Mickaël Salaün | d8f8b84 | 2015-12-29 21:35:46 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Access to user system call parameters and results |
| 3 | * |
| 4 | * See asm-generic/syscall.h for function descriptions. |
| 5 | * |
| 6 | * Copyright (C) 2015 Mickaël Salaün <mic@digikod.net> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License version 2 as |
| 10 | * published by the Free Software Foundation. |
| 11 | */ |
| 12 | |
| 13 | #ifndef __UM_SYSCALL_GENERIC_H |
| 14 | #define __UM_SYSCALL_GENERIC_H |
| 15 | |
| 16 | #include <asm/ptrace.h> |
| 17 | #include <linux/err.h> |
| 18 | #include <linux/sched.h> |
| 19 | #include <sysdep/ptrace.h> |
| 20 | |
| 21 | static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs) |
| 22 | { |
| 23 | |
| 24 | return PT_REGS_SYSCALL_NR(regs); |
| 25 | } |
| 26 | |
| 27 | static inline void syscall_rollback(struct task_struct *task, |
| 28 | struct pt_regs *regs) |
| 29 | { |
| 30 | /* do nothing */ |
| 31 | } |
| 32 | |
| 33 | static inline long syscall_get_error(struct task_struct *task, |
| 34 | struct pt_regs *regs) |
| 35 | { |
| 36 | const long error = regs_return_value(regs); |
| 37 | |
| 38 | return IS_ERR_VALUE(error) ? error : 0; |
| 39 | } |
| 40 | |
| 41 | static inline long syscall_get_return_value(struct task_struct *task, |
| 42 | struct pt_regs *regs) |
| 43 | { |
| 44 | return regs_return_value(regs); |
| 45 | } |
| 46 | |
| 47 | static inline void syscall_set_return_value(struct task_struct *task, |
| 48 | struct pt_regs *regs, |
| 49 | int error, long val) |
| 50 | { |
| 51 | PT_REGS_SET_SYSCALL_RETURN(regs, (long) error ?: val); |
| 52 | } |
| 53 | |
| 54 | static inline void syscall_get_arguments(struct task_struct *task, |
| 55 | struct pt_regs *regs, |
| 56 | unsigned int i, unsigned int n, |
| 57 | unsigned long *args) |
| 58 | { |
| 59 | const struct uml_pt_regs *r = ®s->regs; |
| 60 | |
| 61 | switch (i) { |
| 62 | case 0: |
| 63 | if (!n--) |
| 64 | break; |
| 65 | *args++ = UPT_SYSCALL_ARG1(r); |
| 66 | case 1: |
| 67 | if (!n--) |
| 68 | break; |
| 69 | *args++ = UPT_SYSCALL_ARG2(r); |
| 70 | case 2: |
| 71 | if (!n--) |
| 72 | break; |
| 73 | *args++ = UPT_SYSCALL_ARG3(r); |
| 74 | case 3: |
| 75 | if (!n--) |
| 76 | break; |
| 77 | *args++ = UPT_SYSCALL_ARG4(r); |
| 78 | case 4: |
| 79 | if (!n--) |
| 80 | break; |
| 81 | *args++ = UPT_SYSCALL_ARG5(r); |
| 82 | case 5: |
| 83 | if (!n--) |
| 84 | break; |
| 85 | *args++ = UPT_SYSCALL_ARG6(r); |
| 86 | case 6: |
| 87 | if (!n--) |
| 88 | break; |
| 89 | default: |
| 90 | BUG(); |
| 91 | break; |
| 92 | } |
| 93 | } |
| 94 | |
| 95 | static inline void syscall_set_arguments(struct task_struct *task, |
| 96 | struct pt_regs *regs, |
| 97 | unsigned int i, unsigned int n, |
| 98 | const unsigned long *args) |
| 99 | { |
| 100 | struct uml_pt_regs *r = ®s->regs; |
| 101 | |
| 102 | switch (i) { |
| 103 | case 0: |
| 104 | if (!n--) |
| 105 | break; |
| 106 | UPT_SYSCALL_ARG1(r) = *args++; |
| 107 | case 1: |
| 108 | if (!n--) |
| 109 | break; |
| 110 | UPT_SYSCALL_ARG2(r) = *args++; |
| 111 | case 2: |
| 112 | if (!n--) |
| 113 | break; |
| 114 | UPT_SYSCALL_ARG3(r) = *args++; |
| 115 | case 3: |
| 116 | if (!n--) |
| 117 | break; |
| 118 | UPT_SYSCALL_ARG4(r) = *args++; |
| 119 | case 4: |
| 120 | if (!n--) |
| 121 | break; |
| 122 | UPT_SYSCALL_ARG5(r) = *args++; |
| 123 | case 5: |
| 124 | if (!n--) |
| 125 | break; |
| 126 | UPT_SYSCALL_ARG6(r) = *args++; |
| 127 | case 6: |
| 128 | if (!n--) |
| 129 | break; |
| 130 | default: |
| 131 | BUG(); |
| 132 | break; |
| 133 | } |
| 134 | } |
| 135 | |
| 136 | /* See arch/x86/um/asm/syscall.h for syscall_get_arch() definition. */ |
| 137 | |
| 138 | #endif /* __UM_SYSCALL_GENERIC_H */ |