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-rw-r--r--arch/x86/lib/csum-wrappers_64.c97
1 files changed, 97 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..145f9a0bd
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+++ b/arch/x86/lib/csum-wrappers_64.c
@@ -0,0 +1,97 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2002, 2003 Andi Kleen, SuSE Labs.
+ *
+ * Wrappers of assembly checksum functions for x86-64.
+ */
+#include <asm/checksum.h>
+#include <linux/export.h>
+#include <linux/uaccess.h>
+#include <asm/smap.h>
+
+/**
+ * csum_and_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_and_copy_from_user(const void __user *src, void *dst, int len)
+{
+ __wsum sum;
+
+ might_sleep();
+ if (!user_access_begin(src, len))
+ return 0;
+ sum = csum_partial_copy_generic((__force const void *)src, dst, len);
+ user_access_end();
+ return sum;
+}
+
+/**
+ * csum_and_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_and_copy_to_user(const void *src, void __user *dst, int len)
+{
+ __wsum sum;
+
+ might_sleep();
+ if (!user_access_begin(dst, len))
+ return 0;
+ sum = csum_partial_copy_generic(src, (void __force *)dst, len);
+ user_access_end();
+ return sum;
+}
+
+/**
+ * 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)
+{
+ return csum_partial_copy_generic(src, dst, len);
+}
+EXPORT_SYMBOL(csum_partial_copy_nocheck);
+
+__sum16 csum_ipv6_magic(const struct in6_addr *saddr,
+ const struct in6_addr *daddr,
+ __u32 len, __u8 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);