Commit 009b2056 authored by David Sterba's avatar David Sterba
Browse files

btrfs: defrag: add flag to force no-compression 



Currently the defrag ioctl cannot rewrite the extents without
compression. Add a new flag for that, as setting compression to 0 (or
"no compression") means to do no changes to compression so take what is
the current default, like mount options or properties.

The defrag setting overrides mount or properties. The compression
BTRFS_DEFRAG_DONT_COMPRESS is only used for in-memory operations and
does not need to have a fixed value.

Mount with zstd:9, copy test file from /usr/bin/ (about 260KB):

  $ mount -o compress=zstd:9 /dev/vda /mnt
  $ filefrag -vsb testfile
  filefrag: -b needs a blocksize option, assuming 1024-byte blocks.
  Filesystem type is: 9123683e
  File size of testfile is 297704 (292 blocks of 1024 bytes)
   ext:     logical_offset:        physical_offset: length:   expected: flags:
     0:        0..     127:      13312..     13439:    128:             encoded
     1:      128..     255:      13364..     13491:    128:      13440: encoded
     2:      256..     291:      13424..     13459:     36:      13492: last,encoded,eof
  testfile: 3 extents found

  $ compsize testfile
  Processed 1 file, 3 regular extents (3 refs), 0 inline, 1 fragments.
  Type       Perc     Disk Usage   Uncompressed Referenced
  TOTAL       42%      124K         292K         292K
  zstd        42%      124K         292K         292K

Defrag to uncompressed:

  $ btrfs fi defrag --nocomp testfile
  $ filefrag -vsb testfile
  filefrag: -b needs a blocksize option, assuming 1024-byte blocks.
  Filesystem type is: 9123683e
  File size of testfile is 297704 (292 blocks of 1024 bytes)
   ext:     logical_offset:        physical_offset: length:   expected: flags:
     0:        0..     291:     291840..    292131:    292:             last,eof
  testfile: 1 extent found

  $ compsize testfile
  Processed 1 file, 1 regular extents (1 refs), 0 inline, 1 fragments.
  Type       Perc     Disk Usage   Uncompressed Referenced
  TOTAL      100%      292K         292K         292K
  none       100%      292K         292K         292K

Compress again with LZO:

  $ btrfs fi defrag -clzo testfile
  $ filefrag -vsb testfile
  filefrag: -b needs a blocksize option, assuming 1024-byte blocks.
  Filesystem type is: 9123683e
  File size of testfile is 297704 (292 blocks of 1024 bytes)
   ext:     logical_offset:        physical_offset: length:   expected: flags:
     0:        0..     127:      13312..     13439:    128:             encoded
     1:      128..     255:      13392..     13519:    128:      13440: encoded
     2:      256..     291:      13480..     13515:     36:      13520: last,encoded,eof
  testfile: 3 extents found

  $ compsize testfile
  Processed 1 file, 3 regular extents (3 refs), 0 inline, 1 fragments.
  Type       Perc     Disk Usage   Uncompressed Referenced
  TOTAL       64%      188K         292K         292K
  lzo         64%      188K         292K         292K

Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 807d9023

fs/btrfs/compression.h

+2 −0
Original line number Diff line number Diff line
@@ -113,6 +113,8 @@ enum btrfs_compression_type { 
	BTRFS_COMPRESS_LZO   = 2,

	BTRFS_COMPRESS_ZSTD  = 3,

	BTRFS_NR_COMPRESS_TYPES = 4,



	BTRFS_DEFRAG_DONT_COMPRESS,

};



struct workspace_manager {

fs/btrfs/defrag.c

+9 −4
Original line number Diff line number Diff line
@@ -947,7 +947,7 @@ struct defrag_target_range { 
 * @extent_thresh: file extent size threshold, any extent size >= this value

 *		   will be ignored

 * @newer_than:    only defrag extents newer than this value

 * @do_compress:   whether the defrag is doing compression

 * @do_compress:   whether the defrag is doing compression or no-compression

 *		   if true, @extent_thresh will be ignored and all regular

 *		   file extents meeting @newer_than will be targets.

 * @locked:	   if the range has already held extent lock
@@ -1364,6 +1364,7 @@ int btrfs_defrag_file(struct btrfs_inode *inode, struct file_ra_state *ra, 
	u64 cur;

	u64 last_byte;

	bool do_compress = (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS);

	bool no_compress = (range->flags & BTRFS_DEFRAG_RANGE_NOCOMPRESS);

	int compress_type = BTRFS_COMPRESS_ZLIB;

	int compress_level = 0;

	int ret = 0;
@@ -1394,6 +1395,9 @@ int btrfs_defrag_file(struct btrfs_inode *inode, struct file_ra_state *ra, 
			if (range->compress_type)

				compress_type = range->compress_type;

		}

	} else if (range->flags & BTRFS_DEFRAG_RANGE_NOCOMPRESS) {

		compress_type = BTRFS_DEFRAG_DONT_COMPRESS;

		compress_level = 1;

	}



	if (extent_thresh == 0)
@@ -1444,13 +1448,14 @@ int btrfs_defrag_file(struct btrfs_inode *inode, struct file_ra_state *ra, 
			btrfs_inode_unlock(inode, 0);

			break;

		}

		if (do_compress) {

		if (do_compress || no_compress) {

			inode->defrag_compress = compress_type;

			inode->defrag_compress_level = compress_level;

		}

		ret = defrag_one_cluster(inode, ra, cur,

				cluster_end + 1 - cur, extent_thresh,

				newer_than, do_compress, &sectors_defragged,

				newer_than, do_compress || no_compress,

				&sectors_defragged,

				max_to_defrag, &last_scanned);



		if (sectors_defragged > prev_sectors_defragged)
@@ -1489,7 +1494,7 @@ int btrfs_defrag_file(struct btrfs_inode *inode, struct file_ra_state *ra, 
			btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);

		ret = sectors_defragged;

	}

	if (do_compress) {

	if (do_compress || no_compress) {

		btrfs_inode_lock(inode, 0);

		inode->defrag_compress = BTRFS_COMPRESS_NONE;

		btrfs_inode_unlock(inode, 0);

fs/btrfs/inode.c

+7 −4
Original line number Diff line number Diff line
@@ -781,12 +781,15 @@ static inline int inode_need_compress(struct btrfs_inode *inode, u64 start, 
		return 0;

	}



	/* Defrag ioctl takes precedence over mount options and properties. */

	if (inode->defrag_compress == BTRFS_DEFRAG_DONT_COMPRESS)

		return 0;

	if (BTRFS_COMPRESS_NONE < inode->defrag_compress &&

	    inode->defrag_compress < BTRFS_NR_COMPRESS_TYPES)

		return 1;

	/* force compress */

	if (btrfs_test_opt(fs_info, FORCE_COMPRESS))

		return 1;

	/* defrag ioctl */

	if (inode->defrag_compress)

		return 1;

	/* bad compression ratios */

	if (inode->flags & BTRFS_INODE_NOCOMPRESS)

		return 0;
@@ -942,7 +945,7 @@ static void compress_file_range(struct btrfs_work *work) 
		goto cleanup_and_bail_uncompressed;

	}



	if (inode->defrag_compress) {

	if (0 < inode->defrag_compress && inode->defrag_compress < BTRFS_NR_COMPRESS_TYPES) {

		compress_type = inode->defrag_compress;

		compress_level = inode->defrag_compress_level;

	} else if (inode->prop_compress) {

fs/btrfs/ioctl.c

+8 −2
Original line number Diff line number Diff line
@@ -2554,8 +2554,14 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp) 
				ret = -EOPNOTSUPP;

				goto out;

			}

			/* compression requires us to start the IO */

			if ((range.flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {

			if ((range.flags & BTRFS_DEFRAG_RANGE_COMPRESS) &&

			    (range.flags & BTRFS_DEFRAG_RANGE_NOCOMPRESS)) {

				ret = -EINVAL;

				goto out;

			}

			/* Compression or no-compression require to start the IO. */

			if ((range.flags & BTRFS_DEFRAG_RANGE_COMPRESS) ||

			    (range.flags & BTRFS_DEFRAG_RANGE_NOCOMPRESS)) {

				range.flags |= BTRFS_DEFRAG_RANGE_START_IO;

				range.extent_thresh = (u32)-1;

			}

include/uapi/linux/btrfs.h

+3 −0
Original line number Diff line number Diff line
@@ -616,8 +616,11 @@ struct btrfs_ioctl_clone_range_args { 
#define BTRFS_DEFRAG_RANGE_COMPRESS 1

#define BTRFS_DEFRAG_RANGE_START_IO 2

#define BTRFS_DEFRAG_RANGE_COMPRESS_LEVEL 4

/* Request no compression on the range (uncompress if necessary). */

#define BTRFS_DEFRAG_RANGE_NOCOMPRESS	8

#define BTRFS_DEFRAG_RANGE_FLAGS_SUPP	(BTRFS_DEFRAG_RANGE_COMPRESS |		\

					 BTRFS_DEFRAG_RANGE_COMPRESS_LEVEL |	\

					 BTRFS_DEFRAG_RANGE_NOCOMPRESS |	\

					 BTRFS_DEFRAG_RANGE_START_IO)



struct btrfs_ioctl_defrag_range_args {