xref: /dragonfly/sys/vfs/hammer/hammer_vnops.c (revision 59b0b316)
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 	uid = hammer_to_unix_xid(&ip->ino_data.uid);
845 	gid = hammer_to_unix_xid(&ip->ino_data.gid);
846 
847 	error = vop_helper_access(ap, uid, gid, ip->ino_data.mode,
848 				  ip->ino_data.uflags);
849 	return (error);
850 }
851 
852 /*
853  * hammer_vop_advlock { vp, id, op, fl, flags }
854  *
855  * MPSAFE - does not require fs_token
856  */
857 static
858 int
859 hammer_vop_advlock(struct vop_advlock_args *ap)
860 {
861 	hammer_inode_t ip = VTOI(ap->a_vp);
862 
863 	return (lf_advlock(ap, &ip->advlock, ip->ino_data.size));
864 }
865 
866 /*
867  * hammer_vop_close { vp, fflag }
868  *
869  * We can only sync-on-close for normal closes.  XXX disabled for now.
870  */
871 static
872 int
873 hammer_vop_close(struct vop_close_args *ap)
874 {
875 #if 0
876 	struct vnode *vp = ap->a_vp;
877 	hammer_inode_t ip = VTOI(vp);
878 	int waitfor;
879 	if (ip->flags & (HAMMER_INODE_CLOSESYNC|HAMMER_INODE_CLOSEASYNC)) {
880 		if (vn_islocked(vp) == LK_EXCLUSIVE &&
881 		    (vp->v_flag & (VINACTIVE|VRECLAIMED)) == 0) {
882 			if (ip->flags & HAMMER_INODE_CLOSESYNC)
883 				waitfor = MNT_WAIT;
884 			else
885 				waitfor = MNT_NOWAIT;
886 			ip->flags &= ~(HAMMER_INODE_CLOSESYNC |
887 				       HAMMER_INODE_CLOSEASYNC);
888 			VOP_FSYNC(vp, MNT_NOWAIT, waitfor);
889 		}
890 	}
891 #endif
892 	return (vop_stdclose(ap));
893 }
894 
895 /*
896  * hammer_vop_ncreate { nch, dvp, vpp, cred, vap }
897  *
898  * The operating system has already ensured that the directory entry
899  * does not exist and done all appropriate namespace locking.
900  */
901 static
902 int
903 hammer_vop_ncreate(struct vop_ncreate_args *ap)
904 {
905 	struct hammer_transaction trans;
906 	hammer_inode_t dip;
907 	hammer_inode_t nip;
908 	struct nchandle *nch;
909 	hammer_mount_t hmp;
910 	int error;
911 
912 	nch = ap->a_nch;
913 	dip = VTOI(ap->a_dvp);
914 	hmp = dip->hmp;
915 
916 	if (dip->flags & HAMMER_INODE_RO)
917 		return (EROFS);
918 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
919 		return (error);
920 
921 	/*
922 	 * Create a transaction to cover the operations we perform.
923 	 */
924 	lwkt_gettoken(&hmp->fs_token);
925 	hammer_start_transaction(&trans, hmp);
926 
927 	/*
928 	 * Create a new filesystem object of the requested type.  The
929 	 * returned inode will be referenced and shared-locked to prevent
930 	 * it from being moved to the flusher.
931 	 */
932 	error = hammer_create_inode(&trans, ap->a_vap, ap->a_cred,
933 				    dip, nch->ncp->nc_name, nch->ncp->nc_nlen,
934 				    NULL, &nip);
935 	if (error) {
936 		hkprintf("hammer_create_inode error %d\n", error);
937 		hammer_done_transaction(&trans);
938 		*ap->a_vpp = NULL;
939 		lwkt_reltoken(&hmp->fs_token);
940 		return (error);
941 	}
942 
943 	/*
944 	 * Add the new filesystem object to the directory.  This will also
945 	 * bump the inode's link count.
946 	 */
947 	error = hammer_ip_add_direntry(&trans, dip,
948 					nch->ncp->nc_name, nch->ncp->nc_nlen,
949 					nip);
950 	if (error)
951 		hkprintf("hammer_ip_add_direntry error %d\n", error);
952 
953 	/*
954 	 * Finish up.
955 	 */
956 	if (error) {
957 		hammer_rel_inode(nip, 0);
958 		hammer_done_transaction(&trans);
959 		*ap->a_vpp = NULL;
960 	} else {
961 		error = hammer_get_vnode(nip, ap->a_vpp);
962 		hammer_done_transaction(&trans);
963 		hammer_rel_inode(nip, 0);
964 		if (error == 0) {
965 			cache_setunresolved(ap->a_nch);
966 			cache_setvp(ap->a_nch, *ap->a_vpp);
967 		}
968 		hammer_knote(ap->a_dvp, NOTE_WRITE);
969 	}
970 	lwkt_reltoken(&hmp->fs_token);
971 	return (error);
972 }
973 
974 /*
975  * hammer_vop_getattr { vp, vap }
976  *
977  * Retrieve an inode's attribute information.  When accessing inodes
978  * historically we fake the atime field to ensure consistent results.
979  * The atime field is stored in the B-Tree element and allowed to be
980  * updated without cycling the element.
981  *
982  * MPSAFE - does not require fs_token
983  */
984 static
985 int
986 hammer_vop_getattr(struct vop_getattr_args *ap)
987 {
988 	hammer_inode_t ip = VTOI(ap->a_vp);
989 	struct vattr *vap = ap->a_vap;
990 
991 	/*
992 	 * We want the fsid to be different when accessing a filesystem
993 	 * with different as-of's so programs like diff don't think
994 	 * the files are the same.
995 	 *
996 	 * We also want the fsid to be the same when comparing snapshots,
997 	 * or when comparing mirrors (which might be backed by different
998 	 * physical devices).  HAMMER fsids are based on the PFS's
999 	 * shared_uuid field.
1000 	 *
1001 	 * XXX there is a chance of collision here.  The va_fsid reported
1002 	 * by stat is different from the more involved fsid used in the
1003 	 * mount structure.
1004 	 */
1005 	hammer_lock_sh(&ip->lock);
1006 	vap->va_fsid = ip->pfsm->fsid_udev ^ (uint32_t)ip->obj_asof ^
1007 		       (uint32_t)(ip->obj_asof >> 32);
1008 
1009 	vap->va_fileid = ip->ino_leaf.base.obj_id;
1010 	vap->va_mode = ip->ino_data.mode;
1011 	vap->va_nlink = ip->ino_data.nlinks;
1012 	vap->va_uid = hammer_to_unix_xid(&ip->ino_data.uid);
1013 	vap->va_gid = hammer_to_unix_xid(&ip->ino_data.gid);
1014 	vap->va_rmajor = 0;
1015 	vap->va_rminor = 0;
1016 	vap->va_size = ip->ino_data.size;
1017 
1018 	/*
1019 	 * Special case for @@PFS softlinks.  The actual size of the
1020 	 * expanded softlink is "@@0x%016llx:%05d" == 26 bytes.
1021 	 * or for MAX_TID is    "@@-1:%05d" == 10 bytes.
1022 	 *
1023 	 * Note that userspace hammer command does not allow users to
1024 	 * create a @@PFS softlink under an existing other PFS (id!=0)
1025 	 * so the ip localization here for @@PFS softlink is always 0.
1026 	 */
1027 	if (ip->ino_data.obj_type == HAMMER_OBJTYPE_SOFTLINK &&
1028 	    ip->ino_data.size == 10 &&
1029 	    ip->obj_asof == HAMMER_MAX_TID &&
1030 	    ip->obj_localization == HAMMER_DEF_LOCALIZATION &&
1031 	    strncmp(ip->ino_data.ext.symlink, "@@PFS", 5) == 0) {
1032 		if (hammer_is_pfs_slave(&ip->pfsm->pfsd))
1033 			vap->va_size = 26;
1034 		else
1035 			vap->va_size = 10;
1036 	}
1037 
1038 	/*
1039 	 * We must provide a consistent atime and mtime for snapshots
1040 	 * so people can do a 'tar cf - ... | md5' on them and get
1041 	 * consistent results.
1042 	 */
1043 	if (ip->flags & HAMMER_INODE_RO) {
1044 		hammer_time_to_timespec(ip->ino_data.ctime, &vap->va_atime);
1045 		hammer_time_to_timespec(ip->ino_data.ctime, &vap->va_mtime);
1046 	} else {
1047 		hammer_time_to_timespec(ip->ino_data.atime, &vap->va_atime);
1048 		hammer_time_to_timespec(ip->ino_data.mtime, &vap->va_mtime);
1049 	}
1050 	hammer_time_to_timespec(ip->ino_data.ctime, &vap->va_ctime);
1051 	vap->va_flags = ip->ino_data.uflags;
1052 	vap->va_gen = 1;	/* hammer inums are unique for all time */
1053 	vap->va_blocksize = HAMMER_BUFSIZE;
1054 	if (ip->ino_data.size >= HAMMER_XDEMARC) {
1055 		vap->va_bytes = HAMMER_XBUFSIZE64_DOALIGN(ip->ino_data.size);
1056 	} else if (ip->ino_data.size > HAMMER_HBUFSIZE) {
1057 		vap->va_bytes = HAMMER_BUFSIZE64_DOALIGN(ip->ino_data.size);
1058 	} else {
1059 		vap->va_bytes = HAMMER_DATA_DOALIGN(ip->ino_data.size);
1060 	}
1061 
1062 	vap->va_type = hammer_get_vnode_type(ip->ino_data.obj_type);
1063 	vap->va_filerev = 0;	/* XXX */
1064 	vap->va_uid_uuid = ip->ino_data.uid;
1065 	vap->va_gid_uuid = ip->ino_data.gid;
1066 	vap->va_fsid_uuid = ip->hmp->fsid;
1067 	vap->va_vaflags = VA_UID_UUID_VALID | VA_GID_UUID_VALID |
1068 			  VA_FSID_UUID_VALID;
1069 
1070 	switch (ip->ino_data.obj_type) {
1071 	case HAMMER_OBJTYPE_CDEV:
1072 	case HAMMER_OBJTYPE_BDEV:
1073 		vap->va_rmajor = ip->ino_data.rmajor;
1074 		vap->va_rminor = ip->ino_data.rminor;
1075 		break;
1076 	default:
1077 		break;
1078 	}
1079 	hammer_unlock(&ip->lock);
1080 	return(0);
1081 }
1082 
1083 /*
1084  * hammer_vop_nresolve { nch, dvp, cred }
1085  *
1086  * Locate the requested directory entry.
1087  */
1088 static
1089 int
1090 hammer_vop_nresolve(struct vop_nresolve_args *ap)
1091 {
1092 	struct hammer_transaction trans;
1093 	struct namecache *ncp;
1094 	hammer_mount_t hmp;
1095 	hammer_inode_t dip;
1096 	hammer_inode_t ip;
1097 	hammer_tid_t asof;
1098 	struct hammer_cursor cursor;
1099 	struct vnode *vp;
1100 	int64_t namekey;
1101 	int error;
1102 	int i;
1103 	int nlen;
1104 	int flags;
1105 	int ispfs;
1106 	int64_t obj_id;
1107 	uint32_t localization;
1108 	uint32_t max_iterations;
1109 
1110 	/*
1111 	 * Misc initialization, plus handle as-of name extensions.  Look for
1112 	 * the '@@' extension.  Note that as-of files and directories cannot
1113 	 * be modified.
1114 	 */
1115 	dip = VTOI(ap->a_dvp);
1116 	ncp = ap->a_nch->ncp;
1117 	asof = dip->obj_asof;
1118 	localization = dip->obj_localization;	/* for code consistency */
1119 	nlen = ncp->nc_nlen;
1120 	flags = dip->flags & HAMMER_INODE_RO;
1121 	ispfs = 0;
1122 	hmp = dip->hmp;
1123 
1124 	lwkt_gettoken(&hmp->fs_token);
1125 	hammer_simple_transaction(&trans, hmp);
1126 
1127 	for (i = 0; i < nlen; ++i) {
1128 		if (ncp->nc_name[i] == '@' && ncp->nc_name[i+1] == '@') {
1129 			error = hammer_str_to_tid(ncp->nc_name + i + 2,
1130 						  &ispfs, &asof, &localization);
1131 			if (error != 0) {
1132 				i = nlen;
1133 				break;
1134 			}
1135 			if (asof != HAMMER_MAX_TID)
1136 				flags |= HAMMER_INODE_RO;
1137 			break;
1138 		}
1139 	}
1140 	nlen = i;
1141 
1142 	/*
1143 	 * If this is a PFS softlink we dive into the PFS
1144 	 */
1145 	if (ispfs && nlen == 0) {
1146 		ip = hammer_get_inode(&trans, dip, HAMMER_OBJID_ROOT,
1147 				      asof, localization,
1148 				      flags, &error);
1149 		if (error == 0) {
1150 			error = hammer_get_vnode(ip, &vp);
1151 			hammer_rel_inode(ip, 0);
1152 		} else {
1153 			vp = NULL;
1154 		}
1155 		if (error == 0) {
1156 			vn_unlock(vp);
1157 			cache_setvp(ap->a_nch, vp);
1158 			vrele(vp);
1159 		}
1160 		goto done;
1161 	}
1162 
1163 	/*
1164 	 * If there is no path component the time extension is relative to dip.
1165 	 * e.g. "fubar/@@<snapshot>"
1166 	 *
1167 	 * "." is handled by the kernel, but ".@@<snapshot>" is not.
1168 	 * e.g. "fubar/.@@<snapshot>"
1169 	 *
1170 	 * ".." is handled by the kernel.  We do not currently handle
1171 	 * "..@<snapshot>".
1172 	 */
1173 	if (nlen == 0 || (nlen == 1 && ncp->nc_name[0] == '.')) {
1174 		ip = hammer_get_inode(&trans, dip, dip->obj_id,
1175 				      asof, dip->obj_localization,
1176 				      flags, &error);
1177 		if (error == 0) {
1178 			error = hammer_get_vnode(ip, &vp);
1179 			hammer_rel_inode(ip, 0);
1180 		} else {
1181 			vp = NULL;
1182 		}
1183 		if (error == 0) {
1184 			vn_unlock(vp);
1185 			cache_setvp(ap->a_nch, vp);
1186 			vrele(vp);
1187 		}
1188 		goto done;
1189 	}
1190 
1191 	/*
1192 	 * Calculate the namekey and setup the key range for the scan.  This
1193 	 * works kinda like a chained hash table where the lower 32 bits
1194 	 * of the namekey synthesize the chain.
1195 	 *
1196 	 * The key range is inclusive of both key_beg and key_end.
1197 	 */
1198 	namekey = hammer_direntry_namekey(dip, ncp->nc_name, nlen,
1199 					   &max_iterations);
1200 
1201 	error = hammer_init_cursor(&trans, &cursor, &dip->cache[1], dip);
1202 	cursor.key_beg.localization = dip->obj_localization |
1203 				      hammer_dir_localization(dip);
1204         cursor.key_beg.obj_id = dip->obj_id;
1205 	cursor.key_beg.key = namekey;
1206         cursor.key_beg.create_tid = 0;
1207         cursor.key_beg.delete_tid = 0;
1208         cursor.key_beg.rec_type = HAMMER_RECTYPE_DIRENTRY;
1209         cursor.key_beg.obj_type = 0;
1210 
1211 	cursor.key_end = cursor.key_beg;
1212 	cursor.key_end.key += max_iterations;
1213 	cursor.asof = asof;
1214 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF;
1215 
1216 	/*
1217 	 * Scan all matching records (the chain), locate the one matching
1218 	 * the requested path component.
1219 	 *
1220 	 * The hammer_ip_*() functions merge in-memory records with on-disk
1221 	 * records for the purposes of the search.
1222 	 */
1223 	obj_id = 0;
1224 	localization = HAMMER_DEF_LOCALIZATION;
1225 
1226 	if (error == 0) {
1227 		error = hammer_ip_first(&cursor);
1228 		while (error == 0) {
1229 			error = hammer_ip_resolve_data(&cursor);
1230 			if (error)
1231 				break;
1232 			if (nlen == cursor.leaf->data_len - HAMMER_ENTRY_NAME_OFF &&
1233 			    bcmp(ncp->nc_name, cursor.data->entry.name, nlen) == 0) {
1234 				obj_id = cursor.data->entry.obj_id;
1235 				localization = cursor.data->entry.localization;
1236 				break;
1237 			}
1238 			error = hammer_ip_next(&cursor);
1239 		}
1240 	}
1241 	hammer_done_cursor(&cursor);
1242 
1243 	/*
1244 	 * Lookup the obj_id.  This should always succeed.  If it does not
1245 	 * the filesystem may be damaged and we return a dummy inode.
1246 	 */
1247 	if (error == 0) {
1248 		ip = hammer_get_inode(&trans, dip, obj_id,
1249 				      asof, localization,
1250 				      flags, &error);
1251 		if (error == ENOENT) {
1252 			hkprintf("WARNING: Missing inode for dirent \"%s\"\n"
1253 				"\tobj_id = %016jx, asof=%016jx, lo=%08x\n",
1254 				ncp->nc_name,
1255 				(intmax_t)obj_id, (intmax_t)asof,
1256 				localization);
1257 			error = 0;
1258 			ip = hammer_get_dummy_inode(&trans, dip, obj_id,
1259 						    asof, localization,
1260 						    flags, &error);
1261 		}
1262 		if (error == 0) {
1263 			error = hammer_get_vnode(ip, &vp);
1264 			hammer_rel_inode(ip, 0);
1265 		} else {
1266 			vp = NULL;
1267 		}
1268 		if (error == 0) {
1269 			vn_unlock(vp);
1270 			cache_setvp(ap->a_nch, vp);
1271 			vrele(vp);
1272 		}
1273 	} else if (error == ENOENT) {
1274 		cache_setvp(ap->a_nch, NULL);
1275 	}
1276 done:
1277 	hammer_done_transaction(&trans);
1278 	lwkt_reltoken(&hmp->fs_token);
1279 	return (error);
1280 }
1281 
1282 /*
1283  * hammer_vop_nlookupdotdot { dvp, vpp, cred }
1284  *
1285  * Locate the parent directory of a directory vnode.
1286  *
1287  * dvp is referenced but not locked.  *vpp must be returned referenced and
1288  * locked.  A parent_obj_id of 0 indicates that we are at the root.
1289  *
1290  * NOTE: as-of sequences are not linked into the directory structure.  If
1291  * we are at the root with a different asof then the mount point, reload
1292  * the same directory with the mount point's asof.   I'm not sure what this
1293  * will do to NFS.  We encode ASOF stamps in NFS file handles so it might not
1294  * get confused, but it hasn't been tested.
1295  */
1296 static
1297 int
1298 hammer_vop_nlookupdotdot(struct vop_nlookupdotdot_args *ap)
1299 {
1300 	struct hammer_transaction trans;
1301 	hammer_inode_t dip;
1302 	hammer_inode_t ip;
1303 	hammer_mount_t hmp;
1304 	int64_t parent_obj_id;
1305 	uint32_t parent_obj_localization;
1306 	hammer_tid_t asof;
1307 	int error;
1308 
1309 	dip = VTOI(ap->a_dvp);
1310 	asof = dip->obj_asof;
1311 	hmp = dip->hmp;
1312 
1313 	/*
1314 	 * Whos are parent?  This could be the root of a pseudo-filesystem
1315 	 * whos parent is in another localization domain.
1316 	 */
1317 	lwkt_gettoken(&hmp->fs_token);
1318 	parent_obj_id = dip->ino_data.parent_obj_id;
1319 	if (dip->obj_id == HAMMER_OBJID_ROOT)
1320 		parent_obj_localization = HAMMER_DEF_LOCALIZATION;
1321 	else
1322 		parent_obj_localization = dip->obj_localization;
1323 
1324 	/*
1325 	 * It's probably a PFS root when dip->ino_data.parent_obj_id is 0.
1326 	 */
1327 	if (parent_obj_id == 0) {
1328 		if (dip->obj_id == HAMMER_OBJID_ROOT &&
1329 		   asof != hmp->asof) {
1330 			parent_obj_id = dip->obj_id;
1331 			asof = hmp->asof;
1332 			*ap->a_fakename = kmalloc(19, M_TEMP, M_WAITOK);
1333 			ksnprintf(*ap->a_fakename, 19, "0x%016jx",
1334 				  (intmax_t)dip->obj_asof);
1335 		} else {
1336 			*ap->a_vpp = NULL;
1337 			lwkt_reltoken(&hmp->fs_token);
1338 			return ENOENT;
1339 		}
1340 	}
1341 
1342 	hammer_simple_transaction(&trans, hmp);
1343 
1344 	ip = hammer_get_inode(&trans, dip, parent_obj_id,
1345 			      asof, parent_obj_localization,
1346 			      dip->flags, &error);
1347 	if (ip) {
1348 		error = hammer_get_vnode(ip, ap->a_vpp);
1349 		hammer_rel_inode(ip, 0);
1350 	} else {
1351 		*ap->a_vpp = NULL;
1352 	}
1353 	hammer_done_transaction(&trans);
1354 	lwkt_reltoken(&hmp->fs_token);
1355 	return (error);
1356 }
1357 
1358 /*
1359  * hammer_vop_nlink { nch, dvp, vp, cred }
1360  */
1361 static
1362 int
1363 hammer_vop_nlink(struct vop_nlink_args *ap)
1364 {
1365 	struct hammer_transaction trans;
1366 	hammer_inode_t dip;
1367 	hammer_inode_t ip;
1368 	struct nchandle *nch;
1369 	hammer_mount_t hmp;
1370 	int error;
1371 
1372 	if (ap->a_dvp->v_mount != ap->a_vp->v_mount)
1373 		return(EXDEV);
1374 
1375 	nch = ap->a_nch;
1376 	dip = VTOI(ap->a_dvp);
1377 	ip = VTOI(ap->a_vp);
1378 	hmp = dip->hmp;
1379 
1380 	if (dip->obj_localization != ip->obj_localization)
1381 		return(EXDEV);
1382 
1383 	if (dip->flags & HAMMER_INODE_RO)
1384 		return (EROFS);
1385 	if (ip->flags & HAMMER_INODE_RO)
1386 		return (EROFS);
1387 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
1388 		return (error);
1389 
1390 	/*
1391 	 * Create a transaction to cover the operations we perform.
1392 	 */
1393 	lwkt_gettoken(&hmp->fs_token);
1394 	hammer_start_transaction(&trans, hmp);
1395 
1396 	/*
1397 	 * Add the filesystem object to the directory.  Note that neither
1398 	 * dip nor ip are referenced or locked, but their vnodes are
1399 	 * referenced.  This function will bump the inode's link count.
1400 	 */
1401 	error = hammer_ip_add_direntry(&trans, dip,
1402 					nch->ncp->nc_name, nch->ncp->nc_nlen,
1403 					ip);
1404 
1405 	/*
1406 	 * Finish up.
1407 	 */
1408 	if (error == 0) {
1409 		cache_setunresolved(nch);
1410 		cache_setvp(nch, ap->a_vp);
1411 	}
1412 	hammer_done_transaction(&trans);
1413 	hammer_knote(ap->a_vp, NOTE_LINK);
1414 	hammer_knote(ap->a_dvp, NOTE_WRITE);
1415 	lwkt_reltoken(&hmp->fs_token);
1416 	return (error);
1417 }
1418 
1419 /*
1420  * hammer_vop_nmkdir { nch, dvp, vpp, cred, vap }
1421  *
1422  * The operating system has already ensured that the directory entry
1423  * does not exist and done all appropriate namespace locking.
1424  */
1425 static
1426 int
1427 hammer_vop_nmkdir(struct vop_nmkdir_args *ap)
1428 {
1429 	struct hammer_transaction trans;
1430 	hammer_inode_t dip;
1431 	hammer_inode_t nip;
1432 	struct nchandle *nch;
1433 	hammer_mount_t hmp;
1434 	int error;
1435 
1436 	nch = ap->a_nch;
1437 	dip = VTOI(ap->a_dvp);
1438 	hmp = dip->hmp;
1439 
1440 	if (dip->flags & HAMMER_INODE_RO)
1441 		return (EROFS);
1442 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
1443 		return (error);
1444 
1445 	/*
1446 	 * Create a transaction to cover the operations we perform.
1447 	 */
1448 	lwkt_gettoken(&hmp->fs_token);
1449 	hammer_start_transaction(&trans, hmp);
1450 
1451 	/*
1452 	 * Create a new filesystem object of the requested type.  The
1453 	 * returned inode will be referenced but not locked.
1454 	 */
1455 	error = hammer_create_inode(&trans, ap->a_vap, ap->a_cred,
1456 				    dip, nch->ncp->nc_name, nch->ncp->nc_nlen,
1457 				    NULL, &nip);
1458 	if (error) {
1459 		hammer_done_transaction(&trans);
1460 		*ap->a_vpp = NULL;
1461 		lwkt_reltoken(&hmp->fs_token);
1462 		return (error);
1463 	}
1464 	/*
1465 	 * Add the new filesystem object to the directory.  This will also
1466 	 * bump the inode's link count.
1467 	 */
1468 	error = hammer_ip_add_direntry(&trans, dip,
1469 					nch->ncp->nc_name, nch->ncp->nc_nlen,
1470 					nip);
1471 	if (error)
1472 		hkprintf("hammer_mkdir (add) error %d\n", error);
1473 
1474 	/*
1475 	 * Finish up.
1476 	 */
1477 	if (error) {
1478 		hammer_rel_inode(nip, 0);
1479 		*ap->a_vpp = NULL;
1480 	} else {
1481 		error = hammer_get_vnode(nip, ap->a_vpp);
1482 		hammer_rel_inode(nip, 0);
1483 		if (error == 0) {
1484 			cache_setunresolved(ap->a_nch);
1485 			cache_setvp(ap->a_nch, *ap->a_vpp);
1486 		}
1487 	}
1488 	hammer_done_transaction(&trans);
1489 	if (error == 0)
1490 		hammer_knote(ap->a_dvp, NOTE_WRITE | NOTE_LINK);
1491 	lwkt_reltoken(&hmp->fs_token);
1492 	return (error);
1493 }
1494 
1495 /*
1496  * hammer_vop_nmknod { nch, dvp, vpp, cred, vap }
1497  *
1498  * The operating system has already ensured that the directory entry
1499  * does not exist and done all appropriate namespace locking.
1500  */
1501 static
1502 int
1503 hammer_vop_nmknod(struct vop_nmknod_args *ap)
1504 {
1505 	struct hammer_transaction trans;
1506 	hammer_inode_t dip;
1507 	hammer_inode_t nip;
1508 	struct nchandle *nch;
1509 	hammer_mount_t hmp;
1510 	int error;
1511 
1512 	nch = ap->a_nch;
1513 	dip = VTOI(ap->a_dvp);
1514 	hmp = dip->hmp;
1515 
1516 	if (dip->flags & HAMMER_INODE_RO)
1517 		return (EROFS);
1518 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
1519 		return (error);
1520 
1521 	/*
1522 	 * Create a transaction to cover the operations we perform.
1523 	 */
1524 	lwkt_gettoken(&hmp->fs_token);
1525 	hammer_start_transaction(&trans, hmp);
1526 
1527 	/*
1528 	 * Create a new filesystem object of the requested type.  The
1529 	 * returned inode will be referenced but not locked.
1530 	 *
1531 	 * If mknod specifies a directory a pseudo-fs is created.
1532 	 */
1533 	error = hammer_create_inode(&trans, ap->a_vap, ap->a_cred,
1534 				    dip, nch->ncp->nc_name, nch->ncp->nc_nlen,
1535 				    NULL, &nip);
1536 	if (error) {
1537 		hammer_done_transaction(&trans);
1538 		*ap->a_vpp = NULL;
1539 		lwkt_reltoken(&hmp->fs_token);
1540 		return (error);
1541 	}
1542 
1543 	/*
1544 	 * Add the new filesystem object to the directory.  This will also
1545 	 * bump the inode's link count.
1546 	 */
1547 	error = hammer_ip_add_direntry(&trans, dip,
1548 					nch->ncp->nc_name, nch->ncp->nc_nlen,
1549 					nip);
1550 
1551 	/*
1552 	 * Finish up.
1553 	 */
1554 	if (error) {
1555 		hammer_rel_inode(nip, 0);
1556 		*ap->a_vpp = NULL;
1557 	} else {
1558 		error = hammer_get_vnode(nip, ap->a_vpp);
1559 		hammer_rel_inode(nip, 0);
1560 		if (error == 0) {
1561 			cache_setunresolved(ap->a_nch);
1562 			cache_setvp(ap->a_nch, *ap->a_vpp);
1563 		}
1564 	}
1565 	hammer_done_transaction(&trans);
1566 	if (error == 0)
1567 		hammer_knote(ap->a_dvp, NOTE_WRITE);
1568 	lwkt_reltoken(&hmp->fs_token);
1569 	return (error);
1570 }
1571 
1572 /*
1573  * hammer_vop_open { vp, mode, cred, fp }
1574  *
1575  * MPSAFE (does not require fs_token)
1576  */
1577 static
1578 int
1579 hammer_vop_open(struct vop_open_args *ap)
1580 {
1581 	hammer_inode_t ip;
1582 
1583 	ip = VTOI(ap->a_vp);
1584 
1585 	if ((ap->a_mode & FWRITE) && (ip->flags & HAMMER_INODE_RO))
1586 		return (EROFS);
1587 	return(vop_stdopen(ap));
1588 }
1589 
1590 /*
1591  * hammer_vop_print { vp }
1592  */
1593 static
1594 int
1595 hammer_vop_print(struct vop_print_args *ap)
1596 {
1597 	return EOPNOTSUPP;
1598 }
1599 
1600 /*
1601  * hammer_vop_readdir { vp, uio, cred, *eofflag, *ncookies, off_t **cookies }
1602  */
1603 static
1604 int
1605 hammer_vop_readdir(struct vop_readdir_args *ap)
1606 {
1607 	struct hammer_transaction trans;
1608 	struct hammer_cursor cursor;
1609 	hammer_inode_t ip;
1610 	hammer_mount_t hmp;
1611 	struct uio *uio;
1612 	hammer_base_elm_t base;
1613 	int error;
1614 	int cookie_index;
1615 	int ncookies;
1616 	off_t *cookies;
1617 	off_t saveoff;
1618 	int r;
1619 	int dtype;
1620 
1621 	ip = VTOI(ap->a_vp);
1622 	uio = ap->a_uio;
1623 	saveoff = uio->uio_offset;
1624 	hmp = ip->hmp;
1625 
1626 	if (ap->a_ncookies) {
1627 		ncookies = uio->uio_resid / 16 + 1;
1628 		if (ncookies > 1024)
1629 			ncookies = 1024;
1630 		cookies = kmalloc(ncookies * sizeof(off_t), M_TEMP, M_WAITOK);
1631 		cookie_index = 0;
1632 	} else {
1633 		ncookies = -1;
1634 		cookies = NULL;
1635 		cookie_index = 0;
1636 	}
1637 
1638 	lwkt_gettoken(&hmp->fs_token);
1639 	hammer_simple_transaction(&trans, hmp);
1640 
1641 	/*
1642 	 * Handle artificial entries
1643 	 *
1644 	 * It should be noted that the minimum value for a directory
1645 	 * hash key on-media is 0x0000000100000000, so we can use anything
1646 	 * less then that to represent our 'special' key space.
1647 	 */
1648 	error = 0;
1649 	if (saveoff == 0) {
1650 		r = vop_write_dirent(&error, uio, ip->obj_id, DT_DIR, 1, ".");
1651 		if (r)
1652 			goto done;
1653 		if (cookies)
1654 			cookies[cookie_index] = saveoff;
1655 		++saveoff;
1656 		++cookie_index;
1657 		if (cookie_index == ncookies)
1658 			goto done;
1659 	}
1660 	if (saveoff == 1) {
1661 		if (ip->ino_data.parent_obj_id) {
1662 			r = vop_write_dirent(&error, uio,
1663 					     ip->ino_data.parent_obj_id,
1664 					     DT_DIR, 2, "..");
1665 		} else {
1666 			r = vop_write_dirent(&error, uio,
1667 					     ip->obj_id, DT_DIR, 2, "..");
1668 		}
1669 		if (r)
1670 			goto done;
1671 		if (cookies)
1672 			cookies[cookie_index] = saveoff;
1673 		++saveoff;
1674 		++cookie_index;
1675 		if (cookie_index == ncookies)
1676 			goto done;
1677 	}
1678 
1679 	/*
1680 	 * Key range (begin and end inclusive) to scan.  Directory keys
1681 	 * directly translate to a 64 bit 'seek' position.
1682 	 */
1683 	hammer_init_cursor(&trans, &cursor, &ip->cache[1], ip);
1684 	cursor.key_beg.localization = ip->obj_localization |
1685 				      hammer_dir_localization(ip);
1686 	cursor.key_beg.obj_id = ip->obj_id;
1687 	cursor.key_beg.create_tid = 0;
1688 	cursor.key_beg.delete_tid = 0;
1689         cursor.key_beg.rec_type = HAMMER_RECTYPE_DIRENTRY;
1690 	cursor.key_beg.obj_type = 0;
1691 	cursor.key_beg.key = saveoff;
1692 
1693 	cursor.key_end = cursor.key_beg;
1694 	cursor.key_end.key = HAMMER_MAX_KEY;
1695 	cursor.asof = ip->obj_asof;
1696 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF;
1697 
1698 	error = hammer_ip_first(&cursor);
1699 
1700 	while (error == 0) {
1701 		error = hammer_ip_resolve_data(&cursor);
1702 		if (error)
1703 			break;
1704 		base = &cursor.leaf->base;
1705 		saveoff = base->key;
1706 		KKASSERT(cursor.leaf->data_len > HAMMER_ENTRY_NAME_OFF);
1707 
1708 		if (base->obj_id != ip->obj_id)
1709 			hpanic("bad record at %p", cursor.node);
1710 
1711 		dtype = hammer_get_dtype(cursor.leaf->base.obj_type);
1712 		r = vop_write_dirent(
1713 			     &error, uio, cursor.data->entry.obj_id,
1714 			     dtype,
1715 			     cursor.leaf->data_len - HAMMER_ENTRY_NAME_OFF ,
1716 			     (void *)cursor.data->entry.name);
1717 		if (r)
1718 			break;
1719 		++saveoff;
1720 		if (cookies)
1721 			cookies[cookie_index] = base->key;
1722 		++cookie_index;
1723 		if (cookie_index == ncookies)
1724 			break;
1725 		error = hammer_ip_next(&cursor);
1726 	}
1727 	hammer_done_cursor(&cursor);
1728 
1729 done:
1730 	hammer_done_transaction(&trans);
1731 
1732 	if (ap->a_eofflag)
1733 		*ap->a_eofflag = (error == ENOENT);
1734 	uio->uio_offset = saveoff;
1735 	if (error && cookie_index == 0) {
1736 		if (error == ENOENT)
1737 			error = 0;
1738 		if (cookies) {
1739 			kfree(cookies, M_TEMP);
1740 			*ap->a_ncookies = 0;
1741 			*ap->a_cookies = NULL;
1742 		}
1743 	} else {
1744 		if (error == ENOENT)
1745 			error = 0;
1746 		if (cookies) {
1747 			*ap->a_ncookies = cookie_index;
1748 			*ap->a_cookies = cookies;
1749 		}
1750 	}
1751 	lwkt_reltoken(&hmp->fs_token);
1752 	return(error);
1753 }
1754 
1755 /*
1756  * hammer_vop_readlink { vp, uio, cred }
1757  */
1758 static
1759 int
1760 hammer_vop_readlink(struct vop_readlink_args *ap)
1761 {
1762 	struct hammer_transaction trans;
1763 	struct hammer_cursor cursor;
1764 	hammer_inode_t ip;
1765 	hammer_mount_t hmp;
1766 	char buf[32];
1767 	uint32_t localization;
1768 	hammer_pseudofs_inmem_t pfsm;
1769 	int error;
1770 
1771 	ip = VTOI(ap->a_vp);
1772 	hmp = ip->hmp;
1773 
1774 	lwkt_gettoken(&hmp->fs_token);
1775 
1776 	/*
1777 	 * Shortcut if the symlink data was stuffed into ino_data.
1778 	 *
1779 	 * Also expand special "@@PFS%05d" softlinks (expansion only
1780 	 * occurs for non-historical (current) accesses made from the
1781 	 * primary filesystem).
1782 	 *
1783 	 * Note that userspace hammer command does not allow users to
1784 	 * create a @@PFS softlink under an existing other PFS (id!=0)
1785 	 * so the ip localization here for @@PFS softlink is always 0.
1786 	 */
1787 	if (ip->ino_data.size <= HAMMER_INODE_BASESYMLEN) {
1788 		char *ptr;
1789 		int bytes;
1790 
1791 		ptr = ip->ino_data.ext.symlink;
1792 		bytes = (int)ip->ino_data.size;
1793 		if (bytes == 10 &&
1794 		    ip->obj_asof == HAMMER_MAX_TID &&
1795 		    ip->obj_localization == HAMMER_DEF_LOCALIZATION &&
1796 		    strncmp(ptr, "@@PFS", 5) == 0) {
1797 			hammer_simple_transaction(&trans, hmp);
1798 			bcopy(ptr + 5, buf, 5);
1799 			buf[5] = 0;
1800 			localization = pfs_to_lo(strtoul(buf, NULL, 10));
1801 			pfsm = hammer_load_pseudofs(&trans, localization,
1802 						    &error);
1803 			if (error == 0) {
1804 				if (hammer_is_pfs_slave(&pfsm->pfsd)) {
1805 					/* vap->va_size == 26 */
1806 					ksnprintf(buf, sizeof(buf),
1807 						  "@@0x%016jx:%05d",
1808 						  (intmax_t)pfsm->pfsd.sync_end_tid,
1809 						  lo_to_pfs(localization));
1810 				} else {
1811 					/* vap->va_size == 10 */
1812 					ksnprintf(buf, sizeof(buf),
1813 						  "@@-1:%05d",
1814 						  lo_to_pfs(localization));
1815 				}
1816 				ptr = buf;
1817 				bytes = strlen(buf);
1818 			}
1819 			if (pfsm)
1820 				hammer_rel_pseudofs(hmp, pfsm);
1821 			hammer_done_transaction(&trans);
1822 		}
1823 		error = uiomove(ptr, bytes, ap->a_uio);
1824 		lwkt_reltoken(&hmp->fs_token);
1825 		return(error);
1826 	}
1827 
1828 	/*
1829 	 * Long version
1830 	 */
1831 	hammer_simple_transaction(&trans, hmp);
1832 	hammer_init_cursor(&trans, &cursor, &ip->cache[1], ip);
1833 
1834 	/*
1835 	 * Key range (begin and end inclusive) to scan.  Directory keys
1836 	 * directly translate to a 64 bit 'seek' position.
1837 	 */
1838 	cursor.key_beg.localization = ip->obj_localization |
1839 				      HAMMER_LOCALIZE_MISC;
1840 	cursor.key_beg.obj_id = ip->obj_id;
1841 	cursor.key_beg.create_tid = 0;
1842 	cursor.key_beg.delete_tid = 0;
1843         cursor.key_beg.rec_type = HAMMER_RECTYPE_FIX;
1844 	cursor.key_beg.obj_type = 0;
1845 	cursor.key_beg.key = HAMMER_FIXKEY_SYMLINK;
1846 	cursor.asof = ip->obj_asof;
1847 	cursor.flags |= HAMMER_CURSOR_ASOF;
1848 
1849 	error = hammer_ip_lookup(&cursor);
1850 	if (error == 0) {
1851 		error = hammer_ip_resolve_data(&cursor);
1852 		if (error == 0) {
1853 			KKASSERT(cursor.leaf->data_len >=
1854 				 HAMMER_SYMLINK_NAME_OFF);
1855 			error = uiomove(cursor.data->symlink.name,
1856 					cursor.leaf->data_len -
1857 						HAMMER_SYMLINK_NAME_OFF,
1858 					ap->a_uio);
1859 		}
1860 	}
1861 	hammer_done_cursor(&cursor);
1862 	hammer_done_transaction(&trans);
1863 	lwkt_reltoken(&hmp->fs_token);
1864 	return(error);
1865 }
1866 
1867 /*
1868  * hammer_vop_nremove { nch, dvp, cred }
1869  */
1870 static
1871 int
1872 hammer_vop_nremove(struct vop_nremove_args *ap)
1873 {
1874 	struct hammer_transaction trans;
1875 	hammer_inode_t dip;
1876 	hammer_mount_t hmp;
1877 	int error;
1878 
1879 	dip = VTOI(ap->a_dvp);
1880 	hmp = dip->hmp;
1881 
1882 	if (hammer_nohistory(dip) == 0 &&
1883 	    (error = hammer_checkspace(hmp, HAMMER_CHKSPC_REMOVE)) != 0) {
1884 		return (error);
1885 	}
1886 
1887 	lwkt_gettoken(&hmp->fs_token);
1888 	hammer_start_transaction(&trans, hmp);
1889 	error = hammer_dounlink(&trans, ap->a_nch, ap->a_dvp, ap->a_cred, 0, 0);
1890 	hammer_done_transaction(&trans);
1891 	if (error == 0)
1892 		hammer_knote(ap->a_dvp, NOTE_WRITE);
1893 	lwkt_reltoken(&hmp->fs_token);
1894 	return (error);
1895 }
1896 
1897 /*
1898  * hammer_vop_nrename { fnch, tnch, fdvp, tdvp, cred }
1899  */
1900 static
1901 int
1902 hammer_vop_nrename(struct vop_nrename_args *ap)
1903 {
1904 	struct hammer_transaction trans;
1905 	struct namecache *fncp;
1906 	struct namecache *tncp;
1907 	hammer_inode_t fdip;
1908 	hammer_inode_t tdip;
1909 	hammer_inode_t ip;
1910 	hammer_mount_t hmp;
1911 	struct hammer_cursor cursor;
1912 	int64_t namekey;
1913 	uint32_t max_iterations;
1914 	int nlen, error;
1915 
1916 	if (ap->a_fdvp->v_mount != ap->a_tdvp->v_mount)
1917 		return(EXDEV);
1918 	if (ap->a_fdvp->v_mount != ap->a_fnch->ncp->nc_vp->v_mount)
1919 		return(EXDEV);
1920 
1921 	fdip = VTOI(ap->a_fdvp);
1922 	tdip = VTOI(ap->a_tdvp);
1923 	fncp = ap->a_fnch->ncp;
1924 	tncp = ap->a_tnch->ncp;
1925 	ip = VTOI(fncp->nc_vp);
1926 	KKASSERT(ip != NULL);
1927 
1928 	hmp = ip->hmp;
1929 
1930 	if (fdip->obj_localization != tdip->obj_localization)
1931 		return(EXDEV);
1932 	if (fdip->obj_localization != ip->obj_localization)
1933 		return(EXDEV);
1934 
1935 	if (fdip->flags & HAMMER_INODE_RO)
1936 		return (EROFS);
1937 	if (tdip->flags & HAMMER_INODE_RO)
1938 		return (EROFS);
1939 	if (ip->flags & HAMMER_INODE_RO)
1940 		return (EROFS);
1941 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
1942 		return (error);
1943 
1944 	lwkt_gettoken(&hmp->fs_token);
1945 	hammer_start_transaction(&trans, hmp);
1946 
1947 	/*
1948 	 * Remove tncp from the target directory and then link ip as
1949 	 * tncp. XXX pass trans to dounlink
1950 	 *
1951 	 * Force the inode sync-time to match the transaction so it is
1952 	 * in-sync with the creation of the target directory entry.
1953 	 */
1954 	error = hammer_dounlink(&trans, ap->a_tnch, ap->a_tdvp,
1955 				ap->a_cred, 0, -1);
1956 	if (error == 0 || error == ENOENT) {
1957 		error = hammer_ip_add_direntry(&trans, tdip,
1958 						tncp->nc_name, tncp->nc_nlen,
1959 						ip);
1960 		if (error == 0) {
1961 			ip->ino_data.parent_obj_id = tdip->obj_id;
1962 			ip->ino_data.ctime = trans.time;
1963 			hammer_modify_inode(&trans, ip, HAMMER_INODE_DDIRTY);
1964 		}
1965 	}
1966 	if (error)
1967 		goto failed; /* XXX */
1968 
1969 	/*
1970 	 * Locate the record in the originating directory and remove it.
1971 	 *
1972 	 * Calculate the namekey and setup the key range for the scan.  This
1973 	 * works kinda like a chained hash table where the lower 32 bits
1974 	 * of the namekey synthesize the chain.
1975 	 *
1976 	 * The key range is inclusive of both key_beg and key_end.
1977 	 */
1978 	namekey = hammer_direntry_namekey(fdip, fncp->nc_name, fncp->nc_nlen,
1979 					   &max_iterations);
1980 retry:
1981 	hammer_init_cursor(&trans, &cursor, &fdip->cache[1], fdip);
1982 	cursor.key_beg.localization = fdip->obj_localization |
1983 				      hammer_dir_localization(fdip);
1984         cursor.key_beg.obj_id = fdip->obj_id;
1985 	cursor.key_beg.key = namekey;
1986         cursor.key_beg.create_tid = 0;
1987         cursor.key_beg.delete_tid = 0;
1988         cursor.key_beg.rec_type = HAMMER_RECTYPE_DIRENTRY;
1989         cursor.key_beg.obj_type = 0;
1990 
1991 	cursor.key_end = cursor.key_beg;
1992 	cursor.key_end.key += max_iterations;
1993 	cursor.asof = fdip->obj_asof;
1994 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF;
1995 
1996 	/*
1997 	 * Scan all matching records (the chain), locate the one matching
1998 	 * the requested path component.
1999 	 *
2000 	 * The hammer_ip_*() functions merge in-memory records with on-disk
2001 	 * records for the purposes of the search.
2002 	 */
2003 	error = hammer_ip_first(&cursor);
2004 	while (error == 0) {
2005 		if (hammer_ip_resolve_data(&cursor) != 0)
2006 			break;
2007 		nlen = cursor.leaf->data_len - HAMMER_ENTRY_NAME_OFF;
2008 		KKASSERT(nlen > 0);
2009 		if (fncp->nc_nlen == nlen &&
2010 		    bcmp(fncp->nc_name, cursor.data->entry.name, nlen) == 0) {
2011 			break;
2012 		}
2013 		error = hammer_ip_next(&cursor);
2014 	}
2015 
2016 	/*
2017 	 * If all is ok we have to get the inode so we can adjust nlinks.
2018 	 *
2019 	 * WARNING: hammer_ip_del_direntry() may have to terminate the
2020 	 * cursor to avoid a recursion.  It's ok to call hammer_done_cursor()
2021 	 * twice.
2022 	 */
2023 	if (error == 0)
2024 		error = hammer_ip_del_direntry(&trans, &cursor, fdip, ip);
2025 
2026 	/*
2027 	 * XXX A deadlock here will break rename's atomicy for the purposes
2028 	 * of crash recovery.
2029 	 */
2030 	if (error == EDEADLK) {
2031 		hammer_done_cursor(&cursor);
2032 		goto retry;
2033 	}
2034 
2035 	/*
2036 	 * Cleanup and tell the kernel that the rename succeeded.
2037 	 *
2038 	 * NOTE: ip->vp, if non-NULL, cannot be directly referenced
2039 	 *	 without formally acquiring the vp since the vp might
2040 	 *	 have zero refs on it, or in the middle of a reclaim,
2041 	 *	 etc.
2042 	 */
2043         hammer_done_cursor(&cursor);
2044 	if (error == 0) {
2045 		cache_rename(ap->a_fnch, ap->a_tnch);
2046 		hammer_knote(ap->a_fdvp, NOTE_WRITE);
2047 		hammer_knote(ap->a_tdvp, NOTE_WRITE);
2048 		while (ip->vp) {
2049 			struct vnode *vp;
2050 
2051 			error = hammer_get_vnode(ip, &vp);
2052 			if (error == 0 && vp) {
2053 				vn_unlock(vp);
2054 				hammer_knote(ip->vp, NOTE_RENAME);
2055 				vrele(vp);
2056 				break;
2057 			}
2058 			hdkprintf("ip/vp race2 avoided\n");
2059 		}
2060 	}
2061 
2062 failed:
2063 	hammer_done_transaction(&trans);
2064 	lwkt_reltoken(&hmp->fs_token);
2065 	return (error);
2066 }
2067 
2068 /*
2069  * hammer_vop_nrmdir { nch, dvp, cred }
2070  */
2071 static
2072 int
2073 hammer_vop_nrmdir(struct vop_nrmdir_args *ap)
2074 {
2075 	struct hammer_transaction trans;
2076 	hammer_inode_t dip;
2077 	hammer_mount_t hmp;
2078 	int error;
2079 
2080 	dip = VTOI(ap->a_dvp);
2081 	hmp = dip->hmp;
2082 
2083 	if (hammer_nohistory(dip) == 0 &&
2084 	    (error = hammer_checkspace(hmp, HAMMER_CHKSPC_REMOVE)) != 0) {
2085 		return (error);
2086 	}
2087 
2088 	lwkt_gettoken(&hmp->fs_token);
2089 	hammer_start_transaction(&trans, hmp);
2090 	error = hammer_dounlink(&trans, ap->a_nch, ap->a_dvp, ap->a_cred, 0, 1);
2091 	hammer_done_transaction(&trans);
2092 	if (error == 0)
2093 		hammer_knote(ap->a_dvp, NOTE_WRITE | NOTE_LINK);
2094 	lwkt_reltoken(&hmp->fs_token);
2095 	return (error);
2096 }
2097 
2098 /*
2099  * hammer_vop_markatime { vp, cred }
2100  */
2101 static
2102 int
2103 hammer_vop_markatime(struct vop_markatime_args *ap)
2104 {
2105 	struct hammer_transaction trans;
2106 	hammer_inode_t ip;
2107 	hammer_mount_t hmp;
2108 
2109 	ip = VTOI(ap->a_vp);
2110 	if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY)
2111 		return (EROFS);
2112 	if (ip->flags & HAMMER_INODE_RO)
2113 		return (EROFS);
2114 	hmp = ip->hmp;
2115 	if (hmp->mp->mnt_flag & MNT_NOATIME)
2116 		return (0);
2117 	lwkt_gettoken(&hmp->fs_token);
2118 	hammer_start_transaction(&trans, hmp);
2119 
2120 	ip->ino_data.atime = trans.time;
2121 	hammer_modify_inode(&trans, ip, HAMMER_INODE_ATIME);
2122 	hammer_done_transaction(&trans);
2123 	hammer_knote(ap->a_vp, NOTE_ATTRIB);
2124 	lwkt_reltoken(&hmp->fs_token);
2125 	return (0);
2126 }
2127 
2128 /*
2129  * hammer_vop_setattr { vp, vap, cred }
2130  */
2131 static
2132 int
2133 hammer_vop_setattr(struct vop_setattr_args *ap)
2134 {
2135 	struct hammer_transaction trans;
2136 	hammer_inode_t ip;
2137 	struct vattr *vap;
2138 	hammer_mount_t hmp;
2139 	int modflags;
2140 	int error;
2141 	int truncating;
2142 	int blksize;
2143 	int kflags;
2144 #if 0
2145 	int64_t aligned_size;
2146 #endif
2147 	uint32_t flags;
2148 
2149 	vap = ap->a_vap;
2150 	ip = ap->a_vp->v_data;
2151 	modflags = 0;
2152 	kflags = 0;
2153 	hmp = ip->hmp;
2154 
2155 	if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY)
2156 		return(EROFS);
2157 	if (ip->flags & HAMMER_INODE_RO)
2158 		return (EROFS);
2159 	if (hammer_nohistory(ip) == 0 &&
2160 	    (error = hammer_checkspace(hmp, HAMMER_CHKSPC_REMOVE)) != 0) {
2161 		return (error);
2162 	}
2163 
2164 	lwkt_gettoken(&hmp->fs_token);
2165 	hammer_start_transaction(&trans, hmp);
2166 	error = 0;
2167 
2168 	if (vap->va_flags != VNOVAL) {
2169 		flags = ip->ino_data.uflags;
2170 		error = vop_helper_setattr_flags(&flags, vap->va_flags,
2171 					 hammer_to_unix_xid(&ip->ino_data.uid),
2172 					 ap->a_cred);
2173 		if (error == 0) {
2174 			if (ip->ino_data.uflags != flags) {
2175 				ip->ino_data.uflags = flags;
2176 				ip->ino_data.ctime = trans.time;
2177 				modflags |= HAMMER_INODE_DDIRTY;
2178 				kflags |= NOTE_ATTRIB;
2179 			}
2180 			if (ip->ino_data.uflags & (IMMUTABLE | APPEND)) {
2181 				error = 0;
2182 				goto done;
2183 			}
2184 		}
2185 		goto done;
2186 	}
2187 	if (ip->ino_data.uflags & (IMMUTABLE | APPEND)) {
2188 		error = EPERM;
2189 		goto done;
2190 	}
2191 	if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) {
2192 		mode_t cur_mode = ip->ino_data.mode;
2193 		uid_t cur_uid = hammer_to_unix_xid(&ip->ino_data.uid);
2194 		gid_t cur_gid = hammer_to_unix_xid(&ip->ino_data.gid);
2195 		uuid_t uuid_uid;
2196 		uuid_t uuid_gid;
2197 
2198 		error = vop_helper_chown(ap->a_vp, vap->va_uid, vap->va_gid,
2199 					 ap->a_cred,
2200 					 &cur_uid, &cur_gid, &cur_mode);
2201 		if (error == 0) {
2202 			hammer_guid_to_uuid(&uuid_uid, cur_uid);
2203 			hammer_guid_to_uuid(&uuid_gid, cur_gid);
2204 			if (bcmp(&uuid_uid, &ip->ino_data.uid,
2205 				 sizeof(uuid_uid)) ||
2206 			    bcmp(&uuid_gid, &ip->ino_data.gid,
2207 				 sizeof(uuid_gid)) ||
2208 			    ip->ino_data.mode != cur_mode) {
2209 				ip->ino_data.uid = uuid_uid;
2210 				ip->ino_data.gid = uuid_gid;
2211 				ip->ino_data.mode = cur_mode;
2212 				ip->ino_data.ctime = trans.time;
2213 				modflags |= HAMMER_INODE_DDIRTY;
2214 			}
2215 			kflags |= NOTE_ATTRIB;
2216 		}
2217 	}
2218 	while (vap->va_size != VNOVAL && ip->ino_data.size != vap->va_size) {
2219 		switch(ap->a_vp->v_type) {
2220 		case VREG:
2221 			if (vap->va_size == ip->ino_data.size)
2222 				break;
2223 
2224 			/*
2225 			 * Log the operation if in fast-fsync mode or if
2226 			 * there are unterminated redo write records present.
2227 			 *
2228 			 * The second check is needed so the recovery code
2229 			 * properly truncates write redos even if nominal
2230 			 * REDO operations is turned off due to excessive
2231 			 * writes, because the related records might be
2232 			 * destroyed and never lay down a TERM_WRITE.
2233 			 */
2234 			if ((ip->flags & HAMMER_INODE_REDO) ||
2235 			    (ip->flags & HAMMER_INODE_RDIRTY)) {
2236 				error = hammer_generate_redo(&trans, ip,
2237 							     vap->va_size,
2238 							     HAMMER_REDO_TRUNC,
2239 							     NULL, 0);
2240 			}
2241 			blksize = hammer_blocksize(vap->va_size);
2242 
2243 			/*
2244 			 * XXX break atomicy, we can deadlock the backend
2245 			 * if we do not release the lock.  Probably not a
2246 			 * big deal here.
2247 			 */
2248 			if (vap->va_size < ip->ino_data.size) {
2249 				nvtruncbuf(ap->a_vp, vap->va_size,
2250 					   blksize,
2251 					   hammer_blockoff(vap->va_size),
2252 					   0);
2253 				truncating = 1;
2254 				kflags |= NOTE_WRITE;
2255 			} else {
2256 				nvextendbuf(ap->a_vp,
2257 					    ip->ino_data.size,
2258 					    vap->va_size,
2259 					    hammer_blocksize(ip->ino_data.size),
2260 					    hammer_blocksize(vap->va_size),
2261 					    hammer_blockoff(ip->ino_data.size),
2262 					    hammer_blockoff(vap->va_size),
2263 					    0);
2264 				truncating = 0;
2265 				kflags |= NOTE_WRITE | NOTE_EXTEND;
2266 			}
2267 			ip->ino_data.size = vap->va_size;
2268 			ip->ino_data.mtime = trans.time;
2269 			/* XXX safe to use SDIRTY instead of DDIRTY here? */
2270 			modflags |= HAMMER_INODE_MTIME | HAMMER_INODE_DDIRTY;
2271 
2272 			/*
2273 			 * On-media truncation is cached in the inode until
2274 			 * the inode is synchronized.  We must immediately
2275 			 * handle any frontend records.
2276 			 */
2277 			if (truncating) {
2278 				hammer_ip_frontend_trunc(ip, vap->va_size);
2279 				if ((ip->flags & HAMMER_INODE_TRUNCATED) == 0) {
2280 					ip->flags |= HAMMER_INODE_TRUNCATED;
2281 					ip->trunc_off = vap->va_size;
2282 					hammer_inode_dirty(ip);
2283 				} else if (ip->trunc_off > vap->va_size) {
2284 					ip->trunc_off = vap->va_size;
2285 				}
2286 			}
2287 
2288 #if 0
2289 			/*
2290 			 * When truncating, nvtruncbuf() may have cleaned out
2291 			 * a portion of the last block on-disk in the buffer
2292 			 * cache.  We must clean out any frontend records
2293 			 * for blocks beyond the new last block.
2294 			 */
2295 			aligned_size = (vap->va_size + (blksize - 1)) &
2296 				       ~(int64_t)(blksize - 1);
2297 			if (truncating && vap->va_size < aligned_size) {
2298 				aligned_size -= blksize;
2299 				hammer_ip_frontend_trunc(ip, aligned_size);
2300 			}
2301 #endif
2302 			break;
2303 		case VDATABASE:
2304 			if ((ip->flags & HAMMER_INODE_TRUNCATED) == 0) {
2305 				ip->flags |= HAMMER_INODE_TRUNCATED;
2306 				ip->trunc_off = vap->va_size;
2307 				hammer_inode_dirty(ip);
2308 			} else if (ip->trunc_off > vap->va_size) {
2309 				ip->trunc_off = vap->va_size;
2310 			}
2311 			hammer_ip_frontend_trunc(ip, vap->va_size);
2312 			ip->ino_data.size = vap->va_size;
2313 			ip->ino_data.mtime = trans.time;
2314 			modflags |= HAMMER_INODE_MTIME | HAMMER_INODE_DDIRTY;
2315 			kflags |= NOTE_ATTRIB;
2316 			break;
2317 		default:
2318 			error = EINVAL;
2319 			goto done;
2320 		}
2321 		break;
2322 	}
2323 	if (vap->va_atime.tv_sec != VNOVAL) {
2324 		ip->ino_data.atime = hammer_timespec_to_time(&vap->va_atime);
2325 		modflags |= HAMMER_INODE_ATIME;
2326 		kflags |= NOTE_ATTRIB;
2327 	}
2328 	if (vap->va_mtime.tv_sec != VNOVAL) {
2329 		ip->ino_data.mtime = hammer_timespec_to_time(&vap->va_mtime);
2330 		modflags |= HAMMER_INODE_MTIME;
2331 		kflags |= NOTE_ATTRIB;
2332 	}
2333 	if (vap->va_mode != (mode_t)VNOVAL) {
2334 		mode_t   cur_mode = ip->ino_data.mode;
2335 		uid_t cur_uid = hammer_to_unix_xid(&ip->ino_data.uid);
2336 		gid_t cur_gid = hammer_to_unix_xid(&ip->ino_data.gid);
2337 
2338 		error = vop_helper_chmod(ap->a_vp, vap->va_mode, ap->a_cred,
2339 					 cur_uid, cur_gid, &cur_mode);
2340 		if (error == 0 && ip->ino_data.mode != cur_mode) {
2341 			ip->ino_data.mode = cur_mode;
2342 			ip->ino_data.ctime = trans.time;
2343 			modflags |= HAMMER_INODE_DDIRTY;
2344 			kflags |= NOTE_ATTRIB;
2345 		}
2346 	}
2347 done:
2348 	if (error == 0)
2349 		hammer_modify_inode(&trans, ip, modflags);
2350 	hammer_done_transaction(&trans);
2351 	hammer_knote(ap->a_vp, kflags);
2352 	lwkt_reltoken(&hmp->fs_token);
2353 	return (error);
2354 }
2355 
2356 /*
2357  * hammer_vop_nsymlink { nch, dvp, vpp, cred, vap, target }
2358  */
2359 static
2360 int
2361 hammer_vop_nsymlink(struct vop_nsymlink_args *ap)
2362 {
2363 	struct hammer_transaction trans;
2364 	hammer_inode_t dip;
2365 	hammer_inode_t nip;
2366 	hammer_record_t record;
2367 	struct nchandle *nch;
2368 	hammer_mount_t hmp;
2369 	int error;
2370 	int bytes;
2371 
2372 	ap->a_vap->va_type = VLNK;
2373 
2374 	nch = ap->a_nch;
2375 	dip = VTOI(ap->a_dvp);
2376 	hmp = dip->hmp;
2377 
2378 	if (dip->flags & HAMMER_INODE_RO)
2379 		return (EROFS);
2380 	if ((error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0)
2381 		return (error);
2382 
2383 	/*
2384 	 * Create a transaction to cover the operations we perform.
2385 	 */
2386 	lwkt_gettoken(&hmp->fs_token);
2387 	hammer_start_transaction(&trans, hmp);
2388 
2389 	/*
2390 	 * Create a new filesystem object of the requested type.  The
2391 	 * returned inode will be referenced but not locked.
2392 	 */
2393 
2394 	error = hammer_create_inode(&trans, ap->a_vap, ap->a_cred,
2395 				    dip, nch->ncp->nc_name, nch->ncp->nc_nlen,
2396 				    NULL, &nip);
2397 	if (error) {
2398 		hammer_done_transaction(&trans);
2399 		*ap->a_vpp = NULL;
2400 		lwkt_reltoken(&hmp->fs_token);
2401 		return (error);
2402 	}
2403 
2404 	/*
2405 	 * Add a record representing the symlink.  symlink stores the link
2406 	 * as pure data, not a string, and is no \0 terminated.
2407 	 */
2408 	if (error == 0) {
2409 		bytes = strlen(ap->a_target);
2410 
2411 		if (bytes <= HAMMER_INODE_BASESYMLEN) {
2412 			bcopy(ap->a_target, nip->ino_data.ext.symlink, bytes);
2413 		} else {
2414 			record = hammer_alloc_mem_record(nip, bytes);
2415 			record->type = HAMMER_MEM_RECORD_GENERAL;
2416 
2417 			record->leaf.base.localization = nip->obj_localization |
2418 							 HAMMER_LOCALIZE_MISC;
2419 			record->leaf.base.key = HAMMER_FIXKEY_SYMLINK;
2420 			record->leaf.base.rec_type = HAMMER_RECTYPE_FIX;
2421 			record->leaf.data_len = bytes;
2422 			KKASSERT(HAMMER_SYMLINK_NAME_OFF == 0);
2423 			bcopy(ap->a_target, record->data->symlink.name, bytes);
2424 			error = hammer_ip_add_record(&trans, record);
2425 		}
2426 
2427 		/*
2428 		 * Set the file size to the length of the link.
2429 		 */
2430 		if (error == 0) {
2431 			nip->ino_data.size = bytes;
2432 			hammer_modify_inode(&trans, nip, HAMMER_INODE_DDIRTY);
2433 		}
2434 	}
2435 	if (error == 0)
2436 		error = hammer_ip_add_direntry(&trans, dip, nch->ncp->nc_name,
2437 						nch->ncp->nc_nlen, nip);
2438 
2439 	/*
2440 	 * Finish up.
2441 	 */
2442 	if (error) {
2443 		hammer_rel_inode(nip, 0);
2444 		*ap->a_vpp = NULL;
2445 	} else {
2446 		error = hammer_get_vnode(nip, ap->a_vpp);
2447 		hammer_rel_inode(nip, 0);
2448 		if (error == 0) {
2449 			cache_setunresolved(ap->a_nch);
2450 			cache_setvp(ap->a_nch, *ap->a_vpp);
2451 			hammer_knote(ap->a_dvp, NOTE_WRITE);
2452 		}
2453 	}
2454 	hammer_done_transaction(&trans);
2455 	lwkt_reltoken(&hmp->fs_token);
2456 	return (error);
2457 }
2458 
2459 /*
2460  * hammer_vop_nwhiteout { nch, dvp, cred, flags }
2461  */
2462 static
2463 int
2464 hammer_vop_nwhiteout(struct vop_nwhiteout_args *ap)
2465 {
2466 	struct hammer_transaction trans;
2467 	hammer_inode_t dip;
2468 	hammer_mount_t hmp;
2469 	int error;
2470 
2471 	dip = VTOI(ap->a_dvp);
2472 	hmp = dip->hmp;
2473 
2474 	if (hammer_nohistory(dip) == 0 &&
2475 	    (error = hammer_checkspace(hmp, HAMMER_CHKSPC_CREATE)) != 0) {
2476 		return (error);
2477 	}
2478 
2479 	lwkt_gettoken(&hmp->fs_token);
2480 	hammer_start_transaction(&trans, hmp);
2481 	error = hammer_dounlink(&trans, ap->a_nch, ap->a_dvp,
2482 				ap->a_cred, ap->a_flags, -1);
2483 	hammer_done_transaction(&trans);
2484 	lwkt_reltoken(&hmp->fs_token);
2485 
2486 	return (error);
2487 }
2488 
2489 /*
2490  * hammer_vop_ioctl { vp, command, data, fflag, cred }
2491  */
2492 static
2493 int
2494 hammer_vop_ioctl(struct vop_ioctl_args *ap)
2495 {
2496 	hammer_inode_t ip = ap->a_vp->v_data;
2497 	hammer_mount_t hmp = ip->hmp;
2498 	int error;
2499 
2500 	lwkt_gettoken(&hmp->fs_token);
2501 	error = hammer_ioctl(ip, ap->a_command, ap->a_data,
2502 			     ap->a_fflag, ap->a_cred);
2503 	lwkt_reltoken(&hmp->fs_token);
2504 	return (error);
2505 }
2506 
2507 static
2508 int
2509 hammer_vop_mountctl(struct vop_mountctl_args *ap)
2510 {
2511 	static const struct mountctl_opt extraopt[] = {
2512 		{ HMNT_NOHISTORY,	"nohistory" },
2513 		{ HMNT_MASTERID,	"master" },
2514 		{ HMNT_NOMIRROR,	"nomirror" },
2515 		{ 0, NULL}
2516 
2517 	};
2518 	hammer_mount_t hmp;
2519 	struct mount *mp;
2520 	int usedbytes;
2521 	int error;
2522 
2523 	error = 0;
2524 	usedbytes = 0;
2525 	mp = ap->a_head.a_ops->head.vv_mount;
2526 	KKASSERT(mp->mnt_data != NULL);
2527 	hmp = (hammer_mount_t)mp->mnt_data;
2528 
2529 	lwkt_gettoken(&hmp->fs_token);
2530 
2531 	switch(ap->a_op) {
2532 	case MOUNTCTL_SET_EXPORT:
2533 		if (ap->a_ctllen != sizeof(struct export_args))
2534 			error = EINVAL;
2535 		else
2536 			error = hammer_vfs_export(mp, ap->a_op,
2537 				      (const struct export_args *)ap->a_ctl);
2538 		break;
2539 	case MOUNTCTL_MOUNTFLAGS:
2540 		/*
2541 		 * Call standard mountctl VOP function
2542 		 * so we get user mount flags.
2543 		 */
2544 		error = vop_stdmountctl(ap);
2545 		if (error)
2546 			break;
2547 
2548 		usedbytes = *ap->a_res;
2549 
2550 		if (usedbytes > 0 && usedbytes < ap->a_buflen) {
2551 			usedbytes += vfs_flagstostr(hmp->hflags, extraopt,
2552 						    ap->a_buf,
2553 						    ap->a_buflen - usedbytes,
2554 						    &error);
2555 		}
2556 
2557 		*ap->a_res += usedbytes;
2558 		break;
2559 	default:
2560 		error = vop_stdmountctl(ap);
2561 		break;
2562 	}
2563 	lwkt_reltoken(&hmp->fs_token);
2564 	return(error);
2565 }
2566 
2567 /*
2568  * hammer_vop_strategy { vp, bio }
2569  *
2570  * Strategy call, used for regular file read & write only.  Note that the
2571  * bp may represent a cluster.
2572  *
2573  * To simplify operation and allow better optimizations in the future,
2574  * this code does not make any assumptions with regards to buffer alignment
2575  * or size.
2576  */
2577 static
2578 int
2579 hammer_vop_strategy(struct vop_strategy_args *ap)
2580 {
2581 	struct buf *bp;
2582 	int error;
2583 
2584 	bp = ap->a_bio->bio_buf;
2585 
2586 	switch(bp->b_cmd) {
2587 	case BUF_CMD_READ:
2588 		error = hammer_vop_strategy_read(ap);
2589 		break;
2590 	case BUF_CMD_WRITE:
2591 		error = hammer_vop_strategy_write(ap);
2592 		break;
2593 	default:
2594 		bp->b_error = error = EINVAL;
2595 		bp->b_flags |= B_ERROR;
2596 		biodone(ap->a_bio);
2597 		break;
2598 	}
2599 
2600 	/* hammer_dump_dedup_cache(((hammer_inode_t)ap->a_vp->v_data)->hmp); */
2601 
2602 	return (error);
2603 }
2604 
2605 /*
2606  * Read from a regular file.  Iterate the related records and fill in the
2607  * BIO/BUF.  Gaps are zero-filled.
2608  *
2609  * The support code in hammer_object.c should be used to deal with mixed
2610  * in-memory and on-disk records.
2611  *
2612  * NOTE: Can be called from the cluster code with an oversized buf.
2613  *
2614  * XXX atime update
2615  */
2616 static
2617 int
2618 hammer_vop_strategy_read(struct vop_strategy_args *ap)
2619 {
2620 	struct hammer_transaction trans;
2621 	hammer_inode_t ip;
2622 	hammer_inode_t dip;
2623 	hammer_mount_t hmp;
2624 	struct hammer_cursor cursor;
2625 	hammer_base_elm_t base;
2626 	hammer_off_t disk_offset;
2627 	struct bio *bio;
2628 	struct bio *nbio;
2629 	struct buf *bp;
2630 	int64_t rec_offset;
2631 	int64_t ran_end;
2632 	int64_t tmp64;
2633 	int error;
2634 	int boff;
2635 	int roff;
2636 	int n;
2637 	int isdedupable;
2638 
2639 	bio = ap->a_bio;
2640 	bp = bio->bio_buf;
2641 	ip = ap->a_vp->v_data;
2642 	hmp = ip->hmp;
2643 
2644 	/*
2645 	 * The zone-2 disk offset may have been set by the cluster code via
2646 	 * a BMAP operation, or else should be NOOFFSET.
2647 	 *
2648 	 * Checking the high bits for a match against zone-2 should suffice.
2649 	 *
2650 	 * In cases where a lot of data duplication is present it may be
2651 	 * more beneficial to drop through and doubule-buffer through the
2652 	 * device.
2653 	 */
2654 	nbio = push_bio(bio);
2655 	if (hammer_is_zone_large_data(nbio->bio_offset)) {
2656 		if (hammer_double_buffer == 0) {
2657 			lwkt_gettoken(&hmp->fs_token);
2658 			error = hammer_io_direct_read(hmp, nbio, NULL);
2659 			lwkt_reltoken(&hmp->fs_token);
2660 			return (error);
2661 		}
2662 
2663 		/*
2664 		 * Try to shortcut requests for double_buffer mode too.
2665 		 * Since this mode runs through the device buffer cache
2666 		 * only compatible buffer sizes (meaning those generated
2667 		 * by normal filesystem buffers) are legal.
2668 		 */
2669 		if (hammer_live_dedup == 0 && (bp->b_flags & B_PAGING) == 0) {
2670 			lwkt_gettoken(&hmp->fs_token);
2671 			error = hammer_io_indirect_read(hmp, nbio, NULL);
2672 			lwkt_reltoken(&hmp->fs_token);
2673 			return (error);
2674 		}
2675 	}
2676 
2677 	/*
2678 	 * Well, that sucked.  Do it the hard way.  If all the stars are
2679 	 * aligned we may still be able to issue a direct-read.
2680 	 */
2681 	lwkt_gettoken(&hmp->fs_token);
2682 	hammer_simple_transaction(&trans, hmp);
2683 	hammer_init_cursor(&trans, &cursor, &ip->cache[1], ip);
2684 
2685 	/*
2686 	 * Key range (begin and end inclusive) to scan.  Note that the key's
2687 	 * stored in the actual records represent BASE+LEN, not BASE.  The
2688 	 * first record containing bio_offset will have a key > bio_offset.
2689 	 */
2690 	cursor.key_beg.localization = ip->obj_localization |
2691 				      HAMMER_LOCALIZE_MISC;
2692 	cursor.key_beg.obj_id = ip->obj_id;
2693 	cursor.key_beg.create_tid = 0;
2694 	cursor.key_beg.delete_tid = 0;
2695 	cursor.key_beg.obj_type = 0;
2696 	cursor.key_beg.key = bio->bio_offset + 1;
2697 	cursor.asof = ip->obj_asof;
2698 	cursor.flags |= HAMMER_CURSOR_ASOF;
2699 
2700 	cursor.key_end = cursor.key_beg;
2701 	KKASSERT(ip->ino_data.obj_type == HAMMER_OBJTYPE_REGFILE);
2702 #if 0
2703 	if (ip->ino_data.obj_type == HAMMER_OBJTYPE_DBFILE) {
2704 		cursor.key_beg.rec_type = HAMMER_RECTYPE_DB;
2705 		cursor.key_end.rec_type = HAMMER_RECTYPE_DB;
2706 		cursor.key_end.key = HAMMER_MAX_KEY;
2707 	} else
2708 #endif
2709 	{
2710 		ran_end = bio->bio_offset + bp->b_bufsize;
2711 		cursor.key_beg.rec_type = HAMMER_RECTYPE_DATA;
2712 		cursor.key_end.rec_type = HAMMER_RECTYPE_DATA;
2713 		tmp64 = ran_end + MAXPHYS + 1;	/* work-around GCC-4 bug */
2714 		if (tmp64 < ran_end)
2715 			cursor.key_end.key = HAMMER_MAX_KEY;
2716 		else
2717 			cursor.key_end.key = ran_end + MAXPHYS + 1;
2718 	}
2719 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE;
2720 
2721 	/*
2722 	 * Set NOSWAPCACHE for cursor data extraction if double buffering
2723 	 * is disabled or (if the file is not marked cacheable via chflags
2724 	 * and vm.swapcache_use_chflags is enabled).
2725 	 */
2726 	if (hammer_double_buffer == 0 ||
2727 	    ((ap->a_vp->v_flag & VSWAPCACHE) == 0 &&
2728 	     vm_swapcache_use_chflags)) {
2729 		cursor.flags |= HAMMER_CURSOR_NOSWAPCACHE;
2730 	}
2731 
2732 	error = hammer_ip_first(&cursor);
2733 	boff = 0;
2734 
2735 	while (error == 0) {
2736 		/*
2737 		 * Get the base file offset of the record.  The key for
2738 		 * data records is (base + bytes) rather then (base).
2739 		 */
2740 		base = &cursor.leaf->base;
2741 		rec_offset = base->key - cursor.leaf->data_len;
2742 
2743 		/*
2744 		 * Calculate the gap, if any, and zero-fill it.
2745 		 *
2746 		 * n is the offset of the start of the record verses our
2747 		 * current seek offset in the bio.
2748 		 */
2749 		n = (int)(rec_offset - (bio->bio_offset + boff));
2750 		if (n > 0) {
2751 			if (n > bp->b_bufsize - boff)
2752 				n = bp->b_bufsize - boff;
2753 			bzero((char *)bp->b_data + boff, n);
2754 			boff += n;
2755 			n = 0;
2756 		}
2757 
2758 		/*
2759 		 * Calculate the data offset in the record and the number
2760 		 * of bytes we can copy.
2761 		 *
2762 		 * There are two degenerate cases.  First, boff may already
2763 		 * be at bp->b_bufsize.  Secondly, the data offset within
2764 		 * the record may exceed the record's size.
2765 		 */
2766 		roff = -n;
2767 		rec_offset += roff;
2768 		n = cursor.leaf->data_len - roff;
2769 		if (n <= 0) {
2770 			hdkprintf("bad n=%d roff=%d\n", n, roff);
2771 			n = 0;
2772 		} else if (n > bp->b_bufsize - boff) {
2773 			n = bp->b_bufsize - boff;
2774 		}
2775 
2776 		/*
2777 		 * Deal with cached truncations.  This cool bit of code
2778 		 * allows truncate()/ftruncate() to avoid having to sync
2779 		 * the file.
2780 		 *
2781 		 * If the frontend is truncated then all backend records are
2782 		 * subject to the frontend's truncation.
2783 		 *
2784 		 * If the backend is truncated then backend records on-disk
2785 		 * (but not in-memory) are subject to the backend's
2786 		 * truncation.  In-memory records owned by the backend
2787 		 * represent data written after the truncation point on the
2788 		 * backend and must not be truncated.
2789 		 *
2790 		 * Truncate operations deal with frontend buffer cache
2791 		 * buffers and frontend-owned in-memory records synchronously.
2792 		 */
2793 		if (ip->flags & HAMMER_INODE_TRUNCATED) {
2794 			if (hammer_cursor_ondisk(&cursor)/* ||
2795 			    cursor.iprec->flush_state == HAMMER_FST_FLUSH*/) {
2796 				if (ip->trunc_off <= rec_offset)
2797 					n = 0;
2798 				else if (ip->trunc_off < rec_offset + n)
2799 					n = (int)(ip->trunc_off - rec_offset);
2800 			}
2801 		}
2802 		if (ip->sync_flags & HAMMER_INODE_TRUNCATED) {
2803 			if (hammer_cursor_ondisk(&cursor)) {
2804 				if (ip->sync_trunc_off <= rec_offset)
2805 					n = 0;
2806 				else if (ip->sync_trunc_off < rec_offset + n)
2807 					n = (int)(ip->sync_trunc_off - rec_offset);
2808 			}
2809 		}
2810 
2811 		/*
2812 		 * Try to issue a direct read into our bio if possible,
2813 		 * otherwise resolve the element data into a hammer_buffer
2814 		 * and copy.
2815 		 *
2816 		 * The buffer on-disk should be zerod past any real
2817 		 * truncation point, but may not be for any synthesized
2818 		 * truncation point from above.
2819 		 *
2820 		 * NOTE: disk_offset is only valid if the cursor data is
2821 		 *	 on-disk.
2822 		 */
2823 		disk_offset = cursor.leaf->data_offset + roff;
2824 		isdedupable = (boff == 0 && n == bp->b_bufsize &&
2825 			       hammer_cursor_ondisk(&cursor) &&
2826 			       ((int)disk_offset & HAMMER_BUFMASK) == 0);
2827 
2828 		if (isdedupable && hammer_double_buffer == 0) {
2829 			/*
2830 			 * Direct read case
2831 			 */
2832 			KKASSERT(hammer_is_zone_large_data(disk_offset));
2833 			nbio->bio_offset = disk_offset;
2834 			error = hammer_io_direct_read(hmp, nbio, cursor.leaf);
2835 			if (hammer_live_dedup && error == 0)
2836 				hammer_dedup_cache_add(ip, cursor.leaf);
2837 			goto done;
2838 		} else if (isdedupable) {
2839 			/*
2840 			 * Async I/O case for reading from backing store
2841 			 * and copying the data to the filesystem buffer.
2842 			 * live-dedup has to verify the data anyway if it
2843 			 * gets a hit later so we can just add the entry
2844 			 * now.
2845 			 */
2846 			KKASSERT(hammer_is_zone_large_data(disk_offset));
2847 			nbio->bio_offset = disk_offset;
2848 			if (hammer_live_dedup)
2849 				hammer_dedup_cache_add(ip, cursor.leaf);
2850 			error = hammer_io_indirect_read(hmp, nbio, cursor.leaf);
2851 			goto done;
2852 		} else if (n) {
2853 			error = hammer_ip_resolve_data(&cursor);
2854 			if (error == 0) {
2855 				if (hammer_live_dedup && isdedupable)
2856 					hammer_dedup_cache_add(ip, cursor.leaf);
2857 				bcopy((char *)cursor.data + roff,
2858 				      (char *)bp->b_data + boff, n);
2859 			}
2860 		}
2861 		if (error)
2862 			break;
2863 
2864 		/*
2865 		 * We have to be sure that the only elements added to the
2866 		 * dedup cache are those which are already on-media.
2867 		 */
2868 		if (hammer_live_dedup && hammer_cursor_ondisk(&cursor))
2869 			hammer_dedup_cache_add(ip, cursor.leaf);
2870 
2871 		/*
2872 		 * Iterate until we have filled the request.
2873 		 */
2874 		boff += n;
2875 		if (boff == bp->b_bufsize)
2876 			break;
2877 		error = hammer_ip_next(&cursor);
2878 	}
2879 
2880 	/*
2881 	 * There may have been a gap after the last record
2882 	 */
2883 	if (error == ENOENT)
2884 		error = 0;
2885 	if (error == 0 && boff != bp->b_bufsize) {
2886 		KKASSERT(boff < bp->b_bufsize);
2887 		bzero((char *)bp->b_data + boff, bp->b_bufsize - boff);
2888 		/* boff = bp->b_bufsize; */
2889 	}
2890 
2891 	/*
2892 	 * Disallow swapcache operation on the vnode buffer if double
2893 	 * buffering is enabled, the swapcache will get the data via
2894 	 * the block device buffer.
2895 	 */
2896 	if (hammer_double_buffer)
2897 		bp->b_flags |= B_NOTMETA;
2898 
2899 	/*
2900 	 * Cleanup
2901 	 */
2902 	bp->b_resid = 0;
2903 	bp->b_error = error;
2904 	if (error)
2905 		bp->b_flags |= B_ERROR;
2906 	biodone(ap->a_bio);
2907 
2908 done:
2909 	/*
2910 	 * Cache the b-tree node for the last data read in cache[1].
2911 	 *
2912 	 * If we hit the file EOF then also cache the node in the
2913 	 * governing directory's cache[3], it will be used to initialize
2914 	 * the new inode's cache[1] for any inodes looked up via the directory.
2915 	 *
2916 	 * This doesn't reduce disk accesses since the B-Tree chain is
2917 	 * likely cached, but it does reduce cpu overhead when looking
2918 	 * up file offsets for cpdup/tar/cpio style iterations.
2919 	 */
2920 	if (cursor.node)
2921 		hammer_cache_node(&ip->cache[1], cursor.node);
2922 	if (ran_end >= ip->ino_data.size) {
2923 		dip = hammer_find_inode(&trans, ip->ino_data.parent_obj_id,
2924 					ip->obj_asof, ip->obj_localization);
2925 		if (dip) {
2926 			hammer_cache_node(&dip->cache[3], cursor.node);
2927 			hammer_rel_inode(dip, 0);
2928 		}
2929 	}
2930 	hammer_done_cursor(&cursor);
2931 	hammer_done_transaction(&trans);
2932 	lwkt_reltoken(&hmp->fs_token);
2933 	return(error);
2934 }
2935 
2936 /*
2937  * BMAP operation - used to support cluster_read() only.
2938  *
2939  * (struct vnode *vp, off_t loffset, off_t *doffsetp, int *runp, int *runb)
2940  *
2941  * This routine may return EOPNOTSUPP if the opration is not supported for
2942  * the specified offset.  The contents of the pointer arguments do not
2943  * need to be initialized in that case.
2944  *
2945  * If a disk address is available and properly aligned return 0 with
2946  * *doffsetp set to the zone-2 address, and *runp / *runb set appropriately
2947  * to the run-length relative to that offset.  Callers may assume that
2948  * *doffsetp is valid if 0 is returned, even if *runp is not sufficiently
2949  * large, so return EOPNOTSUPP if it is not sufficiently large.
2950  */
2951 static
2952 int
2953 hammer_vop_bmap(struct vop_bmap_args *ap)
2954 {
2955 	struct hammer_transaction trans;
2956 	hammer_inode_t ip;
2957 	hammer_mount_t hmp;
2958 	struct hammer_cursor cursor;
2959 	hammer_base_elm_t base;
2960 	int64_t rec_offset;
2961 	int64_t ran_end;
2962 	int64_t tmp64;
2963 	int64_t base_offset;
2964 	int64_t base_disk_offset;
2965 	int64_t last_offset;
2966 	hammer_off_t last_disk_offset;
2967 	hammer_off_t disk_offset;
2968 	int	rec_len;
2969 	int	error;
2970 	int	blksize;
2971 
2972 	ip = ap->a_vp->v_data;
2973 	hmp = ip->hmp;
2974 
2975 	/*
2976 	 * We can only BMAP regular files.  We can't BMAP database files,
2977 	 * directories, etc.
2978 	 */
2979 	if (ip->ino_data.obj_type != HAMMER_OBJTYPE_REGFILE)
2980 		return(EOPNOTSUPP);
2981 
2982 	/*
2983 	 * bmap is typically called with runp/runb both NULL when used
2984 	 * for writing.  We do not support BMAP for writing atm.
2985 	 */
2986 	if (ap->a_cmd != BUF_CMD_READ)
2987 		return(EOPNOTSUPP);
2988 
2989 	/*
2990 	 * Scan the B-Tree to acquire blockmap addresses, then translate
2991 	 * to raw addresses.
2992 	 */
2993 	lwkt_gettoken(&hmp->fs_token);
2994 	hammer_simple_transaction(&trans, hmp);
2995 
2996 	hammer_init_cursor(&trans, &cursor, &ip->cache[1], ip);
2997 
2998 	/*
2999 	 * Key range (begin and end inclusive) to scan.  Note that the key's
3000 	 * stored in the actual records represent BASE+LEN, not BASE.  The
3001 	 * first record containing bio_offset will have a key > bio_offset.
3002 	 */
3003 	cursor.key_beg.localization = ip->obj_localization |
3004 				      HAMMER_LOCALIZE_MISC;
3005 	cursor.key_beg.obj_id = ip->obj_id;
3006 	cursor.key_beg.create_tid = 0;
3007 	cursor.key_beg.delete_tid = 0;
3008 	cursor.key_beg.obj_type = 0;
3009 	if (ap->a_runb)
3010 		cursor.key_beg.key = ap->a_loffset - MAXPHYS + 1;
3011 	else
3012 		cursor.key_beg.key = ap->a_loffset + 1;
3013 	if (cursor.key_beg.key < 0)
3014 		cursor.key_beg.key = 0;
3015 	cursor.asof = ip->obj_asof;
3016 	cursor.flags |= HAMMER_CURSOR_ASOF;
3017 
3018 	cursor.key_end = cursor.key_beg;
3019 	KKASSERT(ip->ino_data.obj_type == HAMMER_OBJTYPE_REGFILE);
3020 
3021 	ran_end = ap->a_loffset + MAXPHYS;
3022 	cursor.key_beg.rec_type = HAMMER_RECTYPE_DATA;
3023 	cursor.key_end.rec_type = HAMMER_RECTYPE_DATA;
3024 	tmp64 = ran_end + MAXPHYS + 1;	/* work-around GCC-4 bug */
3025 	if (tmp64 < ran_end)
3026 		cursor.key_end.key = HAMMER_MAX_KEY;
3027 	else
3028 		cursor.key_end.key = ran_end + MAXPHYS + 1;
3029 
3030 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE;
3031 
3032 	error = hammer_ip_first(&cursor);
3033 	base_offset = last_offset = 0;
3034 	base_disk_offset = last_disk_offset = 0;
3035 
3036 	while (error == 0) {
3037 		/*
3038 		 * Get the base file offset of the record.  The key for
3039 		 * data records is (base + bytes) rather then (base).
3040 		 *
3041 		 * NOTE: rec_offset + rec_len may exceed the end-of-file.
3042 		 * The extra bytes should be zero on-disk and the BMAP op
3043 		 * should still be ok.
3044 		 */
3045 		base = &cursor.leaf->base;
3046 		rec_offset = base->key - cursor.leaf->data_len;
3047 		rec_len    = cursor.leaf->data_len;
3048 
3049 		/*
3050 		 * Incorporate any cached truncation.
3051 		 *
3052 		 * NOTE: Modifications to rec_len based on synthesized
3053 		 * truncation points remove the guarantee that any extended
3054 		 * data on disk is zero (since the truncations may not have
3055 		 * taken place on-media yet).
3056 		 */
3057 		if (ip->flags & HAMMER_INODE_TRUNCATED) {
3058 			if (hammer_cursor_ondisk(&cursor) ||
3059 			    cursor.iprec->flush_state == HAMMER_FST_FLUSH) {
3060 				if (ip->trunc_off <= rec_offset)
3061 					rec_len = 0;
3062 				else if (ip->trunc_off < rec_offset + rec_len)
3063 					rec_len = (int)(ip->trunc_off - rec_offset);
3064 			}
3065 		}
3066 		if (ip->sync_flags & HAMMER_INODE_TRUNCATED) {
3067 			if (hammer_cursor_ondisk(&cursor)) {
3068 				if (ip->sync_trunc_off <= rec_offset)
3069 					rec_len = 0;
3070 				else if (ip->sync_trunc_off < rec_offset + rec_len)
3071 					rec_len = (int)(ip->sync_trunc_off - rec_offset);
3072 			}
3073 		}
3074 
3075 		/*
3076 		 * Accumulate information.  If we have hit a discontiguous
3077 		 * block reset base_offset unless we are already beyond the
3078 		 * requested offset.  If we are, that's it, we stop.
3079 		 */
3080 		if (error)
3081 			break;
3082 		if (hammer_cursor_ondisk(&cursor)) {
3083 			disk_offset = cursor.leaf->data_offset;
3084 			if (rec_offset != last_offset ||
3085 			    disk_offset != last_disk_offset) {
3086 				if (rec_offset > ap->a_loffset)
3087 					break;
3088 				base_offset = rec_offset;
3089 				base_disk_offset = disk_offset;
3090 			}
3091 			last_offset = rec_offset + rec_len;
3092 			last_disk_offset = disk_offset + rec_len;
3093 
3094 			if (hammer_live_dedup)
3095 				hammer_dedup_cache_add(ip, cursor.leaf);
3096 		}
3097 
3098 		error = hammer_ip_next(&cursor);
3099 	}
3100 
3101 	if (cursor.node)
3102 		hammer_cache_node(&ip->cache[1], cursor.node);
3103 
3104 	hammer_done_cursor(&cursor);
3105 	hammer_done_transaction(&trans);
3106 	lwkt_reltoken(&hmp->fs_token);
3107 
3108 	/*
3109 	 * If we couldn't find any records or the records we did find were
3110 	 * all behind the requested offset, return failure.  A forward
3111 	 * truncation can leave a hole w/ no on-disk records.
3112 	 */
3113 	if (last_offset == 0 || last_offset < ap->a_loffset)
3114 		return (EOPNOTSUPP);
3115 
3116 	/*
3117 	 * Figure out the block size at the requested offset and adjust
3118 	 * our limits so the cluster_read() does not create inappropriately
3119 	 * sized buffer cache buffers.
3120 	 */
3121 	blksize = hammer_blocksize(ap->a_loffset);
3122 	if (hammer_blocksize(base_offset) != blksize) {
3123 		base_offset = hammer_blockdemarc(base_offset, ap->a_loffset);
3124 	}
3125 	if (last_offset != ap->a_loffset &&
3126 	    hammer_blocksize(last_offset - 1) != blksize) {
3127 		last_offset = hammer_blockdemarc(ap->a_loffset,
3128 						 last_offset - 1);
3129 	}
3130 
3131 	/*
3132 	 * Returning EOPNOTSUPP simply prevents the direct-IO optimization
3133 	 * from occuring.
3134 	 */
3135 	disk_offset = base_disk_offset + (ap->a_loffset - base_offset);
3136 
3137 	if (!hammer_is_zone_large_data(disk_offset)) {
3138 		/*
3139 		 * Only large-data zones can be direct-IOd
3140 		 */
3141 		error = EOPNOTSUPP;
3142 	} else if ((disk_offset & HAMMER_BUFMASK) ||
3143 		   (last_offset - ap->a_loffset) < blksize) {
3144 		/*
3145 		 * doffsetp is not aligned or the forward run size does
3146 		 * not cover a whole buffer, disallow the direct I/O.
3147 		 */
3148 		error = EOPNOTSUPP;
3149 	} else {
3150 		/*
3151 		 * We're good.
3152 		 */
3153 		*ap->a_doffsetp = disk_offset;
3154 		if (ap->a_runb) {
3155 			*ap->a_runb = ap->a_loffset - base_offset;
3156 			KKASSERT(*ap->a_runb >= 0);
3157 		}
3158 		if (ap->a_runp) {
3159 			*ap->a_runp = last_offset - ap->a_loffset;
3160 			KKASSERT(*ap->a_runp >= 0);
3161 		}
3162 		error = 0;
3163 	}
3164 	return(error);
3165 }
3166 
3167 /*
3168  * Write to a regular file.   Because this is a strategy call the OS is
3169  * trying to actually get data onto the media.
3170  */
3171 static
3172 int
3173 hammer_vop_strategy_write(struct vop_strategy_args *ap)
3174 {
3175 	hammer_record_t record;
3176 	hammer_mount_t hmp;
3177 	hammer_inode_t ip;
3178 	struct bio *bio;
3179 	struct buf *bp;
3180 	int blksize __debugvar;
3181 	int bytes;
3182 	int error;
3183 
3184 	bio = ap->a_bio;
3185 	bp = bio->bio_buf;
3186 	ip = ap->a_vp->v_data;
3187 	hmp = ip->hmp;
3188 
3189 	blksize = hammer_blocksize(bio->bio_offset);
3190 	KKASSERT(bp->b_bufsize == blksize);
3191 
3192 	if (ip->flags & HAMMER_INODE_RO) {
3193 		bp->b_error = EROFS;
3194 		bp->b_flags |= B_ERROR;
3195 		biodone(ap->a_bio);
3196 		return(EROFS);
3197 	}
3198 
3199 	lwkt_gettoken(&hmp->fs_token);
3200 
3201 	/*
3202 	 * Disallow swapcache operation on the vnode buffer if double
3203 	 * buffering is enabled, the swapcache will get the data via
3204 	 * the block device buffer.
3205 	 */
3206 	if (hammer_double_buffer)
3207 		bp->b_flags |= B_NOTMETA;
3208 
3209 	/*
3210 	 * Interlock with inode destruction (no in-kernel or directory
3211 	 * topology visibility).  If we queue new IO while trying to
3212 	 * destroy the inode we can deadlock the vtrunc call in
3213 	 * hammer_inode_unloadable_check().
3214 	 *
3215 	 * Besides, there's no point flushing a bp associated with an
3216 	 * inode that is being destroyed on-media and has no kernel
3217 	 * references.
3218 	 */
3219 	if ((ip->flags | ip->sync_flags) &
3220 	    (HAMMER_INODE_DELETING|HAMMER_INODE_DELETED)) {
3221 		bp->b_resid = 0;
3222 		biodone(ap->a_bio);
3223 		lwkt_reltoken(&hmp->fs_token);
3224 		return(0);
3225 	}
3226 
3227 	/*
3228 	 * Reserve space and issue a direct-write from the front-end.
3229 	 * NOTE: The direct_io code will hammer_bread/bcopy smaller
3230 	 * allocations.
3231 	 *
3232 	 * An in-memory record will be installed to reference the storage
3233 	 * until the flusher can get to it.
3234 	 *
3235 	 * Since we own the high level bio the front-end will not try to
3236 	 * do a direct-read until the write completes.
3237 	 *
3238 	 * NOTE: The only time we do not reserve a full-sized buffers
3239 	 * worth of data is if the file is small.  We do not try to
3240 	 * allocate a fragment (from the small-data zone) at the end of
3241 	 * an otherwise large file as this can lead to wildly separated
3242 	 * data.
3243 	 */
3244 	KKASSERT((bio->bio_offset & HAMMER_BUFMASK) == 0);
3245 	KKASSERT(bio->bio_offset < ip->ino_data.size);
3246 	if (bio->bio_offset || ip->ino_data.size > HAMMER_HBUFSIZE)
3247 		bytes = bp->b_bufsize;
3248 	else
3249 		bytes = HAMMER_DATA_DOALIGN_WITH(int, ip->ino_data.size);
3250 
3251 	record = hammer_ip_add_bulk(ip, bio->bio_offset, bp->b_data,
3252 				    bytes, &error);
3253 
3254 	/*
3255 	 * B_VFSFLAG1 indicates that a REDO_WRITE entry was generated
3256 	 * in hammer_vop_write().  We must flag the record so the proper
3257 	 * REDO_TERM_WRITE entry is generated during the flush.
3258 	 */
3259 	if (record) {
3260 		if (bp->b_flags & B_VFSFLAG1) {
3261 			record->flags |= HAMMER_RECF_REDO;
3262 			bp->b_flags &= ~B_VFSFLAG1;
3263 		}
3264 		if (record->flags & HAMMER_RECF_DEDUPED) {
3265 			bp->b_resid = 0;
3266 			hammer_ip_replace_bulk(hmp, record);
3267 			biodone(ap->a_bio);
3268 		} else {
3269 			hammer_io_direct_write(hmp, bio, record);
3270 		}
3271 		if (ip->rsv_recs > 1 && hmp->rsv_recs > hammer_limit_recs)
3272 			hammer_flush_inode(ip, 0);
3273 	} else {
3274 		bp->b_bio2.bio_offset = NOOFFSET;
3275 		bp->b_error = error;
3276 		bp->b_flags |= B_ERROR;
3277 		biodone(ap->a_bio);
3278 	}
3279 	lwkt_reltoken(&hmp->fs_token);
3280 	return(error);
3281 }
3282 
3283 /*
3284  * dounlink - disconnect a directory entry
3285  *
3286  * XXX whiteout support not really in yet
3287  */
3288 static int
3289 hammer_dounlink(hammer_transaction_t trans, struct nchandle *nch,
3290 		struct vnode *dvp, struct ucred *cred,
3291 		int flags, int isdir)
3292 {
3293 	struct namecache *ncp;
3294 	hammer_inode_t dip;
3295 	hammer_inode_t ip;
3296 	hammer_mount_t hmp;
3297 	struct hammer_cursor cursor;
3298 	int64_t namekey;
3299 	uint32_t max_iterations;
3300 	int nlen, error;
3301 
3302 	/*
3303 	 * Calculate the namekey and setup the key range for the scan.  This
3304 	 * works kinda like a chained hash table where the lower 32 bits
3305 	 * of the namekey synthesize the chain.
3306 	 *
3307 	 * The key range is inclusive of both key_beg and key_end.
3308 	 */
3309 	dip = VTOI(dvp);
3310 	ncp = nch->ncp;
3311 	hmp = dip->hmp;
3312 
3313 	if (dip->flags & HAMMER_INODE_RO)
3314 		return (EROFS);
3315 
3316 	namekey = hammer_direntry_namekey(dip, ncp->nc_name, ncp->nc_nlen,
3317 					   &max_iterations);
3318 retry:
3319 	hammer_init_cursor(trans, &cursor, &dip->cache[1], dip);
3320 	cursor.key_beg.localization = dip->obj_localization |
3321 				      hammer_dir_localization(dip);
3322         cursor.key_beg.obj_id = dip->obj_id;
3323 	cursor.key_beg.key = namekey;
3324         cursor.key_beg.create_tid = 0;
3325         cursor.key_beg.delete_tid = 0;
3326         cursor.key_beg.rec_type = HAMMER_RECTYPE_DIRENTRY;
3327         cursor.key_beg.obj_type = 0;
3328 
3329 	cursor.key_end = cursor.key_beg;
3330 	cursor.key_end.key += max_iterations;
3331 	cursor.asof = dip->obj_asof;
3332 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE | HAMMER_CURSOR_ASOF;
3333 
3334 	/*
3335 	 * Scan all matching records (the chain), locate the one matching
3336 	 * the requested path component.  info->last_error contains the
3337 	 * error code on search termination and could be 0, ENOENT, or
3338 	 * something else.
3339 	 *
3340 	 * The hammer_ip_*() functions merge in-memory records with on-disk
3341 	 * records for the purposes of the search.
3342 	 */
3343 	error = hammer_ip_first(&cursor);
3344 
3345 	while (error == 0) {
3346 		error = hammer_ip_resolve_data(&cursor);
3347 		if (error)
3348 			break;
3349 		nlen = cursor.leaf->data_len - HAMMER_ENTRY_NAME_OFF;
3350 		KKASSERT(nlen > 0);
3351 		if (ncp->nc_nlen == nlen &&
3352 		    bcmp(ncp->nc_name, cursor.data->entry.name, nlen) == 0) {
3353 			break;
3354 		}
3355 		error = hammer_ip_next(&cursor);
3356 	}
3357 
3358 	/*
3359 	 * If all is ok we have to get the inode so we can adjust nlinks.
3360 	 * To avoid a deadlock with the flusher we must release the inode
3361 	 * lock on the directory when acquiring the inode for the entry.
3362 	 *
3363 	 * If the target is a directory, it must be empty.
3364 	 */
3365 	if (error == 0) {
3366 		hammer_unlock(&cursor.ip->lock);
3367 		ip = hammer_get_inode(trans, dip, cursor.data->entry.obj_id,
3368 				      hmp->asof,
3369 				      cursor.data->entry.localization,
3370 				      0, &error);
3371 		hammer_lock_sh(&cursor.ip->lock);
3372 		if (error == ENOENT) {
3373 			hkprintf("WARNING: Removing dirent w/missing inode "
3374 				"\"%s\"\n"
3375 				"\tobj_id = %016jx\n",
3376 				ncp->nc_name,
3377 				(intmax_t)cursor.data->entry.obj_id);
3378 			error = 0;
3379 		}
3380 
3381 		/*
3382 		 * If isdir >= 0 we validate that the entry is or is not a
3383 		 * directory.  If isdir < 0 we don't care.
3384 		 */
3385 		if (error == 0 && isdir >= 0 && ip) {
3386 			if (isdir &&
3387 			    ip->ino_data.obj_type != HAMMER_OBJTYPE_DIRECTORY) {
3388 				error = ENOTDIR;
3389 			} else if (isdir == 0 &&
3390 			    ip->ino_data.obj_type == HAMMER_OBJTYPE_DIRECTORY) {
3391 				error = EISDIR;
3392 			}
3393 		}
3394 
3395 		/*
3396 		 * If we are trying to remove a directory the directory must
3397 		 * be empty.
3398 		 *
3399 		 * The check directory code can loop and deadlock/retry.  Our
3400 		 * own cursor's node locks must be released to avoid a 3-way
3401 		 * deadlock with the flusher if the check directory code
3402 		 * blocks.
3403 		 *
3404 		 * If any changes whatsoever have been made to the cursor
3405 		 * set EDEADLK and retry.
3406 		 *
3407 		 * WARNING: See warnings in hammer_unlock_cursor()
3408 		 *	    function.
3409 		 */
3410 		if (error == 0 && ip && ip->ino_data.obj_type ==
3411 				        HAMMER_OBJTYPE_DIRECTORY) {
3412 			hammer_unlock_cursor(&cursor);
3413 			error = hammer_ip_check_directory_empty(trans, ip);
3414 			hammer_lock_cursor(&cursor);
3415 			if (cursor.flags & HAMMER_CURSOR_RETEST) {
3416 				hkprintf("Warning: avoided deadlock "
3417 					"on rmdir '%s'\n",
3418 					ncp->nc_name);
3419 				error = EDEADLK;
3420 			}
3421 		}
3422 
3423 		/*
3424 		 * Delete the directory entry.
3425 		 *
3426 		 * WARNING: hammer_ip_del_direntry() may have to terminate
3427 		 * the cursor to avoid a deadlock.  It is ok to call
3428 		 * hammer_done_cursor() twice.
3429 		 */
3430 		if (error == 0) {
3431 			error = hammer_ip_del_direntry(trans, &cursor,
3432 							dip, ip);
3433 		}
3434 		hammer_done_cursor(&cursor);
3435 		if (error == 0) {
3436 			/*
3437 			 * Tell the namecache that we are now unlinked.
3438 			 */
3439 			cache_unlink(nch);
3440 
3441 			/*
3442 			 * NOTE: ip->vp, if non-NULL, cannot be directly
3443 			 *	 referenced without formally acquiring the
3444 			 *	 vp since the vp might have zero refs on it,
3445 			 *	 or in the middle of a reclaim, etc.
3446 			 *
3447 			 * NOTE: The cache_setunresolved() can rip the vp
3448 			 *	 out from under us since the vp may not have
3449 			 *	 any refs, in which case ip->vp will be NULL
3450 			 *	 from the outset.
3451 			 */
3452 			while (ip && ip->vp) {
3453 				struct vnode *vp;
3454 
3455 				error = hammer_get_vnode(ip, &vp);
3456 				if (error == 0 && vp) {
3457 					vn_unlock(vp);
3458 					hammer_knote(ip->vp, NOTE_DELETE);
3459 #if 0
3460 					/*
3461 					 * Don't do this, it can deadlock
3462 					 * on concurrent rm's of hardlinks.
3463 					 * Shouldn't be needed any more.
3464 					 */
3465 					cache_inval_vp(ip->vp, CINV_DESTROY);
3466 #endif
3467 					vrele(vp);
3468 					break;
3469 				}
3470 				hdkprintf("ip/vp race1 avoided\n");
3471 			}
3472 		}
3473 		if (ip)
3474 			hammer_rel_inode(ip, 0);
3475 	} else {
3476 		hammer_done_cursor(&cursor);
3477 	}
3478 	if (error == EDEADLK)
3479 		goto retry;
3480 
3481 	return (error);
3482 }
3483 
3484 /************************************************************************
3485  *			    FIFO AND SPECFS OPS				*
3486  ************************************************************************
3487  *
3488  */
3489 static int
3490 hammer_vop_fifoclose (struct vop_close_args *ap)
3491 {
3492 	/* XXX update itimes */
3493 	return (VOCALL(&fifo_vnode_vops, &ap->a_head));
3494 }
3495 
3496 static int
3497 hammer_vop_fiforead (struct vop_read_args *ap)
3498 {
3499 	int error;
3500 
3501 	error = VOCALL(&fifo_vnode_vops, &ap->a_head);
3502 	/* XXX update access time */
3503 	return (error);
3504 }
3505 
3506 static int
3507 hammer_vop_fifowrite (struct vop_write_args *ap)
3508 {
3509 	int error;
3510 
3511 	error = VOCALL(&fifo_vnode_vops, &ap->a_head);
3512 	/* XXX update access time */
3513 	return (error);
3514 }
3515 
3516 static
3517 int
3518 hammer_vop_fifokqfilter(struct vop_kqfilter_args *ap)
3519 {
3520 	int error;
3521 
3522 	error = VOCALL(&fifo_vnode_vops, &ap->a_head);
3523 	if (error)
3524 		error = hammer_vop_kqfilter(ap);
3525 	return(error);
3526 }
3527 
3528 /************************************************************************
3529  *			    KQFILTER OPS				*
3530  ************************************************************************
3531  *
3532  */
3533 static void filt_hammerdetach(struct knote *kn);
3534 static int filt_hammerread(struct knote *kn, long hint);
3535 static int filt_hammerwrite(struct knote *kn, long hint);
3536 static int filt_hammervnode(struct knote *kn, long hint);
3537 
3538 static struct filterops hammerread_filtops =
3539 	{ FILTEROP_ISFD | FILTEROP_MPSAFE,
3540 	  NULL, filt_hammerdetach, filt_hammerread };
3541 static struct filterops hammerwrite_filtops =
3542 	{ FILTEROP_ISFD | FILTEROP_MPSAFE,
3543 	  NULL, filt_hammerdetach, filt_hammerwrite };
3544 static struct filterops hammervnode_filtops =
3545 	{ FILTEROP_ISFD | FILTEROP_MPSAFE,
3546 	  NULL, filt_hammerdetach, filt_hammervnode };
3547 
3548 static
3549 int
3550 hammer_vop_kqfilter(struct vop_kqfilter_args *ap)
3551 {
3552 	struct vnode *vp = ap->a_vp;
3553 	struct knote *kn = ap->a_kn;
3554 
3555 	switch (kn->kn_filter) {
3556 	case EVFILT_READ:
3557 		kn->kn_fop = &hammerread_filtops;
3558 		break;
3559 	case EVFILT_WRITE:
3560 		kn->kn_fop = &hammerwrite_filtops;
3561 		break;
3562 	case EVFILT_VNODE:
3563 		kn->kn_fop = &hammervnode_filtops;
3564 		break;
3565 	default:
3566 		return (EOPNOTSUPP);
3567 	}
3568 
3569 	kn->kn_hook = (caddr_t)vp;
3570 
3571 	knote_insert(&vp->v_pollinfo.vpi_kqinfo.ki_note, kn);
3572 
3573 	return(0);
3574 }
3575 
3576 static void
3577 filt_hammerdetach(struct knote *kn)
3578 {
3579 	struct vnode *vp = (void *)kn->kn_hook;
3580 
3581 	knote_remove(&vp->v_pollinfo.vpi_kqinfo.ki_note, kn);
3582 }
3583 
3584 static int
3585 filt_hammerread(struct knote *kn, long hint)
3586 {
3587 	struct vnode *vp = (void *)kn->kn_hook;
3588 	hammer_inode_t ip = VTOI(vp);
3589 	hammer_mount_t hmp = ip->hmp;
3590 	off_t off;
3591 
3592 	if (hint == NOTE_REVOKE) {
3593 		kn->kn_flags |= (EV_EOF | EV_NODATA | EV_ONESHOT);
3594 		return(1);
3595 	}
3596 	lwkt_gettoken(&hmp->fs_token);	/* XXX use per-ip-token */
3597 	off = ip->ino_data.size - kn->kn_fp->f_offset;
3598 	kn->kn_data = (off < INTPTR_MAX) ? off : INTPTR_MAX;
3599 	lwkt_reltoken(&hmp->fs_token);
3600 	if (kn->kn_sfflags & NOTE_OLDAPI)
3601 		return(1);
3602 	return (kn->kn_data != 0);
3603 }
3604 
3605 static int
3606 filt_hammerwrite(struct knote *kn, long hint)
3607 {
3608 	if (hint == NOTE_REVOKE)
3609 		kn->kn_flags |= (EV_EOF | EV_NODATA | EV_ONESHOT);
3610 	kn->kn_data = 0;
3611 	return (1);
3612 }
3613 
3614 static int
3615 filt_hammervnode(struct knote *kn, long hint)
3616 {
3617 	if (kn->kn_sfflags & hint)
3618 		kn->kn_fflags |= hint;
3619 	if (hint == NOTE_REVOKE) {
3620 		kn->kn_flags |= (EV_EOF | EV_NODATA);
3621 		return (1);
3622 	}
3623 	return (kn->kn_fflags != 0);
3624 }
3625 
3626