[NET]: S390 checksum annotations and cleanups.

* sanitize prototypes, annotate
* kill useless shifts

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/asm-s390/checksum.h

@@ -27,8 +27,8 @@
  *
  * it's best to have buff aligned on a 32-bit boundary
  */
-static inline unsigned int
-csum_partial(const unsigned char * buff, int len, unsigned int sum)
+static inline __wsum
+csum_partial(const void *buff, int len, __wsum sum)
 {
 	register unsigned long reg2 asm("2") = (unsigned long) buff;
 	register unsigned long reg3 asm("3") = (unsigned long) len;
@@ -49,9 +49,9 @@ csum_partial(const unsigned char * buff, int len, unsigned int sum)
  * Copy from userspace and compute checksum.  If we catch an exception
  * then zero the rest of the buffer.
  */
-static inline unsigned int
-csum_partial_copy_from_user(const char __user *src, char *dst,
-                                          int len, unsigned int sum,
+static inline __wsum
+csum_partial_copy_from_user(const void __user *src, void *dst,
+                                          int len, __wsum sum,
                                           int *err_ptr)
 {
 	int missing;
@@ -66,8 +66,8 @@ csum_partial_copy_from_user(const char __user *src, char *dst,
 }
 
 
-static inline unsigned int
-csum_partial_copy_nocheck (const char *src, char *dst, int len, unsigned int sum)
+static inline __wsum
+csum_partial_copy_nocheck (const void *src, void *dst, int len, __wsum sum)
 {
         memcpy(dst,src,len);
 	return csum_partial(dst, len, sum);
@@ -76,8 +76,7 @@ csum_partial_copy_nocheck (const char *src, char *dst, int len, unsigned int sum
 /*
  *      Fold a partial checksum without adding pseudo headers
  */
-static inline unsigned short
-csum_fold(unsigned int sum)
+static inline __sum16 csum_fold(__wsum sum)
 {
 #ifndef __s390x__
 	register_pair rp;
@@ -100,16 +99,15 @@ csum_fold(unsigned int sum)
 		"	srl	%0,16\n"	/* %0 = H+L+C */
 		: "+&d" (sum) : : "cc", "2", "3");
 #endif /* __s390x__ */
-	return ((unsigned short) ~sum);
+	return (__force __sum16) ~sum;
 }
 
 /*
  *	This is a version of ip_compute_csum() optimized for IP headers,
  *	which always checksum on 4 octet boundaries.
  *
  */
-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));
 }
@@ -118,10 +116,10 @@ ip_fast_csum(unsigned char *iph, unsigned int ihl)
  * computes the checksum of the TCP/UDP pseudo-header
  * returns a 32-bit checksum
  */
-static inline unsigned int 
-csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr,
+static inline __wsum
+csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
                    unsigned short len, unsigned short proto,
-                   unsigned int sum)
+                   __wsum sum)
 {
 #ifndef __s390x__
 	asm volatile(
@@ -137,12 +135,12 @@ csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr,
 		"1:"
 		: "+&d" (sum) : "d" (daddr) : "cc");
 	asm volatile(
-		"	alr	%0,%1\n" /* sum += (len<<16) + (proto<<8) */
+		"	alr	%0,%1\n" /* sum += len + proto */
 		"	brc	12,2f\n"
 		"	ahi	%0,1\n"  /* add carry */
 		"2:"
 		: "+&d" (sum)
-		: "d" (((unsigned int) len<<16) + (unsigned int) proto)
+		: "d" (len + proto)
 		: "cc");
 #else /* __s390x__ */
 	asm volatile(
@@ -153,7 +151,7 @@ csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr,
 		"0:	algr	%0,%2\n"  /* sum += daddr */
 		"	brc	12,1f\n"
 		"	aghi	%0,1\n"   /* add carry */
-		"1:	algfr	%0,%3\n"  /* sum += (len<<16) + proto */
+		"1:	algfr	%0,%3\n"  /* sum += len + proto */
 		"	brc	12,2f\n"
 		"	aghi	%0,1\n"   /* add carry */
 		"2:	srlg	0,%0,32\n"
@@ -163,7 +161,7 @@ csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr,
 		"3:	llgfr	%0,%0"
 		: "+&d" (sum)
 		: "d" (saddr), "d" (daddr),
-		  "d" (((unsigned int) len<<16) + (unsigned int) proto)
+		  "d" (len + proto)
 		: "cc", "0");
 #endif /* __s390x__ */
 	return sum;
@@ -174,10 +172,10 @@ csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr,
  * returns a 16-bit checksum, already complemented
  */
 
-static inline unsigned short int
-csum_tcpudp_magic(unsigned long saddr, unsigned long daddr,
+static inline __sum16
+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));
 }
@@ -187,8 +185,7 @@ csum_tcpudp_magic(unsigned long saddr, unsigned long daddr,
  * 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));
 }