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
15#include <linux/nfs_fs.h>
16#include <linux/nfs_fs_sb.h>
17#include <linux/nfs_mount.h>
18
19#include "do_mounts.h"
20
21extern int get_filesystem_list(char * buf);
22
23int __initdata rd_doload;	/* 1 = load RAM disk, 0 = don't load */
24
25int root_mountflags = MS_RDONLY | MS_SILENT;
26char * __initdata root_device_name;
27static char __initdata saved_root_name[64];
28
29dev_t ROOT_DEV;
30
31static int __init load_ramdisk(char *str)
32{
33	rd_doload = simple_strtol(str,NULL,0) & 3;
34	return 1;
35}
36__setup("load_ramdisk=", load_ramdisk);
37
38static int __init readonly(char *str)
39{
40	if (*str)
41		return 0;
42	root_mountflags |= MS_RDONLY;
43	return 1;
44}
45
46static int __init readwrite(char *str)
47{
48	if (*str)
49		return 0;
50	root_mountflags &= ~MS_RDONLY;
51	return 1;
52}
53
54__setup("ro", readonly);
55__setup("rw", readwrite);
56
57static dev_t try_name(char *name, int part)
58{
59	char path[64];
60	char buf[32];
61	int range;
62	dev_t res;
63	char *s;
64	int len;
65	int fd;
66	unsigned int maj, min;
67
68	/* read device number from .../dev */
69
70	sprintf(path, "/sys/block/%s/dev", name);
71	fd = sys_open(path, 0, 0);
72	if (fd < 0)
73		goto fail;
74	len = sys_read(fd, buf, 32);
75	sys_close(fd);
76	if (len <= 0 || len == 32 || buf[len - 1] != '\n')
77		goto fail;
78	buf[len - 1] = '\0';
79	if (sscanf(buf, "%u:%u", &maj, &min) == 2) {
80		/*
81		 * Try the %u:%u format -- see print_dev_t()
82		 */
83		res = MKDEV(maj, min);
84		if (maj != MAJOR(res) || min != MINOR(res))
85			goto fail;
86	} else {
87		/*
88		 * Nope.  Try old-style "0321"
89		 */
90		res = new_decode_dev(simple_strtoul(buf, &s, 16));
91		if (*s)
92			goto fail;
93	}
94
95	/* if it's there and we are not looking for a partition - that's it */
96	if (!part)
97		return res;
98
99	/* otherwise read range from .../range */
100	sprintf(path, "/sys/block/%s/range", name);
101	fd = sys_open(path, 0, 0);
102	if (fd < 0)
103		goto fail;
104	len = sys_read(fd, buf, 32);
105	sys_close(fd);
106	if (len <= 0 || len == 32 || buf[len - 1] != '\n')
107		goto fail;
108	buf[len - 1] = '\0';
109	range = simple_strtoul(buf, &s, 10);
110	if (*s)
111		goto fail;
112
113	/* if partition is within range - we got it */
114	if (part < range)
115		return res + part;
116fail:
117	return 0;
118}
119
120/*
121 *	Convert a name into device number.  We accept the following variants:
122 *
123 *	1) device number in hexadecimal	represents itself
124 *	2) /dev/nfs represents Root_NFS (0xff)
125 *	3) /dev/<disk_name> represents the device number of disk
126 *	4) /dev/<disk_name><decimal> represents the device number
127 *         of partition - device number of disk plus the partition number
128 *	5) /dev/<disk_name>p<decimal> - same as the above, that form is
129 *	   used when disk name of partitioned disk ends on a digit.
130 *
131 *	If name doesn't have fall into the categories above, we return 0.
132 *	Sysfs is used to check if something is a disk name - it has
133 *	all known disks under bus/block/devices.  If the disk name
134 *	contains slashes, name of sysfs node has them replaced with
135 *	bangs.  try_name() does the actual checks, assuming that sysfs
136 *	is mounted on rootfs /sys.
137 */
138
139dev_t name_to_dev_t(char *name)
140{
141	char s[32];
142	char *p;
143	dev_t res = 0;
144	int part;
145
146#ifdef CONFIG_SYSFS
147	int mkdir_err = sys_mkdir("/sys", 0700);
148	if (sys_mount("sysfs", "/sys", "sysfs", 0, NULL) < 0)
149		goto out;
150#endif
151
152	if (strncmp(name, "/dev/", 5) != 0) {
153		unsigned maj, min;
154
155		if (sscanf(name, "%u:%u", &maj, &min) == 2) {
156			res = MKDEV(maj, min);
157			if (maj != MAJOR(res) || min != MINOR(res))
158				goto fail;
159		} else {
160			res = new_decode_dev(simple_strtoul(name, &p, 16));
161			if (*p)
162				goto fail;
163		}
164		goto done;
165	}
166	name += 5;
167	res = Root_NFS;
168	if (strcmp(name, "nfs") == 0)
169		goto done;
170	res = Root_RAM0;
171	if (strcmp(name, "ram") == 0)
172		goto done;
173
174	if (strlen(name) > 31)
175		goto fail;
176	strcpy(s, name);
177	for (p = s; *p; p++)
178		if (*p == '/')
179			*p = '!';
180	res = try_name(s, 0);
181	if (res)
182		goto done;
183
184	while (p > s && isdigit(p[-1]))
185		p--;
186	if (p == s || !*p || *p == '0')
187		goto fail;
188	part = simple_strtoul(p, NULL, 10);
189	*p = '\0';
190	res = try_name(s, part);
191	if (res)
192		goto done;
193
194	if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
195		goto fail;
196	p[-1] = '\0';
197	res = try_name(s, part);
198done:
199#ifdef CONFIG_SYSFS
200	sys_umount("/sys", 0);
201out:
202	if (!mkdir_err)
203		sys_rmdir("/sys");
204#endif
205	return res;
206fail:
207	res = 0;
208	goto done;
209}
210
211static int __init root_dev_setup(char *line)
212{
213	strlcpy(saved_root_name, line, sizeof(saved_root_name));
214	return 1;
215}
216
217__setup("root=", root_dev_setup);
218
219static char * __initdata root_mount_data;
220static int __init root_data_setup(char *str)
221{
222	root_mount_data = str;
223	return 1;
224}
225
226static char * __initdata root_fs_names;
227static int __init fs_names_setup(char *str)
228{
229	root_fs_names = str;
230	return 1;
231}
232
233static unsigned int __initdata root_delay;
234static int __init root_delay_setup(char *str)
235{
236	root_delay = simple_strtoul(str, NULL, 0);
237	return 1;
238}
239
240__setup("rootflags=", root_data_setup);
241__setup("rootfstype=", fs_names_setup);
242__setup("rootdelay=", root_delay_setup);
243
244static void __init get_fs_names(char *page)
245{
246	char *s = page;
247
248	if (root_fs_names) {
249		strcpy(page, root_fs_names);
250		while (*s++) {
251			if (s[-1] == ',')
252				s[-1] = '\0';
253		}
254	} else {
255		int len = get_filesystem_list(page);
256		char *p, *next;
257
258		page[len] = '\0';
259		for (p = page-1; p; p = next) {
260			next = strchr(++p, '\n');
261			if (*p++ != '\t')
262				continue;
263			while ((*s++ = *p++) != '\n')
264				;
265			s[-1] = '\0';
266		}
267	}
268	*s = '\0';
269}
270
271static int __init do_mount_root(char *name, char *fs, int flags, void *data)
272{
273	int err = sys_mount(name, "/root", fs, flags, data);
274	if (err)
275		return err;
276
277	sys_chdir("/root");
278	ROOT_DEV = current->fs->pwdmnt->mnt_sb->s_dev;
279	printk("VFS: Mounted root (%s filesystem)%s.\n",
280	       current->fs->pwdmnt->mnt_sb->s_type->name,
281	       current->fs->pwdmnt->mnt_sb->s_flags & MS_RDONLY ?
282	       " readonly" : "");
283	return 0;
284}
285
286void __init mount_block_root(char *name, int flags)
287{
288	char *fs_names = __getname();
289	char *p;
290#ifdef CONFIG_BLOCK
291	char b[BDEVNAME_SIZE];
292#else
293	const char *b = name;
294#endif
295
296	get_fs_names(fs_names);
297retry:
298	for (p = fs_names; *p; p += strlen(p)+1) {
299		int err = do_mount_root(name, p, flags, root_mount_data);
300		switch (err) {
301			case 0:
302				goto out;
303			case -EACCES:
304				flags |= MS_RDONLY;
305				goto retry;
306			case -EINVAL:
307				continue;
308		}
309	        /*
310		 * Allow the user to distinguish between failed sys_open
311		 * and bad superblock on root device.
312		 * and give them a list of the available devices
313		 */
314#ifdef CONFIG_BLOCK
315		__bdevname(ROOT_DEV, b);
316#endif
317		printk("VFS: Cannot open root device \"%s\" or %s\n",
318				root_device_name, b);
319		printk("Please append a correct \"root=\" boot option; here are the available partitions:\n");
320
321		printk_all_partitions();
322		panic("VFS: Unable to mount root fs on %s", b);
323	}
324
325	printk("List of all partitions:\n");
326	printk_all_partitions();
327	printk("No filesystem could mount root, tried: ");
328	for (p = fs_names; *p; p += strlen(p)+1)
329		printk(" %s", p);
330	printk("\n");
331#ifdef CONFIG_BLOCK
332	__bdevname(ROOT_DEV, b);
333#endif
334	panic("VFS: Unable to mount root fs on %s", b);
335out:
336	putname(fs_names);
337}
338
339#ifdef CONFIG_ROOT_NFS
340static int __init mount_nfs_root(void)
341{
342	void *data = nfs_root_data();
343
344	create_dev("/dev/root", ROOT_DEV);
345	if (data &&
346	    do_mount_root("/dev/root", "nfs", root_mountflags, data) == 0)
347		return 1;
348	return 0;
349}
350#endif
351
352#if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD)
353void __init change_floppy(char *fmt, ...)
354{
355	struct termios termios;
356	char buf[80];
357	char c;
358	int fd;
359	va_list args;
360	va_start(args, fmt);
361	vsprintf(buf, fmt, args);
362	va_end(args);
363	fd = sys_open("/dev/root", O_RDWR | O_NDELAY, 0);
364	if (fd >= 0) {
365		sys_ioctl(fd, FDEJECT, 0);
366		sys_close(fd);
367	}
368	printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf);
369	fd = sys_open("/dev/console", O_RDWR, 0);
370	if (fd >= 0) {
371		sys_ioctl(fd, TCGETS, (long)&termios);
372		termios.c_lflag &= ~ICANON;
373		sys_ioctl(fd, TCSETSF, (long)&termios);
374		sys_read(fd, &c, 1);
375		termios.c_lflag |= ICANON;
376		sys_ioctl(fd, TCSETSF, (long)&termios);
377		sys_close(fd);
378	}
379}
380#endif
381
382void __init mount_root(void)
383{
384#ifdef CONFIG_ROOT_NFS
385	if (MAJOR(ROOT_DEV) == UNNAMED_MAJOR) {
386		if (mount_nfs_root())
387			return;
388
389		printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n");
390		ROOT_DEV = Root_FD0;
391	}
392#endif
393#ifdef CONFIG_BLK_DEV_FD
394	if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) {
395		/* rd_doload is 2 for a dual initrd/ramload setup */
396		if (rd_doload==2) {
397			if (rd_load_disk(1)) {
398				ROOT_DEV = Root_RAM1;
399				root_device_name = NULL;
400			}
401		} else
402			change_floppy("root floppy");
403	}
404#endif
405#ifdef CONFIG_BLOCK
406	create_dev("/dev/root", ROOT_DEV);
407	mount_block_root("/dev/root", root_mountflags);
408#endif
409}
410
411/*
412 * Prepare the namespace - decide what/where to mount, load ramdisks, etc.
413 */
414void __init prepare_namespace(void)
415{
416	int is_floppy;
417
418	if (root_delay) {
419		printk(KERN_INFO "Waiting %dsec before mounting root device...\n",
420		       root_delay);
421		ssleep(root_delay);
422	}
423
424	/* wait for the known devices to complete their probing */
425	while (driver_probe_done() != 0)
426		msleep(100);
427
428	md_run_setup();
429
430	if (saved_root_name[0]) {
431		root_device_name = saved_root_name;
432		if (!strncmp(root_device_name, "mtd", 3)) {
433			mount_block_root(root_device_name, root_mountflags);
434			goto out;
435		}
436		ROOT_DEV = name_to_dev_t(root_device_name);
437		if (strncmp(root_device_name, "/dev/", 5) == 0)
438			root_device_name += 5;
439	}
440
441	is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR;
442
443	if (initrd_load())
444		goto out;
445
446	if (is_floppy && rd_doload && rd_load_disk(0))
447		ROOT_DEV = Root_RAM0;
448
449	mount_root();
450out:
451	sys_mount(".", "/", NULL, MS_MOVE, NULL);
452	sys_chroot(".");
453	security_sb_post_mountroot();
454}
455