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-rw-r--r--include/asm-m68k/checksum.h150
1 files changed, 150 insertions, 0 deletions
diff --git a/include/asm-m68k/checksum.h b/include/asm-m68k/checksum.h
new file mode 100644
index 00000000000..78860c20db0
--- /dev/null
+++ b/include/asm-m68k/checksum.h
@@ -0,0 +1,150 @@
+#ifndef _M68K_CHECKSUM_H
+#define _M68K_CHECKSUM_H
+
+#include <linux/in6.h>
+
+/*
+ * 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);
+
+/*
+ * the same as csum_partial, but copies from src while it
+ * checksums
+ *
+ * here even more important to align src and dst on a 32-bit (or even
+ * better 64-bit) boundary
+ */
+
+extern unsigned int csum_partial_copy_from_user(const unsigned char *src,
+ unsigned char *dst,
+ int len, int sum,
+ int *csum_err);
+
+extern unsigned int csum_partial_copy_nocheck(const unsigned char *src,
+ unsigned char *dst, int len,
+ int sum);
+
+/*
+ * This is a version of ip_compute_csum() optimized for IP headers,
+ * which always checksum on 4 octet boundaries.
+ *
+ */
+static inline unsigned short
+ip_fast_csum(unsigned char *iph, unsigned int ihl)
+{
+ unsigned int sum = 0;
+ unsigned long tmp;
+
+ __asm__ ("subqw #1,%2\n"
+ "1:\t"
+ "movel %1@+,%3\n\t"
+ "addxl %3,%0\n\t"
+ "dbra %2,1b\n\t"
+ "movel %0,%3\n\t"
+ "swap %3\n\t"
+ "addxw %3,%0\n\t"
+ "clrw %3\n\t"
+ "addxw %3,%0\n\t"
+ : "=d" (sum), "=&a" (iph), "=&d" (ihl), "=&d" (tmp)
+ : "0" (sum), "1" (iph), "2" (ihl)
+ : "memory");
+ return ~sum;
+}
+
+/*
+ * Fold a partial checksum
+ */
+
+static inline unsigned int csum_fold(unsigned int sum)
+{
+ unsigned int tmp = sum;
+ __asm__("swap %1\n\t"
+ "addw %1, %0\n\t"
+ "clrw %1\n\t"
+ "addxw %1, %0"
+ : "=&d" (sum), "=&d" (tmp)
+ : "0" (sum), "1" (tmp));
+ return ~sum;
+}
+
+
+static inline unsigned int
+csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len,
+ unsigned short proto, unsigned int sum)
+{
+ __asm__ ("addl %2,%0\n\t"
+ "addxl %3,%0\n\t"
+ "addxl %4,%0\n\t"
+ "clrl %1\n\t"
+ "addxl %1,%0"
+ : "=&d" (sum), "=d" (saddr)
+ : "g" (daddr), "1" (saddr), "d" (len + proto),
+ "0" (sum));
+ return sum;
+}
+
+
+/*
+ * computes the checksum of the TCP/UDP pseudo-header
+ * returns a 16-bit checksum, already complemented
+ */
+static inline unsigned short int
+csum_tcpudp_magic(unsigned long saddr, unsigned long daddr, unsigned short len,
+ unsigned short proto, unsigned int sum)
+{
+ return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
+}
+
+/*
+ * this routine is used for miscellaneous IP-like checksums, mainly
+ * in icmp.c
+ */
+
+static inline unsigned short
+ip_compute_csum(unsigned char * buff, int len)
+{
+ return csum_fold (csum_partial(buff, len, 0));
+}
+
+#define _HAVE_ARCH_IPV6_CSUM
+static __inline__ unsigned short int
+csum_ipv6_magic(struct in6_addr *saddr, struct in6_addr *daddr,
+ __u32 len, unsigned short proto, unsigned int sum)
+{
+ register unsigned long tmp;
+ __asm__("addl %2@,%0\n\t"
+ "movel %2@(4),%1\n\t"
+ "addxl %1,%0\n\t"
+ "movel %2@(8),%1\n\t"
+ "addxl %1,%0\n\t"
+ "movel %2@(12),%1\n\t"
+ "addxl %1,%0\n\t"
+ "movel %3@,%1\n\t"
+ "addxl %1,%0\n\t"
+ "movel %3@(4),%1\n\t"
+ "addxl %1,%0\n\t"
+ "movel %3@(8),%1\n\t"
+ "addxl %1,%0\n\t"
+ "movel %3@(12),%1\n\t"
+ "addxl %1,%0\n\t"
+ "addxl %4,%0\n\t"
+ "clrl %1\n\t"
+ "addxl %1,%0"
+ : "=&d" (sum), "=&d" (tmp)
+ : "a" (saddr), "a" (daddr), "d" (len + proto),
+ "0" (sum));
+
+ return csum_fold(sum);
+}
+
+#endif /* _M68K_CHECKSUM_H */