1 files changed, 157 insertions, 0 deletions
diff --git a/arch/x86/lib/csum-wrappers_64.c b/arch/x86/lib/csum-wrappers_64.c
new file mode 100644
index 000000000..1318f75d5
--- /dev/null
+++ b/arch/x86/lib/csum-wrappers_64.c
@@ -0,0 +1,157 @@
+/*
+ * Copyright 2002, 2003 Andi Kleen, SuSE Labs.
+ * Subject to the GNU Public License v.2
+ *
+ * Wrappers of assembly checksum functions for x86-64.
+ */
+#include <asm/checksum.h>
+#include <linux/module.h>
+#include <asm/smap.h>
+
+/**
+ * csum_partial_copy_from_user - Copy and checksum from user space.
+ * @src: source address (user space)
+ * @dst: destination address
+ * @len: number of bytes to be copied.
+ * @isum: initial sum that is added into the result (32bit unfolded)
+ * @errp: set to -EFAULT for an bad source address.
+ *
+ * Returns an 32bit unfolded checksum of the buffer.
+ * src and dst are best aligned to 64bits.
+ */
+__wsum
+csum_partial_copy_from_user(const void __user *src, void *dst,
+			    int len, __wsum isum, int *errp)
+{
+	might_sleep();
+	*errp = 0;
+
+	if (!likely(access_ok(VERIFY_READ, src, len)))
+		goto out_err;
+
+	/*
+	 * Why 6, not 7? To handle odd addresses aligned we
+	 * would need to do considerable complications to fix the
+	 * checksum which is defined as an 16bit accumulator. The
+	 * fix alignment code is primarily for performance
+	 * compatibility with 32bit and that will handle odd
+	 * addresses slowly too.
+	 */
+	if (unlikely((unsigned long)src & 6)) {
+		while (((unsigned long)src & 6) && len >= 2) {
+			__u16 val16;
+
+			if (__get_user(val16, (const __u16 __user *)src))
+				goto out_err;
+
+			*(__u16 *)dst = val16;
+			isum = (__force __wsum)add32_with_carry(
+					(__force unsigned)isum, val16);
+			src += 2;
+			dst += 2;
+			len -= 2;
+		}
+	}
+	stac();
+	isum = csum_partial_copy_generic((__force const void *)src,
+				dst, len, isum, errp, NULL);
+	clac();
+	if (unlikely(*errp))
+		goto out_err;
+
+	return isum;
+
+out_err:
+	*errp = -EFAULT;
+	memset(dst, 0, len);
+
+	return isum;
+}
+EXPORT_SYMBOL(csum_partial_copy_from_user);
+
+/**
+ * csum_partial_copy_to_user - Copy and checksum to user space.
+ * @src: source address
+ * @dst: destination address (user space)
+ * @len: number of bytes to be copied.
+ * @isum: initial sum that is added into the result (32bit unfolded)
+ * @errp: set to -EFAULT for an bad destination address.
+ *
+ * Returns an 32bit unfolded checksum of the buffer.
+ * src and dst are best aligned to 64bits.
+ */
+__wsum
+csum_partial_copy_to_user(const void *src, void __user *dst,
+			  int len, __wsum isum, int *errp)
+{
+	__wsum ret;
+
+	might_sleep();
+
+	if (unlikely(!access_ok(VERIFY_WRITE, dst, len))) {
+		*errp = -EFAULT;
+		return 0;
+	}
+
+	if (unlikely((unsigned long)dst & 6)) {
+		while (((unsigned long)dst & 6) && len >= 2) {
+			__u16 val16 = *(__u16 *)src;
+
+			isum = (__force __wsum)add32_with_carry(
+					(__force unsigned)isum, val16);
+			*errp = __put_user(val16, (__u16 __user *)dst);
+			if (*errp)
+				return isum;
+			src += 2;
+			dst += 2;
+			len -= 2;
+		}
+	}
+
+	*errp = 0;
+	stac();
+	ret = csum_partial_copy_generic(src, (void __force *)dst,
+					len, isum, NULL, errp);
+	clac();
+	return ret;
+}
+EXPORT_SYMBOL(csum_partial_copy_to_user);
+
+/**
+ * csum_partial_copy_nocheck - Copy and checksum.
+ * @src: source address
+ * @dst: destination address
+ * @len: number of bytes to be copied.
+ * @sum: initial sum that is added into the result (32bit unfolded)
+ *
+ * Returns an 32bit unfolded checksum of the buffer.
+ */
+__wsum
+csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
+{
+	return csum_partial_copy_generic(src, dst, len, sum, NULL, NULL);
+}
+EXPORT_SYMBOL(csum_partial_copy_nocheck);
+
+__sum16 csum_ipv6_magic(const struct in6_addr *saddr,
+			const struct in6_addr *daddr,
+			__u32 len, unsigned short proto, __wsum sum)
+{
+	__u64 rest, sum64;
+
+	rest = (__force __u64)htonl(len) + (__force __u64)htons(proto) +
+		(__force __u64)sum;
+
+	asm("	addq (%[saddr]),%[sum]\n"
+	    "	adcq 8(%[saddr]),%[sum]\n"
+	    "	adcq (%[daddr]),%[sum]\n"
+	    "	adcq 8(%[daddr]),%[sum]\n"
+	    "	adcq $0,%[sum]\n"
+
+	    : [sum] "=r" (sum64)
+	    : "[sum]" (rest), [saddr] "r" (saddr), [daddr] "r" (daddr));
+
+	return csum_fold(
+	       (__force __wsum)add32_with_carry(sum64 & 0xffffffff, sum64>>32));
+}
+EXPORT_SYMBOL(csum_ipv6_magic);