New code for 5.12: - Fix an ABBA deadlock when renaming files on overlayfs. - Make sure that we can't overflow the inode extent counters when adding to or removing extents from a file. - Make directory sgid inheritance work the same way as all the other filesystems. - Don't drain the buffer cache on freeze and ro remount, which should reduce the amount of time if read-only workloads are continuing during the freeze. - Fix a bug where symlink size isn't reported to the vfs in ecryptfs. - Disentangle log cleaning from log covering. This refactoring sets us up for future changes to the log, though for now it simply means that we can use covering for freezes, and cleaning becomes something we only do at unmount. - Speed up file fsyncs by reducing iolock cycling.