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Source at commit b13e7eb172b6f08e5fc22da162bdde5fcde201b5 created 11 years 11 months ago. By Maarten ter Huurne, fbcon: Add 6x10 font | |
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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 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: min 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 | * If @uuid is followed by a "/PARTNROFF=%d", then the number will be |
95 | * extracted and used as an offset from the partition identified by the UUID. |
96 | * |
97 | * Returns the matching dev_t on success or 0 on failure. |
98 | */ |
99 | static dev_t devt_from_partuuid(char *uuid_str) |
100 | { |
101 | dev_t res = 0; |
102 | struct device *dev = NULL; |
103 | u8 uuid[16]; |
104 | struct gendisk *disk; |
105 | struct hd_struct *part; |
106 | int offset = 0; |
107 | |
108 | if (strlen(uuid_str) < 36) |
109 | goto done; |
110 | |
111 | /* Check for optional partition number offset attributes. */ |
112 | if (uuid_str[36]) { |
113 | char c = 0; |
114 | /* Explicitly fail on poor PARTUUID syntax. */ |
115 | if (sscanf(&uuid_str[36], |
116 | "/PARTNROFF=%d%c", &offset, &c) != 1) { |
117 | printk(KERN_ERR "VFS: PARTUUID= is invalid.\n" |
118 | "Expected PARTUUID=<valid-uuid-id>[/PARTNROFF=%%d]\n"); |
119 | if (root_wait) |
120 | printk(KERN_ERR |
121 | "Disabling rootwait; root= is invalid.\n"); |
122 | root_wait = 0; |
123 | goto done; |
124 | } |
125 | } |
126 | |
127 | /* Pack the requested UUID in the expected format. */ |
128 | part_pack_uuid(uuid_str, uuid); |
129 | |
130 | dev = class_find_device(&block_class, NULL, uuid, &match_dev_by_uuid); |
131 | if (!dev) |
132 | goto done; |
133 | |
134 | res = dev->devt; |
135 | |
136 | /* Attempt to find the partition by offset. */ |
137 | if (!offset) |
138 | goto no_offset; |
139 | |
140 | res = 0; |
141 | disk = part_to_disk(dev_to_part(dev)); |
142 | part = disk_get_part(disk, dev_to_part(dev)->partno + offset); |
143 | if (part) { |
144 | res = part_devt(part); |
145 | put_device(part_to_dev(part)); |
146 | } |
147 | |
148 | no_offset: |
149 | put_device(dev); |
150 | done: |
151 | return res; |
152 | } |
153 | #endif |
154 | |
155 | /* |
156 | * Convert a name into device number. We accept the following variants: |
157 | * |
158 | * 1) device number in hexadecimal represents itself |
159 | * 2) /dev/nfs represents Root_NFS (0xff) |
160 | * 3) /dev/<disk_name> represents the device number of disk |
161 | * 4) /dev/<disk_name><decimal> represents the device number |
162 | * of partition - device number of disk plus the partition number |
163 | * 5) /dev/<disk_name>p<decimal> - same as the above, that form is |
164 | * used when disk name of partitioned disk ends on a digit. |
165 | * 6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the |
166 | * unique id of a partition if the partition table provides it. |
167 | * 7) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation to |
168 | * a partition with a known unique id. |
169 | * |
170 | * If name doesn't have fall into the categories above, we return (0,0). |
171 | * block_class is used to check if something is a disk name. If the disk |
172 | * name contains slashes, the device name has them replaced with |
173 | * bangs. |
174 | */ |
175 | |
176 | dev_t name_to_dev_t(char *name) |
177 | { |
178 | char s[32]; |
179 | char *p; |
180 | dev_t res = 0; |
181 | int part; |
182 | |
183 | #ifdef CONFIG_BLOCK |
184 | if (strncmp(name, "PARTUUID=", 9) == 0) { |
185 | name += 9; |
186 | res = devt_from_partuuid(name); |
187 | if (!res) |
188 | goto fail; |
189 | goto done; |
190 | } |
191 | #endif |
192 | |
193 | if (strncmp(name, "/dev/", 5) != 0) { |
194 | unsigned maj, min; |
195 | |
196 | if (sscanf(name, "%u:%u", &maj, &min) == 2) { |
197 | res = MKDEV(maj, min); |
198 | if (maj != MAJOR(res) || min != MINOR(res)) |
199 | goto fail; |
200 | } else { |
201 | res = new_decode_dev(simple_strtoul(name, &p, 16)); |
202 | if (*p) |
203 | goto fail; |
204 | } |
205 | goto done; |
206 | } |
207 | |
208 | name += 5; |
209 | res = Root_NFS; |
210 | if (strcmp(name, "nfs") == 0) |
211 | goto done; |
212 | res = Root_RAM0; |
213 | if (strcmp(name, "ram") == 0) |
214 | goto done; |
215 | |
216 | if (strlen(name) > 31) |
217 | goto fail; |
218 | strcpy(s, name); |
219 | for (p = s; *p; p++) |
220 | if (*p == '/') |
221 | *p = '!'; |
222 | res = blk_lookup_devt(s, 0); |
223 | if (res) |
224 | goto done; |
225 | |
226 | /* |
227 | * try non-existent, but valid partition, which may only exist |
228 | * after revalidating the disk, like partitioned md devices |
229 | */ |
230 | while (p > s && isdigit(p[-1])) |
231 | p--; |
232 | if (p == s || !*p || *p == '0') |
233 | goto fail; |
234 | |
235 | /* try disk name without <part number> */ |
236 | part = simple_strtoul(p, NULL, 10); |
237 | *p = '\0'; |
238 | res = blk_lookup_devt(s, part); |
239 | if (res) |
240 | goto done; |
241 | |
242 | /* try disk name without p<part number> */ |
243 | if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p') |
244 | goto fail; |
245 | p[-1] = '\0'; |
246 | res = blk_lookup_devt(s, part); |
247 | if (res) |
248 | goto done; |
249 | |
250 | fail: |
251 | return 0; |
252 | done: |
253 | return res; |
254 | } |
255 | |
256 | static int __init root_dev_setup(char *line) |
257 | { |
258 | strlcpy(saved_root_name, line, sizeof(saved_root_name)); |
259 | return 1; |
260 | } |
261 | |
262 | __setup("root=", root_dev_setup); |
263 | |
264 | static int __init rootwait_setup(char *str) |
265 | { |
266 | if (*str) |
267 | return 0; |
268 | root_wait = 1; |
269 | return 1; |
270 | } |
271 | |
272 | __setup("rootwait", rootwait_setup); |
273 | |
274 | static char * __initdata root_mount_data; |
275 | static int __init root_data_setup(char *str) |
276 | { |
277 | root_mount_data = str; |
278 | return 1; |
279 | } |
280 | |
281 | static char * __initdata root_fs_names; |
282 | static int __init fs_names_setup(char *str) |
283 | { |
284 | root_fs_names = str; |
285 | return 1; |
286 | } |
287 | |
288 | static unsigned int __initdata root_delay; |
289 | static int __init root_delay_setup(char *str) |
290 | { |
291 | root_delay = simple_strtoul(str, NULL, 0); |
292 | return 1; |
293 | } |
294 | |
295 | __setup("rootflags=", root_data_setup); |
296 | __setup("rootfstype=", fs_names_setup); |
297 | __setup("rootdelay=", root_delay_setup); |
298 | |
299 | static void __init get_fs_names(char *page) |
300 | { |
301 | char *s = page; |
302 | |
303 | if (root_fs_names) { |
304 | strcpy(page, root_fs_names); |
305 | while (*s++) { |
306 | if (s[-1] == ',') |
307 | s[-1] = '\0'; |
308 | } |
309 | } else { |
310 | int len = get_filesystem_list(page); |
311 | char *p, *next; |
312 | |
313 | page[len] = '\0'; |
314 | for (p = page-1; p; p = next) { |
315 | next = strchr(++p, '\n'); |
316 | if (*p++ != '\t') |
317 | continue; |
318 | while ((*s++ = *p++) != '\n') |
319 | ; |
320 | s[-1] = '\0'; |
321 | } |
322 | } |
323 | *s = '\0'; |
324 | } |
325 | |
326 | static int __init do_mount_root(char *name, char *fs, int flags, void *data) |
327 | { |
328 | struct super_block *s; |
329 | int err = sys_mount(name, "/root", fs, flags, data); |
330 | if (err) |
331 | return err; |
332 | |
333 | sys_chdir((const char __user __force *)"/root"); |
334 | s = current->fs->pwd.dentry->d_sb; |
335 | ROOT_DEV = s->s_dev; |
336 | printk(KERN_INFO |
337 | "VFS: Mounted root (%s filesystem)%s on device %u:%u.\n", |
338 | s->s_type->name, |
339 | s->s_flags & MS_RDONLY ? " readonly" : "", |
340 | MAJOR(ROOT_DEV), MINOR(ROOT_DEV)); |
341 | return 0; |
342 | } |
343 | |
344 | void __init mount_block_root(char *name, int flags) |
345 | { |
346 | char *fs_names = __getname_gfp(GFP_KERNEL |
347 | | __GFP_NOTRACK_FALSE_POSITIVE); |
348 | char *p; |
349 | #ifdef CONFIG_BLOCK |
350 | char b[BDEVNAME_SIZE]; |
351 | #else |
352 | const char *b = name; |
353 | #endif |
354 | |
355 | get_fs_names(fs_names); |
356 | retry: |
357 | for (p = fs_names; *p; p += strlen(p)+1) { |
358 | int err = do_mount_root(name, p, flags, root_mount_data); |
359 | switch (err) { |
360 | case 0: |
361 | goto out; |
362 | case -EACCES: |
363 | flags |= MS_RDONLY; |
364 | goto retry; |
365 | case -EINVAL: |
366 | continue; |
367 | } |
368 | /* |
369 | * Allow the user to distinguish between failed sys_open |
370 | * and bad superblock on root device. |
371 | * and give them a list of the available devices |
372 | */ |
373 | #ifdef CONFIG_BLOCK |
374 | __bdevname(ROOT_DEV, b); |
375 | #endif |
376 | printk("VFS: Cannot open root device \"%s\" or %s\n", |
377 | root_device_name, b); |
378 | printk("Please append a correct \"root=\" boot option; here are the available partitions:\n"); |
379 | |
380 | printk_all_partitions(); |
381 | #ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT |
382 | printk("DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify " |
383 | "explicit textual name for \"root=\" boot option.\n"); |
384 | #endif |
385 | panic("VFS: Unable to mount root fs on %s", b); |
386 | } |
387 | |
388 | printk("List of all partitions:\n"); |
389 | printk_all_partitions(); |
390 | printk("No filesystem could mount root, tried: "); |
391 | for (p = fs_names; *p; p += strlen(p)+1) |
392 | printk(" %s", p); |
393 | printk("\n"); |
394 | #ifdef CONFIG_BLOCK |
395 | __bdevname(ROOT_DEV, b); |
396 | #endif |
397 | panic("VFS: Unable to mount root fs on %s", b); |
398 | out: |
399 | putname(fs_names); |
400 | } |
401 | |
402 | #ifdef CONFIG_ROOT_NFS |
403 | |
404 | #define NFSROOT_TIMEOUT_MIN 5 |
405 | #define NFSROOT_TIMEOUT_MAX 30 |
406 | #define NFSROOT_RETRY_MAX 5 |
407 | |
408 | static int __init mount_nfs_root(void) |
409 | { |
410 | char *root_dev, *root_data; |
411 | unsigned int timeout; |
412 | int try, err; |
413 | |
414 | err = nfs_root_data(&root_dev, &root_data); |
415 | if (err != 0) |
416 | return 0; |
417 | |
418 | /* |
419 | * The server or network may not be ready, so try several |
420 | * times. Stop after a few tries in case the client wants |
421 | * to fall back to other boot methods. |
422 | */ |
423 | timeout = NFSROOT_TIMEOUT_MIN; |
424 | for (try = 1; ; try++) { |
425 | err = do_mount_root(root_dev, "nfs", |
426 | root_mountflags, root_data); |
427 | if (err == 0) |
428 | return 1; |
429 | if (try > NFSROOT_RETRY_MAX) |
430 | break; |
431 | |
432 | /* Wait, in case the server refused us immediately */ |
433 | ssleep(timeout); |
434 | timeout <<= 1; |
435 | if (timeout > NFSROOT_TIMEOUT_MAX) |
436 | timeout = NFSROOT_TIMEOUT_MAX; |
437 | } |
438 | return 0; |
439 | } |
440 | #endif |
441 | |
442 | #if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD) |
443 | void __init change_floppy(char *fmt, ...) |
444 | { |
445 | struct termios termios; |
446 | char buf[80]; |
447 | char c; |
448 | int fd; |
449 | va_list args; |
450 | va_start(args, fmt); |
451 | vsprintf(buf, fmt, args); |
452 | va_end(args); |
453 | fd = sys_open("/dev/root", O_RDWR | O_NDELAY, 0); |
454 | if (fd >= 0) { |
455 | sys_ioctl(fd, FDEJECT, 0); |
456 | sys_close(fd); |
457 | } |
458 | printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf); |
459 | fd = sys_open("/dev/console", O_RDWR, 0); |
460 | if (fd >= 0) { |
461 | sys_ioctl(fd, TCGETS, (long)&termios); |
462 | termios.c_lflag &= ~ICANON; |
463 | sys_ioctl(fd, TCSETSF, (long)&termios); |
464 | sys_read(fd, &c, 1); |
465 | termios.c_lflag |= ICANON; |
466 | sys_ioctl(fd, TCSETSF, (long)&termios); |
467 | sys_close(fd); |
468 | } |
469 | } |
470 | #endif |
471 | |
472 | void __init mount_root(void) |
473 | { |
474 | #ifdef CONFIG_ROOT_NFS |
475 | if (MAJOR(ROOT_DEV) == UNNAMED_MAJOR) { |
476 | if (mount_nfs_root()) |
477 | return; |
478 | |
479 | printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n"); |
480 | ROOT_DEV = Root_FD0; |
481 | } |
482 | #endif |
483 | #ifdef CONFIG_BLK_DEV_FD |
484 | if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) { |
485 | /* rd_doload is 2 for a dual initrd/ramload setup */ |
486 | if (rd_doload==2) { |
487 | if (rd_load_disk(1)) { |
488 | ROOT_DEV = Root_RAM1; |
489 | root_device_name = NULL; |
490 | } |
491 | } else |
492 | change_floppy("root floppy"); |
493 | } |
494 | #endif |
495 | #ifdef CONFIG_BLOCK |
496 | create_dev("/dev/root", ROOT_DEV); |
497 | mount_block_root("/dev/root", root_mountflags); |
498 | #endif |
499 | } |
500 | |
501 | /* |
502 | * Prepare the namespace - decide what/where to mount, load ramdisks, etc. |
503 | */ |
504 | void __init prepare_namespace(void) |
505 | { |
506 | int is_floppy; |
507 | |
508 | if (root_delay) { |
509 | printk(KERN_INFO "Waiting %dsec before mounting root device...\n", |
510 | root_delay); |
511 | ssleep(root_delay); |
512 | } |
513 | |
514 | /* |
515 | * wait for the known devices to complete their probing |
516 | * |
517 | * Note: this is a potential source of long boot delays. |
518 | * For example, it is not atypical to wait 5 seconds here |
519 | * for the touchpad of a laptop to initialize. |
520 | */ |
521 | wait_for_device_probe(); |
522 | |
523 | md_run_setup(); |
524 | |
525 | if (saved_root_name[0]) { |
526 | root_device_name = saved_root_name; |
527 | if (!strncmp(root_device_name, "mtd", 3) || |
528 | !strncmp(root_device_name, "ubi", 3)) { |
529 | mount_block_root(root_device_name, root_mountflags); |
530 | goto out; |
531 | } |
532 | ROOT_DEV = name_to_dev_t(root_device_name); |
533 | if (strncmp(root_device_name, "/dev/", 5) == 0) |
534 | root_device_name += 5; |
535 | } |
536 | |
537 | if (initrd_load()) |
538 | goto out; |
539 | |
540 | /* wait for any asynchronous scanning to complete */ |
541 | if ((ROOT_DEV == 0) && root_wait) { |
542 | printk(KERN_INFO "Waiting for root device %s...\n", |
543 | saved_root_name); |
544 | while (driver_probe_done() != 0 || |
545 | (ROOT_DEV = name_to_dev_t(saved_root_name)) == 0) |
546 | msleep(100); |
547 | async_synchronize_full(); |
548 | } |
549 | |
550 | is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR; |
551 | |
552 | if (is_floppy && rd_doload && rd_load_disk(0)) |
553 | ROOT_DEV = Root_RAM0; |
554 | |
555 | mount_root(); |
556 | out: |
557 | devtmpfs_mount("dev"); |
558 | sys_mount(".", "/", NULL, MS_MOVE, NULL); |
559 | sys_chroot((const char __user __force *)"."); |
560 | } |
561 |
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