| Martin Schwidefsky | 753c4dd | 2008-10-10 21:33:20 +0200 | [diff] [blame^] | 1 | /* |
| 2 | * Access to user system call parameters and results |
| 3 | * |
| 4 | * Copyright IBM Corp. 2008 |
| 5 | * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License (version 2 only) |
| 9 | * as published by the Free Software Foundation. |
| 10 | */ |
| 11 | |
| 12 | #ifndef _ASM_SYSCALL_H |
| 13 | #define _ASM_SYSCALL_H 1 |
| 14 | |
| 15 | #include <asm/ptrace.h> |
| 16 | |
| 17 | static inline long syscall_get_nr(struct task_struct *task, |
| 18 | struct pt_regs *regs) |
| 19 | { |
| 20 | if (regs->trap != __LC_SVC_OLD_PSW) |
| 21 | return -1; |
| 22 | return regs->gprs[2]; |
| 23 | } |
| 24 | |
| 25 | static inline void syscall_rollback(struct task_struct *task, |
| 26 | struct pt_regs *regs) |
| 27 | { |
| 28 | regs->gprs[2] = regs->orig_gpr2; |
| 29 | } |
| 30 | |
| 31 | static inline long syscall_get_error(struct task_struct *task, |
| 32 | struct pt_regs *regs) |
| 33 | { |
| 34 | return (regs->gprs[2] >= -4096UL) ? -regs->gprs[2] : 0; |
| 35 | } |
| 36 | |
| 37 | static inline long syscall_get_return_value(struct task_struct *task, |
| 38 | struct pt_regs *regs) |
| 39 | { |
| 40 | return regs->gprs[2]; |
| 41 | } |
| 42 | |
| 43 | static inline void syscall_set_return_value(struct task_struct *task, |
| 44 | struct pt_regs *regs, |
| 45 | int error, long val) |
| 46 | { |
| 47 | regs->gprs[2] = error ? -error : val; |
| 48 | } |
| 49 | |
| 50 | static inline void syscall_get_arguments(struct task_struct *task, |
| 51 | struct pt_regs *regs, |
| 52 | unsigned int i, unsigned int n, |
| 53 | unsigned long *args) |
| 54 | { |
| 55 | BUG_ON(i + n > 6); |
| 56 | #ifdef CONFIG_COMPAT |
| 57 | if (test_tsk_thread_flag(task, TIF_31BIT)) { |
| 58 | if (i + n == 6) |
| 59 | args[--n] = (u32) regs->args[0]; |
| 60 | while (n-- > 0) |
| 61 | args[n] = (u32) regs->gprs[2 + i + n]; |
| 62 | } |
| 63 | #endif |
| 64 | if (i + n == 6) |
| 65 | args[--n] = regs->args[0]; |
| 66 | memcpy(args, ®s->gprs[2 + i], n * sizeof(args[0])); |
| 67 | } |
| 68 | |
| 69 | static inline void syscall_set_arguments(struct task_struct *task, |
| 70 | struct pt_regs *regs, |
| 71 | unsigned int i, unsigned int n, |
| 72 | const unsigned long *args) |
| 73 | { |
| 74 | BUG_ON(i + n > 6); |
| 75 | if (i + n == 6) |
| 76 | regs->args[0] = args[--n]; |
| 77 | memcpy(®s->gprs[2 + i], args, n * sizeof(args[0])); |
| 78 | } |
| 79 | |
| 80 | #endif /* _ASM_SYSCALL_H */ |