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
  54 static 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
  60 static inline int is_syscall_success(struct pt_regs *regs)
  61 {
  62         return regs->r10 != -1;
  63 }
  64
  65 static 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 */