Few fixes from NetBSD.

 - make sure that vsunlock doesn't unwire mlocked memory.
 - fix locking in uvm_useracc.
 - Return the error uvm_fault_wire in uvm_vslock (will be used soon).

5 files changed, 90 insertions, 32 deletions

diff --git a/sys/uvm/uvm_extern.h b/sys/uvm/uvm_extern.h
index f6dd3d2aa24..95b93c48569 100644
--- a/sys/uvm/uvm_extern.h
+++ b/sys/uvm/uvm_extern.h
@@ -1,5 +1,5 @@
-/*	$OpenBSD: uvm_extern.h,v 1.10 2001/03/09 14:20:50 art Exp $	*/
-/*	$NetBSD: uvm_extern.h,v 1.28 1999/06/15 23:27:47 thorpej Exp $	*/
+/*	$OpenBSD: uvm_extern.h,v 1.11 2001/05/07 16:08:40 art Exp $	*/
+/*	$NetBSD: uvm_extern.h,v 1.29 1999/06/17 15:47:22 thorpej Exp $	*/
 
 /*
  *
@@ -288,7 +288,7 @@ boolean_t		uvm_kernacc __P((caddr_t, size_t, int));
 __dead void		uvm_scheduler __P((void)) __attribute__((__noreturn__));
 void			uvm_swapin __P((struct proc *));
 boolean_t		uvm_useracc __P((caddr_t, size_t, int));
-void			uvm_vslock __P((struct proc *, caddr_t, size_t,
+int			uvm_vslock __P((struct proc *, caddr_t, size_t,
 			    vm_prot_t));
 void			uvm_vsunlock __P((struct proc *, caddr_t, size_t));
 
diff --git a/sys/uvm/uvm_fault.c b/sys/uvm/uvm_fault.c
index 3d3b75b82bc..50f29232244 100644
--- a/sys/uvm/uvm_fault.c
+++ b/sys/uvm/uvm_fault.c
@@ -1,5 +1,5 @@
-/*	$OpenBSD: uvm_fault.c,v 1.10 2001/03/22 23:36:52 niklas Exp $	*/
-/*	$NetBSD: uvm_fault.c,v 1.35 1999/06/16 18:43:28 thorpej Exp $	*/
+/*	$OpenBSD: uvm_fault.c,v 1.11 2001/05/07 16:08:40 art Exp $	*/
+/*	$NetBSD: uvm_fault.c,v 1.37 1999/06/16 23:02:40 thorpej Exp $	*/
 
 /*
  *
@@ -1707,10 +1707,10 @@ Case2:
 /*
  * uvm_fault_wire: wire down a range of virtual addresses in a map.
  *
- * => map should be locked by caller?   If so how can we call
- *	uvm_fault?   WRONG.
- * => XXXCDC: locking here is all screwed up!!!  start with 
- *	uvm_map_pageable and fix it.
+ * => map may be read-locked by caller, but MUST NOT be write-locked.
+ * => if map is read-locked, any operations which may cause map to
+ *	be write-locked in uvm_fault() must be taken care of by
+ *	the caller.  See uvm_map_pageable().
  */
 
 int
@@ -1761,6 +1761,24 @@ uvm_fault_unwire(map, start, end)
 	vm_map_t map;
 	vaddr_t start, end;
 {
+
+	vm_map_lock_read(map);
+	uvm_fault_unwire_locked(map, start, end);
+	vm_map_unlock_read(map);
+}
+
+/*
+ * uvm_fault_unwire_locked(): the guts of uvm_fault_unwire().
+ *
+ * => map must be at least read-locked.
+ */
+
+void
+uvm_fault_unwire_locked(map, start, end)
+	vm_map_t map;
+	vaddr_t start, end;
+{
+	vm_map_entry_t entry;
 	pmap_t pmap = vm_map_pmap(map);
 	vaddr_t va;
 	paddr_t pa;
@@ -1768,7 +1786,7 @@ uvm_fault_unwire(map, start, end)
 
 #ifdef DIAGNOSTIC
 	if (map->flags & VM_MAP_INTRSAFE)
-		panic("uvm_fault_unwire: intrsafe map");
+		panic("uvm_fault_unwire_locked: intrsafe map");
 #endif
 
 	/*
@@ -1780,15 +1798,47 @@ uvm_fault_unwire(map, start, end)
 
 	uvm_lock_pageq();
 
+	/*
+	 * find the beginning map entry for the region.
+	 */
+#ifdef DIAGNOSTIC
+	if (start < vm_map_min(map) || end > vm_map_max(map))
+		panic("uvm_fault_unwire_locked: address out of range");
+#endif
+	if (uvm_map_lookup_entry(map, start, &entry) == FALSE)
+		panic("uvm_fault_unwire_locked: address not in map");
+
 	for (va = start; va < end ; va += PAGE_SIZE) {
 		pa = pmap_extract(pmap, va);
 
 		/* XXX: assumes PA 0 cannot be in map */
 		if (pa == (paddr_t) 0) {
-			panic("uvm_fault_unwire: unwiring non-wired memory");
+			panic("uvm_fault_unwire_locked: unwiring "
+			    "non-wired memory");
 		}
 
-		pmap_change_wiring(pmap, va, FALSE);  /* tell the pmap */
+		/*
+		 * make sure the current entry is for the address we're
+		 * dealing with.  if not, grab the next entry.
+		 */
+#ifdef DIAGNOSTIC
+		if (va < entry->start)
+			panic("uvm_fault_unwire_locked: hole 1");
+#endif
+		if (va >= entry->end) {
+#ifdef DIAGNOSTIC
+			if (entry->next == &map->header ||
+			    entry->next->start > entry->end)
+				panic("uvm_fault_unwire_locked: hole 2");
+#endif
+			entry = entry->next;
+		}
+
+		/*
+		 * if the entry is no longer wired, tell the pmap.
+		 */
+		if (VM_MAPENT_ISWIRED(entry) == 0)
+			pmap_change_wiring(pmap, va, FALSE);
 
 		pg = PHYS_TO_VM_PAGE(pa);
 		if (pg)
diff --git a/sys/uvm/uvm_fault.h b/sys/uvm/uvm_fault.h
index d77f23f098a..2ab79b5fda5 100644
--- a/sys/uvm/uvm_fault.h
+++ b/sys/uvm/uvm_fault.h
@@ -1,5 +1,5 @@
-/*	$OpenBSD: uvm_fault.h,v 1.6 2001/03/09 05:34:38 smart Exp $	*/
-/*	$NetBSD: uvm_fault.h,v 1.11 1999/06/04 23:38:41 thorpej Exp $	*/
+/*	$OpenBSD: uvm_fault.h,v 1.7 2001/05/07 16:08:40 art Exp $	*/
+/*	$NetBSD: uvm_fault.h,v 1.12 1999/06/16 22:11:23 thorpej Exp $	*/
 
 /*
  *
@@ -84,6 +84,7 @@ static void uvmfault_unlockmaps __P((struct uvm_faultinfo *, boolean_t));
 
 int uvm_fault_wire __P((vm_map_t, vaddr_t, vaddr_t, vm_prot_t));
 void uvm_fault_unwire __P((vm_map_t, vaddr_t, vaddr_t));
+void uvm_fault_unwire_locked __P((vm_map_t, vaddr_t, vaddr_t));
 
 #endif /* _KERNEL */
 
diff --git a/sys/uvm/uvm_glue.c b/sys/uvm/uvm_glue.c
index 800d296d669..bf467bb5a30 100644
--- a/sys/uvm/uvm_glue.c
+++ b/sys/uvm/uvm_glue.c
@@ -1,5 +1,5 @@
-/*	$OpenBSD: uvm_glue.c,v 1.13 2001/05/05 23:25:54 art Exp $	*/
-/*	$NetBSD: uvm_glue.c,v 1.23 1999/05/28 20:49:51 thorpej Exp $	*/
+/*	$OpenBSD: uvm_glue.c,v 1.14 2001/05/07 16:08:40 art Exp $	*/
+/*	$NetBSD: uvm_glue.c,v 1.26 1999/06/17 15:47:22 thorpej Exp $	*/
 
 /* 
  * Copyright (c) 1997 Charles D. Cranor and Washington University.
@@ -155,11 +155,18 @@ uvm_useracc(addr, len, rw)
 	size_t len;
 	int rw;
 {
+	vm_map_t map;
 	boolean_t rv;
 	vm_prot_t prot = rw == B_READ ? VM_PROT_READ : VM_PROT_WRITE;
 
-	rv = uvm_map_checkprot(&curproc->p_vmspace->vm_map,
-			trunc_page((vaddr_t)addr), round_page((vaddr_t)addr+len), prot);
+	/* XXX curproc */
+	map = &curproc->p_vmspace->vm_map;
+
+	vm_map_lock_read(map);
+	rv = uvm_map_checkprot(map, trunc_page((vaddr_t)addr),
+		round_page((vaddr_t)addr+len), prot);
+	vm_map_unlock_read(map);
+
 	return(rv);
 }
 
@@ -210,16 +217,24 @@ uvm_chgkprot(addr, len, rw)
  * - XXXCDC: consider nuking this (or making it a macro?)
  */
 
-void
+int
 uvm_vslock(p, addr, len, access_type)
 	struct proc *p;
 	caddr_t	addr;
 	size_t	len;
 	vm_prot_t access_type;
 {
+	vm_map_t map;
+	vaddr_t start, end;
+	int rv;
+
+	map = &p->p_vmspace->vm_map;
+	start = trunc_page((vaddr_t)addr);
+	end = round_page((vaddr_t)addr + len);
+
+	rv = uvm_fault_wire(map, start, end, access_type);
 
-	uvm_fault_wire(&p->p_vmspace->vm_map, trunc_page((vaddr_t)addr),
-	    round_page((vaddr_t)addr+len), access_type);
+	return (rv);
 }
 
 /*
diff --git a/sys/uvm/uvm_map.c b/sys/uvm/uvm_map.c
index 1ca7c0e883d..266e8462def 100644
--- a/sys/uvm/uvm_map.c
+++ b/sys/uvm/uvm_map.c
@@ -1,5 +1,5 @@
-/*	$OpenBSD: uvm_map.c,v 1.12 2001/05/05 23:25:55 art Exp $	*/
-/*	$NetBSD: uvm_map.c,v 1.56 1999/06/16 19:34:24 thorpej Exp $	*/
+/*	$OpenBSD: uvm_map.c,v 1.13 2001/05/07 16:08:40 art Exp $	*/
+/*	$NetBSD: uvm_map.c,v 1.58 1999/06/17 00:24:10 thorpej Exp $	*/
 
 /* 
  * Copyright (c) 1997 Charles D. Cranor and Washington University.
@@ -293,8 +293,8 @@ uvm_map_entry_unwire(map, entry)
 	vm_map_entry_t entry;
 {
 
-	uvm_fault_unwire(map, entry->start, entry->end);
 	entry->wired_count = 0;
+	uvm_fault_unwire_locked(map, entry->start, entry->end);
 }
 
 /*
@@ -2043,10 +2043,6 @@ uvm_map_pageable(map, start, end, new_pageable)
 		 * POSIX 1003.1b - a single munlock call unlocks a region,
 		 * regardless of the number of mlock calls made on that
 		 * region.
-		 *
-		 * Note, uvm_fault_unwire() (called via uvm_map_entry_unwire())
-		 * does not lock the map, so we don't have to do anything
-		 * special regarding locking here.
 		 */
 		entry = start_entry;
 		while ((entry != &map->header) && (entry->start < end)) {
@@ -2229,10 +2225,6 @@ uvm_map_pageable_all(map, flags, limit)
 		/*
 		 * POSIX 1003.1b -- munlockall unlocks all regions,
 		 * regardless of how many times mlockall has been called.
-		 *
-		 * Note, uvm_fault_unwire() (called via uvm_map_entry_unwire())
-		 * does not lock the map, so we don't have to do anything
-		 * special regarding locking here.
 		 */
 		for (entry = map->header.next; entry != &map->header;
 		     entry = entry->next) {