blob: dea5de95c2dd23771f44e58ada2d9b1dbfa1c5df [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>
Rob Landley57f150a2013-09-11 14:26:10 -070029#include <linux/ramfs.h>
Rob Landley16203a72013-09-11 14:26:12 -070030#include <linux/shmem_fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
32#include <linux/nfs_fs.h>
33#include <linux/nfs_fs_sb.h>
34#include <linux/nfs_mount.h>
35
36#include "do_mounts.h"
37
Linus Torvalds1da177e2005-04-16 15:20:36 -070038int __initdata rd_doload; /* 1 = load RAM disk, 0 = don't load */
39
Theodore Ts'o9b04c992006-03-24 03:15:10 -080040int root_mountflags = MS_RDONLY | MS_SILENT;
Adrian Bunkf56f6d302008-07-25 19:46:25 -070041static char * __initdata root_device_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -070042static char __initdata saved_root_name[64];
Will Drewry79975f12011-11-02 13:38:59 -070043static int root_wait;
Linus Torvalds1da177e2005-04-16 15:20:36 -070044
Linus Torvalds1da177e2005-04-16 15:20:36 -070045dev_t ROOT_DEV;
46
Linus Torvalds1da177e2005-04-16 15:20:36 -070047static int __init load_ramdisk(char *str)
48{
49 rd_doload = simple_strtol(str,NULL,0) & 3;
50 return 1;
51}
52__setup("load_ramdisk=", load_ramdisk);
53
54static int __init readonly(char *str)
55{
56 if (*str)
57 return 0;
58 root_mountflags |= MS_RDONLY;
59 return 1;
60}
61
62static int __init readwrite(char *str)
63{
64 if (*str)
65 return 0;
66 root_mountflags &= ~MS_RDONLY;
67 return 1;
68}
69
70__setup("ro", readonly);
71__setup("rw", readwrite);
72
Jens Axboe6d0aed72010-09-17 10:00:46 +020073#ifdef CONFIG_BLOCK
Stephen Warren1ad7e892012-11-08 16:12:25 -080074struct uuidcmp {
75 const char *uuid;
76 int len;
77};
78
Will Drewryb5af9212010-08-31 15:47:07 -050079/**
80 * match_dev_by_uuid - callback for finding a partition using its uuid
81 * @dev: device passed in by the caller
Stephen Warren1ad7e892012-11-08 16:12:25 -080082 * @data: opaque pointer to the desired struct uuidcmp to match
Will Drewryb5af9212010-08-31 15:47:07 -050083 *
84 * Returns 1 if the device matches, and 0 otherwise.
85 */
Michał Mirosław9f3b7952013-02-01 20:40:17 +010086static int match_dev_by_uuid(struct device *dev, const void *data)
Will Drewryb5af9212010-08-31 15:47:07 -050087{
Michał Mirosław9f3b7952013-02-01 20:40:17 +010088 const struct uuidcmp *cmp = data;
Will Drewryb5af9212010-08-31 15:47:07 -050089 struct hd_struct *part = dev_to_part(dev);
90
91 if (!part->info)
92 goto no_match;
93
Stephen Warren1ad7e892012-11-08 16:12:25 -080094 if (strncasecmp(cmp->uuid, part->info->uuid, cmp->len))
95 goto no_match;
Will Drewryb5af9212010-08-31 15:47:07 -050096
97 return 1;
98no_match:
99 return 0;
100}
101
102
103/**
104 * devt_from_partuuid - looks up the dev_t of a partition by its UUID
chishanmingshena68b3102014-04-03 14:49:35 -0700105 * @uuid_str: char array containing ascii UUID
Will Drewryb5af9212010-08-31 15:47:07 -0500106 *
107 * The function will return the first partition which contains a matching
108 * UUID value in its partition_meta_info struct. This does not search
109 * by filesystem UUIDs.
110 *
chishanmingshena68b3102014-04-03 14:49:35 -0700111 * If @uuid_str is followed by a "/PARTNROFF=%d", then the number will be
Will Drewry79975f12011-11-02 13:38:59 -0700112 * extracted and used as an offset from the partition identified by the UUID.
113 *
Will Drewryb5af9212010-08-31 15:47:07 -0500114 * Returns the matching dev_t on success or 0 on failure.
115 */
Stephen Warren1ad7e892012-11-08 16:12:25 -0800116static dev_t devt_from_partuuid(const char *uuid_str)
Will Drewryb5af9212010-08-31 15:47:07 -0500117{
118 dev_t res = 0;
Stephen Warren1ad7e892012-11-08 16:12:25 -0800119 struct uuidcmp cmp;
Will Drewryb5af9212010-08-31 15:47:07 -0500120 struct device *dev = NULL;
Will Drewry79975f12011-11-02 13:38:59 -0700121 struct gendisk *disk;
122 struct hd_struct *part;
123 int offset = 0;
Stephen Warren283f8fc2012-11-08 16:12:27 -0800124 bool clear_root_wait = false;
125 char *slash;
Will Drewry79975f12011-11-02 13:38:59 -0700126
Stephen Warren1ad7e892012-11-08 16:12:25 -0800127 cmp.uuid = uuid_str;
Stephen Warren1ad7e892012-11-08 16:12:25 -0800128
Stephen Warren283f8fc2012-11-08 16:12:27 -0800129 slash = strchr(uuid_str, '/');
Will Drewry79975f12011-11-02 13:38:59 -0700130 /* Check for optional partition number offset attributes. */
Stephen Warren283f8fc2012-11-08 16:12:27 -0800131 if (slash) {
Will Drewry79975f12011-11-02 13:38:59 -0700132 char c = 0;
133 /* Explicitly fail on poor PARTUUID syntax. */
Stephen Warren283f8fc2012-11-08 16:12:27 -0800134 if (sscanf(slash + 1,
135 "PARTNROFF=%d%c", &offset, &c) != 1) {
136 clear_root_wait = true;
Will Drewry79975f12011-11-02 13:38:59 -0700137 goto done;
138 }
Stephen Warren283f8fc2012-11-08 16:12:27 -0800139 cmp.len = slash - uuid_str;
140 } else {
141 cmp.len = strlen(uuid_str);
142 }
143
144 if (!cmp.len) {
145 clear_root_wait = true;
146 goto done;
Will Drewry79975f12011-11-02 13:38:59 -0700147 }
Will Drewryb5af9212010-08-31 15:47:07 -0500148
Stephen Warren1ad7e892012-11-08 16:12:25 -0800149 dev = class_find_device(&block_class, NULL, &cmp,
150 &match_dev_by_uuid);
Will Drewryb5af9212010-08-31 15:47:07 -0500151 if (!dev)
152 goto done;
153
154 res = dev->devt;
Will Drewryb5af9212010-08-31 15:47:07 -0500155
Will Drewry79975f12011-11-02 13:38:59 -0700156 /* Attempt to find the partition by offset. */
157 if (!offset)
158 goto no_offset;
159
160 res = 0;
161 disk = part_to_disk(dev_to_part(dev));
162 part = disk_get_part(disk, dev_to_part(dev)->partno + offset);
163 if (part) {
164 res = part_devt(part);
165 put_device(part_to_dev(part));
166 }
167
168no_offset:
169 put_device(dev);
Will Drewryb5af9212010-08-31 15:47:07 -0500170done:
Stephen Warren283f8fc2012-11-08 16:12:27 -0800171 if (clear_root_wait) {
172 pr_err("VFS: PARTUUID= is invalid.\n"
173 "Expected PARTUUID=<valid-uuid-id>[/PARTNROFF=%%d]\n");
174 if (root_wait)
175 pr_err("Disabling rootwait; root= is invalid.\n");
176 root_wait = 0;
177 }
Will Drewryb5af9212010-08-31 15:47:07 -0500178 return res;
179}
Jens Axboe6d0aed72010-09-17 10:00:46 +0200180#endif
Will Drewryb5af9212010-08-31 15:47:07 -0500181
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182/*
183 * Convert a name into device number. We accept the following variants:
184 *
Pavel Machek0bf37ae2014-08-26 13:49:35 +0200185 * 1) <hex_major><hex_minor> device number in hexadecimal represents itself
186 * no leading 0x, for example b302.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700187 * 2) /dev/nfs represents Root_NFS (0xff)
188 * 3) /dev/<disk_name> represents the device number of disk
189 * 4) /dev/<disk_name><decimal> represents the device number
190 * of partition - device number of disk plus the partition number
191 * 5) /dev/<disk_name>p<decimal> - same as the above, that form is
192 * used when disk name of partitioned disk ends on a digit.
Will Drewryb5af9212010-08-31 15:47:07 -0500193 * 6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the
194 * unique id of a partition if the partition table provides it.
Stephen Warrend33b98f2012-11-08 16:12:28 -0800195 * The UUID may be either an EFI/GPT UUID, or refer to an MSDOS
196 * partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero-
197 * filled hex representation of the 32-bit "NT disk signature", and PP
198 * is a zero-filled hex representation of the 1-based partition number.
Will Drewry79975f12011-11-02 13:38:59 -0700199 * 7) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation to
200 * a partition with a known unique id.
Sebastian Capella6c251612013-11-12 15:08:39 -0800201 * 8) <major>:<minor> major and minor number of the device separated by
202 * a colon.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203 *
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200204 * If name doesn't have fall into the categories above, we return (0,0).
205 * block_class is used to check if something is a disk name. If the disk
206 * name contains slashes, the device name has them replaced with
207 * bangs.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 */
209
Dan Ehrenberge6e20a72015-02-10 15:20:49 -0800210dev_t name_to_dev_t(const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211{
212 char s[32];
213 char *p;
214 dev_t res = 0;
Kay Sievers30f2f0e2008-05-06 22:31:33 +0200215 int part;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216
Jens Axboe6d0aed72010-09-17 10:00:46 +0200217#ifdef CONFIG_BLOCK
Will Drewryb5af9212010-08-31 15:47:07 -0500218 if (strncmp(name, "PARTUUID=", 9) == 0) {
219 name += 9;
Will Drewryb5af9212010-08-31 15:47:07 -0500220 res = devt_from_partuuid(name);
221 if (!res)
222 goto fail;
223 goto done;
224 }
Jens Axboe6d0aed72010-09-17 10:00:46 +0200225#endif
Will Drewryb5af9212010-08-31 15:47:07 -0500226
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 if (strncmp(name, "/dev/", 5) != 0) {
Chen Yucb31ef42015-05-03 22:35:05 +0800228 unsigned maj, min, offset;
Dan Ehrenberg283e7ad2015-02-10 15:20:50 -0800229 char dummy;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230
Chen Yucb31ef42015-05-03 22:35:05 +0800231 if ((sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2) ||
232 (sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset, &dummy) == 3)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 res = MKDEV(maj, min);
234 if (maj != MAJOR(res) || min != MINOR(res))
235 goto fail;
236 } else {
237 res = new_decode_dev(simple_strtoul(name, &p, 16));
238 if (*p)
239 goto fail;
240 }
241 goto done;
242 }
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200243
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 name += 5;
245 res = Root_NFS;
246 if (strcmp(name, "nfs") == 0)
247 goto done;
248 res = Root_RAM0;
249 if (strcmp(name, "ram") == 0)
250 goto done;
251
252 if (strlen(name) > 31)
253 goto fail;
254 strcpy(s, name);
255 for (p = s; *p; p++)
256 if (*p == '/')
257 *p = '!';
Kay Sievers30f2f0e2008-05-06 22:31:33 +0200258 res = blk_lookup_devt(s, 0);
259 if (res)
260 goto done;
261
262 /*
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300263 * try non-existent, but valid partition, which may only exist
Kay Sievers30f2f0e2008-05-06 22:31:33 +0200264 * after revalidating the disk, like partitioned md devices
265 */
266 while (p > s && isdigit(p[-1]))
267 p--;
268 if (p == s || !*p || *p == '0')
269 goto fail;
270
271 /* try disk name without <part number> */
272 part = simple_strtoul(p, NULL, 10);
273 *p = '\0';
274 res = blk_lookup_devt(s, part);
275 if (res)
276 goto done;
277
278 /* try disk name without p<part number> */
279 if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
280 goto fail;
281 p[-1] = '\0';
282 res = blk_lookup_devt(s, part);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283 if (res)
284 goto done;
285
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286fail:
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200287 return 0;
288done:
289 return res;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290}
Dan Ehrenberge6e20a72015-02-10 15:20:49 -0800291EXPORT_SYMBOL_GPL(name_to_dev_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292
293static int __init root_dev_setup(char *line)
294{
295 strlcpy(saved_root_name, line, sizeof(saved_root_name));
296 return 1;
297}
298
299__setup("root=", root_dev_setup);
300
Pierre Ossmancc1ed752007-07-15 23:40:35 -0700301static int __init rootwait_setup(char *str)
302{
303 if (*str)
304 return 0;
305 root_wait = 1;
306 return 1;
307}
308
309__setup("rootwait", rootwait_setup);
310
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311static char * __initdata root_mount_data;
312static int __init root_data_setup(char *str)
313{
314 root_mount_data = str;
315 return 1;
316}
317
318static char * __initdata root_fs_names;
319static int __init fs_names_setup(char *str)
320{
321 root_fs_names = str;
322 return 1;
323}
324
325static unsigned int __initdata root_delay;
326static int __init root_delay_setup(char *str)
327{
328 root_delay = simple_strtoul(str, NULL, 0);
329 return 1;
330}
331
332__setup("rootflags=", root_data_setup);
333__setup("rootfstype=", fs_names_setup);
334__setup("rootdelay=", root_delay_setup);
335
336static void __init get_fs_names(char *page)
337{
338 char *s = page;
339
340 if (root_fs_names) {
341 strcpy(page, root_fs_names);
342 while (*s++) {
343 if (s[-1] == ',')
344 s[-1] = '\0';
345 }
346 } else {
347 int len = get_filesystem_list(page);
348 char *p, *next;
349
350 page[len] = '\0';
351 for (p = page-1; p; p = next) {
352 next = strchr(++p, '\n');
353 if (*p++ != '\t')
354 continue;
355 while ((*s++ = *p++) != '\n')
356 ;
357 s[-1] = '\0';
358 }
359 }
360 *s = '\0';
361}
362
363static int __init do_mount_root(char *name, char *fs, int flags, void *data)
364{
Al Virod8c95842011-12-07 18:16:57 -0500365 struct super_block *s;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366 int err = sys_mount(name, "/root", fs, flags, data);
367 if (err)
368 return err;
369
H Hartley Sweetenc67e5382012-05-31 16:26:10 -0700370 sys_chdir("/root");
Al Virod8c95842011-12-07 18:16:57 -0500371 s = current->fs->pwd.dentry->d_sb;
372 ROOT_DEV = s->s_dev;
Mandeep Singh Baines80cdc6d2011-03-22 16:33:54 -0700373 printk(KERN_INFO
374 "VFS: Mounted root (%s filesystem)%s on device %u:%u.\n",
Al Virod8c95842011-12-07 18:16:57 -0500375 s->s_type->name,
376 s->s_flags & MS_RDONLY ? " readonly" : "",
377 MAJOR(ROOT_DEV), MINOR(ROOT_DEV));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378 return 0;
379}
380
381void __init mount_block_root(char *name, int flags)
382{
Jeff Laytona608ca22012-10-10 15:25:26 -0400383 struct page *page = alloc_page(GFP_KERNEL |
384 __GFP_NOTRACK_FALSE_POSITIVE);
385 char *fs_names = page_address(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386 char *p;
David Howells93614012006-09-30 20:45:40 +0200387#ifdef CONFIG_BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 char b[BDEVNAME_SIZE];
David Howells93614012006-09-30 20:45:40 +0200389#else
390 const char *b = name;
391#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392
393 get_fs_names(fs_names);
394retry:
395 for (p = fs_names; *p; p += strlen(p)+1) {
396 int err = do_mount_root(name, p, flags, root_mount_data);
397 switch (err) {
398 case 0:
399 goto out;
400 case -EACCES:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401 case -EINVAL:
402 continue;
403 }
404 /*
405 * Allow the user to distinguish between failed sys_open
406 * and bad superblock on root device.
Dave Gilbertdd2a3452007-05-09 02:33:24 -0700407 * and give them a list of the available devices
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408 */
David Howells93614012006-09-30 20:45:40 +0200409#ifdef CONFIG_BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 __bdevname(ROOT_DEV, b);
David Howells93614012006-09-30 20:45:40 +0200411#endif
Bernhard Walle0e0cb892012-03-23 15:02:28 -0700412 printk("VFS: Cannot open root device \"%s\" or %s: error %d\n",
413 root_device_name, b, err);
Dave Gilbertdd2a3452007-05-09 02:33:24 -0700414 printk("Please append a correct \"root=\" boot option; here are the available partitions:\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415
Dave Gilbertdd2a3452007-05-09 02:33:24 -0700416 printk_all_partitions();
Tejun Heo55dc7db2008-09-01 13:44:35 +0200417#ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
418 printk("DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify "
419 "explicit textual name for \"root=\" boot option.\n");
420#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421 panic("VFS: Unable to mount root fs on %s", b);
422 }
Miklos Szeredi109759332014-11-20 16:08:59 +0100423 if (!(flags & MS_RDONLY)) {
424 flags |= MS_RDONLY;
425 goto retry;
426 }
Andy Whitcroftbe6e028b2006-05-15 09:44:29 -0700427
Dave Gilbertdd2a3452007-05-09 02:33:24 -0700428 printk("List of all partitions:\n");
429 printk_all_partitions();
Andy Whitcroftbe6e028b2006-05-15 09:44:29 -0700430 printk("No filesystem could mount root, tried: ");
431 for (p = fs_names; *p; p += strlen(p)+1)
432 printk(" %s", p);
433 printk("\n");
David Howells93614012006-09-30 20:45:40 +0200434#ifdef CONFIG_BLOCK
435 __bdevname(ROOT_DEV, b);
436#endif
437 panic("VFS: Unable to mount root fs on %s", b);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438out:
Jeff Laytona608ca22012-10-10 15:25:26 -0400439 put_page(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440}
441
442#ifdef CONFIG_ROOT_NFS
Chuck Lever43717c72011-12-05 15:40:30 -0500443
444#define NFSROOT_TIMEOUT_MIN 5
445#define NFSROOT_TIMEOUT_MAX 30
446#define NFSROOT_RETRY_MAX 5
447
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448static int __init mount_nfs_root(void)
449{
Chuck Lever56463e52010-09-17 10:54:37 -0400450 char *root_dev, *root_data;
Chuck Lever43717c72011-12-05 15:40:30 -0500451 unsigned int timeout;
452 int try, err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453
Chuck Lever43717c72011-12-05 15:40:30 -0500454 err = nfs_root_data(&root_dev, &root_data);
455 if (err != 0)
Chuck Lever56463e52010-09-17 10:54:37 -0400456 return 0;
Chuck Lever43717c72011-12-05 15:40:30 -0500457
458 /*
459 * The server or network may not be ready, so try several
460 * times. Stop after a few tries in case the client wants
461 * to fall back to other boot methods.
462 */
463 timeout = NFSROOT_TIMEOUT_MIN;
464 for (try = 1; ; try++) {
465 err = do_mount_root(root_dev, "nfs",
466 root_mountflags, root_data);
467 if (err == 0)
468 return 1;
469 if (try > NFSROOT_RETRY_MAX)
470 break;
471
472 /* Wait, in case the server refused us immediately */
473 ssleep(timeout);
474 timeout <<= 1;
475 if (timeout > NFSROOT_TIMEOUT_MAX)
476 timeout = NFSROOT_TIMEOUT_MAX;
477 }
478 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479}
480#endif
481
482#if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD)
483void __init change_floppy(char *fmt, ...)
484{
485 struct termios termios;
486 char buf[80];
487 char c;
488 int fd;
489 va_list args;
490 va_start(args, fmt);
491 vsprintf(buf, fmt, args);
492 va_end(args);
493 fd = sys_open("/dev/root", O_RDWR | O_NDELAY, 0);
494 if (fd >= 0) {
495 sys_ioctl(fd, FDEJECT, 0);
496 sys_close(fd);
497 }
498 printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf);
499 fd = sys_open("/dev/console", O_RDWR, 0);
500 if (fd >= 0) {
501 sys_ioctl(fd, TCGETS, (long)&termios);
502 termios.c_lflag &= ~ICANON;
503 sys_ioctl(fd, TCSETSF, (long)&termios);
504 sys_read(fd, &c, 1);
505 termios.c_lflag |= ICANON;
506 sys_ioctl(fd, TCSETSF, (long)&termios);
507 sys_close(fd);
508 }
509}
510#endif
511
512void __init mount_root(void)
513{
514#ifdef CONFIG_ROOT_NFS
Sasha Levin377485f62012-05-05 17:06:35 +0200515 if (ROOT_DEV == Root_NFS) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516 if (mount_nfs_root())
517 return;
518
519 printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n");
520 ROOT_DEV = Root_FD0;
521 }
522#endif
523#ifdef CONFIG_BLK_DEV_FD
524 if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) {
525 /* rd_doload is 2 for a dual initrd/ramload setup */
526 if (rd_doload==2) {
527 if (rd_load_disk(1)) {
528 ROOT_DEV = Root_RAM1;
529 root_device_name = NULL;
530 }
531 } else
532 change_floppy("root floppy");
533 }
534#endif
David Howells93614012006-09-30 20:45:40 +0200535#ifdef CONFIG_BLOCK
Vishnu Pratap Singhc69e3c32015-06-25 15:03:37 -0700536 {
537 int err = create_dev("/dev/root", ROOT_DEV);
538
539 if (err < 0)
540 pr_emerg("Failed to create /dev/root: %d\n", err);
541 mount_block_root("/dev/root", root_mountflags);
542 }
David Howells93614012006-09-30 20:45:40 +0200543#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544}
545
546/*
547 * Prepare the namespace - decide what/where to mount, load ramdisks, etc.
548 */
549void __init prepare_namespace(void)
550{
551 int is_floppy;
552
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553 if (root_delay) {
Toralf Försterca75b4d82013-07-03 15:05:38 -0700554 printk(KERN_INFO "Waiting %d sec before mounting root device...\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 root_delay);
556 ssleep(root_delay);
557 }
558
Arjan van de Ven216773a2009-02-14 01:59:06 +0100559 /*
560 * wait for the known devices to complete their probing
561 *
562 * Note: this is a potential source of long boot delays.
563 * For example, it is not atypical to wait 5 seconds here
564 * for the touchpad of a laptop to initialize.
565 */
566 wait_for_device_probe();
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700567
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568 md_run_setup();
569
570 if (saved_root_name[0]) {
571 root_device_name = saved_root_name;
Adrian Hunter2d62f482008-01-31 17:25:00 +0200572 if (!strncmp(root_device_name, "mtd", 3) ||
573 !strncmp(root_device_name, "ubi", 3)) {
Joern Engele9482b42006-05-30 14:25:46 +0200574 mount_block_root(root_device_name, root_mountflags);
575 goto out;
576 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577 ROOT_DEV = name_to_dev_t(root_device_name);
578 if (strncmp(root_device_name, "/dev/", 5) == 0)
579 root_device_name += 5;
580 }
581
Linus Torvalds1da177e2005-04-16 15:20:36 -0700582 if (initrd_load())
583 goto out;
584
Pierre Ossmancc1ed752007-07-15 23:40:35 -0700585 /* wait for any asynchronous scanning to complete */
586 if ((ROOT_DEV == 0) && root_wait) {
587 printk(KERN_INFO "Waiting for root device %s...\n",
588 saved_root_name);
589 while (driver_probe_done() != 0 ||
590 (ROOT_DEV = name_to_dev_t(saved_root_name)) == 0)
591 msleep(100);
Arjan van de Ven216773a2009-02-14 01:59:06 +0100592 async_synchronize_full();
Pierre Ossmancc1ed752007-07-15 23:40:35 -0700593 }
594
595 is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR;
596
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 if (is_floppy && rd_doload && rd_load_disk(0))
598 ROOT_DEV = Root_RAM0;
599
600 mount_root();
601out:
Kay Sievers2b2af542009-04-30 15:23:42 +0200602 devtmpfs_mount("dev");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603 sys_mount(".", "/", NULL, MS_MOVE, NULL);
H Hartley Sweetenc67e5382012-05-31 16:26:10 -0700604 sys_chroot(".");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605}
Rob Landley57f150a2013-09-11 14:26:10 -0700606
Rob Landley6e19ede2013-09-11 14:26:13 -0700607static bool is_tmpfs;
Rob Landley57f150a2013-09-11 14:26:10 -0700608static struct dentry *rootfs_mount(struct file_system_type *fs_type,
609 int flags, const char *dev_name, void *data)
610{
611 static unsigned long once;
Rob Landley6e19ede2013-09-11 14:26:13 -0700612 void *fill = ramfs_fill_super;
Rob Landley57f150a2013-09-11 14:26:10 -0700613
614 if (test_and_set_bit(0, &once))
615 return ERR_PTR(-ENODEV);
616
Rob Landley6e19ede2013-09-11 14:26:13 -0700617 if (IS_ENABLED(CONFIG_TMPFS) && is_tmpfs)
618 fill = shmem_fill_super;
619
620 return mount_nodev(fs_type, flags, data, fill);
Rob Landley57f150a2013-09-11 14:26:10 -0700621}
622
623static struct file_system_type rootfs_fs_type = {
624 .name = "rootfs",
625 .mount = rootfs_mount,
626 .kill_sb = kill_litter_super,
627};
628
629int __init init_rootfs(void)
630{
631 int err = register_filesystem(&rootfs_fs_type);
632
633 if (err)
634 return err;
635
Rob Landley6e19ede2013-09-11 14:26:13 -0700636 if (IS_ENABLED(CONFIG_TMPFS) && !saved_root_name[0] &&
637 (!root_fs_names || strstr(root_fs_names, "tmpfs"))) {
Rob Landley16203a72013-09-11 14:26:12 -0700638 err = shmem_init();
Rob Landley6e19ede2013-09-11 14:26:13 -0700639 is_tmpfs = true;
640 } else {
Rob Landley16203a72013-09-11 14:26:12 -0700641 err = init_ramfs_fs();
Rob Landley6e19ede2013-09-11 14:26:13 -0700642 }
Rob Landley16203a72013-09-11 14:26:12 -0700643
Rob Landley57f150a2013-09-11 14:26:10 -0700644 if (err)
645 unregister_filesystem(&rootfs_fs_type);
646
647 return err;
648}