patch-2.1.26 linux/arch/alpha/lib/csum_partial_copy.c

• Lines: 326
• Date: Thu Feb 6 12:44:41 1997
• Orig file: v2.1.25/linux/arch/alpha/lib/csum_partial_copy.c
• Orig date: Wed Jul 17 14:39:21 1996

diff -u --recursive --new-file v2.1.25/linux/arch/alpha/lib/csum_partial_copy.c linux/arch/alpha/lib/csum_partial_copy.c
@@ -7,6 +7,11 @@
  * we do for performance..
  */
 
+#include <linux/types.h>
+#include <asm/string.h>
+#include <asm/uaccess.h>
+
+
 #define ldq_u(x,y) \
 __asm__ __volatile__("ldq_u %0,%1":"=r" (x):"m" (*(unsigned long *)(y)))
 
@@ -31,17 +36,52 @@
 #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_copy_aligned(
-	unsigned long *src, unsigned long *dst,
-	long len, unsigned long checksum)
+static inline unsigned long
+csum_partial_cfu_aligned(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 = *src;
+		unsigned long word;
+		err |= __get_user(word, src);
 		checksum += carry;
 		src++;
 		checksum += word;
@@ -54,7 +94,7 @@
 	checksum += carry;
 	if (len) {
 		unsigned long word, tmp;
-		word = *src;
+		err |= __get_user(word, src);
 		tmp = *dst;
 		mskql(word, len, word);
 		checksum += word;
@@ -63,28 +103,31 @@
 		*dst = word | tmp;
 		checksum += carry;
 	}
-	return checksum;	
+	if (err) *errp = err;
+	return checksum;
 }
 
 /*
  * This is even less fun, but this is still reasonably
  * easy.
  */
-static inline unsigned long csum_partial_copy_dest_aligned(
-	unsigned long *src, unsigned long *dst,
-	unsigned long soff,
-	long len, unsigned long checksum)
+static inline unsigned long
+csum_partial_cfu_dest_aligned(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;
 
-	ldq_u(first,src);
+	err |= __get_user_u(first,src);
 	carry = 0;
 	while (len >= 0) {
 		unsigned long second;
 
-		ldq_u(second, src+1);
+		err |= __get_user_u(second, src+1);
 		extql(first, soff, word);
 		len -= 8;
 		src++;
@@ -102,7 +145,7 @@
 	if (len) {
 		unsigned long tmp;
 		unsigned long second;
-		ldq_u(second, lastsrc);
+		err |= __get_user_u(second, lastsrc);
 		tmp = *dst;
 		extql(first, soff, word);
 		extqh(second, soff, first);
@@ -114,25 +157,28 @@
 		*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_copy_src_aligned(
-	unsigned long *src, unsigned long *dst,
-	unsigned long doff,
-	long len, unsigned long checksum,
-	unsigned long partial_dest)
+static inline unsigned long
+csum_partial_cfu_src_aligned(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;
-		word = *src;
+		err |= __get_user(word, src);
 		len -= 8;
 		insql(word, doff, second_dest);
 		checksum += carry;
@@ -147,7 +193,7 @@
 	checksum += carry;
 	if (len >= 0) {
 		unsigned long second_dest;
-		word = *src;
+		err |= __get_user(word, src);
 		mskql(word, len-doff, word);
 		checksum += word;
 		insql(word, doff, second_dest);
@@ -162,7 +208,7 @@
 		checksum += carry;
 	} else if (len & 7) {
 		unsigned long second_dest;
-		word = *src;
+		err |= __get_user(word, src);
 		ldq_u(second_dest, dst);
 		mskql(word, len-doff, word);
 		checksum += word;
@@ -172,6 +218,7 @@
 		stq_u(partial_dest | word | second_dest, dst);
 		checksum += carry;
 	}
+	if (err) *errp = err;
 	return checksum;
 }
 
@@ -179,24 +226,26 @@
  * 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_copy_unaligned(
-	unsigned long * src, unsigned long * dst,
-	unsigned long soff, unsigned long doff,
-	long len, unsigned long checksum,
-	unsigned long partial_dest)
+static inline unsigned long
+csum_partial_cfu_unaligned(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;
 
-	ldq_u(first, src);
+	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;
 
-		ldq_u(second, src+1);
+		err |= __get_user_u(second, src+1);
 		extql(first, soff, word);
 		checksum += carry;
 		len -= 8;
@@ -216,8 +265,8 @@
 	if (len >= 0) {
 		unsigned long second, word;
 		unsigned long second_dest;
-		
-		ldq_u(second, lastsrc);
+
+		err |= __get_user_u(second, lastsrc);
 		extql(first, soff, word);
 		extqh(second, soff, first);
 		word |= first;
@@ -233,12 +282,12 @@
 			mskqh(second_dest, len, second_dest);
 			stq_u(partial_dest | second_dest, dst+1);
 		}
-		checksum += carry;			
+		checksum += carry;
 	} else if (len & 7) {
 		unsigned long second, word;
 		unsigned long second_dest;
 
-		ldq_u(second, lastsrc);
+		err |= __get_user_u(second, lastsrc);
 		extql(first, soff, word);
 		extqh(second, soff, first);
 		word |= first;
@@ -251,42 +300,51 @@
 		stq_u(partial_dest | word | second_dest, dst);
 		checksum += carry;
 	}
+	if (err) *errp = err;
 	return checksum;
 }
 
-unsigned int csum_partial_copy(char *src, char *dst, int len, int sum)
+unsigned int
+csum_partial_copy_from_user(int *errp, char *src, char *dst,
+			    int len, unsigned int sum)
 {
 	unsigned long checksum = (unsigned) sum;
 	unsigned long soff = 7 & (unsigned long) src;
 	unsigned long doff = 7 & (unsigned long) dst;
 
+	if (!access_ok(src, len, VERIFY_READ)) {
+		*errp = -EFAULT;
+		memset(dst, 0, len);
+		return checksum;
+	}
+
 	if (len) {
 		if (!doff) {
 			if (!soff)
-				checksum = csum_partial_copy_aligned(
+				checksum = csum_partial_cfu_aligned(
 					(unsigned long *) src,
 					(unsigned long *) dst,
-					len-8, checksum);
+					len-8, checksum, errp);
 			else
-				checksum = csum_partial_copy_dest_aligned(
+				checksum = csum_partial_cfu_dest_aligned(
 					(unsigned long *) src,
 					(unsigned long *) dst,
-					soff, len-8, checksum);
+					soff, len-8, checksum, errp);
 		} else {
 			unsigned long partial_dest;
 			ldq_u(partial_dest, dst);
 			if (!soff)
-				checksum = csum_partial_copy_src_aligned(
+				checksum = csum_partial_cfu_src_aligned(
 					(unsigned long *) src,
 					(unsigned long *) dst,
 					doff, len-8, checksum,
-					partial_dest);
+					partial_dest, errp);
 			else
-				checksum = csum_partial_copy_unaligned(
+				checksum = csum_partial_cfu_unaligned(
 					(unsigned long *) src,
 					(unsigned long *) dst,
 					soff, doff, len-8, checksum,
-					partial_dest);
+					partial_dest, errp);
 		}
 		/* 64 -> 33 bits */
 		checksum = (checksum & 0xffffffff) + (checksum >> 32);
@@ -297,4 +355,17 @@
 		checksum = (checksum & 0xffff) + (checksum >> 16);
 	}
 	return checksum;
+}
+
+unsigned int
+csum_partial_copy (const char *src, char *dst, int len, unsigned int sum)
+{
+	unsigned int ret;
+	int error = 0;
+
+	ret = csum_partial_copy_from_user(&error, src, dst, len, sum);
+	if (error)
+		printk("csum_partial_copy_old(): tell mingo to convert me!\n");
+
+	return ret;
 }