[RFC,66/68] vfs: Convert ubifs to use the new mount API

diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 8dc2818fdd84..e77ad4dd2665 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -31,9 +31,9 @@ 
 #include <linux/module.h>
 #include <linux/ctype.h>
 #include <linux/kthread.h>
-#include <linux/parser.h>
+#include <linux/fs_context.h>
+#include <linux/fs_parser.h>
 #include <linux/seq_file.h>
-#include <linux/mount.h>
 #include <linux/math64.h>
 #include <linux/writeback.h>
 #include "ubifs.h"
@@ -935,7 +935,7 @@  static int check_volume_empty(struct ubifs_info *c)
  * Opt_no_bulk_read: disable bulk-reads
  * Opt_chk_data_crc: check CRCs when reading data nodes
  * Opt_no_chk_data_crc: do not check CRCs when reading data nodes
- * Opt_override_compr: override default compressor
+ * Opt_compr: override default compressor
  * Opt_assert: set ubifs_assert() action
  * Opt_auth_key: The key name used for authentication
  * Opt_auth_hash_name: The hash type used for authentication
@@ -948,54 +948,47 @@  enum {
 	Opt_no_bulk_read,
 	Opt_chk_data_crc,
 	Opt_no_chk_data_crc,
-	Opt_override_compr,
+	Opt_compr,
 	Opt_assert,
 	Opt_auth_key,
 	Opt_auth_hash_name,
 	Opt_ignore,
-	Opt_err,
 };
 
-static const match_table_t tokens = {
-	{Opt_fast_unmount, "fast_unmount"},
-	{Opt_norm_unmount, "norm_unmount"},
-	{Opt_bulk_read, "bulk_read"},
-	{Opt_no_bulk_read, "no_bulk_read"},
-	{Opt_chk_data_crc, "chk_data_crc"},
-	{Opt_no_chk_data_crc, "no_chk_data_crc"},
-	{Opt_override_compr, "compr=%s"},
-	{Opt_auth_key, "auth_key=%s"},
-	{Opt_auth_hash_name, "auth_hash_name=%s"},
-	{Opt_ignore, "ubi=%s"},
-	{Opt_ignore, "vol=%s"},
-	{Opt_assert, "assert=%s"},
-	{Opt_err, NULL},
+static const struct fs_parameter_spec ubifs_param_specs[] = {
+	fsparam_flag	("fast_unmount",		Opt_fast_unmount),
+	fsparam_flag	("norm_unmount",		Opt_norm_unmount),
+	fsparam_flag	("bulk_read",			Opt_bulk_read),
+	fsparam_flag	("no_bulk_read",		Opt_no_bulk_read),
+	fsparam_flag	("chk_data_crc",		Opt_chk_data_crc),
+	fsparam_flag	("no_chk_data_crc",		Opt_no_chk_data_crc),
+	fsparam_enum	("compr",			Opt_compr),
+	fsparam_enum	("assert",			Opt_assert),
+	fsparam_string	("auth_key",			Opt_auth_key),
+	fsparam_string	("auth_hash_name",		Opt_auth_hash_name),
+	fsparam_string	("ubi",				Opt_ignore),
+	fsparam_string	("vol",				Opt_ignore),
+	{}
 };
 
-/**
- * parse_standard_option - parse a standard mount option.
- * @option: the option to parse
- *
- * Normally, standard mount options like "sync" are passed to file-systems as
- * flags. However, when a "rootflags=" kernel boot parameter is used, they may
- * be present in the options string. This function tries to deal with this
- * situation and parse standard options. Returns 0 if the option was not
- * recognized, and the corresponding integer flag if it was.
- *
- * UBIFS is only interested in the "sync" option, so do not check for anything
- * else.
- */
-static int parse_standard_option(const char *option)
-{
+static const struct fs_parameter_enum ubifs_param_enums[] = {
+	{ Opt_compr,	"none",		UBIFS_COMPR_NONE },
+	{ Opt_compr,	"lzo",		UBIFS_COMPR_LZO },
+	{ Opt_compr,	"zlib",		UBIFS_COMPR_ZLIB },
+	{ Opt_assert,	"report",	ASSACT_REPORT },
+	{ Opt_assert,	"read-only",	ASSACT_RO },
+	{ Opt_assert,	"panic",	ASSACT_PANIC },
+	{}
+};
 
-	pr_notice("UBIFS: parse %s\n", option);
-	if (!strcmp(option, "sync"))
-		return SB_SYNCHRONOUS;
-	return 0;
-}
+static const struct fs_parameter_description ubifs_fs_parameters = {
+	.name		= "ubifs",
+	.specs		= ubifs_param_specs,
+	.enums		= ubifs_param_enums,
+};
 
 /**
- * ubifs_parse_options - parse mount parameters.
+ * ubifs_parse_param - parse a parameter.
  * @c: UBIFS file-system description object
  * @options: parameters to parse
  * @is_remount: non-zero if this is FS re-mount
@@ -1003,119 +996,64 @@  static int parse_standard_option(const char *option)
  * This function parses UBIFS mount options and returns zero in case success
  * and a negative error code in case of failure.
  */
-static int ubifs_parse_options(struct ubifs_info *c, char *options,
-			       int is_remount)
+static int ubifs_parse_param(struct fs_context *fc, struct fs_parameter *param)
 {
-	char *p;
-	substring_t args[MAX_OPT_ARGS];
-
-	if (!options)
-		return 0;
-
-	while ((p = strsep(&options, ","))) {
-		int token;
+	struct ubifs_info *c = fc->s_fs_info;
+	struct fs_parse_result result;
+	int opt;
 
-		if (!*p)
-			continue;
+	opt = fs_parse(fc, &ubifs_fs_parameters, param, &result);
+	if (opt < 0)
+		return opt;
 
-		token = match_token(p, tokens, args);
-		switch (token) {
+	switch (opt) {
 		/*
 		 * %Opt_fast_unmount and %Opt_norm_unmount options are ignored.
 		 * We accept them in order to be backward-compatible. But this
 		 * should be removed at some point.
 		 */
-		case Opt_fast_unmount:
-			c->mount_opts.unmount_mode = 2;
-			break;
-		case Opt_norm_unmount:
-			c->mount_opts.unmount_mode = 1;
-			break;
-		case Opt_bulk_read:
-			c->mount_opts.bulk_read = 2;
-			c->bulk_read = 1;
-			break;
-		case Opt_no_bulk_read:
-			c->mount_opts.bulk_read = 1;
-			c->bulk_read = 0;
-			break;
-		case Opt_chk_data_crc:
-			c->mount_opts.chk_data_crc = 2;
-			c->no_chk_data_crc = 0;
-			break;
-		case Opt_no_chk_data_crc:
-			c->mount_opts.chk_data_crc = 1;
-			c->no_chk_data_crc = 1;
-			break;
-		case Opt_override_compr:
-		{
-			char *name = match_strdup(&args[0]);
-
-			if (!name)
-				return -ENOMEM;
-			if (!strcmp(name, "none"))
-				c->mount_opts.compr_type = UBIFS_COMPR_NONE;
-			else if (!strcmp(name, "lzo"))
-				c->mount_opts.compr_type = UBIFS_COMPR_LZO;
-			else if (!strcmp(name, "zlib"))
-				c->mount_opts.compr_type = UBIFS_COMPR_ZLIB;
-			else {
-				ubifs_err(c, "unknown compressor \"%s\"", name); //FIXME: is c ready?
-				kfree(name);
-				return -EINVAL;
-			}
-			kfree(name);
-			c->mount_opts.override_compr = 1;
-			c->default_compr = c->mount_opts.compr_type;
-			break;
-		}
-		case Opt_assert:
-		{
-			char *act = match_strdup(&args[0]);
-
-			if (!act)
-				return -ENOMEM;
-			if (!strcmp(act, "report"))
-				c->assert_action = ASSACT_REPORT;
-			else if (!strcmp(act, "read-only"))
-				c->assert_action = ASSACT_RO;
-			else if (!strcmp(act, "panic"))
-				c->assert_action = ASSACT_PANIC;
-			else {
-				ubifs_err(c, "unknown assert action \"%s\"", act);
-				kfree(act);
-				return -EINVAL;
-			}
-			kfree(act);
-			break;
-		}
-		case Opt_auth_key:
-			c->auth_key_name = kstrdup(args[0].from, GFP_KERNEL);
-			if (!c->auth_key_name)
-				return -ENOMEM;
-			break;
-		case Opt_auth_hash_name:
-			c->auth_hash_name = kstrdup(args[0].from, GFP_KERNEL);
-			if (!c->auth_hash_name)
-				return -ENOMEM;
-			break;
-		case Opt_ignore:
-			break;
-		default:
-		{
-			unsigned long flag;
-			struct super_block *sb = c->vfs_sb;
-
-			flag = parse_standard_option(p);
-			if (!flag) {
-				ubifs_err(c, "unrecognized mount option \"%s\" or missing value",
-					  p);
-				return -EINVAL;
-			}
-			sb->s_flags |= flag;
-			break;
-		}
-		}
+	case Opt_fast_unmount:
+		c->mount_opts.unmount_mode = 2;
+		break;
+	case Opt_norm_unmount:
+		c->mount_opts.unmount_mode = 1;
+		break;
+	case Opt_bulk_read:
+		c->mount_opts.bulk_read = 2;
+		c->bulk_read = 1;
+		break;
+	case Opt_no_bulk_read:
+		c->mount_opts.bulk_read = 1;
+		c->bulk_read = 0;
+		break;
+	case Opt_chk_data_crc:
+		c->mount_opts.chk_data_crc = 2;
+		c->no_chk_data_crc = 0;
+		break;
+	case Opt_no_chk_data_crc:
+		c->mount_opts.chk_data_crc = 1;
+		c->no_chk_data_crc = 1;
+		break;
+	case Opt_compr:
+		c->mount_opts.compr_type = result.uint_32;
+		c->mount_opts.override_compr = 1;
+		c->default_compr = c->mount_opts.compr_type;
+		break;
+	case Opt_assert:
+		c->assert_action = result.uint_32;
+		break;
+	case Opt_auth_key:
+		kfree(c->auth_key_name);
+		c->auth_key_name = param->string;
+		param->string = NULL;
+		break;
+	case Opt_auth_hash_name:
+		kfree(c->auth_hash_name);
+		c->auth_hash_name = param->string;
+		param->string = NULL;
+		break;
+	case Opt_ignore:
+		break;
 	}
 
 	return 0;
@@ -1927,21 +1865,30 @@  static void ubifs_put_super(struct super_block *sb)
 	mutex_unlock(&c->umount_mutex);
 }
 
-static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
+static int ubifs_reconfigure(struct fs_context *fc)
 {
+	struct super_block *sb = fc->root->d_sb;
 	int err;
 	struct ubifs_info *c = sb->s_fs_info;
+	struct ubifs_info *reconf = fc->s_fs_info;
 
 	sync_filesystem(sb);
-	dbg_gen("old flags %#lx, new flags %#x", sb->s_flags, *flags);
+	dbg_gen("old flags %#lx, new flags %#x", sb->s_flags, fc->sb_flags);
 
-	err = ubifs_parse_options(c, data, 1);
-	if (err) {
-		ubifs_err(c, "invalid or unknown remount parameter");
-		return err;
-	}
+	/* Apply the mount option changes.
+	 *
+	 * [!] NOTE Replacing the auth_key_name and auth_hash_name is
+	 *     very dodgy without locking.  Previously it just leaked
+	 *     the old strings.  The strings only seem to be used
+	 *     during mounting, so don't reconfigure those.
+	 */
+	c->mount_opts		= reconf->mount_opts;
+	c->bulk_read		= reconf->bulk_read;
+	c->no_chk_data_crc	= reconf->no_chk_data_crc;
+	c->default_compr	= reconf->default_compr;
+	c->assert_action	= reconf->assert_action;
 
-	if (c->ro_mount && !(*flags & SB_RDONLY)) {
+	if (c->ro_mount && !(fc->sb_flags & SB_RDONLY)) {
 		if (c->ro_error) {
 			ubifs_msg(c, "cannot re-mount R/W due to prior errors");
 			return -EROFS;
@@ -1953,7 +1900,7 @@  static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
 		err = ubifs_remount_rw(c);
 		if (err)
 			return err;
-	} else if (!c->ro_mount && (*flags & SB_RDONLY)) {
+	} else if (!c->ro_mount && (fc->sb_flags & SB_RDONLY)) {
 		if (c->ro_error) {
 			ubifs_msg(c, "cannot re-mount R/O due to prior errors");
 			return -EROFS;
@@ -1985,14 +1932,13 @@  const struct super_operations ubifs_super_operations = {
 	.evict_inode   = ubifs_evict_inode,
 	.statfs        = ubifs_statfs,
 	.dirty_inode   = ubifs_dirty_inode,
-	.remount_fs    = ubifs_remount_fs,
 	.show_options  = ubifs_show_options,
 	.sync_fs       = ubifs_sync_fs,
 };
 
 /**
  * open_ubi - parse UBI device name string and open the UBI device.
- * @name: UBI volume name
+ * @fc: The filesystem parameters
  * @mode: UBI volume open mode
  *
  * The primary method of mounting UBIFS is by specifying the UBI volume
@@ -2009,15 +1955,13 @@  const struct super_operations ubifs_super_operations = {
  * returns UBI volume description object in case of success and a negative
  * error code in case of failure.
  */
-static struct ubi_volume_desc *open_ubi(const char *name, int mode)
+static struct ubi_volume_desc *open_ubi(struct fs_context *fc, int mode)
 {
 	struct ubi_volume_desc *ubi;
+	const char *name = fc->source;
 	int dev, vol;
 	char *endptr;
 
-	if (!name || !*name)
-		return ERR_PTR(-EINVAL);
-
 	/* First, try to open using the device node path method */
 	ubi = ubi_open_volume_path(name, mode);
 	if (!IS_ERR(ubi))
@@ -2025,14 +1969,14 @@  static struct ubi_volume_desc *open_ubi(const char *name, int mode)
 
 	/* Try the "nodev" method */
 	if (name[0] != 'u' || name[1] != 'b' || name[2] != 'i')
-		return ERR_PTR(-EINVAL);
+		goto invalid_source;
 
 	/* ubi:NAME method */
 	if ((name[3] == ':' || name[3] == '!') && name[4] != '\0')
 		return ubi_open_volume_nm(0, name + 4, mode);
 
 	if (!isdigit(name[3]))
-		return ERR_PTR(-EINVAL);
+		goto invalid_source;
 
 	dev = simple_strtoul(name + 3, &endptr, 0);
 
@@ -2044,7 +1988,7 @@  static struct ubi_volume_desc *open_ubi(const char *name, int mode)
 	if (*endptr == '_' && isdigit(endptr[1])) {
 		vol = simple_strtoul(endptr + 1, &endptr, 0);
 		if (*endptr != '\0')
-			return ERR_PTR(-EINVAL);
+			goto invalid_source;
 		return ubi_open_volume(dev, vol, mode);
 	}
 
@@ -2052,57 +1996,11 @@  static struct ubi_volume_desc *open_ubi(const char *name, int mode)
 	if ((*endptr == ':' || *endptr == '!') && endptr[1] != '\0')
 		return ubi_open_volume_nm(dev, ++endptr, mode);
 
-	return ERR_PTR(-EINVAL);
-}
-
-static struct ubifs_info *alloc_ubifs_info(struct ubi_volume_desc *ubi)
-{
-	struct ubifs_info *c;
-
-	c = kzalloc(sizeof(struct ubifs_info), GFP_KERNEL);
-	if (c) {
-		spin_lock_init(&c->cnt_lock);
-		spin_lock_init(&c->cs_lock);
-		spin_lock_init(&c->buds_lock);
-		spin_lock_init(&c->space_lock);
-		spin_lock_init(&c->orphan_lock);
-		init_rwsem(&c->commit_sem);
-		mutex_init(&c->lp_mutex);
-		mutex_init(&c->tnc_mutex);
-		mutex_init(&c->log_mutex);
-		mutex_init(&c->umount_mutex);
-		mutex_init(&c->bu_mutex);
-		mutex_init(&c->write_reserve_mutex);
-		init_waitqueue_head(&c->cmt_wq);
-		c->buds = RB_ROOT;
-		c->old_idx = RB_ROOT;
-		c->size_tree = RB_ROOT;
-		c->orph_tree = RB_ROOT;
-		INIT_LIST_HEAD(&c->infos_list);
-		INIT_LIST_HEAD(&c->idx_gc);
-		INIT_LIST_HEAD(&c->replay_list);
-		INIT_LIST_HEAD(&c->replay_buds);
-		INIT_LIST_HEAD(&c->uncat_list);
-		INIT_LIST_HEAD(&c->empty_list);
-		INIT_LIST_HEAD(&c->freeable_list);
-		INIT_LIST_HEAD(&c->frdi_idx_list);
-		INIT_LIST_HEAD(&c->unclean_leb_list);
-		INIT_LIST_HEAD(&c->old_buds);
-		INIT_LIST_HEAD(&c->orph_list);
-		INIT_LIST_HEAD(&c->orph_new);
-		c->no_chk_data_crc = 1;
-		c->assert_action = ASSACT_RO;
-
-		c->highest_inum = UBIFS_FIRST_INO;
-		c->lhead_lnum = c->ltail_lnum = UBIFS_LOG_LNUM;
-
-		ubi_get_volume_info(ubi, &c->vi);
-		ubi_get_device_info(c->vi.ubi_num, &c->di);
-	}
-	return c;
+invalid_source:
+	return ERR_PTR(invalf(fc, "Invalid source name"));
 }
 
-static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
+static int ubifs_fill_super(struct super_block *sb, struct fs_context *fc)
 {
 	struct ubifs_info *c = sb->s_fs_info;
 	struct inode *root;
@@ -2116,10 +2014,6 @@  static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
 		goto out;
 	}
 
-	err = ubifs_parse_options(c, data, 0);
-	if (err)
-		goto out_close;
-
 	/*
 	 * UBIFS provides 'backing_dev_info' in order to disable read-ahead. For
 	 * UBIFS, I/O is not deferred, it is done immediately in readpage,
@@ -2183,69 +2077,61 @@  static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
 	return err;
 }
 
-static int sb_test(struct super_block *sb, void *data)
+static int sb_test(struct super_block *sb, struct fs_context *fc)
 {
-	struct ubifs_info *c1 = data;
+	struct ubifs_info *c1 = fc->s_fs_info;
 	struct ubifs_info *c = sb->s_fs_info;
 
 	return c->vi.cdev == c1->vi.cdev;
 }
 
-static int sb_set(struct super_block *sb, void *data)
-{
-	sb->s_fs_info = data;
-	return set_anon_super(sb, NULL);
-}
-
-static struct dentry *ubifs_mount(struct file_system_type *fs_type, int flags,
-			const char *name, void *data)
+static int ubifs_get_tree(struct fs_context *fc)
 {
 	struct ubi_volume_desc *ubi;
-	struct ubifs_info *c;
+	struct ubifs_info *c = fc->s_fs_info;
 	struct super_block *sb;
 	int err;
 
-	dbg_gen("name %s, flags %#x", name, flags);
+	if (!fc->source || !*fc->source)
+		return invalf(fc, "No source specified");
+
+	dbg_gen("name %s, flags %#x", fc->source, fc->sb_flags);
 
 	/*
 	 * Get UBI device number and volume ID. Mount it read-only so far
 	 * because this might be a new mount point, and UBI allows only one
 	 * read-write user at a time.
 	 */
-	ubi = open_ubi(name, UBI_READONLY);
+	ubi = open_ubi(fc, UBI_READONLY);
 	if (IS_ERR(ubi)) {
-		if (!(flags & SB_SILENT))
-			pr_err("UBIFS error (pid: %d): cannot open \"%s\", error %d",
-			       current->pid, name, (int)PTR_ERR(ubi));
-		return ERR_CAST(ubi);
+		err = PTR_ERR(ubi);
+		if (!(fc->sb_flags & SB_SILENT))
+			errorf(fc, "UBIFS error (pid: %d): cannot open \"%s\", error %d",
+			       current->pid, fc->source, err);
+		return err;
 	}
 
-	c = alloc_ubifs_info(ubi);
-	if (!c) {
-		err = -ENOMEM;
-		goto out_close;
-	}
+	ubi_get_volume_info(ubi, &c->vi);
+	ubi_get_device_info(c->vi.ubi_num, &c->di);
 
 	dbg_gen("opened ubi%d_%d", c->vi.ubi_num, c->vi.vol_id);
 
-	sb = sget(fs_type, sb_test, sb_set, flags, c);
+	sb = sget_fc(fc, sb_test, set_anon_super_fc);
 	if (IS_ERR(sb)) {
 		err = PTR_ERR(sb);
-		kfree(c);
 		goto out_close;
 	}
 
 	if (sb->s_root) {
-		struct ubifs_info *c1 = sb->s_fs_info;
-		kfree(c);
 		/* A new mount point for already mounted UBIFS */
+		c = sb->s_fs_info;
 		dbg_gen("this ubi volume is already mounted");
-		if (!!(flags & SB_RDONLY) != c1->ro_mount) {
+		if (!!(fc->sb_flags & SB_RDONLY) != c->ro_mount) {
 			err = -EBUSY;
 			goto out_deact;
 		}
 	} else {
-		err = ubifs_fill_super(sb, data, flags & SB_SILENT ? 1 : 0);
+		err = ubifs_fill_super(sb, fc);
 		if (err)
 			goto out_deact;
 		/* We do not support atime */
@@ -2260,13 +2146,79 @@  static struct dentry *ubifs_mount(struct file_system_type *fs_type, int flags,
 	/* 'fill_super()' opens ubi again so we must close it here */
 	ubi_close_volume(ubi);
 
-	return dget(sb->s_root);
+	fc->root = dget(sb->s_root);
+	return 0;
 
 out_deact:
 	deactivate_locked_super(sb);
 out_close:
 	ubi_close_volume(ubi);
-	return ERR_PTR(err);
+	return err;
+}
+
+static void ubifs_free_fc(struct fs_context *fc)
+{
+	struct ubifs_info *c = fc->s_fs_info;
+
+	if (c) {
+		kfree(c->auth_key_name);
+		kfree(c->auth_hash_name);
+		kfree(c);
+	}
+}
+
+static const struct fs_context_operations ubifs_context_ops = {
+	.free		= ubifs_free_fc,
+	.parse_param	= ubifs_parse_param,
+	.get_tree	= ubifs_get_tree,
+	.reconfigure	= ubifs_reconfigure,
+};
+
+static int ubifs_init_fs_context(struct fs_context *fc)
+{
+	struct ubifs_info *c;
+
+	c = kzalloc(sizeof(struct ubifs_info), GFP_KERNEL);
+	if (!c)
+		return -ENOMEM;
+
+	spin_lock_init(&c->cnt_lock);
+	spin_lock_init(&c->cs_lock);
+	spin_lock_init(&c->buds_lock);
+	spin_lock_init(&c->space_lock);
+	spin_lock_init(&c->orphan_lock);
+	init_rwsem(&c->commit_sem);
+	mutex_init(&c->lp_mutex);
+	mutex_init(&c->tnc_mutex);
+	mutex_init(&c->log_mutex);
+	mutex_init(&c->umount_mutex);
+	mutex_init(&c->bu_mutex);
+	mutex_init(&c->write_reserve_mutex);
+	init_waitqueue_head(&c->cmt_wq);
+	c->buds = RB_ROOT;
+	c->old_idx = RB_ROOT;
+	c->size_tree = RB_ROOT;
+	c->orph_tree = RB_ROOT;
+	INIT_LIST_HEAD(&c->infos_list);
+	INIT_LIST_HEAD(&c->idx_gc);
+	INIT_LIST_HEAD(&c->replay_list);
+	INIT_LIST_HEAD(&c->replay_buds);
+	INIT_LIST_HEAD(&c->uncat_list);
+	INIT_LIST_HEAD(&c->empty_list);
+	INIT_LIST_HEAD(&c->freeable_list);
+	INIT_LIST_HEAD(&c->frdi_idx_list);
+	INIT_LIST_HEAD(&c->unclean_leb_list);
+	INIT_LIST_HEAD(&c->old_buds);
+	INIT_LIST_HEAD(&c->orph_list);
+	INIT_LIST_HEAD(&c->orph_new);
+	c->no_chk_data_crc = 1;
+	c->assert_action = ASSACT_RO;
+	c->highest_inum = UBIFS_FIRST_INO;
+	c->lhead_lnum = c->ltail_lnum = UBIFS_LOG_LNUM;
+
+	fc->s_fs_info = c;
+	fc->ops = &ubifs_context_ops;
+	return 0;
 }
 
 static void kill_ubifs_super(struct super_block *s)
@@ -2279,7 +2231,8 @@  static void kill_ubifs_super(struct super_block *s)
 static struct file_system_type ubifs_fs_type = {
 	.name    = "ubifs",
 	.owner   = THIS_MODULE,
-	.mount   = ubifs_mount,
+	.init_fs_context = ubifs_init_fs_context,
+	.parameters	= &ubifs_fs_parameters,
 	.kill_sb = kill_ubifs_super,
 };
 MODULE_ALIAS_FS("ubifs");