Merge tag 'f2fs-for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs update from Jaegeuk Kim:
 "In this round, we've mainly focused on performance tuning and critical
  bug fixes occurred in low-end devices. Sheng Yong introduced
  lost_found feature to keep missing files during recovery instead of
  thrashing them. We're preparing coming fsverity implementation. And,
  we've got more features to communicate with users for better
  performance. In low-end devices, some memory-related issues were
  fixed, and subtle race condtions and corner cases were addressed as
  well.

  Enhancements:
   - large nat bitmaps for more free node ids
   - add three block allocation policies to pass down write hints given by user
   - expose extension list to user and introduce hot file extension
   - tune small devices seamlessly for low-end devices
   - set readdir_ra by default
   - give more resources under gc_urgent mode regarding to discard and cleaning
   - introduce fsync_mode to enforce posix or not
   - nowait aio support
   - add lost_found feature to keep dangling inodes
   - reserve bits for future fsverity feature
   - add test_dummy_encryption for FBE

  Bug fixes:
   - don't use highmem for dentry pages
   - align memory boundary for bitops
   - truncate preallocated blocks in write errors
   - guarantee i_times on fsync call
   - clear CP_TRIMMED_FLAG correctly
   - prevent node chain loop during recovery
   - avoid data race between atomic write and background cleaning
   - avoid unnecessary selinux violation warnings on resgid option
   - GFP_NOFS to avoid deadlock in quota and read paths
   - fix f2fs_skip_inode_update to allow i_size recovery

  In addition to the above, there are several minor bug fixes and clean-ups"

* tag 'f2fs-for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (50 commits)
  f2fs: remain written times to update inode during fsync
  f2fs: make assignment of t->dentry_bitmap more readable
  f2fs: truncate preallocated blocks in error case
  f2fs: fix a wrong condition in f2fs_skip_inode_update
  f2fs: reserve bits for fs-verity
  f2fs: Add a segment type check in inplace write
  f2fs: no need to initialize zero value for GFP_F2FS_ZERO
  f2fs: don't track new nat entry in nat set
  f2fs: clean up with F2FS_BLK_ALIGN
  f2fs: check blkaddr more accuratly before issue a bio
  f2fs: Set GF_NOFS in read_cache_page_gfp while doing f2fs_quota_read
  f2fs: introduce a new mount option test_dummy_encryption
  f2fs: introduce F2FS_FEATURE_LOST_FOUND feature
  f2fs: release locks before return in f2fs_ioc_gc_range()
  f2fs: align memory boundary for bitops
  f2fs: remove unneeded set_cold_node()
  f2fs: add nowait aio support
  f2fs: wrap all options with f2fs_sb_info.mount_opt
  f2fs: Don't overwrite all types of node to keep node chain
  f2fs: introduce mount option for fsync mode
  ...

1 files changed, 77 insertions, 0 deletions

diff --git a/Documentation/filesystems/f2fs.txt b/Documentation/filesystems/f2fs.txt
index 13c2ff034348..12a147c9f87f 100644
--- a/Documentation/filesystems/f2fs.txt
+++ b/Documentation/filesystems/f2fs.txt
@@ -174,6 +174,23 @@ offgrpjquota           Turn off group journelled quota.
 offprjjquota           Turn off project journelled quota.
 quota                  Enable plain user disk quota accounting.
 noquota                Disable all plain disk quota option.
+whint_mode=%s          Control which write hints are passed down to block
+                       layer. This supports "off", "user-based", and
+                       "fs-based".  In "off" mode (default), f2fs does not pass
+                       down hints. In "user-based" mode, f2fs tries to pass
+                       down hints given by users. And in "fs-based" mode, f2fs
+                       passes down hints with its policy.
+alloc_mode=%s          Adjust block allocation policy, which supports "reuse"
+                       and "default".
+fsync_mode=%s          Control the policy of fsync. Currently supports "posix"
+                       and "strict". In "posix" mode, which is default, fsync
+                       will follow POSIX semantics and does a light operation
+                       to improve the filesystem performance. In "strict" mode,
+                       fsync will be heavy and behaves in line with xfs, ext4
+                       and btrfs, where xfstest generic/342 will pass, but the
+                       performance will regress.
+test_dummy_encryption  Enable dummy encryption, which provides a fake fscrypt
+                       context. The fake fscrypt context is used by xfstests.
 
 ================================================================================
 DEBUGFS ENTRIES
@@ -611,3 +628,63 @@ algorithm.
 In order to identify whether the data in the victim segment are valid or not,
 F2FS manages a bitmap. Each bit represents the validity of a block, and the
 bitmap is composed of a bit stream covering whole blocks in main area.
+
+Write-hint Policy
+-----------------
+
+1) whint_mode=off. F2FS only passes down WRITE_LIFE_NOT_SET.
+
+2) whint_mode=user-based. F2FS tries to pass down hints given by
+users.
+
+User                  F2FS                     Block
+----                  ----                     -----
+                      META                     WRITE_LIFE_NOT_SET
+                      HOT_NODE                 "
+                      WARM_NODE                "
+                      COLD_NODE                "
+*ioctl(COLD)          COLD_DATA                WRITE_LIFE_EXTREME
+*extension list       "                        "
+
+-- buffered io
+WRITE_LIFE_EXTREME    COLD_DATA                WRITE_LIFE_EXTREME
+WRITE_LIFE_SHORT      HOT_DATA                 WRITE_LIFE_SHORT
+WRITE_LIFE_NOT_SET    WARM_DATA                WRITE_LIFE_NOT_SET
+WRITE_LIFE_NONE       "                        "
+WRITE_LIFE_MEDIUM     "                        "
+WRITE_LIFE_LONG       "                        "
+
+-- direct io
+WRITE_LIFE_EXTREME    COLD_DATA                WRITE_LIFE_EXTREME
+WRITE_LIFE_SHORT      HOT_DATA                 WRITE_LIFE_SHORT
+WRITE_LIFE_NOT_SET    WARM_DATA                WRITE_LIFE_NOT_SET
+WRITE_LIFE_NONE       "                        WRITE_LIFE_NONE
+WRITE_LIFE_MEDIUM     "                        WRITE_LIFE_MEDIUM
+WRITE_LIFE_LONG       "                        WRITE_LIFE_LONG
+
+3) whint_mode=fs-based. F2FS passes down hints with its policy.
+
+User                  F2FS                     Block
+----                  ----                     -----
+                      META                     WRITE_LIFE_MEDIUM;
+                      HOT_NODE                 WRITE_LIFE_NOT_SET
+                      WARM_NODE                "
+                      COLD_NODE                WRITE_LIFE_NONE
+ioctl(COLD)           COLD_DATA                WRITE_LIFE_EXTREME
+extension list        "                        "
+
+-- buffered io
+WRITE_LIFE_EXTREME    COLD_DATA                WRITE_LIFE_EXTREME
+WRITE_LIFE_SHORT      HOT_DATA                 WRITE_LIFE_SHORT
+WRITE_LIFE_NOT_SET    WARM_DATA                WRITE_LIFE_LONG
+WRITE_LIFE_NONE       "                        "
+WRITE_LIFE_MEDIUM     "                        "
+WRITE_LIFE_LONG       "                        "
+
+-- direct io
+WRITE_LIFE_EXTREME    COLD_DATA                WRITE_LIFE_EXTREME
+WRITE_LIFE_SHORT      HOT_DATA                 WRITE_LIFE_SHORT
+WRITE_LIFE_NOT_SET    WARM_DATA                WRITE_LIFE_NOT_SET
+WRITE_LIFE_NONE       "                        WRITE_LIFE_NONE
+WRITE_LIFE_MEDIUM     "                        WRITE_LIFE_MEDIUM
+WRITE_LIFE_LONG       "                        WRITE_LIFE_LONG