xref: /openbmc/linux/arch/ia64/include/asm/ptrace.h (revision 293d5b43)
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 */
152