f2fs-for-5.14-rc1 In this round, we've improved the compression support especially for Android such as allowing compression for mmap files, replacing the immutable bit with internal bit to prohibits data writes explicitly, and adding a mount option, "compress_cache", to improve random reads. And, we added "readonly" feature to compact the partition w/ compression enabled, which will be useful for Android RO partitions. Enhancement: - support compression for mmap file - use an f2fs flag instead of IMMUTABLE bit for compression - support RO feature w/ extent_cache - fully support swapfile with file pinning - improve atgc tunability - add nocompress extensions to unselect files for compression Bug fix: - fix false alaram on iget failure during GC - fix race condition on global pointers when there are multiple f2fs instances - add MODULE_SOFTDEP for initramfs As usual, we've also cleaned up some places for better code readability. (e.g., sysfs/feature, debugging messages, slab cache name, and docs)