| /* |
| * Copyright (c) 2019 Intel Corporation. |
| * |
| * SPDX-License-Identifier: Apache-2.0 |
| */ |
| |
| /** |
| * @file |
| * @brief x86 (INTEL64) specific sycall header |
| * |
| * This header contains the x86 specific sycall interface. It is |
| * included by the syscall interface architecture-abstraction header |
| * (include/arch/syscall.h) |
| */ |
| |
| #ifndef ZEPHYR_INCLUDE_ARCH_X86_INTEL64_SYSCALL_H_ |
| #define ZEPHYR_INCLUDE_ARCH_X86_INTEL64_SYSCALL_H_ |
| |
| #ifdef CONFIG_USERSPACE |
| #ifndef _ASMLANGUAGE |
| |
| #include <zephyr/types.h> |
| #include <stdbool.h> |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| /* |
| * x86_64 System V calling convention: |
| * First six arguments passed in via RDI, RSI, RDX, RCX, R8, R9 |
| * We'll use RAX for the call_id, and the return value |
| * |
| * Arrange registers so that they are in-place as much as possible when |
| * doing the system call. Because RCX get overwritten by the CPU, put arg 4 |
| * in r10 instead. |
| * |
| * SYSCALL instruction stores return address in RCX and RFLAGS in R11. RIP is |
| * loaded from LSTAR MSR, masks RFLAGS with the low 32 bits of EFER.SFMASK. CS |
| * and SS are loaded from values derived from bits 47:32 of STAR MSR (+0 |
| * for CS, +8 for SS) |
| * |
| * SYSRET loads RIP from RCX and RFLAGS from r11. CS and SS are set with |
| * values derived from STAR MSR bits 63:48 (+8 for CS, +16 for SS) |
| * |
| * The kernel is in charge of not clobbering across the system call |
| * the remaining registers: RBX, RBP, R12-R15, SIMD/FPU, and any unused |
| * argument registers. |
| */ |
| static inline uintptr_t arch_syscall_invoke6(uintptr_t arg1, uintptr_t arg2, |
| uintptr_t arg3, uintptr_t arg4, |
| uintptr_t arg5, uintptr_t arg6, |
| uintptr_t call_id) |
| { |
| register uintptr_t rax __asm__("%rax") = call_id; |
| register uintptr_t rdi __asm__("%rdi") = arg1; |
| register uintptr_t rsi __asm__("%rsi") = arg2; |
| register uintptr_t rdx __asm__("%rdx") = arg3; |
| register uintptr_t r10 __asm__("%r10") = arg4; /* RCX unavailable */ |
| register uintptr_t r8 __asm__("%r8") = arg5; |
| register uintptr_t r9 __asm__("%r9") = arg6; |
| |
| __asm__ volatile("syscall\n\t" |
| : "=r" (rax) |
| : "r" (rax), "r" (rdi), "r" (rsi), "r" (rdx), |
| "r" (r10), "r" (r8), "r" (r9) |
| : "memory", "rcx", "r11"); |
| |
| return rax; |
| } |
| |
| static inline uintptr_t arch_syscall_invoke5(uintptr_t arg1, uintptr_t arg2, |
| uintptr_t arg3, uintptr_t arg4, |
| uintptr_t arg5, |
| uintptr_t call_id) |
| { |
| register uintptr_t rax __asm__("%rax") = call_id; |
| register uintptr_t rdi __asm__("%rdi") = arg1; |
| register uintptr_t rsi __asm__("%rsi") = arg2; |
| register uintptr_t rdx __asm__("%rdx") = arg3; |
| register uintptr_t r10 __asm__("%r10") = arg4; /* RCX unavailable */ |
| register uintptr_t r8 __asm__("%r8") = arg5; |
| |
| __asm__ volatile("syscall\n\t" |
| : "=r" (rax) |
| : "r" (rax), "r" (rdi), "r" (rsi), "r" (rdx), |
| "r" (r10), "r" (r8) |
| : "memory", "rcx", "r11"); |
| |
| return rax; |
| } |
| |
| static inline uintptr_t arch_syscall_invoke4(uintptr_t arg1, uintptr_t arg2, |
| uintptr_t arg3, uintptr_t arg4, |
| uintptr_t call_id) |
| { |
| register uintptr_t rax __asm__("%rax") = call_id; |
| register uintptr_t rdi __asm__("%rdi") = arg1; |
| register uintptr_t rsi __asm__("%rsi") = arg2; |
| register uintptr_t rdx __asm__("%rdx") = arg3; |
| register uintptr_t r10 __asm__("%r10") = arg4; /* RCX unavailable */ |
| |
| __asm__ volatile("syscall\n\t" |
| : "=r" (rax) |
| : "r" (rax), "r" (rdi), "r" (rsi), "r" (rdx), |
| "r" (r10) |
| : "memory", "rcx", "r11"); |
| |
| return rax; |
| } |
| |
| static inline uintptr_t arch_syscall_invoke3(uintptr_t arg1, uintptr_t arg2, |
| uintptr_t arg3, |
| uintptr_t call_id) |
| { |
| register uintptr_t rax __asm__("%rax") = call_id; |
| register uintptr_t rdi __asm__("%rdi") = arg1; |
| register uintptr_t rsi __asm__("%rsi") = arg2; |
| register uintptr_t rdx __asm__("%rdx") = arg3; |
| |
| __asm__ volatile("syscall\n\t" |
| : "=r" (rax) |
| : "r" (rax), "r" (rdi), "r" (rsi), "r" (rdx) |
| : "memory", "rcx", "r11"); |
| |
| return rax; |
| } |
| |
| static inline uintptr_t arch_syscall_invoke2(uintptr_t arg1, uintptr_t arg2, |
| uintptr_t call_id) |
| |
| { |
| register uintptr_t rax __asm__("%rax") = call_id; |
| register uintptr_t rdi __asm__("%rdi") = arg1; |
| register uintptr_t rsi __asm__("%rsi") = arg2; |
| |
| __asm__ volatile("syscall\n\t" |
| : "=r" (rax) |
| : "r" (rax), "r" (rdi), "r" (rsi) |
| : "memory", "rcx", "r11"); |
| |
| return rax; |
| } |
| |
| static inline uintptr_t arch_syscall_invoke1(uintptr_t arg1, |
| uintptr_t call_id) |
| { |
| register uintptr_t rax __asm__("%rax") = call_id; |
| register uintptr_t rdi __asm__("%rdi") = arg1; |
| |
| __asm__ volatile("syscall\n\t" |
| : "=r" (rax) |
| : "r" (rax), "r" (rdi) |
| : "memory", "rcx", "r11"); |
| |
| return rax; |
| } |
| |
| static inline uintptr_t arch_syscall_invoke0(uintptr_t call_id) |
| { |
| register uintptr_t rax __asm__("%rax") = call_id; |
| |
| __asm__ volatile("syscall\n\t" |
| : "=r" (rax) |
| : "r" (rax) |
| : "memory", "rcx", "r11"); |
| |
| return rax; |
| } |
| |
| static inline bool arch_is_user_context(void) |
| { |
| uint32_t cs; |
| |
| __asm__ volatile ("mov %%cs, %[cs_val]" : [cs_val] "=r" (cs)); |
| |
| return (cs & 0x3) != 0; |
| } |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* _ASMLANGUAGE */ |
| #endif /* CONFIG_USERSPACE */ |
| #endif /* ZEPHYR_INCLUDE_ARCH_X86_INTEL64_SYSCALL_H_ */ |