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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;
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
81
82
83
84
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
105
106
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108
109
110
111
112
113
114
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
131 if (slash) {
132 char c = 0;
133
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
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
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206
207dev_t name_to_dev_t(char *name)
208{
209 char s[32];
210 char *p;
211 dev_t res = 0;
212 int part;
213
214#ifdef CONFIG_BLOCK
215 if (strncmp(name, "PARTUUID=", 9) == 0) {
216 name += 9;
217 res = devt_from_partuuid(name);
218 if (!res)
219 goto fail;
220 goto done;
221 }
222#endif
223
224 if (strncmp(name, "/dev/", 5) != 0) {
225 unsigned maj, min;
226
227 if (sscanf(name, "%u:%u", &maj, &min) == 2) {
228 res = MKDEV(maj, min);
229 if (maj != MAJOR(res) || min != MINOR(res))
230 goto fail;
231 } else {
232 res = new_decode_dev(simple_strtoul(name, &p, 16));
233 if (*p)
234 goto fail;
235 }
236 goto done;
237 }
238
239 name += 5;
240 res = Root_NFS;
241 if (strcmp(name, "nfs") == 0)
242 goto done;
243 res = Root_RAM0;
244 if (strcmp(name, "ram") == 0)
245 goto done;
246
247 if (strlen(name) > 31)
248 goto fail;
249 strcpy(s, name);
250 for (p = s; *p; p++)
251 if (*p == '/')
252 *p = '!';
253 res = blk_lookup_devt(s, 0);
254 if (res)
255 goto done;
256
257
258
259
260
261 while (p > s && isdigit(p[-1]))
262 p--;
263 if (p == s || !*p || *p == '0')
264 goto fail;
265
266
267 part = simple_strtoul(p, NULL, 10);
268 *p = '\0';
269 res = blk_lookup_devt(s, part);
270 if (res)
271 goto done;
272
273
274 if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
275 goto fail;
276 p[-1] = '\0';
277 res = blk_lookup_devt(s, part);
278 if (res)
279 goto done;
280
281fail:
282 return 0;
283done:
284 return res;
285}
286
287static int __init root_dev_setup(char *line)
288{
289 strlcpy(saved_root_name, line, sizeof(saved_root_name));
290 return 1;
291}
292
293__setup("root=", root_dev_setup);
294
295static int __init rootwait_setup(char *str)
296{
297 if (*str)
298 return 0;
299 root_wait = 1;
300 return 1;
301}
302
303__setup("rootwait", rootwait_setup);
304
305static char * __initdata root_mount_data;
306static int __init root_data_setup(char *str)
307{
308 root_mount_data = str;
309 return 1;
310}
311
312static char * __initdata root_fs_names;
313static int __init fs_names_setup(char *str)
314{
315 root_fs_names = str;
316 return 1;
317}
318
319static unsigned int __initdata root_delay;
320static int __init root_delay_setup(char *str)
321{
322 root_delay = simple_strtoul(str, NULL, 0);
323 return 1;
324}
325
326__setup("rootflags=", root_data_setup);
327__setup("rootfstype=", fs_names_setup);
328__setup("rootdelay=", root_delay_setup);
329
330static void __init get_fs_names(char *page)
331{
332 char *s = page;
333
334 if (root_fs_names) {
335 strcpy(page, root_fs_names);
336 while (*s++) {
337 if (s[-1] == ',')
338 s[-1] = '\0';
339 }
340 } else {
341 int len = get_filesystem_list(page);
342 char *p, *next;
343
344 page[len] = '\0';
345 for (p = page-1; p; p = next) {
346 next = strchr(++p, '\n');
347 if (*p++ != '\t')
348 continue;
349 while ((*s++ = *p++) != '\n')
350 ;
351 s[-1] = '\0';
352 }
353 }
354 *s = '\0';
355}
356
357static int __init do_mount_root(char *name, char *fs, int flags, void *data)
358{
359 struct super_block *s;
360 int err = sys_mount(name, "/root", fs, flags, data);
361 if (err)
362 return err;
363
364 sys_chdir("/root");
365 s = current->fs->pwd.dentry->d_sb;
366 ROOT_DEV = s->s_dev;
367 printk(KERN_INFO
368 "VFS: Mounted root (%s filesystem)%s on device %u:%u.\n",
369 s->s_type->name,
370 s->s_flags & MS_RDONLY ? " readonly" : "",
371 MAJOR(ROOT_DEV), MINOR(ROOT_DEV));
372 return 0;
373}
374
375void __init mount_block_root(char *name, int flags)
376{
377 struct page *page = alloc_page(GFP_KERNEL |
378 __GFP_NOTRACK_FALSE_POSITIVE);
379 char *fs_names = page_address(page);
380 char *p;
381#ifdef CONFIG_BLOCK
382 char b[BDEVNAME_SIZE];
383#else
384 const char *b = name;
385#endif
386
387 get_fs_names(fs_names);
388retry:
389 for (p = fs_names; *p; p += strlen(p)+1) {
390 int err = do_mount_root(name, p, flags, root_mount_data);
391 switch (err) {
392 case 0:
393 goto out;
394 case -EACCES:
395 flags |= MS_RDONLY;
396 goto retry;
397 case -EINVAL:
398 continue;
399 }
400
401
402
403
404
405#ifdef CONFIG_BLOCK
406 __bdevname(ROOT_DEV, b);
407#endif
408 printk("VFS: Cannot open root device \"%s\" or %s: error %d\n",
409 root_device_name, b, err);
410 printk("Please append a correct \"root=\" boot option; here are the available partitions:\n");
411
412 printk_all_partitions();
413#ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
414 printk("DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify "
415 "explicit textual name for \"root=\" boot option.\n");
416#endif
417 panic("VFS: Unable to mount root fs on %s", b);
418 }
419
420 printk("List of all partitions:\n");
421 printk_all_partitions();
422 printk("No filesystem could mount root, tried: ");
423 for (p = fs_names; *p; p += strlen(p)+1)
424 printk(" %s", p);
425 printk("\n");
426#ifdef CONFIG_BLOCK
427 __bdevname(ROOT_DEV, b);
428#endif
429 panic("VFS: Unable to mount root fs on %s", b);
430out:
431 put_page(page);
432}
433
434#ifdef CONFIG_ROOT_NFS
435
436#define NFSROOT_TIMEOUT_MIN 5
437#define NFSROOT_TIMEOUT_MAX 30
438#define NFSROOT_RETRY_MAX 5
439
440static int __init mount_nfs_root(void)
441{
442 char *root_dev, *root_data;
443 unsigned int timeout;
444 int try, err;
445
446 err = nfs_root_data(&root_dev, &root_data);
447 if (err != 0)
448 return 0;
449
450
451
452
453
454
455 timeout = NFSROOT_TIMEOUT_MIN;
456 for (try = 1; ; try++) {
457 err = do_mount_root(root_dev, "nfs",
458 root_mountflags, root_data);
459 if (err == 0)
460 return 1;
461 if (try > NFSROOT_RETRY_MAX)
462 break;
463
464
465 ssleep(timeout);
466 timeout <<= 1;
467 if (timeout > NFSROOT_TIMEOUT_MAX)
468 timeout = NFSROOT_TIMEOUT_MAX;
469 }
470 return 0;
471}
472#endif
473
474#if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD)
475void __init change_floppy(char *fmt, ...)
476{
477 struct termios termios;
478 char buf[80];
479 char c;
480 int fd;
481 va_list args;
482 va_start(args, fmt);
483 vsprintf(buf, fmt, args);
484 va_end(args);
485 fd = sys_open("/dev/root", O_RDWR | O_NDELAY, 0);
486 if (fd >= 0) {
487 sys_ioctl(fd, FDEJECT, 0);
488 sys_close(fd);
489 }
490 printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf);
491 fd = sys_open("/dev/console", O_RDWR, 0);
492 if (fd >= 0) {
493 sys_ioctl(fd, TCGETS, (long)&termios);
494 termios.c_lflag &= ~ICANON;
495 sys_ioctl(fd, TCSETSF, (long)&termios);
496 sys_read(fd, &c, 1);
497 termios.c_lflag |= ICANON;
498 sys_ioctl(fd, TCSETSF, (long)&termios);
499 sys_close(fd);
500 }
501}
502#endif
503
504void __init mount_root(void)
505{
506#ifdef CONFIG_ROOT_NFS
507 if (ROOT_DEV == Root_NFS) {
508 if (mount_nfs_root())
509 return;
510
511 printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n");
512 ROOT_DEV = Root_FD0;
513 }
514#endif
515#ifdef CONFIG_BLK_DEV_FD
516 if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) {
517
518 if (rd_doload==2) {
519 if (rd_load_disk(1)) {
520 ROOT_DEV = Root_RAM1;
521 root_device_name = NULL;
522 }
523 } else
524 change_floppy("root floppy");
525 }
526#endif
527#ifdef CONFIG_BLOCK
528 create_dev("/dev/root", ROOT_DEV);
529 mount_block_root("/dev/root", root_mountflags);
530#endif
531}
532
533
534
535
536void __init prepare_namespace(void)
537{
538 int is_floppy;
539
540 if (root_delay) {
541 printk(KERN_INFO "Waiting %d sec before mounting root device...\n",
542 root_delay);
543 ssleep(root_delay);
544 }
545
546
547
548
549
550
551
552
553 wait_for_device_probe();
554
555 md_run_setup();
556
557 if (saved_root_name[0]) {
558 root_device_name = saved_root_name;
559 if (!strncmp(root_device_name, "mtd", 3) ||
560 !strncmp(root_device_name, "ubi", 3)) {
561 mount_block_root(root_device_name, root_mountflags);
562 goto out;
563 }
564 ROOT_DEV = name_to_dev_t(root_device_name);
565 if (strncmp(root_device_name, "/dev/", 5) == 0)
566 root_device_name += 5;
567 }
568
569 if (initrd_load())
570 goto out;
571
572
573 if ((ROOT_DEV == 0) && root_wait) {
574 printk(KERN_INFO "Waiting for root device %s...\n",
575 saved_root_name);
576 while (driver_probe_done() != 0 ||
577 (ROOT_DEV = name_to_dev_t(saved_root_name)) == 0)
578 msleep(100);
579 async_synchronize_full();
580 }
581
582 is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR;
583
584 if (is_floppy && rd_doload && rd_load_disk(0))
585 ROOT_DEV = Root_RAM0;
586
587 mount_root();
588out:
589 devtmpfs_mount("dev");
590 sys_mount(".", "/", NULL, MS_MOVE, NULL);
591 sys_chroot(".");
592}
593
594static bool is_tmpfs;
595static struct dentry *rootfs_mount(struct file_system_type *fs_type,
596 int flags, const char *dev_name, void *data)
597{
598 static unsigned long once;
599 void *fill = ramfs_fill_super;
600
601 if (test_and_set_bit(0, &once))
602 return ERR_PTR(-ENODEV);
603
604 if (IS_ENABLED(CONFIG_TMPFS) && is_tmpfs)
605 fill = shmem_fill_super;
606
607 return mount_nodev(fs_type, flags, data, fill);
608}
609
610static struct file_system_type rootfs_fs_type = {
611 .name = "rootfs",
612 .mount = rootfs_mount,
613 .kill_sb = kill_litter_super,
614};
615
616int __init init_rootfs(void)
617{
618 int err = register_filesystem(&rootfs_fs_type);
619
620 if (err)
621 return err;
622
623 if (IS_ENABLED(CONFIG_TMPFS) && !saved_root_name[0] &&
624 (!root_fs_names || strstr(root_fs_names, "tmpfs"))) {
625 err = shmem_init();
626 is_tmpfs = true;
627 } else {
628 err = init_ramfs_fs();
629 }
630
631 if (err)
632 unregister_filesystem(&rootfs_fs_type);
633
634 return err;
635}
636