rtnl: allow to specify number of rx and tx queues on device creation

This patch introduces IFLA_NUM_TX_QUEUES and IFLA_NUM_RX_QUEUES by
which userspace can set number of rx and/or tx queues to be allocated
for newly created netdevice.
This overrides ops->get_num_[tr]x_queues()

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 15 insertions, 2 deletions

diff --git a/include/linux/if_link.h b/include/linux/if_link.h
index f715750d0b87..ac173bd2ab65 100644
--- a/include/linux/if_link.h
+++ b/include/linux/if_link.h
@@ -140,6 +140,8 @@ enum {
         IFLA_EXT_MASK,          /* Extended info mask, VFs, etc */
         IFLA_PROMISCUITY,       /* Promiscuity count: > 0 means acts PROMISC */
 #define IFLA_PROMISCUITY IFLA_PROMISCUITY
+        IFLA_NUM_TX_QUEUES,
+        IFLA_NUM_RX_QUEUES,
         __IFLA_MAX
 };
 
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index db5a8ad8a79b..5bb1ebca2eb0 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -771,6 +771,8 @@ static noinline size_t if_nlmsg_size(const struct net_device *dev,
                + nla_total_size(4) /* IFLA_LINK */
                + nla_total_size(4) /* IFLA_MASTER */
                + nla_total_size(4) /* IFLA_PROMISCUITY */
+               + nla_total_size(4) /* IFLA_NUM_TX_QUEUES */
+               + nla_total_size(4) /* IFLA_NUM_RX_QUEUES */
                + nla_total_size(1) /* IFLA_OPERSTATE */
                + nla_total_size(1) /* IFLA_LINKMODE */
                + nla_total_size(ext_filter_mask
@@ -889,6 +891,8 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
             nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
             nla_put_u32(skb, IFLA_GROUP, dev->group) ||
             nla_put_u32(skb, IFLA_PROMISCUITY, dev->promiscuity) ||
+            nla_put_u32(skb, IFLA_NUM_TX_QUEUES, dev->num_tx_queues) ||
+            nla_put_u32(skb, IFLA_NUM_RX_QUEUES, dev->num_rx_queues) ||
             (dev->ifindex != dev->iflink &&
              nla_put_u32(skb, IFLA_LINK, dev->iflink)) ||
             (dev->master &&
@@ -1106,6 +1110,8 @@ const struct nla_policy ifla_policy[IFLA_MAX+1] = {
         [IFLA_AF_SPEC]          = { .type = NLA_NESTED },
         [IFLA_EXT_MASK]         = { .type = NLA_U32 },
         [IFLA_PROMISCUITY]      = { .type = NLA_U32 },
+        [IFLA_NUM_TX_QUEUES]    = { .type = NLA_U32 },
+        [IFLA_NUM_RX_QUEUES]    = { .type = NLA_U32 },
 };
 EXPORT_SYMBOL(ifla_policy);
 
@@ -1627,9 +1633,14 @@ struct net_device *rtnl_create_link(struct net *src_net, struct net *net,
         unsigned int num_tx_queues = 1;
         unsigned int num_rx_queues = 1;
 
-        if (ops->get_num_tx_queues)
+        if (tb[IFLA_NUM_TX_QUEUES])
+                num_tx_queues = nla_get_u32(tb[IFLA_NUM_TX_QUEUES]);
+        else if (ops->get_num_tx_queues)
                 num_tx_queues = ops->get_num_tx_queues();
-        if (ops->get_num_rx_queues)
+
+        if (tb[IFLA_NUM_RX_QUEUES])
+                num_rx_queues = nla_get_u32(tb[IFLA_NUM_RX_QUEUES]);
+        else if (ops->get_num_rx_queues)
                 num_rx_queues = ops->get_num_rx_queues();
 
         err = -ENOMEM;