svn commit: r362284 - head/sys/arm64/arm64

[Andrew Turner]

Author: andrew
Date: Wed Jun 17 19:45:05 2020
New Revision: 362284
URL: https://svnweb.freebsd.org/changeset/base/362284

Log:
  Support pmap_extract_and_hold on arm64 stage 2 mappings
  
  Sponsored by:	Innovate UK
  Differential Revision:	https://reviews.freebsd.org/D24469

Modified:
  head/sys/arm64/arm64/pmap.c

Modified: head/sys/arm64/arm64/pmap.c
==============================================================================
--- head/sys/arm64/arm64/pmap.c	Wed Jun 17 18:47:59 2020	(r362283)
+++ head/sys/arm64/arm64/pmap.c	Wed Jun 17 19:45:05 2020	(r362284)
@@ -1228,9 +1228,8 @@ pmap_extract_and_hold(pmap_t pmap, vm_offset_t va, vm_
 	vm_offset_t off;
 	vm_page_t m;
 	int lvl;
+	bool use;
 
-	PMAP_ASSERT_STAGE1(pmap);
-
 	m = NULL;
 	PMAP_LOCK(pmap);
 	pte = pmap_pte(pmap, va, &lvl);
@@ -1244,8 +1243,19 @@ pmap_extract_and_hold(pmap_t pmap, vm_offset_t va, vm_
 		    (lvl < 3 && (tpte & ATTR_DESCR_MASK) == L1_BLOCK),
 		    ("pmap_extract_and_hold: Invalid pte at L%d: %lx", lvl,
 		     tpte & ATTR_DESCR_MASK));
-		if (((tpte & ATTR_S1_AP_RW_BIT) == ATTR_S1_AP(ATTR_S1_AP_RW)) ||
-		    ((prot & VM_PROT_WRITE) == 0)) {
+
+		use = false;
+		if ((prot & VM_PROT_WRITE) == 0)
+			use = true;
+		else if (pmap->pm_stage == PM_STAGE1 &&
+		    (tpte & ATTR_S1_AP_RW_BIT) == ATTR_S1_AP(ATTR_S1_AP_RW))
+			use = true;
+		else if (pmap->pm_stage == PM_STAGE2 &&
+		    ((tpte & ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE)) ==
+		     ATTR_S2_S2AP(ATTR_S2_S2AP_WRITE)))
+			use = true;
+
+		if (use) {
 			switch(lvl) {
 			case 1:
 				off = va & L1_OFFSET;