Merge tag 'powerpc-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc...

[linux-2.6-microblaze.git] / net / smc / af_smc.c

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 745f145..6451c50 100644 (file)
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -390,6 +390,12 @@ static int smc_connect_rdma(struct smc_sock *smc)
        int rc = 0;
        u8 ibport;
 
+       if (!tcp_sk(smc->clcsock->sk)->syn_smc) {
+               /* peer has not signalled SMC-capability */
+               smc->use_fallback = true;
+               goto out_connected;
+       }
+
        /* IPSec connections opt out of SMC-R optimizations */
        if (using_ipsec(smc)) {
                reason_code = SMC_CLC_DECL_IPSEC;
@@ -555,6 +561,7 @@ static int smc_connect(struct socket *sock, struct sockaddr *addr,
        }
 
        smc_copy_sock_settings_to_clc(smc);
+       tcp_sk(smc->clcsock->sk)->syn_smc = 1;
        rc = kernel_connect(smc->clcsock, addr, alen, flags);
        if (rc)
                goto out;
@@ -759,6 +766,12 @@ static void smc_listen_work(struct work_struct *work)
        u8 prefix_len;
        u8 ibport;
 
+       /* check if peer is smc capable */
+       if (!tcp_sk(newclcsock->sk)->syn_smc) {
+               new_smc->use_fallback = true;
+               goto out_connected;
+       }
+
        /* do inband token exchange -
         *wait for and receive SMC Proposal CLC message
         */
@@ -808,7 +821,7 @@ static void smc_listen_work(struct work_struct *work)
                rc = local_contact;
                if (rc == -ENOMEM)
                        reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/
-               goto decline_rdma;
+               goto decline_rdma_unlock;
        }
        link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
 
@@ -816,7 +829,7 @@ static void smc_listen_work(struct work_struct *work)
        rc = smc_buf_create(new_smc);
        if (rc) {
                reason_code = SMC_CLC_DECL_MEM;
-               goto decline_rdma;
+               goto decline_rdma_unlock;
        }
 
        smc_close_init(new_smc);
@@ -831,7 +844,7 @@ static void smc_listen_work(struct work_struct *work)
                                             buf_desc->mr_rx[SMC_SINGLE_LINK]);
                        if (rc) {
                                reason_code = SMC_CLC_DECL_INTERR;
-                               goto decline_rdma;
+                               goto decline_rdma_unlock;
                        }
                }
        }
@@ -839,15 +852,15 @@ static void smc_listen_work(struct work_struct *work)
 
        rc = smc_clc_send_accept(new_smc, local_contact);
        if (rc)
-               goto out_err;
+               goto out_err_unlock;
 
        /* receive SMC Confirm CLC message */
        reason_code = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc),
                                       SMC_CLC_CONFIRM);
        if (reason_code < 0)
-               goto out_err;
+               goto out_err_unlock;
        if (reason_code > 0)
-               goto decline_rdma;
+               goto decline_rdma_unlock;
        smc_conn_save_peer_info(new_smc, &cclc);
        if (local_contact == SMC_FIRST_CONTACT)
                smc_link_save_peer_info(link, &cclc);
@@ -855,34 +868,34 @@ static void smc_listen_work(struct work_struct *work)
        rc = smc_rmb_rtoken_handling(&new_smc->conn, &cclc);
        if (rc) {
                reason_code = SMC_CLC_DECL_INTERR;
-               goto decline_rdma;
+               goto decline_rdma_unlock;
        }
 
        if (local_contact == SMC_FIRST_CONTACT) {
                rc = smc_ib_ready_link(link);
                if (rc) {
                        reason_code = SMC_CLC_DECL_INTERR;
-                       goto decline_rdma;
+                       goto decline_rdma_unlock;
                }
                /* QP confirmation over RoCE fabric */
                reason_code = smc_serv_conf_first_link(new_smc);
                if (reason_code < 0) {
                        /* peer is not aware of a problem */
                        rc = reason_code;
-                       goto out_err;
+                       goto out_err_unlock;
                }
                if (reason_code > 0)
-                       goto decline_rdma;
+                       goto decline_rdma_unlock;
        }
 
        smc_tx_init(new_smc);
+       mutex_unlock(&smc_create_lgr_pending);
 
 out_connected:
        sk_refcnt_debug_inc(newsmcsk);
        if (newsmcsk->sk_state == SMC_INIT)
                newsmcsk->sk_state = SMC_ACTIVE;
 enqueue:
-       mutex_unlock(&smc_create_lgr_pending);
        lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
        if (lsmc->sk.sk_state == SMC_LISTEN) {
                smc_accept_enqueue(&lsmc->sk, newsmcsk);
@@ -896,6 +909,8 @@ enqueue:
        sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
        return;
 
+decline_rdma_unlock:
+       mutex_unlock(&smc_create_lgr_pending);
 decline_rdma:
        /* RDMA setup failed, switch back to TCP */
        smc_conn_free(&new_smc->conn);
@@ -907,6 +922,8 @@ decline_rdma:
        }
        goto out_connected;
 
+out_err_unlock:
+       mutex_unlock(&smc_create_lgr_pending);
 out_err:
        newsmcsk->sk_state = SMC_CLOSED;
        smc_conn_free(&new_smc->conn);
@@ -963,6 +980,7 @@ static int smc_listen(struct socket *sock, int backlog)
         * them to the clc socket -- copy smc socket options to clc socket
         */
        smc_copy_sock_settings_to_clc(smc);
+       tcp_sk(smc->clcsock->sk)->syn_smc = 1;
 
        rc = kernel_listen(smc->clcsock, backlog);
        if (rc)
@@ -1405,6 +1423,7 @@ static int __init smc_init(void)
                goto out_sock;
        }
 
+       static_branch_enable(&tcp_have_smc);
        return 0;
 
 out_sock:
@@ -1429,6 +1448,7 @@ static void __exit smc_exit(void)
                list_del_init(&lgr->list);
                smc_lgr_free(lgr); /* free link group */
        }
+       static_branch_disable(&tcp_have_smc);
        smc_ib_unregister_client();
        sock_unregister(PF_SMC);
        proto_unregister(&smc_proto);