nfs4: Fix handling of retried CLOSE requests

src/add-ons/kernel/file_systems/nfs4/NFS4Object.cpp

@@ -24,7 +24,6 @@ NFS4Object::HandleErrors(uint32 nfs4Error, RPC::Server* serv,
 	ASSERT(nfs4Error != NFS4ERR_CLID_INUSE);
 	ASSERT(nfs4Error != NFS4ERR_NOFILEHANDLE);
 	ASSERT(nfs4Error != NFS4ERR_BAD_STATEID);
-	ASSERT(nfs4Error != NFS4ERR_BAD_SEQID);
 	ASSERT(nfs4Error != NFS4ERR_RESTOREFH);
 	ASSERT(nfs4Error != NFS4ERR_LOCKS_HELD);
 	ASSERT(nfs4Error != NFS4ERR_OP_ILLEGAL);
@@ -36,6 +35,12 @@ NFS4Object::HandleErrors(uint32 nfs4Error, RPC::Server* serv,
 		case NFS4_OK:
 			return false;
 
+		// retransmission of CLOSE caused seqid to fall back
+		case NFS4ERR_BAD_SEQID:
+			ASSERT(sequence != NULL);
+			(*sequence)++;
+			return true;
+
 		// server needs more time, we need to wait
 		case NFS4ERR_LOCKED:
 		case NFS4ERR_DELAY:

src/add-ons/kernel/file_systems/nfs4/OpenState.cpp

@@ -290,6 +290,14 @@ OpenState::Close()
 
 		sequence += IncrementSequence(reply.NFS4Error());
 
+		// RFC 3530 8.10.1. Some servers does not do anything to help client
+		// recognize retried CLOSE requests so we just assume that BAD_STATEID
+		// on CLOSE request is just a result of retransmission.
+		if (reply.NFS4Error() == NFS4ERR_BAD_STATEID) {
+	 		fFileSystem->OpenOwnerSequenceUnlock(sequence);
+			return B_OK;
+		}
+
 		if (HandleErrors(reply.NFS4Error(), serv, NULL, this, &sequence))
 			continue;
  		fFileSystem->OpenOwnerSequenceUnlock(sequence);