net/smc: separate find device functions

This patch provides better separation of device determinations
in function smc_listen_work(). No functional change.

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

3 files changed, 84 insertions, 46 deletions

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 1a02d3665c46..911482741224 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -1188,7 +1188,6 @@ static int smc_listen_rdma_init(struct smc_sock *new_smc,
 
 /* listen worker: initialize connection and buffers for SMC-D */
 static int smc_listen_ism_init(struct smc_sock *new_smc,
-			       struct smc_clc_msg_proposal *pclc,
 			       struct smc_init_info *ini)
 {
 	int rc;
@@ -1211,6 +1210,26 @@ static int smc_listen_ism_init(struct smc_sock *new_smc,
 	return 0;
 }
 
+static void smc_find_ism_device_serv(struct smc_sock *new_smc,
+				     struct smc_clc_msg_proposal *pclc,
+				     struct smc_init_info *ini)
+{
+	struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
+
+	if (!smcd_indicated(pclc->hdr.typev1))
+		goto not_found;
+	ini->is_smcd = true; /* prepare ISM check */
+	ini->ism_peer_gid = pclc_smcd->gid;
+	if (smc_find_ism_device(new_smc, ini))
+		goto not_found;
+	if (!smc_listen_ism_init(new_smc, ini))
+		return;		/* ISM device found */
+
+not_found:
+	ini->ism_dev = NULL;
+	ini->is_smcd = false;
+}
+
 /* listen worker: register buffers */
 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
 {
@@ -1225,6 +1244,47 @@ static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
 	return 0;
 }
 
+static int smc_find_rdma_device_serv(struct smc_sock *new_smc,
+				     struct smc_clc_msg_proposal *pclc,
+				     struct smc_init_info *ini)
+{
+	int rc;
+
+	if (!smcr_indicated(pclc->hdr.typev1))
+		return SMC_CLC_DECL_NOSMCDEV;
+
+	/* prepare RDMA check */
+	ini->ib_lcl = &pclc->lcl;
+	rc = smc_find_rdma_device(new_smc, ini);
+	if (rc) {
+		/* no RDMA device found */
+		if (pclc->hdr.typev1 == SMC_TYPE_B)
+			/* neither ISM nor RDMA device found */
+			rc = SMC_CLC_DECL_NOSMCDEV;
+		return rc;
+	}
+	rc = smc_listen_rdma_init(new_smc, ini);
+	if (rc)
+		return rc;
+	return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
+}
+
+/* determine the local device matching to proposal */
+static int smc_listen_find_device(struct smc_sock *new_smc,
+				  struct smc_clc_msg_proposal *pclc,
+				  struct smc_init_info *ini)
+{
+	/* check if ISM is available */
+	smc_find_ism_device_serv(new_smc, pclc, ini);
+	if (ini->is_smcd)
+		return 0;
+	if (pclc->hdr.typev1 == SMC_TYPE_D)
+		return SMC_CLC_DECL_NOSMCDDEV; /* skip RDMA and decline */
+
+	/* check if RDMA is available */
+	return smc_find_rdma_device_serv(new_smc, pclc, ini);
+}
+
 /* listen worker: finish RDMA setup */
 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
 				  struct smc_clc_msg_accept_confirm *cclc,
@@ -1250,7 +1310,7 @@ static int smc_listen_rdma_finish(struct smc_sock *new_smc,
 	return reason_code;
 }
 
-/* setup for RDMA connection of server */
+/* setup for connection of server */
 static void smc_listen_work(struct work_struct *work)
 {
 	struct smc_sock *new_smc = container_of(work, struct smc_sock,
@@ -1260,7 +1320,6 @@ static void smc_listen_work(struct work_struct *work)
 	struct smc_clc_msg_proposal_area *buf;
 	struct smc_clc_msg_proposal *pclc;
 	struct smc_init_info ini = {0};
-	bool ism_supported = false;
 	int rc = 0;
 
 	if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
@@ -1315,42 +1374,10 @@ static void smc_listen_work(struct work_struct *work)
 	smc_rx_init(new_smc);
 	smc_tx_init(new_smc);
 
-	/* check if ISM is available */
-	if (pclc->hdr.typev1 == SMC_TYPE_D || pclc->hdr.typev1 == SMC_TYPE_B) {
-		struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
-
-		ini.is_smcd = true; /* prepare ISM check */
-		ini.ism_peer_gid = pclc_smcd->gid;
-		rc = smc_find_ism_device(new_smc, &ini);
-		if (!rc)
-			rc = smc_listen_ism_init(new_smc, pclc, &ini);
-		if (!rc)
-			ism_supported = true;
-		else if (pclc->hdr.typev1 == SMC_TYPE_D)
-			goto out_unlock; /* skip RDMA and decline */
-	}
-
-	/* check if RDMA is available */
-	if (!ism_supported) { /* SMC_TYPE_R or SMC_TYPE_B */
-		/* prepare RDMA check */
-		ini.is_smcd = false;
-		ini.ism_dev = NULL;
-		ini.ib_lcl = &pclc->lcl;
-		rc = smc_find_rdma_device(new_smc, &ini);
-		if (rc) {
-			/* no RDMA device found */
-			if (pclc->hdr.typev1 == SMC_TYPE_B)
-				/* neither ISM nor RDMA device found */
-				rc = SMC_CLC_DECL_NOSMCDEV;
-			goto out_unlock;
-		}
-		rc = smc_listen_rdma_init(new_smc, &ini);
-		if (rc)
-			goto out_unlock;
-		rc = smc_listen_rdma_reg(new_smc, ini.first_contact_local);
-		if (rc)
-			goto out_unlock;
-	}
+	/* determine ISM or RoCE device used for connection */
+	rc = smc_listen_find_device(new_smc, pclc, &ini);
+	if (rc)
+		goto out_unlock;
 
 	/* send SMC Accept CLC message */
 	rc = smc_clc_send_accept(new_smc, ini.first_contact_local);
@@ -1358,20 +1385,20 @@ static void smc_listen_work(struct work_struct *work)
 		goto out_unlock;
 
 	/* SMC-D does not need this lock any more */
-	if (ism_supported)
+	if (ini.is_smcd)
 		mutex_unlock(&smc_server_lgr_pending);
 
 	/* receive SMC Confirm CLC message */
 	rc = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc),
 			      SMC_CLC_CONFIRM, CLC_WAIT_TIME);
 	if (rc) {
-		if (!ism_supported)
+		if (!ini.is_smcd)
 			goto out_unlock;
 		goto out_decl;
 	}
 
 	/* finish worker */
-	if (!ism_supported) {
+	if (!ini.is_smcd) {
 		rc = smc_listen_rdma_finish(new_smc, &cclc,
 					    ini.first_contact_local);
 		if (rc)
diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
index 524d2b225640..85b41c125368 100644
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -450,7 +450,7 @@ int smc_clc_send_proposal(struct smc_sock *smc, int smc_type,
 	pclc_base->hdr.type = SMC_CLC_PROPOSAL;
 	pclc_base->hdr.version = SMC_V1;		/* SMC version */
 	pclc_base->hdr.typev1 = smc_type;
-	if (smc_type == SMC_TYPE_R || smc_type == SMC_TYPE_B) {
+	if (smcr_indicated(smc_type)) {
 		/* add SMC-R specifics */
 		memcpy(pclc_base->lcl.id_for_peer, local_systemid,
 		       sizeof(local_systemid));
@@ -459,7 +459,7 @@ int smc_clc_send_proposal(struct smc_sock *smc, int smc_type,
 		       ETH_ALEN);
 		pclc_base->iparea_offset = htons(0);
 	}
-	if (smc_type == SMC_TYPE_D || smc_type == SMC_TYPE_B) {
+	if (smcd_indicated(smc_type)) {
 		/* add SMC-D specifics */
 		plen += sizeof(*pclc_smcd);
 		pclc_base->iparea_offset = htons(sizeof(*pclc_smcd));
@@ -472,7 +472,7 @@ int smc_clc_send_proposal(struct smc_sock *smc, int smc_type,
 	i = 0;
 	vec[i].iov_base = pclc_base;
 	vec[i++].iov_len = sizeof(*pclc_base);
-	if (smc_type == SMC_TYPE_D || smc_type == SMC_TYPE_B) {
+	if (smcd_indicated(smc_type)) {
 		vec[i].iov_base = pclc_smcd;
 		vec[i++].iov_len = sizeof(*pclc_smcd);
 	}
diff --git a/net/smc/smc_clc.h b/net/smc/smc_clc.h
index 5b2d0582886e..5f9fda15f7ff 100644
--- a/net/smc/smc_clc.h
+++ b/net/smc/smc_clc.h
@@ -180,11 +180,22 @@ smc_clc_proposal_get_prefix(struct smc_clc_msg_proposal *pclc)
 	       ((u8 *)pclc + sizeof(*pclc) + ntohs(pclc->iparea_offset));
 }
 
+static inline bool smcr_indicated(int smc_type)
+{
+	return smc_type == SMC_TYPE_R || smc_type == SMC_TYPE_B;
+}
+
+static inline bool smcd_indicated(int smc_type)
+{
+	return smc_type == SMC_TYPE_D || smc_type == SMC_TYPE_B;
+}
+
 /* get SMC-D info from proposal message */
 static inline struct smc_clc_msg_smcd *
 smc_get_clc_msg_smcd(struct smc_clc_msg_proposal *prop)
 {
-	if (ntohs(prop->iparea_offset) != sizeof(struct smc_clc_msg_smcd))
+	if (smcd_indicated(prop->hdr.type) &&
+	    ntohs(prop->iparea_offset) != sizeof(struct smc_clc_msg_smcd))
 		return NULL;
 
 	return (struct smc_clc_msg_smcd *)(prop + 1);