rxrpc, afs: Allow afs to pin rxrpc_peer objects

Change rxrpc's API such that:

 (1) A new function, rxrpc_kernel_lookup_peer(), is provided to look up an
     rxrpc_peer record for a remote address and a corresponding function,
     rxrpc_kernel_put_peer(), is provided to dispose of it again.

 (2) When setting up a call, the rxrpc_peer object used during a call is
     now passed in rather than being set up by rxrpc_connect_call().  For
     afs, this meenat passing it to rxrpc_kernel_begin_call() rather than
     the full address (the service ID then has to be passed in as a
     separate parameter).

 (3) A new function, rxrpc_kernel_remote_addr(), is added so that afs can
     get a pointer to the transport address for display purposed, and
     another, rxrpc_kernel_remote_srx(), to gain a pointer to the full
     rxrpc address.

 (4) The function to retrieve the RTT from a call, rxrpc_kernel_get_srtt(),
     is then altered to take a peer.  This now returns the RTT or -1 if
     there are insufficient samples.

 (5) Rename rxrpc_kernel_get_peer() to rxrpc_kernel_call_get_peer().

 (6) Provide a new function, rxrpc_kernel_get_peer(), to get a ref on a
     peer the caller already has.

This allows the afs filesystem to pin the rxrpc_peer records that it is
using, allowing faster lookups and pointer comparisons rather than
comparing sockaddr_rxrpc contents.  It also makes it easier to get hold of
the RTT.  The following changes are made to afs:

 (1) The addr_list struct's addrs[] elements now hold a peer struct pointer
     and a service ID rather than a sockaddr_rxrpc.

 (2) When displaying the transport address, rxrpc_kernel_remote_addr() is
     used.

 (3) The port arg is removed from afs_alloc_addrlist() since it's always
     overridden.

 (4) afs_merge_fs_addr4() and afs_merge_fs_addr6() do peer lookup and may
     now return an error that must be handled.

 (5) afs_find_server() now takes a peer pointer to specify the address.

 (6) afs_find_server(), afs_compare_fs_alists() and afs_merge_fs_addr[46]{}
     now do peer pointer comparison rather than address comparison.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org

1 files changed, 11 insertions, 4 deletions

diff --git a/include/net/af_rxrpc.h b/include/net/af_rxrpc.h
index 5531dd08061e..0754c463224a 100644
--- a/include/net/af_rxrpc.h
+++ b/include/net/af_rxrpc.h
@@ -15,6 +15,7 @@ struct key;
 struct sock;
 struct socket;
 struct rxrpc_call;
+struct rxrpc_peer;
 enum rxrpc_abort_reason;
 
 enum rxrpc_interruptibility {
@@ -41,13 +42,14 @@ void rxrpc_kernel_new_call_notification(struct socket *,
 					rxrpc_notify_new_call_t,
 					rxrpc_discard_new_call_t);
 struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
-					   struct sockaddr_rxrpc *srx,
+					   struct rxrpc_peer *peer,
 					   struct key *key,
 					   unsigned long user_call_ID,
 					   s64 tx_total_len,
 					   u32 hard_timeout,
 					   gfp_t gfp,
 					   rxrpc_notify_rx_t notify_rx,
+					   u16 service_id,
 					   bool upgrade,
 					   enum rxrpc_interruptibility interruptibility,
 					   unsigned int debug_id);
@@ -60,9 +62,14 @@ bool rxrpc_kernel_abort_call(struct socket *, struct rxrpc_call *,
 			     u32, int, enum rxrpc_abort_reason);
 void rxrpc_kernel_shutdown_call(struct socket *sock, struct rxrpc_call *call);
 void rxrpc_kernel_put_call(struct socket *sock, struct rxrpc_call *call);
-void rxrpc_kernel_get_peer(struct socket *, struct rxrpc_call *,
-			   struct sockaddr_rxrpc *);
-bool rxrpc_kernel_get_srtt(struct socket *, struct rxrpc_call *, u32 *);
+struct rxrpc_peer *rxrpc_kernel_lookup_peer(struct socket *sock,
+					    struct sockaddr_rxrpc *srx, gfp_t gfp);
+void rxrpc_kernel_put_peer(struct rxrpc_peer *peer);
+struct rxrpc_peer *rxrpc_kernel_get_peer(struct rxrpc_peer *peer);
+struct rxrpc_peer *rxrpc_kernel_get_call_peer(struct socket *sock, struct rxrpc_call *call);
+const struct sockaddr_rxrpc *rxrpc_kernel_remote_srx(const struct rxrpc_peer *peer);
+const struct sockaddr *rxrpc_kernel_remote_addr(const struct rxrpc_peer *peer);
+unsigned int rxrpc_kernel_get_srtt(const struct rxrpc_peer *);
 int rxrpc_kernel_charge_accept(struct socket *, rxrpc_notify_rx_t,
 			       rxrpc_user_attach_call_t, unsigned long, gfp_t,
 			       unsigned int);