1 files changed, 0 insertions, 760 deletions

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");