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 static struct socket
*afs_socket
; /* my RxRPC socket */
20 static struct workqueue_struct
*afs_async_calls
;
21 static atomic_t afs_outstanding_calls
;
22 static atomic_t afs_outstanding_skbs
;
24 static void afs_wake_up_call_waiter(struct afs_call
*);
25 static int afs_wait_for_call_to_complete(struct afs_call
*);
26 static void afs_wake_up_async_call(struct afs_call
*);
27 static int afs_dont_wait_for_call_to_complete(struct afs_call
*);
28 static void afs_process_async_call(struct afs_call
*);
29 static void afs_rx_interceptor(struct sock
*, unsigned long, struct sk_buff
*);
30 static int afs_deliver_cm_op_id(struct afs_call
*, struct sk_buff
*, bool);
32 /* synchronous call management */
33 const struct afs_wait_mode afs_sync_call
= {
34 .rx_wakeup
= afs_wake_up_call_waiter
,
35 .wait
= afs_wait_for_call_to_complete
,
38 /* asynchronous call management */
39 const struct afs_wait_mode afs_async_call
= {
40 .rx_wakeup
= afs_wake_up_async_call
,
41 .wait
= afs_dont_wait_for_call_to_complete
,
44 /* asynchronous incoming call management */
45 static const struct afs_wait_mode afs_async_incoming_call
= {
46 .rx_wakeup
= afs_wake_up_async_call
,
49 /* asynchronous incoming call initial processing */
50 static const struct afs_call_type afs_RXCMxxxx
= {
52 .deliver
= afs_deliver_cm_op_id
,
53 .abort_to_error
= afs_abort_to_error
,
56 static void afs_collect_incoming_call(struct work_struct
*);
58 static struct sk_buff_head afs_incoming_calls
;
59 static DECLARE_WORK(afs_collect_incoming_call_work
, afs_collect_incoming_call
);
61 static void afs_async_workfn(struct work_struct
*work
)
63 struct afs_call
*call
= container_of(work
, struct afs_call
, async_work
);
65 call
->async_workfn(call
);
68 static int afs_wait_atomic_t(atomic_t
*p
)
75 * open an RxRPC socket and bind it to be a server for callback notifications
76 * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT
78 int afs_open_socket(void)
80 struct sockaddr_rxrpc srx
;
81 struct socket
*socket
;
86 skb_queue_head_init(&afs_incoming_calls
);
88 afs_async_calls
= create_singlethread_workqueue("kafsd");
89 if (!afs_async_calls
) {
90 _leave(" = -ENOMEM [wq]");
94 ret
= sock_create_kern(&init_net
, AF_RXRPC
, SOCK_DGRAM
, PF_INET
, &socket
);
96 destroy_workqueue(afs_async_calls
);
97 _leave(" = %d [socket]", ret
);
101 socket
->sk
->sk_allocation
= GFP_NOFS
;
103 /* bind the callback manager's address to make this a server socket */
104 srx
.srx_family
= AF_RXRPC
;
105 srx
.srx_service
= CM_SERVICE
;
106 srx
.transport_type
= SOCK_DGRAM
;
107 srx
.transport_len
= sizeof(srx
.transport
.sin
);
108 srx
.transport
.sin
.sin_family
= AF_INET
;
109 srx
.transport
.sin
.sin_port
= htons(AFS_CM_PORT
);
110 memset(&srx
.transport
.sin
.sin_addr
, 0,
111 sizeof(srx
.transport
.sin
.sin_addr
));
113 ret
= kernel_bind(socket
, (struct sockaddr
*) &srx
, sizeof(srx
));
115 sock_release(socket
);
116 destroy_workqueue(afs_async_calls
);
117 _leave(" = %d [bind]", ret
);
121 rxrpc_kernel_intercept_rx_messages(socket
, afs_rx_interceptor
);
129 * close the RxRPC socket AFS was using
131 void afs_close_socket(void)
135 wait_on_atomic_t(&afs_outstanding_calls
, afs_wait_atomic_t
,
136 TASK_UNINTERRUPTIBLE
);
137 _debug("no outstanding calls");
139 sock_release(afs_socket
);
142 destroy_workqueue(afs_async_calls
);
144 ASSERTCMP(atomic_read(&afs_outstanding_skbs
), ==, 0);
149 * note that the data in a socket buffer is now delivered and that the buffer
152 static void afs_data_delivered(struct sk_buff
*skb
)
155 _debug("DLVR NULL [%d]", atomic_read(&afs_outstanding_skbs
));
158 _debug("DLVR %p{%u} [%d]",
159 skb
, skb
->mark
, atomic_read(&afs_outstanding_skbs
));
160 if (atomic_dec_return(&afs_outstanding_skbs
) == -1)
162 rxrpc_kernel_data_delivered(skb
);
167 * free a socket buffer
169 static void afs_free_skb(struct sk_buff
*skb
)
172 _debug("FREE NULL [%d]", atomic_read(&afs_outstanding_skbs
));
175 _debug("FREE %p{%u} [%d]",
176 skb
, skb
->mark
, atomic_read(&afs_outstanding_skbs
));
177 if (atomic_dec_return(&afs_outstanding_skbs
) == -1)
179 rxrpc_kernel_free_skb(skb
);
186 static void afs_free_call(struct afs_call
*call
)
188 _debug("DONE %p{%s} [%d]",
189 call
, call
->type
->name
, atomic_read(&afs_outstanding_calls
));
191 ASSERTCMP(call
->rxcall
, ==, NULL
);
192 ASSERT(!work_pending(&call
->async_work
));
193 ASSERT(skb_queue_empty(&call
->rx_queue
));
194 ASSERT(call
->type
->name
!= NULL
);
196 kfree(call
->request
);
199 if (atomic_dec_and_test(&afs_outstanding_calls
))
200 wake_up_atomic_t(&afs_outstanding_calls
);
204 * End a call but do not free it
206 static void afs_end_call_nofree(struct afs_call
*call
)
209 rxrpc_kernel_end_call(call
->rxcall
);
212 if (call
->type
->destructor
)
213 call
->type
->destructor(call
);
217 * End a call and free it
219 static void afs_end_call(struct afs_call
*call
)
221 afs_end_call_nofree(call
);
226 * allocate a call with flat request and reply buffers
228 struct afs_call
*afs_alloc_flat_call(const struct afs_call_type
*type
,
229 size_t request_size
, size_t reply_size
)
231 struct afs_call
*call
;
233 call
= kzalloc(sizeof(*call
), GFP_NOFS
);
237 _debug("CALL %p{%s} [%d]",
238 call
, type
->name
, atomic_read(&afs_outstanding_calls
));
239 atomic_inc(&afs_outstanding_calls
);
242 call
->request_size
= request_size
;
243 call
->reply_max
= reply_size
;
246 call
->request
= kmalloc(request_size
, GFP_NOFS
);
252 call
->buffer
= kmalloc(reply_size
, GFP_NOFS
);
257 init_waitqueue_head(&call
->waitq
);
258 skb_queue_head_init(&call
->rx_queue
);
268 * clean up a call with flat buffer
270 void afs_flat_call_destructor(struct afs_call
*call
)
274 kfree(call
->request
);
275 call
->request
= NULL
;
281 * attach the data from a bunch of pages on an inode to a call
283 static int afs_send_pages(struct afs_call
*call
, struct msghdr
*msg
,
286 struct page
*pages
[8];
287 unsigned count
, n
, loop
, offset
, to
;
288 pgoff_t first
= call
->first
, last
= call
->last
;
293 offset
= call
->first_offset
;
294 call
->first_offset
= 0;
297 _debug("attach %lx-%lx", first
, last
);
299 count
= last
- first
+ 1;
300 if (count
> ARRAY_SIZE(pages
))
301 count
= ARRAY_SIZE(pages
);
302 n
= find_get_pages_contig(call
->mapping
, first
, count
, pages
);
303 ASSERTCMP(n
, ==, count
);
309 if (first
+ loop
>= last
)
312 msg
->msg_flags
= MSG_MORE
;
313 iov
->iov_base
= kmap(pages
[loop
]) + offset
;
314 iov
->iov_len
= to
- offset
;
317 _debug("- range %u-%u%s",
318 offset
, to
, msg
->msg_flags
? " [more]" : "");
319 iov_iter_kvec(&msg
->msg_iter
, WRITE
| ITER_KVEC
,
320 iov
, 1, to
- offset
);
322 /* have to change the state *before* sending the last
323 * packet as RxRPC might give us the reply before it
324 * returns from sending the request */
325 if (first
+ loop
>= last
)
326 call
->state
= AFS_CALL_AWAIT_REPLY
;
327 ret
= rxrpc_kernel_send_data(call
->rxcall
, msg
,
332 } while (++loop
< count
);
335 for (loop
= 0; loop
< count
; loop
++)
336 put_page(pages
[loop
]);
339 } while (first
<= last
);
341 _leave(" = %d", ret
);
348 int afs_make_call(struct in_addr
*addr
, struct afs_call
*call
, gfp_t gfp
,
349 const struct afs_wait_mode
*wait_mode
)
351 struct sockaddr_rxrpc srx
;
352 struct rxrpc_call
*rxcall
;
358 _enter("%x,{%d},", addr
->s_addr
, ntohs(call
->port
));
360 ASSERT(call
->type
!= NULL
);
361 ASSERT(call
->type
->name
!= NULL
);
363 _debug("____MAKE %p{%s,%x} [%d]____",
364 call
, call
->type
->name
, key_serial(call
->key
),
365 atomic_read(&afs_outstanding_calls
));
367 call
->wait_mode
= wait_mode
;
368 call
->async_workfn
= afs_process_async_call
;
369 INIT_WORK(&call
->async_work
, afs_async_workfn
);
371 memset(&srx
, 0, sizeof(srx
));
372 srx
.srx_family
= AF_RXRPC
;
373 srx
.srx_service
= call
->service_id
;
374 srx
.transport_type
= SOCK_DGRAM
;
375 srx
.transport_len
= sizeof(srx
.transport
.sin
);
376 srx
.transport
.sin
.sin_family
= AF_INET
;
377 srx
.transport
.sin
.sin_port
= call
->port
;
378 memcpy(&srx
.transport
.sin
.sin_addr
, addr
, 4);
381 rxcall
= rxrpc_kernel_begin_call(afs_socket
, &srx
, call
->key
,
382 (unsigned long) call
, gfp
);
384 if (IS_ERR(rxcall
)) {
385 ret
= PTR_ERR(rxcall
);
386 goto error_kill_call
;
389 call
->rxcall
= rxcall
;
391 /* send the request */
392 iov
[0].iov_base
= call
->request
;
393 iov
[0].iov_len
= call
->request_size
;
397 iov_iter_kvec(&msg
.msg_iter
, WRITE
| ITER_KVEC
, iov
, 1,
399 msg
.msg_control
= NULL
;
400 msg
.msg_controllen
= 0;
401 msg
.msg_flags
= (call
->send_pages
? MSG_MORE
: 0);
403 /* have to change the state *before* sending the last packet as RxRPC
404 * might give us the reply before it returns from sending the
406 if (!call
->send_pages
)
407 call
->state
= AFS_CALL_AWAIT_REPLY
;
408 ret
= rxrpc_kernel_send_data(rxcall
, &msg
, call
->request_size
);
412 if (call
->send_pages
) {
413 ret
= afs_send_pages(call
, &msg
, iov
);
418 /* at this point, an async call may no longer exist as it may have
419 * already completed */
420 return wait_mode
->wait(call
);
423 rxrpc_kernel_abort_call(rxcall
, RX_USER_ABORT
);
424 while ((skb
= skb_dequeue(&call
->rx_queue
)))
428 _leave(" = %d", ret
);
433 * Handles intercepted messages that were arriving in the socket's Rx queue.
435 * Called from the AF_RXRPC call processor in waitqueue process context. For
436 * each call, it is guaranteed this will be called in order of packet to be
439 static void afs_rx_interceptor(struct sock
*sk
, unsigned long user_call_ID
,
442 struct afs_call
*call
= (struct afs_call
*) user_call_ID
;
444 _enter("%p,,%u", call
, skb
->mark
);
446 _debug("ICPT %p{%u} [%d]",
447 skb
, skb
->mark
, atomic_read(&afs_outstanding_skbs
));
449 ASSERTCMP(sk
, ==, afs_socket
->sk
);
450 atomic_inc(&afs_outstanding_skbs
);
453 /* its an incoming call for our callback service */
454 skb_queue_tail(&afs_incoming_calls
, skb
);
455 queue_work(afs_wq
, &afs_collect_incoming_call_work
);
457 /* route the messages directly to the appropriate call */
458 skb_queue_tail(&call
->rx_queue
, skb
);
459 call
->wait_mode
->rx_wakeup(call
);
466 * deliver messages to a call
468 static void afs_deliver_to_call(struct afs_call
*call
)
477 while ((call
->state
== AFS_CALL_AWAIT_REPLY
||
478 call
->state
== AFS_CALL_AWAIT_OP_ID
||
479 call
->state
== AFS_CALL_AWAIT_REQUEST
||
480 call
->state
== AFS_CALL_AWAIT_ACK
) &&
481 (skb
= skb_dequeue(&call
->rx_queue
))) {
483 case RXRPC_SKB_MARK_DATA
:
485 last
= rxrpc_kernel_is_data_last(skb
);
486 ret
= call
->type
->deliver(call
, skb
, last
);
490 call
->state
== AFS_CALL_AWAIT_REPLY
)
491 call
->state
= AFS_CALL_COMPLETE
;
494 abort_code
= RX_CALL_DEAD
;
497 abort_code
= RX_INVALID_OPERATION
;
500 abort_code
= RXGEN_CC_UNMARSHAL
;
501 if (call
->state
!= AFS_CALL_AWAIT_REPLY
)
502 abort_code
= RXGEN_SS_UNMARSHAL
;
504 rxrpc_kernel_abort_call(call
->rxcall
,
507 call
->state
= AFS_CALL_ERROR
;
510 afs_data_delivered(skb
);
513 case RXRPC_SKB_MARK_FINAL_ACK
:
515 call
->state
= AFS_CALL_COMPLETE
;
517 case RXRPC_SKB_MARK_BUSY
:
519 call
->error
= -EBUSY
;
520 call
->state
= AFS_CALL_BUSY
;
522 case RXRPC_SKB_MARK_REMOTE_ABORT
:
523 abort_code
= rxrpc_kernel_get_abort_code(skb
);
524 call
->error
= call
->type
->abort_to_error(abort_code
);
525 call
->state
= AFS_CALL_ABORTED
;
526 _debug("Rcv ABORT %u -> %d", abort_code
, call
->error
);
528 case RXRPC_SKB_MARK_LOCAL_ABORT
:
529 abort_code
= rxrpc_kernel_get_abort_code(skb
);
530 call
->error
= call
->type
->abort_to_error(abort_code
);
531 call
->state
= AFS_CALL_ABORTED
;
532 _debug("Loc ABORT %u -> %d", abort_code
, call
->error
);
534 case RXRPC_SKB_MARK_NET_ERROR
:
535 call
->error
= -rxrpc_kernel_get_error_number(skb
);
536 call
->state
= AFS_CALL_ERROR
;
537 _debug("Rcv NET ERROR %d", call
->error
);
539 case RXRPC_SKB_MARK_LOCAL_ERROR
:
540 call
->error
= -rxrpc_kernel_get_error_number(skb
);
541 call
->state
= AFS_CALL_ERROR
;
542 _debug("Rcv LOCAL ERROR %d", call
->error
);
552 /* make sure the queue is empty if the call is done with (we might have
553 * aborted the call early because of an unmarshalling error) */
554 if (call
->state
>= AFS_CALL_COMPLETE
) {
555 while ((skb
= skb_dequeue(&call
->rx_queue
)))
565 * wait synchronously for a call to complete
567 static int afs_wait_for_call_to_complete(struct afs_call
*call
)
572 DECLARE_WAITQUEUE(myself
, current
);
576 add_wait_queue(&call
->waitq
, &myself
);
578 set_current_state(TASK_INTERRUPTIBLE
);
580 /* deliver any messages that are in the queue */
581 if (!skb_queue_empty(&call
->rx_queue
)) {
582 __set_current_state(TASK_RUNNING
);
583 afs_deliver_to_call(call
);
588 if (call
->state
>= AFS_CALL_COMPLETE
)
591 if (signal_pending(current
))
596 remove_wait_queue(&call
->waitq
, &myself
);
597 __set_current_state(TASK_RUNNING
);
600 if (call
->state
< AFS_CALL_COMPLETE
) {
601 _debug("call incomplete");
602 rxrpc_kernel_abort_call(call
->rxcall
, RX_CALL_DEAD
);
603 while ((skb
= skb_dequeue(&call
->rx_queue
)))
607 _debug("call complete");
609 _leave(" = %d", ret
);
614 * wake up a waiting call
616 static void afs_wake_up_call_waiter(struct afs_call
*call
)
618 wake_up(&call
->waitq
);
622 * wake up an asynchronous call
624 static void afs_wake_up_async_call(struct afs_call
*call
)
627 queue_work(afs_async_calls
, &call
->async_work
);
631 * put a call into asynchronous mode
632 * - mustn't touch the call descriptor as the call my have completed by the
635 static int afs_dont_wait_for_call_to_complete(struct afs_call
*call
)
642 * delete an asynchronous call
644 static void afs_delete_async_call(struct afs_call
*call
)
654 * perform processing on an asynchronous call
655 * - on a multiple-thread workqueue this work item may try to run on several
656 * CPUs at the same time
658 static void afs_process_async_call(struct afs_call
*call
)
662 if (!skb_queue_empty(&call
->rx_queue
))
663 afs_deliver_to_call(call
);
665 if (call
->state
>= AFS_CALL_COMPLETE
&& call
->wait_mode
) {
666 if (call
->wait_mode
->async_complete
)
667 call
->wait_mode
->async_complete(call
->reply
,
672 afs_end_call_nofree(call
);
674 /* we can't just delete the call because the work item may be
676 call
->async_workfn
= afs_delete_async_call
;
677 queue_work(afs_async_calls
, &call
->async_work
);
684 * empty a socket buffer into a flat reply buffer
686 void afs_transfer_reply(struct afs_call
*call
, struct sk_buff
*skb
)
688 size_t len
= skb
->len
;
690 if (skb_copy_bits(skb
, 0, call
->buffer
+ call
->reply_size
, len
) < 0)
692 call
->reply_size
+= len
;
696 * accept the backlog of incoming calls
698 static void afs_collect_incoming_call(struct work_struct
*work
)
700 struct rxrpc_call
*rxcall
;
701 struct afs_call
*call
= NULL
;
704 while ((skb
= skb_dequeue(&afs_incoming_calls
))) {
707 /* don't need the notification */
711 call
= kzalloc(sizeof(struct afs_call
), GFP_KERNEL
);
713 rxrpc_kernel_reject_call(afs_socket
);
717 call
->async_workfn
= afs_process_async_call
;
718 INIT_WORK(&call
->async_work
, afs_async_workfn
);
719 call
->wait_mode
= &afs_async_incoming_call
;
720 call
->type
= &afs_RXCMxxxx
;
721 init_waitqueue_head(&call
->waitq
);
722 skb_queue_head_init(&call
->rx_queue
);
723 call
->state
= AFS_CALL_AWAIT_OP_ID
;
725 _debug("CALL %p{%s} [%d]",
726 call
, call
->type
->name
,
727 atomic_read(&afs_outstanding_calls
));
728 atomic_inc(&afs_outstanding_calls
);
731 rxcall
= rxrpc_kernel_accept_call(afs_socket
,
732 (unsigned long) call
);
733 if (!IS_ERR(rxcall
)) {
734 call
->rxcall
= rxcall
;
744 * grab the operation ID from an incoming cache manager call
746 static int afs_deliver_cm_op_id(struct afs_call
*call
, struct sk_buff
*skb
,
749 size_t len
= skb
->len
;
750 void *oibuf
= (void *) &call
->operation_ID
;
752 _enter("{%u},{%zu},%d", call
->offset
, len
, last
);
754 ASSERTCMP(call
->offset
, <, 4);
756 /* the operation ID forms the first four bytes of the request data */
757 len
= min_t(size_t, len
, 4 - call
->offset
);
758 if (skb_copy_bits(skb
, 0, oibuf
+ call
->offset
, len
) < 0)
760 if (!pskb_pull(skb
, len
))
764 if (call
->offset
< 4) {
766 _leave(" = -EBADMSG [op ID short]");
769 _leave(" = 0 [incomplete]");
773 call
->state
= AFS_CALL_AWAIT_REQUEST
;
775 /* ask the cache manager to route the call (it'll change the call type
777 if (!afs_cm_incoming_call(call
))
780 /* pass responsibility for the remainer of this message off to the
781 * cache manager op */
782 return call
->type
->deliver(call
, skb
, last
);
786 * send an empty reply
788 void afs_send_empty_reply(struct afs_call
*call
)
796 iov_iter_kvec(&msg
.msg_iter
, WRITE
| ITER_KVEC
, NULL
, 0, 0);
797 msg
.msg_control
= NULL
;
798 msg
.msg_controllen
= 0;
801 call
->state
= AFS_CALL_AWAIT_ACK
;
802 switch (rxrpc_kernel_send_data(call
->rxcall
, &msg
, 0)) {
804 _leave(" [replied]");
809 rxrpc_kernel_abort_call(call
->rxcall
, RX_USER_ABORT
);
818 * send a simple reply
820 void afs_send_simple_reply(struct afs_call
*call
, const void *buf
, size_t len
)
828 iov
[0].iov_base
= (void *) buf
;
829 iov
[0].iov_len
= len
;
832 iov_iter_kvec(&msg
.msg_iter
, WRITE
| ITER_KVEC
, iov
, 1, len
);
833 msg
.msg_control
= NULL
;
834 msg
.msg_controllen
= 0;
837 call
->state
= AFS_CALL_AWAIT_ACK
;
838 n
= rxrpc_kernel_send_data(call
->rxcall
, &msg
, len
);
841 _leave(" [replied]");
847 rxrpc_kernel_abort_call(call
->rxcall
, RX_USER_ABORT
);
854 * extract a piece of data from the received data socket buffers
856 int afs_extract_data(struct afs_call
*call
, struct sk_buff
*skb
,
857 bool last
, void *buf
, size_t count
)
859 size_t len
= skb
->len
;
861 _enter("{%u},{%zu},%d,,%zu", call
->offset
, len
, last
, count
);
863 ASSERTCMP(call
->offset
, <, count
);
865 len
= min_t(size_t, len
, count
- call
->offset
);
866 if (skb_copy_bits(skb
, 0, buf
+ call
->offset
, len
) < 0 ||
867 !pskb_pull(skb
, len
))
871 if (call
->offset
< count
) {
873 _leave(" = -EBADMSG [%d < %zu]", call
->offset
, count
);
876 _leave(" = -EAGAIN");