From 2a342d24240625fdf4005147525a90ba5cb847cf Mon Sep 17 00:00:00 2001
From: Zhe Weng <wengzhe@xiaomi.com>
Date: Wed, 27 Mar 2024 18:52:54 +0800
Subject: [PATCH] net/netdev: Add netdev_iob_clone helper

Signed-off-by: Zhe Weng <wengzhe@xiaomi.com>
---
 include/nuttx/net/netdev.h   | 14 +++++++++++++
 net/ipforward/ipv4_forward.c | 13 ++----------
 net/ipforward/ipv6_forward.c | 13 ++----------
 net/netdev/netdev_iob.c      | 38 ++++++++++++++++++++++++++++++++++++
 4 files changed, 56 insertions(+), 22 deletions(-)

diff --git a/include/nuttx/net/netdev.h b/include/nuttx/net/netdev.h
index 594e03409a..97cea719b7 100644
--- a/include/nuttx/net/netdev.h
+++ b/include/nuttx/net/netdev.h
@@ -1038,6 +1038,20 @@ void netdev_iob_clear(FAR struct net_driver_s *dev);
 
 void netdev_iob_release(FAR struct net_driver_s *dev);
 
+/****************************************************************************
+ * Name: netdev_iob_clone
+ *
+ * Description:
+ *   Backup the current iob buffer for a given NIC by cloning it.
+ *
+ * Assumptions:
+ *   The caller has locked the network.
+ *
+ ****************************************************************************/
+
+FAR struct iob_s *netdev_iob_clone(FAR struct net_driver_s *dev,
+                                   bool throttled);
+
 /****************************************************************************
  * Name: netdev_ipv6_add/del
  *
diff --git a/net/ipforward/ipv4_forward.c b/net/ipforward/ipv4_forward.c
index ac608681ed..11ffb88613 100644
--- a/net/ipforward/ipv4_forward.c
+++ b/net/ipforward/ipv4_forward.c
@@ -364,22 +364,13 @@ static int ipv4_forward_callback(FAR struct net_driver_s *fwddev,
     {
       /* Backup the forward IP packet */
 
-      iob = iob_tryalloc(true);
+      iob = netdev_iob_clone(dev, true);
       if (iob == NULL)
         {
-          nerr("ERROR: iob alloc failed when forward broadcast\n");
+          nerr("ERROR: IOB clone failed when forwarding broadcast.\n");
           return -ENOMEM;
         }
 
-      iob_reserve(iob, CONFIG_NET_LL_GUARDSIZE);
-      ret = iob_clone_partial(dev->d_iob, dev->d_iob->io_pktlen, 0,
-                              iob, 0, true, false);
-      if (ret < 0)
-        {
-          iob_free_chain(iob);
-          return ret;
-        }
-
       /* Recover the pointer to the IPv4 header in the receiving device's
        * d_buf.
        */
diff --git a/net/ipforward/ipv6_forward.c b/net/ipforward/ipv6_forward.c
index 48698a2e7e..769fce8138 100644
--- a/net/ipforward/ipv6_forward.c
+++ b/net/ipforward/ipv6_forward.c
@@ -491,22 +491,13 @@ static int ipv6_forward_callback(FAR struct net_driver_s *fwddev,
     {
       /* Backup the forward IP packet */
 
-      iob = iob_tryalloc(true);
+      iob = netdev_iob_clone(dev, true);
       if (iob == NULL)
         {
-          nerr("ERROR: iob alloc failed when forward broadcast\n");
+          nerr("ERROR: IOB clone failed when forwarding broadcast.\n");
           return -ENOMEM;
         }
 
-      iob_reserve(iob, CONFIG_NET_LL_GUARDSIZE);
-      ret = iob_clone_partial(dev->d_iob, dev->d_iob->io_pktlen, 0,
-                              iob, 0, true, false);
-      if (ret < 0)
-        {
-          iob_free_chain(iob);
-          return ret;
-        }
-
       /* Recover the pointer to the IPv6 header in the receiving device's
        * d_buf.
        */
diff --git a/net/netdev/netdev_iob.c b/net/netdev/netdev_iob.c
index 1c4886b209..999f7776e3 100644
--- a/net/netdev/netdev_iob.c
+++ b/net/netdev/netdev_iob.c
@@ -153,3 +153,41 @@ void netdev_iob_release(FAR struct net_driver_s *dev)
 
   dev->d_buf = NULL;
 }
+
+/****************************************************************************
+ * Name: netdev_iob_clone
+ *
+ * Description:
+ *   Backup the current iob buffer for a given NIC by cloning it.
+ *
+ * Assumptions:
+ *   The caller has locked the network.
+ *
+ ****************************************************************************/
+
+FAR struct iob_s *netdev_iob_clone(FAR struct net_driver_s *dev,
+                                   bool throttled)
+{
+  FAR struct iob_s *iob;
+  int ret;
+
+  iob = iob_tryalloc(throttled);
+  if (iob == NULL)
+    {
+      nwarn("WARNING: IOB alloc failed for dev %s!\n", dev->d_ifname);
+      return NULL;
+    }
+
+  iob_reserve(iob, CONFIG_NET_LL_GUARDSIZE);
+  ret = iob_clone_partial(dev->d_iob, dev->d_iob->io_pktlen, 0,
+                          iob, 0, throttled, false);
+  if (ret < 0)
+    {
+      iob_free_chain(iob);
+      nwarn("WARNING: IOB clone failed for dev %s, ret=%d!\n",
+            dev->d_ifname, ret);
+      return NULL;
+    }
+
+  return iob;
+}