Commit 7814e4b6 authored by Al Viro's avatar Al Viro Committed by David S. Miller
Browse files

[NET]: PARISC checksum annotations and cleanups. 



* sanitized prototypes, annotated
* kill shift-by-16 in checksum calculation

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 8e3d8433

arch/parisc/lib/checksum.c

+10 −7
Original line number Diff line number Diff line
@@ -101,11 +101,14 @@ static inline unsigned int do_csum(const unsigned char * buff, int len) 
/*

 * computes a partial checksum, e.g. for TCP/UDP fragments

 */

unsigned int csum_partial(const unsigned char *buff, int len, unsigned int sum)

/*

 * why bother folding?

 */

__wsum csum_partial(const void *buff, int len, __wsum sum)

{

	unsigned int result = do_csum(buff, len);

	addc(result, sum);

	return from32to16(result);

	return (__force __wsum)from32to16(result);

}



EXPORT_SYMBOL(csum_partial);
@@ -113,8 +116,8 @@ EXPORT_SYMBOL(csum_partial); 
/*

 * copy while checksumming, otherwise like csum_partial

 */

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)

{

	/*

	 * It's 2:30 am and I don't feel like doing it real ...
@@ -131,9 +134,9 @@ EXPORT_SYMBOL(csum_partial_copy_nocheck); 
 * Copy from userspace and compute checksum.  If we catch an exception

 * then zero the rest of the buffer.

 */

unsigned int csum_partial_copy_from_user(const unsigned char __user *src,

					unsigned char *dst, int len,

					unsigned int sum, int *err_ptr)

__wsum csum_partial_copy_from_user(const void __user *src,

					void *dst, int len,

					__wsum sum, int *err_ptr)

{

	int missing;

include/asm-parisc/checksum.h

+26 −29
Original line number Diff line number Diff line
@@ -15,7 +15,7 @@ 
 *

 * it's best to have buff aligned on a 32-bit boundary

 */

extern unsigned int csum_partial(const unsigned char *, int, unsigned int);

extern __wsum csum_partial(const void *, int, __wsum);



/*

 * The same as csum_partial, but copies from src while it checksums.
@@ -23,15 +23,14 @@ extern unsigned int csum_partial(const unsigned char *, int, unsigned int); 
 * Here even more important to align src and dst on a 32-bit (or even

 * better 64-bit) boundary

 */

extern unsigned int csum_partial_copy_nocheck(const unsigned char *, unsigned char *,

					      int, unsigned int);

extern __wsum csum_partial_copy_nocheck(const void *, void *, int, __wsum);



/*

 * this is a new version of the above that records errors it finds in *errp,

 * but continues and zeros the rest of the buffer.

 */

extern unsigned int csum_partial_copy_from_user(const unsigned char __user *src,

		unsigned char *dst, int len, unsigned int sum, int *errp);

extern __wsum csum_partial_copy_from_user(const void __user *src,

		void *dst, int len, __wsum sum, int *errp);



/*

 *	Optimized for IP headers, which always checksum on 4 octet boundaries.
@@ -39,11 +38,10 @@ extern unsigned int csum_partial_copy_from_user(const unsigned char __user *src, 
 *	Written by Randolph Chung <tausq@debian.org>, and then mucked with by

 *	LaMont Jones <lamont@debian.org>

 */

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;





	__asm__ __volatile__ (

"	ldws,ma		4(%1), %0\n"

"	addib,<=	-4, %2, 2f\n"
@@ -69,27 +67,27 @@ static inline unsigned short ip_fast_csum(unsigned char * iph, 
	: "1" (iph), "2" (ihl)

	: "r19", "r20", "r21" );



	return(sum);

	return (__force __sum16)sum;

}



/*

 *	Fold a partial checksum

 */

static inline unsigned int csum_fold(unsigned int sum)

static inline __sum16 csum_fold(__wsum csum)

{

	u32 sum = (__force u32)csum;

	/* add the swapped two 16-bit halves of sum,

	   a possible carry from adding the two 16-bit halves,

	   will carry from the lower half into the upper half,

	   giving us the correct sum in the upper half. */

	sum += (sum << 16) + (sum >> 16);

	return (~sum) >> 16;

	return (__force __sum16)(~sum >> 16);

}

 

static inline unsigned long 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)

{

	__asm__(

	"	add  %1, %0, %0\n"
@@ -97,7 +95,7 @@ static inline unsigned long csum_tcpudp_nofold(unsigned long saddr, 
	"	addc %3, %0, %0\n"

	"	addc %%r0, %0, %0\n"

		: "=r" (sum)

		: "r" (daddr), "r"(saddr), "r"((proto<<16)+len), "0"(sum));

		: "r" (daddr), "r"(saddr), "r"(proto+len), "0"(sum));

	return sum;

}
@@ -105,11 +103,10 @@ static inline unsigned long csum_tcpudp_nofold(unsigned long saddr, 
 * computes the checksum of the TCP/UDP pseudo-header

 * 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));

}
@@ -118,17 +115,17 @@ static inline unsigned short int csum_tcpudp_magic(unsigned long saddr, 
 * this routine is used for miscellaneous IP-like checksums, mainly

 * in icmp.c

 */

static inline unsigned short ip_compute_csum(unsigned char * buf, int len) {

static inline __sum16 ip_compute_csum(const void *buf, int len)

{

	 return csum_fold (csum_partial(buf, len, 0));

}





#define _HAVE_ARCH_IPV6_CSUM

static __inline__ unsigned short int csum_ipv6_magic(struct in6_addr *saddr,

						     struct in6_addr *daddr,

						     __u16 len,

						     unsigned short proto,

						     unsigned int sum) 

static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,

					  const struct in6_addr *daddr,

					  __u32 len, unsigned short proto,

					  __wsum sum)

{

	__asm__ __volatile__ (
@@ -193,9 +190,9 @@ static __inline__ unsigned short int csum_ipv6_magic(struct in6_addr *saddr, 
 *	Copy and checksum to user

 */

#define HAVE_CSUM_COPY_USER

static __inline__ unsigned int csum_and_copy_to_user (const unsigned char *src,

						      unsigned char __user *dst,

						      int len, int sum, 

static __inline__ __wsum csum_and_copy_to_user(const void *src,

						      void __user *dst,

						      int len, __wsum sum,

						      int *err_ptr)

{

	/* code stolen from include/asm-mips64 */
@@ -203,7 +200,7 @@ static __inline__ unsigned int csum_and_copy_to_user (const unsigned char *src, 
	 

	if (copy_to_user(dst, src, len)) {

		*err_ptr = -EFAULT;

		return -1;

		return (__force __wsum)-1;

	}



	return sum;