rxrpc: Remove deadcode

Remove three functions that are no longer used.

rxrpc_get_txbuf() last use was removed by 2020's
commit 5e6ef4f1017c ("rxrpc: Make the I/O thread take over the call and
local processor work")

rxrpc_kernel_get_epoch() last use was removed by 2020's
commit 44746355ccb1 ("afs: Don't get epoch from a server because it may be
ambiguous")

rxrpc_kernel_set_max_life() last use was removed by 2023's
commit db099c625b13 ("rxrpc: Fix timeout of a call that hasn't yet been
granted a channel")

Both of the rxrpc_kernel_* functions were documented. Remove that
documentation as well as the code.

Signed-off-by: Dr. David Alan Gilbert <[e-mail]>
Acked-by: David Howells <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

Documentation/networking/rxrpc.rst

···
      first function to change.  Note that this must be called in TASK_RUNNING
      state.
 
- (#) Get remote client epoch::
-
-	u32 rxrpc_kernel_get_epoch(struct socket *sock,
-				   struct rxrpc_call *call)
-
-     This allows the epoch that's contained in packets of an incoming client
-     call to be queried.  This value is returned.  The function always
-     successful if the call is still in progress.  It shouldn't be called once
-     the call has expired.  Note that calling this on a local client call only
-     returns the local epoch.
-
-     This value can be used to determine if the remote client has been
-     restarted as it shouldn't change otherwise.
-
- (#) Set the maximum lifespan on a call::
-
-	void rxrpc_kernel_set_max_life(struct socket *sock,
-				       struct rxrpc_call *call,
-				       unsigned long hard_timeout)
-
-     This sets the maximum lifespan on a call to hard_timeout (which is in
-     jiffies).  In the event of the timeout occurring, the call will be
-     aborted and -ETIME or -ETIMEDOUT will be returned.
-
  (#) Apply the RXRPC_MIN_SECURITY_LEVEL sockopt to a socket from within in the
      kernel::
 

include/net/af_rxrpc.h

···
 			       unsigned int debug_id);
 void rxrpc_kernel_set_tx_length(struct socket *, struct rxrpc_call *, s64);
 bool rxrpc_kernel_check_life(const struct socket *, const struct rxrpc_call *);
-u32 rxrpc_kernel_get_epoch(struct socket *, struct rxrpc_call *);
-void rxrpc_kernel_set_max_life(struct socket *, struct rxrpc_call *,
-			       unsigned long);
 
 int rxrpc_sock_set_min_security_level(struct sock *sk, unsigned int val);
 int rxrpc_sock_set_security_keyring(struct sock *, struct key *);

net/rxrpc/af_rxrpc.c

···
 EXPORT_SYMBOL(rxrpc_kernel_check_life);
 
 /**
- * rxrpc_kernel_get_epoch - Retrieve the epoch value from a call.
- * @sock: The socket the call is on
- * @call: The call to query
- *
- * Allow a kernel service to retrieve the epoch value from a service call to
- * see if the client at the other end rebooted.
- *
- * Return: The epoch of the call's connection.
- */
-u32 rxrpc_kernel_get_epoch(struct socket *sock, struct rxrpc_call *call)
-{
-	return call->conn->proto.epoch;
-}
-EXPORT_SYMBOL(rxrpc_kernel_get_epoch);
-
-/**
  * rxrpc_kernel_set_notifications - Set table of callback operations
  * @sock: The socket to install table upon
  * @app_ops: Callback operation table to set
···
 	rx->app_ops = app_ops;
 }
 EXPORT_SYMBOL(rxrpc_kernel_set_notifications);
-
-/**
- * rxrpc_kernel_set_max_life - Set maximum lifespan on a call
- * @sock: The socket the call is on
- * @call: The call to configure
- * @hard_timeout: The maximum lifespan of the call in ms
- *
- * Set the maximum lifespan of a call.  The call will end with ETIME or
- * ETIMEDOUT if it takes longer than this.
- */
-void rxrpc_kernel_set_max_life(struct socket *sock, struct rxrpc_call *call,
-			       unsigned long hard_timeout)
-{
-	ktime_t delay = ms_to_ktime(hard_timeout), expect_term_by;
-
-	mutex_lock(&call->user_mutex);
-
-	expect_term_by = ktime_add(ktime_get_real(), delay);
-	WRITE_ONCE(call->expect_term_by, expect_term_by);
-	trace_rxrpc_timer_set(call, delay, rxrpc_timer_trace_hard);
-	rxrpc_poke_call(call, rxrpc_call_poke_set_timeout);
-
-	mutex_unlock(&call->user_mutex);
-}
-EXPORT_SYMBOL(rxrpc_kernel_set_max_life);
 
 /*
  * connect an RxRPC socket

net/rxrpc/ar-internal.h

···
 extern atomic_t rxrpc_nr_txbuf;
 struct rxrpc_txbuf *rxrpc_alloc_data_txbuf(struct rxrpc_call *call, size_t data_size,
 					   size_t data_align, gfp_t gfp);
-void rxrpc_get_txbuf(struct rxrpc_txbuf *txb, enum rxrpc_txbuf_trace what);
 void rxrpc_see_txbuf(struct rxrpc_txbuf *txb, enum rxrpc_txbuf_trace what);
 void rxrpc_put_txbuf(struct rxrpc_txbuf *txb, enum rxrpc_txbuf_trace what);
 

net/rxrpc/txbuf.c

···
 	return txb;
 }
 
-void rxrpc_get_txbuf(struct rxrpc_txbuf *txb, enum rxrpc_txbuf_trace what)
-{
-	int r;
-
-	__refcount_inc(&txb->ref, &r);
-	trace_rxrpc_txbuf(txb->debug_id, txb->call_debug_id, txb->seq, r + 1, what);
-}
-
 void rxrpc_see_txbuf(struct rxrpc_txbuf *txb, enum rxrpc_txbuf_trace what)
 {
 	int r = refcount_read(&txb->ref);