1 #include <linux/module.h>
2 #include <linux/sched.h>
3 #include <linux/ctype.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>
15 #include <linux/initrd.h>
16 #include <linux/async.h>
17 #include <linux/fs_struct.h>
18 #include <linux/slab.h>
20 #include <linux/nfs_fs.h>
21 #include <linux/nfs_fs_sb.h>
22 #include <linux/nfs_mount.h>
24 #include "do_mounts.h"
26 int __initdata rd_doload; /* 1 = load RAM disk, 0 = don't load */
28 int root_mountflags = MS_RDONLY | MS_SILENT;
29 static char * __initdata root_device_name;
30 static char __initdata saved_root_name[64];
31 static int __initdata root_wait;
35 static int __init load_ramdisk(char *str)
37 rd_doload = simple_strtol(str,NULL,0) & 3;
40 __setup("load_ramdisk=", load_ramdisk);
42 static int __init readonly(char *str)
46 root_mountflags |= MS_RDONLY;
50 static int __init readwrite(char *str)
54 root_mountflags &= ~MS_RDONLY;
58 __setup("ro", readonly);
59 __setup("rw", readwrite);
62 * match_dev_by_uuid - callback for finding a partition using its uuid
63 * @dev: device passed in by the caller
64 * @data: opaque pointer to a 36 byte char array with a UUID
66 * Returns 1 if the device matches, and 0 otherwise.
68 static int __init match_dev_by_uuid(struct device *dev, void *data)
71 struct hd_struct *part = dev_to_part(dev);
76 if (memcmp(uuid, part->info->uuid, sizeof(part->info->uuid)))
86 * devt_from_partuuid - looks up the dev_t of a partition by its UUID
87 * @uuid: 36 byte char array containing a hex ascii UUID
89 * The function will return the first partition which contains a matching
90 * UUID value in its partition_meta_info struct. This does not search
91 * by filesystem UUIDs.
93 * Returns the matching dev_t on success or 0 on failure.
95 static dev_t __init devt_from_partuuid(char *uuid_str)
98 struct device *dev = NULL;
101 /* Pack the requested UUID in the expected format. */
102 part_pack_uuid(uuid_str, uuid);
104 dev = class_find_device(&block_class, NULL, uuid, &match_dev_by_uuid);
116 * Convert a name into device number. We accept the following variants:
118 * 1) device number in hexadecimal represents itself
119 * 2) /dev/nfs represents Root_NFS (0xff)
120 * 3) /dev/<disk_name> represents the device number of disk
121 * 4) /dev/<disk_name><decimal> represents the device number
122 * of partition - device number of disk plus the partition number
123 * 5) /dev/<disk_name>p<decimal> - same as the above, that form is
124 * used when disk name of partitioned disk ends on a digit.
125 * 6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the
126 * unique id of a partition if the partition table provides it.
128 * If name doesn't have fall into the categories above, we return (0,0).
129 * block_class is used to check if something is a disk name. If the disk
130 * name contains slashes, the device name has them replaced with
134 dev_t name_to_dev_t(char *name)
141 if (strncmp(name, "PARTUUID=", 9) == 0) {
143 if (strlen(name) != 36)
145 res = devt_from_partuuid(name);
151 if (strncmp(name, "/dev/", 5) != 0) {
154 if (sscanf(name, "%u:%u", &maj, &min) == 2) {
155 res = MKDEV(maj, min);
156 if (maj != MAJOR(res) || min != MINOR(res))
159 res = new_decode_dev(simple_strtoul(name, &p, 16));
168 if (strcmp(name, "nfs") == 0)
171 if (strcmp(name, "ram") == 0)
174 if (strlen(name) > 31)
180 res = blk_lookup_devt(s, 0);
185 * try non-existant, but valid partition, which may only exist
186 * after revalidating the disk, like partitioned md devices
188 while (p > s && isdigit(p[-1]))
190 if (p == s || !*p || *p == '0')
193 /* try disk name without <part number> */
194 part = simple_strtoul(p, NULL, 10);
196 res = blk_lookup_devt(s, part);
200 /* try disk name without p<part number> */
201 if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
204 res = blk_lookup_devt(s, part);
214 static int __init root_dev_setup(char *line)
216 strlcpy(saved_root_name, line, sizeof(saved_root_name));
220 __setup("root=", root_dev_setup);
222 static int __init rootwait_setup(char *str)
230 __setup("rootwait", rootwait_setup);
232 static char * __initdata root_mount_data;
233 static int __init root_data_setup(char *str)
235 root_mount_data = str;
239 static char * __initdata root_fs_names;
240 static int __init fs_names_setup(char *str)
246 static unsigned int __initdata root_delay;
247 static int __init root_delay_setup(char *str)
249 root_delay = simple_strtoul(str, NULL, 0);
253 __setup("rootflags=", root_data_setup);
254 __setup("rootfstype=", fs_names_setup);
255 __setup("rootdelay=", root_delay_setup);
257 static void __init get_fs_names(char *page)
262 strcpy(page, root_fs_names);
268 int len = get_filesystem_list(page);
272 for (p = page-1; p; p = next) {
273 next = strchr(++p, '\n');
276 while ((*s++ = *p++) != '\n')
284 static int __init do_mount_root(char *name, char *fs, int flags, void *data)
286 int err = sys_mount(name, "/root", fs, flags, data);
291 ROOT_DEV = current->fs->pwd.mnt->mnt_sb->s_dev;
292 printk("VFS: Mounted root (%s filesystem)%s on device %u:%u.\n",
293 current->fs->pwd.mnt->mnt_sb->s_type->name,
294 current->fs->pwd.mnt->mnt_sb->s_flags & MS_RDONLY ?
295 " readonly" : "", MAJOR(ROOT_DEV), MINOR(ROOT_DEV));
299 void __init mount_block_root(char *name, int flags)
301 char *fs_names = __getname_gfp(GFP_KERNEL
302 | __GFP_NOTRACK_FALSE_POSITIVE);
305 char b[BDEVNAME_SIZE];
307 const char *b = name;
310 get_fs_names(fs_names);
312 for (p = fs_names; *p; p += strlen(p)+1) {
313 int err = do_mount_root(name, p, flags, root_mount_data);
324 * Allow the user to distinguish between failed sys_open
325 * and bad superblock on root device.
326 * and give them a list of the available devices
329 __bdevname(ROOT_DEV, b);
331 printk("VFS: Cannot open root device \"%s\" or %s\n",
332 root_device_name, b);
333 printk("Please append a correct \"root=\" boot option; here are the available partitions:\n");
335 printk_all_partitions();
336 #ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
337 printk("DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify "
338 "explicit textual name for \"root=\" boot option.\n");
340 panic("VFS: Unable to mount root fs on %s", b);
343 printk("List of all partitions:\n");
344 printk_all_partitions();
345 printk("No filesystem could mount root, tried: ");
346 for (p = fs_names; *p; p += strlen(p)+1)
350 __bdevname(ROOT_DEV, b);
352 panic("VFS: Unable to mount root fs on %s", b);
357 #ifdef CONFIG_ROOT_NFS
358 static int __init mount_nfs_root(void)
360 void *data = nfs_root_data();
362 create_dev("/dev/root", ROOT_DEV);
364 do_mount_root("/dev/root", "nfs", root_mountflags, data) == 0)
370 #if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD)
371 void __init change_floppy(char *fmt, ...)
373 struct termios termios;
379 vsprintf(buf, fmt, args);
381 fd = sys_open("/dev/root", O_RDWR | O_NDELAY, 0);
383 sys_ioctl(fd, FDEJECT, 0);
386 printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf);
387 fd = sys_open("/dev/console", O_RDWR, 0);
389 sys_ioctl(fd, TCGETS, (long)&termios);
390 termios.c_lflag &= ~ICANON;
391 sys_ioctl(fd, TCSETSF, (long)&termios);
393 termios.c_lflag |= ICANON;
394 sys_ioctl(fd, TCSETSF, (long)&termios);
400 void __init mount_root(void)
402 #ifdef CONFIG_ROOT_NFS
403 if (MAJOR(ROOT_DEV) == UNNAMED_MAJOR) {
404 if (mount_nfs_root())
407 printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n");
411 #ifdef CONFIG_BLK_DEV_FD
412 if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) {
413 /* rd_doload is 2 for a dual initrd/ramload setup */
415 if (rd_load_disk(1)) {
416 ROOT_DEV = Root_RAM1;
417 root_device_name = NULL;
420 change_floppy("root floppy");
424 create_dev("/dev/root", ROOT_DEV);
425 mount_block_root("/dev/root", root_mountflags);
430 * Prepare the namespace - decide what/where to mount, load ramdisks, etc.
432 void __init prepare_namespace(void)
437 printk(KERN_INFO "Waiting %dsec before mounting root device...\n",
443 * wait for the known devices to complete their probing
445 * Note: this is a potential source of long boot delays.
446 * For example, it is not atypical to wait 5 seconds here
447 * for the touchpad of a laptop to initialize.
449 wait_for_device_probe();
453 if (saved_root_name[0]) {
454 root_device_name = saved_root_name;
455 if (!strncmp(root_device_name, "mtd", 3) ||
456 !strncmp(root_device_name, "ubi", 3)) {
457 mount_block_root(root_device_name, root_mountflags);
460 ROOT_DEV = name_to_dev_t(root_device_name);
461 if (strncmp(root_device_name, "/dev/", 5) == 0)
462 root_device_name += 5;
468 /* wait for any asynchronous scanning to complete */
469 if ((ROOT_DEV == 0) && root_wait) {
470 printk(KERN_INFO "Waiting for root device %s...\n",
472 while (driver_probe_done() != 0 ||
473 (ROOT_DEV = name_to_dev_t(saved_root_name)) == 0)
475 async_synchronize_full();
478 is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR;
480 if (is_floppy && rd_doload && rd_load_disk(0))
481 ROOT_DEV = Root_RAM0;
485 devtmpfs_mount("dev");
486 sys_mount(".", "/", NULL, MS_MOVE, NULL);