/usr/bin/btrfsck

usage: btrfs check [options] <device>

Check structural integrity of a filesystem (unmounted).

  Check structural integrity of an unmounted filesystem. Verify internal
  trees' consistency and item connectivity. In the repair mode try to
  fix the problems found.
  WARNING: the repair mode is considered dangerous and should not be used
           without prior analysis of problems found on the filesystem.

Starting point selection:
-s, --super NUMBER        use this superblock copy
-b, --backup              use the first valid backup root copy
-r, --tree-root           use the given bytenr for the tree root
--chunk-root BYTENR       use the given bytenr for the chunk tree root

Operation modes:
--readonly                run in read-only mode (default)
--repair                  try to repair the filesystem (dangerous, see above warning)
--force                   skip mount checks, recommended only with --readonly; WARNING: it is possible to run with
                          --repair but on a mounted filesystem that will most likely lead to a corruption unless the
                          filesystem is quiescent in a quiescent state which may not be possible to guarantee
--mode MODE               allows choice of memory/IO trade-offs where MODE is one of:
                          original - read inodes and extents to memory (requires more memory, does less IO)
                          lowmem - try to use less memory but read blocks again when needed

Repair options:
--init-csum-tree          create a new CRC tree
--init-extent-tree        create a new extent tree

Check and reporting options:
--check-data-csum         verify checksums of data blocks
--skip-qgroup-accounting  skip quota group accounting verification
-Q, --qgroup-report       print a report on qgroup consistency
-E, --subvol-extents SUBVOLID
                          print subvolume extents and sharing state
-p, --progress            indicate progress

Deprecated or moved options:
--clear-space-cache v1|v2 clear space cache for v1 or v2 (moved to 'rescue' group)