linux/net/smc/af_smc.c
Ursula Braun a046d57da1 smc: CLC handshake (incl. preparation steps)
* CLC (Connection Layer Control) handshake

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-09 16:07:39 -05:00

1040 lines
24 KiB
C

/*
* 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:
* - non-blocking connect postponed
* - IPv6 support postponed
* - support for alternate links postponed
* - partial support for non-blocking sockets only
* - support for urgent data postponed
*
* Copyright IBM Corp. 2016
*
* 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/inetdevice.h>
#include <linux/workqueue.h>
#include <net/sock.h>
#include <net/tcp.h>
#include "smc.h"
#include "smc_clc.h"
#include "smc_ib.h"
#include "smc_pnet.h"
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 proto smc_proto = {
.name = "SMC",
.owner = THIS_MODULE,
.keepalive = smc_set_keepalive,
.obj_size = sizeof(struct smc_sock),
.slab_flags = SLAB_DESTROY_BY_RCU,
};
static int smc_release(struct socket *sock)
{
struct sock *sk = sock->sk;
struct smc_sock *smc;
if (!sk)
goto out;
smc = smc_sk(sk);
lock_sock(sk);
sk->sk_state = SMC_CLOSED;
if (smc->clcsock) {
sock_release(smc->clcsock);
smc->clcsock = NULL;
}
/* detach socket */
sock_orphan(sk);
sock->sk = NULL;
release_sock(sk);
sock_put(sk);
out:
return 0;
}
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)
{
struct smc_sock *smc;
struct sock *sk;
sk = sk_alloc(net, PF_SMC, GFP_KERNEL, &smc_proto, 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 = SMCPROTO_SMC;
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_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;
/* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
if ((addr->sin_family != AF_INET) &&
((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);
}
/* determine subnet and mask of internal TCP socket */
int smc_netinfo_by_tcpsk(struct socket *clcsock,
__be32 *subnet, u8 *prefix_len)
{
struct dst_entry *dst = sk_dst_get(clcsock->sk);
struct sockaddr_in addr;
int rc = -ENOENT;
int len;
if (!dst) {
rc = -ENOTCONN;
goto out;
}
if (!dst->dev) {
rc = -ENODEV;
goto out_rel;
}
/* get address to which the internal TCP socket is bound */
kernel_getsockname(clcsock, (struct sockaddr *)&addr, &len);
/* analyze IPv4 specific data of net_device belonging to TCP socket */
for_ifa(dst->dev->ip_ptr) {
if (ifa->ifa_address != addr.sin_addr.s_addr)
continue;
*prefix_len = inet_mask_len(ifa->ifa_mask);
*subnet = ifa->ifa_address & ifa->ifa_mask;
rc = 0;
break;
} endfor_ifa(dst->dev->ip_ptr);
out_rel:
dst_release(dst);
out:
return rc;
}
/* setup for RDMA connection of client */
static int smc_connect_rdma(struct smc_sock *smc)
{
struct smc_clc_msg_accept_confirm aclc;
struct smc_ib_device *smcibdev;
int reason_code = 0;
int rc = 0;
u8 ibport;
/* 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;
/* tbd in follow-on patch: more steps to setup RDMA communcication,
* create connection, link group, link
*/
/* tbd in follow-on patch: more steps to setup RDMA communcication,
* create rmbs, map rmbs, rtoken_handling, modify_qp
*/
rc = smc_clc_send_confirm(smc);
if (rc)
goto out_err;
/* tbd in follow-on patch: llc_confirm */
out_connected:
smc_copy_sock_settings_to_clc(smc);
smc->sk.sk_state = SMC_ACTIVE;
return rc;
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, 0);
if (rc < sizeof(struct smc_clc_msg_decline))
goto out_err;
}
goto out_connected;
out_err:
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)
goto out_err;
smc->addr = addr; /* needed for nonblocking connect */
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);
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 sock *sk = &lsmc->sk;
struct socket *new_clcsock;
struct sock *new_sk;
int rc;
release_sock(&lsmc->sk);
new_sk = smc_sock_alloc(sock_net(sk), NULL);
if (!new_sk) {
rc = -ENOMEM;
lsmc->sk.sk_err = ENOMEM;
*new_smc = NULL;
lock_sock(&lsmc->sk);
goto out;
}
*new_smc = smc_sk(new_sk);
rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0);
lock_sock(&lsmc->sk);
if (rc < 0) {
lsmc->sk.sk_err = -rc;
new_sk->sk_state = SMC_CLOSED;
sock_set_flag(new_sk, SOCK_DEAD);
sock_put(new_sk);
*new_smc = NULL;
goto out;
}
if (lsmc->sk.sk_state == SMC_CLOSED) {
if (new_clcsock)
sock_release(new_clcsock);
new_sk->sk_state = SMC_CLOSED;
sock_set_flag(new_sk, SOCK_DEAD);
sock_put(new_sk);
*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);
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);
}
/* remove a sock from the accept queue to bind it to a new socket created
* for a socket accept call from user space
*/
static 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) {
/* tbd in follow-on patch: close this sock */
continue;
}
if (new_sock)
sock_graft(new_sk, new_sock);
return new_sk;
}
return NULL;
}
/* clean up for a created but never accepted sock */
static void smc_close_non_accepted(struct sock *sk)
{
struct smc_sock *smc = smc_sk(sk);
sock_hold(sk);
if (smc->clcsock) {
struct socket *tcp;
tcp = smc->clcsock;
smc->clcsock = NULL;
sock_release(tcp);
}
/* more closing stuff to be added with socket closing patch */
sock_put(sk);
}
/* 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_sock *lsmc = new_smc->listen_smc;
struct smc_clc_msg_accept_confirm cclc;
struct sock *newsmcsk = &new_smc->sk;
struct smc_clc_msg_proposal pclc;
struct smc_ib_device *smcibdev;
struct sockaddr_in peeraddr;
int reason_code = 0;
int rc = 0, len;
__be32 subnet;
u8 prefix_len;
u8 ibport;
/* do inband token exchange -
*wait for and receive SMC Proposal CLC message
*/
reason_code = smc_clc_wait_msg(new_smc, &pclc, sizeof(pclc),
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;
}
/* determine subnet and mask from internal TCP socket */
rc = smc_netinfo_by_tcpsk(newclcsock, &subnet, &prefix_len);
if (rc) {
reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
goto decline_rdma;
}
if ((pclc.outgoing_subnet != subnet) ||
(pclc.prefix_len != prefix_len)) {
reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
goto decline_rdma;
}
/* get address of the peer connected to the internal TCP socket */
kernel_getpeername(newclcsock, (struct sockaddr *)&peeraddr, &len);
/* tbd in follow-on patch: more steps to setup RDMA communcication,
* create connection, link_group, link
*/
/* tbd in follow-on patch: more steps to setup RDMA communcication,
* create rmbs, map rmbs
*/
rc = smc_clc_send_accept(new_smc);
if (rc)
goto out_err;
/* 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;
if (reason_code > 0)
goto decline_rdma;
/* tbd in follow-on patch: more steps to setup RDMA communcication,
* rtoken_handling, modify_qp
*/
out_connected:
sk_refcnt_debug_inc(newsmcsk);
newsmcsk->sk_state = SMC_ACTIVE;
enqueue:
lock_sock(&lsmc->sk);
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:
/* RDMA setup failed, switch back to TCP */
new_smc->use_fallback = true;
if (reason_code && (reason_code != SMC_CLC_DECL_REPLY)) {
rc = smc_clc_send_decline(new_smc, reason_code, 0);
if (rc < sizeof(struct smc_clc_msg_decline))
goto out_err;
}
goto out_connected;
out_err:
newsmcsk->sk_state = SMC_CLOSED;
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 smc_sock *new_smc;
int rc = 0;
lock_sock(&lsmc->sk);
while (lsmc->sk.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(&lsmc->sk); /* sock_put in smc_listen_work */
INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
smc_copy_sock_settings_to_smc(new_smc);
schedule_work(&new_smc->smc_listen_work);
}
out:
release_sock(&lsmc->sk);
lsmc->sk.sk_data_ready(&lsmc->sk); /* no more listening, wake accept */
}
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);
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);
schedule_work(&smc->tcp_listen_work);
out:
release_sock(sk);
return rc;
}
static int smc_accept(struct socket *sock, struct socket *new_sock,
int flags)
{
struct sock *sk = sock->sk, *nsk;
DECLARE_WAITQUEUE(wait, current);
struct smc_sock *lsmc;
long timeo;
int rc = 0;
lsmc = smc_sk(sk);
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);
return rc;
}
static int smc_getname(struct socket *sock, struct sockaddr *addr,
int *len, int peer)
{
struct smc_sock *smc;
if (peer && (sock->sk->sk_state != SMC_ACTIVE))
return -ENOTCONN;
smc = smc_sk(sock->sk);
return smc->clcsock->ops->getname(smc->clcsock, addr, len, 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)
goto out;
if (smc->use_fallback)
rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
else
rc = sock_no_sendmsg(sock, 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_ACTIVE) && (sk->sk_state != SMC_CLOSED))
goto out;
if (smc->use_fallback)
rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
else
rc = sock_no_recvmsg(sock, msg, len, flags);
out:
release_sock(sk);
return rc;
}
static unsigned int smc_accept_poll(struct sock *parent)
{
struct smc_sock *isk;
struct sock *sk;
lock_sock(parent);
list_for_each_entry(isk, &smc_sk(parent)->accept_q, accept_q) {
sk = (struct sock *)isk;
if (sk->sk_state == SMC_ACTIVE) {
release_sock(parent);
return POLLIN | POLLRDNORM;
}
}
release_sock(parent);
return 0;
}
static unsigned int smc_poll(struct file *file, struct socket *sock,
poll_table *wait)
{
struct sock *sk = sock->sk;
unsigned int mask = 0;
struct smc_sock *smc;
int rc;
smc = smc_sk(sock->sk);
if ((sk->sk_state == SMC_INIT) || smc->use_fallback) {
/* delegate to CLC child sock */
mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
/* if non-blocking connect finished ... */
lock_sock(sk);
if ((sk->sk_state == SMC_INIT) && (mask & POLLOUT)) {
sk->sk_err = smc->clcsock->sk->sk_err;
if (sk->sk_err) {
mask |= POLLERR;
} else {
rc = smc_connect_rdma(smc);
if (rc < 0)
mask |= POLLERR;
else
/* success cases including fallback */
mask |= POLLOUT | POLLWRNORM;
}
}
release_sock(sk);
} else {
sock_poll_wait(file, sk_sleep(sk), wait);
if (sk->sk_state == SMC_LISTEN)
/* woken up by sk_data_ready in smc_listen_work() */
mask |= smc_accept_poll(sk);
if (sk->sk_err)
mask |= POLLERR;
/* for now - to be enhanced in follow-on patch */
}
return mask;
}
static int smc_shutdown(struct socket *sock, int how)
{
struct sock *sk = sock->sk;
struct smc_sock *smc;
int rc = -EINVAL;
smc = smc_sk(sk);
if ((how < SHUT_RD) || (how > SHUT_RDWR))
goto out_err;
lock_sock(sk);
rc = -ENOTCONN;
if (sk->sk_state == SMC_CLOSED)
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;
} else {
rc = sock_no_shutdown(sock, how);
}
out:
release_sock(sk);
out_err:
return rc;
}
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)
goto out;
if (smc->use_fallback)
rc = kernel_sendpage(smc->clcsock, page, offset,
size, flags);
else
rc = sock_no_sendpage(sock, page, offset, size, flags);
out:
release_sock(sk);
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)
{
struct smc_sock *smc;
struct sock *sk;
int rc;
rc = -ESOCKTNOSUPPORT;
if (sock->type != SOCK_STREAM)
goto out;
rc = -EPROTONOSUPPORT;
if ((protocol != IPPROTO_IP) && (protocol != IPPROTO_TCP))
goto out;
rc = -ENOBUFS;
sock->ops = &smc_sock_ops;
sk = smc_sock_alloc(net, sock);
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, PF_INET, SOCK_STREAM,
IPPROTO_TCP, &smc->clcsock);
if (rc)
sk_common_release(sk);
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 = proto_register(&smc_proto, 1);
if (rc) {
pr_err("%s: proto_register fails with %d\n", __func__, rc);
goto out_pnet;
}
rc = sock_register(&smc_sock_family_ops);
if (rc) {
pr_err("%s: sock_register fails with %d\n", __func__, rc);
goto out_proto;
}
rc = smc_ib_register_client();
if (rc) {
pr_err("%s: ib_register fails with %d\n", __func__, rc);
goto out_sock;
}
return 0;
out_sock:
sock_unregister(PF_SMC);
out_proto:
proto_unregister(&smc_proto);
out_pnet:
smc_pnet_exit();
return rc;
}
static void __exit smc_exit(void)
{
smc_ib_unregister_client();
sock_unregister(PF_SMC);
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);