datapath: Conditionally define skb_unclone in datapath compat code

Recent versions of Fedora have skb_unclone included in their
kernels. This patch adds a conditional check into the compat directory so as
not to error out by defining it twice. This allows the latest OVS kernel
module to build on Fedora 19.

Signed-off-by: Kyle Mestery <kmestery@cisco.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

diff --git a/acinclude.m4 b/acinclude.m4
index 717c681..30a4dc6 100644 (file)
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -256,6 +256,7 @@ AC_DEFUN([OVS_CHECK_LINUX_COMPAT], [
   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [consume_skb])
   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_frag_page])
   OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_reset_mac_len])
+  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_unclone])
 
   OVS_GREP_IFELSE([$KSRC/include/linux/string.h], [kmemdup], [],
                   [OVS_GREP_IFELSE([$KSRC/include/linux/slab.h], [kmemdup])])

diff --git a/datapath/linux/compat/include/linux/skbuff.h b/datapath/linux/compat/include/linux/skbuff.h
index c9c103d..461e07c 100644 (file)
--- a/datapath/linux/compat/include/linux/skbuff.h
+++ b/datapath/linux/compat/include/linux/skbuff.h
@@ -252,6 +252,7 @@ static inline void skb_reset_mac_len(struct sk_buff *skb)
 }
 #endif
 
+#ifndef HAVE_SKB_UNCLONE
 static inline int skb_unclone(struct sk_buff *skb, gfp_t pri)
 {
        might_sleep_if(pri & __GFP_WAIT);
@@ -261,6 +262,7 @@ static inline int skb_unclone(struct sk_buff *skb, gfp_t pri)
 
        return 0;
 }
+#endif
 
 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37)
 extern u32 __skb_get_rxhash(struct sk_buff *skb);