blob: 544bab42f925a1eb90ac537a1eee7398e92a7c9f [file] [log] [blame]
/*
* 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
* - partial support for non-blocking sockets only
* - support for urgent data 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 <net/sock.h>
#include <net/tcp.h>
#include <net/smc.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_pnet.h"
#include "smc_tx.h"
#include "smc_rx.h"
#include "smc_close.h"
static DEFINE_MUTEX(smc_create_lgr_pending); /* serialize link group
* creation
*/
struct smc_lgr_list smc_lgr_list = { /* established link groups */
.lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock),
.list = LIST_HEAD_INIT(smc_lgr_list.list),
};
static void smc_tcp_listen_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 int smc_release(struct socket *sock)
{
struct sock *sk = sock->sk;
struct smc_sock *smc;
int rc = 0;
if (!sk)
goto out;
smc = smc_sk(sk);
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);
if (!smc->use_fallback) {
rc = smc_close_active(smc);
sock_set_flag(sk, SOCK_DEAD);
sk->sk_shutdown |= SHUTDOWN_MASK;
}
if (smc->clcsock) {
sock_release(smc->clcsock);
smc->clcsock = NULL;
}
if (smc->use_fallback) {
sock_put(sk); /* passive closing */
sk->sk_state = SMC_CLOSED;
sk->sk_state_change(sk);
}
/* detach socket */
sock_orphan(sk);
sock->sk = NULL;
if (!smc->use_fallback && sk->sk_state == SMC_CLOSED)
smc_conn_free(&smc->conn);
release_sock(sk);
sk->sk_prot->unhash(sk);
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_LIST_HEAD(&smc->accept_q);
spin_lock_init(&smc->accept_q_lock);
sk->sk_prot->hash(sk);
sk_refcnt_debug_inc(sk);
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)
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))
/* 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 */
static int smc_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc)
{
/* 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;
}
return 0;
}
static int smc_clnt_conf_first_link(struct smc_sock *smc)
{
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);
return 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_INTERR;
smc_wr_remember_qp_attr(link);
if (smc_reg_rmb(link, smc->conn.rmb_desc))
return SMC_CLC_DECL_INTERR;
/* send CONFIRM LINK response over RoCE fabric */
rc = smc_llc_send_confirm_link(link,
link->smcibdev->mac[link->ibport - 1],
&link->smcibdev->gid[link->ibport - 1],
SMC_LLC_RESP);
if (rc < 0)
return SMC_CLC_DECL_TCL;
/* 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);
return 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->smcibdev->gid[link->ibport - 1],
SMC_LLC_RESP);
if (rc < 0)
return SMC_CLC_DECL_TCL;
link->state = SMC_LNK_ACTIVE;
return 0;
}
static void smc_conn_save_peer_info(struct smc_sock *smc,
struct smc_clc_msg_accept_confirm *clc)
{
smc->conn.peer_conn_idx = clc->conn_idx;
smc->conn.local_tx_ctrl.token = ntohl(clc->rmbe_alert_token);
smc->conn.peer_rmbe_size = smc_uncompress_bufsize(clc->rmbe_size);
atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
}
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;
}
/* setup for RDMA connection of client */
static int smc_connect_rdma(struct smc_sock *smc)
{
struct smc_clc_msg_accept_confirm aclc;
int local_contact = SMC_FIRST_CONTACT;
struct smc_ib_device *smcibdev;
struct smc_link *link;
u8 srv_first_contact;
int reason_code = 0;
int rc = 0;
u8 ibport;
sock_hold(&smc->sk); /* sock put in passive closing */
if (!tcp_sk(smc->clcsock->sk)->syn_smc) {
/* peer has not signalled SMC-capability */
smc->use_fallback = true;
goto out_connected;
}
/* IPSec connections opt out of SMC-R optimizations */
if (using_ipsec(smc)) {
reason_code = SMC_CLC_DECL_IPSEC;
goto decline_rdma;
}
/* 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, &smcibdev, &ibport);
if (!smcibdev) {
reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
goto decline_rdma;
}
/* do inband token exchange */
reason_code = smc_clc_send_proposal(smc, smcibdev, ibport);
if (reason_code < 0) {
rc = reason_code;
goto out_err;
}
if (reason_code > 0) /* configuration error */
goto decline_rdma;
/* receive SMC Accept CLC message */
reason_code = smc_clc_wait_msg(smc, &aclc, sizeof(aclc),
SMC_CLC_ACCEPT);
if (reason_code < 0) {
rc = reason_code;
goto out_err;
}
if (reason_code > 0)
goto decline_rdma;
srv_first_contact = aclc.hdr.flag;
mutex_lock(&smc_create_lgr_pending);
local_contact = smc_conn_create(smc, smcibdev, ibport, &aclc.lcl,
srv_first_contact);
if (local_contact < 0) {
rc = local_contact;
if (rc == -ENOMEM)
reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/
else if (rc == -ENOLINK)
reason_code = SMC_CLC_DECL_SYNCERR; /* synchr. error */
goto decline_rdma_unlock;
}
link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK];
smc_conn_save_peer_info(smc, &aclc);
/* create send buffer and rmb */
rc = smc_buf_create(smc);
if (rc) {
reason_code = SMC_CLC_DECL_MEM;
goto decline_rdma_unlock;
}
if (local_contact == SMC_FIRST_CONTACT)
smc_link_save_peer_info(link, &aclc);
rc = smc_rmb_rtoken_handling(&smc->conn, &aclc);
if (rc) {
reason_code = SMC_CLC_DECL_INTERR;
goto decline_rdma_unlock;
}
smc_close_init(smc);
smc_rx_init(smc);
if (local_contact == SMC_FIRST_CONTACT) {
rc = smc_ib_ready_link(link);
if (rc) {
reason_code = SMC_CLC_DECL_INTERR;
goto decline_rdma_unlock;
}
} else {
if (!smc->conn.rmb_desc->reused) {
if (smc_reg_rmb(link, smc->conn.rmb_desc)) {
reason_code = SMC_CLC_DECL_INTERR;
goto decline_rdma_unlock;
}
}
}
smc_rmb_sync_sg_for_device(&smc->conn);
rc = smc_clc_send_confirm(smc);
if (rc)
goto out_err_unlock;
if (local_contact == SMC_FIRST_CONTACT) {
/* QP confirmation over RoCE fabric */
reason_code = smc_clnt_conf_first_link(smc);
if (reason_code < 0) {
rc = reason_code;
goto out_err_unlock;
}
if (reason_code > 0)
goto decline_rdma_unlock;
}
mutex_unlock(&smc_create_lgr_pending);
smc_tx_init(smc);
out_connected:
smc_copy_sock_settings_to_clc(smc);
if (smc->sk.sk_state == SMC_INIT)
smc->sk.sk_state = SMC_ACTIVE;
return rc ? rc : local_contact;
decline_rdma_unlock:
if (local_contact == SMC_FIRST_CONTACT)
smc_lgr_forget(smc->conn.lgr);
mutex_unlock(&smc_create_lgr_pending);
smc_conn_free(&smc->conn);
decline_rdma:
/* RDMA setup failed, switch back to TCP */
smc->use_fallback = true;
if (reason_code && (reason_code != SMC_CLC_DECL_REPLY)) {
rc = smc_clc_send_decline(smc, reason_code);
if (rc < 0)
goto out_err;
}
goto out_connected;
out_err_unlock:
if (local_contact == SMC_FIRST_CONTACT)
smc_lgr_forget(smc->conn.lgr);
mutex_unlock(&smc_create_lgr_pending);
smc_conn_free(&smc->conn);
out_err:
if (smc->sk.sk_state == SMC_INIT)
sock_put(&smc->sk); /* passive closing */
return rc;
}
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;
rc = kernel_connect(smc->clcsock, addr, alen, flags);
if (rc)
goto out;
/* setup RDMA connection */
rc = smc_connect_rdma(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;
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);
rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0);
lock_sock(lsk);
if (rc < 0)
lsk->sk_err = -rc;
if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
if (new_clcsock)
sock_release(new_clcsock);
new_sk->sk_state = SMC_CLOSED;
sock_set_flag(new_sk, SOCK_DEAD);
new_sk->sk_prot->unhash(new_sk);
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) {
if (isk->clcsock) {
sock_release(isk->clcsock);
isk->clcsock = NULL;
}
new_sk->sk_prot->unhash(new_sk);
sock_put(new_sk); /* final */
continue;
}
if (new_sock)
sock_graft(new_sk, new_sock);
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);
lock_sock(sk);
if (!sk->sk_lingertime)
/* wait for peer closing */
sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
if (!smc->use_fallback) {
smc_close_active(smc);
sock_set_flag(sk, SOCK_DEAD);
sk->sk_shutdown |= SHUTDOWN_MASK;
}
if (smc->clcsock) {
struct socket *tcp;
tcp = smc->clcsock;
smc->clcsock = NULL;
sock_release(tcp);
}
if (smc->use_fallback) {
sock_put(sk); /* passive closing */
sk->sk_state = SMC_CLOSED;
} else {
if (sk->sk_state == SMC_CLOSED)
smc_conn_free(&smc->conn);
}
release_sock(sk);
sk->sk_prot->unhash(sk);
sock_put(sk); /* final sock_put */
}
static int smc_serv_conf_first_link(struct smc_sock *smc)
{
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))
return SMC_CLC_DECL_INTERR;
/* send CONFIRM LINK request to client over the RoCE fabric */
rc = smc_llc_send_confirm_link(link,
link->smcibdev->mac[link->ibport - 1],
&link->smcibdev->gid[link->ibport - 1],
SMC_LLC_REQ);
if (rc < 0)
return SMC_CLC_DECL_TCL;
/* 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);
return 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->smcibdev->gid[link->ibport - 1],
SMC_LLC_REQ);
if (rc < 0)
return SMC_CLC_DECL_TCL;
/* 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);
return rc;
}
link->state = SMC_LNK_ACTIVE;
return 0;
}
/* 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 smc_clc_msg_proposal_prefix *pclc_prfx;
struct socket *newclcsock = new_smc->clcsock;
struct smc_sock *lsmc = new_smc->listen_smc;
struct smc_clc_msg_accept_confirm cclc;
int local_contact = SMC_REUSE_CONTACT;
struct sock *newsmcsk = &new_smc->sk;
struct smc_clc_msg_proposal *pclc;
struct smc_ib_device *smcibdev;
u8 buf[SMC_CLC_MAX_LEN];
struct smc_link *link;
int reason_code = 0;
int rc = 0;
u8 ibport;
/* check if peer is smc capable */
if (!tcp_sk(newclcsock->sk)->syn_smc) {
new_smc->use_fallback = true;
goto out_connected;
}
/* do inband token exchange -
*wait for and receive SMC Proposal CLC message
*/
reason_code = smc_clc_wait_msg(new_smc, &buf, sizeof(buf),
SMC_CLC_PROPOSAL);
if (reason_code < 0)
goto out_err;
if (reason_code > 0)
goto decline_rdma;
/* IPSec connections opt out of SMC-R optimizations */
if (using_ipsec(new_smc)) {
reason_code = SMC_CLC_DECL_IPSEC;
goto decline_rdma;
}
/* 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(newclcsock->sk, &smcibdev, &ibport);
if (!smcibdev) {
reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
goto decline_rdma;
}
pclc = (struct smc_clc_msg_proposal *)&buf;
pclc_prfx = smc_clc_proposal_get_prefix(pclc);
rc = smc_clc_prfx_match(newclcsock, pclc_prfx);
if (rc) {
reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
goto decline_rdma;
}
/* allocate connection / link group */
mutex_lock(&smc_create_lgr_pending);
local_contact = smc_conn_create(new_smc, smcibdev, ibport, &pclc->lcl,
0);
if (local_contact < 0) {
rc = local_contact;
if (rc == -ENOMEM)
reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/
goto decline_rdma_unlock;
}
link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
/* create send buffer and rmb */
rc = smc_buf_create(new_smc);
if (rc) {
reason_code = SMC_CLC_DECL_MEM;
goto decline_rdma_unlock;
}
smc_close_init(new_smc);
smc_rx_init(new_smc);
if (local_contact != SMC_FIRST_CONTACT) {
if (!new_smc->conn.rmb_desc->reused) {
if (smc_reg_rmb(link, new_smc->conn.rmb_desc)) {
reason_code = SMC_CLC_DECL_INTERR;
goto decline_rdma_unlock;
}
}
}
smc_rmb_sync_sg_for_device(&new_smc->conn);
rc = smc_clc_send_accept(new_smc, local_contact);
if (rc)
goto out_err_unlock;
/* receive SMC Confirm CLC message */
reason_code = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc),
SMC_CLC_CONFIRM);
if (reason_code < 0)
goto out_err_unlock;
if (reason_code > 0)
goto decline_rdma_unlock;
smc_conn_save_peer_info(new_smc, &cclc);
if (local_contact == SMC_FIRST_CONTACT)
smc_link_save_peer_info(link, &cclc);
rc = smc_rmb_rtoken_handling(&new_smc->conn, &cclc);
if (rc) {
reason_code = SMC_CLC_DECL_INTERR;
goto decline_rdma_unlock;
}
if (local_contact == SMC_FIRST_CONTACT) {
rc = smc_ib_ready_link(link);
if (rc) {
reason_code = SMC_CLC_DECL_INTERR;
goto decline_rdma_unlock;
}
/* QP confirmation over RoCE fabric */
reason_code = smc_serv_conf_first_link(new_smc);
if (reason_code < 0)
/* peer is not aware of a problem */
goto out_err_unlock;
if (reason_code > 0)
goto decline_rdma_unlock;
}
smc_tx_init(new_smc);
mutex_unlock(&smc_create_lgr_pending);
out_connected:
sk_refcnt_debug_inc(newsmcsk);
if (newsmcsk->sk_state == SMC_INIT)
newsmcsk->sk_state = SMC_ACTIVE;
enqueue:
lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
if (lsmc->sk.sk_state == SMC_LISTEN) {
smc_accept_enqueue(&lsmc->sk, newsmcsk);
} else { /* no longer listening */
smc_close_non_accepted(newsmcsk);
}
release_sock(&lsmc->sk);
/* Wake up accept */
lsmc->sk.sk_data_ready(&lsmc->sk);
sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
return;
decline_rdma_unlock:
if (local_contact == SMC_FIRST_CONTACT)
smc_lgr_forget(new_smc->conn.lgr);
mutex_unlock(&smc_create_lgr_pending);
decline_rdma:
/* RDMA setup failed, switch back to TCP */
smc_conn_free(&new_smc->conn);
new_smc->use_fallback = true;
if (reason_code && (reason_code != SMC_CLC_DECL_REPLY)) {
if (smc_clc_send_decline(new_smc, reason_code) < 0)
goto out_err;
}
goto out_connected;
out_err_unlock:
if (local_contact == SMC_FIRST_CONTACT)
smc_lgr_forget(new_smc->conn.lgr);
mutex_unlock(&smc_create_lgr_pending);
out_err:
if (newsmcsk->sk_state == SMC_INIT)
sock_put(&new_smc->sk); /* passive closing */
newsmcsk->sk_state = SMC_CLOSED;
smc_conn_free(&new_smc->conn);
goto enqueue; /* queue new sock with sk_err set */
}
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 = false; /* assume rdma capability first*/
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);
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))
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);
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;
INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
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;
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);
out:
release_sock(sk);
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 (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_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
rc = smc_rx_recvmsg(smc, msg, 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;
__poll_t mask = 0;
struct smc_sock *smc;
int rc;
if (!sk)
return EPOLLNVAL;
smc = smc_sk(sock->sk);
sock_hold(sk);
lock_sock(sk);
if ((sk->sk_state == SMC_INIT) || smc->use_fallback) {
/* delegate to CLC child sock */
release_sock(sk);
mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
lock_sock(sk);
sk->sk_err = smc->clcsock->sk->sk_err;
if (sk->sk_err) {
mask |= EPOLLERR;
} else {
/* if non-blocking connect finished ... */
if (sk->sk_state == SMC_INIT &&
mask & EPOLLOUT &&
smc->clcsock->sk->sk_state != TCP_CLOSE) {
rc = smc_connect_rdma(smc);
if (rc < 0)
mask |= EPOLLERR;
/* success cases including fallback */
mask |= EPOLLOUT | EPOLLWRNORM;
}
}
} else {
if (sk->sk_state != SMC_CLOSED) {
release_sock(sk);
sock_poll_wait(file, sk_sleep(sk), wait);
lock_sock(sk);
}
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 (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;
}
}
release_sock(sk);
sock_put(sk);
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_LISTEN) &&
(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;
smc = smc_sk(sk);
/* generic setsockopts reaching us here always apply to the
* CLC socket
*/
return smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
optval, optlen);
}
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)
{
struct smc_sock *smc;
smc = smc_sk(sock->sk);
if (smc->use_fallback)
return smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
else
return sock_no_ioctl(sock, cmd, 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;
}
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_ACTIVE) && (sk->sk_state != SMC_CLOSED))
goto out;
if (smc->use_fallback) {
rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
pipe, len, flags);
} else {
rc = -EOPNOTSUPP;
}
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 */
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,
};
static int __init smc_init(void)
{
int rc;
rc = smc_pnet_init();
if (rc)
return rc;
rc = smc_llc_init();
if (rc) {
pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
goto out_pnet;
}
rc = smc_cdc_init();
if (rc) {
pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
goto out_pnet;
}
rc = proto_register(&smc_proto, 1);
if (rc) {
pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
goto out_pnet;
}
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_pnet:
smc_pnet_exit();
return rc;
}
static void __exit smc_exit(void)
{
struct smc_link_group *lgr, *lg;
LIST_HEAD(lgr_freeing_list);
spin_lock_bh(&smc_lgr_list.lock);
if (!list_empty(&smc_lgr_list.list))
list_splice_init(&smc_lgr_list.list, &lgr_freeing_list);
spin_unlock_bh(&smc_lgr_list.lock);
list_for_each_entry_safe(lgr, lg, &lgr_freeing_list, list) {
list_del_init(&lgr->list);
cancel_delayed_work_sync(&lgr->free_work);
smc_lgr_free(lgr); /* free link group */
}
static_branch_disable(&tcp_have_smc);
smc_ib_unregister_client();
sock_unregister(PF_SMC);
proto_unregister(&smc_proto6);
proto_unregister(&smc_proto);
smc_pnet_exit();
}
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);