/*
* Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
*/
/*
* This file contains code imported from the OFED rds source file connection.c
* Oracle elects to have and use the contents of connection.c under and governed
* by the OpenIB.org BSD license (see below for full license text). However,
* the following notice accompanied the original version of this file:
*/
/*
* 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 <sys/types.h>
#include <sys/kmem.h>
#include <sys/rds.h>
#include <sys/ib/clients/rdsv3/rdsv3.h>
#include <sys/ib/clients/rdsv3/loop.h>
#include <sys/ib/clients/rdsv3/rdsv3_debug.h>
/* converting this to RCU is a chore for another day.. */
static krwlock_t rdsv3_conn_lock;
struct avl_tree rdsv3_conn_hash;
static struct kmem_cache *rdsv3_conn_slab = NULL;
#define rdsv3_conn_info_set(var, test, suffix) do { \
if (test) \
var |= RDS_INFO_CONNECTION_FLAG_##suffix; \
} while (0)
static struct rdsv3_connection *
rdsv3_conn_lookup(uint32_be_t laddr, uint32_be_t faddr, avl_index_t *pos)
{
struct rdsv3_connection *conn;
struct rdsv3_conn_info_s conn_info;
avl_index_t place = 0;
conn_info.c_laddr = laddr;
conn_info.c_faddr = faddr;
conn = avl_find(&rdsv3_conn_hash, &conn_info, &place);
RDSV3_DPRINTF5("rdsv3_conn_lookup",
"returning conn %p for %u.%u.%u.%u -> %u.%u.%u.%u",
conn, NIPQUAD(laddr), NIPQUAD(faddr));
if (pos != NULL)
*pos = place;
return (conn);
}
/*
* This is called by transports as they're bringing down a connection.
* It clears partial message state so that the transport can start sending
* and receiving over this connection again in the future. It is up to
* the transport to have serialized this call with its send and recv.
*/
void
rdsv3_conn_reset(struct rdsv3_connection *conn)
{
RDSV3_DPRINTF2("rdsv3_conn_reset",
"connection %u.%u.%u.%u to %u.%u.%u.%u reset",
NIPQUAD(conn->c_laddr), NIPQUAD(conn->c_faddr));
rdsv3_stats_inc(s_conn_reset);
rdsv3_send_reset(conn);
conn->c_flags = 0;
/*
* Do not clear next_rx_seq here, else we cannot distinguish
* retransmitted packets from new packets, and will hand all
* of them to the application. That is not consistent with the
* reliability guarantees of RDS.
*/
}
/*
* There is only every one 'conn' for a given pair of addresses in the
* system at a time. They contain messages to be retransmitted and so
* span the lifetime of the actual underlying transport connections.
*
* For now they are not garbage collected once they're created. They
* are torn down as the module is removed, if ever.
*/
static struct rdsv3_connection *
__rdsv3_conn_create(uint32_be_t laddr, uint32_be_t faddr,
struct rdsv3_transport *trans, int gfp, int is_outgoing)
{
struct rdsv3_connection *conn, *parent = NULL;
avl_index_t pos;
int ret;
rw_enter(&rdsv3_conn_lock, RW_READER);
conn = rdsv3_conn_lookup(laddr, faddr, &pos);
if (conn &&
conn->c_loopback &&
conn->c_trans != &rdsv3_loop_transport &&
!is_outgoing) {
/*
* This is a looped back IB connection, and we're
* called by the code handling the incoming connect.
* We need a second connection object into which we
* can stick the other QP.
*/
parent = conn;
conn = parent->c_passive;
}
rw_exit(&rdsv3_conn_lock);
if (conn)
goto out;
RDSV3_DPRINTF2("__rdsv3_conn_create", "Enter(%x -> %x)",
ntohl(laddr), ntohl(faddr));
conn = kmem_cache_alloc(rdsv3_conn_slab, gfp);
if (!conn) {
conn = ERR_PTR(-ENOMEM);
goto out;
}
/* see rdsv3_conn_constructor */
conn->c_laddr = laddr;
conn->c_faddr = faddr;
/*
* We don't allow sockets to send messages without binding.
* So, the IP address will already be there in the bind array.
* Mostly, this is a readonly operation.
* For now, passing GLOBAL_ZONEID.
*/
conn->c_bucketp = rdsv3_find_ip_bucket(ntohl(laddr), GLOBAL_ZONEID);
ret = rdsv3_cong_get_maps(conn);
if (ret) {
kmem_cache_free(rdsv3_conn_slab, conn);
conn = ERR_PTR(ret);
goto out;
}
/*
* This is where a connection becomes loopback. If *any* RDS sockets
* can bind to the destination address then we'd rather the messages
* flow through loopback rather than either transport.
*/
if (rdsv3_trans_get_preferred(faddr)) {
conn->c_loopback = 1;
if (is_outgoing && trans->t_prefer_loopback) {
/*
* "outgoing" connection - and the transport
* says it wants the connection handled by the
* loopback transport. This is what TCP does.
*/
trans = &rdsv3_loop_transport;
}
}
conn->c_trans = trans;
ret = trans->conn_alloc(conn, gfp);
if (ret) {
kmem_cache_free(rdsv3_conn_slab, conn);
conn = ERR_PTR(ret);
goto out;
}
conn->c_state = RDSV3_CONN_DOWN;
conn->c_reconnect_jiffies = 0;
RDSV3_INIT_DELAYED_WORK(&conn->c_send_w, rdsv3_send_worker);
RDSV3_INIT_DELAYED_WORK(&conn->c_recv_w, rdsv3_recv_worker);
RDSV3_INIT_DELAYED_WORK(&conn->c_conn_w, rdsv3_connect_worker);
RDSV3_INIT_DELAYED_WORK(&conn->c_reap_w, rdsv3_reaper_worker);
RDSV3_INIT_WORK(&conn->c_down_w, rdsv3_shutdown_worker);
mutex_init(&conn->c_cm_lock, NULL, MUTEX_DRIVER, NULL);
conn->c_flags = 0;
RDSV3_DPRINTF2("__rdsv3_conn_create",
"allocated conn %p for %u.%u.%u.%u -> %u.%u.%u.%u over %s %s",
conn, NIPQUAD(laddr), NIPQUAD(faddr),
trans->t_name ? trans->t_name : "[unknown]",
is_outgoing ? "(outgoing)" : "");
/*
* Since we ran without holding the conn lock, someone could
* have created the same conn (either normal or passive) in the
* interim. We check while holding the lock. If we won, we complete
* init and return our conn. If we lost, we rollback and return the
* other one.
*/
rw_enter(&rdsv3_conn_lock, RW_WRITER);
if (parent) {
/* Creating passive conn */
if (parent->c_passive) {
trans->conn_free(conn->c_transport_data);
kmem_cache_free(rdsv3_conn_slab, conn);
conn = parent->c_passive;
} else {
parent->c_passive = conn;
rdsv3_cong_add_conn(conn);
}
} else {
/* Creating normal conn */
struct rdsv3_connection *found;
found = rdsv3_conn_lookup(laddr, faddr, &pos);
if (found) {
trans->conn_free(conn->c_transport_data);
kmem_cache_free(rdsv3_conn_slab, conn);
conn = found;
} else {
avl_insert(&rdsv3_conn_hash, conn, pos);
rdsv3_cong_add_conn(conn);
rdsv3_queue_delayed_work(rdsv3_wq, &conn->c_reap_w,
RDSV3_REAPER_WAIT_JIFFIES);
}
}
rw_exit(&rdsv3_conn_lock);
RDSV3_DPRINTF2("__rdsv3_conn_create", "Return(conn: %p)", conn);
out:
return (conn);
}
struct rdsv3_connection *
rdsv3_conn_create(uint32_be_t laddr, uint32_be_t faddr,
struct rdsv3_transport *trans, int gfp)
{
return (__rdsv3_conn_create(laddr, faddr, trans, gfp, 0));
}
struct rdsv3_connection *
rdsv3_conn_create_outgoing(uint32_be_t laddr, uint32_be_t faddr,
struct rdsv3_transport *trans, int gfp)
{
return (__rdsv3_conn_create(laddr, faddr, trans, gfp, 1));
}
extern struct avl_tree rdsv3_conn_hash;
void
rdsv3_conn_shutdown(struct rdsv3_connection *conn)
{
RDSV3_DPRINTF2("rdsv3_conn_shutdown", "Enter(conn: %p)", conn);
/* shut it down unless it's down already */
if (!rdsv3_conn_transition(conn, RDSV3_CONN_DOWN, RDSV3_CONN_DOWN)) {
/*
* Quiesce the connection mgmt handlers before we start tearing
* things down. We don't hold the mutex for the entire
* duration of the shutdown operation, else we may be
* deadlocking with the CM handler. Instead, the CM event
* handler is supposed to check for state DISCONNECTING
*/
mutex_enter(&conn->c_cm_lock);
if (!rdsv3_conn_transition(conn, RDSV3_CONN_UP,
RDSV3_CONN_DISCONNECTING) &&
!rdsv3_conn_transition(conn, RDSV3_CONN_ERROR,
RDSV3_CONN_DISCONNECTING)) {
RDSV3_DPRINTF2("rdsv3_conn_shutdown",
"shutdown called in state %d",
atomic_get(&conn->c_state));
rdsv3_conn_drop(conn);
mutex_exit(&conn->c_cm_lock);
return;
}
mutex_exit(&conn->c_cm_lock);
/* verify everybody's out of rds_send_xmit() */
mutex_enter(&conn->c_send_lock);
while (atomic_get(&conn->c_senders)) {
mutex_exit(&conn->c_send_lock);
delay(1);
mutex_enter(&conn->c_send_lock);
}
conn->c_trans->conn_shutdown(conn);
rdsv3_conn_reset(conn);
mutex_exit(&conn->c_send_lock);
if (!rdsv3_conn_transition(conn, RDSV3_CONN_DISCONNECTING,
RDSV3_CONN_DOWN)) {
/*
* This can happen - eg when we're in the middle of
* tearing down the connection, and someone unloads
* the rds module.
* Quite reproduceable with loopback connections.
* Mostly harmless.
*/
#ifndef __lock_lint
RDSV3_DPRINTF2("rdsv3_conn_shutdown",
"failed to transition to state DOWN, "
"current statis is: %d",
atomic_get(&conn->c_state));
rdsv3_conn_drop(conn);
#endif
return;
}
}
/*
* Then reconnect if it's still live.
* The passive side of an IB loopback connection is never added
* to the conn hash, so we never trigger a reconnect on this
* conn - the reconnect is always triggered by the active peer.
*/
rdsv3_cancel_delayed_work(&conn->c_conn_w);
{
struct rdsv3_conn_info_s conn_info;
conn_info.c_laddr = conn->c_laddr;
conn_info.c_faddr = conn->c_faddr;
if (avl_find(&rdsv3_conn_hash, &conn_info, NULL) == conn)
rdsv3_queue_reconnect(conn);
}
RDSV3_DPRINTF2("rdsv3_conn_shutdown", "Exit");
}
/*
* Stop and free a connection.
*/
void
rdsv3_conn_destroy(struct rdsv3_connection *conn)
{
struct rdsv3_message *rm, *rtmp;
list_t to_be_dropped;
RDSV3_DPRINTF4("rdsv3_conn_destroy",
"freeing conn %p for %u.%u.%u.%u -> %u.%u.%u.%u",
conn, NIPQUAD(conn->c_laddr), NIPQUAD(conn->c_faddr));
avl_remove(&rdsv3_conn_hash, conn);
rdsv3_cancel_delayed_work(&conn->c_reap_w);
rdsv3_cancel_delayed_work(&conn->c_send_w);
rdsv3_cancel_delayed_work(&conn->c_recv_w);
rdsv3_conn_shutdown(conn);
/* tear down queued messages */
list_create(&to_be_dropped, sizeof (struct rdsv3_message),
offsetof(struct rdsv3_message, m_conn_item));
RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, rtmp, &conn->c_retrans, m_conn_item) {
list_remove_node(&rm->m_conn_item);
list_insert_tail(&to_be_dropped, rm);
}
RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, rtmp, &conn->c_send_queue,
m_conn_item) {
list_remove_node(&rm->m_conn_item);
list_insert_tail(&to_be_dropped, rm);
}
RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, rtmp, &to_be_dropped, m_conn_item) {
clear_bit(RDSV3_MSG_ON_CONN, &rm->m_flags);
list_remove_node(&rm->m_conn_item);
rdsv3_message_put(rm);
}
if (conn->c_xmit_rm)
rdsv3_message_put(conn->c_xmit_rm);
conn->c_trans->conn_free(conn->c_transport_data);
/*
* The congestion maps aren't freed up here. They're
* freed by rdsv3_cong_exit() after all the connections
* have been freed.
*/
rdsv3_cong_remove_conn(conn);
ASSERT(list_is_empty(&conn->c_retrans));
kmem_cache_free(rdsv3_conn_slab, conn);
}
/* ARGSUSED */
static void
rdsv3_conn_message_info(struct rsock *sock, unsigned int len,
struct rdsv3_info_iterator *iter,
struct rdsv3_info_lengths *lens,
int want_send)
{
struct list *list;
struct rdsv3_connection *conn;
struct rdsv3_message *rm;
unsigned int total = 0;
RDSV3_DPRINTF4("rdsv3_conn_message_info", "Enter");
len /= sizeof (struct rds_info_message);
rw_enter(&rdsv3_conn_lock, RW_READER);
if (avl_is_empty(&rdsv3_conn_hash)) {
/* no connections */
rw_exit(&rdsv3_conn_lock);
return;
}
conn = (struct rdsv3_connection *)avl_first(&rdsv3_conn_hash);
do {
if (want_send)
list = &conn->c_send_queue;
else
list = &conn->c_retrans;
mutex_enter(&conn->c_lock);
/* XXX too lazy to maintain counts.. */
RDSV3_FOR_EACH_LIST_NODE(rm, list, m_conn_item) {
total++;
if (total <= len)
rdsv3_inc_info_copy(&rm->m_inc, iter,
conn->c_laddr, conn->c_faddr, 0);
}
mutex_exit(&conn->c_lock);
conn = AVL_NEXT(&rdsv3_conn_hash, conn);
} while (conn != NULL);
rw_exit(&rdsv3_conn_lock);
lens->nr = total;
lens->each = sizeof (struct rds_info_message);
RDSV3_DPRINTF4("rdsv3_conn_message_info", "Return");
}
static void
rdsv3_conn_message_info_send(struct rsock *sock, unsigned int len,
struct rdsv3_info_iterator *iter,
struct rdsv3_info_lengths *lens)
{
rdsv3_conn_message_info(sock, len, iter, lens, 1);
}
static void
rdsv3_conn_message_info_retrans(struct rsock *sock,
unsigned int len,
struct rdsv3_info_iterator *iter,
struct rdsv3_info_lengths *lens)
{
rdsv3_conn_message_info(sock, len, iter, lens, 0);
}
/* ARGSUSED */
void
rdsv3_for_each_conn_info(struct rsock *sock, unsigned int len,
struct rdsv3_info_iterator *iter,
struct rdsv3_info_lengths *lens,
int (*visitor)(struct rdsv3_connection *, void *),
size_t item_len)
{
uint8_t *buffer;
struct rdsv3_connection *conn;
rw_enter(&rdsv3_conn_lock, RW_READER);
lens->nr = 0;
lens->each = item_len;
if (avl_is_empty(&rdsv3_conn_hash)) {
/* no connections */
rw_exit(&rdsv3_conn_lock);
return;
}
/* allocate a little extra as this can get cast to a uint64_t */
buffer = kmem_zalloc(item_len + 8, KM_SLEEP);
conn = (struct rdsv3_connection *)avl_first(&rdsv3_conn_hash);
do {
/* XXX no c_lock usage.. */
if (visitor(conn, buffer)) {
/*
* We copy as much as we can fit in the buffer,
* but we count all items so that the caller
* can resize the buffer.
*/
if (len >= item_len) {
RDSV3_DPRINTF4("rdsv3_for_each_conn_info",
"buffer: %p iter: %p bytes: %d", buffer,
iter->addr + iter->offset, item_len);
rdsv3_info_copy(iter, buffer, item_len);
len -= item_len;
}
lens->nr++;
}
conn = AVL_NEXT(&rdsv3_conn_hash, conn);
} while (conn != NULL);
rw_exit(&rdsv3_conn_lock);
kmem_free(buffer, item_len + 8);
}
static int
rdsv3_conn_info_visitor(struct rdsv3_connection *conn, void *buffer)
{
struct rds_info_connection *cinfo = buffer;
cinfo->next_tx_seq = conn->c_next_tx_seq;
cinfo->next_rx_seq = conn->c_next_rx_seq;
cinfo->laddr = conn->c_laddr;
cinfo->faddr = conn->c_faddr;
(void) strncpy((char *)cinfo->transport, conn->c_trans->t_name,
sizeof (cinfo->transport));
cinfo->flags = 0;
rdsv3_conn_info_set(cinfo->flags,
MUTEX_HELD(&conn->c_send_lock), SENDING);
/* XXX Future: return the state rather than these funky bits */
rdsv3_conn_info_set(cinfo->flags,
atomic_get(&conn->c_state) == RDSV3_CONN_CONNECTING,
CONNECTING);
rdsv3_conn_info_set(cinfo->flags,
atomic_get(&conn->c_state) == RDSV3_CONN_UP,
CONNECTED);
return (1);
}
static void
rdsv3_conn_info(struct rsock *sock, unsigned int len,
struct rdsv3_info_iterator *iter, struct rdsv3_info_lengths *lens)
{
rdsv3_for_each_conn_info(sock, len, iter, lens,
rdsv3_conn_info_visitor, sizeof (struct rds_info_connection));
}
int
rdsv3_conn_init()
{
RDSV3_DPRINTF4("rdsv3_conn_init", "Enter");
rdsv3_conn_slab = kmem_cache_create("rdsv3_connection",
sizeof (struct rdsv3_connection), 0, rdsv3_conn_constructor,
rdsv3_conn_destructor, NULL, NULL, NULL, 0);
if (!rdsv3_conn_slab) {
RDSV3_DPRINTF2("rdsv3_conn_init",
"kmem_cache_create(rdsv3_conn_slab) failed");
return (-ENOMEM);
}
avl_create(&rdsv3_conn_hash, rdsv3_conn_compare,
sizeof (struct rdsv3_connection), offsetof(struct rdsv3_connection,
c_hash_node));
rw_init(&rdsv3_conn_lock, NULL, RW_DRIVER, NULL);
rdsv3_loop_init();
rdsv3_info_register_func(RDS_INFO_CONNECTIONS, rdsv3_conn_info);
rdsv3_info_register_func(RDS_INFO_SEND_MESSAGES,
rdsv3_conn_message_info_send);
rdsv3_info_register_func(RDS_INFO_RETRANS_MESSAGES,
rdsv3_conn_message_info_retrans);
RDSV3_DPRINTF4("rdsv3_conn_init", "Return");
return (0);
}
void
rdsv3_conn_exit()
{
RDSV3_DPRINTF4("rdsv3_conn_exit", "Enter");
rdsv3_loop_exit();
rw_destroy(&rdsv3_conn_lock);
avl_destroy(&rdsv3_conn_hash);
ASSERT(rdsv3_conn_slab);
kmem_cache_destroy(rdsv3_conn_slab);
RDSV3_DPRINTF4("rdsv3_conn_exit", "Return");
}
/*
* Force a disconnect
*/
void
rdsv3_conn_drop(struct rdsv3_connection *conn)
{
conn->c_state = RDSV3_CONN_ERROR;
rdsv3_queue_work(rdsv3_wq, &conn->c_down_w);
}