Root/
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 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9