This patchset add support for adding new checksum types in BTRFS.
Currently BTRFS only supports CRC32C as data and metadata checksum, which is
good if you only want to detect errors due to data corruption in hardware.
But CRC32C isn't able cover other use-cases like de-duplication or
cryptographically save data integrity guarantees.
The following properties made SHA-256 interesting for these use-cases:
- Still considered cryptographically sound
- Reasonably well understood by the security industry
- Result fits into the 32Byte/256Bit we have for the checksum in the on-disk
format
- Small enough collision space to make it feasible for data de-duplication
- Fast enough to calculate and offloadable to crypto hardware via the kernel's
crypto_shash framework.
The patchset also provides mechanisms for plumbing in different hash
algorithms relatively easy.
Unfortunately this patchset also partially reverts commit:
9678c54388b6 ("btrfs: Remove custom crc32c init code")
Patches 1 - 16 are preparation patches to make the change of the checksum
algorithm easy and patch 17 then finally adds SHA-256 as a new checksum
algorithm.
Only patch 17/17 is dependent on mkfs changes.
Johannes Thumshirn (17):
btrfs: use btrfs_csum_data() instead of directly calling crc32c
btrfs: resurrect btrfs_crc32c()
btrfs: use btrfs_crc32c() instead of btrfs_extref_hash()
btrfs: use btrfs_crc32c() instead of btrfs_name_hash()
btrfs: don't assume ordered sums to be 4 bytes
btrfs: dont assume compressed_bio sums to be 4 bytes
btrfs: use btrfs_crc32c{,_final}() in for free space cache
btrfs: format checksums according to type for printing
btrfs: add common checksum type validation
btrfs: check for supported superblock checksum type before checksum
validation
btrfs: Simplify btrfs_check_super_csum() and get rid of size
assumptions
btrfs: add boilerplate code for directly including the crypto
framework
btrfs: pass in an fs_info to btrfs_csum_{data,final}()
btrfs: directly call into crypto framework for checsumming
btrfs: remove assumption about csum type form
btrfs_csum_{data,final}()
btrfs: remove assumption about csum type form
btrfs_print_data_csum_error()
btrfs: add sha256 as another checksum algorithm
fs/btrfs/btrfs_inode.h | 33 ++++++--
fs/btrfs/check-integrity.c | 6 +-
fs/btrfs/compression.c | 34 +++++----
fs/btrfs/compression.h | 2 +-
fs/btrfs/ctree.h | 30 +++++---
fs/btrfs/dir-item.c | 10 +--
fs/btrfs/disk-io.c | 164 +++++++++++++++++++++++++++++-----------
fs/btrfs/disk-io.h | 5 +-
fs/btrfs/extent-tree.c | 6 +-
fs/btrfs/file-item.c | 35 ++++-----
fs/btrfs/free-space-cache.c | 10 +--
fs/btrfs/inode-item.c | 6 +-
fs/btrfs/inode.c | 21 +++--
fs/btrfs/ordered-data.c | 13 ++--
fs/btrfs/ordered-data.h | 4 +-
fs/btrfs/props.c | 5 +-
fs/btrfs/scrub.c | 22 +++---
fs/btrfs/send.c | 5 +-
fs/btrfs/tree-checker.c | 3 +-
fs/btrfs/tree-log.c | 6 +-
include/uapi/linux/btrfs_tree.h | 1 +
21 files changed, 276 insertions(+), 145 deletions(-)
--
2.16.4
