xref: /dragonfly/sys/vfs/hammer2/hammer2_vfsops.c (revision 5ca0a96d)
1 /*
2  * Copyright (c) 2011-2018 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  * by Daniel Flores (GSOC 2013 - mentored by Matthew Dillon, compression)
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in
16  *    the documentation and/or other materials provided with the
17  *    distribution.
18  * 3. Neither the name of The DragonFly Project nor the names of its
19  *    contributors may be used to endorse or promote products derived
20  *    from this software without specific, prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
26  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/nlookup.h>
39 #include <sys/vnode.h>
40 #include <sys/mount.h>
41 #include <sys/fcntl.h>
42 #include <sys/buf.h>
43 #include <sys/uuid.h>
44 #include <sys/vfsops.h>
45 #include <sys/sysctl.h>
46 #include <sys/socket.h>
47 #include <sys/objcache.h>
48 
49 #include <sys/proc.h>
50 #include <sys/mountctl.h>
51 #include <sys/dirent.h>
52 #include <sys/uio.h>
53 
54 #include "hammer2.h"
55 #include "hammer2_disk.h"
56 #include "hammer2_mount.h"
57 #include "hammer2_lz4.h"
58 
59 #include "zlib/hammer2_zlib.h"
60 
61 #define REPORT_REFS_ERRORS 1	/* XXX remove me */
62 
63 MALLOC_DEFINE(M_OBJCACHE, "objcache", "Object Cache");
64 
65 struct hammer2_sync_info {
66 	int error;
67 	int waitfor;
68 	int pass;
69 };
70 
71 TAILQ_HEAD(hammer2_mntlist, hammer2_dev);
72 static struct hammer2_mntlist hammer2_mntlist;
73 
74 struct hammer2_pfslist hammer2_pfslist;
75 struct hammer2_pfslist hammer2_spmplist;
76 struct lock hammer2_mntlk;
77 
78 int hammer2_supported_version = HAMMER2_VOL_VERSION_DEFAULT;
79 int hammer2_debug;
80 int hammer2_xopgroups;
81 long hammer2_debug_inode;
82 int hammer2_cluster_meta_read = 1;	/* physical read-ahead */
83 int hammer2_cluster_data_read = 4;	/* physical read-ahead */
84 int hammer2_cluster_write = 0;		/* physical write clustering */
85 int hammer2_dedup_enable = 1;
86 int hammer2_always_compress = 0;	/* always try to compress */
87 int hammer2_flush_pipe = 100;
88 int hammer2_dio_count;
89 int hammer2_dio_limit = 256;
90 int hammer2_bulkfree_tps = 5000;
91 int hammer2_worker_rmask = 3;
92 long hammer2_chain_allocs;
93 long hammer2_limit_dirty_chains;
94 long hammer2_limit_dirty_inodes;
95 long hammer2_count_modified_chains;
96 long hammer2_iod_file_read;
97 long hammer2_iod_meta_read;
98 long hammer2_iod_indr_read;
99 long hammer2_iod_fmap_read;
100 long hammer2_iod_volu_read;
101 long hammer2_iod_file_write;
102 long hammer2_iod_file_wembed;
103 long hammer2_iod_file_wzero;
104 long hammer2_iod_file_wdedup;
105 long hammer2_iod_meta_write;
106 long hammer2_iod_indr_write;
107 long hammer2_iod_fmap_write;
108 long hammer2_iod_volu_write;
109 static long hammer2_iod_inode_creates;
110 static long hammer2_iod_inode_deletes;
111 
112 long hammer2_process_icrc32;
113 long hammer2_process_xxhash64;
114 
115 MALLOC_DECLARE(M_HAMMER2_CBUFFER);
116 MALLOC_DEFINE(M_HAMMER2_CBUFFER, "HAMMER2-compbuffer",
117 		"Buffer used for compression.");
118 
119 MALLOC_DECLARE(M_HAMMER2_DEBUFFER);
120 MALLOC_DEFINE(M_HAMMER2_DEBUFFER, "HAMMER2-decompbuffer",
121 		"Buffer used for decompression.");
122 
123 SYSCTL_NODE(_vfs, OID_AUTO, hammer2, CTLFLAG_RW, 0, "HAMMER2 filesystem");
124 
125 SYSCTL_INT(_vfs_hammer2, OID_AUTO, supported_version, CTLFLAG_RD,
126 	   &hammer2_supported_version, 0, "");
127 SYSCTL_INT(_vfs_hammer2, OID_AUTO, debug, CTLFLAG_RW,
128 	   &hammer2_debug, 0, "");
129 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, debug_inode, CTLFLAG_RW,
130 	   &hammer2_debug_inode, 0, "");
131 SYSCTL_INT(_vfs_hammer2, OID_AUTO, cluster_meta_read, CTLFLAG_RW,
132 	   &hammer2_cluster_meta_read, 0, "");
133 SYSCTL_INT(_vfs_hammer2, OID_AUTO, cluster_data_read, CTLFLAG_RW,
134 	   &hammer2_cluster_data_read, 0, "");
135 SYSCTL_INT(_vfs_hammer2, OID_AUTO, cluster_write, CTLFLAG_RW,
136 	   &hammer2_cluster_write, 0, "");
137 SYSCTL_INT(_vfs_hammer2, OID_AUTO, dedup_enable, CTLFLAG_RW,
138 	   &hammer2_dedup_enable, 0, "");
139 SYSCTL_INT(_vfs_hammer2, OID_AUTO, always_compress, CTLFLAG_RW,
140 	   &hammer2_always_compress, 0, "");
141 SYSCTL_INT(_vfs_hammer2, OID_AUTO, flush_pipe, CTLFLAG_RW,
142 	   &hammer2_flush_pipe, 0, "");
143 SYSCTL_INT(_vfs_hammer2, OID_AUTO, worker_rmask, CTLFLAG_RW,
144 	   &hammer2_worker_rmask, 0, "");
145 SYSCTL_INT(_vfs_hammer2, OID_AUTO, bulkfree_tps, CTLFLAG_RW,
146 	   &hammer2_bulkfree_tps, 0, "");
147 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, chain_allocs, CTLFLAG_RW,
148 	   &hammer2_chain_allocs, 0, "");
149 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, limit_dirty_chains, CTLFLAG_RW,
150 	   &hammer2_limit_dirty_chains, 0, "");
151 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, limit_dirty_inodes, CTLFLAG_RW,
152 	   &hammer2_limit_dirty_inodes, 0, "");
153 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, count_modified_chains, CTLFLAG_RW,
154 	   &hammer2_count_modified_chains, 0, "");
155 SYSCTL_INT(_vfs_hammer2, OID_AUTO, dio_count, CTLFLAG_RD,
156 	   &hammer2_dio_count, 0, "");
157 SYSCTL_INT(_vfs_hammer2, OID_AUTO, dio_limit, CTLFLAG_RW,
158 	   &hammer2_dio_limit, 0, "");
159 
160 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_read, CTLFLAG_RW,
161 	   &hammer2_iod_file_read, 0, "");
162 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_meta_read, CTLFLAG_RW,
163 	   &hammer2_iod_meta_read, 0, "");
164 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_indr_read, CTLFLAG_RW,
165 	   &hammer2_iod_indr_read, 0, "");
166 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_fmap_read, CTLFLAG_RW,
167 	   &hammer2_iod_fmap_read, 0, "");
168 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_volu_read, CTLFLAG_RW,
169 	   &hammer2_iod_volu_read, 0, "");
170 
171 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_write, CTLFLAG_RW,
172 	   &hammer2_iod_file_write, 0, "");
173 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_wembed, CTLFLAG_RW,
174 	   &hammer2_iod_file_wembed, 0, "");
175 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_wzero, CTLFLAG_RW,
176 	   &hammer2_iod_file_wzero, 0, "");
177 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_wdedup, CTLFLAG_RW,
178 	   &hammer2_iod_file_wdedup, 0, "");
179 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_meta_write, CTLFLAG_RW,
180 	   &hammer2_iod_meta_write, 0, "");
181 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_indr_write, CTLFLAG_RW,
182 	   &hammer2_iod_indr_write, 0, "");
183 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_fmap_write, CTLFLAG_RW,
184 	   &hammer2_iod_fmap_write, 0, "");
185 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_volu_write, CTLFLAG_RW,
186 	   &hammer2_iod_volu_write, 0, "");
187 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_inode_creates, CTLFLAG_RW,
188 	   &hammer2_iod_inode_creates, 0, "");
189 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_inode_deletes, CTLFLAG_RW,
190 	   &hammer2_iod_inode_deletes, 0, "");
191 
192 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, process_icrc32, CTLFLAG_RW,
193 	   &hammer2_process_icrc32, 0, "");
194 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, process_xxhash64, CTLFLAG_RW,
195 	   &hammer2_process_xxhash64, 0, "");
196 
197 static int hammer2_vfs_init(struct vfsconf *conf);
198 static int hammer2_vfs_uninit(struct vfsconf *vfsp);
199 static int hammer2_vfs_mount(struct mount *mp, char *path, caddr_t data,
200 				struct ucred *cred);
201 static int hammer2_remount(hammer2_dev_t *, struct mount *, char *,
202 				struct ucred *);
203 static int hammer2_recovery(hammer2_dev_t *hmp);
204 static int hammer2_vfs_unmount(struct mount *mp, int mntflags);
205 static int hammer2_vfs_root(struct mount *mp, struct vnode **vpp);
206 static int hammer2_vfs_statfs(struct mount *mp, struct statfs *sbp,
207 				struct ucred *cred);
208 static int hammer2_vfs_statvfs(struct mount *mp, struct statvfs *sbp,
209 				struct ucred *cred);
210 static int hammer2_vfs_fhtovp(struct mount *mp, struct vnode *rootvp,
211 				struct fid *fhp, struct vnode **vpp);
212 static int hammer2_vfs_vptofh(struct vnode *vp, struct fid *fhp);
213 static int hammer2_vfs_checkexp(struct mount *mp, struct sockaddr *nam,
214 				int *exflagsp, struct ucred **credanonp);
215 static int hammer2_vfs_modifying(struct mount *mp);
216 
217 static void hammer2_update_pmps(hammer2_dev_t *hmp);
218 
219 static void hammer2_mount_helper(struct mount *mp, hammer2_pfs_t *pmp);
220 static void hammer2_unmount_helper(struct mount *mp, hammer2_pfs_t *pmp,
221 				hammer2_dev_t *hmp);
222 static int hammer2_fixup_pfses(hammer2_dev_t *hmp);
223 
224 /*
225  * HAMMER2 vfs operations.
226  */
227 static struct vfsops hammer2_vfsops = {
228 	.vfs_flags	= 0,
229 	.vfs_init	= hammer2_vfs_init,
230 	.vfs_uninit	= hammer2_vfs_uninit,
231 	.vfs_sync	= hammer2_vfs_sync,
232 	.vfs_mount	= hammer2_vfs_mount,
233 	.vfs_unmount	= hammer2_vfs_unmount,
234 	.vfs_root 	= hammer2_vfs_root,
235 	.vfs_statfs	= hammer2_vfs_statfs,
236 	.vfs_statvfs	= hammer2_vfs_statvfs,
237 	.vfs_vget	= hammer2_vfs_vget,
238 	.vfs_vptofh	= hammer2_vfs_vptofh,
239 	.vfs_fhtovp	= hammer2_vfs_fhtovp,
240 	.vfs_checkexp	= hammer2_vfs_checkexp,
241 	.vfs_modifying	= hammer2_vfs_modifying
242 };
243 
244 MALLOC_DEFINE(M_HAMMER2, "HAMMER2-mount", "");
245 
246 VFS_SET(hammer2_vfsops, hammer2, VFCF_MPSAFE);
247 MODULE_VERSION(hammer2, 1);
248 
249 static
250 int
251 hammer2_vfs_init(struct vfsconf *conf)
252 {
253 	static struct objcache_malloc_args margs_read;
254 	static struct objcache_malloc_args margs_write;
255 	static struct objcache_malloc_args margs_vop;
256 
257 	int error;
258 
259 	error = 0;
260 	kmalloc_raise_limit(M_HAMMER2, 0);	/* unlimited */
261 
262 	/*
263 	 * hammer2_xopgroups must be even and is most optimal if
264 	 * 2 x ncpus so strategy functions can be queued to the same
265 	 * cpu.
266 	 */
267 	hammer2_xopgroups = HAMMER2_XOPGROUPS_MIN;
268 	if (hammer2_xopgroups < ncpus * 2)
269 		hammer2_xopgroups = ncpus * 2;
270 
271 	/*
272 	 * A large DIO cache is needed to retain dedup enablement masks.
273 	 * The bulkfree code clears related masks as part of the disk block
274 	 * recycling algorithm, preventing it from being used for a later
275 	 * dedup.
276 	 *
277 	 * NOTE: A large buffer cache can actually interfere with dedup
278 	 *	 operation because we dedup based on media physical buffers
279 	 *	 and not logical buffers.  Try to make the DIO case large
280 	 *	 enough to avoid this problem, but also cap it.
281 	 */
282 	hammer2_dio_limit = nbuf * 2;
283 	if (hammer2_dio_limit > 100000)
284 		hammer2_dio_limit = 100000;
285 
286 	if (HAMMER2_BLOCKREF_BYTES != sizeof(struct hammer2_blockref))
287 		error = EINVAL;
288 	if (HAMMER2_INODE_BYTES != sizeof(struct hammer2_inode_data))
289 		error = EINVAL;
290 	if (HAMMER2_VOLUME_BYTES != sizeof(struct hammer2_volume_data))
291 		error = EINVAL;
292 
293 	if (error)
294 		kprintf("HAMMER2 structure size mismatch; cannot continue.\n");
295 
296 	margs_read.objsize = 65536;
297 	margs_read.mtype = M_HAMMER2_DEBUFFER;
298 
299 	margs_write.objsize = 32768;
300 	margs_write.mtype = M_HAMMER2_CBUFFER;
301 
302 	margs_vop.objsize = sizeof(hammer2_xop_t);
303 	margs_vop.mtype = M_HAMMER2;
304 
305 	/*
306 	 * Note thaht for the XOPS cache we want backing store allocations
307 	 * to use M_ZERO.  This is not allowed in objcache_get() (to avoid
308 	 * confusion), so use the backing store function that does it.  This
309 	 * means that initial XOPS objects are zerod but REUSED objects are
310 	 * not.  So we are responsible for cleaning the object up sufficiently
311 	 * for our needs before objcache_put()ing it back (typically just the
312 	 * FIFO indices).
313 	 */
314 	cache_buffer_read = objcache_create(margs_read.mtype->ks_shortdesc,
315 				0, 1, NULL, NULL, NULL,
316 				objcache_malloc_alloc,
317 				objcache_malloc_free,
318 				&margs_read);
319 	cache_buffer_write = objcache_create(margs_write.mtype->ks_shortdesc,
320 				0, 1, NULL, NULL, NULL,
321 				objcache_malloc_alloc,
322 				objcache_malloc_free,
323 				&margs_write);
324 	cache_xops = objcache_create(margs_vop.mtype->ks_shortdesc,
325 				0, 1, NULL, NULL, NULL,
326 				objcache_malloc_alloc_zero,
327 				objcache_malloc_free,
328 				&margs_vop);
329 
330 
331 	lockinit(&hammer2_mntlk, "mntlk", 0, 0);
332 	TAILQ_INIT(&hammer2_mntlist);
333 	TAILQ_INIT(&hammer2_pfslist);
334 	TAILQ_INIT(&hammer2_spmplist);
335 
336 	hammer2_limit_dirty_chains = maxvnodes / 10;
337 	if (hammer2_limit_dirty_chains > HAMMER2_LIMIT_DIRTY_CHAINS)
338 		hammer2_limit_dirty_chains = HAMMER2_LIMIT_DIRTY_CHAINS;
339 	if (hammer2_limit_dirty_chains < 1000)
340 		hammer2_limit_dirty_chains = 1000;
341 
342 	hammer2_limit_dirty_inodes = maxvnodes / 25;
343 	if (hammer2_limit_dirty_inodes < 100)
344 		hammer2_limit_dirty_inodes = 100;
345 	if (hammer2_limit_dirty_inodes > HAMMER2_LIMIT_DIRTY_INODES)
346 		hammer2_limit_dirty_inodes = HAMMER2_LIMIT_DIRTY_INODES;
347 
348 	return (error);
349 }
350 
351 static
352 int
353 hammer2_vfs_uninit(struct vfsconf *vfsp __unused)
354 {
355 	objcache_destroy(cache_buffer_read);
356 	objcache_destroy(cache_buffer_write);
357 	objcache_destroy(cache_xops);
358 	return 0;
359 }
360 
361 /*
362  * Core PFS allocator.  Used to allocate or reference the pmp structure
363  * for PFS cluster mounts and the spmp structure for media (hmp) structures.
364  * The pmp can be passed in or loaded by this function using the chain and
365  * inode data.
366  *
367  * pmp->modify_tid tracks new modify_tid transaction ids for front-end
368  * transactions.  Note that synchronization does not use this field.
369  * (typically frontend operations and synchronization cannot run on the
370  * same PFS node at the same time).
371  *
372  * XXX check locking
373  */
374 hammer2_pfs_t *
375 hammer2_pfsalloc(hammer2_chain_t *chain,
376 		 const hammer2_inode_data_t *ripdata,
377 		 hammer2_tid_t modify_tid, hammer2_dev_t *force_local)
378 {
379 	hammer2_pfs_t *pmp;
380 	hammer2_inode_t *iroot;
381 	int count;
382 	int i;
383 	int j;
384 
385 	pmp = NULL;
386 
387 	/*
388 	 * Locate or create the PFS based on the cluster id.  If ripdata
389 	 * is NULL this is a spmp which is unique and is always allocated.
390 	 *
391 	 * If the device is mounted in local mode all PFSs are considered
392 	 * independent and not part of any cluster (for debugging only).
393 	 */
394 	if (ripdata) {
395 		TAILQ_FOREACH(pmp, &hammer2_pfslist, mntentry) {
396 			if (force_local != pmp->force_local)
397 				continue;
398 			if (force_local == NULL &&
399 			    bcmp(&pmp->pfs_clid, &ripdata->meta.pfs_clid,
400 				 sizeof(pmp->pfs_clid)) == 0) {
401 					break;
402 			} else if (force_local && pmp->pfs_names[0] &&
403 			    strcmp(pmp->pfs_names[0], ripdata->filename) == 0) {
404 					break;
405 			}
406 		}
407 	}
408 
409 	if (pmp == NULL) {
410 		pmp = kmalloc(sizeof(*pmp), M_HAMMER2, M_WAITOK | M_ZERO);
411 		pmp->force_local = force_local;
412 		hammer2_trans_manage_init(pmp);
413 		kmalloc_create(&pmp->minode, "HAMMER2-inodes");
414 		kmalloc_create(&pmp->mmsg, "HAMMER2-pfsmsg");
415 		lockinit(&pmp->lock, "pfslk", 0, 0);
416 		lockinit(&pmp->lock_nlink, "h2nlink", 0, 0);
417 		spin_init(&pmp->inum_spin, "hm2pfsalloc_inum");
418 		spin_init(&pmp->xop_spin, "h2xop");
419 		spin_init(&pmp->lru_spin, "h2lru");
420 		RB_INIT(&pmp->inum_tree);
421 		TAILQ_INIT(&pmp->syncq);
422 		TAILQ_INIT(&pmp->depq);
423 		TAILQ_INIT(&pmp->lru_list);
424 		spin_init(&pmp->list_spin, "h2pfsalloc_list");
425 
426 		/*
427 		 * Save the last media transaction id for the flusher.  Set
428 		 * initial
429 		 */
430 		if (ripdata) {
431 			pmp->pfs_clid = ripdata->meta.pfs_clid;
432 			TAILQ_INSERT_TAIL(&hammer2_pfslist, pmp, mntentry);
433 		} else {
434 			pmp->flags |= HAMMER2_PMPF_SPMP;
435 			TAILQ_INSERT_TAIL(&hammer2_spmplist, pmp, mntentry);
436 		}
437 
438 		/*
439 		 * The synchronization thread may start too early, make
440 		 * sure it stays frozen until we are ready to let it go.
441 		 * XXX
442 		 */
443 		/*
444 		pmp->primary_thr.flags = HAMMER2_THREAD_FROZEN |
445 					 HAMMER2_THREAD_REMASTER;
446 		*/
447 	}
448 
449 	/*
450 	 * Create the PFS's root inode and any missing XOP helper threads.
451 	 */
452 	if ((iroot = pmp->iroot) == NULL) {
453 		iroot = hammer2_inode_get(pmp, NULL, 1, -1);
454 		if (ripdata)
455 			iroot->meta = ripdata->meta;
456 		pmp->iroot = iroot;
457 		hammer2_inode_ref(iroot);
458 		hammer2_inode_unlock(iroot);
459 	}
460 
461 	/*
462 	 * Stop here if no chain is passed in.
463 	 */
464 	if (chain == NULL)
465 		goto done;
466 
467 	/*
468 	 * When a chain is passed in we must add it to the PFS's root
469 	 * inode, update pmp->pfs_types[], and update the syncronization
470 	 * threads.
471 	 *
472 	 * When forcing local mode, mark the PFS as a MASTER regardless.
473 	 *
474 	 * At the moment empty spots can develop due to removals or failures.
475 	 * Ultimately we want to re-fill these spots but doing so might
476 	 * confused running code. XXX
477 	 */
478 	hammer2_inode_ref(iroot);
479 	hammer2_mtx_ex(&iroot->lock);
480 	j = iroot->cluster.nchains;
481 
482 	if (j == HAMMER2_MAXCLUSTER) {
483 		kprintf("hammer2_pfsalloc: cluster full!\n");
484 		/* XXX fatal error? */
485 	} else {
486 		KKASSERT(chain->pmp == NULL);
487 		chain->pmp = pmp;
488 		hammer2_chain_ref(chain);
489 		iroot->cluster.array[j].chain = chain;
490 		if (force_local)
491 			pmp->pfs_types[j] = HAMMER2_PFSTYPE_MASTER;
492 		else
493 			pmp->pfs_types[j] = ripdata->meta.pfs_type;
494 		pmp->pfs_names[j] = kstrdup(ripdata->filename, M_HAMMER2);
495 		pmp->pfs_hmps[j] = chain->hmp;
496 		hammer2_spin_ex(&pmp->inum_spin);
497 		pmp->pfs_iroot_blocksets[j] = chain->data->ipdata.u.blockset;
498 		hammer2_spin_unex(&pmp->inum_spin);
499 
500 		/*
501 		 * If the PFS is already mounted we must account
502 		 * for the mount_count here.
503 		 */
504 		if (pmp->mp)
505 			++chain->hmp->mount_count;
506 
507 		/*
508 		 * May have to fixup dirty chain tracking.  Previous
509 		 * pmp was NULL so nothing to undo.
510 		 */
511 		if (chain->flags & HAMMER2_CHAIN_MODIFIED)
512 			hammer2_pfs_memory_inc(pmp);
513 		++j;
514 	}
515 	iroot->cluster.nchains = j;
516 
517 	/*
518 	 * Update nmasters from any PFS inode which is part of the cluster.
519 	 * It is possible that this will result in a value which is too
520 	 * high.  MASTER PFSs are authoritative for pfs_nmasters and will
521 	 * override this value later on.
522 	 *
523 	 * (This informs us of masters that might not currently be
524 	 *  discoverable by this mount).
525 	 */
526 	if (ripdata && pmp->pfs_nmasters < ripdata->meta.pfs_nmasters) {
527 		pmp->pfs_nmasters = ripdata->meta.pfs_nmasters;
528 	}
529 
530 	/*
531 	 * Count visible masters.  Masters are usually added with
532 	 * ripdata->meta.pfs_nmasters set to 1.  This detects when there
533 	 * are more (XXX and must update the master inodes).
534 	 */
535 	count = 0;
536 	for (i = 0; i < iroot->cluster.nchains; ++i) {
537 		if (pmp->pfs_types[i] == HAMMER2_PFSTYPE_MASTER)
538 			++count;
539 	}
540 	if (pmp->pfs_nmasters < count)
541 		pmp->pfs_nmasters = count;
542 
543 	/*
544 	 * Create missing synchronization and support threads.
545 	 *
546 	 * Single-node masters (including snapshots) have nothing to
547 	 * synchronize and do not require this thread.
548 	 *
549 	 * Multi-node masters or any number of soft masters, slaves, copy,
550 	 * or other PFS types need the thread.
551 	 *
552 	 * Each thread is responsible for its particular cluster index.
553 	 * We use independent threads so stalls or mismatches related to
554 	 * any given target do not affect other targets.
555 	 */
556 	for (i = 0; i < iroot->cluster.nchains; ++i) {
557 		/*
558 		 * Single-node masters (including snapshots) have nothing
559 		 * to synchronize and will make direct xops support calls,
560 		 * thus they do not require this thread.
561 		 *
562 		 * Note that there can be thousands of snapshots.  We do not
563 		 * want to create thousands of threads.
564 		 */
565 		if (pmp->pfs_nmasters <= 1 &&
566 		    pmp->pfs_types[i] == HAMMER2_PFSTYPE_MASTER) {
567 			continue;
568 		}
569 
570 		/*
571 		 * Sync support thread
572 		 */
573 		if (pmp->sync_thrs[i].td == NULL) {
574 			hammer2_thr_create(&pmp->sync_thrs[i], pmp, NULL,
575 					   "h2nod", i, -1,
576 					   hammer2_primary_sync_thread);
577 		}
578 	}
579 
580 	/*
581 	 * Create missing Xop threads
582 	 *
583 	 * NOTE: We create helper threads for all mounted PFSs or any
584 	 *	 PFSs with 2+ nodes (so the sync thread can update them,
585 	 *	 even if not mounted).
586 	 */
587 	if (pmp->mp || iroot->cluster.nchains >= 2)
588 		hammer2_xop_helper_create(pmp);
589 
590 	hammer2_mtx_unlock(&iroot->lock);
591 	hammer2_inode_drop(iroot);
592 done:
593 	return pmp;
594 }
595 
596 /*
597  * Deallocate an element of a probed PFS.  If destroying and this is a
598  * MASTER, adjust nmasters.
599  *
600  * This function does not physically destroy the PFS element in its device
601  * under the super-root  (see hammer2_ioctl_pfs_delete()).
602  */
603 void
604 hammer2_pfsdealloc(hammer2_pfs_t *pmp, int clindex, int destroying)
605 {
606 	hammer2_inode_t *iroot;
607 	hammer2_chain_t *chain;
608 	int j;
609 
610 	/*
611 	 * Cleanup our reference on iroot.  iroot is (should) not be needed
612 	 * by the flush code.
613 	 */
614 	iroot = pmp->iroot;
615 	if (iroot) {
616 		/*
617 		 * Stop synchronizing
618 		 *
619 		 * XXX flush after acquiring the iroot lock.
620 		 * XXX clean out the cluster index from all inode structures.
621 		 */
622 		hammer2_thr_delete(&pmp->sync_thrs[clindex]);
623 
624 		/*
625 		 * Remove the cluster index from the group.  If destroying
626 		 * the PFS and this is a master, adjust pfs_nmasters.
627 		 */
628 		hammer2_mtx_ex(&iroot->lock);
629 		chain = iroot->cluster.array[clindex].chain;
630 		iroot->cluster.array[clindex].chain = NULL;
631 
632 		switch(pmp->pfs_types[clindex]) {
633 		case HAMMER2_PFSTYPE_MASTER:
634 			if (destroying && pmp->pfs_nmasters > 0)
635 				--pmp->pfs_nmasters;
636 			/* XXX adjust ripdata->meta.pfs_nmasters */
637 			break;
638 		default:
639 			break;
640 		}
641 		pmp->pfs_types[clindex] = HAMMER2_PFSTYPE_NONE;
642 
643 		hammer2_mtx_unlock(&iroot->lock);
644 
645 		/*
646 		 * Release the chain.
647 		 */
648 		if (chain) {
649 			atomic_set_int(&chain->flags, HAMMER2_CHAIN_RELEASE);
650 			hammer2_chain_drop(chain);
651 		}
652 
653 		/*
654 		 * Terminate all XOP threads for the cluster index.
655 		 */
656 		if (pmp->xop_groups) {
657 			for (j = 0; j < hammer2_xopgroups; ++j) {
658 				hammer2_thr_delete(
659 					&pmp->xop_groups[j].thrs[clindex]);
660 			}
661 		}
662 	}
663 }
664 
665 /*
666  * Destroy a PFS, typically only occurs after the last mount on a device
667  * has gone away.
668  */
669 static void
670 hammer2_pfsfree(hammer2_pfs_t *pmp)
671 {
672 	hammer2_inode_t *iroot;
673 	hammer2_chain_t *chain;
674 	int chains_still_present = 0;
675 	int i;
676 	int j;
677 
678 	/*
679 	 * Cleanup our reference on iroot.  iroot is (should) not be needed
680 	 * by the flush code.
681 	 */
682 	if (pmp->flags & HAMMER2_PMPF_SPMP)
683 		TAILQ_REMOVE(&hammer2_spmplist, pmp, mntentry);
684 	else
685 		TAILQ_REMOVE(&hammer2_pfslist, pmp, mntentry);
686 
687 	/*
688 	 * Cleanup chains remaining on LRU list.
689 	 */
690 	hammer2_spin_ex(&pmp->lru_spin);
691 	while ((chain = TAILQ_FIRST(&pmp->lru_list)) != NULL) {
692 		KKASSERT(chain->flags & HAMMER2_CHAIN_ONLRU);
693 		atomic_add_int(&pmp->lru_count, -1);
694 		atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONLRU);
695 		TAILQ_REMOVE(&pmp->lru_list, chain, lru_node);
696 		hammer2_chain_ref(chain);
697 		hammer2_spin_unex(&pmp->lru_spin);
698 		atomic_set_int(&chain->flags, HAMMER2_CHAIN_RELEASE);
699 		hammer2_chain_drop(chain);
700 		hammer2_spin_ex(&pmp->lru_spin);
701 	}
702 	hammer2_spin_unex(&pmp->lru_spin);
703 
704 	/*
705 	 * Clean up iroot
706 	 */
707 	iroot = pmp->iroot;
708 	if (iroot) {
709 		for (i = 0; i < iroot->cluster.nchains; ++i) {
710 			hammer2_thr_delete(&pmp->sync_thrs[i]);
711 			if (pmp->xop_groups) {
712 				for (j = 0; j < hammer2_xopgroups; ++j)
713 					hammer2_thr_delete(
714 						&pmp->xop_groups[j].thrs[i]);
715 			}
716 			chain = iroot->cluster.array[i].chain;
717 			if (chain && !RB_EMPTY(&chain->core.rbtree)) {
718 				kprintf("hammer2: Warning pmp %p still "
719 					"has active chains\n", pmp);
720 				chains_still_present = 1;
721 			}
722 		}
723 #if REPORT_REFS_ERRORS
724 		if (iroot->refs != 1)
725 			kprintf("PMP->IROOT %p REFS WRONG %d\n",
726 				iroot, iroot->refs);
727 #else
728 		KKASSERT(iroot->refs == 1);
729 #endif
730 		/* ref for iroot */
731 		hammer2_inode_drop(iroot);
732 		pmp->iroot = NULL;
733 	}
734 
735 	/*
736 	 * Free remaining pmp resources
737 	 */
738 	if (chains_still_present) {
739 		kprintf("hammer2: cannot free pmp %p, still in use\n", pmp);
740 	} else {
741 		kmalloc_destroy(&pmp->mmsg);
742 		kmalloc_destroy(&pmp->minode);
743 		kfree(pmp, M_HAMMER2);
744 	}
745 }
746 
747 /*
748  * Remove all references to hmp from the pfs list.  Any PFS which becomes
749  * empty is terminated and freed.
750  *
751  * XXX inefficient.
752  */
753 static void
754 hammer2_pfsfree_scan(hammer2_dev_t *hmp, int which)
755 {
756 	hammer2_pfs_t *pmp;
757 	hammer2_inode_t *iroot;
758 	hammer2_chain_t *rchain;
759 	int i;
760 	int j;
761 	struct hammer2_pfslist *wlist;
762 
763 	if (which == 0)
764 		wlist = &hammer2_pfslist;
765 	else
766 		wlist = &hammer2_spmplist;
767 again:
768 	TAILQ_FOREACH(pmp, wlist, mntentry) {
769 		if ((iroot = pmp->iroot) == NULL)
770 			continue;
771 
772 		/*
773 		 * Determine if this PFS is affected.  If it is we must
774 		 * freeze all management threads and lock its iroot.
775 		 *
776 		 * Freezing a management thread forces it idle, operations
777 		 * in-progress will be aborted and it will have to start
778 		 * over again when unfrozen, or exit if told to exit.
779 		 */
780 		for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
781 			if (pmp->pfs_hmps[i] == hmp)
782 				break;
783 		}
784 		if (i == HAMMER2_MAXCLUSTER)
785 			continue;
786 
787 		hammer2_vfs_sync_pmp(pmp, MNT_WAIT);
788 
789 		/*
790 		 * Make sure all synchronization threads are locked
791 		 * down.
792 		 */
793 		for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
794 			if (pmp->pfs_hmps[i] == NULL)
795 				continue;
796 			hammer2_thr_freeze_async(&pmp->sync_thrs[i]);
797 			if (pmp->xop_groups) {
798 				for (j = 0; j < hammer2_xopgroups; ++j) {
799 					hammer2_thr_freeze_async(
800 						&pmp->xop_groups[j].thrs[i]);
801 				}
802 			}
803 		}
804 		for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
805 			if (pmp->pfs_hmps[i] == NULL)
806 				continue;
807 			hammer2_thr_freeze(&pmp->sync_thrs[i]);
808 			if (pmp->xop_groups) {
809 				for (j = 0; j < hammer2_xopgroups; ++j) {
810 					hammer2_thr_freeze(
811 						&pmp->xop_groups[j].thrs[i]);
812 				}
813 			}
814 		}
815 
816 		/*
817 		 * Lock the inode and clean out matching chains.
818 		 * Note that we cannot use hammer2_inode_lock_*()
819 		 * here because that would attempt to validate the
820 		 * cluster that we are in the middle of ripping
821 		 * apart.
822 		 *
823 		 * WARNING! We are working directly on the inodes
824 		 *	    embedded cluster.
825 		 */
826 		hammer2_mtx_ex(&iroot->lock);
827 
828 		/*
829 		 * Remove the chain from matching elements of the PFS.
830 		 */
831 		for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
832 			if (pmp->pfs_hmps[i] != hmp)
833 				continue;
834 			hammer2_thr_delete(&pmp->sync_thrs[i]);
835 			if (pmp->xop_groups) {
836 				for (j = 0; j < hammer2_xopgroups; ++j) {
837 					hammer2_thr_delete(
838 						&pmp->xop_groups[j].thrs[i]);
839 				}
840 			}
841 			rchain = iroot->cluster.array[i].chain;
842 			iroot->cluster.array[i].chain = NULL;
843 			pmp->pfs_types[i] = 0;
844 			if (pmp->pfs_names[i]) {
845 				kfree(pmp->pfs_names[i], M_HAMMER2);
846 				pmp->pfs_names[i] = NULL;
847 			}
848 			if (rchain) {
849 				hammer2_chain_drop(rchain);
850 				/* focus hint */
851 				if (iroot->cluster.focus == rchain)
852 					iroot->cluster.focus = NULL;
853 			}
854 			pmp->pfs_hmps[i] = NULL;
855 		}
856 		hammer2_mtx_unlock(&iroot->lock);
857 
858 		/*
859 		 * Cleanup trailing chains.  Gaps may remain.
860 		 */
861 		for (i = HAMMER2_MAXCLUSTER - 1; i >= 0; --i) {
862 			if (pmp->pfs_hmps[i])
863 				break;
864 		}
865 		iroot->cluster.nchains = i + 1;
866 
867 		/*
868 		 * If the PMP has no elements remaining we can destroy it.
869 		 * (this will transition management threads from frozen->exit).
870 		 */
871 		if (iroot->cluster.nchains == 0) {
872 			/*
873 			 * If this was the hmp's spmp, we need to clean
874 			 * a little more stuff out.
875 			 */
876 			if (hmp->spmp == pmp) {
877 				hmp->spmp = NULL;
878 				hmp->vchain.pmp = NULL;
879 				hmp->fchain.pmp = NULL;
880 			}
881 
882 			/*
883 			 * Free the pmp and restart the loop
884 			 */
885 			KKASSERT(TAILQ_EMPTY(&pmp->syncq));
886 			KKASSERT(TAILQ_EMPTY(&pmp->depq));
887 			hammer2_pfsfree(pmp);
888 			goto again;
889 		}
890 
891 		/*
892 		 * If elements still remain we need to set the REMASTER
893 		 * flag and unfreeze it.
894 		 */
895 		for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
896 			if (pmp->pfs_hmps[i] == NULL)
897 				continue;
898 			hammer2_thr_remaster(&pmp->sync_thrs[i]);
899 			hammer2_thr_unfreeze(&pmp->sync_thrs[i]);
900 			if (pmp->xop_groups) {
901 				for (j = 0; j < hammer2_xopgroups; ++j) {
902 					hammer2_thr_remaster(
903 						&pmp->xop_groups[j].thrs[i]);
904 					hammer2_thr_unfreeze(
905 						&pmp->xop_groups[j].thrs[i]);
906 				}
907 			}
908 		}
909 	}
910 }
911 
912 /*
913  * Mount or remount HAMMER2 fileystem from physical media
914  *
915  *	mountroot
916  *		mp		mount point structure
917  *		path		NULL
918  *		data		<unused>
919  *		cred		<unused>
920  *
921  *	mount
922  *		mp		mount point structure
923  *		path		path to mount point
924  *		data		pointer to argument structure in user space
925  *			volume	volume path (device@LABEL form)
926  *			hflags	user mount flags
927  *		cred		user credentials
928  *
929  * RETURNS:	0	Success
930  *		!0	error number
931  */
932 static
933 int
934 hammer2_vfs_mount(struct mount *mp, char *path, caddr_t data,
935 		  struct ucred *cred)
936 {
937 	struct hammer2_mount_info info;
938 	hammer2_pfs_t *pmp;
939 	hammer2_pfs_t *spmp;
940 	hammer2_dev_t *hmp, *hmp_tmp;
941 	hammer2_dev_t *force_local;
942 	hammer2_key_t key_next;
943 	hammer2_key_t key_dummy;
944 	hammer2_key_t lhc;
945 	hammer2_chain_t *parent;
946 	hammer2_chain_t *chain;
947 	const hammer2_inode_data_t *ripdata;
948 	hammer2_blockref_t bref;
949 	hammer2_devvp_list_t devvpl;
950 	hammer2_devvp_t *e, *e_tmp;
951 	struct file *fp;
952 	char devstr[MNAMELEN];
953 	size_t size;
954 	size_t done;
955 	char *dev;
956 	char *label;
957 	int ronly = ((mp->mnt_flag & MNT_RDONLY) != 0);
958 	int error;
959 	int i;
960 
961 	hmp = NULL;
962 	pmp = NULL;
963 	dev = NULL;
964 	label = NULL;
965 	bzero(&info, sizeof(info));
966 
967 	if (path) {
968 		/*
969 		 * Non-root mount or updating a mount
970 		 */
971 		error = copyin(data, &info, sizeof(info));
972 		if (error)
973 			return (error);
974 	}
975 
976 	if (mp->mnt_flag & MNT_UPDATE) {
977 		/*
978 		 * Update mount.  Note that pmp->iroot->cluster is
979 		 * an inode-embedded cluster and thus cannot be
980 		 * directly locked.
981 		 *
982 		 * XXX HAMMER2 needs to implement NFS export via
983 		 *     mountctl.
984 		 */
985 		hammer2_cluster_t *cluster;
986 
987 		pmp = MPTOPMP(mp);
988 		pmp->hflags = info.hflags;
989 		cluster = &pmp->iroot->cluster;
990 		for (i = 0; i < cluster->nchains; ++i) {
991 			if (cluster->array[i].chain == NULL)
992 				continue;
993 			hmp = cluster->array[i].chain->hmp;
994 			error = hammer2_remount(hmp, mp, path, cred);
995 			if (error)
996 				break;
997 		}
998 
999 		return error;
1000 	}
1001 
1002 	if (path == NULL) {
1003 		/*
1004 		 * Root mount
1005 		 */
1006 		info.cluster_fd = -1;
1007 		ksnprintf(devstr, sizeof(devstr), "%s",
1008 			  mp->mnt_stat.f_mntfromname);
1009 		done = strlen(devstr) + 1;
1010 		kprintf("hammer2_mount: root devstr=\"%s\"\n", devstr);
1011 	} else {
1012 		error = copyinstr(info.volume, devstr, MNAMELEN - 1, &done);
1013 		if (error)
1014 			return (error);
1015 		kprintf("hammer2_mount: devstr=\"%s\"\n", devstr);
1016 	}
1017 
1018 	/*
1019 	 * Extract device and label, automatically mount @BOOT, @ROOT, or @DATA
1020 	 * if no label specified, based on the partition id.  Error out if no
1021 	 * label or device (with partition id) is specified.  This is strictly
1022 	 * a convenience to match the default label created by newfs_hammer2,
1023 	 * our preference is that a label always be specified.
1024 	 *
1025 	 * NOTE: We allow 'mount @LABEL <blah>'... that is, a mount command
1026 	 *	 that does not specify a device, as long as some H2 label
1027 	 *	 has already been mounted from that device.  This makes
1028 	 *	 mounting snapshots a lot easier.
1029 	 */
1030 	dev = devstr;
1031 	label = strchr(devstr, '@');
1032 	if (label && ((label + 1) - dev) > done) {
1033 		kprintf("hammer2_mount: bad label %s/%zd\n", devstr, done);
1034 		return (EINVAL);
1035 	}
1036 	if (label == NULL || label[1] == 0) {
1037 		char slice;
1038 
1039 		if (label == NULL)
1040 			label = devstr + strlen(devstr);
1041 		else
1042 			*label = '\0';		/* clean up trailing @ */
1043 
1044 		slice = label[-1];
1045 		switch(slice) {
1046 		case 'a':
1047 			label = "BOOT";
1048 			break;
1049 		case 'd':
1050 			label = "ROOT";
1051 			break;
1052 		default:
1053 			label = "DATA";
1054 			break;
1055 		}
1056 	} else {
1057 		*label = '\0';
1058 		label++;
1059 	}
1060 
1061 	kprintf("hammer2_mount: dev=\"%s\" label=\"%s\" rdonly=%d\n",
1062 		dev, label, ronly);
1063 
1064 	/*
1065 	 * Initialize all device vnodes.
1066 	 */
1067 	TAILQ_INIT(&devvpl);
1068 	error = hammer2_init_devvp(dev, path == NULL, &devvpl);
1069 	if (error) {
1070 		kprintf("hammer2: failed to initialize devvp in %s\n", dev);
1071 		hammer2_cleanup_devvp(&devvpl);
1072 		return error;
1073 	}
1074 
1075 	/*
1076 	 * Determine if the device has already been mounted.  After this
1077 	 * check hmp will be non-NULL if we are doing the second or more
1078 	 * hammer2 mounts from the same device.
1079 	 */
1080 	lockmgr(&hammer2_mntlk, LK_EXCLUSIVE);
1081 	if (!TAILQ_EMPTY(&devvpl)) {
1082 		/*
1083 		 * Match the device.  Due to the way devfs works,
1084 		 * we may not be able to directly match the vnode pointer,
1085 		 * so also check to see if the underlying device matches.
1086 		 */
1087 		TAILQ_FOREACH(hmp_tmp, &hammer2_mntlist, mntentry) {
1088 			TAILQ_FOREACH(e_tmp, &hmp_tmp->devvpl, entry) {
1089 				int devvp_found = 0;
1090 				TAILQ_FOREACH(e, &devvpl, entry) {
1091 					KKASSERT(e->devvp);
1092 					if (e_tmp->devvp == e->devvp)
1093 						devvp_found = 1;
1094 					if (e_tmp->devvp->v_rdev &&
1095 					    e_tmp->devvp->v_rdev == e->devvp->v_rdev)
1096 						devvp_found = 1;
1097 				}
1098 				if (!devvp_found)
1099 					goto next_hmp;
1100 			}
1101 			hmp = hmp_tmp;
1102 			kprintf("hammer2_mount: hmp=%p matched\n", hmp);
1103 			break;
1104 next_hmp:
1105 			continue;
1106 		}
1107 
1108 		/*
1109 		 * If no match this may be a fresh H2 mount, make sure
1110 		 * the device is not mounted on anything else.
1111 		 */
1112 		if (hmp == NULL) {
1113 			TAILQ_FOREACH(e, &devvpl, entry) {
1114 				struct vnode *devvp = e->devvp;
1115 				KKASSERT(devvp);
1116 				error = vfs_mountedon(devvp);
1117 				if (error) {
1118 					kprintf("hammer2_mount: %s mounted %d\n",
1119 						e->path, error);
1120 					hammer2_cleanup_devvp(&devvpl);
1121 					lockmgr(&hammer2_mntlk, LK_RELEASE);
1122 					return error;
1123 				}
1124 			}
1125 		}
1126 	} else {
1127 		/*
1128 		 * Match the label to a pmp already probed.
1129 		 */
1130 		TAILQ_FOREACH(pmp, &hammer2_pfslist, mntentry) {
1131 			for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
1132 				if (pmp->pfs_names[i] &&
1133 				    strcmp(pmp->pfs_names[i], label) == 0) {
1134 					hmp = pmp->pfs_hmps[i];
1135 					break;
1136 				}
1137 			}
1138 			if (hmp)
1139 				break;
1140 		}
1141 		if (hmp == NULL) {
1142 			kprintf("hammer2_mount: PFS label \"%s\" not found\n",
1143 				label);
1144 			hammer2_cleanup_devvp(&devvpl);
1145 			lockmgr(&hammer2_mntlk, LK_RELEASE);
1146 			return ENOENT;
1147 		}
1148 	}
1149 
1150 	/*
1151 	 * Open the device if this isn't a secondary mount and construct
1152 	 * the H2 device mount (hmp).
1153 	 */
1154 	if (hmp == NULL) {
1155 		hammer2_chain_t *schain;
1156 		hammer2_xid_t xid;
1157 		hammer2_xop_head_t xop;
1158 
1159 		/*
1160 		 * Now open the device
1161 		 */
1162 		KKASSERT(!TAILQ_EMPTY(&devvpl));
1163 		if (error == 0) {
1164 			error = hammer2_open_devvp(&devvpl, ronly);
1165 			if (error) {
1166 				hammer2_close_devvp(&devvpl, ronly);
1167 				hammer2_cleanup_devvp(&devvpl);
1168 				lockmgr(&hammer2_mntlk, LK_RELEASE);
1169 				return error;
1170 			}
1171 		}
1172 
1173 		/*
1174 		 * Construct volumes and link with device vnodes.
1175 		 */
1176 		hmp = kmalloc(sizeof(*hmp), M_HAMMER2, M_WAITOK | M_ZERO);
1177 		hmp->devvp = NULL;
1178 		error = hammer2_init_volumes(mp, &devvpl, hmp->volumes,
1179 					     &hmp->voldata, &hmp->devvp);
1180 		if (error) {
1181 			hammer2_close_devvp(&devvpl, ronly);
1182 			hammer2_cleanup_devvp(&devvpl);
1183 			lockmgr(&hammer2_mntlk, LK_RELEASE);
1184 			kfree(hmp, M_HAMMER2);
1185 			return error;
1186 		}
1187 		if (!hmp->devvp) {
1188 			kprintf("hammer2: failed to initialize root volume\n");
1189 			hammer2_unmount_helper(mp, NULL, hmp);
1190 			lockmgr(&hammer2_mntlk, LK_RELEASE);
1191 			hammer2_vfs_unmount(mp, MNT_FORCE);
1192 			return EINVAL;
1193 		}
1194 
1195 		ksnprintf(hmp->devrepname, sizeof(hmp->devrepname), "%s", dev);
1196 		hmp->ronly = ronly;
1197 		hmp->hflags = info.hflags & HMNT2_DEVFLAGS;
1198 		kmalloc_create(&hmp->mchain, "HAMMER2-chains");
1199 		TAILQ_INSERT_TAIL(&hammer2_mntlist, hmp, mntentry);
1200 		RB_INIT(&hmp->iotree);
1201 		spin_init(&hmp->io_spin, "h2mount_io");
1202 		spin_init(&hmp->list_spin, "h2mount_list");
1203 
1204 		lockinit(&hmp->vollk, "h2vol", 0, 0);
1205 		lockinit(&hmp->bulklk, "h2bulk", 0, 0);
1206 		lockinit(&hmp->bflock, "h2bflk", 0, 0);
1207 
1208 		/*
1209 		 * vchain setup. vchain.data is embedded.
1210 		 * vchain.refs is initialized and will never drop to 0.
1211 		 *
1212 		 * NOTE! voldata is not yet loaded.
1213 		 */
1214 		hmp->vchain.hmp = hmp;
1215 		hmp->vchain.refs = 1;
1216 		hmp->vchain.data = (void *)&hmp->voldata;
1217 		hmp->vchain.bref.type = HAMMER2_BREF_TYPE_VOLUME;
1218 		hmp->vchain.bref.data_off = 0 | HAMMER2_PBUFRADIX;
1219 		hmp->vchain.bref.mirror_tid = hmp->voldata.mirror_tid;
1220 		hammer2_chain_core_init(&hmp->vchain);
1221 
1222 		/*
1223 		 * fchain setup.  fchain.data is embedded.
1224 		 * fchain.refs is initialized and will never drop to 0.
1225 		 *
1226 		 * The data is not used but needs to be initialized to
1227 		 * pass assertion muster.  We use this chain primarily
1228 		 * as a placeholder for the freemap's top-level radix tree
1229 		 * so it does not interfere with the volume's topology
1230 		 * radix tree.
1231 		 */
1232 		hmp->fchain.hmp = hmp;
1233 		hmp->fchain.refs = 1;
1234 		hmp->fchain.data = (void *)&hmp->voldata.freemap_blockset;
1235 		hmp->fchain.bref.type = HAMMER2_BREF_TYPE_FREEMAP;
1236 		hmp->fchain.bref.data_off = 0 | HAMMER2_PBUFRADIX;
1237 		hmp->fchain.bref.mirror_tid = hmp->voldata.freemap_tid;
1238 		hmp->fchain.bref.methods =
1239 			HAMMER2_ENC_CHECK(HAMMER2_CHECK_FREEMAP) |
1240 			HAMMER2_ENC_COMP(HAMMER2_COMP_NONE);
1241 		hammer2_chain_core_init(&hmp->fchain);
1242 
1243 		/*
1244 		 * Initialize volume header related fields.
1245 		 */
1246 		KKASSERT(hmp->voldata.magic == HAMMER2_VOLUME_ID_HBO ||
1247 			 hmp->voldata.magic == HAMMER2_VOLUME_ID_ABO);
1248 		hmp->volhdrno = error;
1249 		hmp->volsync = hmp->voldata;
1250 		hmp->free_reserved = hmp->voldata.allocator_size / 20;
1251 		/*
1252 		 * Must use hmp instead of volume header for these two
1253 		 * in order to handle volume versions transparently.
1254 		 */
1255 		if (hmp->voldata.version >= HAMMER2_VOL_VERSION_MULTI_VOLUMES) {
1256 			hmp->nvolumes = hmp->voldata.nvolumes;
1257 			hmp->total_size = hmp->voldata.total_size;
1258 		} else {
1259 			hmp->nvolumes = 1;
1260 			hmp->total_size = hmp->voldata.volu_size;
1261 		}
1262 		KKASSERT(hmp->nvolumes > 0);
1263 
1264 		/*
1265 		 * Move devvpl entries to hmp.
1266 		 */
1267 		TAILQ_INIT(&hmp->devvpl);
1268 		while ((e = TAILQ_FIRST(&devvpl)) != NULL) {
1269 			TAILQ_REMOVE(&devvpl, e, entry);
1270 			TAILQ_INSERT_TAIL(&hmp->devvpl, e, entry);
1271 		}
1272 		KKASSERT(TAILQ_EMPTY(&devvpl));
1273 		KKASSERT(!TAILQ_EMPTY(&hmp->devvpl));
1274 
1275 		/*
1276 		 * Really important to get these right or the flush and
1277 		 * teardown code will get confused.
1278 		 */
1279 		hmp->spmp = hammer2_pfsalloc(NULL, NULL, 0, NULL);
1280 		spmp = hmp->spmp;
1281 		spmp->pfs_hmps[0] = hmp;
1282 
1283 		/*
1284 		 * Dummy-up vchain and fchain's modify_tid.  mirror_tid
1285 		 * is inherited from the volume header.
1286 		 */
1287 		xid = 0;
1288 		hmp->vchain.bref.mirror_tid = hmp->voldata.mirror_tid;
1289 		hmp->vchain.bref.modify_tid = hmp->vchain.bref.mirror_tid;
1290 		hmp->vchain.pmp = spmp;
1291 		hmp->fchain.bref.mirror_tid = hmp->voldata.freemap_tid;
1292 		hmp->fchain.bref.modify_tid = hmp->fchain.bref.mirror_tid;
1293 		hmp->fchain.pmp = spmp;
1294 
1295 		/*
1296 		 * First locate the super-root inode, which is key 0
1297 		 * relative to the volume header's blockset.
1298 		 *
1299 		 * Then locate the root inode by scanning the directory keyspace
1300 		 * represented by the label.
1301 		 */
1302 		parent = hammer2_chain_lookup_init(&hmp->vchain, 0);
1303 		schain = hammer2_chain_lookup(&parent, &key_dummy,
1304 				      HAMMER2_SROOT_KEY, HAMMER2_SROOT_KEY,
1305 				      &error, 0);
1306 		hammer2_chain_lookup_done(parent);
1307 		if (schain == NULL) {
1308 			kprintf("hammer2_mount: invalid super-root\n");
1309 			hammer2_unmount_helper(mp, NULL, hmp);
1310 			lockmgr(&hammer2_mntlk, LK_RELEASE);
1311 			hammer2_vfs_unmount(mp, MNT_FORCE);
1312 			return EINVAL;
1313 		}
1314 		if (schain->error) {
1315 			kprintf("hammer2_mount: error %s reading super-root\n",
1316 				hammer2_error_str(schain->error));
1317 			hammer2_chain_unlock(schain);
1318 			hammer2_chain_drop(schain);
1319 			schain = NULL;
1320 			hammer2_unmount_helper(mp, NULL, hmp);
1321 			lockmgr(&hammer2_mntlk, LK_RELEASE);
1322 			hammer2_vfs_unmount(mp, MNT_FORCE);
1323 			return EINVAL;
1324 		}
1325 
1326 		/*
1327 		 * The super-root always uses an inode_tid of 1 when
1328 		 * creating PFSs.
1329 		 */
1330 		spmp->inode_tid = 1;
1331 		spmp->modify_tid = schain->bref.modify_tid + 1;
1332 
1333 		/*
1334 		 * Sanity-check schain's pmp and finish initialization.
1335 		 * Any chain belonging to the super-root topology should
1336 		 * have a NULL pmp (not even set to spmp).
1337 		 */
1338 		ripdata = &schain->data->ipdata;
1339 		KKASSERT(schain->pmp == NULL);
1340 		spmp->pfs_clid = ripdata->meta.pfs_clid;
1341 
1342 		/*
1343 		 * Replace the dummy spmp->iroot with a real one.  It's
1344 		 * easier to just do a wholesale replacement than to try
1345 		 * to update the chain and fixup the iroot fields.
1346 		 *
1347 		 * The returned inode is locked with the supplied cluster.
1348 		 */
1349 		hammer2_dummy_xop_from_chain(&xop, schain);
1350 		hammer2_inode_drop(spmp->iroot);
1351 		spmp->iroot = NULL;
1352 		spmp->iroot = hammer2_inode_get(spmp, &xop, -1, -1);
1353 		spmp->spmp_hmp = hmp;
1354 		spmp->pfs_types[0] = ripdata->meta.pfs_type;
1355 		spmp->pfs_hmps[0] = hmp;
1356 		hammer2_inode_ref(spmp->iroot);
1357 		hammer2_inode_unlock(spmp->iroot);
1358 		hammer2_cluster_unlock(&xop.cluster);
1359 		hammer2_chain_drop(schain);
1360 		/* do not call hammer2_cluster_drop() on an embedded cluster */
1361 		schain = NULL;	/* now invalid */
1362 		/* leave spmp->iroot with one ref */
1363 
1364 		if (!hmp->ronly) {
1365 			error = hammer2_recovery(hmp);
1366 			if (error == 0)
1367 				error |= hammer2_fixup_pfses(hmp);
1368 			/* XXX do something with error */
1369 		}
1370 		hammer2_update_pmps(hmp);
1371 		hammer2_iocom_init(hmp);
1372 		hammer2_bulkfree_init(hmp);
1373 
1374 		/*
1375 		 * Ref the cluster management messaging descriptor.  The mount
1376 		 * program deals with the other end of the communications pipe.
1377 		 *
1378 		 * Root mounts typically do not supply one.
1379 		 */
1380 		if (info.cluster_fd >= 0) {
1381 			fp = holdfp(curthread, info.cluster_fd, -1);
1382 			if (fp) {
1383 				hammer2_cluster_reconnect(hmp, fp);
1384 			} else {
1385 				kprintf("hammer2_mount: bad cluster_fd!\n");
1386 			}
1387 		}
1388 	} else {
1389 		spmp = hmp->spmp;
1390 		if (info.hflags & HMNT2_DEVFLAGS) {
1391 			kprintf("hammer2_mount: Warning: mount flags pertaining "
1392 				"to the whole device may only be specified "
1393 				"on the first mount of the device: %08x\n",
1394 				info.hflags & HMNT2_DEVFLAGS);
1395 		}
1396 	}
1397 
1398 	/*
1399 	 * Force local mount (disassociate all PFSs from their clusters).
1400 	 * Used primarily for debugging.
1401 	 */
1402 	force_local = (hmp->hflags & HMNT2_LOCAL) ? hmp : NULL;
1403 
1404 	/*
1405 	 * Lookup the mount point under the media-localized super-root.
1406 	 * Scanning hammer2_pfslist doesn't help us because it represents
1407 	 * PFS cluster ids which can aggregate several named PFSs together.
1408 	 *
1409 	 * cluster->pmp will incorrectly point to spmp and must be fixed
1410 	 * up later on.
1411 	 */
1412 	hammer2_inode_lock(spmp->iroot, 0);
1413 	parent = hammer2_inode_chain(spmp->iroot, 0, HAMMER2_RESOLVE_ALWAYS);
1414 	lhc = hammer2_dirhash(label, strlen(label));
1415 	chain = hammer2_chain_lookup(&parent, &key_next,
1416 				     lhc, lhc + HAMMER2_DIRHASH_LOMASK,
1417 				     &error, 0);
1418 	while (chain) {
1419 		if (chain->bref.type == HAMMER2_BREF_TYPE_INODE &&
1420 		    strcmp(label, chain->data->ipdata.filename) == 0) {
1421 			break;
1422 		}
1423 		chain = hammer2_chain_next(&parent, chain, &key_next,
1424 					    key_next,
1425 					    lhc + HAMMER2_DIRHASH_LOMASK,
1426 					    &error, 0);
1427 	}
1428 	if (parent) {
1429 		hammer2_chain_unlock(parent);
1430 		hammer2_chain_drop(parent);
1431 	}
1432 	hammer2_inode_unlock(spmp->iroot);
1433 
1434 	/*
1435 	 * PFS could not be found?
1436 	 */
1437 	if (chain == NULL) {
1438 		hammer2_unmount_helper(mp, NULL, hmp);
1439 		lockmgr(&hammer2_mntlk, LK_RELEASE);
1440 		hammer2_vfs_unmount(mp, MNT_FORCE);
1441 
1442 		if (error) {
1443 			kprintf("hammer2_mount: PFS label I/O error\n");
1444 			return EINVAL;
1445 		} else {
1446 			kprintf("hammer2_mount: PFS label \"%s\" not found\n",
1447 				label);
1448 			return ENOENT;
1449 		}
1450 	}
1451 
1452 	/*
1453 	 * Acquire the pmp structure (it should have already been allocated
1454 	 * via hammer2_update_pmps() so do not pass cluster in to add to
1455 	 * available chains).
1456 	 *
1457 	 * Check if the cluster has already been mounted.  A cluster can
1458 	 * only be mounted once, use null mounts to mount additional copies.
1459 	 */
1460 	if (chain->error) {
1461 		kprintf("hammer2_mount: PFS label I/O error\n");
1462 	} else {
1463 		ripdata = &chain->data->ipdata;
1464 		bref = chain->bref;
1465 		pmp = hammer2_pfsalloc(NULL, ripdata,
1466 				       bref.modify_tid, force_local);
1467 	}
1468 	hammer2_chain_unlock(chain);
1469 	hammer2_chain_drop(chain);
1470 
1471 	/*
1472 	 * Finish the mount
1473 	 */
1474         kprintf("hammer2_mount: hmp=%p pmp=%p\n", hmp, pmp);
1475 
1476 	if (pmp->mp) {
1477 		kprintf("hammer2_mount: PFS already mounted!\n");
1478 		hammer2_unmount_helper(mp, NULL, hmp);
1479 		lockmgr(&hammer2_mntlk, LK_RELEASE);
1480 		hammer2_vfs_unmount(mp, MNT_FORCE);
1481 
1482 		return EBUSY;
1483 	}
1484 
1485 	pmp->hflags = info.hflags;
1486         mp->mnt_flag |= MNT_LOCAL;
1487         mp->mnt_kern_flag |= MNTK_ALL_MPSAFE;   /* all entry pts are SMP */
1488         mp->mnt_kern_flag |= MNTK_THR_SYNC;     /* new vsyncscan semantics */
1489 
1490         /*
1491          * required mount structure initializations
1492          */
1493         mp->mnt_stat.f_iosize = HAMMER2_PBUFSIZE;
1494         mp->mnt_stat.f_bsize = HAMMER2_PBUFSIZE;
1495 
1496         mp->mnt_vstat.f_frsize = HAMMER2_PBUFSIZE;
1497         mp->mnt_vstat.f_bsize = HAMMER2_PBUFSIZE;
1498 
1499         /*
1500          * Optional fields
1501          */
1502         mp->mnt_iosize_max = MAXPHYS;
1503 
1504 	/*
1505 	 * Connect up mount pointers.
1506 	 */
1507 	hammer2_mount_helper(mp, pmp);
1508         lockmgr(&hammer2_mntlk, LK_RELEASE);
1509 
1510 	/*
1511 	 * Finish setup
1512 	 */
1513 	vfs_getnewfsid(mp);
1514 	vfs_add_vnodeops(mp, &hammer2_vnode_vops, &mp->mnt_vn_norm_ops);
1515 	vfs_add_vnodeops(mp, &hammer2_spec_vops, &mp->mnt_vn_spec_ops);
1516 	vfs_add_vnodeops(mp, &hammer2_fifo_vops, &mp->mnt_vn_fifo_ops);
1517 
1518 	if (path) {
1519 		copyinstr(info.volume, mp->mnt_stat.f_mntfromname,
1520 			  MNAMELEN - 1, &size);
1521 		bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
1522 	} /* else root mount, already in there */
1523 
1524 	bzero(mp->mnt_stat.f_mntonname, sizeof(mp->mnt_stat.f_mntonname));
1525 	if (path) {
1526 		copyinstr(path, mp->mnt_stat.f_mntonname,
1527 			  sizeof(mp->mnt_stat.f_mntonname) - 1,
1528 			  &size);
1529 	} else {
1530 		/* root mount */
1531 		mp->mnt_stat.f_mntonname[0] = '/';
1532 	}
1533 
1534 	/*
1535 	 * Initial statfs to prime mnt_stat.
1536 	 */
1537 	hammer2_vfs_statfs(mp, &mp->mnt_stat, cred);
1538 
1539 	return 0;
1540 }
1541 
1542 /*
1543  * Scan PFSs under the super-root and create hammer2_pfs structures.
1544  */
1545 static
1546 void
1547 hammer2_update_pmps(hammer2_dev_t *hmp)
1548 {
1549 	const hammer2_inode_data_t *ripdata;
1550 	hammer2_chain_t *parent;
1551 	hammer2_chain_t *chain;
1552 	hammer2_blockref_t bref;
1553 	hammer2_dev_t *force_local;
1554 	hammer2_pfs_t *spmp;
1555 	hammer2_pfs_t *pmp;
1556 	hammer2_key_t key_next;
1557 	int error;
1558 
1559 	/*
1560 	 * Force local mount (disassociate all PFSs from their clusters).
1561 	 * Used primarily for debugging.
1562 	 */
1563 	force_local = (hmp->hflags & HMNT2_LOCAL) ? hmp : NULL;
1564 
1565 	/*
1566 	 * Lookup mount point under the media-localized super-root.
1567 	 *
1568 	 * cluster->pmp will incorrectly point to spmp and must be fixed
1569 	 * up later on.
1570 	 */
1571 	spmp = hmp->spmp;
1572 	hammer2_inode_lock(spmp->iroot, 0);
1573 	parent = hammer2_inode_chain(spmp->iroot, 0, HAMMER2_RESOLVE_ALWAYS);
1574 	chain = hammer2_chain_lookup(&parent, &key_next,
1575 					 HAMMER2_KEY_MIN, HAMMER2_KEY_MAX,
1576 					 &error, 0);
1577 	while (chain) {
1578 		if (chain->error) {
1579 			kprintf("I/O error scanning PFS labels\n");
1580 		} else if (chain->bref.type != HAMMER2_BREF_TYPE_INODE) {
1581 			kprintf("Non inode chain type %d under super-root\n",
1582 				chain->bref.type);
1583 		} else {
1584 			ripdata = &chain->data->ipdata;
1585 			bref = chain->bref;
1586 			pmp = hammer2_pfsalloc(chain, ripdata,
1587 					       bref.modify_tid, force_local);
1588 		}
1589 		chain = hammer2_chain_next(&parent, chain, &key_next,
1590 					   key_next, HAMMER2_KEY_MAX,
1591 					   &error, 0);
1592 	}
1593 	if (parent) {
1594 		hammer2_chain_unlock(parent);
1595 		hammer2_chain_drop(parent);
1596 	}
1597 	hammer2_inode_unlock(spmp->iroot);
1598 }
1599 
1600 static
1601 int
1602 hammer2_remount(hammer2_dev_t *hmp, struct mount *mp, char *path __unused,
1603 		struct ucred *cred)
1604 {
1605 	hammer2_volume_t *vol;
1606 	struct vnode *devvp;
1607 	int i, error, result = 0;
1608 
1609 	if (!(hmp->ronly && (mp->mnt_kern_flag & MNTK_WANTRDWR)))
1610 		return 0;
1611 
1612 	for (i = 0; i < hmp->nvolumes; ++i) {
1613 		vol = &hmp->volumes[i];
1614 		devvp = vol->dev->devvp;
1615 		KKASSERT(devvp);
1616 		vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
1617 		VOP_OPEN(devvp, FREAD | FWRITE, FSCRED, NULL);
1618 		vn_unlock(devvp);
1619 		error = 0;
1620 		if (vol->id == HAMMER2_ROOT_VOLUME) {
1621 			error = hammer2_recovery(hmp);
1622 			if (error == 0)
1623 				error |= hammer2_fixup_pfses(hmp);
1624 		}
1625 		vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
1626 		if (error == 0) {
1627 			VOP_CLOSE(devvp, FREAD, NULL);
1628 		} else {
1629 			VOP_CLOSE(devvp, FREAD | FWRITE, NULL);
1630 		}
1631 		vn_unlock(devvp);
1632 		result |= error;
1633 	}
1634 	if (result == 0) {
1635 		kprintf("hammer2: enable read/write\n");
1636 		hmp->ronly = 0;
1637 	}
1638 
1639 	return result;
1640 }
1641 
1642 static
1643 int
1644 hammer2_vfs_unmount(struct mount *mp, int mntflags)
1645 {
1646 	hammer2_pfs_t *pmp;
1647 	int flags;
1648 	int error = 0;
1649 
1650 	pmp = MPTOPMP(mp);
1651 
1652 	if (pmp == NULL)
1653 		return(0);
1654 
1655 	lockmgr(&hammer2_mntlk, LK_EXCLUSIVE);
1656 
1657 	/*
1658 	 * If mount initialization proceeded far enough we must flush
1659 	 * its vnodes and sync the underlying mount points.  Three syncs
1660 	 * are required to fully flush the filesystem (freemap updates lag
1661 	 * by one flush, and one extra for safety).
1662 	 */
1663 	if (mntflags & MNT_FORCE)
1664 		flags = FORCECLOSE;
1665 	else
1666 		flags = 0;
1667 	if (pmp->iroot) {
1668 		error = vflush(mp, 0, flags);
1669 		if (error)
1670 			goto failed;
1671 		hammer2_vfs_sync(mp, MNT_WAIT);
1672 		hammer2_vfs_sync(mp, MNT_WAIT);
1673 		hammer2_vfs_sync(mp, MNT_WAIT);
1674 	}
1675 
1676 	/*
1677 	 * Cleanup the frontend support XOPS threads
1678 	 */
1679 	hammer2_xop_helper_cleanup(pmp);
1680 
1681 	if (pmp->mp)
1682 		hammer2_unmount_helper(mp, pmp, NULL);
1683 
1684 	error = 0;
1685 failed:
1686 	lockmgr(&hammer2_mntlk, LK_RELEASE);
1687 
1688 	return (error);
1689 }
1690 
1691 /*
1692  * Mount helper, hook the system mount into our PFS.
1693  * The mount lock is held.
1694  *
1695  * We must bump the mount_count on related devices for any
1696  * mounted PFSs.
1697  */
1698 static
1699 void
1700 hammer2_mount_helper(struct mount *mp, hammer2_pfs_t *pmp)
1701 {
1702 	hammer2_cluster_t *cluster;
1703 	hammer2_chain_t *rchain;
1704 	int i;
1705 
1706         mp->mnt_data = (qaddr_t)pmp;
1707 	pmp->mp = mp;
1708 
1709 	/*
1710 	 * After pmp->mp is set we have to adjust hmp->mount_count.
1711 	 */
1712 	cluster = &pmp->iroot->cluster;
1713 	for (i = 0; i < cluster->nchains; ++i) {
1714 		rchain = cluster->array[i].chain;
1715 		if (rchain == NULL)
1716 			continue;
1717 		++rchain->hmp->mount_count;
1718 	}
1719 
1720 	/*
1721 	 * Create missing Xop threads
1722 	 */
1723 	hammer2_xop_helper_create(pmp);
1724 }
1725 
1726 /*
1727  * Mount helper, unhook the system mount from our PFS.
1728  * The mount lock is held.
1729  *
1730  * If hmp is supplied a mount responsible for being the first to open
1731  * the block device failed and the block device and all PFSs using the
1732  * block device must be cleaned up.
1733  *
1734  * If pmp is supplied multiple devices might be backing the PFS and each
1735  * must be disconnected.  This might not be the last PFS using some of the
1736  * underlying devices.  Also, we have to adjust our hmp->mount_count
1737  * accounting for the devices backing the pmp which is now undergoing an
1738  * unmount.
1739  */
1740 static
1741 void
1742 hammer2_unmount_helper(struct mount *mp, hammer2_pfs_t *pmp, hammer2_dev_t *hmp)
1743 {
1744 	hammer2_cluster_t *cluster;
1745 	hammer2_chain_t *rchain;
1746 	int dumpcnt;
1747 	int i;
1748 
1749 	/*
1750 	 * If no device supplied this is a high-level unmount and we have to
1751 	 * to disconnect the mount, adjust mount_count, and locate devices
1752 	 * that might now have no mounts.
1753 	 */
1754 	if (pmp) {
1755 		KKASSERT(hmp == NULL);
1756 		KKASSERT((void *)(intptr_t)mp->mnt_data == pmp);
1757 		pmp->mp = NULL;
1758 		mp->mnt_data = NULL;
1759 
1760 		/*
1761 		 * After pmp->mp is cleared we have to account for
1762 		 * mount_count.
1763 		 */
1764 		cluster = &pmp->iroot->cluster;
1765 		for (i = 0; i < cluster->nchains; ++i) {
1766 			rchain = cluster->array[i].chain;
1767 			if (rchain == NULL)
1768 				continue;
1769 			--rchain->hmp->mount_count;
1770 			/* scrapping hmp now may invalidate the pmp */
1771 		}
1772 again:
1773 		TAILQ_FOREACH(hmp, &hammer2_mntlist, mntentry) {
1774 			if (hmp->mount_count == 0) {
1775 				hammer2_unmount_helper(NULL, NULL, hmp);
1776 				goto again;
1777 			}
1778 		}
1779 		return;
1780 	}
1781 
1782 	/*
1783 	 * Try to terminate the block device.  We can't terminate it if
1784 	 * there are still PFSs referencing it.
1785 	 */
1786 	if (hmp->mount_count)
1787 		return;
1788 
1789 	/*
1790 	 * Decomission the network before we start messing with the
1791 	 * device and PFS.
1792 	 */
1793 	hammer2_iocom_uninit(hmp);
1794 
1795 	hammer2_bulkfree_uninit(hmp);
1796 	hammer2_pfsfree_scan(hmp, 0);
1797 
1798 	/*
1799 	 * Cycle the volume data lock as a safety (probably not needed any
1800 	 * more).  To ensure everything is out we need to flush at least
1801 	 * three times.  (1) The running of the sideq can dirty the
1802 	 * filesystem, (2) A normal flush can dirty the freemap, and
1803 	 * (3) ensure that the freemap is fully synchronized.
1804 	 *
1805 	 * The next mount's recovery scan can clean everything up but we want
1806 	 * to leave the filesystem in a 100% clean state on a normal unmount.
1807 	 */
1808 #if 0
1809 	hammer2_voldata_lock(hmp);
1810 	hammer2_voldata_unlock(hmp);
1811 #endif
1812 
1813 	/*
1814 	 * Flush whatever is left.  Unmounted but modified PFS's might still
1815 	 * have some dirty chains on them.
1816 	 */
1817 	hammer2_chain_lock(&hmp->vchain, HAMMER2_RESOLVE_ALWAYS);
1818 	hammer2_chain_lock(&hmp->fchain, HAMMER2_RESOLVE_ALWAYS);
1819 
1820 	if (hmp->fchain.flags & HAMMER2_CHAIN_FLUSH_MASK) {
1821 		hammer2_voldata_modify(hmp);
1822 		hammer2_flush(&hmp->fchain, HAMMER2_FLUSH_TOP |
1823 					    HAMMER2_FLUSH_ALL);
1824 	}
1825 	hammer2_chain_unlock(&hmp->fchain);
1826 
1827 	if (hmp->vchain.flags & HAMMER2_CHAIN_FLUSH_MASK) {
1828 		hammer2_flush(&hmp->vchain, HAMMER2_FLUSH_TOP |
1829 					    HAMMER2_FLUSH_ALL);
1830 	}
1831 	hammer2_chain_unlock(&hmp->vchain);
1832 
1833 	if ((hmp->vchain.flags | hmp->fchain.flags) &
1834 	    HAMMER2_CHAIN_FLUSH_MASK) {
1835 		kprintf("hammer2_unmount: chains left over after final sync\n");
1836 		kprintf("    vchain %08x\n", hmp->vchain.flags);
1837 		kprintf("    fchain %08x\n", hmp->fchain.flags);
1838 
1839 		if (hammer2_debug & 0x0010)
1840 			Debugger("entered debugger");
1841 	}
1842 
1843 	hammer2_pfsfree_scan(hmp, 1);
1844 
1845 	KKASSERT(hmp->spmp == NULL);
1846 
1847 	/*
1848 	 * Finish up with the device vnode
1849 	 */
1850 	if (!TAILQ_EMPTY(&hmp->devvpl)) {
1851 		hammer2_close_devvp(&hmp->devvpl, hmp->ronly);
1852 		hammer2_cleanup_devvp(&hmp->devvpl);
1853 	}
1854 	KKASSERT(TAILQ_EMPTY(&hmp->devvpl));
1855 
1856 	/*
1857 	 * Clear vchain/fchain flags that might prevent final cleanup
1858 	 * of these chains.
1859 	 */
1860 	if (hmp->vchain.flags & HAMMER2_CHAIN_MODIFIED) {
1861 		atomic_add_long(&hammer2_count_modified_chains, -1);
1862 		atomic_clear_int(&hmp->vchain.flags, HAMMER2_CHAIN_MODIFIED);
1863 		hammer2_pfs_memory_wakeup(hmp->vchain.pmp, -1);
1864 	}
1865 	if (hmp->vchain.flags & HAMMER2_CHAIN_UPDATE) {
1866 		atomic_clear_int(&hmp->vchain.flags, HAMMER2_CHAIN_UPDATE);
1867 	}
1868 
1869 	if (hmp->fchain.flags & HAMMER2_CHAIN_MODIFIED) {
1870 		atomic_add_long(&hammer2_count_modified_chains, -1);
1871 		atomic_clear_int(&hmp->fchain.flags, HAMMER2_CHAIN_MODIFIED);
1872 		hammer2_pfs_memory_wakeup(hmp->fchain.pmp, -1);
1873 	}
1874 	if (hmp->fchain.flags & HAMMER2_CHAIN_UPDATE) {
1875 		atomic_clear_int(&hmp->fchain.flags, HAMMER2_CHAIN_UPDATE);
1876 	}
1877 
1878 	/*
1879 	 * Final drop of embedded freemap root chain to
1880 	 * clean up fchain.core (fchain structure is not
1881 	 * flagged ALLOCATED so it is cleaned out and then
1882 	 * left to rot).
1883 	 */
1884 	hammer2_chain_drop(&hmp->fchain);
1885 
1886 	/*
1887 	 * Final drop of embedded volume root chain to clean
1888 	 * up vchain.core (vchain structure is not flagged
1889 	 * ALLOCATED so it is cleaned out and then left to
1890 	 * rot).
1891 	 */
1892 	dumpcnt = 50;
1893 	hammer2_dump_chain(&hmp->vchain, 0, 0, &dumpcnt, 'v', (u_int)-1);
1894 	dumpcnt = 50;
1895 	hammer2_dump_chain(&hmp->fchain, 0, 0, &dumpcnt, 'f', (u_int)-1);
1896 
1897 	hammer2_chain_drop(&hmp->vchain);
1898 
1899 	hammer2_io_cleanup(hmp, &hmp->iotree);
1900 	if (hmp->iofree_count) {
1901 		kprintf("io_cleanup: %d I/O's left hanging\n",
1902 			hmp->iofree_count);
1903 	}
1904 
1905 	TAILQ_REMOVE(&hammer2_mntlist, hmp, mntentry);
1906 	kmalloc_destroy(&hmp->mchain);
1907 	kfree(hmp, M_HAMMER2);
1908 }
1909 
1910 int
1911 hammer2_vfs_vget(struct mount *mp, struct vnode *dvp,
1912 		 ino_t ino, struct vnode **vpp)
1913 {
1914 	hammer2_xop_lookup_t *xop;
1915 	hammer2_pfs_t *pmp;
1916 	hammer2_inode_t *ip;
1917 	hammer2_tid_t inum;
1918 	int error;
1919 
1920 	inum = (hammer2_tid_t)ino & HAMMER2_DIRHASH_USERMSK;
1921 
1922 	error = 0;
1923 	pmp = MPTOPMP(mp);
1924 
1925 	/*
1926 	 * Easy if we already have it cached
1927 	 */
1928 	ip = hammer2_inode_lookup(pmp, inum);
1929 	if (ip) {
1930 		hammer2_inode_lock(ip, HAMMER2_RESOLVE_SHARED);
1931 		*vpp = hammer2_igetv(ip, &error);
1932 		hammer2_inode_unlock(ip);
1933 		hammer2_inode_drop(ip);		/* from lookup */
1934 
1935 		return error;
1936 	}
1937 
1938 	/*
1939 	 * Otherwise we have to find the inode
1940 	 */
1941 	xop = hammer2_xop_alloc(pmp->iroot, 0);
1942 	xop->lhc = inum;
1943 	hammer2_xop_start(&xop->head, &hammer2_lookup_desc);
1944 	error = hammer2_xop_collect(&xop->head, 0);
1945 
1946 	if (error == 0)
1947 		ip = hammer2_inode_get(pmp, &xop->head, -1, -1);
1948 	hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP);
1949 
1950 	if (ip) {
1951 		*vpp = hammer2_igetv(ip, &error);
1952 		hammer2_inode_unlock(ip);
1953 	} else {
1954 		*vpp = NULL;
1955 		error = ENOENT;
1956 	}
1957 	return (error);
1958 }
1959 
1960 static
1961 int
1962 hammer2_vfs_root(struct mount *mp, struct vnode **vpp)
1963 {
1964 	hammer2_pfs_t *pmp;
1965 	struct vnode *vp;
1966 	int error;
1967 
1968 	pmp = MPTOPMP(mp);
1969 	if (pmp->iroot == NULL) {
1970 		kprintf("hammer2 (%s): no root inode\n",
1971 			mp->mnt_stat.f_mntfromname);
1972 		*vpp = NULL;
1973 		return EINVAL;
1974 	}
1975 
1976 	error = 0;
1977 	hammer2_inode_lock(pmp->iroot, HAMMER2_RESOLVE_SHARED);
1978 
1979 	while (pmp->inode_tid == 0) {
1980 		hammer2_xop_ipcluster_t *xop;
1981 		const hammer2_inode_meta_t *meta;
1982 
1983 		xop = hammer2_xop_alloc(pmp->iroot, HAMMER2_XOP_MODIFYING);
1984 		hammer2_xop_start(&xop->head, &hammer2_ipcluster_desc);
1985 		error = hammer2_xop_collect(&xop->head, 0);
1986 
1987 		if (error == 0) {
1988 			meta = &hammer2_xop_gdata(&xop->head)->ipdata.meta;
1989 			pmp->iroot->meta = *meta;
1990 			pmp->inode_tid = meta->pfs_inum + 1;
1991 			hammer2_xop_pdata(&xop->head);
1992 			/* meta invalid */
1993 
1994 			if (pmp->inode_tid < HAMMER2_INODE_START)
1995 				pmp->inode_tid = HAMMER2_INODE_START;
1996 			pmp->modify_tid =
1997 				xop->head.cluster.focus->bref.modify_tid + 1;
1998 #if 0
1999 			kprintf("PFS: Starting inode %jd\n",
2000 				(intmax_t)pmp->inode_tid);
2001 			kprintf("PMP focus good set nextino=%ld mod=%016jx\n",
2002 				pmp->inode_tid, pmp->modify_tid);
2003 #endif
2004 			wakeup(&pmp->iroot);
2005 
2006 			hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP);
2007 
2008 			/*
2009 			 * Prime the mount info.
2010 			 */
2011 			hammer2_vfs_statfs(mp, &mp->mnt_stat, NULL);
2012 			break;
2013 		}
2014 
2015 		/*
2016 		 * Loop, try again
2017 		 */
2018 		hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP);
2019 		hammer2_inode_unlock(pmp->iroot);
2020 		error = tsleep(&pmp->iroot, PCATCH, "h2root", hz);
2021 		hammer2_inode_lock(pmp->iroot, HAMMER2_RESOLVE_SHARED);
2022 		if (error == EINTR)
2023 			break;
2024 	}
2025 
2026 	if (error) {
2027 		hammer2_inode_unlock(pmp->iroot);
2028 		*vpp = NULL;
2029 	} else {
2030 		vp = hammer2_igetv(pmp->iroot, &error);
2031 		hammer2_inode_unlock(pmp->iroot);
2032 		*vpp = vp;
2033 	}
2034 
2035 	return (error);
2036 }
2037 
2038 /*
2039  * Filesystem status
2040  *
2041  * XXX incorporate ipdata->meta.inode_quota and data_quota
2042  */
2043 static
2044 int
2045 hammer2_vfs_statfs(struct mount *mp, struct statfs *sbp, struct ucred *cred)
2046 {
2047 	hammer2_pfs_t *pmp;
2048 	hammer2_dev_t *hmp;
2049 	hammer2_blockref_t bref;
2050 	struct statfs tmp;
2051 	int i;
2052 
2053 	/*
2054 	 * NOTE: iroot might not have validated the cluster yet.
2055 	 */
2056 	pmp = MPTOPMP(mp);
2057 
2058 	bzero(&tmp, sizeof(tmp));
2059 
2060 	for (i = 0; i < pmp->iroot->cluster.nchains; ++i) {
2061 		hmp = pmp->pfs_hmps[i];
2062 		if (hmp == NULL)
2063 			continue;
2064 		if (pmp->iroot->cluster.array[i].chain)
2065 			bref = pmp->iroot->cluster.array[i].chain->bref;
2066 		else
2067 			bzero(&bref, sizeof(bref));
2068 
2069 		tmp.f_files = bref.embed.stats.inode_count;
2070 		tmp.f_ffree = 0;
2071 		tmp.f_blocks = hmp->voldata.allocator_size /
2072 			       mp->mnt_vstat.f_bsize;
2073 		tmp.f_bfree = hmp->voldata.allocator_free /
2074 			      mp->mnt_vstat.f_bsize;
2075 		tmp.f_bavail = tmp.f_bfree;
2076 
2077 		if (cred && cred->cr_uid != 0) {
2078 			uint64_t adj;
2079 
2080 			/* 5% */
2081 			adj = hmp->free_reserved / mp->mnt_vstat.f_bsize;
2082 			tmp.f_blocks -= adj;
2083 			tmp.f_bfree -= adj;
2084 			tmp.f_bavail -= adj;
2085 		}
2086 
2087 		mp->mnt_stat.f_blocks = tmp.f_blocks;
2088 		mp->mnt_stat.f_bfree = tmp.f_bfree;
2089 		mp->mnt_stat.f_bavail = tmp.f_bavail;
2090 		mp->mnt_stat.f_files = tmp.f_files;
2091 		mp->mnt_stat.f_ffree = tmp.f_ffree;
2092 
2093 		*sbp = mp->mnt_stat;
2094 	}
2095 	return (0);
2096 }
2097 
2098 static
2099 int
2100 hammer2_vfs_statvfs(struct mount *mp, struct statvfs *sbp, struct ucred *cred)
2101 {
2102 	hammer2_pfs_t *pmp;
2103 	hammer2_dev_t *hmp;
2104 	hammer2_blockref_t bref;
2105 	struct statvfs tmp;
2106 	int i;
2107 
2108 	/*
2109 	 * NOTE: iroot might not have validated the cluster yet.
2110 	 */
2111 	pmp = MPTOPMP(mp);
2112 	bzero(&tmp, sizeof(tmp));
2113 
2114 	for (i = 0; i < pmp->iroot->cluster.nchains; ++i) {
2115 		hmp = pmp->pfs_hmps[i];
2116 		if (hmp == NULL)
2117 			continue;
2118 		if (pmp->iroot->cluster.array[i].chain)
2119 			bref = pmp->iroot->cluster.array[i].chain->bref;
2120 		else
2121 			bzero(&bref, sizeof(bref));
2122 
2123 		tmp.f_files = bref.embed.stats.inode_count;
2124 		tmp.f_ffree = 0;
2125 		tmp.f_blocks = hmp->voldata.allocator_size /
2126 			       mp->mnt_vstat.f_bsize;
2127 		tmp.f_bfree = hmp->voldata.allocator_free /
2128 			      mp->mnt_vstat.f_bsize;
2129 		tmp.f_bavail = tmp.f_bfree;
2130 
2131 		if (cred && cred->cr_uid != 0) {
2132 			uint64_t adj;
2133 
2134 			/* 5% */
2135 			adj = hmp->free_reserved / mp->mnt_vstat.f_bsize;
2136 			tmp.f_blocks -= adj;
2137 			tmp.f_bfree -= adj;
2138 			tmp.f_bavail -= adj;
2139 		}
2140 
2141 		mp->mnt_vstat.f_blocks = tmp.f_blocks;
2142 		mp->mnt_vstat.f_bfree = tmp.f_bfree;
2143 		mp->mnt_vstat.f_bavail = tmp.f_bavail;
2144 		mp->mnt_vstat.f_files = tmp.f_files;
2145 		mp->mnt_vstat.f_ffree = tmp.f_ffree;
2146 
2147 		*sbp = mp->mnt_vstat;
2148 	}
2149 	return (0);
2150 }
2151 
2152 /*
2153  * Mount-time recovery (RW mounts)
2154  *
2155  * Updates to the free block table are allowed to lag flushes by one
2156  * transaction.  In case of a crash, then on a fresh mount we must do an
2157  * incremental scan of the last committed transaction id and make sure that
2158  * all related blocks have been marked allocated.
2159  */
2160 struct hammer2_recovery_elm {
2161 	TAILQ_ENTRY(hammer2_recovery_elm) entry;
2162 	hammer2_chain_t *chain;
2163 	hammer2_tid_t sync_tid;
2164 };
2165 
2166 TAILQ_HEAD(hammer2_recovery_list, hammer2_recovery_elm);
2167 
2168 struct hammer2_recovery_info {
2169 	struct hammer2_recovery_list list;
2170 	hammer2_tid_t	mtid;
2171 	int	depth;
2172 };
2173 
2174 static int hammer2_recovery_scan(hammer2_dev_t *hmp,
2175 			hammer2_chain_t *parent,
2176 			struct hammer2_recovery_info *info,
2177 			hammer2_tid_t sync_tid);
2178 
2179 #define HAMMER2_RECOVERY_MAXDEPTH	10
2180 
2181 static
2182 int
2183 hammer2_recovery(hammer2_dev_t *hmp)
2184 {
2185 	struct hammer2_recovery_info info;
2186 	struct hammer2_recovery_elm *elm;
2187 	hammer2_chain_t *parent;
2188 	hammer2_tid_t sync_tid;
2189 	hammer2_tid_t mirror_tid;
2190 	int error;
2191 
2192 	hammer2_trans_init(hmp->spmp, 0);
2193 
2194 	sync_tid = hmp->voldata.freemap_tid;
2195 	mirror_tid = hmp->voldata.mirror_tid;
2196 
2197 	kprintf("hammer2_mount: \"%s\": ", hmp->devrepname);
2198 	if (sync_tid >= mirror_tid) {
2199 		kprintf("no recovery needed\n");
2200 	} else {
2201 		kprintf("freemap recovery %016jx-%016jx\n",
2202 			sync_tid + 1, mirror_tid);
2203 	}
2204 
2205 	TAILQ_INIT(&info.list);
2206 	info.depth = 0;
2207 	parent = hammer2_chain_lookup_init(&hmp->vchain, 0);
2208 	error = hammer2_recovery_scan(hmp, parent, &info, sync_tid);
2209 	hammer2_chain_lookup_done(parent);
2210 
2211 	while ((elm = TAILQ_FIRST(&info.list)) != NULL) {
2212 		TAILQ_REMOVE(&info.list, elm, entry);
2213 		parent = elm->chain;
2214 		sync_tid = elm->sync_tid;
2215 		kfree(elm, M_HAMMER2);
2216 
2217 		hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
2218 		error |= hammer2_recovery_scan(hmp, parent, &info,
2219 					      hmp->voldata.freemap_tid);
2220 		hammer2_chain_unlock(parent);
2221 		hammer2_chain_drop(parent);	/* drop elm->chain ref */
2222 	}
2223 
2224 	hammer2_trans_done(hmp->spmp, 0);
2225 
2226 	return error;
2227 }
2228 
2229 static
2230 int
2231 hammer2_recovery_scan(hammer2_dev_t *hmp, hammer2_chain_t *parent,
2232 		      struct hammer2_recovery_info *info,
2233 		      hammer2_tid_t sync_tid)
2234 {
2235 	const hammer2_inode_data_t *ripdata;
2236 	hammer2_chain_t *chain;
2237 	hammer2_blockref_t bref;
2238 	int tmp_error;
2239 	int rup_error;
2240 	int error;
2241 	int first;
2242 
2243 	/*
2244 	 * Adjust freemap to ensure that the block(s) are marked allocated.
2245 	 */
2246 	if (parent->bref.type != HAMMER2_BREF_TYPE_VOLUME) {
2247 		hammer2_freemap_adjust(hmp, &parent->bref,
2248 				       HAMMER2_FREEMAP_DORECOVER);
2249 	}
2250 
2251 	/*
2252 	 * Check type for recursive scan
2253 	 */
2254 	switch(parent->bref.type) {
2255 	case HAMMER2_BREF_TYPE_VOLUME:
2256 		/* data already instantiated */
2257 		break;
2258 	case HAMMER2_BREF_TYPE_INODE:
2259 		/*
2260 		 * Must instantiate data for DIRECTDATA test and also
2261 		 * for recursion.
2262 		 */
2263 		hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
2264 		ripdata = &parent->data->ipdata;
2265 		if (ripdata->meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA) {
2266 			/* not applicable to recovery scan */
2267 			hammer2_chain_unlock(parent);
2268 			return 0;
2269 		}
2270 		hammer2_chain_unlock(parent);
2271 		break;
2272 	case HAMMER2_BREF_TYPE_INDIRECT:
2273 		/*
2274 		 * Must instantiate data for recursion
2275 		 */
2276 		hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
2277 		hammer2_chain_unlock(parent);
2278 		break;
2279 	case HAMMER2_BREF_TYPE_DIRENT:
2280 	case HAMMER2_BREF_TYPE_DATA:
2281 	case HAMMER2_BREF_TYPE_FREEMAP:
2282 	case HAMMER2_BREF_TYPE_FREEMAP_NODE:
2283 	case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
2284 		/* not applicable to recovery scan */
2285 		return 0;
2286 		break;
2287 	default:
2288 		return HAMMER2_ERROR_BADBREF;
2289 	}
2290 
2291 	/*
2292 	 * Defer operation if depth limit reached.
2293 	 */
2294 	if (info->depth >= HAMMER2_RECOVERY_MAXDEPTH) {
2295 		struct hammer2_recovery_elm *elm;
2296 
2297 		elm = kmalloc(sizeof(*elm), M_HAMMER2, M_ZERO | M_WAITOK);
2298 		elm->chain = parent;
2299 		elm->sync_tid = sync_tid;
2300 		hammer2_chain_ref(parent);
2301 		TAILQ_INSERT_TAIL(&info->list, elm, entry);
2302 		/* unlocked by caller */
2303 
2304 		return(0);
2305 	}
2306 
2307 
2308 	/*
2309 	 * Recursive scan of the last flushed transaction only.  We are
2310 	 * doing this without pmp assignments so don't leave the chains
2311 	 * hanging around after we are done with them.
2312 	 *
2313 	 * error	Cumulative error this level only
2314 	 * rup_error	Cumulative error for recursion
2315 	 * tmp_error	Specific non-cumulative recursion error
2316 	 */
2317 	chain = NULL;
2318 	first = 1;
2319 	rup_error = 0;
2320 	error = 0;
2321 
2322 	for (;;) {
2323 		error |= hammer2_chain_scan(parent, &chain, &bref,
2324 					    &first,
2325 					    HAMMER2_LOOKUP_NODATA);
2326 
2327 		/*
2328 		 * Problem during scan or EOF
2329 		 */
2330 		if (error)
2331 			break;
2332 
2333 		/*
2334 		 * If this is a leaf
2335 		 */
2336 		if (chain == NULL) {
2337 			if (bref.mirror_tid > sync_tid) {
2338 				hammer2_freemap_adjust(hmp, &bref,
2339 						     HAMMER2_FREEMAP_DORECOVER);
2340 			}
2341 			continue;
2342 		}
2343 
2344 		/*
2345 		 * This may or may not be a recursive node.
2346 		 */
2347 		atomic_set_int(&chain->flags, HAMMER2_CHAIN_RELEASE);
2348 		if (bref.mirror_tid > sync_tid) {
2349 			++info->depth;
2350 			tmp_error = hammer2_recovery_scan(hmp, chain,
2351 							   info, sync_tid);
2352 			--info->depth;
2353 		} else {
2354 			tmp_error = 0;
2355 		}
2356 
2357 		/*
2358 		 * Flush the recovery at the PFS boundary to stage it for
2359 		 * the final flush of the super-root topology.
2360 		 */
2361 		if (tmp_error == 0 &&
2362 		    (bref.flags & HAMMER2_BREF_FLAG_PFSROOT) &&
2363 		    (chain->flags & HAMMER2_CHAIN_ONFLUSH)) {
2364 			hammer2_flush(chain, HAMMER2_FLUSH_TOP |
2365 					     HAMMER2_FLUSH_ALL);
2366 		}
2367 		rup_error |= tmp_error;
2368 	}
2369 	return ((error | rup_error) & ~HAMMER2_ERROR_EOF);
2370 }
2371 
2372 /*
2373  * This fixes up an error introduced in earlier H2 implementations where
2374  * moving a PFS inode into an indirect block wound up causing the
2375  * HAMMER2_BREF_FLAG_PFSROOT flag in the bref to get cleared.
2376  */
2377 static
2378 int
2379 hammer2_fixup_pfses(hammer2_dev_t *hmp)
2380 {
2381 	const hammer2_inode_data_t *ripdata;
2382 	hammer2_chain_t *parent;
2383 	hammer2_chain_t *chain;
2384 	hammer2_key_t key_next;
2385 	hammer2_pfs_t *spmp;
2386 	int error;
2387 
2388 	error = 0;
2389 
2390 	/*
2391 	 * Lookup mount point under the media-localized super-root.
2392 	 *
2393 	 * cluster->pmp will incorrectly point to spmp and must be fixed
2394 	 * up later on.
2395 	 */
2396 	spmp = hmp->spmp;
2397 	hammer2_inode_lock(spmp->iroot, 0);
2398 	parent = hammer2_inode_chain(spmp->iroot, 0, HAMMER2_RESOLVE_ALWAYS);
2399 	chain = hammer2_chain_lookup(&parent, &key_next,
2400 					 HAMMER2_KEY_MIN, HAMMER2_KEY_MAX,
2401 					 &error, 0);
2402 	while (chain) {
2403 		if (chain->bref.type != HAMMER2_BREF_TYPE_INODE)
2404 			continue;
2405 		if (chain->error) {
2406 			kprintf("I/O error scanning PFS labels\n");
2407 			error |= chain->error;
2408 		} else if ((chain->bref.flags &
2409 			    HAMMER2_BREF_FLAG_PFSROOT) == 0) {
2410 			int error2;
2411 
2412 			ripdata = &chain->data->ipdata;
2413 			hammer2_trans_init(hmp->spmp, 0);
2414 			error2 = hammer2_chain_modify(chain,
2415 						      chain->bref.modify_tid,
2416 						      0, 0);
2417 			if (error2 == 0) {
2418 				kprintf("hammer2: Correct mis-flagged PFS %s\n",
2419 					ripdata->filename);
2420 				chain->bref.flags |= HAMMER2_BREF_FLAG_PFSROOT;
2421 			} else {
2422 				error |= error2;
2423 			}
2424 			hammer2_flush(chain, HAMMER2_FLUSH_TOP |
2425 					     HAMMER2_FLUSH_ALL);
2426 			hammer2_trans_done(hmp->spmp, 0);
2427 		}
2428 		chain = hammer2_chain_next(&parent, chain, &key_next,
2429 					   key_next, HAMMER2_KEY_MAX,
2430 					   &error, 0);
2431 	}
2432 	if (parent) {
2433 		hammer2_chain_unlock(parent);
2434 		hammer2_chain_drop(parent);
2435 	}
2436 	hammer2_inode_unlock(spmp->iroot);
2437 
2438 	return error;
2439 }
2440 
2441 /*
2442  * Sync a mount point; this is called periodically on a per-mount basis from
2443  * the filesystem syncer, and whenever a user issues a sync.
2444  */
2445 int
2446 hammer2_vfs_sync(struct mount *mp, int waitfor)
2447 {
2448 	int error;
2449 
2450 	error = hammer2_vfs_sync_pmp(MPTOPMP(mp), waitfor);
2451 
2452 	return error;
2453 }
2454 
2455 /*
2456  * Because frontend operations lock vnodes before we get a chance to
2457  * lock the related inode, we can't just acquire a vnode lock without
2458  * risking a deadlock.  The frontend may be holding a vnode lock while
2459  * also blocked on our SYNCQ flag while trying to get the inode lock.
2460  *
2461  * To deal with this situation we can check the vnode lock situation
2462  * after locking the inode and perform a work-around.
2463  */
2464 int
2465 hammer2_vfs_sync_pmp(hammer2_pfs_t *pmp, int waitfor)
2466 {
2467 	struct mount *mp;
2468 	/*hammer2_xop_flush_t *xop;*/
2469 	/*struct hammer2_sync_info info;*/
2470 	hammer2_inode_t *ip;
2471 	hammer2_depend_t *depend;
2472 	hammer2_depend_t *depend_next;
2473 	struct vnode *vp;
2474 	uint32_t pass2;
2475 	int error;
2476 	int wakecount;
2477 	int dorestart;
2478 
2479 	mp = pmp->mp;
2480 
2481 	/*
2482 	 * Move all inodes on sideq to syncq.  This will clear sideq.
2483 	 * This should represent all flushable inodes.  These inodes
2484 	 * will already have refs due to being on syncq or sideq.  We
2485 	 * must do this all at once with the spinlock held to ensure that
2486 	 * all inode dependencies are part of the same flush.
2487 	 *
2488 	 * We should be able to do this asynchronously from frontend
2489 	 * operations because we will be locking the inodes later on
2490 	 * to actually flush them, and that will partition any frontend
2491 	 * op using the same inode.  Either it has already locked the
2492 	 * inode and we will block, or it has not yet locked the inode
2493 	 * and it will block until we are finished flushing that inode.
2494 	 *
2495 	 * When restarting, only move the inodes flagged as PASS2 from
2496 	 * SIDEQ to SYNCQ.  PASS2 propagation by inode_lock4() and
2497 	 * inode_depend() are atomic with the spin-lock.
2498 	 */
2499 	hammer2_trans_init(pmp, HAMMER2_TRANS_ISFLUSH);
2500 #ifdef HAMMER2_DEBUG_SYNC
2501 	kprintf("FILESYSTEM SYNC BOUNDARY\n");
2502 #endif
2503 	dorestart = 0;
2504 
2505 	/*
2506 	 * Move inodes from depq to syncq, releasing the related
2507 	 * depend structures.
2508 	 */
2509 restart:
2510 #ifdef HAMMER2_DEBUG_SYNC
2511 	kprintf("FILESYSTEM SYNC RESTART (%d)\n", dorestart);
2512 #endif
2513 	hammer2_trans_setflags(pmp, 0/*HAMMER2_TRANS_COPYQ*/);
2514 	hammer2_trans_clearflags(pmp, HAMMER2_TRANS_RESCAN);
2515 
2516 	/*
2517 	 * Move inodes from depq to syncq.  When restarting, only depq's
2518 	 * marked pass2 are moved.
2519 	 */
2520 	hammer2_spin_ex(&pmp->list_spin);
2521 	depend_next = TAILQ_FIRST(&pmp->depq);
2522 	wakecount = 0;
2523 
2524 	while ((depend = depend_next) != NULL) {
2525 		depend_next = TAILQ_NEXT(depend, entry);
2526 		if (dorestart && depend->pass2 == 0)
2527 			continue;
2528 		TAILQ_FOREACH(ip, &depend->sideq, entry) {
2529 			KKASSERT(ip->flags & HAMMER2_INODE_SIDEQ);
2530 			atomic_set_int(&ip->flags, HAMMER2_INODE_SYNCQ);
2531 			atomic_clear_int(&ip->flags, HAMMER2_INODE_SIDEQ);
2532 			ip->depend = NULL;
2533 		}
2534 
2535 		/*
2536 		 * NOTE: pmp->sideq_count includes both sideq and syncq
2537 		 */
2538 		TAILQ_CONCAT(&pmp->syncq, &depend->sideq, entry);
2539 
2540 		depend->count = 0;
2541 		depend->pass2 = 0;
2542 		TAILQ_REMOVE(&pmp->depq, depend, entry);
2543 	}
2544 
2545 	hammer2_spin_unex(&pmp->list_spin);
2546 	hammer2_trans_clearflags(pmp, /*HAMMER2_TRANS_COPYQ |*/
2547 				      HAMMER2_TRANS_WAITING);
2548 	dorestart = 0;
2549 
2550 	/*
2551 	 * sideq_count may have dropped enough to allow us to unstall
2552 	 * the frontend.
2553 	 */
2554 	hammer2_pfs_memory_wakeup(pmp, 0);
2555 
2556 	/*
2557 	 * Now run through all inodes on syncq.
2558 	 *
2559 	 * Flush transactions only interlock with other flush transactions.
2560 	 * Any conflicting frontend operations will block on the inode, but
2561 	 * may hold a vnode lock while doing so.
2562 	 */
2563 	hammer2_spin_ex(&pmp->list_spin);
2564 	while ((ip = TAILQ_FIRST(&pmp->syncq)) != NULL) {
2565 		/*
2566 		 * Remove the inode from the SYNCQ, transfer the syncq ref
2567 		 * to us.  We must clear SYNCQ to allow any potential
2568 		 * front-end deadlock to proceed.  We must set PASS2 so
2569 		 * the dependency code knows what to do.
2570 		 */
2571 		pass2 = ip->flags;
2572 		cpu_ccfence();
2573 		if (atomic_cmpset_int(&ip->flags,
2574 			      pass2,
2575 			      (pass2 & ~(HAMMER2_INODE_SYNCQ |
2576 					 HAMMER2_INODE_SYNCQ_WAKEUP)) |
2577 			      HAMMER2_INODE_SYNCQ_PASS2) == 0) {
2578 			continue;
2579 		}
2580 		TAILQ_REMOVE(&pmp->syncq, ip, entry);
2581 		--pmp->sideq_count;
2582 		hammer2_spin_unex(&pmp->list_spin);
2583 
2584 		/*
2585 		 * Tickle anyone waiting on ip->flags or the hysteresis
2586 		 * on the dirty inode count.
2587 		 */
2588 		if (pass2 & HAMMER2_INODE_SYNCQ_WAKEUP)
2589 			wakeup(&ip->flags);
2590 		if (++wakecount >= hammer2_limit_dirty_inodes / 20 + 1) {
2591 			wakecount = 0;
2592 			hammer2_pfs_memory_wakeup(pmp, 0);
2593 		}
2594 
2595 		/*
2596 		 * Relock the inode, and we inherit a ref from the above.
2597 		 * We will check for a race after we acquire the vnode.
2598 		 */
2599 		hammer2_mtx_ex(&ip->lock);
2600 
2601 		/*
2602 		 * We need the vp in order to vfsync() dirty buffers, so if
2603 		 * one isn't attached we can skip it.
2604 		 *
2605 		 * Ordering the inode lock and then the vnode lock has the
2606 		 * potential to deadlock.  If we had left SYNCQ set that could
2607 		 * also deadlock us against the frontend even if we don't hold
2608 		 * any locks, but the latter is not a problem now since we
2609 		 * cleared it.  igetv will temporarily release the inode lock
2610 		 * in a safe manner to work-around the deadlock.
2611 		 *
2612 		 * Unfortunately it is still possible to deadlock when the
2613 		 * frontend obtains multiple inode locks, because all the
2614 		 * related vnodes are already locked (nor can the vnode locks
2615 		 * be released and reacquired without messing up RECLAIM and
2616 		 * INACTIVE sequencing).
2617 		 *
2618 		 * The solution for now is to move the vp back onto SIDEQ
2619 		 * and set dorestart, which will restart the flush after we
2620 		 * exhaust the current SYNCQ.  Note that additional
2621 		 * dependencies may build up, so we definitely need to move
2622 		 * the whole SIDEQ back to SYNCQ when we restart.
2623 		 */
2624 		vp = ip->vp;
2625 		if (vp) {
2626 			if (vget(vp, LK_EXCLUSIVE|LK_NOWAIT)) {
2627 				/*
2628 				 * Failed to get the vnode, requeue the inode
2629 				 * (PASS2 is already set so it will be found
2630 				 * again on the restart).
2631 				 *
2632 				 * Then unlock, possibly sleep, and retry
2633 				 * later.  We sleep if PASS2 was *previously*
2634 				 * set, before we set it again above.
2635 				 */
2636 				vp = NULL;
2637 				dorestart = 1;
2638 #ifdef HAMMER2_DEBUG_SYNC
2639 				kprintf("inum %ld (sync delayed by vnode)\n",
2640 					(long)ip->meta.inum);
2641 #endif
2642 				hammer2_inode_delayed_sideq(ip);
2643 
2644 				hammer2_mtx_unlock(&ip->lock);
2645 				hammer2_inode_drop(ip);
2646 
2647 				if (pass2 & HAMMER2_INODE_SYNCQ_PASS2) {
2648 					tsleep(&dorestart, 0, "h2syndel", 2);
2649 				}
2650 				hammer2_spin_ex(&pmp->list_spin);
2651 				continue;
2652 			}
2653 		} else {
2654 			vp = NULL;
2655 		}
2656 
2657 		/*
2658 		 * If the inode wound up on a SIDEQ again it will already be
2659 		 * prepped for another PASS2.  In this situation if we flush
2660 		 * it now we will just wind up flushing it again in the same
2661 		 * syncer run, so we might as well not flush it now.
2662 		 */
2663 		if (ip->flags & HAMMER2_INODE_SIDEQ) {
2664 			hammer2_mtx_unlock(&ip->lock);
2665 			hammer2_inode_drop(ip);
2666 			if (vp)
2667 				vput(vp);
2668 			dorestart = 1;
2669 			hammer2_spin_ex(&pmp->list_spin);
2670 			continue;
2671 		}
2672 
2673 		/*
2674 		 * Ok we have the inode exclusively locked and if vp is
2675 		 * not NULL that will also be exclusively locked.  Do the
2676 		 * meat of the flush.
2677 		 *
2678 		 * vp token needed for v_rbdirty_tree check / vclrisdirty
2679 		 * sequencing.  Though we hold the vnode exclusively so
2680 		 * we shouldn't need to hold the token also in this case.
2681 		 */
2682 		if (vp) {
2683 			vfsync(vp, MNT_WAIT, 1, NULL, NULL);
2684 			bio_track_wait(&vp->v_track_write, 0, 0); /* XXX */
2685 		}
2686 
2687 		/*
2688 		 * If the inode has not yet been inserted into the tree
2689 		 * we must do so.  Then sync and flush it.  The flush should
2690 		 * update the parent.
2691 		 */
2692 		if (ip->flags & HAMMER2_INODE_DELETING) {
2693 #ifdef HAMMER2_DEBUG_SYNC
2694 			kprintf("inum %ld destroy\n", (long)ip->meta.inum);
2695 #endif
2696 			hammer2_inode_chain_des(ip);
2697 			atomic_add_long(&hammer2_iod_inode_deletes, 1);
2698 		} else if (ip->flags & HAMMER2_INODE_CREATING) {
2699 #ifdef HAMMER2_DEBUG_SYNC
2700 			kprintf("inum %ld insert\n", (long)ip->meta.inum);
2701 #endif
2702 			hammer2_inode_chain_ins(ip);
2703 			atomic_add_long(&hammer2_iod_inode_creates, 1);
2704 		}
2705 #ifdef HAMMER2_DEBUG_SYNC
2706 		kprintf("inum %ld chain-sync\n", (long)ip->meta.inum);
2707 #endif
2708 
2709 		/*
2710 		 * Because I kinda messed up the design and index the inodes
2711 		 * under the root inode, along side the directory entries,
2712 		 * we can't flush the inode index under the iroot until the
2713 		 * end.  If we do it now we might miss effects created by
2714 		 * other inodes on the SYNCQ.
2715 		 *
2716 		 * Do a normal (non-FSSYNC) flush instead, which allows the
2717 		 * vnode code to work the same.  We don't want to force iroot
2718 		 * back onto the SIDEQ, and we also don't want the flush code
2719 		 * to update pfs_iroot_blocksets until the final flush later.
2720 		 *
2721 		 * XXX at the moment this will likely result in a double-flush
2722 		 * of the iroot chain.
2723 		 */
2724 		hammer2_inode_chain_sync(ip);
2725 		if (ip == pmp->iroot) {
2726 			hammer2_inode_chain_flush(ip, HAMMER2_XOP_INODE_STOP);
2727 		} else {
2728 			hammer2_inode_chain_flush(ip, HAMMER2_XOP_INODE_STOP |
2729 						      HAMMER2_XOP_FSSYNC);
2730 		}
2731 		if (vp) {
2732 			lwkt_gettoken(&vp->v_token);
2733 			if ((ip->flags & (HAMMER2_INODE_MODIFIED |
2734 					  HAMMER2_INODE_RESIZED |
2735 					  HAMMER2_INODE_DIRTYDATA)) == 0 &&
2736 			    RB_EMPTY(&vp->v_rbdirty_tree) &&
2737 			    !bio_track_active(&vp->v_track_write)) {
2738 				vclrisdirty(vp);
2739 			} else {
2740 				hammer2_inode_delayed_sideq(ip);
2741 			}
2742 			lwkt_reltoken(&vp->v_token);
2743 			vput(vp);
2744 			vp = NULL;	/* safety */
2745 		}
2746 		atomic_clear_int(&ip->flags, HAMMER2_INODE_SYNCQ_PASS2);
2747 		hammer2_inode_unlock(ip);	/* unlock+drop */
2748 		/* ip pointer invalid */
2749 
2750 		/*
2751 		 * If the inode got dirted after we dropped our locks,
2752 		 * it will have already been moved back to the SIDEQ.
2753 		 */
2754 		hammer2_spin_ex(&pmp->list_spin);
2755 	}
2756 	hammer2_spin_unex(&pmp->list_spin);
2757 	hammer2_pfs_memory_wakeup(pmp, 0);
2758 
2759 	if (dorestart || (pmp->trans.flags & HAMMER2_TRANS_RESCAN)) {
2760 #ifdef HAMMER2_DEBUG_SYNC
2761 		kprintf("FILESYSTEM SYNC STAGE 1 RESTART\n");
2762 		/*tsleep(&dorestart, 0, "h2STG1-R", hz*20);*/
2763 #endif
2764 		dorestart = 1;
2765 		goto restart;
2766 	}
2767 #ifdef HAMMER2_DEBUG_SYNC
2768 	kprintf("FILESYSTEM SYNC STAGE 2 BEGIN\n");
2769 	/*tsleep(&dorestart, 0, "h2STG2", hz*20);*/
2770 #endif
2771 
2772 	/*
2773 	 * We have to flush the PFS root last, even if it does not appear to
2774 	 * be dirty, because all the inodes in the PFS are indexed under it.
2775 	 * The normal flushing of iroot above would only occur if directory
2776 	 * entries under the root were changed.
2777 	 *
2778 	 * Specifying VOLHDR will cause an additionl flush of hmp->spmp
2779 	 * for the media making up the cluster.
2780 	 */
2781 	if ((ip = pmp->iroot) != NULL) {
2782 		hammer2_inode_ref(ip);
2783 		hammer2_mtx_ex(&ip->lock);
2784 		hammer2_inode_chain_sync(ip);
2785 		hammer2_inode_chain_flush(ip, HAMMER2_XOP_INODE_STOP |
2786 					      HAMMER2_XOP_FSSYNC |
2787 					      HAMMER2_XOP_VOLHDR);
2788 		hammer2_inode_unlock(ip);	/* unlock+drop */
2789 	}
2790 #ifdef HAMMER2_DEBUG_SYNC
2791 	kprintf("FILESYSTEM SYNC STAGE 2 DONE\n");
2792 #endif
2793 
2794 	/*
2795 	 * device bioq sync
2796 	 */
2797 	hammer2_bioq_sync(pmp);
2798 
2799 #if 0
2800 	/*
2801 	 * Generally speaking we now want to flush the media topology from
2802 	 * the iroot through to the inodes.  The flush stops at any inode
2803 	 * boundary, which allows the frontend to continue running concurrent
2804 	 * modifying operations on inodes (including kernel flushes of
2805 	 * buffers) without interfering with the main sync.
2806 	 *
2807 	 * Use the XOP interface to concurrently flush all nodes to
2808 	 * synchronize the PFSROOT subtopology to the media.  A standard
2809 	 * end-of-scan ENOENT error indicates cluster sufficiency.
2810 	 *
2811 	 * Note that this flush will not be visible on crash recovery until
2812 	 * we flush the super-root topology in the next loop.
2813 	 *
2814 	 * XXX For now wait for all flushes to complete.
2815 	 */
2816 	if (mp && (ip = pmp->iroot) != NULL) {
2817 		/*
2818 		 * If unmounting try to flush everything including any
2819 		 * sub-trees under inodes, just in case there is dangling
2820 		 * modified data, as a safety.  Otherwise just flush up to
2821 		 * the inodes in this stage.
2822 		 */
2823 		kprintf("MP & IROOT\n");
2824 #ifdef HAMMER2_DEBUG_SYNC
2825 		kprintf("FILESYSTEM SYNC STAGE 3 IROOT BEGIN\n");
2826 #endif
2827 		if (mp->mnt_kern_flag & MNTK_UNMOUNT) {
2828 			xop = hammer2_xop_alloc(ip, HAMMER2_XOP_MODIFYING |
2829 						    HAMMER2_XOP_VOLHDR |
2830 						    HAMMER2_XOP_FSSYNC |
2831 						    HAMMER2_XOP_INODE_STOP);
2832 		} else {
2833 			xop = hammer2_xop_alloc(ip, HAMMER2_XOP_MODIFYING |
2834 						    HAMMER2_XOP_INODE_STOP |
2835 						    HAMMER2_XOP_VOLHDR |
2836 						    HAMMER2_XOP_FSSYNC |
2837 						    HAMMER2_XOP_INODE_STOP);
2838 		}
2839 		hammer2_xop_start(&xop->head, &hammer2_inode_flush_desc);
2840 		error = hammer2_xop_collect(&xop->head,
2841 					    HAMMER2_XOP_COLLECT_WAITALL);
2842 		hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP);
2843 #ifdef HAMMER2_DEBUG_SYNC
2844 		kprintf("FILESYSTEM SYNC STAGE 3 IROOT END\n");
2845 #endif
2846 		if (error == HAMMER2_ERROR_ENOENT)
2847 			error = 0;
2848 		else
2849 			error = hammer2_error_to_errno(error);
2850 	} else {
2851 		error = 0;
2852 	}
2853 #endif
2854 	error = 0;	/* XXX */
2855 	hammer2_trans_done(pmp, HAMMER2_TRANS_ISFLUSH);
2856 
2857 	return (error);
2858 }
2859 
2860 static
2861 int
2862 hammer2_vfs_vptofh(struct vnode *vp, struct fid *fhp)
2863 {
2864 	hammer2_inode_t *ip;
2865 
2866 	KKASSERT(MAXFIDSZ >= 16);
2867 	ip = VTOI(vp);
2868 	fhp->fid_len = offsetof(struct fid, fid_data[16]);
2869 	fhp->fid_ext = 0;
2870 	((hammer2_tid_t *)fhp->fid_data)[0] = ip->meta.inum;
2871 	((hammer2_tid_t *)fhp->fid_data)[1] = 0;
2872 
2873 	return 0;
2874 }
2875 
2876 static
2877 int
2878 hammer2_vfs_fhtovp(struct mount *mp, struct vnode *rootvp,
2879 	       struct fid *fhp, struct vnode **vpp)
2880 {
2881 	hammer2_pfs_t *pmp;
2882 	hammer2_tid_t inum;
2883 	int error;
2884 
2885 	pmp = MPTOPMP(mp);
2886 	inum = ((hammer2_tid_t *)fhp->fid_data)[0] & HAMMER2_DIRHASH_USERMSK;
2887 	if (vpp) {
2888 		if (inum == 1)
2889 			error = hammer2_vfs_root(mp, vpp);
2890 		else
2891 			error = hammer2_vfs_vget(mp, NULL, inum, vpp);
2892 	} else {
2893 		error = 0;
2894 	}
2895 	if (error)
2896 		kprintf("fhtovp: %016jx -> %p, %d\n", inum, *vpp, error);
2897 	return error;
2898 }
2899 
2900 static
2901 int
2902 hammer2_vfs_checkexp(struct mount *mp, struct sockaddr *nam,
2903 		 int *exflagsp, struct ucred **credanonp)
2904 {
2905 	hammer2_pfs_t *pmp;
2906 	struct netcred *np;
2907 	int error;
2908 
2909 	pmp = MPTOPMP(mp);
2910 	np = vfs_export_lookup(mp, &pmp->export, nam);
2911 	if (np) {
2912 		*exflagsp = np->netc_exflags;
2913 		*credanonp = &np->netc_anon;
2914 		error = 0;
2915 	} else {
2916 		error = EACCES;
2917 	}
2918 	return error;
2919 }
2920 
2921 /*
2922  * This handles hysteresis on regular file flushes.  Because the BIOs are
2923  * routed to a thread it is possible for an excessive number to build up
2924  * and cause long front-end stalls long before the runningbuffspace limit
2925  * is hit, so we implement hammer2_flush_pipe to control the
2926  * hysteresis.
2927  *
2928  * This is a particular problem when compression is used.
2929  */
2930 void
2931 hammer2_lwinprog_ref(hammer2_pfs_t *pmp)
2932 {
2933 	atomic_add_int(&pmp->count_lwinprog, 1);
2934 }
2935 
2936 void
2937 hammer2_lwinprog_drop(hammer2_pfs_t *pmp)
2938 {
2939 	int lwinprog;
2940 
2941 	lwinprog = atomic_fetchadd_int(&pmp->count_lwinprog, -1);
2942 	if ((lwinprog & HAMMER2_LWINPROG_WAITING) &&
2943 	    (lwinprog & HAMMER2_LWINPROG_MASK) <= hammer2_flush_pipe * 2 / 3) {
2944 		atomic_clear_int(&pmp->count_lwinprog,
2945 				 HAMMER2_LWINPROG_WAITING);
2946 		wakeup(&pmp->count_lwinprog);
2947 	}
2948 	if ((lwinprog & HAMMER2_LWINPROG_WAITING0) &&
2949 	    (lwinprog & HAMMER2_LWINPROG_MASK) <= 0) {
2950 		atomic_clear_int(&pmp->count_lwinprog,
2951 				 HAMMER2_LWINPROG_WAITING0);
2952 		wakeup(&pmp->count_lwinprog);
2953 	}
2954 }
2955 
2956 void
2957 hammer2_lwinprog_wait(hammer2_pfs_t *pmp, int flush_pipe)
2958 {
2959 	int lwinprog;
2960 	int lwflag = (flush_pipe) ? HAMMER2_LWINPROG_WAITING :
2961 				    HAMMER2_LWINPROG_WAITING0;
2962 
2963 	for (;;) {
2964 		lwinprog = pmp->count_lwinprog;
2965 		cpu_ccfence();
2966 		if ((lwinprog & HAMMER2_LWINPROG_MASK) <= flush_pipe)
2967 			break;
2968 		tsleep_interlock(&pmp->count_lwinprog, 0);
2969 		atomic_set_int(&pmp->count_lwinprog, lwflag);
2970 		lwinprog = pmp->count_lwinprog;
2971 		if ((lwinprog & HAMMER2_LWINPROG_MASK) <= flush_pipe)
2972 			break;
2973 		tsleep(&pmp->count_lwinprog, PINTERLOCKED, "h2wpipe", hz);
2974 	}
2975 }
2976 
2977 /*
2978  * It is possible for an excessive number of dirty chains or dirty inodes
2979  * to build up.  When this occurs we start an asynchronous filesystem sync.
2980  * If the level continues to build up, we stall, waiting for it to drop,
2981  * with some hysteresis.
2982  *
2983  * This relies on the kernel calling hammer2_vfs_modifying() prior to
2984  * obtaining any vnode locks before making a modifying VOP call.
2985  */
2986 static int
2987 hammer2_vfs_modifying(struct mount *mp)
2988 {
2989 	if (mp->mnt_flag & MNT_RDONLY)
2990 		return EROFS;
2991 	hammer2_pfs_memory_wait(MPTOPMP(mp));
2992 
2993 	return 0;
2994 }
2995 
2996 /*
2997  * Initiate an asynchronous filesystem sync and, with hysteresis,
2998  * stall if the internal data structure count becomes too bloated.
2999  */
3000 void
3001 hammer2_pfs_memory_wait(hammer2_pfs_t *pmp)
3002 {
3003 	uint32_t waiting;
3004 	int pcatch;
3005 	int error;
3006 
3007 	if (pmp == NULL || pmp->mp == NULL)
3008 		return;
3009 
3010 	for (;;) {
3011 		waiting = pmp->inmem_dirty_chains & HAMMER2_DIRTYCHAIN_MASK;
3012 		cpu_ccfence();
3013 
3014 		/*
3015 		 * Start the syncer running at 1/2 the limit
3016 		 */
3017 		if (waiting > hammer2_limit_dirty_chains / 2 ||
3018 		    pmp->sideq_count > hammer2_limit_dirty_inodes / 2) {
3019 			trigger_syncer(pmp->mp);
3020 		}
3021 
3022 		/*
3023 		 * Stall at the limit waiting for the counts to drop.
3024 		 * This code will typically be woken up once the count
3025 		 * drops below 3/4 the limit, or in one second.
3026 		 */
3027 		if (waiting < hammer2_limit_dirty_chains &&
3028 		    pmp->sideq_count < hammer2_limit_dirty_inodes) {
3029 			break;
3030 		}
3031 
3032 		pcatch = curthread->td_proc ? PCATCH : 0;
3033 
3034 		tsleep_interlock(&pmp->inmem_dirty_chains, pcatch);
3035 		atomic_set_int(&pmp->inmem_dirty_chains,
3036 			       HAMMER2_DIRTYCHAIN_WAITING);
3037 		if (waiting < hammer2_limit_dirty_chains &&
3038 		    pmp->sideq_count < hammer2_limit_dirty_inodes) {
3039 			break;
3040 		}
3041 		trigger_syncer(pmp->mp);
3042 		error = tsleep(&pmp->inmem_dirty_chains, PINTERLOCKED | pcatch,
3043 			       "h2memw", hz);
3044 		if (error == ERESTART)
3045 			break;
3046 	}
3047 }
3048 
3049 /*
3050  * Wake up any stalled frontend ops waiting, with hysteresis, using
3051  * 2/3 of the limit.
3052  */
3053 void
3054 hammer2_pfs_memory_wakeup(hammer2_pfs_t *pmp, int count)
3055 {
3056 	uint32_t waiting;
3057 
3058 	if (pmp) {
3059 		waiting = atomic_fetchadd_int(&pmp->inmem_dirty_chains, count);
3060 		/* don't need --waiting to test flag */
3061 
3062 		if ((waiting & HAMMER2_DIRTYCHAIN_WAITING) &&
3063 		    (pmp->inmem_dirty_chains & HAMMER2_DIRTYCHAIN_MASK) <=
3064 		    hammer2_limit_dirty_chains * 2 / 3 &&
3065 		    pmp->sideq_count <= hammer2_limit_dirty_inodes * 2 / 3) {
3066 			atomic_clear_int(&pmp->inmem_dirty_chains,
3067 					 HAMMER2_DIRTYCHAIN_WAITING);
3068 			wakeup(&pmp->inmem_dirty_chains);
3069 		}
3070 	}
3071 }
3072 
3073 void
3074 hammer2_pfs_memory_inc(hammer2_pfs_t *pmp)
3075 {
3076 	if (pmp) {
3077 		atomic_add_int(&pmp->inmem_dirty_chains, 1);
3078 	}
3079 }
3080 
3081 /*
3082  * Volume header data locks
3083  */
3084 void
3085 hammer2_voldata_lock(hammer2_dev_t *hmp)
3086 {
3087 	lockmgr(&hmp->vollk, LK_EXCLUSIVE);
3088 }
3089 
3090 void
3091 hammer2_voldata_unlock(hammer2_dev_t *hmp)
3092 {
3093 	lockmgr(&hmp->vollk, LK_RELEASE);
3094 }
3095 
3096 void
3097 hammer2_voldata_modify(hammer2_dev_t *hmp)
3098 {
3099 	if ((hmp->vchain.flags & HAMMER2_CHAIN_MODIFIED) == 0) {
3100 		atomic_add_long(&hammer2_count_modified_chains, 1);
3101 		atomic_set_int(&hmp->vchain.flags, HAMMER2_CHAIN_MODIFIED);
3102 		hammer2_pfs_memory_inc(hmp->vchain.pmp);
3103 	}
3104 }
3105 
3106 /*
3107  * Returns 0 if the filesystem has tons of free space
3108  * Returns 1 if the filesystem has less than 10% remaining
3109  * Returns 2 if the filesystem has less than 2%/5% (user/root) remaining.
3110  */
3111 int
3112 hammer2_vfs_enospace(hammer2_inode_t *ip, off_t bytes, struct ucred *cred)
3113 {
3114 	hammer2_pfs_t *pmp;
3115 	hammer2_dev_t *hmp;
3116 	hammer2_off_t free_reserved;
3117 	hammer2_off_t free_nominal;
3118 	int i;
3119 
3120 	pmp = ip->pmp;
3121 
3122 	if (pmp->free_ticks == 0 || pmp->free_ticks != ticks) {
3123 		free_reserved = HAMMER2_SEGSIZE;
3124 		free_nominal = 0x7FFFFFFFFFFFFFFFLLU;
3125 		for (i = 0; i < pmp->iroot->cluster.nchains; ++i) {
3126 			hmp = pmp->pfs_hmps[i];
3127 			if (hmp == NULL)
3128 				continue;
3129 			if (pmp->pfs_types[i] != HAMMER2_PFSTYPE_MASTER &&
3130 			    pmp->pfs_types[i] != HAMMER2_PFSTYPE_SOFT_MASTER)
3131 				continue;
3132 
3133 			if (free_nominal > hmp->voldata.allocator_free)
3134 				free_nominal = hmp->voldata.allocator_free;
3135 			if (free_reserved < hmp->free_reserved)
3136 				free_reserved = hmp->free_reserved;
3137 		}
3138 
3139 		/*
3140 		 * SMP races ok
3141 		 */
3142 		pmp->free_reserved = free_reserved;
3143 		pmp->free_nominal = free_nominal;
3144 		pmp->free_ticks = ticks;
3145 	} else {
3146 		free_reserved = pmp->free_reserved;
3147 		free_nominal = pmp->free_nominal;
3148 	}
3149 	if (cred && cred->cr_uid != 0) {
3150 		if ((int64_t)(free_nominal - bytes) <
3151 		    (int64_t)free_reserved) {
3152 			return 2;
3153 		}
3154 	} else {
3155 		if ((int64_t)(free_nominal - bytes) <
3156 		    (int64_t)free_reserved / 2) {
3157 			return 2;
3158 		}
3159 	}
3160 	if ((int64_t)(free_nominal - bytes) < (int64_t)free_reserved * 2)
3161 		return 1;
3162 	return 0;
3163 }
3164 
3165 /*
3166  * Debugging
3167  */
3168 void
3169 hammer2_dump_chain(hammer2_chain_t *chain, int tab, int bi, int *countp,
3170 		   char pfx, u_int flags)
3171 {
3172 	hammer2_chain_t *scan;
3173 	hammer2_chain_t *parent;
3174 
3175 	--*countp;
3176 	if (*countp == 0) {
3177 		kprintf("%*.*s...\n", tab, tab, "");
3178 		return;
3179 	}
3180 	if (*countp < 0)
3181 		return;
3182 	kprintf("%*.*s%c-chain %p %s.%-3d %016jx %016jx/%-2d mir=%016jx\n",
3183 		tab, tab, "", pfx, chain,
3184 		hammer2_bref_type_str(chain->bref.type), bi,
3185 		chain->bref.data_off, chain->bref.key, chain->bref.keybits,
3186 		chain->bref.mirror_tid);
3187 
3188 	kprintf("%*.*s      [%08x] (%s) refs=%d",
3189 		tab, tab, "",
3190 		chain->flags,
3191 		((chain->bref.type == HAMMER2_BREF_TYPE_INODE &&
3192 		chain->data) ?  (char *)chain->data->ipdata.filename : "?"),
3193 		chain->refs);
3194 
3195 	parent = chain->parent;
3196 	if (parent)
3197 		kprintf("\n%*.*s      p=%p [pflags %08x prefs %d]",
3198 			tab, tab, "",
3199 			parent, parent->flags, parent->refs);
3200 	if (RB_EMPTY(&chain->core.rbtree)) {
3201 		kprintf("\n");
3202 	} else {
3203 		int bi = 0;
3204 		kprintf(" {\n");
3205 		RB_FOREACH(scan, hammer2_chain_tree, &chain->core.rbtree) {
3206 			if ((scan->flags & flags) || flags == (u_int)-1) {
3207 				hammer2_dump_chain(scan, tab + 4, bi, countp,
3208 						   'a', flags);
3209 			}
3210 			bi++;
3211 		}
3212 		if (chain->bref.type == HAMMER2_BREF_TYPE_INODE && chain->data)
3213 			kprintf("%*.*s}(%s)\n", tab, tab, "",
3214 				chain->data->ipdata.filename);
3215 		else
3216 			kprintf("%*.*s}\n", tab, tab, "");
3217 	}
3218 }
3219