diff options
| -rw-r--r-- | rust/bindings/bindings_helper.h | 1 | ||||
| -rw-r--r-- | rust/helpers.c | 7 | ||||
| -rw-r--r-- | rust/kernel/error.rs | 39 |
3 files changed, 47 insertions, 0 deletions
diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h index 50e7a76d5455..3e601ce2548d 100644 --- a/rust/bindings/bindings_helper.h +++ b/rust/bindings/bindings_helper.h @@ -6,6 +6,7 @@ * Sorted alphabetically. */ +#include <linux/errname.h> #include <linux/slab.h> #include <linux/refcount.h> #include <linux/wait.h> diff --git a/rust/helpers.c b/rust/helpers.c index 81e80261d597..bb594da56137 100644 --- a/rust/helpers.c +++ b/rust/helpers.c @@ -21,6 +21,7 @@ #include <linux/bug.h> #include <linux/build_bug.h> #include <linux/err.h> +#include <linux/errname.h> #include <linux/refcount.h> #include <linux/mutex.h> #include <linux/spinlock.h> @@ -110,6 +111,12 @@ long rust_helper_PTR_ERR(__force const void *ptr) } EXPORT_SYMBOL_GPL(rust_helper_PTR_ERR); +const char *rust_helper_errname(int err) +{ + return errname(err); +} +EXPORT_SYMBOL_GPL(rust_helper_errname); + struct task_struct *rust_helper_get_current(void) { return current; diff --git a/rust/kernel/error.rs b/rust/kernel/error.rs index 7c1ce2bccd08..05fcab6abfe6 100644 --- a/rust/kernel/error.rs +++ b/rust/kernel/error.rs @@ -4,12 +4,15 @@ //! //! C header: [`include/uapi/asm-generic/errno-base.h`](../../../include/uapi/asm-generic/errno-base.h) +use crate::str::CStr; + use alloc::{ alloc::{AllocError, LayoutError}, collections::TryReserveError, }; use core::convert::From; +use core::fmt; use core::num::TryFromIntError; use core::str::Utf8Error; @@ -133,6 +136,42 @@ impl Error { // SAFETY: self.0 is a valid error due to its invariant. unsafe { bindings::ERR_PTR(self.0.into()) as *mut _ } } + + /// Returns a string representing the error, if one exists. + #[cfg(not(testlib))] + pub fn name(&self) -> Option<&'static CStr> { + // SAFETY: Just an FFI call, there are no extra safety requirements. + let ptr = unsafe { bindings::errname(-self.0) }; + if ptr.is_null() { + None + } else { + // SAFETY: The string returned by `errname` is static and `NUL`-terminated. + Some(unsafe { CStr::from_char_ptr(ptr) }) + } + } + + /// Returns a string representing the error, if one exists. + /// + /// When `testlib` is configured, this always returns `None` to avoid the dependency on a + /// kernel function so that tests that use this (e.g., by calling [`Result::unwrap`]) can still + /// run in userspace. + #[cfg(testlib)] + pub fn name(&self) -> Option<&'static CStr> { + None + } +} + +impl fmt::Debug for Error { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + match self.name() { + // Print out number if no name can be found. + None => f.debug_tuple("Error").field(&-self.0).finish(), + // SAFETY: These strings are ASCII-only. + Some(name) => f + .debug_tuple(unsafe { core::str::from_utf8_unchecked(name) }) + .finish(), + } + } } impl From<AllocError> for Error { |