Background: pmap_object_init_pt() premaps the pages of a object in

order to avoid the overhead of later page faults.  In general, it
implements two cases: one for vnode-backed objects and one for
device-backed objects.  Only the device-backed case is really
machine-dependent, belonging in the pmap.

This commit moves the vnode-backed case into the (relatively) new
function vm_map_pmap_enter().  On amd64 and i386, this commit only
amounts to code rearrangement.  On alpha and ia64, the new machine
independent (MI) implementation of the vnode case is smaller and more
efficient than their pmap-based implementations.  (The MI
implementation takes advantage of the fact that objects in -CURRENT
are ordered collections of pages.)  On sparc64, pmap_object_init_pt()
hadn't (yet) been implemented.

1 files changed, 14 insertions, 82 deletions

diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c
index 875f783..83aae58 100644
--- a/sys/amd64/amd64/pmap.c
+++ b/sys/amd64/amd64/pmap.c
@@ -2057,31 +2057,22 @@ pmap_kenter_temporary(vm_offset_t pa, int i)
 	return ((void *)crashdumpmap);
 }
 
-#define MAX_INIT_PT (96)
 /*
- * pmap_object_init_pt preloads the ptes for a given object
- * into the specified pmap.  This eliminates the blast of soft
- * faults on process startup and immediately after an mmap.
+ * This code maps large physical mmap regions into the
+ * processor address space.  Note that some shortcuts
+ * are taken, but the code works.
  */
 void
 pmap_object_init_pt(pmap_t pmap, vm_offset_t addr,
 		    vm_object_t object, vm_pindex_t pindex,
-		    vm_size_t size, int limit)
+		    vm_size_t size)
 {
-	vm_pindex_t tmpidx;
-	int psize;
-	vm_page_t p, mpte;
+	vm_page_t p;
 
-	if (pmap == NULL || object == NULL)
-		return;
-	VM_OBJECT_LOCK(object);
-	/*
-	 * This code maps large physical mmap regions into the
-	 * processor address space.  Note that some shortcuts
-	 * are taken, but the code works.
-	 */
-	if ((object->type == OBJT_DEVICE) &&
-	    ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) {
+	VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
+	KASSERT(object->type == OBJT_DEVICE,
+	    ("pmap_object_init_pt: non-device object"));
+	if (((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) {
 		int i;
 		vm_page_t m[1];
 		int npdes;
@@ -2089,7 +2080,7 @@ pmap_object_init_pt(pmap_t pmap, vm_offset_t addr,
 
 		pde = pmap_pde(pmap, addr);
 		if (pde != 0 && (*pde & PG_V) != 0)
-			goto unlock_return;
+			return;
 retry:
 		p = vm_page_lookup(object, pindex);
 		if (p != NULL) {
@@ -2099,14 +2090,14 @@ retry:
 		} else {
 			p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL);
 			if (p == NULL)
-				goto unlock_return;
+				return;
 			m[0] = p;
 
 			if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) {
 				vm_page_lock_queues();
 				vm_page_free(p);
 				vm_page_unlock_queues();
-				goto unlock_return;
+				return;
 			}
 
 			p = vm_page_lookup(object, pindex);
@@ -2116,9 +2107,8 @@ retry:
 		vm_page_unlock_queues();
 
 		ptepa = VM_PAGE_TO_PHYS(p);
-		if (ptepa & (NBPDR - 1)) {
-			goto unlock_return;
-		}
+		if (ptepa & (NBPDR - 1))
+			return;
 
 		p->valid = VM_PAGE_BITS_ALL;
 
@@ -2130,65 +2120,7 @@ retry:
 			pde++;
 		}
 		pmap_invalidate_all(kernel_pmap);
-		goto unlock_return;
-	}
-
-	psize = amd64_btop(size);
-
-	if ((object->type != OBJT_VNODE) ||
-	    ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) &&
-	     (object->resident_page_count > MAX_INIT_PT))) {
-		goto unlock_return;
-	}
-
-	if (psize + pindex > object->size) {
-		if (object->size < pindex)
-			goto unlock_return;
-		psize = object->size - pindex;
-	}
-
-	mpte = NULL;
-
-	if ((p = TAILQ_FIRST(&object->memq)) != NULL) {
-		if (p->pindex < pindex) {
-			p = vm_page_splay(pindex, object->root);
-			if ((object->root = p)->pindex < pindex)
-				p = TAILQ_NEXT(p, listq);
-		}
-	}
-	/*
-	 * Assert: the variable p is either (1) the page with the
-	 * least pindex greater than or equal to the parameter pindex
-	 * or (2) NULL.
-	 */
-	for (;
-	     p != NULL && (tmpidx = p->pindex - pindex) < psize;
-	     p = TAILQ_NEXT(p, listq)) {
-		/*
-		 * don't allow an madvise to blow away our really
-		 * free pages allocating pv entries.
-		 */
-		if ((limit & MAP_PREFAULT_MADVISE) &&
-		    cnt.v_free_count < cnt.v_free_reserved) {
-			break;
-		}
-		vm_page_lock_queues();
-		if ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL &&
-		    (p->busy == 0) &&
-		    (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) {
-			if ((p->queue - p->pc) == PQ_CACHE)
-				vm_page_deactivate(p);
-			vm_page_busy(p);
-			vm_page_unlock_queues();
-			mpte = pmap_enter_quick(pmap, 
-				addr + amd64_ptob(tmpidx), p, mpte);
-			vm_page_lock_queues();
-			vm_page_wakeup(p);
-		}
-		vm_page_unlock_queues();
 	}
-unlock_return:
-	VM_OBJECT_UNLOCK(object);
 }
 
 /*