[PATCH] i386/x86-64: Work around gcc bug with noreturn functions in unwinder
[linux-2.6.git] / 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 }
75
76 extern asmlinkage int arch_unwind_init_running(struct unwind_frame_info *,
77                                                asmlinkage int (*callback)(struct unwind_frame_info *,
78                                                                           void *arg),
79                                                void *arg);
80
81 static inline int arch_unw_user_mode(const struct unwind_frame_info *info)
82 {
83 #if 0 /* This can only work when selector register and EFLAGS saves/restores
84          are properly annotated (and tracked in UNW_REGISTER_INFO). */
85         return user_mode_vm(&info->regs);
86 #else
87         return info->regs.eip < PAGE_OFFSET
88                || (info->regs.eip >= __fix_to_virt(FIX_VDSO)
89                     && info->regs.eip < __fix_to_virt(FIX_VDSO) + PAGE_SIZE)
90                || info->regs.esp < PAGE_OFFSET;
91 #endif
92 }
93
94 #else
95
96 #define UNW_PC(frame) ((void)(frame), 0)
97 #define UNW_SP(frame) ((void)(frame), 0)
98 #define UNW_FP(frame) ((void)(frame), 0)
99
100 static inline int arch_unw_user_mode(const void *info)
101 {
102         return 0;
103 }
104
105 #endif
106
107 #endif /* _ASM_I386_UNWIND_H */