Commit 34a38218 authored by Chris Mason's avatar Chris Mason
Browse files

Btrfs: Change push_leaf_{leaf,right} to empty the src leave during item deletion 



Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent e644d021

fs/btrfs/ctree.c

+50 −24
Original line number Diff line number Diff line
@@ -1394,19 +1394,21 @@ int btrfs_leaf_free_space(struct btrfs_root *root, struct extent_buffer *leaf) 
 * room, 0 if everything worked out and < 0 if there were major errors.

 */

static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root

			   *root, struct btrfs_path *path, int data_size)

			   *root, struct btrfs_path *path, int data_size,

			   int empty)

{

	struct extent_buffer *left = path->nodes[0];

	struct extent_buffer *right;

	struct extent_buffer *upper;

	struct btrfs_disk_key disk_key;

	int slot;

	int i;

	u32 i;

	int free_space;

	int push_space = 0;

	int push_items = 0;

	struct btrfs_item *item;

	u32 left_nritems;

	u32 nr;

	u32 right_nritems;

	u32 data_end;

	u32 this_item_size;
@@ -1447,7 +1449,13 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root 
		return 1;

	}



	for (i = left_nritems - 1; i >= 1; i--) {

	if (empty)

		nr = 0;

	else

		nr = 1;



	i = left_nritems - 1;

	while (i >= nr) {

		item = btrfs_item_nr(left, i);



		if (path->slots[0] == i)
@@ -1466,6 +1474,9 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root 
			break;

		push_items++;

		push_space += this_item_size + sizeof(*item);

		if (i == 0)

			break;

		i--;

	}

	if (left->map_token) {

		unmap_extent_buffer(left, left->map_token, KM_USER1);
@@ -1477,11 +1488,12 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root 
		return 1;

	}



	if (push_items == left_nritems)

	if (!empty && push_items == left_nritems)

		WARN_ON(1);



	/* push left to right */

	right_nritems = btrfs_header_nritems(right);



	push_space = btrfs_item_end_nr(left, left_nritems - push_items);

	push_space -= leaf_data_end(root, left);
@@ -1511,7 +1523,6 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root 
	right_nritems += push_items;

	btrfs_set_header_nritems(right, right_nritems);

	push_space = BTRFS_LEAF_DATA_SIZE(root);



	for (i = 0; i < right_nritems; i++) {

		item = btrfs_item_nr(right, i);

		if (!right->map_token) {
@@ -1532,6 +1543,7 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root 
	left_nritems -= push_items;

	btrfs_set_header_nritems(left, left_nritems);



	if (left_nritems)

		btrfs_mark_buffer_dirty(left);

	btrfs_mark_buffer_dirty(right);
@@ -1555,7 +1567,8 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root 
 * least data_size bytes.  returns zero if the push worked, nonzero otherwise

 */

static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root

			  *root, struct btrfs_path *path, int data_size)

			  *root, struct btrfs_path *path, int data_size,

			  int empty)

{

	struct btrfs_disk_key disk_key;

	struct extent_buffer *right = path->nodes[0];
@@ -1568,6 +1581,7 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root 
	struct btrfs_item *item;

	u32 old_left_nritems;

	u32 right_nritems;

	u32 nr;

	int ret = 0;

	int wret;

	u32 this_item_size;
@@ -1607,7 +1621,12 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root 
		return 1;

	}



	for (i = 0; i < right_nritems - 1; i++) {

	if (empty)

		nr = right_nritems;

	else

		nr = right_nritems - 1;



	for (i = 0; i < nr; i++) {

		item = btrfs_item_nr(right, i);

		if (!right->map_token) {

			map_extent_buffer(right, (unsigned long)item,
@@ -1637,7 +1656,7 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root 
		free_extent_buffer(left);

		return 1;

	}

	if (push_items == btrfs_header_nritems(right))

	if (!empty && push_items == btrfs_header_nritems(right))

		WARN_ON(1);



	/* push data from right to left */
@@ -1681,6 +1700,12 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root 
	}



	/* fixup right node */

	if (push_items > right_nritems) {

		printk("push items %d nr %u\n", push_items, right_nritems);

		WARN_ON(1);

	}



	if (push_items < right_nritems) {

		push_space = btrfs_item_offset_nr(right, push_items - 1) -

						  leaf_data_end(root, right);

		memmove_extent_buffer(right, btrfs_leaf_data(right) +
@@ -1693,8 +1718,8 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root 
			     (btrfs_header_nritems(right) - push_items) *

			     sizeof(struct btrfs_item));



	right_nritems = btrfs_header_nritems(right) - push_items;

	btrfs_set_header_nritems(right, right_nritems);

	}

	btrfs_set_header_nritems(right, right_nritems - push_items);

	push_space = BTRFS_LEAF_DATA_SIZE(root);



	for (i = 0; i < right_nritems; i++) {
@@ -1717,6 +1742,7 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root 
	}



	btrfs_mark_buffer_dirty(left);

	if (right_nritems)

		btrfs_mark_buffer_dirty(right);



	btrfs_item_key(right, &disk_key, 0);
@@ -1768,12 +1794,12 @@ static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root 


	/* first try to make some room by pushing left and right */

	if (ins_key->type != BTRFS_DIR_ITEM_KEY) {

		wret = push_leaf_right(trans, root, path, data_size);

		wret = push_leaf_right(trans, root, path, data_size, 0);

		if (wret < 0) {

			return wret;

		}

		if (wret) {

			wret = push_leaf_left(trans, root, path, data_size);

			wret = push_leaf_left(trans, root, path, data_size, 0);

			if (wret < 0)

				return wret;

		}
@@ -2403,13 +2429,13 @@ int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, 
			slot = path->slots[1];

			extent_buffer_get(leaf);



			wret = push_leaf_right(trans, root, path, 1);

			wret = push_leaf_right(trans, root, path, 1, 1);

			if (wret < 0 && wret != -ENOSPC)

				ret = wret;



			if (path->nodes[0] == leaf &&

			    btrfs_header_nritems(leaf)) {

				wret = push_leaf_left(trans, root, path, 1);

				wret = push_leaf_left(trans, root, path, 1, 1);

				if (wret < 0 && wret != -ENOSPC)

					ret = wret;

			}