LXR linux/arch/ia64/include/asm/ptrace.h

   1/*
   2 * Copyright (C) 1998-2004 Hewlett-Packard Co
   3 *      David Mosberger-Tang <davidm@hpl.hp.com>
   4 *      Stephane Eranian <eranian@hpl.hp.com>
   5 * Copyright (C) 2003 Intel Co
   6 *      Suresh Siddha <suresh.b.siddha@intel.com>
   7 *      Fenghua Yu <fenghua.yu@intel.com>
   8 *      Arun Sharma <arun.sharma@intel.com>
   9 *
  10 * 12/07/98     S. Eranian      added pt_regs & switch_stack
  11 * 12/21/98     D. Mosberger    updated to match latest code
  12 *  6/17/99     D. Mosberger    added second unat member to "struct switch_stack"
  13 *
  14 */
  15#ifndef _ASM_IA64_PTRACE_H
  16#define _ASM_IA64_PTRACE_H
  17
  18#ifndef ASM_OFFSETS_C
  19#include <asm/asm-offsets.h>
  20#endif
  21#include <uapi/asm/ptrace.h>
  22
  23/*
  24 * Base-2 logarithm of number of pages to allocate per task structure
  25 * (including register backing store and memory stack):
  26 */
  27#if defined(CONFIG_IA64_PAGE_SIZE_4KB)
  28# define KERNEL_STACK_SIZE_ORDER                3
  29#elif defined(CONFIG_IA64_PAGE_SIZE_8KB)
  30# define KERNEL_STACK_SIZE_ORDER                2
  31#elif defined(CONFIG_IA64_PAGE_SIZE_16KB)
  32# define KERNEL_STACK_SIZE_ORDER                1
  33#else
  34# define KERNEL_STACK_SIZE_ORDER                0
  35#endif
  36
  37#define IA64_RBS_OFFSET                 ((IA64_TASK_SIZE + IA64_THREAD_INFO_SIZE + 31) & ~31)
  38#define IA64_STK_OFFSET                 ((1 << KERNEL_STACK_SIZE_ORDER)*PAGE_SIZE)
  39
  40#define KERNEL_STACK_SIZE               IA64_STK_OFFSET
  41
  42#ifndef __ASSEMBLY__
  43
  44#include <asm/current.h>
  45#include <asm/page.h>
  46
  47/*
  48 * We use the ia64_psr(regs)->ri to determine which of the three
  49 * instructions in bundle (16 bytes) took the sample. Generate
  50 * the canonical representation by adding to instruction pointer.
  51 */
  52# define instruction_pointer(regs) ((regs)->cr_iip + ia64_psr(regs)->ri)
  53
  54static inline unsigned long user_stack_pointer(struct pt_regs *regs)
  55{
  56        /* FIXME: should this be bspstore + nr_dirty regs? */
  57        return regs->ar_bspstore;
  58}
  59
  60static inline int is_syscall_success(struct pt_regs *regs)
  61{
  62        return regs->r10 != -1;
  63}
  64
  65static inline long regs_return_value(struct pt_regs *regs)
  66{
  67        if (is_syscall_success(regs))
  68                return regs->r8;
  69        else
  70                return -regs->r8;
  71}
  72
  73/* Conserve space in histogram by encoding slot bits in address
  74 * bits 2 and 3 rather than bits 0 and 1.
  75 */
  76#define profile_pc(regs)                                                \
  77({                                                                      \
  78        unsigned long __ip = instruction_pointer(regs);                 \
  79        (__ip & ~3UL) + ((__ip & 3UL) << 2);                            \
  80})
  81/*
  82 * Why not default?  Because user_stack_pointer() on ia64 gives register
  83 * stack backing store instead...
  84 */
  85#define current_user_stack_pointer() (current_pt_regs()->r12)
  86
  87  /* given a pointer to a task_struct, return the user's pt_regs */
  88# define task_pt_regs(t)                (((struct pt_regs *) ((char *) (t) + IA64_STK_OFFSET)) - 1)
  89# define ia64_psr(regs)                 ((struct ia64_psr *) &(regs)->cr_ipsr)
  90# define user_mode(regs)                (((struct ia64_psr *) &(regs)->cr_ipsr)->cpl != 0)
  91# define user_stack(task,regs)  ((long) regs - (long) task == IA64_STK_OFFSET - sizeof(*regs))
  92# define fsys_mode(task,regs)                                   \
  93  ({                                                            \
  94          struct task_struct *_task = (task);                   \
  95          struct pt_regs *_regs = (regs);                       \
  96          !user_mode(_regs) && user_stack(_task, _regs);        \
  97  })
  98
  99  /*
 100   * System call handlers that, upon successful completion, need to return a negative value
 101   * should call force_successful_syscall_return() right before returning.  On architectures
 102   * where the syscall convention provides for a separate error flag (e.g., alpha, ia64,
 103   * ppc{,64}, sparc{,64}, possibly others), this macro can be used to ensure that the error
 104   * flag will not get set.  On architectures which do not support a separate error flag,
 105   * the macro is a no-op and the spurious error condition needs to be filtered out by some
 106   * other means (e.g., in user-level, by passing an extra argument to the syscall handler,
 107   * or something along those lines).
 108   *
 109   * On ia64, we can clear the user's pt_regs->r8 to force a successful syscall.
 110   */
 111# define force_successful_syscall_return()      (task_pt_regs(current)->r8 = 0)
 112
 113  struct task_struct;                   /* forward decl */
 114  struct unw_frame_info;                /* forward decl */
 115
 116  extern void ia64_do_show_stack (struct unw_frame_info *, void *);
 117  extern unsigned long ia64_get_user_rbs_end (struct task_struct *, struct pt_regs *,
 118                                              unsigned long *);
 119  extern long ia64_peek (struct task_struct *, struct switch_stack *, unsigned long,
 120                         unsigned long, long *);
 121  extern long ia64_poke (struct task_struct *, struct switch_stack *, unsigned long,
 122                         unsigned long, long);
 123  extern void ia64_flush_fph (struct task_struct *);
 124  extern void ia64_sync_fph (struct task_struct *);
 125  extern void ia64_sync_krbs(void);
 126  extern long ia64_sync_user_rbs (struct task_struct *, struct switch_stack *,
 127                                  unsigned long, unsigned long);
 128
 129  /* get nat bits for scratch registers such that bit N==1 iff scratch register rN is a NaT */
 130  extern unsigned long ia64_get_scratch_nat_bits (struct pt_regs *pt, unsigned long scratch_unat);
 131  /* put nat bits for scratch registers such that scratch register rN is a NaT iff bit N==1 */
 132  extern unsigned long ia64_put_scratch_nat_bits (struct pt_regs *pt, unsigned long nat);
 133
 134  extern void ia64_increment_ip (struct pt_regs *pt);
 135  extern void ia64_decrement_ip (struct pt_regs *pt);
 136
 137  extern void ia64_ptrace_stop(void);
 138  #define arch_ptrace_stop(code, info) \
 139        ia64_ptrace_stop()
 140  #define arch_ptrace_stop_needed(code, info) \
 141        (!test_thread_flag(TIF_RESTORE_RSE))
 142
 143  extern void ptrace_attach_sync_user_rbs (struct task_struct *);
 144  #define arch_ptrace_attach(child) \
 145        ptrace_attach_sync_user_rbs(child)
 146
 147  #define arch_has_single_step()  (1)
 148  #define arch_has_block_step()   (1)
 149
 150#endif /* !__ASSEMBLY__ */
 151#endif /* _ASM_IA64_PTRACE_H */
 152