From: Heiko Carstens <hca@linux.ibm.com>
Date: Fri, 7 May 2021 17:12:39 +0000 (+0200)
Subject: s390/ipl: make parameter area accessible via struct parmarea
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=f73c632d387a5f1528cca6032c646489610bec13;p=linux.git

s390/ipl: make parameter area accessible via struct parmarea

Since commit 9a965ea95135 ("s390/kexec_file: Simplify parmarea
access") we have struct parmarea which describes the layout of the
kernel parameter area.

Make the kernel parameter area available as global variable parmarea
of type struct parmarea, which allows to easily access its members.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
---

diff --git a/arch/s390/boot/head.S b/arch/s390/boot/head.S
index dacb7813f9825..51693cfb65c2c 100644
--- a/arch/s390/boot/head.S
+++ b/arch/s390/boot/head.S
@@ -401,6 +401,7 @@ SYM_CODE_END(startup_pgm_check_handler)
 # Must be keept in sync with struct parmarea in setup.h
 #
 	.org	PARMAREA
+SYM_DATA_START(parmarea)
 	.quad	0			# IPL_DEVICE
 	.quad	0			# INITRD_START
 	.quad	0			# INITRD_SIZE
@@ -411,6 +412,8 @@ SYM_CODE_END(startup_pgm_check_handler)
 	.org	COMMAND_LINE
 	.byte	"root=/dev/ram0 ro"
 	.byte	0
+	.org	PARMAREA+__PARMAREA_SIZE
+SYM_DATA_END(parmarea)
 
 	.org	EARLY_SCCB_OFFSET
 	.fill	4096
diff --git a/arch/s390/include/asm/setup.h b/arch/s390/include/asm/setup.h
index 3e388fa208d4f..29baab03f0919 100644
--- a/arch/s390/include/asm/setup.h
+++ b/arch/s390/include/asm/setup.h
@@ -78,6 +78,8 @@ struct parmarea {
 	char command_line[ARCH_COMMAND_LINE_SIZE];	/* 0x10480 */
 };
 
+extern struct parmarea parmarea;
+
 extern unsigned int zlib_dfltcc_support;
 #define ZLIB_DFLTCC_DISABLED		0
 #define ZLIB_DFLTCC_FULL		1
diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c
index b4ca7cc011cb4..f53605a3dfcdc 100644
--- a/arch/s390/kernel/asm-offsets.c
+++ b/arch/s390/kernel/asm-offsets.c
@@ -15,6 +15,7 @@
 #include <asm/idle.h>
 #include <asm/gmap.h>
 #include <asm/nmi.h>
+#include <asm/setup.h>
 #include <asm/stacktrace.h>
 
 int main(void)
@@ -155,5 +156,7 @@ int main(void)
 	OFFSET(__KEXEC_SHA_REGION_START, kexec_sha_region, start);
 	OFFSET(__KEXEC_SHA_REGION_LEN, kexec_sha_region, len);
 	DEFINE(__KEXEC_SHA_REGION_SIZE, sizeof(struct kexec_sha_region));
+	/* sizeof kernel parameter area */
+	DEFINE(__PARMAREA_SIZE, sizeof(struct parmarea));
 	return 0;
 }