1 files changed, 102 insertions, 0 deletions

diff --git a/arch/ia64/lib/checksum.c b/arch/ia64/lib/checksum.c
new file mode 100644
index 000000000000..beb11721d9f5
--- /dev/null
+++ b/arch/ia64/lib/checksum.c
@@ -0,0 +1,102 @@
+/*
+ * Network checksum routines
+ *
+ * Copyright (C) 1999, 2003 Hewlett-Packard Co
+ *      Stephane Eranian <eranian@hpl.hp.com>
+ *
+ * Most of the code coming from arch/alpha/lib/checksum.c
+ *
+ * This file contains network checksum routines that are better done
+ * in an architecture-specific manner due to speed..
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+
+#include <asm/byteorder.h>
+
+static inline unsigned short
+from64to16 (unsigned long x)
+{
+        /* add up 32-bit words for 33 bits */
+        x = (x & 0xffffffff) + (x >> 32);
+        /* add up 16-bit and 17-bit words for 17+c bits */
+        x = (x & 0xffff) + (x >> 16);
+        /* add up 16-bit and 2-bit for 16+c bit */
+        x = (x & 0xffff) + (x >> 16);
+        /* add up carry.. */
+        x = (x & 0xffff) + (x >> 16);
+        return x;
+}
+
+/*
+ * computes the checksum of the TCP/UDP pseudo-header
+ * returns a 16-bit checksum, already complemented.
+ */
+unsigned short int
+csum_tcpudp_magic (unsigned long saddr, unsigned long daddr, unsigned short len,
+                   unsigned short proto, unsigned int sum)
+{
+        return ~from64to16(saddr + daddr + sum + ((unsigned long) ntohs(len) << 16) +
+                           ((unsigned long) proto << 8));
+}
+
+EXPORT_SYMBOL(csum_tcpudp_magic);
+
+unsigned int
+csum_tcpudp_nofold (unsigned long saddr, unsigned long daddr, unsigned short len,
+                    unsigned short proto, unsigned int sum)
+{
+        unsigned long result;
+
+        result = (saddr + daddr + sum +
+                  ((unsigned long) ntohs(len) << 16) +
+                  ((unsigned long) proto << 8));
+
+        /* Fold down to 32-bits so we don't lose in the typedef-less network stack.  */
+        /* 64 to 33 */
+        result = (result & 0xffffffff) + (result >> 32);
+        /* 33 to 32 */
+        result = (result & 0xffffffff) + (result >> 32);
+        return result;
+}
+
+extern unsigned long do_csum (const unsigned char *, long);
+
+/*
+ * computes the checksum of a memory block at buff, length len,
+ * and adds in "sum" (32-bit)
+ *
+ * returns a 32-bit number suitable for feeding into itself
+ * or csum_tcpudp_magic
+ *
+ * this function must be called with even lengths, except
+ * for the last fragment, which may be odd
+ *
+ * it's best to have buff aligned on a 32-bit boundary
+ */
+unsigned int
+csum_partial (const unsigned char * buff, int len, unsigned int sum)
+{
+        unsigned long result = do_csum(buff, len);
+
+        /* add in old sum, and carry.. */
+        result += sum;
+        /* 32+c bits -> 32 bits */
+        result = (result & 0xffffffff) + (result >> 32);
+        return result;
+}
+
+EXPORT_SYMBOL(csum_partial);
+
+/*
+ * this routine is used for miscellaneous IP-like checksums, mainly
+ * in icmp.c
+ */
+unsigned short
+ip_compute_csum (unsigned char * buff, int len)
+{
+        return ~do_csum(buff,len);
+}
+
+EXPORT_SYMBOL(ip_compute_csum);