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_rollback(struct task_struct *task, 34 struct pt_regs *regs) 35 { 36 regs->a0 = regs->orig_a0; 37 } 38 39 static inline long syscall_get_error(struct task_struct *task, 40 struct pt_regs *regs) 41 { 42 unsigned long error = regs->a0; 43 44 return IS_ERR_VALUE(error) ? error : 0; 45 } 46 47 static inline long syscall_get_return_value(struct task_struct *task, 48 struct pt_regs *regs) 49 { 50 return regs->a0; 51 } 52 53 static inline void syscall_set_return_value(struct task_struct *task, 54 struct pt_regs *regs, 55 int error, long val) 56 { 57 regs->a0 = (long) error ?: val; 58 } 59 60 static inline void syscall_get_arguments(struct task_struct *task, 61 struct pt_regs *regs, 62 unsigned long *args) 63 { 64 args[0] = regs->orig_a0; 65 args++; 66 memcpy(args, ®s->a1, 5 * sizeof(args[0])); 67 } 68 69 static inline int syscall_get_arch(struct task_struct *task) 70 { 71 #ifdef CONFIG_64BIT 72 return AUDIT_ARCH_RISCV64; 73 #else 74 return AUDIT_ARCH_RISCV32; 75 #endif 76 } 77 78 typedef long (*syscall_t)(const struct pt_regs *); 79 static inline void syscall_handler(struct pt_regs *regs, ulong syscall) 80 { 81 syscall_t fn; 82 83 #ifdef CONFIG_COMPAT 84 if ((regs->status & SR_UXL) == SR_UXL_32) 85 fn = compat_sys_call_table[syscall]; 86 else 87 #endif 88 fn = sys_call_table[syscall]; 89 90 regs->a0 = fn(regs); 91 } 92 93 static inline bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs) 94 { 95 return false; 96 } 97 98 asmlinkage long sys_riscv_flush_icache(uintptr_t, uintptr_t, uintptr_t); 99 100 asmlinkage long sys_riscv_hwprobe(struct riscv_hwprobe *, size_t, size_t, 101 unsigned long *, unsigned int); 102 #endif /* _ASM_RISCV_SYSCALL_H */ 103