NFSD: Reading a fault injection file prints a state count

I also log basic information that I can figure out about the type of
state (such as number of locks for each client IP address).  This can be
useful for checking that state was actually dropped and later for
checking if the client was able to recover.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

fs/nfsd/fault_inject.c

@@ -14,28 +14,34 @@
 struct nfsd_fault_inject_op {
 	char *file;
 	u64 (*forget)(struct nfs4_client *, u64);
+	u64 (*print)(struct nfs4_client *, u64);
 };
 
 static struct nfsd_fault_inject_op inject_ops[] = {
 	{
 		.file   = "forget_clients",
 		.forget = nfsd_forget_client,
+		.print  = nfsd_print_client,
 	},
 	{
 		.file   = "forget_locks",
 		.forget = nfsd_forget_client_locks,
+		.print  = nfsd_print_client_locks,
 	},
 	{
 		.file   = "forget_openowners",
 		.forget = nfsd_forget_client_openowners,
+		.print  = nfsd_print_client_openowners,
 	},
 	{
 		.file   = "forget_delegations",
 		.forget = nfsd_forget_client_delegations,
+		.print  = nfsd_print_client_delegations,
 	},
 	{
 		.file   = "recall_delegations",
 		.forget = nfsd_recall_client_delegations,
+		.print  = nfsd_print_client_delegations,
 	},
 };
 
@@ -59,9 +65,12 @@ static int nfsd_inject_set(void *op_ptr, u64 val)
 	return 0;
 }
 
-static int nfsd_inject_get(void *data, u64 *val)
+static int nfsd_inject_get(void *op_ptr, u64 *val)
 {
-	*val = 0;
+	struct nfsd_fault_inject_op *op = op_ptr;
+	nfs4_lock_state();
+	*val = nfsd_for_n_state(0, op->print);
+	nfs4_unlock_state();
 	return 0;
 }
 

fs/nfsd/nfs4state.c

@@ -4611,6 +4611,22 @@ u64 nfsd_forget_client(struct nfs4_client *clp, u64 max)
 	return 1;
 }
 
+u64 nfsd_print_client(struct nfs4_client *clp, u64 num)
+{
+	char buf[INET6_ADDRSTRLEN];
+	rpc_ntop((struct sockaddr *)&clp->cl_addr, buf, 129);
+	printk(KERN_INFO "NFS Client: %s\n", buf);
+	return 1;
+}
+
+static void nfsd_print_count(struct nfs4_client *clp, unsigned int count,
+			     const char *type)
+{
+	char buf[INET6_ADDRSTRLEN];
+	rpc_ntop((struct sockaddr *)&clp->cl_addr, buf, 129);
+	printk(KERN_INFO "NFS Client: %s has %u %s\n", buf, count, type);
+}
+
 static u64 nfsd_foreach_client_lock(struct nfs4_client *clp, u64 max, void (*func)(struct nfs4_lockowner *))
 {
 	struct nfs4_openowner *oop;
@@ -4637,6 +4653,13 @@ u64 nfsd_forget_client_locks(struct nfs4_client *clp, u64 max)
 	return nfsd_foreach_client_lock(clp, max, release_lockowner);
 }
 
+u64 nfsd_print_client_locks(struct nfs4_client *clp, u64 max)
+{
+	u64 count = nfsd_foreach_client_lock(clp, max, NULL);
+	nfsd_print_count(clp, count, "locked files");
+	return count;
+}
+
 static u64 nfsd_foreach_client_open(struct nfs4_client *clp, u64 max, void (*func)(struct nfs4_openowner *))
 {
 	struct nfs4_openowner *oop, *next;
@@ -4657,6 +4680,13 @@ u64 nfsd_forget_client_openowners(struct nfs4_client *clp, u64 max)
 	return nfsd_foreach_client_open(clp, max, release_openowner);
 }
 
+u64 nfsd_print_client_openowners(struct nfs4_client *clp, u64 max)
+{
+	u64 count = nfsd_foreach_client_open(clp, max, NULL);
+	nfsd_print_count(clp, count, "open files");
+	return count;
+}
+
 static u64 nfsd_find_all_delegations(struct nfs4_client *clp, u64 max,
 				     struct list_head *victims)
 {
@@ -4703,6 +4733,18 @@ u64 nfsd_recall_client_delegations(struct nfs4_client *clp, u64 max)
 	return count;
 }
 
+u64 nfsd_print_client_delegations(struct nfs4_client *clp, u64 max)
+{
+	u64 count = 0;
+
+	spin_lock(&recall_lock);
+	count = nfsd_find_all_delegations(clp, max, NULL);
+	spin_unlock(&recall_lock);
+
+	nfsd_print_count(clp, count, "delegations");
+	return count;
+}
+
 u64 nfsd_for_n_state(u64 max, u64 (*func)(struct nfs4_client *, u64))
 {
 	struct nfs4_client *clp, *next;

fs/nfsd/state.h

@@ -508,6 +508,11 @@ u64 nfsd_forget_client_locks(struct nfs4_client*, u64);
 u64 nfsd_forget_client_openowners(struct nfs4_client *, u64);
 u64 nfsd_forget_client_delegations(struct nfs4_client *, u64);
 u64 nfsd_recall_client_delegations(struct nfs4_client *, u64);
+
+u64 nfsd_print_client(struct nfs4_client *, u64);
+u64 nfsd_print_client_locks(struct nfs4_client *, u64);
+u64 nfsd_print_client_openowners(struct nfs4_client *, u64);
+u64 nfsd_print_client_delegations(struct nfs4_client *, u64);
 #else /* CONFIG_NFSD_FAULT_INJECTION */
 static inline int nfsd_fault_inject_init(void) { return 0; }
 static inline void nfsd_fault_inject_cleanup(void) {}