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Diffstat (limited to 'arch/arm64/mm/hugetlbpage.c')
-rw-r--r--arch/arm64/mm/hugetlbpage.c42
1 files changed, 40 insertions, 2 deletions
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 0a52ce46f020..aa421bf4956e 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -19,6 +19,44 @@
#include <asm/tlbflush.h>
#include <asm/pgalloc.h>
+/*
+ * HugeTLB Support Matrix
+ *
+ * ---------------------------------------------------
+ * | Page Size | CONT PTE | PMD | CONT PMD | PUD |
+ * ---------------------------------------------------
+ * | 4K | 64K | 2M | 32M | 1G |
+ * | 16K | 2M | 32M | 1G | |
+ * | 64K | 2M | 512M | 16G | |
+ * ---------------------------------------------------
+ */
+
+/*
+ * Reserve CMA areas for the largest supported gigantic
+ * huge page when requested. Any other smaller gigantic
+ * huge pages could still be served from those areas.
+ */
+#ifdef CONFIG_CMA
+void __init arm64_hugetlb_cma_reserve(void)
+{
+ int order;
+
+#ifdef CONFIG_ARM64_4K_PAGES
+ order = PUD_SHIFT - PAGE_SHIFT;
+#else
+ order = CONT_PMD_SHIFT + PMD_SHIFT - PAGE_SHIFT;
+#endif
+ /*
+ * HugeTLB CMA reservation is required for gigantic
+ * huge pages which could not be allocated via the
+ * page allocator. Just warn if there is any change
+ * breaking this assumption.
+ */
+ WARN_ON(order <= MAX_ORDER);
+ hugetlb_cma_reserve(order);
+}
+#endif /* CONFIG_CMA */
+
#ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION
bool arch_hugetlb_migration_supported(struct hstate *h)
{
@@ -457,9 +495,9 @@ static int __init hugetlbpage_init(void)
#ifdef CONFIG_ARM64_4K_PAGES
hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
#endif
- hugetlb_add_hstate((CONT_PMD_SHIFT + PMD_SHIFT) - PAGE_SHIFT);
+ hugetlb_add_hstate(CONT_PMD_SHIFT - PAGE_SHIFT);
hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT);
- hugetlb_add_hstate((CONT_PTE_SHIFT + PAGE_SHIFT) - PAGE_SHIFT);
+ hugetlb_add_hstate(CONT_PTE_SHIFT - PAGE_SHIFT);
return 0;
}