[S390] support XZ compressed kernel

Add support for XZ compressed kernel. Same as on x86 and sh.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/Kconfig

@@ -85,6 +85,7 @@ config S390
 	select HAVE_KERNEL_BZIP2
 	select HAVE_KERNEL_LZMA
 	select HAVE_KERNEL_LZO
+	select HAVE_KERNEL_XZ
 	select HAVE_GET_USER_PAGES_FAST
 	select HAVE_ARCH_MUTEX_CPU_RELAX
 	select ARCH_INLINE_SPIN_TRYLOCK

arch/s390/boot/compressed/Makefile

@@ -7,7 +7,8 @@
 BITS := $(if $(CONFIG_64BIT),64,31)
 
 targets	:= vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 \
-	   vmlinux.bin.lzma vmlinux.bin.lzo misc.o piggy.o sizes.h head$(BITS).o
+	   vmlinux.bin.xz vmlinux.bin.lzma vmlinux.bin.lzo misc.o piggy.o \
+	   sizes.h head$(BITS).o
 
 KBUILD_CFLAGS := -m$(BITS) -D__KERNEL__ $(LINUX_INCLUDE) -O2
 KBUILD_CFLAGS += $(cflags-y)
@@ -48,6 +49,7 @@ suffix-$(CONFIG_KERNEL_GZIP)  := gz
 suffix-$(CONFIG_KERNEL_BZIP2) := bz2
 suffix-$(CONFIG_KERNEL_LZMA)  := lzma
 suffix-$(CONFIG_KERNEL_LZO)  := lzo
+suffix-$(CONFIG_KERNEL_XZ)  := xz
 
 $(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y)
 	$(call if_changed,gzip)
@@ -57,6 +59,8 @@ $(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y)
 	$(call if_changed,lzma)
 $(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y)
 	$(call if_changed,lzo)
+$(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y)
+	$(call if_changed,xzkern)
 
 LDFLAGS_piggy.o := -r --format binary --oformat $(LD_BFD) -T
 $(obj)/piggy.o: $(obj)/vmlinux.scr $(obj)/vmlinux.bin.$(suffix-y)

arch/s390/boot/compressed/misc.c

@@ -19,6 +19,7 @@
 #undef memset
 #undef memcpy
 #undef memmove
+#define memmove memmove
 #define memzero(s, n) memset((s), 0, (n))
 
 /* Symbols defined by linker scripts */
@@ -54,6 +55,10 @@ static unsigned long free_mem_end_ptr;
 #include "../../../../lib/decompress_unlzo.c"
 #endif
 
+#ifdef CONFIG_KERNEL_XZ
+#include "../../../../lib/decompress_unxz.c"
+#endif
+
 extern _sclp_print_early(const char *);
 
 int puts(const char *s)