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  1// SPDX-License-Identifier: GPL-2.0-only
  2#include <linux/module.h>
  3#include <linux/sched.h>
  4#include <linux/ctype.h>
  5#include <linux/fd.h>
  6#include <linux/tty.h>
  7#include <linux/suspend.h>
  8#include <linux/root_dev.h>
  9#include <linux/security.h>
 10#include <linux/delay.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#include <linux/ramfs.h>
 20#include <linux/shmem_fs.h>
 21#include <linux/ktime.h>
 22
 23#include <linux/nfs_fs.h>
 24#include <linux/nfs_fs_sb.h>
 25#include <linux/nfs_mount.h>
 26#include <linux/raid/detect.h>
 27#include <uapi/linux/mount.h>
 28
 29#include "do_mounts.h"
 30
 31int root_mountflags = MS_RDONLY | MS_SILENT;
 32static char __initdata saved_root_name[64];
 33static int root_wait;
 34
 35dev_t ROOT_DEV;
 36
 37static int __init load_ramdisk(char *str)
 38{
 39	pr_warn("ignoring the deprecated load_ramdisk= option\n");
 40	return 1;
 41}
 42__setup("load_ramdisk=", load_ramdisk);
 43
 44static int __init readonly(char *str)
 45{
 46	if (*str)
 47		return 0;
 48	root_mountflags |= MS_RDONLY;
 49	return 1;
 50}
 51
 52static int __init readwrite(char *str)
 53{
 54	if (*str)
 55		return 0;
 56	root_mountflags &= ~MS_RDONLY;
 57	return 1;
 58}
 59
 60__setup("ro", readonly);
 61__setup("rw", readwrite);
 62
 63static int __init root_dev_setup(char *line)
 64{
 65	strscpy(saved_root_name, line, sizeof(saved_root_name));
 66	return 1;
 67}
 68
 69__setup("root=", root_dev_setup);
 70
 71static int __init rootwait_setup(char *str)
 72{
 73	if (*str)
 74		return 0;
 75	root_wait = -1;
 76	return 1;
 77}
 78
 79__setup("rootwait", rootwait_setup);
 80
 81static int __init rootwait_timeout_setup(char *str)
 82{
 83	int sec;
 84
 85	if (kstrtoint(str, 0, &sec) || sec < 0) {
 86		pr_warn("ignoring invalid rootwait value\n");
 87		goto ignore;
 88	}
 89
 90	if (check_mul_overflow(sec, MSEC_PER_SEC, &root_wait)) {
 91		pr_warn("ignoring excessive rootwait value\n");
 92		goto ignore;
 93	}
 94
 95	return 1;
 96
 97ignore:
 98	/* Fallback to indefinite wait */
 99	root_wait = -1;
100
101	return 1;
102}
103
104__setup("rootwait=", rootwait_timeout_setup);
105
106static char * __initdata root_mount_data;
107static int __init root_data_setup(char *str)
108{
109	root_mount_data = str;
110	return 1;
111}
112
113static char * __initdata root_fs_names;
114static int __init fs_names_setup(char *str)
115{
116	root_fs_names = str;
117	return 1;
118}
119
120static unsigned int __initdata root_delay;
121static int __init root_delay_setup(char *str)
122{
123	root_delay = simple_strtoul(str, NULL, 0);
124	return 1;
125}
126
127__setup("rootflags=", root_data_setup);
128__setup("rootfstype=", fs_names_setup);
129__setup("rootdelay=", root_delay_setup);
130
131/* This can return zero length strings. Caller should check */
132static int __init split_fs_names(char *page, size_t size)
133{
134	int count = 1;
135	char *p = page;
136
137	strscpy(p, root_fs_names, size);
138	while (*p++) {
139		if (p[-1] == ',') {
140			p[-1] = '\0';
141			count++;
142		}
143	}
144
145	return count;
146}
147
148static int __init do_mount_root(const char *name, const char *fs,
149				 const int flags, const void *data)
150{
151	struct super_block *s;
152	struct page *p = NULL;
153	char *data_page = NULL;
154	int ret;
155
156	if (data) {
157		/* init_mount() requires a full page as fifth argument */
158		p = alloc_page(GFP_KERNEL);
159		if (!p)
160			return -ENOMEM;
161		data_page = page_address(p);
162		/* zero-pad. init_mount() will make sure it's terminated */
163		strncpy(data_page, data, PAGE_SIZE);
164	}
165
166	ret = init_mount(name, "/root", fs, flags, data_page);
167	if (ret)
168		goto out;
169
170	init_chdir("/root");
171	s = current->fs->pwd.dentry->d_sb;
172	ROOT_DEV = s->s_dev;
173	printk(KERN_INFO
174	       "VFS: Mounted root (%s filesystem)%s on device %u:%u.\n",
175	       s->s_type->name,
176	       sb_rdonly(s) ? " readonly" : "",
177	       MAJOR(ROOT_DEV), MINOR(ROOT_DEV));
178
179out:
180	if (p)
181		put_page(p);
182	return ret;
183}
184
185void __init mount_root_generic(char *name, char *pretty_name, int flags)
186{
187	struct page *page = alloc_page(GFP_KERNEL);
188	char *fs_names = page_address(page);
189	char *p;
190	char b[BDEVNAME_SIZE];
191	int num_fs, i;
192
193	scnprintf(b, BDEVNAME_SIZE, "unknown-block(%u,%u)",
194		  MAJOR(ROOT_DEV), MINOR(ROOT_DEV));
195	if (root_fs_names)
196		num_fs = split_fs_names(fs_names, PAGE_SIZE);
197	else
198		num_fs = list_bdev_fs_names(fs_names, PAGE_SIZE);
199retry:
200	for (i = 0, p = fs_names; i < num_fs; i++, p += strlen(p)+1) {
201		int err;
202
203		if (!*p)
204			continue;
205		err = do_mount_root(name, p, flags, root_mount_data);
206		switch (err) {
207			case 0:
208				goto out;
209			case -EACCES:
210			case -EINVAL:
211				continue;
212		}
213	        /*
214		 * Allow the user to distinguish between failed sys_open
215		 * and bad superblock on root device.
216		 * and give them a list of the available devices
217		 */
218		printk("VFS: Cannot open root device \"%s\" or %s: error %d\n",
219				pretty_name, b, err);
220		printk("Please append a correct \"root=\" boot option; here are the available partitions:\n");
221		printk_all_partitions();
222
223		if (root_fs_names)
224			num_fs = list_bdev_fs_names(fs_names, PAGE_SIZE);
225		if (!num_fs)
226			pr_err("Can't find any bdev filesystem to be used for mount!\n");
227		else {
228			pr_err("List of all bdev filesystems:\n");
229			for (i = 0, p = fs_names; i < num_fs; i++, p += strlen(p)+1)
230				pr_err(" %s", p);
231			pr_err("\n");
232		}
233
234		panic("VFS: Unable to mount root fs on %s", b);
235	}
236	if (!(flags & SB_RDONLY)) {
237		flags |= SB_RDONLY;
238		goto retry;
239	}
240
241	printk("List of all partitions:\n");
242	printk_all_partitions();
243	printk("No filesystem could mount root, tried: ");
244	for (i = 0, p = fs_names; i < num_fs; i++, p += strlen(p)+1)
245		printk(" %s", p);
246	printk("\n");
247	panic("VFS: Unable to mount root fs on \"%s\" or %s", pretty_name, b);
248out:
249	put_page(page);
250}
251 
252#ifdef CONFIG_ROOT_NFS
253
254#define NFSROOT_TIMEOUT_MIN	5
255#define NFSROOT_TIMEOUT_MAX	30
256#define NFSROOT_RETRY_MAX	5
257
258static void __init mount_nfs_root(void)
259{
260	char *root_dev, *root_data;
261	unsigned int timeout;
262	int try;
263
264	if (nfs_root_data(&root_dev, &root_data))
265		goto fail;
266
267	/*
268	 * The server or network may not be ready, so try several
269	 * times.  Stop after a few tries in case the client wants
270	 * to fall back to other boot methods.
271	 */
272	timeout = NFSROOT_TIMEOUT_MIN;
273	for (try = 1; ; try++) {
274		if (!do_mount_root(root_dev, "nfs", root_mountflags, root_data))
275			return;
276		if (try > NFSROOT_RETRY_MAX)
277			break;
278
279		/* Wait, in case the server refused us immediately */
280		ssleep(timeout);
281		timeout <<= 1;
282		if (timeout > NFSROOT_TIMEOUT_MAX)
283			timeout = NFSROOT_TIMEOUT_MAX;
284	}
285fail:
286	pr_err("VFS: Unable to mount root fs via NFS.\n");
287}
288#else
289static inline void mount_nfs_root(void)
290{
291}
292#endif /* CONFIG_ROOT_NFS */
293
294#ifdef CONFIG_CIFS_ROOT
295
296#define CIFSROOT_TIMEOUT_MIN	5
297#define CIFSROOT_TIMEOUT_MAX	30
298#define CIFSROOT_RETRY_MAX	5
299
300static void __init mount_cifs_root(void)
301{
302	char *root_dev, *root_data;
303	unsigned int timeout;
304	int try;
305
306	if (cifs_root_data(&root_dev, &root_data))
307		goto fail;
308
309	timeout = CIFSROOT_TIMEOUT_MIN;
310	for (try = 1; ; try++) {
311		if (!do_mount_root(root_dev, "cifs", root_mountflags,
312				   root_data))
313			return;
314		if (try > CIFSROOT_RETRY_MAX)
315			break;
316
317		ssleep(timeout);
318		timeout <<= 1;
319		if (timeout > CIFSROOT_TIMEOUT_MAX)
320			timeout = CIFSROOT_TIMEOUT_MAX;
321	}
322fail:
323	pr_err("VFS: Unable to mount root fs via SMB.\n");
324}
325#else
326static inline void mount_cifs_root(void)
327{
328}
329#endif /* CONFIG_CIFS_ROOT */
330
331static bool __init fs_is_nodev(char *fstype)
332{
333	struct file_system_type *fs = get_fs_type(fstype);
334	bool ret = false;
335
336	if (fs) {
337		ret = !(fs->fs_flags & FS_REQUIRES_DEV);
338		put_filesystem(fs);
339	}
340
341	return ret;
342}
343
344static int __init mount_nodev_root(char *root_device_name)
345{
346	char *fs_names, *fstype;
347	int err = -EINVAL;
348	int num_fs, i;
349
350	fs_names = (void *)__get_free_page(GFP_KERNEL);
351	if (!fs_names)
352		return -EINVAL;
353	num_fs = split_fs_names(fs_names, PAGE_SIZE);
354
355	for (i = 0, fstype = fs_names; i < num_fs;
356	     i++, fstype += strlen(fstype) + 1) {
357		if (!*fstype)
358			continue;
359		if (!fs_is_nodev(fstype))
360			continue;
361		err = do_mount_root(root_device_name, fstype, root_mountflags,
362				    root_mount_data);
363		if (!err)
364			break;
365	}
366
367	free_page((unsigned long)fs_names);
368	return err;
369}
370
371#ifdef CONFIG_BLOCK
372static void __init mount_block_root(char *root_device_name)
373{
374	int err = create_dev("/dev/root", ROOT_DEV);
375
376	if (err < 0)
377		pr_emerg("Failed to create /dev/root: %d\n", err);
378	mount_root_generic("/dev/root", root_device_name, root_mountflags);
379}
380#else
381static inline void mount_block_root(char *root_device_name)
382{
383}
384#endif /* CONFIG_BLOCK */
385
386void __init mount_root(char *root_device_name)
387{
388	switch (ROOT_DEV) {
389	case Root_NFS:
390		mount_nfs_root();
391		break;
392	case Root_CIFS:
393		mount_cifs_root();
394		break;
395	case Root_Generic:
396		mount_root_generic(root_device_name, root_device_name,
397				   root_mountflags);
398		break;
399	case 0:
400		if (root_device_name && root_fs_names &&
401		    mount_nodev_root(root_device_name) == 0)
402			break;
403		fallthrough;
404	default:
405		mount_block_root(root_device_name);
406		break;
407	}
408}
409
410/* wait for any asynchronous scanning to complete */
411static void __init wait_for_root(char *root_device_name)
412{
413	ktime_t end;
414
415	if (ROOT_DEV != 0)
416		return;
417
418	pr_info("Waiting for root device %s...\n", root_device_name);
419
420	end = ktime_add_ms(ktime_get_raw(), root_wait);
421
422	while (!driver_probe_done() ||
423	       early_lookup_bdev(root_device_name, &ROOT_DEV) < 0) {
424		msleep(5);
425		if (root_wait > 0 && ktime_after(ktime_get_raw(), end))
426			break;
427	}
428
429	async_synchronize_full();
430
431}
432
433static dev_t __init parse_root_device(char *root_device_name)
434{
435	int error;
436	dev_t dev;
437
438	if (!strncmp(root_device_name, "mtd", 3) ||
439	    !strncmp(root_device_name, "ubi", 3))
440		return Root_Generic;
441	if (strcmp(root_device_name, "/dev/nfs") == 0)
442		return Root_NFS;
443	if (strcmp(root_device_name, "/dev/cifs") == 0)
444		return Root_CIFS;
445	if (strcmp(root_device_name, "/dev/ram") == 0)
446		return Root_RAM0;
447
448	error = early_lookup_bdev(root_device_name, &dev);
449	if (error) {
450		if (error == -EINVAL && root_wait) {
451			pr_err("Disabling rootwait; root= is invalid.\n");
452			root_wait = 0;
453		}
454		return 0;
455	}
456	return dev;
457}
458
459/*
460 * Prepare the namespace - decide what/where to mount, load ramdisks, etc.
461 */
462void __init prepare_namespace(void)
463{
464	if (root_delay) {
465		printk(KERN_INFO "Waiting %d sec before mounting root device...\n",
466		       root_delay);
467		ssleep(root_delay);
468	}
469
470	/*
471	 * wait for the known devices to complete their probing
472	 *
473	 * Note: this is a potential source of long boot delays.
474	 * For example, it is not atypical to wait 5 seconds here
475	 * for the touchpad of a laptop to initialize.
476	 */
477	wait_for_device_probe();
478
479	md_run_setup();
480
481	if (saved_root_name[0])
482		ROOT_DEV = parse_root_device(saved_root_name);
483
484	if (initrd_load(saved_root_name))
485		goto out;
486
487	if (root_wait)
488		wait_for_root(saved_root_name);
489	mount_root(saved_root_name);
490out:
491	devtmpfs_mount();
492	init_mount(".", "/", NULL, MS_MOVE, NULL);
493	init_chroot(".");
494}
495
496static bool is_tmpfs;
497static int rootfs_init_fs_context(struct fs_context *fc)
498{
499	if (IS_ENABLED(CONFIG_TMPFS) && is_tmpfs)
500		return shmem_init_fs_context(fc);
501
502	return ramfs_init_fs_context(fc);
503}
504
505struct file_system_type rootfs_fs_type = {
506	.name		= "rootfs",
507	.init_fs_context = rootfs_init_fs_context,
508	.kill_sb	= kill_litter_super,
509};
510
511void __init init_rootfs(void)
512{
513	if (IS_ENABLED(CONFIG_TMPFS)) {
514		if (!saved_root_name[0] && !root_fs_names)
515			is_tmpfs = true;
516		else if (root_fs_names && !!strstr(root_fs_names, "tmpfs"))
517			is_tmpfs = true;
518	}
519}
  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}