Changes since last update:
- More metadata validation strengthening to prevent crashes.
- Fix extent offset overflow problem when insert_range on a 512b block fs
- Fix some off-by-one errors in the realtime fsmap code
- Fix some math errors in the default resblks calculation when free space
  is low
- Fix a problem where stale page contents are exposed via mmap read
  after a zero_range at eof
- Fix accounting problems with per-ag reservations causing statfs
  reports to vary incorrectly
xfs: fix fdblocks accounting w/ RMAPBT per-AG reservation

In __xfs_ag_resv_init we incorrectly calculate the amount by which to
decrease fdblocks when reserving blocks for the rmapbt.  Because rmapbt
allocations do not decrease fdblocks, we must decrease fdblocks by the
entire size of the requested reservation in order to achieve our goal of
always having enough free blocks to satisfy an rmapbt expansion.

This is in contrast to the refcountbt/finobt, which /do/ subtract from
fdblocks whenever they allocate a block.  For this allocation type we
preserve the existing behavior where we decrease fdblocks only by the
requested reservation minus the size of the existing tree.

This fixes the problem where the available block counts reported by
statfs change across a remount if there had been an rmapbt size change
since mount time.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
1 file changed