File 0002-net-increase-tap-buffer-size.patch of Package xen.481

From: Michal Kubecek <mkubecek@suse.cz>
Date: Fri, 27 Sep 2013 19:05:45 +0200
Subject: net: increase tap buffer size
Patch-mainline: v0.12.0-rc0
Git-commit: 8e0f8e5bf8fd483dd28329055336cf895b74c89f (partial)
References: bnc#840196

Increase size of buffere embedded in struct TAPState to allow
jumbo frames longer then 4096 bytes.

Part of upstream qemu commit

  8e0f8e5b  net: enable IFF_VNET_HDR on tap fds if available

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
---
 tools/qemu-xen-traditional-dir-remote/net.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/tools/qemu-xen-traditional-dir-remote/net.c b/tools/qemu-xen-traditional-dir-remote/net.c
index 2ca85a3..502a691 100644
--- a/tools/qemu-xen-traditional-dir-remote/net.c
+++ b/tools/qemu-xen-traditional-dir-remote/net.c
@@ -693,6 +693,11 @@ static void vmchannel_read(void *opaque, const uint8_t *buf, int size)
 
 #if !defined(_WIN32)
 
+/* Maximum GSO packet size (64k) plus plenty of room for
+ * the ethernet and virtio_net headers
+ */
+#define TAP_BUFSIZE (4096 + 65536)
+
 typedef struct TAPState {
     VLANClientState *vc;
     int fd;
@@ -700,7 +705,7 @@ typedef struct TAPState {
     char down_script[1024];
     char down_script_arg[128];
     char script_arg[1024];
-    uint8_t buf[4096];
+    uint8_t buf[TAP_BUFSIZE];
 } TAPState;
 
 #ifndef CONFIG_STUBDOM
-- 
1.8.1.4