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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
26int __initdata rd_doload; /* 1 = load RAM disk, 0 = don't load */
27
28int root_mountflags = MS_RDONLY | MS_SILENT;
29static char * __initdata root_device_name;
30static char __initdata saved_root_name[64];
31static int __initdata root_wait;
32
33dev_t ROOT_DEV;
34
35static 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
42static int __init readonly(char *str)
43{
44 if (*str)
45 return 0;
46 root_mountflags |= MS_RDONLY;
47 return 1;
48}
49
50static 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 */
69static 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;
81no_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 */
96static 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
112done:
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
136dev_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
212fail:
213 return 0;
214done:
215 return res;
216}
217
218static 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
226static 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
236static char * __initdata root_mount_data;
237static int __init root_data_setup(char *str)
238{
239 root_mount_data = str;
240 return 1;
241}
242
243static char * __initdata root_fs_names;
244static int __init fs_names_setup(char *str)
245{
246 root_fs_names = str;
247 return 1;
248}
249
250static unsigned int __initdata root_delay;
251static 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
261static 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
288static 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
304void __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);
316retry:
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);
358out:
359 putname(fs_names);
360}
361
362#ifdef CONFIG_ROOT_NFS
363static 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)
376void __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
405void __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 */
437void __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();
489out:
490 devtmpfs_mount("dev");
491 sys_mount(".", "/", NULL, MS_MOVE, NULL);
492 sys_chroot((const char __user __force *)".");
493}
1/*
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
11#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>
20#include <linux/genhd.h>
21#include <linux/mount.h>
22#include <linux/device.h>
23#include <linux/init.h>
24#include <linux/fs.h>
25#include <linux/initrd.h>
26#include <linux/async.h>
27#include <linux/fs_struct.h>
28#include <linux/slab.h>
29#include <linux/ramfs.h>
30#include <linux/shmem_fs.h>
31
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
38int __initdata rd_doload; /* 1 = load RAM disk, 0 = don't load */
39
40int root_mountflags = MS_RDONLY | MS_SILENT;
41static char * __initdata root_device_name;
42static char __initdata saved_root_name[64];
43static int root_wait;
44
45dev_t ROOT_DEV;
46
47static 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
73#ifdef CONFIG_BLOCK
74struct uuidcmp {
75 const char *uuid;
76 int len;
77};
78
79/**
80 * match_dev_by_uuid - callback for finding a partition using its uuid
81 * @dev: device passed in by the caller
82 * @data: opaque pointer to the desired struct uuidcmp to match
83 *
84 * Returns 1 if the device matches, and 0 otherwise.
85 */
86static int match_dev_by_uuid(struct device *dev, const void *data)
87{
88 const struct uuidcmp *cmp = data;
89 struct hd_struct *part = dev_to_part(dev);
90
91 if (!part->info)
92 goto no_match;
93
94 if (strncasecmp(cmp->uuid, part->info->uuid, cmp->len))
95 goto no_match;
96
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
105 * @uuid_str: char array containing ascii UUID
106 *
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 *
111 * If @uuid_str is followed by a "/PARTNROFF=%d", then the number will be
112 * extracted and used as an offset from the partition identified by the UUID.
113 *
114 * Returns the matching dev_t on success or 0 on failure.
115 */
116static dev_t devt_from_partuuid(const char *uuid_str)
117{
118 dev_t res = 0;
119 struct uuidcmp cmp;
120 struct device *dev = NULL;
121 struct gendisk *disk;
122 struct hd_struct *part;
123 int offset = 0;
124 bool clear_root_wait = false;
125 char *slash;
126
127 cmp.uuid = uuid_str;
128
129 slash = strchr(uuid_str, '/');
130 /* Check for optional partition number offset attributes. */
131 if (slash) {
132 char c = 0;
133 /* Explicitly fail on poor PARTUUID syntax. */
134 if (sscanf(slash + 1,
135 "PARTNROFF=%d%c", &offset, &c) != 1) {
136 clear_root_wait = true;
137 goto done;
138 }
139 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;
147 }
148
149 dev = class_find_device(&block_class, NULL, &cmp,
150 &match_dev_by_uuid);
151 if (!dev)
152 goto done;
153
154 res = dev->devt;
155
156 /* 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);
170done:
171 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 }
178 return res;
179}
180#endif
181
182/*
183 * Convert a name into device number. We accept the following variants:
184 *
185 * 1) device number in hexadecimal represents itself
186 * 2) /dev/nfs represents Root_NFS (0xff)
187 * 3) /dev/<disk_name> represents the device number of disk
188 * 4) /dev/<disk_name><decimal> represents the device number
189 * of partition - device number of disk plus the partition number
190 * 5) /dev/<disk_name>p<decimal> - same as the above, that form is
191 * used when disk name of partitioned disk ends on a digit.
192 * 6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the
193 * unique id of a partition if the partition table provides it.
194 * The UUID may be either an EFI/GPT UUID, or refer to an MSDOS
195 * partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero-
196 * filled hex representation of the 32-bit "NT disk signature", and PP
197 * is a zero-filled hex representation of the 1-based partition number.
198 * 7) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation to
199 * a partition with a known unique id.
200 * 8) <major>:<minor> major and minor number of the device separated by
201 * a colon.
202 *
203 * If name doesn't have fall into the categories above, we return (0,0).
204 * block_class is used to check if something is a disk name. If the disk
205 * name contains slashes, the device name has them replaced with
206 * bangs.
207 */
208
209dev_t name_to_dev_t(char *name)
210{
211 char s[32];
212 char *p;
213 dev_t res = 0;
214 int part;
215
216#ifdef CONFIG_BLOCK
217 if (strncmp(name, "PARTUUID=", 9) == 0) {
218 name += 9;
219 res = devt_from_partuuid(name);
220 if (!res)
221 goto fail;
222 goto done;
223 }
224#endif
225
226 if (strncmp(name, "/dev/", 5) != 0) {
227 unsigned maj, min;
228
229 if (sscanf(name, "%u:%u", &maj, &min) == 2) {
230 res = MKDEV(maj, min);
231 if (maj != MAJOR(res) || min != MINOR(res))
232 goto fail;
233 } else {
234 res = new_decode_dev(simple_strtoul(name, &p, 16));
235 if (*p)
236 goto fail;
237 }
238 goto done;
239 }
240
241 name += 5;
242 res = Root_NFS;
243 if (strcmp(name, "nfs") == 0)
244 goto done;
245 res = Root_RAM0;
246 if (strcmp(name, "ram") == 0)
247 goto done;
248
249 if (strlen(name) > 31)
250 goto fail;
251 strcpy(s, name);
252 for (p = s; *p; p++)
253 if (*p == '/')
254 *p = '!';
255 res = blk_lookup_devt(s, 0);
256 if (res)
257 goto done;
258
259 /*
260 * try non-existent, but valid partition, which may only exist
261 * after revalidating the disk, like partitioned md devices
262 */
263 while (p > s && isdigit(p[-1]))
264 p--;
265 if (p == s || !*p || *p == '0')
266 goto fail;
267
268 /* try disk name without <part number> */
269 part = simple_strtoul(p, NULL, 10);
270 *p = '\0';
271 res = blk_lookup_devt(s, part);
272 if (res)
273 goto done;
274
275 /* try disk name without p<part number> */
276 if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
277 goto fail;
278 p[-1] = '\0';
279 res = blk_lookup_devt(s, part);
280 if (res)
281 goto done;
282
283fail:
284 return 0;
285done:
286 return res;
287}
288
289static int __init root_dev_setup(char *line)
290{
291 strlcpy(saved_root_name, line, sizeof(saved_root_name));
292 return 1;
293}
294
295__setup("root=", root_dev_setup);
296
297static int __init rootwait_setup(char *str)
298{
299 if (*str)
300 return 0;
301 root_wait = 1;
302 return 1;
303}
304
305__setup("rootwait", rootwait_setup);
306
307static char * __initdata root_mount_data;
308static int __init root_data_setup(char *str)
309{
310 root_mount_data = str;
311 return 1;
312}
313
314static char * __initdata root_fs_names;
315static int __init fs_names_setup(char *str)
316{
317 root_fs_names = str;
318 return 1;
319}
320
321static unsigned int __initdata root_delay;
322static int __init root_delay_setup(char *str)
323{
324 root_delay = simple_strtoul(str, NULL, 0);
325 return 1;
326}
327
328__setup("rootflags=", root_data_setup);
329__setup("rootfstype=", fs_names_setup);
330__setup("rootdelay=", root_delay_setup);
331
332static void __init get_fs_names(char *page)
333{
334 char *s = page;
335
336 if (root_fs_names) {
337 strcpy(page, root_fs_names);
338 while (*s++) {
339 if (s[-1] == ',')
340 s[-1] = '\0';
341 }
342 } else {
343 int len = get_filesystem_list(page);
344 char *p, *next;
345
346 page[len] = '\0';
347 for (p = page-1; p; p = next) {
348 next = strchr(++p, '\n');
349 if (*p++ != '\t')
350 continue;
351 while ((*s++ = *p++) != '\n')
352 ;
353 s[-1] = '\0';
354 }
355 }
356 *s = '\0';
357}
358
359static int __init do_mount_root(char *name, char *fs, int flags, void *data)
360{
361 struct super_block *s;
362 int err = sys_mount(name, "/root", fs, flags, data);
363 if (err)
364 return err;
365
366 sys_chdir("/root");
367 s = current->fs->pwd.dentry->d_sb;
368 ROOT_DEV = s->s_dev;
369 printk(KERN_INFO
370 "VFS: Mounted root (%s filesystem)%s on device %u:%u.\n",
371 s->s_type->name,
372 s->s_flags & MS_RDONLY ? " readonly" : "",
373 MAJOR(ROOT_DEV), MINOR(ROOT_DEV));
374 return 0;
375}
376
377void __init mount_block_root(char *name, int flags)
378{
379 struct page *page = alloc_page(GFP_KERNEL |
380 __GFP_NOTRACK_FALSE_POSITIVE);
381 char *fs_names = page_address(page);
382 char *p;
383#ifdef CONFIG_BLOCK
384 char b[BDEVNAME_SIZE];
385#else
386 const char *b = name;
387#endif
388
389 get_fs_names(fs_names);
390retry:
391 for (p = fs_names; *p; p += strlen(p)+1) {
392 int err = do_mount_root(name, p, flags, root_mount_data);
393 switch (err) {
394 case 0:
395 goto out;
396 case -EACCES:
397 flags |= MS_RDONLY;
398 goto retry;
399 case -EINVAL:
400 continue;
401 }
402 /*
403 * Allow the user to distinguish between failed sys_open
404 * and bad superblock on root device.
405 * and give them a list of the available devices
406 */
407#ifdef CONFIG_BLOCK
408 __bdevname(ROOT_DEV, b);
409#endif
410 printk("VFS: Cannot open root device \"%s\" or %s: error %d\n",
411 root_device_name, b, err);
412 printk("Please append a correct \"root=\" boot option; here are the available partitions:\n");
413
414 printk_all_partitions();
415#ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
416 printk("DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify "
417 "explicit textual name for \"root=\" boot option.\n");
418#endif
419 panic("VFS: Unable to mount root fs on %s", b);
420 }
421
422 printk("List of all partitions:\n");
423 printk_all_partitions();
424 printk("No filesystem could mount root, tried: ");
425 for (p = fs_names; *p; p += strlen(p)+1)
426 printk(" %s", p);
427 printk("\n");
428#ifdef CONFIG_BLOCK
429 __bdevname(ROOT_DEV, b);
430#endif
431 panic("VFS: Unable to mount root fs on %s", b);
432out:
433 put_page(page);
434}
435
436#ifdef CONFIG_ROOT_NFS
437
438#define NFSROOT_TIMEOUT_MIN 5
439#define NFSROOT_TIMEOUT_MAX 30
440#define NFSROOT_RETRY_MAX 5
441
442static int __init mount_nfs_root(void)
443{
444 char *root_dev, *root_data;
445 unsigned int timeout;
446 int try, err;
447
448 err = nfs_root_data(&root_dev, &root_data);
449 if (err != 0)
450 return 0;
451
452 /*
453 * The server or network may not be ready, so try several
454 * times. Stop after a few tries in case the client wants
455 * to fall back to other boot methods.
456 */
457 timeout = NFSROOT_TIMEOUT_MIN;
458 for (try = 1; ; try++) {
459 err = do_mount_root(root_dev, "nfs",
460 root_mountflags, root_data);
461 if (err == 0)
462 return 1;
463 if (try > NFSROOT_RETRY_MAX)
464 break;
465
466 /* Wait, in case the server refused us immediately */
467 ssleep(timeout);
468 timeout <<= 1;
469 if (timeout > NFSROOT_TIMEOUT_MAX)
470 timeout = NFSROOT_TIMEOUT_MAX;
471 }
472 return 0;
473}
474#endif
475
476#if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD)
477void __init change_floppy(char *fmt, ...)
478{
479 struct termios termios;
480 char buf[80];
481 char c;
482 int fd;
483 va_list args;
484 va_start(args, fmt);
485 vsprintf(buf, fmt, args);
486 va_end(args);
487 fd = sys_open("/dev/root", O_RDWR | O_NDELAY, 0);
488 if (fd >= 0) {
489 sys_ioctl(fd, FDEJECT, 0);
490 sys_close(fd);
491 }
492 printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf);
493 fd = sys_open("/dev/console", O_RDWR, 0);
494 if (fd >= 0) {
495 sys_ioctl(fd, TCGETS, (long)&termios);
496 termios.c_lflag &= ~ICANON;
497 sys_ioctl(fd, TCSETSF, (long)&termios);
498 sys_read(fd, &c, 1);
499 termios.c_lflag |= ICANON;
500 sys_ioctl(fd, TCSETSF, (long)&termios);
501 sys_close(fd);
502 }
503}
504#endif
505
506void __init mount_root(void)
507{
508#ifdef CONFIG_ROOT_NFS
509 if (ROOT_DEV == Root_NFS) {
510 if (mount_nfs_root())
511 return;
512
513 printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n");
514 ROOT_DEV = Root_FD0;
515 }
516#endif
517#ifdef CONFIG_BLK_DEV_FD
518 if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) {
519 /* rd_doload is 2 for a dual initrd/ramload setup */
520 if (rd_doload==2) {
521 if (rd_load_disk(1)) {
522 ROOT_DEV = Root_RAM1;
523 root_device_name = NULL;
524 }
525 } else
526 change_floppy("root floppy");
527 }
528#endif
529#ifdef CONFIG_BLOCK
530 create_dev("/dev/root", ROOT_DEV);
531 mount_block_root("/dev/root", root_mountflags);
532#endif
533}
534
535/*
536 * Prepare the namespace - decide what/where to mount, load ramdisks, etc.
537 */
538void __init prepare_namespace(void)
539{
540 int is_floppy;
541
542 if (root_delay) {
543 printk(KERN_INFO "Waiting %d sec before mounting root device...\n",
544 root_delay);
545 ssleep(root_delay);
546 }
547
548 /*
549 * wait for the known devices to complete their probing
550 *
551 * Note: this is a potential source of long boot delays.
552 * For example, it is not atypical to wait 5 seconds here
553 * for the touchpad of a laptop to initialize.
554 */
555 wait_for_device_probe();
556
557 md_run_setup();
558
559 if (saved_root_name[0]) {
560 root_device_name = saved_root_name;
561 if (!strncmp(root_device_name, "mtd", 3) ||
562 !strncmp(root_device_name, "ubi", 3)) {
563 mount_block_root(root_device_name, root_mountflags);
564 goto out;
565 }
566 ROOT_DEV = name_to_dev_t(root_device_name);
567 if (strncmp(root_device_name, "/dev/", 5) == 0)
568 root_device_name += 5;
569 }
570
571 if (initrd_load())
572 goto out;
573
574 /* wait for any asynchronous scanning to complete */
575 if ((ROOT_DEV == 0) && root_wait) {
576 printk(KERN_INFO "Waiting for root device %s...\n",
577 saved_root_name);
578 while (driver_probe_done() != 0 ||
579 (ROOT_DEV = name_to_dev_t(saved_root_name)) == 0)
580 msleep(100);
581 async_synchronize_full();
582 }
583
584 is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR;
585
586 if (is_floppy && rd_doload && rd_load_disk(0))
587 ROOT_DEV = Root_RAM0;
588
589 mount_root();
590out:
591 devtmpfs_mount("dev");
592 sys_mount(".", "/", NULL, MS_MOVE, NULL);
593 sys_chroot(".");
594}
595
596static bool is_tmpfs;
597static struct dentry *rootfs_mount(struct file_system_type *fs_type,
598 int flags, const char *dev_name, void *data)
599{
600 static unsigned long once;
601 void *fill = ramfs_fill_super;
602
603 if (test_and_set_bit(0, &once))
604 return ERR_PTR(-ENODEV);
605
606 if (IS_ENABLED(CONFIG_TMPFS) && is_tmpfs)
607 fill = shmem_fill_super;
608
609 return mount_nodev(fs_type, flags, data, fill);
610}
611
612static struct file_system_type rootfs_fs_type = {
613 .name = "rootfs",
614 .mount = rootfs_mount,
615 .kill_sb = kill_litter_super,
616};
617
618int __init init_rootfs(void)
619{
620 int err = register_filesystem(&rootfs_fs_type);
621
622 if (err)
623 return err;
624
625 if (IS_ENABLED(CONFIG_TMPFS) && !saved_root_name[0] &&
626 (!root_fs_names || strstr(root_fs_names, "tmpfs"))) {
627 err = shmem_init();
628 is_tmpfs = true;
629 } else {
630 err = init_ramfs_fs();
631 }
632
633 if (err)
634 unregister_filesystem(&rootfs_fs_type);
635
636 return err;
637}