31  * Initialize the extent tree @tree.  Should be called for each new inode or
72 /* Do the math around the end of an extent, handling wrapping. */
170 	 * Previous extent map found, return as in this case the caller does not  in tree_search()
238 	 * extent maps of 2 (or more) adjacent extents merged, so factor it out.  in mergeable_maps()
254  * @prev:    left extent to merge
255  * @next:    right extent to merge
256  * @merged:  the extent we will not discard after the merge; updated with new values
258  * After this, one of the two extents is the new merged extent and the other is
263  * For now only uncompressed regular extent can be merged.
279 	 * 1) They are referring to the same data extent:  in merge_ondisk_extents()
281 	 * |<----- data extent A ----->|  in merge_ondisk_extents()
286 	 * |<-- data extent A -->|<-- data extent B -->|  in merge_ondisk_extents()
292 	 * For case 1), the merged data extent would be the same.  in merge_ondisk_extents()
361 	 * We can't modify an extent map that is in the tree and that is being  in try_merge_map()
364 	 * the tree and 1 for this task (which is unpinning the extent map or  in try_merge_map()
409  * Unpin an extent from the cache.
411  * @inode:	the inode from which we are unpinning an extent range
413  * @len:	length of the extent
414  * @gen:	generation that this extent has been modified in
416  * Called after an extent has been written to disk properly.  Set the generation
418  * we need to sync this extent when we call fsync().
421  * 	    -ENOENT  when the extent is not found in the tree
422  * 	    -EUCLEAN if the found extent does not match the expected start
436 "no extent map found for inode %llu (root %lld) when unpinning extent range [%llu, %llu), generatio…  in btrfs_unpin_extent_cache()
445 "found extent map for inode %llu (root %lld) with unexpected start offset %llu when unpinning exten…  in btrfs_unpin_extent_cache()
488  * Add a new extent map to an inode's extent map tree.
493  *	        modified list, which indicates the extent needs to be logged
495  * Insert @em into the @inode's extent map tree or perform a simple
567  * Find a nearby extent map intersecting @start + @len (not an exact search).
576  * If one can't be found, any nearby extent may be returned
585  * Remove an extent_map from its inode's extent tree.
587  * @inode:	the inode the extent map belongs to
588  * @em:		extent map being removed
590  * Remove @em from the extent tree of @inode.  No reference counts are dropped,
649  * Helper for btrfs_get_extent.  Given an existing extent in the tree,
650  * the existing extent is the nearest extent to map_start,
651  * and an extent that you want to insert, deal with overlap and insert
652  * the best fitted new extent into the tree.
689  * Add extent mapping into an inode's extent map tree.
692  * @em_in:    extent we are inserting
699  * Insert @em_in into the inode's extent map tree. In case there is an
701  * a) Returning the existing extent in @em_in if @start is within the
703  * b) Merge the existing extent with @em_in passed in.
716 	 * Tree-checker should have rejected any inline extent with non-zero  in btrfs_add_extent_mapping()
723 	/* it is possible that someone inserted the extent into the tree  in btrfs_add_extent_mapping()
736 		 * extent causing the -EEXIST.  in btrfs_add_extent_mapping()
748 			 * The existing extent map is the one nearest to  in btrfs_add_extent_mapping()
756 "extent map merge error existing [%llu, %llu) with em [%llu, %llu) start %llu",  in btrfs_add_extent_mapping()
769  * Drop all extent maps from a tree in the fastest possible way, rescheduling
771  * extent map, before each deletion.
798  * Drop all extent maps in a given range.
803  * @skip_pinned: Indicate if pinned extent maps should be ignored or not.
805  * This drops all the extent maps that intersect the given range [@start, @end].
806  * Extent maps that partially overlap the range and extend behind or beyond it,
833 	 * It's ok if we fail to allocate the extent maps, see the comment near  in btrfs_drop_extent_map_range()
834 	 * the bottom of the loop below. We only need two spare extent maps in  in btrfs_drop_extent_map_range()
835 	 * the worst case, where the first extent map that intersects our range  in btrfs_drop_extent_map_range()
836 	 * starts before the range and the last extent map that intersects our  in btrfs_drop_extent_map_range()
837 	 * range ends after our range (and they might be the same extent map),  in btrfs_drop_extent_map_range()
838 	 * because we need to split those two extent maps at the boundaries.  in btrfs_drop_extent_map_range()
871 		 * In case we split the extent map, we want to preserve the  in btrfs_drop_extent_map_range()
872 		 * EXTENT_FLAG_LOGGING flag on our extent map, but we don't want  in btrfs_drop_extent_map_range()
873 		 * it on the new extent maps.  in btrfs_drop_extent_map_range()
879 		 * The extent map does not cross our target range, so no need to  in btrfs_drop_extent_map_range()
956 			 * If the extent map is still in the tree it means that  in btrfs_drop_extent_map_range()
963 			 *    range, and we were not able to allocate the extent  in btrfs_drop_extent_map_range()
967 			 * extent map - this is fine since if anyone needs it to  in btrfs_drop_extent_map_range()
969 			 * load it again from the subvolume tree's file extent  in btrfs_drop_extent_map_range()
970 			 * item. However if the extent map was in the list of  in btrfs_drop_extent_map_range()
973 			 * extent if it's new and needs to be logged.  in btrfs_drop_extent_map_range()
984 		 * extent map from the tree).  in btrfs_drop_extent_map_range()
1001  * Replace a range in the inode's extent map tree with a new extent map.
1004  * @new_em:     The new extent map to add to the inode's extent map tree.
1005  * @modified:   Indicate if the new extent map should be added to the list of
1008  * Drops all the extent maps in the inode's extent map tree that intersect the
1009  * range of the new extent map and adds the new extent map to the tree.
1025 	 * tree, but getting -EEXIST when adding the new extent map can still  in btrfs_replace_extent_map_range()
1027 	 * this is due to two tasks operating on different parts of the extent.  in btrfs_replace_extent_map_range()
1147 	 * in case we have to remove extent maps in the tree's list of modified  in btrfs_scan_inode()
1156 	 * we are holding the extent map tree's lock in write mode.  in btrfs_scan_inode()
1231 		 * Skip inode if it doesn't have loaded extent maps, so we avoid  in find_first_inode_to_shrink()
1234 		 * files with all extent maps previously released through the  in find_first_inode_to_shrink()
1236 		 * a previous run, or directories which never have extent maps.  in find_first_inode_to_shrink()
1375 	 * nr_to_scan extent maps (or less). In case we need to free more than  in btrfs_free_extent_maps()
1377 	 * not doing enough work to reclaim memory from extent maps.  in btrfs_free_extent_maps()