/*
* Utility function to look for merge candidates inside a given range.
* Any extents with matching state are merged together into a single
* extent in the tree. Extents with EXTENT_IO in their state field are
* not merged
*/
static int merge_state(struct extent_io_tree *tree,
struct extent_state *state)
{
struct extent_state *other;
struct cache_extent *other_node;
if (state->state & EXTENT_IOBITS)
return 0;
other_node = prev_cache_extent(&state->cache_node);
if (other_node) {
other = container_of(other_node, struct extent_state,
cache_node);
if (other->end == state->start - 1 &&
other->state == state->state) {
state->start = other->start;
update_extent_state(state);
remove_cache_extent(&tree->state, &other->cache_node);
btrfs_free_extent_state(other);
}
}
other_node = next_cache_extent(&state->cache_node);
if (other_node) {
other = container_of(other_node, struct extent_state,
cache_node);
if (other->start == state->end + 1 &&
other->state == state->state) {
other->start = state->start;
update_extent_state(other);
remove_cache_extent(&tree->state, &state->cache_node);
btrfs_free_extent_state(state);
}
}
return 0;
}
void extent_io_tree_cleanup(struct extent_io_tree *tree)
{
struct extent_state *es;
struct extent_buffer *eb;
struct cache_extent *cache;
while(!list_empty(&tree->lru)) {
eb = list_entry(tree->lru.next, struct extent_buffer, lru);
if (eb->refs != 1) {
fprintf(stderr, "extent buffer leak: "
"start %llu len %u\n",
(unsigned long long)eb->start, eb->len);
eb->refs = 1;
}
free_extent_buffer(eb);
}
while (1) {
cache = find_first_cache_extent(&tree->state, 0);
if (!cache)
break;
es = container_of(cache, struct extent_state, cache_node);
remove_cache_extent(&tree->state, &es->cache_node);
free_extent_state(es);
}
}
/*
* clear some bits on a range in the tree.
*/
static int clear_state_bit(struct extent_io_tree *tree,
struct extent_state *state, int bits)
{
int ret = state->state & bits;
state->state &= ~bits;
if (state->state == 0) {
remove_cache_extent(&tree->state, &state->cache_node);
btrfs_free_extent_state(state);
} else {
merge_state(tree, state);
}
return ret;
}
static int free_fs_roots(struct btrfs_fs_info *fs_info)
{
struct cache_extent *cache;
struct btrfs_root *root;
while (1) {
cache = find_first_cache_extent(&fs_info->fs_root_cache, 0);
if (!cache)
break;
root = container_of(cache, struct btrfs_root, cache);
remove_cache_extent(&fs_info->fs_root_cache, cache);
btrfs_free_fs_root(fs_info, root);
}
return 0;
}
