[PATCH v20 2/5] arm64: kdump: introduce some macros for crash kernel reservation

[Zhen Lei <thunder.leizhen@huawei.com>]

From: Chen Zhou <chenzhou10@huawei.com>

Introduce macro CRASH_ALIGN for alignment, macro CRASH_ADDR_LOW_MAX
for upper bound of low crash memory, macro CRASH_ADDR_HIGH_MAX for
upper bound of high crash memory, use macros instead.

Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Tested-by: John Donnelly <John.p.donnelly@oracle.com>
Tested-by: Dave Kleikamp <dave.kleikamp@oracle.com>
---
 arch/arm64/mm/init.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 90f276d46b93bc6..6c653a2c7cff052 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -65,6 +65,12 @@ EXPORT_SYMBOL(memstart_addr);
 phys_addr_t arm64_dma_phys_limit __ro_after_init;
 
 #ifdef CONFIG_KEXEC_CORE
+/* Current arm64 boot protocol requires 2MB alignment */
+#define CRASH_ALIGN		SZ_2M
+
+#define CRASH_ADDR_LOW_MAX	arm64_dma_phys_limit
+#define CRASH_ADDR_HIGH_MAX	MEMBLOCK_ALLOC_ACCESSIBLE
+
 /*
  * reserve_crashkernel() - reserves memory for crash kernel
  *
@@ -75,7 +81,7 @@ phys_addr_t arm64_dma_phys_limit __ro_after_init;
 static void __init reserve_crashkernel(void)
 {
 	unsigned long long crash_base, crash_size;
-	unsigned long long crash_max = arm64_dma_phys_limit;
+	unsigned long long crash_max = CRASH_ADDR_LOW_MAX;
 	int ret;
 
 	ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
@@ -90,8 +96,7 @@ static void __init reserve_crashkernel(void)
 	if (crash_base)
 		crash_max = crash_base + crash_size;
 
-	/* Current arm64 boot protocol requires 2MB alignment */
-	crash_base = memblock_phys_alloc_range(crash_size, SZ_2M,
+	crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN,
 					       crash_base, crash_max);
 	if (!crash_base) {
 		pr_warn("cannot allocate crashkernel (size:0x%llx)\n",
-- 
2.25.1