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 <uapi/linux/audit.h> 17 #include <linux/sched.h> 18 #include <linux/thread_info.h> 19 20 /* ftrace syscalls requires exporting the sys_call_table */ 21 #ifdef CONFIG_FTRACE_SYSCALLS 22 extern const unsigned long sys_call_table[]; 23 #endif /* CONFIG_FTRACE_SYSCALLS */ 24 25 static inline long syscall_get_nr(struct task_struct *task, 26 struct pt_regs *regs) 27 { 28 return TRAP(regs) == 0xc00 ? regs->gpr[0] : -1L; 29 } 30 31 static inline void syscall_rollback(struct task_struct *task, 32 struct pt_regs *regs) 33 { 34 regs->gpr[3] = regs->orig_gpr3; 35 } 36 37 static inline long syscall_get_error(struct task_struct *task, 38 struct pt_regs *regs) 39 { 40 return (regs->ccr & 0x10000000) ? -regs->gpr[3] : 0; 41 } 42 43 static inline long syscall_get_return_value(struct task_struct *task, 44 struct pt_regs *regs) 45 { 46 return regs->gpr[3]; 47 } 48 49 static inline void syscall_set_return_value(struct task_struct *task, 50 struct pt_regs *regs, 51 int error, long val) 52 { 53 if (error) { 54 regs->ccr |= 0x10000000L; 55 regs->gpr[3] = -error; 56 } else { 57 regs->ccr &= ~0x10000000L; 58 regs->gpr[3] = val; 59 } 60 } 61 62 static inline void syscall_get_arguments(struct task_struct *task, 63 struct pt_regs *regs, 64 unsigned int i, unsigned int n, 65 unsigned long *args) 66 { 67 BUG_ON(i + n > 6); 68 #ifdef CONFIG_PPC64 69 if (test_tsk_thread_flag(task, TIF_32BIT)) { 70 /* 71 * Zero-extend 32-bit argument values. The high bits are 72 * garbage ignored by the actual syscall dispatch. 73 */ 74 while (n-- > 0) 75 args[n] = (u32) regs->gpr[3 + i + n]; 76 return; 77 } 78 #endif 79 memcpy(args, ®s->gpr[3 + i], n * sizeof(args[0])); 80 } 81 82 static inline void syscall_set_arguments(struct task_struct *task, 83 struct pt_regs *regs, 84 unsigned int i, unsigned int n, 85 const unsigned long *args) 86 { 87 BUG_ON(i + n > 6); 88 memcpy(®s->gpr[3 + i], args, n * sizeof(args[0])); 89 } 90 91 static inline int syscall_get_arch(void) 92 { 93 int arch = is_32bit_task() ? AUDIT_ARCH_PPC : AUDIT_ARCH_PPC64; 94 #ifdef __LITTLE_ENDIAN__ 95 arch |= __AUDIT_ARCH_LE; 96 #endif 97 return arch; 98 } 99 #endif /* _ASM_SYSCALL_H */ 100