dd82ad8e2c
the mapping is: VM_PAGER_OK 0 VM_PAGER_BAD <unused> VM_PAGER_FAIL <unused> VM_PAGER_PEND 0 (see below) VM_PAGER_ERROR EIO VM_PAGER_AGAIN EAGAIN VM_PAGER_UNLOCK EBUSY VM_PAGER_REFAULT ERESTART for async i/o requests, it used to be possible for the request to be convert to sync, and the pager would return VM_PAGER_OK or VM_PAGER_PEND to indicate whether the caller should perform post-i/o cleanup. this is no longer allowed; pagers must now return 0 to indicate that the async i/o was successfully started, and the caller never needs to worry about doing the post-i/o cleanup.
871 lines
23 KiB
C
871 lines
23 KiB
C
/* $NetBSD: uvm_pager.c,v 1.42 2001/03/10 22:46:49 chs Exp $ */
|
|
|
|
/*
|
|
*
|
|
* Copyright (c) 1997 Charles D. Cranor and Washington University.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by Charles D. Cranor and
|
|
* Washington University.
|
|
* 4. The name of the author may not be used to endorse or promote products
|
|
* derived from this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
|
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
|
|
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
|
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
* from: Id: uvm_pager.c,v 1.1.2.23 1998/02/02 20:38:06 chuck Exp
|
|
*/
|
|
|
|
#include "opt_uvmhist.h"
|
|
|
|
/*
|
|
* uvm_pager.c: generic functions used to assist the pagers.
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/pool.h>
|
|
#include <sys/vnode.h>
|
|
|
|
#define UVM_PAGER
|
|
#include <uvm/uvm.h>
|
|
|
|
struct pool *uvm_aiobuf_pool;
|
|
|
|
/*
|
|
* list of uvm pagers in the system
|
|
*/
|
|
|
|
extern struct uvm_pagerops uvm_deviceops;
|
|
extern struct uvm_pagerops uvm_vnodeops;
|
|
extern struct uvm_pagerops ubc_pager;
|
|
|
|
struct uvm_pagerops *uvmpagerops[] = {
|
|
&aobj_pager,
|
|
&uvm_deviceops,
|
|
&uvm_vnodeops,
|
|
&ubc_pager,
|
|
};
|
|
|
|
/*
|
|
* the pager map: provides KVA for I/O
|
|
*/
|
|
|
|
vm_map_t pager_map; /* XXX */
|
|
simple_lock_data_t pager_map_wanted_lock;
|
|
boolean_t pager_map_wanted; /* locked by pager map */
|
|
static vaddr_t emergva;
|
|
static boolean_t emerginuse;
|
|
|
|
/*
|
|
* uvm_pager_init: init pagers (at boot time)
|
|
*/
|
|
|
|
void
|
|
uvm_pager_init()
|
|
{
|
|
int lcv;
|
|
|
|
/*
|
|
* init pager map
|
|
*/
|
|
|
|
pager_map = uvm_km_suballoc(kernel_map, &uvm.pager_sva, &uvm.pager_eva,
|
|
PAGER_MAP_SIZE, 0, FALSE, NULL);
|
|
simple_lock_init(&pager_map_wanted_lock);
|
|
pager_map_wanted = FALSE;
|
|
emergva = uvm_km_valloc(kernel_map, MAXBSIZE);
|
|
emerginuse = FALSE;
|
|
|
|
/*
|
|
* init ASYNC I/O queue
|
|
*/
|
|
|
|
TAILQ_INIT(&uvm.aio_done);
|
|
|
|
/*
|
|
* call pager init functions
|
|
*/
|
|
for (lcv = 0 ; lcv < sizeof(uvmpagerops)/sizeof(struct uvm_pagerops *);
|
|
lcv++) {
|
|
if (uvmpagerops[lcv]->pgo_init)
|
|
uvmpagerops[lcv]->pgo_init();
|
|
}
|
|
}
|
|
|
|
/*
|
|
* uvm_pagermapin: map pages into KVA (pager_map) for I/O that needs mappings
|
|
*
|
|
* we basically just map in a blank map entry to reserve the space in the
|
|
* map and then use pmap_enter() to put the mappings in by hand.
|
|
*/
|
|
|
|
vaddr_t
|
|
uvm_pagermapin(pps, npages, flags)
|
|
struct vm_page **pps;
|
|
int npages;
|
|
int flags;
|
|
{
|
|
vsize_t size;
|
|
vaddr_t kva;
|
|
vaddr_t cva;
|
|
struct vm_page *pp;
|
|
vm_prot_t prot;
|
|
UVMHIST_FUNC("uvm_pagermapin"); UVMHIST_CALLED(maphist);
|
|
|
|
UVMHIST_LOG(maphist,"(pps=0x%x, npages=%d)", pps, npages,0,0);
|
|
|
|
/*
|
|
* compute protection. outgoing I/O only needs read
|
|
* access to the page, whereas incoming needs read/write.
|
|
*/
|
|
|
|
prot = VM_PROT_READ;
|
|
if (flags & UVMPAGER_MAPIN_READ)
|
|
prot |= VM_PROT_WRITE;
|
|
|
|
ReStart:
|
|
size = npages << PAGE_SHIFT;
|
|
kva = 0; /* let system choose VA */
|
|
|
|
if (uvm_map(pager_map, &kva, size, NULL,
|
|
UVM_UNKNOWN_OFFSET, 0, UVM_FLAG_NOMERGE) != KERN_SUCCESS) {
|
|
if (curproc == uvm.pagedaemon_proc) {
|
|
simple_lock(&pager_map_wanted_lock);
|
|
if (emerginuse) {
|
|
UVM_UNLOCK_AND_WAIT(&emergva,
|
|
&pager_map_wanted_lock, FALSE,
|
|
"emergva", 0);
|
|
goto ReStart;
|
|
}
|
|
emerginuse = TRUE;
|
|
simple_unlock(&pager_map_wanted_lock);
|
|
kva = emergva;
|
|
KASSERT(npages <= MAXBSIZE >> PAGE_SHIFT);
|
|
goto enter;
|
|
}
|
|
if ((flags & UVMPAGER_MAPIN_WAITOK) == 0) {
|
|
UVMHIST_LOG(maphist,"<- NOWAIT failed", 0,0,0,0);
|
|
return(0);
|
|
}
|
|
simple_lock(&pager_map_wanted_lock);
|
|
pager_map_wanted = TRUE;
|
|
UVMHIST_LOG(maphist, " SLEEPING on pager_map",0,0,0,0);
|
|
UVM_UNLOCK_AND_WAIT(pager_map, &pager_map_wanted_lock, FALSE,
|
|
"pager_map", 0);
|
|
goto ReStart;
|
|
}
|
|
|
|
enter:
|
|
/* got it */
|
|
for (cva = kva ; size != 0 ; size -= PAGE_SIZE, cva += PAGE_SIZE) {
|
|
pp = *pps++;
|
|
KASSERT(pp);
|
|
KASSERT(pp->flags & PG_BUSY);
|
|
pmap_enter(vm_map_pmap(pager_map), cva, VM_PAGE_TO_PHYS(pp),
|
|
prot, PMAP_WIRED | ((pp->flags & PG_FAKE) ? prot :
|
|
VM_PROT_READ));
|
|
}
|
|
|
|
UVMHIST_LOG(maphist, "<- done (KVA=0x%x)", kva,0,0,0);
|
|
return(kva);
|
|
}
|
|
|
|
/*
|
|
* uvm_pagermapout: remove pager_map mapping
|
|
*
|
|
* we remove our mappings by hand and then remove the mapping (waking
|
|
* up anyone wanting space).
|
|
*/
|
|
|
|
void
|
|
uvm_pagermapout(kva, npages)
|
|
vaddr_t kva;
|
|
int npages;
|
|
{
|
|
vsize_t size = npages << PAGE_SHIFT;
|
|
vm_map_entry_t entries;
|
|
UVMHIST_FUNC("uvm_pagermapout"); UVMHIST_CALLED(maphist);
|
|
|
|
UVMHIST_LOG(maphist, " (kva=0x%x, npages=%d)", kva, npages,0,0);
|
|
|
|
/*
|
|
* duplicate uvm_unmap, but add in pager_map_wanted handling.
|
|
*/
|
|
|
|
if (kva == emergva) {
|
|
simple_lock(&pager_map_wanted_lock);
|
|
emerginuse = FALSE;
|
|
wakeup(&emergva);
|
|
simple_unlock(&pager_map_wanted_lock);
|
|
entries = NULL;
|
|
goto remove;
|
|
}
|
|
|
|
vm_map_lock(pager_map);
|
|
(void) uvm_unmap_remove(pager_map, kva, kva + size, &entries);
|
|
simple_lock(&pager_map_wanted_lock);
|
|
if (pager_map_wanted) {
|
|
pager_map_wanted = FALSE;
|
|
wakeup(pager_map);
|
|
}
|
|
simple_unlock(&pager_map_wanted_lock);
|
|
vm_map_unlock(pager_map);
|
|
remove:
|
|
pmap_remove(pmap_kernel(), kva, kva + (npages << PAGE_SHIFT));
|
|
if (entries)
|
|
uvm_unmap_detach(entries, 0);
|
|
|
|
UVMHIST_LOG(maphist,"<- done",0,0,0,0);
|
|
}
|
|
|
|
/*
|
|
* uvm_mk_pcluster
|
|
*
|
|
* generic "make 'pager put' cluster" function. a pager can either
|
|
* [1] set pgo_mk_pcluster to NULL (never cluster), [2] set it to this
|
|
* generic function, or [3] set it to a pager specific function.
|
|
*
|
|
* => caller must lock object _and_ pagequeues (since we need to look
|
|
* at active vs. inactive bits, etc.)
|
|
* => caller must make center page busy and write-protect it
|
|
* => we mark all cluster pages busy for the caller
|
|
* => the caller must unbusy all pages (and check wanted/released
|
|
* status if it drops the object lock)
|
|
* => flags:
|
|
* PGO_ALLPAGES: all pages in object are valid targets
|
|
* !PGO_ALLPAGES: use "lo" and "hi" to limit range of cluster
|
|
* PGO_DOACTCLUST: include active pages in cluster.
|
|
* NOTE: the caller should clear PG_CLEANCHK bits if PGO_DOACTCLUST.
|
|
* PG_CLEANCHK is only a hint, but clearing will help reduce
|
|
* the number of calls we make to the pmap layer.
|
|
*/
|
|
|
|
struct vm_page **
|
|
uvm_mk_pcluster(uobj, pps, npages, center, flags, mlo, mhi)
|
|
struct uvm_object *uobj; /* IN */
|
|
struct vm_page **pps, *center; /* IN/OUT, IN */
|
|
int *npages, flags; /* IN/OUT, IN */
|
|
voff_t mlo, mhi; /* IN (if !PGO_ALLPAGES) */
|
|
{
|
|
struct vm_page **ppsp, *pclust;
|
|
voff_t lo, hi, curoff;
|
|
int center_idx, forward, incr;
|
|
UVMHIST_FUNC("uvm_mk_pcluster"); UVMHIST_CALLED(maphist);
|
|
|
|
/*
|
|
* center page should already be busy and write protected. XXX:
|
|
* suppose page is wired? if we lock, then a process could
|
|
* fault/block on it. if we don't lock, a process could write the
|
|
* pages in the middle of an I/O. (consider an msync()). let's
|
|
* lock it for now (better to delay than corrupt data?).
|
|
*/
|
|
|
|
/*
|
|
* get cluster boundaries, check sanity, and apply our limits as well.
|
|
*/
|
|
|
|
uobj->pgops->pgo_cluster(uobj, center->offset, &lo, &hi);
|
|
if ((flags & PGO_ALLPAGES) == 0) {
|
|
if (lo < mlo)
|
|
lo = mlo;
|
|
if (hi > mhi)
|
|
hi = mhi;
|
|
}
|
|
if ((hi - lo) >> PAGE_SHIFT > *npages) { /* pps too small, bail out! */
|
|
pps[0] = center;
|
|
*npages = 1;
|
|
return(pps);
|
|
}
|
|
|
|
/*
|
|
* now determine the center and attempt to cluster around the
|
|
* edges
|
|
*/
|
|
|
|
center_idx = (center->offset - lo) >> PAGE_SHIFT;
|
|
pps[center_idx] = center; /* plug in the center page */
|
|
ppsp = &pps[center_idx];
|
|
*npages = 1;
|
|
|
|
/*
|
|
* attempt to cluster around the left [backward], and then
|
|
* the right side [forward].
|
|
*/
|
|
|
|
for (forward = 0 ; forward <= 1 ; forward++) {
|
|
incr = forward ? PAGE_SIZE : -PAGE_SIZE;
|
|
curoff = center->offset + incr;
|
|
for ( ;(forward == 0 && curoff >= lo) ||
|
|
(forward && curoff < hi);
|
|
curoff += incr) {
|
|
|
|
pclust = uvm_pagelookup(uobj, curoff); /* lookup page */
|
|
if (pclust == NULL) {
|
|
break; /* no page */
|
|
}
|
|
|
|
if ((flags & PGO_DOACTCLUST) == 0) {
|
|
/* dont want mapped pages at all */
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* get an up-to-date view of the "clean" bit.
|
|
* note this isn't 100% accurate, but it doesn't
|
|
* have to be. if it's not quite right, the
|
|
* worst that happens is we don't cluster as
|
|
* aggressively. we'll sync-it-for-sure before
|
|
* we free the page, and clean it if necessary.
|
|
*/
|
|
if ((pclust->flags & PG_CLEANCHK) == 0) {
|
|
if ((pclust->flags & (PG_CLEAN|PG_BUSY))
|
|
== PG_CLEAN &&
|
|
pmap_is_modified(pclust))
|
|
pclust->flags &= ~PG_CLEAN;
|
|
|
|
/* now checked */
|
|
pclust->flags |= PG_CLEANCHK;
|
|
}
|
|
|
|
/* is page available for cleaning and does it need it */
|
|
if ((pclust->flags & (PG_CLEAN|PG_BUSY)) != 0) {
|
|
break; /* page is already clean or is busy */
|
|
}
|
|
|
|
/* yes! enroll the page in our array */
|
|
pclust->flags |= PG_BUSY; /* busy! */
|
|
UVM_PAGE_OWN(pclust, "uvm_mk_pcluster");
|
|
|
|
/* XXX: protect wired page? see above comment. */
|
|
pmap_page_protect(pclust, VM_PROT_READ);
|
|
if (!forward) {
|
|
ppsp--; /* back up one page */
|
|
*ppsp = pclust;
|
|
} else {
|
|
/* move forward one page */
|
|
ppsp[*npages] = pclust;
|
|
}
|
|
(*npages)++;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* done! return the cluster array to the caller!!!
|
|
*/
|
|
|
|
UVMHIST_LOG(maphist, "<- done",0,0,0,0);
|
|
return(ppsp);
|
|
}
|
|
|
|
/*
|
|
* uvm_pager_put: high level pageout routine
|
|
*
|
|
* we want to pageout page "pg" to backing store, clustering if
|
|
* possible.
|
|
*
|
|
* => page queues must be locked by caller
|
|
* => if page is not swap-backed, then "uobj" points to the object
|
|
* backing it. this object should be locked by the caller.
|
|
* => if page is swap-backed, then "uobj" should be NULL.
|
|
* => "pg" should be PG_BUSY (by caller), and !PG_CLEAN
|
|
* for swap-backed memory, "pg" can be NULL if there is no page
|
|
* of interest [sometimes the case for the pagedaemon]
|
|
* => "ppsp_ptr" should point to an array of npages vm_page pointers
|
|
* for possible cluster building
|
|
* => flags (first two for non-swap-backed pages)
|
|
* PGO_ALLPAGES: all pages in uobj are valid targets
|
|
* PGO_DOACTCLUST: include "PQ_ACTIVE" pages as valid targets
|
|
* PGO_SYNCIO: wait for i/o to complete
|
|
* PGO_PDFREECLUST: pagedaemon: drop cluster on successful I/O
|
|
* => start/stop: if (uobj && !PGO_ALLPAGES) limit targets to this range
|
|
* if (!uobj) start is the (daddr_t) of the starting swapblk
|
|
* => return state:
|
|
* 1. we return the error code of the pageout
|
|
* 2. we return with the page queues unlocked
|
|
* 3. if (uobj != NULL) [!swap_backed] we return with
|
|
* uobj locked _only_ if PGO_PDFREECLUST is set
|
|
* AND result == 0 AND async. in all other cases
|
|
* we return with uobj unlocked. [this is a hack
|
|
* that allows the pagedaemon to save one lock/unlock
|
|
* pair in the !swap_backed case since we have to
|
|
* lock the uobj to drop the cluster anyway]
|
|
* 4. on errors we always drop the cluster. thus, if we return
|
|
* an error, then the caller only has to worry about
|
|
* un-busying the main page (not the cluster pages).
|
|
* 5. on success, if !PGO_PDFREECLUST, we return the cluster
|
|
* with all pages busy (caller must un-busy and check
|
|
* wanted/released flags).
|
|
*/
|
|
|
|
int
|
|
uvm_pager_put(uobj, pg, ppsp_ptr, npages, flags, start, stop)
|
|
struct uvm_object *uobj; /* IN */
|
|
struct vm_page *pg, ***ppsp_ptr;/* IN, IN/OUT */
|
|
int *npages; /* IN/OUT */
|
|
int flags; /* IN */
|
|
voff_t start, stop; /* IN, IN */
|
|
{
|
|
int result;
|
|
daddr_t swblk;
|
|
boolean_t async = (flags & PGO_SYNCIO) == 0;
|
|
struct vm_page **ppsp = *ppsp_ptr;
|
|
UVMHIST_FUNC("uvm_pager_put"); UVMHIST_CALLED(ubchist);
|
|
|
|
/*
|
|
* note that uobj is null if we are doing a swap-backed pageout.
|
|
* note that uobj is !null if we are doing normal object pageout.
|
|
* note that the page queues must be locked to cluster.
|
|
*/
|
|
|
|
if (uobj) { /* if !swap-backed */
|
|
|
|
/*
|
|
* attempt to build a cluster for pageout using its
|
|
* make-put-cluster function (if it has one).
|
|
*/
|
|
|
|
if (uobj->pgops->pgo_mk_pcluster) {
|
|
ppsp = uobj->pgops->pgo_mk_pcluster(uobj, ppsp,
|
|
npages, pg, flags, start, stop);
|
|
*ppsp_ptr = ppsp; /* update caller's pointer */
|
|
} else {
|
|
ppsp[0] = pg;
|
|
*npages = 1;
|
|
}
|
|
|
|
swblk = 0; /* XXX: keep gcc happy */
|
|
|
|
} else {
|
|
|
|
/*
|
|
* for swap-backed pageout, the caller (the pagedaemon) has
|
|
* already built the cluster for us. the starting swap
|
|
* block we are writing to has been passed in as "start."
|
|
* "pg" could be NULL if there is no page we are especially
|
|
* interested in (in which case the whole cluster gets dropped
|
|
* in the event of an error or a sync "done").
|
|
*/
|
|
swblk = (daddr_t) start;
|
|
/* ppsp and npages should be ok */
|
|
}
|
|
|
|
/* now that we've clustered we can unlock the page queues */
|
|
uvm_unlock_pageq();
|
|
|
|
/*
|
|
* now attempt the I/O. if we have a failure and we are
|
|
* clustered, we will drop the cluster and try again.
|
|
*/
|
|
|
|
ReTry:
|
|
if (uobj) {
|
|
/* object is locked */
|
|
result = uobj->pgops->pgo_put(uobj, ppsp, *npages, flags);
|
|
UVMHIST_LOG(ubchist, "put -> %d", result, 0,0,0);
|
|
/* object is now unlocked */
|
|
} else {
|
|
/* nothing locked */
|
|
result = uvm_swap_put(swblk, ppsp, *npages, flags);
|
|
/* nothing locked */
|
|
}
|
|
|
|
/*
|
|
* we have attempted the I/O.
|
|
*
|
|
* if the I/O was a success then:
|
|
* if !PGO_PDFREECLUST, we return the cluster to the
|
|
* caller (who must un-busy all pages)
|
|
* else we un-busy cluster pages for the pagedaemon
|
|
*
|
|
* if I/O is pending (async i/o) then we return the pending code.
|
|
* [in this case the async i/o done function must clean up when
|
|
* i/o is done...]
|
|
*/
|
|
|
|
if (result == 0) {
|
|
if (flags & PGO_PDFREECLUST && !async) {
|
|
|
|
/*
|
|
* drop cluster and relock object for sync i/o.
|
|
*/
|
|
|
|
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 #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 == EAGAIN) ? 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 == EAGAIN) {
|
|
|
|
/*
|
|
* 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++) {
|
|
|
|
/* skip "pg" or empty slot */
|
|
if (ppsp[lcv] == pg || ppsp[lcv] == NULL)
|
|
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
|
|
*/
|
|
|
|
saved_uobj = ppsp[lcv]->uobject;
|
|
obj_is_alive =
|
|
saved_uobj->pgops->pgo_releasepg(ppsp[lcv], NULL);
|
|
|
|
/* for normal objects, "pg" is still PG_BUSY by us,
|
|
* so obj can't die */
|
|
KASSERT(!uobj || obj_is_alive);
|
|
|
|
/* 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|PG_FAKE);
|
|
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);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* interrupt-context iodone handler for nested i/o bufs.
|
|
*
|
|
* => must be at splbio().
|
|
*/
|
|
|
|
void
|
|
uvm_aio_biodone1(bp)
|
|
struct buf *bp;
|
|
{
|
|
struct buf *mbp = bp->b_private;
|
|
|
|
KASSERT(mbp != bp);
|
|
if (bp->b_flags & B_ERROR) {
|
|
mbp->b_flags |= B_ERROR;
|
|
mbp->b_error = bp->b_error;
|
|
}
|
|
mbp->b_resid -= bp->b_bcount;
|
|
pool_put(&bufpool, bp);
|
|
if (mbp->b_resid == 0) {
|
|
biodone(mbp);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* interrupt-context iodone handler for single-buf i/os
|
|
* or the top-level buf of a nested-buf i/o.
|
|
*
|
|
* => must be at splbio().
|
|
*/
|
|
|
|
void
|
|
uvm_aio_biodone(bp)
|
|
struct buf *bp;
|
|
{
|
|
/* reset b_iodone for when this is a single-buf i/o. */
|
|
bp->b_iodone = uvm_aio_aiodone;
|
|
|
|
simple_lock(&uvm.aiodoned_lock); /* locks uvm.aio_done */
|
|
TAILQ_INSERT_TAIL(&uvm.aio_done, bp, b_freelist);
|
|
wakeup(&uvm.aiodoned);
|
|
simple_unlock(&uvm.aiodoned_lock);
|
|
}
|
|
|
|
/*
|
|
* uvm_aio_aiodone: do iodone processing for async i/os.
|
|
* this should be called in thread context, not interrupt context.
|
|
*/
|
|
|
|
void
|
|
uvm_aio_aiodone(bp)
|
|
struct buf *bp;
|
|
{
|
|
int npages = bp->b_bufsize >> PAGE_SHIFT;
|
|
struct vm_page *pg, *pgs[npages];
|
|
struct uvm_object *uobj;
|
|
int s, i, error;
|
|
boolean_t write, swap;
|
|
UVMHIST_FUNC("uvm_aio_aiodone"); UVMHIST_CALLED(ubchist);
|
|
UVMHIST_LOG(ubchist, "bp %p", bp, 0,0,0);
|
|
|
|
error = (bp->b_flags & B_ERROR) ? (bp->b_error ? bp->b_error : EIO) : 0;
|
|
write = (bp->b_flags & B_READ) == 0;
|
|
/* XXXUBC B_NOCACHE is for swap pager, should be done differently */
|
|
if (write && !(bp->b_flags & B_NOCACHE) && bioops.io_pageiodone) {
|
|
(*bioops.io_pageiodone)(bp);
|
|
}
|
|
|
|
uobj = NULL;
|
|
for (i = 0; i < npages; i++) {
|
|
pgs[i] = uvm_pageratop((vaddr_t)bp->b_data + (i << PAGE_SHIFT));
|
|
UVMHIST_LOG(ubchist, "pgs[%d] = %p", i, pgs[i],0,0);
|
|
}
|
|
uvm_pagermapout((vaddr_t)bp->b_data, npages);
|
|
for (i = 0; i < npages; i++) {
|
|
pg = pgs[i];
|
|
|
|
if (i == 0) {
|
|
swap = (pg->pqflags & PQ_SWAPBACKED) != 0;
|
|
if (!swap) {
|
|
uobj = pg->uobject;
|
|
simple_lock(&uobj->vmobjlock);
|
|
}
|
|
}
|
|
KASSERT(swap || pg->uobject == uobj);
|
|
if (swap) {
|
|
if (pg->pqflags & PQ_ANON) {
|
|
simple_lock(&pg->uanon->an_lock);
|
|
} else {
|
|
simple_lock(&pg->uobject->vmobjlock);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* if this is a read and we got an error, mark the pages
|
|
* PG_RELEASED so that uvm_page_unbusy() will free them.
|
|
*/
|
|
|
|
if (!write && error) {
|
|
pg->flags |= PG_RELEASED;
|
|
continue;
|
|
}
|
|
KASSERT(!write || (pgs[i]->flags & PG_FAKE) == 0);
|
|
|
|
/*
|
|
* if this is a read and the page is PG_FAKE,
|
|
* or this was a successful write,
|
|
* mark the page PG_CLEAN and not PG_FAKE.
|
|
*/
|
|
|
|
if ((pgs[i]->flags & PG_FAKE) || (write && error != ENOMEM)) {
|
|
pmap_clear_reference(pgs[i]);
|
|
pmap_clear_modify(pgs[i]);
|
|
pgs[i]->flags |= PG_CLEAN;
|
|
pgs[i]->flags &= ~PG_FAKE;
|
|
}
|
|
uvm_pageactivate(pg);
|
|
if (swap) {
|
|
if (pg->pqflags & PQ_ANON) {
|
|
simple_unlock(&pg->uanon->an_lock);
|
|
} else {
|
|
simple_unlock(&pg->uobject->vmobjlock);
|
|
}
|
|
}
|
|
}
|
|
uvm_page_unbusy(pgs, npages);
|
|
if (!swap) {
|
|
simple_unlock(&uobj->vmobjlock);
|
|
}
|
|
|
|
s = splbio();
|
|
if (write && (bp->b_flags & B_AGE) != 0) {
|
|
vwakeup(bp);
|
|
}
|
|
pool_put(&bufpool, bp);
|
|
splx(s);
|
|
}
|