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
;
20 static atomic_t afs_outstanding_calls
;
21 static atomic_t afs_outstanding_skbs
;
23 static void afs_wake_up_call_waiter(struct afs_call
*);
24 static int afs_wait_for_call_to_complete(struct afs_call
*);
25 static void afs_wake_up_async_call(struct afs_call
*);
26 static int afs_dont_wait_for_call_to_complete(struct afs_call
*);
27 static void afs_process_async_call(struct work_struct
*);
28 static void afs_rx_interceptor(struct sock
*, unsigned long, struct sk_buff
*);
29 static int afs_deliver_cm_op_id(struct afs_call
*, struct sk_buff
*, bool);
31 /* synchronous call management */
32 const struct afs_wait_mode afs_sync_call
= {
33 .rx_wakeup
= afs_wake_up_call_waiter
,
34 .wait
= afs_wait_for_call_to_complete
,
37 /* asynchronous call management */
38 const struct afs_wait_mode afs_async_call
= {
39 .rx_wakeup
= afs_wake_up_async_call
,
40 .wait
= afs_dont_wait_for_call_to_complete
,
43 /* asynchronous incoming call management */
44 static const struct afs_wait_mode afs_async_incoming_call
= {
45 .rx_wakeup
= afs_wake_up_async_call
,
48 /* asynchronous incoming call initial processing */
49 static const struct afs_call_type afs_RXCMxxxx
= {
51 .deliver
= afs_deliver_cm_op_id
,
52 .abort_to_error
= afs_abort_to_error
,
55 static void afs_collect_incoming_call(struct work_struct
*);
57 static struct sk_buff_head afs_incoming_calls
;
58 static DECLARE_WORK(afs_collect_incoming_call_work
, afs_collect_incoming_call
);
61 * open an RxRPC socket and bind it to be a server for callback notifications
62 * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT
64 int afs_open_socket(void)
66 struct sockaddr_rxrpc srx
;
67 struct socket
*socket
;
72 skb_queue_head_init(&afs_incoming_calls
);
74 afs_async_calls
= create_singlethread_workqueue("kafsd");
75 if (!afs_async_calls
) {
76 _leave(" = -ENOMEM [wq]");
80 ret
= sock_create_kern(AF_RXRPC
, SOCK_DGRAM
, PF_INET
, &socket
);
82 destroy_workqueue(afs_async_calls
);
83 _leave(" = %d [socket]", ret
);
87 socket
->sk
->sk_allocation
= GFP_NOFS
;
89 /* bind the callback manager's address to make this a server socket */
90 srx
.srx_family
= AF_RXRPC
;
91 srx
.srx_service
= CM_SERVICE
;
92 srx
.transport_type
= SOCK_DGRAM
;
93 srx
.transport_len
= sizeof(srx
.transport
.sin
);
94 srx
.transport
.sin
.sin_family
= AF_INET
;
95 srx
.transport
.sin
.sin_port
= htons(AFS_CM_PORT
);
96 memset(&srx
.transport
.sin
.sin_addr
, 0,
97 sizeof(srx
.transport
.sin
.sin_addr
));
99 ret
= kernel_bind(socket
, (struct sockaddr
*) &srx
, sizeof(srx
));
101 sock_release(socket
);
102 _leave(" = %d [bind]", ret
);
106 rxrpc_kernel_intercept_rx_messages(socket
, afs_rx_interceptor
);
114 * close the RxRPC socket AFS was using
116 void afs_close_socket(void)
120 sock_release(afs_socket
);
123 destroy_workqueue(afs_async_calls
);
125 ASSERTCMP(atomic_read(&afs_outstanding_skbs
), ==, 0);
126 ASSERTCMP(atomic_read(&afs_outstanding_calls
), ==, 0);
131 * note that the data in a socket buffer is now delivered and that the buffer
134 static void afs_data_delivered(struct sk_buff
*skb
)
137 _debug("DLVR NULL [%d]", atomic_read(&afs_outstanding_skbs
));
140 _debug("DLVR %p{%u} [%d]",
141 skb
, skb
->mark
, atomic_read(&afs_outstanding_skbs
));
142 if (atomic_dec_return(&afs_outstanding_skbs
) == -1)
144 rxrpc_kernel_data_delivered(skb
);
149 * free a socket buffer
151 static void afs_free_skb(struct sk_buff
*skb
)
154 _debug("FREE NULL [%d]", atomic_read(&afs_outstanding_skbs
));
157 _debug("FREE %p{%u} [%d]",
158 skb
, skb
->mark
, atomic_read(&afs_outstanding_skbs
));
159 if (atomic_dec_return(&afs_outstanding_skbs
) == -1)
161 rxrpc_kernel_free_skb(skb
);
168 static void afs_free_call(struct afs_call
*call
)
170 _debug("DONE %p{%s} [%d]",
171 call
, call
->type
->name
, atomic_read(&afs_outstanding_calls
));
172 if (atomic_dec_return(&afs_outstanding_calls
) == -1)
175 ASSERTCMP(call
->rxcall
, ==, NULL
);
176 ASSERT(!work_pending(&call
->async_work
));
177 ASSERT(skb_queue_empty(&call
->rx_queue
));
178 ASSERT(call
->type
->name
!= NULL
);
180 kfree(call
->request
);
185 * allocate a call with flat request and reply buffers
187 struct afs_call
*afs_alloc_flat_call(const struct afs_call_type
*type
,
188 size_t request_size
, size_t reply_size
)
190 struct afs_call
*call
;
192 call
= kzalloc(sizeof(*call
), GFP_NOFS
);
196 _debug("CALL %p{%s} [%d]",
197 call
, type
->name
, atomic_read(&afs_outstanding_calls
));
198 atomic_inc(&afs_outstanding_calls
);
201 call
->request_size
= request_size
;
202 call
->reply_max
= reply_size
;
205 call
->request
= kmalloc(request_size
, GFP_NOFS
);
211 call
->buffer
= kmalloc(reply_size
, GFP_NOFS
);
216 init_waitqueue_head(&call
->waitq
);
217 skb_queue_head_init(&call
->rx_queue
);
227 * clean up a call with flat buffer
229 void afs_flat_call_destructor(struct afs_call
*call
)
233 kfree(call
->request
);
234 call
->request
= NULL
;
242 int afs_make_call(struct in_addr
*addr
, struct afs_call
*call
, gfp_t gfp
,
243 const struct afs_wait_mode
*wait_mode
)
245 struct sockaddr_rxrpc srx
;
246 struct rxrpc_call
*rxcall
;
251 _enter("%x,{%d},", addr
->s_addr
, ntohs(call
->port
));
253 ASSERT(call
->type
!= NULL
);
254 ASSERT(call
->type
->name
!= NULL
);
256 _debug("MAKE %p{%s} [%d]",
257 call
, call
->type
->name
, atomic_read(&afs_outstanding_calls
));
259 call
->wait_mode
= wait_mode
;
260 INIT_WORK(&call
->async_work
, afs_process_async_call
);
262 memset(&srx
, 0, sizeof(srx
));
263 srx
.srx_family
= AF_RXRPC
;
264 srx
.srx_service
= call
->service_id
;
265 srx
.transport_type
= SOCK_DGRAM
;
266 srx
.transport_len
= sizeof(srx
.transport
.sin
);
267 srx
.transport
.sin
.sin_family
= AF_INET
;
268 srx
.transport
.sin
.sin_port
= call
->port
;
269 memcpy(&srx
.transport
.sin
.sin_addr
, addr
, 4);
272 rxcall
= rxrpc_kernel_begin_call(afs_socket
, &srx
, call
->key
,
273 (unsigned long) call
, gfp
);
275 if (IS_ERR(rxcall
)) {
276 ret
= PTR_ERR(rxcall
);
277 goto error_kill_call
;
280 call
->rxcall
= rxcall
;
282 /* send the request */
283 iov
[0].iov_base
= call
->request
;
284 iov
[0].iov_len
= call
->request_size
;
288 msg
.msg_iov
= (struct iovec
*) iov
;
290 msg
.msg_control
= NULL
;
291 msg
.msg_controllen
= 0;
294 /* have to change the state *before* sending the last packet as RxRPC
295 * might give us the reply before it returns from sending the
297 call
->state
= AFS_CALL_AWAIT_REPLY
;
298 ret
= rxrpc_kernel_send_data(rxcall
, &msg
, call
->request_size
);
302 /* at this point, an async call may no longer exist as it may have
303 * already completed */
304 return wait_mode
->wait(call
);
307 rxrpc_kernel_abort_call(rxcall
, RX_USER_ABORT
);
308 rxrpc_kernel_end_call(rxcall
);
311 call
->type
->destructor(call
);
313 _leave(" = %d", ret
);
318 * handles intercepted messages that were arriving in the socket's Rx queue
319 * - called with the socket receive queue lock held to ensure message ordering
320 * - called with softirqs disabled
322 static void afs_rx_interceptor(struct sock
*sk
, unsigned long user_call_ID
,
325 struct afs_call
*call
= (struct afs_call
*) user_call_ID
;
327 _enter("%p,,%u", call
, skb
->mark
);
329 _debug("ICPT %p{%u} [%d]",
330 skb
, skb
->mark
, atomic_read(&afs_outstanding_skbs
));
332 ASSERTCMP(sk
, ==, afs_socket
->sk
);
333 atomic_inc(&afs_outstanding_skbs
);
336 /* its an incoming call for our callback service */
337 skb_queue_tail(&afs_incoming_calls
, skb
);
338 schedule_work(&afs_collect_incoming_call_work
);
340 /* route the messages directly to the appropriate call */
341 skb_queue_tail(&call
->rx_queue
, skb
);
342 call
->wait_mode
->rx_wakeup(call
);
349 * deliver messages to a call
351 static void afs_deliver_to_call(struct afs_call
*call
)
360 while ((call
->state
== AFS_CALL_AWAIT_REPLY
||
361 call
->state
== AFS_CALL_AWAIT_OP_ID
||
362 call
->state
== AFS_CALL_AWAIT_REQUEST
||
363 call
->state
== AFS_CALL_AWAIT_ACK
) &&
364 (skb
= skb_dequeue(&call
->rx_queue
))) {
366 case RXRPC_SKB_MARK_DATA
:
368 last
= rxrpc_kernel_is_data_last(skb
);
369 ret
= call
->type
->deliver(call
, skb
, last
);
373 call
->state
== AFS_CALL_AWAIT_REPLY
)
374 call
->state
= AFS_CALL_COMPLETE
;
377 abort_code
= RX_CALL_DEAD
;
380 abort_code
= RX_INVALID_OPERATION
;
383 abort_code
= RXGEN_CC_UNMARSHAL
;
384 if (call
->state
!= AFS_CALL_AWAIT_REPLY
)
385 abort_code
= RXGEN_SS_UNMARSHAL
;
387 rxrpc_kernel_abort_call(call
->rxcall
,
390 call
->state
= AFS_CALL_ERROR
;
393 afs_data_delivered(skb
);
396 case RXRPC_SKB_MARK_FINAL_ACK
:
398 call
->state
= AFS_CALL_COMPLETE
;
400 case RXRPC_SKB_MARK_BUSY
:
402 call
->error
= -EBUSY
;
403 call
->state
= AFS_CALL_BUSY
;
405 case RXRPC_SKB_MARK_REMOTE_ABORT
:
406 abort_code
= rxrpc_kernel_get_abort_code(skb
);
407 call
->error
= call
->type
->abort_to_error(abort_code
);
408 call
->state
= AFS_CALL_ABORTED
;
409 _debug("Rcv ABORT %u -> %d", abort_code
, call
->error
);
411 case RXRPC_SKB_MARK_NET_ERROR
:
412 call
->error
= -rxrpc_kernel_get_error_number(skb
);
413 call
->state
= AFS_CALL_ERROR
;
414 _debug("Rcv NET ERROR %d", call
->error
);
416 case RXRPC_SKB_MARK_LOCAL_ERROR
:
417 call
->error
= -rxrpc_kernel_get_error_number(skb
);
418 call
->state
= AFS_CALL_ERROR
;
419 _debug("Rcv LOCAL ERROR %d", call
->error
);
429 /* make sure the queue is empty if the call is done with (we might have
430 * aborted the call early because of an unmarshalling error) */
431 if (call
->state
>= AFS_CALL_COMPLETE
) {
432 while ((skb
= skb_dequeue(&call
->rx_queue
)))
434 if (call
->incoming
) {
435 rxrpc_kernel_end_call(call
->rxcall
);
437 call
->type
->destructor(call
);
446 * wait synchronously for a call to complete
448 static int afs_wait_for_call_to_complete(struct afs_call
*call
)
453 DECLARE_WAITQUEUE(myself
, current
);
457 add_wait_queue(&call
->waitq
, &myself
);
459 set_current_state(TASK_INTERRUPTIBLE
);
461 /* deliver any messages that are in the queue */
462 if (!skb_queue_empty(&call
->rx_queue
)) {
463 __set_current_state(TASK_RUNNING
);
464 afs_deliver_to_call(call
);
469 if (call
->state
>= AFS_CALL_COMPLETE
)
472 if (signal_pending(current
))
477 remove_wait_queue(&call
->waitq
, &myself
);
478 __set_current_state(TASK_RUNNING
);
481 if (call
->state
< AFS_CALL_COMPLETE
) {
482 _debug("call incomplete");
483 rxrpc_kernel_abort_call(call
->rxcall
, RX_CALL_DEAD
);
484 while ((skb
= skb_dequeue(&call
->rx_queue
)))
488 _debug("call complete");
489 rxrpc_kernel_end_call(call
->rxcall
);
491 call
->type
->destructor(call
);
493 _leave(" = %d", ret
);
498 * wake up a waiting call
500 static void afs_wake_up_call_waiter(struct afs_call
*call
)
502 wake_up(&call
->waitq
);
506 * wake up an asynchronous call
508 static void afs_wake_up_async_call(struct afs_call
*call
)
511 queue_work(afs_async_calls
, &call
->async_work
);
515 * put a call into asynchronous mode
516 * - mustn't touch the call descriptor as the call my have completed by the
519 static int afs_dont_wait_for_call_to_complete(struct afs_call
*call
)
526 * delete an asynchronous call
528 static void afs_delete_async_call(struct work_struct
*work
)
530 struct afs_call
*call
=
531 container_of(work
, struct afs_call
, async_work
);
541 * perform processing on an asynchronous call
542 * - on a multiple-thread workqueue this work item may try to run on several
543 * CPUs at the same time
545 static void afs_process_async_call(struct work_struct
*work
)
547 struct afs_call
*call
=
548 container_of(work
, struct afs_call
, async_work
);
552 if (!skb_queue_empty(&call
->rx_queue
))
553 afs_deliver_to_call(call
);
555 if (call
->state
>= AFS_CALL_COMPLETE
&& call
->wait_mode
) {
556 if (call
->wait_mode
->async_complete
)
557 call
->wait_mode
->async_complete(call
->reply
,
562 rxrpc_kernel_end_call(call
->rxcall
);
564 if (call
->type
->destructor
)
565 call
->type
->destructor(call
);
567 /* we can't just delete the call because the work item may be
569 PREPARE_WORK(&call
->async_work
, afs_delete_async_call
);
570 queue_work(afs_async_calls
, &call
->async_work
);
577 * empty a socket buffer into a flat reply buffer
579 void afs_transfer_reply(struct afs_call
*call
, struct sk_buff
*skb
)
581 size_t len
= skb
->len
;
583 if (skb_copy_bits(skb
, 0, call
->buffer
+ call
->reply_size
, len
) < 0)
585 call
->reply_size
+= len
;
589 * accept the backlog of incoming calls
591 static void afs_collect_incoming_call(struct work_struct
*work
)
593 struct rxrpc_call
*rxcall
;
594 struct afs_call
*call
= NULL
;
597 while ((skb
= skb_dequeue(&afs_incoming_calls
))) {
600 /* don't need the notification */
604 call
= kzalloc(sizeof(struct afs_call
), GFP_KERNEL
);
606 rxrpc_kernel_reject_call(afs_socket
);
610 INIT_WORK(&call
->async_work
, afs_process_async_call
);
611 call
->wait_mode
= &afs_async_incoming_call
;
612 call
->type
= &afs_RXCMxxxx
;
613 init_waitqueue_head(&call
->waitq
);
614 skb_queue_head_init(&call
->rx_queue
);
615 call
->state
= AFS_CALL_AWAIT_OP_ID
;
617 _debug("CALL %p{%s} [%d]",
618 call
, call
->type
->name
,
619 atomic_read(&afs_outstanding_calls
));
620 atomic_inc(&afs_outstanding_calls
);
623 rxcall
= rxrpc_kernel_accept_call(afs_socket
,
624 (unsigned long) call
);
625 if (!IS_ERR(rxcall
)) {
626 call
->rxcall
= rxcall
;
636 * grab the operation ID from an incoming cache manager call
638 static int afs_deliver_cm_op_id(struct afs_call
*call
, struct sk_buff
*skb
,
641 size_t len
= skb
->len
;
642 void *oibuf
= (void *) &call
->operation_ID
;
644 _enter("{%u},{%zu},%d", call
->offset
, len
, last
);
646 ASSERTCMP(call
->offset
, <, 4);
648 /* the operation ID forms the first four bytes of the request data */
649 len
= min_t(size_t, len
, 4 - call
->offset
);
650 if (skb_copy_bits(skb
, 0, oibuf
+ call
->offset
, len
) < 0)
652 if (!pskb_pull(skb
, len
))
656 if (call
->offset
< 4) {
658 _leave(" = -EBADMSG [op ID short]");
661 _leave(" = 0 [incomplete]");
665 call
->state
= AFS_CALL_AWAIT_REQUEST
;
667 /* ask the cache manager to route the call (it'll change the call type
669 if (!afs_cm_incoming_call(call
))
672 /* pass responsibility for the remainer of this message off to the
673 * cache manager op */
674 return call
->type
->deliver(call
, skb
, last
);
678 * send an empty reply
680 void afs_send_empty_reply(struct afs_call
*call
)
687 iov
[0].iov_base
= NULL
;
693 msg
.msg_control
= NULL
;
694 msg
.msg_controllen
= 0;
697 call
->state
= AFS_CALL_AWAIT_ACK
;
698 switch (rxrpc_kernel_send_data(call
->rxcall
, &msg
, 0)) {
700 _leave(" [replied]");
705 rxrpc_kernel_abort_call(call
->rxcall
, RX_USER_ABORT
);
707 rxrpc_kernel_end_call(call
->rxcall
);
709 call
->type
->destructor(call
);
717 * send a simple reply
719 void afs_send_simple_reply(struct afs_call
*call
, const void *buf
, size_t len
)
726 iov
[0].iov_base
= (void *) buf
;
727 iov
[0].iov_len
= len
;
732 msg
.msg_control
= NULL
;
733 msg
.msg_controllen
= 0;
736 call
->state
= AFS_CALL_AWAIT_ACK
;
737 switch (rxrpc_kernel_send_data(call
->rxcall
, &msg
, len
)) {
739 _leave(" [replied]");
744 rxrpc_kernel_abort_call(call
->rxcall
, RX_USER_ABORT
);
746 rxrpc_kernel_end_call(call
->rxcall
);
748 call
->type
->destructor(call
);
756 * extract a piece of data from the received data socket buffers
758 int afs_extract_data(struct afs_call
*call
, struct sk_buff
*skb
,
759 bool last
, void *buf
, size_t count
)
761 size_t len
= skb
->len
;
763 _enter("{%u},{%zu},%d,,%zu", call
->offset
, len
, last
, count
);
765 ASSERTCMP(call
->offset
, <, count
);
767 len
= min_t(size_t, len
, count
- call
->offset
);
768 if (skb_copy_bits(skb
, 0, buf
+ call
->offset
, len
) < 0 ||
769 !pskb_pull(skb
, len
))
773 if (call
->offset
< count
) {
775 _leave(" = -EBADMSG [%d < %zu]", call
->offset
, count
);
778 _leave(" = -EAGAIN");