[NET]: IA64 checksum annotations and cleanups.

* sanitize prototypes, annotate
* ntohs -> shift in checksum calculations
* kill access_ok() in csum_partial_copy_from_user
* collapse do_csum_partial_copy_from_user
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/ia64/lib/checksum.c

@@ -33,32 +33,32 @@ from64to16 (unsigned long x)
  * computes the checksum of the TCP/UDP pseudo-header
  * returns a 16-bit checksum, already complemented.
  */
-unsigned short int
-csum_tcpudp_magic (unsigned long saddr, unsigned long daddr, unsigned short len,
-		   unsigned short proto, unsigned int sum)
+__sum16
+csum_tcpudp_magic (__be32 saddr, __be32 daddr, unsigned short len,
+		   unsigned short proto, __wsum sum)
 {
-	return ~from64to16(saddr + daddr + sum + ((unsigned long) ntohs(len) << 16) +
-			   ((unsigned long) proto << 8));
+	return (__force __sum16)~from64to16(
+		(__force u64)saddr + (__force u64)daddr +
+		(__force u64)sum + ((len + proto) << 8));
 }
 
 EXPORT_SYMBOL(csum_tcpudp_magic);
 
-unsigned int
-csum_tcpudp_nofold (unsigned long saddr, unsigned long daddr, unsigned short len,
-		    unsigned short proto, unsigned int sum)
+__wsum
+csum_tcpudp_nofold (__be32 saddr, __be32 daddr, unsigned short len,
+		    unsigned short proto, __wsum sum)
 {
 	unsigned long result;
 
-	result = (saddr + daddr + sum +
-		  ((unsigned long) ntohs(len) << 16) +
-		  ((unsigned long) proto << 8));
+	result = (__force u64)saddr + (__force u64)daddr +
+		 (__force u64)sum + ((len + proto) << 8);
 
 	/* Fold down to 32-bits so we don't lose in the typedef-less network stack.  */
 	/* 64 to 33 */
 	result = (result & 0xffffffff) + (result >> 32);
 	/* 33 to 32 */
 	result = (result & 0xffffffff) + (result >> 32);
-	return result;
+	return (__force __wsum)result;
 }
 
 extern unsigned long do_csum (const unsigned char *, long);
@@ -75,16 +75,15 @@ extern unsigned long do_csum (const unsigned char *, long);
  *
  * 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)
 {
-	unsigned long result = do_csum(buff, len);
+	u64 result = do_csum(buff, len);
 
 	/* add in old sum, and carry.. */
-	result += sum;
+	result += (__force u32)sum;
 	/* 32+c bits -> 32 bits */
 	result = (result & 0xffffffff) + (result >> 32);
-	return result;
+	return (__force __wsum)result;
 }
 
 EXPORT_SYMBOL(csum_partial);
@@ -93,10 +92,9 @@ EXPORT_SYMBOL(csum_partial);
  * this routine is used for miscellaneous IP-like checksums, mainly
  * in icmp.c
  */
-unsigned short
-ip_compute_csum (unsigned char * buff, int len)
+__sum16 ip_compute_csum (const void *buff, int len)
 {
-	return ~do_csum(buff,len);
+	return (__force __sum16)~do_csum(buff,len);
 }
 
 EXPORT_SYMBOL(ip_compute_csum);

arch/ia64/lib/csum_partial_copy.c

@@ -104,9 +104,9 @@ unsigned long do_csum_c(const unsigned char * buff, int len, unsigned int psum)
  */
 extern unsigned long do_csum(const unsigned char *, long);
 
-static unsigned int
-do_csum_partial_copy_from_user (const unsigned char __user *src, unsigned char *dst,
-				int len, unsigned int psum, int *errp)
+__wsum
+csum_partial_copy_from_user(const void __user *src, void *dst,
+				int len, __wsum psum, int *errp)
 {
 	unsigned long result;
 
@@ -122,30 +122,17 @@ do_csum_partial_copy_from_user (const unsigned char __user *src, unsigned char *
 	result = do_csum(dst, len);
 
 	/* add in old sum, and carry.. */
-	result += psum;
+	result += (__force u32)psum;
 	/* 32+c bits -> 32 bits */
 	result = (result & 0xffffffff) + (result >> 32);
-	return result;
-}
-
-unsigned int
-csum_partial_copy_from_user (const unsigned char __user *src, unsigned char *dst,
-			     int len, unsigned int sum, int *errp)
-{
-	if (!access_ok(VERIFY_READ, src, len)) {
-		*errp = -EFAULT;
-		memset(dst, 0, len);
-		return sum;
-	}
-
-	return do_csum_partial_copy_from_user(src, dst, len, sum, errp);
+	return (__force __wsum)result;
 }
 
-unsigned int
-csum_partial_copy_nocheck(const unsigned char __user *src, unsigned char *dst,
-			  int len, unsigned int sum)
+__wsum
+csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
 {
-	return do_csum_partial_copy_from_user(src, dst, len, sum, NULL);
+	return csum_partial_copy_from_user((__force const void __user *)src,
+					   dst, len, sum, NULL);
 }
 
 EXPORT_SYMBOL(csum_partial_copy_nocheck);

include/asm-ia64/checksum.h

@@ -10,23 +10,21 @@
  * This is a version of ip_compute_csum() optimized for IP headers,
  * which always checksum on 4 octet boundaries.
  */
-extern unsigned short ip_fast_csum (unsigned char * iph, unsigned int ihl);
+extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
 
 /*
  * Computes the checksum of the TCP/UDP pseudo-header returns a 16-bit
  * checksum, already complemented
  */
-extern unsigned short int csum_tcpudp_magic (unsigned long saddr,
-					     unsigned long daddr,
+extern __sum16 csum_tcpudp_magic (__be32 saddr, __be32 daddr,
 					     unsigned short len,
 					     unsigned short proto,
-					     unsigned int sum);
+					     __wsum sum);
 
-extern unsigned int csum_tcpudp_nofold (unsigned long saddr,
-					unsigned long daddr,
+extern __wsum csum_tcpudp_nofold (__be32 saddr, __be32 daddr,
 					unsigned short len,
 					unsigned short proto,
-					unsigned int sum);
+					__wsum sum);
 
 /*
  * Computes the checksum of a memory block at buff, length len,
@@ -40,8 +38,7 @@ extern unsigned int csum_tcpudp_nofold (unsigned long saddr,
  *
  * it's best to have buff aligned on a 32-bit boundary
  */
-extern unsigned int csum_partial (const unsigned char * buff, int len,
-				  unsigned int sum);
+extern __wsum csum_partial(const void *buff, int len, __wsum sum);
 
 /*
  * Same as csum_partial, but copies from src while it checksums.
@@ -49,28 +46,28 @@ extern unsigned int csum_partial (const unsigned char * buff, int len,
  * Here it is even more important to align src and dst on a 32-bit (or
  * even better 64-bit) boundary.
  */
-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 *errp);
 
-extern unsigned int csum_partial_copy_nocheck (const char *src, char *dst,
-					       int len, unsigned int sum);
+extern __wsum csum_partial_copy_nocheck(const void *src, void *dst,
+					       int len, __wsum sum);
 
 /*
  * This routine is used for miscellaneous IP-like checksums, mainly in
  * icmp.c
  */
-extern unsigned short ip_compute_csum (unsigned char *buff, int len);
+extern __sum16 ip_compute_csum(const void *buff, int len);
 
 /*
  * Fold a partial checksum without adding pseudo headers.
  */
-static inline unsigned short
-csum_fold (unsigned int sum)
+static inline __sum16 csum_fold(__wsum csum)
 {
+	u32 sum = (__force u32)csum;
 	sum = (sum & 0xffff) + (sum >> 16);
 	sum = (sum & 0xffff) + (sum >> 16);
-	return ~sum;
+	return (__force __sum16)~sum;
 }
 
 #endif /* _ASM_IA64_CHECKSUM_H */