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.
12 #include <linux/slab.h>
14 #include <net/af_rxrpc.h>
15 #include <rxrpc/packet.h>
19 struct socket
*afs_socket
; /* my RxRPC socket */
20 static struct workqueue_struct
*afs_async_calls
;
21 static struct afs_call
*afs_spare_incoming_call
;
22 static atomic_t afs_outstanding_calls
;
24 static void afs_free_call(struct afs_call
*);
25 static void afs_wake_up_call_waiter(struct sock
*, struct rxrpc_call
*, unsigned long);
26 static int afs_wait_for_call_to_complete(struct afs_call
*);
27 static void afs_wake_up_async_call(struct sock
*, struct rxrpc_call
*, unsigned long);
28 static int afs_dont_wait_for_call_to_complete(struct afs_call
*);
29 static void afs_process_async_call(struct work_struct
*);
30 static void afs_rx_new_call(struct sock
*, struct rxrpc_call
*, unsigned long);
31 static void afs_rx_discard_new_call(struct rxrpc_call
*, unsigned long);
32 static int afs_deliver_cm_op_id(struct afs_call
*);
34 /* synchronous call management */
35 const struct afs_wait_mode afs_sync_call
= {
36 .notify_rx
= afs_wake_up_call_waiter
,
37 .wait
= afs_wait_for_call_to_complete
,
40 /* asynchronous call management */
41 const struct afs_wait_mode afs_async_call
= {
42 .notify_rx
= afs_wake_up_async_call
,
43 .wait
= afs_dont_wait_for_call_to_complete
,
46 /* asynchronous incoming call management */
47 static const struct afs_wait_mode afs_async_incoming_call
= {
48 .notify_rx
= afs_wake_up_async_call
,
51 /* asynchronous incoming call initial processing */
52 static const struct afs_call_type afs_RXCMxxxx
= {
54 .deliver
= afs_deliver_cm_op_id
,
55 .abort_to_error
= afs_abort_to_error
,
58 static void afs_charge_preallocation(struct work_struct
*);
60 static DECLARE_WORK(afs_charge_preallocation_work
, afs_charge_preallocation
);
62 static int afs_wait_atomic_t(atomic_t
*p
)
69 * open an RxRPC socket and bind it to be a server for callback notifications
70 * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT
72 int afs_open_socket(void)
74 struct sockaddr_rxrpc srx
;
75 struct socket
*socket
;
81 afs_async_calls
= alloc_workqueue("kafsd", WQ_MEM_RECLAIM
, 0);
85 ret
= sock_create_kern(&init_net
, AF_RXRPC
, SOCK_DGRAM
, PF_INET
, &socket
);
89 socket
->sk
->sk_allocation
= GFP_NOFS
;
91 /* bind the callback manager's address to make this a server socket */
92 srx
.srx_family
= AF_RXRPC
;
93 srx
.srx_service
= CM_SERVICE
;
94 srx
.transport_type
= SOCK_DGRAM
;
95 srx
.transport_len
= sizeof(srx
.transport
.sin
);
96 srx
.transport
.sin
.sin_family
= AF_INET
;
97 srx
.transport
.sin
.sin_port
= htons(AFS_CM_PORT
);
98 memset(&srx
.transport
.sin
.sin_addr
, 0,
99 sizeof(srx
.transport
.sin
.sin_addr
));
101 ret
= kernel_bind(socket
, (struct sockaddr
*) &srx
, sizeof(srx
));
105 rxrpc_kernel_new_call_notification(socket
, afs_rx_new_call
,
106 afs_rx_discard_new_call
);
108 ret
= kernel_listen(socket
, INT_MAX
);
113 afs_charge_preallocation(NULL
);
118 sock_release(socket
);
120 destroy_workqueue(afs_async_calls
);
122 _leave(" = %d", ret
);
127 * close the RxRPC socket AFS was using
129 void afs_close_socket(void)
133 if (afs_spare_incoming_call
) {
134 atomic_inc(&afs_outstanding_calls
);
135 afs_free_call(afs_spare_incoming_call
);
136 afs_spare_incoming_call
= NULL
;
139 _debug("outstanding %u", atomic_read(&afs_outstanding_calls
));
140 wait_on_atomic_t(&afs_outstanding_calls
, afs_wait_atomic_t
,
141 TASK_UNINTERRUPTIBLE
);
142 _debug("no outstanding calls");
144 flush_workqueue(afs_async_calls
);
145 kernel_sock_shutdown(afs_socket
, SHUT_RDWR
);
146 flush_workqueue(afs_async_calls
);
147 sock_release(afs_socket
);
150 destroy_workqueue(afs_async_calls
);
157 static void afs_free_call(struct afs_call
*call
)
159 _debug("DONE %p{%s} [%d]",
160 call
, call
->type
->name
, atomic_read(&afs_outstanding_calls
));
162 ASSERTCMP(call
->rxcall
, ==, NULL
);
163 ASSERT(!work_pending(&call
->async_work
));
164 ASSERT(call
->type
->name
!= NULL
);
166 kfree(call
->request
);
169 if (atomic_dec_and_test(&afs_outstanding_calls
))
170 wake_up_atomic_t(&afs_outstanding_calls
);
174 * End a call but do not free it
176 static void afs_end_call_nofree(struct afs_call
*call
)
179 rxrpc_kernel_end_call(afs_socket
, call
->rxcall
);
182 if (call
->type
->destructor
)
183 call
->type
->destructor(call
);
187 * End a call and free it
189 static void afs_end_call(struct afs_call
*call
)
191 afs_end_call_nofree(call
);
196 * allocate a call with flat request and reply buffers
198 struct afs_call
*afs_alloc_flat_call(const struct afs_call_type
*type
,
199 size_t request_size
, size_t reply_max
)
201 struct afs_call
*call
;
203 call
= kzalloc(sizeof(*call
), GFP_NOFS
);
207 _debug("CALL %p{%s} [%d]",
208 call
, type
->name
, atomic_read(&afs_outstanding_calls
));
209 atomic_inc(&afs_outstanding_calls
);
212 call
->request_size
= request_size
;
213 call
->reply_max
= reply_max
;
216 call
->request
= kmalloc(request_size
, GFP_NOFS
);
222 call
->buffer
= kmalloc(reply_max
, GFP_NOFS
);
227 init_waitqueue_head(&call
->waitq
);
237 * clean up a call with flat buffer
239 void afs_flat_call_destructor(struct afs_call
*call
)
243 kfree(call
->request
);
244 call
->request
= NULL
;
250 * attach the data from a bunch of pages on an inode to a call
252 static int afs_send_pages(struct afs_call
*call
, struct msghdr
*msg
,
255 struct page
*pages
[8];
256 unsigned count
, n
, loop
, offset
, to
;
257 pgoff_t first
= call
->first
, last
= call
->last
;
262 offset
= call
->first_offset
;
263 call
->first_offset
= 0;
266 _debug("attach %lx-%lx", first
, last
);
268 count
= last
- first
+ 1;
269 if (count
> ARRAY_SIZE(pages
))
270 count
= ARRAY_SIZE(pages
);
271 n
= find_get_pages_contig(call
->mapping
, first
, count
, pages
);
272 ASSERTCMP(n
, ==, count
);
278 if (first
+ loop
>= last
)
281 msg
->msg_flags
= MSG_MORE
;
282 iov
->iov_base
= kmap(pages
[loop
]) + offset
;
283 iov
->iov_len
= to
- offset
;
286 _debug("- range %u-%u%s",
287 offset
, to
, msg
->msg_flags
? " [more]" : "");
288 iov_iter_kvec(&msg
->msg_iter
, WRITE
| ITER_KVEC
,
289 iov
, 1, to
- offset
);
291 /* have to change the state *before* sending the last
292 * packet as RxRPC might give us the reply before it
293 * returns from sending the request */
294 if (first
+ loop
>= last
)
295 call
->state
= AFS_CALL_AWAIT_REPLY
;
296 ret
= rxrpc_kernel_send_data(afs_socket
, call
->rxcall
,
301 } while (++loop
< count
);
304 for (loop
= 0; loop
< count
; loop
++)
305 put_page(pages
[loop
]);
308 } while (first
<= last
);
310 _leave(" = %d", ret
);
317 int afs_make_call(struct in_addr
*addr
, struct afs_call
*call
, gfp_t gfp
,
318 const struct afs_wait_mode
*wait_mode
)
320 struct sockaddr_rxrpc srx
;
321 struct rxrpc_call
*rxcall
;
326 _enter("%x,{%d},", addr
->s_addr
, ntohs(call
->port
));
328 ASSERT(call
->type
!= NULL
);
329 ASSERT(call
->type
->name
!= NULL
);
331 _debug("____MAKE %p{%s,%x} [%d]____",
332 call
, call
->type
->name
, key_serial(call
->key
),
333 atomic_read(&afs_outstanding_calls
));
335 call
->wait_mode
= wait_mode
;
336 INIT_WORK(&call
->async_work
, afs_process_async_call
);
338 memset(&srx
, 0, sizeof(srx
));
339 srx
.srx_family
= AF_RXRPC
;
340 srx
.srx_service
= call
->service_id
;
341 srx
.transport_type
= SOCK_DGRAM
;
342 srx
.transport_len
= sizeof(srx
.transport
.sin
);
343 srx
.transport
.sin
.sin_family
= AF_INET
;
344 srx
.transport
.sin
.sin_port
= call
->port
;
345 memcpy(&srx
.transport
.sin
.sin_addr
, addr
, 4);
348 rxcall
= rxrpc_kernel_begin_call(afs_socket
, &srx
, call
->key
,
349 (unsigned long) call
, gfp
,
350 wait_mode
->notify_rx
);
352 if (IS_ERR(rxcall
)) {
353 ret
= PTR_ERR(rxcall
);
354 goto error_kill_call
;
357 call
->rxcall
= rxcall
;
359 /* send the request */
360 iov
[0].iov_base
= call
->request
;
361 iov
[0].iov_len
= call
->request_size
;
365 iov_iter_kvec(&msg
.msg_iter
, WRITE
| ITER_KVEC
, iov
, 1,
367 msg
.msg_control
= NULL
;
368 msg
.msg_controllen
= 0;
369 msg
.msg_flags
= (call
->send_pages
? MSG_MORE
: 0);
371 /* have to change the state *before* sending the last packet as RxRPC
372 * might give us the reply before it returns from sending the
374 if (!call
->send_pages
)
375 call
->state
= AFS_CALL_AWAIT_REPLY
;
376 ret
= rxrpc_kernel_send_data(afs_socket
, rxcall
,
377 &msg
, call
->request_size
);
381 if (call
->send_pages
) {
382 ret
= afs_send_pages(call
, &msg
, iov
);
387 /* at this point, an async call may no longer exist as it may have
388 * already completed */
389 return wait_mode
->wait(call
);
392 rxrpc_kernel_abort_call(afs_socket
, rxcall
, RX_USER_ABORT
, -ret
, "KSD");
395 _leave(" = %d", ret
);
400 * deliver messages to a call
402 static void afs_deliver_to_call(struct afs_call
*call
)
407 _enter("%s", call
->type
->name
);
409 while (call
->state
== AFS_CALL_AWAIT_REPLY
||
410 call
->state
== AFS_CALL_AWAIT_OP_ID
||
411 call
->state
== AFS_CALL_AWAIT_REQUEST
||
412 call
->state
== AFS_CALL_AWAIT_ACK
414 if (call
->state
== AFS_CALL_AWAIT_ACK
) {
416 ret
= rxrpc_kernel_recv_data(afs_socket
, call
->rxcall
,
417 NULL
, 0, &offset
, false,
419 if (ret
== -EINPROGRESS
|| ret
== -EAGAIN
)
422 call
->state
= AFS_CALL_COMPLETE
;
428 ret
= call
->type
->deliver(call
);
431 if (call
->state
== AFS_CALL_AWAIT_REPLY
)
432 call
->state
= AFS_CALL_COMPLETE
;
438 abort_code
= RX_CALL_DEAD
;
439 rxrpc_kernel_abort_call(afs_socket
, call
->rxcall
,
440 abort_code
, -ret
, "KNC");
443 abort_code
= RX_INVALID_OPERATION
;
444 rxrpc_kernel_abort_call(afs_socket
, call
->rxcall
,
445 abort_code
, -ret
, "KIV");
451 abort_code
= RXGEN_CC_UNMARSHAL
;
452 if (call
->state
!= AFS_CALL_AWAIT_REPLY
)
453 abort_code
= RXGEN_SS_UNMARSHAL
;
454 rxrpc_kernel_abort_call(afs_socket
, call
->rxcall
,
455 abort_code
, EBADMSG
, "KUM");
461 if (call
->state
== AFS_CALL_COMPLETE
&& call
->incoming
)
469 call
->state
= AFS_CALL_COMPLETE
;
474 * wait synchronously for a call to complete
476 static int afs_wait_for_call_to_complete(struct afs_call
*call
)
478 const char *abort_why
;
481 DECLARE_WAITQUEUE(myself
, current
);
485 add_wait_queue(&call
->waitq
, &myself
);
487 set_current_state(TASK_INTERRUPTIBLE
);
489 /* deliver any messages that are in the queue */
490 if (call
->state
< AFS_CALL_COMPLETE
&& call
->need_attention
) {
491 call
->need_attention
= false;
492 __set_current_state(TASK_RUNNING
);
493 afs_deliver_to_call(call
);
499 if (call
->state
== AFS_CALL_COMPLETE
)
503 if (signal_pending(current
))
508 remove_wait_queue(&call
->waitq
, &myself
);
509 __set_current_state(TASK_RUNNING
);
512 if (call
->state
< AFS_CALL_COMPLETE
) {
513 _debug("call incomplete");
514 rxrpc_kernel_abort_call(afs_socket
, call
->rxcall
,
515 RX_CALL_DEAD
, -ret
, abort_why
);
518 _debug("call complete");
520 _leave(" = %d", ret
);
525 * wake up a waiting call
527 static void afs_wake_up_call_waiter(struct sock
*sk
, struct rxrpc_call
*rxcall
,
528 unsigned long call_user_ID
)
530 struct afs_call
*call
= (struct afs_call
*)call_user_ID
;
532 call
->need_attention
= true;
533 wake_up(&call
->waitq
);
537 * wake up an asynchronous call
539 static void afs_wake_up_async_call(struct sock
*sk
, struct rxrpc_call
*rxcall
,
540 unsigned long call_user_ID
)
542 struct afs_call
*call
= (struct afs_call
*)call_user_ID
;
544 call
->need_attention
= true;
545 queue_work(afs_async_calls
, &call
->async_work
);
549 * put a call into asynchronous mode
550 * - mustn't touch the call descriptor as the call my have completed by the
553 static int afs_dont_wait_for_call_to_complete(struct afs_call
*call
)
560 * delete an asynchronous call
562 static void afs_delete_async_call(struct work_struct
*work
)
564 struct afs_call
*call
= container_of(work
, struct afs_call
, async_work
);
574 * perform processing on an asynchronous call
576 static void afs_process_async_call(struct work_struct
*work
)
578 struct afs_call
*call
= container_of(work
, struct afs_call
, async_work
);
582 if (call
->state
< AFS_CALL_COMPLETE
&& call
->need_attention
) {
583 call
->need_attention
= false;
584 afs_deliver_to_call(call
);
587 if (call
->state
== AFS_CALL_COMPLETE
&& call
->wait_mode
) {
588 if (call
->wait_mode
->async_complete
)
589 call
->wait_mode
->async_complete(call
->reply
,
594 afs_end_call_nofree(call
);
596 /* we can't just delete the call because the work item may be
598 call
->async_work
.func
= afs_delete_async_call
;
599 queue_work(afs_async_calls
, &call
->async_work
);
605 static void afs_rx_attach(struct rxrpc_call
*rxcall
, unsigned long user_call_ID
)
607 struct afs_call
*call
= (struct afs_call
*)user_call_ID
;
609 call
->rxcall
= rxcall
;
613 * Charge the incoming call preallocation.
615 static void afs_charge_preallocation(struct work_struct
*work
)
617 struct afs_call
*call
= afs_spare_incoming_call
;
621 call
= kzalloc(sizeof(struct afs_call
), GFP_KERNEL
);
625 INIT_WORK(&call
->async_work
, afs_process_async_call
);
626 call
->wait_mode
= &afs_async_incoming_call
;
627 call
->type
= &afs_RXCMxxxx
;
628 init_waitqueue_head(&call
->waitq
);
629 call
->state
= AFS_CALL_AWAIT_OP_ID
;
632 if (rxrpc_kernel_charge_accept(afs_socket
,
633 afs_wake_up_async_call
,
640 afs_spare_incoming_call
= call
;
644 * Discard a preallocated call when a socket is shut down.
646 static void afs_rx_discard_new_call(struct rxrpc_call
*rxcall
,
647 unsigned long user_call_ID
)
649 struct afs_call
*call
= (struct afs_call
*)user_call_ID
;
651 atomic_inc(&afs_outstanding_calls
);
657 * Notification of an incoming call.
659 static void afs_rx_new_call(struct sock
*sk
, struct rxrpc_call
*rxcall
,
660 unsigned long user_call_ID
)
662 atomic_inc(&afs_outstanding_calls
);
663 queue_work(afs_wq
, &afs_charge_preallocation_work
);
667 * Grab the operation ID from an incoming cache manager call. The socket
668 * buffer is discarded on error or if we don't yet have sufficient data.
670 static int afs_deliver_cm_op_id(struct afs_call
*call
)
674 _enter("{%zu}", call
->offset
);
676 ASSERTCMP(call
->offset
, <, 4);
678 /* the operation ID forms the first four bytes of the request data */
679 ret
= afs_extract_data(call
, &call
->operation_ID
, 4, true);
683 call
->state
= AFS_CALL_AWAIT_REQUEST
;
686 /* ask the cache manager to route the call (it'll change the call type
688 if (!afs_cm_incoming_call(call
))
691 /* pass responsibility for the remainer of this message off to the
692 * cache manager op */
693 return call
->type
->deliver(call
);
697 * send an empty reply
699 void afs_send_empty_reply(struct afs_call
*call
)
707 iov_iter_kvec(&msg
.msg_iter
, WRITE
| ITER_KVEC
, NULL
, 0, 0);
708 msg
.msg_control
= NULL
;
709 msg
.msg_controllen
= 0;
712 call
->state
= AFS_CALL_AWAIT_ACK
;
713 switch (rxrpc_kernel_send_data(afs_socket
, call
->rxcall
, &msg
, 0)) {
715 _leave(" [replied]");
720 rxrpc_kernel_abort_call(afs_socket
, call
->rxcall
,
721 RX_USER_ABORT
, ENOMEM
, "KOO");
730 * send a simple reply
732 void afs_send_simple_reply(struct afs_call
*call
, const void *buf
, size_t len
)
740 iov
[0].iov_base
= (void *) buf
;
741 iov
[0].iov_len
= len
;
744 iov_iter_kvec(&msg
.msg_iter
, WRITE
| ITER_KVEC
, iov
, 1, len
);
745 msg
.msg_control
= NULL
;
746 msg
.msg_controllen
= 0;
749 call
->state
= AFS_CALL_AWAIT_ACK
;
750 n
= rxrpc_kernel_send_data(afs_socket
, call
->rxcall
, &msg
, len
);
753 _leave(" [replied]");
759 rxrpc_kernel_abort_call(afs_socket
, call
->rxcall
,
760 RX_USER_ABORT
, ENOMEM
, "KOO");
767 * Extract a piece of data from the received data socket buffers.
769 int afs_extract_data(struct afs_call
*call
, void *buf
, size_t count
,
774 _enter("{%s,%zu},,%zu,%d",
775 call
->type
->name
, call
->offset
, count
, want_more
);
777 ASSERTCMP(call
->offset
, <=, count
);
779 ret
= rxrpc_kernel_recv_data(afs_socket
, call
->rxcall
,
780 buf
, count
, &call
->offset
,
781 want_more
, &call
->abort_code
);
782 if (ret
== 0 || ret
== -EAGAIN
)
786 switch (call
->state
) {
787 case AFS_CALL_AWAIT_REPLY
:
788 call
->state
= AFS_CALL_COMPLETE
;
790 case AFS_CALL_AWAIT_REQUEST
:
791 call
->state
= AFS_CALL_REPLYING
;
799 if (ret
== -ECONNABORTED
)
800 call
->error
= call
->type
->abort_to_error(call
->abort_code
);
803 call
->state
= AFS_CALL_COMPLETE
;