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diff --git a/kernel/drivers/block/zram/zram_drv.h b/kernel/drivers/block/zram/zram_drv.h
new file mode 100644
index 000000000..570c598f4
--- /dev/null
+++ b/kernel/drivers/block/zram/zram_drv.h
@@ -0,0 +1,125 @@
+/*
+ * Compressed RAM block device
+ *
+ * Copyright (C) 2008, 2009, 2010  Nitin Gupta
+ *               2012, 2013 Minchan Kim
+ *
+ * This code is released using a dual license strategy: BSD/GPL
+ * You can choose the licence that better fits your requirements.
+ *
+ * Released under the terms of 3-clause BSD License
+ * Released under the terms of GNU General Public License Version 2.0
+ *
+ */
+
+#ifndef _ZRAM_DRV_H_
+#define _ZRAM_DRV_H_
+
+#include <linux/spinlock.h>
+#include <linux/zsmalloc.h>
+
+#include "zcomp.h"
+
+/*
+ * Some arbitrary value. This is just to catch
+ * invalid value for num_devices module parameter.
+ */
+static const unsigned max_num_devices = 32;
+
+/*-- Configurable parameters */
+
+/*
+ * Pages that compress to size greater than this are stored
+ * uncompressed in memory.
+ */
+static const size_t max_zpage_size = PAGE_SIZE / 4 * 3;
+
+/*
+ * NOTE: max_zpage_size must be less than or equal to:
+ *   ZS_MAX_ALLOC_SIZE. Otherwise, zs_malloc() would
+ * always return failure.
+ */
+
+/*-- End of configurable params */
+
+#define SECTOR_SHIFT		9
+#define SECTORS_PER_PAGE_SHIFT	(PAGE_SHIFT - SECTOR_SHIFT)
+#define SECTORS_PER_PAGE	(1 << SECTORS_PER_PAGE_SHIFT)
+#define ZRAM_LOGICAL_BLOCK_SHIFT 12
+#define ZRAM_LOGICAL_BLOCK_SIZE	(1 << ZRAM_LOGICAL_BLOCK_SHIFT)
+#define ZRAM_SECTOR_PER_LOGICAL_BLOCK	\
+	(1 << (ZRAM_LOGICAL_BLOCK_SHIFT - SECTOR_SHIFT))
+
+
+/*
+ * The lower ZRAM_FLAG_SHIFT bits of table.value is for
+ * object size (excluding header), the higher bits is for
+ * zram_pageflags.
+ *
+ * zram is mainly used for memory efficiency so we want to keep memory
+ * footprint small so we can squeeze size and flags into a field.
+ * The lower ZRAM_FLAG_SHIFT bits is for object size (excluding header),
+ * the higher bits is for zram_pageflags.
+ */
+#define ZRAM_FLAG_SHIFT 24
+
+/* Flags for zram pages (table[page_no].value) */
+enum zram_pageflags {
+	/* Page consists entirely of zeros */
+	ZRAM_ZERO = ZRAM_FLAG_SHIFT,
+	ZRAM_ACCESS,	/* page is now accessed */
+
+	__NR_ZRAM_PAGEFLAGS,
+};
+
+/*-- Data structures */
+
+/* Allocated for each disk page */
+struct zram_table_entry {
+	unsigned long handle;
+	unsigned long value;
+};
+
+struct zram_stats {
+	atomic64_t compr_data_size;	/* compressed size of pages stored */
+	atomic64_t num_reads;	/* failed + successful */
+	atomic64_t num_writes;	/* --do-- */
+	atomic64_t num_migrated;	/* no. of migrated object */
+	atomic64_t failed_reads;	/* can happen when memory is too low */
+	atomic64_t failed_writes;	/* can happen when memory is too low */
+	atomic64_t invalid_io;	/* non-page-aligned I/O requests */
+	atomic64_t notify_free;	/* no. of swap slot free notifications */
+	atomic64_t zero_pages;		/* no. of zero filled pages */
+	atomic64_t pages_stored;	/* no. of pages currently stored */
+	atomic_long_t max_used_pages;	/* no. of maximum pages stored */
+};
+
+struct zram_meta {
+	struct zram_table_entry *table;
+	struct zs_pool *mem_pool;
+};
+
+struct zram {
+	struct zram_meta *meta;
+	struct zcomp *comp;
+	struct gendisk *disk;
+	/* Prevent concurrent execution of device init */
+	struct rw_semaphore init_lock;
+	/*
+	 * the number of pages zram can consume for storing compressed data
+	 */
+	unsigned long limit_pages;
+	int max_comp_streams;
+
+	struct zram_stats stats;
+	atomic_t refcount; /* refcount for zram_meta */
+	/* wait all IO under all of cpu are done */
+	wait_queue_head_t io_done;
+	/*
+	 * This is the limit on amount of *uncompressed* worth of data
+	 * we can store in a disk.
+	 */
+	u64 disksize;	/* bytes */
+	char compressor[10];
+};
+#endif