x86: rename and clean up __copy_from_user_inatomic_nocache()

commit 5de7bcaadf160c1716b20a263cf8f5b06f658959 upstream.

Similarly to the previous commit, this renames the somewhat confusingly
named function.  But in this case, it was at least less confusing: the
__copy_from_user_inatomic_nocache is indeed copying from user memory,
and it is indeed ok to be used in an atomic context, so it will not warn
about it.

But the previous commit also removed the NTB mis-use of the
__copy_from_user_inatomic_nocache() function, and as a result every
call-site is now _actually_ doing a real user copy.  That means that we
can now do the proper user pointer verification too.

End result: add proper address checking, remove the double underscores,
and change the "nocache" to "nontemporal" to more accurately describe
what this x86-only function actually does.  It might be worth noting
that only the target is non-temporal: the actual user accesses are
normal memory accesses.

Also worth noting is that non-x86 targets (and on older 32-bit x86 CPU's
before XMM2 in the Pentium III) we end up just falling back on a regular
user copy, so nothing can actually depend on the non-temporal semantics,
but that has always been true.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 0a63c7fba313..5bc04579303b 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -277,7 +277,7 @@ static __always_inline
 size_t copy_from_user_iter_nocache(void __user *iter_from, size_t progress,
 				   size_t len, void *to, void *priv2)
 {
-	return __copy_from_user_inatomic_nocache(to + progress, iter_from, len);
+	return copy_from_user_inatomic_nontemporal(to + progress, iter_from, len);
 }
 
 size_t _copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i)