1 files changed, 160 insertions, 0 deletions

diff --git a/include/asm-arm/checksum.h b/include/asm-arm/checksum.h
new file mode 100644
index 000000000000..d4256d5f3a7c
--- /dev/null
+++ b/include/asm-arm/checksum.h
@@ -0,0 +1,160 @@
+/*
+ *  linux/include/asm-arm/checksum.h
+ *
+ * IP checksum routines
+ *
+ * Copyright (C) Original authors of ../asm-i386/checksum.h
+ * Copyright (C) 1996-1999 Russell King
+ */
+#ifndef __ASM_ARM_CHECKSUM_H
+#define __ASM_ARM_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, and handles user-space pointer exceptions correctly, when needed.
+ *
+ * here even more important to align src and dst on a 32-bit (or even
+ * better 64-bit) boundary
+ */
+
+unsigned int
+csum_partial_copy_nocheck(const char *src, char *dst, int len, int sum);
+
+unsigned int
+csum_partial_copy_from_user(const char __user *src, char *dst, int len, int sum, int *err_ptr);
+
+/*
+ * This is the old (and unsafe) way of doing checksums, a warning message will
+ * be printed if it is used and an exception occurs.
+ *
+ * this functions should go away after some time.
+ */
+#define csum_partial_copy(src,dst,len,sum)      csum_partial_copy_nocheck(src,dst,len,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, tmp1;
+
+        __asm__ __volatile__(
+        "ldr    %0, [%1], #4            @ ip_fast_csum          \n\
+        ldr     %3, [%1], #4                                    \n\
+        sub     %2, %2, #5                                      \n\
+        adds    %0, %0, %3                                      \n\
+        ldr     %3, [%1], #4                                    \n\
+        adcs    %0, %0, %3                                      \n\
+        ldr     %3, [%1], #4                                    \n\
+1:      adcs    %0, %0, %3                                      \n\
+        ldr     %3, [%1], #4                                    \n\
+        tst     %2, #15                 @ do this carefully     \n\
+        subne   %2, %2, #1              @ without destroying    \n\
+        bne     1b                      @ the carry flag        \n\
+        adcs    %0, %0, %3                                      \n\
+        adc     %0, %0, #0                                      \n\
+        adds    %0, %0, %0, lsl #16                             \n\
+        addcs   %0, %0, #0x10000                                \n\
+        mvn     %0, %0                                          \n\
+        mov     %0, %0, lsr #16"
+        : "=r" (sum), "=r" (iph), "=r" (ihl), "=r" (tmp1)
+        : "1" (iph), "2" (ihl)
+        : "cc");
+        return sum;
+}
+
+/*
+ *      Fold a partial checksum without adding pseudo headers
+ */
+static inline unsigned int
+csum_fold(unsigned int sum)
+{
+        __asm__(
+        "adds   %0, %1, %1, lsl #16     @ csum_fold             \n\
+        addcs   %0, %0, #0x10000"
+        : "=r" (sum)
+        : "r" (sum)
+        : "cc");
+        return (~sum) >> 16;
+}
+
+static inline unsigned int
+csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len,
+                   unsigned int proto, unsigned int sum)
+{
+        __asm__(
+        "adds   %0, %1, %2              @ csum_tcpudp_nofold    \n\
+        adcs    %0, %0, %3                                      \n\
+        adcs    %0, %0, %4                                      \n\
+        adcs    %0, %0, %5                                      \n\
+        adc     %0, %0, #0"
+        : "=&r"(sum)
+        : "r" (sum), "r" (daddr), "r" (saddr), "r" (ntohs(len)), "Ir" (ntohs(proto))
+        : "cc");
+        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 int proto, unsigned int sum)
+{
+        __asm__(
+        "adds   %0, %1, %2              @ csum_tcpudp_magic     \n\
+        adcs    %0, %0, %3                                      \n\
+        adcs    %0, %0, %4                                      \n\
+        adcs    %0, %0, %5                                      \n\
+        adc     %0, %0, #0                                      \n\
+        adds    %0, %0, %0, lsl #16                             \n\
+        addcs   %0, %0, #0x10000                                \n\
+        mvn     %0, %0"
+        : "=&r"(sum)
+        : "r" (sum), "r" (daddr), "r" (saddr), "r" (ntohs(len)), "Ir" (ntohs(proto))
+        : "cc");
+        return sum >> 16;
+}
+
+
+/*
+ * 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
+extern unsigned long
+__csum_ipv6_magic(struct in6_addr *saddr, struct in6_addr *daddr, __u32 len,
+                __u32 proto, unsigned int sum);
+
+static inline unsigned short int
+csum_ipv6_magic(struct in6_addr *saddr, struct in6_addr *daddr, __u32 len,
+                unsigned short proto, unsigned int sum)
+{
+        return csum_fold(__csum_ipv6_magic(saddr, daddr, htonl(len),
+                                           htonl(proto), sum));
+}
+#endif