xref: /dragonfly/sys/vfs/hammer/hammer_vnops.c (revision 4d4ae2fa)
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 = HAMMER_XBUFSIZE64_DOALIGN(ip->ino_data.size);
1059 	} else if (ip->ino_data.size > HAMMER_HBUFSIZE) {
1060 		vap->va_bytes = HAMMER_BUFSIZE64_DOALIGN(ip->ino_data.size);
1061 	} else {
1062 		vap->va_bytes = HAMMER_DATA_DOALIGN(ip->ino_data.size);
1063 	}
1064 
1065 	vap->va_type = hammer_get_vnode_type(ip->ino_data.obj_type);
1066 	vap->va_filerev = 0;	/* XXX */
1067 	vap->va_uid_uuid = ip->ino_data.uid;
1068 	vap->va_gid_uuid = ip->ino_data.gid;
1069 	vap->va_fsid_uuid = ip->hmp->fsid;
1070 	vap->va_vaflags = VA_UID_UUID_VALID | VA_GID_UUID_VALID |
1071 			  VA_FSID_UUID_VALID;
1072 
1073 	switch (ip->ino_data.obj_type) {
1074 	case HAMMER_OBJTYPE_CDEV:
1075 	case HAMMER_OBJTYPE_BDEV:
1076 		vap->va_rmajor = ip->ino_data.rmajor;
1077 		vap->va_rminor = ip->ino_data.rminor;
1078 		break;
1079 	default:
1080 		break;
1081 	}
1082 	hammer_unlock(&ip->lock);
1083 	return(0);
1084 }
1085 
1086 /*
1087  * hammer_vop_nresolve { nch, dvp, cred }
1088  *
1089  * Locate the requested directory entry.
1090  */
1091 static
1092 int
1093 hammer_vop_nresolve(struct vop_nresolve_args *ap)
1094 {
1095 	struct hammer_transaction trans;
1096 	struct namecache *ncp;
1097 	hammer_mount_t hmp;
1098 	hammer_inode_t dip;
1099 	hammer_inode_t ip;
1100 	hammer_tid_t asof;
1101 	struct hammer_cursor cursor;
1102 	struct vnode *vp;
1103 	int64_t namekey;
1104 	int error;
1105 	int i;
1106 	int nlen;
1107 	int flags;
1108 	int ispfs;
1109 	int64_t obj_id;
1110 	uint32_t localization;
1111 	uint32_t max_iterations;
1112 
1113 	/*
1114 	 * Misc initialization, plus handle as-of name extensions.  Look for
1115 	 * the '@@' extension.  Note that as-of files and directories cannot
1116 	 * be modified.
1117 	 */
1118 	dip = VTOI(ap->a_dvp);
1119 	ncp = ap->a_nch->ncp;
1120 	asof = dip->obj_asof;
1121 	localization = dip->obj_localization;	/* for code consistency */
1122 	nlen = ncp->nc_nlen;
1123 	flags = dip->flags & HAMMER_INODE_RO;
1124 	ispfs = 0;
1125 	hmp = dip->hmp;
1126 
1127 	lwkt_gettoken(&hmp->fs_token);
1128 	hammer_simple_transaction(&trans, hmp);
1129 	++hammer_stats_file_iopsr;
1130 
1131 	for (i = 0; i < nlen; ++i) {
1132 		if (ncp->nc_name[i] == '@' && ncp->nc_name[i+1] == '@') {
1133 			error = hammer_str_to_tid(ncp->nc_name + i + 2,
1134 						  &ispfs, &asof, &localization);
1135 			if (error != 0) {
1136 				i = nlen;
1137 				break;
1138 			}
1139 			if (asof != HAMMER_MAX_TID)
1140 				flags |= HAMMER_INODE_RO;
1141 			break;
1142 		}
1143 	}
1144 	nlen = i;
1145 
1146 	/*
1147 	 * If this is a PFS softlink we dive into the PFS
1148 	 */
1149 	if (ispfs && nlen == 0) {
1150 		ip = hammer_get_inode(&trans, dip, HAMMER_OBJID_ROOT,
1151 				      asof, localization,
1152 				      flags, &error);
1153 		if (error == 0) {
1154 			error = hammer_get_vnode(ip, &vp);
1155 			hammer_rel_inode(ip, 0);
1156 		} else {
1157 			vp = NULL;
1158 		}
1159 		if (error == 0) {
1160 			vn_unlock(vp);
1161 			cache_setvp(ap->a_nch, vp);
1162 			vrele(vp);
1163 		}
1164 		goto done;
1165 	}
1166 
1167 	/*
1168 	 * If there is no path component the time extension is relative to dip.
1169 	 * e.g. "fubar/@@<snapshot>"
1170 	 *
1171 	 * "." is handled by the kernel, but ".@@<snapshot>" is not.
1172 	 * e.g. "fubar/.@@<snapshot>"
1173 	 *
1174 	 * ".." is handled by the kernel.  We do not currently handle
1175 	 * "..@<snapshot>".
1176 	 */
1177 	if (nlen == 0 || (nlen == 1 && ncp->nc_name[0] == '.')) {
1178 		ip = hammer_get_inode(&trans, dip, dip->obj_id,
1179 				      asof, dip->obj_localization,
1180 				      flags, &error);
1181 		if (error == 0) {
1182 			error = hammer_get_vnode(ip, &vp);
1183 			hammer_rel_inode(ip, 0);
1184 		} else {
1185 			vp = NULL;
1186 		}
1187 		if (error == 0) {
1188 			vn_unlock(vp);
1189 			cache_setvp(ap->a_nch, vp);
1190 			vrele(vp);
1191 		}
1192 		goto done;
1193 	}
1194 
1195 	/*
1196 	 * Calculate the namekey and setup the key range for the scan.  This
1197 	 * works kinda like a chained hash table where the lower 32 bits
1198 	 * of the namekey synthesize the chain.
1199 	 *
1200 	 * The key range is inclusive of both key_beg and key_end.
1201 	 */
1202 	namekey = hammer_direntry_namekey(dip, ncp->nc_name, nlen,
1203 					   &max_iterations);
1204 
1205 	error = hammer_init_cursor(&trans, &cursor, &dip->cache[1], dip);
1206 	cursor.key_beg.localization = dip->obj_localization |
1207 				      hammer_dir_localization(dip);
1208         cursor.key_beg.obj_id = dip->obj_id;
1209 	cursor.key_beg.key = namekey;
1210         cursor.key_beg.create_tid = 0;
1211         cursor.key_beg.delete_tid = 0;
1212         cursor.key_beg.rec_type = HAMMER_RECTYPE_DIRENTRY;
1213         cursor.key_beg.obj_type = 0;
1214 
1215 	cursor.key_end = cursor.key_beg;
1216 	cursor.key_end.key += max_iterations;
1217 	cursor.asof = asof;
1218 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF;
1219 
1220 	/*
1221 	 * Scan all matching records (the chain), locate the one matching
1222 	 * the requested path component.
1223 	 *
1224 	 * The hammer_ip_*() functions merge in-memory records with on-disk
1225 	 * records for the purposes of the search.
1226 	 */
1227 	obj_id = 0;
1228 	localization = HAMMER_DEF_LOCALIZATION;
1229 
1230 	if (error == 0) {
1231 		error = hammer_ip_first(&cursor);
1232 		while (error == 0) {
1233 			error = hammer_ip_resolve_data(&cursor);
1234 			if (error)
1235 				break;
1236 			if (nlen == cursor.leaf->data_len - HAMMER_ENTRY_NAME_OFF &&
1237 			    bcmp(ncp->nc_name, cursor.data->entry.name, nlen) == 0) {
1238 				obj_id = cursor.data->entry.obj_id;
1239 				localization = cursor.data->entry.localization;
1240 				break;
1241 			}
1242 			error = hammer_ip_next(&cursor);
1243 		}
1244 	}
1245 	hammer_done_cursor(&cursor);
1246 
1247 	/*
1248 	 * Lookup the obj_id.  This should always succeed.  If it does not
1249 	 * the filesystem may be damaged and we return a dummy inode.
1250 	 */
1251 	if (error == 0) {
1252 		ip = hammer_get_inode(&trans, dip, obj_id,
1253 				      asof, localization,
1254 				      flags, &error);
1255 		if (error == ENOENT) {
1256 			hkprintf("WARNING: Missing inode for dirent \"%s\"\n"
1257 				"\tobj_id = %016jx, asof=%016jx, lo=%08x\n",
1258 				ncp->nc_name,
1259 				(intmax_t)obj_id, (intmax_t)asof,
1260 				localization);
1261 			error = 0;
1262 			ip = hammer_get_dummy_inode(&trans, dip, obj_id,
1263 						    asof, localization,
1264 						    flags, &error);
1265 		}
1266 		if (error == 0) {
1267 			error = hammer_get_vnode(ip, &vp);
1268 			hammer_rel_inode(ip, 0);
1269 		} else {
1270 			vp = NULL;
1271 		}
1272 		if (error == 0) {
1273 			vn_unlock(vp);
1274 			cache_setvp(ap->a_nch, vp);
1275 			vrele(vp);
1276 		}
1277 	} else if (error == ENOENT) {
1278 		cache_setvp(ap->a_nch, NULL);
1279 	}
1280 done:
1281 	hammer_done_transaction(&trans);
1282 	lwkt_reltoken(&hmp->fs_token);
1283 	return (error);
1284 }
1285 
1286 /*
1287  * hammer_vop_nlookupdotdot { dvp, vpp, cred }
1288  *
1289  * Locate the parent directory of a directory vnode.
1290  *
1291  * dvp is referenced but not locked.  *vpp must be returned referenced and
1292  * locked.  A parent_obj_id of 0 indicates that we are at the root.
1293  *
1294  * NOTE: as-of sequences are not linked into the directory structure.  If
1295  * we are at the root with a different asof then the mount point, reload
1296  * the same directory with the mount point's asof.   I'm not sure what this
1297  * will do to NFS.  We encode ASOF stamps in NFS file handles so it might not
1298  * get confused, but it hasn't been tested.
1299  */
1300 static
1301 int
1302 hammer_vop_nlookupdotdot(struct vop_nlookupdotdot_args *ap)
1303 {
1304 	struct hammer_transaction trans;
1305 	hammer_inode_t dip;
1306 	hammer_inode_t ip;
1307 	hammer_mount_t hmp;
1308 	int64_t parent_obj_id;
1309 	uint32_t parent_obj_localization;
1310 	hammer_tid_t asof;
1311 	int error;
1312 
1313 	dip = VTOI(ap->a_dvp);
1314 	asof = dip->obj_asof;
1315 	hmp = dip->hmp;
1316 
1317 	/*
1318 	 * Whos are parent?  This could be the root of a pseudo-filesystem
1319 	 * whos parent is in another localization domain.
1320 	 */
1321 	lwkt_gettoken(&hmp->fs_token);
1322 	parent_obj_id = dip->ino_data.parent_obj_id;
1323 	if (dip->obj_id == HAMMER_OBJID_ROOT)
1324 		parent_obj_localization = HAMMER_DEF_LOCALIZATION;
1325 	else
1326 		parent_obj_localization = dip->obj_localization;
1327 
1328 	/*
1329 	 * It's probably a PFS root when dip->ino_data.parent_obj_id is 0.
1330 	 */
1331 	if (parent_obj_id == 0) {
1332 		if (dip->obj_id == HAMMER_OBJID_ROOT &&
1333 		   asof != hmp->asof) {
1334 			parent_obj_id = dip->obj_id;
1335 			asof = hmp->asof;
1336 			*ap->a_fakename = kmalloc(19, M_TEMP, M_WAITOK);
1337 			ksnprintf(*ap->a_fakename, 19, "0x%016jx",
1338 				  (intmax_t)dip->obj_asof);
1339 		} else {
1340 			*ap->a_vpp = NULL;
1341 			lwkt_reltoken(&hmp->fs_token);
1342 			return ENOENT;
1343 		}
1344 	}
1345 
1346 	hammer_simple_transaction(&trans, hmp);
1347 	++hammer_stats_file_iopsr;
1348 
1349 	ip = hammer_get_inode(&trans, dip, parent_obj_id,
1350 			      asof, parent_obj_localization,
1351 			      dip->flags, &error);
1352 	if (ip) {
1353 		error = hammer_get_vnode(ip, ap->a_vpp);
1354 		hammer_rel_inode(ip, 0);
1355 	} else {
1356 		*ap->a_vpp = NULL;
1357 	}
1358 	hammer_done_transaction(&trans);
1359 	lwkt_reltoken(&hmp->fs_token);
1360 	return (error);
1361 }
1362 
1363 /*
1364  * hammer_vop_nlink { nch, dvp, vp, cred }
1365  */
1366 static
1367 int
1368 hammer_vop_nlink(struct vop_nlink_args *ap)
1369 {
1370 	struct hammer_transaction trans;
1371 	hammer_inode_t dip;
1372 	hammer_inode_t ip;
1373 	struct nchandle *nch;
1374 	hammer_mount_t hmp;
1375 	int error;
1376 
1377 	if (ap->a_dvp->v_mount != ap->a_vp->v_mount)
1378 		return(EXDEV);
1379 
1380 	nch = ap->a_nch;
1381 	dip = VTOI(ap->a_dvp);
1382 	ip = VTOI(ap->a_vp);
1383 	hmp = dip->hmp;
1384 
1385 	if (dip->obj_localization != ip->obj_localization)
1386 		return(EXDEV);
1387 
1388 	if (dip->flags & HAMMER_INODE_RO)
1389 		return (EROFS);
1390 	if (ip->flags & HAMMER_INODE_RO)
1391 		return (EROFS);
1392 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
1393 		return (error);
1394 
1395 	/*
1396 	 * Create a transaction to cover the operations we perform.
1397 	 */
1398 	lwkt_gettoken(&hmp->fs_token);
1399 	hammer_start_transaction(&trans, hmp);
1400 	++hammer_stats_file_iopsw;
1401 
1402 	/*
1403 	 * Add the filesystem object to the directory.  Note that neither
1404 	 * dip nor ip are referenced or locked, but their vnodes are
1405 	 * referenced.  This function will bump the inode's link count.
1406 	 */
1407 	error = hammer_ip_add_direntry(&trans, dip,
1408 					nch->ncp->nc_name, nch->ncp->nc_nlen,
1409 					ip);
1410 
1411 	/*
1412 	 * Finish up.
1413 	 */
1414 	if (error == 0) {
1415 		cache_setunresolved(nch);
1416 		cache_setvp(nch, ap->a_vp);
1417 	}
1418 	hammer_done_transaction(&trans);
1419 	hammer_knote(ap->a_vp, NOTE_LINK);
1420 	hammer_knote(ap->a_dvp, NOTE_WRITE);
1421 	lwkt_reltoken(&hmp->fs_token);
1422 	return (error);
1423 }
1424 
1425 /*
1426  * hammer_vop_nmkdir { nch, dvp, vpp, cred, vap }
1427  *
1428  * The operating system has already ensured that the directory entry
1429  * does not exist and done all appropriate namespace locking.
1430  */
1431 static
1432 int
1433 hammer_vop_nmkdir(struct vop_nmkdir_args *ap)
1434 {
1435 	struct hammer_transaction trans;
1436 	hammer_inode_t dip;
1437 	hammer_inode_t nip;
1438 	struct nchandle *nch;
1439 	hammer_mount_t hmp;
1440 	int error;
1441 
1442 	nch = ap->a_nch;
1443 	dip = VTOI(ap->a_dvp);
1444 	hmp = dip->hmp;
1445 
1446 	if (dip->flags & HAMMER_INODE_RO)
1447 		return (EROFS);
1448 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
1449 		return (error);
1450 
1451 	/*
1452 	 * Create a transaction to cover the operations we perform.
1453 	 */
1454 	lwkt_gettoken(&hmp->fs_token);
1455 	hammer_start_transaction(&trans, hmp);
1456 	++hammer_stats_file_iopsw;
1457 
1458 	/*
1459 	 * Create a new filesystem object of the requested type.  The
1460 	 * returned inode will be referenced but not locked.
1461 	 */
1462 	error = hammer_create_inode(&trans, ap->a_vap, ap->a_cred,
1463 				    dip, nch->ncp->nc_name, nch->ncp->nc_nlen,
1464 				    NULL, &nip);
1465 	if (error) {
1466 		hammer_done_transaction(&trans);
1467 		*ap->a_vpp = NULL;
1468 		lwkt_reltoken(&hmp->fs_token);
1469 		return (error);
1470 	}
1471 	/*
1472 	 * Add the new filesystem object to the directory.  This will also
1473 	 * bump the inode's link count.
1474 	 */
1475 	error = hammer_ip_add_direntry(&trans, dip,
1476 					nch->ncp->nc_name, nch->ncp->nc_nlen,
1477 					nip);
1478 	if (error)
1479 		hkprintf("hammer_mkdir (add) error %d\n", error);
1480 
1481 	/*
1482 	 * Finish up.
1483 	 */
1484 	if (error) {
1485 		hammer_rel_inode(nip, 0);
1486 		*ap->a_vpp = NULL;
1487 	} else {
1488 		error = hammer_get_vnode(nip, ap->a_vpp);
1489 		hammer_rel_inode(nip, 0);
1490 		if (error == 0) {
1491 			cache_setunresolved(ap->a_nch);
1492 			cache_setvp(ap->a_nch, *ap->a_vpp);
1493 		}
1494 	}
1495 	hammer_done_transaction(&trans);
1496 	if (error == 0)
1497 		hammer_knote(ap->a_dvp, NOTE_WRITE | NOTE_LINK);
1498 	lwkt_reltoken(&hmp->fs_token);
1499 	return (error);
1500 }
1501 
1502 /*
1503  * hammer_vop_nmknod { nch, dvp, vpp, cred, vap }
1504  *
1505  * The operating system has already ensured that the directory entry
1506  * does not exist and done all appropriate namespace locking.
1507  */
1508 static
1509 int
1510 hammer_vop_nmknod(struct vop_nmknod_args *ap)
1511 {
1512 	struct hammer_transaction trans;
1513 	hammer_inode_t dip;
1514 	hammer_inode_t nip;
1515 	struct nchandle *nch;
1516 	hammer_mount_t hmp;
1517 	int error;
1518 
1519 	nch = ap->a_nch;
1520 	dip = VTOI(ap->a_dvp);
1521 	hmp = dip->hmp;
1522 
1523 	if (dip->flags & HAMMER_INODE_RO)
1524 		return (EROFS);
1525 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
1526 		return (error);
1527 
1528 	/*
1529 	 * Create a transaction to cover the operations we perform.
1530 	 */
1531 	lwkt_gettoken(&hmp->fs_token);
1532 	hammer_start_transaction(&trans, hmp);
1533 	++hammer_stats_file_iopsw;
1534 
1535 	/*
1536 	 * Create a new filesystem object of the requested type.  The
1537 	 * returned inode will be referenced but not locked.
1538 	 *
1539 	 * If mknod specifies a directory a pseudo-fs is created.
1540 	 */
1541 	error = hammer_create_inode(&trans, ap->a_vap, ap->a_cred,
1542 				    dip, nch->ncp->nc_name, nch->ncp->nc_nlen,
1543 				    NULL, &nip);
1544 	if (error) {
1545 		hammer_done_transaction(&trans);
1546 		*ap->a_vpp = NULL;
1547 		lwkt_reltoken(&hmp->fs_token);
1548 		return (error);
1549 	}
1550 
1551 	/*
1552 	 * Add the new filesystem object to the directory.  This will also
1553 	 * bump the inode's link count.
1554 	 */
1555 	error = hammer_ip_add_direntry(&trans, dip,
1556 					nch->ncp->nc_name, nch->ncp->nc_nlen,
1557 					nip);
1558 
1559 	/*
1560 	 * Finish up.
1561 	 */
1562 	if (error) {
1563 		hammer_rel_inode(nip, 0);
1564 		*ap->a_vpp = NULL;
1565 	} else {
1566 		error = hammer_get_vnode(nip, ap->a_vpp);
1567 		hammer_rel_inode(nip, 0);
1568 		if (error == 0) {
1569 			cache_setunresolved(ap->a_nch);
1570 			cache_setvp(ap->a_nch, *ap->a_vpp);
1571 		}
1572 	}
1573 	hammer_done_transaction(&trans);
1574 	if (error == 0)
1575 		hammer_knote(ap->a_dvp, NOTE_WRITE);
1576 	lwkt_reltoken(&hmp->fs_token);
1577 	return (error);
1578 }
1579 
1580 /*
1581  * hammer_vop_open { vp, mode, cred, fp }
1582  *
1583  * MPSAFE (does not require fs_token)
1584  */
1585 static
1586 int
1587 hammer_vop_open(struct vop_open_args *ap)
1588 {
1589 	hammer_inode_t ip;
1590 
1591 	++hammer_stats_file_iopsr;
1592 	ip = VTOI(ap->a_vp);
1593 
1594 	if ((ap->a_mode & FWRITE) && (ip->flags & HAMMER_INODE_RO))
1595 		return (EROFS);
1596 	return(vop_stdopen(ap));
1597 }
1598 
1599 /*
1600  * hammer_vop_print { vp }
1601  */
1602 static
1603 int
1604 hammer_vop_print(struct vop_print_args *ap)
1605 {
1606 	return EOPNOTSUPP;
1607 }
1608 
1609 /*
1610  * hammer_vop_readdir { vp, uio, cred, *eofflag, *ncookies, off_t **cookies }
1611  */
1612 static
1613 int
1614 hammer_vop_readdir(struct vop_readdir_args *ap)
1615 {
1616 	struct hammer_transaction trans;
1617 	struct hammer_cursor cursor;
1618 	hammer_inode_t ip;
1619 	hammer_mount_t hmp;
1620 	struct uio *uio;
1621 	hammer_base_elm_t base;
1622 	int error;
1623 	int cookie_index;
1624 	int ncookies;
1625 	off_t *cookies;
1626 	off_t saveoff;
1627 	int r;
1628 	int dtype;
1629 
1630 	++hammer_stats_file_iopsr;
1631 	ip = VTOI(ap->a_vp);
1632 	uio = ap->a_uio;
1633 	saveoff = uio->uio_offset;
1634 	hmp = ip->hmp;
1635 
1636 	if (ap->a_ncookies) {
1637 		ncookies = uio->uio_resid / 16 + 1;
1638 		if (ncookies > 1024)
1639 			ncookies = 1024;
1640 		cookies = kmalloc(ncookies * sizeof(off_t), M_TEMP, M_WAITOK);
1641 		cookie_index = 0;
1642 	} else {
1643 		ncookies = -1;
1644 		cookies = NULL;
1645 		cookie_index = 0;
1646 	}
1647 
1648 	lwkt_gettoken(&hmp->fs_token);
1649 	hammer_simple_transaction(&trans, hmp);
1650 
1651 	/*
1652 	 * Handle artificial entries
1653 	 *
1654 	 * It should be noted that the minimum value for a directory
1655 	 * hash key on-media is 0x0000000100000000, so we can use anything
1656 	 * less then that to represent our 'special' key space.
1657 	 */
1658 	error = 0;
1659 	if (saveoff == 0) {
1660 		r = vop_write_dirent(&error, uio, ip->obj_id, DT_DIR, 1, ".");
1661 		if (r)
1662 			goto done;
1663 		if (cookies)
1664 			cookies[cookie_index] = saveoff;
1665 		++saveoff;
1666 		++cookie_index;
1667 		if (cookie_index == ncookies)
1668 			goto done;
1669 	}
1670 	if (saveoff == 1) {
1671 		if (ip->ino_data.parent_obj_id) {
1672 			r = vop_write_dirent(&error, uio,
1673 					     ip->ino_data.parent_obj_id,
1674 					     DT_DIR, 2, "..");
1675 		} else {
1676 			r = vop_write_dirent(&error, uio,
1677 					     ip->obj_id, DT_DIR, 2, "..");
1678 		}
1679 		if (r)
1680 			goto done;
1681 		if (cookies)
1682 			cookies[cookie_index] = saveoff;
1683 		++saveoff;
1684 		++cookie_index;
1685 		if (cookie_index == ncookies)
1686 			goto done;
1687 	}
1688 
1689 	/*
1690 	 * Key range (begin and end inclusive) to scan.  Directory keys
1691 	 * directly translate to a 64 bit 'seek' position.
1692 	 */
1693 	hammer_init_cursor(&trans, &cursor, &ip->cache[1], ip);
1694 	cursor.key_beg.localization = ip->obj_localization |
1695 				      hammer_dir_localization(ip);
1696 	cursor.key_beg.obj_id = ip->obj_id;
1697 	cursor.key_beg.create_tid = 0;
1698 	cursor.key_beg.delete_tid = 0;
1699         cursor.key_beg.rec_type = HAMMER_RECTYPE_DIRENTRY;
1700 	cursor.key_beg.obj_type = 0;
1701 	cursor.key_beg.key = saveoff;
1702 
1703 	cursor.key_end = cursor.key_beg;
1704 	cursor.key_end.key = HAMMER_MAX_KEY;
1705 	cursor.asof = ip->obj_asof;
1706 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF;
1707 
1708 	error = hammer_ip_first(&cursor);
1709 
1710 	while (error == 0) {
1711 		error = hammer_ip_resolve_data(&cursor);
1712 		if (error)
1713 			break;
1714 		base = &cursor.leaf->base;
1715 		saveoff = base->key;
1716 		KKASSERT(cursor.leaf->data_len > HAMMER_ENTRY_NAME_OFF);
1717 
1718 		if (base->obj_id != ip->obj_id)
1719 			hpanic("bad record at %p", cursor.node);
1720 
1721 		dtype = hammer_get_dtype(cursor.leaf->base.obj_type);
1722 		r = vop_write_dirent(
1723 			     &error, uio, cursor.data->entry.obj_id,
1724 			     dtype,
1725 			     cursor.leaf->data_len - HAMMER_ENTRY_NAME_OFF ,
1726 			     (void *)cursor.data->entry.name);
1727 		if (r)
1728 			break;
1729 		++saveoff;
1730 		if (cookies)
1731 			cookies[cookie_index] = base->key;
1732 		++cookie_index;
1733 		if (cookie_index == ncookies)
1734 			break;
1735 		error = hammer_ip_next(&cursor);
1736 	}
1737 	hammer_done_cursor(&cursor);
1738 
1739 done:
1740 	hammer_done_transaction(&trans);
1741 
1742 	if (ap->a_eofflag)
1743 		*ap->a_eofflag = (error == ENOENT);
1744 	uio->uio_offset = saveoff;
1745 	if (error && cookie_index == 0) {
1746 		if (error == ENOENT)
1747 			error = 0;
1748 		if (cookies) {
1749 			kfree(cookies, M_TEMP);
1750 			*ap->a_ncookies = 0;
1751 			*ap->a_cookies = NULL;
1752 		}
1753 	} else {
1754 		if (error == ENOENT)
1755 			error = 0;
1756 		if (cookies) {
1757 			*ap->a_ncookies = cookie_index;
1758 			*ap->a_cookies = cookies;
1759 		}
1760 	}
1761 	lwkt_reltoken(&hmp->fs_token);
1762 	return(error);
1763 }
1764 
1765 /*
1766  * hammer_vop_readlink { vp, uio, cred }
1767  */
1768 static
1769 int
1770 hammer_vop_readlink(struct vop_readlink_args *ap)
1771 {
1772 	struct hammer_transaction trans;
1773 	struct hammer_cursor cursor;
1774 	hammer_inode_t ip;
1775 	hammer_mount_t hmp;
1776 	char buf[32];
1777 	uint32_t localization;
1778 	hammer_pseudofs_inmem_t pfsm;
1779 	int error;
1780 
1781 	ip = VTOI(ap->a_vp);
1782 	hmp = ip->hmp;
1783 
1784 	lwkt_gettoken(&hmp->fs_token);
1785 
1786 	/*
1787 	 * Shortcut if the symlink data was stuffed into ino_data.
1788 	 *
1789 	 * Also expand special "@@PFS%05d" softlinks (expansion only
1790 	 * occurs for non-historical (current) accesses made from the
1791 	 * primary filesystem).
1792 	 *
1793 	 * Note that userspace hammer command does not allow users to
1794 	 * create a @@PFS softlink under an existing other PFS (id!=0)
1795 	 * so the ip localization here for @@PFS softlink is always 0.
1796 	 */
1797 	if (ip->ino_data.size <= HAMMER_INODE_BASESYMLEN) {
1798 		char *ptr;
1799 		int bytes;
1800 
1801 		ptr = ip->ino_data.ext.symlink;
1802 		bytes = (int)ip->ino_data.size;
1803 		if (bytes == 10 &&
1804 		    ip->obj_asof == HAMMER_MAX_TID &&
1805 		    ip->obj_localization == HAMMER_DEF_LOCALIZATION &&
1806 		    strncmp(ptr, "@@PFS", 5) == 0) {
1807 			hammer_simple_transaction(&trans, hmp);
1808 			bcopy(ptr + 5, buf, 5);
1809 			buf[5] = 0;
1810 			localization = pfs_to_lo(strtoul(buf, NULL, 10));
1811 			pfsm = hammer_load_pseudofs(&trans, localization,
1812 						    &error);
1813 			if (error == 0) {
1814 				if (hammer_is_pfs_slave(&pfsm->pfsd)) {
1815 					/* vap->va_size == 26 */
1816 					ksnprintf(buf, sizeof(buf),
1817 						  "@@0x%016jx:%05d",
1818 						  (intmax_t)pfsm->pfsd.sync_end_tid,
1819 						  lo_to_pfs(localization));
1820 				} else {
1821 					/* vap->va_size == 10 */
1822 					ksnprintf(buf, sizeof(buf),
1823 						  "@@-1:%05d",
1824 						  lo_to_pfs(localization));
1825 				}
1826 				ptr = buf;
1827 				bytes = strlen(buf);
1828 			}
1829 			if (pfsm)
1830 				hammer_rel_pseudofs(hmp, pfsm);
1831 			hammer_done_transaction(&trans);
1832 		}
1833 		error = uiomove(ptr, bytes, ap->a_uio);
1834 		lwkt_reltoken(&hmp->fs_token);
1835 		return(error);
1836 	}
1837 
1838 	/*
1839 	 * Long version
1840 	 */
1841 	hammer_simple_transaction(&trans, hmp);
1842 	++hammer_stats_file_iopsr;
1843 	hammer_init_cursor(&trans, &cursor, &ip->cache[1], ip);
1844 
1845 	/*
1846 	 * Key range (begin and end inclusive) to scan.  Directory keys
1847 	 * directly translate to a 64 bit 'seek' position.
1848 	 */
1849 	cursor.key_beg.localization = ip->obj_localization |
1850 				      HAMMER_LOCALIZE_MISC;
1851 	cursor.key_beg.obj_id = ip->obj_id;
1852 	cursor.key_beg.create_tid = 0;
1853 	cursor.key_beg.delete_tid = 0;
1854         cursor.key_beg.rec_type = HAMMER_RECTYPE_FIX;
1855 	cursor.key_beg.obj_type = 0;
1856 	cursor.key_beg.key = HAMMER_FIXKEY_SYMLINK;
1857 	cursor.asof = ip->obj_asof;
1858 	cursor.flags |= HAMMER_CURSOR_ASOF;
1859 
1860 	error = hammer_ip_lookup(&cursor);
1861 	if (error == 0) {
1862 		error = hammer_ip_resolve_data(&cursor);
1863 		if (error == 0) {
1864 			KKASSERT(cursor.leaf->data_len >=
1865 				 HAMMER_SYMLINK_NAME_OFF);
1866 			error = uiomove(cursor.data->symlink.name,
1867 					cursor.leaf->data_len -
1868 						HAMMER_SYMLINK_NAME_OFF,
1869 					ap->a_uio);
1870 		}
1871 	}
1872 	hammer_done_cursor(&cursor);
1873 	hammer_done_transaction(&trans);
1874 	lwkt_reltoken(&hmp->fs_token);
1875 	return(error);
1876 }
1877 
1878 /*
1879  * hammer_vop_nremove { nch, dvp, cred }
1880  */
1881 static
1882 int
1883 hammer_vop_nremove(struct vop_nremove_args *ap)
1884 {
1885 	struct hammer_transaction trans;
1886 	hammer_inode_t dip;
1887 	hammer_mount_t hmp;
1888 	int error;
1889 
1890 	dip = VTOI(ap->a_dvp);
1891 	hmp = dip->hmp;
1892 
1893 	if (hammer_nohistory(dip) == 0 &&
1894 	    (error = hammer_checkspace(hmp, HAMMER_CHKSPC_REMOVE)) != 0) {
1895 		return (error);
1896 	}
1897 
1898 	lwkt_gettoken(&hmp->fs_token);
1899 	hammer_start_transaction(&trans, hmp);
1900 	++hammer_stats_file_iopsw;
1901 	error = hammer_dounlink(&trans, ap->a_nch, ap->a_dvp, ap->a_cred, 0, 0);
1902 	hammer_done_transaction(&trans);
1903 	if (error == 0)
1904 		hammer_knote(ap->a_dvp, NOTE_WRITE);
1905 	lwkt_reltoken(&hmp->fs_token);
1906 	return (error);
1907 }
1908 
1909 /*
1910  * hammer_vop_nrename { fnch, tnch, fdvp, tdvp, cred }
1911  */
1912 static
1913 int
1914 hammer_vop_nrename(struct vop_nrename_args *ap)
1915 {
1916 	struct hammer_transaction trans;
1917 	struct namecache *fncp;
1918 	struct namecache *tncp;
1919 	hammer_inode_t fdip;
1920 	hammer_inode_t tdip;
1921 	hammer_inode_t ip;
1922 	hammer_mount_t hmp;
1923 	struct hammer_cursor cursor;
1924 	int64_t namekey;
1925 	uint32_t max_iterations;
1926 	int nlen, error;
1927 
1928 	if (ap->a_fdvp->v_mount != ap->a_tdvp->v_mount)
1929 		return(EXDEV);
1930 	if (ap->a_fdvp->v_mount != ap->a_fnch->ncp->nc_vp->v_mount)
1931 		return(EXDEV);
1932 
1933 	fdip = VTOI(ap->a_fdvp);
1934 	tdip = VTOI(ap->a_tdvp);
1935 	fncp = ap->a_fnch->ncp;
1936 	tncp = ap->a_tnch->ncp;
1937 	ip = VTOI(fncp->nc_vp);
1938 	KKASSERT(ip != NULL);
1939 
1940 	hmp = ip->hmp;
1941 
1942 	if (fdip->obj_localization != tdip->obj_localization)
1943 		return(EXDEV);
1944 	if (fdip->obj_localization != ip->obj_localization)
1945 		return(EXDEV);
1946 
1947 	if (fdip->flags & HAMMER_INODE_RO)
1948 		return (EROFS);
1949 	if (tdip->flags & HAMMER_INODE_RO)
1950 		return (EROFS);
1951 	if (ip->flags & HAMMER_INODE_RO)
1952 		return (EROFS);
1953 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
1954 		return (error);
1955 
1956 	lwkt_gettoken(&hmp->fs_token);
1957 	hammer_start_transaction(&trans, hmp);
1958 	++hammer_stats_file_iopsw;
1959 
1960 	/*
1961 	 * Remove tncp from the target directory and then link ip as
1962 	 * tncp. XXX pass trans to dounlink
1963 	 *
1964 	 * Force the inode sync-time to match the transaction so it is
1965 	 * in-sync with the creation of the target directory entry.
1966 	 */
1967 	error = hammer_dounlink(&trans, ap->a_tnch, ap->a_tdvp,
1968 				ap->a_cred, 0, -1);
1969 	if (error == 0 || error == ENOENT) {
1970 		error = hammer_ip_add_direntry(&trans, tdip,
1971 						tncp->nc_name, tncp->nc_nlen,
1972 						ip);
1973 		if (error == 0) {
1974 			ip->ino_data.parent_obj_id = tdip->obj_id;
1975 			ip->ino_data.ctime = trans.time;
1976 			hammer_modify_inode(&trans, ip, HAMMER_INODE_DDIRTY);
1977 		}
1978 	}
1979 	if (error)
1980 		goto failed; /* XXX */
1981 
1982 	/*
1983 	 * Locate the record in the originating directory and remove it.
1984 	 *
1985 	 * Calculate the namekey and setup the key range for the scan.  This
1986 	 * works kinda like a chained hash table where the lower 32 bits
1987 	 * of the namekey synthesize the chain.
1988 	 *
1989 	 * The key range is inclusive of both key_beg and key_end.
1990 	 */
1991 	namekey = hammer_direntry_namekey(fdip, fncp->nc_name, fncp->nc_nlen,
1992 					   &max_iterations);
1993 retry:
1994 	hammer_init_cursor(&trans, &cursor, &fdip->cache[1], fdip);
1995 	cursor.key_beg.localization = fdip->obj_localization |
1996 				      hammer_dir_localization(fdip);
1997         cursor.key_beg.obj_id = fdip->obj_id;
1998 	cursor.key_beg.key = namekey;
1999         cursor.key_beg.create_tid = 0;
2000         cursor.key_beg.delete_tid = 0;
2001         cursor.key_beg.rec_type = HAMMER_RECTYPE_DIRENTRY;
2002         cursor.key_beg.obj_type = 0;
2003 
2004 	cursor.key_end = cursor.key_beg;
2005 	cursor.key_end.key += max_iterations;
2006 	cursor.asof = fdip->obj_asof;
2007 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF;
2008 
2009 	/*
2010 	 * Scan all matching records (the chain), locate the one matching
2011 	 * the requested path component.
2012 	 *
2013 	 * The hammer_ip_*() functions merge in-memory records with on-disk
2014 	 * records for the purposes of the search.
2015 	 */
2016 	error = hammer_ip_first(&cursor);
2017 	while (error == 0) {
2018 		if (hammer_ip_resolve_data(&cursor) != 0)
2019 			break;
2020 		nlen = cursor.leaf->data_len - HAMMER_ENTRY_NAME_OFF;
2021 		KKASSERT(nlen > 0);
2022 		if (fncp->nc_nlen == nlen &&
2023 		    bcmp(fncp->nc_name, cursor.data->entry.name, nlen) == 0) {
2024 			break;
2025 		}
2026 		error = hammer_ip_next(&cursor);
2027 	}
2028 
2029 	/*
2030 	 * If all is ok we have to get the inode so we can adjust nlinks.
2031 	 *
2032 	 * WARNING: hammer_ip_del_direntry() may have to terminate the
2033 	 * cursor to avoid a recursion.  It's ok to call hammer_done_cursor()
2034 	 * twice.
2035 	 */
2036 	if (error == 0)
2037 		error = hammer_ip_del_direntry(&trans, &cursor, fdip, ip);
2038 
2039 	/*
2040 	 * XXX A deadlock here will break rename's atomicy for the purposes
2041 	 * of crash recovery.
2042 	 */
2043 	if (error == EDEADLK) {
2044 		hammer_done_cursor(&cursor);
2045 		goto retry;
2046 	}
2047 
2048 	/*
2049 	 * Cleanup and tell the kernel that the rename succeeded.
2050 	 *
2051 	 * NOTE: ip->vp, if non-NULL, cannot be directly referenced
2052 	 *	 without formally acquiring the vp since the vp might
2053 	 *	 have zero refs on it, or in the middle of a reclaim,
2054 	 *	 etc.
2055 	 */
2056         hammer_done_cursor(&cursor);
2057 	if (error == 0) {
2058 		cache_rename(ap->a_fnch, ap->a_tnch);
2059 		hammer_knote(ap->a_fdvp, NOTE_WRITE);
2060 		hammer_knote(ap->a_tdvp, NOTE_WRITE);
2061 		while (ip->vp) {
2062 			struct vnode *vp;
2063 
2064 			error = hammer_get_vnode(ip, &vp);
2065 			if (error == 0 && vp) {
2066 				vn_unlock(vp);
2067 				hammer_knote(ip->vp, NOTE_RENAME);
2068 				vrele(vp);
2069 				break;
2070 			}
2071 			hdkprintf("ip/vp race2 avoided\n");
2072 		}
2073 	}
2074 
2075 failed:
2076 	hammer_done_transaction(&trans);
2077 	lwkt_reltoken(&hmp->fs_token);
2078 	return (error);
2079 }
2080 
2081 /*
2082  * hammer_vop_nrmdir { nch, dvp, cred }
2083  */
2084 static
2085 int
2086 hammer_vop_nrmdir(struct vop_nrmdir_args *ap)
2087 {
2088 	struct hammer_transaction trans;
2089 	hammer_inode_t dip;
2090 	hammer_mount_t hmp;
2091 	int error;
2092 
2093 	dip = VTOI(ap->a_dvp);
2094 	hmp = dip->hmp;
2095 
2096 	if (hammer_nohistory(dip) == 0 &&
2097 	    (error = hammer_checkspace(hmp, HAMMER_CHKSPC_REMOVE)) != 0) {
2098 		return (error);
2099 	}
2100 
2101 	lwkt_gettoken(&hmp->fs_token);
2102 	hammer_start_transaction(&trans, hmp);
2103 	++hammer_stats_file_iopsw;
2104 	error = hammer_dounlink(&trans, ap->a_nch, ap->a_dvp, ap->a_cred, 0, 1);
2105 	hammer_done_transaction(&trans);
2106 	if (error == 0)
2107 		hammer_knote(ap->a_dvp, NOTE_WRITE | NOTE_LINK);
2108 	lwkt_reltoken(&hmp->fs_token);
2109 	return (error);
2110 }
2111 
2112 /*
2113  * hammer_vop_markatime { vp, cred }
2114  */
2115 static
2116 int
2117 hammer_vop_markatime(struct vop_markatime_args *ap)
2118 {
2119 	struct hammer_transaction trans;
2120 	hammer_inode_t ip;
2121 	hammer_mount_t hmp;
2122 
2123 	ip = VTOI(ap->a_vp);
2124 	if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY)
2125 		return (EROFS);
2126 	if (ip->flags & HAMMER_INODE_RO)
2127 		return (EROFS);
2128 	hmp = ip->hmp;
2129 	if (hmp->mp->mnt_flag & MNT_NOATIME)
2130 		return (0);
2131 	lwkt_gettoken(&hmp->fs_token);
2132 	hammer_start_transaction(&trans, hmp);
2133 	++hammer_stats_file_iopsw;
2134 
2135 	ip->ino_data.atime = trans.time;
2136 	hammer_modify_inode(&trans, ip, HAMMER_INODE_ATIME);
2137 	hammer_done_transaction(&trans);
2138 	hammer_knote(ap->a_vp, NOTE_ATTRIB);
2139 	lwkt_reltoken(&hmp->fs_token);
2140 	return (0);
2141 }
2142 
2143 /*
2144  * hammer_vop_setattr { vp, vap, cred }
2145  */
2146 static
2147 int
2148 hammer_vop_setattr(struct vop_setattr_args *ap)
2149 {
2150 	struct hammer_transaction trans;
2151 	hammer_inode_t ip;
2152 	struct vattr *vap;
2153 	hammer_mount_t hmp;
2154 	int modflags;
2155 	int error;
2156 	int truncating;
2157 	int blksize;
2158 	int kflags;
2159 #if 0
2160 	int64_t aligned_size;
2161 #endif
2162 	uint32_t flags;
2163 
2164 	vap = ap->a_vap;
2165 	ip = ap->a_vp->v_data;
2166 	modflags = 0;
2167 	kflags = 0;
2168 	hmp = ip->hmp;
2169 
2170 	if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY)
2171 		return(EROFS);
2172 	if (ip->flags & HAMMER_INODE_RO)
2173 		return (EROFS);
2174 	if (hammer_nohistory(ip) == 0 &&
2175 	    (error = hammer_checkspace(hmp, HAMMER_CHKSPC_REMOVE)) != 0) {
2176 		return (error);
2177 	}
2178 
2179 	lwkt_gettoken(&hmp->fs_token);
2180 	hammer_start_transaction(&trans, hmp);
2181 	++hammer_stats_file_iopsw;
2182 	error = 0;
2183 
2184 	if (vap->va_flags != VNOVAL) {
2185 		flags = ip->ino_data.uflags;
2186 		error = vop_helper_setattr_flags(&flags, vap->va_flags,
2187 					 hammer_to_unix_xid(&ip->ino_data.uid),
2188 					 ap->a_cred);
2189 		if (error == 0) {
2190 			if (ip->ino_data.uflags != flags) {
2191 				ip->ino_data.uflags = flags;
2192 				ip->ino_data.ctime = trans.time;
2193 				modflags |= HAMMER_INODE_DDIRTY;
2194 				kflags |= NOTE_ATTRIB;
2195 			}
2196 			if (ip->ino_data.uflags & (IMMUTABLE | APPEND)) {
2197 				error = 0;
2198 				goto done;
2199 			}
2200 		}
2201 		goto done;
2202 	}
2203 	if (ip->ino_data.uflags & (IMMUTABLE | APPEND)) {
2204 		error = EPERM;
2205 		goto done;
2206 	}
2207 	if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) {
2208 		mode_t cur_mode = ip->ino_data.mode;
2209 		uid_t cur_uid = hammer_to_unix_xid(&ip->ino_data.uid);
2210 		gid_t cur_gid = hammer_to_unix_xid(&ip->ino_data.gid);
2211 		uuid_t uuid_uid;
2212 		uuid_t uuid_gid;
2213 
2214 		error = vop_helper_chown(ap->a_vp, vap->va_uid, vap->va_gid,
2215 					 ap->a_cred,
2216 					 &cur_uid, &cur_gid, &cur_mode);
2217 		if (error == 0) {
2218 			hammer_guid_to_uuid(&uuid_uid, cur_uid);
2219 			hammer_guid_to_uuid(&uuid_gid, cur_gid);
2220 			if (bcmp(&uuid_uid, &ip->ino_data.uid,
2221 				 sizeof(uuid_uid)) ||
2222 			    bcmp(&uuid_gid, &ip->ino_data.gid,
2223 				 sizeof(uuid_gid)) ||
2224 			    ip->ino_data.mode != cur_mode) {
2225 				ip->ino_data.uid = uuid_uid;
2226 				ip->ino_data.gid = uuid_gid;
2227 				ip->ino_data.mode = cur_mode;
2228 				ip->ino_data.ctime = trans.time;
2229 				modflags |= HAMMER_INODE_DDIRTY;
2230 			}
2231 			kflags |= NOTE_ATTRIB;
2232 		}
2233 	}
2234 	while (vap->va_size != VNOVAL && ip->ino_data.size != vap->va_size) {
2235 		switch(ap->a_vp->v_type) {
2236 		case VREG:
2237 			if (vap->va_size == ip->ino_data.size)
2238 				break;
2239 
2240 			/*
2241 			 * Log the operation if in fast-fsync mode or if
2242 			 * there are unterminated redo write records present.
2243 			 *
2244 			 * The second check is needed so the recovery code
2245 			 * properly truncates write redos even if nominal
2246 			 * REDO operations is turned off due to excessive
2247 			 * writes, because the related records might be
2248 			 * destroyed and never lay down a TERM_WRITE.
2249 			 */
2250 			if ((ip->flags & HAMMER_INODE_REDO) ||
2251 			    (ip->flags & HAMMER_INODE_RDIRTY)) {
2252 				error = hammer_generate_redo(&trans, ip,
2253 							     vap->va_size,
2254 							     HAMMER_REDO_TRUNC,
2255 							     NULL, 0);
2256 			}
2257 			blksize = hammer_blocksize(vap->va_size);
2258 
2259 			/*
2260 			 * XXX break atomicy, we can deadlock the backend
2261 			 * if we do not release the lock.  Probably not a
2262 			 * big deal here.
2263 			 */
2264 			if (vap->va_size < ip->ino_data.size) {
2265 				nvtruncbuf(ap->a_vp, vap->va_size,
2266 					   blksize,
2267 					   hammer_blockoff(vap->va_size),
2268 					   0);
2269 				truncating = 1;
2270 				kflags |= NOTE_WRITE;
2271 			} else {
2272 				nvextendbuf(ap->a_vp,
2273 					    ip->ino_data.size,
2274 					    vap->va_size,
2275 					    hammer_blocksize(ip->ino_data.size),
2276 					    hammer_blocksize(vap->va_size),
2277 					    hammer_blockoff(ip->ino_data.size),
2278 					    hammer_blockoff(vap->va_size),
2279 					    0);
2280 				truncating = 0;
2281 				kflags |= NOTE_WRITE | NOTE_EXTEND;
2282 			}
2283 			ip->ino_data.size = vap->va_size;
2284 			ip->ino_data.mtime = trans.time;
2285 			/* XXX safe to use SDIRTY instead of DDIRTY here? */
2286 			modflags |= HAMMER_INODE_MTIME | HAMMER_INODE_DDIRTY;
2287 
2288 			/*
2289 			 * On-media truncation is cached in the inode until
2290 			 * the inode is synchronized.  We must immediately
2291 			 * handle any frontend records.
2292 			 */
2293 			if (truncating) {
2294 				hammer_ip_frontend_trunc(ip, vap->va_size);
2295 				if ((ip->flags & HAMMER_INODE_TRUNCATED) == 0) {
2296 					ip->flags |= HAMMER_INODE_TRUNCATED;
2297 					ip->trunc_off = vap->va_size;
2298 					hammer_inode_dirty(ip);
2299 				} else if (ip->trunc_off > vap->va_size) {
2300 					ip->trunc_off = vap->va_size;
2301 				}
2302 			}
2303 
2304 #if 0
2305 			/*
2306 			 * When truncating, nvtruncbuf() may have cleaned out
2307 			 * a portion of the last block on-disk in the buffer
2308 			 * cache.  We must clean out any frontend records
2309 			 * for blocks beyond the new last block.
2310 			 */
2311 			aligned_size = (vap->va_size + (blksize - 1)) &
2312 				       ~(int64_t)(blksize - 1);
2313 			if (truncating && vap->va_size < aligned_size) {
2314 				aligned_size -= blksize;
2315 				hammer_ip_frontend_trunc(ip, aligned_size);
2316 			}
2317 #endif
2318 			break;
2319 		case VDATABASE:
2320 			if ((ip->flags & HAMMER_INODE_TRUNCATED) == 0) {
2321 				ip->flags |= HAMMER_INODE_TRUNCATED;
2322 				ip->trunc_off = vap->va_size;
2323 				hammer_inode_dirty(ip);
2324 			} else if (ip->trunc_off > vap->va_size) {
2325 				ip->trunc_off = vap->va_size;
2326 			}
2327 			hammer_ip_frontend_trunc(ip, vap->va_size);
2328 			ip->ino_data.size = vap->va_size;
2329 			ip->ino_data.mtime = trans.time;
2330 			modflags |= HAMMER_INODE_MTIME | HAMMER_INODE_DDIRTY;
2331 			kflags |= NOTE_ATTRIB;
2332 			break;
2333 		default:
2334 			error = EINVAL;
2335 			goto done;
2336 		}
2337 		break;
2338 	}
2339 	if (vap->va_atime.tv_sec != VNOVAL) {
2340 		ip->ino_data.atime = hammer_timespec_to_time(&vap->va_atime);
2341 		modflags |= HAMMER_INODE_ATIME;
2342 		kflags |= NOTE_ATTRIB;
2343 	}
2344 	if (vap->va_mtime.tv_sec != VNOVAL) {
2345 		ip->ino_data.mtime = hammer_timespec_to_time(&vap->va_mtime);
2346 		modflags |= HAMMER_INODE_MTIME;
2347 		kflags |= NOTE_ATTRIB;
2348 	}
2349 	if (vap->va_mode != (mode_t)VNOVAL) {
2350 		mode_t   cur_mode = ip->ino_data.mode;
2351 		uid_t cur_uid = hammer_to_unix_xid(&ip->ino_data.uid);
2352 		gid_t cur_gid = hammer_to_unix_xid(&ip->ino_data.gid);
2353 
2354 		error = vop_helper_chmod(ap->a_vp, vap->va_mode, ap->a_cred,
2355 					 cur_uid, cur_gid, &cur_mode);
2356 		if (error == 0 && ip->ino_data.mode != cur_mode) {
2357 			ip->ino_data.mode = cur_mode;
2358 			ip->ino_data.ctime = trans.time;
2359 			modflags |= HAMMER_INODE_DDIRTY;
2360 			kflags |= NOTE_ATTRIB;
2361 		}
2362 	}
2363 done:
2364 	if (error == 0)
2365 		hammer_modify_inode(&trans, ip, modflags);
2366 	hammer_done_transaction(&trans);
2367 	hammer_knote(ap->a_vp, kflags);
2368 	lwkt_reltoken(&hmp->fs_token);
2369 	return (error);
2370 }
2371 
2372 /*
2373  * hammer_vop_nsymlink { nch, dvp, vpp, cred, vap, target }
2374  */
2375 static
2376 int
2377 hammer_vop_nsymlink(struct vop_nsymlink_args *ap)
2378 {
2379 	struct hammer_transaction trans;
2380 	hammer_inode_t dip;
2381 	hammer_inode_t nip;
2382 	hammer_record_t record;
2383 	struct nchandle *nch;
2384 	hammer_mount_t hmp;
2385 	int error;
2386 	int bytes;
2387 
2388 	ap->a_vap->va_type = VLNK;
2389 
2390 	nch = ap->a_nch;
2391 	dip = VTOI(ap->a_dvp);
2392 	hmp = dip->hmp;
2393 
2394 	if (dip->flags & HAMMER_INODE_RO)
2395 		return (EROFS);
2396 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
2397 		return (error);
2398 
2399 	/*
2400 	 * Create a transaction to cover the operations we perform.
2401 	 */
2402 	lwkt_gettoken(&hmp->fs_token);
2403 	hammer_start_transaction(&trans, hmp);
2404 	++hammer_stats_file_iopsw;
2405 
2406 	/*
2407 	 * Create a new filesystem object of the requested type.  The
2408 	 * returned inode will be referenced but not locked.
2409 	 */
2410 
2411 	error = hammer_create_inode(&trans, ap->a_vap, ap->a_cred,
2412 				    dip, nch->ncp->nc_name, nch->ncp->nc_nlen,
2413 				    NULL, &nip);
2414 	if (error) {
2415 		hammer_done_transaction(&trans);
2416 		*ap->a_vpp = NULL;
2417 		lwkt_reltoken(&hmp->fs_token);
2418 		return (error);
2419 	}
2420 
2421 	/*
2422 	 * Add a record representing the symlink.  symlink stores the link
2423 	 * as pure data, not a string, and is no \0 terminated.
2424 	 */
2425 	if (error == 0) {
2426 		bytes = strlen(ap->a_target);
2427 
2428 		if (bytes <= HAMMER_INODE_BASESYMLEN) {
2429 			bcopy(ap->a_target, nip->ino_data.ext.symlink, bytes);
2430 		} else {
2431 			record = hammer_alloc_mem_record(nip, bytes);
2432 			record->type = HAMMER_MEM_RECORD_GENERAL;
2433 
2434 			record->leaf.base.localization = nip->obj_localization |
2435 							 HAMMER_LOCALIZE_MISC;
2436 			record->leaf.base.key = HAMMER_FIXKEY_SYMLINK;
2437 			record->leaf.base.rec_type = HAMMER_RECTYPE_FIX;
2438 			record->leaf.data_len = bytes;
2439 			KKASSERT(HAMMER_SYMLINK_NAME_OFF == 0);
2440 			bcopy(ap->a_target, record->data->symlink.name, bytes);
2441 			error = hammer_ip_add_record(&trans, record);
2442 		}
2443 
2444 		/*
2445 		 * Set the file size to the length of the link.
2446 		 */
2447 		if (error == 0) {
2448 			nip->ino_data.size = bytes;
2449 			hammer_modify_inode(&trans, nip, HAMMER_INODE_DDIRTY);
2450 		}
2451 	}
2452 	if (error == 0)
2453 		error = hammer_ip_add_direntry(&trans, dip, nch->ncp->nc_name,
2454 						nch->ncp->nc_nlen, nip);
2455 
2456 	/*
2457 	 * Finish up.
2458 	 */
2459 	if (error) {
2460 		hammer_rel_inode(nip, 0);
2461 		*ap->a_vpp = NULL;
2462 	} else {
2463 		error = hammer_get_vnode(nip, ap->a_vpp);
2464 		hammer_rel_inode(nip, 0);
2465 		if (error == 0) {
2466 			cache_setunresolved(ap->a_nch);
2467 			cache_setvp(ap->a_nch, *ap->a_vpp);
2468 			hammer_knote(ap->a_dvp, NOTE_WRITE);
2469 		}
2470 	}
2471 	hammer_done_transaction(&trans);
2472 	lwkt_reltoken(&hmp->fs_token);
2473 	return (error);
2474 }
2475 
2476 /*
2477  * hammer_vop_nwhiteout { nch, dvp, cred, flags }
2478  */
2479 static
2480 int
2481 hammer_vop_nwhiteout(struct vop_nwhiteout_args *ap)
2482 {
2483 	struct hammer_transaction trans;
2484 	hammer_inode_t dip;
2485 	hammer_mount_t hmp;
2486 	int error;
2487 
2488 	dip = VTOI(ap->a_dvp);
2489 	hmp = dip->hmp;
2490 
2491 	if (hammer_nohistory(dip) == 0 &&
2492 	    (error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0) {
2493 		return (error);
2494 	}
2495 
2496 	lwkt_gettoken(&hmp->fs_token);
2497 	hammer_start_transaction(&trans, hmp);
2498 	++hammer_stats_file_iopsw;
2499 	error = hammer_dounlink(&trans, ap->a_nch, ap->a_dvp,
2500 				ap->a_cred, ap->a_flags, -1);
2501 	hammer_done_transaction(&trans);
2502 	lwkt_reltoken(&hmp->fs_token);
2503 
2504 	return (error);
2505 }
2506 
2507 /*
2508  * hammer_vop_ioctl { vp, command, data, fflag, cred }
2509  */
2510 static
2511 int
2512 hammer_vop_ioctl(struct vop_ioctl_args *ap)
2513 {
2514 	hammer_inode_t ip = ap->a_vp->v_data;
2515 	hammer_mount_t hmp = ip->hmp;
2516 	int error;
2517 
2518 	++hammer_stats_file_iopsr;
2519 	lwkt_gettoken(&hmp->fs_token);
2520 	error = hammer_ioctl(ip, ap->a_command, ap->a_data,
2521 			     ap->a_fflag, ap->a_cred);
2522 	lwkt_reltoken(&hmp->fs_token);
2523 	return (error);
2524 }
2525 
2526 static
2527 int
2528 hammer_vop_mountctl(struct vop_mountctl_args *ap)
2529 {
2530 	static const struct mountctl_opt extraopt[] = {
2531 		{ HMNT_NOHISTORY,	"nohistory" },
2532 		{ HMNT_MASTERID,	"master" },
2533 		{ HMNT_NOMIRROR,	"nomirror" },
2534 		{ 0, NULL}
2535 
2536 	};
2537 	hammer_mount_t hmp;
2538 	struct mount *mp;
2539 	int usedbytes;
2540 	int error;
2541 
2542 	error = 0;
2543 	usedbytes = 0;
2544 	mp = ap->a_head.a_ops->head.vv_mount;
2545 	KKASSERT(mp->mnt_data != NULL);
2546 	hmp = (hammer_mount_t)mp->mnt_data;
2547 
2548 	lwkt_gettoken(&hmp->fs_token);
2549 
2550 	switch(ap->a_op) {
2551 	case MOUNTCTL_SET_EXPORT:
2552 		if (ap->a_ctllen != sizeof(struct export_args))
2553 			error = EINVAL;
2554 		else
2555 			error = hammer_vfs_export(mp, ap->a_op,
2556 				      (const struct export_args *)ap->a_ctl);
2557 		break;
2558 	case MOUNTCTL_MOUNTFLAGS:
2559 		/*
2560 		 * Call standard mountctl VOP function
2561 		 * so we get user mount flags.
2562 		 */
2563 		error = vop_stdmountctl(ap);
2564 		if (error)
2565 			break;
2566 
2567 		usedbytes = *ap->a_res;
2568 
2569 		if (usedbytes > 0 && usedbytes < ap->a_buflen) {
2570 			usedbytes += vfs_flagstostr(hmp->hflags, extraopt,
2571 						    ap->a_buf,
2572 						    ap->a_buflen - usedbytes,
2573 						    &error);
2574 		}
2575 
2576 		*ap->a_res += usedbytes;
2577 		break;
2578 	default:
2579 		error = vop_stdmountctl(ap);
2580 		break;
2581 	}
2582 	lwkt_reltoken(&hmp->fs_token);
2583 	return(error);
2584 }
2585 
2586 /*
2587  * hammer_vop_strategy { vp, bio }
2588  *
2589  * Strategy call, used for regular file read & write only.  Note that the
2590  * bp may represent a cluster.
2591  *
2592  * To simplify operation and allow better optimizations in the future,
2593  * this code does not make any assumptions with regards to buffer alignment
2594  * or size.
2595  */
2596 static
2597 int
2598 hammer_vop_strategy(struct vop_strategy_args *ap)
2599 {
2600 	struct buf *bp;
2601 	int error;
2602 
2603 	bp = ap->a_bio->bio_buf;
2604 
2605 	switch(bp->b_cmd) {
2606 	case BUF_CMD_READ:
2607 		error = hammer_vop_strategy_read(ap);
2608 		break;
2609 	case BUF_CMD_WRITE:
2610 		error = hammer_vop_strategy_write(ap);
2611 		break;
2612 	default:
2613 		bp->b_error = error = EINVAL;
2614 		bp->b_flags |= B_ERROR;
2615 		biodone(ap->a_bio);
2616 		break;
2617 	}
2618 
2619 	/* hammer_dump_dedup_cache(((hammer_inode_t)ap->a_vp->v_data)->hmp); */
2620 
2621 	return (error);
2622 }
2623 
2624 /*
2625  * Read from a regular file.  Iterate the related records and fill in the
2626  * BIO/BUF.  Gaps are zero-filled.
2627  *
2628  * The support code in hammer_object.c should be used to deal with mixed
2629  * in-memory and on-disk records.
2630  *
2631  * NOTE: Can be called from the cluster code with an oversized buf.
2632  *
2633  * XXX atime update
2634  */
2635 static
2636 int
2637 hammer_vop_strategy_read(struct vop_strategy_args *ap)
2638 {
2639 	struct hammer_transaction trans;
2640 	hammer_inode_t ip;
2641 	hammer_inode_t dip;
2642 	hammer_mount_t hmp;
2643 	struct hammer_cursor cursor;
2644 	hammer_base_elm_t base;
2645 	hammer_off_t disk_offset;
2646 	struct bio *bio;
2647 	struct bio *nbio;
2648 	struct buf *bp;
2649 	int64_t rec_offset;
2650 	int64_t ran_end;
2651 	int64_t tmp64;
2652 	int error;
2653 	int boff;
2654 	int roff;
2655 	int n;
2656 	int isdedupable;
2657 
2658 	bio = ap->a_bio;
2659 	bp = bio->bio_buf;
2660 	ip = ap->a_vp->v_data;
2661 	hmp = ip->hmp;
2662 
2663 	/*
2664 	 * The zone-2 disk offset may have been set by the cluster code via
2665 	 * a BMAP operation, or else should be NOOFFSET.
2666 	 *
2667 	 * Checking the high bits for a match against zone-2 should suffice.
2668 	 *
2669 	 * In cases where a lot of data duplication is present it may be
2670 	 * more beneficial to drop through and doubule-buffer through the
2671 	 * device.
2672 	 */
2673 	nbio = push_bio(bio);
2674 	if (hammer_is_zone_large_data(nbio->bio_offset)) {
2675 		if (hammer_double_buffer == 0) {
2676 			lwkt_gettoken(&hmp->fs_token);
2677 			error = hammer_io_direct_read(hmp, nbio, NULL);
2678 			lwkt_reltoken(&hmp->fs_token);
2679 			return (error);
2680 		}
2681 
2682 		/*
2683 		 * Try to shortcut requests for double_buffer mode too.
2684 		 * Since this mode runs through the device buffer cache
2685 		 * only compatible buffer sizes (meaning those generated
2686 		 * by normal filesystem buffers) are legal.
2687 		 */
2688 		if (hammer_live_dedup == 0 && (bp->b_flags & B_PAGING) == 0) {
2689 			lwkt_gettoken(&hmp->fs_token);
2690 			error = hammer_io_indirect_read(hmp, nbio, NULL);
2691 			lwkt_reltoken(&hmp->fs_token);
2692 			return (error);
2693 		}
2694 	}
2695 
2696 	/*
2697 	 * Well, that sucked.  Do it the hard way.  If all the stars are
2698 	 * aligned we may still be able to issue a direct-read.
2699 	 */
2700 	lwkt_gettoken(&hmp->fs_token);
2701 	hammer_simple_transaction(&trans, hmp);
2702 	hammer_init_cursor(&trans, &cursor, &ip->cache[1], ip);
2703 
2704 	/*
2705 	 * Key range (begin and end inclusive) to scan.  Note that the key's
2706 	 * stored in the actual records represent BASE+LEN, not BASE.  The
2707 	 * first record containing bio_offset will have a key > bio_offset.
2708 	 */
2709 	cursor.key_beg.localization = ip->obj_localization |
2710 				      HAMMER_LOCALIZE_MISC;
2711 	cursor.key_beg.obj_id = ip->obj_id;
2712 	cursor.key_beg.create_tid = 0;
2713 	cursor.key_beg.delete_tid = 0;
2714 	cursor.key_beg.obj_type = 0;
2715 	cursor.key_beg.key = bio->bio_offset + 1;
2716 	cursor.asof = ip->obj_asof;
2717 	cursor.flags |= HAMMER_CURSOR_ASOF;
2718 
2719 	cursor.key_end = cursor.key_beg;
2720 	KKASSERT(ip->ino_data.obj_type == HAMMER_OBJTYPE_REGFILE);
2721 #if 0
2722 	if (ip->ino_data.obj_type == HAMMER_OBJTYPE_DBFILE) {
2723 		cursor.key_beg.rec_type = HAMMER_RECTYPE_DB;
2724 		cursor.key_end.rec_type = HAMMER_RECTYPE_DB;
2725 		cursor.key_end.key = HAMMER_MAX_KEY;
2726 	} else
2727 #endif
2728 	{
2729 		ran_end = bio->bio_offset + bp->b_bufsize;
2730 		cursor.key_beg.rec_type = HAMMER_RECTYPE_DATA;
2731 		cursor.key_end.rec_type = HAMMER_RECTYPE_DATA;
2732 		tmp64 = ran_end + MAXPHYS + 1;	/* work-around GCC-4 bug */
2733 		if (tmp64 < ran_end)
2734 			cursor.key_end.key = HAMMER_MAX_KEY;
2735 		else
2736 			cursor.key_end.key = ran_end + MAXPHYS + 1;
2737 	}
2738 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE;
2739 
2740 	/*
2741 	 * Set NOSWAPCACHE for cursor data extraction if double buffering
2742 	 * is disabled or (if the file is not marked cacheable via chflags
2743 	 * and vm.swapcache_use_chflags is enabled).
2744 	 */
2745 	if (hammer_double_buffer == 0 ||
2746 	    ((ap->a_vp->v_flag & VSWAPCACHE) == 0 &&
2747 	     vm_swapcache_use_chflags)) {
2748 		cursor.flags |= HAMMER_CURSOR_NOSWAPCACHE;
2749 	}
2750 
2751 	error = hammer_ip_first(&cursor);
2752 	boff = 0;
2753 
2754 	while (error == 0) {
2755 		/*
2756 		 * Get the base file offset of the record.  The key for
2757 		 * data records is (base + bytes) rather then (base).
2758 		 */
2759 		base = &cursor.leaf->base;
2760 		rec_offset = base->key - cursor.leaf->data_len;
2761 
2762 		/*
2763 		 * Calculate the gap, if any, and zero-fill it.
2764 		 *
2765 		 * n is the offset of the start of the record verses our
2766 		 * current seek offset in the bio.
2767 		 */
2768 		n = (int)(rec_offset - (bio->bio_offset + boff));
2769 		if (n > 0) {
2770 			if (n > bp->b_bufsize - boff)
2771 				n = bp->b_bufsize - boff;
2772 			bzero((char *)bp->b_data + boff, n);
2773 			boff += n;
2774 			n = 0;
2775 		}
2776 
2777 		/*
2778 		 * Calculate the data offset in the record and the number
2779 		 * of bytes we can copy.
2780 		 *
2781 		 * There are two degenerate cases.  First, boff may already
2782 		 * be at bp->b_bufsize.  Secondly, the data offset within
2783 		 * the record may exceed the record's size.
2784 		 */
2785 		roff = -n;
2786 		rec_offset += roff;
2787 		n = cursor.leaf->data_len - roff;
2788 		if (n <= 0) {
2789 			hdkprintf("bad n=%d roff=%d\n", n, roff);
2790 			n = 0;
2791 		} else if (n > bp->b_bufsize - boff) {
2792 			n = bp->b_bufsize - boff;
2793 		}
2794 
2795 		/*
2796 		 * Deal with cached truncations.  This cool bit of code
2797 		 * allows truncate()/ftruncate() to avoid having to sync
2798 		 * the file.
2799 		 *
2800 		 * If the frontend is truncated then all backend records are
2801 		 * subject to the frontend's truncation.
2802 		 *
2803 		 * If the backend is truncated then backend records on-disk
2804 		 * (but not in-memory) are subject to the backend's
2805 		 * truncation.  In-memory records owned by the backend
2806 		 * represent data written after the truncation point on the
2807 		 * backend and must not be truncated.
2808 		 *
2809 		 * Truncate operations deal with frontend buffer cache
2810 		 * buffers and frontend-owned in-memory records synchronously.
2811 		 */
2812 		if (ip->flags & HAMMER_INODE_TRUNCATED) {
2813 			if (hammer_cursor_ondisk(&cursor)/* ||
2814 			    cursor.iprec->flush_state == HAMMER_FST_FLUSH*/) {
2815 				if (ip->trunc_off <= rec_offset)
2816 					n = 0;
2817 				else if (ip->trunc_off < rec_offset + n)
2818 					n = (int)(ip->trunc_off - rec_offset);
2819 			}
2820 		}
2821 		if (ip->sync_flags & HAMMER_INODE_TRUNCATED) {
2822 			if (hammer_cursor_ondisk(&cursor)) {
2823 				if (ip->sync_trunc_off <= rec_offset)
2824 					n = 0;
2825 				else if (ip->sync_trunc_off < rec_offset + n)
2826 					n = (int)(ip->sync_trunc_off - rec_offset);
2827 			}
2828 		}
2829 
2830 		/*
2831 		 * Try to issue a direct read into our bio if possible,
2832 		 * otherwise resolve the element data into a hammer_buffer
2833 		 * and copy.
2834 		 *
2835 		 * The buffer on-disk should be zerod past any real
2836 		 * truncation point, but may not be for any synthesized
2837 		 * truncation point from above.
2838 		 *
2839 		 * NOTE: disk_offset is only valid if the cursor data is
2840 		 *	 on-disk.
2841 		 */
2842 		disk_offset = cursor.leaf->data_offset + roff;
2843 		isdedupable = (boff == 0 && n == bp->b_bufsize &&
2844 			       hammer_cursor_ondisk(&cursor) &&
2845 			       ((int)disk_offset & HAMMER_BUFMASK) == 0);
2846 
2847 		if (isdedupable && hammer_double_buffer == 0) {
2848 			/*
2849 			 * Direct read case
2850 			 */
2851 			KKASSERT(hammer_is_zone_large_data(disk_offset));
2852 			nbio->bio_offset = disk_offset;
2853 			error = hammer_io_direct_read(hmp, nbio, cursor.leaf);
2854 			if (hammer_live_dedup && error == 0)
2855 				hammer_dedup_cache_add(ip, cursor.leaf);
2856 			goto done;
2857 		} else if (isdedupable) {
2858 			/*
2859 			 * Async I/O case for reading from backing store
2860 			 * and copying the data to the filesystem buffer.
2861 			 * live-dedup has to verify the data anyway if it
2862 			 * gets a hit later so we can just add the entry
2863 			 * now.
2864 			 */
2865 			KKASSERT(hammer_is_zone_large_data(disk_offset));
2866 			nbio->bio_offset = disk_offset;
2867 			if (hammer_live_dedup)
2868 				hammer_dedup_cache_add(ip, cursor.leaf);
2869 			error = hammer_io_indirect_read(hmp, nbio, cursor.leaf);
2870 			goto done;
2871 		} else if (n) {
2872 			error = hammer_ip_resolve_data(&cursor);
2873 			if (error == 0) {
2874 				if (hammer_live_dedup && isdedupable)
2875 					hammer_dedup_cache_add(ip, cursor.leaf);
2876 				bcopy((char *)cursor.data + roff,
2877 				      (char *)bp->b_data + boff, n);
2878 			}
2879 		}
2880 		if (error)
2881 			break;
2882 
2883 		/*
2884 		 * We have to be sure that the only elements added to the
2885 		 * dedup cache are those which are already on-media.
2886 		 */
2887 		if (hammer_live_dedup && hammer_cursor_ondisk(&cursor))
2888 			hammer_dedup_cache_add(ip, cursor.leaf);
2889 
2890 		/*
2891 		 * Iterate until we have filled the request.
2892 		 */
2893 		boff += n;
2894 		if (boff == bp->b_bufsize)
2895 			break;
2896 		error = hammer_ip_next(&cursor);
2897 	}
2898 
2899 	/*
2900 	 * There may have been a gap after the last record
2901 	 */
2902 	if (error == ENOENT)
2903 		error = 0;
2904 	if (error == 0 && boff != bp->b_bufsize) {
2905 		KKASSERT(boff < bp->b_bufsize);
2906 		bzero((char *)bp->b_data + boff, bp->b_bufsize - boff);
2907 		/* boff = bp->b_bufsize; */
2908 	}
2909 
2910 	/*
2911 	 * Disallow swapcache operation on the vnode buffer if double
2912 	 * buffering is enabled, the swapcache will get the data via
2913 	 * the block device buffer.
2914 	 */
2915 	if (hammer_double_buffer)
2916 		bp->b_flags |= B_NOTMETA;
2917 
2918 	/*
2919 	 * Cleanup
2920 	 */
2921 	bp->b_resid = 0;
2922 	bp->b_error = error;
2923 	if (error)
2924 		bp->b_flags |= B_ERROR;
2925 	biodone(ap->a_bio);
2926 
2927 done:
2928 	/*
2929 	 * Cache the b-tree node for the last data read in cache[1].
2930 	 *
2931 	 * If we hit the file EOF then also cache the node in the
2932 	 * governing directory's cache[3], it will be used to initialize
2933 	 * the new inode's cache[1] for any inodes looked up via the directory.
2934 	 *
2935 	 * This doesn't reduce disk accesses since the B-Tree chain is
2936 	 * likely cached, but it does reduce cpu overhead when looking
2937 	 * up file offsets for cpdup/tar/cpio style iterations.
2938 	 */
2939 	if (cursor.node)
2940 		hammer_cache_node(&ip->cache[1], cursor.node);
2941 	if (ran_end >= ip->ino_data.size) {
2942 		dip = hammer_find_inode(&trans, ip->ino_data.parent_obj_id,
2943 					ip->obj_asof, ip->obj_localization);
2944 		if (dip) {
2945 			hammer_cache_node(&dip->cache[3], cursor.node);
2946 			hammer_rel_inode(dip, 0);
2947 		}
2948 	}
2949 	hammer_done_cursor(&cursor);
2950 	hammer_done_transaction(&trans);
2951 	lwkt_reltoken(&hmp->fs_token);
2952 	return(error);
2953 }
2954 
2955 /*
2956  * BMAP operation - used to support cluster_read() only.
2957  *
2958  * (struct vnode *vp, off_t loffset, off_t *doffsetp, int *runp, int *runb)
2959  *
2960  * This routine may return EOPNOTSUPP if the opration is not supported for
2961  * the specified offset.  The contents of the pointer arguments do not
2962  * need to be initialized in that case.
2963  *
2964  * If a disk address is available and properly aligned return 0 with
2965  * *doffsetp set to the zone-2 address, and *runp / *runb set appropriately
2966  * to the run-length relative to that offset.  Callers may assume that
2967  * *doffsetp is valid if 0 is returned, even if *runp is not sufficiently
2968  * large, so return EOPNOTSUPP if it is not sufficiently large.
2969  */
2970 static
2971 int
2972 hammer_vop_bmap(struct vop_bmap_args *ap)
2973 {
2974 	struct hammer_transaction trans;
2975 	hammer_inode_t ip;
2976 	hammer_mount_t hmp;
2977 	struct hammer_cursor cursor;
2978 	hammer_base_elm_t base;
2979 	int64_t rec_offset;
2980 	int64_t ran_end;
2981 	int64_t tmp64;
2982 	int64_t base_offset;
2983 	int64_t base_disk_offset;
2984 	int64_t last_offset;
2985 	hammer_off_t last_disk_offset;
2986 	hammer_off_t disk_offset;
2987 	int	rec_len;
2988 	int	error;
2989 	int	blksize;
2990 
2991 	++hammer_stats_file_iopsr;
2992 	ip = ap->a_vp->v_data;
2993 	hmp = ip->hmp;
2994 
2995 	/*
2996 	 * We can only BMAP regular files.  We can't BMAP database files,
2997 	 * directories, etc.
2998 	 */
2999 	if (ip->ino_data.obj_type != HAMMER_OBJTYPE_REGFILE)
3000 		return(EOPNOTSUPP);
3001 
3002 	/*
3003 	 * bmap is typically called with runp/runb both NULL when used
3004 	 * for writing.  We do not support BMAP for writing atm.
3005 	 */
3006 	if (ap->a_cmd != BUF_CMD_READ)
3007 		return(EOPNOTSUPP);
3008 
3009 	/*
3010 	 * Scan the B-Tree to acquire blockmap addresses, then translate
3011 	 * to raw addresses.
3012 	 */
3013 	lwkt_gettoken(&hmp->fs_token);
3014 	hammer_simple_transaction(&trans, hmp);
3015 
3016 	hammer_init_cursor(&trans, &cursor, &ip->cache[1], ip);
3017 
3018 	/*
3019 	 * Key range (begin and end inclusive) to scan.  Note that the key's
3020 	 * stored in the actual records represent BASE+LEN, not BASE.  The
3021 	 * first record containing bio_offset will have a key > bio_offset.
3022 	 */
3023 	cursor.key_beg.localization = ip->obj_localization |
3024 				      HAMMER_LOCALIZE_MISC;
3025 	cursor.key_beg.obj_id = ip->obj_id;
3026 	cursor.key_beg.create_tid = 0;
3027 	cursor.key_beg.delete_tid = 0;
3028 	cursor.key_beg.obj_type = 0;
3029 	if (ap->a_runb)
3030 		cursor.key_beg.key = ap->a_loffset - MAXPHYS + 1;
3031 	else
3032 		cursor.key_beg.key = ap->a_loffset + 1;
3033 	if (cursor.key_beg.key < 0)
3034 		cursor.key_beg.key = 0;
3035 	cursor.asof = ip->obj_asof;
3036 	cursor.flags |= HAMMER_CURSOR_ASOF;
3037 
3038 	cursor.key_end = cursor.key_beg;
3039 	KKASSERT(ip->ino_data.obj_type == HAMMER_OBJTYPE_REGFILE);
3040 
3041 	ran_end = ap->a_loffset + MAXPHYS;
3042 	cursor.key_beg.rec_type = HAMMER_RECTYPE_DATA;
3043 	cursor.key_end.rec_type = HAMMER_RECTYPE_DATA;
3044 	tmp64 = ran_end + MAXPHYS + 1;	/* work-around GCC-4 bug */
3045 	if (tmp64 < ran_end)
3046 		cursor.key_end.key = HAMMER_MAX_KEY;
3047 	else
3048 		cursor.key_end.key = ran_end + MAXPHYS + 1;
3049 
3050 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE;
3051 
3052 	error = hammer_ip_first(&cursor);
3053 	base_offset = last_offset = 0;
3054 	base_disk_offset = last_disk_offset = 0;
3055 
3056 	while (error == 0) {
3057 		/*
3058 		 * Get the base file offset of the record.  The key for
3059 		 * data records is (base + bytes) rather then (base).
3060 		 *
3061 		 * NOTE: rec_offset + rec_len may exceed the end-of-file.
3062 		 * The extra bytes should be zero on-disk and the BMAP op
3063 		 * should still be ok.
3064 		 */
3065 		base = &cursor.leaf->base;
3066 		rec_offset = base->key - cursor.leaf->data_len;
3067 		rec_len    = cursor.leaf->data_len;
3068 
3069 		/*
3070 		 * Incorporate any cached truncation.
3071 		 *
3072 		 * NOTE: Modifications to rec_len based on synthesized
3073 		 * truncation points remove the guarantee that any extended
3074 		 * data on disk is zero (since the truncations may not have
3075 		 * taken place on-media yet).
3076 		 */
3077 		if (ip->flags & HAMMER_INODE_TRUNCATED) {
3078 			if (hammer_cursor_ondisk(&cursor) ||
3079 			    cursor.iprec->flush_state == HAMMER_FST_FLUSH) {
3080 				if (ip->trunc_off <= rec_offset)
3081 					rec_len = 0;
3082 				else if (ip->trunc_off < rec_offset + rec_len)
3083 					rec_len = (int)(ip->trunc_off - rec_offset);
3084 			}
3085 		}
3086 		if (ip->sync_flags & HAMMER_INODE_TRUNCATED) {
3087 			if (hammer_cursor_ondisk(&cursor)) {
3088 				if (ip->sync_trunc_off <= rec_offset)
3089 					rec_len = 0;
3090 				else if (ip->sync_trunc_off < rec_offset + rec_len)
3091 					rec_len = (int)(ip->sync_trunc_off - rec_offset);
3092 			}
3093 		}
3094 
3095 		/*
3096 		 * Accumulate information.  If we have hit a discontiguous
3097 		 * block reset base_offset unless we are already beyond the
3098 		 * requested offset.  If we are, that's it, we stop.
3099 		 */
3100 		if (error)
3101 			break;
3102 		if (hammer_cursor_ondisk(&cursor)) {
3103 			disk_offset = cursor.leaf->data_offset;
3104 			if (rec_offset != last_offset ||
3105 			    disk_offset != last_disk_offset) {
3106 				if (rec_offset > ap->a_loffset)
3107 					break;
3108 				base_offset = rec_offset;
3109 				base_disk_offset = disk_offset;
3110 			}
3111 			last_offset = rec_offset + rec_len;
3112 			last_disk_offset = disk_offset + rec_len;
3113 
3114 			if (hammer_live_dedup)
3115 				hammer_dedup_cache_add(ip, cursor.leaf);
3116 		}
3117 
3118 		error = hammer_ip_next(&cursor);
3119 	}
3120 
3121 	if (cursor.node)
3122 		hammer_cache_node(&ip->cache[1], cursor.node);
3123 
3124 	hammer_done_cursor(&cursor);
3125 	hammer_done_transaction(&trans);
3126 	lwkt_reltoken(&hmp->fs_token);
3127 
3128 	/*
3129 	 * If we couldn't find any records or the records we did find were
3130 	 * all behind the requested offset, return failure.  A forward
3131 	 * truncation can leave a hole w/ no on-disk records.
3132 	 */
3133 	if (last_offset == 0 || last_offset < ap->a_loffset)
3134 		return (EOPNOTSUPP);
3135 
3136 	/*
3137 	 * Figure out the block size at the requested offset and adjust
3138 	 * our limits so the cluster_read() does not create inappropriately
3139 	 * sized buffer cache buffers.
3140 	 */
3141 	blksize = hammer_blocksize(ap->a_loffset);
3142 	if (hammer_blocksize(base_offset) != blksize) {
3143 		base_offset = hammer_blockdemarc(base_offset, ap->a_loffset);
3144 	}
3145 	if (last_offset != ap->a_loffset &&
3146 	    hammer_blocksize(last_offset - 1) != blksize) {
3147 		last_offset = hammer_blockdemarc(ap->a_loffset,
3148 						 last_offset - 1);
3149 	}
3150 
3151 	/*
3152 	 * Returning EOPNOTSUPP simply prevents the direct-IO optimization
3153 	 * from occuring.
3154 	 */
3155 	disk_offset = base_disk_offset + (ap->a_loffset - base_offset);
3156 
3157 	if (!hammer_is_zone_large_data(disk_offset)) {
3158 		/*
3159 		 * Only large-data zones can be direct-IOd
3160 		 */
3161 		error = EOPNOTSUPP;
3162 	} else if ((disk_offset & HAMMER_BUFMASK) ||
3163 		   (last_offset - ap->a_loffset) < blksize) {
3164 		/*
3165 		 * doffsetp is not aligned or the forward run size does
3166 		 * not cover a whole buffer, disallow the direct I/O.
3167 		 */
3168 		error = EOPNOTSUPP;
3169 	} else {
3170 		/*
3171 		 * We're good.
3172 		 */
3173 		*ap->a_doffsetp = disk_offset;
3174 		if (ap->a_runb) {
3175 			*ap->a_runb = ap->a_loffset - base_offset;
3176 			KKASSERT(*ap->a_runb >= 0);
3177 		}
3178 		if (ap->a_runp) {
3179 			*ap->a_runp = last_offset - ap->a_loffset;
3180 			KKASSERT(*ap->a_runp >= 0);
3181 		}
3182 		error = 0;
3183 	}
3184 	return(error);
3185 }
3186 
3187 /*
3188  * Write to a regular file.   Because this is a strategy call the OS is
3189  * trying to actually get data onto the media.
3190  */
3191 static
3192 int
3193 hammer_vop_strategy_write(struct vop_strategy_args *ap)
3194 {
3195 	hammer_record_t record;
3196 	hammer_mount_t hmp;
3197 	hammer_inode_t ip;
3198 	struct bio *bio;
3199 	struct buf *bp;
3200 	int blksize __debugvar;
3201 	int bytes;
3202 	int error;
3203 
3204 	bio = ap->a_bio;
3205 	bp = bio->bio_buf;
3206 	ip = ap->a_vp->v_data;
3207 	hmp = ip->hmp;
3208 
3209 	blksize = hammer_blocksize(bio->bio_offset);
3210 	KKASSERT(bp->b_bufsize == blksize);
3211 
3212 	if (ip->flags & HAMMER_INODE_RO) {
3213 		bp->b_error = EROFS;
3214 		bp->b_flags |= B_ERROR;
3215 		biodone(ap->a_bio);
3216 		return(EROFS);
3217 	}
3218 
3219 	lwkt_gettoken(&hmp->fs_token);
3220 
3221 	/*
3222 	 * Disallow swapcache operation on the vnode buffer if double
3223 	 * buffering is enabled, the swapcache will get the data via
3224 	 * the block device buffer.
3225 	 */
3226 	if (hammer_double_buffer)
3227 		bp->b_flags |= B_NOTMETA;
3228 
3229 	/*
3230 	 * Interlock with inode destruction (no in-kernel or directory
3231 	 * topology visibility).  If we queue new IO while trying to
3232 	 * destroy the inode we can deadlock the vtrunc call in
3233 	 * hammer_inode_unloadable_check().
3234 	 *
3235 	 * Besides, there's no point flushing a bp associated with an
3236 	 * inode that is being destroyed on-media and has no kernel
3237 	 * references.
3238 	 */
3239 	if ((ip->flags | ip->sync_flags) &
3240 	    (HAMMER_INODE_DELETING|HAMMER_INODE_DELETED)) {
3241 		bp->b_resid = 0;
3242 		biodone(ap->a_bio);
3243 		lwkt_reltoken(&hmp->fs_token);
3244 		return(0);
3245 	}
3246 
3247 	/*
3248 	 * Reserve space and issue a direct-write from the front-end.
3249 	 * NOTE: The direct_io code will hammer_bread/bcopy smaller
3250 	 * allocations.
3251 	 *
3252 	 * An in-memory record will be installed to reference the storage
3253 	 * until the flusher can get to it.
3254 	 *
3255 	 * Since we own the high level bio the front-end will not try to
3256 	 * do a direct-read until the write completes.
3257 	 *
3258 	 * NOTE: The only time we do not reserve a full-sized buffers
3259 	 * worth of data is if the file is small.  We do not try to
3260 	 * allocate a fragment (from the small-data zone) at the end of
3261 	 * an otherwise large file as this can lead to wildly separated
3262 	 * data.
3263 	 */
3264 	KKASSERT((bio->bio_offset & HAMMER_BUFMASK) == 0);
3265 	KKASSERT(bio->bio_offset < ip->ino_data.size);
3266 	if (bio->bio_offset || ip->ino_data.size > HAMMER_HBUFSIZE)
3267 		bytes = bp->b_bufsize;
3268 	else
3269 		bytes = HAMMER_DATA_DOALIGN_WITH(int, ip->ino_data.size);
3270 
3271 	record = hammer_ip_add_bulk(ip, bio->bio_offset, bp->b_data,
3272 				    bytes, &error);
3273 
3274 	/*
3275 	 * B_VFSFLAG1 indicates that a REDO_WRITE entry was generated
3276 	 * in hammer_vop_write().  We must flag the record so the proper
3277 	 * REDO_TERM_WRITE entry is generated during the flush.
3278 	 */
3279 	if (record) {
3280 		if (bp->b_flags & B_VFSFLAG1) {
3281 			record->flags |= HAMMER_RECF_REDO;
3282 			bp->b_flags &= ~B_VFSFLAG1;
3283 		}
3284 		if (record->flags & HAMMER_RECF_DEDUPED) {
3285 			bp->b_resid = 0;
3286 			hammer_ip_replace_bulk(hmp, record);
3287 			biodone(ap->a_bio);
3288 		} else {
3289 			hammer_io_direct_write(hmp, bio, record);
3290 		}
3291 		if (ip->rsv_recs > 1 && hmp->rsv_recs > hammer_limit_recs)
3292 			hammer_flush_inode(ip, 0);
3293 	} else {
3294 		bp->b_bio2.bio_offset = NOOFFSET;
3295 		bp->b_error = error;
3296 		bp->b_flags |= B_ERROR;
3297 		biodone(ap->a_bio);
3298 	}
3299 	lwkt_reltoken(&hmp->fs_token);
3300 	return(error);
3301 }
3302 
3303 /*
3304  * dounlink - disconnect a directory entry
3305  *
3306  * XXX whiteout support not really in yet
3307  */
3308 static int
3309 hammer_dounlink(hammer_transaction_t trans, struct nchandle *nch,
3310 		struct vnode *dvp, struct ucred *cred,
3311 		int flags, int isdir)
3312 {
3313 	struct namecache *ncp;
3314 	hammer_inode_t dip;
3315 	hammer_inode_t ip;
3316 	hammer_mount_t hmp;
3317 	struct hammer_cursor cursor;
3318 	int64_t namekey;
3319 	uint32_t max_iterations;
3320 	int nlen, error;
3321 
3322 	/*
3323 	 * Calculate the namekey and setup the key range for the scan.  This
3324 	 * works kinda like a chained hash table where the lower 32 bits
3325 	 * of the namekey synthesize the chain.
3326 	 *
3327 	 * The key range is inclusive of both key_beg and key_end.
3328 	 */
3329 	dip = VTOI(dvp);
3330 	ncp = nch->ncp;
3331 	hmp = dip->hmp;
3332 
3333 	if (dip->flags & HAMMER_INODE_RO)
3334 		return (EROFS);
3335 
3336 	namekey = hammer_direntry_namekey(dip, ncp->nc_name, ncp->nc_nlen,
3337 					   &max_iterations);
3338 retry:
3339 	hammer_init_cursor(trans, &cursor, &dip->cache[1], dip);
3340 	cursor.key_beg.localization = dip->obj_localization |
3341 				      hammer_dir_localization(dip);
3342         cursor.key_beg.obj_id = dip->obj_id;
3343 	cursor.key_beg.key = namekey;
3344         cursor.key_beg.create_tid = 0;
3345         cursor.key_beg.delete_tid = 0;
3346         cursor.key_beg.rec_type = HAMMER_RECTYPE_DIRENTRY;
3347         cursor.key_beg.obj_type = 0;
3348 
3349 	cursor.key_end = cursor.key_beg;
3350 	cursor.key_end.key += max_iterations;
3351 	cursor.asof = dip->obj_asof;
3352 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF;
3353 
3354 	/*
3355 	 * Scan all matching records (the chain), locate the one matching
3356 	 * the requested path component.  info->last_error contains the
3357 	 * error code on search termination and could be 0, ENOENT, or
3358 	 * something else.
3359 	 *
3360 	 * The hammer_ip_*() functions merge in-memory records with on-disk
3361 	 * records for the purposes of the search.
3362 	 */
3363 	error = hammer_ip_first(&cursor);
3364 
3365 	while (error == 0) {
3366 		error = hammer_ip_resolve_data(&cursor);
3367 		if (error)
3368 			break;
3369 		nlen = cursor.leaf->data_len - HAMMER_ENTRY_NAME_OFF;
3370 		KKASSERT(nlen > 0);
3371 		if (ncp->nc_nlen == nlen &&
3372 		    bcmp(ncp->nc_name, cursor.data->entry.name, nlen) == 0) {
3373 			break;
3374 		}
3375 		error = hammer_ip_next(&cursor);
3376 	}
3377 
3378 	/*
3379 	 * If all is ok we have to get the inode so we can adjust nlinks.
3380 	 * To avoid a deadlock with the flusher we must release the inode
3381 	 * lock on the directory when acquiring the inode for the entry.
3382 	 *
3383 	 * If the target is a directory, it must be empty.
3384 	 */
3385 	if (error == 0) {
3386 		hammer_unlock(&cursor.ip->lock);
3387 		ip = hammer_get_inode(trans, dip, cursor.data->entry.obj_id,
3388 				      hmp->asof,
3389 				      cursor.data->entry.localization,
3390 				      0, &error);
3391 		hammer_lock_sh(&cursor.ip->lock);
3392 		if (error == ENOENT) {
3393 			hkprintf("WARNING: Removing dirent w/missing inode "
3394 				"\"%s\"\n"
3395 				"\tobj_id = %016jx\n",
3396 				ncp->nc_name,
3397 				(intmax_t)cursor.data->entry.obj_id);
3398 			error = 0;
3399 		}
3400 
3401 		/*
3402 		 * If isdir >= 0 we validate that the entry is or is not a
3403 		 * directory.  If isdir < 0 we don't care.
3404 		 */
3405 		if (error == 0 && isdir >= 0 && ip) {
3406 			if (isdir &&
3407 			    ip->ino_data.obj_type != HAMMER_OBJTYPE_DIRECTORY) {
3408 				error = ENOTDIR;
3409 			} else if (isdir == 0 &&
3410 			    ip->ino_data.obj_type == HAMMER_OBJTYPE_DIRECTORY) {
3411 				error = EISDIR;
3412 			}
3413 		}
3414 
3415 		/*
3416 		 * If we are trying to remove a directory the directory must
3417 		 * be empty.
3418 		 *
3419 		 * The check directory code can loop and deadlock/retry.  Our
3420 		 * own cursor's node locks must be released to avoid a 3-way
3421 		 * deadlock with the flusher if the check directory code
3422 		 * blocks.
3423 		 *
3424 		 * If any changes whatsoever have been made to the cursor
3425 		 * set EDEADLK and retry.
3426 		 *
3427 		 * WARNING: See warnings in hammer_unlock_cursor()
3428 		 *	    function.
3429 		 */
3430 		if (error == 0 && ip && ip->ino_data.obj_type ==
3431 				        HAMMER_OBJTYPE_DIRECTORY) {
3432 			hammer_unlock_cursor(&cursor);
3433 			error = hammer_ip_check_directory_empty(trans, ip);
3434 			hammer_lock_cursor(&cursor);
3435 			if (cursor.flags & HAMMER_CURSOR_RETEST) {
3436 				hkprintf("Warning: avoided deadlock "
3437 					"on rmdir '%s'\n",
3438 					ncp->nc_name);
3439 				error = EDEADLK;
3440 			}
3441 		}
3442 
3443 		/*
3444 		 * Delete the directory entry.
3445 		 *
3446 		 * WARNING: hammer_ip_del_direntry() may have to terminate
3447 		 * the cursor to avoid a deadlock.  It is ok to call
3448 		 * hammer_done_cursor() twice.
3449 		 */
3450 		if (error == 0) {
3451 			error = hammer_ip_del_direntry(trans, &cursor,
3452 							dip, ip);
3453 		}
3454 		hammer_done_cursor(&cursor);
3455 		if (error == 0) {
3456 			/*
3457 			 * Tell the namecache that we are now unlinked.
3458 			 */
3459 			cache_unlink(nch);
3460 
3461 			/*
3462 			 * NOTE: ip->vp, if non-NULL, cannot be directly
3463 			 *	 referenced without formally acquiring the
3464 			 *	 vp since the vp might have zero refs on it,
3465 			 *	 or in the middle of a reclaim, etc.
3466 			 *
3467 			 * NOTE: The cache_setunresolved() can rip the vp
3468 			 *	 out from under us since the vp may not have
3469 			 *	 any refs, in which case ip->vp will be NULL
3470 			 *	 from the outset.
3471 			 */
3472 			while (ip && ip->vp) {
3473 				struct vnode *vp;
3474 
3475 				error = hammer_get_vnode(ip, &vp);
3476 				if (error == 0 && vp) {
3477 					vn_unlock(vp);
3478 					hammer_knote(ip->vp, NOTE_DELETE);
3479 #if 0
3480 					/*
3481 					 * Don't do this, it can deadlock
3482 					 * on concurrent rm's of hardlinks.
3483 					 * Shouldn't be needed any more.
3484 					 */
3485 					cache_inval_vp(ip->vp, CINV_DESTROY);
3486 #endif
3487 					vrele(vp);
3488 					break;
3489 				}
3490 				hdkprintf("ip/vp race1 avoided\n");
3491 			}
3492 		}
3493 		if (ip)
3494 			hammer_rel_inode(ip, 0);
3495 	} else {
3496 		hammer_done_cursor(&cursor);
3497 	}
3498 	if (error == EDEADLK)
3499 		goto retry;
3500 
3501 	return (error);
3502 }
3503 
3504 /************************************************************************
3505  *			    FIFO AND SPECFS OPS				*
3506  ************************************************************************
3507  *
3508  */
3509 static int
3510 hammer_vop_fifoclose (struct vop_close_args *ap)
3511 {
3512 	/* XXX update itimes */
3513 	return (VOCALL(&fifo_vnode_vops, &ap->a_head));
3514 }
3515 
3516 static int
3517 hammer_vop_fiforead (struct vop_read_args *ap)
3518 {
3519 	int error;
3520 
3521 	error = VOCALL(&fifo_vnode_vops, &ap->a_head);
3522 	/* XXX update access time */
3523 	return (error);
3524 }
3525 
3526 static int
3527 hammer_vop_fifowrite (struct vop_write_args *ap)
3528 {
3529 	int error;
3530 
3531 	error = VOCALL(&fifo_vnode_vops, &ap->a_head);
3532 	/* XXX update access time */
3533 	return (error);
3534 }
3535 
3536 static
3537 int
3538 hammer_vop_fifokqfilter(struct vop_kqfilter_args *ap)
3539 {
3540 	int error;
3541 
3542 	error = VOCALL(&fifo_vnode_vops, &ap->a_head);
3543 	if (error)
3544 		error = hammer_vop_kqfilter(ap);
3545 	return(error);
3546 }
3547 
3548 /************************************************************************
3549  *			    KQFILTER OPS				*
3550  ************************************************************************
3551  *
3552  */
3553 static void filt_hammerdetach(struct knote *kn);
3554 static int filt_hammerread(struct knote *kn, long hint);
3555 static int filt_hammerwrite(struct knote *kn, long hint);
3556 static int filt_hammervnode(struct knote *kn, long hint);
3557 
3558 static struct filterops hammerread_filtops =
3559 	{ FILTEROP_ISFD | FILTEROP_MPSAFE,
3560 	  NULL, filt_hammerdetach, filt_hammerread };
3561 static struct filterops hammerwrite_filtops =
3562 	{ FILTEROP_ISFD | FILTEROP_MPSAFE,
3563 	  NULL, filt_hammerdetach, filt_hammerwrite };
3564 static struct filterops hammervnode_filtops =
3565 	{ FILTEROP_ISFD | FILTEROP_MPSAFE,
3566 	  NULL, filt_hammerdetach, filt_hammervnode };
3567 
3568 static
3569 int
3570 hammer_vop_kqfilter(struct vop_kqfilter_args *ap)
3571 {
3572 	struct vnode *vp = ap->a_vp;
3573 	struct knote *kn = ap->a_kn;
3574 
3575 	switch (kn->kn_filter) {
3576 	case EVFILT_READ:
3577 		kn->kn_fop = &hammerread_filtops;
3578 		break;
3579 	case EVFILT_WRITE:
3580 		kn->kn_fop = &hammerwrite_filtops;
3581 		break;
3582 	case EVFILT_VNODE:
3583 		kn->kn_fop = &hammervnode_filtops;
3584 		break;
3585 	default:
3586 		return (EOPNOTSUPP);
3587 	}
3588 
3589 	kn->kn_hook = (caddr_t)vp;
3590 
3591 	knote_insert(&vp->v_pollinfo.vpi_kqinfo.ki_note, kn);
3592 
3593 	return(0);
3594 }
3595 
3596 static void
3597 filt_hammerdetach(struct knote *kn)
3598 {
3599 	struct vnode *vp = (void *)kn->kn_hook;
3600 
3601 	knote_remove(&vp->v_pollinfo.vpi_kqinfo.ki_note, kn);
3602 }
3603 
3604 static int
3605 filt_hammerread(struct knote *kn, long hint)
3606 {
3607 	struct vnode *vp = (void *)kn->kn_hook;
3608 	hammer_inode_t ip = VTOI(vp);
3609 	hammer_mount_t hmp = ip->hmp;
3610 	off_t off;
3611 
3612 	if (hint == NOTE_REVOKE) {
3613 		kn->kn_flags |= (EV_EOF | EV_NODATA | EV_ONESHOT);
3614 		return(1);
3615 	}
3616 	lwkt_gettoken(&hmp->fs_token);	/* XXX use per-ip-token */
3617 	off = ip->ino_data.size - kn->kn_fp->f_offset;
3618 	kn->kn_data = (off < INTPTR_MAX) ? off : INTPTR_MAX;
3619 	lwkt_reltoken(&hmp->fs_token);
3620 	if (kn->kn_sfflags & NOTE_OLDAPI)
3621 		return(1);
3622 	return (kn->kn_data != 0);
3623 }
3624 
3625 static int
3626 filt_hammerwrite(struct knote *kn, long hint)
3627 {
3628 	if (hint == NOTE_REVOKE)
3629 		kn->kn_flags |= (EV_EOF | EV_NODATA | EV_ONESHOT);
3630 	kn->kn_data = 0;
3631 	return (1);
3632 }
3633 
3634 static int
3635 filt_hammervnode(struct knote *kn, long hint)
3636 {
3637 	if (kn->kn_sfflags & hint)
3638 		kn->kn_fflags |= hint;
3639 	if (hint == NOTE_REVOKE) {
3640 		kn->kn_flags |= (EV_EOF | EV_NODATA);
3641 		return (1);
3642 	}
3643 	return (kn->kn_fflags != 0);
3644 }
3645 
3646