[07/14] nfsd4: keep finer-grained callback status

Commit Message

Bruce Fields Jan. 11, 2011, 4:21 p.m. UTC

None

Patch

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 18b740b..d32f49d 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -470,8 +470,6 @@  static int max_cb_time(void)
 	return max(nfsd4_lease/10, (time_t)1) * HZ;
 }
 
-/* Reference counting, callback cleanup, etc., all look racy as heck.
- * And why is cl_cb_set an atomic? */
 
 static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *conn, struct nfsd4_session *ses)
 {
@@ -526,14 +524,20 @@  static void warn_no_callback_path(struct nfs4_client *clp, int reason)
 		(int)clp->cl_name.len, clp->cl_name.data, reason);
 }
 
+static void nfsd4_mark_cb_down(struct nfs4_client *clp, int reason)
+{
+	clp->cl_cb_state = NFSD4_CB_DOWN;
+	warn_no_callback_path(clp, reason);
+}
+
 static void nfsd4_cb_probe_done(struct rpc_task *task, void *calldata)
 {
 	struct nfs4_client *clp = container_of(calldata, struct nfs4_client, cl_cb_null);
 
 	if (task->tk_status)
-		warn_no_callback_path(clp, task->tk_status);
+		nfsd4_mark_cb_down(clp, task->tk_status);
 	else
-		atomic_set(&clp->cl_cb_set, 1);
+		clp->cl_cb_state = NFSD4_CB_UP;
 }
 
 static const struct rpc_call_ops nfsd4_cb_probe_ops = {
@@ -579,14 +583,15 @@  static void do_probe_callback(struct nfs4_client *clp)
  */
 void nfsd4_probe_callback(struct nfs4_client *clp)
 {
+	/* XXX: atomicity?  Also, should we be using cl_cb_flags? */
+	clp->cl_cb_state = NFSD4_CB_UNKNOWN;
 	set_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_cb_flags);
 	do_probe_callback(clp);
 }
 
 void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *conn)
 {
-	BUG_ON(atomic_read(&clp->cl_cb_set));
-
+	clp->cl_cb_state = NFSD4_CB_UNKNOWN;
 	spin_lock(&clp->cl_lock);
 	memcpy(&clp->cl_cb_conn, conn, sizeof(struct nfs4_cb_conn));
 	spin_unlock(&clp->cl_lock);
@@ -693,8 +698,7 @@  static void nfsd4_cb_recall_done(struct rpc_task *task, void *calldata)
 		break;
 	default:
 		/* Network partition? */
-		atomic_set(&clp->cl_cb_set, 0);
-		warn_no_callback_path(clp, task->tk_status);
+		nfsd4_mark_cb_down(clp, task->tk_status);
 		if (current_rpc_client != task->tk_client) {
 			/* queue a callback on the new connection: */
 			atomic_inc(&dp->dl_count);
@@ -707,10 +711,8 @@  static void nfsd4_cb_recall_done(struct rpc_task *task, void *calldata)
 		task->tk_status = 0;
 		rpc_restart_call_prepare(task);
 		return;
-	} else {
-		atomic_set(&clp->cl_cb_set, 0);
-		warn_no_callback_path(clp, task->tk_status);
-	}
+	} else
+		nfsd4_mark_cb_down(clp, task->tk_status);
 }
 
 static void nfsd4_cb_recall_release(void *calldata)
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 290370b..919ad25 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1071,7 +1071,7 @@  static struct nfs4_client *create_client(struct xdr_netobj name, char *recdir,
 
 	memcpy(clp->cl_recdir, recdir, HEXDIR_LEN);
 	atomic_set(&clp->cl_refcount, 0);
-	atomic_set(&clp->cl_cb_set, 0);
+	clp->cl_cb_state = NFSD4_CB_UNKNOWN;
 	INIT_LIST_HEAD(&clp->cl_idhash);
 	INIT_LIST_HEAD(&clp->cl_strhash);
 	INIT_LIST_HEAD(&clp->cl_openowners);
@@ -2003,7 +2003,6 @@  nfsd4_setclientid_confirm(struct svc_rqst *rqstp,
 		if (!same_creds(&conf->cl_cred, &unconf->cl_cred))
 			status = nfserr_clid_inuse;
 		else {
-			atomic_set(&conf->cl_cb_set, 0);
 			nfsd4_change_callback(conf, &unconf->cl_cb_conn);
 			nfsd4_probe_callback(conf);
 			expire_client(unconf);
@@ -2633,7 +2632,8 @@  nfs4_open_delegation(struct svc_fh *fh, struct nfsd4_open *open, struct nfs4_sta
 {
 	struct nfs4_delegation *dp;
 	struct nfs4_stateowner *sop = stp->st_stateowner;
-	int cb_up = atomic_read(&sop->so_client->cl_cb_set);
+	/* XXX: or unknown and nfsv4.1: */
+	int cb_up = (sop->so_client->cl_cb_state == NFSD4_CB_UP);
 	struct file_lock *fl;
 	int status, flag = 0;
 
@@ -2823,7 +2823,7 @@  nfsd4_renew(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	renew_client(clp);
 	status = nfserr_cb_path_down;
 	if (!list_empty(&clp->cl_delegations)
-			&& !atomic_read(&clp->cl_cb_set))
+			&& clp->cl_cb_state != NFSD4_CB_UP)
 		goto out;
 	status = nfs_ok;
 out:
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 442f6d8..32ff615 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -242,7 +242,10 @@  struct nfs4_client {
 	unsigned long		cl_cb_flags;
 	struct rpc_clnt		*cl_cb_client;
 	u32			cl_cb_ident;
-	atomic_t		cl_cb_set;
+#define NFSD4_CB_UP		0
+#define NFSD4_CB_UNKNOWN	1
+#define NFSD4_CB_DOWN		2
+	int			cl_cb_state;
 	struct nfsd4_callback	cl_cb_null;
 	struct nfsd4_session	*cl_cb_session;