Merge branch 'akpm' (patches from Andrew Morton)

Merge misc fixes from Andrew Morton:
 "A few hotfixes and various leftovers which were awaiting other merges.

  Mainly movement of zram into mm/"

* emailed patches fron Andrew Morton <akpm@linux-foundation.org>: (25 commits)
  memcg: fix mutex not unlocked on memcg_create_kmem_cache fail path
  Documentation/filesystems/vfs.txt: update file_operations documentation
  mm, oom: base root bonus on current usage
  mm: don't lose the SOFT_DIRTY flag on mprotect
  mm/slub.c: fix page->_count corruption (again)
  mm/mempolicy.c: fix mempolicy printing in numa_maps
  zram: remove zram->lock in read path and change it with mutex
  zram: remove workqueue for freeing removed pending slot
  zram: introduce zram->tb_lock
  zram: use atomic operation for stat
  zram: remove unnecessary free
  zram: delay pending free request in read path
  zram: fix race between reset and flushing pending work
  zsmalloc: add maintainers
  zram: add zram maintainers
  zsmalloc: add copyright
  zram: add copyright
  zram: remove old private project comment
  zram: promote zram from staging
  zsmalloc: move it under mm
  ...

15 files changed, 59 insertions, 1374 deletions

diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
index 9ffa90c6201c..014a1cfc41c5 100644
--- a/drivers/block/Kconfig
+++ b/drivers/block/Kconfig
@@ -108,6 +108,8 @@ 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 && 0
diff --git a/drivers/block/Makefile b/drivers/block/Makefile
index 816d979c3266..02b688d1438d 100644
--- a/drivers/block/Makefile
+++ b/drivers/block/Makefile
@@ -42,6 +42,7 @@ obj-$(CONFIG_BLK_DEV_PCIESSD_MTIP32XX)	+= mtip32xx/
 
 obj-$(CONFIG_BLK_DEV_RSXX) += rsxx/
 obj-$(CONFIG_BLK_DEV_NULL_BLK)	+= null_blk.o
+obj-$(CONFIG_ZRAM) += zram/
 
 nvme-y		:= nvme-core.o nvme-scsi.o
 skd-y		:= skd_main.o
diff --git a/drivers/staging/zram/Kconfig b/drivers/block/zram/Kconfig
index 983314c41349..3450be850399 100644
--- a/drivers/staging/zram/Kconfig
+++ b/drivers/block/zram/Kconfig
@@ -14,7 +14,6 @@ config ZRAM
 	  disks and maybe many more.
 
 	  See zram.txt for more information.
-	  Project home: <https://compcache.googlecode.com/>
 
 config ZRAM_DEBUG
 	bool "Compressed RAM block device debug support"
diff --git a/drivers/staging/zram/Makefile b/drivers/block/zram/Makefile
index cb0f9ced6a93..cb0f9ced6a93 100644
--- a/drivers/staging/zram/Makefile
+++ b/drivers/block/zram/Makefile
diff --git a/drivers/staging/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 108f2733106d..011e55d820b1 100644
--- a/drivers/staging/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -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.
@@ -9,7 +10,6 @@
  * 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"
@@ -104,7 +104,7 @@ static ssize_t zero_pages_show(struct device *dev,
 {
 	struct zram *zram = dev_to_zram(dev);
 
-	return sprintf(buf, "%u\n", zram->stats.pages_zero);
+	return sprintf(buf, "%u\n", atomic_read(&zram->stats.pages_zero));
 }
 
 static ssize_t orig_data_size_show(struct device *dev,
@@ -113,7 +113,7 @@ static ssize_t orig_data_size_show(struct device *dev,
 	struct zram *zram = dev_to_zram(dev);
 
 	return sprintf(buf, "%llu\n",
-		(u64)(zram->stats.pages_stored) << PAGE_SHIFT);
+		(u64)(atomic_read(&zram->stats.pages_stored)) << PAGE_SHIFT);
 }
 
 static ssize_t compr_data_size_show(struct device *dev,
@@ -140,6 +140,7 @@ static ssize_t mem_used_total_show(struct device *dev,
 	return sprintf(buf, "%llu\n", val);
 }
 
+/* flag operations needs meta->tb_lock */
 static int zram_test_flag(struct zram_meta *meta, u32 index,
 			enum zram_pageflags flag)
 {
@@ -228,6 +229,8 @@ static struct zram_meta *zram_meta_alloc(u64 disksize)
 		goto free_table;
 	}
 
+	rwlock_init(&meta->tb_lock);
+	mutex_init(&meta->buffer_lock);
 	return meta;
 
 free_table:
@@ -280,6 +283,7 @@ static void handle_zero_page(struct bio_vec *bvec)
 	flush_dcache_page(page);
 }
 
+/* NOTE: caller should hold meta->tb_lock with write-side */
 static void zram_free_page(struct zram *zram, size_t index)
 {
 	struct zram_meta *meta = zram->meta;
@@ -293,21 +297,21 @@ static void zram_free_page(struct zram *zram, size_t index)
 		 */
 		if (zram_test_flag(meta, index, ZRAM_ZERO)) {
 			zram_clear_flag(meta, index, ZRAM_ZERO);
-			zram->stats.pages_zero--;
+			atomic_dec(&zram->stats.pages_zero);
 		}
 		return;
 	}
 
 	if (unlikely(size > max_zpage_size))
-		zram->stats.bad_compress--;
+		atomic_dec(&zram->stats.bad_compress);
 
 	zs_free(meta->mem_pool, handle);
 
 	if (size <= PAGE_SIZE / 2)
-		zram->stats.good_compress--;
+		atomic_dec(&zram->stats.good_compress);
 
 	atomic64_sub(meta->table[index].size, &zram->stats.compr_size);
-	zram->stats.pages_stored--;
+	atomic_dec(&zram->stats.pages_stored);
 
 	meta->table[index].handle = 0;
 	meta->table[index].size = 0;
@@ -319,20 +323,26 @@ static int zram_decompress_page(struct zram *zram, char *mem, u32 index)
 	size_t clen = PAGE_SIZE;
 	unsigned char *cmem;
 	struct zram_meta *meta = zram->meta;
-	unsigned long handle = meta->table[index].handle;
+	unsigned long handle;
+	u16 size;
+
+	read_lock(&meta->tb_lock);
+	handle = meta->table[index].handle;
+	size = meta->table[index].size;
 
 	if (!handle || zram_test_flag(meta, index, ZRAM_ZERO)) {
+		read_unlock(&meta->tb_lock);
 		clear_page(mem);
 		return 0;
 	}
 
 	cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_RO);
-	if (meta->table[index].size == PAGE_SIZE)
+	if (size == PAGE_SIZE)
 		copy_page(mem, cmem);
 	else
-		ret = lzo1x_decompress_safe(cmem, meta->table[index].size,
-						mem, &clen);
+		ret = lzo1x_decompress_safe(cmem, size,	mem, &clen);
 	zs_unmap_object(meta->mem_pool, handle);
+	read_unlock(&meta->tb_lock);
 
 	/* Should NEVER happen. Return bio error if it does. */
 	if (unlikely(ret != LZO_E_OK)) {
@@ -353,11 +363,14 @@ static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
 	struct zram_meta *meta = zram->meta;
 	page = bvec->bv_page;
 
+	read_lock(&meta->tb_lock);
 	if (unlikely(!meta->table[index].handle) ||
 			zram_test_flag(meta, index, ZRAM_ZERO)) {
+		read_unlock(&meta->tb_lock);
 		handle_zero_page(bvec);
 		return 0;
 	}
+	read_unlock(&meta->tb_lock);
 
 	if (is_partial_io(bvec))
 		/* Use  a temporary buffer to decompress the page */
@@ -400,6 +413,7 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
 	struct page *page;
 	unsigned char *user_mem, *cmem, *src, *uncmem = NULL;
 	struct zram_meta *meta = zram->meta;
+	bool locked = false;
 
 	page = bvec->bv_page;
 	src = meta->compress_buffer;
@@ -419,6 +433,8 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
 			goto out;
 	}
 
+	mutex_lock(&meta->buffer_lock);
+	locked = true;
 	user_mem = kmap_atomic(page);
 
 	if (is_partial_io(bvec)) {
@@ -433,25 +449,18 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
 	if (page_zero_filled(uncmem)) {
 		kunmap_atomic(user_mem);
 		/* Free memory associated with this sector now. */
+		write_lock(&zram->meta->tb_lock);
 		zram_free_page(zram, index);
-
-		zram->stats.pages_zero++;
 		zram_set_flag(meta, index, ZRAM_ZERO);
+		write_unlock(&zram->meta->tb_lock);
+
+		atomic_inc(&zram->stats.pages_zero);
 		ret = 0;
 		goto out;
 	}
 
-	/*
-	 * zram_slot_free_notify could miss free so that let's
-	 * double check.
-	 */
-	if (unlikely(meta->table[index].handle ||
-			zram_test_flag(meta, index, ZRAM_ZERO)))
-		zram_free_page(zram, index);
-
 	ret = lzo1x_1_compress(uncmem, PAGE_SIZE, src, &clen,
 			       meta->compress_workmem);
-
 	if (!is_partial_io(bvec)) {
 		kunmap_atomic(user_mem);
 		user_mem = NULL;
@@ -464,7 +473,7 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
 	}
 
 	if (unlikely(clen > max_zpage_size)) {
-		zram->stats.bad_compress++;
+		atomic_inc(&zram->stats.bad_compress);
 		clen = PAGE_SIZE;
 		src = NULL;
 		if (is_partial_io(bvec))
@@ -494,18 +503,22 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
 	 * Free memory associated with this sector
 	 * before overwriting unused sectors.
 	 */
+	write_lock(&zram->meta->tb_lock);
 	zram_free_page(zram, index);
 
 	meta->table[index].handle = handle;
 	meta->table[index].size = clen;
+	write_unlock(&zram->meta->tb_lock);
 
 	/* Update stats */
 	atomic64_add(clen, &zram->stats.compr_size);
-	zram->stats.pages_stored++;
+	atomic_inc(&zram->stats.pages_stored);
 	if (clen <= PAGE_SIZE / 2)
-		zram->stats.good_compress++;
+		atomic_inc(&zram->stats.good_compress);
 
 out:
+	if (locked)
+		mutex_unlock(&meta->buffer_lock);
 	if (is_partial_io(bvec))
 		kfree(uncmem);
 
@@ -514,36 +527,15 @@ out:
 	return ret;
 }
 
-static void handle_pending_slot_free(struct zram *zram)
-{
-	struct zram_slot_free *free_rq;
-
-	spin_lock(&zram->slot_free_lock);
-	while (zram->slot_free_rq) {
-		free_rq = zram->slot_free_rq;
-		zram->slot_free_rq = free_rq->next;
-		zram_free_page(zram, free_rq->index);
-		kfree(free_rq);
-	}
-	spin_unlock(&zram->slot_free_lock);
-}
-
 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);
-		handle_pending_slot_free(zram);
+	if (rw == READ)
 		ret = zram_bvec_read(zram, bvec, index, offset, bio);
-		up_read(&zram->lock);
-	} else {
-		down_write(&zram->lock);
-		handle_pending_slot_free(zram);
+	else
 		ret = zram_bvec_write(zram, bvec, index, offset);
-		up_write(&zram->lock);
-	}
 
 	return ret;
 }
@@ -553,8 +545,6 @@ static void zram_reset_device(struct zram *zram, bool reset_capacity)
 	size_t index;
 	struct zram_meta *meta;
 
-	flush_work(&zram->free_work);
-
 	down_write(&zram->init_lock);
 	if (!zram->init_done) {
 		up_write(&zram->init_lock);
@@ -762,40 +752,19 @@ error:
 	bio_io_error(bio);
 }
 
-static void zram_slot_free(struct work_struct *work)
-{
-	struct zram *zram;
-
-	zram = container_of(work, struct zram, free_work);
-	down_write(&zram->lock);
-	handle_pending_slot_free(zram);
-	up_write(&zram->lock);
-}
-
-static void add_slot_free(struct zram *zram, struct zram_slot_free *free_rq)
-{
-	spin_lock(&zram->slot_free_lock);
-	free_rq->next = zram->slot_free_rq;
-	zram->slot_free_rq = free_rq;
-	spin_unlock(&zram->slot_free_lock);
-}
-
 static void zram_slot_free_notify(struct block_device *bdev,
 				unsigned long index)
 {
 	struct zram *zram;
-	struct zram_slot_free *free_rq;
+	struct zram_meta *meta;
 
 	zram = bdev->bd_disk->private_data;
-	atomic64_inc(&zram->stats.notify_free);
-
-	free_rq = kmalloc(sizeof(struct zram_slot_free), GFP_ATOMIC);
-	if (!free_rq)
-		return;
+	meta = zram->meta;
 
-	free_rq->index = index;
-	add_slot_free(zram, free_rq);
-	schedule_work(&zram->free_work);
+	write_lock(&meta->tb_lock);
+	zram_free_page(zram, index);
+	write_unlock(&meta->tb_lock);
+	atomic64_inc(&zram->stats.notify_free);
 }
 
 static const struct block_device_operations zram_devops = {
@@ -839,13 +808,8 @@ static int create_device(struct zram *zram, int device_id)
 {
 	int ret = -ENOMEM;
 
-	init_rwsem(&zram->lock);
 	init_rwsem(&zram->init_lock);
 
-	INIT_WORK(&zram->free_work, zram_slot_free);
-	spin_lock_init(&zram->slot_free_lock);
-	zram->slot_free_rq = NULL;
-
 	zram->queue = blk_alloc_queue(GFP_KERNEL);
 	if (!zram->queue) {
 		pr_err("Error allocating disk queue for device %d\n",
diff --git a/drivers/staging/zram/zram_drv.h b/drivers/block/zram/zram_drv.h
index 97a3acf6ab76..ad8aa35bae00 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.
@@ -9,7 +10,6 @@
  * 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_
@@ -17,8 +17,7 @@
 
 #include <linux/spinlock.h>
 #include <linux/mutex.h>
-
-#include "../zsmalloc/zsmalloc.h"
+#include <linux/zsmalloc.h>
 
 /*
  * Some arbitrary value. This is just to catch
@@ -69,10 +68,6 @@ struct table {
 	u8 flags;
 } __aligned(4);
 
-/*
- * All 64bit fields should only be manipulated by 64bit atomic accessors.
- * All modifications to 32bit counter should be protected by zram->lock.
- */
 struct zram_stats {
 	atomic64_t compr_size;	/* compressed size of pages stored */
 	atomic64_t num_reads;	/* failed + successful */
@@ -81,33 +76,23 @@ struct zram_stats {
 	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 */
-	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% */
+	atomic_t pages_zero;		/* no. of zero filled pages */
+	atomic_t pages_stored;	/* no. of pages currently stored */
+	atomic_t good_compress;	/* % of pages with compression ratio<=50% */
+	atomic_t bad_compress;	/* % of pages with compression ratio>=75% */
 };
 
 struct zram_meta {
+	rwlock_t tb_lock;	/* protect table */
 	void *compress_workmem;
 	void *compress_buffer;
 	struct table *table;
 	struct zs_pool *mem_pool;
-};
-
-struct zram_slot_free {
-	unsigned long index;
-	struct zram_slot_free *next;
+	struct mutex buffer_lock; /* protect compress buffers */
 };
 
 struct zram {
 	struct zram_meta *meta;
-	struct rw_semaphore lock; /* protect compression buffers, table,
-				   * 32bit stat counters against concurrent
-				   * notifications, reads and writes */
-
-	struct work_struct free_work;  /* handle pending free request */
-	struct zram_slot_free *slot_free_rq; /* list head of free request */
-
 	struct request_queue *queue;
 	struct gendisk *disk;
 	int init_done;
@@ -118,7 +103,6 @@ struct zram {
 	 * we can store in a disk.
 	 */
 	u64 disksize;	/* bytes */
-	spinlock_t slot_free_lock;
 
 	struct zram_stats stats;
 };
diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index 930694d3a13f..71e49000fbf3 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -150,6 +150,7 @@ int mdiobus_register(struct mii_bus *bus)
 	err = device_register(&bus->dev);
 	if (err) {
 		pr_err("mii_bus %s failed to register\n", bus->id);
+		put_device(&bus->dev);
 		return -EINVAL;
 	}
 
diff --git a/drivers/staging/Kconfig b/drivers/staging/Kconfig
index 4bb6b11166b3..040a51525b42 100644
--- a/drivers/staging/Kconfig
+++ b/drivers/staging/Kconfig
@@ -76,10 +76,6 @@ 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 9f07e5e16094..dea056bf7ff2 100644
--- a/drivers/staging/Makefile
+++ b/drivers/staging/Makefile
@@ -32,8 +32,6 @@ 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/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/zsmalloc/Kconfig b/drivers/staging/zsmalloc/Kconfig
deleted file mode 100644
index 9d1f2a24ad62..000000000000
--- a/drivers/staging/zsmalloc/Kconfig
+++ /dev/null
@@ -1,24 +0,0 @@
-config ZSMALLOC
-	bool "Memory allocator for compressed pages"
-	depends on MMU
-	default n
-	help
-	  zsmalloc is a slab-based memory allocator designed to store
-	  compressed RAM pages.  zsmalloc uses virtual memory mapping
-	  in order to reduce fragmentation.  However, this results in a
-	  non-standard allocator interface where a handle, not a pointer, is
-	  returned by an alloc().  This handle must be mapped in order to
-	  access the allocated space.
-
-config PGTABLE_MAPPING
-	bool "Use page table mapping to access object in zsmalloc"
-	depends on ZSMALLOC
-	help
-	  By default, zsmalloc uses a copy-based object mapping method to
-	  access allocations that span two pages. However, if a particular
-	  architecture (ex, ARM) performs VM mapping faster than copying,
-	  then you should select this. This causes zsmalloc to use page table
-	  mapping rather than copying for object mapping.
-
-	  You can check speed with zsmalloc benchmark[1].
-	  [1] https://github.com/spartacus06/zsmalloc
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 7660c87d8b2a..000000000000
--- a/drivers/staging/zsmalloc/zsmalloc-main.c
+++ /dev/null
@@ -1,1106 +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 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.
- *
- * For simplicity, zsmalloc can only allocate objects of size up to PAGE_SIZE
- * since this satisfies the requirements of all its current users (in the
- * worst case, page is incompressible and is thus stored "as-is" i.e. in
- * uncompressed form). For allocation requests larger than this size, failure
- * is returned (see zs_malloc).
- *
- * Additionally, zs_malloc() does not return a dereferenceable pointer.
- * Instead, it returns an opaque handle (unsigned long) which encodes actual
- * location of the allocated object. The reason for this indirection is that
- * zsmalloc does not keep zspages permanently mapped since that would cause
- * issues on 32-bit systems where the VA region for kernel space mappings
- * is very small. So, before using the allocating memory, the object has to
- * be mapped using zs_map_object() to get a usable pointer and subsequently
- * unmapped using zs_unmap_object().
- *
- * 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/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 (unsigned long) 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)
-
-struct mapping_area {
-#ifdef CONFIG_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;
-}
-
-/*
- * zsmalloc divides the pool into various size classes where each
- * class maintains a list of zspages where each zspage is divided
- * into equal sized chunks. Each allocation falls into one of these
- * classes depending on its size. This function returns index of the
- * size class which has chunk size big enough to hold the give size.
- */
-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;
-}
-
-/*
- * For each size class, zspages are divided into different groups
- * depending on how "full" they are. This was done so that we could
- * easily find empty or nearly empty zspages when we try to shrink
- * the pool (not yet implemented). This function returns fullness
- * status of the given page.
- */
-static enum fullness_group get_fullness_group(struct page *page)
-{
-	int inuse, max_objects;
-	enum fullness_group fg;
-	BUG_ON(!is_first