diff mbox series

[RFC,net-next,4/6] net/smc: support max connections per lgr negotiation

Message ID 20230803132422.6280-5-guangguan.wang@linux.alibaba.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series net/smc: serveral features's implementation for smc v2.1 | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1328 this patch: 1328
netdev/cc_maintainers success CCed 12 of 12 maintainers
netdev/build_clang success Errors and warnings before: 1351 this patch: 1351
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1351 this patch: 1351
netdev/checkpatch warning WARNING: line length of 82 exceeds 80 columns WARNING: line length of 85 exceeds 80 columns WARNING: line length of 89 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Guangguan Wang Aug. 3, 2023, 1:24 p.m. UTC 
Support max connections per lgr negotiation for SMCR v2.1,
which is one of smc v2.1 features.

Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
---
 net/smc/af_smc.c   |  1 +
 net/smc/smc_clc.c  | 41 +++++++++++++++++++++++++++++++++++++++--
 net/smc/smc_clc.h  |  7 +++++--
 net/smc/smc_core.c |  4 +++-
 net/smc/smc_core.h |  4 ++++
 net/smc/smc_llc.c  |  6 +++++-
 6 files changed, 57 insertions(+), 6 deletions(-)

Comments

Simon Horman Aug. 3, 2023, 5:55 p.m. UTC | #1 
On Thu, Aug 03, 2023 at 09:24:20PM +0800, Guangguan Wang wrote:
> Support max connections per lgr negotiation for SMCR v2.1,
> which is one of smc v2.1 features.
> 
> Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com>
> Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>

...

Hi Guangguan Wang,

>  int smc_clc_cli_v2x_features_validate(struct smc_clc_first_contact_ext *fce,
>  				      struct smc_init_info *ini)
>  {
> +	struct smc_clc_first_contact_ext_v2x *fce_v2x =
> +		(struct smc_clc_first_contact_ext_v2x *)fce;
> +
>  	if (ini->release_ver < SMC_RELEASE_1)
>  		return 0;
>  
> +	if (!ini->is_smcd) {
> +		if (fce_v2x->max_conns > SMC_CONN_PER_LGR_MAX)

The type of the max_cons field is u8.
The value of SMC_CONN_PER_LGR_MAX is 255 (in another patch of this series),
the maximum value that the max_cons field can be assigned.
So it seems that this condition cannot ever be true.

As flagged by Smatch.

> +			return SMC_CLC_DECL_MAXCONNERR;
> +		ini->max_conns = fce_v2x->max_conns;
> +	}
> +
>  	return 0;
>  }

...

> diff --git a/net/smc/smc_clc.h b/net/smc/smc_clc.h

...

> @@ -236,7 +238,8 @@ struct smc_clc_first_contact_ext {
>  
>  struct smc_clc_first_contact_ext_v2x {
>  	struct smc_clc_first_contact_ext fce_v20;
> -	u8 reserved3[4];
> +	u8 max_conns; /* for SMC-R only */
> +	u8 reserved3[3];
>  	__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 1a97fef39127..065369dc6584 100644
> --- a/net/smc/smc_core.h
> +++ b/net/smc/smc_core.h
> @@ -22,6 +22,7 @@
>  #include "smc_ib.h"
>  
>  #define SMC_RMBS_PER_LGR_MAX	255	/* max. # of RMBs per link group */
> +#define SMC_CONN_PER_LGR_MAX	255	/* max. # of connections per link group */
>  
>  struct smc_lgr_list {			/* list of link group definition */
>  	struct list_head	list;
Guangguan Wang Aug. 4, 2023, 6:40 a.m. UTC | #2 
Got it.
I will remove the check in the next version.

Thanks,
Guangguan Wang

On 2023/8/4 01:55, Simon Horman wrote:
> On Thu, Aug 03, 2023 at 09:24:20PM +0800, Guangguan Wang wrote:
>> Support max connections per lgr negotiation for SMCR v2.1,
>> which is one of smc v2.1 features.
>>
>> Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com>
>> Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
> 
> ...
> 
> Hi Guangguan Wang,
> 
>>  int smc_clc_cli_v2x_features_validate(struct smc_clc_first_contact_ext *fce,
>>  				      struct smc_init_info *ini)
>>  {
>> +	struct smc_clc_first_contact_ext_v2x *fce_v2x =
>> +		(struct smc_clc_first_contact_ext_v2x *)fce;
>> +
>>  	if (ini->release_ver < SMC_RELEASE_1)
>>  		return 0;
>>  
>> +	if (!ini->is_smcd) {
>> +		if (fce_v2x->max_conns > SMC_CONN_PER_LGR_MAX)
> 
> The type of the max_cons field is u8.
> The value of SMC_CONN_PER_LGR_MAX is 255 (in another patch of this series),
> the maximum value that the max_cons field can be assigned.
> So it seems that this condition cannot ever be true.
> 
> As flagged by Smatch.
> 
>> +			return SMC_CLC_DECL_MAXCONNERR;
>> +		ini->max_conns = fce_v2x->max_conns;
>> +	}
>> +
>>  	return 0;
>>  }
> 
> ...
> 
>> diff --git a/net/smc/smc_clc.h b/net/smc/smc_clc.h
> 
> ...
> 
>> @@ -236,7 +238,8 @@ struct smc_clc_first_contact_ext {
>>  
>>  struct smc_clc_first_contact_ext_v2x {
>>  	struct smc_clc_first_contact_ext fce_v20;
>> -	u8 reserved3[4];
>> +	u8 max_conns; /* for SMC-R only */
>> +	u8 reserved3[3];
>>  	__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 1a97fef39127..065369dc6584 100644
>> --- a/net/smc/smc_core.h
>> +++ b/net/smc/smc_core.h
>> @@ -22,6 +22,7 @@
>>  #include "smc_ib.h"
>>  
>>  #define SMC_RMBS_PER_LGR_MAX	255	/* max. # of RMBs per link group */
>> +#define SMC_CONN_PER_LGR_MAX	255	/* max. # of connections per link group */
>>  
>>  struct smc_lgr_list {			/* list of link group definition */
>>  	struct list_head	list;
diff mbox series

Patch

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index fd58e25beddf..b95d3fd48c28 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -1214,6 +1214,7 @@  static int smc_connect_rdma(struct smc_sock *smc,
 	memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
 	memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
 	memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
+	ini->max_conns = SMC_RMBS_PER_LGR_MAX;
 
 	reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
 	if (reason_code)
diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
index b25a72f1c9ac..5e90234df189 100644
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -427,9 +427,17 @@  static int smc_clc_fill_fce(struct smc_clc_first_contact_ext_v2x *fce,
 	fce->fce_v20.os_type = SMC_CLC_OS_LINUX;
 	fce->fce_v20.release = ini->release_ver;
 	memcpy(fce->fce_v20.hostname, smc_hostname, sizeof(smc_hostname));
-	if (ini->is_smcd && ini->release_ver < SMC_RELEASE_1)
+	if (ini->is_smcd && ini->release_ver < SMC_RELEASE_1) {
 		ret = sizeof(struct smc_clc_first_contact_ext);
+		goto out;
+	}
+
+	if (ini->release_ver >= SMC_RELEASE_1) {
+		if (!ini->is_smcd)
+			fce->max_conns = ini->max_conns;
+	}
 
+out:
 	return ret;
 }
 
@@ -931,8 +939,10 @@  int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
 				sizeof(struct smc_clc_smcd_gid_chid);
 		}
 	}
-	if (smcr_indicated(ini->smc_type_v2))
+	if (smcr_indicated(ini->smc_type_v2)) {
 		memcpy(v2_ext->roce, ini->smcrv2.ib_gid_v2, SMC_GID_SIZE);
+		v2_ext->max_conns = SMC_CONN_PER_LGR_MAX;
+	}
 
 	pclc_base->hdr.length = htons(plen);
 	memcpy(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
@@ -1163,6 +1173,11 @@  int smc_clc_srv_v2x_features_validate(struct smc_clc_msg_proposal *pclc,
 {
 	struct smc_clc_v2_extension *pclc_v2_ext;
 
+	/* default max conn is SMC_RMBS_PER_LGR_MAX(255),
+	 * which is the default value in smc v1 and v2.0.
+	 */
+	ini->max_conns = SMC_RMBS_PER_LGR_MAX;
+
 	if ((!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) ||
 	    ini->release_ver < SMC_RELEASE_1)
 		return 0;
@@ -1171,15 +1186,30 @@  int smc_clc_srv_v2x_features_validate(struct smc_clc_msg_proposal *pclc,
 	if (!pclc_v2_ext)
 		return SMC_CLC_DECL_NOV2EXT;
 
+	if (ini->smcr_version & SMC_V2) {
+		ini->max_conns = min_t(u8, pclc_v2_ext->max_conns, SMC_CONN_PER_LGR_MAX);
+		if (!ini->max_conns)
+			return SMC_CLC_DECL_MAXCONNERR;
+	}
+
 	return 0;
 }
 
 int smc_clc_cli_v2x_features_validate(struct smc_clc_first_contact_ext *fce,
 				      struct smc_init_info *ini)
 {
+	struct smc_clc_first_contact_ext_v2x *fce_v2x =
+		(struct smc_clc_first_contact_ext_v2x *)fce;
+
 	if (ini->release_ver < SMC_RELEASE_1)
 		return 0;
 
+	if (!ini->is_smcd) {
+		if (fce_v2x->max_conns > SMC_CONN_PER_LGR_MAX)
+			return SMC_CLC_DECL_MAXCONNERR;
+		ini->max_conns = fce_v2x->max_conns;
+	}
+
 	return 0;
 }
 
@@ -1190,6 +1220,8 @@  int smc_clc_v2x_features_confirm_check(struct smc_clc_msg_accept_confirm *cclc,
 		(struct smc_clc_msg_accept_confirm_v2 *)cclc;
 	struct smc_clc_first_contact_ext *fce =
 		smc_get_clc_first_contact_ext(clc_v2, ini->is_smcd);
+	struct smc_clc_first_contact_ext_v2x *fce_v2x =
+		(struct smc_clc_first_contact_ext_v2x *)fce;
 
 	if (cclc->hdr.version == SMC_V1 ||
 	    !(cclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
@@ -1201,6 +1233,11 @@  int smc_clc_v2x_features_confirm_check(struct smc_clc_msg_accept_confirm *cclc,
 	if (fce->release < SMC_RELEASE_1)
 		return 0;
 
+	if (!ini->is_smcd) {
+		if (fce_v2x->max_conns != ini->max_conns)
+			return SMC_CLC_DECL_MAXCONNERR;
+	}
+
 	return 0;
 }
 
diff --git a/net/smc/smc_clc.h b/net/smc/smc_clc.h
index 66932bfdc6d0..54077e50c368 100644
--- a/net/smc/smc_clc.h
+++ b/net/smc/smc_clc.h
@@ -46,6 +46,7 @@ 
 #define SMC_CLC_DECL_NOSMCD2DEV	0x03030007  /* no SMC-Dv2 device found	      */
 #define SMC_CLC_DECL_NOUEID	0x03030008  /* peer sent no UEID	      */
 #define SMC_CLC_DECL_RELEASEERR	0x03030009  /* release version negotiate failed */
+#define SMC_CLC_DECL_MAXCONNERR	0x0303000a  /* max connections negotiate failed */
 #define SMC_CLC_DECL_MODEUNSUPP	0x03040000  /* smc modes do not match (R or D)*/
 #define SMC_CLC_DECL_RMBE_EC	0x03050000  /* peer has eyecatcher in RMBE    */
 #define SMC_CLC_DECL_OPTUNSUPP	0x03060000  /* fastopen sockopt not supported */
@@ -134,7 +135,8 @@  struct smc_clc_smcd_gid_chid {
 struct smc_clc_v2_extension {
 	struct smc_clnt_opts_area_hdr hdr;
 	u8 roce[16];		/* RoCEv2 GID */
-	u8 reserved[16];
+	u8 max_conns;
+	u8 reserved[15];
 	u8 user_eids[][SMC_MAX_EID_LEN];
 };
 
@@ -236,7 +238,8 @@  struct smc_clc_first_contact_ext {
 
 struct smc_clc_first_contact_ext_v2x {
 	struct smc_clc_first_contact_ext fce_v20;
-	u8 reserved3[4];
+	u8 max_conns; /* for SMC-R only */
+	u8 reserved3[3];
 	__be32 vendor_exp_options;
 	u8 reserved4[8];
 } __packed;		/* format defined in
diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index 6aa3db47a956..5de1fbaa6e28 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -895,9 +895,11 @@  static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
 			lgr->uses_gateway = ini->smcrv2.uses_gateway;
 			memcpy(lgr->nexthop_mac, ini->smcrv2.nexthop_mac,
 			       ETH_ALEN);
+			lgr->max_conns = ini->max_conns;
 		} else {
 			ibdev = ini->ib_dev;
 			ibport = ini->ib_port;
+			lgr->max_conns = SMC_RMBS_PER_LGR_MAX;
 		}
 		memcpy(lgr->pnet_id, ibdev->pnetid[ibport - 1],
 		       SMC_MAX_PNETID_LEN);
@@ -1890,7 +1892,7 @@  int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini)
 		    (ini->smcd_version == SMC_V2 ||
 		     lgr->vlan_id == ini->vlan_id) &&
 		    (role == SMC_CLNT || ini->is_smcd ||
-		    (lgr->conns_num < SMC_RMBS_PER_LGR_MAX &&
+		    (lgr->conns_num < lgr->max_conns &&
 		      !bitmap_full(lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX)))) {
 			/* link group found */
 			ini->first_contact_local = 0;
diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index 1a97fef39127..065369dc6584 100644
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -22,6 +22,7 @@ 
 #include "smc_ib.h"
 
 #define SMC_RMBS_PER_LGR_MAX	255	/* max. # of RMBs per link group */
+#define SMC_CONN_PER_LGR_MAX	255	/* max. # of connections per link group */
 
 struct smc_lgr_list {			/* list of link group definition */
 	struct list_head	list;
@@ -331,6 +332,8 @@  struct smc_link_group {
 			__be32			saddr;
 						/* net namespace */
 			struct net		*net;
+			u8			max_conns;
+						/* max conn can be assigned to lgr */
 		};
 		struct { /* SMC-D */
 			u64			peer_gid;
@@ -375,6 +378,7 @@  struct smc_init_info {
 	u8			smc_type_v1;
 	u8			smc_type_v2;
 	u8			release_ver;
+	u8			max_conns;
 	u8			first_contact_peer;
 	u8			first_contact_local;
 	unsigned short		vlan_id;
diff --git a/net/smc/smc_llc.c b/net/smc/smc_llc.c
index 90f0b60b196a..5347b62f1518 100644
--- a/net/smc/smc_llc.c
+++ b/net/smc/smc_llc.c
@@ -52,7 +52,8 @@  struct smc_llc_msg_confirm_link {	/* type 0x01 */
 	u8 link_num;
 	u8 link_uid[SMC_LGR_ID_SIZE];
 	u8 max_links;
-	u8 reserved[9];
+	u8 max_conns;
+	u8 reserved[8];
 };
 
 #define SMC_LLC_FLAG_ADD_LNK_REJ	0x40
@@ -472,6 +473,9 @@  int smc_llc_send_confirm_link(struct smc_link *link,
 	confllc->link_num = link->link_id;
 	memcpy(confllc->link_uid, link->link_uid, SMC_LGR_ID_SIZE);
 	confllc->max_links = SMC_LLC_ADD_LNK_MAX_LINKS;
+	if (link->lgr->smc_version == SMC_V2 &&
+	    link->lgr->peer_smc_release >= SMC_RELEASE_1)
+		confllc->max_conns = link->lgr->max_conns;
 	/* send llc message */
 	rc = smc_wr_tx_send(link, pend);
 put_out: