Bring in some new UVM code from NetBSD (not current).

 - Introduce a new type of map that are interrupt safe and never allow faults
   in them. mb_map and kmem_map are made intrsafe.
 - Add "access protection" to uvm_vslock (to be passed down to uvm_fault and
   later to pmap_enter).
 - madvise(2) now works.
 - various cleanups.

1 files changed, 37 insertions, 8 deletions

diff --git a/sys/uvm/uvm_fault.c b/sys/uvm/uvm_fault.c
index d05c5c30282..b4002aceb87 100644
--- a/sys/uvm/uvm_fault.c
+++ b/sys/uvm/uvm_fault.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: uvm_fault.c,v 1.28 1999/04/11 04:04:11 chs Exp $	*/
+/*	$NetBSD: uvm_fault.c,v 1.33 1999/06/04 23:38:41 thorpej Exp $	*/
 
 /*
  *
@@ -587,6 +587,19 @@ uvm_fault(orig_map, vaddr, fault_type, access_type)
 		narrow = FALSE;		/* normal fault */
 
 	/*
+	 * before we do anything else, if this is a fault on a kernel
+	 * address, check to see if the address is managed by an
+	 * interrupt-safe map.  If it is, we fail immediately.  Intrsafe
+	 * maps are never pageable, and this approach avoids an evil
+	 * locking mess.
+	 */
+	if (orig_map == kernel_map && uvmfault_check_intrsafe(&ufi)) {
+		UVMHIST_LOG(maphist, "<- VA 0x%lx in intrsafe map %p",
+		    ufi.orig_rvaddr, ufi.map, 0, 0);
+		return (KERN_FAILURE);
+	}
+
+	/*
 	 * "goto ReFault" means restart the page fault from ground zero.
 	 */
 ReFault:
@@ -614,6 +627,17 @@ ReFault:
 	}
 
 	/*
+	 * if the map is not a pageable map, a page fault always fails.
+	 */
+
+	if ((ufi.map->flags & VM_MAP_PAGEABLE) == 0) {
+		UVMHIST_LOG(maphist,
+		    "<- map %p not pageable", ufi.map, 0, 0, 0);
+		uvmfault_unlockmaps(&ufi, FALSE);
+		return (KERN_FAILURE);
+	}
+
+	/*
 	 * "enter_prot" is the protection we want to enter the page in at.
 	 * for certain pages (e.g. copy-on-write pages) this protection can
 	 * be more strict than ufi.entry->protection.  "wired" means either
@@ -1689,9 +1713,10 @@ Case2:
  */
 
 int
-uvm_fault_wire(map, start, end)
+uvm_fault_wire(map, start, end, access_type)
 	vm_map_t map;
 	vaddr_t start, end;
+	vm_prot_t access_type;
 {
 	vaddr_t va;
 	pmap_t  pmap;
@@ -1713,10 +1738,10 @@ uvm_fault_wire(map, start, end)
 	 */
 
 	for (va = start ; va < end ; va += PAGE_SIZE) {
-		rv = uvm_fault(map, va, VM_FAULT_WIRE, VM_PROT_NONE);
+		rv = uvm_fault(map, va, VM_FAULT_WIRE, access_type);
 		if (rv) {
 			if (va != start) {
-				uvm_fault_unwire(map->pmap, start, va);
+				uvm_fault_unwire(map, start, va);
 			}
 			return (rv);
 		}
@@ -1727,19 +1752,23 @@ uvm_fault_wire(map, start, end)
 
 /*
  * uvm_fault_unwire(): unwire range of virtual space.
- *
- * => caller holds reference to pmap (via its map)
  */
 
 void
-uvm_fault_unwire(pmap, start, end)
-	struct pmap *pmap;
+uvm_fault_unwire(map, start, end)
+	vm_map_t map;
 	vaddr_t start, end;
 {
+	pmap_t pmap = vm_map_pmap(map);
 	vaddr_t va;
 	paddr_t pa;
 	struct vm_page *pg;
 
+#ifdef DIAGNOSTIC
+	if (map->flags & VM_MAP_INTRSAFE)
+		panic("uvm_fault_unwire: intrsafe map");
+#endif
+
 	/*
 	 * we assume that the area we are unwiring has actually been wired
 	 * in the first place.   this means that we should be able to extract