SUNRPC: add xprt switch API for printing formatted remote peer addresses

Add a new method to the transport switch API to provide a way to convert
the opaque contents of xprt->addr to a human-readable string.

Test plan:
Compile kernel with CONFIG_NFS enabled.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index 84122559fa17..8372ab8fc9b5 100644
--- a/include/linux/sunrpc/xprt.h
+++ b/include/linux/sunrpc/xprt.h
@@ -51,6 +51,14 @@ struct rpc_timeout {
         unsigned char           to_exponential;
 };
 
+enum rpc_display_format_t {
+        RPC_DISPLAY_ADDR = 0,
+        RPC_DISPLAY_PORT,
+        RPC_DISPLAY_PROTO,
+        RPC_DISPLAY_ALL,
+        RPC_DISPLAY_MAX,
+};
+
 struct rpc_task;
 struct rpc_xprt;
 struct seq_file;
@@ -103,6 +111,7 @@ struct rpc_rqst {
 
 struct rpc_xprt_ops {
         void            (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize);
+        char *          (*print_addr)(struct rpc_xprt *xprt, enum rpc_display_format_t format);
         int             (*reserve_xprt)(struct rpc_task *task);
         void            (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
         void            (*rpcbind)(struct rpc_task *task);
@@ -207,6 +216,8 @@ struct rpc_xprt {
         void                    (*old_data_ready)(struct sock *, int);
         void                    (*old_state_change)(struct sock *);
         void                    (*old_write_space)(struct sock *);
+
+        char *                  address_strings[RPC_DISPLAY_MAX];
 };
 
 #define XPRT_LAST_FRAG          (1 << 0)