New code for 5.13: - Various minor fixes in online scrub. - Prevent metadata files from being automatically inactivated. - Validate btree heights by the computed per-btree limits. - Don't warn about remounting with deprecated mount options. - Initialize attr forks at create time if we suspect we're going to need to store them. - Reduce memory reallocation workouts in the logging code. - Fix some theoretical math calculation errors in logged buffers that span multiple discontig memory ranges but contiguous ondisk regions. - Speedups in dirty buffer bitmap handling. - Make type verifier functions more inline-happy to reduce overhead. - Reduce debug overhead in directory checking code. - Many many typo fixes. - Begin to handle the permanent loss of the very end of a filesystem.