| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | #define __KERNEL_SYSCALLS__ |
| 2 | #include <linux/unistd.h> |
| 3 | #include <linux/kernel.h> |
| 4 | #include <linux/fs.h> |
| 5 | #include <linux/minix_fs.h> |
| 6 | #include <linux/ext2_fs.h> |
| 7 | #include <linux/romfs_fs.h> |
| 8 | #include <linux/initrd.h> |
| 9 | #include <linux/sched.h> |
| 10 | |
| 11 | #include "do_mounts.h" |
| 12 | |
| 13 | unsigned long initrd_start, initrd_end; |
| 14 | int initrd_below_start_ok; |
| 15 | unsigned int real_root_dev; /* do_proc_dointvec cannot handle kdev_t */ |
| 16 | static int __initdata old_fd, root_fd; |
| 17 | static int __initdata mount_initrd = 1; |
| 18 | |
| 19 | static int __init no_initrd(char *str) |
| 20 | { |
| 21 | mount_initrd = 0; |
| 22 | return 1; |
| 23 | } |
| 24 | |
| 25 | __setup("noinitrd", no_initrd); |
| 26 | |
| 27 | static int __init do_linuxrc(void * shell) |
| 28 | { |
| 29 | static char *argv[] = { "linuxrc", NULL, }; |
| 30 | extern char * envp_init[]; |
| 31 | |
| 32 | sys_close(old_fd);sys_close(root_fd); |
| 33 | sys_close(0);sys_close(1);sys_close(2); |
| 34 | sys_setsid(); |
| 35 | (void) sys_open("/dev/console",O_RDWR,0); |
| 36 | (void) sys_dup(0); |
| 37 | (void) sys_dup(0); |
| 38 | return execve(shell, argv, envp_init); |
| 39 | } |
| 40 | |
| 41 | static void __init handle_initrd(void) |
| 42 | { |
| 43 | int error; |
| 44 | int i, pid; |
| 45 | |
| 46 | real_root_dev = new_encode_dev(ROOT_DEV); |
| 47 | create_dev("/dev/root.old", Root_RAM0, NULL); |
| 48 | /* mount initrd on rootfs' /root */ |
| 49 | mount_block_root("/dev/root.old", root_mountflags & ~MS_RDONLY); |
| 50 | sys_mkdir("/old", 0700); |
| 51 | root_fd = sys_open("/", 0, 0); |
| 52 | old_fd = sys_open("/old", 0, 0); |
| 53 | /* move initrd over / and chdir/chroot in initrd root */ |
| 54 | sys_chdir("/root"); |
| 55 | sys_mount(".", "/", NULL, MS_MOVE, NULL); |
| 56 | sys_chroot("."); |
| 57 | mount_devfs_fs (); |
| 58 | |
| 59 | pid = kernel_thread(do_linuxrc, "/linuxrc", SIGCHLD); |
| 60 | if (pid > 0) { |
| 61 | while (pid != sys_wait4(-1, &i, 0, NULL)) |
| 62 | yield(); |
| 63 | } |
| 64 | |
| 65 | /* move initrd to rootfs' /old */ |
| 66 | sys_fchdir(old_fd); |
| 67 | sys_mount("/", ".", NULL, MS_MOVE, NULL); |
| 68 | /* switch root and cwd back to / of rootfs */ |
| 69 | sys_fchdir(root_fd); |
| 70 | sys_chroot("."); |
| 71 | sys_close(old_fd); |
| 72 | sys_close(root_fd); |
| 73 | umount_devfs("/old/dev"); |
| 74 | |
| 75 | if (new_decode_dev(real_root_dev) == Root_RAM0) { |
| 76 | sys_chdir("/old"); |
| 77 | return; |
| 78 | } |
| 79 | |
| 80 | ROOT_DEV = new_decode_dev(real_root_dev); |
| 81 | mount_root(); |
| 82 | |
| 83 | printk(KERN_NOTICE "Trying to move old root to /initrd ... "); |
| 84 | error = sys_mount("/old", "/root/initrd", NULL, MS_MOVE, NULL); |
| 85 | if (!error) |
| 86 | printk("okay\n"); |
| 87 | else { |
| 88 | int fd = sys_open("/dev/root.old", O_RDWR, 0); |
| 89 | printk("failed\n"); |
| 90 | printk(KERN_NOTICE "Unmounting old root\n"); |
| 91 | sys_umount("/old", MNT_DETACH); |
| 92 | printk(KERN_NOTICE "Trying to free ramdisk memory ... "); |
| 93 | if (fd < 0) { |
| 94 | error = fd; |
| 95 | } else { |
| 96 | error = sys_ioctl(fd, BLKFLSBUF, 0); |
| 97 | sys_close(fd); |
| 98 | } |
| 99 | printk(!error ? "okay\n" : "failed\n"); |
| 100 | } |
| 101 | } |
| 102 | |
| 103 | int __init initrd_load(void) |
| 104 | { |
| 105 | if (mount_initrd) { |
| 106 | create_dev("/dev/ram", Root_RAM0, NULL); |
| 107 | /* |
| 108 | * Load the initrd data into /dev/ram0. Execute it as initrd |
| 109 | * unless /dev/ram0 is supposed to be our actual root device, |
| 110 | * in that case the ram disk is just set up here, and gets |
| 111 | * mounted in the normal path. |
| 112 | */ |
| 113 | if (rd_load_image("/initrd.image") && ROOT_DEV != Root_RAM0) { |
| 114 | sys_unlink("/initrd.image"); |
| 115 | handle_initrd(); |
| 116 | return 1; |
| 117 | } |
| 118 | } |
| 119 | sys_unlink("/initrd.image"); |
| 120 | return 0; |
| 121 | } |