Remove duplicate "have to" in comment
[linux-2.6] / include / asm-i386 / unwind.h
1 #ifndef _ASM_I386_UNWIND_H
2 #define _ASM_I386_UNWIND_H
3
4 /*
5  * Copyright (C) 2002-2006 Novell, Inc.
6  *      Jan Beulich <jbeulich@novell.com>
7  * This code is released under version 2 of the GNU GPL.
8  */
9
10 #ifdef CONFIG_STACK_UNWIND
11
12 #include <linux/sched.h>
13 #include <asm/fixmap.h>
14 #include <asm/ptrace.h>
15 #include <asm/uaccess.h>
16
17 struct unwind_frame_info
18 {
19         struct pt_regs regs;
20         struct task_struct *task;
21         unsigned call_frame:1;
22 };
23
24 #define UNW_PC(frame)        (frame)->regs.eip
25 #define UNW_SP(frame)        (frame)->regs.esp
26 #ifdef CONFIG_FRAME_POINTER
27 #define UNW_FP(frame)        (frame)->regs.ebp
28 #define FRAME_RETADDR_OFFSET 4
29 #define FRAME_LINK_OFFSET    0
30 #define STACK_BOTTOM(tsk)    STACK_LIMIT((tsk)->thread.esp0)
31 #define STACK_TOP(tsk)       ((tsk)->thread.esp0)
32 #else
33 #define UNW_FP(frame) ((void)(frame), 0)
34 #endif
35 #define STACK_LIMIT(ptr)     (((ptr) - 1) & ~(THREAD_SIZE - 1))
36
37 #define UNW_REGISTER_INFO \
38         PTREGS_INFO(eax), \
39         PTREGS_INFO(ecx), \
40         PTREGS_INFO(edx), \
41         PTREGS_INFO(ebx), \
42         PTREGS_INFO(esp), \
43         PTREGS_INFO(ebp), \
44         PTREGS_INFO(esi), \
45         PTREGS_INFO(edi), \
46         PTREGS_INFO(eip)
47
48 #define UNW_DEFAULT_RA(raItem, dataAlign) \
49         ((raItem).where == Memory && \
50          !((raItem).value * (dataAlign) + 4))
51
52 static inline void arch_unw_init_frame_info(struct unwind_frame_info *info,
53                                             /*const*/ struct pt_regs *regs)
54 {
55         if (user_mode_vm(regs))
56                 info->regs = *regs;
57         else {
58                 memcpy(&info->regs, regs, offsetof(struct pt_regs, esp));
59                 info->regs.esp = (unsigned long)&regs->esp;
60                 info->regs.xss = __KERNEL_DS;
61         }
62 }
63
64 static inline void arch_unw_init_blocked(struct unwind_frame_info *info)
65 {
66         memset(&info->regs, 0, sizeof(info->regs));
67         info->regs.eip = info->task->thread.eip;
68         info->regs.xcs = __KERNEL_CS;
69         __get_user(info->regs.ebp, (long *)info->task->thread.esp);
70         info->regs.esp = info->task->thread.esp;
71         info->regs.xss = __KERNEL_DS;
72         info->regs.xds = __USER_DS;
73         info->regs.xes = __USER_DS;
74         info->regs.xgs = __KERNEL_PDA;
75 }
76
77 extern asmlinkage int arch_unwind_init_running(struct unwind_frame_info *,
78                                                asmlinkage int (*callback)(struct unwind_frame_info *,
79                                                                           void *arg),
80                                                void *arg);
81
82 static inline int arch_unw_user_mode(/*const*/ struct unwind_frame_info *info)
83 {
84         return user_mode_vm(&info->regs)
85                || info->regs.eip < PAGE_OFFSET
86                || (info->regs.eip >= __fix_to_virt(FIX_VDSO)
87                    && info->regs.eip < __fix_to_virt(FIX_VDSO) + PAGE_SIZE)
88                || info->regs.esp < PAGE_OFFSET;
89 }
90
91 #else
92
93 #define UNW_PC(frame) ((void)(frame), 0)
94 #define UNW_SP(frame) ((void)(frame), 0)
95 #define UNW_FP(frame) ((void)(frame), 0)
96
97 static inline int arch_unw_user_mode(const void *info)
98 {
99         return 0;
100 }
101
102 #endif
103
104 #endif /* _ASM_I386_UNWIND_H */