From fdf23ed283bc6ef5c25076ce2065f892120ff556 Mon Sep 17 00:00:00 2001
From: Phillip Lougher <phillip@lougher.demon.co.uk>
Date: Thu, 22 Oct 2009 04:57:38 +0100
Subject: [PATCH] Squashfs: Make unlzma available to non initramfs/initrd code

Add a config option DECOMPRESS_LZMA_NEEDED which allows subsystems to
specify they need the unlzma code.  Normally decompress_unlzma.c is
compiled with __init and unlzma is not exported to modules.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
---
 fs/squashfs/Kconfig                   |    1 +
 include/linux/decompress/bunzip2_mm.h |   12 ++++++++++++
 include/linux/decompress/inflate_mm.h |   12 ++++++++++++
 include/linux/decompress/mm.h         |    3 ---
 include/linux/decompress/unlzma_mm.h  |   20 ++++++++++++++++++++
 lib/Kconfig                           |    3 +++
 lib/decompress_bunzip2.c              |    1 +
 lib/decompress_inflate.c              |    1 +
 lib/decompress_unlzma.c               |    5 ++++-
 9 files changed, 54 insertions(+), 4 deletions(-)
 create mode 100644 include/linux/decompress/bunzip2_mm.h
 create mode 100644 include/linux/decompress/inflate_mm.h
 create mode 100644 include/linux/decompress/unlzma_mm.h

--- a/fs/squashfs/Kconfig
+++ b/fs/squashfs/Kconfig
@@ -30,6 +30,7 @@ config SQUASHFS_LZMA
 	bool "Include support for LZMA compressed file systems"
 	depends on SQUASHFS
 	select DECOMPRESS_LZMA
+	select DECOMPRESS_LZMA_NEEDED
 
 config SQUASHFS_EMBEDDED
 
--- /dev/null
+++ b/include/linux/decompress/bunzip2_mm.h
@@ -0,0 +1,12 @@
+#ifndef BUNZIP2_MM_H
+#define BUNZIP2_MM_H
+
+#ifdef STATIC
+/* Code active when included from pre-boot environment: */
+#define INIT
+#else
+/* Compile for initramfs/initrd code only */
+#define INIT __init
+#endif
+
+#endif
--- /dev/null
+++ b/include/linux/decompress/inflate_mm.h
@@ -0,0 +1,12 @@
+#ifndef INFLATE_MM_H
+#define INFLATE_MM_H
+
+#ifdef STATIC
+/* Code active when included from pre-boot environment: */
+#define INIT
+#else
+/* Compile for initramfs/initrd code only */
+#define INIT __init
+#endif
+
+#endif
--- a/include/linux/decompress/mm.h
+++ b/include/linux/decompress/mm.h
@@ -53,8 +53,6 @@ static void free(void *where)
 
 #define set_error_fn(x)
 
-#define INIT
-
 #else /* STATIC */
 
 /* Code active when compiled standalone for use when loading ramdisk: */
@@ -77,7 +75,6 @@ static void free(void *where)
 static void(*error)(char *m);
 #define set_error_fn(x) error = x;
 
-#define INIT __init
 #define STATIC
 
 #include <linux/init.h>
--- /dev/null
+++ b/include/linux/decompress/unlzma_mm.h
@@ -0,0 +1,20 @@
+#ifndef UNLZMA_MM_H
+#define UNLZMA_MM_H
+
+#ifdef STATIC
+
+/* Code active when included from pre-boot environment: */
+#define INIT
+
+#elif defined(CONFIG_DECOMPRESS_LZMA_NEEDED)
+
+/* Make it available to non initramfs/initrd code */
+#define INIT
+#include <linux/module.h>
+#else
+
+/* Compile for initramfs/initrd code only */
+#define INIT __init
+#endif
+
+#endif
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -117,6 +117,9 @@ config DECOMPRESS_BZIP2
 config DECOMPRESS_LZMA
 	tristate
 
+config DECOMPRESS_LZMA_NEEDED
+	 boolean
+
 #
 # Generic allocator support is selected if needed
 #
--- a/lib/decompress_bunzip2.c
+++ b/lib/decompress_bunzip2.c
@@ -52,6 +52,7 @@
 #include <linux/slab.h>
 #endif /* STATIC */
 
+#include <linux/decompress/bunzip2_mm.h>
 #include <linux/decompress/mm.h>
 
 #ifndef INT_MAX
--- a/lib/decompress_inflate.c
+++ b/lib/decompress_inflate.c
@@ -23,6 +23,7 @@
 
 #endif /* STATIC */
 
+#include <linux/decompress/inflate_mm.h>
 #include <linux/decompress/mm.h>
 
 #define GZIP_IOBUF_SIZE (16*1024)
--- a/lib/decompress_unlzma.c
+++ b/lib/decompress_unlzma.c
@@ -36,6 +36,7 @@
 #include <linux/slab.h>
 #endif /* STATIC */
 
+#include <linux/decompress/unlzma_mm.h>
 #include <linux/decompress/mm.h>
 
 #define	MIN(a, b) (((a) < (b)) ? (a) : (b))
@@ -523,7 +524,7 @@ static inline void INIT process_bit1(str
 
 
 
-STATIC inline int INIT unlzma(unsigned char *buf, int in_len,
+STATIC int INIT unlzma(unsigned char *buf, int in_len,
 			      int(*fill)(void*, unsigned int),
 			      int(*flush)(void*, unsigned int),
 			      unsigned char *output,
@@ -656,4 +657,6 @@ STATIC int INIT decompress(unsigned char
 {
 	return unlzma(buf, in_len - 4, fill, flush, output, posp, error_fn);
 }
+#elif defined(CONFIG_DECOMPRESS_LZMA_NEEDED)
+EXPORT_SYMBOL(unlzma);
 #endif
