tile: add <asm/word-at-a-time.h> and enable support functions
This change enables the generic strncpy_from_user() and strnlen_user()
using word-at-a-time.h. The tile implementation is trivial since
both tilepro and tilegx have SIMD operations that do byte-wise
comparisons against immediate zero for each byte, and return an
0x01 byte in each position where there is a 0x00 byte.
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig
index a07e31b..8fac40f 100644
--- a/arch/tile/Kconfig
+++ b/arch/tile/Kconfig
@@ -28,6 +28,8 @@
select HAVE_DEBUG_STACKOVERFLOW
select ARCH_WANT_FRAME_POINTERS
select HAVE_CONTEXT_TRACKING
+ select GENERIC_STRNCPY_FROM_USER
+ select GENERIC_STRNLEN_USER
# FIXME: investigate whether we need/want these options.
# select HAVE_IOREMAP_PROT