linux/net/rds/connection.c
Rao Shoaib 9ef845f894 rds: If one path needs re-connection, check all and re-connect
In testing with mprds enabled, Oracle Cluster nodes after reboot were
not able to communicate with others nodes and so failed to rejoin
the cluster. Peers with lower IP address initiated connection but the
node could not respond as it choose a different path and could not
initiate a connection as it had a higher IP address.

With this patch, when a node sends out a packet and the selected path
is down, all other paths are also checked and any down paths are
re-connected.

Reviewed-by: Ka-cheong Poon <ka-cheong.poon@oracle.com>
Reviewed-by: David Edmondson <david.edmondson@oracle.com>
Signed-off-by: Somasundaram Krishnasamy <somasundaram.krishnasamy@oracle.com>
Signed-off-by: Rao Shoaib <rao.shoaib@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-01 17:35:17 -07:00

937 lines
26 KiB
C

/*
* Copyright (c) 2006, 2018 Oracle and/or its affiliates. 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/list.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <net/ipv6.h>
#include <net/inet6_hashtables.h>
#include <net/addrconf.h>
#include "rds.h"
#include "loop.h"
#define RDS_CONNECTION_HASH_BITS 12
#define RDS_CONNECTION_HASH_ENTRIES (1 << RDS_CONNECTION_HASH_BITS)
#define RDS_CONNECTION_HASH_MASK (RDS_CONNECTION_HASH_ENTRIES - 1)
/* converting this to RCU is a chore for another day.. */
static DEFINE_SPINLOCK(rds_conn_lock);
static unsigned long rds_conn_count;
static struct hlist_head rds_conn_hash[RDS_CONNECTION_HASH_ENTRIES];
static struct kmem_cache *rds_conn_slab;
static struct hlist_head *rds_conn_bucket(const struct in6_addr *laddr,
const struct in6_addr *faddr)
{
static u32 rds6_hash_secret __read_mostly;
static u32 rds_hash_secret __read_mostly;
u32 lhash, fhash, hash;
net_get_random_once(&rds_hash_secret, sizeof(rds_hash_secret));
net_get_random_once(&rds6_hash_secret, sizeof(rds6_hash_secret));
lhash = (__force u32)laddr->s6_addr32[3];
#if IS_ENABLED(CONFIG_IPV6)
fhash = __ipv6_addr_jhash(faddr, rds6_hash_secret);
#else
fhash = (__force u32)faddr->s6_addr32[3];
#endif
hash = __inet_ehashfn(lhash, 0, fhash, 0, rds_hash_secret);
return &rds_conn_hash[hash & RDS_CONNECTION_HASH_MASK];
}
#define rds_conn_info_set(var, test, suffix) do { \
if (test) \
var |= RDS_INFO_CONNECTION_FLAG_##suffix; \
} while (0)
/* rcu read lock must be held or the connection spinlock */
static struct rds_connection *rds_conn_lookup(struct net *net,
struct hlist_head *head,
const struct in6_addr *laddr,
const struct in6_addr *faddr,
struct rds_transport *trans,
u8 tos, int dev_if)
{
struct rds_connection *conn, *ret = NULL;
hlist_for_each_entry_rcu(conn, head, c_hash_node) {
if (ipv6_addr_equal(&conn->c_faddr, faddr) &&
ipv6_addr_equal(&conn->c_laddr, laddr) &&
conn->c_trans == trans &&
conn->c_tos == tos &&
net == rds_conn_net(conn) &&
conn->c_dev_if == dev_if) {
ret = conn;
break;
}
}
rdsdebug("returning conn %p for %pI6c -> %pI6c\n", ret,
laddr, faddr);
return ret;
}
/*
* 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.
*/
static void rds_conn_path_reset(struct rds_conn_path *cp)
{
struct rds_connection *conn = cp->cp_conn;
rdsdebug("connection %pI6c to %pI6c reset\n",
&conn->c_laddr, &conn->c_faddr);
rds_stats_inc(s_conn_reset);
rds_send_path_reset(cp);
cp->cp_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. */
}
static void __rds_conn_path_init(struct rds_connection *conn,
struct rds_conn_path *cp, bool is_outgoing)
{
spin_lock_init(&cp->cp_lock);
cp->cp_next_tx_seq = 1;
init_waitqueue_head(&cp->cp_waitq);
INIT_LIST_HEAD(&cp->cp_send_queue);
INIT_LIST_HEAD(&cp->cp_retrans);
cp->cp_conn = conn;
atomic_set(&cp->cp_state, RDS_CONN_DOWN);
cp->cp_send_gen = 0;
cp->cp_reconnect_jiffies = 0;
cp->cp_conn->c_proposed_version = RDS_PROTOCOL_VERSION;
INIT_DELAYED_WORK(&cp->cp_send_w, rds_send_worker);
INIT_DELAYED_WORK(&cp->cp_recv_w, rds_recv_worker);
INIT_DELAYED_WORK(&cp->cp_conn_w, rds_connect_worker);
INIT_WORK(&cp->cp_down_w, rds_shutdown_worker);
mutex_init(&cp->cp_cm_lock);
cp->cp_flags = 0;
}
/*
* 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 rds_connection *__rds_conn_create(struct net *net,
const struct in6_addr *laddr,
const struct in6_addr *faddr,
struct rds_transport *trans,
gfp_t gfp, u8 tos,
int is_outgoing,
int dev_if)
{
struct rds_connection *conn, *parent = NULL;
struct hlist_head *head = rds_conn_bucket(laddr, faddr);
struct rds_transport *loop_trans;
unsigned long flags;
int ret, i;
int npaths = (trans->t_mp_capable ? RDS_MPATH_WORKERS : 1);
rcu_read_lock();
conn = rds_conn_lookup(net, head, laddr, faddr, trans, tos, dev_if);
if (conn &&
conn->c_loopback &&
conn->c_trans != &rds_loop_transport &&
ipv6_addr_equal(laddr, faddr) &&
!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;
}
rcu_read_unlock();
if (conn)
goto out;
conn = kmem_cache_zalloc(rds_conn_slab, gfp);
if (!conn) {
conn = ERR_PTR(-ENOMEM);
goto out;
}
conn->c_path = kcalloc(npaths, sizeof(struct rds_conn_path), gfp);
if (!conn->c_path) {
kmem_cache_free(rds_conn_slab, conn);
conn = ERR_PTR(-ENOMEM);
goto out;
}
INIT_HLIST_NODE(&conn->c_hash_node);
conn->c_laddr = *laddr;
conn->c_isv6 = !ipv6_addr_v4mapped(laddr);
conn->c_faddr = *faddr;
conn->c_dev_if = dev_if;
conn->c_tos = tos;
#if IS_ENABLED(CONFIG_IPV6)
/* If the local address is link local, set c_bound_if to be the
* index used for this connection. Otherwise, set it to 0 as
* the socket is not bound to an interface. c_bound_if is used
* to look up a socket when a packet is received
*/
if (ipv6_addr_type(laddr) & IPV6_ADDR_LINKLOCAL)
conn->c_bound_if = dev_if;
else
#endif
conn->c_bound_if = 0;
rds_conn_net_set(conn, net);
ret = rds_cong_get_maps(conn);
if (ret) {
kfree(conn->c_path);
kmem_cache_free(rds_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.
*/
loop_trans = rds_trans_get_preferred(net, faddr, conn->c_dev_if);
if (loop_trans) {
rds_trans_put(loop_trans);
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 = &rds_loop_transport;
}
}
conn->c_trans = trans;
init_waitqueue_head(&conn->c_hs_waitq);
for (i = 0; i < npaths; i++) {
__rds_conn_path_init(conn, &conn->c_path[i],
is_outgoing);
conn->c_path[i].cp_index = i;
}
rcu_read_lock();
if (rds_destroy_pending(conn))
ret = -ENETDOWN;
else
ret = trans->conn_alloc(conn, GFP_ATOMIC);
if (ret) {
rcu_read_unlock();
kfree(conn->c_path);
kmem_cache_free(rds_conn_slab, conn);
conn = ERR_PTR(ret);
goto out;
}
rdsdebug("allocated conn %p for %pI6c -> %pI6c over %s %s\n",
conn, laddr, faddr,
strnlen(trans->t_name, sizeof(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.
*/
spin_lock_irqsave(&rds_conn_lock, flags);
if (parent) {
/* Creating passive conn */
if (parent->c_passive) {
trans->conn_free(conn->c_path[0].cp_transport_data);
kfree(conn->c_path);
kmem_cache_free(rds_conn_slab, conn);
conn = parent->c_passive;
} else {
parent->c_passive = conn;
rds_cong_add_conn(conn);
rds_conn_count++;
}
} else {
/* Creating normal conn */
struct rds_connection *found;
found = rds_conn_lookup(net, head, laddr, faddr, trans,
tos, dev_if);
if (found) {
struct rds_conn_path *cp;
int i;
for (i = 0; i < npaths; i++) {
cp = &conn->c_path[i];
/* The ->conn_alloc invocation may have
* allocated resource for all paths, so all
* of them may have to be freed here.
*/
if (cp->cp_transport_data)
trans->conn_free(cp->cp_transport_data);
}
kfree(conn->c_path);
kmem_cache_free(rds_conn_slab, conn);
conn = found;
} else {
conn->c_my_gen_num = rds_gen_num;
conn->c_peer_gen_num = 0;
hlist_add_head_rcu(&conn->c_hash_node, head);
rds_cong_add_conn(conn);
rds_conn_count++;
}
}
spin_unlock_irqrestore(&rds_conn_lock, flags);
rcu_read_unlock();
out:
return conn;
}
struct rds_connection *rds_conn_create(struct net *net,
const struct in6_addr *laddr,
const struct in6_addr *faddr,
struct rds_transport *trans, u8 tos,
gfp_t gfp, int dev_if)
{
return __rds_conn_create(net, laddr, faddr, trans, gfp, tos, 0, dev_if);
}
EXPORT_SYMBOL_GPL(rds_conn_create);
struct rds_connection *rds_conn_create_outgoing(struct net *net,
const struct in6_addr *laddr,
const struct in6_addr *faddr,
struct rds_transport *trans,
u8 tos, gfp_t gfp, int dev_if)
{
return __rds_conn_create(net, laddr, faddr, trans, gfp, tos, 1, dev_if);
}
EXPORT_SYMBOL_GPL(rds_conn_create_outgoing);
void rds_conn_shutdown(struct rds_conn_path *cp)
{
struct rds_connection *conn = cp->cp_conn;
/* shut it down unless it's down already */
if (!rds_conn_path_transition(cp, RDS_CONN_DOWN, RDS_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_lock(&cp->cp_cm_lock);
if (!rds_conn_path_transition(cp, RDS_CONN_UP,
RDS_CONN_DISCONNECTING) &&
!rds_conn_path_transition(cp, RDS_CONN_ERROR,
RDS_CONN_DISCONNECTING)) {
rds_conn_path_error(cp,
"shutdown called in state %d\n",
atomic_read(&cp->cp_state));
mutex_unlock(&cp->cp_cm_lock);
return;
}
mutex_unlock(&cp->cp_cm_lock);
wait_event(cp->cp_waitq,
!test_bit(RDS_IN_XMIT, &cp->cp_flags));
wait_event(cp->cp_waitq,
!test_bit(RDS_RECV_REFILL, &cp->cp_flags));
conn->c_trans->conn_path_shutdown(cp);
rds_conn_path_reset(cp);
if (!rds_conn_path_transition(cp, RDS_CONN_DISCONNECTING,
RDS_CONN_DOWN) &&
!rds_conn_path_transition(cp, RDS_CONN_ERROR,
RDS_CONN_DOWN)) {
/* This can happen - eg when we're in the middle of tearing
* down the connection, and someone unloads the rds module.
* Quite reproducible with loopback connections.
* Mostly harmless.
*
* Note that this also happens with rds-tcp because
* we could have triggered rds_conn_path_drop in irq
* mode from rds_tcp_state change on the receipt of
* a FIN, thus we need to recheck for RDS_CONN_ERROR
* here.
*/
rds_conn_path_error(cp, "%s: failed to transition "
"to state DOWN, current state "
"is %d\n", __func__,
atomic_read(&cp->cp_state));
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. */
cancel_delayed_work_sync(&cp->cp_conn_w);
rcu_read_lock();
if (!hlist_unhashed(&conn->c_hash_node)) {
rcu_read_unlock();
rds_queue_reconnect(cp);
} else {
rcu_read_unlock();
}
}
/* destroy a single rds_conn_path. rds_conn_destroy() iterates over
* all paths using rds_conn_path_destroy()
*/
static void rds_conn_path_destroy(struct rds_conn_path *cp)
{
struct rds_message *rm, *rtmp;
if (!cp->cp_transport_data)
return;
/* make sure lingering queued work won't try to ref the conn */
cancel_delayed_work_sync(&cp->cp_send_w);
cancel_delayed_work_sync(&cp->cp_recv_w);
rds_conn_path_drop(cp, true);
flush_work(&cp->cp_down_w);
/* tear down queued messages */
list_for_each_entry_safe(rm, rtmp,
&cp->cp_send_queue,
m_conn_item) {
list_del_init(&rm->m_conn_item);
BUG_ON(!list_empty(&rm->m_sock_item));
rds_message_put(rm);
}
if (cp->cp_xmit_rm)
rds_message_put(cp->cp_xmit_rm);
WARN_ON(delayed_work_pending(&cp->cp_send_w));
WARN_ON(delayed_work_pending(&cp->cp_recv_w));
WARN_ON(delayed_work_pending(&cp->cp_conn_w));
WARN_ON(work_pending(&cp->cp_down_w));
cp->cp_conn->c_trans->conn_free(cp->cp_transport_data);
}
/*
* Stop and free a connection.
*
* This can only be used in very limited circumstances. It assumes that once
* the conn has been shutdown that no one else is referencing the connection.
* We can only ensure this in the rmmod path in the current code.
*/
void rds_conn_destroy(struct rds_connection *conn)
{
unsigned long flags;
int i;
struct rds_conn_path *cp;
int npaths = (conn->c_trans->t_mp_capable ? RDS_MPATH_WORKERS : 1);
rdsdebug("freeing conn %p for %pI4 -> "
"%pI4\n", conn, &conn->c_laddr,
&conn->c_faddr);
/* Ensure conn will not be scheduled for reconnect */
spin_lock_irq(&rds_conn_lock);
hlist_del_init_rcu(&conn->c_hash_node);
spin_unlock_irq(&rds_conn_lock);
synchronize_rcu();
/* shut the connection down */
for (i = 0; i < npaths; i++) {
cp = &conn->c_path[i];
rds_conn_path_destroy(cp);
BUG_ON(!list_empty(&cp->cp_retrans));
}
/*
* The congestion maps aren't freed up here. They're
* freed by rds_cong_exit() after all the connections
* have been freed.
*/
rds_cong_remove_conn(conn);
kfree(conn->c_path);
kmem_cache_free(rds_conn_slab, conn);
spin_lock_irqsave(&rds_conn_lock, flags);
rds_conn_count--;
spin_unlock_irqrestore(&rds_conn_lock, flags);
}
EXPORT_SYMBOL_GPL(rds_conn_destroy);
static void __rds_inc_msg_cp(struct rds_incoming *inc,
struct rds_info_iterator *iter,
void *saddr, void *daddr, int flip, bool isv6)
{
#if IS_ENABLED(CONFIG_IPV6)
if (isv6)
rds6_inc_info_copy(inc, iter, saddr, daddr, flip);
else
#endif
rds_inc_info_copy(inc, iter, *(__be32 *)saddr,
*(__be32 *)daddr, flip);
}
static void rds_conn_message_info_cmn(struct socket *sock, unsigned int len,
struct rds_info_iterator *iter,
struct rds_info_lengths *lens,
int want_send, bool isv6)
{
struct hlist_head *head;
struct list_head *list;
struct rds_connection *conn;
struct rds_message *rm;
unsigned int total = 0;
unsigned long flags;
size_t i;
int j;
if (isv6)
len /= sizeof(struct rds6_info_message);
else
len /= sizeof(struct rds_info_message);
rcu_read_lock();
for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
i++, head++) {
hlist_for_each_entry_rcu(conn, head, c_hash_node) {
struct rds_conn_path *cp;
int npaths;
if (!isv6 && conn->c_isv6)
continue;
npaths = (conn->c_trans->t_mp_capable ?
RDS_MPATH_WORKERS : 1);
for (j = 0; j < npaths; j++) {
cp = &conn->c_path[j];
if (want_send)
list = &cp->cp_send_queue;
else
list = &cp->cp_retrans;
spin_lock_irqsave(&cp->cp_lock, flags);
/* XXX too lazy to maintain counts.. */
list_for_each_entry(rm, list, m_conn_item) {
total++;
if (total <= len)
__rds_inc_msg_cp(&rm->m_inc,
iter,
&conn->c_laddr,
&conn->c_faddr,
0, isv6);
}
spin_unlock_irqrestore(&cp->cp_lock, flags);
}
}
}
rcu_read_unlock();
lens->nr = total;
if (isv6)
lens->each = sizeof(struct rds6_info_message);
else
lens->each = sizeof(struct rds_info_message);
}
static void rds_conn_message_info(struct socket *sock, unsigned int len,
struct rds_info_iterator *iter,
struct rds_info_lengths *lens,
int want_send)
{
rds_conn_message_info_cmn(sock, len, iter, lens, want_send, false);
}
#if IS_ENABLED(CONFIG_IPV6)
static void rds6_conn_message_info(struct socket *sock, unsigned int len,
struct rds_info_iterator *iter,
struct rds_info_lengths *lens,
int want_send)
{
rds_conn_message_info_cmn(sock, len, iter, lens, want_send, true);
}
#endif
static void rds_conn_message_info_send(struct socket *sock, unsigned int len,
struct rds_info_iterator *iter,
struct rds_info_lengths *lens)
{
rds_conn_message_info(sock, len, iter, lens, 1);
}
#if IS_ENABLED(CONFIG_IPV6)
static void rds6_conn_message_info_send(struct socket *sock, unsigned int len,
struct rds_info_iterator *iter,
struct rds_info_lengths *lens)
{
rds6_conn_message_info(sock, len, iter, lens, 1);
}
#endif
static void rds_conn_message_info_retrans(struct socket *sock,
unsigned int len,
struct rds_info_iterator *iter,
struct rds_info_lengths *lens)
{
rds_conn_message_info(sock, len, iter, lens, 0);
}
#if IS_ENABLED(CONFIG_IPV6)
static void rds6_conn_message_info_retrans(struct socket *sock,
unsigned int len,
struct rds_info_iterator *iter,
struct rds_info_lengths *lens)
{
rds6_conn_message_info(sock, len, iter, lens, 0);
}
#endif
void rds_for_each_conn_info(struct socket *sock, unsigned int len,
struct rds_info_iterator *iter,
struct rds_info_lengths *lens,
int (*visitor)(struct rds_connection *, void *),
u64 *buffer,
size_t item_len)
{
struct hlist_head *head;
struct rds_connection *conn;
size_t i;
rcu_read_lock();
lens->nr = 0;
lens->each = item_len;
for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
i++, head++) {
hlist_for_each_entry_rcu(conn, head, c_hash_node) {
/* XXX no c_lock usage.. */
if (!visitor(conn, buffer))
continue;
/* 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) {
rds_info_copy(iter, buffer, item_len);
len -= item_len;
}
lens->nr++;
}
}
rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(rds_for_each_conn_info);
static void rds_walk_conn_path_info(struct socket *sock, unsigned int len,
struct rds_info_iterator *iter,
struct rds_info_lengths *lens,
int (*visitor)(struct rds_conn_path *, void *),
u64 *buffer,
size_t item_len)
{
struct hlist_head *head;
struct rds_connection *conn;
size_t i;
rcu_read_lock();
lens->nr = 0;
lens->each = item_len;
for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
i++, head++) {
hlist_for_each_entry_rcu(conn, head, c_hash_node) {
struct rds_conn_path *cp;
/* XXX We only copy the information from the first
* path for now. The problem is that if there are
* more than one underlying paths, we cannot report
* information of all of them using the existing
* API. For example, there is only one next_tx_seq,
* which path's next_tx_seq should we report? It is
* a bug in the design of MPRDS.
*/
cp = conn->c_path;
/* XXX no cp_lock usage.. */
if (!visitor(cp, buffer))
continue;
/* 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) {
rds_info_copy(iter, buffer, item_len);
len -= item_len;
}
lens->nr++;
}
}
rcu_read_unlock();
}
static int rds_conn_info_visitor(struct rds_conn_path *cp, void *buffer)
{
struct rds_info_connection *cinfo = buffer;
struct rds_connection *conn = cp->cp_conn;
if (conn->c_isv6)
return 0;
cinfo->next_tx_seq = cp->cp_next_tx_seq;
cinfo->next_rx_seq = cp->cp_next_rx_seq;
cinfo->laddr = conn->c_laddr.s6_addr32[3];
cinfo->faddr = conn->c_faddr.s6_addr32[3];
cinfo->tos = conn->c_tos;
strncpy(cinfo->transport, conn->c_trans->t_name,
sizeof(cinfo->transport));
cinfo->flags = 0;
rds_conn_info_set(cinfo->flags, test_bit(RDS_IN_XMIT, &cp->cp_flags),
SENDING);
/* XXX Future: return the state rather than these funky bits */
rds_conn_info_set(cinfo->flags,
atomic_read(&cp->cp_state) == RDS_CONN_CONNECTING,
CONNECTING);
rds_conn_info_set(cinfo->flags,
atomic_read(&cp->cp_state) == RDS_CONN_UP,
CONNECTED);
return 1;
}
#if IS_ENABLED(CONFIG_IPV6)
static int rds6_conn_info_visitor(struct rds_conn_path *cp, void *buffer)
{
struct rds6_info_connection *cinfo6 = buffer;
struct rds_connection *conn = cp->cp_conn;
cinfo6->next_tx_seq = cp->cp_next_tx_seq;
cinfo6->next_rx_seq = cp->cp_next_rx_seq;
cinfo6->laddr = conn->c_laddr;
cinfo6->faddr = conn->c_faddr;
strncpy(cinfo6->transport, conn->c_trans->t_name,
sizeof(cinfo6->transport));
cinfo6->flags = 0;
rds_conn_info_set(cinfo6->flags, test_bit(RDS_IN_XMIT, &cp->cp_flags),
SENDING);
/* XXX Future: return the state rather than these funky bits */
rds_conn_info_set(cinfo6->flags,
atomic_read(&cp->cp_state) == RDS_CONN_CONNECTING,
CONNECTING);
rds_conn_info_set(cinfo6->flags,
atomic_read(&cp->cp_state) == RDS_CONN_UP,
CONNECTED);
/* Just return 1 as there is no error case. This is a helper function
* for rds_walk_conn_path_info() and it wants a return value.
*/
return 1;
}
#endif
static void rds_conn_info(struct socket *sock, unsigned int len,
struct rds_info_iterator *iter,
struct rds_info_lengths *lens)
{
u64 buffer[(sizeof(struct rds_info_connection) + 7) / 8];
rds_walk_conn_path_info(sock, len, iter, lens,
rds_conn_info_visitor,
buffer,
sizeof(struct rds_info_connection));
}
#if IS_ENABLED(CONFIG_IPV6)
static void rds6_conn_info(struct socket *sock, unsigned int len,
struct rds_info_iterator *iter,
struct rds_info_lengths *lens)
{
u64 buffer[(sizeof(struct rds6_info_connection) + 7) / 8];
rds_walk_conn_path_info(sock, len, iter, lens,
rds6_conn_info_visitor,
buffer,
sizeof(struct rds6_info_connection));
}
#endif
int rds_conn_init(void)
{
int ret;
ret = rds_loop_net_init(); /* register pernet callback */
if (ret)
return ret;
rds_conn_slab = kmem_cache_create("rds_connection",
sizeof(struct rds_connection),
0, 0, NULL);
if (!rds_conn_slab) {
rds_loop_net_exit();
return -ENOMEM;
}
rds_info_register_func(RDS_INFO_CONNECTIONS, rds_conn_info);
rds_info_register_func(RDS_INFO_SEND_MESSAGES,
rds_conn_message_info_send);
rds_info_register_func(RDS_INFO_RETRANS_MESSAGES,
rds_conn_message_info_retrans);
#if IS_ENABLED(CONFIG_IPV6)
rds_info_register_func(RDS6_INFO_CONNECTIONS, rds6_conn_info);
rds_info_register_func(RDS6_INFO_SEND_MESSAGES,
rds6_conn_message_info_send);
rds_info_register_func(RDS6_INFO_RETRANS_MESSAGES,
rds6_conn_message_info_retrans);
#endif
return 0;
}
void rds_conn_exit(void)
{
rds_loop_net_exit(); /* unregister pernet callback */
rds_loop_exit();
WARN_ON(!hlist_empty(rds_conn_hash));
kmem_cache_destroy(rds_conn_slab);
rds_info_deregister_func(RDS_INFO_CONNECTIONS, rds_conn_info);
rds_info_deregister_func(RDS_INFO_SEND_MESSAGES,
rds_conn_message_info_send);
rds_info_deregister_func(RDS_INFO_RETRANS_MESSAGES,
rds_conn_message_info_retrans);
#if IS_ENABLED(CONFIG_IPV6)
rds_info_deregister_func(RDS6_INFO_CONNECTIONS, rds6_conn_info);
rds_info_deregister_func(RDS6_INFO_SEND_MESSAGES,
rds6_conn_message_info_send);
rds_info_deregister_func(RDS6_INFO_RETRANS_MESSAGES,
rds6_conn_message_info_retrans);
#endif
}
/*
* Force a disconnect
*/
void rds_conn_path_drop(struct rds_conn_path *cp, bool destroy)
{
atomic_set(&cp->cp_state, RDS_CONN_ERROR);
rcu_read_lock();
if (!destroy && rds_destroy_pending(cp->cp_conn)) {
rcu_read_unlock();
return;
}
queue_work(rds_wq, &cp->cp_down_w);
rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(rds_conn_path_drop);
void rds_conn_drop(struct rds_connection *conn)
{
WARN_ON(conn->c_trans->t_mp_capable);
rds_conn_path_drop(&conn->c_path[0], false);
}
EXPORT_SYMBOL_GPL(rds_conn_drop);
/*
* If the connection is down, trigger a connect. We may have scheduled a
* delayed reconnect however - in this case we should not interfere.
*/
void rds_conn_path_connect_if_down(struct rds_conn_path *cp)
{
rcu_read_lock();
if (rds_destroy_pending(cp->cp_conn)) {
rcu_read_unlock();
return;
}
if (rds_conn_path_state(cp) == RDS_CONN_DOWN &&
!test_and_set_bit(RDS_RECONNECT_PENDING, &cp->cp_flags))
queue_delayed_work(rds_wq, &cp->cp_conn_w, 0);
rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(rds_conn_path_connect_if_down);
/* Check connectivity of all paths
*/
void rds_check_all_paths(struct rds_connection *conn)
{
int i = 0;
do {
rds_conn_path_connect_if_down(&conn->c_path[i]);
} while (++i < conn->c_npaths);
}
void rds_conn_connect_if_down(struct rds_connection *conn)
{
WARN_ON(conn->c_trans->t_mp_capable);
rds_conn_path_connect_if_down(&conn->c_path[0]);
}
EXPORT_SYMBOL_GPL(rds_conn_connect_if_down);
void
__rds_conn_path_error(struct rds_conn_path *cp, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vprintk(fmt, ap);
va_end(ap);
rds_conn_path_drop(cp, false);
}