1 #ifndef _ASM_X86_PTRACE_H
2 #define _ASM_X86_PTRACE_H
3
4 #include <asm/segment.h>
5 #include <asm/page_types.h>
6 #include <uapi/asm/ptrace.h>
7
8 #ifndef __ASSEMBLY__
9 #ifdef __i386__
10
11 struct pt_regs {
12 unsigned long bx;
13 unsigned long cx;
14 unsigned long dx;
15 unsigned long si;
16 unsigned long di;
17 unsigned long bp;
18 unsigned long ax;
19 unsigned long ds;
20 unsigned long es;
21 unsigned long fs;
22 unsigned long gs;
23 unsigned long orig_ax;
24 unsigned long ip;
25 unsigned long cs;
26 unsigned long flags;
27 unsigned long sp;
28 unsigned long ss;
29 };
30
31 #else /* __i386__ */
32
33 struct pt_regs {
34 /*
35 * C ABI says these regs are callee-preserved. They aren't saved on kernel entry
36 * unless syscall needs a complete, fully filled "struct pt_regs".
37 */
38 unsigned long r15;
39 unsigned long r14;
40 unsigned long r13;
41 unsigned long r12;
42 unsigned long bp;
43 unsigned long bx;
44 /* These regs are callee-clobbered. Always saved on kernel entry. */
45 unsigned long r11;
46 unsigned long r10;
47 unsigned long r9;
48 unsigned long r8;
49 unsigned long ax;
50 unsigned long cx;
51 unsigned long dx;
52 unsigned long si;
53 unsigned long di;
54 /*
55 * On syscall entry, this is syscall#. On CPU exception, this is error code.
56 * On hw interrupt, it's IRQ number:
57 */
58 unsigned long orig_ax;
59 /* Return frame for iretq */
60 unsigned long ip;
61 unsigned long cs;
62 unsigned long flags;
63 unsigned long sp;
64 unsigned long ss;
65 /* top of stack page */
66 };
67
68 #endif /* !__i386__ */
69
70 #ifdef CONFIG_PARAVIRT
71 #include <asm/paravirt_types.h>
72 #endif
73
74 struct cpuinfo_x86;
75 struct task_struct;
76
77 extern unsigned long profile_pc(struct pt_regs *regs);
78 #define profile_pc profile_pc
79
80 extern unsigned long
81 convert_ip_to_linear(struct task_struct *child, struct pt_regs *regs);
82 extern void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
83 int error_code, int si_code);
84
85
86 extern unsigned long syscall_trace_enter_phase1(struct pt_regs *, u32 arch);
87 extern long syscall_trace_enter_phase2(struct pt_regs *, u32 arch,
88 unsigned long phase1_result);
89
90 extern long syscall_trace_enter(struct pt_regs *);
91
regs_return_value(struct pt_regs * regs)92 static inline unsigned long regs_return_value(struct pt_regs *regs)
93 {
94 return regs->ax;
95 }
96
97 /*
98 * user_mode(regs) determines whether a register set came from user
99 * mode. On x86_32, this is true if V8086 mode was enabled OR if the
100 * register set was from protected mode with RPL-3 CS value. This
101 * tricky test checks that with one comparison.
102 *
103 * On x86_64, vm86 mode is mercifully nonexistent, and we don't need
104 * the extra check.
105 */
user_mode(struct pt_regs * regs)106 static inline int user_mode(struct pt_regs *regs)
107 {
108 #ifdef CONFIG_X86_32
109 return ((regs->cs & SEGMENT_RPL_MASK) | (regs->flags & X86_VM_MASK)) >= USER_RPL;
110 #else
111 return !!(regs->cs & 3);
112 #endif
113 }
114
v8086_mode(struct pt_regs * regs)115 static inline int v8086_mode(struct pt_regs *regs)
116 {
117 #ifdef CONFIG_X86_32
118 return (regs->flags & X86_VM_MASK);
119 #else
120 return 0; /* No V86 mode support in long mode */
121 #endif
122 }
123
user_64bit_mode(struct pt_regs * regs)124 static inline bool user_64bit_mode(struct pt_regs *regs)
125 {
126 #ifdef CONFIG_X86_64
127 #ifndef CONFIG_PARAVIRT
128 /*
129 * On non-paravirt systems, this is the only long mode CPL 3
130 * selector. We do not allow long mode selectors in the LDT.
131 */
132 return regs->cs == __USER_CS;
133 #else
134 /* Headers are too twisted for this to go in paravirt.h. */
135 return regs->cs == __USER_CS || regs->cs == pv_info.extra_user_64bit_cs;
136 #endif
137 #else /* !CONFIG_X86_64 */
138 return false;
139 #endif
140 }
141
142 #ifdef CONFIG_X86_64
143 #define current_user_stack_pointer() current_pt_regs()->sp
144 #define compat_user_stack_pointer() current_pt_regs()->sp
145 #endif
146
147 #ifdef CONFIG_X86_32
148 extern unsigned long kernel_stack_pointer(struct pt_regs *regs);
149 #else
kernel_stack_pointer(struct pt_regs * regs)150 static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
151 {
152 return regs->sp;
153 }
154 #endif
155
156 #define GET_IP(regs) ((regs)->ip)
157 #define GET_FP(regs) ((regs)->bp)
158 #define GET_USP(regs) ((regs)->sp)
159
160 #include <asm-generic/ptrace.h>
161
162 /* Query offset/name of register from its name/offset */
163 extern int regs_query_register_offset(const char *name);
164 extern const char *regs_query_register_name(unsigned int offset);
165 #define MAX_REG_OFFSET (offsetof(struct pt_regs, ss))
166
167 /**
168 * regs_get_register() - get register value from its offset
169 * @regs: pt_regs from which register value is gotten.
170 * @offset: offset number of the register.
171 *
172 * regs_get_register returns the value of a register. The @offset is the
173 * offset of the register in struct pt_regs address which specified by @regs.
174 * If @offset is bigger than MAX_REG_OFFSET, this returns 0.
175 */
regs_get_register(struct pt_regs * regs,unsigned int offset)176 static inline unsigned long regs_get_register(struct pt_regs *regs,
177 unsigned int offset)
178 {
179 if (unlikely(offset > MAX_REG_OFFSET))
180 return 0;
181 #ifdef CONFIG_X86_32
182 /*
183 * Traps from the kernel do not save sp and ss.
184 * Use the helper function to retrieve sp.
185 */
186 if (offset == offsetof(struct pt_regs, sp) &&
187 regs->cs == __KERNEL_CS)
188 return kernel_stack_pointer(regs);
189 #endif
190 return *(unsigned long *)((unsigned long)regs + offset);
191 }
192
193 /**
194 * regs_within_kernel_stack() - check the address in the stack
195 * @regs: pt_regs which contains kernel stack pointer.
196 * @addr: address which is checked.
197 *
198 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
199 * If @addr is within the kernel stack, it returns true. If not, returns false.
200 */
regs_within_kernel_stack(struct pt_regs * regs,unsigned long addr)201 static inline int regs_within_kernel_stack(struct pt_regs *regs,
202 unsigned long addr)
203 {
204 return ((addr & ~(THREAD_SIZE - 1)) ==
205 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)));
206 }
207
208 /**
209 * regs_get_kernel_stack_nth_addr() - get the address of the Nth entry on stack
210 * @regs: pt_regs which contains kernel stack pointer.
211 * @n: stack entry number.
212 *
213 * regs_get_kernel_stack_nth() returns the address of the @n th entry of the
214 * kernel stack which is specified by @regs. If the @n th entry is NOT in
215 * the kernel stack, this returns NULL.
216 */
regs_get_kernel_stack_nth_addr(struct pt_regs * regs,unsigned int n)217 static inline unsigned long *regs_get_kernel_stack_nth_addr(struct pt_regs *regs, unsigned int n)
218 {
219 unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
220
221 addr += n;
222 if (regs_within_kernel_stack(regs, (unsigned long)addr))
223 return addr;
224 else
225 return NULL;
226 }
227
228 /* To avoid include hell, we can't include uaccess.h */
229 extern long probe_kernel_read(void *dst, const void *src, size_t size);
230
231 /**
232 * regs_get_kernel_stack_nth() - get Nth entry of the stack
233 * @regs: pt_regs which contains kernel stack pointer.
234 * @n: stack entry number.
235 *
236 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
237 * is specified by @regs. If the @n th entry is NOT in the kernel stack
238 * this returns 0.
239 */
regs_get_kernel_stack_nth(struct pt_regs * regs,unsigned int n)240 static inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
241 unsigned int n)
242 {
243 unsigned long *addr;
244 unsigned long val;
245 long ret;
246
247 addr = regs_get_kernel_stack_nth_addr(regs, n);
248 if (addr) {
249 ret = probe_kernel_read(&val, addr, sizeof(val));
250 if (!ret)
251 return val;
252 }
253 return 0;
254 }
255
256 #define arch_has_single_step() (1)
257 #ifdef CONFIG_X86_DEBUGCTLMSR
258 #define arch_has_block_step() (1)
259 #else
260 #define arch_has_block_step() (boot_cpu_data.x86 >= 6)
261 #endif
262
263 #define ARCH_HAS_USER_SINGLE_STEP_INFO
264
265 /*
266 * When hitting ptrace_stop(), we cannot return using SYSRET because
267 * that does not restore the full CPU state, only a minimal set. The
268 * ptracer can change arbitrary register values, which is usually okay
269 * because the usual ptrace stops run off the signal delivery path which
270 * forces IRET; however, ptrace_event() stops happen in arbitrary places
271 * in the kernel and don't force IRET path.
272 *
273 * So force IRET path after a ptrace stop.
274 */
275 #define arch_ptrace_stop_needed(code, info) \
276 ({ \
277 force_iret(); \
278 false; \
279 })
280
281 struct user_desc;
282 extern int do_get_thread_area(struct task_struct *p, int idx,
283 struct user_desc __user *info);
284 extern int do_set_thread_area(struct task_struct *p, int idx,
285 struct user_desc __user *info, int can_allocate);
286
287 #endif /* !__ASSEMBLY__ */
288 #endif /* _ASM_X86_PTRACE_H */
289