s390/dump: introduce boot data 'oldmem_data'

The new boot data struct shall replace global variables OLDMEM_BASE and
OLDMEM_SIZE. It is initialized in the decompressor and passed
to the decompressed kernel. In comparison to the old solution, this one
doesn't access data at fixed physical addresses which will become important
when the decompressor becomes relocatable.

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c
index 694780339db0..6206ca149d5e 100644
--- a/arch/s390/boot/startup.c
+++ b/arch/s390/boot/startup.c
@@ -27,6 +27,7 @@ struct initrd_data __bootdata(initrd_data);
 
 u64 __bootdata_preserved(stfle_fac_list[16]);
 u64 __bootdata_preserved(alt_stfle_fac_list[16]);
+struct oldmem_data __bootdata_preserved(oldmem_data);
 
 /*
  * Some code and data needs to stay below 2 GB, even when the kernel would be
@@ -165,9 +166,9 @@ static void setup_ident_map_size(unsigned long max_physmem_end)
 	ident_map_size = min(ident_map_size, 1UL << MAX_PHYSMEM_BITS);
 
 #ifdef CONFIG_CRASH_DUMP
-	if (OLDMEM_BASE) {
+	if (oldmem_data.start) {
 		kaslr_enabled = 0;
-		ident_map_size = min(ident_map_size, OLDMEM_SIZE);
+		ident_map_size = min(ident_map_size, oldmem_data.size);
 	} else if (ipl_block_valid && is_ipl_block_dump()) {
 		kaslr_enabled = 0;
 		if (!sclp_early_get_hsa_size(&hsa_size) && hsa_size)
@@ -286,6 +287,8 @@ void startup_kernel(void)
 
 	initrd_data.start = parmarea.initrd_start;
 	initrd_data.size = parmarea.initrd_size;
+	oldmem_data.start = parmarea.oldmem_base;
+	oldmem_data.size = parmarea.oldmem_size;
 
 	setup_lpp();
 	store_ipl_parmblock();