Commit 86b9f2ec authored by Yan, Zheng's avatar Yan, Zheng Committed by Chris Mason
Browse files

Btrfs: Fix per root used space accounting 



The bytes_used field in root item was originally planned to
trace the amount of used data and tree blocks. But it never
worked right since we can't trace freeing of data accurately.
This patch changes it to only trace the amount of tree blocks.

Signed-off-by: default avatarYan Zheng <zheng.yan@oracle.com>
Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent 55ef6899

fs/btrfs/ctree.c

+14 −17
Original line number Diff line number Diff line
@@ -456,9 +456,8 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, 
		extent_buffer_get(cow);

		spin_unlock(&root->node_lock);



		btrfs_free_extent(trans, root, buf->start, buf->len,

				  parent_start, root->root_key.objectid,

				  level, 0);

		btrfs_free_tree_block(trans, root, buf->start, buf->len,

				parent_start, root->root_key.objectid, level);

		free_extent_buffer(buf);

		add_root_to_dirty_list(root);

	} else {
@@ -473,9 +472,8 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, 
		btrfs_set_node_ptr_generation(parent, parent_slot,

					      trans->transid);

		btrfs_mark_buffer_dirty(parent);

		btrfs_free_extent(trans, root, buf->start, buf->len,

				  parent_start, root->root_key.objectid,

				  level, 0);

		btrfs_free_tree_block(trans, root, buf->start, buf->len,

				parent_start, root->root_key.objectid, level);

	}

	if (unlock_orig)

		btrfs_tree_unlock(buf);
@@ -1035,8 +1033,8 @@ static noinline int balance_level(struct btrfs_trans_handle *trans, 
		btrfs_tree_unlock(mid);

		/* once for the path */

		free_extent_buffer(mid);

		ret = btrfs_free_extent(trans, root, mid->start, mid->len,

					0, root->root_key.objectid, level, 1);

		ret = btrfs_free_tree_block(trans, root, mid->start, mid->len,

					    0, root->root_key.objectid, level);

		/* once for the root ptr */

		free_extent_buffer(mid);

		return ret;
@@ -1100,10 +1098,10 @@ static noinline int balance_level(struct btrfs_trans_handle *trans, 
				       1);

			if (wret)

				ret = wret;

			wret = btrfs_free_extent(trans, root, bytenr,

						 blocksize, 0,

			wret = btrfs_free_tree_block(trans, root,

						     bytenr, blocksize, 0,

						     root->root_key.objectid,

						 level, 0);

						     level);

			if (wret)

				ret = wret;

		} else {
@@ -1148,9 +1146,8 @@ static noinline int balance_level(struct btrfs_trans_handle *trans, 
		wret = del_ptr(trans, root, path, level + 1, pslot);

		if (wret)

			ret = wret;

		wret = btrfs_free_extent(trans, root, bytenr, blocksize,

					 0, root->root_key.objectid,

					 level, 0);

		wret = btrfs_free_tree_block(trans, root, bytenr, blocksize,

					 0, root->root_key.objectid, level);

		if (wret)

			ret = wret;

	} else {
@@ -3794,8 +3791,8 @@ static noinline int btrfs_del_leaf(struct btrfs_trans_handle *trans, 
	 */

	btrfs_unlock_up_safe(path, 0);



	ret = btrfs_free_extent(trans, root, leaf->start, leaf->len,

				0, root->root_key.objectid, 0, 0);

	ret = btrfs_free_tree_block(trans, root, leaf->start, leaf->len,

				    0, root->root_key.objectid, 0);

	return ret;

}

/*

fs/btrfs/ctree.h

+4 −0
Original line number Diff line number Diff line
@@ -1982,6 +1982,10 @@ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, 
					u64 parent, u64 root_objectid,

					struct btrfs_disk_key *key, int level,

					u64 hint, u64 empty_size);

int btrfs_free_tree_block(struct btrfs_trans_handle *trans,

			  struct btrfs_root *root,

			  u64 bytenr, u32 blocksize,

			  u64 parent, u64 root_objectid, int level);

struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,

					    struct btrfs_root *root,

					    u64 bytenr, u32 blocksize,

fs/btrfs/extent-tree.c

+23 −8
Original line number Diff line number Diff line
@@ -3454,14 +3454,6 @@ static int update_block_group(struct btrfs_trans_handle *trans, 
	else

		old_val -= num_bytes;

	btrfs_set_super_bytes_used(&info->super_copy, old_val);



	/* block accounting for root item */

	old_val = btrfs_root_used(&root->root_item);

	if (alloc)

		old_val += num_bytes;

	else

		old_val -= num_bytes;

	btrfs_set_root_used(&root->root_item, old_val);

	spin_unlock(&info->delalloc_lock);



	while (total) {
@@ -4049,6 +4041,21 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans, 
	return ret;

}



int btrfs_free_tree_block(struct btrfs_trans_handle *trans,

			  struct btrfs_root *root,

			  u64 bytenr, u32 blocksize,

			  u64 parent, u64 root_objectid, int level)

{

	u64 used;

	spin_lock(&root->node_lock);

	used = btrfs_root_used(&root->root_item) - blocksize;

	btrfs_set_root_used(&root->root_item, used);

	spin_unlock(&root->node_lock);



	return btrfs_free_extent(trans, root, bytenr, blocksize,

				 parent, root_objectid, level, 0);

}



static u64 stripe_align(struct btrfs_root *root, u64 val)

{

	u64 mask = ((u64)root->stripesize - 1);
@@ -4897,6 +4904,14 @@ static int alloc_tree_block(struct btrfs_trans_handle *trans, 
					extent_op);

		BUG_ON(ret);

	}



	if (root_objectid == root->root_key.objectid) {

		u64 used;

		spin_lock(&root->node_lock);

		used = btrfs_root_used(&root->root_item) + num_bytes;

		btrfs_set_root_used(&root->root_item, used);

		spin_unlock(&root->node_lock);

	}

	return ret;

}

fs/btrfs/ioctl.c

+1 −1
Original line number Diff line number Diff line
@@ -289,7 +289,7 @@ static noinline int create_subvol(struct btrfs_root *root, 
	btrfs_set_root_generation(&root_item, trans->transid);

	btrfs_set_root_level(&root_item, 0);

	btrfs_set_root_refs(&root_item, 1);

	btrfs_set_root_used(&root_item, 0);

	btrfs_set_root_used(&root_item, leaf->len);

	btrfs_set_root_last_snapshot(&root_item, 0);



	memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));

fs/btrfs/transaction.c

+5 −1
Original line number Diff line number Diff line
@@ -501,13 +501,16 @@ static int update_cowonly_root(struct btrfs_trans_handle *trans, 
{

	int ret;

	u64 old_root_bytenr;

	u64 old_root_used;

	struct btrfs_root *tree_root = root->fs_info->tree_root;



	old_root_used = btrfs_root_used(&root->root_item);

	btrfs_write_dirty_block_groups(trans, root);



	while (1) {

		old_root_bytenr = btrfs_root_bytenr(&root->root_item);

		if (old_root_bytenr == root->node->start)

		if (old_root_bytenr == root->node->start &&

		    old_root_used == btrfs_root_used(&root->root_item))

			break;



		btrfs_set_root_node(&root->root_item, root->node);
@@ -516,6 +519,7 @@ static int update_cowonly_root(struct btrfs_trans_handle *trans, 
					&root->root_item);

		BUG_ON(ret);



		old_root_used = btrfs_root_used(&root->root_item);

		ret = btrfs_write_dirty_block_groups(trans, root);

		BUG_ON(ret);

	}

CRA Git | Maintained and supported by SUSTech CRA and CCSE