[PATCH net-next v5 0/9] net/smc: implement SMCv2.1 virtual ISM device support

[PATCH net-next v5 0/9] net/smc: implement SMCv2.1 virtual ISM device support

[Wen Gu]

The fourth edition of SMCv2 adds the SMC version 2.1 feature updates for
SMC-Dv2 with virtual ISM. Virtual ISM are created and supported mainly by
OS or hypervisor software, comparable to IBM ISM which is based on platform
firmware or hardware.

With the introduction of virtual ISM, SMCv2.1 makes some updates:

- Introduce feature bitmask to indicate supplemental features.
- Reserve a range of CHIDs for virtual ISM.
- Support extended GIDs (128 bits) in CLC handshake.

So this patch set aims to implement these updates in Linux kernel. And it
acts as the first part of SMC-D virtual ISM extension & loopback-ism [1].

[1] https://lore.kernel.org/netdev/1695568613-125057-1-git-send-email-guwen@linux.alibaba.com/

v5->v4:
- Patch #6: improve the comment of SMCD_CLC_MAX_V2_GID_ENTRIES;
- Patch #4: remove useless ini->feature_mask assignment;

v4->v3:
- Patch #6: use SMCD_CLC_MAX_V2_GID_ENTRIES to indicate the max gid
  entries in CLC proposal and using SMC_MAX_V2_ISM_DEVS to indicate the
  max devices to propose;
- Patch #6: use i and i+1 in smc_find_ism_v2_device_serv();
- Patch #2: replace the large if-else block in smc_clc_send_confirm_accept()
  with 2 subfunctions;
- Fix missing byte order conversion of GID and token in CLC handshake,
  which is in a separate patch sending to net:
  https://lore.kernel.org/netdev/1701882157-87956-1-git-send-email-guwen@linux.alibaba.com/
- Patch #7: add extended GID in SMC-D lgr netlink attribute;

v3->v2:
- Rename smc_clc_fill_fce as smc_clc_fill_fce_v2x;
- Remove ISM_IDENT_MASK from drivers/s390/net/ism.h;
- Add explicitly assigning 'false' to ism_v2_capable in ism_dev_init();
- Remove smc_ism_set_v2_capable() helper for now, and introduce it in
  later loopback-ism implementation;

v2->v1:
- Fix sparse complaint;
- Rebase to the latest net-next;

Wen Gu (9):
  net/smc: rename some 'fce' to 'fce_v2x' for clarity
  net/smc: introduce sub-functions for smc_clc_send_confirm_accept()
  net/smc: support SMCv2.x supplemental features negotiation
  net/smc: introduce virtual ISM device support feature
  net/smc: define a reserved CHID range for virtual ISM devices
  net/smc: compatible with 128-bits extended GID of virtual ISM device
  net/smc: support extended GID in SMC-D lgr netlink attribute
  net/smc: disable SEID on non-s390 archs where virtual ISM may be used
  net/smc: manage system EID in SMC stack instead of ISM driver

 drivers/s390/net/ism.h        |   7 --
 drivers/s390/net/ism_drv.c    |  57 +++------
 include/linux/ism.h           |   1 -
 include/net/smc.h             |  16 ++-
 include/uapi/linux/smc.h      |   2 +
 include/uapi/linux/smc_diag.h |   2 +
 net/smc/af_smc.c              |  66 ++++++++--
 net/smc/smc.h                 |  10 +-
 net/smc/smc_clc.c             | 278 +++++++++++++++++++++++++++---------------
 net/smc/smc_clc.h             |  26 ++--
 net/smc/smc_core.c            |  37 ++++--
 net/smc/smc_core.h            |  18 ++-
 net/smc/smc_diag.c            |   9 +-
 net/smc/smc_ism.c             |  50 +++++---
 net/smc/smc_ism.h             |  30 ++++-
 net/smc/smc_pnet.c            |   4 +-
 16 files changed, 400 insertions(+), 213 deletions(-)

-- 
1.8.3.1

[PATCH net-next v5 1/9] net/smc: rename some 'fce' to 'fce_v2x' for clarity

[Wen Gu]

Rename some functions or variables with 'fce' in their name but used in
SMCv2.1 as 'fce_v2x' for clarity.

Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
---
 net/smc/smc_clc.c | 30 ++++++++++++++++--------------
 1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
index 95e19aa..0fcb035 100644
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -418,15 +418,16 @@ static bool smc_clc_msg_prop_valid(struct smc_clc_msg_proposal *pclc)
 	return true;
 }
 
-static int smc_clc_fill_fce(struct smc_clc_first_contact_ext_v2x *fce,
-			    struct smc_init_info *ini)
+static int smc_clc_fill_fce_v2x(struct smc_clc_first_contact_ext_v2x *fce_v2x,
+				struct smc_init_info *ini)
 {
-	int ret = sizeof(*fce);
+	int ret = sizeof(*fce_v2x);
 
-	memset(fce, 0, sizeof(*fce));
-	fce->fce_v2_base.os_type = SMC_CLC_OS_LINUX;
-	fce->fce_v2_base.release = ini->release_nr;
-	memcpy(fce->fce_v2_base.hostname, smc_hostname, sizeof(smc_hostname));
+	memset(fce_v2x, 0, sizeof(*fce_v2x));
+	fce_v2x->fce_v2_base.os_type = SMC_CLC_OS_LINUX;
+	fce_v2x->fce_v2_base.release = ini->release_nr;
+	memcpy(fce_v2x->fce_v2_base.hostname,
+	       smc_hostname, sizeof(smc_hostname));
 	if (ini->is_smcd && ini->release_nr < SMC_RELEASE_1) {
 		ret = sizeof(struct smc_clc_first_contact_ext);
 		goto out;
@@ -434,8 +435,8 @@ static int smc_clc_fill_fce(struct smc_clc_first_contact_ext_v2x *fce,
 
 	if (ini->release_nr >= SMC_RELEASE_1) {
 		if (!ini->is_smcd) {
-			fce->max_conns = ini->max_conns;
-			fce->max_links = ini->max_links;
+			fce_v2x->max_conns = ini->max_conns;
+			fce_v2x->max_links = ini->max_links;
 		}
 	}
 
@@ -1003,8 +1004,8 @@ static int smc_clc_send_confirm_accept(struct smc_sock *smc,
 				       int first_contact, u8 version,
 				       u8 *eid, struct smc_init_info *ini)
 {
+	struct smc_clc_first_contact_ext_v2x fce_v2x;
 	struct smc_connection *conn = &smc->conn;
-	struct smc_clc_first_contact_ext_v2x fce;
 	struct smcd_dev *smcd = conn->lgr->smcd;
 	struct smc_clc_msg_accept_confirm *clc;
 	struct smc_clc_fce_gid_ext gle;
@@ -1036,7 +1037,7 @@ 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) {
-				fce_len = smc_clc_fill_fce(&fce, ini);
+				fce_len = smc_clc_fill_fce_v2x(&fce_v2x, ini);
 				len += fce_len;
 			}
 			clc_v2->hdr.length = htons(len);
@@ -1082,9 +1083,10 @@ 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) {
-				fce_len = smc_clc_fill_fce(&fce, ini);
+				fce_len = smc_clc_fill_fce_v2x(&fce_v2x, ini);
 				len += fce_len;
-				fce.fce_v2_base.v2_direct = !link->lgr->uses_gateway;
+				fce_v2x.fce_v2_base.v2_direct =
+					!link->lgr->uses_gateway;
 				if (clc->hdr.type == SMC_CLC_CONFIRM) {
 					memset(&gle, 0, sizeof(gle));
 					gle.gid_cnt = ini->smcrv2.gidlist.len;
@@ -1111,7 +1113,7 @@ static int smc_clc_send_confirm_accept(struct smc_sock *smc,
 						SMCR_CLC_ACCEPT_CONFIRM_LEN) -
 				   sizeof(trl);
 	if (version > SMC_V1 && first_contact) {
-		vec[i].iov_base = &fce;
+		vec[i].iov_base = &fce_v2x;
 		vec[i++].iov_len = fce_len;
 		if (!conn->lgr->is_smcd) {
 			if (clc->hdr.type == SMC_CLC_CONFIRM) {
-- 
1.8.3.1

[PATCH net-next v5 2/9] net/smc: introduce sub-functions for smc_clc_send_confirm_accept()

[Wen Gu]

There is a large if-else block in smc_clc_send_confirm_accept() and it
is better to split it into two sub-functions.

Suggested-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
---
 net/smc/smc_clc.c | 196 +++++++++++++++++++++++++++++++-----------------------
 1 file changed, 114 insertions(+), 82 deletions(-)

diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
index 0fcb035..52b4ea9 100644
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -998,6 +998,111 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
 	return reason_code;
 }
 
+static void smcd_clc_prep_confirm_accept(struct smc_connection *conn,
+				struct smc_clc_msg_accept_confirm_v2 *clc_v2,
+				int first_contact, u8 version,
+				u8 *eid, struct smc_init_info *ini,
+				int *fce_len,
+				struct smc_clc_first_contact_ext_v2x *fce_v2x,
+				struct smc_clc_msg_trail *trl)
+{
+	struct smcd_dev *smcd = conn->lgr->smcd;
+	struct smc_clc_msg_accept_confirm *clc;
+	int len;
+
+	/* SMC-D specific settings */
+	clc = (struct smc_clc_msg_accept_confirm *)clc_v2;
+	memcpy(clc->hdr.eyecatcher, SMCD_EYECATCHER,
+	       sizeof(SMCD_EYECATCHER));
+	clc->hdr.typev1 = SMC_TYPE_D;
+	clc->d0.gid = htonll(smcd->ops->get_local_gid(smcd));
+	clc->d0.token = htonll(conn->rmb_desc->token);
+	clc->d0.dmbe_size = conn->rmbe_size_comp;
+	clc->d0.dmbe_idx = 0;
+	memcpy(&clc->d0.linkid, conn->lgr->id, SMC_LGR_ID_SIZE);
+	if (version == SMC_V1) {
+		clc->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
+	} else {
+		clc_v2->d1.chid = htons(smc_ism_get_chid(smcd));
+		if (eid && eid[0])
+			memcpy(clc_v2->d1.eid, eid, SMC_MAX_EID_LEN);
+		len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2;
+		if (first_contact) {
+			*fce_len = smc_clc_fill_fce_v2x(fce_v2x, ini);
+			len += *fce_len;
+		}
+		clc_v2->hdr.length = htons(len);
+	}
+	memcpy(trl->eyecatcher, SMCD_EYECATCHER,
+	       sizeof(SMCD_EYECATCHER));
+}
+
+static void smcr_clc_prep_confirm_accept(struct smc_connection *conn,
+				struct smc_clc_msg_accept_confirm_v2 *clc_v2,
+				int first_contact, u8 version,
+				u8 *eid, struct smc_init_info *ini,
+				int *fce_len,
+				struct smc_clc_first_contact_ext_v2x *fce_v2x,
+				struct smc_clc_fce_gid_ext *gle,
+				struct smc_clc_msg_trail *trl)
+{
+	struct smc_clc_msg_accept_confirm *clc;
+	struct smc_link *link = conn->lnk;
+	int len;
+
+	/* SMC-R specific settings */
+	clc = (struct smc_clc_msg_accept_confirm *)clc_v2;
+	memcpy(clc->hdr.eyecatcher, SMC_EYECATCHER,
+	       sizeof(SMC_EYECATCHER));
+	clc->hdr.typev1 = SMC_TYPE_R;
+	clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
+	memcpy(clc->r0.lcl.id_for_peer, local_systemid,
+	       sizeof(local_systemid));
+	memcpy(&clc->r0.lcl.gid, link->gid, SMC_GID_SIZE);
+	memcpy(&clc->r0.lcl.mac, &link->smcibdev->mac[link->ibport - 1],
+	       ETH_ALEN);
+	hton24(clc->r0.qpn, link->roce_qp->qp_num);
+	clc->r0.rmb_rkey =
+		htonl(conn->rmb_desc->mr[link->link_idx]->rkey);
+	clc->r0.rmbe_idx = 1; /* for now: 1 RMB = 1 RMBE */
+	clc->r0.rmbe_alert_token = htonl(conn->alert_token_local);
+	switch (clc->hdr.type) {
+	case SMC_CLC_ACCEPT:
+		clc->r0.qp_mtu = link->path_mtu;
+		break;
+	case SMC_CLC_CONFIRM:
+		clc->r0.qp_mtu = min(link->path_mtu, link->peer_mtu);
+		break;
+	}
+	clc->r0.rmbe_size = conn->rmbe_size_comp;
+	clc->r0.rmb_dma_addr = conn->rmb_desc->is_vm ?
+		cpu_to_be64((uintptr_t)conn->rmb_desc->cpu_addr) :
+		cpu_to_be64((u64)sg_dma_address
+			    (conn->rmb_desc->sgt[link->link_idx].sgl));
+	hton24(clc->r0.psn, link->psn_initial);
+	if (version == SMC_V1) {
+		clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
+	} else {
+		if (eid && eid[0])
+			memcpy(clc_v2->r1.eid, eid, SMC_MAX_EID_LEN);
+		len = SMCR_CLC_ACCEPT_CONFIRM_LEN_V2;
+		if (first_contact) {
+			*fce_len = smc_clc_fill_fce_v2x(fce_v2x, ini);
+			len += *fce_len;
+			fce_v2x->fce_v2_base.v2_direct =
+				!link->lgr->uses_gateway;
+			if (clc->hdr.type == SMC_CLC_CONFIRM) {
+				memset(gle, 0, sizeof(*gle));
+				gle->gid_cnt = ini->smcrv2.gidlist.len;
+				len += sizeof(*gle);
+				len += gle->gid_cnt * sizeof(gle->gid[0]);
+			}
+		}
+		clc_v2->hdr.length = htons(len);
+	}
+	memcpy(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
+}
+
 /* build and send CLC CONFIRM / ACCEPT message */
 static int smc_clc_send_confirm_accept(struct smc_sock *smc,
 				       struct smc_clc_msg_accept_confirm_v2 *clc_v2,
@@ -1006,11 +1111,10 @@ static int smc_clc_send_confirm_accept(struct smc_sock *smc,
 {
 	struct smc_clc_first_contact_ext_v2x fce_v2x;
 	struct smc_connection *conn = &smc->conn;
-	struct smcd_dev *smcd = conn->lgr->smcd;
 	struct smc_clc_msg_accept_confirm *clc;
 	struct smc_clc_fce_gid_ext gle;
 	struct smc_clc_msg_trail trl;
-	int i, len, fce_len;
+	int i, fce_len;
 	struct kvec vec[5];
 	struct msghdr msg;
 
@@ -1019,86 +1123,14 @@ static int smc_clc_send_confirm_accept(struct smc_sock *smc,
 	clc->hdr.version = version;	/* SMC version */
 	if (first_contact)
 		clc->hdr.typev2 |= SMC_FIRST_CONTACT_MASK;
-	if (conn->lgr->is_smcd) {
-		/* SMC-D specific settings */
-		memcpy(clc->hdr.eyecatcher, SMCD_EYECATCHER,
-		       sizeof(SMCD_EYECATCHER));
-		clc->hdr.typev1 = SMC_TYPE_D;
-		clc->d0.gid = htonll(smcd->ops->get_local_gid(smcd));
-		clc->d0.token = htonll(conn->rmb_desc->token);
-		clc->d0.dmbe_size = conn->rmbe_size_comp;
-		clc->d0.dmbe_idx = 0;
-		memcpy(&clc->d0.linkid, conn->lgr->id, SMC_LGR_ID_SIZE);
-		if (version == SMC_V1) {
-			clc->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
-		} else {
-			clc_v2->d1.chid = htons(smc_ism_get_chid(smcd));
-			if (eid && eid[0])
-				memcpy(clc_v2->d1.eid, eid, SMC_MAX_EID_LEN);
-			len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2;
-			if (first_contact) {
-				fce_len = smc_clc_fill_fce_v2x(&fce_v2x, ini);
-				len += fce_len;
-			}
-			clc_v2->hdr.length = htons(len);
-		}
-		memcpy(trl.eyecatcher, SMCD_EYECATCHER,
-		       sizeof(SMCD_EYECATCHER));
-	} else {
-		struct smc_link *link = conn->lnk;
-
-		/* SMC-R specific settings */
-		memcpy(clc->hdr.eyecatcher, SMC_EYECATCHER,
-		       sizeof(SMC_EYECATCHER));
-		clc->hdr.typev1 = SMC_TYPE_R;
-		clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
-		memcpy(clc->r0.lcl.id_for_peer, local_systemid,
-		       sizeof(local_systemid));
-		memcpy(&clc->r0.lcl.gid, link->gid, SMC_GID_SIZE);
-		memcpy(&clc->r0.lcl.mac, &link->smcibdev->mac[link->ibport - 1],
-		       ETH_ALEN);
-		hton24(clc->r0.qpn, link->roce_qp->qp_num);
-		clc->r0.rmb_rkey =
-			htonl(conn->rmb_desc->mr[link->link_idx]->rkey);
-		clc->r0.rmbe_idx = 1; /* for now: 1 RMB = 1 RMBE */
-		clc->r0.rmbe_alert_token = htonl(conn->alert_token_local);
-		switch (clc->hdr.type) {
-		case SMC_CLC_ACCEPT:
-			clc->r0.qp_mtu = link->path_mtu;
-			break;
-		case SMC_CLC_CONFIRM:
-			clc->r0.qp_mtu = min(link->path_mtu, link->peer_mtu);
-			break;
-		}
-		clc->r0.rmbe_size = conn->rmbe_size_comp;
-		clc->r0.rmb_dma_addr = conn->rmb_desc->is_vm ?
-			cpu_to_be64((uintptr_t)conn->rmb_desc->cpu_addr) :
-			cpu_to_be64((u64)sg_dma_address
-				    (conn->rmb_desc->sgt[link->link_idx].sgl));
-		hton24(clc->r0.psn, link->psn_initial);
-		if (version == SMC_V1) {
-			clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
-		} else {
-			if (eid && eid[0])
-				memcpy(clc_v2->r1.eid, eid, SMC_MAX_EID_LEN);
-			len = SMCR_CLC_ACCEPT_CONFIRM_LEN_V2;
-			if (first_contact) {
-				fce_len = smc_clc_fill_fce_v2x(&fce_v2x, ini);
-				len += fce_len;
-				fce_v2x.fce_v2_base.v2_direct =
-					!link->lgr->uses_gateway;
-				if (clc->hdr.type == SMC_CLC_CONFIRM) {
-					memset(&gle, 0, sizeof(gle));
-					gle.gid_cnt = ini->smcrv2.gidlist.len;
-					len += sizeof(gle);
-					len += gle.gid_cnt * sizeof(gle.gid[0]);
-				}
-			}
-			clc_v2->hdr.length = htons(len);
-		}
-		memcpy(trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
-	}
-
+	if (conn->lgr->is_smcd)
+		smcd_clc_prep_confirm_accept(conn, clc_v2, first_contact,
+					     version, eid, ini, &fce_len,
+					     &fce_v2x, &trl);
+	else
+		smcr_clc_prep_confirm_accept(conn, clc_v2, first_contact,
+					     version, eid, ini, &fce_len,
+					     &fce_v2x, &gle, &trl);
 	memset(&msg, 0, sizeof(msg));
 	i = 0;
 	vec[i].iov_base = clc_v2;
-- 
1.8.3.1

Re: [PATCH net-next v5 2/9] net/smc: introduce sub-functions for smc_clc_send_confirm_accept()

[Wen Gu]

On 2023/12/8 15:40, Wen Gu wrote:

> There is a large if-else block in smc_clc_send_confirm_accept() and it
> is better to split it into two sub-functions.
> 
> Suggested-by: Alexandra Winter <wintera@linux.ibm.com>
> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
> ---
>   net/smc/smc_clc.c | 196 +++++++++++++++++++++++++++++++-----------------------
>   1 file changed, 114 insertions(+), 82 deletions(-)
> 
> diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
> index 0fcb035..52b4ea9 100644
> --- a/net/smc/smc_clc.c
> +++ b/net/smc/smc_clc.c
> @@ -998,6 +998,111 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
>   	return reason_code;
>   }
>   
> +static void smcd_clc_prep_confirm_accept(struct smc_connection *conn,
> +				struct smc_clc_msg_accept_confirm_v2 *clc_v2,

checkpatch will complain 'Alignment should match open parenthesis' here.
But in order to make the length less than 80 columns, there seems to be
no other good way.

> +				int first_contact, u8 version,
> +				u8 *eid, struct smc_init_info *ini,
> +				int *fce_len,
> +				struct smc_clc_first_contact_ext_v2x *fce_v2x,
> +				struct smc_clc_msg_trail *trl)
> +{
<...>

> +
> +static void smcr_clc_prep_confirm_accept(struct smc_connection *conn,
> +				struct smc_clc_msg_accept_confirm_v2 *clc_v2,

And here.

> +				int first_contact, u8 version,
> +				u8 *eid, struct smc_init_info *ini,
> +				int *fce_len,
> +				struct smc_clc_first_contact_ext_v2x *fce_v2x,
> +				struct smc_clc_fce_gid_ext *gle,
> +				struct smc_clc_msg_trail *trl)
> +{
<...>

Re: [PATCH net-next v5 2/9] net/smc: introduce sub-functions for smc_clc_send_confirm_accept()

[Alexandra Winter]

On 09.12.23 03:50, Wen Gu wrote:
> 
> 
> On 2023/12/8 15:40, Wen Gu wrote:
> 
>> There is a large if-else block in smc_clc_send_confirm_accept() and it
>> is better to split it into two sub-functions.
>>
>> Suggested-by: Alexandra Winter <wintera@linux.ibm.com>
>> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
>> ---
>>   net/smc/smc_clc.c | 196 +++++++++++++++++++++++++++++++-----------------------
>>   1 file changed, 114 insertions(+), 82 deletions(-)
>>
>> diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
>> index 0fcb035..52b4ea9 100644
>> --- a/net/smc/smc_clc.c
>> +++ b/net/smc/smc_clc.c
>> @@ -998,6 +998,111 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
>>       return reason_code;
>>   }
>>   +static void smcd_clc_prep_confirm_accept(struct smc_connection *conn,
>> +                struct smc_clc_msg_accept_confirm_v2 *clc_v2,
> 
> checkpatch will complain 'Alignment should match open parenthesis' here.
> But in order to make the length less than 80 columns, there seems to be
> no other good way.
> 
>> +                int first_contact, u8 version,
>> +                u8 *eid, struct smc_init_info *ini,
>> +                int *fce_len,
>> +                struct smc_clc_first_contact_ext_v2x *fce_v2x,
>> +                struct smc_clc_msg_trail *trl)
>> +{
> <...>
> 
>> +
>> +static void smcr_clc_prep_confirm_accept(struct smc_connection *conn,
>> +                struct smc_clc_msg_accept_confirm_v2 *clc_v2,
> 
> And here.
> 
>> +                int first_contact, u8 version,
>> +                u8 *eid, struct smc_init_info *ini,
>> +                int *fce_len,
>> +                struct smc_clc_first_contact_ext_v2x *fce_v2x,
>> +                struct smc_clc_fce_gid_ext *gle,
>> +                struct smc_clc_msg_trail *trl)
>> +{
> <...>
> 


You could shorten the names of the functions

Re: [PATCH net-next v5 2/9] net/smc: introduce sub-functions for smc_clc_send_confirm_accept()

[Wen Gu]

On 2023/12/11 17:47, Alexandra Winter wrote:
> 
> 
> On 09.12.23 03:50, Wen Gu wrote:
>>
>>
>> On 2023/12/8 15:40, Wen Gu wrote:
>>
>>> There is a large if-else block in smc_clc_send_confirm_accept() and it
>>> is better to split it into two sub-functions.
>>>
>>> Suggested-by: Alexandra Winter <wintera@linux.ibm.com>
>>> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
>>> ---
>>>    net/smc/smc_clc.c | 196 +++++++++++++++++++++++++++++++-----------------------
>>>    1 file changed, 114 insertions(+), 82 deletions(-)
>>>
>>> diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
>>> index 0fcb035..52b4ea9 100644
>>> --- a/net/smc/smc_clc.c
>>> +++ b/net/smc/smc_clc.c
>>> @@ -998,6 +998,111 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
>>>        return reason_code;
>>>    }
>>>    +static void smcd_clc_prep_confirm_accept(struct smc_connection *conn,
>>> +                struct smc_clc_msg_accept_confirm_v2 *clc_v2,
>>
>> checkpatch will complain 'Alignment should match open parenthesis' here.
>> But in order to make the length less than 80 columns, there seems to be
>> no other good way.
>>
>>> +                int first_contact, u8 version,
>>> +                u8 *eid, struct smc_init_info *ini,
>>> +                int *fce_len,
>>> +                struct smc_clc_first_contact_ext_v2x *fce_v2x,
>>> +                struct smc_clc_msg_trail *trl)
>>> +{
>> <...>
>>
>>> +
>>> +static void smcr_clc_prep_confirm_accept(struct smc_connection *conn,
>>> +                struct smc_clc_msg_accept_confirm_v2 *clc_v2,
>>
>> And here.
>>
>>> +                int first_contact, u8 version,
>>> +                u8 *eid, struct smc_init_info *ini,
>>> +                int *fce_len,
>>> +                struct smc_clc_first_contact_ext_v2x *fce_v2x,
>>> +                struct smc_clc_fce_gid_ext *gle,
>>> +                struct smc_clc_msg_trail *trl)
>>> +{
>> <...>
>>
> 
> 
> You could shorten the names of the functions

Thank you. I thought about that too, but I think shortening the name may
have an impact on the understanding.



I think the following may be another way out and checkpatch is happy:

+static void
+smcd_clc_prep_confirm_accept(struct smc_connection *conn,
+                             struct smc_clc_msg_accept_confirm_v2 *clc_v2,
+                             int first_contact, u8 version,
+                             u8 *eid, struct smc_init_info *ini,
+                             int *fce_len,
+                             struct smc_clc_first_contact_ext_v2x *fce_v2x,
+                             struct smc_clc_msg_trail *trl)

and

+static void
+smcr_clc_prep_confirm_accept(struct smc_connection *conn,
+                             struct smc_clc_msg_accept_confirm_v2 *clc_v2,
+                             int first_contact, u8 version,
+                             u8 *eid, struct smc_init_info *ini,
+                             int *fce_len,
+                             struct smc_clc_first_contact_ext_v2x *fce_v2x,
+                             struct smc_clc_fce_gid_ext *gle,
+                             struct smc_clc_msg_trail *trl)

Re: [PATCH net-next v5 2/9] net/smc: introduce sub-functions for smc_clc_send_confirm_accept()

[Alexandra Winter]

On 08.12.23 08:40, Wen Gu wrote:
> There is a large if-else block in smc_clc_send_confirm_accept() and it
> is better to split it into two sub-functions.
> 
> Suggested-by: Alexandra Winter <wintera@linux.ibm.com>
> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
> ---

Thank you very much Wen Gu for improving the codebase.


>  net/smc/smc_clc.c | 196 +++++++++++++++++++++++++++++++-----------------------
>  1 file changed, 114 insertions(+), 82 deletions(-)
> 
> diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
> index 0fcb035..52b4ea9 100644
> --- a/net/smc/smc_clc.c
> +++ b/net/smc/smc_clc.c
> @@ -998,6 +998,111 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
>  	return reason_code;
>  }
>  
> +static void smcd_clc_prep_confirm_accept(struct smc_connection *conn,
> +				struct smc_clc_msg_accept_confirm_v2 *clc_v2,
> +				int first_contact, u8 version,
> +				u8 *eid, struct smc_init_info *ini,
> +				int *fce_len,
> +				struct smc_clc_first_contact_ext_v2x *fce_v2x,
> +				struct smc_clc_msg_trail *trl)
> +{
> +	struct smcd_dev *smcd = conn->lgr->smcd;
> +	struct smc_clc_msg_accept_confirm *clc;
> +	int len;
> +
> +	/* SMC-D specific settings */
> +	clc = (struct smc_clc_msg_accept_confirm *)clc_v2;

Why is this cast neccessary? (Here as well as in smcr_clc_prep_confirm_accept
and in smc_clc_send_confirm_accept)
smc_clc_msg_accept_confirm_v2 has hdr and d0 as well.

IMO, it would be a nice seperate patch to get rid of the 2 type defs for
smc_clc_msg_accept_confirm and smc_clc_msg_accept_confirm_v2
and all the related casting anyhow.



> +	memcpy(clc->hdr.eyecatcher, SMCD_EYECATCHER,
> +	       sizeof(SMCD_EYECATCHER));
> +	clc->hdr.typev1 = SMC_TYPE_D;
> +	clc->d0.gid = htonll(smcd->ops->get_local_gid(smcd));
> +	clc->d0.token = htonll(conn->rmb_desc->token);
> +	clc->d0.dmbe_size = conn->rmbe_size_comp;
> +	clc->d0.dmbe_idx = 0;
> +	memcpy(&clc->d0.linkid, conn->lgr->id, SMC_LGR_ID_SIZE);
> +	if (version == SMC_V1) {
> +		clc->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
> +	} else {
> +		clc_v2->d1.chid = htons(smc_ism_get_chid(smcd));
> +		if (eid && eid[0])
> +			memcpy(clc_v2->d1.eid, eid, SMC_MAX_EID_LEN);
> +		len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2;
> +		if (first_contact) {
> +			*fce_len = smc_clc_fill_fce_v2x(fce_v2x, ini);
> +			len += *fce_len;
> +		}
> +		clc_v2->hdr.length = htons(len);
> +	}
> +	memcpy(trl->eyecatcher, SMCD_EYECATCHER,
> +	       sizeof(SMCD_EYECATCHER));
> +}
> +
> +static void smcr_clc_prep_confirm_accept(struct smc_connection *conn,
> +				struct smc_clc_msg_accept_confirm_v2 *clc_v2,
> +				int first_contact, u8 version,
> +				u8 *eid, struct smc_init_info *ini,
> +				int *fce_len,
> +				struct smc_clc_first_contact_ext_v2x *fce_v2x,
> +				struct smc_clc_fce_gid_ext *gle,
> +				struct smc_clc_msg_trail *trl)
> +{
> +	struct smc_clc_msg_accept_confirm *clc;
> +	struct smc_link *link = conn->lnk;
> +	int len;
> +
> +	/* SMC-R specific settings */
> +	clc = (struct smc_clc_msg_accept_confirm *)clc_v2;

Why is this cast neccessary? 
smc_clc_msg_accept_confirm_v2 has hdr and r0 as well.

> +	memcpy(clc->hdr.eyecatcher, SMC_EYECATCHER,
> +	       sizeof(SMC_EYECATCHER));
> +	clc->hdr.typev1 = SMC_TYPE_R;
> +	clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);

^^ this is overwritten below, so no need to set it here.

> +	memcpy(clc->r0.lcl.id_for_peer, local_systemid,
> +	       sizeof(local_systemid));
> +	memcpy(&clc->r0.lcl.gid, link->gid, SMC_GID_SIZE);
> +	memcpy(&clc->r0.lcl.mac, &link->smcibdev->mac[link->ibport - 1],
> +	       ETH_ALEN);
> +	hton24(clc->r0.qpn, link->roce_qp->qp_num);
> +	clc->r0.rmb_rkey =
> +		htonl(conn->rmb_desc->mr[link->link_idx]->rkey);
> +	clc->r0.rmbe_idx = 1; /* for now: 1 RMB = 1 RMBE */
> +	clc->r0.rmbe_alert_token = htonl(conn->alert_token_local);
> +	switch (clc->hdr.type) {
> +	case SMC_CLC_ACCEPT:
> +		clc->r0.qp_mtu = link->path_mtu;
> +		break;
> +	case SMC_CLC_CONFIRM:
> +		clc->r0.qp_mtu = min(link->path_mtu, link->peer_mtu);
> +		break;
> +	}
> +	clc->r0.rmbe_size = conn->rmbe_size_comp;
> +	clc->r0.rmb_dma_addr = conn->rmb_desc->is_vm ?
> +		cpu_to_be64((uintptr_t)conn->rmb_desc->cpu_addr) :
> +		cpu_to_be64((u64)sg_dma_address
> +			    (conn->rmb_desc->sgt[link->link_idx].sgl));
> +	hton24(clc->r0.psn, link->psn_initial);
> +	if (version == SMC_V1) {
> +		clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
> +	} else {
> +		if (eid && eid[0])
> +			memcpy(clc_v2->r1.eid, eid, SMC_MAX_EID_LEN);
> +		len = SMCR_CLC_ACCEPT_CONFIRM_LEN_V2;
> +		if (first_contact) {
> +			*fce_len = smc_clc_fill_fce_v2x(fce_v2x, ini);
> +			len += *fce_len;
> +			fce_v2x->fce_v2_base.v2_direct =
> +				!link->lgr->uses_gateway;
> +			if (clc->hdr.type == SMC_CLC_CONFIRM) {
> +				memset(gle, 0, sizeof(*gle));
> +				gle->gid_cnt = ini->smcrv2.gidlist.len;
> +				len += sizeof(*gle);
> +				len += gle->gid_cnt * sizeof(gle->gid[0]);
> +			}
> +		}
> +		clc_v2->hdr.length = htons(len);
> +	}
> +	memcpy(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
> +}
> +
>  /* build and send CLC CONFIRM / ACCEPT message */
>  static int smc_clc_send_confirm_accept(struct smc_sock *smc,
>  				       struct smc_clc_msg_accept_confirm_v2 *clc_v2,
> @@ -1006,11 +1111,10 @@ static int smc_clc_send_confirm_accept(struct smc_sock *smc,
>  {
>  	struct smc_clc_first_contact_ext_v2x fce_v2x;
>  	struct smc_connection *conn = &smc->conn;
> -	struct smcd_dev *smcd = conn->lgr->smcd;
>  	struct smc_clc_msg_accept_confirm *clc;
>  	struct smc_clc_fce_gid_ext gle;
>  	struct smc_clc_msg_trail trl;
> -	int i, len, fce_len;
> +	int i, fce_len;
>  	struct kvec vec[5];
>  	struct msghdr msg;
>  
> @@ -1019,86 +1123,14 @@ static int smc_clc_send_confirm_accept(struct smc_sock *smc,
>  	clc->hdr.version = version;	/* SMC version */
>  	if (first_contact)
>  		clc->hdr.typev2 |= SMC_FIRST_CONTACT_MASK;
> -	if (conn->lgr->is_smcd) {
> -		/* SMC-D specific settings */
> -		memcpy(clc->hdr.eyecatcher, SMCD_EYECATCHER,
> -		       sizeof(SMCD_EYECATCHER));
> -		clc->hdr.typev1 = SMC_TYPE_D;
> -		clc->d0.gid = htonll(smcd->ops->get_local_gid(smcd));
> -		clc->d0.token = htonll(conn->rmb_desc->token);
> -		clc->d0.dmbe_size = conn->rmbe_size_comp;
> -		clc->d0.dmbe_idx = 0;
> -		memcpy(&clc->d0.linkid, conn->lgr->id, SMC_LGR_ID_SIZE);
> -		if (version == SMC_V1) {
> -			clc->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
> -		} else {
> -			clc_v2->d1.chid = htons(smc_ism_get_chid(smcd));
> -			if (eid && eid[0])
> -				memcpy(clc_v2->d1.eid, eid, SMC_MAX_EID_LEN);
> -			len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2;
> -			if (first_contact) {
> -				fce_len = smc_clc_fill_fce_v2x(&fce_v2x, ini);
> -				len += fce_len;
> -			}
> -			clc_v2->hdr.length = htons(len);
> -		}
> -		memcpy(trl.eyecatcher, SMCD_EYECATCHER,
> -		       sizeof(SMCD_EYECATCHER));
> -	} else {
> -		struct smc_link *link = conn->lnk;
> -
> -		/* SMC-R specific settings */
> -		memcpy(clc->hdr.eyecatcher, SMC_EYECATCHER,
> -		       sizeof(SMC_EYECATCHER));
> -		clc->hdr.typev1 = SMC_TYPE_R;
> -		clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
> -		memcpy(clc->r0.lcl.id_for_peer, local_systemid,
> -		       sizeof(local_systemid));
> -		memcpy(&clc->r0.lcl.gid, link->gid, SMC_GID_SIZE);
> -		memcpy(&clc->r0.lcl.mac, &link->smcibdev->mac[link->ibport - 1],
> -		       ETH_ALEN);
> -		hton24(clc->r0.qpn, link->roce_qp->qp_num);
> -		clc->r0.rmb_rkey =
> -			htonl(conn->rmb_desc->mr[link->link_idx]->rkey);
> -		clc->r0.rmbe_idx = 1; /* for now: 1 RMB = 1 RMBE */
> -		clc->r0.rmbe_alert_token = htonl(conn->alert_token_local);
> -		switch (clc->hdr.type) {
> -		case SMC_CLC_ACCEPT:
> -			clc->r0.qp_mtu = link->path_mtu;
> -			break;
> -		case SMC_CLC_CONFIRM:
> -			clc->r0.qp_mtu = min(link->path_mtu, link->peer_mtu);
> -			break;
> -		}
> -		clc->r0.rmbe_size = conn->rmbe_size_comp;
> -		clc->r0.rmb_dma_addr = conn->rmb_desc->is_vm ?
> -			cpu_to_be64((uintptr_t)conn->rmb_desc->cpu_addr) :
> -			cpu_to_be64((u64)sg_dma_address
> -				    (conn->rmb_desc->sgt[link->link_idx].sgl));
> -		hton24(clc->r0.psn, link->psn_initial);
> -		if (version == SMC_V1) {
> -			clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
> -		} else {
> -			if (eid && eid[0])
> -				memcpy(clc_v2->r1.eid, eid, SMC_MAX_EID_LEN);
> -			len = SMCR_CLC_ACCEPT_CONFIRM_LEN_V2;
> -			if (first_contact) {
> -				fce_len = smc_clc_fill_fce_v2x(&fce_v2x, ini);
> -				len += fce_len;
> -				fce_v2x.fce_v2_base.v2_direct =
> -					!link->lgr->uses_gateway;
> -				if (clc->hdr.type == SMC_CLC_CONFIRM) {
> -					memset(&gle, 0, sizeof(gle));
> -					gle.gid_cnt = ini->smcrv2.gidlist.len;
> -					len += sizeof(gle);
> -					len += gle.gid_cnt * sizeof(gle.gid[0]);
> -				}
> -			}
> -			clc_v2->hdr.length = htons(len);
> -		}
> -		memcpy(trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
> -	}
> -
> +	if (conn->lgr->is_smcd)
> +		smcd_clc_prep_confirm_accept(conn, clc_v2, first_contact,
> +					     version, eid, ini, &fce_len,
> +					     &fce_v2x, &trl);
> +	else
> +		smcr_clc_prep_confirm_accept(conn, clc_v2, first_contact,
> +					     version, eid, ini, &fce_len,
> +					     &fce_v2x, &gle, &trl);
>  	memset(&msg, 0, sizeof(msg));
>  	i = 0;
>  	vec[i].iov_base = clc_v2;

Re: [PATCH net-next v5 2/9] net/smc: introduce sub-functions for smc_clc_send_confirm_accept()

[Wen Gu]

On 2023/12/11 18:43, Alexandra Winter wrote:
> 
> 
> On 08.12.23 08:40, Wen Gu wrote:
>> There is a large if-else block in smc_clc_send_confirm_accept() and it
>> is better to split it into two sub-functions.
>>
>> Suggested-by: Alexandra Winter <wintera@linux.ibm.com>
>> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
>> ---
> 
> Thank you very much Wen Gu for improving the codebase.
> 
I'm glad I could help.

> 
>>   net/smc/smc_clc.c | 196 +++++++++++++++++++++++++++++++-----------------------
>>   1 file changed, 114 insertions(+), 82 deletions(-)
>>
>> diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
>> index 0fcb035..52b4ea9 100644
>> --- a/net/smc/smc_clc.c
>> +++ b/net/smc/smc_clc.c
>> @@ -998,6 +998,111 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
>>   	return reason_code;
>>   }
>>   
>> +static void smcd_clc_prep_confirm_accept(struct smc_connection *conn,
>> +				struct smc_clc_msg_accept_confirm_v2 *clc_v2,
>> +				int first_contact, u8 version,
>> +				u8 *eid, struct smc_init_info *ini,
>> +				int *fce_len,
>> +				struct smc_clc_first_contact_ext_v2x *fce_v2x,
>> +				struct smc_clc_msg_trail *trl)
>> +{
>> +	struct smcd_dev *smcd = conn->lgr->smcd;
>> +	struct smc_clc_msg_accept_confirm *clc;
>> +	int len;
>> +
>> +	/* SMC-D specific settings */
>> +	clc = (struct smc_clc_msg_accept_confirm *)clc_v2;
> 
> Why is this cast neccessary? (Here as well as in smcr_clc_prep_confirm_accept
> and in smc_clc_send_confirm_accept)
> smc_clc_msg_accept_confirm_v2 has hdr and d0 as well.

I think the cast is to imply that v2 is an expansion of v1, or v1 is the base of v2.
So here using clc(v1) reperesents their common set.

If we use smc_clc_msg_accept_confirm_v2 for all, I think readers may be tempted to
check whether the hdr and d0 in 'smc_clc_msg_accept_confirm_v2' are also applicable to v1.

And there are settings below that are specific for v1. It may be confusing if we
change it like this:

if (version == SMC_V1) {
	clc_v2->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
} else {


> 
> IMO, it would be a nice seperate patch to get rid of the 2 type defs for
> smc_clc_msg_accept_confirm and smc_clc_msg_accept_confirm_v2
> and all the related casting anyhow.
> 

Do you mean to define only smc_clc_msg_accept_confirm_v2 or define with the name
of smc_clc_msg_accept_confirm but the contents of smc_clc_msg_accept_confirm_v2?

I have a different opinion on this, since I think the smc_clc_msg_accept_confirm
and smc_clc_msg_accept_confirm_v2 clearly shows the difference between v1 and
v2 messages and remind people what is currently working on. So I perfer to keep them.
Am I missing something?

> 
> 
>> +	memcpy(clc->hdr.eyecatcher, SMCD_EYECATCHER,
>> +	       sizeof(SMCD_EYECATCHER));
>> +	clc->hdr.typev1 = SMC_TYPE_D;
>> +	clc->d0.gid = htonll(smcd->ops->get_local_gid(smcd));
>> +	clc->d0.token = htonll(conn->rmb_desc->token);
>> +	clc->d0.dmbe_size = conn->rmbe_size_comp;
>> +	clc->d0.dmbe_idx = 0;
>> +	memcpy(&clc->d0.linkid, conn->lgr->id, SMC_LGR_ID_SIZE);
>> +	if (version == SMC_V1) {
>> +		clc->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
>> +	} else {
>> +		clc_v2->d1.chid = htons(smc_ism_get_chid(smcd));
>> +		if (eid && eid[0])
>> +			memcpy(clc_v2->d1.eid, eid, SMC_MAX_EID_LEN);
>> +		len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2;
>> +		if (first_contact) {
>> +			*fce_len = smc_clc_fill_fce_v2x(fce_v2x, ini);
>> +			len += *fce_len;
>> +		}
>> +		clc_v2->hdr.length = htons(len);
>> +	}
>> +	memcpy(trl->eyecatcher, SMCD_EYECATCHER,
>> +	       sizeof(SMCD_EYECATCHER));
>> +}
>> +
>> +static void smcr_clc_prep_confirm_accept(struct smc_connection *conn,
>> +				struct smc_clc_msg_accept_confirm_v2 *clc_v2,
>> +				int first_contact, u8 version,
>> +				u8 *eid, struct smc_init_info *ini,
>> +				int *fce_len,
>> +				struct smc_clc_first_contact_ext_v2x *fce_v2x,
>> +				struct smc_clc_fce_gid_ext *gle,
>> +				struct smc_clc_msg_trail *trl)
>> +{
>> +	struct smc_clc_msg_accept_confirm *clc;
>> +	struct smc_link *link = conn->lnk;
>> +	int len;
>> +
>> +	/* SMC-R specific settings */
>> +	clc = (struct smc_clc_msg_accept_confirm *)clc_v2;
> 
> Why is this cast neccessary?
> smc_clc_msg_accept_confirm_v2 has hdr and r0 as well.
> 
Similar thought as SMCD.

>> +	memcpy(clc->hdr.eyecatcher, SMC_EYECATCHER,
>> +	       sizeof(SMC_EYECATCHER));
>> +	clc->hdr.typev1 = SMC_TYPE_R;
>> +	clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
> 
> ^^ this is overwritten below, so no need to set it here.
> 

Good catch! It will be removed. Thank you.

<...>

Re: [PATCH net-next v5 2/9] net/smc: introduce sub-functions for smc_clc_send_confirm_accept()

[Alexandra Winter]

On 11.12.23 13:15, Wen Gu wrote:
>>> +    clc = (struct smc_clc_msg_accept_confirm *)clc_v2;
>>
>> Why is this cast neccessary? (Here as well as in smcr_clc_prep_confirm_accept
>> and in smc_clc_send_confirm_accept)
>> smc_clc_msg_accept_confirm_v2 has hdr and d0 as well.
> 
> I think the cast is to imply that v2 is an expansion of v1, or v1 is the base of v2.
> So here using clc(v1) reperesents their common set.
> 
> If we use smc_clc_msg_accept_confirm_v2 for all, I think readers may be tempted to
> check whether the hdr and d0 in 'smc_clc_msg_accept_confirm_v2' are also applicable to v1.
> 
> And there are settings below that are specific for v1. It may be confusing if we
> change it like this:
> 
> if (version == SMC_V1) {
>     clc_v2->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
> } else {
> 
> 
>>
>> IMO, it would be a nice seperate patch to get rid of the 2 type defs for
>> smc_clc_msg_accept_confirm and smc_clc_msg_accept_confirm_v2
>> and all the related casting anyhow.
>>
> 
> Do you mean to define only smc_clc_msg_accept_confirm_v2 or define with the name
> of smc_clc_msg_accept_confirm but the contents of smc_clc_msg_accept_confirm_v2?
> 
> I have a different opinion on this, since I think the smc_clc_msg_accept_confirm
> and smc_clc_msg_accept_confirm_v2 clearly shows the difference between v1 and
> v2 messages and remind people what is currently working on. So I perfer to keep them.
> Am I missing something?
> 


This is a discussion about coding style, readability and maintainability (avoid future errors).
And the code works today and the rest is opinions. That said, let me list some arguments why
I don't like the casts.

Casts in general break the type checking of the compiler.

In some places e.g. clc.d0 points to struct smc_clc_msg_accept_confirm in other
places it points to struct smc_clc_msg_accept_confirm_v2.
This makes it hard to find all places where e.g. d0 is altered. (e.g. with an IDE).

You say: "smc_clc_msg_accept_confirm
> and smc_clc_msg_accept_confirm_v2 clearly shows the difference between v1 and
> v2 messages"
But that is not even the case in the code that this patch changes:
In smcd_clc_prep_confirm_accept() you pass a struct smc_clc_msg_accept_confirm_v2
cast it to v1 (even in the v2 case) and then use the v1 layout for the common fields and
the v1-only fields. So I don't think that helps very much.

The v2 messages were explicitely defined for compatibility. i.e.
all v1 fields are still available. It would be good to see that in the code as well.
With 2 differnet structs you don't emphasize that.

With future changes somebody could easily make a mistake that the 2 structures don't 
have the same size anymore. And then the casting can lead to out-of-bound error that
are hard to find.

We want v2 to be the usual case and v1 to be the exception for backwards compatibility.
FOr historic reasons, the code looks as if v2 is the exception. I'd rather point out the 
remaining v1 cases.



I could envision something like:

struct smc_clc_msg_accept_confirm {	/* clc accept / confirm message */
	struct smc_clc_msg_hdr hdr;
	union {
		struct { /* SMC-R */
			struct smcr_clc_msg_accept_confirm r0;
			/* v2 only, reserved and ignored in v1: */
			u8 eid[SMC_MAX_EID_LEN];
			u8 reserved6[8];
		} r1;
		struct { /* SMC-D */
			struct smcd_clc_msg_accept_confirm_common d0;
			/* v2 only, reserved and ignored in v1: */
			__be16 chid;
			u8 eid[SMC_MAX_EID_LEN];
			__be64 gid_ext;
		} __packed d1;
	};
};

And then only use this one structure.

Re: [PATCH net-next v5 2/9] net/smc: introduce sub-functions for smc_clc_send_confirm_accept()

[Wen Gu]

On 2023/12/11 21:35, Alexandra Winter wrote:
> 
> 
> On 11.12.23 13:15, Wen Gu wrote:
>>>> +    clc = (struct smc_clc_msg_accept_confirm *)clc_v2;
>>>
>>> Why is this cast neccessary? (Here as well as in smcr_clc_prep_confirm_accept
>>> and in smc_clc_send_confirm_accept)
>>> smc_clc_msg_accept_confirm_v2 has hdr and d0 as well.
>>
>> I think the cast is to imply that v2 is an expansion of v1, or v1 is the base of v2.
>> So here using clc(v1) reperesents their common set.
>>
>> If we use smc_clc_msg_accept_confirm_v2 for all, I think readers may be tempted to
>> check whether the hdr and d0 in 'smc_clc_msg_accept_confirm_v2' are also applicable to v1.
>>
>> And there are settings below that are specific for v1. It may be confusing if we
>> change it like this:
>>
>> if (version == SMC_V1) {
>>      clc_v2->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
>> } else {
>>
>>
>>>
>>> IMO, it would be a nice seperate patch to get rid of the 2 type defs for
>>> smc_clc_msg_accept_confirm and smc_clc_msg_accept_confirm_v2
>>> and all the related casting anyhow.
>>>
>>
>> Do you mean to define only smc_clc_msg_accept_confirm_v2 or define with the name
>> of smc_clc_msg_accept_confirm but the contents of smc_clc_msg_accept_confirm_v2?
>>
>> I have a different opinion on this, since I think the smc_clc_msg_accept_confirm
>> and smc_clc_msg_accept_confirm_v2 clearly shows the difference between v1 and
>> v2 messages and remind people what is currently working on. So I perfer to keep them.
>> Am I missing something?
>>
> 
> 
> This is a discussion about coding style, readability and maintainability (avoid future errors).
> And the code works today and the rest is opinions. That said, let me list some arguments why
> I don't like the casts.
> 
> Casts in general break the type checking of the compiler.
> 
> In some places e.g. clc.d0 points to struct smc_clc_msg_accept_confirm in other
> places it points to struct smc_clc_msg_accept_confirm_v2.
> This makes it hard to find all places where e.g. d0 is altered. (e.g. with an IDE).
> 
> You say: "smc_clc_msg_accept_confirm
>> and smc_clc_msg_accept_confirm_v2 clearly shows the difference between v1 and
>> v2 messages"
> But that is not even the case in the code that this patch changes:
> In smcd_clc_prep_confirm_accept() you pass a struct smc_clc_msg_accept_confirm_v2
> cast it to v1 (even in the v2 case) and then use the v1 layout for the common fields and
> the v1-only fields. So I don't think that helps very much.
> 
> The v2 messages were explicitely defined for compatibility. i.e.
> all v1 fields are still available. It would be good to see that in the code as well.
> With 2 differnet structs you don't emphasize that.
> 
> With future changes somebody could easily make a mistake that the 2 structures don't
> have the same size anymore. And then the casting can lead to out-of-bound error that
> are hard to find.
> 
> We want v2 to be the usual case and v1 to be the exception for backwards compatibility.
> FOr historic reasons, the code looks as if v2 is the exception. I'd rather point out the
> remaining v1 cases.
> 
> 
> 
> I could envision something like:
> 
> struct smc_clc_msg_accept_confirm {	/* clc accept / confirm message */
> 	struct smc_clc_msg_hdr hdr;
> 	union {
> 		struct { /* SMC-R */
> 			struct smcr_clc_msg_accept_confirm r0;
> 			/* v2 only, reserved and ignored in v1: */
> 			u8 eid[SMC_MAX_EID_LEN];
> 			u8 reserved6[8];
> 		} r1;
> 		struct { /* SMC-D */
> 			struct smcd_clc_msg_accept_confirm_common d0;
> 			/* v2 only, reserved and ignored in v1: */
> 			__be16 chid;
> 			u8 eid[SMC_MAX_EID_LEN];
> 			__be64 gid_ext;
> 		} __packed d1;
> 	};
> };
> 
> And then only use this one structure.
> 

Thank you Sandy for the detailed explanation.

What I considered, as mentioned above, is that if the two are combined,
it may be difficult to distinguish according to the name what situation
I am in, v1 or v2?

But I do agree with your concern about the potential errors that caused
by future divergence of the two struct if they are defined separately.

I will try to combine them into one struct in a seperate patch.

Thank you.

[PATCH net-next v5 3/9] net/smc: support SMCv2.x supplemental features negotiation

[Wen Gu]

This patch adds SMCv2.x supplemental features negotiation. Supported
SMCv2.x supplemental features are represented by feature_mask in FCE
field. The negotiation process is as follows.

 Server                                        Client
            Proposal(features(c-mask bits))
      <-----------------------------------------
            Accept(features(s-mask bits))
      ----------------------------------------->
           Confirm(features(s&c-mask bits))
      <-----------------------------------------

Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
---
 net/smc/smc.h      |  4 ++++
 net/smc/smc_clc.c  |  7 +++++++
 net/smc/smc_clc.h  | 14 ++++++++++----
 net/smc/smc_core.h |  1 +
 4 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/net/smc/smc.h b/net/smc/smc.h
index cd51261..95f56c7 100644
--- a/net/smc/smc.h
+++ b/net/smc/smc.h
@@ -58,6 +58,10 @@ enum smc_state {		/* possible states of an SMC socket */
 	SMC_PROCESSABORT	= 27,
 };
 
+#define SMC_FEATURE_MASK	0	/* bitmask of
+					 * supported supplemental features
+					 */
+
 struct smc_link_group;
 
 struct smc_wr_rx_hdr {	/* common prefix part of LLC and CDC to demultiplex */
diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
index 52b4ea9..81e09d1 100644
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -438,6 +438,7 @@ static int smc_clc_fill_fce_v2x(struct smc_clc_first_contact_ext_v2x *fce_v2x,
 			fce_v2x->max_conns = ini->max_conns;
 			fce_v2x->max_links = ini->max_links;
 		}
+		fce_v2x->feature_mask = htons(ini->feature_mask);
 	}
 
 out:
@@ -908,6 +909,7 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
 		pclc_smcd->v2_ext_offset = htons(v2_ext_offset);
 		plen += sizeof(*v2_ext);
 
+		v2_ext->feature_mask = htons(SMC_FEATURE_MASK);
 		read_lock(&smc_clc_eid_table.lock);
 		v2_ext->hdr.eid_cnt = smc_clc_eid_table.ueid_cnt;
 		plen += smc_clc_eid_table.ueid_cnt * SMC_MAX_EID_LEN;
@@ -1214,6 +1216,7 @@ int smc_clc_srv_v2x_features_validate(struct smc_sock *smc,
 
 	ini->max_conns = SMC_CONN_PER_LGR_MAX;
 	ini->max_links = SMC_LINKS_ADD_LNK_MAX;
+	ini->feature_mask = SMC_FEATURE_MASK;
 
 	if ((!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) ||
 	    ini->release_nr < SMC_RELEASE_1)
@@ -1257,6 +1260,8 @@ int smc_clc_clnt_v2x_features_validate(struct smc_clc_first_contact_ext *fce,
 			return SMC_CLC_DECL_MAXLINKERR;
 		ini->max_links = fce_v2x->max_links;
 	}
+	/* common supplemental features of server and client */
+	ini->feature_mask = ntohs(fce_v2x->feature_mask) & SMC_FEATURE_MASK;
 
 	return 0;
 }
@@ -1287,6 +1292,8 @@ int smc_clc_v2x_features_confirm_check(struct smc_clc_msg_accept_confirm *cclc,
 		if (fce_v2x->max_links != ini->max_links)
 			return SMC_CLC_DECL_MAXLINKERR;
 	}
+	/* common supplemental features returned by client */
+	ini->feature_mask = ntohs(fce_v2x->feature_mask);
 
 	return 0;
 }
diff --git a/net/smc/smc_clc.h b/net/smc/smc_clc.h
index 1697b84..0112e7c 100644
--- a/net/smc/smc_clc.h
+++ b/net/smc/smc_clc.h
@@ -138,7 +138,8 @@ struct smc_clc_v2_extension {
 	u8 roce[16];		/* RoCEv2 GID */
 	u8 max_conns;
 	u8 max_links;
-	u8 reserved[14];
+	__be16 feature_mask;
+	u8 reserved[12];
 	u8 user_eids[][SMC_MAX_EID_LEN];
 };
 
@@ -240,9 +241,14 @@ struct smc_clc_first_contact_ext {
 
 struct smc_clc_first_contact_ext_v2x {
 	struct smc_clc_first_contact_ext fce_v2_base;
-	u8 max_conns; /* for SMC-R only */
-	u8 max_links; /* for SMC-R only */
-	u8 reserved3[2];
+	union {
+		struct {
+			u8 max_conns; /* for SMC-R only */
+			u8 max_links; /* for SMC-R only */
+		};
+		u8 reserved3[2];	/* for SMC-D only */
+	};
+	__be16 feature_mask;
 	__be32 vendor_exp_options;
 	u8 reserved4[8];
 } __packed;		/* format defined in
diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index 120027d..9f65678 100644
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -401,6 +401,7 @@ struct smc_init_info {
 	u8			max_links;
 	u8			first_contact_peer;
 	u8			first_contact_local;
+	u16			feature_mask;
 	unsigned short		vlan_id;
 	u32			rc;
 	u8			negotiated_eid[SMC_MAX_EID_LEN];
-- 
1.8.3.1

[PATCH net-next v5 4/9] net/smc: introduce virtual ISM device support feature

[Wen Gu]

This introduces virtual ISM device support feature to SMCv2.1 as the
first supplemental feature.

Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
---
 net/smc/smc.h | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/net/smc/smc.h b/net/smc/smc.h
index 95f56c7..0dc722b 100644
--- a/net/smc/smc.h
+++ b/net/smc/smc.h
@@ -58,9 +58,12 @@ enum smc_state {		/* possible states of an SMC socket */
 	SMC_PROCESSABORT	= 27,
 };
 
-#define SMC_FEATURE_MASK	0	/* bitmask of
-					 * supported supplemental features
-					 */
+enum smc_supplemental_features {
+	SMC_SPF_VIRT_ISM_DEV	= 0,
+};
+
+#define SMC_FEATURE_MASK \
+	(BIT(SMC_SPF_VIRT_ISM_DEV))
 
 struct smc_link_group;
 
-- 
1.8.3.1

[PATCH net-next v5 5/9] net/smc: define a reserved CHID range for virtual ISM devices

[Wen Gu]

According to virtual ISM support feature defined by SMCv2.1, CHIDs in
the range 0xFF00 to 0xFFFF are reserved for use by virtual ISM devices.

And two helpers are introduced to distinguish virtual ISM devices from
the existing platform firmware ISM devices.

Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
---
 net/smc/smc_ism.h | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/net/smc/smc_ism.h b/net/smc/smc_ism.h
index 832b2f4..d1228a6 100644
--- a/net/smc/smc_ism.h
+++ b/net/smc/smc_ism.h
@@ -15,6 +15,8 @@
 
 #include "smc.h"
 
+#define SMC_VIRTUAL_ISM_CHID_MASK	0xFF00
+
 struct smcd_dev_list {	/* List of SMCD devices */
 	struct list_head list;
 	struct mutex mutex;	/* Protects list of devices */
@@ -56,4 +58,22 @@ static inline int smc_ism_write(struct smcd_dev *smcd, u64 dmb_tok,
 	return rc < 0 ? rc : 0;
 }
 
+static inline bool __smc_ism_is_virtual(u16 chid)
+{
+	/* CHIDs in range of 0xFF00 to 0xFFFF are reserved
+	 * for virtual ISM device.
+	 *
+	 * loopback-ism:	0xFFFF
+	 * virtio-ism:		0xFF00 ~ 0xFFFE
+	 */
+	return ((chid & 0xFF00) == 0xFF00);
+}
+
+static inline bool smc_ism_is_virtual(struct smcd_dev *smcd)
+{
+	u16 chid = smcd->ops->get_chid(smcd);
+
+	return __smc_ism_is_virtual(chid);
+}
+
 #endif
-- 
1.8.3.1

Re: [PATCH net-next v5 5/9] net/smc: define a reserved CHID range for virtual ISM devices

[Alexandra Winter]

On 08.12.23 08:40, Wen Gu wrote:
> According to virtual ISM support feature defined by SMCv2.1, CHIDs in
> the range 0xFF00 to 0xFFFF are reserved for use by virtual ISM devices.
> 
> And two helpers are introduced to distinguish virtual ISM devices from
> the existing platform firmware ISM devices.
> 
> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
> ---

I've sent you a Reviewed-by for v3 of this patch. Did you lose it?

Re: [PATCH net-next v5 5/9] net/smc: define a reserved CHID range for virtual ISM devices

[Wen Gu]

On 2023/12/11 16:24, Alexandra Winter wrote:
> 
> 
> On 08.12.23 08:40, Wen Gu wrote:
>> According to virtual ISM support feature defined by SMCv2.1, CHIDs in
>> the range 0xFF00 to 0xFFFF are reserved for use by virtual ISM devices.
>>
>> And two helpers are introduced to distinguish virtual ISM devices from
>> the existing platform firmware ISM devices.
>>
>> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
>> ---
> 
> I've sent you a Reviewed-by for v3 of this patch. Did you lose it?

Sorry! I missed it when formating the patches.
I will add your and Wenjia's Reviewed-by to the unmodified patches, thank you!
New version coming soon.

[PATCH net-next v5 6/9] net/smc: compatible with 128-bits extended GID of virtual ISM device

[Wen Gu]

According to virtual ISM support feature defined by SMCv2.1, GIDs of
virtual ISM device are UUIDs defined by RFC4122, which are 128-bits
long. So some adaptation work is required. And note that the GIDs of
existing platform firmware ISM devices still remain 64-bits long.

Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
---
 drivers/s390/net/ism_drv.c | 19 +++++++------
 include/net/smc.h          | 15 +++++++----
 net/smc/af_smc.c           | 66 +++++++++++++++++++++++++++++++++++++---------
 net/smc/smc.h              |  3 ---
 net/smc/smc_clc.c          | 43 ++++++++++++++++++++++--------
 net/smc/smc_clc.h          | 12 ++++++---
 net/smc/smc_core.c         | 31 +++++++++++++++-------
 net/smc/smc_core.h         | 17 ++++++++----
 net/smc/smc_diag.c         |  7 +++--
 net/smc/smc_ism.c          | 17 +++++++-----
 net/smc/smc_ism.h          |  3 ++-
 net/smc/smc_pnet.c         |  4 +--
 12 files changed, 168 insertions(+), 69 deletions(-)

diff --git a/drivers/s390/net/ism_drv.c b/drivers/s390/net/ism_drv.c
index 81aabbf..34dd063 100644
--- a/drivers/s390/net/ism_drv.c
+++ b/drivers/s390/net/ism_drv.c
@@ -743,10 +743,10 @@ static int ism_query_rgid(struct ism_dev *ism, u64 rgid, u32 vid_valid,
 	return ism_cmd(ism, &cmd);
 }
 
-static int smcd_query_rgid(struct smcd_dev *smcd, u64 rgid, u32 vid_valid,
-			   u32 vid)
+static int smcd_query_rgid(struct smcd_dev *smcd, struct smcd_gid *rgid,
+			   u32 vid_valid, u32 vid)
 {
-	return ism_query_rgid(smcd->priv, rgid, vid_valid, vid);
+	return ism_query_rgid(smcd->priv, rgid->gid, vid_valid, vid);
 }
 
 static int smcd_register_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb,
@@ -797,10 +797,11 @@ static int ism_signal_ieq(struct ism_dev *ism, u64 rgid, u32 trigger_irq,
 	return ism_cmd(ism, &cmd);
 }
 
-static int smcd_signal_ieq(struct smcd_dev *smcd, u64 rgid, u32 trigger_irq,
-			   u32 event_code, u64 info)
+static int smcd_signal_ieq(struct smcd_dev *smcd, struct smcd_gid *rgid,
+			   u32 trigger_irq, u32 event_code, u64 info)
 {
-	return ism_signal_ieq(smcd->priv, rgid, trigger_irq, event_code, info);
+	return ism_signal_ieq(smcd->priv, rgid->gid,
+			      trigger_irq, event_code, info);
 }
 
 static int smcd_move(struct smcd_dev *smcd, u64 dmb_tok, unsigned int idx,
@@ -821,9 +822,11 @@ static u64 ism_get_local_gid(struct ism_dev *ism)
 	return ism->local_gid;
 }
 
-static u64 smcd_get_local_gid(struct smcd_dev *smcd)
+static void smcd_get_local_gid(struct smcd_dev *smcd,
+			       struct smcd_gid *smcd_gid)
 {
-	return ism_get_local_gid(smcd->priv);
+	smcd_gid->gid = ism_get_local_gid(smcd->priv);
+	smcd_gid->gid_ext = 0;
 }
 
 static u16 ism_get_chid(struct ism_dev *ism)
diff --git a/include/net/smc.h b/include/net/smc.h
index a002552..a0dc1187e 100644
--- a/include/net/smc.h
+++ b/include/net/smc.h
@@ -52,9 +52,14 @@ struct smcd_dmb {
 struct smcd_dev;
 struct ism_client;
 
+struct smcd_gid {
+	u64	gid;
+	u64	gid_ext;
+};
+
 struct smcd_ops {
-	int (*query_remote_gid)(struct smcd_dev *dev, u64 rgid, u32 vid_valid,
-				u32 vid);
+	int (*query_remote_gid)(struct smcd_dev *dev, struct smcd_gid *rgid,
+				u32 vid_valid, u32 vid);
 	int (*register_dmb)(struct smcd_dev *dev, struct smcd_dmb *dmb,
 			    struct ism_client *client);
 	int (*unregister_dmb)(struct smcd_dev *dev, struct smcd_dmb *dmb);
@@ -62,14 +67,14 @@ struct smcd_ops {
 	int (*del_vlan_id)(struct smcd_dev *dev, u64 vlan_id);
 	int (*set_vlan_required)(struct smcd_dev *dev);
 	int (*reset_vlan_required)(struct smcd_dev *dev);
-	int (*signal_event)(struct smcd_dev *dev, u64 rgid, u32 trigger_irq,
-			    u32 event_code, u64 info);
+	int (*signal_event)(struct smcd_dev *dev, struct smcd_gid *rgid,
+			    u32 trigger_irq, u32 event_code, u64 info);
 	int (*move_data)(struct smcd_dev *dev, u64 dmb_tok, unsigned int idx,
 			 bool sf, unsigned int offset, void *data,
 			 unsigned int size);
 	int (*supports_v2)(void);
 	u8* (*get_system_eid)(void);
-	u64 (*get_local_gid)(struct smcd_dev *dev);
+	void (*get_local_gid)(struct smcd_dev *dev, struct smcd_gid *gid);
 	u16 (*get_chid)(struct smcd_dev *dev);
 	struct device* (*get_dev)(struct smcd_dev *dev);
 };
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 7fc2f3c..9cdc974 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -1048,7 +1048,8 @@ static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
 {
 	int rc = SMC_CLC_DECL_NOSMCDDEV;
 	struct smcd_dev *smcd;
-	int i = 1;
+	int i = 1, entry = 1;
+	bool is_virtual;
 	u16 chid;
 
 	if (smcd_indicated(ini->smc_type_v1))
@@ -1060,14 +1061,23 @@ static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
 		chid = smc_ism_get_chid(smcd);
 		if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
 			continue;
+		is_virtual = __smc_ism_is_virtual(chid);
 		if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
 		    smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
+			if (is_virtual && entry == SMCD_CLC_MAX_V2_GID_ENTRIES)
+				/* It's the last GID-CHID entry left in CLC
+				 * Proposal SMC-Dv2 extension, but a virtual
+				 * ISM device will take two entries. So give
+				 * up it and try the next potential ISM device.
+				 */
+				continue;
 			ini->ism_dev[i] = smcd;
 			ini->ism_chid[i] = chid;
 			ini->is_smcd = true;
 			rc = 0;
 			i++;
-			if (i > SMC_MAX_ISM_DEVS)
+			entry = is_virtual ? entry + 2 : entry + 1;
+			if (entry > SMCD_CLC_MAX_V2_GID_ENTRIES)
 				break;
 		}
 	}
@@ -1414,8 +1424,13 @@ static int smc_connect_ism(struct smc_sock *smc,
 		rc = smc_v2_determine_accepted_chid(aclc_v2, ini);
 		if (rc)
 			return rc;
+
+		if (__smc_ism_is_virtual(ini->ism_chid[ini->ism_selected]))
+			ini->ism_peer_gid[ini->ism_selected].gid_ext =
+						ntohll(aclc_v2->d1.gid_ext);
+		/* for non-virtual ISM devices, peer gid_ext remains 0. */
 	}
-	ini->ism_peer_gid[ini->ism_selected] = ntohll(aclc->d0.gid);
+	ini->ism_peer_gid[ini->ism_selected].gid = ntohll(aclc->d0.gid);
 
 	/* there is only one lgr role for SMC-D; use server lock */
 	mutex_lock(&smc_server_lgr_pending);
@@ -2106,7 +2121,8 @@ static bool smc_is_already_selected(struct smcd_dev *smcd,
 
 /* check for ISM devices matching proposed ISM devices */
 static void smc_check_ism_v2_match(struct smc_init_info *ini,
-				   u16 proposed_chid, u64 proposed_gid,
+				   u16 proposed_chid,
+				   struct smcd_gid *proposed_gid,
 				   unsigned int *matches)
 {
 	struct smcd_dev *smcd;
@@ -2118,7 +2134,11 @@ static void smc_check_ism_v2_match(struct smc_init_info *ini,
 			continue;
 		if (smc_ism_get_chid(smcd) == proposed_chid &&
 		    !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
-			ini->ism_peer_gid[*matches] = proposed_gid;
+			ini->ism_peer_gid[*matches].gid = proposed_gid->gid;
+			if (__smc_ism_is_virtual(proposed_chid))
+				ini->ism_peer_gid[*matches].gid_ext =
+							proposed_gid->gid_ext;
+				/* non-virtual ISM's peer gid_ext remains 0. */
 			ini->ism_dev[*matches] = smcd;
 			(*matches)++;
 			break;
@@ -2140,9 +2160,11 @@ static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
 	struct smc_clc_v2_extension *smc_v2_ext;
 	struct smc_clc_msg_smcd *pclc_smcd;
 	unsigned int matches = 0;
+	struct smcd_gid smcd_gid;
 	u8 smcd_version;
 	u8 *eid = NULL;
 	int i, rc;
+	u16 chid;
 
 	if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
 		goto not_found;
@@ -2152,18 +2174,35 @@ static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
 	smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
 
 	mutex_lock(&smcd_dev_list.mutex);
-	if (pclc_smcd->ism.chid)
+	if (pclc_smcd->ism.chid) {
 		/* check for ISM device matching proposed native ISM device */
+		smcd_gid.gid = ntohll(pclc_smcd->ism.gid);
+		smcd_gid.gid_ext = 0;
 		smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
-				       ntohll(pclc_smcd->ism.gid), &matches);
-	for (i = 1; i <= smc_v2_ext->hdr.ism_gid_cnt; i++) {
+				       &smcd_gid, &matches);
+	}
+	for (i = 0; i < smc_v2_ext->hdr.ism_gid_cnt; i++) {
 		/* check for ISM devices matching proposed non-native ISM
 		 * devices
 		 */
-		smc_check_ism_v2_match(ini,
-				       ntohs(smcd_v2_ext->gidchid[i - 1].chid),
-				       ntohll(smcd_v2_ext->gidchid[i - 1].gid),
-				       &matches);
+		smcd_gid.gid = ntohll(smcd_v2_ext->gidchid[i].gid);
+		smcd_gid.gid_ext = 0;
+		chid = ntohs(smcd_v2_ext->gidchid[i].chid);
+		if (__smc_ism_is_virtual(chid)) {
+			if ((i + 1) == smc_v2_ext->hdr.ism_gid_cnt ||
+			    chid != ntohs(smcd_v2_ext->gidchid[i + 1].chid))
+				/* each virtual ISM device takes two GID-CHID
+				 * entries and CHID of the second entry repeats
+				 * that of the first entry.
+				 *
+				 * So check if the next GID-CHID entry exists
+				 * and both two entries' CHIDs are the same.
+				 */
+				continue;
+			smcd_gid.gid_ext =
+				ntohll(smcd_v2_ext->gidchid[++i].gid);
+		}
+		smc_check_ism_v2_match(ini, chid, &smcd_gid, &matches);
 	}
 	mutex_unlock(&smcd_dev_list.mutex);
 
@@ -2212,7 +2251,8 @@ static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
 	if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
 		goto not_found;
 	ini->is_smcd = true; /* prepare ISM check */
-	ini->ism_peer_gid[0] = ntohll(pclc_smcd->ism.gid);
+	ini->ism_peer_gid[0].gid = ntohll(pclc_smcd->ism.gid);
+	ini->ism_peer_gid[0].gid_ext = 0;
 	rc = smc_find_ism_device(new_smc, ini);
 	if (rc)
 		goto not_found;
diff --git a/net/smc/smc.h b/net/smc/smc.h
index 0dc722b..df64efd 100644
--- a/net/smc/smc.h
+++ b/net/smc/smc.h
@@ -29,9 +29,6 @@
 #define SMCPROTO_SMC		0	/* SMC protocol, IPv4 */
 #define SMCPROTO_SMC6		1	/* SMC protocol, IPv6 */
 
-#define SMC_MAX_ISM_DEVS	8	/* max # of proposed non-native ISM
-					 * devices
-					 */
 #define SMC_AUTOCORKING_DEFAULT_SIZE	0x10000	/* 64K by default */
 
 extern struct proto smc_proto;
diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
index 81e09d1..3604150 100644
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -884,11 +884,13 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
 		       ETH_ALEN);
 	}
 	if (smcd_indicated(ini->smc_type_v1)) {
+		struct smcd_gid smcd_gid;
+
 		/* add SMC-D specifics */
 		if (ini->ism_dev[0]) {
 			smcd = ini->ism_dev[0];
-			pclc_smcd->ism.gid =
-				htonll(smcd->ops->get_local_gid(smcd));
+			smcd->ops->get_local_gid(smcd, &smcd_gid);
+			pclc_smcd->ism.gid = htonll(smcd_gid.gid);
 			pclc_smcd->ism.chid =
 				htons(smc_ism_get_chid(ini->ism_dev[0]));
 		}
@@ -921,10 +923,11 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
 		read_unlock(&smc_clc_eid_table.lock);
 	}
 	if (smcd_indicated(ini->smc_type_v2)) {
+		struct smcd_gid smcd_gid;
 		u8 *eid = NULL;
+		int entry = 0;
 
 		v2_ext->hdr.flag.seid = smc_clc_eid_table.seid_enabled;
-		v2_ext->hdr.ism_gid_cnt = ini->ism_offered_cnt;
 		v2_ext->hdr.smcd_v2_ext_offset = htons(sizeof(*v2_ext) -
 				offsetofend(struct smc_clnt_opts_area_hdr,
 					    smcd_v2_ext_offset) +
@@ -936,14 +939,26 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
 		if (ini->ism_offered_cnt) {
 			for (i = 1; i <= ini->ism_offered_cnt; i++) {
 				smcd = ini->ism_dev[i];
-				gidchids[i - 1].gid =
-					htonll(smcd->ops->get_local_gid(smcd));
-				gidchids[i - 1].chid =
+				smcd->ops->get_local_gid(smcd, &smcd_gid);
+				gidchids[entry].chid =
 					htons(smc_ism_get_chid(ini->ism_dev[i]));
+				gidchids[entry].gid = htonll(smcd_gid.gid);
+				if (smc_ism_is_virtual(smcd)) {
+					/* a virtual ISM device takes two
+					 * entries. CHID of the second entry
+					 * repeats that of the first entry.
+					 */
+					gidchids[entry + 1].chid =
+						gidchids[entry].chid;
+					gidchids[entry + 1].gid =
+						htonll(smcd_gid.gid_ext);
+					entry++;
+				}
+				entry++;
 			}
-			plen += ini->ism_offered_cnt *
-				sizeof(struct smc_clc_smcd_gid_chid);
+			plen += entry * sizeof(struct smc_clc_smcd_gid_chid);
 		}
+		v2_ext->hdr.ism_gid_cnt = entry;
 	}
 	if (smcr_indicated(ini->smc_type_v2)) {
 		memcpy(v2_ext->roce, ini->smcrv2.ib_gid_v2, SMC_GID_SIZE);
@@ -979,7 +994,7 @@ int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
 			vec[i++].iov_len = sizeof(*smcd_v2_ext);
 			if (ini->ism_offered_cnt) {
 				vec[i].iov_base = gidchids;
-				vec[i++].iov_len = ini->ism_offered_cnt *
+				vec[i++].iov_len = v2_ext->hdr.ism_gid_cnt *
 					sizeof(struct smc_clc_smcd_gid_chid);
 			}
 		}
@@ -1010,14 +1025,17 @@ static void smcd_clc_prep_confirm_accept(struct smc_connection *conn,
 {
 	struct smcd_dev *smcd = conn->lgr->smcd;
 	struct smc_clc_msg_accept_confirm *clc;
+	struct smcd_gid smcd_gid;
+	u16 chid;
 	int len;
 
 	/* SMC-D specific settings */
 	clc = (struct smc_clc_msg_accept_confirm *)clc_v2;
 	memcpy(clc->hdr.eyecatcher, SMCD_EYECATCHER,
 	       sizeof(SMCD_EYECATCHER));
+	smcd->ops->get_local_gid(smcd, &smcd_gid);
 	clc->hdr.typev1 = SMC_TYPE_D;
-	clc->d0.gid = htonll(smcd->ops->get_local_gid(smcd));
+	clc->d0.gid = htonll(smcd_gid.gid);
 	clc->d0.token = htonll(conn->rmb_desc->token);
 	clc->d0.dmbe_size = conn->rmbe_size_comp;
 	clc->d0.dmbe_idx = 0;
@@ -1025,9 +1043,12 @@ static void smcd_clc_prep_confirm_accept(struct smc_connection *conn,
 	if (version == SMC_V1) {
 		clc->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
 	} else {
-		clc_v2->d1.chid = htons(smc_ism_get_chid(smcd));
+		chid = smc_ism_get_chid(smcd);
+		clc_v2->d1.chid = htons(chid);
 		if (eid && eid[0])
 			memcpy(clc_v2->d1.eid, eid, SMC_MAX_EID_LEN);
+		if (__smc_ism_is_virtual(chid))
+			clc_v2->d1.gid_ext = htonll(smcd_gid.gid_ext);
 		len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2;
 		if (first_contact) {
 			*fce_len = smc_clc_fill_fce_v2x(fce_v2x, ini);
diff --git a/net/smc/smc_clc.h b/net/smc/smc_clc.h
index 0112e7c..80952cd 100644
--- a/net/smc/smc_clc.h
+++ b/net/smc/smc_clc.h
@@ -172,6 +172,11 @@ struct smc_clc_msg_proposal {	/* clc proposal message sent by Linux */
 
 #define SMC_CLC_MAX_V6_PREFIX		8
 #define SMC_CLC_MAX_UEID		8
+#define SMCD_CLC_MAX_V2_GID_ENTRIES	8 /* max # of CHID-GID entries in CLC
+					   * proposal SMC-Dv2 extension.
+					   * each ISM device takes one entry and
+					   * each virtual ISM takes two entries.
+					   */
 
 struct smc_clc_msg_proposal_area {
 	struct smc_clc_msg_proposal		pclc_base;
@@ -181,7 +186,8 @@ struct smc_clc_msg_proposal_area {
 	struct smc_clc_v2_extension		pclc_v2_ext;
 	u8			user_eids[SMC_CLC_MAX_UEID][SMC_MAX_EID_LEN];
 	struct smc_clc_smcd_v2_extension	pclc_smcd_v2_ext;
-	struct smc_clc_smcd_gid_chid		pclc_gidchids[SMC_MAX_ISM_DEVS];
+	struct smc_clc_smcd_gid_chid
+				pclc_gidchids[SMCD_CLC_MAX_V2_GID_ENTRIES];
 	struct smc_clc_msg_trail		pclc_trl;
 };
 
@@ -285,8 +291,8 @@ struct smc_clc_msg_accept_confirm_v2 {	/* clc accept / confirm message */
 			struct smcd_clc_msg_accept_confirm_common d0;
 			__be16 chid;
 			u8 eid[SMC_MAX_EID_LEN];
-			u8 reserved5[8];
-		} d1;
+			__be64 gid_ext;
+		} __packed d1;
 	};
 };
 
diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index d520ee6..672eff0 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -506,6 +506,7 @@ static int smc_nl_fill_smcd_lgr(struct smc_link_group *lgr,
 {
 	char smc_pnet[SMC_MAX_PNETID_LEN + 1];
 	struct smcd_dev *smcd = lgr->smcd;
+	struct smcd_gid smcd_gid;
 	struct nlattr *attrs;
 	void *nlh;
 
@@ -521,11 +522,11 @@ static int smc_nl_fill_smcd_lgr(struct smc_link_group *lgr,
 
 	if (nla_put_u32(skb, SMC_NLA_LGR_D_ID, *((u32 *)&lgr->id)))
 		goto errattr;
+	smcd->ops->get_local_gid(smcd, &smcd_gid);
 	if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_GID,
-			      smcd->ops->get_local_gid(smcd),
-				  SMC_NLA_LGR_D_PAD))
+			      smcd_gid.gid, SMC_NLA_LGR_D_PAD))
 		goto errattr;
-	if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_GID, lgr->peer_gid,
+	if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_GID, lgr->peer_gid.gid,
 			      SMC_NLA_LGR_D_PAD))
 		goto errattr;
 	if (nla_put_u8(skb, SMC_NLA_LGR_D_VLAN_ID, lgr->vlan_id))
@@ -876,7 +877,10 @@ static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
 		/* SMC-D specific settings */
 		smcd = ini->ism_dev[ini->ism_selected];
 		get_device(smcd->ops->get_dev(smcd));
-		lgr->peer_gid = ini->ism_peer_gid[ini->ism_selected];
+		lgr->peer_gid.gid =
+			ini->ism_peer_gid[ini->ism_selected].gid;
+		lgr->peer_gid.gid_ext =
+			ini->ism_peer_gid[ini->ism_selected].gid_ext;
 		lgr->smcd = ini->ism_dev[ini->ism_selected];
 		lgr_list = &ini->ism_dev[ini->ism_selected]->lgr_list;
 		lgr_lock = &lgr->smcd->lgr_lock;
@@ -1514,7 +1518,8 @@ void smc_lgr_terminate_sched(struct smc_link_group *lgr)
 }
 
 /* Called when peer lgr shutdown (regularly or abnormally) is received */
-void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan)
+void smc_smcd_terminate(struct smcd_dev *dev, struct smcd_gid *peer_gid,
+			unsigned short vlan)
 {
 	struct smc_link_group *lgr, *l;
 	LIST_HEAD(lgr_free_list);
@@ -1522,9 +1527,12 @@ void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan)
 	/* 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) &&
+		if ((!peer_gid->gid ||
+		     (lgr->peer_gid.gid == peer_gid->gid &&
+		      !smc_ism_is_virtual(dev) ? 1 :
+		      lgr->peer_gid.gid_ext == peer_gid->gid_ext)) &&
 		    (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
-			if (peer_gid) /* peer triggered termination */
+			if (peer_gid->gid) /* peer triggered termination */
 				lgr->peer_shutdown = 1;
 			list_move(&lgr->list, &lgr_free_list);
 			lgr->freeing = 1;
@@ -1860,9 +1868,12 @@ static bool smcr_lgr_match(struct smc_link_group *lgr, u8 smcr_version,
 }
 
 static bool smcd_lgr_match(struct smc_link_group *lgr,
-			   struct smcd_dev *smcismdev, u64 peer_gid)
+			   struct smcd_dev *smcismdev,
+			   struct smcd_gid *peer_gid)
 {
-	return lgr->peer_gid == peer_gid && lgr->smcd == smcismdev;
+	return lgr->peer_gid.gid == peer_gid->gid && lgr->smcd == smcismdev &&
+		smc_ism_is_virtual(smcismdev) ?
+		(lgr->peer_gid.gid_ext == peer_gid->gid_ext) : 1;
 }
 
 /* create a new SMC connection (and a new link group if necessary) */
@@ -1892,7 +1903,7 @@ int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini)
 		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]) :
+				    &ini->ism_peer_gid[ini->ism_selected]) :
 		     smcr_lgr_match(lgr, ini->smcr_version,
 				    ini->peer_systemid,
 				    ini->peer_gid, ini->peer_mac, role,
diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index 9f65678..1f17537 100644
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -17,9 +17,11 @@
 #include <linux/pci.h>
 #include <rdma/ib_verbs.h>
 #include <net/genetlink.h>
+#include <net/smc.h>
 
 #include "smc.h"
 #include "smc_ib.h"
+#include "smc_clc.h"
 
 #define SMC_RMBS_PER_LGR_MAX	255	/* max. # of RMBs per link group */
 #define SMC_CONN_PER_LGR_MIN	16	/* min. # of connections per link group */
@@ -355,7 +357,7 @@ struct smc_link_group {
 						/* max links can be added in lgr */
 		};
 		struct { /* SMC-D */
-			u64			peer_gid;
+			struct smcd_gid		peer_gid;
 						/* Peer GID (remote) */
 			struct smcd_dev		*smcd;
 						/* ISM device for VLAN reg. */
@@ -392,6 +394,11 @@ struct smc_init_info_smcrv2 {
 	struct smc_gidlist	gidlist;
 };
 
+#define SMC_MAX_V2_ISM_DEVS	SMCD_CLC_MAX_V2_GID_ENTRIES
+				/* max # of proposed non-native ISM devices,
+				 * which can't exceed the max # of CHID-GID
+				 * entries in CLC proposal SMC-Dv2 extension.
+				 */
 struct smc_init_info {
 	u8			is_smcd;
 	u8			smc_type_v1;
@@ -417,9 +424,9 @@ struct smc_init_info {
 	u32			ib_clcqpn;
 	struct smc_init_info_smcrv2 smcrv2;
 	/* SMC-D */
-	u64			ism_peer_gid[SMC_MAX_ISM_DEVS + 1];
-	struct smcd_dev		*ism_dev[SMC_MAX_ISM_DEVS + 1];
-	u16			ism_chid[SMC_MAX_ISM_DEVS + 1];
+	struct smcd_gid		ism_peer_gid[SMC_MAX_V2_ISM_DEVS + 1];
+	struct smcd_dev		*ism_dev[SMC_MAX_V2_ISM_DEVS + 1];
+	u16			ism_chid[SMC_MAX_V2_ISM_DEVS + 1];
 	u8			ism_offered_cnt; /* # of ISM devices offered */
 	u8			ism_selected;    /* index of selected ISM dev*/
 	u8			smcd_version;
@@ -545,7 +552,7 @@ static inline void smc_set_pci_values(struct pci_dev *pci_dev,
 void smc_lgr_put(struct smc_link_group *lgr);
 void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport);
 void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport);
-void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid,
+void smc_smcd_terminate(struct smcd_dev *dev, struct smcd_gid *peer_gid,
 			unsigned short vlan);
 void smc_smcd_terminate_all(struct smcd_dev *dev);
 void smc_smcr_terminate_all(struct smc_ib_device *smcibdev);
diff --git a/net/smc/smc_diag.c b/net/smc/smc_diag.c
index a584613..c180c18 100644
--- a/net/smc/smc_diag.c
+++ b/net/smc/smc_diag.c
@@ -21,6 +21,7 @@
 
 #include "smc.h"
 #include "smc_core.h"
+#include "smc_ism.h"
 
 struct smc_diag_dump_ctx {
 	int pos[2];
@@ -168,12 +169,14 @@ static int __smc_diag_dump(struct sock *sk, struct sk_buff *skb,
 		struct smc_connection *conn = &smc->conn;
 		struct smcd_diag_dmbinfo dinfo;
 		struct smcd_dev *smcd = conn->lgr->smcd;
+		struct smcd_gid smcd_gid;
 
 		memset(&dinfo, 0, sizeof(dinfo));
 
 		dinfo.linkid = *((u32 *)conn->lgr->id);
-		dinfo.peer_gid = conn->lgr->peer_gid;
-		dinfo.my_gid = smcd->ops->get_local_gid(smcd);
+		dinfo.peer_gid = conn->lgr->peer_gid.gid;
+		smcd->ops->get_local_gid(smcd, &smcd_gid);
+		dinfo.my_gid = smcd_gid.gid;
 		dinfo.token = conn->rmb_desc->token;
 		dinfo.peer_token = conn->peer_token;
 
diff --git a/net/smc/smc_ism.c b/net/smc/smc_ism.c
index fbee249..a33f861 100644
--- a/net/smc/smc_ism.c
+++ b/net/smc/smc_ism.c
@@ -44,7 +44,8 @@ static void smcd_handle_irq(struct ism_dev *ism, unsigned int dmbno,
 #endif
 
 /* Test if an ISM communication is possible - same CPC */
-int smc_ism_cantalk(u64 peer_gid, unsigned short vlan_id, struct smcd_dev *smcd)
+int smc_ism_cantalk(struct smcd_gid *peer_gid, unsigned short vlan_id,
+		    struct smcd_dev *smcd)
 {
 	return smcd->ops->query_remote_gid(smcd, peer_gid, vlan_id ? 1 : 0,
 					   vlan_id);
@@ -208,7 +209,7 @@ int smc_ism_register_dmb(struct smc_link_group *lgr, int dmb_len,
 	dmb.dmb_len = dmb_len;
 	dmb.sba_idx = dmb_desc->sba_idx;
 	dmb.vlan_id = lgr->vlan_id;
-	dmb.rgid = lgr->peer_gid;
+	dmb.rgid = lgr->peer_gid.gid;
 	rc = lgr->smcd->ops->register_dmb(lgr->smcd, &dmb, &smc_ism_client);
 	if (!rc) {
 		dmb_desc->sba_idx = dmb.sba_idx;
@@ -340,18 +341,20 @@ struct smc_ism_event_work {
 
 static void smcd_handle_sw_event(struct smc_ism_event_work *wrk)
 {
+	struct smcd_gid peer_gid = { .gid = wrk->event.tok,
+				     .gid_ext = 0 };
 	union smcd_sw_event_info ev_info;
 
 	ev_info.info = wrk->event.info;
 	switch (wrk->event.code) {
 	case ISM_EVENT_CODE_SHUTDOWN:	/* Peer shut down DMBs */
-		smc_smcd_terminate(wrk->smcd, wrk->event.tok, ev_info.vlan_id);
+		smc_smcd_terminate(wrk->smcd, &peer_gid, ev_info.vlan_id);
 		break;
 	case ISM_EVENT_CODE_TESTLINK:	/* Activity timer */
 		if (ev_info.code == ISM_EVENT_REQUEST) {
 			ev_info.code = ISM_EVENT_RESPONSE;
 			wrk->smcd->ops->signal_event(wrk->smcd,
-						     wrk->event.tok,
+						     &peer_gid,
 						     ISM_EVENT_REQUEST_IR,
 						     ISM_EVENT_CODE_TESTLINK,
 						     ev_info.info);
@@ -365,10 +368,12 @@ static void smc_ism_event_work(struct work_struct *work)
 {
 	struct smc_ism_event_work *wrk =
 		container_of(work, struct smc_ism_event_work, work);
+	struct smcd_gid smcd_gid = { .gid = wrk->event.tok,
+				     .gid_ext = 0 };
 
 	switch (wrk->event.type) {
 	case ISM_EVENT_GID:	/* GID event, token is peer GID */
-		smc_smcd_terminate(wrk->smcd, wrk->event.tok, VLAN_VID_MASK);
+		smc_smcd_terminate(wrk->smcd, &smcd_gid, VLAN_VID_MASK);
 		break;
 	case ISM_EVENT_DMB:
 		break;
@@ -525,7 +530,7 @@ int smc_ism_signal_shutdown(struct smc_link_group *lgr)
 	memcpy(ev_info.uid, lgr->id, SMC_LGR_ID_SIZE);
 	ev_info.vlan_id = lgr->vlan_id;
 	ev_info.code = ISM_EVENT_REQUEST;
-	rc = lgr->smcd->ops->signal_event(lgr->smcd, lgr->peer_gid,
+	rc = lgr->smcd->ops->signal_event(lgr->smcd, &lgr->peer_gid,
 					  ISM_EVENT_REQUEST_IR,
 					  ISM_EVENT_CODE_SHUTDOWN,
 					  ev_info.info);
diff --git a/net/smc/smc_ism.h b/net/smc/smc_ism.h
index d1228a6..0e5e563 100644
--- a/net/smc/smc_ism.h
+++ b/net/smc/smc_ism.h
@@ -32,7 +32,8 @@ struct smc_ism_vlanid {			/* VLAN id set on ISM device */
 
 struct smcd_dev;
 
-int smc_ism_cantalk(u64 peer_gid, unsigned short vlan_id, struct smcd_dev *dev);
+int smc_ism_cantalk(struct smcd_gid *peer_gid, unsigned short vlan_id,
+		    struct smcd_dev *dev);
 void smc_ism_set_conn(struct smc_connection *conn);
 void smc_ism_unset_conn(struct smc_connection *conn);
 int smc_ism_get_vlan(struct smcd_dev *dev, unsigned short vlan_id);
diff --git a/net/smc/smc_pnet.c b/net/smc/smc_pnet.c
index 1177540..9f2c58c 100644
--- a/net/smc/smc_pnet.c
+++ b/net/smc/smc_pnet.c
@@ -1103,8 +1103,8 @@ static void smc_pnet_find_ism_by_pnetid(struct net_device *ndev,
 	list_for_each_entry(ismdev, &smcd_dev_list.list, list) {
 		if (smc_pnet_match(ismdev->pnetid, ndev_pnetid) &&
 		    !ismdev->going_away &&
-		    (!ini->ism_peer_gid[0] ||
-		     !smc_ism_cantalk(ini->ism_peer_gid[0], ini->vlan_id,
+		    (!ini->ism_peer_gid[0].gid ||
+		     !smc_ism_cantalk(&ini->ism_peer_gid[0], ini->vlan_id,
 				      ismdev))) {
 			ini->ism_dev[0] = ismdev;
 			break;
-- 
1.8.3.1

Re: [PATCH net-next v5 6/9] net/smc: compatible with 128-bits extended GID of virtual ISM device

[Alexandra Winter]

On 08.12.23 08:40, Wen Gu wrote:
> According to virtual ISM support feature defined by SMCv2.1, GIDs of
> virtual ISM device are UUIDs defined by RFC4122, which are 128-bits
> long. So some adaptation work is required. And note that the GIDs of
> existing platform firmware ISM devices still remain 64-bits long.
> 
> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
> ---

Thank you Wen Gu.
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>

[PATCH net-next v5 7/9] net/smc: support extended GID in SMC-D lgr netlink attribute

[Wen Gu]

Virtual ISM devices introduced in SMCv2.1 requires a 128 bit extended
GID vs. the existing ISM 64bit GID. So the 2nd 64 bit of extended GID
should be included in SMC-D linkgroup netlink attribute as well.

Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
---
 include/uapi/linux/smc.h      | 2 ++
 include/uapi/linux/smc_diag.h | 2 ++
 net/smc/smc_core.c            | 6 ++++++
 net/smc/smc_diag.c            | 2 ++
 4 files changed, 12 insertions(+)

diff --git a/include/uapi/linux/smc.h b/include/uapi/linux/smc.h
index 837fcd4..b531e3e 100644
--- a/include/uapi/linux/smc.h
+++ b/include/uapi/linux/smc.h
@@ -160,6 +160,8 @@ enum {
 	SMC_NLA_LGR_D_CHID,		/* u16 */
 	SMC_NLA_LGR_D_PAD,		/* flag */
 	SMC_NLA_LGR_D_V2_COMMON,	/* nest */
+	SMC_NLA_LGR_D_EXT_GID,		/* u64 */
+	SMC_NLA_LGR_D_PEER_EXT_GID,	/* u64 */
 	__SMC_NLA_LGR_D_MAX,
 	SMC_NLA_LGR_D_MAX = __SMC_NLA_LGR_D_MAX - 1
 };
diff --git a/include/uapi/linux/smc_diag.h b/include/uapi/linux/smc_diag.h
index 8cb3a6f..58eceb7 100644
--- a/include/uapi/linux/smc_diag.h
+++ b/include/uapi/linux/smc_diag.h
@@ -107,6 +107,8 @@ struct smcd_diag_dmbinfo {		/* SMC-D Socket internals */
 	__aligned_u64	my_gid;		/* My GID */
 	__aligned_u64	token;		/* Token of DMB */
 	__aligned_u64	peer_token;	/* Token of remote DMBE */
+	__aligned_u64	peer_gid_ext;	/* Peer GID (extended part) */
+	__aligned_u64	my_gid_ext;	/* My GID (extended part) */
 };
 
 #endif /* _UAPI_SMC_DIAG_H_ */
diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index 672eff0..95cc954 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -526,9 +526,15 @@ static int smc_nl_fill_smcd_lgr(struct smc_link_group *lgr,
 	if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_GID,
 			      smcd_gid.gid, SMC_NLA_LGR_D_PAD))
 		goto errattr;
+	if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_EXT_GID,
+			      smcd_gid.gid_ext, SMC_NLA_LGR_D_PAD))
+		goto errattr;
 	if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_GID, lgr->peer_gid.gid,
 			      SMC_NLA_LGR_D_PAD))
 		goto errattr;
+	if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_EXT_GID,
+			      lgr->peer_gid.gid_ext, 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))
diff --git a/net/smc/smc_diag.c b/net/smc/smc_diag.c
index c180c18..3fbe14e 100644
--- a/net/smc/smc_diag.c
+++ b/net/smc/smc_diag.c
@@ -175,8 +175,10 @@ static int __smc_diag_dump(struct sock *sk, struct sk_buff *skb,
 
 		dinfo.linkid = *((u32 *)conn->lgr->id);
 		dinfo.peer_gid = conn->lgr->peer_gid.gid;
+		dinfo.peer_gid_ext = conn->lgr->peer_gid.gid_ext;
 		smcd->ops->get_local_gid(smcd, &smcd_gid);
 		dinfo.my_gid = smcd_gid.gid;
+		dinfo.my_gid_ext = smcd_gid.gid_ext;
 		dinfo.token = conn->rmb_desc->token;
 		dinfo.peer_token = conn->peer_token;
 
-- 
1.8.3.1

Re: [PATCH net-next v5 7/9] net/smc: support extended GID in SMC-D lgr netlink attribute

[Alexandra Winter]

On 08.12.23 08:40, Wen Gu wrote:
> Virtual ISM devices introduced in SMCv2.1 requires a 128 bit extended
> GID vs. the existing ISM 64bit GID. So the 2nd 64 bit of extended GID
> should be included in SMC-D linkgroup netlink attribute as well.
> 
> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
> ---

This patch did not apply cleanly.
Please always base patches on the current net-next

Re: [PATCH net-next v5 7/9] net/smc: support extended GID in SMC-D lgr netlink attribute

[Wen Gu]

On 2023/12/11 17:39, Alexandra Winter wrote:
> 
> 
> On 08.12.23 08:40, Wen Gu wrote:
>> Virtual ISM devices introduced in SMCv2.1 requires a 128 bit extended
>> GID vs. the existing ISM 64bit GID. So the 2nd 64 bit of extended GID
>> should be included in SMC-D linkgroup netlink attribute as well.
>>
>> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
>> ---
> 
> This patch did not apply cleanly.
> Please always base patches on the current net-next

Strange.. I can apply them cleanly with the latest net-next
(6e944cc68633 ("Merge branch 'rswitch-jumbo-frames'")).

Could you please try again? Thanks.

Re: [PATCH net-next v5 7/9] net/smc: support extended GID in SMC-D lgr netlink attribute

[Alexandra Winter]

On 11.12.23 11:09, Wen Gu wrote:
> 
> 
> On 2023/12/11 17:39, Alexandra Winter wrote:
>>
>>
>> On 08.12.23 08:40, Wen Gu wrote:
>>> Virtual ISM devices introduced in SMCv2.1 requires a 128 bit extended
>>> GID vs. the existing ISM 64bit GID. So the 2nd 64 bit of extended GID
>>> should be included in SMC-D linkgroup netlink attribute as well.
>>>
>>> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
>>> ---
>>
>> This patch did not apply cleanly.
>> Please always base patches on the current net-next
> 
> Strange.. I can apply them cleanly with the latest net-next
> (6e944cc68633 ("Merge branch 'rswitch-jumbo-frames'")).
> 
> Could you please try again? Thanks.
> 

Sorry, the patches were somehow re-ordered when I downloaded them from
https://lore.kernel.org/netdev/4ad3a168-f506-fc21-582d-fe8764f404c0@linux.alibaba.com/t.mbox.gz

Everything is ok with this patch.

[PATCH net-next v5 8/9] net/smc: disable SEID on non-s390 archs where virtual ISM may be used

[Wen Gu]

The system EID (SEID) is an internal EID used by SMC-D to represent the
s390 physical machine that OS is executing on. On s390 architecture, it
predefined by fixed string and part of cpuid and is enabled regardless
of whether underlay device is virtual ISM or platform firmware ISM.

However on non-s390 architectures where SMC-D can be used with virtual
ISM devices, there is no similar information to identify physical
machines, especially in virtualization scenarios. So in such cases, SEID
is forcibly disabled and the user-defined UEID will be used to represent
the communicable space.

Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
---
 net/smc/smc_clc.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
index 3604150..6d6cfa5 100644
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -155,10 +155,12 @@ static int smc_clc_ueid_remove(char *ueid)
 			rc = 0;
 		}
 	}
+#if IS_ENABLED(CONFIG_S390)
 	if (!rc && !smc_clc_eid_table.ueid_cnt) {
 		smc_clc_eid_table.seid_enabled = 1;
 		rc = -EAGAIN;	/* indicate success and enabling of seid */
 	}
+#endif
 	write_unlock(&smc_clc_eid_table.lock);
 	return rc;
 }
@@ -273,22 +275,30 @@ int smc_nl_dump_seid(struct sk_buff *skb, struct netlink_callback *cb)
 
 int smc_nl_enable_seid(struct sk_buff *skb, struct genl_info *info)
 {
+#if IS_ENABLED(CONFIG_S390)
 	write_lock(&smc_clc_eid_table.lock);
 	smc_clc_eid_table.seid_enabled = 1;
 	write_unlock(&smc_clc_eid_table.lock);
 	return 0;
+#else
+	return -EOPNOTSUPP;
+#endif
 }
 
 int smc_nl_disable_seid(struct sk_buff *skb, struct genl_info *info)
 {
 	int rc = 0;
 
+#if IS_ENABLED(CONFIG_S390)
 	write_lock(&smc_clc_eid_table.lock);
 	if (!smc_clc_eid_table.ueid_cnt)
 		rc = -ENOENT;
 	else
 		smc_clc_eid_table.seid_enabled = 0;
 	write_unlock(&smc_clc_eid_table.lock);
+#else
+	rc = -EOPNOTSUPP;
+#endif
 	return rc;
 }
 
@@ -1336,7 +1346,11 @@ void __init smc_clc_init(void)
 	INIT_LIST_HEAD(&smc_clc_eid_table.list);
 	rwlock_init(&smc_clc_eid_table.lock);
 	smc_clc_eid_table.ueid_cnt = 0;
+#if IS_ENABLED(CONFIG_S390)
 	smc_clc_eid_table.seid_enabled = 1;
+#else
+	smc_clc_eid_table.seid_enabled = 0;
+#endif
 }
 
 void smc_clc_exit(void)
-- 
1.8.3.1

[PATCH net-next v5 9/9] net/smc: manage system EID in SMC stack instead of ISM driver

[Wen Gu]

The System EID (SEID) is an internal EID that is used by the SMCv2
software stack that has a predefined and constant value representing
the s390 physical machine that the OS is executing on. So it should
be managed by SMC stack instead of ISM driver and be consistent for
all ISMv2 device (including virtual ISM devices) on s390 architecture.

Suggested-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
---
 drivers/s390/net/ism.h     |  7 -------
 drivers/s390/net/ism_drv.c | 38 ++++++--------------------------------
 include/linux/ism.h        |  1 -
 include/net/smc.h          |  1 -
 net/smc/smc_ism.c          | 33 ++++++++++++++++++++++++---------
 net/smc/smc_ism.h          |  7 +++++++
 6 files changed, 37 insertions(+), 50 deletions(-)

diff --git a/drivers/s390/net/ism.h b/drivers/s390/net/ism.h
index 70c5bbd..047fa610 100644
--- a/drivers/s390/net/ism.h
+++ b/drivers/s390/net/ism.h
@@ -16,7 +16,6 @@
  */
 #define ISM_DMB_WORD_OFFSET	1
 #define ISM_DMB_BIT_OFFSET	(ISM_DMB_WORD_OFFSET * 32)
-#define ISM_IDENT_MASK		0x00FFFF
 
 #define ISM_REG_SBA	0x1
 #define ISM_REG_IEQ	0x2
@@ -192,12 +191,6 @@ struct ism_sba {
 #define ISM_CREATE_REQ(dmb, idx, sf, offset)		\
 	((dmb) | (idx) << 24 | (sf) << 23 | (offset))
 
-struct ism_systemeid {
-	u8	seid_string[24];
-	u8	serial_number[4];
-	u8	type[4];
-};
-
 static inline void __ism_read_cmd(struct ism_dev *ism, void *data,
 				  unsigned long offset, unsigned long len)
 {
diff --git a/drivers/s390/net/ism_drv.c b/drivers/s390/net/ism_drv.c
index 34dd063..2c8e964 100644
--- a/drivers/s390/net/ism_drv.c
+++ b/drivers/s390/net/ism_drv.c
@@ -36,6 +36,7 @@
 						/* a list for fast mapping  */
 static u8 max_client;
 static DEFINE_MUTEX(clients_lock);
+static bool ism_v2_capable;
 struct ism_dev_list {
 	struct list_head list;
 	struct mutex mutex; /* protects ism device list */
@@ -443,32 +444,6 @@ int ism_move(struct ism_dev *ism, u64 dmb_tok, unsigned int idx, bool sf,
 }
 EXPORT_SYMBOL_GPL(ism_move);
 
-static struct ism_systemeid SYSTEM_EID = {
-	.seid_string = "IBM-SYSZ-ISMSEID00000000",
-	.serial_number = "0000",
-	.type = "0000",
-};
-
-static void ism_create_system_eid(void)
-{
-	struct cpuid id;
-	u16 ident_tail;
-	char tmp[5];
-
-	get_cpu_id(&id);
-	ident_tail = (u16)(id.ident & ISM_IDENT_MASK);
-	snprintf(tmp, 5, "%04X", ident_tail);
-	memcpy(&SYSTEM_EID.serial_number, tmp, 4);
-	snprintf(tmp, 5, "%04X", id.machine);
-	memcpy(&SYSTEM_EID.type, tmp, 4);
-}
-
-u8 *ism_get_seid(void)
-{
-	return SYSTEM_EID.seid_string;
-}
-EXPORT_SYMBOL_GPL(ism_get_seid);
-
 static void ism_handle_event(struct ism_dev *ism)
 {
 	struct ism_event *entry;
@@ -560,7 +535,9 @@ static int ism_dev_init(struct ism_dev *ism)
 
 	if (!ism_add_vlan_id(ism, ISM_RESERVED_VLANID))
 		/* hardware is V2 capable */
-		ism_create_system_eid();
+		ism_v2_capable = true;
+	else
+		ism_v2_capable = false;
 
 	mutex_lock(&ism_dev_list.mutex);
 	mutex_lock(&clients_lock);
@@ -665,8 +642,7 @@ static void ism_dev_exit(struct ism_dev *ism)
 	}
 	mutex_unlock(&clients_lock);
 
-	if (SYSTEM_EID.serial_number[0] != '0' ||
-	    SYSTEM_EID.type[0] != '0')
+	if (ism_v2_capable)
 		ism_del_vlan_id(ism, ISM_RESERVED_VLANID);
 	unregister_ieq(ism);
 	unregister_sba(ism);
@@ -813,8 +789,7 @@ static int smcd_move(struct smcd_dev *smcd, u64 dmb_tok, unsigned int idx,
 
 static int smcd_supports_v2(void)
 {
-	return SYSTEM_EID.serial_number[0] != '0' ||
-		SYSTEM_EID.type[0] != '0';
+	return ism_v2_capable;
 }
 
 static u64 ism_get_local_gid(struct ism_dev *ism)
@@ -860,7 +835,6 @@ static inline struct device *smcd_get_dev(struct smcd_dev *dev)
 	.signal_event = smcd_signal_ieq,
 	.move_data = smcd_move,
 	.supports_v2 = smcd_supports_v2,
-	.get_system_eid = ism_get_seid,
 	.get_local_gid = smcd_get_local_gid,
 	.get_chid = smcd_get_chid,
 	.get_dev = smcd_get_dev,
diff --git a/include/linux/ism.h b/include/linux/ism.h
index 9a4c204..5428edd 100644
--- a/include/linux/ism.h
+++ b/include/linux/ism.h
@@ -86,7 +86,6 @@ int  ism_register_dmb(struct ism_dev *dev, struct ism_dmb *dmb,
 int  ism_unregister_dmb(struct ism_dev *dev, struct ism_dmb *dmb);
 int  ism_move(struct ism_dev *dev, u64 dmb_tok, unsigned int idx, bool sf,
 	      unsigned int offset, void *data, unsigned int size);
-u8  *ism_get_seid(void);
 
 const struct smcd_ops *ism_get_smcd_ops(void);
 
diff --git a/include/net/smc.h b/include/net/smc.h
index a0dc1187e..c9dcb30 100644
--- a/include/net/smc.h
+++ b/include/net/smc.h
@@ -73,7 +73,6 @@ struct smcd_ops {
 			 bool sf, unsigned int offset, void *data,
 			 unsigned int size);
 	int (*supports_v2)(void);
-	u8* (*get_system_eid)(void);
 	void (*get_local_gid)(struct smcd_dev *dev, struct smcd_gid *gid);
 	u16 (*get_chid)(struct smcd_dev *dev);
 	struct device* (*get_dev)(struct smcd_dev *dev);
diff --git a/net/smc/smc_ism.c b/net/smc/smc_ism.c
index a33f861..ac88de2 100644
--- a/net/smc/smc_ism.c
+++ b/net/smc/smc_ism.c
@@ -43,6 +43,27 @@ static void smcd_handle_irq(struct ism_dev *ism, unsigned int dmbno,
 };
 #endif
 
+static void smc_ism_create_system_eid(void)
+{
+	struct smc_ism_seid *seid =
+		(struct smc_ism_seid *)smc_ism_v2_system_eid;
+#if IS_ENABLED(CONFIG_S390)
+	struct cpuid id;
+	u16 ident_tail;
+	char tmp[5];
+
+	memcpy(seid->seid_string, "IBM-SYSZ-ISMSEID00000000", 24);
+	get_cpu_id(&id);
+	ident_tail = (u16)(id.ident & SMC_ISM_IDENT_MASK);
+	snprintf(tmp, 5, "%04X", ident_tail);
+	memcpy(seid->serial_number, tmp, 4);
+	snprintf(tmp, 5, "%04X", id.machine);
+	memcpy(seid->type, tmp, 4);
+#else
+	memset(seid, 0, SMC_MAX_EID_LEN);
+#endif
+}
+
 /* Test if an ISM communication is possible - same CPC */
 int smc_ism_cantalk(struct smcd_gid *peer_gid, unsigned short vlan_id,
 		    struct smcd_dev *smcd)
@@ -431,14 +452,8 @@ static void smcd_register_dev(struct ism_dev *ism)
 
 	mutex_lock(&smcd_dev_list.mutex);
 	if (list_empty(&smcd_dev_list.list)) {
-		u8 *system_eid = NULL;
-
-		system_eid = smcd->ops->get_system_eid();
-		if (smcd->ops->supports_v2()) {
+		if (smcd->ops->supports_v2())
 			smc_ism_v2_capable = true;
-			memcpy(smc_ism_v2_system_eid, system_eid,
-			       SMC_MAX_EID_LEN);
-		}
 	}
 	/* sort list: devices without pnetid before devices with pnetid */
 	if (smcd->pnetid[0])
@@ -542,10 +557,10 @@ int smc_ism_init(void)
 {
 	int rc = 0;
 
-#if IS_ENABLED(CONFIG_ISM)
 	smc_ism_v2_capable = false;
-	memset(smc_ism_v2_system_eid, 0, SMC_MAX_EID_LEN);
+	smc_ism_create_system_eid();
 
+#if IS_ENABLED(CONFIG_ISM)
 	rc = ism_register_client(&smc_ism_client);
 #endif
 	return rc;
diff --git a/net/smc/smc_ism.h b/net/smc/smc_ism.h
index 0e5e563..ffff40c 100644
--- a/net/smc/smc_ism.h
+++ b/net/smc/smc_ism.h
@@ -16,6 +16,7 @@
 #include "smc.h"
 
 #define SMC_VIRTUAL_ISM_CHID_MASK	0xFF00
+#define SMC_ISM_IDENT_MASK		0x00FFFF
 
 struct smcd_dev_list {	/* List of SMCD devices */
 	struct list_head list;
@@ -30,6 +31,12 @@ struct smc_ism_vlanid {			/* VLAN id set on ISM device */
 	refcount_t refcnt;		/* Reference count */
 };
 
+struct smc_ism_seid {
+	u8 seid_string[24];
+	u8 serial_number[4];
+	u8 type[4];
+};
+
 struct smcd_dev;
 
 int smc_ism_cantalk(struct smcd_gid *peer_gid, unsigned short vlan_id,
-- 
1.8.3.1

Re: [PATCH net-next v5 9/9] net/smc: manage system EID in SMC stack instead of ISM driver

[Alexandra Winter]

On 08.12.23 08:40, Wen Gu wrote:
> The System EID (SEID) is an internal EID that is used by the SMCv2
> software stack that has a predefined and constant value representing
> the s390 physical machine that the OS is executing on. So it should
> be managed by SMC stack instead of ISM driver and be consistent for
> all ISMv2 device (including virtual ISM devices) on s390 architecture.
> 
> Suggested-by: Alexandra Winter <wintera@linux.ibm.com>
> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
> ---

I've sent you a Reviewed-by for v3 of this patch. Did you lose it?