--- zzzz-none-000/linux-3.10.107/drivers/mtd/mtdblock.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/drivers/mtd/mtdblock.c	2021-02-04 17:41:59.000000000 +0000
@@ -32,6 +32,7 @@
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/blktrans.h>
 #include <linux/mutex.h>
+#include <linux/major.h>
 
 
 struct mtdblk_dev {
@@ -44,8 +45,6 @@
 	enum { STATE_EMPTY, STATE_CLEAN, STATE_DIRTY } cache_state;
 };
 
-static DEFINE_MUTEX(mtdblks_lock);
-
 /*
  * Cache stuff...
  *
@@ -285,10 +284,8 @@
 
 	pr_debug("mtdblock_open\n");
 
-	mutex_lock(&mtdblks_lock);
 	if (mtdblk->count) {
 		mtdblk->count++;
-		mutex_unlock(&mtdblks_lock);
 		return 0;
 	}
 
@@ -301,8 +298,6 @@
 		mtdblk->cache_data = NULL;
 	}
 
-	mutex_unlock(&mtdblks_lock);
-
 	pr_debug("ok\n");
 
 	return 0;
@@ -314,8 +309,6 @@
 
 	pr_debug("mtdblock_release\n");
 
-	mutex_lock(&mtdblks_lock);
-
 	mutex_lock(&mtdblk->cache_mutex);
 	write_cached_data(mtdblk);
 	mutex_unlock(&mtdblk->cache_mutex);
@@ -330,8 +323,6 @@
 		vfree(mtdblk->cache_data);
 	}
 
-	mutex_unlock(&mtdblks_lock);
-
 	pr_debug("ok\n");
 }
 
@@ -373,7 +364,7 @@
 
 static struct mtd_blktrans_ops mtdblock_tr = {
 	.name		= "mtdblock",
-	.major		= 31,
+	.major		= MTD_BLOCK_MAJOR,
 	.part_bits	= 0,
 	.blksize 	= 512,
 	.open		= mtdblock_open,