linux/fs/afs/rxrpc.c
Linus Torvalds 4a55d362ff AFS development
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEqG5UsNXhtOCrfGQP+7dXa6fLC2sFAl3W9UYACgkQ+7dXa6fL
 C2uO1g//T0NvHmrZr6zHbOWlaKkGXRfhgCLENzuTCtcFt29NV+Jv8D/FNuT29d7f
 x8PzrZUBDYfpjP8OSHEivZgU5+a4jpI5pSd2mnGnT3523Oxbm2lIz/SXgpkwQdkM
 4OcK+voCP1MvHbmO7jyOfQm7SX/aOtF90GQrUog5JqwPD0ddSpk/swNNRKZ6xK8/
 cAq9/DHPfYHfLh8wc2FWmhdPA5Px+eKt9kGmMMpwsCulR4yMM7vBCIVNSccSjpYR
 QJzmFpi/TfOiRMc0oZnXLv6UUG+7hHeRfRosoQA8YGGsjwXfs2I7MfAziJx68tfu
 v7beYI+u7tc4EhgK9jXxbgPCJF6nFR/zrbzfC3Zlh7Hr3NCGGzH4gwDu+pn4lwfV
 bpUyA6VwmEt+CVzjj6LB5l4vyRSk+TtVQSwfQvCA7xqvdq0J0/fux6OQ1DwJonQe
 6dOpPUd4ip5tW28S9U7MzbbpMv1kP5hMoAu87gBdygUDhPojM7Ut0mFwZDMOunXg
 vW6oQwKyyFPeJhRcPMKxS7opWQz5889tDe8GPNI/1ociOYCcCkmwZaaG+hYAJ8+N
 8bK2OCi4yNGBa/qMPbwATY+TVKdYcceq/7THxcI3vZk8nVrda73UQHfwUXsjwUzf
 SNNcoMrsEV9BiPSG7gAkCf3VI2gXj+USm3w7SBSjZDM5qR/lRHg=
 =YjAm
 -----END PGP SIGNATURE-----

Merge tag 'afs-next-20191121' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull AFS updates from David Howells:
 "Minor cleanups and fix:

   - Minor fix to make some debugging statements display information
     from the correct iov_iter.

   - Rename some members and variables to make things more obvious or
     consistent.

   - Provide a helper to wrap increments of the usage count on the
     afs_read struct.

   - Use scnprintf() to print into a stack buffer rather than sprintf().

   - Remove some set but unused variables"

* tag 'afs-next-20191121' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Remove set but not used variable 'ret'
  afs: Remove set but not used variables 'before', 'after'
  afs: xattr: use scnprintf
  afs: Introduce an afs_get_read() refcount helper
  afs: Rename desc -> req in afs_fetch_data()
  afs: Switch the naming of call->iter and call->_iter
  afs: Use call->_iter not &call->iter in debugging statements
2019-11-30 10:57:22 -08:00

1022 lines
25 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* Maintain an RxRPC server socket to do AFS communications through
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#include <linux/slab.h>
#include <linux/sched/signal.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include "internal.h"
#include "afs_cm.h"
#include "protocol_yfs.h"
struct workqueue_struct *afs_async_calls;
static void afs_wake_up_call_waiter(struct sock *, struct rxrpc_call *, unsigned long);
static void afs_wake_up_async_call(struct sock *, struct rxrpc_call *, unsigned long);
static void afs_delete_async_call(struct work_struct *);
static void afs_process_async_call(struct work_struct *);
static void afs_rx_new_call(struct sock *, struct rxrpc_call *, unsigned long);
static void afs_rx_discard_new_call(struct rxrpc_call *, unsigned long);
static int afs_deliver_cm_op_id(struct afs_call *);
/* asynchronous incoming call initial processing */
static const struct afs_call_type afs_RXCMxxxx = {
.name = "CB.xxxx",
.deliver = afs_deliver_cm_op_id,
};
/*
* open an RxRPC socket and bind it to be a server for callback notifications
* - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT
*/
int afs_open_socket(struct afs_net *net)
{
struct sockaddr_rxrpc srx;
struct socket *socket;
unsigned int min_level;
int ret;
_enter("");
ret = sock_create_kern(net->net, AF_RXRPC, SOCK_DGRAM, PF_INET6, &socket);
if (ret < 0)
goto error_1;
socket->sk->sk_allocation = GFP_NOFS;
/* bind the callback manager's address to make this a server socket */
memset(&srx, 0, sizeof(srx));
srx.srx_family = AF_RXRPC;
srx.srx_service = CM_SERVICE;
srx.transport_type = SOCK_DGRAM;
srx.transport_len = sizeof(srx.transport.sin6);
srx.transport.sin6.sin6_family = AF_INET6;
srx.transport.sin6.sin6_port = htons(AFS_CM_PORT);
min_level = RXRPC_SECURITY_ENCRYPT;
ret = kernel_setsockopt(socket, SOL_RXRPC, RXRPC_MIN_SECURITY_LEVEL,
(void *)&min_level, sizeof(min_level));
if (ret < 0)
goto error_2;
ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx));
if (ret == -EADDRINUSE) {
srx.transport.sin6.sin6_port = 0;
ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx));
}
if (ret < 0)
goto error_2;
srx.srx_service = YFS_CM_SERVICE;
ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx));
if (ret < 0)
goto error_2;
/* Ideally, we'd turn on service upgrade here, but we can't because
* OpenAFS is buggy and leaks the userStatus field from packet to
* packet and between FS packets and CB packets - so if we try to do an
* upgrade on an FS packet, OpenAFS will leak that into the CB packet
* it sends back to us.
*/
rxrpc_kernel_new_call_notification(socket, afs_rx_new_call,
afs_rx_discard_new_call);
ret = kernel_listen(socket, INT_MAX);
if (ret < 0)
goto error_2;
net->socket = socket;
afs_charge_preallocation(&net->charge_preallocation_work);
_leave(" = 0");
return 0;
error_2:
sock_release(socket);
error_1:
_leave(" = %d", ret);
return ret;
}
/*
* close the RxRPC socket AFS was using
*/
void afs_close_socket(struct afs_net *net)
{
_enter("");
kernel_listen(net->socket, 0);
flush_workqueue(afs_async_calls);
if (net->spare_incoming_call) {
afs_put_call(net->spare_incoming_call);
net->spare_incoming_call = NULL;
}
_debug("outstanding %u", atomic_read(&net->nr_outstanding_calls));
wait_var_event(&net->nr_outstanding_calls,
!atomic_read(&net->nr_outstanding_calls));
_debug("no outstanding calls");
kernel_sock_shutdown(net->socket, SHUT_RDWR);
flush_workqueue(afs_async_calls);
sock_release(net->socket);
_debug("dework");
_leave("");
}
/*
* Allocate a call.
*/
static struct afs_call *afs_alloc_call(struct afs_net *net,
const struct afs_call_type *type,
gfp_t gfp)
{
struct afs_call *call;
int o;
call = kzalloc(sizeof(*call), gfp);
if (!call)
return NULL;
call->type = type;
call->net = net;
call->debug_id = atomic_inc_return(&rxrpc_debug_id);
atomic_set(&call->usage, 1);
INIT_WORK(&call->async_work, afs_process_async_call);
init_waitqueue_head(&call->waitq);
spin_lock_init(&call->state_lock);
call->iter = &call->def_iter;
o = atomic_inc_return(&net->nr_outstanding_calls);
trace_afs_call(call, afs_call_trace_alloc, 1, o,
__builtin_return_address(0));
return call;
}
/*
* Dispose of a reference on a call.
*/
void afs_put_call(struct afs_call *call)
{
struct afs_net *net = call->net;
int n = atomic_dec_return(&call->usage);
int o = atomic_read(&net->nr_outstanding_calls);
trace_afs_call(call, afs_call_trace_put, n + 1, o,
__builtin_return_address(0));
ASSERTCMP(n, >=, 0);
if (n == 0) {
ASSERT(!work_pending(&call->async_work));
ASSERT(call->type->name != NULL);
if (call->rxcall) {
rxrpc_kernel_end_call(net->socket, call->rxcall);
call->rxcall = NULL;
}
if (call->type->destructor)
call->type->destructor(call);
afs_put_server(call->net, call->server, afs_server_trace_put_call);
afs_put_cb_interest(call->net, call->cbi);
afs_put_addrlist(call->alist);
kfree(call->request);
trace_afs_call(call, afs_call_trace_free, 0, o,
__builtin_return_address(0));
kfree(call);
o = atomic_dec_return(&net->nr_outstanding_calls);
if (o == 0)
wake_up_var(&net->nr_outstanding_calls);
}
}
static struct afs_call *afs_get_call(struct afs_call *call,
enum afs_call_trace why)
{
int u = atomic_inc_return(&call->usage);
trace_afs_call(call, why, u,
atomic_read(&call->net->nr_outstanding_calls),
__builtin_return_address(0));
return call;
}
/*
* Queue the call for actual work.
*/
static void afs_queue_call_work(struct afs_call *call)
{
if (call->type->work) {
INIT_WORK(&call->work, call->type->work);
afs_get_call(call, afs_call_trace_work);
if (!queue_work(afs_wq, &call->work))
afs_put_call(call);
}
}
/*
* allocate a call with flat request and reply buffers
*/
struct afs_call *afs_alloc_flat_call(struct afs_net *net,
const struct afs_call_type *type,
size_t request_size, size_t reply_max)
{
struct afs_call *call;
call = afs_alloc_call(net, type, GFP_NOFS);
if (!call)
goto nomem_call;
if (request_size) {
call->request_size = request_size;
call->request = kmalloc(request_size, GFP_NOFS);
if (!call->request)
goto nomem_free;
}
if (reply_max) {
call->reply_max = reply_max;
call->buffer = kmalloc(reply_max, GFP_NOFS);
if (!call->buffer)
goto nomem_free;
}
afs_extract_to_buf(call, call->reply_max);
call->operation_ID = type->op;
init_waitqueue_head(&call->waitq);
return call;
nomem_free:
afs_put_call(call);
nomem_call:
return NULL;
}
/*
* clean up a call with flat buffer
*/
void afs_flat_call_destructor(struct afs_call *call)
{
_enter("");
kfree(call->request);
call->request = NULL;
kfree(call->buffer);
call->buffer = NULL;
}
#define AFS_BVEC_MAX 8
/*
* Load the given bvec with the next few pages.
*/
static void afs_load_bvec(struct afs_call *call, struct msghdr *msg,
struct bio_vec *bv, pgoff_t first, pgoff_t last,
unsigned offset)
{
struct page *pages[AFS_BVEC_MAX];
unsigned int nr, n, i, to, bytes = 0;
nr = min_t(pgoff_t, last - first + 1, AFS_BVEC_MAX);
n = find_get_pages_contig(call->mapping, first, nr, pages);
ASSERTCMP(n, ==, nr);
msg->msg_flags |= MSG_MORE;
for (i = 0; i < nr; i++) {
to = PAGE_SIZE;
if (first + i >= last) {
to = call->last_to;
msg->msg_flags &= ~MSG_MORE;
}
bv[i].bv_page = pages[i];
bv[i].bv_len = to - offset;
bv[i].bv_offset = offset;
bytes += to - offset;
offset = 0;
}
iov_iter_bvec(&msg->msg_iter, WRITE, bv, nr, bytes);
}
/*
* Advance the AFS call state when the RxRPC call ends the transmit phase.
*/
static void afs_notify_end_request_tx(struct sock *sock,
struct rxrpc_call *rxcall,
unsigned long call_user_ID)
{
struct afs_call *call = (struct afs_call *)call_user_ID;
afs_set_call_state(call, AFS_CALL_CL_REQUESTING, AFS_CALL_CL_AWAIT_REPLY);
}
/*
* attach the data from a bunch of pages on an inode to a call
*/
static int afs_send_pages(struct afs_call *call, struct msghdr *msg)
{
struct bio_vec bv[AFS_BVEC_MAX];
unsigned int bytes, nr, loop, offset;
pgoff_t first = call->first, last = call->last;
int ret;
offset = call->first_offset;
call->first_offset = 0;
do {
afs_load_bvec(call, msg, bv, first, last, offset);
trace_afs_send_pages(call, msg, first, last, offset);
offset = 0;
bytes = msg->msg_iter.count;
nr = msg->msg_iter.nr_segs;
ret = rxrpc_kernel_send_data(call->net->socket, call->rxcall, msg,
bytes, afs_notify_end_request_tx);
for (loop = 0; loop < nr; loop++)
put_page(bv[loop].bv_page);
if (ret < 0)
break;
first += nr;
} while (first <= last);
trace_afs_sent_pages(call, call->first, last, first, ret);
return ret;
}
/*
* Initiate a call and synchronously queue up the parameters for dispatch. Any
* error is stored into the call struct, which the caller must check for.
*/
void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp)
{
struct sockaddr_rxrpc *srx = &ac->alist->addrs[ac->index];
struct rxrpc_call *rxcall;
struct msghdr msg;
struct kvec iov[1];
s64 tx_total_len;
int ret;
_enter(",{%pISp},", &srx->transport);
ASSERT(call->type != NULL);
ASSERT(call->type->name != NULL);
_debug("____MAKE %p{%s,%x} [%d]____",
call, call->type->name, key_serial(call->key),
atomic_read(&call->net->nr_outstanding_calls));
call->addr_ix = ac->index;
call->alist = afs_get_addrlist(ac->alist);
/* Work out the length we're going to transmit. This is awkward for
* calls such as FS.StoreData where there's an extra injection of data
* after the initial fixed part.
*/
tx_total_len = call->request_size;
if (call->send_pages) {
if (call->last == call->first) {
tx_total_len += call->last_to - call->first_offset;
} else {
/* It looks mathematically like you should be able to
* combine the following lines with the ones above, but
* unsigned arithmetic is fun when it wraps...
*/
tx_total_len += PAGE_SIZE - call->first_offset;
tx_total_len += call->last_to;
tx_total_len += (call->last - call->first - 1) * PAGE_SIZE;
}
}
/* If the call is going to be asynchronous, we need an extra ref for
* the call to hold itself so the caller need not hang on to its ref.
*/
if (call->async)
afs_get_call(call, afs_call_trace_get);
/* create a call */
rxcall = rxrpc_kernel_begin_call(call->net->socket, srx, call->key,
(unsigned long)call,
tx_total_len, gfp,
(call->async ?
afs_wake_up_async_call :
afs_wake_up_call_waiter),
call->upgrade,
call->intr,
call->debug_id);
if (IS_ERR(rxcall)) {
ret = PTR_ERR(rxcall);
call->error = ret;
goto error_kill_call;
}
call->rxcall = rxcall;
if (call->max_lifespan)
rxrpc_kernel_set_max_life(call->net->socket, rxcall,
call->max_lifespan);
/* send the request */
iov[0].iov_base = call->request;
iov[0].iov_len = call->request_size;
msg.msg_name = NULL;
msg.msg_namelen = 0;
iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, call->request_size);
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_flags = MSG_WAITALL | (call->send_pages ? MSG_MORE : 0);
ret = rxrpc_kernel_send_data(call->net->socket, rxcall,
&msg, call->request_size,
afs_notify_end_request_tx);
if (ret < 0)
goto error_do_abort;
if (call->send_pages) {
ret = afs_send_pages(call, &msg);
if (ret < 0)
goto error_do_abort;
}
/* Note that at this point, we may have received the reply or an abort
* - and an asynchronous call may already have completed.
*
* afs_wait_for_call_to_complete(call, ac)
* must be called to synchronously clean up.
*/
return;
error_do_abort:
if (ret != -ECONNABORTED) {
rxrpc_kernel_abort_call(call->net->socket, rxcall,
RX_USER_ABORT, ret, "KSD");
} else {
iov_iter_kvec(&msg.msg_iter, READ, NULL, 0, 0);
rxrpc_kernel_recv_data(call->net->socket, rxcall,
&msg.msg_iter, false,
&call->abort_code, &call->service_id);
ac->abort_code = call->abort_code;
ac->responded = true;
}
call->error = ret;
trace_afs_call_done(call);
error_kill_call:
if (call->type->done)
call->type->done(call);
/* We need to dispose of the extra ref we grabbed for an async call.
* The call, however, might be queued on afs_async_calls and we need to
* make sure we don't get any more notifications that might requeue it.
*/
if (call->rxcall) {
rxrpc_kernel_end_call(call->net->socket, call->rxcall);
call->rxcall = NULL;
}
if (call->async) {
if (cancel_work_sync(&call->async_work))
afs_put_call(call);
afs_put_call(call);
}
ac->error = ret;
call->state = AFS_CALL_COMPLETE;
_leave(" = %d", ret);
}
/*
* deliver messages to a call
*/
static void afs_deliver_to_call(struct afs_call *call)
{
enum afs_call_state state;
u32 abort_code, remote_abort = 0;
int ret;
_enter("%s", call->type->name);
while (state = READ_ONCE(call->state),
state == AFS_CALL_CL_AWAIT_REPLY ||
state == AFS_CALL_SV_AWAIT_OP_ID ||
state == AFS_CALL_SV_AWAIT_REQUEST ||
state == AFS_CALL_SV_AWAIT_ACK
) {
if (state == AFS_CALL_SV_AWAIT_ACK) {
iov_iter_kvec(&call->def_iter, READ, NULL, 0, 0);
ret = rxrpc_kernel_recv_data(call->net->socket,
call->rxcall, &call->def_iter,
false, &remote_abort,
&call->service_id);
trace_afs_receive_data(call, &call->def_iter, false, ret);
if (ret == -EINPROGRESS || ret == -EAGAIN)
return;
if (ret < 0 || ret == 1) {
if (ret == 1)
ret = 0;
goto call_complete;
}
return;
}
if (!call->have_reply_time &&
rxrpc_kernel_get_reply_time(call->net->socket,
call->rxcall,
&call->reply_time))
call->have_reply_time = true;
ret = call->type->deliver(call);
state = READ_ONCE(call->state);
switch (ret) {
case 0:
afs_queue_call_work(call);
if (state == AFS_CALL_CL_PROC_REPLY) {
if (call->cbi)
set_bit(AFS_SERVER_FL_MAY_HAVE_CB,
&call->cbi->server->flags);
goto call_complete;
}
ASSERTCMP(state, >, AFS_CALL_CL_PROC_REPLY);
goto done;
case -EINPROGRESS:
case -EAGAIN:
goto out;
case -ECONNABORTED:
ASSERTCMP(state, ==, AFS_CALL_COMPLETE);
goto done;
case -ENOTSUPP:
abort_code = RXGEN_OPCODE;
rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
abort_code, ret, "KIV");
goto local_abort;
case -EIO:
pr_err("kAFS: Call %u in bad state %u\n",
call->debug_id, state);
/* Fall through */
case -ENODATA:
case -EBADMSG:
case -EMSGSIZE:
abort_code = RXGEN_CC_UNMARSHAL;
if (state != AFS_CALL_CL_AWAIT_REPLY)
abort_code = RXGEN_SS_UNMARSHAL;
rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
abort_code, ret, "KUM");
goto local_abort;
default:
abort_code = RX_USER_ABORT;
rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
abort_code, ret, "KER");
goto local_abort;
}
}
done:
if (call->type->done)
call->type->done(call);
if (state == AFS_CALL_COMPLETE && call->incoming)
afs_put_call(call);
out:
_leave("");
return;
local_abort:
abort_code = 0;
call_complete:
afs_set_call_complete(call, ret, remote_abort);
state = AFS_CALL_COMPLETE;
goto done;
}
/*
* Wait synchronously for a call to complete and clean up the call struct.
*/
long afs_wait_for_call_to_complete(struct afs_call *call,
struct afs_addr_cursor *ac)
{
signed long rtt2, timeout;
long ret;
bool stalled = false;
u64 rtt;
u32 life, last_life;
bool rxrpc_complete = false;
DECLARE_WAITQUEUE(myself, current);
_enter("");
ret = call->error;
if (ret < 0)
goto out;
rtt = rxrpc_kernel_get_rtt(call->net->socket, call->rxcall);
rtt2 = nsecs_to_jiffies64(rtt) * 2;
if (rtt2 < 2)
rtt2 = 2;
timeout = rtt2;
rxrpc_kernel_check_life(call->net->socket, call->rxcall, &last_life);
add_wait_queue(&call->waitq, &myself);
for (;;) {
set_current_state(TASK_UNINTERRUPTIBLE);
/* deliver any messages that are in the queue */
if (!afs_check_call_state(call, AFS_CALL_COMPLETE) &&
call->need_attention) {
call->need_attention = false;
__set_current_state(TASK_RUNNING);
afs_deliver_to_call(call);
timeout = rtt2;
continue;
}
if (afs_check_call_state(call, AFS_CALL_COMPLETE))
break;
if (!rxrpc_kernel_check_life(call->net->socket, call->rxcall, &life)) {
/* rxrpc terminated the call. */
rxrpc_complete = true;
break;
}
if (call->intr && timeout == 0 &&
life == last_life && signal_pending(current)) {
if (stalled)
break;
__set_current_state(TASK_RUNNING);
rxrpc_kernel_probe_life(call->net->socket, call->rxcall);
timeout = rtt2;
stalled = true;
continue;
}
if (life != last_life) {
timeout = rtt2;
last_life = life;
stalled = false;
}
timeout = schedule_timeout(timeout);
}
remove_wait_queue(&call->waitq, &myself);
__set_current_state(TASK_RUNNING);
if (!afs_check_call_state(call, AFS_CALL_COMPLETE)) {
if (rxrpc_complete) {
afs_set_call_complete(call, call->error, call->abort_code);
} else {
/* Kill off the call if it's still live. */
_debug("call interrupted");
if (rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
RX_USER_ABORT, -EINTR, "KWI"))
afs_set_call_complete(call, -EINTR, 0);
}
}
spin_lock_bh(&call->state_lock);
ac->abort_code = call->abort_code;
ac->error = call->error;
spin_unlock_bh(&call->state_lock);
ret = ac->error;
switch (ret) {
case 0:
ret = call->ret0;
call->ret0 = 0;
/* Fall through */
case -ECONNABORTED:
ac->responded = true;
break;
}
out:
_debug("call complete");
afs_put_call(call);
_leave(" = %p", (void *)ret);
return ret;
}
/*
* wake up a waiting call
*/
static void afs_wake_up_call_waiter(struct sock *sk, struct rxrpc_call *rxcall,
unsigned long call_user_ID)
{
struct afs_call *call = (struct afs_call *)call_user_ID;
call->need_attention = true;
wake_up(&call->waitq);
}
/*
* wake up an asynchronous call
*/
static void afs_wake_up_async_call(struct sock *sk, struct rxrpc_call *rxcall,
unsigned long call_user_ID)
{
struct afs_call *call = (struct afs_call *)call_user_ID;
int u;
trace_afs_notify_call(rxcall, call);
call->need_attention = true;
u = atomic_fetch_add_unless(&call->usage, 1, 0);
if (u != 0) {
trace_afs_call(call, afs_call_trace_wake, u,
atomic_read(&call->net->nr_outstanding_calls),
__builtin_return_address(0));
if (!queue_work(afs_async_calls, &call->async_work))
afs_put_call(call);
}
}
/*
* Delete an asynchronous call. The work item carries a ref to the call struct
* that we need to release.
*/
static void afs_delete_async_call(struct work_struct *work)
{
struct afs_call *call = container_of(work, struct afs_call, async_work);
_enter("");
afs_put_call(call);
_leave("");
}
/*
* Perform I/O processing on an asynchronous call. The work item carries a ref
* to the call struct that we either need to release or to pass on.
*/
static void afs_process_async_call(struct work_struct *work)
{
struct afs_call *call = container_of(work, struct afs_call, async_work);
_enter("");
if (call->state < AFS_CALL_COMPLETE && call->need_attention) {
call->need_attention = false;
afs_deliver_to_call(call);
}
if (call->state == AFS_CALL_COMPLETE) {
/* We have two refs to release - one from the alloc and one
* queued with the work item - and we can't just deallocate the
* call because the work item may be queued again.
*/
call->async_work.func = afs_delete_async_call;
if (!queue_work(afs_async_calls, &call->async_work))
afs_put_call(call);
}
afs_put_call(call);
_leave("");
}
static void afs_rx_attach(struct rxrpc_call *rxcall, unsigned long user_call_ID)
{
struct afs_call *call = (struct afs_call *)user_call_ID;
call->rxcall = rxcall;
}
/*
* Charge the incoming call preallocation.
*/
void afs_charge_preallocation(struct work_struct *work)
{
struct afs_net *net =
container_of(work, struct afs_net, charge_preallocation_work);
struct afs_call *call = net->spare_incoming_call;
for (;;) {
if (!call) {
call = afs_alloc_call(net, &afs_RXCMxxxx, GFP_KERNEL);
if (!call)
break;
call->async = true;
call->state = AFS_CALL_SV_AWAIT_OP_ID;
init_waitqueue_head(&call->waitq);
afs_extract_to_tmp(call);
}
if (rxrpc_kernel_charge_accept(net->socket,
afs_wake_up_async_call,
afs_rx_attach,
(unsigned long)call,
GFP_KERNEL,
call->debug_id) < 0)
break;
call = NULL;
}
net->spare_incoming_call = call;
}
/*
* Discard a preallocated call when a socket is shut down.
*/
static void afs_rx_discard_new_call(struct rxrpc_call *rxcall,
unsigned long user_call_ID)
{
struct afs_call *call = (struct afs_call *)user_call_ID;
call->rxcall = NULL;
afs_put_call(call);
}
/*
* Notification of an incoming call.
*/
static void afs_rx_new_call(struct sock *sk, struct rxrpc_call *rxcall,
unsigned long user_call_ID)
{
struct afs_net *net = afs_sock2net(sk);
queue_work(afs_wq, &net->charge_preallocation_work);
}
/*
* Grab the operation ID from an incoming cache manager call. The socket
* buffer is discarded on error or if we don't yet have sufficient data.
*/
static int afs_deliver_cm_op_id(struct afs_call *call)
{
int ret;
_enter("{%zu}", iov_iter_count(call->iter));
/* the operation ID forms the first four bytes of the request data */
ret = afs_extract_data(call, true);
if (ret < 0)
return ret;
call->operation_ID = ntohl(call->tmp);
afs_set_call_state(call, AFS_CALL_SV_AWAIT_OP_ID, AFS_CALL_SV_AWAIT_REQUEST);
/* ask the cache manager to route the call (it'll change the call type
* if successful) */
if (!afs_cm_incoming_call(call))
return -ENOTSUPP;
trace_afs_cb_call(call);
/* pass responsibility for the remainer of this message off to the
* cache manager op */
return call->type->deliver(call);
}
/*
* Advance the AFS call state when an RxRPC service call ends the transmit
* phase.
*/
static void afs_notify_end_reply_tx(struct sock *sock,
struct rxrpc_call *rxcall,
unsigned long call_user_ID)
{
struct afs_call *call = (struct afs_call *)call_user_ID;
afs_set_call_state(call, AFS_CALL_SV_REPLYING, AFS_CALL_SV_AWAIT_ACK);
}
/*
* send an empty reply
*/
void afs_send_empty_reply(struct afs_call *call)
{
struct afs_net *net = call->net;
struct msghdr msg;
_enter("");
rxrpc_kernel_set_tx_length(net->socket, call->rxcall, 0);
msg.msg_name = NULL;
msg.msg_namelen = 0;
iov_iter_kvec(&msg.msg_iter, WRITE, NULL, 0, 0);
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_flags = 0;
switch (rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, 0,
afs_notify_end_reply_tx)) {
case 0:
_leave(" [replied]");
return;
case -ENOMEM:
_debug("oom");
rxrpc_kernel_abort_call(net->socket, call->rxcall,
RX_USER_ABORT, -ENOMEM, "KOO");
/* Fall through */
default:
_leave(" [error]");
return;
}
}
/*
* send a simple reply
*/
void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len)
{
struct afs_net *net = call->net;
struct msghdr msg;
struct kvec iov[1];
int n;
_enter("");
rxrpc_kernel_set_tx_length(net->socket, call->rxcall, len);
iov[0].iov_base = (void *) buf;
iov[0].iov_len = len;
msg.msg_name = NULL;
msg.msg_namelen = 0;
iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, len);
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_flags = 0;
n = rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, len,
afs_notify_end_reply_tx);
if (n >= 0) {
/* Success */
_leave(" [replied]");
return;
}
if (n == -ENOMEM) {
_debug("oom");
rxrpc_kernel_abort_call(net->socket, call->rxcall,
RX_USER_ABORT, -ENOMEM, "KOO");
}
_leave(" [error]");
}
/*
* Extract a piece of data from the received data socket buffers.
*/
int afs_extract_data(struct afs_call *call, bool want_more)
{
struct afs_net *net = call->net;
struct iov_iter *iter = call->iter;
enum afs_call_state state;
u32 remote_abort = 0;
int ret;
_enter("{%s,%zu},%d", call->type->name, iov_iter_count(iter), want_more);
ret = rxrpc_kernel_recv_data(net->socket, call->rxcall, iter,
want_more, &remote_abort,
&call->service_id);
if (ret == 0 || ret == -EAGAIN)
return ret;
state = READ_ONCE(call->state);
if (ret == 1) {
switch (state) {
case AFS_CALL_CL_AWAIT_REPLY:
afs_set_call_state(call, state, AFS_CALL_CL_PROC_REPLY);
break;
case AFS_CALL_SV_AWAIT_REQUEST:
afs_set_call_state(call, state, AFS_CALL_SV_REPLYING);
break;
case AFS_CALL_COMPLETE:
kdebug("prem complete %d", call->error);
return afs_io_error(call, afs_io_error_extract);
default:
break;
}
return 0;
}
afs_set_call_complete(call, ret, remote_abort);
return ret;
}
/*
* Log protocol error production.
*/
noinline int afs_protocol_error(struct afs_call *call, int error,
enum afs_eproto_cause cause)
{
trace_afs_protocol_error(call, error, cause);
return error;
}