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, 6 insertions, 4 deletions

diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c
index 181317126e43..2603db03b7ff 100644
--- a/fs/afs/rxrpc.c
+++ b/fs/afs/rxrpc.c
@@ -296,7 +296,8 @@ static void afs_notify_end_request_tx(struct sock *sock,
  */
 void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp)
 {
-	struct sockaddr_rxrpc *srx = &ac->alist->addrs[ac->index].srx;
+	struct afs_address *addr = &ac->alist->addrs[ac->index];
+	struct rxrpc_peer *peer = addr->peer;
 	struct rxrpc_call *rxcall;
 	struct msghdr msg;
 	struct kvec iov[1];
@@ -304,7 +305,7 @@ void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp)
 	s64 tx_total_len;
 	int ret;
 
-	_enter(",{%pISp},", &srx->transport);
+	_enter(",{%pISp},", rxrpc_kernel_remote_addr(addr->peer));
 
 	ASSERT(call->type != NULL);
 	ASSERT(call->type->name != NULL);
@@ -333,7 +334,7 @@ void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp)
 	}
 
 	/* create a call */
-	rxcall = rxrpc_kernel_begin_call(call->net->socket, srx, call->key,
+	rxcall = rxrpc_kernel_begin_call(call->net->socket, peer, call->key,
 					 (unsigned long)call,
 					 tx_total_len,
 					 call->max_lifespan,
@@ -341,6 +342,7 @@ void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp)
 					 (call->async ?
 					  afs_wake_up_async_call :
 					  afs_wake_up_call_waiter),
+					 addr->service_id,
 					 call->upgrade,
 					 (call->intr ? RXRPC_PREINTERRUPTIBLE :
 					  RXRPC_UNINTERRUPTIBLE),
@@ -461,7 +463,7 @@ static void afs_log_error(struct afs_call *call, s32 remote_abort)
 		max = m + 1;
 		pr_notice("kAFS: Peer reported %s failure on %s [%pISp]\n",
 			  msg, call->type->name,
-			  &call->alist->addrs[call->addr_ix].srx.transport);
+			  rxrpc_kernel_remote_addr(call->alist->addrs[call->addr_ix].peer));
 	}
 }