datapath: Add SCTP support

[sliver-openvswitch.git] / datapath / linux / compat / include / net / sctp / checksum.h

diff --git a/datapath/linux/compat/include/net/sctp/checksum.h b/datapath/linux/compat/include/net/sctp/checksum.h
new file mode 100644 (file)
index 0000000..11fb0b6
--- /dev/null
+++ b/datapath/linux/compat/include/net/sctp/checksum.h
@@ -0,0 +1,31 @@
+#ifndef __SCTP_CHECKSUM_WRAPPER_H
+#define __SCTP_CHECKSUM_WRAPPER_H 1
+
+#include <linux/version.h>
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25)
+#include <net/sctp/sctp.h>
+#else /* LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,25) */
+#include_next <net/sctp/checksum.h>
+#endif
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3,12,0)
+static inline __le32 sctp_compute_cksum(const struct sk_buff *skb,
+                                       unsigned int offset)
+{
+       const struct sk_buff *iter;
+
+       __u32 crc32 = sctp_start_cksum(skb->data + offset,
+                                      skb_headlen(skb) - offset);
+       skb_walk_frags(skb, iter)
+               crc32 = sctp_update_cksum((__u8 *) iter->data,
+                                         skb_headlen(iter), crc32);
+
+       /* Open-code sctp_end_cksum() to avoid a sparse warning due to a bug in
+        * sparse annotations in Linux fixed in 3.10 in commit eee1d5a14 (sctp:
+        * Correct type and usage of sctp_end_cksum()). */
+       return cpu_to_le32(~crc32);
+}
+#endif
+
+#endif