[RFC 8/9] powerpc/mm: Enable HugeTLB page migration

[Anshuman Khandual]

This change enables HugeTLB page migration for PPC64_BOOK3S systems
for HugeTLB pages implemented at the PMD level. It enables the kernel
configuration option ARCH_ENABLE_HUGEPAGE_MIGRATION which turns on
'hugepage_migration_supported' function which is checked for feature
presence during migration.

Signed-off-by: Anshuman Khandual <khandual at linux.vnet.ibm.com>
---
 arch/powerpc/Kconfig | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index c6920bb..cefc368 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -86,6 +86,10 @@ config GENERIC_HWEIGHT
 config ARCH_HAS_DMA_SET_COHERENT_MASK
         bool
 
+config ARCH_ENABLE_HUGEPAGE_MIGRATION
+	def_bool y
+	depends on PPC_BOOK3S_64 && HUGETLB_PAGE && MIGRATION
+
 config PPC
 	bool
 	default y
-- 
2.1.0