel/platform.rs index 4917cb34e2fe..08849d92c074 100644 --- a/rust/kernel/platform.rs +++ b/rust/kernel/platform.rs @@ -5,18 +5,17 @@ //! C header: [`include/linux/platform_device.h`](srctree/include/linux/platform_device.h) use crate::{ - bindings, device, driver, + bindings, container_of, device, driver, error::{to_result, Result}, of, prelude::*, str::CStr, - types::{ARef, ForeignOwnable, Opaque}, + types::{ForeignOwnable, Opaque}, ThisModule, }; use core::{ marker::PhantomData, - ops::Deref, ptr::{addr_of_mut, NonNull}, }; @@ -184,31 +183,16 @@ pub struct Device<Ctx: device::DeviceContext = device::Normal>( PhantomData<Ctx>, ); -impl Device { +impl<Ctx: device::DeviceContext> Device<Ctx> { fn as_raw(&self) -> *mut bindings::platform_device { self.0.get() } } -impl Deref for Device<device::Core> { - type Target = Device; - - fn deref(&self) -> &Self::Target { - let ptr: *const Self = self; - - // CAST: `Device<Ctx>` is a transparent wrapper of `Opaque<bindings::platform_device>`. - let ptr = ptr.cast::<Device>(); - - // SAFETY: `ptr` was derived from `&self`. - unsafe { &*ptr } - } -} - -impl From<&Device<device::Core>> for ARef<Device> { - fn from(dev: &Device<device::Core>) -> Self { - (&**dev).into() - } -} +// SAFETY: `Device` is a transparent wrapper of a type that doesn't depend on `Device`'s generic +// argument. +kernel::impl_device_context_deref!(unsafe { Device }); +kernel::impl_device_context_into_aref!(Device); // SAFETY: Instances of `Device` are always reference-counted. unsafe impl crate::types::AlwaysRefCounted for Device { @@ -223,8 +207,8 @@ unsafe impl crate::types::AlwaysRefCounted for Device { } } -impl AsRef<device::Device> for Device { - fn as_ref(&self) -> &device::Device { +impl<Ctx: device::DeviceContext> AsRef<device::Device<Ctx>> for Device<Ctx> { + fn as_ref(&self) -> &device::Device<Ctx> { // SAFETY: By the type invariant of `Self`, `self.as_raw()` is a pointer to a valid // `struct platform_device`. let dev = unsafe { addr_of_mut!((*self.as_raw()).dev) }; @@ -234,6 +218,26 @@ impl AsRef<device::Device> for Device { } } +impl<Ctx: device::DeviceContext> TryFrom<&device::Device<Ctx>> for &Device<Ctx> { + type Error = kernel::error::Error; + + fn try_from(dev: &device::Device<Ctx>) -> Result<Self, Self::Error> { + // SAFETY: By the type invariant of `Device`, `dev.as_raw()` is a valid pointer to a + // `struct device`. + if !unsafe { bindings::dev_is_platform(dev.as_raw()) } { + return Err(EINVAL); + } + + // SAFETY: We've just verified that the bus type of `dev` equals + // `bindings::platform_bus_type`, hence `dev` must be embedded in a valid + // `struct platform_device` as guaranteed by the corresponding C code. + let pdev = unsafe { container_of!(dev.as_raw(), bindings::platform_device, dev) }; + + // SAFETY: `pdev` is a valid pointer to a `struct platform_device`. + Ok(unsafe { &*pdev.cast() }) + } +} + // SAFETY: A `Device` is always reference-counted and can be released from any thread. unsafe impl Send for Device {} diff --git a/rust/kernel/revocable.rs b/rust/kernel/revocable.rs index 1e5a9d25c21b..db4aa46bb121 100644 --- a/rust/kernel/revocable.rs +++ b/rust/kernel/revocable.rs @@ -123,6 +123,34 @@ impl<T> Revocable<T> { } } + /// Tries to access the wrapped object and run a closure on it while the guard is held. + /// + /// This is a convenience method to run short non-sleepable code blocks while ensuring the + /// guard is dropped afterwards. [`Self::try_access`] carries the risk that the caller will + /// forget to explicitly drop that returned guard before calling sleepable code; this method + /// adds an extra safety to make sure it doesn't happen. + /// + /// Returns [`None`] if the object has been revoked and is therefore no longer accessible, or + /// the result of the closure wrapped in [`Some`]. If the closure returns a [`Result`] then the + /// return type becomes `Option<Result<>>`, which can be inconvenient. Users are encouraged to + /// define their own macro that turns the [`Option`] into a proper error code and flattens the + /// inner result into it if it makes sense within their subsystem. + pub fn try_access_with<R, F: FnOnce(&T) -> R>(&self, f: F) -> Option<R> { + self.try_access().map(|t| f(&*t)) + } + + /// Directly access the revocable wrapped object. + /// + /// # Safety + /// + /// The caller must ensure this [`Revocable`] instance hasn't been revoked and won't be revoked + /// as long as the returned `&T` lives. + pub unsafe fn access(&self) -> &T { + // SAFETY: By the safety requirement of this function it is guaranteed that + // `self.data.get()` is a valid pointer to an instance of `T`. + unsafe { &*self.data.get() } + } + /// # Safety /// /// Callers must ensure that there are no more concurrent users of the revocable object. diff --git a/rust/kernel/types.rs b/rust/kernel/types.rs index 9d0471afc964..eee387727d1a 100644 --- a/rust/kernel/types.rs +++ b/rust/kernel/types.rs @@ -329,6 +329,14 @@ impl<T> Opaque<T> { } } + /// Creates a new zeroed opaque value. + pub const fn zeroed() -> Self { + Self { + value: UnsafeCell::new(MaybeUninit::zeroed()), + _pin: PhantomPinned, + } + } + /// Create an opaque pin-initializer from the given pin-initializer. pub fn pin_init(slot: impl PinInit<T>) -> impl PinInit<Self> { Self::ffi_init(|ptr: *mut T| { diff --git a/rust/uapi/uapi_helper.h b/rust/uapi/uapi_helper.h index 76d3f103e764..1409441359f5 100644 --- a/rust/uapi/uapi_helper.h +++ b/rust/uapi/uapi_helper.h @@ -7,6 +7,8 @@ */ #include <uapi/asm-generic/ioctl.h> +#include <uapi/drm/drm.h> +#include <uapi/drm/nova_drm.h> #include <uapi/linux/mdio.h> #include <uapi/linux/mii.h> #include <uapi/linux/ethtool.h> diff --git a/samples/rust/Kconfig b/samples/rust/Kconfig index cad52b7120b5..b1006ab4bc3c 100644 --- a/samples/rust/Kconfig +++ b/samples/rust/Kconfig @@ -82,6 +82,18 @@ config SAMPLE_RUST_DRIVER_FAUX If unsure, say N. +config SAMPLE_RUST_DRIVER_AUXILIARY + tristate "Auxiliary Driver" + depends on PCI + select AUXILIARY_BUS + help + This option builds the Rust auxiliary driver sample. + + To compile this as a module, choose M here: + the module will be called rust_driver_auxiliary. + + If unsure, say N. + config SAMPLE_RUST_HOSTPROGS bool "Host programs" help diff --git a/samples/rust/Makefile b/samples/rust/Makefile index c6a2479f7d9c..6a466afd2a21 100644 --- a/samples/rust/Makefile +++ b/samples/rust/Makefile @@ -8,6 +8,7 @@ obj-$(CONFIG_SAMPLE_RUST_DMA) += rust_dma.o obj-$(CONFIG_SAMPLE_RUST_DRIVER_PCI) += rust_driver_pci.o obj-$(CONFIG_SAMPLE_RUST_DRIVER_PLATFORM) += rust_driver_platform.o obj-$(CONFIG_SAMPLE_RUST_DRIVER_FAUX) += rust_driver_faux.o +obj-$(CONFIG_SAMPLE_RUST_DRIVER_AUXILIARY) += rust_driver_auxiliary.o rust_print-y := rust_print_main.o rust_print_events.o diff --git a/samples/rust/rust_driver_auxiliary.rs b/samples/rust/rust_driver_auxiliary.rs new file mode 100644 index 000000000000..3e15e6d002bb --- /dev/null +++ b/samples/rust/rust_driver_auxiliary.rs @@ -0,0 +1,120 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! Rust auxiliary driver sample (based on a PCI driver for QEMU's `pci-testdev`). +//! +//! To make this driver probe, QEMU must be run with `-device pci-testdev`. + +use kernel::{ + auxiliary, bindings, c_str, device::Core, driver, error::Error, pci, prelude::*, str::CStr, + InPlaceModule, +}; + +use pin_init::PinInit; + +const MODULE_NAME: &CStr = <LocalModule as kernel::ModuleMetadata>::NAME; +const AUXILIARY_NAME: &CStr = c_str!("auxiliary"); + +struct AuxiliaryDriver; + +kernel::auxiliary_device_table!( + AUX_TABLE, + MODULE_AUX_TABLE, + <AuxiliaryDriver as auxiliary::Driver>::IdInfo, + [(auxiliary::DeviceId::new(MODULE_NAME, AUXILIARY_NAME), ())] +); + +impl auxiliary::Driver for AuxiliaryDriver { + type IdInfo = (); + + const ID_TABLE: auxiliary::IdTable<Self::IdInfo> = &AUX_TABLE; + + fn probe(adev: &auxiliary::Device<Core>, _info: &Self::IdInfo) -> Result<Pin<KBox<Self>>> { + dev_info!( + adev.as_ref(), + "Probing auxiliary driver for auxiliary device with id={}\n", + adev.id() + ); + + ParentDriver::connect(adev)?; + + let this = KBox::new(Self, GFP_KERNEL)?; + + Ok(this.into()) + } +} + +struct ParentDriver { + _reg: [auxiliary::Registration; 2], +} + +kernel::pci_device_table!( + PCI_TABLE, + MODULE_PCI_TABLE, + <ParentDriver as pci::Driver>::IdInfo, + [( + pci::DeviceId::from_id(bindings::PCI_VENDOR_ID_REDHAT, 0x5), + () + )] +); + +impl pci::Driver for ParentDriver { + type IdInfo = (); + + const ID_TABLE: pci::IdTable<Self::IdInfo> = &PCI_TABLE; + + fn probe(pdev: &pci::Device<Core>, _info: &Self::IdInfo) -> Result<Pin<KBox<Self>>> { + let this = KBox::new( + Self { + _reg: [ + auxiliary::Registration::new(pdev.as_ref(), AUXILIARY_NAME, 0, MODULE_NAME)?, + auxiliary::Registration::new(pdev.as_ref(), AUXILIARY_NAME, 1, MODULE_NAME)?, + ], + }, + GFP_KERNEL, + )?; + + Ok(this.into()) + } +} + +impl ParentDriver { + fn connect(adev: &auxiliary::Device) -> Result<()> { + let parent = adev.parent().ok_or(EINVAL)?; + let pdev: &pci::Device = parent.try_into()?; + + dev_info!( + adev.as_ref(), + "Connect auxiliary {} with parent: VendorID={:#x}, DeviceID={:#x}\n", + adev.id(), + pdev.vendor_id(), + pdev.device_id() + ); + + Ok(()) + } +} + +#[pin_data] +struct SampleModule { + #[pin] + _pci_driver: driver::Registration<pci::Adapter<ParentDriver>>, + #[pin] + _aux_driver: driver::Registration<auxiliary::Adapter<AuxiliaryDriver>>, +} + +impl InPlaceModule for SampleModule { + fn init(module: &'static kernel::ThisModule) -> impl PinInit<Self, Error> { + try_pin_init!(Self { + _pci_driver <- driver::Registration::new(MODULE_NAME, module), + _aux_driver <- driver::Registration::new(MODULE_NAME, module), + }) + } +} + +module! { + type: SampleModule, + name: "rust_driver_auxiliary", + author: "Danilo Krummrich", + description: "Rust auxiliary driver", + license: "GPL v2", +} diff --git a/samples/rust/rust_driver_pci.rs b/samples/rust/rust_driver_pci.rs index 2bb260aebc9e..15147e4401b2 100644 --- a/samples/rust/rust_driver_pci.rs +++ b/samples/rust/rust_driver_pci.rs @@ -83,12 +83,11 @@ impl pci::Driver for SampleDriver { GFP_KERNEL, )?; - let bar = drvdata.bar.try_access().ok_or(ENXIO)?; - + let bar = drvdata.bar.access(pdev.as_ref())?; dev_info!( pdev.as_ref(), "pci-testdev data-match count: {}\n", - Self::testdev(info, &bar)? + Self::testdev(info, bar)? ); Ok(drvdata.into()) |