2002-05-29 Roland McGrath <roland@frob.com>

	* linux-src/arch/alpha/lib/csum_partial_copy.c: New file,
	taken verbatim from Linux 2.2.14.
	* Makefile (arch-lib-srcs): Add csum_partial_copy.c.
	(LINUXSRCS): Match $(arch-lib-srcs) subset in arch/$(asm_syntax)/lib.
	(OBJS): Use delayed evaluation.
	* glue-include/asm/uaccess.h (__get_user): New macro.
	(__m): New macro.

1 files changed, 384 insertions, 0 deletions

diff --git a/pfinet/linux-src/arch/alpha/lib/csum_partial_copy.c b/pfinet/linux-src/arch/alpha/lib/csum_partial_copy.c
new file mode 100644
index 00000000..71308133
--- /dev/null
+++ b/pfinet/linux-src/arch/alpha/lib/csum_partial_copy.c
@@ -0,0 +1,384 @@
+/*
+ * csum_partial_copy - do IP checksumming and copy
+ *
+ * (C) Copyright 1996 Linus Torvalds
+ *
+ * Don't look at this too closely - you'll go mad. The things
+ * we do for performance..
+ */
+
+#include <linux/types.h>
+#include <linux/string.h>
+#include <asm/uaccess.h>
+
+
+#define ldq_u(x,y) \
+__asm__ __volatile__("ldq_u %0,%1":"=r" (x):"m" (*(const unsigned long *)(y)))
+
+#define stq_u(x,y) \
+__asm__ __volatile__("stq_u %1,%0":"=m" (*(unsigned long *)(y)):"r" (x))
+
+#define extql(x,y,z) \
+__asm__ __volatile__("extql %1,%2,%0":"=r" (z):"r" (x),"r" (y))
+
+#define extqh(x,y,z) \
+__asm__ __volatile__("extqh %1,%2,%0":"=r" (z):"r" (x),"r" (y))
+
+#define mskql(x,y,z) \
+__asm__ __volatile__("mskql %1,%2,%0":"=r" (z):"r" (x),"r" (y))
+
+#define mskqh(x,y,z) \
+__asm__ __volatile__("mskqh %1,%2,%0":"=r" (z):"r" (x),"r" (y))
+
+#define insql(x,y,z) \
+__asm__ __volatile__("insql %1,%2,%0":"=r" (z):"r" (x),"r" (y))
+
+#define insqh(x,y,z) \
+__asm__ __volatile__("insqh %1,%2,%0":"=r" (z):"r" (x),"r" (y))
+
+
+#define __get_user_u(x,ptr)				\
+({							\
+	long __guu_err;					\
+	__asm__ __volatile__(				\
+	"1:	ldq_u %0,%2\n"				\
+	"2:\n"						\
+	".section __ex_table,\"a\"\n"			\
+	"	.gprel32 1b\n"				\
+	"	lda %0,2b-1b(%1)\n"			\
+	".previous"					\
+		: "=r"(x), "=r"(__guu_err)		\
+		: "m"(__m(ptr)), "1"(0));		\
+	__guu_err;					\
+})
+
+#define __put_user_u(x,ptr)				\
+({							\
+	long __puu_err;					\
+	__asm__ __volatile__(				\
+	"1:	stq_u %2,%1\n"				\
+	"2:\n"						\
+	".section __ex_table,\"a\"\n"			\
+	"	.gprel32 1b"				\
+	"	lda $31,2b-1b(%0)\n"			\
+	".previous"					\
+		: "=r"(__puu_err)			\
+		: "m"(__m(addr)), "rJ"(x), "0"(0));	\
+	__puu_err;					\
+})
+
+
+/*
+ * Ok. This isn't fun, but this is the EASY case.
+ */
+static inline unsigned long
+csum_partial_cfu_aligned(const unsigned long *src, unsigned long *dst,
+			 long len, unsigned long checksum,
+			 int *errp)
+{
+	unsigned long carry = 0;
+	int err = 0;
+
+	while (len >= 0) {
+		unsigned long word;
+		err |= __get_user(word, src);
+		checksum += carry;
+		src++;
+		checksum += word;
+		len -= 8;
+		carry = checksum < word;
+		*dst = word;
+		dst++;
+	}
+	len += 8;
+	checksum += carry;
+	if (len) {
+		unsigned long word, tmp;
+		err |= __get_user(word, src);
+		tmp = *dst;
+		mskql(word, len, word);
+		checksum += word;
+		mskqh(tmp, len, tmp);
+		carry = checksum < word;
+		*dst = word | tmp;
+		checksum += carry;
+	}
+	if (err) *errp = err;
+	return checksum;
+}
+
+/*
+ * This is even less fun, but this is still reasonably
+ * easy.
+ */
+static inline unsigned long
+csum_partial_cfu_dest_aligned(const unsigned long *src, unsigned long *dst,
+			      unsigned long soff,
+			      long len, unsigned long checksum,
+			      int *errp)
+{
+	unsigned long first;
+	unsigned long word, carry;
+	unsigned long lastsrc = 7+len+(unsigned long)src;
+	int err = 0;
+
+	err |= __get_user_u(first,src);
+	carry = 0;
+	while (len >= 0) {
+		unsigned long second;
+
+		err |= __get_user_u(second, src+1);
+		extql(first, soff, word);
+		len -= 8;
+		src++;
+		extqh(second, soff, first);
+		checksum += carry;
+		word |= first;
+		first = second;
+		checksum += word;
+		*dst = word;
+		dst++;
+		carry = checksum < word;
+	}
+	len += 8;
+	checksum += carry;
+	if (len) {
+		unsigned long tmp;
+		unsigned long second;
+		err |= __get_user_u(second, lastsrc);
+		tmp = *dst;
+		extql(first, soff, word);
+		extqh(second, soff, first);
+		word |= first;
+		mskql(word, len, word);
+		checksum += word;
+		mskqh(tmp, len, tmp);
+		carry = checksum < word;
+		*dst = word | tmp;
+		checksum += carry;
+	}
+	if (err) *errp = err;
+	return checksum;
+}
+
+/*
+ * This is slightly less fun than the above..
+ */
+static inline unsigned long
+csum_partial_cfu_src_aligned(const unsigned long *src, unsigned long *dst,
+			     unsigned long doff,
+			     long len, unsigned long checksum,
+			     unsigned long partial_dest,
+			     int *errp)
+{
+	unsigned long carry = 0;
+	unsigned long word;
+	int err = 0;
+
+	mskql(partial_dest, doff, partial_dest);
+	while (len >= 0) {
+		unsigned long second_dest;
+		err |= __get_user(word, src);
+		len -= 8;
+		insql(word, doff, second_dest);
+		checksum += carry;
+		stq_u(partial_dest | second_dest, dst);
+		src++;
+		checksum += word;
+		insqh(word, doff, partial_dest);
+		carry = checksum < word;
+		dst++;
+	}
+	len += doff;
+	checksum += carry;
+	if (len >= 0) {
+		unsigned long second_dest;
+		err |= __get_user(word, src);
+		mskql(word, len-doff, word);
+		checksum += word;
+		insql(word, doff, second_dest);
+		stq_u(partial_dest | second_dest, dst);
+		carry = checksum < word;
+		if (len) {
+			ldq_u(second_dest, dst+1);
+			insqh(word, doff, partial_dest);
+			mskqh(second_dest, len, second_dest);
+			stq_u(partial_dest | second_dest, dst+1);
+		}
+		checksum += carry;
+	} else if (len & 7) {
+		unsigned long second_dest;
+		err |= __get_user(word, src);
+		ldq_u(second_dest, dst);
+		mskql(word, len-doff, word);
+		checksum += word;
+		mskqh(second_dest, len, second_dest);
+		carry = checksum < word;
+		insql(word, doff, word);
+		stq_u(partial_dest | word | second_dest, dst);
+		checksum += carry;
+	}
+	if (err) *errp = err;
+	return checksum;
+}
+
+/*
+ * This is so totally un-fun that it's frightening. Don't
+ * look at this too closely, you'll go blind.
+ */
+static inline unsigned long
+csum_partial_cfu_unaligned(const unsigned long * src, unsigned long * dst,
+			   unsigned long soff, unsigned long doff,
+			   long len, unsigned long checksum,
+			   unsigned long partial_dest,
+			   int *errp)
+{
+	unsigned long carry = 0;
+	unsigned long first;
+	unsigned long lastsrc;
+	int err = 0;
+
+	err |= __get_user_u(first, src);
+	lastsrc = 7+len+(unsigned long)src;
+	mskql(partial_dest, doff, partial_dest);
+	while (len >= 0) {
+		unsigned long second, word;
+		unsigned long second_dest;
+
+		err |= __get_user_u(second, src+1);
+		extql(first, soff, word);
+		checksum += carry;
+		len -= 8;
+		extqh(second, soff, first);
+		src++;
+		word |= first;
+		first = second;
+		insql(word, doff, second_dest);
+		checksum += word;
+		stq_u(partial_dest | second_dest, dst);
+		carry = checksum < word;
+		insqh(word, doff, partial_dest);
+		dst++;
+	}
+	len += doff;
+	checksum += carry;
+	if (len >= 0) {
+		unsigned long second, word;
+		unsigned long second_dest;
+
+		err |= __get_user_u(second, lastsrc);
+		extql(first, soff, word);
+		extqh(second, soff, first);
+		word |= first;
+		first = second;
+		mskql(word, len-doff, word);
+		checksum += word;
+		insql(word, doff, second_dest);
+		carry = checksum < word;
+		stq_u(partial_dest | second_dest, dst);
+		if (len) {
+			ldq_u(second_dest, dst+1);
+			insqh(word, doff, partial_dest);
+			mskqh(second_dest, len, second_dest);
+			stq_u(partial_dest | second_dest, dst+1);
+		}
+		checksum += carry;
+	} else if (len & 7) {
+		unsigned long second, word;
+		unsigned long second_dest;
+
+		err |= __get_user_u(second, lastsrc);
+		extql(first, soff, word);
+		extqh(second, soff, first);
+		word |= first;
+		ldq_u(second_dest, dst);
+		mskql(word, len-doff, word);
+		checksum += word;
+		mskqh(second_dest, len, second_dest);
+		carry = checksum < word;
+		insql(word, doff, word);
+		stq_u(partial_dest | word | second_dest, dst);
+		checksum += carry;
+	}
+	if (err) *errp = err;
+	return checksum;
+}
+
+static unsigned int
+do_csum_partial_copy_from_user(const char *src, char *dst, int len,
+			       unsigned int sum, int *errp)
+{
+	unsigned long checksum = (unsigned) sum;
+	unsigned long soff = 7 & (unsigned long) src;
+	unsigned long doff = 7 & (unsigned long) dst;
+
+	if (len) {
+		if (!doff) {
+			if (!soff)
+				checksum = csum_partial_cfu_aligned(
+					(const unsigned long *) src,
+					(unsigned long *) dst,
+					len-8, checksum, errp);
+			else
+				checksum = csum_partial_cfu_dest_aligned(
+					(const unsigned long *) src,
+					(unsigned long *) dst,
+					soff, len-8, checksum, errp);
+		} else {
+			unsigned long partial_dest;
+			ldq_u(partial_dest, dst);
+			if (!soff)
+				checksum = csum_partial_cfu_src_aligned(
+					(const unsigned long *) src,
+					(unsigned long *) dst,
+					doff, len-8, checksum,
+					partial_dest, errp);
+			else
+				checksum = csum_partial_cfu_unaligned(
+					(const unsigned long *) src,
+					(unsigned long *) dst,
+					soff, doff, len-8, checksum,
+					partial_dest, errp);
+		}
+		/* 64 -> 33 bits */
+		checksum = (checksum & 0xffffffff) + (checksum >> 32);
+		/* 33 -> < 32 bits */
+		checksum = (checksum & 0xffff) + (checksum >> 16);
+		/* 32 -> 16 bits */
+		checksum = (checksum & 0xffff) + (checksum >> 16);
+		checksum = (checksum & 0xffff) + (checksum >> 16);
+	}
+	return checksum;
+}
+
+unsigned int
+csum_partial_copy_from_user(const char *src, char *dst, int len,
+			    unsigned int sum, int *errp)
+{
+	if (!access_ok(src, len, VERIFY_READ)) {
+		*errp = -EFAULT;
+		memset(dst, 0, len);
+		return sum;
+	}
+
+	return do_csum_partial_copy_from_user(src, dst, len, sum, errp);
+}
+
+unsigned int
+csum_partial_copy_nocheck(const char *src, char *dst, int len, unsigned int sum)
+{
+	return do_csum_partial_copy_from_user(src, dst, len, sum, NULL);
+}
+
+unsigned int
+csum_partial_copy (const char *src, char *dst, int len, unsigned int sum)
+{
+	unsigned int ret;
+	int error = 0;
+
+	ret = do_csum_partial_copy_from_user(src, dst, len, sum, &error);
+	if (error)
+		printk("csum_partial_copy_old(): tell mingo to convert me!\n");
+
+	return ret;
+}