Index: vm_reserv.c
===================================================================
--- vm_reserv.c
+++ vm_reserv.c
@@ -138,16 +138,46 @@
 }
 
 /*
- * Set a bit in the population map.
+ * Set all bits in the population map range.
  */
 static __inline void
-popmap_set(popmap_t popmap[], int i)
+popmap_range_set(popmap_t popmap[], int start, int count)
 {
+	popmap_t mask;
+	int end, i;
 
-	popmap[i / NBPOPMAP] |= 1UL << (i % NBPOPMAP);
+	end = start + count;
+	for (i = start / NBPOPMAP, mask = -1UL << (start % NBPOPMAP);
+	     i < end / NBPOPMAP; i++, mask = -1UL)
+		popmap[i] |= mask;
+	if (end % NBPOPMAP == 0)
+		return;
+	mask &= ~(-1UL << (end % NBPOPMAP));
+	popmap[i] |= mask;
 }
 
 /*
+ * Are all bits in the population map range clear?
+ */
+static __inline boolean_t
+popmap_range_is_clear(popmap_t popmap[], int start, int count)
+{
+	popmap_t mask;
+	int end, i;
+
+	end = start + count;
+	for (i = start / NBPOPMAP, mask = -1UL << (start % NBPOPMAP);
+	     i < end / NBPOPMAP && (mask & popmap[i]) == 0;
+	     i++, mask = -1UL);
+	if (i < end / NBPOPMAP)
+		return (false);
+	if (end % NBPOPMAP == 0)
+		return (true);
+	mask &= ~(-1UL << (end % NBPOPMAP));
+	return ((mask & popmap[i]) == 0);
+}
+
+/*
  * Is a bit in the population map clear?
  */
 static __inline boolean_t
@@ -295,7 +325,7 @@
 static vm_reserv_t	vm_reserv_from_page(vm_page_t m);
 static boolean_t	vm_reserv_has_pindex(vm_reserv_t rv,
 			    vm_pindex_t pindex);
-static void		vm_reserv_populate(vm_reserv_t rv, int index);
+static void		vm_reserv_populate(vm_reserv_t rv, int index, int num);
 static void		vm_reserv_reclaim(vm_reserv_t rv);
 
 /*
@@ -534,7 +564,7 @@
  * The free page queue must be locked.
  */
 static void
-vm_reserv_populate(vm_reserv_t rv, int index)
+vm_reserv_populate(vm_reserv_t rv, int start, int count)
 {
 
 	vm_reserv_assert_locked(rv);
@@ -542,9 +572,9 @@
 	    __FUNCTION__, rv, rv->object, rv->popcnt, rv->inpartpopq);
 	KASSERT(rv->object != NULL,
 	    ("vm_reserv_populate: reserv %p is free", rv));
-	KASSERT(popmap_is_clear(rv->popmap, index),
-	    ("vm_reserv_populate: reserv %p's popmap[%d] is set", rv,
-	    index));
+	KASSERT(popmap_range_is_clear(rv->popmap, start, count),
+	    ("vm_reserv_populate: reserv %p's popmap[%d..%d) is not clear", rv,
+	     start, start + count));
 	KASSERT(rv->popcnt < VM_LEVEL_0_NPAGES,
 	    ("vm_reserv_populate: reserv %p is already full", rv));
 	KASSERT(rv->pages->psind == 0,
@@ -552,8 +582,8 @@
 	KASSERT(rv->domain < vm_ndomains,
 	    ("vm_reserv_populate: reserv %p's domain is corrupted %d",
 	    rv, rv->domain));
-	popmap_set(rv->popmap, index);
-	rv->popcnt++;
+	popmap_range_set(rv->popmap, start, count);
+	rv->popcnt += count;
 	if ((unsigned)(ticks - rv->lasttick) < PARTPOPSLOP &&
 	    rv->inpartpopq && rv->popcnt != VM_LEVEL_0_NPAGES)
 		return;
@@ -594,7 +624,7 @@
 	vm_paddr_t pa, size;
 	vm_page_t m, msucc;
 	vm_reserv_t rv;
-	int i, index;
+	int index;
 
 	VM_OBJECT_ASSERT_WLOCKED(object);
 	KASSERT(npages != 0, ("vm_reserv_alloc_contig: npages is 0"));
@@ -639,27 +669,21 @@
 	vmd = VM_DOMAIN(domain);
 	vm_reserv_lock(rv);
 	if (rv->object != object)
-		goto out;
-	m = &rv->pages[index];
-	pa = VM_PAGE_TO_PHYS(m);
-	if (pa < low || pa + size > high || (pa & (alignment - 1)) != 0 ||
-	    ((pa ^ (pa + size - 1)) & ~(boundary - 1)) != 0)
-		goto out;
-	/* Handle vm_page_rename(m, new_object, ...). */
-	for (i = 0; i < npages; i++) {
-		if (popmap_is_set(rv->popmap, index + i))
-			goto out;
+		m = NULL;
+	else {
+		m = &rv->pages[index];
+		pa = VM_PAGE_TO_PHYS(m);
+		if (pa >= low && pa + size <= high &&
+		    (pa & (alignment - 1) == 0) &&
+		    ((pa ^ (pa + size - 1)) & ~(boundary - 1)) == 0 &&
+		    popmap_range_is_clear(rv->popmap, index, npages) &&
+		    vm_domain_allocate(vmd, req, npages))
+			vm_reserv_populate(rv, index, npages);
+		else
+			m = NULL;
 	}
-	if (!vm_domain_allocate(vmd, req, npages))
-		goto out;
-	for (i = 0; i < npages; i++)
-		vm_reserv_populate(rv, index + i);
 	vm_reserv_unlock(rv);
 	return (m);
-
-out:
-	vm_reserv_unlock(rv);
-	return (NULL);
 }
 
 /*
@@ -691,7 +715,7 @@
 	vm_pindex_t first, leftcap, rightcap;
 	vm_reserv_t rv;
 	u_long allocpages, maxpages, minpages;
-	int i, index, n;
+	int index, n;
 
 	VM_OBJECT_ASSERT_WLOCKED(object);
 	KASSERT(npages != 0, ("vm_reserv_alloc_contig: npages is 0"));
@@ -833,8 +857,7 @@
 		vm_reserv_lock(rv);
 		vm_reserv_insert(rv, object, first);
 		n = ulmin(VM_LEVEL_0_NPAGES - index, npages);
-		for (i = 0; i < n; i++)
-			vm_reserv_populate(rv, index + i);
+		vm_reserv_populate(rv, index, n);
 		npages -= n;
 		if (m_ret == NULL) {
 			m_ret = &rv->pages[index];
@@ -899,7 +922,7 @@
 	if (vm_domain_allocate(vmd, req, 1) == 0)
 		m = NULL;
 	else
-		vm_reserv_populate(rv, index);
+		vm_reserv_populate(rv, index, 1);
 out:
 	vm_reserv_unlock(rv);
 
@@ -1013,7 +1036,7 @@
 	    ("vm_reserv_alloc_page: reserv %p's pages is corrupted", rv));
 	vm_reserv_insert(rv, object, first);
 	index = VM_RESERV_INDEX(object, pindex);
-	vm_reserv_populate(rv, index);
+	vm_reserv_populate(rv, index, 1);
 	vm_reserv_unlock(rv);
 
 	return (&rv->pages[index]);