take the dummy csum_and_copy_from_user() into net/checksum.h

now that can be done conveniently - all non-trivial cases have
_HAVE_ARCH_COPY_AND_CSUM_FROM_USER defined, so the fallback in
net/checksum.h is used only for dummy (copy_from_user, then
csum_partial) implementation.  Allowing us to get rid of all
dummy instances, both of csum_and_copy_from_user() and
csum_partial_copy_from_user().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/c6x/lib/checksum.c

@@ -4,28 +4,6 @@
 #include <linux/module.h>
 #include <net/checksum.h>
 
-#include <asm/byteorder.h>
-
-/*
- * copy from fs while checksumming, otherwise like csum_partial
- */
-__wsum
-csum_partial_copy_from_user(const void __user *src, void *dst, int len,
-			    __wsum sum, int *csum_err)
-{
-	int missing;
-
-	missing = __copy_from_user(dst, src, len);
-	if (missing) {
-		memset(dst + len - missing, 0, missing);
-		*csum_err = -EFAULT;
-	} else
-		*csum_err = 0;
-
-	return csum_partial(dst, len, sum);
-}
-EXPORT_SYMBOL(csum_partial_copy_from_user);
-
 /* These are from csum_64plus.S */
 EXPORT_SYMBOL(csum_partial);
 EXPORT_SYMBOL(csum_partial_copy);

arch/ia64/include/asm/checksum.h

@@ -37,17 +37,6 @@ extern __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
  */
 extern __wsum csum_partial(const void *buff, int len, __wsum sum);
 
-#define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
-/*
- * Same as csum_partial, but copies from src while it checksums.
- *
- * Here it is even more important to align src and dst on a 32-bit (or
- * even better 64-bit) boundary.
- */
-extern __wsum csum_and_copy_from_user(const void __user *src, void *dst,
-						 int len, __wsum sum,
-						 int *errp);
-
 extern __wsum csum_partial_copy_nocheck(const void *src, void *dst,
 					       int len, __wsum sum);
 

arch/ia64/lib/csum_partial_copy.c

@@ -103,24 +103,6 @@ unsigned long do_csum_c(const unsigned char * buff, int len, unsigned int psum)
  * This is very ugly but temporary. THIS NEEDS SERIOUS ENHANCEMENTS.
  * But it's very tricky to get right even in C.
  */
-__wsum
-csum_and_copy_from_user(const void __user *src, void *dst,
-				int len, __wsum psum, int *errp)
-{
-	/* XXX Fixme
-	 * for now we separate the copy from checksum for obvious
-	 * alignment difficulties. Look at the Alpha code and you'll be
-	 * scared.
-	 */
-
-	if (copy_from_user(dst, src, len))
-		*errp = -EFAULT;
-
-	return csum_partial(dst, len, psum);
-}
-
-EXPORT_SYMBOL(csum_and_copy_from_user);
-
 __wsum
 csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
 {

arch/nios2/include/asm/checksum.h

@@ -14,8 +14,6 @@
 extern __wsum csum_partial(const void *buff, int len, __wsum sum);
 extern __wsum csum_partial_copy(const void *src, void *dst, int len,
 				__wsum sum);
-extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst,
-					int len, __wsum sum, int *csum_err);
 #define csum_partial_copy_nocheck(src, dst, len, sum)	\
 	csum_partial_copy((src), (dst), (len), (sum))
 

arch/parisc/include/asm/checksum.h

@@ -26,14 +26,6 @@ extern __wsum csum_partial(const void *, int, __wsum);
  */
 extern __wsum csum_partial_copy_nocheck(const void *, void *, int, __wsum);
 
-#define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
-/*
- * 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 __wsum csum_and_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.
  *

arch/parisc/lib/checksum.c

@@ -123,17 +123,3 @@ __wsum csum_partial_copy_nocheck(const void *src, void *dst,
 	return sum;
 }
 EXPORT_SYMBOL(csum_partial_copy_nocheck);
-
-/*
- * Copy from userspace and compute checksum.  If we catch an exception
- * then zero the rest of the buffer.
- */
-__wsum csum_and_copy_from_user(const void __user *src,
-					void *dst, int len,
-					__wsum sum, int *err_ptr)
-{
-	if (copy_from_user(dst, src, len))
-		*err_ptr = -EFAULT;
-	return csum_partial(dst, len, sum);
-}
-EXPORT_SYMBOL(csum_and_copy_from_user);

arch/s390/include/asm/checksum.h

@@ -39,25 +39,6 @@ csum_partial(const void *buff, int len, __wsum sum)
 	return sum;
 }
 
-/*
- * the same as csum_partial_copy, but copies from user space.
- *
- * here even more important to align src and dst on a 32-bit (or even
- * better 64-bit) boundary
- *
- * Copy from userspace and compute checksum.
- */
-static inline __wsum
-csum_partial_copy_from_user(const void __user *src, void *dst,
-                                          int len, __wsum sum,
-                                          int *err_ptr)
-{
-	if (unlikely(copy_from_user(dst, src, len)))
-		*err_ptr = -EFAULT;
-	return csum_partial(dst, len, sum);
-}
-
-
 static inline __wsum
 csum_partial_copy_nocheck (const void *src, void *dst, int len, __wsum sum)
 {

arch/x86/um/asm/checksum.h

@@ -36,26 +36,6 @@ __wsum csum_partial_copy_nocheck(const void *src, void *dst,
 	return csum_partial(dst, len, sum);
 }
 
-/*
- * the same as csum_partial, but copies from src while it
- * checksums, and handles user-space pointer exceptions correctly, when needed.
- *
- * here even more important to align src and dst on a 32-bit (or even
- * better 64-bit) boundary
- */
-
-static __inline__
-__wsum csum_partial_copy_from_user(const void __user *src, void *dst,
-					 int len, __wsum sum, int *err_ptr)
-{
-	if (copy_from_user(dst, src, len)) {
-		*err_ptr = -EFAULT;
-		return (__force __wsum)-1;
-	}
-
-	return csum_partial(dst, len, sum);
-}
-
 /**
  * csum_fold - Fold and invert a 32bit checksum.
  * sum: 32bit unfolded sum

include/asm-generic/checksum.h

@@ -25,15 +25,6 @@ extern __wsum csum_partial(const void *buff, int len, __wsum sum);
  */
 extern __wsum csum_partial_copy(const void *src, void *dst, int len, __wsum sum);
 
-/*
- * the same as csum_partial_copy, but copies from user space.
- *
- * here even more important to align src and dst on a 32-bit (or even
- * better 64-bit) boundary
- */
-extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst,
-					int len, __wsum sum, int *csum_err);
-
 #ifndef csum_partial_copy_nocheck
 #define csum_partial_copy_nocheck(src, dst, len, sum)	\
 	csum_partial_copy((src), (dst), (len), (sum))

include/net/checksum.h

@@ -26,13 +26,9 @@ static inline
 __wsum csum_and_copy_from_user (const void __user *src, void *dst,
 				      int len, __wsum sum, int *err_ptr)
 {
-	if (access_ok(src, len))
-		return csum_partial_copy_from_user(src, dst, len, sum, err_ptr);
-
-	if (len)
+	if (copy_from_user(dst, src, len))
 		*err_ptr = -EFAULT;
-
-	return sum;
+	return csum_partial(dst, len, sum);
 }
 #endif
 

lib/checksum.c

@@ -145,26 +145,6 @@ __sum16 ip_compute_csum(const void *buff, int len)
 }
 EXPORT_SYMBOL(ip_compute_csum);
 
-/*
- * copy from fs while checksumming, otherwise like csum_partial
- */
-__wsum
-csum_partial_copy_from_user(const void __user *src, void *dst, int len,
-						__wsum sum, int *csum_err)
-{
-	int missing;
-
-	missing = __copy_from_user(dst, src, len);
-	if (missing) {
-		memset(dst + len - missing, 0, missing);
-		*csum_err = -EFAULT;
-	} else
-		*csum_err = 0;
-
-	return csum_partial(dst, len, sum);
-}
-EXPORT_SYMBOL(csum_partial_copy_from_user);
-
 /*
  * copy from ds while checksumming, otherwise like csum_partial
  */