xref: /dragonfly/sys/vfs/hammer/hammer_vnops.c (revision cae2835b)
1 /*
2  * Copyright (c) 2007-2008 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@backplane.com>
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  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/mountctl.h>
36 #include <sys/namecache.h>
37 #include <sys/buf2.h>
38 #include <vfs/fifofs/fifo.h>
39 
40 #include "hammer.h"
41 
42 /*
43  * USERFS VNOPS
44  */
45 static int hammer_vop_fsync(struct vop_fsync_args *);
46 static int hammer_vop_read(struct vop_read_args *);
47 static int hammer_vop_write(struct vop_write_args *);
48 static int hammer_vop_access(struct vop_access_args *);
49 static int hammer_vop_advlock(struct vop_advlock_args *);
50 static int hammer_vop_close(struct vop_close_args *);
51 static int hammer_vop_ncreate(struct vop_ncreate_args *);
52 static int hammer_vop_getattr(struct vop_getattr_args *);
53 static int hammer_vop_nresolve(struct vop_nresolve_args *);
54 static int hammer_vop_nlookupdotdot(struct vop_nlookupdotdot_args *);
55 static int hammer_vop_nlink(struct vop_nlink_args *);
56 static int hammer_vop_nmkdir(struct vop_nmkdir_args *);
57 static int hammer_vop_nmknod(struct vop_nmknod_args *);
58 static int hammer_vop_open(struct vop_open_args *);
59 static int hammer_vop_print(struct vop_print_args *);
60 static int hammer_vop_readdir(struct vop_readdir_args *);
61 static int hammer_vop_readlink(struct vop_readlink_args *);
62 static int hammer_vop_nremove(struct vop_nremove_args *);
63 static int hammer_vop_nrename(struct vop_nrename_args *);
64 static int hammer_vop_nrmdir(struct vop_nrmdir_args *);
65 static int hammer_vop_markatime(struct vop_markatime_args *);
66 static int hammer_vop_setattr(struct vop_setattr_args *);
67 static int hammer_vop_strategy(struct vop_strategy_args *);
68 static int hammer_vop_bmap(struct vop_bmap_args *ap);
69 static int hammer_vop_nsymlink(struct vop_nsymlink_args *);
70 static int hammer_vop_nwhiteout(struct vop_nwhiteout_args *);
71 static int hammer_vop_ioctl(struct vop_ioctl_args *);
72 static int hammer_vop_mountctl(struct vop_mountctl_args *);
73 static int hammer_vop_kqfilter (struct vop_kqfilter_args *);
74 
75 static int hammer_vop_fifoclose (struct vop_close_args *);
76 static int hammer_vop_fiforead (struct vop_read_args *);
77 static int hammer_vop_fifowrite (struct vop_write_args *);
78 static int hammer_vop_fifokqfilter (struct vop_kqfilter_args *);
79 
80 struct vop_ops hammer_vnode_vops = {
81 	.vop_default =		vop_defaultop,
82 	.vop_fsync =		hammer_vop_fsync,
83 	.vop_getpages =		vop_stdgetpages,
84 	.vop_putpages =		vop_stdputpages,
85 	.vop_read =		hammer_vop_read,
86 	.vop_write =		hammer_vop_write,
87 	.vop_access =		hammer_vop_access,
88 	.vop_advlock =		hammer_vop_advlock,
89 	.vop_close =		hammer_vop_close,
90 	.vop_ncreate =		hammer_vop_ncreate,
91 	.vop_getattr =		hammer_vop_getattr,
92 	.vop_inactive =		hammer_vop_inactive,
93 	.vop_reclaim =		hammer_vop_reclaim,
94 	.vop_nresolve =		hammer_vop_nresolve,
95 	.vop_nlookupdotdot =	hammer_vop_nlookupdotdot,
96 	.vop_nlink =		hammer_vop_nlink,
97 	.vop_nmkdir =		hammer_vop_nmkdir,
98 	.vop_nmknod =		hammer_vop_nmknod,
99 	.vop_open =		hammer_vop_open,
100 	.vop_pathconf =		vop_stdpathconf,
101 	.vop_print =		hammer_vop_print,
102 	.vop_readdir =		hammer_vop_readdir,
103 	.vop_readlink =		hammer_vop_readlink,
104 	.vop_nremove =		hammer_vop_nremove,
105 	.vop_nrename =		hammer_vop_nrename,
106 	.vop_nrmdir =		hammer_vop_nrmdir,
107 	.vop_markatime =	hammer_vop_markatime,
108 	.vop_setattr =		hammer_vop_setattr,
109 	.vop_bmap =		hammer_vop_bmap,
110 	.vop_strategy =		hammer_vop_strategy,
111 	.vop_nsymlink =		hammer_vop_nsymlink,
112 	.vop_nwhiteout =	hammer_vop_nwhiteout,
113 	.vop_ioctl =		hammer_vop_ioctl,
114 	.vop_mountctl =		hammer_vop_mountctl,
115 	.vop_kqfilter =		hammer_vop_kqfilter
116 };
117 
118 struct vop_ops hammer_spec_vops = {
119 	.vop_default =		vop_defaultop,
120 	.vop_fsync =		hammer_vop_fsync,
121 	.vop_read =		vop_stdnoread,
122 	.vop_write =		vop_stdnowrite,
123 	.vop_access =		hammer_vop_access,
124 	.vop_close =		hammer_vop_close,
125 	.vop_markatime =	hammer_vop_markatime,
126 	.vop_getattr =		hammer_vop_getattr,
127 	.vop_inactive =		hammer_vop_inactive,
128 	.vop_reclaim =		hammer_vop_reclaim,
129 	.vop_setattr =		hammer_vop_setattr
130 };
131 
132 struct vop_ops hammer_fifo_vops = {
133 	.vop_default =		fifo_vnoperate,
134 	.vop_fsync =		hammer_vop_fsync,
135 	.vop_read =		hammer_vop_fiforead,
136 	.vop_write =		hammer_vop_fifowrite,
137 	.vop_access =		hammer_vop_access,
138 	.vop_close =		hammer_vop_fifoclose,
139 	.vop_markatime =	hammer_vop_markatime,
140 	.vop_getattr =		hammer_vop_getattr,
141 	.vop_inactive =		hammer_vop_inactive,
142 	.vop_reclaim =		hammer_vop_reclaim,
143 	.vop_setattr =		hammer_vop_setattr,
144 	.vop_kqfilter =		hammer_vop_fifokqfilter
145 };
146 
147 static __inline
148 void
149 hammer_knote(struct vnode *vp, int flags)
150 {
151 	if (flags)
152 		KNOTE(&vp->v_pollinfo.vpi_kqinfo.ki_note, flags);
153 }
154 
155 static int hammer_dounlink(hammer_transaction_t trans, struct nchandle *nch,
156 			   struct vnode *dvp, struct ucred *cred,
157 			   int flags, int isdir);
158 static int hammer_vop_strategy_read(struct vop_strategy_args *ap);
159 static int hammer_vop_strategy_write(struct vop_strategy_args *ap);
160 
161 /*
162  * hammer_vop_fsync { vp, waitfor }
163  *
164  * fsync() an inode to disk and wait for it to be completely committed
165  * such that the information would not be undone if a crash occured after
166  * return.
167  *
168  * NOTE: HAMMER's fsync()'s are going to remain expensive until we implement
169  *	 a REDO log.  A sysctl is provided to relax HAMMER's fsync()
170  *	 operation.
171  *
172  *	 Ultimately the combination of a REDO log and use of fast storage
173  *	 to front-end cluster caches will make fsync fast, but it aint
174  *	 here yet.  And, in anycase, we need real transactional
175  *	 all-or-nothing features which are not restricted to a single file.
176  */
177 static
178 int
179 hammer_vop_fsync(struct vop_fsync_args *ap)
180 {
181 	hammer_inode_t ip = VTOI(ap->a_vp);
182 	hammer_mount_t hmp = ip->hmp;
183 	int waitfor = ap->a_waitfor;
184 	int mode;
185 
186 	lwkt_gettoken(&hmp->fs_token);
187 
188 	/*
189 	 * Fsync rule relaxation (default is either full synchronous flush
190 	 * or REDO semantics with synchronous flush).
191 	 */
192 	if (ap->a_flags & VOP_FSYNC_SYSCALL) {
193 		switch(hammer_fsync_mode) {
194 		case 0:
195 mode0:
196 			/* no REDO, full synchronous flush */
197 			goto skip;
198 		case 1:
199 mode1:
200 			/* no REDO, full asynchronous flush */
201 			if (waitfor == MNT_WAIT)
202 				waitfor = MNT_NOWAIT;
203 			goto skip;
204 		case 2:
205 			/* REDO semantics, synchronous flush */
206 			if (hmp->version < HAMMER_VOL_VERSION_FOUR)
207 				goto mode0;
208 			mode = HAMMER_FLUSH_UNDOS_AUTO;
209 			break;
210 		case 3:
211 			/* REDO semantics, relaxed asynchronous flush */
212 			if (hmp->version < HAMMER_VOL_VERSION_FOUR)
213 				goto mode1;
214 			mode = HAMMER_FLUSH_UNDOS_RELAXED;
215 			if (waitfor == MNT_WAIT)
216 				waitfor = MNT_NOWAIT;
217 			break;
218 		case 4:
219 			/* ignore the fsync() system call */
220 			lwkt_reltoken(&hmp->fs_token);
221 			return(0);
222 		default:
223 			/* we have to do something */
224 			mode = HAMMER_FLUSH_UNDOS_RELAXED;
225 			if (waitfor == MNT_WAIT)
226 				waitfor = MNT_NOWAIT;
227 			break;
228 		}
229 
230 		/*
231 		 * Fast fsync only needs to flush the UNDO/REDO fifo if
232 		 * HAMMER_INODE_REDO is non-zero and the only modifications
233 		 * made to the file are write or write-extends.
234 		 */
235 		if ((ip->flags & HAMMER_INODE_REDO) &&
236 		    (ip->flags & HAMMER_INODE_MODMASK_NOREDO) == 0) {
237 			++hammer_count_fsyncs;
238 			hammer_flusher_flush_undos(hmp, mode);
239 			ip->redo_count = 0;
240 			if (ip->vp && (ip->flags & HAMMER_INODE_MODMASK) == 0)
241 				vclrisdirty(ip->vp);
242 			lwkt_reltoken(&hmp->fs_token);
243 			return(0);
244 		}
245 
246 		/*
247 		 * REDO is enabled by fsync(), the idea being we really only
248 		 * want to lay down REDO records when programs are using
249 		 * fsync() heavily.  The first fsync() on the file starts
250 		 * the gravy train going and later fsync()s keep it hot by
251 		 * resetting the redo_count.
252 		 *
253 		 * We weren't running REDOs before now so we have to fall
254 		 * through and do a full fsync of what we have.
255 		 */
256 		if (hmp->version >= HAMMER_VOL_VERSION_FOUR &&
257 		    (hmp->flags & HAMMER_MOUNT_REDO_RECOVERY_RUN) == 0) {
258 			ip->flags |= HAMMER_INODE_REDO;
259 			ip->redo_count = 0;
260 		}
261 	}
262 skip:
263 
264 	/*
265 	 * Do a full flush sequence.
266 	 *
267 	 * Attempt to release the vnode while waiting for the inode to
268 	 * finish flushing.  This can really mess up inactive->reclaim
269 	 * sequences so only do it if the vnode is active.
270 	 *
271 	 * WARNING! The VX lock functions must be used.  vn_lock() will
272 	 *	    fail when this is part of a VOP_RECLAIM sequence.
273 	 */
274 	++hammer_count_fsyncs;
275 	vfsync(ap->a_vp, waitfor, 1, NULL, NULL);
276 	hammer_flush_inode(ip, HAMMER_FLUSH_SIGNAL);
277 	if (waitfor == MNT_WAIT) {
278 		int dorelock;
279 
280 		if ((ap->a_vp->v_flag & VRECLAIMED) == 0) {
281 			vx_unlock(ap->a_vp);
282 			dorelock = 1;
283 		} else {
284 			dorelock = 0;
285 		}
286 		hammer_wait_inode(ip);
287 		if (dorelock)
288 			vx_lock(ap->a_vp);
289 	}
290 	if (ip->vp && (ip->flags & HAMMER_INODE_MODMASK) == 0)
291 		vclrisdirty(ip->vp);
292 	lwkt_reltoken(&hmp->fs_token);
293 	return (ip->error);
294 }
295 
296 /*
297  * hammer_vop_read { vp, uio, ioflag, cred }
298  *
299  * MPSAFE (for the cache safe does not require fs_token)
300  */
301 static
302 int
303 hammer_vop_read(struct vop_read_args *ap)
304 {
305 	struct hammer_transaction trans;
306 	hammer_inode_t ip;
307 	hammer_mount_t hmp;
308 	off_t offset;
309 	struct buf *bp;
310 	struct uio *uio;
311 	int error;
312 	int n;
313 	int seqcount;
314 	int ioseqcount;
315 	int blksize;
316 	int bigread;
317 	int got_trans;
318 	size_t resid;
319 
320 	if (ap->a_vp->v_type != VREG)
321 		return (EINVAL);
322 	ip = VTOI(ap->a_vp);
323 	hmp = ip->hmp;
324 	error = 0;
325 	got_trans = 0;
326 	uio = ap->a_uio;
327 
328 	/*
329 	 * Attempt to shortcut directly to the VM object using lwbufs.
330 	 * This is much faster than instantiating buffer cache buffers.
331 	 */
332 	resid = uio->uio_resid;
333 	error = vop_helper_read_shortcut(ap);
334 	hammer_stats_file_read += resid - uio->uio_resid;
335 	if (error)
336 		return (error);
337 	if (uio->uio_resid == 0)
338 		goto finished;
339 
340 	/*
341 	 * Allow the UIO's size to override the sequential heuristic.
342 	 */
343 	blksize = hammer_blocksize(uio->uio_offset);
344 	seqcount = (uio->uio_resid + (MAXBSIZE - 1)) / MAXBSIZE;
345 	ioseqcount = (ap->a_ioflag >> 16);
346 	if (seqcount < ioseqcount)
347 		seqcount = ioseqcount;
348 
349 	/*
350 	 * If reading or writing a huge amount of data we have to break
351 	 * atomicy and allow the operation to be interrupted by a signal
352 	 * or it can DOS the machine.
353 	 */
354 	bigread = (uio->uio_resid > 100 * 1024 * 1024);
355 
356 	/*
357 	 * Access the data typically in HAMMER_BUFSIZE blocks via the
358 	 * buffer cache, but HAMMER may use a variable block size based
359 	 * on the offset.
360 	 *
361 	 * XXX Temporary hack, delay the start transaction while we remain
362 	 *     MPSAFE.  NOTE: ino_data.size cannot change while vnode is
363 	 *     locked-shared.
364 	 */
365 	while (uio->uio_resid > 0 && uio->uio_offset < ip->ino_data.size) {
366 		int64_t base_offset;
367 		int64_t file_limit;
368 
369 		blksize = hammer_blocksize(uio->uio_offset);
370 		offset = (int)uio->uio_offset & (blksize - 1);
371 		base_offset = uio->uio_offset - offset;
372 
373 		if (bigread && (error = hammer_signal_check(ip->hmp)) != 0)
374 			break;
375 
376 		/*
377 		 * MPSAFE
378 		 */
379 		bp = getblk(ap->a_vp, base_offset, blksize, 0, 0);
380 		if ((bp->b_flags & (B_INVAL | B_CACHE | B_RAM)) == B_CACHE) {
381 			bp->b_flags &= ~B_AGE;
382 			error = 0;
383 			goto skip;
384 		}
385 		if (ap->a_ioflag & IO_NRDELAY) {
386 			bqrelse(bp);
387 			return (EWOULDBLOCK);
388 		}
389 
390 		/*
391 		 * MPUNSAFE
392 		 */
393 		if (got_trans == 0) {
394 			hammer_start_transaction(&trans, ip->hmp);
395 			got_trans = 1;
396 		}
397 
398 		/*
399 		 * NOTE: A valid bp has already been acquired, but was not
400 		 *	 B_CACHE.
401 		 */
402 		if (hammer_cluster_enable) {
403 			/*
404 			 * Use file_limit to prevent cluster_read() from
405 			 * creating buffers of the wrong block size past
406 			 * the demarc.
407 			 */
408 			file_limit = ip->ino_data.size;
409 			if (base_offset < HAMMER_XDEMARC &&
410 			    file_limit > HAMMER_XDEMARC) {
411 				file_limit = HAMMER_XDEMARC;
412 			}
413 			error = cluster_readx(ap->a_vp,
414 					     file_limit, base_offset,
415 					     blksize, uio->uio_resid,
416 					     seqcount * MAXBSIZE, &bp);
417 		} else {
418 			error = breadnx(ap->a_vp, base_offset, blksize,
419 					NULL, NULL, 0, &bp);
420 		}
421 		if (error) {
422 			brelse(bp);
423 			break;
424 		}
425 skip:
426 		if ((hammer_debug_io & 0x0001) && (bp->b_flags & B_IOISSUED)) {
427 			hdkprintf("zone2_offset %016jx read file %016jx@%016jx\n",
428 				(intmax_t)bp->b_bio2.bio_offset,
429 				(intmax_t)ip->obj_id,
430 				(intmax_t)bp->b_loffset);
431 		}
432 		bp->b_flags &= ~B_IOISSUED;
433 		if (blksize == HAMMER_XBUFSIZE)
434 			bp->b_flags |= B_CLUSTEROK;
435 
436 		n = blksize - offset;
437 		if (n > uio->uio_resid)
438 			n = uio->uio_resid;
439 		if (n > ip->ino_data.size - uio->uio_offset)
440 			n = (int)(ip->ino_data.size - uio->uio_offset);
441 
442 		/*
443 		 * Set B_AGE, data has a lower priority than meta-data.
444 		 *
445 		 * Use a hold/unlock/drop sequence to run the uiomove
446 		 * with the buffer unlocked, avoiding deadlocks against
447 		 * read()s on mmap()'d spaces.
448 		 */
449 		bp->b_flags |= B_AGE;
450 		error = uiomovebp(bp, (char *)bp->b_data + offset, n, uio);
451 		bqrelse(bp);
452 
453 		if (error)
454 			break;
455 		hammer_stats_file_read += n;
456 	}
457 
458 finished:
459 
460 	/*
461 	 * Try to update the atime with just the inode lock for maximum
462 	 * concurrency.  If we can't shortcut it we have to get the full
463 	 * blown transaction.
464 	 */
465 	if (got_trans == 0 && hammer_update_atime_quick(ip) < 0) {
466 		hammer_start_transaction(&trans, ip->hmp);
467 		got_trans = 1;
468 	}
469 
470 	if (got_trans) {
471 		if ((ip->flags & HAMMER_INODE_RO) == 0 &&
472 		    (ip->hmp->mp->mnt_flag & MNT_NOATIME) == 0) {
473 			lwkt_gettoken(&hmp->fs_token);
474 			ip->ino_data.atime = trans.time;
475 			hammer_modify_inode(&trans, ip, HAMMER_INODE_ATIME);
476 			hammer_done_transaction(&trans);
477 			lwkt_reltoken(&hmp->fs_token);
478 		} else {
479 			hammer_done_transaction(&trans);
480 		}
481 	}
482 	return (error);
483 }
484 
485 /*
486  * hammer_vop_write { vp, uio, ioflag, cred }
487  */
488 static
489 int
490 hammer_vop_write(struct vop_write_args *ap)
491 {
492 	struct hammer_transaction trans;
493 	hammer_inode_t ip;
494 	hammer_mount_t hmp;
495 	thread_t td;
496 	struct uio *uio;
497 	int offset;
498 	off_t base_offset;
499 	int64_t cluster_eof;
500 	struct buf *bp;
501 	int kflags;
502 	int error;
503 	int n;
504 	int flags;
505 	int seqcount;
506 	int bigwrite;
507 
508 	if (ap->a_vp->v_type != VREG)
509 		return (EINVAL);
510 	ip = VTOI(ap->a_vp);
511 	hmp = ip->hmp;
512 	error = 0;
513 	kflags = 0;
514 	seqcount = ap->a_ioflag >> 16;
515 
516 	if (ip->flags & HAMMER_INODE_RO)
517 		return (EROFS);
518 
519 	/*
520 	 * Create a transaction to cover the operations we perform.
521 	 */
522 	hammer_start_transaction(&trans, hmp);
523 	uio = ap->a_uio;
524 
525 	/*
526 	 * Check append mode
527 	 */
528 	if (ap->a_ioflag & IO_APPEND)
529 		uio->uio_offset = ip->ino_data.size;
530 
531 	/*
532 	 * Check for illegal write offsets.  Valid range is 0...2^63-1.
533 	 *
534 	 * NOTE: the base_off assignment is required to work around what
535 	 * I consider to be a GCC-4 optimization bug.
536 	 */
537 	if (uio->uio_offset < 0) {
538 		hammer_done_transaction(&trans);
539 		return (EFBIG);
540 	}
541 	base_offset = uio->uio_offset + uio->uio_resid;	/* work around gcc-4 */
542 	if (uio->uio_resid > 0 && base_offset <= uio->uio_offset) {
543 		hammer_done_transaction(&trans);
544 		return (EFBIG);
545 	}
546 
547 	if (uio->uio_resid > 0 && (td = uio->uio_td) != NULL && td->td_proc &&
548 	    base_offset > td->td_proc->p_rlimit[RLIMIT_FSIZE].rlim_cur) {
549 		hammer_done_transaction(&trans);
550 		lwpsignal(td->td_proc, td->td_lwp, SIGXFSZ);
551 		return (EFBIG);
552 	}
553 
554 	/*
555 	 * If reading or writing a huge amount of data we have to break
556 	 * atomicy and allow the operation to be interrupted by a signal
557 	 * or it can DOS the machine.
558 	 *
559 	 * Preset redo_count so we stop generating REDOs earlier if the
560 	 * limit is exceeded.
561 	 *
562 	 * redo_count is heuristical, SMP races are ok
563 	 */
564 	bigwrite = (uio->uio_resid > 100 * 1024 * 1024);
565 	if ((ip->flags & HAMMER_INODE_REDO) &&
566 	    ip->redo_count < hammer_limit_redo) {
567 		ip->redo_count += uio->uio_resid;
568 	}
569 
570 	/*
571 	 * Access the data typically in HAMMER_BUFSIZE blocks via the
572 	 * buffer cache, but HAMMER may use a variable block size based
573 	 * on the offset.
574 	 */
575 	while (uio->uio_resid > 0) {
576 		int fixsize = 0;
577 		int blksize;
578 		int blkmask;
579 		int trivial;
580 		int endofblk;
581 		off_t nsize;
582 
583 		if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_WRITE)) != 0)
584 			break;
585 		if (bigwrite && (error = hammer_signal_check(hmp)) != 0)
586 			break;
587 
588 		blksize = hammer_blocksize(uio->uio_offset);
589 
590 		/*
591 		 * Control the number of pending records associated with
592 		 * this inode.  If too many have accumulated start a
593 		 * flush.  Try to maintain a pipeline with the flusher.
594 		 *
595 		 * NOTE: It is possible for other sources to grow the
596 		 *	 records but not necessarily issue another flush,
597 		 *	 so use a timeout and ensure that a re-flush occurs.
598 		 */
599 		if (ip->rsv_recs >= hammer_limit_inode_recs) {
600 			lwkt_gettoken(&hmp->fs_token);
601 			hammer_flush_inode(ip, HAMMER_FLUSH_SIGNAL);
602 			while (ip->rsv_recs >= hammer_limit_inode_recs * 2) {
603 				ip->flags |= HAMMER_INODE_RECSW;
604 				tsleep(&ip->rsv_recs, 0, "hmrwww", hz);
605 				hammer_flush_inode(ip, HAMMER_FLUSH_SIGNAL);
606 			}
607 			lwkt_reltoken(&hmp->fs_token);
608 		}
609 
610 		/*
611 		 * Do not allow HAMMER to blow out the buffer cache.  Very
612 		 * large UIOs can lockout other processes due to bwillwrite()
613 		 * mechanics.
614 		 *
615 		 * The hammer inode is not locked during these operations.
616 		 * The vnode is locked which can interfere with the pageout
617 		 * daemon for non-UIO_NOCOPY writes but should not interfere
618 		 * with the buffer cache.  Even so, we cannot afford to
619 		 * allow the pageout daemon to build up too many dirty buffer
620 		 * cache buffers.
621 		 *
622 		 * Only call this if we aren't being recursively called from
623 		 * a virtual disk device (vn), else we may deadlock.
624 		 */
625 		if ((ap->a_ioflag & IO_RECURSE) == 0)
626 			bwillwrite(blksize);
627 
628 		/*
629 		 * Calculate the blocksize at the current offset and figure
630 		 * out how much we can actually write.
631 		 */
632 		blkmask = blksize - 1;
633 		offset = (int)uio->uio_offset & blkmask;
634 		base_offset = uio->uio_offset & ~(int64_t)blkmask;
635 		n = blksize - offset;
636 		if (n > uio->uio_resid) {
637 			n = uio->uio_resid;
638 			endofblk = 0;
639 		} else {
640 			endofblk = 1;
641 		}
642 		nsize = uio->uio_offset + n;
643 		if (nsize > ip->ino_data.size) {
644 			if (uio->uio_offset > ip->ino_data.size)
645 				trivial = 0;
646 			else
647 				trivial = 1;
648 			nvextendbuf(ap->a_vp,
649 				    ip->ino_data.size,
650 				    nsize,
651 				    hammer_blocksize(ip->ino_data.size),
652 				    hammer_blocksize(nsize),
653 				    hammer_blockoff(ip->ino_data.size),
654 				    hammer_blockoff(nsize),
655 				    trivial);
656 			fixsize = 1;
657 			kflags |= NOTE_EXTEND;
658 		}
659 
660 		if (uio->uio_segflg == UIO_NOCOPY) {
661 			/*
662 			 * Issuing a write with the same data backing the
663 			 * buffer.  Instantiate the buffer to collect the
664 			 * backing vm pages, then read-in any missing bits.
665 			 *
666 			 * This case is used by vop_stdputpages().
667 			 */
668 			bp = getblk(ap->a_vp, base_offset,
669 				    blksize, GETBLK_BHEAVY, 0);
670 			if ((bp->b_flags & B_CACHE) == 0) {
671 				bqrelse(bp);
672 				error = bread(ap->a_vp, base_offset,
673 					      blksize, &bp);
674 			}
675 		} else if (offset == 0 && uio->uio_resid >= blksize) {
676 			/*
677 			 * Even though we are entirely overwriting the buffer
678 			 * we may still have to zero it out to avoid a
679 			 * mmap/write visibility issue.
680 			 */
681 			bp = getblk(ap->a_vp, base_offset, blksize, GETBLK_BHEAVY, 0);
682 			if ((bp->b_flags & B_CACHE) == 0)
683 				vfs_bio_clrbuf(bp);
684 		} else if (base_offset >= ip->ino_data.size) {
685 			/*
686 			 * If the base offset of the buffer is beyond the
687 			 * file EOF, we don't have to issue a read.
688 			 */
689 			bp = getblk(ap->a_vp, base_offset,
690 				    blksize, GETBLK_BHEAVY, 0);
691 			vfs_bio_clrbuf(bp);
692 		} else {
693 			/*
694 			 * Partial overwrite, read in any missing bits then
695 			 * replace the portion being written.
696 			 */
697 			error = bread(ap->a_vp, base_offset, blksize, &bp);
698 			if (error == 0)
699 				bheavy(bp);
700 		}
701 		if (error == 0)
702 			error = uiomovebp(bp, bp->b_data + offset, n, uio);
703 
704 		lwkt_gettoken(&hmp->fs_token);
705 
706 		/*
707 		 * Generate REDO records if enabled and redo_count will not
708 		 * exceeded the limit.
709 		 *
710 		 * If redo_count exceeds the limit we stop generating records
711 		 * and clear HAMMER_INODE_REDO.  This will cause the next
712 		 * fsync() to do a full meta-data sync instead of just an
713 		 * UNDO/REDO fifo update.
714 		 *
715 		 * When clearing HAMMER_INODE_REDO any pre-existing REDOs
716 		 * will still be tracked.  The tracks will be terminated
717 		 * when the related meta-data (including possible data
718 		 * modifications which are not tracked via REDO) is
719 		 * flushed.
720 		 */
721 		if ((ip->flags & HAMMER_INODE_REDO) && error == 0) {
722 			if (ip->redo_count < hammer_limit_redo) {
723 				bp->b_flags |= B_VFSFLAG1;
724 				error = hammer_generate_redo(&trans, ip,
725 						     base_offset + offset,
726 						     HAMMER_REDO_WRITE,
727 						     bp->b_data + offset,
728 						     (size_t)n);
729 			} else {
730 				ip->flags &= ~HAMMER_INODE_REDO;
731 			}
732 		}
733 
734 		/*
735 		 * If we screwed up we have to undo any VM size changes we
736 		 * made.
737 		 */
738 		if (error) {
739 			brelse(bp);
740 			if (fixsize) {
741 				nvtruncbuf(ap->a_vp, ip->ino_data.size,
742 					  hammer_blocksize(ip->ino_data.size),
743 					  hammer_blockoff(ip->ino_data.size),
744 					  0);
745 			}
746 			lwkt_reltoken(&hmp->fs_token);
747 			break;
748 		}
749 		kflags |= NOTE_WRITE;
750 		hammer_stats_file_write += n;
751 		if (blksize == HAMMER_XBUFSIZE)
752 			bp->b_flags |= B_CLUSTEROK;
753 		if (ip->ino_data.size < uio->uio_offset) {
754 			ip->ino_data.size = uio->uio_offset;
755 			flags = HAMMER_INODE_SDIRTY;
756 		} else {
757 			flags = 0;
758 		}
759 		ip->ino_data.mtime = trans.time;
760 		flags |= HAMMER_INODE_MTIME | HAMMER_INODE_BUFS;
761 		hammer_modify_inode(&trans, ip, flags);
762 
763 		/*
764 		 * Once we dirty the buffer any cached zone-X offset
765 		 * becomes invalid.  HAMMER NOTE: no-history mode cannot
766 		 * allow overwriting over the same data sector unless
767 		 * we provide UNDOs for the old data, which we don't.
768 		 */
769 		bp->b_bio2.bio_offset = NOOFFSET;
770 
771 		lwkt_reltoken(&hmp->fs_token);
772 
773 		/*
774 		 * Final buffer disposition.
775 		 *
776 		 * Because meta-data updates are deferred, HAMMER is
777 		 * especially sensitive to excessive bdwrite()s because
778 		 * the I/O stream is not broken up by disk reads.  So the
779 		 * buffer cache simply cannot keep up.
780 		 *
781 		 * WARNING!  blksize is variable.  cluster_write() is
782 		 *	     expected to not blow up if it encounters
783 		 *	     buffers that do not match the passed blksize.
784 		 *
785 		 * NOTE!  Hammer shouldn't need to bawrite()/cluster_write().
786 		 *	  The ip->rsv_recs check should burst-flush the data.
787 		 *	  If we queue it immediately the buf could be left
788 		 *	  locked on the device queue for a very long time.
789 		 *
790 		 *	  However, failing to flush a dirty buffer out when
791 		 *        issued from the pageout daemon can result in a low
792 		 *        memory deadlock against bio_page_alloc(), so we
793 		 *	  have to bawrite() on IO_ASYNC as well.
794 		 *
795 		 * NOTE!  To avoid degenerate stalls due to mismatched block
796 		 *	  sizes we only honor IO_DIRECT on the write which
797 		 *	  abuts the end of the buffer.  However, we must
798 		 *	  honor IO_SYNC in case someone is silly enough to
799 		 *	  configure a HAMMER file as swap, or when HAMMER
800 		 *	  is serving NFS (for commits).  Ick ick.
801 		 */
802 		bp->b_flags |= B_AGE;
803 		if (blksize == HAMMER_XBUFSIZE)
804 			bp->b_flags |= B_CLUSTEROK;
805 
806 		if (ap->a_ioflag & IO_SYNC) {
807 			bwrite(bp);
808 		} else if ((ap->a_ioflag & IO_DIRECT) && endofblk) {
809 			bawrite(bp);
810 		} else if (ap->a_ioflag & IO_ASYNC) {
811 			bawrite(bp);
812 		} else if (hammer_cluster_enable &&
813 			   !(ap->a_vp->v_mount->mnt_flag & MNT_NOCLUSTERW)) {
814 			if (base_offset < HAMMER_XDEMARC)
815 				cluster_eof = hammer_blockdemarc(base_offset,
816 							 ip->ino_data.size);
817 			else
818 				cluster_eof = ip->ino_data.size;
819 			cluster_write(bp, cluster_eof, blksize, seqcount);
820 		} else {
821 			bdwrite(bp);
822 		}
823 	}
824 	hammer_done_transaction(&trans);
825 	hammer_knote(ap->a_vp, kflags);
826 
827 	return (error);
828 }
829 
830 /*
831  * hammer_vop_access { vp, mode, cred }
832  *
833  * MPSAFE - does not require fs_token
834  */
835 static
836 int
837 hammer_vop_access(struct vop_access_args *ap)
838 {
839 	hammer_inode_t ip = VTOI(ap->a_vp);
840 	uid_t uid;
841 	gid_t gid;
842 	int error;
843 
844 	++hammer_stats_file_iopsr;
845 	uid = hammer_to_unix_xid(&ip->ino_data.uid);
846 	gid = hammer_to_unix_xid(&ip->ino_data.gid);
847 
848 	error = vop_helper_access(ap, uid, gid, ip->ino_data.mode,
849 				  ip->ino_data.uflags);
850 	return (error);
851 }
852 
853 /*
854  * hammer_vop_advlock { vp, id, op, fl, flags }
855  *
856  * MPSAFE - does not require fs_token
857  */
858 static
859 int
860 hammer_vop_advlock(struct vop_advlock_args *ap)
861 {
862 	hammer_inode_t ip = VTOI(ap->a_vp);
863 
864 	return (lf_advlock(ap, &ip->advlock, ip->ino_data.size));
865 }
866 
867 /*
868  * hammer_vop_close { vp, fflag }
869  *
870  * We can only sync-on-close for normal closes.  XXX disabled for now.
871  */
872 static
873 int
874 hammer_vop_close(struct vop_close_args *ap)
875 {
876 #if 0
877 	struct vnode *vp = ap->a_vp;
878 	hammer_inode_t ip = VTOI(vp);
879 	int waitfor;
880 	if (ip->flags & (HAMMER_INODE_CLOSESYNC|HAMMER_INODE_CLOSEASYNC)) {
881 		if (vn_islocked(vp) == LK_EXCLUSIVE &&
882 		    (vp->v_flag & (VINACTIVE|VRECLAIMED)) == 0) {
883 			if (ip->flags & HAMMER_INODE_CLOSESYNC)
884 				waitfor = MNT_WAIT;
885 			else
886 				waitfor = MNT_NOWAIT;
887 			ip->flags &= ~(HAMMER_INODE_CLOSESYNC |
888 				       HAMMER_INODE_CLOSEASYNC);
889 			VOP_FSYNC(vp, MNT_NOWAIT, waitfor);
890 		}
891 	}
892 #endif
893 	return (vop_stdclose(ap));
894 }
895 
896 /*
897  * hammer_vop_ncreate { nch, dvp, vpp, cred, vap }
898  *
899  * The operating system has already ensured that the directory entry
900  * does not exist and done all appropriate namespace locking.
901  */
902 static
903 int
904 hammer_vop_ncreate(struct vop_ncreate_args *ap)
905 {
906 	struct hammer_transaction trans;
907 	hammer_inode_t dip;
908 	hammer_inode_t nip;
909 	struct nchandle *nch;
910 	hammer_mount_t hmp;
911 	int error;
912 
913 	nch = ap->a_nch;
914 	dip = VTOI(ap->a_dvp);
915 	hmp = dip->hmp;
916 
917 	if (dip->flags & HAMMER_INODE_RO)
918 		return (EROFS);
919 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
920 		return (error);
921 
922 	/*
923 	 * Create a transaction to cover the operations we perform.
924 	 */
925 	lwkt_gettoken(&hmp->fs_token);
926 	hammer_start_transaction(&trans, hmp);
927 	++hammer_stats_file_iopsw;
928 
929 	/*
930 	 * Create a new filesystem object of the requested type.  The
931 	 * returned inode will be referenced and shared-locked to prevent
932 	 * it from being moved to the flusher.
933 	 */
934 	error = hammer_create_inode(&trans, ap->a_vap, ap->a_cred,
935 				    dip, nch->ncp->nc_name, nch->ncp->nc_nlen,
936 				    NULL, &nip);
937 	if (error) {
938 		hkprintf("hammer_create_inode error %d\n", error);
939 		hammer_done_transaction(&trans);
940 		*ap->a_vpp = NULL;
941 		lwkt_reltoken(&hmp->fs_token);
942 		return (error);
943 	}
944 
945 	/*
946 	 * Add the new filesystem object to the directory.  This will also
947 	 * bump the inode's link count.
948 	 */
949 	error = hammer_ip_add_direntry(&trans, dip,
950 					nch->ncp->nc_name, nch->ncp->nc_nlen,
951 					nip);
952 	if (error)
953 		hkprintf("hammer_ip_add_direntry error %d\n", error);
954 
955 	/*
956 	 * Finish up.
957 	 */
958 	if (error) {
959 		hammer_rel_inode(nip, 0);
960 		hammer_done_transaction(&trans);
961 		*ap->a_vpp = NULL;
962 	} else {
963 		error = hammer_get_vnode(nip, ap->a_vpp);
964 		hammer_done_transaction(&trans);
965 		hammer_rel_inode(nip, 0);
966 		if (error == 0) {
967 			cache_setunresolved(ap->a_nch);
968 			cache_setvp(ap->a_nch, *ap->a_vpp);
969 		}
970 		hammer_knote(ap->a_dvp, NOTE_WRITE);
971 	}
972 	lwkt_reltoken(&hmp->fs_token);
973 	return (error);
974 }
975 
976 /*
977  * hammer_vop_getattr { vp, vap }
978  *
979  * Retrieve an inode's attribute information.  When accessing inodes
980  * historically we fake the atime field to ensure consistent results.
981  * The atime field is stored in the B-Tree element and allowed to be
982  * updated without cycling the element.
983  *
984  * MPSAFE - does not require fs_token
985  */
986 static
987 int
988 hammer_vop_getattr(struct vop_getattr_args *ap)
989 {
990 	hammer_inode_t ip = VTOI(ap->a_vp);
991 	struct vattr *vap = ap->a_vap;
992 
993 	/*
994 	 * We want the fsid to be different when accessing a filesystem
995 	 * with different as-of's so programs like diff don't think
996 	 * the files are the same.
997 	 *
998 	 * We also want the fsid to be the same when comparing snapshots,
999 	 * or when comparing mirrors (which might be backed by different
1000 	 * physical devices).  HAMMER fsids are based on the PFS's
1001 	 * shared_uuid field.
1002 	 *
1003 	 * XXX there is a chance of collision here.  The va_fsid reported
1004 	 * by stat is different from the more involved fsid used in the
1005 	 * mount structure.
1006 	 */
1007 	++hammer_stats_file_iopsr;
1008 	hammer_lock_sh(&ip->lock);
1009 	vap->va_fsid = ip->pfsm->fsid_udev ^ (uint32_t)ip->obj_asof ^
1010 		       (uint32_t)(ip->obj_asof >> 32);
1011 
1012 	vap->va_fileid = ip->ino_leaf.base.obj_id;
1013 	vap->va_mode = ip->ino_data.mode;
1014 	vap->va_nlink = ip->ino_data.nlinks;
1015 	vap->va_uid = hammer_to_unix_xid(&ip->ino_data.uid);
1016 	vap->va_gid = hammer_to_unix_xid(&ip->ino_data.gid);
1017 	vap->va_rmajor = 0;
1018 	vap->va_rminor = 0;
1019 	vap->va_size = ip->ino_data.size;
1020 
1021 	/*
1022 	 * Special case for @@PFS softlinks.  The actual size of the
1023 	 * expanded softlink is "@@0x%016llx:%05d" == 26 bytes.
1024 	 * or for MAX_TID is    "@@-1:%05d" == 10 bytes.
1025 	 *
1026 	 * Note that userspace hammer command does not allow users to
1027 	 * create a @@PFS softlink under an existing other PFS (id!=0)
1028 	 * so the ip localization here for @@PFS softlink is always 0.
1029 	 */
1030 	if (ip->ino_data.obj_type == HAMMER_OBJTYPE_SOFTLINK &&
1031 	    ip->ino_data.size == 10 &&
1032 	    ip->obj_asof == HAMMER_MAX_TID &&
1033 	    ip->obj_localization == HAMMER_DEF_LOCALIZATION &&
1034 	    strncmp(ip->ino_data.ext.symlink, "@@PFS", 5) == 0) {
1035 		if (hammer_is_pfs_slave(&ip->pfsm->pfsd))
1036 			vap->va_size = 26;
1037 		else
1038 			vap->va_size = 10;
1039 	}
1040 
1041 	/*
1042 	 * We must provide a consistent atime and mtime for snapshots
1043 	 * so people can do a 'tar cf - ... | md5' on them and get
1044 	 * consistent results.
1045 	 */
1046 	if (ip->flags & HAMMER_INODE_RO) {
1047 		hammer_time_to_timespec(ip->ino_data.ctime, &vap->va_atime);
1048 		hammer_time_to_timespec(ip->ino_data.ctime, &vap->va_mtime);
1049 	} else {
1050 		hammer_time_to_timespec(ip->ino_data.atime, &vap->va_atime);
1051 		hammer_time_to_timespec(ip->ino_data.mtime, &vap->va_mtime);
1052 	}
1053 	hammer_time_to_timespec(ip->ino_data.ctime, &vap->va_ctime);
1054 	vap->va_flags = ip->ino_data.uflags;
1055 	vap->va_gen = 1;	/* hammer inums are unique for all time */
1056 	vap->va_blocksize = HAMMER_BUFSIZE;
1057 	if (ip->ino_data.size >= HAMMER_XDEMARC) {
1058 		vap->va_bytes = (ip->ino_data.size + HAMMER_XBUFMASK64) &
1059 				~HAMMER_XBUFMASK64;
1060 	} else if (ip->ino_data.size > HAMMER_HBUFSIZE) {
1061 		vap->va_bytes = (ip->ino_data.size + HAMMER_BUFMASK64) &
1062 				~HAMMER_BUFMASK64;
1063 	} else {
1064 		vap->va_bytes = (ip->ino_data.size + 15) & ~15;
1065 	}
1066 
1067 	vap->va_type = hammer_get_vnode_type(ip->ino_data.obj_type);
1068 	vap->va_filerev = 0;	/* XXX */
1069 	vap->va_uid_uuid = ip->ino_data.uid;
1070 	vap->va_gid_uuid = ip->ino_data.gid;
1071 	vap->va_fsid_uuid = ip->hmp->fsid;
1072 	vap->va_vaflags = VA_UID_UUID_VALID | VA_GID_UUID_VALID |
1073 			  VA_FSID_UUID_VALID;
1074 
1075 	switch (ip->ino_data.obj_type) {
1076 	case HAMMER_OBJTYPE_CDEV:
1077 	case HAMMER_OBJTYPE_BDEV:
1078 		vap->va_rmajor = ip->ino_data.rmajor;
1079 		vap->va_rminor = ip->ino_data.rminor;
1080 		break;
1081 	default:
1082 		break;
1083 	}
1084 	hammer_unlock(&ip->lock);
1085 	return(0);
1086 }
1087 
1088 /*
1089  * hammer_vop_nresolve { nch, dvp, cred }
1090  *
1091  * Locate the requested directory entry.
1092  */
1093 static
1094 int
1095 hammer_vop_nresolve(struct vop_nresolve_args *ap)
1096 {
1097 	struct hammer_transaction trans;
1098 	struct namecache *ncp;
1099 	hammer_mount_t hmp;
1100 	hammer_inode_t dip;
1101 	hammer_inode_t ip;
1102 	hammer_tid_t asof;
1103 	struct hammer_cursor cursor;
1104 	struct vnode *vp;
1105 	int64_t namekey;
1106 	int error;
1107 	int i;
1108 	int nlen;
1109 	int flags;
1110 	int ispfs;
1111 	int64_t obj_id;
1112 	uint32_t localization;
1113 	uint32_t max_iterations;
1114 
1115 	/*
1116 	 * Misc initialization, plus handle as-of name extensions.  Look for
1117 	 * the '@@' extension.  Note that as-of files and directories cannot
1118 	 * be modified.
1119 	 */
1120 	dip = VTOI(ap->a_dvp);
1121 	ncp = ap->a_nch->ncp;
1122 	asof = dip->obj_asof;
1123 	localization = dip->obj_localization;	/* for code consistency */
1124 	nlen = ncp->nc_nlen;
1125 	flags = dip->flags & HAMMER_INODE_RO;
1126 	ispfs = 0;
1127 	hmp = dip->hmp;
1128 
1129 	lwkt_gettoken(&hmp->fs_token);
1130 	hammer_simple_transaction(&trans, hmp);
1131 	++hammer_stats_file_iopsr;
1132 
1133 	for (i = 0; i < nlen; ++i) {
1134 		if (ncp->nc_name[i] == '@' && ncp->nc_name[i+1] == '@') {
1135 			error = hammer_str_to_tid(ncp->nc_name + i + 2,
1136 						  &ispfs, &asof, &localization);
1137 			if (error != 0) {
1138 				i = nlen;
1139 				break;
1140 			}
1141 			if (asof != HAMMER_MAX_TID)
1142 				flags |= HAMMER_INODE_RO;
1143 			break;
1144 		}
1145 	}
1146 	nlen = i;
1147 
1148 	/*
1149 	 * If this is a PFS softlink we dive into the PFS
1150 	 */
1151 	if (ispfs && nlen == 0) {
1152 		ip = hammer_get_inode(&trans, dip, HAMMER_OBJID_ROOT,
1153 				      asof, localization,
1154 				      flags, &error);
1155 		if (error == 0) {
1156 			error = hammer_get_vnode(ip, &vp);
1157 			hammer_rel_inode(ip, 0);
1158 		} else {
1159 			vp = NULL;
1160 		}
1161 		if (error == 0) {
1162 			vn_unlock(vp);
1163 			cache_setvp(ap->a_nch, vp);
1164 			vrele(vp);
1165 		}
1166 		goto done;
1167 	}
1168 
1169 	/*
1170 	 * If there is no path component the time extension is relative to dip.
1171 	 * e.g. "fubar/@@<snapshot>"
1172 	 *
1173 	 * "." is handled by the kernel, but ".@@<snapshot>" is not.
1174 	 * e.g. "fubar/.@@<snapshot>"
1175 	 *
1176 	 * ".." is handled by the kernel.  We do not currently handle
1177 	 * "..@<snapshot>".
1178 	 */
1179 	if (nlen == 0 || (nlen == 1 && ncp->nc_name[0] == '.')) {
1180 		ip = hammer_get_inode(&trans, dip, dip->obj_id,
1181 				      asof, dip->obj_localization,
1182 				      flags, &error);
1183 		if (error == 0) {
1184 			error = hammer_get_vnode(ip, &vp);
1185 			hammer_rel_inode(ip, 0);
1186 		} else {
1187 			vp = NULL;
1188 		}
1189 		if (error == 0) {
1190 			vn_unlock(vp);
1191 			cache_setvp(ap->a_nch, vp);
1192 			vrele(vp);
1193 		}
1194 		goto done;
1195 	}
1196 
1197 	/*
1198 	 * Calculate the namekey and setup the key range for the scan.  This
1199 	 * works kinda like a chained hash table where the lower 32 bits
1200 	 * of the namekey synthesize the chain.
1201 	 *
1202 	 * The key range is inclusive of both key_beg and key_end.
1203 	 */
1204 	namekey = hammer_direntry_namekey(dip, ncp->nc_name, nlen,
1205 					   &max_iterations);
1206 
1207 	error = hammer_init_cursor(&trans, &cursor, &dip->cache[1], dip);
1208 	cursor.key_beg.localization = dip->obj_localization |
1209 				      hammer_dir_localization(dip);
1210         cursor.key_beg.obj_id = dip->obj_id;
1211 	cursor.key_beg.key = namekey;
1212         cursor.key_beg.create_tid = 0;
1213         cursor.key_beg.delete_tid = 0;
1214         cursor.key_beg.rec_type = HAMMER_RECTYPE_DIRENTRY;
1215         cursor.key_beg.obj_type = 0;
1216 
1217 	cursor.key_end = cursor.key_beg;
1218 	cursor.key_end.key += max_iterations;
1219 	cursor.asof = asof;
1220 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF;
1221 
1222 	/*
1223 	 * Scan all matching records (the chain), locate the one matching
1224 	 * the requested path component.
1225 	 *
1226 	 * The hammer_ip_*() functions merge in-memory records with on-disk
1227 	 * records for the purposes of the search.
1228 	 */
1229 	obj_id = 0;
1230 	localization = HAMMER_DEF_LOCALIZATION;
1231 
1232 	if (error == 0) {
1233 		error = hammer_ip_first(&cursor);
1234 		while (error == 0) {
1235 			error = hammer_ip_resolve_data(&cursor);
1236 			if (error)
1237 				break;
1238 			if (nlen == cursor.leaf->data_len - HAMMER_ENTRY_NAME_OFF &&
1239 			    bcmp(ncp->nc_name, cursor.data->entry.name, nlen) == 0) {
1240 				obj_id = cursor.data->entry.obj_id;
1241 				localization = cursor.data->entry.localization;
1242 				break;
1243 			}
1244 			error = hammer_ip_next(&cursor);
1245 		}
1246 	}
1247 	hammer_done_cursor(&cursor);
1248 
1249 	/*
1250 	 * Lookup the obj_id.  This should always succeed.  If it does not
1251 	 * the filesystem may be damaged and we return a dummy inode.
1252 	 */
1253 	if (error == 0) {
1254 		ip = hammer_get_inode(&trans, dip, obj_id,
1255 				      asof, localization,
1256 				      flags, &error);
1257 		if (error == ENOENT) {
1258 			hkprintf("WARNING: Missing inode for dirent \"%s\"\n"
1259 				"\tobj_id = %016jx, asof=%016jx, lo=%08x\n",
1260 				ncp->nc_name,
1261 				(intmax_t)obj_id, (intmax_t)asof,
1262 				localization);
1263 			error = 0;
1264 			ip = hammer_get_dummy_inode(&trans, dip, obj_id,
1265 						    asof, localization,
1266 						    flags, &error);
1267 		}
1268 		if (error == 0) {
1269 			error = hammer_get_vnode(ip, &vp);
1270 			hammer_rel_inode(ip, 0);
1271 		} else {
1272 			vp = NULL;
1273 		}
1274 		if (error == 0) {
1275 			vn_unlock(vp);
1276 			cache_setvp(ap->a_nch, vp);
1277 			vrele(vp);
1278 		}
1279 	} else if (error == ENOENT) {
1280 		cache_setvp(ap->a_nch, NULL);
1281 	}
1282 done:
1283 	hammer_done_transaction(&trans);
1284 	lwkt_reltoken(&hmp->fs_token);
1285 	return (error);
1286 }
1287 
1288 /*
1289  * hammer_vop_nlookupdotdot { dvp, vpp, cred }
1290  *
1291  * Locate the parent directory of a directory vnode.
1292  *
1293  * dvp is referenced but not locked.  *vpp must be returned referenced and
1294  * locked.  A parent_obj_id of 0 indicates that we are at the root.
1295  *
1296  * NOTE: as-of sequences are not linked into the directory structure.  If
1297  * we are at the root with a different asof then the mount point, reload
1298  * the same directory with the mount point's asof.   I'm not sure what this
1299  * will do to NFS.  We encode ASOF stamps in NFS file handles so it might not
1300  * get confused, but it hasn't been tested.
1301  */
1302 static
1303 int
1304 hammer_vop_nlookupdotdot(struct vop_nlookupdotdot_args *ap)
1305 {
1306 	struct hammer_transaction trans;
1307 	hammer_inode_t dip;
1308 	hammer_inode_t ip;
1309 	hammer_mount_t hmp;
1310 	int64_t parent_obj_id;
1311 	uint32_t parent_obj_localization;
1312 	hammer_tid_t asof;
1313 	int error;
1314 
1315 	dip = VTOI(ap->a_dvp);
1316 	asof = dip->obj_asof;
1317 	hmp = dip->hmp;
1318 
1319 	/*
1320 	 * Whos are parent?  This could be the root of a pseudo-filesystem
1321 	 * whos parent is in another localization domain.
1322 	 */
1323 	lwkt_gettoken(&hmp->fs_token);
1324 	parent_obj_id = dip->ino_data.parent_obj_id;
1325 	if (dip->obj_id == HAMMER_OBJID_ROOT)
1326 		parent_obj_localization = HAMMER_DEF_LOCALIZATION;
1327 	else
1328 		parent_obj_localization = dip->obj_localization;
1329 
1330 	/*
1331 	 * It's probably a PFS root when dip->ino_data.parent_obj_id is 0.
1332 	 */
1333 	if (parent_obj_id == 0) {
1334 		if (dip->obj_id == HAMMER_OBJID_ROOT &&
1335 		   asof != hmp->asof) {
1336 			parent_obj_id = dip->obj_id;
1337 			asof = hmp->asof;
1338 			*ap->a_fakename = kmalloc(19, M_TEMP, M_WAITOK);
1339 			ksnprintf(*ap->a_fakename, 19, "0x%016jx",
1340 				  (intmax_t)dip->obj_asof);
1341 		} else {
1342 			*ap->a_vpp = NULL;
1343 			lwkt_reltoken(&hmp->fs_token);
1344 			return ENOENT;
1345 		}
1346 	}
1347 
1348 	hammer_simple_transaction(&trans, hmp);
1349 	++hammer_stats_file_iopsr;
1350 
1351 	ip = hammer_get_inode(&trans, dip, parent_obj_id,
1352 			      asof, parent_obj_localization,
1353 			      dip->flags, &error);
1354 	if (ip) {
1355 		error = hammer_get_vnode(ip, ap->a_vpp);
1356 		hammer_rel_inode(ip, 0);
1357 	} else {
1358 		*ap->a_vpp = NULL;
1359 	}
1360 	hammer_done_transaction(&trans);
1361 	lwkt_reltoken(&hmp->fs_token);
1362 	return (error);
1363 }
1364 
1365 /*
1366  * hammer_vop_nlink { nch, dvp, vp, cred }
1367  */
1368 static
1369 int
1370 hammer_vop_nlink(struct vop_nlink_args *ap)
1371 {
1372 	struct hammer_transaction trans;
1373 	hammer_inode_t dip;
1374 	hammer_inode_t ip;
1375 	struct nchandle *nch;
1376 	hammer_mount_t hmp;
1377 	int error;
1378 
1379 	if (ap->a_dvp->v_mount != ap->a_vp->v_mount)
1380 		return(EXDEV);
1381 
1382 	nch = ap->a_nch;
1383 	dip = VTOI(ap->a_dvp);
1384 	ip = VTOI(ap->a_vp);
1385 	hmp = dip->hmp;
1386 
1387 	if (dip->obj_localization != ip->obj_localization)
1388 		return(EXDEV);
1389 
1390 	if (dip->flags & HAMMER_INODE_RO)
1391 		return (EROFS);
1392 	if (ip->flags & HAMMER_INODE_RO)
1393 		return (EROFS);
1394 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
1395 		return (error);
1396 
1397 	/*
1398 	 * Create a transaction to cover the operations we perform.
1399 	 */
1400 	lwkt_gettoken(&hmp->fs_token);
1401 	hammer_start_transaction(&trans, hmp);
1402 	++hammer_stats_file_iopsw;
1403 
1404 	/*
1405 	 * Add the filesystem object to the directory.  Note that neither
1406 	 * dip nor ip are referenced or locked, but their vnodes are
1407 	 * referenced.  This function will bump the inode's link count.
1408 	 */
1409 	error = hammer_ip_add_direntry(&trans, dip,
1410 					nch->ncp->nc_name, nch->ncp->nc_nlen,
1411 					ip);
1412 
1413 	/*
1414 	 * Finish up.
1415 	 */
1416 	if (error == 0) {
1417 		cache_setunresolved(nch);
1418 		cache_setvp(nch, ap->a_vp);
1419 	}
1420 	hammer_done_transaction(&trans);
1421 	hammer_knote(ap->a_vp, NOTE_LINK);
1422 	hammer_knote(ap->a_dvp, NOTE_WRITE);
1423 	lwkt_reltoken(&hmp->fs_token);
1424 	return (error);
1425 }
1426 
1427 /*
1428  * hammer_vop_nmkdir { nch, dvp, vpp, cred, vap }
1429  *
1430  * The operating system has already ensured that the directory entry
1431  * does not exist and done all appropriate namespace locking.
1432  */
1433 static
1434 int
1435 hammer_vop_nmkdir(struct vop_nmkdir_args *ap)
1436 {
1437 	struct hammer_transaction trans;
1438 	hammer_inode_t dip;
1439 	hammer_inode_t nip;
1440 	struct nchandle *nch;
1441 	hammer_mount_t hmp;
1442 	int error;
1443 
1444 	nch = ap->a_nch;
1445 	dip = VTOI(ap->a_dvp);
1446 	hmp = dip->hmp;
1447 
1448 	if (dip->flags & HAMMER_INODE_RO)
1449 		return (EROFS);
1450 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
1451 		return (error);
1452 
1453 	/*
1454 	 * Create a transaction to cover the operations we perform.
1455 	 */
1456 	lwkt_gettoken(&hmp->fs_token);
1457 	hammer_start_transaction(&trans, hmp);
1458 	++hammer_stats_file_iopsw;
1459 
1460 	/*
1461 	 * Create a new filesystem object of the requested type.  The
1462 	 * returned inode will be referenced but not locked.
1463 	 */
1464 	error = hammer_create_inode(&trans, ap->a_vap, ap->a_cred,
1465 				    dip, nch->ncp->nc_name, nch->ncp->nc_nlen,
1466 				    NULL, &nip);
1467 	if (error) {
1468 		hammer_done_transaction(&trans);
1469 		*ap->a_vpp = NULL;
1470 		lwkt_reltoken(&hmp->fs_token);
1471 		return (error);
1472 	}
1473 	/*
1474 	 * Add the new filesystem object to the directory.  This will also
1475 	 * bump the inode's link count.
1476 	 */
1477 	error = hammer_ip_add_direntry(&trans, dip,
1478 					nch->ncp->nc_name, nch->ncp->nc_nlen,
1479 					nip);
1480 	if (error)
1481 		hkprintf("hammer_mkdir (add) error %d\n", error);
1482 
1483 	/*
1484 	 * Finish up.
1485 	 */
1486 	if (error) {
1487 		hammer_rel_inode(nip, 0);
1488 		*ap->a_vpp = NULL;
1489 	} else {
1490 		error = hammer_get_vnode(nip, ap->a_vpp);
1491 		hammer_rel_inode(nip, 0);
1492 		if (error == 0) {
1493 			cache_setunresolved(ap->a_nch);
1494 			cache_setvp(ap->a_nch, *ap->a_vpp);
1495 		}
1496 	}
1497 	hammer_done_transaction(&trans);
1498 	if (error == 0)
1499 		hammer_knote(ap->a_dvp, NOTE_WRITE | NOTE_LINK);
1500 	lwkt_reltoken(&hmp->fs_token);
1501 	return (error);
1502 }
1503 
1504 /*
1505  * hammer_vop_nmknod { nch, dvp, vpp, cred, vap }
1506  *
1507  * The operating system has already ensured that the directory entry
1508  * does not exist and done all appropriate namespace locking.
1509  */
1510 static
1511 int
1512 hammer_vop_nmknod(struct vop_nmknod_args *ap)
1513 {
1514 	struct hammer_transaction trans;
1515 	hammer_inode_t dip;
1516 	hammer_inode_t nip;
1517 	struct nchandle *nch;
1518 	hammer_mount_t hmp;
1519 	int error;
1520 
1521 	nch = ap->a_nch;
1522 	dip = VTOI(ap->a_dvp);
1523 	hmp = dip->hmp;
1524 
1525 	if (dip->flags & HAMMER_INODE_RO)
1526 		return (EROFS);
1527 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
1528 		return (error);
1529 
1530 	/*
1531 	 * Create a transaction to cover the operations we perform.
1532 	 */
1533 	lwkt_gettoken(&hmp->fs_token);
1534 	hammer_start_transaction(&trans, hmp);
1535 	++hammer_stats_file_iopsw;
1536 
1537 	/*
1538 	 * Create a new filesystem object of the requested type.  The
1539 	 * returned inode will be referenced but not locked.
1540 	 *
1541 	 * If mknod specifies a directory a pseudo-fs is created.
1542 	 */
1543 	error = hammer_create_inode(&trans, ap->a_vap, ap->a_cred,
1544 				    dip, nch->ncp->nc_name, nch->ncp->nc_nlen,
1545 				    NULL, &nip);
1546 	if (error) {
1547 		hammer_done_transaction(&trans);
1548 		*ap->a_vpp = NULL;
1549 		lwkt_reltoken(&hmp->fs_token);
1550 		return (error);
1551 	}
1552 
1553 	/*
1554 	 * Add the new filesystem object to the directory.  This will also
1555 	 * bump the inode's link count.
1556 	 */
1557 	error = hammer_ip_add_direntry(&trans, dip,
1558 					nch->ncp->nc_name, nch->ncp->nc_nlen,
1559 					nip);
1560 
1561 	/*
1562 	 * Finish up.
1563 	 */
1564 	if (error) {
1565 		hammer_rel_inode(nip, 0);
1566 		*ap->a_vpp = NULL;
1567 	} else {
1568 		error = hammer_get_vnode(nip, ap->a_vpp);
1569 		hammer_rel_inode(nip, 0);
1570 		if (error == 0) {
1571 			cache_setunresolved(ap->a_nch);
1572 			cache_setvp(ap->a_nch, *ap->a_vpp);
1573 		}
1574 	}
1575 	hammer_done_transaction(&trans);
1576 	if (error == 0)
1577 		hammer_knote(ap->a_dvp, NOTE_WRITE);
1578 	lwkt_reltoken(&hmp->fs_token);
1579 	return (error);
1580 }
1581 
1582 /*
1583  * hammer_vop_open { vp, mode, cred, fp }
1584  *
1585  * MPSAFE (does not require fs_token)
1586  */
1587 static
1588 int
1589 hammer_vop_open(struct vop_open_args *ap)
1590 {
1591 	hammer_inode_t ip;
1592 
1593 	++hammer_stats_file_iopsr;
1594 	ip = VTOI(ap->a_vp);
1595 
1596 	if ((ap->a_mode & FWRITE) && (ip->flags & HAMMER_INODE_RO))
1597 		return (EROFS);
1598 	return(vop_stdopen(ap));
1599 }
1600 
1601 /*
1602  * hammer_vop_print { vp }
1603  */
1604 static
1605 int
1606 hammer_vop_print(struct vop_print_args *ap)
1607 {
1608 	return EOPNOTSUPP;
1609 }
1610 
1611 /*
1612  * hammer_vop_readdir { vp, uio, cred, *eofflag, *ncookies, off_t **cookies }
1613  */
1614 static
1615 int
1616 hammer_vop_readdir(struct vop_readdir_args *ap)
1617 {
1618 	struct hammer_transaction trans;
1619 	struct hammer_cursor cursor;
1620 	hammer_inode_t ip;
1621 	hammer_mount_t hmp;
1622 	struct uio *uio;
1623 	hammer_base_elm_t base;
1624 	int error;
1625 	int cookie_index;
1626 	int ncookies;
1627 	off_t *cookies;
1628 	off_t saveoff;
1629 	int r;
1630 	int dtype;
1631 
1632 	++hammer_stats_file_iopsr;
1633 	ip = VTOI(ap->a_vp);
1634 	uio = ap->a_uio;
1635 	saveoff = uio->uio_offset;
1636 	hmp = ip->hmp;
1637 
1638 	if (ap->a_ncookies) {
1639 		ncookies = uio->uio_resid / 16 + 1;
1640 		if (ncookies > 1024)
1641 			ncookies = 1024;
1642 		cookies = kmalloc(ncookies * sizeof(off_t), M_TEMP, M_WAITOK);
1643 		cookie_index = 0;
1644 	} else {
1645 		ncookies = -1;
1646 		cookies = NULL;
1647 		cookie_index = 0;
1648 	}
1649 
1650 	lwkt_gettoken(&hmp->fs_token);
1651 	hammer_simple_transaction(&trans, hmp);
1652 
1653 	/*
1654 	 * Handle artificial entries
1655 	 *
1656 	 * It should be noted that the minimum value for a directory
1657 	 * hash key on-media is 0x0000000100000000, so we can use anything
1658 	 * less then that to represent our 'special' key space.
1659 	 */
1660 	error = 0;
1661 	if (saveoff == 0) {
1662 		r = vop_write_dirent(&error, uio, ip->obj_id, DT_DIR, 1, ".");
1663 		if (r)
1664 			goto done;
1665 		if (cookies)
1666 			cookies[cookie_index] = saveoff;
1667 		++saveoff;
1668 		++cookie_index;
1669 		if (cookie_index == ncookies)
1670 			goto done;
1671 	}
1672 	if (saveoff == 1) {
1673 		if (ip->ino_data.parent_obj_id) {
1674 			r = vop_write_dirent(&error, uio,
1675 					     ip->ino_data.parent_obj_id,
1676 					     DT_DIR, 2, "..");
1677 		} else {
1678 			r = vop_write_dirent(&error, uio,
1679 					     ip->obj_id, DT_DIR, 2, "..");
1680 		}
1681 		if (r)
1682 			goto done;
1683 		if (cookies)
1684 			cookies[cookie_index] = saveoff;
1685 		++saveoff;
1686 		++cookie_index;
1687 		if (cookie_index == ncookies)
1688 			goto done;
1689 	}
1690 
1691 	/*
1692 	 * Key range (begin and end inclusive) to scan.  Directory keys
1693 	 * directly translate to a 64 bit 'seek' position.
1694 	 */
1695 	hammer_init_cursor(&trans, &cursor, &ip->cache[1], ip);
1696 	cursor.key_beg.localization = ip->obj_localization |
1697 				      hammer_dir_localization(ip);
1698 	cursor.key_beg.obj_id = ip->obj_id;
1699 	cursor.key_beg.create_tid = 0;
1700 	cursor.key_beg.delete_tid = 0;
1701         cursor.key_beg.rec_type = HAMMER_RECTYPE_DIRENTRY;
1702 	cursor.key_beg.obj_type = 0;
1703 	cursor.key_beg.key = saveoff;
1704 
1705 	cursor.key_end = cursor.key_beg;
1706 	cursor.key_end.key = HAMMER_MAX_KEY;
1707 	cursor.asof = ip->obj_asof;
1708 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF;
1709 
1710 	error = hammer_ip_first(&cursor);
1711 
1712 	while (error == 0) {
1713 		error = hammer_ip_resolve_data(&cursor);
1714 		if (error)
1715 			break;
1716 		base = &cursor.leaf->base;
1717 		saveoff = base->key;
1718 		KKASSERT(cursor.leaf->data_len > HAMMER_ENTRY_NAME_OFF);
1719 
1720 		if (base->obj_id != ip->obj_id)
1721 			hpanic("bad record at %p", cursor.node);
1722 
1723 		dtype = hammer_get_dtype(cursor.leaf->base.obj_type);
1724 		r = vop_write_dirent(
1725 			     &error, uio, cursor.data->entry.obj_id,
1726 			     dtype,
1727 			     cursor.leaf->data_len - HAMMER_ENTRY_NAME_OFF ,
1728 			     (void *)cursor.data->entry.name);
1729 		if (r)
1730 			break;
1731 		++saveoff;
1732 		if (cookies)
1733 			cookies[cookie_index] = base->key;
1734 		++cookie_index;
1735 		if (cookie_index == ncookies)
1736 			break;
1737 		error = hammer_ip_next(&cursor);
1738 	}
1739 	hammer_done_cursor(&cursor);
1740 
1741 done:
1742 	hammer_done_transaction(&trans);
1743 
1744 	if (ap->a_eofflag)
1745 		*ap->a_eofflag = (error == ENOENT);
1746 	uio->uio_offset = saveoff;
1747 	if (error && cookie_index == 0) {
1748 		if (error == ENOENT)
1749 			error = 0;
1750 		if (cookies) {
1751 			kfree(cookies, M_TEMP);
1752 			*ap->a_ncookies = 0;
1753 			*ap->a_cookies = NULL;
1754 		}
1755 	} else {
1756 		if (error == ENOENT)
1757 			error = 0;
1758 		if (cookies) {
1759 			*ap->a_ncookies = cookie_index;
1760 			*ap->a_cookies = cookies;
1761 		}
1762 	}
1763 	lwkt_reltoken(&hmp->fs_token);
1764 	return(error);
1765 }
1766 
1767 /*
1768  * hammer_vop_readlink { vp, uio, cred }
1769  */
1770 static
1771 int
1772 hammer_vop_readlink(struct vop_readlink_args *ap)
1773 {
1774 	struct hammer_transaction trans;
1775 	struct hammer_cursor cursor;
1776 	hammer_inode_t ip;
1777 	hammer_mount_t hmp;
1778 	char buf[32];
1779 	uint32_t localization;
1780 	hammer_pseudofs_inmem_t pfsm;
1781 	int error;
1782 
1783 	ip = VTOI(ap->a_vp);
1784 	hmp = ip->hmp;
1785 
1786 	lwkt_gettoken(&hmp->fs_token);
1787 
1788 	/*
1789 	 * Shortcut if the symlink data was stuffed into ino_data.
1790 	 *
1791 	 * Also expand special "@@PFS%05d" softlinks (expansion only
1792 	 * occurs for non-historical (current) accesses made from the
1793 	 * primary filesystem).
1794 	 *
1795 	 * Note that userspace hammer command does not allow users to
1796 	 * create a @@PFS softlink under an existing other PFS (id!=0)
1797 	 * so the ip localization here for @@PFS softlink is always 0.
1798 	 */
1799 	if (ip->ino_data.size <= HAMMER_INODE_BASESYMLEN) {
1800 		char *ptr;
1801 		int bytes;
1802 
1803 		ptr = ip->ino_data.ext.symlink;
1804 		bytes = (int)ip->ino_data.size;
1805 		if (bytes == 10 &&
1806 		    ip->obj_asof == HAMMER_MAX_TID &&
1807 		    ip->obj_localization == HAMMER_DEF_LOCALIZATION &&
1808 		    strncmp(ptr, "@@PFS", 5) == 0) {
1809 			hammer_simple_transaction(&trans, hmp);
1810 			bcopy(ptr + 5, buf, 5);
1811 			buf[5] = 0;
1812 			localization = pfs_to_lo(strtoul(buf, NULL, 10));
1813 			pfsm = hammer_load_pseudofs(&trans, localization,
1814 						    &error);
1815 			if (error == 0) {
1816 				if (hammer_is_pfs_slave(&pfsm->pfsd)) {
1817 					/* vap->va_size == 26 */
1818 					ksnprintf(buf, sizeof(buf),
1819 						  "@@0x%016jx:%05d",
1820 						  (intmax_t)pfsm->pfsd.sync_end_tid,
1821 						  lo_to_pfs(localization));
1822 				} else {
1823 					/* vap->va_size == 10 */
1824 					ksnprintf(buf, sizeof(buf),
1825 						  "@@-1:%05d",
1826 						  lo_to_pfs(localization));
1827 				}
1828 				ptr = buf;
1829 				bytes = strlen(buf);
1830 			}
1831 			if (pfsm)
1832 				hammer_rel_pseudofs(hmp, pfsm);
1833 			hammer_done_transaction(&trans);
1834 		}
1835 		error = uiomove(ptr, bytes, ap->a_uio);
1836 		lwkt_reltoken(&hmp->fs_token);
1837 		return(error);
1838 	}
1839 
1840 	/*
1841 	 * Long version
1842 	 */
1843 	hammer_simple_transaction(&trans, hmp);
1844 	++hammer_stats_file_iopsr;
1845 	hammer_init_cursor(&trans, &cursor, &ip->cache[1], ip);
1846 
1847 	/*
1848 	 * Key range (begin and end inclusive) to scan.  Directory keys
1849 	 * directly translate to a 64 bit 'seek' position.
1850 	 */
1851 	cursor.key_beg.localization = ip->obj_localization |
1852 				      HAMMER_LOCALIZE_MISC;
1853 	cursor.key_beg.obj_id = ip->obj_id;
1854 	cursor.key_beg.create_tid = 0;
1855 	cursor.key_beg.delete_tid = 0;
1856         cursor.key_beg.rec_type = HAMMER_RECTYPE_FIX;
1857 	cursor.key_beg.obj_type = 0;
1858 	cursor.key_beg.key = HAMMER_FIXKEY_SYMLINK;
1859 	cursor.asof = ip->obj_asof;
1860 	cursor.flags |= HAMMER_CURSOR_ASOF;
1861 
1862 	error = hammer_ip_lookup(&cursor);
1863 	if (error == 0) {
1864 		error = hammer_ip_resolve_data(&cursor);
1865 		if (error == 0) {
1866 			KKASSERT(cursor.leaf->data_len >=
1867 				 HAMMER_SYMLINK_NAME_OFF);
1868 			error = uiomove(cursor.data->symlink.name,
1869 					cursor.leaf->data_len -
1870 						HAMMER_SYMLINK_NAME_OFF,
1871 					ap->a_uio);
1872 		}
1873 	}
1874 	hammer_done_cursor(&cursor);
1875 	hammer_done_transaction(&trans);
1876 	lwkt_reltoken(&hmp->fs_token);
1877 	return(error);
1878 }
1879 
1880 /*
1881  * hammer_vop_nremove { nch, dvp, cred }
1882  */
1883 static
1884 int
1885 hammer_vop_nremove(struct vop_nremove_args *ap)
1886 {
1887 	struct hammer_transaction trans;
1888 	hammer_inode_t dip;
1889 	hammer_mount_t hmp;
1890 	int error;
1891 
1892 	dip = VTOI(ap->a_dvp);
1893 	hmp = dip->hmp;
1894 
1895 	if (hammer_nohistory(dip) == 0 &&
1896 	    (error = hammer_checkspace(hmp, HAMMER_CHKSPC_REMOVE)) != 0) {
1897 		return (error);
1898 	}
1899 
1900 	lwkt_gettoken(&hmp->fs_token);
1901 	hammer_start_transaction(&trans, hmp);
1902 	++hammer_stats_file_iopsw;
1903 	error = hammer_dounlink(&trans, ap->a_nch, ap->a_dvp, ap->a_cred, 0, 0);
1904 	hammer_done_transaction(&trans);
1905 	if (error == 0)
1906 		hammer_knote(ap->a_dvp, NOTE_WRITE);
1907 	lwkt_reltoken(&hmp->fs_token);
1908 	return (error);
1909 }
1910 
1911 /*
1912  * hammer_vop_nrename { fnch, tnch, fdvp, tdvp, cred }
1913  */
1914 static
1915 int
1916 hammer_vop_nrename(struct vop_nrename_args *ap)
1917 {
1918 	struct hammer_transaction trans;
1919 	struct namecache *fncp;
1920 	struct namecache *tncp;
1921 	hammer_inode_t fdip;
1922 	hammer_inode_t tdip;
1923 	hammer_inode_t ip;
1924 	hammer_mount_t hmp;
1925 	struct hammer_cursor cursor;
1926 	int64_t namekey;
1927 	uint32_t max_iterations;
1928 	int nlen, error;
1929 
1930 	if (ap->a_fdvp->v_mount != ap->a_tdvp->v_mount)
1931 		return(EXDEV);
1932 	if (ap->a_fdvp->v_mount != ap->a_fnch->ncp->nc_vp->v_mount)
1933 		return(EXDEV);
1934 
1935 	fdip = VTOI(ap->a_fdvp);
1936 	tdip = VTOI(ap->a_tdvp);
1937 	fncp = ap->a_fnch->ncp;
1938 	tncp = ap->a_tnch->ncp;
1939 	ip = VTOI(fncp->nc_vp);
1940 	KKASSERT(ip != NULL);
1941 
1942 	hmp = ip->hmp;
1943 
1944 	if (fdip->obj_localization != tdip->obj_localization)
1945 		return(EXDEV);
1946 	if (fdip->obj_localization != ip->obj_localization)
1947 		return(EXDEV);
1948 
1949 	if (fdip->flags & HAMMER_INODE_RO)
1950 		return (EROFS);
1951 	if (tdip->flags & HAMMER_INODE_RO)
1952 		return (EROFS);
1953 	if (ip->flags & HAMMER_INODE_RO)
1954 		return (EROFS);
1955 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
1956 		return (error);
1957 
1958 	lwkt_gettoken(&hmp->fs_token);
1959 	hammer_start_transaction(&trans, hmp);
1960 	++hammer_stats_file_iopsw;
1961 
1962 	/*
1963 	 * Remove tncp from the target directory and then link ip as
1964 	 * tncp. XXX pass trans to dounlink
1965 	 *
1966 	 * Force the inode sync-time to match the transaction so it is
1967 	 * in-sync with the creation of the target directory entry.
1968 	 */
1969 	error = hammer_dounlink(&trans, ap->a_tnch, ap->a_tdvp,
1970 				ap->a_cred, 0, -1);
1971 	if (error == 0 || error == ENOENT) {
1972 		error = hammer_ip_add_direntry(&trans, tdip,
1973 						tncp->nc_name, tncp->nc_nlen,
1974 						ip);
1975 		if (error == 0) {
1976 			ip->ino_data.parent_obj_id = tdip->obj_id;
1977 			ip->ino_data.ctime = trans.time;
1978 			hammer_modify_inode(&trans, ip, HAMMER_INODE_DDIRTY);
1979 		}
1980 	}
1981 	if (error)
1982 		goto failed; /* XXX */
1983 
1984 	/*
1985 	 * Locate the record in the originating directory and remove it.
1986 	 *
1987 	 * Calculate the namekey and setup the key range for the scan.  This
1988 	 * works kinda like a chained hash table where the lower 32 bits
1989 	 * of the namekey synthesize the chain.
1990 	 *
1991 	 * The key range is inclusive of both key_beg and key_end.
1992 	 */
1993 	namekey = hammer_direntry_namekey(fdip, fncp->nc_name, fncp->nc_nlen,
1994 					   &max_iterations);
1995 retry:
1996 	hammer_init_cursor(&trans, &cursor, &fdip->cache[1], fdip);
1997 	cursor.key_beg.localization = fdip->obj_localization |
1998 				      hammer_dir_localization(fdip);
1999         cursor.key_beg.obj_id = fdip->obj_id;
2000 	cursor.key_beg.key = namekey;
2001         cursor.key_beg.create_tid = 0;
2002         cursor.key_beg.delete_tid = 0;
2003         cursor.key_beg.rec_type = HAMMER_RECTYPE_DIRENTRY;
2004         cursor.key_beg.obj_type = 0;
2005 
2006 	cursor.key_end = cursor.key_beg;
2007 	cursor.key_end.key += max_iterations;
2008 	cursor.asof = fdip->obj_asof;
2009 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF;
2010 
2011 	/*
2012 	 * Scan all matching records (the chain), locate the one matching
2013 	 * the requested path component.
2014 	 *
2015 	 * The hammer_ip_*() functions merge in-memory records with on-disk
2016 	 * records for the purposes of the search.
2017 	 */
2018 	error = hammer_ip_first(&cursor);
2019 	while (error == 0) {
2020 		if (hammer_ip_resolve_data(&cursor) != 0)
2021 			break;
2022 		nlen = cursor.leaf->data_len - HAMMER_ENTRY_NAME_OFF;
2023 		KKASSERT(nlen > 0);
2024 		if (fncp->nc_nlen == nlen &&
2025 		    bcmp(fncp->nc_name, cursor.data->entry.name, nlen) == 0) {
2026 			break;
2027 		}
2028 		error = hammer_ip_next(&cursor);
2029 	}
2030 
2031 	/*
2032 	 * If all is ok we have to get the inode so we can adjust nlinks.
2033 	 *
2034 	 * WARNING: hammer_ip_del_direntry() may have to terminate the
2035 	 * cursor to avoid a recursion.  It's ok to call hammer_done_cursor()
2036 	 * twice.
2037 	 */
2038 	if (error == 0)
2039 		error = hammer_ip_del_direntry(&trans, &cursor, fdip, ip);
2040 
2041 	/*
2042 	 * XXX A deadlock here will break rename's atomicy for the purposes
2043 	 * of crash recovery.
2044 	 */
2045 	if (error == EDEADLK) {
2046 		hammer_done_cursor(&cursor);
2047 		goto retry;
2048 	}
2049 
2050 	/*
2051 	 * Cleanup and tell the kernel that the rename succeeded.
2052 	 *
2053 	 * NOTE: ip->vp, if non-NULL, cannot be directly referenced
2054 	 *	 without formally acquiring the vp since the vp might
2055 	 *	 have zero refs on it, or in the middle of a reclaim,
2056 	 *	 etc.
2057 	 */
2058         hammer_done_cursor(&cursor);
2059 	if (error == 0) {
2060 		cache_rename(ap->a_fnch, ap->a_tnch);
2061 		hammer_knote(ap->a_fdvp, NOTE_WRITE);
2062 		hammer_knote(ap->a_tdvp, NOTE_WRITE);
2063 		while (ip->vp) {
2064 			struct vnode *vp;
2065 
2066 			error = hammer_get_vnode(ip, &vp);
2067 			if (error == 0 && vp) {
2068 				vn_unlock(vp);
2069 				hammer_knote(ip->vp, NOTE_RENAME);
2070 				vrele(vp);
2071 				break;
2072 			}
2073 			hdkprintf("ip/vp race2 avoided\n");
2074 		}
2075 	}
2076 
2077 failed:
2078 	hammer_done_transaction(&trans);
2079 	lwkt_reltoken(&hmp->fs_token);
2080 	return (error);
2081 }
2082 
2083 /*
2084  * hammer_vop_nrmdir { nch, dvp, cred }
2085  */
2086 static
2087 int
2088 hammer_vop_nrmdir(struct vop_nrmdir_args *ap)
2089 {
2090 	struct hammer_transaction trans;
2091 	hammer_inode_t dip;
2092 	hammer_mount_t hmp;
2093 	int error;
2094 
2095 	dip = VTOI(ap->a_dvp);
2096 	hmp = dip->hmp;
2097 
2098 	if (hammer_nohistory(dip) == 0 &&
2099 	    (error = hammer_checkspace(hmp, HAMMER_CHKSPC_REMOVE)) != 0) {
2100 		return (error);
2101 	}
2102 
2103 	lwkt_gettoken(&hmp->fs_token);
2104 	hammer_start_transaction(&trans, hmp);
2105 	++hammer_stats_file_iopsw;
2106 	error = hammer_dounlink(&trans, ap->a_nch, ap->a_dvp, ap->a_cred, 0, 1);
2107 	hammer_done_transaction(&trans);
2108 	if (error == 0)
2109 		hammer_knote(ap->a_dvp, NOTE_WRITE | NOTE_LINK);
2110 	lwkt_reltoken(&hmp->fs_token);
2111 	return (error);
2112 }
2113 
2114 /*
2115  * hammer_vop_markatime { vp, cred }
2116  */
2117 static
2118 int
2119 hammer_vop_markatime(struct vop_markatime_args *ap)
2120 {
2121 	struct hammer_transaction trans;
2122 	hammer_inode_t ip;
2123 	hammer_mount_t hmp;
2124 
2125 	ip = VTOI(ap->a_vp);
2126 	if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY)
2127 		return (EROFS);
2128 	if (ip->flags & HAMMER_INODE_RO)
2129 		return (EROFS);
2130 	hmp = ip->hmp;
2131 	if (hmp->mp->mnt_flag & MNT_NOATIME)
2132 		return (0);
2133 	lwkt_gettoken(&hmp->fs_token);
2134 	hammer_start_transaction(&trans, hmp);
2135 	++hammer_stats_file_iopsw;
2136 
2137 	ip->ino_data.atime = trans.time;
2138 	hammer_modify_inode(&trans, ip, HAMMER_INODE_ATIME);
2139 	hammer_done_transaction(&trans);
2140 	hammer_knote(ap->a_vp, NOTE_ATTRIB);
2141 	lwkt_reltoken(&hmp->fs_token);
2142 	return (0);
2143 }
2144 
2145 /*
2146  * hammer_vop_setattr { vp, vap, cred }
2147  */
2148 static
2149 int
2150 hammer_vop_setattr(struct vop_setattr_args *ap)
2151 {
2152 	struct hammer_transaction trans;
2153 	hammer_inode_t ip;
2154 	struct vattr *vap;
2155 	hammer_mount_t hmp;
2156 	int modflags;
2157 	int error;
2158 	int truncating;
2159 	int blksize;
2160 	int kflags;
2161 #if 0
2162 	int64_t aligned_size;
2163 #endif
2164 	uint32_t flags;
2165 
2166 	vap = ap->a_vap;
2167 	ip = ap->a_vp->v_data;
2168 	modflags = 0;
2169 	kflags = 0;
2170 	hmp = ip->hmp;
2171 
2172 	if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY)
2173 		return(EROFS);
2174 	if (ip->flags & HAMMER_INODE_RO)
2175 		return (EROFS);
2176 	if (hammer_nohistory(ip) == 0 &&
2177 	    (error = hammer_checkspace(hmp, HAMMER_CHKSPC_REMOVE)) != 0) {
2178 		return (error);
2179 	}
2180 
2181 	lwkt_gettoken(&hmp->fs_token);
2182 	hammer_start_transaction(&trans, hmp);
2183 	++hammer_stats_file_iopsw;
2184 	error = 0;
2185 
2186 	if (vap->va_flags != VNOVAL) {
2187 		flags = ip->ino_data.uflags;
2188 		error = vop_helper_setattr_flags(&flags, vap->va_flags,
2189 					 hammer_to_unix_xid(&ip->ino_data.uid),
2190 					 ap->a_cred);
2191 		if (error == 0) {
2192 			if (ip->ino_data.uflags != flags) {
2193 				ip->ino_data.uflags = flags;
2194 				ip->ino_data.ctime = trans.time;
2195 				modflags |= HAMMER_INODE_DDIRTY;
2196 				kflags |= NOTE_ATTRIB;
2197 			}
2198 			if (ip->ino_data.uflags & (IMMUTABLE | APPEND)) {
2199 				error = 0;
2200 				goto done;
2201 			}
2202 		}
2203 		goto done;
2204 	}
2205 	if (ip->ino_data.uflags & (IMMUTABLE | APPEND)) {
2206 		error = EPERM;
2207 		goto done;
2208 	}
2209 	if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) {
2210 		mode_t cur_mode = ip->ino_data.mode;
2211 		uid_t cur_uid = hammer_to_unix_xid(&ip->ino_data.uid);
2212 		gid_t cur_gid = hammer_to_unix_xid(&ip->ino_data.gid);
2213 		uuid_t uuid_uid;
2214 		uuid_t uuid_gid;
2215 
2216 		error = vop_helper_chown(ap->a_vp, vap->va_uid, vap->va_gid,
2217 					 ap->a_cred,
2218 					 &cur_uid, &cur_gid, &cur_mode);
2219 		if (error == 0) {
2220 			hammer_guid_to_uuid(&uuid_uid, cur_uid);
2221 			hammer_guid_to_uuid(&uuid_gid, cur_gid);
2222 			if (bcmp(&uuid_uid, &ip->ino_data.uid,
2223 				 sizeof(uuid_uid)) ||
2224 			    bcmp(&uuid_gid, &ip->ino_data.gid,
2225 				 sizeof(uuid_gid)) ||
2226 			    ip->ino_data.mode != cur_mode) {
2227 				ip->ino_data.uid = uuid_uid;
2228 				ip->ino_data.gid = uuid_gid;
2229 				ip->ino_data.mode = cur_mode;
2230 				ip->ino_data.ctime = trans.time;
2231 				modflags |= HAMMER_INODE_DDIRTY;
2232 			}
2233 			kflags |= NOTE_ATTRIB;
2234 		}
2235 	}
2236 	while (vap->va_size != VNOVAL && ip->ino_data.size != vap->va_size) {
2237 		switch(ap->a_vp->v_type) {
2238 		case VREG:
2239 			if (vap->va_size == ip->ino_data.size)
2240 				break;
2241 
2242 			/*
2243 			 * Log the operation if in fast-fsync mode or if
2244 			 * there are unterminated redo write records present.
2245 			 *
2246 			 * The second check is needed so the recovery code
2247 			 * properly truncates write redos even if nominal
2248 			 * REDO operations is turned off due to excessive
2249 			 * writes, because the related records might be
2250 			 * destroyed and never lay down a TERM_WRITE.
2251 			 */
2252 			if ((ip->flags & HAMMER_INODE_REDO) ||
2253 			    (ip->flags & HAMMER_INODE_RDIRTY)) {
2254 				error = hammer_generate_redo(&trans, ip,
2255 							     vap->va_size,
2256 							     HAMMER_REDO_TRUNC,
2257 							     NULL, 0);
2258 			}
2259 			blksize = hammer_blocksize(vap->va_size);
2260 
2261 			/*
2262 			 * XXX break atomicy, we can deadlock the backend
2263 			 * if we do not release the lock.  Probably not a
2264 			 * big deal here.
2265 			 */
2266 			if (vap->va_size < ip->ino_data.size) {
2267 				nvtruncbuf(ap->a_vp, vap->va_size,
2268 					   blksize,
2269 					   hammer_blockoff(vap->va_size),
2270 					   0);
2271 				truncating = 1;
2272 				kflags |= NOTE_WRITE;
2273 			} else {
2274 				nvextendbuf(ap->a_vp,
2275 					    ip->ino_data.size,
2276 					    vap->va_size,
2277 					    hammer_blocksize(ip->ino_data.size),
2278 					    hammer_blocksize(vap->va_size),
2279 					    hammer_blockoff(ip->ino_data.size),
2280 					    hammer_blockoff(vap->va_size),
2281 					    0);
2282 				truncating = 0;
2283 				kflags |= NOTE_WRITE | NOTE_EXTEND;
2284 			}
2285 			ip->ino_data.size = vap->va_size;
2286 			ip->ino_data.mtime = trans.time;
2287 			/* XXX safe to use SDIRTY instead of DDIRTY here? */
2288 			modflags |= HAMMER_INODE_MTIME | HAMMER_INODE_DDIRTY;
2289 
2290 			/*
2291 			 * On-media truncation is cached in the inode until
2292 			 * the inode is synchronized.  We must immediately
2293 			 * handle any frontend records.
2294 			 */
2295 			if (truncating) {
2296 				hammer_ip_frontend_trunc(ip, vap->va_size);
2297 				if ((ip->flags & HAMMER_INODE_TRUNCATED) == 0) {
2298 					ip->flags |= HAMMER_INODE_TRUNCATED;
2299 					ip->trunc_off = vap->va_size;
2300 					hammer_inode_dirty(ip);
2301 				} else if (ip->trunc_off > vap->va_size) {
2302 					ip->trunc_off = vap->va_size;
2303 				}
2304 			}
2305 
2306 #if 0
2307 			/*
2308 			 * When truncating, nvtruncbuf() may have cleaned out
2309 			 * a portion of the last block on-disk in the buffer
2310 			 * cache.  We must clean out any frontend records
2311 			 * for blocks beyond the new last block.
2312 			 */
2313 			aligned_size = (vap->va_size + (blksize - 1)) &
2314 				       ~(int64_t)(blksize - 1);
2315 			if (truncating && vap->va_size < aligned_size) {
2316 				aligned_size -= blksize;
2317 				hammer_ip_frontend_trunc(ip, aligned_size);
2318 			}
2319 #endif
2320 			break;
2321 		case VDATABASE:
2322 			if ((ip->flags & HAMMER_INODE_TRUNCATED) == 0) {
2323 				ip->flags |= HAMMER_INODE_TRUNCATED;
2324 				ip->trunc_off = vap->va_size;
2325 				hammer_inode_dirty(ip);
2326 			} else if (ip->trunc_off > vap->va_size) {
2327 				ip->trunc_off = vap->va_size;
2328 			}
2329 			hammer_ip_frontend_trunc(ip, vap->va_size);
2330 			ip->ino_data.size = vap->va_size;
2331 			ip->ino_data.mtime = trans.time;
2332 			modflags |= HAMMER_INODE_MTIME | HAMMER_INODE_DDIRTY;
2333 			kflags |= NOTE_ATTRIB;
2334 			break;
2335 		default:
2336 			error = EINVAL;
2337 			goto done;
2338 		}
2339 		break;
2340 	}
2341 	if (vap->va_atime.tv_sec != VNOVAL) {
2342 		ip->ino_data.atime = hammer_timespec_to_time(&vap->va_atime);
2343 		modflags |= HAMMER_INODE_ATIME;
2344 		kflags |= NOTE_ATTRIB;
2345 	}
2346 	if (vap->va_mtime.tv_sec != VNOVAL) {
2347 		ip->ino_data.mtime = hammer_timespec_to_time(&vap->va_mtime);
2348 		modflags |= HAMMER_INODE_MTIME;
2349 		kflags |= NOTE_ATTRIB;
2350 	}
2351 	if (vap->va_mode != (mode_t)VNOVAL) {
2352 		mode_t   cur_mode = ip->ino_data.mode;
2353 		uid_t cur_uid = hammer_to_unix_xid(&ip->ino_data.uid);
2354 		gid_t cur_gid = hammer_to_unix_xid(&ip->ino_data.gid);
2355 
2356 		error = vop_helper_chmod(ap->a_vp, vap->va_mode, ap->a_cred,
2357 					 cur_uid, cur_gid, &cur_mode);
2358 		if (error == 0 && ip->ino_data.mode != cur_mode) {
2359 			ip->ino_data.mode = cur_mode;
2360 			ip->ino_data.ctime = trans.time;
2361 			modflags |= HAMMER_INODE_DDIRTY;
2362 			kflags |= NOTE_ATTRIB;
2363 		}
2364 	}
2365 done:
2366 	if (error == 0)
2367 		hammer_modify_inode(&trans, ip, modflags);
2368 	hammer_done_transaction(&trans);
2369 	hammer_knote(ap->a_vp, kflags);
2370 	lwkt_reltoken(&hmp->fs_token);
2371 	return (error);
2372 }
2373 
2374 /*
2375  * hammer_vop_nsymlink { nch, dvp, vpp, cred, vap, target }
2376  */
2377 static
2378 int
2379 hammer_vop_nsymlink(struct vop_nsymlink_args *ap)
2380 {
2381 	struct hammer_transaction trans;
2382 	hammer_inode_t dip;
2383 	hammer_inode_t nip;
2384 	hammer_record_t record;
2385 	struct nchandle *nch;
2386 	hammer_mount_t hmp;
2387 	int error;
2388 	int bytes;
2389 
2390 	ap->a_vap->va_type = VLNK;
2391 
2392 	nch = ap->a_nch;
2393 	dip = VTOI(ap->a_dvp);
2394 	hmp = dip->hmp;
2395 
2396 	if (dip->flags & HAMMER_INODE_RO)
2397 		return (EROFS);
2398 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
2399 		return (error);
2400 
2401 	/*
2402 	 * Create a transaction to cover the operations we perform.
2403 	 */
2404 	lwkt_gettoken(&hmp->fs_token);
2405 	hammer_start_transaction(&trans, hmp);
2406 	++hammer_stats_file_iopsw;
2407 
2408 	/*
2409 	 * Create a new filesystem object of the requested type.  The
2410 	 * returned inode will be referenced but not locked.
2411 	 */
2412 
2413 	error = hammer_create_inode(&trans, ap->a_vap, ap->a_cred,
2414 				    dip, nch->ncp->nc_name, nch->ncp->nc_nlen,
2415 				    NULL, &nip);
2416 	if (error) {
2417 		hammer_done_transaction(&trans);
2418 		*ap->a_vpp = NULL;
2419 		lwkt_reltoken(&hmp->fs_token);
2420 		return (error);
2421 	}
2422 
2423 	/*
2424 	 * Add a record representing the symlink.  symlink stores the link
2425 	 * as pure data, not a string, and is no \0 terminated.
2426 	 */
2427 	if (error == 0) {
2428 		bytes = strlen(ap->a_target);
2429 
2430 		if (bytes <= HAMMER_INODE_BASESYMLEN) {
2431 			bcopy(ap->a_target, nip->ino_data.ext.symlink, bytes);
2432 		} else {
2433 			record = hammer_alloc_mem_record(nip, bytes);
2434 			record->type = HAMMER_MEM_RECORD_GENERAL;
2435 
2436 			record->leaf.base.localization = nip->obj_localization |
2437 							 HAMMER_LOCALIZE_MISC;
2438 			record->leaf.base.key = HAMMER_FIXKEY_SYMLINK;
2439 			record->leaf.base.rec_type = HAMMER_RECTYPE_FIX;
2440 			record->leaf.data_len = bytes;
2441 			KKASSERT(HAMMER_SYMLINK_NAME_OFF == 0);
2442 			bcopy(ap->a_target, record->data->symlink.name, bytes);
2443 			error = hammer_ip_add_record(&trans, record);
2444 		}
2445 
2446 		/*
2447 		 * Set the file size to the length of the link.
2448 		 */
2449 		if (error == 0) {
2450 			nip->ino_data.size = bytes;
2451 			hammer_modify_inode(&trans, nip, HAMMER_INODE_DDIRTY);
2452 		}
2453 	}
2454 	if (error == 0)
2455 		error = hammer_ip_add_direntry(&trans, dip, nch->ncp->nc_name,
2456 						nch->ncp->nc_nlen, nip);
2457 
2458 	/*
2459 	 * Finish up.
2460 	 */
2461 	if (error) {
2462 		hammer_rel_inode(nip, 0);
2463 		*ap->a_vpp = NULL;
2464 	} else {
2465 		error = hammer_get_vnode(nip, ap->a_vpp);
2466 		hammer_rel_inode(nip, 0);
2467 		if (error == 0) {
2468 			cache_setunresolved(ap->a_nch);
2469 			cache_setvp(ap->a_nch, *ap->a_vpp);
2470 			hammer_knote(ap->a_dvp, NOTE_WRITE);
2471 		}
2472 	}
2473 	hammer_done_transaction(&trans);
2474 	lwkt_reltoken(&hmp->fs_token);
2475 	return (error);
2476 }
2477 
2478 /*
2479  * hammer_vop_nwhiteout { nch, dvp, cred, flags }
2480  */
2481 static
2482 int
2483 hammer_vop_nwhiteout(struct vop_nwhiteout_args *ap)
2484 {
2485 	struct hammer_transaction trans;
2486 	hammer_inode_t dip;
2487 	hammer_mount_t hmp;
2488 	int error;
2489 
2490 	dip = VTOI(ap->a_dvp);
2491 	hmp = dip->hmp;
2492 
2493 	if (hammer_nohistory(dip) == 0 &&
2494 	    (error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0) {
2495 		return (error);
2496 	}
2497 
2498 	lwkt_gettoken(&hmp->fs_token);
2499 	hammer_start_transaction(&trans, hmp);
2500 	++hammer_stats_file_iopsw;
2501 	error = hammer_dounlink(&trans, ap->a_nch, ap->a_dvp,
2502 				ap->a_cred, ap->a_flags, -1);
2503 	hammer_done_transaction(&trans);
2504 	lwkt_reltoken(&hmp->fs_token);
2505 
2506 	return (error);
2507 }
2508 
2509 /*
2510  * hammer_vop_ioctl { vp, command, data, fflag, cred }
2511  */
2512 static
2513 int
2514 hammer_vop_ioctl(struct vop_ioctl_args *ap)
2515 {
2516 	hammer_inode_t ip = ap->a_vp->v_data;
2517 	hammer_mount_t hmp = ip->hmp;
2518 	int error;
2519 
2520 	++hammer_stats_file_iopsr;
2521 	lwkt_gettoken(&hmp->fs_token);
2522 	error = hammer_ioctl(ip, ap->a_command, ap->a_data,
2523 			     ap->a_fflag, ap->a_cred);
2524 	lwkt_reltoken(&hmp->fs_token);
2525 	return (error);
2526 }
2527 
2528 static
2529 int
2530 hammer_vop_mountctl(struct vop_mountctl_args *ap)
2531 {
2532 	static const struct mountctl_opt extraopt[] = {
2533 		{ HMNT_NOHISTORY,	"nohistory" },
2534 		{ HMNT_MASTERID,	"master" },
2535 		{ HMNT_NOMIRROR,	"nomirror" },
2536 		{ 0, NULL}
2537 
2538 	};
2539 	hammer_mount_t hmp;
2540 	struct mount *mp;
2541 	int usedbytes;
2542 	int error;
2543 
2544 	error = 0;
2545 	usedbytes = 0;
2546 	mp = ap->a_head.a_ops->head.vv_mount;
2547 	KKASSERT(mp->mnt_data != NULL);
2548 	hmp = (hammer_mount_t)mp->mnt_data;
2549 
2550 	lwkt_gettoken(&hmp->fs_token);
2551 
2552 	switch(ap->a_op) {
2553 	case MOUNTCTL_SET_EXPORT:
2554 		if (ap->a_ctllen != sizeof(struct export_args))
2555 			error = EINVAL;
2556 		else
2557 			error = hammer_vfs_export(mp, ap->a_op,
2558 				      (const struct export_args *)ap->a_ctl);
2559 		break;
2560 	case MOUNTCTL_MOUNTFLAGS:
2561 		/*
2562 		 * Call standard mountctl VOP function
2563 		 * so we get user mount flags.
2564 		 */
2565 		error = vop_stdmountctl(ap);
2566 		if (error)
2567 			break;
2568 
2569 		usedbytes = *ap->a_res;
2570 
2571 		if (usedbytes > 0 && usedbytes < ap->a_buflen) {
2572 			usedbytes += vfs_flagstostr(hmp->hflags, extraopt,
2573 						    ap->a_buf,
2574 						    ap->a_buflen - usedbytes,
2575 						    &error);
2576 		}
2577 
2578 		*ap->a_res += usedbytes;
2579 		break;
2580 	default:
2581 		error = vop_stdmountctl(ap);
2582 		break;
2583 	}
2584 	lwkt_reltoken(&hmp->fs_token);
2585 	return(error);
2586 }
2587 
2588 /*
2589  * hammer_vop_strategy { vp, bio }
2590  *
2591  * Strategy call, used for regular file read & write only.  Note that the
2592  * bp may represent a cluster.
2593  *
2594  * To simplify operation and allow better optimizations in the future,
2595  * this code does not make any assumptions with regards to buffer alignment
2596  * or size.
2597  */
2598 static
2599 int
2600 hammer_vop_strategy(struct vop_strategy_args *ap)
2601 {
2602 	struct buf *bp;
2603 	int error;
2604 
2605 	bp = ap->a_bio->bio_buf;
2606 
2607 	switch(bp->b_cmd) {
2608 	case BUF_CMD_READ:
2609 		error = hammer_vop_strategy_read(ap);
2610 		break;
2611 	case BUF_CMD_WRITE:
2612 		error = hammer_vop_strategy_write(ap);
2613 		break;
2614 	default:
2615 		bp->b_error = error = EINVAL;
2616 		bp->b_flags |= B_ERROR;
2617 		biodone(ap->a_bio);
2618 		break;
2619 	}
2620 
2621 	/* hammer_dump_dedup_cache(((hammer_inode_t)ap->a_vp->v_data)->hmp); */
2622 
2623 	return (error);
2624 }
2625 
2626 /*
2627  * Read from a regular file.  Iterate the related records and fill in the
2628  * BIO/BUF.  Gaps are zero-filled.
2629  *
2630  * The support code in hammer_object.c should be used to deal with mixed
2631  * in-memory and on-disk records.
2632  *
2633  * NOTE: Can be called from the cluster code with an oversized buf.
2634  *
2635  * XXX atime update
2636  */
2637 static
2638 int
2639 hammer_vop_strategy_read(struct vop_strategy_args *ap)
2640 {
2641 	struct hammer_transaction trans;
2642 	hammer_inode_t ip;
2643 	hammer_inode_t dip;
2644 	hammer_mount_t hmp;
2645 	struct hammer_cursor cursor;
2646 	hammer_base_elm_t base;
2647 	hammer_off_t disk_offset;
2648 	struct bio *bio;
2649 	struct bio *nbio;
2650 	struct buf *bp;
2651 	int64_t rec_offset;
2652 	int64_t ran_end;
2653 	int64_t tmp64;
2654 	int error;
2655 	int boff;
2656 	int roff;
2657 	int n;
2658 	int isdedupable;
2659 
2660 	bio = ap->a_bio;
2661 	bp = bio->bio_buf;
2662 	ip = ap->a_vp->v_data;
2663 	hmp = ip->hmp;
2664 
2665 	/*
2666 	 * The zone-2 disk offset may have been set by the cluster code via
2667 	 * a BMAP operation, or else should be NOOFFSET.
2668 	 *
2669 	 * Checking the high bits for a match against zone-2 should suffice.
2670 	 *
2671 	 * In cases where a lot of data duplication is present it may be
2672 	 * more beneficial to drop through and doubule-buffer through the
2673 	 * device.
2674 	 */
2675 	nbio = push_bio(bio);
2676 	if (hammer_is_zone_large_data(nbio->bio_offset)) {
2677 		if (hammer_double_buffer == 0) {
2678 			lwkt_gettoken(&hmp->fs_token);
2679 			error = hammer_io_direct_read(hmp, nbio, NULL);
2680 			lwkt_reltoken(&hmp->fs_token);
2681 			return (error);
2682 		}
2683 
2684 		/*
2685 		 * Try to shortcut requests for double_buffer mode too.
2686 		 * Since this mode runs through the device buffer cache
2687 		 * only compatible buffer sizes (meaning those generated
2688 		 * by normal filesystem buffers) are legal.
2689 		 */
2690 		if (hammer_live_dedup == 0 && (bp->b_flags & B_PAGING) == 0) {
2691 			lwkt_gettoken(&hmp->fs_token);
2692 			error = hammer_io_indirect_read(hmp, nbio, NULL);
2693 			lwkt_reltoken(&hmp->fs_token);
2694 			return (error);
2695 		}
2696 	}
2697 
2698 	/*
2699 	 * Well, that sucked.  Do it the hard way.  If all the stars are
2700 	 * aligned we may still be able to issue a direct-read.
2701 	 */
2702 	lwkt_gettoken(&hmp->fs_token);
2703 	hammer_simple_transaction(&trans, hmp);
2704 	hammer_init_cursor(&trans, &cursor, &ip->cache[1], ip);
2705 
2706 	/*
2707 	 * Key range (begin and end inclusive) to scan.  Note that the key's
2708 	 * stored in the actual records represent BASE+LEN, not BASE.  The
2709 	 * first record containing bio_offset will have a key > bio_offset.
2710 	 */
2711 	cursor.key_beg.localization = ip->obj_localization |
2712 				      HAMMER_LOCALIZE_MISC;
2713 	cursor.key_beg.obj_id = ip->obj_id;
2714 	cursor.key_beg.create_tid = 0;
2715 	cursor.key_beg.delete_tid = 0;
2716 	cursor.key_beg.obj_type = 0;
2717 	cursor.key_beg.key = bio->bio_offset + 1;
2718 	cursor.asof = ip->obj_asof;
2719 	cursor.flags |= HAMMER_CURSOR_ASOF;
2720 
2721 	cursor.key_end = cursor.key_beg;
2722 	KKASSERT(ip->ino_data.obj_type == HAMMER_OBJTYPE_REGFILE);
2723 #if 0
2724 	if (ip->ino_data.obj_type == HAMMER_OBJTYPE_DBFILE) {
2725 		cursor.key_beg.rec_type = HAMMER_RECTYPE_DB;
2726 		cursor.key_end.rec_type = HAMMER_RECTYPE_DB;
2727 		cursor.key_end.key = 0x7FFFFFFFFFFFFFFFLL;
2728 	} else
2729 #endif
2730 	{
2731 		ran_end = bio->bio_offset + bp->b_bufsize;
2732 		cursor.key_beg.rec_type = HAMMER_RECTYPE_DATA;
2733 		cursor.key_end.rec_type = HAMMER_RECTYPE_DATA;
2734 		tmp64 = ran_end + MAXPHYS + 1;	/* work-around GCC-4 bug */
2735 		if (tmp64 < ran_end)
2736 			cursor.key_end.key = 0x7FFFFFFFFFFFFFFFLL;
2737 		else
2738 			cursor.key_end.key = ran_end + MAXPHYS + 1;
2739 	}
2740 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE;
2741 
2742 	/*
2743 	 * Set NOSWAPCACHE for cursor data extraction if double buffering
2744 	 * is disabled or (if the file is not marked cacheable via chflags
2745 	 * and vm.swapcache_use_chflags is enabled).
2746 	 */
2747 	if (hammer_double_buffer == 0 ||
2748 	    ((ap->a_vp->v_flag & VSWAPCACHE) == 0 &&
2749 	     vm_swapcache_use_chflags)) {
2750 		cursor.flags |= HAMMER_CURSOR_NOSWAPCACHE;
2751 	}
2752 
2753 	error = hammer_ip_first(&cursor);
2754 	boff = 0;
2755 
2756 	while (error == 0) {
2757 		/*
2758 		 * Get the base file offset of the record.  The key for
2759 		 * data records is (base + bytes) rather then (base).
2760 		 */
2761 		base = &cursor.leaf->base;
2762 		rec_offset = base->key - cursor.leaf->data_len;
2763 
2764 		/*
2765 		 * Calculate the gap, if any, and zero-fill it.
2766 		 *
2767 		 * n is the offset of the start of the record verses our
2768 		 * current seek offset in the bio.
2769 		 */
2770 		n = (int)(rec_offset - (bio->bio_offset + boff));
2771 		if (n > 0) {
2772 			if (n > bp->b_bufsize - boff)
2773 				n = bp->b_bufsize - boff;
2774 			bzero((char *)bp->b_data + boff, n);
2775 			boff += n;
2776 			n = 0;
2777 		}
2778 
2779 		/*
2780 		 * Calculate the data offset in the record and the number
2781 		 * of bytes we can copy.
2782 		 *
2783 		 * There are two degenerate cases.  First, boff may already
2784 		 * be at bp->b_bufsize.  Secondly, the data offset within
2785 		 * the record may exceed the record's size.
2786 		 */
2787 		roff = -n;
2788 		rec_offset += roff;
2789 		n = cursor.leaf->data_len - roff;
2790 		if (n <= 0) {
2791 			hdkprintf("bad n=%d roff=%d\n", n, roff);
2792 			n = 0;
2793 		} else if (n > bp->b_bufsize - boff) {
2794 			n = bp->b_bufsize - boff;
2795 		}
2796 
2797 		/*
2798 		 * Deal with cached truncations.  This cool bit of code
2799 		 * allows truncate()/ftruncate() to avoid having to sync
2800 		 * the file.
2801 		 *
2802 		 * If the frontend is truncated then all backend records are
2803 		 * subject to the frontend's truncation.
2804 		 *
2805 		 * If the backend is truncated then backend records on-disk
2806 		 * (but not in-memory) are subject to the backend's
2807 		 * truncation.  In-memory records owned by the backend
2808 		 * represent data written after the truncation point on the
2809 		 * backend and must not be truncated.
2810 		 *
2811 		 * Truncate operations deal with frontend buffer cache
2812 		 * buffers and frontend-owned in-memory records synchronously.
2813 		 */
2814 		if (ip->flags & HAMMER_INODE_TRUNCATED) {
2815 			if (hammer_cursor_ondisk(&cursor)/* ||
2816 			    cursor.iprec->flush_state == HAMMER_FST_FLUSH*/) {
2817 				if (ip->trunc_off <= rec_offset)
2818 					n = 0;
2819 				else if (ip->trunc_off < rec_offset + n)
2820 					n = (int)(ip->trunc_off - rec_offset);
2821 			}
2822 		}
2823 		if (ip->sync_flags & HAMMER_INODE_TRUNCATED) {
2824 			if (hammer_cursor_ondisk(&cursor)) {
2825 				if (ip->sync_trunc_off <= rec_offset)
2826 					n = 0;
2827 				else if (ip->sync_trunc_off < rec_offset + n)
2828 					n = (int)(ip->sync_trunc_off - rec_offset);
2829 			}
2830 		}
2831 
2832 		/*
2833 		 * Try to issue a direct read into our bio if possible,
2834 		 * otherwise resolve the element data into a hammer_buffer
2835 		 * and copy.
2836 		 *
2837 		 * The buffer on-disk should be zerod past any real
2838 		 * truncation point, but may not be for any synthesized
2839 		 * truncation point from above.
2840 		 *
2841 		 * NOTE: disk_offset is only valid if the cursor data is
2842 		 *	 on-disk.
2843 		 */
2844 		disk_offset = cursor.leaf->data_offset + roff;
2845 		isdedupable = (boff == 0 && n == bp->b_bufsize &&
2846 			       hammer_cursor_ondisk(&cursor) &&
2847 			       ((int)disk_offset & HAMMER_BUFMASK) == 0);
2848 
2849 		if (isdedupable && hammer_double_buffer == 0) {
2850 			/*
2851 			 * Direct read case
2852 			 */
2853 			KKASSERT(hammer_is_zone_large_data(disk_offset));
2854 			nbio->bio_offset = disk_offset;
2855 			error = hammer_io_direct_read(hmp, nbio, cursor.leaf);
2856 			if (hammer_live_dedup && error == 0)
2857 				hammer_dedup_cache_add(ip, cursor.leaf);
2858 			goto done;
2859 		} else if (isdedupable) {
2860 			/*
2861 			 * Async I/O case for reading from backing store
2862 			 * and copying the data to the filesystem buffer.
2863 			 * live-dedup has to verify the data anyway if it
2864 			 * gets a hit later so we can just add the entry
2865 			 * now.
2866 			 */
2867 			KKASSERT(hammer_is_zone_large_data(disk_offset));
2868 			nbio->bio_offset = disk_offset;
2869 			if (hammer_live_dedup)
2870 				hammer_dedup_cache_add(ip, cursor.leaf);
2871 			error = hammer_io_indirect_read(hmp, nbio, cursor.leaf);
2872 			goto done;
2873 		} else if (n) {
2874 			error = hammer_ip_resolve_data(&cursor);
2875 			if (error == 0) {
2876 				if (hammer_live_dedup && isdedupable)
2877 					hammer_dedup_cache_add(ip, cursor.leaf);
2878 				bcopy((char *)cursor.data + roff,
2879 				      (char *)bp->b_data + boff, n);
2880 			}
2881 		}
2882 		if (error)
2883 			break;
2884 
2885 		/*
2886 		 * We have to be sure that the only elements added to the
2887 		 * dedup cache are those which are already on-media.
2888 		 */
2889 		if (hammer_live_dedup && hammer_cursor_ondisk(&cursor))
2890 			hammer_dedup_cache_add(ip, cursor.leaf);
2891 
2892 		/*
2893 		 * Iterate until we have filled the request.
2894 		 */
2895 		boff += n;
2896 		if (boff == bp->b_bufsize)
2897 			break;
2898 		error = hammer_ip_next(&cursor);
2899 	}
2900 
2901 	/*
2902 	 * There may have been a gap after the last record
2903 	 */
2904 	if (error == ENOENT)
2905 		error = 0;
2906 	if (error == 0 && boff != bp->b_bufsize) {
2907 		KKASSERT(boff < bp->b_bufsize);
2908 		bzero((char *)bp->b_data + boff, bp->b_bufsize - boff);
2909 		/* boff = bp->b_bufsize; */
2910 	}
2911 
2912 	/*
2913 	 * Disallow swapcache operation on the vnode buffer if double
2914 	 * buffering is enabled, the swapcache will get the data via
2915 	 * the block device buffer.
2916 	 */
2917 	if (hammer_double_buffer)
2918 		bp->b_flags |= B_NOTMETA;
2919 
2920 	/*
2921 	 * Cleanup
2922 	 */
2923 	bp->b_resid = 0;
2924 	bp->b_error = error;
2925 	if (error)
2926 		bp->b_flags |= B_ERROR;
2927 	biodone(ap->a_bio);
2928 
2929 done:
2930 	/*
2931 	 * Cache the b-tree node for the last data read in cache[1].
2932 	 *
2933 	 * If we hit the file EOF then also cache the node in the
2934 	 * governing directory's cache[3], it will be used to initialize
2935 	 * the new inode's cache[1] for any inodes looked up via the directory.
2936 	 *
2937 	 * This doesn't reduce disk accesses since the B-Tree chain is
2938 	 * likely cached, but it does reduce cpu overhead when looking
2939 	 * up file offsets for cpdup/tar/cpio style iterations.
2940 	 */
2941 	if (cursor.node)
2942 		hammer_cache_node(&ip->cache[1], cursor.node);
2943 	if (ran_end >= ip->ino_data.size) {
2944 		dip = hammer_find_inode(&trans, ip->ino_data.parent_obj_id,
2945 					ip->obj_asof, ip->obj_localization);
2946 		if (dip) {
2947 			hammer_cache_node(&dip->cache[3], cursor.node);
2948 			hammer_rel_inode(dip, 0);
2949 		}
2950 	}
2951 	hammer_done_cursor(&cursor);
2952 	hammer_done_transaction(&trans);
2953 	lwkt_reltoken(&hmp->fs_token);
2954 	return(error);
2955 }
2956 
2957 /*
2958  * BMAP operation - used to support cluster_read() only.
2959  *
2960  * (struct vnode *vp, off_t loffset, off_t *doffsetp, int *runp, int *runb)
2961  *
2962  * This routine may return EOPNOTSUPP if the opration is not supported for
2963  * the specified offset.  The contents of the pointer arguments do not
2964  * need to be initialized in that case.
2965  *
2966  * If a disk address is available and properly aligned return 0 with
2967  * *doffsetp set to the zone-2 address, and *runp / *runb set appropriately
2968  * to the run-length relative to that offset.  Callers may assume that
2969  * *doffsetp is valid if 0 is returned, even if *runp is not sufficiently
2970  * large, so return EOPNOTSUPP if it is not sufficiently large.
2971  */
2972 static
2973 int
2974 hammer_vop_bmap(struct vop_bmap_args *ap)
2975 {
2976 	struct hammer_transaction trans;
2977 	hammer_inode_t ip;
2978 	hammer_mount_t hmp;
2979 	struct hammer_cursor cursor;
2980 	hammer_base_elm_t base;
2981 	int64_t rec_offset;
2982 	int64_t ran_end;
2983 	int64_t tmp64;
2984 	int64_t base_offset;
2985 	int64_t base_disk_offset;
2986 	int64_t last_offset;
2987 	hammer_off_t last_disk_offset;
2988 	hammer_off_t disk_offset;
2989 	int	rec_len;
2990 	int	error;
2991 	int	blksize;
2992 
2993 	++hammer_stats_file_iopsr;
2994 	ip = ap->a_vp->v_data;
2995 	hmp = ip->hmp;
2996 
2997 	/*
2998 	 * We can only BMAP regular files.  We can't BMAP database files,
2999 	 * directories, etc.
3000 	 */
3001 	if (ip->ino_data.obj_type != HAMMER_OBJTYPE_REGFILE)
3002 		return(EOPNOTSUPP);
3003 
3004 	/*
3005 	 * bmap is typically called with runp/runb both NULL when used
3006 	 * for writing.  We do not support BMAP for writing atm.
3007 	 */
3008 	if (ap->a_cmd != BUF_CMD_READ)
3009 		return(EOPNOTSUPP);
3010 
3011 	/*
3012 	 * Scan the B-Tree to acquire blockmap addresses, then translate
3013 	 * to raw addresses.
3014 	 */
3015 	lwkt_gettoken(&hmp->fs_token);
3016 	hammer_simple_transaction(&trans, hmp);
3017 
3018 	hammer_init_cursor(&trans, &cursor, &ip->cache[1], ip);
3019 
3020 	/*
3021 	 * Key range (begin and end inclusive) to scan.  Note that the key's
3022 	 * stored in the actual records represent BASE+LEN, not BASE.  The
3023 	 * first record containing bio_offset will have a key > bio_offset.
3024 	 */
3025 	cursor.key_beg.localization = ip->obj_localization |
3026 				      HAMMER_LOCALIZE_MISC;
3027 	cursor.key_beg.obj_id = ip->obj_id;
3028 	cursor.key_beg.create_tid = 0;
3029 	cursor.key_beg.delete_tid = 0;
3030 	cursor.key_beg.obj_type = 0;
3031 	if (ap->a_runb)
3032 		cursor.key_beg.key = ap->a_loffset - MAXPHYS + 1;
3033 	else
3034 		cursor.key_beg.key = ap->a_loffset + 1;
3035 	if (cursor.key_beg.key < 0)
3036 		cursor.key_beg.key = 0;
3037 	cursor.asof = ip->obj_asof;
3038 	cursor.flags |= HAMMER_CURSOR_ASOF;
3039 
3040 	cursor.key_end = cursor.key_beg;
3041 	KKASSERT(ip->ino_data.obj_type == HAMMER_OBJTYPE_REGFILE);
3042 
3043 	ran_end = ap->a_loffset + MAXPHYS;
3044 	cursor.key_beg.rec_type = HAMMER_RECTYPE_DATA;
3045 	cursor.key_end.rec_type = HAMMER_RECTYPE_DATA;
3046 	tmp64 = ran_end + MAXPHYS + 1;	/* work-around GCC-4 bug */
3047 	if (tmp64 < ran_end)
3048 		cursor.key_end.key = 0x7FFFFFFFFFFFFFFFLL;
3049 	else
3050 		cursor.key_end.key = ran_end + MAXPHYS + 1;
3051 
3052 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE;
3053 
3054 	error = hammer_ip_first(&cursor);
3055 	base_offset = last_offset = 0;
3056 	base_disk_offset = last_disk_offset = 0;
3057 
3058 	while (error == 0) {
3059 		/*
3060 		 * Get the base file offset of the record.  The key for
3061 		 * data records is (base + bytes) rather then (base).
3062 		 *
3063 		 * NOTE: rec_offset + rec_len may exceed the end-of-file.
3064 		 * The extra bytes should be zero on-disk and the BMAP op
3065 		 * should still be ok.
3066 		 */
3067 		base = &cursor.leaf->base;
3068 		rec_offset = base->key - cursor.leaf->data_len;
3069 		rec_len    = cursor.leaf->data_len;
3070 
3071 		/*
3072 		 * Incorporate any cached truncation.
3073 		 *
3074 		 * NOTE: Modifications to rec_len based on synthesized
3075 		 * truncation points remove the guarantee that any extended
3076 		 * data on disk is zero (since the truncations may not have
3077 		 * taken place on-media yet).
3078 		 */
3079 		if (ip->flags & HAMMER_INODE_TRUNCATED) {
3080 			if (hammer_cursor_ondisk(&cursor) ||
3081 			    cursor.iprec->flush_state == HAMMER_FST_FLUSH) {
3082 				if (ip->trunc_off <= rec_offset)
3083 					rec_len = 0;
3084 				else if (ip->trunc_off < rec_offset + rec_len)
3085 					rec_len = (int)(ip->trunc_off - rec_offset);
3086 			}
3087 		}
3088 		if (ip->sync_flags & HAMMER_INODE_TRUNCATED) {
3089 			if (hammer_cursor_ondisk(&cursor)) {
3090 				if (ip->sync_trunc_off <= rec_offset)
3091 					rec_len = 0;
3092 				else if (ip->sync_trunc_off < rec_offset + rec_len)
3093 					rec_len = (int)(ip->sync_trunc_off - rec_offset);
3094 			}
3095 		}
3096 
3097 		/*
3098 		 * Accumulate information.  If we have hit a discontiguous
3099 		 * block reset base_offset unless we are already beyond the
3100 		 * requested offset.  If we are, that's it, we stop.
3101 		 */
3102 		if (error)
3103 			break;
3104 		if (hammer_cursor_ondisk(&cursor)) {
3105 			disk_offset = cursor.leaf->data_offset;
3106 			if (rec_offset != last_offset ||
3107 			    disk_offset != last_disk_offset) {
3108 				if (rec_offset > ap->a_loffset)
3109 					break;
3110 				base_offset = rec_offset;
3111 				base_disk_offset = disk_offset;
3112 			}
3113 			last_offset = rec_offset + rec_len;
3114 			last_disk_offset = disk_offset + rec_len;
3115 
3116 			if (hammer_live_dedup)
3117 				hammer_dedup_cache_add(ip, cursor.leaf);
3118 		}
3119 
3120 		error = hammer_ip_next(&cursor);
3121 	}
3122 
3123 	if (cursor.node)
3124 		hammer_cache_node(&ip->cache[1], cursor.node);
3125 
3126 	hammer_done_cursor(&cursor);
3127 	hammer_done_transaction(&trans);
3128 	lwkt_reltoken(&hmp->fs_token);
3129 
3130 	/*
3131 	 * If we couldn't find any records or the records we did find were
3132 	 * all behind the requested offset, return failure.  A forward
3133 	 * truncation can leave a hole w/ no on-disk records.
3134 	 */
3135 	if (last_offset == 0 || last_offset < ap->a_loffset)
3136 		return (EOPNOTSUPP);
3137 
3138 	/*
3139 	 * Figure out the block size at the requested offset and adjust
3140 	 * our limits so the cluster_read() does not create inappropriately
3141 	 * sized buffer cache buffers.
3142 	 */
3143 	blksize = hammer_blocksize(ap->a_loffset);
3144 	if (hammer_blocksize(base_offset) != blksize) {
3145 		base_offset = hammer_blockdemarc(base_offset, ap->a_loffset);
3146 	}
3147 	if (last_offset != ap->a_loffset &&
3148 	    hammer_blocksize(last_offset - 1) != blksize) {
3149 		last_offset = hammer_blockdemarc(ap->a_loffset,
3150 						 last_offset - 1);
3151 	}
3152 
3153 	/*
3154 	 * Returning EOPNOTSUPP simply prevents the direct-IO optimization
3155 	 * from occuring.
3156 	 */
3157 	disk_offset = base_disk_offset + (ap->a_loffset - base_offset);
3158 
3159 	if (!hammer_is_zone_large_data(disk_offset)) {
3160 		/*
3161 		 * Only large-data zones can be direct-IOd
3162 		 */
3163 		error = EOPNOTSUPP;
3164 	} else if ((disk_offset & HAMMER_BUFMASK) ||
3165 		   (last_offset - ap->a_loffset) < blksize) {
3166 		/*
3167 		 * doffsetp is not aligned or the forward run size does
3168 		 * not cover a whole buffer, disallow the direct I/O.
3169 		 */
3170 		error = EOPNOTSUPP;
3171 	} else {
3172 		/*
3173 		 * We're good.
3174 		 */
3175 		*ap->a_doffsetp = disk_offset;
3176 		if (ap->a_runb) {
3177 			*ap->a_runb = ap->a_loffset - base_offset;
3178 			KKASSERT(*ap->a_runb >= 0);
3179 		}
3180 		if (ap->a_runp) {
3181 			*ap->a_runp = last_offset - ap->a_loffset;
3182 			KKASSERT(*ap->a_runp >= 0);
3183 		}
3184 		error = 0;
3185 	}
3186 	return(error);
3187 }
3188 
3189 /*
3190  * Write to a regular file.   Because this is a strategy call the OS is
3191  * trying to actually get data onto the media.
3192  */
3193 static
3194 int
3195 hammer_vop_strategy_write(struct vop_strategy_args *ap)
3196 {
3197 	hammer_record_t record;
3198 	hammer_mount_t hmp;
3199 	hammer_inode_t ip;
3200 	struct bio *bio;
3201 	struct buf *bp;
3202 	int blksize __debugvar;
3203 	int bytes;
3204 	int error;
3205 
3206 	bio = ap->a_bio;
3207 	bp = bio->bio_buf;
3208 	ip = ap->a_vp->v_data;
3209 	hmp = ip->hmp;
3210 
3211 	blksize = hammer_blocksize(bio->bio_offset);
3212 	KKASSERT(bp->b_bufsize == blksize);
3213 
3214 	if (ip->flags & HAMMER_INODE_RO) {
3215 		bp->b_error = EROFS;
3216 		bp->b_flags |= B_ERROR;
3217 		biodone(ap->a_bio);
3218 		return(EROFS);
3219 	}
3220 
3221 	lwkt_gettoken(&hmp->fs_token);
3222 
3223 	/*
3224 	 * Disallow swapcache operation on the vnode buffer if double
3225 	 * buffering is enabled, the swapcache will get the data via
3226 	 * the block device buffer.
3227 	 */
3228 	if (hammer_double_buffer)
3229 		bp->b_flags |= B_NOTMETA;
3230 
3231 	/*
3232 	 * Interlock with inode destruction (no in-kernel or directory
3233 	 * topology visibility).  If we queue new IO while trying to
3234 	 * destroy the inode we can deadlock the vtrunc call in
3235 	 * hammer_inode_unloadable_check().
3236 	 *
3237 	 * Besides, there's no point flushing a bp associated with an
3238 	 * inode that is being destroyed on-media and has no kernel
3239 	 * references.
3240 	 */
3241 	if ((ip->flags | ip->sync_flags) &
3242 	    (HAMMER_INODE_DELETING|HAMMER_INODE_DELETED)) {
3243 		bp->b_resid = 0;
3244 		biodone(ap->a_bio);
3245 		lwkt_reltoken(&hmp->fs_token);
3246 		return(0);
3247 	}
3248 
3249 	/*
3250 	 * Reserve space and issue a direct-write from the front-end.
3251 	 * NOTE: The direct_io code will hammer_bread/bcopy smaller
3252 	 * allocations.
3253 	 *
3254 	 * An in-memory record will be installed to reference the storage
3255 	 * until the flusher can get to it.
3256 	 *
3257 	 * Since we own the high level bio the front-end will not try to
3258 	 * do a direct-read until the write completes.
3259 	 *
3260 	 * NOTE: The only time we do not reserve a full-sized buffers
3261 	 * worth of data is if the file is small.  We do not try to
3262 	 * allocate a fragment (from the small-data zone) at the end of
3263 	 * an otherwise large file as this can lead to wildly separated
3264 	 * data.
3265 	 */
3266 	KKASSERT((bio->bio_offset & HAMMER_BUFMASK) == 0);
3267 	KKASSERT(bio->bio_offset < ip->ino_data.size);
3268 	if (bio->bio_offset || ip->ino_data.size > HAMMER_HBUFSIZE)
3269 		bytes = bp->b_bufsize;
3270 	else
3271 		bytes = ((int)ip->ino_data.size + 15) & ~15;
3272 
3273 	record = hammer_ip_add_bulk(ip, bio->bio_offset, bp->b_data,
3274 				    bytes, &error);
3275 
3276 	/*
3277 	 * B_VFSFLAG1 indicates that a REDO_WRITE entry was generated
3278 	 * in hammer_vop_write().  We must flag the record so the proper
3279 	 * REDO_TERM_WRITE entry is generated during the flush.
3280 	 */
3281 	if (record) {
3282 		if (bp->b_flags & B_VFSFLAG1) {
3283 			record->flags |= HAMMER_RECF_REDO;
3284 			bp->b_flags &= ~B_VFSFLAG1;
3285 		}
3286 		if (record->flags & HAMMER_RECF_DEDUPED) {
3287 			bp->b_resid = 0;
3288 			hammer_ip_replace_bulk(hmp, record);
3289 			biodone(ap->a_bio);
3290 		} else {
3291 			hammer_io_direct_write(hmp, bio, record);
3292 		}
3293 		if (ip->rsv_recs > 1 && hmp->rsv_recs > hammer_limit_recs)
3294 			hammer_flush_inode(ip, 0);
3295 	} else {
3296 		bp->b_bio2.bio_offset = NOOFFSET;
3297 		bp->b_error = error;
3298 		bp->b_flags |= B_ERROR;
3299 		biodone(ap->a_bio);
3300 	}
3301 	lwkt_reltoken(&hmp->fs_token);
3302 	return(error);
3303 }
3304 
3305 /*
3306  * dounlink - disconnect a directory entry
3307  *
3308  * XXX whiteout support not really in yet
3309  */
3310 static int
3311 hammer_dounlink(hammer_transaction_t trans, struct nchandle *nch,
3312 		struct vnode *dvp, struct ucred *cred,
3313 		int flags, int isdir)
3314 {
3315 	struct namecache *ncp;
3316 	hammer_inode_t dip;
3317 	hammer_inode_t ip;
3318 	hammer_mount_t hmp;
3319 	struct hammer_cursor cursor;
3320 	int64_t namekey;
3321 	uint32_t max_iterations;
3322 	int nlen, error;
3323 
3324 	/*
3325 	 * Calculate the namekey and setup the key range for the scan.  This
3326 	 * works kinda like a chained hash table where the lower 32 bits
3327 	 * of the namekey synthesize the chain.
3328 	 *
3329 	 * The key range is inclusive of both key_beg and key_end.
3330 	 */
3331 	dip = VTOI(dvp);
3332 	ncp = nch->ncp;
3333 	hmp = dip->hmp;
3334 
3335 	if (dip->flags & HAMMER_INODE_RO)
3336 		return (EROFS);
3337 
3338 	namekey = hammer_direntry_namekey(dip, ncp->nc_name, ncp->nc_nlen,
3339 					   &max_iterations);
3340 retry:
3341 	hammer_init_cursor(trans, &cursor, &dip->cache[1], dip);
3342 	cursor.key_beg.localization = dip->obj_localization |
3343 				      hammer_dir_localization(dip);
3344         cursor.key_beg.obj_id = dip->obj_id;
3345 	cursor.key_beg.key = namekey;
3346         cursor.key_beg.create_tid = 0;
3347         cursor.key_beg.delete_tid = 0;
3348         cursor.key_beg.rec_type = HAMMER_RECTYPE_DIRENTRY;
3349         cursor.key_beg.obj_type = 0;
3350 
3351 	cursor.key_end = cursor.key_beg;
3352 	cursor.key_end.key += max_iterations;
3353 	cursor.asof = dip->obj_asof;
3354 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF;
3355 
3356 	/*
3357 	 * Scan all matching records (the chain), locate the one matching
3358 	 * the requested path component.  info->last_error contains the
3359 	 * error code on search termination and could be 0, ENOENT, or
3360 	 * something else.
3361 	 *
3362 	 * The hammer_ip_*() functions merge in-memory records with on-disk
3363 	 * records for the purposes of the search.
3364 	 */
3365 	error = hammer_ip_first(&cursor);
3366 
3367 	while (error == 0) {
3368 		error = hammer_ip_resolve_data(&cursor);
3369 		if (error)
3370 			break;
3371 		nlen = cursor.leaf->data_len - HAMMER_ENTRY_NAME_OFF;
3372 		KKASSERT(nlen > 0);
3373 		if (ncp->nc_nlen == nlen &&
3374 		    bcmp(ncp->nc_name, cursor.data->entry.name, nlen) == 0) {
3375 			break;
3376 		}
3377 		error = hammer_ip_next(&cursor);
3378 	}
3379 
3380 	/*
3381 	 * If all is ok we have to get the inode so we can adjust nlinks.
3382 	 * To avoid a deadlock with the flusher we must release the inode
3383 	 * lock on the directory when acquiring the inode for the entry.
3384 	 *
3385 	 * If the target is a directory, it must be empty.
3386 	 */
3387 	if (error == 0) {
3388 		hammer_unlock(&cursor.ip->lock);
3389 		ip = hammer_get_inode(trans, dip, cursor.data->entry.obj_id,
3390 				      hmp->asof,
3391 				      cursor.data->entry.localization,
3392 				      0, &error);
3393 		hammer_lock_sh(&cursor.ip->lock);
3394 		if (error == ENOENT) {
3395 			hkprintf("WARNING: Removing dirent w/missing inode "
3396 				"\"%s\"\n"
3397 				"\tobj_id = %016jx\n",
3398 				ncp->nc_name,
3399 				(intmax_t)cursor.data->entry.obj_id);
3400 			error = 0;
3401 		}
3402 
3403 		/*
3404 		 * If isdir >= 0 we validate that the entry is or is not a
3405 		 * directory.  If isdir < 0 we don't care.
3406 		 */
3407 		if (error == 0 && isdir >= 0 && ip) {
3408 			if (isdir &&
3409 			    ip->ino_data.obj_type != HAMMER_OBJTYPE_DIRECTORY) {
3410 				error = ENOTDIR;
3411 			} else if (isdir == 0 &&
3412 			    ip->ino_data.obj_type == HAMMER_OBJTYPE_DIRECTORY) {
3413 				error = EISDIR;
3414 			}
3415 		}
3416 
3417 		/*
3418 		 * If we are trying to remove a directory the directory must
3419 		 * be empty.
3420 		 *
3421 		 * The check directory code can loop and deadlock/retry.  Our
3422 		 * own cursor's node locks must be released to avoid a 3-way
3423 		 * deadlock with the flusher if the check directory code
3424 		 * blocks.
3425 		 *
3426 		 * If any changes whatsoever have been made to the cursor
3427 		 * set EDEADLK and retry.
3428 		 *
3429 		 * WARNING: See warnings in hammer_unlock_cursor()
3430 		 *	    function.
3431 		 */
3432 		if (error == 0 && ip && ip->ino_data.obj_type ==
3433 				        HAMMER_OBJTYPE_DIRECTORY) {
3434 			hammer_unlock_cursor(&cursor);
3435 			error = hammer_ip_check_directory_empty(trans, ip);
3436 			hammer_lock_cursor(&cursor);
3437 			if (cursor.flags & HAMMER_CURSOR_RETEST) {
3438 				hkprintf("Warning: avoided deadlock "
3439 					"on rmdir '%s'\n",
3440 					ncp->nc_name);
3441 				error = EDEADLK;
3442 			}
3443 		}
3444 
3445 		/*
3446 		 * Delete the directory entry.
3447 		 *
3448 		 * WARNING: hammer_ip_del_direntry() may have to terminate
3449 		 * the cursor to avoid a deadlock.  It is ok to call
3450 		 * hammer_done_cursor() twice.
3451 		 */
3452 		if (error == 0) {
3453 			error = hammer_ip_del_direntry(trans, &cursor,
3454 							dip, ip);
3455 		}
3456 		hammer_done_cursor(&cursor);
3457 		if (error == 0) {
3458 			/*
3459 			 * Tell the namecache that we are now unlinked.
3460 			 */
3461 			cache_unlink(nch);
3462 
3463 			/*
3464 			 * NOTE: ip->vp, if non-NULL, cannot be directly
3465 			 *	 referenced without formally acquiring the
3466 			 *	 vp since the vp might have zero refs on it,
3467 			 *	 or in the middle of a reclaim, etc.
3468 			 *
3469 			 * NOTE: The cache_setunresolved() can rip the vp
3470 			 *	 out from under us since the vp may not have
3471 			 *	 any refs, in which case ip->vp will be NULL
3472 			 *	 from the outset.
3473 			 */
3474 			while (ip && ip->vp) {
3475 				struct vnode *vp;
3476 
3477 				error = hammer_get_vnode(ip, &vp);
3478 				if (error == 0 && vp) {
3479 					vn_unlock(vp);
3480 					hammer_knote(ip->vp, NOTE_DELETE);
3481 #if 0
3482 					/*
3483 					 * Don't do this, it can deadlock
3484 					 * on concurrent rm's of hardlinks.
3485 					 * Shouldn't be needed any more.
3486 					 */
3487 					cache_inval_vp(ip->vp, CINV_DESTROY);
3488 #endif
3489 					vrele(vp);
3490 					break;
3491 				}
3492 				hdkprintf("ip/vp race1 avoided\n");
3493 			}
3494 		}
3495 		if (ip)
3496 			hammer_rel_inode(ip, 0);
3497 	} else {
3498 		hammer_done_cursor(&cursor);
3499 	}
3500 	if (error == EDEADLK)
3501 		goto retry;
3502 
3503 	return (error);
3504 }
3505 
3506 /************************************************************************
3507  *			    FIFO AND SPECFS OPS				*
3508  ************************************************************************
3509  *
3510  */
3511 static int
3512 hammer_vop_fifoclose (struct vop_close_args *ap)
3513 {
3514 	/* XXX update itimes */
3515 	return (VOCALL(&fifo_vnode_vops, &ap->a_head));
3516 }
3517 
3518 static int
3519 hammer_vop_fiforead (struct vop_read_args *ap)
3520 {
3521 	int error;
3522 
3523 	error = VOCALL(&fifo_vnode_vops, &ap->a_head);
3524 	/* XXX update access time */
3525 	return (error);
3526 }
3527 
3528 static int
3529 hammer_vop_fifowrite (struct vop_write_args *ap)
3530 {
3531 	int error;
3532 
3533 	error = VOCALL(&fifo_vnode_vops, &ap->a_head);
3534 	/* XXX update access time */
3535 	return (error);
3536 }
3537 
3538 static
3539 int
3540 hammer_vop_fifokqfilter(struct vop_kqfilter_args *ap)
3541 {
3542 	int error;
3543 
3544 	error = VOCALL(&fifo_vnode_vops, &ap->a_head);
3545 	if (error)
3546 		error = hammer_vop_kqfilter(ap);
3547 	return(error);
3548 }
3549 
3550 /************************************************************************
3551  *			    KQFILTER OPS				*
3552  ************************************************************************
3553  *
3554  */
3555 static void filt_hammerdetach(struct knote *kn);
3556 static int filt_hammerread(struct knote *kn, long hint);
3557 static int filt_hammerwrite(struct knote *kn, long hint);
3558 static int filt_hammervnode(struct knote *kn, long hint);
3559 
3560 static struct filterops hammerread_filtops =
3561 	{ FILTEROP_ISFD | FILTEROP_MPSAFE,
3562 	  NULL, filt_hammerdetach, filt_hammerread };
3563 static struct filterops hammerwrite_filtops =
3564 	{ FILTEROP_ISFD | FILTEROP_MPSAFE,
3565 	  NULL, filt_hammerdetach, filt_hammerwrite };
3566 static struct filterops hammervnode_filtops =
3567 	{ FILTEROP_ISFD | FILTEROP_MPSAFE,
3568 	  NULL, filt_hammerdetach, filt_hammervnode };
3569 
3570 static
3571 int
3572 hammer_vop_kqfilter(struct vop_kqfilter_args *ap)
3573 {
3574 	struct vnode *vp = ap->a_vp;
3575 	struct knote *kn = ap->a_kn;
3576 
3577 	switch (kn->kn_filter) {
3578 	case EVFILT_READ:
3579 		kn->kn_fop = &hammerread_filtops;
3580 		break;
3581 	case EVFILT_WRITE:
3582 		kn->kn_fop = &hammerwrite_filtops;
3583 		break;
3584 	case EVFILT_VNODE:
3585 		kn->kn_fop = &hammervnode_filtops;
3586 		break;
3587 	default:
3588 		return (EOPNOTSUPP);
3589 	}
3590 
3591 	kn->kn_hook = (caddr_t)vp;
3592 
3593 	knote_insert(&vp->v_pollinfo.vpi_kqinfo.ki_note, kn);
3594 
3595 	return(0);
3596 }
3597 
3598 static void
3599 filt_hammerdetach(struct knote *kn)
3600 {
3601 	struct vnode *vp = (void *)kn->kn_hook;
3602 
3603 	knote_remove(&vp->v_pollinfo.vpi_kqinfo.ki_note, kn);
3604 }
3605 
3606 static int
3607 filt_hammerread(struct knote *kn, long hint)
3608 {
3609 	struct vnode *vp = (void *)kn->kn_hook;
3610 	hammer_inode_t ip = VTOI(vp);
3611 	hammer_mount_t hmp = ip->hmp;
3612 	off_t off;
3613 
3614 	if (hint == NOTE_REVOKE) {
3615 		kn->kn_flags |= (EV_EOF | EV_NODATA | EV_ONESHOT);
3616 		return(1);
3617 	}
3618 	lwkt_gettoken(&hmp->fs_token);	/* XXX use per-ip-token */
3619 	off = ip->ino_data.size - kn->kn_fp->f_offset;
3620 	kn->kn_data = (off < INTPTR_MAX) ? off : INTPTR_MAX;
3621 	lwkt_reltoken(&hmp->fs_token);
3622 	if (kn->kn_sfflags & NOTE_OLDAPI)
3623 		return(1);
3624 	return (kn->kn_data != 0);
3625 }
3626 
3627 static int
3628 filt_hammerwrite(struct knote *kn, long hint)
3629 {
3630 	if (hint == NOTE_REVOKE)
3631 		kn->kn_flags |= (EV_EOF | EV_NODATA | EV_ONESHOT);
3632 	kn->kn_data = 0;
3633 	return (1);
3634 }
3635 
3636 static int
3637 filt_hammervnode(struct knote *kn, long hint)
3638 {
3639 	if (kn->kn_sfflags & hint)
3640 		kn->kn_fflags |= hint;
3641 	if (hint == NOTE_REVOKE) {
3642 		kn->kn_flags |= (EV_EOF | EV_NODATA);
3643 		return (1);
3644 	}
3645 	return (kn->kn_fflags != 0);
3646 }
3647 
3648