generic: add write vs fcollapse test
This test exposed a problem with XFS where it failed to write back a
partial page correctly during a fcollapse operation. This left a
stray dirty buffer on the page, and hence invalidation of the page
then failed of the fcollapse returned an EBUSY error.
Make this a generic test so that we can ensure that all filesystems
handle the case correctly. Test case originally worked out and
written by Brian Foster.
Signed-off-by: Dave Chinner <email@example.com>
3 files changed