In Rust 1.63.0, Clippy introduced the `as_underscore` lint [1]:
The conversion might include lossy conversion or a dangerous cast that might go undetected due to the type being inferred.
The lint is allowed by default as using `_` is less wordy than always specifying the type.
Always specifying the type is especially helpful in function call contexts where the inferred type may change at a distance. Specifying the type also allows Clippy to spot more cases of `useless_conversion`.
The primary downside is the need to specify the type in trivial getters. There are 4 such functions: 3 have become slightly less ergonomic, 1 was revealed to be a `useless_conversion`.
While this doesn't eliminate unchecked `as` conversions, it makes such conversions easier to scrutinize. It also has the slight benefit of removing a degree of freedom on which to bikeshed. Thus apply the changes and enable the lint -- no functional change intended.
Link: https://rust-lang.github.io/rust-clippy/master/index.html#as_underscore [1] Reviewed-by: Benno Lossin benno.lossin@proton.me Reviewed-by: Boqun Feng boqun.feng@gmail.com Signed-off-by: Tamir Duberstein tamird@gmail.com --- Makefile | 1 + rust/kernel/block/mq/operations.rs | 2 +- rust/kernel/block/mq/request.rs | 7 ++++- rust/kernel/device_id.rs | 2 +- rust/kernel/devres.rs | 13 +++++----- rust/kernel/dma.rs | 2 +- rust/kernel/drm/device.rs | 2 +- rust/kernel/error.rs | 2 +- rust/kernel/io.rs | 18 ++++++------- rust/kernel/miscdevice.rs | 2 +- rust/kernel/mm/virt.rs | 52 +++++++++++++++++++------------------- rust/kernel/of.rs | 6 ++--- rust/kernel/pci.rs | 9 ++++--- rust/kernel/str.rs | 8 +++--- rust/kernel/workqueue.rs | 2 +- 15 files changed, 69 insertions(+), 59 deletions(-)
diff --git a/Makefile b/Makefile index bb33023f87c3..0ba22c361de8 100644 --- a/Makefile +++ b/Makefile @@ -480,6 +480,7 @@ export rust_common_flags := --edition=2021 \ -Wunreachable_pub \ -Wclippy::all \ -Wclippy::as_ptr_cast_mut \ + -Wclippy::as_underscore \ -Wclippy::ignored_unit_patterns \ -Wclippy::mut_mut \ -Wclippy::needless_bitwise_bool \ diff --git a/rust/kernel/block/mq/operations.rs b/rust/kernel/block/mq/operations.rs index 864ff379dc91..c2b98f507bcb 100644 --- a/rust/kernel/block/mq/operations.rs +++ b/rust/kernel/block/mq/operations.rs @@ -101,7 +101,7 @@ impl<T: Operations> OperationsVTable<T> { if let Err(e) = ret { e.to_blk_status() } else { - bindings::BLK_STS_OK as _ + bindings::BLK_STS_OK as bindings::blk_status_t } }
diff --git a/rust/kernel/block/mq/request.rs b/rust/kernel/block/mq/request.rs index af5c9ac94f36..fefd394f064a 100644 --- a/rust/kernel/block/mq/request.rs +++ b/rust/kernel/block/mq/request.rs @@ -125,7 +125,12 @@ pub fn end_ok(this: ARef<Self>) -> Result<(), ARef<Self>> { // success of the call to `try_set_end` guarantees that there are no // `ARef`s pointing to this request. Therefore it is safe to hand it // back to the block layer. - unsafe { bindings::blk_mq_end_request(request_ptr, bindings::BLK_STS_OK as _) }; + unsafe { + bindings::blk_mq_end_request( + request_ptr, + bindings::BLK_STS_OK as bindings::blk_status_t, + ) + };
Ok(()) } diff --git a/rust/kernel/device_id.rs b/rust/kernel/device_id.rs index 0a4eb56d98f2..f9d55ac7b9e6 100644 --- a/rust/kernel/device_id.rs +++ b/rust/kernel/device_id.rs @@ -82,7 +82,7 @@ impl<T: RawDeviceId, U, const N: usize> IdArray<T, U, N> { unsafe { raw_ids[i] .as_mut_ptr() - .byte_offset(T::DRIVER_DATA_OFFSET as _) + .byte_add(T::DRIVER_DATA_OFFSET) .cast::<usize>() .write(i); } diff --git a/rust/kernel/devres.rs b/rust/kernel/devres.rs index 237182446db3..1e44d70687a8 100644 --- a/rust/kernel/devres.rs +++ b/rust/kernel/devres.rs @@ -59,19 +59,19 @@ struct DevresInner<T> { /// unsafe fn new(paddr: usize) -> Result<Self>{ /// // SAFETY: By the safety requirements of this function [`paddr`, `paddr` + `SIZE`) is /// // valid for `ioremap`. -/// let addr = unsafe { bindings::ioremap(paddr as _, SIZE as _) }; +/// let addr = unsafe { bindings::ioremap(paddr as bindings::phys_addr_t, SIZE) }; /// if addr.is_null() { /// return Err(ENOMEM); /// } /// -/// Ok(IoMem(IoRaw::new(addr as _, SIZE)?)) +/// Ok(IoMem(IoRaw::new(addr as usize, SIZE)?)) /// } /// } /// /// impl<const SIZE: usize> Drop for IoMem<SIZE> { /// fn drop(&mut self) { /// // SAFETY: `self.0.addr()` is guaranteed to be properly mapped by `Self::new`. -/// unsafe { bindings::iounmap(self.0.addr() as _); }; +/// unsafe { bindings::iounmap(self.0.addr() as *mut c_void); }; /// } /// } /// @@ -112,8 +112,9 @@ fn new(dev: &Device<Bound>, data: T, flags: Flags) -> Result<Arc<DevresInner<T>>
// SAFETY: `devm_add_action` guarantees to call `Self::devres_callback` once `dev` is // detached. - let ret = - unsafe { bindings::devm_add_action(dev.as_raw(), Some(inner.callback), data as _) }; + let ret = unsafe { + bindings::devm_add_action(dev.as_raw(), Some(inner.callback), data.cast_mut().cast()) + };
if ret != 0 { // SAFETY: We just created another reference to `inner` in order to pass it to @@ -127,7 +128,7 @@ fn new(dev: &Device<Bound>, data: T, flags: Flags) -> Result<Arc<DevresInner<T>> }
fn as_ptr(&self) -> *const Self { - self as _ + self }
fn remove_action(this: &Arc<Self>) { diff --git a/rust/kernel/dma.rs b/rust/kernel/dma.rs index 666bf2d64f9a..8e317005decd 100644 --- a/rust/kernel/dma.rs +++ b/rust/kernel/dma.rs @@ -38,7 +38,7 @@ impl Attrs { /// Get the raw representation of this attribute. pub(crate) fn as_raw(self) -> crate::ffi::c_ulong { - self.0 as _ + self.0 as crate::ffi::c_ulong }
/// Check whether `flags` is contained in `self`. diff --git a/rust/kernel/drm/device.rs b/rust/kernel/drm/device.rs index ef66deb7ce23..b7ee3c464a12 100644 --- a/rust/kernel/drm/device.rs +++ b/rust/kernel/drm/device.rs @@ -89,7 +89,7 @@ impl<T: drm::Driver> Device<T> { driver_features: drm::driver::FEAT_GEM, ioctls: T::IOCTLS.as_ptr(), num_ioctls: T::IOCTLS.len() as i32, - fops: &Self::GEM_FOPS as _, + fops: &Self::GEM_FOPS, };
const GEM_FOPS: bindings::file_operations = drm::gem::create_fops(); diff --git a/rust/kernel/error.rs b/rust/kernel/error.rs index afcb00cb6a75..fd7a8b759437 100644 --- a/rust/kernel/error.rs +++ b/rust/kernel/error.rs @@ -153,7 +153,7 @@ pub(crate) fn to_blk_status(self) -> bindings::blk_status_t { /// Returns the error encoded as a pointer. pub fn to_ptr<T>(self) -> *mut T { // SAFETY: `self.0` is a valid error due to its invariant. - unsafe { bindings::ERR_PTR(self.0.get() as _).cast() } + unsafe { bindings::ERR_PTR(self.0.get() as isize).cast() } }
/// Returns a string representing the error, if one exists. diff --git a/rust/kernel/io.rs b/rust/kernel/io.rs index 72d80a6f131e..c08de4121637 100644 --- a/rust/kernel/io.rs +++ b/rust/kernel/io.rs @@ -5,7 +5,7 @@ //! C header: [`include/asm-generic/io.h`](srctree/include/asm-generic/io.h)
use crate::error::{code::EINVAL, Result}; -use crate::{bindings, build_assert}; +use crate::{bindings, build_assert, ffi::c_void};
/// Raw representation of an MMIO region. /// @@ -56,7 +56,7 @@ pub fn maxsize(&self) -> usize { /// # Examples /// /// ```no_run -/// # use kernel::{bindings, io::{Io, IoRaw}}; +/// # use kernel::{bindings, ffi::c_void, io::{Io, IoRaw}}; /// # use core::ops::Deref; /// /// // See also [`pci::Bar`] for a real example. @@ -70,19 +70,19 @@ pub fn maxsize(&self) -> usize { /// unsafe fn new(paddr: usize) -> Result<Self>{ /// // SAFETY: By the safety requirements of this function [`paddr`, `paddr` + `SIZE`) is /// // valid for `ioremap`. -/// let addr = unsafe { bindings::ioremap(paddr as _, SIZE as _) }; +/// let addr = unsafe { bindings::ioremap(paddr as bindings::phys_addr_t, SIZE) }; /// if addr.is_null() { /// return Err(ENOMEM); /// } /// -/// Ok(IoMem(IoRaw::new(addr as _, SIZE)?)) +/// Ok(IoMem(IoRaw::new(addr as usize, SIZE)?)) /// } /// } /// /// impl<const SIZE: usize> Drop for IoMem<SIZE> { /// fn drop(&mut self) { /// // SAFETY: `self.0.addr()` is guaranteed to be properly mapped by `Self::new`. -/// unsafe { bindings::iounmap(self.0.addr() as _); }; +/// unsafe { bindings::iounmap(self.0.addr() as *mut c_void); }; /// } /// } /// @@ -119,7 +119,7 @@ pub fn $name(&self, offset: usize) -> $type_name { let addr = self.io_addr_assert::<$type_name>(offset);
// SAFETY: By the type invariant `addr` is a valid address for MMIO operations. - unsafe { bindings::$c_fn(addr as _) } + unsafe { bindings::$c_fn(addr as *const c_void) } }
/// Read IO data from a given offset. @@ -131,7 +131,7 @@ pub fn $try_name(&self, offset: usize) -> Result<$type_name> { let addr = self.io_addr::<$type_name>(offset)?;
// SAFETY: By the type invariant `addr` is a valid address for MMIO operations. - Ok(unsafe { bindings::$c_fn(addr as _) }) + Ok(unsafe { bindings::$c_fn(addr as *const c_void) }) } }; } @@ -148,7 +148,7 @@ pub fn $name(&self, value: $type_name, offset: usize) { let addr = self.io_addr_assert::<$type_name>(offset);
// SAFETY: By the type invariant `addr` is a valid address for MMIO operations. - unsafe { bindings::$c_fn(value, addr as _, ) } + unsafe { bindings::$c_fn(value, addr as *mut c_void) } }
/// Write IO data from a given offset. @@ -160,7 +160,7 @@ pub fn $try_name(&self, value: $type_name, offset: usize) -> Result { let addr = self.io_addr::<$type_name>(offset)?;
// SAFETY: By the type invariant `addr` is a valid address for MMIO operations. - unsafe { bindings::$c_fn(value, addr as _) } + unsafe { bindings::$c_fn(value, addr as *mut c_void) } Ok(()) } }; diff --git a/rust/kernel/miscdevice.rs b/rust/kernel/miscdevice.rs index 939278bc7b03..288f40e79906 100644 --- a/rust/kernel/miscdevice.rs +++ b/rust/kernel/miscdevice.rs @@ -34,7 +34,7 @@ impl MiscDeviceOptions { pub const fn into_raw<T: MiscDevice>(self) -> bindings::miscdevice { // SAFETY: All zeros is valid for this C type. let mut result: bindings::miscdevice = unsafe { MaybeUninit::zeroed().assume_init() }; - result.minor = bindings::MISC_DYNAMIC_MINOR as _; + result.minor = bindings::MISC_DYNAMIC_MINOR as ffi::c_int; result.name = self.name.as_char_ptr(); result.fops = MiscdeviceVTable::<T>::build(); result diff --git a/rust/kernel/mm/virt.rs b/rust/kernel/mm/virt.rs index 31803674aecc..6086ca981b06 100644 --- a/rust/kernel/mm/virt.rs +++ b/rust/kernel/mm/virt.rs @@ -392,80 +392,80 @@ pub mod flags { use crate::bindings;
/// No flags are set. - pub const NONE: vm_flags_t = bindings::VM_NONE as _; + pub const NONE: vm_flags_t = bindings::VM_NONE as vm_flags_t;
/// Mapping allows reads. - pub const READ: vm_flags_t = bindings::VM_READ as _; + pub const READ: vm_flags_t = bindings::VM_READ as vm_flags_t;
/// Mapping allows writes. - pub const WRITE: vm_flags_t = bindings::VM_WRITE as _; + pub const WRITE: vm_flags_t = bindings::VM_WRITE as vm_flags_t;
/// Mapping allows execution. - pub const EXEC: vm_flags_t = bindings::VM_EXEC as _; + pub const EXEC: vm_flags_t = bindings::VM_EXEC as vm_flags_t;
/// Mapping is shared. - pub const SHARED: vm_flags_t = bindings::VM_SHARED as _; + pub const SHARED: vm_flags_t = bindings::VM_SHARED as vm_flags_t;
/// Mapping may be updated to allow reads. - pub const MAYREAD: vm_flags_t = bindings::VM_MAYREAD as _; + pub const MAYREAD: vm_flags_t = bindings::VM_MAYREAD as vm_flags_t;
/// Mapping may be updated to allow writes. - pub const MAYWRITE: vm_flags_t = bindings::VM_MAYWRITE as _; + pub const MAYWRITE: vm_flags_t = bindings::VM_MAYWRITE as vm_flags_t;
/// Mapping may be updated to allow execution. - pub const MAYEXEC: vm_flags_t = bindings::VM_MAYEXEC as _; + pub const MAYEXEC: vm_flags_t = bindings::VM_MAYEXEC as vm_flags_t;
/// Mapping may be updated to be shared. - pub const MAYSHARE: vm_flags_t = bindings::VM_MAYSHARE as _; + pub const MAYSHARE: vm_flags_t = bindings::VM_MAYSHARE as vm_flags_t;
/// Page-ranges managed without `struct page`, just pure PFN. - pub const PFNMAP: vm_flags_t = bindings::VM_PFNMAP as _; + pub const PFNMAP: vm_flags_t = bindings::VM_PFNMAP as vm_flags_t;
/// Memory mapped I/O or similar. - pub const IO: vm_flags_t = bindings::VM_IO as _; + pub const IO: vm_flags_t = bindings::VM_IO as vm_flags_t;
/// Do not copy this vma on fork. - pub const DONTCOPY: vm_flags_t = bindings::VM_DONTCOPY as _; + pub const DONTCOPY: vm_flags_t = bindings::VM_DONTCOPY as vm_flags_t;
/// Cannot expand with mremap(). - pub const DONTEXPAND: vm_flags_t = bindings::VM_DONTEXPAND as _; + pub const DONTEXPAND: vm_flags_t = bindings::VM_DONTEXPAND as vm_flags_t;
/// Lock the pages covered when they are faulted in. - pub const LOCKONFAULT: vm_flags_t = bindings::VM_LOCKONFAULT as _; + pub const LOCKONFAULT: vm_flags_t = bindings::VM_LOCKONFAULT as vm_flags_t;
/// Is a VM accounted object. - pub const ACCOUNT: vm_flags_t = bindings::VM_ACCOUNT as _; + pub const ACCOUNT: vm_flags_t = bindings::VM_ACCOUNT as vm_flags_t;
/// Should the VM suppress accounting. - pub const NORESERVE: vm_flags_t = bindings::VM_NORESERVE as _; + pub const NORESERVE: vm_flags_t = bindings::VM_NORESERVE as vm_flags_t;
/// Huge TLB Page VM. - pub const HUGETLB: vm_flags_t = bindings::VM_HUGETLB as _; + pub const HUGETLB: vm_flags_t = bindings::VM_HUGETLB as vm_flags_t;
/// Synchronous page faults. (DAX-specific) - pub const SYNC: vm_flags_t = bindings::VM_SYNC as _; + pub const SYNC: vm_flags_t = bindings::VM_SYNC as vm_flags_t;
/// Architecture-specific flag. - pub const ARCH_1: vm_flags_t = bindings::VM_ARCH_1 as _; + pub const ARCH_1: vm_flags_t = bindings::VM_ARCH_1 as vm_flags_t;
/// Wipe VMA contents in child on fork. - pub const WIPEONFORK: vm_flags_t = bindings::VM_WIPEONFORK as _; + pub const WIPEONFORK: vm_flags_t = bindings::VM_WIPEONFORK as vm_flags_t;
/// Do not include in the core dump. - pub const DONTDUMP: vm_flags_t = bindings::VM_DONTDUMP as _; + pub const DONTDUMP: vm_flags_t = bindings::VM_DONTDUMP as vm_flags_t;
/// Not soft dirty clean area. - pub const SOFTDIRTY: vm_flags_t = bindings::VM_SOFTDIRTY as _; + pub const SOFTDIRTY: vm_flags_t = bindings::VM_SOFTDIRTY as vm_flags_t;
/// Can contain `struct page` and pure PFN pages. - pub const MIXEDMAP: vm_flags_t = bindings::VM_MIXEDMAP as _; + pub const MIXEDMAP: vm_flags_t = bindings::VM_MIXEDMAP as vm_flags_t;
/// MADV_HUGEPAGE marked this vma. - pub const HUGEPAGE: vm_flags_t = bindings::VM_HUGEPAGE as _; + pub const HUGEPAGE: vm_flags_t = bindings::VM_HUGEPAGE as vm_flags_t;
/// MADV_NOHUGEPAGE marked this vma. - pub const NOHUGEPAGE: vm_flags_t = bindings::VM_NOHUGEPAGE as _; + pub const NOHUGEPAGE: vm_flags_t = bindings::VM_NOHUGEPAGE as vm_flags_t;
/// KSM may merge identical pages. - pub const MERGEABLE: vm_flags_t = bindings::VM_MERGEABLE as _; + pub const MERGEABLE: vm_flags_t = bindings::VM_MERGEABLE as vm_flags_t; } diff --git a/rust/kernel/of.rs b/rust/kernel/of.rs index 04f2d8ef29cb..40d1bd13682c 100644 --- a/rust/kernel/of.rs +++ b/rust/kernel/of.rs @@ -22,7 +22,7 @@ unsafe impl RawDeviceId for DeviceId { const DRIVER_DATA_OFFSET: usize = core::mem::offset_of!(bindings::of_device_id, data);
fn index(&self) -> usize { - self.0.data as _ + self.0.data as usize } }
@@ -34,10 +34,10 @@ pub const fn new(compatible: &'static CStr) -> Self { // SAFETY: FFI type is valid to be zero-initialized. let mut of: bindings::of_device_id = unsafe { core::mem::zeroed() };
- // TODO: Use `clone_from_slice` once the corresponding types do match. + // TODO: Use `copy_from_slice` once stabilized for `const`. let mut i = 0; while i < src.len() { - of.compatible[i] = src[i] as _; + of.compatible[i] = src[i]; i += 1; }
diff --git a/rust/kernel/pci.rs b/rust/kernel/pci.rs index 33ae0bdc433d..f6b19764ad17 100644 --- a/rust/kernel/pci.rs +++ b/rust/kernel/pci.rs @@ -171,7 +171,7 @@ unsafe impl RawDeviceId for DeviceId { const DRIVER_DATA_OFFSET: usize = core::mem::offset_of!(bindings::pci_device_id, driver_data);
fn index(&self) -> usize { - self.0.driver_data as _ + self.0.driver_data } }
@@ -206,7 +206,10 @@ macro_rules! pci_device_table { /// MODULE_PCI_TABLE, /// <MyDriver as pci::Driver>::IdInfo, /// [ -/// (pci::DeviceId::from_id(bindings::PCI_VENDOR_ID_REDHAT, bindings::PCI_ANY_ID as _), ()) +/// ( +/// pci::DeviceId::from_id(bindings::PCI_VENDOR_ID_REDHAT, bindings::PCI_ANY_ID as u32), +/// (), +/// ) /// ] /// ); /// @@ -330,7 +333,7 @@ unsafe fn do_release(pdev: &Device, ioptr: usize, num: i32) { // `ioptr` is valid by the safety requirements. // `num` is valid by the safety requirements. unsafe { - bindings::pci_iounmap(pdev.as_raw(), ioptr as _); + bindings::pci_iounmap(pdev.as_raw(), ioptr as *mut kernel::ffi::c_void); bindings::pci_release_region(pdev.as_raw(), num); } } diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs index 6a3cb607b332..43597eb7c5c1 100644 --- a/rust/kernel/str.rs +++ b/rust/kernel/str.rs @@ -728,9 +728,9 @@ fn new() -> Self { pub(crate) unsafe fn from_ptrs(pos: *mut u8, end: *mut u8) -> Self { // INVARIANT: The safety requirements guarantee the type invariants. Self { - beg: pos as _, - pos: pos as _, - end: end as _, + beg: pos as usize, + pos: pos as usize, + end: end as usize, } }
@@ -755,7 +755,7 @@ pub(crate) unsafe fn from_buffer(buf: *mut u8, len: usize) -> Self { /// /// N.B. It may point to invalid memory. pub(crate) fn pos(&self) -> *mut u8 { - self.pos as _ + self.pos as *mut u8 }
/// Returns the number of bytes written to the formatter. diff --git a/rust/kernel/workqueue.rs b/rust/kernel/workqueue.rs index de61374e36bd..89e5c2560eec 100644 --- a/rust/kernel/workqueue.rs +++ b/rust/kernel/workqueue.rs @@ -198,7 +198,7 @@ pub fn enqueue<W, const ID: u64>(&self, w: W) -> W::EnqueueOutput unsafe { w.__enqueue(move |work_ptr| { bindings::queue_work_on( - bindings::wq_misc_consts_WORK_CPU_UNBOUND as _, + bindings::wq_misc_consts_WORK_CPU_UNBOUND as ffi::c_int, queue_ptr, work_ptr, )