[PATCH v3 00/14] forcealign for xfs

John Garry
2024-08-01T16:31:55Z

This series is being spun off the block atomic writes for xfs series at
[0].

That series got too big.

The actual forcealign patches are roughly the same in this series.

Why forcealign?
In some scenarios to may be required to guarantee extent alignment and
granularity.

For example, for atomic writes, the maximum atomic write unit size would
be limited at the extent alignment and granularity, guaranteeing that an
atomic write would not span data present in multiple extents.

forcealign may be useful as a performance tuning optimization in other
scenarios.

I decided not to support forcealign for RT devices here. Initially I
thought that it would be quite simple of implement. However, I recently
discovered through much testing and subsequent debug that this was not
true, so I decided to defer support to later.

Early development xfsprogs support is at:
https://github.com/johnpgarry/xfsprogs-dev/commits/atomic-writes/

Differences to v2:
- Add rounding to alloc unit helpers
- Update xfs_setattr_size()
- Disallow mount for forcealign and reflink
- Remove forcealign and RT/reflink inode checks
- Relocate setting of XFS_ALLOC_FORCEALIGN

Differences to v1:
- Add Darricks RB tags (thanks)
- Disallow mount for forcealign and RT
- Disallow cp --reflink from forcealign inode
- Comments improvements (Darrick)
- Coding style improvements (Darrick)
- Fix xfs_inode_alloc_unitsize() (Darrick)

Baseline:
v6.11-rc1

[0] https://lore.kernel.org/linux-xfs/20240607143919.2622319-1-john.g.garry@oracle.com/
[1] https://lore.kernel.org/linux-block/20240620125359.2684798-1-john.g.garry@oracle.com/

Darrick J. Wong (2):
xfs: Introduce FORCEALIGN inode flag
xfs: Enable file data forcealign feature

Dave Chinner (6):
xfs: only allow minlen allocations when near ENOSPC
xfs: always tail align maxlen allocations
xfs: simplify extent allocation alignment
xfs: make EOF allocation simpler
xfs: introduce forced allocation alignment
xfs: align args->minlen for forced allocation alignment

John Garry (6):
xfs: Update xfs_inode_alloc_unitsize() for forcealign
xfs: Update xfs_setattr_size() for forcealign
xfs: Do not free EOF blocks for forcealign
xfs: Only free full extents for forcealign
xfs: Unmap blocks according to forcealign
xfs: Don't revert allocated offset for forcealign

fs/xfs/libxfs/xfs_alloc.c | 33 ++--
fs/xfs/libxfs/xfs_alloc.h | 3 +-
fs/xfs/libxfs/xfs_bmap.c | 322 ++++++++++++++++++---------------
fs/xfs/libxfs/xfs_format.h | 9 +-
fs/xfs/libxfs/xfs_ialloc.c | 12 +-
fs/xfs/libxfs/xfs_inode_buf.c | 46 +++++
fs/xfs/libxfs/xfs_inode_buf.h | 3 +
fs/xfs/libxfs/xfs_inode_util.c | 14 ++
fs/xfs/libxfs/xfs_sb.c | 2 +
fs/xfs/xfs_bmap_util.c | 14 +-
fs/xfs/xfs_inode.c | 61 ++++++-
fs/xfs/xfs_inode.h | 18 ++
fs/xfs/xfs_ioctl.c | 46 ++++-
fs/xfs/xfs_iops.c | 4 +-
fs/xfs/xfs_mount.h | 2 +
fs/xfs/xfs_reflink.c | 5 +-
fs/xfs/xfs_super.c | 18 ++
fs/xfs/xfs_trace.h | 8 +-
include/uapi/linux/fs.h | 2 +
19 files changed, 431 insertions(+), 191 deletions(-)

--
2.31.1