tftp: get the tftp block size from config file and from the environment

Increasing the block size is useful if CONFIG_IP_DEFRAG is used. Howerver, the last fragments in a burst may overflow the receiving ethernet, so the default is left at 1468, with thre new CONFIG_TFTP_BLOCKSIZE for config files. Further, "tftpblocksize" can be set in the environment. Signed-off-by: Alessandro Rubini <rubini@gnudd.com> Signed-off-by: Ben Warren <biggerbadderben@gmail.com>

tftp: get the tftp block size from config file and from the environment
Increasing the block size is useful if CONFIG_IP_DEFRAG is used. Howerver, the last fragments in a burst may overflow the receiving ethernet, so the default is left at 1468, with thre new CONFIG_TFTP_BLOCKSIZE for config files. Further, "tftpblocksize" can be set in the environment. Signed-off-by: Alessandro Rubini <rubini@gnudd.com> Signed-off-by: Ben Warren <biggerbadderben@gmail.com>
Alessandro Rubini · Ben Warren
1 parent 5cfaa4e54d
Showing 1 changed file with 11 additions and 2 deletions Side-by-side Diff
net/tftp.c
@@ -84,8 +84,14 @@
 /* 512 is poor choice for ethernet, MTU is typically 1500.
  * Minus eth.hdrs thats 1468.  Can get 2x better throughput with
  * almost-MTU block sizes.  At least try... fall back to 512 if need be.
+ * (but those using CONFIG_IP_DEFRAG may want to set a larger block in cfg file)
  */
+#ifdef CONFIG_TFTP_BLOCKSIZE
+#define TFTP_MTU_BLOCKSIZE CONFIG_TFTP_BLOCKSIZE
+#else
 #define TFTP_MTU_BLOCKSIZE 1468
+#endif
+
 static unsigned short TftpBlkSize=TFTP_BLOCK_SIZE;
 static unsigned short TftpBlkSizeOption=TFTP_MTU_BLOCKSIZE;
  
  
@@ -466,9 +472,12 @@
 void
 TftpStart (void)
 {
-#ifdef CONFIG_TFTP_PORT
 	char *ep;             /* Environment pointer */
-#endif
+
+	/* Allow the user to choose tftpblocksize */
+	if ((ep = getenv("tftpblocksize")) != NULL)
+		TftpBlkSizeOption = simple_strtol(ep, NULL, 10);
+	debug("tftp block size is %i\n", TftpBlkSizeOption);
  
 	TftpServerIP = NetServerIP;
 	if (BootFile[0] == '\0') {
...	...	@@ -84,8 +84,14 @@
84	84	/* 512 is poor choice for ethernet, MTU is typically 1500.
85	85	* Minus eth.hdrs thats 1468. Can get 2x better throughput with
86	86	* almost-MTU block sizes. At least try... fall back to 512 if need be.
	87	+ * (but those using CONFIG_IP_DEFRAG may want to set a larger block in cfg file)
87	88	*/
	89	+#ifdef CONFIG_TFTP_BLOCKSIZE
	90	+#define TFTP_MTU_BLOCKSIZE CONFIG_TFTP_BLOCKSIZE
	91	+#else
88	92	#define TFTP_MTU_BLOCKSIZE 1468
	93	+#endif
	94	+
89	95	static unsigned short TftpBlkSize=TFTP_BLOCK_SIZE;
90	96	static unsigned short TftpBlkSizeOption=TFTP_MTU_BLOCKSIZE;
91	97
92	98
...	...	@@ -466,9 +472,12 @@
466	472	void
467	473	TftpStart (void)
468	474	{
469		-#ifdef CONFIG_TFTP_PORT
470	475	char ep; / Environment pointer */
471		-#endif
	476	+
	477	+ /* Allow the user to choose tftpblocksize */
	478	+ if ((ep = getenv("tftpblocksize")) != NULL)
	479	+ TftpBlkSizeOption = simple_strtol(ep, NULL, 10);
	480	+ debug("tftp block size is %i\n", TftpBlkSizeOption);
472	481
473	482	TftpServerIP = NetServerIP;
474	483	if (BootFile[0] == '\0') {