More usage options for testing open_by_handle, which are needed
for testing stable handles across copy up in overlayfs.
usage: open_by_handle [-c|-l|-u|-d] <test_dir> [num_files]
Examples:
1. Create test set of N files and try to get their NFS handles:
open_by_handle -c <test_dir> [N]
This is used by new helper _require_exportfs() to check
if filesystem supports exportfs
2. Get file handles for existing test set, drop caches and try to
open all files by handle:
open_by_handle <test_dir> [N]
3. Get file handles for existing test set, unlink all test files,
drop caches, try to open all files by handle and expect ESTALE:
open_by_handle -d <test_dir> [N]
4. Get file handles for existing test set, hardlink all test files,
then unlink the original files, drop caches and try to open all
files by handle (should work):
open_by_handle -l <test_dir> [N]
open_by_handle -u <test_dir> [N]
This test is done with 2 invocations of the program, first to
hardlink (-l) and then to unlink the originals (-u), because
we would like to be able to perform the hardlinks on overlay
lower layer and unlink on upper layer.
NOTE that open_by_handle -u doesn't check if the files are
hardlinked, it just assumes that they are. If they are not
then the test will fail, because file handles would be stale.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>
Amir Goldstein
5210726732