From 639d0e496b1f28b3978824d10c8ae67439aa6027 Mon Sep 17 00:00:00 2001
From: "TOIDA,Suguru" <fj1520as@aa.jp.fujitsu.com>
Date: Fri, 30 Nov 2018 09:18:01 +0900
Subject: [PATCH] ContiguousPTE[3/12] modify move_pte_range

Change-Id: I20878c97bea768d1f09ab0580d744a58c070be2c
---
 arch/arm64/kernel/memory.c | 40 +++++++++++++++++++++++++++++++++++++-
 1 file changed, 39 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/memory.c b/arch/arm64/kernel/memory.c
index bbc8c0a6..054a9397 100644
--- a/arch/arm64/kernel/memory.c
+++ b/arch/arm64/kernel/memory.c
@@ -2601,7 +2601,7 @@ static int move_one_page(void *arg0, page_table_t pt, pte_t *ptep,
 {
 	int error;
 	struct move_args *args = arg0;
-	const size_t pgsize = (size_t)1 << pgshift;
+	size_t pgsize = (size_t)1 << pgshift;
 	uintptr_t dest;
 	pte_t apte;
 	uintptr_t phys;
@@ -2621,6 +2621,20 @@ static int move_one_page(void *arg0, page_table_t pt, pte_t *ptep,
 	apte = PTE_NULL;
 	pte_xchg(ptep, &apte);
 
+	// check attributes before clearing to PTE_NULL
+	if (pte_is_contiguous(&apte)) {
+		// check if ptep is an entry of contiguous pte head
+		if (page_is_contiguous_head(ptep, pgsize)) {
+			int level = pgsize_to_tbllv(pgsize);
+
+			pgsize = tbllv_to_contpgsize(level);
+			pgshift = tbllv_to_contpgshift(level);
+		} else {
+			error = 0;
+			goto out;
+		}
+	}
+
 	phys = apte & PT_PHYSMASK;
 	attr = apte & ~PT_PHYSMASK;
 
@@ -2645,6 +2659,8 @@ int move_pte_range(page_table_t pt, struct process_vm *vm,
 {
 	int error;
 	struct move_args args;
+	pte_t *ptep;
+	size_t pgsize;
 
 	dkprintf("move_pte_range(%p,%p,%p,%#lx)\n", pt, src, dest, size);
 	args.src = (uintptr_t)src;
@@ -2652,6 +2668,28 @@ int move_pte_range(page_table_t pt, struct process_vm *vm,
 	args.vm = vm;
 	args.range = range;
 
+	ptep = ihk_mc_pt_lookup_pte(pt, src, 0, NULL, &pgsize, NULL);
+	if (ptep && pte_is_contiguous(ptep)) {
+		if (!page_is_contiguous_head(ptep, pgsize)) {
+			// start pte is not contiguous head
+			error = split_contiguous_pages(ptep, pgsize);
+			if (error) {
+				goto out;
+			}
+		}
+	}
+
+	ptep = ihk_mc_pt_lookup_pte(pt, src + size - 1, 0, NULL, &pgsize, NULL);
+	if (ptep && pte_is_contiguous(ptep)) {
+		if (!page_is_contiguous_tail(ptep, pgsize)) {
+			// end pte is not contiguous tail
+			error = split_contiguous_pages(ptep, pgsize);
+			if (error) {
+				goto out;
+			}
+		}
+	}
+
 	error = visit_pte_range(pt, src, src+size, 0, VPTEF_SKIP_NULL,
 			&move_one_page, &args);
 	flush_tlb();	/* XXX: TLB flush */