1/*
2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL
4 */
5
6#include <linux/init.h>
7#include <linux/bootmem.h>
8#include <linux/initrd.h>
9#include <asm/types.h>
10#include <init.h>
11#include <os.h>
12
13/* Changed by uml_initrd_setup, which is a setup */
14static char *initrd __initdata = NULL;
15static int load_initrd(char *filename, void *buf, int size);
16
17static int __init read_initrd(void)
18{
19	void *area;
20	long long size;
21	int err;
22
23	if (initrd == NULL)
24		return 0;
25
26	err = os_file_size(initrd, &size);
27	if (err)
28		return 0;
29
30	/*
31	 * This is necessary because alloc_bootmem craps out if you
32	 * ask for no memory.
33	 */
34	if (size == 0) {
35		printk(KERN_ERR "\"%s\" is a zero-size initrd\n", initrd);
36		return 0;
37	}
38
39	area = alloc_bootmem(size);
40	if (area == NULL)
41		return 0;
42
43	if (load_initrd(initrd, area, size) == -1)
44		return 0;
45
46	initrd_start = (unsigned long) area;
47	initrd_end = initrd_start + size;
48	return 0;
49}
50
51__uml_postsetup(read_initrd);
52
53static int __init uml_initrd_setup(char *line, int *add)
54{
55	initrd = line;
56	return 0;
57}
58
59__uml_setup("initrd=", uml_initrd_setup,
60"initrd=<initrd image>\n"
61"    This is used to boot UML from an initrd image.  The argument is the\n"
62"    name of the file containing the image.\n\n"
63);
64
65static int load_initrd(char *filename, void *buf, int size)
66{
67	int fd, n;
68
69	fd = os_open_file(filename, of_read(OPENFLAGS()), 0);
70	if (fd < 0) {
71		printk(KERN_ERR "Opening '%s' failed - err = %d\n", filename,
72		       -fd);
73		return -1;
74	}
75	n = os_read_file(fd, buf, size);
76	if (n != size) {
77		printk(KERN_ERR "Read of %d bytes from '%s' failed, "
78		       "err = %d\n", size,
79		       filename, -n);
80		return -1;
81	}
82
83	os_close_file(fd);
84	return 0;
85}
86