Support smc release version negotiation in clc handshake. And set
the latest smc release version to 2.1.

Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
---
 net/smc/af_smc.c   | 22 ++++++++++++++++++++--
 net/smc/smc.h      |  5 ++++-
 net/smc/smc_clc.c  | 12 ++++++------
 net/smc/smc_clc.h  | 23 ++++++++++++++++++++++-
 net/smc/smc_core.h |  1 +
 5 files changed, 53 insertions(+), 10 deletions(-)

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index a7f887d91d89..bac73eb0542d 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -1187,6 +1187,11 @@ static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
 			return SMC_CLC_DECL_NOINDIRECT;
 		}
 	}
+
+	if (fce->release > SMC_RELEASE)
+		return SMC_CLC_DECL_VERSMISMAT;
+	ini->release_ver = fce->release;
+
 	return 0;
 }
 
@@ -1355,6 +1360,15 @@ static int smc_connect_ism(struct smc_sock *smc,
 		struct smc_clc_msg_accept_confirm_v2 *aclc_v2 =
 			(struct smc_clc_msg_accept_confirm_v2 *)aclc;
 
+		if (ini->first_contact_peer) {
+			struct smc_clc_first_contact_ext *fce =
+				smc_get_clc_first_contact_ext(aclc_v2, true);
+
+			if (fce->release > SMC_RELEASE)
+				return SMC_CLC_DECL_VERSMISMAT;
+			ini->release_ver = fce->release;
+		}
+
 		rc = smc_v2_determine_accepted_chid(aclc_v2, ini);
 		if (rc)
 			return rc;
@@ -1389,7 +1403,7 @@ static int smc_connect_ism(struct smc_sock *smc,
 	}
 
 	rc = smc_clc_send_confirm(smc, ini->first_contact_local,
-				  aclc->hdr.version, eid, NULL);
+				  aclc->hdr.version, eid, ini);
 	if (rc)
 		goto connect_abort;
 	mutex_unlock(&smc_server_lgr_pending);
@@ -1965,6 +1979,10 @@ static int smc_listen_v2_check(struct smc_sock *new_smc,
 		}
 	}
 
+	ini->release_ver = pclc_v2_ext->hdr.flag.release;
+	if (pclc_v2_ext->hdr.flag.release > SMC_RELEASE)
+		ini->release_ver = SMC_RELEASE;
+
 out:
 	if (!ini->smcd_version && !ini->smcr_version)
 		return rc;
@@ -2412,7 +2430,7 @@ static void smc_listen_work(struct work_struct *work)
 	/* send SMC Accept CLC message */
 	accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
 	rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
-				 accept_version, ini->negotiated_eid);
+				 accept_version, ini->negotiated_eid, ini);
 	if (rc)
 		goto out_unlock;
 
diff --git a/net/smc/smc.h b/net/smc/smc.h
index 2eeea4cdc718..9cce1a41e011 100644
--- a/net/smc/smc.h
+++ b/net/smc/smc.h
@@ -21,7 +21,10 @@
 
 #define SMC_V1		1		/* SMC version V1 */
 #define SMC_V2		2		/* SMC version V2 */
-#define SMC_RELEASE	0
+
+#define SMC_RELEASE_0 0
+#define SMC_RELEASE_1 1
+#define SMC_RELEASE	SMC_RELEASE_1 /* the latest release version */
 
 #define SMCPROTO_SMC		0	/* SMC protocol, IPv4 */
 #define SMCPROTO_SMC6		1	/* SMC protocol, IPv6 */
diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
index b9b8b07aa702..b838ad0749b4 100644
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -420,11 +420,11 @@ smc_clc_msg_decl_valid(struct smc_clc_msg_decline *dclc)
 	return true;
 }
 
-static void smc_clc_fill_fce(struct smc_clc_first_contact_ext *fce, int *len)
+static void smc_clc_fill_fce(struct smc_clc_first_contact_ext *fce, int *len, int release_ver)
 {
 	memset(fce, 0, sizeof(*fce));
 	fce->os_type = SMC_CLC_OS_LINUX;
-	fce->release = SMC_RELEASE;
+	fce->release = release_ver;
 	memcpy(fce->hostname, smc_hostname, sizeof(smc_hostname));
 	(*len) += sizeof(*fce);
 }
@@ -1019,7 +1019,7 @@ static int smc_clc_send_confirm_accept(struct smc_sock *smc,
 				memcpy(clc_v2->d1.eid, eid, SMC_MAX_EID_LEN);
 			len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2;
 			if (first_contact)
-				smc_clc_fill_fce(&fce, &len);
+				smc_clc_fill_fce(&fce, &len, ini->release_ver);
 			clc_v2->hdr.length = htons(len);
 		}
 		memcpy(trl.eyecatcher, SMCD_EYECATCHER,
@@ -1063,7 +1063,7 @@ static int smc_clc_send_confirm_accept(struct smc_sock *smc,
 				memcpy(clc_v2->r1.eid, eid, SMC_MAX_EID_LEN);
 			len = SMCR_CLC_ACCEPT_CONFIRM_LEN_V2;
 			if (first_contact) {
-				smc_clc_fill_fce(&fce, &len);
+				smc_clc_fill_fce(&fce, &len, ini->release_ver);
 				fce.v2_direct = !link->lgr->uses_gateway;
 				memset(&gle, 0, sizeof(gle));
 				if (ini && clc->hdr.type == SMC_CLC_CONFIRM) {
@@ -1141,7 +1141,7 @@ int smc_clc_send_confirm(struct smc_sock *smc, bool clnt_first_contact,
 
 /* send CLC ACCEPT message across internal TCP socket */
 int smc_clc_send_accept(struct smc_sock *new_smc, bool srv_first_contact,
-			u8 version, u8 *negotiated_eid)
+			u8 version, u8 *negotiated_eid, struct smc_init_info *ini)
 {
 	struct smc_clc_msg_accept_confirm_v2 aclc_v2;
 	int len;
@@ -1149,7 +1149,7 @@ int smc_clc_send_accept(struct smc_sock *new_smc, bool srv_first_contact,
 	memset(&aclc_v2, 0, sizeof(aclc_v2));
 	aclc_v2.hdr.type = SMC_CLC_ACCEPT;
 	len = smc_clc_send_confirm_accept(new_smc, &aclc_v2, srv_first_contact,
-					  version, negotiated_eid, NULL);
+					  version, negotiated_eid, ini);
 	if (len < ntohs(aclc_v2.hdr.length))
 		len = len >= 0 ? -EPROTO : -new_smc->clcsock->sk->sk_err;
 
diff --git a/net/smc/smc_clc.h b/net/smc/smc_clc.h
index 5fee545c9a10..b923e89acafb 100644
--- a/net/smc/smc_clc.h
+++ b/net/smc/smc_clc.h
@@ -370,6 +370,27 @@ smc_get_clc_smcd_v2_ext(struct smc_clc_v2_extension *prop_v2ext)
 		 ntohs(prop_v2ext->hdr.smcd_v2_ext_offset));
 }
 
+static inline struct smc_clc_first_contact_ext *
+smc_get_clc_first_contact_ext(struct smc_clc_msg_accept_confirm_v2 *clc_v2,
+			      bool is_smcd)
+{
+	int clc_v2_len;
+
+	if (clc_v2->hdr.version == SMC_V1 ||
+	    !(clc_v2->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
+		return NULL;
+
+	if (is_smcd)
+		clc_v2_len =
+			offsetofend(struct smc_clc_msg_accept_confirm_v2, d1);
+	else
+		clc_v2_len =
+			offsetofend(struct smc_clc_msg_accept_confirm_v2, r1);
+
+	return (struct smc_clc_first_contact_ext *)(((u8 *)clc_v2) +
+						    clc_v2_len);
+}
+
 struct smcd_dev;
 struct smc_init_info;
 
@@ -382,7 +403,7 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini);
 int smc_clc_send_confirm(struct smc_sock *smc, bool clnt_first_contact,
 			 u8 version, u8 *eid, struct smc_init_info *ini);
 int smc_clc_send_accept(struct smc_sock *smc, bool srv_first_contact,
-			u8 version, u8 *negotiated_eid);
+			u8 version, u8 *negotiated_eid, struct smc_init_info *ini);
 void smc_clc_init(void) __init;
 void smc_clc_exit(void);
 void smc_clc_get_hostname(u8 **host);
diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index 3c1b31bfa1cf..1a97fef39127 100644
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -374,6 +374,7 @@ struct smc_init_info {
 	u8			is_smcd;
 	u8			smc_type_v1;
 	u8			smc_type_v2;
+	u8			release_ver;
 	u8			first_contact_peer;
 	u8			first_contact_local;
 	unsigned short		vlan_id;
-- 
2.24.3 (Apple Git-128)

On Thu, Aug 03, 2023 at 09:24:17PM +0800, Guangguan Wang wrote:

...

Hi Guangguan Wang,

> @@ -1063,7 +1063,7 @@ static int smc_clc_send_confirm_accept(struct smc_sock *smc,
>  				memcpy(clc_v2->r1.eid, eid, SMC_MAX_EID_LEN);
>  			len = SMCR_CLC_ACCEPT_CONFIRM_LEN_V2;
>  			if (first_contact) {
> -				smc_clc_fill_fce(&fce, &len);
> +				smc_clc_fill_fce(&fce, &len, ini->release_ver);

Here ini is dereferenced...


>  				fce.v2_direct = !link->lgr->uses_gateway;
>  				memset(&gle, 0, sizeof(gle));
>  				if (ini && clc->hdr.type == SMC_CLC_CONFIRM) {

... but here it is assumed that ini may be NULL.

This seems inconsistent.

As flagged by Smatch.

...

-- 
pw-bot: changes-requested

Hi Simon,

Thanks for the review.

Before this patch set, the ini pointer is NULL when sending accept clc msg. This patch set
has changed the ini pointer to non-NULL value both when sending accept clc msg and when
sending confirm clc msg. And the ini pointer in smc_clc_send_confirm_accept will not be NULL
any more.

I will remove the ini NULL check in the next version.
if (ini && clc->hdr.type == SMC_CLC_CONFIRM) => if (clc->hdr.type == SMC_CLC_CONFIRM)

Thanks,
Guangguan Wang

On 2023/8/4 01:42, Simon Horman wrote:
> On Thu, Aug 03, 2023 at 09:24:17PM +0800, Guangguan Wang wrote:
> 
> ...
> 
> Hi Guangguan Wang,
> 
>> @@ -1063,7 +1063,7 @@ static int smc_clc_send_confirm_accept(struct smc_sock *smc,
>>  				memcpy(clc_v2->r1.eid, eid, SMC_MAX_EID_LEN);
>>  			len = SMCR_CLC_ACCEPT_CONFIRM_LEN_V2;
>>  			if (first_contact) {
>> -				smc_clc_fill_fce(&fce, &len);
>> +				smc_clc_fill_fce(&fce, &len, ini->release_ver);
> 
> Here ini is dereferenced...
> 
> 
>>  				fce.v2_direct = !link->lgr->uses_gateway;
>>  				memset(&gle, 0, sizeof(gle));
>>  				if (ini && clc->hdr.type == SMC_CLC_CONFIRM) {
> 
> ... but here it is assumed that ini may be NULL.
> 
> This seems inconsistent.
> 
> As flagged by Smatch.
> 
> ...
>