1 /* Maintain an RxRPC server socket to do AFS communications through
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
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.
13 #include <net/af_rxrpc.h>
14 #include <rxrpc/packet.h>
18 static struct socket *afs_socket; /* my RxRPC socket */
19 static struct workqueue_struct *afs_async_calls;
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);
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,
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,
41 /* asynchronous incoming call management */
42 static const struct afs_wait_mode afs_async_incoming_call = {
43 .rx_wakeup = afs_wake_up_async_call,
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,
52 static void afs_collect_incoming_call(struct work_struct *);
54 static struct sk_buff_head afs_incoming_calls;
55 static DECLARE_WORK(afs_collect_incoming_call_work, afs_collect_incoming_call);
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
61 int afs_open_socket(void)
63 struct sockaddr_rxrpc srx;
64 struct socket *socket;
69 skb_queue_head_init(&afs_incoming_calls);
71 afs_async_calls = create_singlethread_workqueue("kafsd");
72 if (!afs_async_calls) {
73 _leave(" = -ENOMEM [wq]");
77 ret = sock_create_kern(AF_RXRPC, SOCK_DGRAM, PF_INET, &socket);
79 destroy_workqueue(afs_async_calls);
80 _leave(" = %d [socket]", ret);
84 socket->sk->sk_allocation = GFP_NOFS;
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));
96 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx));
99 _leave(" = %d [bind]", ret);
103 rxrpc_kernel_intercept_rx_messages(socket, afs_rx_interceptor);
111 * close the RxRPC socket AFS was using
113 void afs_close_socket(void)
117 sock_release(afs_socket);
120 destroy_workqueue(afs_async_calls);
125 * allocate a call with flat request and reply buffers
127 struct afs_call *afs_alloc_flat_call(const struct afs_call_type *type,
128 size_t request_size, size_t reply_size)
130 struct afs_call *call;
132 call = kzalloc(sizeof(*call), GFP_NOFS);
137 call->request = kmalloc(request_size, GFP_NOFS);
143 call->buffer = kmalloc(reply_size, GFP_NOFS);
149 call->request_size = request_size;
150 call->reply_max = reply_size;
152 init_waitqueue_head(&call->waitq);
153 skb_queue_head_init(&call->rx_queue);
157 kfree(call->request);
165 * clean up a call with flat buffer
167 void afs_flat_call_destructor(struct afs_call *call)
171 kfree(call->request);
172 call->request = NULL;
180 int afs_make_call(struct in_addr *addr, struct afs_call *call, gfp_t gfp,
181 const struct afs_wait_mode *wait_mode)
183 struct sockaddr_rxrpc srx;
184 struct rxrpc_call *rxcall;
189 _enter("%x,{%d},", addr->s_addr, ntohs(call->port));
191 call->wait_mode = wait_mode;
192 INIT_WORK(&call->async_work, afs_process_async_call);
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);
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;
211 call->rxcall = rxcall;
213 /* send the request */
214 iov[0].iov_base = call->request;
215 iov[0].iov_len = call->request_size;
219 msg.msg_iov = (struct iovec *) iov;
221 msg.msg_control = NULL;
222 msg.msg_controllen = 0;
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
228 call->state = AFS_CALL_AWAIT_REPLY;
229 ret = rxrpc_kernel_send_data(rxcall, &msg, call->request_size);
233 /* at this point, an async call may no longer exist as it may have
234 * already completed */
235 return wait_mode->wait(call);
238 rxrpc_kernel_abort_call(rxcall, RX_USER_ABORT);
239 rxrpc_kernel_end_call(rxcall);
241 call->type->destructor(call);
242 ASSERT(skb_queue_empty(&call->rx_queue));
244 _leave(" = %d", ret);
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
253 static void afs_rx_interceptor(struct sock *sk, unsigned long user_call_ID,
256 struct afs_call *call = (struct afs_call *) user_call_ID;
258 _enter("%p,,%u", call, skb->mark);
260 ASSERTCMP(sk, ==, afs_socket->sk);
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);
267 /* route the messages directly to the appropriate call */
268 __skb_queue_tail(&call->rx_queue, skb);
269 call->wait_mode->rx_wakeup(call);
276 * deliver messages to a call
278 static void afs_deliver_to_call(struct afs_call *call)
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))) {
293 case RXRPC_SKB_MARK_DATA:
295 last = rxrpc_kernel_is_data_last(skb);
296 ret = call->type->deliver(call, skb, last);
300 call->state == AFS_CALL_AWAIT_REPLY)
301 call->state = AFS_CALL_COMPLETE;
304 abort_code = RX_CALL_DEAD;
307 abort_code = RX_INVALID_OPERATION;
310 abort_code = RXGEN_CC_UNMARSHAL;
311 if (call->state != AFS_CALL_AWAIT_REPLY)
312 abort_code = RXGEN_SS_UNMARSHAL;
314 rxrpc_kernel_abort_call(call->rxcall,
317 call->state = AFS_CALL_ERROR;
320 rxrpc_kernel_data_delivered(skb);
323 case RXRPC_SKB_MARK_FINAL_ACK:
325 call->state = AFS_CALL_COMPLETE;
327 case RXRPC_SKB_MARK_BUSY:
329 call->error = -EBUSY;
330 call->state = AFS_CALL_BUSY;
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);
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);
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);
353 rxrpc_kernel_free_skb(skb);
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));
373 * wait synchronously for a call to complete
375 static int afs_wait_for_call_to_complete(struct afs_call *call)
380 DECLARE_WAITQUEUE(myself, current);
384 add_wait_queue(&call->waitq, &myself);
386 set_current_state(TASK_INTERRUPTIBLE);
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);
396 if (call->state >= AFS_CALL_COMPLETE)
399 if (signal_pending(current))
404 remove_wait_queue(&call->waitq, &myself);
405 __set_current_state(TASK_RUNNING);
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);
415 _debug("call complete");
416 rxrpc_kernel_end_call(call->rxcall);
417 call->type->destructor(call);
418 ASSERT(skb_queue_empty(&call->rx_queue));
420 _leave(" = %d", ret);
425 * wake up a waiting call
427 static void afs_wake_up_call_waiter(struct afs_call *call)
429 wake_up(&call->waitq);
433 * wake up an asynchronous call
435 static void afs_wake_up_async_call(struct afs_call *call)
438 queue_work(afs_async_calls, &call->async_work);
442 * put a call into asynchronous mode
443 * - mustn't touch the call descriptor as the call my have completed by the
446 static int afs_dont_wait_for_call_to_complete(struct afs_call *call)
453 * delete an asynchronous call
455 static void afs_delete_async_call(struct work_struct *work)
457 struct afs_call *call =
458 container_of(work, struct afs_call, async_work);
462 ASSERT(skb_queue_empty(&call->rx_queue));
463 ASSERT(!work_pending(&call->async_work));
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
474 static void afs_process_async_call(struct work_struct *work)
476 struct afs_call *call =
477 container_of(work, struct afs_call, async_work);
481 if (!skb_queue_empty(&call->rx_queue))
482 afs_deliver_to_call(call);
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,
491 rxrpc_kernel_end_call(call->rxcall);
492 if (call->type->destructor)
493 call->type->destructor(call);
495 /* we can't just delete the call because the work item may be
497 PREPARE_WORK(&call->async_work, afs_delete_async_call);
498 queue_work(afs_async_calls, &call->async_work);
505 * empty a socket buffer into a flat reply buffer
507 void afs_transfer_reply(struct afs_call *call, struct sk_buff *skb)
509 size_t len = skb->len;
511 if (skb_copy_bits(skb, 0, call->buffer + call->reply_size, len) < 0)
513 call->reply_size += len;
517 * accept the backlog of incoming calls
519 static void afs_collect_incoming_call(struct work_struct *work)
521 struct rxrpc_call *rxcall;
522 struct afs_call *call = NULL;
525 while ((skb = skb_dequeue(&afs_incoming_calls))) {
528 /* don't need the notification */
529 rxrpc_kernel_free_skb(skb);
532 call = kzalloc(sizeof(struct afs_call), GFP_KERNEL);
534 rxrpc_kernel_reject_call(afs_socket);
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;
546 rxcall = rxrpc_kernel_accept_call(afs_socket,
547 (unsigned long) call);
548 if (!IS_ERR(rxcall)) {
549 call->rxcall = rxcall;
558 * grab the operation ID from an incoming cache manager call
560 static int afs_deliver_cm_op_id(struct afs_call *call, struct sk_buff *skb,
563 size_t len = skb->len;
564 void *oibuf = (void *) &call->operation_ID;
566 _enter("{%u},{%zu},%d", call->offset, len, last);
568 ASSERTCMP(call->offset, <, 4);
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)
574 if (!pskb_pull(skb, len))
578 if (call->offset < 4) {
580 _leave(" = -EBADMSG [op ID short]");
583 _leave(" = 0 [incomplete]");
587 call->state = AFS_CALL_AWAIT_REQUEST;
589 /* ask the cache manager to route the call (it'll change the call type
591 if (!afs_cm_incoming_call(call))
594 /* pass responsibility for the remainer of this message off to the
595 * cache manager op */
596 return call->type->deliver(call, skb, last);
600 * send an empty reply
602 void afs_send_empty_reply(struct afs_call *call)
609 iov[0].iov_base = NULL;
615 msg.msg_control = NULL;
616 msg.msg_controllen = 0;
619 call->state = AFS_CALL_AWAIT_ACK;
620 switch (rxrpc_kernel_send_data(call->rxcall, &msg, 0)) {
622 _leave(" [replied]");
627 rxrpc_kernel_abort_call(call->rxcall, RX_USER_ABORT);
629 rxrpc_kernel_end_call(call->rxcall);
631 call->type->destructor(call);
632 ASSERT(skb_queue_empty(&call->rx_queue));
640 * extract a piece of data from the received data socket buffers
642 int afs_extract_data(struct afs_call *call, struct sk_buff *skb,
643 bool last, void *buf, size_t count)
645 size_t len = skb->len;
647 _enter("{%u},{%zu},%d,,%zu", call->offset, len, last, count);
649 ASSERTCMP(call->offset, <, count);
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))
657 if (call->offset < count) {
659 _leave(" = -EBADMSG [%d < %lu]", call->offset, count);
662 _leave(" = -EAGAIN");