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