diff options
author | David Howells <dhowells@redhat.com> | 2016-04-04 14:00:35 +0100 |
---|---|---|
committer | David Howells <dhowells@redhat.com> | 2016-06-15 15:38:17 +0100 |
commit | 4f95dd78a77edc42454de55bb32332be293fb461 (patch) | |
tree | 45e369bc5cb6fdbdd96cf8169d069ee9a75d1994 /net/rxrpc/call_accept.c | |
parent | 875636163b4e694c092625ed98b17e10d582b3ca (diff) | |
download | linux-4f95dd78a77edc42454de55bb32332be293fb461.tar.bz2 |
rxrpc: Rework local endpoint management
Rework the local RxRPC endpoint management.
Local endpoint objects are maintained in a flat list as before. This
should be okay as there shouldn't be more than one per open AF_RXRPC socket
(there can be fewer as local endpoints can be shared if their local service
ID is 0 and they share the same local transport parameters).
Changes:
(1) Local endpoints may now only be shared if they have local service ID 0
(ie. they're not being used for listening).
This prevents a scenario where process A is listening of the Cache
Manager port and process B contacts a fileserver - which may then
attempt to send CM requests back to B. But if A and B are sharing a
local endpoint, A will get the CM requests meant for B.
(2) We use a mutex to handle lookups and don't provide RCU-only lookups
since we only expect to access the list when opening a socket or
destroying an endpoint.
The local endpoint object is pointed to by the transport socket's
sk_user_data for the life of the transport socket - allowing us to
refer to it directly from the sk_data_ready and sk_error_report
callbacks.
(3) atomic_inc_not_zero() now exists and can be used to only share a local
endpoint if the last reference hasn't yet gone.
(4) We can remove rxrpc_local_lock - a spinlock that had to be taken with
BH processing disabled given that we assume sk_user_data won't change
under us.
(5) The transport socket is shut down before we clear the sk_user_data
pointer so that we can be sure that the transport socket's callbacks
won't be invoked once the RCU destruction is scheduled.
(6) Local endpoints have a work item that handles both destruction and
event processing. The means that destruction doesn't then need to
wait for event processing. The event queues can then be cleared after
the transport socket is shut down.
(7) Local endpoints are no longer available for resurrection beyond the
life of the sockets that had them open. As soon as their last ref
goes, they are scheduled for destruction and may not have their usage
count moved from 0.
Signed-off-by: David Howells <dhowells@redhat.com>
Diffstat (limited to 'net/rxrpc/call_accept.c')
-rw-r--r-- | net/rxrpc/call_accept.c | 25 |
1 files changed, 5 insertions, 20 deletions
diff --git a/net/rxrpc/call_accept.c b/net/rxrpc/call_accept.c index e5723f4dce89..50136c76ebd1 100644 --- a/net/rxrpc/call_accept.c +++ b/net/rxrpc/call_accept.c @@ -202,10 +202,8 @@ error_nofree: * accept incoming calls that need peer, transport and/or connection setting up * - the packets we get are all incoming client DATA packets that have seq == 1 */ -void rxrpc_accept_incoming_calls(struct work_struct *work) +void rxrpc_accept_incoming_calls(struct rxrpc_local *local) { - struct rxrpc_local *local = - container_of(work, struct rxrpc_local, acceptor); struct rxrpc_skb_priv *sp; struct sockaddr_rxrpc srx; struct rxrpc_sock *rx; @@ -215,21 +213,8 @@ void rxrpc_accept_incoming_calls(struct work_struct *work) _enter("%d", local->debug_id); - read_lock_bh(&rxrpc_local_lock); - if (atomic_read(&local->usage) > 0) - rxrpc_get_local(local); - else - local = NULL; - read_unlock_bh(&rxrpc_local_lock); - if (!local) { - _leave(" [local dead]"); - return; - } - -process_next_packet: skb = skb_dequeue(&local->accept_queue); if (!skb) { - rxrpc_put_local(local); _leave("\n"); return; } @@ -292,7 +277,7 @@ found_service: case -ECONNRESET: /* old calls are ignored */ case -ECONNABORTED: /* aborted calls are reaborted or ignored */ case 0: - goto process_next_packet; + return; case -ECONNREFUSED: goto invalid_service; case -EBUSY: @@ -308,18 +293,18 @@ backlog_full: busy: rxrpc_busy(local, &srx, &whdr); rxrpc_free_skb(skb); - goto process_next_packet; + return; invalid_service: skb->priority = RX_INVALID_OPERATION; rxrpc_reject_packet(local, skb); - goto process_next_packet; + return; /* can't change connection security type mid-flow */ security_mismatch: skb->priority = RX_PROTOCOL_ERROR; rxrpc_reject_packet(local, skb); - goto process_next_packet; + return; } /* |