Received-SPF: pass (google.com: domain of linux-nfs-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Dai Ngo <dai.ngo@oracle.com>
To:     chuck.lever@oracle.com, bfields@fieldses.org
Cc:     jlayton@redhat.com, viro@zeniv.linux.org.uk,
        linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: [PATCH RFC v17 07/11] NFSD: Update find_in_sessionid_hashtbl() to handle courtesy client
Date:   Thu, 17 Mar 2022 00:43:44 -0700
Message-Id: <1647503028-11966-8-git-send-email-dai.ngo@oracle.com>
In-Reply-To: <1647503028-11966-1-git-send-email-dai.ngo@oracle.com>
References: <1647503028-11966-1-git-send-email-dai.ngo@oracle.com>
Precedence: bulk

Update find_in_sessionid_hashtbl to:
 . skip client with CLIENT_EXPIRED state; discarded courtesy client.
 . if courtesy client was found then set CLIENT_RECONNECTED so caller
   can take appropriate action.

Update nfsd4_sequence and nfsd4_bind_conn_to_session to create client
record for courtesy client with CLIENT_RECONNECTED state.

Update nfsd4_destroy_session to discard courtesy client with
CLIENT_RECONNECTED state.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
---
 fs/nfsd/nfs4state.c | 34 ++++++++++++++++++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index dc0e60bf694c..3b1e857eabee 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1935,13 +1935,22 @@ find_in_sessionid_hashtbl(struct nfs4_sessionid *sessionid, struct net *net,
 {
 	struct nfsd4_session *session;
 	__be32 status = nfserr_badsession;
+	struct nfs4_client *clp;
 
 	session = __find_in_sessionid_hashtbl(sessionid, net);
 	if (!session)
 		goto out;
+	clp = session->se_client;
+	if (nfsd4_courtesy_clnt_expired(clp)) {
+		session = NULL;
+		goto out;
+	}
 	status = nfsd4_get_session_locked(session);
-	if (status)
+	if (status) {
 		session = NULL;
+		if (clp->cl_cs_client_state == NFSD4_CLIENT_RECONNECTED)
+			nfsd4_discard_courtesy_clnt(clp);
+	}
 out:
 	*ret = status;
 	return session;
@@ -3643,6 +3652,7 @@ __be32 nfsd4_bind_conn_to_session(struct svc_rqst *rqstp,
 	struct nfsd4_session *session;
 	struct net *net = SVC_NET(rqstp);
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+	struct nfs4_client *clp;
 
 	if (!nfsd4_last_compound_op(rqstp))
 		return nfserr_not_only_op;
@@ -3675,6 +3685,13 @@ __be32 nfsd4_bind_conn_to_session(struct svc_rqst *rqstp,
 	nfsd4_init_conn(rqstp, conn, session);
 	status = nfs_ok;
 out:
+	clp = session->se_client;
+	if (clp->cl_cs_client_state == NFSD4_CLIENT_RECONNECTED) {
+		if (status == nfs_ok)
+			nfsd4_client_record_create(clp);
+		else
+			nfsd4_discard_courtesy_clnt(clp);
+	}
 	nfsd4_put_session(session);
 out_no_session:
 	return status;
@@ -3697,6 +3714,7 @@ nfsd4_destroy_session(struct svc_rqst *r, struct nfsd4_compound_state *cstate,
 	int ref_held_by_me = 0;
 	struct net *net = SVC_NET(r);
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+	struct nfs4_client *clp;
 
 	status = nfserr_not_only_op;
 	if (nfsd4_compound_in_session(cstate, sessionid)) {
@@ -3709,6 +3727,12 @@ nfsd4_destroy_session(struct svc_rqst *r, struct nfsd4_compound_state *cstate,
 	ses = find_in_sessionid_hashtbl(sessionid, net, &status);
 	if (!ses)
 		goto out_client_lock;
+	clp = ses->se_client;
+	if (clp->cl_cs_client_state == NFSD4_CLIENT_RECONNECTED) {
+		status = nfserr_badsession;
+		nfsd4_discard_courtesy_clnt(clp);
+		goto out_put_session;
+	}
 	status = nfserr_wrong_cred;
 	if (!nfsd4_mach_creds_match(ses->se_client, r))
 		goto out_put_session;
@@ -3813,7 +3837,7 @@ nfsd4_sequence(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
 	struct xdr_stream *xdr = resp->xdr;
 	struct nfsd4_session *session;
-	struct nfs4_client *clp;
+	struct nfs4_client *clp = NULL;
 	struct nfsd4_slot *slot;
 	struct nfsd4_conn *conn;
 	__be32 status;
@@ -3923,6 +3947,12 @@ nfsd4_sequence(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	if (conn)
 		free_conn(conn);
 	spin_unlock(&nn->client_lock);
+	if (clp && clp->cl_cs_client_state == NFSD4_CLIENT_RECONNECTED) {
+		if (status == nfs_ok)
+			nfsd4_client_record_create(clp);
+		else
+			nfsd4_discard_courtesy_clnt(clp);
+	}
 	return status;
 out_put_session:
 	nfsd4_put_session_locked(session);
-- 
2.9.5