2 * Copyright (c) 1990 University of Utah.
3 * Copyright (c) 1991 The Regents of the University of California.
5 * Copyright (c) 1993, 1994 John S. Dyson
6 * Copyright (c) 1995, David Greenman
8 * This code is derived from software contributed to Berkeley by
9 * the Systems Programming Group of the University of Utah Computer
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. All advertising materials mentioning features or use of this software
21 * must display the following acknowledgement:
22 * This product includes software developed by the University of
23 * California, Berkeley and its contributors.
24 * 4. Neither the name of the University nor the names of its contributors
25 * may be used to endorse or promote products derived from this software
26 * without specific prior written permission.
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40 * from: @(#)vnode_pager.c 7.5 (Berkeley) 4/20/91
41 * $FreeBSD: src/sys/vm/vnode_pager.c,v 1.116.2.7 2002/12/31 09:34:51 dillon Exp $
42 * $DragonFly: src/sys/vm/vnode_pager.c,v 1.21 2006/02/17 19:18:08 dillon Exp $
46 * Page to/from files (vnodes).
51 * Implement VOP_GETPAGES/PUTPAGES interface for filesystems. Will
52 * greatly re-simplify the vnode_pager.
55 #include <sys/param.h>
56 #include <sys/systm.h>
57 #include <sys/kernel.h>
59 #include <sys/vnode.h>
60 #include <sys/mount.h>
62 #include <sys/vmmeter.h>
64 #include <sys/sfbuf.h>
65 #include <sys/thread2.h>
68 #include <vm/vm_object.h>
69 #include <vm/vm_page.h>
70 #include <vm/vm_pager.h>
71 #include <vm/vm_map.h>
72 #include <vm/vnode_pager.h>
73 #include <vm/vm_extern.h>
75 static vm_offset_t vnode_pager_addr (struct vnode *vp, vm_ooffset_t address,
77 static void vnode_pager_iodone (struct bio *bio);
78 static int vnode_pager_input_smlfs (vm_object_t object, vm_page_t m);
79 static int vnode_pager_input_old (vm_object_t object, vm_page_t m);
80 static void vnode_pager_dealloc (vm_object_t);
81 static int vnode_pager_getpages (vm_object_t, vm_page_t *, int, int);
82 static void vnode_pager_putpages (vm_object_t, vm_page_t *, int, boolean_t, int *);
83 static boolean_t vnode_pager_haspage (vm_object_t, vm_pindex_t, int *, int *);
85 struct pagerops vnodepagerops = {
95 int vnode_pbuf_freecnt = -1; /* start out unlimited */
98 * Allocate (or lookup) pager for a vnode.
99 * Handle is a vnode pointer.
102 vnode_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot,
109 * Pageout to vnode, no can do yet.
115 * XXX hack - This initialization should be put somewhere else.
117 if (vnode_pbuf_freecnt < 0) {
118 vnode_pbuf_freecnt = nswbuf / 2 + 1;
121 vp = (struct vnode *) handle;
124 * Prevent race condition when allocating the object. This
125 * can happen with NFS vnodes since the nfsnode isn't locked.
127 while (vp->v_flag & VOLOCK) {
128 vp->v_flag |= VOWANT;
129 tsleep(vp, 0, "vnpobj", 0);
131 vp->v_flag |= VOLOCK;
134 * If the object is being terminated, wait for it to
137 while (((object = vp->v_object) != NULL) &&
138 (object->flags & OBJ_DEAD)) {
139 tsleep(object, 0, "vadead", 0);
142 if (vp->v_usecount == 0)
143 panic("vnode_pager_alloc: no vnode reference");
145 if (object == NULL) {
147 * And an object of the appropriate size
149 object = vm_object_allocate(OBJT_VNODE, OFF_TO_IDX(round_page(size)));
152 object->un_pager.vnp.vnp_size = size;
154 object->handle = handle;
155 vp->v_object = object;
162 vp->v_flag &= ~VOLOCK;
163 if (vp->v_flag & VOWANT) {
164 vp->v_flag &= ~VOWANT;
171 vnode_pager_dealloc(vm_object_t object)
173 struct vnode *vp = object->handle;
176 panic("vnode_pager_dealloc: pager already dealloced");
178 vm_object_pip_wait(object, "vnpdea");
180 object->handle = NULL;
181 object->type = OBJT_DEAD;
183 vp->v_flag &= ~(VTEXT | VOBJBUF);
187 vnode_pager_haspage(vm_object_t object, vm_pindex_t pindex, int *before,
190 struct vnode *vp = object->handle;
196 int pagesperblock, blocksperpage;
199 * If no vp or vp is doomed or marked transparent to VM, we do not
202 if ((vp == NULL) || (vp->v_flag & VRECLAIMED))
206 * If filesystem no longer mounted or offset beyond end of file we do
209 if ((vp->v_mount == NULL) ||
210 (IDX_TO_OFF(pindex) >= object->un_pager.vnp.vnp_size))
213 bsize = vp->v_mount->mnt_stat.f_iosize;
214 pagesperblock = bsize / PAGE_SIZE;
216 if (pagesperblock > 0) {
217 reqblock = pindex / pagesperblock;
219 blocksperpage = (PAGE_SIZE / bsize);
220 reqblock = pindex * blocksperpage;
222 err = VOP_BMAP(vp, reqblock, (struct vnode **) 0, &bn,
228 if (pagesperblock > 0) {
229 poff = pindex - (reqblock * pagesperblock);
231 *before *= pagesperblock;
236 *after *= pagesperblock;
237 numafter = pagesperblock - (poff + 1);
238 if (IDX_TO_OFF(pindex + numafter) > object->un_pager.vnp.vnp_size) {
239 numafter = OFF_TO_IDX((object->un_pager.vnp.vnp_size - IDX_TO_OFF(pindex)));
245 *before /= blocksperpage;
249 *after /= blocksperpage;
256 * Lets the VM system know about a change in size for a file.
257 * We adjust our own internal size and flush any cached pages in
258 * the associated object that are affected by the size change.
260 * Note: this routine may be invoked as a result of a pager put
261 * operation (possibly at object termination time), so we must be careful.
264 vnode_pager_setsize(struct vnode *vp, vm_ooffset_t nsize)
266 vm_pindex_t nobjsize;
267 vm_object_t object = vp->v_object;
273 * Hasn't changed size
275 if (nsize == object->un_pager.vnp.vnp_size)
278 nobjsize = OFF_TO_IDX(nsize + PAGE_MASK);
281 * File has shrunk. Toss any cached pages beyond the new EOF.
283 if (nsize < object->un_pager.vnp.vnp_size) {
284 vm_freeze_copyopts(object, OFF_TO_IDX(nsize), object->size);
285 if (nobjsize < object->size) {
286 vm_object_page_remove(object, nobjsize, object->size,
290 * This gets rid of garbage at the end of a page that is now
291 * only partially backed by the vnode. Since we are setting
292 * the entire page valid & clean after we are done we have
293 * to be sure that the portion of the page within the file
294 * bounds is already valid. If it isn't then making it
295 * valid would create a corrupt block.
297 if (nsize & PAGE_MASK) {
301 m = vm_page_lookup(object, OFF_TO_IDX(nsize));
303 int base = (int)nsize & PAGE_MASK;
304 int size = PAGE_SIZE - base;
308 * Clear out partial-page garbage in case
309 * the page has been mapped.
311 sf = sf_buf_alloc(m, SFB_CPUPRIVATE);
312 kva = sf_buf_kva(sf);
313 bzero((caddr_t)kva + base, size);
317 * XXX work around SMP data integrity race
318 * by unmapping the page from user processes.
319 * The garbage we just cleared may be mapped
320 * to a user process running on another cpu
321 * and this code is not running through normal
322 * I/O channels which handle SMP issues for
323 * us, so unmap page to synchronize all cpus.
325 * XXX should vm_pager_unmap_page() have
328 vm_page_protect(m, VM_PROT_NONE);
331 * Clear out partial-page dirty bits. This
332 * has the side effect of setting the valid
333 * bits, but that is ok. There are a bunch
334 * of places in the VM system where we expected
335 * m->dirty == VM_PAGE_BITS_ALL. The file EOF
336 * case is one of them. If the page is still
337 * partially dirty, make it fully dirty.
339 * note that we do not clear out the valid
340 * bits. This would prevent bogus_page
341 * replacement from working properly.
343 vm_page_set_validclean(m, base, size);
345 m->dirty = VM_PAGE_BITS_ALL;
349 object->un_pager.vnp.vnp_size = nsize;
350 object->size = nobjsize;
354 vnode_pager_freepage(vm_page_t m)
360 * calculate the linear (byte) disk address of specified virtual
364 vnode_pager_addr(struct vnode *vp, vm_ooffset_t address, int *run)
377 if (vp->v_mount == NULL)
380 bsize = vp->v_mount->mnt_stat.f_iosize;
381 vblock = address / bsize;
382 voffset = address % bsize;
384 err = VOP_BMAP(vp, vblock, &rtvp, &block, run, NULL);
386 if (err || (block == -1))
389 rtaddress = block + voffset / DEV_BSIZE;
392 *run *= bsize/PAGE_SIZE;
393 *run -= voffset/PAGE_SIZE;
401 * interrupt routine for I/O completion
404 vnode_pager_iodone(struct bio *bio)
406 struct buf *bp = bio->bio_buf;
408 bp->b_flags |= B_DONE;
413 * small block file system vnode pager input
416 vnode_pager_input_smlfs(vm_object_t object, vm_page_t m)
419 struct vnode *dp, *vp;
428 if (vp->v_mount == NULL)
431 bsize = vp->v_mount->mnt_stat.f_iosize;
434 VOP_BMAP(vp, 0, &dp, 0, NULL, NULL);
436 sf = sf_buf_alloc(m, 0);
437 kva = sf_buf_kva(sf);
439 for (i = 0; i < PAGE_SIZE / bsize; i++) {
440 vm_ooffset_t address;
442 if (vm_page_bits(i * bsize, bsize) & m->valid)
445 address = IDX_TO_OFF(m->pindex) + i * bsize;
446 if (address >= object->un_pager.vnp.vnp_size) {
449 fileaddr = vnode_pager_addr(vp, address, NULL);
451 if (fileaddr != -1) {
452 bp = getpbuf(&vnode_pbuf_freecnt);
454 /* build a minimal buffer header */
455 bp->b_flags = B_READ;
456 bp->b_data = (caddr_t) kva + i * bsize;
457 bp->b_bio1.bio_done = vnode_pager_iodone;
458 bp->b_bio1.bio_blkno = fileaddr;
460 bp->b_bcount = bsize;
461 bp->b_bufsize = bsize;
462 bp->b_runningbufspace = bp->b_bufsize;
463 runningbufspace += bp->b_runningbufspace;
466 vn_strategy(dp, &bp->b_bio1);
468 /* we definitely need to be at splvm here */
471 while ((bp->b_flags & B_DONE) == 0) {
472 tsleep(bp, 0, "vnsrd", 0);
475 if ((bp->b_flags & B_ERROR) != 0)
479 * free the buffer header back to the swap buffer pool
481 relpbuf(bp, &vnode_pbuf_freecnt);
485 vm_page_set_validclean(m, (i * bsize) & PAGE_MASK, bsize);
487 vm_page_set_validclean(m, (i * bsize) & PAGE_MASK, bsize);
488 bzero((caddr_t) kva + i * bsize, bsize);
492 pmap_clear_modify(m);
493 vm_page_flag_clear(m, PG_ZERO);
495 return VM_PAGER_ERROR;
503 * old style vnode pager output routine
506 vnode_pager_input_old(vm_object_t object, vm_page_t m)
518 * Return failure if beyond current EOF
520 if (IDX_TO_OFF(m->pindex) >= object->un_pager.vnp.vnp_size) {
524 if (IDX_TO_OFF(m->pindex) + size > object->un_pager.vnp.vnp_size)
525 size = object->un_pager.vnp.vnp_size - IDX_TO_OFF(m->pindex);
528 * Allocate a kernel virtual address and initialize so that
529 * we can use VOP_READ/WRITE routines.
531 sf = sf_buf_alloc(m, 0);
532 kva = sf_buf_kva(sf);
534 aiov.iov_base = (caddr_t) kva;
536 auio.uio_iov = &aiov;
538 auio.uio_offset = IDX_TO_OFF(m->pindex);
539 auio.uio_segflg = UIO_SYSSPACE;
540 auio.uio_rw = UIO_READ;
541 auio.uio_resid = size;
542 auio.uio_td = curthread;
544 error = VOP_READ(((struct vnode *)object->handle),
545 &auio, 0, proc0.p_ucred);
547 int count = size - auio.uio_resid;
551 else if (count != PAGE_SIZE)
552 bzero((caddr_t) kva + count, PAGE_SIZE - count);
556 pmap_clear_modify(m);
558 vm_page_flag_clear(m, PG_ZERO);
560 m->valid = VM_PAGE_BITS_ALL;
561 return error ? VM_PAGER_ERROR : VM_PAGER_OK;
565 * generic vnode pager input routine
569 * EOPNOTSUPP is no longer legal. For local media VFS's that do not
570 * implement their own VOP_GETPAGES, their VOP_GETPAGES should call to
571 * vnode_pager_generic_getpages() to implement the previous behaviour.
573 * All other FS's should use the bypass to get to the local media
574 * backing vp's VOP_GETPAGES.
577 vnode_pager_getpages(vm_object_t object, vm_page_t *m, int count, int reqpage)
581 int bytes = count * PAGE_SIZE;
585 * XXX temporary diagnostic message to help track stale FS code,
586 * Returning EOPNOTSUPP from here may make things unhappy.
588 rtval = VOP_GETPAGES(vp, m, bytes, reqpage, 0);
589 if (rtval == EOPNOTSUPP) {
590 printf("vnode_pager: *** WARNING *** stale FS getpages\n");
591 rtval = vnode_pager_generic_getpages( vp, m, bytes, reqpage);
598 * This is now called from local media FS's to operate against their
599 * own vnodes if they fail to implement VOP_GETPAGES.
602 vnode_pager_generic_getpages(struct vnode *vp, vm_page_t *m, int bytecount,
607 off_t foff, tfoff, nextoff;
608 int i, size, bsize, first, firstaddr;
616 object = vp->v_object;
617 count = bytecount / PAGE_SIZE;
619 if (vp->v_mount == NULL)
622 bsize = vp->v_mount->mnt_stat.f_iosize;
624 /* get the UNDERLYING device for the file with VOP_BMAP() */
627 * originally, we did not check for an error return value -- assuming
628 * an fs always has a bmap entry point -- that assumption is wrong!!!
630 foff = IDX_TO_OFF(m[reqpage]->pindex);
633 * if we can't bmap, use old VOP code
635 if (VOP_BMAP(vp, 0, &dp, 0, NULL, NULL)) {
636 for (i = 0; i < count; i++) {
638 vnode_pager_freepage(m[i]);
641 mycpu->gd_cnt.v_vnodein++;
642 mycpu->gd_cnt.v_vnodepgsin++;
643 return vnode_pager_input_old(object, m[reqpage]);
646 * if the blocksize is smaller than a page size, then use
647 * special small filesystem code. NFS sometimes has a small
648 * blocksize, but it can handle large reads itself.
650 } else if ((PAGE_SIZE / bsize) > 1 &&
651 (vp->v_mount->mnt_stat.f_type != nfs_mount_type)) {
652 for (i = 0; i < count; i++) {
654 vnode_pager_freepage(m[i]);
657 mycpu->gd_cnt.v_vnodein++;
658 mycpu->gd_cnt.v_vnodepgsin++;
659 return vnode_pager_input_smlfs(object, m[reqpage]);
663 * If we have a completely valid page available to us, we can
664 * clean up and return. Otherwise we have to re-read the
667 * Note that this does not work with NFS, so NFS has its own
668 * getpages routine. The problem is that NFS can have partially
669 * valid pages associated with the buffer cache due to the piecemeal
670 * write support. If we were to fall through and re-read the media
671 * as we do here, dirty data could be lost.
674 if (m[reqpage]->valid == VM_PAGE_BITS_ALL) {
675 for (i = 0; i < count; i++) {
677 vnode_pager_freepage(m[i]);
681 m[reqpage]->valid = 0;
684 * here on direct device I/O
689 * calculate the run that includes the required page
691 for(first = 0, i = 0; i < count; i = runend) {
692 firstaddr = vnode_pager_addr(vp,
693 IDX_TO_OFF(m[i]->pindex), &runpg);
694 if (firstaddr == -1) {
695 if (i == reqpage && foff < object->un_pager.vnp.vnp_size) {
696 /* XXX no %qd in kernel. */
697 panic("vnode_pager_getpages: unexpected missing page: firstaddr: %d, foff: 0x%lx%08lx, vnp_size: 0x%lx%08lx",
698 firstaddr, (u_long)(foff >> 32),
699 (u_long)(u_int32_t)foff,
701 (object->un_pager.vnp.vnp_size >> 32),
703 object->un_pager.vnp.vnp_size);
705 vnode_pager_freepage(m[i]);
711 if (runend <= reqpage) {
713 for (j = i; j < runend; j++) {
714 vnode_pager_freepage(m[j]);
717 if (runpg < (count - first)) {
718 for (i = first + runpg; i < count; i++)
719 vnode_pager_freepage(m[i]);
720 count = first + runpg;
728 * the first and last page have been calculated now, move input pages
729 * to be zero based...
732 for (i = first; i < count; i++) {
740 * calculate the file virtual address for the transfer
742 foff = IDX_TO_OFF(m[0]->pindex);
745 * calculate the size of the transfer
747 size = count * PAGE_SIZE;
748 if ((foff + size) > object->un_pager.vnp.vnp_size)
749 size = object->un_pager.vnp.vnp_size - foff;
752 * round up physical size for real devices.
754 if (dp->v_type == VBLK || dp->v_type == VCHR) {
755 int secmask = dp->v_rdev->si_bsize_phys - 1;
756 KASSERT(secmask < PAGE_SIZE, ("vnode_pager_generic_getpages: sector size %d too large\n", secmask + 1));
757 size = (size + secmask) & ~secmask;
760 bp = getpbuf(&vnode_pbuf_freecnt);
761 kva = (vm_offset_t) bp->b_data;
764 * and map the pages to be read into the kva
766 pmap_qenter(kva, m, count);
768 /* build a minimal buffer header */
769 bp->b_flags = B_READ;
770 bp->b_bio1.bio_done = vnode_pager_iodone;
771 bp->b_bio1.bio_blkno = firstaddr;
774 bp->b_bufsize = size;
775 bp->b_runningbufspace = bp->b_bufsize;
776 runningbufspace += bp->b_runningbufspace;
778 mycpu->gd_cnt.v_vnodein++;
779 mycpu->gd_cnt.v_vnodepgsin += count;
782 vn_strategy(dp, &bp->b_bio1);
785 /* we definitely need to be at splvm here */
787 while ((bp->b_flags & B_DONE) == 0) {
788 tsleep(bp, 0, "vnread", 0);
791 if ((bp->b_flags & B_ERROR) != 0)
795 if (size != count * PAGE_SIZE)
796 bzero((caddr_t) kva + size, PAGE_SIZE * count - size);
798 pmap_qremove(kva, count);
801 * free the buffer header back to the swap buffer pool
803 relpbuf(bp, &vnode_pbuf_freecnt);
805 for (i = 0, tfoff = foff; i < count; i++, tfoff = nextoff) {
808 nextoff = tfoff + PAGE_SIZE;
811 if (nextoff <= object->un_pager.vnp.vnp_size) {
813 * Read filled up entire page.
815 mt->valid = VM_PAGE_BITS_ALL;
816 vm_page_undirty(mt); /* should be an assert? XXX */
817 pmap_clear_modify(mt);
820 * Read did not fill up entire page. Since this
821 * is getpages, the page may be mapped, so we have
822 * to zero the invalid portions of the page even
823 * though we aren't setting them valid.
825 * Currently we do not set the entire page valid,
826 * we just try to clear the piece that we couldn't
829 vm_page_set_validclean(mt, 0,
830 object->un_pager.vnp.vnp_size - tfoff);
831 /* handled by vm_fault now */
832 /* vm_page_zero_invalid(mt, FALSE); */
835 vm_page_flag_clear(mt, PG_ZERO);
839 * whether or not to leave the page activated is up in
840 * the air, but we should put the page on a page queue
841 * somewhere. (it already is in the object). Result:
842 * It appears that empirical results show that
843 * deactivating pages is best.
847 * just in case someone was asking for this page we
848 * now tell them that it is ok to use
851 if (mt->flags & PG_WANTED)
852 vm_page_activate(mt);
854 vm_page_deactivate(mt);
857 vnode_pager_freepage(mt);
862 printf("vnode_pager_getpages: I/O read error\n");
864 return (error ? VM_PAGER_ERROR : VM_PAGER_OK);
868 * EOPNOTSUPP is no longer legal. For local media VFS's that do not
869 * implement their own VOP_PUTPAGES, their VOP_PUTPAGES should call to
870 * vnode_pager_generic_putpages() to implement the previous behaviour.
872 * All other FS's should use the bypass to get to the local media
873 * backing vp's VOP_PUTPAGES.
876 vnode_pager_putpages(vm_object_t object, vm_page_t *m, int count,
877 boolean_t sync, int *rtvals)
881 int bytes = count * PAGE_SIZE;
884 * Force synchronous operation if we are extremely low on memory
885 * to prevent a low-memory deadlock. VOP operations often need to
886 * allocate more memory to initiate the I/O ( i.e. do a BMAP
887 * operation ). The swapper handles the case by limiting the amount
888 * of asynchronous I/O, but that sort of solution doesn't scale well
889 * for the vnode pager without a lot of work.
891 * Also, the backing vnode's iodone routine may not wake the pageout
892 * daemon up. This should be probably be addressed XXX.
895 if ((vmstats.v_free_count + vmstats.v_cache_count) < vmstats.v_pageout_free_min)
899 * Call device-specific putpages function
903 rtval = VOP_PUTPAGES(vp, m, bytes, sync, rtvals, 0);
904 if (rtval == EOPNOTSUPP) {
905 printf("vnode_pager: *** WARNING *** stale FS putpages\n");
906 rtval = vnode_pager_generic_putpages( vp, m, bytes, sync, rtvals);
912 * This is now called from local media FS's to operate against their
913 * own vnodes if they fail to implement VOP_PUTPAGES.
915 * This is typically called indirectly via the pageout daemon and
916 * clustering has already typically occured, so in general we ask the
917 * underlying filesystem to write the data out asynchronously rather
921 vnode_pager_generic_putpages(struct vnode *vp, vm_page_t *m, int bytecount,
922 int flags, int *rtvals)
929 vm_ooffset_t poffset;
935 object = vp->v_object;
936 count = bytecount / PAGE_SIZE;
938 for (i = 0; i < count; i++)
939 rtvals[i] = VM_PAGER_AGAIN;
941 if ((int) m[0]->pindex < 0) {
942 printf("vnode_pager_putpages: attempt to write meta-data!!! -- 0x%lx(%x)\n",
943 (long)m[0]->pindex, m[0]->dirty);
944 rtvals[0] = VM_PAGER_BAD;
948 maxsize = count * PAGE_SIZE;
951 poffset = IDX_TO_OFF(m[0]->pindex);
954 * If the page-aligned write is larger then the actual file we
955 * have to invalidate pages occuring beyond the file EOF. However,
956 * there is an edge case where a file may not be page-aligned where
957 * the last page is partially invalid. In this case the filesystem
958 * may not properly clear the dirty bits for the entire page (which
959 * could be VM_PAGE_BITS_ALL due to the page having been mmap()d).
960 * With the page locked we are free to fix-up the dirty bits here.
962 * We do not under any circumstances truncate the valid bits, as
963 * this will screw up bogus page replacement.
965 if (maxsize + poffset > object->un_pager.vnp.vnp_size) {
966 if (object->un_pager.vnp.vnp_size > poffset) {
969 maxsize = object->un_pager.vnp.vnp_size - poffset;
970 ncount = btoc(maxsize);
971 if ((pgoff = (int)maxsize & PAGE_MASK) != 0) {
972 vm_page_clear_dirty(m[ncount - 1], pgoff,
979 if (ncount < count) {
980 for (i = ncount; i < count; i++) {
981 rtvals[i] = VM_PAGER_BAD;
987 * pageouts are already clustered, use IO_ASYNC to force a bawrite()
988 * rather then a bdwrite() to prevent paging I/O from saturating
989 * the buffer cache. Dummy-up the sequential heuristic to cause
990 * large ranges to cluster. If neither IO_SYNC or IO_ASYNC is set,
991 * the system decides how to cluster.
994 if (flags & (VM_PAGER_PUT_SYNC | VM_PAGER_PUT_INVAL))
996 else if ((flags & VM_PAGER_CLUSTER_OK) == 0)
998 ioflags |= (flags & VM_PAGER_PUT_INVAL) ? IO_INVAL: 0;
999 ioflags |= IO_SEQMAX << IO_SEQSHIFT;
1001 aiov.iov_base = (caddr_t) 0;
1002 aiov.iov_len = maxsize;
1003 auio.uio_iov = &aiov;
1004 auio.uio_iovcnt = 1;
1005 auio.uio_offset = poffset;
1006 auio.uio_segflg = UIO_NOCOPY;
1007 auio.uio_rw = UIO_WRITE;
1008 auio.uio_resid = maxsize;
1010 error = VOP_WRITE(vp, &auio, ioflags, proc0.p_ucred);
1011 mycpu->gd_cnt.v_vnodeout++;
1012 mycpu->gd_cnt.v_vnodepgsout += ncount;
1015 printf("vnode_pager_putpages: I/O error %d\n", error);
1017 if (auio.uio_resid) {
1018 printf("vnode_pager_putpages: residual I/O %d at %lu\n",
1019 auio.uio_resid, (u_long)m[0]->pindex);
1021 for (i = 0; i < ncount; i++) {
1022 rtvals[i] = VM_PAGER_OK;
1028 vnode_pager_lock(vm_object_t object)
1030 struct thread *td = curthread; /* XXX */
1033 for (; object != NULL; object = object->backing_object) {
1034 if (object->type != OBJT_VNODE)
1036 if (object->flags & OBJ_DEAD)
1040 struct vnode *vp = object->handle;
1041 error = vget(vp, LK_NOPAUSE | LK_SHARED |
1042 LK_RETRY | LK_CANRECURSE, td);
1044 if (object->handle != vp) {
1050 if ((object->flags & OBJ_DEAD) ||
1051 (object->type != OBJT_VNODE)) {
1054 printf("vnode_pager_lock: vp %p error %d lockstatus %d, retrying\n", vp, error, lockstatus(&vp->v_lock, td));
1055 tsleep(object->handle, 0, "vnpgrl", hz);