net/smc: Introduce SMCR get linkgroup command

Introduce get linkgroup command which loops through
all available SMCR linkgroups. 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>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/include/uapi/linux/smc.h b/include/uapi/linux/smc.h
index 1b8d4e7..3ae8ca4 100644 (file)
--- a/include/uapi/linux/smc.h
+++ b/include/uapi/linux/smc.h
@@ -40,12 +40,14 @@ enum {                              /* SMC PNET Table commands */
 /* SMC_GENL_FAMILY commands */
 enum {
        SMC_NETLINK_GET_SYS_INFO = 1,
+       SMC_NETLINK_GET_LGR_SMCR,
 };
 
 /* SMC_GENL_FAMILY top level attributes */
 enum {
        SMC_GEN_UNSPEC,
        SMC_GEN_SYS_INFO,               /* nest */
+       SMC_GEN_LGR_SMCR,               /* nest */
        __SMC_GEN_MAX,
        SMC_GEN_MAX = __SMC_GEN_MAX - 1
 };
@@ -62,4 +64,17 @@ enum {
        SMC_NLA_SYS_MAX = __SMC_NLA_SYS_MAX - 1
 };
 
+/* SMC_GEN_LGR_SMCR attributes */
+enum {
+       SMC_NLA_LGR_R_UNSPEC,
+       SMC_NLA_LGR_R_ID,               /* u32 */
+       SMC_NLA_LGR_R_ROLE,             /* u8 */
+       SMC_NLA_LGR_R_TYPE,             /* u8 */
+       SMC_NLA_LGR_R_PNETID,           /* string */
+       SMC_NLA_LGR_R_VLAN_ID,          /* u8 */
+       SMC_NLA_LGR_R_CONNS_NUM,        /* u32 */
+       __SMC_NLA_LGR_R_MAX,
+       SMC_NLA_LGR_R_MAX = __SMC_NLA_LGR_R_MAX - 1
+};
+
 #endif /* _UAPI_LINUX_SMC_H */

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index c7b1c62..e21d068 100644 (file)
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -274,6 +274,91 @@ errmsg:
        return skb->len;
 }
 
+static int smc_nl_fill_lgr(struct smc_link_group *lgr,
+                          struct sk_buff *skb,
+                          struct netlink_callback *cb)
+{
+       char smc_target[SMC_MAX_PNETID_LEN + 1];
+       struct nlattr *attrs;
+
+       attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCR);
+       if (!attrs)
+               goto errout;
+
+       if (nla_put_u32(skb, SMC_NLA_LGR_R_ID, *((u32 *)&lgr->id)))
+               goto errattr;
+       if (nla_put_u32(skb, SMC_NLA_LGR_R_CONNS_NUM, lgr->conns_num))
+               goto errattr;
+       if (nla_put_u8(skb, SMC_NLA_LGR_R_ROLE, lgr->role))
+               goto errattr;
+       if (nla_put_u8(skb, SMC_NLA_LGR_R_TYPE, lgr->type))
+               goto errattr;
+       if (nla_put_u8(skb, SMC_NLA_LGR_R_VLAN_ID, lgr->vlan_id))
+               goto errattr;
+       snprintf(smc_target, sizeof(smc_target), "%s", lgr->pnet_id);
+       if (nla_put_string(skb, SMC_NLA_LGR_R_PNETID, smc_target))
+               goto errattr;
+
+       nla_nest_end(skb, attrs);
+       return 0;
+errattr:
+       nla_nest_cancel(skb, attrs);
+errout:
+       return -EMSGSIZE;
+}
+
+static int smc_nl_handle_lgr(struct smc_link_group *lgr,
+                            struct sk_buff *skb,
+                            struct netlink_callback *cb)
+{
+       void *nlh;
+
+       nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
+                         &smc_gen_nl_family, NLM_F_MULTI,
+                         SMC_NETLINK_GET_LGR_SMCR);
+       if (!nlh)
+               goto errmsg;
+       if (smc_nl_fill_lgr(lgr, skb, cb))
+               goto errout;
+
+       genlmsg_end(skb, nlh);
+       return 0;
+
+errout:
+       genlmsg_cancel(skb, nlh);
+errmsg:
+       return -EMSGSIZE;
+}
+
+static void smc_nl_fill_lgr_list(struct smc_lgr_list *smc_lgr,
+                                struct sk_buff *skb,
+                                struct netlink_callback *cb)
+{
+       struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
+       struct smc_link_group *lgr;
+       int snum = cb_ctx->pos[0];
+       int num = 0;
+
+       spin_lock_bh(&smc_lgr->lock);
+       list_for_each_entry(lgr, &smc_lgr->list, list) {
+               if (num < snum)
+                       goto next;
+               if (smc_nl_handle_lgr(lgr, skb, cb))
+                       goto errout;
+next:
+               num++;
+       }
+errout:
+       spin_unlock_bh(&smc_lgr->lock);
+       cb_ctx->pos[0] = num;
+}
+
+int smcr_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
+{
+       smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb);
+       return skb->len;
+}
+
 void smc_lgr_cleanup_early(struct smc_connection *conn)
 {
        struct smc_link_group *lgr = conn->lgr;

diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index eaed25d..662315b 100644 (file)
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -415,6 +415,7 @@ struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
 void smcr_link_down_cond(struct smc_link *lnk);
 void smcr_link_down_cond_sched(struct smc_link *lnk);
 int smc_nl_get_sys_info(struct sk_buff *skb, struct netlink_callback *cb);
+int smcr_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb);
 
 static inline struct smc_link_group *smc_get_lgr(struct smc_link *link)
 {

diff --git a/net/smc/smc_netlink.c b/net/smc/smc_netlink.c
index ce06d26..490da56 100644 (file)
--- a/net/smc/smc_netlink.c
+++ b/net/smc/smc_netlink.c
@@ -28,6 +28,11 @@ static const struct genl_ops smc_gen_nl_ops[] = {
                /* can be retrieved by unprivileged users */
                .dumpit = smc_nl_get_sys_info,
        },
+       {
+               .cmd = SMC_NETLINK_GET_LGR_SMCR,
+               /* can be retrieved by unprivileged users */
+               .dumpit = smcr_nl_get_lgr,
+       },
 };
 
 static const struct nla_policy smc_gen_nl_policy[2] = {