Merge tag 'f2fs-for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've tuned f2fs to improve general performance by
  serializing block allocation and enhancing discard flows like fstrim
  which avoids user IO contention. And we've added fsync_mode=nobarrier
  which gives an option to user where it skips issuing cache_flush
  commands to underlying flash storage. And there are many bug fixes
  related to fuzzed images, revoked atomic writes, quota ops, and minor
  direct IO.

  Enhancements:
   - add fsync_mode=nobarrier which bypasses cache_flush command
   - enhance the discarding flow which avoids user IOs and issues in
     LBA order
   - readahead some encrypted blocks during GC
   - enable in-memory inode checksum to verify the blocks if
     F2FS_CHECK_FS is set
   - enhance nat_bits behavior
   - set -o discard by default
   - set REQ_RAHEAD to bio in ->readpages

  Bug fixes:
   - fix a corner case to corrupt atomic_writes revoking flow
   - revisit i_gc_rwsem to fix race conditions
   - fix some dio behaviors captured by xfstests
   - correct handling errors given by quota-related failures
   - add many sanity check flows to avoid fuzz test failures
   - add more error number propagation to their callers
   - fix several corner cases to continue fault injection w/ shutdown
     loop"

* tag 'f2fs-for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (89 commits)
  f2fs: readahead encrypted block during GC
  f2fs: avoid fi->i_gc_rwsem[WRITE] lock in f2fs_gc
  f2fs: fix performance issue observed with multi-thread sequential read
  f2fs: fix to skip verifying block address for non-regular inode
  f2fs: rework fault injection handling to avoid a warning
  f2fs: support fault_type mount option
  f2fs: fix to return success when trimming meta area
  f2fs: fix use-after-free of dicard command entry
  f2fs: support discard submission error injection
  f2fs: split discard command in prior to block layer
  f2fs: wake up gc thread immediately when gc_urgent is set
  f2fs: fix incorrect range->len in f2fs_trim_fs()
  f2fs: refresh recent accessed nat entry in lru list
  f2fs: fix avoid race between truncate and background GC
  f2fs: avoid race between zero_range and background GC
  f2fs: fix to do sanity check with block address in main area v2
  f2fs: fix to do sanity check with inline flags
  f2fs: fix to reset i_gc_failures correctly
  f2fs: fix invalid memory access
  f2fs: fix to avoid broken of dnode block list
  ...

Author: torvalds

Documentation/ABI/testing/sysfs-fs-f2fs

@@ -51,6 +51,14 @@ Description:
 		 Controls the dirty page count condition for the in-place-update
 		 policies.
 
+What:		/sys/fs/f2fs/<disk>/min_seq_blocks
+Date:		August 2018
+Contact:	"Jaegeuk Kim" <[email protected]>
+Description:
+		 Controls the dirty page count condition for batched sequential
+		 writes in ->writepages.
+
+
 What:		/sys/fs/f2fs/<disk>/min_hot_blocks
 Date:		March 2017
 Contact:	"Jaegeuk Kim" <[email protected]>

Documentation/filesystems/f2fs.txt

@@ -157,6 +157,24 @@ data_flush             Enable data flushing before checkpoint in order to
                        persist data of regular and symlink.
 fault_injection=%d     Enable fault injection in all supported types with
                        specified injection rate.
+fault_type=%d          Support configuring fault injection type, should be
+                       enabled with fault_injection option, fault type value
+                       is shown below, it supports single or combined type.
+                       Type_Name		Type_Value
+                       FAULT_KMALLOC		0x000000001
+                       FAULT_KVMALLOC		0x000000002
+                       FAULT_PAGE_ALLOC		0x000000004
+                       FAULT_PAGE_GET		0x000000008
+                       FAULT_ALLOC_BIO		0x000000010
+                       FAULT_ALLOC_NID		0x000000020
+                       FAULT_ORPHAN		0x000000040
+                       FAULT_BLOCK		0x000000080
+                       FAULT_DIR_DEPTH		0x000000100
+                       FAULT_EVICT_INODE	0x000000200
+                       FAULT_TRUNCATE		0x000000400
+                       FAULT_IO			0x000000800
+                       FAULT_CHECKPOINT		0x000001000
+                       FAULT_DISCARD		0x000002000
 mode=%s                Control block allocation mode which supports "adaptive"
                        and "lfs". In "lfs" mode, there should be no random
                        writes towards main area.