X-Git-Url: http://git.cascardo.info/?a=blobdiff_plain;f=net%2Frxrpc%2Fcall_accept.c;h=832d854c2d5c409faa0e487ea9b3bac709d4031b;hb=6b5e09a748ad0a0b198d0e268c7e689044bfe48a;hp=9bae21e66d6547580a9d575a3569a9303d3cc7ea;hpb=33e09f0ee76e9e4108c5aed67e027ef5e3fe0634;p=cascardo%2Flinux.git diff --git a/net/rxrpc/call_accept.c b/net/rxrpc/call_accept.c index 9bae21e66d65..832d854c2d5c 100644 --- a/net/rxrpc/call_accept.c +++ b/net/rxrpc/call_accept.c @@ -20,265 +20,409 @@ #include #include #include +#include #include #include #include #include "ar-internal.h" /* - * generate a connection-level abort + * Preallocate a single service call, connection and peer and, if possible, + * give them a user ID and attach the user's side of the ID to them. */ -static int rxrpc_busy(struct rxrpc_local *local, struct sockaddr_rxrpc *srx, - struct rxrpc_wire_header *whdr) +static int rxrpc_service_prealloc_one(struct rxrpc_sock *rx, + struct rxrpc_backlog *b, + rxrpc_notify_rx_t notify_rx, + rxrpc_user_attach_call_t user_attach_call, + unsigned long user_call_ID, gfp_t gfp) { - struct msghdr msg; - struct kvec iov[1]; - size_t len; - int ret; + const void *here = __builtin_return_address(0); + struct rxrpc_call *call; + int max, tmp; + unsigned int size = RXRPC_BACKLOG_MAX; + unsigned int head, tail, call_head, call_tail; + + max = rx->sk.sk_max_ack_backlog; + tmp = rx->sk.sk_ack_backlog; + if (tmp >= max) { + _leave(" = -ENOBUFS [full %u]", max); + return -ENOBUFS; + } + max -= tmp; + + /* We don't need more conns and peers than we have calls, but on the + * other hand, we shouldn't ever use more peers than conns or conns + * than calls. + */ + call_head = b->call_backlog_head; + call_tail = READ_ONCE(b->call_backlog_tail); + tmp = CIRC_CNT(call_head, call_tail, size); + if (tmp >= max) { + _leave(" = -ENOBUFS [enough %u]", tmp); + return -ENOBUFS; + } + max = tmp + 1; + + head = b->peer_backlog_head; + tail = READ_ONCE(b->peer_backlog_tail); + if (CIRC_CNT(head, tail, size) < max) { + struct rxrpc_peer *peer = rxrpc_alloc_peer(rx->local, gfp); + if (!peer) + return -ENOMEM; + b->peer_backlog[head] = peer; + smp_store_release(&b->peer_backlog_head, + (head + 1) & (size - 1)); + } - _enter("%d,,", local->debug_id); + head = b->conn_backlog_head; + tail = READ_ONCE(b->conn_backlog_tail); + if (CIRC_CNT(head, tail, size) < max) { + struct rxrpc_connection *conn; - whdr->type = RXRPC_PACKET_TYPE_BUSY; - whdr->serial = htonl(1); + conn = rxrpc_prealloc_service_connection(gfp); + if (!conn) + return -ENOMEM; + b->conn_backlog[head] = conn; + smp_store_release(&b->conn_backlog_head, + (head + 1) & (size - 1)); - msg.msg_name = &srx->transport.sin; - msg.msg_namelen = sizeof(srx->transport.sin); - msg.msg_control = NULL; - msg.msg_controllen = 0; - msg.msg_flags = 0; + trace_rxrpc_conn(conn, rxrpc_conn_new_service, + atomic_read(&conn->usage), here); + } - iov[0].iov_base = whdr; - iov[0].iov_len = sizeof(*whdr); + /* Now it gets complicated, because calls get registered with the + * socket here, particularly if a user ID is preassigned by the user. + */ + call = rxrpc_alloc_call(gfp); + if (!call) + return -ENOMEM; + call->flags |= (1 << RXRPC_CALL_IS_SERVICE); + call->state = RXRPC_CALL_SERVER_PREALLOC; - len = iov[0].iov_len; + trace_rxrpc_call(call, rxrpc_call_new_service, + atomic_read(&call->usage), + here, (const void *)user_call_ID); - _proto("Tx BUSY %%1"); + write_lock(&rx->call_lock); + if (user_attach_call) { + struct rxrpc_call *xcall; + struct rb_node *parent, **pp; + + /* Check the user ID isn't already in use */ + pp = &rx->calls.rb_node; + parent = NULL; + while (*pp) { + parent = *pp; + xcall = rb_entry(parent, struct rxrpc_call, sock_node); + if (user_call_ID < call->user_call_ID) + pp = &(*pp)->rb_left; + else if (user_call_ID > call->user_call_ID) + pp = &(*pp)->rb_right; + else + goto id_in_use; + } - ret = kernel_sendmsg(local->socket, &msg, iov, 1, len); - if (ret < 0) { - _leave(" = -EAGAIN [sendmsg failed: %d]", ret); - return -EAGAIN; + call->user_call_ID = user_call_ID; + call->notify_rx = notify_rx; + rxrpc_get_call(call, rxrpc_call_got_kernel); + user_attach_call(call, user_call_ID); + rxrpc_get_call(call, rxrpc_call_got_userid); + rb_link_node(&call->sock_node, parent, pp); + rb_insert_color(&call->sock_node, &rx->calls); + set_bit(RXRPC_CALL_HAS_USERID, &call->flags); } - _leave(" = 0"); + list_add(&call->sock_link, &rx->sock_calls); + + write_unlock(&rx->call_lock); + + write_lock(&rxrpc_call_lock); + list_add_tail(&call->link, &rxrpc_calls); + write_unlock(&rxrpc_call_lock); + + b->call_backlog[call_head] = call; + smp_store_release(&b->call_backlog_head, (call_head + 1) & (size - 1)); + _leave(" = 0 [%d -> %lx]", call->debug_id, user_call_ID); return 0; + +id_in_use: + write_unlock(&rx->call_lock); + rxrpc_cleanup_call(call); + _leave(" = -EBADSLT"); + return -EBADSLT; } /* - * accept an incoming call that needs peer, transport and/or connection setting - * up + * Preallocate sufficient service connections, calls and peers to cover the + * entire backlog of a socket. When a new call comes in, if we don't have + * sufficient of each available, the call gets rejected as busy or ignored. + * + * The backlog is replenished when a connection is accepted or rejected. */ -static int rxrpc_accept_incoming_call(struct rxrpc_local *local, - struct rxrpc_sock *rx, - struct sk_buff *skb, - struct sockaddr_rxrpc *srx) +int rxrpc_service_prealloc(struct rxrpc_sock *rx, gfp_t gfp) { - struct rxrpc_connection *conn; - struct rxrpc_skb_priv *sp, *nsp; - struct rxrpc_call *call; - struct sk_buff *notification; - int ret; + struct rxrpc_backlog *b = rx->backlog; - _enter(""); + if (!b) { + b = kzalloc(sizeof(struct rxrpc_backlog), gfp); + if (!b) + return -ENOMEM; + rx->backlog = b; + } + + if (rx->discard_new_call) + return 0; + + while (rxrpc_service_prealloc_one(rx, b, NULL, NULL, 0, gfp) == 0) + ; - sp = rxrpc_skb(skb); + return 0; +} - /* get a notification message to send to the server app */ - notification = alloc_skb(0, GFP_NOFS); - if (!notification) { - _debug("no memory"); - ret = -ENOMEM; - goto error_nofree; +/* + * Discard the preallocation on a service. + */ +void rxrpc_discard_prealloc(struct rxrpc_sock *rx) +{ + struct rxrpc_backlog *b = rx->backlog; + unsigned int size = RXRPC_BACKLOG_MAX, head, tail; + + if (!b) + return; + rx->backlog = NULL; + + /* Make sure that there aren't any incoming calls in progress before we + * clear the preallocation buffers. + */ + spin_lock_bh(&rx->incoming_lock); + spin_unlock_bh(&rx->incoming_lock); + + head = b->peer_backlog_head; + tail = b->peer_backlog_tail; + while (CIRC_CNT(head, tail, size) > 0) { + struct rxrpc_peer *peer = b->peer_backlog[tail]; + kfree(peer); + tail = (tail + 1) & (size - 1); } - rxrpc_new_skb(notification); - notification->mark = RXRPC_SKB_MARK_NEW_CALL; - - conn = rxrpc_incoming_connection(local, srx, skb); - if (IS_ERR(conn)) { - _debug("no conn"); - ret = PTR_ERR(conn); - goto error; + + head = b->conn_backlog_head; + tail = b->conn_backlog_tail; + while (CIRC_CNT(head, tail, size) > 0) { + struct rxrpc_connection *conn = b->conn_backlog[tail]; + write_lock(&rxrpc_connection_lock); + list_del(&conn->link); + list_del(&conn->proc_link); + write_unlock(&rxrpc_connection_lock); + kfree(conn); + tail = (tail + 1) & (size - 1); } - call = rxrpc_incoming_call(rx, conn, skb); - rxrpc_put_connection(conn); - if (IS_ERR(call)) { - _debug("no call"); - ret = PTR_ERR(call); - goto error; + head = b->call_backlog_head; + tail = b->call_backlog_tail; + while (CIRC_CNT(head, tail, size) > 0) { + struct rxrpc_call *call = b->call_backlog[tail]; + if (rx->discard_new_call) { + _debug("discard %lx", call->user_call_ID); + rx->discard_new_call(call, call->user_call_ID); + rxrpc_put_call(call, rxrpc_call_put_kernel); + } + rxrpc_call_completed(call); + rxrpc_release_call(rx, call); + rxrpc_put_call(call, rxrpc_call_put); + tail = (tail + 1) & (size - 1); } - /* attach the call to the socket */ - read_lock_bh(&local->services_lock); - if (rx->sk.sk_state == RXRPC_CLOSE) - goto invalid_service; + kfree(b); +} - write_lock(&rx->call_lock); - if (!test_and_set_bit(RXRPC_CALL_INIT_ACCEPT, &call->flags)) { - rxrpc_get_call(call); - - spin_lock(&call->conn->state_lock); - if (sp->hdr.securityIndex > 0 && - call->conn->state == RXRPC_CONN_SERVICE_UNSECURED) { - _debug("await conn sec"); - list_add_tail(&call->accept_link, &rx->secureq); - call->conn->state = RXRPC_CONN_SERVICE_CHALLENGING; - set_bit(RXRPC_CONN_EV_CHALLENGE, &call->conn->events); - rxrpc_queue_conn(call->conn); - } else { - _debug("conn ready"); - call->state = RXRPC_CALL_SERVER_ACCEPTING; - list_add_tail(&call->accept_link, &rx->acceptq); - rxrpc_get_call(call); - atomic_inc(&call->skb_count); - nsp = rxrpc_skb(notification); - nsp->call = call; - - ASSERTCMP(atomic_read(&call->usage), >=, 3); - - _debug("notify"); - spin_lock(&call->lock); - ret = rxrpc_queue_rcv_skb(call, notification, true, - false); - spin_unlock(&call->lock); - notification = NULL; - BUG_ON(ret < 0); +/* + * Allocate a new incoming call from the prealloc pool, along with a connection + * and a peer as necessary. + */ +static struct rxrpc_call *rxrpc_alloc_incoming_call(struct rxrpc_sock *rx, + struct rxrpc_local *local, + struct rxrpc_connection *conn, + struct sk_buff *skb) +{ + struct rxrpc_backlog *b = rx->backlog; + struct rxrpc_peer *peer, *xpeer; + struct rxrpc_call *call; + unsigned short call_head, conn_head, peer_head; + unsigned short call_tail, conn_tail, peer_tail; + unsigned short call_count, conn_count; + + /* #calls >= #conns >= #peers must hold true. */ + call_head = smp_load_acquire(&b->call_backlog_head); + call_tail = b->call_backlog_tail; + call_count = CIRC_CNT(call_head, call_tail, RXRPC_BACKLOG_MAX); + conn_head = smp_load_acquire(&b->conn_backlog_head); + conn_tail = b->conn_backlog_tail; + conn_count = CIRC_CNT(conn_head, conn_tail, RXRPC_BACKLOG_MAX); + ASSERTCMP(conn_count, >=, call_count); + peer_head = smp_load_acquire(&b->peer_backlog_head); + peer_tail = b->peer_backlog_tail; + ASSERTCMP(CIRC_CNT(peer_head, peer_tail, RXRPC_BACKLOG_MAX), >=, + conn_count); + + if (call_count == 0) + return NULL; + + if (!conn) { + /* No connection. We're going to need a peer to start off + * with. If one doesn't yet exist, use a spare from the + * preallocation set. We dump the address into the spare in + * anticipation - and to save on stack space. + */ + xpeer = b->peer_backlog[peer_tail]; + if (rxrpc_extract_addr_from_skb(&xpeer->srx, skb) < 0) + return NULL; + + peer = rxrpc_lookup_incoming_peer(local, xpeer); + if (peer == xpeer) { + b->peer_backlog[peer_tail] = NULL; + smp_store_release(&b->peer_backlog_tail, + (peer_tail + 1) & + (RXRPC_BACKLOG_MAX - 1)); } - spin_unlock(&call->conn->state_lock); - _debug("queued"); + /* Now allocate and set up the connection */ + conn = b->conn_backlog[conn_tail]; + b->conn_backlog[conn_tail] = NULL; + smp_store_release(&b->conn_backlog_tail, + (conn_tail + 1) & (RXRPC_BACKLOG_MAX - 1)); + rxrpc_get_local(local); + conn->params.local = local; + conn->params.peer = peer; + rxrpc_see_connection(conn); + rxrpc_new_incoming_connection(conn, skb); + } else { + rxrpc_get_connection(conn); } - write_unlock(&rx->call_lock); - _debug("process"); - rxrpc_fast_process_packet(call, skb); + /* And now we can allocate and set up a new call */ + call = b->call_backlog[call_tail]; + b->call_backlog[call_tail] = NULL; + smp_store_release(&b->call_backlog_tail, + (call_tail + 1) & (RXRPC_BACKLOG_MAX - 1)); - _debug("done"); - read_unlock_bh(&local->services_lock); - rxrpc_free_skb(notification); - rxrpc_put_call(call); - _leave(" = 0"); - return 0; - -invalid_service: - _debug("invalid"); - read_unlock_bh(&local->services_lock); - - read_lock_bh(&call->state_lock); - if (!test_bit(RXRPC_CALL_RELEASED, &call->flags) && - !test_and_set_bit(RXRPC_CALL_EV_RELEASE, &call->events)) { - rxrpc_get_call(call); - rxrpc_queue_call(call); - } - read_unlock_bh(&call->state_lock); - rxrpc_put_call(call); - ret = -ECONNREFUSED; -error: - rxrpc_free_skb(notification); -error_nofree: - _leave(" = %d", ret); - return ret; + rxrpc_see_call(call); + call->conn = conn; + call->peer = rxrpc_get_peer(conn->params.peer); + return call; } /* - * 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 + * Set up a new incoming call. Called in BH context with the RCU read lock + * held. + * + * If this is for a kernel service, when we allocate the call, it will have + * three refs on it: (1) the kernel service, (2) the user_call_ID tree, (3) the + * retainer ref obtained from the backlog buffer. Prealloc calls for userspace + * services only have the ref from the backlog buffer. We want to pass this + * ref to non-BH context to dispose of. + * + * If we want to report an error, we mark the skb with the packet type and + * abort code and return NULL. */ -void rxrpc_accept_incoming_calls(struct rxrpc_local *local) +struct rxrpc_call *rxrpc_new_incoming_call(struct rxrpc_local *local, + struct rxrpc_connection *conn, + struct sk_buff *skb) { - struct rxrpc_skb_priv *sp; - struct sockaddr_rxrpc srx; + struct rxrpc_skb_priv *sp = rxrpc_skb(skb); struct rxrpc_sock *rx; - struct rxrpc_wire_header whdr; - struct sk_buff *skb; - int ret; + struct rxrpc_call *call; + u16 service_id = sp->hdr.serviceId; - _enter("%d", local->debug_id); + _enter(""); - skb = skb_dequeue(&local->accept_queue); - if (!skb) { - _leave("\n"); - return; + /* Get the socket providing the service */ + rx = rcu_dereference(local->service); + if (rx && service_id == rx->srx.srx_service) + goto found_service; + + trace_rxrpc_abort("INV", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq, + RX_INVALID_OPERATION, EOPNOTSUPP); + skb->mark = RXRPC_SKB_MARK_LOCAL_ABORT; + skb->priority = RX_INVALID_OPERATION; + _leave(" = NULL [service]"); + return NULL; + +found_service: + spin_lock(&rx->incoming_lock); + if (rx->sk.sk_state == RXRPC_CLOSE) { + trace_rxrpc_abort("CLS", sp->hdr.cid, sp->hdr.callNumber, + sp->hdr.seq, RX_INVALID_OPERATION, ESHUTDOWN); + skb->mark = RXRPC_SKB_MARK_LOCAL_ABORT; + skb->priority = RX_INVALID_OPERATION; + _leave(" = NULL [close]"); + call = NULL; + goto out; } - _net("incoming call skb %p", skb); - - sp = rxrpc_skb(skb); - - /* Set up a response packet header in case we need it */ - whdr.epoch = htonl(sp->hdr.epoch); - whdr.cid = htonl(sp->hdr.cid); - whdr.callNumber = htonl(sp->hdr.callNumber); - whdr.seq = htonl(sp->hdr.seq); - whdr.serial = 0; - whdr.flags = 0; - whdr.type = 0; - whdr.userStatus = 0; - whdr.securityIndex = sp->hdr.securityIndex; - whdr._rsvd = 0; - whdr.serviceId = htons(sp->hdr.serviceId); - - if (rxrpc_extract_addr_from_skb(&srx, skb) < 0) - goto drop; - - /* get the socket providing the service */ - read_lock_bh(&local->services_lock); - list_for_each_entry(rx, &local->services, listen_link) { - if (rx->srx.srx_service == sp->hdr.serviceId && - rx->sk.sk_state != RXRPC_CLOSE) - goto found_service; + call = rxrpc_alloc_incoming_call(rx, local, conn, skb); + if (!call) { + skb->mark = RXRPC_SKB_MARK_BUSY; + _leave(" = NULL [busy]"); + call = NULL; + goto out; } - read_unlock_bh(&local->services_lock); - goto invalid_service; -found_service: - _debug("found service %hd", rx->srx.srx_service); - if (sk_acceptq_is_full(&rx->sk)) - goto backlog_full; - sk_acceptq_added(&rx->sk); - sock_hold(&rx->sk); - read_unlock_bh(&local->services_lock); - - ret = rxrpc_accept_incoming_call(local, rx, skb, &srx); - if (ret < 0) - sk_acceptq_removed(&rx->sk); - sock_put(&rx->sk); - switch (ret) { - case -ECONNRESET: /* old calls are ignored */ - case -ECONNABORTED: /* aborted calls are reaborted or ignored */ - case 0: - return; - case -ECONNREFUSED: - goto invalid_service; - case -EBUSY: - goto busy; - case -EKEYREJECTED: - goto security_mismatch; + trace_rxrpc_receive(call, rxrpc_receive_incoming, + sp->hdr.serial, sp->hdr.seq); + + /* Make the call live. */ + rxrpc_incoming_call(rx, call, skb); + conn = call->conn; + + if (rx->notify_new_call) + rx->notify_new_call(&rx->sk, call, call->user_call_ID); + else + sk_acceptq_added(&rx->sk); + + spin_lock(&conn->state_lock); + switch (conn->state) { + case RXRPC_CONN_SERVICE_UNSECURED: + conn->state = RXRPC_CONN_SERVICE_CHALLENGING; + set_bit(RXRPC_CONN_EV_CHALLENGE, &call->conn->events); + rxrpc_queue_conn(call->conn); + break; + + case RXRPC_CONN_SERVICE: + write_lock(&call->state_lock); + if (rx->discard_new_call) + call->state = RXRPC_CALL_SERVER_RECV_REQUEST; + else + call->state = RXRPC_CALL_SERVER_ACCEPTING; + write_unlock(&call->state_lock); + break; + + case RXRPC_CONN_REMOTELY_ABORTED: + rxrpc_set_call_completion(call, RXRPC_CALL_REMOTELY_ABORTED, + conn->remote_abort, ECONNABORTED); + break; + case RXRPC_CONN_LOCALLY_ABORTED: + rxrpc_abort_call("CON", call, sp->hdr.seq, + conn->local_abort, ECONNABORTED); + break; default: BUG(); } + spin_unlock(&conn->state_lock); -backlog_full: - read_unlock_bh(&local->services_lock); -busy: - rxrpc_busy(local, &srx, &whdr); - rxrpc_free_skb(skb); - return; + if (call->state == RXRPC_CALL_SERVER_ACCEPTING) + rxrpc_notify_socket(call); -drop: - rxrpc_free_skb(skb); - return; + /* We have to discard the prealloc queue's ref here and rely on a + * combination of the RCU read lock and refs held either by the socket + * (recvmsg queue, to-be-accepted queue or user ID tree) or the kernel + * service to prevent the call from being deallocated too early. + */ + rxrpc_put_call(call, rxrpc_call_put); -invalid_service: - skb->priority = RX_INVALID_OPERATION; - rxrpc_reject_packet(local, skb); - return; - - /* can't change connection security type mid-flow */ -security_mismatch: - skb->priority = RX_PROTOCOL_ERROR; - rxrpc_reject_packet(local, skb); - return; + _leave(" = %p{%d}", call, call->debug_id); +out: + spin_unlock(&rx->incoming_lock); + return call; } /* @@ -286,7 +430,8 @@ security_mismatch: * - assign the user call ID to the call at the front of the queue */ struct rxrpc_call *rxrpc_accept_call(struct rxrpc_sock *rx, - unsigned long user_call_ID) + unsigned long user_call_ID, + rxrpc_notify_rx_t notify_rx) { struct rxrpc_call *call; struct rb_node *parent, **pp; @@ -298,12 +443,13 @@ struct rxrpc_call *rxrpc_accept_call(struct rxrpc_sock *rx, write_lock(&rx->call_lock); - ret = -ENODATA; - if (list_empty(&rx->acceptq)) - goto out; + if (list_empty(&rx->to_be_accepted)) { + write_unlock(&rx->call_lock); + kleave(" = -ENODATA [empty]"); + return ERR_PTR(-ENODATA); + } /* check the user ID isn't already in use */ - ret = -EBADSLT; pp = &rx->calls.rb_node; parent = NULL; while (*pp) { @@ -315,62 +461,59 @@ struct rxrpc_call *rxrpc_accept_call(struct rxrpc_sock *rx, else if (user_call_ID > call->user_call_ID) pp = &(*pp)->rb_right; else - goto out; + goto id_in_use; } - /* dequeue the first call and check it's still valid */ - call = list_entry(rx->acceptq.next, struct rxrpc_call, accept_link); + /* Dequeue the first call and check it's still valid. We gain + * responsibility for the queue's reference. + */ + call = list_entry(rx->to_be_accepted.next, + struct rxrpc_call, accept_link); list_del_init(&call->accept_link); sk_acceptq_removed(&rx->sk); + rxrpc_see_call(call); write_lock_bh(&call->state_lock); switch (call->state) { case RXRPC_CALL_SERVER_ACCEPTING: call->state = RXRPC_CALL_SERVER_RECV_REQUEST; break; - case RXRPC_CALL_REMOTELY_ABORTED: - case RXRPC_CALL_LOCALLY_ABORTED: - ret = -ECONNABORTED; - goto out_release; - case RXRPC_CALL_NETWORK_ERROR: - ret = call->conn->error; + case RXRPC_CALL_COMPLETE: + ret = call->error; goto out_release; - case RXRPC_CALL_DEAD: - ret = -ETIME; - goto out_discard; default: BUG(); } /* formalise the acceptance */ + call->notify_rx = notify_rx; call->user_call_ID = user_call_ID; + rxrpc_get_call(call, rxrpc_call_got_userid); rb_link_node(&call->sock_node, parent, pp); rb_insert_color(&call->sock_node, &rx->calls); if (test_and_set_bit(RXRPC_CALL_HAS_USERID, &call->flags)) BUG(); - if (test_and_set_bit(RXRPC_CALL_EV_ACCEPTED, &call->events)) - BUG(); - rxrpc_queue_call(call); - rxrpc_get_call(call); write_unlock_bh(&call->state_lock); write_unlock(&rx->call_lock); + rxrpc_notify_socket(call); + rxrpc_service_prealloc(rx, GFP_KERNEL); _leave(" = %p{%d}", call, call->debug_id); return call; - /* if the call is already dying or dead, then we leave the socket's ref - * on it to be released by rxrpc_dead_call_expired() as induced by - * rxrpc_release_call() */ out_release: _debug("release %p", call); - if (!test_bit(RXRPC_CALL_RELEASED, &call->flags) && - !test_and_set_bit(RXRPC_CALL_EV_RELEASE, &call->events)) - rxrpc_queue_call(call); -out_discard: write_unlock_bh(&call->state_lock); - _debug("discard %p", call); -out: write_unlock(&rx->call_lock); + rxrpc_release_call(rx, call); + rxrpc_put_call(call, rxrpc_call_put); + goto out; + +id_in_use: + ret = -EBADSLT; + write_unlock(&rx->call_lock); +out: + rxrpc_service_prealloc(rx, GFP_KERNEL); _leave(" = %d", ret); return ERR_PTR(ret); } @@ -382,6 +525,7 @@ out: int rxrpc_reject_call(struct rxrpc_sock *rx) { struct rxrpc_call *call; + bool abort = false; int ret; _enter(""); @@ -390,88 +534,73 @@ int rxrpc_reject_call(struct rxrpc_sock *rx) write_lock(&rx->call_lock); - ret = -ENODATA; - if (list_empty(&rx->acceptq)) - goto out; + if (list_empty(&rx->to_be_accepted)) { + write_unlock(&rx->call_lock); + return -ENODATA; + } - /* dequeue the first call and check it's still valid */ - call = list_entry(rx->acceptq.next, struct rxrpc_call, accept_link); + /* Dequeue the first call and check it's still valid. We gain + * responsibility for the queue's reference. + */ + call = list_entry(rx->to_be_accepted.next, + struct rxrpc_call, accept_link); list_del_init(&call->accept_link); sk_acceptq_removed(&rx->sk); + rxrpc_see_call(call); write_lock_bh(&call->state_lock); switch (call->state) { case RXRPC_CALL_SERVER_ACCEPTING: - call->state = RXRPC_CALL_SERVER_BUSY; - if (test_and_set_bit(RXRPC_CALL_EV_REJECT_BUSY, &call->events)) - rxrpc_queue_call(call); - ret = 0; - goto out_release; - case RXRPC_CALL_REMOTELY_ABORTED: - case RXRPC_CALL_LOCALLY_ABORTED: - ret = -ECONNABORTED; - goto out_release; - case RXRPC_CALL_NETWORK_ERROR: - ret = call->conn->error; - goto out_release; - case RXRPC_CALL_DEAD: - ret = -ETIME; + __rxrpc_abort_call("REJ", call, 1, RX_USER_ABORT, ECONNABORTED); + abort = true; + /* fall through */ + case RXRPC_CALL_COMPLETE: + ret = call->error; goto out_discard; default: BUG(); } - /* if the call is already dying or dead, then we leave the socket's ref - * on it to be released by rxrpc_dead_call_expired() as induced by - * rxrpc_release_call() */ -out_release: - _debug("release %p", call); - if (!test_bit(RXRPC_CALL_RELEASED, &call->flags) && - !test_and_set_bit(RXRPC_CALL_EV_RELEASE, &call->events)) - rxrpc_queue_call(call); out_discard: write_unlock_bh(&call->state_lock); - _debug("discard %p", call); -out: write_unlock(&rx->call_lock); + if (abort) { + rxrpc_send_abort_packet(call); + rxrpc_release_call(rx, call); + rxrpc_put_call(call, rxrpc_call_put); + } + rxrpc_service_prealloc(rx, GFP_KERNEL); _leave(" = %d", ret); return ret; } -/** - * rxrpc_kernel_accept_call - Allow a kernel service to accept an incoming call - * @sock: The socket on which the impending call is waiting - * @user_call_ID: The tag to attach to the call +/* + * rxrpc_kernel_charge_accept - Charge up socket with preallocated calls + * @sock: The socket on which to preallocate + * @notify_rx: Event notification function for the call + * @user_attach_call: Func to attach call to user_call_ID + * @user_call_ID: The tag to attach to the preallocated call + * @gfp: The allocation conditions. * - * Allow a kernel service to accept an incoming call, assuming the incoming - * call is still valid. - */ -struct rxrpc_call *rxrpc_kernel_accept_call(struct socket *sock, - unsigned long user_call_ID) -{ - struct rxrpc_call *call; - - _enter(",%lx", user_call_ID); - call = rxrpc_accept_call(rxrpc_sk(sock->sk), user_call_ID); - _leave(" = %p", call); - return call; -} -EXPORT_SYMBOL(rxrpc_kernel_accept_call); - -/** - * rxrpc_kernel_reject_call - Allow a kernel service to reject an incoming call - * @sock: The socket on which the impending call is waiting + * Charge up the socket with preallocated calls, each with a user ID. A + * function should be provided to effect the attachment from the user's side. + * The user is given a ref to hold on the call. * - * Allow a kernel service to reject an incoming call with a BUSY message, - * assuming the incoming call is still valid. + * Note that the call may be come connected before this function returns. */ -int rxrpc_kernel_reject_call(struct socket *sock) +int rxrpc_kernel_charge_accept(struct socket *sock, + rxrpc_notify_rx_t notify_rx, + rxrpc_user_attach_call_t user_attach_call, + unsigned long user_call_ID, gfp_t gfp) { - int ret; + struct rxrpc_sock *rx = rxrpc_sk(sock->sk); + struct rxrpc_backlog *b = rx->backlog; - _enter(""); - ret = rxrpc_reject_call(rxrpc_sk(sock->sk)); - _leave(" = %d", ret); - return ret; + if (sock->sk->sk_state == RXRPC_CLOSE) + return -ESHUTDOWN; + + return rxrpc_service_prealloc_one(rx, b, notify_rx, + user_attach_call, user_call_ID, + gfp); } -EXPORT_SYMBOL(rxrpc_kernel_reject_call); +EXPORT_SYMBOL(rxrpc_kernel_charge_accept);