arch/x86/include/asm/ptrace.h

   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 up to 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 up to 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 #ifdef CONFIG_PARAVIRT
 135 #include <asm/paravirt_types.h>
 136 #endif
 137
 138 struct cpuinfo_x86;
 139 struct task_struct;
 140
 141 extern unsigned long profile_pc(struct pt_regs *regs);
 142 #define profile_pc profile_pc
 143
 144 extern unsigned long
 145 convert_ip_to_linear(struct task_struct *child, struct pt_regs *regs);
 146 extern void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
 147                          int error_code, int si_code);
 148 void signal_fault(struct pt_regs *regs, void __user *frame, char *where);
 149
 150 extern long syscall_trace_enter(struct pt_regs *);
 151 extern void syscall_trace_leave(struct pt_regs *);
 152
 153 static inline unsigned long regs_return_value(struct pt_regs *regs)
 154 {
 155         return regs->ax;
 156 }
 157
 158 /*
 159  * user_mode_vm(regs) determines whether a register set came from user mode.
 160  * This is true if V8086 mode was enabled OR if the register set was from
 161  * protected mode with RPL-3 CS value.  This tricky test checks that with
 162  * one comparison.  Many places in the kernel can bypass this full check
 163  * if they have already ruled out V8086 mode, so user_mode(regs) can be used.
 164  */
 165 static inline int user_mode(struct pt_regs *regs)
 166 {
 167 #ifdef CONFIG_X86_32
 168         return (regs->cs & SEGMENT_RPL_MASK) == USER_RPL;
 169 #else
 170         return !!(regs->cs & 3);
 171 #endif
 172 }
 173
 174 static inline int user_mode_vm(struct pt_regs *regs)
 175 {
 176 #ifdef CONFIG_X86_32
 177         return ((regs->cs & SEGMENT_RPL_MASK) | (regs->flags & X86_VM_MASK)) >=
 178                 USER_RPL;
 179 #else
 180         return user_mode(regs);
 181 #endif
 182 }
 183
 184 static inline int v8086_mode(struct pt_regs *regs)
 185 {
 186 #ifdef CONFIG_X86_32
 187         return (regs->flags & X86_VM_MASK);
 188 #else
 189         return 0;       /* No V86 mode support in long mode */
 190 #endif
 191 }
 192
 193 #ifdef CONFIG_X86_64
 194 static inline bool user_64bit_mode(struct pt_regs *regs)
 195 {
 196 #ifndef CONFIG_PARAVIRT
 197         /*
 198          * On non-paravirt systems, this is the only long mode CPL 3
 199          * selector.  We do not allow long mode selectors in the LDT.
 200          */
 201         return regs->cs == __USER_CS;
 202 #else
 203         /* Headers are too twisted for this to go in paravirt.h. */
 204         return regs->cs == __USER_CS || regs->cs == pv_info.extra_user_64bit_cs;
 205 #endif
 206 }
 207 #endif
 208
 209 /*
 210  * X86_32 CPUs don't save ss and esp if the CPU is already in kernel mode
 211  * when it traps.  The previous stack will be directly underneath the saved
 212  * registers, and 'sp/ss' won't even have been saved. Thus the '&regs->sp'.
 213  *
 214  * This is valid only for kernel mode traps.
 215  */
 216 static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
 217 {
 218 #ifdef CONFIG_X86_32
 219         return (unsigned long)(&regs->sp);
 220 #else
 221         return regs->sp;
 222 #endif
 223 }
 224
 225 #define GET_IP(regs) ((regs)->ip)
 226 #define GET_FP(regs) ((regs)->bp)
 227 #define GET_USP(regs) ((regs)->sp)
 228
 229 #include <asm-generic/ptrace.h>
 230
 231 /* Query offset/name of register from its name/offset */
 232 extern int regs_query_register_offset(const char *name);
 233 extern const char *regs_query_register_name(unsigned int offset);
 234 #define MAX_REG_OFFSET (offsetof(struct pt_regs, ss))
 235
 236 /**
 237  * regs_get_register() - get register value from its offset
 238  * @regs:       pt_regs from which register value is gotten.
 239  * @offset:     offset number of the register.
 240  *
 241  * regs_get_register returns the value of a register. The @offset is the
 242  * offset of the register in struct pt_regs address which specified by @regs.
 243  * If @offset is bigger than MAX_REG_OFFSET, this returns 0.
 244  */
 245 static inline unsigned long regs_get_register(struct pt_regs *regs,
 246                                               unsigned int offset)
 247 {
 248         if (unlikely(offset > MAX_REG_OFFSET))
 249                 return 0;
 250         return *(unsigned long *)((unsigned long)regs + offset);
 251 }
 252
 253 /**
 254  * regs_within_kernel_stack() - check the address in the stack
 255  * @regs:       pt_regs which contains kernel stack pointer.
 256  * @addr:       address which is checked.
 257  *
 258  * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
 259  * If @addr is within the kernel stack, it returns true. If not, returns false.
 260  */
 261 static inline int regs_within_kernel_stack(struct pt_regs *regs,
 262                                            unsigned long addr)
 263 {
 264         return ((addr & ~(THREAD_SIZE - 1))  ==
 265                 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)));
 266 }
 267
 268 /**
 269  * regs_get_kernel_stack_nth() - get Nth entry of the stack
 270  * @regs:       pt_regs which contains kernel stack pointer.
 271  * @n:          stack entry number.
 272  *
 273  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
 274  * is specified by @regs. If the @n th entry is NOT in the kernel stack,
 275  * this returns 0.
 276  */
 277 static inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
 278                                                       unsigned int n)
 279 {
 280         unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
 281         addr += n;
 282         if (regs_within_kernel_stack(regs, (unsigned long)addr))
 283                 return *addr;
 284         else
 285                 return 0;
 286 }
 287
 288 #define arch_has_single_step()  (1)
 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 #endif /* __KERNEL__ */
 304
 305 #endif /* !__ASSEMBLY__ */
 306
 307 #endif /* _ASM_X86_PTRACE_H */