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-rw-r--r--init/do_mounts.c430
1 files changed, 430 insertions, 0 deletions
diff --git a/init/do_mounts.c b/init/do_mounts.c
new file mode 100644
index 0000000..b7570c0
--- /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 ();
+}
+
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