NFS: Support NFS4ERR_LEASE_MOVED recovery in state manager
A migration on the FSID in play for the current NFS operation
is reported via the error status code NFS4ERR_MOVED.
"Lease moved" means that a migration has occurred on some other
FSID than the one for the current operation. It's a signal that
the client should take action immediately to handle a migration
that it may not have noticed otherwise. This is so that the
client's lease does not expire unnoticed on the destination server.
In NFSv4.0, a moved lease is reported with the NFS4ERR_LEASE_MOVED
error status code.
To recover from NFS4ERR_LEASE_MOVED, check each FSID for that server
to see if it is still present. Invoke nfs4_try_migration() if the
FSID is no longer present on the server.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index ba0db18..552706d 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -1233,6 +1233,22 @@
}
EXPORT_SYMBOL_GPL(nfs4_schedule_migration_recovery);
+/**
+ * nfs4_schedule_lease_moved_recovery - start lease-moved recovery
+ *
+ * @clp: server to check for moved leases
+ *
+ */
+void nfs4_schedule_lease_moved_recovery(struct nfs_client *clp)
+{
+ dprintk("%s: scheduling lease-moved recovery for client ID %llx on %s\n",
+ __func__, clp->cl_clientid, clp->cl_hostname);
+
+ set_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state);
+ nfs4_schedule_state_manager(clp);
+}
+EXPORT_SYMBOL_GPL(nfs4_schedule_lease_moved_recovery);
+
int nfs4_wait_clnt_recover(struct nfs_client *clp)
{
int res;
@@ -1661,7 +1677,6 @@
nfs4_state_end_reclaim_reboot(clp);
break;
case -NFS4ERR_STALE_CLIENTID:
- case -NFS4ERR_LEASE_MOVED:
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
nfs4_state_clear_reclaim_reboot(clp);
nfs4_state_start_reclaim_reboot(clp);
@@ -1975,6 +1990,55 @@
return 0;
}
+/*
+ * Test each nfs_server on the clp's cl_superblocks list to see
+ * if it's moved to another server. Stop when the server no longer
+ * returns NFS4ERR_LEASE_MOVED.
+ */
+static int nfs4_handle_lease_moved(struct nfs_client *clp)
+{
+ const struct nfs4_state_maintenance_ops *ops =
+ clp->cl_mvops->state_renewal_ops;
+ struct nfs_server *server;
+ struct rpc_cred *cred;
+
+ dprintk("%s: lease moved reported on \"%s\"\n", __func__,
+ clp->cl_hostname);
+
+ spin_lock(&clp->cl_lock);
+ cred = ops->get_state_renewal_cred_locked(clp);
+ spin_unlock(&clp->cl_lock);
+ if (cred == NULL)
+ return -NFS4ERR_NOENT;
+
+ clp->cl_mig_gen++;
+restart:
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ struct inode *inode;
+ int status;
+
+ if (server->mig_gen == clp->cl_mig_gen)
+ continue;
+ server->mig_gen = clp->cl_mig_gen;
+
+ rcu_read_unlock();
+
+ inode = server->super->s_root->d_inode;
+ status = nfs4_proc_fsid_present(inode, cred);
+ if (status != -NFS4ERR_MOVED)
+ goto restart; /* wasn't this one */
+ if (nfs4_try_migration(server, cred) == -NFS4ERR_LEASE_MOVED)
+ goto restart; /* there are more */
+ goto out;
+ }
+ rcu_read_unlock();
+
+out:
+ put_rpccred(cred);
+ return 0;
+}
+
/**
* nfs4_discover_server_trunking - Detect server IP address trunking
*
@@ -2312,6 +2376,13 @@
goto out_error;
}
+ if (test_and_clear_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state)) {
+ section = "lease moved";
+ status = nfs4_handle_lease_moved(clp);
+ if (status < 0)
+ goto out_error;
+ }
+
/* First recover reboot state... */
if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
section = "reclaim reboot";