/*
* set up an incoming call
* - called in process context with IRQs enabled
*/
struct rxrpc_call *rxrpc_incoming_call(struct rxrpc_sock *rx,
struct rxrpc_connection *conn,
struct rxrpc_header *hdr,
gfp_t gfp)
{
struct rxrpc_call *call, *candidate;
struct rb_node **p, *parent;
__be32 call_id;
_enter(",%d,,%x", conn->debug_id, gfp);
ASSERT(rx != NULL);
candidate = rxrpc_alloc_call(gfp);
if (!candidate)
return ERR_PTR(-EBUSY);
candidate->socket = rx;
candidate->conn = conn;
candidate->cid = hdr->cid;
candidate->call_id = hdr->callNumber;
candidate->channel = ntohl(hdr->cid) & RXRPC_CHANNELMASK;
candidate->rx_data_post = 0;
candidate->state = RXRPC_CALL_SERVER_ACCEPTING;
if (conn->security_ix > 0)
candidate->state = RXRPC_CALL_SERVER_SECURING;
write_lock_bh(&conn->lock);
/* set the channel for this call */
call = conn->channels[candidate->channel];
_debug("channel[%u] is %p", candidate->channel, call);
if (call && call->call_id == hdr->callNumber) {
/* already set; must've been a duplicate packet */
_debug("extant call [%d]", call->state);
ASSERTCMP(call->conn, ==, conn);
read_lock(&call->state_lock);
switch (call->state) {
case RXRPC_CALL_LOCALLY_ABORTED:
if (!test_and_set_bit(RXRPC_CALL_ABORT, &call->events))
rxrpc_queue_call(call);
case RXRPC_CALL_REMOTELY_ABORTED:
read_unlock(&call->state_lock);
goto aborted_call;
default:
rxrpc_get_call(call);
read_unlock(&call->state_lock);
goto extant_call;
}
}
/*
* Allocate a new client call.
*/
static struct rxrpc_call *rxrpc_alloc_client_call(struct sockaddr_rxrpc *srx,
gfp_t gfp)
{
struct rxrpc_call *call;
ktime_t now;
_enter("");
call = rxrpc_alloc_call(gfp);
if (!call)
return ERR_PTR(-ENOMEM);
call->state = RXRPC_CALL_CLIENT_AWAIT_CONN;
call->service_id = srx->srx_service;
call->tx_phase = true;
now = ktime_get_real();
call->acks_latest_ts = now;
call->cong_tstamp = now;
_leave(" = %p", call);
return call;
}
/*
* allocate a new client call and attempt to get a connection slot for it
*/
static struct rxrpc_call *rxrpc_alloc_client_call(
struct rxrpc_sock *rx,
struct rxrpc_transport *trans,
struct rxrpc_conn_bundle *bundle,
gfp_t gfp)
{
struct rxrpc_call *call;
int ret;
_enter("");
ASSERT(rx != NULL);
ASSERT(trans != NULL);
ASSERT(bundle != NULL);
call = rxrpc_alloc_call(gfp);
if (!call)
return ERR_PTR(-ENOMEM);
sock_hold(&rx->sk);
call->socket = rx;
call->rx_data_post = 1;
ret = rxrpc_connect_call(rx, trans, bundle, call, gfp);
if (ret < 0) {
kmem_cache_free(rxrpc_call_jar, call);
return ERR_PTR(ret);
}
spin_lock(&call->conn->trans->peer->lock);
list_add(&call->error_link, &call->conn->trans->peer->error_targets);
spin_unlock(&call->conn->trans->peer->lock);
call->lifetimer.expires = jiffies + rxrpc_call_max_lifetime * HZ;
add_timer(&call->lifetimer);
_leave(" = %p", call);
return call;
}
/*
* 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_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)
{
const void *here = __builtin_return_address(0);
struct rxrpc_call *call;
struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
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));
}
head = b->conn_backlog_head;
tail = READ_ONCE(b->conn_backlog_tail);
if (CIRC_CNT(head, tail, size) < max) {
struct rxrpc_connection *conn;
conn = rxrpc_prealloc_service_connection(rxnet, gfp);
if (!conn)
return -ENOMEM;
b->conn_backlog[head] = conn;
smp_store_release(&b->conn_backlog_head,
(head + 1) & (size - 1));
trace_rxrpc_conn(conn, rxrpc_conn_new_service,
atomic_read(&conn->usage), here);
}
/* 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;
trace_rxrpc_call(call, rxrpc_call_new_service,
atomic_read(&call->usage),
here, (const void *)user_call_ID);
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;
}
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);
}
list_add(&call->sock_link, &rx->sock_calls);
write_unlock(&rx->call_lock);
write_lock(&rxnet->call_lock);
list_add_tail(&call->link, &rxnet->calls);
write_unlock(&rxnet->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;
}
