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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 08/11] NFSD: Update find_client_in_id_table() to handle courtesy client
Date:   Thu, 17 Mar 2022 00:43:45 -0700
Message-Id: <1647503028-11966-9-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_client_in_id_table to:
 . skip client with CLIENT_EXPIRED; discarded courtesy client
 . if courtesy client was found then set CLIENT_RECONNECTED
   state so caller can take appropriate action.

Update find_confirmed_client to discard courtesy client.
Update lookup_clientid to call find_client_in_id_table directly.
Update set_client to create client record for courtesy client.
Update find_cpntf_state to discard courtesy client.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
---
 fs/nfsd/nfs4state.c | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 3b1e857eabee..102b4aae286d 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -2893,6 +2893,8 @@ find_client_in_id_table(struct list_head *tbl, clientid_t *clid, bool sessions)
 		if (same_clid(&clp->cl_clientid, clid)) {
 			if ((bool)clp->cl_minorversion != sessions)
 				return NULL;
+			if (nfsd4_courtesy_clnt_expired(clp))
+				continue;
 			renew_client_locked(clp);
 			return clp;
 		}
@@ -2904,9 +2906,15 @@ static struct nfs4_client *
 find_confirmed_client(clientid_t *clid, bool sessions, struct nfsd_net *nn)
 {
 	struct list_head *tbl = nn->conf_id_hashtbl;
+	struct nfs4_client *clp;
 
 	lockdep_assert_held(&nn->client_lock);
-	return find_client_in_id_table(tbl, clid, sessions);
+	clp = find_client_in_id_table(tbl, clid, sessions);
+	if (clp && clp->cl_cs_client_state == NFSD4_CLIENT_RECONNECTED) {
+		nfsd4_discard_courtesy_clnt(clp);
+		clp = NULL;
+	}
+	return clp;
 }
 
 static struct nfs4_client *
@@ -4822,9 +4830,10 @@ static struct nfs4_client *lookup_clientid(clientid_t *clid, bool sessions,
 						struct nfsd_net *nn)
 {
 	struct nfs4_client *found;
+	struct list_head *tbl = nn->conf_id_hashtbl;
 
 	spin_lock(&nn->client_lock);
-	found = find_confirmed_client(clid, sessions, nn);
+	found = find_client_in_id_table(tbl, clid, sessions);
 	if (found)
 		atomic_inc(&found->cl_rpc_users);
 	spin_unlock(&nn->client_lock);
@@ -4849,6 +4858,8 @@ static __be32 set_client(clientid_t *clid,
 	cstate->clp = lookup_clientid(clid, false, nn);
 	if (!cstate->clp)
 		return nfserr_expired;
+	if (cstate->clp->cl_cs_client_state == NFSD4_CLIENT_RECONNECTED)
+		nfsd4_client_record_create(cstate->clp);
 	return nfs_ok;
 }
 
@@ -6168,6 +6179,13 @@ static __be32 find_cpntf_state(struct nfsd_net *nn, stateid_t *st,
 	found = lookup_clientid(&cps->cp_p_clid, true, nn);
 	if (!found)
 		goto out;
+	if (found->cl_cs_client_state == NFSD4_CLIENT_RECONNECTED) {
+		nfsd4_discard_courtesy_clnt(found);
+		if (atomic_dec_and_lock(&found->cl_rpc_users,
+				&nn->client_lock))
+			spin_unlock(&nn->client_lock);
+		goto out;
+	}
 
 	*stid = find_stateid_by_type(found, &cps->cp_p_stateid,
 			NFS4_DELEG_STID|NFS4_OPEN_STID|NFS4_LOCK_STID);
-- 
2.9.5