Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

Open Menu /arch/um/os-Linux/registers.c 
 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2004 PathScale, Inc
 * Copyright (C) 2004 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 */

#include <errno.h>
#include <string.h>
#include <sys/ptrace.h>
#include <sysdep/ptrace.h>
#include <sysdep/ptrace_user.h>
#include <registers.h>

int save_registers(int pid, struct uml_pt_regs *regs)
{
	int err;

	err = ptrace(PTRACE_GETREGS, pid, 0, regs->gp);
	if (err < 0)
		return -errno;
	return 0;
}

int restore_registers(int pid, struct uml_pt_regs *regs)
{
	int err;

	err = ptrace(PTRACE_SETREGS, pid, 0, regs->gp);
	if (err < 0)
		return -errno;
	return 0;
}

/* This is set once at boot time and not changed thereafter */

static unsigned long exec_regs[MAX_REG_NR];
static unsigned long exec_fp_regs[FP_SIZE];

int init_registers(int pid)
{
	int err;

	err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs);
	if (err < 0)
		return -errno;

	arch_init_registers(pid);
	get_fp_registers(pid, exec_fp_regs);
	return 0;
}

void get_safe_registers(unsigned long *regs, unsigned long *fp_regs)
{
	memcpy(regs, exec_regs, sizeof(exec_regs));

	if (fp_regs)
		memcpy(fp_regs, exec_fp_regs, sizeof(exec_fp_regs));
}