1 files changed, 253 insertions, 0 deletions
diff --git a/arch/mips/include/asm/checksum.h b/arch/mips/include/asm/checksum.h
new file mode 100644
index 000000000..5f80c28f5
--- /dev/null
+++ b/arch/mips/include/asm/checksum.h
@@ -0,0 +1,253 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1995, 96, 97, 98, 99, 2001 by Ralf Baechle
+ * Copyright (C) 1999 Silicon Graphics, Inc.
+ * Copyright (C) 2001 Thiemo Seufer.
+ * Copyright (C) 2002 Maciej W. Rozycki
+ * Copyright (C) 2014 Imagination Technologies Ltd.
+ */
+#ifndef _ASM_CHECKSUM_H
+#define _ASM_CHECKSUM_H
+
+#ifdef CONFIG_GENERIC_CSUM
+#include <asm-generic/checksum.h>
+#else
+
+#include <linux/in6.h>
+
+#include <linux/uaccess.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
+ */
+__wsum csum_partial(const void *buff, int len, __wsum sum);
+
+__wsum __csum_partial_copy_from_user(const void __user *src, void *dst, int len);
+__wsum __csum_partial_copy_to_user(const void *src, void __user *dst, int len);
+
+#define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
+static inline
+__wsum csum_and_copy_from_user(const void __user *src, void *dst, int len)
+{
+	might_fault();
+	if (!access_ok(src, len))
+		return 0;
+	return __csum_partial_copy_from_user(src, dst, len);
+}
+
+/*
+ * Copy and checksum to user
+ */
+#define HAVE_CSUM_COPY_USER
+static inline
+__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len)
+{
+	might_fault();
+	if (!access_ok(dst, len))
+		return 0;
+	return __csum_partial_copy_to_user(src, dst, len);
+}
+
+/*
+ * the same as csum_partial, but copies from user space (but on MIPS
+ * we have just one address space, so this is identical to the above)
+ */
+#define _HAVE_ARCH_CSUM_AND_COPY
+__wsum __csum_partial_copy_nocheck(const void *src, void *dst, int len);
+static inline __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
+{
+	return __csum_partial_copy_nocheck(src, dst, len);
+}
+
+/*
+ *	Fold a partial checksum without adding pseudo headers
+ */
+static inline __sum16 csum_fold(__wsum csum)
+{
+	u32 sum = (__force u32)csum;
+
+	sum += (sum << 16);
+	csum = (__force __wsum)(sum < (__force u32)csum);
+	sum >>= 16;
+	sum += (__force u32)csum;
+
+	return (__force __sum16)~sum;
+}
+#define csum_fold csum_fold
+
+/*
+ *	This is a version of ip_compute_csum() optimized for IP headers,
+ *	which always checksum on 4 octet boundaries.
+ *
+ *	By Jorge Cwik <jorge@laser.satlink.net>, adapted for linux by
+ *	Arnt Gulbrandsen.
+ */
+static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
+{
+	const unsigned int *word = iph;
+	const unsigned int *stop = word + ihl;
+	unsigned int csum;
+	int carry;
+
+	csum = word[0];
+	csum += word[1];
+	carry = (csum < word[1]);
+	csum += carry;
+
+	csum += word[2];
+	carry = (csum < word[2]);
+	csum += carry;
+
+	csum += word[3];
+	carry = (csum < word[3]);
+	csum += carry;
+
+	word += 4;
+	do {
+		csum += *word;
+		carry = (csum < *word);
+		csum += carry;
+		word++;
+	} while (word != stop);
+
+	return csum_fold(csum);
+}
+#define ip_fast_csum ip_fast_csum
+
+static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
+					__u32 len, __u8 proto,
+					__wsum sum)
+{
+	__asm__(
+	"	.set	push		# csum_tcpudp_nofold\n"
+	"	.set	noat		\n"
+#ifdef CONFIG_32BIT
+	"	addu	%0, %2		\n"
+	"	sltu	$1, %0, %2	\n"
+	"	addu	%0, $1		\n"
+
+	"	addu	%0, %3		\n"
+	"	sltu	$1, %0, %3	\n"
+	"	addu	%0, $1		\n"
+
+	"	addu	%0, %4		\n"
+	"	sltu	$1, %0, %4	\n"
+	"	addu	%0, $1		\n"
+#endif
+#ifdef CONFIG_64BIT
+	"	daddu	%0, %2		\n"
+	"	daddu	%0, %3		\n"
+	"	daddu	%0, %4		\n"
+	"	dsll32	$1, %0, 0	\n"
+	"	daddu	%0, $1		\n"
+	"	sltu	$1, %0, $1	\n"
+	"	dsra32	%0, %0, 0	\n"
+	"	addu	%0, $1		\n"
+#endif
+	"	.set	pop"
+	: "=r" (sum)
+	: "0" ((__force unsigned long)daddr),
+	  "r" ((__force unsigned long)saddr),
+#ifdef __MIPSEL__
+	  "r" ((proto + len) << 8),
+#else
+	  "r" (proto + len),
+#endif
+	  "r" ((__force unsigned long)sum));
+
+	return sum;
+}
+#define csum_tcpudp_nofold csum_tcpudp_nofold
+
+/*
+ * this routine is used for miscellaneous IP-like checksums, mainly
+ * in icmp.c
+ */
+static inline __sum16 ip_compute_csum(const void *buff, int len)
+{
+	return csum_fold(csum_partial(buff, len, 0));
+}
+
+#define _HAVE_ARCH_IPV6_CSUM
+static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
+					  const struct in6_addr *daddr,
+					  __u32 len, __u8 proto,
+					  __wsum sum)
+{
+	__wsum tmp;
+
+	__asm__(
+	"	.set	push		# csum_ipv6_magic\n"
+	"	.set	noreorder	\n"
+	"	.set	noat		\n"
+	"	addu	%0, %5		# proto (long in network byte order)\n"
+	"	sltu	$1, %0, %5	\n"
+	"	addu	%0, $1		\n"
+
+	"	addu	%0, %6		# csum\n"
+	"	sltu	$1, %0, %6	\n"
+	"	lw	%1, 0(%2)	# four words source address\n"
+	"	addu	%0, $1		\n"
+	"	addu	%0, %1		\n"
+	"	sltu	$1, %0, %1	\n"
+
+	"	lw	%1, 4(%2)	\n"
+	"	addu	%0, $1		\n"
+	"	addu	%0, %1		\n"
+	"	sltu	$1, %0, %1	\n"
+
+	"	lw	%1, 8(%2)	\n"
+	"	addu	%0, $1		\n"
+	"	addu	%0, %1		\n"
+	"	sltu	$1, %0, %1	\n"
+
+	"	lw	%1, 12(%2)	\n"
+	"	addu	%0, $1		\n"
+	"	addu	%0, %1		\n"
+	"	sltu	$1, %0, %1	\n"
+
+	"	lw	%1, 0(%3)	\n"
+	"	addu	%0, $1		\n"
+	"	addu	%0, %1		\n"
+	"	sltu	$1, %0, %1	\n"
+
+	"	lw	%1, 4(%3)	\n"
+	"	addu	%0, $1		\n"
+	"	addu	%0, %1		\n"
+	"	sltu	$1, %0, %1	\n"
+
+	"	lw	%1, 8(%3)	\n"
+	"	addu	%0, $1		\n"
+	"	addu	%0, %1		\n"
+	"	sltu	$1, %0, %1	\n"
+
+	"	lw	%1, 12(%3)	\n"
+	"	addu	%0, $1		\n"
+	"	addu	%0, %1		\n"
+	"	sltu	$1, %0, %1	\n"
+
+	"	addu	%0, $1		# Add final carry\n"
+	"	.set	pop"
+	: "=&r" (sum), "=&r" (tmp)
+	: "r" (saddr), "r" (daddr),
+	  "0" (htonl(len)), "r" (htonl(proto)), "r" (sum));
+
+	return csum_fold(sum);
+}
+
+#include <asm-generic/checksum.h>
+#endif /* CONFIG_GENERIC_CSUM */
+
+#endif /* _ASM_CHECKSUM_H */