[S390] kernel: Add OS info memory interface

In order to allow kdump based stand-alone dump, some information
has to be passed from the old kernel to the new dump kernel. This
is done via a the struct "os_info" that contains the following fields:
 * crashkernel base and size
 * reipl block
 * vmcoreinfo
 * init function
A pointer to os_info is stored at a well known storage location
and the whole structure as well as all fields are secured with
checksums.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 9a3edb5..38e7512 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -62,6 +62,7 @@
 #include <asm/ebcdic.h>
 #include <asm/kvm_virtio.h>
 #include <asm/diag.h>
+#include <asm/os_info.h>
 #include "entry.h"
 
 long psw_kernel_bits	= PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_ASC_PRIMARY |
@@ -778,6 +779,7 @@
 	pr_info("Reserving %lluMB of memory at %lluMB "
 		"for crashkernel (System RAM: %luMB)\n",
 		crash_size >> 20, crash_base >> 20, memory_end >> 20);
+	os_info_crashkernel_add(crash_base, crash_size);
 #endif
 }
 
@@ -1057,6 +1059,7 @@
 
 	parse_early_param();
 
+	os_info_init();
 	setup_ipl();
 	setup_memory_end();
 	setup_addressing_mode();