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[3.19.y-ckt,stable] Patch "lib: lz4: fixed zram with lz4 on big endian machines" has been added to the 3.19.y-ckt tree

Message ID 1461700441-4190-1-git-send-email-kamal@canonical.com
State New
Headers show

Commit Message

Kamal Mostafa April 26, 2016, 7:54 p.m. UTC 
This is a note to let you know that I have just added a patch titled

    lib: lz4: fixed zram with lz4 on big endian machines

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt20.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

---8<------------------------------------------------------------

From 9cbbd5aa36bce6094afa8ff7e87418129f7e6ce4 Mon Sep 17 00:00:00 2001
From: Rui Salvaterra <rsalvaterra@gmail.com>
Date: Sat, 9 Apr 2016 22:05:34 +0100
Subject: lib: lz4: fixed zram with lz4 on big endian machines

commit 3e26a691fe3fe1e02a76e5bab0c143ace4b137b4 upstream.

Based on Sergey's test patch [1], this fixes zram with lz4 compression
on big endian cpus.

Note that the 64-bit preprocessor test is not a cleanup, it's part of
the fix, since those identifiers are bogus (for example, __ppc64__
isn't defined anywhere else in the kernel, which means we'd fall into
the 32-bit definitions on ppc64).

Tested on ppc64 with no regression on x86_64.

[1] http://marc.info/?l=linux-kernel&m=145994470805853&w=4

Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Rui Salvaterra <rsalvaterra@gmail.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
 lib/lz4/lz4defs.h | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

--
2.7.4
diff mbox

Patch

diff --git a/lib/lz4/lz4defs.h b/lib/lz4/lz4defs.h
index abcecdc..0710a62 100644
--- a/lib/lz4/lz4defs.h
+++ b/lib/lz4/lz4defs.h
@@ -11,8 +11,7 @@ 
 /*
  * Detects 64 bits mode
  */
-#if (defined(__x86_64__) || defined(__x86_64) || defined(__amd64__) \
-	|| defined(__ppc64__) || defined(__LP64__))
+#if defined(CONFIG_64BIT)
 #define LZ4_ARCH64 1
 #else
 #define LZ4_ARCH64 0
@@ -35,6 +34,10 @@  typedef struct _U64_S { u64 v; } U64_S;

 #define PUT4(s, d) (A32(d) = A32(s))
 #define PUT8(s, d) (A64(d) = A64(s))
+
+#define LZ4_READ_LITTLEENDIAN_16(d, s, p)	\
+	(d = s - A16(p))
+
 #define LZ4_WRITE_LITTLEENDIAN_16(p, v)	\
 	do {	\
 		A16(p) = v; \
@@ -51,10 +54,13 @@  typedef struct _U64_S { u64 v; } U64_S;
 #define PUT8(s, d) \
 	put_unaligned(get_unaligned((const u64 *) s), (u64 *) d)

-#define LZ4_WRITE_LITTLEENDIAN_16(p, v)	\
-	do {	\
-		put_unaligned(v, (u16 *)(p)); \
-		p += 2; \
+#define LZ4_READ_LITTLEENDIAN_16(d, s, p)	\
+	(d = s - get_unaligned_le16(p))
+
+#define LZ4_WRITE_LITTLEENDIAN_16(p, v)			\
+	do {						\
+		put_unaligned_le16(v, (u16 *)(p));	\
+		p += 2;					\
 	} while (0)
 #endif

@@ -140,9 +146,6 @@  typedef struct _U64_S { u64 v; } U64_S;

 #endif

-#define LZ4_READ_LITTLEENDIAN_16(d, s, p) \
-	(d = s - get_unaligned_le16(p))
-
 #define LZ4_WILDCOPY(s, d, e)		\
 	do {				\
 		LZ4_COPYPACKET(s, d);	\