Merge tag 'for-f2fs-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "Most part of the patches include enhancing the stability and
  performance of in-memory extent caches feature.

  In addition, it introduces several new features and configurable
  points:
   - F2FS_GOING_DOWN_METAFLUSH ioctl to test power failures
   - F2FS_IOC_WRITE_CHECKPOINT ioctl to trigger checkpoint by users
   - background_gc=sync mount option to do gc synchronously
   - periodic checkpoints
   - sysfs entry to control readahead blocks for free nids

  And the following bug fixes have been merged.
   - fix SSA corruption by collapse/insert_range
   - correct a couple of gc behaviors
   - fix the results of f2fs_map_blocks
   - fix error case handling of volatile/atomic writes"

* tag 'for-f2fs-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (54 commits)
  f2fs: fix to skip shrinking extent nodes
  f2fs: fix error path of ->symlink
  f2fs: fix to clear GCed flag for atomic written page
  f2fs: don't need to submit bio on error case
  f2fs: fix leakage of inmemory atomic pages
  f2fs: refactor __find_rev_next_{zero}_bit
  f2fs: support fiemap for inline_data
  f2fs: flush dirty data for bmap
  f2fs: relocate the tracepoint for background_gc
  f2fs crypto: fix racing of accessing encrypted page among
  f2fs: export ra_nid_pages to sysfs
  f2fs: readahead for free nids building
  f2fs: support lower priority asynchronous readahead in ra_meta_pages
  f2fs: don't tag REQ_META for temporary non-meta pages
  f2fs: add a tracepoint for f2fs_read_data_pages
  f2fs: set GFP_NOFS for grab_cache_page
  f2fs: fix SSA updates resulting in corruption
  Revert "f2fs: do not skip dentry block writes"
  f2fs: add F2FS_GOING_DOWN_METAFLUSH to test power-failure
  f2fs: merge meta writes as many possible
  ...