hammer2 - error handling 2/N (chain_lookup/chain_next)
[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 static struct hammer2_mntlist hammer2_mntlist;
76
77 struct hammer2_pfslist hammer2_pfslist;
78 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_always_compress = 0;        /* always try to compress */
85 int hammer2_inval_enable = 0;
86 int hammer2_flush_pipe = 100;
87 int hammer2_synchronous_flush = 1;
88 int hammer2_dio_count;
89 int hammer2_limit_dio = 256;
90 long hammer2_chain_allocs;
91 long hammer2_chain_frees;
92 long hammer2_limit_dirty_chains;
93 long hammer2_count_modified_chains;
94 long hammer2_iod_invals;
95 long hammer2_iod_file_read;
96 long hammer2_iod_meta_read;
97 long hammer2_iod_indr_read;
98 long hammer2_iod_fmap_read;
99 long hammer2_iod_volu_read;
100 long hammer2_iod_file_write;
101 long hammer2_iod_file_wembed;
102 long hammer2_iod_file_wzero;
103 long hammer2_iod_file_wdedup;
104 long hammer2_iod_meta_write;
105 long hammer2_iod_indr_write;
106 long hammer2_iod_fmap_write;
107 long hammer2_iod_volu_write;
108
109 MALLOC_DECLARE(M_HAMMER2_CBUFFER);
110 MALLOC_DEFINE(M_HAMMER2_CBUFFER, "HAMMER2-compbuffer",
111                 "Buffer used for compression.");
112
113 MALLOC_DECLARE(M_HAMMER2_DEBUFFER);
114 MALLOC_DEFINE(M_HAMMER2_DEBUFFER, "HAMMER2-decompbuffer",
115                 "Buffer used for decompression.");
116
117 SYSCTL_NODE(_vfs, OID_AUTO, hammer2, CTLFLAG_RW, 0, "HAMMER2 filesystem");
118
119 SYSCTL_INT(_vfs_hammer2, OID_AUTO, debug, CTLFLAG_RW,
120            &hammer2_debug, 0, "");
121 SYSCTL_INT(_vfs_hammer2, OID_AUTO, cluster_read, CTLFLAG_RW,
122            &hammer2_cluster_read, 0, "");
123 SYSCTL_INT(_vfs_hammer2, OID_AUTO, cluster_write, CTLFLAG_RW,
124            &hammer2_cluster_write, 0, "");
125 SYSCTL_INT(_vfs_hammer2, OID_AUTO, dedup_enable, CTLFLAG_RW,
126            &hammer2_dedup_enable, 0, "");
127 SYSCTL_INT(_vfs_hammer2, OID_AUTO, always_compress, CTLFLAG_RW,
128            &hammer2_always_compress, 0, "");
129 SYSCTL_INT(_vfs_hammer2, OID_AUTO, inval_enable, CTLFLAG_RW,
130            &hammer2_inval_enable, 0, "");
131 SYSCTL_INT(_vfs_hammer2, OID_AUTO, flush_pipe, CTLFLAG_RW,
132            &hammer2_flush_pipe, 0, "");
133 SYSCTL_INT(_vfs_hammer2, OID_AUTO, synchronous_flush, CTLFLAG_RW,
134            &hammer2_synchronous_flush, 0, "");
135 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, chain_allocs, CTLFLAG_RW,
136            &hammer2_chain_allocs, 0, "");
137 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, chain_frees, CTLFLAG_RW,
138            &hammer2_chain_frees, 0, "");
139 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, limit_dirty_chains, CTLFLAG_RW,
140            &hammer2_limit_dirty_chains, 0, "");
141 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, count_modified_chains, CTLFLAG_RW,
142            &hammer2_count_modified_chains, 0, "");
143 SYSCTL_INT(_vfs_hammer2, OID_AUTO, dio_count, CTLFLAG_RD,
144            &hammer2_dio_count, 0, "");
145 SYSCTL_INT(_vfs_hammer2, OID_AUTO, limit_dio, CTLFLAG_RW,
146            &hammer2_limit_dio, 0, "");
147
148 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_invals, CTLFLAG_RW,
149            &hammer2_iod_invals, 0, "");
150 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_read, CTLFLAG_RW,
151            &hammer2_iod_file_read, 0, "");
152 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_meta_read, CTLFLAG_RW,
153            &hammer2_iod_meta_read, 0, "");
154 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_indr_read, CTLFLAG_RW,
155            &hammer2_iod_indr_read, 0, "");
156 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_fmap_read, CTLFLAG_RW,
157            &hammer2_iod_fmap_read, 0, "");
158 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_volu_read, CTLFLAG_RW,
159            &hammer2_iod_volu_read, 0, "");
160
161 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_write, CTLFLAG_RW,
162            &hammer2_iod_file_write, 0, "");
163 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_wembed, CTLFLAG_RW,
164            &hammer2_iod_file_wembed, 0, "");
165 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_wzero, CTLFLAG_RW,
166            &hammer2_iod_file_wzero, 0, "");
167 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_wdedup, CTLFLAG_RW,
168            &hammer2_iod_file_wdedup, 0, "");
169 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_meta_write, CTLFLAG_RW,
170            &hammer2_iod_meta_write, 0, "");
171 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_indr_write, CTLFLAG_RW,
172            &hammer2_iod_indr_write, 0, "");
173 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_fmap_write, CTLFLAG_RW,
174            &hammer2_iod_fmap_write, 0, "");
175 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_volu_write, CTLFLAG_RW,
176            &hammer2_iod_volu_write, 0, "");
177
178 long hammer2_check_icrc32;
179 long hammer2_check_xxhash64;
180 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, check_icrc32, CTLFLAG_RW,
181            &hammer2_check_icrc32, 0, "");
182 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, check_xxhash64, CTLFLAG_RW,
183            &hammer2_check_xxhash64, 0, "");
184
185 static int hammer2_vfs_init(struct vfsconf *conf);
186 static int hammer2_vfs_uninit(struct vfsconf *vfsp);
187 static int hammer2_vfs_mount(struct mount *mp, char *path, caddr_t data,
188                                 struct ucred *cred);
189 static int hammer2_remount(hammer2_dev_t *, struct mount *, char *,
190                                 struct vnode *, struct ucred *);
191 static int hammer2_recovery(hammer2_dev_t *hmp);
192 static int hammer2_vfs_unmount(struct mount *mp, int mntflags);
193 static int hammer2_vfs_root(struct mount *mp, struct vnode **vpp);
194 static int hammer2_vfs_statfs(struct mount *mp, struct statfs *sbp,
195                                 struct ucred *cred);
196 static int hammer2_vfs_statvfs(struct mount *mp, struct statvfs *sbp,
197                                 struct ucred *cred);
198 static int hammer2_vfs_fhtovp(struct mount *mp, struct vnode *rootvp,
199                                 struct fid *fhp, struct vnode **vpp);
200 static int hammer2_vfs_vptofh(struct vnode *vp, struct fid *fhp);
201 static int hammer2_vfs_checkexp(struct mount *mp, struct sockaddr *nam,
202                                 int *exflagsp, struct ucred **credanonp);
203
204 static int hammer2_install_volume_header(hammer2_dev_t *hmp);
205 static int hammer2_sync_scan2(struct mount *mp, struct vnode *vp, void *data);
206
207 static void hammer2_update_pmps(hammer2_dev_t *hmp);
208
209 static void hammer2_mount_helper(struct mount *mp, hammer2_pfs_t *pmp);
210 static void hammer2_unmount_helper(struct mount *mp, hammer2_pfs_t *pmp,
211                                 hammer2_dev_t *hmp);
212
213 /*
214  * HAMMER2 vfs operations.
215  */
216 static struct vfsops hammer2_vfsops = {
217         .vfs_init       = hammer2_vfs_init,
218         .vfs_uninit     = hammer2_vfs_uninit,
219         .vfs_sync       = hammer2_vfs_sync,
220         .vfs_mount      = hammer2_vfs_mount,
221         .vfs_unmount    = hammer2_vfs_unmount,
222         .vfs_root       = hammer2_vfs_root,
223         .vfs_statfs     = hammer2_vfs_statfs,
224         .vfs_statvfs    = hammer2_vfs_statvfs,
225         .vfs_vget       = hammer2_vfs_vget,
226         .vfs_vptofh     = hammer2_vfs_vptofh,
227         .vfs_fhtovp     = hammer2_vfs_fhtovp,
228         .vfs_checkexp   = hammer2_vfs_checkexp
229 };
230
231 MALLOC_DEFINE(M_HAMMER2, "HAMMER2-mount", "");
232
233 VFS_SET(hammer2_vfsops, hammer2, VFCF_MPSAFE);
234 MODULE_VERSION(hammer2, 1);
235
236 static
237 int
238 hammer2_vfs_init(struct vfsconf *conf)
239 {
240         static struct objcache_malloc_args margs_read;
241         static struct objcache_malloc_args margs_write;
242         static struct objcache_malloc_args margs_vop;
243
244         int error;
245
246         error = 0;
247
248         /*
249          * A large DIO cache is needed to retain dedup enablement masks.
250          * The bulkfree code clears related masks as part of the disk block
251          * recycling algorithm, preventing it from being used for a later
252          * dedup.
253          *
254          * NOTE: A large buffer cache can actually interfere with dedup
255          *       operation because we dedup based on media physical buffers
256          *       and not logical buffers.  Try to make the DIO chace large
257          *       enough to avoid this problem, but also cap it.
258          */
259         hammer2_limit_dio = nbuf * 2;
260         if (hammer2_limit_dio > 100000)
261                 hammer2_limit_dio = 100000;
262
263         if (HAMMER2_BLOCKREF_BYTES != sizeof(struct hammer2_blockref))
264                 error = EINVAL;
265         if (HAMMER2_INODE_BYTES != sizeof(struct hammer2_inode_data))
266                 error = EINVAL;
267         if (HAMMER2_VOLUME_BYTES != sizeof(struct hammer2_volume_data))
268                 error = EINVAL;
269
270         if (error)
271                 kprintf("HAMMER2 structure size mismatch; cannot continue.\n");
272         
273         margs_read.objsize = 65536;
274         margs_read.mtype = M_HAMMER2_DEBUFFER;
275         
276         margs_write.objsize = 32768;
277         margs_write.mtype = M_HAMMER2_CBUFFER;
278
279         margs_vop.objsize = sizeof(hammer2_xop_t);
280         margs_vop.mtype = M_HAMMER2;
281         
282         /*
283          * Note thaht for the XOPS cache we want backing store allocations
284          * to use M_ZERO.  This is not allowed in objcache_get() (to avoid
285          * confusion), so use the backing store function that does it.  This
286          * means that initial XOPS objects are zerod but REUSED objects are
287          * not.  So we are responsible for cleaning the object up sufficiently
288          * for our needs before objcache_put()ing it back (typically just the
289          * FIFO indices).
290          */
291         cache_buffer_read = objcache_create(margs_read.mtype->ks_shortdesc,
292                                 0, 1, NULL, NULL, NULL,
293                                 objcache_malloc_alloc,
294                                 objcache_malloc_free,
295                                 &margs_read);
296         cache_buffer_write = objcache_create(margs_write.mtype->ks_shortdesc,
297                                 0, 1, NULL, NULL, NULL,
298                                 objcache_malloc_alloc,
299                                 objcache_malloc_free,
300                                 &margs_write);
301         cache_xops = objcache_create(margs_vop.mtype->ks_shortdesc,
302                                 0, 1, NULL, NULL, NULL,
303                                 objcache_malloc_alloc_zero,
304                                 objcache_malloc_free,
305                                 &margs_vop);
306
307
308         lockinit(&hammer2_mntlk, "mntlk", 0, 0);
309         TAILQ_INIT(&hammer2_mntlist);
310         TAILQ_INIT(&hammer2_pfslist);
311
312         hammer2_limit_dirty_chains = maxvnodes / 10;
313         if (hammer2_limit_dirty_chains > HAMMER2_LIMIT_DIRTY_CHAINS)
314                 hammer2_limit_dirty_chains = HAMMER2_LIMIT_DIRTY_CHAINS;
315
316         return (error);
317 }
318
319 static
320 int
321 hammer2_vfs_uninit(struct vfsconf *vfsp __unused)
322 {
323         objcache_destroy(cache_buffer_read);
324         objcache_destroy(cache_buffer_write);
325         objcache_destroy(cache_xops);
326         return 0;
327 }
328
329 /*
330  * Core PFS allocator.  Used to allocate or reference the pmp structure
331  * for PFS cluster mounts and the spmp structure for media (hmp) structures.
332  * The pmp can be passed in or loaded by this function using the chain and
333  * inode data.
334  *
335  * pmp->modify_tid tracks new modify_tid transaction ids for front-end
336  * transactions.  Note that synchronization does not use this field.
337  * (typically frontend operations and synchronization cannot run on the
338  * same PFS node at the same time).
339  *
340  * XXX check locking
341  */
342 hammer2_pfs_t *
343 hammer2_pfsalloc(hammer2_chain_t *chain,
344                  const hammer2_inode_data_t *ripdata,
345                  hammer2_tid_t modify_tid, hammer2_dev_t *force_local)
346 {
347         hammer2_pfs_t *pmp;
348         hammer2_inode_t *iroot;
349         int count;
350         int i;
351         int j;
352
353         pmp = NULL;
354
355         /*
356          * Locate or create the PFS based on the cluster id.  If ripdata
357          * is NULL this is a spmp which is unique and is always allocated.
358          *
359          * If the device is mounted in local mode all PFSs are considered
360          * independent and not part of any cluster (for debugging only).
361          */
362         if (ripdata) {
363                 TAILQ_FOREACH(pmp, &hammer2_pfslist, mntentry) {
364                         if (force_local != pmp->force_local)
365                                 continue;
366                         if (force_local == NULL &&
367                             bcmp(&pmp->pfs_clid, &ripdata->meta.pfs_clid,
368                                  sizeof(pmp->pfs_clid)) == 0) {
369                                         break;
370                         } else if (force_local && pmp->pfs_names[0] &&
371                             strcmp(pmp->pfs_names[0], ripdata->filename) == 0) {
372                                         break;
373                         }
374                 }
375         }
376
377         if (pmp == NULL) {
378                 pmp = kmalloc(sizeof(*pmp), M_HAMMER2, M_WAITOK | M_ZERO);
379                 pmp->force_local = force_local;
380                 hammer2_trans_manage_init(pmp);
381                 kmalloc_create(&pmp->minode, "HAMMER2-inodes");
382                 kmalloc_create(&pmp->mmsg, "HAMMER2-pfsmsg");
383                 lockinit(&pmp->lock, "pfslk", 0, 0);
384                 lockinit(&pmp->lock_nlink, "h2nlink", 0, 0);
385                 spin_init(&pmp->inum_spin, "hm2pfsalloc_inum");
386                 spin_init(&pmp->xop_spin, "h2xop");
387                 spin_init(&pmp->lru_spin, "h2lru");
388                 RB_INIT(&pmp->inum_tree);
389                 TAILQ_INIT(&pmp->sideq);
390                 TAILQ_INIT(&pmp->lru_list);
391                 spin_init(&pmp->list_spin, "hm2pfsalloc_list");
392
393                 /*
394                  * Distribute backend operations to threads
395                  */
396                 for (i = 0; i < HAMMER2_XOPGROUPS; ++i)
397                         hammer2_xop_group_init(pmp, &pmp->xop_groups[i]);
398
399                 /*
400                  * Save the last media transaction id for the flusher.  Set
401                  * initial 
402                  */
403                 if (ripdata)
404                         pmp->pfs_clid = ripdata->meta.pfs_clid;
405                 TAILQ_INSERT_TAIL(&hammer2_pfslist, pmp, mntentry);
406
407                 /*
408                  * The synchronization thread may start too early, make
409                  * sure it stays frozen until we are ready to let it go.
410                  * XXX
411                  */
412                 /*
413                 pmp->primary_thr.flags = HAMMER2_THREAD_FROZEN |
414                                          HAMMER2_THREAD_REMASTER;
415                 */
416         }
417
418         /*
419          * Create the PFS's root inode and any missing XOP helper threads.
420          */
421         if ((iroot = pmp->iroot) == NULL) {
422                 iroot = hammer2_inode_get(pmp, NULL, NULL, -1);
423                 if (ripdata)
424                         iroot->meta = ripdata->meta;
425                 pmp->iroot = iroot;
426                 hammer2_inode_ref(iroot);
427                 hammer2_inode_unlock(iroot);
428         }
429
430         /*
431          * Stop here if no chain is passed in.
432          */
433         if (chain == NULL)
434                 goto done;
435
436         /*
437          * When a chain is passed in we must add it to the PFS's root
438          * inode, update pmp->pfs_types[], and update the syncronization
439          * threads.
440          *
441          * When forcing local mode, mark the PFS as a MASTER regardless.
442          *
443          * At the moment empty spots can develop due to removals or failures.
444          * Ultimately we want to re-fill these spots but doing so might
445          * confused running code. XXX
446          */
447         hammer2_inode_ref(iroot);
448         hammer2_mtx_ex(&iroot->lock);
449         j = iroot->cluster.nchains;
450
451         kprintf("add PFS to pmp %p[%d]\n", pmp, j);
452
453         if (j == HAMMER2_MAXCLUSTER) {
454                 kprintf("hammer2_mount: cluster full!\n");
455                 /* XXX fatal error? */
456         } else {
457                 KKASSERT(chain->pmp == NULL);
458                 chain->pmp = pmp;
459                 hammer2_chain_ref(chain);
460                 iroot->cluster.array[j].chain = chain;
461                 if (force_local)
462                         pmp->pfs_types[j] = HAMMER2_PFSTYPE_MASTER;
463                 else
464                         pmp->pfs_types[j] = ripdata->meta.pfs_type;
465                 pmp->pfs_names[j] = kstrdup(ripdata->filename, M_HAMMER2);
466                 pmp->pfs_hmps[j] = chain->hmp;
467
468                 /*
469                  * If the PFS is already mounted we must account
470                  * for the mount_count here.
471                  */
472                 if (pmp->mp)
473                         ++chain->hmp->mount_count;
474
475                 /*
476                  * May have to fixup dirty chain tracking.  Previous
477                  * pmp was NULL so nothing to undo.
478                  */
479                 if (chain->flags & HAMMER2_CHAIN_MODIFIED)
480                         hammer2_pfs_memory_inc(pmp);
481                 ++j;
482         }
483         iroot->cluster.nchains = j;
484
485         /*
486          * Update nmasters from any PFS inode which is part of the cluster.
487          * It is possible that this will result in a value which is too
488          * high.  MASTER PFSs are authoritative for pfs_nmasters and will
489          * override this value later on.
490          *
491          * (This informs us of masters that might not currently be
492          *  discoverable by this mount).
493          */
494         if (ripdata && pmp->pfs_nmasters < ripdata->meta.pfs_nmasters) {
495                 pmp->pfs_nmasters = ripdata->meta.pfs_nmasters;
496         }
497
498         /*
499          * Count visible masters.  Masters are usually added with
500          * ripdata->meta.pfs_nmasters set to 1.  This detects when there
501          * are more (XXX and must update the master inodes).
502          */
503         count = 0;
504         for (i = 0; i < iroot->cluster.nchains; ++i) {
505                 if (pmp->pfs_types[i] == HAMMER2_PFSTYPE_MASTER)
506                         ++count;
507         }
508         if (pmp->pfs_nmasters < count)
509                 pmp->pfs_nmasters = count;
510
511         /*
512          * Create missing synchronization and support threads.
513          *
514          * Single-node masters (including snapshots) have nothing to
515          * synchronize and do not require this thread.
516          *
517          * Multi-node masters or any number of soft masters, slaves, copy,
518          * or other PFS types need the thread.
519          *
520          * Each thread is responsible for its particular cluster index.
521          * We use independent threads so stalls or mismatches related to
522          * any given target do not affect other targets.
523          */
524         for (i = 0; i < iroot->cluster.nchains; ++i) {
525                 /*
526                  * Single-node masters (including snapshots) have nothing
527                  * to synchronize and will make direct xops support calls,
528                  * thus they do not require this thread.
529                  *
530                  * Note that there can be thousands of snapshots.  We do not
531                  * want to create thousands of threads.
532                  */
533                 if (pmp->pfs_nmasters <= 1 &&
534                     pmp->pfs_types[i] == HAMMER2_PFSTYPE_MASTER) {
535                         continue;
536                 }
537
538                 /*
539                  * Sync support thread
540                  */
541                 if (pmp->sync_thrs[i].td == NULL) {
542                         hammer2_thr_create(&pmp->sync_thrs[i], pmp, NULL,
543                                            "h2nod", i, -1,
544                                            hammer2_primary_sync_thread);
545                 }
546         }
547
548         /*
549          * Create missing Xop threads
550          *
551          * NOTE: We create helper threads for all mounted PFSs or any
552          *       PFSs with 2+ nodes (so the sync thread can update them,
553          *       even if not mounted).
554          */
555         if (pmp->mp || iroot->cluster.nchains >= 2)
556                 hammer2_xop_helper_create(pmp);
557
558         hammer2_mtx_unlock(&iroot->lock);
559         hammer2_inode_drop(iroot);
560 done:
561         return pmp;
562 }
563
564 /*
565  * Deallocate an element of a probed PFS.  If destroying and this is a
566  * MASTER, adjust nmasters.
567  *
568  * This function does not physically destroy the PFS element in its device
569  * under the super-root  (see hammer2_ioctl_pfs_delete()).
570  */
571 void
572 hammer2_pfsdealloc(hammer2_pfs_t *pmp, int clindex, int destroying)
573 {
574         hammer2_inode_t *iroot;
575         hammer2_chain_t *chain;
576         int j;
577
578         /*
579          * Cleanup our reference on iroot.  iroot is (should) not be needed
580          * by the flush code.
581          */
582         iroot = pmp->iroot;
583         if (iroot) {
584                 /*
585                  * Stop synchronizing
586                  *
587                  * XXX flush after acquiring the iroot lock.
588                  * XXX clean out the cluster index from all inode structures.
589                  */
590                 hammer2_thr_delete(&pmp->sync_thrs[clindex]);
591
592                 /*
593                  * Remove the cluster index from the group.  If destroying
594                  * the PFS and this is a master, adjust pfs_nmasters.
595                  */
596                 hammer2_mtx_ex(&iroot->lock);
597                 chain = iroot->cluster.array[clindex].chain;
598                 iroot->cluster.array[clindex].chain = NULL;
599
600                 switch(pmp->pfs_types[clindex]) {
601                 case HAMMER2_PFSTYPE_MASTER:
602                         if (destroying && pmp->pfs_nmasters > 0)
603                                 --pmp->pfs_nmasters;
604                         /* XXX adjust ripdata->meta.pfs_nmasters */
605                         break;
606                 default:
607                         break;
608                 }
609                 pmp->pfs_types[clindex] = HAMMER2_PFSTYPE_NONE;
610
611                 hammer2_mtx_unlock(&iroot->lock);
612
613                 /*
614                  * Release the chain.
615                  */
616                 if (chain) {
617                         atomic_set_int(&chain->flags, HAMMER2_CHAIN_RELEASE);
618                         hammer2_chain_drop(chain);
619                 }
620
621                 /*
622                  * Terminate all XOP threads for the cluster index.
623                  */
624                 for (j = 0; j < HAMMER2_XOPGROUPS; ++j)
625                         hammer2_thr_delete(&pmp->xop_groups[j].thrs[clindex]);
626         }
627 }
628
629 /*
630  * Destroy a PFS, typically only occurs after the last mount on a device
631  * has gone away.
632  */
633 static void
634 hammer2_pfsfree(hammer2_pfs_t *pmp)
635 {
636         hammer2_inode_t *iroot;
637         hammer2_chain_t *chain;
638         int i;
639         int j;
640
641         /*
642          * Cleanup our reference on iroot.  iroot is (should) not be needed
643          * by the flush code.
644          */
645         TAILQ_REMOVE(&hammer2_pfslist, pmp, mntentry);
646
647         iroot = pmp->iroot;
648         if (iroot) {
649                 for (i = 0; i < iroot->cluster.nchains; ++i) {
650                         hammer2_thr_delete(&pmp->sync_thrs[i]);
651                         for (j = 0; j < HAMMER2_XOPGROUPS; ++j)
652                                 hammer2_thr_delete(&pmp->xop_groups[j].thrs[i]);
653                 }
654 #if REPORT_REFS_ERRORS
655                 if (pmp->iroot->refs != 1)
656                         kprintf("PMP->IROOT %p REFS WRONG %d\n",
657                                 pmp->iroot, pmp->iroot->refs);
658 #else
659                 KKASSERT(pmp->iroot->refs == 1);
660 #endif
661                 /* ref for pmp->iroot */
662                 hammer2_inode_drop(pmp->iroot);
663                 pmp->iroot = NULL;
664         }
665
666         /*
667          * Cleanup chains remaining on LRU list.
668          */
669         kprintf("pfsfree: %p lrucount=%d\n", pmp, pmp->lru_count);
670         while ((chain = TAILQ_FIRST(&pmp->lru_list)) != NULL) {
671                 hammer2_chain_ref(chain);
672                 atomic_set_int(&chain->flags, HAMMER2_CHAIN_RELEASE);
673                 hammer2_chain_drop(chain);
674         }
675
676         /*
677          * Free remaining pmp resources
678          */
679         kmalloc_destroy(&pmp->mmsg);
680         kmalloc_destroy(&pmp->minode);
681
682         kfree(pmp, M_HAMMER2);
683 }
684
685 /*
686  * Remove all references to hmp from the pfs list.  Any PFS which becomes
687  * empty is terminated and freed.
688  *
689  * XXX inefficient.
690  */
691 static void
692 hammer2_pfsfree_scan(hammer2_dev_t *hmp)
693 {
694         hammer2_pfs_t *pmp;
695         hammer2_inode_t *iroot;
696         hammer2_chain_t *rchain;
697         int didfreeze;
698         int i;
699         int j;
700
701 again:
702         TAILQ_FOREACH(pmp, &hammer2_pfslist, mntentry) {
703                 if ((iroot = pmp->iroot) == NULL)
704                         continue;
705                 if (hmp->spmp == pmp) {
706                         kprintf("unmount hmp %p remove spmp %p\n",
707                                 hmp, pmp);
708                         hmp->spmp = NULL;
709                 }
710
711                 /*
712                  * Determine if this PFS is affected.  If it is we must
713                  * freeze all management threads and lock its iroot.
714                  *
715                  * Freezing a management thread forces it idle, operations
716                  * in-progress will be aborted and it will have to start
717                  * over again when unfrozen, or exit if told to exit.
718                  */
719                 for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
720                         if (pmp->pfs_hmps[i] == hmp)
721                                 break;
722                 }
723                 if (i != HAMMER2_MAXCLUSTER) {
724                         /*
725                          * Make sure all synchronization threads are locked
726                          * down.
727                          */
728                         for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
729                                 if (pmp->pfs_hmps[i] == NULL)
730                                         continue;
731                                 hammer2_thr_freeze_async(&pmp->sync_thrs[i]);
732                                 for (j = 0; j < HAMMER2_XOPGROUPS; ++j) {
733                                         hammer2_thr_freeze_async(
734                                                 &pmp->xop_groups[j].thrs[i]);
735                                 }
736                         }
737                         for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
738                                 if (pmp->pfs_hmps[i] == NULL)
739                                         continue;
740                                 hammer2_thr_freeze(&pmp->sync_thrs[i]);
741                                 for (j = 0; j < HAMMER2_XOPGROUPS; ++j) {
742                                         hammer2_thr_freeze(
743                                                 &pmp->xop_groups[j].thrs[i]);
744                                 }
745                         }
746
747                         /*
748                          * Lock the inode and clean out matching chains.
749                          * Note that we cannot use hammer2_inode_lock_*()
750                          * here because that would attempt to validate the
751                          * cluster that we are in the middle of ripping
752                          * apart.
753                          *
754                          * WARNING! We are working directly on the inodes
755                          *          embedded cluster.
756                          */
757                         hammer2_mtx_ex(&iroot->lock);
758
759                         /*
760                          * Remove the chain from matching elements of the PFS.
761                          */
762                         for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
763                                 if (pmp->pfs_hmps[i] != hmp)
764                                         continue;
765                                 hammer2_thr_delete(&pmp->sync_thrs[i]);
766                                 for (j = 0; j < HAMMER2_XOPGROUPS; ++j) {
767                                         hammer2_thr_delete(
768                                                 &pmp->xop_groups[j].thrs[i]);
769                                 }
770                                 rchain = iroot->cluster.array[i].chain;
771                                 iroot->cluster.array[i].chain = NULL;
772                                 pmp->pfs_types[i] = 0;
773                                 if (pmp->pfs_names[i]) {
774                                         kfree(pmp->pfs_names[i], M_HAMMER2);
775                                         pmp->pfs_names[i] = NULL;
776                                 }
777                                 if (rchain) {
778                                         hammer2_chain_drop(rchain);
779                                         /* focus hint */
780                                         if (iroot->cluster.focus == rchain)
781                                                 iroot->cluster.focus = NULL;
782                                 }
783                                 pmp->pfs_hmps[i] = NULL;
784                         }
785                         hammer2_mtx_unlock(&iroot->lock);
786                         didfreeze = 1;  /* remaster, unfreeze down below */
787                 } else {
788                         didfreeze = 0;
789                 }
790
791                 /*
792                  * Cleanup trailing chains.  Gaps may remain.
793                  */
794                 for (i = HAMMER2_MAXCLUSTER - 1; i >= 0; --i) {
795                         if (pmp->pfs_hmps[i])
796                                 break;
797                 }
798                 iroot->cluster.nchains = i + 1;
799
800                 /*
801                  * If the PMP has no elements remaining we can destroy it.
802                  * (this will transition management threads from frozen->exit).
803                  */
804                 if (iroot->cluster.nchains == 0) {
805                         kprintf("unmount hmp %p last ref to PMP=%p\n",
806                                 hmp, pmp);
807                         hammer2_pfsfree(pmp);
808                         goto again;
809                 }
810
811                 /*
812                  * If elements still remain we need to set the REMASTER
813                  * flag and unfreeze it.
814                  */
815                 if (didfreeze) {
816                         for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
817                                 if (pmp->pfs_hmps[i] == NULL)
818                                         continue;
819                                 hammer2_thr_remaster(&pmp->sync_thrs[i]);
820                                 hammer2_thr_unfreeze(&pmp->sync_thrs[i]);
821                                 for (j = 0; j < HAMMER2_XOPGROUPS; ++j) {
822                                         hammer2_thr_remaster(
823                                                 &pmp->xop_groups[j].thrs[i]);
824                                         hammer2_thr_unfreeze(
825                                                 &pmp->xop_groups[j].thrs[i]);
826                                 }
827                         }
828                 }
829         }
830 }
831
832 /*
833  * Mount or remount HAMMER2 fileystem from physical media
834  *
835  *      mountroot
836  *              mp              mount point structure
837  *              path            NULL
838  *              data            <unused>
839  *              cred            <unused>
840  *
841  *      mount
842  *              mp              mount point structure
843  *              path            path to mount point
844  *              data            pointer to argument structure in user space
845  *                      volume  volume path (device@LABEL form)
846  *                      hflags  user mount flags
847  *              cred            user credentials
848  *
849  * RETURNS:     0       Success
850  *              !0      error number
851  */
852 static
853 int
854 hammer2_vfs_mount(struct mount *mp, char *path, caddr_t data,
855                   struct ucred *cred)
856 {
857         struct hammer2_mount_info info;
858         hammer2_pfs_t *pmp;
859         hammer2_pfs_t *spmp;
860         hammer2_dev_t *hmp;
861         hammer2_dev_t *force_local;
862         hammer2_key_t key_next;
863         hammer2_key_t key_dummy;
864         hammer2_key_t lhc;
865         struct vnode *devvp;
866         struct nlookupdata nd;
867         hammer2_chain_t *parent;
868         hammer2_chain_t *chain;
869         hammer2_cluster_t *cluster;
870         const hammer2_inode_data_t *ripdata;
871         hammer2_blockref_t bref;
872         struct file *fp;
873         char devstr[MNAMELEN];
874         size_t size;
875         size_t done;
876         char *dev;
877         char *label;
878         int ronly = 1;
879         int error;
880         int i;
881
882         hmp = NULL;
883         pmp = NULL;
884         dev = NULL;
885         label = NULL;
886         devvp = NULL;
887
888         kprintf("hammer2_mount\n");
889
890         if (path == NULL) {
891                 /*
892                  * Root mount
893                  */
894                 bzero(&info, sizeof(info));
895                 info.cluster_fd = -1;
896                 ksnprintf(devstr, sizeof(devstr), "%s",
897                           mp->mnt_stat.f_mntfromname);
898                 kprintf("hammer2_mount: root '%s'\n", devstr);
899         } else {
900                 /*
901                  * Non-root mount or updating a mount
902                  */
903                 error = copyin(data, &info, sizeof(info));
904                 if (error)
905                         return (error);
906
907                 error = copyinstr(info.volume, devstr, MNAMELEN - 1, &done);
908                 if (error)
909                         return (error);
910         }
911
912         /*
913          * Extract device and label, automatically mount @BOOT, @ROOT, or @DATA
914          * if no label specified, based on the partition id.  Error out if no
915          * partition id.  This is strictly a convenience to match the
916          * default label created by newfs_hammer2, our preference is
917          * that a label always be specified.
918          */
919         dev = devstr;
920         label = strchr(devstr, '@');
921         if (label && ((label + 1) - dev) > done)
922                 return (EINVAL);
923         if (label && label == devstr)
924                 return (EINVAL);
925         if (label == NULL || label[1] == 0) {
926                 char slice;
927
928                 if (label == NULL)
929                         label = devstr + strlen(devstr);
930                 slice = label[-1];
931                 switch(slice) {
932                 case 'a':
933                         label = "BOOT";
934                         break;
935                 case 'd':
936                         label = "ROOT";
937                         break;
938                 default:
939                         label = "DATA";
940                         break;
941                 }
942         } else {
943                 *label = '\0';
944                 label++;
945         }
946
947         kprintf("hammer2_mount: dev=\"%s\" label=\"%s\" rdonly=%d\n",
948                 dev, label, (mp->mnt_flag & MNT_RDONLY));
949
950         if (mp->mnt_flag & MNT_UPDATE) {
951                 /*
952                  * Update mount.  Note that pmp->iroot->cluster is
953                  * an inode-embedded cluster and thus cannot be
954                  * directly locked.
955                  *
956                  * XXX HAMMER2 needs to implement NFS export via
957                  *     mountctl.
958                  */
959                 pmp = MPTOPMP(mp);
960                 pmp->hflags = info.hflags;
961                 cluster = &pmp->iroot->cluster;
962                 for (i = 0; i < cluster->nchains; ++i) {
963                         if (cluster->array[i].chain == NULL)
964                                 continue;
965                         hmp = cluster->array[i].chain->hmp;
966                         devvp = hmp->devvp;
967                         error = hammer2_remount(hmp, mp, path,
968                                                 devvp, cred);
969                         if (error)
970                                 break;
971                 }
972
973                 return error;
974         }
975
976         /*
977          * HMP device mount
978          *
979          * If a path is specified and dev is not an empty string, lookup the
980          * name and verify that it referes to a block device.
981          *
982          * If a path is specified and dev is an empty string we fall through
983          * and locate the label in the hmp search.
984          */
985         if (path && *dev != 0) {
986                 error = nlookup_init(&nd, dev, UIO_SYSSPACE, NLC_FOLLOW);
987                 if (error == 0)
988                         error = nlookup(&nd);
989                 if (error == 0)
990                         error = cache_vref(&nd.nl_nch, nd.nl_cred, &devvp);
991                 nlookup_done(&nd);
992         } else if (path == NULL) {
993                 /* root mount */
994                 cdev_t cdev = kgetdiskbyname(dev);
995                 error = bdevvp(cdev, &devvp);
996                 if (error)
997                         kprintf("hammer2: cannot find '%s'\n", dev);
998         } else {
999                 /*
1000                  * We will locate the hmp using the label in the hmp loop.
1001                  */
1002                 error = 0;
1003         }
1004
1005         /*
1006          * Make sure its a block device.  Do not check to see if it is
1007          * already mounted until we determine that its a fresh H2 device.
1008          */
1009         if (error == 0 && devvp) {
1010                 vn_isdisk(devvp, &error);
1011         }
1012
1013         /*
1014          * Determine if the device has already been mounted.  After this
1015          * check hmp will be non-NULL if we are doing the second or more
1016          * hammer2 mounts from the same device.
1017          */
1018         lockmgr(&hammer2_mntlk, LK_EXCLUSIVE);
1019         if (devvp) {
1020                 /*
1021                  * Match the device.  Due to the way devfs works,
1022                  * we may not be able to directly match the vnode pointer,
1023                  * so also check to see if the underlying device matches.
1024                  */
1025                 TAILQ_FOREACH(hmp, &hammer2_mntlist, mntentry) {
1026                         if (hmp->devvp == devvp)
1027                                 break;
1028                         if (devvp->v_rdev &&
1029                             hmp->devvp->v_rdev == devvp->v_rdev) {
1030                                 break;
1031                         }
1032                 }
1033
1034                 /*
1035                  * If no match this may be a fresh H2 mount, make sure
1036                  * the device is not mounted on anything else.
1037                  */
1038                 if (hmp == NULL)
1039                         error = vfs_mountedon(devvp);
1040         } else if (error == 0) {
1041                 /*
1042                  * Match the label to a pmp already probed.
1043                  */
1044                 TAILQ_FOREACH(pmp, &hammer2_pfslist, mntentry) {
1045                         for (i = 0; i < HAMMER2_MAXCLUSTER; ++i) {
1046                                 if (pmp->pfs_names[i] &&
1047                                     strcmp(pmp->pfs_names[i], label) == 0) {
1048                                         hmp = pmp->pfs_hmps[i];
1049                                         break;
1050                                 }
1051                         }
1052                         if (hmp)
1053                                 break;
1054                 }
1055                 if (hmp == NULL)
1056                         error = ENOENT;
1057         }
1058
1059         /*
1060          * Open the device if this isn't a secondary mount and construct
1061          * the H2 device mount (hmp).
1062          */
1063         if (hmp == NULL) {
1064                 hammer2_chain_t *schain;
1065                 hammer2_xid_t xid;
1066
1067                 if (error == 0 && vcount(devvp) > 0) {
1068                         kprintf("Primary device already has references\n");
1069                         error = EBUSY;
1070                 }
1071
1072                 /*
1073                  * Now open the device
1074                  */
1075                 if (error == 0) {
1076                         ronly = ((mp->mnt_flag & MNT_RDONLY) != 0);
1077                         vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
1078                         error = vinvalbuf(devvp, V_SAVE, 0, 0);
1079                         if (error == 0) {
1080                                 error = VOP_OPEN(devvp,
1081                                              (ronly ? FREAD : FREAD | FWRITE),
1082                                              FSCRED, NULL);
1083                         }
1084                         vn_unlock(devvp);
1085                 }
1086                 if (error && devvp) {
1087                         vrele(devvp);
1088                         devvp = NULL;
1089                 }
1090                 if (error) {
1091                         lockmgr(&hammer2_mntlk, LK_RELEASE);
1092                         return error;
1093                 }
1094                 hmp = kmalloc(sizeof(*hmp), M_HAMMER2, M_WAITOK | M_ZERO);
1095                 ksnprintf(hmp->devrepname, sizeof(hmp->devrepname), "%s", dev);
1096                 hmp->ronly = ronly;
1097                 hmp->devvp = devvp;
1098                 hmp->hflags = info.hflags & HMNT2_DEVFLAGS;
1099                 kmalloc_create(&hmp->mchain, "HAMMER2-chains");
1100                 TAILQ_INSERT_TAIL(&hammer2_mntlist, hmp, mntentry);
1101                 RB_INIT(&hmp->iotree);
1102                 spin_init(&hmp->io_spin, "hm2mount_io");
1103                 spin_init(&hmp->list_spin, "hm2mount_list");
1104                 TAILQ_INIT(&hmp->flushq);
1105
1106                 lockinit(&hmp->vollk, "h2vol", 0, 0);
1107                 lockinit(&hmp->bulklk, "h2bulk", 0, 0);
1108                 lockinit(&hmp->bflock, "h2bflk", 0, 0);
1109
1110                 /*
1111                  * vchain setup. vchain.data is embedded.
1112                  * vchain.refs is initialized and will never drop to 0.
1113                  *
1114                  * NOTE! voldata is not yet loaded.
1115                  */
1116                 hmp->vchain.hmp = hmp;
1117                 hmp->vchain.refs = 1;
1118                 hmp->vchain.data = (void *)&hmp->voldata;
1119                 hmp->vchain.bref.type = HAMMER2_BREF_TYPE_VOLUME;
1120                 hmp->vchain.bref.data_off = 0 | HAMMER2_PBUFRADIX;
1121                 hmp->vchain.bref.mirror_tid = hmp->voldata.mirror_tid;
1122
1123                 hammer2_chain_core_init(&hmp->vchain);
1124                 /* hmp->vchain.u.xxx is left NULL */
1125
1126                 /*
1127                  * fchain setup.  fchain.data is embedded.
1128                  * fchain.refs is initialized and will never drop to 0.
1129                  *
1130                  * The data is not used but needs to be initialized to
1131                  * pass assertion muster.  We use this chain primarily
1132                  * as a placeholder for the freemap's top-level RBTREE
1133                  * so it does not interfere with the volume's topology
1134                  * RBTREE.
1135                  */
1136                 hmp->fchain.hmp = hmp;
1137                 hmp->fchain.refs = 1;
1138                 hmp->fchain.data = (void *)&hmp->voldata.freemap_blockset;
1139                 hmp->fchain.bref.type = HAMMER2_BREF_TYPE_FREEMAP;
1140                 hmp->fchain.bref.data_off = 0 | HAMMER2_PBUFRADIX;
1141                 hmp->fchain.bref.mirror_tid = hmp->voldata.freemap_tid;
1142                 hmp->fchain.bref.methods =
1143                         HAMMER2_ENC_CHECK(HAMMER2_CHECK_FREEMAP) |
1144                         HAMMER2_ENC_COMP(HAMMER2_COMP_NONE);
1145
1146                 hammer2_chain_core_init(&hmp->fchain);
1147                 /* hmp->fchain.u.xxx is left NULL */
1148
1149                 /*
1150                  * Install the volume header and initialize fields from
1151                  * voldata.
1152                  */
1153                 error = hammer2_install_volume_header(hmp);
1154                 if (error) {
1155                         hammer2_unmount_helper(mp, NULL, hmp);
1156                         lockmgr(&hammer2_mntlk, LK_RELEASE);
1157                         hammer2_vfs_unmount(mp, MNT_FORCE);
1158                         return error;
1159                 }
1160
1161                 /*
1162                  * Really important to get these right or flush will get
1163                  * confused.
1164                  */
1165                 hmp->spmp = hammer2_pfsalloc(NULL, NULL, 0, NULL);
1166                 kprintf("alloc spmp %p tid %016jx\n",
1167                         hmp->spmp, hmp->voldata.mirror_tid);
1168                 spmp = hmp->spmp;
1169
1170                 /*
1171                  * Dummy-up vchain and fchain's modify_tid.  mirror_tid
1172                  * is inherited from the volume header.
1173                  */
1174                 xid = 0;
1175                 hmp->vchain.bref.mirror_tid = hmp->voldata.mirror_tid;
1176                 hmp->vchain.bref.modify_tid = hmp->vchain.bref.mirror_tid;
1177                 hmp->vchain.pmp = spmp;
1178                 hmp->fchain.bref.mirror_tid = hmp->voldata.freemap_tid;
1179                 hmp->fchain.bref.modify_tid = hmp->fchain.bref.mirror_tid;
1180                 hmp->fchain.pmp = spmp;
1181
1182                 /*
1183                  * First locate the super-root inode, which is key 0
1184                  * relative to the volume header's blockset.
1185                  *
1186                  * Then locate the root inode by scanning the directory keyspace
1187                  * represented by the label.
1188                  */
1189                 parent = hammer2_chain_lookup_init(&hmp->vchain, 0);
1190                 schain = hammer2_chain_lookup(&parent, &key_dummy,
1191                                       HAMMER2_SROOT_KEY, HAMMER2_SROOT_KEY,
1192                                       &error, 0);
1193                 hammer2_chain_lookup_done(parent);
1194                 if (schain == NULL) {
1195                         kprintf("hammer2_mount: invalid super-root\n");
1196                         hammer2_unmount_helper(mp, NULL, hmp);
1197                         lockmgr(&hammer2_mntlk, LK_RELEASE);
1198                         hammer2_vfs_unmount(mp, MNT_FORCE);
1199                         return EINVAL;
1200                 }
1201                 if (schain->error) {
1202                         kprintf("hammer2_mount: error %s reading super-root\n",
1203                                 hammer2_error_str(schain->error));
1204                         hammer2_chain_unlock(schain);
1205                         hammer2_chain_drop(schain);
1206                         schain = NULL;
1207                         hammer2_unmount_helper(mp, NULL, hmp);
1208                         lockmgr(&hammer2_mntlk, LK_RELEASE);
1209                         hammer2_vfs_unmount(mp, MNT_FORCE);
1210                         return EINVAL;
1211                 }
1212
1213                 /*
1214                  * The super-root always uses an inode_tid of 1 when
1215                  * creating PFSs.
1216                  */
1217                 spmp->inode_tid = 1;
1218                 spmp->modify_tid = schain->bref.modify_tid + 1;
1219
1220                 /*
1221                  * Sanity-check schain's pmp and finish initialization.
1222                  * Any chain belonging to the super-root topology should
1223                  * have a NULL pmp (not even set to spmp).
1224                  */
1225                 ripdata = &hammer2_chain_rdata(schain)->ipdata;
1226                 KKASSERT(schain->pmp == NULL);
1227                 spmp->pfs_clid = ripdata->meta.pfs_clid;
1228
1229                 /*
1230                  * Replace the dummy spmp->iroot with a real one.  It's
1231                  * easier to just do a wholesale replacement than to try
1232                  * to update the chain and fixup the iroot fields.
1233                  *
1234                  * The returned inode is locked with the supplied cluster.
1235                  */
1236                 cluster = hammer2_cluster_from_chain(schain);
1237                 hammer2_inode_drop(spmp->iroot);
1238                 spmp->iroot = NULL;
1239                 spmp->iroot = hammer2_inode_get(spmp, NULL, cluster, -1);
1240                 spmp->spmp_hmp = hmp;
1241                 spmp->pfs_types[0] = ripdata->meta.pfs_type;
1242                 spmp->pfs_hmps[0] = hmp;
1243                 hammer2_inode_ref(spmp->iroot);
1244                 hammer2_inode_unlock(spmp->iroot);
1245                 hammer2_cluster_unlock(cluster);
1246                 hammer2_cluster_drop(cluster);
1247                 schain = NULL;
1248                 /* leave spmp->iroot with one ref */
1249
1250                 if ((mp->mnt_flag & MNT_RDONLY) == 0) {
1251                         error = hammer2_recovery(hmp);
1252                         /* XXX do something with error */
1253                 }
1254                 hammer2_update_pmps(hmp);
1255                 hammer2_iocom_init(hmp);
1256                 hammer2_bulkfree_init(hmp);
1257
1258                 /*
1259                  * Ref the cluster management messaging descriptor.  The mount
1260                  * program deals with the other end of the communications pipe.
1261                  *
1262                  * Root mounts typically do not supply one.
1263                  */
1264                 if (info.cluster_fd >= 0) {
1265                         fp = holdfp(curproc->p_fd, info.cluster_fd, -1);
1266                         if (fp) {
1267                                 hammer2_cluster_reconnect(hmp, fp);
1268                         } else {
1269                                 kprintf("hammer2_mount: bad cluster_fd!\n");
1270                         }
1271                 }
1272         } else {
1273                 spmp = hmp->spmp;
1274                 if (info.hflags & HMNT2_DEVFLAGS) {
1275                         kprintf("hammer2: Warning: mount flags pertaining "
1276                                 "to the whole device may only be specified "
1277                                 "on the first mount of the device: %08x\n",
1278                                 info.hflags & HMNT2_DEVFLAGS);
1279                 }
1280         }
1281
1282         /*
1283          * Force local mount (disassociate all PFSs from their clusters).
1284          * Used primarily for debugging.
1285          */
1286         force_local = (hmp->hflags & HMNT2_LOCAL) ? hmp : NULL;
1287
1288         /*
1289          * Lookup the mount point under the media-localized super-root.
1290          * Scanning hammer2_pfslist doesn't help us because it represents
1291          * PFS cluster ids which can aggregate several named PFSs together.
1292          *
1293          * cluster->pmp will incorrectly point to spmp and must be fixed
1294          * up later on.
1295          */
1296         hammer2_inode_lock(spmp->iroot, 0);
1297         parent = hammer2_inode_chain(spmp->iroot, 0, HAMMER2_RESOLVE_ALWAYS);
1298         lhc = hammer2_dirhash(label, strlen(label));
1299         chain = hammer2_chain_lookup(&parent, &key_next,
1300                                      lhc, lhc + HAMMER2_DIRHASH_LOMASK,
1301                                      &error, 0);
1302         while (chain) {
1303                 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE &&
1304                     strcmp(label, chain->data->ipdata.filename) == 0) {
1305                         break;
1306                 }
1307                 chain = hammer2_chain_next(&parent, chain, &key_next,
1308                                             key_next,
1309                                             lhc + HAMMER2_DIRHASH_LOMASK,
1310                                             &error, 0);
1311         }
1312         if (parent) {
1313                 hammer2_chain_unlock(parent);
1314                 hammer2_chain_drop(parent);
1315         }
1316         hammer2_inode_unlock(spmp->iroot);
1317
1318         /*
1319          * PFS could not be found?
1320          */
1321         if (chain == NULL) {
1322                 if (error)
1323                         kprintf("hammer2_mount: PFS label I/O error\n");
1324                 else
1325                         kprintf("hammer2_mount: PFS label not found\n");
1326                 hammer2_unmount_helper(mp, NULL, hmp);
1327                 lockmgr(&hammer2_mntlk, LK_RELEASE);
1328                 hammer2_vfs_unmount(mp, MNT_FORCE);
1329
1330                 return EINVAL;
1331         }
1332
1333         /*
1334          * Acquire the pmp structure (it should have already been allocated
1335          * via hammer2_update_pmps() so do not pass cluster in to add to
1336          * available chains).
1337          *
1338          * Check if the cluster has already been mounted.  A cluster can
1339          * only be mounted once, use null mounts to mount additional copies.
1340          */
1341         if (chain->error) {
1342                 kprintf("hammer2_mount: PFS label I/O error\n");
1343         } else {
1344                 ripdata = &chain->data->ipdata;
1345                 bref = chain->bref;
1346                 pmp = hammer2_pfsalloc(NULL, ripdata,
1347                                        bref.modify_tid, force_local);
1348         }
1349         hammer2_chain_unlock(chain);
1350         hammer2_chain_drop(chain);
1351
1352         /*
1353          * Finish the mount
1354          */
1355         kprintf("hammer2_mount hmp=%p pmp=%p\n", hmp, pmp);
1356
1357         if (pmp->mp) {
1358                 kprintf("hammer2_mount: PFS already mounted!\n");
1359                 hammer2_unmount_helper(mp, NULL, hmp);
1360                 lockmgr(&hammer2_mntlk, LK_RELEASE);
1361                 hammer2_vfs_unmount(mp, MNT_FORCE);
1362
1363                 return EBUSY;
1364         }
1365
1366         pmp->hflags = info.hflags;
1367         mp->mnt_flag |= MNT_LOCAL;
1368         mp->mnt_kern_flag |= MNTK_ALL_MPSAFE;   /* all entry pts are SMP */
1369         mp->mnt_kern_flag |= MNTK_THR_SYNC;     /* new vsyncscan semantics */
1370  
1371         /*
1372          * required mount structure initializations
1373          */
1374         mp->mnt_stat.f_iosize = HAMMER2_PBUFSIZE;
1375         mp->mnt_stat.f_bsize = HAMMER2_PBUFSIZE;
1376  
1377         mp->mnt_vstat.f_frsize = HAMMER2_PBUFSIZE;
1378         mp->mnt_vstat.f_bsize = HAMMER2_PBUFSIZE;
1379  
1380         /*
1381          * Optional fields
1382          */
1383         mp->mnt_iosize_max = MAXPHYS;
1384
1385         /*
1386          * Connect up mount pointers.
1387          */
1388         hammer2_mount_helper(mp, pmp);
1389
1390         lockmgr(&hammer2_mntlk, LK_RELEASE);
1391
1392         /*
1393          * Finish setup
1394          */
1395         vfs_getnewfsid(mp);
1396         vfs_add_vnodeops(mp, &hammer2_vnode_vops, &mp->mnt_vn_norm_ops);
1397         vfs_add_vnodeops(mp, &hammer2_spec_vops, &mp->mnt_vn_spec_ops);
1398         vfs_add_vnodeops(mp, &hammer2_fifo_vops, &mp->mnt_vn_fifo_ops);
1399
1400         if (path) {
1401                 copyinstr(info.volume, mp->mnt_stat.f_mntfromname,
1402                           MNAMELEN - 1, &size);
1403                 bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
1404         } /* else root mount, already in there */
1405
1406         bzero(mp->mnt_stat.f_mntonname, sizeof(mp->mnt_stat.f_mntonname));
1407         if (path) {
1408                 copyinstr(path, mp->mnt_stat.f_mntonname,
1409                           sizeof(mp->mnt_stat.f_mntonname) - 1,
1410                           &size);
1411         } else {
1412                 /* root mount */
1413                 mp->mnt_stat.f_mntonname[0] = '/';
1414         }
1415
1416         /*
1417          * Initial statfs to prime mnt_stat.
1418          */
1419         hammer2_vfs_statfs(mp, &mp->mnt_stat, cred);
1420         
1421         return 0;
1422 }
1423
1424 /*
1425  * Scan PFSs under the super-root and create hammer2_pfs structures.
1426  */
1427 static
1428 void
1429 hammer2_update_pmps(hammer2_dev_t *hmp)
1430 {
1431         const hammer2_inode_data_t *ripdata;
1432         hammer2_chain_t *parent;
1433         hammer2_chain_t *chain;
1434         hammer2_blockref_t bref;
1435         hammer2_dev_t *force_local;
1436         hammer2_pfs_t *spmp;
1437         hammer2_pfs_t *pmp;
1438         hammer2_key_t key_next;
1439         int error;
1440
1441         /*
1442          * Force local mount (disassociate all PFSs from their clusters).
1443          * Used primarily for debugging.
1444          */
1445         force_local = (hmp->hflags & HMNT2_LOCAL) ? hmp : NULL;
1446
1447         /*
1448          * Lookup mount point under the media-localized super-root.
1449          *
1450          * cluster->pmp will incorrectly point to spmp and must be fixed
1451          * up later on.
1452          */
1453         spmp = hmp->spmp;
1454         hammer2_inode_lock(spmp->iroot, 0);
1455         parent = hammer2_inode_chain(spmp->iroot, 0, HAMMER2_RESOLVE_ALWAYS);
1456         chain = hammer2_chain_lookup(&parent, &key_next,
1457                                          HAMMER2_KEY_MIN, HAMMER2_KEY_MAX,
1458                                          &error, 0);
1459         while (chain) {
1460                 if (chain->bref.type != HAMMER2_BREF_TYPE_INODE)
1461                         continue;
1462                 if (chain->error) {
1463                         kprintf("I/O error scanning PFS labels\n");
1464                 } else {
1465                         ripdata = &chain->data->ipdata;
1466                         bref = chain->bref;
1467                         kprintf("ADD LOCAL PFS: %s\n", ripdata->filename);
1468
1469                         pmp = hammer2_pfsalloc(chain, ripdata,
1470                                                bref.modify_tid, force_local);
1471                 }
1472                 chain = hammer2_chain_next(&parent, chain, &key_next,
1473                                            key_next, HAMMER2_KEY_MAX,
1474                                            &error, 0);
1475         }
1476         if (parent) {
1477                 hammer2_chain_unlock(parent);
1478                 hammer2_chain_drop(parent);
1479         }
1480         hammer2_inode_unlock(spmp->iroot);
1481 }
1482
1483 static
1484 int
1485 hammer2_remount(hammer2_dev_t *hmp, struct mount *mp, char *path __unused,
1486                 struct vnode *devvp, struct ucred *cred)
1487 {
1488         int error;
1489
1490         if (hmp->ronly && (mp->mnt_kern_flag & MNTK_WANTRDWR)) {
1491                 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
1492                 VOP_OPEN(devvp, FREAD | FWRITE, FSCRED, NULL);
1493                 vn_unlock(devvp);
1494                 error = hammer2_recovery(hmp);
1495                 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
1496                 if (error == 0) {
1497                         VOP_CLOSE(devvp, FREAD, NULL);
1498                         hmp->ronly = 0;
1499                 } else {
1500                         VOP_CLOSE(devvp, FREAD | FWRITE, NULL);
1501                 }
1502                 vn_unlock(devvp);
1503         } else {
1504                 error = 0;
1505         }
1506         return error;
1507 }
1508
1509 static
1510 int
1511 hammer2_vfs_unmount(struct mount *mp, int mntflags)
1512 {
1513         hammer2_pfs_t *pmp;
1514         int flags;
1515         int error = 0;
1516
1517         pmp = MPTOPMP(mp);
1518
1519         if (pmp == NULL)
1520                 return(0);
1521
1522         lockmgr(&hammer2_mntlk, LK_EXCLUSIVE);
1523
1524         /*
1525          * If mount initialization proceeded far enough we must flush
1526          * its vnodes and sync the underlying mount points.  Three syncs
1527          * are required to fully flush the filesystem (freemap updates lag
1528          * by one flush, and one extra for safety).
1529          */
1530         if (mntflags & MNT_FORCE)
1531                 flags = FORCECLOSE;
1532         else
1533                 flags = 0;
1534         if (pmp->iroot) {
1535                 error = vflush(mp, 0, flags);
1536                 if (error)
1537                         goto failed;
1538                 hammer2_vfs_sync(mp, MNT_WAIT);
1539                 hammer2_vfs_sync(mp, MNT_WAIT);
1540                 hammer2_vfs_sync(mp, MNT_WAIT);
1541         }
1542
1543         /*
1544          * Cleanup the frontend support XOPS threads
1545          */
1546         hammer2_xop_helper_cleanup(pmp);
1547
1548         if (pmp->mp)
1549                 hammer2_unmount_helper(mp, pmp, NULL);
1550
1551         error = 0;
1552 failed:
1553         lockmgr(&hammer2_mntlk, LK_RELEASE);
1554
1555         return (error);
1556 }
1557
1558 /*
1559  * Mount helper, hook the system mount into our PFS.
1560  * The mount lock is held.
1561  *
1562  * We must bump the mount_count on related devices for any
1563  * mounted PFSs.
1564  */
1565 static
1566 void
1567 hammer2_mount_helper(struct mount *mp, hammer2_pfs_t *pmp)
1568 {
1569         hammer2_cluster_t *cluster;
1570         hammer2_chain_t *rchain;
1571         int i;
1572
1573         mp->mnt_data = (qaddr_t)pmp;
1574         pmp->mp = mp;
1575
1576         /*
1577          * After pmp->mp is set we have to adjust hmp->mount_count.
1578          */
1579         cluster = &pmp->iroot->cluster;
1580         for (i = 0; i < cluster->nchains; ++i) {
1581                 rchain = cluster->array[i].chain;
1582                 if (rchain == NULL)
1583                         continue;
1584                 ++rchain->hmp->mount_count;
1585                 kprintf("hammer2_mount hmp=%p ++mount_count=%d\n",
1586                         rchain->hmp, rchain->hmp->mount_count);
1587         }
1588
1589         /*
1590          * Create missing Xop threads
1591          */
1592         hammer2_xop_helper_create(pmp);
1593 }
1594
1595 /*
1596  * Mount helper, unhook the system mount from our PFS.
1597  * The mount lock is held.
1598  *
1599  * If hmp is supplied a mount responsible for being the first to open
1600  * the block device failed and the block device and all PFSs using the
1601  * block device must be cleaned up.
1602  *
1603  * If pmp is supplied multiple devices might be backing the PFS and each
1604  * must be disconnected.  This might not be the last PFS using some of the
1605  * underlying devices.  Also, we have to adjust our hmp->mount_count
1606  * accounting for the devices backing the pmp which is now undergoing an
1607  * unmount.
1608  */
1609 static
1610 void
1611 hammer2_unmount_helper(struct mount *mp, hammer2_pfs_t *pmp, hammer2_dev_t *hmp)
1612 {
1613         hammer2_cluster_t *cluster;
1614         hammer2_chain_t *rchain;
1615         struct vnode *devvp;
1616         int dumpcnt;
1617         int ronly;
1618         int i;
1619
1620         /*
1621          * If no device supplied this is a high-level unmount and we have to
1622          * to disconnect the mount, adjust mount_count, and locate devices
1623          * that might now have no mounts.
1624          */
1625         if (pmp) {
1626                 KKASSERT(hmp == NULL);
1627                 KKASSERT((void *)(intptr_t)mp->mnt_data == pmp);
1628                 pmp->mp = NULL;
1629                 mp->mnt_data = NULL;
1630
1631                 /*
1632                  * After pmp->mp is cleared we have to account for
1633                  * mount_count.
1634                  */
1635                 cluster = &pmp->iroot->cluster;
1636                 for (i = 0; i < cluster->nchains; ++i) {
1637                         rchain = cluster->array[i].chain;
1638                         if (rchain == NULL)
1639                                 continue;
1640                         --rchain->hmp->mount_count;
1641                         kprintf("hammer2_unmount hmp=%p --mount_count=%d\n",
1642                                 rchain->hmp, rchain->hmp->mount_count);
1643                         /* scrapping hmp now may invalidate the pmp */
1644                 }
1645 again:
1646                 TAILQ_FOREACH(hmp, &hammer2_mntlist, mntentry) {
1647                         if (hmp->mount_count == 0) {
1648                                 hammer2_unmount_helper(NULL, NULL, hmp);
1649                                 goto again;
1650                         }
1651                 }
1652                 return;
1653         }
1654
1655         /*
1656          * Try to terminate the block device.  We can't terminate it if
1657          * there are still PFSs referencing it.
1658          */
1659         kprintf("hammer2_unmount hmp=%p mount_count=%d\n",
1660                 hmp, hmp->mount_count);
1661         if (hmp->mount_count)
1662                 return;
1663
1664         hammer2_bulkfree_uninit(hmp);
1665         hammer2_pfsfree_scan(hmp);
1666         hammer2_dev_exlock(hmp);        /* XXX order */
1667
1668         /*
1669          * Cycle the volume data lock as a safety (probably not needed any
1670          * more).  To ensure everything is out we need to flush at least
1671          * three times.  (1) The running of the sideq can dirty the
1672          * filesystem, (2) A normal flush can dirty the freemap, and
1673          * (3) ensure that the freemap is fully synchronized.
1674          *
1675          * The next mount's recovery scan can clean everything up but we want
1676          * to leave the filesystem in a 100% clean state on a normal unmount.
1677          */
1678 #if 0
1679         hammer2_voldata_lock(hmp);
1680         hammer2_voldata_unlock(hmp);
1681 #endif
1682         hammer2_iocom_uninit(hmp);
1683
1684         if ((hmp->vchain.flags | hmp->fchain.flags) &
1685             HAMMER2_CHAIN_FLUSH_MASK) {
1686                 kprintf("hammer2_unmount: chains left over "
1687                         "after final sync\n");
1688                 kprintf("    vchain %08x\n", hmp->vchain.flags);
1689                 kprintf("    fchain %08x\n", hmp->fchain.flags);
1690
1691                 if (hammer2_debug & 0x0010)
1692                         Debugger("entered debugger");
1693         }
1694
1695         KKASSERT(hmp->spmp == NULL);
1696
1697         /*
1698          * Finish up with the device vnode
1699          */
1700         if ((devvp = hmp->devvp) != NULL) {
1701                 ronly = hmp->ronly;
1702                 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
1703                 kprintf("hammer2_unmount(A): devvp %s rbdirty %p ronly=%d\n",
1704                         hmp->devrepname, RB_ROOT(&devvp->v_rbdirty_tree),
1705                         ronly);
1706                 vinvalbuf(devvp, (ronly ? 0 : V_SAVE), 0, 0);
1707                 kprintf("hammer2_unmount(B): devvp %s rbdirty %p\n",
1708                         hmp->devrepname, RB_ROOT(&devvp->v_rbdirty_tree));
1709                 hmp->devvp = NULL;
1710                 VOP_CLOSE(devvp, (ronly ? FREAD : FREAD|FWRITE), NULL);
1711                 vn_unlock(devvp);
1712                 vrele(devvp);
1713                 devvp = NULL;
1714         }
1715
1716         /*
1717          * Clear vchain/fchain flags that might prevent final cleanup
1718          * of these chains.
1719          */
1720         if (hmp->vchain.flags & HAMMER2_CHAIN_MODIFIED) {
1721                 atomic_add_long(&hammer2_count_modified_chains, -1);
1722                 atomic_clear_int(&hmp->vchain.flags, HAMMER2_CHAIN_MODIFIED);
1723                 hammer2_pfs_memory_wakeup(hmp->vchain.pmp);
1724         }
1725         if (hmp->vchain.flags & HAMMER2_CHAIN_UPDATE) {
1726                 atomic_clear_int(&hmp->vchain.flags, HAMMER2_CHAIN_UPDATE);
1727         }
1728
1729         if (hmp->fchain.flags & HAMMER2_CHAIN_MODIFIED) {
1730                 atomic_add_long(&hammer2_count_modified_chains, -1);
1731                 atomic_clear_int(&hmp->fchain.flags, HAMMER2_CHAIN_MODIFIED);
1732                 hammer2_pfs_memory_wakeup(hmp->fchain.pmp);
1733         }
1734         if (hmp->fchain.flags & HAMMER2_CHAIN_UPDATE) {
1735                 atomic_clear_int(&hmp->fchain.flags, HAMMER2_CHAIN_UPDATE);
1736         }
1737
1738         /*
1739          * Final drop of embedded freemap root chain to
1740          * clean up fchain.core (fchain structure is not
1741          * flagged ALLOCATED so it is cleaned out and then
1742          * left to rot).
1743          */
1744         hammer2_chain_drop(&hmp->fchain);
1745
1746         /*
1747          * Final drop of embedded volume root chain to clean
1748          * up vchain.core (vchain structure is not flagged
1749          * ALLOCATED so it is cleaned out and then left to
1750          * rot).
1751          */
1752         dumpcnt = 50;
1753         hammer2_dump_chain(&hmp->vchain, 0, &dumpcnt, 'v');
1754         dumpcnt = 50;
1755         hammer2_dump_chain(&hmp->fchain, 0, &dumpcnt, 'f');
1756         hammer2_dev_unlock(hmp);
1757         hammer2_chain_drop(&hmp->vchain);
1758
1759         hammer2_io_cleanup(hmp, &hmp->iotree);
1760         if (hmp->iofree_count) {
1761                 kprintf("io_cleanup: %d I/O's left hanging\n",
1762                         hmp->iofree_count);
1763         }
1764
1765         TAILQ_REMOVE(&hammer2_mntlist, hmp, mntentry);
1766         kmalloc_destroy(&hmp->mchain);
1767         kfree(hmp, M_HAMMER2);
1768 }
1769
1770 int
1771 hammer2_vfs_vget(struct mount *mp, struct vnode *dvp,
1772                  ino_t ino, struct vnode **vpp)
1773 {
1774         hammer2_xop_lookup_t *xop;
1775         hammer2_pfs_t *pmp;
1776         hammer2_inode_t *ip;
1777         hammer2_tid_t inum;
1778         int error;
1779
1780         inum = (hammer2_tid_t)ino & HAMMER2_DIRHASH_USERMSK;
1781
1782         error = 0;
1783         pmp = MPTOPMP(mp);
1784
1785         /*
1786          * Easy if we already have it cached
1787          */
1788         ip = hammer2_inode_lookup(pmp, inum);
1789         if (ip) {
1790                 hammer2_inode_lock(ip, HAMMER2_RESOLVE_SHARED);
1791                 *vpp = hammer2_igetv(ip, &error);
1792                 hammer2_inode_unlock(ip);
1793                 hammer2_inode_drop(ip);         /* from lookup */
1794
1795                 return error;
1796         }
1797
1798         /*
1799          * Otherwise we have to find the inode
1800          */
1801         xop = hammer2_xop_alloc(pmp->iroot, 0);
1802         xop->lhc = inum;
1803         hammer2_xop_start(&xop->head, hammer2_xop_lookup);
1804         error = hammer2_xop_collect(&xop->head, 0);
1805
1806         if (error == 0) {
1807                 if (hammer2_cluster_rdata(&xop->head.cluster) == NULL) {
1808                         kprintf("vget: no collect error but also no rdata\n");
1809                         kprintf("xop %p\n", xop);
1810                         while ((hammer2_debug & 0x80000) == 0) {
1811                                 tsleep(xop, PCATCH, "wait", hz * 10);
1812                         }
1813                         ip = NULL;
1814                 } else {
1815                         ip = hammer2_inode_get(pmp, NULL, &xop->head.cluster, -1);
1816                 }
1817         }
1818         hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP);
1819
1820         if (ip) {
1821                 *vpp = hammer2_igetv(ip, &error);
1822                 hammer2_inode_unlock(ip);
1823         } else {
1824                 *vpp = NULL;
1825                 error = ENOENT;
1826         }
1827         return (error);
1828 }
1829
1830 static
1831 int
1832 hammer2_vfs_root(struct mount *mp, struct vnode **vpp)
1833 {
1834         hammer2_pfs_t *pmp;
1835         struct vnode *vp;
1836         int error;
1837
1838         pmp = MPTOPMP(mp);
1839         if (pmp->iroot == NULL) {
1840                 *vpp = NULL;
1841                 return EINVAL;
1842         }
1843
1844         error = 0;
1845         hammer2_inode_lock(pmp->iroot, HAMMER2_RESOLVE_SHARED);
1846
1847         while (pmp->inode_tid == 0) {
1848                 hammer2_xop_ipcluster_t *xop;
1849                 hammer2_inode_meta_t *meta;
1850
1851                 xop = hammer2_xop_alloc(pmp->iroot, HAMMER2_XOP_MODIFYING);
1852                 hammer2_xop_start(&xop->head, hammer2_xop_ipcluster);
1853                 error = hammer2_xop_collect(&xop->head, 0);
1854
1855                 if (error == 0) {
1856                         meta = &xop->head.cluster.focus->data->ipdata.meta;
1857                         pmp->iroot->meta = *meta;
1858                         pmp->inode_tid = meta->pfs_inum + 1;
1859                         if (pmp->inode_tid < HAMMER2_INODE_START)
1860                                 pmp->inode_tid = HAMMER2_INODE_START;
1861                         pmp->modify_tid =
1862                                 xop->head.cluster.focus->bref.modify_tid + 1;
1863                         kprintf("PFS: Starting inode %jd\n",
1864                                 (intmax_t)pmp->inode_tid);
1865                         kprintf("PMP focus good set nextino=%ld mod=%016jx\n",
1866                                 pmp->inode_tid, pmp->modify_tid);
1867                         wakeup(&pmp->iroot);
1868
1869                         hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP);
1870
1871                         /*
1872                          * Prime the mount info.
1873                          */
1874                         hammer2_vfs_statfs(mp, &mp->mnt_stat, NULL);
1875                         break;
1876                 }
1877
1878                 /*
1879                  * Loop, try again
1880                  */
1881                 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP);
1882                 hammer2_inode_unlock(pmp->iroot);
1883                 error = tsleep(&pmp->iroot, PCATCH, "h2root", hz);
1884                 hammer2_inode_lock(pmp->iroot, HAMMER2_RESOLVE_SHARED);
1885                 if (error == EINTR)
1886                         break;
1887         }
1888
1889         if (error) {
1890                 hammer2_inode_unlock(pmp->iroot);
1891                 *vpp = NULL;
1892         } else {
1893                 vp = hammer2_igetv(pmp->iroot, &error);
1894                 hammer2_inode_unlock(pmp->iroot);
1895                 *vpp = vp;
1896         }
1897
1898         return (error);
1899 }
1900
1901 /*
1902  * Filesystem status
1903  *
1904  * XXX incorporate ipdata->meta.inode_quota and data_quota
1905  */
1906 static
1907 int
1908 hammer2_vfs_statfs(struct mount *mp, struct statfs *sbp, struct ucred *cred)
1909 {
1910         hammer2_pfs_t *pmp;
1911         hammer2_dev_t *hmp;
1912         hammer2_blockref_t bref;
1913         int i;
1914
1915         /*
1916          * NOTE: iroot might not have validated the cluster yet.
1917          */
1918         pmp = MPTOPMP(mp);
1919
1920         mp->mnt_stat.f_files = 0;
1921         mp->mnt_stat.f_ffree = 0;
1922         mp->mnt_stat.f_blocks = 0;
1923         mp->mnt_stat.f_bfree = 0;
1924         mp->mnt_stat.f_bavail = 0;
1925
1926         for (i = 0; i < pmp->iroot->cluster.nchains; ++i) {
1927                 hmp = pmp->pfs_hmps[i];
1928                 if (hmp == NULL)
1929                         continue;
1930                 if (pmp->iroot->cluster.array[i].chain)
1931                         bref = pmp->iroot->cluster.array[i].chain->bref;
1932                 else
1933                         bzero(&bref, sizeof(bref));
1934
1935                 mp->mnt_stat.f_files = bref.embed.stats.inode_count;
1936                 mp->mnt_stat.f_ffree = 0;
1937                 mp->mnt_stat.f_blocks = hmp->voldata.allocator_size /
1938                                         mp->mnt_vstat.f_bsize;
1939                 mp->mnt_stat.f_bfree = hmp->voldata.allocator_free /
1940                                         mp->mnt_vstat.f_bsize;
1941                 mp->mnt_stat.f_bavail = mp->mnt_stat.f_bfree;
1942
1943                 *sbp = mp->mnt_stat;
1944         }
1945         return (0);
1946 }
1947
1948 static
1949 int
1950 hammer2_vfs_statvfs(struct mount *mp, struct statvfs *sbp, struct ucred *cred)
1951 {
1952         hammer2_pfs_t *pmp;
1953         hammer2_dev_t *hmp;
1954         hammer2_blockref_t bref;
1955         int i;
1956
1957         /*
1958          * NOTE: iroot might not have validated the cluster yet.
1959          */
1960         pmp = MPTOPMP(mp);
1961
1962         mp->mnt_vstat.f_bsize = 0;
1963         mp->mnt_vstat.f_files = 0;
1964         mp->mnt_vstat.f_ffree = 0;
1965         mp->mnt_vstat.f_blocks = 0;
1966         mp->mnt_vstat.f_bfree = 0;
1967         mp->mnt_vstat.f_bavail = 0;
1968
1969         for (i = 0; i < pmp->iroot->cluster.nchains; ++i) {
1970                 hmp = pmp->pfs_hmps[i];
1971                 if (hmp == NULL)
1972                         continue;
1973                 if (pmp->iroot->cluster.array[i].chain)
1974                         bref = pmp->iroot->cluster.array[i].chain->bref;
1975                 else
1976                         bzero(&bref, sizeof(bref));
1977
1978                 mp->mnt_vstat.f_bsize = HAMMER2_PBUFSIZE;
1979                 mp->mnt_vstat.f_files = bref.embed.stats.inode_count;
1980                 mp->mnt_vstat.f_ffree = 0;
1981                 mp->mnt_vstat.f_blocks = hmp->voldata.allocator_size /
1982                                         mp->mnt_vstat.f_bsize;
1983                 mp->mnt_vstat.f_bfree = hmp->voldata.allocator_free /
1984                                         mp->mnt_vstat.f_bsize;
1985                 mp->mnt_vstat.f_bavail = mp->mnt_vstat.f_bfree;
1986
1987                 *sbp = mp->mnt_vstat;
1988         }
1989         return (0);
1990 }
1991
1992 /*
1993  * Mount-time recovery (RW mounts)
1994  *
1995  * Updates to the free block table are allowed to lag flushes by one
1996  * transaction.  In case of a crash, then on a fresh mount we must do an
1997  * incremental scan of the last committed transaction id and make sure that
1998  * all related blocks have been marked allocated.
1999  *
2000  * The super-root topology and each PFS has its own transaction id domain,
2001  * so we must track PFS boundary transitions.
2002  */
2003 struct hammer2_recovery_elm {
2004         TAILQ_ENTRY(hammer2_recovery_elm) entry;
2005         hammer2_chain_t *chain;
2006         hammer2_tid_t sync_tid;
2007 };
2008
2009 TAILQ_HEAD(hammer2_recovery_list, hammer2_recovery_elm);
2010
2011 struct hammer2_recovery_info {
2012         struct hammer2_recovery_list list;
2013         hammer2_tid_t   mtid;
2014         int     depth;
2015 };
2016
2017 static int hammer2_recovery_scan(hammer2_dev_t *hmp,
2018                         hammer2_chain_t *parent,
2019                         struct hammer2_recovery_info *info,
2020                         hammer2_tid_t sync_tid);
2021
2022 #define HAMMER2_RECOVERY_MAXDEPTH       10
2023
2024 static
2025 int
2026 hammer2_recovery(hammer2_dev_t *hmp)
2027 {
2028         struct hammer2_recovery_info info;
2029         struct hammer2_recovery_elm *elm;
2030         hammer2_chain_t *parent;
2031         hammer2_tid_t sync_tid;
2032         hammer2_tid_t mirror_tid;
2033         int error;
2034
2035         hammer2_trans_init(hmp->spmp, 0);
2036
2037         sync_tid = hmp->voldata.freemap_tid;
2038         mirror_tid = hmp->voldata.mirror_tid;
2039
2040         kprintf("hammer2 mount \"%s\": ", hmp->devrepname);
2041         if (sync_tid >= mirror_tid) {
2042                 kprintf(" no recovery needed\n");
2043         } else {
2044                 kprintf(" freemap recovery %016jx-%016jx\n",
2045                         sync_tid + 1, mirror_tid);
2046         }
2047
2048         TAILQ_INIT(&info.list);
2049         info.depth = 0;
2050         parent = hammer2_chain_lookup_init(&hmp->vchain, 0);
2051         error = hammer2_recovery_scan(hmp, parent, &info, sync_tid);
2052         hammer2_chain_lookup_done(parent);
2053
2054         while ((elm = TAILQ_FIRST(&info.list)) != NULL) {
2055                 TAILQ_REMOVE(&info.list, elm, entry);
2056                 parent = elm->chain;
2057                 sync_tid = elm->sync_tid;
2058                 kfree(elm, M_HAMMER2);
2059
2060                 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
2061                 error |= hammer2_recovery_scan(hmp, parent, &info,
2062                                               hmp->voldata.freemap_tid);
2063                 hammer2_chain_unlock(parent);
2064                 hammer2_chain_drop(parent);     /* drop elm->chain ref */
2065         }
2066         hammer2_trans_done(hmp->spmp);
2067
2068         return error;
2069 }
2070
2071 static
2072 int
2073 hammer2_recovery_scan(hammer2_dev_t *hmp, hammer2_chain_t *parent,
2074                       struct hammer2_recovery_info *info,
2075                       hammer2_tid_t sync_tid)
2076 {
2077         const hammer2_inode_data_t *ripdata;
2078         hammer2_chain_t *chain;
2079         hammer2_blockref_t bref;
2080         int tmp_error;
2081         int rup_error;
2082         int error;
2083         int first;
2084
2085         /*
2086          * Adjust freemap to ensure that the block(s) are marked allocated.
2087          */
2088         if (parent->bref.type != HAMMER2_BREF_TYPE_VOLUME) {
2089                 hammer2_freemap_adjust(hmp, &parent->bref,
2090                                        HAMMER2_FREEMAP_DORECOVER);
2091         }
2092
2093         /*
2094          * Check type for recursive scan
2095          */
2096         switch(parent->bref.type) {
2097         case HAMMER2_BREF_TYPE_VOLUME:
2098                 /* data already instantiated */
2099                 break;
2100         case HAMMER2_BREF_TYPE_INODE:
2101                 /*
2102                  * Must instantiate data for DIRECTDATA test and also
2103                  * for recursion.
2104                  */
2105                 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
2106                 ripdata = &hammer2_chain_rdata(parent)->ipdata;
2107                 if (ripdata->meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA) {
2108                         /* not applicable to recovery scan */
2109                         hammer2_chain_unlock(parent);
2110                         return 0;
2111                 }
2112                 hammer2_chain_unlock(parent);
2113                 break;
2114         case HAMMER2_BREF_TYPE_INDIRECT:
2115                 /*
2116                  * Must instantiate data for recursion
2117                  */
2118                 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
2119                 hammer2_chain_unlock(parent);
2120                 break;
2121         case HAMMER2_BREF_TYPE_DIRENT:
2122         case HAMMER2_BREF_TYPE_DATA:
2123         case HAMMER2_BREF_TYPE_FREEMAP:
2124         case HAMMER2_BREF_TYPE_FREEMAP_NODE:
2125         case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
2126                 /* not applicable to recovery scan */
2127                 return 0;
2128                 break;
2129         default:
2130                 return HAMMER2_ERROR_BADBREF;
2131         }
2132
2133         /*
2134          * Defer operation if depth limit reached or if we are crossing a
2135          * PFS boundary.
2136          */
2137         if (info->depth >= HAMMER2_RECOVERY_MAXDEPTH) {
2138                 struct hammer2_recovery_elm *elm;
2139
2140                 elm = kmalloc(sizeof(*elm), M_HAMMER2, M_ZERO | M_WAITOK);
2141                 elm->chain = parent;
2142                 elm->sync_tid = sync_tid;
2143                 hammer2_chain_ref(parent);
2144                 TAILQ_INSERT_TAIL(&info->list, elm, entry);
2145                 /* unlocked by caller */
2146
2147                 return(0);
2148         }
2149
2150
2151         /*
2152          * Recursive scan of the last flushed transaction only.  We are
2153          * doing this without pmp assignments so don't leave the chains
2154          * hanging around after we are done with them.
2155          *
2156          * error        Cumulative error this level only
2157          * rup_error    Cumulative error for recursion
2158          * tmp_error    Specific non-cumulative recursion error
2159          */
2160         chain = NULL;
2161         first = 1;
2162         rup_error = 0;
2163         error = 0;
2164
2165         for (;;) {
2166                 error |= hammer2_chain_scan(parent, &chain, &bref,
2167                                             &first,
2168                                             HAMMER2_LOOKUP_NODATA);
2169
2170                 /*
2171                  * Problem during scan or EOF
2172                  */
2173                 if (error)
2174                         break;
2175
2176                 /*
2177                  * If this is a leaf
2178                  */
2179                 if (chain == NULL) {
2180                         if (bref.mirror_tid > sync_tid) {
2181                                 hammer2_freemap_adjust(hmp, &bref,
2182                                                      HAMMER2_FREEMAP_DORECOVER);
2183                         }
2184                         continue;
2185                 }
2186
2187                 /*
2188                  * This may or may not be a recursive node.
2189                  */
2190                 atomic_set_int(&chain->flags, HAMMER2_CHAIN_RELEASE);
2191                 if (bref.mirror_tid > sync_tid) {
2192                         ++info->depth;
2193                         tmp_error = hammer2_recovery_scan(hmp, chain,
2194                                                            info, sync_tid);
2195                         --info->depth;
2196                 } else {
2197                         tmp_error = 0;
2198                 }
2199
2200                 /*
2201                  * Flush the recovery at the PFS boundary to stage it for
2202                  * the final flush of the super-root topology.
2203                  */
2204                 if (tmp_error == 0 &&
2205                     (bref.flags & HAMMER2_BREF_FLAG_PFSROOT) &&
2206                     (chain->flags & HAMMER2_CHAIN_ONFLUSH)) {
2207                         hammer2_flush(chain, HAMMER2_FLUSH_TOP);
2208                 }
2209                 rup_error |= tmp_error;
2210         }
2211         return ((error | rup_error) & ~HAMMER2_ERROR_EOF);
2212 }
2213
2214 /*
2215  * Sync a mount point; this is called on a per-mount basis from the
2216  * filesystem syncer process periodically and whenever a user issues
2217  * a sync.
2218  */
2219 int
2220 hammer2_vfs_sync(struct mount *mp, int waitfor)
2221 {
2222         hammer2_xop_flush_t *xop;
2223         struct hammer2_sync_info info;
2224         hammer2_inode_t *iroot;
2225         hammer2_pfs_t *pmp;
2226         int flags;
2227         int error;
2228
2229         pmp = MPTOPMP(mp);
2230         iroot = pmp->iroot;
2231         KKASSERT(iroot);
2232         KKASSERT(iroot->pmp == pmp);
2233
2234         /*
2235          * We can't acquire locks on existing vnodes while in a transaction
2236          * without risking a deadlock.  This assumes that vfsync() can be
2237          * called without the vnode locked (which it can in DragonFly).
2238          * Otherwise we'd have to implement a multi-pass or flag the lock
2239          * failures and retry.
2240          *
2241          * The reclamation code interlocks with the sync list's token
2242          * (by removing the vnode from the scan list) before unlocking
2243          * the inode, giving us time to ref the inode.
2244          */
2245         /*flags = VMSC_GETVP;*/
2246         flags = 0;
2247         if (waitfor & MNT_LAZY)
2248                 flags |= VMSC_ONEPASS;
2249
2250         /*
2251          * Preflush the vnodes using a normal transaction before interlocking
2252          * with a flush transaction.  We do this to try to run as much of
2253          * the compression as possible outside the flush transaction.
2254          *
2255          * For efficiency do an async pass before making sure with a
2256          * synchronous pass on all related buffer cache buffers.
2257          */
2258         hammer2_trans_init(pmp, 0);
2259         info.error = 0;
2260         info.waitfor = MNT_NOWAIT;
2261         vsyncscan(mp, flags | VMSC_NOWAIT, hammer2_sync_scan2, &info);
2262         info.waitfor = MNT_WAIT;
2263         vsyncscan(mp, flags, hammer2_sync_scan2, &info);
2264         hammer2_trans_done(pmp);
2265
2266         /*
2267          * Start our flush transaction.  This does not return until all
2268          * concurrent transactions have completed and will prevent any
2269          * new transactions from running concurrently, except for the
2270          * buffer cache transactions.
2271          *
2272          * NOTE!  It is still possible for the paging code to push pages
2273          *        out via a UIO_NOCOPY hammer2_vop_write() during the main
2274          *        flush.
2275          */
2276         hammer2_trans_init(pmp, HAMMER2_TRANS_ISFLUSH);
2277         hammer2_inode_run_sideq(pmp);
2278
2279         info.error = 0;
2280         info.waitfor = MNT_NOWAIT;
2281         vsyncscan(mp, flags | VMSC_NOWAIT, hammer2_sync_scan2, &info);
2282         info.waitfor = MNT_WAIT;
2283         vsyncscan(mp, flags, hammer2_sync_scan2, &info);
2284         hammer2_bioq_sync(pmp);
2285
2286         /*
2287          * Use the XOP interface to concurrently flush all nodes to
2288          * synchronize the PFSROOT subtopology to the media.  A standard
2289          * end-of-scan ENOENT error indicates cluster sufficiency.
2290          *
2291          * Note that this flush will not be visible on crash recovery until
2292          * we flush the super-root topology in the next loop.
2293          *
2294          * XXX For now wait for all flushes to complete.
2295          */
2296         if (iroot) {
2297                 xop = hammer2_xop_alloc(iroot, HAMMER2_XOP_MODIFYING);
2298                 hammer2_xop_start(&xop->head, hammer2_inode_xop_flush);
2299                 error = hammer2_xop_collect(&xop->head,
2300                                             HAMMER2_XOP_COLLECT_WAITALL);
2301                 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP);
2302                 if (error == ENOENT)
2303                         error = 0;
2304         } else {
2305                 error = 0;
2306         }
2307         hammer2_trans_done(pmp);
2308
2309         return (error);
2310 }
2311
2312 /*
2313  * Sync passes.
2314  *
2315  * Note that we ignore the tranasction mtid we got above.  Instead,
2316  * each vfsync below will ultimately get its own via TRANS_BUFCACHE
2317  * transactions.
2318  */
2319 static int
2320 hammer2_sync_scan2(struct mount *mp, struct vnode *vp, void *data)
2321 {
2322         struct hammer2_sync_info *info = data;
2323         hammer2_inode_t *ip;
2324         int error;
2325
2326         /*
2327          * Degenerate cases.  Note that ip == NULL typically means the
2328          * syncer vnode itself and we don't want to vclrisdirty() in that
2329          * situation.
2330          */
2331         ip = VTOI(vp);
2332         if (ip == NULL) {
2333                 return(0);
2334         }
2335         if (vp->v_type == VNON || vp->v_type == VBAD) {
2336                 vclrisdirty(vp);
2337                 return(0);
2338         }
2339
2340         /*
2341          * VOP_FSYNC will start a new transaction so replicate some code
2342          * here to do it inline (see hammer2_vop_fsync()).
2343          *
2344          * WARNING: The vfsync interacts with the buffer cache and might
2345          *          block, we can't hold the inode lock at that time.
2346          *          However, we MUST ref ip before blocking to ensure that
2347          *          it isn't ripped out from under us (since we do not
2348          *          hold a lock on the vnode).
2349          */
2350         hammer2_inode_ref(ip);
2351         if ((ip->flags & HAMMER2_INODE_MODIFIED) ||
2352             !RB_EMPTY(&vp->v_rbdirty_tree)) {
2353                 vfsync(vp, info->waitfor, 1, NULL, NULL);
2354                 if (ip->flags & (HAMMER2_INODE_RESIZED |
2355                                  HAMMER2_INODE_MODIFIED)) {
2356                         hammer2_inode_lock(ip, 0);
2357                         if (ip->flags & (HAMMER2_INODE_RESIZED |
2358                                          HAMMER2_INODE_MODIFIED)) {
2359                                 hammer2_inode_chain_sync(ip);
2360                         }
2361                         hammer2_inode_unlock(ip);
2362                 }
2363         }
2364         if ((ip->flags & HAMMER2_INODE_MODIFIED) == 0 &&
2365             RB_EMPTY(&vp->v_rbdirty_tree)) {
2366                 vclrisdirty(vp);
2367         }
2368
2369         hammer2_inode_drop(ip);
2370 #if 1
2371         error = 0;
2372         if (error)
2373                 info->error = error;
2374 #endif
2375         return(0);
2376 }
2377
2378 static
2379 int
2380 hammer2_vfs_vptofh(struct vnode *vp, struct fid *fhp)
2381 {
2382         hammer2_inode_t *ip;
2383
2384         KKASSERT(MAXFIDSZ >= 16);
2385         ip = VTOI(vp);
2386         fhp->fid_len = offsetof(struct fid, fid_data[16]);
2387         fhp->fid_ext = 0;
2388         ((hammer2_tid_t *)fhp->fid_data)[0] = ip->meta.inum;
2389         ((hammer2_tid_t *)fhp->fid_data)[1] = 0;
2390
2391         return 0;
2392 }
2393
2394 static
2395 int
2396 hammer2_vfs_fhtovp(struct mount *mp, struct vnode *rootvp,
2397                struct fid *fhp, struct vnode **vpp)
2398 {
2399         hammer2_pfs_t *pmp;
2400         hammer2_tid_t inum;
2401         int error;
2402
2403         pmp = MPTOPMP(mp);
2404         inum = ((hammer2_tid_t *)fhp->fid_data)[0] & HAMMER2_DIRHASH_USERMSK;
2405         if (vpp) {
2406                 if (inum == 1)
2407                         error = hammer2_vfs_root(mp, vpp);
2408                 else
2409                         error = hammer2_vfs_vget(mp, NULL, inum, vpp);
2410         } else {
2411                 error = 0;
2412         }
2413         if (error)
2414                 kprintf("fhtovp: %016jx -> %p, %d\n", inum, *vpp, error);
2415         return error;
2416 }
2417
2418 static
2419 int
2420 hammer2_vfs_checkexp(struct mount *mp, struct sockaddr *nam,
2421                  int *exflagsp, struct ucred **credanonp)
2422 {
2423         hammer2_pfs_t *pmp;
2424         struct netcred *np;
2425         int error;
2426
2427         pmp = MPTOPMP(mp);
2428         np = vfs_export_lookup(mp, &pmp->export, nam);
2429         if (np) {
2430                 *exflagsp = np->netc_exflags;
2431                 *credanonp = &np->netc_anon;
2432                 error = 0;
2433         } else {
2434                 error = EACCES;
2435         }
2436         return error;
2437 }
2438
2439 /*
2440  * Support code for hammer2_vfs_mount().  Read, verify, and install the volume
2441  * header into the HMP
2442  *
2443  * XXX read four volhdrs and use the one with the highest TID whos CRC
2444  *     matches.
2445  *
2446  * XXX check iCRCs.
2447  *
2448  * XXX For filesystems w/ less than 4 volhdrs, make sure to not write to
2449  *     nonexistant locations.
2450  *
2451  * XXX Record selected volhdr and ring updates to each of 4 volhdrs
2452  */
2453 static
2454 int
2455 hammer2_install_volume_header(hammer2_dev_t *hmp)
2456 {
2457         hammer2_volume_data_t *vd;
2458         struct buf *bp;
2459         hammer2_crc32_t crc0, crc, bcrc0, bcrc;
2460         int error_reported;
2461         int error;
2462         int valid;
2463         int i;
2464
2465         error_reported = 0;
2466         error = 0;
2467         valid = 0;
2468         bp = NULL;
2469
2470         /*
2471          * There are up to 4 copies of the volume header (syncs iterate
2472          * between them so there is no single master).  We don't trust the
2473          * volu_size field so we don't know precisely how large the filesystem
2474          * is, so depend on the OS to return an error if we go beyond the
2475          * block device's EOF.
2476          */
2477         for (i = 0; i < HAMMER2_NUM_VOLHDRS; i++) {
2478                 error = bread(hmp->devvp, i * HAMMER2_ZONE_BYTES64,
2479                               HAMMER2_VOLUME_BYTES, &bp);
2480                 if (error) {
2481                         brelse(bp);
2482                         bp = NULL;
2483                         continue;
2484                 }
2485
2486                 vd = (struct hammer2_volume_data *) bp->b_data;
2487                 if ((vd->magic != HAMMER2_VOLUME_ID_HBO) &&
2488                     (vd->magic != HAMMER2_VOLUME_ID_ABO)) {
2489                         brelse(bp);
2490                         bp = NULL;
2491                         continue;
2492                 }
2493
2494                 if (vd->magic == HAMMER2_VOLUME_ID_ABO) {
2495                         /* XXX: Reversed-endianness filesystem */
2496                         kprintf("hammer2: reverse-endian filesystem detected");
2497                         brelse(bp);
2498                         bp = NULL;
2499                         continue;
2500                 }
2501
2502                 crc = vd->icrc_sects[HAMMER2_VOL_ICRC_SECT0];
2503                 crc0 = hammer2_icrc32(bp->b_data + HAMMER2_VOLUME_ICRC0_OFF,
2504                                       HAMMER2_VOLUME_ICRC0_SIZE);
2505                 bcrc = vd->icrc_sects[HAMMER2_VOL_ICRC_SECT1];
2506                 bcrc0 = hammer2_icrc32(bp->b_data + HAMMER2_VOLUME_ICRC1_OFF,
2507                                        HAMMER2_VOLUME_ICRC1_SIZE);
2508                 if ((crc0 != crc) || (bcrc0 != bcrc)) {
2509                         kprintf("hammer2 volume header crc "
2510                                 "mismatch copy #%d %08x/%08x\n",
2511                                 i, crc0, crc);
2512                         error_reported = 1;
2513                         brelse(bp);
2514                         bp = NULL;
2515                         continue;
2516                 }
2517                 if (valid == 0 || hmp->voldata.mirror_tid < vd->mirror_tid) {
2518                         valid = 1;
2519                         hmp->voldata = *vd;
2520                         hmp->volhdrno = i;
2521                 }
2522                 brelse(bp);
2523                 bp = NULL;
2524         }
2525         if (valid) {
2526                 hmp->volsync = hmp->voldata;
2527                 error = 0;
2528                 if (error_reported || bootverbose || 1) { /* 1/DEBUG */
2529                         kprintf("hammer2: using volume header #%d\n",
2530                                 hmp->volhdrno);
2531                 }
2532         } else {
2533                 error = EINVAL;
2534                 kprintf("hammer2: no valid volume headers found!\n");
2535         }
2536         return (error);
2537 }
2538
2539 /*
2540  * This handles hysteresis on regular file flushes.  Because the BIOs are
2541  * routed to a thread it is possible for an excessive number to build up
2542  * and cause long front-end stalls long before the runningbuffspace limit
2543  * is hit, so we implement hammer2_flush_pipe to control the
2544  * hysteresis.
2545  *
2546  * This is a particular problem when compression is used.
2547  */
2548 void
2549 hammer2_lwinprog_ref(hammer2_pfs_t *pmp)
2550 {
2551         atomic_add_int(&pmp->count_lwinprog, 1);
2552 }
2553
2554 void
2555 hammer2_lwinprog_drop(hammer2_pfs_t *pmp)
2556 {
2557         int lwinprog;
2558
2559         lwinprog = atomic_fetchadd_int(&pmp->count_lwinprog, -1);
2560         if ((lwinprog & HAMMER2_LWINPROG_WAITING) &&
2561             (lwinprog & HAMMER2_LWINPROG_MASK) <= hammer2_flush_pipe * 2 / 3) {
2562                 atomic_clear_int(&pmp->count_lwinprog,
2563                                  HAMMER2_LWINPROG_WAITING);
2564                 wakeup(&pmp->count_lwinprog);
2565         }
2566         if ((lwinprog & HAMMER2_LWINPROG_WAITING0) &&
2567             (lwinprog & HAMMER2_LWINPROG_MASK) <= 0) {
2568                 atomic_clear_int(&pmp->count_lwinprog,
2569                                  HAMMER2_LWINPROG_WAITING0);
2570                 wakeup(&pmp->count_lwinprog);
2571         }
2572 }
2573
2574 void
2575 hammer2_lwinprog_wait(hammer2_pfs_t *pmp, int flush_pipe)
2576 {
2577         int lwinprog;
2578         int lwflag = (flush_pipe) ? HAMMER2_LWINPROG_WAITING :
2579                                     HAMMER2_LWINPROG_WAITING0;
2580
2581         for (;;) {
2582                 lwinprog = pmp->count_lwinprog;
2583                 cpu_ccfence();
2584                 if ((lwinprog & HAMMER2_LWINPROG_MASK) <= flush_pipe)
2585                         break;
2586                 tsleep_interlock(&pmp->count_lwinprog, 0);
2587                 atomic_set_int(&pmp->count_lwinprog, lwflag);
2588                 lwinprog = pmp->count_lwinprog;
2589                 if ((lwinprog & HAMMER2_LWINPROG_MASK) <= flush_pipe)
2590                         break;
2591                 tsleep(&pmp->count_lwinprog, PINTERLOCKED, "h2wpipe", hz);
2592         }
2593 }
2594
2595 /*
2596  * Manage excessive memory resource use for chain and related
2597  * structures.
2598  */
2599 void
2600 hammer2_pfs_memory_wait(hammer2_pfs_t *pmp)
2601 {
2602         uint32_t waiting;
2603         uint32_t count;
2604         uint32_t limit;
2605 #if 0
2606         static int zzticks;
2607 #endif
2608
2609         /*
2610          * Atomic check condition and wait.  Also do an early speedup of
2611          * the syncer to try to avoid hitting the wait.
2612          */
2613         for (;;) {
2614                 waiting = pmp->inmem_dirty_chains;
2615                 cpu_ccfence();
2616                 count = waiting & HAMMER2_DIRTYCHAIN_MASK;
2617
2618                 limit = pmp->mp->mnt_nvnodelistsize / 10;
2619                 if (limit < hammer2_limit_dirty_chains)
2620                         limit = hammer2_limit_dirty_chains;
2621                 if (limit < 1000)
2622                         limit = 1000;
2623
2624 #if 0
2625                 if ((int)(ticks - zzticks) > hz) {
2626                         zzticks = ticks;
2627                         kprintf("count %ld %ld\n", count, limit);
2628                 }
2629 #endif
2630
2631                 /*
2632                  * Block if there are too many dirty chains present, wait
2633                  * for the flush to clean some out.
2634                  */
2635                 if (count > limit) {
2636                         tsleep_interlock(&pmp->inmem_dirty_chains, 0);
2637                         if (atomic_cmpset_int(&pmp->inmem_dirty_chains,
2638                                                waiting,
2639                                        waiting | HAMMER2_DIRTYCHAIN_WAITING)) {
2640                                 speedup_syncer(pmp->mp);
2641                                 tsleep(&pmp->inmem_dirty_chains, PINTERLOCKED,
2642                                        "chnmem", hz);
2643                         }
2644                         continue;       /* loop on success or fail */
2645                 }
2646
2647                 /*
2648                  * Try to start an early flush before we are forced to block.
2649                  */
2650                 if (count > limit * 7 / 10)
2651                         speedup_syncer(pmp->mp);
2652                 break;
2653         }
2654 }
2655
2656 void
2657 hammer2_pfs_memory_inc(hammer2_pfs_t *pmp)
2658 {
2659         if (pmp) {
2660                 atomic_add_int(&pmp->inmem_dirty_chains, 1);
2661         }
2662 }
2663
2664 void
2665 hammer2_pfs_memory_wakeup(hammer2_pfs_t *pmp)
2666 {
2667         uint32_t waiting;
2668
2669         if (pmp == NULL)
2670                 return;
2671
2672         for (;;) {
2673                 waiting = pmp->inmem_dirty_chains;
2674                 cpu_ccfence();
2675                 if (atomic_cmpset_int(&pmp->inmem_dirty_chains,
2676                                        waiting,
2677                                        (waiting - 1) &
2678                                         ~HAMMER2_DIRTYCHAIN_WAITING)) {
2679                         break;
2680                 }
2681         }
2682
2683         if (waiting & HAMMER2_DIRTYCHAIN_WAITING)
2684                 wakeup(&pmp->inmem_dirty_chains);
2685 }
2686
2687 /*
2688  * Debugging
2689  */
2690 void
2691 hammer2_dump_chain(hammer2_chain_t *chain, int tab, int *countp, char pfx)
2692 {
2693         hammer2_chain_t *scan;
2694         hammer2_chain_t *parent;
2695
2696         --*countp;
2697         if (*countp == 0) {
2698                 kprintf("%*.*s...\n", tab, tab, "");
2699                 return;
2700         }
2701         if (*countp < 0)
2702                 return;
2703         kprintf("%*.*s%c-chain %p.%d %016jx/%d mir=%016jx\n",
2704                 tab, tab, "", pfx,
2705                 chain, chain->bref.type,
2706                 chain->bref.key, chain->bref.keybits,
2707                 chain->bref.mirror_tid);
2708
2709         kprintf("%*.*s      [%08x] (%s) refs=%d",
2710                 tab, tab, "",
2711                 chain->flags,
2712                 ((chain->bref.type == HAMMER2_BREF_TYPE_INODE &&
2713                 chain->data) ?  (char *)chain->data->ipdata.filename : "?"),
2714                 chain->refs);
2715
2716         parent = chain->parent;
2717         if (parent)
2718                 kprintf("\n%*.*s      p=%p [pflags %08x prefs %d",
2719                         tab, tab, "",
2720                         parent, parent->flags, parent->refs);
2721         if (RB_EMPTY(&chain->core.rbtree)) {
2722                 kprintf("\n");
2723         } else {
2724                 kprintf(" {\n");
2725                 RB_FOREACH(scan, hammer2_chain_tree, &chain->core.rbtree)
2726                         hammer2_dump_chain(scan, tab + 4, countp, 'a');
2727                 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE && chain->data)
2728                         kprintf("%*.*s}(%s)\n", tab, tab, "",
2729                                 chain->data->ipdata.filename);
2730                 else
2731                         kprintf("%*.*s}\n", tab, tab, "");
2732         }
2733 }