1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved. 4 * Copyright 2010 Tilera Corporation. All Rights Reserved. 5 * Copyright 2015 Regents of the University of California, Berkeley 6 * 7 * See asm-generic/syscall.h for descriptions of what we must do here. 8 */ 9 10 #ifndef _ASM_RISCV_SYSCALL_H 11 #define _ASM_RISCV_SYSCALL_H 12 13 #include <asm/hwprobe.h> 14 #include <uapi/linux/audit.h> 15 #include <linux/sched.h> 16 #include <linux/err.h> 17 18 /* The array of function pointers for syscalls. */ 19 extern void * const sys_call_table[]; 20 extern void * const compat_sys_call_table[]; 21 22 /* 23 * Only the low 32 bits of orig_r0 are meaningful, so we return int. 24 * This importantly ignores the high bits on 64-bit, so comparisons 25 * sign-extend the low 32 bits. 26 */ 27 static inline int syscall_get_nr(struct task_struct *task, 28 struct pt_regs *regs) 29 { 30 return regs->a7; 31 } 32 33 static inline void syscall_set_nr(struct task_struct *task, 34 struct pt_regs *regs, 35 int nr) 36 { 37 regs->a7 = nr; 38 } 39 40 static inline void syscall_rollback(struct task_struct *task, 41 struct pt_regs *regs) 42 { 43 regs->a0 = regs->orig_a0; 44 } 45 46 static inline long syscall_get_error(struct task_struct *task, 47 struct pt_regs *regs) 48 { 49 unsigned long error = regs->a0; 50 51 return IS_ERR_VALUE(error) ? error : 0; 52 } 53 54 static inline long syscall_get_return_value(struct task_struct *task, 55 struct pt_regs *regs) 56 { 57 return regs->a0; 58 } 59 60 static inline void syscall_set_return_value(struct task_struct *task, 61 struct pt_regs *regs, 62 int error, long val) 63 { 64 regs->a0 = (long) error ?: val; 65 } 66 67 static inline void syscall_get_arguments(struct task_struct *task, 68 struct pt_regs *regs, 69 unsigned long *args) 70 { 71 args[0] = regs->orig_a0; 72 args[1] = regs->a1; 73 args[2] = regs->a2; 74 args[3] = regs->a3; 75 args[4] = regs->a4; 76 args[5] = regs->a5; 77 } 78 79 static inline void syscall_set_arguments(struct task_struct *task, 80 struct pt_regs *regs, 81 const unsigned long *args) 82 { 83 regs->orig_a0 = args[0]; 84 regs->a1 = args[1]; 85 regs->a2 = args[2]; 86 regs->a3 = args[3]; 87 regs->a4 = args[4]; 88 regs->a5 = args[5]; 89 } 90 91 static inline int syscall_get_arch(struct task_struct *task) 92 { 93 #ifdef CONFIG_64BIT 94 return AUDIT_ARCH_RISCV64; 95 #else 96 return AUDIT_ARCH_RISCV32; 97 #endif 98 } 99 100 typedef long (*syscall_t)(const struct pt_regs *); 101 static inline void syscall_handler(struct pt_regs *regs, ulong syscall) 102 { 103 syscall_t fn; 104 105 #ifdef CONFIG_COMPAT 106 if ((regs->status & SR_UXL) == SR_UXL_32) 107 fn = compat_sys_call_table[syscall]; 108 else 109 #endif 110 fn = sys_call_table[syscall]; 111 112 regs->a0 = fn(regs); 113 } 114 115 static inline bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs) 116 { 117 return false; 118 } 119 120 asmlinkage long sys_riscv_flush_icache(uintptr_t, uintptr_t, uintptr_t); 121 122 asmlinkage long sys_riscv_hwprobe(struct riscv_hwprobe *, size_t, size_t, 123 unsigned long *, unsigned int); 124 #endif /* _ASM_RISCV_SYSCALL_H */ 125