Copyable file descriptor.

A unit of work to be scheduled by TaskMaster.

A lot of Unix API wants you to initialize a struct and call one function to fill it, another function to throw it away, and has some unknown third thi

Barrier delays the execution of one or more Tasks. The Tasks are executed when the last shared reference to the BarrierState is released. Copies of B

Scan the extent tree and submit each extent's references in a single batch.

Scan each subvol in round-robin with no synchronization. Good for continuous forward progress while avoiding lock contention.

Scan the same inode/offset tuple in each subvol. Good for caching and space saving, bad for filesystems with rotating snapshots.

Scan the most recently completely scanned subvols first. Keeps recently added data from accumulating in small subvols while large subvols are still u

Scan each subvol completely, in numerical order, before moving on to the next. This was an experimental mode that requires large amounts of temporary

C++ threads dumbed down even further

Fetch data extent items from extent tree, skipping metadata-only block groups

Fetch extent refs from an inode. Caller must set the tree and objectid.

Fetch extent items from extent tree. Does not filter out metadata! See BtrfsDataExtentTreeFetcher for that.

Fetch raw inode items

Fetch a root (subvol) item

FIXME: ExtentCursor is probably a better name

like unique_lock but for flock instead of mutexes...and not trying to hide the many and subtle differences between those two things *at all*.

File descriptor owner object. It closes them when destroyed. Most of the functions here don't use it because these functions don't own FDs. All good