[PATCH] vdso: randomize the i386 vDSO by moving it into a vma
[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 };
22
23 #define UNW_PC(frame)        (frame)->regs.eip
24 #define UNW_SP(frame)        (frame)->regs.esp
25 #ifdef CONFIG_FRAME_POINTER
26 #define UNW_FP(frame)        (frame)->regs.ebp
27 #define FRAME_RETADDR_OFFSET 4
28 #define FRAME_LINK_OFFSET    0
29 #define STACK_BOTTOM(tsk)    STACK_LIMIT((tsk)->thread.esp0)
30 #define STACK_TOP(tsk)       ((tsk)->thread.esp0)
31 #endif
32 #define STACK_LIMIT(ptr)     (((ptr) - 1) & ~(THREAD_SIZE - 1))
33
34 #define UNW_REGISTER_INFO \
35         PTREGS_INFO(eax), \
36         PTREGS_INFO(ecx), \
37         PTREGS_INFO(edx), \
38         PTREGS_INFO(ebx), \
39         PTREGS_INFO(esp), \
40         PTREGS_INFO(ebp), \
41         PTREGS_INFO(esi), \
42         PTREGS_INFO(edi), \
43         PTREGS_INFO(eip)
44
45 static inline void arch_unw_init_frame_info(struct unwind_frame_info *info,
46                                             /*const*/ struct pt_regs *regs)
47 {
48         if (user_mode_vm(regs))
49                 info->regs = *regs;
50         else {
51                 memcpy(&info->regs, regs, offsetof(struct pt_regs, esp));
52                 info->regs.esp = (unsigned long)&regs->esp;
53                 info->regs.xss = __KERNEL_DS;
54         }
55 }
56
57 static inline void arch_unw_init_blocked(struct unwind_frame_info *info)
58 {
59         memset(&info->regs, 0, sizeof(info->regs));
60         info->regs.eip = info->task->thread.eip;
61         info->regs.xcs = __KERNEL_CS;
62         __get_user(info->regs.ebp, (long *)info->task->thread.esp);
63         info->regs.esp = info->task->thread.esp;
64         info->regs.xss = __KERNEL_DS;
65         info->regs.xds = __USER_DS;
66         info->regs.xes = __USER_DS;
67 }
68
69 extern asmlinkage int arch_unwind_init_running(struct unwind_frame_info *,
70                                                asmlinkage int (*callback)(struct unwind_frame_info *,
71                                                                           void *arg),
72                                                void *arg);
73
74 static inline int arch_unw_user_mode(const struct unwind_frame_info *info)
75 {
76 #if 0 /* This can only work when selector register and EFLAGS saves/restores
77          are properly annotated (and tracked in UNW_REGISTER_INFO). */
78         return user_mode_vm(&info->regs);
79 #else
80         return info->regs.eip < PAGE_OFFSET
81                || (info->regs.eip >= __fix_to_virt(FIX_VDSO)
82                     && info->regs.eip < __fix_to_virt(FIX_VDSO) + PAGE_SIZE)
83                || info->regs.esp < PAGE_OFFSET;
84 #endif
85 }
86
87 #else
88
89 #define UNW_PC(frame) ((void)(frame), 0)
90
91 static inline int arch_unw_user_mode(const void *info)
92 {
93         return 0;
94 }
95
96 #endif
97
98 #endif /* _ASM_I386_UNWIND_H */