arch/arm64/kernel/ptrace.c

Source file repositories/reference/linux-study-clean/arch/arm64/kernel/ptrace.c

File Facts

System
Linux kernel
Corpus path
arch/arm64/kernel/ptrace.c
Extension
.c
Size
61115 bytes
Lines
2530
Domain
Architecture Layer
Bucket
arch/arm64
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}
#define GPR_OFFSET_NAME(r) \
	{.name = "x" #r, .offset = offsetof(struct pt_regs, regs[r])}

static const struct pt_regs_offset regoffset_table[] = {
	GPR_OFFSET_NAME(0),
	GPR_OFFSET_NAME(1),
	GPR_OFFSET_NAME(2),
	GPR_OFFSET_NAME(3),
	GPR_OFFSET_NAME(4),
	GPR_OFFSET_NAME(5),
	GPR_OFFSET_NAME(6),
	GPR_OFFSET_NAME(7),
	GPR_OFFSET_NAME(8),
	GPR_OFFSET_NAME(9),
	GPR_OFFSET_NAME(10),
	GPR_OFFSET_NAME(11),
	GPR_OFFSET_NAME(12),
	GPR_OFFSET_NAME(13),
	GPR_OFFSET_NAME(14),
	GPR_OFFSET_NAME(15),
	GPR_OFFSET_NAME(16),
	GPR_OFFSET_NAME(17),
	GPR_OFFSET_NAME(18),
	GPR_OFFSET_NAME(19),
	GPR_OFFSET_NAME(20),
	GPR_OFFSET_NAME(21),
	GPR_OFFSET_NAME(22),
	GPR_OFFSET_NAME(23),
	GPR_OFFSET_NAME(24),
	GPR_OFFSET_NAME(25),
	GPR_OFFSET_NAME(26),
	GPR_OFFSET_NAME(27),
	GPR_OFFSET_NAME(28),
	GPR_OFFSET_NAME(29),
	GPR_OFFSET_NAME(30),
	{.name = "lr", .offset = offsetof(struct pt_regs, regs[30])},
	REG_OFFSET_NAME(sp),
	REG_OFFSET_NAME(pc),
	REG_OFFSET_NAME(pstate),
	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_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 bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
{
	return ((addr & ~(THREAD_SIZE - 1))  ==
		(kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1))) ||
		on_irq_stack(addr, sizeof(unsigned long));
}

/**
 * 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.
 */

Annotation

Implementation Notes