Pull ext4 updates from Ted Ts'o:

 - Replace ext4's bmap and iopoll implementations to use iomap.

 - Clean up extent tree handling.

 - Other cleanups and miscellaneous bug fixes

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (31 commits)
  ext4: save all error info in save_error_info() and drop ext4_set_errno()
  ext4: fix incorrect group count in ext4_fill_super error message
  ext4: fix incorrect inodes per group in error message
  ext4: don't set dioread_nolock by default for blocksize < pagesize
  ext4: disable dioread_nolock whenever delayed allocation is disabled
  ext4: do not commit super on read-only bdev
  ext4: avoid ENOSPC when avoiding to reuse recently deleted inodes
  ext4: unregister sysfs path before destroying jbd2 journal
  ext4: check for non-zero journal inum in ext4_calculate_overhead
  ext4: remove map_from_cluster from ext4_ext_map_blocks
  ext4: clean up ext4_ext_insert_extent() call in ext4_ext_map_blocks()
  ext4: mark block bitmap corrupted when found instead of BUGON
  ext4: use flexible-array member for xattr structs
  ext4: use flexible-array member in struct fname
  Documentation: correct the description of FIEMAP_EXTENT_LAST
  ext4: move ext4_fiemap to use iomap framework
  ext4: make ext4_ind_map_blocks work with fiemap
  ext4: move ext4 bmap to use iomap infrastructure
  ext4: optimize ext4_ext_precache for 0 depth
  ext4: add IOMAP_F_MERGED for non-extent based mapping
  ...