diff options
Diffstat (limited to 'fs/afs/rxrpc.c')
| -rw-r--r-- | fs/afs/rxrpc.c | 951 |
1 files changed, 951 insertions, 0 deletions
diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c new file mode 100644 index 000000000..5d6d4f9f0 --- /dev/null +++ b/fs/afs/rxrpc.c @@ -0,0 +1,951 @@ +/* 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) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#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" + +struct workqueue_struct *afs_async_calls; + +static void afs_wake_up_call_waiter(struct sock *, struct rxrpc_call *, unsigned long); +static long afs_wait_for_call_to_complete(struct afs_call *, struct afs_addr_cursor *); +static void afs_wake_up_async_call(struct sock *, struct rxrpc_call *, unsigned long); +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; + + 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); + + 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, 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->cm_server); + afs_put_cb_interest(call->net, call->cbi); + 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); + } +} + +/* + * Queue the call for actual work. Returns 0 unconditionally for convenience. + */ +int afs_queue_call_work(struct afs_call *call) +{ + int u = atomic_inc_return(&call->usage); + + trace_afs_call(call, afs_call_trace_work, u, + atomic_read(&call->net->nr_outstanding_calls), + __builtin_return_address(0)); + + INIT_WORK(&call->work, call->type->work); + + if (!queue_work(afs_wq, &call->work)) + afs_put_call(call); + return 0; +} + +/* + * 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; + } + + 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 | ITER_BVEC, 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 + */ +long afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, + gfp_t gfp, bool async) +{ + struct sockaddr_rxrpc *srx = ac->addr; + 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->async = async; + + /* 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; + } + } + + /* create a call */ + rxcall = rxrpc_kernel_begin_call(call->net->socket, srx, call->key, + (unsigned long)call, + tx_total_len, gfp, + (async ? + afs_wake_up_async_call : + afs_wake_up_call_waiter), + call->upgrade, + call->debug_id); + if (IS_ERR(rxcall)) { + ret = PTR_ERR(rxcall); + goto error_kill_call; + } + + call->rxcall = rxcall; + + /* 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 | ITER_KVEC, 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; + } + + /* at this point, an async call may no longer exist as it may have + * already completed */ + if (call->async) + return -EINPROGRESS; + + return afs_wait_for_call_to_complete(call, ac); + +error_do_abort: + call->state = AFS_CALL_COMPLETE; + if (ret != -ECONNABORTED) { + rxrpc_kernel_abort_call(call->net->socket, rxcall, + RX_USER_ABORT, ret, "KSD"); + } else { + iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, 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: + afs_put_call(call); + ac->error = ret; + _leave(" = %d", ret); + return 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) { + struct iov_iter iter; + + iov_iter_kvec(&iter, READ | ITER_KVEC, NULL, 0, 0); + ret = rxrpc_kernel_recv_data(call->net->socket, + call->rxcall, &iter, false, + &remote_abort, + &call->service_id); + trace_afs_recv_data(call, 0, 0, false, ret); + + if (ret == -EINPROGRESS || ret == -EAGAIN) + return; + if (ret < 0 || ret == 1) { + if (ret == 1) + ret = 0; + goto call_complete; + } + return; + } + + ret = call->type->deliver(call); + state = READ_ONCE(call->state); + switch (ret) { + case 0: + 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: + default: + 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, -EBADMSG, "KUM"); + goto local_abort; + } + } + +done: + 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 + */ +static long afs_wait_for_call_to_complete(struct afs_call *call, + struct afs_addr_cursor *ac) +{ + signed long rtt2, timeout; + long ret; + u64 rtt; + u32 life, last_life; + + DECLARE_WAITQUEUE(myself, current); + + _enter(""); + + rtt = rxrpc_kernel_get_rtt(call->net->socket, call->rxcall); + rtt2 = nsecs_to_jiffies64(rtt) * 2; + if (rtt2 < 2) + rtt2 = 2; + + timeout = rtt2; + last_life = rxrpc_kernel_check_life(call->net->socket, call->rxcall); + + 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; + + life = rxrpc_kernel_check_life(call->net->socket, call->rxcall); + if (timeout == 0 && + life == last_life && signal_pending(current)) + break; + + if (life != last_life) { + timeout = rtt2; + last_life = life; + } + + timeout = schedule_timeout(timeout); + } + + remove_wait_queue(&call->waitq, &myself); + __set_current_state(TASK_RUNNING); + + /* Kill off the call if it's still live. */ + if (!afs_check_call_state(call, AFS_CALL_COMPLETE)) { + _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: + if (call->ret_reply0) { + ret = (long)call->reply[0]; + call->reply[0] = NULL; + } + /* Fall through */ + case -ECONNABORTED: + ac->responded = true; + break; + } + + _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 + 1, + 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); + } + + 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}", call->offset); + + ASSERTCMP(call->offset, <, 4); + + /* the operation ID forms the first four bytes of the request data */ + ret = afs_extract_data(call, &call->tmp, 4, 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); + call->offset = 0; + + /* 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 | ITER_KVEC, 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"); + 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 | ITER_KVEC, 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, void *buf, size_t count, + bool want_more) +{ + struct afs_net *net = call->net; + struct iov_iter iter; + struct kvec iov; + enum afs_call_state state; + u32 remote_abort = 0; + int ret; + + _enter("{%s,%zu},,%zu,%d", + call->type->name, call->offset, count, want_more); + + ASSERTCMP(call->offset, <=, count); + + iov.iov_base = buf + call->offset; + iov.iov_len = count - call->offset; + iov_iter_kvec(&iter, ITER_KVEC | READ, &iov, 1, count - call->offset); + + ret = rxrpc_kernel_recv_data(net->socket, call->rxcall, &iter, + want_more, &remote_abort, + &call->service_id); + call->offset += (count - call->offset) - iov_iter_count(&iter); + trace_afs_recv_data(call, count, call->offset, want_more, ret); + 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 -EIO; + 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) +{ + trace_afs_protocol_error(call, error, __builtin_return_address(0)); + return error; +} |