5 files changed, 56 insertions, 7 deletions

diff --git a/include/linux/sunrpc/bc_xprt.h b/include/linux/sunrpc/bc_xprt.h
index 2ca67b55e0fe..8df43c9f11dc 100644
--- a/include/linux/sunrpc/bc_xprt.h
+++ b/include/linux/sunrpc/bc_xprt.h
@@ -37,7 +37,6 @@ void xprt_complete_bc_request(struct rpc_rqst *req, uint32_t copied);
 void xprt_free_bc_request(struct rpc_rqst *req);
 int xprt_setup_backchannel(struct rpc_xprt *, unsigned int min_reqs);
 void xprt_destroy_backchannel(struct rpc_xprt *, unsigned int max_reqs);
-int bc_send(struct rpc_rqst *req);
 
 /*
  * Determine if a shared backchannel is in use
diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index 598ba80ec30c..131032f15cc1 100644
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -56,6 +56,7 @@ struct rpc_clnt {
 	struct rpc_rtt *	cl_rtt;		/* RTO estimator data */
 	const struct rpc_timeout *cl_timeout;	/* Timeout strategy */
 
+	atomic_t		cl_swapper;	/* swapfile count */
 	int			cl_nodelen;	/* nodename length */
 	char 			cl_nodename[UNX_MAXNODENAME+1];
 	struct rpc_pipe_dir_head cl_pipedir_objects;
diff --git a/include/linux/sunrpc/sched.h b/include/linux/sunrpc/sched.h
index 5f1e6bd4c316..d703f0ef37d8 100644
--- a/include/linux/sunrpc/sched.h
+++ b/include/linux/sunrpc/sched.h
@@ -205,8 +205,7 @@ struct rpc_wait_queue {
  */
 struct rpc_task *rpc_new_task(const struct rpc_task_setup *);
 struct rpc_task *rpc_run_task(const struct rpc_task_setup *);
-struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
-				const struct rpc_call_ops *ops);
+struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req);
 void		rpc_put_task(struct rpc_task *);
 void		rpc_put_task_async(struct rpc_task *);
 void		rpc_exit_task(struct rpc_task *);
@@ -269,4 +268,20 @@ static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
 }
 #endif
 
+#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
+int rpc_clnt_swap_activate(struct rpc_clnt *clnt);
+void rpc_clnt_swap_deactivate(struct rpc_clnt *clnt);
+#else
+static inline int
+rpc_clnt_swap_activate(struct rpc_clnt *clnt)
+{
+	return -EINVAL;
+}
+
+static inline void
+rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
+{
+}
+#endif /* CONFIG_SUNRPC_SWAP */
+
 #endif /* _LINUX_SUNRPC_SCHED_H_ */
diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index 8b93ef53df3c..0fb9acbb4780 100644
--- a/include/linux/sunrpc/xprt.h
+++ b/include/linux/sunrpc/xprt.h
@@ -133,6 +133,9 @@ struct rpc_xprt_ops {
 	void		(*close)(struct rpc_xprt *xprt);
 	void		(*destroy)(struct rpc_xprt *xprt);
 	void		(*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq);
+	int		(*enable_swap)(struct rpc_xprt *xprt);
+	void		(*disable_swap)(struct rpc_xprt *xprt);
+	void		(*inject_disconnect)(struct rpc_xprt *xprt);
 };
 
 /*
@@ -180,7 +183,7 @@ struct rpc_xprt {
 	atomic_t		num_reqs;	/* total slots */
 	unsigned long		state;		/* transport state */
 	unsigned char		resvport   : 1; /* use a reserved port */
-	unsigned int		swapper;	/* we're swapping over this
+	atomic_t		swapper;	/* we're swapping over this
 						   transport */
 	unsigned int		bind_index;	/* bind function index */
 
@@ -212,7 +215,8 @@ struct rpc_xprt {
 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 	struct svc_serv		*bc_serv;       /* The RPC service which will */
 						/* process the callback */
-	unsigned int		bc_alloc_count;	/* Total number of preallocs */
+	int			bc_alloc_count;	/* Total number of preallocs */
+	atomic_t		bc_free_slots;
 	spinlock_t		bc_pa_lock;	/* Protects the preallocated
 						 * items */
 	struct list_head	bc_pa_list;	/* List of preallocated
@@ -241,6 +245,7 @@ struct rpc_xprt {
 	const char		*address_strings[RPC_DISPLAY_MAX];
 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 	struct dentry		*debugfs;		/* debugfs directory */
+	atomic_t		inject_disconnect;
 #endif
 };
 
@@ -327,6 +332,18 @@ static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *
 	return p + xprt->tsh_size;
 }
 
+static inline int
+xprt_enable_swap(struct rpc_xprt *xprt)
+{
+	return xprt->ops->enable_swap(xprt);
+}
+
+static inline void
+xprt_disable_swap(struct rpc_xprt *xprt)
+{
+	xprt->ops->disable_swap(xprt);
+}
+
 /*
  * Transport switch helper functions
  */
@@ -345,7 +362,6 @@ void			xprt_release_rqst_cong(struct rpc_task *task);
 void			xprt_disconnect_done(struct rpc_xprt *xprt);
 void			xprt_force_disconnect(struct rpc_xprt *xprt);
 void			xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie);
-int			xs_swapper(struct rpc_xprt *xprt, int enable);
 
 bool			xprt_lock_connect(struct rpc_xprt *, struct rpc_task *, void *);
 void			xprt_unlock_connect(struct rpc_xprt *, void *);
@@ -431,6 +447,23 @@ static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
 	return test_and_set_bit(XPRT_BINDING, &xprt->state);
 }
 
+#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
+extern unsigned int rpc_inject_disconnect;
+static inline void xprt_inject_disconnect(struct rpc_xprt *xprt)
+{
+	if (!rpc_inject_disconnect)
+		return;
+	if (atomic_dec_return(&xprt->inject_disconnect))
+		return;
+	atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect);
+	xprt->ops->inject_disconnect(xprt);
+}
+#else
+static inline void xprt_inject_disconnect(struct rpc_xprt *xprt)
+{
+}
+#endif
+
 #endif /* __KERNEL__*/
 
 #endif /* _LINUX_SUNRPC_XPRT_H */
diff --git a/include/linux/sunrpc/xprtrdma.h b/include/linux/sunrpc/xprtrdma.h
index c984c85981ea..b17613052cc3 100644
--- a/include/linux/sunrpc/xprtrdma.h
+++ b/include/linux/sunrpc/xprtrdma.h
@@ -56,7 +56,8 @@
 
 #define RPCRDMA_INLINE_PAD_THRESH  (512)/* payload threshold to pad (bytes) */
 
-/* memory registration strategies */
+/* Memory registration strategies, by number.
+ * This is part of a kernel / user space API. Do not remove. */
 enum rpcrdma_memreg {
 	RPCRDMA_BOUNCEBUFFERS = 0,
 	RPCRDMA_REGISTER,