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linux/net/smc/smc_core.c
D. Wythe aff7bfed90 net/smc: replace mutex rmbs_lock and sndbufs_lock with rw_semaphore 
It's clear that rmbs_lock and sndbufs_lock are aims to protect the
rmbs list or the sndbufs list.

During connection establieshment, smc_buf_get_slot() will always
be invoked, and it only performs read semantics in rmbs list and
sndbufs list.

Based on the above considerations, we replace mutex with rw_semaphore.
Only smc_buf_get_slot() use down_read() to allow smc_buf_get_slot()
run concurrently, other part use down_write() to keep exclusive
semantics.

Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-02-04 09:48:19 +00:00

2622 lines
68 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0
/*
* Shared Memory Communications over RDMA (SMC-R) and RoCE
*
* Basic Transport Functions exploiting Infiniband API
*
* Copyright IBM Corp. 2016
*
* Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
*/
#include <linux/socket.h>
#include <linux/if_vlan.h>
#include <linux/random.h>
#include <linux/workqueue.h>
#include <linux/wait.h>
#include <linux/reboot.h>
#include <linux/mutex.h>
#include <linux/list.h>
#include <linux/smc.h>
#include <net/tcp.h>
#include <net/sock.h>
#include <rdma/ib_verbs.h>
#include <rdma/ib_cache.h>
#include "smc.h"
#include "smc_clc.h"
#include "smc_core.h"
#include "smc_ib.h"
#include "smc_wr.h"
#include "smc_llc.h"
#include "smc_cdc.h"
#include "smc_close.h"
#include "smc_ism.h"
#include "smc_netlink.h"
#include "smc_stats.h"
#include "smc_tracepoint.h"
#define SMC_LGR_NUM_INCR 256
#define SMC_LGR_FREE_DELAY_SERV (600 * HZ)
#define SMC_LGR_FREE_DELAY_CLNT (SMC_LGR_FREE_DELAY_SERV + 10 * HZ)
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),
.num = 0,
};
static atomic_t lgr_cnt = ATOMIC_INIT(0); /* number of existing link groups */
static DECLARE_WAIT_QUEUE_HEAD(lgrs_deleted);
static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
struct smc_buf_desc *buf_desc);
static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft);
static void smc_link_down_work(struct work_struct *work);
/* return head of link group list and its lock for a given link group */
static inline struct list_head *smc_lgr_list_head(struct smc_link_group *lgr,
spinlock_t **lgr_lock)
{
if (lgr->is_smcd) {
*lgr_lock = &lgr->smcd->lgr_lock;
return &lgr->smcd->lgr_list;
}
*lgr_lock = &smc_lgr_list.lock;
return &smc_lgr_list.list;
}
static void smc_ibdev_cnt_inc(struct smc_link *lnk)
{
atomic_inc(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
}
static void smc_ibdev_cnt_dec(struct smc_link *lnk)
{
atomic_dec(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
}
static void smc_lgr_schedule_free_work(struct smc_link_group *lgr)
{
/* client link group creation always follows the server link group
* creation. For client use a somewhat higher removal delay time,
* otherwise there is a risk of out-of-sync link groups.
*/
if (!lgr->freeing) {
mod_delayed_work(system_wq, &lgr->free_work,
(!lgr->is_smcd && lgr->role == SMC_CLNT) ?
SMC_LGR_FREE_DELAY_CLNT :
SMC_LGR_FREE_DELAY_SERV);
}
}
/* Register connection's alert token in our lookup structure.
* To use rbtrees we have to implement our own insert core.
* Requires @conns_lock
* @smc connection to register
* Returns 0 on success, != otherwise.
*/
static void smc_lgr_add_alert_token(struct smc_connection *conn)
{
struct rb_node **link, *parent = NULL;
u32 token = conn->alert_token_local;
link = &conn->lgr->conns_all.rb_node;
while (*link) {
struct smc_connection *cur = rb_entry(*link,
struct smc_connection, alert_node);
parent = *link;
if (cur->alert_token_local > token)
link = &parent->rb_left;
else
link = &parent->rb_right;
}
/* Put the new node there */
rb_link_node(&conn->alert_node, parent, link);
rb_insert_color(&conn->alert_node, &conn->lgr->conns_all);
}
/* assign an SMC-R link to the connection */
static int smcr_lgr_conn_assign_link(struct smc_connection *conn, bool first)
{
enum smc_link_state expected = first ? SMC_LNK_ACTIVATING :
SMC_LNK_ACTIVE;
int i, j;
/* do link balancing */
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
struct smc_link *lnk = &conn->lgr->lnk[i];
if (lnk->state != expected || lnk->link_is_asym)
continue;
if (conn->lgr->role == SMC_CLNT) {
conn->lnk = lnk; /* temporary, SMC server assigns link*/
break;
}
if (conn->lgr->conns_num % 2) {
for (j = i + 1; j < SMC_LINKS_PER_LGR_MAX; j++) {
struct smc_link *lnk2;
lnk2 = &conn->lgr->lnk[j];
if (lnk2->state == expected &&
!lnk2->link_is_asym) {
conn->lnk = lnk2;
break;
}
}
}
if (!conn->lnk)
conn->lnk = lnk;
break;
}
if (!conn->lnk)
return SMC_CLC_DECL_NOACTLINK;
atomic_inc(&conn->lnk->conn_cnt);
return 0;
}
/* Register connection in link group by assigning an alert token
* registered in a search tree.
* Requires @conns_lock
* Note that '0' is a reserved value and not assigned.
*/
static int smc_lgr_register_conn(struct smc_connection *conn, bool first)
{
struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
static atomic_t nexttoken = ATOMIC_INIT(0);
int rc;
if (!conn->lgr->is_smcd) {
rc = smcr_lgr_conn_assign_link(conn, first);
if (rc) {
conn->lgr = NULL;
return rc;
}
}
/* find a new alert_token_local value not yet used by some connection
* in this link group
*/
sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */
while (!conn->alert_token_local) {
conn->alert_token_local = atomic_inc_return(&nexttoken);
if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr))
conn->alert_token_local = 0;
}
smc_lgr_add_alert_token(conn);
conn->lgr->conns_num++;
return 0;
}
/* Unregister connection and reset the alert token of the given connection<
*/
static void __smc_lgr_unregister_conn(struct smc_connection *conn)
{
struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
struct smc_link_group *lgr = conn->lgr;
rb_erase(&conn->alert_node, &lgr->conns_all);
if (conn->lnk)
atomic_dec(&conn->lnk->conn_cnt);
lgr->conns_num--;
conn->alert_token_local = 0;
sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */
}
/* Unregister connection from lgr
*/
static void smc_lgr_unregister_conn(struct smc_connection *conn)
{
struct smc_link_group *lgr = conn->lgr;
if (!smc_conn_lgr_valid(conn))
return;
write_lock_bh(&lgr->conns_lock);
if (conn->alert_token_local) {
__smc_lgr_unregister_conn(conn);
}
write_unlock_bh(&lgr->conns_lock);
}
int smc_nl_get_sys_info(struct sk_buff *skb, struct netlink_callback *cb)
{
struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
char hostname[SMC_MAX_HOSTNAME_LEN + 1];
char smc_seid[SMC_MAX_EID_LEN + 1];
struct nlattr *attrs;
u8 *seid = NULL;
u8 *host = NULL;
void *nlh;
nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
&smc_gen_nl_family, NLM_F_MULTI,
SMC_NETLINK_GET_SYS_INFO);
if (!nlh)
goto errmsg;
if (cb_ctx->pos[0])
goto errout;
attrs = nla_nest_start(skb, SMC_GEN_SYS_INFO);
if (!attrs)
goto errout;
if (nla_put_u8(skb, SMC_NLA_SYS_VER, SMC_V2))
goto errattr;
if (nla_put_u8(skb, SMC_NLA_SYS_REL, SMC_RELEASE))
goto errattr;
if (nla_put_u8(skb, SMC_NLA_SYS_IS_ISM_V2, smc_ism_is_v2_capable()))
goto errattr;
if (nla_put_u8(skb, SMC_NLA_SYS_IS_SMCR_V2, true))
goto errattr;
smc_clc_get_hostname(&host);
if (host) {
memcpy(hostname, host, SMC_MAX_HOSTNAME_LEN);
hostname[SMC_MAX_HOSTNAME_LEN] = 0;
if (nla_put_string(skb, SMC_NLA_SYS_LOCAL_HOST, hostname))
goto errattr;
}
if (smc_ism_is_v2_capable()) {
smc_ism_get_system_eid(&seid);
memcpy(smc_seid, seid, SMC_MAX_EID_LEN);
smc_seid[SMC_MAX_EID_LEN] = 0;
if (nla_put_string(skb, SMC_NLA_SYS_SEID, smc_seid))
goto errattr;
}
nla_nest_end(skb, attrs);
genlmsg_end(skb, nlh);
cb_ctx->pos[0] = 1;
return skb->len;
errattr:
nla_nest_cancel(skb, attrs);
errout:
genlmsg_cancel(skb, nlh);
errmsg:
return skb->len;
}
/* Fill SMC_NLA_LGR_D_V2_COMMON/SMC_NLA_LGR_R_V2_COMMON nested attributes */
static int smc_nl_fill_lgr_v2_common(struct smc_link_group *lgr,
struct sk_buff *skb,
struct netlink_callback *cb,
struct nlattr *v2_attrs)
{
char smc_host[SMC_MAX_HOSTNAME_LEN + 1];
char smc_eid[SMC_MAX_EID_LEN + 1];
if (nla_put_u8(skb, SMC_NLA_LGR_V2_VER, lgr->smc_version))
goto errv2attr;
if (nla_put_u8(skb, SMC_NLA_LGR_V2_REL, lgr->peer_smc_release))
goto errv2attr;
if (nla_put_u8(skb, SMC_NLA_LGR_V2_OS, lgr->peer_os))
goto errv2attr;
memcpy(smc_host, lgr->peer_hostname, SMC_MAX_HOSTNAME_LEN);
smc_host[SMC_MAX_HOSTNAME_LEN] = 0;
if (nla_put_string(skb, SMC_NLA_LGR_V2_PEER_HOST, smc_host))
goto errv2attr;
memcpy(smc_eid, lgr->negotiated_eid, SMC_MAX_EID_LEN);
smc_eid[SMC_MAX_EID_LEN] = 0;
if (nla_put_string(skb, SMC_NLA_LGR_V2_NEG_EID, smc_eid))
goto errv2attr;
nla_nest_end(skb, v2_attrs);
return 0;
errv2attr:
nla_nest_cancel(skb, v2_attrs);
return -EMSGSIZE;
}
static int smc_nl_fill_smcr_lgr_v2(struct smc_link_group *lgr,
struct sk_buff *skb,
struct netlink_callback *cb)
{
struct nlattr *v2_attrs;
v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2);
if (!v2_attrs)
goto errattr;
if (nla_put_u8(skb, SMC_NLA_LGR_R_V2_DIRECT, !lgr->uses_gateway))
goto errv2attr;
nla_nest_end(skb, v2_attrs);
return 0;
errv2attr:
nla_nest_cancel(skb, v2_attrs);
errattr:
return -EMSGSIZE;
}
static int smc_nl_fill_lgr(struct smc_link_group *lgr,
struct sk_buff *skb,
struct netlink_callback *cb)
{
char smc_target[SMC_MAX_PNETID_LEN + 1];
struct nlattr *attrs, *v2_attrs;
attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCR);
if (!attrs)
goto errout;
if (nla_put_u32(skb, SMC_NLA_LGR_R_ID, *((u32 *)&lgr->id)))
goto errattr;
if (nla_put_u32(skb, SMC_NLA_LGR_R_CONNS_NUM, lgr->conns_num))
goto errattr;
if (nla_put_u8(skb, SMC_NLA_LGR_R_ROLE, lgr->role))
goto errattr;
if (nla_put_u8(skb, SMC_NLA_LGR_R_TYPE, lgr->type))
goto errattr;
if (nla_put_u8(skb, SMC_NLA_LGR_R_BUF_TYPE, lgr->buf_type))
goto errattr;
if (nla_put_u8(skb, SMC_NLA_LGR_R_VLAN_ID, lgr->vlan_id))
goto errattr;
if (nla_put_u64_64bit(skb, SMC_NLA_LGR_R_NET_COOKIE,
lgr->net->net_cookie, SMC_NLA_LGR_R_PAD))
goto errattr;
memcpy(smc_target, lgr->pnet_id, SMC_MAX_PNETID_LEN);
smc_target[SMC_MAX_PNETID_LEN] = 0;
if (nla_put_string(skb, SMC_NLA_LGR_R_PNETID, smc_target))
goto errattr;
if (lgr->smc_version > SMC_V1) {
v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2_COMMON);
if (!v2_attrs)
goto errattr;
if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
goto errattr;
if (smc_nl_fill_smcr_lgr_v2(lgr, skb, cb))
goto errattr;
}
nla_nest_end(skb, attrs);
return 0;
errattr:
nla_nest_cancel(skb, attrs);
errout:
return -EMSGSIZE;
}
static int smc_nl_fill_lgr_link(struct smc_link_group *lgr,
struct smc_link *link,
struct sk_buff *skb,
struct netlink_callback *cb)
{
char smc_ibname[IB_DEVICE_NAME_MAX];
u8 smc_gid_target[41];
struct nlattr *attrs;
u32 link_uid = 0;
void *nlh;
nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
&smc_gen_nl_family, NLM_F_MULTI,
SMC_NETLINK_GET_LINK_SMCR);
if (!nlh)
goto errmsg;
attrs = nla_nest_start(skb, SMC_GEN_LINK_SMCR);
if (!attrs)
goto errout;
if (nla_put_u8(skb, SMC_NLA_LINK_ID, link->link_id))
goto errattr;
if (nla_put_u32(skb, SMC_NLA_LINK_STATE, link->state))
goto errattr;
if (nla_put_u32(skb, SMC_NLA_LINK_CONN_CNT,
atomic_read(&link->conn_cnt)))
goto errattr;
if (nla_put_u8(skb, SMC_NLA_LINK_IB_PORT, link->ibport))
goto errattr;
if (nla_put_u32(skb, SMC_NLA_LINK_NET_DEV, link->ndev_ifidx))
goto errattr;
snprintf(smc_ibname, sizeof(smc_ibname), "%s", link->ibname);
if (nla_put_string(skb, SMC_NLA_LINK_IB_DEV, smc_ibname))
goto errattr;
memcpy(&link_uid, link->link_uid, sizeof(link_uid));
if (nla_put_u32(skb, SMC_NLA_LINK_UID, link_uid))
goto errattr;
memcpy(&link_uid, link->peer_link_uid, sizeof(link_uid));
if (nla_put_u32(skb, SMC_NLA_LINK_PEER_UID, link_uid))
goto errattr;
memset(smc_gid_target, 0, sizeof(smc_gid_target));
smc_gid_be16_convert(smc_gid_target, link->gid);
if (nla_put_string(skb, SMC_NLA_LINK_GID, smc_gid_target))
goto errattr;
memset(smc_gid_target, 0, sizeof(smc_gid_target));
smc_gid_be16_convert(smc_gid_target, link->peer_gid);
if (nla_put_string(skb, SMC_NLA_LINK_PEER_GID, smc_gid_target))
goto errattr;
nla_nest_end(skb, attrs);
genlmsg_end(skb, nlh);
return 0;
errattr:
nla_nest_cancel(skb, attrs);
errout:
genlmsg_cancel(skb, nlh);
errmsg:
return -EMSGSIZE;
}
static int smc_nl_handle_lgr(struct smc_link_group *lgr,
struct sk_buff *skb,
struct netlink_callback *cb,
bool list_links)
{
void *nlh;
int i;
nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
&smc_gen_nl_family, NLM_F_MULTI,
SMC_NETLINK_GET_LGR_SMCR);
if (!nlh)
goto errmsg;
if (smc_nl_fill_lgr(lgr, skb, cb))
goto errout;
genlmsg_end(skb, nlh);
if (!list_links)
goto out;
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
if (!smc_link_usable(&lgr->lnk[i]))
continue;
if (smc_nl_fill_lgr_link(lgr, &lgr->lnk[i], skb, cb))
goto errout;
}
out:
return 0;
errout:
genlmsg_cancel(skb, nlh);
errmsg:
return -EMSGSIZE;
}
static void smc_nl_fill_lgr_list(struct smc_lgr_list *smc_lgr,
struct sk_buff *skb,
struct netlink_callback *cb,
bool list_links)
{
struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
struct smc_link_group *lgr;
int snum = cb_ctx->pos[0];
int num = 0;
spin_lock_bh(&smc_lgr->lock);
list_for_each_entry(lgr, &smc_lgr->list, list) {
if (num < snum)
goto next;
if (smc_nl_handle_lgr(lgr, skb, cb, list_links))
goto errout;
next:
num++;
}
errout:
spin_unlock_bh(&smc_lgr->lock);
cb_ctx->pos[0] = num;
}
static int smc_nl_fill_smcd_lgr(struct smc_link_group *lgr,
struct sk_buff *skb,
struct netlink_callback *cb)
{
char smc_pnet[SMC_MAX_PNETID_LEN + 1];
struct smcd_dev *smcd = lgr->smcd;
struct nlattr *attrs;
void *nlh;
nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
&smc_gen_nl_family, NLM_F_MULTI,
SMC_NETLINK_GET_LGR_SMCD);
if (!nlh)
goto errmsg;
attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCD);
if (!attrs)
goto errout;
if (nla_put_u32(skb, SMC_NLA_LGR_D_ID, *((u32 *)&lgr->id)))
goto errattr;
if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_GID,
smcd->ops->get_local_gid(smcd),
SMC_NLA_LGR_D_PAD))
goto errattr;
if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_GID, lgr->peer_gid,
SMC_NLA_LGR_D_PAD))
goto errattr;
if (nla_put_u8(skb, SMC_NLA_LGR_D_VLAN_ID, lgr->vlan_id))
goto errattr;
if (nla_put_u32(skb, SMC_NLA_LGR_D_CONNS_NUM, lgr->conns_num))
goto errattr;
if (nla_put_u32(skb, SMC_NLA_LGR_D_CHID, smc_ism_get_chid(lgr->smcd)))
goto errattr;
memcpy(smc_pnet, lgr->smcd->pnetid, SMC_MAX_PNETID_LEN);
smc_pnet[SMC_MAX_PNETID_LEN] = 0;
if (nla_put_string(skb, SMC_NLA_LGR_D_PNETID, smc_pnet))
goto errattr;
if (lgr->smc_version > SMC_V1) {
struct nlattr *v2_attrs;
v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_D_V2_COMMON);
if (!v2_attrs)
goto errattr;
if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
goto errattr;
}
nla_nest_end(skb, attrs);
genlmsg_end(skb, nlh);
return 0;
errattr:
nla_nest_cancel(skb, attrs);
errout:
genlmsg_cancel(skb, nlh);
errmsg:
return -EMSGSIZE;
}
static int smc_nl_handle_smcd_lgr(struct smcd_dev *dev,
struct sk_buff *skb,
struct netlink_callback *cb)
{
struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
struct smc_link_group *lgr;
int snum = cb_ctx->pos[1];
int rc = 0, num = 0;
spin_lock_bh(&dev->lgr_lock);
list_for_each_entry(lgr, &dev->lgr_list, list) {
if (!lgr->is_smcd)
continue;
if (num < snum)
goto next;
rc = smc_nl_fill_smcd_lgr(lgr, skb, cb);
if (rc)
goto errout;
next:
num++;
}
errout:
spin_unlock_bh(&dev->lgr_lock);
cb_ctx->pos[1] = num;
return rc;
}
static int smc_nl_fill_smcd_dev(struct smcd_dev_list *dev_list,
struct sk_buff *skb,
struct netlink_callback *cb)
{
struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
struct smcd_dev *smcd_dev;
int snum = cb_ctx->pos[0];
int rc = 0, num = 0;
mutex_lock(&dev_list->mutex);
list_for_each_entry(smcd_dev, &dev_list->list, list) {
if (list_empty(&smcd_dev->lgr_list))
continue;
if (num < snum)
goto next;
rc = smc_nl_handle_smcd_lgr(smcd_dev, skb, cb);
if (rc)
goto errout;
next:
num++;
}
errout:
mutex_unlock(&dev_list->mutex);
cb_ctx->pos[0] = num;
return rc;
}
int smcr_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
{
bool list_links = false;
smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
return skb->len;
}
int smcr_nl_get_link(struct sk_buff *skb, struct netlink_callback *cb)
{
bool list_links = true;
smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
return skb->len;
}
int smcd_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
{
smc_nl_fill_smcd_dev(&smcd_dev_list, skb, cb);
return skb->len;
}
void smc_lgr_cleanup_early(struct smc_link_group *lgr)
{
spinlock_t *lgr_lock;
if (!lgr)
return;
smc_lgr_list_head(lgr, &lgr_lock);
spin_lock_bh(lgr_lock);
/* do not use this link group for new connections */
if (!list_empty(&lgr->list))
list_del_init(&lgr->list);
spin_unlock_bh(lgr_lock);
__smc_lgr_terminate(lgr, true);
}
static void smcr_lgr_link_deactivate_all(struct smc_link_group *lgr)
{
int i;
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
struct smc_link *lnk = &lgr->lnk[i];
if (smc_link_sendable(lnk))
lnk->state = SMC_LNK_INACTIVE;
}
wake_up_all(&lgr->llc_msg_waiter);
wake_up_all(&lgr->llc_flow_waiter);
}
static void smc_lgr_free(struct smc_link_group *lgr);
static void smc_lgr_free_work(struct work_struct *work)
{
struct smc_link_group *lgr = container_of(to_delayed_work(work),
struct smc_link_group,
free_work);
spinlock_t *lgr_lock;
bool conns;
smc_lgr_list_head(lgr, &lgr_lock);
spin_lock_bh(lgr_lock);
if (lgr->freeing) {
spin_unlock_bh(lgr_lock);
return;
}
read_lock_bh(&lgr->conns_lock);
conns = RB_EMPTY_ROOT(&lgr->conns_all);
read_unlock_bh(&lgr->conns_lock);
if (!conns) { /* number of lgr connections is no longer zero */
spin_unlock_bh(lgr_lock);
return;
}
list_del_init(&lgr->list); /* remove from smc_lgr_list */
lgr->freeing = 1; /* this instance does the freeing, no new schedule */
spin_unlock_bh(lgr_lock);
cancel_delayed_work(&lgr->free_work);
if (!lgr->is_smcd && !lgr->terminating)
smc_llc_send_link_delete_all(lgr, true,
SMC_LLC_DEL_PROG_INIT_TERM);
if (lgr->is_smcd && !lgr->terminating)
smc_ism_signal_shutdown(lgr);
if (!lgr->is_smcd)
smcr_lgr_link_deactivate_all(lgr);
smc_lgr_free(lgr);
}
static void smc_lgr_terminate_work(struct work_struct *work)
{
struct smc_link_group *lgr = container_of(work, struct smc_link_group,
terminate_work);
__smc_lgr_terminate(lgr, true);
}
/* return next unique link id for the lgr */
static u8 smcr_next_link_id(struct smc_link_group *lgr)
{
u8 link_id;
int i;
while (1) {
again:
link_id = ++lgr->next_link_id;
if (!link_id) /* skip zero as link_id */
link_id = ++lgr->next_link_id;
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
if (smc_link_usable(&lgr->lnk[i]) &&
lgr->lnk[i].link_id == link_id)
goto again;
}
break;
}
return link_id;
}
static void smcr_copy_dev_info_to_link(struct smc_link *link)
{
struct smc_ib_device *smcibdev = link->smcibdev;
snprintf(link->ibname, sizeof(link->ibname), "%s",
smcibdev->ibdev->name);
link->ndev_ifidx = smcibdev->ndev_ifidx[link->ibport - 1];
}
int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
u8 link_idx, struct smc_init_info *ini)
{
struct smc_ib_device *smcibdev;
u8 rndvec[3];
int rc;
if (lgr->smc_version == SMC_V2) {
lnk->smcibdev = ini->smcrv2.ib_dev_v2;
lnk->ibport = ini->smcrv2.ib_port_v2;
} else {
lnk->smcibdev = ini->ib_dev;
lnk->ibport = ini->ib_port;
}
get_device(&lnk->smcibdev->ibdev->dev);
atomic_inc(&lnk->smcibdev->lnk_cnt);
refcount_set(&lnk->refcnt, 1); /* link refcnt is set to 1 */
lnk->clearing = 0;
lnk->path_mtu = lnk->smcibdev->pattr[lnk->ibport - 1].active_mtu;
lnk->link_id = smcr_next_link_id(lgr);
lnk->lgr = lgr;
smc_lgr_hold(lgr); /* lgr_put in smcr_link_clear() */
lnk->link_idx = link_idx;
lnk->wr_rx_id_compl = 0;
smc_ibdev_cnt_inc(lnk);
smcr_copy_dev_info_to_link(lnk);
atomic_set(&lnk->conn_cnt, 0);
smc_llc_link_set_uid(lnk);
INIT_WORK(&lnk->link_down_wrk, smc_link_down_work);
if (!lnk->smcibdev->initialized) {
rc = (int)smc_ib_setup_per_ibdev(lnk->smcibdev);
if (rc)
goto out;
}
get_random_bytes(rndvec, sizeof(rndvec));
lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) +
(rndvec[2] << 16);
rc = smc_ib_determine_gid(lnk->smcibdev, lnk->ibport,
ini->vlan_id, lnk->gid, &lnk->sgid_index,
lgr->smc_version == SMC_V2 ?
&ini->smcrv2 : NULL);
if (rc)
goto out;
rc = smc_llc_link_init(lnk);
if (rc)
goto out;
rc = smc_wr_alloc_link_mem(lnk);
if (rc)
goto clear_llc_lnk;
rc = smc_ib_create_protection_domain(lnk);
if (rc)
goto free_link_mem;
rc = smc_ib_create_queue_pair(lnk);
if (rc)
goto dealloc_pd;
rc = smc_wr_create_link(lnk);
if (rc)
goto destroy_qp;
lnk->state = SMC_LNK_ACTIVATING;
return 0;
destroy_qp:
smc_ib_destroy_queue_pair(lnk);
dealloc_pd:
smc_ib_dealloc_protection_domain(lnk);
free_link_mem:
smc_wr_free_link_mem(lnk);
clear_llc_lnk:
smc_llc_link_clear(lnk, false);
out:
smc_ibdev_cnt_dec(lnk);
put_device(&lnk->smcibdev->ibdev->dev);
smcibdev = lnk->smcibdev;
memset(lnk, 0, sizeof(struct smc_link));
lnk->state = SMC_LNK_UNUSED;
if (!atomic_dec_return(&smcibdev->lnk_cnt))
wake_up(&smcibdev->lnks_deleted);
smc_lgr_put(lgr); /* lgr_hold above */
return rc;
}
/* create a new SMC link group */
static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
{
struct smc_link_group *lgr;
struct list_head *lgr_list;
struct smcd_dev *smcd;
struct smc_link *lnk;
spinlock_t *lgr_lock;
u8 link_idx;
int rc = 0;
int i;
if (ini->is_smcd && ini->vlan_id) {
if (smc_ism_get_vlan(ini->ism_dev[ini->ism_selected],
ini->vlan_id)) {
rc = SMC_CLC_DECL_ISMVLANERR;
goto out;
}
}
lgr = kzalloc(sizeof(*lgr), GFP_KERNEL);
if (!lgr) {
rc = SMC_CLC_DECL_MEM;
goto ism_put_vlan;
}
lgr->tx_wq = alloc_workqueue("smc_tx_wq-%*phN", 0, 0,
SMC_LGR_ID_SIZE, &lgr->id);
if (!lgr->tx_wq) {
rc = -ENOMEM;
goto free_lgr;
}
lgr->is_smcd = ini->is_smcd;
lgr->sync_err = 0;
lgr->terminating = 0;
lgr->freeing = 0;
lgr->vlan_id = ini->vlan_id;
refcount_set(&lgr->refcnt, 1); /* set lgr refcnt to 1 */
init_rwsem(&lgr->sndbufs_lock);
init_rwsem(&lgr->rmbs_lock);
rwlock_init(&lgr->conns_lock);
for (i = 0; i < SMC_RMBE_SIZES; i++) {
INIT_LIST_HEAD(&lgr->sndbufs[i]);
INIT_LIST_HEAD(&lgr->rmbs[i]);
}
lgr->next_link_id = 0;
smc_lgr_list.num += SMC_LGR_NUM_INCR;
memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE);
INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work);
INIT_WORK(&lgr->terminate_work, smc_lgr_terminate_work);
lgr->conns_all = RB_ROOT;
if (ini->is_smcd) {
/* SMC-D specific settings */
smcd = ini->ism_dev[ini->ism_selected];
get_device(smcd->ops->get_dev(smcd));
lgr->peer_gid = ini->ism_peer_gid[ini->ism_selected];
lgr->smcd = ini->ism_dev[ini->ism_selected];
lgr_list = &ini->ism_dev[ini->ism_selected]->lgr_list;
lgr_lock = &lgr->smcd->lgr_lock;
lgr->smc_version = ini->smcd_version;
lgr->peer_shutdown = 0;
atomic_inc(&ini->ism_dev[ini->ism_selected]->lgr_cnt);
} else {
/* SMC-R specific settings */
struct smc_ib_device *ibdev;
int ibport;
lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
lgr->smc_version = ini->smcr_version;
memcpy(lgr->peer_systemid, ini->peer_systemid,
SMC_SYSTEMID_LEN);
if (lgr->smc_version == SMC_V2) {
ibdev = ini->smcrv2.ib_dev_v2;
ibport = ini->smcrv2.ib_port_v2;
lgr->saddr = ini->smcrv2.saddr;
lgr->uses_gateway = ini->smcrv2.uses_gateway;
memcpy(lgr->nexthop_mac, ini->smcrv2.nexthop_mac,
ETH_ALEN);
} else {
ibdev = ini->ib_dev;
ibport = ini->ib_port;
}
memcpy(lgr->pnet_id, ibdev->pnetid[ibport - 1],
SMC_MAX_PNETID_LEN);
rc = smc_wr_alloc_lgr_mem(lgr);
if (rc)
goto free_wq;
smc_llc_lgr_init(lgr, smc);
link_idx = SMC_SINGLE_LINK;
lnk = &lgr->lnk[link_idx];
rc = smcr_link_init(lgr, lnk, link_idx, ini);
if (rc) {
smc_wr_free_lgr_mem(lgr);
goto free_wq;
}
lgr->net = smc_ib_net(lnk->smcibdev);
lgr_list = &smc_lgr_list.list;
lgr_lock = &smc_lgr_list.lock;
lgr->buf_type = lgr->net->smc.sysctl_smcr_buf_type;
atomic_inc(&lgr_cnt);
}
smc->conn.lgr = lgr;
spin_lock_bh(lgr_lock);
list_add_tail(&lgr->list, lgr_list);
spin_unlock_bh(lgr_lock);
return 0;
free_wq:
destroy_workqueue(lgr->tx_wq);
free_lgr:
kfree(lgr);
ism_put_vlan:
if (ini->is_smcd && ini->vlan_id)
smc_ism_put_vlan(ini->ism_dev[ini->ism_selected], ini->vlan_id);
out:
if (rc < 0) {
if (rc == -ENOMEM)
rc = SMC_CLC_DECL_MEM;
else
rc = SMC_CLC_DECL_INTERR;
}
return rc;
}
static int smc_write_space(struct smc_connection *conn)
{
int buffer_len = conn->peer_rmbe_size;
union smc_host_cursor prod;
union smc_host_cursor cons;
int space;
smc_curs_copy(&prod, &conn->local_tx_ctrl.prod, conn);
smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
/* determine rx_buf space */
space = buffer_len - smc_curs_diff(buffer_len, &cons, &prod);
return space;
}
static int smc_switch_cursor(struct smc_sock *smc, struct smc_cdc_tx_pend *pend,
struct smc_wr_buf *wr_buf)
{
struct smc_connection *conn = &smc->conn;
union smc_host_cursor cons, fin;
int rc = 0;
int diff;
smc_curs_copy(&conn->tx_curs_sent, &conn->tx_curs_fin, conn);
smc_curs_copy(&fin, &conn->local_tx_ctrl_fin, conn);
/* set prod cursor to old state, enforce tx_rdma_writes() */
smc_curs_copy(&conn->local_tx_ctrl.prod, &fin, conn);
smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
if (smc_curs_comp(conn->peer_rmbe_size, &cons, &fin) < 0) {
/* cons cursor advanced more than fin, and prod was set
* fin above, so now prod is smaller than cons. Fix that.
*/
diff = smc_curs_diff(conn->peer_rmbe_size, &fin, &cons);
smc_curs_add(conn->sndbuf_desc->len,
&conn->tx_curs_sent, diff);
smc_curs_add(conn->sndbuf_desc->len,
&conn->tx_curs_fin, diff);
smp_mb__before_atomic();
atomic_add(diff, &conn->sndbuf_space);
smp_mb__after_atomic();
smc_curs_add(conn->peer_rmbe_size,
&conn->local_tx_ctrl.prod, diff);
smc_curs_add(conn->peer_rmbe_size,
&conn->local_tx_ctrl_fin, diff);
}
/* recalculate, value is used by tx_rdma_writes() */
atomic_set(&smc->conn.peer_rmbe_space, smc_write_space(conn));
if (smc->sk.sk_state != SMC_INIT &&
smc->sk.sk_state != SMC_CLOSED) {
rc = smcr_cdc_msg_send_validation(conn, pend, wr_buf);
if (!rc) {
queue_delayed_work(conn->lgr->tx_wq, &conn->tx_work, 0);
smc->sk.sk_data_ready(&smc->sk);
}
} else {
smc_wr_tx_put_slot(conn->lnk,
(struct smc_wr_tx_pend_priv *)pend);
}
return rc;
}
void smc_switch_link_and_count(struct smc_connection *conn,
struct smc_link *to_lnk)
{
atomic_dec(&conn->lnk->conn_cnt);
/* link_hold in smc_conn_create() */
smcr_link_put(conn->lnk);
conn->lnk = to_lnk;
atomic_inc(&conn->lnk->conn_cnt);
/* link_put in smc_conn_free() */
smcr_link_hold(conn->lnk);
}
struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
struct smc_link *from_lnk, bool is_dev_err)
{
struct smc_link *to_lnk = NULL;
struct smc_cdc_tx_pend *pend;
struct smc_connection *conn;
struct smc_wr_buf *wr_buf;
struct smc_sock *smc;
struct rb_node *node;
int i, rc = 0;
/* link is inactive, wake up tx waiters */
smc_wr_wakeup_tx_wait(from_lnk);
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
if (!smc_link_active(&lgr->lnk[i]) || i == from_lnk->link_idx)
continue;
if (is_dev_err && from_lnk->smcibdev == lgr->lnk[i].smcibdev &&
from_lnk->ibport == lgr->lnk[i].ibport) {
continue;
}
to_lnk = &lgr->lnk[i];
break;
}
if (!to_lnk || !smc_wr_tx_link_hold(to_lnk)) {
smc_lgr_terminate_sched(lgr);
return NULL;
}
again:
read_lock_bh(&lgr->conns_lock);
for (node = rb_first(&lgr->conns_all); node; node = rb_next(node)) {
conn = rb_entry(node, struct smc_connection, alert_node);
if (conn->lnk != from_lnk)
continue;
smc = container_of(conn, struct smc_sock, conn);
/* conn->lnk not yet set in SMC_INIT state */
if (smc->sk.sk_state == SMC_INIT)
continue;
if (smc->sk.sk_state == SMC_CLOSED ||
smc->sk.sk_state == SMC_PEERCLOSEWAIT1 ||
smc->sk.sk_state == SMC_PEERCLOSEWAIT2 ||
smc->sk.sk_state == SMC_APPFINCLOSEWAIT ||
smc->sk.sk_state == SMC_APPCLOSEWAIT1 ||
smc->sk.sk_state == SMC_APPCLOSEWAIT2 ||
smc->sk.sk_state == SMC_PEERFINCLOSEWAIT ||
smc->sk.sk_state == SMC_PEERABORTWAIT ||
smc->sk.sk_state == SMC_PROCESSABORT) {
spin_lock_bh(&conn->send_lock);
smc_switch_link_and_count(conn, to_lnk);
spin_unlock_bh(&conn->send_lock);
continue;
}
sock_hold(&smc->sk);
read_unlock_bh(&lgr->conns_lock);
/* pre-fetch buffer outside of send_lock, might sleep */
rc = smc_cdc_get_free_slot(conn, to_lnk, &wr_buf, NULL, &pend);
if (rc)
goto err_out;
/* avoid race with smcr_tx_sndbuf_nonempty() */
spin_lock_bh(&conn->send_lock);
smc_switch_link_and_count(conn, to_lnk);
rc = smc_switch_cursor(smc, pend, wr_buf);
spin_unlock_bh(&conn->send_lock);
sock_put(&smc->sk);
if (rc)
goto err_out;
goto again;
}
read_unlock_bh(&lgr->conns_lock);
smc_wr_tx_link_put(to_lnk);
return to_lnk;
err_out:
smcr_link_down_cond_sched(to_lnk);
smc_wr_tx_link_put(to_lnk);
return NULL;
}
static void smcr_buf_unuse(struct smc_buf_desc *buf_desc, bool is_rmb,
struct smc_link_group *lgr)
{
struct rw_semaphore *lock; /* lock buffer list */
int rc;
if (is_rmb && buf_desc->is_conf_rkey && !list_empty(&lgr->list)) {
/* unregister rmb with peer */
rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
if (!rc) {
/* protect against smc_llc_cli_rkey_exchange() */
down_read(&lgr->llc_conf_mutex);
smc_llc_do_delete_rkey(lgr, buf_desc);
buf_desc->is_conf_rkey = false;
up_read(&lgr->llc_conf_mutex);
smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
}
}
if (buf_desc->is_reg_err) {
/* buf registration failed, reuse not possible */
lock = is_rmb ? &lgr->rmbs_lock :
&lgr->sndbufs_lock;
down_write(lock);
list_del(&buf_desc->list);
up_write(lock);
smc_buf_free(lgr, is_rmb, buf_desc);
} else {
buf_desc->used = 0;
memset(buf_desc->cpu_addr, 0, buf_desc->len);
}
}
static void smc_buf_unuse(struct smc_connection *conn,
struct smc_link_group *lgr)
{
if (conn->sndbuf_desc) {
if (!lgr->is_smcd && conn->sndbuf_desc->is_vm) {
smcr_buf_unuse(conn->sndbuf_desc, false, lgr);
} else {
conn->sndbuf_desc->used = 0;
memset(conn->sndbuf_desc->cpu_addr, 0,
conn->sndbuf_desc->len);
}
}
if (conn->rmb_desc) {
if (!lgr->is_smcd) {
smcr_buf_unuse(conn->rmb_desc, true, lgr);
} else {
conn->rmb_desc->used = 0;
memset(conn->rmb_desc->cpu_addr, 0,
conn->rmb_desc->len +
sizeof(struct smcd_cdc_msg));
}
}
}
/* remove a finished connection from its link group */
void smc_conn_free(struct smc_connection *conn)
{
struct smc_link_group *lgr = conn->lgr;
if (!lgr || conn->freed)
/* Connection has never been registered in a
* link group, or has already been freed.
*/
return;
conn->freed = 1;
if (!smc_conn_lgr_valid(conn))
/* Connection has already unregistered from
* link group.
*/
goto lgr_put;
if (lgr->is_smcd) {
if (!list_empty(&lgr->list))
smc_ism_unset_conn(conn);
tasklet_kill(&conn->rx_tsklet);
} else {
smc_cdc_wait_pend_tx_wr(conn);
if (current_work() != &conn->abort_work)
cancel_work_sync(&conn->abort_work);
}
if (!list_empty(&lgr->list)) {
smc_buf_unuse(conn, lgr); /* allow buffer reuse */
smc_lgr_unregister_conn(conn);
}
if (!lgr->conns_num)
smc_lgr_schedule_free_work(lgr);
lgr_put:
if (!lgr->is_smcd)
smcr_link_put(conn->lnk); /* link_hold in smc_conn_create() */
smc_lgr_put(lgr); /* lgr_hold in smc_conn_create() */
}
/* unregister a link from a buf_desc */
static void smcr_buf_unmap_link(struct smc_buf_desc *buf_desc, bool is_rmb,
struct smc_link *lnk)
{
if (is_rmb || buf_desc->is_vm)
buf_desc->is_reg_mr[lnk->link_idx] = false;
if (!buf_desc->is_map_ib[lnk->link_idx])
return;
if ((is_rmb || buf_desc->is_vm) &&
buf_desc->mr[lnk->link_idx]) {
smc_ib_put_memory_region(buf_desc->mr[lnk->link_idx]);
buf_desc->mr[lnk->link_idx] = NULL;
}
if (is_rmb)
smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_FROM_DEVICE);
else
smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_TO_DEVICE);
sg_free_table(&buf_desc->sgt[lnk->link_idx]);
buf_desc->is_map_ib[lnk->link_idx] = false;
}
/* unmap all buffers of lgr for a deleted link */
static void smcr_buf_unmap_lgr(struct smc_link *lnk)
{
struct smc_link_group *lgr = lnk->lgr;
struct smc_buf_desc *buf_desc, *bf;
int i;
for (i = 0; i < SMC_RMBE_SIZES; i++) {
down_write(&lgr->rmbs_lock);
list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list)
smcr_buf_unmap_link(buf_desc, true, lnk);
up_write(&lgr->rmbs_lock);
down_write(&lgr->sndbufs_lock);
list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i],
list)
smcr_buf_unmap_link(buf_desc, false, lnk);
up_write(&lgr->sndbufs_lock);
}
}
static void smcr_rtoken_clear_link(struct smc_link *lnk)
{
struct smc_link_group *lgr = lnk->lgr;
int i;
for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
lgr->rtokens[i][lnk->link_idx].rkey = 0;
lgr->rtokens[i][lnk->link_idx].dma_addr = 0;
}
}
static void __smcr_link_clear(struct smc_link *lnk)
{
struct smc_link_group *lgr = lnk->lgr;
struct smc_ib_device *smcibdev;
smc_wr_free_link_mem(lnk);
smc_ibdev_cnt_dec(lnk);
put_device(&lnk->smcibdev->ibdev->dev);
smcibdev = lnk->smcibdev;
memset(lnk, 0, sizeof(struct smc_link));
lnk->state = SMC_LNK_UNUSED;
if (!atomic_dec_return(&smcibdev->lnk_cnt))
wake_up(&smcibdev->lnks_deleted);
smc_lgr_put(lgr); /* lgr_hold in smcr_link_init() */
}
/* must be called under lgr->llc_conf_mutex lock */
void smcr_link_clear(struct smc_link *lnk, bool log)
{
if (!lnk->lgr || lnk->clearing ||
lnk->state == SMC_LNK_UNUSED)
return;
lnk->clearing = 1;
lnk->peer_qpn = 0;
smc_llc_link_clear(lnk, log);
smcr_buf_unmap_lgr(lnk);
smcr_rtoken_clear_link(lnk);
smc_ib_modify_qp_error(lnk);
smc_wr_free_link(lnk);
smc_ib_destroy_queue_pair(lnk);
smc_ib_dealloc_protection_domain(lnk);
smcr_link_put(lnk); /* theoretically last link_put */
}
void smcr_link_hold(struct smc_link *lnk)
{
refcount_inc(&lnk->refcnt);
}
void smcr_link_put(struct smc_link *lnk)
{
if (refcount_dec_and_test(&lnk->refcnt))
__smcr_link_clear(lnk);
}
static void smcr_buf_free(struct smc_link_group *lgr, bool is_rmb,
struct smc_buf_desc *buf_desc)
{
int i;
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
smcr_buf_unmap_link(buf_desc, is_rmb, &lgr->lnk[i]);
if (!buf_desc->is_vm && buf_desc->pages)
__free_pages(buf_desc->pages, buf_desc->order);
else if (buf_desc->is_vm && buf_desc->cpu_addr)
vfree(buf_desc->cpu_addr);
kfree(buf_desc);
}
static void smcd_buf_free(struct smc_link_group *lgr, bool is_dmb,
struct smc_buf_desc *buf_desc)
{
if (is_dmb) {
/* restore original buf len */
buf_desc->len += sizeof(struct smcd_cdc_msg);
smc_ism_unregister_dmb(lgr->smcd, buf_desc);
} else {
kfree(buf_desc->cpu_addr);
}
kfree(buf_desc);
}
static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
struct smc_buf_desc *buf_desc)
{
if (lgr->is_smcd)
smcd_buf_free(lgr, is_rmb, buf_desc);
else
smcr_buf_free(lgr, is_rmb, buf_desc);
}
static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb)
{
struct smc_buf_desc *buf_desc, *bf_desc;
struct list_head *buf_list;
int i;
for (i = 0; i < SMC_RMBE_SIZES; i++) {
if (is_rmb)
buf_list = &lgr->rmbs[i];
else
buf_list = &lgr->sndbufs[i];
list_for_each_entry_safe(buf_desc, bf_desc, buf_list,
list) {
list_del(&buf_desc->list);
smc_buf_free(lgr, is_rmb, buf_desc);
}
}
}
static void smc_lgr_free_bufs(struct smc_link_group *lgr)
{
/* free send buffers */
__smc_lgr_free_bufs(lgr, false);
/* free rmbs */
__smc_lgr_free_bufs(lgr, true);
}
/* won't be freed until no one accesses to lgr anymore */
static void __smc_lgr_free(struct smc_link_group *lgr)
{
smc_lgr_free_bufs(lgr);
if (lgr->is_smcd) {
if (!atomic_dec_return(&lgr->smcd->lgr_cnt))
wake_up(&lgr->smcd->lgrs_deleted);
} else {
smc_wr_free_lgr_mem(lgr);
if (!atomic_dec_return(&lgr_cnt))
wake_up(&lgrs_deleted);
}
kfree(lgr);
}
/* remove a link group */
static void smc_lgr_free(struct smc_link_group *lgr)
{
int i;
if (!lgr->is_smcd) {
down_write(&lgr->llc_conf_mutex);
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
if (lgr->lnk[i].state != SMC_LNK_UNUSED)
smcr_link_clear(&lgr->lnk[i], false);
}
up_write(&lgr->llc_conf_mutex);
smc_llc_lgr_clear(lgr);
}
destroy_workqueue(lgr->tx_wq);
if (lgr->is_smcd) {
smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
put_device(lgr->smcd->ops->get_dev(lgr->smcd));
}
smc_lgr_put(lgr); /* theoretically last lgr_put */
}
void smc_lgr_hold(struct smc_link_group *lgr)
{
refcount_inc(&lgr->refcnt);
}
void smc_lgr_put(struct smc_link_group *lgr)
{
if (refcount_dec_and_test(&lgr->refcnt))
__smc_lgr_free(lgr);
}
static void smc_sk_wake_ups(struct smc_sock *smc)
{
smc->sk.sk_write_space(&smc->sk);
smc->sk.sk_data_ready(&smc->sk);
smc->sk.sk_state_change(&smc->sk);
}
/* kill a connection */
static void smc_conn_kill(struct smc_connection *conn, bool soft)
{
struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
if (conn->lgr->is_smcd && conn->lgr->peer_shutdown)
conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
else
smc_close_abort(conn);
conn->killed = 1;
smc->sk.sk_err = ECONNABORTED;
smc_sk_wake_ups(smc);
if (conn->lgr->is_smcd) {
smc_ism_unset_conn(conn);
if (soft)
tasklet_kill(&conn->rx_tsklet);
else
tasklet_unlock_wait(&conn->rx_tsklet);
} else {
smc_cdc_wait_pend_tx_wr(conn);
}
smc_lgr_unregister_conn(conn);
smc_close_active_abort(smc);
}
static void smc_lgr_cleanup(struct smc_link_group *lgr)
{
if (lgr->is_smcd) {
smc_ism_signal_shutdown(lgr);
} else {
u32 rsn = lgr->llc_termination_rsn;
if (!rsn)
rsn = SMC_LLC_DEL_PROG_INIT_TERM;
smc_llc_send_link_delete_all(lgr, false, rsn);
smcr_lgr_link_deactivate_all(lgr);
}
}
/* terminate link group
* @soft: true if link group shutdown can take its time
* false if immediate link group shutdown is required
*/
static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft)
{
struct smc_connection *conn;
struct smc_sock *smc;
struct rb_node *node;
if (lgr->terminating)
return; /* lgr already terminating */
/* cancel free_work sync, will terminate when lgr->freeing is set */
cancel_delayed_work_sync(&lgr->free_work);
lgr->terminating = 1;
/* kill remaining link group connections */
read_lock_bh(&lgr->conns_lock);
node = rb_first(&lgr->conns_all);
while (node) {
read_unlock_bh(&lgr->conns_lock);
conn = rb_entry(node, struct smc_connection, alert_node);
smc = container_of(conn, struct smc_sock, conn);
sock_hold(&smc->sk); /* sock_put below */
lock_sock(&smc->sk);
smc_conn_kill(conn, soft);
release_sock(&smc->sk);
sock_put(&smc->sk); /* sock_hold above */
read_lock_bh(&lgr->conns_lock);
node = rb_first(&lgr->conns_all);
}
read_unlock_bh(&lgr->conns_lock);
smc_lgr_cleanup(lgr);
smc_lgr_free(lgr);
}
/* unlink link group and schedule termination */
void smc_lgr_terminate_sched(struct smc_link_group *lgr)
{
spinlock_t *lgr_lock;
smc_lgr_list_head(lgr, &lgr_lock);
spin_lock_bh(lgr_lock);
if (list_empty(&lgr->list) || lgr->terminating || lgr->freeing) {
spin_unlock_bh(lgr_lock);
return; /* lgr already terminating */
}
list_del_init(&lgr->list);
lgr->freeing = 1;
spin_unlock_bh(lgr_lock);
schedule_work(&lgr->terminate_work);
}
/* Called when peer lgr shutdown (regularly or abnormally) is received */
void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan)
{
struct smc_link_group *lgr, *l;
LIST_HEAD(lgr_free_list);
/* run common cleanup function and build free list */
spin_lock_bh(&dev->lgr_lock);
list_for_each_entry_safe(lgr, l, &dev->lgr_list, list) {
if ((!peer_gid || lgr->peer_gid == peer_gid) &&
(vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
if (peer_gid) /* peer triggered termination */
lgr->peer_shutdown = 1;
list_move(&lgr->list, &lgr_free_list);
lgr->freeing = 1;
}
}
spin_unlock_bh(&dev->lgr_lock);
/* cancel the regular free workers and actually free lgrs */
list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
list_del_init(&lgr->list);
schedule_work(&lgr->terminate_work);
}
}
/* Called when an SMCD device is removed or the smc module is unloaded */
void smc_smcd_terminate_all(struct smcd_dev *smcd)
{
struct smc_link_group *lgr, *lg;
LIST_HEAD(lgr_free_list);
spin_lock_bh(&smcd->lgr_lock);
list_splice_init(&smcd->lgr_list, &lgr_free_list);
list_for_each_entry(lgr, &lgr_free_list, list)
lgr->freeing = 1;
spin_unlock_bh(&smcd->lgr_lock);
list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
list_del_init(&lgr->list);
__smc_lgr_terminate(lgr, false);
}
if (atomic_read(&smcd->lgr_cnt))
wait_event(smcd->lgrs_deleted, !atomic_read(&smcd->lgr_cnt));
}
/* Called when an SMCR device is removed or the smc module is unloaded.
* If smcibdev is given, all SMCR link groups using this device are terminated.
* If smcibdev is NULL, all SMCR link groups are terminated.
*/
void smc_smcr_terminate_all(struct smc_ib_device *smcibdev)
{
struct smc_link_group *lgr, *lg;
LIST_HEAD(lgr_free_list);
int i;
spin_lock_bh(&smc_lgr_list.lock);
if (!smcibdev) {
list_splice_init(&smc_lgr_list.list, &lgr_free_list);
list_for_each_entry(lgr, &lgr_free_list, list)
lgr->freeing = 1;
} else {
list_for_each_entry_safe(lgr, lg, &smc_lgr_list.list, list) {
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
if (lgr->lnk[i].smcibdev == smcibdev)
smcr_link_down_cond_sched(&lgr->lnk[i]);
}
}
}
spin_unlock_bh(&smc_lgr_list.lock);
list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
list_del_init(&lgr->list);
smc_llc_set_termination_rsn(lgr, SMC_LLC_DEL_OP_INIT_TERM);
__smc_lgr_terminate(lgr, false);
}
if (smcibdev) {
if (atomic_read(&smcibdev->lnk_cnt))
wait_event(smcibdev->lnks_deleted,
!atomic_read(&smcibdev->lnk_cnt));
} else {
if (atomic_read(&lgr_cnt))
wait_event(lgrs_deleted, !atomic_read(&lgr_cnt));
}
}
/* set new lgr type and clear all asymmetric link tagging */
void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type)
{
char *lgr_type = "";
int i;
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
if (smc_link_usable(&lgr->lnk[i]))
lgr->lnk[i].link_is_asym = false;
if (lgr->type == new_type)
return;
lgr->type = new_type;
switch (lgr->type) {
case SMC_LGR_NONE:
lgr_type = "NONE";
break;
case SMC_LGR_SINGLE:
lgr_type = "SINGLE";
break;
case SMC_LGR_SYMMETRIC:
lgr_type = "SYMMETRIC";
break;
case SMC_LGR_ASYMMETRIC_PEER:
lgr_type = "ASYMMETRIC_PEER";
break;
case SMC_LGR_ASYMMETRIC_LOCAL:
lgr_type = "ASYMMETRIC_LOCAL";
break;
}
pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu state changed: "
"%s, pnetid %.16s\n", SMC_LGR_ID_SIZE, &lgr->id,
lgr->net->net_cookie, lgr_type, lgr->pnet_id);
}
/* set new lgr type and tag a link as asymmetric */
void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
enum smc_lgr_type new_type, int asym_lnk_idx)
{
smcr_lgr_set_type(lgr, new_type);
lgr->lnk[asym_lnk_idx].link_is_asym = true;
}
/* abort connection, abort_work scheduled from tasklet context */
static void smc_conn_abort_work(struct work_struct *work)
{
struct smc_connection *conn = container_of(work,
struct smc_connection,
abort_work);
struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
lock_sock(&smc->sk);
smc_conn_kill(conn, true);
release_sock(&smc->sk);
sock_put(&smc->sk); /* sock_hold done by schedulers of abort_work */
}
void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport)
{
struct smc_link_group *lgr, *n;
list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
struct smc_link *link;
if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
SMC_MAX_PNETID_LEN) ||
lgr->type == SMC_LGR_SYMMETRIC ||
lgr->type == SMC_LGR_ASYMMETRIC_PEER ||
!rdma_dev_access_netns(smcibdev->ibdev, lgr->net))
continue;
/* trigger local add link processing */
link = smc_llc_usable_link(lgr);
if (link)
smc_llc_add_link_local(link);
}
}
/* link is down - switch connections to alternate link,
* must be called under lgr->llc_conf_mutex lock
*/
static void smcr_link_down(struct smc_link *lnk)
{
struct smc_link_group *lgr = lnk->lgr;
struct smc_link *to_lnk;
int del_link_id;
if (!lgr || lnk->state == SMC_LNK_UNUSED || list_empty(&lgr->list))
return;
to_lnk = smc_switch_conns(lgr, lnk, true);
if (!to_lnk) { /* no backup link available */
smcr_link_clear(lnk, true);
return;
}
smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
del_link_id = lnk->link_id;
if (lgr->role == SMC_SERV) {
/* trigger local delete link processing */
smc_llc_srv_delete_link_local(to_lnk, del_link_id);
} else {
if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
/* another llc task is ongoing */
up_write(&lgr->llc_conf_mutex);
wait_event_timeout(lgr->llc_flow_waiter,
(list_empty(&lgr->list) ||
lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE),
SMC_LLC_WAIT_TIME);
down_write(&lgr->llc_conf_mutex);
}
if (!list_empty(&lgr->list)) {
smc_llc_send_delete_link(to_lnk, del_link_id,
SMC_LLC_REQ, true,
SMC_LLC_DEL_LOST_PATH);
smcr_link_clear(lnk, true);
}
wake_up(&lgr->llc_flow_waiter); /* wake up next waiter */
}
}
/* must be called under lgr->llc_conf_mutex lock */
void smcr_link_down_cond(struct smc_link *lnk)
{
if (smc_link_downing(&lnk->state)) {
trace_smcr_link_down(lnk, __builtin_return_address(0));
smcr_link_down(lnk);
}
}
/* will get the lgr->llc_conf_mutex lock */
void smcr_link_down_cond_sched(struct smc_link *lnk)
{
if (smc_link_downing(&lnk->state)) {
trace_smcr_link_down(lnk, __builtin_return_address(0));
schedule_work(&lnk->link_down_wrk);
}
}
void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport)
{
struct smc_link_group *lgr, *n;
int i;
list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
SMC_MAX_PNETID_LEN))
continue; /* lgr is not affected */
if (list_empty(&lgr->list))
continue;
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
struct smc_link *lnk = &lgr->lnk[i];
if (smc_link_usable(lnk) &&
lnk->smcibdev == smcibdev && lnk->ibport == ibport)
smcr_link_down_cond_sched(lnk);
}
}
}
static void smc_link_down_work(struct work_struct *work)
{
struct smc_link *link = container_of(work, struct smc_link,
link_down_wrk);
struct smc_link_group *lgr = link->lgr;
if (list_empty(&lgr->list))
return;
wake_up_all(&lgr->llc_msg_waiter);
down_write(&lgr->llc_conf_mutex);
smcr_link_down(link);
up_write(&lgr->llc_conf_mutex);
}
static int smc_vlan_by_tcpsk_walk(struct net_device *lower_dev,
struct netdev_nested_priv *priv)
{
unsigned short *vlan_id = (unsigned short *)priv->data;
if (is_vlan_dev(lower_dev)) {
*vlan_id = vlan_dev_vlan_id(lower_dev);
return 1;
}
return 0;
}
/* Determine vlan of internal TCP socket. */
int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini)
{
struct dst_entry *dst = sk_dst_get(clcsock->sk);
struct netdev_nested_priv priv;
struct net_device *ndev;
int rc = 0;
ini->vlan_id = 0;
if (!dst) {
rc = -ENOTCONN;
goto out;
}
if (!dst->dev) {
rc = -ENODEV;
goto out_rel;
}
ndev = dst->dev;
if (is_vlan_dev(ndev)) {
ini->vlan_id = vlan_dev_vlan_id(ndev);
goto out_rel;
}
priv.data = (void *)&ini->vlan_id;
rtnl_lock();
netdev_walk_all_lower_dev(ndev, smc_vlan_by_tcpsk_walk, &priv);
rtnl_unlock();
out_rel:
dst_release(dst);
out:
return rc;
}
static bool smcr_lgr_match(struct smc_link_group *lgr, u8 smcr_version,
u8 peer_systemid[],
u8 peer_gid[],
u8 peer_mac_v1[],
enum smc_lgr_role role, u32 clcqpn,
struct net *net)
{
struct smc_link *lnk;
int i;
if (memcmp(lgr->peer_systemid, peer_systemid, SMC_SYSTEMID_LEN) ||
lgr->role != role)
return false;
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
lnk = &lgr->lnk[i];
if (!smc_link_active(lnk))
continue;
/* use verbs API to check netns, instead of lgr->net */
if (!rdma_dev_access_netns(lnk->smcibdev->ibdev, net))
return false;
if ((lgr->role == SMC_SERV || lnk->peer_qpn == clcqpn) &&
!memcmp(lnk->peer_gid, peer_gid, SMC_GID_SIZE) &&
(smcr_version == SMC_V2 ||
!memcmp(lnk->peer_mac, peer_mac_v1, ETH_ALEN)))
return true;
}
return false;
}
static bool smcd_lgr_match(struct smc_link_group *lgr,
struct smcd_dev *smcismdev, u64 peer_gid)
{
return lgr->peer_gid == peer_gid && lgr->smcd == smcismdev;
}
/* create a new SMC connection (and a new link group if necessary) */
int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini)
{
struct smc_connection *conn = &smc->conn;
struct net *net = sock_net(&smc->sk);
struct list_head *lgr_list;
struct smc_link_group *lgr;
enum smc_lgr_role role;
spinlock_t *lgr_lock;
int rc = 0;
lgr_list = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_list :
&smc_lgr_list.list;
lgr_lock = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_lock :
&smc_lgr_list.lock;
ini->first_contact_local = 1;
role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
if (role == SMC_CLNT && ini->first_contact_peer)
/* create new link group as well */
goto create;
/* determine if an existing link group can be reused */
spin_lock_bh(lgr_lock);
list_for_each_entry(lgr, lgr_list, list) {
write_lock_bh(&lgr->conns_lock);
if ((ini->is_smcd ?
smcd_lgr_match(lgr, ini->ism_dev[ini->ism_selected],
ini->ism_peer_gid[ini->ism_selected]) :
smcr_lgr_match(lgr, ini->smcr_version,
ini->peer_systemid,
ini->peer_gid, ini->peer_mac, role,
ini->ib_clcqpn, net)) &&
!lgr->sync_err &&
(ini->smcd_version == SMC_V2 ||
lgr->vlan_id == ini->vlan_id) &&
(role == SMC_CLNT || ini->is_smcd ||
(lgr->conns_num < SMC_RMBS_PER_LGR_MAX &&
!bitmap_full(lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX)))) {
/* link group found */
ini->first_contact_local = 0;
conn->lgr = lgr;
rc = smc_lgr_register_conn(conn, false);
write_unlock_bh(&lgr->conns_lock);
if (!rc && delayed_work_pending(&lgr->free_work))
cancel_delayed_work(&lgr->free_work);
break;
}
write_unlock_bh(&lgr->conns_lock);
}
spin_unlock_bh(lgr_lock);
if (rc)
return rc;
if (role == SMC_CLNT && !ini->first_contact_peer &&
ini->first_contact_local) {
/* Server reuses a link group, but Client wants to start
* a new one
* send out_of_sync decline, reason synchr. error
*/
return SMC_CLC_DECL_SYNCERR;
}
create:
if (ini->first_contact_local) {
rc = smc_lgr_create(smc, ini);
if (rc)
goto out;
lgr = conn->lgr;
write_lock_bh(&lgr->conns_lock);
rc = smc_lgr_register_conn(conn, true);
write_unlock_bh(&lgr->conns_lock);
if (rc) {
smc_lgr_cleanup_early(lgr);
goto out;
}
}
smc_lgr_hold(conn->lgr); /* lgr_put in smc_conn_free() */
if (!conn->lgr->is_smcd)
smcr_link_hold(conn->lnk); /* link_put in smc_conn_free() */
conn->freed = 0;
conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE;
conn->local_tx_ctrl.len = SMC_WR_TX_SIZE;
conn->urg_state = SMC_URG_READ;
init_waitqueue_head(&conn->cdc_pend_tx_wq);
INIT_WORK(&smc->conn.abort_work, smc_conn_abort_work);
if (ini->is_smcd) {
conn->rx_off = sizeof(struct smcd_cdc_msg);
smcd_cdc_rx_init(conn); /* init tasklet for this conn */
} else {
conn->rx_off = 0;
}
#ifndef KERNEL_HAS_ATOMIC64
spin_lock_init(&conn->acurs_lock);
#endif
out:
return rc;
}
#define SMCD_DMBE_SIZES 6 /* 0 -> 16KB, 1 -> 32KB, .. 6 -> 1MB */
#define SMCR_RMBE_SIZES 5 /* 0 -> 16KB, 1 -> 32KB, .. 5 -> 512KB */
/* convert the RMB size into the compressed notation (minimum 16K, see
* SMCD/R_DMBE_SIZES.
* In contrast to plain ilog2, this rounds towards the next power of 2,
* so the socket application gets at least its desired sndbuf / rcvbuf size.
*/
static u8 smc_compress_bufsize(int size, bool is_smcd, bool is_rmb)
{
const unsigned int max_scat = SG_MAX_SINGLE_ALLOC * PAGE_SIZE;
u8 compressed;
if (size <= SMC_BUF_MIN_SIZE)
return 0;
size = (size - 1) >> 14; /* convert to 16K multiple */
compressed = min_t(u8, ilog2(size) + 1,
is_smcd ? SMCD_DMBE_SIZES : SMCR_RMBE_SIZES);
if (!is_smcd && is_rmb)
/* RMBs are backed by & limited to max size of scatterlists */
compressed = min_t(u8, compressed, ilog2(max_scat >> 14));
return compressed;
}
/* convert the RMB size from compressed notation into integer */
int smc_uncompress_bufsize(u8 compressed)
{
u32 size;
size = 0x00000001 << (((int)compressed) + 14);
return (int)size;
}
/* try to reuse a sndbuf or rmb description slot for a certain
* buffer size; if not available, return NULL
*/
static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize,
struct rw_semaphore *lock,
struct list_head *buf_list)
{
struct smc_buf_desc *buf_slot;
down_read(lock);
list_for_each_entry(buf_slot, buf_list, list) {
if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
up_read(lock);
return buf_slot;
}
}
up_read(lock);
return NULL;
}
/* one of the conditions for announcing a receiver's current window size is
* that it "results in a minimum increase in the window size of 10% of the
* receive buffer space" [RFC7609]
*/
static inline int smc_rmb_wnd_update_limit(int rmbe_size)
{
return max_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
}
/* map an buf to a link */
static int smcr_buf_map_link(struct smc_buf_desc *buf_desc, bool is_rmb,
struct smc_link *lnk)
{
int rc, i, nents, offset, buf_size, size, access_flags;
struct scatterlist *sg;
void *buf;
if (buf_desc->is_map_ib[lnk->link_idx])
return 0;
if (buf_desc->is_vm) {
buf = buf_desc->cpu_addr;
buf_size = buf_desc->len;
offset = offset_in_page(buf_desc->cpu_addr);
nents = PAGE_ALIGN(buf_size + offset) / PAGE_SIZE;
} else {
nents = 1;
}
rc = sg_alloc_table(&buf_desc->sgt[lnk->link_idx], nents, GFP_KERNEL);
if (rc)
return rc;
if (buf_desc->is_vm) {
/* virtually contiguous buffer */
for_each_sg(buf_desc->sgt[lnk->link_idx].sgl, sg, nents, i) {
size = min_t(int, PAGE_SIZE - offset, buf_size);
sg_set_page(sg, vmalloc_to_page(buf), size, offset);
buf += size / sizeof(*buf);
buf_size -= size;
offset = 0;
}
} else {
/* physically contiguous buffer */
sg_set_buf(buf_desc->sgt[lnk->link_idx].sgl,
buf_desc->cpu_addr, buf_desc->len);
}
/* map sg table to DMA address */
rc = smc_ib_buf_map_sg(lnk, buf_desc,
is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
/* SMC protocol depends on mapping to one DMA address only */
if (rc != nents) {
rc = -EAGAIN;
goto free_table;
}
buf_desc->is_dma_need_sync |=
smc_ib_is_sg_need_sync(lnk, buf_desc) << lnk->link_idx;
if (is_rmb || buf_desc->is_vm) {
/* create a new memory region for the RMB or vzalloced sndbuf */
access_flags = is_rmb ?
IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
IB_ACCESS_LOCAL_WRITE;
rc = smc_ib_get_memory_region(lnk->roce_pd, access_flags,
buf_desc, lnk->link_idx);
if (rc)
goto buf_unmap;
smc_ib_sync_sg_for_device(lnk, buf_desc,
is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
}
buf_desc->is_map_ib[lnk->link_idx] = true;
return 0;
buf_unmap:
smc_ib_buf_unmap_sg(lnk, buf_desc,
is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
free_table:
sg_free_table(&buf_desc->sgt[lnk->link_idx]);
return rc;
}
/* register a new buf on IB device, rmb or vzalloced sndbuf
* must be called under lgr->llc_conf_mutex lock
*/
int smcr_link_reg_buf(struct smc_link *link, struct smc_buf_desc *buf_desc)
{
if (list_empty(&link->lgr->list))
return -ENOLINK;
if (!buf_desc->is_reg_mr[link->link_idx]) {
/* register memory region for new buf */
if (buf_desc->is_vm)
buf_desc->mr[link->link_idx]->iova =
(uintptr_t)buf_desc->cpu_addr;
if (smc_wr_reg_send(link, buf_desc->mr[link->link_idx])) {
buf_desc->is_reg_err = true;
return -EFAULT;
}
buf_desc->is_reg_mr[link->link_idx] = true;
}
return 0;
}
static int _smcr_buf_map_lgr(struct smc_link *lnk, struct rw_semaphore *lock,
struct list_head *lst, bool is_rmb)
{
struct smc_buf_desc *buf_desc, *bf;
int rc = 0;
down_write(lock);
list_for_each_entry_safe(buf_desc, bf, lst, list) {
if (!buf_desc->used)
continue;
rc = smcr_buf_map_link(buf_desc, is_rmb, lnk);
if (rc)
goto out;
}
out:
up_write(lock);
return rc;
}
/* map all used buffers of lgr for a new link */
int smcr_buf_map_lgr(struct smc_link *lnk)
{
struct smc_link_group *lgr = lnk->lgr;
int i, rc = 0;
for (i = 0; i < SMC_RMBE_SIZES; i++) {
rc = _smcr_buf_map_lgr(lnk, &lgr->rmbs_lock,
&lgr->rmbs[i], true);
if (rc)
return rc;
rc = _smcr_buf_map_lgr(lnk, &lgr->sndbufs_lock,
&lgr->sndbufs[i], false);
if (rc)
return rc;
}
return 0;
}
/* register all used buffers of lgr for a new link,
* must be called under lgr->llc_conf_mutex lock
*/
int smcr_buf_reg_lgr(struct smc_link *lnk)
{
struct smc_link_group *lgr = lnk->lgr;
struct smc_buf_desc *buf_desc, *bf;
int i, rc = 0;
/* reg all RMBs for a new link */
down_write(&lgr->rmbs_lock);
for (i = 0; i < SMC_RMBE_SIZES; i++) {
list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list) {
if (!buf_desc->used)
continue;
rc = smcr_link_reg_buf(lnk, buf_desc);
if (rc) {
up_write(&lgr->rmbs_lock);
return rc;
}
}
}
up_write(&lgr->rmbs_lock);
if (lgr->buf_type == SMCR_PHYS_CONT_BUFS)
return rc;
/* reg all vzalloced sndbufs for a new link */
down_write(&lgr->sndbufs_lock);
for (i = 0; i < SMC_RMBE_SIZES; i++) {
list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i], list) {
if (!buf_desc->used || !buf_desc->is_vm)
continue;
rc = smcr_link_reg_buf(lnk, buf_desc);
if (rc) {
up_write(&lgr->sndbufs_lock);
return rc;
}
}
}
up_write(&lgr->sndbufs_lock);
return rc;
}
static struct smc_buf_desc *smcr_new_buf_create(struct smc_link_group *lgr,
bool is_rmb, int bufsize)
{
struct smc_buf_desc *buf_desc;
/* try to alloc a new buffer */
buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
if (!buf_desc)
return ERR_PTR(-ENOMEM);
switch (lgr->buf_type) {
case SMCR_PHYS_CONT_BUFS:
case SMCR_MIXED_BUFS:
buf_desc->order = get_order(bufsize);
buf_desc->pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN |
__GFP_NOMEMALLOC | __GFP_COMP |
__GFP_NORETRY | __GFP_ZERO,
buf_desc->order);
if (buf_desc->pages) {
buf_desc->cpu_addr =
(void *)page_address(buf_desc->pages);
buf_desc->len = bufsize;
buf_desc->is_vm = false;
break;
}
if (lgr->buf_type == SMCR_PHYS_CONT_BUFS)
goto out;
fallthrough; // try virtually continguous buf
case SMCR_VIRT_CONT_BUFS:
buf_desc->order = get_order(bufsize);
buf_desc->cpu_addr = vzalloc(PAGE_SIZE << buf_desc->order);
if (!buf_desc->cpu_addr)
goto out;
buf_desc->pages = NULL;
buf_desc->len = bufsize;
buf_desc->is_vm = true;
break;
}
return buf_desc;
out:
kfree(buf_desc);
return ERR_PTR(-EAGAIN);
}
/* map buf_desc on all usable links,
* unused buffers stay mapped as long as the link is up
*/
static int smcr_buf_map_usable_links(struct smc_link_group *lgr,
struct smc_buf_desc *buf_desc, bool is_rmb)
{
int i, rc = 0, cnt = 0;
/* protect against parallel link reconfiguration */
down_read(&lgr->llc_conf_mutex);
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
struct smc_link *lnk = &lgr->lnk[i];
if (!smc_link_usable(lnk))
continue;
if (smcr_buf_map_link(buf_desc, is_rmb, lnk)) {
rc = -ENOMEM;
goto out;
}
cnt++;
}
out:
up_read(&lgr->llc_conf_mutex);
if (!rc && !cnt)
rc = -EINVAL;
return rc;
}
static struct smc_buf_desc *smcd_new_buf_create(struct smc_link_group *lgr,
bool is_dmb, int bufsize)
{
struct smc_buf_desc *buf_desc;
int rc;
/* try to alloc a new DMB */
buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
if (!buf_desc)
return ERR_PTR(-ENOMEM);
if (is_dmb) {
rc = smc_ism_register_dmb(lgr, bufsize, buf_desc);
if (rc) {
kfree(buf_desc);
if (rc == -ENOMEM)
return ERR_PTR(-EAGAIN);
if (rc == -ENOSPC)
return ERR_PTR(-ENOSPC);
return ERR_PTR(-EIO);
}
buf_desc->pages = virt_to_page(buf_desc->cpu_addr);
/* CDC header stored in buf. So, pretend it was smaller */
buf_desc->len = bufsize - sizeof(struct smcd_cdc_msg);
} else {
buf_desc->cpu_addr = kzalloc(bufsize, GFP_KERNEL |
__GFP_NOWARN | __GFP_NORETRY |
__GFP_NOMEMALLOC);
if (!buf_desc->cpu_addr) {
kfree(buf_desc);
return ERR_PTR(-EAGAIN);
}
buf_desc->len = bufsize;
}
return buf_desc;
}
static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb)
{
struct smc_buf_desc *buf_desc = ERR_PTR(-ENOMEM);
struct smc_connection *conn = &smc->conn;
struct smc_link_group *lgr = conn->lgr;
struct list_head *buf_list;
int bufsize, bufsize_short;
struct rw_semaphore *lock; /* lock buffer list */
bool is_dgraded = false;
int sk_buf_size;
if (is_rmb)
/* use socket recv buffer size (w/o overhead) as start value */
sk_buf_size = smc->sk.sk_rcvbuf;
else
/* use socket send buffer size (w/o overhead) as start value */
sk_buf_size = smc->sk.sk_sndbuf;
for (bufsize_short = smc_compress_bufsize(sk_buf_size, is_smcd, is_rmb);
bufsize_short >= 0; bufsize_short--) {
if (is_rmb) {
lock = &lgr->rmbs_lock;
buf_list = &lgr->rmbs[bufsize_short];
} else {
lock = &lgr->sndbufs_lock;
buf_list = &lgr->sndbufs[bufsize_short];
}
bufsize = smc_uncompress_bufsize(bufsize_short);
/* check for reusable slot in the link group */
buf_desc = smc_buf_get_slot(bufsize_short, lock, buf_list);
if (buf_desc) {
buf_desc->is_dma_need_sync = 0;
SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
SMC_STAT_BUF_REUSE(smc, is_smcd, is_rmb);
break; /* found reusable slot */
}
if (is_smcd)
buf_desc = smcd_new_buf_create(lgr, is_rmb, bufsize);
else
buf_desc = smcr_new_buf_create(lgr, is_rmb, bufsize);
if (PTR_ERR(buf_desc) == -ENOMEM)
break;
if (IS_ERR(buf_desc)) {
if (!is_dgraded) {
is_dgraded = true;
SMC_STAT_RMB_DOWNGRADED(smc, is_smcd, is_rmb);
}
continue;
}
SMC_STAT_RMB_ALLOC(smc, is_smcd, is_rmb);
SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
buf_desc->used = 1;
down_write(lock);
list_add(&buf_desc->list, buf_list);
up_write(lock);
break; /* found */
}
if (IS_ERR(buf_desc))
return PTR_ERR(buf_desc);
if (!is_smcd) {
if (smcr_buf_map_usable_links(lgr, buf_desc, is_rmb)) {
smcr_buf_unuse(buf_desc, is_rmb, lgr);
return -ENOMEM;
}
}
if (is_rmb) {
conn->rmb_desc = buf_desc;
conn->rmbe_size_short = bufsize_short;
smc->sk.sk_rcvbuf = bufsize;
atomic_set(&conn->bytes_to_rcv, 0);
conn->rmbe_update_limit =
smc_rmb_wnd_update_limit(buf_desc->len);
if (is_smcd)
smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */
} else {
conn->sndbuf_desc = buf_desc;
smc->sk.sk_sndbuf = bufsize;
atomic_set(&conn->sndbuf_space, bufsize);
}
return 0;
}
void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn)
{
if (!conn->sndbuf_desc->is_dma_need_sync)
return;
if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd ||
!smc_link_active(conn->lnk))
return;
smc_ib_sync_sg_for_device(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
}
void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn)
{
int i;
if (!conn->rmb_desc->is_dma_need_sync)
return;
if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd)
return;
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
if (!smc_link_active(&conn->lgr->lnk[i]))
continue;
smc_ib_sync_sg_for_cpu(&conn->lgr->lnk[i], conn->rmb_desc,
DMA_FROM_DEVICE);
}
}
/* create the send and receive buffer for an SMC socket;
* receive buffers are called RMBs;
* (even though the SMC protocol allows more than one RMB-element per RMB,
* the Linux implementation uses just one RMB-element per RMB, i.e. uses an
* extra RMB for every connection in a link group
*/
int smc_buf_create(struct smc_sock *smc, bool is_smcd)
{
int rc;
/* create send buffer */
rc = __smc_buf_create(smc, is_smcd, false);
if (rc)
return rc;
/* create rmb */
rc = __smc_buf_create(smc, is_smcd, true);
if (rc) {
down_write(&smc->conn.lgr->sndbufs_lock);
list_del(&smc->conn.sndbuf_desc->list);
up_write(&smc->conn.lgr->sndbufs_lock);
smc_buf_free(smc->conn.lgr, false, smc->conn.sndbuf_desc);
smc->conn.sndbuf_desc = NULL;
}
return rc;
}
static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr)
{
int i;
for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) {
if (!test_and_set_bit(i, lgr->rtokens_used_mask))
return i;
}
return -ENOSPC;
}
static int smc_rtoken_find_by_link(struct smc_link_group *lgr, int lnk_idx,
u32 rkey)
{
int i;
for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
if (test_bit(i, lgr->rtokens_used_mask) &&
lgr->rtokens[i][lnk_idx].rkey == rkey)
return i;
}
return -ENOENT;
}
/* set rtoken for a new link to an existing rmb */
void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
__be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey)
{
int rtok_idx;
rtok_idx = smc_rtoken_find_by_link(lgr, link_idx, ntohl(nw_rkey_known));
if (rtok_idx == -ENOENT)
return;
lgr->rtokens[rtok_idx][link_idx_new].rkey = ntohl(nw_rkey);
lgr->rtokens[rtok_idx][link_idx_new].dma_addr = be64_to_cpu(nw_vaddr);
}
/* set rtoken for a new link whose link_id is given */
void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
__be64 nw_vaddr, __be32 nw_rkey)
{
u64 dma_addr = be64_to_cpu(nw_vaddr);
u32 rkey = ntohl(nw_rkey);
bool found = false;
int link_idx;
for (link_idx = 0; link_idx < SMC_LINKS_PER_LGR_MAX; link_idx++) {
if (lgr->lnk[link_idx].link_id == link_id) {
found = true;
break;
}
}
if (!found)
return;
lgr->rtokens[rtok_idx][link_idx].rkey = rkey;
lgr->rtokens[rtok_idx][link_idx].dma_addr = dma_addr;
}
/* add a new rtoken from peer */
int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey)
{
struct smc_link_group *lgr = smc_get_lgr(lnk);
u64 dma_addr = be64_to_cpu(nw_vaddr);
u32 rkey = ntohl(nw_rkey);
int i;
for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
lgr->rtokens[i][lnk->link_idx].dma_addr == dma_addr &&
test_bit(i, lgr->rtokens_used_mask)) {
/* already in list */
return i;
}
}
i = smc_rmb_reserve_rtoken_idx(lgr);
if (i < 0)
return i;
lgr->rtokens[i][lnk->link_idx].rkey = rkey;
lgr->rtokens[i][lnk->link_idx].dma_addr = dma_addr;
return i;
}
/* delete an rtoken from all links */
int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey)
{
struct smc_link_group *lgr = smc_get_lgr(lnk);
u32 rkey = ntohl(nw_rkey);
int i, j;
for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
test_bit(i, lgr->rtokens_used_mask)) {
for (j = 0; j < SMC_LINKS_PER_LGR_MAX; j++) {
lgr->rtokens[i][j].rkey = 0;
lgr->rtokens[i][j].dma_addr = 0;
}
clear_bit(i, lgr->rtokens_used_mask);
return 0;
}
}
return -ENOENT;
}
/* save rkey and dma_addr received from peer during clc handshake */
int smc_rmb_rtoken_handling(struct smc_connection *conn,
struct smc_link *lnk,
struct smc_clc_msg_accept_confirm *clc)
{
conn->rtoken_idx = smc_rtoken_add(lnk, clc->r0.rmb_dma_addr,
clc->r0.rmb_rkey);
if (conn->rtoken_idx < 0)
return conn->rtoken_idx;
return 0;
}
static void smc_core_going_away(void)
{
struct smc_ib_device *smcibdev;
struct smcd_dev *smcd;
mutex_lock(&smc_ib_devices.mutex);
list_for_each_entry(smcibdev, &smc_ib_devices.list, list) {
int i;
for (i = 0; i < SMC_MAX_PORTS; i++)
set_bit(i, smcibdev->ports_going_away);
}
mutex_unlock(&smc_ib_devices.mutex);
mutex_lock(&smcd_dev_list.mutex);
list_for_each_entry(smcd, &smcd_dev_list.list, list) {
smcd->going_away = 1;
}
mutex_unlock(&smcd_dev_list.mutex);
}
/* Clean up all SMC link groups */
static void smc_lgrs_shutdown(void)
{
struct smcd_dev *smcd;
smc_core_going_away();
smc_smcr_terminate_all(NULL);
mutex_lock(&smcd_dev_list.mutex);
list_for_each_entry(smcd, &smcd_dev_list.list, list)
smc_smcd_terminate_all(smcd);
mutex_unlock(&smcd_dev_list.mutex);
}
static int smc_core_reboot_event(struct notifier_block *this,
unsigned long event, void *ptr)
{
smc_lgrs_shutdown();
smc_ib_unregister_client();
smc_ism_exit();
return 0;
}
static struct notifier_block smc_reboot_notifier = {
.notifier_call = smc_core_reboot_event,
};
int __init smc_core_init(void)
{
return register_reboot_notifier(&smc_reboot_notifier);
}
/* Called (from smc_exit) when module is removed */
void smc_core_exit(void)
{
unregister_reboot_notifier(&smc_reboot_notifier);
smc_lgrs_shutdown();
}
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