lwip: Use custom pbufs for eth and wifi port/netif

components/lwip/CMakeLists.txt

@@ -86,7 +86,8 @@ set(srcs
     "port/esp32/debug/lwip_debug.c"
     "port/esp32/freertos/sys_arch.c"
     "port/esp32/sockets_ext.c"
-    "port/esp32/netif/wlanif.c")
+    "port/esp32/netif/wlanif.c"
+    "port/esp32/netif/esp_pbuf_ref.c")
 
 if(CONFIG_LWIP_PPP_SUPPORT)
     list(APPEND srcs

components/lwip/port/esp32/include/lwipopts.h

@@ -1365,7 +1365,7 @@
 #define ESP_LWIP_SELECT                 1
 #define ESP_LWIP_LOCK                   1
 #define ESP_THREAD_PROTECTION           1
-#define ESP_IP_FORWARD                  1
+#define LWIP_SUPPORT_CUSTOM_PBUF        1
 
 /*
    -----------------------------------------

components/lwip/port/esp32/include/netif/esp_pbuf_ref.h

@@ -0,0 +1,32 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+/**
+ * @file esp_pbuf reference interface file
+ */
+
+#ifndef __LWIP_ESP_PBUF_REF_H__
+#define __LWIP_ESP_PBUF_REF_H__
+
+#include <stddef.h>
+#include "lwip/pbuf.h"
+#include "esp_netif.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief Allocate custom pbuf containing pointer to a private l2-free function
+ *
+ * @note pbuf_free() will deallocate this custom pbuf and call the driver assigned free function
+ */
+struct pbuf* esp_pbuf_allocate(esp_netif_t *esp_netif, void *buffer, size_t len, void *l2_buff);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif //__LWIP_ESP_PBUF_REF_H__

components/lwip/port/esp32/netif/esp_pbuf_ref.c

@@ -0,0 +1,58 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+/**
+ * @file esp_pbuf reference
+ * This file handles lwip custom pbufs interfacing with esp_netif
+ * and the L2 free function esp_netif_free_rx_buffer()
+ */
+
+#include "netif/esp_pbuf_ref.h"
+#include "esp_netif_net_stack.h"
+#include "lwip/mem.h"
+
+/**
+ * @brief Specific pbuf structure for pbufs allocated by ESP netif
+ * of PBUF_REF type
+ */
+typedef struct esp_custom_pbuf
+{
+    struct pbuf_custom p;
+    esp_netif_t *esp_netif;
+    void* l2_buf;
+} esp_custom_pbuf_t;
+
+/**
+ * @brief Free custom pbuf containing the L2 layer buffer allocated in the driver
+ *
+ * @param pbuf Custom pbuf holding the packet passed to lwip input
+ * @note This function called as a custom_free_function() upon pbuf_free()
+ */
+static void esp_pbuf_free(struct pbuf *pbuf)
+{
+    esp_custom_pbuf_t* esp_pbuf = (esp_custom_pbuf_t*)pbuf;
+    esp_netif_free_rx_buffer(esp_pbuf->esp_netif, esp_pbuf->l2_buf);
+    mem_free(pbuf);
+}
+
+
+struct pbuf* esp_pbuf_allocate(esp_netif_t *esp_netif, void *buffer, size_t len, void *l2_buff)
+{
+    struct pbuf *p;
+
+    esp_custom_pbuf_t* esp_pbuf  = mem_malloc(sizeof(esp_custom_pbuf_t));
+    if (esp_pbuf == NULL) {
+        return NULL;
+    }
+    esp_pbuf->p.custom_free_function = esp_pbuf_free;
+    esp_pbuf->esp_netif = esp_netif;
+    esp_pbuf->l2_buf = l2_buff;
+    p = pbuf_alloced_custom(PBUF_RAW, len, PBUF_REF, &esp_pbuf->p, buffer, len);
+    if (p == NULL) {
+        mem_free(esp_pbuf);
+        return NULL;
+    }
+    return p;
+}

components/lwip/port/esp32/netif/ethernetif.c

@@ -52,22 +52,12 @@
 #include "esp_netif.h"
 #include "esp_netif_net_stack.h"
 #include "esp_compiler.h"
+#include "netif/esp_pbuf_ref.h"
 
 /* Define those to better describe your network interface. */
 #define IFNAME0 'e'
 #define IFNAME1 'n'
 
-/**
- * @brief Free resources allocated in L2 layer
- *
- * @param buf memory alloc in L2 layer
- * @note this function is also the callback when invoke pbuf_free
- */
-static void ethernet_free_rx_buf_l2(struct netif *netif, void *buf)
-{
-    free(buf);
-}
-
 /**
  * In this function, the hardware should be initialized.
  * Invoked by ethernetif_init().
@@ -120,11 +110,6 @@ static err_t ethernet_low_level_output(struct netif *netif, struct pbuf *p)
         LWIP_DEBUGF(PBUF_DEBUG, ("low_level_output: pbuf is a list, application may has bug"));
         q = pbuf_alloc(PBUF_RAW_TX, p->tot_len, PBUF_RAM);
         if (q != NULL) {
-#if ESP_LWIP
-            /* This pbuf RAM was not allocated on layer2, no extra free operation needed in pbuf_free */
-            q->l2_owner = NULL;
-            q->l2_buf = NULL;
-#endif
             pbuf_copy(q, p);
         } else {
             return ERR_MEM;
@@ -149,33 +134,30 @@ static err_t ethernet_low_level_output(struct netif *netif, struct pbuf *p)
  * interface. Then the type of the received packet is determined and
  * the appropriate input function is called.
  *
- * @param netif lwip network interface structure for this ethernetif
+ * @param h lwip network interface structure (struct netif) for this ethernetif
  * @param buffer ethernet buffer
  * @param len length of buffer
+ * @param l2_buff Placeholder for a separate L2 buffer. Unused for ethernet interface
  */
-void ethernetif_input(void *h, void *buffer, size_t len, void *eb)
+void ethernetif_input(void *h, void *buffer, size_t len, void *l2_buff)
 {
     struct netif *netif = h;
+    esp_netif_t *esp_netif = esp_netif_get_handle_from_netif_impl(netif);
     struct pbuf *p;
 
     if (unlikely(buffer == NULL || !netif_is_up(netif))) {
         if (buffer) {
-            ethernet_free_rx_buf_l2(netif, buffer);
+            esp_netif_free_rx_buffer(esp_netif, buffer);
         }
         return;
     }
 
-    /* acquire new pbuf, type: PBUF_REF */
-    p = pbuf_alloc(PBUF_RAW, len, PBUF_REF);
+    /* allocate custom pbuf to hold  */
+    p = esp_pbuf_allocate(esp_netif, buffer, len, buffer);
     if (p == NULL) {
-        ethernet_free_rx_buf_l2(netif, buffer);
+        esp_netif_free_rx_buffer(esp_netif, buffer);
         return;
     }
-    p->payload = buffer;
-#if ESP_LWIP
-    p->l2_owner = netif;
-    p->l2_buf = buffer;
-#endif
     /* full packet send to tcpip_thread to process */
     if (unlikely(netif->input(p, netif) != ERR_OK)) {
         LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_input: IP input error\n"));
@@ -228,7 +210,6 @@ err_t ethernetif_init(struct netif *netif)
     netif->output_ip6 = ethip6_output;
 #endif /* LWIP_IPV6 */
     netif->linkoutput = ethernet_low_level_output;
-    netif->l2_buffer_free_notify = ethernet_free_rx_buf_l2;
 
     ethernet_low_level_init(netif);
 

components/lwip/port/esp32/netif/openthreadif.c

@@ -37,11 +37,6 @@ static err_t openthread_output_ip6(struct netif *netif, struct pbuf *p, const st
         LWIP_DEBUGF(PBUF_DEBUG, ("low_level_output: pbuf is a list, application may has bug"));
         q = pbuf_alloc(PBUF_RAW_TX, p->tot_len, PBUF_RAM);
         if (q != NULL) {
-#if ESP_LWIP
-            /* This pbuf RAM was not allocated on layer2, no extra free operation needed in pbuf_free */
-            q->l2_owner = NULL;
-            q->l2_buf = NULL;
-#endif
             pbuf_copy(q, p);
         } else {
             return ERR_MEM;
@@ -84,10 +79,6 @@ void openthread_netif_input(void *h, void *buffer, size_t len, void *eb)
         LWIP_DEBUGF(NETIF_DEBUG, ("Failed to read OpenThread message\n"));
     }
 
-#if ESP_LWIP
-    p->l2_owner = NULL;
-    p->l2_buf = NULL;
-#endif
     /* full packet send to tcpip_thread to process */
     if (unlikely(netif->input(p, netif) != ERR_OK)) {
         LWIP_DEBUGF(NETIF_DEBUG, ("openthread_netif_input: IP input error\n"));
@@ -135,7 +126,6 @@ err_t openthread_netif_init(struct netif *netif)
     netif->output = NULL;
     netif->output_ip6 = openthread_output_ip6;
     netif->mld_mac_filter = openthread_netif_multicast_handler;
-    netif->l2_buffer_free_notify = NULL;
     netif_set_link_up(netif);
 
     return ERR_OK;

components/lwip/port/esp32/netif/wlanif.c

@@ -1,6 +1,6 @@
 /**
  * @file
- * Ethernet Interface Skeleton
+ * Ethernet Interface Skeleton used for WiFi
  *
  */
 
@@ -53,27 +53,14 @@
 #include "esp_netif.h"
 #include "esp_netif_net_stack.h"
 #include "esp_compiler.h"
-
-#ifndef CONFIG_LWIP_L2_TO_L3_COPY
-/**
- * @brief Free resources allocated in L2 layer
- *
- * @param buf memory alloc in L2 layer
- * @note this function is also the callback when invoke pbuf_free
- */
-static void lwip_netif_wifi_free_rx_buffer(struct netif *netif, void *buf)
-{
-    esp_netif_t *esp_netif = esp_netif_get_handle_from_netif_impl(netif);
-    esp_netif_free_rx_buffer(esp_netif, buf);
-}
-#endif
+#include "netif/esp_pbuf_ref.h"
 
 /**
  * In this function, the hardware should be initialized.
- * Called from ethernetif_init().
+ * Called from wlanif_input().
  *
  * @param netif the already initialized lwip network interface structure
- *        for this ethernetif
+ *        for this wlanif
  */
 static void
 low_level_init(struct netif *netif)
@@ -102,9 +89,6 @@ low_level_init(struct netif *netif)
 #endif
 #endif
 
-#ifndef CONFIG_LWIP_L2_TO_L3_COPY
-    netif->l2_buffer_free_notify = lwip_netif_wifi_free_rx_buffer;
-#endif
 }
 
 /**
@@ -112,14 +96,14 @@ low_level_init(struct netif *netif)
  * contained in the pbuf that is passed to the function. This pbuf
  * might be chained.
  *
- * @param netif the lwip network interface structure for this ethernetif
+ * @param netif the lwip network interface structure for this wlanif
  * @param p the MAC packet to send (e.g. IP packet including MAC addresses and type)
  * @return ERR_OK if the packet could be sent
  *         an err_t value if the packet couldn't be sent
  *
  * @note Returning ERR_MEM here if a DMA queue of your MAC is full can lead to
  *       strange results. You might consider waiting for space in the DMA queue
- *       to become availale since the stack doesn't retry to send a packet
+ *       to become available since the stack doesn't retry to send a packet
  *       dropped because of memory failure (except for the TCP timers).
  */
 static err_t
@@ -140,7 +124,6 @@ low_level_output(struct netif *netif, struct pbuf *p)
     LWIP_DEBUGF(PBUF_DEBUG, ("low_level_output: pbuf is a list, application may has bug"));
     q = pbuf_alloc(PBUF_RAW_TX, p->tot_len, PBUF_RAM);
     if (q != NULL) {
-      q->l2_owner = NULL;
       pbuf_copy(q, p);
     } else {
       return ERR_MEM;
@@ -168,18 +151,21 @@ low_level_output(struct netif *netif, struct pbuf *p)
  * interface. Then the type of the received packet is determined and
  * the appropriate input function is called.
  *
- * @param netif the lwip network interface structure for this ethernetif
+ * @param h lwip network interface structure (struct netif) for this ethernetif
+ * @param buffer wlan buffer
+ * @param len length of buffer
+ * @param l2_buff wlan's L2 buffer pointer
  */
 void
-wlanif_input(void *h, void *buffer, size_t len, void* eb)
+wlanif_input(void *h, void *buffer, size_t len, void* l2_buff)
 {
   struct netif * netif = h;
   esp_netif_t *esp_netif = esp_netif_get_handle_from_netif_impl(netif);
   struct pbuf *p;
 
   if(unlikely(!buffer || !netif_is_up(netif))) {
-    if (eb) {
-      esp_netif_free_rx_buffer(esp_netif, eb);
+    if (l2_buff) {
+      esp_netif_free_rx_buffer(esp_netif, l2_buff);
     }
     return;
   }
@@ -187,26 +173,23 @@ wlanif_input(void *h, void *buffer, size_t len, void* eb)
 #ifdef CONFIG_LWIP_L2_TO_L3_COPY
   p = pbuf_alloc(PBUF_RAW, len, PBUF_RAM);
   if (p == NULL) {
-      esp_netif_free_rx_buffer(esp_netif, eb);
+    esp_netif_free_rx_buffer(esp_netif, l2_buff);
     return;
   }
-  p->l2_owner = NULL;
   memcpy(p->payload, buffer, len);
-  esp_netif_free_rx_buffer(esp_netif, eb);
+  esp_netif_free_rx_buffer(esp_netif, l2_buff);
 #else
-  p = pbuf_alloc(PBUF_RAW, len, PBUF_REF);
-  if (p == NULL){
-    esp_netif_free_rx_buffer(esp_netif, eb);
+  p = esp_pbuf_allocate(esp_netif, buffer, len, l2_buff);
+  if (p == NULL) {
+    esp_netif_free_rx_buffer(esp_netif, l2_buff);
     return;
   }
-  p->payload = buffer;
-  p->l2_owner = netif;
-  p->l2_buf = eb;
-#endif /* CONFIG_LWIP_L2_TO_L3_COPY */
+
+#endif
 
   /* full packet send to tcpip_thread to process */
   if (unlikely(netif->input(p, netif) != ERR_OK)) {
-    LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_input: IP input error\n"));
+    LWIP_DEBUGF(NETIF_DEBUG, ("wlanif_input: IP input error\n"));
     pbuf_free(p);
   }
 
@@ -219,7 +202,7 @@ wlanif_input(void *h, void *buffer, size_t len, void* eb)
  *
  * This function should be passed as a parameter to netif_add().
  *
- * @param netif the lwip network interface structure for this ethernetif
+ * @param netif the lwip network interface structure for this wlanif
  * @return ERR_OK if the loopif is initialized
  *         ERR_MEM if private data couldn't be allocated
  *         any other err_t on error