diff options
Diffstat (limited to 'vendor/rustix/src/backend/linux_raw/arch/mod.rs')
| -rw-r--r-- | vendor/rustix/src/backend/linux_raw/arch/mod.rs | 317 |
1 files changed, 317 insertions, 0 deletions
diff --git a/vendor/rustix/src/backend/linux_raw/arch/mod.rs b/vendor/rustix/src/backend/linux_raw/arch/mod.rs new file mode 100644 index 0000000..ac9e25f --- /dev/null +++ b/vendor/rustix/src/backend/linux_raw/arch/mod.rs @@ -0,0 +1,317 @@ +//! Architecture-specific syscall code. +//! +//! This module also has a `choose` submodule which chooses a scheme and is +//! what most of the `rustix` syscalls use. +//! +//! Compilers should really have intrinsics for making system calls. They're +//! much like regular calls, with custom calling conventions, and calling +//! conventions are otherwise the compiler's job. But for now, use inline asm. +//! +//! The calling conventions for Linux syscalls are [documented here]. +//! +//! [documented here]: https://man7.org/linux/man-pages/man2/syscall.2.html +//! +//! # Safety +//! +//! This contains the inline `asm` statements performing the syscall +//! instructions. + +#![allow(unsafe_code)] +#![cfg_attr(not(feature = "all-apis"), allow(unused_imports))] +// We'll use as many arguments as syscalls need. +#![allow(clippy::too_many_arguments)] + +// These functions always use the machine's syscall instruction, even when it +// isn't the fastest option available. +#[cfg_attr(target_arch = "aarch64", path = "aarch64.rs")] +#[cfg_attr(all(target_arch = "arm", not(thumb_mode)), path = "arm.rs")] +#[cfg_attr(all(target_arch = "arm", thumb_mode), path = "thumb.rs")] +#[cfg_attr(target_arch = "mips", path = "mips.rs")] +#[cfg_attr(target_arch = "mips32r6", path = "mips32r6.rs")] +#[cfg_attr(target_arch = "mips64", path = "mips64.rs")] +#[cfg_attr(target_arch = "mips64r6", path = "mips64r6.rs")] +#[cfg_attr(target_arch = "powerpc64", path = "powerpc64.rs")] +#[cfg_attr(target_arch = "riscv64", path = "riscv64.rs")] +#[cfg_attr(target_arch = "x86", path = "x86.rs")] +#[cfg_attr(target_arch = "x86_64", path = "x86_64.rs")] +pub(in crate::backend) mod asm; + +// On most architectures, the architecture syscall instruction is fast, so use +// it directly. +#[cfg(any( + target_arch = "arm", + target_arch = "aarch64", + target_arch = "mips", + target_arch = "mips32r6", + target_arch = "mips64", + target_arch = "mips64r6", + target_arch = "powerpc64", + target_arch = "riscv64", + target_arch = "x86_64", +))] +pub(in crate::backend) use self::asm as choose; + +// On 32-bit x86, use vDSO wrappers for all syscalls. We could use the +// architecture syscall instruction (`int 0x80`), but the vDSO kernel_vsyscall +// mechanism is much faster. +#[cfg(target_arch = "x86")] +pub(in crate::backend) use super::vdso_wrappers::x86_via_vdso as choose; + +// This would be the code for always using `int 0x80` on 32-bit x86. +//#[cfg(target_arch = "x86")] +//pub(in crate::backend) use self::asm as choose; + +// Macros for invoking system calls. +// +// These factor out: +// - Calling `nr` on the syscall number to convert it into `SyscallNumber`. +// - Calling `.into()` on each of the arguments to convert them into `ArgReg`. +// - Qualifying the `syscall*` and `__NR_*` identifiers. +// - Counting the number of arguments. +macro_rules! syscall { + ($nr:ident) => { + $crate::backend::arch::choose::syscall0($crate::backend::reg::nr( + linux_raw_sys::general::$nr, + )) + }; + + ($nr:ident, $a0:expr) => { + $crate::backend::arch::choose::syscall1( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr) => { + $crate::backend::arch::choose::syscall2( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr) => { + $crate::backend::arch::choose::syscall3( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr, $a3:expr) => { + $crate::backend::arch::choose::syscall4( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + $a3.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr, $a3:expr, $a4:expr) => { + $crate::backend::arch::choose::syscall5( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + $a3.into(), + $a4.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr, $a3:expr, $a4:expr, $a5:expr) => { + $crate::backend::arch::choose::syscall6( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + $a3.into(), + $a4.into(), + $a5.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr, $a3:expr, $a4:expr, $a5:expr, $a6:expr) => { + $crate::backend::arch::choose::syscall7( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + $a3.into(), + $a4.into(), + $a5.into(), + $a6.into(), + ) + }; +} + +// Macro to invoke a syscall that always uses direct assembly, rather than the +// vDSO. Useful when still finding the vDSO. +#[allow(unused_macros)] +macro_rules! syscall_always_asm { + ($nr:ident) => { + $crate::backend::arch::asm::syscall0($crate::backend::reg::nr(linux_raw_sys::general::$nr)) + }; + + ($nr:ident, $a0:expr) => { + $crate::backend::arch::asm::syscall1( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr) => { + $crate::backend::arch::asm::syscall2( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr) => { + $crate::backend::arch::asm::syscall3( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr, $a3:expr) => { + $crate::backend::arch::asm::syscall4( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + $a3.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr, $a3:expr, $a4:expr) => { + $crate::backend::arch::asm::syscall5( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + $a3.into(), + $a4.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr, $a3:expr, $a4:expr, $a5:expr) => { + $crate::backend::arch::asm::syscall6( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + $a3.into(), + $a4.into(), + $a5.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr, $a3:expr, $a4:expr, $a5:expr, $a6:expr) => { + $crate::backend::arch::asm::syscall7( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + $a3.into(), + $a4.into(), + $a5.into(), + $a6.into(), + ) + }; +} + +/// Like `syscall`, but adds the `readonly` attribute to the inline asm, which +/// indicates that the syscall does not mutate any memory. +macro_rules! syscall_readonly { + ($nr:ident) => { + $crate::backend::arch::choose::syscall0_readonly($crate::backend::reg::nr( + linux_raw_sys::general::$nr, + )) + }; + + ($nr:ident, $a0:expr) => { + $crate::backend::arch::choose::syscall1_readonly( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr) => { + $crate::backend::arch::choose::syscall2_readonly( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr) => { + $crate::backend::arch::choose::syscall3_readonly( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr, $a3:expr) => { + $crate::backend::arch::choose::syscall4_readonly( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + $a3.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr, $a3:expr, $a4:expr) => { + $crate::backend::arch::choose::syscall5_readonly( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + $a3.into(), + $a4.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr, $a3:expr, $a4:expr, $a5:expr) => { + $crate::backend::arch::choose::syscall6_readonly( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + $a3.into(), + $a4.into(), + $a5.into(), + ) + }; + + ($nr:ident, $a0:expr, $a1:expr, $a2:expr, $a3:expr, $a4:expr, $a5:expr, $a6:expr) => { + $crate::backend::arch::choose::syscall7_readonly( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + $a1.into(), + $a2.into(), + $a3.into(), + $a4.into(), + $a5.into(), + $a6.into(), + ) + }; +} + +/// Like `syscall`, but indicates that the syscall does not return. +#[cfg(feature = "runtime")] +macro_rules! syscall_noreturn { + ($nr:ident, $a0:expr) => { + $crate::backend::arch::choose::syscall1_noreturn( + $crate::backend::reg::nr(linux_raw_sys::general::$nr), + $a0.into(), + ) + }; +} |