Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
2 | #include <linux/unistd.h> |
3 | #include <linux/kernel.h> | |
4 | #include <linux/fs.h> | |
5 | #include <linux/minix_fs.h> | |
1da177e4 LT |
6 | #include <linux/romfs_fs.h> |
7 | #include <linux/initrd.h> | |
8 | #include <linux/sched.h> | |
7dfb7103 | 9 | #include <linux/freezer.h> |
ba4df280 | 10 | #include <linux/kmod.h> |
e262e32d | 11 | #include <uapi/linux/mount.h> |
1da177e4 LT |
12 | |
13 | #include "do_mounts.h" | |
14 | ||
15 | unsigned long initrd_start, initrd_end; | |
16 | int initrd_below_start_ok; | |
17 | unsigned int real_root_dev; /* do_proc_dointvec cannot handle kdev_t */ | |
1da177e4 LT |
18 | static int __initdata mount_initrd = 1; |
19 | ||
b1ab95c6 FF |
20 | phys_addr_t phys_initrd_start __initdata; |
21 | unsigned long phys_initrd_size __initdata; | |
22 | ||
1da177e4 LT |
23 | static int __init no_initrd(char *str) |
24 | { | |
25 | mount_initrd = 0; | |
26 | return 1; | |
27 | } | |
28 | ||
29 | __setup("noinitrd", no_initrd); | |
30 | ||
694cfd87 | 31 | static int __init early_initrdmem(char *p) |
229c55cc FF |
32 | { |
33 | phys_addr_t start; | |
34 | unsigned long size; | |
35 | char *endp; | |
36 | ||
37 | start = memparse(p, &endp); | |
38 | if (*endp == ',') { | |
39 | size = memparse(endp + 1, NULL); | |
40 | ||
41 | phys_initrd_start = start; | |
42 | phys_initrd_size = size; | |
43 | } | |
44 | return 0; | |
45 | } | |
694cfd87 RM |
46 | early_param("initrdmem", early_initrdmem); |
47 | ||
48 | /* | |
49 | * This is here as the initrd keyword has been in use since 11/2018 | |
50 | * on ARM, PowerPC, and MIPS. | |
51 | * It should not be; it is reserved for bootloaders. | |
52 | */ | |
53 | static int __init early_initrd(char *p) | |
54 | { | |
55 | return early_initrdmem(p); | |
56 | } | |
229c55cc FF |
57 | early_param("initrd", early_initrd); |
58 | ||
f0ea68f1 | 59 | static int __init init_linuxrc(struct subprocess_info *info, struct cred *new) |
1da177e4 | 60 | { |
9b32105e | 61 | ksys_unshare(CLONE_FS | CLONE_FILES); |
b49a733d | 62 | console_on_rootfs(); |
ba4df280 | 63 | /* move initrd over / and chdir/chroot in initrd root */ |
447016e9 | 64 | ksys_chdir("/root"); |
d4440aac | 65 | do_mount(".", "/", NULL, MS_MOVE, NULL); |
a16fe33a | 66 | ksys_chroot("."); |
e2aaa9f4 | 67 | ksys_setsid(); |
ba4df280 | 68 | return 0; |
1da177e4 LT |
69 | } |
70 | ||
71 | static void __init handle_initrd(void) | |
72 | { | |
907ed132 | 73 | struct subprocess_info *info; |
ba4df280 AV |
74 | static char *argv[] = { "linuxrc", NULL, }; |
75 | extern char *envp_init[]; | |
1da177e4 | 76 | int error; |
1da177e4 LT |
77 | |
78 | real_root_dev = new_encode_dev(ROOT_DEV); | |
bdaf8529 | 79 | create_dev("/dev/root.old", Root_RAM0); |
1da177e4 LT |
80 | /* mount initrd on rootfs' /root */ |
81 | mount_block_root("/dev/root.old", root_mountflags & ~MS_RDONLY); | |
0101db7a | 82 | ksys_mkdir("/old", 0700); |
447016e9 | 83 | ksys_chdir("/old"); |
1da177e4 | 84 | |
8baabde6 RW |
85 | /* |
86 | * In case that a resume from disk is carried out by linuxrc or one of | |
87 | * its children, we need to tell the freezer not to wait for us. | |
88 | */ | |
89 | current->flags |= PF_FREEZER_SKIP; | |
90 | ||
907ed132 LDM |
91 | info = call_usermodehelper_setup("/linuxrc", argv, envp_init, |
92 | GFP_KERNEL, init_linuxrc, NULL, NULL); | |
93 | if (!info) | |
94 | return; | |
95 | call_usermodehelper_exec(info, UMH_WAIT_PROC); | |
8baabde6 RW |
96 | |
97 | current->flags &= ~PF_FREEZER_SKIP; | |
1da177e4 LT |
98 | |
99 | /* move initrd to rootfs' /old */ | |
d4440aac | 100 | do_mount("..", ".", NULL, MS_MOVE, NULL); |
1da177e4 | 101 | /* switch root and cwd back to / of rootfs */ |
a16fe33a | 102 | ksys_chroot(".."); |
1da177e4 LT |
103 | |
104 | if (new_decode_dev(real_root_dev) == Root_RAM0) { | |
447016e9 | 105 | ksys_chdir("/old"); |
1da177e4 LT |
106 | return; |
107 | } | |
108 | ||
447016e9 | 109 | ksys_chdir("/"); |
1da177e4 LT |
110 | ROOT_DEV = new_decode_dev(real_root_dev); |
111 | mount_root(); | |
112 | ||
113 | printk(KERN_NOTICE "Trying to move old root to /initrd ... "); | |
d4440aac | 114 | error = do_mount("/old", "/root/initrd", NULL, MS_MOVE, NULL); |
1da177e4 LT |
115 | if (!error) |
116 | printk("okay\n"); | |
117 | else { | |
f220ab2a JL |
118 | if (error == -ENOENT) |
119 | printk("/initrd does not exist. Ignored.\n"); | |
120 | else | |
121 | printk("failed\n"); | |
1da177e4 | 122 | printk(KERN_NOTICE "Unmounting old root\n"); |
3a18ef5c | 123 | ksys_umount("/old", MNT_DETACH); |
1da177e4 LT |
124 | } |
125 | } | |
126 | ||
f057f3b2 | 127 | bool __init initrd_load(void) |
1da177e4 LT |
128 | { |
129 | if (mount_initrd) { | |
bdaf8529 | 130 | create_dev("/dev/ram", Root_RAM0); |
1da177e4 LT |
131 | /* |
132 | * Load the initrd data into /dev/ram0. Execute it as initrd | |
133 | * unless /dev/ram0 is supposed to be our actual root device, | |
134 | * in that case the ram disk is just set up here, and gets | |
135 | * mounted in the normal path. | |
136 | */ | |
137 | if (rd_load_image("/initrd.image") && ROOT_DEV != Root_RAM0) { | |
0f32ab8c | 138 | ksys_unlink("/initrd.image"); |
1da177e4 | 139 | handle_initrd(); |
f057f3b2 | 140 | return true; |
1da177e4 LT |
141 | } |
142 | } | |
0f32ab8c | 143 | ksys_unlink("/initrd.image"); |
f057f3b2 | 144 | return false; |
1da177e4 | 145 | } |