patch-2.1.44 linux/include/asm-mips/checksum.h

• Lines: 245
• Date: Mon Jul 7 08:18:55 1997
• Orig file: v2.1.43/linux/include/asm-mips/checksum.h
• Orig date: Sun Nov 3 01:04:41 1996

diff -u --recursive --new-file v2.1.43/linux/include/asm-mips/checksum.h linux/include/asm-mips/checksum.h
@@ -31,15 +31,44 @@
  * here even more important to align src and dst on a 32-bit (or even
  * better 64-bit) boundary
  */
-unsigned int csum_partial_copy(const char *src, char *dst, int len, int sum);
+unsigned int csum_partial_copy(const char *src, char *dst, int len, unsigned int sum);
 
 /*
- * the same as csum_partial, but copies from user space (but on the alpha
+ * the same as csum_partial, but copies from user space (but on MIPS
  * we have just one address space, so this is identical to the above)
+ *
+ * this is obsolete and will go away.
  */
 #define csum_partial_copy_fromuser csum_partial_copy
   
 /*
+ * this is a new version of the above that records errors it finds in *errp,
+ * but continues and zeros the rest of the buffer.
+ */
+unsigned int csum_partial_copy_from_user(const char *src, char *dst, int len, unsigned int sum, int *errp);
+
+/*
+ *	Fold a partial checksum without adding pseudo headers
+ */
+static inline unsigned short int csum_fold(unsigned int sum)
+{
+	__asm__("
+	.set	noat            
+	sll	$1,%0,16
+	addu	%0,$1
+	sltu	$1,%0,$1
+	srl	%0,%0,16
+	addu	%0,$1
+	xori	%0,0xffff
+	.set	at"
+	: "=r" (sum)
+	: "0" (sum)
+	: "$1");
+
+ 	return sum;
+}
+ 
+/*
  *	This is a version of ip_compute_csum() optimized for IP headers,
  *	which always checksum on 4 octet boundaries.
  *
@@ -49,54 +78,48 @@
 static inline unsigned short ip_fast_csum(unsigned char * iph,
 					  unsigned int ihl)
 {
-	unsigned short int sum;
-	unsigned long	dummy1, dummy2;
+	unsigned int sum;
+	unsigned long dummy;
 
 	/*
-	 * This is optimized for 32-bit MIPS processors.
-	 * I tried it in plain C but the generated code looks to bad to
-	 * use with old first generation MIPS CPUs.
-	 * Using 64-bit code could even further improve these routines.
+	 * This is for 32-bit MIPS processors.
 	 */
-	__asm__("
+	__asm__ __volatile__("
 	.set	noreorder
 	.set	noat
-	lw	%0,(%3)
-	subu	%1,4
-	blez	%1,2f
-	sll	%1,%4,2			# delay slot
-	lw	%2,4(%3)
-	addu	%1,%3			# delay slot
-	addu	%0,%2
-	sltu	$1,%0,%2
-	lw	%2,8(%3)
+	lw	%0,(%1)
+	subu	%2,4
+	#blez	%2,2f
+	sll	%2,2			# delay slot
+
+	lw	%3,4(%1)
+	addu	%2,%1			# delay slot
+	addu	%0,%3
+	sltu	$1,%0,%3
+	lw	%3,8(%1)
 	addu	%0,$1
-	addu	%0,%2
-	sltu	$1,%0,%2
-	lw	%2,12(%3)
+	addu	%0,%3
+	sltu	$1,%0,%3
+	lw	%3,12(%1)
 	addu	%0,$1
-	addu	%0,%2
-	sltu	$1,%0,%2
+	addu	%0,%3
+	sltu	$1,%0,%3
 	addu	%0,$1
-1:	lw	%2,16(%3)
-	addu	%1,4
-	addu	%0,%2
-	sltu	$1,%0,%2
-	bne	%1,%3,1b
+
+1:	lw	%3,16(%1)
+	addiu	%1,4
+	addu	%0,%3
+	sltu	$1,%0,%3
+	bne	%2,%1,1b
 	addu	%0,$1			# delay slot
-	srl	$1,%0,16
-	addu	%0,$1
-	sltu	$1,%0,$1
-	addu	%0,$1
-	nor	%0,$0,%0
-	andi	%0,0xffff
+
 2:	.set	at
 	.set	reorder"
-	: "=r" (sum), "=r" (dummy1), "=r" (dummy2)
-	: "r" (iph), "r"(ihl)
+	: "=&r" (sum), "=&r" (iph), "=&r" (ihl), "=&r" (dummy)
+	: "1" (iph), "2" (ihl)
 	: "$1");
 
-	return sum;
+	return csum_fold(sum);
 }
 
 /*
@@ -114,66 +137,38 @@
 	addu	%0,%2
 	sltu	$1,%0,%2
 	addu	%0,$1
+
 	addu	%0,%3
 	sltu	$1,%0,%3
 	addu	%0,$1
+
 	addu	%0,%4
 	sltu	$1,%0,%4
 	addu	%0,$1
-	srl	$1,%0,16
-	addu	%0,$1
-	sltu	$1,%0,$1
-	addu	%0,$1
-	nor	%0,$0,%0
-	andi	%0,0xffff
 	.set	at"
 	: "=r" (sum)
-	: "0" (daddr), "r"(saddr), "r"((ntohs(len)<<16)+proto*256), "r"(sum)
+	: "0" (daddr), "r"(saddr),
+#ifdef __MIPSEL__
+	    "r" ((ntohs(len)<<16)+proto*256),
+#else
+	    "r" (((proto)<<16)+len),
+#endif
+	    "r"(sum)
 	: "$1");
 
-	return (unsigned short)sum;
+	return csum_fold(sum);
 }
 
 /*
- *	Fold a partial checksum without adding pseudo headers
- */
-static inline unsigned short int csum_fold(unsigned int sum)
-{
-    __asm__("
-	.set	noat
-	srl	$1,%0,16
-	addu	%0,$1
-	sltu	$1,%0,$1
-	nor	%0,$0,%0
-	andi	%0,0xffff
-	.set	at"
-	: "=r"(sum)
-	: "0" (sum)
-	: "$1");
-
- 	return sum;
-}
- 
-/*
  * this routine is used for miscellaneous IP-like checksums, mainly
  * in icmp.c
  */
-static inline unsigned short ip_compute_csum(unsigned char * buff, int len) {
-    unsigned short int sum;
-
-    __asm__("
-	.set	noat
-	srl	$1,%0,16
-	addu	%0,$1
-	sltu	$1,%0,$1
-	nor	%0,$0,%0
-	andi	%0,0xffff
-	.set	at"
-	: "=r"(sum)
-	: "r" (csum_partial(buff, len, 0))
-	: "$1");
+static inline unsigned short ip_compute_csum(unsigned char * buff, int len)
+{
+	unsigned int sum;
 
-	return sum;
+	sum = csum_partial(buff, len, 0);
+	return csum_fold(sum);
 }
 
 #define _HAVE_ARCH_IPV6_CSUM
@@ -183,9 +178,7 @@
 						     unsigned short proto,
 						     unsigned int sum) 
 {
-	unsigned long scratch;
-
-        __asm__("
+	__asm__("
 		.set	noreorder
 		.set	noat
 		addu	%0,%5		# proto (long in network byte order)
@@ -234,14 +227,13 @@
 		addu	%0,%1
 		sltu	$1,%0,$1
 		.set	noat
-		.set	noreorder
-                "
-                : "=r" (sum),
-		  "=r" (scratch)
-                : "r" (saddr),
+		.set	noreorder"
+		: "=r" (sum),
+		  "=r" (proto)
+		: "r" (saddr),
 		  "r" (daddr),
-                  "0" (htonl((__u32) (len))),
-		  "r" (htonl(proto)),
+		  "0" (htonl((__u32) (len))),
+		  "1" (htonl(proto)),
 		  "r"(sum)
 		: "$1");