1 #include <linux/module.h> 2 #include <linux/sched.h> 3 #include <linux/ctype.h> 4 #include <linux/fd.h> 5 #include <linux/tty.h> 6 #include <linux/suspend.h> 7 #include <linux/root_dev.h> 8 #include <linux/security.h> 9 #include <linux/delay.h> 10 #include <linux/genhd.h> 11 #include <linux/mount.h> 12 #include <linux/device.h> 13 #include <linux/init.h> 14 #include <linux/fs.h> 15 #include <linux/initrd.h> 16 #include <linux/async.h> 17 #include <linux/fs_struct.h> 18 #include <linux/slab.h> 19 20 #include <linux/nfs_fs.h> 21 #include <linux/nfs_fs_sb.h> 22 #include <linux/nfs_mount.h> 23 24 #include "do_mounts.h" 25 26 int __initdata rd_doload; /* 1 = load RAM disk, 0 = don't load */ 27 28 int root_mountflags = MS_RDONLY | MS_SILENT; 29 static char * __initdata root_device_name; 30 static char __initdata saved_root_name[64]; 31 static int __initdata root_wait; 32 33 dev_t ROOT_DEV; 34 35 static int __init load_ramdisk(char *str) 36 { 37 rd_doload = simple_strtol(str,NULL,0) & 3; 38 return 1; 39 } 40 __setup("load_ramdisk=", load_ramdisk); 41 42 static int __init readonly(char *str) 43 { 44 if (*str) 45 return 0; 46 root_mountflags |= MS_RDONLY; 47 return 1; 48 } 49 50 static int __init readwrite(char *str) 51 { 52 if (*str) 53 return 0; 54 root_mountflags &= ~MS_RDONLY; 55 return 1; 56 } 57 58 __setup("ro", readonly); 59 __setup("rw", readwrite); 60 61 #ifdef CONFIG_BLOCK 62 /** 63 * match_dev_by_uuid - callback for finding a partition using its uuid 64 * @dev: device passed in by the caller 65 * @data: opaque pointer to a 36 byte char array with a UUID 66 * 67 * Returns 1 if the device matches, and 0 otherwise. 68 */ 69 static int match_dev_by_uuid(struct device *dev, void *data) 70 { 71 u8 *uuid = data; 72 struct hd_struct *part = dev_to_part(dev); 73 74 if (!part->info) 75 goto no_match; 76 77 if (memcmp(uuid, part->info->uuid, sizeof(part->info->uuid))) 78 goto no_match; 79 80 return 1; 81 no_match: 82 return 0; 83 } 84 85 86 /** 87 * devt_from_partuuid - looks up the dev_t of a partition by its UUID 88 * @uuid: 36 byte char array containing a hex ascii UUID 89 * 90 * The function will return the first partition which contains a matching 91 * UUID value in its partition_meta_info struct. This does not search 92 * by filesystem UUIDs. 93 * 94 * Returns the matching dev_t on success or 0 on failure. 95 */ 96 static dev_t devt_from_partuuid(char *uuid_str) 97 { 98 dev_t res = 0; 99 struct device *dev = NULL; 100 u8 uuid[16]; 101 102 /* Pack the requested UUID in the expected format. */ 103 part_pack_uuid(uuid_str, uuid); 104 105 dev = class_find_device(&block_class, NULL, uuid, &match_dev_by_uuid); 106 if (!dev) 107 goto done; 108 109 res = dev->devt; 110 put_device(dev); 111 112 done: 113 return res; 114 } 115 #endif 116 117 /* 118 * Convert a name into device number. We accept the following variants: 119 * 120 * 1) device number in hexadecimal represents itself 121 * 2) /dev/nfs represents Root_NFS (0xff) 122 * 3) /dev/<disk_name> represents the device number of disk 123 * 4) /dev/<disk_name><decimal> represents the device number 124 * of partition - device number of disk plus the partition number 125 * 5) /dev/<disk_name>p<decimal> - same as the above, that form is 126 * used when disk name of partitioned disk ends on a digit. 127 * 6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the 128 * unique id of a partition if the partition table provides it. 129 * 130 * If name doesn't have fall into the categories above, we return (0,0). 131 * block_class is used to check if something is a disk name. If the disk 132 * name contains slashes, the device name has them replaced with 133 * bangs. 134 */ 135 136 dev_t name_to_dev_t(char *name) 137 { 138 char s[32]; 139 char *p; 140 dev_t res = 0; 141 int part; 142 143 #ifdef CONFIG_BLOCK 144 if (strncmp(name, "PARTUUID=", 9) == 0) { 145 name += 9; 146 if (strlen(name) != 36) 147 goto fail; 148 res = devt_from_partuuid(name); 149 if (!res) 150 goto fail; 151 goto done; 152 } 153 #endif 154 155 if (strncmp(name, "/dev/", 5) != 0) { 156 unsigned maj, min; 157 158 if (sscanf(name, "%u:%u", &maj, &min) == 2) { 159 res = MKDEV(maj, min); 160 if (maj != MAJOR(res) || min != MINOR(res)) 161 goto fail; 162 } else { 163 res = new_decode_dev(simple_strtoul(name, &p, 16)); 164 if (*p) 165 goto fail; 166 } 167 goto done; 168 } 169 170 name += 5; 171 res = Root_NFS; 172 if (strcmp(name, "nfs") == 0) 173 goto done; 174 res = Root_RAM0; 175 if (strcmp(name, "ram") == 0) 176 goto done; 177 178 if (strlen(name) > 31) 179 goto fail; 180 strcpy(s, name); 181 for (p = s; *p; p++) 182 if (*p == '/') 183 *p = '!'; 184 res = blk_lookup_devt(s, 0); 185 if (res) 186 goto done; 187 188 /* 189 * try non-existent, but valid partition, which may only exist 190 * after revalidating the disk, like partitioned md devices 191 */ 192 while (p > s && isdigit(p[-1])) 193 p--; 194 if (p == s || !*p || *p == '0') 195 goto fail; 196 197 /* try disk name without <part number> */ 198 part = simple_strtoul(p, NULL, 10); 199 *p = '\0'; 200 res = blk_lookup_devt(s, part); 201 if (res) 202 goto done; 203 204 /* try disk name without p<part number> */ 205 if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p') 206 goto fail; 207 p[-1] = '\0'; 208 res = blk_lookup_devt(s, part); 209 if (res) 210 goto done; 211 212 fail: 213 return 0; 214 done: 215 return res; 216 } 217 218 static int __init root_dev_setup(char *line) 219 { 220 strlcpy(saved_root_name, line, sizeof(saved_root_name)); 221 return 1; 222 } 223 224 __setup("root=", root_dev_setup); 225 226 static int __init rootwait_setup(char *str) 227 { 228 if (*str) 229 return 0; 230 root_wait = 1; 231 return 1; 232 } 233 234 __setup("rootwait", rootwait_setup); 235 236 static char * __initdata root_mount_data; 237 static int __init root_data_setup(char *str) 238 { 239 root_mount_data = str; 240 return 1; 241 } 242 243 static char * __initdata root_fs_names; 244 static int __init fs_names_setup(char *str) 245 { 246 root_fs_names = str; 247 return 1; 248 } 249 250 static unsigned int __initdata root_delay; 251 static int __init root_delay_setup(char *str) 252 { 253 root_delay = simple_strtoul(str, NULL, 0); 254 return 1; 255 } 256 257 __setup("rootflags=", root_data_setup); 258 __setup("rootfstype=", fs_names_setup); 259 __setup("rootdelay=", root_delay_setup); 260 261 static void __init get_fs_names(char *page) 262 { 263 char *s = page; 264 265 if (root_fs_names) { 266 strcpy(page, root_fs_names); 267 while (*s++) { 268 if (s[-1] == ',') 269 s[-1] = '\0'; 270 } 271 } else { 272 int len = get_filesystem_list(page); 273 char *p, *next; 274 275 page[len] = '\0'; 276 for (p = page-1; p; p = next) { 277 next = strchr(++p, '\n'); 278 if (*p++ != '\t') 279 continue; 280 while ((*s++ = *p++) != '\n') 281 ; 282 s[-1] = '\0'; 283 } 284 } 285 *s = '\0'; 286 } 287 288 static int __init do_mount_root(char *name, char *fs, int flags, void *data) 289 { 290 int err = sys_mount(name, "/root", fs, flags, data); 291 if (err) 292 return err; 293 294 sys_chdir((const char __user __force *)"/root"); 295 ROOT_DEV = current->fs->pwd.mnt->mnt_sb->s_dev; 296 printk(KERN_INFO 297 "VFS: Mounted root (%s filesystem)%s on device %u:%u.\n", 298 current->fs->pwd.mnt->mnt_sb->s_type->name, 299 current->fs->pwd.mnt->mnt_sb->s_flags & MS_RDONLY ? 300 " readonly" : "", MAJOR(ROOT_DEV), MINOR(ROOT_DEV)); 301 return 0; 302 } 303 304 void __init mount_block_root(char *name, int flags) 305 { 306 char *fs_names = __getname_gfp(GFP_KERNEL 307 | __GFP_NOTRACK_FALSE_POSITIVE); 308 char *p; 309 #ifdef CONFIG_BLOCK 310 char b[BDEVNAME_SIZE]; 311 #else 312 const char *b = name; 313 #endif 314 315 get_fs_names(fs_names); 316 retry: 317 for (p = fs_names; *p; p += strlen(p)+1) { 318 int err = do_mount_root(name, p, flags, root_mount_data); 319 switch (err) { 320 case 0: 321 goto out; 322 case -EACCES: 323 flags |= MS_RDONLY; 324 goto retry; 325 case -EINVAL: 326 continue; 327 } 328 /* 329 * Allow the user to distinguish between failed sys_open 330 * and bad superblock on root device. 331 * and give them a list of the available devices 332 */ 333 #ifdef CONFIG_BLOCK 334 __bdevname(ROOT_DEV, b); 335 #endif 336 printk("VFS: Cannot open root device \"%s\" or %s\n", 337 root_device_name, b); 338 printk("Please append a correct \"root=\" boot option; here are the available partitions:\n"); 339 340 printk_all_partitions(); 341 #ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT 342 printk("DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify " 343 "explicit textual name for \"root=\" boot option.\n"); 344 #endif 345 panic("VFS: Unable to mount root fs on %s", b); 346 } 347 348 printk("List of all partitions:\n"); 349 printk_all_partitions(); 350 printk("No filesystem could mount root, tried: "); 351 for (p = fs_names; *p; p += strlen(p)+1) 352 printk(" %s", p); 353 printk("\n"); 354 #ifdef CONFIG_BLOCK 355 __bdevname(ROOT_DEV, b); 356 #endif 357 panic("VFS: Unable to mount root fs on %s", b); 358 out: 359 putname(fs_names); 360 } 361 362 #ifdef CONFIG_ROOT_NFS 363 static int __init mount_nfs_root(void) 364 { 365 char *root_dev, *root_data; 366 367 if (nfs_root_data(&root_dev, &root_data) != 0) 368 return 0; 369 if (do_mount_root(root_dev, "nfs", root_mountflags, root_data) != 0) 370 return 0; 371 return 1; 372 } 373 #endif 374 375 #if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD) 376 void __init change_floppy(char *fmt, ...) 377 { 378 struct termios termios; 379 char buf[80]; 380 char c; 381 int fd; 382 va_list args; 383 va_start(args, fmt); 384 vsprintf(buf, fmt, args); 385 va_end(args); 386 fd = sys_open("/dev/root", O_RDWR | O_NDELAY, 0); 387 if (fd >= 0) { 388 sys_ioctl(fd, FDEJECT, 0); 389 sys_close(fd); 390 } 391 printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf); 392 fd = sys_open("/dev/console", O_RDWR, 0); 393 if (fd >= 0) { 394 sys_ioctl(fd, TCGETS, (long)&termios); 395 termios.c_lflag &= ~ICANON; 396 sys_ioctl(fd, TCSETSF, (long)&termios); 397 sys_read(fd, &c, 1); 398 termios.c_lflag |= ICANON; 399 sys_ioctl(fd, TCSETSF, (long)&termios); 400 sys_close(fd); 401 } 402 } 403 #endif 404 405 void __init mount_root(void) 406 { 407 #ifdef CONFIG_ROOT_NFS 408 if (MAJOR(ROOT_DEV) == UNNAMED_MAJOR) { 409 if (mount_nfs_root()) 410 return; 411 412 printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n"); 413 ROOT_DEV = Root_FD0; 414 } 415 #endif 416 #ifdef CONFIG_BLK_DEV_FD 417 if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) { 418 /* rd_doload is 2 for a dual initrd/ramload setup */ 419 if (rd_doload==2) { 420 if (rd_load_disk(1)) { 421 ROOT_DEV = Root_RAM1; 422 root_device_name = NULL; 423 } 424 } else 425 change_floppy("root floppy"); 426 } 427 #endif 428 #ifdef CONFIG_BLOCK 429 create_dev("/dev/root", ROOT_DEV); 430 mount_block_root("/dev/root", root_mountflags); 431 #endif 432 } 433 434 /* 435 * Prepare the namespace - decide what/where to mount, load ramdisks, etc. 436 */ 437 void __init prepare_namespace(void) 438 { 439 int is_floppy; 440 441 if (root_delay) { 442 printk(KERN_INFO "Waiting %dsec before mounting root device...\n", 443 root_delay); 444 ssleep(root_delay); 445 } 446 447 /* 448 * wait for the known devices to complete their probing 449 * 450 * Note: this is a potential source of long boot delays. 451 * For example, it is not atypical to wait 5 seconds here 452 * for the touchpad of a laptop to initialize. 453 */ 454 wait_for_device_probe(); 455 456 md_run_setup(); 457 458 if (saved_root_name[0]) { 459 root_device_name = saved_root_name; 460 if (!strncmp(root_device_name, "mtd", 3) || 461 !strncmp(root_device_name, "ubi", 3)) { 462 mount_block_root(root_device_name, root_mountflags); 463 goto out; 464 } 465 ROOT_DEV = name_to_dev_t(root_device_name); 466 if (strncmp(root_device_name, "/dev/", 5) == 0) 467 root_device_name += 5; 468 } 469 470 if (initrd_load()) 471 goto out; 472 473 /* wait for any asynchronous scanning to complete */ 474 if ((ROOT_DEV == 0) && root_wait) { 475 printk(KERN_INFO "Waiting for root device %s...\n", 476 saved_root_name); 477 while (driver_probe_done() != 0 || 478 (ROOT_DEV = name_to_dev_t(saved_root_name)) == 0) 479 msleep(100); 480 async_synchronize_full(); 481 } 482 483 is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR; 484 485 if (is_floppy && rd_doload && rd_load_disk(0)) 486 ROOT_DEV = Root_RAM0; 487 488 mount_root(); 489 out: 490 devtmpfs_mount("dev"); 491 sys_mount(".", "/", NULL, MS_MOVE, NULL); 492 sys_chroot((const char __user __force *)"."); 493 } 494