swh:1:snp:32555a3fd8878f019c2ebd6c964bc1edcaeff337
Tip revision: b04e217704b7f879c6b91222b066983a44a7a09f authored by Linus Torvalds on 27 May 2018, 20:01:47 UTC
Linux 4.17-rc7
Linux 4.17-rc7
Tip revision: b04e217
smc_clc.c
// SPDX-License-Identifier: GPL-2.0
/*
* Shared Memory Communications over RDMA (SMC-R) and RoCE
*
* CLC (connection layer control) handshake over initial TCP socket to
* prepare for RDMA traffic
*
* Copyright IBM Corp. 2016, 2018
*
* Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
*/
#include <linux/in.h>
#include <linux/inetdevice.h>
#include <linux/if_ether.h>
#include <linux/sched/signal.h>
#include <net/addrconf.h>
#include <net/sock.h>
#include <net/tcp.h>
#include "smc.h"
#include "smc_core.h"
#include "smc_clc.h"
#include "smc_ib.h"
/* eye catcher "SMCR" EBCDIC for CLC messages */
static const char SMC_EYECATCHER[4] = {'\xe2', '\xd4', '\xc3', '\xd9'};
/* check if received message has a correct header length and contains valid
* heading and trailing eyecatchers
*/
static bool smc_clc_msg_hdr_valid(struct smc_clc_msg_hdr *clcm)
{
struct smc_clc_msg_proposal_prefix *pclc_prfx;
struct smc_clc_msg_accept_confirm *clc;
struct smc_clc_msg_proposal *pclc;
struct smc_clc_msg_decline *dclc;
struct smc_clc_msg_trail *trl;
if (memcmp(clcm->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)))
return false;
switch (clcm->type) {
case SMC_CLC_PROPOSAL:
pclc = (struct smc_clc_msg_proposal *)clcm;
pclc_prfx = smc_clc_proposal_get_prefix(pclc);
if (ntohs(pclc->hdr.length) !=
sizeof(*pclc) + ntohs(pclc->iparea_offset) +
sizeof(*pclc_prfx) +
pclc_prfx->ipv6_prefixes_cnt *
sizeof(struct smc_clc_ipv6_prefix) +
sizeof(*trl))
return false;
trl = (struct smc_clc_msg_trail *)
((u8 *)pclc + ntohs(pclc->hdr.length) - sizeof(*trl));
break;
case SMC_CLC_ACCEPT:
case SMC_CLC_CONFIRM:
clc = (struct smc_clc_msg_accept_confirm *)clcm;
if (ntohs(clc->hdr.length) != sizeof(*clc))
return false;
trl = &clc->trl;
break;
case SMC_CLC_DECLINE:
dclc = (struct smc_clc_msg_decline *)clcm;
if (ntohs(dclc->hdr.length) != sizeof(*dclc))
return false;
trl = &dclc->trl;
break;
default:
return false;
}
if (memcmp(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)))
return false;
return true;
}
/* find ipv4 addr on device and get the prefix len, fill CLC proposal msg */
static int smc_clc_prfx_set4_rcu(struct dst_entry *dst, __be32 ipv4,
struct smc_clc_msg_proposal_prefix *prop)
{
struct in_device *in_dev = __in_dev_get_rcu(dst->dev);
if (!in_dev)
return -ENODEV;
for_ifa(in_dev) {
if (!inet_ifa_match(ipv4, ifa))
continue;
prop->prefix_len = inet_mask_len(ifa->ifa_mask);
prop->outgoing_subnet = ifa->ifa_address & ifa->ifa_mask;
/* prop->ipv6_prefixes_cnt = 0; already done by memset before */
return 0;
} endfor_ifa(in_dev);
return -ENOENT;
}
/* fill CLC proposal msg with ipv6 prefixes from device */
static int smc_clc_prfx_set6_rcu(struct dst_entry *dst,
struct smc_clc_msg_proposal_prefix *prop,
struct smc_clc_ipv6_prefix *ipv6_prfx)
{
#if IS_ENABLED(CONFIG_IPV6)
struct inet6_dev *in6_dev = __in6_dev_get(dst->dev);
struct inet6_ifaddr *ifa;
int cnt = 0;
if (!in6_dev)
return -ENODEV;
/* use a maximum of 8 IPv6 prefixes from device */
list_for_each_entry(ifa, &in6_dev->addr_list, if_list) {
if (ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)
continue;
ipv6_addr_prefix(&ipv6_prfx[cnt].prefix,
&ifa->addr, ifa->prefix_len);
ipv6_prfx[cnt].prefix_len = ifa->prefix_len;
cnt++;
if (cnt == SMC_CLC_MAX_V6_PREFIX)
break;
}
prop->ipv6_prefixes_cnt = cnt;
if (cnt)
return 0;
#endif
return -ENOENT;
}
/* retrieve and set prefixes in CLC proposal msg */
static int smc_clc_prfx_set(struct socket *clcsock,
struct smc_clc_msg_proposal_prefix *prop,
struct smc_clc_ipv6_prefix *ipv6_prfx)
{
struct dst_entry *dst = sk_dst_get(clcsock->sk);
struct sockaddr_storage addrs;
struct sockaddr_in6 *addr6;
struct sockaddr_in *addr;
int rc = -ENOENT;
memset(prop, 0, sizeof(*prop));
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 *)&addrs);
/* analyze IP specific data of net_device belonging to TCP socket */
addr6 = (struct sockaddr_in6 *)&addrs;
rcu_read_lock();
if (addrs.ss_family == PF_INET) {
/* IPv4 */
addr = (struct sockaddr_in *)&addrs;
rc = smc_clc_prfx_set4_rcu(dst, addr->sin_addr.s_addr, prop);
} else if (ipv6_addr_v4mapped(&addr6->sin6_addr)) {
/* mapped IPv4 address - peer is IPv4 only */
rc = smc_clc_prfx_set4_rcu(dst, addr6->sin6_addr.s6_addr32[3],
prop);
} else {
/* IPv6 */
rc = smc_clc_prfx_set6_rcu(dst, prop, ipv6_prfx);
}
rcu_read_unlock();
out_rel:
dst_release(dst);
out:
return rc;
}
/* match ipv4 addrs of dev against addr in CLC proposal */
static int smc_clc_prfx_match4_rcu(struct net_device *dev,
struct smc_clc_msg_proposal_prefix *prop)
{
struct in_device *in_dev = __in_dev_get_rcu(dev);
if (!in_dev)
return -ENODEV;
for_ifa(in_dev) {
if (prop->prefix_len == inet_mask_len(ifa->ifa_mask) &&
inet_ifa_match(prop->outgoing_subnet, ifa))
return 0;
} endfor_ifa(in_dev);
return -ENOENT;
}
/* match ipv6 addrs of dev against addrs in CLC proposal */
static int smc_clc_prfx_match6_rcu(struct net_device *dev,
struct smc_clc_msg_proposal_prefix *prop)
{
#if IS_ENABLED(CONFIG_IPV6)
struct inet6_dev *in6_dev = __in6_dev_get(dev);
struct smc_clc_ipv6_prefix *ipv6_prfx;
struct inet6_ifaddr *ifa;
int i, max;
if (!in6_dev)
return -ENODEV;
/* ipv6 prefix list starts behind smc_clc_msg_proposal_prefix */
ipv6_prfx = (struct smc_clc_ipv6_prefix *)((u8 *)prop + sizeof(*prop));
max = min_t(u8, prop->ipv6_prefixes_cnt, SMC_CLC_MAX_V6_PREFIX);
list_for_each_entry(ifa, &in6_dev->addr_list, if_list) {
if (ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)
continue;
for (i = 0; i < max; i++) {
if (ifa->prefix_len == ipv6_prfx[i].prefix_len &&
ipv6_prefix_equal(&ifa->addr, &ipv6_prfx[i].prefix,
ifa->prefix_len))
return 0;
}
}
#endif
return -ENOENT;
}
/* check if proposed prefixes match one of our device prefixes */
int smc_clc_prfx_match(struct socket *clcsock,
struct smc_clc_msg_proposal_prefix *prop)
{
struct dst_entry *dst = sk_dst_get(clcsock->sk);
int rc;
if (!dst) {
rc = -ENOTCONN;
goto out;
}
if (!dst->dev) {
rc = -ENODEV;
goto out_rel;
}
rcu_read_lock();
if (!prop->ipv6_prefixes_cnt)
rc = smc_clc_prfx_match4_rcu(dst->dev, prop);
else
rc = smc_clc_prfx_match6_rcu(dst->dev, prop);
rcu_read_unlock();
out_rel:
dst_release(dst);
out:
return rc;
}
/* Wait for data on the tcp-socket, analyze received data
* Returns:
* 0 if success and it was not a decline that we received.
* SMC_CLC_DECL_REPLY if decline received for fallback w/o another decl send.
* clcsock error, -EINTR, -ECONNRESET, -EPROTO otherwise.
*/
int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
u8 expected_type)
{
struct sock *clc_sk = smc->clcsock->sk;
struct smc_clc_msg_hdr *clcm = buf;
struct msghdr msg = {NULL, 0};
int reason_code = 0;
struct kvec vec = {buf, buflen};
int len, datlen;
int krflags;
/* peek the first few bytes to determine length of data to receive
* so we don't consume any subsequent CLC message or payload data
* in the TCP byte stream
*/
/*
* Caller must make sure that buflen is no less than
* sizeof(struct smc_clc_msg_hdr)
*/
krflags = MSG_PEEK | MSG_WAITALL;
smc->clcsock->sk->sk_rcvtimeo = CLC_WAIT_TIME;
iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &vec, 1,
sizeof(struct smc_clc_msg_hdr));
len = sock_recvmsg(smc->clcsock, &msg, krflags);
if (signal_pending(current)) {
reason_code = -EINTR;
clc_sk->sk_err = EINTR;
smc->sk.sk_err = EINTR;
goto out;
}
if (clc_sk->sk_err) {
reason_code = -clc_sk->sk_err;
smc->sk.sk_err = clc_sk->sk_err;
goto out;
}
if (!len) { /* peer has performed orderly shutdown */
smc->sk.sk_err = ECONNRESET;
reason_code = -ECONNRESET;
goto out;
}
if (len < 0) {
smc->sk.sk_err = -len;
reason_code = len;
goto out;
}
datlen = ntohs(clcm->length);
if ((len < sizeof(struct smc_clc_msg_hdr)) ||
(datlen > buflen) ||
((clcm->type != SMC_CLC_DECLINE) &&
(clcm->type != expected_type))) {
smc->sk.sk_err = EPROTO;
reason_code = -EPROTO;
goto out;
}
/* receive the complete CLC message */
memset(&msg, 0, sizeof(struct msghdr));
iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &vec, 1, datlen);
krflags = MSG_WAITALL;
smc->clcsock->sk->sk_rcvtimeo = CLC_WAIT_TIME;
len = sock_recvmsg(smc->clcsock, &msg, krflags);
if (len < datlen || !smc_clc_msg_hdr_valid(clcm)) {
smc->sk.sk_err = EPROTO;
reason_code = -EPROTO;
goto out;
}
if (clcm->type == SMC_CLC_DECLINE) {
reason_code = SMC_CLC_DECL_REPLY;
if (((struct smc_clc_msg_decline *)buf)->hdr.flag) {
smc->conn.lgr->sync_err = true;
smc_lgr_terminate(smc->conn.lgr);
}
}
out:
return reason_code;
}
/* send CLC DECLINE message across internal TCP socket */
int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info)
{
struct smc_clc_msg_decline dclc;
struct msghdr msg;
struct kvec vec;
int len;
memset(&dclc, 0, sizeof(dclc));
memcpy(dclc.hdr.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
dclc.hdr.type = SMC_CLC_DECLINE;
dclc.hdr.length = htons(sizeof(struct smc_clc_msg_decline));
dclc.hdr.version = SMC_CLC_V1;
dclc.hdr.flag = (peer_diag_info == SMC_CLC_DECL_SYNCERR) ? 1 : 0;
memcpy(dclc.id_for_peer, local_systemid, sizeof(local_systemid));
dclc.peer_diagnosis = htonl(peer_diag_info);
memcpy(dclc.trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
memset(&msg, 0, sizeof(msg));
vec.iov_base = &dclc;
vec.iov_len = sizeof(struct smc_clc_msg_decline);
len = kernel_sendmsg(smc->clcsock, &msg, &vec, 1,
sizeof(struct smc_clc_msg_decline));
if (len < sizeof(struct smc_clc_msg_decline))
smc->sk.sk_err = EPROTO;
if (len < 0)
smc->sk.sk_err = -len;
return sock_error(&smc->sk);
}
/* send CLC PROPOSAL message across internal TCP socket */
int smc_clc_send_proposal(struct smc_sock *smc,
struct smc_ib_device *smcibdev,
u8 ibport)
{
struct smc_clc_ipv6_prefix ipv6_prfx[SMC_CLC_MAX_V6_PREFIX];
struct smc_clc_msg_proposal_prefix pclc_prfx;
struct smc_clc_msg_proposal pclc;
struct smc_clc_msg_trail trl;
int len, i, plen, rc;
int reason_code = 0;
struct kvec vec[4];
struct msghdr msg;
/* retrieve ip prefixes for CLC proposal msg */
rc = smc_clc_prfx_set(smc->clcsock, &pclc_prfx, ipv6_prfx);
if (rc)
return SMC_CLC_DECL_CNFERR; /* configuration error */
/* send SMC Proposal CLC message */
plen = sizeof(pclc) + sizeof(pclc_prfx) +
(pclc_prfx.ipv6_prefixes_cnt * sizeof(ipv6_prfx[0])) +
sizeof(trl);
memset(&pclc, 0, sizeof(pclc));
memcpy(pclc.hdr.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
pclc.hdr.type = SMC_CLC_PROPOSAL;
pclc.hdr.length = htons(plen);
pclc.hdr.version = SMC_CLC_V1; /* SMC version */
memcpy(pclc.lcl.id_for_peer, local_systemid, sizeof(local_systemid));
memcpy(&pclc.lcl.gid, &smcibdev->gid[ibport - 1], SMC_GID_SIZE);
memcpy(&pclc.lcl.mac, &smcibdev->mac[ibport - 1], ETH_ALEN);
pclc.iparea_offset = htons(0);
memcpy(trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
memset(&msg, 0, sizeof(msg));
i = 0;
vec[i].iov_base = &pclc;
vec[i++].iov_len = sizeof(pclc);
vec[i].iov_base = &pclc_prfx;
vec[i++].iov_len = sizeof(pclc_prfx);
if (pclc_prfx.ipv6_prefixes_cnt > 0) {
vec[i].iov_base = &ipv6_prfx[0];
vec[i++].iov_len = pclc_prfx.ipv6_prefixes_cnt *
sizeof(ipv6_prfx[0]);
}
vec[i].iov_base = &trl;
vec[i++].iov_len = sizeof(trl);
/* due to the few bytes needed for clc-handshake this cannot block */
len = kernel_sendmsg(smc->clcsock, &msg, vec, i, plen);
if (len < sizeof(pclc)) {
if (len >= 0) {
reason_code = -ENETUNREACH;
smc->sk.sk_err = -reason_code;
} else {
smc->sk.sk_err = smc->clcsock->sk->sk_err;
reason_code = -smc->sk.sk_err;
}
}
return reason_code;
}
/* send CLC CONFIRM message across internal TCP socket */
int smc_clc_send_confirm(struct smc_sock *smc)
{
struct smc_connection *conn = &smc->conn;
struct smc_clc_msg_accept_confirm cclc;
struct smc_link *link;
int reason_code = 0;
struct msghdr msg;
struct kvec vec;
int len;
link = &conn->lgr->lnk[SMC_SINGLE_LINK];
/* send SMC Confirm CLC msg */
memset(&cclc, 0, sizeof(cclc));
memcpy(cclc.hdr.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
cclc.hdr.type = SMC_CLC_CONFIRM;
cclc.hdr.length = htons(sizeof(cclc));
cclc.hdr.version = SMC_CLC_V1; /* SMC version */
memcpy(cclc.lcl.id_for_peer, local_systemid, sizeof(local_systemid));
memcpy(&cclc.lcl.gid, &link->smcibdev->gid[link->ibport - 1],
SMC_GID_SIZE);
memcpy(&cclc.lcl.mac, &link->smcibdev->mac[link->ibport - 1], ETH_ALEN);
hton24(cclc.qpn, link->roce_qp->qp_num);
cclc.rmb_rkey =
htonl(conn->rmb_desc->mr_rx[SMC_SINGLE_LINK]->rkey);
cclc.conn_idx = 1; /* for now: 1 RMB = 1 RMBE */
cclc.rmbe_alert_token = htonl(conn->alert_token_local);
cclc.qp_mtu = min(link->path_mtu, link->peer_mtu);
cclc.rmbe_size = conn->rmbe_size_short;
cclc.rmb_dma_addr = cpu_to_be64(
(u64)sg_dma_address(conn->rmb_desc->sgt[SMC_SINGLE_LINK].sgl));
hton24(cclc.psn, link->psn_initial);
memcpy(cclc.trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
memset(&msg, 0, sizeof(msg));
vec.iov_base = &cclc;
vec.iov_len = sizeof(cclc);
len = kernel_sendmsg(smc->clcsock, &msg, &vec, 1, sizeof(cclc));
if (len < sizeof(cclc)) {
if (len >= 0) {
reason_code = -ENETUNREACH;
smc->sk.sk_err = -reason_code;
} else {
smc->sk.sk_err = smc->clcsock->sk->sk_err;
reason_code = -smc->sk.sk_err;
}
}
return reason_code;
}
/* send CLC ACCEPT message across internal TCP socket */
int smc_clc_send_accept(struct smc_sock *new_smc, int srv_first_contact)
{
struct smc_connection *conn = &new_smc->conn;
struct smc_clc_msg_accept_confirm aclc;
struct smc_link *link;
struct msghdr msg;
struct kvec vec;
int rc = 0;
int len;
link = &conn->lgr->lnk[SMC_SINGLE_LINK];
memset(&aclc, 0, sizeof(aclc));
memcpy(aclc.hdr.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
aclc.hdr.type = SMC_CLC_ACCEPT;
aclc.hdr.length = htons(sizeof(aclc));
aclc.hdr.version = SMC_CLC_V1; /* SMC version */
if (srv_first_contact)
aclc.hdr.flag = 1;
memcpy(aclc.lcl.id_for_peer, local_systemid, sizeof(local_systemid));
memcpy(&aclc.lcl.gid, &link->smcibdev->gid[link->ibport - 1],
SMC_GID_SIZE);
memcpy(&aclc.lcl.mac, link->smcibdev->mac[link->ibport - 1], ETH_ALEN);
hton24(aclc.qpn, link->roce_qp->qp_num);
aclc.rmb_rkey =
htonl(conn->rmb_desc->mr_rx[SMC_SINGLE_LINK]->rkey);
aclc.conn_idx = 1; /* as long as 1 RMB = 1 RMBE */
aclc.rmbe_alert_token = htonl(conn->alert_token_local);
aclc.qp_mtu = link->path_mtu;
aclc.rmbe_size = conn->rmbe_size_short,
aclc.rmb_dma_addr = cpu_to_be64(
(u64)sg_dma_address(conn->rmb_desc->sgt[SMC_SINGLE_LINK].sgl));
hton24(aclc.psn, link->psn_initial);
memcpy(aclc.trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
memset(&msg, 0, sizeof(msg));
vec.iov_base = &aclc;
vec.iov_len = sizeof(aclc);
len = kernel_sendmsg(new_smc->clcsock, &msg, &vec, 1, sizeof(aclc));
if (len < sizeof(aclc)) {
if (len >= 0)
new_smc->sk.sk_err = EPROTO;
else
new_smc->sk.sk_err = new_smc->clcsock->sk->sk_err;
rc = sock_error(&new_smc->sk);
}
return rc;
}