From db4f72c904cb116e2bf56afdd67fc5167a607a7b Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Wed, 4 Sep 2024 22:43:32 +0200 Subject: rust: enable `clippy::undocumented_unsafe_blocks` lint Checking that we are not missing any `// SAFETY` comments in our `unsafe` blocks is something we have wanted to do for a long time, as well as cleaning up the remaining cases that were not documented [1]. Back when Rust for Linux started, this was something that could have been done via a script, like Rust's `tidy`. Soon after, in Rust 1.58.0, Clippy implemented the `undocumented_unsafe_blocks` lint [2]. Even though the lint has a few false positives, e.g. in some cases where attributes appear between the comment and the `unsafe` block [3], there are workarounds and the lint seems quite usable already. Thus enable the lint now. We still have a few cases to clean up, so just allow those for the moment by writing a `TODO` comment -- some of those may be good candidates for new contributors. Link: https://github.com/Rust-for-Linux/linux/issues/351 [1] Link: https://rust-lang.github.io/rust-clippy/master/#/undocumented_unsafe_blocks [2] Link: https://github.com/rust-lang/rust-clippy/issues/13189 [3] Reviewed-by: Alice Ryhl Reviewed-by: Trevor Gross Tested-by: Gary Guo Reviewed-by: Gary Guo Link: https://lore.kernel.org/r/20240904204347.168520-5-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- rust/kernel/alloc/allocator.rs | 2 ++ 1 file changed, 2 insertions(+) (limited to 'rust/kernel/alloc/allocator.rs') diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs index e6ea601f38c6..91216b36af69 100644 --- a/rust/kernel/alloc/allocator.rs +++ b/rust/kernel/alloc/allocator.rs @@ -31,6 +31,7 @@ pub(crate) unsafe fn krealloc_aligned(ptr: *mut u8, new_layout: Layout, flags: F unsafe { bindings::krealloc(ptr as *const core::ffi::c_void, size, flags.0) as *mut u8 } } +// SAFETY: TODO. unsafe impl GlobalAlloc for KernelAllocator { unsafe fn alloc(&self, layout: Layout) -> *mut u8 { // SAFETY: `ptr::null_mut()` is null and `layout` has a non-zero size by the function safety @@ -39,6 +40,7 @@ unsafe impl GlobalAlloc for KernelAllocator { } unsafe fn dealloc(&self, ptr: *mut u8, _layout: Layout) { + // SAFETY: TODO. unsafe { bindings::kfree(ptr as *const core::ffi::c_void); } -- cgit v1.2.3 From a654a6e09644266e38ac05415ef7737d299c4497 Mon Sep 17 00:00:00 2001 From: Danilo Krummrich Date: Fri, 4 Oct 2024 17:41:06 +0200 Subject: rust: alloc: separate `aligned_size` from `krealloc_aligned` Separate `aligned_size` from `krealloc_aligned`. Subsequent patches implement `Allocator` derivates, such as `Kmalloc`, that require `aligned_size` and replace the original `krealloc_aligned`. Reviewed-by: Alice Ryhl Reviewed-by: Benno Lossin Reviewed-by: Gary Guo Signed-off-by: Danilo Krummrich Link: https://lore.kernel.org/r/20241004154149.93856-3-dakr@kernel.org Signed-off-by: Miguel Ojeda --- rust/kernel/alloc/allocator.rs | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) (limited to 'rust/kernel/alloc/allocator.rs') diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs index 91216b36af69..765f72d5bc21 100644 --- a/rust/kernel/alloc/allocator.rs +++ b/rust/kernel/alloc/allocator.rs @@ -8,6 +8,17 @@ use core::ptr; struct KernelAllocator; +/// Returns a proper size to alloc a new object aligned to `new_layout`'s alignment. +fn aligned_size(new_layout: Layout) -> usize { + // Customized layouts from `Layout::from_size_align()` can have size < align, so pad first. + let layout = new_layout.pad_to_align(); + + // Note that `layout.size()` (after padding) is guaranteed to be a multiple of `layout.align()` + // which together with the slab guarantees means the `krealloc` will return a properly aligned + // object (see comments in `kmalloc()` for more information). + layout.size() +} + /// Calls `krealloc` with a proper size to alloc a new object aligned to `new_layout`'s alignment. /// /// # Safety @@ -15,13 +26,7 @@ struct KernelAllocator; /// - `ptr` can be either null or a pointer which has been allocated by this allocator. /// - `new_layout` must have a non-zero size. pub(crate) unsafe fn krealloc_aligned(ptr: *mut u8, new_layout: Layout, flags: Flags) -> *mut u8 { - // Customized layouts from `Layout::from_size_align()` can have size < align, so pad first. - let layout = new_layout.pad_to_align(); - - // Note that `layout.size()` (after padding) is guaranteed to be a multiple of `layout.align()` - // which together with the slab guarantees means the `krealloc` will return a properly aligned - // object (see comments in `kmalloc()` for more information). - let size = layout.size(); + let size = aligned_size(new_layout); // SAFETY: // - `ptr` is either null or a pointer returned from a previous `k{re}alloc()` by the -- cgit v1.2.3 From 941e65531446c1eb5d573c5d30172117ebe96112 Mon Sep 17 00:00:00 2001 From: Danilo Krummrich Date: Fri, 4 Oct 2024 17:41:07 +0200 Subject: rust: alloc: rename `KernelAllocator` to `Kmalloc` Subsequent patches implement `Vmalloc` and `KVmalloc` allocators, hence align `KernelAllocator` to this naming scheme. Reviewed-by: Alice Ryhl Reviewed-by: Benno Lossin Reviewed-by: Gary Guo Signed-off-by: Danilo Krummrich Link: https://lore.kernel.org/r/20241004154149.93856-4-dakr@kernel.org Signed-off-by: Miguel Ojeda --- rust/kernel/alloc/allocator.rs | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'rust/kernel/alloc/allocator.rs') diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs index 765f72d5bc21..3b1c735ba409 100644 --- a/rust/kernel/alloc/allocator.rs +++ b/rust/kernel/alloc/allocator.rs @@ -6,7 +6,7 @@ use super::{flags::*, Flags}; use core::alloc::{GlobalAlloc, Layout}; use core::ptr; -struct KernelAllocator; +struct Kmalloc; /// Returns a proper size to alloc a new object aligned to `new_layout`'s alignment. fn aligned_size(new_layout: Layout) -> usize { @@ -37,7 +37,7 @@ pub(crate) unsafe fn krealloc_aligned(ptr: *mut u8, new_layout: Layout, flags: F } // SAFETY: TODO. -unsafe impl GlobalAlloc for KernelAllocator { +unsafe impl GlobalAlloc for Kmalloc { unsafe fn alloc(&self, layout: Layout) -> *mut u8 { // SAFETY: `ptr::null_mut()` is null and `layout` has a non-zero size by the function safety // requirement. @@ -74,7 +74,7 @@ unsafe impl GlobalAlloc for KernelAllocator { } #[global_allocator] -static ALLOCATOR: KernelAllocator = KernelAllocator; +static ALLOCATOR: Kmalloc = Kmalloc; // See . #[no_mangle] -- cgit v1.2.3 From 8a799831fc63c988eec90d334fdd68ff5f2c7eb5 Mon Sep 17 00:00:00 2001 From: Danilo Krummrich Date: Fri, 4 Oct 2024 17:41:08 +0200 Subject: rust: alloc: implement `ReallocFunc` `ReallocFunc` is an abstraction for the kernel's realloc derivates, such as `krealloc`, `vrealloc` and `kvrealloc`. All of the named functions share the same function signature and implement the same semantics. The `ReallocFunc` abstractions provides a generalized wrapper around those, to trivialize the implementation of `Kmalloc`, `Vmalloc` and `KVmalloc` in subsequent patches. Reviewed-by: Benno Lossin Reviewed-by: Gary Guo Signed-off-by: Danilo Krummrich Link: https://lore.kernel.org/r/20241004154149.93856-5-dakr@kernel.org [ Added temporary `allow(dead_code)` for `dangling_from_layout` to clean warning in `rusttest` target as discussed in the list (but it is needed earlier, i.e. in this patch already). Added colon. - Miguel ] Signed-off-by: Miguel Ojeda --- rust/kernel/alloc.rs | 9 ++++++ rust/kernel/alloc/allocator.rs | 70 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 79 insertions(+) (limited to 'rust/kernel/alloc/allocator.rs') diff --git a/rust/kernel/alloc.rs b/rust/kernel/alloc.rs index 998779cc6976..95d402feb6ff 100644 --- a/rust/kernel/alloc.rs +++ b/rust/kernel/alloc.rs @@ -187,3 +187,12 @@ pub unsafe trait Allocator { let _ = unsafe { Self::realloc(Some(ptr), Layout::new::<()>(), layout, Flags(0)) }; } } + +#[allow(dead_code)] +/// Returns a properly aligned dangling pointer from the given `layout`. +pub(crate) fn dangling_from_layout(layout: Layout) -> NonNull { + let ptr = layout.align() as *mut u8; + + // SAFETY: `layout.align()` (and hence `ptr`) is guaranteed to be non-zero. + unsafe { NonNull::new_unchecked(ptr) } +} diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs index 3b1c735ba409..9ed122401e8a 100644 --- a/rust/kernel/alloc/allocator.rs +++ b/rust/kernel/alloc/allocator.rs @@ -1,10 +1,20 @@ // SPDX-License-Identifier: GPL-2.0 //! Allocator support. +//! +//! Documentation for the kernel's memory allocators can found in the "Memory Allocation Guide" +//! linked below. For instance, this includes the concept of "get free page" (GFP) flags and the +//! typical application of the different kernel allocators. +//! +//! Reference: use super::{flags::*, Flags}; use core::alloc::{GlobalAlloc, Layout}; use core::ptr; +use core::ptr::NonNull; + +use crate::alloc::AllocError; +use crate::bindings; struct Kmalloc; @@ -36,6 +46,66 @@ pub(crate) unsafe fn krealloc_aligned(ptr: *mut u8, new_layout: Layout, flags: F unsafe { bindings::krealloc(ptr as *const core::ffi::c_void, size, flags.0) as *mut u8 } } +/// # Invariants +/// +/// One of the following: `krealloc`, `vrealloc`, `kvrealloc`. +struct ReallocFunc( + unsafe extern "C" fn(*const core::ffi::c_void, usize, u32) -> *mut core::ffi::c_void, +); + +#[expect(dead_code)] +impl ReallocFunc { + /// # Safety + /// + /// This method has the same safety requirements as [`Allocator::realloc`]. + /// + /// # Guarantees + /// + /// This method has the same guarantees as `Allocator::realloc`. Additionally + /// - it accepts any pointer to a valid memory allocation allocated by this function. + /// - memory allocated by this function remains valid until it is passed to this function. + unsafe fn call( + &self, + ptr: Option>, + layout: Layout, + old_layout: Layout, + flags: Flags, + ) -> Result, AllocError> { + let size = aligned_size(layout); + let ptr = match ptr { + Some(ptr) => { + if old_layout.size() == 0 { + ptr::null() + } else { + ptr.as_ptr() + } + } + None => ptr::null(), + }; + + // SAFETY: + // - `self.0` is one of `krealloc`, `vrealloc`, `kvrealloc` and thus only requires that + // `ptr` is NULL or valid. + // - `ptr` is either NULL or valid by the safety requirements of this function. + // + // GUARANTEE: + // - `self.0` is one of `krealloc`, `vrealloc`, `kvrealloc`. + // - Those functions provide the guarantees of this function. + let raw_ptr = unsafe { + // If `size == 0` and `ptr != NULL` the memory behind the pointer is freed. + self.0(ptr.cast(), size, flags.0).cast() + }; + + let ptr = if size == 0 { + crate::alloc::dangling_from_layout(layout) + } else { + NonNull::new(raw_ptr).ok_or(AllocError)? + }; + + Ok(NonNull::slice_from_raw_parts(ptr, size)) + } +} + // SAFETY: TODO. unsafe impl GlobalAlloc for Kmalloc { unsafe fn alloc(&self, layout: Layout) -> *mut u8 { -- cgit v1.2.3 From a34822d1c4c93085f635b922441a017bd7e959b0 Mon Sep 17 00:00:00 2001 From: Danilo Krummrich Date: Fri, 4 Oct 2024 17:41:10 +0200 Subject: rust: alloc: implement `Allocator` for `Kmalloc` Implement `Allocator` for `Kmalloc`, the kernel's default allocator, typically used for objects smaller than page size. All memory allocations made with `Kmalloc` end up in `krealloc()`. It serves as allocator for the subsequently introduced types `KBox` and `KVec`. Reviewed-by: Benno Lossin Reviewed-by: Gary Guo Signed-off-by: Danilo Krummrich Link: https://lore.kernel.org/r/20241004154149.93856-7-dakr@kernel.org Signed-off-by: Miguel Ojeda --- rust/kernel/alloc/allocator.rs | 31 ++++++++++++++++++++++++++++--- 1 file changed, 28 insertions(+), 3 deletions(-) (limited to 'rust/kernel/alloc/allocator.rs') diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs index 9ed122401e8a..272c581e24a0 100644 --- a/rust/kernel/alloc/allocator.rs +++ b/rust/kernel/alloc/allocator.rs @@ -13,10 +13,16 @@ use core::alloc::{GlobalAlloc, Layout}; use core::ptr; use core::ptr::NonNull; -use crate::alloc::AllocError; +use crate::alloc::{AllocError, Allocator}; use crate::bindings; -struct Kmalloc; +/// The contiguous kernel allocator. +/// +/// `Kmalloc` is typically used for physically contiguous allocations up to page size, but also +/// supports larger allocations up to `bindings::KMALLOC_MAX_SIZE`, which is hardware specific. +/// +/// For more details see [self]. +pub struct Kmalloc; /// Returns a proper size to alloc a new object aligned to `new_layout`'s alignment. fn aligned_size(new_layout: Layout) -> usize { @@ -53,8 +59,10 @@ struct ReallocFunc( unsafe extern "C" fn(*const core::ffi::c_void, usize, u32) -> *mut core::ffi::c_void, ); -#[expect(dead_code)] impl ReallocFunc { + // INVARIANT: `krealloc` satisfies the type invariants. + const KREALLOC: Self = Self(bindings::krealloc); + /// # Safety /// /// This method has the same safety requirements as [`Allocator::realloc`]. @@ -106,6 +114,23 @@ impl ReallocFunc { } } +// SAFETY: `realloc` delegates to `ReallocFunc::call`, which guarantees that +// - memory remains valid until it is explicitly freed, +// - passing a pointer to a valid memory allocation is OK, +// - `realloc` satisfies the guarantees, since `ReallocFunc::call` has the same. +unsafe impl Allocator for Kmalloc { + #[inline] + unsafe fn realloc( + ptr: Option>, + layout: Layout, + old_layout: Layout, + flags: Flags, + ) -> Result, AllocError> { + // SAFETY: `ReallocFunc::call` has the same safety requirements as `Allocator::realloc`. + unsafe { ReallocFunc::KREALLOC.call(ptr, layout, old_layout, flags) } + } +} + // SAFETY: TODO. unsafe impl GlobalAlloc for Kmalloc { unsafe fn alloc(&self, layout: Layout) -> *mut u8 { -- cgit v1.2.3 From 61c004781d6b928443052e7a6cf84b35d4f61401 Mon Sep 17 00:00:00 2001 From: Danilo Krummrich Date: Fri, 4 Oct 2024 17:41:12 +0200 Subject: rust: alloc: implement `Vmalloc` allocator Implement `Allocator` for `Vmalloc`, the kernel's virtually contiguous allocator, typically used for larger objects, (much) larger than page size. All memory allocations made with `Vmalloc` end up in `vrealloc()`. Reviewed-by: Alice Ryhl Reviewed-by: Benno Lossin Reviewed-by: Gary Guo Signed-off-by: Danilo Krummrich Link: https://lore.kernel.org/r/20241004154149.93856-9-dakr@kernel.org Signed-off-by: Miguel Ojeda --- rust/helpers/helpers.c | 1 + rust/helpers/vmalloc.c | 9 +++++++++ rust/kernel/alloc/allocator.rs | 37 +++++++++++++++++++++++++++++++++++++ rust/kernel/alloc/allocator_test.rs | 1 + 4 files changed, 48 insertions(+) create mode 100644 rust/helpers/vmalloc.c (limited to 'rust/kernel/alloc/allocator.rs') diff --git a/rust/helpers/helpers.c b/rust/helpers/helpers.c index 30f40149f3a9..20a0c69d5cc7 100644 --- a/rust/helpers/helpers.c +++ b/rust/helpers/helpers.c @@ -22,5 +22,6 @@ #include "spinlock.c" #include "task.c" #include "uaccess.c" +#include "vmalloc.c" #include "wait.c" #include "workqueue.c" diff --git a/rust/helpers/vmalloc.c b/rust/helpers/vmalloc.c new file mode 100644 index 000000000000..80d34501bbc0 --- /dev/null +++ b/rust/helpers/vmalloc.c @@ -0,0 +1,9 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include + +void * __must_check __realloc_size(2) +rust_helper_vrealloc(const void *p, size_t size, gfp_t flags) +{ + return vrealloc(p, size, flags); +} diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs index 272c581e24a0..ee4c828cbd58 100644 --- a/rust/kernel/alloc/allocator.rs +++ b/rust/kernel/alloc/allocator.rs @@ -15,6 +15,7 @@ use core::ptr::NonNull; use crate::alloc::{AllocError, Allocator}; use crate::bindings; +use crate::pr_warn; /// The contiguous kernel allocator. /// @@ -24,6 +25,15 @@ use crate::bindings; /// For more details see [self]. pub struct Kmalloc; +/// The virtually contiguous kernel allocator. +/// +/// `Vmalloc` allocates pages from the page level allocator and maps them into the contiguous kernel +/// virtual space. It is typically used for large allocations. The memory allocated with this +/// allocator is not physically contiguous. +/// +/// For more details see [self]. +pub struct Vmalloc; + /// Returns a proper size to alloc a new object aligned to `new_layout`'s alignment. fn aligned_size(new_layout: Layout) -> usize { // Customized layouts from `Layout::from_size_align()` can have size < align, so pad first. @@ -63,6 +73,9 @@ impl ReallocFunc { // INVARIANT: `krealloc` satisfies the type invariants. const KREALLOC: Self = Self(bindings::krealloc); + // INVARIANT: `vrealloc` satisfies the type invariants. + const VREALLOC: Self = Self(bindings::vrealloc); + /// # Safety /// /// This method has the same safety requirements as [`Allocator::realloc`]. @@ -168,6 +181,30 @@ unsafe impl GlobalAlloc for Kmalloc { } } +// SAFETY: `realloc` delegates to `ReallocFunc::call`, which guarantees that +// - memory remains valid until it is explicitly freed, +// - passing a pointer to a valid memory allocation is OK, +// - `realloc` satisfies the guarantees, since `ReallocFunc::call` has the same. +unsafe impl Allocator for Vmalloc { + #[inline] + unsafe fn realloc( + ptr: Option>, + layout: Layout, + old_layout: Layout, + flags: Flags, + ) -> Result, AllocError> { + // TODO: Support alignments larger than PAGE_SIZE. + if layout.align() > bindings::PAGE_SIZE { + pr_warn!("Vmalloc does not support alignments larger than PAGE_SIZE yet.\n"); + return Err(AllocError); + } + + // SAFETY: If not `None`, `ptr` is guaranteed to point to valid memory, which was previously + // allocated with this `Allocator`. + unsafe { ReallocFunc::VREALLOC.call(ptr, layout, old_layout, flags) } + } +} + #[global_allocator] static ALLOCATOR: Kmalloc = Kmalloc; diff --git a/rust/kernel/alloc/allocator_test.rs b/rust/kernel/alloc/allocator_test.rs index c5d325506f0c..32a1450c4d39 100644 --- a/rust/kernel/alloc/allocator_test.rs +++ b/rust/kernel/alloc/allocator_test.rs @@ -7,6 +7,7 @@ use core::alloc::Layout; use core::ptr::NonNull; pub struct Kmalloc; +pub type Vmalloc = Kmalloc; unsafe impl Allocator for Kmalloc { unsafe fn realloc( -- cgit v1.2.3 From 8362c2608ba1be635ffa22a256dfcfe51c6238cc Mon Sep 17 00:00:00 2001 From: Danilo Krummrich Date: Fri, 4 Oct 2024 17:41:13 +0200 Subject: rust: alloc: implement `KVmalloc` allocator Implement `Allocator` for `KVmalloc`, an `Allocator` that tries to allocate memory with `kmalloc` first and, on failure, falls back to `vmalloc`. All memory allocations made with `KVmalloc` end up in `kvrealloc_noprof()`; all frees in `kvfree()`. Reviewed-by: Alice Ryhl Reviewed-by: Benno Lossin Reviewed-by: Gary Guo Signed-off-by: Danilo Krummrich Link: https://lore.kernel.org/r/20241004154149.93856-10-dakr@kernel.org [ Reworded typo. - Miguel ] Signed-off-by: Miguel Ojeda --- rust/helpers/slab.c | 6 ++++++ rust/kernel/alloc/allocator.rs | 36 ++++++++++++++++++++++++++++++++++++ rust/kernel/alloc/allocator_test.rs | 1 + 3 files changed, 43 insertions(+) (limited to 'rust/kernel/alloc/allocator.rs') diff --git a/rust/helpers/slab.c b/rust/helpers/slab.c index f043e087f9d6..a842bfbddcba 100644 --- a/rust/helpers/slab.c +++ b/rust/helpers/slab.c @@ -7,3 +7,9 @@ rust_helper_krealloc(const void *objp, size_t new_size, gfp_t flags) { return krealloc(objp, new_size, flags); } + +void * __must_check __realloc_size(2) +rust_helper_kvrealloc(const void *p, size_t size, gfp_t flags) +{ + return kvrealloc(p, size, flags); +} diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs index ee4c828cbd58..f8a1f0feb25d 100644 --- a/rust/kernel/alloc/allocator.rs +++ b/rust/kernel/alloc/allocator.rs @@ -34,6 +34,15 @@ pub struct Kmalloc; /// For more details see [self]. pub struct Vmalloc; +/// The kvmalloc kernel allocator. +/// +/// `KVmalloc` attempts to allocate memory with `Kmalloc` first, but falls back to `Vmalloc` upon +/// failure. This allocator is typically used when the size for the requested allocation is not +/// known and may exceed the capabilities of `Kmalloc`. +/// +/// For more details see [self]. +pub struct KVmalloc; + /// Returns a proper size to alloc a new object aligned to `new_layout`'s alignment. fn aligned_size(new_layout: Layout) -> usize { // Customized layouts from `Layout::from_size_align()` can have size < align, so pad first. @@ -76,6 +85,9 @@ impl ReallocFunc { // INVARIANT: `vrealloc` satisfies the type invariants. const VREALLOC: Self = Self(bindings::vrealloc); + // INVARIANT: `kvrealloc` satisfies the type invariants. + const KVREALLOC: Self = Self(bindings::kvrealloc); + /// # Safety /// /// This method has the same safety requirements as [`Allocator::realloc`]. @@ -205,6 +217,30 @@ unsafe impl Allocator for Vmalloc { } } +// SAFETY: `realloc` delegates to `ReallocFunc::call`, which guarantees that +// - memory remains valid until it is explicitly freed, +// - passing a pointer to a valid memory allocation is OK, +// - `realloc` satisfies the guarantees, since `ReallocFunc::call` has the same. +unsafe impl Allocator for KVmalloc { + #[inline] + unsafe fn realloc( + ptr: Option>, + layout: Layout, + old_layout: Layout, + flags: Flags, + ) -> Result, AllocError> { + // TODO: Support alignments larger than PAGE_SIZE. + if layout.align() > bindings::PAGE_SIZE { + pr_warn!("KVmalloc does not support alignments larger than PAGE_SIZE yet.\n"); + return Err(AllocError); + } + + // SAFETY: If not `None`, `ptr` is guaranteed to point to valid memory, which was previously + // allocated with this `Allocator`. + unsafe { ReallocFunc::KVREALLOC.call(ptr, layout, old_layout, flags) } + } +} + #[global_allocator] static ALLOCATOR: Kmalloc = Kmalloc; diff --git a/rust/kernel/alloc/allocator_test.rs b/rust/kernel/alloc/allocator_test.rs index 32a1450c4d39..bd0cbcd93e52 100644 --- a/rust/kernel/alloc/allocator_test.rs +++ b/rust/kernel/alloc/allocator_test.rs @@ -8,6 +8,7 @@ use core::ptr::NonNull; pub struct Kmalloc; pub type Vmalloc = Kmalloc; +pub type KVmalloc = Kmalloc; unsafe impl Allocator for Kmalloc { unsafe fn realloc( -- cgit v1.2.3 From 392e34b6bc22077ef63abf62387ea3e9f39418c1 Mon Sep 17 00:00:00 2001 From: Danilo Krummrich Date: Fri, 4 Oct 2024 17:41:32 +0200 Subject: kbuild: rust: remove the `alloc` crate and `GlobalAlloc` Now that we have our own `Allocator`, `Box` and `Vec` types we can remove Rust's `alloc` crate and the `new_uninit` unstable feature. Also remove `Kmalloc`'s `GlobalAlloc` implementation -- we can't remove this in a separate patch, since the `alloc` crate requires a `#[global_allocator]` to set, that implements `GlobalAlloc`. Signed-off-by: Danilo Krummrich Link: https://lore.kernel.org/r/20241004154149.93856-29-dakr@kernel.org Signed-off-by: Miguel Ojeda --- rust/Makefile | 43 ++++++-------------------- rust/exports.c | 1 - rust/kernel/alloc/allocator.rs | 65 ++------------------------------------- scripts/Makefile.build | 4 +-- scripts/generate_rust_analyzer.py | 11 ++----- 5 files changed, 16 insertions(+), 108 deletions(-) (limited to 'rust/kernel/alloc/allocator.rs') diff --git a/rust/Makefile b/rust/Makefile index 0856fd6bc610..3678e79317f1 100644 --- a/rust/Makefile +++ b/rust/Makefile @@ -15,8 +15,8 @@ always-$(CONFIG_RUST) += libmacros.so no-clean-files += libmacros.so always-$(CONFIG_RUST) += bindings/bindings_generated.rs bindings/bindings_helpers_generated.rs -obj-$(CONFIG_RUST) += alloc.o bindings.o kernel.o -always-$(CONFIG_RUST) += exports_alloc_generated.h exports_helpers_generated.h \ +obj-$(CONFIG_RUST) += bindings.o kernel.o +always-$(CONFIG_RUST) += exports_helpers_generated.h \ exports_bindings_generated.h exports_kernel_generated.h always-$(CONFIG_RUST) += uapi/uapi_generated.rs @@ -53,11 +53,6 @@ endif core-cfgs = \ --cfg no_fp_fmt_parse -alloc-cfgs = \ - --cfg no_global_oom_handling \ - --cfg no_rc \ - --cfg no_sync - quiet_cmd_rustdoc = RUSTDOC $(if $(rustdoc_host),H, ) $< cmd_rustdoc = \ OBJTREE=$(abspath $(objtree)) \ @@ -81,7 +76,7 @@ quiet_cmd_rustdoc = RUSTDOC $(if $(rustdoc_host),H, ) $< # command-like flags to solve the issue. Meanwhile, we use the non-custom case # and then retouch the generated files. rustdoc: rustdoc-core rustdoc-macros rustdoc-compiler_builtins \ - rustdoc-alloc rustdoc-kernel + rustdoc-kernel $(Q)cp $(srctree)/Documentation/images/logo.svg $(rustdoc_output)/static.files/ $(Q)cp $(srctree)/Documentation/images/COPYING-logo $(rustdoc_output)/static.files/ $(Q)find $(rustdoc_output) -name '*.html' -type f -print0 | xargs -0 sed -Ei \ @@ -108,20 +103,11 @@ rustdoc-core: $(RUST_LIB_SRC)/core/src/lib.rs FORCE rustdoc-compiler_builtins: $(src)/compiler_builtins.rs rustdoc-core FORCE +$(call if_changed,rustdoc) -# We need to allow `rustdoc::broken_intra_doc_links` because some -# `no_global_oom_handling` functions refer to non-`no_global_oom_handling` -# functions. Ideally `rustdoc` would have a way to distinguish broken links -# due to things that are "configured out" vs. entirely non-existing ones. -rustdoc-alloc: private rustc_target_flags = $(alloc-cfgs) \ - -Arustdoc::broken_intra_doc_links -rustdoc-alloc: $(RUST_LIB_SRC)/alloc/src/lib.rs rustdoc-core rustdoc-compiler_builtins FORCE - +$(call if_changed,rustdoc) - -rustdoc-kernel: private rustc_target_flags = --extern alloc \ +rustdoc-kernel: private rustc_target_flags = \ --extern build_error --extern macros=$(objtree)/$(obj)/libmacros.so \ --extern bindings --extern uapi rustdoc-kernel: $(src)/kernel/lib.rs rustdoc-core rustdoc-macros \ - rustdoc-compiler_builtins rustdoc-alloc $(obj)/libmacros.so \ + rustdoc-compiler_builtins $(obj)/libmacros.so \ $(obj)/bindings.o FORCE +$(call if_changed,rustdoc) @@ -165,7 +151,7 @@ quiet_cmd_rustdoc_test_kernel = RUSTDOC TK $< mkdir -p $(objtree)/$(obj)/test/doctests/kernel; \ OBJTREE=$(abspath $(objtree)) \ $(RUSTDOC) --test $(rust_flags) \ - -L$(objtree)/$(obj) --extern alloc --extern kernel \ + -L$(objtree)/$(obj) --extern kernel \ --extern build_error --extern macros \ --extern bindings --extern uapi \ --no-run --crate-name kernel -Zunstable-options \ @@ -201,7 +187,7 @@ rusttest-macros: $(src)/macros/lib.rs FORCE +$(call if_changed,rustc_test) +$(call if_changed,rustdoc_test) -rusttest-kernel: private rustc_target_flags = --extern alloc \ +rusttest-kernel: private rustc_target_flags = \ --extern build_error --extern macros --extern bindings --extern uapi rusttest-kernel: $(src)/kernel/lib.rs \ rusttestlib-build_error rusttestlib-macros rusttestlib-bindings \ @@ -314,9 +300,6 @@ quiet_cmd_exports = EXPORTS $@ $(obj)/exports_core_generated.h: $(obj)/core.o FORCE $(call if_changed,exports) -$(obj)/exports_alloc_generated.h: $(obj)/alloc.o FORCE - $(call if_changed,exports) - # Even though Rust kernel modules should never use the bindings directly, # symbols from the `bindings` crate and the C helpers need to be exported # because Rust generics and inlined functions may not get their code generated @@ -363,7 +346,7 @@ quiet_cmd_rustc_library = $(if $(skip_clippy),RUSTC,$(RUSTC_OR_CLIPPY_QUIET)) L rust-analyzer: $(Q)$(srctree)/scripts/generate_rust_analyzer.py \ - --cfgs='core=$(core-cfgs)' --cfgs='alloc=$(alloc-cfgs)' \ + --cfgs='core=$(core-cfgs)' \ $(realpath $(srctree)) $(realpath $(objtree)) \ $(rustc_sysroot) $(RUST_LIB_SRC) $(KBUILD_EXTMOD) > \ $(if $(KBUILD_EXTMOD),$(extmod_prefix),$(objtree))/rust-project.json @@ -401,12 +384,6 @@ $(obj)/compiler_builtins.o: private rustc_objcopy = -w -W '__*' $(obj)/compiler_builtins.o: $(src)/compiler_builtins.rs $(obj)/core.o FORCE +$(call if_changed_rule,rustc_library) -$(obj)/alloc.o: private skip_clippy = 1 -$(obj)/alloc.o: private skip_flags = -Wunreachable_pub -$(obj)/alloc.o: private rustc_target_flags = $(alloc-cfgs) -$(obj)/alloc.o: $(RUST_LIB_SRC)/alloc/src/lib.rs $(obj)/compiler_builtins.o FORCE - +$(call if_changed_rule,rustc_library) - $(obj)/build_error.o: $(src)/build_error.rs $(obj)/compiler_builtins.o FORCE +$(call if_changed_rule,rustc_library) @@ -421,9 +398,9 @@ $(obj)/uapi.o: $(src)/uapi/lib.rs \ $(obj)/uapi/uapi_generated.rs FORCE +$(call if_changed_rule,rustc_library) -$(obj)/kernel.o: private rustc_target_flags = --extern alloc \ +$(obj)/kernel.o: private rustc_target_flags = \ --extern build_error --extern macros --extern bindings --extern uapi -$(obj)/kernel.o: $(src)/kernel/lib.rs $(obj)/alloc.o $(obj)/build_error.o \ +$(obj)/kernel.o: $(src)/kernel/lib.rs $(obj)/build_error.o \ $(obj)/libmacros.so $(obj)/bindings.o $(obj)/uapi.o FORCE +$(call if_changed_rule,rustc_library) diff --git a/rust/exports.c b/rust/exports.c index e5695f3b45b7..82a037381798 100644 --- a/rust/exports.c +++ b/rust/exports.c @@ -16,7 +16,6 @@ #define EXPORT_SYMBOL_RUST_GPL(sym) extern int sym; EXPORT_SYMBOL_GPL(sym) #include "exports_core_generated.h" -#include "exports_alloc_generated.h" #include "exports_helpers_generated.h" #include "exports_bindings_generated.h" #include "exports_kernel_generated.h" diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs index f8a1f0feb25d..a041bbfdabec 100644 --- a/rust/kernel/alloc/allocator.rs +++ b/rust/kernel/alloc/allocator.rs @@ -8,8 +8,8 @@ //! //! Reference: -use super::{flags::*, Flags}; -use core::alloc::{GlobalAlloc, Layout}; +use super::Flags; +use core::alloc::Layout; use core::ptr; use core::ptr::NonNull; @@ -54,23 +54,6 @@ fn aligned_size(new_layout: Layout) -> usize { layout.size() } -/// Calls `krealloc` with a proper size to alloc a new object aligned to `new_layout`'s alignment. -/// -/// # Safety -/// -/// - `ptr` can be either null or a pointer which has been allocated by this allocator. -/// - `new_layout` must have a non-zero size. -pub(crate) unsafe fn krealloc_aligned(ptr: *mut u8, new_layout: Layout, flags: Flags) -> *mut u8 { - let size = aligned_size(new_layout); - - // SAFETY: - // - `ptr` is either null or a pointer returned from a previous `k{re}alloc()` by the - // function safety requirement. - // - `size` is greater than 0 since it's from `layout.size()` (which cannot be zero according - // to the function safety requirement) - unsafe { bindings::krealloc(ptr as *const core::ffi::c_void, size, flags.0) as *mut u8 } -} - /// # Invariants /// /// One of the following: `krealloc`, `vrealloc`, `kvrealloc`. @@ -156,43 +139,6 @@ unsafe impl Allocator for Kmalloc { } } -// SAFETY: TODO. -unsafe impl GlobalAlloc for Kmalloc { - unsafe fn alloc(&self, layout: Layout) -> *mut u8 { - // SAFETY: `ptr::null_mut()` is null and `layout` has a non-zero size by the function safety - // requirement. - unsafe { krealloc_aligned(ptr::null_mut(), layout, GFP_KERNEL) } - } - - unsafe fn dealloc(&self, ptr: *mut u8, _layout: Layout) { - // SAFETY: TODO. - unsafe { - bindings::kfree(ptr as *const core::ffi::c_void); - } - } - - unsafe fn realloc(&self, ptr: *mut u8, layout: Layout, new_size: usize) -> *mut u8 { - // SAFETY: - // - `new_size`, when rounded up to the nearest multiple of `layout.align()`, will not - // overflow `isize` by the function safety requirement. - // - `layout.align()` is a proper alignment (i.e. not zero and must be a power of two). - let layout = unsafe { Layout::from_size_align_unchecked(new_size, layout.align()) }; - - // SAFETY: - // - `ptr` is either null or a pointer allocated by this allocator by the function safety - // requirement. - // - the size of `layout` is not zero because `new_size` is not zero by the function safety - // requirement. - unsafe { krealloc_aligned(ptr, layout, GFP_KERNEL) } - } - - unsafe fn alloc_zeroed(&self, layout: Layout) -> *mut u8 { - // SAFETY: `ptr::null_mut()` is null and `layout` has a non-zero size by the function safety - // requirement. - unsafe { krealloc_aligned(ptr::null_mut(), layout, GFP_KERNEL | __GFP_ZERO) } - } -} - // SAFETY: `realloc` delegates to `ReallocFunc::call`, which guarantees that // - memory remains valid until it is explicitly freed, // - passing a pointer to a valid memory allocation is OK, @@ -240,10 +186,3 @@ unsafe impl Allocator for KVmalloc { unsafe { ReallocFunc::KVREALLOC.call(ptr, layout, old_layout, flags) } } } - -#[global_allocator] -static ALLOCATOR: Kmalloc = Kmalloc; - -// See . -#[no_mangle] -static __rust_no_alloc_shim_is_unstable: u8 = 0; diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 64518c2f3d9c..2bba59e790b8 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -248,7 +248,7 @@ $(obj)/%.lst: $(obj)/%.c FORCE # Compile Rust sources (.rs) # --------------------------------------------------------------------------- -rust_allowed_features := arbitrary_self_types,lint_reasons,new_uninit +rust_allowed_features := arbitrary_self_types,lint_reasons # `--out-dir` is required to avoid temporaries being created by `rustc` in the # current working directory, which may be not accessible in the out-of-tree @@ -258,7 +258,7 @@ rust_common_cmd = \ -Zallow-features=$(rust_allowed_features) \ -Zcrate-attr=no_std \ -Zcrate-attr='feature($(rust_allowed_features))' \ - -Zunstable-options --extern force:alloc --extern kernel \ + -Zunstable-options --extern kernel \ --crate-type rlib -L $(objtree)/rust/ \ --crate-name $(basename $(notdir $@)) \ --sysroot=/dev/null \ diff --git a/scripts/generate_rust_analyzer.py b/scripts/generate_rust_analyzer.py index d2bc63cde8c6..09e1d166d8d2 100755 --- a/scripts/generate_rust_analyzer.py +++ b/scripts/generate_rust_analyzer.py @@ -64,13 +64,6 @@ def generate_crates(srctree, objtree, sysroot_src, external_src, cfgs): [], ) - append_crate( - "alloc", - sysroot_src / "alloc" / "src" / "lib.rs", - ["core", "compiler_builtins"], - cfg=crates_cfgs.get("alloc", []), - ) - append_crate( "macros", srctree / "rust" / "macros" / "lib.rs", @@ -96,7 +89,7 @@ def generate_crates(srctree, objtree, sysroot_src, external_src, cfgs): append_crate( "kernel", srctree / "rust" / "kernel" / "lib.rs", - ["core", "alloc", "macros", "build_error", "bindings"], + ["core", "macros", "build_error", "bindings"], cfg=cfg, ) crates[-1]["source"] = { @@ -133,7 +126,7 @@ def generate_crates(srctree, objtree, sysroot_src, external_src, cfgs): append_crate( name, path, - ["core", "alloc", "kernel"], + ["core", "kernel"], cfg=cfg, ) -- cgit v1.2.3 From d072acda4862f095ec9056979b654cc06a22cc68 Mon Sep 17 00:00:00 2001 From: Gary Guo Date: Fri, 13 Sep 2024 22:29:23 +0100 Subject: rust: use custom FFI integer types Currently FFI integer types are defined in libcore. This commit creates the `ffi` crate and asks bindgen to use that crate for FFI integer types instead of `core::ffi`. This commit is preparatory and no type changes are made in this commit yet. Signed-off-by: Gary Guo Link: https://lore.kernel.org/r/20240913213041.395655-4-gary@garyguo.net [ Added `rustdoc`, `rusttest` and KUnit tests support. Rebased on top of `rust-next` (e.g. migrated more `core::ffi` cases). Reworded crate docs slightly and formatted. - Miguel ] Signed-off-by: Miguel Ojeda --- rust/Makefile | 39 ++++++++++++++++++++++++------------- rust/ffi.rs | 13 +++++++++++++ rust/kernel/alloc/allocator.rs | 2 +- rust/kernel/alloc/allocator_test.rs | 4 ++-- rust/kernel/alloc/kbox.rs | 12 ++++++------ rust/kernel/block/mq/operations.rs | 18 ++++++++--------- rust/kernel/block/mq/raw_writer.rs | 2 +- rust/kernel/block/mq/tag_set.rs | 2 +- rust/kernel/error.rs | 20 +++++++++---------- rust/kernel/init.rs | 2 +- rust/kernel/lib.rs | 2 ++ rust/kernel/net/phy.rs | 16 +++++++-------- rust/kernel/str.rs | 4 ++-- rust/kernel/sync/arc.rs | 6 +++--- rust/kernel/sync/condvar.rs | 2 +- rust/kernel/sync/lock.rs | 2 +- rust/kernel/sync/lock/mutex.rs | 2 +- rust/kernel/sync/lock/spinlock.rs | 2 +- rust/kernel/task.rs | 8 ++------ rust/kernel/time.rs | 4 ++-- rust/kernel/types.rs | 14 ++++++------- rust/kernel/uaccess.rs | 6 +++--- rust/macros/module.rs | 8 ++++---- 23 files changed, 107 insertions(+), 83 deletions(-) create mode 100644 rust/ffi.rs (limited to 'rust/kernel/alloc/allocator.rs') diff --git a/rust/Makefile b/rust/Makefile index fcec0e1d9762..f349e7b067ea 100644 --- a/rust/Makefile +++ b/rust/Makefile @@ -3,7 +3,7 @@ # Where to place rustdoc generated documentation rustdoc_output := $(objtree)/Documentation/output/rust/rustdoc -obj-$(CONFIG_RUST) += core.o compiler_builtins.o +obj-$(CONFIG_RUST) += core.o compiler_builtins.o ffi.o always-$(CONFIG_RUST) += exports_core_generated.h # Missing prototypes are expected in the helpers since these are exported @@ -103,10 +103,13 @@ rustdoc-core: $(RUST_LIB_SRC)/core/src/lib.rs FORCE rustdoc-compiler_builtins: $(src)/compiler_builtins.rs rustdoc-core FORCE +$(call if_changed,rustdoc) -rustdoc-kernel: private rustc_target_flags = \ +rustdoc-ffi: $(src)/ffi.rs rustdoc-core FORCE + +$(call if_changed,rustdoc) + +rustdoc-kernel: private rustc_target_flags = --extern ffi \ --extern build_error --extern macros=$(objtree)/$(obj)/libmacros.so \ --extern bindings --extern uapi -rustdoc-kernel: $(src)/kernel/lib.rs rustdoc-core rustdoc-macros \ +rustdoc-kernel: $(src)/kernel/lib.rs rustdoc-core rustdoc-ffi rustdoc-macros \ rustdoc-compiler_builtins $(obj)/libmacros.so \ $(obj)/bindings.o FORCE +$(call if_changed,rustdoc) @@ -124,12 +127,15 @@ quiet_cmd_rustc_test_library = RUSTC TL $< rusttestlib-build_error: $(src)/build_error.rs FORCE +$(call if_changed,rustc_test_library) +rusttestlib-ffi: $(src)/ffi.rs FORCE + +$(call if_changed,rustc_test_library) + rusttestlib-macros: private rustc_target_flags = --extern proc_macro rusttestlib-macros: private rustc_test_library_proc = yes rusttestlib-macros: $(src)/macros/lib.rs FORCE +$(call if_changed,rustc_test_library) -rusttestlib-kernel: private rustc_target_flags = \ +rusttestlib-kernel: private rustc_target_flags = --extern ffi \ --extern build_error --extern macros \ --extern bindings --extern uapi rusttestlib-kernel: $(src)/kernel/lib.rs \ @@ -137,10 +143,12 @@ rusttestlib-kernel: $(src)/kernel/lib.rs \ $(obj)/libmacros.so $(obj)/bindings.o FORCE +$(call if_changed,rustc_test_library) -rusttestlib-bindings: $(src)/bindings/lib.rs FORCE +rusttestlib-bindings: private rustc_target_flags = --extern ffi +rusttestlib-bindings: $(src)/bindings/lib.rs rusttestlib-ffi FORCE +$(call if_changed,rustc_test_library) -rusttestlib-uapi: $(src)/uapi/lib.rs FORCE +rusttestlib-uapi: private rustc_target_flags = --extern ffi +rusttestlib-uapi: $(src)/uapi/lib.rs rusttestlib-ffi FORCE +$(call if_changed,rustc_test_library) quiet_cmd_rustdoc_test = RUSTDOC T $< @@ -160,7 +168,7 @@ quiet_cmd_rustdoc_test_kernel = RUSTDOC TK $< mkdir -p $(objtree)/$(obj)/test/doctests/kernel; \ OBJTREE=$(abspath $(objtree)) \ $(RUSTDOC) --test $(rust_flags) \ - -L$(objtree)/$(obj) --extern kernel \ + -L$(objtree)/$(obj) --extern ffi --extern kernel \ --extern build_error --extern macros \ --extern bindings --extern uapi \ --no-run --crate-name kernel -Zunstable-options \ @@ -198,9 +206,9 @@ rusttest-macros: $(src)/macros/lib.rs \ +$(call if_changed,rustc_test) +$(call if_changed,rustdoc_test) -rusttest-kernel: private rustc_target_flags = \ +rusttest-kernel: private rustc_target_flags = --extern ffi \ --extern build_error --extern macros --extern bindings --extern uapi -rusttest-kernel: $(src)/kernel/lib.rs rusttestlib-kernel \ +rusttest-kernel: $(src)/kernel/lib.rs rusttestlib-ffi rusttestlib-kernel \ rusttestlib-build_error rusttestlib-macros rusttestlib-bindings \ rusttestlib-uapi FORCE +$(call if_changed,rustc_test) @@ -273,7 +281,7 @@ bindgen_c_flags_final = $(bindgen_c_flags_lto) -fno-builtin -D__BINDGEN__ quiet_cmd_bindgen = BINDGEN $@ cmd_bindgen = \ $(BINDGEN) $< $(bindgen_target_flags) \ - --use-core --with-derive-default --ctypes-prefix core::ffi --no-layout-tests \ + --use-core --with-derive-default --ctypes-prefix ffi --no-layout-tests \ --no-debug '.*' --enable-function-attribute-detection \ -o $@ -- $(bindgen_c_flags_final) -DMODULE \ $(bindgen_target_cflags) $(bindgen_target_extra) @@ -401,18 +409,23 @@ $(obj)/compiler_builtins.o: $(src)/compiler_builtins.rs $(obj)/core.o FORCE $(obj)/build_error.o: $(src)/build_error.rs $(obj)/compiler_builtins.o FORCE +$(call if_changed_rule,rustc_library) +$(obj)/ffi.o: $(src)/ffi.rs $(obj)/compiler_builtins.o FORCE + +$(call if_changed_rule,rustc_library) + +$(obj)/bindings.o: private rustc_target_flags = --extern ffi $(obj)/bindings.o: $(src)/bindings/lib.rs \ - $(obj)/compiler_builtins.o \ + $(obj)/ffi.o \ $(obj)/bindings/bindings_generated.rs \ $(obj)/bindings/bindings_helpers_generated.rs FORCE +$(call if_changed_rule,rustc_library) +$(obj)/uapi.o: private rustc_target_flags = --extern ffi $(obj)/uapi.o: $(src)/uapi/lib.rs \ - $(obj)/compiler_builtins.o \ + $(obj)/ffi.o \ $(obj)/uapi/uapi_generated.rs FORCE +$(call if_changed_rule,rustc_library) -$(obj)/kernel.o: private rustc_target_flags = \ +$(obj)/kernel.o: private rustc_target_flags = --extern ffi \ --extern build_error --extern macros --extern bindings --extern uapi $(obj)/kernel.o: $(src)/kernel/lib.rs $(obj)/build_error.o \ $(obj)/libmacros.so $(obj)/bindings.o $(obj)/uapi.o FORCE diff --git a/rust/ffi.rs b/rust/ffi.rs new file mode 100644 index 000000000000..be153c4d551b --- /dev/null +++ b/rust/ffi.rs @@ -0,0 +1,13 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! Foreign function interface (FFI) types. +//! +//! This crate provides mapping from C primitive types to Rust ones. +//! +//! The Rust [`core`] crate provides [`core::ffi`], which maps integer types to the platform default +//! C ABI. The kernel does not use [`core::ffi`], so it can customise the mapping that deviates from +//! the platform default. + +#![no_std] + +pub use core::ffi::*; diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs index a041bbfdabec..439985e29fbc 100644 --- a/rust/kernel/alloc/allocator.rs +++ b/rust/kernel/alloc/allocator.rs @@ -58,7 +58,7 @@ fn aligned_size(new_layout: Layout) -> usize { /// /// One of the following: `krealloc`, `vrealloc`, `kvrealloc`. struct ReallocFunc( - unsafe extern "C" fn(*const core::ffi::c_void, usize, u32) -> *mut core::ffi::c_void, + unsafe extern "C" fn(*const crate::ffi::c_void, usize, u32) -> *mut crate::ffi::c_void, ); impl ReallocFunc { diff --git a/rust/kernel/alloc/allocator_test.rs b/rust/kernel/alloc/allocator_test.rs index 54ca85964d4a..e3240d16040b 100644 --- a/rust/kernel/alloc/allocator_test.rs +++ b/rust/kernel/alloc/allocator_test.rs @@ -24,10 +24,10 @@ pub type KVmalloc = Kmalloc; extern "C" { #[link_name = "aligned_alloc"] - fn libc_aligned_alloc(align: usize, size: usize) -> *mut core::ffi::c_void; + fn libc_aligned_alloc(align: usize, size: usize) -> *mut crate::ffi::c_void; #[link_name = "free"] - fn libc_free(ptr: *mut core::ffi::c_void); + fn libc_free(ptr: *mut crate::ffi::c_void); } // SAFETY: diff --git a/rust/kernel/alloc/kbox.rs b/rust/kernel/alloc/kbox.rs index d69c32496b86..9ce414361c2c 100644 --- a/rust/kernel/alloc/kbox.rs +++ b/rust/kernel/alloc/kbox.rs @@ -355,17 +355,17 @@ where { type Borrowed<'a> = &'a T; - fn into_foreign(self) -> *const core::ffi::c_void { + fn into_foreign(self) -> *const crate::ffi::c_void { Box::into_raw(self) as _ } - unsafe fn from_foreign(ptr: *const core::ffi::c_void) -> Self { + unsafe fn from_foreign(ptr: *const crate::ffi::c_void) -> Self { // SAFETY: The safety requirements of this function ensure that `ptr` comes from a previous // call to `Self::into_foreign`. unsafe { Box::from_raw(ptr as _) } } - unsafe fn borrow<'a>(ptr: *const core::ffi::c_void) -> &'a T { + unsafe fn borrow<'a>(ptr: *const crate::ffi::c_void) -> &'a T { // SAFETY: The safety requirements of this method ensure that the object remains alive and // immutable for the duration of 'a. unsafe { &*ptr.cast() } @@ -378,18 +378,18 @@ where { type Borrowed<'a> = Pin<&'a T>; - fn into_foreign(self) -> *const core::ffi::c_void { + fn into_foreign(self) -> *const crate::ffi::c_void { // SAFETY: We are still treating the box as pinned. Box::into_raw(unsafe { Pin::into_inner_unchecked(self) }) as _ } - unsafe fn from_foreign(ptr: *const core::ffi::c_void) -> Self { + unsafe fn from_foreign(ptr: *const crate::ffi::c_void) -> Self { // SAFETY: The safety requirements of this function ensure that `ptr` comes from a previous // call to `Self::into_foreign`. unsafe { Pin::new_unchecked(Box::from_raw(ptr as _)) } } - unsafe fn borrow<'a>(ptr: *const core::ffi::c_void) -> Pin<&'a T> { + unsafe fn borrow<'a>(ptr: *const crate::ffi::c_void) -> Pin<&'a T> { // SAFETY: The safety requirements for this function ensure that the object is still alive, // so it is safe to dereference the raw pointer. // The safety requirements of `from_foreign` also ensure that the object remains alive for diff --git a/rust/kernel/block/mq/operations.rs b/rust/kernel/block/mq/operations.rs index 9ba7fdfeb4b2..c8646d0d9866 100644 --- a/rust/kernel/block/mq/operations.rs +++ b/rust/kernel/block/mq/operations.rs @@ -131,7 +131,7 @@ impl OperationsVTable { unsafe extern "C" fn poll_callback( _hctx: *mut bindings::blk_mq_hw_ctx, _iob: *mut bindings::io_comp_batch, - ) -> core::ffi::c_int { + ) -> crate::ffi::c_int { T::poll().into() } @@ -145,9 +145,9 @@ impl OperationsVTable { /// for the same context. unsafe extern "C" fn init_hctx_callback( _hctx: *mut bindings::blk_mq_hw_ctx, - _tagset_data: *mut core::ffi::c_void, - _hctx_idx: core::ffi::c_uint, - ) -> core::ffi::c_int { + _tagset_data: *mut crate::ffi::c_void, + _hctx_idx: crate::ffi::c_uint, + ) -> crate::ffi::c_int { from_result(|| Ok(0)) } @@ -159,7 +159,7 @@ impl OperationsVTable { /// This function may only be called by blk-mq C infrastructure. unsafe extern "C" fn exit_hctx_callback( _hctx: *mut bindings::blk_mq_hw_ctx, - _hctx_idx: core::ffi::c_uint, + _hctx_idx: crate::ffi::c_uint, ) { } @@ -176,9 +176,9 @@ impl OperationsVTable { unsafe extern "C" fn init_request_callback( _set: *mut bindings::blk_mq_tag_set, rq: *mut bindings::request, - _hctx_idx: core::ffi::c_uint, - _numa_node: core::ffi::c_uint, - ) -> core::ffi::c_int { + _hctx_idx: crate::ffi::c_uint, + _numa_node: crate::ffi::c_uint, + ) -> crate::ffi::c_int { from_result(|| { // SAFETY: By the safety requirements of this function, `rq` points // to a valid allocation. @@ -203,7 +203,7 @@ impl OperationsVTable { unsafe extern "C" fn exit_request_callback( _set: *mut bindings::blk_mq_tag_set, rq: *mut bindings::request, - _hctx_idx: core::ffi::c_uint, + _hctx_idx: crate::ffi::c_uint, ) { // SAFETY: The tagset invariants guarantee that all requests are allocated with extra memory // for the request data. diff --git a/rust/kernel/block/mq/raw_writer.rs b/rust/kernel/block/mq/raw_writer.rs index 9222465d670b..7e2159e4f6a6 100644 --- a/rust/kernel/block/mq/raw_writer.rs +++ b/rust/kernel/block/mq/raw_writer.rs @@ -25,7 +25,7 @@ impl<'a> RawWriter<'a> { } pub(crate) fn from_array( - a: &'a mut [core::ffi::c_char; N], + a: &'a mut [crate::ffi::c_char; N], ) -> Result> { Self::new( // SAFETY: the buffer of `a` is valid for read and write as `u8` for diff --git a/rust/kernel/block/mq/tag_set.rs b/rust/kernel/block/mq/tag_set.rs index f9a1ca655a35..d7f175a05d99 100644 --- a/rust/kernel/block/mq/tag_set.rs +++ b/rust/kernel/block/mq/tag_set.rs @@ -53,7 +53,7 @@ impl TagSet { queue_depth: num_tags, cmd_size, flags: bindings::BLK_MQ_F_SHOULD_MERGE, - driver_data: core::ptr::null_mut::(), + driver_data: core::ptr::null_mut::(), nr_maps: num_maps, ..tag_set } diff --git a/rust/kernel/error.rs b/rust/kernel/error.rs index 7cd3bbab52f2..52c502432447 100644 --- a/rust/kernel/error.rs +++ b/rust/kernel/error.rs @@ -100,7 +100,7 @@ impl Error { /// /// It is a bug to pass an out-of-range `errno`. `EINVAL` would /// be returned in such a case. - pub fn from_errno(errno: core::ffi::c_int) -> Error { + pub fn from_errno(errno: crate::ffi::c_int) -> Error { if errno < -(bindings::MAX_ERRNO as i32) || errno >= 0 { // TODO: Make it a `WARN_ONCE` once available. crate::pr_warn!( @@ -119,7 +119,7 @@ impl Error { /// Creates an [`Error`] from a kernel error code. /// /// Returns [`None`] if `errno` is out-of-range. - const fn try_from_errno(errno: core::ffi::c_int) -> Option { + const fn try_from_errno(errno: crate::ffi::c_int) -> Option { if errno < -(bindings::MAX_ERRNO as i32) || errno >= 0 { return None; } @@ -133,7 +133,7 @@ impl Error { /// # Safety /// /// `errno` must be within error code range (i.e. `>= -MAX_ERRNO && < 0`). - const unsafe fn from_errno_unchecked(errno: core::ffi::c_int) -> Error { + const unsafe fn from_errno_unchecked(errno: crate::ffi::c_int) -> Error { // INVARIANT: The contract ensures the type invariant // will hold. // SAFETY: The caller guarantees `errno` is non-zero. @@ -141,7 +141,7 @@ impl Error { } /// Returns the kernel error code. - pub fn to_errno(self) -> core::ffi::c_int { + pub fn to_errno(self) -> crate::ffi::c_int { self.0.get() } @@ -259,7 +259,7 @@ pub type Result = core::result::Result; /// Converts an integer as returned by a C kernel function to an error if it's negative, and /// `Ok(())` otherwise. -pub fn to_result(err: core::ffi::c_int) -> Result { +pub fn to_result(err: crate::ffi::c_int) -> Result { if err < 0 { Err(Error::from_errno(err)) } else { @@ -282,15 +282,15 @@ pub fn to_result(err: core::ffi::c_int) -> Result { /// fn devm_platform_ioremap_resource( /// pdev: &mut PlatformDevice, /// index: u32, -/// ) -> Result<*mut core::ffi::c_void> { +/// ) -> Result<*mut kernel::ffi::c_void> { /// // SAFETY: `pdev` points to a valid platform device. There are no safety requirements /// // on `index`. /// from_err_ptr(unsafe { bindings::devm_platform_ioremap_resource(pdev.to_ptr(), index) }) /// } /// ``` pub fn from_err_ptr(ptr: *mut T) -> Result<*mut T> { - // CAST: Casting a pointer to `*const core::ffi::c_void` is always valid. - let const_ptr: *const core::ffi::c_void = ptr.cast(); + // CAST: Casting a pointer to `*const crate::ffi::c_void` is always valid. + let const_ptr: *const crate::ffi::c_void = ptr.cast(); // SAFETY: The FFI function does not deref the pointer. if unsafe { bindings::IS_ERR(const_ptr) } { // SAFETY: The FFI function does not deref the pointer. @@ -306,7 +306,7 @@ pub fn from_err_ptr(ptr: *mut T) -> Result<*mut T> { // // SAFETY: `IS_ERR()` ensures `err` is a // negative value greater-or-equal to `-bindings::MAX_ERRNO`. - return Err(unsafe { Error::from_errno_unchecked(err as core::ffi::c_int) }); + return Err(unsafe { Error::from_errno_unchecked(err as crate::ffi::c_int) }); } Ok(ptr) } @@ -326,7 +326,7 @@ pub fn from_err_ptr(ptr: *mut T) -> Result<*mut T> { /// # use kernel::bindings; /// unsafe extern "C" fn probe_callback( /// pdev: *mut bindings::platform_device, -/// ) -> core::ffi::c_int { +/// ) -> kernel::ffi::c_int { /// from_result(|| { /// let ptr = devm_alloc(pdev)?; /// bindings::platform_set_drvdata(pdev, ptr); diff --git a/rust/kernel/init.rs b/rust/kernel/init.rs index c9919ba0b683..347049df556b 100644 --- a/rust/kernel/init.rs +++ b/rust/kernel/init.rs @@ -133,7 +133,7 @@ //! # } //! # // `Error::from_errno` is `pub(crate)` in the `kernel` crate, thus provide a workaround. //! # trait FromErrno { -//! # fn from_errno(errno: core::ffi::c_int) -> Error { +//! # fn from_errno(errno: kernel::ffi::c_int) -> Error { //! # // Dummy error that can be constructed outside the `kernel` crate. //! # Error::from(core::fmt::Error) //! # } diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs index b62451f64f6e..bf8d7f841f94 100644 --- a/rust/kernel/lib.rs +++ b/rust/kernel/lib.rs @@ -27,6 +27,8 @@ compile_error!("Missing kernel configuration for conditional compilation"); // Allow proc-macros to refer to `::kernel` inside the `kernel` crate (this crate). extern crate self as kernel; +pub use ffi; + pub mod alloc; #[cfg(CONFIG_BLOCK)] pub mod block; diff --git a/rust/kernel/net/phy.rs b/rust/kernel/net/phy.rs index 910ce867480a..beb62ec712c3 100644 --- a/rust/kernel/net/phy.rs +++ b/rust/kernel/net/phy.rs @@ -314,7 +314,7 @@ impl Adapter { /// `phydev` must be passed by the corresponding callback in `phy_driver`. unsafe extern "C" fn soft_reset_callback( phydev: *mut bindings::phy_device, - ) -> core::ffi::c_int { + ) -> crate::ffi::c_int { from_result(|| { // SAFETY: This callback is called only in contexts // where we hold `phy_device->lock`, so the accessors on @@ -328,7 +328,7 @@ impl Adapter { /// # Safety /// /// `phydev` must be passed by the corresponding callback in `phy_driver`. - unsafe extern "C" fn probe_callback(phydev: *mut bindings::phy_device) -> core::ffi::c_int { + unsafe extern "C" fn probe_callback(phydev: *mut bindings::phy_device) -> crate::ffi::c_int { from_result(|| { // SAFETY: This callback is called only in contexts // where we can exclusively access `phy_device` because @@ -345,7 +345,7 @@ impl Adapter { /// `phydev` must be passed by the corresponding callback in `phy_driver`. unsafe extern "C" fn get_features_callback( phydev: *mut bindings::phy_device, - ) -> core::ffi::c_int { + ) -> crate::ffi::c_int { from_result(|| { // SAFETY: This callback is called only in contexts // where we hold `phy_device->lock`, so the accessors on @@ -359,7 +359,7 @@ impl Adapter { /// # Safety /// /// `phydev` must be passed by the corresponding callback in `phy_driver`. - unsafe extern "C" fn suspend_callback(phydev: *mut bindings::phy_device) -> core::ffi::c_int { + unsafe extern "C" fn suspend_callback(phydev: *mut bindings::phy_device) -> crate::ffi::c_int { from_result(|| { // SAFETY: The C core code ensures that the accessors on // `Device` are okay to call even though `phy_device->lock` @@ -373,7 +373,7 @@ impl Adapter { /// # Safety /// /// `phydev` must be passed by the corresponding callback in `phy_driver`. - unsafe extern "C" fn resume_callback(phydev: *mut bindings::phy_device) -> core::ffi::c_int { + unsafe extern "C" fn resume_callback(phydev: *mut bindings::phy_device) -> crate::ffi::c_int { from_result(|| { // SAFETY: The C core code ensures that the accessors on // `Device` are okay to call even though `phy_device->lock` @@ -389,7 +389,7 @@ impl Adapter { /// `phydev` must be passed by the corresponding callback in `phy_driver`. unsafe extern "C" fn config_aneg_callback( phydev: *mut bindings::phy_device, - ) -> core::ffi::c_int { + ) -> crate::ffi::c_int { from_result(|| { // SAFETY: This callback is called only in contexts // where we hold `phy_device->lock`, so the accessors on @@ -405,7 +405,7 @@ impl Adapter { /// `phydev` must be passed by the corresponding callback in `phy_driver`. unsafe extern "C" fn read_status_callback( phydev: *mut bindings::phy_device, - ) -> core::ffi::c_int { + ) -> crate::ffi::c_int { from_result(|| { // SAFETY: This callback is called only in contexts // where we hold `phy_device->lock`, so the accessors on @@ -421,7 +421,7 @@ impl Adapter { /// `phydev` must be passed by the corresponding callback in `phy_driver`. unsafe extern "C" fn match_phy_device_callback( phydev: *mut bindings::phy_device, - ) -> core::ffi::c_int { + ) -> crate::ffi::c_int { // SAFETY: This callback is called only in contexts // where we hold `phy_device->lock`, so the accessors on // `Device` are okay to call. diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs index aff6baa521d4..d04c12a1426d 100644 --- a/rust/kernel/str.rs +++ b/rust/kernel/str.rs @@ -184,7 +184,7 @@ impl CStr { /// last at least `'a`. When `CStr` is alive, the memory pointed by `ptr` /// must not be mutated. #[inline] - pub unsafe fn from_char_ptr<'a>(ptr: *const core::ffi::c_char) -> &'a Self { + pub unsafe fn from_char_ptr<'a>(ptr: *const crate::ffi::c_char) -> &'a Self { // SAFETY: The safety precondition guarantees `ptr` is a valid pointer // to a `NUL`-terminated C string. let len = unsafe { bindings::strlen(ptr) } + 1; @@ -247,7 +247,7 @@ impl CStr { /// Returns a C pointer to the string. #[inline] - pub const fn as_char_ptr(&self) -> *const core::ffi::c_char { + pub const fn as_char_ptr(&self) -> *const crate::ffi::c_char { self.0.as_ptr() as _ } diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs index db9da352d588..fa4509406ee9 100644 --- a/rust/kernel/sync/arc.rs +++ b/rust/kernel/sync/arc.rs @@ -332,11 +332,11 @@ impl Arc { impl ForeignOwnable for Arc { type Borrowed<'a> = ArcBorrow<'a, T>; - fn into_foreign(self) -> *const core::ffi::c_void { + fn into_foreign(self) -> *const crate::ffi::c_void { ManuallyDrop::new(self).ptr.as_ptr() as _ } - unsafe fn borrow<'a>(ptr: *const core::ffi::c_void) -> ArcBorrow<'a, T> { + unsafe fn borrow<'a>(ptr: *const crate::ffi::c_void) -> ArcBorrow<'a, T> { // By the safety requirement of this function, we know that `ptr` came from // a previous call to `Arc::into_foreign`. let inner = NonNull::new(ptr as *mut ArcInner).unwrap(); @@ -346,7 +346,7 @@ impl ForeignOwnable for Arc { unsafe { ArcBorrow::new(inner) } } - unsafe fn from_foreign(ptr: *const core::ffi::c_void) -> Self { + unsafe fn from_foreign(ptr: *const crate::ffi::c_void) -> Self { // SAFETY: By the safety requirement of this function, we know that `ptr` came from // a previous call to `Arc::into_foreign`, which guarantees that `ptr` is valid and // holds a reference count increment that is transferrable to us. diff --git a/rust/kernel/sync/condvar.rs b/rust/kernel/sync/condvar.rs index a1a29c0bdb3a..7df565038d7d 100644 --- a/rust/kernel/sync/condvar.rs +++ b/rust/kernel/sync/condvar.rs @@ -7,6 +7,7 @@ use super::{lock::Backend, lock::Guard, LockClassKey}; use crate::{ + ffi::{c_int, c_long}, init::PinInit, pin_init, str::CStr, @@ -14,7 +15,6 @@ use crate::{ time::Jiffies, types::Opaque, }; -use core::ffi::{c_int, c_long}; use core::marker::PhantomPinned; use core::ptr; use macros::pin_data; diff --git a/rust/kernel/sync/lock.rs b/rust/kernel/sync/lock.rs index a5d89cebf106..6d3c8874eb26 100644 --- a/rust/kernel/sync/lock.rs +++ b/rust/kernel/sync/lock.rs @@ -49,7 +49,7 @@ pub unsafe trait Backend { /// remain valid for read indefinitely. unsafe fn init( ptr: *mut Self::State, - name: *const core::ffi::c_char, + name: *const crate::ffi::c_char, key: *mut bindings::lock_class_key, ); diff --git a/rust/kernel/sync/lock/mutex.rs b/rust/kernel/sync/lock/mutex.rs index 9ce43ccb4515..0e946ebefce1 100644 --- a/rust/kernel/sync/lock/mutex.rs +++ b/rust/kernel/sync/lock/mutex.rs @@ -96,7 +96,7 @@ unsafe impl super::Backend for MutexBackend { unsafe fn init( ptr: *mut Self::State, - name: *const core::ffi::c_char, + name: *const crate::ffi::c_char, key: *mut bindings::lock_class_key, ) { // SAFETY: The safety requirements ensure that `ptr` is valid for writes, and `name` and diff --git a/rust/kernel/sync/lock/spinlock.rs b/rust/kernel/sync/lock/spinlock.rs index 040dc16975a6..9f4d128bed98 100644 --- a/rust/kernel/sync/lock/spinlock.rs +++ b/rust/kernel/sync/lock/spinlock.rs @@ -95,7 +95,7 @@ unsafe impl super::Backend for SpinLockBackend { unsafe fn init( ptr: *mut Self::State, - name: *const core::ffi::c_char, + name: *const crate::ffi::c_char, key: *mut bindings::lock_class_key, ) { // SAFETY: The safety requirements ensure that `ptr` is valid for writes, and `name` and diff --git a/rust/kernel/task.rs b/rust/kernel/task.rs index 55dff7e088bf..5bce090a3869 100644 --- a/rust/kernel/task.rs +++ b/rust/kernel/task.rs @@ -4,13 +4,9 @@ //! //! C header: [`include/linux/sched.h`](srctree/include/linux/sched.h). +use crate::ffi::{c_int, c_long, c_uint}; use crate::types::Opaque; -use core::{ - ffi::{c_int, c_long, c_uint}, - marker::PhantomData, - ops::Deref, - ptr, -}; +use core::{marker::PhantomData, ops::Deref, ptr}; /// A sentinel value used for infinite timeouts. pub const MAX_SCHEDULE_TIMEOUT: c_long = c_long::MAX; diff --git a/rust/kernel/time.rs b/rust/kernel/time.rs index e3bb5e89f88d..379c0f5772e5 100644 --- a/rust/kernel/time.rs +++ b/rust/kernel/time.rs @@ -12,10 +12,10 @@ pub const NSEC_PER_MSEC: i64 = bindings::NSEC_PER_MSEC as i64; /// The time unit of Linux kernel. One jiffy equals (1/HZ) second. -pub type Jiffies = core::ffi::c_ulong; +pub type Jiffies = crate::ffi::c_ulong; /// The millisecond time unit. -pub type Msecs = core::ffi::c_uint; +pub type Msecs = crate::ffi::c_uint; /// Converts milliseconds to jiffies. #[inline] diff --git a/rust/kernel/types.rs b/rust/kernel/types.rs index fae80814fa1c..a7eaa29f08a4 100644 --- a/rust/kernel/types.rs +++ b/rust/kernel/types.rs @@ -29,7 +29,7 @@ pub trait ForeignOwnable: Sized { /// For example, it might be invalid, dangling or pointing to uninitialized memory. Using it in /// any way except for [`ForeignOwnable::from_foreign`], [`ForeignOwnable::borrow`], /// [`ForeignOwnable::try_from_foreign`] can result in undefined behavior. - fn into_foreign(self) -> *const core::ffi::c_void; + fn into_foreign(self) -> *const crate::ffi::c_void; /// Borrows a foreign-owned object. /// @@ -37,7 +37,7 @@ pub trait ForeignOwnable: Sized { /// /// `ptr` must have been returned by a previous call to [`ForeignOwnable::into_foreign`] for /// which a previous matching [`ForeignOwnable::from_foreign`] hasn't been called yet. - unsafe fn borrow<'a>(ptr: *const core::ffi::c_void) -> Self::Borrowed<'a>; + unsafe fn borrow<'a>(ptr: *const crate::ffi::c_void) -> Self::Borrowed<'a>; /// Converts a foreign-owned object back to a Rust-owned one. /// @@ -47,7 +47,7 @@ pub trait ForeignOwnable: Sized { /// which a previous matching [`ForeignOwnable::from_foreign`] hasn't been called yet. /// Additionally, all instances (if any) of values returned by [`ForeignOwnable::borrow`] for /// this object must have been dropped. - unsafe fn from_foreign(ptr: *const core::ffi::c_void) -> Self; + unsafe fn from_foreign(ptr: *const crate::ffi::c_void) -> Self; /// Tries to convert a foreign-owned object back to a Rust-owned one. /// @@ -58,7 +58,7 @@ pub trait ForeignOwnable: Sized { /// /// `ptr` must either be null or satisfy the safety requirements for /// [`ForeignOwnable::from_foreign`]. - unsafe fn try_from_foreign(ptr: *const core::ffi::c_void) -> Option { + unsafe fn try_from_foreign(ptr: *const crate::ffi::c_void) -> Option { if ptr.is_null() { None } else { @@ -72,13 +72,13 @@ pub trait ForeignOwnable: Sized { impl ForeignOwnable for () { type Borrowed<'a> = (); - fn into_foreign(self) -> *const core::ffi::c_void { + fn into_foreign(self) -> *const crate::ffi::c_void { core::ptr::NonNull::dangling().as_ptr() } - unsafe fn borrow<'a>(_: *const core::ffi::c_void) -> Self::Borrowed<'a> {} + unsafe fn borrow<'a>(_: *const crate::ffi::c_void) -> Self::Borrowed<'a> {} - unsafe fn from_foreign(_: *const core::ffi::c_void) -> Self {} + unsafe fn from_foreign(_: *const crate::ffi::c_void) -> Self {} } /// Runs a cleanup function/closure when dropped. diff --git a/rust/kernel/uaccess.rs b/rust/kernel/uaccess.rs index 2c953ba53c77..05b0b8d13b10 100644 --- a/rust/kernel/uaccess.rs +++ b/rust/kernel/uaccess.rs @@ -8,10 +8,10 @@ use crate::{ alloc::Flags, bindings, error::Result, + ffi::{c_ulong, c_void}, prelude::*, transmute::{AsBytes, FromBytes}, }; -use core::ffi::{c_ulong, c_void}; use core::mem::{size_of, MaybeUninit}; /// The type used for userspace addresses. @@ -45,7 +45,7 @@ pub type UserPtr = usize; /// every byte in the region. /// /// ```no_run -/// use core::ffi::c_void; +/// use kernel::ffi::c_void; /// use kernel::error::Result; /// use kernel::uaccess::{UserPtr, UserSlice}; /// @@ -67,7 +67,7 @@ pub type UserPtr = usize; /// Example illustrating a TOCTOU (time-of-check to time-of-use) bug. /// /// ```no_run -/// use core::ffi::c_void; +/// use kernel::ffi::c_void; /// use kernel::error::{code::EINVAL, Result}; /// use kernel::uaccess::{UserPtr, UserSlice}; /// diff --git a/rust/macros/module.rs b/rust/macros/module.rs index aef3b132f32b..e7a087b7e884 100644 --- a/rust/macros/module.rs +++ b/rust/macros/module.rs @@ -253,7 +253,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream { #[doc(hidden)] #[no_mangle] #[link_section = \".init.text\"] - pub unsafe extern \"C\" fn init_module() -> core::ffi::c_int {{ + pub unsafe extern \"C\" fn init_module() -> kernel::ffi::c_int {{ // SAFETY: This function is inaccessible to the outside due to the double // module wrapping it. It is called exactly once by the C side via its // unique name. @@ -292,7 +292,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream { #[doc(hidden)] #[link_section = \"{initcall_section}\"] #[used] - pub static __{name}_initcall: extern \"C\" fn() -> core::ffi::c_int = __{name}_init; + pub static __{name}_initcall: extern \"C\" fn() -> kernel::ffi::c_int = __{name}_init; #[cfg(not(MODULE))] #[cfg(CONFIG_HAVE_ARCH_PREL32_RELOCATIONS)] @@ -307,7 +307,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream { #[cfg(not(MODULE))] #[doc(hidden)] #[no_mangle] - pub extern \"C\" fn __{name}_init() -> core::ffi::c_int {{ + pub extern \"C\" fn __{name}_init() -> kernel::ffi::c_int {{ // SAFETY: This function is inaccessible to the outside due to the double // module wrapping it. It is called exactly once by the C side via its // placement above in the initcall section. @@ -330,7 +330,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream { /// # Safety /// /// This function must only be called once. - unsafe fn __init() -> core::ffi::c_int {{ + unsafe fn __init() -> kernel::ffi::c_int {{ match <{type_} as kernel::Module>::init(&super::super::THIS_MODULE) {{ Ok(m) => {{ // SAFETY: No data race, since `__MOD` can only be accessed by this -- cgit v1.2.3