Pull f2fs updates from Jaegeuk Kim:
"Major changes are to:
- add f2fs_io_tracer and F2FS_IOC_GETVERSION
- fix wrong acl assignment from parent
- fix accessing wrong data blocks
- fix wrong condition check for f2fs_sync_fs
- align start block address for direct_io
- add and refactor the readahead flows of FS metadata
- refactor atomic and volatile write policies
But most of patches are for clean-ups and minor bug fixes. Some of
them refactor old code too"
* tag 'for-f2fs-3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (64 commits)
f2fs: use spinlock for segmap_lock instead of rwlock
f2fs: fix accessing wrong indexed data blocks
f2fs: avoid variable length array
f2fs: fix sparse warnings
f2fs: allocate data blocks in advance for f2fs_direct_IO
f2fs: introduce macros to convert bytes and blocks in f2fs
f2fs: call set_buffer_new for get_block
f2fs: check node page contents all the time
f2fs: avoid data offset overflow when lseeking huge file
f2fs: fix to use highmem for pages of newly created directory
f2fs: introduce a batched trim
f2fs: merge {invalidate,release}page for meta/node/data pages
f2fs: show the number of writeback pages in stat
f2fs: keep PagePrivate during releasepage
f2fs: should fail mount when trying to recover data on read-only dev
f2fs: split UMOUNT and FASTBOOT flags
f2fs: avoid write_checkpoint if f2fs is mounted readonly
f2fs: support norecovery mount option
f2fs: fix not to drop mount options when retrying fill_super
f2fs: merge flags in struct f2fs_sb_info
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