[PATCH pynfs 01/13] server41tests: add helpers and basic synchronous COPY test

[Jeff Layton <jlayton@kernel.org>]

Add helpers to reduce boilerplate in COPY tests: _do_copy(),
_create_and_open(), _poll_offload_status(), and chunked _write_data()/
_verify_data() that split I/O into pieces bounded by the session's
negotiated ca_maxrequestsize/ca_maxresponsesize (a single large WRITE or
READ would otherwise fail with NFS4ERR_REQ_TOO_BIG).

Add testSyncCopy (COPY1): write 64KB to a source file, copy it, and
verify the destination contents.  RFC 7862 permits a server to perform
the copy asynchronously even when a synchronous copy is requested, so
honor cr_resok4.cr_requirements.cr_synchronous: poll OFFLOAD_STATUS to
completion when the server downgrades to async instead of failing on a
zero wr_count.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 nfs4.1/server41tests/st_copy.py | 90 ++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 89 insertions(+), 1 deletion(-)

diff --git a/nfs4.1/server41tests/st_copy.py b/nfs4.1/server41tests/st_copy.py
index a4bdb77ca407..c7e48adf6fbe 100644
--- a/nfs4.1/server41tests/st_copy.py
+++ b/nfs4.1/server41tests/st_copy.py
@@ -1,14 +1,102 @@
+import time
+
 from .st_create_session import create_session
 from xdrdef.nfs4_const import *
 
 from .environment import check, fail, create_file, open_file, close_file
-from .environment import open_create_file_op, use_obj, write_file
+from .environment import open_create_file_op, use_obj, write_file, read_file
 from xdrdef.nfs4_type import open_owner4, openflag4, createhow4, open_claim4
 from xdrdef.nfs4_type import creatverfattr, fattr4, stateid4, locker4, lock_owner4
 from xdrdef.nfs4_type import open_to_lock_owner4
 import nfs_ops
 op = nfs_ops.NFS4ops()
 
+def _do_copy(sess, src_fh, src_stateid, dst_fh, dst_stateid,
+             src_offset=0, dst_offset=0, count=0,
+             consecutive=0, synchronous=1):
+    ops = [op.putfh(src_fh), op.savefh(), op.putfh(dst_fh),
+           op.copy(src_stateid, dst_stateid, src_offset, dst_offset,
+                   count, consecutive, synchronous, [])]
+    return sess.compound(ops)
+
+def _poll_offload_status(sess, dst_fh, copy_stateid, timeout=120):
+    deadline = time.time() + timeout
+    while time.time() < deadline:
+        ops = [op.putfh(dst_fh), op.offload_status(copy_stateid)]
+        res = sess.compound(ops)
+        check(res)
+        status_res = res.resarray[-1]
+        if status_res.osr_complete:
+            return status_res
+        time.sleep(1)
+    fail("OFFLOAD_STATUS did not complete within %d seconds" % timeout)
+
+def _create_and_open(sess, name):
+    res = create_file(sess, name)
+    check(res)
+    fh = res.resarray[-1].object
+    stateid = res.resarray[-2].stateid
+    return fh, stateid
+
+def _write_data(sess, fh, stateid, data, offset=0):
+    """Write data in chunks bounded by the session's max request size."""
+    chunk = sess.fore_channel.maxrequestsize - 1024
+    pos = 0
+    while pos < len(data):
+        res = write_file(sess, fh, data[pos:pos + chunk], offset + pos, stateid)
+        check(res, msg="WRITE at offset %d" % (offset + pos))
+        pos += res.count
+
+def _verify_data(sess, fh, stateid, data, offset=0):
+    """Read back and compare data in chunks bounded by max response size."""
+    chunk = sess.fore_channel.maxresponsesize - 1024
+    pos = 0
+    while pos < len(data):
+        res = read_file(sess, fh, offset + pos, min(chunk, len(data) - pos),
+                        stateid)
+        check(res)
+        if not res.data:
+            fail("Short read at offset %d" % (offset + pos))
+        if res.data != data[pos:pos + len(res.data)]:
+            fail("Data mismatch at offset %d" % (offset + pos))
+        pos += len(res.data)
+
+def testSyncCopy(t, env):
+    """synchronous copy of a file and verify contents
+
+    FLAGS: copy
+    CODE: COPY1
+    """
+    sess = env.c1.new_client_session(env.testname(t))
+    src_fh, src_stateid = _create_and_open(sess, env.testname(t))
+    data = b"A" * 65536
+    _write_data(sess, src_fh, src_stateid, data)
+
+    dst_fh, dst_stateid = _create_and_open(sess, env.testname(t) + b"_dst")
+
+    res = _do_copy(sess, src_fh, src_stateid, dst_fh, dst_stateid,
+                   count=len(data), synchronous=1)
+    check(res)
+    cr = res.resarray[-1]
+
+    # A synchronous COPY was requested, but RFC 7862 permits the server to
+    # perform the copy asynchronously anyway; cr_requirements.cr_synchronous
+    # reports what actually happened.  Honor either, but verify the byte count.
+    if cr.cr_resok4.cr_requirements.cr_synchronous:
+        if cr.cr_response.wr_count != len(data):
+            fail("Synchronous copy expected %d bytes, got %d" %
+                 (len(data), cr.cr_response.wr_count))
+    else:
+        copy_stateid = cr.cr_response.wr_callback_id[0]
+        status = _poll_offload_status(sess, dst_fh, copy_stateid)
+        if status.osr_complete[0] != NFS4_OK:
+            fail("Async copy completed with error: %d" % status.osr_complete[0])
+        if status.osr_count != len(data):
+            fail("Expected %d bytes copied, got %d" %
+                 (len(data), status.osr_count))
+
+    _verify_data(sess, dst_fh, dst_stateid, data)
+
 def testZeroLengthCopy(t, env):
     """test that zero-length copy copies to EOF
 

-- 
2.55.0