nfsd4: fix mixed 4.0/4.1 handling, 4.1 reboot

Instead of failing to find client entries which don't match the
minorversion, we should be finding them, then either erroring out or
expiring them as appropriate.

This also fixes a problem which would cause the 4.1 server to fail to
recognize clients after a second reboot.

Reported-by: Casey Bodley <cbodley@citi.umich.edu>
Reviewed-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 17 insertions, 20 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 0c61cc1eadca..73adcfb2dc17 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1134,39 +1134,30 @@ find_unconfirmed_client(clientid_t *clid)
         return NULL;
 }
 
-/*
- * FIXME: we need to unify the clientid namespaces for nfsv4.x
- * and correctly deal with client upgrade/downgrade in EXCHANGE_ID
- * and SET_CLIENTID{,_CONFIRM}
- */
 static bool clp_used_exchangeid(struct nfs4_client *clp)
 {
         return clp->cl_exchange_flags != 0;
-}
+} 
 
 static struct nfs4_client *
-find_confirmed_client_by_str(const char *dname, unsigned int hashval,
-                             bool use_exchange_id)
+find_confirmed_client_by_str(const char *dname, unsigned int hashval)
 {
         struct nfs4_client *clp;
 
         list_for_each_entry(clp, &conf_str_hashtbl[hashval], cl_strhash) {
-                if (same_name(clp->cl_recdir, dname) &&
-                    clp_used_exchangeid(clp) == use_exchange_id)
+                if (same_name(clp->cl_recdir, dname))
                         return clp;
         }
         return NULL;
 }
 
 static struct nfs4_client *
-find_unconfirmed_client_by_str(const char *dname, unsigned int hashval,
-                               bool use_exchange_id)
+find_unconfirmed_client_by_str(const char *dname, unsigned int hashval)
 {
         struct nfs4_client *clp;
 
         list_for_each_entry(clp, &unconf_str_hashtbl[hashval], cl_strhash) {
-                if (same_name(clp->cl_recdir, dname) &&
-                    clp_used_exchangeid(clp) == use_exchange_id)
+                if (same_name(clp->cl_recdir, dname))
                         return clp;
         }
         return NULL;
@@ -1357,8 +1348,12 @@ nfsd4_exchange_id(struct svc_rqst *rqstp,
         nfs4_lock_state();
         status = nfs_ok;
 
-        conf = find_confirmed_client_by_str(dname, strhashval, true);
+        conf = find_confirmed_client_by_str(dname, strhashval);
         if (conf) {
+                if (!clp_used_exchangeid(conf)) {
+                        status = nfserr_clid_inuse; /* XXX: ? */
+                        goto out;
+                }
                 if (!same_verf(&verf, &conf->cl_verifier)) {
                         /* 18.35.4 case 8 */
                         if (exid->flags & EXCHGID4_FLAG_UPD_CONFIRMED_REC_A) {
@@ -1399,7 +1394,7 @@ nfsd4_exchange_id(struct svc_rqst *rqstp,
                 goto out;
         }
 
-        unconf  = find_unconfirmed_client_by_str(dname, strhashval, true);
+        unconf  = find_unconfirmed_client_by_str(dname, strhashval);
         if (unconf) {
                 /*
                  * Possible retry or client restart.  Per 18.35.4 case 4,
@@ -1799,10 +1794,12 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
         strhashval = clientstr_hashval(dname);
 
         nfs4_lock_state();
-        conf = find_confirmed_client_by_str(dname, strhashval, false);
+        conf = find_confirmed_client_by_str(dname, strhashval);
         if (conf) {
                 /* RFC 3530 14.2.33 CASE 0: */
                 status = nfserr_clid_inuse;
+                if (clp_used_exchangeid(conf))
+                        goto out;
                 if (!same_creds(&conf->cl_cred, &rqstp->rq_cred)) {
                         char addr_str[INET6_ADDRSTRLEN];
                         rpc_ntop((struct sockaddr *) &conf->cl_addr, addr_str,
@@ -1817,7 +1814,7 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
          * has a description of SETCLIENTID request processing consisting
          * of 5 bullet points, labeled as CASE0 - CASE4 below.
          */
-        unconf = find_unconfirmed_client_by_str(dname, strhashval, false);
+        unconf = find_unconfirmed_client_by_str(dname, strhashval);
         status = nfserr_resource;
         if (!conf) {
                 /*
@@ -1962,7 +1959,7 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp,
                         unsigned int hash =
                                 clientstr_hashval(unconf->cl_recdir);
                         conf = find_confirmed_client_by_str(unconf->cl_recdir,
-                                                            hash, false);
+                                                            hash);
                         if (conf) {
                                 nfsd4_remove_clid_dir(conf);
                                 expire_client(conf);
@@ -4106,7 +4103,7 @@ nfs4_has_reclaimed_state(const char *name, bool use_exchange_id)
         unsigned int strhashval = clientstr_hashval(name);
         struct nfs4_client *clp;
 
-        clp = find_confirmed_client_by_str(name, strhashval, use_exchange_id);
+        clp = find_confirmed_client_by_str(name, strhashval);
         return clp ? 1 : 0;
 }