arch/x86/kernel/ptrace.c

Source file repositories/reference/linux-study-clean/arch/x86/kernel/ptrace.c

File Facts

System
Linux kernel
Corpus path
arch/x86/kernel/ptrace.c
Extension
.c
Size
35873 bytes
Lines
1424
Domain
Architecture Layer
Bucket
arch/x86
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

struct pt_regs_offset {
	const char *name;
	int offset;
};

#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
#define REG_OFFSET_END {.name = NULL, .offset = 0}

static const struct pt_regs_offset regoffset_table[] = {
#ifdef CONFIG_X86_64
	REG_OFFSET_NAME(r15),
	REG_OFFSET_NAME(r14),
	REG_OFFSET_NAME(r13),
	REG_OFFSET_NAME(r12),
	REG_OFFSET_NAME(r11),
	REG_OFFSET_NAME(r10),
	REG_OFFSET_NAME(r9),
	REG_OFFSET_NAME(r8),
#endif
	REG_OFFSET_NAME(bx),
	REG_OFFSET_NAME(cx),
	REG_OFFSET_NAME(dx),
	REG_OFFSET_NAME(si),
	REG_OFFSET_NAME(di),
	REG_OFFSET_NAME(bp),
	REG_OFFSET_NAME(ax),
#ifdef CONFIG_X86_32
	REG_OFFSET_NAME(ds),
	REG_OFFSET_NAME(es),
	REG_OFFSET_NAME(fs),
	REG_OFFSET_NAME(gs),
#endif
	REG_OFFSET_NAME(orig_ax),
	REG_OFFSET_NAME(ip),
	REG_OFFSET_NAME(cs),
	REG_OFFSET_NAME(flags),
	REG_OFFSET_NAME(sp),
	REG_OFFSET_NAME(ss),
	REG_OFFSET_END,
};

/**
 * regs_query_register_offset() - query register offset from its name
 * @name:	the name of a register
 *
 * regs_query_register_offset() returns the offset of a register in struct
 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
 */
int regs_query_register_offset(const char *name)
{
	const struct pt_regs_offset *roff;
	for (roff = regoffset_table; roff->name != NULL; roff++)
		if (!strcmp(roff->name, name))
			return roff->offset;
	return -EINVAL;
}

/**
 * regs_query_register_name() - query register name from its offset
 * @offset:	the offset of a register in struct pt_regs.
 *
 * regs_query_register_name() returns the name of a register from its
 * offset in struct pt_regs. If the @offset is invalid, this returns NULL;
 */
const char *regs_query_register_name(unsigned int offset)
{
	const struct pt_regs_offset *roff;
	for (roff = regoffset_table; roff->name != NULL; roff++)
		if (roff->offset == offset)
			return roff->name;
	return NULL;
}

/*
 * does not yet catch signals sent when the child dies.
 * in exit.c or in signal.c.
 */

/*
 * Determines which flags the user has access to [1 = access, 0 = no access].
 */
#define FLAG_MASK_32		((unsigned long)			\
				 (X86_EFLAGS_CF | X86_EFLAGS_PF |	\
				  X86_EFLAGS_AF | X86_EFLAGS_ZF |	\
				  X86_EFLAGS_SF | X86_EFLAGS_TF |	\
				  X86_EFLAGS_DF | X86_EFLAGS_OF |	\
				  X86_EFLAGS_RF | X86_EFLAGS_AC))

/*
 * Determines whether a value may be installed in a segment register.

Annotation

Implementation Notes