Patch "word-at-a-time.h: support zero_bytemask() on alpha and tile" has been added to the 3.18-stable tree

Patch "word-at-a-time.h: support zero_bytemask() on alpha and tile" has been added to the 3.18-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    word-at-a-time.h: support zero_bytemask() on alpha and tile

to the 3.18-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     word-at-a-time.h-support-zero_bytemask-on-alpha-and-tile.patch
and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From c753bf34c94e5ac901e625e52f47320eeec4de2d Mon Sep 17 00:00:00 2001
From: Chris Metcalf <cmetcalf@ezchip.com>
Date: Tue, 6 Oct 2015 14:20:45 -0400
Subject: word-at-a-time.h: support zero_bytemask() on alpha and tile

From: Chris Metcalf <cmetcalf@ezchip.com>

commit c753bf34c94e5ac901e625e52f47320eeec4de2d upstream.

Both alpha and tile needed implementations of zero_bytemask.

The alpha version is untested.

Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/alpha/include/asm/word-at-a-time.h |    2 ++
 arch/tile/include/asm/word-at-a-time.h  |    8 +++++++-
 2 files changed, 9 insertions(+), 1 deletion(-)

--- a/arch/alpha/include/asm/word-at-a-time.h
+++ b/arch/alpha/include/asm/word-at-a-time.h
@@ -52,4 +52,6 @@ static inline unsigned long find_zero(un
 #endif
 }
 
+#define zero_bytemask(mask) ((2ul << (find_zero(mask) * 8)) - 1)
+
 #endif /* _ASM_WORD_AT_A_TIME_H */
--- a/arch/tile/include/asm/word-at-a-time.h
+++ b/arch/tile/include/asm/word-at-a-time.h
@@ -6,7 +6,7 @@
 struct word_at_a_time { /* unused */ };
 #define WORD_AT_A_TIME_CONSTANTS {}
 
-/* Generate 0x01 byte values for non-zero bytes using a SIMD instruction. */
+/* Generate 0x01 byte values for zero bytes using a SIMD instruction. */
 static inline unsigned long has_zero(unsigned long val, unsigned long *data,
 				     const struct word_at_a_time *c)
 {
@@ -33,4 +33,10 @@ static inline long find_zero(unsigned lo
 #endif
 }
 
+#ifdef __BIG_ENDIAN
+#define zero_bytemask(mask) (~1ul << (63 - __builtin_clzl(mask)))
+#else
+#define zero_bytemask(mask) ((2ul << __builtin_ctzl(mask)) - 1)
+#endif
+
 #endif /* _ASM_WORD_AT_A_TIME_H */


Patches currently in stable-queue which might be from cmetcalf@ezchip.com are

queue-3.18/strscpy-zero-any-trailing-garbage-bytes-in-the-destination.patch
queue-3.18/word-at-a-time.h-support-zero_bytemask-on-alpha-and-tile.patch
queue-3.18/tile-add-asm-word-at-a-time.h-and-enable-support-functions.patch
queue-3.18/string-provide-strscpy.patch