include/asm-x86_64/unwind.h

   1 #ifndef _ASM_X86_64_UNWIND_H
   2 #define _ASM_X86_64_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/ptrace.h>
  14 #include <asm/uaccess.h>
  15 #include <asm/vsyscall.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.rip
  25 #define UNW_SP(frame)        (frame)->regs.rsp
  26 #ifdef CONFIG_FRAME_POINTER
  27 #define UNW_FP(frame)        (frame)->regs.rbp
  28 #define FRAME_RETADDR_OFFSET 8
  29 #define FRAME_LINK_OFFSET    0
  30 #define STACK_BOTTOM(tsk)    (((tsk)->thread.rsp0 - 1) & ~(THREAD_SIZE - 1))
  31 #define STACK_TOP(tsk)       ((tsk)->thread.rsp0)
  32 #endif
  33 /* Might need to account for the special exception and interrupt handling
  34    stacks here, since normally
  35         EXCEPTION_STACK_ORDER < THREAD_ORDER < IRQSTACK_ORDER,
  36    but the construct is needed only for getting across the stack switch to
  37    the interrupt stack - thus considering the IRQ stack itself is unnecessary,
  38    and the overhead of comparing against all exception handling stacks seems
  39    not desirable. */
  40 #define STACK_LIMIT(ptr)     (((ptr) - 1) & ~(THREAD_SIZE - 1))
  41
  42 #define UNW_REGISTER_INFO \
  43         PTREGS_INFO(rax), \
  44         PTREGS_INFO(rdx), \
  45         PTREGS_INFO(rcx), \
  46         PTREGS_INFO(rbx), \
  47         PTREGS_INFO(rsi), \
  48         PTREGS_INFO(rdi), \
  49         PTREGS_INFO(rbp), \
  50         PTREGS_INFO(rsp), \
  51         PTREGS_INFO(r8), \
  52         PTREGS_INFO(r9), \
  53         PTREGS_INFO(r10), \
  54         PTREGS_INFO(r11), \
  55         PTREGS_INFO(r12), \
  56         PTREGS_INFO(r13), \
  57         PTREGS_INFO(r14), \
  58         PTREGS_INFO(r15), \
  59         PTREGS_INFO(rip)
  60
  61 #define UNW_DEFAULT_RA(raItem, dataAlign) \
  62         ((raItem).where == Memory && \
  63          !((raItem).value * (dataAlign) + 8))
  64
  65 static inline void arch_unw_init_frame_info(struct unwind_frame_info *info,
  66                                             /*const*/ struct pt_regs *regs)
  67 {
  68         info->regs = *regs;
  69 }
  70
  71 static inline void arch_unw_init_blocked(struct unwind_frame_info *info)
  72 {
  73         extern const char thread_return[];
  74
  75         memset(&info->regs, 0, sizeof(info->regs));
  76         info->regs.rip = (unsigned long)thread_return;
  77         info->regs.cs = __KERNEL_CS;
  78         __get_user(info->regs.rbp, (unsigned long *)info->task->thread.rsp);
  79         info->regs.rsp = info->task->thread.rsp;
  80         info->regs.ss = __KERNEL_DS;
  81 }
  82
  83 extern int arch_unwind_init_running(struct unwind_frame_info *,
  84                                     int (*callback)(struct unwind_frame_info *,
  85                                                     void *arg),
  86                                     void *arg);
  87
  88 static inline int arch_unw_user_mode(const struct unwind_frame_info *info)
  89 {
  90 #if 0 /* This can only work when selector register saves/restores
  91          are properly annotated (and tracked in UNW_REGISTER_INFO). */
  92         return user_mode(&info->regs);
  93 #else
  94         return (long)info->regs.rip >= 0
  95                || (info->regs.rip >= VSYSCALL_START && info->regs.rip < VSYSCALL_END)
  96                || (long)info->regs.rsp >= 0;
  97 #endif
  98 }
  99
 100 #else
 101
 102 #define UNW_PC(frame) ((void)(frame), 0UL)
 103 #define UNW_SP(frame) ((void)(frame), 0UL)
 104
 105 static inline int arch_unw_user_mode(const void *info)
 106 {
 107         return 0;
 108 }
 109
 110 #endif
 111
 112 #endif /* _ASM_X86_64_UNWIND_H */