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freebsd/sys/vm/vnode_pager.c
John Dyson 9fea9a6f5b The whole issue of not support VOP_LOCK for VBLK devices should be
rethought.  This fixes YET another problem with unmounting filesystems.
The root cause is not fixed here, but at least the problem has gone
away.
1996-09-10 05:28:23 +00:00

972 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 1.63 1996/08/21 21:56:23 dyson 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;
/*
* 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 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) {
VOP_LOCK(vp);
vnode_pager_uncache(vp);
VOP_UNLOCK(vp);
}
}
}
/*
* 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)
struct vnode *vp;
{
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);
pager_cache(object, FALSE);
if (vp->v_type != VBLK)
VOP_LOCK(vp);
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;
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;
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;
{
for (; object != NULL; object = object->backing_object) {
if (object->type != OBJT_VNODE)
continue;
VOP_LOCK(object->handle);
return object->handle;
}
return NULL;
}