from netbsd:

Extend use of vm_object_prefer() to vm_allocate_with_pager().
Make vm_object_prefer() call MD aligner for "pageless" objects too,
so we can have more control over the virtual address to be used.

Implementation could be simpler if we by-pass the object to mapped, but
we'd loose the ability to adapt alignment to objects that were previously
mmap'ed with MAP_FIXED on.

Only expect vm_fork() to return if __FORK_BRAINDAMAGE is defined.
Eliminate unused third arg to vm_fork().

5 files changed, 87 insertions, 42 deletions

diff --git a/sys/vm/vm_extern.h b/sys/vm/vm_extern.h
index 91e0417c78f..cca6f755a64 100644
--- a/sys/vm/vm_extern.h
+++ b/sys/vm/vm_extern.h
@@ -1,4 +1,4 @@
-/*	$NetBSD: vm_extern.h,v 1.14 1995/09/27 20:30:17 thorpej Exp $	*/
+/*	$NetBSD: vm_extern.h,v 1.15 1995/12/09 04:28:16 mycroft Exp $	*/
 
 /*-
  * Copyright (c) 1992, 1993
@@ -103,7 +103,11 @@ void		 vm_fault_copy_entry __P((vm_map_t,
 		    vm_map_t, vm_map_entry_t, vm_map_entry_t));
 void		 vm_fault_unwire __P((vm_map_t, vm_offset_t, vm_offset_t));
 int		 vm_fault_wire __P((vm_map_t, vm_offset_t, vm_offset_t));
-int		 vm_fork __P((struct proc *, struct proc *, int));
+#ifdef __FORK_BRAINDAMAGE
+int		 vm_fork __P((struct proc *, struct proc *));
+#else
+void		 vm_fork __P((struct proc *, struct proc *));
+#endif
 int		 vm_inherit __P((vm_map_t,
 		    vm_offset_t, vm_size_t, vm_inherit_t));
 void		 vm_init_limits __P((struct proc *));
diff --git a/sys/vm/vm_glue.c b/sys/vm/vm_glue.c
index e8a668ec61f..08927c41330 100644
--- a/sys/vm/vm_glue.c
+++ b/sys/vm/vm_glue.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: vm_glue.c,v 1.46 1995/05/05 03:35:39 cgd Exp $	*/
+/*	$NetBSD: vm_glue.c,v 1.48 1995/12/09 04:28:19 mycroft Exp $	*/
 
 /* 
  * Copyright (c) 1991, 1993
@@ -202,10 +202,13 @@ vsunlock(addr, len, dirtied)
  * after cpu_fork returns in the child process.  We do nothing here
  * after cpu_fork returns.
  */
+#ifdef __FORK_BRAINDAMAGE
 int
-vm_fork(p1, p2, isvfork)
+#else
+void
+#endif
+vm_fork(p1, p2)
 	register struct proc *p1, *p2;
-	int isvfork;
 {
 	register struct user *up;
 	vm_offset_t addr;
@@ -222,18 +225,14 @@ vm_fork(p1, p2, isvfork)
 
 #ifdef SYSVSHM
 	if (p1->p_vmspace->vm_shm)
-		shmfork(p1, p2, isvfork);
+		shmfork(p1, p2);
 #endif
 
 #if !defined(i386) && !defined(pc532)
 	/*
 	 * Allocate a wired-down (for now) pcb and kernel stack for the process
 	 */
-#ifdef pica
-	addr = kmem_alloc_upage(kernel_map, USPACE);
-#else
 	addr = kmem_alloc_pageable(kernel_map, USPACE);
-#endif
 	if (addr == 0)
 		panic("vm_fork: no more kernel virtual memory");
 	vm_map_pageable(kernel_map, addr, addr + USPACE, FALSE);
@@ -276,6 +275,8 @@ vm_fork(p1, p2, isvfork)
 	(void)vm_map_inherit(vp, addr, VM_MAX_ADDRESS, VM_INHERIT_NONE);
 	}
 #endif
+
+#ifdef __FORK_BRAINDAMAGE
 	/*
 	 * cpu_fork will copy and update the kernel stack and pcb,
 	 * and make the child ready to run.  It marks the child
@@ -284,6 +285,15 @@ vm_fork(p1, p2, isvfork)
 	 * once in the child.
 	 */
 	return (cpu_fork(p1, p2));
+#else
+	/*
+	 * cpu_fork will copy and update the kernel stack and pcb,
+	 * and make the child ready to run.  The child will exit
+	 * directly to user mode on its first time slice, and will
+	 * not return here.
+	 */
+	cpu_fork(p1, p2);
+#endif
 }
 
 /*
@@ -339,7 +349,7 @@ swapin(p)
 	cpu_swapin(p);
 	s = splstatclock();
 	if (p->p_stat == SRUN)
-	        setrunqueue(p);
+		setrunqueue(p);
 	p->p_flag |= P_INMEM;
 	splx(s);
 	p->p_swtime = 0;
@@ -400,10 +410,6 @@ loop:
 			       p->p_pid, p->p_comm, p->p_addr,
 			       ppri, cnt.v_free_count);
 #endif
-#ifdef pica
-		vm_map_pageable(kernel_map, (vm_offset_t)p->p_addr,
-		    (vm_offset_t)p->p_addr + atop(USPACE), FALSE);
-#endif
 		swapin(p);
 		goto loop;
 	}
diff --git a/sys/vm/vm_mmap.c b/sys/vm/vm_mmap.c
index ea205439963..016dbc9565e 100644
--- a/sys/vm/vm_mmap.c
+++ b/sys/vm/vm_mmap.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: vm_mmap.c,v 1.42 1995/10/10 01:27:11 mycroft Exp $	*/
+/*	$NetBSD: vm_mmap.c,v 1.43 1995/12/05 22:54:42 pk Exp $	*/
 
 /*
  * Copyright (c) 1988 University of Utah.
@@ -827,15 +827,13 @@ vm_mmap(map, addr, size, prot, maxprot, flags, handle, foff)
 			vm_offset_t off;
 
 			/* locate and allocate the target address space */
+			vm_map_lock(map);
 			if (fitit) {
 				/*
-				 * We cannot call vm_map_find() because
-				 * a proposed address may be vetoed by
-				 * the pmap module.
-				 * So we look for space ourselves, validate
-				 * it and insert it into the map. 
+				 * Find space in the map at a location
+				 * that is compatible with the object/offset
+				 * we're going to attach there.
 				 */
-				vm_map_lock(map);
 			again:
 				if (vm_map_findspace(map, *addr, size,
 						     addr) == 1) {
@@ -843,33 +841,40 @@ vm_mmap(map, addr, size, prot, maxprot, flags, handle, foff)
 				} else {
 					vm_object_prefer(object, foff, addr);
 					rv = vm_map_insert(map, NULL,
-							(vm_offset_t)0,
-							*addr, *addr+size);
+							   (vm_offset_t)0,
+							   *addr, *addr+size);
+					/*
+					 * vm_map_insert() may fail if
+					 * vm_object_prefer() has altered
+					 * the initial address.
+					 * If so, we start again.
+					 */
 					if (rv == KERN_NO_SPACE)
-						/*
-						 * Modified address didn't fit
-						 * after all, the gap must
-						 * have been to small.
-						 */
 						goto again;
 				}
-				vm_map_unlock(map);
 			} else {
-				rv = vm_map_find(map, NULL, (vm_offset_t)0,
-					 addr, size, 0);
+				rv = vm_map_insert(map, NULL, (vm_offset_t)0,
+						   *addr, *addr + size);
 
+#ifdef DEBUG
 				/*
 				 * Check against PMAP preferred address. If
 				 * there's a mismatch, these pages should not
 				 * be shared with others. <howto?>
 				 */
-				if (rv == KERN_SUCCESS) {
+				if (rv == KERN_SUCCESS &&
+				    (mmapdebug & MDB_MAPIT)) {
 					vm_offset_t	paddr = *addr;
 					vm_object_prefer(object, foff, &paddr);
 					if (paddr != *addr)
-						printf("vm_mmap: pmap botch!\n");
+					    printf(
+					      "vm_mmap: pmap botch! "
+					      "[foff %x, addr %x, paddr %x]\n",
+					      foff, *addr, paddr);
 				}
+#endif
 			}
+			vm_map_unlock(map);
 
 			if (rv != KERN_SUCCESS) {
 				vm_object_deallocate(object);
@@ -879,7 +884,7 @@ vm_mmap(map, addr, size, prot, maxprot, flags, handle, foff)
 					     VM_MIN_ADDRESS+size, TRUE);
 			off = VM_MIN_ADDRESS;
 			rv = vm_allocate_with_pager(tmap, &off, size,
-						    TRUE, pager,
+						    FALSE, pager,
 						    foff, FALSE);
 			if (rv != KERN_SUCCESS) {
 				vm_object_deallocate(object);
diff --git a/sys/vm/vm_object.c b/sys/vm/vm_object.c
index 2dc50bb47c8..81bb806cfa8 100644
--- a/sys/vm/vm_object.c
+++ b/sys/vm/vm_object.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: vm_object.c,v 1.29 1995/07/13 12:35:29 pk Exp $	*/
+/*	$NetBSD: vm_object.c,v 1.31 1995/12/06 00:38:11 pk Exp $	*/
 
 /* 
  * Copyright (c) 1991, 1993
@@ -1418,17 +1418,17 @@ vm_object_prefer(object, offset, addr)
 	register vm_page_t	p;
 	register vm_offset_t	paddr;
 
+#ifdef PMAP_PREFER
 	if (object == NULL)
-		return;
+		goto first_map;
 
-#ifdef PMAP_PREFER
-	vm_object_lock(object);
 	/*
 	 * Look for the first page that the pmap layer has something
 	 * to say about. Since an object maps a contiguous range of
 	 * virutal addresses, this will determine the preferred origin
 	 * of the proposed mapping.
 	 */
+	vm_object_lock(object);
 	for (p = object->memq.tqh_first; p != NULL; p = p->listq.tqe_next) {
 		if (p->flags & (PG_FAKE | PG_FICTITIOUS))
 			continue;
@@ -1436,9 +1436,20 @@ vm_object_prefer(object, offset, addr)
 		if (paddr == (vm_offset_t)-1)
 			continue;
 		*addr = paddr - (p->offset - offset);
-		break;
+		vm_object_unlock(object);
+		return;
 	}
 	vm_object_unlock(object);
+
+first_map:
+	/*
+	 * No physical page attached; ask for a preferred address based
+	 * only on the given virtual address.
+	 */
+	paddr = PMAP_PREFER((vm_offset_t)-1, *addr);
+	if (paddr != (vm_offset_t)-1)
+		*addr = paddr;
+
 #endif
 }
 /*
diff --git a/sys/vm/vm_user.c b/sys/vm/vm_user.c
index 26d8730445e..e0569fe2eff 100644
--- a/sys/vm/vm_user.c
+++ b/sys/vm/vm_user.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: vm_user.c,v 1.11 1994/10/20 04:27:34 cgd Exp $	*/
+/*	$NetBSD: vm_user.c,v 1.12 1995/12/05 22:54:39 pk Exp $	*/
 
 /* 
  * Copyright (c) 1991, 1993
@@ -276,6 +276,7 @@ vm_allocate_with_pager(map, addr, size, anywhere, pager, poffset, internal)
 {
 	register vm_object_t	object;
 	register int		result;
+	vm_offset_t		start;
 
 	if (map == NULL)
 		return(KERN_INVALID_ARGUMENT);
@@ -309,7 +310,25 @@ vm_allocate_with_pager(map, addr, size, anywhere, pager, poffset, internal)
 		cnt.v_nzfod -= atop(size);
 	}
 
-	result = vm_map_find(map, object, poffset, addr, size, anywhere);
+	start = *addr;
+	vm_map_lock(map);
+	if (anywhere) {
+	again:
+		if (vm_map_findspace(map, start, size, addr))
+			result = KERN_NO_SPACE;
+		else {
+			vm_object_prefer(object, poffset, addr);
+			start = *addr;
+			result = vm_map_insert(map, object, poffset,
+					       start, start + size);
+			if (result == KERN_NO_SPACE)
+				goto again;
+		}
+	} else
+		result = vm_map_insert(map, object, poffset,
+				       start, start + size);
+	vm_map_unlock(map);
+
 	if (result != KERN_SUCCESS)
 		vm_object_deallocate(object);
 	else if (pager != NULL)