release/src-rt-6.x.4708/linux/linux-2.6.36/init/do_mounts.c

   1 /* Modified by Broadcom Corp. Portions Copyright (c) Broadcom Corp, 2012. */
   2 #include <linux/module.h>
   3 #include <linux/sched.h>
   4 #include <linux/ctype.h>
   5 #include <linux/fd.h>
   6 #include <linux/tty.h>
   7 #include <linux/suspend.h>
   8 #include <linux/root_dev.h>
   9 #include <linux/security.h>
  10 #include <linux/delay.h>
  11 #include <linux/genhd.h>
  12 #include <linux/mount.h>
  13 #include <linux/device.h>
  14 #include <linux/init.h>
  15 #include <linux/fs.h>
  16 #include <linux/initrd.h>
  17 #include <linux/async.h>
  18 #include <linux/fs_struct.h>
  19 #include <linux/slab.h>
  20
  21 #include <linux/nfs_fs.h>
  22 #include <linux/nfs_fs_sb.h>
  23 #include <linux/nfs_mount.h>
  24
  25 #include "do_mounts.h"
  26
  27 int __initdata rd_doload;       /* 1 = load RAM disk, 0 = don't load */
  28
  29 int root_mountflags = MS_RDONLY | MS_SILENT;
  30 static char * __initdata root_device_name;
  31 #ifdef CONFIG_BCM47XX
  32 char __initdata saved_root_name[64];
  33 #else
  34 static char __initdata saved_root_name[64];
  35 #endif
  36 static int __initdata root_wait;
  37
  38 dev_t ROOT_DEV;
  39
  40 static int __init load_ramdisk(char *str)
  41 {
  42         rd_doload = simple_strtol(str,NULL,0) & 3;
  43         return 1;
  44 }
  45 __setup("load_ramdisk=", load_ramdisk);
  46
  47 static int __init readonly(char *str)
  48 {
  49         if (*str)
  50                 return 0;
  51         root_mountflags |= MS_RDONLY;
  52         return 1;
  53 }
  54
  55 static int __init readwrite(char *str)
  56 {
  57         if (*str)
  58                 return 0;
  59         root_mountflags &= ~MS_RDONLY;
  60         return 1;
  61 }
  62
  63 __setup("ro", readonly);
  64 __setup("rw", readwrite);
  65
  66 /*
  67  *      Convert a name into device number.  We accept the following variants:
  68  *
  69  *      1) device number in hexadecimal represents itself
  70  *      2) /dev/nfs represents Root_NFS (0xff)
  71  *      3) /dev/<disk_name> represents the device number of disk
  72  *      4) /dev/<disk_name><decimal> represents the device number
  73  *         of partition - device number of disk plus the partition number
  74  *      5) /dev/<disk_name>p<decimal> - same as the above, that form is
  75  *         used when disk name of partitioned disk ends on a digit.
  76  *
  77  *      If name doesn't have fall into the categories above, we return (0,0).
  78  *      block_class is used to check if something is a disk name. If the disk
  79  *      name contains slashes, the device name has them replaced with
  80  *      bangs.
  81  */
  82
  83 dev_t name_to_dev_t(char *name)
  84 {
  85         char s[32];
  86         char *p;
  87         dev_t res = 0;
  88         int part;
  89
  90         if (strncmp(name, "/dev/", 5) != 0) {
  91                 unsigned maj, min;
  92
  93                 if (sscanf(name, "%u:%u", &maj, &min) == 2) {
  94                         res = MKDEV(maj, min);
  95                         if (maj != MAJOR(res) || min != MINOR(res))
  96                                 goto fail;
  97                 } else {
  98                         res = new_decode_dev(simple_strtoul(name, &p, 16));
  99                         if (*p)
 100                                 goto fail;
 101                 }
 102                 goto done;
 103         }
 104
 105         name += 5;
 106         res = Root_NFS;
 107         if (strcmp(name, "nfs") == 0)
 108                 goto done;
 109         res = Root_RAM0;
 110         if (strcmp(name, "ram") == 0)
 111                 goto done;
 112
 113         if (strlen(name) > 31)
 114                 goto fail;
 115         strcpy(s, name);
 116         for (p = s; *p; p++)
 117                 if (*p == '/')
 118                         *p = '!';
 119         res = blk_lookup_devt(s, 0);
 120         if (res)
 121                 goto done;
 122
 123         /*
 124          * try non-existant, but valid partition, which may only exist
 125          * after revalidating the disk, like partitioned md devices
 126          */
 127         while (p > s && isdigit(p[-1]))
 128                 p--;
 129         if (p == s || !*p || *p == '0')
 130                 goto fail;
 131
 132         /* try disk name without <part number> */
 133         part = simple_strtoul(p, NULL, 10);
 134         *p = '\0';
 135         res = blk_lookup_devt(s, part);
 136         if (res)
 137                 goto done;
 138
 139         /* try disk name without p<part number> */
 140         if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
 141                 goto fail;
 142         p[-1] = '\0';
 143         res = blk_lookup_devt(s, part);
 144         if (res)
 145                 goto done;
 146
 147 fail:
 148         return 0;
 149 done:
 150         return res;
 151 }
 152
 153 static int __init root_dev_setup(char *line)
 154 {
 155         strlcpy(saved_root_name, line, sizeof(saved_root_name));
 156         return 1;
 157 }
 158
 159 __setup("root=", root_dev_setup);
 160
 161 static int __init rootwait_setup(char *str)
 162 {
 163         if (*str)
 164                 return 0;
 165         root_wait = 1;
 166         return 1;
 167 }
 168
 169 __setup("rootwait", rootwait_setup);
 170
 171 static char * __initdata root_mount_data;
 172 static int __init root_data_setup(char *str)
 173 {
 174         root_mount_data = str;
 175         return 1;
 176 }
 177
 178 static char * __initdata root_fs_names;
 179 static int __init fs_names_setup(char *str)
 180 {
 181         root_fs_names = str;
 182         return 1;
 183 }
 184
 185 static unsigned int __initdata root_delay;
 186 static int __init root_delay_setup(char *str)
 187 {
 188         root_delay = simple_strtoul(str, NULL, 0);
 189         return 1;
 190 }
 191
 192 __setup("rootflags=", root_data_setup);
 193 __setup("rootfstype=", fs_names_setup);
 194 __setup("rootdelay=", root_delay_setup);
 195
 196 static void __init get_fs_names(char *page)
 197 {
 198         char *s = page;
 199
 200         if (root_fs_names) {
 201                 strcpy(page, root_fs_names);
 202                 while (*s++) {
 203                         if (s[-1] == ',')
 204                                 s[-1] = '\0';
 205                 }
 206         } else {
 207                 int len = get_filesystem_list(page);
 208                 char *p, *next;
 209
 210                 page[len] = '\0';
 211                 for (p = page-1; p; p = next) {
 212                         next = strchr(++p, '\n');
 213                         if (*p++ != '\t')
 214                                 continue;
 215                         while ((*s++ = *p++) != '\n')
 216                                 ;
 217                         s[-1] = '\0';
 218                 }
 219         }
 220         *s = '\0';
 221 }
 222
 223 static int __init do_mount_root(char *name, char *fs, int flags, void *data)
 224 {
 225         int err = sys_mount(name, "/root", fs, flags, data);
 226         if (err)
 227                 return err;
 228
 229         sys_chdir("/root");
 230         ROOT_DEV = current->fs->pwd.mnt->mnt_sb->s_dev;
 231         printk("VFS: Mounted root (%s filesystem)%s on device %u:%u.\n",
 232                current->fs->pwd.mnt->mnt_sb->s_type->name,
 233                current->fs->pwd.mnt->mnt_sb->s_flags & MS_RDONLY ?
 234                " readonly" : "", MAJOR(ROOT_DEV), MINOR(ROOT_DEV));
 235         return 0;
 236 }
 237
 238 void __init mount_block_root(char *name, int flags)
 239 {
 240         char *fs_names = __getname_gfp(GFP_KERNEL
 241                 | __GFP_NOTRACK_FALSE_POSITIVE);
 242         char *p;
 243 #ifdef CONFIG_BLOCK
 244         char b[BDEVNAME_SIZE];
 245 #else
 246         const char *b = name;
 247 #endif
 248
 249         get_fs_names(fs_names);
 250 retry:
 251         for (p = fs_names; *p; p += strlen(p)+1) {
 252                 int err = do_mount_root(name, p, flags, root_mount_data);
 253                 switch (err) {
 254                         case 0:
 255                                 goto out;
 256                         case -EACCES:
 257                                 flags |= MS_RDONLY;
 258                                 goto retry;
 259                         case -EINVAL:
 260                                 continue;
 261                 }
 262                 /*
 263                  * Allow the user to distinguish between failed sys_open
 264                  * and bad superblock on root device.
 265                  * and give them a list of the available devices
 266                  */
 267 #ifdef CONFIG_BLOCK
 268                 __bdevname(ROOT_DEV, b);
 269 #endif
 270                 printk("VFS: Cannot open root device \"%s\" or %s\n",
 271                                 root_device_name, b);
 272                 printk("Please append a correct \"root=\" boot option; here are the available partitions:\n");
 273
 274                 printk_all_partitions();
 275 #ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
 276                 printk("DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify "
 277                        "explicit textual name for \"root=\" boot option.\n");
 278 #endif
 279                 panic("VFS: Unable to mount root fs on %s", b);
 280         }
 281
 282         printk("List of all partitions:\n");
 283         printk_all_partitions();
 284         printk("No filesystem could mount root, tried: ");
 285         for (p = fs_names; *p; p += strlen(p)+1)
 286                 printk(" %s", p);
 287         printk("\n");
 288 #ifdef CONFIG_BLOCK
 289         __bdevname(ROOT_DEV, b);
 290 #endif
 291         panic("VFS: Unable to mount root fs on %s", b);
 292 out:
 293         putname(fs_names);
 294 }
 295
 296 #ifdef CONFIG_ROOT_NFS
 297 static int __init mount_nfs_root(void)
 298 {
 299         void *data = nfs_root_data();
 300
 301         create_dev("/dev/root", ROOT_DEV);
 302         if (data &&
 303             do_mount_root("/dev/root", "nfs", root_mountflags, data) == 0)
 304                 return 1;
 305         return 0;
 306 }
 307 #endif
 308
 309 #if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD)
 310 void __init change_floppy(char *fmt, ...)
 311 {
 312         struct termios termios;
 313         char buf[80];
 314         char c;
 315         int fd;
 316         va_list args;
 317         va_start(args, fmt);
 318         vsprintf(buf, fmt, args);
 319         va_end(args);
 320         fd = sys_open("/dev/root", O_RDWR | O_NDELAY, 0);
 321         if (fd >= 0) {
 322                 sys_ioctl(fd, FDEJECT, 0);
 323                 sys_close(fd);
 324         }
 325         printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf);
 326         fd = sys_open("/dev/console", O_RDWR, 0);
 327         if (fd >= 0) {
 328                 sys_ioctl(fd, TCGETS, (long)&termios);
 329                 termios.c_lflag &= ~ICANON;
 330                 sys_ioctl(fd, TCSETSF, (long)&termios);
 331                 sys_read(fd, &c, 1);
 332                 termios.c_lflag |= ICANON;
 333                 sys_ioctl(fd, TCSETSF, (long)&termios);
 334                 sys_close(fd);
 335         }
 336 }
 337 #endif
 338
 339 void __init mount_root(void)
 340 {
 341 #ifdef CONFIG_ROOT_NFS
 342         if (MAJOR(ROOT_DEV) == UNNAMED_MAJOR) {
 343                 if (mount_nfs_root())
 344                         return;
 345
 346                 printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n");
 347                 ROOT_DEV = Root_FD0;
 348         }
 349 #endif
 350 #ifdef CONFIG_BLK_DEV_FD
 351         if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) {
 352                 /* rd_doload is 2 for a dual initrd/ramload setup */
 353                 if (rd_doload==2) {
 354                         if (rd_load_disk(1)) {
 355                                 ROOT_DEV = Root_RAM1;
 356                                 root_device_name = NULL;
 357                         }
 358                 } else
 359                         change_floppy("root floppy");
 360         }
 361 #endif
 362 #ifdef CONFIG_BLOCK
 363         create_dev("/dev/root", ROOT_DEV);
 364         mount_block_root("/dev/root", root_mountflags);
 365 #endif
 366 }
 367
 368 /*
 369  * Prepare the namespace - decide what/where to mount, load ramdisks, etc.
 370  */
 371 void __init prepare_namespace(void)
 372 {
 373         int is_floppy;
 374
 375         if (root_delay) {
 376                 printk(KERN_INFO "Waiting %dsec before mounting root device...\n",
 377                        root_delay);
 378                 ssleep(root_delay);
 379         }
 380
 381         /*
 382          * wait for the known devices to complete their probing
 383          *
 384          * Note: this is a potential source of long boot delays.
 385          * For example, it is not atypical to wait 5 seconds here
 386          * for the touchpad of a laptop to initialize.
 387          */
 388         wait_for_device_probe();
 389
 390         md_run_setup();
 391
 392         if (saved_root_name[0]) {
 393                 root_device_name = saved_root_name;
 394                 if (!strncmp(root_device_name, "mtd", 3) ||
 395                     !strncmp(root_device_name, "ubi", 3)) {
 396                         mount_block_root(root_device_name, root_mountflags);
 397                         goto out;
 398                 }
 399                 ROOT_DEV = name_to_dev_t(root_device_name);
 400                 if (strncmp(root_device_name, "/dev/", 5) == 0)
 401                         root_device_name += 5;
 402         }
 403
 404         if (initrd_load())
 405                 goto out;
 406
 407         /* wait for any asynchronous scanning to complete */
 408         if ((ROOT_DEV == 0) && root_wait) {
 409                 printk(KERN_INFO "Waiting for root device %s...\n",
 410                         saved_root_name);
 411                 while (driver_probe_done() != 0 ||
 412                         (ROOT_DEV = name_to_dev_t(saved_root_name)) == 0)
 413                         msleep(100);
 414                 async_synchronize_full();
 415         }
 416
 417         is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR;
 418
 419         if (is_floppy && rd_doload && rd_load_disk(0))
 420                 ROOT_DEV = Root_RAM0;
 421
 422         mount_root();
 423 out:
 424         devtmpfs_mount("dev");
 425         sys_mount(".", "/", NULL, MS_MOVE, NULL);
 426         sys_chroot(".");
 427 }