719 lines
20 KiB
C
719 lines
20 KiB
C
/* $NetBSD: uvm_pager.c,v 1.31 2000/06/26 14:21:18 mrg Exp $ */
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/*
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*
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* Copyright (c) 1997 Charles D. Cranor and Washington University.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by Charles D. Cranor and
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* Washington University.
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* 4. The name of the author may not be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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* from: Id: uvm_pager.c,v 1.1.2.23 1998/02/02 20:38:06 chuck Exp
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*/
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#include "opt_uvmhist.h"
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/*
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* uvm_pager.c: generic functions used to assist the pagers.
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*/
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/proc.h>
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#include <sys/malloc.h>
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#include <vm/vm.h>
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#define UVM_PAGER
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#include <uvm/uvm.h>
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/*
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* list of uvm pagers in the system
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*/
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extern struct uvm_pagerops uvm_deviceops;
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extern struct uvm_pagerops uvm_vnodeops;
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struct uvm_pagerops *uvmpagerops[] = {
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&aobj_pager,
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&uvm_deviceops,
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&uvm_vnodeops,
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};
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/*
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* the pager map: provides KVA for I/O
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*/
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#define PAGER_MAP_SIZE (4 * 1024 * 1024)
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vm_map_t pager_map; /* XXX */
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simple_lock_data_t pager_map_wanted_lock;
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boolean_t pager_map_wanted; /* locked by pager map */
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/*
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* uvm_pager_init: init pagers (at boot time)
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*/
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void
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uvm_pager_init()
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{
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int lcv;
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/*
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* init pager map
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*/
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pager_map = uvm_km_suballoc(kernel_map, &uvm.pager_sva, &uvm.pager_eva,
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PAGER_MAP_SIZE, 0, FALSE, NULL);
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simple_lock_init(&pager_map_wanted_lock);
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pager_map_wanted = FALSE;
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/*
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* init ASYNC I/O queue
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*/
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TAILQ_INIT(&uvm.aio_done);
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/*
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* call pager init functions
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*/
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for (lcv = 0 ; lcv < sizeof(uvmpagerops)/sizeof(struct uvm_pagerops *);
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lcv++) {
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if (uvmpagerops[lcv]->pgo_init)
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uvmpagerops[lcv]->pgo_init();
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}
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}
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/*
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* uvm_pagermapin: map pages into KVA (pager_map) for I/O that needs mappings
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*
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* we basically just map in a blank map entry to reserve the space in the
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* map and then use pmap_enter() to put the mappings in by hand.
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*/
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vaddr_t
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uvm_pagermapin(pps, npages, aiop, flags)
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struct vm_page **pps;
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int npages;
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struct uvm_aiodesc **aiop; /* OUT */
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int flags;
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{
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vsize_t size;
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vaddr_t kva;
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struct uvm_aiodesc *aio;
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vaddr_t cva;
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struct vm_page *pp;
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vm_prot_t prot;
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UVMHIST_FUNC("uvm_pagermapin"); UVMHIST_CALLED(maphist);
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UVMHIST_LOG(maphist,"(pps=0x%x, npages=%d, aiop=0x%x, flags=0x%x)",
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pps, npages, aiop, flags);
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/*
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* compute protection. outgoing I/O only needs read
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* access to the page, whereas incoming needs read/write.
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*/
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prot = VM_PROT_READ;
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if (flags & UVMPAGER_MAPIN_READ)
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prot |= VM_PROT_WRITE;
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ReStart:
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if (aiop) {
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MALLOC(aio, struct uvm_aiodesc *, sizeof(*aio), M_TEMP,
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(flags & UVMPAGER_MAPIN_WAITOK));
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if (aio == NULL)
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return(0);
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*aiop = aio;
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} else {
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aio = NULL;
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}
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size = npages << PAGE_SHIFT;
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kva = 0; /* let system choose VA */
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if (uvm_map(pager_map, &kva, size, NULL,
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UVM_UNKNOWN_OFFSET, UVM_FLAG_NOMERGE) != KERN_SUCCESS) {
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if ((flags & UVMPAGER_MAPIN_WAITOK) == 0) {
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if (aio)
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FREE(aio, M_TEMP);
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UVMHIST_LOG(maphist,"<- NOWAIT failed", 0,0,0,0);
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return(0);
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}
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simple_lock(&pager_map_wanted_lock);
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pager_map_wanted = TRUE;
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UVMHIST_LOG(maphist, " SLEEPING on pager_map",0,0,0,0);
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UVM_UNLOCK_AND_WAIT(pager_map, &pager_map_wanted_lock, FALSE,
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"pager_map",0);
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goto ReStart;
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}
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/* got it */
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for (cva = kva ; size != 0 ; size -= PAGE_SIZE, cva += PAGE_SIZE) {
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pp = *pps++;
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#ifdef DEBUG
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if ((pp->flags & PG_BUSY) == 0)
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panic("uvm_pagermapin: page not busy");
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#endif
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pmap_enter(vm_map_pmap(pager_map), cva, VM_PAGE_TO_PHYS(pp),
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prot, PMAP_WIRED | prot);
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}
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UVMHIST_LOG(maphist, "<- done (KVA=0x%x)", kva,0,0,0);
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return(kva);
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}
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/*
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* uvm_pagermapout: remove pager_map mapping
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*
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* we remove our mappings by hand and then remove the mapping (waking
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* up anyone wanting space).
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*/
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void
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uvm_pagermapout(kva, npages)
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vaddr_t kva;
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int npages;
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{
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vsize_t size = npages << PAGE_SHIFT;
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vm_map_entry_t entries;
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UVMHIST_FUNC("uvm_pagermapout"); UVMHIST_CALLED(maphist);
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UVMHIST_LOG(maphist, " (kva=0x%x, npages=%d)", kva, npages,0,0);
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/*
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* duplicate uvm_unmap, but add in pager_map_wanted handling.
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*/
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vm_map_lock(pager_map);
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(void) uvm_unmap_remove(pager_map, kva, kva + size, &entries);
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simple_lock(&pager_map_wanted_lock);
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if (pager_map_wanted) {
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pager_map_wanted = FALSE;
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wakeup(pager_map);
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}
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simple_unlock(&pager_map_wanted_lock);
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vm_map_unlock(pager_map);
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if (entries)
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uvm_unmap_detach(entries, 0);
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UVMHIST_LOG(maphist,"<- done",0,0,0,0);
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}
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/*
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* uvm_mk_pcluster
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*
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* generic "make 'pager put' cluster" function. a pager can either
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* [1] set pgo_mk_pcluster to NULL (never cluster), [2] set it to this
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* generic function, or [3] set it to a pager specific function.
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*
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* => caller must lock object _and_ pagequeues (since we need to look
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* at active vs. inactive bits, etc.)
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* => caller must make center page busy and write-protect it
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* => we mark all cluster pages busy for the caller
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* => the caller must unbusy all pages (and check wanted/released
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* status if it drops the object lock)
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* => flags:
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* PGO_ALLPAGES: all pages in object are valid targets
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* !PGO_ALLPAGES: use "lo" and "hi" to limit range of cluster
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* PGO_DOACTCLUST: include active pages in cluster.
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* NOTE: the caller should clear PG_CLEANCHK bits if PGO_DOACTCLUST.
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* PG_CLEANCHK is only a hint, but clearing will help reduce
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* the number of calls we make to the pmap layer.
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*/
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struct vm_page **
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uvm_mk_pcluster(uobj, pps, npages, center, flags, mlo, mhi)
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struct uvm_object *uobj; /* IN */
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struct vm_page **pps, *center; /* IN/OUT, IN */
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int *npages, flags; /* IN/OUT, IN */
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voff_t mlo, mhi; /* IN (if !PGO_ALLPAGES) */
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{
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struct vm_page **ppsp, *pclust;
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voff_t lo, hi, curoff;
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int center_idx, forward;
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UVMHIST_FUNC("uvm_mk_pcluster"); UVMHIST_CALLED(maphist);
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/*
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* center page should already be busy and write protected. XXX:
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* suppose page is wired? if we lock, then a process could
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* fault/block on it. if we don't lock, a process could write the
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* pages in the middle of an I/O. (consider an msync()). let's
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* lock it for now (better to delay than corrupt data?).
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*/
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/*
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* get cluster boundaries, check sanity, and apply our limits as well.
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*/
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uobj->pgops->pgo_cluster(uobj, center->offset, &lo, &hi);
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if ((flags & PGO_ALLPAGES) == 0) {
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if (lo < mlo)
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lo = mlo;
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if (hi > mhi)
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hi = mhi;
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}
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if ((hi - lo) >> PAGE_SHIFT > *npages) { /* pps too small, bail out! */
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#ifdef DIAGNOSTIC
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printf("uvm_mk_pcluster: provided page array too small (fixed)\n");
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#endif
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pps[0] = center;
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*npages = 1;
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return(pps);
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}
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/*
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* now determine the center and attempt to cluster around the
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* edges
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*/
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center_idx = (center->offset - lo) >> PAGE_SHIFT;
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pps[center_idx] = center; /* plug in the center page */
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ppsp = &pps[center_idx];
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*npages = 1;
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/*
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* attempt to cluster around the left [backward], and then
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* the right side [forward].
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*
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* note that for inactive pages (pages that have been deactivated)
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* there are no valid mappings and PG_CLEAN should be up to date.
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* [i.e. there is no need to query the pmap with pmap_is_modified
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* since there are no mappings].
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*/
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for (forward = 0 ; forward <= 1 ; forward++) {
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curoff = center->offset + (forward ? PAGE_SIZE : -PAGE_SIZE);
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for ( ;(forward == 0 && curoff >= lo) ||
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(forward && curoff < hi);
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curoff += (forward ? 1 : -1) << PAGE_SHIFT) {
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pclust = uvm_pagelookup(uobj, curoff); /* lookup page */
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if (pclust == NULL)
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break; /* no page */
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/* handle active pages */
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/* NOTE: inactive pages don't have pmap mappings */
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if ((pclust->pqflags & PQ_INACTIVE) == 0) {
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if ((flags & PGO_DOACTCLUST) == 0)
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/* dont want mapped pages at all */
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break;
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/* make sure "clean" bit is sync'd */
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if ((pclust->flags & PG_CLEANCHK) == 0) {
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if ((pclust->flags & (PG_CLEAN|PG_BUSY))
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== PG_CLEAN &&
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pmap_is_modified(pclust))
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pclust->flags &= ~PG_CLEAN;
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/* now checked */
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pclust->flags |= PG_CLEANCHK;
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}
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}
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/* is page available for cleaning and does it need it */
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if ((pclust->flags & (PG_CLEAN|PG_BUSY)) != 0)
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break; /* page is already clean or is busy */
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/* yes! enroll the page in our array */
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pclust->flags |= PG_BUSY; /* busy! */
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UVM_PAGE_OWN(pclust, "uvm_mk_pcluster");
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/* XXX: protect wired page? see above comment. */
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pmap_page_protect(pclust, VM_PROT_READ);
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if (!forward) {
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ppsp--; /* back up one page */
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*ppsp = pclust;
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} else {
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/* move forward one page */
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ppsp[*npages] = pclust;
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}
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*npages = *npages + 1;
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}
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}
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/*
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* done! return the cluster array to the caller!!!
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*/
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UVMHIST_LOG(maphist, "<- done",0,0,0,0);
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return(ppsp);
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}
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/*
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* uvm_pager_put: high level pageout routine
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*
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* we want to pageout page "pg" to backing store, clustering if
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* possible.
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*
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* => page queues must be locked by caller
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* => if page is not swap-backed, then "uobj" points to the object
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* backing it. this object should be locked by the caller.
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* => if page is swap-backed, then "uobj" should be NULL.
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* => "pg" should be PG_BUSY (by caller), and !PG_CLEAN
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* for swap-backed memory, "pg" can be NULL if there is no page
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* of interest [sometimes the case for the pagedaemon]
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* => "ppsp_ptr" should point to an array of npages vm_page pointers
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* for possible cluster building
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* => flags (first two for non-swap-backed pages)
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* PGO_ALLPAGES: all pages in uobj are valid targets
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* PGO_DOACTCLUST: include "PQ_ACTIVE" pages as valid targets
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* PGO_SYNCIO: do SYNC I/O (no async)
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* PGO_PDFREECLUST: pagedaemon: drop cluster on successful I/O
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* => start/stop: if (uobj && !PGO_ALLPAGES) limit targets to this range
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* if (!uobj) start is the (daddr_t) of the starting swapblk
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* => return state:
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* 1. we return the VM_PAGER status code of the pageout
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* 2. we return with the page queues unlocked
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* 3. if (uobj != NULL) [!swap_backed] we return with
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* uobj locked _only_ if PGO_PDFREECLUST is set
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* AND result != VM_PAGER_PEND. in all other cases
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* we return with uobj unlocked. [this is a hack
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* that allows the pagedaemon to save one lock/unlock
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* pair in the !swap_backed case since we have to
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* lock the uobj to drop the cluster anyway]
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* 4. on errors we always drop the cluster. thus, if we return
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* !PEND, !OK, then the caller only has to worry about
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* un-busying the main page (not the cluster pages).
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* 5. on success, if !PGO_PDFREECLUST, we return the cluster
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* with all pages busy (caller must un-busy and check
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* wanted/released flags).
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*/
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int
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uvm_pager_put(uobj, pg, ppsp_ptr, npages, flags, start, stop)
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struct uvm_object *uobj; /* IN */
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struct vm_page *pg, ***ppsp_ptr;/* IN, IN/OUT */
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int *npages; /* IN/OUT */
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int flags; /* IN */
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voff_t start, stop; /* IN, IN */
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{
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int result;
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daddr_t swblk;
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struct vm_page **ppsp = *ppsp_ptr;
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/*
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* note that uobj is null if we are doing a swap-backed pageout.
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* note that uobj is !null if we are doing normal object pageout.
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* note that the page queues must be locked to cluster.
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*/
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if (uobj) { /* if !swap-backed */
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/*
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* attempt to build a cluster for pageout using its
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* make-put-cluster function (if it has one).
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*/
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if (uobj->pgops->pgo_mk_pcluster) {
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ppsp = uobj->pgops->pgo_mk_pcluster(uobj, ppsp,
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npages, pg, flags, start, stop);
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*ppsp_ptr = ppsp; /* update caller's pointer */
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} else {
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ppsp[0] = pg;
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*npages = 1;
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}
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swblk = 0; /* XXX: keep gcc happy */
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} else {
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/*
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* for swap-backed pageout, the caller (the pagedaemon) has
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* already built the cluster for us. the starting swap
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* block we are writing to has been passed in as "start."
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* "pg" could be NULL if there is no page we are especially
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* interested in (in which case the whole cluster gets dropped
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* in the event of an error or a sync "done").
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*/
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swblk = (daddr_t) start;
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/* ppsp and npages should be ok */
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}
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/* now that we've clustered we can unlock the page queues */
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uvm_unlock_pageq();
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/*
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* now attempt the I/O. if we have a failure and we are
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* clustered, we will drop the cluster and try again.
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*/
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ReTry:
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if (uobj) {
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/* object is locked */
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result = uobj->pgops->pgo_put(uobj, ppsp, *npages,
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flags & PGO_SYNCIO);
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/* object is now unlocked */
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} else {
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/* nothing locked */
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result = uvm_swap_put(swblk, ppsp, *npages, flags & PGO_SYNCIO);
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/* nothing locked */
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}
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/*
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* we have attempted the I/O.
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*
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* if the I/O was a success then:
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* if !PGO_PDFREECLUST, we return the cluster to the
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* caller (who must un-busy all pages)
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* else we un-busy cluster pages for the pagedaemon
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*
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* if I/O is pending (async i/o) then we return the pending code.
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* [in this case the async i/o done function must clean up when
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* i/o is done...]
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*/
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|
|
if (result == VM_PAGER_PEND || result == VM_PAGER_OK) {
|
|
if (result == VM_PAGER_OK && (flags & PGO_PDFREECLUST)) {
|
|
/*
|
|
* drop cluster and relock object (only if I/O is
|
|
* not pending)
|
|
*/
|
|
if (uobj)
|
|
/* required for dropcluster */
|
|
simple_lock(&uobj->vmobjlock);
|
|
if (*npages > 1 || pg == NULL)
|
|
uvm_pager_dropcluster(uobj, pg, ppsp, npages,
|
|
PGO_PDFREECLUST);
|
|
/* if (uobj): object still locked, as per
|
|
* return-state item #3 */
|
|
}
|
|
return (result);
|
|
}
|
|
|
|
/*
|
|
* a pager error occured.
|
|
* for transient errors, drop to a cluster of 1 page ("pg")
|
|
* and try again. for hard errors, don't bother retrying.
|
|
*/
|
|
|
|
if (*npages > 1 || pg == NULL) {
|
|
if (uobj) {
|
|
simple_lock(&uobj->vmobjlock);
|
|
}
|
|
uvm_pager_dropcluster(uobj, pg, ppsp, npages, PGO_REALLOCSWAP);
|
|
|
|
/*
|
|
* for failed swap-backed pageouts with a "pg",
|
|
* we need to reset pg's swslot to either:
|
|
* "swblk" (for transient errors, so we can retry),
|
|
* or 0 (for hard errors).
|
|
*/
|
|
|
|
if (uobj == NULL && pg != NULL) {
|
|
int nswblk = (result == VM_PAGER_AGAIN) ? swblk : 0;
|
|
if (pg->pqflags & PQ_ANON) {
|
|
simple_lock(&pg->uanon->an_lock);
|
|
pg->uanon->an_swslot = nswblk;
|
|
simple_unlock(&pg->uanon->an_lock);
|
|
} else {
|
|
simple_lock(&pg->uobject->vmobjlock);
|
|
uao_set_swslot(pg->uobject,
|
|
pg->offset >> PAGE_SHIFT,
|
|
nswblk);
|
|
simple_unlock(&pg->uobject->vmobjlock);
|
|
}
|
|
}
|
|
if (result == VM_PAGER_AGAIN) {
|
|
|
|
/*
|
|
* for transient failures, free all the swslots that
|
|
* we're not going to retry with.
|
|
*/
|
|
|
|
if (uobj == NULL) {
|
|
if (pg) {
|
|
uvm_swap_free(swblk + 1, *npages - 1);
|
|
} else {
|
|
uvm_swap_free(swblk, *npages);
|
|
}
|
|
}
|
|
if (pg) {
|
|
ppsp[0] = pg;
|
|
*npages = 1;
|
|
goto ReTry;
|
|
}
|
|
} else if (uobj == NULL) {
|
|
|
|
/*
|
|
* for hard errors on swap-backed pageouts,
|
|
* mark the swslots as bad. note that we do not
|
|
* free swslots that we mark bad.
|
|
*/
|
|
|
|
uvm_swap_markbad(swblk, *npages);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* a pager error occured (even after dropping the cluster, if there
|
|
* was one). give up! the caller only has one page ("pg")
|
|
* to worry about.
|
|
*/
|
|
|
|
if (uobj && (flags & PGO_PDFREECLUST) != 0)
|
|
simple_lock(&uobj->vmobjlock);
|
|
return(result);
|
|
}
|
|
|
|
/*
|
|
* uvm_pager_dropcluster: drop a cluster we have built (because we
|
|
* got an error, or, if PGO_PDFREECLUST we are un-busying the
|
|
* cluster pages on behalf of the pagedaemon).
|
|
*
|
|
* => uobj, if non-null, is a non-swap-backed object that is
|
|
* locked by the caller. we return with this object still
|
|
* locked.
|
|
* => page queues are not locked
|
|
* => pg is our page of interest (the one we clustered around, can be null)
|
|
* => ppsp/npages is our current cluster
|
|
* => flags: PGO_PDFREECLUST: pageout was a success: un-busy cluster
|
|
* pages on behalf of the pagedaemon.
|
|
* PGO_REALLOCSWAP: drop previously allocated swap slots for
|
|
* clustered swap-backed pages (except for "pg" if !NULL)
|
|
* "swblk" is the start of swap alloc (e.g. for ppsp[0])
|
|
* [only meaningful if swap-backed (uobj == NULL)]
|
|
*/
|
|
|
|
void
|
|
uvm_pager_dropcluster(uobj, pg, ppsp, npages, flags)
|
|
struct uvm_object *uobj; /* IN */
|
|
struct vm_page *pg, **ppsp; /* IN, IN/OUT */
|
|
int *npages; /* IN/OUT */
|
|
int flags;
|
|
{
|
|
int lcv;
|
|
boolean_t obj_is_alive;
|
|
struct uvm_object *saved_uobj;
|
|
|
|
/*
|
|
* drop all pages but "pg"
|
|
*/
|
|
|
|
for (lcv = 0 ; lcv < *npages ; lcv++) {
|
|
|
|
if (ppsp[lcv] == pg) /* skip "pg" */
|
|
continue;
|
|
|
|
/*
|
|
* if swap-backed, gain lock on object that owns page. note
|
|
* that PQ_ANON bit can't change as long as we are holding
|
|
* the PG_BUSY bit (so there is no need to lock the page
|
|
* queues to test it).
|
|
*
|
|
* once we have the lock, dispose of the pointer to swap, if
|
|
* requested
|
|
*/
|
|
if (!uobj) {
|
|
if (ppsp[lcv]->pqflags & PQ_ANON) {
|
|
simple_lock(&ppsp[lcv]->uanon->an_lock);
|
|
if (flags & PGO_REALLOCSWAP)
|
|
/* zap swap block */
|
|
ppsp[lcv]->uanon->an_swslot = 0;
|
|
} else {
|
|
simple_lock(&ppsp[lcv]->uobject->vmobjlock);
|
|
if (flags & PGO_REALLOCSWAP)
|
|
uao_set_swslot(ppsp[lcv]->uobject,
|
|
ppsp[lcv]->offset >> PAGE_SHIFT, 0);
|
|
}
|
|
}
|
|
|
|
/* did someone want the page while we had it busy-locked? */
|
|
if (ppsp[lcv]->flags & PG_WANTED)
|
|
/* still holding obj lock */
|
|
wakeup(ppsp[lcv]);
|
|
|
|
/* if page was released, release it. otherwise un-busy it */
|
|
if (ppsp[lcv]->flags & PG_RELEASED) {
|
|
|
|
if (ppsp[lcv]->pqflags & PQ_ANON) {
|
|
/* so that anfree will free */
|
|
ppsp[lcv]->flags &= ~(PG_BUSY);
|
|
UVM_PAGE_OWN(ppsp[lcv], NULL);
|
|
|
|
pmap_page_protect(ppsp[lcv], VM_PROT_NONE);
|
|
simple_unlock(&ppsp[lcv]->uanon->an_lock);
|
|
/* kills anon and frees pg */
|
|
uvm_anfree(ppsp[lcv]->uanon);
|
|
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* pgo_releasepg will dump the page for us
|
|
*/
|
|
|
|
#ifdef DIAGNOSTIC
|
|
if (ppsp[lcv]->uobject->pgops->pgo_releasepg == NULL)
|
|
panic("uvm_pager_dropcluster: no releasepg "
|
|
"function");
|
|
#endif
|
|
saved_uobj = ppsp[lcv]->uobject;
|
|
obj_is_alive =
|
|
saved_uobj->pgops->pgo_releasepg(ppsp[lcv], NULL);
|
|
|
|
#ifdef DIAGNOSTIC
|
|
/* for normal objects, "pg" is still PG_BUSY by us,
|
|
* so obj can't die */
|
|
if (uobj && !obj_is_alive)
|
|
panic("uvm_pager_dropcluster: object died "
|
|
"with active page");
|
|
#endif
|
|
/* only unlock the object if it is still alive... */
|
|
if (obj_is_alive && saved_uobj != uobj)
|
|
simple_unlock(&saved_uobj->vmobjlock);
|
|
|
|
/*
|
|
* XXXCDC: suppose uobj died in the pgo_releasepg?
|
|
* how pass that
|
|
* info up to caller. we are currently ignoring it...
|
|
*/
|
|
|
|
continue; /* next page */
|
|
|
|
} else {
|
|
ppsp[lcv]->flags &= ~(PG_BUSY|PG_WANTED);
|
|
UVM_PAGE_OWN(ppsp[lcv], NULL);
|
|
}
|
|
|
|
/*
|
|
* if we are operating on behalf of the pagedaemon and we
|
|
* had a successful pageout update the page!
|
|
*/
|
|
if (flags & PGO_PDFREECLUST) {
|
|
pmap_clear_reference(ppsp[lcv]);
|
|
pmap_clear_modify(ppsp[lcv]);
|
|
ppsp[lcv]->flags |= PG_CLEAN;
|
|
}
|
|
|
|
/* if anonymous cluster, unlock object and move on */
|
|
if (!uobj) {
|
|
if (ppsp[lcv]->pqflags & PQ_ANON)
|
|
simple_unlock(&ppsp[lcv]->uanon->an_lock);
|
|
else
|
|
simple_unlock(&ppsp[lcv]->uobject->vmobjlock);
|
|
}
|
|
}
|
|
}
|