Merge remote-tracking branch 'origin/v3.10/topic/zram' into linux-linaro-lsk

 Conflicts:
	mm/Kconfig
	mm/Makefile

21 files changed, 1771 insertions, 2238 deletions

diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
index b81ddfea1da0..9da952c9af91 100644
--- a/drivers/block/Kconfig
+++ b/drivers/block/Kconfig
@@ -105,6 +105,8 @@ source "drivers/block/paride/Kconfig"
 
 source "drivers/block/mtip32xx/Kconfig"
 
+source "drivers/block/zram/Kconfig"
+
 config BLK_CPQ_DA
 	tristate "Compaq SMART2 support"
 	depends on PCI && VIRT_TO_BUS
diff --git a/drivers/block/Makefile b/drivers/block/Makefile
index ca07399a8d99..3675937ab651 100644
--- a/drivers/block/Makefile
+++ b/drivers/block/Makefile
@@ -41,6 +41,7 @@ obj-$(CONFIG_BLK_DEV_RBD)     += rbd.o
 obj-$(CONFIG_BLK_DEV_PCIESSD_MTIP32XX)	+= mtip32xx/
 
 obj-$(CONFIG_BLK_DEV_RSXX) += rsxx/
+obj-$(CONFIG_ZRAM) += zram/
 
 nvme-y		:= nvme-core.o nvme-scsi.o
 swim_mod-y	:= swim.o swim_asm.o
diff --git a/drivers/staging/zram/Kconfig b/drivers/block/zram/Kconfig
index 983314c41349..6489c0fd0ea6 100644
--- a/drivers/staging/zram/Kconfig
+++ b/drivers/block/zram/Kconfig
@@ -14,7 +14,16 @@ config ZRAM
 	  disks and maybe many more.
 
 	  See zram.txt for more information.
-	  Project home: <https://compcache.googlecode.com/>
+
+config ZRAM_LZ4_COMPRESS
+	bool "Enable LZ4 algorithm support"
+	depends on ZRAM
+	select LZ4_COMPRESS
+	select LZ4_DECOMPRESS
+	default n
+	help
+	  This option enables LZ4 compression algorithm support. Compression
+	  algorithm can be changed using `comp_algorithm' device attribute.
 
 config ZRAM_DEBUG
 	bool "Compressed RAM block device debug support"
diff --git a/drivers/block/zram/Makefile b/drivers/block/zram/Makefile
new file mode 100644
index 000000000000..be0763ff57a2
--- /dev/null
+++ b/drivers/block/zram/Makefile
@@ -0,0 +1,5 @@
+zram-y	:=	zcomp_lzo.o zcomp.o zram_drv.o
+
+zram-$(CONFIG_ZRAM_LZ4_COMPRESS) += zcomp_lz4.o
+
+obj-$(CONFIG_ZRAM)	+=	zram.o
diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c
new file mode 100644
index 000000000000..f1ff39a3d1c1
--- /dev/null
+++ b/drivers/block/zram/zcomp.c
@@ -0,0 +1,353 @@
+/*
+ * Copyright (C) 2014 Sergey Senozhatsky.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+
+#include "zcomp.h"
+#include "zcomp_lzo.h"
+#ifdef CONFIG_ZRAM_LZ4_COMPRESS
+#include "zcomp_lz4.h"
+#endif
+
+/*
+ * single zcomp_strm backend
+ */
+struct zcomp_strm_single {
+	struct mutex strm_lock;
+	struct zcomp_strm *zstrm;
+};
+
+/*
+ * multi zcomp_strm backend
+ */
+struct zcomp_strm_multi {
+	/* protect strm list */
+	spinlock_t strm_lock;
+	/* max possible number of zstrm streams */
+	int max_strm;
+	/* number of available zstrm streams */
+	int avail_strm;
+	/* list of available strms */
+	struct list_head idle_strm;
+	wait_queue_head_t strm_wait;
+};
+
+static struct zcomp_backend *backends[] = {
+	&zcomp_lzo,
+#ifdef CONFIG_ZRAM_LZ4_COMPRESS
+	&zcomp_lz4,
+#endif
+	NULL
+};
+
+static struct zcomp_backend *find_backend(const char *compress)
+{
+	int i = 0;
+	while (backends[i]) {
+		if (sysfs_streq(compress, backends[i]->name))
+			break;
+		i++;
+	}
+	return backends[i];
+}
+
+static void zcomp_strm_free(struct zcomp *comp, struct zcomp_strm *zstrm)
+{
+	if (zstrm->private)
+		comp->backend->destroy(zstrm->private);
+	free_pages((unsigned long)zstrm->buffer, 1);
+	kfree(zstrm);
+}
+
+/*
+ * allocate new zcomp_strm structure with ->private initialized by
+ * backend, return NULL on error
+ */
+static struct zcomp_strm *zcomp_strm_alloc(struct zcomp *comp)
+{
+	struct zcomp_strm *zstrm = kmalloc(sizeof(*zstrm), GFP_KERNEL);
+	if (!zstrm)
+		return NULL;
+
+	zstrm->private = comp->backend->create();
+	/*
+	 * allocate 2 pages. 1 for compressed data, plus 1 extra for the
+	 * case when compressed size is larger than the original one
+	 */
+	zstrm->buffer = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
+	if (!zstrm->private || !zstrm->buffer) {
+		zcomp_strm_free(comp, zstrm);
+		zstrm = NULL;
+	}
+	return zstrm;
+}
+
+/*
+ * get idle zcomp_strm or wait until other process release
+ * (zcomp_strm_release()) one for us
+ */
+static struct zcomp_strm *zcomp_strm_multi_find(struct zcomp *comp)
+{
+	struct zcomp_strm_multi *zs = comp->stream;
+	struct zcomp_strm *zstrm;
+
+	while (1) {
+		spin_lock(&zs->strm_lock);
+		if (!list_empty(&zs->idle_strm)) {
+			zstrm = list_entry(zs->idle_strm.next,
+					struct zcomp_strm, list);
+			list_del(&zstrm->list);
+			spin_unlock(&zs->strm_lock);
+			return zstrm;
+		}
+		/* zstrm streams limit reached, wait for idle stream */
+		if (zs->avail_strm >= zs->max_strm) {
+			spin_unlock(&zs->strm_lock);
+			wait_event(zs->strm_wait, !list_empty(&zs->idle_strm));
+			continue;
+		}
+		/* allocate new zstrm stream */
+		zs->avail_strm++;
+		spin_unlock(&zs->strm_lock);
+
+		zstrm = zcomp_strm_alloc(comp);
+		if (!zstrm) {
+			spin_lock(&zs->strm_lock);
+			zs->avail_strm--;
+			spin_unlock(&zs->strm_lock);
+			wait_event(zs->strm_wait, !list_empty(&zs->idle_strm));
+			continue;
+		}
+		break;
+	}
+	return zstrm;
+}
+
+/* add stream back to idle list and wake up waiter or free the stream */
+static void zcomp_strm_multi_release(struct zcomp *comp, struct zcomp_strm *zstrm)
+{
+	struct zcomp_strm_multi *zs = comp->stream;
+
+	spin_lock(&zs->strm_lock);
+	if (zs->avail_strm <= zs->max_strm) {
+		list_add(&zstrm->list, &zs->idle_strm);
+		spin_unlock(&zs->strm_lock);
+		wake_up(&zs->strm_wait);
+		return;
+	}
+
+	zs->avail_strm--;
+	spin_unlock(&zs->strm_lock);
+	zcomp_strm_free(comp, zstrm);
+}
+
+/* change max_strm limit */
+static bool zcomp_strm_multi_set_max_streams(struct zcomp *comp, int num_strm)
+{
+	struct zcomp_strm_multi *zs = comp->stream;
+	struct zcomp_strm *zstrm;
+
+	spin_lock(&zs->strm_lock);
+	zs->max_strm = num_strm;
+	/*
+	 * if user has lowered the limit and there are idle streams,
+	 * immediately free as much streams (and memory) as we can.
+	 */
+	while (zs->avail_strm > num_strm && !list_empty(&zs->idle_strm)) {
+		zstrm = list_entry(zs->idle_strm.next,
+				struct zcomp_strm, list);
+		list_del(&zstrm->list);
+		zcomp_strm_free(comp, zstrm);
+		zs->avail_strm--;
+	}
+	spin_unlock(&zs->strm_lock);
+	return true;
+}
+
+static void zcomp_strm_multi_destroy(struct zcomp *comp)
+{
+	struct zcomp_strm_multi *zs = comp->stream;
+	struct zcomp_strm *zstrm;
+
+	while (!list_empty(&zs->idle_strm)) {
+		zstrm = list_entry(zs->idle_strm.next,
+				struct zcomp_strm, list);
+		list_del(&zstrm->list);
+		zcomp_strm_free(comp, zstrm);
+	}
+	kfree(zs);
+}
+
+static int zcomp_strm_multi_create(struct zcomp *comp, int max_strm)
+{
+	struct zcomp_strm *zstrm;
+	struct zcomp_strm_multi *zs;
+
+	comp->destroy = zcomp_strm_multi_destroy;
+	comp->strm_find = zcomp_strm_multi_find;
+	comp->strm_release = zcomp_strm_multi_release;
+	comp->set_max_streams = zcomp_strm_multi_set_max_streams;
+	zs = kmalloc(sizeof(struct zcomp_strm_multi), GFP_KERNEL);
+	if (!zs)
+		return -ENOMEM;
+
+	comp->stream = zs;
+	spin_lock_init(&zs->strm_lock);
+	INIT_LIST_HEAD(&zs->idle_strm);
+	init_waitqueue_head(&zs->strm_wait);
+	zs->max_strm = max_strm;
+	zs->avail_strm = 1;
+
+	zstrm = zcomp_strm_alloc(comp);
+	if (!zstrm) {
+		kfree(zs);
+		return -ENOMEM;
+	}
+	list_add(&zstrm->list, &zs->idle_strm);
+	return 0;
+}
+
+static struct zcomp_strm *zcomp_strm_single_find(struct zcomp *comp)
+{
+	struct zcomp_strm_single *zs = comp->stream;
+	mutex_lock(&zs->strm_lock);
+	return zs->zstrm;
+}
+
+static void zcomp_strm_single_release(struct zcomp *comp,
+		struct zcomp_strm *zstrm)
+{
+	struct zcomp_strm_single *zs = comp->stream;
+	mutex_unlock(&zs->strm_lock);
+}
+
+static bool zcomp_strm_single_set_max_streams(struct zcomp *comp, int num_strm)
+{
+	/* zcomp_strm_single support only max_comp_streams == 1 */
+	return false;
+}
+
+static void zcomp_strm_single_destroy(struct zcomp *comp)
+{
+	struct zcomp_strm_single *zs = comp->stream;
+	zcomp_strm_free(comp, zs->zstrm);
+	kfree(zs);
+}
+
+static int zcomp_strm_single_create(struct zcomp *comp)
+{
+	struct zcomp_strm_single *zs;
+
+	comp->destroy = zcomp_strm_single_destroy;
+	comp->strm_find = zcomp_strm_single_find;
+	comp->strm_release = zcomp_strm_single_release;
+	comp->set_max_streams = zcomp_strm_single_set_max_streams;
+	zs = kmalloc(sizeof(struct zcomp_strm_single), GFP_KERNEL);
+	if (!zs)
+		return -ENOMEM;
+
+	comp->stream = zs;
+	mutex_init(&zs->strm_lock);
+	zs->zstrm = zcomp_strm_alloc(comp);
+	if (!zs->zstrm) {
+		kfree(zs);
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+/* show available compressors */
+ssize_t zcomp_available_show(const char *comp, char *buf)
+{
+	ssize_t sz = 0;
+	int i = 0;
+
+	while (backends[i]) {
+		if (sysfs_streq(comp, backends[i]->name))
+			sz += scnprintf(buf + sz, PAGE_SIZE - sz - 2,
+					"[%s] ", backends[i]->name);
+		else
+			sz += scnprintf(buf + sz, PAGE_SIZE - sz - 2,
+					"%s ", backends[i]->name);
+		i++;
+	}
+	sz += scnprintf(buf + sz, PAGE_SIZE - sz, "\n");
+	return sz;
+}
+
+bool zcomp_set_max_streams(struct zcomp *comp, int num_strm)
+{
+	return comp->set_max_streams(comp, num_strm);
+}
+
+struct zcomp_strm *zcomp_strm_find(struct zcomp *comp)
+{
+	return comp->strm_find(comp);
+}
+
+void zcomp_strm_release(struct zcomp *comp, struct zcomp_strm *zstrm)
+{
+	comp->strm_release(comp, zstrm);
+}
+
+int zcomp_compress(struct zcomp *comp, struct zcomp_strm *zstrm,
+		const unsigned char *src, size_t *dst_len)
+{
+	return comp->backend->compress(src, zstrm->buffer, dst_len,
+			zstrm->private);
+}
+
+int zcomp_decompress(struct zcomp *comp, const unsigned char *src,
+		size_t src_len, unsigned char *dst)
+{
+	return comp->backend->decompress(src, src_len, dst);
+}
+
+void zcomp_destroy(struct zcomp *comp)
+{
+	comp->destroy(comp);
+	kfree(comp);
+}
+
+/*
+ * search available compressors for requested algorithm.
+ * allocate new zcomp and initialize it. return compressing
+ * backend pointer or ERR_PTR if things went bad. ERR_PTR(-EINVAL)
+ * if requested algorithm is not supported, ERR_PTR(-ENOMEM) in
+ * case of allocation error.
+ */
+struct zcomp *zcomp_create(const char *compress, int max_strm)
+{
+	struct zcomp *comp;
+	struct zcomp_backend *backend;
+
+	backend = find_backend(compress);
+	if (!backend)
+		return ERR_PTR(-EINVAL);
+
+	comp = kzalloc(sizeof(struct zcomp), GFP_KERNEL);
+	if (!comp)
+		return ERR_PTR(-ENOMEM);
+
+	comp->backend = backend;
+	if (max_strm > 1)
+		zcomp_strm_multi_create(comp, max_strm);
+	else
+		zcomp_strm_single_create(comp);
+	if (!comp->stream) {
+		kfree(comp);
+		return ERR_PTR(-ENOMEM);
+	}
+	return comp;
+}
diff --git a/drivers/block/zram/zcomp.h b/drivers/block/zram/zcomp.h
new file mode 100644
index 000000000000..c59d1fca72c0
--- /dev/null
+++ b/drivers/block/zram/zcomp.h
@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2014 Sergey Senozhatsky.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _ZCOMP_H_
+#define _ZCOMP_H_
+
+#include <linux/mutex.h>
+
+struct zcomp_strm {
+	/* compression/decompression buffer */
+	void *buffer;
+	/*
+	 * The private data of the compression stream, only compression
+	 * stream backend can touch this (e.g. compression algorithm
+	 * working memory)
+	 */
+	void *private;
+	/* used in multi stream backend, protected by backend strm_lock */
+	struct list_head list;
+};
+
+/* static compression backend */
+struct zcomp_backend {
+	int (*compress)(const unsigned char *src, unsigned char *dst,
+			size_t *dst_len, void *private);
+
+	int (*decompress)(const unsigned char *src, size_t src_len,
+			unsigned char *dst);
+
+	void *(*create)(void);
+	void (*destroy)(void *private);
+
+	const char *name;
+};
+
+/* dynamic per-device compression frontend */
+struct zcomp {
+	void *stream;
+	struct zcomp_backend *backend;
+
+	struct zcomp_strm *(*strm_find)(struct zcomp *comp);
+	void (*strm_release)(struct zcomp *comp, struct zcomp_strm *zstrm);
+	bool (*set_max_streams)(struct zcomp *comp, int num_strm);
+	void (*destroy)(struct zcomp *comp);
+};
+
+ssize_t zcomp_available_show(const char *comp, char *buf);
+
+struct zcomp *zcomp_create(const char *comp, int max_strm);
+void zcomp_destroy(struct zcomp *comp);
+
+struct zcomp_strm *zcomp_strm_find(struct zcomp *comp);
+void zcomp_strm_release(struct zcomp *comp, struct zcomp_strm *zstrm);
+
+int zcomp_compress(struct zcomp *comp, struct zcomp_strm *zstrm,
+		const unsigned char *src, size_t *dst_len);
+
+int zcomp_decompress(struct zcomp *comp, const unsigned char *src,
+		size_t src_len, unsigned char *dst);
+
+bool zcomp_set_max_streams(struct zcomp *comp, int num_strm);
+#endif /* _ZCOMP_H_ */
diff --git a/drivers/block/zram/zcomp_lz4.c b/drivers/block/zram/zcomp_lz4.c
new file mode 100644
index 000000000000..f2afb7e988c3
--- /dev/null
+++ b/drivers/block/zram/zcomp_lz4.c
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2014 Sergey Senozhatsky.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/lz4.h>
+
+#include "zcomp_lz4.h"
+
+static void *zcomp_lz4_create(void)
+{
+	return kzalloc(LZ4_MEM_COMPRESS, GFP_KERNEL);
+}
+
+static void zcomp_lz4_destroy(void *private)
+{
+	kfree(private);
+}
+
+static int zcomp_lz4_compress(const unsigned char *src, unsigned char *dst,
+		size_t *dst_len, void *private)
+{
+	/* return  : Success if return 0 */
+	return lz4_compress(src, PAGE_SIZE, dst, dst_len, private);
+}
+
+static int zcomp_lz4_decompress(const unsigned char *src, size_t src_len,
+		unsigned char *dst)
+{
+	size_t dst_len = PAGE_SIZE;
+	/* return  : Success if return 0 */
+	return lz4_decompress_unknownoutputsize(src, src_len, dst, &dst_len);
+}
+
+struct zcomp_backend zcomp_lz4 = {
+	.compress = zcomp_lz4_compress,
+	.decompress = zcomp_lz4_decompress,
+	.create = zcomp_lz4_create,
+	.destroy = zcomp_lz4_destroy,
+	.name = "lz4",
+};
diff --git a/drivers/block/zram/zcomp_lz4.h b/drivers/block/zram/zcomp_lz4.h
new file mode 100644
index 000000000000..60613fb29dd8
--- /dev/null
+++ b/drivers/block/zram/zcomp_lz4.h
@@ -0,0 +1,17 @@
+/*
+ * Copyright (C) 2014 Sergey Senozhatsky.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _ZCOMP_LZ4_H_
+#define _ZCOMP_LZ4_H_
+
+#include "zcomp.h"
+
+extern struct zcomp_backend zcomp_lz4;
+
+#endif /* _ZCOMP_LZ4_H_ */
diff --git a/drivers/block/zram/zcomp_lzo.c b/drivers/block/zram/zcomp_lzo.c
new file mode 100644
index 000000000000..da1bc47d588e
--- /dev/null
+++ b/drivers/block/zram/zcomp_lzo.c
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2014 Sergey Senozhatsky.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/lzo.h>
+
+#include "zcomp_lzo.h"
+
+static void *lzo_create(void)
+{
+	return kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
+}
+
+static void lzo_destroy(void *private)
+{
+	kfree(private);
+}
+
+static int lzo_compress(const unsigned char *src, unsigned char *dst,
+		size_t *dst_len, void *private)
+{
+	int ret = lzo1x_1_compress(src, PAGE_SIZE, dst, dst_len, private);
+	return ret == LZO_E_OK ? 0 : ret;
+}
+
+static int lzo_decompress(const unsigned char *src, size_t src_len,
+		unsigned char *dst)
+{
+	size_t dst_len = PAGE_SIZE;
+	int ret = lzo1x_decompress_safe(src, src_len, dst, &dst_len);
+	return ret == LZO_E_OK ? 0 : ret;
+}
+
+struct zcomp_backend zcomp_lzo = {
+	.compress = lzo_compress,
+	.decompress = lzo_decompress,
+	.create = lzo_create,
+	.destroy = lzo_destroy,
+	.name = "lzo",
+};
diff --git a/drivers/block/zram/zcomp_lzo.h b/drivers/block/zram/zcomp_lzo.h
new file mode 100644
index 000000000000..128c5807fa14
--- /dev/null
+++ b/drivers/block/zram/zcomp_lzo.h
@@ -0,0 +1,17 @@
+/*
+ * Copyright (C) 2014 Sergey Senozhatsky.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _ZCOMP_LZO_H_
+#define _ZCOMP_LZO_H_
+
+#include "zcomp.h"
+
+extern struct zcomp_backend zcomp_lzo;
+
+#endif /* _ZCOMP_LZO_H_ */
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
new file mode 100644
index 000000000000..45e2e85815ab
--- /dev/null
+++ b/drivers/block/zram/zram_drv.c
@@ -0,0 +1,1162 @@
+/*
+ * 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
+ *
+ */
+
+#define KMSG_COMPONENT "zram"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#ifdef CONFIG_ZRAM_DEBUG
+#define DEBUG
+#endif
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/bio.h>
+#include <linux/bitops.h>
+#include <linux/blkdev.h>
+#include <linux/buffer_head.h>
+#include <linux/device.h>
+#include <linux/genhd.h>
+#include <linux/highmem.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/vmalloc.h>
+#include <linux/err.h>
+
+#include "zram_drv.h"
+
+/* Globals */
+static int zram_major;
+static struct zram *zram_devices;
+static const char *default_compressor = "lzo";
+
+/* Module params (documentation at end) */
+static unsigned int num_devices = 1;
+
+#define ZRAM_ATTR_RO(name)						\
+static ssize_t zram_attr_##name##_show(struct device *d,		\
+				struct device_attribute *attr, char *b)	\
+{									\
+	struct zram *zram = dev_to_zram(d);				\
+	return scnprintf(b, PAGE_SIZE, "%llu\n",			\
+		(u64)atomic64_read(&zram->stats.name));			\
+}									\
+static struct device_attribute dev_attr_##name =			\
+	__ATTR(name, S_IRUGO, zram_attr_##name##_show, NULL);
+
+static inline int init_done(struct zram *zram)
+{
+	return zram->meta != NULL;
+}
+
+static inline struct zram *dev_to_zram(struct device *dev)
+{
+	return (struct zram *)dev_to_disk(dev)->private_data;
+}
+
+static ssize_t disksize_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct zram *zram = dev_to_zram(dev);
+
+	return scnprintf(buf, PAGE_SIZE, "%llu\n", zram->disksize);
+}
+
+static ssize_t initstate_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	u32 val;
+	struct zram *zram = dev_to_zram(dev);
+
+	down_read(&zram->init_lock);
+	val = init_done(zram);
+	up_read(&zram->init_lock);
+
+	return scnprintf(buf, PAGE_SIZE, "%u\n", val);
+}
+
+static ssize_t orig_data_size_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct zram *zram = dev_to_zram(dev);
+
+	return scnprintf(buf, PAGE_SIZE, "%llu\n",
+		(u64)(atomic64_read(&zram->stats.pages_stored)) << PAGE_SHIFT);
+}
+
+static ssize_t mem_used_total_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	u64 val = 0;
+	struct zram *zram = dev_to_zram(dev);
+
+	down_read(&zram->init_lock);
+	if (init_done(zram)) {
+		struct zram_meta *meta = zram->meta;
+		val = zs_get_total_pages(meta->mem_pool);
+	}
+	up_read(&zram->init_lock);
+
+	return scnprintf(buf, PAGE_SIZE, "%llu\n", val << PAGE_SHIFT);
+}
+
+static ssize_t max_comp_streams_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	int val;
+	struct zram *zram = dev_to_zram(dev);
+
+	down_read(&zram->init_lock);
+	val = zram->max_comp_streams;
+	up_read(&zram->init_lock);
+
+	return scnprintf(buf, PAGE_SIZE, "%d\n", val);
+}
+
+static ssize_t mem_limit_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	u64 val;
+	struct zram *zram = dev_to_zram(dev);
+
+	down_read(&zram->init_lock);
+	val = zram->limit_pages;
+	up_read(&zram->init_lock);
+
+	return scnprintf(buf, PAGE_SIZE, "%llu\n", val << PAGE_SHIFT);
+}
+
+static ssize_t mem_limit_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t len)
+{
+	u64 limit;
+	char *tmp;
+	struct zram *zram = dev_to_zram(dev);
+
+	limit = memparse(buf, &tmp);
+	if (buf == tmp) /* no chars parsed, invalid input */
+		return -EINVAL;
+
+	down_write(&zram->init_lock);
+	zram->limit_pages = PAGE_ALIGN(limit) >> PAGE_SHIFT;
+	up_write(&zram->init_lock);
+
+	return len;
+}
+
+static ssize_t mem_used_max_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	u64 val = 0;
+	struct zram *zram = dev_to_zram(dev);
+
+	down_read(&zram->init_lock);
+	if (init_done(zram))
+		val = atomic_long_read(&zram->stats.max_used_pages);
+	up_read(&zram->init_lock);
+
+	return scnprintf(buf, PAGE_SIZE, "%llu\n", val << PAGE_SHIFT);
+}
+
+static ssize_t mem_used_max_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t len)
+{
+	int err;
+	unsigned long val;
+	struct zram *zram = dev_to_zram(dev);
+
+	err = kstrtoul(buf, 10, &val);
+	if (err || val != 0)
+		return -EINVAL;
+
+	down_read(&zram->init_lock);
+	if (init_done(zram)) {
+		struct zram_meta *meta = zram->meta;
+		atomic_long_set(&zram->stats.max_used_pages,
+				zs_get_total_pages(meta->mem_pool));
+	}
+	up_read(&zram->init_lock);
+
+	return len;
+}
+
+static ssize_t max_comp_streams_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t len)
+{
+	int num;
+	struct zram *zram = dev_to_zram(dev);
+	int ret;
+
+	ret = kstrtoint(buf, 0, &num);
+	if (ret < 0)
+		return ret;
+	if (num < 1)
+		return -EINVAL;
+
+	down_write(&zram->init_lock);
+	if (init_done(zram)) {
+		if (!zcomp_set_max_streams(zram->comp, num)) {
+			pr_info("Cannot change max compression streams\n");
+			ret = -EINVAL;
+			goto out;
+		}
+	}
+
+	zram->max_comp_streams = num;
+	ret = len;
+out:
+	up_write(&zram->init_lock);
+	return ret;
+}
+
+static ssize_t comp_algorithm_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	size_t sz;
+	struct zram *zram = dev_to_zram(dev);
+
+	down_read(&zram->init_lock);
+	sz = zcomp_available_show(zram->compressor, buf);
+	up_read(&zram->init_lock);
+
+	return sz;
+}
+
+static ssize_t comp_algorithm_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t len)
+{
+	struct zram *zram = dev_to_zram(dev);
+	down_write(&zram->init_lock);
+	if (init_done(zram)) {
+		up_write(&zram->init_lock);
+		pr_info("Can't change algorithm for initialized device\n");
+		return -EBUSY;
+	}
+	strlcpy(zram->compressor, buf, sizeof(zram->compressor));
+	up_write(&zram->init_lock);
+	return len;
+}
+
+/* flag operations needs meta->tb_lock */
+static int zram_test_flag(struct zram_meta *meta, u32 index,
+			enum zram_pageflags flag)
+{
+	return meta->table[index].value & BIT(flag);
+}
+
+static void zram_set_flag(struct zram_meta *meta, u32 index,
+			enum zram_pageflags flag)
+{
+	meta->table[index].value |= BIT(flag);
+}
+
+static void zram_clear_flag(struct zram_meta *meta, u32 index,
+			enum zram_pageflags flag)
+{
+	meta->table[index].value &= ~BIT(flag);
+}
+
+static size_t zram_get_obj_size(struct zram_meta *meta, u32 index)
+{
+	return meta->table[index].value & (BIT(ZRAM_FLAG_SHIFT) - 1);
+}
+
+static void zram_set_obj_size(struct zram_meta *meta,
+					u32 index, size_t size)
+{
+	unsigned long flags = meta->table[index].value >> ZRAM_FLAG_SHIFT;
+
+	meta->table[index].value = (flags << ZRAM_FLAG_SHIFT) | size;
+}
+
+static inline int is_partial_io(struct bio_vec *bvec)
+{
+	return bvec->bv_len != PAGE_SIZE;
+}
+
+/*
+ * Check if request is within bounds and aligned on zram logical blocks.
+ */
+static inline int valid_io_request(struct zram *zram, struct bio *bio)
+{
+	u64 start, end, bound;
+
+	/* unaligned request */
+	if (unlikely(bio->bi_sector & (ZRAM_SECTOR_PER_LOGICAL_BLOCK - 1)))
+		return 0;
+	if (unlikely(bio->bi_size & (ZRAM_LOGICAL_BLOCK_SIZE - 1)))
+		return 0;
+
+	start = bio->bi_sector;
+	end = start + (bio->bi_size >> SECTOR_SHIFT);
+	bound = zram->disksize >> SECTOR_SHIFT;
+	/* out of range range */
+	if (unlikely(start >= bound || end >= bound || start > end))
+		return 0;
+
+	/* I/O request is valid */
+	return 1;
+}
+
+static void zram_meta_free(struct zram_meta *meta, u64 disksize)
+{
+	size_t num_pages = disksize >> PAGE_SHIFT;
+	size_t index;
+
+	/* Free all pages that are still in this zram device */
+	for (index = 0; index < num_pages; index++) {
+		unsigned long handle = meta->table[index].handle;
+
+		if (!handle)
+			continue;
+
+		zs_free(meta->mem_pool, handle);
+	}
+
+	zs_destroy_pool(meta->mem_pool);
+	vfree(meta->table);
+	kfree(meta);
+}
+
+static struct zram_meta *zram_meta_alloc(u64 disksize)
+{
+	size_t num_pages;
+	struct zram_meta *meta = kmalloc(sizeof(*meta), GFP_KERNEL);
+	if (!meta)
+		goto out;
+
+	num_pages = disksize >> PAGE_SHIFT;
+	meta->table = vzalloc(num_pages * sizeof(*meta->table));
+	if (!meta->table) {
+		pr_err("Error allocating zram address table\n");
+		goto free_meta;
+	}
+
+	meta->mem_pool = zs_create_pool(GFP_NOIO | __GFP_HIGHMEM);
+	if (!meta->mem_pool) {
+		pr_err("Error creating memory pool\n");
+		goto free_table;
+	}
+
+	return meta;
+
+free_table:
+	vfree(meta->table);
+free_meta:
+	kfree(meta);
+	meta = NULL;
+out:
+	return meta;
+}
+
+static void update_position(u32 *index, int *offset, struct bio_vec *bvec)
+{
+	if (*offset + bvec->bv_len >= PAGE_SIZE)
+		(*index)++;
+	*offset = (*offset + bvec->bv_len) % PAGE_SIZE;
+}
+
+static int page_zero_filled(void *ptr)
+{
+	unsigned int pos;
+	unsigned long *page;
+
+	page = (unsigned long *)ptr;
+
+	for (pos = 0; pos != PAGE_SIZE / sizeof(*page); pos++) {
+		if (page[pos])
+			return 0;
+	}
+
+	return 1;
+}
+
+static void handle_zero_page(struct bio_vec *bvec)
+{
+	struct page *page = bvec->bv_page;
+	void *user_mem;
+
+	user_mem = kmap_atomic(page);
+	if (is_partial_io(bvec))
+		memset(user_mem + bvec->bv_offset, 0, bvec->bv_len);
+	else
+		clear_page(user_mem);
+	kunmap_atomic(user_mem);
+
+	flush_dcache_page(page);
+}
+
+
+/*
+ * To protect concurrent access to the same index entry,
+ * caller should hold this table index entry's bit_spinlock to
+ * indicate this index entry is accessing.
+ */
+static void zram_free_page(struct zram *zram, size_t index)
+{
+	struct zram_meta *meta = zram->meta;
+	unsigned long handle = meta->table[index].handle;
+
+	if (unlikely(!handle)) {
+		/*
+		 * No memory is allocated for zero filled pages.
+		 * Simply clear zero page flag.
+		 */
+		if (zram_test_flag(meta, index, ZRAM_ZERO)) {
+			zram_clear_flag(meta, index, ZRAM_ZERO);
+			atomic64_dec(&zram->stats.zero_pages);
+		}
+		return;
+	}
+
+	zs_free(meta->mem_pool, handle);
+
+	atomic64_sub(zram_get_obj_size(meta, index),
+			&zram->stats.compr_data_size);
+	atomic64_dec(&zram->stats.pages_stored);
+
+	meta->table[index].handle = 0;
+	zram_set_obj_size(meta, index, 0);
+}
+
+static int zram_decompress_page(struct zram *zram, char *mem, u32 index)
+{
+	int ret = 0;
+	unsigned char *cmem;
+	struct zram_meta *meta = zram->meta;
+	unsigned long handle;
+	size_t size;
+
+	bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
+	handle = meta->table[index].handle;
+	size = zram_get_obj_size(meta, index);
+
+	if (!handle || zram_test_flag(meta, index, ZRAM_ZERO)) {
+		bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+		clear_page(mem);
+		return 0;
+	}
+
+	cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_RO);
+	if (size == PAGE_SIZE)
+		copy_page(mem, cmem);
+	else
+		ret = zcomp_decompress(zram->comp, cmem, size, mem);
+	zs_unmap_object(meta->mem_pool, handle);
+	bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+
+	/* Should NEVER happen. Return bio error if it does. */
+	if (unlikely(ret)) {
+		pr_err("Decompression failed! err=%d, page=%u\n", ret, index);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
+			  u32 index, int offset, struct bio *bio)
+{
+	int ret;
+	struct page *page;
+	unsigned char *user_mem, *uncmem = NULL;
+	struct zram_meta *meta = zram->meta;
+	page = bvec->bv_page;
+
+	bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
+	if (unlikely(!meta->table[index].handle) ||
+			zram_test_flag(meta, index, ZRAM_ZERO)) {
+		bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+		handle_zero_page(bvec);
+		return 0;
+	}
+	bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+
+	if (is_partial_io(bvec))
+		/* Use  a temporary buffer to decompress the page */
+		uncmem = kmalloc(PAGE_SIZE, GFP_NOIO);
+
+	user_mem = kmap_atomic(page);
+	if (!is_partial_io(bvec))
+		uncmem = user_mem;
+
+	if (!uncmem) {
+		pr_info("Unable to allocate temp memory\n");
+		ret = -ENOMEM;
+		goto out_cleanup;
+	}
+
+	ret = zram_decompress_page(zram, uncmem, index);
+	/* Should NEVER happen. Return bio error if it does. */
+	if (unlikely(ret))
+		goto out_cleanup;
+
+	if (is_partial_io(bvec))
+		memcpy(user_mem + bvec->bv_offset, uncmem + offset,
+				bvec->bv_len);
+
+	flush_dcache_page(page);
+	ret = 0;
+out_cleanup:
+	kunmap_atomic(user_mem);
+	if (is_partial_io(bvec))
+		kfree(uncmem);
+	return ret;
+}
+
+static inline void update_used_max(struct zram *zram,
+					const unsigned long pages)
+{
+	int old_max, cur_max;
+
+	old_max = atomic_long_read(&zram->stats.max_used_pages);
+
+	do {
+		cur_max = old_max;
+		if (pages > cur_max)
+			old_max = atomic_long_cmpxchg(
+				&zram->stats.max_used_pages, cur_max, pages);
+	} while (old_max != cur_max);
+}
+
+static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
+			   int offset)
+{
+	int ret = 0;
+	size_t clen;
+	unsigned long handle;
+	struct page *page;
+	unsigned char *user_mem, *cmem, *src, *uncmem = NULL;
+	struct zram_meta *meta = zram->meta;
+	struct zcomp_strm *zstrm;
+	bool locked = false;
+	unsigned long alloced_pages;
+
+	page = bvec->bv_page;
+	if (is_partial_io(bvec)) {
+		/*
+		 * This is a partial IO. We need to read the full page
+		 * before to write the changes.
+		 */
+		uncmem = kmalloc(PAGE_SIZE, GFP_NOIO);
+		if (!uncmem) {
+			ret = -ENOMEM;
+			goto out;
+		}
+		ret = zram_decompress_page(zram, uncmem, index);
+		if (ret)
+			goto out;
+	}
+
+	zstrm = zcomp_strm_find(zram->comp);
+	locked = true;
+	user_mem = kmap_atomic(page);
+
+	if (is_partial_io(bvec)) {
+		memcpy(uncmem + offset, user_mem + bvec->bv_offset,
+		       bvec->bv_len);
+		kunmap_atomic(user_mem);
+		user_mem = NULL;
+	} else {
+		uncmem = user_mem;
+	}
+
+	if (page_zero_filled(uncmem)) {
+		if (user_mem)
+			kunmap_atomic(user_mem);
+		/* Free memory associated with this sector now. */
+		bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
+		zram_free_page(zram, index);
+		zram_set_flag(meta, index, ZRAM_ZERO);
+		bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+
+		atomic64_inc(&zram->stats.zero_pages);
+		ret = 0;
+		goto out;
+	}
+
+	ret = zcomp_compress(zram->comp, zstrm, uncmem, &clen);
+	if (!is_partial_io(bvec)) {
+		kunmap_atomic(user_mem);
+		user_mem = NULL;
+		uncmem = NULL;
+	}
+
+	if (unlikely(ret)) {
+		pr_err("Compression failed! err=%d\n", ret);
+		goto out;
+	}
+	src = zstrm->buffer;
+	if (unlikely(clen > max_zpage_size)) {
+		clen = PAGE_SIZE;
+		if (is_partial_io(bvec))
+			src = uncmem;
+	}
+
+	handle = zs_malloc(meta->mem_pool, clen);
+	if (!handle) {
+		pr_info("Error allocating memory for compressed page: %u, size=%zu\n",
+			index, clen);
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	alloced_pages = zs_get_total_pages(meta->mem_pool);
+	if (zram->limit_pages && alloced_pages > zram->limit_pages) {
+		zs_free(meta->mem_pool, handle);
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	update_used_max(zram, alloced_pages);
+
+	cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_WO);
+
+	if ((clen == PAGE_SIZE) && !is_partial_io(bvec)) {
+		src = kmap_atomic(page);
+		copy_page(cmem, src);
+		kunmap_atomic(src);
+	} else {
+		memcpy(cmem, src, clen);
+	}
+
+	zcomp_strm_release(zram->comp, zstrm);
+	locked = false;
+	zs_unmap_object(meta->mem_pool, handle);
+
+	/*
+	 * Free memory associated with this sector
+	 * before overwriting unused sectors.
+	 */
+	bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
+	zram_free_page(zram, index);
+
+	meta->table[index].handle = handle;
+	zram_set_obj_size(meta, index, clen);
+	bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+
+	/* Update stats */
+	atomic64_add(clen, &zram->stats.compr_data_size);
+	atomic64_inc(&zram->stats.pages_stored);
+out:
+	if (locked)
+		zcomp_strm_release(zram->comp, zstrm);
+	if (is_partial_io(bvec))
+		kfree(uncmem);
+	return ret;
+}
+
+static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index,
+			int offset, struct bio *bio)
+{
+	int ret;
+	int rw = bio_data_dir(bio);
+
+	if (rw == READ) {
+		atomic64_inc(&zram->stats.num_reads);
+		ret = zram_bvec_read(zram, bvec, index, offset, bio);
+	} else {
+		atomic64_inc(&zram->stats.num_writes);
+		ret = zram_bvec_write(zram, bvec, index, offset);
+	}
+
+	if (unlikely(ret)) {
+		if (rw == READ)
+			atomic64_inc(&zram->stats.failed_reads);
+		else
+			atomic64_inc(&zram->stats.failed_writes);
+	}
+
+	return ret;
+}
+
+/*
+ * zram_bio_discard - handler on discard request
+ * @index: physical block index in PAGE_SIZE units
+ * @offset: byte offset within physical block
+ */
+static void zram_bio_discard(struct zram *zram, u32 index,
+			     int offset, struct bio *bio)
+{
+	size_t n = bio->bi_size;
+	struct zram_meta *meta = zram->meta;
+
+	/*
+	 * zram manages data in physical block size units. Because logical block
+	 * size isn't identical with physical block size on some arch, we
+	 * could get a discard request pointing to a specific offset within a
+	 * certain physical block.  Although we can handle this request by
+	 * reading that physiclal block and decompressing and partially zeroing
+	 * and re-compressing and then re-storing it, this isn't reasonable
+	 * because our intent with a discard request is to save memory.  So
+	 * skipping this logical block is appropriate here.
+	 */
+	if (offset) {
+		if (n <= (PAGE_SIZE - offset))
+			return;
+
+		n -= (PAGE_SIZE - offset);
+		index++;
+	}
+
+	while (n >= PAGE_SIZE) {
+		bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
+		zram_free_page(zram, index);
+		bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+		atomic64_inc(&zram->stats.notify_free);
+		index++;
+		n -= PAGE_SIZE;
+	}
+}
+
+static void zram_reset_device(struct zram *zram)
+{
+	down_write(&zram->init_lock);
+
+	zram->limit_pages = 0;
+
+	if (!init_done(zram)) {
+		up_write(&zram->init_lock);
+		return;
+	}
+
+	zcomp_destroy(zram->comp);
+	zram->max_comp_streams = 1;
+	zram_meta_free(zram->meta, zram->disksize);
+	zram->meta = NULL;
+	/* Reset stats */
+	memset(&zram->stats, 0, sizeof(zram->stats));
+
+	zram->disksize = 0;
+	up_write(&zram->init_lock);
+}
+
+static ssize_t disksize_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t len)
+{
+	u64 disksize;
+	struct zcomp *comp;
+	struct zram_meta *meta;
+	struct zram *zram = dev_to_zram(dev);
+	int err;
+
+	disksize = memparse(buf, NULL);
+	if (!disksize)
+		return -EINVAL;
+
+	disksize = PAGE_ALIGN(disksize);
+	meta = zram_meta_alloc(disksize);
+	if (!meta)
+		return -ENOMEM;
+
+	comp = zcomp_create(zram->compressor, zram->max_comp_streams);
+	if (IS_ERR(comp)) {
+		pr_info("Cannot initialise %s compressing backend\n",
+				zram->compressor);
+		err = PTR_ERR(comp);
+		goto out_free_meta;
+	}
+
+	down_write(&zram->init_lock);
+	if (init_done(zram)) {
+		pr_info("Cannot change disksize for initialized device\n");
+		err = -EBUSY;
+		goto out_destroy_comp;
+	}
+
+	zram->meta = meta;
+	zram->comp = comp;
+	zram->disksize = disksize;
+	set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
+	up_write(&zram->init_lock);
+
+	/*
+	 * Revalidate disk out of the init_lock to avoid lockdep splat.
+	 * It's okay because disk's capacity is protected by init_lock
+	 * so that revalidate_disk always sees up-to-date capacity.
+	 */
+	revalidate_disk(zram->disk);
+
+	return len;
+
+out_destroy_comp:
+	up_write(&zram->init_lock);
+	zcomp_destroy(comp);
+out_free_meta:
+	zram_meta_free(meta, disksize);
+	return err;
+}
+
+static ssize_t reset_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t len)
+{
+	int ret;
+	unsigned short do_reset;
+	struct zram *zram;
+	struct block_device *bdev;
+
+	zram = dev_to_zram(dev);
+	bdev = bdget_disk(zram->disk, 0);
+
+	if (!bdev)
+		return -ENOMEM;
+
+	mutex_lock(&bdev->bd_mutex);
+	/* Do not reset an active device! */
+	if (bdev->bd_holders) {
+		ret = -EBUSY;
+		goto out;
+	}
+
+	ret = kstrtou16(buf, 10, &do_reset);
+	if (ret)
+		goto out;
+
+	if (!do_reset) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* Make sure all pending I/O is finished */
+	fsync_bdev(bdev);
+	zram_reset_device(zram);
+	set_capacity(zram->disk, 0);
+
+	mutex_unlock(&bdev->bd_mutex);
+	revalidate_disk(zram->disk);
+	bdput(bdev);
+
+	return len;
+
+out:
+	mutex_unlock(&bdev->bd_mutex);
+	bdput(bdev);
+	return ret;
+}
+
+static void __zram_make_request(struct zram *zram, struct bio *bio)
+{
+	int i, offset;
+	u32 index;
+	struct bio_vec *bvec;
+
+
+	index = bio->bi_sector >> SECTORS_PER_PAGE_SHIFT;
+	offset = (bio->bi_sector & (SECTORS_PER_PAGE - 1)) << SECTOR_SHIFT;
+
+	if (unlikely(bio->bi_rw & REQ_DISCARD)) {
+		zram_bio_discard(zram, index, offset, bio);
+		bio_endio(bio, 0);
+		return;
+	}
+
+	bio_for_each_segment(bvec, bio, i) {
+		int max_transfer_size = PAGE_SIZE - offset;
+
+		if (bvec->bv_len > max_transfer_size) {
+			/*
+			 * zram_bvec_rw() can only make operation on a single
+			 * zram page. Split the bio vector.
+			 */
+			struct bio_vec bv;
+
+			bv.bv_page = bvec->bv_page;
+			bv.bv_len = max_transfer_size;
+			bv.bv_offset = bvec->bv_offset;
+
+			if (zram_bvec_rw(zram, &bv, index, offset, bio) < 0)
+				goto out;
+
+			bv.bv_len = bvec->bv_len - max_transfer_size;
+			bv.bv_offset += max_transfer_size;
+			if (zram_bvec_rw(zram, &bv, index + 1, 0, bio) < 0)
+				goto out;
+		} else
+			if (zram_bvec_rw(zram, bvec, index, offset, bio) < 0)
+				goto out;
+
+		update_position(&index, &offset, bvec);
+	}
+
+	set_bit(BIO_UPTODATE, &bio->bi_flags);
+	bio_endio(bio, 0);
+	return;
+
+out:
+	bio_io_error(bio);
+}
+
+/*
+ * Handler function for all zram I/O requests.
+ */
+static void zram_make_request(struct request_queue *queue, struct bio *bio)
+{
+	struct zram *zram = queue->queuedata;
+
+	down_read(&zram->init_lock);
+	if (unlikely(!init_done(zram)))
+		goto error;
+
+	if (!valid_io_request(zram, bio)) {
+		atomic64_inc(&zram->stats.invalid_io);
+		goto error;
+	}
+
+	__zram_make_request(zram, bio);
+	up_read(&zram->init_lock);
+
+	return;
+
+error:
+	up_read(&zram->init_lock);
+	bio_io_error(bio);
+}
+
+static void zram_slot_free_notify(struct block_device *bdev,
+				unsigned long index)
+{
+	struct zram *zram;
+	struct zram_meta *meta;
+
+	zram = bdev->bd_disk->private_data;
+	meta = zram->meta;
+
+	bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
+	zram_free_page(zram, index);
+	bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+	atomic64_inc(&zram->stats.notify_free);
+}
+
+static const struct block_device_operations zram_devops = {
+	.swap_slot_free_notify = zram_slot_free_notify,
+	.owner = THIS_MODULE
+};
+
+static DEVICE_ATTR(disksize, S_IRUGO | S_IWUSR,
+		disksize_show, disksize_store);
+static DEVICE_ATTR(initstate, S_IRUGO, initstate_show, NULL);
+static DEVICE_ATTR(reset, S_IWUSR, NULL, reset_store);
+static DEVICE_ATTR(orig_data_size, S_IRUGO, orig_data_size_show, NULL);
+static DEVICE_ATTR(mem_used_total, S_IRUGO, mem_used_total_show, NULL);
+static DEVICE_ATTR(mem_limit, S_IRUGO | S_IWUSR, mem_limit_show,
+		mem_limit_store);
+static DEVICE_ATTR(mem_used_max, S_IRUGO | S_IWUSR, mem_used_max_show,
+		mem_used_max_store);
+static DEVICE_ATTR(max_comp_streams, S_IRUGO | S_IWUSR,
+		max_comp_streams_show, max_comp_streams_store);
+static DEVICE_ATTR(comp_algorithm, S_IRUGO | S_IWUSR,
+		comp_algorithm_show, comp_algorithm_store);
+
+ZRAM_ATTR_RO(num_reads);
+ZRAM_ATTR_RO(num_writes);
+ZRAM_ATTR_RO(failed_reads);
+ZRAM_ATTR_RO(failed_writes);
+ZRAM_ATTR_RO(invalid_io);
+ZRAM_ATTR_RO(notify_free);
+ZRAM_ATTR_RO(zero_pages);
+ZRAM_ATTR_RO(compr_data_size);
+
+static struct attribute *zram_disk_attrs[] = {
+	&dev_attr_disksize.attr,
+	&dev_attr_initstate.attr,
+	&dev_attr_reset.attr,
+	&dev_attr_num_reads.attr,
+	&dev_attr_num_writes.attr,
+	&dev_attr_failed_reads.attr,
+	&dev_attr_failed_writes.attr,
+	&dev_attr_invalid_io.attr,
+	&dev_attr_notify_free.attr,
+	&dev_attr_zero_pages.attr,
+	&dev_attr_orig_data_size.attr,
+	&dev_attr_compr_data_size.attr,
+	&dev_attr_mem_used_total.attr,
+	&dev_attr_mem_limit.attr,
+	&dev_attr_mem_used_max.attr,
+	&dev_attr_max_comp_streams.attr,
+	&dev_attr_comp_algorithm.attr,
+	NULL,
+};
+
+static struct attribute_group zram_disk_attr_group = {
+	.attrs = zram_disk_attrs,
+};
+
+static int create_device(struct zram *zram, int device_id)
+{
+	int ret = -ENOMEM;
+
+	init_rwsem(&zram->init_lock);
+
+	zram->queue = blk_alloc_queue(GFP_KERNEL);
+	if (!zram->queue) {
+		pr_err("Error allocating disk queue for device %d\n",
+			device_id);
+		goto out;
+	}
+
+	blk_queue_make_request(zram->queue, zram_make_request);
+	zram->queue->queuedata = zram;
+
+	 /* gendisk structure */
+	zram->disk = alloc_disk(1);
+	if (!zram->disk) {
+		pr_warn("Error allocating disk structure for device %d\n",
+			device_id);
+		goto out_free_queue;
+	}
+
+	zram->disk->major = zram_major;
+	zram->disk->first_minor = device_id;
+	zram->disk->fops = &zram_devops;
+	zram->disk->queue = zram->queue;
+	zram->disk->private_data = zram;
+	snprintf(zram->disk->disk_name, 16, "zram%d", device_id);
+
+	/* Actual capacity set using syfs (/sys/block/zram<id>/disksize */
+	set_capacity(zram->disk, 0);
+	/* zram devices sort of resembles non-rotational disks */
+	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue);
+	/*
+	 * To ensure that we always get PAGE_SIZE aligned
+	 * and n*PAGE_SIZED sized I/O requests.
+	 */
+	blk_queue_physical_block_size(zram->disk->queue, PAGE_SIZE);
+	blk_queue_logical_block_size(zram->disk->queue,
+					ZRAM_LOGICAL_BLOCK_SIZE);
+	blk_queue_io_min(zram->disk->queue, PAGE_SIZE);
+	blk_queue_io_opt(zram->disk->queue, PAGE_SIZE);
+	zram->disk->queue->limits.discard_granularity = PAGE_SIZE;
+	zram->disk->queue->limits.max_discard_sectors = UINT_MAX;
+	/*
+	 * zram_bio_discard() will clear all logical blocks if logical block
+	 * size is identical with physical block size(PAGE_SIZE). But if it is
+	 * different, we will skip discarding some parts of logical blocks in
+	 * the part of the request range which isn't aligned to physical block
+	 * size.  So we can't ensure that all discarded logical blocks are
+	 * zeroed.
+	 */
+	if (ZRAM_LOGICAL_BLOCK_SIZE == PAGE_SIZE)
+		zram->disk->queue->limits.discard_zeroes_data = 1;
+	else
+		zram->disk->queue->limits.discard_zeroes_data = 0;
+	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, zram->disk->queue);
+
+	add_disk(zram->disk);
+
+	ret = sysfs_create_group(&disk_to_dev(zram->disk)->kobj,
+				&zram_disk_attr_group);
+	if (ret < 0) {
+		pr_warn("Error creating sysfs group");
+		goto out_free_disk;
+	}
+	strlcpy(zram->compressor, default_compressor, sizeof(zram->compressor));
+	zram->meta = NULL;
+	zram->max_comp_streams = 1;
+	return 0;
+
+out_free_disk:
+	del_gendisk(zram->disk);
+	put_disk(zram->disk);
+out_free_queue:
+	blk_cleanup_queue(zram->queue);
+out:
+	return ret;
+}
+
+static void destroy_device(struct zram *zram)
+{
+	sysfs_remove_group(&disk_to_dev(zram->disk)->kobj,
+			&zram_disk_attr_group);
+
+	del_gendisk(zram->disk);
+	put_disk(zram->disk);
+
+	blk_cleanup_queue(zram->queue);
+}
+
+static int __init zram_init(void)
+{
+	int ret, dev_id;
+
+	if (num_devices > max_num_devices) {
+		pr_warn("Invalid value for num_devices: %u\n",
+				num_devices);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	zram_major = register_blkdev(0, "zram");
+	if (zram_major <= 0) {
+		pr_warn("Unable to get major number\n");
+		ret = -EBUSY;
+		goto out;
+	}
+
+	/* Allocate the device array and initialize each one */
+	zram_devices = kzalloc(num_devices * sizeof(struct zram), GFP_KERNEL);
+	if (!zram_devices) {
+		ret = -ENOMEM;
+		goto unregister;
+	}
+
+	for (dev_id = 0; dev_id < num_devices; dev_id++) {
+		ret = create_device(&zram_devices[dev_id], dev_id);
+		if (ret)
+			goto free_devices;
+	}
+
+	pr_info("Created %u device(s) ...\n", num_devices);
+
+	return 0;
+
+free_devices:
+	while (dev_id)
+		destroy_device(&zram_devices[--dev_id]);
+	kfree(zram_devices);
+unregister:
+	unregister_blkdev(zram_major, "zram");
+out:
+	return ret;
+}
+
+static void __exit zram_exit(void)
+{
+	int i;
+	struct zram *zram;
+
+	for (i = 0; i < num_devices; i++) {
+		zram = &zram_devices[i];
+
+		destroy_device(zram);
+		/*
+		 * Shouldn't access zram->disk after destroy_device
+		 * because destroy_device already released zram->disk.
+		 */
+		zram_reset_device(zram);
+	}
+
+	unregister_blkdev(zram_major, "zram");
+
+	kfree(zram_devices);
+	pr_debug("Cleanup done!\n");
+}
+
+module_init(zram_init);
+module_exit(zram_exit);
+
+module_param(num_devices, uint, 0);
+MODULE_PARM_DESC(num_devices, "Number of zram devices");
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Nitin Gupta <ngupta@vflare.org>");
+MODULE_DESCRIPTION("Compressed RAM Block Device");
diff --git a/drivers/staging/zram/zram_drv.h b/drivers/block/zram/zram_drv.h
index d542eee81357..b05a816b09ac 100644
--- a/drivers/staging/zram/zram_drv.h
+++ b/drivers/block/zram/zram_drv.h
@@ -2,6 +2,7 @@
  * 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.
@@ -9,16 +10,15 @@
  * Released under the terms of 3-clause BSD License
  * Released under the terms of GNU General Public License Version 2.0
  *
- * Project home: http://compcache.googlecode.com
  */
 
 #ifndef _ZRAM_DRV_H_
 #define _ZRAM_DRV_H_
 
 #include <linux/spinlock.h>
-#include <linux/mutex.h>
+#include <linux/zsmalloc.h>
 
-#include "../zsmalloc/zsmalloc.h"
+#include "zcomp.h"
 
 /*
  * Some arbitrary value. This is just to catch
@@ -43,7 +43,6 @@ static const size_t max_zpage_size = PAGE_SIZE / 4 * 3;
 /*-- End of configurable params */
 
 #define SECTOR_SHIFT		9
-#define SECTOR_SIZE		(1 << SECTOR_SHIFT)
 #define SECTORS_PER_PAGE_SHIFT	(PAGE_SHIFT - SECTOR_SHIFT)
 #define SECTORS_PER_PAGE	(1 << SECTORS_PER_PAGE_SHIFT)
 #define ZRAM_LOGICAL_BLOCK_SHIFT 12
@@ -51,10 +50,24 @@ static const size_t max_zpage_size = PAGE_SIZE / 4 * 3;
 #define ZRAM_SECTOR_PER_LOGICAL_BLOCK	\
 	(1 << (ZRAM_LOGICAL_BLOCK_SHIFT - SECTOR_SHIFT))
 
-/* Flags for zram pages (table[page_no].flags) */
+
+/*
+ * 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_ZERO = ZRAM_FLAG_SHIFT,
+	ZRAM_ACCESS,	/* page is now accessed */
 
 	__NR_ZRAM_PAGEFLAGS,
 };
@@ -62,43 +75,35 @@ enum zram_pageflags {
 /*-- Data structures */
 
 /* Allocated for each disk page */
-struct table {
+struct zram_table_entry {
 	unsigned long handle;
-	u16 size;	/* object size (excluding header) */
-	u8 count;	/* object ref count (not yet used) */
-	u8 flags;
-} __aligned(4);
+	unsigned long value;
+};
 
 struct zram_stats {
-	u64 compr_size;		/* compressed size of pages stored */
-	u64 num_reads;		/* failed + successful */
-	u64 num_writes;		/* --do-- */
-	u64 failed_reads;	/* should NEVER! happen */
-	u64 failed_writes;	/* can happen when memory is too low */
-	u64 invalid_io;		/* non-page-aligned I/O requests */
-	u64 notify_free;	/* no. of swap slot free notifications */
-	u32 pages_zero;		/* no. of zero filled pages */
-	u32 pages_stored;	/* no. of pages currently stored */
-	u32 good_compress;	/* % of pages with compression ratio<=50% */
-	u32 bad_compress;	/* % of pages with compression ratio>=75% */
+	atomic64_t compr_data_size;	/* compressed size of pages stored */
+	atomic64_t num_reads;	/* failed + successful */
+	atomic64_t num_writes;	/* --do-- */
+	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 {
-	void *compress_workmem;
-	void *compress_buffer;
-	struct table *table;
+	struct zram_table_entry *table;
 	struct zs_pool *mem_pool;
 };
 
 struct zram {
 	struct zram_meta *meta;
-	spinlock_t stat64_lock;	/* protect 64-bit stats */
-	struct rw_semaphore lock; /* protect compression buffers, table,
-				   * 32bit stat counters against concurrent
-				   * notifications, reads and writes */
 	struct request_queue *queue;
 	struct gendisk *disk;
-	int init_done;
+	struct zcomp *comp;
+
 	/* Prevent concurrent execution of device init, reset and R/W request */
 	struct rw_semaphore init_lock;
 	/*
@@ -106,19 +111,13 @@ struct zram {
 	 * we can store in a disk.
 	 */
 	u64 disksize;	/* bytes */
-
+	int max_comp_streams;
 	struct zram_stats stats;
-};
-
-extern struct zram *zram_devices;
-unsigned int zram_get_num_devices(void);
-#ifdef CONFIG_SYSFS
-extern struct attribute_group zram_disk_attr_group;
-#endif
-
-extern void zram_reset_device(struct zram *zram);
-extern struct zram_meta *zram_meta_alloc(u64 disksize);
-extern void zram_meta_free(struct zram_meta *meta);
-extern void zram_init_device(struct zram *zram, struct zram_meta *meta);
+	/*
+	 * the number of pages zram can consume for storing compressed data
+	 */
+	unsigned long limit_pages;
 
+	char compressor[10];
+};
 #endif
diff --git a/drivers/staging/Kconfig b/drivers/staging/Kconfig
index aefe820a8005..25c8bffdd248 100644
--- a/drivers/staging/Kconfig
+++ b/drivers/staging/Kconfig
@@ -72,10 +72,6 @@ source "drivers/staging/sep/Kconfig"
 
 source "drivers/staging/iio/Kconfig"
 
-source "drivers/staging/zsmalloc/Kconfig"
-
-source "drivers/staging/zram/Kconfig"
-
 source "drivers/staging/wlags49_h2/Kconfig"
 
 source "drivers/staging/wlags49_h25/Kconfig"
diff --git a/drivers/staging/Makefile b/drivers/staging/Makefile
index 415772ea306d..f9d86a4b48e9 100644
--- a/drivers/staging/Makefile
+++ b/drivers/staging/Makefile
@@ -30,8 +30,6 @@ obj-$(CONFIG_VT6656)		+= vt6656/
 obj-$(CONFIG_VME_BUS)		+= vme/
 obj-$(CONFIG_DX_SEP)            += sep/
 obj-$(CONFIG_IIO)		+= iio/
-obj-$(CONFIG_ZRAM)		+= zram/
-obj-$(CONFIG_ZSMALLOC)		+= zsmalloc/
 obj-$(CONFIG_WLAGS49_H2)	+= wlags49_h2/
 obj-$(CONFIG_WLAGS49_H25)	+= wlags49_h25/
 obj-$(CONFIG_FB_SM7XX)		+= sm7xxfb/
diff --git a/drivers/staging/zram/Makefile b/drivers/staging/zram/Makefile
deleted file mode 100644
index 7f4a3019e9c4..000000000000
--- a/drivers/staging/zram/Makefile
+++ /dev/null
@@ -1,3 +0,0 @@
-zram-y	:=	zram_drv.o zram_sysfs.o
-
-obj-$(CONFIG_ZRAM)	+=	zram.o
diff --git a/drivers/staging/zram/zram.txt b/drivers/staging/zram/zram.txt
deleted file mode 100644
index 765d790ae831..000000000000
--- a/drivers/staging/zram/zram.txt
+++ /dev/null
@@ -1,77 +0,0 @@
-zram: Compressed RAM based block devices
-----------------------------------------
-
-Project home: http://compcache.googlecode.com/
-
-* Introduction
-
-The zram module creates RAM based block devices named /dev/zram<id>
-(<id> = 0, 1, ...). Pages written to these disks are compressed and stored
-in memory itself. These disks allow very fast I/O and compression provides
-good amounts of memory savings. Some of the usecases include /tmp storage,
-use as swap disks, various caches under /var and maybe many more :)
-
-Statistics for individual zram devices are exported through sysfs nodes at
-/sys/block/zram<id>/
-
-* Usage
-
-Following shows a typical sequence of steps for using zram.
-
-1) Load Module:
-	modprobe zram num_devices=4
-	This creates 4 devices: /dev/zram{0,1,2,3}
-	(num_devices parameter is optional. Default: 1)
-
-2) Set Disksize
-        Set disk size by writing the value to sysfs node 'disksize'.
-        The value can be either in bytes or you can use mem suffixes.
-        Examples:
-            # Initialize /dev/zram0 with 50MB disksize
-            echo $((50*1024*1024)) > /sys/block/zram0/disksize
-
-            # Using mem suffixes
-            echo 256K > /sys/block/zram0/disksize
-            echo 512M > /sys/block/zram0/disksize
-            echo 1G > /sys/block/zram0/disksize
-
-3) Activate:
-	mkswap /dev/zram0
-	swapon /dev/zram0
-
-	mkfs.ext4 /dev/zram1
-	mount /dev/zram1 /tmp
-
-4) Stats:
-	Per-device statistics are exported as various nodes under
-	/sys/block/zram<id>/
-		disksize
-		num_reads
-		num_writes
-		invalid_io
-		notify_free
-		discard
-		zero_pages
-		orig_data_size
-		compr_data_size
-		mem_used_total
-
-5) Deactivate:
-	swapoff /dev/zram0
-	umount /dev/zram1
-
-6) Reset:
-	Write any positive value to 'reset' sysfs node
-	echo 1 > /sys/block/zram0/reset
-	echo 1 > /sys/block/zram1/reset
-
-	This frees all the memory allocated for the given device and
-	resets the disksize to zero. You must set the disksize again
-	before reusing the device.
-
-Please report any problems at:
- - Mailing list: linux-mm-cc at laptop dot org
- - Issue tracker: http://code.google.com/p/compcache/issues/list
-
-Nitin Gupta
-ngupta@vflare.org
diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c
deleted file mode 100644
index a333d44d0cff..000000000000
--- a/drivers/staging/zram/zram_drv.c
+++ /dev/null
@@ -1,760 +0,0 @@
-/*
- * Compressed RAM block device
- *
- * Copyright (C) 2008, 2009, 2010  Nitin Gupta
- *
- * 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
- *
- * Project home: http://compcache.googlecode.com
- */
-
-#define KMSG_COMPONENT "zram"
-#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
-
-#ifdef CONFIG_ZRAM_DEBUG
-#define DEBUG
-#endif
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/bio.h>
-#include <linux/bitops.h>
-#include <linux/blkdev.h>
-#include <linux/buffer_head.h>
-#include <linux/device.h>
-#include <linux/genhd.h>
-#include <linux/highmem.h>
-#include <linux/slab.h>
-#include <linux/lzo.h>
-#include <linux/string.h>
-#include <linux/vmalloc.h>
-
-#include "zram_drv.h"
-
-/* Globals */
-static int zram_major;
-struct zram *zram_devices;
-
-/* Module params (documentation at end) */
-static unsigned int num_devices = 1;
-
-static void zram_stat64_add(struct zram *zram, u64 *v, u64 inc)
-{
-	spin_lock(&zram->stat64_lock);
-	*v = *v + inc;
-	spin_unlock(&zram->stat64_lock);
-}
-
-static void zram_stat64_sub(struct zram *zram, u64 *v, u64 dec)
-{
-	spin_lock(&zram->stat64_lock);
-	*v = *v - dec;
-	spin_unlock(&zram->stat64_lock);
-}
-
-static void zram_stat64_inc(struct zram *zram, u64 *v)
-{
-	zram_stat64_add(zram, v, 1);
-}
-
-static int zram_test_flag(struct zram_meta *meta, u32 index,
-			enum zram_pageflags flag)
-{
-	return meta->table[index].flags & BIT(flag);
-}
-
-static void zram_set_flag(struct zram_meta *meta, u32 index,
-			enum zram_pageflags flag)
-{
-	meta->table[index].flags |= BIT(flag);
-}
-
-static void zram_clear_flag(struct zram_meta *meta, u32 index,
-			enum zram_pageflags flag)
-{
-	meta->table[index].flags &= ~BIT(flag);
-}
-
-static int page_zero_filled(void *ptr)
-{
-	unsigned int pos;
-	unsigned long *page;
-
-	page = (unsigned long *)ptr;
-
-	for (pos = 0; pos != PAGE_SIZE / sizeof(*page); pos++) {
-		if (page[pos])
-			return 0;
-	}
-
-	return 1;
-}
-
-static void zram_free_page(struct zram *zram, size_t index)
-{
-	struct zram_meta *meta = zram->meta;
-	unsigned long handle = meta->table[index].handle;
-	u16 size = meta->table[index].size;
-
-	if (unlikely(!handle)) {
-		/*
-		 * No memory is allocated for zero filled pages.
-		 * Simply clear zero page flag.
-		 */
-		if (zram_test_flag(meta, index, ZRAM_ZERO)) {
-			zram_clear_flag(meta, index, ZRAM_ZERO);
-			zram->stats.pages_zero--;
-		}
-		return;
-	}
-
-	if (unlikely(size > max_zpage_size))
-		zram->stats.bad_compress--;
-
-	zs_free(meta->mem_pool, handle);
-
-	if (size <= PAGE_SIZE / 2)
-		zram->stats.good_compress--;
-
-	zram_stat64_sub(zram, &zram->stats.compr_size,
-			meta->table[index].size);
-	zram->stats.pages_stored--;
-
-	meta->table[index].handle = 0;
-	meta->table[index].size = 0;
-}
-
-static void handle_zero_page(struct bio_vec *bvec)
-{
-	struct page *page = bvec->bv_page;
-	void *user_mem;
-
-	user_mem = kmap_atomic(page);
-	memset(user_mem + bvec->bv_offset, 0, bvec->bv_len);
-	kunmap_atomic(user_mem);
-
-	flush_dcache_page(page);
-}
-
-static inline int is_partial_io(struct bio_vec *bvec)
-{
-	return bvec->bv_len != PAGE_SIZE;
-}
-
-static int zram_decompress_page(struct zram *zram, char *mem, u32 index)
-{
-	int ret = LZO_E_OK;
-	size_t clen = PAGE_SIZE;
-	unsigned char *cmem;
-	struct zram_meta *meta = zram->meta;
-	unsigned long handle = meta->table[index].handle;
-
-	if (!handle || zram_test_flag(meta, index, ZRAM_ZERO)) {
-		memset(mem, 0, PAGE_SIZE);
-		return 0;
-	}
-
-	cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_RO);
-	if (meta->table[index].size == PAGE_SIZE)
-		memcpy(mem, cmem, PAGE_SIZE);
-	else
-		ret = lzo1x_decompress_safe(cmem, meta->table[index].size,
-						mem, &clen);
-	zs_unmap_object(meta->mem_pool, handle);
-
-	/* Should NEVER happen. Return bio error if it does. */
-	if (unlikely(ret != LZO_E_OK)) {
-		pr_err("Decompression failed! err=%d, page=%u\n", ret, index);
-		zram_stat64_inc(zram, &zram->stats.failed_reads);
-		return ret;
-	}
-
-	return 0;
-}
-
-static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
-			  u32 index, int offset, struct bio *bio)
-{
-	int ret;
-	struct page *page;
-	unsigned char *user_mem, *uncmem = NULL;
-	struct zram_meta *meta = zram->meta;
-	page = bvec->bv_page;
-
-	if (unlikely(!meta->table[index].handle) ||
-			zram_test_flag(meta, index, ZRAM_ZERO)) {
-		handle_zero_page(bvec);
-		return 0;
-	}
-
-	if (is_partial_io(bvec))
-		/* Use  a temporary buffer to decompress the page */
-		uncmem = kmalloc(PAGE_SIZE, GFP_NOIO);
-
-	user_mem = kmap_atomic(page);
-	if (!is_partial_io(bvec))
-		uncmem = user_mem;
-
-	if (!uncmem) {
-		pr_info("Unable to allocate temp memory\n");
-		ret = -ENOMEM;
-		goto out_cleanup;
-	}
-
-	ret = zram_decompress_page(zram, uncmem, index);
-	/* Should NEVER happen. Return bio error if it does. */
-	if (unlikely(ret != LZO_E_OK))
-		goto out_cleanup;
-
-	if (is_partial_io(bvec))
-		memcpy(user_mem + bvec->bv_offset, uncmem + offset,
-				bvec->bv_len);
-
-	flush_dcache_page(page);
-	ret = 0;
-out_cleanup:
-	kunmap_atomic(user_mem);
-	if (is_partial_io(bvec))
-		kfree(uncmem);
-	return ret;
-}
-
-static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
-			   int offset)
-{
-	int ret = 0;
-	size_t clen;
-	unsigned long handle;
-	struct page *page;
-	unsigned char *user_mem, *cmem, *src, *uncmem = NULL;
-	struct zram_meta *meta = zram->meta;
-
-	page = bvec->bv_page;
-	src = meta->compress_buffer;
-
-	if (is_partial_io(bvec)) {
-		/*
-		 * This is a partial IO. We need to read the full page
-		 * before to write the changes.
-		 */
-		uncmem = kmalloc(PAGE_SIZE, GFP_NOIO);
-		if (!uncmem) {
-			ret = -ENOMEM;
-			goto out;
-		}
-		ret = zram_decompress_page(zram, uncmem, index);
-		if (ret)
-			goto out;
-	}
-
-	/*
-	 * System overwrites unused sectors. Free memory associated
-	 * with this sector now.
-	 */
-	if (meta->table[index].handle ||
-	    zram_test_flag(meta, index, ZRAM_ZERO))
-		zram_free_page(zram, index);
-
-	user_mem = kmap_atomic(page);
-
-	if (is_partial_io(bvec)) {
-		memcpy(uncmem + offset, user_mem + bvec->bv_offset,
-		       bvec->bv_len);
-		kunmap_atomic(user_mem);
-		user_mem = NULL;
-	} else {
-		uncmem = user_mem;
-	}
-
-	if (page_zero_filled(uncmem)) {
-		kunmap_atomic(user_mem);
-		zram->stats.pages_zero++;
-		zram_set_flag(meta, index, ZRAM_ZERO);
-		ret = 0;
-		goto out;
-	}
-
-	ret = lzo1x_1_compress(uncmem, PAGE_SIZE, src, &clen,
-			       meta->compress_workmem);
-
-	if (!is_partial_io(bvec)) {
-		kunmap_atomic(user_mem);
-		user_mem = NULL;
-		uncmem = NULL;
-	}
-
-	if (unlikely(ret != LZO_E_OK)) {
-		pr_err("Compression failed! err=%d\n", ret);
-		goto out;
-	}
-
-	if (unlikely(clen > max_zpage_size)) {
-		zram->stats.bad_compress++;
-		clen = PAGE_SIZE;
-		src = NULL;
-		if (is_partial_io(bvec))
-			src = uncmem;
-	}
-
-	handle = zs_malloc(meta->mem_pool, clen);
-	if (!handle) {
-		pr_info("Error allocating memory for compressed "
-			"page: %u, size=%zu\n", index, clen);
-		ret = -ENOMEM;
-		goto out;
-	}
-	cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_WO);
-
-	if ((clen == PAGE_SIZE) && !is_partial_io(bvec))
-		src = kmap_atomic(page);
-	memcpy(cmem, src, clen);
-	if ((clen == PAGE_SIZE) && !is_partial_io(bvec))
-		kunmap_atomic(src);
-
-	zs_unmap_object(meta->mem_pool, handle);
-
-	meta->table[index].handle = handle;
-	meta->table[index].size = clen;
-
-	/* Update stats */
-	zram_stat64_add(zram, &zram->stats.compr_size, clen);
-	zram->stats.pages_stored++;
-	if (clen <= PAGE_SIZE / 2)
-		zram->stats.good_compress++;
-
-out:
-	if (is_partial_io(bvec))
-		kfree(uncmem);
-
-	if (ret)
-		zram_stat64_inc(zram, &zram->stats.failed_writes);
-	return ret;
-}
-
-static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index,
-			int offset, struct bio *bio, int rw)
-{
-	int ret;
-
-	if (rw == READ) {
-		down_read(&zram->lock);
-		ret = zram_bvec_read(zram, bvec, index, offset, bio);
-		up_read(&zram->lock);
-	} else {
-		down_write(&zram->lock);
-		ret = zram_bvec_write(zram, bvec, index, offset);
-		up_write(&zram->lock);
-	}
-
-	return ret;
-}
-
-static void update_position(u32 *index, int *offset, struct bio_vec *bvec)
-{
-	if (*offset + bvec->bv_len >= PAGE_SIZE)
-		(*index)++;
-	*offset = (*offset + bvec->bv_len) % PAGE_SIZE;
-}
-
-static void __zram_make_request(struct zram *zram, struct bio *bio, int rw)
-{
-	int i, offset;
-	u32 index;
-	struct bio_vec *bvec;
-
-	switch (rw) {
-	case READ:
-		zram_stat64_inc(zram, &zram->stats.num_reads);
-		break;
-	case WRITE:
-		zram_stat64_inc(zram, &zram->stats.num_writes);
-		break;
-	}
-
-	index = bio->bi_sector >> SECTORS_PER_PAGE_SHIFT;
-	offset = (bio->bi_sector & (SECTORS_PER_PAGE - 1)) << SECTOR_SHIFT;
-
-	bio_for_each_segment(bvec, bio, i) {
-		int max_transfer_size = PAGE_SIZE - offset;
-
-		if (bvec->bv_len > max_transfer_size) {
-			/*
-			 * zram_bvec_rw() can only make operation on a single
-			 * zram page. Split the bio vector.
-			 */
-			struct bio_vec bv;
-
-			bv.bv_page = bvec->bv_page;
-			bv.bv_len = max_transfer_size;
-			bv.bv_offset = bvec->bv_offset;
-
-			if (zram_bvec_rw(zram, &bv, index, offset, bio, rw) < 0)
-				goto out;
-
-			bv.bv_len = bvec->bv_len - max_transfer_size;
-			bv.bv_offset += max_transfer_size;
-			if (zram_bvec_rw(zram, &bv, index+1, 0, bio, rw) < 0)
-				goto out;
-		} else
-			if (zram_bvec_rw(zram, bvec, index, offset, bio, rw)
-			    < 0)
-				goto out;
-
-		update_position(&index, &offset, bvec);
-	}
-
-	set_bit(BIO_UPTODATE, &bio->bi_flags);
-	bio_endio(bio, 0);
-	return;
-
-out:
-	bio_io_error(bio);
-}
-
-/*
- * Check if request is within bounds and aligned on zram logical blocks.
- */
-static inline int valid_io_request(struct zram *zram, struct bio *bio)
-{
-	u64 start, end, bound;
-
-	/* unaligned request */
-	if (unlikely(bio->bi_sector & (ZRAM_SECTOR_PER_LOGICAL_BLOCK - 1)))
-		return 0;
-	if (unlikely(bio->bi_size & (ZRAM_LOGICAL_BLOCK_SIZE - 1)))
-		return 0;
-
-	start = bio->bi_sector;
-	end = start + (bio->bi_size >> SECTOR_SHIFT);
-	bound = zram->disksize >> SECTOR_SHIFT;
-	/* out of range range */
-	if (unlikely(start >= bound || end > bound || start > end))
-		return 0;
-
-	/* I/O request is valid */
-	return 1;
-}
-
-/*
- * Handler function for all zram I/O requests.
- */
-static void zram_make_request(struct request_queue *queue, struct bio *bio)
-{
-	struct zram *zram = queue->queuedata;
-
-	down_read(&zram->init_lock);
-	if (unlikely(!zram->init_done))
-		goto error;
-
-	if (!valid_io_request(zram, bio)) {
-		zram_stat64_inc(zram, &zram->stats.invalid_io);
-		goto error;
-	}
-
-	__zram_make_request(zram, bio, bio_data_dir(bio));
-	up_read(&zram->init_lock);
-
-	return;
-
-error:
-	up_read(&zram->init_lock);
-	bio_io_error(bio);
-}
-
-static void __zram_reset_device(struct zram *zram)
-{
-	size_t index;
-	struct zram_meta *meta;
-
-	if (!zram->init_done)
-		return;
-
-	meta = zram->meta;
-	zram->init_done = 0;
-
-	/* Free all pages that are still in this zram device */
-	for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) {
-		unsigned long handle = meta->table[index].handle;
-		if (!handle)
-			continue;
-
-		zs_free(meta->mem_pool, handle);
-	}
-
-	zram_meta_free(zram->meta);
-	zram->meta = NULL;
-	/* Reset stats */
-	memset(&zram->stats, 0, sizeof(zram->stats));
-
-	zram->disksize = 0;
-	set_capacity(zram->disk, 0);
-}
-
-void zram_reset_device(struct zram *zram)
-{
-	down_write(&zram->init_lock);
-	__zram_reset_device(zram);
-	up_write(&zram->init_lock);
-}
-
-void zram_meta_free(struct zram_meta *meta)
-{
-	zs_destroy_pool(meta->mem_pool);
-	kfree(meta->compress_workmem);
-	free_pages((unsigned long)meta->compress_buffer, 1);
-	vfree(meta->table);
-	kfree(meta);
-}
-
-struct zram_meta *zram_meta_alloc(u64 disksize)
-{
-	size_t num_pages;
-	struct zram_meta *meta = kmalloc(sizeof(*meta), GFP_KERNEL);
-	if (!meta)
-		goto out;
-
-	meta->compress_workmem = kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
-	if (!meta->compress_workmem)
-		goto free_meta;
-
-	meta->compress_buffer =
-		(void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
-	if (!meta->compress_buffer) {
-		pr_err("Error allocating compressor buffer space\n");
-		goto free_workmem;
-	}
-
-	num_pages = disksize >> PAGE_SHIFT;
-	meta->table = vzalloc(num_pages * sizeof(*meta->table));
-	if (!meta->table) {
-		pr_err("Error allocating zram address table\n");
-		goto free_buffer;
-	}
-
-	meta->mem_pool = zs_create_pool(GFP_NOIO | __GFP_HIGHMEM);
-	if (!meta->mem_pool) {
-		pr_err("Error creating memory pool\n");
-		goto free_table;
-	}
-
-	return meta;
-
-free_table:
-	vfree(meta->table);
-free_buffer:
-	free_pages((unsigned long)meta->compress_buffer, 1);
-free_workmem:
-	kfree(meta->compress_workmem);
-free_meta:
-	kfree(meta);
-	meta = NULL;
-out:
-	return meta;
-}
-
-void zram_init_device(struct zram *zram, struct zram_meta *meta)
-{
-	if (zram->disksize > 2 * (totalram_pages << PAGE_SHIFT)) {
-		pr_info(
-		"There is little point creating a zram of greater than "
-		"twice the size of memory since we expect a 2:1 compression "
-		"ratio. Note that zram uses about 0.1%% of the size of "
-		"the disk when not in use so a huge zram is "
-		"wasteful.\n"
-		"\tMemory Size: %lu kB\n"
-		"\tSize you selected: %llu kB\n"
-		"Continuing anyway ...\n",
-		(totalram_pages << PAGE_SHIFT) >> 10, zram->disksize >> 10
-		);
-	}
-
-	/* zram devices sort of resembles non-rotational disks */
-	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue);
-
-	zram->meta = meta;
-	zram->init_done = 1;
-
-	pr_debug("Initialization done!\n");
-}
-
-static void zram_slot_free_notify(struct block_device *bdev,
-				unsigned long index)
-{
-	struct zram *zram;
-
-	zram = bdev->bd_disk->private_data;
-	down_write(&zram->lock);
-	zram_free_page(zram, index);
-	up_write(&zram->lock);
-	zram_stat64_inc(zram, &zram->stats.notify_free);
-}
-
-static const struct block_device_operations zram_devops = {
-	.swap_slot_free_notify = zram_slot_free_notify,
-	.owner = THIS_MODULE
-};
-
-static int create_device(struct zram *zram, int device_id)
-{
-	int ret = -ENOMEM;
-
-	init_rwsem(&zram->lock);
-	init_rwsem(&zram->init_lock);
-	spin_lock_init(&zram->stat64_lock);
-
-	zram->queue = blk_alloc_queue(GFP_KERNEL);
-	if (!zram->queue) {
-		pr_err("Error allocating disk queue for device %d\n",
-			device_id);
-		goto out;
-	}
-
-	blk_queue_make_request(zram->queue, zram_make_request);
-	zram->queue->queuedata = zram;
-
-	 /* gendisk structure */
-	zram->disk = alloc_disk(1);
-	if (!zram->disk) {
-		pr_warn("Error allocating disk structure for device %d\n",
-			device_id);
-		goto out_free_queue;
-	}
-
-	zram->disk->major = zram_major;
-	zram->disk->first_minor = device_id;
-	zram->disk->fops = &zram_devops;
-	zram->disk->queue = zram->queue;
-	zram->disk->private_data = zram;
-	snprintf(zram->disk->disk_name, 16, "zram%d", device_id);
-
-	/* Actual capacity set using syfs (/sys/block/zram<id>/disksize */
-	set_capacity(zram->disk, 0);
-
-	/*
-	 * To ensure that we always get PAGE_SIZE aligned
-	 * and n*PAGE_SIZED sized I/O requests.
-	 */
-	blk_queue_physical_block_size(zram->disk->queue, PAGE_SIZE);
-	blk_queue_logical_block_size(zram->disk->queue,
-					ZRAM_LOGICAL_BLOCK_SIZE);
-	blk_queue_io_min(zram->disk->queue, PAGE_SIZE);
-	blk_queue_io_opt(zram->disk->queue, PAGE_SIZE);
-
-	add_disk(zram->disk);
-
-	ret = sysfs_create_group(&disk_to_dev(zram->disk)->kobj,
-				&zram_disk_attr_group);
-	if (ret < 0) {
-		pr_warn("Error creating sysfs group");
-		goto out_free_disk;
-	}
-
-	zram->init_done = 0;
-	return 0;
-
-out_free_disk:
-	del_gendisk(zram->disk);
-	put_disk(zram->disk);
-out_free_queue:
-	blk_cleanup_queue(zram->queue);
-out:
-	return ret;
-}
-
-static void destroy_device(struct zram *zram)
-{
-	sysfs_remove_group(&disk_to_dev(zram->disk)->kobj,
-			&zram_disk_attr_group);
-
-	if (zram->disk) {
-		del_gendisk(zram->disk);
-		put_disk(zram->disk);
-	}
-
-	if (zram->queue)
-		blk_cleanup_queue(zram->queue);
-}
-
-unsigned int zram_get_num_devices(void)
-{
-	return num_devices;
-}
-
-static int __init zram_init(void)
-{
-	int ret, dev_id;
-
-	if (num_devices > max_num_devices) {
-		pr_warn("Invalid value for num_devices: %u\n",
-				num_devices);
-		ret = -EINVAL;
-		goto out;
-	}
-
-	zram_major = register_blkdev(0, "zram");
-	if (zram_major <= 0) {
-		pr_warn("Unable to get major number\n");
-		ret = -EBUSY;
-		goto out;
-	}
-
-	/* Allocate the device array and initialize each one */
-	zram_devices = kzalloc(num_devices * sizeof(struct zram), GFP_KERNEL);
-	if (!zram_devices) {
-		ret = -ENOMEM;
-		goto unregister;
-	}
-
-	for (dev_id = 0; dev_id < num_devices; dev_id++) {
-		ret = create_device(&zram_devices[dev_id], dev_id);
-		if (ret)
-			goto free_devices;
-	}
-
-	pr_info("Created %u device(s) ...\n", num_devices);
-
-	return 0;
-
-free_devices:
-	while (dev_id)
-		destroy_device(&zram_devices[--dev_id]);
-	kfree(zram_devices);
-unregister:
-	unregister_blkdev(zram_major, "zram");
-out:
-	return ret;
-}
-
-static void __exit zram_exit(void)
-{
-	int i;
-	struct zram *zram;
-
-	for (i = 0; i < num_devices; i++) {
-		zram = &zram_devices[i];
-
-		get_disk(zram->disk);
-		destroy_device(zram);
-		zram_reset_device(zram);
-		put_disk(zram->disk);
-	}
-
-	unregister_blkdev(zram_major, "zram");
-
-	kfree(zram_devices);
-	pr_debug("Cleanup done!\n");
-}
-
-module_param(num_devices, uint, 0);
-MODULE_PARM_DESC(num_devices, "Number of zram devices");
-
-module_init(zram_init);
-module_exit(zram_exit);
-
-MODULE_LICENSE("Dual BSD/GPL");
-MODULE_AUTHOR("Nitin Gupta <ngupta@vflare.org>");
-MODULE_DESCRIPTION("Compressed RAM Block Device");
diff --git a/drivers/staging/zram/zram_sysfs.c b/drivers/staging/zram/zram_sysfs.c
deleted file mode 100644
index dc76a3dba1b8..000000000000
--- a/drivers/staging/zram/zram_sysfs.c
+++ /dev/null
@@ -1,229 +0,0 @@
-/*
- * Compressed RAM block device
- *
- * Copyright (C) 2008, 2009, 2010  Nitin Gupta
- *
- * 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
- *
- * Project home: http://compcache.googlecode.com/
- */
-
-#include <linux/device.h>
-#include <linux/genhd.h>
-#include <linux/mm.h>
-#include <linux/kernel.h>
-
-#include "zram_drv.h"
-
-static u64 zram_stat64_read(struct zram *zram, u64 *v)
-{
-	u64 val;
-
-	spin_lock(&zram->stat64_lock);
-	val = *v;
-	spin_unlock(&zram->stat64_lock);
-
-	return val;
-}
-
-static struct zram *dev_to_zram(struct device *dev)
-{
-	int i;
-	struct zram *zram = NULL;
-
-	for (i = 0; i < zram_get_num_devices(); i++) {
-		zram = &zram_devices[i];
-		if (disk_to_dev(zram->disk) == dev)
-			break;
-	}
-
-	return zram;
-}
-
-static ssize_t disksize_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct zram *zram = dev_to_zram(dev);
-
-	return sprintf(buf, "%llu\n", zram->disksize);
-}
-
-static ssize_t disksize_store(struct device *dev,
-		struct device_attribute *attr, const char *buf, size_t len)
-{
-	u64 disksize;
-	struct zram_meta *meta;
-	struct zram *zram = dev_to_zram(dev);
-
-	disksize = memparse(buf, NULL);
-	if (!disksize)
-		return -EINVAL;
-
-	disksize = PAGE_ALIGN(disksize);
-	meta = zram_meta_alloc(disksize);
-	down_write(&zram->init_lock);
-	if (zram->init_done) {
-		up_write(&zram->init_lock);
-		zram_meta_free(meta);
-		pr_info("Cannot change disksize for initialized device\n");
-		return -EBUSY;
-	}
-
-	zram->disksize = disksize;
-	set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
-	zram_init_device(zram, meta);
-	up_write(&zram->init_lock);
-
-	return len;
-}
-
-static ssize_t initstate_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct zram *zram = dev_to_zram(dev);
-
-	return sprintf(buf, "%u\n", zram->init_done);
-}
-
-static ssize_t reset_store(struct device *dev,
-		struct device_attribute *attr, const char *buf, size_t len)
-{
-	int ret;
-	unsigned short do_reset;
-	struct zram *zram;
-	struct block_device *bdev;
-
-	zram = dev_to_zram(dev);
-	bdev = bdget_disk(zram->disk, 0);
-
-	/* Do not reset an active device! */
-	if (bdev->bd_holders)
-		return -EBUSY;
-
-	ret = kstrtou16(buf, 10, &do_reset);
-	if (ret)
-		return ret;
-
-	if (!do_reset)
-		return -EINVAL;
-
-	/* Make sure all pending I/O is finished */
-	if (bdev)
-		fsync_bdev(bdev);
-
-	zram_reset_device(zram);
-	return len;
-}
-
-static ssize_t num_reads_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct zram *zram = dev_to_zram(dev);
-
-	return sprintf(buf, "%llu\n",
-		zram_stat64_read(zram, &zram->stats.num_reads));
-}
-
-static ssize_t num_writes_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct zram *zram = dev_to_zram(dev);
-
-	return sprintf(buf, "%llu\n",
-		zram_stat64_read(zram, &zram->stats.num_writes));
-}
-
-static ssize_t invalid_io_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct zram *zram = dev_to_zram(dev);
-
-	return sprintf(buf, "%llu\n",
-		zram_stat64_read(zram, &zram->stats.invalid_io));
-}
-
-static ssize_t notify_free_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct zram *zram = dev_to_zram(dev);
-
-	return sprintf(buf, "%llu\n",
-		zram_stat64_read(zram, &zram->stats.notify_free));
-}
-
-static ssize_t zero_pages_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct zram *zram = dev_to_zram(dev);
-
-	return sprintf(buf, "%u\n", zram->stats.pages_zero);
-}
-
-static ssize_t orig_data_size_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct zram *zram = dev_to_zram(dev);
-
-	return sprintf(buf, "%llu\n",
-		(u64)(zram->stats.pages_stored) << PAGE_SHIFT);
-}
-
-static ssize_t compr_data_size_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct zram *zram = dev_to_zram(dev);
-
-	return sprintf(buf, "%llu\n",
-		zram_stat64_read(zram, &zram->stats.compr_size));
-}
-
-static ssize_t mem_used_total_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	u64 val = 0;
-	struct zram *zram = dev_to_zram(dev);
-	struct zram_meta *meta = zram->meta;
-
-	down_read(&zram->init_lock);
-	if (zram->init_done)
-		val = zs_get_total_size_bytes(meta->mem_pool);
-	up_read(&zram->init_lock);
-
-	return sprintf(buf, "%llu\n", val);
-}
-
-static DEVICE_ATTR(disksize, S_IRUGO | S_IWUSR,
-		disksize_show, disksize_store);
-static DEVICE_ATTR(initstate, S_IRUGO, initstate_show, NULL);
-static DEVICE_ATTR(reset, S_IWUSR, NULL, reset_store);
-static DEVICE_ATTR(num_reads, S_IRUGO, num_reads_show, NULL);
-static DEVICE_ATTR(num_writes, S_IRUGO, num_writes_show, NULL);
-static DEVICE_ATTR(invalid_io, S_IRUGO, invalid_io_show, NULL);
-static DEVICE_ATTR(notify_free, S_IRUGO, notify_free_show, NULL);
-static DEVICE_ATTR(zero_pages, S_IRUGO, zero_pages_show, NULL);
-static DEVICE_ATTR(orig_data_size, S_IRUGO, orig_data_size_show, NULL);
-static DEVICE_ATTR(compr_data_size, S_IRUGO, compr_data_size_show, NULL);
-static DEVICE_ATTR(mem_used_total, S_IRUGO, mem_used_total_show, NULL);
-
-static struct attribute *zram_disk_attrs[] = {
-	&dev_attr_disksize.attr,
-	&dev_attr_initstate.attr,
-	&dev_attr_reset.attr,
-	&dev_attr_num_reads.attr,
-	&dev_attr_num_writes.attr,
-	&dev_attr_invalid_io.attr,
-	&dev_attr_notify_free.attr,
-	&dev_attr_zero_pages.attr,
-	&dev_attr_orig_data_size.attr,
-	&dev_attr_compr_data_size.attr,
-	&dev_attr_mem_used_total.attr,
-	NULL,
-};
-
-struct attribute_group zram_disk_attr_group = {
-	.attrs = zram_disk_attrs,
-};
diff --git a/drivers/staging/zsmalloc/Makefile b/drivers/staging/zsmalloc/Makefile
deleted file mode 100644
index b134848a590d..000000000000
--- a/drivers/staging/zsmalloc/Makefile
+++ /dev/null
@@ -1,3 +0,0 @@
-zsmalloc-y 		:= zsmalloc-main.o
-
-obj-$(CONFIG_ZSMALLOC)	+= zsmalloc.o
diff --git a/drivers/staging/zsmalloc/zsmalloc-main.c b/drivers/staging/zsmalloc/zsmalloc-main.c
deleted file mode 100644
index 288f58252a18..000000000000
--- a/drivers/staging/zsmalloc/zsmalloc-main.c
+++ /dev/null
@@ -1,1073 +0,0 @@
-/*
- * zsmalloc memory allocator
- *
- * Copyright (C) 2011  Nitin Gupta
- *
- * This code is released using a dual license strategy: BSD/GPL
- * You can choose the license 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
- */
-
-
-/*
- * This allocator is designed for use with zcache and zram. Thus, the
- * allocator is supposed to work well under low memory conditions. In
- * particular, it never attempts higher order page allocation which is
- * very likely to fail under memory pressure. On the other hand, if we
- * just use single (0-order) pages, it would suffer from very high
- * fragmentation -- any object of size PAGE_SIZE/2 or larger would occupy
- * an entire page. This was one of the major issues with its predecessor
- * (xvmalloc).
- *
- * To overcome these issues, zsmalloc allocates a bunch of 0-order pages
- * and links them together using various 'struct page' fields. These linked
- * pages act as a single higher-order page i.e. an object can span 0-order
- * page boundaries. The code refers to these linked pages as a single entity
- * called zspage.
- *
- * Following is how we use various fields and flags of underlying
- * struct page(s) to form a zspage.
- *
- * Usage of struct page fields:
- *	page->first_page: points to the first component (0-order) page
- *	page->index (union with page->freelist): offset of the first object
- *		starting in this page. For the first page, this is
- *		always 0, so we use this field (aka freelist) to point
- *		to the first free object in zspage.
- *	page->lru: links together all component pages (except the first page)
- *		of a zspage
- *
- *	For _first_ page only:
- *
- *	page->private (union with page->first_page): refers to the
- *		component page after the first page
- *	page->freelist: points to the first free object in zspage.
- *		Free objects are linked together using in-place
- *		metadata.
- *	page->objects: maximum number of objects we can store in this
- *		zspage (class->zspage_order * PAGE_SIZE / class->size)
- *	page->lru: links together first pages of various zspages.
- *		Basically forming list of zspages in a fullness group.
- *	page->mapping: class index and fullness group of the zspage
- *
- * Usage of struct page flags:
- *	PG_private: identifies the first component page
- *	PG_private2: identifies the last component page
- *
- */
-
-#ifdef CONFIG_ZSMALLOC_DEBUG
-#define DEBUG
-#endif
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/bitops.h>
-#include <linux/errno.h>
-#include <linux/highmem.h>
-#include <linux/init.h>
-#include <linux/string.h>
-#include <linux/slab.h>
-#include <asm/tlbflush.h>
-#include <asm/pgtable.h>
-#include <linux/cpumask.h>
-#include <linux/cpu.h>
-#include <linux/vmalloc.h>
-#include <linux/hardirq.h>
-#include <linux/spinlock.h>
-#include <linux/types.h>
-
-#include "zsmalloc.h"
-
-/*
- * This must be power of 2 and greater than of equal to sizeof(link_free).
- * These two conditions ensure that any 'struct link_free' itself doesn't
- * span more than 1 page which avoids complex case of mapping 2 pages simply
- * to restore link_free pointer values.
- */
-#define ZS_ALIGN		8
-
-/*
- * A single 'zspage' is composed of up to 2^N discontiguous 0-order (single)
- * pages. ZS_MAX_ZSPAGE_ORDER defines upper limit on N.
- */
-#define ZS_MAX_ZSPAGE_ORDER 2
-#define ZS_MAX_PAGES_PER_ZSPAGE (_AC(1, UL) << ZS_MAX_ZSPAGE_ORDER)
-
-/*
- * Object location (<PFN>, <obj_idx>) is encoded as
- * as single (void *) handle value.
- *
- * Note that object index <obj_idx> is relative to system
- * page <PFN> it is stored in, so for each sub-page belonging
- * to a zspage, obj_idx starts with 0.
- *
- * This is made more complicated by various memory models and PAE.
- */
-
-#ifndef MAX_PHYSMEM_BITS
-#ifdef CONFIG_HIGHMEM64G
-#define MAX_PHYSMEM_BITS 36
-#else /* !CONFIG_HIGHMEM64G */
-/*
- * If this definition of MAX_PHYSMEM_BITS is used, OBJ_INDEX_BITS will just
- * be PAGE_SHIFT
- */
-#define MAX_PHYSMEM_BITS BITS_PER_LONG
-#endif
-#endif
-#define _PFN_BITS		(MAX_PHYSMEM_BITS - PAGE_SHIFT)
-#define OBJ_INDEX_BITS	(BITS_PER_LONG - _PFN_BITS)
-#define OBJ_INDEX_MASK	((_AC(1, UL) << OBJ_INDEX_BITS) - 1)
-
-#define MAX(a, b) ((a) >= (b) ? (a) : (b))
-/* ZS_MIN_ALLOC_SIZE must be multiple of ZS_ALIGN */
-#define ZS_MIN_ALLOC_SIZE \
-	MAX(32, (ZS_MAX_PAGES_PER_ZSPAGE << PAGE_SHIFT >> OBJ_INDEX_BITS))
-#define ZS_MAX_ALLOC_SIZE	PAGE_SIZE
-
-/*
- * On systems with 4K page size, this gives 254 size classes! There is a
- * trader-off here:
- *  - Large number of size classes is potentially wasteful as free page are
- *    spread across these classes
- *  - Small number of size classes causes large internal fragmentation
- *  - Probably its better to use specific size classes (empirically
- *    determined). NOTE: all those class sizes must be set as multiple of
- *    ZS_ALIGN to make sure link_free itself never has to span 2 pages.
- *
- *  ZS_MIN_ALLOC_SIZE and ZS_SIZE_CLASS_DELTA must be multiple of ZS_ALIGN
- *  (reason above)
- */
-#define ZS_SIZE_CLASS_DELTA	(PAGE_SIZE >> 8)
-#define ZS_SIZE_CLASSES		((ZS_MAX_ALLOC_SIZE - ZS_MIN_ALLOC_SIZE) / \
-					ZS_SIZE_CLASS_DELTA + 1)
-
-/*
- * We do not maintain any list for completely empty or full pages
- */
-enum fullness_group {
-	ZS_ALMOST_FULL,
-	ZS_ALMOST_EMPTY,
-	_ZS_NR_FULLNESS_GROUPS,
-
-	ZS_EMPTY,
-	ZS_FULL
-};
-
-/*
- * We assign a page to ZS_ALMOST_EMPTY fullness group when:
- *	n <= N / f, where
- * n = number of allocated objects
- * N = total number of objects zspage can store
- * f = 1/fullness_threshold_frac
- *
- * Similarly, we assign zspage to:
- *	ZS_ALMOST_FULL	when n > N / f
- *	ZS_EMPTY	when n == 0
- *	ZS_FULL		when n == N
- *
- * (see: fix_fullness_group())
- */
-static const int fullness_threshold_frac = 4;
-
-struct size_class {
-	/*
-	 * Size of objects stored in this class. Must be multiple
-	 * of ZS_ALIGN.
-	 */
-	int size;
-	unsigned int index;
-
-	/* Number of PAGE_SIZE sized pages to combine to form a 'zspage' */
-	int pages_per_zspage;
-
-	spinlock_t lock;
-
-	/* stats */
-	u64 pages_allocated;
-
-	struct page *fullness_list[_ZS_NR_FULLNESS_GROUPS];
-};
-
-/*
- * Placed within free objects to form a singly linked list.
- * For every zspage, first_page->freelist gives head of this list.
- *
- * This must be power of 2 and less than or equal to ZS_ALIGN
- */
-struct link_free {
-	/* Handle of next free chunk (encodes <PFN, obj_idx>) */
-	void *next;
-};
-
-struct zs_pool {
-	struct size_class size_class[ZS_SIZE_CLASSES];
-
-	gfp_t flags;	/* allocation flags used when growing pool */
-};
-
-/*
- * A zspage's class index and fullness group
- * are encoded in its (first)page->mapping
- */
-#define CLASS_IDX_BITS	28
-#define FULLNESS_BITS	4
-#define CLASS_IDX_MASK	((1 << CLASS_IDX_BITS) - 1)
-#define FULLNESS_MASK	((1 << FULLNESS_BITS) - 1)
-
-/*
- * By default, zsmalloc uses a copy-based object mapping method to access
- * allocations that span two pages. However, if a particular architecture
- * performs VM mapping faster than copying, then it should be added here
- * so that USE_PGTABLE_MAPPING is defined. This causes zsmalloc to use
- * page table mapping rather than copying for object mapping.
-*/
-#if defined(CONFIG_ARM) && !defined(MODULE)
-#define USE_PGTABLE_MAPPING
-#endif
-
-struct mapping_area {
-#ifdef USE_PGTABLE_MAPPING
-	struct vm_struct *vm; /* vm area for mapping object that span pages */
-#else
-	char *vm_buf; /* copy buffer for objects that span pages */
-#endif
-	char *vm_addr; /* address of kmap_atomic()'ed pages */
-	enum zs_mapmode vm_mm; /* mapping mode */
-};
-
-
-/* per-cpu VM mapping areas for zspage accesses that cross page boundaries */
-static DEFINE_PER_CPU(struct mapping_area, zs_map_area);
-
-static int is_first_page(struct page *page)
-{
-	return PagePrivate(page);
-}
-
-static int is_last_page(struct page *page)
-{
-	return PagePrivate2(page);
-}
-
-static void get_zspage_mapping(struct page *page, unsigned int *class_idx,
-				enum fullness_group *fullness)
-{
-	unsigned long m;
-	BUG_ON(!is_first_page(page));
-
-	m = (unsigned long)page->mapping;
-	*fullness = m & FULLNESS_MASK;
-	*class_idx = (m >> FULLNESS_BITS) & CLASS_IDX_MASK;
-}
-
-static void set_zspage_mapping(struct page *page, unsigned int class_idx,
-				enum fullness_group fullness)
-{
-	unsigned long m;
-	BUG_ON(!is_first_page(page));
-
-	m = ((class_idx & CLASS_IDX_MASK) << FULLNESS_BITS) |
-			(fullness & FULLNESS_MASK);
-	page->mapping = (struct address_space *)m;
-}
-
-static int get_size_class_index(int size)
-{
-	int idx = 0;
-
-	if (likely(size > ZS_MIN_ALLOC_SIZE))
-		idx = DIV_ROUND_UP(size - ZS_MIN_ALLOC_SIZE,
-				ZS_SIZE_CLASS_DELTA);
-
-	return idx;
-}
-
-static enum fullness_group get_fullness_group(struct page *page)
-{
-	int inuse, max_objects;
-	enum fullness_group fg;
-	BUG_ON(!is_first_page(page));
-
-	inuse = page->inuse;
-	max_objects = page->objects;
-
-	if (inuse == 0)
-		fg = ZS_EMPTY;
-	else if (inuse == max_objects)
-		fg = ZS_FULL;
-	else if (inuse <= max_objects / fullness_threshold_frac)
-		fg = ZS_ALMOST_EMPTY;
-	else
-		fg = ZS_ALMOST_FULL;
-
-	return fg;
-}
-
-static void insert_zspage(struct page *page, struct size_class *class,
-				enum fullness_group fullness)
-{
-	struct page **head;
-
-	BUG_ON(!is_first_page(page));
-
-	if (fullness >= _ZS_NR_FULLNESS_GROUPS)
-		return;
-
-	head = &class->fullness_list[fullness];
-	if (*head)
-		list_add_tail(&page->lru, &(*head)->lru);
-
-	*head = page;
-}
-
-static void remove_zspage(struct page *page, struct size_class *class,
-				enum fullness_group fullness)
-{
-	struct page **head;
-
-	BUG_ON(!is_first_page(page));
-
-	if (fullness >= _ZS_NR_FULLNESS_GROUPS)
-		return;
-
-	head = &class->fullness_list[fullness];
-	BUG_ON(!*head);
-	if (list_empty(&(*head)->lru))
-		*head = NULL;
-	else if (*head == page)
-		*head = (struct page *)list_entry((*head)->lru.next,
-					struct page, lru);
-
-	list_del_init(&page->lru);
-}
-
-static enum fullness_group fix_fullness_group(struct zs_pool *pool,
-						struct page *page)
-{
-	int class_idx;
-	struct size_class *class;
-	enum fullness_group currfg, newfg;
-
-	BUG_ON(!is_first_page(page));
-
-	get_zspage_mapping(page, &class_idx, &currfg);
-	newfg = get_fullness_group(page);
-	if (newfg == currfg)
-		goto out;
-
-	class = &pool->size_class[class_idx];
-	remove_zspage(page, class, currfg);
-	insert_zspage(page, class, newfg);
-	set_zspage_mapping(page, class_idx, newfg);
-
-out:
-	return newfg;
-}
-
-/*
- * We have to decide on how many pages to link together
- * to form a zspage for each size class. This is important
- * to reduce wastage due to unusable space left at end of
- * each zspage which is given as:
- *	wastage = Zp - Zp % size_class
- * where Zp = zspage size = k * PAGE_SIZE where k = 1, 2, ...
- *
- * For example, for size class of 3/8 * PAGE_SIZE, we should
- * link together 3 PAGE_SIZE sized pages to form a zspage
- * since then we can perfectly fit in 8 such objects.
- */
-static int get_pages_per_zspage(int class_size)
-{
-	int i, max_usedpc = 0;
-	/* zspage order which gives maximum used size per KB */
-	int max_usedpc_order = 1;
-
-	for (i = 1; i <= ZS_MAX_PAGES_PER_ZSPAGE; i++) {
-		int zspage_size;
-		int waste, usedpc;
-
-		zspage_size = i * PAGE_SIZE;
-		waste = zspage_size % class_size;
-		usedpc = (zspage_size - waste) * 100 / zspage_size;
-
-		if (usedpc > max_usedpc) {
-			max_usedpc = usedpc;
-			max_usedpc_order = i;
-		}
-	}
-
-	return max_usedpc_order;
-}
-
-/*
- * A single 'zspage' is composed of many system pages which are
- * linked together using fields in struct page. This function finds
- * the first/head page, given any component page of a zspage.
- */
-static struct page *get_first_page(struct page *page)
-{
-	if (is_first_page(page))
-		return page;
-	else
-		return page->first_page;
-}
-
-static struct page *get_next_page(struct page *page)
-{
-	struct page *next;
-
-	if (is_last_page(page))
-		next = NULL;
-	else if (is_first_page(page))
-		next = (struct page *)page->private;
-	else
-		next = list_entry(page->lru.next, struct page, lru);
-
-	return next;
-}
-
-/*
- * Encode <page, obj_idx> as a single handle value.
- * On hardware platforms with physical memory starting at 0x0 the pfn
- * could be 0 so we ensure that the handle will never be 0 by adjusting the
- * encoded obj_idx value before encoding.
- */
-static void *obj_location_to_handle(struct page *page, unsigned long obj_idx)
-{
-	unsigned long handle;
-
-	if (!page) {
-		BUG_ON(obj_idx);
-		return NULL;
-	}
-
-	handle = page_to_pfn(page) << OBJ_INDEX_BITS;
-	handle |= ((obj_idx + 1) & OBJ_INDEX_MASK);
-
-	return (void *)handle;
-}
-
-/*
- * Decode <page, obj_idx> pair from the given object handle. We adjust the
- * decoded obj_idx back to its original value since it was adjusted in
- * obj_location_to_handle().
- */
-static void obj_handle_to_location(unsigned long handle, struct page **page,
-				unsigned long *obj_idx)
-{
-	*page = pfn_to_page(handle >> OBJ_INDEX_BITS);
-	*obj_idx = (handle & OBJ_INDEX_MASK) - 1;
-}
-
-static unsigned long obj_idx_to_offset(struct page *page,
-				unsigned long obj_idx, int class_size)
-{
-	unsigned long off = 0;
-
-	if (!is_first_page(page))
-		off = page->index;
-
-	return off + obj_idx * class_size;
-}
-
-static void reset_page(struct page *page)
-{
-	clear_bit(PG_private, &page->flags);
-	clear_bit(PG_private_2, &page->flags);
-	set_page_private(page, 0);
-	page->mapping = NULL;
-	page->freelist = NULL;
-	page_mapcount_reset(page);
-}
-
-static void free_zspage(struct page *first_page)
-{
-	struct page *nextp, *tmp, *head_extra;
-
-	BUG_ON(!is_first_page(first_page));
-	BUG_ON(first_page->inuse);
-
-	head_extra = (struct page *)page_private(first_page);
-
-	reset_page(first_page);
-	__free_page(first_page);
-
-	/* zspage with only 1 system page */
-	if (!head_extra)
-		return;
-
-	list_for_each_entry_safe(nextp, tmp, &head_extra->lru, lru) {
-		list_del(&nextp->lru);
-		reset_page(nextp);
-		__free_page(nextp);
-	}
-	reset_page(head_extra);
-	__free_page(head_extra);
-}
-
-/* Initialize a newly allocated zspage */
-static void init_zspage(struct page *first_page, struct size_class *class)
-{
-	unsigned long off = 0;
-	struct page *page = first_page;
-
-	BUG_ON(!is_first_page(first_page));
-	while (page) {
-		struct page *next_page;
-		struct link_free *link;
-		unsigned int i, objs_on_page;
-
-		/*
-		 * page->index stores offset of first object starting
-		 * in the page. For the first page, this is always 0,
-		 * so we use first_page->index (aka ->freelist) to store
-		 * head of corresponding zspage's freelist.
-		 */
-		if (page != first_page)
-			page->index = off;
-
-		link = (struct link_free *)kmap_atomic(page) +
-						off / sizeof(*link);
-		objs_on_page = (PAGE_SIZE - off) / class->size;
-
-		for (i = 1; i <= objs_on_page; i++) {
-			off += class->size;
-			if (off < PAGE_SIZE) {
-				link->next = obj_location_to_handle(page, i);
-				link += class->size / sizeof(*link);
-			}
-		}
-
-		/*
-		 * We now come to the last (full or partial) object on this
-		 * page, which must point to the first object on the next
-		 * page (if present)
-		 */
-		next_page = get_next_page(page);
-		link->next = obj_location_to_handle(next_page, 0);
-		kunmap_atomic(link);
-		page = next_page;
-		off = (off + class->size) % PAGE_SIZE;
-	}
-}
-
-/*
- * Allocate a zspage for the given size class
- */
-static struct page *alloc_zspage(struct size_class *class, gfp_t flags)
-{
-	int i, error;
-	struct page *first_page = NULL, *uninitialized_var(prev_page);
-
-	/*
-	 * Allocate individual pages and link them together as:
-	 * 1. first page->private = first sub-page
-	 * 2. all sub-pages are linked together using page->lru
-	 * 3. each sub-page is linked to the first page using page->first_page
-	 *
-	 * For each size class, First/Head pages are linked together using
-	 * page->lru. Also, we set PG_private to identify the first page
-	 * (i.e. no other sub-page has this flag set) and PG_private_2 to
-	 * identify the last page.
-	 */
-	error = -ENOMEM;
-	for (i = 0; i < class->pages_per_zspage; i++) {
-		struct page *page;
-
-		page = alloc_page(flags);
-		if (!page)
-			goto cleanup;
-
-		INIT_LIST_HEAD(&page->lru);
-		if (i == 0) {	/* first page */
-			SetPagePrivate(page);
-			set_page_private(page, 0);
-			first_page = page;
-			first_page->inuse = 0;
-		}
-		if (i == 1)
-			first_page->private = (unsigned long)page;
-		if (i >= 1)
-			page->first_page = first_page;
-		if (i >= 2)
-			list_add(&page->lru, &prev_page->lru);
-		if (i == class->pages_per_zspage - 1)	/* last page */
-			SetPagePrivate2(page);
-		prev_page = page;
-	}
-
-	init_zspage(first_page, class);
-
-	first_page->freelist = obj_location_to_handle(first_page, 0);
-	/* Maximum number of objects we can store in this zspage */
-	first_page->objects = class->pages_per_zspage * PAGE_SIZE / class->size;
-
-	error = 0; /* Success */
-
-cleanup:
-	if (unlikely(error) && first_page) {
-		free_zspage(first_page);
-		first_page = NULL;
-	}
-
-	return first_page;
-}
-
-static struct page *find_get_zspage(struct size_class *class)
-{
-	int i;
-	struct page *page;
-
-	for (i = 0; i < _ZS_NR_FULLNESS_GROUPS; i++) {
-		page = class->fullness_list[i];
-		if (page)
-			break;
-	}
-
-	return page;
-}
-
-#ifdef USE_PGTABLE_MAPPING
-static inline int __zs_cpu_up(struct mapping_area *area)
-{
-	/*
-	 * Make sure we don't leak memory if a cpu UP notification
-	 * and zs_init() race and both call zs_cpu_up() on the same cpu
-	 */
-	if (area->vm)
-		return 0;
-	area->vm = alloc_vm_area(PAGE_SIZE * 2, NULL);
-	if (!area->vm)
-		return -ENOMEM;
-	return 0;
-}
-
-static inline void __zs_cpu_down(struct mapping_area *area)
-{
-	if (area->vm)
-		free_vm_area(area->vm);
-	area->vm = NULL;
-}
-
-static inline void *__zs_map_object(struct mapping_area *area,
-				struct page *pages[2], int off, int size)
-{
-	BUG_ON(map_vm_area(area->vm, PAGE_KERNEL, &pages));
-	area->vm_addr = area->vm->addr;
-	return area->vm_addr + off;
-}
-
-static inline void __zs_unmap_object(struct mapping_area *area,
-				struct page *pages[2], int off, int size)
-{
-	unsigned long addr = (unsigned long)area->vm_addr;
-
-	unmap_kernel_range(addr, PAGE_SIZE * 2);
-}
-
-#else /* USE_PGTABLE_MAPPING */
-
-static inline int __zs_cpu_up(struct mapping_area *area)
-{
-	/*
-	 * Make sure we don't leak memory if a cpu UP notification
-	 * and zs_init() race and both call zs_cpu_up() on the same cpu
-	 */
-	if (area->vm_buf)
-		return 0;
-	area->vm_buf = (char *)__get_free_page(GFP_KERNEL);
-	if (!area->vm_buf)
-		return -ENOMEM;
-	return 0;
-}
-
-static inline void __zs_cpu_down(struct mapping_area *area)
-{
-	if (area->vm_buf)
-		free_page((unsigned long)area->vm_buf);
-	area->vm_buf = NULL;
-}
-
-static void *__zs_map_object(struct mapping_area *area,
-			struct page *pages[2], int off, int size)
-{
-	int sizes[2];
-	void *addr;
-	char *buf = area->vm_buf;
-
-	/* disable page faults to match kmap_atomic() return conditions */
-	pagefault_disable();
-
-	/* no read fastpath */
-	if (area->vm_mm == ZS_MM_WO)
-		goto out;
-
-	sizes[0] = PAGE_SIZE - off;
-	sizes[1] = size - sizes[0];
-
-	/* copy object to per-cpu buffer */
-	addr = kmap_atomic(pages[0]);
-	memcpy(buf, addr + off, sizes[0]);
-	kunmap_atomic(addr);
-	addr = kmap_atomic(pages[1]);
-	memcpy(buf + sizes[0], addr, sizes[1]);
-	kunmap_atomic(addr);
-out:
-	return area->vm_buf;
-}
-
-static void __zs_unmap_object(struct mapping_area *area,
-			struct page *pages[2], int off, int size)
-{
-	int sizes[2];
-	void *addr;
-	char *buf = area->vm_buf;
-
-	/* no write fastpath */
-	if (area->vm_mm == ZS_MM_RO)
-		goto out;
-
-	sizes[0] = PAGE_SIZE - off;
-	sizes[1] = size - sizes[0];
-
-	/* copy per-cpu buffer to object */
-	addr = kmap_atomic(pages[0]);
-	memcpy(addr + off, buf, sizes[0]);
-	kunmap_atomic(addr);
-	addr = kmap_atomic(pages[1]);
-	memcpy(addr, buf + sizes[0], sizes[1]);
-	kunmap_atomic(addr);
-
-out:
-	/* enable page faults to match kunmap_atomic() return conditions */
-	pagefault_enable();
-}
-
-#endif /* USE_PGTABLE_MAPPING */
-
-static int zs_cpu_notifier(struct notifier_block *nb, unsigned long action,
-				void *pcpu)
-{
-	int ret, cpu = (long)pcpu;
-	struct mapping_area *area;
-
-	switch (action) {
-	case CPU_UP_PREPARE:
-		area = &per_cpu(zs_map_area, cpu);
-		ret = __zs_cpu_up(area);
-		if (ret)
-			return notifier_from_errno(ret);
-		break;
-	case CPU_DEAD:
-	case CPU_UP_CANCELED:
-		area = &per_cpu(zs_map_area, cpu);
-		__zs_cpu_down(area);
-		break;
-	}
-
-	return NOTIFY_OK;
-}
-
-static struct notifier_block zs_cpu_nb = {
-	.notifier_call = zs_cpu_notifier
-};
-
-static void zs_exit(void)
-{
-	int cpu;
-
-	for_each_online_cpu(cpu)
-		zs_cpu_notifier(NULL, CPU_DEAD, (void *)(long)cpu);
-	unregister_cpu_notifier(&zs_cpu_nb);
-}
-
-static int zs_init(void)
-{
-	int cpu, ret;
-
-	register_cpu_notifier(&zs_cpu_nb);
-	for_each_online_cpu(cpu) {
-		ret = zs_cpu_notifier(NULL, CPU_UP_PREPARE, (void *)(long)cpu);
-		if (notifier_to_errno(ret))
-			goto fail;
-	}
-	return 0;
-fail:
-	zs_exit();
-	return notifier_to_errno(ret);
-}
-
-/**
- * zs_create_pool - Creates an allocation pool to work from.
- * @flags: allocation flags used to allocate pool metadata
- *
- * This function must be called before anything when using
- * the zsmalloc allocator.
- *
- * On success, a pointer to the newly created pool is returned,
- * otherwise NULL.
- */
-struct zs_pool *zs_create_pool(gfp_t flags)
-{
-	int i, ovhd_size;
-	struct zs_pool *pool;
-
-	ovhd_size = roundup(sizeof(*pool), PAGE_SIZE);
-	pool = kzalloc(ovhd_size, GFP_KERNEL);
-	if (!pool)
-		return NULL;
-
-	for (i = 0; i < ZS_SIZE_CLASSES; i++) {
-		int size;
-		struct size_class *class;
-
-		size = ZS_MIN_ALLOC_SIZE + i * ZS_SIZE_CLASS_DELTA;
-		if (size > ZS_MAX_ALLOC_SIZE)
-			size = ZS_MAX_ALLOC_SIZE;
-
-		class = &pool->size_class[i];
-		class->size = size;
-		class->index = i;
-		spin_lock_init(&class->lock);
-		class->pages_per_zspage = get_pages_per_zspage(size);
-
-	}
-
-	pool->flags = flags;
-
-	return pool;
-}
-EXPORT_SYMBOL_GPL(zs_create_pool);
-
-void zs_destroy_pool(struct zs_pool *pool)
-{
-	int i;
-
-	for (i = 0; i < ZS_SIZE_CLASSES; i++) {
-		int fg;
-		struct size_class *class = &pool->size_class[i];
-
-		for (fg = 0; fg < _ZS_NR_FULLNESS_GROUPS; fg++) {
-			if (class->fullness_list[fg]) {
-				pr_info("Freeing non-empty class with size "
-					"%db, fullness group %d\n",
-					class->size, fg);
-			}
-		}
-	}
-	kfree(pool);
-}
-EXPORT_SYMBOL_GPL(zs_destroy_pool);
-
-/**
- * zs_malloc - Allocate block of given size from pool.
- * @pool: pool to allocate from
- * @size: size of block to allocate
- *
- * On success, handle to the allocated object is returned,
- * otherwise 0.
- * Allocation requests with size > ZS_MAX_ALLOC_SIZE will fail.
- */
-unsigned long zs_malloc(struct zs_pool *pool, size_t size)
-{
-	unsigned long obj;
-	struct link_free *link;
-	int class_idx;
-	struct size_class *class;
-
-	struct page *first_page, *m_page;
-	unsigned long m_objidx, m_offset;
-
-	if (unlikely(!size || size > ZS_MAX_ALLOC_SIZE))
-		return 0;
-
-	class_idx = get_size_class_index(size);
-	class = &pool->size_class[class_idx];
-	BUG_ON(class_idx != class->index);
-
-	spin_lock(&class->lock);
-	first_page = find_get_zspage(class);
-
-	if (!first_page) {
-		spin_unlock(&class->lock);
-		first_page = alloc_zspage(class, pool->flags);
-		if (unlikely(!first_page))
-			return 0;
-
-		set_zspage_mapping(first_page, class->index, ZS_EMPTY);
-		spin_lock(&class->lock);
-		class->pages_allocated += class->pages_per_zspage;
-	}
-
-	obj = (unsigned long)first_page->freelist;
-	obj_handle_to_location(obj, &m_page, &m_objidx);
-	m_offset = obj_idx_to_offset(m_page, m_objidx, class->size);
-
-	link = (struct link_free *)kmap_atomic(m_page) +
-					m_offset / sizeof(*link);
-	first_page->freelist = link->next;
-	memset(link, POISON_INUSE, sizeof(*link));
-	kunmap_atomic(link);
-
-	first_page->inuse++;
-	/* Now move the zspage to another fullness group, if required */
-	fix_fullness_group(pool, first_page);
-	spin_unlock(&class->lock);
-
-	return obj;
-}
-EXPORT_SYMBOL_GPL(zs_malloc);
-
-void zs_free(struct zs_pool *pool, unsigned long obj)
-{
-	struct link_free *link;
-	struct page *first_page, *f_page;
-	unsigned long f_objidx, f_offset;
-
-	int class_idx;
-	struct size_class *class;
-	enum fullness_group fullness;
-
-	if (unlikely(!obj))
-		return;
-
-	obj_handle_to_location(obj, &f_page, &f_objidx);
-	first_page = get_first_page(f_page);
-
-	get_zspage_mapping(first_page, &class_idx, &fullness);
-	class = &pool->size_class[class_idx];
-	f_offset = obj_idx_to_offset(f_page, f_objidx, class->size);
-
-	spin_lock(&class->lock);
-
-	/* Insert this object in containing zspage's freelist */
-	link = (struct link_free *)((unsigned char *)kmap_atomic(f_page)
-							+ f_offset);
-	link->next = first_page->freelist;
-	kunmap_atomic(link);
-	first_page->freelist = (void *)obj;
-
-	first_page->inuse--;
-	fullness = fix_fullness_group(pool, first_page);
-
-	if (fullness == ZS_EMPTY)
-		class->pages_allocated -= class->pages_per_zspage;
-
-	spin_unlock(&class->lock);
-
-	if (fullness == ZS_EMPTY)
-		free_zspage(first_page);
-}
-EXPORT_SYMBOL_GPL(zs_free);
-
-/**
- * zs_map_object - get address of allocated object from handle.
- * @pool: pool from which the object was allocated
- * @handle: handle returned from zs_malloc
- *
- * Before using an object allocated from zs_malloc, it must be mapped using
- * this function. When done with the object, it must be unmapped using
- * zs_unmap_object.
- *
- * Only one object can be mapped per cpu at a time. There is no protection
- * against nested mappings.
- *
- * This function returns with preemption and page faults disabled.
-*/
-void *zs_map_object(struct zs_pool *pool, unsigned long handle,
-			enum zs_mapmode mm)
-{
-	struct page *page;
-	unsigned long obj_idx, off;
-
-	unsigned int class_idx;
-	enum fullness_group fg;
-	struct size_class *class;
-	struct mapping_area *area;
-	struct page *pages[2];
-
-	BUG_ON(!handle);
-
-	/*
-	 * Because we use per-cpu mapping areas shared among the
-	 * pools/users, we can't allow mapping in interrupt context
-	 * because it can corrupt another users mappings.
-	 */
-	BUG_ON(in_interrupt());
-
-	obj_handle_to_location(handle, &page, &obj_idx);
-	get_zspage_mapping(get_first_page(page), &class_idx, &fg);
-	class = &pool->size_class[class_idx];
-	off = obj_idx_to_offset(page, obj_idx, class->size);
-
-	area = &get_cpu_var(zs_map_area);
-	area->vm_mm = mm;
-	if (off + class->size <= PAGE_SIZE) {
-		/* this object is contained entirely within a page */
-		area->vm_addr = kmap_atomic(page);
-		return area->vm_addr + off;
-	}
-
-	/* this object spans two pages */
-	pages[0] = page;
-	pages[1] = get_next_page(page);
-	BUG_ON(!pages[1]);
-
-	return __zs_map_object(area, pages, off, class->size);
-}
-EXPORT_SYMBOL_GPL(zs_map_object);
-
-void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
-{
-	struct page *page;
-	unsigned long obj_idx, off;
-
-	unsigned int class_idx;
-	enum fullness_group fg;
-	struct size_class *class;
-	struct mapping_area *area;
-
-	BUG_ON(!handle);
-
-	obj_handle_to_location(handle, &page, &obj_idx);
-	get_zspage_mapping(get_first_page(page), &class_idx, &fg);
-	class = &pool->size_class[class_idx];
-	off = obj_idx_to_offset(page, obj_idx, class->size);
-
-	area = &__get_cpu_var(zs_map_area);
-	if (off + class->size <= PAGE_SIZE)
-		kunmap_atomic(area->vm_addr);
-	else {
-		struct page *pages[2];
-
-		pages[0] = page;
-		pages[1] = get_next_page(page);
-		BUG_ON(!pages[1]);
-
-		__zs_unmap_object(area, pages, off, class->size);
-	}
-	put_cpu_var(zs_map_area);
-}
-EXPORT_SYMBOL_GPL(zs_unmap_object);
-
-u64 zs_get_total_size_bytes(struct zs_pool *pool)
-{
-	int i;
-	u64 npages = 0;
-
-	for (i = 0; i < ZS_SIZE_CLASSES; i++)
-		npages += pool->size_class[i].pages_allocated;
-
-	return npages << PAGE_SHIFT;
-}
-EXPORT_SYMBOL_GPL(zs_get_total_size_bytes);
-
-module_init(zs_init);
-module_exit(zs_exit);
-
-MODULE_LICENSE("Dual BSD/GPL");
-MODULE_AUTHOR("Nitin Gupta <ngupta@vflare.org>");
diff --git a/drivers/staging/zsmalloc/zsmalloc.h b/drivers/staging/zsmalloc/zsmalloc.h
deleted file mode 100644
index 46dbd0558d86..000000000000
--- a/drivers/staging/zsmalloc/zsmalloc.h
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
- * zsmalloc memory allocator
- *
- * Copyright (C) 2011  Nitin Gupta
- *
- * This code is released using a dual license strategy: BSD/GPL
- * You can choose the license 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 _ZS_MALLOC_H_
-#define _ZS_MALLOC_H_
-
-#include <linux/types.h>
-
-/*
- * zsmalloc mapping modes
- *
- * NOTE: These only make a difference when a mapped object spans pages
-*/
-enum zs_mapmode {
-	ZS_MM_RW, /* normal read-write mapping */
-	ZS_MM_RO, /* read-only (no copy-out at unmap time) */
-	ZS_MM_WO /* write-only (no copy-in at map time) */
-};
-
-struct zs_pool;
-
-struct zs_pool *zs_create_pool(gfp_t flags);
-void zs_destroy_pool(struct zs_pool *pool);
-
-unsigned long zs_malloc(struct zs_pool *pool, size_t size);
-void zs_free(struct zs_pool *pool, unsigned long obj);
-
-void *zs_map_object(struct zs_pool *pool, unsigned long handle,
-			enum zs_mapmode mm);
-void zs_unmap_object(struct zs_pool *pool, unsigned long handle);
-
-u64 zs_get_total_size_bytes(struct zs_pool *pool);
-
-#endif