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ffs_vnops.c revision 1.16.2.2
      1 /*	$NetBSD: ffs_vnops.c,v 1.16.2.2 1998/11/16 08:25:38 chs Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1982, 1986, 1989, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  *
     35  *	@(#)ffs_vnops.c	8.15 (Berkeley) 5/14/95
     36  */
     37 
     38 #if defined(_KERNEL) && !defined(_LKM)
     39 #include "opt_uvm.h"
     40 #endif
     41 
     42 #include <sys/param.h>
     43 #include <sys/systm.h>
     44 #include <sys/resourcevar.h>
     45 #include <sys/kernel.h>
     46 #include <sys/file.h>
     47 #include <sys/stat.h>
     48 #include <sys/buf.h>
     49 #include <sys/proc.h>
     50 #include <sys/conf.h>
     51 #include <sys/mount.h>
     52 #include <sys/vnode.h>
     53 #include <sys/malloc.h>
     54 #include <sys/pool.h>
     55 #include <sys/signalvar.h>
     56 
     57 #include <vm/vm.h>
     58 
     59 #if defined(UVM)
     60 #include <uvm/uvm_extern.h>
     61 #endif
     62 
     63 #include <miscfs/fifofs/fifo.h>
     64 #include <miscfs/genfs/genfs.h>
     65 #include <miscfs/specfs/specdev.h>
     66 
     67 #include <ufs/ufs/quota.h>
     68 #include <ufs/ufs/inode.h>
     69 #include <ufs/ufs/dir.h>
     70 #include <ufs/ufs/ufs_extern.h>
     71 #include <ufs/ufs/ufsmount.h>
     72 
     73 #include <ufs/ffs/fs.h>
     74 #include <ufs/ffs/ffs_extern.h>
     75 
     76 /* Global vfs data structures for ufs. */
     77 int (**ffs_vnodeop_p) __P((void *));
     78 struct vnodeopv_entry_desc ffs_vnodeop_entries[] = {
     79 	{ &vop_default_desc, vn_default_error },
     80 	{ &vop_lookup_desc, ufs_lookup },		/* lookup */
     81 	{ &vop_create_desc, ufs_create },		/* create */
     82 	{ &vop_whiteout_desc, ufs_whiteout },		/* whiteout */
     83 	{ &vop_mknod_desc, ufs_mknod },			/* mknod */
     84 	{ &vop_open_desc, ufs_open },			/* open */
     85 	{ &vop_close_desc, ufs_close },			/* close */
     86 	{ &vop_access_desc, ufs_access },		/* access */
     87 	{ &vop_getattr_desc, ufs_getattr },		/* getattr */
     88 	{ &vop_setattr_desc, ufs_setattr },		/* setattr */
     89 	{ &vop_read_desc, ffs_read },			/* read */
     90 	{ &vop_write_desc, ffs_write },			/* write */
     91 	{ &vop_lease_desc, ufs_lease_check },		/* lease */
     92 	{ &vop_ioctl_desc, ufs_ioctl },			/* ioctl */
     93 	{ &vop_poll_desc, ufs_poll },			/* poll */
     94 	{ &vop_revoke_desc, ufs_revoke },		/* revoke */
     95 	{ &vop_mmap_desc, ufs_mmap },			/* mmap */
     96 	{ &vop_fsync_desc, ffs_fsync },			/* fsync */
     97 	{ &vop_seek_desc, ufs_seek },			/* seek */
     98 	{ &vop_remove_desc, ufs_remove },		/* remove */
     99 	{ &vop_link_desc, ufs_link },			/* link */
    100 	{ &vop_rename_desc, ufs_rename },		/* rename */
    101 	{ &vop_mkdir_desc, ufs_mkdir },			/* mkdir */
    102 	{ &vop_rmdir_desc, ufs_rmdir },			/* rmdir */
    103 	{ &vop_symlink_desc, ufs_symlink },		/* symlink */
    104 	{ &vop_readdir_desc, ufs_readdir },		/* readdir */
    105 	{ &vop_readlink_desc, ufs_readlink },		/* readlink */
    106 	{ &vop_abortop_desc, ufs_abortop },		/* abortop */
    107 	{ &vop_inactive_desc, ufs_inactive },		/* inactive */
    108 	{ &vop_reclaim_desc, ffs_reclaim },		/* reclaim */
    109 	{ &vop_lock_desc, ufs_lock },			/* lock */
    110 	{ &vop_unlock_desc, ufs_unlock },		/* unlock */
    111 	{ &vop_bmap_desc, ufs_bmap },			/* bmap */
    112 	{ &vop_strategy_desc, ufs_strategy },		/* strategy */
    113 	{ &vop_print_desc, ufs_print },			/* print */
    114 	{ &vop_islocked_desc, ufs_islocked },		/* islocked */
    115 	{ &vop_pathconf_desc, ufs_pathconf },		/* pathconf */
    116 	{ &vop_advlock_desc, ufs_advlock },		/* advlock */
    117 	{ &vop_blkatoff_desc, ffs_blkatoff },		/* blkatoff */
    118 	{ &vop_valloc_desc, ffs_valloc },		/* valloc */
    119 	{ &vop_reallocblks_desc, ffs_reallocblks },	/* reallocblks */
    120 	{ &vop_vfree_desc, ffs_vfree },			/* vfree */
    121 	{ &vop_truncate_desc, ffs_truncate },		/* truncate */
    122 	{ &vop_update_desc, ffs_update },		/* update */
    123 	{ &vop_bwrite_desc, vn_bwrite },		/* bwrite */
    124 #ifdef UBC
    125 	{ &vop_getpages_desc, ffs_getpages },		/* getpages */
    126 	{ &vop_putpages_desc, ffs_putpages },		/* putpages */
    127 #endif
    128 	{ NULL, NULL }
    129 };
    130 struct vnodeopv_desc ffs_vnodeop_opv_desc =
    131 	{ &ffs_vnodeop_p, ffs_vnodeop_entries };
    132 
    133 int (**ffs_specop_p) __P((void *));
    134 struct vnodeopv_entry_desc ffs_specop_entries[] = {
    135 	{ &vop_default_desc, vn_default_error },
    136 	{ &vop_lookup_desc, spec_lookup },		/* lookup */
    137 	{ &vop_create_desc, spec_create },		/* create */
    138 	{ &vop_mknod_desc, spec_mknod },		/* mknod */
    139 	{ &vop_open_desc, spec_open },			/* open */
    140 	{ &vop_close_desc, ufsspec_close },		/* close */
    141 	{ &vop_access_desc, ufs_access },		/* access */
    142 	{ &vop_getattr_desc, ufs_getattr },		/* getattr */
    143 	{ &vop_setattr_desc, ufs_setattr },		/* setattr */
    144 	{ &vop_read_desc, ufsspec_read },		/* read */
    145 	{ &vop_write_desc, ufsspec_write },		/* write */
    146 	{ &vop_lease_desc, spec_lease_check },		/* lease */
    147 	{ &vop_ioctl_desc, spec_ioctl },		/* ioctl */
    148 	{ &vop_poll_desc, spec_poll },			/* poll */
    149 	{ &vop_revoke_desc, spec_revoke },		/* revoke */
    150 	{ &vop_mmap_desc, spec_mmap },			/* mmap */
    151 	{ &vop_fsync_desc, ffs_fsync },			/* fsync */
    152 	{ &vop_seek_desc, spec_seek },			/* seek */
    153 	{ &vop_remove_desc, spec_remove },		/* remove */
    154 	{ &vop_link_desc, spec_link },			/* link */
    155 	{ &vop_rename_desc, spec_rename },		/* rename */
    156 	{ &vop_mkdir_desc, spec_mkdir },		/* mkdir */
    157 	{ &vop_rmdir_desc, spec_rmdir },		/* rmdir */
    158 	{ &vop_symlink_desc, spec_symlink },		/* symlink */
    159 	{ &vop_readdir_desc, spec_readdir },		/* readdir */
    160 	{ &vop_readlink_desc, spec_readlink },		/* readlink */
    161 	{ &vop_abortop_desc, spec_abortop },		/* abortop */
    162 	{ &vop_inactive_desc, ufs_inactive },		/* inactive */
    163 	{ &vop_reclaim_desc, ffs_reclaim },		/* reclaim */
    164 	{ &vop_lock_desc, ufs_lock },			/* lock */
    165 	{ &vop_unlock_desc, ufs_unlock },		/* unlock */
    166 	{ &vop_bmap_desc, spec_bmap },			/* bmap */
    167 	{ &vop_strategy_desc, spec_strategy },		/* strategy */
    168 	{ &vop_print_desc, ufs_print },			/* print */
    169 	{ &vop_islocked_desc, ufs_islocked },		/* islocked */
    170 	{ &vop_pathconf_desc, spec_pathconf },		/* pathconf */
    171 	{ &vop_advlock_desc, spec_advlock },		/* advlock */
    172 	{ &vop_blkatoff_desc, spec_blkatoff },		/* blkatoff */
    173 	{ &vop_valloc_desc, spec_valloc },		/* valloc */
    174 	{ &vop_reallocblks_desc, spec_reallocblks },	/* reallocblks */
    175 	{ &vop_vfree_desc, ffs_vfree },			/* vfree */
    176 	{ &vop_truncate_desc, spec_truncate },		/* truncate */
    177 	{ &vop_update_desc, ffs_update },		/* update */
    178 	{ &vop_bwrite_desc, vn_bwrite },		/* bwrite */
    179 	{ (struct vnodeop_desc*)NULL, (int(*) __P((void *)))NULL }
    180 };
    181 struct vnodeopv_desc ffs_specop_opv_desc =
    182 	{ &ffs_specop_p, ffs_specop_entries };
    183 
    184 int (**ffs_fifoop_p) __P((void *));
    185 struct vnodeopv_entry_desc ffs_fifoop_entries[] = {
    186 	{ &vop_default_desc, vn_default_error },
    187 	{ &vop_lookup_desc, fifo_lookup },		/* lookup */
    188 	{ &vop_create_desc, fifo_create },		/* create */
    189 	{ &vop_mknod_desc, fifo_mknod },		/* mknod */
    190 	{ &vop_open_desc, fifo_open },			/* open */
    191 	{ &vop_close_desc, ufsfifo_close },		/* close */
    192 	{ &vop_access_desc, ufs_access },		/* access */
    193 	{ &vop_getattr_desc, ufs_getattr },		/* getattr */
    194 	{ &vop_setattr_desc, ufs_setattr },		/* setattr */
    195 	{ &vop_read_desc, ufsfifo_read },		/* read */
    196 	{ &vop_write_desc, ufsfifo_write },		/* write */
    197 	{ &vop_lease_desc, fifo_lease_check },		/* lease */
    198 	{ &vop_ioctl_desc, fifo_ioctl },		/* ioctl */
    199 	{ &vop_poll_desc, fifo_poll },			/* poll */
    200 	{ &vop_revoke_desc, fifo_revoke },		/* revoke */
    201 	{ &vop_mmap_desc, fifo_mmap },			/* mmap */
    202 	{ &vop_fsync_desc, ffs_fsync },			/* fsync */
    203 	{ &vop_seek_desc, fifo_seek },			/* seek */
    204 	{ &vop_remove_desc, fifo_remove },		/* remove */
    205 	{ &vop_link_desc, fifo_link },			/* link */
    206 	{ &vop_rename_desc, fifo_rename },		/* rename */
    207 	{ &vop_mkdir_desc, fifo_mkdir },		/* mkdir */
    208 	{ &vop_rmdir_desc, fifo_rmdir },		/* rmdir */
    209 	{ &vop_symlink_desc, fifo_symlink },		/* symlink */
    210 	{ &vop_readdir_desc, fifo_readdir },		/* readdir */
    211 	{ &vop_readlink_desc, fifo_readlink },		/* readlink */
    212 	{ &vop_abortop_desc, fifo_abortop },		/* abortop */
    213 	{ &vop_inactive_desc, ufs_inactive },		/* inactive */
    214 	{ &vop_reclaim_desc, ffs_reclaim },		/* reclaim */
    215 	{ &vop_lock_desc, ufs_lock },			/* lock */
    216 	{ &vop_unlock_desc, ufs_unlock },		/* unlock */
    217 	{ &vop_bmap_desc, fifo_bmap },			/* bmap */
    218 	{ &vop_strategy_desc, fifo_strategy },		/* strategy */
    219 	{ &vop_print_desc, ufs_print },			/* print */
    220 	{ &vop_islocked_desc, ufs_islocked },		/* islocked */
    221 	{ &vop_pathconf_desc, fifo_pathconf },		/* pathconf */
    222 	{ &vop_advlock_desc, fifo_advlock },		/* advlock */
    223 	{ &vop_blkatoff_desc, fifo_blkatoff },		/* blkatoff */
    224 	{ &vop_valloc_desc, fifo_valloc },		/* valloc */
    225 	{ &vop_reallocblks_desc, fifo_reallocblks },	/* reallocblks */
    226 	{ &vop_vfree_desc, ffs_vfree },			/* vfree */
    227 	{ &vop_truncate_desc, fifo_truncate },		/* truncate */
    228 	{ &vop_update_desc, ffs_update },		/* update */
    229 	{ &vop_bwrite_desc, vn_bwrite },		/* bwrite */
    230 	{ (struct vnodeop_desc*)NULL, (int(*) __P((void *)))NULL }
    231 };
    232 struct vnodeopv_desc ffs_fifoop_opv_desc =
    233 	{ &ffs_fifoop_p, ffs_fifoop_entries };
    234 
    235 int doclusterread = 1;
    236 int doclusterwrite = 1;
    237 
    238 #include <ufs/ufs/ufs_readwrite.c>
    239 
    240 /*
    241  * Reclaim an inode so that it can be used for other purposes.
    242  */
    243 int
    244 ffs_reclaim(v)
    245 	void *v;
    246 {
    247 	struct vop_reclaim_args /* {
    248 		struct vnode *a_vp;
    249 		struct proc *a_p;
    250 	} */ *ap = v;
    251 	register struct vnode *vp = ap->a_vp;
    252 	int error;
    253 
    254 	if ((error = ufs_reclaim(vp, ap->a_p)) != 0)
    255 		return (error);
    256 
    257 	/*
    258 	 * XXX MFS ends up here, too, to free an inode.  Should we create
    259 	 * XXX a separate pool for MFS inodes?
    260 	 */
    261 	pool_put(&ffs_inode_pool, vp->v_data);
    262 	vp->v_data = NULL;
    263 	return (0);
    264 }
    265 
    266 
    267 #ifdef UBC
    268 #include "opt_uvmhist.h"
    269 #include <uvm/uvm.h>
    270 UVMHIST_DECL(ubchist); /* XXX */
    271 
    272 int
    273 ffs_getpages(v)
    274 	void *v;
    275 {
    276 	struct vop_getpages_args /* {
    277 		struct vnode *a_vp;
    278 		vaddr_t a_offset;
    279 		vm_page_t *a_m;
    280 		int *a_count;
    281 		int a_centeridx;
    282 		vm_prot_t a_access_type;
    283 		int a_advice;
    284 		int a_flags;
    285 	} */ *ap = v;
    286 
    287 	int error;
    288 	struct uio uio;
    289 	struct iovec iov;
    290 	vm_page_t m;
    291 	vaddr_t kva;
    292 	struct buf tmpbuf, *bp;
    293 	struct vnode *vp = ap->a_vp;
    294 	struct uvm_object *uobj = &vp->v_uvm.u_obj;
    295 	struct inode *ip = VTOI(vp);
    296 	struct fs *fs = ip->i_fs;
    297 	UVMHIST_FUNC("ffs_getpages"); UVMHIST_CALLED(ubchist);
    298 
    299 	/* XXX don't deal with PGO_LOCKED yet */
    300 	if (ap->a_flags & PGO_LOCKED) {
    301 		*ap->a_count = 0;
    302 		return 0;
    303 	}
    304 
    305 	/* vnode is VOP_LOCKed, uobj is locked */
    306 
    307 	/* XXX for now, just do one page at a time */
    308 	if (*ap->a_count != 1) {
    309 	    panic("ffs_getpages: one at a time, please\n");
    310 	}
    311 
    312 #ifdef DIAGNOSTIC
    313 	if (ap->a_centeridx < 0 || ap->a_centeridx > *ap->a_count) {
    314 		panic("ffs_getpages: centeridx %d out of range",
    315 		      ap->a_centeridx);
    316 	}
    317 #endif
    318 
    319 	uvn_findpage(uobj, ap->a_offset, ap->a_m);
    320 	m = ap->a_m[ap->a_centeridx];
    321 
    322 	simple_unlock(&uobj->vmobjlock);
    323 
    324 	if ((m->flags & PG_FAKE) == 0) {
    325 		UVMHIST_LOG(ubchist, "page was valid",0,0,0,0);
    326 		return 0;
    327 	}
    328 
    329 	kva = uvm_pagermapin(ap->a_m, *ap->a_count, NULL, M_WAITOK);
    330 	if (kva == 0) {
    331 	    printf("uvm_pagermapin failed\n");
    332 	    return EAGAIN;
    333 	}
    334 
    335 	uio.uio_iov = &iov;
    336 	iov.iov_len = 0;
    337 
    338 	bp = &tmpbuf;
    339 	bzero(bp, sizeof *bp);
    340 
    341 	bp->b_bufsize = PAGE_SIZE;
    342 	bp->b_data = (void *)kva;
    343 	bp->b_lblkno = lblkno(fs, m->offset);
    344 	bp->b_bcount = bp->b_lblkno < 0 ? PAGE_SIZE :
    345 		min(PAGE_SIZE, fragroundup(fs, vp->v_uvm.u_size - m->offset));
    346 	bp->b_vp = vp;
    347 	bp->b_flags = B_BUSY|B_READ;
    348 
    349 UVMHIST_LOG(ubchist, "bp %p vp %p blkno 0x%x",
    350        bp, vp, bp->b_lblkno, 0);
    351 
    352 	error = VOP_BMAP(vp, bp->b_lblkno, NULL, &bp->b_blkno, NULL);
    353 	if (error) {
    354 UVMHIST_LOG(ubchist, "VOP_BMAP error %d", error,0,0,0);
    355 		return (error);
    356 	}
    357 UVMHIST_LOG(ubchist, "VOP_BMAP gave 0x%x", bp->b_blkno,0,0,0);
    358 	if ((long)bp->b_blkno == -1) {
    359 		/*
    360 		 * XXX pre-allocate blocks here someday?
    361 		 */
    362 		bzero((void *)kva, PAGE_SIZE);
    363 		uvm_pagermapout(kva, *ap->a_count);
    364 		return 0;
    365 	}
    366 
    367 	/* adjust physical blkno for partial blocks */
    368 	bp->b_blkno += (m->offset - lblktosize(fs, bp->b_lblkno)) >> DEV_BSHIFT;
    369 	m->blkno = bp->b_blkno;
    370 
    371 	UVMHIST_LOG(ubchist, "old vp %p blkno 0x%x new blkno 0x%x",
    372 		    vp, bp->b_lblkno, bp->b_blkno, 0);
    373 
    374 	VOP_STRATEGY(bp);
    375 	error = biowait(bp);
    376 
    377 UVMHIST_LOG(ubchist, "error %d", error,0,0,0);
    378 
    379 	uvm_pagermapout(kva, *ap->a_count);
    380 
    381 	if (error) {
    382 		simple_lock(&uobj->vmobjlock);
    383 		if (m->flags & PG_WANTED)
    384 			thread_wakeup(m);	/* object lock still held */
    385 
    386 		m->flags &= ~(PG_WANTED|PG_BUSY);
    387 		UVM_PAGE_OWN(m, NULL);
    388 		uvm_lock_pageq();
    389 		uvm_pagefree(m);
    390 		uvm_unlock_pageq();
    391 		simple_unlock(&uobj->vmobjlock);
    392 	} else {
    393 		m->flags &= ~PG_FAKE;
    394 		pmap_clear_modify(PMAP_PGARG(m));
    395 	}
    396 
    397 	return error;
    398 }
    399 
    400 /*
    401  * Vnode op for VM putpages.
    402  */
    403 int
    404 ffs_putpages(v)
    405 	void *v;
    406 {
    407 	struct vop_putpages_args /* {
    408 		struct vnode *a_vp;
    409 		vm_page_t *a_m;
    410 		int a_count;
    411 		int a_sync;
    412 		int *a_rtvals;
    413 	} */ *ap = v;
    414 
    415 	int error;
    416 	struct uio uio;
    417 	struct iovec iov;
    418 	vm_page_t m;
    419 	vaddr_t kva;
    420 	struct buf tmpbuf, *bp;
    421 	struct vnode *vp = ap->a_vp;
    422 	struct inode *ip = VTOI(vp);
    423 	struct fs *fs = ip->i_fs;
    424 	struct ucred *cred = curproc->p_ucred;	/* XXX curproc */
    425 	UVMHIST_FUNC("ffs_putpages"); UVMHIST_CALLED(ubchist);
    426 
    427 	/* XXX for now, just do one page at a time */
    428 	if (ap->a_count != 1) {
    429 	    panic("ffs_putpages: one at a time, please\n");
    430 	}
    431 
    432 	m = ap->a_m[0];
    433 	kva = uvm_pagermapin(ap->a_m, ap->a_count, NULL, M_WAITOK);
    434 	if (kva == 0) {
    435 	    printf("uvm_pagermapin failed\n");
    436 	    return EAGAIN;
    437 	}
    438 
    439 	uio.uio_iov = &iov;
    440 	iov.iov_len = 0;
    441 
    442 	bp = &tmpbuf;
    443 	bzero(bp, sizeof *bp);
    444 
    445 	bp->b_bufsize = PAGE_SIZE;
    446 	bp->b_data = (void *)kva;
    447 	bp->b_lblkno = lblkno(fs, m->offset);
    448 	bp->b_bcount = min(PAGE_SIZE,
    449 			   fragroundup(fs, vp->v_uvm.u_size - m->offset));
    450 
    451 	bp->b_vp = vp;
    452 	bp->b_flags = B_BUSY|B_WRITE|B_WRITEINPROG;
    453 
    454 UVMHIST_LOG(ubchist, "bp %p vp %p blkno 0x%x",
    455        bp, vp, bp->b_lblkno, 0);
    456 
    457 	/*
    458 	 * if the blkno wasn't set in the page, do a bmap to find it.
    459 	 * currently this should only happen if the block is unallocated.
    460 	 * we'll always want to set the page's blkno if it's allocated
    461 	 * to help prevent memory deadlocks.  we probably even want to
    462 	 * allocate blocks in getpage for this same reason.
    463 	 *
    464 	 * once we switch to doing that, the page should always have a blkno.
    465 	 * but for now, we'll handle allocating blocks here too.
    466 	 */
    467 
    468 	bp->b_blkno = m->blkno;
    469 	if (bp->b_blkno == 0) {
    470 		error = VOP_BMAP(vp, bp->b_lblkno, NULL, &bp->b_blkno, NULL);
    471 		if (error) {
    472 UVMHIST_LOG(ubchist, "VOP_BMAP error %d", error,0,0,0);
    473 			return (error);
    474 		}
    475 UVMHIST_LOG(ubchist, "VOP_BMAP gave 0x%x", bp->b_blkno,0,0,0);
    476 	}
    477 
    478 	if ((long)bp->b_blkno == -1) {
    479 		int bsize;
    480 
    481 printf("ffs_putpages: bmap failed, vp %p bp %p lblkno %d\n",
    482        vp, bp, bp->b_lblkno);
    483 
    484 		bsize = blksize(fs, ip, lblkno(fs, m->offset));
    485 		error = ffs_balloc(ip, bp->b_lblkno, bsize, cred, NULL, 0);
    486 		if (error) {
    487 			printf("ffs_balloc -> %d\n", error);
    488 			return error;
    489 		}
    490 
    491 		/*
    492 		 * XXX we need to set the blkno in the page now,
    493 		 * how do we retrieve that?  maybe ffs_balloc sets these?
    494 		 */
    495 	}
    496 
    497 	if (m->blkno == 0) {
    498 		/* adjust physical blkno for partial blocks */
    499 		bp->b_blkno += ((m->offset - lblktosize(fs, bp->b_lblkno))
    500 				>> DEV_BSHIFT);
    501 		m->blkno = bp->b_blkno;
    502 	}
    503 
    504 	UVMHIST_LOG(ubchist, "old vp %p blkno 0x%x new blkno 0x%x",
    505 		    vp, bp->b_lblkno, bp->b_blkno, 0);
    506 
    507 	vp->v_numoutput++;
    508 
    509 	VOP_STRATEGY(bp);
    510 
    511 	/*
    512 	 * XXX
    513 	 * should only have to wait if (ap->a_sync),
    514 	 * but there's no async vnode io yet.
    515 	 */
    516 	error = biowait(bp);
    517 
    518 UVMHIST_LOG(ubchist, "error %d", error,0,0,0);
    519 
    520 	uvm_pagermapout(kva, ap->a_count);
    521 
    522 	return error;
    523 }
    524 #endif
    525