blob: 816014c4627ee2f4adb7c8cf7ef53e6083de16fc [file] [log] [blame]
H Hartley Sweetenc67e5382012-05-31 16:26:10 -07001/*
2 * Many of the syscalls used in this file expect some of the arguments
3 * to be __user pointers not __kernel pointers. To limit the sparse
4 * noise, turn off sparse checking for this file.
5 */
6#ifdef __CHECKER__
7#undef __CHECKER__
8#warning "Sparse checking disabled for this file"
9#endif
10
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <linux/module.h>
12#include <linux/sched.h>
13#include <linux/ctype.h>
14#include <linux/fd.h>
15#include <linux/tty.h>
16#include <linux/suspend.h>
17#include <linux/root_dev.h>
18#include <linux/security.h>
19#include <linux/delay.h>
Dave Gilbertdd2a3452007-05-09 02:33:24 -070020#include <linux/genhd.h>
Andrew Mortond53d9f12005-07-12 13:58:07 -070021#include <linux/mount.h>
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -070022#include <linux/device.h>
Adrian Bunk46595392007-05-08 00:24:47 -070023#include <linux/init.h>
Adrian Bunk011e3fc2008-02-06 01:36:47 -080024#include <linux/fs.h>
Adrian Bunk82c82532008-07-25 01:45:29 -070025#include <linux/initrd.h>
Arjan van de Ven22a9d642009-01-07 08:45:46 -080026#include <linux/async.h>
Al Viro5ad4e532009-03-29 19:50:06 -040027#include <linux/fs_struct.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090028#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029
30#include <linux/nfs_fs.h>
31#include <linux/nfs_fs_sb.h>
32#include <linux/nfs_mount.h>
33
34#include "do_mounts.h"
35
Linus Torvalds1da177e2005-04-16 15:20:36 -070036int __initdata rd_doload; /* 1 = load RAM disk, 0 = don't load */
37
Theodore Ts'o9b04c992006-03-24 03:15:10 -080038int root_mountflags = MS_RDONLY | MS_SILENT;
Adrian Bunkf56f6d302008-07-25 19:46:25 -070039static char * __initdata root_device_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -070040static char __initdata saved_root_name[64];
Will Drewry79975f12011-11-02 13:38:59 -070041static int root_wait;
Linus Torvalds1da177e2005-04-16 15:20:36 -070042
Linus Torvalds1da177e2005-04-16 15:20:36 -070043dev_t ROOT_DEV;
44
Linus Torvalds1da177e2005-04-16 15:20:36 -070045static int __init load_ramdisk(char *str)
46{
47 rd_doload = simple_strtol(str,NULL,0) & 3;
48 return 1;
49}
50__setup("load_ramdisk=", load_ramdisk);
51
52static int __init readonly(char *str)
53{
54 if (*str)
55 return 0;
56 root_mountflags |= MS_RDONLY;
57 return 1;
58}
59
60static int __init readwrite(char *str)
61{
62 if (*str)
63 return 0;
64 root_mountflags &= ~MS_RDONLY;
65 return 1;
66}
67
68__setup("ro", readonly);
69__setup("rw", readwrite);
70
Jens Axboe6d0aed72010-09-17 10:00:46 +020071#ifdef CONFIG_BLOCK
Stephen Warren1ad7e892012-11-08 16:12:25 -080072struct uuidcmp {
73 const char *uuid;
74 int len;
75};
76
Will Drewryb5af9212010-08-31 15:47:07 -050077/**
78 * match_dev_by_uuid - callback for finding a partition using its uuid
79 * @dev: device passed in by the caller
Stephen Warren1ad7e892012-11-08 16:12:25 -080080 * @data: opaque pointer to the desired struct uuidcmp to match
Will Drewryb5af9212010-08-31 15:47:07 -050081 *
82 * Returns 1 if the device matches, and 0 otherwise.
83 */
Michał Mirosław9f3b7952013-02-01 20:40:17 +010084static int match_dev_by_uuid(struct device *dev, const void *data)
Will Drewryb5af9212010-08-31 15:47:07 -050085{
Michał Mirosław9f3b7952013-02-01 20:40:17 +010086 const struct uuidcmp *cmp = data;
Will Drewryb5af9212010-08-31 15:47:07 -050087 struct hd_struct *part = dev_to_part(dev);
88
89 if (!part->info)
90 goto no_match;
91
Stephen Warren1ad7e892012-11-08 16:12:25 -080092 if (strncasecmp(cmp->uuid, part->info->uuid, cmp->len))
93 goto no_match;
Will Drewryb5af9212010-08-31 15:47:07 -050094
95 return 1;
96no_match:
97 return 0;
98}
99
100
101/**
102 * devt_from_partuuid - looks up the dev_t of a partition by its UUID
Stephen Warren1ad7e892012-11-08 16:12:25 -0800103 * @uuid: char array containing ascii UUID
Will Drewryb5af9212010-08-31 15:47:07 -0500104 *
105 * The function will return the first partition which contains a matching
106 * UUID value in its partition_meta_info struct. This does not search
107 * by filesystem UUIDs.
108 *
Will Drewry79975f12011-11-02 13:38:59 -0700109 * If @uuid is followed by a "/PARTNROFF=%d", then the number will be
110 * extracted and used as an offset from the partition identified by the UUID.
111 *
Will Drewryb5af9212010-08-31 15:47:07 -0500112 * Returns the matching dev_t on success or 0 on failure.
113 */
Stephen Warren1ad7e892012-11-08 16:12:25 -0800114static dev_t devt_from_partuuid(const char *uuid_str)
Will Drewryb5af9212010-08-31 15:47:07 -0500115{
116 dev_t res = 0;
Stephen Warren1ad7e892012-11-08 16:12:25 -0800117 struct uuidcmp cmp;
Will Drewryb5af9212010-08-31 15:47:07 -0500118 struct device *dev = NULL;
Will Drewry79975f12011-11-02 13:38:59 -0700119 struct gendisk *disk;
120 struct hd_struct *part;
121 int offset = 0;
Stephen Warren283f8fc2012-11-08 16:12:27 -0800122 bool clear_root_wait = false;
123 char *slash;
Will Drewry79975f12011-11-02 13:38:59 -0700124
Stephen Warren1ad7e892012-11-08 16:12:25 -0800125 cmp.uuid = uuid_str;
Stephen Warren1ad7e892012-11-08 16:12:25 -0800126
Stephen Warren283f8fc2012-11-08 16:12:27 -0800127 slash = strchr(uuid_str, '/');
Will Drewry79975f12011-11-02 13:38:59 -0700128 /* Check for optional partition number offset attributes. */
Stephen Warren283f8fc2012-11-08 16:12:27 -0800129 if (slash) {
Will Drewry79975f12011-11-02 13:38:59 -0700130 char c = 0;
131 /* Explicitly fail on poor PARTUUID syntax. */
Stephen Warren283f8fc2012-11-08 16:12:27 -0800132 if (sscanf(slash + 1,
133 "PARTNROFF=%d%c", &offset, &c) != 1) {
134 clear_root_wait = true;
Will Drewry79975f12011-11-02 13:38:59 -0700135 goto done;
136 }
Stephen Warren283f8fc2012-11-08 16:12:27 -0800137 cmp.len = slash - uuid_str;
138 } else {
139 cmp.len = strlen(uuid_str);
140 }
141
142 if (!cmp.len) {
143 clear_root_wait = true;
144 goto done;
Will Drewry79975f12011-11-02 13:38:59 -0700145 }
Will Drewryb5af9212010-08-31 15:47:07 -0500146
Stephen Warren1ad7e892012-11-08 16:12:25 -0800147 dev = class_find_device(&block_class, NULL, &cmp,
148 &match_dev_by_uuid);
Will Drewryb5af9212010-08-31 15:47:07 -0500149 if (!dev)
150 goto done;
151
152 res = dev->devt;
Will Drewryb5af9212010-08-31 15:47:07 -0500153
Will Drewry79975f12011-11-02 13:38:59 -0700154 /* Attempt to find the partition by offset. */
155 if (!offset)
156 goto no_offset;
157
158 res = 0;
159 disk = part_to_disk(dev_to_part(dev));
160 part = disk_get_part(disk, dev_to_part(dev)->partno + offset);
161 if (part) {
162 res = part_devt(part);
163 put_device(part_to_dev(part));
164 }
165
166no_offset:
167 put_device(dev);
Will Drewryb5af9212010-08-31 15:47:07 -0500168done:
Stephen Warren283f8fc2012-11-08 16:12:27 -0800169 if (clear_root_wait) {
170 pr_err("VFS: PARTUUID= is invalid.\n"
171 "Expected PARTUUID=<valid-uuid-id>[/PARTNROFF=%%d]\n");
172 if (root_wait)
173 pr_err("Disabling rootwait; root= is invalid.\n");
174 root_wait = 0;
175 }
Will Drewryb5af9212010-08-31 15:47:07 -0500176 return res;
177}
Jens Axboe6d0aed72010-09-17 10:00:46 +0200178#endif
Will Drewryb5af9212010-08-31 15:47:07 -0500179
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180/*
181 * Convert a name into device number. We accept the following variants:
182 *
183 * 1) device number in hexadecimal represents itself
184 * 2) /dev/nfs represents Root_NFS (0xff)
185 * 3) /dev/<disk_name> represents the device number of disk
186 * 4) /dev/<disk_name><decimal> represents the device number
187 * of partition - device number of disk plus the partition number
188 * 5) /dev/<disk_name>p<decimal> - same as the above, that form is
189 * used when disk name of partitioned disk ends on a digit.
Will Drewryb5af9212010-08-31 15:47:07 -0500190 * 6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the
191 * unique id of a partition if the partition table provides it.
Stephen Warrend33b98f2012-11-08 16:12:28 -0800192 * The UUID may be either an EFI/GPT UUID, or refer to an MSDOS
193 * partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero-
194 * filled hex representation of the 32-bit "NT disk signature", and PP
195 * is a zero-filled hex representation of the 1-based partition number.
Will Drewry79975f12011-11-02 13:38:59 -0700196 * 7) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation to
197 * a partition with a known unique id.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 *
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200199 * If name doesn't have fall into the categories above, we return (0,0).
200 * block_class is used to check if something is a disk name. If the disk
201 * name contains slashes, the device name has them replaced with
202 * bangs.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203 */
204
205dev_t name_to_dev_t(char *name)
206{
207 char s[32];
208 char *p;
209 dev_t res = 0;
Kay Sievers30f2f0e2008-05-06 22:31:33 +0200210 int part;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211
Jens Axboe6d0aed72010-09-17 10:00:46 +0200212#ifdef CONFIG_BLOCK
Will Drewryb5af9212010-08-31 15:47:07 -0500213 if (strncmp(name, "PARTUUID=", 9) == 0) {
214 name += 9;
Will Drewryb5af9212010-08-31 15:47:07 -0500215 res = devt_from_partuuid(name);
216 if (!res)
217 goto fail;
218 goto done;
219 }
Jens Axboe6d0aed72010-09-17 10:00:46 +0200220#endif
Will Drewryb5af9212010-08-31 15:47:07 -0500221
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 if (strncmp(name, "/dev/", 5) != 0) {
223 unsigned maj, min;
224
225 if (sscanf(name, "%u:%u", &maj, &min) == 2) {
226 res = MKDEV(maj, min);
227 if (maj != MAJOR(res) || min != MINOR(res))
228 goto fail;
229 } else {
230 res = new_decode_dev(simple_strtoul(name, &p, 16));
231 if (*p)
232 goto fail;
233 }
234 goto done;
235 }
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200236
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 name += 5;
238 res = Root_NFS;
239 if (strcmp(name, "nfs") == 0)
240 goto done;
241 res = Root_RAM0;
242 if (strcmp(name, "ram") == 0)
243 goto done;
244
245 if (strlen(name) > 31)
246 goto fail;
247 strcpy(s, name);
248 for (p = s; *p; p++)
249 if (*p == '/')
250 *p = '!';
Kay Sievers30f2f0e2008-05-06 22:31:33 +0200251 res = blk_lookup_devt(s, 0);
252 if (res)
253 goto done;
254
255 /*
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300256 * try non-existent, but valid partition, which may only exist
Kay Sievers30f2f0e2008-05-06 22:31:33 +0200257 * after revalidating the disk, like partitioned md devices
258 */
259 while (p > s && isdigit(p[-1]))
260 p--;
261 if (p == s || !*p || *p == '0')
262 goto fail;
263
264 /* try disk name without <part number> */
265 part = simple_strtoul(p, NULL, 10);
266 *p = '\0';
267 res = blk_lookup_devt(s, part);
268 if (res)
269 goto done;
270
271 /* try disk name without p<part number> */
272 if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
273 goto fail;
274 p[-1] = '\0';
275 res = blk_lookup_devt(s, part);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 if (res)
277 goto done;
278
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279fail:
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200280 return 0;
281done:
282 return res;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283}
284
285static int __init root_dev_setup(char *line)
286{
287 strlcpy(saved_root_name, line, sizeof(saved_root_name));
288 return 1;
289}
290
291__setup("root=", root_dev_setup);
292
Pierre Ossmancc1ed752007-07-15 23:40:35 -0700293static int __init rootwait_setup(char *str)
294{
295 if (*str)
296 return 0;
297 root_wait = 1;
298 return 1;
299}
300
301__setup("rootwait", rootwait_setup);
302
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303static char * __initdata root_mount_data;
304static int __init root_data_setup(char *str)
305{
306 root_mount_data = str;
307 return 1;
308}
309
310static char * __initdata root_fs_names;
311static int __init fs_names_setup(char *str)
312{
313 root_fs_names = str;
314 return 1;
315}
316
317static unsigned int __initdata root_delay;
318static int __init root_delay_setup(char *str)
319{
320 root_delay = simple_strtoul(str, NULL, 0);
321 return 1;
322}
323
324__setup("rootflags=", root_data_setup);
325__setup("rootfstype=", fs_names_setup);
326__setup("rootdelay=", root_delay_setup);
327
328static void __init get_fs_names(char *page)
329{
330 char *s = page;
331
332 if (root_fs_names) {
333 strcpy(page, root_fs_names);
334 while (*s++) {
335 if (s[-1] == ',')
336 s[-1] = '\0';
337 }
338 } else {
339 int len = get_filesystem_list(page);
340 char *p, *next;
341
342 page[len] = '\0';
343 for (p = page-1; p; p = next) {
344 next = strchr(++p, '\n');
345 if (*p++ != '\t')
346 continue;
347 while ((*s++ = *p++) != '\n')
348 ;
349 s[-1] = '\0';
350 }
351 }
352 *s = '\0';
353}
354
355static int __init do_mount_root(char *name, char *fs, int flags, void *data)
356{
Al Virod8c95842011-12-07 18:16:57 -0500357 struct super_block *s;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358 int err = sys_mount(name, "/root", fs, flags, data);
359 if (err)
360 return err;
361
H Hartley Sweetenc67e5382012-05-31 16:26:10 -0700362 sys_chdir("/root");
Al Virod8c95842011-12-07 18:16:57 -0500363 s = current->fs->pwd.dentry->d_sb;
364 ROOT_DEV = s->s_dev;
Mandeep Singh Baines80cdc6d2011-03-22 16:33:54 -0700365 printk(KERN_INFO
366 "VFS: Mounted root (%s filesystem)%s on device %u:%u.\n",
Al Virod8c95842011-12-07 18:16:57 -0500367 s->s_type->name,
368 s->s_flags & MS_RDONLY ? " readonly" : "",
369 MAJOR(ROOT_DEV), MINOR(ROOT_DEV));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370 return 0;
371}
372
373void __init mount_block_root(char *name, int flags)
374{
Jeff Laytona608ca22012-10-10 15:25:26 -0400375 struct page *page = alloc_page(GFP_KERNEL |
376 __GFP_NOTRACK_FALSE_POSITIVE);
377 char *fs_names = page_address(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378 char *p;
David Howells93614012006-09-30 20:45:40 +0200379#ifdef CONFIG_BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380 char b[BDEVNAME_SIZE];
David Howells93614012006-09-30 20:45:40 +0200381#else
382 const char *b = name;
383#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384
385 get_fs_names(fs_names);
386retry:
387 for (p = fs_names; *p; p += strlen(p)+1) {
388 int err = do_mount_root(name, p, flags, root_mount_data);
389 switch (err) {
390 case 0:
391 goto out;
392 case -EACCES:
393 flags |= MS_RDONLY;
394 goto retry;
395 case -EINVAL:
396 continue;
397 }
398 /*
399 * Allow the user to distinguish between failed sys_open
400 * and bad superblock on root device.
Dave Gilbertdd2a3452007-05-09 02:33:24 -0700401 * and give them a list of the available devices
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402 */
David Howells93614012006-09-30 20:45:40 +0200403#ifdef CONFIG_BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404 __bdevname(ROOT_DEV, b);
David Howells93614012006-09-30 20:45:40 +0200405#endif
Bernhard Walle0e0cb892012-03-23 15:02:28 -0700406 printk("VFS: Cannot open root device \"%s\" or %s: error %d\n",
407 root_device_name, b, err);
Dave Gilbertdd2a3452007-05-09 02:33:24 -0700408 printk("Please append a correct \"root=\" boot option; here are the available partitions:\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409
Dave Gilbertdd2a3452007-05-09 02:33:24 -0700410 printk_all_partitions();
Tejun Heo55dc7db2008-09-01 13:44:35 +0200411#ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
412 printk("DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify "
413 "explicit textual name for \"root=\" boot option.\n");
414#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415 panic("VFS: Unable to mount root fs on %s", b);
416 }
Andy Whitcroftbe6e028b2006-05-15 09:44:29 -0700417
Dave Gilbertdd2a3452007-05-09 02:33:24 -0700418 printk("List of all partitions:\n");
419 printk_all_partitions();
Andy Whitcroftbe6e028b2006-05-15 09:44:29 -0700420 printk("No filesystem could mount root, tried: ");
421 for (p = fs_names; *p; p += strlen(p)+1)
422 printk(" %s", p);
423 printk("\n");
David Howells93614012006-09-30 20:45:40 +0200424#ifdef CONFIG_BLOCK
425 __bdevname(ROOT_DEV, b);
426#endif
427 panic("VFS: Unable to mount root fs on %s", b);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428out:
Jeff Laytona608ca22012-10-10 15:25:26 -0400429 put_page(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430}
431
432#ifdef CONFIG_ROOT_NFS
Chuck Lever43717c72011-12-05 15:40:30 -0500433
434#define NFSROOT_TIMEOUT_MIN 5
435#define NFSROOT_TIMEOUT_MAX 30
436#define NFSROOT_RETRY_MAX 5
437
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438static int __init mount_nfs_root(void)
439{
Chuck Lever56463e52010-09-17 10:54:37 -0400440 char *root_dev, *root_data;
Chuck Lever43717c72011-12-05 15:40:30 -0500441 unsigned int timeout;
442 int try, err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443
Chuck Lever43717c72011-12-05 15:40:30 -0500444 err = nfs_root_data(&root_dev, &root_data);
445 if (err != 0)
Chuck Lever56463e52010-09-17 10:54:37 -0400446 return 0;
Chuck Lever43717c72011-12-05 15:40:30 -0500447
448 /*
449 * The server or network may not be ready, so try several
450 * times. Stop after a few tries in case the client wants
451 * to fall back to other boot methods.
452 */
453 timeout = NFSROOT_TIMEOUT_MIN;
454 for (try = 1; ; try++) {
455 err = do_mount_root(root_dev, "nfs",
456 root_mountflags, root_data);
457 if (err == 0)
458 return 1;
459 if (try > NFSROOT_RETRY_MAX)
460 break;
461
462 /* Wait, in case the server refused us immediately */
463 ssleep(timeout);
464 timeout <<= 1;
465 if (timeout > NFSROOT_TIMEOUT_MAX)
466 timeout = NFSROOT_TIMEOUT_MAX;
467 }
468 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469}
470#endif
471
472#if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD)
473void __init change_floppy(char *fmt, ...)
474{
475 struct termios termios;
476 char buf[80];
477 char c;
478 int fd;
479 va_list args;
480 va_start(args, fmt);
481 vsprintf(buf, fmt, args);
482 va_end(args);
483 fd = sys_open("/dev/root", O_RDWR | O_NDELAY, 0);
484 if (fd >= 0) {
485 sys_ioctl(fd, FDEJECT, 0);
486 sys_close(fd);
487 }
488 printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf);
489 fd = sys_open("/dev/console", O_RDWR, 0);
490 if (fd >= 0) {
491 sys_ioctl(fd, TCGETS, (long)&termios);
492 termios.c_lflag &= ~ICANON;
493 sys_ioctl(fd, TCSETSF, (long)&termios);
494 sys_read(fd, &c, 1);
495 termios.c_lflag |= ICANON;
496 sys_ioctl(fd, TCSETSF, (long)&termios);
497 sys_close(fd);
498 }
499}
500#endif
501
502void __init mount_root(void)
503{
504#ifdef CONFIG_ROOT_NFS
Sasha Levin377485f2012-05-05 17:06:35 +0200505 if (ROOT_DEV == Root_NFS) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 if (mount_nfs_root())
507 return;
508
509 printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n");
510 ROOT_DEV = Root_FD0;
511 }
512#endif
513#ifdef CONFIG_BLK_DEV_FD
514 if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) {
515 /* rd_doload is 2 for a dual initrd/ramload setup */
516 if (rd_doload==2) {
517 if (rd_load_disk(1)) {
518 ROOT_DEV = Root_RAM1;
519 root_device_name = NULL;
520 }
521 } else
522 change_floppy("root floppy");
523 }
524#endif
David Howells93614012006-09-30 20:45:40 +0200525#ifdef CONFIG_BLOCK
Greg Kroah-Hartmanbdaf8522005-06-20 21:15:16 -0700526 create_dev("/dev/root", ROOT_DEV);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527 mount_block_root("/dev/root", root_mountflags);
David Howells93614012006-09-30 20:45:40 +0200528#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529}
530
531/*
532 * Prepare the namespace - decide what/where to mount, load ramdisks, etc.
533 */
534void __init prepare_namespace(void)
535{
536 int is_floppy;
537
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538 if (root_delay) {
Toralf Försterca75b4d82013-07-03 15:05:38 -0700539 printk(KERN_INFO "Waiting %d sec before mounting root device...\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540 root_delay);
541 ssleep(root_delay);
542 }
543
Arjan van de Ven216773a2009-02-14 01:59:06 +0100544 /*
545 * wait for the known devices to complete their probing
546 *
547 * Note: this is a potential source of long boot delays.
548 * For example, it is not atypical to wait 5 seconds here
549 * for the touchpad of a laptop to initialize.
550 */
551 wait_for_device_probe();
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700552
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553 md_run_setup();
554
555 if (saved_root_name[0]) {
556 root_device_name = saved_root_name;
Adrian Hunter2d62f482008-01-31 17:25:00 +0200557 if (!strncmp(root_device_name, "mtd", 3) ||
558 !strncmp(root_device_name, "ubi", 3)) {
Joern Engele9482b42006-05-30 14:25:46 +0200559 mount_block_root(root_device_name, root_mountflags);
560 goto out;
561 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562 ROOT_DEV = name_to_dev_t(root_device_name);
563 if (strncmp(root_device_name, "/dev/", 5) == 0)
564 root_device_name += 5;
565 }
566
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567 if (initrd_load())
568 goto out;
569
Pierre Ossmancc1ed752007-07-15 23:40:35 -0700570 /* wait for any asynchronous scanning to complete */
571 if ((ROOT_DEV == 0) && root_wait) {
572 printk(KERN_INFO "Waiting for root device %s...\n",
573 saved_root_name);
574 while (driver_probe_done() != 0 ||
575 (ROOT_DEV = name_to_dev_t(saved_root_name)) == 0)
576 msleep(100);
Arjan van de Ven216773a2009-02-14 01:59:06 +0100577 async_synchronize_full();
Pierre Ossmancc1ed752007-07-15 23:40:35 -0700578 }
579
580 is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR;
581
Linus Torvalds1da177e2005-04-16 15:20:36 -0700582 if (is_floppy && rd_doload && rd_load_disk(0))
583 ROOT_DEV = Root_RAM0;
584
585 mount_root();
586out:
Kay Sievers2b2af542009-04-30 15:23:42 +0200587 devtmpfs_mount("dev");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588 sys_mount(".", "/", NULL, MS_MOVE, NULL);
H Hartley Sweetenc67e5382012-05-31 16:26:10 -0700589 sys_chroot(".");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590}