diff options
Diffstat (limited to 'init/do_mounts.c')
| -rw-r--r-- | init/do_mounts.c | 430 |
1 files changed, 430 insertions, 0 deletions
diff --git a/init/do_mounts.c b/init/do_mounts.c new file mode 100644 index 00000000000..b7570c074d0 --- /dev/null +++ b/init/do_mounts.c @@ -0,0 +1,430 @@ +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/ctype.h> +#include <linux/fd.h> +#include <linux/tty.h> +#include <linux/suspend.h> +#include <linux/root_dev.h> +#include <linux/security.h> +#include <linux/delay.h> + +#include <linux/nfs_fs.h> +#include <linux/nfs_fs_sb.h> +#include <linux/nfs_mount.h> + +#include "do_mounts.h" + +extern int get_filesystem_list(char * buf); + +int __initdata rd_doload; /* 1 = load RAM disk, 0 = don't load */ + +int root_mountflags = MS_RDONLY | MS_VERBOSE; +char * __initdata root_device_name; +static char __initdata saved_root_name[64]; + +/* this is initialized in init/main.c */ +dev_t ROOT_DEV; + +EXPORT_SYMBOL(ROOT_DEV); + +static int __init load_ramdisk(char *str) +{ + rd_doload = simple_strtol(str,NULL,0) & 3; + return 1; +} +__setup("load_ramdisk=", load_ramdisk); + +static int __init readonly(char *str) +{ + if (*str) + return 0; + root_mountflags |= MS_RDONLY; + return 1; +} + +static int __init readwrite(char *str) +{ + if (*str) + return 0; + root_mountflags &= ~MS_RDONLY; + return 1; +} + +__setup("ro", readonly); +__setup("rw", readwrite); + +static dev_t try_name(char *name, int part) +{ + char path[64]; + char buf[32]; + int range; + dev_t res; + char *s; + int len; + int fd; + unsigned int maj, min; + + /* read device number from .../dev */ + + sprintf(path, "/sys/block/%s/dev", name); + fd = sys_open(path, 0, 0); + if (fd < 0) + goto fail; + len = sys_read(fd, buf, 32); + sys_close(fd); + if (len <= 0 || len == 32 || buf[len - 1] != '\n') + goto fail; + buf[len - 1] = '\0'; + if (sscanf(buf, "%u:%u", &maj, &min) == 2) { + /* + * Try the %u:%u format -- see print_dev_t() + */ + res = MKDEV(maj, min); + if (maj != MAJOR(res) || min != MINOR(res)) + goto fail; + } else { + /* + * Nope. Try old-style "0321" + */ + res = new_decode_dev(simple_strtoul(buf, &s, 16)); + if (*s) + goto fail; + } + + /* if it's there and we are not looking for a partition - that's it */ + if (!part) + return res; + + /* otherwise read range from .../range */ + sprintf(path, "/sys/block/%s/range", name); + fd = sys_open(path, 0, 0); + if (fd < 0) + goto fail; + len = sys_read(fd, buf, 32); + sys_close(fd); + if (len <= 0 || len == 32 || buf[len - 1] != '\n') + goto fail; + buf[len - 1] = '\0'; + range = simple_strtoul(buf, &s, 10); + if (*s) + goto fail; + + /* if partition is within range - we got it */ + if (part < range) + return res + part; +fail: + return 0; +} + +/* + * Convert a name into device number. We accept the following variants: + * + * 1) device number in hexadecimal represents itself + * 2) /dev/nfs represents Root_NFS (0xff) + * 3) /dev/<disk_name> represents the device number of disk + * 4) /dev/<disk_name><decimal> represents the device number + * of partition - device number of disk plus the partition number + * 5) /dev/<disk_name>p<decimal> - same as the above, that form is + * used when disk name of partitioned disk ends on a digit. + * + * If name doesn't have fall into the categories above, we return 0. + * Driverfs is used to check if something is a disk name - it has + * all known disks under bus/block/devices. If the disk name + * contains slashes, name of driverfs node has them replaced with + * bangs. try_name() does the actual checks, assuming that driverfs + * is mounted on rootfs /sys. + */ + +dev_t name_to_dev_t(char *name) +{ + char s[32]; + char *p; + dev_t res = 0; + int part; + +#ifdef CONFIG_SYSFS + int mkdir_err = sys_mkdir("/sys", 0700); + if (sys_mount("sysfs", "/sys", "sysfs", 0, NULL) < 0) + goto out; +#endif + + if (strncmp(name, "/dev/", 5) != 0) { + unsigned maj, min; + + if (sscanf(name, "%u:%u", &maj, &min) == 2) { + res = MKDEV(maj, min); + if (maj != MAJOR(res) || min != MINOR(res)) + goto fail; + } else { + res = new_decode_dev(simple_strtoul(name, &p, 16)); + if (*p) + goto fail; + } + goto done; + } + name += 5; + res = Root_NFS; + if (strcmp(name, "nfs") == 0) + goto done; + res = Root_RAM0; + if (strcmp(name, "ram") == 0) + goto done; + + if (strlen(name) > 31) + goto fail; + strcpy(s, name); + for (p = s; *p; p++) + if (*p == '/') + *p = '!'; + res = try_name(s, 0); + if (res) + goto done; + + while (p > s && isdigit(p[-1])) + p--; + if (p == s || !*p || *p == '0') + goto fail; + part = simple_strtoul(p, NULL, 10); + *p = '\0'; + res = try_name(s, part); + if (res) + goto done; + + if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p') + goto fail; + p[-1] = '\0'; + res = try_name(s, part); +done: +#ifdef CONFIG_SYSFS + sys_umount("/sys", 0); +out: + if (!mkdir_err) + sys_rmdir("/sys"); +#endif + return res; +fail: + res = 0; + goto done; +} + +static int __init root_dev_setup(char *line) +{ + strlcpy(saved_root_name, line, sizeof(saved_root_name)); + return 1; +} + +__setup("root=", root_dev_setup); + +static char * __initdata root_mount_data; +static int __init root_data_setup(char *str) +{ + root_mount_data = str; + return 1; +} + +static char * __initdata root_fs_names; +static int __init fs_names_setup(char *str) +{ + root_fs_names = str; + return 1; +} + +static unsigned int __initdata root_delay; +static int __init root_delay_setup(char *str) +{ + root_delay = simple_strtoul(str, NULL, 0); + return 1; +} + +__setup("rootflags=", root_data_setup); +__setup("rootfstype=", fs_names_setup); +__setup("rootdelay=", root_delay_setup); + +static void __init get_fs_names(char *page) +{ + char *s = page; + + if (root_fs_names) { + strcpy(page, root_fs_names); + while (*s++) { + if (s[-1] == ',') + s[-1] = '\0'; + } + } else { + int len = get_filesystem_list(page); + char *p, *next; + + page[len] = '\0'; + for (p = page-1; p; p = next) { + next = strchr(++p, '\n'); + if (*p++ != '\t') + continue; + while ((*s++ = *p++) != '\n') + ; + s[-1] = '\0'; + } + } + *s = '\0'; +} + +static int __init do_mount_root(char *name, char *fs, int flags, void *data) +{ + int err = sys_mount(name, "/root", fs, flags, data); + if (err) + return err; + + sys_chdir("/root"); + ROOT_DEV = current->fs->pwdmnt->mnt_sb->s_dev; + printk("VFS: Mounted root (%s filesystem)%s.\n", + current->fs->pwdmnt->mnt_sb->s_type->name, + current->fs->pwdmnt->mnt_sb->s_flags & MS_RDONLY ? + " readonly" : ""); + return 0; +} + +void __init mount_block_root(char *name, int flags) +{ + char *fs_names = __getname(); + char *p; + char b[BDEVNAME_SIZE]; + + get_fs_names(fs_names); +retry: + for (p = fs_names; *p; p += strlen(p)+1) { + int err = do_mount_root(name, p, flags, root_mount_data); + switch (err) { + case 0: + goto out; + case -EACCES: + flags |= MS_RDONLY; + goto retry; + case -EINVAL: + continue; + } + /* + * Allow the user to distinguish between failed sys_open + * and bad superblock on root device. + */ + __bdevname(ROOT_DEV, b); + printk("VFS: Cannot open root device \"%s\" or %s\n", + root_device_name, b); + printk("Please append a correct \"root=\" boot option\n"); + + panic("VFS: Unable to mount root fs on %s", b); + } + panic("VFS: Unable to mount root fs on %s", __bdevname(ROOT_DEV, b)); +out: + putname(fs_names); +} + +#ifdef CONFIG_ROOT_NFS +static int __init mount_nfs_root(void) +{ + void *data = nfs_root_data(); + + create_dev("/dev/root", ROOT_DEV, NULL); + if (data && + do_mount_root("/dev/root", "nfs", root_mountflags, data) == 0) + return 1; + return 0; +} +#endif + +#if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD) +void __init change_floppy(char *fmt, ...) +{ + struct termios termios; + char buf[80]; + char c; + int fd; + va_list args; + va_start(args, fmt); + vsprintf(buf, fmt, args); + va_end(args); + fd = sys_open("/dev/root", O_RDWR | O_NDELAY, 0); + if (fd >= 0) { + sys_ioctl(fd, FDEJECT, 0); + sys_close(fd); + } + printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf); + fd = sys_open("/dev/console", O_RDWR, 0); + if (fd >= 0) { + sys_ioctl(fd, TCGETS, (long)&termios); + termios.c_lflag &= ~ICANON; + sys_ioctl(fd, TCSETSF, (long)&termios); + sys_read(fd, &c, 1); + termios.c_lflag |= ICANON; + sys_ioctl(fd, TCSETSF, (long)&termios); + sys_close(fd); + } +} +#endif + +void __init mount_root(void) +{ +#ifdef CONFIG_ROOT_NFS + if (MAJOR(ROOT_DEV) == UNNAMED_MAJOR) { + if (mount_nfs_root()) + return; + + printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n"); + ROOT_DEV = Root_FD0; + } +#endif +#ifdef CONFIG_BLK_DEV_FD + if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) { + /* rd_doload is 2 for a dual initrd/ramload setup */ + if (rd_doload==2) { + if (rd_load_disk(1)) { + ROOT_DEV = Root_RAM1; + root_device_name = NULL; + } + } else + change_floppy("root floppy"); + } +#endif + create_dev("/dev/root", ROOT_DEV, root_device_name); + mount_block_root("/dev/root", root_mountflags); +} + +/* + * Prepare the namespace - decide what/where to mount, load ramdisks, etc. + */ +void __init prepare_namespace(void) +{ + int is_floppy; + + mount_devfs(); + + if (root_delay) { + printk(KERN_INFO "Waiting %dsec before mounting root device...\n", + root_delay); + ssleep(root_delay); + } + + md_run_setup(); + + if (saved_root_name[0]) { + root_device_name = saved_root_name; + ROOT_DEV = name_to_dev_t(root_device_name); + if (strncmp(root_device_name, "/dev/", 5) == 0) + root_device_name += 5; + } + + is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR; + + if (initrd_load()) + goto out; + + if (is_floppy && rd_doload && rd_load_disk(0)) + ROOT_DEV = Root_RAM0; + + mount_root(); +out: + umount_devfs("/dev"); + sys_mount(".", "/", NULL, MS_MOVE, NULL); + sys_chroot("."); + security_sb_post_mountroot(); + mount_devfs_fs (); +} + |