dcbnl: more informed return values for new dcbnl routines

More accurate return values for the following (new) dcbnl routines:
dcbnl_getdcbx()
dcbnl_setdcbx()
dcbnl_getfeatcfg()
dcbnl_setfeatcfg()

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

1 files changed, 37 insertions, 44 deletions

diff --git a/net/dcb/dcbnl.c b/net/dcb/dcbnl.c
index ff3c12d2cd72..9399af565715 100644
--- a/net/dcb/dcbnl.c
+++ b/net/dcb/dcbnl.c
@@ -1286,10 +1286,10 @@ nlmsg_failure:
 static int dcbnl_getdcbx(struct net_device *netdev, struct nlattr **tb,
                          u32 pid, u32 seq, u16 flags)
 {
-        int ret = -EINVAL;
+        int ret;
 
         if (!netdev->dcbnl_ops->getdcbx)
-                return ret;
+                return -EOPNOTSUPP;
 
         ret = dcbnl_reply(netdev->dcbnl_ops->getdcbx(netdev), RTM_GETDCB,
                           DCB_CMD_GDCBX, DCB_ATTR_DCBX, pid, seq, flags);
@@ -1300,11 +1300,14 @@ static int dcbnl_getdcbx(struct net_device *netdev, struct nlattr **tb,
 static int dcbnl_setdcbx(struct net_device *netdev, struct nlattr **tb,
                          u32 pid, u32 seq, u16 flags)
 {
-        int ret = -EINVAL;
+        int ret;
         u8 value;
 
-        if (!tb[DCB_ATTR_DCBX] || !netdev->dcbnl_ops->setdcbx)
-                return ret;
+        if (!netdev->dcbnl_ops->setdcbx)
+                return -EOPNOTSUPP;
+
+        if (!tb[DCB_ATTR_DCBX])
+                return -EINVAL;
 
         value = nla_get_u8(tb[DCB_ATTR_DCBX]);
 
@@ -1323,23 +1326,23 @@ static int dcbnl_getfeatcfg(struct net_device *netdev, struct nlattr **tb,
         struct dcbmsg *dcb;
         struct nlattr *data[DCB_FEATCFG_ATTR_MAX + 1], *nest;
         u8 value;
-        int ret = -EINVAL;
-        int i;
+        int ret, i;
         int getall = 0;
 
-        if (!tb[DCB_ATTR_FEATCFG] || !netdev->dcbnl_ops->getfeatcfg)
-                return ret;
+        if (!netdev->dcbnl_ops->getfeatcfg)
+                return -EOPNOTSUPP;
+
+        if (!tb[DCB_ATTR_FEATCFG])
+                return -EINVAL;
 
         ret = nla_parse_nested(data, DCB_FEATCFG_ATTR_MAX, tb[DCB_ATTR_FEATCFG],
                                dcbnl_featcfg_nest);
-        if (ret) {
-                ret = -EINVAL;
+        if (ret)
                 goto err_out;
-        }
 
         dcbnl_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
         if (!dcbnl_skb) {
-                ret = -EINVAL;
+                ret = -ENOBUFS;
                 goto err_out;
         }
 
@@ -1351,8 +1354,8 @@ static int dcbnl_getfeatcfg(struct net_device *netdev, struct nlattr **tb,
 
         nest = nla_nest_start(dcbnl_skb, DCB_ATTR_FEATCFG);
         if (!nest) {
-                ret = -EINVAL;
-                goto err;
+                ret = -EMSGSIZE;
+                goto nla_put_failure;
         }
 
         if (data[DCB_FEATCFG_ATTR_ALL])
@@ -1363,30 +1366,22 @@ static int dcbnl_getfeatcfg(struct net_device *netdev, struct nlattr **tb,
                         continue;
 
                 ret = netdev->dcbnl_ops->getfeatcfg(netdev, i, &value);
-                if (!ret) {
+                if (!ret)
                         ret = nla_put_u8(dcbnl_skb, i, value);
 
-                        if (ret) {
-                                nla_nest_cancel(dcbnl_skb, nest);
-                                ret = -EINVAL;
-                                goto err;
-                        }
-                } else
-                        goto err;
+                if (ret) {
+                        nla_nest_cancel(dcbnl_skb, nest);
+                        goto nla_put_failure;
+                }
         }
         nla_nest_end(dcbnl_skb, nest);
 
         nlmsg_end(dcbnl_skb, nlh);
 
-        ret = rtnl_unicast(dcbnl_skb, &init_net, pid);
-        if (ret) {
-                ret = -EINVAL;
-                goto err_out;
-        }
-
-        return 0;
+        return rtnl_unicast(dcbnl_skb, &init_net, pid);
+nla_put_failure:
+        nlmsg_cancel(dcbnl_skb, nlh);
 nlmsg_failure:
-err:
         kfree_skb(dcbnl_skb);
 err_out:
         return ret;
@@ -1396,20 +1391,20 @@ static int dcbnl_setfeatcfg(struct net_device *netdev, struct nlattr **tb,
                             u32 pid, u32 seq, u16 flags)
 {
         struct nlattr *data[DCB_FEATCFG_ATTR_MAX + 1];
-        int ret = -EINVAL;
+        int ret, i;
         u8 value;
-        int i;
 
-        if (!tb[DCB_ATTR_FEATCFG] || !netdev->dcbnl_ops->setfeatcfg)
-                return ret;
+        if (!netdev->dcbnl_ops->setfeatcfg)
+                return -ENOTSUPP;
+
+        if (!tb[DCB_ATTR_FEATCFG])
+                return -EINVAL;
 
         ret = nla_parse_nested(data, DCB_FEATCFG_ATTR_MAX, tb[DCB_ATTR_FEATCFG],
                                dcbnl_featcfg_nest);
 
-        if (ret) {
-                ret = -EINVAL;
+        if (ret)
                 goto err;
-        }
 
         for (i = DCB_FEATCFG_ATTR_ALL+1; i <= DCB_FEATCFG_ATTR_MAX; i++) {
                 if (data[i] == NULL)
@@ -1420,14 +1415,12 @@ static int dcbnl_setfeatcfg(struct net_device *netdev, struct nlattr **tb,
                 ret = netdev->dcbnl_ops->setfeatcfg(netdev, i, value);
 
                 if (ret)
-                        goto operr;
+                        goto err;
         }
-
-operr:
-        ret = dcbnl_reply(!!ret, RTM_SETDCB, DCB_CMD_SFEATCFG,
-                          DCB_ATTR_FEATCFG, pid, seq, flags);
-
 err:
+        dcbnl_reply(ret, RTM_SETDCB, DCB_CMD_SFEATCFG, DCB_ATTR_FEATCFG,
+                    pid, seq, flags);
+
         return ret;
 }