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