Merge remote-tracking branch 'origin/upstream-f2fs-stable-linux-4.9.y' into android-4.9

* origin/upstream-f2fs-stable-linux-4.9.y:
  f2fs: use EINVAL for superblock with invalid magic
  f2fs: fix to read source block before invalidating it
  f2fs: remove redundant check from f2fs_setflags_common()
  f2fs: use generic checking and prep function for FS_IOC_SETFLAGS
  vfs: use READ_ONCE() to access ->i_link
  fs, fscrypt: clear DCACHE_ENCRYPTED_NAME when unaliasing directory
  fscrypt: cache decrypted symlink target in ->i_link
  fscrypt: fix race where ->lookup() marks plaintext dentry as ciphertext
  ext4: remove unused d_name argument from ext4_search_dir() et al.
  fscrypt: only set dentry_operations on ciphertext dentries
  fscrypt: fix race allowing rename() and link() of ciphertext dentries
  fscrypt: clean up and improve dentry revalidation
  fscrypt: use READ_ONCE() to access ->i_crypt_info
  fscrypt: remove WARN_ON_ONCE() when decryption fails
  fscrypt: drop inode argument from fscrypt_get_ctx()
  f2fs: improve print log in f2fs_sanity_check_ckpt()
  f2fs: avoid out-of-range memory access
  f2fs: fix to avoid long latency during umount
  f2fs: allow all the users to pin a file
  f2fs: support swap file w/ DIO
  f2fs: allocate blocks for pinned file
  f2fs: fix is_idle() check for discard type
  f2fs: add a rw_sem to cover quota flag changes
  f2fs: set SBI_NEED_FSCK for xattr corruption case
  f2fs: use generic EFSBADCRC/EFSCORRUPTED
  f2fs: Use DIV_ROUND_UP() instead of open-coding
  f2fs: print kernel message if filesystem is inconsistent
  f2fs: introduce f2fs_<level> macros to wrap f2fs_printk()
  f2fs: avoid get_valid_blocks() for cleanup
  f2fs: ioctl for removing a range from F2FS
  f2fs: only set project inherit bit for directory
  f2fs: separate f2fs i_flags from fs_flags and ext4 i_flags
  f2fs: Add option to limit required GC for checkpoint=disable
  f2fs: Fix accounting for unusable blocks
  f2fs: Fix root reserved on remount
  f2fs: Lower threshold for disable_cp_again
  f2fs: fix sparse warning
  f2fs: fix f2fs_show_options to show nodiscard mount option
  f2fs: add error prints for debugging mount failure
  f2fs: fix to do sanity check on segment bitmap of LFS curseg
  f2fs: add missing sysfs entries in documentation
  f2fs: fix to avoid deadloop if data_flush is on
  f2fs: always assume that the device is idle under gc_urgent
  f2fs: add bio cache for IPU
  f2fs: allow ssr block allocation during checkpoint=disable period
  f2fs: fix to check layout on last valid checkpoint park

Change-Id: I7ec07950386e32e3955b6a8192804b7d3174fd18
Signed-off-by: Jaegeuk Kim <jaegeuk@google.com>