net/smc: create improved SMC-R link_uid

The link_uid of an SMC-R link is exchanged between SMC peers and its
value can be used for debugging purposes. Create a unique link_uid
during link initialization and use it in communication with SMC-R peers.

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index fb391bc..fb5f685 100644 (file)
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -331,6 +331,7 @@ int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
        lnk->smcibdev = ini->ib_dev;
        lnk->ibport = ini->ib_port;
        lnk->path_mtu = ini->ib_dev->pattr[ini->ib_port - 1].active_mtu;
+       smc_llc_link_set_uid(lnk);
        INIT_WORK(&lnk->link_down_wrk, smc_link_down_work);
        if (!ini->ib_dev->initialized) {
                rc = (int)smc_ib_setup_per_ibdev(ini->ib_dev);

diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index 32bc45a..e2ace20 100644 (file)
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -70,6 +70,8 @@ struct smc_rdma_wr {                          /* work requests per message
        struct ib_rdma_wr       wr_tx_rdma[SMC_MAX_RDMA_WRITES];
 };
 
+#define SMC_LGR_ID_SIZE                4
+
 struct smc_link {
        struct smc_ib_device    *smcibdev;      /* ib-device */
        u8                      ibport;         /* port - values 1 | 2 */
@@ -116,6 +118,7 @@ struct smc_link {
        u8                      peer_mac[ETH_ALEN];     /* = gid[8:10||13:15] */
        u8                      peer_gid[SMC_GID_SIZE]; /* gid of peer*/
        u8                      link_id;        /* unique # within link group */
+       u8                      link_uid[SMC_LGR_ID_SIZE]; /* unique lnk id */
        u8                      link_idx;       /* index in lgr link array */
        u8                      link_is_asym;   /* is link asymmetric? */
        struct smc_link_group   *lgr;           /* parent link group */
@@ -178,7 +181,6 @@ struct smc_rtoken {                         /* address/key of remote RMB */
        u32                     rkey;
 };
 
-#define SMC_LGR_ID_SIZE                4
 #define SMC_BUF_MIN_SIZE       16384   /* minimum size of an RMB */
 #define SMC_RMBE_SIZES         16      /* number of distinct RMBE sizes */
 /* theoretically, the RFC states that largest size would be 512K,

diff --git a/net/smc/smc_llc.c b/net/smc/smc_llc.c
index 482acf8..afb889d 100644 (file)
--- a/net/smc/smc_llc.c
+++ b/net/smc/smc_llc.c
@@ -361,7 +361,6 @@ static int smc_llc_add_pending_send(struct smc_link *link,
 int smc_llc_send_confirm_link(struct smc_link *link,
                              enum smc_llc_reqresp reqresp)
 {
-       struct smc_link_group *lgr = smc_get_lgr(link);
        struct smc_llc_msg_confirm_link *confllc;
        struct smc_wr_tx_pend_priv *pend;
        struct smc_wr_buf *wr_buf;
@@ -382,7 +381,7 @@ int smc_llc_send_confirm_link(struct smc_link *link,
        memcpy(confllc->sender_gid, link->gid, SMC_GID_SIZE);
        hton24(confllc->sender_qp_num, link->roce_qp->qp_num);
        confllc->link_num = link->link_id;
-       memcpy(confllc->link_uid, lgr->id, SMC_LGR_ID_SIZE);
+       memcpy(confllc->link_uid, link->link_uid, SMC_LGR_ID_SIZE);
        confllc->max_links = SMC_LLC_ADD_LNK_MAX_LINKS;
        /* send llc message */
        rc = smc_wr_tx_send(link, pend);
@@ -845,7 +844,8 @@ int smc_llc_cli_add_link(struct smc_link *link, struct smc_llc_qentry *qentry)
        if (rc)
                goto out_reject;
        smc_llc_save_add_link_info(lnk_new, llc);
-       lnk_new->link_id = llc->link_num;
+       lnk_new->link_id = llc->link_num;       /* SMC server assigns link id */
+       smc_llc_link_set_uid(lnk_new);
 
        rc = smc_ib_ready_link(lnk_new);
        if (rc)
@@ -1775,12 +1775,22 @@ out:
        return rc;
 }
 
+void smc_llc_link_set_uid(struct smc_link *link)
+{
+       __be32 link_uid;
+
+       link_uid = htonl(*((u32 *)link->lgr->id) + link->link_id);
+       memcpy(link->link_uid, &link_uid, SMC_LGR_ID_SIZE);
+}
+
 /* evaluate confirm link request or response */
 int smc_llc_eval_conf_link(struct smc_llc_qentry *qentry,
                           enum smc_llc_reqresp type)
 {
-       if (type == SMC_LLC_REQ)        /* SMC server assigns link_id */
+       if (type == SMC_LLC_REQ) {      /* SMC server assigns link_id */
                qentry->link->link_id = qentry->msg.confirm_link.link_num;
+               smc_llc_link_set_uid(qentry->link);
+       }
        if (!(qentry->msg.raw.hdr.flags & SMC_LLC_FLAG_NO_RMBE_EYEC))
                return -ENOTSUPP;
        return 0;

diff --git a/net/smc/smc_llc.h b/net/smc/smc_llc.h
index f5882eb..1b68f22 100644 (file)
--- a/net/smc/smc_llc.h
+++ b/net/smc/smc_llc.h
@@ -92,6 +92,7 @@ int smc_llc_flow_initiate(struct smc_link_group *lgr,
 void smc_llc_flow_stop(struct smc_link_group *lgr, struct smc_llc_flow *flow);
 int smc_llc_eval_conf_link(struct smc_llc_qentry *qentry,
                           enum smc_llc_reqresp type);
+void smc_llc_link_set_uid(struct smc_link *link);
 struct smc_llc_qentry *smc_llc_wait(struct smc_link_group *lgr,
                                    struct smc_link *lnk,
                                    int time_out, u8 exp_msg);