netlink: add RX/TX-ring support to netlink diag

Based on AF_PACKET.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 32 insertions, 0 deletions

diff --git a/net/netlink/diag.c b/net/netlink/diag.c
index 5ffb1d1cf402..4e4aa471cd05 100644
--- a/net/netlink/diag.c
+++ b/net/netlink/diag.c
@@ -7,6 +7,34 @@
 
 #include "af_netlink.h"
 
+static int sk_diag_put_ring(struct netlink_ring *ring, int nl_type,
+                            struct sk_buff *nlskb)
+{
+        struct netlink_diag_ring ndr;
+
+        ndr.ndr_block_size = ring->pg_vec_pages << PAGE_SHIFT;
+        ndr.ndr_block_nr   = ring->pg_vec_len;
+        ndr.ndr_frame_size = ring->frame_size;
+        ndr.ndr_frame_nr   = ring->frame_max + 1;
+
+        return nla_put(nlskb, nl_type, sizeof(ndr), &ndr);
+}
+
+static int sk_diag_put_rings_cfg(struct sock *sk, struct sk_buff *nlskb)
+{
+        struct netlink_sock *nlk = nlk_sk(sk);
+        int ret;
+
+        mutex_lock(&nlk->pg_vec_lock);
+        ret = sk_diag_put_ring(&nlk->rx_ring, NETLINK_DIAG_RX_RING, nlskb);
+        if (!ret)
+                ret = sk_diag_put_ring(&nlk->tx_ring, NETLINK_DIAG_TX_RING,
+                                       nlskb);
+        mutex_unlock(&nlk->pg_vec_lock);
+
+        return ret;
+}
+
 static int sk_diag_dump_groups(struct sock *sk, struct sk_buff *nlskb)
 {
         struct netlink_sock *nlk = nlk_sk(sk);
@@ -51,6 +79,10 @@ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
             sock_diag_put_meminfo(sk, skb, NETLINK_DIAG_MEMINFO))
                 goto out_nlmsg_trim;
 
+        if ((req->ndiag_show & NDIAG_SHOW_RING_CFG) &&
+            sk_diag_put_rings_cfg(sk, skb))
+                goto out_nlmsg_trim;
+
         return nlmsg_end(skb, nlh);
 
 out_nlmsg_trim: