sunrpc: close connection when a request is irretrievably lost.

If we drop a request in the sunrpc layer, either due kmalloc failure,
or due to a cache miss when we could not queue the request for later
replay, then close the connection to encourage the client to retry sooner.

Note that if the drop happens in the NFS layer, NFSERR_JUKEBOX
(aka NFS4ERR_DELAY) is returned to guide the client concerning
replay.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 8 insertions, 3 deletions

diff --git a/net/sunrpc/svcauth_unix.c b/net/sunrpc/svcauth_unix.c
index 20731161098..e91b550bc83 100644
--- a/net/sunrpc/svcauth_unix.c
+++ b/net/sunrpc/svcauth_unix.c
@@ -674,6 +674,8 @@ static struct group_info *unix_gid_find(uid_t uid, struct svc_rqst *rqstp)
         switch (ret) {
         case -ENOENT:
                 return ERR_PTR(-ENOENT);
+        case -ETIMEDOUT:
+                return ERR_PTR(-ESHUTDOWN);
         case 0:
                 gi = get_group_info(ug->gi);
                 cache_put(&ug->h, &unix_gid_cache);
@@ -720,8 +722,9 @@ svcauth_unix_set_client(struct svc_rqst *rqstp)
         switch (cache_check(&ip_map_cache, &ipm->h, &rqstp->rq_chandle)) {
                 default:
                         BUG();
-                case -EAGAIN:
                 case -ETIMEDOUT:
+                        return SVC_CLOSE;
+                case -EAGAIN:
                         return SVC_DROP;
                 case -ENOENT:
                         return SVC_DENIED;
@@ -736,6 +739,8 @@ svcauth_unix_set_client(struct svc_rqst *rqstp)
         switch (PTR_ERR(gi)) {
         case -EAGAIN:
                 return SVC_DROP;
+        case -ESHUTDOWN:
+                return SVC_CLOSE;
         case -ENOENT:
                 break;
         default:
@@ -776,7 +781,7 @@ svcauth_null_accept(struct svc_rqst *rqstp, __be32 *authp)
         cred->cr_gid = (gid_t) -1;
         cred->cr_group_info = groups_alloc(0);
         if (cred->cr_group_info == NULL)
-                return SVC_DROP; /* kmalloc failure - client must retry */
+                return SVC_CLOSE; /* kmalloc failure - client must retry */
 
         /* Put NULL verifier */
         svc_putnl(resv, RPC_AUTH_NULL);
@@ -840,7 +845,7 @@ svcauth_unix_accept(struct svc_rqst *rqstp, __be32 *authp)
                 goto badcred;
         cred->cr_group_info = groups_alloc(slen);
         if (cred->cr_group_info == NULL)
-                return SVC_DROP;
+                return SVC_CLOSE;
         for (i = 0; i < slen; i++)
                 GROUP_AT(cred->cr_group_info, i) = svc_getnl(argv);
         if (svc_getu32(argv) != htonl(RPC_AUTH_NULL) || svc_getu32(argv) != 0) {