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
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 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 work_struct *);
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,
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.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 = {
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.deliver = afs_deliver_cm_op_id,
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.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);
62
* open an RxRPC socket and bind it to be a server for callback notifications
63
* - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT
65
int afs_open_socket(void)
67
struct sockaddr_rxrpc srx;
68
struct socket *socket;
73
skb_queue_head_init(&afs_incoming_calls);
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afs_async_calls = create_singlethread_workqueue("kafsd");
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if (!afs_async_calls) {
77
_leave(" = -ENOMEM [wq]");
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ret = sock_create_kern(AF_RXRPC, SOCK_DGRAM, PF_INET, &socket);
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destroy_workqueue(afs_async_calls);
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_leave(" = %d [socket]", ret);
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socket->sk->sk_allocation = GFP_NOFS;
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/* bind the callback manager's address to make this a server socket */
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srx.srx_family = AF_RXRPC;
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srx.srx_service = CM_SERVICE;
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srx.transport_type = SOCK_DGRAM;
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srx.transport_len = sizeof(srx.transport.sin);
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srx.transport.sin.sin_family = AF_INET;
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srx.transport.sin.sin_port = htons(AFS_CM_PORT);
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memset(&srx.transport.sin.sin_addr, 0,
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sizeof(srx.transport.sin.sin_addr));
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ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx));
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sock_release(socket);
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destroy_workqueue(afs_async_calls);
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_leave(" = %d [bind]", ret);
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rxrpc_kernel_intercept_rx_messages(socket, afs_rx_interceptor);
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* close the RxRPC socket AFS was using
118
void afs_close_socket(void)
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sock_release(afs_socket);
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destroy_workqueue(afs_async_calls);
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ASSERTCMP(atomic_read(&afs_outstanding_skbs), ==, 0);
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ASSERTCMP(atomic_read(&afs_outstanding_calls), ==, 0);
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* note that the data in a socket buffer is now delivered and that the buffer
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static void afs_data_delivered(struct sk_buff *skb)
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_debug("DLVR NULL [%d]", atomic_read(&afs_outstanding_skbs));
142
_debug("DLVR %p{%u} [%d]",
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skb, skb->mark, atomic_read(&afs_outstanding_skbs));
144
if (atomic_dec_return(&afs_outstanding_skbs) == -1)
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rxrpc_kernel_data_delivered(skb);
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* free a socket buffer
153
static void afs_free_skb(struct sk_buff *skb)
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_debug("FREE NULL [%d]", atomic_read(&afs_outstanding_skbs));
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_debug("FREE %p{%u} [%d]",
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skb, skb->mark, atomic_read(&afs_outstanding_skbs));
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if (atomic_dec_return(&afs_outstanding_skbs) == -1)
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rxrpc_kernel_free_skb(skb);
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static void afs_free_call(struct afs_call *call)
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_debug("DONE %p{%s} [%d]",
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call, call->type->name, atomic_read(&afs_outstanding_calls));
174
if (atomic_dec_return(&afs_outstanding_calls) == -1)
177
ASSERTCMP(call->rxcall, ==, NULL);
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ASSERT(!work_pending(&call->async_work));
179
ASSERT(skb_queue_empty(&call->rx_queue));
180
ASSERT(call->type->name != NULL);
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kfree(call->request);
187
* allocate a call with flat request and reply buffers
189
struct afs_call *afs_alloc_flat_call(const struct afs_call_type *type,
190
size_t request_size, size_t reply_size)
192
struct afs_call *call;
194
call = kzalloc(sizeof(*call), GFP_NOFS);
198
_debug("CALL %p{%s} [%d]",
199
call, type->name, atomic_read(&afs_outstanding_calls));
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atomic_inc(&afs_outstanding_calls);
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call->request_size = request_size;
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call->reply_max = reply_size;
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call->request = kmalloc(request_size, GFP_NOFS);
213
call->buffer = kmalloc(reply_size, GFP_NOFS);
218
init_waitqueue_head(&call->waitq);
219
skb_queue_head_init(&call->rx_queue);
229
* clean up a call with flat buffer
231
void afs_flat_call_destructor(struct afs_call *call)
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kfree(call->request);
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call->request = NULL;
242
* attach the data from a bunch of pages on an inode to a call
244
static int afs_send_pages(struct afs_call *call, struct msghdr *msg,
247
struct page *pages[8];
248
unsigned count, n, loop, offset, to;
249
pgoff_t first = call->first, last = call->last;
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offset = call->first_offset;
255
call->first_offset = 0;
258
_debug("attach %lx-%lx", first, last);
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count = last - first + 1;
261
if (count > ARRAY_SIZE(pages))
262
count = ARRAY_SIZE(pages);
263
n = find_get_pages_contig(call->mapping, first, count, pages);
264
ASSERTCMP(n, ==, count);
270
if (first + loop >= last)
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msg->msg_flags = MSG_MORE;
274
iov->iov_base = kmap(pages[loop]) + offset;
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iov->iov_len = to - offset;
278
_debug("- range %u-%u%s",
279
offset, to, msg->msg_flags ? " [more]" : "");
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msg->msg_iov = (struct iovec *) iov;
283
/* have to change the state *before* sending the last
284
* packet as RxRPC might give us the reply before it
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* returns from sending the request */
286
if (first + loop >= last)
287
call->state = AFS_CALL_AWAIT_REPLY;
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ret = rxrpc_kernel_send_data(call->rxcall, msg,
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} while (++loop < count);
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for (loop = 0; loop < count; loop++)
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put_page(pages[loop]);
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} while (first <= last);
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_leave(" = %d", ret);
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int afs_make_call(struct in_addr *addr, struct afs_call *call, gfp_t gfp,
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const struct afs_wait_mode *wait_mode)
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struct sockaddr_rxrpc srx;
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struct rxrpc_call *rxcall;
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_enter("%x,{%d},", addr->s_addr, ntohs(call->port));
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ASSERT(call->type != NULL);
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ASSERT(call->type->name != NULL);
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_debug("____MAKE %p{%s,%x} [%d]____",
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call, call->type->name, key_serial(call->key),
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atomic_read(&afs_outstanding_calls));
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call->wait_mode = wait_mode;
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INIT_WORK(&call->async_work, afs_process_async_call);
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memset(&srx, 0, sizeof(srx));
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srx.srx_family = AF_RXRPC;
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srx.srx_service = call->service_id;
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srx.transport_type = SOCK_DGRAM;
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srx.transport_len = sizeof(srx.transport.sin);
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srx.transport.sin.sin_family = AF_INET;
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srx.transport.sin.sin_port = call->port;
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memcpy(&srx.transport.sin.sin_addr, addr, 4);
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rxcall = rxrpc_kernel_begin_call(afs_socket, &srx, call->key,
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(unsigned long) call, gfp);
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if (IS_ERR(rxcall)) {
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ret = PTR_ERR(rxcall);
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goto error_kill_call;
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call->rxcall = rxcall;
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/* send the request */
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iov[0].iov_base = call->request;
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iov[0].iov_len = call->request_size;
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msg.msg_iov = (struct iovec *) iov;
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msg.msg_control = NULL;
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msg.msg_controllen = 0;
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msg.msg_flags = (call->send_pages ? MSG_MORE : 0);
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/* have to change the state *before* sending the last packet as RxRPC
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* might give us the reply before it returns from sending the
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if (!call->send_pages)
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call->state = AFS_CALL_AWAIT_REPLY;
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ret = rxrpc_kernel_send_data(rxcall, &msg, call->request_size);
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if (call->send_pages) {
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ret = afs_send_pages(call, &msg, iov);
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/* at this point, an async call may no longer exist as it may have
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* already completed */
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return wait_mode->wait(call);
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rxrpc_kernel_abort_call(rxcall, RX_USER_ABORT);
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rxrpc_kernel_end_call(rxcall);
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call->type->destructor(call);
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_leave(" = %d", ret);
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* handles intercepted messages that were arriving in the socket's Rx queue
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* - called with the socket receive queue lock held to ensure message ordering
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* - called with softirqs disabled
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static void afs_rx_interceptor(struct sock *sk, unsigned long user_call_ID,
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struct afs_call *call = (struct afs_call *) user_call_ID;
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_enter("%p,,%u", call, skb->mark);
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_debug("ICPT %p{%u} [%d]",
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skb, skb->mark, atomic_read(&afs_outstanding_skbs));
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ASSERTCMP(sk, ==, afs_socket->sk);
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atomic_inc(&afs_outstanding_skbs);
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/* its an incoming call for our callback service */
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skb_queue_tail(&afs_incoming_calls, skb);
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queue_work(afs_wq, &afs_collect_incoming_call_work);
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/* route the messages directly to the appropriate call */
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skb_queue_tail(&call->rx_queue, skb);
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call->wait_mode->rx_wakeup(call);
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* deliver messages to a call
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static void afs_deliver_to_call(struct afs_call *call)
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while ((call->state == AFS_CALL_AWAIT_REPLY ||
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call->state == AFS_CALL_AWAIT_OP_ID ||
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call->state == AFS_CALL_AWAIT_REQUEST ||
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call->state == AFS_CALL_AWAIT_ACK) &&
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(skb = skb_dequeue(&call->rx_queue))) {
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case RXRPC_SKB_MARK_DATA:
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last = rxrpc_kernel_is_data_last(skb);
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ret = call->type->deliver(call, skb, last);
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call->state == AFS_CALL_AWAIT_REPLY)
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call->state = AFS_CALL_COMPLETE;
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abort_code = RX_CALL_DEAD;
455
abort_code = RX_INVALID_OPERATION;
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abort_code = RXGEN_CC_UNMARSHAL;
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if (call->state != AFS_CALL_AWAIT_REPLY)
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abort_code = RXGEN_SS_UNMARSHAL;
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rxrpc_kernel_abort_call(call->rxcall,
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call->state = AFS_CALL_ERROR;
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afs_data_delivered(skb);
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case RXRPC_SKB_MARK_FINAL_ACK:
473
call->state = AFS_CALL_COMPLETE;
475
case RXRPC_SKB_MARK_BUSY:
477
call->error = -EBUSY;
478
call->state = AFS_CALL_BUSY;
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case RXRPC_SKB_MARK_REMOTE_ABORT:
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abort_code = rxrpc_kernel_get_abort_code(skb);
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call->error = call->type->abort_to_error(abort_code);
483
call->state = AFS_CALL_ABORTED;
484
_debug("Rcv ABORT %u -> %d", abort_code, call->error);
486
case RXRPC_SKB_MARK_NET_ERROR:
487
call->error = -rxrpc_kernel_get_error_number(skb);
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call->state = AFS_CALL_ERROR;
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_debug("Rcv NET ERROR %d", call->error);
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case RXRPC_SKB_MARK_LOCAL_ERROR:
492
call->error = -rxrpc_kernel_get_error_number(skb);
493
call->state = AFS_CALL_ERROR;
494
_debug("Rcv LOCAL ERROR %d", call->error);
504
/* make sure the queue is empty if the call is done with (we might have
505
* aborted the call early because of an unmarshalling error) */
506
if (call->state >= AFS_CALL_COMPLETE) {
507
while ((skb = skb_dequeue(&call->rx_queue)))
509
if (call->incoming) {
510
rxrpc_kernel_end_call(call->rxcall);
512
call->type->destructor(call);
521
* wait synchronously for a call to complete
523
static int afs_wait_for_call_to_complete(struct afs_call *call)
528
DECLARE_WAITQUEUE(myself, current);
532
add_wait_queue(&call->waitq, &myself);
534
set_current_state(TASK_INTERRUPTIBLE);
536
/* deliver any messages that are in the queue */
537
if (!skb_queue_empty(&call->rx_queue)) {
538
__set_current_state(TASK_RUNNING);
539
afs_deliver_to_call(call);
544
if (call->state >= AFS_CALL_COMPLETE)
547
if (signal_pending(current))
552
remove_wait_queue(&call->waitq, &myself);
553
__set_current_state(TASK_RUNNING);
556
if (call->state < AFS_CALL_COMPLETE) {
557
_debug("call incomplete");
558
rxrpc_kernel_abort_call(call->rxcall, RX_CALL_DEAD);
559
while ((skb = skb_dequeue(&call->rx_queue)))
563
_debug("call complete");
564
rxrpc_kernel_end_call(call->rxcall);
566
call->type->destructor(call);
568
_leave(" = %d", ret);
573
* wake up a waiting call
575
static void afs_wake_up_call_waiter(struct afs_call *call)
577
wake_up(&call->waitq);
581
* wake up an asynchronous call
583
static void afs_wake_up_async_call(struct afs_call *call)
586
queue_work(afs_async_calls, &call->async_work);
590
* put a call into asynchronous mode
591
* - mustn't touch the call descriptor as the call my have completed by the
594
static int afs_dont_wait_for_call_to_complete(struct afs_call *call)
601
* delete an asynchronous call
603
static void afs_delete_async_call(struct work_struct *work)
605
struct afs_call *call =
606
container_of(work, struct afs_call, async_work);
616
* perform processing on an asynchronous call
617
* - on a multiple-thread workqueue this work item may try to run on several
618
* CPUs at the same time
620
static void afs_process_async_call(struct work_struct *work)
622
struct afs_call *call =
623
container_of(work, struct afs_call, async_work);
627
if (!skb_queue_empty(&call->rx_queue))
628
afs_deliver_to_call(call);
630
if (call->state >= AFS_CALL_COMPLETE && call->wait_mode) {
631
if (call->wait_mode->async_complete)
632
call->wait_mode->async_complete(call->reply,
637
rxrpc_kernel_end_call(call->rxcall);
639
if (call->type->destructor)
640
call->type->destructor(call);
642
/* we can't just delete the call because the work item may be
644
PREPARE_WORK(&call->async_work, afs_delete_async_call);
645
queue_work(afs_async_calls, &call->async_work);
652
* empty a socket buffer into a flat reply buffer
654
void afs_transfer_reply(struct afs_call *call, struct sk_buff *skb)
656
size_t len = skb->len;
658
if (skb_copy_bits(skb, 0, call->buffer + call->reply_size, len) < 0)
660
call->reply_size += len;
664
* accept the backlog of incoming calls
666
static void afs_collect_incoming_call(struct work_struct *work)
668
struct rxrpc_call *rxcall;
669
struct afs_call *call = NULL;
672
while ((skb = skb_dequeue(&afs_incoming_calls))) {
675
/* don't need the notification */
679
call = kzalloc(sizeof(struct afs_call), GFP_KERNEL);
681
rxrpc_kernel_reject_call(afs_socket);
685
INIT_WORK(&call->async_work, afs_process_async_call);
686
call->wait_mode = &afs_async_incoming_call;
687
call->type = &afs_RXCMxxxx;
688
init_waitqueue_head(&call->waitq);
689
skb_queue_head_init(&call->rx_queue);
690
call->state = AFS_CALL_AWAIT_OP_ID;
692
_debug("CALL %p{%s} [%d]",
693
call, call->type->name,
694
atomic_read(&afs_outstanding_calls));
695
atomic_inc(&afs_outstanding_calls);
698
rxcall = rxrpc_kernel_accept_call(afs_socket,
699
(unsigned long) call);
700
if (!IS_ERR(rxcall)) {
701
call->rxcall = rxcall;
711
* grab the operation ID from an incoming cache manager call
713
static int afs_deliver_cm_op_id(struct afs_call *call, struct sk_buff *skb,
716
size_t len = skb->len;
717
void *oibuf = (void *) &call->operation_ID;
719
_enter("{%u},{%zu},%d", call->offset, len, last);
721
ASSERTCMP(call->offset, <, 4);
723
/* the operation ID forms the first four bytes of the request data */
724
len = min_t(size_t, len, 4 - call->offset);
725
if (skb_copy_bits(skb, 0, oibuf + call->offset, len) < 0)
727
if (!pskb_pull(skb, len))
731
if (call->offset < 4) {
733
_leave(" = -EBADMSG [op ID short]");
736
_leave(" = 0 [incomplete]");
740
call->state = AFS_CALL_AWAIT_REQUEST;
742
/* ask the cache manager to route the call (it'll change the call type
744
if (!afs_cm_incoming_call(call))
747
/* pass responsibility for the remainer of this message off to the
748
* cache manager op */
749
return call->type->deliver(call, skb, last);
753
* send an empty reply
755
void afs_send_empty_reply(struct afs_call *call)
762
iov[0].iov_base = NULL;
768
msg.msg_control = NULL;
769
msg.msg_controllen = 0;
772
call->state = AFS_CALL_AWAIT_ACK;
773
switch (rxrpc_kernel_send_data(call->rxcall, &msg, 0)) {
775
_leave(" [replied]");
780
rxrpc_kernel_abort_call(call->rxcall, RX_USER_ABORT);
782
rxrpc_kernel_end_call(call->rxcall);
784
call->type->destructor(call);
792
* send a simple reply
794
void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len)
802
iov[0].iov_base = (void *) buf;
803
iov[0].iov_len = len;
808
msg.msg_control = NULL;
809
msg.msg_controllen = 0;
812
call->state = AFS_CALL_AWAIT_ACK;
813
n = rxrpc_kernel_send_data(call->rxcall, &msg, len);
815
_leave(" [replied]");
820
rxrpc_kernel_abort_call(call->rxcall, RX_USER_ABORT);
822
rxrpc_kernel_end_call(call->rxcall);
824
call->type->destructor(call);
830
* extract a piece of data from the received data socket buffers
832
int afs_extract_data(struct afs_call *call, struct sk_buff *skb,
833
bool last, void *buf, size_t count)
835
size_t len = skb->len;
837
_enter("{%u},{%zu},%d,,%zu", call->offset, len, last, count);
839
ASSERTCMP(call->offset, <, count);
841
len = min_t(size_t, len, count - call->offset);
842
if (skb_copy_bits(skb, 0, buf + call->offset, len) < 0 ||
843
!pskb_pull(skb, len))
847
if (call->offset < count) {
849
_leave(" = -EBADMSG [%d < %zu]", call->offset, count);
852
_leave(" = -EAGAIN");