syscall.h (3903B)
1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * Access to user system call parameters and results 4 * 5 * Copyright IBM Corp. 2008 6 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) 7 */ 8 9#ifndef _ASM_SYSCALL_H 10#define _ASM_SYSCALL_H 1 11 12#include <uapi/linux/audit.h> 13#include <linux/sched.h> 14#include <linux/err.h> 15#include <asm/ptrace.h> 16 17extern const sys_call_ptr_t sys_call_table[]; 18extern const sys_call_ptr_t sys_call_table_emu[]; 19 20static inline long syscall_get_nr(struct task_struct *task, 21 struct pt_regs *regs) 22{ 23 return test_pt_regs_flag(regs, PIF_SYSCALL) ? 24 (regs->int_code & 0xffff) : -1; 25} 26 27static inline void syscall_rollback(struct task_struct *task, 28 struct pt_regs *regs) 29{ 30 regs->gprs[2] = regs->orig_gpr2; 31} 32 33static inline long syscall_get_error(struct task_struct *task, 34 struct pt_regs *regs) 35{ 36 unsigned long error = regs->gprs[2]; 37#ifdef CONFIG_COMPAT 38 if (test_tsk_thread_flag(task, TIF_31BIT)) { 39 /* 40 * Sign-extend the value so (int)-EFOO becomes (long)-EFOO 41 * and will match correctly in comparisons. 42 */ 43 error = (long)(int)error; 44 } 45#endif 46 return IS_ERR_VALUE(error) ? error : 0; 47} 48 49static inline long syscall_get_return_value(struct task_struct *task, 50 struct pt_regs *regs) 51{ 52 return regs->gprs[2]; 53} 54 55static inline void syscall_set_return_value(struct task_struct *task, 56 struct pt_regs *regs, 57 int error, long val) 58{ 59 set_pt_regs_flag(regs, PIF_SYSCALL_RET_SET); 60 regs->gprs[2] = error ? error : val; 61} 62 63static inline void syscall_get_arguments(struct task_struct *task, 64 struct pt_regs *regs, 65 unsigned long *args) 66{ 67 unsigned long mask = -1UL; 68 unsigned int n = 6; 69 70#ifdef CONFIG_COMPAT 71 if (test_tsk_thread_flag(task, TIF_31BIT)) 72 mask = 0xffffffff; 73#endif 74 while (n-- > 0) 75 if (n > 0) 76 args[n] = regs->gprs[2 + n] & mask; 77 78 args[0] = regs->orig_gpr2 & mask; 79} 80 81static inline int syscall_get_arch(struct task_struct *task) 82{ 83#ifdef CONFIG_COMPAT 84 if (test_tsk_thread_flag(task, TIF_31BIT)) 85 return AUDIT_ARCH_S390; 86#endif 87 return AUDIT_ARCH_S390X; 88} 89 90static inline bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs) 91{ 92 return false; 93} 94 95#define SYSCALL_FMT_0 96#define SYSCALL_FMT_1 , "0" (r2) 97#define SYSCALL_FMT_2 , "d" (r3) SYSCALL_FMT_1 98#define SYSCALL_FMT_3 , "d" (r4) SYSCALL_FMT_2 99#define SYSCALL_FMT_4 , "d" (r5) SYSCALL_FMT_3 100#define SYSCALL_FMT_5 , "d" (r6) SYSCALL_FMT_4 101#define SYSCALL_FMT_6 , "d" (r7) SYSCALL_FMT_5 102 103#define SYSCALL_PARM_0 104#define SYSCALL_PARM_1 , long arg1 105#define SYSCALL_PARM_2 SYSCALL_PARM_1, long arg2 106#define SYSCALL_PARM_3 SYSCALL_PARM_2, long arg3 107#define SYSCALL_PARM_4 SYSCALL_PARM_3, long arg4 108#define SYSCALL_PARM_5 SYSCALL_PARM_4, long arg5 109#define SYSCALL_PARM_6 SYSCALL_PARM_5, long arg6 110 111#define SYSCALL_REGS_0 112#define SYSCALL_REGS_1 \ 113 register long r2 asm("2") = arg1 114#define SYSCALL_REGS_2 \ 115 SYSCALL_REGS_1; \ 116 register long r3 asm("3") = arg2 117#define SYSCALL_REGS_3 \ 118 SYSCALL_REGS_2; \ 119 register long r4 asm("4") = arg3 120#define SYSCALL_REGS_4 \ 121 SYSCALL_REGS_3; \ 122 register long r5 asm("5") = arg4 123#define SYSCALL_REGS_5 \ 124 SYSCALL_REGS_4; \ 125 register long r6 asm("6") = arg5 126#define SYSCALL_REGS_6 \ 127 SYSCALL_REGS_5; \ 128 register long r7 asm("7") = arg6 129 130#define GENERATE_SYSCALL_FUNC(nr) \ 131static __always_inline \ 132long syscall##nr(unsigned long syscall SYSCALL_PARM_##nr) \ 133{ \ 134 register unsigned long r1 asm ("1") = syscall; \ 135 register long rc asm ("2"); \ 136 SYSCALL_REGS_##nr; \ 137 \ 138 asm volatile ( \ 139 " svc 0\n" \ 140 : "=d" (rc) \ 141 : "d" (r1) SYSCALL_FMT_##nr \ 142 : "memory"); \ 143 return rc; \ 144} 145 146GENERATE_SYSCALL_FUNC(0) 147GENERATE_SYSCALL_FUNC(1) 148GENERATE_SYSCALL_FUNC(2) 149GENERATE_SYSCALL_FUNC(3) 150GENERATE_SYSCALL_FUNC(4) 151GENERATE_SYSCALL_FUNC(5) 152GENERATE_SYSCALL_FUNC(6) 153 154#endif /* _ASM_SYSCALL_H */