diff options
Diffstat (limited to 'net/rxrpc/conn_object.c')
-rw-r--r-- | net/rxrpc/conn_object.c | 552 |
1 files changed, 197 insertions, 355 deletions
diff --git a/net/rxrpc/conn_object.c b/net/rxrpc/conn_object.c index 1754f2e2e16b..276ff505394f 100644 --- a/net/rxrpc/conn_object.c +++ b/net/rxrpc/conn_object.c @@ -32,152 +32,6 @@ DEFINE_RWLOCK(rxrpc_connection_lock); static DECLARE_DELAYED_WORK(rxrpc_connection_reap, rxrpc_connection_reaper); /* - * allocate a new client connection bundle - */ -static struct rxrpc_conn_bundle *rxrpc_alloc_bundle(gfp_t gfp) -{ - struct rxrpc_conn_bundle *bundle; - - _enter(""); - - bundle = kzalloc(sizeof(struct rxrpc_conn_bundle), gfp); - if (bundle) { - INIT_LIST_HEAD(&bundle->unused_conns); - INIT_LIST_HEAD(&bundle->avail_conns); - INIT_LIST_HEAD(&bundle->busy_conns); - init_waitqueue_head(&bundle->chanwait); - atomic_set(&bundle->usage, 1); - } - - _leave(" = %p", bundle); - return bundle; -} - -/* - * compare bundle parameters with what we're looking for - * - return -ve, 0 or +ve - */ -static inline -int rxrpc_cmp_bundle(const struct rxrpc_conn_bundle *bundle, - struct key *key, u16 service_id) -{ - return (bundle->service_id - service_id) ?: - ((unsigned long)bundle->key - (unsigned long)key); -} - -/* - * get bundle of client connections that a client socket can make use of - */ -struct rxrpc_conn_bundle *rxrpc_get_bundle(struct rxrpc_sock *rx, - struct rxrpc_transport *trans, - struct key *key, - u16 service_id, - gfp_t gfp) -{ - struct rxrpc_conn_bundle *bundle, *candidate; - struct rb_node *p, *parent, **pp; - - _enter("%p{%x},%x,%hx,", - rx, key_serial(key), trans->debug_id, service_id); - - /* search the extant bundles first for one that matches the specified - * user ID */ - spin_lock(&trans->client_lock); - - p = trans->bundles.rb_node; - while (p) { - bundle = rb_entry(p, struct rxrpc_conn_bundle, node); - - if (rxrpc_cmp_bundle(bundle, key, service_id) < 0) - p = p->rb_left; - else if (rxrpc_cmp_bundle(bundle, key, service_id) > 0) - p = p->rb_right; - else - goto found_extant_bundle; - } - - spin_unlock(&trans->client_lock); - - /* not yet present - create a candidate for a new record and then - * redo the search */ - candidate = rxrpc_alloc_bundle(gfp); - if (!candidate) { - _leave(" = -ENOMEM"); - return ERR_PTR(-ENOMEM); - } - - candidate->key = key_get(key); - candidate->service_id = service_id; - - spin_lock(&trans->client_lock); - - pp = &trans->bundles.rb_node; - parent = NULL; - while (*pp) { - parent = *pp; - bundle = rb_entry(parent, struct rxrpc_conn_bundle, node); - - if (rxrpc_cmp_bundle(bundle, key, service_id) < 0) - pp = &(*pp)->rb_left; - else if (rxrpc_cmp_bundle(bundle, key, service_id) > 0) - pp = &(*pp)->rb_right; - else - goto found_extant_second; - } - - /* second search also failed; add the new bundle */ - bundle = candidate; - candidate = NULL; - - rb_link_node(&bundle->node, parent, pp); - rb_insert_color(&bundle->node, &trans->bundles); - spin_unlock(&trans->client_lock); - _net("BUNDLE new on trans %d", trans->debug_id); - _leave(" = %p [new]", bundle); - return bundle; - - /* we found the bundle in the list immediately */ -found_extant_bundle: - atomic_inc(&bundle->usage); - spin_unlock(&trans->client_lock); - _net("BUNDLE old on trans %d", trans->debug_id); - _leave(" = %p [extant %d]", bundle, atomic_read(&bundle->usage)); - return bundle; - - /* we found the bundle on the second time through the list */ -found_extant_second: - atomic_inc(&bundle->usage); - spin_unlock(&trans->client_lock); - kfree(candidate); - _net("BUNDLE old2 on trans %d", trans->debug_id); - _leave(" = %p [second %d]", bundle, atomic_read(&bundle->usage)); - return bundle; -} - -/* - * release a bundle - */ -void rxrpc_put_bundle(struct rxrpc_transport *trans, - struct rxrpc_conn_bundle *bundle) -{ - _enter("%p,%p{%d}",trans, bundle, atomic_read(&bundle->usage)); - - if (atomic_dec_and_lock(&bundle->usage, &trans->client_lock)) { - _debug("Destroy bundle"); - rb_erase(&bundle->node, &trans->bundles); - spin_unlock(&trans->client_lock); - ASSERT(list_empty(&bundle->unused_conns)); - ASSERT(list_empty(&bundle->avail_conns)); - ASSERT(list_empty(&bundle->busy_conns)); - ASSERTCMP(bundle->num_conns, ==, 0); - key_put(bundle->key); - kfree(bundle); - } - - _leave(""); -} - -/* * allocate a new connection */ static struct rxrpc_connection *rxrpc_alloc_connection(gfp_t gfp) @@ -188,8 +42,10 @@ static struct rxrpc_connection *rxrpc_alloc_connection(gfp_t gfp) conn = kzalloc(sizeof(struct rxrpc_connection), gfp); if (conn) { + spin_lock_init(&conn->channel_lock); + init_waitqueue_head(&conn->channel_wq); INIT_WORK(&conn->processor, &rxrpc_process_connection); - INIT_LIST_HEAD(&conn->bundle_link); + INIT_LIST_HEAD(&conn->link); conn->calls = RB_ROOT; skb_queue_head_init(&conn->rx_queue); conn->security = &rxrpc_no_security; @@ -197,7 +53,7 @@ static struct rxrpc_connection *rxrpc_alloc_connection(gfp_t gfp) spin_lock_init(&conn->state_lock); atomic_set(&conn->usage, 1); conn->debug_id = atomic_inc_return(&rxrpc_debug_id); - conn->avail_calls = RXRPC_MAXCALLS; + atomic_set(&conn->avail_chans, RXRPC_MAXCALLS); conn->size_align = 4; conn->header_size = sizeof(struct rxrpc_wire_header); } @@ -240,7 +96,8 @@ static void rxrpc_add_call_ID_to_conn(struct rxrpc_connection *conn, } /* - * Allocate a client connection. + * Allocate a client connection. The caller must take care to clear any + * padding bytes in *cp. */ static struct rxrpc_connection * rxrpc_alloc_client_connection(struct rxrpc_conn_parameters *cp, @@ -275,7 +132,7 @@ rxrpc_alloc_client_connection(struct rxrpc_conn_parameters *cp, break; } - ret = rxrpc_get_client_connection_id(conn, trans, gfp); + ret = rxrpc_get_client_connection_id(conn, gfp); if (ret < 0) goto error_0; @@ -290,6 +147,8 @@ rxrpc_alloc_client_connection(struct rxrpc_conn_parameters *cp, write_unlock(&rxrpc_connection_lock); key_get(conn->params.key); + conn->trans = trans; + atomic_inc(&trans->usage); _leave(" = %p", conn); return conn; @@ -303,217 +162,173 @@ error_0: } /* - * connect a call on an exclusive connection - */ -static int rxrpc_connect_exclusive(struct rxrpc_sock *rx, - struct rxrpc_conn_parameters *cp, - struct rxrpc_transport *trans, - struct rxrpc_call *call, - gfp_t gfp) -{ - struct rxrpc_connection *conn; - int chan; - - _enter(""); - - conn = rxrpc_alloc_client_connection(cp, trans, gfp); - if (IS_ERR(conn)) { - _leave(" = %ld", PTR_ERR(conn)); - return PTR_ERR(conn); - } - - atomic_inc(&trans->usage); - conn->trans = trans; - conn->bundle = NULL; - - _net("CONNECT EXCL new %d on TRANS %d", - conn->debug_id, conn->trans->debug_id); - - /* Since no one else can use the connection, we just use the first - * channel. - */ - chan = 0; - rxrpc_get_connection(conn); - conn->avail_calls = RXRPC_MAXCALLS - 1; - conn->channels[chan] = call; - conn->call_counter = 1; - call->conn = conn; - call->channel = chan; - call->cid = conn->proto.cid | chan; - call->call_id = 1; - - _net("CONNECT client on conn %d chan %d as call %x", - conn->debug_id, chan, call->call_id); - - rxrpc_add_call_ID_to_conn(conn, call); - _leave(" = 0"); - return 0; -} - -/* * find a connection for a call * - called in process context with IRQs enabled */ -int rxrpc_connect_call(struct rxrpc_sock *rx, +int rxrpc_connect_call(struct rxrpc_call *call, struct rxrpc_conn_parameters *cp, struct rxrpc_transport *trans, - struct rxrpc_conn_bundle *bundle, - struct rxrpc_call *call, + struct sockaddr_rxrpc *srx, gfp_t gfp) { - struct rxrpc_connection *conn, *candidate; + struct rxrpc_connection *conn, *candidate = NULL; + struct rxrpc_local *local = cp->local; + struct rb_node *p, **pp, *parent; + long diff; int chan; DECLARE_WAITQUEUE(myself, current); - _enter("%p,%lx,", rx, call->user_call_ID); - - if (cp->exclusive) - return rxrpc_connect_exclusive(rx, cp, trans, call, gfp); - - spin_lock(&trans->client_lock); - for (;;) { - /* see if the bundle has a call slot available */ - if (!list_empty(&bundle->avail_conns)) { - _debug("avail"); - conn = list_entry(bundle->avail_conns.next, - struct rxrpc_connection, - bundle_link); - if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) { - list_del_init(&conn->bundle_link); - bundle->num_conns--; - continue; - } - if (--conn->avail_calls == 0) - list_move(&conn->bundle_link, - &bundle->busy_conns); - ASSERTCMP(conn->avail_calls, <, RXRPC_MAXCALLS); - ASSERT(conn->channels[0] == NULL || - conn->channels[1] == NULL || - conn->channels[2] == NULL || - conn->channels[3] == NULL); - rxrpc_get_connection(conn); - break; - } + _enter("{%d,%lx},", call->debug_id, call->user_call_ID); - if (!list_empty(&bundle->unused_conns)) { - _debug("unused"); - conn = list_entry(bundle->unused_conns.next, - struct rxrpc_connection, - bundle_link); - if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) { - list_del_init(&conn->bundle_link); - bundle->num_conns--; - continue; - } - ASSERTCMP(conn->avail_calls, ==, RXRPC_MAXCALLS); - conn->avail_calls = RXRPC_MAXCALLS - 1; - ASSERT(conn->channels[0] == NULL && - conn->channels[1] == NULL && - conn->channels[2] == NULL && - conn->channels[3] == NULL); - rxrpc_get_connection(conn); - list_move(&conn->bundle_link, &bundle->avail_conns); - break; + cp->peer = trans->peer; + rxrpc_get_peer(cp->peer); + + if (!cp->exclusive) { + /* Search for a existing client connection unless this is going + * to be a connection that's used exclusively for a single call. + */ + _debug("search 1"); + spin_lock(&local->client_conns_lock); + p = local->client_conns.rb_node; + while (p) { + conn = rb_entry(p, struct rxrpc_connection, client_node); + +#define cmp(X) ((long)conn->params.X - (long)cp->X) + diff = (cmp(peer) ?: + cmp(key) ?: + cmp(security_level)); + if (diff < 0) + p = p->rb_left; + else if (diff > 0) + p = p->rb_right; + else + goto found_extant_conn; } + spin_unlock(&local->client_conns_lock); + } - /* need to allocate a new connection */ - _debug("get new conn [%d]", bundle->num_conns); + /* We didn't find a connection or we want an exclusive one. */ + _debug("get new conn"); + candidate = rxrpc_alloc_client_connection(cp, trans, gfp); + if (!candidate) { + _leave(" = -ENOMEM"); + return -ENOMEM; + } - spin_unlock(&trans->client_lock); + if (cp->exclusive) { + /* Assign the call on an exclusive connection to channel 0 and + * don't add the connection to the endpoint's shareable conn + * lookup tree. + */ + _debug("exclusive chan 0"); + conn = candidate; + atomic_set(&conn->avail_chans, RXRPC_MAXCALLS - 1); + spin_lock(&conn->channel_lock); + chan = 0; + goto found_channel; + } - if (signal_pending(current)) - goto interrupted; + /* We need to redo the search before attempting to add a new connection + * lest we race with someone else adding a conflicting instance. + */ + _debug("search 2"); + spin_lock(&local->client_conns_lock); - if (bundle->num_conns >= 20) { - _debug("too many conns"); + pp = &local->client_conns.rb_node; + parent = NULL; + while (*pp) { + parent = *pp; + conn = rb_entry(parent, struct rxrpc_connection, client_node); - if (!gfpflags_allow_blocking(gfp)) { - _leave(" = -EAGAIN"); - return -EAGAIN; - } + diff = (cmp(peer) ?: + cmp(key) ?: + cmp(security_level)); + if (diff < 0) + pp = &(*pp)->rb_left; + else if (diff > 0) + pp = &(*pp)->rb_right; + else + goto found_extant_conn; + } - add_wait_queue(&bundle->chanwait, &myself); - for (;;) { - set_current_state(TASK_INTERRUPTIBLE); - if (bundle->num_conns < 20 || - !list_empty(&bundle->unused_conns) || - !list_empty(&bundle->avail_conns)) - break; - if (signal_pending(current)) - goto interrupted_dequeue; - schedule(); - } - remove_wait_queue(&bundle->chanwait, &myself); - __set_current_state(TASK_RUNNING); - spin_lock(&trans->client_lock); - continue; - } + /* The second search also failed; simply add the new connection with + * the new call in channel 0. Note that we need to take the channel + * lock before dropping the client conn lock. + */ + _debug("new conn"); + conn = candidate; + candidate = NULL; - /* not yet present - create a candidate for a new connection and then - * redo the check */ - candidate = rxrpc_alloc_client_connection(cp, trans, gfp); - if (!candidate) { - _leave(" = -ENOMEM"); - return -ENOMEM; - } + rb_link_node(&conn->client_node, parent, pp); + rb_insert_color(&conn->client_node, &local->client_conns); + + atomic_set(&conn->avail_chans, RXRPC_MAXCALLS - 1); + spin_lock(&conn->channel_lock); + spin_unlock(&local->client_conns_lock); + chan = 0; + +found_channel: + _debug("found chan"); + call->conn = conn; + call->channel = chan; + call->epoch = conn->proto.epoch; + call->cid = conn->proto.cid | chan; + call->call_id = ++conn->call_counter; + rcu_assign_pointer(conn->channels[chan], call); - atomic_inc(&bundle->usage); - atomic_inc(&trans->usage); - candidate->trans = trans; - candidate->bundle = bundle; + _net("CONNECT call %d on conn %d", call->debug_id, conn->debug_id); - spin_lock(&trans->client_lock); + rxrpc_add_call_ID_to_conn(conn, call); + spin_unlock(&conn->channel_lock); + _leave(" = %p {u=%d}", conn, atomic_read(&conn->usage)); + return 0; + + /* We found a suitable connection already in existence. Discard any + * candidate we may have allocated, and try to get a channel on this + * one. + */ +found_extant_conn: + _debug("found conn"); + rxrpc_get_connection(conn); + spin_unlock(&local->client_conns_lock); - list_add(&candidate->bundle_link, &bundle->unused_conns); - bundle->num_conns++; + rxrpc_put_connection(candidate); - _net("CONNECT new %d on TRANS %d", - candidate->debug_id, candidate->trans->debug_id); + if (!atomic_add_unless(&conn->avail_chans, -1, 0)) { + if (!gfpflags_allow_blocking(gfp)) { + rxrpc_put_connection(conn); + _leave(" = -EAGAIN"); + return -EAGAIN; + } - /* leave the candidate lurking in zombie mode attached to the - * bundle until we're ready for it */ - rxrpc_put_connection(candidate); - candidate = NULL; + add_wait_queue(&conn->channel_wq, &myself); + for (;;) { + set_current_state(TASK_INTERRUPTIBLE); + if (atomic_add_unless(&conn->avail_chans, -1, 0)) + break; + if (signal_pending(current)) + goto interrupted; + schedule(); + } + remove_wait_queue(&conn->channel_wq, &myself); + __set_current_state(TASK_RUNNING); } - /* we've got a connection with a free channel and we can now attach the - * call to it - * - we're holding the transport's client lock - * - we're holding a reference on the connection - * - we're holding a reference on the bundle + /* The connection allegedly now has a free channel and we can now + * attach the call to it. */ + spin_lock(&conn->channel_lock); + for (chan = 0; chan < RXRPC_MAXCALLS; chan++) if (!conn->channels[chan]) goto found_channel; - ASSERT(conn->channels[0] == NULL || - conn->channels[1] == NULL || - conn->channels[2] == NULL || - conn->channels[3] == NULL); BUG(); -found_channel: - conn->channels[chan] = call; - call->conn = conn; - call->channel = chan; - call->cid = conn->proto.cid | chan; - call->call_id = ++conn->call_counter; - - _net("CONNECT client on conn %d chan %d as call %x", - conn->debug_id, chan, call->call_id); - - ASSERTCMP(conn->avail_calls, <, RXRPC_MAXCALLS); - spin_unlock(&trans->client_lock); - - rxrpc_add_call_ID_to_conn(conn, call); - - _leave(" = 0"); - return 0; - -interrupted_dequeue: - remove_wait_queue(&bundle->chanwait, &myself); - __set_current_state(TASK_RUNNING); interrupted: + remove_wait_queue(&conn->channel_wq, &myself); + __set_current_state(TASK_RUNNING); + rxrpc_put_connection(conn); _leave(" = -ERESTARTSYS"); return -ERESTARTSYS; } @@ -521,8 +336,8 @@ interrupted: /* * get a record of an incoming connection */ -struct rxrpc_connection * -rxrpc_incoming_connection(struct rxrpc_transport *trans, struct sk_buff *skb) +struct rxrpc_connection *rxrpc_incoming_connection(struct rxrpc_transport *trans, + struct sk_buff *skb) { struct rxrpc_connection *conn, *candidate = NULL; struct rxrpc_skb_priv *sp = rxrpc_skb(skb); @@ -543,7 +358,7 @@ rxrpc_incoming_connection(struct rxrpc_transport *trans, struct sk_buff *skb) p = trans->server_conns.rb_node; while (p) { - conn = rb_entry(p, struct rxrpc_connection, node); + conn = rb_entry(p, struct rxrpc_connection, service_node); _debug("maybe %x", conn->proto.cid); @@ -588,7 +403,7 @@ rxrpc_incoming_connection(struct rxrpc_transport *trans, struct sk_buff *skb) p = NULL; while (*pp) { p = *pp; - conn = rb_entry(p, struct rxrpc_connection, node); + conn = rb_entry(p, struct rxrpc_connection, service_node); if (epoch < conn->proto.epoch) pp = &(*pp)->rb_left; @@ -605,8 +420,8 @@ rxrpc_incoming_connection(struct rxrpc_transport *trans, struct sk_buff *skb) /* we can now add the new candidate to the list */ conn = candidate; candidate = NULL; - rb_link_node(&conn->node, p, pp); - rb_insert_color(&conn->node, &trans->server_conns); + rb_link_node(&conn->service_node, p, pp); + rb_insert_color(&conn->service_node, &trans->server_conns); atomic_inc(&conn->trans->usage); write_unlock_bh(&trans->conn_lock); @@ -672,7 +487,7 @@ struct rxrpc_connection *rxrpc_find_connection(struct rxrpc_transport *trans, if (sp->hdr.flags & RXRPC_CLIENT_INITIATED) { p = trans->server_conns.rb_node; while (p) { - conn = rb_entry(p, struct rxrpc_connection, node); + conn = rb_entry(p, struct rxrpc_connection, service_node); _debug("maybe %x", conn->proto.cid); @@ -705,10 +520,31 @@ found: } /* + * Disconnect a call and clear any channel it occupies when that call + * terminates. + */ +void rxrpc_disconnect_call(struct rxrpc_call *call) +{ + struct rxrpc_connection *conn = call->conn; + unsigned chan = call->channel; + + _enter("%d,%d", conn->debug_id, call->channel); + + if (conn->channels[chan] == call) { + rcu_assign_pointer(conn->channels[chan], NULL); + atomic_inc(&conn->avail_chans); + wake_up(&conn->channel_wq); + } +} + +/* * release a virtual connection */ void rxrpc_put_connection(struct rxrpc_connection *conn) { + if (!conn) + return; + _enter("%p{u=%d,d=%d}", conn, atomic_read(&conn->usage), conn->debug_id); @@ -734,9 +570,6 @@ static void rxrpc_destroy_connection(struct rxrpc_connection *conn) _net("DESTROY CONN %d", conn->debug_id); - if (conn->bundle) - rxrpc_put_bundle(conn->trans, conn->bundle); - ASSERT(RB_EMPTY_ROOT(&conn->calls)); rxrpc_purge_queue(&conn->rx_queue); @@ -773,30 +606,39 @@ static void rxrpc_connection_reaper(struct work_struct *work) if (likely(atomic_read(&conn->usage) > 0)) continue; - spin_lock(&conn->trans->client_lock); - write_lock_bh(&conn->trans->conn_lock); - reap_time = conn->put_time + rxrpc_connection_expiry; + if (rxrpc_conn_is_client(conn)) { + struct rxrpc_local *local = conn->params.local; + spin_lock(&local->client_conns_lock); + reap_time = conn->put_time + rxrpc_connection_expiry; - if (atomic_read(&conn->usage) > 0) { - ; - } else if (reap_time <= now) { - list_move_tail(&conn->link, &graveyard); - if (conn->out_clientflag) + if (atomic_read(&conn->usage) > 0) { + ; + } else if (reap_time <= now) { + list_move_tail(&conn->link, &graveyard); rxrpc_put_client_connection_id(conn); - else - rb_erase(&conn->node, + rb_erase(&conn->client_node, + &local->client_conns); + } else if (reap_time < earliest) { + earliest = reap_time; + } + + spin_unlock(&local->client_conns_lock); + } else { + write_lock_bh(&conn->trans->conn_lock); + reap_time = conn->put_time + rxrpc_connection_expiry; + + if (atomic_read(&conn->usage) > 0) { + ; + } else if (reap_time <= now) { + list_move_tail(&conn->link, &graveyard); + rb_erase(&conn->service_node, &conn->trans->server_conns); - if (conn->bundle) { - list_del_init(&conn->bundle_link); - conn->bundle->num_conns--; + } else if (reap_time < earliest) { + earliest = reap_time; } - } else if (reap_time < earliest) { - earliest = reap_time; + write_unlock_bh(&conn->trans->conn_lock); } - - write_unlock_bh(&conn->trans->conn_lock); - spin_unlock(&conn->trans->client_lock); } write_unlock(&rxrpc_connection_lock); |