dcbnl: add support for retrieving peer configuration - cee

This patch adds the support for retrieving the remote or peer DCBX
configuration via dcbnl for embedded DCBX stacks supporting the CEE DCBX
standard.

Signed-off-by: Shmulik Ravid <shmulikr@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 155 insertions, 4 deletions

diff --git a/include/linux/dcbnl.h b/include/linux/dcbnl.h
index 2542685f8b3e..a3680a16718f 100644
--- a/include/linux/dcbnl.h
+++ b/include/linux/dcbnl.h
@@ -87,6 +87,45 @@ struct ieee_pfc {
         __u64   indications[IEEE_8021QAZ_MAX_TCS];
 };
 
+/* CEE DCBX std supported values */
+#define CEE_DCBX_MAX_PGS        8
+#define CEE_DCBX_MAX_PRIO       8
+
+/**
+ * struct cee_pg - CEE Prioity-Group managed object
+ *
+ * @willing: willing bit in the PG tlv
+ * @error: error bit in the PG tlv
+ * @pg_en: enable bit of the PG feature
+ * @tcs_supported: number of traffic classes supported
+ * @pg_bw: bandwidth percentage for each priority group
+ * @prio_pg: priority to PG mapping indexed by priority
+ */
+struct cee_pg {
+        __u8    willing;
+        __u8    error;
+        __u8    pg_en;
+        __u8    tcs_supported;
+        __u8    pg_bw[CEE_DCBX_MAX_PGS];
+        __u8    prio_pg[CEE_DCBX_MAX_PGS];
+};
+
+/**
+ * struct cee_pfc - CEE PFC managed object
+ *
+ * @willing: willing bit in the PFC tlv
+ * @error: error bit in the PFC tlv
+ * @pfc_en: bitmap indicating pfc enabled traffic classes
+ * @tcs_supported: number of traffic classes supported
+ */
+struct cee_pfc {
+        __u8    willing;
+        __u8    error;
+        __u8    pfc_en;
+        __u8    tcs_supported;
+};
+
+
 /* This structure contains the IEEE 802.1Qaz APP managed object. This
  * object is also used for the CEE std as well. There is no difference
  * between the objects.
@@ -158,6 +197,7 @@ struct dcbmsg {
  * @DCB_CMD_SDCBX: set DCBX engine configuration
  * @DCB_CMD_GFEATCFG: get DCBX features flags
  * @DCB_CMD_SFEATCFG: set DCBX features negotiation flags
+ * @DCB_CMD_CEE_GET: get CEE aggregated configuration
  */
 enum dcbnl_commands {
         DCB_CMD_UNDEFINED,
@@ -200,6 +240,8 @@ enum dcbnl_commands {
         DCB_CMD_GFEATCFG,
         DCB_CMD_SFEATCFG,
 
+        DCB_CMD_CEE_GET,
+
         __DCB_CMD_ENUM_MAX,
         DCB_CMD_MAX = __DCB_CMD_ENUM_MAX - 1,
 };
@@ -222,6 +264,7 @@ enum dcbnl_commands {
  * @DCB_ATTR_IEEE: IEEE 802.1Qaz supported attributes (NLA_NESTED)
  * @DCB_ATTR_DCBX: DCBX engine configuration in the device (NLA_U8)
  * @DCB_ATTR_FEATCFG: DCBX features flags (NLA_NESTED)
+ * @DCB_ATTR_CEE: CEE std supported attributes (NLA_NESTED)
  */
 enum dcbnl_attrs {
         DCB_ATTR_UNDEFINED,
@@ -245,6 +288,9 @@ enum dcbnl_attrs {
         DCB_ATTR_DCBX,
         DCB_ATTR_FEATCFG,
 
+        /* CEE nested attributes */
+        DCB_ATTR_CEE,
+
         __DCB_ATTR_ENUM_MAX,
         DCB_ATTR_MAX = __DCB_ATTR_ENUM_MAX - 1,
 };
@@ -280,6 +326,31 @@ enum ieee_attrs_app {
 #define DCB_ATTR_IEEE_APP_MAX (__DCB_ATTR_IEEE_APP_MAX - 1)
 
 /**
+ * enum cee_attrs - CEE DCBX get attributes
+ *
+ * @DCB_ATTR_CEE_UNSPEC: unspecified
+ * @DCB_ATTR_CEE_PEER_PG: peer PG configuration - get only
+ * @DCB_ATTR_CEE_PEER_PFC: peer PFC configuration - get only
+ * @DCB_ATTR_CEE_PEER_APP: peer APP tlv - get only
+ */
+enum cee_attrs {
+        DCB_ATTR_CEE_UNSPEC,
+        DCB_ATTR_CEE_PEER_PG,
+        DCB_ATTR_CEE_PEER_PFC,
+        DCB_ATTR_CEE_PEER_APP_TABLE,
+        __DCB_ATTR_CEE_MAX
+};
+#define DCB_ATTR_CEE_MAX (__DCB_ATTR_CEE_MAX - 1)
+
+enum peer_app_attr {
+        DCB_ATTR_CEE_PEER_APP_UNSPEC,
+        DCB_ATTR_CEE_PEER_APP_INFO,
+        DCB_ATTR_CEE_PEER_APP,
+        __DCB_ATTR_CEE_PEER_APP_MAX
+};
+#define DCB_ATTR_CEE_PEER_APP_MAX (__DCB_ATTR_CEE_PEER_APP_MAX - 1)
+
+/**
  * enum dcbnl_pfc_attrs - DCB Priority Flow Control user priority nested attrs
  *
  * @DCB_PFC_UP_ATTR_UNDEFINED: unspecified attribute to catch errors
diff --git a/include/net/dcbnl.h b/include/net/dcbnl.h
index 7b7180e692ef..e5983c9053dc 100644
--- a/include/net/dcbnl.h
+++ b/include/net/dcbnl.h
@@ -84,6 +84,9 @@ struct dcbnl_rtnl_ops {
                                u16 *);
         int (*peer_getapptable)(struct net_device *, struct dcb_app *);
 
+        /* CEE peer */
+        int (*cee_peer_getpg) (struct net_device *, struct cee_pg *);
+        int (*cee_peer_getpfc) (struct net_device *, struct cee_pfc *);
 };
 
 #endif /* __NET_DCBNL_H__ */
diff --git a/net/dcb/dcbnl.c b/net/dcb/dcbnl.c
index 2e6dcf2967e2..d8b4f725b778 100644
--- a/net/dcb/dcbnl.c
+++ b/net/dcb/dcbnl.c
@@ -1224,7 +1224,9 @@ err:
         return err;
 }
 
-static int dcbnl_build_peer_app(struct net_device *netdev, struct sk_buff* skb)
+static int dcbnl_build_peer_app(struct net_device *netdev, struct sk_buff* skb,
+                                int app_nested_type, int app_info_type,
+                                int app_entry_type)
 {
         struct dcb_peer_app_info info;
         struct dcb_app *table = NULL;
@@ -1256,12 +1258,15 @@ static int dcbnl_build_peer_app(struct net_device *netdev, struct sk_buff* skb)
                  */
                 err = -EMSGSIZE;
 
-                app = nla_nest_start(skb, DCB_ATTR_IEEE_PEER_APP);
+                app = nla_nest_start(skb, app_nested_type);
                 if (!app)
                         goto nla_put_failure;
 
+                if (app_info_type)
+                        NLA_PUT(skb, app_info_type, sizeof(info), &info);
+
                 for (i = 0; i < app_count; i++)
-                        NLA_PUT(skb, DCB_ATTR_IEEE_APP, sizeof(struct dcb_app),
+                        NLA_PUT(skb, app_entry_type, sizeof(struct dcb_app),
                                 &table[i]);
 
                 nla_nest_end(skb, app);
@@ -1352,7 +1357,10 @@ static int dcbnl_ieee_get(struct net_device *netdev, struct nlattr **tb,
         }
 
         if (ops->peer_getappinfo && ops->peer_getapptable) {
-                err = dcbnl_build_peer_app(netdev, skb);
+                err = dcbnl_build_peer_app(netdev, skb,
+                                           DCB_ATTR_IEEE_PEER_APP,
+                                           DCB_ATTR_IEEE_APP_UNSPEC,
+                                           DCB_ATTR_IEEE_APP);
                 if (err)
                         goto nla_put_failure;
         }
@@ -1510,6 +1518,71 @@ err:
         return ret;
 }
 
+/* Handle CEE DCBX GET commands. */
+static int dcbnl_cee_get(struct net_device *netdev, struct nlattr **tb,
+                         u32 pid, u32 seq, u16 flags)
+{
+        struct sk_buff *skb;
+        struct nlmsghdr *nlh;
+        struct dcbmsg *dcb;
+        struct nlattr *cee;
+        const struct dcbnl_rtnl_ops *ops = netdev->dcbnl_ops;
+        int err;
+
+        if (!ops)
+                return -EOPNOTSUPP;
+
+        skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+        if (!skb)
+                return -ENOBUFS;
+
+        nlh = NLMSG_NEW(skb, pid, seq, RTM_GETDCB, sizeof(*dcb), flags);
+
+        dcb = NLMSG_DATA(nlh);
+        dcb->dcb_family = AF_UNSPEC;
+        dcb->cmd = DCB_CMD_CEE_GET;
+
+        NLA_PUT_STRING(skb, DCB_ATTR_IFNAME, netdev->name);
+
+        cee = nla_nest_start(skb, DCB_ATTR_CEE);
+        if (!cee)
+                goto nla_put_failure;
+
+        /* get peer info if available */
+        if (ops->cee_peer_getpg) {
+                struct cee_pg pg;
+                err = ops->cee_peer_getpg(netdev, &pg);
+                if (!err)
+                        NLA_PUT(skb, DCB_ATTR_CEE_PEER_PG, sizeof(pg), &pg);
+        }
+
+        if (ops->cee_peer_getpfc) {
+                struct cee_pfc pfc;
+                err = ops->cee_peer_getpfc(netdev, &pfc);
+                if (!err)
+                        NLA_PUT(skb, DCB_ATTR_CEE_PEER_PFC, sizeof(pfc), &pfc);
+        }
+
+        if (ops->peer_getappinfo && ops->peer_getapptable) {
+                err = dcbnl_build_peer_app(netdev, skb,
+                                           DCB_ATTR_CEE_PEER_APP_TABLE,
+                                           DCB_ATTR_CEE_PEER_APP_INFO,
+                                           DCB_ATTR_CEE_PEER_APP);
+                if (err)
+                        goto nla_put_failure;
+        }
+
+        nla_nest_end(skb, cee);
+        nlmsg_end(skb, nlh);
+
+        return rtnl_unicast(skb, &init_net, pid);
+nla_put_failure:
+        nlmsg_cancel(skb, nlh);
+nlmsg_failure:
+        kfree_skb(skb);
+        return -1;
+}
+
 static int dcb_doit(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
         struct net *net = sock_net(skb->sk);
@@ -1639,6 +1712,10 @@ static int dcb_doit(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
                 ret = dcbnl_setfeatcfg(netdev, tb, pid, nlh->nlmsg_seq,
                                        nlh->nlmsg_flags);
                 goto out;
+        case DCB_CMD_CEE_GET:
+                ret = dcbnl_cee_get(netdev, tb, pid, nlh->nlmsg_seq,
+                                    nlh->nlmsg_flags);
+                goto out;
         default:
                 goto errout;
         }