David Howells | 08e0e7c | 2007-04-26 15:55:03 -0700 | [diff] [blame^] | 1 | /* Maintain an RxRPC server socket to do AFS communications through |
| 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 <net/sock.h> |
| 13 | #include <net/af_rxrpc.h> |
| 14 | #include <rxrpc/packet.h> |
| 15 | #include "internal.h" |
| 16 | #include "afs_cm.h" |
| 17 | |
| 18 | static struct socket *afs_socket; /* my RxRPC socket */ |
| 19 | static struct workqueue_struct *afs_async_calls; |
| 20 | |
| 21 | static void afs_wake_up_call_waiter(struct afs_call *); |
| 22 | static int afs_wait_for_call_to_complete(struct afs_call *); |
| 23 | static void afs_wake_up_async_call(struct afs_call *); |
| 24 | static int afs_dont_wait_for_call_to_complete(struct afs_call *); |
| 25 | static void afs_process_async_call(struct work_struct *); |
| 26 | static void afs_rx_interceptor(struct sock *, unsigned long, struct sk_buff *); |
| 27 | static int afs_deliver_cm_op_id(struct afs_call *, struct sk_buff *, bool); |
| 28 | |
| 29 | /* synchronous call management */ |
| 30 | const struct afs_wait_mode afs_sync_call = { |
| 31 | .rx_wakeup = afs_wake_up_call_waiter, |
| 32 | .wait = afs_wait_for_call_to_complete, |
| 33 | }; |
| 34 | |
| 35 | /* asynchronous call management */ |
| 36 | const struct afs_wait_mode afs_async_call = { |
| 37 | .rx_wakeup = afs_wake_up_async_call, |
| 38 | .wait = afs_dont_wait_for_call_to_complete, |
| 39 | }; |
| 40 | |
| 41 | /* asynchronous incoming call management */ |
| 42 | static const struct afs_wait_mode afs_async_incoming_call = { |
| 43 | .rx_wakeup = afs_wake_up_async_call, |
| 44 | }; |
| 45 | |
| 46 | /* asynchronous incoming call initial processing */ |
| 47 | static const struct afs_call_type afs_RXCMxxxx = { |
| 48 | .deliver = afs_deliver_cm_op_id, |
| 49 | .abort_to_error = afs_abort_to_error, |
| 50 | }; |
| 51 | |
| 52 | static void afs_collect_incoming_call(struct work_struct *); |
| 53 | |
| 54 | static struct sk_buff_head afs_incoming_calls; |
| 55 | static DECLARE_WORK(afs_collect_incoming_call_work, afs_collect_incoming_call); |
| 56 | |
| 57 | /* |
| 58 | * open an RxRPC socket and bind it to be a server for callback notifications |
| 59 | * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT |
| 60 | */ |
| 61 | int afs_open_socket(void) |
| 62 | { |
| 63 | struct sockaddr_rxrpc srx; |
| 64 | struct socket *socket; |
| 65 | int ret; |
| 66 | |
| 67 | _enter(""); |
| 68 | |
| 69 | skb_queue_head_init(&afs_incoming_calls); |
| 70 | |
| 71 | afs_async_calls = create_singlethread_workqueue("kafsd"); |
| 72 | if (!afs_async_calls) { |
| 73 | _leave(" = -ENOMEM [wq]"); |
| 74 | return -ENOMEM; |
| 75 | } |
| 76 | |
| 77 | ret = sock_create_kern(AF_RXRPC, SOCK_DGRAM, PF_INET, &socket); |
| 78 | if (ret < 0) { |
| 79 | destroy_workqueue(afs_async_calls); |
| 80 | _leave(" = %d [socket]", ret); |
| 81 | return ret; |
| 82 | } |
| 83 | |
| 84 | socket->sk->sk_allocation = GFP_NOFS; |
| 85 | |
| 86 | /* bind the callback manager's address to make this a server socket */ |
| 87 | srx.srx_family = AF_RXRPC; |
| 88 | srx.srx_service = CM_SERVICE; |
| 89 | srx.transport_type = SOCK_DGRAM; |
| 90 | srx.transport_len = sizeof(srx.transport.sin); |
| 91 | srx.transport.sin.sin_family = AF_INET; |
| 92 | srx.transport.sin.sin_port = htons(AFS_CM_PORT); |
| 93 | memset(&srx.transport.sin.sin_addr, 0, |
| 94 | sizeof(srx.transport.sin.sin_addr)); |
| 95 | |
| 96 | ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); |
| 97 | if (ret < 0) { |
| 98 | sock_release(socket); |
| 99 | _leave(" = %d [bind]", ret); |
| 100 | return ret; |
| 101 | } |
| 102 | |
| 103 | rxrpc_kernel_intercept_rx_messages(socket, afs_rx_interceptor); |
| 104 | |
| 105 | afs_socket = socket; |
| 106 | _leave(" = 0"); |
| 107 | return 0; |
| 108 | } |
| 109 | |
| 110 | /* |
| 111 | * close the RxRPC socket AFS was using |
| 112 | */ |
| 113 | void afs_close_socket(void) |
| 114 | { |
| 115 | _enter(""); |
| 116 | |
| 117 | sock_release(afs_socket); |
| 118 | |
| 119 | _debug("dework"); |
| 120 | destroy_workqueue(afs_async_calls); |
| 121 | _leave(""); |
| 122 | } |
| 123 | |
| 124 | /* |
| 125 | * allocate a call with flat request and reply buffers |
| 126 | */ |
| 127 | struct afs_call *afs_alloc_flat_call(const struct afs_call_type *type, |
| 128 | size_t request_size, size_t reply_size) |
| 129 | { |
| 130 | struct afs_call *call; |
| 131 | |
| 132 | call = kzalloc(sizeof(*call), GFP_NOFS); |
| 133 | if (!call) |
| 134 | goto nomem_call; |
| 135 | |
| 136 | if (request_size) { |
| 137 | call->request = kmalloc(request_size, GFP_NOFS); |
| 138 | if (!call->request) |
| 139 | goto nomem_request; |
| 140 | } |
| 141 | |
| 142 | if (reply_size) { |
| 143 | call->buffer = kmalloc(reply_size, GFP_NOFS); |
| 144 | if (!call->buffer) |
| 145 | goto nomem_buffer; |
| 146 | } |
| 147 | |
| 148 | call->type = type; |
| 149 | call->request_size = request_size; |
| 150 | call->reply_max = reply_size; |
| 151 | |
| 152 | init_waitqueue_head(&call->waitq); |
| 153 | skb_queue_head_init(&call->rx_queue); |
| 154 | return call; |
| 155 | |
| 156 | nomem_buffer: |
| 157 | kfree(call->request); |
| 158 | nomem_request: |
| 159 | kfree(call); |
| 160 | nomem_call: |
| 161 | return NULL; |
| 162 | } |
| 163 | |
| 164 | /* |
| 165 | * clean up a call with flat buffer |
| 166 | */ |
| 167 | void afs_flat_call_destructor(struct afs_call *call) |
| 168 | { |
| 169 | _enter(""); |
| 170 | |
| 171 | kfree(call->request); |
| 172 | call->request = NULL; |
| 173 | kfree(call->buffer); |
| 174 | call->buffer = NULL; |
| 175 | } |
| 176 | |
| 177 | /* |
| 178 | * initiate a call |
| 179 | */ |
| 180 | int afs_make_call(struct in_addr *addr, struct afs_call *call, gfp_t gfp, |
| 181 | const struct afs_wait_mode *wait_mode) |
| 182 | { |
| 183 | struct sockaddr_rxrpc srx; |
| 184 | struct rxrpc_call *rxcall; |
| 185 | struct msghdr msg; |
| 186 | struct kvec iov[1]; |
| 187 | int ret; |
| 188 | |
| 189 | _enter("%x,{%d},", addr->s_addr, ntohs(call->port)); |
| 190 | |
| 191 | call->wait_mode = wait_mode; |
| 192 | INIT_WORK(&call->async_work, afs_process_async_call); |
| 193 | |
| 194 | memset(&srx, 0, sizeof(srx)); |
| 195 | srx.srx_family = AF_RXRPC; |
| 196 | srx.srx_service = call->service_id; |
| 197 | srx.transport_type = SOCK_DGRAM; |
| 198 | srx.transport_len = sizeof(srx.transport.sin); |
| 199 | srx.transport.sin.sin_family = AF_INET; |
| 200 | srx.transport.sin.sin_port = call->port; |
| 201 | memcpy(&srx.transport.sin.sin_addr, addr, 4); |
| 202 | |
| 203 | /* create a call */ |
| 204 | rxcall = rxrpc_kernel_begin_call(afs_socket, &srx, call->key, |
| 205 | (unsigned long) call, gfp); |
| 206 | if (IS_ERR(rxcall)) { |
| 207 | ret = PTR_ERR(rxcall); |
| 208 | goto error_kill_call; |
| 209 | } |
| 210 | |
| 211 | call->rxcall = rxcall; |
| 212 | |
| 213 | /* send the request */ |
| 214 | iov[0].iov_base = call->request; |
| 215 | iov[0].iov_len = call->request_size; |
| 216 | |
| 217 | msg.msg_name = NULL; |
| 218 | msg.msg_namelen = 0; |
| 219 | msg.msg_iov = (struct iovec *) iov; |
| 220 | msg.msg_iovlen = 1; |
| 221 | msg.msg_control = NULL; |
| 222 | msg.msg_controllen = 0; |
| 223 | msg.msg_flags = 0; |
| 224 | |
| 225 | /* have to change the state *before* sending the last packet as RxRPC |
| 226 | * might give us the reply before it returns from sending the |
| 227 | * request */ |
| 228 | call->state = AFS_CALL_AWAIT_REPLY; |
| 229 | ret = rxrpc_kernel_send_data(rxcall, &msg, call->request_size); |
| 230 | if (ret < 0) |
| 231 | goto error_do_abort; |
| 232 | |
| 233 | /* at this point, an async call may no longer exist as it may have |
| 234 | * already completed */ |
| 235 | return wait_mode->wait(call); |
| 236 | |
| 237 | error_do_abort: |
| 238 | rxrpc_kernel_abort_call(rxcall, RX_USER_ABORT); |
| 239 | rxrpc_kernel_end_call(rxcall); |
| 240 | error_kill_call: |
| 241 | call->type->destructor(call); |
| 242 | ASSERT(skb_queue_empty(&call->rx_queue)); |
| 243 | kfree(call); |
| 244 | _leave(" = %d", ret); |
| 245 | return ret; |
| 246 | } |
| 247 | |
| 248 | /* |
| 249 | * handles intercepted messages that were arriving in the socket's Rx queue |
| 250 | * - called with the socket receive queue lock held to ensure message ordering |
| 251 | * - called with softirqs disabled |
| 252 | */ |
| 253 | static void afs_rx_interceptor(struct sock *sk, unsigned long user_call_ID, |
| 254 | struct sk_buff *skb) |
| 255 | { |
| 256 | struct afs_call *call = (struct afs_call *) user_call_ID; |
| 257 | |
| 258 | _enter("%p,,%u", call, skb->mark); |
| 259 | |
| 260 | ASSERTCMP(sk, ==, afs_socket->sk); |
| 261 | |
| 262 | if (!call) { |
| 263 | /* its an incoming call for our callback service */ |
| 264 | __skb_queue_tail(&afs_incoming_calls, skb); |
| 265 | schedule_work(&afs_collect_incoming_call_work); |
| 266 | } else { |
| 267 | /* route the messages directly to the appropriate call */ |
| 268 | __skb_queue_tail(&call->rx_queue, skb); |
| 269 | call->wait_mode->rx_wakeup(call); |
| 270 | } |
| 271 | |
| 272 | _leave(""); |
| 273 | } |
| 274 | |
| 275 | /* |
| 276 | * deliver messages to a call |
| 277 | */ |
| 278 | static void afs_deliver_to_call(struct afs_call *call) |
| 279 | { |
| 280 | struct sk_buff *skb; |
| 281 | bool last; |
| 282 | u32 abort_code; |
| 283 | int ret; |
| 284 | |
| 285 | _enter(""); |
| 286 | |
| 287 | while ((call->state == AFS_CALL_AWAIT_REPLY || |
| 288 | call->state == AFS_CALL_AWAIT_OP_ID || |
| 289 | call->state == AFS_CALL_AWAIT_REQUEST || |
| 290 | call->state == AFS_CALL_AWAIT_ACK) && |
| 291 | (skb = skb_dequeue(&call->rx_queue))) { |
| 292 | switch (skb->mark) { |
| 293 | case RXRPC_SKB_MARK_DATA: |
| 294 | _debug("Rcv DATA"); |
| 295 | last = rxrpc_kernel_is_data_last(skb); |
| 296 | ret = call->type->deliver(call, skb, last); |
| 297 | switch (ret) { |
| 298 | case 0: |
| 299 | if (last && |
| 300 | call->state == AFS_CALL_AWAIT_REPLY) |
| 301 | call->state = AFS_CALL_COMPLETE; |
| 302 | break; |
| 303 | case -ENOTCONN: |
| 304 | abort_code = RX_CALL_DEAD; |
| 305 | goto do_abort; |
| 306 | case -ENOTSUPP: |
| 307 | abort_code = RX_INVALID_OPERATION; |
| 308 | goto do_abort; |
| 309 | default: |
| 310 | abort_code = RXGEN_CC_UNMARSHAL; |
| 311 | if (call->state != AFS_CALL_AWAIT_REPLY) |
| 312 | abort_code = RXGEN_SS_UNMARSHAL; |
| 313 | do_abort: |
| 314 | rxrpc_kernel_abort_call(call->rxcall, |
| 315 | abort_code); |
| 316 | call->error = ret; |
| 317 | call->state = AFS_CALL_ERROR; |
| 318 | break; |
| 319 | } |
| 320 | rxrpc_kernel_data_delivered(skb); |
| 321 | skb = NULL; |
| 322 | break; |
| 323 | case RXRPC_SKB_MARK_FINAL_ACK: |
| 324 | _debug("Rcv ACK"); |
| 325 | call->state = AFS_CALL_COMPLETE; |
| 326 | break; |
| 327 | case RXRPC_SKB_MARK_BUSY: |
| 328 | _debug("Rcv BUSY"); |
| 329 | call->error = -EBUSY; |
| 330 | call->state = AFS_CALL_BUSY; |
| 331 | break; |
| 332 | case RXRPC_SKB_MARK_REMOTE_ABORT: |
| 333 | abort_code = rxrpc_kernel_get_abort_code(skb); |
| 334 | call->error = call->type->abort_to_error(abort_code); |
| 335 | call->state = AFS_CALL_ABORTED; |
| 336 | _debug("Rcv ABORT %u -> %d", abort_code, call->error); |
| 337 | break; |
| 338 | case RXRPC_SKB_MARK_NET_ERROR: |
| 339 | call->error = -rxrpc_kernel_get_error_number(skb); |
| 340 | call->state = AFS_CALL_ERROR; |
| 341 | _debug("Rcv NET ERROR %d", call->error); |
| 342 | break; |
| 343 | case RXRPC_SKB_MARK_LOCAL_ERROR: |
| 344 | call->error = -rxrpc_kernel_get_error_number(skb); |
| 345 | call->state = AFS_CALL_ERROR; |
| 346 | _debug("Rcv LOCAL ERROR %d", call->error); |
| 347 | break; |
| 348 | default: |
| 349 | BUG(); |
| 350 | break; |
| 351 | } |
| 352 | |
| 353 | rxrpc_kernel_free_skb(skb); |
| 354 | } |
| 355 | |
| 356 | /* make sure the queue is empty if the call is done with (we might have |
| 357 | * aborted the call early because of an unmarshalling error) */ |
| 358 | if (call->state >= AFS_CALL_COMPLETE) { |
| 359 | while ((skb = skb_dequeue(&call->rx_queue))) |
| 360 | rxrpc_kernel_free_skb(skb); |
| 361 | if (call->incoming) { |
| 362 | rxrpc_kernel_end_call(call->rxcall); |
| 363 | call->type->destructor(call); |
| 364 | ASSERT(skb_queue_empty(&call->rx_queue)); |
| 365 | kfree(call); |
| 366 | } |
| 367 | } |
| 368 | |
| 369 | _leave(""); |
| 370 | } |
| 371 | |
| 372 | /* |
| 373 | * wait synchronously for a call to complete |
| 374 | */ |
| 375 | static int afs_wait_for_call_to_complete(struct afs_call *call) |
| 376 | { |
| 377 | struct sk_buff *skb; |
| 378 | int ret; |
| 379 | |
| 380 | DECLARE_WAITQUEUE(myself, current); |
| 381 | |
| 382 | _enter(""); |
| 383 | |
| 384 | add_wait_queue(&call->waitq, &myself); |
| 385 | for (;;) { |
| 386 | set_current_state(TASK_INTERRUPTIBLE); |
| 387 | |
| 388 | /* deliver any messages that are in the queue */ |
| 389 | if (!skb_queue_empty(&call->rx_queue)) { |
| 390 | __set_current_state(TASK_RUNNING); |
| 391 | afs_deliver_to_call(call); |
| 392 | continue; |
| 393 | } |
| 394 | |
| 395 | ret = call->error; |
| 396 | if (call->state >= AFS_CALL_COMPLETE) |
| 397 | break; |
| 398 | ret = -EINTR; |
| 399 | if (signal_pending(current)) |
| 400 | break; |
| 401 | schedule(); |
| 402 | } |
| 403 | |
| 404 | remove_wait_queue(&call->waitq, &myself); |
| 405 | __set_current_state(TASK_RUNNING); |
| 406 | |
| 407 | /* kill the call */ |
| 408 | if (call->state < AFS_CALL_COMPLETE) { |
| 409 | _debug("call incomplete"); |
| 410 | rxrpc_kernel_abort_call(call->rxcall, RX_CALL_DEAD); |
| 411 | while ((skb = skb_dequeue(&call->rx_queue))) |
| 412 | rxrpc_kernel_free_skb(skb); |
| 413 | } |
| 414 | |
| 415 | _debug("call complete"); |
| 416 | rxrpc_kernel_end_call(call->rxcall); |
| 417 | call->type->destructor(call); |
| 418 | ASSERT(skb_queue_empty(&call->rx_queue)); |
| 419 | kfree(call); |
| 420 | _leave(" = %d", ret); |
| 421 | return ret; |
| 422 | } |
| 423 | |
| 424 | /* |
| 425 | * wake up a waiting call |
| 426 | */ |
| 427 | static void afs_wake_up_call_waiter(struct afs_call *call) |
| 428 | { |
| 429 | wake_up(&call->waitq); |
| 430 | } |
| 431 | |
| 432 | /* |
| 433 | * wake up an asynchronous call |
| 434 | */ |
| 435 | static void afs_wake_up_async_call(struct afs_call *call) |
| 436 | { |
| 437 | _enter(""); |
| 438 | queue_work(afs_async_calls, &call->async_work); |
| 439 | } |
| 440 | |
| 441 | /* |
| 442 | * put a call into asynchronous mode |
| 443 | * - mustn't touch the call descriptor as the call my have completed by the |
| 444 | * time we get here |
| 445 | */ |
| 446 | static int afs_dont_wait_for_call_to_complete(struct afs_call *call) |
| 447 | { |
| 448 | _enter(""); |
| 449 | return -EINPROGRESS; |
| 450 | } |
| 451 | |
| 452 | /* |
| 453 | * delete an asynchronous call |
| 454 | */ |
| 455 | static void afs_delete_async_call(struct work_struct *work) |
| 456 | { |
| 457 | struct afs_call *call = |
| 458 | container_of(work, struct afs_call, async_work); |
| 459 | |
| 460 | _enter(""); |
| 461 | |
| 462 | ASSERT(skb_queue_empty(&call->rx_queue)); |
| 463 | ASSERT(!work_pending(&call->async_work)); |
| 464 | kfree(call); |
| 465 | |
| 466 | _leave(""); |
| 467 | } |
| 468 | |
| 469 | /* |
| 470 | * perform processing on an asynchronous call |
| 471 | * - on a multiple-thread workqueue this work item may try to run on several |
| 472 | * CPUs at the same time |
| 473 | */ |
| 474 | static void afs_process_async_call(struct work_struct *work) |
| 475 | { |
| 476 | struct afs_call *call = |
| 477 | container_of(work, struct afs_call, async_work); |
| 478 | |
| 479 | _enter(""); |
| 480 | |
| 481 | if (!skb_queue_empty(&call->rx_queue)) |
| 482 | afs_deliver_to_call(call); |
| 483 | |
| 484 | if (call->state >= AFS_CALL_COMPLETE && call->wait_mode) { |
| 485 | if (call->wait_mode->async_complete) |
| 486 | call->wait_mode->async_complete(call->reply, |
| 487 | call->error); |
| 488 | call->reply = NULL; |
| 489 | |
| 490 | /* kill the call */ |
| 491 | rxrpc_kernel_end_call(call->rxcall); |
| 492 | if (call->type->destructor) |
| 493 | call->type->destructor(call); |
| 494 | |
| 495 | /* we can't just delete the call because the work item may be |
| 496 | * queued */ |
| 497 | PREPARE_WORK(&call->async_work, afs_delete_async_call); |
| 498 | queue_work(afs_async_calls, &call->async_work); |
| 499 | } |
| 500 | |
| 501 | _leave(""); |
| 502 | } |
| 503 | |
| 504 | /* |
| 505 | * empty a socket buffer into a flat reply buffer |
| 506 | */ |
| 507 | void afs_transfer_reply(struct afs_call *call, struct sk_buff *skb) |
| 508 | { |
| 509 | size_t len = skb->len; |
| 510 | |
| 511 | if (skb_copy_bits(skb, 0, call->buffer + call->reply_size, len) < 0) |
| 512 | BUG(); |
| 513 | call->reply_size += len; |
| 514 | } |
| 515 | |
| 516 | /* |
| 517 | * accept the backlog of incoming calls |
| 518 | */ |
| 519 | static void afs_collect_incoming_call(struct work_struct *work) |
| 520 | { |
| 521 | struct rxrpc_call *rxcall; |
| 522 | struct afs_call *call = NULL; |
| 523 | struct sk_buff *skb; |
| 524 | |
| 525 | while ((skb = skb_dequeue(&afs_incoming_calls))) { |
| 526 | _debug("new call"); |
| 527 | |
| 528 | /* don't need the notification */ |
| 529 | rxrpc_kernel_free_skb(skb); |
| 530 | |
| 531 | if (!call) { |
| 532 | call = kzalloc(sizeof(struct afs_call), GFP_KERNEL); |
| 533 | if (!call) { |
| 534 | rxrpc_kernel_reject_call(afs_socket); |
| 535 | return; |
| 536 | } |
| 537 | |
| 538 | INIT_WORK(&call->async_work, afs_process_async_call); |
| 539 | call->wait_mode = &afs_async_incoming_call; |
| 540 | call->type = &afs_RXCMxxxx; |
| 541 | init_waitqueue_head(&call->waitq); |
| 542 | skb_queue_head_init(&call->rx_queue); |
| 543 | call->state = AFS_CALL_AWAIT_OP_ID; |
| 544 | } |
| 545 | |
| 546 | rxcall = rxrpc_kernel_accept_call(afs_socket, |
| 547 | (unsigned long) call); |
| 548 | if (!IS_ERR(rxcall)) { |
| 549 | call->rxcall = rxcall; |
| 550 | call = NULL; |
| 551 | } |
| 552 | } |
| 553 | |
| 554 | kfree(call); |
| 555 | } |
| 556 | |
| 557 | /* |
| 558 | * grab the operation ID from an incoming cache manager call |
| 559 | */ |
| 560 | static int afs_deliver_cm_op_id(struct afs_call *call, struct sk_buff *skb, |
| 561 | bool last) |
| 562 | { |
| 563 | size_t len = skb->len; |
| 564 | void *oibuf = (void *) &call->operation_ID; |
| 565 | |
| 566 | _enter("{%u},{%zu},%d", call->offset, len, last); |
| 567 | |
| 568 | ASSERTCMP(call->offset, <, 4); |
| 569 | |
| 570 | /* the operation ID forms the first four bytes of the request data */ |
| 571 | len = min_t(size_t, len, 4 - call->offset); |
| 572 | if (skb_copy_bits(skb, 0, oibuf + call->offset, len) < 0) |
| 573 | BUG(); |
| 574 | if (!pskb_pull(skb, len)) |
| 575 | BUG(); |
| 576 | call->offset += len; |
| 577 | |
| 578 | if (call->offset < 4) { |
| 579 | if (last) { |
| 580 | _leave(" = -EBADMSG [op ID short]"); |
| 581 | return -EBADMSG; |
| 582 | } |
| 583 | _leave(" = 0 [incomplete]"); |
| 584 | return 0; |
| 585 | } |
| 586 | |
| 587 | call->state = AFS_CALL_AWAIT_REQUEST; |
| 588 | |
| 589 | /* ask the cache manager to route the call (it'll change the call type |
| 590 | * if successful) */ |
| 591 | if (!afs_cm_incoming_call(call)) |
| 592 | return -ENOTSUPP; |
| 593 | |
| 594 | /* pass responsibility for the remainer of this message off to the |
| 595 | * cache manager op */ |
| 596 | return call->type->deliver(call, skb, last); |
| 597 | } |
| 598 | |
| 599 | /* |
| 600 | * send an empty reply |
| 601 | */ |
| 602 | void afs_send_empty_reply(struct afs_call *call) |
| 603 | { |
| 604 | struct msghdr msg; |
| 605 | struct iovec iov[1]; |
| 606 | |
| 607 | _enter(""); |
| 608 | |
| 609 | iov[0].iov_base = NULL; |
| 610 | iov[0].iov_len = 0; |
| 611 | msg.msg_name = NULL; |
| 612 | msg.msg_namelen = 0; |
| 613 | msg.msg_iov = iov; |
| 614 | msg.msg_iovlen = 0; |
| 615 | msg.msg_control = NULL; |
| 616 | msg.msg_controllen = 0; |
| 617 | msg.msg_flags = 0; |
| 618 | |
| 619 | call->state = AFS_CALL_AWAIT_ACK; |
| 620 | switch (rxrpc_kernel_send_data(call->rxcall, &msg, 0)) { |
| 621 | case 0: |
| 622 | _leave(" [replied]"); |
| 623 | return; |
| 624 | |
| 625 | case -ENOMEM: |
| 626 | _debug("oom"); |
| 627 | rxrpc_kernel_abort_call(call->rxcall, RX_USER_ABORT); |
| 628 | default: |
| 629 | rxrpc_kernel_end_call(call->rxcall); |
| 630 | call->rxcall = NULL; |
| 631 | call->type->destructor(call); |
| 632 | ASSERT(skb_queue_empty(&call->rx_queue)); |
| 633 | kfree(call); |
| 634 | _leave(" [error]"); |
| 635 | return; |
| 636 | } |
| 637 | } |
| 638 | |
| 639 | /* |
| 640 | * extract a piece of data from the received data socket buffers |
| 641 | */ |
| 642 | int afs_extract_data(struct afs_call *call, struct sk_buff *skb, |
| 643 | bool last, void *buf, size_t count) |
| 644 | { |
| 645 | size_t len = skb->len; |
| 646 | |
| 647 | _enter("{%u},{%zu},%d,,%zu", call->offset, len, last, count); |
| 648 | |
| 649 | ASSERTCMP(call->offset, <, count); |
| 650 | |
| 651 | len = min_t(size_t, len, count - call->offset); |
| 652 | if (skb_copy_bits(skb, 0, buf + call->offset, len) < 0 || |
| 653 | !pskb_pull(skb, len)) |
| 654 | BUG(); |
| 655 | call->offset += len; |
| 656 | |
| 657 | if (call->offset < count) { |
| 658 | if (last) { |
| 659 | _leave(" = -EBADMSG [%d < %lu]", call->offset, count); |
| 660 | return -EBADMSG; |
| 661 | } |
| 662 | _leave(" = -EAGAIN"); |
| 663 | return -EAGAIN; |
| 664 | } |
| 665 | return 0; |
| 666 | } |