[NET]: X86_64 checksum annotations and cleanups.

* sanitize prototypes, annotate
* usual ntohs->shift

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

3 files changed, 53 insertions, 45 deletions

diff --git a/arch/x86_64/lib/csum-partial.c b/arch/x86_64/lib/csum-partial.c
index c493735218d..06ae630de82 100644
--- a/arch/x86_64/lib/csum-partial.c
+++ b/arch/x86_64/lib/csum-partial.c
@@ -132,9 +132,10 @@ static __force_inline unsigned do_csum(const unsigned char *buff, unsigned len)
  *
  * it's best to have buff aligned on a 64-bit boundary
  */
-unsigned csum_partial(const unsigned char *buff, unsigned len, unsigned sum)
+__wsum csum_partial(const void *buff, int len, __wsum sum)
 {
-	return add32_with_carry(do_csum(buff, len), sum); 
+	return (__force __wsum)add32_with_carry(do_csum(buff, len),
+						(__force u32)sum);
 }
 
 EXPORT_SYMBOL(csum_partial);
@@ -143,7 +144,7 @@ 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 csum_fold(csum_partial(buff,len,0));
 }
diff --git a/arch/x86_64/lib/csum-wrappers.c b/arch/x86_64/lib/csum-wrappers.c
index b1320ec5842..fd42a4a095f 100644
--- a/arch/x86_64/lib/csum-wrappers.c
+++ b/arch/x86_64/lib/csum-wrappers.c
@@ -18,9 +18,9 @@
  * Returns an 32bit unfolded checksum of the buffer.
  * src and dst are best aligned to 64bits. 
  */ 
-unsigned int 
-csum_partial_copy_from_user(const unsigned char __user *src, unsigned char *dst,
-			    int len, unsigned int isum, int *errp)
+__wsum
+csum_partial_copy_from_user(const void __user *src, void *dst,
+			    int len, __wsum isum, int *errp)
 { 
 	might_sleep();
 	*errp = 0;
@@ -34,17 +34,19 @@ csum_partial_copy_from_user(const unsigned char __user *src, unsigned char *dst,
 		if (unlikely((unsigned long)src & 6)) {			
 			while (((unsigned long)src & 6) && len >= 2) { 
 				__u16 val16;			
-				*errp = __get_user(val16, (__u16 __user *)src); 
+				*errp = __get_user(val16, (const __u16 __user *)src);
 				if (*errp)
 					return isum;
 				*(__u16 *)dst = val16;
-				isum = add32_with_carry(isum, val16); 
+				isum = (__force __wsum)add32_with_carry(
+						(__force unsigned)isum, val16);
 				src += 2; 
 				dst += 2; 
 				len -= 2;
 			}
 		}
-		isum = csum_partial_copy_generic((__force void *)src,dst,len,isum,errp,NULL);
+		isum = csum_partial_copy_generic((__force const void *)src,
+					dst, len, isum, errp, NULL);
 		if (likely(*errp == 0)) 
 			return isum;
 	} 
@@ -66,9 +68,9 @@ EXPORT_SYMBOL(csum_partial_copy_from_user);
  * Returns an 32bit unfolded checksum of the buffer.
  * src and dst are best aligned to 64bits.
  */ 
-unsigned int 
-csum_partial_copy_to_user(unsigned const char *src, unsigned char __user *dst,
-			  int len, unsigned int isum, int *errp)
+__wsum
+csum_partial_copy_to_user(const void *src, void __user *dst,
+			  int len, __wsum isum, int *errp)
 { 
 	might_sleep();
 	if (unlikely(!access_ok(VERIFY_WRITE, dst, len))) {
@@ -79,7 +81,8 @@ csum_partial_copy_to_user(unsigned const char *src, unsigned char __user *dst,
 	if (unlikely((unsigned long)dst & 6)) {
 		while (((unsigned long)dst & 6) && len >= 2) { 
 			__u16 val16 = *(__u16 *)src;
-			isum = add32_with_carry(isum, val16);
+			isum = (__force __wsum)add32_with_carry(
+					(__force unsigned)isum, val16);
 			*errp = __put_user(val16, (__u16 __user *)dst);
 			if (*errp)
 				return isum;
@@ -104,19 +107,21 @@ EXPORT_SYMBOL(csum_partial_copy_to_user);
  * 
  * Returns an 32bit unfolded checksum of the buffer.
  */ 
-unsigned int 
-csum_partial_copy_nocheck(const unsigned char *src, unsigned char *dst, int len, unsigned int sum)
+__wsum
+csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
 { 
 	return csum_partial_copy_generic(src,dst,len,sum,NULL,NULL);
 } 
 EXPORT_SYMBOL(csum_partial_copy_nocheck);
 
-unsigned short csum_ipv6_magic(struct in6_addr *saddr, struct in6_addr *daddr,
-			       __u32 len, unsigned short proto, unsigned int sum) 
+__sum16 csum_ipv6_magic(const struct in6_addr *saddr,
+			const struct in6_addr *daddr,
+			__u32 len, unsigned short proto, __wsum sum)
 {
 	__u64 rest, sum64;
      
-	rest = (__u64)htonl(len) + (__u64)htons(proto) + (__u64)sum;
+	rest = (__force __u64)htonl(len) + (__force __u64)htons(proto) +
+		(__force __u64)sum;
 	asm("  addq (%[saddr]),%[sum]\n"
 	    "  adcq 8(%[saddr]),%[sum]\n"
 	    "  adcq (%[daddr]),%[sum]\n" 
@@ -124,7 +129,7 @@ unsigned short csum_ipv6_magic(struct in6_addr *saddr, struct in6_addr *daddr,
 	    "  adcq $0,%[sum]\n"
 	    : [sum] "=r" (sum64) 
 	    : "[sum]" (rest),[saddr] "r" (saddr), [daddr] "r" (daddr));
-	return csum_fold(add32_with_carry(sum64 & 0xffffffff, sum64>>32));
+	return csum_fold((__force __wsum)add32_with_carry(sum64 & 0xffffffff, sum64>>32));
 }
 
 EXPORT_SYMBOL(csum_ipv6_magic);
diff --git a/include/asm-x86_64/checksum.h b/include/asm-x86_64/checksum.h
index 989469e8e0b..419fe88a034 100644
--- a/include/asm-x86_64/checksum.h
+++ b/include/asm-x86_64/checksum.h
@@ -19,15 +19,16 @@
  * the last step before putting a checksum into a packet.
  * Make sure not to mix with 64bit checksums.
  */
-static inline unsigned int csum_fold(unsigned int sum)
+static inline __sum16 csum_fold(__wsum sum)
 {
 	__asm__(
 		"  addl %1,%0\n"
 		"  adcl $0xffff,%0"
 		: "=r" (sum)
-		: "r" (sum << 16), "0" (sum & 0xffff0000)
+		: "r" ((__force u32)sum << 16),
+		  "0" ((__force u32)sum & 0xffff0000)
 	);
-	return (~sum) >> 16;
+	return (__force __sum16)(~(__force u32)sum >> 16);
 }
 
 /*
@@ -43,7 +44,7 @@ static inline unsigned int csum_fold(unsigned int sum)
  * iph: ipv4 header
  * ihl: length of header / 4
  */ 
-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)
 {
 	unsigned int sum;
 
@@ -70,7 +71,7 @@ static inline unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl)
 	: "=r" (sum), "=r" (iph), "=r" (ihl)
 	: "1" (iph), "2" (ihl)
 	: "memory");
-	return(sum);
+	return (__force __sum16)sum;
 }
 
 /** 
@@ -84,16 +85,17 @@ static inline unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl)
  * Returns the pseudo header checksum the input data. Result is 
  * 32bit unfolded.
  */
-static inline unsigned long 
-csum_tcpudp_nofold(unsigned saddr, unsigned 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)
 {
 	asm("  addl %1, %0\n"
 	    "  adcl %2, %0\n"
 	    "  adcl %3, %0\n"
 	    "  adcl $0, %0\n"
 		: "=r" (sum)
-	    : "g" (daddr), "g" (saddr), "g" ((ntohs(len)<<16)+proto*256), "0" (sum));
+	    : "g" (daddr), "g" (saddr),
+	      "g" ((len + proto)<<8), "0" (sum));
     return sum;
 }
 
@@ -109,9 +111,9 @@ csum_tcpudp_nofold(unsigned saddr, unsigned daddr, unsigned short len,
  * Returns the 16bit pseudo header checksum the input data already
  * complemented and ready to be filled in.
  */
-static inline unsigned short int 
-csum_tcpudp_magic(unsigned long saddr, unsigned long daddr,
-		  unsigned short len, unsigned short proto, unsigned int sum) 
+static inline __sum16
+csum_tcpudp_magic(__be32 saddr, __be32 daddr,
+		  unsigned short len, unsigned short proto, __wsum sum)
 {
 	return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
 }
@@ -126,25 +128,25 @@ csum_tcpudp_magic(unsigned long saddr, unsigned long daddr,
  * Before filling it in it needs to be csum_fold()'ed.
  * buff should be aligned to a 64bit boundary if possible.
  */ 
-extern unsigned int csum_partial(const unsigned char *buff, unsigned len, unsigned int sum);
+extern __wsum csum_partial(const void *buff, int len, __wsum sum);
 
 #define  _HAVE_ARCH_COPY_AND_CSUM_FROM_USER 1
 #define HAVE_CSUM_COPY_USER 1
 
 
 /* Do not call this directly. Use the wrappers below */
-extern unsigned long csum_partial_copy_generic(const unsigned char *src, const unsigned char *dst,
-					       unsigned len,
-					       unsigned sum, 
+extern __wsum csum_partial_copy_generic(const void *src, const void *dst,
+					       int len,
+					       __wsum sum,
 					       int *src_err_ptr, int *dst_err_ptr);
 
 
-extern unsigned int csum_partial_copy_from_user(const unsigned char __user *src, unsigned char *dst,
-				       int len, unsigned int isum, int *errp);
-extern unsigned int csum_partial_copy_to_user(const unsigned char *src, unsigned char __user *dst,
-				      int len, unsigned int isum, int *errp);
-extern unsigned int csum_partial_copy_nocheck(const unsigned char *src, unsigned char *dst, int len,
-					      unsigned int sum);
+extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst,
+				       int len, __wsum isum, int *errp);
+extern __wsum csum_partial_copy_to_user(const void *src, void __user *dst,
+				      int len, __wsum isum, int *errp);
+extern __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len,
+					      __wsum sum);
 
 /* Old names. To be removed. */
 #define csum_and_copy_to_user csum_partial_copy_to_user
@@ -158,7 +160,7 @@ extern unsigned int csum_partial_copy_nocheck(const unsigned char *src, unsigned
  * Returns the 16bit folded/inverted checksum of the passed buffer.
  * Ready to fill in.
  */
-extern unsigned short ip_compute_csum(unsigned char * buff, int len);
+extern __sum16 ip_compute_csum(const void *buff, int len);
 
 /**
  * csum_ipv6_magic - Compute checksum of an IPv6 pseudo header.
@@ -176,9 +178,9 @@ extern unsigned short ip_compute_csum(unsigned char * buff, int len);
 struct in6_addr;
 
 #define _HAVE_ARCH_IPV6_CSUM 1
-extern unsigned short 
-csum_ipv6_magic(struct in6_addr *saddr, struct in6_addr *daddr,
-		__u32 len, unsigned short proto, unsigned int sum);
+extern __sum16
+csum_ipv6_magic(const struct in6_addr *saddr, const struct in6_addr *daddr,
+		__u32 len, unsigned short proto, __wsum sum);
 
 static inline unsigned add32_with_carry(unsigned a, unsigned b)
 {