Moved, renamed, and deleted files

The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.

1 files changed, 0 insertions, 1038 deletions

diff --git a/ANDROID_3.4.5/fs/btrfs/compression.c b/ANDROID_3.4.5/fs/btrfs/compression.c
deleted file mode 100644
index 86eff48d..00000000
--- a/ANDROID_3.4.5/fs/btrfs/compression.c
+++ /dev/null
@@ -1,1038 +0,0 @@
-/*
- * Copyright (C) 2008 Oracle.  All rights reserved.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public
- * License v2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public
- * License along with this program; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 021110-1307, USA.
- */
-
-#include <linux/kernel.h>
-#include <linux/bio.h>
-#include <linux/buffer_head.h>
-#include <linux/file.h>
-#include <linux/fs.h>
-#include <linux/pagemap.h>
-#include <linux/highmem.h>
-#include <linux/time.h>
-#include <linux/init.h>
-#include <linux/string.h>
-#include <linux/backing-dev.h>
-#include <linux/mpage.h>
-#include <linux/swap.h>
-#include <linux/writeback.h>
-#include <linux/bit_spinlock.h>
-#include <linux/slab.h>
-#include "compat.h"
-#include "ctree.h"
-#include "disk-io.h"
-#include "transaction.h"
-#include "btrfs_inode.h"
-#include "volumes.h"
-#include "ordered-data.h"
-#include "compression.h"
-#include "extent_io.h"
-#include "extent_map.h"
-
-struct compressed_bio {
-	/* number of bios pending for this compressed extent */
-	atomic_t pending_bios;
-
-	/* the pages with the compressed data on them */
-	struct page **compressed_pages;
-
-	/* inode that owns this data */
-	struct inode *inode;
-
-	/* starting offset in the inode for our pages */
-	u64 start;
-
-	/* number of bytes in the inode we're working on */
-	unsigned long len;
-
-	/* number of bytes on disk */
-	unsigned long compressed_len;
-
-	/* the compression algorithm for this bio */
-	int compress_type;
-
-	/* number of compressed pages in the array */
-	unsigned long nr_pages;
-
-	/* IO errors */
-	int errors;
-	int mirror_num;
-
-	/* for reads, this is the bio we are copying the data into */
-	struct bio *orig_bio;
-
-	/*
-	 * the start of a variable length array of checksums only
-	 * used by reads
-	 */
-	u32 sums;
-};
-
-static inline int compressed_bio_size(struct btrfs_root *root,
-				      unsigned long disk_size)
-{
-	u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
-
-	return sizeof(struct compressed_bio) +
-		((disk_size + root->sectorsize - 1) / root->sectorsize) *
-		csum_size;
-}
-
-static struct bio *compressed_bio_alloc(struct block_device *bdev,
-					u64 first_byte, gfp_t gfp_flags)
-{
-	int nr_vecs;
-
-	nr_vecs = bio_get_nr_vecs(bdev);
-	return btrfs_bio_alloc(bdev, first_byte >> 9, nr_vecs, gfp_flags);
-}
-
-static int check_compressed_csum(struct inode *inode,
-				 struct compressed_bio *cb,
-				 u64 disk_start)
-{
-	int ret;
-	struct btrfs_root *root = BTRFS_I(inode)->root;
-	struct page *page;
-	unsigned long i;
-	char *kaddr;
-	u32 csum;
-	u32 *cb_sum = &cb->sums;
-
-	if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
-		return 0;
-
-	for (i = 0; i < cb->nr_pages; i++) {
-		page = cb->compressed_pages[i];
-		csum = ~(u32)0;
-
-		kaddr = kmap_atomic(page);
-		csum = btrfs_csum_data(root, kaddr, csum, PAGE_CACHE_SIZE);
-		btrfs_csum_final(csum, (char *)&csum);
-		kunmap_atomic(kaddr);
-
-		if (csum != *cb_sum) {
-			printk(KERN_INFO "btrfs csum failed ino %llu "
-			       "extent %llu csum %u "
-			       "wanted %u mirror %d\n",
-			       (unsigned long long)btrfs_ino(inode),
-			       (unsigned long long)disk_start,
-			       csum, *cb_sum, cb->mirror_num);
-			ret = -EIO;
-			goto fail;
-		}
-		cb_sum++;
-
-	}
-	ret = 0;
-fail:
-	return ret;
-}
-
-/* when we finish reading compressed pages from the disk, we
- * decompress them and then run the bio end_io routines on the
- * decompressed pages (in the inode address space).
- *
- * This allows the checksumming and other IO error handling routines
- * to work normally
- *
- * The compressed pages are freed here, and it must be run
- * in process context
- */
-static void end_compressed_bio_read(struct bio *bio, int err)
-{
-	struct compressed_bio *cb = bio->bi_private;
-	struct inode *inode;
-	struct page *page;
-	unsigned long index;
-	int ret;
-
-	if (err)
-		cb->errors = 1;
-
-	/* if there are more bios still pending for this compressed
-	 * extent, just exit
-	 */
-	if (!atomic_dec_and_test(&cb->pending_bios))
-		goto out;
-
-	inode = cb->inode;
-	ret = check_compressed_csum(inode, cb, (u64)bio->bi_sector << 9);
-	if (ret)
-		goto csum_failed;
-
-	/* ok, we're the last bio for this extent, lets start
-	 * the decompression.
-	 */
-	ret = btrfs_decompress_biovec(cb->compress_type,
-				      cb->compressed_pages,
-				      cb->start,
-				      cb->orig_bio->bi_io_vec,
-				      cb->orig_bio->bi_vcnt,
-				      cb->compressed_len);
-csum_failed:
-	if (ret)
-		cb->errors = 1;
-
-	/* release the compressed pages */
-	index = 0;
-	for (index = 0; index < cb->nr_pages; index++) {
-		page = cb->compressed_pages[index];
-		page->mapping = NULL;
-		page_cache_release(page);
-	}
-
-	/* do io completion on the original bio */
-	if (cb->errors) {
-		bio_io_error(cb->orig_bio);
-	} else {
-		int bio_index = 0;
-		struct bio_vec *bvec = cb->orig_bio->bi_io_vec;
-
-		/*
-		 * we have verified the checksum already, set page
-		 * checked so the end_io handlers know about it
-		 */
-		while (bio_index < cb->orig_bio->bi_vcnt) {
-			SetPageChecked(bvec->bv_page);
-			bvec++;
-			bio_index++;
-		}
-		bio_endio(cb->orig_bio, 0);
-	}
-
-	/* finally free the cb struct */
-	kfree(cb->compressed_pages);
-	kfree(cb);
-out:
-	bio_put(bio);
-}
-
-/*
- * Clear the writeback bits on all of the file
- * pages for a compressed write
- */
-static noinline void end_compressed_writeback(struct inode *inode, u64 start,
-					      unsigned long ram_size)
-{
-	unsigned long index = start >> PAGE_CACHE_SHIFT;
-	unsigned long end_index = (start + ram_size - 1) >> PAGE_CACHE_SHIFT;
-	struct page *pages[16];
-	unsigned long nr_pages = end_index - index + 1;
-	int i;
-	int ret;
-
-	while (nr_pages > 0) {
-		ret = find_get_pages_contig(inode->i_mapping, index,
-				     min_t(unsigned long,
-				     nr_pages, ARRAY_SIZE(pages)), pages);
-		if (ret == 0) {
-			nr_pages -= 1;
-			index += 1;
-			continue;
-		}
-		for (i = 0; i < ret; i++) {
-			end_page_writeback(pages[i]);
-			page_cache_release(pages[i]);
-		}
-		nr_pages -= ret;
-		index += ret;
-	}
-	/* the inode may be gone now */
-}
-
-/*
- * do the cleanup once all the compressed pages hit the disk.
- * This will clear writeback on the file pages and free the compressed
- * pages.
- *
- * This also calls the writeback end hooks for the file pages so that
- * metadata and checksums can be updated in the file.
- */
-static void end_compressed_bio_write(struct bio *bio, int err)
-{
-	struct extent_io_tree *tree;
-	struct compressed_bio *cb = bio->bi_private;
-	struct inode *inode;
-	struct page *page;
-	unsigned long index;
-
-	if (err)
-		cb->errors = 1;
-
-	/* if there are more bios still pending for this compressed
-	 * extent, just exit
-	 */
-	if (!atomic_dec_and_test(&cb->pending_bios))
-		goto out;
-
-	/* ok, we're the last bio for this extent, step one is to
-	 * call back into the FS and do all the end_io operations
-	 */
-	inode = cb->inode;
-	tree = &BTRFS_I(inode)->io_tree;
-	cb->compressed_pages[0]->mapping = cb->inode->i_mapping;
-	tree->ops->writepage_end_io_hook(cb->compressed_pages[0],
-					 cb->start,
-					 cb->start + cb->len - 1,
-					 NULL, 1);
-	cb->compressed_pages[0]->mapping = NULL;
-
-	end_compressed_writeback(inode, cb->start, cb->len);
-	/* note, our inode could be gone now */
-
-	/*
-	 * release the compressed pages, these came from alloc_page and
-	 * are not attached to the inode at all
-	 */
-	index = 0;
-	for (index = 0; index < cb->nr_pages; index++) {
-		page = cb->compressed_pages[index];
-		page->mapping = NULL;
-		page_cache_release(page);
-	}
-
-	/* finally free the cb struct */
-	kfree(cb->compressed_pages);
-	kfree(cb);
-out:
-	bio_put(bio);
-}
-
-/*
- * worker function to build and submit bios for previously compressed pages.
- * The corresponding pages in the inode should be marked for writeback
- * and the compressed pages should have a reference on them for dropping
- * when the IO is complete.
- *
- * This also checksums the file bytes and gets things ready for
- * the end io hooks.
- */
-int btrfs_submit_compressed_write(struct inode *inode, u64 start,
-				 unsigned long len, u64 disk_start,
-				 unsigned long compressed_len,
-				 struct page **compressed_pages,
-				 unsigned long nr_pages)
-{
-	struct bio *bio = NULL;
-	struct btrfs_root *root = BTRFS_I(inode)->root;
-	struct compressed_bio *cb;
-	unsigned long bytes_left;
-	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
-	int pg_index = 0;
-	struct page *page;
-	u64 first_byte = disk_start;
-	struct block_device *bdev;
-	int ret;
-	int skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
-
-	WARN_ON(start & ((u64)PAGE_CACHE_SIZE - 1));
-	cb = kmalloc(compressed_bio_size(root, compressed_len), GFP_NOFS);
-	if (!cb)
-		return -ENOMEM;
-	atomic_set(&cb->pending_bios, 0);
-	cb->errors = 0;
-	cb->inode = inode;
-	cb->start = start;
-	cb->len = len;
-	cb->mirror_num = 0;
-	cb->compressed_pages = compressed_pages;
-	cb->compressed_len = compressed_len;
-	cb->orig_bio = NULL;
-	cb->nr_pages = nr_pages;
-
-	bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
-
-	bio = compressed_bio_alloc(bdev, first_byte, GFP_NOFS);
-	if(!bio) {
-		kfree(cb);
-		return -ENOMEM;
-	}
-	bio->bi_private = cb;
-	bio->bi_end_io = end_compressed_bio_write;
-	atomic_inc(&cb->pending_bios);
-
-	/* create and submit bios for the compressed pages */
-	bytes_left = compressed_len;
-	for (pg_index = 0; pg_index < cb->nr_pages; pg_index++) {
-		page = compressed_pages[pg_index];
-		page->mapping = inode->i_mapping;
-		if (bio->bi_size)
-			ret = io_tree->ops->merge_bio_hook(page, 0,
-							   PAGE_CACHE_SIZE,
-							   bio, 0);
-		else
-			ret = 0;
-
-		page->mapping = NULL;
-		if (ret || bio_add_page(bio, page, PAGE_CACHE_SIZE, 0) <
-		    PAGE_CACHE_SIZE) {
-			bio_get(bio);
-
-			/*
-			 * inc the count before we submit the bio so
-			 * we know the end IO handler won't happen before
-			 * we inc the count.  Otherwise, the cb might get
-			 * freed before we're done setting it up
-			 */
-			atomic_inc(&cb->pending_bios);
-			ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
-			BUG_ON(ret); /* -ENOMEM */
-
-			if (!skip_sum) {
-				ret = btrfs_csum_one_bio(root, inode, bio,
-							 start, 1);
-				BUG_ON(ret); /* -ENOMEM */
-			}
-
-			ret = btrfs_map_bio(root, WRITE, bio, 0, 1);
-			BUG_ON(ret); /* -ENOMEM */
-
-			bio_put(bio);
-
-			bio = compressed_bio_alloc(bdev, first_byte, GFP_NOFS);
-			BUG_ON(!bio);
-			bio->bi_private = cb;
-			bio->bi_end_io = end_compressed_bio_write;
-			bio_add_page(bio, page, PAGE_CACHE_SIZE, 0);
-		}
-		if (bytes_left < PAGE_CACHE_SIZE) {
-			printk("bytes left %lu compress len %lu nr %lu\n",
-			       bytes_left, cb->compressed_len, cb->nr_pages);
-		}
-		bytes_left -= PAGE_CACHE_SIZE;
-		first_byte += PAGE_CACHE_SIZE;
-		cond_resched();
-	}
-	bio_get(bio);
-
-	ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
-	BUG_ON(ret); /* -ENOMEM */
-
-	if (!skip_sum) {
-		ret = btrfs_csum_one_bio(root, inode, bio, start, 1);
-		BUG_ON(ret); /* -ENOMEM */
-	}
-
-	ret = btrfs_map_bio(root, WRITE, bio, 0, 1);
-	BUG_ON(ret); /* -ENOMEM */
-
-	bio_put(bio);
-	return 0;
-}
-
-static noinline int add_ra_bio_pages(struct inode *inode,
-				     u64 compressed_end,
-				     struct compressed_bio *cb)
-{
-	unsigned long end_index;
-	unsigned long pg_index;
-	u64 last_offset;
-	u64 isize = i_size_read(inode);
-	int ret;
-	struct page *page;
-	unsigned long nr_pages = 0;
-	struct extent_map *em;
-	struct address_space *mapping = inode->i_mapping;
-	struct extent_map_tree *em_tree;
-	struct extent_io_tree *tree;
-	u64 end;
-	int misses = 0;
-
-	page = cb->orig_bio->bi_io_vec[cb->orig_bio->bi_vcnt - 1].bv_page;
-	last_offset = (page_offset(page) + PAGE_CACHE_SIZE);
-	em_tree = &BTRFS_I(inode)->extent_tree;
-	tree = &BTRFS_I(inode)->io_tree;
-
-	if (isize == 0)
-		return 0;
-
-	end_index = (i_size_read(inode) - 1) >> PAGE_CACHE_SHIFT;
-
-	while (last_offset < compressed_end) {
-		pg_index = last_offset >> PAGE_CACHE_SHIFT;
-
-		if (pg_index > end_index)
-			break;
-
-		rcu_read_lock();
-		page = radix_tree_lookup(&mapping->page_tree, pg_index);
-		rcu_read_unlock();
-		if (page) {
-			misses++;
-			if (misses > 4)
-				break;
-			goto next;
-		}
-
-		page = __page_cache_alloc(mapping_gfp_mask(mapping) &
-								~__GFP_FS);
-		if (!page)
-			break;
-
-		if (add_to_page_cache_lru(page, mapping, pg_index,
-								GFP_NOFS)) {
-			page_cache_release(page);
-			goto next;
-		}
-
-		end = last_offset + PAGE_CACHE_SIZE - 1;
-		/*
-		 * at this point, we have a locked page in the page cache
-		 * for these bytes in the file.  But, we have to make
-		 * sure they map to this compressed extent on disk.
-		 */
-		set_page_extent_mapped(page);
-		lock_extent(tree, last_offset, end);
-		read_lock(&em_tree->lock);
-		em = lookup_extent_mapping(em_tree, last_offset,
-					   PAGE_CACHE_SIZE);
-		read_unlock(&em_tree->lock);
-
-		if (!em || last_offset < em->start ||
-		    (last_offset + PAGE_CACHE_SIZE > extent_map_end(em)) ||
-		    (em->block_start >> 9) != cb->orig_bio->bi_sector) {
-			free_extent_map(em);
-			unlock_extent(tree, last_offset, end);
-			unlock_page(page);
-			page_cache_release(page);
-			break;
-		}
-		free_extent_map(em);
-
-		if (page->index == end_index) {
-			char *userpage;
-			size_t zero_offset = isize & (PAGE_CACHE_SIZE - 1);
-
-			if (zero_offset) {
-				int zeros;
-				zeros = PAGE_CACHE_SIZE - zero_offset;
-				userpage = kmap_atomic(page);
-				memset(userpage + zero_offset, 0, zeros);
-				flush_dcache_page(page);
-				kunmap_atomic(userpage);
-			}
-		}
-
-		ret = bio_add_page(cb->orig_bio, page,
-				   PAGE_CACHE_SIZE, 0);
-
-		if (ret == PAGE_CACHE_SIZE) {
-			nr_pages++;
-			page_cache_release(page);
-		} else {
-			unlock_extent(tree, last_offset, end);
-			unlock_page(page);
-			page_cache_release(page);
-			break;
-		}
-next:
-		last_offset += PAGE_CACHE_SIZE;
-	}
-	return 0;
-}
-
-/*
- * for a compressed read, the bio we get passed has all the inode pages
- * in it.  We don't actually do IO on those pages but allocate new ones
- * to hold the compressed pages on disk.
- *
- * bio->bi_sector points to the compressed extent on disk
- * bio->bi_io_vec points to all of the inode pages
- * bio->bi_vcnt is a count of pages
- *
- * After the compressed pages are read, we copy the bytes into the
- * bio we were passed and then call the bio end_io calls
- */
-int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
-				 int mirror_num, unsigned long bio_flags)
-{
-	struct extent_io_tree *tree;
-	struct extent_map_tree *em_tree;
-	struct compressed_bio *cb;
-	struct btrfs_root *root = BTRFS_I(inode)->root;
-	unsigned long uncompressed_len = bio->bi_vcnt * PAGE_CACHE_SIZE;
-	unsigned long compressed_len;
-	unsigned long nr_pages;
-	unsigned long pg_index;
-	struct page *page;
-	struct block_device *bdev;
-	struct bio *comp_bio;
-	u64 cur_disk_byte = (u64)bio->bi_sector << 9;
-	u64 em_len;
-	u64 em_start;
-	struct extent_map *em;
-	int ret = -ENOMEM;
-	u32 *sums;
-
-	tree = &BTRFS_I(inode)->io_tree;
-	em_tree = &BTRFS_I(inode)->extent_tree;
-
-	/* we need the actual starting offset of this extent in the file */
-	read_lock(&em_tree->lock);
-	em = lookup_extent_mapping(em_tree,
-				   page_offset(bio->bi_io_vec->bv_page),
-				   PAGE_CACHE_SIZE);
-	read_unlock(&em_tree->lock);
-	if (!em)
-		return -EIO;
-
-	compressed_len = em->block_len;
-	cb = kmalloc(compressed_bio_size(root, compressed_len), GFP_NOFS);
-	if (!cb)
-		goto out;
-
-	atomic_set(&cb->pending_bios, 0);
-	cb->errors = 0;
-	cb->inode = inode;
-	cb->mirror_num = mirror_num;
-	sums = &cb->sums;
-
-	cb->start = em->orig_start;
-	em_len = em->len;
-	em_start = em->start;
-
-	free_extent_map(em);
-	em = NULL;
-
-	cb->len = uncompressed_len;
-	cb->compressed_len = compressed_len;
-	cb->compress_type = extent_compress_type(bio_flags);
-	cb->orig_bio = bio;
-
-	nr_pages = (compressed_len + PAGE_CACHE_SIZE - 1) /
-				 PAGE_CACHE_SIZE;
-	cb->compressed_pages = kzalloc(sizeof(struct page *) * nr_pages,
-				       GFP_NOFS);
-	if (!cb->compressed_pages)
-		goto fail1;
-
-	bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
-
-	for (pg_index = 0; pg_index < nr_pages; pg_index++) {
-		cb->compressed_pages[pg_index] = alloc_page(GFP_NOFS |
-							      __GFP_HIGHMEM);
-		if (!cb->compressed_pages[pg_index])
-			goto fail2;
-	}
-	cb->nr_pages = nr_pages;
-
-	add_ra_bio_pages(inode, em_start + em_len, cb);
-
-	/* include any pages we added in add_ra-bio_pages */
-	uncompressed_len = bio->bi_vcnt * PAGE_CACHE_SIZE;
-	cb->len = uncompressed_len;
-
-	comp_bio = compressed_bio_alloc(bdev, cur_disk_byte, GFP_NOFS);
-	if (!comp_bio)
-		goto fail2;
-	comp_bio->bi_private = cb;
-	comp_bio->bi_end_io = end_compressed_bio_read;
-	atomic_inc(&cb->pending_bios);
-
-	for (pg_index = 0; pg_index < nr_pages; pg_index++) {
-		page = cb->compressed_pages[pg_index];
-		page->mapping = inode->i_mapping;
-		page->index = em_start >> PAGE_CACHE_SHIFT;
-
-		if (comp_bio->bi_size)
-			ret = tree->ops->merge_bio_hook(page, 0,
-							PAGE_CACHE_SIZE,
-							comp_bio, 0);
-		else
-			ret = 0;
-
-		page->mapping = NULL;
-		if (ret || bio_add_page(comp_bio, page, PAGE_CACHE_SIZE, 0) <
-		    PAGE_CACHE_SIZE) {
-			bio_get(comp_bio);
-
-			ret = btrfs_bio_wq_end_io(root->fs_info, comp_bio, 0);
-			BUG_ON(ret); /* -ENOMEM */
-
-			/*
-			 * inc the count before we submit the bio so
-			 * we know the end IO handler won't happen before
-			 * we inc the count.  Otherwise, the cb might get
-			 * freed before we're done setting it up
-			 */
-			atomic_inc(&cb->pending_bios);
-
-			if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
-				ret = btrfs_lookup_bio_sums(root, inode,
-							comp_bio, sums);
-				BUG_ON(ret); /* -ENOMEM */
-			}
-			sums += (comp_bio->bi_size + root->sectorsize - 1) /
-				root->sectorsize;
-
-			ret = btrfs_map_bio(root, READ, comp_bio,
-					    mirror_num, 0);
-			BUG_ON(ret); /* -ENOMEM */
-
-			bio_put(comp_bio);
-
-			comp_bio = compressed_bio_alloc(bdev, cur_disk_byte,
-							GFP_NOFS);
-			BUG_ON(!comp_bio);
-			comp_bio->bi_private = cb;
-			comp_bio->bi_end_io = end_compressed_bio_read;
-
-			bio_add_page(comp_bio, page, PAGE_CACHE_SIZE, 0);
-		}
-		cur_disk_byte += PAGE_CACHE_SIZE;
-	}
-	bio_get(comp_bio);
-
-	ret = btrfs_bio_wq_end_io(root->fs_info, comp_bio, 0);
-	BUG_ON(ret); /* -ENOMEM */
-
-	if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
-		ret = btrfs_lookup_bio_sums(root, inode, comp_bio, sums);
-		BUG_ON(ret); /* -ENOMEM */
-	}
-
-	ret = btrfs_map_bio(root, READ, comp_bio, mirror_num, 0);
-	BUG_ON(ret); /* -ENOMEM */
-
-	bio_put(comp_bio);
-	return 0;
-
-fail2:
-	for (pg_index = 0; pg_index < nr_pages; pg_index++)
-		free_page((unsigned long)cb->compressed_pages[pg_index]);
-
-	kfree(cb->compressed_pages);
-fail1:
-	kfree(cb);
-out:
-	free_extent_map(em);
-	return ret;
-}
-
-static struct list_head comp_idle_workspace[BTRFS_COMPRESS_TYPES];
-static spinlock_t comp_workspace_lock[BTRFS_COMPRESS_TYPES];
-static int comp_num_workspace[BTRFS_COMPRESS_TYPES];
-static atomic_t comp_alloc_workspace[BTRFS_COMPRESS_TYPES];
-static wait_queue_head_t comp_workspace_wait[BTRFS_COMPRESS_TYPES];
-
-struct btrfs_compress_op *btrfs_compress_op[] = {
-	&btrfs_zlib_compress,
-	&btrfs_lzo_compress,
-};
-
-void __init btrfs_init_compress(void)
-{
-	int i;
-
-	for (i = 0; i < BTRFS_COMPRESS_TYPES; i++) {
-		INIT_LIST_HEAD(&comp_idle_workspace[i]);
-		spin_lock_init(&comp_workspace_lock[i]);
-		atomic_set(&comp_alloc_workspace[i], 0);
-		init_waitqueue_head(&comp_workspace_wait[i]);
-	}
-}
-
-/*
- * this finds an available workspace or allocates a new one
- * ERR_PTR is returned if things go bad.
- */
-static struct list_head *find_workspace(int type)
-{
-	struct list_head *workspace;
-	int cpus = num_online_cpus();
-	int idx = type - 1;
-
-	struct list_head *idle_workspace	= &comp_idle_workspace[idx];
-	spinlock_t *workspace_lock		= &comp_workspace_lock[idx];
-	atomic_t *alloc_workspace		= &comp_alloc_workspace[idx];
-	wait_queue_head_t *workspace_wait	= &comp_workspace_wait[idx];
-	int *num_workspace			= &comp_num_workspace[idx];
-again:
-	spin_lock(workspace_lock);
-	if (!list_empty(idle_workspace)) {
-		workspace = idle_workspace->next;
-		list_del(workspace);
-		(*num_workspace)--;
-		spin_unlock(workspace_lock);
-		return workspace;
-
-	}
-	if (atomic_read(alloc_workspace) > cpus) {
-		DEFINE_WAIT(wait);
-
-		spin_unlock(workspace_lock);
-		prepare_to_wait(workspace_wait, &wait, TASK_UNINTERRUPTIBLE);
-		if (atomic_read(alloc_workspace) > cpus && !*num_workspace)
-			schedule();
-		finish_wait(workspace_wait, &wait);
-		goto again;
-	}
-	atomic_inc(alloc_workspace);
-	spin_unlock(workspace_lock);
-
-	workspace = btrfs_compress_op[idx]->alloc_workspace();
-	if (IS_ERR(workspace)) {
-		atomic_dec(alloc_workspace);
-		wake_up(workspace_wait);
-	}
-	return workspace;
-}
-
-/*
- * put a workspace struct back on the list or free it if we have enough
- * idle ones sitting around
- */
-static void free_workspace(int type, struct list_head *workspace)
-{
-	int idx = type - 1;
-	struct list_head *idle_workspace	= &comp_idle_workspace[idx];
-	spinlock_t *workspace_lock		= &comp_workspace_lock[idx];
-	atomic_t *alloc_workspace		= &comp_alloc_workspace[idx];
-	wait_queue_head_t *workspace_wait	= &comp_workspace_wait[idx];
-	int *num_workspace			= &comp_num_workspace[idx];
-
-	spin_lock(workspace_lock);
-	if (*num_workspace < num_online_cpus()) {
-		list_add_tail(workspace, idle_workspace);
-		(*num_workspace)++;
-		spin_unlock(workspace_lock);
-		goto wake;
-	}
-	spin_unlock(workspace_lock);
-
-	btrfs_compress_op[idx]->free_workspace(workspace);
-	atomic_dec(alloc_workspace);
-wake:
-	if (waitqueue_active(workspace_wait))
-		wake_up(workspace_wait);
-}
-
-/*
- * cleanup function for module exit
- */
-static void free_workspaces(void)
-{
-	struct list_head *workspace;
-	int i;
-
-	for (i = 0; i < BTRFS_COMPRESS_TYPES; i++) {
-		while (!list_empty(&comp_idle_workspace[i])) {
-			workspace = comp_idle_workspace[i].next;
-			list_del(workspace);
-			btrfs_compress_op[i]->free_workspace(workspace);
-			atomic_dec(&comp_alloc_workspace[i]);
-		}
-	}
-}
-
-/*
- * given an address space and start/len, compress the bytes.
- *
- * pages are allocated to hold the compressed result and stored
- * in 'pages'
- *
- * out_pages is used to return the number of pages allocated.  There
- * may be pages allocated even if we return an error
- *
- * total_in is used to return the number of bytes actually read.  It
- * may be smaller then len if we had to exit early because we
- * ran out of room in the pages array or because we cross the
- * max_out threshold.
- *
- * total_out is used to return the total number of compressed bytes
- *
- * max_out tells us the max number of bytes that we're allowed to
- * stuff into pages
- */
-int btrfs_compress_pages(int type, struct address_space *mapping,
-			 u64 start, unsigned long len,
-			 struct page **pages,
-			 unsigned long nr_dest_pages,
-			 unsigned long *out_pages,
-			 unsigned long *total_in,
-			 unsigned long *total_out,
-			 unsigned long max_out)
-{
-	struct list_head *workspace;
-	int ret;
-
-	workspace = find_workspace(type);
-	if (IS_ERR(workspace))
-		return -1;
-
-	ret = btrfs_compress_op[type-1]->compress_pages(workspace, mapping,
-						      start, len, pages,
-						      nr_dest_pages, out_pages,
-						      total_in, total_out,
-						      max_out);
-	free_workspace(type, workspace);
-	return ret;
-}
-
-/*
- * pages_in is an array of pages with compressed data.
- *
- * disk_start is the starting logical offset of this array in the file
- *
- * bvec is a bio_vec of pages from the file that we want to decompress into
- *
- * vcnt is the count of pages in the biovec
- *
- * srclen is the number of bytes in pages_in
- *
- * The basic idea is that we have a bio that was created by readpages.
- * The pages in the bio are for the uncompressed data, and they may not
- * be contiguous.  They all correspond to the range of bytes covered by
- * the compressed extent.
- */
-int btrfs_decompress_biovec(int type, struct page **pages_in, u64 disk_start,
-			    struct bio_vec *bvec, int vcnt, size_t srclen)
-{
-	struct list_head *workspace;
-	int ret;
-
-	workspace = find_workspace(type);
-	if (IS_ERR(workspace))
-		return -ENOMEM;
-
-	ret = btrfs_compress_op[type-1]->decompress_biovec(workspace, pages_in,
-							 disk_start,
-							 bvec, vcnt, srclen);
-	free_workspace(type, workspace);
-	return ret;
-}
-
-/*
- * a less complex decompression routine.  Our compressed data fits in a
- * single page, and we want to read a single page out of it.
- * start_byte tells us the offset into the compressed data we're interested in
- */
-int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page,
-		     unsigned long start_byte, size_t srclen, size_t destlen)
-{
-	struct list_head *workspace;
-	int ret;
-
-	workspace = find_workspace(type);
-	if (IS_ERR(workspace))
-		return -ENOMEM;
-
-	ret = btrfs_compress_op[type-1]->decompress(workspace, data_in,
-						  dest_page, start_byte,
-						  srclen, destlen);
-
-	free_workspace(type, workspace);
-	return ret;
-}
-
-void btrfs_exit_compress(void)
-{
-	free_workspaces();
-}
-
-/*
- * Copy uncompressed data from working buffer to pages.
- *
- * buf_start is the byte offset we're of the start of our workspace buffer.
- *
- * total_out is the last byte of the buffer
- */
-int btrfs_decompress_buf2page(char *buf, unsigned long buf_start,
-			      unsigned long total_out, u64 disk_start,
-			      struct bio_vec *bvec, int vcnt,
-			      unsigned long *pg_index,
-			      unsigned long *pg_offset)
-{
-	unsigned long buf_offset;
-	unsigned long current_buf_start;
-	unsigned long start_byte;
-	unsigned long working_bytes = total_out - buf_start;
-	unsigned long bytes;
-	char *kaddr;
-	struct page *page_out = bvec[*pg_index].bv_page;
-
-	/*
-	 * start byte is the first byte of the page we're currently
-	 * copying into relative to the start of the compressed data.
-	 */
-	start_byte = page_offset(page_out) - disk_start;
-
-	/* we haven't yet hit data corresponding to this page */
-	if (total_out <= start_byte)
-		return 1;
-
-	/*
-	 * the start of the data we care about is offset into
-	 * the middle of our working buffer
-	 */
-	if (total_out > start_byte && buf_start < start_byte) {
-		buf_offset = start_byte - buf_start;
-		working_bytes -= buf_offset;
-	} else {
-		buf_offset = 0;
-	}
-	current_buf_start = buf_start;
-
-	/* copy bytes from the working buffer into the pages */
-	while (working_bytes > 0) {
-		bytes = min(PAGE_CACHE_SIZE - *pg_offset,
-			    PAGE_CACHE_SIZE - buf_offset);
-		bytes = min(bytes, working_bytes);
-		kaddr = kmap_atomic(page_out);
-		memcpy(kaddr + *pg_offset, buf + buf_offset, bytes);
-		kunmap_atomic(kaddr);
-		flush_dcache_page(page_out);
-
-		*pg_offset += bytes;
-		buf_offset += bytes;
-		working_bytes -= bytes;
-		current_buf_start += bytes;
-
-		/* check if we need to pick another page */
-		if (*pg_offset == PAGE_CACHE_SIZE) {
-			(*pg_index)++;
-			if (*pg_index >= vcnt)
-				return 0;
-
-			page_out = bvec[*pg_index].bv_page;
-			*pg_offset = 0;
-			start_byte = page_offset(page_out) - disk_start;
-
-			/*
-			 * make sure our new page is covered by this
-			 * working buffer
-			 */
-			if (total_out <= start_byte)
-				return 1;
-
-			/*
-			 * the next page in the biovec might not be adjacent
-			 * to the last page, but it might still be found
-			 * inside this working buffer. bump our offset pointer
-			 */
-			if (total_out > start_byte &&
-			    current_buf_start < start_byte) {
-				buf_offset = start_byte - buf_start;
-				working_bytes = total_out - start_byte;
-				current_buf_start = buf_start + buf_offset;
-			}
-		}
-	}
-
-	return 1;
-}