- Move the PG_UNMANAGED flag from m->flags to m->oflags, renaming the flag

  to VPO_UNMANAGED (and also making the flag protected by the vm object
  lock, instead of vm page queue lock).
- Mark the fake pages with both PG_FICTITIOUS (as it is now) and
  VPO_UNMANAGED. As a consequence, pmap code now can use use just
  VPO_UNMANAGED to decide whether the page is unmanaged.

Reviewed by:	alc
Tested by:	pho (x86, previous version), marius (sparc64),
    marcel (arm, ia64, powerpc), ray (mips)
Sponsored by:	The FreeBSD Foundation
Approved by:	re (bz)

4 files changed, 37 insertions, 33 deletions

diff --git a/sys/vm/vm_kern.c b/sys/vm/vm_kern.c
index 23884af..24c2448 100644
--- a/sys/vm/vm_kern.c
+++ b/sys/vm/vm_kern.c
@@ -210,7 +210,7 @@ kmem_alloc(map, size)
 		mem = vm_page_grab(kernel_object, OFF_TO_IDX(offset + i),
 		    VM_ALLOC_NOBUSY | VM_ALLOC_ZERO | VM_ALLOC_RETRY);
 		mem->valid = VM_PAGE_BITS_ALL;
-		KASSERT((mem->flags & PG_UNMANAGED) != 0,
+		KASSERT((mem->oflags & VPO_UNMANAGED) != 0,
 		    ("kmem_alloc: page %p is managed", mem));
 	}
 	VM_OBJECT_UNLOCK(kernel_object);
@@ -428,7 +428,7 @@ retry:
 		if (flags & M_ZERO && (m->flags & PG_ZERO) == 0)
 			pmap_zero_page(m);
 		m->valid = VM_PAGE_BITS_ALL;
-		KASSERT((m->flags & PG_UNMANAGED) != 0,
+		KASSERT((m->oflags & VPO_UNMANAGED) != 0,
 		    ("kmem_malloc: page %p is managed", m));
 	}
 	VM_OBJECT_UNLOCK(kmem_object);
diff --git a/sys/vm/vm_object.c b/sys/vm/vm_object.c
index b5788f5..602d99e 100644
--- a/sys/vm/vm_object.c
+++ b/sys/vm/vm_object.c
@@ -1087,7 +1087,9 @@ shadowlookup:
 			vm_page_unlock(m);
 			goto unlock_tobject;
 		}
-		KASSERT((m->flags & (PG_FICTITIOUS | PG_UNMANAGED)) == 0,
+		KASSERT((m->flags & PG_FICTITIOUS) == 0,
+		    ("vm_object_madvise: page %p is fictitious", m));
+		KASSERT((m->oflags & VPO_UNMANAGED) == 0,
 		    ("vm_object_madvise: page %p is not managed", m));
 		if ((m->oflags & VPO_BUSY) || m->busy) {
 			if (advise == MADV_WILLNEED) {
diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c
index 8e0c8bb..6d55892 100644
--- a/sys/vm/vm_page.c
+++ b/sys/vm/vm_page.c
@@ -483,8 +483,8 @@ vm_page_flag_set(vm_page_t m, unsigned short bits)
 	 * VPO_BUSY.  Currently, this flag is only set by pmap_enter().
 	 */
 	KASSERT((bits & PG_WRITEABLE) == 0 ||
-	    ((m->flags & (PG_UNMANAGED | PG_FICTITIOUS)) == 0 &&
-	    (m->oflags & VPO_BUSY) != 0), ("PG_WRITEABLE and !VPO_BUSY"));
+	    (m->oflags & (VPO_UNMANAGED | VPO_BUSY)) == VPO_BUSY,
+	    ("PG_WRITEABLE and !VPO_BUSY"));
 	m->flags |= bits;
 } 
 
@@ -636,7 +636,7 @@ vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr)
 	/* Fictitious pages don't use "segind". */
 	m->flags = PG_FICTITIOUS;
 	/* Fictitious pages don't use "order" or "pool". */
-	m->oflags = VPO_BUSY;
+	m->oflags = VPO_BUSY | VPO_UNMANAGED;
 	m->wire_count = 1;
 	pmap_page_set_memattr(m, memattr);
 	return (m);
@@ -896,7 +896,7 @@ vm_page_remove(vm_page_t m)
 	vm_object_t object;
 	vm_page_t root;
 
-	if ((m->flags & PG_UNMANAGED) == 0)
+	if ((m->oflags & VPO_UNMANAGED) == 0)
 		vm_page_lock_assert(m, MA_OWNED);
 	if ((object = m->object) == NULL)
 		return;
@@ -1388,14 +1388,14 @@ vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req)
 		if (req & VM_ALLOC_ZERO)
 			flags = PG_ZERO;
 	}
-	if (object == NULL || object->type == OBJT_PHYS)
-		flags |= PG_UNMANAGED;
 	m->flags = flags;
 	mtx_unlock(&vm_page_queue_free_mtx);
-	if (req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ))
-		m->oflags = 0;
+	if (object == NULL || object->type == OBJT_PHYS)
+		m->oflags = VPO_UNMANAGED;
 	else
-		m->oflags = VPO_BUSY;
+		m->oflags = 0;
+	if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ)) == 0)
+		m->oflags |= VPO_BUSY;
 	if (req & VM_ALLOC_WIRED) {
 		/*
 		 * The page lock is not required for wiring a page until that
@@ -1479,8 +1479,8 @@ vm_page_alloc_init(vm_page_t m)
 	if (m->flags & PG_ZERO)
 		vm_page_zero_count--;
 	/* Don't clear the PG_ZERO flag; we'll need it later. */
-	m->flags = PG_UNMANAGED | (m->flags & PG_ZERO);
-	m->oflags = 0;
+	m->flags &= PG_ZERO;
+	m->oflags = VPO_UNMANAGED;
 	/* Unmanaged pages don't use "act_count". */
 	return (drop);
 }
@@ -1670,7 +1670,7 @@ vm_page_activate(vm_page_t m)
 	vm_page_lock_assert(m, MA_OWNED);
 	VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED);
 	if ((queue = m->queue) != PQ_ACTIVE) {
-		if (m->wire_count == 0 && (m->flags & PG_UNMANAGED) == 0) {
+		if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) {
 			if (m->act_count < ACT_INIT)
 				m->act_count = ACT_INIT;
 			vm_page_lock_queues();
@@ -1736,7 +1736,7 @@ void
 vm_page_free_toq(vm_page_t m)
 {
 
-	if ((m->flags & PG_UNMANAGED) == 0) {
+	if ((m->oflags & VPO_UNMANAGED) == 0) {
 		vm_page_lock_assert(m, MA_OWNED);
 		KASSERT(!pmap_page_is_mapped(m),
 		    ("vm_page_free_toq: freeing mapped page %p", m));
@@ -1754,7 +1754,7 @@ vm_page_free_toq(vm_page_t m)
 	 * callback routine until after we've put the page on the
 	 * appropriate free queue.
 	 */
-	if ((m->flags & PG_UNMANAGED) == 0)
+	if ((m->oflags & VPO_UNMANAGED) == 0)
 		vm_pageq_remove(m);
 	vm_page_remove(m);
 
@@ -1834,7 +1834,7 @@ vm_page_wire(vm_page_t m)
 		return;
 	}
 	if (m->wire_count == 0) {
-		if ((m->flags & PG_UNMANAGED) == 0)
+		if ((m->oflags & VPO_UNMANAGED) == 0)
 			vm_pageq_remove(m);
 		atomic_add_int(&cnt.v_wire_count, 1);
 	}
@@ -1862,7 +1862,7 @@ void
 vm_page_unwire(vm_page_t m, int activate)
 {
 
-	if ((m->flags & PG_UNMANAGED) == 0)
+	if ((m->oflags & VPO_UNMANAGED) == 0)
 		vm_page_lock_assert(m, MA_OWNED);
 	if ((m->flags & PG_FICTITIOUS) != 0) {
 		KASSERT(m->wire_count == 1,
@@ -1873,7 +1873,7 @@ vm_page_unwire(vm_page_t m, int activate)
 		m->wire_count--;
 		if (m->wire_count == 0) {
 			atomic_subtract_int(&cnt.v_wire_count, 1);
-			if ((m->flags & PG_UNMANAGED) != 0 ||
+			if ((m->oflags & VPO_UNMANAGED) != 0 ||
 			    m->object == NULL)
 				return;
 			vm_page_lock_queues();
@@ -1921,7 +1921,7 @@ _vm_page_deactivate(vm_page_t m, int athead)
 	 */
 	if ((queue = m->queue) == PQ_INACTIVE)
 		return;
-	if (m->wire_count == 0 && (m->flags & PG_UNMANAGED) == 0) {
+	if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) {
 		vm_page_lock_queues();
 		vm_page_flag_clear(m, PG_WINATCFLS);
 		if (queue != PQ_NONE)
@@ -1962,7 +1962,7 @@ vm_page_try_to_cache(vm_page_t m)
 	vm_page_lock_assert(m, MA_OWNED);
 	VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED);
 	if (m->dirty || m->hold_count || m->busy || m->wire_count ||
-	    (m->oflags & VPO_BUSY) || (m->flags & PG_UNMANAGED))
+	    (m->oflags & (VPO_BUSY | VPO_UNMANAGED)) != 0)
 		return (0);
 	pmap_remove_all(m);
 	if (m->dirty)
@@ -1985,7 +1985,7 @@ vm_page_try_to_free(vm_page_t m)
 	if (m->object != NULL)
 		VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED);
 	if (m->dirty || m->hold_count || m->busy || m->wire_count ||
-	    (m->oflags & VPO_BUSY) || (m->flags & PG_UNMANAGED))
+	    (m->oflags & (VPO_BUSY | VPO_UNMANAGED)) != 0)
 		return (0);
 	pmap_remove_all(m);
 	if (m->dirty)
@@ -2010,7 +2010,7 @@ vm_page_cache(vm_page_t m)
 	vm_page_lock_assert(m, MA_OWNED);
 	object = m->object;
 	VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
-	if ((m->flags & PG_UNMANAGED) || (m->oflags & VPO_BUSY) || m->busy ||
+	if ((m->oflags & (VPO_UNMANAGED | VPO_BUSY)) || m->busy ||
 	    m->hold_count || m->wire_count)
 		panic("vm_page_cache: attempting to cache busy page");
 	pmap_remove_all(m);
@@ -2657,7 +2657,8 @@ vm_page_cowsetup(vm_page_t m)
 {
 
 	vm_page_lock_assert(m, MA_OWNED);
-	if ((m->flags & (PG_FICTITIOUS | PG_UNMANAGED)) != 0 ||
+	if ((m->flags & PG_FICTITIOUS) != 0 ||
+	    (m->oflags & VPO_UNMANAGED) != 0 ||
 	    m->cow == USHRT_MAX - 1 || !VM_OBJECT_TRYLOCK(m->object))
 		return (EBUSY);
 	m->cow++;
diff --git a/sys/vm/vm_page.h b/sys/vm/vm_page.h
index e852313..1dda1e2 100644
--- a/sys/vm/vm_page.h
+++ b/sys/vm/vm_page.h
@@ -157,9 +157,18 @@ struct vm_page {
  *
  * Access to these page flags is synchronized by the lock on the object
  * containing the page (O).
+ *
+ * Note: VPO_UNMANAGED (used by OBJT_DEVICE, OBJT_PHYS and OBJT_SG)
+ * 	 indicates that the page is not under PV management but
+ * 	 otherwise should be treated as a normal page.  Pages not
+ * 	 under PV management cannot be paged out via the
+ * 	 object/vm_page_t because there is no knowledge of their pte
+ * 	 mappings, and such pages are also not on any PQ queue.
+ *
  */
 #define	VPO_BUSY	0x0001	/* page is in transit */
 #define	VPO_WANTED	0x0002	/* someone is waiting for page */
+#define	VPO_UNMANAGED	0x0004		/* No PV management for page */
 #define	VPO_SWAPINPROG	0x0200	/* swap I/O in progress on page */
 #define	VPO_NOSYNC	0x0400	/* do not collect for syncer */
 
@@ -216,13 +225,6 @@ extern struct vpglocks pa_lock[];
 /*
  * These are the flags defined for vm_page.
  *
- * Note: PG_UNMANAGED (used by OBJT_PHYS) indicates that the page is
- * 	 not under PV management but otherwise should be treated as a
- *	 normal page.  Pages not under PV management cannot be paged out
- *	 via the object/vm_page_t because there is no knowledge of their
- *	 pte mappings, nor can they be removed from their objects via 
- *	 the object, and such pages are also not on any PQ queue.
- *
  * PG_REFERENCED may be cleared only if the object containing the page is
  * locked.
  *
@@ -236,7 +238,6 @@ extern struct vpglocks pa_lock[];
 #define	PG_WRITEABLE	0x0010		/* page is mapped writeable */
 #define	PG_ZERO		0x0040		/* page is zeroed */
 #define PG_REFERENCED	0x0080		/* page has been referenced */
-#define PG_UNMANAGED	0x0800		/* No PV management for page */
 #define PG_MARKER	0x1000		/* special queue marker page */
 #define	PG_SLAB		0x2000		/* object pointer is actually a slab */