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#ifndef _ASM_X86_PTRACE_H
#define _ASM_X86_PTRACE_H
#include <linux/compiler.h> /* For __user */
#include <asm/ptrace-abi.h>
#include <asm/processor-flags.h>
#ifdef __KERNEL__
#include <asm/segment.h>
#include <asm/page_types.h>
#endif
#ifndef __ASSEMBLY__
#ifdef __i386__
/* this struct defines the way the registers are stored on the
stack during a system call. */
#ifndef __KERNEL__
struct pt_regs {
long ebx;
long ecx;
long edx;
long esi;
long edi;
long ebp;
long eax;
int xds;
int xes;
int xfs;
int xgs;
long orig_eax;
long eip;
int xcs;
long eflags;
long esp;
int xss;
};
#else /* __KERNEL__ */
struct pt_regs {
unsigned long bx;
unsigned long cx;
unsigned long dx;
unsigned long si;
unsigned long di;
unsigned long bp;
unsigned long ax;
unsigned long ds;
unsigned long es;
unsigned long fs;
unsigned long gs;
unsigned long orig_ax;
unsigned long ip;
unsigned long cs;
unsigned long flags;
unsigned long sp;
unsigned long ss;
};
#endif /* __KERNEL__ */
#else /* __i386__ */
#ifndef __KERNEL__
struct pt_regs {
unsigned long r15;
unsigned long r14;
unsigned long r13;
unsigned long r12;
unsigned long rbp;
unsigned long rbx;
/* arguments: non interrupts/non tracing syscalls only save upto here*/
unsigned long r11;
unsigned long r10;
unsigned long r9;
unsigned long r8;
unsigned long rax;
unsigned long rcx;
unsigned long rdx;
unsigned long rsi;
unsigned long rdi;
unsigned long orig_rax;
/* end of arguments */
/* cpu exception frame or undefined */
unsigned long rip;
unsigned long cs;
unsigned long eflags;
unsigned long rsp;
unsigned long ss;
/* top of stack page */
};
#else /* __KERNEL__ */
struct pt_regs {
unsigned long r15;
unsigned long r14;
unsigned long r13;
unsigned long r12;
unsigned long bp;
unsigned long bx;
/* arguments: non interrupts/non tracing syscalls only save upto here*/
unsigned long r11;
unsigned long r10;
unsigned long r9;
unsigned long r8;
unsigned long ax;
unsigned long cx;
unsigned long dx;
unsigned long si;
unsigned long di;
unsigned long orig_ax;
/* end of arguments */
/* cpu exception frame or undefined */
unsigned long ip;
unsigned long cs;
unsigned long flags;
unsigned long sp;
unsigned long ss;
/* top of stack page */
};
#endif /* __KERNEL__ */
#endif /* !__i386__ */
#ifdef __KERNEL__
#include <linux/init.h>
struct cpuinfo_x86;
struct task_struct;
extern unsigned long profile_pc(struct pt_regs *regs);
extern unsigned long
convert_ip_to_linear(struct task_struct *child, struct pt_regs *regs);
extern void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
int error_code, int si_code);
void signal_fault(struct pt_regs *regs, void __user *frame, char *where);
extern long syscall_trace_enter(struct pt_regs *);
extern void syscall_trace_leave(struct pt_regs *);
static inline unsigned long regs_return_value(struct pt_regs *regs)
{
return regs->ax;
}
/*
* user_mode_vm(regs) determines whether a register set came from user mode.
* This is true if V8086 mode was enabled OR if the register set was from
* protected mode with RPL-3 CS value. This tricky test checks that with
* one comparison. Many places in the kernel can bypass this full check
* if they have already ruled out V8086 mode, so user_mode(regs) can be used.
*/
static inline int user_mode(struct pt_regs *regs)
{
#ifdef CONFIG_X86_32
return (regs->cs & SEGMENT_RPL_MASK) == USER_RPL;
#else
return !!(regs->cs & 3);
#endif
}
static inline int user_mode_vm(struct pt_regs *regs)
{
#ifdef CONFIG_X86_32
return ((regs->cs & SEGMENT_RPL_MASK) | (regs->flags & X86_VM_MASK)) >=
USER_RPL;
#else
return user_mode(regs);
#endif
}
static inline int v8086_mode(struct pt_regs *regs)
{
#ifdef CONFIG_X86_32
return (regs->flags & X86_VM_MASK);
#else
return 0; /* No V86 mode support in long mode */
#endif
}
/*
* X86_32 CPUs don't save ss and esp if the CPU is already in kernel mode
* when it traps. The previous stack will be directly underneath the saved
* registers, and 'sp/ss' won't even have been saved. Thus the '®s->sp'.
*
* This is valid only for kernel mode traps.
*/
static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
{
#ifdef CONFIG_X86_32
return (unsigned long)(®s->sp);
#else
return regs->sp;
#endif
}
static inline unsigned long instruction_pointer(struct pt_regs *regs)
{
return regs->ip;
}
static inline unsigned long frame_pointer(struct pt_regs *regs)
{
return regs->bp;
}
static inline unsigned long user_stack_pointer(struct pt_regs *regs)
{
return regs->sp;
}
/* Query offset/name of register from its name/offset */
extern int regs_query_register_offset(const char *name);
extern const char *regs_query_register_name(unsigned int offset);
#define MAX_REG_OFFSET (offsetof(struct pt_regs, ss))
/**
* regs_get_register() - get register value from its offset
* @regs: pt_regs from which register value is gotten.
* @offset: offset number of the register.
*
* regs_get_register returns the value of a register. The @offset is the
* offset of the register in struct pt_regs address which specified by @regs.
* If @offset is bigger than MAX_REG_OFFSET, this returns 0.
*/
static inline unsigned long regs_get_register(struct pt_regs *regs,
unsigned int offset)
{
if (unlikely(offset > MAX_REG_OFFSET))
return 0;
return *(unsigned long *)((unsigned long)regs + offset);
}
/**
* regs_within_kernel_stack() - check the address in the stack
* @regs: pt_regs which contains kernel stack pointer.
* @addr: address which is checked.
*
* regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
* If @addr is within the kernel stack, it returns true. If not, returns false.
*/
static inline int regs_within_kernel_stack(struct pt_regs *regs,
unsigned long addr)
{
return ((addr & ~(THREAD_SIZE - 1)) ==
(kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)));
}
/**
* regs_get_kernel_stack_nth() - get Nth entry of the stack
* @regs: pt_regs which contains kernel stack pointer.
* @n: stack entry number.
*
* regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
* is specified by @regs. If the @n th entry is NOT in the kernel stack,
* this returns 0.
*/
static inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
unsigned int n)
{
unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
addr += n;
if (regs_within_kernel_stack(regs, (unsigned long)addr))
return *addr;
else
return 0;
}
/*
* These are defined as per linux/ptrace.h, which see.
*/
#define arch_has_single_step() (1)
extern void user_enable_single_step(struct task_struct *);
extern void user_disable_single_step(struct task_struct *);
extern void user_enable_block_step(struct task_struct *);
#ifdef CONFIG_X86_DEBUGCTLMSR
#define arch_has_block_step() (1)
#else
#define arch_has_block_step() (boot_cpu_data.x86 >= 6)
#endif
#define ARCH_HAS_USER_SINGLE_STEP_INFO
struct user_desc;
extern int do_get_thread_area(struct task_struct *p, int idx,
struct user_desc __user *info);
extern int do_set_thread_area(struct task_struct *p, int idx,
struct user_desc __user *info, int can_allocate);
#ifdef CONFIG_X86_PTRACE_BTS
extern void ptrace_bts_untrace(struct task_struct *tsk);
#define arch_ptrace_untrace(tsk) ptrace_bts_untrace(tsk)
#endif /* CONFIG_X86_PTRACE_BTS */
#endif /* __KERNEL__ */
#endif /* !__ASSEMBLY__ */
#endif /* _ASM_X86_PTRACE_H */
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