lib/decompress: Keep decompressor when CONFIG_KEEP_COMPRESSOR

The KEXE PE format parser needs the kernel built-in decompressor to
decompress the kernel image. So moving the decompressor out of __init
sections.

Signed-off-by: Pingfan Liu <[email protected]>
Cc: Andrew Morton <[email protected]>
To: [email protected]

Author: Pingfan Liu

include/linux/decompress/mm.h

@@ -92,7 +92,14 @@ MALLOC_VISIBLE void free(void *where)
 #define large_malloc(a) vmalloc(a)
 #define large_free(a) vfree(a)
 
+#ifdef CONFIG_KEEP_DECOMPRESSOR
+#define INIT
+#define INITCONST
+#else
 #define INIT __init
+#define INITCONST __initconst
+#endif
+
 #define STATIC
 
 #include <linux/init.h>

lib/Kconfig

@@ -165,6 +165,9 @@ config RANDOM32_SELFTEST
 #
 # compression support is select'ed if needed
 #
+config KEEP_DECOMPRESSOR
+	bool
+
 config 842_COMPRESS
 	select CRC32
 	tristate

lib/decompress.c

@@ -6,7 +6,7 @@
  */
 
 #include <linux/decompress/generic.h>
-
+#include <linux/decompress/mm.h>
 #include <linux/decompress/bunzip2.h>
 #include <linux/decompress/unlzma.h>
 #include <linux/decompress/unxz.h>
@@ -48,7 +48,7 @@ struct compress_format {
 	decompress_fn decompressor;
 };
 
-static const struct compress_format compressed_formats[] __initconst = {
+static const struct compress_format compressed_formats[] INITCONST = {
 	{ {0x1f, 0x8b}, "gzip", gunzip },
 	{ {0x1f, 0x9e}, "gzip", gunzip },
 	{ {0x42, 0x5a}, "bzip2", bunzip2 },
@@ -60,7 +60,7 @@ static const struct compress_format compressed_formats[] __initconst = {
 	{ {0, 0}, NULL, NULL }
 };
 
-decompress_fn __init decompress_method(const unsigned char *inbuf, long len,
+decompress_fn INIT decompress_method(const unsigned char *inbuf, long len,
 				const char **name)
 {
 	const struct compress_format *cf;