Initial import

1 files changed, 645 insertions, 0 deletions

diff --git a/init/do_mounts.c b/init/do_mounts.c
new file mode 100644
index 000000000..047726d4f
--- /dev/null
+++ b/init/do_mounts.c
@@ -0,0 +1,645 @@
+/*
+ * Many of the syscalls used in this file expect some of the arguments
+ * to be __user pointers not __kernel pointers.  To limit the sparse
+ * noise, turn off sparse checking for this file.
+ */
+#ifdef __CHECKER__
+#undef __CHECKER__
+#warning "Sparse checking disabled for this file"
+#endif
+
+#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/genhd.h>
+#include <linux/mount.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/initrd.h>
+#include <linux/async.h>
+#include <linux/fs_struct.h>
+#include <linux/slab.h>
+#include <linux/ramfs.h>
+#include <linux/shmem_fs.h>
+
+#include <linux/nfs_fs.h>
+#include <linux/nfs_fs_sb.h>
+#include <linux/nfs_mount.h>
+
+#include "do_mounts.h"
+
+int __initdata rd_doload;	/* 1 = load RAM disk, 0 = don't load */
+
+int root_mountflags = MS_RDONLY | MS_SILENT;
+static char * __initdata root_device_name;
+static char __initdata saved_root_name[64];
+static int root_wait;
+
+dev_t 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);
+
+#ifdef CONFIG_BLOCK
+struct uuidcmp {
+	const char *uuid;
+	int len;
+};
+
+/**
+ * match_dev_by_uuid - callback for finding a partition using its uuid
+ * @dev:	device passed in by the caller
+ * @data:	opaque pointer to the desired struct uuidcmp to match
+ *
+ * Returns 1 if the device matches, and 0 otherwise.
+ */
+static int match_dev_by_uuid(struct device *dev, const void *data)
+{
+	const struct uuidcmp *cmp = data;
+	struct hd_struct *part = dev_to_part(dev);
+
+	if (!part->info)
+		goto no_match;
+
+	if (strncasecmp(cmp->uuid, part->info->uuid, cmp->len))
+		goto no_match;
+
+	return 1;
+no_match:
+	return 0;
+}
+
+
+/**
+ * devt_from_partuuid - looks up the dev_t of a partition by its UUID
+ * @uuid_str:	char array containing ascii UUID
+ *
+ * The function will return the first partition which contains a matching
+ * UUID value in its partition_meta_info struct.  This does not search
+ * by filesystem UUIDs.
+ *
+ * If @uuid_str is followed by a "/PARTNROFF=%d", then the number will be
+ * extracted and used as an offset from the partition identified by the UUID.
+ *
+ * Returns the matching dev_t on success or 0 on failure.
+ */
+static dev_t devt_from_partuuid(const char *uuid_str)
+{
+	dev_t res = 0;
+	struct uuidcmp cmp;
+	struct device *dev = NULL;
+	struct gendisk *disk;
+	struct hd_struct *part;
+	int offset = 0;
+	bool clear_root_wait = false;
+	char *slash;
+
+	cmp.uuid = uuid_str;
+
+	slash = strchr(uuid_str, '/');
+	/* Check for optional partition number offset attributes. */
+	if (slash) {
+		char c = 0;
+		/* Explicitly fail on poor PARTUUID syntax. */
+		if (sscanf(slash + 1,
+			   "PARTNROFF=%d%c", &offset, &c) != 1) {
+			clear_root_wait = true;
+			goto done;
+		}
+		cmp.len = slash - uuid_str;
+	} else {
+		cmp.len = strlen(uuid_str);
+	}
+
+	if (!cmp.len) {
+		clear_root_wait = true;
+		goto done;
+	}
+
+	dev = class_find_device(&block_class, NULL, &cmp,
+				&match_dev_by_uuid);
+	if (!dev)
+		goto done;
+
+	res = dev->devt;
+
+	/* Attempt to find the partition by offset. */
+	if (!offset)
+		goto no_offset;
+
+	res = 0;
+	disk = part_to_disk(dev_to_part(dev));
+	part = disk_get_part(disk, dev_to_part(dev)->partno + offset);
+	if (part) {
+		res = part_devt(part);
+		put_device(part_to_dev(part));
+	}
+
+no_offset:
+	put_device(dev);
+done:
+	if (clear_root_wait) {
+		pr_err("VFS: PARTUUID= is invalid.\n"
+		       "Expected PARTUUID=<valid-uuid-id>[/PARTNROFF=%%d]\n");
+		if (root_wait)
+			pr_err("Disabling rootwait; root= is invalid.\n");
+		root_wait = 0;
+	}
+	return res;
+}
+#endif
+
+/*
+ *	Convert a name into device number.  We accept the following variants:
+ *
+ *	1) <hex_major><hex_minor> device number in hexadecimal represents itself
+ *         no leading 0x, for example b302.
+ *	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.
+ *	6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the
+ *	   unique id of a partition if the partition table provides it.
+ *	   The UUID may be either an EFI/GPT UUID, or refer to an MSDOS
+ *	   partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero-
+ *	   filled hex representation of the 32-bit "NT disk signature", and PP
+ *	   is a zero-filled hex representation of the 1-based partition number.
+ *	7) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation to
+ *	   a partition with a known unique id.
+ *	8) <major>:<minor> major and minor number of the device separated by
+ *	   a colon.
+ *
+ *	If name doesn't have fall into the categories above, we return (0,0).
+ *	block_class is used to check if something is a disk name. If the disk
+ *	name contains slashes, the device name has them replaced with
+ *	bangs.
+ */
+
+dev_t name_to_dev_t(const char *name)
+{
+	char s[32];
+	char *p;
+	dev_t res = 0;
+	int part;
+
+#ifdef CONFIG_BLOCK
+	if (strncmp(name, "PARTUUID=", 9) == 0) {
+		name += 9;
+		res = devt_from_partuuid(name);
+		if (!res)
+			goto fail;
+		goto done;
+	}
+#endif
+
+	if (strncmp(name, "/dev/", 5) != 0) {
+		unsigned maj, min, offset;
+		char dummy;
+
+		if ((sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2) ||
+		    (sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset, &dummy) == 3)) {
+			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 = blk_lookup_devt(s, 0);
+	if (res)
+		goto done;
+
+	/*
+	 * try non-existent, but valid partition, which may only exist
+	 * after revalidating the disk, like partitioned md devices
+	 */
+	while (p > s && isdigit(p[-1]))
+		p--;
+	if (p == s || !*p || *p == '0')
+		goto fail;
+
+	/* try disk name without <part number> */
+	part = simple_strtoul(p, NULL, 10);
+	*p = '\0';
+	res = blk_lookup_devt(s, part);
+	if (res)
+		goto done;
+
+	/* try disk name without p<part number> */
+	if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
+		goto fail;
+	p[-1] = '\0';
+	res = blk_lookup_devt(s, part);
+	if (res)
+		goto done;
+
+fail:
+	return 0;
+done:
+	return res;
+}
+EXPORT_SYMBOL_GPL(name_to_dev_t);
+
+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 int __init rootwait_setup(char *str)
+{
+	if (*str)
+		return 0;
+	root_wait = 1;
+	return 1;
+}
+
+__setup("rootwait", rootwait_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)
+{
+	struct super_block *s;
+	int err = sys_mount(name, "/root", fs, flags, data);
+	if (err)
+		return err;
+
+	sys_chdir("/root");
+	s = current->fs->pwd.dentry->d_sb;
+	ROOT_DEV = s->s_dev;
+	printk(KERN_INFO
+	       "VFS: Mounted root (%s filesystem)%s on device %u:%u.\n",
+	       s->s_type->name,
+	       s->s_flags & MS_RDONLY ?  " readonly" : "",
+	       MAJOR(ROOT_DEV), MINOR(ROOT_DEV));
+	return 0;
+}
+
+void __init mount_block_root(char *name, int flags)
+{
+	struct page *page = alloc_page(GFP_KERNEL |
+					__GFP_NOTRACK_FALSE_POSITIVE);
+	char *fs_names = page_address(page);
+	char *p;
+#ifdef CONFIG_BLOCK
+	char b[BDEVNAME_SIZE];
+#else
+	const char *b = name;
+#endif
+
+	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:
+			case -EINVAL:
+				continue;
+		}
+	        /*
+		 * Allow the user to distinguish between failed sys_open
+		 * and bad superblock on root device.
+		 * and give them a list of the available devices
+		 */
+#ifdef CONFIG_BLOCK
+		__bdevname(ROOT_DEV, b);
+#endif
+		printk("VFS: Cannot open root device \"%s\" or %s: error %d\n",
+				root_device_name, b, err);
+		printk("Please append a correct \"root=\" boot option; here are the available partitions:\n");
+
+		printk_all_partitions();
+#ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
+		printk("DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify "
+		       "explicit textual name for \"root=\" boot option.\n");
+#endif
+		panic("VFS: Unable to mount root fs on %s", b);
+	}
+	if (!(flags & MS_RDONLY)) {
+		flags |= MS_RDONLY;
+		goto retry;
+	}
+
+	printk("List of all partitions:\n");
+	printk_all_partitions();
+	printk("No filesystem could mount root, tried: ");
+	for (p = fs_names; *p; p += strlen(p)+1)
+		printk(" %s", p);
+	printk("\n");
+#ifdef CONFIG_BLOCK
+	__bdevname(ROOT_DEV, b);
+#endif
+	panic("VFS: Unable to mount root fs on %s", b);
+out:
+	put_page(page);
+}
+ 
+#ifdef CONFIG_ROOT_NFS
+
+#define NFSROOT_TIMEOUT_MIN	5
+#define NFSROOT_TIMEOUT_MAX	30
+#define NFSROOT_RETRY_MAX	5
+
+static int __init mount_nfs_root(void)
+{
+	char *root_dev, *root_data;
+	unsigned int timeout;
+	int try, err;
+
+	err = nfs_root_data(&root_dev, &root_data);
+	if (err != 0)
+		return 0;
+
+	/*
+	 * The server or network may not be ready, so try several
+	 * times.  Stop after a few tries in case the client wants
+	 * to fall back to other boot methods.
+	 */
+	timeout = NFSROOT_TIMEOUT_MIN;
+	for (try = 1; ; try++) {
+		err = do_mount_root(root_dev, "nfs",
+					root_mountflags, root_data);
+		if (err == 0)
+			return 1;
+		if (try > NFSROOT_RETRY_MAX)
+			break;
+
+		/* Wait, in case the server refused us immediately */
+		ssleep(timeout);
+		timeout <<= 1;
+		if (timeout > NFSROOT_TIMEOUT_MAX)
+			timeout = NFSROOT_TIMEOUT_MAX;
+	}
+	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 (ROOT_DEV == Root_NFS) {
+		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
+#ifdef CONFIG_BLOCK
+	create_dev("/dev/root", ROOT_DEV);
+	mount_block_root("/dev/root", root_mountflags);
+#endif
+}
+
+/*
+ * Prepare the namespace - decide what/where to mount, load ramdisks, etc.
+ */
+void __init prepare_namespace(void)
+{
+	int is_floppy;
+
+	if (root_delay) {
+		printk(KERN_INFO "Waiting %d sec before mounting root device...\n",
+		       root_delay);
+		ssleep(root_delay);
+	}
+
+	/*
+	 * wait for the known devices to complete their probing
+	 *
+	 * Note: this is a potential source of long boot delays.
+	 * For example, it is not atypical to wait 5 seconds here
+	 * for the touchpad of a laptop to initialize.
+	 */
+	wait_for_device_probe();
+
+	md_run_setup();
+
+	if (saved_root_name[0]) {
+		root_device_name = saved_root_name;
+		if (!strncmp(root_device_name, "mtd", 3) ||
+		    !strncmp(root_device_name, "ubi", 3)) {
+			mount_block_root(root_device_name, root_mountflags);
+			goto out;
+		}
+		ROOT_DEV = name_to_dev_t(root_device_name);
+		if (strncmp(root_device_name, "/dev/", 5) == 0)
+			root_device_name += 5;
+	}
+
+	if (initrd_load())
+		goto out;
+
+	/* wait for any asynchronous scanning to complete */
+	if ((ROOT_DEV == 0) && root_wait) {
+		printk(KERN_INFO "Waiting for root device %s...\n",
+			saved_root_name);
+		while (driver_probe_done() != 0 ||
+			(ROOT_DEV = name_to_dev_t(saved_root_name)) == 0)
+			msleep(100);
+		async_synchronize_full();
+	}
+
+	is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR;
+
+	if (is_floppy && rd_doload && rd_load_disk(0))
+		ROOT_DEV = Root_RAM0;
+
+	check_resume_attempted();
+
+	mount_root();
+out:
+	devtmpfs_mount("dev");
+	sys_mount(".", "/", NULL, MS_MOVE, NULL);
+	sys_chroot(".");
+}
+
+static bool is_tmpfs;
+static struct dentry *rootfs_mount(struct file_system_type *fs_type,
+	int flags, const char *dev_name, void *data)
+{
+	static unsigned long once;
+	void *fill = ramfs_fill_super;
+
+	if (test_and_set_bit(0, &once))
+		return ERR_PTR(-ENODEV);
+
+	if (IS_ENABLED(CONFIG_TMPFS) && is_tmpfs)
+		fill = shmem_fill_super;
+
+	return mount_nodev(fs_type, flags, data, fill);
+}
+
+static struct file_system_type rootfs_fs_type = {
+	.name		= "rootfs",
+	.mount		= rootfs_mount,
+	.kill_sb	= kill_litter_super,
+};
+
+int __init init_rootfs(void)
+{
+	int err = register_filesystem(&rootfs_fs_type);
+
+	if (err)
+		return err;
+
+	if (IS_ENABLED(CONFIG_TMPFS) && !saved_root_name[0] &&
+		(!root_fs_names || strstr(root_fs_names, "tmpfs"))) {
+		err = shmem_init();
+		is_tmpfs = true;
+	} else {
+		err = init_ramfs_fs();
+	}
+
+	if (err)
+		unregister_filesystem(&rootfs_fs_type);
+
+	return err;
+}