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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // 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 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, lgr->smcd->local_gid,
                   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 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 */
     mutex_init(&lgr->sndbufs_lock);
     mutex_init(&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 */
         get_device(&ini->ism_dev[ini->ism_selected]->dev);
         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);
         if (smc_wr_alloc_lgr_mem(lgr))
             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 mutex *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() */
             mutex_lock(&lgr->llc_conf_mutex);
             smc_llc_do_delete_rkey(lgr, buf_desc);
             buf_desc->is_conf_rkey = false;
             mutex_unlock(&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;
         mutex_lock(lock);
         list_del(&buf_desc->list);
         mutex_unlock(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++) {
         mutex_lock(&lgr->rmbs_lock);
         list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list)
             smcr_buf_unmap_link(buf_desc, true, lnk);
         mutex_unlock(&lgr->rmbs_lock);
         mutex_lock(&lgr->sndbufs_lock);
         list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i],
                      list)
             smcr_buf_unmap_link(buf_desc, false, lnk);
         mutex_unlock(&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) {
         mutex_lock(&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);
         }
         mutex_unlock(&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->dev);
     }
     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 */
             mutex_unlock(&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);
             mutex_lock(&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);
     mutex_lock(&lgr->llc_conf_mutex);
     smcr_link_down(link);
     mutex_unlock(&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 mutex *lock,
                          struct list_head *buf_list)
 {
     struct smc_buf_desc *buf_slot;
 
     mutex_lock(lock);
     list_for_each_entry(buf_slot, buf_list, list) {
         if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
             mutex_unlock(lock);
             return buf_slot;
         }
     }
     mutex_unlock(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 mutex *lock,
                  struct list_head *lst, bool is_rmb)
 {
     struct smc_buf_desc *buf_desc, *bf;
     int rc = 0;
 
     mutex_lock(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:
     mutex_unlock(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 */
     mutex_lock(&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) {
                 mutex_unlock(&lgr->rmbs_lock);
                 return rc;
             }
         }
     }
     mutex_unlock(&lgr->rmbs_lock);
 
     if (lgr->buf_type == SMCR_PHYS_CONT_BUFS)
         return rc;
 
     /* reg all vzalloced sndbufs for a new link */
     mutex_lock(&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) {
                 mutex_unlock(&lgr->sndbufs_lock);
                 return rc;
             }
         }
     }
     mutex_unlock(&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 */
     mutex_lock(&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:
     mutex_unlock(&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;
     bool is_dgraded = false;
     struct mutex *lock; /* lock buffer list */
     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 / 2;
     else
         /* use socket send buffer size (w/o overhead) as start value */
         sk_buf_size = smc->sk.sk_sndbuf / 2;
 
     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;
         mutex_lock(lock);
         list_add(&buf_desc->list, buf_list);
         mutex_unlock(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 * 2;
         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 * 2;
         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) {
         mutex_lock(&smc->conn.lgr->sndbufs_lock);
         list_del(&smc->conn.sndbuf_desc->list);
         mutex_unlock(&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();
     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();
 }