x86-64/arm64/powerpc: clean up and rename __copy_from_user_flushcachenocache-cleanup

This finishes the work on these odd functions that were only implemented
by a handful of architectures.

The 'flushcache' function was only used from the iterator code, and
let's make it do the same thing that the nontemporal version does:
remove the two underscores and add the user address checking.

Yes, yes, the user address checking is also done at iovec import time,
but we have long since walked away from the old double-underscore thing
where we try to avoid address checking overhead at access time, and
these functions shouldn't be so special and old-fashioned.

The arm64 version already did the address check, in fact, so there it's
just a matter of renaming it.  For powerpc and x86-64 we now do the
proper user access boilerplate.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 7 insertions, 7 deletions

diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index 784a00e681fa..c4221dae9750 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -405,8 +405,7 @@ copy_mc_to_user(void __user *to, const void *from, unsigned long n)
 }
 #endif
 
-extern long __copy_from_user_flushcache(void *dst, const void __user *src,
-		unsigned size);
+extern size_t copy_from_user_flushcache(void *dst, const void __user *src, size_t size);
 
 static __must_check __always_inline bool user_access_begin(const void __user *ptr, size_t len)
 {
diff --git a/arch/powerpc/lib/pmem.c b/arch/powerpc/lib/pmem.c
index 4e724c4c01ad..0f0f2d851ac6 100644
--- a/arch/powerpc/lib/pmem.c
+++ b/arch/powerpc/lib/pmem.c
@@ -66,15 +66,16 @@ EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
 /*
  * CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE symbols
  */
-long __copy_from_user_flushcache(void *dest, const void __user *src,
-		unsigned size)
+size_t copy_from_user_flushcache(void *dest, const void __user *src,
+				 size_t size)
 {
-	unsigned long copied, start = (unsigned long) dest;
+	unsigned long not_copied, start = (unsigned long) dest;
 
-	copied = __copy_from_user(dest, src, size);
+	src = mask_user_address(src);
+	not_copied = __copy_from_user(dest, src, size);
 	clean_pmem_range(start, start + size);
 
-	return copied;
+	return not_copied;
 }
 
 void memcpy_flushcache(void *dest, const void *src, size_t size)