Loading...
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 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 | // SPDX-License-Identifier: GPL-2.0 #include <linux/unistd.h> #include <linux/kernel.h> #include <linux/fs.h> #include <linux/minix_fs.h> #include <linux/romfs_fs.h> #include <linux/initrd.h> #include <linux/sched.h> #include <linux/freezer.h> #include <linux/kmod.h> #include <uapi/linux/mount.h> #include "do_mounts.h" unsigned long initrd_start, initrd_end; int initrd_below_start_ok; static unsigned int real_root_dev; /* do_proc_dointvec cannot handle kdev_t */ static int __initdata mount_initrd = 1; phys_addr_t phys_initrd_start __initdata; unsigned long phys_initrd_size __initdata; #ifdef CONFIG_SYSCTL static struct ctl_table kern_do_mounts_initrd_table[] = { { .procname = "real-root-dev", .data = &real_root_dev, .maxlen = sizeof(int), .mode = 0644, .proc_handler = proc_dointvec, }, { } }; static __init int kernel_do_mounts_initrd_sysctls_init(void) { register_sysctl_init("kernel", kern_do_mounts_initrd_table); return 0; } late_initcall(kernel_do_mounts_initrd_sysctls_init); #endif /* CONFIG_SYSCTL */ static int __init no_initrd(char *str) { mount_initrd = 0; return 1; } __setup("noinitrd", no_initrd); static int __init early_initrdmem(char *p) { phys_addr_t start; unsigned long size; char *endp; start = memparse(p, &endp); if (*endp == ',') { size = memparse(endp + 1, NULL); phys_initrd_start = start; phys_initrd_size = size; } return 0; } early_param("initrdmem", early_initrdmem); static int __init early_initrd(char *p) { return early_initrdmem(p); } early_param("initrd", early_initrd); static int __init init_linuxrc(struct subprocess_info *info, struct cred *new) { ksys_unshare(CLONE_FS | CLONE_FILES); console_on_rootfs(); /* move initrd over / and chdir/chroot in initrd root */ init_chdir("/root"); init_mount(".", "/", NULL, MS_MOVE, NULL); init_chroot("."); ksys_setsid(); return 0; } static void __init handle_initrd(void) { struct subprocess_info *info; static char *argv[] = { "linuxrc", NULL, }; extern char *envp_init[]; int error; pr_warn("using deprecated initrd support, will be removed in 2021.\n"); real_root_dev = new_encode_dev(ROOT_DEV); create_dev("/dev/root.old", Root_RAM0); /* mount initrd on rootfs' /root */ mount_block_root("/dev/root.old", root_mountflags & ~MS_RDONLY); init_mkdir("/old", 0700); init_chdir("/old"); info = call_usermodehelper_setup("/linuxrc", argv, envp_init, GFP_KERNEL, init_linuxrc, NULL, NULL); if (!info) return; call_usermodehelper_exec(info, UMH_WAIT_PROC|UMH_FREEZABLE); /* move initrd to rootfs' /old */ init_mount("..", ".", NULL, MS_MOVE, NULL); /* switch root and cwd back to / of rootfs */ init_chroot(".."); if (new_decode_dev(real_root_dev) == Root_RAM0) { init_chdir("/old"); return; } init_chdir("/"); ROOT_DEV = new_decode_dev(real_root_dev); mount_root(); printk(KERN_NOTICE "Trying to move old root to /initrd ... "); error = init_mount("/old", "/root/initrd", NULL, MS_MOVE, NULL); if (!error) printk("okay\n"); else { if (error == -ENOENT) printk("/initrd does not exist. Ignored.\n"); else printk("failed\n"); printk(KERN_NOTICE "Unmounting old root\n"); init_umount("/old", MNT_DETACH); } } bool __init initrd_load(void) { if (mount_initrd) { create_dev("/dev/ram", Root_RAM0); /* * Load the initrd data into /dev/ram0. Execute it as initrd * unless /dev/ram0 is supposed to be our actual root device, * in that case the ram disk is just set up here, and gets * mounted in the normal path. */ if (rd_load_image("/initrd.image") && ROOT_DEV != Root_RAM0) { init_unlink("/initrd.image"); handle_initrd(); return true; } } init_unlink("/initrd.image"); return false; } |