static int init_child(struct dm_btree_info *info, struct dm_btree_value_type *vt,
		      struct btree_node *parent,
		      unsigned index, struct child *result)
{
	int r, inc;
	dm_block_t root;

	result->index = index;
	root = value64(parent, index);

	r = dm_tm_shadow_block(info->tm, root, &btree_node_validator,
			       &result->block, &inc);
	if (r)
		return r;

	result->n = dm_block_data(result->block);

	if (inc)
		inc_children(info->tm, result->n, vt);

	*((__le64 *) value_ptr(parent, index)) =
		cpu_to_le64(dm_block_location(result->block));

	return 0;
}
Exemple #2
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static int bn_shadow(struct dm_btree_info *info, dm_block_t orig,
	      struct dm_btree_value_type *vt,
	      struct dm_block **result)
{
	int r, inc;

	r = dm_tm_shadow_block(info->tm, orig, &btree_node_validator,
			       result, &inc);
	if (!r && inc)
		inc_children(info->tm, dm_block_data(*result), vt);

	return r;
}
Exemple #3
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/*
 * Looks up an array block in the btree.  Then shadows it, and updates the
 * btree to point to this new shadow.  'root' is an input/output parameter
 * for both the current root block, and the new one.
 */
static int shadow_ablock(struct dm_array_info *info, dm_block_t *root,
			 unsigned index, struct dm_block **block,
			 struct array_block **ab)
{
	int r, inc;
	uint64_t key = index;
	dm_block_t b;
	__le64 block_le;

	/*
	 * lookup
	 */
	r = dm_btree_lookup(&info->btree_info, *root, &key, &block_le);
	if (r)
		return r;
	b = le64_to_cpu(block_le);

	/*
	 * shadow
	 */
	r = dm_tm_shadow_block(info->btree_info.tm, b,
			       &array_validator, block, &inc);
	if (r)
		return r;

	*ab = dm_block_data(*block);
	if (inc)
		inc_ablock_entries(info, *ab);

	/*
	 * Reinsert.
	 *
	 * The shadow op will often be a noop.  Only insert if it really
	 * copied data.
	 */
	if (dm_block_location(*block) != b) {
		/*
		 * dm_tm_shadow_block will have already decremented the old
		 * block, but it is still referenced by the btree.  We
		 * increment to stop the insert decrementing it below zero
		 * when overwriting the old value.
		 */
		dm_tm_inc(info->btree_info.tm, b);
		r = insert_ablock(info, index, *block, root);
	}

	return r;
}
Exemple #4
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/*
 * Looks up an array block in the btree.  Then shadows it, and updates the
 * btree to point to this new shadow.  'root' is an input/output parameter
 * for both the current root block, and the new one.
 */
static int shadow_ablock(struct dm_array_info *info, dm_block_t *root,
			 unsigned index, struct dm_block **block,
			 struct array_block **ab)
{
	int r, inc;
	uint64_t key = index;
	dm_block_t b;
	__le64 block_le;

	/*
	 * lookup
	 */
	r = dm_btree_lookup(&info->btree_info, *root, &key, &block_le);
	if (r)
		return r;
	b = le64_to_cpu(block_le);

	/*
	 * shadow
	 */
	r = dm_tm_shadow_block(info->btree_info.tm, b,
			       &array_validator, block, &inc);
	if (r)
		return r;

	*ab = dm_block_data(*block);
	if (inc)
		inc_ablock_entries(info, *ab);

	/*
	 * Reinsert.
	 *
	 * The shadow op will often be a noop.  Only insert if it really
	 * copied data.
	 */
	if (dm_block_location(*block) != b)
		r = insert_ablock(info, index, *block, root);

	return r;
}