zram: remove zram_sysfs file (v2)

Move zram sysfs code to zram drv and remove zram_sysfs.c
file. This gives ability to make static a number of previously
exported zram functions, used from zram sysfs, e.g. internal zram
zram_meta_alloc/free(). We also can drop zram_drv wrapper
functions, used from zram sysfs:
e.g. zram_reset_device()/__zram_reset_device() pair.

v2: as suggested by Greg K-H, move MODULE description to the
bottom of the file.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/zram/Makefile

-zram-y	:=	zram_drv.o zram_sysfs.o
+zram-y	:=	zram_drv.o
 
 obj-$(CONFIG_ZRAM)	+=	zram.o

drivers/staging/zram/zram_drv.h

@@ -112,14 +112,4 @@ struct zram {
 
 	struct zram_stats stats;
 };
-
-#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);
-
 #endif

drivers/staging/zram/zram_sysfs.c

-/*
- * 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 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 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",
-			(u64)atomic64_read(&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",
-			(u64)atomic64_read(&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",
-			(u64)atomic64_read(&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",
-			(u64)atomic64_read(&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",
-			(u64)atomic64_read(&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,
-};