1 files changed, 221 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/checksum.h b/arch/powerpc/include/asm/checksum.h
new file mode 100644
index 000000000..4b573a3b7
--- /dev/null
+++ b/arch/powerpc/include/asm/checksum.h
@@ -0,0 +1,221 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _ASM_POWERPC_CHECKSUM_H
+#define _ASM_POWERPC_CHECKSUM_H
+#ifdef __KERNEL__
+
+/*
+ */
+
+#include <linux/bitops.h>
+#include <linux/in6.h>
+/*
+ * Computes the checksum of a memory block at src, length len,
+ * and adds in "sum" (32-bit), while copying the block to dst.
+ * If an access exception occurs on src or dst, it stores -EFAULT
+ * to *src_err or *dst_err respectively (if that pointer is not
+ * NULL), and, for an error on src, zeroes the rest of dst.
+ *
+ * Like csum_partial, this must be called with even lengths,
+ * except for the last fragment.
+ */
+extern __wsum csum_partial_copy_generic(const void *src, void *dst, int len);
+
+#define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
+extern __wsum csum_and_copy_from_user(const void __user *src, void *dst,
+				      int len);
+#define HAVE_CSUM_COPY_USER
+extern __wsum csum_and_copy_to_user(const void *src, void __user *dst,
+				    int len);
+
+#define _HAVE_ARCH_CSUM_AND_COPY
+#define csum_partial_copy_nocheck(src, dst, len)   \
+        csum_partial_copy_generic((src), (dst), (len))
+
+
+/*
+ * turns a 32-bit partial checksum (e.g. from csum_partial) into a
+ * 1's complement 16-bit checksum.
+ */
+static inline __sum16 csum_fold(__wsum sum)
+{
+	u32 tmp = (__force u32)sum;
+
+	/*
+	 * swap the two 16-bit halves of sum
+	 * if there is a carry from adding the two 16-bit halves,
+	 * it will carry from the lower half into the upper half,
+	 * giving us the correct sum in the upper half.
+	 */
+	return (__force __sum16)(~(tmp + rol32(tmp, 16)) >> 16);
+}
+
+static inline u32 from64to32(u64 x)
+{
+	return (x + ror64(x, 32)) >> 32;
+}
+
+static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, __u32 len,
+					__u8 proto, __wsum sum)
+{
+#ifdef __powerpc64__
+	u64 s = (__force u32)sum;
+
+	s += (__force u32)saddr;
+	s += (__force u32)daddr;
+#ifdef __BIG_ENDIAN__
+	s += proto + len;
+#else
+	s += (proto + len) << 8;
+#endif
+	return (__force __wsum) from64to32(s);
+#else
+    __asm__("\n\
+	addc %0,%0,%1 \n\
+	adde %0,%0,%2 \n\
+	adde %0,%0,%3 \n\
+	addze %0,%0 \n\
+	"
+	: "=r" (sum)
+	: "r" (daddr), "r"(saddr), "r"(proto + len), "0"(sum));
+	return sum;
+#endif
+}
+
+/*
+ * computes the checksum of the TCP/UDP pseudo-header
+ * returns a 16-bit checksum, already complemented
+ */
+static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, __u32 len,
+					__u8 proto, __wsum sum)
+{
+	return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum));
+}
+
+#define HAVE_ARCH_CSUM_ADD
+static __always_inline __wsum csum_add(__wsum csum, __wsum addend)
+{
+#ifdef __powerpc64__
+	u64 res = (__force u64)csum;
+
+	res += (__force u64)addend;
+	return (__force __wsum)((u32)res + (res >> 32));
+#else
+	if (__builtin_constant_p(csum) && csum == 0)
+		return addend;
+	if (__builtin_constant_p(addend) && addend == 0)
+		return csum;
+
+	asm("addc %0,%0,%1;"
+	    "addze %0,%0;"
+	    : "+r" (csum) : "r" (addend) : "xer");
+	return csum;
+#endif
+}
+
+#define HAVE_ARCH_CSUM_SHIFT
+static __always_inline __wsum csum_shift(__wsum sum, int offset)
+{
+	/* rotate sum to align it with a 16b boundary */
+	return (__force __wsum)rol32((__force u32)sum, (offset & 1) << 3);
+}
+
+/*
+ * This is a version of ip_compute_csum() optimized for IP headers,
+ * which always checksum on 4 octet boundaries.  ihl is the number
+ * of 32-bit words and is always >= 5.
+ */
+static inline __wsum ip_fast_csum_nofold(const void *iph, unsigned int ihl)
+{
+	const u32 *ptr = (const u32 *)iph + 1;
+#ifdef __powerpc64__
+	unsigned int i;
+	u64 s = *(const u32 *)iph;
+
+	for (i = 0; i < ihl - 1; i++, ptr++)
+		s += *ptr;
+	return (__force __wsum)from64to32(s);
+#else
+	__wsum sum, tmp;
+
+	asm("mtctr %3;"
+	    "addc %0,%4,%5;"
+	    "1: lwzu %1, 4(%2);"
+	    "adde %0,%0,%1;"
+	    "bdnz 1b;"
+	    "addze %0,%0;"
+	    : "=r" (sum), "=r" (tmp), "+b" (ptr)
+	    : "r" (ihl - 2), "r" (*(const u32 *)iph), "r" (*ptr)
+	    : "ctr", "xer", "memory");
+
+	return sum;
+#endif
+}
+
+static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
+{
+	return csum_fold(ip_fast_csum_nofold(iph, ihl));
+}
+
+/*
+ * 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);
+
+static __always_inline __wsum csum_partial(const void *buff, int len, __wsum sum)
+{
+	if (__builtin_constant_p(len) && len <= 16 && (len & 1) == 0) {
+		if (len == 2)
+			sum = csum_add(sum, (__force __wsum)*(const u16 *)buff);
+		if (len >= 4)
+			sum = csum_add(sum, (__force __wsum)*(const u32 *)buff);
+		if (len == 6)
+			sum = csum_add(sum, (__force __wsum)
+					    *(const u16 *)(buff + 4));
+		if (len >= 8)
+			sum = csum_add(sum, (__force __wsum)
+					    *(const u32 *)(buff + 4));
+		if (len == 10)
+			sum = csum_add(sum, (__force __wsum)
+					    *(const u16 *)(buff + 8));
+		if (len >= 12)
+			sum = csum_add(sum, (__force __wsum)
+					    *(const u32 *)(buff + 8));
+		if (len == 14)
+			sum = csum_add(sum, (__force __wsum)
+					    *(const u16 *)(buff + 12));
+		if (len >= 16)
+			sum = csum_add(sum, (__force __wsum)
+					    *(const u32 *)(buff + 12));
+	} else if (__builtin_constant_p(len) && (len & 3) == 0) {
+		sum = csum_add(sum, ip_fast_csum_nofold(buff, len >> 2));
+	} else {
+		sum = __csum_partial(buff, len, sum);
+	}
+	return sum;
+}
+
+/*
+ * 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
+__sum16 csum_ipv6_magic(const struct in6_addr *saddr,
+			const struct in6_addr *daddr,
+			__u32 len, __u8 proto, __wsum sum);
+
+#endif /* __KERNEL__ */
+#endif