This patch adds uring_cmd() function for MiscDevice trait and its
callback implementation. It uses IoUringCmd that io_uring_cmd rust
abstraction.
Signed-off-by: Sidong Yang <sidong.yang@furiosa.ai>
---
rust/kernel/miscdevice.rs | 34 ++++++++++++++++++++++++++++++++++
1 file changed, 34 insertions(+)
diff --git a/rust/kernel/miscdevice.rs b/rust/kernel/miscdevice.rs
index 288f40e79906..5255faf27934 100644
--- a/rust/kernel/miscdevice.rs
+++ b/rust/kernel/miscdevice.rs
@@ -14,6 +14,7 @@
error::{to_result, Error, Result, VTABLE_DEFAULT_ERROR},
ffi::{c_int, c_long, c_uint, c_ulong},
fs::File,
+ io_uring::IoUringCmd,
mm::virt::VmaNew,
prelude::*,
seq_file::SeqFile,
@@ -175,6 +176,15 @@ fn show_fdinfo(
) {
build_error!(VTABLE_DEFAULT_ERROR)
}
+
+ fn uring_cmd(
+ _device: <Self::Ptr as ForeignOwnable>::Borrowed<'_>,
+ _file: &File,
+ _io_uring_cmd: &IoUringCmd,
+ issue_flags: u32,
+ ) -> Result<isize> {
+ build_error!(VTABLE_DEFAULT_ERROR)
+ }
}
/// A vtable for the file operations of a Rust miscdevice.
@@ -332,6 +342,25 @@ impl<T: MiscDevice> MiscdeviceVTable<T> {
T::show_fdinfo(device, m, file);
}
+ unsafe extern "C" fn uring_cmd(
+ ioucmd: *mut bindings::io_uring_cmd,
+ issue_flags: ffi::c_uint,
+ ) -> ffi::c_int {
+ // SAFETY: The file is valid for the duration of this call.
+ let ioucmd = unsafe { IoUringCmd::from_raw(ioucmd) };
+ let file = ioucmd.file();
+
+ // SAFETY: The file is valid for the duration of this call.
+ let private = unsafe { (*file.as_ptr()).private_data }.cast();
+ // SAFETY: Ioctl calls can borrow the private data of the file.
+ let device = unsafe { <T::Ptr as ForeignOwnable>::borrow(private) };
+
+ match T::uring_cmd(device, file, ioucmd, issue_flags) {
+ Ok(ret) => ret as ffi::c_int,
+ Err(err) => err.to_errno() as ffi::c_int,
+ }
+ }
+
const VTABLE: bindings::file_operations = bindings::file_operations {
open: Some(Self::open),
release: Some(Self::release),
@@ -354,6 +383,11 @@ impl<T: MiscDevice> MiscdeviceVTable<T> {
} else {
None
},
+ uring_cmd: if T::HAS_URING_CMD {
+ Some(Self::uring_cmd)
+ } else {
+ None
+ },
// SAFETY: All zeros is a valid value for `bindings::file_operations`.
..unsafe { MaybeUninit::zeroed().assume_init() }
};
--
2.43.0
On Sat, Jul 19, 2025 at 10:35 AM Sidong Yang <sidong.yang@furiosa.ai> wrote:
>
> This patch adds uring_cmd() function for MiscDevice trait and its
> callback implementation. It uses IoUringCmd that io_uring_cmd rust
> abstraction.
>
> Signed-off-by: Sidong Yang <sidong.yang@furiosa.ai>
> ---
> rust/kernel/miscdevice.rs | 34 ++++++++++++++++++++++++++++++++++
> 1 file changed, 34 insertions(+)
>
> diff --git a/rust/kernel/miscdevice.rs b/rust/kernel/miscdevice.rs
> index 288f40e79906..5255faf27934 100644
> --- a/rust/kernel/miscdevice.rs
> +++ b/rust/kernel/miscdevice.rs
> @@ -14,6 +14,7 @@
> error::{to_result, Error, Result, VTABLE_DEFAULT_ERROR},
> ffi::{c_int, c_long, c_uint, c_ulong},
> fs::File,
> + io_uring::IoUringCmd,
> mm::virt::VmaNew,
> prelude::*,
> seq_file::SeqFile,
> @@ -175,6 +176,15 @@ fn show_fdinfo(
> ) {
> build_error!(VTABLE_DEFAULT_ERROR)
> }
> +
> + fn uring_cmd(
> + _device: <Self::Ptr as ForeignOwnable>::Borrowed<'_>,
> + _file: &File,
> + _io_uring_cmd: &IoUringCmd,
> + issue_flags: u32,
> + ) -> Result<isize> {
Would i32 make more sense as the return value, since that's what
io_uring_cqe actually stores?
> + build_error!(VTABLE_DEFAULT_ERROR)
> + }
> }
>
> /// A vtable for the file operations of a Rust miscdevice.
> @@ -332,6 +342,25 @@ impl<T: MiscDevice> MiscdeviceVTable<T> {
> T::show_fdinfo(device, m, file);
> }
>
> + unsafe extern "C" fn uring_cmd(
> + ioucmd: *mut bindings::io_uring_cmd,
> + issue_flags: ffi::c_uint,
> + ) -> ffi::c_int {
> + // SAFETY: The file is valid for the duration of this call.
> + let ioucmd = unsafe { IoUringCmd::from_raw(ioucmd) };
> + let file = ioucmd.file();
> +
> + // SAFETY: The file is valid for the duration of this call.
> + let private = unsafe { (*file.as_ptr()).private_data }.cast();
> + // SAFETY: Ioctl calls can borrow the private data of the file.
"Ioctl" -> "uring cmd"?
Best,
Caleb
> + let device = unsafe { <T::Ptr as ForeignOwnable>::borrow(private) };
> +
> + match T::uring_cmd(device, file, ioucmd, issue_flags) {
> + Ok(ret) => ret as ffi::c_int,
> + Err(err) => err.to_errno() as ffi::c_int,
> + }
> + }
> +
> const VTABLE: bindings::file_operations = bindings::file_operations {
> open: Some(Self::open),
> release: Some(Self::release),
> @@ -354,6 +383,11 @@ impl<T: MiscDevice> MiscdeviceVTable<T> {
> } else {
> None
> },
> + uring_cmd: if T::HAS_URING_CMD {
> + Some(Self::uring_cmd)
> + } else {
> + None
> + },
> // SAFETY: All zeros is a valid value for `bindings::file_operations`.
> ..unsafe { MaybeUninit::zeroed().assume_init() }
> };
> --
> 2.43.0
>
>
On Sun, Jul 20, 2025 at 04:08:19PM -0400, Caleb Sander Mateos wrote:
> On Sat, Jul 19, 2025 at 10:35 AM Sidong Yang <sidong.yang@furiosa.ai> wrote:
> >
> > This patch adds uring_cmd() function for MiscDevice trait and its
> > callback implementation. It uses IoUringCmd that io_uring_cmd rust
> > abstraction.
> >
> > Signed-off-by: Sidong Yang <sidong.yang@furiosa.ai>
> > ---
> > rust/kernel/miscdevice.rs | 34 ++++++++++++++++++++++++++++++++++
> > 1 file changed, 34 insertions(+)
> >
> > diff --git a/rust/kernel/miscdevice.rs b/rust/kernel/miscdevice.rs
> > index 288f40e79906..5255faf27934 100644
> > --- a/rust/kernel/miscdevice.rs
> > +++ b/rust/kernel/miscdevice.rs
> > @@ -14,6 +14,7 @@
> > error::{to_result, Error, Result, VTABLE_DEFAULT_ERROR},
> > ffi::{c_int, c_long, c_uint, c_ulong},
> > fs::File,
> > + io_uring::IoUringCmd,
> > mm::virt::VmaNew,
> > prelude::*,
> > seq_file::SeqFile,
> > @@ -175,6 +176,15 @@ fn show_fdinfo(
> > ) {
> > build_error!(VTABLE_DEFAULT_ERROR)
> > }
> > +
> > + fn uring_cmd(
> > + _device: <Self::Ptr as ForeignOwnable>::Borrowed<'_>,
> > + _file: &File,
> > + _io_uring_cmd: &IoUringCmd,
> > + issue_flags: u32,
> > + ) -> Result<isize> {
>
> Would i32 make more sense as the return value, since that's what
> io_uring_cqe actually stores?
Agreed. thanks.
>
> > + build_error!(VTABLE_DEFAULT_ERROR)
> > + }
> > }
> >
> > /// A vtable for the file operations of a Rust miscdevice.
> > @@ -332,6 +342,25 @@ impl<T: MiscDevice> MiscdeviceVTable<T> {
> > T::show_fdinfo(device, m, file);
> > }
> >
> > + unsafe extern "C" fn uring_cmd(
> > + ioucmd: *mut bindings::io_uring_cmd,
> > + issue_flags: ffi::c_uint,
> > + ) -> ffi::c_int {
> > + // SAFETY: The file is valid for the duration of this call.
> > + let ioucmd = unsafe { IoUringCmd::from_raw(ioucmd) };
> > + let file = ioucmd.file();
> > +
> > + // SAFETY: The file is valid for the duration of this call.
> > + let private = unsafe { (*file.as_ptr()).private_data }.cast();
> > + // SAFETY: Ioctl calls can borrow the private data of the file.
>
> "Ioctl" -> "uring cmd"?
Thanks it's a bad mistake.
Thanks,
Sidong
>
> Best,
> Caleb
>
> > + let device = unsafe { <T::Ptr as ForeignOwnable>::borrow(private) };
> > +
> > + match T::uring_cmd(device, file, ioucmd, issue_flags) {
> > + Ok(ret) => ret as ffi::c_int,
> > + Err(err) => err.to_errno() as ffi::c_int,
> > + }
> > + }
> > +
> > const VTABLE: bindings::file_operations = bindings::file_operations {
> > open: Some(Self::open),
> > release: Some(Self::release),
> > @@ -354,6 +383,11 @@ impl<T: MiscDevice> MiscdeviceVTable<T> {
> > } else {
> > None
> > },
> > + uring_cmd: if T::HAS_URING_CMD {
> > + Some(Self::uring_cmd)
> > + } else {
> > + None
> > + },
> > // SAFETY: All zeros is a valid value for `bindings::file_operations`.
> > ..unsafe { MaybeUninit::zeroed().assume_init() }
> > };
> > --
> > 2.43.0
> >
> >
Hi Sidong, kernel test robot noticed the following build warnings: [auto build test WARNING on rust/rust-next] [also build test WARNING on char-misc/char-misc-testing char-misc/char-misc-next char-misc/char-misc-linus soc/for-next linus/master v6.16-rc6 next-20250718] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Sidong-Yang/rust-bindings-add-io_uring-headers-in-bindings_helper-h/20250719-223630 base: https://github.com/Rust-for-Linux/linux rust-next patch link: https://lore.kernel.org/r/20250719143358.22363-4-sidong.yang%40furiosa.ai patch subject: [PATCH 3/4] rust: miscdevice: add uring_cmd() for MiscDevice trait config: x86_64-rhel-9.4-rust (https://download.01.org/0day-ci/archive/20250721/202507210306.zCOB3QtO-lkp@intel.com/config) compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261) rustc: rustc 1.88.0 (6b00bc388 2025-06-23) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250721/202507210306.zCOB3QtO-lkp@intel.com/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202507210306.zCOB3QtO-lkp@intel.com/ All warnings (new ones prefixed by >>): >> warning: unused variable: `issue_flags` --> rust/kernel/miscdevice.rs:184:9 | 184 | issue_flags: u32, | ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_issue_flags` | = note: `#[warn(unused_variables)]` on by default -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
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