xref: /openbmc/linux/init/do_mounts.c (revision 643d1f7f)
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 
21 extern int get_filesystem_list(char * buf);
22 
23 int __initdata rd_doload;	/* 1 = load RAM disk, 0 = don't load */
24 
25 int root_mountflags = MS_RDONLY | MS_SILENT;
26 char * __initdata root_device_name;
27 static char __initdata saved_root_name[64];
28 static int __initdata root_wait;
29 
30 dev_t ROOT_DEV;
31 
32 static int __init load_ramdisk(char *str)
33 {
34 	rd_doload = simple_strtol(str,NULL,0) & 3;
35 	return 1;
36 }
37 __setup("load_ramdisk=", load_ramdisk);
38 
39 static int __init readonly(char *str)
40 {
41 	if (*str)
42 		return 0;
43 	root_mountflags |= MS_RDONLY;
44 	return 1;
45 }
46 
47 static int __init readwrite(char *str)
48 {
49 	if (*str)
50 		return 0;
51 	root_mountflags &= ~MS_RDONLY;
52 	return 1;
53 }
54 
55 __setup("ro", readonly);
56 __setup("rw", readwrite);
57 
58 /*
59  *	Convert a name into device number.  We accept the following variants:
60  *
61  *	1) device number in hexadecimal	represents itself
62  *	2) /dev/nfs represents Root_NFS (0xff)
63  *	3) /dev/<disk_name> represents the device number of disk
64  *	4) /dev/<disk_name><decimal> represents the device number
65  *         of partition - device number of disk plus the partition number
66  *	5) /dev/<disk_name>p<decimal> - same as the above, that form is
67  *	   used when disk name of partitioned disk ends on a digit.
68  *
69  *	If name doesn't have fall into the categories above, we return (0,0).
70  *	block_class is used to check if something is a disk name. If the disk
71  *	name contains slashes, the device name has them replaced with
72  *	bangs.
73  */
74 
75 dev_t name_to_dev_t(char *name)
76 {
77 	char s[32];
78 	char *p;
79 	dev_t res = 0;
80 
81 	if (strncmp(name, "/dev/", 5) != 0) {
82 		unsigned maj, min;
83 
84 		if (sscanf(name, "%u:%u", &maj, &min) == 2) {
85 			res = MKDEV(maj, min);
86 			if (maj != MAJOR(res) || min != MINOR(res))
87 				goto fail;
88 		} else {
89 			res = new_decode_dev(simple_strtoul(name, &p, 16));
90 			if (*p)
91 				goto fail;
92 		}
93 		goto done;
94 	}
95 
96 	name += 5;
97 	res = Root_NFS;
98 	if (strcmp(name, "nfs") == 0)
99 		goto done;
100 	res = Root_RAM0;
101 	if (strcmp(name, "ram") == 0)
102 		goto done;
103 
104 	if (strlen(name) > 31)
105 		goto fail;
106 	strcpy(s, name);
107 	for (p = s; *p; p++)
108 		if (*p == '/')
109 			*p = '!';
110 	res = blk_lookup_devt(s);
111 	if (res)
112 		goto done;
113 
114 fail:
115 	return 0;
116 done:
117 	return res;
118 }
119 
120 static int __init root_dev_setup(char *line)
121 {
122 	strlcpy(saved_root_name, line, sizeof(saved_root_name));
123 	return 1;
124 }
125 
126 __setup("root=", root_dev_setup);
127 
128 static int __init rootwait_setup(char *str)
129 {
130 	if (*str)
131 		return 0;
132 	root_wait = 1;
133 	return 1;
134 }
135 
136 __setup("rootwait", rootwait_setup);
137 
138 static char * __initdata root_mount_data;
139 static int __init root_data_setup(char *str)
140 {
141 	root_mount_data = str;
142 	return 1;
143 }
144 
145 static char * __initdata root_fs_names;
146 static int __init fs_names_setup(char *str)
147 {
148 	root_fs_names = str;
149 	return 1;
150 }
151 
152 static unsigned int __initdata root_delay;
153 static int __init root_delay_setup(char *str)
154 {
155 	root_delay = simple_strtoul(str, NULL, 0);
156 	return 1;
157 }
158 
159 __setup("rootflags=", root_data_setup);
160 __setup("rootfstype=", fs_names_setup);
161 __setup("rootdelay=", root_delay_setup);
162 
163 static void __init get_fs_names(char *page)
164 {
165 	char *s = page;
166 
167 	if (root_fs_names) {
168 		strcpy(page, root_fs_names);
169 		while (*s++) {
170 			if (s[-1] == ',')
171 				s[-1] = '\0';
172 		}
173 	} else {
174 		int len = get_filesystem_list(page);
175 		char *p, *next;
176 
177 		page[len] = '\0';
178 		for (p = page-1; p; p = next) {
179 			next = strchr(++p, '\n');
180 			if (*p++ != '\t')
181 				continue;
182 			while ((*s++ = *p++) != '\n')
183 				;
184 			s[-1] = '\0';
185 		}
186 	}
187 	*s = '\0';
188 }
189 
190 static int __init do_mount_root(char *name, char *fs, int flags, void *data)
191 {
192 	int err = sys_mount(name, "/root", fs, flags, data);
193 	if (err)
194 		return err;
195 
196 	sys_chdir("/root");
197 	ROOT_DEV = current->fs->pwdmnt->mnt_sb->s_dev;
198 	printk("VFS: Mounted root (%s filesystem)%s.\n",
199 	       current->fs->pwdmnt->mnt_sb->s_type->name,
200 	       current->fs->pwdmnt->mnt_sb->s_flags & MS_RDONLY ?
201 	       " readonly" : "");
202 	return 0;
203 }
204 
205 void __init mount_block_root(char *name, int flags)
206 {
207 	char *fs_names = __getname();
208 	char *p;
209 #ifdef CONFIG_BLOCK
210 	char b[BDEVNAME_SIZE];
211 #else
212 	const char *b = name;
213 #endif
214 
215 	get_fs_names(fs_names);
216 retry:
217 	for (p = fs_names; *p; p += strlen(p)+1) {
218 		int err = do_mount_root(name, p, flags, root_mount_data);
219 		switch (err) {
220 			case 0:
221 				goto out;
222 			case -EACCES:
223 				flags |= MS_RDONLY;
224 				goto retry;
225 			case -EINVAL:
226 				continue;
227 		}
228 	        /*
229 		 * Allow the user to distinguish between failed sys_open
230 		 * and bad superblock on root device.
231 		 * and give them a list of the available devices
232 		 */
233 #ifdef CONFIG_BLOCK
234 		__bdevname(ROOT_DEV, b);
235 #endif
236 		printk("VFS: Cannot open root device \"%s\" or %s\n",
237 				root_device_name, b);
238 		printk("Please append a correct \"root=\" boot option; here are the available partitions:\n");
239 
240 		printk_all_partitions();
241 		panic("VFS: Unable to mount root fs on %s", b);
242 	}
243 
244 	printk("List of all partitions:\n");
245 	printk_all_partitions();
246 	printk("No filesystem could mount root, tried: ");
247 	for (p = fs_names; *p; p += strlen(p)+1)
248 		printk(" %s", p);
249 	printk("\n");
250 #ifdef CONFIG_BLOCK
251 	__bdevname(ROOT_DEV, b);
252 #endif
253 	panic("VFS: Unable to mount root fs on %s", b);
254 out:
255 	putname(fs_names);
256 }
257 
258 #ifdef CONFIG_ROOT_NFS
259 static int __init mount_nfs_root(void)
260 {
261 	void *data = nfs_root_data();
262 
263 	create_dev("/dev/root", ROOT_DEV);
264 	if (data &&
265 	    do_mount_root("/dev/root", "nfs", root_mountflags, data) == 0)
266 		return 1;
267 	return 0;
268 }
269 #endif
270 
271 #if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD)
272 void __init change_floppy(char *fmt, ...)
273 {
274 	struct termios termios;
275 	char buf[80];
276 	char c;
277 	int fd;
278 	va_list args;
279 	va_start(args, fmt);
280 	vsprintf(buf, fmt, args);
281 	va_end(args);
282 	fd = sys_open("/dev/root", O_RDWR | O_NDELAY, 0);
283 	if (fd >= 0) {
284 		sys_ioctl(fd, FDEJECT, 0);
285 		sys_close(fd);
286 	}
287 	printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf);
288 	fd = sys_open("/dev/console", O_RDWR, 0);
289 	if (fd >= 0) {
290 		sys_ioctl(fd, TCGETS, (long)&termios);
291 		termios.c_lflag &= ~ICANON;
292 		sys_ioctl(fd, TCSETSF, (long)&termios);
293 		sys_read(fd, &c, 1);
294 		termios.c_lflag |= ICANON;
295 		sys_ioctl(fd, TCSETSF, (long)&termios);
296 		sys_close(fd);
297 	}
298 }
299 #endif
300 
301 void __init mount_root(void)
302 {
303 #ifdef CONFIG_ROOT_NFS
304 	if (MAJOR(ROOT_DEV) == UNNAMED_MAJOR) {
305 		if (mount_nfs_root())
306 			return;
307 
308 		printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n");
309 		ROOT_DEV = Root_FD0;
310 	}
311 #endif
312 #ifdef CONFIG_BLK_DEV_FD
313 	if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) {
314 		/* rd_doload is 2 for a dual initrd/ramload setup */
315 		if (rd_doload==2) {
316 			if (rd_load_disk(1)) {
317 				ROOT_DEV = Root_RAM1;
318 				root_device_name = NULL;
319 			}
320 		} else
321 			change_floppy("root floppy");
322 	}
323 #endif
324 #ifdef CONFIG_BLOCK
325 	create_dev("/dev/root", ROOT_DEV);
326 	mount_block_root("/dev/root", root_mountflags);
327 #endif
328 }
329 
330 /*
331  * Prepare the namespace - decide what/where to mount, load ramdisks, etc.
332  */
333 void __init prepare_namespace(void)
334 {
335 	int is_floppy;
336 
337 	if (root_delay) {
338 		printk(KERN_INFO "Waiting %dsec before mounting root device...\n",
339 		       root_delay);
340 		ssleep(root_delay);
341 	}
342 
343 	/* wait for the known devices to complete their probing */
344 	while (driver_probe_done() != 0)
345 		msleep(100);
346 
347 	md_run_setup();
348 
349 	if (saved_root_name[0]) {
350 		root_device_name = saved_root_name;
351 		if (!strncmp(root_device_name, "mtd", 3)) {
352 			mount_block_root(root_device_name, root_mountflags);
353 			goto out;
354 		}
355 		ROOT_DEV = name_to_dev_t(root_device_name);
356 		if (strncmp(root_device_name, "/dev/", 5) == 0)
357 			root_device_name += 5;
358 	}
359 
360 	if (initrd_load())
361 		goto out;
362 
363 	/* wait for any asynchronous scanning to complete */
364 	if ((ROOT_DEV == 0) && root_wait) {
365 		printk(KERN_INFO "Waiting for root device %s...\n",
366 			saved_root_name);
367 		while (driver_probe_done() != 0 ||
368 			(ROOT_DEV = name_to_dev_t(saved_root_name)) == 0)
369 			msleep(100);
370 	}
371 
372 	is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR;
373 
374 	if (is_floppy && rd_doload && rd_load_disk(0))
375 		ROOT_DEV = Root_RAM0;
376 
377 	mount_root();
378 out:
379 	sys_mount(".", "/", NULL, MS_MOVE, NULL);
380 	sys_chroot(".");
381 }
382 
383