Btrfs: Make the resizer work based on shrinking and growing devices (8f18cf13) · Commits · e / devices / android_kernel_teracube_emerald

fs/btrfs/ctree.h

+1 −0

Original line number	Original line	Diff line number	Diff line
	@@ -474,6 +474,7 @@ struct btrfs_block_group_cache {
	u64 pinned;		u64 pinned;
	u64 flags;		u64 flags;
	int cached;		int cached;
			int ro;
	};		};

	struct btrfs_device;		struct btrfs_device;

fs/btrfs/disk-io.c

+4 −0

Original line number	Original line	Diff line number	Diff line
	@@ -818,6 +818,10 @@ struct btrfs_root btrfs_read_fs_root_no_name(struct btrfs_fs_info fs_info,
	return fs_info->tree_root;		return fs_info->tree_root;
	if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)		if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
	return fs_info->extent_root;		return fs_info->extent_root;
			if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
			return fs_info->chunk_root;
			if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
			return fs_info->dev_root;

	root = radix_tree_lookup(&fs_info->fs_roots_radix,		root = radix_tree_lookup(&fs_info->fs_roots_radix,
	(unsigned long)location->objectid);		(unsigned long)location->objectid);

fs/btrfs/extent-tree.c

+57 −88

Original line number	Original line	Diff line number	Diff line
	@@ -187,6 +187,7 @@ static int noinline find_search_start(struct btrfs_root *root,

	if (!cache)		if (!cache)
	goto out;		goto out;

	total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);		total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
	free_space_cache = &root->fs_info->free_space_cache;		free_space_cache = &root->fs_info->free_space_cache;

	@@ -196,7 +197,7 @@ static int noinline find_search_start(struct btrfs_root *root,
	goto out;		goto out;

	last = max(search_start, cache->key.objectid);		last = max(search_start, cache->key.objectid);
	if (!block_group_bits(cache, data)) {		if (!block_group_bits(cache, data) \|\| cache->ro) {
	goto new_group;		goto new_group;
	}		}

	@@ -221,6 +222,8 @@ static int noinline find_search_start(struct btrfs_root *root,
	continue;		continue;
	}		}
	spin_unlock_irq(&free_space_cache->lock);		spin_unlock_irq(&free_space_cache->lock);
			if (cache->ro)
			goto new_group;
	if (start + num > cache->key.objectid + cache->key.offset)		if (start + num > cache->key.objectid + cache->key.offset)
	goto new_group;		goto new_group;
	if (start + num > total_fs_bytes)		if (start + num > total_fs_bytes)
	@@ -319,7 +322,7 @@ struct btrfs_block_group_cache btrfs_find_block_group(struct btrfs_root root,
	if (search_start && search_start < total_fs_bytes) {		if (search_start && search_start < total_fs_bytes) {
	struct btrfs_block_group_cache *shint;		struct btrfs_block_group_cache *shint;
	shint = btrfs_lookup_block_group(info, search_start);		shint = btrfs_lookup_block_group(info, search_start);
	if (shint && block_group_bits(shint, data)) {		if (shint && block_group_bits(shint, data) && !shint->ro) {
	used = btrfs_block_group_used(&shint->item);		used = btrfs_block_group_used(&shint->item);
	if (used + shint->pinned <		if (used + shint->pinned <
	div_factor(shint->key.offset, factor)) {		div_factor(shint->key.offset, factor)) {
	@@ -327,7 +330,7 @@ struct btrfs_block_group_cache btrfs_find_block_group(struct btrfs_root root,
	}		}
	}		}
	}		}
	if (hint && block_group_bits(hint, data) &&		if (hint && !hint->ro && block_group_bits(hint, data) &&
	hint->key.objectid < total_fs_bytes) {		hint->key.objectid < total_fs_bytes) {
	used = btrfs_block_group_used(&hint->item);		used = btrfs_block_group_used(&hint->item);
	if (used + hint->pinned <		if (used + hint->pinned <
	@@ -364,7 +367,7 @@ struct btrfs_block_group_cache btrfs_find_block_group(struct btrfs_root root,
	if (cache->key.objectid > total_fs_bytes)		if (cache->key.objectid > total_fs_bytes)
	break;		break;

	if (block_group_bits(cache, data)) {		if (!cache->ro && block_group_bits(cache, data)) {
	if (full_search)		if (full_search)
	free_check = cache->key.offset;		free_check = cache->key.offset;
	else		else
	@@ -1020,6 +1023,7 @@ static int update_space_info(struct btrfs_fs_info *info, u64 flags,
	if (found) {		if (found) {
	found->total_bytes += total_bytes;		found->total_bytes += total_bytes;
	found->bytes_used += bytes_used;		found->bytes_used += bytes_used;
			found->full = 0;
	WARN_ON(found->total_bytes < found->bytes_used);		WARN_ON(found->total_bytes < found->bytes_used);
	*space_info = found;		*space_info = found;
	return 0;		return 0;
	@@ -1700,7 +1704,6 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
	u64 super_used;		u64 super_used;
	u64 root_used;		u64 root_used;
	u64 search_start = 0;		u64 search_start = 0;
	u64 new_hint;
	u64 alloc_profile;		u64 alloc_profile;
	u32 sizes[2];		u32 sizes[2];
	struct btrfs_fs_info *info = root->fs_info;		struct btrfs_fs_info *info = root->fs_info;
	@@ -1724,7 +1727,7 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
	data = BTRFS_BLOCK_GROUP_METADATA \| alloc_profile;		data = BTRFS_BLOCK_GROUP_METADATA \| alloc_profile;
	}		}
	again:		again:
	if (root->ref_cows) {		if (root != root->fs_info->extent_root) {
	if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {		if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {
	ret = do_chunk_alloc(trans, root->fs_info->extent_root,		ret = do_chunk_alloc(trans, root->fs_info->extent_root,
	2 * 1024 * 1024,		2 * 1024 * 1024,
	@@ -1738,10 +1741,6 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
	BUG_ON(ret);		BUG_ON(ret);
	}		}

	new_hint = max(hint_byte, root->fs_info->alloc_start);
	if (new_hint < btrfs_super_total_bytes(&info->super_copy))
	hint_byte = new_hint;

	WARN_ON(num_bytes < root->sectorsize);		WARN_ON(num_bytes < root->sectorsize);
	ret = find_free_extent(trans, root, num_bytes, empty_size,		ret = find_free_extent(trans, root, num_bytes, empty_size,
	search_start, search_end, hint_byte, ins,		search_start, search_end, hint_byte, ins,
	@@ -2473,15 +2472,16 @@ static int noinline relocate_one_extent(struct btrfs_root *extent_root,
	return ret;		return ret;
	}		}

	int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 new_size)		int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 shrink_start)
	{		{
	struct btrfs_trans_handle *trans;		struct btrfs_trans_handle *trans;
	struct btrfs_root *tree_root = root->fs_info->tree_root;		struct btrfs_root *tree_root = root->fs_info->tree_root;
	struct btrfs_path *path;		struct btrfs_path *path;
	u64 cur_byte;		u64 cur_byte;
	u64 total_found;		u64 total_found;
			u64 shrink_last_byte;
			struct btrfs_block_group_cache *shrink_block_group;
	struct btrfs_fs_info *info = root->fs_info;		struct btrfs_fs_info *info = root->fs_info;
	struct extent_io_tree *block_group_cache;
	struct btrfs_key key;		struct btrfs_key key;
	struct btrfs_key found_key;		struct btrfs_key found_key;
	struct extent_buffer *leaf;		struct extent_buffer *leaf;
	@@ -2489,17 +2489,29 @@ int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 new_size)
	int ret;		int ret;
	int progress = 0;		int progress = 0;

	btrfs_set_super_total_bytes(&info->super_copy, new_size);		shrink_block_group = btrfs_lookup_block_group(root->fs_info,
	clear_extent_dirty(&info->free_space_cache, new_size, (u64)-1,		shrink_start);
	GFP_NOFS);		BUG_ON(!shrink_block_group);
	block_group_cache = &info->block_group_cache;
			shrink_last_byte = shrink_start + shrink_block_group->key.offset;

			shrink_block_group->space_info->total_bytes -=
			shrink_block_group->key.offset;
			printk("shrink_extent_tree %Lu -> %Lu type %Lu\n", shrink_start, shrink_last_byte, shrink_block_group->flags);
	path = btrfs_alloc_path();		path = btrfs_alloc_path();
	root = root->fs_info->extent_root;		root = root->fs_info->extent_root;
	path->reada = 2;		path->reada = 2;

	again:		again:
			trans = btrfs_start_transaction(root, 1);
			do_chunk_alloc(trans, root->fs_info->extent_root,
			btrfs_block_group_used(&shrink_block_group->item) +
			2 * 1024 * 1024, shrink_block_group->flags);
			btrfs_end_transaction(trans, root);
			shrink_block_group->ro = 1;

	total_found = 0;		total_found = 0;
	key.objectid = new_size;		key.objectid = shrink_start;
	key.offset = 0;		key.offset = 0;
	key.type = 0;		key.type = 0;
	cur_byte = key.objectid;		cur_byte = key.objectid;
	@@ -2511,10 +2523,12 @@ int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 new_size)
	ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);		ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);
	if (ret < 0)		if (ret < 0)
	goto out;		goto out;

	if (ret == 0) {		if (ret == 0) {
	leaf = path->nodes[0];		leaf = path->nodes[0];
	btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);		btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
	if (found_key.objectid + found_key.offset > new_size) {		if (found_key.objectid + found_key.offset > shrink_start &&
			found_key.objectid < shrink_last_byte) {
	cur_byte = found_key.objectid;		cur_byte = found_key.objectid;
	key.objectid = cur_byte;		key.objectid = cur_byte;
	}		}
	@@ -2543,6 +2557,9 @@ int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 new_size)

	btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);		btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);

			if (found_key.objectid >= shrink_last_byte)
			break;

	if (progress && need_resched()) {		if (progress && need_resched()) {
	memcpy(&key, &found_key, sizeof(key));		memcpy(&key, &found_key, sizeof(key));
	mutex_unlock(&root->fs_info->fs_mutex);		mutex_unlock(&root->fs_info->fs_mutex);
	@@ -2583,68 +2600,31 @@ int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 new_size)
	goto again;		goto again;
	}		}

			/*
			* we've freed all the extents, now remove the block
			* group item from the tree
			*/
	trans = btrfs_start_transaction(root, 1);		trans = btrfs_start_transaction(root, 1);
	key.objectid = new_size;		memcpy(&key, &shrink_block_group->key, sizeof(key));
	key.offset = 0;
	key.type = 0;
	while(1) {
	u64 ptr;

	ret = btrfs_search_slot(trans, root, &key, path, -1, 1);		ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
			if (ret > 0)
			ret = -EIO;
	if (ret < 0)		if (ret < 0)
	goto out;		goto out;

	leaf = path->nodes[0];		leaf = path->nodes[0];
	nritems = btrfs_header_nritems(leaf);		nritems = btrfs_header_nritems(leaf);
	bg_next:
	if (path->slots[0] >= nritems) {
	ret = btrfs_next_leaf(root, path);
	if (ret < 0)
	break;
	if (ret == 1) {
	ret = 0;
	break;
	}
	leaf = path->nodes[0];
	btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);		btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
			kfree(shrink_block_group);
	/*
	* btrfs_next_leaf doesn't cow buffers, we have to
	* do the search again
	*/
	memcpy(&key, &found_key, sizeof(key));
	btrfs_release_path(root, path);
	goto resched_check;
	}

	btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
	if (btrfs_key_type(&found_key) != BTRFS_BLOCK_GROUP_ITEM_KEY) {
	printk("shrinker found key %Lu %u %Lu\n",
	found_key.objectid, found_key.type,
	found_key.offset);
	path->slots[0]++;
	goto bg_next;
	}
	ret = get_state_private(&info->block_group_cache,
	found_key.objectid, &ptr);
	if (!ret)
	kfree((void *)(unsigned long)ptr);

	clear_extent_bits(&info->block_group_cache, found_key.objectid,		clear_extent_bits(&info->block_group_cache, found_key.objectid,
	found_key.objectid + found_key.offset - 1,		found_key.objectid + found_key.offset - 1,
	(unsigned int)-1, GFP_NOFS);		(unsigned int)-1, GFP_NOFS);

	key.objectid = found_key.objectid + 1;
	btrfs_del_item(trans, root, path);		btrfs_del_item(trans, root, path);
	btrfs_release_path(root, path);		clear_extent_dirty(&info->free_space_cache,
	resched_check:		shrink_start, shrink_last_byte - 1,
	if (need_resched()) {
	mutex_unlock(&root->fs_info->fs_mutex);
	cond_resched();
	mutex_lock(&root->fs_info->fs_mutex);
	}
	}
	clear_extent_dirty(&info->free_space_cache, new_size, (u64)-1,
	GFP_NOFS);		GFP_NOFS);
	btrfs_commit_transaction(trans, root);		btrfs_commit_transaction(trans, root);
	out:		out:
	@@ -2652,13 +2632,6 @@ int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 new_size)
	return ret;		return ret;
	}		}

	int btrfs_grow_extent_tree(struct btrfs_trans_handle *trans,
	struct btrfs_root *root, u64 new_size)
	{
	btrfs_set_super_total_bytes(&root->fs_info->super_copy, new_size);
	return 0;
	}

	int find_first_block_group(struct btrfs_root root, struct btrfs_path path,		int find_first_block_group(struct btrfs_root root, struct btrfs_path path,
	struct btrfs_key *key)		struct btrfs_key *key)
	{		{
	@@ -2726,7 +2699,7 @@ int btrfs_read_block_groups(struct btrfs_root *root)

	leaf = path->nodes[0];		leaf = path->nodes[0];
	btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);		btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
	cache = kmalloc(sizeof(*cache), GFP_NOFS);		cache = kzalloc(sizeof(*cache), GFP_NOFS);
	if (!cache) {		if (!cache) {
	ret = -ENOMEM;		ret = -ENOMEM;
	break;		break;
	@@ -2736,8 +2709,6 @@ int btrfs_read_block_groups(struct btrfs_root *root)
	btrfs_item_ptr_offset(leaf, path->slots[0]),		btrfs_item_ptr_offset(leaf, path->slots[0]),
	sizeof(cache->item));		sizeof(cache->item));
	memcpy(&cache->key, &found_key, sizeof(found_key));		memcpy(&cache->key, &found_key, sizeof(found_key));
	cache->cached = 0;
	cache->pinned = 0;

	key.objectid = found_key.objectid + found_key.offset;		key.objectid = found_key.objectid + found_key.offset;
	btrfs_release_path(root, path);		btrfs_release_path(root, path);
	@@ -2789,12 +2760,10 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
	extent_root = root->fs_info->extent_root;		extent_root = root->fs_info->extent_root;
	block_group_cache = &root->fs_info->block_group_cache;		block_group_cache = &root->fs_info->block_group_cache;

	cache = kmalloc(sizeof(*cache), GFP_NOFS);		cache = kzalloc(sizeof(*cache), GFP_NOFS);
	BUG_ON(!cache);		BUG_ON(!cache);
	cache->key.objectid = chunk_offset;		cache->key.objectid = chunk_offset;
	cache->key.offset = size;		cache->key.offset = size;
	cache->cached = 0;
	cache->pinned = 0;

	btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY);		btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY);
	memset(&cache->item, 0, sizeof(cache->item));		memset(&cache->item, 0, sizeof(cache->item));

fs/btrfs/inode.c

+28 −8

Original line number	Original line	Diff line number	Diff line
	@@ -16,6 +16,7 @@
	* Boston, MA 021110-1307, USA.		* Boston, MA 021110-1307, USA.
	*/		*/

			#include <linux/kernel.h>
	#include <linux/bio.h>		#include <linux/bio.h>
	#include <linux/buffer_head.h>		#include <linux/buffer_head.h>
	#include <linux/fs.h>		#include <linux/fs.h>
	@@ -2887,9 +2888,12 @@ static int btrfs_ioctl_resize(struct btrfs_root root, void __user arg)
	{		{
	u64 new_size;		u64 new_size;
	u64 old_size;		u64 old_size;
			u64 devid = 1;
	struct btrfs_ioctl_vol_args *vol_args;		struct btrfs_ioctl_vol_args *vol_args;
	struct btrfs_trans_handle *trans;		struct btrfs_trans_handle *trans;
			struct btrfs_device *device = NULL;
	char *sizestr;		char *sizestr;
			char *devstr = NULL;
	int ret = 0;		int ret = 0;
	int namelen;		int namelen;
	int mod = 0;		int mod = 0;
	@@ -2909,9 +2913,25 @@ static int btrfs_ioctl_resize(struct btrfs_root root, void __user arg)
	goto out;		goto out;
	}		}

			mutex_lock(&root->fs_info->fs_mutex);
	sizestr = vol_args->name;		sizestr = vol_args->name;
			devstr = strchr(sizestr, ':');
			if (devstr) {
			char *end;
			sizestr = devstr + 1;
			*devstr = '\0';
			devstr = vol_args->name;
			devid = simple_strtoull(devstr, &end, 10);
			printk("resizing devid %Lu\n", devid);
			}
			device = btrfs_find_device(root, devid, NULL);
			if (!device) {
			printk("resizer unable to find device %Lu\n", devid);
			ret = -EINVAL;
			goto out_unlock;
			}
	if (!strcmp(sizestr, "max"))		if (!strcmp(sizestr, "max"))
	new_size = root->fs_info->sb->s_bdev->bd_inode->i_size;		new_size = device->bdev->bd_inode->i_size;
	else {		else {
	if (sizestr[0] == '-') {		if (sizestr[0] == '-') {
	mod = -1;		mod = -1;
	@@ -2923,12 +2943,11 @@ static int btrfs_ioctl_resize(struct btrfs_root root, void __user arg)
	new_size = btrfs_parse_size(sizestr);		new_size = btrfs_parse_size(sizestr);
	if (new_size == 0) {		if (new_size == 0) {
	ret = -EINVAL;		ret = -EINVAL;
	goto out;		goto out_unlock;
	}		}
	}		}

	mutex_lock(&root->fs_info->fs_mutex);		old_size = device->total_bytes;
	old_size = btrfs_super_total_bytes(&root->fs_info->super_copy);

	if (mod < 0) {		if (mod < 0) {
	if (new_size > old_size) {		if (new_size > old_size) {
	@@ -2944,7 +2963,7 @@ static int btrfs_ioctl_resize(struct btrfs_root root, void __user arg)
	ret = -EINVAL;		ret = -EINVAL;
	goto out_unlock;		goto out_unlock;
	}		}
	if (new_size > root->fs_info->sb->s_bdev->bd_inode->i_size) {		if (new_size > device->bdev->bd_inode->i_size) {
	ret = -EFBIG;		ret = -EFBIG;
	goto out_unlock;		goto out_unlock;
	}		}
	@@ -2952,13 +2971,14 @@ static int btrfs_ioctl_resize(struct btrfs_root root, void __user arg)
	do_div(new_size, root->sectorsize);		do_div(new_size, root->sectorsize);
	new_size *= root->sectorsize;		new_size *= root->sectorsize;

	printk("new size is %Lu\n", new_size);		printk("new size for %s is %llu\n", device->name, (unsigned long long)new_size);

	if (new_size > old_size) {		if (new_size > old_size) {
	trans = btrfs_start_transaction(root, 1);		trans = btrfs_start_transaction(root, 1);
	ret = btrfs_grow_extent_tree(trans, root, new_size);		ret = btrfs_grow_device(trans, device, new_size);
	btrfs_commit_transaction(trans, root);		btrfs_commit_transaction(trans, root);
	} else {		} else {
	ret = btrfs_shrink_extent_tree(root, new_size);		ret = btrfs_shrink_device(device, new_size);
	}		}

	out_unlock:		out_unlock:

fs/btrfs/volumes.c

+312 −12

Original line number	Original line	Diff line number	Diff line
	@@ -77,7 +77,7 @@ static struct btrfs_device __find_device(struct list_head head, u64 devid,
	list_for_each(cur, head) {		list_for_each(cur, head) {
	dev = list_entry(cur, struct btrfs_device, dev_list);		dev = list_entry(cur, struct btrfs_device, dev_list);
	if (dev->devid == devid &&		if (dev->devid == devid &&
	!memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE)) {		(!uuid \|\| !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
	return dev;		return dev;
	}		}
	}		}
	@@ -293,6 +293,10 @@ static int find_free_dev_extent(struct btrfs_trans_handle *trans,
	* so we make sure to start at an offset of at least 1MB		* so we make sure to start at an offset of at least 1MB
	*/		*/
	search_start = max((u64)1024 * 1024, search_start);		search_start = max((u64)1024 * 1024, search_start);

			if (root->fs_info->alloc_start + num_bytes <= device->total_bytes)
			search_start = max(root->fs_info->alloc_start, search_start);

	key.objectid = device->devid;		key.objectid = device->devid;
	key.offset = search_start;		key.offset = search_start;
	key.type = BTRFS_DEV_EXTENT_KEY;		key.type = BTRFS_DEV_EXTENT_KEY;
	@@ -380,6 +384,33 @@ static int find_free_dev_extent(struct btrfs_trans_handle *trans,
	return ret;		return ret;
	}		}

			int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
			struct btrfs_device *device,
			u64 start)
			{
			int ret;
			struct btrfs_path *path;
			struct btrfs_root *root = device->dev_root;
			struct btrfs_key key;

			path = btrfs_alloc_path();
			if (!path)
			return -ENOMEM;

			key.objectid = device->devid;
			key.offset = start;
			key.type = BTRFS_DEV_EXTENT_KEY;

			ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
			BUG_ON(ret);

			ret = btrfs_del_item(trans, root, path);
			BUG_ON(ret);

			btrfs_free_path(path);
			return ret;
			}

	int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,		int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
	struct btrfs_device *device,		struct btrfs_device *device,
	u64 chunk_tree, u64 chunk_objectid,		u64 chunk_tree, u64 chunk_objectid,
	@@ -560,6 +591,7 @@ int btrfs_add_device(struct btrfs_trans_handle *trans,
	btrfs_free_path(path);		btrfs_free_path(path);
	return ret;		return ret;
	}		}

	int btrfs_update_device(struct btrfs_trans_handle *trans,		int btrfs_update_device(struct btrfs_trans_handle *trans,
	struct btrfs_device *device)		struct btrfs_device *device)
	{		{
	@@ -606,6 +638,254 @@ int btrfs_update_device(struct btrfs_trans_handle *trans,
	return ret;		return ret;
	}		}

			int btrfs_grow_device(struct btrfs_trans_handle *trans,
			struct btrfs_device *device, u64 new_size)
			{
			struct btrfs_super_block *super_copy =
			&device->dev_root->fs_info->super_copy;
			u64 old_total = btrfs_super_total_bytes(super_copy);
			u64 diff = new_size - device->total_bytes;

			btrfs_set_super_total_bytes(super_copy, old_total + diff);
			return btrfs_update_device(trans, device);
			}

			static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
			struct btrfs_root *root,
			u64 chunk_tree, u64 chunk_objectid,
			u64 chunk_offset)
			{
			int ret;
			struct btrfs_path *path;
			struct btrfs_key key;

			root = root->fs_info->chunk_root;
			path = btrfs_alloc_path();
			if (!path)
			return -ENOMEM;

			key.objectid = chunk_objectid;
			key.offset = chunk_offset;
			key.type = BTRFS_CHUNK_ITEM_KEY;

			ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
			BUG_ON(ret);

			ret = btrfs_del_item(trans, root, path);
			BUG_ON(ret);

			btrfs_free_path(path);
			return 0;
			}

			int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
			chunk_offset)
			{
			struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
			struct btrfs_disk_key *disk_key;
			struct btrfs_chunk *chunk;
			u8 *ptr;
			int ret = 0;
			u32 num_stripes;
			u32 array_size;
			u32 len = 0;
			u32 cur;
			struct btrfs_key key;

			array_size = btrfs_super_sys_array_size(super_copy);

			ptr = super_copy->sys_chunk_array;
			cur = 0;

			while (cur < array_size) {
			disk_key = (struct btrfs_disk_key *)ptr;
			btrfs_disk_key_to_cpu(&key, disk_key);

			len = sizeof(*disk_key);

			if (key.type == BTRFS_CHUNK_ITEM_KEY) {
			chunk = (struct btrfs_chunk *)(ptr + len);
			num_stripes = btrfs_stack_chunk_num_stripes(chunk);
			len += btrfs_chunk_item_size(num_stripes);
			} else {
			ret = -EIO;
			break;
			}
			if (key.objectid == chunk_objectid &&
			key.offset == chunk_offset) {
			memmove(ptr, ptr + len, array_size - (cur + len));
			array_size -= len;
			btrfs_set_super_sys_array_size(super_copy, array_size);
			} else {
			ptr += len;
			cur += len;
			}
			}
			return ret;
			}


			int btrfs_relocate_chunk(struct btrfs_root *root,
			u64 chunk_tree, u64 chunk_objectid,
			u64 chunk_offset)
			{
			struct extent_map_tree *em_tree;
			struct btrfs_root *extent_root;
			struct btrfs_trans_handle *trans;
			struct extent_map *em;
			struct map_lookup *map;
			int ret;
			int i;

			root = root->fs_info->chunk_root;
			extent_root = root->fs_info->extent_root;
			em_tree = &root->fs_info->mapping_tree.map_tree;

			/* step one, relocate all the extents inside this chunk */
			ret = btrfs_shrink_extent_tree(extent_root, chunk_offset);
			BUG_ON(ret);

			trans = btrfs_start_transaction(root, 1);
			BUG_ON(!trans);

			/*
			* step two, delete the device extents and the
			* chunk tree entries
			*/
			spin_lock(&em_tree->lock);
			em = lookup_extent_mapping(em_tree, chunk_offset, 1);
			spin_unlock(&em_tree->lock);

			BUG_ON(em->start > chunk_offset \|\| em->start + em->len < chunk_offset);
			map = (struct map_lookup *)em->bdev;

			for (i = 0; i < map->num_stripes; i++) {
			ret = btrfs_free_dev_extent(trans, map->stripes[i].dev,
			map->stripes[i].physical);
			BUG_ON(ret);
			}
			ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid,
			chunk_offset);

			BUG_ON(ret);

			if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
			ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
			BUG_ON(ret);
			goto out;
			}



			spin_lock(&em_tree->lock);
			remove_extent_mapping(em_tree, em);
			kfree(map);
			em->bdev = NULL;

			/* once for the tree */
			free_extent_map(em);
			spin_unlock(&em_tree->lock);

			out:
			/* once for us */
			free_extent_map(em);

			btrfs_end_transaction(trans, root);
			return 0;
			}

			/*
			* shrinking a device means finding all of the device extents past
			* the new size, and then following the back refs to the chunks.
			* The chunk relocation code actually frees the device extent
			*/
			int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
			{
			struct btrfs_trans_handle *trans;
			struct btrfs_root *root = device->dev_root;
			struct btrfs_dev_extent *dev_extent = NULL;
			struct btrfs_path *path;
			u64 length;
			u64 chunk_tree;
			u64 chunk_objectid;
			u64 chunk_offset;
			int ret;
			int slot;
			struct extent_buffer *l;
			struct btrfs_key key;
			struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
			u64 old_total = btrfs_super_total_bytes(super_copy);
			u64 diff = device->total_bytes - new_size;


			path = btrfs_alloc_path();
			if (!path)
			return -ENOMEM;

			trans = btrfs_start_transaction(root, 1);
			if (!trans) {
			ret = -ENOMEM;
			goto done;
			}

			path->reada = 2;

			device->total_bytes = new_size;
			ret = btrfs_update_device(trans, device);
			if (ret) {
			btrfs_end_transaction(trans, root);
			goto done;
			}
			WARN_ON(diff > old_total);
			btrfs_set_super_total_bytes(super_copy, old_total - diff);
			btrfs_end_transaction(trans, root);

			key.objectid = device->devid;
			key.offset = (u64)-1;
			key.type = BTRFS_DEV_EXTENT_KEY;

			while (1) {
			ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
			if (ret < 0)
			goto done;

			ret = btrfs_previous_item(root, path, 0, key.type);
			if (ret < 0)
			goto done;
			if (ret) {
			ret = 0;
			goto done;
			}

			l = path->nodes[0];
			slot = path->slots[0];
			btrfs_item_key_to_cpu(l, &key, path->slots[0]);

			if (key.objectid != device->devid)
			goto done;

			dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
			length = btrfs_dev_extent_length(l, dev_extent);

			if (key.offset + length <= new_size)
			goto done;

			chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
			chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
			chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
			btrfs_release_path(root, path);

			ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid,
			chunk_offset);
			if (ret)
			goto done;
			}

			done:
			btrfs_free_path(path);
			return ret;
			}

	int btrfs_add_system_chunk(struct btrfs_trans_handle *trans,		int btrfs_add_system_chunk(struct btrfs_trans_handle *trans,
	struct btrfs_root *root,		struct btrfs_root *root,
	struct btrfs_key *key,		struct btrfs_key *key,
	@@ -658,6 +938,7 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
	u64 dev_offset;		u64 dev_offset;
	struct btrfs_fs_info *info = extent_root->fs_info;		struct btrfs_fs_info *info = extent_root->fs_info;
	struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;		struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
			struct btrfs_path *path;
	struct btrfs_stripe *stripes;		struct btrfs_stripe *stripes;
	struct btrfs_device *device = NULL;		struct btrfs_device *device = NULL;
	struct btrfs_chunk *chunk;		struct btrfs_chunk *chunk;
	@@ -724,6 +1005,10 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
	min_stripe_size = 1 * 1024 * 1024;		min_stripe_size = 1 * 1024 * 1024;
	}		}

			path = btrfs_alloc_path();
			if (!path)
			return -ENOMEM;

	/* we don't want a chunk larger than 10% of the FS */		/* we don't want a chunk larger than 10% of the FS */
	percent_max = div_factor(btrfs_super_total_bytes(&info->super_copy), 1);		percent_max = div_factor(btrfs_super_total_bytes(&info->super_copy), 1);
	max_chunk_size = min(percent_max, max_chunk_size);		max_chunk_size = min(percent_max, max_chunk_size);
	@@ -759,11 +1044,19 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,

	avail = device->total_bytes - device->bytes_used;		avail = device->total_bytes - device->bytes_used;
	cur = cur->next;		cur = cur->next;

	if (avail >= min_free) {		if (avail >= min_free) {
	list_move_tail(&device->dev_alloc_list, &private_devs);		u64 ignored_start = 0;
			ret = find_free_dev_extent(trans, device, path,
			min_free,
			&ignored_start);
			if (ret == 0) {
			list_move_tail(&device->dev_alloc_list,
			&private_devs);
	index++;		index++;
	if (type & BTRFS_BLOCK_GROUP_DUP)		if (type & BTRFS_BLOCK_GROUP_DUP)
	index++;		index++;
			}
	} else if (avail > max_avail)		} else if (avail > max_avail)
	max_avail = avail;		max_avail = avail;
	if (cur == dev_list)		if (cur == dev_list)
	@@ -785,30 +1078,37 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
	calc_size = max_avail;		calc_size = max_avail;
	goto again;		goto again;
	}		}
			btrfs_free_path(path);
	return -ENOSPC;		return -ENOSPC;
	}		}
	key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;		key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
	key.type = BTRFS_CHUNK_ITEM_KEY;		key.type = BTRFS_CHUNK_ITEM_KEY;
	ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID,		ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID,
	&key.offset);		&key.offset);
	if (ret)		if (ret) {
			btrfs_free_path(path);
	return ret;		return ret;
			}

	chunk = kmalloc(btrfs_chunk_item_size(num_stripes), GFP_NOFS);		chunk = kmalloc(btrfs_chunk_item_size(num_stripes), GFP_NOFS);
	if (!chunk)		if (!chunk) {
			btrfs_free_path(path);
	return -ENOMEM;		return -ENOMEM;
			}

	map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);		map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
	if (!map) {		if (!map) {
	kfree(chunk);		kfree(chunk);
			btrfs_free_path(path);
	return -ENOMEM;		return -ENOMEM;
	}		}
			btrfs_free_path(path);
			path = NULL;

	stripes = &chunk->stripe;		stripes = &chunk->stripe;
	*num_bytes = chunk_bytes_by_type(type, calc_size,		*num_bytes = chunk_bytes_by_type(type, calc_size,
	num_stripes, sub_stripes);		num_stripes, sub_stripes);


	index = 0;		index = 0;
	printk("new chunk type %Lu start %Lu size %Lu\n", type, key.offset, *num_bytes);		printk("new chunk type %Lu start %Lu size %Lu\n", type, key.offset, *num_bytes);
	while(index < num_stripes) {		while(index < num_stripes) {
	@@ -874,6 +1174,11 @@ printk("alloc chunk start %Lu size %Lu from dev %Lu type %Lu\n", key.offset, cal
	em->len = *num_bytes;		em->len = *num_bytes;
	em->block_start = 0;		em->block_start = 0;

			if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
			ret = btrfs_add_system_chunk(trans, chunk_root, &key,
			chunk, btrfs_chunk_item_size(num_stripes));
			BUG_ON(ret);
			}
	kfree(chunk);		kfree(chunk);

	em_tree = &extent_root->fs_info->mapping_tree.map_tree;		em_tree = &extent_root->fs_info->mapping_tree.map_tree;
	@@ -1376,11 +1681,6 @@ int btrfs_read_sys_array(struct btrfs_root *root)

	array_size = btrfs_super_sys_array_size(super_copy);		array_size = btrfs_super_sys_array_size(super_copy);

	/*
	* we do this loop twice, once for the device items and
	* once for all of the chunks. This way there are device
	* structs filled in for every chunk
	*/
	ptr = super_copy->sys_chunk_array;		ptr = super_copy->sys_chunk_array;
	sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array);		sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array);
	cur = 0;		cur = 0;