s390: setup kernel memory layout early

Currently there are two separate places where kernel memory layout has
to be known and adjusted:
1. early kasan setup.
2. paging setup later.

Those 2 places had to be kept in sync and adjusted to reflect peculiar
technical details of one another. With additional factors which influence
kernel memory layout like ultravisor secure storage limit, complexity
of keeping two things in sync grew up even more.

Besides that if we look forward towards creating identity mapping and
enabling DAT before jumping into uncompressed kernel - that would also
require full knowledge of and control over kernel memory layout.

So, de-duplicate and move kernel memory layout setup logic into
the decompressor.

Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/arch/s390/boot/boot.h b/arch/s390/boot/boot.h
index 8b50967f5804..ae04e1c93764 100644
--- a/arch/s390/boot/boot.h
+++ b/arch/s390/boot/boot.h
@@ -24,6 +24,7 @@ void __printf(1, 2) decompressor_printk(const char *fmt, ...);
 
 extern const char kernel_version[];
 extern unsigned long memory_limit;
+extern unsigned long vmalloc_size;
 extern int vmalloc_size_set;
 extern int kaslr_enabled;