[PATCH] mm/memblock: export max_pfn for kernel modules

From: Miles Chen <miles.chen@mediatek.com>
To: Mike Rapoport <rppt@linux.ibm.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Matthias Brugger <matthias.bgg@gmail.com>
Cc: <linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-mediatek@lists.infradead.org>, <wsd_upstream@mediatek.com>,
	Miles Chen <miles.chen@mediatek.com>
Subject: [PATCH] mm/memblock: export max_pfn for kernel modules
Date: Thu, 4 Jun 2020 00:11:32 +0800	[thread overview]
Message-ID: <20200603161132.2441-1-miles.chen@mediatek.com> (raw)

max_pfn is uesd to get the highest pfn in the system. Drivers like
drivers/iommu/mtk_iommu.c checks max_pfn to see if it should enable
its "4GB mode".

This patch exports the max_pfn symbol, so we can build the driver as
a kernel module.

Signed-off-by: Miles Chen <miles.chen@mediatek.com>
---
 mm/memblock.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mm/memblock.c b/mm/memblock.c
index c79ba6f9920c..3b2b21ecebb6 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -99,6 +99,7 @@ EXPORT_SYMBOL(contig_page_data);
 unsigned long max_low_pfn;
 unsigned long min_low_pfn;
 unsigned long max_pfn;
+EXPORT_SYMBOL(max_pfn);
 unsigned long long max_possible_pfn;
 
 static struct memblock_region memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS] __initdata_memblock;
-- 
2.18.0
