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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 | /* * 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); /* 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) { 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"); /* * 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; call_usermodehelper_fns("/linuxrc", argv, envp_init, UMH_WAIT_PROC, init_linuxrc, NULL, NULL); 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"); } } int __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 1; } } sys_unlink("/initrd.image"); return 0; } |