korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-30 14:34:51 +08:00
Code Issues Packages Projects Releases Wiki Activity
904632a224
linux/net/rxrpc/recvmsg.c
David Howells 8c3e34a4ff rxrpc: Rename files matching ar-*.c to git rid of the "ar-" prefix 
Rename files matching net/rxrpc/ar-*.c to get rid of the "ar-" prefix.
This will aid splitting those files by making easier to come up with new
names.

Note that the not all files are simply renamed from ar-X.c to X.c.  The
following exceptions are made:

 (*) ar-call.c -> call_object.c
     ar-ack.c -> call_event.c

     call_object.c is going to contain the core of the call object
     handling.  Call event handling is all going to be in call_event.c.

 (*) ar-accept.c -> call_accept.c

     Incoming call handling is going to be here.

 (*) ar-connection.c -> conn_object.c
     ar-connevent.c -> conn_event.c

     The former file is going to have the basic connection object handling,
     but there will likely be some differentiation between client
     connections and service connections in additional files later.  The
     latter file will have all the connection-level event handling.

 (*) ar-local.c -> local_object.c

     This will have the local endpoint object handling code.  The local
     endpoint event handling code will later be split out into
     local_event.c.

 (*) ar-peer.c -> peer_object.c

     This will have the peer endpoint object handling code.  Peer event
     handling code will be placed in peer_event.c (for the moment, there is
     none).

 (*) ar-error.c -> peer_event.c

     This will become the peer event handling code, though for the moment
     it's actually driven from the local endpoint's perspective.

Note that I haven't renamed ar-transport.c to transport_object.c as the
intention is to delete it when the rxrpc_transport struct is excised.

The only file that actually has its contents changed is net/rxrpc/Makefile.

net/rxrpc/ar-internal.h will need its section marker comments updating, but
I'll do that in a separate patch to make it easier for git to follow the
history across the rename.  I may also want to rename ar-internal.h at some
point - but that would mean updating all the #includes and I'd rather do
that in a separate step.

Signed-off-by: David Howells <dhowells@redhat.com.
2016-06-13 12:16:05 +01:00

437 lines
11 KiB
C
Raw Blame History

/* RxRPC recvmsg() implementation
*
* 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.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/export.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include "ar-internal.h"
/*
* removal a call's user ID from the socket tree to make the user ID available
* again and so that it won't be seen again in association with that call
*/
void rxrpc_remove_user_ID(struct rxrpc_sock *rx, struct rxrpc_call *call)
{
_debug("RELEASE CALL %d", call->debug_id);
if (test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
write_lock_bh(&rx->call_lock);
rb_erase(&call->sock_node, &call->socket->calls);
clear_bit(RXRPC_CALL_HAS_USERID, &call->flags);
write_unlock_bh(&rx->call_lock);
}
read_lock_bh(&call->state_lock);
if (!test_bit(RXRPC_CALL_RELEASED, &call->flags) &&
!test_and_set_bit(RXRPC_CALL_EV_RELEASE, &call->events))
rxrpc_queue_call(call);
read_unlock_bh(&call->state_lock);
}
/*
* receive a message from an RxRPC socket
* - we need to be careful about two or more threads calling recvmsg
* simultaneously
*/
int rxrpc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
int flags)
{
struct rxrpc_skb_priv *sp;
struct rxrpc_call *call = NULL, *continue_call = NULL;
struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
struct sk_buff *skb;
long timeo;
int copy, ret, ullen, offset, copied = 0;
u32 abort_code;
DEFINE_WAIT(wait);
_enter(",,,%zu,%d", len, flags);
if (flags & (MSG_OOB | MSG_TRUNC))
return -EOPNOTSUPP;
ullen = msg->msg_flags & MSG_CMSG_COMPAT ? 4 : sizeof(unsigned long);
timeo = sock_rcvtimeo(&rx->sk, flags & MSG_DONTWAIT);
msg->msg_flags |= MSG_MORE;
lock_sock(&rx->sk);
for (;;) {
/* return immediately if a client socket has no outstanding
* calls */
if (RB_EMPTY_ROOT(&rx->calls)) {
if (copied)
goto out;
if (rx->sk.sk_state != RXRPC_SERVER_LISTENING) {
release_sock(&rx->sk);
if (continue_call)
rxrpc_put_call(continue_call);
return -ENODATA;
}
}
/* get the next message on the Rx queue */
skb = skb_peek(&rx->sk.sk_receive_queue);
if (!skb) {
/* nothing remains on the queue */
if (copied &&
(flags & MSG_PEEK || timeo == 0))
goto out;
/* wait for a message to turn up */
release_sock(&rx->sk);
prepare_to_wait_exclusive(sk_sleep(&rx->sk), &wait,
TASK_INTERRUPTIBLE);
ret = sock_error(&rx->sk);
if (ret)
goto wait_error;
if (skb_queue_empty(&rx->sk.sk_receive_queue)) {
if (signal_pending(current))
goto wait_interrupted;
timeo = schedule_timeout(timeo);
}
finish_wait(sk_sleep(&rx->sk), &wait);
lock_sock(&rx->sk);
continue;
}
peek_next_packet:
sp = rxrpc_skb(skb);
call = sp->call;
ASSERT(call != NULL);
_debug("next pkt %s", rxrpc_pkts[sp->hdr.type]);
/* make sure we wait for the state to be updated in this call */
spin_lock_bh(&call->lock);
spin_unlock_bh(&call->lock);
if (test_bit(RXRPC_CALL_RELEASED, &call->flags)) {
_debug("packet from released call");
if (skb_dequeue(&rx->sk.sk_receive_queue) != skb)
BUG();
rxrpc_free_skb(skb);
continue;
}
/* determine whether to continue last data receive */
if (continue_call) {
_debug("maybe cont");
if (call != continue_call ||
skb->mark != RXRPC_SKB_MARK_DATA) {
release_sock(&rx->sk);
rxrpc_put_call(continue_call);
_leave(" = %d [noncont]", copied);
return copied;
}
}
rxrpc_get_call(call);
/* copy the peer address and timestamp */
if (!continue_call) {
if (msg->msg_name) {
size_t len =
sizeof(call->conn->trans->peer->srx);
memcpy(msg->msg_name,
&call->conn->trans->peer->srx, len);
msg->msg_namelen = len;
}
sock_recv_timestamp(msg, &rx->sk, skb);
}
/* receive the message */
if (skb->mark != RXRPC_SKB_MARK_DATA)
goto receive_non_data_message;
_debug("recvmsg DATA #%u { %d, %d }",
sp->hdr.seq, skb->len, sp->offset);
if (!continue_call) {
/* only set the control data once per recvmsg() */
ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID,
ullen, &call->user_call_ID);
if (ret < 0)
goto copy_error;
ASSERT(test_bit(RXRPC_CALL_HAS_USERID, &call->flags));
}
ASSERTCMP(sp->hdr.seq, >=, call->rx_data_recv);
ASSERTCMP(sp->hdr.seq, <=, call->rx_data_recv + 1);
call->rx_data_recv = sp->hdr.seq;
ASSERTCMP(sp->hdr.seq, >, call->rx_data_eaten);
offset = sp->offset;
copy = skb->len - offset;
if (copy > len - copied)
copy = len - copied;
ret = skb_copy_datagram_msg(skb, offset, msg, copy);
if (ret < 0)
goto copy_error;
/* handle piecemeal consumption of data packets */
_debug("copied %d+%d", copy, copied);
offset += copy;
copied += copy;
if (!(flags & MSG_PEEK))
sp->offset = offset;
if (sp->offset < skb->len) {
_debug("buffer full");
ASSERTCMP(copied, ==, len);
break;
}
/* we transferred the whole data packet */
if (sp->hdr.flags & RXRPC_LAST_PACKET) {
_debug("last");
if (call->conn->out_clientflag) {
/* last byte of reply received */
ret = copied;
goto terminal_message;
}
/* last bit of request received */
if (!(flags & MSG_PEEK)) {
_debug("eat packet");
if (skb_dequeue(&rx->sk.sk_receive_queue) !=
skb)
BUG();
rxrpc_free_skb(skb);
}
msg->msg_flags &= ~MSG_MORE;
break;
}
/* move on to the next data message */
_debug("next");
if (!continue_call)
continue_call = sp->call;
else
rxrpc_put_call(call);
call = NULL;
if (flags & MSG_PEEK) {
_debug("peek next");
skb = skb->next;
if (skb == (struct sk_buff *) &rx->sk.sk_receive_queue)
break;
goto peek_next_packet;
}
_debug("eat packet");
if (skb_dequeue(&rx->sk.sk_receive_queue) != skb)
BUG();
rxrpc_free_skb(skb);
}
/* end of non-terminal data packet reception for the moment */
_debug("end rcv data");
out:
release_sock(&rx->sk);
if (call)
rxrpc_put_call(call);
if (continue_call)
rxrpc_put_call(continue_call);
_leave(" = %d [data]", copied);
return copied;
/* handle non-DATA messages such as aborts, incoming connections and
* final ACKs */
receive_non_data_message:
_debug("non-data");
if (skb->mark == RXRPC_SKB_MARK_NEW_CALL) {
_debug("RECV NEW CALL");
ret = put_cmsg(msg, SOL_RXRPC, RXRPC_NEW_CALL, 0, &abort_code);
if (ret < 0)
goto copy_error;
if (!(flags & MSG_PEEK)) {
if (skb_dequeue(&rx->sk.sk_receive_queue) != skb)
BUG();
rxrpc_free_skb(skb);
}
goto out;
}
ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID,
ullen, &call->user_call_ID);
if (ret < 0)
goto copy_error;
ASSERT(test_bit(RXRPC_CALL_HAS_USERID, &call->flags));
switch (skb->mark) {
case RXRPC_SKB_MARK_DATA:
BUG();
case RXRPC_SKB_MARK_FINAL_ACK:
ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ACK, 0, &abort_code);
break;
case RXRPC_SKB_MARK_BUSY:
ret = put_cmsg(msg, SOL_RXRPC, RXRPC_BUSY, 0, &abort_code);
break;
case RXRPC_SKB_MARK_REMOTE_ABORT:
abort_code = call->remote_abort;
ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ABORT, 4, &abort_code);
break;
case RXRPC_SKB_MARK_LOCAL_ABORT:
abort_code = call->local_abort;
ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ABORT, 4, &abort_code);
break;
case RXRPC_SKB_MARK_NET_ERROR:
_debug("RECV NET ERROR %d", sp->error);
abort_code = sp->error;
ret = put_cmsg(msg, SOL_RXRPC, RXRPC_NET_ERROR, 4, &abort_code);
break;
case RXRPC_SKB_MARK_LOCAL_ERROR:
_debug("RECV LOCAL ERROR %d", sp->error);
abort_code = sp->error;
ret = put_cmsg(msg, SOL_RXRPC, RXRPC_LOCAL_ERROR, 4,
&abort_code);
break;
default:
pr_err("Unknown packet mark %u\n", skb->mark);
BUG();
break;
}
if (ret < 0)
goto copy_error;
terminal_message:
_debug("terminal");
msg->msg_flags &= ~MSG_MORE;
msg->msg_flags |= MSG_EOR;
if (!(flags & MSG_PEEK)) {
_net("free terminal skb %p", skb);
if (skb_dequeue(&rx->sk.sk_receive_queue) != skb)
BUG();
rxrpc_free_skb(skb);
rxrpc_remove_user_ID(rx, call);
}
release_sock(&rx->sk);
rxrpc_put_call(call);
if (continue_call)
rxrpc_put_call(continue_call);
_leave(" = %d", ret);
return ret;
copy_error:
_debug("copy error");
release_sock(&rx->sk);
rxrpc_put_call(call);
if (continue_call)
rxrpc_put_call(continue_call);
_leave(" = %d", ret);
return ret;
wait_interrupted:
ret = sock_intr_errno(timeo);
wait_error:
finish_wait(sk_sleep(&rx->sk), &wait);
if (continue_call)
rxrpc_put_call(continue_call);
if (copied)
copied = ret;
_leave(" = %d [waitfail %d]", copied, ret);
return copied;
}
/**
* rxrpc_kernel_data_delivered - Record delivery of data message
* @skb: Message holding data
*
* Record the delivery of a data message. This permits RxRPC to keep its
* tracking correct. The socket buffer will be deleted.
*/
void rxrpc_kernel_data_delivered(struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
struct rxrpc_call *call = sp->call;
ASSERTCMP(sp->hdr.seq, >=, call->rx_data_recv);
ASSERTCMP(sp->hdr.seq, <=, call->rx_data_recv + 1);
call->rx_data_recv = sp->hdr.seq;
ASSERTCMP(sp->hdr.seq, >, call->rx_data_eaten);
rxrpc_free_skb(skb);
}
EXPORT_SYMBOL(rxrpc_kernel_data_delivered);
/**
* rxrpc_kernel_is_data_last - Determine if data message is last one
* @skb: Message holding data
*
* Determine if data message is last one for the parent call.
*/
bool rxrpc_kernel_is_data_last(struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
ASSERTCMP(skb->mark, ==, RXRPC_SKB_MARK_DATA);
return sp->hdr.flags & RXRPC_LAST_PACKET;
}
EXPORT_SYMBOL(rxrpc_kernel_is_data_last);
/**
* rxrpc_kernel_get_abort_code - Get the abort code from an RxRPC abort message
* @skb: Message indicating an abort
*
* Get the abort code from an RxRPC abort message.
*/
u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
switch (skb->mark) {
case RXRPC_SKB_MARK_REMOTE_ABORT:
return sp->call->remote_abort;
case RXRPC_SKB_MARK_LOCAL_ABORT:
return sp->call->local_abort;
default:
BUG();
}
}
EXPORT_SYMBOL(rxrpc_kernel_get_abort_code);
/**
* rxrpc_kernel_get_error - Get the error number from an RxRPC error message
* @skb: Message indicating an error
*
* Get the error number from an RxRPC error message.
*/
int rxrpc_kernel_get_error_number(struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
return sp->error;
}
EXPORT_SYMBOL(rxrpc_kernel_get_error_number);
Reference in New Issue View Git Blame Copy Permalink