[NET]: Cris checksum annotations and cleanups.

* sanitize prototypes and annotate
* kill cast-as-lvalue abuses in csum_partial()
* usual ntohs-equals-shift for checksum purposes
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/cris/arch-v10/lib/old_checksum.c

@@ -47,39 +47,41 @@
 
 #include <asm/delay.h>
 
-unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum)
+__wsum csum_partial(const void *p, int len, __wsum __sum)
 {
-  /*
-   * Experiments with ethernet and slip connections show that buff
-   * is aligned on either a 2-byte or 4-byte boundary.
-   */
-  const unsigned char *endMarker = buff + len;
-  const unsigned char *marker = endMarker - (len % 16);
+	u32 sum = (__force u32)__sum;
+	const u16 *buff = p;
+	/*
+	* Experiments with ethernet and slip connections show that buff
+	* is aligned on either a 2-byte or 4-byte boundary.
+	*/
+	const void *endMarker = p + len;
+	const void *marker = endMarker - (len % 16);
 #if 0
-  if((int)buff & 0x3)
-    printk("unaligned buff %p\n", buff);
-  __delay(900); /* extra delay of 90 us to test performance hit */
+	if((int)buff & 0x3)
+		printk("unaligned buff %p\n", buff);
+	__delay(900); /* extra delay of 90 us to test performance hit */
 #endif
-  BITON;
-  while (buff < marker) {
-    sum += *((unsigned short *)buff)++;
-    sum += *((unsigned short *)buff)++;
-    sum += *((unsigned short *)buff)++;
-    sum += *((unsigned short *)buff)++;
-    sum += *((unsigned short *)buff)++;
-    sum += *((unsigned short *)buff)++;
-    sum += *((unsigned short *)buff)++;
-    sum += *((unsigned short *)buff)++;
-  }
-  marker = endMarker - (len % 2);
-  while(buff < marker) {
-    sum += *((unsigned short *)buff)++;
-  }
-  if(endMarker - buff > 0) {
-    sum += *buff;                 /* add extra byte seperately */
-  }
-  BITOFF;
-  return(sum);
+	BITON;
+	while (buff < marker) {
+		sum += *buff++;
+		sum += *buff++;
+		sum += *buff++;
+		sum += *buff++;
+		sum += *buff++;
+		sum += *buff++;
+		sum += *buff++;
+		sum += *buff++;
+	}
+	marker = endMarker - (len % 2);
+	while (buff < marker)
+		sum += *buff++;
+
+	if (endMarker > buff)
+		sum += *(const u8 *)buff;	/* add extra byte seperately */
+
+	BITOFF;
+	return (__force __wsum)sum;
 }
 
 EXPORT_SYMBOL(csum_partial);

include/asm-cris/arch-v10/checksum.h

@@ -8,11 +8,11 @@
  * to split all of those into 16-bit components, then add.
  */
 
-static inline unsigned int
-csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len,
-		   unsigned short proto, unsigned int sum)
+static inline __wsum
+csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len,
+		   unsigned short proto, __wsum sum)
 {
-	int res;
+	__wsum res;
 	__asm__ ("add.d %2, %0\n\t"
 		 "ax\n\t"
 		 "add.d %3, %0\n\t"
@@ -21,7 +21,7 @@ csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len,
 		 "ax\n\t"
 		 "addq 0, %0\n"
 	: "=r" (res)
-	: "0" (sum), "r" (daddr), "r" (saddr), "r" ((ntohs(len) << 16) + (proto << 8)));
+	: "0" (sum), "r" (daddr), "r" (saddr), "r" ((len + proto) << 8));
 
 	return res;
 }	

include/asm-cris/arch-v32/checksum.h

@@ -9,11 +9,11 @@
  * checksum. Which means it would be necessary to split all those into
  * 16-bit components and then add.
  */
-static inline unsigned int
-csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr,
-		   unsigned short len, unsigned short proto, unsigned int sum)
+static inline __wsum
+csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
+		   unsigned short len, unsigned short proto, __wsum sum)
 {
-	int res;
+	__wsum res;
 
 	__asm__ __volatile__ ("add.d %2, %0\n\t"
 			      "addc %3, %0\n\t"
@@ -21,7 +21,7 @@ csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr,
 			      "addc 0, %0\n\t"
 			      : "=r" (res)
 			      : "0" (sum), "r" (daddr), "r" (saddr), \
-			      "r" ((ntohs(len) << 16) + (proto << 8)));
+			      "r" ((len + proto) << 8));
 
 	return res;
 }

include/asm-cris/checksum.h

@@ -17,7 +17,7 @@
  *
  * it's best to have buff aligned on a 32-bit boundary
  */
-unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum);
+__wsum csum_partial(const void *buff, int len, __wsum sum);
 
 /*
  * the same as csum_partial, but copies from src while it
@@ -27,26 +27,23 @@ unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum)
  * better 64-bit) boundary
  */
 
-unsigned int csum_partial_copy_nocheck(const char *src, char *dst,
-				       int len, unsigned int sum);
+__wsum csum_partial_copy_nocheck(const void *src, void *dst,
+				       int len, __wsum sum);
 
 /*
  *	Fold a partial checksum into a word
  */
 
-static inline unsigned int csum_fold(unsigned int sum)
+static inline __sum16 csum_fold(__wsum csum)
 {
-	/* the while loop is unnecessary really, it's always enough with two
-	   iterations */
-	
-	while(sum >> 16)
-		sum = (sum & 0xffff) + (sum >> 16); /* add in end-around carry */
-	
-	return ~sum;
+	u32 sum = (__force u32)csum;
+	sum = (sum & 0xffff) + (sum >> 16); /* add in end-around carry */
+	sum = (sum & 0xffff) + (sum >> 16); /* add in end-around carry */
+	return (__force __sum16)~sum;
 }
 
-extern unsigned int csum_partial_copy_from_user(const char *src, char *dst,
-						int len, unsigned int sum, 
+extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst,
+						int len, __wsum sum,
 						int *errptr);
 
 /*
@@ -55,8 +52,7 @@ extern unsigned int csum_partial_copy_from_user(const char *src, char *dst,
  *
  */
 
-static inline unsigned short ip_fast_csum(unsigned char * iph,
-					  unsigned int ihl)
+static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
 {
 	return csum_fold(csum_partial(iph, ihl * 4, 0));
 }
@@ -66,11 +62,10 @@ static inline unsigned short ip_fast_csum(unsigned char * iph,
  * returns a 16-bit checksum, already complemented
  */
 
-static inline unsigned short int csum_tcpudp_magic(unsigned long saddr,
-						   unsigned long daddr,
+static inline __sum16 int csum_tcpudp_magic(__be32 saddr, __be32 daddr,
 						   unsigned short len,
 						   unsigned short proto,
-						   unsigned int sum)
+						   __wsum sum)
 {
 	return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
 }
@@ -80,7 +75,8 @@ static inline unsigned short int csum_tcpudp_magic(unsigned long saddr,
  * in icmp.c
  */
 
-static inline unsigned short ip_compute_csum(unsigned char * buff, int len) {
+static inline __sum16 ip_compute_csum(const void *buff, int len)
+{
 	return csum_fold (csum_partial(buff, len, 0));
 }