David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1 | /* RxRPC virtual connection handler |
| 2 | * |
| 3 | * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. |
| 4 | * Written by David Howells (dhowells@redhat.com) |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/module.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 13 | #include <linux/slab.h> |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 14 | #include <linux/net.h> |
| 15 | #include <linux/skbuff.h> |
| 16 | #include <linux/crypto.h> |
| 17 | #include <net/sock.h> |
| 18 | #include <net/af_rxrpc.h> |
| 19 | #include "ar-internal.h" |
| 20 | |
David Howells | 5873c08 | 2014-02-07 18:58:44 +0000 | [diff] [blame] | 21 | /* |
| 22 | * Time till a connection expires after last use (in seconds). |
| 23 | */ |
| 24 | unsigned rxrpc_connection_expiry = 10 * 60; |
| 25 | |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 26 | static void rxrpc_connection_reaper(struct work_struct *work); |
| 27 | |
| 28 | LIST_HEAD(rxrpc_connections); |
| 29 | DEFINE_RWLOCK(rxrpc_connection_lock); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 30 | static DECLARE_DELAYED_WORK(rxrpc_connection_reap, rxrpc_connection_reaper); |
| 31 | |
| 32 | /* |
| 33 | * allocate a new client connection bundle |
| 34 | */ |
| 35 | static struct rxrpc_conn_bundle *rxrpc_alloc_bundle(gfp_t gfp) |
| 36 | { |
| 37 | struct rxrpc_conn_bundle *bundle; |
| 38 | |
| 39 | _enter(""); |
| 40 | |
| 41 | bundle = kzalloc(sizeof(struct rxrpc_conn_bundle), gfp); |
| 42 | if (bundle) { |
| 43 | INIT_LIST_HEAD(&bundle->unused_conns); |
| 44 | INIT_LIST_HEAD(&bundle->avail_conns); |
| 45 | INIT_LIST_HEAD(&bundle->busy_conns); |
| 46 | init_waitqueue_head(&bundle->chanwait); |
| 47 | atomic_set(&bundle->usage, 1); |
| 48 | } |
| 49 | |
| 50 | _leave(" = %p", bundle); |
| 51 | return bundle; |
| 52 | } |
| 53 | |
| 54 | /* |
| 55 | * compare bundle parameters with what we're looking for |
| 56 | * - return -ve, 0 or +ve |
| 57 | */ |
| 58 | static inline |
| 59 | int rxrpc_cmp_bundle(const struct rxrpc_conn_bundle *bundle, |
| 60 | struct key *key, __be16 service_id) |
| 61 | { |
| 62 | return (bundle->service_id - service_id) ?: |
| 63 | ((unsigned long) bundle->key - (unsigned long) key); |
| 64 | } |
| 65 | |
| 66 | /* |
| 67 | * get bundle of client connections that a client socket can make use of |
| 68 | */ |
| 69 | struct rxrpc_conn_bundle *rxrpc_get_bundle(struct rxrpc_sock *rx, |
| 70 | struct rxrpc_transport *trans, |
| 71 | struct key *key, |
| 72 | __be16 service_id, |
| 73 | gfp_t gfp) |
| 74 | { |
| 75 | struct rxrpc_conn_bundle *bundle, *candidate; |
| 76 | struct rb_node *p, *parent, **pp; |
| 77 | |
| 78 | _enter("%p{%x},%x,%hx,", |
Al Viro | 582ee43 | 2007-07-26 17:33:39 +0100 | [diff] [blame] | 79 | rx, key_serial(key), trans->debug_id, ntohs(service_id)); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 80 | |
| 81 | if (rx->trans == trans && rx->bundle) { |
| 82 | atomic_inc(&rx->bundle->usage); |
| 83 | return rx->bundle; |
| 84 | } |
| 85 | |
| 86 | /* search the extant bundles first for one that matches the specified |
| 87 | * user ID */ |
| 88 | spin_lock(&trans->client_lock); |
| 89 | |
| 90 | p = trans->bundles.rb_node; |
| 91 | while (p) { |
| 92 | bundle = rb_entry(p, struct rxrpc_conn_bundle, node); |
| 93 | |
| 94 | if (rxrpc_cmp_bundle(bundle, key, service_id) < 0) |
| 95 | p = p->rb_left; |
| 96 | else if (rxrpc_cmp_bundle(bundle, key, service_id) > 0) |
| 97 | p = p->rb_right; |
| 98 | else |
| 99 | goto found_extant_bundle; |
| 100 | } |
| 101 | |
| 102 | spin_unlock(&trans->client_lock); |
| 103 | |
| 104 | /* not yet present - create a candidate for a new record and then |
| 105 | * redo the search */ |
| 106 | candidate = rxrpc_alloc_bundle(gfp); |
| 107 | if (!candidate) { |
| 108 | _leave(" = -ENOMEM"); |
| 109 | return ERR_PTR(-ENOMEM); |
| 110 | } |
| 111 | |
| 112 | candidate->key = key_get(key); |
| 113 | candidate->service_id = service_id; |
| 114 | |
| 115 | spin_lock(&trans->client_lock); |
| 116 | |
| 117 | pp = &trans->bundles.rb_node; |
| 118 | parent = NULL; |
| 119 | while (*pp) { |
| 120 | parent = *pp; |
| 121 | bundle = rb_entry(parent, struct rxrpc_conn_bundle, node); |
| 122 | |
| 123 | if (rxrpc_cmp_bundle(bundle, key, service_id) < 0) |
| 124 | pp = &(*pp)->rb_left; |
| 125 | else if (rxrpc_cmp_bundle(bundle, key, service_id) > 0) |
| 126 | pp = &(*pp)->rb_right; |
| 127 | else |
| 128 | goto found_extant_second; |
| 129 | } |
| 130 | |
| 131 | /* second search also failed; add the new bundle */ |
| 132 | bundle = candidate; |
| 133 | candidate = NULL; |
| 134 | |
| 135 | rb_link_node(&bundle->node, parent, pp); |
| 136 | rb_insert_color(&bundle->node, &trans->bundles); |
| 137 | spin_unlock(&trans->client_lock); |
| 138 | _net("BUNDLE new on trans %d", trans->debug_id); |
| 139 | if (!rx->bundle && rx->sk.sk_state == RXRPC_CLIENT_CONNECTED) { |
| 140 | atomic_inc(&bundle->usage); |
| 141 | rx->bundle = bundle; |
| 142 | } |
| 143 | _leave(" = %p [new]", bundle); |
| 144 | return bundle; |
| 145 | |
| 146 | /* we found the bundle in the list immediately */ |
| 147 | found_extant_bundle: |
| 148 | atomic_inc(&bundle->usage); |
| 149 | spin_unlock(&trans->client_lock); |
| 150 | _net("BUNDLE old on trans %d", trans->debug_id); |
| 151 | if (!rx->bundle && rx->sk.sk_state == RXRPC_CLIENT_CONNECTED) { |
| 152 | atomic_inc(&bundle->usage); |
| 153 | rx->bundle = bundle; |
| 154 | } |
| 155 | _leave(" = %p [extant %d]", bundle, atomic_read(&bundle->usage)); |
| 156 | return bundle; |
| 157 | |
| 158 | /* we found the bundle on the second time through the list */ |
| 159 | found_extant_second: |
| 160 | atomic_inc(&bundle->usage); |
| 161 | spin_unlock(&trans->client_lock); |
| 162 | kfree(candidate); |
| 163 | _net("BUNDLE old2 on trans %d", trans->debug_id); |
| 164 | if (!rx->bundle && rx->sk.sk_state == RXRPC_CLIENT_CONNECTED) { |
| 165 | atomic_inc(&bundle->usage); |
| 166 | rx->bundle = bundle; |
| 167 | } |
| 168 | _leave(" = %p [second %d]", bundle, atomic_read(&bundle->usage)); |
| 169 | return bundle; |
| 170 | } |
| 171 | |
| 172 | /* |
| 173 | * release a bundle |
| 174 | */ |
| 175 | void rxrpc_put_bundle(struct rxrpc_transport *trans, |
| 176 | struct rxrpc_conn_bundle *bundle) |
| 177 | { |
| 178 | _enter("%p,%p{%d}",trans, bundle, atomic_read(&bundle->usage)); |
| 179 | |
| 180 | if (atomic_dec_and_lock(&bundle->usage, &trans->client_lock)) { |
| 181 | _debug("Destroy bundle"); |
| 182 | rb_erase(&bundle->node, &trans->bundles); |
| 183 | spin_unlock(&trans->client_lock); |
| 184 | ASSERT(list_empty(&bundle->unused_conns)); |
| 185 | ASSERT(list_empty(&bundle->avail_conns)); |
| 186 | ASSERT(list_empty(&bundle->busy_conns)); |
| 187 | ASSERTCMP(bundle->num_conns, ==, 0); |
| 188 | key_put(bundle->key); |
| 189 | kfree(bundle); |
| 190 | } |
| 191 | |
| 192 | _leave(""); |
| 193 | } |
| 194 | |
| 195 | /* |
| 196 | * allocate a new connection |
| 197 | */ |
| 198 | static struct rxrpc_connection *rxrpc_alloc_connection(gfp_t gfp) |
| 199 | { |
| 200 | struct rxrpc_connection *conn; |
| 201 | |
| 202 | _enter(""); |
| 203 | |
| 204 | conn = kzalloc(sizeof(struct rxrpc_connection), gfp); |
| 205 | if (conn) { |
| 206 | INIT_WORK(&conn->processor, &rxrpc_process_connection); |
| 207 | INIT_LIST_HEAD(&conn->bundle_link); |
| 208 | conn->calls = RB_ROOT; |
| 209 | skb_queue_head_init(&conn->rx_queue); |
| 210 | rwlock_init(&conn->lock); |
| 211 | spin_lock_init(&conn->state_lock); |
| 212 | atomic_set(&conn->usage, 1); |
| 213 | conn->debug_id = atomic_inc_return(&rxrpc_debug_id); |
| 214 | conn->avail_calls = RXRPC_MAXCALLS; |
| 215 | conn->size_align = 4; |
| 216 | conn->header_size = sizeof(struct rxrpc_header); |
| 217 | } |
| 218 | |
Adrian Bunk | 16c61ad | 2007-06-15 15:15:43 -0700 | [diff] [blame] | 219 | _leave(" = %p{%d}", conn, conn ? conn->debug_id : 0); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 220 | return conn; |
| 221 | } |
| 222 | |
| 223 | /* |
| 224 | * assign a connection ID to a connection and add it to the transport's |
| 225 | * connection lookup tree |
| 226 | * - called with transport client lock held |
| 227 | */ |
| 228 | static void rxrpc_assign_connection_id(struct rxrpc_connection *conn) |
| 229 | { |
| 230 | struct rxrpc_connection *xconn; |
| 231 | struct rb_node *parent, **p; |
| 232 | __be32 epoch; |
| 233 | u32 real_conn_id; |
| 234 | |
| 235 | _enter(""); |
| 236 | |
| 237 | epoch = conn->epoch; |
| 238 | |
| 239 | write_lock_bh(&conn->trans->conn_lock); |
| 240 | |
| 241 | conn->trans->conn_idcounter += RXRPC_CID_INC; |
| 242 | if (conn->trans->conn_idcounter < RXRPC_CID_INC) |
| 243 | conn->trans->conn_idcounter = RXRPC_CID_INC; |
| 244 | real_conn_id = conn->trans->conn_idcounter; |
| 245 | |
| 246 | attempt_insertion: |
| 247 | parent = NULL; |
| 248 | p = &conn->trans->client_conns.rb_node; |
| 249 | |
| 250 | while (*p) { |
| 251 | parent = *p; |
| 252 | xconn = rb_entry(parent, struct rxrpc_connection, node); |
| 253 | |
| 254 | if (epoch < xconn->epoch) |
| 255 | p = &(*p)->rb_left; |
| 256 | else if (epoch > xconn->epoch) |
| 257 | p = &(*p)->rb_right; |
| 258 | else if (real_conn_id < xconn->real_conn_id) |
| 259 | p = &(*p)->rb_left; |
| 260 | else if (real_conn_id > xconn->real_conn_id) |
| 261 | p = &(*p)->rb_right; |
| 262 | else |
| 263 | goto id_exists; |
| 264 | } |
| 265 | |
| 266 | /* we've found a suitable hole - arrange for this connection to occupy |
| 267 | * it */ |
| 268 | rb_link_node(&conn->node, parent, p); |
| 269 | rb_insert_color(&conn->node, &conn->trans->client_conns); |
| 270 | |
| 271 | conn->real_conn_id = real_conn_id; |
| 272 | conn->cid = htonl(real_conn_id); |
| 273 | write_unlock_bh(&conn->trans->conn_lock); |
| 274 | _leave(" [CONNID %x CID %x]", real_conn_id, ntohl(conn->cid)); |
| 275 | return; |
| 276 | |
| 277 | /* we found a connection with the proposed ID - walk the tree from that |
| 278 | * point looking for the next unused ID */ |
| 279 | id_exists: |
| 280 | for (;;) { |
| 281 | real_conn_id += RXRPC_CID_INC; |
| 282 | if (real_conn_id < RXRPC_CID_INC) { |
| 283 | real_conn_id = RXRPC_CID_INC; |
| 284 | conn->trans->conn_idcounter = real_conn_id; |
| 285 | goto attempt_insertion; |
| 286 | } |
| 287 | |
| 288 | parent = rb_next(parent); |
| 289 | if (!parent) |
| 290 | goto attempt_insertion; |
| 291 | |
| 292 | xconn = rb_entry(parent, struct rxrpc_connection, node); |
| 293 | if (epoch < xconn->epoch || |
| 294 | real_conn_id < xconn->real_conn_id) |
| 295 | goto attempt_insertion; |
| 296 | } |
| 297 | } |
| 298 | |
| 299 | /* |
| 300 | * add a call to a connection's call-by-ID tree |
| 301 | */ |
| 302 | static void rxrpc_add_call_ID_to_conn(struct rxrpc_connection *conn, |
| 303 | struct rxrpc_call *call) |
| 304 | { |
| 305 | struct rxrpc_call *xcall; |
| 306 | struct rb_node *parent, **p; |
| 307 | __be32 call_id; |
| 308 | |
| 309 | write_lock_bh(&conn->lock); |
| 310 | |
| 311 | call_id = call->call_id; |
| 312 | p = &conn->calls.rb_node; |
| 313 | parent = NULL; |
| 314 | while (*p) { |
| 315 | parent = *p; |
| 316 | xcall = rb_entry(parent, struct rxrpc_call, conn_node); |
| 317 | |
| 318 | if (call_id < xcall->call_id) |
| 319 | p = &(*p)->rb_left; |
| 320 | else if (call_id > xcall->call_id) |
| 321 | p = &(*p)->rb_right; |
| 322 | else |
| 323 | BUG(); |
| 324 | } |
| 325 | |
| 326 | rb_link_node(&call->conn_node, parent, p); |
| 327 | rb_insert_color(&call->conn_node, &conn->calls); |
| 328 | |
| 329 | write_unlock_bh(&conn->lock); |
| 330 | } |
| 331 | |
| 332 | /* |
| 333 | * connect a call on an exclusive connection |
| 334 | */ |
| 335 | static int rxrpc_connect_exclusive(struct rxrpc_sock *rx, |
| 336 | struct rxrpc_transport *trans, |
| 337 | __be16 service_id, |
| 338 | struct rxrpc_call *call, |
| 339 | gfp_t gfp) |
| 340 | { |
| 341 | struct rxrpc_connection *conn; |
| 342 | int chan, ret; |
| 343 | |
| 344 | _enter(""); |
| 345 | |
| 346 | conn = rx->conn; |
| 347 | if (!conn) { |
| 348 | /* not yet present - create a candidate for a new connection |
| 349 | * and then redo the check */ |
| 350 | conn = rxrpc_alloc_connection(gfp); |
Dan Carpenter | 0975ecb | 2009-05-21 15:22:02 -0700 | [diff] [blame] | 351 | if (!conn) { |
| 352 | _leave(" = -ENOMEM"); |
| 353 | return -ENOMEM; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 354 | } |
| 355 | |
| 356 | conn->trans = trans; |
| 357 | conn->bundle = NULL; |
| 358 | conn->service_id = service_id; |
| 359 | conn->epoch = rxrpc_epoch; |
| 360 | conn->in_clientflag = 0; |
| 361 | conn->out_clientflag = RXRPC_CLIENT_INITIATED; |
| 362 | conn->cid = 0; |
| 363 | conn->state = RXRPC_CONN_CLIENT; |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 364 | conn->avail_calls = RXRPC_MAXCALLS - 1; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 365 | conn->security_level = rx->min_sec_level; |
| 366 | conn->key = key_get(rx->key); |
| 367 | |
| 368 | ret = rxrpc_init_client_conn_security(conn); |
| 369 | if (ret < 0) { |
| 370 | key_put(conn->key); |
| 371 | kfree(conn); |
| 372 | _leave(" = %d [key]", ret); |
| 373 | return ret; |
| 374 | } |
| 375 | |
| 376 | write_lock_bh(&rxrpc_connection_lock); |
| 377 | list_add_tail(&conn->link, &rxrpc_connections); |
| 378 | write_unlock_bh(&rxrpc_connection_lock); |
| 379 | |
| 380 | spin_lock(&trans->client_lock); |
| 381 | atomic_inc(&trans->usage); |
| 382 | |
| 383 | _net("CONNECT EXCL new %d on TRANS %d", |
| 384 | conn->debug_id, conn->trans->debug_id); |
| 385 | |
| 386 | rxrpc_assign_connection_id(conn); |
| 387 | rx->conn = conn; |
Alexey Khoroshilov | 8f22ba6 | 2014-01-26 11:39:26 +0000 | [diff] [blame] | 388 | } else { |
| 389 | spin_lock(&trans->client_lock); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 390 | } |
| 391 | |
| 392 | /* we've got a connection with a free channel and we can now attach the |
| 393 | * call to it |
| 394 | * - we're holding the transport's client lock |
| 395 | * - we're holding a reference on the connection |
| 396 | */ |
| 397 | for (chan = 0; chan < RXRPC_MAXCALLS; chan++) |
| 398 | if (!conn->channels[chan]) |
| 399 | goto found_channel; |
| 400 | goto no_free_channels; |
| 401 | |
| 402 | found_channel: |
| 403 | atomic_inc(&conn->usage); |
| 404 | conn->channels[chan] = call; |
| 405 | call->conn = conn; |
| 406 | call->channel = chan; |
| 407 | call->cid = conn->cid | htonl(chan); |
| 408 | call->call_id = htonl(++conn->call_counter); |
| 409 | |
| 410 | _net("CONNECT client on conn %d chan %d as call %x", |
| 411 | conn->debug_id, chan, ntohl(call->call_id)); |
| 412 | |
| 413 | spin_unlock(&trans->client_lock); |
| 414 | |
| 415 | rxrpc_add_call_ID_to_conn(conn, call); |
| 416 | _leave(" = 0"); |
| 417 | return 0; |
| 418 | |
| 419 | no_free_channels: |
| 420 | spin_unlock(&trans->client_lock); |
| 421 | _leave(" = -ENOSR"); |
| 422 | return -ENOSR; |
| 423 | } |
| 424 | |
| 425 | /* |
| 426 | * find a connection for a call |
| 427 | * - called in process context with IRQs enabled |
| 428 | */ |
| 429 | int rxrpc_connect_call(struct rxrpc_sock *rx, |
| 430 | struct rxrpc_transport *trans, |
| 431 | struct rxrpc_conn_bundle *bundle, |
| 432 | struct rxrpc_call *call, |
| 433 | gfp_t gfp) |
| 434 | { |
| 435 | struct rxrpc_connection *conn, *candidate; |
| 436 | int chan, ret; |
| 437 | |
| 438 | DECLARE_WAITQUEUE(myself, current); |
| 439 | |
| 440 | _enter("%p,%lx,", rx, call->user_call_ID); |
| 441 | |
| 442 | if (test_bit(RXRPC_SOCK_EXCLUSIVE_CONN, &rx->flags)) |
| 443 | return rxrpc_connect_exclusive(rx, trans, bundle->service_id, |
| 444 | call, gfp); |
| 445 | |
| 446 | spin_lock(&trans->client_lock); |
| 447 | for (;;) { |
| 448 | /* see if the bundle has a call slot available */ |
| 449 | if (!list_empty(&bundle->avail_conns)) { |
| 450 | _debug("avail"); |
| 451 | conn = list_entry(bundle->avail_conns.next, |
| 452 | struct rxrpc_connection, |
| 453 | bundle_link); |
David Howells | 519d256 | 2009-06-16 21:36:44 +0100 | [diff] [blame] | 454 | if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) { |
| 455 | list_del_init(&conn->bundle_link); |
| 456 | bundle->num_conns--; |
| 457 | continue; |
| 458 | } |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 459 | if (--conn->avail_calls == 0) |
| 460 | list_move(&conn->bundle_link, |
| 461 | &bundle->busy_conns); |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 462 | ASSERTCMP(conn->avail_calls, <, RXRPC_MAXCALLS); |
| 463 | ASSERT(conn->channels[0] == NULL || |
| 464 | conn->channels[1] == NULL || |
| 465 | conn->channels[2] == NULL || |
| 466 | conn->channels[3] == NULL); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 467 | atomic_inc(&conn->usage); |
| 468 | break; |
| 469 | } |
| 470 | |
| 471 | if (!list_empty(&bundle->unused_conns)) { |
| 472 | _debug("unused"); |
| 473 | conn = list_entry(bundle->unused_conns.next, |
| 474 | struct rxrpc_connection, |
| 475 | bundle_link); |
David Howells | 519d256 | 2009-06-16 21:36:44 +0100 | [diff] [blame] | 476 | if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) { |
| 477 | list_del_init(&conn->bundle_link); |
| 478 | bundle->num_conns--; |
| 479 | continue; |
| 480 | } |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 481 | ASSERTCMP(conn->avail_calls, ==, RXRPC_MAXCALLS); |
| 482 | conn->avail_calls = RXRPC_MAXCALLS - 1; |
| 483 | ASSERT(conn->channels[0] == NULL && |
| 484 | conn->channels[1] == NULL && |
| 485 | conn->channels[2] == NULL && |
| 486 | conn->channels[3] == NULL); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 487 | atomic_inc(&conn->usage); |
| 488 | list_move(&conn->bundle_link, &bundle->avail_conns); |
| 489 | break; |
| 490 | } |
| 491 | |
| 492 | /* need to allocate a new connection */ |
| 493 | _debug("get new conn [%d]", bundle->num_conns); |
| 494 | |
| 495 | spin_unlock(&trans->client_lock); |
| 496 | |
| 497 | if (signal_pending(current)) |
| 498 | goto interrupted; |
| 499 | |
| 500 | if (bundle->num_conns >= 20) { |
| 501 | _debug("too many conns"); |
| 502 | |
Mel Gorman | d0164ad | 2015-11-06 16:28:21 -0800 | [diff] [blame^] | 503 | if (!gfpflags_allow_blocking(gfp)) { |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 504 | _leave(" = -EAGAIN"); |
| 505 | return -EAGAIN; |
| 506 | } |
| 507 | |
| 508 | add_wait_queue(&bundle->chanwait, &myself); |
| 509 | for (;;) { |
| 510 | set_current_state(TASK_INTERRUPTIBLE); |
| 511 | if (bundle->num_conns < 20 || |
| 512 | !list_empty(&bundle->unused_conns) || |
| 513 | !list_empty(&bundle->avail_conns)) |
| 514 | break; |
| 515 | if (signal_pending(current)) |
| 516 | goto interrupted_dequeue; |
| 517 | schedule(); |
| 518 | } |
| 519 | remove_wait_queue(&bundle->chanwait, &myself); |
| 520 | __set_current_state(TASK_RUNNING); |
| 521 | spin_lock(&trans->client_lock); |
| 522 | continue; |
| 523 | } |
| 524 | |
| 525 | /* not yet present - create a candidate for a new connection and then |
| 526 | * redo the check */ |
| 527 | candidate = rxrpc_alloc_connection(gfp); |
Dan Carpenter | 0975ecb | 2009-05-21 15:22:02 -0700 | [diff] [blame] | 528 | if (!candidate) { |
| 529 | _leave(" = -ENOMEM"); |
| 530 | return -ENOMEM; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 531 | } |
| 532 | |
| 533 | candidate->trans = trans; |
| 534 | candidate->bundle = bundle; |
| 535 | candidate->service_id = bundle->service_id; |
| 536 | candidate->epoch = rxrpc_epoch; |
| 537 | candidate->in_clientflag = 0; |
| 538 | candidate->out_clientflag = RXRPC_CLIENT_INITIATED; |
| 539 | candidate->cid = 0; |
| 540 | candidate->state = RXRPC_CONN_CLIENT; |
| 541 | candidate->avail_calls = RXRPC_MAXCALLS; |
| 542 | candidate->security_level = rx->min_sec_level; |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 543 | candidate->key = key_get(bundle->key); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 544 | |
| 545 | ret = rxrpc_init_client_conn_security(candidate); |
| 546 | if (ret < 0) { |
| 547 | key_put(candidate->key); |
| 548 | kfree(candidate); |
| 549 | _leave(" = %d [key]", ret); |
| 550 | return ret; |
| 551 | } |
| 552 | |
| 553 | write_lock_bh(&rxrpc_connection_lock); |
| 554 | list_add_tail(&candidate->link, &rxrpc_connections); |
| 555 | write_unlock_bh(&rxrpc_connection_lock); |
| 556 | |
| 557 | spin_lock(&trans->client_lock); |
| 558 | |
| 559 | list_add(&candidate->bundle_link, &bundle->unused_conns); |
| 560 | bundle->num_conns++; |
| 561 | atomic_inc(&bundle->usage); |
| 562 | atomic_inc(&trans->usage); |
| 563 | |
| 564 | _net("CONNECT new %d on TRANS %d", |
| 565 | candidate->debug_id, candidate->trans->debug_id); |
| 566 | |
| 567 | rxrpc_assign_connection_id(candidate); |
| 568 | if (candidate->security) |
| 569 | candidate->security->prime_packet_security(candidate); |
| 570 | |
| 571 | /* leave the candidate lurking in zombie mode attached to the |
| 572 | * bundle until we're ready for it */ |
| 573 | rxrpc_put_connection(candidate); |
| 574 | candidate = NULL; |
| 575 | } |
| 576 | |
| 577 | /* we've got a connection with a free channel and we can now attach the |
| 578 | * call to it |
| 579 | * - we're holding the transport's client lock |
| 580 | * - we're holding a reference on the connection |
| 581 | * - we're holding a reference on the bundle |
| 582 | */ |
| 583 | for (chan = 0; chan < RXRPC_MAXCALLS; chan++) |
| 584 | if (!conn->channels[chan]) |
| 585 | goto found_channel; |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 586 | ASSERT(conn->channels[0] == NULL || |
| 587 | conn->channels[1] == NULL || |
| 588 | conn->channels[2] == NULL || |
| 589 | conn->channels[3] == NULL); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 590 | BUG(); |
| 591 | |
| 592 | found_channel: |
| 593 | conn->channels[chan] = call; |
| 594 | call->conn = conn; |
| 595 | call->channel = chan; |
| 596 | call->cid = conn->cid | htonl(chan); |
| 597 | call->call_id = htonl(++conn->call_counter); |
| 598 | |
| 599 | _net("CONNECT client on conn %d chan %d as call %x", |
| 600 | conn->debug_id, chan, ntohl(call->call_id)); |
| 601 | |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 602 | ASSERTCMP(conn->avail_calls, <, RXRPC_MAXCALLS); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 603 | spin_unlock(&trans->client_lock); |
| 604 | |
| 605 | rxrpc_add_call_ID_to_conn(conn, call); |
| 606 | |
| 607 | _leave(" = 0"); |
| 608 | return 0; |
| 609 | |
| 610 | interrupted_dequeue: |
| 611 | remove_wait_queue(&bundle->chanwait, &myself); |
| 612 | __set_current_state(TASK_RUNNING); |
| 613 | interrupted: |
| 614 | _leave(" = -ERESTARTSYS"); |
| 615 | return -ERESTARTSYS; |
| 616 | } |
| 617 | |
| 618 | /* |
| 619 | * get a record of an incoming connection |
| 620 | */ |
| 621 | struct rxrpc_connection * |
| 622 | rxrpc_incoming_connection(struct rxrpc_transport *trans, |
| 623 | struct rxrpc_header *hdr, |
| 624 | gfp_t gfp) |
| 625 | { |
| 626 | struct rxrpc_connection *conn, *candidate = NULL; |
| 627 | struct rb_node *p, **pp; |
| 628 | const char *new = "old"; |
| 629 | __be32 epoch; |
| 630 | u32 conn_id; |
| 631 | |
| 632 | _enter(""); |
| 633 | |
| 634 | ASSERT(hdr->flags & RXRPC_CLIENT_INITIATED); |
| 635 | |
| 636 | epoch = hdr->epoch; |
| 637 | conn_id = ntohl(hdr->cid) & RXRPC_CIDMASK; |
| 638 | |
| 639 | /* search the connection list first */ |
| 640 | read_lock_bh(&trans->conn_lock); |
| 641 | |
| 642 | p = trans->server_conns.rb_node; |
| 643 | while (p) { |
| 644 | conn = rb_entry(p, struct rxrpc_connection, node); |
| 645 | |
| 646 | _debug("maybe %x", conn->real_conn_id); |
| 647 | |
| 648 | if (epoch < conn->epoch) |
| 649 | p = p->rb_left; |
| 650 | else if (epoch > conn->epoch) |
| 651 | p = p->rb_right; |
| 652 | else if (conn_id < conn->real_conn_id) |
| 653 | p = p->rb_left; |
| 654 | else if (conn_id > conn->real_conn_id) |
| 655 | p = p->rb_right; |
| 656 | else |
| 657 | goto found_extant_connection; |
| 658 | } |
| 659 | read_unlock_bh(&trans->conn_lock); |
| 660 | |
| 661 | /* not yet present - create a candidate for a new record and then |
| 662 | * redo the search */ |
| 663 | candidate = rxrpc_alloc_connection(gfp); |
| 664 | if (!candidate) { |
| 665 | _leave(" = -ENOMEM"); |
| 666 | return ERR_PTR(-ENOMEM); |
| 667 | } |
| 668 | |
| 669 | candidate->trans = trans; |
| 670 | candidate->epoch = hdr->epoch; |
YOSHIFUJI Hideaki | ae445d1 | 2007-12-12 03:55:22 +0900 | [diff] [blame] | 671 | candidate->cid = hdr->cid & cpu_to_be32(RXRPC_CIDMASK); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 672 | candidate->service_id = hdr->serviceId; |
| 673 | candidate->security_ix = hdr->securityIndex; |
| 674 | candidate->in_clientflag = RXRPC_CLIENT_INITIATED; |
| 675 | candidate->out_clientflag = 0; |
| 676 | candidate->real_conn_id = conn_id; |
| 677 | candidate->state = RXRPC_CONN_SERVER; |
| 678 | if (candidate->service_id) |
| 679 | candidate->state = RXRPC_CONN_SERVER_UNSECURED; |
| 680 | |
| 681 | write_lock_bh(&trans->conn_lock); |
| 682 | |
| 683 | pp = &trans->server_conns.rb_node; |
| 684 | p = NULL; |
| 685 | while (*pp) { |
| 686 | p = *pp; |
| 687 | conn = rb_entry(p, struct rxrpc_connection, node); |
| 688 | |
| 689 | if (epoch < conn->epoch) |
| 690 | pp = &(*pp)->rb_left; |
| 691 | else if (epoch > conn->epoch) |
| 692 | pp = &(*pp)->rb_right; |
| 693 | else if (conn_id < conn->real_conn_id) |
| 694 | pp = &(*pp)->rb_left; |
| 695 | else if (conn_id > conn->real_conn_id) |
| 696 | pp = &(*pp)->rb_right; |
| 697 | else |
| 698 | goto found_extant_second; |
| 699 | } |
| 700 | |
| 701 | /* we can now add the new candidate to the list */ |
| 702 | conn = candidate; |
| 703 | candidate = NULL; |
| 704 | rb_link_node(&conn->node, p, pp); |
| 705 | rb_insert_color(&conn->node, &trans->server_conns); |
| 706 | atomic_inc(&conn->trans->usage); |
| 707 | |
| 708 | write_unlock_bh(&trans->conn_lock); |
| 709 | |
| 710 | write_lock_bh(&rxrpc_connection_lock); |
| 711 | list_add_tail(&conn->link, &rxrpc_connections); |
| 712 | write_unlock_bh(&rxrpc_connection_lock); |
| 713 | |
| 714 | new = "new"; |
| 715 | |
| 716 | success: |
| 717 | _net("CONNECTION %s %d {%x}", new, conn->debug_id, conn->real_conn_id); |
| 718 | |
| 719 | _leave(" = %p {u=%d}", conn, atomic_read(&conn->usage)); |
| 720 | return conn; |
| 721 | |
| 722 | /* we found the connection in the list immediately */ |
| 723 | found_extant_connection: |
| 724 | if (hdr->securityIndex != conn->security_ix) { |
| 725 | read_unlock_bh(&trans->conn_lock); |
| 726 | goto security_mismatch; |
| 727 | } |
| 728 | atomic_inc(&conn->usage); |
| 729 | read_unlock_bh(&trans->conn_lock); |
| 730 | goto success; |
| 731 | |
| 732 | /* we found the connection on the second time through the list */ |
| 733 | found_extant_second: |
| 734 | if (hdr->securityIndex != conn->security_ix) { |
| 735 | write_unlock_bh(&trans->conn_lock); |
| 736 | goto security_mismatch; |
| 737 | } |
| 738 | atomic_inc(&conn->usage); |
| 739 | write_unlock_bh(&trans->conn_lock); |
| 740 | kfree(candidate); |
| 741 | goto success; |
| 742 | |
| 743 | security_mismatch: |
| 744 | kfree(candidate); |
| 745 | _leave(" = -EKEYREJECTED"); |
| 746 | return ERR_PTR(-EKEYREJECTED); |
| 747 | } |
| 748 | |
| 749 | /* |
| 750 | * find a connection based on transport and RxRPC connection ID for an incoming |
| 751 | * packet |
| 752 | */ |
| 753 | struct rxrpc_connection *rxrpc_find_connection(struct rxrpc_transport *trans, |
| 754 | struct rxrpc_header *hdr) |
| 755 | { |
| 756 | struct rxrpc_connection *conn; |
| 757 | struct rb_node *p; |
| 758 | __be32 epoch; |
| 759 | u32 conn_id; |
| 760 | |
| 761 | _enter(",{%x,%x}", ntohl(hdr->cid), hdr->flags); |
| 762 | |
| 763 | read_lock_bh(&trans->conn_lock); |
| 764 | |
| 765 | conn_id = ntohl(hdr->cid) & RXRPC_CIDMASK; |
| 766 | epoch = hdr->epoch; |
| 767 | |
| 768 | if (hdr->flags & RXRPC_CLIENT_INITIATED) |
| 769 | p = trans->server_conns.rb_node; |
| 770 | else |
| 771 | p = trans->client_conns.rb_node; |
| 772 | |
| 773 | while (p) { |
| 774 | conn = rb_entry(p, struct rxrpc_connection, node); |
| 775 | |
| 776 | _debug("maybe %x", conn->real_conn_id); |
| 777 | |
| 778 | if (epoch < conn->epoch) |
| 779 | p = p->rb_left; |
| 780 | else if (epoch > conn->epoch) |
| 781 | p = p->rb_right; |
| 782 | else if (conn_id < conn->real_conn_id) |
| 783 | p = p->rb_left; |
| 784 | else if (conn_id > conn->real_conn_id) |
| 785 | p = p->rb_right; |
| 786 | else |
| 787 | goto found; |
| 788 | } |
| 789 | |
| 790 | read_unlock_bh(&trans->conn_lock); |
| 791 | _leave(" = NULL"); |
| 792 | return NULL; |
| 793 | |
| 794 | found: |
| 795 | atomic_inc(&conn->usage); |
| 796 | read_unlock_bh(&trans->conn_lock); |
| 797 | _leave(" = %p", conn); |
| 798 | return conn; |
| 799 | } |
| 800 | |
| 801 | /* |
| 802 | * release a virtual connection |
| 803 | */ |
| 804 | void rxrpc_put_connection(struct rxrpc_connection *conn) |
| 805 | { |
| 806 | _enter("%p{u=%d,d=%d}", |
| 807 | conn, atomic_read(&conn->usage), conn->debug_id); |
| 808 | |
| 809 | ASSERTCMP(atomic_read(&conn->usage), >, 0); |
| 810 | |
Ksenija Stanojevic | 22a3f9a | 2015-09-17 18:12:53 +0200 | [diff] [blame] | 811 | conn->put_time = ktime_get_seconds(); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 812 | if (atomic_dec_and_test(&conn->usage)) { |
| 813 | _debug("zombie"); |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 814 | rxrpc_queue_delayed_work(&rxrpc_connection_reap, 0); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 815 | } |
| 816 | |
| 817 | _leave(""); |
| 818 | } |
| 819 | |
| 820 | /* |
| 821 | * destroy a virtual connection |
| 822 | */ |
| 823 | static void rxrpc_destroy_connection(struct rxrpc_connection *conn) |
| 824 | { |
| 825 | _enter("%p{%d}", conn, atomic_read(&conn->usage)); |
| 826 | |
| 827 | ASSERTCMP(atomic_read(&conn->usage), ==, 0); |
| 828 | |
| 829 | _net("DESTROY CONN %d", conn->debug_id); |
| 830 | |
| 831 | if (conn->bundle) |
| 832 | rxrpc_put_bundle(conn->trans, conn->bundle); |
| 833 | |
| 834 | ASSERT(RB_EMPTY_ROOT(&conn->calls)); |
| 835 | rxrpc_purge_queue(&conn->rx_queue); |
| 836 | |
| 837 | rxrpc_clear_conn_security(conn); |
| 838 | rxrpc_put_transport(conn->trans); |
| 839 | kfree(conn); |
| 840 | _leave(""); |
| 841 | } |
| 842 | |
| 843 | /* |
| 844 | * reap dead connections |
| 845 | */ |
Roel Kluin | 5eaa65b | 2008-12-10 15:18:31 -0800 | [diff] [blame] | 846 | static void rxrpc_connection_reaper(struct work_struct *work) |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 847 | { |
| 848 | struct rxrpc_connection *conn, *_p; |
| 849 | unsigned long now, earliest, reap_time; |
| 850 | |
| 851 | LIST_HEAD(graveyard); |
| 852 | |
| 853 | _enter(""); |
| 854 | |
Ksenija Stanojevic | 22a3f9a | 2015-09-17 18:12:53 +0200 | [diff] [blame] | 855 | now = ktime_get_seconds(); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 856 | earliest = ULONG_MAX; |
| 857 | |
| 858 | write_lock_bh(&rxrpc_connection_lock); |
| 859 | list_for_each_entry_safe(conn, _p, &rxrpc_connections, link) { |
| 860 | _debug("reap CONN %d { u=%d,t=%ld }", |
| 861 | conn->debug_id, atomic_read(&conn->usage), |
| 862 | (long) now - (long) conn->put_time); |
| 863 | |
| 864 | if (likely(atomic_read(&conn->usage) > 0)) |
| 865 | continue; |
| 866 | |
| 867 | spin_lock(&conn->trans->client_lock); |
| 868 | write_lock(&conn->trans->conn_lock); |
David Howells | 5873c08 | 2014-02-07 18:58:44 +0000 | [diff] [blame] | 869 | reap_time = conn->put_time + rxrpc_connection_expiry; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 870 | |
| 871 | if (atomic_read(&conn->usage) > 0) { |
| 872 | ; |
| 873 | } else if (reap_time <= now) { |
| 874 | list_move_tail(&conn->link, &graveyard); |
| 875 | if (conn->out_clientflag) |
| 876 | rb_erase(&conn->node, |
| 877 | &conn->trans->client_conns); |
| 878 | else |
| 879 | rb_erase(&conn->node, |
| 880 | &conn->trans->server_conns); |
| 881 | if (conn->bundle) { |
| 882 | list_del_init(&conn->bundle_link); |
| 883 | conn->bundle->num_conns--; |
| 884 | } |
| 885 | |
| 886 | } else if (reap_time < earliest) { |
| 887 | earliest = reap_time; |
| 888 | } |
| 889 | |
| 890 | write_unlock(&conn->trans->conn_lock); |
| 891 | spin_unlock(&conn->trans->client_lock); |
| 892 | } |
| 893 | write_unlock_bh(&rxrpc_connection_lock); |
| 894 | |
| 895 | if (earliest != ULONG_MAX) { |
| 896 | _debug("reschedule reaper %ld", (long) earliest - now); |
| 897 | ASSERTCMP(earliest, >, now); |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 898 | rxrpc_queue_delayed_work(&rxrpc_connection_reap, |
| 899 | (earliest - now) * HZ); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 900 | } |
| 901 | |
| 902 | /* then destroy all those pulled out */ |
| 903 | while (!list_empty(&graveyard)) { |
| 904 | conn = list_entry(graveyard.next, struct rxrpc_connection, |
| 905 | link); |
| 906 | list_del_init(&conn->link); |
| 907 | |
| 908 | ASSERTCMP(atomic_read(&conn->usage), ==, 0); |
| 909 | rxrpc_destroy_connection(conn); |
| 910 | } |
| 911 | |
| 912 | _leave(""); |
| 913 | } |
| 914 | |
| 915 | /* |
| 916 | * preemptively destroy all the connection records rather than waiting for them |
| 917 | * to time out |
| 918 | */ |
| 919 | void __exit rxrpc_destroy_all_connections(void) |
| 920 | { |
| 921 | _enter(""); |
| 922 | |
David Howells | 5873c08 | 2014-02-07 18:58:44 +0000 | [diff] [blame] | 923 | rxrpc_connection_expiry = 0; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 924 | cancel_delayed_work(&rxrpc_connection_reap); |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 925 | rxrpc_queue_delayed_work(&rxrpc_connection_reap, 0); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 926 | |
| 927 | _leave(""); |
| 928 | } |