freebsd-dev/sys/vm/vnode_pager.c
John Dyson eb2c768ebb When removing IN_RECURSE support during the Lite/2 merge, read/write
to/from mmaped regions was broken.  This commit fixes the breakage, and
uses the new Lite/2 locking mechanisms.
1997-03-08 04:33:47 +00:00

984 lines
22 KiB
C

/*
* Copyright (c) 1990 University of Utah.
* Copyright (c) 1991 The Regents of the University of California.
* All rights reserved.
* Copyright (c) 1993, 1994 John S. Dyson
* Copyright (c) 1995, David Greenman
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* 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 the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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: @(#)vnode_pager.c 7.5 (Berkeley) 4/20/91
* $Id: vnode_pager.c,v 1.69 1997/02/22 09:48:42 peter Exp $
*/
/*
* Page to/from files (vnodes).
*/
/*
* TODO:
* Implement VOP_GETPAGES/PUTPAGES interface for filesystems. Will
* greatly re-simplify the vnode_pager.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#include <sys/vnode.h>
#include <sys/uio.h>
#include <sys/mount.h>
#include <sys/buf.h>
#include <sys/vmmeter.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_prot.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pager.h>
#include <vm/vnode_pager.h>
#include <vm/vm_extern.h>
static vm_offset_t vnode_pager_addr __P((struct vnode *vp, vm_ooffset_t address,
int *run));
static void vnode_pager_iodone __P((struct buf *bp));
static int vnode_pager_input_smlfs __P((vm_object_t object, vm_page_t m));
static int vnode_pager_input_old __P((vm_object_t object, vm_page_t m));
static void vnode_pager_dealloc __P((vm_object_t));
static int vnode_pager_getpages __P((vm_object_t, vm_page_t *, int, int));
static int vnode_pager_putpages __P((vm_object_t, vm_page_t *, int, boolean_t, int *));
static boolean_t vnode_pager_haspage __P((vm_object_t, vm_pindex_t, int *, int *));
struct pagerops vnodepagerops = {
NULL,
vnode_pager_alloc,
vnode_pager_dealloc,
vnode_pager_getpages,
vnode_pager_putpages,
vnode_pager_haspage,
NULL
};
static int vnode_pager_leaf_getpages __P((vm_object_t object, vm_page_t *m,
int count, int reqpage));
static int vnode_pager_leaf_putpages __P((vm_object_t object, vm_page_t *m,
int count, boolean_t sync,
int *rtvals));
/*
* Allocate (or lookup) pager for a vnode.
* Handle is a vnode pointer.
*/
vm_object_t
vnode_pager_alloc(handle, size, prot, offset)
void *handle;
vm_size_t size;
vm_prot_t prot;
vm_ooffset_t offset;
{
vm_object_t object;
struct vnode *vp;
/*
* Pageout to vnode, no can do yet.
*/
if (handle == NULL)
return (NULL);
vp = (struct vnode *) handle;
/*
* Prevent race condition when allocating the object. This
* can happen with NFS vnodes since the nfsnode isn't locked.
*/
while (vp->v_flag & VOLOCK) {
vp->v_flag |= VOWANT;
tsleep(vp, PVM, "vnpobj", 0);
}
vp->v_flag |= VOLOCK;
/*
* If the object is being terminated, wait for it to
* go away.
*/
while (((object = vp->v_object) != NULL) &&
(object->flags & OBJ_DEAD)) {
tsleep(object, PVM, "vadead", 0);
}
if (object == NULL) {
/*
* And an object of the appropriate size
*/
object = vm_object_allocate(OBJT_VNODE, size);
if (vp->v_type == VREG)
object->flags = OBJ_CANPERSIST;
else
object->flags = 0;
if (vp->v_usecount == 0)
panic("vnode_pager_alloc: no vnode reference");
/*
* Hold a reference to the vnode and initialize object data.
*/
vp->v_usecount++;
object->un_pager.vnp.vnp_size = (vm_ooffset_t) size * PAGE_SIZE;
object->handle = handle;
vp->v_object = object;
} else {
/*
* vm_object_reference() will remove the object from the cache if
* found and gain a reference to the object.
*/
vm_object_reference(object);
}
if (vp->v_type == VREG)
vp->v_flag |= VVMIO;
vp->v_flag &= ~VOLOCK;
if (vp->v_flag & VOWANT) {
vp->v_flag &= ~VOWANT;
wakeup(vp);
}
return (object);
}
static void
vnode_pager_dealloc(object)
vm_object_t object;
{
register struct vnode *vp = object->handle;
if (vp == NULL)
panic("vnode_pager_dealloc: pager already dealloced");
if (object->paging_in_progress) {
int s = splbio();
while (object->paging_in_progress) {
object->flags |= OBJ_PIPWNT;
tsleep(object, PVM, "vnpdea", 0);
}
splx(s);
}
object->handle = NULL;
vp->v_object = NULL;
vp->v_flag &= ~(VTEXT | VVMIO);
vp->v_flag |= VAGE;
vrele(vp);
}
static boolean_t
vnode_pager_haspage(object, pindex, before, after)
vm_object_t object;
vm_pindex_t pindex;
int *before;
int *after;
{
struct vnode *vp = object->handle;
daddr_t bn;
int err;
daddr_t reqblock;
int poff;
int bsize;
int pagesperblock, blocksperpage;
/*
* If filesystem no longer mounted or offset beyond end of file we do
* not have the page.
*/
if ((vp->v_mount == NULL) ||
(IDX_TO_OFF(pindex) >= object->un_pager.vnp.vnp_size))
return FALSE;
bsize = vp->v_mount->mnt_stat.f_iosize;
pagesperblock = bsize / PAGE_SIZE;
blocksperpage = 0;
if (pagesperblock > 0) {
reqblock = pindex / pagesperblock;
} else {
blocksperpage = (PAGE_SIZE / bsize);
reqblock = pindex * blocksperpage;
}
err = VOP_BMAP(vp, reqblock, (struct vnode **) 0, &bn,
after, before);
if (err)
return TRUE;
if ( bn == -1)
return FALSE;
if (pagesperblock > 0) {
poff = pindex - (reqblock * pagesperblock);
if (before) {
*before *= pagesperblock;
*before += poff;
}
if (after) {
int numafter;
*after *= pagesperblock;
numafter = pagesperblock - (poff + 1);
if (IDX_TO_OFF(pindex + numafter) > object->un_pager.vnp.vnp_size) {
numafter = OFF_TO_IDX((object->un_pager.vnp.vnp_size - IDX_TO_OFF(pindex)));
}
*after += numafter;
}
} else {
if (before) {
*before /= blocksperpage;
}
if (after) {
*after /= blocksperpage;
}
}
return TRUE;
}
/*
* Lets the VM system know about a change in size for a file.
* We adjust our own internal size and flush any cached pages in
* the associated object that are affected by the size change.
*
* Note: this routine may be invoked as a result of a pager put
* operation (possibly at object termination time), so we must be careful.
*/
void
vnode_pager_setsize(vp, nsize)
struct vnode *vp;
vm_ooffset_t nsize;
{
vm_object_t object = vp->v_object;
if (object == NULL)
return;
/*
* Hasn't changed size
*/
if (nsize == object->un_pager.vnp.vnp_size)
return;
/*
* File has shrunk. Toss any cached pages beyond the new EOF.
*/
if (nsize < object->un_pager.vnp.vnp_size) {
vm_ooffset_t nsizerounded;
nsizerounded = IDX_TO_OFF(OFF_TO_IDX(nsize + PAGE_MASK));
if (nsizerounded < object->un_pager.vnp.vnp_size) {
vm_object_page_remove(object,
OFF_TO_IDX(nsize + PAGE_MASK),
OFF_TO_IDX(object->un_pager.vnp.vnp_size),
FALSE);
}
/*
* this gets rid of garbage at the end of a page that is now
* only partially backed by the vnode...
*/
if (nsize & PAGE_MASK) {
vm_offset_t kva;
vm_page_t m;
m = vm_page_lookup(object, OFF_TO_IDX(nsize));
if (m) {
kva = vm_pager_map_page(m);
bzero((caddr_t) kva + (nsize & PAGE_MASK),
(int) (round_page(nsize) - nsize));
vm_pager_unmap_page(kva);
}
}
}
object->un_pager.vnp.vnp_size = nsize;
object->size = OFF_TO_IDX(nsize + PAGE_MASK);
}
void
vnode_pager_umount(mp)
register struct mount *mp;
{
struct proc *p = curproc; /* XXX */
struct vnode *vp, *nvp;
loop:
for (vp = mp->mnt_vnodelist.lh_first; vp != NULL; vp = nvp) {
/*
* Vnode can be reclaimed by getnewvnode() while we
* traverse the list.
*/
if (vp->v_mount != mp)
goto loop;
/*
* Save the next pointer now since uncaching may terminate the
* object and render vnode invalid
*/
nvp = vp->v_mntvnodes.le_next;
if (vp->v_object != NULL) {
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
vnode_pager_uncache(vp, p);
VOP_UNLOCK(vp, 0, p);
}
}
}
/*
* Remove vnode associated object from the object cache.
* This routine must be called with the vnode locked.
*
* XXX unlock the vnode.
* We must do this since uncaching the object may result in its
* destruction which may initiate paging activity which may necessitate
* re-locking the vnode.
*/
void
vnode_pager_uncache(vp, p)
struct vnode *vp;
struct proc *p;
{
vm_object_t object;
/*
* Not a mapped vnode
*/
object = vp->v_object;
if (object == NULL)
return;
vm_object_reference(object);
/*
* XXX We really should handle locking on
* VBLK devices...
*/
if (vp->v_type != VBLK)
VOP_UNLOCK(vp, 0, p);
pager_cache(object, FALSE);
if (vp->v_type != VBLK)
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
return;
}
void
vnode_pager_freepage(m)
vm_page_t m;
{
PAGE_WAKEUP(m);
vm_page_free(m);
}
/*
* calculate the linear (byte) disk address of specified virtual
* file address
*/
static vm_offset_t
vnode_pager_addr(vp, address, run)
struct vnode *vp;
vm_ooffset_t address;
int *run;
{
int rtaddress;
int bsize;
daddr_t block;
struct vnode *rtvp;
int err;
daddr_t vblock;
int voffset;
if ((int) address < 0)
return -1;
if (vp->v_mount == NULL)
return -1;
bsize = vp->v_mount->mnt_stat.f_iosize;
vblock = address / bsize;
voffset = address % bsize;
err = VOP_BMAP(vp, vblock, &rtvp, &block, run, NULL);
if (err || (block == -1))
rtaddress = -1;
else {
rtaddress = block + voffset / DEV_BSIZE;
if( run) {
*run += 1;
*run *= bsize/PAGE_SIZE;
*run -= voffset/PAGE_SIZE;
}
}
return rtaddress;
}
/*
* interrupt routine for I/O completion
*/
static void
vnode_pager_iodone(bp)
struct buf *bp;
{
bp->b_flags |= B_DONE;
wakeup(bp);
}
/*
* small block file system vnode pager input
*/
static int
vnode_pager_input_smlfs(object, m)
vm_object_t object;
vm_page_t m;
{
int i;
int s;
struct vnode *dp, *vp;
struct buf *bp;
vm_offset_t kva;
int fileaddr;
vm_offset_t bsize;
int error = 0;
vp = object->handle;
if (vp->v_mount == NULL)
return VM_PAGER_BAD;
bsize = vp->v_mount->mnt_stat.f_iosize;
VOP_BMAP(vp, 0, &dp, 0, NULL, NULL);
kva = vm_pager_map_page(m);
for (i = 0; i < PAGE_SIZE / bsize; i++) {
if ((vm_page_bits(IDX_TO_OFF(m->pindex) + i * bsize, bsize) & m->valid))
continue;
fileaddr = vnode_pager_addr(vp,
IDX_TO_OFF(m->pindex) + i * bsize, (int *)0);
if (fileaddr != -1) {
bp = getpbuf();
/* build a minimal buffer header */
bp->b_flags = B_BUSY | B_READ | B_CALL;
bp->b_iodone = vnode_pager_iodone;
bp->b_proc = curproc;
bp->b_rcred = bp->b_wcred = bp->b_proc->p_ucred;
if (bp->b_rcred != NOCRED)
crhold(bp->b_rcred);
if (bp->b_wcred != NOCRED)
crhold(bp->b_wcred);
bp->b_un.b_addr = (caddr_t) kva + i * bsize;
bp->b_blkno = fileaddr;
pbgetvp(dp, bp);
bp->b_bcount = bsize;
bp->b_bufsize = bsize;
/* do the input */
VOP_STRATEGY(bp);
/* we definitely need to be at splbio here */
s = splbio();
while ((bp->b_flags & B_DONE) == 0) {
tsleep(bp, PVM, "vnsrd", 0);
}
splx(s);
if ((bp->b_flags & B_ERROR) != 0)
error = EIO;
/*
* free the buffer header back to the swap buffer pool
*/
relpbuf(bp);
if (error)
break;
vm_page_set_validclean(m, (i * bsize) & PAGE_MASK, bsize);
} else {
vm_page_set_validclean(m, (i * bsize) & PAGE_MASK, bsize);
bzero((caddr_t) kva + i * bsize, bsize);
}
}
vm_pager_unmap_page(kva);
pmap_clear_modify(VM_PAGE_TO_PHYS(m));
m->flags &= ~PG_ZERO;
if (error) {
return VM_PAGER_ERROR;
}
return VM_PAGER_OK;
}
/*
* old style vnode pager output routine
*/
static int
vnode_pager_input_old(object, m)
vm_object_t object;
vm_page_t m;
{
struct uio auio;
struct iovec aiov;
int error;
int size;
vm_offset_t kva;
error = 0;
/*
* Return failure if beyond current EOF
*/
if (IDX_TO_OFF(m->pindex) >= object->un_pager.vnp.vnp_size) {
return VM_PAGER_BAD;
} else {
size = PAGE_SIZE;
if (IDX_TO_OFF(m->pindex) + size > object->un_pager.vnp.vnp_size)
size = object->un_pager.vnp.vnp_size - IDX_TO_OFF(m->pindex);
/*
* Allocate a kernel virtual address and initialize so that
* we can use VOP_READ/WRITE routines.
*/
kva = vm_pager_map_page(m);
aiov.iov_base = (caddr_t) kva;
aiov.iov_len = size;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = IDX_TO_OFF(m->pindex);
auio.uio_segflg = UIO_SYSSPACE;
auio.uio_rw = UIO_READ;
auio.uio_resid = size;
auio.uio_procp = (struct proc *) 0;
error = VOP_READ(object->handle, &auio, 0, curproc->p_ucred);
if (!error) {
register int count = size - auio.uio_resid;
if (count == 0)
error = EINVAL;
else if (count != PAGE_SIZE)
bzero((caddr_t) kva + count, PAGE_SIZE - count);
}
vm_pager_unmap_page(kva);
}
pmap_clear_modify(VM_PAGE_TO_PHYS(m));
m->dirty = 0;
m->flags &= ~PG_ZERO;
return error ? VM_PAGER_ERROR : VM_PAGER_OK;
}
/*
* generic vnode pager input routine
*/
static int
vnode_pager_getpages(object, m, count, reqpage)
vm_object_t object;
vm_page_t *m;
int count;
int reqpage;
{
int rtval;
struct vnode *vp;
if (object->flags & OBJ_VNODE_GONE)
return VM_PAGER_ERROR;
vp = object->handle;
rtval = VOP_GETPAGES(vp, m, count*PAGE_SIZE, reqpage, 0);
if (rtval == EOPNOTSUPP)
return vnode_pager_leaf_getpages(object, m, count, reqpage);
else
return rtval;
}
static int
vnode_pager_leaf_getpages(object, m, count, reqpage)
vm_object_t object;
vm_page_t *m;
int count;
int reqpage;
{
vm_offset_t kva;
off_t foff;
int i, size, bsize, first, firstaddr;
struct vnode *dp, *vp;
int runpg;
int runend;
struct buf *bp;
int s;
int error = 0;
vp = object->handle;
if (vp->v_mount == NULL)
return VM_PAGER_BAD;
bsize = vp->v_mount->mnt_stat.f_iosize;
/* get the UNDERLYING device for the file with VOP_BMAP() */
/*
* originally, we did not check for an error return value -- assuming
* an fs always has a bmap entry point -- that assumption is wrong!!!
*/
foff = IDX_TO_OFF(m[reqpage]->pindex);
/*
* if we can't bmap, use old VOP code
*/
if (VOP_BMAP(vp, 0, &dp, 0, NULL, NULL)) {
for (i = 0; i < count; i++) {
if (i != reqpage) {
vnode_pager_freepage(m[i]);
}
}
cnt.v_vnodein++;
cnt.v_vnodepgsin++;
return vnode_pager_input_old(object, m[reqpage]);
/*
* if the blocksize is smaller than a page size, then use
* special small filesystem code. NFS sometimes has a small
* blocksize, but it can handle large reads itself.
*/
} else if ((PAGE_SIZE / bsize) > 1 &&
(vp->v_mount->mnt_stat.f_type != MOUNT_NFS)) {
for (i = 0; i < count; i++) {
if (i != reqpage) {
vnode_pager_freepage(m[i]);
}
}
cnt.v_vnodein++;
cnt.v_vnodepgsin++;
return vnode_pager_input_smlfs(object, m[reqpage]);
}
/*
* if ANY DEV_BSIZE blocks are valid on a large filesystem block
* then, the entire page is valid --
*/
if (m[reqpage]->valid) {
m[reqpage]->valid = VM_PAGE_BITS_ALL;
for (i = 0; i < count; i++) {
if (i != reqpage)
vnode_pager_freepage(m[i]);
}
return VM_PAGER_OK;
}
/*
* here on direct device I/O
*/
firstaddr = -1;
/*
* calculate the run that includes the required page
*/
for(first = 0, i = 0; i < count; i = runend) {
firstaddr = vnode_pager_addr(vp,
IDX_TO_OFF(m[i]->pindex), &runpg);
if (firstaddr == -1) {
if (i == reqpage && foff < object->un_pager.vnp.vnp_size) {
panic("vnode_pager_putpages: unexpected missing page: firstaddr: %d, foff: %ld, vnp_size: %d",
firstaddr, foff, object->un_pager.vnp.vnp_size);
}
vnode_pager_freepage(m[i]);
runend = i + 1;
first = runend;
continue;
}
runend = i + runpg;
if (runend <= reqpage) {
int j;
for (j = i; j < runend; j++) {
vnode_pager_freepage(m[j]);
}
} else {
if (runpg < (count - first)) {
for (i = first + runpg; i < count; i++)
vnode_pager_freepage(m[i]);
count = first + runpg;
}
break;
}
first = runend;
}
/*
* the first and last page have been calculated now, move input pages
* to be zero based...
*/
if (first != 0) {
for (i = first; i < count; i++) {
m[i - first] = m[i];
}
count -= first;
reqpage -= first;
}
/*
* calculate the file virtual address for the transfer
*/
foff = IDX_TO_OFF(m[0]->pindex);
/*
* calculate the size of the transfer
*/
size = count * PAGE_SIZE;
if ((foff + size) > object->un_pager.vnp.vnp_size)
size = object->un_pager.vnp.vnp_size - foff;
/*
* round up physical size for real devices
*/
if (dp->v_type == VBLK || dp->v_type == VCHR)
size = (size + DEV_BSIZE - 1) & ~(DEV_BSIZE - 1);
bp = getpbuf();
kva = (vm_offset_t) bp->b_data;
/*
* and map the pages to be read into the kva
*/
pmap_qenter(kva, m, count);
/* build a minimal buffer header */
bp->b_flags = B_BUSY | B_READ | B_CALL;
bp->b_iodone = vnode_pager_iodone;
/* B_PHYS is not set, but it is nice to fill this in */
bp->b_proc = curproc;
bp->b_rcred = bp->b_wcred = bp->b_proc->p_ucred;
if (bp->b_rcred != NOCRED)
crhold(bp->b_rcred);
if (bp->b_wcred != NOCRED)
crhold(bp->b_wcred);
bp->b_blkno = firstaddr;
pbgetvp(dp, bp);
bp->b_bcount = size;
bp->b_bufsize = size;
cnt.v_vnodein++;
cnt.v_vnodepgsin += count;
/* do the input */
VOP_STRATEGY(bp);
s = splbio();
/* we definitely need to be at splbio here */
while ((bp->b_flags & B_DONE) == 0) {
tsleep(bp, PVM, "vnread", 0);
}
splx(s);
if ((bp->b_flags & B_ERROR) != 0)
error = EIO;
if (!error) {
if (size != count * PAGE_SIZE)
bzero((caddr_t) kva + size, PAGE_SIZE * count - size);
}
pmap_qremove(kva, count);
/*
* free the buffer header back to the swap buffer pool
*/
relpbuf(bp);
for (i = 0; i < count; i++) {
pmap_clear_modify(VM_PAGE_TO_PHYS(m[i]));
m[i]->dirty = 0;
m[i]->valid = VM_PAGE_BITS_ALL;
m[i]->flags &= ~PG_ZERO;
if (i != reqpage) {
/*
* whether or not to leave the page activated is up in
* the air, but we should put the page on a page queue
* somewhere. (it already is in the object). Result:
* It appears that emperical results show that
* deactivating pages is best.
*/
/*
* just in case someone was asking for this page we
* now tell them that it is ok to use
*/
if (!error) {
vm_page_deactivate(m[i]);
PAGE_WAKEUP(m[i]);
} else {
vnode_pager_freepage(m[i]);
}
}
}
if (error) {
printf("vnode_pager_getpages: I/O read error\n");
}
return (error ? VM_PAGER_ERROR : VM_PAGER_OK);
}
static int
vnode_pager_putpages(object, m, count, sync, rtvals)
vm_object_t object;
vm_page_t *m;
int count;
boolean_t sync;
int *rtvals;
{
int rtval;
struct vnode *vp;
if (object->flags & OBJ_VNODE_GONE)
return VM_PAGER_ERROR;
vp = object->handle;
rtval = VOP_PUTPAGES(vp, m, count*PAGE_SIZE, sync, rtvals, 0);
if (rtval == EOPNOTSUPP)
return vnode_pager_leaf_putpages(object, m, count, sync, rtvals);
else
return rtval;
}
/*
* generic vnode pager output routine
*/
static int
vnode_pager_leaf_putpages(object, m, count, sync, rtvals)
vm_object_t object;
vm_page_t *m;
int count;
boolean_t sync;
int *rtvals;
{
int i;
struct vnode *vp;
int maxsize, ncount;
vm_ooffset_t poffset;
struct uio auio;
struct iovec aiov;
int error;
vp = object->handle;;
for (i = 0; i < count; i++)
rtvals[i] = VM_PAGER_AGAIN;
if ((int) m[0]->pindex < 0) {
printf("vnode_pager_putpages: attempt to write meta-data!!! -- 0x%x(%x)\n", m[0]->pindex, m[0]->dirty);
rtvals[0] = VM_PAGER_BAD;
return VM_PAGER_BAD;
}
maxsize = count * PAGE_SIZE;
ncount = count;
poffset = IDX_TO_OFF(m[0]->pindex);
if (maxsize + poffset > object->un_pager.vnp.vnp_size) {
if (object->un_pager.vnp.vnp_size > poffset)
maxsize = object->un_pager.vnp.vnp_size - poffset;
else
maxsize = 0;
ncount = btoc(maxsize);
if (ncount < count) {
for (i = ncount; i < count; i++) {
rtvals[i] = VM_PAGER_BAD;
}
#ifdef BOGUS
if (ncount == 0) {
printf("vnode_pager_putpages: write past end of file: %d, %lu\n",
poffset,
(unsigned long) object->un_pager.vnp.vnp_size);
return rtvals[0];
}
#endif
}
}
for (i = 0; i < count; i++) {
m[i]->busy++;
m[i]->flags &= ~PG_BUSY;
}
aiov.iov_base = (caddr_t) 0;
aiov.iov_len = maxsize;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = poffset;
auio.uio_segflg = UIO_NOCOPY;
auio.uio_rw = UIO_WRITE;
auio.uio_resid = maxsize;
auio.uio_procp = (struct proc *) 0;
error = VOP_WRITE(vp, &auio, IO_VMIO|(sync?IO_SYNC:0), curproc->p_ucred);
cnt.v_vnodeout++;
cnt.v_vnodepgsout += ncount;
if (error) {
printf("vnode_pager_putpages: I/O error %d\n", error);
}
if (auio.uio_resid) {
printf("vnode_pager_putpages: residual I/O %d at %ld\n",
auio.uio_resid, m[0]->pindex);
}
for (i = 0; i < count; i++) {
m[i]->busy--;
if (i < ncount) {
rtvals[i] = VM_PAGER_OK;
}
if ((m[i]->busy == 0) && (m[i]->flags & PG_WANTED))
wakeup(m[i]);
}
return rtvals[0];
}
struct vnode *
vnode_pager_lock(object)
vm_object_t object;
{
struct proc *p = curproc; /* XXX */
for (; object != NULL; object = object->backing_object) {
if (object->type != OBJT_VNODE)
continue;
vn_lock(object->handle, LK_EXCLUSIVE | LK_RETRY | LK_CANRECURSE, p);
return object->handle;
}
return NULL;
}