Merge remote-tracking branch 'origin/upstream-f2fs-stable-linux-4.4.y' into android-4.4

* origin/upstream-f2fs-stable-linux-4.4.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
  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: I12033b777edf57fb337c13df82caec464f1426d6
Signed-off-by: Jaegeuk Kim <jaegeuk@google.com>

2 files changed, 131 insertions, 10 deletions

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
index e916c1eddf1b..4c7324524b0f 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -243,3 +243,11 @@ Description:
 		 - Del: echo '[h/c]!extension' > /sys/fs/f2fs/<disk>/extension_list
 		 - [h] means add/del hot file extension
 		 - [c] means add/del cold file extension
+
+What:		/sys/fs/f2fs/<disk>/unusable
+Date		April 2019
+Contact:	"Daniel Rosenberg" <drosen@google.com>
+Description:
+		If checkpoint=disable, it displays the number of blocks that are unusable.
+                If checkpoint=enable it displays the enumber of blocks that would be unusable
+                if checkpoint=disable were to be set.
diff --git a/Documentation/filesystems/f2fs.txt b/Documentation/filesystems/f2fs.txt
index 564ccc6c7bad..c2e941317b87 100644
--- a/Documentation/filesystems/f2fs.txt
+++ b/Documentation/filesystems/f2fs.txt
@@ -214,11 +214,22 @@ fsync_mode=%s          Control the policy of fsync. Currently supports "posix",
                        non-atomic files likewise "nobarrier" mount option.
 test_dummy_encryption  Enable dummy encryption, which provides a fake fscrypt
                        context. The fake fscrypt context is used by xfstests.
-checkpoint=%s          Set to "disable" to turn off checkpointing. Set to "enable"
+checkpoint=%s[:%u[%]]     Set to "disable" to turn off checkpointing. Set to "enable"
                        to reenable checkpointing. Is enabled by default. While
                        disabled, any unmounting or unexpected shutdowns will cause
                        the filesystem contents to appear as they did when the
                        filesystem was mounted with that option.
+                       While mounting with checkpoint=disabled, the filesystem must
+                       run garbage collection to ensure that all available space can
+                       be used. If this takes too much time, the mount may return
+                       EAGAIN. You may optionally add a value to indicate how much
+                       of the disk you would be willing to temporarily give up to
+                       avoid additional garbage collection. This can be given as a
+                       number of blocks, or as a percent. For instance, mounting
+                       with checkpoint=disable:100% would always succeed, but it may
+                       hide up to all remaining free space. The actual space that
+                       would be unusable can be viewed at /sys/fs/f2fs/<disk>/unusable
+                       This space is reclaimed once checkpoint=enable.
 
 ================================================================================
 DEBUGFS ENTRIES
@@ -246,11 +257,14 @@ Files in /sys/fs/f2fs/<devname>
 ..............................................................................
  File                         Content
 
- gc_max_sleep_time            This tuning parameter controls the maximum sleep
+ gc_urgent_sleep_time         This parameter controls sleep time for gc_urgent.
+                              500 ms is set by default. See above gc_urgent.
+
+ gc_min_sleep_time            This tuning parameter controls the minimum sleep
                               time for the garbage collection thread. Time is
                               in milliseconds.
 
- gc_min_sleep_time            This tuning parameter controls the minimum sleep
+ gc_max_sleep_time            This tuning parameter controls the maximum sleep
                               time for the garbage collection thread. Time is
                               in milliseconds.
 
@@ -270,9 +284,6 @@ Files in /sys/fs/f2fs/<devname>
                               to 1, background thread starts to do GC by given
                               gc_urgent_sleep_time interval.
 
- gc_urgent_sleep_time         This parameter controls sleep time for gc_urgent.
-                              500 ms is set by default. See above gc_urgent.
-
  reclaim_segments             This parameter controls the number of prefree
                               segments to be reclaimed. If the number of prefree
 			      segments is larger than the number of segments
@@ -287,7 +298,16 @@ Files in /sys/fs/f2fs/<devname>
 			      checkpoint is triggered, and issued during the
 			      checkpoint. By default, it is disabled with 0.
 
- trim_sections                This parameter controls the number of sections
+ discard_granularity	      This parameter controls the granularity of discard
+			      command size. It will issue discard commands iif
+			      the size is larger than given granularity. Its
+			      unit size is 4KB, and 4 (=16KB) is set by default.
+			      The maximum value is 128 (=512KB).
+
+ reserved_blocks	      This parameter indicates the number of blocks that
+			      f2fs reserves internally for root.
+
+ batched_trim_sections	      This parameter controls the number of sections
                               to be trimmed out in batch mode when FITRIM
                               conducts. 32 sections is set by default.
 
@@ -309,11 +329,35 @@ Files in /sys/fs/f2fs/<devname>
 			      the number is less than this value, it triggers
 			      in-place-updates.
 
+ min_seq_blocks		      This parameter controls the threshold to serialize
+			      write IOs issued by multiple threads in parallel.
+
+ min_hot_blocks		      This parameter controls the threshold to allocate
+			      a hot data log for pending data blocks to write.
+
+ min_ssr_sections	      This parameter adds the threshold when deciding
+			      SSR block allocation. If this is large, SSR mode
+			      will be enabled early.
+
+ ram_thresh                   This parameter controls the memory footprint used
+			      by free nids and cached nat entries. By default,
+			      10 is set, which indicates 10 MB / 1 GB RAM.
+
+ ra_nid_pages		      When building free nids, F2FS reads NAT blocks
+			      ahead for speed up. Default is 0.
+
+ dirty_nats_ratio	      Given dirty ratio of cached nat entries, F2FS
+			      determines flushing them in background.
+
  max_victim_search	      This parameter controls the number of trials to
 			      find a victim segment when conducting SSR and
 			      cleaning operations. The default value is 4096
 			      which covers 8GB block address range.
 
+ migration_granularity	      For large-sized sections, F2FS can stop GC given
+			      this granularity instead of reclaiming entire
+			      section.
+
  dir_level                    This parameter controls the directory level to
 			      support large directory. If a directory has a
 			      number of files, it can reduce the file lookup
@@ -321,9 +365,53 @@ Files in /sys/fs/f2fs/<devname>
 			      Otherwise, it needs to decrease this value to
 			      reduce the space overhead. The default value is 0.
 
- ram_thresh                   This parameter controls the memory footprint used
-			      by free nids and cached nat entries. By default,
-			      10 is set, which indicates 10 MB / 1 GB RAM.
+ cp_interval		      F2FS tries to do checkpoint periodically, 60 secs
+			      by default.
+
+ idle_interval		      F2FS detects system is idle, if there's no F2FS
+			      operations during given interval, 5 secs by
+			      default.
+
+ discard_idle_interval	      F2FS detects the discard thread is idle, given
+			      time interval. Default is 5 secs.
+
+ gc_idle_interval	      F2FS detects the GC thread is idle, given time
+			      interval. Default is 5 secs.
+
+ umount_discard_timeout       When unmounting the disk, F2FS waits for finishing
+			      queued discard commands which can take huge time.
+			      This gives time out for it, 5 secs by default.
+
+ iostat_enable		      This controls to enable/disable iostat in F2FS.
+
+ readdir_ra		      This enables/disabled readahead of inode blocks
+			      in readdir, and default is enabled.
+
+ gc_pin_file_thresh	      This indicates how many GC can be failed for the
+			      pinned file. If it exceeds this, F2FS doesn't
+			      guarantee its pinning state. 2048 trials is set
+			      by default.
+
+ extension_list		      This enables to change extension_list for hot/cold
+			      files in runtime.
+
+ inject_rate		      This controls injection rate of arbitrary faults.
+
+ inject_type		      This controls injection type of arbitrary faults.
+
+ dirty_segments 	      This shows # of dirty segments.
+
+ lifetime_write_kbytes	      This shows # of data written to the disk.
+
+ features		      This shows current features enabled on F2FS.
+
+ current_reserved_blocks      This shows # of blocks currently reserved.
+
+ unusable                     If checkpoint=disable, this shows the number of
+                              blocks that are unusable.
+                              If checkpoint=enable it shows the number of blocks
+                              that would be unusable if checkpoint=disable were
+                              to be set.
 
 ================================================================================
 USAGE
@@ -656,3 +744,28 @@ 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.
+
+Fallocate(2) Policy
+-------------------
+
+The default policy follows the below posix rule.
+
+Allocating disk space
+    The default operation (i.e., mode is zero) of fallocate() allocates
+    the disk space within the range specified by offset and len.  The
+    file size (as reported by stat(2)) will be changed if offset+len is
+    greater than the file size.  Any subregion within the range specified
+    by offset and len that did not contain data before the call will be
+    initialized to zero.  This default behavior closely resembles the
+    behavior of the posix_fallocate(3) library function, and is intended
+    as a method of optimally implementing that function.
+
+However, once F2FS receives ioctl(fd, F2FS_IOC_SET_PIN_FILE) in prior to
+fallocate(fd, DEFAULT_MODE), it allocates on-disk blocks addressess having
+zero or random data, which is useful to the below scenario where:
+ 1. create(fd)
+ 2. ioctl(fd, F2FS_IOC_SET_PIN_FILE)
+ 3. fallocate(fd, 0, 0, size)
+ 4. address = fibmap(fd, offset)
+ 5. open(blkdev)
+ 6. write(blkdev, address)