linux/net/smc/af_smc.c
Ursula Braun 51e3dfa890 net/smc: fix cleanup for linkgroup setup failures
If an SMC connection to a certain peer is setup the first time,
a new linkgroup is created. In case of setup failures, such a
linkgroup is unusable and should disappear. As a first step the
linkgroup is removed from the linkgroup list in smc_lgr_forget().

There are 2 problems:
smc_listen_decline() might be called before linkgroup creation
resulting in a crash due to calling smc_lgr_forget() with
parameter NULL.
If a setup failure occurs after linkgroup creation, the connection
is never unregistered from the linkgroup, preventing linkgroup
freeing.

This patch introduces an enhanced smc_lgr_cleanup_early() function
which
* contains a linkgroup check for early smc_listen_decline()
  invocations
* invokes smc_conn_free() to guarantee unregistering of the
  connection.
* schedules fast linkgroup removal of the unusable linkgroup

And the unused function smcd_conn_free() is removed from smc_core.h.

Fixes: 3b2dec2603 ("net/smc: restructure client and server code in af_smc")
Fixes: 2a0674fffb ("net/smc: improve abnormal termination of link groups")
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-26 20:18:07 -08:00

2135 lines
53 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Shared Memory Communications over RDMA (SMC-R) and RoCE
*
* AF_SMC protocol family socket handler keeping the AF_INET sock address type
* applies to SOCK_STREAM sockets only
* offers an alternative communication option for TCP-protocol sockets
* applicable with RoCE-cards only
*
* Initial restrictions:
* - support for alternate links postponed
*
* Copyright IBM Corp. 2016, 2018
*
* Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
* based on prototype from Frank Blaschka
*/
#define KMSG_COMPONENT "smc"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/module.h>
#include <linux/socket.h>
#include <linux/workqueue.h>
#include <linux/in.h>
#include <linux/sched/signal.h>
#include <linux/if_vlan.h>
#include <linux/rcupdate_wait.h>
#include <net/sock.h>
#include <net/tcp.h>
#include <net/smc.h>
#include <asm/ioctls.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include "smc_netns.h"
#include "smc.h"
#include "smc_clc.h"
#include "smc_llc.h"
#include "smc_cdc.h"
#include "smc_core.h"
#include "smc_ib.h"
#include "smc_ism.h"
#include "smc_pnet.h"
#include "smc_tx.h"
#include "smc_rx.h"
#include "smc_close.h"
static DEFINE_MUTEX(smc_server_lgr_pending); /* serialize link group
* creation on server
*/
static DEFINE_MUTEX(smc_client_lgr_pending); /* serialize link group
* creation on client
*/
static void smc_tcp_listen_work(struct work_struct *);
static void smc_connect_work(struct work_struct *);
static void smc_set_keepalive(struct sock *sk, int val)
{
struct smc_sock *smc = smc_sk(sk);
smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
}
static struct smc_hashinfo smc_v4_hashinfo = {
.lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
};
static struct smc_hashinfo smc_v6_hashinfo = {
.lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
};
int smc_hash_sk(struct sock *sk)
{
struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
struct hlist_head *head;
head = &h->ht;
write_lock_bh(&h->lock);
sk_add_node(sk, head);
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
write_unlock_bh(&h->lock);
return 0;
}
EXPORT_SYMBOL_GPL(smc_hash_sk);
void smc_unhash_sk(struct sock *sk)
{
struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
write_lock_bh(&h->lock);
if (sk_del_node_init(sk))
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
write_unlock_bh(&h->lock);
}
EXPORT_SYMBOL_GPL(smc_unhash_sk);
struct proto smc_proto = {
.name = "SMC",
.owner = THIS_MODULE,
.keepalive = smc_set_keepalive,
.hash = smc_hash_sk,
.unhash = smc_unhash_sk,
.obj_size = sizeof(struct smc_sock),
.h.smc_hash = &smc_v4_hashinfo,
.slab_flags = SLAB_TYPESAFE_BY_RCU,
};
EXPORT_SYMBOL_GPL(smc_proto);
struct proto smc_proto6 = {
.name = "SMC6",
.owner = THIS_MODULE,
.keepalive = smc_set_keepalive,
.hash = smc_hash_sk,
.unhash = smc_unhash_sk,
.obj_size = sizeof(struct smc_sock),
.h.smc_hash = &smc_v6_hashinfo,
.slab_flags = SLAB_TYPESAFE_BY_RCU,
};
EXPORT_SYMBOL_GPL(smc_proto6);
static void smc_restore_fallback_changes(struct smc_sock *smc)
{
smc->clcsock->file->private_data = smc->sk.sk_socket;
smc->clcsock->file = NULL;
}
static int __smc_release(struct smc_sock *smc)
{
struct sock *sk = &smc->sk;
int rc = 0;
if (!smc->use_fallback) {
rc = smc_close_active(smc);
sock_set_flag(sk, SOCK_DEAD);
sk->sk_shutdown |= SHUTDOWN_MASK;
} else {
if (sk->sk_state != SMC_LISTEN && sk->sk_state != SMC_INIT)
sock_put(sk); /* passive closing */
if (sk->sk_state == SMC_LISTEN) {
/* wake up clcsock accept */
rc = kernel_sock_shutdown(smc->clcsock, SHUT_RDWR);
}
sk->sk_state = SMC_CLOSED;
sk->sk_state_change(sk);
smc_restore_fallback_changes(smc);
}
sk->sk_prot->unhash(sk);
if (sk->sk_state == SMC_CLOSED) {
if (smc->clcsock) {
release_sock(sk);
smc_clcsock_release(smc);
lock_sock(sk);
}
if (!smc->use_fallback)
smc_conn_free(&smc->conn);
}
return rc;
}
static int smc_release(struct socket *sock)
{
struct sock *sk = sock->sk;
struct smc_sock *smc;
int rc = 0;
if (!sk)
goto out;
sock_hold(sk); /* sock_put below */
smc = smc_sk(sk);
/* cleanup for a dangling non-blocking connect */
if (smc->connect_nonblock && sk->sk_state == SMC_INIT)
tcp_abort(smc->clcsock->sk, ECONNABORTED);
flush_work(&smc->connect_work);
if (sk->sk_state == SMC_LISTEN)
/* smc_close_non_accepted() is called and acquires
* sock lock for child sockets again
*/
lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
else
lock_sock(sk);
rc = __smc_release(smc);
/* detach socket */
sock_orphan(sk);
sock->sk = NULL;
release_sock(sk);
sock_put(sk); /* sock_hold above */
sock_put(sk); /* final sock_put */
out:
return rc;
}
static void smc_destruct(struct sock *sk)
{
if (sk->sk_state != SMC_CLOSED)
return;
if (!sock_flag(sk, SOCK_DEAD))
return;
sk_refcnt_debug_dec(sk);
}
static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
int protocol)
{
struct smc_sock *smc;
struct proto *prot;
struct sock *sk;
prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
if (!sk)
return NULL;
sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
sk->sk_state = SMC_INIT;
sk->sk_destruct = smc_destruct;
sk->sk_protocol = protocol;
smc = smc_sk(sk);
INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
INIT_WORK(&smc->connect_work, smc_connect_work);
INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
INIT_LIST_HEAD(&smc->accept_q);
spin_lock_init(&smc->accept_q_lock);
spin_lock_init(&smc->conn.send_lock);
sk->sk_prot->hash(sk);
sk_refcnt_debug_inc(sk);
mutex_init(&smc->clcsock_release_lock);
return sk;
}
static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
int addr_len)
{
struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
struct sock *sk = sock->sk;
struct smc_sock *smc;
int rc;
smc = smc_sk(sk);
/* replicate tests from inet_bind(), to be safe wrt. future changes */
rc = -EINVAL;
if (addr_len < sizeof(struct sockaddr_in))
goto out;
rc = -EAFNOSUPPORT;
if (addr->sin_family != AF_INET &&
addr->sin_family != AF_INET6 &&
addr->sin_family != AF_UNSPEC)
goto out;
/* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
if (addr->sin_family == AF_UNSPEC &&
addr->sin_addr.s_addr != htonl(INADDR_ANY))
goto out;
lock_sock(sk);
/* Check if socket is already active */
rc = -EINVAL;
if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
goto out_rel;
smc->clcsock->sk->sk_reuse = sk->sk_reuse;
rc = kernel_bind(smc->clcsock, uaddr, addr_len);
out_rel:
release_sock(sk);
out:
return rc;
}
static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
unsigned long mask)
{
/* options we don't get control via setsockopt for */
nsk->sk_type = osk->sk_type;
nsk->sk_sndbuf = osk->sk_sndbuf;
nsk->sk_rcvbuf = osk->sk_rcvbuf;
nsk->sk_sndtimeo = osk->sk_sndtimeo;
nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
nsk->sk_mark = osk->sk_mark;
nsk->sk_priority = osk->sk_priority;
nsk->sk_rcvlowat = osk->sk_rcvlowat;
nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
nsk->sk_err = osk->sk_err;
nsk->sk_flags &= ~mask;
nsk->sk_flags |= osk->sk_flags & mask;
}
#define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
(1UL << SOCK_KEEPOPEN) | \
(1UL << SOCK_LINGER) | \
(1UL << SOCK_BROADCAST) | \
(1UL << SOCK_TIMESTAMP) | \
(1UL << SOCK_DBG) | \
(1UL << SOCK_RCVTSTAMP) | \
(1UL << SOCK_RCVTSTAMPNS) | \
(1UL << SOCK_LOCALROUTE) | \
(1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
(1UL << SOCK_RXQ_OVFL) | \
(1UL << SOCK_WIFI_STATUS) | \
(1UL << SOCK_NOFCS) | \
(1UL << SOCK_FILTER_LOCKED) | \
(1UL << SOCK_TSTAMP_NEW))
/* copy only relevant settings and flags of SOL_SOCKET level from smc to
* clc socket (since smc is not called for these options from net/core)
*/
static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
{
smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
}
#define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
(1UL << SOCK_KEEPOPEN) | \
(1UL << SOCK_LINGER) | \
(1UL << SOCK_DBG))
/* copy only settings and flags relevant for smc from clc to smc socket */
static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
{
smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
}
/* register a new rmb, send confirm_rkey msg to register with peer */
static int smc_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc,
bool conf_rkey)
{
if (!rmb_desc->wr_reg) {
/* register memory region for new rmb */
if (smc_wr_reg_send(link, rmb_desc->mr_rx[SMC_SINGLE_LINK])) {
rmb_desc->regerr = 1;
return -EFAULT;
}
rmb_desc->wr_reg = 1;
}
if (!conf_rkey)
return 0;
/* exchange confirm_rkey msg with peer */
if (smc_llc_do_confirm_rkey(link, rmb_desc)) {
rmb_desc->regerr = 1;
return -EFAULT;
}
return 0;
}
static int smc_clnt_conf_first_link(struct smc_sock *smc)
{
struct net *net = sock_net(smc->clcsock->sk);
struct smc_link_group *lgr = smc->conn.lgr;
struct smc_link *link;
int rest;
int rc;
link = &lgr->lnk[SMC_SINGLE_LINK];
/* receive CONFIRM LINK request from server over RoCE fabric */
rest = wait_for_completion_interruptible_timeout(
&link->llc_confirm,
SMC_LLC_WAIT_FIRST_TIME);
if (rest <= 0) {
struct smc_clc_msg_decline dclc;
rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
}
if (link->llc_confirm_rc)
return SMC_CLC_DECL_RMBE_EC;
rc = smc_ib_modify_qp_rts(link);
if (rc)
return SMC_CLC_DECL_ERR_RDYLNK;
smc_wr_remember_qp_attr(link);
if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
return SMC_CLC_DECL_ERR_REGRMB;
/* send CONFIRM LINK response over RoCE fabric */
rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
if (rc < 0)
return SMC_CLC_DECL_TIMEOUT_CL;
/* receive ADD LINK request from server over RoCE fabric */
rest = wait_for_completion_interruptible_timeout(&link->llc_add,
SMC_LLC_WAIT_TIME);
if (rest <= 0) {
struct smc_clc_msg_decline dclc;
rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_AL : rc;
}
/* send add link reject message, only one link supported for now */
rc = smc_llc_send_add_link(link,
link->smcibdev->mac[link->ibport - 1],
link->gid, SMC_LLC_RESP);
if (rc < 0)
return SMC_CLC_DECL_TIMEOUT_AL;
smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
return 0;
}
static void smcr_conn_save_peer_info(struct smc_sock *smc,
struct smc_clc_msg_accept_confirm *clc)
{
int bufsize = smc_uncompress_bufsize(clc->rmbe_size);
smc->conn.peer_rmbe_idx = clc->rmbe_idx;
smc->conn.local_tx_ctrl.token = ntohl(clc->rmbe_alert_token);
smc->conn.peer_rmbe_size = bufsize;
atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
}
static void smcd_conn_save_peer_info(struct smc_sock *smc,
struct smc_clc_msg_accept_confirm *clc)
{
int bufsize = smc_uncompress_bufsize(clc->dmbe_size);
smc->conn.peer_rmbe_idx = clc->dmbe_idx;
smc->conn.peer_token = clc->token;
/* msg header takes up space in the buffer */
smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
}
static void smc_conn_save_peer_info(struct smc_sock *smc,
struct smc_clc_msg_accept_confirm *clc)
{
if (smc->conn.lgr->is_smcd)
smcd_conn_save_peer_info(smc, clc);
else
smcr_conn_save_peer_info(smc, clc);
}
static void smc_link_save_peer_info(struct smc_link *link,
struct smc_clc_msg_accept_confirm *clc)
{
link->peer_qpn = ntoh24(clc->qpn);
memcpy(link->peer_gid, clc->lcl.gid, SMC_GID_SIZE);
memcpy(link->peer_mac, clc->lcl.mac, sizeof(link->peer_mac));
link->peer_psn = ntoh24(clc->psn);
link->peer_mtu = clc->qp_mtu;
}
static void smc_switch_to_fallback(struct smc_sock *smc)
{
smc->use_fallback = true;
if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
smc->clcsock->file = smc->sk.sk_socket->file;
smc->clcsock->file->private_data = smc->clcsock;
smc->clcsock->wq.fasync_list =
smc->sk.sk_socket->wq.fasync_list;
}
}
/* fall back during connect */
static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
{
smc_switch_to_fallback(smc);
smc->fallback_rsn = reason_code;
smc_copy_sock_settings_to_clc(smc);
smc->connect_nonblock = 0;
if (smc->sk.sk_state == SMC_INIT)
smc->sk.sk_state = SMC_ACTIVE;
return 0;
}
/* decline and fall back during connect */
static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code)
{
int rc;
if (reason_code < 0) { /* error, fallback is not possible */
if (smc->sk.sk_state == SMC_INIT)
sock_put(&smc->sk); /* passive closing */
return reason_code;
}
if (reason_code != SMC_CLC_DECL_PEERDECL) {
rc = smc_clc_send_decline(smc, reason_code);
if (rc < 0) {
if (smc->sk.sk_state == SMC_INIT)
sock_put(&smc->sk); /* passive closing */
return rc;
}
}
return smc_connect_fallback(smc, reason_code);
}
/* abort connecting */
static int smc_connect_abort(struct smc_sock *smc, int reason_code,
int local_contact)
{
bool is_smcd = smc->conn.lgr->is_smcd;
if (local_contact == SMC_FIRST_CONTACT)
smc_lgr_cleanup_early(&smc->conn);
else
smc_conn_free(&smc->conn);
if (is_smcd)
/* there is only one lgr role for SMC-D; use server lock */
mutex_unlock(&smc_server_lgr_pending);
else
mutex_unlock(&smc_client_lgr_pending);
smc->connect_nonblock = 0;
return reason_code;
}
/* check if there is a rdma device available for this connection. */
/* called for connect and listen */
static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
{
/* PNET table look up: search active ib_device and port
* within same PNETID that also contains the ethernet device
* used for the internal TCP socket
*/
smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
if (!ini->ib_dev)
return SMC_CLC_DECL_NOSMCRDEV;
return 0;
}
/* check if there is an ISM device available for this connection. */
/* called for connect and listen */
static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
{
/* Find ISM device with same PNETID as connecting interface */
smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
if (!ini->ism_dev)
return SMC_CLC_DECL_NOSMCDDEV;
return 0;
}
/* Check for VLAN ID and register it on ISM device just for CLC handshake */
static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
struct smc_init_info *ini)
{
if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev, ini->vlan_id))
return SMC_CLC_DECL_ISMVLANERR;
return 0;
}
/* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
* used, the VLAN ID will be registered again during the connection setup.
*/
static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc, bool is_smcd,
struct smc_init_info *ini)
{
if (!is_smcd)
return 0;
if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev, ini->vlan_id))
return SMC_CLC_DECL_CNFERR;
return 0;
}
/* CLC handshake during connect */
static int smc_connect_clc(struct smc_sock *smc, int smc_type,
struct smc_clc_msg_accept_confirm *aclc,
struct smc_init_info *ini)
{
int rc = 0;
/* do inband token exchange */
rc = smc_clc_send_proposal(smc, smc_type, ini);
if (rc)
return rc;
/* receive SMC Accept CLC message */
return smc_clc_wait_msg(smc, aclc, sizeof(*aclc), SMC_CLC_ACCEPT,
CLC_WAIT_TIME);
}
/* setup for RDMA connection of client */
static int smc_connect_rdma(struct smc_sock *smc,
struct smc_clc_msg_accept_confirm *aclc,
struct smc_init_info *ini)
{
struct smc_link *link;
int reason_code = 0;
ini->is_smcd = false;
ini->ib_lcl = &aclc->lcl;
ini->ib_clcqpn = ntoh24(aclc->qpn);
ini->srv_first_contact = aclc->hdr.flag;
mutex_lock(&smc_client_lgr_pending);
reason_code = smc_conn_create(smc, ini);
if (reason_code) {
mutex_unlock(&smc_client_lgr_pending);
return reason_code;
}
link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK];
smc_conn_save_peer_info(smc, aclc);
/* create send buffer and rmb */
if (smc_buf_create(smc, false))
return smc_connect_abort(smc, SMC_CLC_DECL_MEM,
ini->cln_first_contact);
if (ini->cln_first_contact == SMC_FIRST_CONTACT)
smc_link_save_peer_info(link, aclc);
if (smc_rmb_rtoken_handling(&smc->conn, aclc))
return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RTOK,
ini->cln_first_contact);
smc_close_init(smc);
smc_rx_init(smc);
if (ini->cln_first_contact == SMC_FIRST_CONTACT) {
if (smc_ib_ready_link(link))
return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RDYLNK,
ini->cln_first_contact);
} else {
if (smc_reg_rmb(link, smc->conn.rmb_desc, true))
return smc_connect_abort(smc, SMC_CLC_DECL_ERR_REGRMB,
ini->cln_first_contact);
}
smc_rmb_sync_sg_for_device(&smc->conn);
reason_code = smc_clc_send_confirm(smc);
if (reason_code)
return smc_connect_abort(smc, reason_code,
ini->cln_first_contact);
smc_tx_init(smc);
if (ini->cln_first_contact == SMC_FIRST_CONTACT) {
/* QP confirmation over RoCE fabric */
reason_code = smc_clnt_conf_first_link(smc);
if (reason_code)
return smc_connect_abort(smc, reason_code,
ini->cln_first_contact);
}
mutex_unlock(&smc_client_lgr_pending);
smc_copy_sock_settings_to_clc(smc);
smc->connect_nonblock = 0;
if (smc->sk.sk_state == SMC_INIT)
smc->sk.sk_state = SMC_ACTIVE;
return 0;
}
/* setup for ISM connection of client */
static int smc_connect_ism(struct smc_sock *smc,
struct smc_clc_msg_accept_confirm *aclc,
struct smc_init_info *ini)
{
int rc = 0;
ini->is_smcd = true;
ini->ism_gid = aclc->gid;
ini->srv_first_contact = aclc->hdr.flag;
/* there is only one lgr role for SMC-D; use server lock */
mutex_lock(&smc_server_lgr_pending);
rc = smc_conn_create(smc, ini);
if (rc) {
mutex_unlock(&smc_server_lgr_pending);
return rc;
}
/* Create send and receive buffers */
if (smc_buf_create(smc, true))
return smc_connect_abort(smc, SMC_CLC_DECL_MEM,
ini->cln_first_contact);
smc_conn_save_peer_info(smc, aclc);
smc_close_init(smc);
smc_rx_init(smc);
smc_tx_init(smc);
rc = smc_clc_send_confirm(smc);
if (rc)
return smc_connect_abort(smc, rc, ini->cln_first_contact);
mutex_unlock(&smc_server_lgr_pending);
smc_copy_sock_settings_to_clc(smc);
smc->connect_nonblock = 0;
if (smc->sk.sk_state == SMC_INIT)
smc->sk.sk_state = SMC_ACTIVE;
return 0;
}
/* perform steps before actually connecting */
static int __smc_connect(struct smc_sock *smc)
{
bool ism_supported = false, rdma_supported = false;
struct smc_clc_msg_accept_confirm aclc;
struct smc_init_info ini = {0};
int smc_type;
int rc = 0;
if (smc->use_fallback)
return smc_connect_fallback(smc, smc->fallback_rsn);
/* if peer has not signalled SMC-capability, fall back */
if (!tcp_sk(smc->clcsock->sk)->syn_smc)
return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
/* IPSec connections opt out of SMC-R optimizations */
if (using_ipsec(smc))
return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC);
/* get vlan id from IP device */
if (smc_vlan_by_tcpsk(smc->clcsock, &ini))
return smc_connect_decline_fallback(smc,
SMC_CLC_DECL_GETVLANERR);
/* check if there is an ism device available */
if (!smc_find_ism_device(smc, &ini) &&
!smc_connect_ism_vlan_setup(smc, &ini)) {
/* ISM is supported for this connection */
ism_supported = true;
smc_type = SMC_TYPE_D;
}
/* check if there is a rdma device available */
if (!smc_find_rdma_device(smc, &ini)) {
/* RDMA is supported for this connection */
rdma_supported = true;
if (ism_supported)
smc_type = SMC_TYPE_B; /* both */
else
smc_type = SMC_TYPE_R; /* only RDMA */
}
/* if neither ISM nor RDMA are supported, fallback */
if (!rdma_supported && !ism_supported)
return smc_connect_decline_fallback(smc, SMC_CLC_DECL_NOSMCDEV);
/* perform CLC handshake */
rc = smc_connect_clc(smc, smc_type, &aclc, &ini);
if (rc) {
smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
return smc_connect_decline_fallback(smc, rc);
}
/* depending on previous steps, connect using rdma or ism */
if (rdma_supported && aclc.hdr.path == SMC_TYPE_R)
rc = smc_connect_rdma(smc, &aclc, &ini);
else if (ism_supported && aclc.hdr.path == SMC_TYPE_D)
rc = smc_connect_ism(smc, &aclc, &ini);
else
rc = SMC_CLC_DECL_MODEUNSUPP;
if (rc) {
smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
return smc_connect_decline_fallback(smc, rc);
}
smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
return 0;
}
static void smc_connect_work(struct work_struct *work)
{
struct smc_sock *smc = container_of(work, struct smc_sock,
connect_work);
long timeo = smc->sk.sk_sndtimeo;
int rc = 0;
if (!timeo)
timeo = MAX_SCHEDULE_TIMEOUT;
lock_sock(smc->clcsock->sk);
if (smc->clcsock->sk->sk_err) {
smc->sk.sk_err = smc->clcsock->sk->sk_err;
} else if ((1 << smc->clcsock->sk->sk_state) &
(TCPF_SYN_SENT | TCP_SYN_RECV)) {
rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
if ((rc == -EPIPE) &&
((1 << smc->clcsock->sk->sk_state) &
(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
rc = 0;
}
release_sock(smc->clcsock->sk);
lock_sock(&smc->sk);
if (rc != 0 || smc->sk.sk_err) {
smc->sk.sk_state = SMC_CLOSED;
if (rc == -EPIPE || rc == -EAGAIN)
smc->sk.sk_err = EPIPE;
else if (signal_pending(current))
smc->sk.sk_err = -sock_intr_errno(timeo);
sock_put(&smc->sk); /* passive closing */
goto out;
}
rc = __smc_connect(smc);
if (rc < 0)
smc->sk.sk_err = -rc;
out:
if (!sock_flag(&smc->sk, SOCK_DEAD)) {
if (smc->sk.sk_err) {
smc->sk.sk_state_change(&smc->sk);
} else { /* allow polling before and after fallback decision */
smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
smc->sk.sk_write_space(&smc->sk);
}
}
release_sock(&smc->sk);
}
static int smc_connect(struct socket *sock, struct sockaddr *addr,
int alen, int flags)
{
struct sock *sk = sock->sk;
struct smc_sock *smc;
int rc = -EINVAL;
smc = smc_sk(sk);
/* separate smc parameter checking to be safe */
if (alen < sizeof(addr->sa_family))
goto out_err;
if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
goto out_err;
lock_sock(sk);
switch (sk->sk_state) {
default:
goto out;
case SMC_ACTIVE:
rc = -EISCONN;
goto out;
case SMC_INIT:
rc = 0;
break;
}
smc_copy_sock_settings_to_clc(smc);
tcp_sk(smc->clcsock->sk)->syn_smc = 1;
if (smc->connect_nonblock) {
rc = -EALREADY;
goto out;
}
rc = kernel_connect(smc->clcsock, addr, alen, flags);
if (rc && rc != -EINPROGRESS)
goto out;
sock_hold(&smc->sk); /* sock put in passive closing */
if (smc->use_fallback)
goto out;
if (flags & O_NONBLOCK) {
if (schedule_work(&smc->connect_work))
smc->connect_nonblock = 1;
rc = -EINPROGRESS;
} else {
rc = __smc_connect(smc);
if (rc < 0)
goto out;
else
rc = 0; /* success cases including fallback */
}
out:
release_sock(sk);
out_err:
return rc;
}
static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
{
struct socket *new_clcsock = NULL;
struct sock *lsk = &lsmc->sk;
struct sock *new_sk;
int rc = -EINVAL;
release_sock(lsk);
new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
if (!new_sk) {
rc = -ENOMEM;
lsk->sk_err = ENOMEM;
*new_smc = NULL;
lock_sock(lsk);
goto out;
}
*new_smc = smc_sk(new_sk);
mutex_lock(&lsmc->clcsock_release_lock);
if (lsmc->clcsock)
rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0);
mutex_unlock(&lsmc->clcsock_release_lock);
lock_sock(lsk);
if (rc < 0)
lsk->sk_err = -rc;
if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
new_sk->sk_prot->unhash(new_sk);
if (new_clcsock)
sock_release(new_clcsock);
new_sk->sk_state = SMC_CLOSED;
sock_set_flag(new_sk, SOCK_DEAD);
sock_put(new_sk); /* final */
*new_smc = NULL;
goto out;
}
(*new_smc)->clcsock = new_clcsock;
out:
return rc;
}
/* add a just created sock to the accept queue of the listen sock as
* candidate for a following socket accept call from user space
*/
static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
{
struct smc_sock *par = smc_sk(parent);
sock_hold(sk); /* sock_put in smc_accept_unlink () */
spin_lock(&par->accept_q_lock);
list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
spin_unlock(&par->accept_q_lock);
sk_acceptq_added(parent);
}
/* remove a socket from the accept queue of its parental listening socket */
static void smc_accept_unlink(struct sock *sk)
{
struct smc_sock *par = smc_sk(sk)->listen_smc;
spin_lock(&par->accept_q_lock);
list_del_init(&smc_sk(sk)->accept_q);
spin_unlock(&par->accept_q_lock);
sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
sock_put(sk); /* sock_hold in smc_accept_enqueue */
}
/* remove a sock from the accept queue to bind it to a new socket created
* for a socket accept call from user space
*/
struct sock *smc_accept_dequeue(struct sock *parent,
struct socket *new_sock)
{
struct smc_sock *isk, *n;
struct sock *new_sk;
list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
new_sk = (struct sock *)isk;
smc_accept_unlink(new_sk);
if (new_sk->sk_state == SMC_CLOSED) {
new_sk->sk_prot->unhash(new_sk);
if (isk->clcsock) {
sock_release(isk->clcsock);
isk->clcsock = NULL;
}
sock_put(new_sk); /* final */
continue;
}
if (new_sock) {
sock_graft(new_sk, new_sock);
if (isk->use_fallback) {
smc_sk(new_sk)->clcsock->file = new_sock->file;
isk->clcsock->file->private_data = isk->clcsock;
}
}
return new_sk;
}
return NULL;
}
/* clean up for a created but never accepted sock */
void smc_close_non_accepted(struct sock *sk)
{
struct smc_sock *smc = smc_sk(sk);
sock_hold(sk); /* sock_put below */
lock_sock(sk);
if (!sk->sk_lingertime)
/* wait for peer closing */
sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
__smc_release(smc);
release_sock(sk);
sock_put(sk); /* sock_hold above */
sock_put(sk); /* final sock_put */
}
static int smc_serv_conf_first_link(struct smc_sock *smc)
{
struct net *net = sock_net(smc->clcsock->sk);
struct smc_link_group *lgr = smc->conn.lgr;
struct smc_link *link;
int rest;
int rc;
link = &lgr->lnk[SMC_SINGLE_LINK];
if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
return SMC_CLC_DECL_ERR_REGRMB;
/* send CONFIRM LINK request to client over the RoCE fabric */
rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
if (rc < 0)
return SMC_CLC_DECL_TIMEOUT_CL;
/* receive CONFIRM LINK response from client over the RoCE fabric */
rest = wait_for_completion_interruptible_timeout(
&link->llc_confirm_resp,
SMC_LLC_WAIT_FIRST_TIME);
if (rest <= 0) {
struct smc_clc_msg_decline dclc;
rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
}
if (link->llc_confirm_resp_rc)
return SMC_CLC_DECL_RMBE_EC;
/* send ADD LINK request to client over the RoCE fabric */
rc = smc_llc_send_add_link(link,
link->smcibdev->mac[link->ibport - 1],
link->gid, SMC_LLC_REQ);
if (rc < 0)
return SMC_CLC_DECL_TIMEOUT_AL;
/* receive ADD LINK response from client over the RoCE fabric */
rest = wait_for_completion_interruptible_timeout(&link->llc_add_resp,
SMC_LLC_WAIT_TIME);
if (rest <= 0) {
struct smc_clc_msg_decline dclc;
rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_AL : rc;
}
smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
return 0;
}
/* listen worker: finish */
static void smc_listen_out(struct smc_sock *new_smc)
{
struct smc_sock *lsmc = new_smc->listen_smc;
struct sock *newsmcsk = &new_smc->sk;
if (lsmc->sk.sk_state == SMC_LISTEN) {
lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
smc_accept_enqueue(&lsmc->sk, newsmcsk);
release_sock(&lsmc->sk);
} else { /* no longer listening */
smc_close_non_accepted(newsmcsk);
}
/* Wake up accept */
lsmc->sk.sk_data_ready(&lsmc->sk);
sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
}
/* listen worker: finish in state connected */
static void smc_listen_out_connected(struct smc_sock *new_smc)
{
struct sock *newsmcsk = &new_smc->sk;
sk_refcnt_debug_inc(newsmcsk);
if (newsmcsk->sk_state == SMC_INIT)
newsmcsk->sk_state = SMC_ACTIVE;
smc_listen_out(new_smc);
}
/* listen worker: finish in error state */
static void smc_listen_out_err(struct smc_sock *new_smc)
{
struct sock *newsmcsk = &new_smc->sk;
if (newsmcsk->sk_state == SMC_INIT)
sock_put(&new_smc->sk); /* passive closing */
newsmcsk->sk_state = SMC_CLOSED;
smc_listen_out(new_smc);
}
/* listen worker: decline and fall back if possible */
static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
int local_contact)
{
/* RDMA setup failed, switch back to TCP */
if (local_contact == SMC_FIRST_CONTACT)
smc_lgr_cleanup_early(&new_smc->conn);
else
smc_conn_free(&new_smc->conn);
if (reason_code < 0) { /* error, no fallback possible */
smc_listen_out_err(new_smc);
return;
}
smc_switch_to_fallback(new_smc);
new_smc->fallback_rsn = reason_code;
if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
if (smc_clc_send_decline(new_smc, reason_code) < 0) {
smc_listen_out_err(new_smc);
return;
}
}
smc_listen_out_connected(new_smc);
}
/* listen worker: check prefixes */
static int smc_listen_prfx_check(struct smc_sock *new_smc,
struct smc_clc_msg_proposal *pclc)
{
struct smc_clc_msg_proposal_prefix *pclc_prfx;
struct socket *newclcsock = new_smc->clcsock;
pclc_prfx = smc_clc_proposal_get_prefix(pclc);
if (smc_clc_prfx_match(newclcsock, pclc_prfx))
return SMC_CLC_DECL_DIFFPREFIX;
return 0;
}
/* listen worker: initialize connection and buffers */
static int smc_listen_rdma_init(struct smc_sock *new_smc,
struct smc_init_info *ini)
{
int rc;
/* allocate connection / link group */
rc = smc_conn_create(new_smc, ini);
if (rc)
return rc;
/* create send buffer and rmb */
if (smc_buf_create(new_smc, false))
return SMC_CLC_DECL_MEM;
return 0;
}
/* listen worker: initialize connection and buffers for SMC-D */
static int smc_listen_ism_init(struct smc_sock *new_smc,
struct smc_clc_msg_proposal *pclc,
struct smc_init_info *ini)
{
struct smc_clc_msg_smcd *pclc_smcd;
int rc;
pclc_smcd = smc_get_clc_msg_smcd(pclc);
ini->ism_gid = pclc_smcd->gid;
rc = smc_conn_create(new_smc, ini);
if (rc)
return rc;
/* Check if peer can be reached via ISM device */
if (smc_ism_cantalk(new_smc->conn.lgr->peer_gid,
new_smc->conn.lgr->vlan_id,
new_smc->conn.lgr->smcd)) {
if (ini->cln_first_contact == SMC_FIRST_CONTACT)
smc_lgr_cleanup_early(&new_smc->conn);
else
smc_conn_free(&new_smc->conn);
return SMC_CLC_DECL_SMCDNOTALK;
}
/* Create send and receive buffers */
if (smc_buf_create(new_smc, true)) {
if (ini->cln_first_contact == SMC_FIRST_CONTACT)
smc_lgr_cleanup_early(&new_smc->conn);
else
smc_conn_free(&new_smc->conn);
return SMC_CLC_DECL_MEM;
}
return 0;
}
/* listen worker: register buffers */
static int smc_listen_rdma_reg(struct smc_sock *new_smc, int local_contact)
{
struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
if (local_contact != SMC_FIRST_CONTACT) {
if (smc_reg_rmb(link, new_smc->conn.rmb_desc, true))
return SMC_CLC_DECL_ERR_REGRMB;
}
smc_rmb_sync_sg_for_device(&new_smc->conn);
return 0;
}
/* listen worker: finish RDMA setup */
static int smc_listen_rdma_finish(struct smc_sock *new_smc,
struct smc_clc_msg_accept_confirm *cclc,
int local_contact)
{
struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
int reason_code = 0;
if (local_contact == SMC_FIRST_CONTACT)
smc_link_save_peer_info(link, cclc);
if (smc_rmb_rtoken_handling(&new_smc->conn, cclc)) {
reason_code = SMC_CLC_DECL_ERR_RTOK;
goto decline;
}
if (local_contact == SMC_FIRST_CONTACT) {
if (smc_ib_ready_link(link)) {
reason_code = SMC_CLC_DECL_ERR_RDYLNK;
goto decline;
}
/* QP confirmation over RoCE fabric */
reason_code = smc_serv_conf_first_link(new_smc);
if (reason_code)
goto decline;
}
return 0;
decline:
smc_listen_decline(new_smc, reason_code, local_contact);
return reason_code;
}
/* setup for RDMA connection of server */
static void smc_listen_work(struct work_struct *work)
{
struct smc_sock *new_smc = container_of(work, struct smc_sock,
smc_listen_work);
struct socket *newclcsock = new_smc->clcsock;
struct smc_clc_msg_accept_confirm cclc;
struct smc_clc_msg_proposal *pclc;
struct smc_init_info ini = {0};
bool ism_supported = false;
u8 buf[SMC_CLC_MAX_LEN];
int rc = 0;
if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
return smc_listen_out_err(new_smc);
if (new_smc->use_fallback) {
smc_listen_out_connected(new_smc);
return;
}
/* check if peer is smc capable */
if (!tcp_sk(newclcsock->sk)->syn_smc) {
smc_switch_to_fallback(new_smc);
new_smc->fallback_rsn = SMC_CLC_DECL_PEERNOSMC;
smc_listen_out_connected(new_smc);
return;
}
/* do inband token exchange -
* wait for and receive SMC Proposal CLC message
*/
pclc = (struct smc_clc_msg_proposal *)&buf;
rc = smc_clc_wait_msg(new_smc, pclc, SMC_CLC_MAX_LEN,
SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
if (rc)
goto out_decl;
/* IPSec connections opt out of SMC-R optimizations */
if (using_ipsec(new_smc)) {
rc = SMC_CLC_DECL_IPSEC;
goto out_decl;
}
/* check for matching IP prefix and subnet length */
rc = smc_listen_prfx_check(new_smc, pclc);
if (rc)
goto out_decl;
/* get vlan id from IP device */
if (smc_vlan_by_tcpsk(new_smc->clcsock, &ini)) {
rc = SMC_CLC_DECL_GETVLANERR;
goto out_decl;
}
mutex_lock(&smc_server_lgr_pending);
smc_close_init(new_smc);
smc_rx_init(new_smc);
smc_tx_init(new_smc);
/* check if ISM is available */
if (pclc->hdr.path == SMC_TYPE_D || pclc->hdr.path == SMC_TYPE_B) {
ini.is_smcd = true; /* prepare ISM check */
rc = smc_find_ism_device(new_smc, &ini);
if (!rc)
rc = smc_listen_ism_init(new_smc, pclc, &ini);
if (!rc)
ism_supported = true;
else if (pclc->hdr.path == SMC_TYPE_D)
goto out_unlock; /* skip RDMA and decline */
}
/* check if RDMA is available */
if (!ism_supported) { /* SMC_TYPE_R or SMC_TYPE_B */
/* prepare RDMA check */
ini.is_smcd = false;
ini.ism_dev = NULL;
ini.ib_lcl = &pclc->lcl;
rc = smc_find_rdma_device(new_smc, &ini);
if (rc) {
/* no RDMA device found */
if (pclc->hdr.path == SMC_TYPE_B)
/* neither ISM nor RDMA device found */
rc = SMC_CLC_DECL_NOSMCDEV;
goto out_unlock;
}
rc = smc_listen_rdma_init(new_smc, &ini);
if (rc)
goto out_unlock;
rc = smc_listen_rdma_reg(new_smc, ini.cln_first_contact);
if (rc)
goto out_unlock;
}
/* send SMC Accept CLC message */
rc = smc_clc_send_accept(new_smc, ini.cln_first_contact);
if (rc)
goto out_unlock;
/* SMC-D does not need this lock any more */
if (ism_supported)
mutex_unlock(&smc_server_lgr_pending);
/* receive SMC Confirm CLC message */
rc = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc),
SMC_CLC_CONFIRM, CLC_WAIT_TIME);
if (rc) {
if (!ism_supported)
goto out_unlock;
goto out_decl;
}
/* finish worker */
if (!ism_supported) {
rc = smc_listen_rdma_finish(new_smc, &cclc,
ini.cln_first_contact);
mutex_unlock(&smc_server_lgr_pending);
if (rc)
return;
}
smc_conn_save_peer_info(new_smc, &cclc);
smc_listen_out_connected(new_smc);
return;
out_unlock:
mutex_unlock(&smc_server_lgr_pending);
out_decl:
smc_listen_decline(new_smc, rc, ini.cln_first_contact);
}
static void smc_tcp_listen_work(struct work_struct *work)
{
struct smc_sock *lsmc = container_of(work, struct smc_sock,
tcp_listen_work);
struct sock *lsk = &lsmc->sk;
struct smc_sock *new_smc;
int rc = 0;
lock_sock(lsk);
while (lsk->sk_state == SMC_LISTEN) {
rc = smc_clcsock_accept(lsmc, &new_smc);
if (rc)
goto out;
if (!new_smc)
continue;
new_smc->listen_smc = lsmc;
new_smc->use_fallback = lsmc->use_fallback;
new_smc->fallback_rsn = lsmc->fallback_rsn;
sock_hold(lsk); /* sock_put in smc_listen_work */
INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
smc_copy_sock_settings_to_smc(new_smc);
new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf;
new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf;
sock_hold(&new_smc->sk); /* sock_put in passive closing */
if (!schedule_work(&new_smc->smc_listen_work))
sock_put(&new_smc->sk);
}
out:
release_sock(lsk);
sock_put(&lsmc->sk); /* sock_hold in smc_listen */
}
static int smc_listen(struct socket *sock, int backlog)
{
struct sock *sk = sock->sk;
struct smc_sock *smc;
int rc;
smc = smc_sk(sk);
lock_sock(sk);
rc = -EINVAL;
if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
smc->connect_nonblock)
goto out;
rc = 0;
if (sk->sk_state == SMC_LISTEN) {
sk->sk_max_ack_backlog = backlog;
goto out;
}
/* some socket options are handled in core, so we could not apply
* them to the clc socket -- copy smc socket options to clc socket
*/
smc_copy_sock_settings_to_clc(smc);
if (!smc->use_fallback)
tcp_sk(smc->clcsock->sk)->syn_smc = 1;
rc = kernel_listen(smc->clcsock, backlog);
if (rc)
goto out;
sk->sk_max_ack_backlog = backlog;
sk->sk_ack_backlog = 0;
sk->sk_state = SMC_LISTEN;
sock_hold(sk); /* sock_hold in tcp_listen_worker */
if (!schedule_work(&smc->tcp_listen_work))
sock_put(sk);
out:
release_sock(sk);
return rc;
}
static int smc_accept(struct socket *sock, struct socket *new_sock,
int flags, bool kern)
{
struct sock *sk = sock->sk, *nsk;
DECLARE_WAITQUEUE(wait, current);
struct smc_sock *lsmc;
long timeo;
int rc = 0;
lsmc = smc_sk(sk);
sock_hold(sk); /* sock_put below */
lock_sock(sk);
if (lsmc->sk.sk_state != SMC_LISTEN) {
rc = -EINVAL;
release_sock(sk);
goto out;
}
/* Wait for an incoming connection */
timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
add_wait_queue_exclusive(sk_sleep(sk), &wait);
while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
set_current_state(TASK_INTERRUPTIBLE);
if (!timeo) {
rc = -EAGAIN;
break;
}
release_sock(sk);
timeo = schedule_timeout(timeo);
/* wakeup by sk_data_ready in smc_listen_work() */
sched_annotate_sleep();
lock_sock(sk);
if (signal_pending(current)) {
rc = sock_intr_errno(timeo);
break;
}
}
set_current_state(TASK_RUNNING);
remove_wait_queue(sk_sleep(sk), &wait);
if (!rc)
rc = sock_error(nsk);
release_sock(sk);
if (rc)
goto out;
if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
/* wait till data arrives on the socket */
timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
MSEC_PER_SEC);
if (smc_sk(nsk)->use_fallback) {
struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
lock_sock(clcsk);
if (skb_queue_empty(&clcsk->sk_receive_queue))
sk_wait_data(clcsk, &timeo, NULL);
release_sock(clcsk);
} else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
lock_sock(nsk);
smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
release_sock(nsk);
}
}
out:
sock_put(sk); /* sock_hold above */
return rc;
}
static int smc_getname(struct socket *sock, struct sockaddr *addr,
int peer)
{
struct smc_sock *smc;
if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
(sock->sk->sk_state != SMC_APPCLOSEWAIT1))
return -ENOTCONN;
smc = smc_sk(sock->sk);
return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
}
static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
{
struct sock *sk = sock->sk;
struct smc_sock *smc;
int rc = -EPIPE;
smc = smc_sk(sk);
lock_sock(sk);
if ((sk->sk_state != SMC_ACTIVE) &&
(sk->sk_state != SMC_APPCLOSEWAIT1) &&
(sk->sk_state != SMC_INIT))
goto out;
if (msg->msg_flags & MSG_FASTOPEN) {
if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
smc_switch_to_fallback(smc);
smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
} else {
rc = -EINVAL;
goto out;
}
}
if (smc->use_fallback)
rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
else
rc = smc_tx_sendmsg(smc, msg, len);
out:
release_sock(sk);
return rc;
}
static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
int flags)
{
struct sock *sk = sock->sk;
struct smc_sock *smc;
int rc = -ENOTCONN;
smc = smc_sk(sk);
lock_sock(sk);
if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
/* socket was connected before, no more data to read */
rc = 0;
goto out;
}
if ((sk->sk_state == SMC_INIT) ||
(sk->sk_state == SMC_LISTEN) ||
(sk->sk_state == SMC_CLOSED))
goto out;
if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
rc = 0;
goto out;
}
if (smc->use_fallback) {
rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
} else {
msg->msg_namelen = 0;
rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
}
out:
release_sock(sk);
return rc;
}
static __poll_t smc_accept_poll(struct sock *parent)
{
struct smc_sock *isk = smc_sk(parent);
__poll_t mask = 0;
spin_lock(&isk->accept_q_lock);
if (!list_empty(&isk->accept_q))
mask = EPOLLIN | EPOLLRDNORM;
spin_unlock(&isk->accept_q_lock);
return mask;
}
static __poll_t smc_poll(struct file *file, struct socket *sock,
poll_table *wait)
{
struct sock *sk = sock->sk;
struct smc_sock *smc;
__poll_t mask = 0;
if (!sk)
return EPOLLNVAL;
smc = smc_sk(sock->sk);
if (smc->use_fallback) {
/* delegate to CLC child sock */
mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
sk->sk_err = smc->clcsock->sk->sk_err;
} else {
if (sk->sk_state != SMC_CLOSED)
sock_poll_wait(file, sock, wait);
if (sk->sk_err)
mask |= EPOLLERR;
if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
(sk->sk_state == SMC_CLOSED))
mask |= EPOLLHUP;
if (sk->sk_state == SMC_LISTEN) {
/* woken up by sk_data_ready in smc_listen_work() */
mask |= smc_accept_poll(sk);
} else if (smc->use_fallback) { /* as result of connect_work()*/
mask |= smc->clcsock->ops->poll(file, smc->clcsock,
wait);
sk->sk_err = smc->clcsock->sk->sk_err;
} else {
if ((sk->sk_state != SMC_INIT &&
atomic_read(&smc->conn.sndbuf_space)) ||
sk->sk_shutdown & SEND_SHUTDOWN) {
mask |= EPOLLOUT | EPOLLWRNORM;
} else {
sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
}
if (atomic_read(&smc->conn.bytes_to_rcv))
mask |= EPOLLIN | EPOLLRDNORM;
if (sk->sk_shutdown & RCV_SHUTDOWN)
mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
if (sk->sk_state == SMC_APPCLOSEWAIT1)
mask |= EPOLLIN;
if (smc->conn.urg_state == SMC_URG_VALID)
mask |= EPOLLPRI;
}
}
return mask;
}
static int smc_shutdown(struct socket *sock, int how)
{
struct sock *sk = sock->sk;
struct smc_sock *smc;
int rc = -EINVAL;
int rc1 = 0;
smc = smc_sk(sk);
if ((how < SHUT_RD) || (how > SHUT_RDWR))
return rc;
lock_sock(sk);
rc = -ENOTCONN;
if ((sk->sk_state != SMC_ACTIVE) &&
(sk->sk_state != SMC_PEERCLOSEWAIT1) &&
(sk->sk_state != SMC_PEERCLOSEWAIT2) &&
(sk->sk_state != SMC_APPCLOSEWAIT1) &&
(sk->sk_state != SMC_APPCLOSEWAIT2) &&
(sk->sk_state != SMC_APPFINCLOSEWAIT))
goto out;
if (smc->use_fallback) {
rc = kernel_sock_shutdown(smc->clcsock, how);
sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
if (sk->sk_shutdown == SHUTDOWN_MASK)
sk->sk_state = SMC_CLOSED;
goto out;
}
switch (how) {
case SHUT_RDWR: /* shutdown in both directions */
rc = smc_close_active(smc);
break;
case SHUT_WR:
rc = smc_close_shutdown_write(smc);
break;
case SHUT_RD:
rc = 0;
/* nothing more to do because peer is not involved */
break;
}
if (smc->clcsock)
rc1 = kernel_sock_shutdown(smc->clcsock, how);
/* map sock_shutdown_cmd constants to sk_shutdown value range */
sk->sk_shutdown |= how + 1;
out:
release_sock(sk);
return rc ? rc : rc1;
}
static int smc_setsockopt(struct socket *sock, int level, int optname,
char __user *optval, unsigned int optlen)
{
struct sock *sk = sock->sk;
struct smc_sock *smc;
int val, rc;
smc = smc_sk(sk);
/* generic setsockopts reaching us here always apply to the
* CLC socket
*/
rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
optval, optlen);
if (smc->clcsock->sk->sk_err) {
sk->sk_err = smc->clcsock->sk->sk_err;
sk->sk_error_report(sk);
}
if (optlen < sizeof(int))
return -EINVAL;
if (get_user(val, (int __user *)optval))
return -EFAULT;
lock_sock(sk);
if (rc || smc->use_fallback)
goto out;
switch (optname) {
case TCP_ULP:
case TCP_FASTOPEN:
case TCP_FASTOPEN_CONNECT:
case TCP_FASTOPEN_KEY:
case TCP_FASTOPEN_NO_COOKIE:
/* option not supported by SMC */
if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
smc_switch_to_fallback(smc);
smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
} else {
rc = -EINVAL;
}
break;
case TCP_NODELAY:
if (sk->sk_state != SMC_INIT &&
sk->sk_state != SMC_LISTEN &&
sk->sk_state != SMC_CLOSED) {
if (val)
mod_delayed_work(system_wq, &smc->conn.tx_work,
0);
}
break;
case TCP_CORK:
if (sk->sk_state != SMC_INIT &&
sk->sk_state != SMC_LISTEN &&
sk->sk_state != SMC_CLOSED) {
if (!val)
mod_delayed_work(system_wq, &smc->conn.tx_work,
0);
}
break;
case TCP_DEFER_ACCEPT:
smc->sockopt_defer_accept = val;
break;
default:
break;
}
out:
release_sock(sk);
return rc;
}
static int smc_getsockopt(struct socket *sock, int level, int optname,
char __user *optval, int __user *optlen)
{
struct smc_sock *smc;
smc = smc_sk(sock->sk);
/* socket options apply to the CLC socket */
return smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
optval, optlen);
}
static int smc_ioctl(struct socket *sock, unsigned int cmd,
unsigned long arg)
{
union smc_host_cursor cons, urg;
struct smc_connection *conn;
struct smc_sock *smc;
int answ;
smc = smc_sk(sock->sk);
conn = &smc->conn;
lock_sock(&smc->sk);
if (smc->use_fallback) {
if (!smc->clcsock) {
release_sock(&smc->sk);
return -EBADF;
}
answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
release_sock(&smc->sk);
return answ;
}
switch (cmd) {
case SIOCINQ: /* same as FIONREAD */
if (smc->sk.sk_state == SMC_LISTEN) {
release_sock(&smc->sk);
return -EINVAL;
}
if (smc->sk.sk_state == SMC_INIT ||
smc->sk.sk_state == SMC_CLOSED)
answ = 0;
else
answ = atomic_read(&smc->conn.bytes_to_rcv);
break;
case SIOCOUTQ:
/* output queue size (not send + not acked) */
if (smc->sk.sk_state == SMC_LISTEN) {
release_sock(&smc->sk);
return -EINVAL;
}
if (smc->sk.sk_state == SMC_INIT ||
smc->sk.sk_state == SMC_CLOSED)
answ = 0;
else
answ = smc->conn.sndbuf_desc->len -
atomic_read(&smc->conn.sndbuf_space);
break;
case SIOCOUTQNSD:
/* output queue size (not send only) */
if (smc->sk.sk_state == SMC_LISTEN) {
release_sock(&smc->sk);
return -EINVAL;
}
if (smc->sk.sk_state == SMC_INIT ||
smc->sk.sk_state == SMC_CLOSED)
answ = 0;
else
answ = smc_tx_prepared_sends(&smc->conn);
break;
case SIOCATMARK:
if (smc->sk.sk_state == SMC_LISTEN) {
release_sock(&smc->sk);
return -EINVAL;
}
if (smc->sk.sk_state == SMC_INIT ||
smc->sk.sk_state == SMC_CLOSED) {
answ = 0;
} else {
smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
smc_curs_copy(&urg, &conn->urg_curs, conn);
answ = smc_curs_diff(conn->rmb_desc->len,
&cons, &urg) == 1;
}
break;
default:
release_sock(&smc->sk);
return -ENOIOCTLCMD;
}
release_sock(&smc->sk);
return put_user(answ, (int __user *)arg);
}
static ssize_t smc_sendpage(struct socket *sock, struct page *page,
int offset, size_t size, int flags)
{
struct sock *sk = sock->sk;
struct smc_sock *smc;
int rc = -EPIPE;
smc = smc_sk(sk);
lock_sock(sk);
if (sk->sk_state != SMC_ACTIVE) {
release_sock(sk);
goto out;
}
release_sock(sk);
if (smc->use_fallback)
rc = kernel_sendpage(smc->clcsock, page, offset,
size, flags);
else
rc = sock_no_sendpage(sock, page, offset, size, flags);
out:
return rc;
}
/* Map the affected portions of the rmbe into an spd, note the number of bytes
* to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
* updates till whenever a respective page has been fully processed.
* Note that subsequent recv() calls have to wait till all splice() processing
* completed.
*/
static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
struct pipe_inode_info *pipe, size_t len,
unsigned int flags)
{
struct sock *sk = sock->sk;
struct smc_sock *smc;
int rc = -ENOTCONN;
smc = smc_sk(sk);
lock_sock(sk);
if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
/* socket was connected before, no more data to read */
rc = 0;
goto out;
}
if (sk->sk_state == SMC_INIT ||
sk->sk_state == SMC_LISTEN ||
sk->sk_state == SMC_CLOSED)
goto out;
if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
rc = 0;
goto out;
}
if (smc->use_fallback) {
rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
pipe, len, flags);
} else {
if (*ppos) {
rc = -ESPIPE;
goto out;
}
if (flags & SPLICE_F_NONBLOCK)
flags = MSG_DONTWAIT;
else
flags = 0;
rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
}
out:
release_sock(sk);
return rc;
}
/* must look like tcp */
static const struct proto_ops smc_sock_ops = {
.family = PF_SMC,
.owner = THIS_MODULE,
.release = smc_release,
.bind = smc_bind,
.connect = smc_connect,
.socketpair = sock_no_socketpair,
.accept = smc_accept,
.getname = smc_getname,
.poll = smc_poll,
.ioctl = smc_ioctl,
.listen = smc_listen,
.shutdown = smc_shutdown,
.setsockopt = smc_setsockopt,
.getsockopt = smc_getsockopt,
.sendmsg = smc_sendmsg,
.recvmsg = smc_recvmsg,
.mmap = sock_no_mmap,
.sendpage = smc_sendpage,
.splice_read = smc_splice_read,
};
static int smc_create(struct net *net, struct socket *sock, int protocol,
int kern)
{
int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
struct smc_sock *smc;
struct sock *sk;
int rc;
rc = -ESOCKTNOSUPPORT;
if (sock->type != SOCK_STREAM)
goto out;
rc = -EPROTONOSUPPORT;
if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
goto out;
rc = -ENOBUFS;
sock->ops = &smc_sock_ops;
sk = smc_sock_alloc(net, sock, protocol);
if (!sk)
goto out;
/* create internal TCP socket for CLC handshake and fallback */
smc = smc_sk(sk);
smc->use_fallback = false; /* assume rdma capability first */
smc->fallback_rsn = 0;
rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
&smc->clcsock);
if (rc) {
sk_common_release(sk);
goto out;
}
smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE);
smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE);
out:
return rc;
}
static const struct net_proto_family smc_sock_family_ops = {
.family = PF_SMC,
.owner = THIS_MODULE,
.create = smc_create,
};
unsigned int smc_net_id;
static __net_init int smc_net_init(struct net *net)
{
return smc_pnet_net_init(net);
}
static void __net_exit smc_net_exit(struct net *net)
{
smc_pnet_net_exit(net);
}
static struct pernet_operations smc_net_ops = {
.init = smc_net_init,
.exit = smc_net_exit,
.id = &smc_net_id,
.size = sizeof(struct smc_net),
};
static int __init smc_init(void)
{
int rc;
rc = register_pernet_subsys(&smc_net_ops);
if (rc)
return rc;
rc = smc_pnet_init();
if (rc)
goto out_pernet_subsys;
rc = smc_core_init();
if (rc) {
pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
goto out_pnet;
}
rc = smc_llc_init();
if (rc) {
pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
goto out_core;
}
rc = smc_cdc_init();
if (rc) {
pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
goto out_core;
}
rc = proto_register(&smc_proto, 1);
if (rc) {
pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
goto out_core;
}
rc = proto_register(&smc_proto6, 1);
if (rc) {
pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
goto out_proto;
}
rc = sock_register(&smc_sock_family_ops);
if (rc) {
pr_err("%s: sock_register fails with %d\n", __func__, rc);
goto out_proto6;
}
INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
rc = smc_ib_register_client();
if (rc) {
pr_err("%s: ib_register fails with %d\n", __func__, rc);
goto out_sock;
}
static_branch_enable(&tcp_have_smc);
return 0;
out_sock:
sock_unregister(PF_SMC);
out_proto6:
proto_unregister(&smc_proto6);
out_proto:
proto_unregister(&smc_proto);
out_core:
smc_core_exit();
out_pnet:
smc_pnet_exit();
out_pernet_subsys:
unregister_pernet_subsys(&smc_net_ops);
return rc;
}
static void __exit smc_exit(void)
{
static_branch_disable(&tcp_have_smc);
sock_unregister(PF_SMC);
smc_core_exit();
smc_ib_unregister_client();
proto_unregister(&smc_proto6);
proto_unregister(&smc_proto);
smc_pnet_exit();
unregister_pernet_subsys(&smc_net_ops);
rcu_barrier();
}
module_init(smc_init);
module_exit(smc_exit);
MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
MODULE_DESCRIPTION("smc socket address family");
MODULE_LICENSE("GPL");
MODULE_ALIAS_NETPROTO(PF_SMC);