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 __init 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-existant, 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("VFS: Mounted root (%s filesystem)%s on device %u:%u.\n", 297 current->fs->pwd.mnt->mnt_sb->s_type->name, 298 current->fs->pwd.mnt->mnt_sb->s_flags & MS_RDONLY ? 299 " readonly" : "", MAJOR(ROOT_DEV), MINOR(ROOT_DEV)); 300 return 0; 301 } 302 303 void __init mount_block_root(char *name, int flags) 304 { 305 char *fs_names = __getname_gfp(GFP_KERNEL 306 | __GFP_NOTRACK_FALSE_POSITIVE); 307 char *p; 308 #ifdef CONFIG_BLOCK 309 char b[BDEVNAME_SIZE]; 310 #else 311 const char *b = name; 312 #endif 313 314 get_fs_names(fs_names); 315 retry: 316 for (p = fs_names; *p; p += strlen(p)+1) { 317 int err = do_mount_root(name, p, flags, root_mount_data); 318 switch (err) { 319 case 0: 320 goto out; 321 case -EACCES: 322 flags |= MS_RDONLY; 323 goto retry; 324 case -EINVAL: 325 continue; 326 } 327 /* 328 * Allow the user to distinguish between failed sys_open 329 * and bad superblock on root device. 330 * and give them a list of the available devices 331 */ 332 #ifdef CONFIG_BLOCK 333 __bdevname(ROOT_DEV, b); 334 #endif 335 printk("VFS: Cannot open root device \"%s\" or %s\n", 336 root_device_name, b); 337 printk("Please append a correct \"root=\" boot option; here are the available partitions:\n"); 338 339 printk_all_partitions(); 340 #ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT 341 printk("DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify " 342 "explicit textual name for \"root=\" boot option.\n"); 343 #endif 344 panic("VFS: Unable to mount root fs on %s", b); 345 } 346 347 printk("List of all partitions:\n"); 348 printk_all_partitions(); 349 printk("No filesystem could mount root, tried: "); 350 for (p = fs_names; *p; p += strlen(p)+1) 351 printk(" %s", p); 352 printk("\n"); 353 #ifdef CONFIG_BLOCK 354 __bdevname(ROOT_DEV, b); 355 #endif 356 panic("VFS: Unable to mount root fs on %s", b); 357 out: 358 putname(fs_names); 359 } 360 361 #ifdef CONFIG_ROOT_NFS 362 static int __init mount_nfs_root(void) 363 { 364 char *root_dev, *root_data; 365 366 if (nfs_root_data(&root_dev, &root_data) != 0) 367 return 0; 368 if (do_mount_root(root_dev, "nfs", root_mountflags, root_data) != 0) 369 return 0; 370 return 1; 371 } 372 #endif 373 374 #if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD) 375 void __init change_floppy(char *fmt, ...) 376 { 377 struct termios termios; 378 char buf[80]; 379 char c; 380 int fd; 381 va_list args; 382 va_start(args, fmt); 383 vsprintf(buf, fmt, args); 384 va_end(args); 385 fd = sys_open("/dev/root", O_RDWR | O_NDELAY, 0); 386 if (fd >= 0) { 387 sys_ioctl(fd, FDEJECT, 0); 388 sys_close(fd); 389 } 390 printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf); 391 fd = sys_open("/dev/console", O_RDWR, 0); 392 if (fd >= 0) { 393 sys_ioctl(fd, TCGETS, (long)&termios); 394 termios.c_lflag &= ~ICANON; 395 sys_ioctl(fd, TCSETSF, (long)&termios); 396 sys_read(fd, &c, 1); 397 termios.c_lflag |= ICANON; 398 sys_ioctl(fd, TCSETSF, (long)&termios); 399 sys_close(fd); 400 } 401 } 402 #endif 403 404 void __init mount_root(void) 405 { 406 #ifdef CONFIG_ROOT_NFS 407 if (MAJOR(ROOT_DEV) == UNNAMED_MAJOR) { 408 if (mount_nfs_root()) 409 return; 410 411 printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n"); 412 ROOT_DEV = Root_FD0; 413 } 414 #endif 415 #ifdef CONFIG_BLK_DEV_FD 416 if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) { 417 /* rd_doload is 2 for a dual initrd/ramload setup */ 418 if (rd_doload==2) { 419 if (rd_load_disk(1)) { 420 ROOT_DEV = Root_RAM1; 421 root_device_name = NULL; 422 } 423 } else 424 change_floppy("root floppy"); 425 } 426 #endif 427 #ifdef CONFIG_BLOCK 428 create_dev("/dev/root", ROOT_DEV); 429 mount_block_root("/dev/root", root_mountflags); 430 #endif 431 } 432 433 /* 434 * Prepare the namespace - decide what/where to mount, load ramdisks, etc. 435 */ 436 void __init prepare_namespace(void) 437 { 438 int is_floppy; 439 440 if (root_delay) { 441 printk(KERN_INFO "Waiting %dsec before mounting root device...\n", 442 root_delay); 443 ssleep(root_delay); 444 } 445 446 /* 447 * wait for the known devices to complete their probing 448 * 449 * Note: this is a potential source of long boot delays. 450 * For example, it is not atypical to wait 5 seconds here 451 * for the touchpad of a laptop to initialize. 452 */ 453 wait_for_device_probe(); 454 455 md_run_setup(); 456 457 if (saved_root_name[0]) { 458 root_device_name = saved_root_name; 459 if (!strncmp(root_device_name, "mtd", 3) || 460 !strncmp(root_device_name, "ubi", 3)) { 461 mount_block_root(root_device_name, root_mountflags); 462 goto out; 463 } 464 ROOT_DEV = name_to_dev_t(root_device_name); 465 if (strncmp(root_device_name, "/dev/", 5) == 0) 466 root_device_name += 5; 467 } 468 469 if (initrd_load()) 470 goto out; 471 472 /* wait for any asynchronous scanning to complete */ 473 if ((ROOT_DEV == 0) && root_wait) { 474 printk(KERN_INFO "Waiting for root device %s...\n", 475 saved_root_name); 476 while (driver_probe_done() != 0 || 477 (ROOT_DEV = name_to_dev_t(saved_root_name)) == 0) 478 msleep(100); 479 async_synchronize_full(); 480 } 481 482 is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR; 483 484 if (is_floppy && rd_doload && rd_load_disk(0)) 485 ROOT_DEV = Root_RAM0; 486 487 mount_root(); 488 out: 489 devtmpfs_mount("dev"); 490 sys_mount(".", "/", NULL, MS_MOVE, NULL); 491 sys_chroot((const char __user __force *)"."); 492 } 493