Re: [PATCH v2 14/28] powerpc: introduce arch_zone_limits_init()
From: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Date: 2026-01-07 04:58:22
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Mike Rapoport [off-list ref] writes:
quoted hunk ↗ jump to hunk
From: "Mike Rapoport (Microsoft)" <rppt@kernel.org> 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> --- arch/powerpc/mm/mem.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-)diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index 3ddbfdbfa941..32c496bfab4f 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c@@ -221,13 +221,23 @@ static int __init mark_nonram_nosave(void) * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by * ZONE_DMA. */ -static unsigned long max_zone_pfns[MAX_NR_ZONES]; +void __init arch_zone_limits_init(unsigned long *max_zone_pfns) +{ +#ifdef CONFIG_ZONE_DMA + max_zone_pfns[ZONE_DMA] = min(zone_dma_limit, max_low_pfn - 1) + 1;
Hi Mike,
This doesn't look correct. Isn't the zone_dma_limit value in bytes actually?
Shouldn't it be -
max_zone_pfns[ZONE_DMA] = min((zone_dma_limit >> PAGE_SHIFT) + 1, max_low_pfn);
-ritesh
quoted hunk ↗ jump to hunk
+#endif + max_zone_pfns[ZONE_NORMAL] = max_low_pfn; +#ifdef CONFIG_HIGHMEM + max_zone_pfns[ZONE_HIGHMEM] = max_pfn; +#endif +} /* * paging_init() sets up the page tables - in fact we've already done this. */ void __init paging_init(void) { + unsigned long max_zone_pfns[MAX_NR_ZONES]; unsigned long long total_ram = memblock_phys_mem_size(); phys_addr_t top_of_ram = memblock_end_of_DRAM(); int zone_dma_bits;@@ -259,15 +269,7 @@ void __init paging_init(void) zone_dma_limit = DMA_BIT_MASK(zone_dma_bits); -#ifdef CONFIG_ZONE_DMA - max_zone_pfns[ZONE_DMA] = min(max_low_pfn, - 1UL << (zone_dma_bits - PAGE_SHIFT)); -#endif - max_zone_pfns[ZONE_NORMAL] = max_low_pfn; -#ifdef CONFIG_HIGHMEM - max_zone_pfns[ZONE_HIGHMEM] = max_pfn; -#endif - + arch_zone_limits_init(max_zone_pfns); free_area_init(max_zone_pfns); mark_nonram_nosave();-- 2.51.0