Roland McGrath | f1ba128 | 2008-07-27 16:51:35 +1000 | [diff] [blame] | 1 | /* |
| 2 | * Access to user system call parameters and results |
| 3 | * |
| 4 | * Copyright (C) 2008 Red Hat, Inc. All rights reserved. |
| 5 | * |
| 6 | * This copyrighted material is made available to anyone wishing to use, |
| 7 | * modify, copy, or redistribute it subject to the terms and conditions |
| 8 | * of the GNU General Public License v.2. |
| 9 | * |
| 10 | * See asm-generic/syscall.h for descriptions of what we must do here. |
| 11 | */ |
| 12 | |
| 13 | #ifndef _ASM_SYSCALL_H |
| 14 | #define _ASM_SYSCALL_H 1 |
| 15 | |
| 16 | #include <linux/sched.h> |
| 17 | |
| 18 | static inline long syscall_get_nr(struct task_struct *task, |
| 19 | struct pt_regs *regs) |
| 20 | { |
| 21 | return TRAP(regs) == 0xc00 ? regs->gpr[0] : -1L; |
| 22 | } |
| 23 | |
| 24 | static inline void syscall_rollback(struct task_struct *task, |
| 25 | struct pt_regs *regs) |
| 26 | { |
| 27 | regs->gpr[3] = regs->orig_gpr3; |
| 28 | } |
| 29 | |
| 30 | static inline long syscall_get_error(struct task_struct *task, |
| 31 | struct pt_regs *regs) |
| 32 | { |
Nathan Lynch | 409d241 | 2010-03-12 13:16:02 +0000 | [diff] [blame] | 33 | return (regs->ccr & 0x10000000) ? -regs->gpr[3] : 0; |
Roland McGrath | f1ba128 | 2008-07-27 16:51:35 +1000 | [diff] [blame] | 34 | } |
| 35 | |
| 36 | static inline long syscall_get_return_value(struct task_struct *task, |
| 37 | struct pt_regs *regs) |
| 38 | { |
| 39 | return regs->gpr[3]; |
| 40 | } |
| 41 | |
| 42 | static inline void syscall_set_return_value(struct task_struct *task, |
| 43 | struct pt_regs *regs, |
| 44 | int error, long val) |
| 45 | { |
| 46 | if (error) { |
Nathan Lynch | 409d241 | 2010-03-12 13:16:02 +0000 | [diff] [blame] | 47 | regs->ccr |= 0x10000000L; |
Roland McGrath | f1ba128 | 2008-07-27 16:51:35 +1000 | [diff] [blame] | 48 | regs->gpr[3] = -error; |
| 49 | } else { |
Nathan Lynch | 409d241 | 2010-03-12 13:16:02 +0000 | [diff] [blame] | 50 | regs->ccr &= ~0x10000000L; |
Roland McGrath | f1ba128 | 2008-07-27 16:51:35 +1000 | [diff] [blame] | 51 | regs->gpr[3] = val; |
| 52 | } |
| 53 | } |
| 54 | |
| 55 | static inline void syscall_get_arguments(struct task_struct *task, |
| 56 | struct pt_regs *regs, |
| 57 | unsigned int i, unsigned int n, |
| 58 | unsigned long *args) |
| 59 | { |
| 60 | BUG_ON(i + n > 6); |
| 61 | #ifdef CONFIG_PPC64 |
| 62 | if (test_tsk_thread_flag(task, TIF_32BIT)) { |
| 63 | /* |
| 64 | * Zero-extend 32-bit argument values. The high bits are |
| 65 | * garbage ignored by the actual syscall dispatch. |
| 66 | */ |
| 67 | while (n-- > 0) |
| 68 | args[n] = (u32) regs->gpr[3 + i + n]; |
| 69 | return; |
| 70 | } |
| 71 | #endif |
| 72 | memcpy(args, ®s->gpr[3 + i], n * sizeof(args[0])); |
| 73 | } |
| 74 | |
| 75 | static inline void syscall_set_arguments(struct task_struct *task, |
| 76 | struct pt_regs *regs, |
| 77 | unsigned int i, unsigned int n, |
| 78 | const unsigned long *args) |
| 79 | { |
| 80 | BUG_ON(i + n > 6); |
| 81 | memcpy(®s->gpr[3 + i], args, n * sizeof(args[0])); |
| 82 | } |
| 83 | |
| 84 | #endif /* _ASM_SYSCALL_H */ |