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 */