/* * Many of the syscalls used in this file expect some of the arguments * to be __user pointers not __kernel pointers. To limit the sparse * noise, turn off sparse checking for this file. */ #ifdef __CHECKER__ #undef __CHECKER__ #warning "Sparse checking disabled for this file" #endif #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 "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 mount_initrd = 1; static int __init no_initrd(char *str) { mount_initrd = 0; return 1; } __setup("noinitrd", no_initrd); static int init_linuxrc(struct subprocess_info *info, struct cred *new) { sys_unshare(CLONE_FS | CLONE_FILES); /* stdin/stdout/stderr for /linuxrc */ sys_open("/dev/console", O_RDWR, 0); sys_dup(0); sys_dup(0); /* move initrd over / and chdir/chroot in initrd root */ sys_chdir("/root"); sys_mount(".", "/", NULL, MS_MOVE, NULL); sys_chroot("."); sys_setsid(); return 0; } static void __init handle_initrd(void) { struct subprocess_info *info; static char *argv[] = { "linuxrc", NULL, }; extern char *envp_init[]; int error; 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); sys_mkdir("/old", 0700); sys_chdir("/old"); /* try loading default modules from initrd */ load_default_modules(); /* * In case that a resume from disk is carried out by linuxrc or one of * its children, we need to tell the freezer not to wait for us. */ current->flags |= PF_FREEZER_SKIP; info = call_usermodehelper_setup("/linuxrc", argv, envp_init, GFP_KERNEL, init_linuxrc, NULL, NULL); if (!info) return; call_usermodehelper_exec(info, UMH_WAIT_PROC); current->flags &= ~PF_FREEZER_SKIP; /* move initrd to rootfs' /old */ sys_mount("..", ".", NULL, MS_MOVE, NULL); /* switch root and cwd back to / of rootfs */ sys_chroot(".."); if (new_decode_dev(real_root_dev) == Root_RAM0) { sys_chdir("/old"); return; } sys_chdir("/"); 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"); } } 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) { sys_unlink("/initrd.image"); handle_initrd(); return true; } } sys_unlink("/initrd.image"); return false; }