1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * Copyright (C) 1998-2004 Hewlett-Packard Co
  4 *	David Mosberger-Tang <davidm@hpl.hp.com>
  5 *	Stephane Eranian <eranian@hpl.hp.com>
  6 * Copyright (C) 2003 Intel Co
  7 *	Suresh Siddha <suresh.b.siddha@intel.com>
  8 *	Fenghua Yu <fenghua.yu@intel.com>
  9 *	Arun Sharma <arun.sharma@intel.com>
 10 *
 11 * 12/07/98	S. Eranian	added pt_regs & switch_stack
 12 * 12/21/98	D. Mosberger	updated to match latest code
 13 *  6/17/99	D. Mosberger	added second unat member to "struct switch_stack"
 14 *
 15 */
 16#ifndef _ASM_IA64_PTRACE_H
 17#define _ASM_IA64_PTRACE_H
 18
 19#ifndef ASM_OFFSETS_C
 20#include <asm/asm-offsets.h>
 21#endif
 22#include <uapi/asm/ptrace.h>
 23
 24/*
 25 * Base-2 logarithm of number of pages to allocate per task structure
 26 * (including register backing store and memory stack):
 27 */
 28#if defined(CONFIG_IA64_PAGE_SIZE_4KB)
 29# define KERNEL_STACK_SIZE_ORDER		3
 30#elif defined(CONFIG_IA64_PAGE_SIZE_8KB)
 31# define KERNEL_STACK_SIZE_ORDER		2
 32#elif defined(CONFIG_IA64_PAGE_SIZE_16KB)
 33# define KERNEL_STACK_SIZE_ORDER		1
 34#else
 35# define KERNEL_STACK_SIZE_ORDER		0
 36#endif
 37
 38#define IA64_RBS_OFFSET			((IA64_TASK_SIZE + IA64_THREAD_INFO_SIZE + 31) & ~31)
 39#define IA64_STK_OFFSET			((1 << KERNEL_STACK_SIZE_ORDER)*PAGE_SIZE)
 40
 41#define KERNEL_STACK_SIZE		IA64_STK_OFFSET
 42
 43#ifndef __ASSEMBLY__
 44
 45#include <asm/current.h>
 46#include <asm/page.h>
 47
 48/*
 49 * We use the ia64_psr(regs)->ri to determine which of the three
 50 * instructions in bundle (16 bytes) took the sample. Generate
 51 * the canonical representation by adding to instruction pointer.
 52 */
 53# define instruction_pointer(regs) ((regs)->cr_iip + ia64_psr(regs)->ri)
 54
 55static inline unsigned long user_stack_pointer(struct pt_regs *regs)
 56{
 57	/* FIXME: should this be bspstore + nr_dirty regs? */
 58	return regs->ar_bspstore;
 59}
 60
 61static inline int is_syscall_success(struct pt_regs *regs)
 62{
 63	return regs->r10 != -1;
 64}
 65
 66static inline long regs_return_value(struct pt_regs *regs)
 67{
 68	if (is_syscall_success(regs))
 69		return regs->r8;
 70	else
 71		return -regs->r8;
 72}
 73
 74/* Conserve space in histogram by encoding slot bits in address
 75 * bits 2 and 3 rather than bits 0 and 1.
 76 */
 77#define profile_pc(regs)						\
 78({									\
 79	unsigned long __ip = instruction_pointer(regs);			\
 80	(__ip & ~3UL) + ((__ip & 3UL) << 2);				\
 81})
 82/*
 83 * Why not default?  Because user_stack_pointer() on ia64 gives register
 84 * stack backing store instead...
 85 */
 86#define current_user_stack_pointer() (current_pt_regs()->r12)
 87
 88  /* given a pointer to a task_struct, return the user's pt_regs */
 89# define task_pt_regs(t)		(((struct pt_regs *) ((char *) (t) + IA64_STK_OFFSET)) - 1)
 90# define ia64_psr(regs)			((struct ia64_psr *) &(regs)->cr_ipsr)
 91# define user_mode(regs)		(((struct ia64_psr *) &(regs)->cr_ipsr)->cpl != 0)
 92# define user_stack(task,regs)	((long) regs - (long) task == IA64_STK_OFFSET - sizeof(*regs))
 93# define fsys_mode(task,regs)					\
 94  ({								\
 95	  struct task_struct *_task = (task);			\
 96	  struct pt_regs *_regs = (regs);			\
 97	  !user_mode(_regs) && user_stack(_task, _regs);	\
 98  })
 99
100  /*
101   * System call handlers that, upon successful completion, need to return a negative value
102   * should call force_successful_syscall_return() right before returning.  On architectures
103   * where the syscall convention provides for a separate error flag (e.g., alpha, ia64,
104   * ppc{,64}, sparc{,64}, possibly others), this macro can be used to ensure that the error
105   * flag will not get set.  On architectures which do not support a separate error flag,
106   * the macro is a no-op and the spurious error condition needs to be filtered out by some
107   * other means (e.g., in user-level, by passing an extra argument to the syscall handler,
108   * or something along those lines).
109   *
110   * On ia64, we can clear the user's pt_regs->r8 to force a successful syscall.
111   */
112# define force_successful_syscall_return()	(task_pt_regs(current)->r8 = 0)
113
114  struct task_struct;			/* forward decl */
115  struct unw_frame_info;		/* forward decl */
116
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 */