Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / include / net / sctp / checksum.h
diff --git a/kernel/include/net/sctp/checksum.h b/kernel/include/net/sctp/checksum.h
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@@ -0,0 +1,78 @@
+/* SCTP kernel reference Implementation
+ * Copyright (c) 1999-2001 Motorola, Inc.
+ * Copyright (c) 2001-2003 International Business Machines, Corp.
+ *
+ * This file is part of the SCTP kernel reference Implementation
+ *
+ * SCTP Checksum functions
+ *
+ * The SCTP reference implementation is free software;
+ * you can redistribute it and/or modify it under the terms of
+ * the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * The SCTP reference implementation is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied
+ *                 ************************
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU CC; see the file COPYING.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ *    lksctp developers <linux-sctp@vger.kernel.org>
+ *
+ * Written or modified by:
+ *    Dinakaran Joseph
+ *    Jon Grimm <jgrimm@us.ibm.com>
+ *    Sridhar Samudrala <sri@us.ibm.com>
+ *
+ * Rewritten to use libcrc32c by:
+ *    Vlad Yasevich <vladislav.yasevich@hp.com>
+ */
+
+#ifndef __sctp_checksum_h__
+#define __sctp_checksum_h__
+
+#include <linux/types.h>
+#include <net/sctp/sctp.h>
+#include <linux/crc32c.h>
+#include <linux/crc32.h>
+
+static inline __wsum sctp_csum_update(const void *buff, int len, __wsum sum)
+{
+       /* This uses the crypto implementation of crc32c, which is either
+        * implemented w/ hardware support or resolves to __crc32c_le().
+        */
+       return crc32c(sum, buff, len);
+}
+
+static inline __wsum sctp_csum_combine(__wsum csum, __wsum csum2,
+                                      int offset, int len)
+{
+       return __crc32c_le_combine(csum, csum2, len);
+}
+
+static inline __le32 sctp_compute_cksum(const struct sk_buff *skb,
+                                       unsigned int offset)
+{
+       struct sctphdr *sh = sctp_hdr(skb);
+        __le32 ret, old = sh->checksum;
+       const struct skb_checksum_ops ops = {
+               .update  = sctp_csum_update,
+               .combine = sctp_csum_combine,
+       };
+
+       sh->checksum = 0;
+       ret = cpu_to_le32(~__skb_checksum(skb, offset, skb->len - offset,
+                                         ~(__u32)0, &ops));
+       sh->checksum = old;
+
+       return ret;
+}
+
+#endif /* __sctp_checksum_h__ */