include/: Remove all references to CONFIG_NET_MULTIBUFFER. d_buf in struct net_driver_s is now always a pointer vs. an array.

include/nuttx/net/arp.h

@@ -137,7 +137,7 @@ extern "C"
  ****************************************************************************/
 
 #ifdef CONFIG_NET_ARP_IPIN
-void arp_ipin(struct net_driver_s *dev);
+void arp_ipin(FAR struct net_driver_s **dev);
 #else
 # define arp_ipin(dev)
 #endif
@@ -152,20 +152,20 @@ void arp_ipin(struct net_driver_s *dev);
  *   that we previously sent out, the ARP cache will be filled in with
  *   the values from the ARP reply.  If the incoming ARP packet is an ARP
  *   request for our IP address, an ARP reply packet is created and put
- *   into the d_buf[] buffer.
+ *   into the d_buf buffer.
  *
  *   On entry, this function expects that an ARP packet with a prepended
- *   Ethernet header is present in the d_buf[] buffer and that the length of
+ *   Ethernet header is present in the d_buf buffer and that the length of
  *   the packet is set in the d_len field.
  *
  *   When the function returns, the value of the field d_len indicates whether
  *   the device driver should send out the ARP reply packet or not. If d_len
  *   is zero, no packet should be sent; If d_len is non-zero, it contains the
- *   length of the outbound packet that is present in the d_buf[] buffer.
+ *   length of the outbound packet that is present in the d_buf buffer.
  *
  ****************************************************************************/
 
-void arp_arpin(struct net_driver_s *dev);
+void arp_arpin(FAR struct net_driver_s **dev);
 
 /****************************************************************************
  * Name: arp_out
@@ -183,13 +183,13 @@ void arp_arpin(struct net_driver_s *dev);
  *   beginning of the packet and the function returns.
  *
  *   If no ARP cache entry is found for the destination IIPv4P address, the
- *   packet in the d_buf[] is replaced by an ARP request packet for the
+ *   packet in the d_buf is replaced by an ARP request packet for the
  *   IPv4 address. The IPv4 packet is dropped and it is assumed that the
  *   higher level protocols (e.g., TCP) eventually will retransmit the
  *   dropped packet.
  *
  *   Upon return in either the case, a packet to be sent is present in the
- *   d_buf[] buffer and the d_len field holds the length of the Ethernet
+ *   d_buf buffer and the d_len field holds the length of the Ethernet
  *   frame that should be transmitted.
  *
  ****************************************************************************/

include/nuttx/net/netdev.h

@@ -227,23 +227,19 @@ struct net_driver_s
   net_ipv6addr_t d_ipv6netmask; /* Network IPv6 subnet mask */
 #endif
 
-  /* The d_buf array is used to hold incoming and outgoing packets. The device
-   * driver should place incoming data into this buffer. When sending data,
-   * the device driver should read the link level headers and the TCP/IP
-   * headers from this buffer. The size of the link level headers is
+  /* The d_buf array is used to hold incoming and outgoing packets. The
+   * device driver should place incoming data into this buffer. When sending
+   * data, the device driver should read the link level headers and the
+   * TCP/IP headers from this buffer. The size of the link level headers is
    * configured by the NET_LL_HDRLEN(dev) define.
    *
    * The network will handle only a single buffer for both incoming and
-   * outgoing packets.  However, the driver design may be concurrently send
-   * and filling separate, break-off buffers if CONFIG_NET_MULTIBUFFER is
-   * defined.  That buffer management must be controlled by the driver.
+   * outgoing packets.  However, the driver design may be concurrently
+   * sending and filling separate, break-off buffers.  That buffer
+   * management must be controlled by the driver.
    */
 
-#ifdef CONFIG_NET_MULTIBUFFER
-  uint8_t *d_buf;
-#else
-  uint8_t d_buf[MAX_NET_DEV_MTU + CONFIG_NET_GUARDSIZE];
-#endif
+  FAR uint8_t *d_buf;
 
   /* d_appdata points to the location where application data can be read from
    * or written to in the the packet buffer.

include/nuttx/net/slip.h

@@ -54,7 +54,6 @@
 /* Dependencies:
  *
  *   CONFIG_NET_NOINTS - Required.
- *   CONFIG_NET_MULTIBUFFER - Required.
  *
  * SLIP Configuration:
  *