arm64: Re-enable support for contiguous hugepages

also known as -

Revert "Revert "Revert "commit 66b3923a1a0f ("arm64: hugetlb: add
support for PTE contiguous bit")"""

Now that our hugetlb implementation is compliant with the
break-before-make requirements of the architecture and we have addressed
some of the issues in core code required for properly dealing with
hardware poisoning of contiguous hugepages let's re-enable support for
contiguous hugepages.

This reverts commit 6ae979ab39a368c18ceb0424bf824d172d6ab56f.

Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 76915b7..3ceb4f2 100644 (file)
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -408,6 +408,10 @@ static __init int setup_hugepagesz(char *opt)
                hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT);
        } else if (ps == PUD_SIZE) {
                hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
+       } else if (ps == (PAGE_SIZE * CONT_PTES)) {
+               hugetlb_add_hstate(CONT_PTE_SHIFT);
+       } else if (ps == (PMD_SIZE * CONT_PMDS)) {
+               hugetlb_add_hstate((PMD_SHIFT + CONT_PMD_SHIFT) - PAGE_SHIFT);
        } else {
                hugetlb_bad_size();
                pr_err("hugepagesz: Unsupported page size %lu K\n", ps >> 10);
@@ -416,3 +420,13 @@ static __init int setup_hugepagesz(char *opt)
        return 1;
 }
 __setup("hugepagesz=", setup_hugepagesz);
+
+#ifdef CONFIG_ARM64_64K_PAGES
+static __init int add_default_hugepagesz(void)
+{
+       if (size_to_hstate(CONT_PTES * PAGE_SIZE) == NULL)
+               hugetlb_add_hstate(CONT_PTE_SHIFT);
+       return 0;
+}
+arch_initcall(add_default_hugepagesz);
+#endif