1 files changed, 135 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/hugetlb.h b/arch/powerpc/include/asm/book3s/64/hugetlb.h
new file mode 100644
index 0000000000..aa1c67c8bf
--- /dev/null
+++ b/arch/powerpc/include/asm/book3s/64/hugetlb.h
@@ -0,0 +1,135 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_POWERPC_BOOK3S_64_HUGETLB_H
+#define _ASM_POWERPC_BOOK3S_64_HUGETLB_H
+
+#include <asm/firmware.h>
+
+/*
+ * For radix we want generic code to handle hugetlb. But then if we want
+ * both hash and radix to be enabled together we need to workaround the
+ * limitations.
+ */
+void radix__flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr);
+void radix__local_flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr);
+
+extern void radix__huge_ptep_modify_prot_commit(struct vm_area_struct *vma,
+						unsigned long addr, pte_t *ptep,
+						pte_t old_pte, pte_t pte);
+
+static inline int hstate_get_psize(struct hstate *hstate)
+{
+	unsigned long shift;
+
+	shift = huge_page_shift(hstate);
+	if (shift == mmu_psize_defs[MMU_PAGE_2M].shift)
+		return MMU_PAGE_2M;
+	else if (shift == mmu_psize_defs[MMU_PAGE_1G].shift)
+		return MMU_PAGE_1G;
+	else if (shift == mmu_psize_defs[MMU_PAGE_16M].shift)
+		return MMU_PAGE_16M;
+	else if (shift == mmu_psize_defs[MMU_PAGE_16G].shift)
+		return MMU_PAGE_16G;
+	else {
+		WARN(1, "Wrong huge page shift\n");
+		return mmu_virtual_psize;
+	}
+}
+
+#define __HAVE_ARCH_GIGANTIC_PAGE_RUNTIME_SUPPORTED
+static inline bool gigantic_page_runtime_supported(void)
+{
+	/*
+	 * We used gigantic page reservation with hypervisor assist in some case.
+	 * We cannot use runtime allocation of gigantic pages in those platforms
+	 * This is hash translation mode LPARs.
+	 */
+	if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
+		return false;
+
+	return true;
+}
+
+/* hugepd entry valid bit */
+#define HUGEPD_VAL_BITS		(0x8000000000000000UL)
+
+#define huge_ptep_modify_prot_start huge_ptep_modify_prot_start
+extern pte_t huge_ptep_modify_prot_start(struct vm_area_struct *vma,
+					 unsigned long addr, pte_t *ptep);
+
+#define huge_ptep_modify_prot_commit huge_ptep_modify_prot_commit
+extern void huge_ptep_modify_prot_commit(struct vm_area_struct *vma,
+					 unsigned long addr, pte_t *ptep,
+					 pte_t old_pte, pte_t new_pte);
+/*
+ * This should work for other subarchs too. But right now we use the
+ * new format only for 64bit book3s
+ */
+static inline pte_t *hugepd_page(hugepd_t hpd)
+{
+	BUG_ON(!hugepd_ok(hpd));
+	/*
+	 * We have only four bits to encode, MMU page size
+	 */
+	BUILD_BUG_ON((MMU_PAGE_COUNT - 1) > 0xf);
+	return __va(hpd_val(hpd) & HUGEPD_ADDR_MASK);
+}
+
+static inline unsigned int hugepd_mmu_psize(hugepd_t hpd)
+{
+	return (hpd_val(hpd) & HUGEPD_SHIFT_MASK) >> 2;
+}
+
+static inline unsigned int hugepd_shift(hugepd_t hpd)
+{
+	return mmu_psize_to_shift(hugepd_mmu_psize(hpd));
+}
+static inline void flush_hugetlb_page(struct vm_area_struct *vma,
+				      unsigned long vmaddr)
+{
+	if (radix_enabled())
+		return radix__flush_hugetlb_page(vma, vmaddr);
+}
+
+static inline pte_t *hugepte_offset(hugepd_t hpd, unsigned long addr,
+				    unsigned int pdshift)
+{
+	unsigned long idx = (addr & ((1UL << pdshift) - 1)) >> hugepd_shift(hpd);
+
+	return hugepd_page(hpd) + idx;
+}
+
+static inline void hugepd_populate(hugepd_t *hpdp, pte_t *new, unsigned int pshift)
+{
+	*hpdp = __hugepd(__pa(new) | HUGEPD_VAL_BITS | (shift_to_mmu_psize(pshift) << 2));
+}
+
+void flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr);
+
+static inline int check_and_get_huge_psize(int shift)
+{
+	int mmu_psize;
+
+	if (shift > SLICE_HIGH_SHIFT)
+		return -EINVAL;
+
+	mmu_psize = shift_to_mmu_psize(shift);
+
+	/*
+	 * We need to make sure that for different page sizes reported by
+	 * firmware we only add hugetlb support for page sizes that can be
+	 * supported by linux page table layout.
+	 * For now we have
+	 * Radix: 2M and 1G
+	 * Hash: 16M and 16G
+	 */
+	if (radix_enabled()) {
+		if (mmu_psize != MMU_PAGE_2M && mmu_psize != MMU_PAGE_1G)
+			return -EINVAL;
+	} else {
+		if (mmu_psize != MMU_PAGE_16M && mmu_psize != MMU_PAGE_16G)
+			return -EINVAL;
+	}
+	return mmu_psize;
+}
+
+#endif