[PATCH net-next v2 10/15] net/smc: Introduce SMCR get link command

Karsten Graul
2020-11-03T10:25:26Z

Introduce get link command which loops through
all available links of all available link groups. It
uses the SMC-R linkgroup list as entry point, not
the socket list, which makes linkgroup diagnosis
possible, in case linkgroup does not contain active
connections anymore.

Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
---
include/uapi/linux/smc_diag.h | 8 +++++
net/smc/smc_diag.c | 62 ++++++++++++++++++++++++++++++++++-
2 files changed, 69 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/smc_diag.h b/include/uapi/linux/smc_diag.h
index 6ae028344b6d..a57df0296aa4 100644
--- a/include/uapi/linux/smc_diag.h
+++ b/include/uapi/linux/smc_diag.h
@@ -4,6 +4,7 @@

#include <linux/types.h>
#include <linux/inet_diag.h>
+#include <linux/if.h>
#include <linux/smc.h>
#include <rdma/ib_user_verbs.h>

@@ -79,6 +80,7 @@ enum {
/* SMC_DIAG_GET_LGR_INFO command extensions */
enum {
SMC_DIAG_LGR_INFO_SMCR = 1,
+ SMC_DIAG_LGR_INFO_SMCR_LINK,
};

#define SMC_DIAG_MAX (__SMC_DIAG_MAX - 1)
@@ -129,6 +131,12 @@ struct smc_diag_linkinfo {
__u8 ibport; /* RDMA device port number */
__u8 gid[40]; /* local GID */
__u8 peer_gid[40]; /* peer GID */
+ /* Fields above used by legacy v1 code */
+ __u32 conn_cnt;
+ __u8 netdev[IFNAMSIZ]; /* ethernet device name */
+ __u8 link_uid[4]; /* unique link id */
+ __u8 peer_link_uid[4]; /* unique peer link id */
+ __u32 link_state; /* link state */
};

struct smc_diag_lgrinfo {
diff --git a/net/smc/smc_diag.c b/net/smc/smc_diag.c
index c53904b3f350..6885814b6e4f 100644
--- a/net/smc/smc_diag.c
+++ b/net/smc/smc_diag.c
@@ -20,6 +20,7 @@
#include <net/smc.h>

#include "smc.h"
+#include "smc_ib.h"
#include "smc_core.h"

struct smc_diag_dump_ctx {
@@ -203,6 +204,54 @@ static bool smc_diag_fill_dmbinfo(struct sock *sk, struct sk_buff *skb)
return true;
}

+static int smc_diag_fill_lgr_link(struct smc_link_group *lgr,
+ struct smc_link *link,
+ struct sk_buff *skb,
+ struct netlink_callback *cb,
+ struct smc_diag_req_v2 *req)
+{
+ struct smc_diag_linkinfo link_info;
+ int dummy = 0, rc = 0;
+ struct nlmsghdr *nlh;
+
+ nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, MAGIC_SEQ_V2_ACK,
+ cb->nlh->nlmsg_type, 0, NLM_F_MULTI);
+
+ memset(&link_info, 0, sizeof(link_info));
+ link_info.link_state = link->state;
+ link_info.link_id = link->link_id;
+ link_info.conn_cnt = atomic_read(&link->conn_cnt);
+ link_info.ibport = link->ibport;
+
+ memcpy(link_info.link_uid, link->link_uid,
+ sizeof(link_info.link_uid));
+ snprintf(link_info.ibname, sizeof(link_info.ibname), "%s",
+ link->ibname);
+ snprintf(link_info.netdev, sizeof(link_info.netdev), "%s",
+ link->ndevname);
+ memcpy(link_info.peer_link_uid, link->peer_link_uid,
+ sizeof(link_info.peer_link_uid));
+
+ smc_gid_be16_convert(link_info.gid,
+ link->gid);
+ smc_gid_be16_convert(link_info.peer_gid,
+ link->peer_gid);
+
+ /* Just a command place holder to signal back the command reply type */
+ if (nla_put(skb, SMC_DIAG_GET_LGR_INFO, sizeof(dummy), &dummy) < 0)
+ goto errout;
+ if (nla_put(skb, SMC_DIAG_LGR_INFO_SMCR_LINK,
+ sizeof(link_info), &link_info) < 0)
+ goto errout;
+
+ nlmsg_end(skb, nlh);
+ return rc;
+
+errout:
+ nlmsg_cancel(skb, nlh);
+ return -EMSGSIZE;
+}
+
static int smc_diag_fill_lgr(struct smc_link_group *lgr,
struct sk_buff *skb,
struct netlink_callback *cb,
@@ -238,7 +287,7 @@ static int smc_diag_handle_lgr(struct smc_link_group *lgr,
struct smc_diag_req_v2 *req)
{
struct nlmsghdr *nlh;
- int rc = 0;
+ int i, rc = 0;

nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, MAGIC_SEQ_V2_ACK,
cb->nlh->nlmsg_type, 0, NLM_F_MULTI);
@@ -250,6 +299,17 @@ static int smc_diag_handle_lgr(struct smc_link_group *lgr,
goto errout;

nlmsg_end(skb, nlh);
+
+ if ((req->cmd_ext & (1 << (SMC_DIAG_LGR_INFO_SMCR_LINK - 1)))) {
+ for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
+ if (!smc_link_usable(&lgr->lnk[i]))
+ continue;
+ rc = smc_diag_fill_lgr_link(lgr, &lgr->lnk[i], skb,
+ cb, req);
+ if (rc < 0)
+ goto errout;
+ }
+ }
return rc;

errout:
--
2.17.1