Since we've now cleared up a lot of the PG_RELEASED setting, remove the

pgo_releasepg() hook and just free the page the "normal" way in the one
place we'll ever see PG_RELEASED and should care (uvm_page_unbusy,
called in aiodoned).

ok art@, beck@, thib@

8 files changed, 49 insertions, 186 deletions

diff --git a/sys/uvm/uvm_aobj.c b/sys/uvm/uvm_aobj.c
index 0f7770a4707..ad2509f3bc2 100644
--- a/sys/uvm/uvm_aobj.c
+++ b/sys/uvm/uvm_aobj.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_aobj.c,v 1.39 2009/05/08 13:50:15 ariane Exp $	*/
+/*	$OpenBSD: uvm_aobj.c,v 1.40 2009/06/01 19:54:02 oga Exp $	*/
 /*	$NetBSD: uvm_aobj.c,v 1.39 2001/02/18 21:19:08 chs Exp $	*/
 
 /*
@@ -174,7 +174,6 @@ boolean_t		 uao_flush(struct uvm_object *, voff_t, voff_t, int);
 void			 uao_free(struct uvm_aobj *);
 int			 uao_get(struct uvm_object *, voff_t, vm_page_t *,
 			     int *, int, vm_prot_t, int, int);
-boolean_t		 uao_releasepg(struct vm_page *, struct vm_page **);
 boolean_t		 uao_pagein(struct uvm_aobj *, int, int);
 boolean_t		 uao_pagein_page(struct uvm_aobj *, int);
 
@@ -191,10 +190,6 @@ struct uvm_pagerops aobj_pager = {
 	NULL,			/* fault */
 	uao_flush,		/* flush */
 	uao_get,		/* get */
-	NULL,			/* put (done by pagedaemon) */
-	NULL,			/* cluster */
-	NULL,			/* mk_pcluster */
-	uao_releasepg		/* releasepg */
 };
 
 /*
@@ -1142,45 +1137,6 @@ uao_get(struct uvm_object *uobj, voff_t offset, struct vm_page **pps,
 }
 
 /*
- * uao_releasepg: handle released page in an aobj
- * 
- * => "pg" is a PG_BUSY [caller owns it], PG_RELEASED page that we need
- *      to dispose of.
- * => caller must handle PG_WANTED case
- * => called with page's object locked, pageq's unlocked
- * => returns TRUE if page's object is still alive, FALSE if we
- *      killed the page's object.    if we return TRUE, then we
- *      return with the object locked.
- * => if (nextpgp != NULL) => we return the next page on the queue, and return
- *                              with the page queues locked [for pagedaemon]
- * => if (nextpgp == NULL) => we return with page queues unlocked [normal case]
- * => we kill the aobj if it is not referenced and we are suppose to
- *      kill it ("KILLME").
- */
-boolean_t
-uao_releasepg(struct vm_page *pg, struct vm_page **nextpgp /* OUT */)
-{
-	struct uvm_aobj *aobj = (struct uvm_aobj *) pg->uobject;
-
-	KASSERT(pg->pg_flags & PG_RELEASED);
-
-	/*
- 	 * dispose of the page [caller handles PG_WANTED] and swap slot.
- 	 */
-	pmap_page_protect(pg, VM_PROT_NONE);
-	uao_dropswap(&aobj->u_obj, pg->offset >> PAGE_SHIFT);
-	uvm_lock_pageq();
-	if (nextpgp)
-		*nextpgp = TAILQ_NEXT(pg, pageq); /* next page for daemon */
-	uvm_pagefree(pg);
-	if (!nextpgp)
-		uvm_unlock_pageq();		/* keep locked for daemon */
-
-	return TRUE;
-}
-
-
-/*
  * uao_dropswap:  release any swap resources from this aobj page.
  * 
  * => aobj must be locked or have a reference count of 0.
diff --git a/sys/uvm/uvm_fault.c b/sys/uvm/uvm_fault.c
index a596ef1d342..e9b26c9f9bc 100644
--- a/sys/uvm/uvm_fault.c
+++ b/sys/uvm/uvm_fault.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_fault.c,v 1.53 2009/05/08 13:50:15 ariane Exp $	*/
+/*	$OpenBSD: uvm_fault.c,v 1.54 2009/06/01 19:54:02 oga Exp $	*/
 /*	$NetBSD: uvm_fault.c,v 1.51 2000/08/06 00:22:53 thorpej Exp $	*/
 
 /*
@@ -921,10 +921,10 @@ ReFault:
 
 				/*
 				 * if center page is resident and not
-				 * PG_BUSY|PG_RELEASED then pgo_get
-				 * made it PG_BUSY for us and gave
-				 * us a handle to it.   remember this
-				 * page as "uobjpage." (for later use).
+				 * PG_BUSY, then pgo_get made it PG_BUSY
+				 * for us and gave us a handle to it.
+				 * remember this page as "uobjpage."
+				 * (for later use).
 				 */
 				
 				if (lcv == centeridx) {
@@ -966,8 +966,8 @@ ReFault:
 				     (wired ? PMAP_WIRED : 0));
 
 				/* 
-				 * NOTE: page can't be PG_WANTED or PG_RELEASED
-				 * because we've held the lock the whole time
+				 * NOTE: page can't be PG_WANTED because
+				 * we've held the lock the whole time
 				 * we've had the handle.
 				 */
 
@@ -1371,15 +1371,12 @@ Case2:
 		/* locked(!locked): uobj, uobjpage */
 
 		/*
-		 * verify that the page has not be released and re-verify
-		 * that amap slot is still free.   if there is a problem,
-		 * we unlock and clean up.
+		 * Re-verify that amap slot is still free. if there is
+		 * a problem, we unlock and clean up.
 		 */
 
-		if ((uobjpage->pg_flags & PG_RELEASED) != 0 ||
-		    (locked && amap && 
-		    amap_lookup(&ufi.entry->aref,
-		      ufi.orig_rvaddr - ufi.entry->start))) {
+		if (locked && amap && amap_lookup(&ufi.entry->aref,
+		      ufi.orig_rvaddr - ufi.entry->start)) {
 			if (locked) 
 				uvmfault_unlockall(&ufi, amap, NULL, NULL);
 			locked = FALSE;
@@ -1398,17 +1395,6 @@ Case2:
 				/* still holding object lock */
 				wakeup(uobjpage);
 
-			if (uobjpage->pg_flags & PG_RELEASED) {
-				uvmexp.fltpgrele++;
-				KASSERT(uobj->pgops->pgo_releasepg != NULL);
-
-				/* frees page */
-				if (uobj->pgops->pgo_releasepg(uobjpage,NULL))
-					/* unlock if still alive */
-					simple_unlock(&uobj->vmobjlock);
-				goto ReFault;
-			}
-
 			uvm_lock_pageq();
 			/* make sure it is in queues */
 			uvm_pageactivate(uobjpage);
@@ -1423,9 +1409,8 @@ Case2:
 		}
 
 		/*
-		 * we have the data in uobjpage which is PG_BUSY and
-		 * !PG_RELEASED.  we are holding object lock (so the page
-		 * can't be released on us).
+		 * we have the data in uobjpage which is PG_BUSY and we are
+		 * holding object lock.
 		 */
 
 		/* locked: maps(read), amap(if !null), uobj, uobjpage */
@@ -1439,8 +1424,6 @@ Case2:
 	/*
 	 * notes:
 	 *  - at this point uobjpage can not be NULL
-	 *  - at this point uobjpage can not be PG_RELEASED (since we checked
-	 *  for it above)
 	 *  - at this point uobjpage could be PG_WANTED (handle later)
 	 */
 		
@@ -1627,9 +1610,7 @@ Case2:
 			}
 			
 			/*
-			 * dispose of uobjpage.  it can't be PG_RELEASED
-			 * since we still hold the object lock.
-			 * drop handle to uobj as well.
+			 * dispose of uobjpage. drop handle to uobj as well.
 			 */
 
 			if (uobjpage->pg_flags & PG_WANTED)
@@ -1692,11 +1673,6 @@ Case2:
 		if (pg->pg_flags & PG_WANTED)
 			wakeup(pg);		/* lock still held */
 
-		/* 
-		 * note that pg can't be PG_RELEASED since we did not drop
-		 * the object lock since the last time we checked.
-		 */
- 
 		atomic_clearbits_int(&pg->pg_flags, PG_BUSY|PG_FAKE|PG_WANTED);
 		UVM_PAGE_OWN(pg, NULL);
 		uvmfault_unlockall(&ufi, amap, uobj, NULL);
@@ -1736,11 +1712,6 @@ Case2:
 	if (pg->pg_flags & PG_WANTED)
 		wakeup(pg);		/* lock still held */
 
-	/* 
-	 * note that pg can't be PG_RELEASED since we did not drop the object 
-	 * lock since the last time we checked.
-	 */
- 
 	atomic_clearbits_int(&pg->pg_flags, PG_BUSY|PG_FAKE|PG_WANTED);
 	UVM_PAGE_OWN(pg, NULL);
 	uvmfault_unlockall(&ufi, amap, uobj, NULL);
diff --git a/sys/uvm/uvm_loan.c b/sys/uvm/uvm_loan.c
index 989d0bb2867..b4f62568fd7 100644
--- a/sys/uvm/uvm_loan.c
+++ b/sys/uvm/uvm_loan.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_loan.c,v 1.30 2009/05/08 13:50:15 ariane Exp $	*/
+/*	$OpenBSD: uvm_loan.c,v 1.31 2009/06/01 19:54:02 oga Exp $	*/
 /*	$NetBSD: uvm_loan.c,v 1.22 2000/06/27 17:29:25 mrg Exp $	*/
 
 /*
@@ -462,14 +462,12 @@ uvm_loanuobj(struct uvm_faultinfo *ufi, void ***output, int flags, vaddr_t va)
 		simple_lock(&uobj->vmobjlock);
 
 		/*
-		 * verify that the page has not be released and re-verify
-		 * that amap slot is still free.   if there is a problem we
-		 * drop our lock (thus force a lookup refresh/retry).
+		 * Re-verify that amap slot is still free. if there is a
+		 * problem we drop our lock (thus force a lookup refresh/retry).
 		 */
 			
-		if ((pg->pg_flags & PG_RELEASED) != 0 ||
-		    (locked && amap && amap_lookup(&ufi->entry->aref,
-		    ufi->orig_rvaddr - ufi->entry->start))) {
+		if (locked && amap && amap_lookup(&ufi->entry->aref,
+		    ufi->orig_rvaddr - ufi->entry->start)) {
 			
 			if (locked)
 				uvmfault_unlockall(ufi, amap, NULL, NULL);
@@ -486,17 +484,6 @@ uvm_loanuobj(struct uvm_faultinfo *ufi, void ***output, int flags, vaddr_t va)
 				/* still holding object lock */
 				wakeup(pg);
 
-			if (pg->pg_flags & PG_RELEASED) {
-#ifdef DIAGNOSTIC
-				if (uobj->pgops->pgo_releasepg == NULL)
-			panic("uvm_loanuobj: object has no releasepg function");
-#endif
-				/* frees page */
-				if (uobj->pgops->pgo_releasepg(pg, NULL))
-					simple_unlock(&uobj->vmobjlock);
-				return (0);
-			}
-
 			uvm_lock_pageq();
 			uvm_pageactivate(pg); /* make sure it is in queues */
 			uvm_unlock_pageq();
@@ -509,8 +496,7 @@ uvm_loanuobj(struct uvm_faultinfo *ufi, void ***output, int flags, vaddr_t va)
 
 	/*
 	 * at this point we have the page we want ("pg") marked PG_BUSY for us
-	 * and we have all data structures locked.   do the loanout.   page can
-	 * not be PG_RELEASED (we caught this above).
+	 * and we have all data structures locked.   do the loanout.
 	 */
 
 	if ((flags & UVM_LOAN_TOANON) == 0) {	/* loan to wired-kernel page? */
diff --git a/sys/uvm/uvm_mmap.c b/sys/uvm/uvm_mmap.c
index 685eb5d341e..76d65abd04d 100644
--- a/sys/uvm/uvm_mmap.c
+++ b/sys/uvm/uvm_mmap.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_mmap.c,v 1.72 2009/03/20 15:19:04 oga Exp $	*/
+/*	$OpenBSD: uvm_mmap.c,v 1.73 2009/06/01 19:54:02 oga Exp $	*/
 /*	$NetBSD: uvm_mmap.c,v 1.49 2001/02/18 21:19:08 chs Exp $	*/
 
 /*
@@ -298,8 +298,7 @@ sys_mincore(struct proc *p, void *v, register_t *retval)
 		 */
 		if (UVM_ET_ISOBJ(entry)) {
 			KASSERT(!UVM_OBJ_IS_KERN_OBJECT(entry->object.uvm_obj));
-			if (entry->object.uvm_obj->pgops->pgo_releasepg
-			    == NULL) {
+			if (entry->object.uvm_obj->pgops->pgo_fault != NULL) {
 				pgi = 1;
 				for (/* nothing */; start < lim;
 				     start += PAGE_SIZE, vec++)
diff --git a/sys/uvm/uvm_page.c b/sys/uvm/uvm_page.c
index 7c6e257ccb5..1d88b3b5209 100644
--- a/sys/uvm/uvm_page.c
+++ b/sys/uvm/uvm_page.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_page.c,v 1.81 2009/06/01 17:42:33 ariane Exp $	*/
+/*	$OpenBSD: uvm_page.c,v 1.82 2009/06/01 19:54:02 oga Exp $	*/
 /*	$NetBSD: uvm_page.c,v 1.44 2000/11/27 08:40:04 chs Exp $	*/
 
 /* 
@@ -1168,7 +1168,14 @@ uvm_page_unbusy(struct vm_page **pgs, int npgs)
 			UVMHIST_LOG(pdhist, "releasing pg %p", pg,0,0,0);
 			uobj = pg->uobject;
 			if (uobj != NULL) {
-				uobj->pgops->pgo_releasepg(pg, NULL);
+				uvm_lock_pageq();
+				pmap_page_protect(pg, VM_PROT_NONE);
+				/* XXX won't happen right now */
+				if (pg->pg_flags & PQ_ANON)
+					uao_dropswap(uobj,
+					    pg->offset >> PAGE_SHIFT);
+				uvm_pagefree(pg);
+				uvm_unlock_pageq();
 			} else {
 				atomic_clearbits_int(&pg->pg_flags, PG_BUSY);
 				UVM_PAGE_OWN(pg, NULL);
diff --git a/sys/uvm/uvm_pager.h b/sys/uvm/uvm_pager.h
index 229303e5247..5b820ea65b3 100644
--- a/sys/uvm/uvm_pager.h
+++ b/sys/uvm/uvm_pager.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_pager.h,v 1.23 2009/03/27 16:29:33 oga Exp $	*/
+/*	$OpenBSD: uvm_pager.h,v 1.24 2009/06/01 19:54:02 oga Exp $	*/
 /*	$NetBSD: uvm_pager.h,v 1.20 2000/11/27 08:40:05 chs Exp $	*/
 
 /*
@@ -109,8 +109,6 @@ struct uvm_pagerops {
 	struct vm_page **	(*pgo_mk_pcluster)(struct uvm_object *,
 				 struct vm_page **, int *, struct vm_page *,
 				 int, voff_t, voff_t);
-						/* release page */
-	boolean_t		(*pgo_releasepg)(struct vm_page *, struct vm_page **);
 };
 
 /* pager flags [mostly for flush] */
diff --git a/sys/uvm/uvm_pdaemon.c b/sys/uvm/uvm_pdaemon.c
index e92069c3459..3079110cb1c 100644
--- a/sys/uvm/uvm_pdaemon.c
+++ b/sys/uvm/uvm_pdaemon.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_pdaemon.c,v 1.44 2009/05/08 13:50:15 ariane Exp $	*/
+/*	$OpenBSD: uvm_pdaemon.c,v 1.45 2009/06/01 19:54:02 oga Exp $	*/
 /*	$NetBSD: uvm_pdaemon.c,v 1.23 2000/08/20 10:24:14 bjh21 Exp $	*/
 
 /* 
@@ -820,35 +820,20 @@ uvmpd_scan_inactive(struct pglist *pglst)
 			atomic_clearbits_int(&p->pg_flags, PG_BUSY|PG_WANTED);
 			UVM_PAGE_OWN(p, NULL);
 
-			/* released during I/O? */
+			/* released during I/O? Can only happen for anons */
 			if (p->pg_flags & PG_RELEASED) {
-				if (anon) {
-					/* remove page so we can get nextpg */
-					anon->an_page = NULL;
-
-					simple_unlock(&anon->an_lock);
-					uvm_anfree(anon);	/* kills anon */
-					pmap_page_protect(p, VM_PROT_NONE);
-					anon = NULL;
-					uvm_lock_pageq();
-					nextpg = TAILQ_NEXT(p, pageq);
-					/* free released page */
-					uvm_pagefree(p);
-
-				} else {
-
-					/*
-					 * pgo_releasepg nukes the page and
-					 * gets "nextpg" for us.  it returns
-					 * with the page queues locked (when
-					 * given nextpg ptr).
-					 */
+				KASSERT(anon != NULL);
+				/* remove page so we can get nextpg */
+				anon->an_page = NULL;
 
-					if (!uobj->pgops->pgo_releasepg(p,
-					    &nextpg))
-						/* uobj died after release */
-						uobj = NULL;
-				}
+				simple_unlock(&anon->an_lock);
+				uvm_anfree(anon);	/* kills anon */
+				pmap_page_protect(p, VM_PROT_NONE);
+				anon = NULL;
+				uvm_lock_pageq();
+				nextpg = TAILQ_NEXT(p, pageq);
+				/* free released page */
+				uvm_pagefree(p);
 			} else {	/* page was not released during I/O */
 				uvm_lock_pageq();
 				nextpg = TAILQ_NEXT(p, pageq);
diff --git a/sys/uvm/uvm_vnode.c b/sys/uvm/uvm_vnode.c
index 2e4870b745d..f52f6921336 100644
--- a/sys/uvm/uvm_vnode.c
+++ b/sys/uvm/uvm_vnode.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_vnode.c,v 1.59 2009/06/01 17:42:33 ariane Exp $	*/
+/*	$OpenBSD: uvm_vnode.c,v 1.60 2009/06/01 19:54:02 oga Exp $	*/
 /*	$NetBSD: uvm_vnode.c,v 1.36 2000/11/24 20:34:01 chs Exp $	*/
 
 /*
@@ -93,7 +93,6 @@ void		 uvn_init(void);
 int		 uvn_io(struct uvm_vnode *, vm_page_t *, int, int, int);
 int		 uvn_put(struct uvm_object *, vm_page_t *, int, boolean_t);
 void		 uvn_reference(struct uvm_object *);
-boolean_t	 uvn_releasepg(struct vm_page *, struct vm_page **);
 
 /*
  * master pager structure
@@ -109,7 +108,6 @@ struct uvm_pagerops uvm_vnodeops = {
 	uvn_put,
 	uvn_cluster,
 	uvm_mk_pcluster, /* use generic version of this: see uvm_pager.c */
-	uvn_releasepg,
 };
 
 /*
@@ -526,8 +524,8 @@ uvm_vnp_terminate(struct vnode *vp)
 
 	/*
 	 * it is possible that the uvn was detached and is in the relkill
-	 * state [i.e. waiting for async i/o to finish so that releasepg can
-	 * kill object].  we take over the vnode now and cancel the relkill.
+	 * state [i.e. waiting for async i/o to finish].
+	 * we take over the vnode now and cancel the relkill.
 	 * we want to know when the i/o is done so we can recycle right
 	 * away.   note that a uvn can only be in the RELKILL state if it
 	 * has a zero reference count.
@@ -621,41 +619,6 @@ uvm_vnp_terminate(struct vnode *vp)
 }
 
 /*
- * uvn_releasepg: handled a released page in a uvn
- *
- * => "pg" is a PG_BUSY [caller owns it], PG_RELEASED page that we need
- *	to dispose of.
- * => caller must handled PG_WANTED case
- * => called with page's object locked, pageq's unlocked
- * => returns TRUE if page's object is still alive, FALSE if we
- *	killed the page's object.    if we return TRUE, then we
- *	return with the object locked.
- * => if (nextpgp != NULL) => we return pageq.tqe_next here, and return
- *				with the page queues locked [for pagedaemon]
- * => if (nextpgp == NULL) => we return with page queues unlocked [normal case]
- * => we kill the uvn if it is not referenced and we are suppose to
- *	kill it ("relkill").
- */
-
-boolean_t
-uvn_releasepg(struct vm_page *pg, struct vm_page **nextpgp /* OUT */)
-{
-	KASSERT(pg->pg_flags & PG_RELEASED);
-
-	/*
-	 * dispose of the page [caller handles PG_WANTED]
-	 */
-	pmap_page_protect(pg, VM_PROT_NONE);
-	uvm_lock_pageq();
-	if (nextpgp)
-		*nextpgp = TAILQ_NEXT(pg, pageq); /* next page for daemon */
-	uvm_pagefree(pg);
-	if (!nextpgp)
-		uvm_unlock_pageq();
-	return (TRUE);
-}
-
-/*
  * NOTE: currently we have to use VOP_READ/VOP_WRITE because they go
  * through the buffer cache and allow I/O in any size.  These VOPs use
  * synchronous i/o.  [vs. VOP_STRATEGY which can be async, but doesn't
@@ -689,8 +652,6 @@ uvn_releasepg(struct vm_page *pg, struct vm_page **nextpgp /* OUT */)
  * - if (object->iosync && u_naio == 0) { wakeup &uvn->u_naio }
  * - get "page" structures (atop?).
  * - handle "wanted" pages
- * - handle "released" pages [using pgo_releasepg]
- *   >>> pgo_releasepg may kill the object
  * dont forget to look at "object" wanted flag in all cases.
  */