torture: copychunk test suite improvements
Allow for large files in test_setup_copy_chunk():
Write test data in 1M IOs, rather than attempting to do the whole
thing in one go.
Add copychunk bad resume key test:
Send a copy chunk request with an intentionally bogus resume key
(source key handle).
Add copychunk src=dest test:
Test copychunk requests where the source and destination handles refer
to the same file.
Add copychunk src=dest overlap test.
Add desired access args to test_setup_copy_chunk().
Add copychunk_bad_access test:
Open the copychunk source and destination files with differing
desired_access values. Confirm copychunk response matches 2k8 and 2k12
behaviour.
Add copy_chunk_src_exceed test:
Attempts to copy more data than is present in the copychunk source
file.
Add copy_chunk_src_exceed_multi test:
Test whether the first chunk in a multi-chunk copychunk request is
written to disk, where the second chunk is invalid due to src file
overrun.
Add copy_chunk_sparse_dest test:
Issue a request where the target offset exceeds the file size, resulting
in a sparse region.
Add copy_chunk_max_output_sz test.
Reviewed by: Jeremy Allison <jra@samba.org>