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|
/*
* Copyright (c) 2006 Oracle. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <linux/in.h>
#include <linux/export.h>
#include <linux/time.h>
#include <linux/rds.h>
#include "rds.h"
void rds_inc_init(struct rds_incoming *inc, struct rds_connection *conn,
__be32 saddr)
{
atomic_set(&inc->i_refcount, 1);
INIT_LIST_HEAD(&inc->i_item);
inc->i_conn = conn;
inc->i_saddr = saddr;
inc->i_rdma_cookie = 0;
inc->i_rx_tstamp.tv_sec = 0;
inc->i_rx_tstamp.tv_usec = 0;
}
EXPORT_SYMBOL_GPL(rds_inc_init);
void rds_inc_path_init(struct rds_incoming *inc, struct rds_conn_path *cp,
__be32 saddr)
{
atomic_set(&inc->i_refcount, 1);
INIT_LIST_HEAD(&inc->i_item);
inc->i_conn = cp->cp_conn;
inc->i_conn_path = cp;
inc->i_saddr = saddr;
inc->i_rdma_cookie = 0;
inc->i_rx_tstamp.tv_sec = 0;
inc->i_rx_tstamp.tv_usec = 0;
}
EXPORT_SYMBOL_GPL(rds_inc_path_init);
static void rds_inc_addref(struct rds_incoming *inc)
{
rdsdebug("addref inc %p ref %d\n", inc, atomic_read(&inc->i_refcount));
atomic_inc(&inc->i_refcount);
}
void rds_inc_put(struct rds_incoming *inc)
{
rdsdebug("put inc %p ref %d\n", inc, atomic_read(&inc->i_refcount));
if (atomic_dec_and_test(&inc->i_refcount)) {
BUG_ON(!list_empty(&inc->i_item));
inc->i_conn->c_trans->inc_free(inc);
}
}
EXPORT_SYMBOL_GPL(rds_inc_put);
static void rds_recv_rcvbuf_delta(struct rds_sock *rs, struct sock *sk,
struct rds_cong_map *map,
int delta, __be16 port)
{
int now_congested;
if (delta == 0)
return;
rs->rs_rcv_bytes += delta;
now_congested = rs->rs_rcv_bytes > rds_sk_rcvbuf(rs);
rdsdebug("rs %p (%pI4:%u) recv bytes %d buf %d "
"now_cong %d delta %d\n",
rs, &rs->rs_bound_addr,
ntohs(rs->rs_bound_port), rs->rs_rcv_bytes,
rds_sk_rcvbuf(rs), now_congested, delta);
/* wasn't -> am congested */
if (!rs->rs_congested && now_congested) {
rs->rs_congested = 1;
rds_cong_set_bit(map, port);
rds_cong_queue_updates(map);
}
/* was -> aren't congested */
/* Require more free space before reporting uncongested to prevent
bouncing cong/uncong state too often */
else if (rs->rs_congested && (rs->rs_rcv_bytes < (rds_sk_rcvbuf(rs)/2))) {
rs->rs_congested = 0;
rds_cong_clear_bit(map, port);
rds_cong_queue_updates(map);
}
/* do nothing if no change in cong state */
}
/*
* Process all extension headers that come with this message.
*/
static void rds_recv_incoming_exthdrs(struct rds_incoming *inc, struct rds_sock *rs)
{
struct rds_header *hdr = &inc->i_hdr;
unsigned int pos = 0, type, len;
union {
struct rds_ext_header_version version;
struct rds_ext_header_rdma rdma;
struct rds_ext_header_rdma_dest rdma_dest;
} buffer;
while (1) {
len = sizeof(buffer);
type = rds_message_next_extension(hdr, &pos, &buffer, &len);
if (type == RDS_EXTHDR_NONE)
break;
/* Process extension header here */
switch (type) {
case RDS_EXTHDR_RDMA:
rds_rdma_unuse(rs, be32_to_cpu(buffer.rdma.h_rdma_rkey), 0);
break;
case RDS_EXTHDR_RDMA_DEST:
/* We ignore the size for now. We could stash it
* somewhere and use it for error checking. */
inc->i_rdma_cookie = rds_rdma_make_cookie(
be32_to_cpu(buffer.rdma_dest.h_rdma_rkey),
be32_to_cpu(buffer.rdma_dest.h_rdma_offset));
break;
}
}
}
static void rds_recv_hs_exthdrs(struct rds_header *hdr,
struct rds_connection *conn)
{
unsigned int pos = 0, type, len;
union {
struct rds_ext_header_version version;
u16 rds_npaths;
} buffer;
while (1) {
len = sizeof(buffer);
type = rds_message_next_extension(hdr, &pos, &buffer, &len);
if (type == RDS_EXTHDR_NONE)
break;
/* Process extension header here */
switch (type) {
case RDS_EXTHDR_NPATHS:
conn->c_npaths = min_t(int, RDS_MPATH_WORKERS,
buffer.rds_npaths);
break;
default:
pr_warn_ratelimited("ignoring unknown exthdr type "
"0x%x\n", type);
}
}
/* if RDS_EXTHDR_NPATHS was not found, default to a single-path */
conn->c_npaths = max_t(int, conn->c_npaths, 1);
}
/* rds_start_mprds() will synchronously start multiple paths when appropriate.
* The scheme is based on the following rules:
*
* 1. rds_sendmsg on first connect attempt sends the probe ping, with the
* sender's npaths (s_npaths)
* 2. rcvr of probe-ping knows the mprds_paths = min(s_npaths, r_npaths). It
* sends back a probe-pong with r_npaths. After that, if rcvr is the
* smaller ip addr, it starts rds_conn_path_connect_if_down on all
* mprds_paths.
* 3. sender gets woken up, and can move to rds_conn_path_connect_if_down.
* If it is the smaller ipaddr, rds_conn_path_connect_if_down can be
* called after reception of the probe-pong on all mprds_paths.
* Otherwise (sender of probe-ping is not the smaller ip addr): just call
* rds_conn_path_connect_if_down on the hashed path. (see rule 4)
* 4. when cp_index > 0, rds_connect_worker must only trigger
* a connection if laddr < faddr.
* 5. sender may end up queuing the packet on the cp. will get sent out later.
* when connection is completed.
*/
static void rds_start_mprds(struct rds_connection *conn)
{
int i;
struct rds_conn_path *cp;
if (conn->c_npaths > 1 && conn->c_laddr < conn->c_faddr) {
for (i = 1; i < conn->c_npaths; i++) {
cp = &conn->c_path[i];
rds_conn_path_connect_if_down(cp);
}
}
}
/*
* The transport must make sure that this is serialized against other
* rx and conn reset on this specific conn.
*
* We currently assert that only one fragmented message will be sent
* down a connection at a time. This lets us reassemble in the conn
* instead of per-flow which means that we don't have to go digging through
* flows to tear down partial reassembly progress on conn failure and
* we save flow lookup and locking for each frag arrival. It does mean
* that small messages will wait behind large ones. Fragmenting at all
* is only to reduce the memory consumption of pre-posted buffers.
*
* The caller passes in saddr and daddr instead of us getting it from the
* conn. This lets loopback, who only has one conn for both directions,
* tell us which roles the addrs in the conn are playing for this message.
*/
void rds_recv_incoming(struct
|