Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c
index 5b68e42..fa4f644 100644
--- a/fs/efivarfs/super.c
+++ b/fs/efivarfs/super.c
@@ -1,15 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (C) 2012 Red Hat, Inc.
  * Copyright (C) 2012 Jeremy Kerr <jeremy.kerr@canonical.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
  */
 
 #include <linux/ctype.h>
 #include <linux/efi.h>
 #include <linux/fs.h>
+#include <linux/fs_context.h>
 #include <linux/module.h>
 #include <linux/pagemap.h>
 #include <linux/ucs2_string.h>
@@ -31,8 +29,6 @@
 	.evict_inode = efivarfs_evict_inode,
 };
 
-static struct super_block *efivarfs_sb;
-
 /*
  * Compare two efivarfs file names.
  *
@@ -191,14 +187,12 @@
 	return 0;
 }
 
-static int efivarfs_fill_super(struct super_block *sb, void *data, int silent)
+static int efivarfs_fill_super(struct super_block *sb, struct fs_context *fc)
 {
 	struct inode *inode = NULL;
 	struct dentry *root;
 	int err;
 
-	efivarfs_sb = sb;
-
 	sb->s_maxbytes          = MAX_LFS_FILESIZE;
 	sb->s_blocksize         = PAGE_SIZE;
 	sb->s_blocksize_bits    = PAGE_SHIFT;
@@ -226,16 +220,24 @@
 	return err;
 }
 
-static struct dentry *efivarfs_mount(struct file_system_type *fs_type,
-				    int flags, const char *dev_name, void *data)
+static int efivarfs_get_tree(struct fs_context *fc)
 {
-	return mount_single(fs_type, flags, data, efivarfs_fill_super);
+	return get_tree_single(fc, efivarfs_fill_super);
+}
+
+static const struct fs_context_operations efivarfs_context_ops = {
+	.get_tree	= efivarfs_get_tree,
+};
+
+static int efivarfs_init_fs_context(struct fs_context *fc)
+{
+	fc->ops = &efivarfs_context_ops;
+	return 0;
 }
 
 static void efivarfs_kill_sb(struct super_block *sb)
 {
 	kill_litter_super(sb);
-	efivarfs_sb = NULL;
 
 	/* Remove all entries and destroy */
 	__efivar_entry_iter(efivarfs_destroy, &efivarfs_list, NULL, NULL);
@@ -244,7 +246,7 @@
 static struct file_system_type efivarfs_type = {
 	.owner   = THIS_MODULE,
 	.name    = "efivarfs",
-	.mount   = efivarfs_mount,
+	.init_fs_context = efivarfs_init_fs_context,
 	.kill_sb = efivarfs_kill_sb,
 };