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author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-27 12:03:20 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-27 12:03:20 -0700 |
commit | 468fc7ed5537615efe671d94248446ac24679773 (patch) | |
tree | 27bc9de792e863d6ec1630927b77ac9e7dabb38a /net/rxrpc/recvmsg.c | |
parent | 08fd8c17686c6b09fa410a26d516548dd80ff147 (diff) | |
parent | 36232012344b8db67052432742deaf17f82e70e6 (diff) | |
download | lwn-468fc7ed5537615efe671d94248446ac24679773.tar.gz lwn-468fc7ed5537615efe671d94248446ac24679773.zip |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
1) Unified UDP encapsulation offload methods for drivers, from
Alexander Duyck.
2) Make DSA binding more sane, from Andrew Lunn.
3) Support QCA9888 chips in ath10k, from Anilkumar Kolli.
4) Several workqueue usage cleanups, from Bhaktipriya Shridhar.
5) Add XDP (eXpress Data Path), essentially running BPF programs on RX
packets as soon as the device sees them, with the option to mirror
the packet on TX via the same interface. From Brenden Blanco and
others.
6) Allow qdisc/class stats dumps to run lockless, from Eric Dumazet.
7) Add VLAN support to b53 and bcm_sf2, from Florian Fainelli.
8) Simplify netlink conntrack entry layout, from Florian Westphal.
9) Add ipv4 forwarding support to mlxsw spectrum driver, from Ido
Schimmel, Yotam Gigi, and Jiri Pirko.
10) Add SKB array infrastructure and convert tun and macvtap over to it.
From Michael S Tsirkin and Jason Wang.
11) Support qdisc packet injection in pktgen, from John Fastabend.
12) Add neighbour monitoring framework to TIPC, from Jon Paul Maloy.
13) Add NV congestion control support to TCP, from Lawrence Brakmo.
14) Add GSO support to SCTP, from Marcelo Ricardo Leitner.
15) Allow GRO and RPS to function on macsec devices, from Paolo Abeni.
16) Support MPLS over IPV4, from Simon Horman.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1622 commits)
xgene: Fix build warning with ACPI disabled.
be2net: perform temperature query in adapter regardless of its interface state
l2tp: Correctly return -EBADF from pppol2tp_getname.
net/mlx5_core/health: Remove deprecated create_singlethread_workqueue
net: ipmr/ip6mr: update lastuse on entry change
macsec: ensure rx_sa is set when validation is disabled
tipc: dump monitor attributes
tipc: add a function to get the bearer name
tipc: get monitor threshold for the cluster
tipc: make cluster size threshold for monitoring configurable
tipc: introduce constants for tipc address validation
net: neigh: disallow transition to NUD_STALE if lladdr is unchanged in neigh_update()
MAINTAINERS: xgene: Add driver and documentation path
Documentation: dtb: xgene: Add MDIO node
dtb: xgene: Add MDIO node
drivers: net: xgene: ethtool: Use phy_ethtool_gset and sset
drivers: net: xgene: Use exported functions
drivers: net: xgene: Enable MDIO driver
drivers: net: xgene: Add backward compatibility
drivers: net: phy: xgene: Add MDIO driver
...
Diffstat (limited to 'net/rxrpc/recvmsg.c')
-rw-r--r-- | net/rxrpc/recvmsg.c | 436 |
1 files changed, 436 insertions, 0 deletions
diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c new file mode 100644 index 000000000000..a3fa2ed85d63 --- /dev/null +++ b/net/rxrpc/recvmsg.c @@ -0,0 +1,436 @@ +/* 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->params.peer->srx); + memcpy(msg->msg_name, + &call->conn->params.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 (rxrpc_conn_is_client(call->conn)) { + /* 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); |