Merge branch 'vendor/LESS'
[dragonfly.git] / sys / vfs / hammer2 / hammer2_vfsops.c
1 /*
2  * Copyright (c) 2011-2015 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/namei.h>
51 #include <sys/mountctl.h>
52 #include <sys/dirent.h>
53 #include <sys/uio.h>
54
55 #include <sys/mutex.h>
56 #include <sys/mutex2.h>
57
58 #include "hammer2.h"
59 #include "hammer2_disk.h"
60 #include "hammer2_mount.h"
61 #include "hammer2_lz4.h"
62
63 #include "zlib/hammer2_zlib.h"
64
65 #define REPORT_REFS_ERRORS 1    /* XXX remove me */
66
67 MALLOC_DEFINE(M_OBJCACHE, "objcache", "Object Cache");
68
69 struct hammer2_sync_info {
70         int error;
71         int waitfor;
72 };
73
74 TAILQ_HEAD(hammer2_mntlist, hammer2_dev);
75 TAILQ_HEAD(hammer2_pfslist, hammer2_pfs);
76 static struct hammer2_mntlist hammer2_mntlist;
77 static struct hammer2_pfslist hammer2_pfslist;
78 static struct lock hammer2_mntlk;
79
80 int hammer2_debug;
81 int hammer2_cluster_read = 4;           /* physical read-ahead */
82 int hammer2_cluster_write = 0;          /* bdwrite() so later inval works */
83 int hammer2_dedup_enable = 1;
84 int hammer2_inval_enable = 0;
85 int hammer2_flush_pipe = 100;
86 int hammer2_synchronous_flush = 1;
87 int hammer2_dio_count;
88 long hammer2_chain_allocs;
89 long hammer2_chain_frees;
90 long hammer2_limit_dirty_chains;
91 long hammer2_count_modified_chains;
92 long hammer2_iod_invals;
93 long hammer2_iod_file_read;
94 long hammer2_iod_meta_read;
95 long hammer2_iod_indr_read;
96 long hammer2_iod_fmap_read;
97 long hammer2_iod_volu_read;
98 long hammer2_iod_file_write;
99 long hammer2_iod_file_wembed;
100 long hammer2_iod_file_wzero;
101 long hammer2_iod_file_wdedup;
102 long hammer2_iod_meta_write;
103 long hammer2_iod_indr_write;
104 long hammer2_iod_fmap_write;
105 long hammer2_iod_volu_write;
106
107 MALLOC_DECLARE(M_HAMMER2_CBUFFER);
108 MALLOC_DEFINE(M_HAMMER2_CBUFFER, "HAMMER2-compbuffer",
109                 "Buffer used for compression.");
110
111 MALLOC_DECLARE(M_HAMMER2_DEBUFFER);
112 MALLOC_DEFINE(M_HAMMER2_DEBUFFER, "HAMMER2-decompbuffer",
113                 "Buffer used for decompression.");
114
115 SYSCTL_NODE(_vfs, OID_AUTO, hammer2, CTLFLAG_RW, 0, "HAMMER2 filesystem");
116
117 SYSCTL_INT(_vfs_hammer2, OID_AUTO, debug, CTLFLAG_RW,
118            &hammer2_debug, 0, "");
119 SYSCTL_INT(_vfs_hammer2, OID_AUTO, cluster_read, CTLFLAG_RW,
120            &hammer2_cluster_read, 0, "");
121 SYSCTL_INT(_vfs_hammer2, OID_AUTO, cluster_write, CTLFLAG_RW,
122            &hammer2_cluster_write, 0, "");
123 SYSCTL_INT(_vfs_hammer2, OID_AUTO, dedup_enable, CTLFLAG_RW,
124            &hammer2_dedup_enable, 0, "");
125 SYSCTL_INT(_vfs_hammer2, OID_AUTO, inval_enable, CTLFLAG_RW,
126            &hammer2_inval_enable, 0, "");
127 SYSCTL_INT(_vfs_hammer2, OID_AUTO, flush_pipe, CTLFLAG_RW,
128            &hammer2_flush_pipe, 0, "");
129 SYSCTL_INT(_vfs_hammer2, OID_AUTO, synchronous_flush, CTLFLAG_RW,
130            &hammer2_synchronous_flush, 0, "");
131 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, chain_allocs, CTLFLAG_RW,
132            &hammer2_chain_allocs, 0, "");
133 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, chain_frees, CTLFLAG_RW,
134            &hammer2_chain_frees, 0, "");
135 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, limit_dirty_chains, CTLFLAG_RW,
136            &hammer2_limit_dirty_chains, 0, "");
137 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, count_modified_chains, CTLFLAG_RW,
138            &hammer2_count_modified_chains, 0, "");
139 SYSCTL_INT(_vfs_hammer2, OID_AUTO, dio_count, CTLFLAG_RD,
140            &hammer2_dio_count, 0, "");
141
142 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_invals, CTLFLAG_RW,
143            &hammer2_iod_invals, 0, "");
144 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_read, CTLFLAG_RW,
145            &hammer2_iod_file_read, 0, "");
146 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_meta_read, CTLFLAG_RW,
147            &hammer2_iod_meta_read, 0, "");
148 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_indr_read, CTLFLAG_RW,
149            &hammer2_iod_indr_read, 0, "");
150 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_fmap_read, CTLFLAG_RW,
151            &hammer2_iod_fmap_read, 0, "");
152 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_volu_read, CTLFLAG_RW,
153            &hammer2_iod_volu_read, 0, "");
154
155 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_write, CTLFLAG_RW,
156            &hammer2_iod_file_write, 0, "");
157 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_wembed, CTLFLAG_RW,
158            &hammer2_iod_file_wembed, 0, "");
159 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_wzero, CTLFLAG_RW,
160            &hammer2_iod_file_wzero, 0, "");
161 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_wdedup, CTLFLAG_RW,
162            &hammer2_iod_file_wdedup, 0, "");
163 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_meta_write, CTLFLAG_RW,
164            &hammer2_iod_meta_write, 0, "");
165 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_indr_write, CTLFLAG_RW,
166            &hammer2_iod_indr_write, 0, "");
167 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_fmap_write, CTLFLAG_RW,
168            &hammer2_iod_fmap_write, 0, "");
169 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_volu_write, CTLFLAG_RW,
170            &hammer2_iod_volu_write, 0, "");
171
172 long hammer2_check_icrc32;
173 long hammer2_check_xxhash64;
174 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, check_icrc32, CTLFLAG_RW,
175            &hammer2_check_icrc32, 0, "");
176 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, check_xxhash64, CTLFLAG_RW,
177            &hammer2_check_xxhash64, 0, "");
178
179 static int hammer2_vfs_init(struct vfsconf *conf);
180 static int hammer2_vfs_uninit(struct vfsconf *vfsp);
181 static int hammer2_vfs_mount(struct mount *mp, char *path, caddr_t data,
182                                 struct ucred *cred);
183 static int hammer2_remount(hammer2_dev_t *, struct mount *, char *,
184                                 struct vnode *, struct ucred *);
185 static int hammer2_recovery(hammer2_dev_t *hmp);
186 static int hammer2_vfs_unmount(struct mount *mp, int mntflags);
187 static int hammer2_vfs_root(struct mount *mp, struct vnode **vpp);
188 static int hammer2_vfs_statfs(struct mount *mp, struct statfs *sbp,
189                                 struct ucred *cred);
190 static int hammer2_vfs_statvfs(struct mount *mp, struct statvfs *sbp,
191                                 struct ucred *cred);
192 static int hammer2_vfs_fhtovp(struct mount *mp, struct vnode *rootvp,
193                                 struct fid *fhp, struct vnode **vpp);
194 static int hammer2_vfs_vptofh(struct vnode *vp, struct fid *fhp);
195 static int hammer2_vfs_checkexp(struct mount *mp, struct sockaddr *nam,
196                                 int *exflagsp, struct ucred **credanonp);
197
198 static int hammer2_install_volume_header(hammer2_dev_t *hmp);
199 static int hammer2_sync_scan2(struct mount *mp, struct vnode *vp, void *data);
200
201 static void hammer2_update_pmps(hammer2_dev_t *hmp);
202
203 static void hammer2_mount_helper(struct mount *mp, hammer2_pfs_t *pmp);
204 static void hammer2_unmount_helper(struct mount *mp, hammer2_pfs_t *pmp,
205                                 hammer2_dev_t *hmp);
206
207 /*
208  * HAMMER2 vfs operations.
209  */
210 static struct vfsops hammer2_vfsops = {
211         .vfs_init       = hammer2_vfs_init,
212         .vfs_uninit     = hammer2_vfs_uninit,
213         .vfs_sync       = hammer2_vfs_sync,
214         .vfs_mount      = hammer2_vfs_mount,
215         .vfs_unmount    = hammer2_vfs_unmount,
216         .vfs_root       = hammer2_vfs_root,
217         .vfs_statfs     = hammer2_vfs_statfs,
218         .vfs_statvfs    = hammer2_vfs_statvfs,
219         .vfs_vget       = hammer2_vfs_vget,
220         .vfs_vptofh     = hammer2_vfs_vptofh,
221         .vfs_fhtovp     = hammer2_vfs_fhtovp,
222         .vfs_checkexp   = hammer2_vfs_checkexp
223 };
224
225 MALLOC_DEFINE(M_HAMMER2, "HAMMER2-mount", "");
226
227 VFS_SET(hammer2_vfsops, hammer2, 0);
228 MODULE_VERSION(hammer2, 1);
229
230 static
231 int
232 hammer2_vfs_init(struct vfsconf *conf)
233 {
234         static struct objcache_malloc_args margs_read;
235         static struct objcache_malloc_args margs_write;
236         static struct objcache_malloc_args margs_vop;
237
238         int error;
239
240         error = 0;
241
242         if (HAMMER2_BLOCKREF_BYTES != sizeof(struct hammer2_blockref))
243                 error = EINVAL;
244         if (HAMMER2_INODE_BYTES != sizeof(struct hammer2_inode_data))
245                 error = EINVAL;
246         if (HAMMER2_VOLUME_BYTES != sizeof(struct hammer2_volume_data))
247                 error = EINVAL;
248
249         if (error)
250                 kprintf("HAMMER2 structure size mismatch; cannot continue.\n");
251         
252         margs_read.objsize = 65536;
253         margs_read.mtype = M_HAMMER2_DEBUFFER;
254         
255         margs_write.objsize = 32768;
256         margs_write.mtype = M_HAMMER2_CBUFFER;
257
258         margs_vop.objsize = sizeof(hammer2_xop_t);
259         margs_vop.mtype = M_HAMMER2;
260         
261         /*
262          * Note thaht for the XOPS cache we want backing store allocations
263          * to use M_ZERO.  This is not allowed in objcache_get() (to avoid
264          * confusion), so use the backing store function that does it.  This
265          * means that initial XOPS objects are zerod but REUSED objects are
266          * not.  So we are responsible for cleaning the object up sufficiently
267          * for our needs before objcache_put()ing it back (typically just the
268          * FIFO indices).
269          */
270         cache_buffer_read = objcache_create(margs_read.mtype->ks_shortdesc,
271                                 0, 1, NULL, NULL, NULL,
272                                 objcache_malloc_alloc,
273                                 objcache_malloc_free,
274                                 &margs_read);
275         cache_buffer_write = objcache_create(margs_write.mtype->ks_shortdesc,
276                                 0, 1, NULL, NULL, NULL,
277                                 objcache_malloc_alloc,
278                                 objcache_malloc_free,
279                                 &margs_write);
280         cache_xops = objcache_create(margs_vop.mtype->ks_shortdesc,
281                                 0, 1, NULL, NULL, NULL,
282                                 objcache_malloc_alloc_zero,
283                                 objcache_malloc_free,
284                                 &margs_vop);
285
286
287         lockinit(&hammer2_mntlk, "mntlk", 0, 0);
288         TAILQ_INIT(&hammer2_mntlist);
289         TAILQ_INIT(&hammer2_pfslist);
290
291         hammer2_limit_dirty_chains = desiredvnodes / 10;
292
293         return (error);
294 }
295
296 static
297 int
298 hammer2_vfs_uninit(struct vfsconf *vfsp __unused)
299 {
300         objcache_destroy(cache_buffer_read);
301         objcache_destroy(cache_buffer_write);
302         objcache_destroy(cache_xops);
303         return 0;
304 }
305
306 /*
307  * Core PFS allocator.  Used to allocate the pmp structure for PFS cluster
308  * mounts and the spmp structure for media (hmp) structures.
309  *
310  * pmp->modify_tid tracks new modify_tid transaction ids for front-end
311  * transactions.  Note that synchronization does not use this field.
312  * (typically frontend operations and synchronization cannot run on the
313  * same PFS node at the same time).
314  *
315  * XXX check locking
316  */
317 hammer2_pfs_t *
318 hammer2_pfsalloc(hammer2_chain_t *chain, const hammer2_inode_data_t *ripdata,
319                  hammer2_tid_t modify_tid, hammer2_dev_t *force_local)
320 {
321         hammer2_inode_t *iroot;
322         hammer2_pfs_t *pmp;
323         int count;
324         int i;
325         int j;
326
327         /*
328          * Locate or create the PFS based on the cluster id.  If ripdata
329          * is NULL this is a spmp which is unique and is always allocated.
330          *
331          * If the device is mounted in local mode all PFSs are considered
332          * independent and not part of any cluster (for debugging only).
333          */
334         if (ripdata) {
335                 TAILQ_FOREACH(pmp, &hammer2_pfslist, mntentry) {
336                         if (force_local != pmp->force_local)
337                                 continue;
338                         if (force_local == NULL &&
339                             bcmp(&pmp->pfs_clid, &ripdata->meta.pfs_clid,
340                                  sizeof(pmp->pfs_clid)) == 0) {
341                                         break;
342                         } else if (force_local && pmp->pfs_names[0] &&
343                             strcmp(pmp->pfs_names[0], ripdata->filename) == 0) {
344                                         break;
345                         }
346                 }
347         } else {
348                 pmp = NULL;
349         }
350
351         if (pmp == NULL) {
352                 pmp = kmalloc(sizeof(*pmp), M_HAMMER2, M_WAITOK | M_ZERO);
353                 pmp->force_local = force_local;
354                 hammer2_trans_manage_init(pmp);
355                 kmalloc_create(&pmp->minode, "HAMMER2-inodes");
356                 kmalloc_create(&pmp->mmsg, "HAMMER2-pfsmsg");
357                 lockinit(&pmp->lock, "pfslk", 0, 0);
358                 lockinit(&pmp->lock_nlink, "h2nlink", 0, 0);
359                 spin_init(&pmp->inum_spin, "hm2pfsalloc_inum");
360                 spin_init(&pmp->xop_spin, "h2xop");
361                 spin_init(&pmp->lru_spin, "h2lru");
362                 RB_INIT(&pmp->inum_tree);
363                 TAILQ_INIT(&pmp->sideq);
364                 TAILQ_INIT(&pmp->lru_list);
365                 spin_init(&pmp->list_spin, "hm2pfsalloc_list");
366
367                 /*
368                  * Distribute backend operations to threads
369                  */
370                 for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
371                         for (j = 0; j < HAMMER2_XOPGROUPS +
372                                         HAMMER2_SPECTHREADS; ++j) {
373                                 TAILQ_INIT(&pmp->xopq[i][j]);
374                         }
375                 }
376                 for (i = 0; i < HAMMER2_XOPGROUPS; ++i)
377                         hammer2_xop_group_init(pmp, &pmp->xop_groups[i]);
378
379                 /*
380                  * Save the last media transaction id for the flusher.  Set
381                  * initial 
382                  */
383                 if (ripdata)
384                         pmp->pfs_clid = ripdata->meta.pfs_clid;
385                 TAILQ_INSERT_TAIL(&hammer2_pfslist, pmp, mntentry);
386
387                 /*
388                  * The synchronization thread may start too early, make
389                  * sure it stays frozen until we are ready to let it go.
390                  * XXX
391                  */
392                 /*
393                 pmp->primary_thr.flags = HAMMER2_THREAD_FROZEN |
394                                          HAMMER2_THREAD_REMASTER;
395                 */
396         }
397
398         /*
399          * Create the PFS's root inode.
400          */
401         if ((iroot = pmp->iroot) == NULL) {
402                 iroot = hammer2_inode_get(pmp, NULL, NULL, -1);
403                 pmp->iroot = iroot;
404                 hammer2_inode_ref(iroot);
405                 hammer2_inode_unlock(iroot);
406         }
407
408         /*
409          * Stop here if no chain is passed in.
410          */
411         if (chain == NULL)
412                 goto done;
413
414         /*
415          * When a chain is passed in we must add it to the PFS's root
416          * inode, update pmp->pfs_types[], and update the syncronization
417          * threads.
418          *
419          * When forcing local mode, mark the PFS as a MASTER regardless.
420          *
421          * At the moment empty spots can develop due to removals or failures.
422          * Ultimately we want to re-fill these spots but doing so might
423          * confused running code. XXX
424          */
425         hammer2_inode_ref(iroot);
426         hammer2_mtx_ex(&iroot->lock);
427         j = iroot->cluster.nchains;
428
429         kprintf("add PFS to pmp %p[%d]\n", pmp, j);
430
431         if (j == HAMMER2_MAXCLUSTER) {
432                 kprintf("hammer2_mount: cluster full!\n");
433                 /* XXX fatal error? */
434         } else {
435                 KKASSERT(chain->pmp == NULL);
436                 chain->pmp = pmp;
437                 hammer2_chain_ref(chain);
438                 iroot->cluster.array[j].chain = chain;
439                 if (force_local)
440                         pmp->pfs_types[j] = HAMMER2_PFSTYPE_MASTER;
441                 else
442                         pmp->pfs_types[j] = ripdata->meta.pfs_type;
443                 pmp->pfs_names[j] = kstrdup(ripdata->filename, M_HAMMER2);
444                 pmp->pfs_hmps[j] = chain->hmp;
445
446                 /*
447                  * If the PFS is already mounted we must account
448                  * for the mount_count here.
449                  */
450                 if (pmp->mp)
451                         ++chain->hmp->mount_count;
452
453                 /*
454                  * May have to fixup dirty chain tracking.  Previous
455                  * pmp was NULL so nothing to undo.
456                  */
457                 if (chain->flags & HAMMER2_CHAIN_MODIFIED)
458                         hammer2_pfs_memory_inc(pmp);
459                 ++j;
460         }
461         iroot->cluster.nchains = j;
462
463         /*
464          * Update nmasters from any PFS inode which is part of the cluster.
465          * It is possible that this will result in a value which is too
466          * high.  MASTER PFSs are authoritative for pfs_nmasters and will
467          * override this value later on.
468          *
469          * (This informs us of masters that might not currently be
470          *  discoverable by this mount).
471          */
472         if (ripdata && pmp->pfs_nmasters < ripdata->meta.pfs_nmasters) {
473                 pmp->pfs_nmasters = ripdata->meta.pfs_nmasters;
474         }
475
476         /*
477          * Count visible masters.  Masters are usually added with
478          * ripdata->meta.pfs_nmasters set to 1.  This detects when there
479          * are more (XXX and must update the master inodes).
480          */
481         count = 0;
482         for (i = 0; i < iroot->cluster.nchains; ++i) {
483                 if (pmp->pfs_types[i] == HAMMER2_PFSTYPE_MASTER)
484                         ++count;
485         }
486         if (pmp->pfs_nmasters < count)
487                 pmp->pfs_nmasters = count;
488
489         /*
490          * Create missing synchronization and support threads.
491          *
492          * Single-node masters (including snapshots) have nothing to
493          * synchronize and do not require this thread.
494          *
495          * Multi-node masters or any number of soft masters, slaves, copy,
496          * or other PFS types need the thread.
497          *
498          * Each thread is responsible for its particular cluster index.
499          * We use independent threads so stalls or mismatches related to
500          * any given target do not affect other targets.
501          */
502         for (i = 0; i < iroot->cluster.nchains; ++i) {
503                 /*
504                  * Single-node masters (including snapshots) have nothing
505                  * to synchronize and will make direct xops support calls,
506                  * thus they do not require this thread.
507                  *
508                  * Note that there can be thousands of snapshots.  We do not
509                  * want to create thousands of threads.
510                  */
511                 if (pmp->pfs_nmasters <= 1 &&
512                     pmp->pfs_types[i] == HAMMER2_PFSTYPE_MASTER) {
513                         continue;
514                 }
515
516                 /*
517                  * Sync support thread
518                  */
519                 if (pmp->sync_thrs[i].td == NULL) {
520                         hammer2_thr_create(&pmp->sync_thrs[i], pmp,
521                                            "h2nod", i, -1,
522                                            hammer2_primary_sync_thread);
523                 }
524         }
525
526         /*
527          * Create missing Xop threads
528          */
529         if (pmp->mp)
530                 hammer2_xop_helper_create(pmp);
531
532         hammer2_mtx_unlock(&iroot->lock);
533         hammer2_inode_drop(iroot);
534 done:
535         return pmp;
536 }
537
538 /*
539  * Destroy a PFS, typically only occurs after the last mount on a device
540  * has gone away.
541  */
542 static void
543 hammer2_pfsfree(hammer2_pfs_t *pmp)
544 {
545         hammer2_inode_t *iroot;
546         hammer2_chain_t *chain;
547         int i;
548         int j;
549
550         /*
551          * Cleanup our reference on iroot.  iroot is (should) not be needed
552          * by the flush code.
553          */
554         TAILQ_REMOVE(&hammer2_pfslist, pmp, mntentry);
555
556         iroot = pmp->iroot;
557         if (iroot) {
558                 for (i = 0; i < iroot->cluster.nchains; ++i) {
559                         hammer2_thr_delete(&pmp->sync_thrs[i]);
560                         for (j = 0; j < HAMMER2_XOPGROUPS; ++j)
561                                 hammer2_thr_delete(&pmp->xop_groups[j].thrs[i]);
562                 }
563 #if REPORT_REFS_ERRORS
564                 if (pmp->iroot->refs != 1)
565                         kprintf("PMP->IROOT %p REFS WRONG %d\n",
566                                 pmp->iroot, pmp->iroot->refs);
567 #else
568                 KKASSERT(pmp->iroot->refs == 1);
569 #endif
570                 /* ref for pmp->iroot */
571                 hammer2_inode_drop(pmp->iroot);
572                 pmp->iroot = NULL;
573         }
574
575         /*
576          * Cleanup chains remaining on LRU list.
577          */
578         kprintf("pfsfree: %p lrucount=%d\n", pmp, pmp->lru_count);
579         while ((chain = TAILQ_FIRST(&pmp->lru_list)) != NULL) {
580                 hammer2_chain_ref(chain);
581                 atomic_set_int(&chain->flags, HAMMER2_CHAIN_RELEASE);
582                 hammer2_chain_drop(chain);
583         }
584
585         /*
586          * Free remaining pmp resources
587          */
588         kmalloc_destroy(&pmp->mmsg);
589         kmalloc_destroy(&pmp->minode);
590
591         kfree(pmp, M_HAMMER2);
592 }
593
594 /*
595  * Remove all references to hmp from the pfs list.  Any PFS which becomes
596  * empty is terminated and freed.
597  *
598  * XXX inefficient.
599  */
600 static void
601 hammer2_pfsfree_scan(hammer2_dev_t *hmp)
602 {
603         hammer2_pfs_t *pmp;
604         hammer2_inode_t *iroot;
605         hammer2_chain_t *rchain;
606         int didfreeze;
607         int i;
608         int j;
609
610 again:
611         TAILQ_FOREACH(pmp, &hammer2_pfslist, mntentry) {
612                 if ((iroot = pmp->iroot) == NULL)
613                         continue;
614                 if (hmp->spmp == pmp) {
615                         kprintf("unmount hmp %p remove spmp %p\n",
616                                 hmp, pmp);
617                         hmp->spmp = NULL;
618                 }
619
620                 /*
621                  * Determine if this PFS is affected.  If it is we must
622                  * freeze all management threads and lock its iroot.
623                  *
624                  * Freezing a management thread forces it idle, operations
625                  * in-progress will be aborted and it will have to start
626                  * over again when unfrozen, or exit if told to exit.
627                  */
628                 for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
629                         if (pmp->pfs_hmps[i] == hmp)
630                                 break;
631                 }
632                 if (i != HAMMER2_MAXCLUSTER) {
633                         /*
634                          * Make sure all synchronization threads are locked
635                          * down.
636                          */
637                         for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
638                                 if (pmp->pfs_hmps[i] == NULL)
639                                         continue;
640                                 hammer2_thr_freeze_async(&pmp->sync_thrs[i]);
641                                 for (j = 0; j < HAMMER2_XOPGROUPS; ++j) {
642                                         hammer2_thr_freeze_async(
643                                                 &pmp->xop_groups[j].thrs[i]);
644                                 }
645                         }
646                         for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
647                                 if (pmp->pfs_hmps[i] == NULL)
648                                         continue;
649                                 hammer2_thr_freeze(&pmp->sync_thrs[i]);
650                                 for (j = 0; j < HAMMER2_XOPGROUPS; ++j) {
651                                         hammer2_thr_freeze(
652                                                 &pmp->xop_groups[j].thrs[i]);
653                                 }
654                         }
655
656                         /*
657                          * Lock the inode and clean out matching chains.
658                          * Note that we cannot use hammer2_inode_lock_*()
659                          * here because that would attempt to validate the
660                          * cluster that we are in the middle of ripping
661                          * apart.
662                          *
663                          * WARNING! We are working directly on the inodes
664                          *          embedded cluster.
665                          */
666                         hammer2_mtx_ex(&iroot->lock);
667
668                         /*
669                          * Remove the chain from matching elements of the PFS.
670                          */
671                         for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
672                                 if (pmp->pfs_hmps[i] != hmp)
673                                         continue;
674                                 hammer2_thr_delete(&pmp->sync_thrs[i]);
675                                 for (j = 0; j < HAMMER2_XOPGROUPS; ++j) {
676                                         hammer2_thr_delete(
677                                                 &pmp->xop_groups[j].thrs[i]);
678                                 }
679                                 rchain = iroot->cluster.array[i].chain;
680                                 iroot->cluster.array[i].chain = NULL;
681                                 pmp->pfs_types[i] = 0;
682                                 if (pmp->pfs_names[i]) {
683                                         kfree(pmp->pfs_names[i], M_HAMMER2);
684                                         pmp->pfs_names[i] = NULL;
685                                 }
686                                 if (rchain) {
687                                         hammer2_chain_drop(rchain);
688                                         /* focus hint */
689                                         if (iroot->cluster.focus == rchain)
690                                                 iroot->cluster.focus = NULL;
691                                 }
692                                 pmp->pfs_hmps[i] = NULL;
693                         }
694                         hammer2_mtx_unlock(&iroot->lock);
695                         didfreeze = 1;  /* remaster, unfreeze down below */
696                 } else {
697                         didfreeze = 0;
698                 }
699
700                 /*
701                  * Cleanup trailing chains.  Gaps may remain.
702                  */
703                 for (i = HAMMER2_MAXCLUSTER - 1; i >= 0; --i) {
704                         if (pmp->pfs_hmps[i])
705                                 break;
706                 }
707                 iroot->cluster.nchains = i + 1;
708
709                 /*
710                  * If the PMP has no elements remaining we can destroy it.
711                  * (this will transition management threads from frozen->exit).
712                  */
713                 if (iroot->cluster.nchains == 0) {
714                         kprintf("unmount hmp %p last ref to PMP=%p\n",
715                                 hmp, pmp);
716                         hammer2_pfsfree(pmp);
717                         goto again;
718                 }
719
720                 /*
721                  * If elements still remain we need to set the REMASTER
722                  * flag and unfreeze it.
723                  */
724                 if (didfreeze) {
725                         for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
726                                 if (pmp->pfs_hmps[i] == NULL)
727                                         continue;
728                                 hammer2_thr_remaster(&pmp->sync_thrs[i]);
729                                 hammer2_thr_unfreeze(&pmp->sync_thrs[i]);
730                                 for (j = 0; j < HAMMER2_XOPGROUPS; ++j) {
731                                         hammer2_thr_remaster(
732                                                 &pmp->xop_groups[j].thrs[i]);
733                                         hammer2_thr_unfreeze(
734                                                 &pmp->xop_groups[j].thrs[i]);
735                                 }
736                         }
737                 }
738         }
739 }
740
741 /*
742  * Mount or remount HAMMER2 fileystem from physical media
743  *
744  *      mountroot
745  *              mp              mount point structure
746  *              path            NULL
747  *              data            <unused>
748  *              cred            <unused>
749  *
750  *      mount
751  *              mp              mount point structure
752  *              path            path to mount point
753  *              data            pointer to argument structure in user space
754  *                      volume  volume path (device@LABEL form)
755  *                      hflags  user mount flags
756  *              cred            user credentials
757  *
758  * RETURNS:     0       Success
759  *              !0      error number
760  */
761 static
762 int
763 hammer2_vfs_mount(struct mount *mp, char *path, caddr_t data,
764                   struct ucred *cred)
765 {
766         struct hammer2_mount_info info;
767         hammer2_pfs_t *pmp;
768         hammer2_pfs_t *spmp;
769         hammer2_dev_t *hmp;
770         hammer2_dev_t *force_local;
771         hammer2_key_t key_next;
772         hammer2_key_t key_dummy;
773         hammer2_key_t lhc;
774         struct vnode *devvp;
775         struct nlookupdata nd;
776         hammer2_chain_t *parent;
777         hammer2_chain_t *chain;
778         hammer2_cluster_t *cluster;
779         const hammer2_inode_data_t *ripdata;
780         hammer2_blockref_t bref;
781         struct file *fp;
782         char devstr[MNAMELEN];
783         size_t size;
784         size_t done;
785         char *dev;
786         char *label;
787         int ronly = 1;
788         int error;
789         int cache_index;
790         int i;
791
792         hmp = NULL;
793         pmp = NULL;
794         dev = NULL;
795         label = NULL;
796         devvp = NULL;
797         cache_index = -1;
798
799         kprintf("hammer2_mount\n");
800
801         if (path == NULL) {
802                 /*
803                  * Root mount
804                  */
805                 bzero(&info, sizeof(info));
806                 info.cluster_fd = -1;
807                 ksnprintf(devstr, sizeof(devstr), "%s",
808                           mp->mnt_stat.f_mntfromname);
809                 kprintf("hammer2_mount: root '%s'\n", devstr);
810         } else {
811                 /*
812                  * Non-root mount or updating a mount
813                  */
814                 error = copyin(data, &info, sizeof(info));
815                 if (error)
816                         return (error);
817
818                 error = copyinstr(info.volume, devstr, MNAMELEN - 1, &done);
819                 if (error)
820                         return (error);
821         }
822
823         /* Extract device and label */
824         dev = devstr;
825         label = strchr(devstr, '@');
826         if (label == NULL ||
827             ((label + 1) - dev) > done) {
828                 return (EINVAL);
829         }
830         *label = '\0';
831         label++;
832         if (*label == '\0')
833                 return (EINVAL);
834
835         if (mp->mnt_flag & MNT_UPDATE) {
836                 /*
837                  * Update mount.  Note that pmp->iroot->cluster is
838                  * an inode-embedded cluster and thus cannot be
839                  * directly locked.
840                  *
841                  * XXX HAMMER2 needs to implement NFS export via
842                  *     mountctl.
843                  */
844                 pmp = MPTOPMP(mp);
845                 pmp->hflags = info.hflags;
846                 cluster = &pmp->iroot->cluster;
847                 for (i = 0; i < cluster->nchains; ++i) {
848                         if (cluster->array[i].chain == NULL)
849                                 continue;
850                         hmp = cluster->array[i].chain->hmp;
851                         devvp = hmp->devvp;
852                         error = hammer2_remount(hmp, mp, path,
853                                                 devvp, cred);
854                         if (error)
855                                 break;
856                 }
857
858                 return error;
859         }
860
861         /*
862          * HMP device mount
863          *
864          * Lookup name and verify it refers to a block device.
865          */
866         if (path) {
867                 error = nlookup_init(&nd, dev, UIO_SYSSPACE, NLC_FOLLOW);
868                 if (error == 0)
869                         error = nlookup(&nd);
870                 if (error == 0)
871                         error = cache_vref(&nd.nl_nch, nd.nl_cred, &devvp);
872                 nlookup_done(&nd);
873         } else {
874                 /* root mount */
875                 cdev_t cdev = kgetdiskbyname(dev);
876                 error = bdevvp(cdev, &devvp);
877                 if (error)
878                         kprintf("hammer2: cannot find '%s'\n", dev);
879         }
880
881         if (error == 0) {
882                 if (vn_isdisk(devvp, &error))
883                         error = vfs_mountedon(devvp);
884         }
885
886         /*
887          * Determine if the device has already been mounted.  After this
888          * check hmp will be non-NULL if we are doing the second or more
889          * hammer2 mounts from the same device.
890          */
891         lockmgr(&hammer2_mntlk, LK_EXCLUSIVE);
892         TAILQ_FOREACH(hmp, &hammer2_mntlist, mntentry) {
893                 if (hmp->devvp == devvp)
894                         break;
895         }
896
897         /*
898          * Open the device if this isn't a secondary mount and construct
899          * the H2 device mount (hmp).
900          */
901         if (hmp == NULL) {
902                 hammer2_chain_t *schain;
903                 hammer2_xid_t xid;
904
905                 if (error == 0 && vcount(devvp) > 0)
906                         error = EBUSY;
907
908                 /*
909                  * Now open the device
910                  */
911                 if (error == 0) {
912                         ronly = ((mp->mnt_flag & MNT_RDONLY) != 0);
913                         vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
914                         error = vinvalbuf(devvp, V_SAVE, 0, 0);
915                         if (error == 0) {
916                                 error = VOP_OPEN(devvp,
917                                                  ronly ? FREAD : FREAD | FWRITE,
918                                                  FSCRED, NULL);
919                         }
920                         vn_unlock(devvp);
921                 }
922                 if (error && devvp) {
923                         vrele(devvp);
924                         devvp = NULL;
925                 }
926                 if (error) {
927                         lockmgr(&hammer2_mntlk, LK_RELEASE);
928                         return error;
929                 }
930                 hmp = kmalloc(sizeof(*hmp), M_HAMMER2, M_WAITOK | M_ZERO);
931                 ksnprintf(hmp->devrepname, sizeof(hmp->devrepname), "%s", dev);
932                 hmp->ronly = ronly;
933                 hmp->devvp = devvp;
934                 hmp->hflags = info.hflags & HMNT2_DEVFLAGS;
935                 kmalloc_create(&hmp->mchain, "HAMMER2-chains");
936                 TAILQ_INSERT_TAIL(&hammer2_mntlist, hmp, mntentry);
937                 RB_INIT(&hmp->iotree);
938                 spin_init(&hmp->io_spin, "hm2mount_io");
939                 spin_init(&hmp->list_spin, "hm2mount_list");
940                 TAILQ_INIT(&hmp->flushq);
941
942                 lockinit(&hmp->vollk, "h2vol", 0, 0);
943                 lockinit(&hmp->bulklk, "h2bulk", 0, 0);
944
945                 /*
946                  * vchain setup. vchain.data is embedded.
947                  * vchain.refs is initialized and will never drop to 0.
948                  *
949                  * NOTE! voldata is not yet loaded.
950                  */
951                 hmp->vchain.hmp = hmp;
952                 hmp->vchain.refs = 1;
953                 hmp->vchain.data = (void *)&hmp->voldata;
954                 hmp->vchain.bref.type = HAMMER2_BREF_TYPE_VOLUME;
955                 hmp->vchain.bref.data_off = 0 | HAMMER2_PBUFRADIX;
956                 hmp->vchain.bref.mirror_tid = hmp->voldata.mirror_tid;
957
958                 hammer2_chain_core_init(&hmp->vchain);
959                 /* hmp->vchain.u.xxx is left NULL */
960
961                 /*
962                  * fchain setup.  fchain.data is embedded.
963                  * fchain.refs is initialized and will never drop to 0.
964                  *
965                  * The data is not used but needs to be initialized to
966                  * pass assertion muster.  We use this chain primarily
967                  * as a placeholder for the freemap's top-level RBTREE
968                  * so it does not interfere with the volume's topology
969                  * RBTREE.
970                  */
971                 hmp->fchain.hmp = hmp;
972                 hmp->fchain.refs = 1;
973                 hmp->fchain.data = (void *)&hmp->voldata.freemap_blockset;
974                 hmp->fchain.bref.type = HAMMER2_BREF_TYPE_FREEMAP;
975                 hmp->fchain.bref.data_off = 0 | HAMMER2_PBUFRADIX;
976                 hmp->fchain.bref.mirror_tid = hmp->voldata.freemap_tid;
977                 hmp->fchain.bref.methods =
978                         HAMMER2_ENC_CHECK(HAMMER2_CHECK_FREEMAP) |
979                         HAMMER2_ENC_COMP(HAMMER2_COMP_NONE);
980
981                 hammer2_chain_core_init(&hmp->fchain);
982                 /* hmp->fchain.u.xxx is left NULL */
983
984                 /*
985                  * Install the volume header and initialize fields from
986                  * voldata.
987                  */
988                 error = hammer2_install_volume_header(hmp);
989                 if (error) {
990                         hammer2_unmount_helper(mp, NULL, hmp);
991                         lockmgr(&hammer2_mntlk, LK_RELEASE);
992                         hammer2_vfs_unmount(mp, MNT_FORCE);
993                         return error;
994                 }
995
996                 /*
997                  * Really important to get these right or flush will get
998                  * confused.
999                  */
1000                 hmp->spmp = hammer2_pfsalloc(NULL, NULL, 0, NULL);
1001                 kprintf("alloc spmp %p tid %016jx\n",
1002                         hmp->spmp, hmp->voldata.mirror_tid);
1003                 spmp = hmp->spmp;
1004
1005                 /*
1006                  * Dummy-up vchain and fchain's modify_tid.  mirror_tid
1007                  * is inherited from the volume header.
1008                  */
1009                 xid = 0;
1010                 hmp->vchain.bref.mirror_tid = hmp->voldata.mirror_tid;
1011                 hmp->vchain.bref.modify_tid = hmp->vchain.bref.mirror_tid;
1012                 hmp->vchain.pmp = spmp;
1013                 hmp->fchain.bref.mirror_tid = hmp->voldata.freemap_tid;
1014                 hmp->fchain.bref.modify_tid = hmp->fchain.bref.mirror_tid;
1015                 hmp->fchain.pmp = spmp;
1016
1017                 /*
1018                  * First locate the super-root inode, which is key 0
1019                  * relative to the volume header's blockset.
1020                  *
1021                  * Then locate the root inode by scanning the directory keyspace
1022                  * represented by the label.
1023                  */
1024                 parent = hammer2_chain_lookup_init(&hmp->vchain, 0);
1025                 schain = hammer2_chain_lookup(&parent, &key_dummy,
1026                                       HAMMER2_SROOT_KEY, HAMMER2_SROOT_KEY,
1027                                       &cache_index, 0);
1028                 hammer2_chain_lookup_done(parent);
1029                 if (schain == NULL) {
1030                         kprintf("hammer2_mount: invalid super-root\n");
1031                         hammer2_unmount_helper(mp, NULL, hmp);
1032                         lockmgr(&hammer2_mntlk, LK_RELEASE);
1033                         hammer2_vfs_unmount(mp, MNT_FORCE);
1034                         return EINVAL;
1035                 }
1036                 if (schain->error) {
1037                         kprintf("hammer2_mount: error %s reading super-root\n",
1038                                 hammer2_error_str(schain->error));
1039                         hammer2_chain_unlock(schain);
1040                         hammer2_chain_drop(schain);
1041                         schain = NULL;
1042                         hammer2_unmount_helper(mp, NULL, hmp);
1043                         lockmgr(&hammer2_mntlk, LK_RELEASE);
1044                         hammer2_vfs_unmount(mp, MNT_FORCE);
1045                         return EINVAL;
1046                 }
1047
1048                 /*
1049                  * The super-root always uses an inode_tid of 1 when
1050                  * creating PFSs.
1051                  */
1052                 spmp->inode_tid = 1;
1053                 spmp->modify_tid = schain->bref.modify_tid + 1;
1054
1055                 /*
1056                  * Sanity-check schain's pmp and finish initialization.
1057                  * Any chain belonging to the super-root topology should
1058                  * have a NULL pmp (not even set to spmp).
1059                  */
1060                 ripdata = &hammer2_chain_rdata(schain)->ipdata;
1061                 KKASSERT(schain->pmp == NULL);
1062                 spmp->pfs_clid = ripdata->meta.pfs_clid;
1063
1064                 /*
1065                  * Replace the dummy spmp->iroot with a real one.  It's
1066                  * easier to just do a wholesale replacement than to try
1067                  * to update the chain and fixup the iroot fields.
1068                  *
1069                  * The returned inode is locked with the supplied cluster.
1070                  */
1071                 cluster = hammer2_cluster_from_chain(schain);
1072                 hammer2_inode_drop(spmp->iroot);
1073                 spmp->iroot = NULL;
1074                 spmp->iroot = hammer2_inode_get(spmp, NULL, cluster, -1);
1075                 spmp->spmp_hmp = hmp;
1076                 spmp->pfs_types[0] = ripdata->meta.pfs_type;
1077                 spmp->pfs_hmps[0] = hmp;
1078                 hammer2_inode_ref(spmp->iroot);
1079                 hammer2_inode_unlock(spmp->iroot);
1080                 hammer2_cluster_unlock(cluster);
1081                 hammer2_cluster_drop(cluster);
1082                 schain = NULL;
1083                 /* leave spmp->iroot with one ref */
1084
1085                 if ((mp->mnt_flag & MNT_RDONLY) == 0) {
1086                         error = hammer2_recovery(hmp);
1087                         /* XXX do something with error */
1088                 }
1089                 hammer2_update_pmps(hmp);
1090                 hammer2_iocom_init(hmp);
1091
1092                 /*
1093                  * Ref the cluster management messaging descriptor.  The mount
1094                  * program deals with the other end of the communications pipe.
1095                  *
1096                  * Root mounts typically do not supply one.
1097                  */
1098                 if (info.cluster_fd >= 0) {
1099                         fp = holdfp(curproc->p_fd, info.cluster_fd, -1);
1100                         if (fp) {
1101                                 hammer2_cluster_reconnect(hmp, fp);
1102                         } else {
1103                                 kprintf("hammer2_mount: bad cluster_fd!\n");
1104                         }
1105                 }
1106         } else {
1107                 spmp = hmp->spmp;
1108                 if (info.hflags & HMNT2_DEVFLAGS) {
1109                         kprintf("hammer2: Warning: mount flags pertaining "
1110                                 "to the whole device may only be specified "
1111                                 "on the first mount of the device: %08x\n",
1112                                 info.hflags & HMNT2_DEVFLAGS);
1113                 }
1114         }
1115
1116         /*
1117          * Force local mount (disassociate all PFSs from their clusters).
1118          * Used primarily for debugging.
1119          */
1120         force_local = (hmp->hflags & HMNT2_LOCAL) ? hmp : NULL;
1121
1122         /*
1123          * Lookup the mount point under the media-localized super-root.
1124          * Scanning hammer2_pfslist doesn't help us because it represents
1125          * PFS cluster ids which can aggregate several named PFSs together.
1126          *
1127          * cluster->pmp will incorrectly point to spmp and must be fixed
1128          * up later on.
1129          */
1130         hammer2_inode_lock(spmp->iroot, 0);
1131         parent = hammer2_inode_chain(spmp->iroot, 0, HAMMER2_RESOLVE_ALWAYS);
1132         lhc = hammer2_dirhash(label, strlen(label));
1133         chain = hammer2_chain_lookup(&parent, &key_next,
1134                                      lhc, lhc + HAMMER2_DIRHASH_LOMASK,
1135                                      &cache_index, 0);
1136         while (chain) {
1137                 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE &&
1138                     strcmp(label, chain->data->ipdata.filename) == 0) {
1139                         break;
1140                 }
1141                 chain = hammer2_chain_next(&parent, chain, &key_next,
1142                                             key_next,
1143                                             lhc + HAMMER2_DIRHASH_LOMASK,
1144                                             &cache_index, 0);
1145         }
1146         if (parent) {
1147                 hammer2_chain_unlock(parent);
1148                 hammer2_chain_drop(parent);
1149         }
1150         hammer2_inode_unlock(spmp->iroot);
1151
1152         /*
1153          * PFS could not be found?
1154          */
1155         if (chain == NULL) {
1156                 kprintf("hammer2_mount: PFS label not found\n");
1157                 hammer2_unmount_helper(mp, NULL, hmp);
1158                 lockmgr(&hammer2_mntlk, LK_RELEASE);
1159                 hammer2_vfs_unmount(mp, MNT_FORCE);
1160
1161                 return EINVAL;
1162         }
1163
1164         /*
1165          * Acquire the pmp structure (it should have already been allocated
1166          * via hammer2_update_pmps() so do not pass cluster in to add to
1167          * available chains).
1168          *
1169          * Check if the cluster has already been mounted.  A cluster can
1170          * only be mounted once, use null mounts to mount additional copies.
1171          */
1172         ripdata = &chain->data->ipdata;
1173         bref = chain->bref;
1174         pmp = hammer2_pfsalloc(NULL, ripdata, bref.modify_tid, force_local);
1175         hammer2_chain_unlock(chain);
1176         hammer2_chain_drop(chain);
1177
1178         if (pmp->mp) {
1179                 kprintf("hammer2_mount: PFS already mounted!\n");
1180                 hammer2_unmount_helper(mp, NULL, hmp);
1181                 lockmgr(&hammer2_mntlk, LK_RELEASE);
1182                 hammer2_vfs_unmount(mp, MNT_FORCE);
1183
1184                 return EBUSY;
1185         }
1186
1187         /*
1188          * Finish the mount
1189          */
1190         kprintf("hammer2_mount hmp=%p pmp=%p\n", hmp, pmp);
1191
1192         pmp->hflags = info.hflags;
1193         mp->mnt_flag = MNT_LOCAL;
1194         mp->mnt_kern_flag |= MNTK_ALL_MPSAFE;   /* all entry pts are SMP */
1195         mp->mnt_kern_flag |= MNTK_THR_SYNC;     /* new vsyncscan semantics */
1196  
1197         /*
1198          * required mount structure initializations
1199          */
1200         mp->mnt_stat.f_iosize = HAMMER2_PBUFSIZE;
1201         mp->mnt_stat.f_bsize = HAMMER2_PBUFSIZE;
1202  
1203         mp->mnt_vstat.f_frsize = HAMMER2_PBUFSIZE;
1204         mp->mnt_vstat.f_bsize = HAMMER2_PBUFSIZE;
1205  
1206         /*
1207          * Optional fields
1208          */
1209         mp->mnt_iosize_max = MAXPHYS;
1210
1211         /*
1212          * Connect up mount pointers.
1213          */
1214         hammer2_mount_helper(mp, pmp);
1215
1216         lockmgr(&hammer2_mntlk, LK_RELEASE);
1217
1218         /*
1219          * Finish setup
1220          */
1221         vfs_getnewfsid(mp);
1222         vfs_add_vnodeops(mp, &hammer2_vnode_vops, &mp->mnt_vn_norm_ops);
1223         vfs_add_vnodeops(mp, &hammer2_spec_vops, &mp->mnt_vn_spec_ops);
1224         vfs_add_vnodeops(mp, &hammer2_fifo_vops, &mp->mnt_vn_fifo_ops);
1225
1226         if (path) {
1227                 copyinstr(info.volume, mp->mnt_stat.f_mntfromname,
1228                           MNAMELEN - 1, &size);
1229                 bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
1230         } /* else root mount, already in there */
1231
1232         bzero(mp->mnt_stat.f_mntonname, sizeof(mp->mnt_stat.f_mntonname));
1233         if (path) {
1234                 copyinstr(path, mp->mnt_stat.f_mntonname,
1235                           sizeof(mp->mnt_stat.f_mntonname) - 1,
1236                           &size);
1237         } else {
1238                 /* root mount */
1239                 mp->mnt_stat.f_mntonname[0] = '/';
1240         }
1241
1242         /*
1243          * Initial statfs to prime mnt_stat.
1244          */
1245         hammer2_vfs_statfs(mp, &mp->mnt_stat, cred);
1246         
1247         return 0;
1248 }
1249
1250 /*
1251  * Scan PFSs under the super-root and create hammer2_pfs structures.
1252  */
1253 static
1254 void
1255 hammer2_update_pmps(hammer2_dev_t *hmp)
1256 {
1257         const hammer2_inode_data_t *ripdata;
1258         hammer2_chain_t *parent;
1259         hammer2_chain_t *chain;
1260         hammer2_blockref_t bref;
1261         hammer2_dev_t *force_local;
1262         hammer2_pfs_t *spmp;
1263         hammer2_pfs_t *pmp;
1264         hammer2_key_t key_next;
1265         int cache_index = -1;
1266
1267         /*
1268          * Force local mount (disassociate all PFSs from their clusters).
1269          * Used primarily for debugging.
1270          */
1271         force_local = (hmp->hflags & HMNT2_LOCAL) ? hmp : NULL;
1272
1273         /*
1274          * Lookup mount point under the media-localized super-root.
1275          *
1276          * cluster->pmp will incorrectly point to spmp and must be fixed
1277          * up later on.
1278          */
1279         spmp = hmp->spmp;
1280         hammer2_inode_lock(spmp->iroot, 0);
1281         parent = hammer2_inode_chain(spmp->iroot, 0, HAMMER2_RESOLVE_ALWAYS);
1282         chain = hammer2_chain_lookup(&parent, &key_next,
1283                                          HAMMER2_KEY_MIN, HAMMER2_KEY_MAX,
1284                                          &cache_index, 0);
1285         while (chain) {
1286                 if (chain->bref.type != HAMMER2_BREF_TYPE_INODE)
1287                         continue;
1288                 ripdata = &chain->data->ipdata;
1289                 bref = chain->bref;
1290                 kprintf("ADD LOCAL PFS: %s\n", ripdata->filename);
1291
1292                 pmp = hammer2_pfsalloc(chain, ripdata,
1293                                        bref.modify_tid, force_local);
1294                 chain = hammer2_chain_next(&parent, chain, &key_next,
1295                                            key_next, HAMMER2_KEY_MAX,
1296                                            &cache_index, 0);
1297         }
1298         if (parent) {
1299                 hammer2_chain_unlock(parent);
1300                 hammer2_chain_drop(parent);
1301         }
1302         hammer2_inode_unlock(spmp->iroot);
1303 }
1304
1305 static
1306 int
1307 hammer2_remount(hammer2_dev_t *hmp, struct mount *mp, char *path __unused,
1308                 struct vnode *devvp, struct ucred *cred)
1309 {
1310         int error;
1311
1312         if (hmp->ronly && (mp->mnt_kern_flag & MNTK_WANTRDWR)) {
1313                 error = hammer2_recovery(hmp);
1314         } else {
1315                 error = 0;
1316         }
1317         return error;
1318 }
1319
1320 static
1321 int
1322 hammer2_vfs_unmount(struct mount *mp, int mntflags)
1323 {
1324         hammer2_pfs_t *pmp;
1325         int flags;
1326         int error = 0;
1327
1328         pmp = MPTOPMP(mp);
1329
1330         if (pmp == NULL)
1331                 return(0);
1332
1333         lockmgr(&hammer2_mntlk, LK_EXCLUSIVE);
1334
1335         /*
1336          * If mount initialization proceeded far enough we must flush
1337          * its vnodes and sync the underlying mount points.  Three syncs
1338          * are required to fully flush the filesystem (freemap updates lag
1339          * by one flush, and one extra for safety).
1340          */
1341         if (mntflags & MNT_FORCE)
1342                 flags = FORCECLOSE;
1343         else
1344                 flags = 0;
1345         if (pmp->iroot) {
1346                 error = vflush(mp, 0, flags);
1347                 if (error)
1348                         goto failed;
1349                 hammer2_vfs_sync(mp, MNT_WAIT);
1350                 hammer2_vfs_sync(mp, MNT_WAIT);
1351                 hammer2_vfs_sync(mp, MNT_WAIT);
1352         }
1353
1354         /*
1355          * Cleanup the frontend support XOPS threads
1356          */
1357         hammer2_xop_helper_cleanup(pmp);
1358
1359         if (pmp->mp)
1360                 hammer2_unmount_helper(mp, pmp, NULL);
1361
1362         error = 0;
1363 failed:
1364         lockmgr(&hammer2_mntlk, LK_RELEASE);
1365
1366         return (error);
1367 }
1368
1369 /*
1370  * Mount helper, hook the system mount into our PFS.
1371  * The mount lock is held.
1372  *
1373  * We must bump the mount_count on related devices for any
1374  * mounted PFSs.
1375  */
1376 static
1377 void
1378 hammer2_mount_helper(struct mount *mp, hammer2_pfs_t *pmp)
1379 {
1380         hammer2_cluster_t *cluster;
1381         hammer2_chain_t *rchain;
1382         int i;
1383
1384         mp->mnt_data = (qaddr_t)pmp;
1385         pmp->mp = mp;
1386
1387         /*
1388          * After pmp->mp is set we have to adjust hmp->mount_count.
1389          */
1390         cluster = &pmp->iroot->cluster;
1391         for (i = 0; i < cluster->nchains; ++i) {
1392                 rchain = cluster->array[i].chain;
1393                 if (rchain == NULL)
1394                         continue;
1395                 ++rchain->hmp->mount_count;
1396                 kprintf("hammer2_mount hmp=%p ++mount_count=%d\n",
1397                         rchain->hmp, rchain->hmp->mount_count);
1398         }
1399
1400         /*
1401          * Create missing Xop threads
1402          */
1403         hammer2_xop_helper_create(pmp);
1404 }
1405
1406 /*
1407  * Mount helper, unhook the system mount from our PFS.
1408  * The mount lock is held.
1409  *
1410  * If hmp is supplied a mount responsible for being the first to open
1411  * the block device failed and the block device and all PFSs using the
1412  * block device must be cleaned up.
1413  *
1414  * If pmp is supplied multiple devices might be backing the PFS and each
1415  * must be disconnected.  This might not be the last PFS using some of the
1416  * underlying devices.  Also, we have to adjust our hmp->mount_count
1417  * accounting for the devices backing the pmp which is now undergoing an
1418  * unmount.
1419  */
1420 static
1421 void
1422 hammer2_unmount_helper(struct mount *mp, hammer2_pfs_t *pmp, hammer2_dev_t *hmp)
1423 {
1424         hammer2_cluster_t *cluster;
1425         hammer2_chain_t *rchain;
1426         struct vnode *devvp;
1427         int dumpcnt;
1428         int ronly = 0;
1429         int i;
1430
1431         /*
1432          * If no device supplied this is a high-level unmount and we have to
1433          * to disconnect the mount, adjust mount_count, and locate devices
1434          * that might now have no mounts.
1435          */
1436         if (pmp) {
1437                 KKASSERT(hmp == NULL);
1438                 KKASSERT((void *)(intptr_t)mp->mnt_data == pmp);
1439                 pmp->mp = NULL;
1440                 mp->mnt_data = NULL;
1441
1442                 /*
1443                  * After pmp->mp is cleared we have to account for
1444                  * mount_count.
1445                  */
1446                 cluster = &pmp->iroot->cluster;
1447                 for (i = 0; i < cluster->nchains; ++i) {
1448                         rchain = cluster->array[i].chain;
1449                         if (rchain == NULL)
1450                                 continue;
1451                         --rchain->hmp->mount_count;
1452                         kprintf("hammer2_unmount hmp=%p --mount_count=%d\n",
1453                                 rchain->hmp, rchain->hmp->mount_count);
1454                         /* scrapping hmp now may invalidate the pmp */
1455                 }
1456 again:
1457                 TAILQ_FOREACH(hmp, &hammer2_mntlist, mntentry) {
1458                         if (hmp->mount_count == 0) {
1459                                 hammer2_unmount_helper(NULL, NULL, hmp);
1460                                 goto again;
1461                         }
1462                 }
1463                 return;
1464         }
1465
1466         /*
1467          * Try to terminate the block device.  We can't terminate it if
1468          * there are still PFSs referencing it.
1469          */
1470         kprintf("hammer2_unmount hmp=%p mount_count=%d\n",
1471                 hmp, hmp->mount_count);
1472         if (hmp->mount_count)
1473                 return;
1474
1475         hammer2_pfsfree_scan(hmp);
1476         hammer2_dev_exlock(hmp);        /* XXX order */
1477
1478         /*
1479          * Cycle the volume data lock as a safety (probably not needed any
1480          * more).  To ensure everything is out we need to flush at least
1481          * three times.  (1) The running of the sideq can dirty the
1482          * filesystem, (2) A normal flush can dirty the freemap, and
1483          * (3) ensure that the freemap is fully synchronized.
1484          *
1485          * The next mount's recovery scan can clean everything up but we want
1486          * to leave the filesystem in a 100% clean state on a normal unmount.
1487          */
1488 #if 0
1489         hammer2_voldata_lock(hmp);
1490         hammer2_voldata_unlock(hmp);
1491 #endif
1492         hammer2_iocom_uninit(hmp);
1493
1494         if ((hmp->vchain.flags | hmp->fchain.flags) &
1495             HAMMER2_CHAIN_FLUSH_MASK) {
1496                 kprintf("hammer2_unmount: chains left over "
1497                         "after final sync\n");
1498                 kprintf("    vchain %08x\n", hmp->vchain.flags);
1499                 kprintf("    fchain %08x\n", hmp->fchain.flags);
1500
1501                 if (hammer2_debug & 0x0010)
1502                         Debugger("entered debugger");
1503         }
1504
1505         KKASSERT(hmp->spmp == NULL);
1506
1507         /*
1508          * Finish up with the device vnode
1509          */
1510         if ((devvp = hmp->devvp) != NULL) {
1511                 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
1512                 vinvalbuf(devvp, (ronly ? 0 : V_SAVE), 0, 0);
1513                 hmp->devvp = NULL;
1514                 VOP_CLOSE(devvp, (ronly ? FREAD : FREAD|FWRITE), NULL);
1515                 vn_unlock(devvp);
1516                 vrele(devvp);
1517                 devvp = NULL;
1518         }
1519
1520         /*
1521          * Clear vchain/fchain flags that might prevent final cleanup
1522          * of these chains.
1523          */
1524         if (hmp->vchain.flags & HAMMER2_CHAIN_MODIFIED) {
1525                 atomic_add_long(&hammer2_count_modified_chains, -1);
1526                 atomic_clear_int(&hmp->vchain.flags, HAMMER2_CHAIN_MODIFIED);
1527                 hammer2_pfs_memory_wakeup(hmp->vchain.pmp);
1528         }
1529         if (hmp->vchain.flags & HAMMER2_CHAIN_UPDATE) {
1530                 atomic_clear_int(&hmp->vchain.flags, HAMMER2_CHAIN_UPDATE);
1531         }
1532
1533         if (hmp->fchain.flags & HAMMER2_CHAIN_MODIFIED) {
1534                 atomic_add_long(&hammer2_count_modified_chains, -1);
1535                 atomic_clear_int(&hmp->fchain.flags, HAMMER2_CHAIN_MODIFIED);
1536                 hammer2_pfs_memory_wakeup(hmp->fchain.pmp);
1537         }
1538         if (hmp->fchain.flags & HAMMER2_CHAIN_UPDATE) {
1539                 atomic_clear_int(&hmp->fchain.flags, HAMMER2_CHAIN_UPDATE);
1540         }
1541
1542         /*
1543          * Final drop of embedded freemap root chain to
1544          * clean up fchain.core (fchain structure is not
1545          * flagged ALLOCATED so it is cleaned out and then
1546          * left to rot).
1547          */
1548         hammer2_chain_drop(&hmp->fchain);
1549
1550         /*
1551          * Final drop of embedded volume root chain to clean
1552          * up vchain.core (vchain structure is not flagged
1553          * ALLOCATED so it is cleaned out and then left to
1554          * rot).
1555          */
1556         dumpcnt = 50;
1557         hammer2_dump_chain(&hmp->vchain, 0, &dumpcnt, 'v');
1558         dumpcnt = 50;
1559         hammer2_dump_chain(&hmp->fchain, 0, &dumpcnt, 'f');
1560         hammer2_dev_unlock(hmp);
1561         hammer2_chain_drop(&hmp->vchain);
1562
1563         hammer2_io_cleanup(hmp, &hmp->iotree);
1564         if (hmp->iofree_count) {
1565                 kprintf("io_cleanup: %d I/O's left hanging\n",
1566                         hmp->iofree_count);
1567         }
1568
1569         TAILQ_REMOVE(&hammer2_mntlist, hmp, mntentry);
1570         kmalloc_destroy(&hmp->mchain);
1571         kfree(hmp, M_HAMMER2);
1572 }
1573
1574 int
1575 hammer2_vfs_vget(struct mount *mp, struct vnode *dvp,
1576                  ino_t ino, struct vnode **vpp)
1577 {
1578         hammer2_xop_lookup_t *xop;
1579         hammer2_pfs_t *pmp;
1580         hammer2_inode_t *ip;
1581         hammer2_tid_t inum;
1582         int error;
1583
1584         inum = (hammer2_tid_t)ino & HAMMER2_DIRHASH_USERMSK;
1585
1586         error = 0;
1587         pmp = MPTOPMP(mp);
1588
1589         /*
1590          * Easy if we already have it cached
1591          */
1592         ip = hammer2_inode_lookup(pmp, inum);
1593         if (ip) {
1594                 hammer2_inode_lock(ip, HAMMER2_RESOLVE_SHARED);
1595                 *vpp = hammer2_igetv(ip, &error);
1596                 hammer2_inode_unlock(ip);
1597                 hammer2_inode_drop(ip);         /* from lookup */
1598
1599                 return error;
1600         }
1601
1602         /*
1603          * Otherwise we have to find the inode
1604          */
1605         xop = hammer2_xop_alloc(pmp->iroot, 0);
1606         xop->lhc = inum;
1607         hammer2_xop_start(&xop->head, hammer2_xop_lookup);
1608         error = hammer2_xop_collect(&xop->head, 0);
1609
1610         if (error == 0) {
1611                 if (hammer2_cluster_rdata(&xop->head.cluster) == NULL) {
1612                         kprintf("vget: no collect error but also no rdata\n");
1613                         kprintf("xop %p\n", xop);
1614                         while ((hammer2_debug & 0x80000) == 0) {
1615                                 tsleep(xop, PCATCH, "wait", hz * 10);
1616                         }
1617                         ip = NULL;
1618                 } else {
1619                         ip = hammer2_inode_get(pmp, NULL, &xop->head.cluster, -1);
1620                 }
1621         }
1622         hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP);
1623
1624         if (ip) {
1625                 *vpp = hammer2_igetv(ip, &error);
1626                 hammer2_inode_unlock(ip);
1627         } else {
1628                 *vpp = NULL;
1629                 error = ENOENT;
1630         }
1631         return (error);
1632 }
1633
1634 static
1635 int
1636 hammer2_vfs_root(struct mount *mp, struct vnode **vpp)
1637 {
1638         hammer2_pfs_t *pmp;
1639         struct vnode *vp;
1640         int error;
1641
1642         pmp = MPTOPMP(mp);
1643         if (pmp->iroot == NULL) {
1644                 *vpp = NULL;
1645                 return EINVAL;
1646         }
1647
1648         error = 0;
1649         hammer2_inode_lock(pmp->iroot, HAMMER2_RESOLVE_SHARED);
1650
1651         while (pmp->inode_tid == 0) {
1652                 hammer2_xop_ipcluster_t *xop;
1653                 hammer2_inode_meta_t *meta;
1654
1655                 xop = hammer2_xop_alloc(pmp->iroot, HAMMER2_XOP_MODIFYING);
1656                 hammer2_xop_start(&xop->head, hammer2_xop_ipcluster);
1657                 error = hammer2_xop_collect(&xop->head, 0);
1658
1659                 if (error == 0) {
1660                         meta = &xop->head.cluster.focus->data->ipdata.meta;
1661                         pmp->iroot->meta = *meta;
1662                         pmp->inode_tid = meta->pfs_inum + 1;
1663                         if (pmp->inode_tid < HAMMER2_INODE_START)
1664                                 pmp->inode_tid = HAMMER2_INODE_START;
1665                         pmp->modify_tid =
1666                                 xop->head.cluster.focus->bref.modify_tid + 1;
1667                         kprintf("PFS: Starting inode %jd\n",
1668                                 (intmax_t)pmp->inode_tid);
1669                         kprintf("PMP focus good set nextino=%ld mod=%016jx\n",
1670                                 pmp->inode_tid, pmp->modify_tid);
1671                         wakeup(&pmp->iroot);
1672
1673                         hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP);
1674
1675                         /*
1676                          * Prime the mount info.
1677                          */
1678                         hammer2_vfs_statfs(mp, &mp->mnt_stat, NULL);
1679                         break;
1680                 }
1681
1682                 /*
1683                  * Loop, try again
1684                  */
1685                 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP);
1686                 hammer2_inode_unlock(pmp->iroot);
1687                 error = tsleep(&pmp->iroot, PCATCH, "h2root", hz);
1688                 hammer2_inode_lock(pmp->iroot, HAMMER2_RESOLVE_SHARED);
1689                 if (error == EINTR)
1690                         break;
1691         }
1692
1693         if (error) {
1694                 hammer2_inode_unlock(pmp->iroot);
1695                 *vpp = NULL;
1696         } else {
1697                 vp = hammer2_igetv(pmp->iroot, &error);
1698                 hammer2_inode_unlock(pmp->iroot);
1699                 *vpp = vp;
1700         }
1701
1702         return (error);
1703 }
1704
1705 /*
1706  * Filesystem status
1707  *
1708  * XXX incorporate ipdata->meta.inode_quota and data_quota
1709  */
1710 static
1711 int
1712 hammer2_vfs_statfs(struct mount *mp, struct statfs *sbp, struct ucred *cred)
1713 {
1714         hammer2_pfs_t *pmp;
1715         hammer2_dev_t *hmp;
1716         hammer2_blockref_t bref;
1717         int i;
1718
1719         /*
1720          * NOTE: iroot might not have validated the cluster yet.
1721          */
1722         pmp = MPTOPMP(mp);
1723
1724         mp->mnt_stat.f_files = 0;
1725         mp->mnt_stat.f_ffree = 0;
1726         mp->mnt_stat.f_blocks = 0;
1727         mp->mnt_stat.f_bfree = 0;
1728         mp->mnt_stat.f_bavail = 0;
1729
1730         for (i = 0; i < pmp->iroot->cluster.nchains; ++i) {
1731                 hmp = pmp->pfs_hmps[i];
1732                 if (hmp == NULL)
1733                         continue;
1734                 if (pmp->iroot->cluster.array[i].chain)
1735                         bref = pmp->iroot->cluster.array[i].chain->bref;
1736                 else
1737                         bzero(&bref, sizeof(bref));
1738
1739                 mp->mnt_stat.f_files = bref.inode_count;
1740                 mp->mnt_stat.f_ffree = 0;
1741 #if 0
1742                 mp->mnt_stat.f_blocks = (bref.data_count +
1743                                          hmp->voldata.allocator_free) /
1744                                         mp->mnt_vstat.f_bsize;
1745                 mp->mnt_stat.f_bfree =  hmp->voldata.allocator_free /
1746                                         mp->mnt_vstat.f_bsize;
1747 #endif
1748                 mp->mnt_stat.f_blocks = hmp->voldata.allocator_size /
1749                                         mp->mnt_vstat.f_bsize;
1750                 mp->mnt_stat.f_bfree = hmp->voldata.allocator_free /
1751                                         mp->mnt_vstat.f_bsize;
1752                 mp->mnt_stat.f_bavail = mp->mnt_stat.f_bfree;
1753
1754                 *sbp = mp->mnt_stat;
1755         }
1756         return (0);
1757 }
1758
1759 static
1760 int
1761 hammer2_vfs_statvfs(struct mount *mp, struct statvfs *sbp, struct ucred *cred)
1762 {
1763         hammer2_pfs_t *pmp;
1764         hammer2_dev_t *hmp;
1765         hammer2_blockref_t bref;
1766         int i;
1767
1768         /*
1769          * NOTE: iroot might not have validated the cluster yet.
1770          */
1771         pmp = MPTOPMP(mp);
1772
1773         mp->mnt_vstat.f_bsize = 0;
1774         mp->mnt_vstat.f_files = 0;
1775         mp->mnt_vstat.f_ffree = 0;
1776         mp->mnt_vstat.f_blocks = 0;
1777         mp->mnt_vstat.f_bfree = 0;
1778         mp->mnt_vstat.f_bavail = 0;
1779
1780         for (i = 0; i < pmp->iroot->cluster.nchains; ++i) {
1781                 hmp = pmp->pfs_hmps[i];
1782                 if (hmp == NULL)
1783                         continue;
1784                 if (pmp->iroot->cluster.array[i].chain)
1785                         bref = pmp->iroot->cluster.array[i].chain->bref;
1786                 else
1787                         bzero(&bref, sizeof(bref));
1788
1789                 mp->mnt_vstat.f_bsize = HAMMER2_PBUFSIZE;
1790                 mp->mnt_vstat.f_files = bref.inode_count;
1791                 mp->mnt_vstat.f_ffree = 0;
1792 #if 0
1793                 mp->mnt_vstat.f_blocks = (bref.data_count +
1794                                          hmp->voldata.allocator_free) /
1795                                         mp->mnt_vstat.f_bsize;
1796                 mp->mnt_vstat.f_bfree = hmp->voldata.allocator_free /
1797                                         mp->mnt_vstat.f_bsize;
1798 #endif
1799                 mp->mnt_vstat.f_blocks = hmp->voldata.allocator_size /
1800                                         mp->mnt_vstat.f_bsize;
1801                 mp->mnt_vstat.f_bfree = hmp->voldata.allocator_free /
1802                                         mp->mnt_vstat.f_bsize;
1803                 mp->mnt_vstat.f_bavail = mp->mnt_vstat.f_bfree;
1804
1805                 *sbp = mp->mnt_vstat;
1806         }
1807         return (0);
1808 }
1809
1810 /*
1811  * Mount-time recovery (RW mounts)
1812  *
1813  * Updates to the free block table are allowed to lag flushes by one
1814  * transaction.  In case of a crash, then on a fresh mount we must do an
1815  * incremental scan of the last committed transaction id and make sure that
1816  * all related blocks have been marked allocated.
1817  *
1818  * The super-root topology and each PFS has its own transaction id domain,
1819  * so we must track PFS boundary transitions.
1820  */
1821 struct hammer2_recovery_elm {
1822         TAILQ_ENTRY(hammer2_recovery_elm) entry;
1823         hammer2_chain_t *chain;
1824         hammer2_tid_t sync_tid;
1825 };
1826
1827 TAILQ_HEAD(hammer2_recovery_list, hammer2_recovery_elm);
1828
1829 struct hammer2_recovery_info {
1830         struct hammer2_recovery_list list;
1831         hammer2_tid_t   mtid;
1832         int     depth;
1833 };
1834
1835 static int hammer2_recovery_scan(hammer2_dev_t *hmp,
1836                         hammer2_chain_t *parent,
1837                         struct hammer2_recovery_info *info,
1838                         hammer2_tid_t sync_tid);
1839
1840 #define HAMMER2_RECOVERY_MAXDEPTH       10
1841
1842 static
1843 int
1844 hammer2_recovery(hammer2_dev_t *hmp)
1845 {
1846         struct hammer2_recovery_info info;
1847         struct hammer2_recovery_elm *elm;
1848         hammer2_chain_t *parent;
1849         hammer2_tid_t sync_tid;
1850         hammer2_tid_t mirror_tid;
1851         int error;
1852         int cumulative_error = 0;
1853
1854         hammer2_trans_init(hmp->spmp, 0);
1855
1856         sync_tid = hmp->voldata.freemap_tid;
1857         mirror_tid = hmp->voldata.mirror_tid;
1858
1859         kprintf("hammer2 mount \"%s\": ", hmp->devrepname);
1860         if (sync_tid >= mirror_tid) {
1861                 kprintf(" no recovery needed\n");
1862         } else {
1863                 kprintf(" freemap recovery %016jx-%016jx\n",
1864                         sync_tid + 1, mirror_tid);
1865         }
1866
1867         TAILQ_INIT(&info.list);
1868         info.depth = 0;
1869         parent = hammer2_chain_lookup_init(&hmp->vchain, 0);
1870         cumulative_error = hammer2_recovery_scan(hmp, parent, &info, sync_tid);
1871         hammer2_chain_lookup_done(parent);
1872
1873         while ((elm = TAILQ_FIRST(&info.list)) != NULL) {
1874                 TAILQ_REMOVE(&info.list, elm, entry);
1875                 parent = elm->chain;
1876                 sync_tid = elm->sync_tid;
1877                 kfree(elm, M_HAMMER2);
1878
1879                 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
1880                 error = hammer2_recovery_scan(hmp, parent, &info,
1881                                               hmp->voldata.freemap_tid);
1882                 hammer2_chain_unlock(parent);
1883                 hammer2_chain_drop(parent);     /* drop elm->chain ref */
1884                 if (error)
1885                         cumulative_error = error;
1886         }
1887         hammer2_trans_done(hmp->spmp);
1888
1889         return cumulative_error;
1890 }
1891
1892 static
1893 int
1894 hammer2_recovery_scan(hammer2_dev_t *hmp, hammer2_chain_t *parent,
1895                       struct hammer2_recovery_info *info,
1896                       hammer2_tid_t sync_tid)
1897 {
1898         const hammer2_inode_data_t *ripdata;
1899         hammer2_chain_t *chain;
1900         hammer2_blockref_t bref;
1901         int cache_index;
1902         int cumulative_error = 0;
1903         int error;
1904         int first;
1905
1906         /*
1907          * Adjust freemap to ensure that the block(s) are marked allocated.
1908          */
1909         if (parent->bref.type != HAMMER2_BREF_TYPE_VOLUME) {
1910                 hammer2_freemap_adjust(hmp, &parent->bref,
1911                                        HAMMER2_FREEMAP_DORECOVER);
1912         }
1913
1914         /*
1915          * Check type for recursive scan
1916          */
1917         switch(parent->bref.type) {
1918         case HAMMER2_BREF_TYPE_VOLUME:
1919                 /* data already instantiated */
1920                 break;
1921         case HAMMER2_BREF_TYPE_INODE:
1922                 /*
1923                  * Must instantiate data for DIRECTDATA test and also
1924                  * for recursion.
1925                  */
1926                 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
1927                 ripdata = &hammer2_chain_rdata(parent)->ipdata;
1928                 if (ripdata->meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA) {
1929                         /* not applicable to recovery scan */
1930                         hammer2_chain_unlock(parent);
1931                         return 0;
1932                 }
1933                 hammer2_chain_unlock(parent);
1934                 break;
1935         case HAMMER2_BREF_TYPE_INDIRECT:
1936                 /*
1937                  * Must instantiate data for recursion
1938                  */
1939                 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
1940                 hammer2_chain_unlock(parent);
1941                 break;
1942         case HAMMER2_BREF_TYPE_DATA:
1943         case HAMMER2_BREF_TYPE_FREEMAP:
1944         case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1945         case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
1946                 /* not applicable to recovery scan */
1947                 return 0;
1948                 break;
1949         default:
1950                 return EDOM;
1951         }
1952
1953         /*
1954          * Defer operation if depth limit reached or if we are crossing a
1955          * PFS boundary.
1956          */
1957         if (info->depth >= HAMMER2_RECOVERY_MAXDEPTH) {
1958                 struct hammer2_recovery_elm *elm;
1959
1960                 elm = kmalloc(sizeof(*elm), M_HAMMER2, M_ZERO | M_WAITOK);
1961                 elm->chain = parent;
1962                 elm->sync_tid = sync_tid;
1963                 hammer2_chain_ref(parent);
1964                 TAILQ_INSERT_TAIL(&info->list, elm, entry);
1965                 /* unlocked by caller */
1966
1967                 return(0);
1968         }
1969
1970
1971         /*
1972          * Recursive scan of the last flushed transaction only.  We are
1973          * doing this without pmp assignments so don't leave the chains
1974          * hanging around after we are done with them.
1975          */
1976         cache_index = 0;
1977         chain = NULL;
1978         first = 1;
1979
1980         while (hammer2_chain_scan(parent, &chain, &bref,
1981                                   &first, &cache_index,
1982                                   HAMMER2_LOOKUP_NODATA) != NULL) {
1983                 /*
1984                  * If this is a leaf
1985                  */
1986                 if (chain == NULL) {
1987                         if (bref.mirror_tid > sync_tid) {
1988                                 hammer2_freemap_adjust(hmp, &bref,
1989                                                      HAMMER2_FREEMAP_DORECOVER);
1990                         }
1991                         continue;
1992                 }
1993
1994                 /*
1995                  * This may or may not be a recursive node.
1996                  */
1997                 atomic_set_int(&chain->flags, HAMMER2_CHAIN_RELEASE);
1998                 if (bref.mirror_tid > sync_tid) {
1999                         ++info->depth;
2000                         error = hammer2_recovery_scan(hmp, chain,
2001                                                       info, sync_tid);
2002                         --info->depth;
2003                         if (error)
2004                                 cumulative_error = error;
2005                 }
2006
2007                 /*
2008                  * Flush the recovery at the PFS boundary to stage it for
2009                  * the final flush of the super-root topology.
2010                  */
2011                 if ((bref.flags & HAMMER2_BREF_FLAG_PFSROOT) &&
2012                     (chain->flags & HAMMER2_CHAIN_ONFLUSH)) {
2013                         hammer2_flush(chain, HAMMER2_FLUSH_TOP);
2014                 }
2015         }
2016
2017         return cumulative_error;
2018 }
2019
2020 /*
2021  * Sync a mount point; this is called on a per-mount basis from the
2022  * filesystem syncer process periodically and whenever a user issues
2023  * a sync.
2024  */
2025 int
2026 hammer2_vfs_sync(struct mount *mp, int waitfor)
2027 {
2028         hammer2_xop_flush_t *xop;
2029         struct hammer2_sync_info info;
2030         hammer2_inode_t *iroot;
2031         hammer2_pfs_t *pmp;
2032         int flags;
2033         int error;
2034
2035         pmp = MPTOPMP(mp);
2036         iroot = pmp->iroot;
2037         KKASSERT(iroot);
2038         KKASSERT(iroot->pmp == pmp);
2039
2040         /*
2041          * We can't acquire locks on existing vnodes while in a transaction
2042          * without risking a deadlock.  This assumes that vfsync() can be
2043          * called without the vnode locked (which it can in DragonFly).
2044          * Otherwise we'd have to implement a multi-pass or flag the lock
2045          * failures and retry.
2046          *
2047          * The reclamation code interlocks with the sync list's token
2048          * (by removing the vnode from the scan list) before unlocking
2049          * the inode, giving us time to ref the inode.
2050          */
2051         /*flags = VMSC_GETVP;*/
2052         flags = 0;
2053         if (waitfor & MNT_LAZY)
2054                 flags |= VMSC_ONEPASS;
2055
2056 #if 1
2057         /*
2058          * Preflush the vnodes using a normal transaction before interlocking
2059          * with a flush transaction.  We do this to try to run as much of
2060          * the compression as possible outside the flush transaction.
2061          */
2062         hammer2_trans_init(pmp, 0);
2063         info.error = 0;
2064         info.waitfor = MNT_NOWAIT;
2065         vsyncscan(mp, flags | VMSC_NOWAIT, hammer2_sync_scan2, &info);
2066         hammer2_trans_done(pmp);
2067 #endif
2068
2069         /*
2070          * Start our flush transaction.  This does not return until all
2071          * concurrent transactions have completed and will prevent any
2072          * new transactions from running concurrently, except for the
2073          * buffer cache transactions.
2074          *
2075          * For efficiency do an async pass before making sure with a
2076          * synchronous pass on all related buffer cache buffers.  It
2077          * should theoretically not be possible for any new file buffers
2078          * to be instantiated during this sequence.
2079          */
2080         hammer2_trans_init(pmp, HAMMER2_TRANS_ISFLUSH |
2081                                 HAMMER2_TRANS_PREFLUSH);
2082         hammer2_inode_run_sideq(pmp);
2083
2084         info.error = 0;
2085         info.waitfor = MNT_NOWAIT;
2086         vsyncscan(mp, flags | VMSC_NOWAIT, hammer2_sync_scan2, &info);
2087         info.waitfor = MNT_WAIT;
2088         vsyncscan(mp, flags, hammer2_sync_scan2, &info);
2089
2090         /*
2091          * Clear PREFLUSH.  This prevents (or asserts on) any new logical
2092          * buffer cache flushes which occur during the flush.  Device buffers
2093          * are not affected.
2094          */
2095         hammer2_bioq_sync(pmp);
2096         hammer2_trans_clear_preflush(pmp);
2097
2098         /*
2099          * Use the XOP interface to concurrently flush all nodes to
2100          * synchronize the PFSROOT subtopology to the media.  A standard
2101          * end-of-scan ENOENT error indicates cluster sufficiency.
2102          *
2103          * Note that this flush will not be visible on crash recovery until
2104          * we flush the super-root topology in the next loop.
2105          *
2106          * XXX For now wait for all flushes to complete.
2107          */
2108         if (iroot) {
2109                 xop = hammer2_xop_alloc(iroot, HAMMER2_XOP_MODIFYING);
2110                 hammer2_xop_start(&xop->head, hammer2_inode_xop_flush);
2111                 error = hammer2_xop_collect(&xop->head,
2112                                             HAMMER2_XOP_COLLECT_WAITALL);
2113                 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP);
2114                 if (error == ENOENT)
2115                         error = 0;
2116         } else {
2117                 error = 0;
2118         }
2119         hammer2_trans_done(pmp);
2120
2121         return (error);
2122 }
2123
2124 /*
2125  * Sync passes.
2126  *
2127  * Note that we ignore the tranasction mtid we got above.  Instead,
2128  * each vfsync below will ultimately get its own via TRANS_BUFCACHE
2129  * transactions.
2130  */
2131 static int
2132 hammer2_sync_scan2(struct mount *mp, struct vnode *vp, void *data)
2133 {
2134         struct hammer2_sync_info *info = data;
2135         hammer2_inode_t *ip;
2136         int error;
2137
2138         /*
2139          * Degenerate cases.  Note that ip == NULL typically means the
2140          * syncer vnode itself and we don't want to vclrisdirty() in that
2141          * situation.
2142          */
2143         ip = VTOI(vp);
2144         if (ip == NULL) {
2145                 return(0);
2146         }
2147         if (vp->v_type == VNON || vp->v_type == VBAD) {
2148                 vclrisdirty(vp);
2149                 return(0);
2150         }
2151
2152         /*
2153          * VOP_FSYNC will start a new transaction so replicate some code
2154          * here to do it inline (see hammer2_vop_fsync()).
2155          *
2156          * WARNING: The vfsync interacts with the buffer cache and might
2157          *          block, we can't hold the inode lock at that time.
2158          *          However, we MUST ref ip before blocking to ensure that
2159          *          it isn't ripped out from under us (since we do not
2160          *          hold a lock on the vnode).
2161          */
2162         hammer2_inode_ref(ip);
2163         if ((ip->flags & HAMMER2_INODE_MODIFIED) ||
2164             !RB_EMPTY(&vp->v_rbdirty_tree)) {
2165                 vfsync(vp, info->waitfor, 1, NULL, NULL);
2166                 if (ip->flags & (HAMMER2_INODE_RESIZED |
2167                                  HAMMER2_INODE_MODIFIED)) {
2168                         hammer2_inode_lock(ip, 0);
2169                         hammer2_inode_chain_sync(ip);
2170                         hammer2_inode_unlock(ip);
2171                 }
2172         }
2173         if ((ip->flags & HAMMER2_INODE_MODIFIED) == 0 &&
2174             RB_EMPTY(&vp->v_rbdirty_tree)) {
2175                 vclrisdirty(vp);
2176         }
2177
2178         hammer2_inode_drop(ip);
2179 #if 1
2180         error = 0;
2181         if (error)
2182                 info->error = error;
2183 #endif
2184         return(0);
2185 }
2186
2187 static
2188 int
2189 hammer2_vfs_vptofh(struct vnode *vp, struct fid *fhp)
2190 {
2191         hammer2_inode_t *ip;
2192
2193         KKASSERT(MAXFIDSZ >= 16);
2194         ip = VTOI(vp);
2195         fhp->fid_len = offsetof(struct fid, fid_data[16]);
2196         fhp->fid_ext = 0;
2197         ((hammer2_tid_t *)fhp->fid_data)[0] = ip->meta.inum;
2198         ((hammer2_tid_t *)fhp->fid_data)[1] = 0;
2199
2200         return 0;
2201 }
2202
2203 static
2204 int
2205 hammer2_vfs_fhtovp(struct mount *mp, struct vnode *rootvp,
2206                struct fid *fhp, struct vnode **vpp)
2207 {
2208         hammer2_pfs_t *pmp;
2209         hammer2_tid_t inum;
2210         int error;
2211
2212         pmp = MPTOPMP(mp);
2213         inum = ((hammer2_tid_t *)fhp->fid_data)[0] & HAMMER2_DIRHASH_USERMSK;
2214         if (vpp) {
2215                 if (inum == 1)
2216                         error = hammer2_vfs_root(mp, vpp);
2217                 else
2218                         error = hammer2_vfs_vget(mp, NULL, inum, vpp);
2219         } else {
2220                 error = 0;
2221         }
2222         if (error)
2223                 kprintf("fhtovp: %016jx -> %p, %d\n", inum, *vpp, error);
2224         return error;
2225 }
2226
2227 static
2228 int
2229 hammer2_vfs_checkexp(struct mount *mp, struct sockaddr *nam,
2230                  int *exflagsp, struct ucred **credanonp)
2231 {
2232         hammer2_pfs_t *pmp;
2233         struct netcred *np;
2234         int error;
2235
2236         pmp = MPTOPMP(mp);
2237         np = vfs_export_lookup(mp, &pmp->export, nam);
2238         if (np) {
2239                 *exflagsp = np->netc_exflags;
2240                 *credanonp = &np->netc_anon;
2241                 error = 0;
2242         } else {
2243                 error = EACCES;
2244         }
2245         return error;
2246 }
2247
2248 /*
2249  * Support code for hammer2_vfs_mount().  Read, verify, and install the volume
2250  * header into the HMP
2251  *
2252  * XXX read four volhdrs and use the one with the highest TID whos CRC
2253  *     matches.
2254  *
2255  * XXX check iCRCs.
2256  *
2257  * XXX For filesystems w/ less than 4 volhdrs, make sure to not write to
2258  *     nonexistant locations.
2259  *
2260  * XXX Record selected volhdr and ring updates to each of 4 volhdrs
2261  */
2262 static
2263 int
2264 hammer2_install_volume_header(hammer2_dev_t *hmp)
2265 {
2266         hammer2_volume_data_t *vd;
2267         struct buf *bp;
2268         hammer2_crc32_t crc0, crc, bcrc0, bcrc;
2269         int error_reported;
2270         int error;
2271         int valid;
2272         int i;
2273
2274         error_reported = 0;
2275         error = 0;
2276         valid = 0;
2277         bp = NULL;
2278
2279         /*
2280          * There are up to 4 copies of the volume header (syncs iterate
2281          * between them so there is no single master).  We don't trust the
2282          * volu_size field so we don't know precisely how large the filesystem
2283          * is, so depend on the OS to return an error if we go beyond the
2284          * block device's EOF.
2285          */
2286         for (i = 0; i < HAMMER2_NUM_VOLHDRS; i++) {
2287                 error = bread(hmp->devvp, i * HAMMER2_ZONE_BYTES64,
2288                               HAMMER2_VOLUME_BYTES, &bp);
2289                 if (error) {
2290                         brelse(bp);
2291                         bp = NULL;
2292                         continue;
2293                 }
2294
2295                 vd = (struct hammer2_volume_data *) bp->b_data;
2296                 if ((vd->magic != HAMMER2_VOLUME_ID_HBO) &&
2297                     (vd->magic != HAMMER2_VOLUME_ID_ABO)) {
2298                         brelse(bp);
2299                         bp = NULL;
2300                         continue;
2301                 }
2302
2303                 if (vd->magic == HAMMER2_VOLUME_ID_ABO) {
2304                         /* XXX: Reversed-endianness filesystem */
2305                         kprintf("hammer2: reverse-endian filesystem detected");
2306                         brelse(bp);
2307                         bp = NULL;
2308                         continue;
2309                 }
2310
2311                 crc = vd->icrc_sects[HAMMER2_VOL_ICRC_SECT0];
2312                 crc0 = hammer2_icrc32(bp->b_data + HAMMER2_VOLUME_ICRC0_OFF,
2313                                       HAMMER2_VOLUME_ICRC0_SIZE);
2314                 bcrc = vd->icrc_sects[HAMMER2_VOL_ICRC_SECT1];
2315                 bcrc0 = hammer2_icrc32(bp->b_data + HAMMER2_VOLUME_ICRC1_OFF,
2316                                        HAMMER2_VOLUME_ICRC1_SIZE);
2317                 if ((crc0 != crc) || (bcrc0 != bcrc)) {
2318                         kprintf("hammer2 volume header crc "
2319                                 "mismatch copy #%d %08x/%08x\n",
2320                                 i, crc0, crc);
2321                         error_reported = 1;
2322                         brelse(bp);
2323                         bp = NULL;
2324                         continue;
2325                 }
2326                 if (valid == 0 || hmp->voldata.mirror_tid < vd->mirror_tid) {
2327                         valid = 1;
2328                         hmp->voldata = *vd;
2329                         hmp->volhdrno = i;
2330                 }
2331                 brelse(bp);
2332                 bp = NULL;
2333         }
2334         if (valid) {
2335                 hmp->volsync = hmp->voldata;
2336                 error = 0;
2337                 if (error_reported || bootverbose || 1) { /* 1/DEBUG */
2338                         kprintf("hammer2: using volume header #%d\n",
2339                                 hmp->volhdrno);
2340                 }
2341         } else {
2342                 error = EINVAL;
2343                 kprintf("hammer2: no valid volume headers found!\n");
2344         }
2345         return (error);
2346 }
2347
2348 /*
2349  * This handles hysteresis on regular file flushes.  Because the BIOs are
2350  * routed to a thread it is possible for an excessive number to build up
2351  * and cause long front-end stalls long before the runningbuffspace limit
2352  * is hit, so we implement hammer2_flush_pipe to control the
2353  * hysteresis.
2354  *
2355  * This is a particular problem when compression is used.
2356  */
2357 void
2358 hammer2_lwinprog_ref(hammer2_pfs_t *pmp)
2359 {
2360         atomic_add_int(&pmp->count_lwinprog, 1);
2361 }
2362
2363 void
2364 hammer2_lwinprog_drop(hammer2_pfs_t *pmp)
2365 {
2366         int lwinprog;
2367
2368         lwinprog = atomic_fetchadd_int(&pmp->count_lwinprog, -1);
2369         if ((lwinprog & HAMMER2_LWINPROG_WAITING) &&
2370             (lwinprog & HAMMER2_LWINPROG_MASK) <= hammer2_flush_pipe * 2 / 3) {
2371                 atomic_clear_int(&pmp->count_lwinprog,
2372                                  HAMMER2_LWINPROG_WAITING);
2373                 wakeup(&pmp->count_lwinprog);
2374         }
2375         if ((lwinprog & HAMMER2_LWINPROG_WAITING0) &&
2376             (lwinprog & HAMMER2_LWINPROG_MASK) <= 0) {
2377                 atomic_clear_int(&pmp->count_lwinprog,
2378                                  HAMMER2_LWINPROG_WAITING0);
2379                 wakeup(&pmp->count_lwinprog);
2380         }
2381 }
2382
2383 void
2384 hammer2_lwinprog_wait(hammer2_pfs_t *pmp, int flush_pipe)
2385 {
2386         int lwinprog;
2387         int lwflag = (flush_pipe) ? HAMMER2_LWINPROG_WAITING :
2388                                     HAMMER2_LWINPROG_WAITING0;
2389
2390         for (;;) {
2391                 lwinprog = pmp->count_lwinprog;
2392                 cpu_ccfence();
2393                 if ((lwinprog & HAMMER2_LWINPROG_MASK) <= flush_pipe)
2394                         break;
2395                 tsleep_interlock(&pmp->count_lwinprog, 0);
2396                 atomic_set_int(&pmp->count_lwinprog, lwflag);
2397                 lwinprog = pmp->count_lwinprog;
2398                 if ((lwinprog & HAMMER2_LWINPROG_MASK) <= flush_pipe)
2399                         break;
2400                 tsleep(&pmp->count_lwinprog, PINTERLOCKED, "h2wpipe", hz);
2401         }
2402 }
2403
2404 /*
2405  * Manage excessive memory resource use for chain and related
2406  * structures.
2407  */
2408 void
2409 hammer2_pfs_memory_wait(hammer2_pfs_t *pmp)
2410 {
2411         uint32_t waiting;
2412         uint32_t count;
2413         uint32_t limit;
2414 #if 0
2415         static int zzticks;
2416 #endif
2417
2418         /*
2419          * Atomic check condition and wait.  Also do an early speedup of
2420          * the syncer to try to avoid hitting the wait.
2421          */
2422         for (;;) {
2423                 waiting = pmp->inmem_dirty_chains;
2424                 cpu_ccfence();
2425                 count = waiting & HAMMER2_DIRTYCHAIN_MASK;
2426
2427                 limit = pmp->mp->mnt_nvnodelistsize / 10;
2428                 if (limit < hammer2_limit_dirty_chains)
2429                         limit = hammer2_limit_dirty_chains;
2430                 if (limit < 1000)
2431                         limit = 1000;
2432
2433 #if 0
2434                 if ((int)(ticks - zzticks) > hz) {
2435                         zzticks = ticks;
2436                         kprintf("count %ld %ld\n", count, limit);
2437                 }
2438 #endif
2439
2440                 /*
2441                  * Block if there are too many dirty chains present, wait
2442                  * for the flush to clean some out.
2443                  */
2444                 if (count > limit) {
2445                         tsleep_interlock(&pmp->inmem_dirty_chains, 0);
2446                         if (atomic_cmpset_int(&pmp->inmem_dirty_chains,
2447                                                waiting,
2448                                        waiting | HAMMER2_DIRTYCHAIN_WAITING)) {
2449                                 speedup_syncer(pmp->mp);
2450                                 tsleep(&pmp->inmem_dirty_chains, PINTERLOCKED,
2451                                        "chnmem", hz);
2452                         }
2453                         continue;       /* loop on success or fail */
2454                 }
2455
2456                 /*
2457                  * Try to start an early flush before we are forced to block.
2458                  */
2459                 if (count > limit * 7 / 10)
2460                         speedup_syncer(pmp->mp);
2461                 break;
2462         }
2463 }
2464
2465 void
2466 hammer2_pfs_memory_inc(hammer2_pfs_t *pmp)
2467 {
2468         if (pmp) {
2469                 atomic_add_int(&pmp->inmem_dirty_chains, 1);
2470         }
2471 }
2472
2473 void
2474 hammer2_pfs_memory_wakeup(hammer2_pfs_t *pmp)
2475 {
2476         uint32_t waiting;
2477
2478         if (pmp == NULL)
2479                 return;
2480
2481         for (;;) {
2482                 waiting = pmp->inmem_dirty_chains;
2483                 cpu_ccfence();
2484                 if (atomic_cmpset_int(&pmp->inmem_dirty_chains,
2485                                        waiting,
2486                                        (waiting - 1) &
2487                                         ~HAMMER2_DIRTYCHAIN_WAITING)) {
2488                         break;
2489                 }
2490         }
2491
2492         if (waiting & HAMMER2_DIRTYCHAIN_WAITING)
2493                 wakeup(&pmp->inmem_dirty_chains);
2494 }
2495
2496 /*
2497  * Debugging
2498  */
2499 void
2500 hammer2_dump_chain(hammer2_chain_t *chain, int tab, int *countp, char pfx)
2501 {
2502         hammer2_chain_t *scan;
2503         hammer2_chain_t *parent;
2504
2505         --*countp;
2506         if (*countp == 0) {
2507                 kprintf("%*.*s...\n", tab, tab, "");
2508                 return;
2509         }
2510         if (*countp < 0)
2511                 return;
2512         kprintf("%*.*s%c-chain %p.%d %016jx/%d mir=%016jx\n",
2513                 tab, tab, "", pfx,
2514                 chain, chain->bref.type,
2515                 chain->bref.key, chain->bref.keybits,
2516                 chain->bref.mirror_tid);
2517
2518         kprintf("%*.*s      [%08x] (%s) refs=%d",
2519                 tab, tab, "",
2520                 chain->flags,
2521                 ((chain->bref.type == HAMMER2_BREF_TYPE_INODE &&
2522                 chain->data) ?  (char *)chain->data->ipdata.filename : "?"),
2523                 chain->refs);
2524
2525         parent = chain->parent;
2526         if (parent)
2527                 kprintf("\n%*.*s      p=%p [pflags %08x prefs %d",
2528                         tab, tab, "",
2529                         parent, parent->flags, parent->refs);
2530         if (RB_EMPTY(&chain->core.rbtree)) {
2531                 kprintf("\n");
2532         } else {
2533                 kprintf(" {\n");
2534                 RB_FOREACH(scan, hammer2_chain_tree, &chain->core.rbtree)
2535                         hammer2_dump_chain(scan, tab + 4, countp, 'a');
2536                 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE && chain->data)
2537                         kprintf("%*.*s}(%s)\n", tab, tab, "",
2538                                 chain->data->ipdata.filename);
2539                 else
2540                         kprintf("%*.*s}\n", tab, tab, "");
2541         }
2542 }