97d0bf96a0
Pull btrfs updates from David Sterba:
"User visible changes:
- new block group profiles: RAID1 with 3- and 4- copies
- RAID1 in btrfs has always 2 copies, now add support for 3 and 4
- this is an incompat feature (named RAID1C34)
- recommended use of RAID1C3 is replacement of RAID6 profile on
metadata, this brings a more reliable resiliency against 2
device loss/damage
- support for new checksums
- per-filesystem, set at mkfs time
- fast hash (crc32c successor): xxhash, 64bit digest
- strong hashes (both 256bit): sha256 (slower, FIPS), blake2b
(faster)
- the blake2b module goes via the crypto tree, btrfs.ko has a
soft dependency
- speed up lseek, don't take inode locks unnecessarily, this can
speed up parallel SEEK_CUR/SEEK_SET/SEEK_END by 80%
- send:
- allow clone operations within the same file
- limit maximum number of sent clone references to avoid slow
backref walking
- error message improvements: device scan prints process name and PID
Core changes:
- cleanups
- remove unique workqueue helpers, used to provide a way to avoid
deadlocks in the workqueue code, now done in a simpler way
- remove lots of indirect function calls in compression code
- extent IO tree code moved out of extent_io.c
- cleanup backup superblock handling at mount time
- transaction life cycle documentation and cleanups
- locking code cleanups, annotations and documentation
- add more cold, const, pure function attributes
- removal of unused or redundant struct members or variables
- new tree-checker sanity tests
- try to detect missing INODE_ITEM, cross-reference checks of
DIR_ITEM, DIR_INDEX, INODE_REF, and XATTR_* items
- remove own bio scheduling code (used to avoid checksum submissions
being stuck behind other IO), replaced by cgroup controller-based
code to allow better control and avoid priority inversions in cases
where the custom and cgroup scheduling disagreed
Fixes:
- avoid getting stuck during cyclic writebacks
- fix trimming of ranges crossing block group boundaries
- fix rename exchange on subvolumes, all involved subvolumes need to
be recorded in the transaction"
* tag 'for-5.5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (137 commits)
btrfs: drop bdev argument from submit_extent_page
btrfs: remove extent_map::bdev
btrfs: drop bio_set_dev where not needed
btrfs: get bdev directly from fs_devices in submit_extent_page
btrfs: record all roots for rename exchange on a subvol
Btrfs: fix block group remaining RO forever after error during device replace
btrfs: scrub: Don't check free space before marking a block group RO
btrfs: change btrfs_fs_devices::rotating to bool
btrfs: change btrfs_fs_devices::seeding to bool
btrfs: rename btrfs_block_group_cache
btrfs: block-group: Reuse the item key from caller of read_one_block_group()
btrfs: block-group: Refactor btrfs_read_block_groups()
btrfs: document extent buffer locking
btrfs: access eb::blocking_writers according to ACCESS_ONCE policies
btrfs: set blocking_writers directly, no increment or decrement
btrfs: merge blocking_writers branches in btrfs_tree_read_lock
btrfs: drop incompat bit for raid1c34 after last block group is gone
btrfs: add incompat for raid1 with 3, 4 copies
btrfs: add support for 4-copy replication (raid1c4)
btrfs: add support for 3-copy replication (raid1c3)
...
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