initramfs: support initramfs that is bigger than 2GiB

Now with 64bit bzImage and kexec tools, we support ramdisk that size is
bigger than 2g, as we could put it above 4G.

Found compressed initramfs image could not be decompressed properly.  It
turns out that image length is int during decompress detection, and it
will become < 0 when length is more than 2G.  Furthermore, during
decompressing len as int is used for inbuf count, that has problem too.

Change len to long, that should be ok as on 32 bit platform long is
32bits.

Tested with following compressed initramfs image as root with kexec.
	gzip, bzip2, xz, lzma, lzop, lz4.
run time for populate_rootfs():
   size        name       Nehalem-EX  Westmere-EX  Ivybridge-EX
 9034400256 root_img     :   26s           24s          30s
 3561095057 root_img.lz4 :   28s           27s          27s
 3459554629 root_img.lzo :   29s           29s          28s
 3219399480 root_img.gz  :   64s           62s          49s
 2251594592 root_img.xz  :  262s          260s         183s
 2226366598 root_img.lzma:  386s          376s         277s
 2901482513 root_img.bz2 :  635s          599s

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Rashika Kheria <rashika.kheria@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: P J P <ppandit@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: "Daniel M. Weeks" <dan@danweeks.net>
Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 6 deletions

diff --git a/lib/decompress_inflate.c b/lib/decompress_inflate.c
index 0edfd742a154..d4c7891635ec 100644
--- a/lib/decompress_inflate.c
+++ b/lib/decompress_inflate.c
@@ -27,17 +27,17 @@
 
 #define GZIP_IOBUF_SIZE (16*1024)
 
-static int INIT nofill(void *buffer, unsigned int len)
+static long INIT nofill(void *buffer, unsigned long len)
 {
 	return -1;
 }
 
 /* Included from initramfs et al code */
-STATIC int INIT gunzip(unsigned char *buf, int len,
-		       int(*fill)(void*, unsigned int),
-		       int(*flush)(void*, unsigned int),
+STATIC int INIT gunzip(unsigned char *buf, long len,
+		       long (*fill)(void*, unsigned long),
+		       long (*flush)(void*, unsigned long),
 		       unsigned char *out_buf,
-		       int *pos,
+		       long *pos,
 		       void(*error)(char *x)) {
 	u8 *zbuf;
 	struct z_stream_s *strm;
@@ -142,7 +142,7 @@ STATIC int INIT gunzip(unsigned char *buf, int len,
 
 		/* Write any data generated */
 		if (flush && strm->next_out > out_buf) {
-			int l = strm->next_out - out_buf;
+			long l = strm->next_out - out_buf;
 			if (l != flush(out_buf, l)) {
 				rc = -1;
 				error("write error");