csum_partial_copy_nocheck(): drop the last argument

It's always 0.  Note that we theoretically could use ~0U as well -
result will be the same modulo 0xffff, _if_ the damn thing did the
right thing for any value of initial sum; later we'll make use of
that when convenient.

However, unlike csum_and_copy_..._user(), there are instances that
did not work for arbitrary initial sums; c6x is one such.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/alpha/include/asm/checksum.h

@@ -45,7 +45,7 @@ extern __wsum csum_partial(const void *buff, int len, __wsum sum);
 #define _HAVE_ARCH_CSUM_AND_COPY
 __wsum csum_and_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *errp);
 
-__wsum csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
+__wsum csum_partial_copy_nocheck(const void *src, void *dst, int len);
 
 
 /*

arch/alpha/lib/csum_partial_copy.c

@@ -372,13 +372,13 @@ csum_and_copy_from_user(const void __user *src, void *dst, int len,
 EXPORT_SYMBOL(csum_and_copy_from_user);
 
 __wsum
-csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
+csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
 	__wsum checksum;
 	mm_segment_t oldfs = get_fs();
 	set_fs(KERNEL_DS);
 	checksum = csum_and_copy_from_user((__force const void __user *)src,
-						dst, len, sum, NULL);
+						dst, len, 0, NULL);
 	set_fs(oldfs);
 	return checksum;
 }

arch/arm/include/asm/checksum.h

@@ -35,7 +35,7 @@ __wsum csum_partial(const void *buff, int len, __wsum sum);
  */
 
 __wsum
-csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
+csum_partial_copy_nocheck(const void *src, void *dst, int len);
 
 __wsum
 csum_partial_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *err_ptr);

arch/arm/lib/csumpartialcopy.S

@@ -9,13 +9,14 @@
 
 		.text
 
-/* Function: __u32 csum_partial_copy_nocheck(const char *src, char *dst, int len, __u32 sum)
- * Params  : r0 = src, r1 = dst, r2 = len, r3 = checksum
+/* Function: __u32 csum_partial_copy_nocheck(const char *src, char *dst, int len)
+ * Params  : r0 = src, r1 = dst, r2 = len
  * Returns : r0 = new checksum
  */
 
 		.macro	save_regs
 		stmfd	sp!, {r1, r4 - r8, lr}
+		mov	r3, #0
 		.endm
 
 		.macro	load_regs

arch/c6x/include/asm/checksum.h

@@ -27,7 +27,7 @@ csum_tcpudp_nofold(__be32 saddr, __be32 daddr, __u32 len,
 #define csum_tcpudp_nofold csum_tcpudp_nofold
 
 #define _HAVE_ARCH_CSUM_AND_COPY
-extern __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
+extern __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len);
 
 #include <asm-generic/checksum.h>
 

arch/c6x/lib/csum_64plus.S

@@ -24,7 +24,6 @@
 ENTRY(csum_partial_copy_nocheck)
 	MVC	.S2	ILC,B30
 
-	MV	.D1X	B6,A31		; given csum
 	ZERO	.D1	A9		; csum (a side)
 ||	ZERO	.D2	B9		; csum (b side)
 ||	SHRU	.S2X	A6,2,B5		; len / 4
@@ -144,8 +143,7 @@ L91:	SHRU	.S2X	A9,16,B4
 	SHRU	.S1	A9,16,A0
    [A0]	BNOP	.S1	L91,5
 
-L10:	ADD	.D1	A31,A9,A9
-	MV	.D1	A9,A4
+L10:	MV	.D1	A9,A4
 
 	BNOP	.S2	B3,4
 	MVC	.S2	B30,ILC

arch/m68k/include/asm/checksum.h

@@ -38,8 +38,7 @@ extern __wsum csum_and_copy_from_user(const void __user *src,
 						int *csum_err);
 
 extern __wsum csum_partial_copy_nocheck(const void *src,
-					      void *dst, int len,
-					      __wsum sum);
+					      void *dst, int len);
 
 /*
  *	This is a version of ip_fast_csum() optimized for IP headers,

arch/m68k/lib/checksum.c

@@ -324,9 +324,10 @@ EXPORT_SYMBOL(csum_and_copy_from_user);
  */
 
 __wsum
-csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
+csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
 	unsigned long tmp1, tmp2;
+	__wsum sum = 0;
 	__asm__("movel %2,%4\n\t"
 		"btst #1,%4\n\t"	/* Check alignment */
 		"jeq 2f\n\t"

arch/mips/include/asm/checksum.h

@@ -102,8 +102,11 @@ __wsum csum_and_copy_to_user(const void *src, void __user *dst, int len,
  * we have just one address space, so this is identical to the above)
  */
 #define _HAVE_ARCH_CSUM_AND_COPY
-__wsum csum_partial_copy_nocheck(const void *src, void *dst,
-				       int len, __wsum sum);
+__wsum __csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
+static inline __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
+{
+	return __csum_partial_copy_nocheck(src, dst, len, 0);
+}
 
 /*
  *	Fold a partial checksum without adding pseudo headers

arch/mips/lib/csum_partial.S

@@ -462,8 +462,8 @@ EXPORT_SYMBOL(csum_partial)
 	lw	errptr, 16(sp)
 #endif
 	.if \__nocheck == 1
-	FEXPORT(csum_partial_copy_nocheck)
-	EXPORT_SYMBOL(csum_partial_copy_nocheck)
+	FEXPORT(__csum_partial_copy_nocheck)
+	EXPORT_SYMBOL(__csum_partial_copy_nocheck)
 	.endif
 	move	sum, zero
 	move	odd, zero

arch/powerpc/include/asm/checksum.h

@@ -30,8 +30,8 @@ extern __wsum csum_and_copy_to_user(const void *src, void __user *dst,
 				    int len, __wsum sum, int *err_ptr);
 
 #define _HAVE_ARCH_CSUM_AND_COPY
-#define csum_partial_copy_nocheck(src, dst, len, sum)   \
-        csum_partial_copy_generic((src), (dst), (len), (sum), NULL, NULL)
+#define csum_partial_copy_nocheck(src, dst, len)   \
+        csum_partial_copy_generic((src), (dst), (len), 0, NULL, NULL)
 
 
 /*

arch/sh/include/asm/checksum_32.h

@@ -43,10 +43,9 @@ asmlinkage __wsum csum_partial_copy_generic(const void *src, void *dst,
  *	access_ok().
  */
 static inline
-__wsum csum_partial_copy_nocheck(const void *src, void *dst,
-				 int len, __wsum sum)
+__wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
-	return csum_partial_copy_generic(src, dst, len, sum, NULL, NULL);
+	return csum_partial_copy_generic(src, dst, len, 0, NULL, NULL);
 }
 
 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER

arch/sparc/include/asm/checksum_32.h

@@ -42,7 +42,7 @@ __wsum csum_partial(const void *buff, int len, __wsum sum);
 unsigned int __csum_partial_copy_sparc_generic (const unsigned char *, unsigned char *);
 
 static inline __wsum
-csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
+csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
 	register unsigned int ret asm("o0") = (unsigned int)src;
 	register char *d asm("o1") = dst;
@@ -52,7 +52,7 @@ csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
 		"call __csum_partial_copy_sparc_generic\n\t"
 		" mov %6, %%g7\n"
 	: "=&r" (ret), "=&r" (d), "=&r" (l)
-	: "0" (ret), "1" (d), "2" (l), "r" (sum)
+	: "0" (ret), "1" (d), "2" (l), "r" (0)
 	: "o2", "o3", "o4", "o5", "o7",
 	  "g2", "g3", "g4", "g5", "g7",
 	  "memory", "cc");

arch/sparc/include/asm/checksum_64.h

@@ -38,8 +38,12 @@ __wsum csum_partial(const void * buff, int len, __wsum sum);
  * here even more important to align src and dst on a 32-bit (or even
  * better 64-bit) boundary
  */
-__wsum csum_partial_copy_nocheck(const void *src, void *dst,
-				 int len, __wsum sum);
+__wsum __csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
+
+static inline __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
+{
+	return __csum_partial_copy_nocheck(src, dst, len, 0);
+}
 
 long __csum_partial_copy_from_user(const void __user *src,
 				   void *dst, int len,

arch/sparc/lib/csum_copy.S

@@ -33,7 +33,7 @@
 #endif
 
 #ifndef FUNC_NAME
-#define FUNC_NAME	csum_partial_copy_nocheck
+#define FUNC_NAME	__csum_partial_copy_nocheck
 #endif
 
 	.register	%g2, #scratch

arch/x86/include/asm/checksum_32.h

@@ -38,10 +38,9 @@ asmlinkage __wsum csum_partial_copy_generic(const void *src, void *dst,
  *	If you use these functions directly please don't forget the
  *	access_ok().
  */
-static inline __wsum csum_partial_copy_nocheck(const void *src, void *dst,
-					       int len, __wsum sum)
+static inline __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
-	return csum_partial_copy_generic(src, dst, len, sum, NULL, NULL);
+	return csum_partial_copy_generic(src, dst, len, 0, NULL, NULL);
 }
 
 static inline __wsum csum_and_copy_from_user(const void __user *src,

arch/x86/include/asm/checksum_64.h

@@ -139,8 +139,7 @@ extern __wsum csum_and_copy_from_user(const void __user *src, void *dst,
 					  int len, __wsum isum, int *errp);
 extern __wsum csum_and_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);
+extern __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len);
 
 /**
  * ip_compute_csum - Compute an 16bit IP checksum.

arch/x86/lib/csum-wrappers_64.c

@@ -129,9 +129,9 @@ EXPORT_SYMBOL(csum_and_copy_to_user);
  * Returns an 32bit unfolded checksum of the buffer.
  */
 __wsum
-csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
+csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
-	return csum_partial_copy_generic(src, dst, len, sum, NULL, NULL);
+	return csum_partial_copy_generic(src, dst, len, 0, NULL, NULL);
 }
 EXPORT_SYMBOL(csum_partial_copy_nocheck);
 

arch/xtensa/include/asm/checksum.h

@@ -47,10 +47,9 @@ asmlinkage __wsum csum_partial_copy_generic(const void *src, void *dst,
  *	passed in an incorrect kernel address to one of these functions.
  */
 static inline
-__wsum csum_partial_copy_nocheck(const void *src, void *dst,
-					int len, __wsum sum)
+__wsum csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
-	return csum_partial_copy_generic(src, dst, len, sum, NULL, NULL);
+	return csum_partial_copy_generic(src, dst, len, 0, NULL, NULL);
 }
 
 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER

drivers/net/ethernet/3com/typhoon.c

@@ -1419,8 +1419,7 @@ typhoon_download_firmware(struct typhoon *tp)
 			 * the checksum, we can do this once, at the end.
 			 */
 			csum = csum_fold(csum_partial_copy_nocheck(image_data,
-								   dpage, len,
-								   0));
+								   dpage, len));
 
 			iowrite32(len, ioaddr + TYPHOON_REG_BOOT_LENGTH);
 			iowrite32(le16_to_cpu((__force __le16)csum),

include/net/checksum.h

@@ -49,10 +49,10 @@ static __inline__ __wsum csum_and_copy_to_user
 
 #ifndef _HAVE_ARCH_CSUM_AND_COPY
 static inline __wsum
-csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
+csum_partial_copy_nocheck(const void *src, void *dst, int len)
 {
 	memcpy(dst, src, len);
-	return csum_partial(dst, len, sum);
+	return csum_partial(dst, len, 0);
 }
 #endif
 

lib/iov_iter.c

@@ -581,7 +581,7 @@ static size_t copy_pipe_to_iter(const void *addr, size_t bytes,
 static __wsum csum_and_memcpy(void *to, const void *from, size_t len,
 			      __wsum sum, size_t off)
 {
-	__wsum next = csum_partial_copy_nocheck(from, to, len, 0);
+	__wsum next = csum_partial_copy_nocheck(from, to, len);
 	return csum_block_add(sum, next, off);
 }
 

net/core/skbuff.c

@@ -2736,7 +2736,7 @@ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset,
 		if (copy > len)
 			copy = len;
 		csum = csum_partial_copy_nocheck(skb->data + offset, to,
-						 copy, 0);
+						 copy);
 		if ((len -= copy) == 0)
 			return csum;
 		offset += copy;
@@ -2766,7 +2766,7 @@ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset,
 				vaddr = kmap_atomic(p);
 				csum2 = csum_partial_copy_nocheck(vaddr + p_off,
 								  to + copied,
-								  p_len, 0);
+								  p_len);
 				kunmap_atomic(vaddr);
 				csum = csum_block_add(csum, csum2, pos);
 				pos += p_len;

net/ipv4/icmp.c

@@ -381,7 +381,7 @@ static void icmp_push_reply(struct icmp_bxm *icmp_param,
 
 		csum = csum_partial_copy_nocheck((void *)&icmp_param->data,
 						 (char *)icmph,
-						 icmp_param->head_len, 0);
+						 icmp_param->head_len);
 		skb_queue_walk(&sk->sk_write_queue, skb1) {
 			csum = csum_add(csum, skb1->csum);
 		}

net/ipv4/ip_output.c

@@ -1648,7 +1648,7 @@ static int ip_reply_glue_bits(void *dptr, char *to, int offset,
 {
 	__wsum csum;
 
-	csum = csum_partial_copy_nocheck(dptr+offset, to, len, 0);
+	csum = csum_partial_copy_nocheck(dptr+offset, to, len);
 	skb->csum = csum_block_add(skb->csum, csum, odd);
 	return 0;
 }

net/ipv4/raw.c

@@ -478,7 +478,7 @@ static int raw_getfrag(void *from, char *to, int offset, int len, int odd,
 			skb->csum = csum_block_add(
 				skb->csum,
 				csum_partial_copy_nocheck(rfv->hdr.c + offset,
-							  to, copy, 0),
+							  to, copy),
 				odd);
 
 		odd = 0;

net/ipv6/raw.c

@@ -746,7 +746,7 @@ static int raw6_getfrag(void *from, char *to, int offset, int len, int odd,
 			skb->csum = csum_block_add(
 				skb->csum,
 				csum_partial_copy_nocheck(rfv->c + offset,
-							  to, copy, 0),
+							  to, copy),
 				odd);
 
 		odd = 0;