diff options
| -rw-r--r-- | ctree.c | 24 | ||||
| -rw-r--r-- | ctree.h | 2 | ||||
| -rw-r--r-- | extent-tree.c | 63 |
3 files changed, 89 insertions, 0 deletions
@@ -2951,3 +2951,27 @@ int btrfs_previous_extent_item(struct btrfs_root *root, } return 1; } + +/* + * Search in extent tree to found next meta/data extent + * Caller needs to check for no-hole or skinny metadata features. + */ +int btrfs_next_extent_item(struct btrfs_root *root, + struct btrfs_path *path, u64 max_objectid) +{ + struct btrfs_key found_key; + int ret; + + while (1) { + ret = btrfs_next_item(root, path); + if (ret) + return ret; + btrfs_item_key_to_cpu(path->nodes[0], &found_key, + path->slots[0]); + if (found_key.objectid > max_objectid) + return 1; + if (found_key.type == BTRFS_EXTENT_ITEM_KEY || + found_key.type == BTRFS_METADATA_ITEM_KEY) + return 0; + } +} @@ -2388,6 +2388,8 @@ int btrfs_previous_item(struct btrfs_root *root, int type); int btrfs_previous_extent_item(struct btrfs_root *root, struct btrfs_path *path, u64 min_objectid); +int btrfs_next_extent_item(struct btrfs_root *root, + struct btrfs_path *path, u64 max_objectid); int btrfs_cow_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct extent_buffer *buf, struct extent_buffer *parent, int parent_slot, diff --git a/extent-tree.c b/extent-tree.c index 4a41717e..6ccd4245 100644 --- a/extent-tree.c +++ b/extent-tree.c @@ -3909,6 +3909,69 @@ int btrfs_fix_block_accounting(struct btrfs_trans_handle *trans, return 0; } +static void __get_extent_size(struct btrfs_root *root, struct btrfs_path *path, + u64 *start, u64 *len) +{ + struct btrfs_key key; + + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + BUG_ON(!(key.type == BTRFS_EXTENT_ITEM_KEY || + key.type == BTRFS_METADATA_ITEM_KEY)); + *start = key.objectid; + if (key.type == BTRFS_EXTENT_ITEM_KEY) + *len = key.offset; + else + *len = root->nodesize; +} + +/* + * Find first overlap extent for range [bytenr, bytenr + len) + * Return 0 for found and point path to it. + * Return >0 for not found. + * Return <0 for err + */ +int btrfs_search_overlap_extent(struct btrfs_root *root, + struct btrfs_path *path, u64 bytenr, u64 len) +{ + struct btrfs_key key; + u64 cur_start; + u64 cur_len; + int ret; + + key.objectid = bytenr; + key.type = BTRFS_EXTENT_DATA_KEY; + key.offset = (u64)-1; + + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + return ret; + BUG_ON(ret == 0); + + ret = btrfs_previous_extent_item(root, path, 0); + if (ret < 0) + return ret; + /* no previous, check next extent */ + if (ret > 0) + goto next; + __get_extent_size(root, path, &cur_start, &cur_len); + /* Tail overlap */ + if (cur_start + cur_len > bytenr) + return 1; + +next: + ret = btrfs_next_extent_item(root, path, bytenr + len); + if (ret < 0) + return ret; + /* No next, prev already checked, no overlap */ + if (ret > 0) + return 0; + __get_extent_size(root, path, &cur_start, &cur_len); + /* head overlap*/ + if (cur_start < bytenr + len) + return 1; + return 0; +} + /* * Record a file extent. Do all the required works, such as inserting * file extent item, inserting extent item and backref item into extent |