[PATCH v3 02/29] arc: introduce arch_zone_limits_init()

Mike Rapoport
2026-01-11T08:22:28Z

Move calculations of zone limits to a dedicated arch_zone_limits_init()
function.

Later MM core will use this function as an architecture specific callback
during nodes and zones initialization and thus there won't be a need to
call free_area_init() from every architecture.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Vineet Gupta <vgupta@kernel.org>
---
arch/arc/mm/init.c | 34 ++++++++++++++++++++--------------
1 file changed, 20 insertions(+), 14 deletions(-)

diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c
index a73cc94f806e..ff7974d38011 100644
--- a/arch/arc/mm/init.c
+++ b/arch/arc/mm/init.c
@@ -75,6 +75,25 @@ void __init early_init_dt_add_memory_arch(u64 base, u64 size)
base, TO_MB(size), !in_use ? "Not used":"");
}

+void __init arch_zone_limits_init(unsigned long *max_zone_pfn)
+{
+ /*----------------- node/zones setup --------------------------*/
+ max_zone_pfn[ZONE_NORMAL] = max_low_pfn;
+
+#ifdef CONFIG_HIGHMEM
+ /*
+ * max_high_pfn should be ok here for both HIGHMEM and HIGHMEM+PAE.
+ * For HIGHMEM without PAE max_high_pfn should be less than
+ * min_low_pfn to guarantee that these two regions don't overlap.
+ * For PAE case highmem is greater than lowmem, so it is natural
+ * to use max_high_pfn.
+ *
+ * In both cases, holes should be handled by pfn_valid().
+ */
+ max_zone_pfn[ZONE_HIGHMEM] = max_high_pfn;
+#endif
+}
+
/*
* First memory setup routine called from setup_arch()
* 1. setup swapper's mm @init_mm
@@ -122,9 +141,6 @@ void __init setup_arch_memory(void)

memblock_dump_all();

- /*----------------- node/zones setup --------------------------*/
- max_zone_pfn[ZONE_NORMAL] = max_low_pfn;
-
#ifdef CONFIG_HIGHMEM
/*
* On ARC (w/o PAE) HIGHMEM addresses are actually smaller (0 based)
@@ -139,21 +155,11 @@ void __init setup_arch_memory(void)
min_high_pfn = PFN_DOWN(high_mem_start);
max_high_pfn = PFN_DOWN(high_mem_start + high_mem_sz);

- /*
- * max_high_pfn should be ok here for both HIGHMEM and HIGHMEM+PAE.
- * For HIGHMEM without PAE max_high_pfn should be less than
- * min_low_pfn to guarantee that these two regions don't overlap.
- * For PAE case highmem is greater than lowmem, so it is natural
- * to use max_high_pfn.
- *
- * In both cases, holes should be handled by pfn_valid().
- */
- max_zone_pfn[ZONE_HIGHMEM] = max_high_pfn;
-
arch_pfn_offset = min(min_low_pfn, min_high_pfn);
kmap_init();
#endif /* CONFIG_HIGHMEM */

+ arch_zone_limits_init(max_zone_pfn);
free_area_init(max_zone_pfn);
}

--
2.51.0