1 files changed, 103 insertions, 0 deletions
diff --git a/arch/riscv/mm/pgtable.c b/arch/riscv/mm/pgtable.c
new file mode 100644
index 0000000000..fef4e7328e
--- /dev/null
+++ b/arch/riscv/mm/pgtable.c
@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <asm/pgalloc.h>
+#include <linux/gfp.h>
+#include <linux/kernel.h>
+#include <linux/pgtable.h>
+
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot)
+{
+	return 0;
+}
+
+void p4d_clear_huge(p4d_t *p4d)
+{
+}
+
+int pud_set_huge(pud_t *pud, phys_addr_t phys, pgprot_t prot)
+{
+	pud_t new_pud = pfn_pud(__phys_to_pfn(phys), prot);
+
+	set_pud(pud, new_pud);
+	return 1;
+}
+
+int pud_clear_huge(pud_t *pud)
+{
+	if (!pud_leaf(READ_ONCE(*pud)))
+		return 0;
+	pud_clear(pud);
+	return 1;
+}
+
+int pud_free_pmd_page(pud_t *pud, unsigned long addr)
+{
+	pmd_t *pmd = pud_pgtable(*pud);
+	int i;
+
+	pud_clear(pud);
+
+	flush_tlb_kernel_range(addr, addr + PUD_SIZE);
+
+	for (i = 0; i < PTRS_PER_PMD; i++) {
+		if (!pmd_none(pmd[i])) {
+			pte_t *pte = (pte_t *)pmd_page_vaddr(pmd[i]);
+
+			pte_free_kernel(NULL, pte);
+		}
+	}
+
+	pmd_free(NULL, pmd);
+
+	return 1;
+}
+
+int pmd_set_huge(pmd_t *pmd, phys_addr_t phys, pgprot_t prot)
+{
+	pmd_t new_pmd = pfn_pmd(__phys_to_pfn(phys), prot);
+
+	set_pmd(pmd, new_pmd);
+	return 1;
+}
+
+int pmd_clear_huge(pmd_t *pmd)
+{
+	if (!pmd_leaf(READ_ONCE(*pmd)))
+		return 0;
+	pmd_clear(pmd);
+	return 1;
+}
+
+int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
+{
+	pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
+
+	pmd_clear(pmd);
+
+	flush_tlb_kernel_range(addr, addr + PMD_SIZE);
+	pte_free_kernel(NULL, pte);
+	return 1;
+}
+
+#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
+					unsigned long address, pmd_t *pmdp)
+{
+	pmd_t pmd = pmdp_huge_get_and_clear(vma->vm_mm, address, pmdp);
+
+	VM_BUG_ON(address & ~HPAGE_PMD_MASK);
+	VM_BUG_ON(pmd_trans_huge(*pmdp));
+	/*
+	 * When leaf PTE entries (regular pages) are collapsed into a leaf
+	 * PMD entry (huge page), a valid non-leaf PTE is converted into a
+	 * valid leaf PTE at the level 1 page table.  Since the sfence.vma
+	 * forms that specify an address only apply to leaf PTEs, we need a
+	 * global flush here.  collapse_huge_page() assumes these flushes are
+	 * eager, so just do the fence here.
+	 */
+	flush_tlb_mm(vma->vm_mm);
+	return pmd;
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */