xref: /dflybsd-src/sys/vfs/hammer/hammer_vfsops.c (revision a9656fbcd49c376aba5e04370d8b0f1fa96e063c)
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  * $DragonFly: src/sys/vfs/hammer/hammer_vfsops.c,v 1.74 2008/11/13 02:18:43 dillon Exp $
35  */
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/kernel.h>
40 #include <sys/vnode.h>
41 #include <sys/mount.h>
42 #include <sys/malloc.h>
43 #include <sys/nlookup.h>
44 #include <sys/fcntl.h>
45 #include <sys/sysctl.h>
46 #include <sys/buf.h>
47 #include <sys/buf2.h>
48 #include "hammer.h"
49 
50 /*
51  * NOTE!  Global statistics may not be MPSAFE so HAMMER never uses them
52  *	  in conditionals.
53  */
54 int hammer_supported_version = HAMMER_VOL_VERSION_DEFAULT;
55 int hammer_debug_io;
56 int hammer_debug_general;
57 int hammer_debug_debug = 1;		/* medium-error panics */
58 int hammer_debug_inode;
59 int hammer_debug_locks;
60 int hammer_debug_btree;
61 int hammer_debug_tid;
62 int hammer_debug_recover;		/* -1 will disable, +1 will force */
63 int hammer_debug_recover_faults;
64 int hammer_debug_critical;		/* non-zero enter debugger on error */
65 int hammer_cluster_enable = 1;		/* enable read clustering by default */
66 int hammer_count_fsyncs;
67 int hammer_count_inodes;
68 int hammer_count_iqueued;
69 int hammer_count_reclaiming;
70 int hammer_count_records;
71 int hammer_count_record_datas;
72 int hammer_count_volumes;
73 int hammer_count_buffers;
74 int hammer_count_nodes;
75 int64_t hammer_count_extra_space_used;
76 int64_t hammer_stats_btree_lookups;
77 int64_t hammer_stats_btree_searches;
78 int64_t hammer_stats_btree_inserts;
79 int64_t hammer_stats_btree_deletes;
80 int64_t hammer_stats_btree_elements;
81 int64_t hammer_stats_btree_splits;
82 int64_t hammer_stats_btree_iterations;
83 int64_t hammer_stats_btree_root_iterations;
84 int64_t hammer_stats_record_iterations;
85 
86 int64_t hammer_stats_file_read;
87 int64_t hammer_stats_file_write;
88 int64_t hammer_stats_file_iopsr;
89 int64_t hammer_stats_file_iopsw;
90 int64_t hammer_stats_disk_read;
91 int64_t hammer_stats_disk_write;
92 int64_t hammer_stats_inode_flushes;
93 int64_t hammer_stats_commits;
94 int64_t hammer_stats_undo;
95 int64_t hammer_stats_redo;
96 
97 int hammer_count_dirtybufspace;		/* global */
98 int hammer_count_refedbufs;		/* global */
99 int hammer_count_reservations;
100 int hammer_count_io_running_read;
101 int hammer_count_io_running_write;
102 int hammer_count_io_locked;
103 int hammer_limit_dirtybufspace;		/* per-mount */
104 int hammer_limit_running_io;		/* per-mount */
105 int hammer_limit_recs;			/* as a whole XXX */
106 int hammer_limit_inode_recs = 1024;	/* per inode */
107 int hammer_limit_reclaim = HAMMER_RECLAIM_WAIT;
108 int hammer_limit_redo = 4096 * 1024;	/* per inode */
109 int hammer_autoflush = 2000;		/* auto flush */
110 int hammer_bio_count;
111 int hammer_verify_zone;
112 int hammer_verify_data = 1;
113 int hammer_write_mode;
114 int hammer_yield_check = 16;
115 int hammer_fsync_mode = 3;
116 int64_t hammer_contention_count;
117 int64_t hammer_zone_limit;
118 
119 SYSCTL_NODE(_vfs, OID_AUTO, hammer, CTLFLAG_RW, 0, "HAMMER filesystem");
120 SYSCTL_INT(_vfs_hammer, OID_AUTO, supported_version, CTLFLAG_RD,
121 	   &hammer_supported_version, 0, "");
122 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_general, CTLFLAG_RW,
123 	   &hammer_debug_general, 0, "");
124 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_io, CTLFLAG_RW,
125 	   &hammer_debug_io, 0, "");
126 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_debug, CTLFLAG_RW,
127 	   &hammer_debug_debug, 0, "");
128 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_inode, CTLFLAG_RW,
129 	   &hammer_debug_inode, 0, "");
130 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_locks, CTLFLAG_RW,
131 	   &hammer_debug_locks, 0, "");
132 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_btree, CTLFLAG_RW,
133 	   &hammer_debug_btree, 0, "");
134 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_tid, CTLFLAG_RW,
135 	   &hammer_debug_tid, 0, "");
136 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_recover, CTLFLAG_RW,
137 	   &hammer_debug_recover, 0, "");
138 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_recover_faults, CTLFLAG_RW,
139 	   &hammer_debug_recover_faults, 0, "");
140 SYSCTL_INT(_vfs_hammer, OID_AUTO, debug_critical, CTLFLAG_RW,
141 	   &hammer_debug_critical, 0, "");
142 SYSCTL_INT(_vfs_hammer, OID_AUTO, cluster_enable, CTLFLAG_RW,
143 	   &hammer_cluster_enable, 0, "");
144 
145 SYSCTL_INT(_vfs_hammer, OID_AUTO, limit_dirtybufspace, CTLFLAG_RW,
146 	   &hammer_limit_dirtybufspace, 0, "");
147 SYSCTL_INT(_vfs_hammer, OID_AUTO, limit_running_io, CTLFLAG_RW,
148 	   &hammer_limit_running_io, 0, "");
149 SYSCTL_INT(_vfs_hammer, OID_AUTO, limit_recs, CTLFLAG_RW,
150 	   &hammer_limit_recs, 0, "");
151 SYSCTL_INT(_vfs_hammer, OID_AUTO, limit_inode_recs, CTLFLAG_RW,
152 	   &hammer_limit_inode_recs, 0, "");
153 SYSCTL_INT(_vfs_hammer, OID_AUTO, limit_reclaim, CTLFLAG_RW,
154 	   &hammer_limit_reclaim, 0, "");
155 SYSCTL_INT(_vfs_hammer, OID_AUTO, limit_redo, CTLFLAG_RW,
156 	   &hammer_limit_redo, 0, "");
157 
158 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_fsyncs, CTLFLAG_RD,
159 	   &hammer_count_fsyncs, 0, "");
160 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_inodes, CTLFLAG_RD,
161 	   &hammer_count_inodes, 0, "");
162 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_iqueued, CTLFLAG_RD,
163 	   &hammer_count_iqueued, 0, "");
164 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_reclaiming, CTLFLAG_RD,
165 	   &hammer_count_reclaiming, 0, "");
166 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_records, CTLFLAG_RD,
167 	   &hammer_count_records, 0, "");
168 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_record_datas, CTLFLAG_RD,
169 	   &hammer_count_record_datas, 0, "");
170 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_volumes, CTLFLAG_RD,
171 	   &hammer_count_volumes, 0, "");
172 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_buffers, CTLFLAG_RD,
173 	   &hammer_count_buffers, 0, "");
174 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_nodes, CTLFLAG_RD,
175 	   &hammer_count_nodes, 0, "");
176 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, count_extra_space_used, CTLFLAG_RD,
177 	   &hammer_count_extra_space_used, 0, "");
178 
179 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_searches, CTLFLAG_RD,
180 	   &hammer_stats_btree_searches, 0, "");
181 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_lookups, CTLFLAG_RD,
182 	   &hammer_stats_btree_lookups, 0, "");
183 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_inserts, CTLFLAG_RD,
184 	   &hammer_stats_btree_inserts, 0, "");
185 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_deletes, CTLFLAG_RD,
186 	   &hammer_stats_btree_deletes, 0, "");
187 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_elements, CTLFLAG_RD,
188 	   &hammer_stats_btree_elements, 0, "");
189 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_splits, CTLFLAG_RD,
190 	   &hammer_stats_btree_splits, 0, "");
191 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_iterations, CTLFLAG_RD,
192 	   &hammer_stats_btree_iterations, 0, "");
193 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_btree_root_iterations, CTLFLAG_RD,
194 	   &hammer_stats_btree_root_iterations, 0, "");
195 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_record_iterations, CTLFLAG_RD,
196 	   &hammer_stats_record_iterations, 0, "");
197 
198 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_file_read, CTLFLAG_RD,
199 	   &hammer_stats_file_read, 0, "");
200 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_file_write, CTLFLAG_RD,
201 	   &hammer_stats_file_write, 0, "");
202 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_file_iopsr, CTLFLAG_RD,
203 	   &hammer_stats_file_iopsr, 0, "");
204 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_file_iopsw, CTLFLAG_RD,
205 	   &hammer_stats_file_iopsw, 0, "");
206 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_disk_read, CTLFLAG_RD,
207 	   &hammer_stats_disk_read, 0, "");
208 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_disk_write, CTLFLAG_RD,
209 	   &hammer_stats_disk_write, 0, "");
210 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_inode_flushes, CTLFLAG_RD,
211 	   &hammer_stats_inode_flushes, 0, "");
212 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_commits, CTLFLAG_RD,
213 	   &hammer_stats_commits, 0, "");
214 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_undo, CTLFLAG_RD,
215 	   &hammer_stats_undo, 0, "");
216 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, stats_redo, CTLFLAG_RD,
217 	   &hammer_stats_redo, 0, "");
218 
219 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_dirtybufspace, CTLFLAG_RD,
220 	   &hammer_count_dirtybufspace, 0, "");
221 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_refedbufs, CTLFLAG_RD,
222 	   &hammer_count_refedbufs, 0, "");
223 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_reservations, CTLFLAG_RD,
224 	   &hammer_count_reservations, 0, "");
225 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_io_running_read, CTLFLAG_RD,
226 	   &hammer_count_io_running_read, 0, "");
227 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_io_locked, CTLFLAG_RD,
228 	   &hammer_count_io_locked, 0, "");
229 SYSCTL_INT(_vfs_hammer, OID_AUTO, count_io_running_write, CTLFLAG_RD,
230 	   &hammer_count_io_running_write, 0, "");
231 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, zone_limit, CTLFLAG_RW,
232 	   &hammer_zone_limit, 0, "");
233 SYSCTL_QUAD(_vfs_hammer, OID_AUTO, contention_count, CTLFLAG_RW,
234 	   &hammer_contention_count, 0, "");
235 SYSCTL_INT(_vfs_hammer, OID_AUTO, autoflush, CTLFLAG_RW,
236 	   &hammer_autoflush, 0, "");
237 SYSCTL_INT(_vfs_hammer, OID_AUTO, verify_zone, CTLFLAG_RW,
238 	   &hammer_verify_zone, 0, "");
239 SYSCTL_INT(_vfs_hammer, OID_AUTO, verify_data, CTLFLAG_RW,
240 	   &hammer_verify_data, 0, "");
241 SYSCTL_INT(_vfs_hammer, OID_AUTO, write_mode, CTLFLAG_RW,
242 	   &hammer_write_mode, 0, "");
243 SYSCTL_INT(_vfs_hammer, OID_AUTO, yield_check, CTLFLAG_RW,
244 	   &hammer_yield_check, 0, "");
245 SYSCTL_INT(_vfs_hammer, OID_AUTO, fsync_mode, CTLFLAG_RW,
246 	   &hammer_fsync_mode, 0, "");
247 
248 KTR_INFO_MASTER(hammer);
249 
250 /*
251  * VFS ABI
252  */
253 static void	hammer_free_hmp(struct mount *mp);
254 
255 static int	hammer_vfs_mount(struct mount *mp, char *path, caddr_t data,
256 				struct ucred *cred);
257 static int	hammer_vfs_unmount(struct mount *mp, int mntflags);
258 static int	hammer_vfs_root(struct mount *mp, struct vnode **vpp);
259 static int	hammer_vfs_statfs(struct mount *mp, struct statfs *sbp,
260 				struct ucred *cred);
261 static int	hammer_vfs_statvfs(struct mount *mp, struct statvfs *sbp,
262 				struct ucred *cred);
263 static int	hammer_vfs_sync(struct mount *mp, int waitfor);
264 static int	hammer_vfs_vget(struct mount *mp, struct vnode *dvp,
265 				ino_t ino, struct vnode **vpp);
266 static int	hammer_vfs_init(struct vfsconf *conf);
267 static int	hammer_vfs_fhtovp(struct mount *mp, struct vnode *rootvp,
268 				struct fid *fhp, struct vnode **vpp);
269 static int	hammer_vfs_vptofh(struct vnode *vp, struct fid *fhp);
270 static int	hammer_vfs_checkexp(struct mount *mp, struct sockaddr *nam,
271 				int *exflagsp, struct ucred **credanonp);
272 
273 
274 static struct vfsops hammer_vfsops = {
275 	.vfs_mount	= hammer_vfs_mount,
276 	.vfs_unmount	= hammer_vfs_unmount,
277 	.vfs_root 	= hammer_vfs_root,
278 	.vfs_statfs	= hammer_vfs_statfs,
279 	.vfs_statvfs	= hammer_vfs_statvfs,
280 	.vfs_sync	= hammer_vfs_sync,
281 	.vfs_vget	= hammer_vfs_vget,
282 	.vfs_init	= hammer_vfs_init,
283 	.vfs_vptofh	= hammer_vfs_vptofh,
284 	.vfs_fhtovp	= hammer_vfs_fhtovp,
285 	.vfs_checkexp	= hammer_vfs_checkexp
286 };
287 
288 MALLOC_DEFINE(M_HAMMER, "HAMMER-mount", "");
289 
290 VFS_SET(hammer_vfsops, hammer, 0);
291 MODULE_VERSION(hammer, 1);
292 
293 static int
294 hammer_vfs_init(struct vfsconf *conf)
295 {
296 	int n;
297 
298 	if (hammer_limit_recs == 0) {
299 		hammer_limit_recs = nbuf * 25;
300 		n = kmalloc_limit(M_HAMMER) / 512;
301 		if (hammer_limit_recs > n)
302 			hammer_limit_recs = n;
303 	}
304 	if (hammer_limit_dirtybufspace == 0) {
305 		hammer_limit_dirtybufspace = hidirtybufspace / 2;
306 		if (hammer_limit_dirtybufspace < 100)
307 			hammer_limit_dirtybufspace = 100;
308 	}
309 
310 	/*
311 	 * Set reasonable limits to maintain an I/O pipeline.  This is
312 	 * used by the flush code which explicitly initiates I/O, and
313 	 * is per-mount.
314 	 *
315 	 * The system-driven buffer cache uses vfs.lorunningspace and
316 	 * vfs.hirunningspace globally.
317 	 */
318 	if (hammer_limit_running_io == 0)
319 		hammer_limit_running_io = hammer_limit_dirtybufspace;
320 	if (hammer_limit_running_io > 10 * 1024 * 1024)
321 		hammer_limit_running_io = 10 * 1024 * 1024;
322 	return(0);
323 }
324 
325 static int
326 hammer_vfs_mount(struct mount *mp, char *mntpt, caddr_t data,
327 		 struct ucred *cred)
328 {
329 	struct hammer_mount_info info;
330 	hammer_mount_t hmp;
331 	hammer_volume_t rootvol;
332 	struct vnode *rootvp;
333 	struct vnode *devvp = NULL;
334 	const char *upath;	/* volume name in userspace */
335 	char *path;		/* volume name in system space */
336 	int error;
337 	int i;
338 	int master_id;
339 	char *next_volume_ptr = NULL;
340 
341 	/*
342 	 * Accept hammer_mount_info.  mntpt is NULL for root mounts at boot.
343 	 */
344 	if (mntpt == NULL) {
345 		bzero(&info, sizeof(info));
346 		info.asof = 0;
347 		info.hflags = 0;
348 		info.nvolumes = 1;
349 
350 		next_volume_ptr = mp->mnt_stat.f_mntfromname;
351 
352 		/* Count number of volumes separated by ':' */
353 		for (char *p = next_volume_ptr; *p != '\0'; ++p) {
354 			if (*p == ':') {
355 				++info.nvolumes;
356 			}
357 		}
358 
359 		mp->mnt_flag &= ~MNT_RDONLY; /* mount R/W */
360 	} else {
361 		if ((error = copyin(data, &info, sizeof(info))) != 0)
362 			return (error);
363 	}
364 
365 	/*
366 	 * updating or new mount
367 	 */
368 	if (mp->mnt_flag & MNT_UPDATE) {
369 		hmp = (void *)mp->mnt_data;
370 		KKASSERT(hmp != NULL);
371 	} else {
372 		if (info.nvolumes <= 0 || info.nvolumes >= 32768)
373 			return (EINVAL);
374 		hmp = NULL;
375 	}
376 
377 	/*
378 	 * master-id validation.  The master id may not be changed by a
379 	 * mount update.
380 	 */
381 	if (info.hflags & HMNT_MASTERID) {
382 		if (hmp && hmp->master_id != info.master_id) {
383 			kprintf("hammer: cannot change master id "
384 				"with mount update\n");
385 			return(EINVAL);
386 		}
387 		master_id = info.master_id;
388 		if (master_id < -1 || master_id >= HAMMER_MAX_MASTERS)
389 			return (EINVAL);
390 	} else {
391 		if (hmp)
392 			master_id = hmp->master_id;
393 		else
394 			master_id = 0;
395 	}
396 
397 	/*
398 	 * Interal mount data structure
399 	 */
400 	if (hmp == NULL) {
401 		hmp = kmalloc(sizeof(*hmp), M_HAMMER, M_WAITOK | M_ZERO);
402 		mp->mnt_data = (qaddr_t)hmp;
403 		hmp->mp = mp;
404 		/*TAILQ_INIT(&hmp->recycle_list);*/
405 
406 		/*
407 		 * Make sure kmalloc type limits are set appropriately.
408 		 *
409 		 * Our inode kmalloc group is sized based on maxvnodes
410 		 * (controlled by the system, not us).
411 		 */
412 		kmalloc_create(&hmp->m_misc, "HAMMER-others");
413 		kmalloc_create(&hmp->m_inodes, "HAMMER-inodes");
414 
415 		kmalloc_raise_limit(hmp->m_inodes, 0);	/* unlimited */
416 
417 		hmp->root_btree_beg.localization = 0x00000000U;
418 		hmp->root_btree_beg.obj_id = -0x8000000000000000LL;
419 		hmp->root_btree_beg.key = -0x8000000000000000LL;
420 		hmp->root_btree_beg.create_tid = 1;
421 		hmp->root_btree_beg.delete_tid = 1;
422 		hmp->root_btree_beg.rec_type = 0;
423 		hmp->root_btree_beg.obj_type = 0;
424 
425 		hmp->root_btree_end.localization = 0xFFFFFFFFU;
426 		hmp->root_btree_end.obj_id = 0x7FFFFFFFFFFFFFFFLL;
427 		hmp->root_btree_end.key = 0x7FFFFFFFFFFFFFFFLL;
428 		hmp->root_btree_end.create_tid = 0xFFFFFFFFFFFFFFFFULL;
429 		hmp->root_btree_end.delete_tid = 0;   /* special case */
430 		hmp->root_btree_end.rec_type = 0xFFFFU;
431 		hmp->root_btree_end.obj_type = 0;
432 
433 		hmp->krate.freq = 1;	/* maximum reporting rate (hz) */
434 		hmp->krate.count = -16;	/* initial burst */
435 
436 		hmp->sync_lock.refs = 1;
437 		hmp->free_lock.refs = 1;
438 		hmp->undo_lock.refs = 1;
439 		hmp->blkmap_lock.refs = 1;
440 		hmp->snapshot_lock.refs = 1;
441 		hmp->volume_lock.refs = 1;
442 
443 		TAILQ_INIT(&hmp->delay_list);
444 		TAILQ_INIT(&hmp->flush_group_list);
445 		TAILQ_INIT(&hmp->objid_cache_list);
446 		TAILQ_INIT(&hmp->undo_lru_list);
447 		TAILQ_INIT(&hmp->reclaim_list);
448 	}
449 	hmp->hflags &= ~HMNT_USERFLAGS;
450 	hmp->hflags |= info.hflags & HMNT_USERFLAGS;
451 
452 	hmp->master_id = master_id;
453 
454 	if (info.asof) {
455 		mp->mnt_flag |= MNT_RDONLY;
456 		hmp->asof = info.asof;
457 	} else {
458 		hmp->asof = HAMMER_MAX_TID;
459 	}
460 
461 	hmp->volume_to_remove = -1;
462 
463 	/*
464 	 * Re-open read-write if originally read-only, or vise-versa.
465 	 *
466 	 * When going from read-only to read-write execute the stage2
467 	 * recovery if it has not already been run.
468 	 */
469 	if (mp->mnt_flag & MNT_UPDATE) {
470 		error = 0;
471 		if (hmp->ronly && (mp->mnt_kern_flag & MNTK_WANTRDWR)) {
472 			kprintf("HAMMER read-only -> read-write\n");
473 			hmp->ronly = 0;
474 			RB_SCAN(hammer_vol_rb_tree, &hmp->rb_vols_root, NULL,
475 				hammer_adjust_volume_mode, NULL);
476 			rootvol = hammer_get_root_volume(hmp, &error);
477 			if (rootvol) {
478 				hammer_recover_flush_buffers(hmp, rootvol, 1);
479 				error = hammer_recover_stage2(hmp, rootvol);
480 				bcopy(rootvol->ondisk->vol0_blockmap,
481 				      hmp->blockmap,
482 				      sizeof(hmp->blockmap));
483 				hammer_rel_volume(rootvol, 0);
484 			}
485 			RB_SCAN(hammer_ino_rb_tree, &hmp->rb_inos_root, NULL,
486 				hammer_reload_inode, NULL);
487 			/* kernel clears MNT_RDONLY */
488 		} else if (hmp->ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) {
489 			kprintf("HAMMER read-write -> read-only\n");
490 			hmp->ronly = 1;	/* messy */
491 			RB_SCAN(hammer_ino_rb_tree, &hmp->rb_inos_root, NULL,
492 				hammer_reload_inode, NULL);
493 			hmp->ronly = 0;
494 			hammer_flusher_sync(hmp);
495 			hammer_flusher_sync(hmp);
496 			hammer_flusher_sync(hmp);
497 			hmp->ronly = 1;
498 			RB_SCAN(hammer_vol_rb_tree, &hmp->rb_vols_root, NULL,
499 				hammer_adjust_volume_mode, NULL);
500 		}
501 		return(error);
502 	}
503 
504 	RB_INIT(&hmp->rb_vols_root);
505 	RB_INIT(&hmp->rb_inos_root);
506 	RB_INIT(&hmp->rb_redo_root);
507 	RB_INIT(&hmp->rb_nods_root);
508 	RB_INIT(&hmp->rb_undo_root);
509 	RB_INIT(&hmp->rb_resv_root);
510 	RB_INIT(&hmp->rb_bufs_root);
511 	RB_INIT(&hmp->rb_pfsm_root);
512 
513 	hmp->ronly = ((mp->mnt_flag & MNT_RDONLY) != 0);
514 
515 	TAILQ_INIT(&hmp->volu_list);
516 	TAILQ_INIT(&hmp->undo_list);
517 	TAILQ_INIT(&hmp->data_list);
518 	TAILQ_INIT(&hmp->meta_list);
519 	TAILQ_INIT(&hmp->lose_list);
520 	TAILQ_INIT(&hmp->iorun_list);
521 
522 	/*
523 	 * Load volumes
524 	 */
525 	path = objcache_get(namei_oc, M_WAITOK);
526 	hmp->nvolumes = -1;
527 	for (i = 0; i < info.nvolumes; ++i) {
528 		if (mntpt == NULL) {
529 			/*
530 			 * Root mount.
531 			 */
532 			KKASSERT(next_volume_ptr != NULL);
533 			strcpy(path, "");
534 			if (*next_volume_ptr != '/') {
535 				/* relative path */
536 				strcpy(path, "/dev/");
537 			}
538 			int k;
539 			for (k = strlen(path); k < MAXPATHLEN-1; ++k) {
540 				if (*next_volume_ptr == '\0') {
541 					break;
542 				} else if (*next_volume_ptr == ':') {
543 					++next_volume_ptr;
544 					break;
545 				} else {
546 					path[k] = *next_volume_ptr;
547 					++next_volume_ptr;
548 				}
549 			}
550 			path[k] = '\0';
551 
552 			error = 0;
553 			cdev_t dev = kgetdiskbyname(path);
554 			error = bdevvp(dev, &devvp);
555 			if (error) {
556 				kprintf("hammer_mountroot: can't find devvp\n");
557 			}
558 		} else {
559 			error = copyin(&info.volumes[i], &upath,
560 				       sizeof(char *));
561 			if (error == 0)
562 				error = copyinstr(upath, path,
563 						  MAXPATHLEN, NULL);
564 		}
565 		if (error == 0)
566 			error = hammer_install_volume(hmp, path, devvp);
567 		if (error)
568 			break;
569 	}
570 	objcache_put(namei_oc, path);
571 
572 	/*
573 	 * Make sure we found a root volume
574 	 */
575 	if (error == 0 && hmp->rootvol == NULL) {
576 		kprintf("hammer_mount: No root volume found!\n");
577 		error = EINVAL;
578 	}
579 
580 	/*
581 	 * Check that all required volumes are available
582 	 */
583 	if (error == 0 && hammer_mountcheck_volumes(hmp)) {
584 		kprintf("hammer_mount: Missing volumes, cannot mount!\n");
585 		error = EINVAL;
586 	}
587 
588 	if (error) {
589 		hammer_free_hmp(mp);
590 		return (error);
591 	}
592 
593 	/*
594 	 * No errors, setup enough of the mount point so we can lookup the
595 	 * root vnode.
596 	 */
597 	mp->mnt_iosize_max = MAXPHYS;
598 	mp->mnt_kern_flag |= MNTK_FSMID;
599 
600 	/*
601 	 * MPSAFE code.  Note that VOPs and VFSops which are not MPSAFE
602 	 * will acquire a per-mount token prior to entry and release it
603 	 * on return, so even if we do not specify it we no longer get
604 	 * the BGL regardlless of how we are flagged.
605 	 */
606 	mp->mnt_kern_flag |= MNTK_RD_MPSAFE | MNTK_GA_MPSAFE |
607 			     MNTK_IN_MPSAFE;
608 
609 	/*
610 	 * note: f_iosize is used by vnode_pager_haspage() when constructing
611 	 * its VOP_BMAP call.
612 	 */
613 	mp->mnt_stat.f_iosize = HAMMER_BUFSIZE;
614 	mp->mnt_stat.f_bsize = HAMMER_BUFSIZE;
615 
616 	mp->mnt_vstat.f_frsize = HAMMER_BUFSIZE;
617 	mp->mnt_vstat.f_bsize = HAMMER_BUFSIZE;
618 
619 	mp->mnt_maxsymlinklen = 255;
620 	mp->mnt_flag |= MNT_LOCAL;
621 
622 	vfs_add_vnodeops(mp, &hammer_vnode_vops, &mp->mnt_vn_norm_ops);
623 	vfs_add_vnodeops(mp, &hammer_spec_vops, &mp->mnt_vn_spec_ops);
624 	vfs_add_vnodeops(mp, &hammer_fifo_vops, &mp->mnt_vn_fifo_ops);
625 
626 	/*
627 	 * The root volume's ondisk pointer is only valid if we hold a
628 	 * reference to it.
629 	 */
630 	rootvol = hammer_get_root_volume(hmp, &error);
631 	if (error)
632 		goto failed;
633 
634 	/*
635 	 * Perform any necessary UNDO operations.  The recovery code does
636 	 * call hammer_undo_lookup() so we have to pre-cache the blockmap,
637 	 * and then re-copy it again after recovery is complete.
638 	 *
639 	 * If this is a read-only mount the UNDO information is retained
640 	 * in memory in the form of dirty buffer cache buffers, and not
641 	 * written back to the media.
642 	 */
643 	bcopy(rootvol->ondisk->vol0_blockmap, hmp->blockmap,
644 	      sizeof(hmp->blockmap));
645 
646 	/*
647 	 * Check filesystem version
648 	 */
649 	hmp->version = rootvol->ondisk->vol_version;
650 	if (hmp->version < HAMMER_VOL_VERSION_MIN ||
651 	    hmp->version > HAMMER_VOL_VERSION_MAX) {
652 		kprintf("HAMMER: mount unsupported fs version %d\n",
653 			hmp->version);
654 		error = ERANGE;
655 		goto done;
656 	}
657 
658 	/*
659 	 * The undo_rec_limit limits the size of flush groups to avoid
660 	 * blowing out the UNDO FIFO.  This calculation is typically in
661 	 * the tens of thousands and is designed primarily when small
662 	 * HAMMER filesystems are created.
663 	 */
664 	hmp->undo_rec_limit = hammer_undo_max(hmp) / 8192 + 100;
665 	if (hammer_debug_general & 0x0001)
666 		kprintf("HAMMER: undo_rec_limit %d\n", hmp->undo_rec_limit);
667 
668 	/*
669 	 * NOTE: Recover stage1 not only handles meta-data recovery, it
670 	 * 	 also sets hmp->undo_seqno for HAMMER VERSION 4+ filesystems.
671 	 */
672 	error = hammer_recover_stage1(hmp, rootvol);
673 	if (error) {
674 		kprintf("Failed to recover HAMMER filesystem on mount\n");
675 		goto done;
676 	}
677 
678 	/*
679 	 * Finish setup now that we have a good root volume.
680 	 *
681 	 * The top 16 bits of fsid.val[1] is a pfs id.
682 	 */
683 	ksnprintf(mp->mnt_stat.f_mntfromname,
684 		  sizeof(mp->mnt_stat.f_mntfromname), "%s",
685 		  rootvol->ondisk->vol_name);
686 	mp->mnt_stat.f_fsid.val[0] =
687 		crc32((char *)&rootvol->ondisk->vol_fsid + 0, 8);
688 	mp->mnt_stat.f_fsid.val[1] =
689 		crc32((char *)&rootvol->ondisk->vol_fsid + 8, 8);
690 	mp->mnt_stat.f_fsid.val[1] &= 0x0000FFFF;
691 
692 	mp->mnt_vstat.f_fsid_uuid = rootvol->ondisk->vol_fsid;
693 	mp->mnt_vstat.f_fsid = crc32(&mp->mnt_vstat.f_fsid_uuid,
694 				     sizeof(mp->mnt_vstat.f_fsid_uuid));
695 
696 	/*
697 	 * Certain often-modified fields in the root volume are cached in
698 	 * the hammer_mount structure so we do not have to generate lots
699 	 * of little UNDO structures for them.
700 	 *
701 	 * Recopy after recovery.  This also has the side effect of
702 	 * setting our cached undo FIFO's first_offset, which serves to
703 	 * placemark the FIFO start for the NEXT flush cycle while the
704 	 * on-disk first_offset represents the LAST flush cycle.
705 	 */
706 	hmp->next_tid = rootvol->ondisk->vol0_next_tid;
707 	hmp->flush_tid1 = hmp->next_tid;
708 	hmp->flush_tid2 = hmp->next_tid;
709 	bcopy(rootvol->ondisk->vol0_blockmap, hmp->blockmap,
710 	      sizeof(hmp->blockmap));
711 	hmp->copy_stat_freebigblocks = rootvol->ondisk->vol0_stat_freebigblocks;
712 
713 	hammer_flusher_create(hmp);
714 
715 	/*
716 	 * Locate the root directory using the root cluster's B-Tree as a
717 	 * starting point.  The root directory uses an obj_id of 1.
718 	 *
719 	 * FUTURE: Leave the root directory cached referenced but unlocked
720 	 * in hmp->rootvp (need to flush it on unmount).
721 	 */
722 	error = hammer_vfs_vget(mp, NULL, 1, &rootvp);
723 	if (error)
724 		goto done;
725 	vput(rootvp);
726 	/*vn_unlock(hmp->rootvp);*/
727 	if (hmp->ronly == 0)
728 		error = hammer_recover_stage2(hmp, rootvol);
729 
730 done:
731 	hammer_rel_volume(rootvol, 0);
732 failed:
733 	/*
734 	 * Cleanup and return.
735 	 */
736 	if (error)
737 		hammer_free_hmp(mp);
738 	return (error);
739 }
740 
741 static int
742 hammer_vfs_unmount(struct mount *mp, int mntflags)
743 {
744 #if 0
745 	struct hammer_mount *hmp = (void *)mp->mnt_data;
746 #endif
747 	int flags;
748 	int error;
749 
750 	/*
751 	 * Clean out the vnodes
752 	 */
753 	flags = 0;
754 	if (mntflags & MNT_FORCE)
755 		flags |= FORCECLOSE;
756 	if ((error = vflush(mp, 0, flags)) != 0)
757 		return (error);
758 
759 	/*
760 	 * Clean up the internal mount structure and related entities.  This
761 	 * may issue I/O.
762 	 */
763 	hammer_free_hmp(mp);
764 	return(0);
765 }
766 
767 /*
768  * Clean up the internal mount structure and disassociate it from the mount.
769  * This may issue I/O.
770  */
771 static void
772 hammer_free_hmp(struct mount *mp)
773 {
774 	struct hammer_mount *hmp = (void *)mp->mnt_data;
775 	hammer_flush_group_t flg;
776 	int count;
777 	int dummy;
778 
779 	/*
780 	 * Flush anything dirty.  This won't even run if the
781 	 * filesystem errored-out.
782 	 */
783 	count = 0;
784 	while (hammer_flusher_haswork(hmp)) {
785 		hammer_flusher_sync(hmp);
786 		++count;
787 		if (count >= 5) {
788 			if (count == 5)
789 				kprintf("HAMMER: umount flushing.");
790 			else
791 				kprintf(".");
792 			tsleep(&dummy, 0, "hmrufl", hz);
793 		}
794 		if (count == 30) {
795 			kprintf("giving up\n");
796 			break;
797 		}
798 	}
799 	if (count >= 5 && count < 30)
800 		kprintf("\n");
801 
802 	/*
803 	 * If the mount had a critical error we have to destroy any
804 	 * remaining inodes before we can finish cleaning up the flusher.
805 	 */
806 	if (hmp->flags & HAMMER_MOUNT_CRITICAL_ERROR) {
807 		RB_SCAN(hammer_ino_rb_tree, &hmp->rb_inos_root, NULL,
808 			hammer_destroy_inode_callback, NULL);
809 	}
810 
811 	/*
812 	 * There shouldn't be any inodes left now and any left over
813 	 * flush groups should now be empty.
814 	 */
815 	KKASSERT(RB_EMPTY(&hmp->rb_inos_root));
816 	while ((flg = TAILQ_FIRST(&hmp->flush_group_list)) != NULL) {
817 		TAILQ_REMOVE(&hmp->flush_group_list, flg, flush_entry);
818 		KKASSERT(RB_EMPTY(&flg->flush_tree));
819 		if (flg->refs) {
820 			kprintf("HAMMER: Warning, flush_group %p was "
821 				"not empty on umount!\n", flg);
822 		}
823 		kfree(flg, hmp->m_misc);
824 	}
825 
826 	/*
827 	 * We can finally destroy the flusher
828 	 */
829 	hammer_flusher_destroy(hmp);
830 
831 	/*
832 	 * We may have held recovered buffers due to a read-only mount.
833 	 * These must be discarded.
834 	 */
835 	if (hmp->ronly)
836 		hammer_recover_flush_buffers(hmp, NULL, -1);
837 
838 	/*
839 	 * Unload buffers and then volumes
840 	 */
841         RB_SCAN(hammer_buf_rb_tree, &hmp->rb_bufs_root, NULL,
842 		hammer_unload_buffer, NULL);
843 	RB_SCAN(hammer_vol_rb_tree, &hmp->rb_vols_root, NULL,
844 		hammer_unload_volume, NULL);
845 
846 	mp->mnt_data = NULL;
847 	mp->mnt_flag &= ~MNT_LOCAL;
848 	hmp->mp = NULL;
849 	hammer_destroy_objid_cache(hmp);
850 	kmalloc_destroy(&hmp->m_misc);
851 	kmalloc_destroy(&hmp->m_inodes);
852 	kfree(hmp, M_HAMMER);
853 }
854 
855 /*
856  * Report critical errors.  ip may be NULL.
857  */
858 void
859 hammer_critical_error(hammer_mount_t hmp, hammer_inode_t ip,
860 		      int error, const char *msg)
861 {
862 	hmp->flags |= HAMMER_MOUNT_CRITICAL_ERROR;
863 
864 	krateprintf(&hmp->krate,
865 		    "HAMMER(%s): Critical error inode=%jd error=%d %s\n",
866 		    hmp->mp->mnt_stat.f_mntfromname,
867 		    (intmax_t)(ip ? ip->obj_id : -1),
868 		    error, msg);
869 
870 	if (hmp->ronly == 0) {
871 		hmp->ronly = 2;		/* special errored read-only mode */
872 		hmp->mp->mnt_flag |= MNT_RDONLY;
873 		kprintf("HAMMER(%s): Forcing read-only mode\n",
874 			hmp->mp->mnt_stat.f_mntfromname);
875 	}
876 	hmp->error = error;
877 	if (hammer_debug_critical)
878 		Debugger("Entering debugger");
879 }
880 
881 
882 /*
883  * Obtain a vnode for the specified inode number.  An exclusively locked
884  * vnode is returned.
885  */
886 int
887 hammer_vfs_vget(struct mount *mp, struct vnode *dvp,
888 		ino_t ino, struct vnode **vpp)
889 {
890 	struct hammer_transaction trans;
891 	struct hammer_mount *hmp = (void *)mp->mnt_data;
892 	struct hammer_inode *ip;
893 	int error;
894 	u_int32_t localization;
895 
896 	hammer_simple_transaction(&trans, hmp);
897 
898 	/*
899 	 * If a directory vnode is supplied (mainly NFS) then we can acquire
900 	 * the PFS domain from it.  Otherwise we would only be able to vget
901 	 * inodes in the root PFS.
902 	 */
903 	if (dvp) {
904 		localization = HAMMER_DEF_LOCALIZATION +
905 				VTOI(dvp)->obj_localization;
906 	} else {
907 		localization = HAMMER_DEF_LOCALIZATION;
908 	}
909 
910 	/*
911 	 * Lookup the requested HAMMER inode.  The structure must be
912 	 * left unlocked while we manipulate the related vnode to avoid
913 	 * a deadlock.
914 	 */
915 	ip = hammer_get_inode(&trans, NULL, ino,
916 			      hmp->asof, localization,
917 			      0, &error);
918 	if (ip == NULL) {
919 		*vpp = NULL;
920 		hammer_done_transaction(&trans);
921 		return(error);
922 	}
923 	error = hammer_get_vnode(ip, vpp);
924 	hammer_rel_inode(ip, 0);
925 	hammer_done_transaction(&trans);
926 	return (error);
927 }
928 
929 /*
930  * Return the root vnode for the filesystem.
931  *
932  * HAMMER stores the root vnode in the hammer_mount structure so
933  * getting it is easy.
934  */
935 static int
936 hammer_vfs_root(struct mount *mp, struct vnode **vpp)
937 {
938 #if 0
939 	struct hammer_mount *hmp = (void *)mp->mnt_data;
940 #endif
941 	int error;
942 
943 	error = hammer_vfs_vget(mp, NULL, 1, vpp);
944 	return (error);
945 }
946 
947 static int
948 hammer_vfs_statfs(struct mount *mp, struct statfs *sbp, struct ucred *cred)
949 {
950 	struct hammer_mount *hmp = (void *)mp->mnt_data;
951 	hammer_volume_t volume;
952 	hammer_volume_ondisk_t ondisk;
953 	int error;
954 	int64_t bfree;
955 	int64_t breserved;
956 
957 	volume = hammer_get_root_volume(hmp, &error);
958 	if (error)
959 		return(error);
960 	ondisk = volume->ondisk;
961 
962 	/*
963 	 * Basic stats
964 	 */
965 	_hammer_checkspace(hmp, HAMMER_CHKSPC_WRITE, &breserved);
966 	mp->mnt_stat.f_files = ondisk->vol0_stat_inodes;
967 	bfree = ondisk->vol0_stat_freebigblocks * HAMMER_LARGEBLOCK_SIZE;
968 	hammer_rel_volume(volume, 0);
969 
970 	mp->mnt_stat.f_bfree = (bfree - breserved) / HAMMER_BUFSIZE;
971 	mp->mnt_stat.f_bavail = mp->mnt_stat.f_bfree;
972 	if (mp->mnt_stat.f_files < 0)
973 		mp->mnt_stat.f_files = 0;
974 
975 	*sbp = mp->mnt_stat;
976 	return(0);
977 }
978 
979 static int
980 hammer_vfs_statvfs(struct mount *mp, struct statvfs *sbp, struct ucred *cred)
981 {
982 	struct hammer_mount *hmp = (void *)mp->mnt_data;
983 	hammer_volume_t volume;
984 	hammer_volume_ondisk_t ondisk;
985 	int error;
986 	int64_t bfree;
987 	int64_t breserved;
988 
989 	volume = hammer_get_root_volume(hmp, &error);
990 	if (error)
991 		return(error);
992 	ondisk = volume->ondisk;
993 
994 	/*
995 	 * Basic stats
996 	 */
997 	_hammer_checkspace(hmp, HAMMER_CHKSPC_WRITE, &breserved);
998 	mp->mnt_vstat.f_files = ondisk->vol0_stat_inodes;
999 	bfree = ondisk->vol0_stat_freebigblocks * HAMMER_LARGEBLOCK_SIZE;
1000 	hammer_rel_volume(volume, 0);
1001 
1002 	mp->mnt_vstat.f_bfree = (bfree - breserved) / HAMMER_BUFSIZE;
1003 	mp->mnt_vstat.f_bavail = mp->mnt_vstat.f_bfree;
1004 	if (mp->mnt_vstat.f_files < 0)
1005 		mp->mnt_vstat.f_files = 0;
1006 	*sbp = mp->mnt_vstat;
1007 	return(0);
1008 }
1009 
1010 /*
1011  * Sync the filesystem.  Currently we have to run it twice, the second
1012  * one will advance the undo start index to the end index, so if a crash
1013  * occurs no undos will be run on mount.
1014  *
1015  * We do not sync the filesystem if we are called from a panic.  If we did
1016  * we might end up blowing up a sync that was already in progress.
1017  */
1018 static int
1019 hammer_vfs_sync(struct mount *mp, int waitfor)
1020 {
1021 	struct hammer_mount *hmp = (void *)mp->mnt_data;
1022 	int error;
1023 
1024 	if (panicstr == NULL) {
1025 		error = hammer_sync_hmp(hmp, waitfor);
1026 	} else {
1027 		error = EIO;
1028 	}
1029 	return (error);
1030 }
1031 
1032 /*
1033  * Convert a vnode to a file handle.
1034  */
1035 static int
1036 hammer_vfs_vptofh(struct vnode *vp, struct fid *fhp)
1037 {
1038 	hammer_inode_t ip;
1039 
1040 	KKASSERT(MAXFIDSZ >= 16);
1041 	ip = VTOI(vp);
1042 	fhp->fid_len = offsetof(struct fid, fid_data[16]);
1043 	fhp->fid_ext = ip->obj_localization >> 16;
1044 	bcopy(&ip->obj_id, fhp->fid_data + 0, sizeof(ip->obj_id));
1045 	bcopy(&ip->obj_asof, fhp->fid_data + 8, sizeof(ip->obj_asof));
1046 	return(0);
1047 }
1048 
1049 
1050 /*
1051  * Convert a file handle back to a vnode.
1052  *
1053  * Use rootvp to enforce PFS isolation when a PFS is exported via a
1054  * null mount.
1055  */
1056 static int
1057 hammer_vfs_fhtovp(struct mount *mp, struct vnode *rootvp,
1058 		  struct fid *fhp, struct vnode **vpp)
1059 {
1060 	struct hammer_transaction trans;
1061 	struct hammer_inode *ip;
1062 	struct hammer_inode_info info;
1063 	int error;
1064 	u_int32_t localization;
1065 
1066 	bcopy(fhp->fid_data + 0, &info.obj_id, sizeof(info.obj_id));
1067 	bcopy(fhp->fid_data + 8, &info.obj_asof, sizeof(info.obj_asof));
1068 	if (rootvp)
1069 		localization = VTOI(rootvp)->obj_localization;
1070 	else
1071 		localization = (u_int32_t)fhp->fid_ext << 16;
1072 
1073 	hammer_simple_transaction(&trans, (void *)mp->mnt_data);
1074 
1075 	/*
1076 	 * Get/allocate the hammer_inode structure.  The structure must be
1077 	 * unlocked while we manipulate the related vnode to avoid a
1078 	 * deadlock.
1079 	 */
1080 	ip = hammer_get_inode(&trans, NULL, info.obj_id,
1081 			      info.obj_asof, localization, 0, &error);
1082 	if (ip) {
1083 		error = hammer_get_vnode(ip, vpp);
1084 		hammer_rel_inode(ip, 0);
1085 	} else {
1086 		*vpp = NULL;
1087 	}
1088 	hammer_done_transaction(&trans);
1089 	return (error);
1090 }
1091 
1092 static int
1093 hammer_vfs_checkexp(struct mount *mp, struct sockaddr *nam,
1094 		    int *exflagsp, struct ucred **credanonp)
1095 {
1096 	hammer_mount_t hmp = (void *)mp->mnt_data;
1097 	struct netcred *np;
1098 	int error;
1099 
1100 	np = vfs_export_lookup(mp, &hmp->export, nam);
1101 	if (np) {
1102 		*exflagsp = np->netc_exflags;
1103 		*credanonp = &np->netc_anon;
1104 		error = 0;
1105 	} else {
1106 		error = EACCES;
1107 	}
1108 	return (error);
1109 
1110 }
1111 
1112 int
1113 hammer_vfs_export(struct mount *mp, int op, const struct export_args *export)
1114 {
1115 	hammer_mount_t hmp = (void *)mp->mnt_data;
1116 	int error;
1117 
1118 	switch(op) {
1119 	case MOUNTCTL_SET_EXPORT:
1120 		error = vfs_export(mp, &hmp->export, export);
1121 		break;
1122 	default:
1123 		error = EOPNOTSUPP;
1124 		break;
1125 	}
1126 	return(error);
1127 }
1128 
1129