blob: adb7cad3e6eec17165efdf88acf1f0f936fc4c9d [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001#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>
Andrew Mortond53d9f12005-07-12 13:58:07 -070010#include <linux/mount.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011
12#include <linux/nfs_fs.h>
13#include <linux/nfs_fs_sb.h>
14#include <linux/nfs_mount.h>
15
16#include "do_mounts.h"
17
18extern int get_filesystem_list(char * buf);
19
20int __initdata rd_doload; /* 1 = load RAM disk, 0 = don't load */
21
Theodore Ts'o9b04c992006-03-24 03:15:10 -080022int root_mountflags = MS_RDONLY | MS_SILENT;
Linus Torvalds1da177e2005-04-16 15:20:36 -070023char * __initdata root_device_name;
24static char __initdata saved_root_name[64];
25
Linus Torvalds1da177e2005-04-16 15:20:36 -070026dev_t ROOT_DEV;
27
Linus Torvalds1da177e2005-04-16 15:20:36 -070028static int __init load_ramdisk(char *str)
29{
30 rd_doload = simple_strtol(str,NULL,0) & 3;
31 return 1;
32}
33__setup("load_ramdisk=", load_ramdisk);
34
35static int __init readonly(char *str)
36{
37 if (*str)
38 return 0;
39 root_mountflags |= MS_RDONLY;
40 return 1;
41}
42
43static int __init readwrite(char *str)
44{
45 if (*str)
46 return 0;
47 root_mountflags &= ~MS_RDONLY;
48 return 1;
49}
50
51__setup("ro", readonly);
52__setup("rw", readwrite);
53
54static dev_t try_name(char *name, int part)
55{
56 char path[64];
57 char buf[32];
58 int range;
59 dev_t res;
60 char *s;
61 int len;
62 int fd;
63 unsigned int maj, min;
64
65 /* read device number from .../dev */
66
67 sprintf(path, "/sys/block/%s/dev", name);
68 fd = sys_open(path, 0, 0);
69 if (fd < 0)
70 goto fail;
71 len = sys_read(fd, buf, 32);
72 sys_close(fd);
73 if (len <= 0 || len == 32 || buf[len - 1] != '\n')
74 goto fail;
75 buf[len - 1] = '\0';
76 if (sscanf(buf, "%u:%u", &maj, &min) == 2) {
77 /*
78 * Try the %u:%u format -- see print_dev_t()
79 */
80 res = MKDEV(maj, min);
81 if (maj != MAJOR(res) || min != MINOR(res))
82 goto fail;
83 } else {
84 /*
85 * Nope. Try old-style "0321"
86 */
87 res = new_decode_dev(simple_strtoul(buf, &s, 16));
88 if (*s)
89 goto fail;
90 }
91
92 /* if it's there and we are not looking for a partition - that's it */
93 if (!part)
94 return res;
95
96 /* otherwise read range from .../range */
97 sprintf(path, "/sys/block/%s/range", name);
98 fd = sys_open(path, 0, 0);
99 if (fd < 0)
100 goto fail;
101 len = sys_read(fd, buf, 32);
102 sys_close(fd);
103 if (len <= 0 || len == 32 || buf[len - 1] != '\n')
104 goto fail;
105 buf[len - 1] = '\0';
106 range = simple_strtoul(buf, &s, 10);
107 if (*s)
108 goto fail;
109
110 /* if partition is within range - we got it */
111 if (part < range)
112 return res + part;
113fail:
114 return 0;
115}
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 *
128 * If name doesn't have fall into the categories above, we return 0.
Rolf Eike Beer13ae6d82005-09-02 09:03:09 +0200129 * Sysfs is used to check if something is a disk name - it has
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130 * all known disks under bus/block/devices. If the disk name
Rolf Eike Beer13ae6d82005-09-02 09:03:09 +0200131 * contains slashes, name of sysfs node has them replaced with
132 * bangs. try_name() does the actual checks, assuming that sysfs
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133 * is mounted on rootfs /sys.
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_SYSFS
144 int mkdir_err = sys_mkdir("/sys", 0700);
145 if (sys_mount("sysfs", "/sys", "sysfs", 0, NULL) < 0)
146 goto out;
147#endif
148
149 if (strncmp(name, "/dev/", 5) != 0) {
150 unsigned maj, min;
151
152 if (sscanf(name, "%u:%u", &maj, &min) == 2) {
153 res = MKDEV(maj, min);
154 if (maj != MAJOR(res) || min != MINOR(res))
155 goto fail;
156 } else {
157 res = new_decode_dev(simple_strtoul(name, &p, 16));
158 if (*p)
159 goto fail;
160 }
161 goto done;
162 }
163 name += 5;
164 res = Root_NFS;
165 if (strcmp(name, "nfs") == 0)
166 goto done;
167 res = Root_RAM0;
168 if (strcmp(name, "ram") == 0)
169 goto done;
170
171 if (strlen(name) > 31)
172 goto fail;
173 strcpy(s, name);
174 for (p = s; *p; p++)
175 if (*p == '/')
176 *p = '!';
177 res = try_name(s, 0);
178 if (res)
179 goto done;
180
181 while (p > s && isdigit(p[-1]))
182 p--;
183 if (p == s || !*p || *p == '0')
184 goto fail;
185 part = simple_strtoul(p, NULL, 10);
186 *p = '\0';
187 res = try_name(s, part);
188 if (res)
189 goto done;
190
191 if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
192 goto fail;
193 p[-1] = '\0';
194 res = try_name(s, part);
195done:
196#ifdef CONFIG_SYSFS
197 sys_umount("/sys", 0);
198out:
199 if (!mkdir_err)
200 sys_rmdir("/sys");
201#endif
202 return res;
203fail:
204 res = 0;
205 goto done;
206}
207
208static int __init root_dev_setup(char *line)
209{
210 strlcpy(saved_root_name, line, sizeof(saved_root_name));
211 return 1;
212}
213
214__setup("root=", root_dev_setup);
215
216static char * __initdata root_mount_data;
217static int __init root_data_setup(char *str)
218{
219 root_mount_data = str;
220 return 1;
221}
222
223static char * __initdata root_fs_names;
224static int __init fs_names_setup(char *str)
225{
226 root_fs_names = str;
227 return 1;
228}
229
230static unsigned int __initdata root_delay;
231static int __init root_delay_setup(char *str)
232{
233 root_delay = simple_strtoul(str, NULL, 0);
234 return 1;
235}
236
237__setup("rootflags=", root_data_setup);
238__setup("rootfstype=", fs_names_setup);
239__setup("rootdelay=", root_delay_setup);
240
241static void __init get_fs_names(char *page)
242{
243 char *s = page;
244
245 if (root_fs_names) {
246 strcpy(page, root_fs_names);
247 while (*s++) {
248 if (s[-1] == ',')
249 s[-1] = '\0';
250 }
251 } else {
252 int len = get_filesystem_list(page);
253 char *p, *next;
254
255 page[len] = '\0';
256 for (p = page-1; p; p = next) {
257 next = strchr(++p, '\n');
258 if (*p++ != '\t')
259 continue;
260 while ((*s++ = *p++) != '\n')
261 ;
262 s[-1] = '\0';
263 }
264 }
265 *s = '\0';
266}
267
268static int __init do_mount_root(char *name, char *fs, int flags, void *data)
269{
270 int err = sys_mount(name, "/root", fs, flags, data);
271 if (err)
272 return err;
273
274 sys_chdir("/root");
275 ROOT_DEV = current->fs->pwdmnt->mnt_sb->s_dev;
276 printk("VFS: Mounted root (%s filesystem)%s.\n",
277 current->fs->pwdmnt->mnt_sb->s_type->name,
278 current->fs->pwdmnt->mnt_sb->s_flags & MS_RDONLY ?
279 " readonly" : "");
280 return 0;
281}
282
283void __init mount_block_root(char *name, int flags)
284{
285 char *fs_names = __getname();
286 char *p;
287 char b[BDEVNAME_SIZE];
288
289 get_fs_names(fs_names);
290retry:
291 for (p = fs_names; *p; p += strlen(p)+1) {
292 int err = do_mount_root(name, p, flags, root_mount_data);
293 switch (err) {
294 case 0:
295 goto out;
296 case -EACCES:
297 flags |= MS_RDONLY;
298 goto retry;
299 case -EINVAL:
300 continue;
301 }
302 /*
303 * Allow the user to distinguish between failed sys_open
304 * and bad superblock on root device.
305 */
306 __bdevname(ROOT_DEV, b);
307 printk("VFS: Cannot open root device \"%s\" or %s\n",
308 root_device_name, b);
309 printk("Please append a correct \"root=\" boot option\n");
310
311 panic("VFS: Unable to mount root fs on %s", b);
312 }
313 panic("VFS: Unable to mount root fs on %s", __bdevname(ROOT_DEV, b));
314out:
315 putname(fs_names);
316}
317
318#ifdef CONFIG_ROOT_NFS
319static int __init mount_nfs_root(void)
320{
321 void *data = nfs_root_data();
322
323 create_dev("/dev/root", ROOT_DEV, NULL);
324 if (data &&
325 do_mount_root("/dev/root", "nfs", root_mountflags, data) == 0)
326 return 1;
327 return 0;
328}
329#endif
330
331#if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD)
332void __init change_floppy(char *fmt, ...)
333{
334 struct termios termios;
335 char buf[80];
336 char c;
337 int fd;
338 va_list args;
339 va_start(args, fmt);
340 vsprintf(buf, fmt, args);
341 va_end(args);
342 fd = sys_open("/dev/root", O_RDWR | O_NDELAY, 0);
343 if (fd >= 0) {
344 sys_ioctl(fd, FDEJECT, 0);
345 sys_close(fd);
346 }
347 printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf);
348 fd = sys_open("/dev/console", O_RDWR, 0);
349 if (fd >= 0) {
350 sys_ioctl(fd, TCGETS, (long)&termios);
351 termios.c_lflag &= ~ICANON;
352 sys_ioctl(fd, TCSETSF, (long)&termios);
353 sys_read(fd, &c, 1);
354 termios.c_lflag |= ICANON;
355 sys_ioctl(fd, TCSETSF, (long)&termios);
356 sys_close(fd);
357 }
358}
359#endif
360
361void __init mount_root(void)
362{
363#ifdef CONFIG_ROOT_NFS
364 if (MAJOR(ROOT_DEV) == UNNAMED_MAJOR) {
365 if (mount_nfs_root())
366 return;
367
368 printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n");
369 ROOT_DEV = Root_FD0;
370 }
371#endif
372#ifdef CONFIG_BLK_DEV_FD
373 if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) {
374 /* rd_doload is 2 for a dual initrd/ramload setup */
375 if (rd_doload==2) {
376 if (rd_load_disk(1)) {
377 ROOT_DEV = Root_RAM1;
378 root_device_name = NULL;
379 }
380 } else
381 change_floppy("root floppy");
382 }
383#endif
384 create_dev("/dev/root", ROOT_DEV, root_device_name);
385 mount_block_root("/dev/root", root_mountflags);
386}
387
388/*
389 * Prepare the namespace - decide what/where to mount, load ramdisks, etc.
390 */
391void __init prepare_namespace(void)
392{
393 int is_floppy;
394
395 mount_devfs();
396
397 if (root_delay) {
398 printk(KERN_INFO "Waiting %dsec before mounting root device...\n",
399 root_delay);
400 ssleep(root_delay);
401 }
402
403 md_run_setup();
404
405 if (saved_root_name[0]) {
406 root_device_name = saved_root_name;
407 ROOT_DEV = name_to_dev_t(root_device_name);
408 if (strncmp(root_device_name, "/dev/", 5) == 0)
409 root_device_name += 5;
410 }
411
412 is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR;
413
414 if (initrd_load())
415 goto out;
416
417 if (is_floppy && rd_doload && rd_load_disk(0))
418 ROOT_DEV = Root_RAM0;
419
420 mount_root();
421out:
422 umount_devfs("/dev");
423 sys_mount(".", "/", NULL, MS_MOVE, NULL);
424 sys_chroot(".");
425 security_sb_post_mountroot();
426 mount_devfs_fs ();
427}
428