#define __KERNEL_SYSCALLS__ #include <linux/unistd.h> #include <linux/kernel.h> #include <linux/fs.h> #include <linux/minix_fs.h> #include <linux/ext2_fs.h> #include <linux/romfs_fs.h> #include <linux/initrd.h> #include <linux/sched.h> #include "do_mounts.h" unsigned long initrd_start, initrd_end; int initrd_below_start_ok; unsigned int real_root_dev; /* do_proc_dointvec cannot handle kdev_t */ static int __initdata old_fd, root_fd; static int __initdata mount_initrd = 1; static int __init no_initrd(char *str) { mount_initrd = 0; return 1; } __setup("noinitrd", no_initrd); static int __init do_linuxrc(void * shell) { static char *argv[] = { "linuxrc", NULL, }; extern char * envp_init[]; sys_close(old_fd);sys_close(root_fd); sys_close(0);sys_close(1);sys_close(2); sys_setsid(); (void) sys_open("/dev/console",O_RDWR,0); (void) sys_dup(0); (void) sys_dup(0); return execve(shell, argv, envp_init); } static void __init handle_initrd(void) { int error; int pid; real_root_dev = new_encode_dev(ROOT_DEV); create_dev("/dev/root.old", Root_RAM0, NULL); /* mount initrd on rootfs' /root */ mount_block_root("/dev/root.old", root_mountflags & ~MS_RDONLY); sys_mkdir("/old", 0700); root_fd = sys_open("/", 0, 0); old_fd = sys_open("/old", 0, 0); /* move initrd over / and chdir/chroot in initrd root */ sys_chdir("/root"); sys_mount(".", "/", NULL, MS_MOVE, NULL); sys_chroot("."); mount_devfs_fs (); pid = kernel_thread(do_linuxrc, "/linuxrc", SIGCHLD); if (pid > 0) { while (pid != sys_wait4(-1, NULL, 0, NULL)) yield(); } /* move initrd to rootfs' /old */ sys_fchdir(old_fd); sys_mount("/", ".", NULL, MS_MOVE, NULL); /* switch root and cwd back to / of rootfs */ sys_fchdir(root_fd); sys_chroot("."); sys_close(old_fd); sys_close(root_fd); umount_devfs("/old/dev"); if (new_decode_dev(real_root_dev) == Root_RAM0) { sys_chdir("/old"); return; } ROOT_DEV = new_decode_dev(real_root_dev); mount_root(); printk(KERN_NOTICE "Trying to move old root to /initrd ... "); error = sys_mount("/old", "/root/initrd", NULL, MS_MOVE, NULL); if (!error) printk("okay\n"); else { int fd = sys_open("/dev/root.old", O_RDWR, 0); if (error == -ENOENT) printk("/initrd does not exist. Ignored.\n"); else printk("failed\n"); printk(KERN_NOTICE "Unmounting old root\n"); sys_umount("/old", MNT_DETACH); printk(KERN_NOTICE "Trying to free ramdisk memory ... "); if (fd < 0) { error = fd; } else { error = sys_ioctl(fd, BLKFLSBUF, 0); sys_close(fd); } printk(!error ? "okay\n" : "failed\n"); } } int __init initrd_load(void) { if (mount_initrd) { create_dev("/dev/ram", Root_RAM0, NULL); /* * 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) { sys_unlink("/initrd.image"); handle_initrd(); return 1; } } sys_unlink("/initrd.image"); return 0; }