| 1 | /* |
| 2 | * Copyright (C) 2013 Julien Desfossez <jdesfossez@efficios.com> |
| 3 | * Copyright (C) 2013 David Goulet <dgoulet@efficios.com> |
| 4 | * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 5 | * |
| 6 | * SPDX-License-Identifier: GPL-2.0-only |
| 7 | * |
| 8 | */ |
| 9 | |
| 10 | #define _LGPL_SOURCE |
| 11 | #include <common/common.h> |
| 12 | #include <urcu/rculist.h> |
| 13 | |
| 14 | #include "connection.h" |
| 15 | #include "stream.h" |
| 16 | #include "viewer-session.h" |
| 17 | |
| 18 | bool connection_get(struct relay_connection *conn) |
| 19 | { |
| 20 | return urcu_ref_get_unless_zero(&conn->ref); |
| 21 | } |
| 22 | |
| 23 | struct relay_connection *connection_get_by_sock(struct lttng_ht *relay_connections_ht, |
| 24 | int sock) |
| 25 | { |
| 26 | struct lttng_ht_node_ulong *node; |
| 27 | struct lttng_ht_iter iter; |
| 28 | struct relay_connection *conn = NULL; |
| 29 | |
| 30 | assert(sock >= 0); |
| 31 | |
| 32 | rcu_read_lock(); |
| 33 | lttng_ht_lookup(relay_connections_ht, (void *)((unsigned long) sock), |
| 34 | &iter); |
| 35 | node = lttng_ht_iter_get_node_ulong(&iter); |
| 36 | if (!node) { |
| 37 | DBG2("Relay connection by sock %d not found", sock); |
| 38 | goto end; |
| 39 | } |
| 40 | conn = caa_container_of(node, struct relay_connection, sock_n); |
| 41 | if (!connection_get(conn)) { |
| 42 | conn = NULL; |
| 43 | } |
| 44 | end: |
| 45 | rcu_read_unlock(); |
| 46 | return conn; |
| 47 | } |
| 48 | |
| 49 | int connection_reset_protocol_state(struct relay_connection *connection) |
| 50 | { |
| 51 | int ret = 0; |
| 52 | |
| 53 | switch (connection->type) { |
| 54 | case RELAY_DATA: |
| 55 | connection->protocol.data.state_id = |
| 56 | DATA_CONNECTION_STATE_RECEIVE_HEADER; |
| 57 | memset(&connection->protocol.data.state.receive_header, |
| 58 | 0, |
| 59 | sizeof(connection->protocol.data.state.receive_header)); |
| 60 | connection->protocol.data.state.receive_header.left_to_receive = |
| 61 | sizeof(struct lttcomm_relayd_data_hdr); |
| 62 | break; |
| 63 | case RELAY_CONTROL: |
| 64 | connection->protocol.ctrl.state_id = |
| 65 | CTRL_CONNECTION_STATE_RECEIVE_HEADER; |
| 66 | memset(&connection->protocol.ctrl.state.receive_header, |
| 67 | 0, |
| 68 | sizeof(connection->protocol.ctrl.state.receive_header)); |
| 69 | connection->protocol.data.state.receive_header.left_to_receive = |
| 70 | sizeof(struct lttcomm_relayd_hdr); |
| 71 | ret = lttng_dynamic_buffer_set_size( |
| 72 | &connection->protocol.ctrl.reception_buffer, |
| 73 | sizeof(struct lttcomm_relayd_hdr)); |
| 74 | if (ret) { |
| 75 | ERR("Failed to reinitialize control connection reception buffer size to %zu bytes.", sizeof(struct lttcomm_relayd_hdr)); |
| 76 | goto end; |
| 77 | } |
| 78 | break; |
| 79 | default: |
| 80 | goto end; |
| 81 | } |
| 82 | DBG("Reset communication state of relay connection (fd = %i)", |
| 83 | connection->sock->fd); |
| 84 | end: |
| 85 | return ret; |
| 86 | } |
| 87 | |
| 88 | struct relay_connection *connection_create(struct lttcomm_sock *sock, |
| 89 | enum connection_type type) |
| 90 | { |
| 91 | struct relay_connection *conn; |
| 92 | |
| 93 | conn = zmalloc(sizeof(*conn)); |
| 94 | if (!conn) { |
| 95 | PERROR("zmalloc relay connection"); |
| 96 | goto end; |
| 97 | } |
| 98 | urcu_ref_init(&conn->ref); |
| 99 | conn->type = type; |
| 100 | conn->sock = sock; |
| 101 | lttng_ht_node_init_ulong(&conn->sock_n, (unsigned long) conn->sock->fd); |
| 102 | if (conn->type == RELAY_CONTROL) { |
| 103 | lttng_dynamic_buffer_init(&conn->protocol.ctrl.reception_buffer); |
| 104 | } |
| 105 | connection_reset_protocol_state(conn); |
| 106 | end: |
| 107 | return conn; |
| 108 | } |
| 109 | |
| 110 | static void rcu_free_connection(struct rcu_head *head) |
| 111 | { |
| 112 | struct relay_connection *conn = |
| 113 | caa_container_of(head, struct relay_connection, rcu_node); |
| 114 | |
| 115 | lttcomm_destroy_sock(conn->sock); |
| 116 | if (conn->viewer_session) { |
| 117 | viewer_session_destroy(conn->viewer_session); |
| 118 | conn->viewer_session = NULL; |
| 119 | } |
| 120 | if (conn->type == RELAY_CONTROL) { |
| 121 | lttng_dynamic_buffer_reset( |
| 122 | &conn->protocol.ctrl.reception_buffer); |
| 123 | } |
| 124 | free(conn); |
| 125 | } |
| 126 | |
| 127 | static void destroy_connection(struct relay_connection *conn) |
| 128 | { |
| 129 | call_rcu(&conn->rcu_node, rcu_free_connection); |
| 130 | } |
| 131 | |
| 132 | static void connection_release(struct urcu_ref *ref) |
| 133 | { |
| 134 | struct relay_connection *conn = |
| 135 | caa_container_of(ref, struct relay_connection, ref); |
| 136 | |
| 137 | if (conn->in_socket_ht) { |
| 138 | struct lttng_ht_iter iter; |
| 139 | int ret; |
| 140 | |
| 141 | iter.iter.node = &conn->sock_n.node; |
| 142 | ret = lttng_ht_del(conn->socket_ht, &iter); |
| 143 | assert(!ret); |
| 144 | } |
| 145 | |
| 146 | if (conn->session) { |
| 147 | if (session_close(conn->session)) { |
| 148 | ERR("session_close"); |
| 149 | } |
| 150 | conn->session = NULL; |
| 151 | } |
| 152 | if (conn->viewer_session) { |
| 153 | viewer_session_close(conn->viewer_session); |
| 154 | } |
| 155 | destroy_connection(conn); |
| 156 | } |
| 157 | |
| 158 | void connection_put(struct relay_connection *conn) |
| 159 | { |
| 160 | rcu_read_lock(); |
| 161 | urcu_ref_put(&conn->ref, connection_release); |
| 162 | rcu_read_unlock(); |
| 163 | } |
| 164 | |
| 165 | void connection_ht_add(struct lttng_ht *relay_connections_ht, |
| 166 | struct relay_connection *conn) |
| 167 | { |
| 168 | assert(!conn->in_socket_ht); |
| 169 | lttng_ht_add_unique_ulong(relay_connections_ht, &conn->sock_n); |
| 170 | conn->in_socket_ht = 1; |
| 171 | conn->socket_ht = relay_connections_ht; |
| 172 | } |
| 173 | |
| 174 | int connection_set_session(struct relay_connection *conn, |
| 175 | struct relay_session *session) |
| 176 | { |
| 177 | int ret = 0; |
| 178 | |
| 179 | assert(conn); |
| 180 | assert(session); |
| 181 | assert(!conn->session); |
| 182 | |
| 183 | if (connection_get(conn)) { |
| 184 | if (session_get(session)) { |
| 185 | conn->session = session; |
| 186 | } else { |
| 187 | ERR("Failed to get session reference in connection_set_session()"); |
| 188 | ret = -1; |
| 189 | } |
| 190 | connection_put(conn); |
| 191 | } else { |
| 192 | ERR("Failed to get connection reference in connection_set_session()"); |
| 193 | ret = -1; |
| 194 | } |
| 195 | return ret; |
| 196 | } |