Merge branch 'for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "There are some new user features and the usual load of invisible
  enhancements or cleanups.

  New features:

   - extend mount options to specify zlib compression level, -o
     compress=zlib:9

   - v2 of ioctl "extent to inode mapping", addressing a usecase where
     we want to retrieve more but inaccurate results and do the
     postprocessing in userspace, aiding defragmentation or
     deduplication tools

   - populate compression heuristics logic, do data sampling and try to
     guess compressibility by: looking for repeated patterns, counting
     unique byte values and distribution, calculating Shannon entropy;
     this will need more benchmarking and possibly fine tuning, but the
     base should be good enough

   - enable indexing for btrfs as lower filesystem in overlayfs

   - speedup page cache readahead during send on large files

  Internal enhancements:

   - more sanity checks of b-tree items when reading them from disk

   - more EINVAL/EUCLEAN fixups, missing BLK_STS_* conversion, other
     errno or error handling fixes

   - remove some homegrown IO-related logic, that's been obsoleted by
     core block layer changes (batching, plug/unplug, own counters)

   - add ref-verify, optional debugging feature to verify extent
     reference accounting

   - simplify code handling outstanding extents, make it more clear
     where and how the accounting is done

   - make delalloc reservations per-inode, simplify the code and make
     the logic more straightforward

   - extensive cleanup of delayed refs code

  Notable fixes:

   - fix send ioctl on 32bit with 64bit kernel"

* 'for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (102 commits)
  btrfs: Fix bug for misused dev_t when lookup in dev state hash table.
  Btrfs: heuristic: add Shannon entropy calculation
  Btrfs: heuristic: add byte core set calculation
  Btrfs: heuristic: add byte set calculation
  Btrfs: heuristic: add detection of repeated data patterns
  Btrfs: heuristic: implement sampling logic
  Btrfs: heuristic: add bucket and sample counters and other defines
  Btrfs: compression: separate heuristic/compression workspaces
  btrfs: move btrfs_truncate_block out of trans handle
  btrfs: don't call btrfs_start_delalloc_roots in flushoncommit
  btrfs: track refs in a rb_tree instead of a list
  btrfs: add a comp_refs() helper
  btrfs: switch args for comp_*_refs
  btrfs: make the delalloc block rsv per inode
  btrfs: add tracepoints for outstanding extents mods
  Btrfs: rework outstanding_extents
  btrfs: increase output size for LOGICAL_INO_V2 ioctl
  btrfs: add a flags argument to LOGICAL_INO and call it LOGICAL_INO_V2
  btrfs: add a flag to iterate_inodes_from_logical to find all extent refs for uncompressed extents
  btrfs: send: remove unused code
  ...

1 files changed, 14 insertions, 1 deletions

diff --git a/fs/btrfs/zlib.c b/fs/btrfs/zlib.c
index c248f9286366..2b52950dc2c6 100644
--- a/fs/btrfs/zlib.c
+++ b/fs/btrfs/zlib.c
@@ -37,6 +37,7 @@ struct workspace {
 	z_stream strm;
 	char *buf;
 	struct list_head list;
+	int level;
 };
 
 static void zlib_free_workspace(struct list_head *ws)
@@ -96,7 +97,7 @@ static int zlib_compress_pages(struct list_head *ws,
 	*total_out = 0;
 	*total_in = 0;
 
-	if (Z_OK != zlib_deflateInit(&workspace->strm, 3)) {
+	if (Z_OK != zlib_deflateInit(&workspace->strm, workspace->level)) {
 		pr_warn("BTRFS: deflateInit failed\n");
 		ret = -EIO;
 		goto out;
@@ -402,10 +403,22 @@ next:
 	return ret;
 }
 
+static void zlib_set_level(struct list_head *ws, unsigned int type)
+{
+	struct workspace *workspace = list_entry(ws, struct workspace, list);
+	unsigned level = (type & 0xF0) >> 4;
+
+	if (level > 9)
+		level = 9;
+
+	workspace->level = level > 0 ? level : 3;
+}
+
 const struct btrfs_compress_op btrfs_zlib_compress = {
 	.alloc_workspace	= zlib_alloc_workspace,
 	.free_workspace		= zlib_free_workspace,
 	.compress_pages		= zlib_compress_pages,
 	.decompress_bio		= zlib_decompress_bio,
 	.decompress		= zlib_decompress,
+	.set_level              = zlib_set_level,
 };