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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
| commit | f4cdf7ca9a1fdcca413157df19753f388a5a224e (patch) | |
| tree | 60a31895b2446cd7fa27514e8c2843534a0de0da /rust/macros/vtable.rs | |
| download | linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip | |
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab:
- v4l2-core: added ISP statistics support and per-block validation
- v4l2-core: Allow unknown HDR10 white point and luminance
- New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor
- New codec: Milos: VPU v2.0 codec support
- isp driver: gained support for Dreamchip RPPX1 ISP framework
- vsp1 driver: gained support for RZ/T2H and RZ/N2H
- Novalake driver: gained CVS support for new NVL hardware
- dvb-core: fix feed leak on failed DMX_ADD_PID
- several driver fixes, cleanups and minor improvements
* tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits)
media: ipu-bridge: check all DMI entries when overriding sensor rotation
media: v4l2-async: avoid deleting unlinked ASC entry on link error
media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement
media: intel/ipu6: fix async notifier cleanup leak on parse error
media: staging/ipu7: fix async notifier UAF on probe error path
media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path
media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem()
media: rcar-isp: Fix VSPX reference leaks
media: rcar-isp: Release ISPCORE resources
media: i2c: imx415: Release runtime PM reference on VBLANK error
media: i2c: imx415: Return test pattern write errors
media: renesas: vsp1: Declare index variables in for loop statement
media: renesas: vsp1: Make reset control optional to support platforms without a reset line
media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs
media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs
media: nxp: imx8-isi: Add additional 32-bit RGB format support
media: nxp: imx8-isi: Add 16-bit raw Bayer format support
media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams
media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks
media: nxp: imx8-isi: Correct color map between V4L2 and ISI
...
Diffstat (limited to 'rust/macros/vtable.rs')
| -rw-r--r-- | rust/macros/vtable.rs | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/rust/macros/vtable.rs b/rust/macros/vtable.rs new file mode 100644 index 000000000..be9a5ed8a --- /dev/null +++ b/rust/macros/vtable.rs @@ -0,0 +1,136 @@ +// SPDX-License-Identifier: GPL-2.0 + +use std::{ + collections::HashSet, + iter::Extend, // +}; + +use proc_macro2::{ + Ident, + TokenStream, // +}; +use quote::ToTokens; +use syn::{ + parse_quote, + Error, + ImplItem, + Item, + ItemImpl, + ItemTrait, + Result, + TraitItem, // +}; + +fn handle_trait(mut item: ItemTrait) -> Result<ItemTrait> { + let mut gen_items = Vec::new(); + + gen_items.push(parse_quote! { + /// A marker to prevent implementors from forgetting to use [`#[vtable]`](vtable) + /// attribute when implementing this trait. + const USE_VTABLE_ATTR: (); + }); + + // Add `type OwnerModule: ModuleMetadata` as a required associated type if + // the trait does not already define it. + if !item + .items + .iter() + .any(|i| matches!(i, TraitItem::Type(t) if t.ident == "OwnerModule")) + { + gen_items.push(parse_quote! { + /// The module implementing this vtable trait. + /// + /// Automatically set to `crate::LocalModule` by the `#[vtable]` + /// impl macro. + type OwnerModule: ::kernel::ModuleMetadata; + }); + } + + for item in &item.items { + if let TraitItem::Fn(fn_item) = item { + let name = &fn_item.sig.ident; + let gen_const_name = Ident::new( + &format!("HAS_{}", name.to_string().to_uppercase()), + name.span(), + ); + + // We don't know on the implementation-site whether a method is required or provided + // so we have to generate a const for all methods. + let cfg_attrs = crate::helpers::gather_cfg_attrs(&fn_item.attrs); + let comment = + format!("Indicates if the `{name}` method is overridden by the implementor."); + gen_items.push(parse_quote! { + #(#cfg_attrs)* + #[doc = #comment] + const #gen_const_name: bool = false; + }); + } + } + + item.items.extend(gen_items); + Ok(item) +} + +fn handle_impl(mut item: ItemImpl) -> Result<ItemImpl> { + let mut gen_items = Vec::new(); + let mut defined_items = HashSet::new(); + + // Iterate over all user-defined items to gather any possible explicit overrides. + for item in &item.items { + match item { + ImplItem::Const(const_item) => { + defined_items.insert(const_item.ident.clone()); + } + ImplItem::Type(type_item) => { + defined_items.insert(type_item.ident.clone()); + } + _ => {} + } + } + + gen_items.push(parse_quote! { + const USE_VTABLE_ATTR: () = (); + }); + + // Auto-insert `type OwnerModule = crate::LocalModule` if not explicitly defined. + // `crate::LocalModule` resolves to the real module type (via `module!`) or a + // dummy fallback in non-module contexts (e.g., doctests). + if !defined_items.contains(&parse_quote!(OwnerModule)) { + gen_items.push(parse_quote! { + type OwnerModule = crate::LocalModule; + }); + } + + for item in &item.items { + if let ImplItem::Fn(fn_item) = item { + let name = &fn_item.sig.ident; + let gen_const_name = Ident::new( + &format!("HAS_{}", name.to_string().to_uppercase()), + name.span(), + ); + // Skip if it's declared already -- this allows user override. + if defined_items.contains(&gen_const_name) { + continue; + } + let cfg_attrs = crate::helpers::gather_cfg_attrs(&fn_item.attrs); + gen_items.push(parse_quote! { + #(#cfg_attrs)* + const #gen_const_name: bool = true; + }); + } + } + + item.items.extend(gen_items); + Ok(item) +} + +pub(crate) fn vtable(input: Item) -> Result<TokenStream> { + match input { + Item::Trait(item) => Ok(handle_trait(item)?.into_token_stream()), + Item::Impl(item) => Ok(handle_impl(item)?.into_token_stream()), + _ => Err(Error::new_spanned( + input, + "`#[vtable]` attribute should only be applied to trait or impl block", + ))?, + } +} |
