[RFC PATCH v2 07/47] hugetlb: add CONFIG_HUGETLB_HIGH_GRANULARITY_MAPPING

[James Houghton]

This adds the Kconfig to enable or disable high-granularity mapping.
Each architecture must explicitly opt-in to it (via
ARCH_WANT_HUGETLB_HIGH_GRANULARITY_MAPPING), but when opted in, HGM will
be enabled by default if HUGETLB_PAGE is enabled.

Signed-off-by: James Houghton <jthoughton@xxxxxxxxxx>
---
 fs/Kconfig | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/fs/Kconfig b/fs/Kconfig
index 2685a4d0d353..ce2567946016 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -267,6 +267,13 @@ config HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON
 	  enable HVO by default. It can be disabled via hugetlb_free_vmemmap=off
 	  (boot command line) or hugetlb_optimize_vmemmap (sysctl).
 
+config ARCH_WANT_HUGETLB_HIGH_GRANULARITY_MAPPING
+	bool
+
+config HUGETLB_HIGH_GRANULARITY_MAPPING
+	def_bool HUGETLB_PAGE
+	depends on ARCH_WANT_HUGETLB_HIGH_GRANULARITY_MAPPING
+
 config MEMFD_CREATE
 	def_bool TMPFS || HUGETLBFS
 
-- 
2.38.0.135.g90850a2211-goog