xref: /openbmc/linux/arch/x86/include/asm/ptrace.h (revision a09d2831)
1 #ifndef _ASM_X86_PTRACE_H
2 #define _ASM_X86_PTRACE_H
3 
4 #include <linux/compiler.h>	/* For __user */
5 #include <asm/ptrace-abi.h>
6 #include <asm/processor-flags.h>
7 
8 #ifdef __KERNEL__
9 #include <asm/segment.h>
10 #include <asm/page_types.h>
11 #endif
12 
13 #ifndef __ASSEMBLY__
14 
15 #ifdef __i386__
16 /* this struct defines the way the registers are stored on the
17    stack during a system call. */
18 
19 #ifndef __KERNEL__
20 
21 struct pt_regs {
22 	long ebx;
23 	long ecx;
24 	long edx;
25 	long esi;
26 	long edi;
27 	long ebp;
28 	long eax;
29 	int  xds;
30 	int  xes;
31 	int  xfs;
32 	int  xgs;
33 	long orig_eax;
34 	long eip;
35 	int  xcs;
36 	long eflags;
37 	long esp;
38 	int  xss;
39 };
40 
41 #else /* __KERNEL__ */
42 
43 struct pt_regs {
44 	unsigned long bx;
45 	unsigned long cx;
46 	unsigned long dx;
47 	unsigned long si;
48 	unsigned long di;
49 	unsigned long bp;
50 	unsigned long ax;
51 	unsigned long ds;
52 	unsigned long es;
53 	unsigned long fs;
54 	unsigned long gs;
55 	unsigned long orig_ax;
56 	unsigned long ip;
57 	unsigned long cs;
58 	unsigned long flags;
59 	unsigned long sp;
60 	unsigned long ss;
61 };
62 
63 #endif /* __KERNEL__ */
64 
65 #else /* __i386__ */
66 
67 #ifndef __KERNEL__
68 
69 struct pt_regs {
70 	unsigned long r15;
71 	unsigned long r14;
72 	unsigned long r13;
73 	unsigned long r12;
74 	unsigned long rbp;
75 	unsigned long rbx;
76 /* arguments: non interrupts/non tracing syscalls only save upto here*/
77 	unsigned long r11;
78 	unsigned long r10;
79 	unsigned long r9;
80 	unsigned long r8;
81 	unsigned long rax;
82 	unsigned long rcx;
83 	unsigned long rdx;
84 	unsigned long rsi;
85 	unsigned long rdi;
86 	unsigned long orig_rax;
87 /* end of arguments */
88 /* cpu exception frame or undefined */
89 	unsigned long rip;
90 	unsigned long cs;
91 	unsigned long eflags;
92 	unsigned long rsp;
93 	unsigned long ss;
94 /* top of stack page */
95 };
96 
97 #else /* __KERNEL__ */
98 
99 struct pt_regs {
100 	unsigned long r15;
101 	unsigned long r14;
102 	unsigned long r13;
103 	unsigned long r12;
104 	unsigned long bp;
105 	unsigned long bx;
106 /* arguments: non interrupts/non tracing syscalls only save upto here*/
107 	unsigned long r11;
108 	unsigned long r10;
109 	unsigned long r9;
110 	unsigned long r8;
111 	unsigned long ax;
112 	unsigned long cx;
113 	unsigned long dx;
114 	unsigned long si;
115 	unsigned long di;
116 	unsigned long orig_ax;
117 /* end of arguments */
118 /* cpu exception frame or undefined */
119 	unsigned long ip;
120 	unsigned long cs;
121 	unsigned long flags;
122 	unsigned long sp;
123 	unsigned long ss;
124 /* top of stack page */
125 };
126 
127 #endif /* __KERNEL__ */
128 #endif /* !__i386__ */
129 
130 
131 #ifdef __KERNEL__
132 
133 #include <linux/init.h>
134 
135 struct cpuinfo_x86;
136 struct task_struct;
137 
138 extern unsigned long profile_pc(struct pt_regs *regs);
139 
140 extern unsigned long
141 convert_ip_to_linear(struct task_struct *child, struct pt_regs *regs);
142 extern void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
143 			 int error_code, int si_code);
144 void signal_fault(struct pt_regs *regs, void __user *frame, char *where);
145 
146 extern long syscall_trace_enter(struct pt_regs *);
147 extern void syscall_trace_leave(struct pt_regs *);
148 
149 static inline unsigned long regs_return_value(struct pt_regs *regs)
150 {
151 	return regs->ax;
152 }
153 
154 /*
155  * user_mode_vm(regs) determines whether a register set came from user mode.
156  * This is true if V8086 mode was enabled OR if the register set was from
157  * protected mode with RPL-3 CS value.  This tricky test checks that with
158  * one comparison.  Many places in the kernel can bypass this full check
159  * if they have already ruled out V8086 mode, so user_mode(regs) can be used.
160  */
161 static inline int user_mode(struct pt_regs *regs)
162 {
163 #ifdef CONFIG_X86_32
164 	return (regs->cs & SEGMENT_RPL_MASK) == USER_RPL;
165 #else
166 	return !!(regs->cs & 3);
167 #endif
168 }
169 
170 static inline int user_mode_vm(struct pt_regs *regs)
171 {
172 #ifdef CONFIG_X86_32
173 	return ((regs->cs & SEGMENT_RPL_MASK) | (regs->flags & X86_VM_MASK)) >=
174 		USER_RPL;
175 #else
176 	return user_mode(regs);
177 #endif
178 }
179 
180 static inline int v8086_mode(struct pt_regs *regs)
181 {
182 #ifdef CONFIG_X86_32
183 	return (regs->flags & X86_VM_MASK);
184 #else
185 	return 0;	/* No V86 mode support in long mode */
186 #endif
187 }
188 
189 /*
190  * X86_32 CPUs don't save ss and esp if the CPU is already in kernel mode
191  * when it traps.  The previous stack will be directly underneath the saved
192  * registers, and 'sp/ss' won't even have been saved. Thus the '&regs->sp'.
193  *
194  * This is valid only for kernel mode traps.
195  */
196 static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
197 {
198 #ifdef CONFIG_X86_32
199 	return (unsigned long)(&regs->sp);
200 #else
201 	return regs->sp;
202 #endif
203 }
204 
205 static inline unsigned long instruction_pointer(struct pt_regs *regs)
206 {
207 	return regs->ip;
208 }
209 
210 static inline unsigned long frame_pointer(struct pt_regs *regs)
211 {
212 	return regs->bp;
213 }
214 
215 static inline unsigned long user_stack_pointer(struct pt_regs *regs)
216 {
217 	return regs->sp;
218 }
219 
220 /* Query offset/name of register from its name/offset */
221 extern int regs_query_register_offset(const char *name);
222 extern const char *regs_query_register_name(unsigned int offset);
223 #define MAX_REG_OFFSET (offsetof(struct pt_regs, ss))
224 
225 /**
226  * regs_get_register() - get register value from its offset
227  * @regs:	pt_regs from which register value is gotten.
228  * @offset:	offset number of the register.
229  *
230  * regs_get_register returns the value of a register. The @offset is the
231  * offset of the register in struct pt_regs address which specified by @regs.
232  * If @offset is bigger than MAX_REG_OFFSET, this returns 0.
233  */
234 static inline unsigned long regs_get_register(struct pt_regs *regs,
235 					      unsigned int offset)
236 {
237 	if (unlikely(offset > MAX_REG_OFFSET))
238 		return 0;
239 	return *(unsigned long *)((unsigned long)regs + offset);
240 }
241 
242 /**
243  * regs_within_kernel_stack() - check the address in the stack
244  * @regs:	pt_regs which contains kernel stack pointer.
245  * @addr:	address which is checked.
246  *
247  * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
248  * If @addr is within the kernel stack, it returns true. If not, returns false.
249  */
250 static inline int regs_within_kernel_stack(struct pt_regs *regs,
251 					   unsigned long addr)
252 {
253 	return ((addr & ~(THREAD_SIZE - 1))  ==
254 		(kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)));
255 }
256 
257 /**
258  * regs_get_kernel_stack_nth() - get Nth entry of the stack
259  * @regs:	pt_regs which contains kernel stack pointer.
260  * @n:		stack entry number.
261  *
262  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
263  * is specified by @regs. If the @n th entry is NOT in the kernel stack,
264  * this returns 0.
265  */
266 static inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
267 						      unsigned int n)
268 {
269 	unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
270 	addr += n;
271 	if (regs_within_kernel_stack(regs, (unsigned long)addr))
272 		return *addr;
273 	else
274 		return 0;
275 }
276 
277 /* Get Nth argument at function call */
278 extern unsigned long regs_get_argument_nth(struct pt_regs *regs,
279 					   unsigned int n);
280 
281 /*
282  * These are defined as per linux/ptrace.h, which see.
283  */
284 #define arch_has_single_step()	(1)
285 extern void user_enable_single_step(struct task_struct *);
286 extern void user_disable_single_step(struct task_struct *);
287 
288 extern void user_enable_block_step(struct task_struct *);
289 #ifdef CONFIG_X86_DEBUGCTLMSR
290 #define arch_has_block_step()	(1)
291 #else
292 #define arch_has_block_step()	(boot_cpu_data.x86 >= 6)
293 #endif
294 
295 #define ARCH_HAS_USER_SINGLE_STEP_INFO
296 
297 struct user_desc;
298 extern int do_get_thread_area(struct task_struct *p, int idx,
299 			      struct user_desc __user *info);
300 extern int do_set_thread_area(struct task_struct *p, int idx,
301 			      struct user_desc __user *info, int can_allocate);
302 
303 #ifdef CONFIG_X86_PTRACE_BTS
304 extern void ptrace_bts_untrace(struct task_struct *tsk);
305 
306 #define arch_ptrace_untrace(tsk)	ptrace_bts_untrace(tsk)
307 #endif /* CONFIG_X86_PTRACE_BTS */
308 
309 #endif /* __KERNEL__ */
310 
311 #endif /* !__ASSEMBLY__ */
312 
313 #endif /* _ASM_X86_PTRACE_H */
314