NFSv4: Iterate through all nfs_clients when the server recalls a delegation

The same delegation may have been handed out to more than one nfs_client.
Ensure that if a recall occurs, we return all instances.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 35 insertions, 0 deletions

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 7a15832369e9..685c43f810c1 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -276,6 +276,41 @@ struct nfs_client *nfs_find_client(const struct sockaddr *addr, u32 nfsversion)
 }
 
 /*
+ * Find a client by IP address and protocol version
+ * - returns NULL if no such client
+ */
+struct nfs_client *nfs_find_client_next(struct nfs_client *clp)
+{
+        struct sockaddr *sap = (struct sockaddr *)&clp->cl_addr;
+        u32 nfsvers = clp->rpc_ops->version;
+
+        spin_lock(&nfs_client_lock);
+        list_for_each_entry_continue(clp, &nfs_client_list, cl_share_link) {
+                struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
+
+                /* Don't match clients that failed to initialise properly */
+                if (clp->cl_cons_state != NFS_CS_READY)
+                        continue;
+
+                /* Different NFS versions cannot share the same nfs_client */
+                if (clp->rpc_ops->version != nfsvers)
+                        continue;
+
+                if (sap->sa_family != clap->sa_family)
+                        continue;
+                /* Match only the IP address, not the port number */
+                if (!nfs_sockaddr_match_ipaddr(sap, clap))
+                        continue;
+
+                atomic_inc(&clp->cl_count);
+                spin_unlock(&nfs_client_lock);
+                return clp;
+        }
+        spin_unlock(&nfs_client_lock);
+        return NULL;
+}
+
+/*
  * Find an nfs_client on the list that matches the initialisation data
  * that is supplied.
  */