arch/alpha/include/asm/ptrace.h

   1 #ifndef _ASMAXP_PTRACE_H
   2 #define _ASMAXP_PTRACE_H
   3
   4
   5 /*
   6  * This struct defines the way the registers are stored on the
   7  * kernel stack during a system call or other kernel entry
   8  *
   9  * NOTE! I want to minimize the overhead of system calls, so this
  10  * struct has as little information as possible.  I does not have
  11  *
  12  *  - floating point regs: the kernel doesn't change those
  13  *  - r9-15: saved by the C compiler
  14  *
  15  * This makes "fork()" and "exec()" a bit more complex, but should
  16  * give us low system call latency.
  17  */
  18
  19 struct pt_regs {
  20         unsigned long r0;
  21         unsigned long r1;
  22         unsigned long r2;
  23         unsigned long r3;
  24         unsigned long r4;
  25         unsigned long r5;
  26         unsigned long r6;
  27         unsigned long r7;
  28         unsigned long r8;
  29         unsigned long r19;
  30         unsigned long r20;
  31         unsigned long r21;
  32         unsigned long r22;
  33         unsigned long r23;
  34         unsigned long r24;
  35         unsigned long r25;
  36         unsigned long r26;
  37         unsigned long r27;
  38         unsigned long r28;
  39         unsigned long hae;
  40 /* JRP - These are the values provided to a0-a2 by PALcode */
  41         unsigned long trap_a0;
  42         unsigned long trap_a1;
  43         unsigned long trap_a2;
  44 /* These are saved by PAL-code: */
  45         unsigned long ps;
  46         unsigned long pc;
  47         unsigned long gp;
  48         unsigned long r16;
  49         unsigned long r17;
  50         unsigned long r18;
  51 };
  52
  53 /*
  54  * This is the extended stack used by signal handlers and the context
  55  * switcher: it's pushed after the normal "struct pt_regs".
  56  */
  57 struct switch_stack {
  58         unsigned long r9;
  59         unsigned long r10;
  60         unsigned long r11;
  61         unsigned long r12;
  62         unsigned long r13;
  63         unsigned long r14;
  64         unsigned long r15;
  65         unsigned long r26;
  66         unsigned long fp[32];   /* fp[31] is fpcr */
  67 };
  68
  69 #ifdef __KERNEL__
  70
  71 #define arch_has_single_step()          (1)
  72 #define user_mode(regs) (((regs)->ps & 8) != 0)
  73 #define instruction_pointer(regs) ((regs)->pc)
  74 #define profile_pc(regs) instruction_pointer(regs)
  75
  76 #define task_pt_regs(task) \
  77   ((struct pt_regs *) (task_stack_page(task) + 2*PAGE_SIZE) - 1)
  78
  79 #define current_pt_regs() \
  80   ((struct pt_regs *) ((char *)current_thread_info() + 2*PAGE_SIZE) - 1)
  81 #define signal_pt_regs current_pt_regs
  82
  83 #define force_successful_syscall_return() (current_pt_regs()->r0 = 0)
  84
  85 #endif
  86
  87 #endif