s390: unify identity mapping limits handling

Currently we have to consider too many different values which
in the end only affect identity mapping size. These are:
1. max_physmem_end - end of physical memory online or standby.
   Always <= end of the last online memory block (get_mem_detect_end()).
2. CONFIG_MAX_PHYSMEM_BITS - the maximum size of physical memory the
   kernel is able to support.
3. "mem=" kernel command line option which limits physical memory usage.
4. OLDMEM_BASE which is a kdump memory limit when the kernel is executed as
   crash kernel.
5. "hsa" size which is a memory limit when the kernel is executed during
   zfcp/nvme dump.

Through out kernel startup and run we juggle all those values at once
but that does not bring any amusement, only confusion and complexity.

Unify all those values to a single one we should really care, that is
our identity mapping size.

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

1 files changed, 14 insertions, 30 deletions

diff --git a/arch/s390/boot/ipl_parm.c b/arch/s390/boot/ipl_parm.c
index 33f43a7d03f3..d372a45fe10e 100644
--- a/arch/s390/boot/ipl_parm.c
+++ b/arch/s390/boot/ipl_parm.c
@@ -17,10 +17,9 @@ int __bootdata_preserved(ipl_block_valid);
 unsigned int __bootdata_preserved(zlib_dfltcc_support) = ZLIB_DFLTCC_FULL;
 
 unsigned long __bootdata(vmalloc_size) = VMALLOC_DEFAULT_SIZE;
-unsigned long __bootdata(memory_end);
-int __bootdata(memory_end_set);
 int __bootdata(noexec_disabled);
 
+unsigned long memory_limit;
 int vmalloc_size_set;
 int kaslr_enabled;
 
@@ -58,6 +57,17 @@ void store_ipl_parmblock(void)
 		ipl_block_valid = 1;
 }
 
+bool is_ipl_block_dump(void)
+{
+	if (ipl_block.pb0_hdr.pbt == IPL_PBT_FCP &&
+	    ipl_block.fcp.opt == IPL_PB0_FCP_OPT_DUMP)
+		return true;
+	if (ipl_block.pb0_hdr.pbt == IPL_PBT_NVME &&
+	    ipl_block.nvme.opt == IPL_PB0_NVME_OPT_DUMP)
+		return true;
+	return false;
+}
+
 static size_t scpdata_length(const u8 *buf, size_t count)
 {
 	while (count) {
@@ -238,10 +248,8 @@ void parse_boot_command_line(void)
 	while (*args) {
 		args = next_arg(args, &param, &val);
 
-		if (!strcmp(param, "mem") && val) {
-			memory_end = round_down(memparse(val, NULL), PAGE_SIZE);
-			memory_end_set = 1;
-		}
+		if (!strcmp(param, "mem") && val)
+			memory_limit = round_down(memparse(val, NULL), PAGE_SIZE);
 
 		if (!strcmp(param, "vmalloc") && val) {
 			vmalloc_size = round_up(memparse(val, NULL), PAGE_SIZE);
@@ -282,27 +290,3 @@ void parse_boot_command_line(void)
 #endif
 	}
 }
-
-static inline bool is_ipl_block_dump(void)
-{
-	if (ipl_block.pb0_hdr.pbt == IPL_PBT_FCP &&
-	    ipl_block.fcp.opt == IPL_PB0_FCP_OPT_DUMP)
-		return true;
-	if (ipl_block.pb0_hdr.pbt == IPL_PBT_NVME &&
-	    ipl_block.nvme.opt == IPL_PB0_NVME_OPT_DUMP)
-		return true;
-	return false;
-}
-
-void setup_memory_end(void)
-{
-#ifdef CONFIG_CRASH_DUMP
-	if (OLDMEM_BASE) {
-		kaslr_enabled = 0;
-	} else if (ipl_block_valid && is_ipl_block_dump()) {
-		kaslr_enabled = 0;
-		if (!sclp_early_get_hsa_size(&memory_end) && memory_end)
-			memory_end_set = 1;
-	}
-#endif
-}