[PATCH v1 2/8] pynfs: add test for OPEN(CLAIM_FH) delegation request on an open file

[Chuck Lever <cel@kernel.org>]

A client that wants a delegation on a file it already has open can
repeat the OPEN with CLAIM_FH, the same open-owner, and a want bit.
The server treats that OPEN as an upgrade of the existing open, and
no test checks that a delegation can come back from one.

Add DELEG28. It keeps the file open with WANT_NO_DELEG, then sends
OPEN(CLAIM_FH) with WANT_READ_DELEG from the same open-owner. The
reply has to carry a read delegation and the original open stateid
with its seqid incremented by one.

Signed-off-by: Chuck Lever <cel@kernel.org>
---
 nfs4.1/server41tests/st_delegation.py | 41 +++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/nfs4.1/server41tests/st_delegation.py b/nfs4.1/server41tests/st_delegation.py
index c35ce8f5ec3b..56d227127a15 100644
--- a/nfs4.1/server41tests/st_delegation.py
+++ b/nfs4.1/server41tests/st_delegation.py
@@ -686,3 +686,44 @@ def testClaimFHReadDeleg(t, env):
     check(res)
     res = close_file(sess1, fh, stateid=stateid)
     check(res)
+
+def testClaimFHUpgradeReadDeleg(t, env):
+    """OPEN(CLAIM_FH) with WANT_READ_DELEG from an open-owner that
+       already has the file open
+
+    FLAGS: open deleg all
+    CODE: DELEG29
+    """
+    name = env.testname(t)
+    sess1 = env.c1.new_client_session(b"%s_1" % name)
+    res = create_file(sess1, name, access=OPEN4_SHARE_ACCESS_READ |
+                      OPEN4_SHARE_ACCESS_WANT_NO_DELEG)
+    check(res)
+    fh = res.resarray[-1].object
+    stateid = res.resarray[-2].stateid
+
+    # The second pass is the retry that _open_claim_fh_retry() makes.
+    # Each OPEN bumps the seqid, so count them here.
+    seqid = stateid.seqid
+    for attempt in range(2):
+        res = _open_claim_fh(sess1, fh, name, OPEN4_SHARE_ACCESS_READ |
+                             OPEN4_SHARE_ACCESS_WANT_READ_DELEG)
+        check(res)
+        seqid += 1
+        upgraded = res.resarray[-1].stateid
+        if upgraded.other != stateid.other:
+            fail("OPEN by the same open-owner returned a different stateid")
+        if upgraded.seqid != seqid:
+            fail("Expected open stateid seqid %i, got %i" %
+                 (seqid, upgraded.seqid))
+        deleg = res.resarray[-1].delegation
+        if _got_deleg(deleg):
+            break
+    if deleg.delegation_type != OPEN_DELEGATE_READ:
+        _delegreturn(sess1, fh, deleg)
+        fail("Expected a read delegation, got %s" % _deleg_desc(deleg))
+
+    res = sess1.compound([op.putfh(fh), op.delegreturn(deleg.read.stateid)])
+    check(res)
+    res = close_file(sess1, fh, stateid=upgraded)
+    check(res)
-- 
2.55.0