xref: /dflybsd-src/sys/vfs/hammer2/hammer2_vfsops.c (revision 5f39c7e70ca0960d1868c75a449064df712dbb10)
1 /*
2  * Copyright (c) 2011-2014 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 
62 #include "hammer2.h"
63 #include "hammer2_lz4.h"
64 
65 #include "zlib/hammer2_zlib.h"
66 
67 #define REPORT_REFS_ERRORS 1	/* XXX remove me */
68 
69 MALLOC_DEFINE(M_OBJCACHE, "objcache", "Object Cache");
70 
71 struct hammer2_sync_info {
72 	hammer2_trans_t trans;
73 	int error;
74 	int waitfor;
75 };
76 
77 TAILQ_HEAD(hammer2_mntlist, hammer2_mount);
78 TAILQ_HEAD(hammer2_pfslist, hammer2_pfsmount);
79 static struct hammer2_mntlist hammer2_mntlist;
80 static struct hammer2_pfslist hammer2_pfslist;
81 static struct lock hammer2_mntlk;
82 
83 int hammer2_debug;
84 int hammer2_cluster_enable = 1;
85 int hammer2_hardlink_enable = 1;
86 int hammer2_flush_pipe = 100;
87 int hammer2_synchronous_flush = 1;
88 int hammer2_dio_count;
89 long hammer2_limit_dirty_chains;
90 long hammer2_iod_file_read;
91 long hammer2_iod_meta_read;
92 long hammer2_iod_indr_read;
93 long hammer2_iod_fmap_read;
94 long hammer2_iod_volu_read;
95 long hammer2_iod_file_write;
96 long hammer2_iod_meta_write;
97 long hammer2_iod_indr_write;
98 long hammer2_iod_fmap_write;
99 long hammer2_iod_volu_write;
100 long hammer2_ioa_file_read;
101 long hammer2_ioa_meta_read;
102 long hammer2_ioa_indr_read;
103 long hammer2_ioa_fmap_read;
104 long hammer2_ioa_volu_read;
105 long hammer2_ioa_fmap_write;
106 long hammer2_ioa_file_write;
107 long hammer2_ioa_meta_write;
108 long hammer2_ioa_indr_write;
109 long hammer2_ioa_volu_write;
110 
111 MALLOC_DECLARE(C_BUFFER);
112 MALLOC_DEFINE(C_BUFFER, "compbuffer", "Buffer used for compression.");
113 
114 MALLOC_DECLARE(D_BUFFER);
115 MALLOC_DEFINE(D_BUFFER, "decompbuffer", "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_enable, CTLFLAG_RW,
122 	   &hammer2_cluster_enable, 0, "");
123 SYSCTL_INT(_vfs_hammer2, OID_AUTO, hardlink_enable, CTLFLAG_RW,
124 	   &hammer2_hardlink_enable, 0, "");
125 SYSCTL_INT(_vfs_hammer2, OID_AUTO, flush_pipe, CTLFLAG_RW,
126 	   &hammer2_flush_pipe, 0, "");
127 SYSCTL_INT(_vfs_hammer2, OID_AUTO, synchronous_flush, CTLFLAG_RW,
128 	   &hammer2_synchronous_flush, 0, "");
129 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, limit_dirty_chains, CTLFLAG_RW,
130 	   &hammer2_limit_dirty_chains, 0, "");
131 SYSCTL_INT(_vfs_hammer2, OID_AUTO, dio_count, CTLFLAG_RD,
132 	   &hammer2_dio_count, 0, "");
133 
134 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_read, CTLFLAG_RW,
135 	   &hammer2_iod_file_read, 0, "");
136 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_meta_read, CTLFLAG_RW,
137 	   &hammer2_iod_meta_read, 0, "");
138 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_indr_read, CTLFLAG_RW,
139 	   &hammer2_iod_indr_read, 0, "");
140 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_fmap_read, CTLFLAG_RW,
141 	   &hammer2_iod_fmap_read, 0, "");
142 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_volu_read, CTLFLAG_RW,
143 	   &hammer2_iod_volu_read, 0, "");
144 
145 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_file_write, CTLFLAG_RW,
146 	   &hammer2_iod_file_write, 0, "");
147 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_meta_write, CTLFLAG_RW,
148 	   &hammer2_iod_meta_write, 0, "");
149 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_indr_write, CTLFLAG_RW,
150 	   &hammer2_iod_indr_write, 0, "");
151 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_fmap_write, CTLFLAG_RW,
152 	   &hammer2_iod_fmap_write, 0, "");
153 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, iod_volu_write, CTLFLAG_RW,
154 	   &hammer2_iod_volu_write, 0, "");
155 
156 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, ioa_file_read, CTLFLAG_RW,
157 	   &hammer2_ioa_file_read, 0, "");
158 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, ioa_meta_read, CTLFLAG_RW,
159 	   &hammer2_ioa_meta_read, 0, "");
160 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, ioa_indr_read, CTLFLAG_RW,
161 	   &hammer2_ioa_indr_read, 0, "");
162 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, ioa_fmap_read, CTLFLAG_RW,
163 	   &hammer2_ioa_fmap_read, 0, "");
164 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, ioa_volu_read, CTLFLAG_RW,
165 	   &hammer2_ioa_volu_read, 0, "");
166 
167 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, ioa_file_write, CTLFLAG_RW,
168 	   &hammer2_ioa_file_write, 0, "");
169 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, ioa_meta_write, CTLFLAG_RW,
170 	   &hammer2_ioa_meta_write, 0, "");
171 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, ioa_indr_write, CTLFLAG_RW,
172 	   &hammer2_ioa_indr_write, 0, "");
173 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, ioa_fmap_write, CTLFLAG_RW,
174 	   &hammer2_ioa_fmap_write, 0, "");
175 SYSCTL_LONG(_vfs_hammer2, OID_AUTO, ioa_volu_write, CTLFLAG_RW,
176 	   &hammer2_ioa_volu_write, 0, "");
177 
178 static int hammer2_vfs_init(struct vfsconf *conf);
179 static int hammer2_vfs_uninit(struct vfsconf *vfsp);
180 static int hammer2_vfs_mount(struct mount *mp, char *path, caddr_t data,
181 				struct ucred *cred);
182 static int hammer2_remount(hammer2_mount_t *, struct mount *, char *,
183 				struct vnode *, struct ucred *);
184 static int hammer2_recovery(hammer2_mount_t *hmp);
185 static int hammer2_vfs_unmount(struct mount *mp, int mntflags);
186 static int hammer2_vfs_root(struct mount *mp, struct vnode **vpp);
187 static int hammer2_vfs_statfs(struct mount *mp, struct statfs *sbp,
188 				struct ucred *cred);
189 static int hammer2_vfs_statvfs(struct mount *mp, struct statvfs *sbp,
190 				struct ucred *cred);
191 static int hammer2_vfs_vget(struct mount *mp, struct vnode *dvp,
192 				ino_t ino, struct vnode **vpp);
193 static int hammer2_vfs_fhtovp(struct mount *mp, struct vnode *rootvp,
194 				struct fid *fhp, struct vnode **vpp);
195 static int hammer2_vfs_vptofh(struct vnode *vp, struct fid *fhp);
196 static int hammer2_vfs_checkexp(struct mount *mp, struct sockaddr *nam,
197 				int *exflagsp, struct ucred **credanonp);
198 
199 static int hammer2_install_volume_header(hammer2_mount_t *hmp);
200 static int hammer2_sync_scan2(struct mount *mp, struct vnode *vp, void *data);
201 
202 static void hammer2_write_thread(void *arg);
203 
204 static void hammer2_vfs_unmount_hmp1(struct mount *mp, hammer2_mount_t *hmp);
205 static void hammer2_vfs_unmount_hmp2(struct mount *mp, hammer2_mount_t *hmp);
206 
207 /*
208  * Functions for compression in threads,
209  * from hammer2_vnops.c
210  */
211 static void hammer2_write_file_core(struct buf *bp, hammer2_trans_t *trans,
212 				hammer2_inode_t *ip,
213 				hammer2_inode_data_t *ipdata,
214 				hammer2_cluster_t *cparent,
215 				hammer2_key_t lbase, int ioflag, int pblksize,
216 				int *errorp);
217 static void hammer2_compress_and_write(struct buf *bp, hammer2_trans_t *trans,
218 				hammer2_inode_t *ip,
219 				const hammer2_inode_data_t *ipdata,
220 				hammer2_cluster_t *cparent,
221 				hammer2_key_t lbase, int ioflag,
222 				int pblksize, int *errorp, int comp_algo);
223 static void hammer2_zero_check_and_write(struct buf *bp,
224 				hammer2_trans_t *trans, hammer2_inode_t *ip,
225 				const hammer2_inode_data_t *ipdata,
226 				hammer2_cluster_t *cparent,
227 				hammer2_key_t lbase,
228 				int ioflag, int pblksize, int *errorp);
229 static int test_block_zeros(const char *buf, size_t bytes);
230 static void zero_write(struct buf *bp, hammer2_trans_t *trans,
231 				hammer2_inode_t *ip,
232 				const hammer2_inode_data_t *ipdata,
233 				hammer2_cluster_t *cparent,
234 				hammer2_key_t lbase,
235 				int *errorp);
236 static void hammer2_write_bp(hammer2_cluster_t *cluster, struct buf *bp,
237 				int ioflag, int pblksize, int *errorp);
238 
239 static int hammer2_rcvdmsg(kdmsg_msg_t *msg);
240 static void hammer2_autodmsg(kdmsg_msg_t *msg);
241 static int hammer2_lnk_span_reply(kdmsg_state_t *state, kdmsg_msg_t *msg);
242 
243 
244 /*
245  * HAMMER2 vfs operations.
246  */
247 static struct vfsops hammer2_vfsops = {
248 	.vfs_init	= hammer2_vfs_init,
249 	.vfs_uninit	= hammer2_vfs_uninit,
250 	.vfs_sync	= hammer2_vfs_sync,
251 	.vfs_mount	= hammer2_vfs_mount,
252 	.vfs_unmount	= hammer2_vfs_unmount,
253 	.vfs_root 	= hammer2_vfs_root,
254 	.vfs_statfs	= hammer2_vfs_statfs,
255 	.vfs_statvfs	= hammer2_vfs_statvfs,
256 	.vfs_vget	= hammer2_vfs_vget,
257 	.vfs_vptofh	= hammer2_vfs_vptofh,
258 	.vfs_fhtovp	= hammer2_vfs_fhtovp,
259 	.vfs_checkexp	= hammer2_vfs_checkexp
260 };
261 
262 MALLOC_DEFINE(M_HAMMER2, "HAMMER2-mount", "");
263 
264 VFS_SET(hammer2_vfsops, hammer2, 0);
265 MODULE_VERSION(hammer2, 1);
266 
267 static
268 int
269 hammer2_vfs_init(struct vfsconf *conf)
270 {
271 	static struct objcache_malloc_args margs_read;
272 	static struct objcache_malloc_args margs_write;
273 
274 	int error;
275 
276 	error = 0;
277 
278 	if (HAMMER2_BLOCKREF_BYTES != sizeof(struct hammer2_blockref))
279 		error = EINVAL;
280 	if (HAMMER2_INODE_BYTES != sizeof(struct hammer2_inode_data))
281 		error = EINVAL;
282 	if (HAMMER2_VOLUME_BYTES != sizeof(struct hammer2_volume_data))
283 		error = EINVAL;
284 
285 	if (error)
286 		kprintf("HAMMER2 structure size mismatch; cannot continue.\n");
287 
288 	margs_read.objsize = 65536;
289 	margs_read.mtype = D_BUFFER;
290 
291 	margs_write.objsize = 32768;
292 	margs_write.mtype = C_BUFFER;
293 
294 	cache_buffer_read = objcache_create(margs_read.mtype->ks_shortdesc,
295 				0, 1, NULL, NULL, NULL, objcache_malloc_alloc,
296 				objcache_malloc_free, &margs_read);
297 	cache_buffer_write = objcache_create(margs_write.mtype->ks_shortdesc,
298 				0, 1, NULL, NULL, NULL, objcache_malloc_alloc,
299 				objcache_malloc_free, &margs_write);
300 
301 	lockinit(&hammer2_mntlk, "mntlk", 0, 0);
302 	TAILQ_INIT(&hammer2_mntlist);
303 	TAILQ_INIT(&hammer2_pfslist);
304 
305 	hammer2_limit_dirty_chains = desiredvnodes / 10;
306 
307 	hammer2_trans_manage_init();
308 
309 	return (error);
310 }
311 
312 static
313 int
314 hammer2_vfs_uninit(struct vfsconf *vfsp __unused)
315 {
316 	objcache_destroy(cache_buffer_read);
317 	objcache_destroy(cache_buffer_write);
318 	return 0;
319 }
320 
321 /*
322  * Core PFS allocator.  Used to allocate the pmp structure for PFS cluster
323  * mounts and the spmp structure for media (hmp) structures.
324  */
325 static hammer2_pfsmount_t *
326 hammer2_pfsalloc(const hammer2_inode_data_t *ipdata, hammer2_tid_t alloc_tid)
327 {
328 	hammer2_pfsmount_t *pmp;
329 
330 	pmp = kmalloc(sizeof(*pmp), M_HAMMER2, M_WAITOK | M_ZERO);
331 	kmalloc_create(&pmp->minode, "HAMMER2-inodes");
332 	kmalloc_create(&pmp->mmsg, "HAMMER2-pfsmsg");
333 	lockinit(&pmp->lock, "pfslk", 0, 0);
334 	spin_init(&pmp->inum_spin);
335 	RB_INIT(&pmp->inum_tree);
336 	TAILQ_INIT(&pmp->unlinkq);
337 	spin_init(&pmp->unlinkq_spin);
338 
339 	pmp->alloc_tid = alloc_tid + 1;	  /* our first media transaction id */
340 	pmp->flush_tid = pmp->alloc_tid;
341 	if (ipdata) {
342 		pmp->inode_tid = ipdata->pfs_inum + 1;
343 		pmp->pfs_clid = ipdata->pfs_clid;
344 	}
345 	mtx_init(&pmp->wthread_mtx);
346 	bioq_init(&pmp->wthread_bioq);
347 
348 	return pmp;
349 }
350 
351 /*
352  * Mount or remount HAMMER2 fileystem from physical media
353  *
354  *	mountroot
355  *		mp		mount point structure
356  *		path		NULL
357  *		data		<unused>
358  *		cred		<unused>
359  *
360  *	mount
361  *		mp		mount point structure
362  *		path		path to mount point
363  *		data		pointer to argument structure in user space
364  *			volume	volume path (device@LABEL form)
365  *			hflags	user mount flags
366  *		cred		user credentials
367  *
368  * RETURNS:	0	Success
369  *		!0	error number
370  */
371 static
372 int
373 hammer2_vfs_mount(struct mount *mp, char *path, caddr_t data,
374 		  struct ucred *cred)
375 {
376 	struct hammer2_mount_info info;
377 	hammer2_pfsmount_t *pmp;
378 	hammer2_pfsmount_t *spmp;
379 	hammer2_mount_t *hmp;
380 	hammer2_key_t key_next;
381 	hammer2_key_t key_dummy;
382 	hammer2_key_t lhc;
383 	struct vnode *devvp;
384 	struct nlookupdata nd;
385 	hammer2_chain_t *parent;
386 	hammer2_chain_t *rchain;
387 	hammer2_cluster_t *cluster;
388 	hammer2_cluster_t *cparent;
389 	const hammer2_inode_data_t *ipdata;
390 	hammer2_blockref_t bref;
391 	struct file *fp;
392 	char devstr[MNAMELEN];
393 	size_t size;
394 	size_t done;
395 	char *dev;
396 	char *label;
397 	int ronly = 1;
398 	int error;
399 	int cache_index;
400 	int ddflag;
401 	int i;
402 
403 	hmp = NULL;
404 	pmp = NULL;
405 	dev = NULL;
406 	label = NULL;
407 	devvp = NULL;
408 	cache_index = -1;
409 
410 	kprintf("hammer2_mount\n");
411 
412 	if (path == NULL) {
413 		/*
414 		 * Root mount
415 		 */
416 		bzero(&info, sizeof(info));
417 		info.cluster_fd = -1;
418 		return (EOPNOTSUPP);
419 	} else {
420 		/*
421 		 * Non-root mount or updating a mount
422 		 */
423 		error = copyin(data, &info, sizeof(info));
424 		if (error)
425 			return (error);
426 
427 		error = copyinstr(info.volume, devstr, MNAMELEN - 1, &done);
428 		if (error)
429 			return (error);
430 
431 		/* Extract device and label */
432 		dev = devstr;
433 		label = strchr(devstr, '@');
434 		if (label == NULL ||
435 		    ((label + 1) - dev) > done) {
436 			return (EINVAL);
437 		}
438 		*label = '\0';
439 		label++;
440 		if (*label == '\0')
441 			return (EINVAL);
442 
443 		if (mp->mnt_flag & MNT_UPDATE) {
444 			/* Update mount */
445 			/* HAMMER2 implements NFS export via mountctl */
446 			pmp = MPTOPMP(mp);
447 			for (i = 0; i < pmp->iroot->cluster.nchains; ++i) {
448 				hmp = pmp->iroot->cluster.array[i]->hmp;
449 				devvp = hmp->devvp;
450 				error = hammer2_remount(hmp, mp, path,
451 							devvp, cred);
452 				if (error)
453 					break;
454 			}
455 			/*hammer2_inode_install_hidden(pmp);*/
456 
457 			return error;
458 		}
459 	}
460 
461 	/*
462 	 * HMP device mount
463 	 *
464 	 * Lookup name and verify it refers to a block device.
465 	 */
466 	error = nlookup_init(&nd, dev, UIO_SYSSPACE, NLC_FOLLOW);
467 	if (error == 0)
468 		error = nlookup(&nd);
469 	if (error == 0)
470 		error = cache_vref(&nd.nl_nch, nd.nl_cred, &devvp);
471 	nlookup_done(&nd);
472 
473 	if (error == 0) {
474 		if (vn_isdisk(devvp, &error))
475 			error = vfs_mountedon(devvp);
476 	}
477 
478 	/*
479 	 * Determine if the device has already been mounted.  After this
480 	 * check hmp will be non-NULL if we are doing the second or more
481 	 * hammer2 mounts from the same device.
482 	 */
483 	lockmgr(&hammer2_mntlk, LK_EXCLUSIVE);
484 	TAILQ_FOREACH(hmp, &hammer2_mntlist, mntentry) {
485 		if (hmp->devvp == devvp)
486 			break;
487 	}
488 
489 	/*
490 	 * Open the device if this isn't a secondary mount and construct
491 	 * the H2 device mount (hmp).
492 	 */
493 	if (hmp == NULL) {
494 		hammer2_chain_t *schain;
495 		hammer2_xid_t xid;
496 
497 		if (error == 0 && vcount(devvp) > 0)
498 			error = EBUSY;
499 
500 		/*
501 		 * Now open the device
502 		 */
503 		if (error == 0) {
504 			ronly = ((mp->mnt_flag & MNT_RDONLY) != 0);
505 			vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
506 			error = vinvalbuf(devvp, V_SAVE, 0, 0);
507 			if (error == 0) {
508 				error = VOP_OPEN(devvp,
509 						 ronly ? FREAD : FREAD | FWRITE,
510 						 FSCRED, NULL);
511 			}
512 			vn_unlock(devvp);
513 		}
514 		if (error && devvp) {
515 			vrele(devvp);
516 			devvp = NULL;
517 		}
518 		if (error) {
519 			lockmgr(&hammer2_mntlk, LK_RELEASE);
520 			return error;
521 		}
522 		hmp = kmalloc(sizeof(*hmp), M_HAMMER2, M_WAITOK | M_ZERO);
523 		hmp->ronly = ronly;
524 		hmp->devvp = devvp;
525 		kmalloc_create(&hmp->mchain, "HAMMER2-chains");
526 		TAILQ_INSERT_TAIL(&hammer2_mntlist, hmp, mntentry);
527 		RB_INIT(&hmp->iotree);
528 
529 		lockinit(&hmp->vollk, "h2vol", 0, 0);
530 
531 		/*
532 		 * vchain setup. vchain.data is embedded.
533 		 * vchain.refs is initialized and will never drop to 0.
534 		 *
535 		 * NOTE! voldata is not yet loaded.
536 		 */
537 		hmp->vchain.hmp = hmp;
538 		hmp->vchain.refs = 1;
539 		hmp->vchain.data = (void *)&hmp->voldata;
540 		hmp->vchain.bref.type = HAMMER2_BREF_TYPE_VOLUME;
541 		hmp->vchain.bref.data_off = 0 | HAMMER2_PBUFRADIX;
542 		hmp->vchain.bref.mirror_tid = hmp->voldata.mirror_tid;
543 		hmp->vchain.delete_xid = HAMMER2_XID_MAX;
544 
545 		hammer2_chain_core_alloc(NULL, &hmp->vchain, NULL);
546 		/* hmp->vchain.u.xxx is left NULL */
547 
548 		/*
549 		 * fchain setup.  fchain.data is embedded.
550 		 * fchain.refs is initialized and will never drop to 0.
551 		 *
552 		 * The data is not used but needs to be initialized to
553 		 * pass assertion muster.  We use this chain primarily
554 		 * as a placeholder for the freemap's top-level RBTREE
555 		 * so it does not interfere with the volume's topology
556 		 * RBTREE.
557 		 */
558 		hmp->fchain.hmp = hmp;
559 		hmp->fchain.refs = 1;
560 		hmp->fchain.data = (void *)&hmp->voldata.freemap_blockset;
561 		hmp->fchain.bref.type = HAMMER2_BREF_TYPE_FREEMAP;
562 		hmp->fchain.bref.data_off = 0 | HAMMER2_PBUFRADIX;
563 		hmp->fchain.bref.mirror_tid = hmp->voldata.freemap_tid;
564 		hmp->fchain.bref.methods =
565 			HAMMER2_ENC_CHECK(HAMMER2_CHECK_FREEMAP) |
566 			HAMMER2_ENC_COMP(HAMMER2_COMP_NONE);
567 		hmp->fchain.delete_xid = HAMMER2_XID_MAX;
568 
569 		hammer2_chain_core_alloc(NULL, &hmp->fchain, NULL);
570 		/* hmp->fchain.u.xxx is left NULL */
571 
572 		/*
573 		 * Install the volume header and initialize fields from
574 		 * voldata.
575 		 */
576 		error = hammer2_install_volume_header(hmp);
577 		if (error) {
578 			++hmp->pmp_count;
579 			hammer2_vfs_unmount_hmp1(mp, hmp);
580 			hammer2_vfs_unmount_hmp2(mp, hmp);
581 			lockmgr(&hammer2_mntlk, LK_RELEASE);
582 			hammer2_vfs_unmount(mp, MNT_FORCE);
583 			return error;
584 		}
585 
586 		/*
587 		 * Really important to get these right or flush will get
588 		 * confused.
589 		 */
590 		hmp->spmp = hammer2_pfsalloc(NULL, hmp->voldata.mirror_tid);
591 		kprintf("alloc spmp %p tid %016jx\n",
592 			hmp->spmp, hmp->voldata.mirror_tid);
593 		spmp = hmp->spmp;
594 		spmp->inode_tid = 1;
595 
596 		xid = 0;
597 		hmp->vchain.bref.mirror_tid = hmp->voldata.mirror_tid;
598 		hmp->vchain.bref.modify_tid = hmp->vchain.bref.mirror_tid;
599 		hmp->vchain.modify_xid = xid;
600 		hmp->vchain.update_xlo = xid;
601 		hmp->vchain.update_xhi = xid;
602 		hmp->vchain.pmp = spmp;
603 		hmp->fchain.bref.mirror_tid = hmp->voldata.freemap_tid;
604 		hmp->fchain.bref.modify_tid = hmp->fchain.bref.mirror_tid;
605 		hmp->fchain.modify_xid = xid;
606 		hmp->fchain.update_xlo = xid;
607 		hmp->fchain.update_xhi = xid;
608 		hmp->fchain.pmp = spmp;
609 
610 		/*
611 		 * First locate the super-root inode, which is key 0
612 		 * relative to the volume header's blockset.
613 		 *
614 		 * Then locate the root inode by scanning the directory keyspace
615 		 * represented by the label.
616 		 */
617 		parent = hammer2_chain_lookup_init(&hmp->vchain, 0);
618 		schain = hammer2_chain_lookup(&parent, &key_dummy,
619 				      HAMMER2_SROOT_KEY, HAMMER2_SROOT_KEY,
620 				      &cache_index, 0, &ddflag);
621 		hammer2_chain_lookup_done(parent);
622 		if (schain == NULL) {
623 			kprintf("hammer2_mount: invalid super-root\n");
624 			++hmp->pmp_count;
625 			hammer2_vfs_unmount_hmp1(mp, hmp);
626 			hammer2_vfs_unmount_hmp2(mp, hmp);
627 			lockmgr(&hammer2_mntlk, LK_RELEASE);
628 			hammer2_vfs_unmount(mp, MNT_FORCE);
629 			return EINVAL;
630 		}
631 
632 		/*
633 		 * Sanity-check schain's pmp, finish initializing spmp.
634 		 */
635 		KKASSERT(schain->pmp == spmp);
636 		spmp->pfs_clid = schain->data->ipdata.pfs_clid;
637 
638 		/*
639 		 * NOTE: The CHAIN_PFSROOT is not set on the super-root inode.
640 		 * NOTE: inode_get sucks up schain's lock.
641 		 */
642 		cluster = hammer2_cluster_from_chain(schain);
643 		spmp->iroot = hammer2_inode_get(spmp, NULL, cluster);
644 		spmp->spmp_hmp = hmp;
645 		hammer2_inode_ref(spmp->iroot);
646 		hammer2_inode_unlock_ex(spmp->iroot, cluster);
647 		schain = NULL;
648 		/* leave spmp->iroot with one ref */
649 
650 		if ((mp->mnt_flag & MNT_RDONLY) == 0) {
651 			error = hammer2_recovery(hmp);
652 			/* XXX do something with error */
653 		}
654 		++hmp->pmp_count;
655 
656 		/*
657 		 * XXX RDONLY stuff is totally broken FIXME XXX
658 		 *
659 		 * Automatic LNK_CONN
660 		 * Automatic handling of received LNK_SPAN
661 		 * Automatic handling of received LNK_CIRC
662 		 * No automatic LNK_SPAN generation - we do this ourselves
663 		 * No automatic LNK_CIRC generation - we do this ourselves
664 		 */
665 		kdmsg_iocom_init(&hmp->iocom, hmp,
666 				 KDMSG_IOCOMF_AUTOCONN |
667 				 KDMSG_IOCOMF_AUTORXSPAN |
668 				 KDMSG_IOCOMF_AUTORXCIRC,
669 				 hmp->mchain, hammer2_rcvdmsg);
670 
671 		/*
672 		 * Ref the cluster management messaging descriptor.  The mount
673 		 * program deals with the other end of the communications pipe.
674 		 */
675 		fp = holdfp(curproc->p_fd, info.cluster_fd, -1);
676 		if (fp) {
677 			hammer2_cluster_reconnect(hmp, fp);
678 		} else {
679 			kprintf("hammer2_mount: bad cluster_fd!\n");
680 		}
681 	} else {
682 		spmp = hmp->spmp;
683 		++hmp->pmp_count;
684 	}
685 
686 	/*
687 	 * Lookup mount point under the media-localized super-root.
688 	 *
689 	 * cluster->pmp will incorrectly point to spmp and must be fixed
690 	 * up later on.
691 	 */
692 	cparent = hammer2_inode_lock_ex(spmp->iroot);
693 	lhc = hammer2_dirhash(label, strlen(label));
694 	cluster = hammer2_cluster_lookup(cparent, &key_next,
695 				      lhc, lhc + HAMMER2_DIRHASH_LOMASK,
696 				      0, &ddflag);
697 	while (cluster) {
698 		if (hammer2_cluster_type(cluster) == HAMMER2_BREF_TYPE_INODE &&
699 		    strcmp(label,
700 		       hammer2_cluster_data(cluster)->ipdata.filename) == 0) {
701 			break;
702 		}
703 		cluster = hammer2_cluster_next(cparent, cluster, &key_next,
704 					    key_next,
705 					    lhc + HAMMER2_DIRHASH_LOMASK, 0);
706 	}
707 	hammer2_inode_unlock_ex(spmp->iroot, cparent);
708 
709 	if (cluster == NULL) {
710 		kprintf("hammer2_mount: PFS label not found\n");
711 		hammer2_vfs_unmount_hmp1(mp, hmp);
712 		hammer2_vfs_unmount_hmp2(mp, hmp);
713 		lockmgr(&hammer2_mntlk, LK_RELEASE);
714 		hammer2_vfs_unmount(mp, MNT_FORCE);
715 		return EINVAL;
716 	}
717 
718 	for (i = 0; i < cluster->nchains; ++i) {
719 		rchain = cluster->array[i];
720 		KKASSERT(rchain->pmp == NULL);
721 		if (rchain->flags & HAMMER2_CHAIN_MOUNTED) {
722 			kprintf("hammer2_mount: PFS label already mounted!\n");
723 			hammer2_cluster_unlock(cluster);
724 			hammer2_vfs_unmount_hmp1(mp, hmp);
725 			hammer2_vfs_unmount_hmp2(mp, hmp);
726 			lockmgr(&hammer2_mntlk, LK_RELEASE);
727 			hammer2_vfs_unmount(mp, MNT_FORCE);
728 			return EBUSY;
729 		}
730 #if 0
731 		if (rchain->flags & HAMMER2_CHAIN_RECYCLE) {
732 			kprintf("hammer2_mount: PFS label is recycling\n");
733 			hammer2_cluster_unlock(cluster);
734 			hammer2_vfs_unmount_hmp1(mp, hmp);
735 			hammer2_vfs_unmount_hmp2(mp, hmp);
736 			lockmgr(&hammer2_mntlk, LK_RELEASE);
737 			hammer2_vfs_unmount(mp, MNT_FORCE);
738 			return EBUSY;
739 		}
740 #endif
741 	}
742 
743 	/*
744 	 * Check to see if the cluster id is already mounted at the mount
745 	 * point.  If it is, add us to the cluster.
746 	 */
747 	ipdata = &hammer2_cluster_data(cluster)->ipdata;
748 	hammer2_cluster_bref(cluster, &bref);
749 	TAILQ_FOREACH(pmp, &hammer2_pfslist, mntentry) {
750 		if (pmp->spmp_hmp == NULL &&
751 		    bcmp(&pmp->pfs_clid, &ipdata->pfs_clid,
752 			 sizeof(pmp->pfs_clid)) == 0) {
753 			break;
754 		}
755 	}
756 
757 	if (pmp) {
758 		int i;
759 		int j;
760 
761 		hammer2_inode_ref(pmp->iroot);
762 		ccms_thread_lock(&pmp->iroot->topo_cst, CCMS_STATE_EXCLUSIVE);
763 
764 		if (pmp->iroot->cluster.nchains + cluster->nchains >
765 		    HAMMER2_MAXCLUSTER) {
766 			kprintf("hammer2_mount: cluster full!\n");
767 
768 			ccms_thread_unlock(&pmp->iroot->topo_cst);
769 			hammer2_inode_drop(pmp->iroot);
770 
771 			hammer2_cluster_unlock(cluster);
772 			hammer2_vfs_unmount_hmp1(mp, hmp);
773 			hammer2_vfs_unmount_hmp2(mp, hmp);
774 			lockmgr(&hammer2_mntlk, LK_RELEASE);
775 			hammer2_vfs_unmount(mp, MNT_FORCE);
776 			return EBUSY;
777 		}
778 		kprintf("hammer2_vfs_mount: Adding pfs to existing cluster\n");
779 		j = pmp->iroot->cluster.nchains;
780 		for (i = 0; i < cluster->nchains; ++i) {
781 			rchain = cluster->array[i];
782 			KKASSERT(rchain->pmp == NULL);
783 			rchain->pmp = pmp;
784 			hammer2_chain_ref(cluster->array[i]);
785 			pmp->iroot->cluster.array[j] = cluster->array[i];
786 			++j;
787 		}
788 		pmp->iroot->cluster.nchains = j;
789 		ccms_thread_unlock(&pmp->iroot->topo_cst);
790 		hammer2_inode_drop(pmp->iroot);
791 		hammer2_cluster_unlock(cluster);
792 		lockmgr(&hammer2_mntlk, LK_RELEASE);
793 
794 		kprintf("ok\n");
795 		hammer2_inode_install_hidden(pmp);
796 
797 		return ERANGE;
798 	}
799 
800 	/*
801 	 * Block device opened successfully, finish initializing the
802 	 * mount structure.
803 	 *
804 	 * From this point on we have to call hammer2_unmount() on failure.
805 	 */
806 	pmp = hammer2_pfsalloc(ipdata, bref.mirror_tid);
807 	kprintf("PMP mirror_tid is %016jx\n", bref.mirror_tid);
808 	for (i = 0; i < cluster->nchains; ++i) {
809 		rchain = cluster->array[i];
810 		KKASSERT(rchain->pmp == NULL);
811 		rchain->pmp = pmp;
812 		atomic_set_int(&rchain->flags, HAMMER2_CHAIN_MOUNTED);
813 	}
814 	cluster->pmp = pmp;
815 
816 	ccms_domain_init(&pmp->ccms_dom);
817 	TAILQ_INSERT_TAIL(&hammer2_pfslist, pmp, mntentry);
818 	lockmgr(&hammer2_mntlk, LK_RELEASE);
819 
820 	kprintf("hammer2_mount hmp=%p pmp=%p pmpcnt=%d\n",
821 		hmp, pmp, hmp->pmp_count);
822 
823 	mp->mnt_flag = MNT_LOCAL;
824 	mp->mnt_kern_flag |= MNTK_ALL_MPSAFE;	/* all entry pts are SMP */
825 	mp->mnt_kern_flag |= MNTK_THR_SYNC;	/* new vsyncscan semantics */
826 
827 	/*
828 	 * required mount structure initializations
829 	 */
830 	mp->mnt_stat.f_iosize = HAMMER2_PBUFSIZE;
831 	mp->mnt_stat.f_bsize = HAMMER2_PBUFSIZE;
832 
833 	mp->mnt_vstat.f_frsize = HAMMER2_PBUFSIZE;
834 	mp->mnt_vstat.f_bsize = HAMMER2_PBUFSIZE;
835 
836 	/*
837 	 * Optional fields
838 	 */
839 	mp->mnt_iosize_max = MAXPHYS;
840 	mp->mnt_data = (qaddr_t)pmp;
841 	pmp->mp = mp;
842 
843 	/*
844 	 * After this point hammer2_vfs_unmount() has visibility on hmp
845 	 * and manual hmp1/hmp2 calls are not needed on fatal errors.
846 	 */
847 	pmp->iroot = hammer2_inode_get(pmp, NULL, cluster);
848 	hammer2_inode_ref(pmp->iroot);		/* ref for pmp->iroot */
849 	hammer2_inode_unlock_ex(pmp->iroot, cluster);
850 
851 	/*
852 	 * The logical file buffer bio write thread handles things
853 	 * like physical block assignment and compression.
854 	 *
855 	 * (only applicable to pfs mounts, not applicable to spmp)
856 	 */
857 	pmp->wthread_destroy = 0;
858 	lwkt_create(hammer2_write_thread, pmp,
859 		    &pmp->wthread_td, NULL, 0, -1, "hwrite-%s", label);
860 
861 	/*
862 	 * With the cluster operational install ihidden.
863 	 * (only applicable to pfs mounts, not applicable to spmp)
864 	 */
865 	hammer2_inode_install_hidden(pmp);
866 
867 	/*
868 	 * Finish setup
869 	 */
870 	vfs_getnewfsid(mp);
871 	vfs_add_vnodeops(mp, &hammer2_vnode_vops, &mp->mnt_vn_norm_ops);
872 	vfs_add_vnodeops(mp, &hammer2_spec_vops, &mp->mnt_vn_spec_ops);
873 	vfs_add_vnodeops(mp, &hammer2_fifo_vops, &mp->mnt_vn_fifo_ops);
874 
875 	copyinstr(info.volume, mp->mnt_stat.f_mntfromname, MNAMELEN - 1, &size);
876 	bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
877 	bzero(mp->mnt_stat.f_mntonname, sizeof(mp->mnt_stat.f_mntonname));
878 	copyinstr(path, mp->mnt_stat.f_mntonname,
879 		  sizeof(mp->mnt_stat.f_mntonname) - 1,
880 		  &size);
881 
882 	/*
883 	 * Initial statfs to prime mnt_stat.
884 	 */
885 	hammer2_vfs_statfs(mp, &mp->mnt_stat, cred);
886 
887 	return 0;
888 }
889 
890 /*
891  * Handle bioq for strategy write
892  */
893 static
894 void
895 hammer2_write_thread(void *arg)
896 {
897 	hammer2_pfsmount_t *pmp;
898 	struct bio *bio;
899 	struct buf *bp;
900 	hammer2_trans_t trans;
901 	struct vnode *vp;
902 	hammer2_inode_t *ip;
903 	hammer2_cluster_t *cparent;
904 	hammer2_inode_data_t *wipdata;
905 	hammer2_key_t lbase;
906 	int lblksize;
907 	int pblksize;
908 	int error;
909 
910 	pmp = arg;
911 
912 	mtx_lock(&pmp->wthread_mtx);
913 	while (pmp->wthread_destroy == 0) {
914 		if (bioq_first(&pmp->wthread_bioq) == NULL) {
915 			mtxsleep(&pmp->wthread_bioq, &pmp->wthread_mtx,
916 				 0, "h2bioqw", 0);
917 		}
918 		cparent = NULL;
919 
920 		hammer2_trans_init(&trans, pmp, HAMMER2_TRANS_BUFCACHE);
921 
922 		while ((bio = bioq_takefirst(&pmp->wthread_bioq)) != NULL) {
923 			/*
924 			 * dummy bio for synchronization.  The transaction
925 			 * must be reinitialized.
926 			 */
927 			if (bio->bio_buf == NULL) {
928 				bio->bio_flags |= BIO_DONE;
929 				wakeup(bio);
930 				hammer2_trans_done(&trans);
931 				hammer2_trans_init(&trans, pmp,
932 						   HAMMER2_TRANS_BUFCACHE);
933 				continue;
934 			}
935 
936 			/*
937 			 * else normal bio processing
938 			 */
939 			mtx_unlock(&pmp->wthread_mtx);
940 
941 			hammer2_lwinprog_drop(pmp);
942 
943 			error = 0;
944 			bp = bio->bio_buf;
945 			vp = bp->b_vp;
946 			ip = VTOI(vp);
947 
948 			/*
949 			 * Inode is modified, flush size and mtime changes
950 			 * to ensure that the file size remains consistent
951 			 * with the buffers being flushed.
952 			 *
953 			 * NOTE: The inode_fsync() call only flushes the
954 			 *	 inode's meta-data state, it doesn't try
955 			 *	 to flush underlying buffers or chains.
956 			 */
957 			cparent = hammer2_inode_lock_ex(ip);
958 			if (ip->flags & (HAMMER2_INODE_RESIZED |
959 					 HAMMER2_INODE_MTIME)) {
960 				hammer2_inode_fsync(&trans, ip, cparent);
961 			}
962 			wipdata = hammer2_cluster_modify_ip(&trans, ip,
963 							 cparent, 0);
964 			lblksize = hammer2_calc_logical(ip, bio->bio_offset,
965 							&lbase, NULL);
966 			pblksize = hammer2_calc_physical(ip, wipdata, lbase);
967 			hammer2_write_file_core(bp, &trans, ip, wipdata,
968 						cparent,
969 						lbase, IO_ASYNC,
970 						pblksize, &error);
971 			hammer2_cluster_modsync(cparent);
972 			hammer2_inode_unlock_ex(ip, cparent);
973 			if (error) {
974 				kprintf("hammer2: error in buffer write\n");
975 				bp->b_flags |= B_ERROR;
976 				bp->b_error = EIO;
977 			}
978 			biodone(bio);
979 			mtx_lock(&pmp->wthread_mtx);
980 		}
981 		hammer2_trans_done(&trans);
982 	}
983 	pmp->wthread_destroy = -1;
984 	wakeup(&pmp->wthread_destroy);
985 
986 	mtx_unlock(&pmp->wthread_mtx);
987 }
988 
989 void
990 hammer2_bioq_sync(hammer2_pfsmount_t *pmp)
991 {
992 	struct bio sync_bio;
993 
994 	bzero(&sync_bio, sizeof(sync_bio));	/* dummy with no bio_buf */
995 	mtx_lock(&pmp->wthread_mtx);
996 	if (pmp->wthread_destroy == 0 &&
997 	    TAILQ_FIRST(&pmp->wthread_bioq.queue)) {
998 		bioq_insert_tail(&pmp->wthread_bioq, &sync_bio);
999 		while ((sync_bio.bio_flags & BIO_DONE) == 0)
1000 			mtxsleep(&sync_bio, &pmp->wthread_mtx, 0, "h2bioq", 0);
1001 	}
1002 	mtx_unlock(&pmp->wthread_mtx);
1003 }
1004 
1005 /*
1006  * Return a chain suitable for I/O, creating the chain if necessary
1007  * and assigning its physical block.
1008  */
1009 static
1010 hammer2_cluster_t *
1011 hammer2_assign_physical(hammer2_trans_t *trans,
1012 			hammer2_inode_t *ip, hammer2_cluster_t *cparent,
1013 			hammer2_key_t lbase, int pblksize, int *errorp)
1014 {
1015 	hammer2_cluster_t *cluster;
1016 	hammer2_cluster_t *dparent;
1017 	hammer2_key_t key_dummy;
1018 	int pradix = hammer2_getradix(pblksize);
1019 	int ddflag;
1020 
1021 	/*
1022 	 * Locate the chain associated with lbase, return a locked chain.
1023 	 * However, do not instantiate any data reference (which utilizes a
1024 	 * device buffer) because we will be using direct IO via the
1025 	 * logical buffer cache buffer.
1026 	 */
1027 	*errorp = 0;
1028 	KKASSERT(pblksize >= HAMMER2_ALLOC_MIN);
1029 retry:
1030 	dparent = hammer2_cluster_lookup_init(cparent, 0);
1031 	cluster = hammer2_cluster_lookup(dparent, &key_dummy,
1032 				     lbase, lbase,
1033 				     HAMMER2_LOOKUP_NODATA, &ddflag);
1034 
1035 	if (cluster == NULL) {
1036 		/*
1037 		 * We found a hole, create a new chain entry.
1038 		 *
1039 		 * NOTE: DATA chains are created without device backing
1040 		 *	 store (nor do we want any).
1041 		 */
1042 		*errorp = hammer2_cluster_create(trans, dparent, &cluster,
1043 					       lbase, HAMMER2_PBUFRADIX,
1044 					       HAMMER2_BREF_TYPE_DATA,
1045 					       pblksize);
1046 		if (cluster == NULL) {
1047 			hammer2_cluster_lookup_done(dparent);
1048 			panic("hammer2_cluster_create: par=%p error=%d\n",
1049 				dparent->focus, *errorp);
1050 			goto retry;
1051 		}
1052 		/*ip->delta_dcount += pblksize;*/
1053 	} else {
1054 		switch (hammer2_cluster_type(cluster)) {
1055 		case HAMMER2_BREF_TYPE_INODE:
1056 			/*
1057 			 * The data is embedded in the inode.  The
1058 			 * caller is responsible for marking the inode
1059 			 * modified and copying the data to the embedded
1060 			 * area.
1061 			 */
1062 			break;
1063 		case HAMMER2_BREF_TYPE_DATA:
1064 			if (hammer2_cluster_bytes(cluster) != pblksize) {
1065 				hammer2_cluster_resize(trans, ip,
1066 						     dparent, cluster,
1067 						     pradix,
1068 						     HAMMER2_MODIFY_OPTDATA);
1069 			}
1070 			hammer2_cluster_modify(trans, cluster,
1071 					     HAMMER2_MODIFY_OPTDATA);
1072 			break;
1073 		default:
1074 			panic("hammer2_assign_physical: bad type");
1075 			/* NOT REACHED */
1076 			break;
1077 		}
1078 	}
1079 
1080 	/*
1081 	 * Cleanup.  If cluster wound up being the inode itself, i.e.
1082 	 * the DIRECTDATA case for offset 0, then we need to update cparent.
1083 	 * The caller expects cparent to not become stale.
1084 	 */
1085 	hammer2_cluster_lookup_done(dparent);
1086 	/* dparent = NULL; safety */
1087 	if (cluster && ddflag)
1088 		hammer2_cluster_replace_locked(cparent, cluster);
1089 	return (cluster);
1090 }
1091 
1092 /*
1093  * From hammer2_vnops.c.
1094  * The core write function which determines which path to take
1095  * depending on compression settings.
1096  */
1097 static
1098 void
1099 hammer2_write_file_core(struct buf *bp, hammer2_trans_t *trans,
1100 			hammer2_inode_t *ip, hammer2_inode_data_t *ipdata,
1101 			hammer2_cluster_t *cparent,
1102 			hammer2_key_t lbase, int ioflag, int pblksize,
1103 			int *errorp)
1104 {
1105 	hammer2_cluster_t *cluster;
1106 
1107 	switch(HAMMER2_DEC_COMP(ipdata->comp_algo)) {
1108 	case HAMMER2_COMP_NONE:
1109 		/*
1110 		 * We have to assign physical storage to the buffer
1111 		 * we intend to dirty or write now to avoid deadlocks
1112 		 * in the strategy code later.
1113 		 *
1114 		 * This can return NOOFFSET for inode-embedded data.
1115 		 * The strategy code will take care of it in that case.
1116 		 */
1117 		cluster = hammer2_assign_physical(trans, ip, cparent,
1118 						lbase, pblksize,
1119 						errorp);
1120 		hammer2_write_bp(cluster, bp, ioflag, pblksize, errorp);
1121 		if (cluster)
1122 			hammer2_cluster_unlock(cluster);
1123 		break;
1124 	case HAMMER2_COMP_AUTOZERO:
1125 		/*
1126 		 * Check for zero-fill only
1127 		 */
1128 		hammer2_zero_check_and_write(bp, trans, ip,
1129 				    ipdata, cparent, lbase,
1130 				    ioflag, pblksize, errorp);
1131 		break;
1132 	case HAMMER2_COMP_LZ4:
1133 	case HAMMER2_COMP_ZLIB:
1134 	default:
1135 		/*
1136 		 * Check for zero-fill and attempt compression.
1137 		 */
1138 		hammer2_compress_and_write(bp, trans, ip,
1139 					   ipdata, cparent,
1140 					   lbase, ioflag,
1141 					   pblksize, errorp,
1142 					   ipdata->comp_algo);
1143 		break;
1144 	}
1145 }
1146 
1147 /*
1148  * Generic function that will perform the compression in compression
1149  * write path. The compression algorithm is determined by the settings
1150  * obtained from inode.
1151  */
1152 static
1153 void
1154 hammer2_compress_and_write(struct buf *bp, hammer2_trans_t *trans,
1155 	hammer2_inode_t *ip, const hammer2_inode_data_t *ipdata,
1156 	hammer2_cluster_t *cparent,
1157 	hammer2_key_t lbase, int ioflag, int pblksize,
1158 	int *errorp, int comp_algo)
1159 {
1160 	hammer2_cluster_t *cluster;
1161 	hammer2_chain_t *chain;
1162 	int comp_size;
1163 	int comp_block_size;
1164 	int i;
1165 	char *comp_buffer;
1166 
1167 	if (test_block_zeros(bp->b_data, pblksize)) {
1168 		zero_write(bp, trans, ip, ipdata, cparent, lbase, errorp);
1169 		return;
1170 	}
1171 
1172 	comp_size = 0;
1173 	comp_buffer = NULL;
1174 
1175 	KKASSERT(pblksize / 2 <= 32768);
1176 
1177 	if (ip->comp_heuristic < 8 || (ip->comp_heuristic & 7) == 0) {
1178 		z_stream strm_compress;
1179 		int comp_level;
1180 		int ret;
1181 
1182 		switch(HAMMER2_DEC_COMP(comp_algo)) {
1183 		case HAMMER2_COMP_LZ4:
1184 			comp_buffer = objcache_get(cache_buffer_write,
1185 						   M_INTWAIT);
1186 			comp_size = LZ4_compress_limitedOutput(
1187 					bp->b_data,
1188 					&comp_buffer[sizeof(int)],
1189 					pblksize,
1190 					pblksize / 2 - sizeof(int));
1191 			/*
1192 			 * We need to prefix with the size, LZ4
1193 			 * doesn't do it for us.  Add the related
1194 			 * overhead.
1195 			 */
1196 			*(int *)comp_buffer = comp_size;
1197 			if (comp_size)
1198 				comp_size += sizeof(int);
1199 			break;
1200 		case HAMMER2_COMP_ZLIB:
1201 			comp_level = HAMMER2_DEC_LEVEL(comp_algo);
1202 			if (comp_level == 0)
1203 				comp_level = 6;	/* default zlib compression */
1204 			else if (comp_level < 6)
1205 				comp_level = 6;
1206 			else if (comp_level > 9)
1207 				comp_level = 9;
1208 			ret = deflateInit(&strm_compress, comp_level);
1209 			if (ret != Z_OK) {
1210 				kprintf("HAMMER2 ZLIB: fatal error "
1211 					"on deflateInit.\n");
1212 			}
1213 
1214 			comp_buffer = objcache_get(cache_buffer_write,
1215 						   M_INTWAIT);
1216 			strm_compress.next_in = bp->b_data;
1217 			strm_compress.avail_in = pblksize;
1218 			strm_compress.next_out = comp_buffer;
1219 			strm_compress.avail_out = pblksize / 2;
1220 			ret = deflate(&strm_compress, Z_FINISH);
1221 			if (ret == Z_STREAM_END) {
1222 				comp_size = pblksize / 2 -
1223 					    strm_compress.avail_out;
1224 			} else {
1225 				comp_size = 0;
1226 			}
1227 			ret = deflateEnd(&strm_compress);
1228 			break;
1229 		default:
1230 			kprintf("Error: Unknown compression method.\n");
1231 			kprintf("Comp_method = %d.\n", comp_algo);
1232 			break;
1233 		}
1234 	}
1235 
1236 	if (comp_size == 0) {
1237 		/*
1238 		 * compression failed or turned off
1239 		 */
1240 		comp_block_size = pblksize;	/* safety */
1241 		if (++ip->comp_heuristic > 128)
1242 			ip->comp_heuristic = 8;
1243 	} else {
1244 		/*
1245 		 * compression succeeded
1246 		 */
1247 		ip->comp_heuristic = 0;
1248 		if (comp_size <= 1024) {
1249 			comp_block_size = 1024;
1250 		} else if (comp_size <= 2048) {
1251 			comp_block_size = 2048;
1252 		} else if (comp_size <= 4096) {
1253 			comp_block_size = 4096;
1254 		} else if (comp_size <= 8192) {
1255 			comp_block_size = 8192;
1256 		} else if (comp_size <= 16384) {
1257 			comp_block_size = 16384;
1258 		} else if (comp_size <= 32768) {
1259 			comp_block_size = 32768;
1260 		} else {
1261 			panic("hammer2: WRITE PATH: "
1262 			      "Weird comp_size value.");
1263 			/* NOT REACHED */
1264 			comp_block_size = pblksize;
1265 		}
1266 	}
1267 
1268 	cluster = hammer2_assign_physical(trans, ip, cparent,
1269 					  lbase, comp_block_size,
1270 					  errorp);
1271 	ipdata = &hammer2_cluster_data(cparent)->ipdata;
1272 
1273 	if (*errorp) {
1274 		kprintf("WRITE PATH: An error occurred while "
1275 			"assigning physical space.\n");
1276 		KKASSERT(cluster == NULL);
1277 		goto done;
1278 	}
1279 
1280 	for (i = 0; i < cluster->nchains; ++i) {
1281 		hammer2_io_t *dio;
1282 		char *bdata;
1283 		int temp_check;
1284 
1285 		chain = cluster->array[i];
1286 		KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED);
1287 
1288 		switch(chain->bref.type) {
1289 		case HAMMER2_BREF_TYPE_INODE:
1290 			KKASSERT(chain->data->ipdata.op_flags &
1291 				 HAMMER2_OPFLAG_DIRECTDATA);
1292 			KKASSERT(bp->b_loffset == 0);
1293 			bcopy(bp->b_data, chain->data->ipdata.u.data,
1294 			      HAMMER2_EMBEDDED_BYTES);
1295 			break;
1296 		case HAMMER2_BREF_TYPE_DATA:
1297 			temp_check = HAMMER2_DEC_CHECK(chain->bref.methods);
1298 
1299 			/*
1300 			 * Optimize out the read-before-write
1301 			 * if possible.
1302 			 */
1303 			*errorp = hammer2_io_newnz(chain->hmp,
1304 						   chain->bref.data_off,
1305 						   chain->bytes,
1306 						   &dio);
1307 			if (*errorp) {
1308 				hammer2_io_brelse(&dio);
1309 				kprintf("hammer2: WRITE PATH: "
1310 					"dbp bread error\n");
1311 				break;
1312 			}
1313 			bdata = hammer2_io_data(dio, chain->bref.data_off);
1314 
1315 			/*
1316 			 * When loading the block make sure we don't
1317 			 * leave garbage after the compressed data.
1318 			 */
1319 			if (comp_size) {
1320 				chain->bref.methods =
1321 					HAMMER2_ENC_COMP(comp_algo) +
1322 					HAMMER2_ENC_CHECK(temp_check);
1323 				bcopy(comp_buffer, bdata, comp_size);
1324 				if (comp_size != comp_block_size) {
1325 					bzero(bdata + comp_size,
1326 					      comp_block_size - comp_size);
1327 				}
1328 			} else {
1329 				chain->bref.methods =
1330 					HAMMER2_ENC_COMP(
1331 						HAMMER2_COMP_NONE) +
1332 					HAMMER2_ENC_CHECK(temp_check);
1333 				bcopy(bp->b_data, bdata, pblksize);
1334 			}
1335 
1336 			/*
1337 			 * Device buffer is now valid, chain is no
1338 			 * longer in the initial state.
1339 			 */
1340 			atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
1341 
1342 			/* Now write the related bdp. */
1343 			if (ioflag & IO_SYNC) {
1344 				/*
1345 				 * Synchronous I/O requested.
1346 				 */
1347 				hammer2_io_bwrite(&dio);
1348 			/*
1349 			} else if ((ioflag & IO_DIRECT) &&
1350 				   loff + n == pblksize) {
1351 				hammer2_io_bdwrite(&dio);
1352 			*/
1353 			} else if (ioflag & IO_ASYNC) {
1354 				hammer2_io_bawrite(&dio);
1355 			} else {
1356 				hammer2_io_bdwrite(&dio);
1357 			}
1358 			break;
1359 		default:
1360 			panic("hammer2_write_bp: bad chain type %d\n",
1361 				chain->bref.type);
1362 			/* NOT REACHED */
1363 			break;
1364 		}
1365 	}
1366 done:
1367 	if (cluster)
1368 		hammer2_cluster_unlock(cluster);
1369 	if (comp_buffer)
1370 		objcache_put(cache_buffer_write, comp_buffer);
1371 }
1372 
1373 /*
1374  * Function that performs zero-checking and writing without compression,
1375  * it corresponds to default zero-checking path.
1376  */
1377 static
1378 void
1379 hammer2_zero_check_and_write(struct buf *bp, hammer2_trans_t *trans,
1380 	hammer2_inode_t *ip, const hammer2_inode_data_t *ipdata,
1381 	hammer2_cluster_t *cparent,
1382 	hammer2_key_t lbase, int ioflag, int pblksize, int *errorp)
1383 {
1384 	hammer2_cluster_t *cluster;
1385 
1386 	if (test_block_zeros(bp->b_data, pblksize)) {
1387 		zero_write(bp, trans, ip, ipdata, cparent, lbase, errorp);
1388 	} else {
1389 		cluster = hammer2_assign_physical(trans, ip, cparent,
1390 						  lbase, pblksize, errorp);
1391 		hammer2_write_bp(cluster, bp, ioflag, pblksize, errorp);
1392 		if (cluster)
1393 			hammer2_cluster_unlock(cluster);
1394 	}
1395 }
1396 
1397 /*
1398  * A function to test whether a block of data contains only zeros,
1399  * returns TRUE (non-zero) if the block is all zeros.
1400  */
1401 static
1402 int
1403 test_block_zeros(const char *buf, size_t bytes)
1404 {
1405 	size_t i;
1406 
1407 	for (i = 0; i < bytes; i += sizeof(long)) {
1408 		if (*(const long *)(buf + i) != 0)
1409 			return (0);
1410 	}
1411 	return (1);
1412 }
1413 
1414 /*
1415  * Function to "write" a block that contains only zeros.
1416  */
1417 static
1418 void
1419 zero_write(struct buf *bp, hammer2_trans_t *trans,
1420 	hammer2_inode_t *ip, const hammer2_inode_data_t *ipdata,
1421 	hammer2_cluster_t *cparent,
1422 	hammer2_key_t lbase, int *errorp __unused)
1423 {
1424 	hammer2_cluster_t *cluster;
1425 	hammer2_media_data_t *data;
1426 	hammer2_key_t key_dummy;
1427 	int ddflag;
1428 
1429 	cparent = hammer2_cluster_lookup_init(cparent, 0);
1430 	cluster = hammer2_cluster_lookup(cparent, &key_dummy, lbase, lbase,
1431 				     HAMMER2_LOOKUP_NODATA, &ddflag);
1432 	if (cluster) {
1433 		data = hammer2_cluster_wdata(cluster);
1434 
1435 		if (ddflag) {
1436 			KKASSERT(cluster->focus->flags &
1437 				 HAMMER2_CHAIN_MODIFIED);
1438 			bzero(data->ipdata.u.data, HAMMER2_EMBEDDED_BYTES);
1439 			hammer2_cluster_modsync(cluster);
1440 		} else {
1441 			hammer2_cluster_delete(trans, cluster, 0);
1442 		}
1443 		hammer2_cluster_unlock(cluster);
1444 	}
1445 	hammer2_cluster_lookup_done(cparent);
1446 }
1447 
1448 /*
1449  * Function to write the data as it is, without performing any sort of
1450  * compression. This function is used in path without compression and
1451  * default zero-checking path.
1452  */
1453 static
1454 void
1455 hammer2_write_bp(hammer2_cluster_t *cluster, struct buf *bp, int ioflag,
1456 				int pblksize, int *errorp)
1457 {
1458 	hammer2_chain_t *chain;
1459 	hammer2_io_t *dio;
1460 	char *bdata;
1461 	int error;
1462 	int i;
1463 	int temp_check;
1464 
1465 	error = 0;	/* XXX TODO below */
1466 
1467 	for (i = 0; i < cluster->nchains; ++i) {
1468 		chain = cluster->array[i];
1469 
1470 		temp_check = HAMMER2_DEC_CHECK(chain->bref.methods);
1471 
1472 		KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED);
1473 
1474 		switch(chain->bref.type) {
1475 		case HAMMER2_BREF_TYPE_INODE:
1476 			KKASSERT(chain->data->ipdata.op_flags &
1477 				 HAMMER2_OPFLAG_DIRECTDATA);
1478 			KKASSERT(bp->b_loffset == 0);
1479 			bcopy(bp->b_data, chain->data->ipdata.u.data,
1480 			      HAMMER2_EMBEDDED_BYTES);
1481 			error = 0;
1482 			break;
1483 		case HAMMER2_BREF_TYPE_DATA:
1484 			error = hammer2_io_newnz(chain->hmp,
1485 						 chain->bref.data_off,
1486 						 chain->bytes, &dio);
1487 			if (error) {
1488 				hammer2_io_bqrelse(&dio);
1489 				kprintf("hammer2: WRITE PATH: "
1490 					"dbp bread error\n");
1491 				break;
1492 			}
1493 			bdata = hammer2_io_data(dio, chain->bref.data_off);
1494 
1495 			chain->bref.methods = HAMMER2_ENC_COMP(
1496 							HAMMER2_COMP_NONE) +
1497 					      HAMMER2_ENC_CHECK(temp_check);
1498 			bcopy(bp->b_data, bdata, chain->bytes);
1499 
1500 			/*
1501 			 * Device buffer is now valid, chain is no
1502 			 * longer in the initial state.
1503 			 */
1504 			atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
1505 
1506 			if (ioflag & IO_SYNC) {
1507 				/*
1508 				 * Synchronous I/O requested.
1509 				 */
1510 				hammer2_io_bwrite(&dio);
1511 			/*
1512 			} else if ((ioflag & IO_DIRECT) &&
1513 				   loff + n == pblksize) {
1514 				hammer2_io_bdwrite(&dio);
1515 			*/
1516 			} else if (ioflag & IO_ASYNC) {
1517 				hammer2_io_bawrite(&dio);
1518 			} else {
1519 				hammer2_io_bdwrite(&dio);
1520 			}
1521 			break;
1522 		default:
1523 			panic("hammer2_write_bp: bad chain type %d\n",
1524 			      chain->bref.type);
1525 			/* NOT REACHED */
1526 			error = 0;
1527 			break;
1528 		}
1529 		KKASSERT(error == 0);	/* XXX TODO */
1530 	}
1531 	*errorp = error;
1532 }
1533 
1534 static
1535 int
1536 hammer2_remount(hammer2_mount_t *hmp, struct mount *mp, char *path,
1537 		struct vnode *devvp, struct ucred *cred)
1538 {
1539 	int error;
1540 
1541 	if (hmp->ronly && (mp->mnt_kern_flag & MNTK_WANTRDWR)) {
1542 		error = hammer2_recovery(hmp);
1543 	} else {
1544 		error = 0;
1545 	}
1546 	return error;
1547 }
1548 
1549 static
1550 int
1551 hammer2_vfs_unmount(struct mount *mp, int mntflags)
1552 {
1553 	hammer2_pfsmount_t *pmp;
1554 	hammer2_mount_t *hmp;
1555 	hammer2_chain_t *rchain;
1556 	hammer2_cluster_t *cluster;
1557 	int flags;
1558 	int error = 0;
1559 	int i;
1560 
1561 	pmp = MPTOPMP(mp);
1562 
1563 	if (pmp == NULL)
1564 		return(0);
1565 
1566 	lockmgr(&hammer2_mntlk, LK_EXCLUSIVE);
1567 	TAILQ_REMOVE(&hammer2_pfslist, pmp, mntentry);
1568 
1569 	/*
1570 	 * If mount initialization proceeded far enough we must flush
1571 	 * its vnodes.
1572 	 */
1573 	if (mntflags & MNT_FORCE)
1574 		flags = FORCECLOSE;
1575 	else
1576 		flags = 0;
1577 	if (pmp->iroot) {
1578 		error = vflush(mp, 0, flags);
1579 		if (error)
1580 			goto failed;
1581 	}
1582 
1583 	ccms_domain_uninit(&pmp->ccms_dom);
1584 
1585 	if (pmp->wthread_td) {
1586 		mtx_lock(&pmp->wthread_mtx);
1587 		pmp->wthread_destroy = 1;
1588 		wakeup(&pmp->wthread_bioq);
1589 		while (pmp->wthread_destroy != -1) {
1590 			mtxsleep(&pmp->wthread_destroy,
1591 				&pmp->wthread_mtx, 0,
1592 				"umount-sleep",	0);
1593 		}
1594 		mtx_unlock(&pmp->wthread_mtx);
1595 		pmp->wthread_td = NULL;
1596 	}
1597 
1598 	/*
1599 	 * Cleanup our reference on ihidden.
1600 	 */
1601 	if (pmp->ihidden) {
1602 		hammer2_inode_drop(pmp->ihidden);
1603 		pmp->ihidden = NULL;
1604 	}
1605 
1606 	/*
1607 	 * Cleanup our reference on iroot.  iroot is (should) not be needed
1608 	 * by the flush code.
1609 	 */
1610 	if (pmp->iroot) {
1611 		cluster = &pmp->iroot->cluster;
1612 		for (i = 0; i < pmp->iroot->cluster.nchains; ++i) {
1613 			rchain = pmp->iroot->cluster.array[i];
1614 			if (rchain == NULL)
1615 				continue;
1616 			hmp = rchain->hmp;
1617 			hammer2_vfs_unmount_hmp1(mp, hmp);
1618 
1619 			atomic_clear_int(&rchain->flags, HAMMER2_CHAIN_MOUNTED);
1620 #if REPORT_REFS_ERRORS
1621 			if (rchain->refs != 1)
1622 				kprintf("PMP->RCHAIN %p REFS WRONG %d\n",
1623 					rchain, rchain->refs);
1624 #else
1625 			KKASSERT(rchain->refs == 1);
1626 #endif
1627 			hammer2_chain_drop(rchain);
1628 			cluster->array[i] = NULL;
1629 			hammer2_vfs_unmount_hmp2(mp, hmp);
1630 		}
1631 		cluster->focus = NULL;
1632 
1633 #if REPORT_REFS_ERRORS
1634 		if (pmp->iroot->refs != 1)
1635 			kprintf("PMP->IROOT %p REFS WRONG %d\n",
1636 				pmp->iroot, pmp->iroot->refs);
1637 #else
1638 		KKASSERT(pmp->iroot->refs == 1);
1639 #endif
1640 		/* ref for pmp->iroot */
1641 		hammer2_inode_drop(pmp->iroot);
1642 		pmp->iroot = NULL;
1643 	}
1644 
1645 	pmp->mp = NULL;
1646 	mp->mnt_data = NULL;
1647 
1648 	kmalloc_destroy(&pmp->mmsg);
1649 	kmalloc_destroy(&pmp->minode);
1650 
1651 	kfree(pmp, M_HAMMER2);
1652 	error = 0;
1653 
1654 failed:
1655 	lockmgr(&hammer2_mntlk, LK_RELEASE);
1656 
1657 	return (error);
1658 }
1659 
1660 static
1661 void
1662 hammer2_vfs_unmount_hmp1(struct mount *mp, hammer2_mount_t *hmp)
1663 {
1664 	hammer2_mount_exlock(hmp);
1665 	--hmp->pmp_count;
1666 
1667 	kprintf("hammer2_unmount hmp=%p pmpcnt=%d\n", hmp, hmp->pmp_count);
1668 
1669 	kdmsg_iocom_uninit(&hmp->iocom);	/* XXX chain depend deadlck? */
1670 
1671 	/*
1672 	 * Flush any left over chains.  The voldata lock is only used
1673 	 * to synchronize against HAMMER2_CHAIN_MODIFIED_AUX.
1674 	 *
1675 	 * Flush twice to ensure that the freemap is completely
1676 	 * synchronized.  If we only do it once the next mount's
1677 	 * recovery scan will have to do some fixups (which isn't
1678 	 * bad, but we don't want it to have to do it except when
1679 	 * recovering from a crash).
1680 	 */
1681 	hammer2_voldata_lock(hmp);
1682 	if (((hmp->vchain.flags | hmp->fchain.flags) &
1683 	     HAMMER2_CHAIN_MODIFIED) ||
1684 	    hmp->vchain.update_xhi > hmp->vchain.update_xlo ||
1685 	    hmp->fchain.update_xhi > hmp->fchain.update_xlo) {
1686 		hammer2_voldata_unlock(hmp);
1687 		hammer2_vfs_sync(mp, MNT_WAIT);
1688 		/*hammer2_vfs_sync(mp, MNT_WAIT);*/
1689 	} else {
1690 		hammer2_voldata_unlock(hmp);
1691 	}
1692 	if (hmp->pmp_count == 0) {
1693 		if (((hmp->vchain.flags | hmp->fchain.flags) &
1694 		     HAMMER2_CHAIN_MODIFIED) ||
1695 		    hmp->vchain.update_xhi > hmp->vchain.update_xlo ||
1696 		    hmp->fchain.update_xhi > hmp->fchain.update_xlo) {
1697 			kprintf("hammer2_unmount: chains left over "
1698 				"after final sync\n");
1699 			kprintf("    vchain %08x update_xlo/hi %08x/%08x\n",
1700 				hmp->vchain.flags,
1701 				hmp->vchain.update_xlo,
1702 				hmp->vchain.update_xhi);
1703 			kprintf("    fchain %08x update_xhi/hi %08x/%08x\n",
1704 				hmp->fchain.flags,
1705 				hmp->fchain.update_xlo,
1706 				hmp->fchain.update_xhi);
1707 
1708 			if (hammer2_debug & 0x0010)
1709 				Debugger("entered debugger");
1710 		}
1711 	}
1712 }
1713 
1714 static
1715 void
1716 hammer2_vfs_unmount_hmp2(struct mount *mp, hammer2_mount_t *hmp)
1717 {
1718 	hammer2_pfsmount_t *spmp;
1719 	struct vnode *devvp;
1720 	int dumpcnt;
1721 	int ronly = ((mp->mnt_flag & MNT_RDONLY) != 0);
1722 
1723 	/*
1724 	 * If no PFS's left drop the master hammer2_mount for the
1725 	 * device.
1726 	 */
1727 	if (hmp->pmp_count == 0) {
1728 		/*
1729 		 * Clean up SPMP and the super-root inode
1730 		 */
1731 		spmp = hmp->spmp;
1732 		if (spmp) {
1733 			if (spmp->iroot) {
1734 				hammer2_inode_drop(spmp->iroot);
1735 				spmp->iroot = NULL;
1736 			}
1737 			hmp->spmp = NULL;
1738 			kmalloc_destroy(&spmp->mmsg);
1739 			kmalloc_destroy(&spmp->minode);
1740 			kfree(spmp, M_HAMMER2);
1741 		}
1742 
1743 		/*
1744 		 * Finish up with the device vnode
1745 		 */
1746 		if ((devvp = hmp->devvp) != NULL) {
1747 			vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
1748 			vinvalbuf(devvp, (ronly ? 0 : V_SAVE), 0, 0);
1749 			hmp->devvp = NULL;
1750 			VOP_CLOSE(devvp, (ronly ? FREAD : FREAD|FWRITE), NULL);
1751 			vn_unlock(devvp);
1752 			vrele(devvp);
1753 			devvp = NULL;
1754 		}
1755 
1756 		/*
1757 		 * Clear vchain/fchain flags that might prevent final cleanup
1758 		 * of these chains.
1759 		 */
1760 		if (hmp->vchain.flags & HAMMER2_CHAIN_MODIFIED) {
1761 			atomic_clear_int(&hmp->vchain.flags,
1762 					 HAMMER2_CHAIN_MODIFIED);
1763 			hammer2_chain_drop(&hmp->vchain);
1764 		}
1765 		if (hmp->vchain.flags & HAMMER2_CHAIN_FLUSH_CREATE) {
1766 			atomic_clear_int(&hmp->vchain.flags,
1767 					 HAMMER2_CHAIN_FLUSH_CREATE);
1768 			hammer2_chain_drop(&hmp->vchain);
1769 		}
1770 		if (hmp->vchain.flags & HAMMER2_CHAIN_FLUSH_DELETE) {
1771 			atomic_clear_int(&hmp->vchain.flags,
1772 					 HAMMER2_CHAIN_FLUSH_DELETE);
1773 			hammer2_chain_drop(&hmp->vchain);
1774 		}
1775 
1776 		if (hmp->fchain.flags & HAMMER2_CHAIN_MODIFIED) {
1777 			atomic_clear_int(&hmp->fchain.flags,
1778 					 HAMMER2_CHAIN_MODIFIED);
1779 			hammer2_chain_drop(&hmp->fchain);
1780 		}
1781 		if (hmp->fchain.flags & HAMMER2_CHAIN_FLUSH_CREATE) {
1782 			atomic_clear_int(&hmp->fchain.flags,
1783 					 HAMMER2_CHAIN_FLUSH_CREATE);
1784 			hammer2_chain_drop(&hmp->fchain);
1785 		}
1786 		if (hmp->fchain.flags & HAMMER2_CHAIN_FLUSH_DELETE) {
1787 			atomic_clear_int(&hmp->fchain.flags,
1788 					 HAMMER2_CHAIN_FLUSH_DELETE);
1789 			hammer2_chain_drop(&hmp->fchain);
1790 		}
1791 
1792 		/*
1793 		 * Final drop of embedded freemap root chain to
1794 		 * clean up fchain.core (fchain structure is not
1795 		 * flagged ALLOCATED so it is cleaned out and then
1796 		 * left to rot).
1797 		 */
1798 		hammer2_chain_drop(&hmp->fchain);
1799 
1800 		/*
1801 		 * Final drop of embedded volume root chain to clean
1802 		 * up vchain.core (vchain structure is not flagged
1803 		 * ALLOCATED so it is cleaned out and then left to
1804 		 * rot).
1805 		 */
1806 		dumpcnt = 50;
1807 		hammer2_dump_chain(&hmp->vchain, 0, &dumpcnt, 'v');
1808 		dumpcnt = 50;
1809 		hammer2_dump_chain(&hmp->fchain, 0, &dumpcnt, 'f');
1810 		hammer2_mount_unlock(hmp);
1811 		hammer2_chain_drop(&hmp->vchain);
1812 
1813 		hammer2_io_cleanup(hmp, &hmp->iotree);
1814 		if (hmp->iofree_count) {
1815 			kprintf("io_cleanup: %d I/O's left hanging\n",
1816 				hmp->iofree_count);
1817 		}
1818 
1819 		TAILQ_REMOVE(&hammer2_mntlist, hmp, mntentry);
1820 		kmalloc_destroy(&hmp->mchain);
1821 		kfree(hmp, M_HAMMER2);
1822 	} else {
1823 		hammer2_mount_unlock(hmp);
1824 	}
1825 }
1826 
1827 static
1828 int
1829 hammer2_vfs_vget(struct mount *mp, struct vnode *dvp,
1830 	     ino_t ino, struct vnode **vpp)
1831 {
1832 	kprintf("hammer2_vget\n");
1833 	return (EOPNOTSUPP);
1834 }
1835 
1836 static
1837 int
1838 hammer2_vfs_root(struct mount *mp, struct vnode **vpp)
1839 {
1840 	hammer2_pfsmount_t *pmp;
1841 	hammer2_cluster_t *cparent;
1842 	int error;
1843 	struct vnode *vp;
1844 
1845 	pmp = MPTOPMP(mp);
1846 	if (pmp->iroot == NULL) {
1847 		*vpp = NULL;
1848 		error = EINVAL;
1849 	} else {
1850 		cparent = hammer2_inode_lock_sh(pmp->iroot);
1851 		vp = hammer2_igetv(pmp->iroot, cparent, &error);
1852 		hammer2_inode_unlock_sh(pmp->iroot, cparent);
1853 		*vpp = vp;
1854 		if (vp == NULL)
1855 			kprintf("vnodefail\n");
1856 	}
1857 
1858 	return (error);
1859 }
1860 
1861 /*
1862  * Filesystem status
1863  *
1864  * XXX incorporate ipdata->inode_quota and data_quota
1865  */
1866 static
1867 int
1868 hammer2_vfs_statfs(struct mount *mp, struct statfs *sbp, struct ucred *cred)
1869 {
1870 	hammer2_pfsmount_t *pmp;
1871 	hammer2_mount_t *hmp;
1872 
1873 	pmp = MPTOPMP(mp);
1874 	KKASSERT(pmp->iroot->cluster.nchains >= 1);
1875 	hmp = pmp->iroot->cluster.focus->hmp;	/* XXX */
1876 
1877 	mp->mnt_stat.f_files = pmp->inode_count;
1878 	mp->mnt_stat.f_ffree = 0;
1879 	mp->mnt_stat.f_blocks = hmp->voldata.allocator_size / HAMMER2_PBUFSIZE;
1880 	mp->mnt_stat.f_bfree =  hmp->voldata.allocator_free / HAMMER2_PBUFSIZE;
1881 	mp->mnt_stat.f_bavail = mp->mnt_stat.f_bfree;
1882 
1883 	*sbp = mp->mnt_stat;
1884 	return (0);
1885 }
1886 
1887 static
1888 int
1889 hammer2_vfs_statvfs(struct mount *mp, struct statvfs *sbp, struct ucred *cred)
1890 {
1891 	hammer2_pfsmount_t *pmp;
1892 	hammer2_mount_t *hmp;
1893 
1894 	pmp = MPTOPMP(mp);
1895 	KKASSERT(pmp->iroot->cluster.nchains >= 1);
1896 	hmp = pmp->iroot->cluster.focus->hmp;	/* XXX */
1897 
1898 	mp->mnt_vstat.f_bsize = HAMMER2_PBUFSIZE;
1899 	mp->mnt_vstat.f_files = pmp->inode_count;
1900 	mp->mnt_vstat.f_ffree = 0;
1901 	mp->mnt_vstat.f_blocks = hmp->voldata.allocator_size / HAMMER2_PBUFSIZE;
1902 	mp->mnt_vstat.f_bfree =  hmp->voldata.allocator_free / HAMMER2_PBUFSIZE;
1903 	mp->mnt_vstat.f_bavail = mp->mnt_vstat.f_bfree;
1904 
1905 	*sbp = mp->mnt_vstat;
1906 	return (0);
1907 }
1908 
1909 /*
1910  * Mount-time recovery (RW mounts)
1911  *
1912  * Updates to the free block table are allowed to lag flushes by one
1913  * transaction.  In case of a crash, then on a fresh mount we must do an
1914  * incremental scan of the last committed transaction id and make sure that
1915  * all related blocks have been marked allocated.
1916  *
1917  * The super-root topology and each PFS has its own transaction id domain,
1918  * so we must track PFS boundary transitions.
1919  */
1920 struct hammer2_recovery_elm {
1921 	TAILQ_ENTRY(hammer2_recovery_elm) entry;
1922 	hammer2_chain_t *chain;
1923 	hammer2_tid_t sync_tid;
1924 };
1925 
1926 TAILQ_HEAD(hammer2_recovery_list, hammer2_recovery_elm);
1927 
1928 struct hammer2_recovery_info {
1929 	struct hammer2_recovery_list list;
1930 	int	depth;
1931 };
1932 
1933 static int hammer2_recovery_scan(hammer2_trans_t *trans, hammer2_mount_t *hmp,
1934 			hammer2_chain_t *parent,
1935 			struct hammer2_recovery_info *info,
1936 			hammer2_tid_t sync_tid);
1937 
1938 #define HAMMER2_RECOVERY_MAXDEPTH	10
1939 
1940 static
1941 int
1942 hammer2_recovery(hammer2_mount_t *hmp)
1943 {
1944 	hammer2_trans_t trans;
1945 	struct hammer2_recovery_info info;
1946 	struct hammer2_recovery_elm *elm;
1947 	hammer2_chain_t *parent;
1948 	hammer2_tid_t sync_tid;
1949 	int error;
1950 	int cumulative_error = 0;
1951 
1952 	hammer2_trans_init(&trans, hmp->spmp, 0);
1953 
1954 	sync_tid = 0;
1955 	TAILQ_INIT(&info.list);
1956 	info.depth = 0;
1957 	parent = hammer2_chain_lookup_init(&hmp->vchain, 0);
1958 	cumulative_error = hammer2_recovery_scan(&trans, hmp, parent,
1959 						 &info, sync_tid);
1960 	hammer2_chain_lookup_done(parent);
1961 
1962 	while ((elm = TAILQ_FIRST(&info.list)) != NULL) {
1963 		TAILQ_REMOVE(&info.list, elm, entry);
1964 		parent = elm->chain;
1965 		sync_tid = elm->sync_tid;
1966 		kfree(elm, M_HAMMER2);
1967 
1968 		hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS |
1969 					   HAMMER2_RESOLVE_NOREF);
1970 		error = hammer2_recovery_scan(&trans, hmp, parent,
1971 					      &info, sync_tid);
1972 		hammer2_chain_unlock(parent);
1973 		if (error)
1974 			cumulative_error = error;
1975 	}
1976 	hammer2_trans_done(&trans);
1977 
1978 	return cumulative_error;
1979 }
1980 
1981 static
1982 int
1983 hammer2_recovery_scan(hammer2_trans_t *trans, hammer2_mount_t *hmp,
1984 		      hammer2_chain_t *parent,
1985 		      struct hammer2_recovery_info *info,
1986 		      hammer2_tid_t sync_tid)
1987 {
1988 	hammer2_chain_t *chain;
1989 	int cache_index;
1990 	int cumulative_error = 0;
1991 	int pfs_boundary = 0;
1992 	int error;
1993 
1994 	/*
1995 	 * Adjust freemap to ensure that the block(s) are marked allocated.
1996 	 */
1997 	if (parent->bref.type != HAMMER2_BREF_TYPE_VOLUME) {
1998 		hammer2_freemap_adjust(trans, hmp, &parent->bref,
1999 				       HAMMER2_FREEMAP_DORECOVER);
2000 	}
2001 
2002 	/*
2003 	 * Check type for recursive scan
2004 	 */
2005 	switch(parent->bref.type) {
2006 	case HAMMER2_BREF_TYPE_VOLUME:
2007 		/* data already instantiated */
2008 		break;
2009 	case HAMMER2_BREF_TYPE_INODE:
2010 		/*
2011 		 * Must instantiate data for DIRECTDATA test and also
2012 		 * for recursion.
2013 		 */
2014 		hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
2015 		if (parent->data->ipdata.op_flags & HAMMER2_OPFLAG_DIRECTDATA) {
2016 			/* not applicable to recovery scan */
2017 			hammer2_chain_unlock(parent);
2018 			return 0;
2019 		}
2020 		if ((parent->data->ipdata.op_flags & HAMMER2_OPFLAG_PFSROOT) &&
2021 		    info->depth != 0) {
2022 			pfs_boundary = 1;
2023 			sync_tid = parent->bref.mirror_tid - 1;
2024 		}
2025 		hammer2_chain_unlock(parent);
2026 		break;
2027 	case HAMMER2_BREF_TYPE_INDIRECT:
2028 		/*
2029 		 * Must instantiate data for recursion
2030 		 */
2031 		hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
2032 		hammer2_chain_unlock(parent);
2033 		break;
2034 	case HAMMER2_BREF_TYPE_DATA:
2035 	case HAMMER2_BREF_TYPE_FREEMAP:
2036 	case HAMMER2_BREF_TYPE_FREEMAP_NODE:
2037 	case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
2038 		/* not applicable to recovery scan */
2039 		return 0;
2040 		break;
2041 	default:
2042 		return EDOM;
2043 	}
2044 
2045 	/*
2046 	 * Defer operation if depth limit reached or if we are crossing a
2047 	 * PFS boundary.
2048 	 */
2049 	if (info->depth >= HAMMER2_RECOVERY_MAXDEPTH || pfs_boundary) {
2050 		struct hammer2_recovery_elm *elm;
2051 
2052 		elm = kmalloc(sizeof(*elm), M_HAMMER2, M_ZERO | M_WAITOK);
2053 		elm->chain = parent;
2054 		elm->sync_tid = sync_tid;
2055 		hammer2_chain_ref(parent);
2056 		TAILQ_INSERT_TAIL(&info->list, elm, entry);
2057 		/* unlocked by caller */
2058 
2059 		return(0);
2060 	}
2061 
2062 
2063 	/*
2064 	 * Recursive scan of the last flushed transaction only.  We are
2065 	 * doing this without pmp assignments so don't leave the chains
2066 	 * hanging around after we are done with them.
2067 	 */
2068 	cache_index = 0;
2069 	chain = hammer2_chain_scan(parent, NULL, &cache_index,
2070 				   HAMMER2_LOOKUP_NODATA);
2071 	while (chain) {
2072 		atomic_set_int(&chain->flags, HAMMER2_CHAIN_RELEASE);
2073 		if (chain->bref.mirror_tid >= sync_tid) {
2074 			++info->depth;
2075 			error = hammer2_recovery_scan(trans, hmp, chain,
2076 						      info, sync_tid);
2077 			--info->depth;
2078 			if (error)
2079 				cumulative_error = error;
2080 		}
2081 		chain = hammer2_chain_scan(parent, chain, &cache_index,
2082 					   HAMMER2_LOOKUP_NODATA);
2083 	}
2084 
2085 	return cumulative_error;
2086 }
2087 
2088 /*
2089  * Sync the entire filesystem; this is called from the filesystem syncer
2090  * process periodically and whenever a user calls sync(1) on the hammer
2091  * mountpoint.
2092  *
2093  * Currently is actually called from the syncer! \o/
2094  *
2095  * This task will have to snapshot the state of the dirty inode chain.
2096  * From that, it will have to make sure all of the inodes on the dirty
2097  * chain have IO initiated. We make sure that io is initiated for the root
2098  * block.
2099  *
2100  * If waitfor is set, we wait for media to acknowledge the new rootblock.
2101  *
2102  * THINKS: side A vs side B, to have sync not stall all I/O?
2103  */
2104 int
2105 hammer2_vfs_sync(struct mount *mp, int waitfor)
2106 {
2107 	struct hammer2_sync_info info;
2108 	hammer2_inode_t *iroot;
2109 	hammer2_chain_t *chain;
2110 	hammer2_chain_t *parent;
2111 	hammer2_pfsmount_t *pmp;
2112 	hammer2_mount_t *hmp;
2113 	int flags;
2114 	int error;
2115 	int total_error;
2116 	int force_fchain;
2117 	int i;
2118 	int j;
2119 
2120 	pmp = MPTOPMP(mp);
2121 	iroot = pmp->iroot;
2122 	KKASSERT(iroot);
2123 	KKASSERT(iroot->pmp == pmp);
2124 
2125 	/*
2126 	 * We can't acquire locks on existing vnodes while in a transaction
2127 	 * without risking a deadlock.  This assumes that vfsync() can be
2128 	 * called without the vnode locked (which it can in DragonFly).
2129 	 * Otherwise we'd have to implement a multi-pass or flag the lock
2130 	 * failures and retry.
2131 	 *
2132 	 * The reclamation code interlocks with the sync list's token
2133 	 * (by removing the vnode from the scan list) before unlocking
2134 	 * the inode, giving us time to ref the inode.
2135 	 */
2136 	/*flags = VMSC_GETVP;*/
2137 	flags = 0;
2138 	if (waitfor & MNT_LAZY)
2139 		flags |= VMSC_ONEPASS;
2140 
2141 	/*
2142 	 * Start our flush transaction.  This does not return until all
2143 	 * concurrent transactions have completed and will prevent any
2144 	 * new transactions from running concurrently, except for the
2145 	 * buffer cache transactions.
2146 	 *
2147 	 * For efficiency do an async pass before making sure with a
2148 	 * synchronous pass on all related buffer cache buffers.  It
2149 	 * should theoretically not be possible for any new file buffers
2150 	 * to be instantiated during this sequence.
2151 	 */
2152 	hammer2_trans_init(&info.trans, pmp, HAMMER2_TRANS_ISFLUSH |
2153 					     HAMMER2_TRANS_PREFLUSH);
2154 	hammer2_run_unlinkq(&info.trans, pmp);
2155 
2156 	info.error = 0;
2157 	info.waitfor = MNT_NOWAIT;
2158 	vsyncscan(mp, flags | VMSC_NOWAIT, hammer2_sync_scan2, &info);
2159 	info.waitfor = MNT_WAIT;
2160 	vsyncscan(mp, flags, hammer2_sync_scan2, &info);
2161 
2162 	/*
2163 	 * Clear PREFLUSH.  This prevents (or asserts on) any new logical
2164 	 * buffer cache flushes which occur during the flush.  Device buffers
2165 	 * are not affected.
2166 	 */
2167 
2168 #if 0
2169 	if (info.error == 0 && (waitfor & MNT_WAIT)) {
2170 		info.waitfor = waitfor;
2171 		    vsyncscan(mp, flags, hammer2_sync_scan2, &info);
2172 
2173 	}
2174 #endif
2175 	hammer2_bioq_sync(info.trans.pmp);
2176 	atomic_clear_int(&info.trans.flags, HAMMER2_TRANS_PREFLUSH);
2177 
2178 	total_error = 0;
2179 
2180 	/*
2181 	 * Flush all storage elements making up the cluster
2182 	 *
2183 	 * We must also flush any deleted siblings because the super-root
2184 	 * flush won't do it for us.  They all must be staged or the
2185 	 * super-root flush will not be able to update its block table
2186 	 * properly.
2187 	 *
2188 	 * XXX currently done serially instead of concurrently
2189 	 */
2190 	for (i = 0; iroot && i < iroot->cluster.nchains; ++i) {
2191 		chain = iroot->cluster.array[i];
2192 		if (chain) {
2193 			hammer2_chain_lock(chain, HAMMER2_RESOLVE_ALWAYS);
2194 			hammer2_flush(&info.trans, &chain);
2195 			hammer2_chain_unlock(chain);
2196 		}
2197 		if (chain) {
2198 			hammer2_chain_t *nchain;
2199 			chain = TAILQ_FIRST(&chain->core->ownerq);
2200 			hammer2_chain_ref(chain);
2201 			while (chain) {
2202 				hammer2_chain_lock(chain,
2203 						   HAMMER2_RESOLVE_ALWAYS);
2204 				hammer2_flush(&info.trans, &chain);
2205 				hammer2_chain_unlock(chain);
2206 				nchain = TAILQ_NEXT(chain, core_entry);
2207 				if (nchain)
2208 					hammer2_chain_ref(nchain);
2209 				hammer2_chain_drop(chain);
2210 				chain = nchain;
2211 			}
2212 		}
2213 	}
2214 #if 0
2215 	hammer2_trans_done(&info.trans);
2216 #endif
2217 
2218 	/*
2219 	 * Flush all volume roots to synchronize PFS flushes with the
2220 	 * storage media.  Use a super-root transaction for each one.
2221 	 *
2222 	 * The flush code will detect super-root -> pfs-root chain
2223 	 * transitions using the last pfs-root flush.
2224 	 */
2225 	for (i = 0; iroot && i < iroot->cluster.nchains; ++i) {
2226 		chain = iroot->cluster.array[i];
2227 		if (chain == NULL)
2228 			continue;
2229 
2230 		hmp = chain->hmp;
2231 
2232 		/*
2233 		 * We only have to flush each hmp once
2234 		 */
2235 		for (j = i - 1; j >= 0; --j) {
2236 			if (iroot->cluster.array[j] &&
2237 			    iroot->cluster.array[j]->hmp == hmp)
2238 				break;
2239 		}
2240 		if (j >= 0)
2241 			continue;
2242 		hammer2_trans_spmp(&info.trans, hmp->spmp);
2243 
2244 		/*
2245 		 * Force an update of the XID from the PFS root to the
2246 		 * topology root.  We couldn't do this from the PFS
2247 		 * transaction because a SPMP transaction is needed.
2248 		 * This does not modify blocks, instead what it does is
2249 		 * allow the flush code to find the transition point and
2250 		 * then update on the way back up.
2251 		 */
2252 		parent = TAILQ_LAST(&chain->above->ownerq, h2_core_list);
2253 		KKASSERT(chain->pmp != parent->pmp);
2254 		hammer2_chain_setsubmod(&info.trans, parent);
2255 
2256 		/*
2257 		 * Media mounts have two 'roots', vchain for the topology
2258 		 * and fchain for the free block table.  Flush both.
2259 		 *
2260 		 * Note that the topology and free block table are handled
2261 		 * independently, so the free block table can wind up being
2262 		 * ahead of the topology.  We depend on the bulk free scan
2263 		 * code to deal with any loose ends.
2264 		 */
2265 		hammer2_chain_lock(&hmp->vchain, HAMMER2_RESOLVE_ALWAYS);
2266 		hammer2_chain_lock(&hmp->fchain, HAMMER2_RESOLVE_ALWAYS);
2267 		if ((hmp->fchain.flags & HAMMER2_CHAIN_MODIFIED) ||
2268 		    hmp->fchain.update_xhi > hmp->fchain.update_xlo) {
2269 			/*
2270 			 * This will also modify vchain as a side effect,
2271 			 * mark vchain as modified now.
2272 			 */
2273 			hammer2_voldata_modify(hmp);
2274 			chain = &hmp->fchain;
2275 			hammer2_flush(&info.trans, &chain);
2276 			KKASSERT(chain == &hmp->fchain);
2277 		}
2278 		hammer2_chain_unlock(&hmp->fchain);
2279 		hammer2_chain_unlock(&hmp->vchain);
2280 
2281 		hammer2_chain_lock(&hmp->vchain, HAMMER2_RESOLVE_ALWAYS);
2282 		if ((hmp->vchain.flags & HAMMER2_CHAIN_MODIFIED) ||
2283 		    hmp->vchain.update_xhi > hmp->vchain.update_xlo) {
2284 			chain = &hmp->vchain;
2285 			hammer2_flush(&info.trans, &chain);
2286 			KKASSERT(chain == &hmp->vchain);
2287 			force_fchain = 1;
2288 		} else {
2289 			force_fchain = 0;
2290 		}
2291 		hammer2_chain_unlock(&hmp->vchain);
2292 
2293 #if 0
2294 		hammer2_chain_lock(&hmp->fchain, HAMMER2_RESOLVE_ALWAYS);
2295 		if ((hmp->fchain.flags & HAMMER2_CHAIN_MODIFIED) ||
2296 		    hmp->fchain.update_xhi > hmp->fchain.update_xlo ||
2297 		    force_fchain) {
2298 			/* this will also modify vchain as a side effect */
2299 			chain = &hmp->fchain;
2300 			hammer2_flush(&info.trans, &chain);
2301 			KKASSERT(chain == &hmp->fchain);
2302 		}
2303 		hammer2_chain_unlock(&hmp->fchain);
2304 #endif
2305 
2306 		error = 0;
2307 
2308 		/*
2309 		 * We can't safely flush the volume header until we have
2310 		 * flushed any device buffers which have built up.
2311 		 *
2312 		 * XXX this isn't being incremental
2313 		 */
2314 		vn_lock(hmp->devvp, LK_EXCLUSIVE | LK_RETRY);
2315 		error = VOP_FSYNC(hmp->devvp, MNT_WAIT, 0);
2316 		vn_unlock(hmp->devvp);
2317 
2318 		/*
2319 		 * The flush code sets CHAIN_VOLUMESYNC to indicate that the
2320 		 * volume header needs synchronization via hmp->volsync.
2321 		 *
2322 		 * XXX synchronize the flag & data with only this flush XXX
2323 		 */
2324 		if (error == 0 &&
2325 		    (hmp->vchain.flags & HAMMER2_CHAIN_VOLUMESYNC)) {
2326 			struct buf *bp;
2327 
2328 			/*
2329 			 * Synchronize the disk before flushing the volume
2330 			 * header.
2331 			 */
2332 			bp = getpbuf(NULL);
2333 			bp->b_bio1.bio_offset = 0;
2334 			bp->b_bufsize = 0;
2335 			bp->b_bcount = 0;
2336 			bp->b_cmd = BUF_CMD_FLUSH;
2337 			bp->b_bio1.bio_done = biodone_sync;
2338 			bp->b_bio1.bio_flags |= BIO_SYNC;
2339 			vn_strategy(hmp->devvp, &bp->b_bio1);
2340 			biowait(&bp->b_bio1, "h2vol");
2341 			relpbuf(bp, NULL);
2342 
2343 			/*
2344 			 * Then we can safely flush the version of the
2345 			 * volume header synchronized by the flush code.
2346 			 */
2347 			i = hmp->volhdrno + 1;
2348 			if (i >= HAMMER2_NUM_VOLHDRS)
2349 				i = 0;
2350 			if (i * HAMMER2_ZONE_BYTES64 + HAMMER2_SEGSIZE >
2351 			    hmp->volsync.volu_size) {
2352 				i = 0;
2353 			}
2354 			kprintf("sync volhdr %d %jd\n",
2355 				i, (intmax_t)hmp->volsync.volu_size);
2356 			bp = getblk(hmp->devvp, i * HAMMER2_ZONE_BYTES64,
2357 				    HAMMER2_PBUFSIZE, 0, 0);
2358 			atomic_clear_int(&hmp->vchain.flags,
2359 					 HAMMER2_CHAIN_VOLUMESYNC);
2360 			bcopy(&hmp->volsync, bp->b_data, HAMMER2_PBUFSIZE);
2361 			bawrite(bp);
2362 			hmp->volhdrno = i;
2363 		}
2364 		if (error)
2365 			total_error = error;
2366 
2367 #if 0
2368 		hammer2_trans_done(&info.trans);
2369 #endif
2370 	}
2371 	hammer2_trans_done(&info.trans);
2372 
2373 	return (total_error);
2374 }
2375 
2376 /*
2377  * Sync passes.
2378  */
2379 static int
2380 hammer2_sync_scan2(struct mount *mp, struct vnode *vp, void *data)
2381 {
2382 	struct hammer2_sync_info *info = data;
2383 	hammer2_inode_t *ip;
2384 	int error;
2385 
2386 	/*
2387 	 *
2388 	 */
2389 	ip = VTOI(vp);
2390 	if (ip == NULL)
2391 		return(0);
2392 	if (vp->v_type == VNON || vp->v_type == VBAD) {
2393 		vclrisdirty(vp);
2394 		return(0);
2395 	}
2396 	if ((ip->flags & HAMMER2_INODE_MODIFIED) == 0 &&
2397 	    RB_EMPTY(&vp->v_rbdirty_tree)) {
2398 		vclrisdirty(vp);
2399 		return(0);
2400 	}
2401 
2402 	/*
2403 	 * VOP_FSYNC will start a new transaction so replicate some code
2404 	 * here to do it inline (see hammer2_vop_fsync()).
2405 	 *
2406 	 * WARNING: The vfsync interacts with the buffer cache and might
2407 	 *          block, we can't hold the inode lock at that time.
2408 	 *	    However, we MUST ref ip before blocking to ensure that
2409 	 *	    it isn't ripped out from under us (since we do not
2410 	 *	    hold a lock on the vnode).
2411 	 */
2412 	hammer2_inode_ref(ip);
2413 	atomic_clear_int(&ip->flags, HAMMER2_INODE_MODIFIED);
2414 	if (vp)
2415 		vfsync(vp, MNT_NOWAIT, 1, NULL, NULL);
2416 
2417 	hammer2_inode_drop(ip);
2418 #if 1
2419 	error = 0;
2420 	if (error)
2421 		info->error = error;
2422 #endif
2423 	return(0);
2424 }
2425 
2426 static
2427 int
2428 hammer2_vfs_vptofh(struct vnode *vp, struct fid *fhp)
2429 {
2430 	return (0);
2431 }
2432 
2433 static
2434 int
2435 hammer2_vfs_fhtovp(struct mount *mp, struct vnode *rootvp,
2436 	       struct fid *fhp, struct vnode **vpp)
2437 {
2438 	return (0);
2439 }
2440 
2441 static
2442 int
2443 hammer2_vfs_checkexp(struct mount *mp, struct sockaddr *nam,
2444 		 int *exflagsp, struct ucred **credanonp)
2445 {
2446 	return (0);
2447 }
2448 
2449 /*
2450  * Support code for hammer2_mount().  Read, verify, and install the volume
2451  * header into the HMP
2452  *
2453  * XXX read four volhdrs and use the one with the highest TID whos CRC
2454  *     matches.
2455  *
2456  * XXX check iCRCs.
2457  *
2458  * XXX For filesystems w/ less than 4 volhdrs, make sure to not write to
2459  *     nonexistant locations.
2460  *
2461  * XXX Record selected volhdr and ring updates to each of 4 volhdrs
2462  */
2463 static
2464 int
2465 hammer2_install_volume_header(hammer2_mount_t *hmp)
2466 {
2467 	hammer2_volume_data_t *vd;
2468 	struct buf *bp;
2469 	hammer2_crc32_t crc0, crc, bcrc0, bcrc;
2470 	int error_reported;
2471 	int error;
2472 	int valid;
2473 	int i;
2474 
2475 	error_reported = 0;
2476 	error = 0;
2477 	valid = 0;
2478 	bp = NULL;
2479 
2480 	/*
2481 	 * There are up to 4 copies of the volume header (syncs iterate
2482 	 * between them so there is no single master).  We don't trust the
2483 	 * volu_size field so we don't know precisely how large the filesystem
2484 	 * is, so depend on the OS to return an error if we go beyond the
2485 	 * block device's EOF.
2486 	 */
2487 	for (i = 0; i < HAMMER2_NUM_VOLHDRS; i++) {
2488 		error = bread(hmp->devvp, i * HAMMER2_ZONE_BYTES64,
2489 			      HAMMER2_VOLUME_BYTES, &bp);
2490 		if (error) {
2491 			brelse(bp);
2492 			bp = NULL;
2493 			continue;
2494 		}
2495 
2496 		vd = (struct hammer2_volume_data *) bp->b_data;
2497 		if ((vd->magic != HAMMER2_VOLUME_ID_HBO) &&
2498 		    (vd->magic != HAMMER2_VOLUME_ID_ABO)) {
2499 			brelse(bp);
2500 			bp = NULL;
2501 			continue;
2502 		}
2503 
2504 		if (vd->magic == HAMMER2_VOLUME_ID_ABO) {
2505 			/* XXX: Reversed-endianness filesystem */
2506 			kprintf("hammer2: reverse-endian filesystem detected");
2507 			brelse(bp);
2508 			bp = NULL;
2509 			continue;
2510 		}
2511 
2512 		crc = vd->icrc_sects[HAMMER2_VOL_ICRC_SECT0];
2513 		crc0 = hammer2_icrc32(bp->b_data + HAMMER2_VOLUME_ICRC0_OFF,
2514 				      HAMMER2_VOLUME_ICRC0_SIZE);
2515 		bcrc = vd->icrc_sects[HAMMER2_VOL_ICRC_SECT1];
2516 		bcrc0 = hammer2_icrc32(bp->b_data + HAMMER2_VOLUME_ICRC1_OFF,
2517 				       HAMMER2_VOLUME_ICRC1_SIZE);
2518 		if ((crc0 != crc) || (bcrc0 != bcrc)) {
2519 			kprintf("hammer2 volume header crc "
2520 				"mismatch copy #%d %08x/%08x\n",
2521 				i, crc0, crc);
2522 			error_reported = 1;
2523 			brelse(bp);
2524 			bp = NULL;
2525 			continue;
2526 		}
2527 		if (valid == 0 || hmp->voldata.mirror_tid < vd->mirror_tid) {
2528 			valid = 1;
2529 			hmp->voldata = *vd;
2530 			hmp->volhdrno = i;
2531 		}
2532 		brelse(bp);
2533 		bp = NULL;
2534 	}
2535 	if (valid) {
2536 		hmp->volsync = hmp->voldata;
2537 		error = 0;
2538 		if (error_reported || bootverbose || 1) { /* 1/DEBUG */
2539 			kprintf("hammer2: using volume header #%d\n",
2540 				hmp->volhdrno);
2541 		}
2542 	} else {
2543 		error = EINVAL;
2544 		kprintf("hammer2: no valid volume headers found!\n");
2545 	}
2546 	return (error);
2547 }
2548 
2549 /*
2550  * Reconnect using the passed file pointer.  The caller must ref the
2551  * fp for us.
2552  */
2553 void
2554 hammer2_cluster_reconnect(hammer2_mount_t *hmp, struct file *fp)
2555 {
2556 	size_t name_len;
2557 	const char *name = "disk-volume";
2558 
2559 	/*
2560 	 * Closes old comm descriptor, kills threads, cleans up
2561 	 * states, then installs the new descriptor and creates
2562 	 * new threads.
2563 	 */
2564 	kdmsg_iocom_reconnect(&hmp->iocom, fp, "hammer2");
2565 
2566 	/*
2567 	 * Setup LNK_CONN fields for autoinitiated state machine.  We
2568 	 * will use SPANs to advertise multiple PFSs so only pass the
2569 	 * fsid and HAMMER2_PFSTYPE_SUPROOT for the AUTOCONN.
2570 	 *
2571 	 * We are not initiating a LNK_SPAN so we do not have to set-up
2572 	 * iocom.auto_lnk_span.
2573 	 */
2574 	bzero(&hmp->iocom.auto_lnk_conn.pfs_clid,
2575 	      sizeof(hmp->iocom.auto_lnk_conn.pfs_clid));
2576 	hmp->iocom.auto_lnk_conn.pfs_fsid = hmp->voldata.fsid;
2577 	hmp->iocom.auto_lnk_conn.pfs_type = HAMMER2_PFSTYPE_SUPROOT;
2578 	hmp->iocom.auto_lnk_conn.proto_version = DMSG_SPAN_PROTO_1;
2579 #if 0
2580 	hmp->iocom.auto_lnk_conn.peer_type = hmp->voldata.peer_type;
2581 #endif
2582 	hmp->iocom.auto_lnk_conn.peer_type = DMSG_PEER_HAMMER2;
2583 
2584 	/*
2585 	 * Filter adjustment.  Clients do not need visibility into other
2586 	 * clients (otherwise millions of clients would present a serious
2587 	 * problem).  The fs_label also serves to restrict the namespace.
2588 	 */
2589 	hmp->iocom.auto_lnk_conn.peer_mask = 1LLU << DMSG_PEER_HAMMER2;
2590 	hmp->iocom.auto_lnk_conn.pfs_mask = (uint64_t)-1;
2591 
2592 #if 0
2593 	switch (ipdata->pfs_type) {
2594 	case DMSG_PFSTYPE_CLIENT:
2595 		hmp->iocom.auto_lnk_conn.peer_mask &=
2596 				~(1LLU << DMSG_PFSTYPE_CLIENT);
2597 		break;
2598 	default:
2599 		break;
2600 	}
2601 #endif
2602 
2603 	name_len = strlen(name);
2604 	if (name_len >= sizeof(hmp->iocom.auto_lnk_conn.fs_label))
2605 		name_len = sizeof(hmp->iocom.auto_lnk_conn.fs_label) - 1;
2606 	bcopy(name, hmp->iocom.auto_lnk_conn.fs_label, name_len);
2607 	hmp->iocom.auto_lnk_conn.fs_label[name_len] = 0;
2608 
2609 	kdmsg_iocom_autoinitiate(&hmp->iocom, hammer2_autodmsg);
2610 }
2611 
2612 static int
2613 hammer2_rcvdmsg(kdmsg_msg_t *msg)
2614 {
2615 	kprintf("RCVMSG %08x\n", msg->tcmd);
2616 
2617 	switch(msg->tcmd) {
2618 	case DMSG_DBG_SHELL:
2619 		/*
2620 		 * (non-transaction)
2621 		 * Execute shell command (not supported atm)
2622 		 */
2623 		kdmsg_msg_result(msg, DMSG_ERR_NOSUPP);
2624 		break;
2625 	case DMSG_DBG_SHELL | DMSGF_REPLY:
2626 		/*
2627 		 * (non-transaction)
2628 		 */
2629 		if (msg->aux_data) {
2630 			msg->aux_data[msg->aux_size - 1] = 0;
2631 			kprintf("HAMMER2 DBG: %s\n", msg->aux_data);
2632 		}
2633 		break;
2634 	default:
2635 		/*
2636 		 * Unsupported message received.  We only need to
2637 		 * reply if it's a transaction in order to close our end.
2638 		 * Ignore any one-way messages or any further messages
2639 		 * associated with the transaction.
2640 		 *
2641 		 * NOTE: This case also includes DMSG_LNK_ERROR messages
2642 		 *	 which might be one-way, replying to those would
2643 		 *	 cause an infinite ping-pong.
2644 		 */
2645 		if (msg->any.head.cmd & DMSGF_CREATE)
2646 			kdmsg_msg_reply(msg, DMSG_ERR_NOSUPP);
2647 		break;
2648 	}
2649 	return(0);
2650 }
2651 
2652 /*
2653  * This function is called after KDMSG has automatically handled processing
2654  * of a LNK layer message (typically CONN, SPAN, or CIRC).
2655  *
2656  * We tag off the LNK_CONN to trigger our LNK_VOLCONF messages which
2657  * advertises all available hammer2 super-root volumes.
2658  */
2659 static void
2660 hammer2_autodmsg(kdmsg_msg_t *msg)
2661 {
2662 	hammer2_mount_t *hmp = msg->iocom->handle;
2663 	int copyid;
2664 
2665 	kprintf("RCAMSG %08x\n", msg->tcmd);
2666 
2667 	switch(msg->tcmd) {
2668 	case DMSG_LNK_CONN | DMSGF_CREATE | DMSGF_REPLY:
2669 	case DMSG_LNK_CONN | DMSGF_CREATE | DMSGF_DELETE | DMSGF_REPLY:
2670 		if (msg->any.head.cmd & DMSGF_CREATE) {
2671 			kprintf("HAMMER2: VOLDATA DUMP\n");
2672 
2673 			/*
2674 			 * Dump the configuration stored in the volume header.
2675 			 * This will typically be import/export access rights,
2676 			 * master encryption keys (encrypted), etc.
2677 			 */
2678 			hammer2_voldata_lock(hmp);
2679 			copyid = 0;
2680 			while (copyid < HAMMER2_COPYID_COUNT) {
2681 				if (hmp->voldata.copyinfo[copyid].copyid)
2682 					hammer2_volconf_update(hmp, copyid);
2683 				++copyid;
2684 			}
2685 			hammer2_voldata_unlock(hmp);
2686 
2687 			kprintf("HAMMER2: INITIATE SPANs\n");
2688 			hammer2_update_spans(hmp);
2689 		}
2690 		if ((msg->any.head.cmd & DMSGF_DELETE) &&
2691 		    msg->state && (msg->state->txcmd & DMSGF_DELETE) == 0) {
2692 			kprintf("HAMMER2: CONN WAS TERMINATED\n");
2693 		}
2694 		break;
2695 	default:
2696 		break;
2697 	}
2698 }
2699 
2700 /*
2701  * Update LNK_SPAN state
2702  */
2703 void
2704 hammer2_update_spans(hammer2_mount_t *hmp)
2705 {
2706 	const hammer2_inode_data_t *ipdata;
2707 	hammer2_cluster_t *cparent;
2708 	hammer2_cluster_t *cluster;
2709 	hammer2_pfsmount_t *spmp;
2710 	hammer2_key_t key_next;
2711 	kdmsg_msg_t *rmsg;
2712 	size_t name_len;
2713 	int ddflag;
2714 
2715 	/*
2716 	 * Lookup mount point under the media-localized super-root.
2717 	 *
2718 	 * cluster->pmp will incorrectly point to spmp and must be fixed
2719 	 * up later on.
2720 	 */
2721 	spmp = hmp->spmp;
2722 	cparent = hammer2_inode_lock_ex(spmp->iroot);
2723 	cluster = hammer2_cluster_lookup(cparent, &key_next,
2724 					 HAMMER2_KEY_MIN,
2725 					 HAMMER2_KEY_MAX,
2726 					 0, &ddflag);
2727 	while (cluster) {
2728 		if (hammer2_cluster_type(cluster) != HAMMER2_BREF_TYPE_INODE)
2729 			continue;
2730 		ipdata = &hammer2_cluster_data(cluster)->ipdata;
2731 		kprintf("UPDATE SPANS: %s\n", ipdata->filename);
2732 
2733 		rmsg = kdmsg_msg_alloc(&hmp->iocom, NULL,
2734 				       DMSG_LNK_SPAN | DMSGF_CREATE,
2735 				       hammer2_lnk_span_reply, NULL);
2736 		rmsg->any.lnk_span.pfs_clid = ipdata->pfs_clid;
2737 		rmsg->any.lnk_span.pfs_fsid = ipdata->pfs_fsid;
2738 		rmsg->any.lnk_span.pfs_type = ipdata->pfs_type;
2739 		rmsg->any.lnk_span.peer_type = DMSG_PEER_HAMMER2;
2740 		rmsg->any.lnk_span.proto_version = DMSG_SPAN_PROTO_1;
2741 		name_len = ipdata->name_len;
2742 		if (name_len >= sizeof(rmsg->any.lnk_span.fs_label))
2743 			name_len = sizeof(rmsg->any.lnk_span.fs_label) - 1;
2744 		bcopy(ipdata->filename, rmsg->any.lnk_span.fs_label, name_len);
2745 
2746 		kdmsg_msg_write(rmsg);
2747 
2748 		cluster = hammer2_cluster_next(cparent, cluster,
2749 					       &key_next,
2750 					       key_next,
2751 					       HAMMER2_KEY_MAX,
2752 					       0);
2753 	}
2754 	hammer2_inode_unlock_ex(spmp->iroot, cparent);
2755 }
2756 
2757 static
2758 int
2759 hammer2_lnk_span_reply(kdmsg_state_t *state, kdmsg_msg_t *msg)
2760 {
2761 	if ((state->txcmd & DMSGF_DELETE) == 0 &&
2762 	    (msg->any.head.cmd & DMSGF_DELETE)) {
2763 		kdmsg_msg_reply(msg, 0);
2764 	}
2765 	return 0;
2766 }
2767 
2768 /*
2769  * Volume configuration updates are passed onto the userland service
2770  * daemon via the open LNK_CONN transaction.
2771  */
2772 void
2773 hammer2_volconf_update(hammer2_mount_t *hmp, int index)
2774 {
2775 	kdmsg_msg_t *msg;
2776 
2777 	/* XXX interlock against connection state termination */
2778 	kprintf("volconf update %p\n", hmp->iocom.conn_state);
2779 	if (hmp->iocom.conn_state) {
2780 		kprintf("TRANSMIT VOLCONF VIA OPEN CONN TRANSACTION\n");
2781 		msg = kdmsg_msg_alloc_state(hmp->iocom.conn_state,
2782 					    DMSG_LNK_HAMMER2_VOLCONF,
2783 					    NULL, NULL);
2784 		H2_LNK_VOLCONF(msg)->copy = hmp->voldata.copyinfo[index];
2785 		H2_LNK_VOLCONF(msg)->mediaid = hmp->voldata.fsid;
2786 		H2_LNK_VOLCONF(msg)->index = index;
2787 		kdmsg_msg_write(msg);
2788 	}
2789 }
2790 
2791 /*
2792  * This handles hysteresis on regular file flushes.  Because the BIOs are
2793  * routed to a thread it is possible for an excessive number to build up
2794  * and cause long front-end stalls long before the runningbuffspace limit
2795  * is hit, so we implement hammer2_flush_pipe to control the
2796  * hysteresis.
2797  *
2798  * This is a particular problem when compression is used.
2799  */
2800 void
2801 hammer2_lwinprog_ref(hammer2_pfsmount_t *pmp)
2802 {
2803 	atomic_add_int(&pmp->count_lwinprog, 1);
2804 }
2805 
2806 void
2807 hammer2_lwinprog_drop(hammer2_pfsmount_t *pmp)
2808 {
2809 	int lwinprog;
2810 
2811 	lwinprog = atomic_fetchadd_int(&pmp->count_lwinprog, -1);
2812 	if ((lwinprog & HAMMER2_LWINPROG_WAITING) &&
2813 	    (lwinprog & HAMMER2_LWINPROG_MASK) <= hammer2_flush_pipe * 2 / 3) {
2814 		atomic_clear_int(&pmp->count_lwinprog,
2815 				 HAMMER2_LWINPROG_WAITING);
2816 		wakeup(&pmp->count_lwinprog);
2817 	}
2818 }
2819 
2820 void
2821 hammer2_lwinprog_wait(hammer2_pfsmount_t *pmp)
2822 {
2823 	int lwinprog;
2824 
2825 	for (;;) {
2826 		lwinprog = pmp->count_lwinprog;
2827 		cpu_ccfence();
2828 		if ((lwinprog & HAMMER2_LWINPROG_MASK) < hammer2_flush_pipe)
2829 			break;
2830 		tsleep_interlock(&pmp->count_lwinprog, 0);
2831 		atomic_set_int(&pmp->count_lwinprog, HAMMER2_LWINPROG_WAITING);
2832 		lwinprog = pmp->count_lwinprog;
2833 		if ((lwinprog & HAMMER2_LWINPROG_MASK) < hammer2_flush_pipe)
2834 			break;
2835 		tsleep(&pmp->count_lwinprog, PINTERLOCKED, "h2wpipe", hz);
2836 	}
2837 }
2838 
2839 /*
2840  * Manage excessive memory resource use for chain and related
2841  * structures.
2842  */
2843 void
2844 hammer2_pfs_memory_wait(hammer2_pfsmount_t *pmp)
2845 {
2846 	long waiting;
2847 	long count;
2848 	long limit;
2849 #if 0
2850 	static int zzticks;
2851 #endif
2852 
2853 	/*
2854 	 * Atomic check condition and wait.  Also do an early speedup of
2855 	 * the syncer to try to avoid hitting the wait.
2856 	 */
2857 	for (;;) {
2858 		waiting = pmp->inmem_dirty_chains;
2859 		cpu_ccfence();
2860 		count = waiting & HAMMER2_DIRTYCHAIN_MASK;
2861 
2862 		limit = pmp->mp->mnt_nvnodelistsize / 10;
2863 		if (limit < hammer2_limit_dirty_chains)
2864 			limit = hammer2_limit_dirty_chains;
2865 		if (limit < 1000)
2866 			limit = 1000;
2867 
2868 #if 0
2869 		if ((int)(ticks - zzticks) > hz) {
2870 			zzticks = ticks;
2871 			kprintf("count %ld %ld\n", count, limit);
2872 		}
2873 #endif
2874 
2875 		/*
2876 		 * Block if there are too many dirty chains present, wait
2877 		 * for the flush to clean some out.
2878 		 */
2879 		if (count > limit) {
2880 			tsleep_interlock(&pmp->inmem_dirty_chains, 0);
2881 			if (atomic_cmpset_long(&pmp->inmem_dirty_chains,
2882 					       waiting,
2883 				       waiting | HAMMER2_DIRTYCHAIN_WAITING)) {
2884 				speedup_syncer(pmp->mp);
2885 				tsleep(&pmp->inmem_dirty_chains, PINTERLOCKED,
2886 				       "chnmem", hz);
2887 			}
2888 			continue;	/* loop on success or fail */
2889 		}
2890 
2891 		/*
2892 		 * Try to start an early flush before we are forced to block.
2893 		 */
2894 		if (count > limit * 7 / 10)
2895 			speedup_syncer(pmp->mp);
2896 		break;
2897 	}
2898 }
2899 
2900 void
2901 hammer2_pfs_memory_inc(hammer2_pfsmount_t *pmp)
2902 {
2903 	if (pmp)
2904 		atomic_add_long(&pmp->inmem_dirty_chains, 1);
2905 }
2906 
2907 void
2908 hammer2_pfs_memory_wakeup(hammer2_pfsmount_t *pmp)
2909 {
2910 	long waiting;
2911 
2912 	if (pmp == NULL)
2913 		return;
2914 
2915 	for (;;) {
2916 		waiting = pmp->inmem_dirty_chains;
2917 		cpu_ccfence();
2918 		if (atomic_cmpset_long(&pmp->inmem_dirty_chains,
2919 				       waiting,
2920 				       (waiting - 1) &
2921 					~HAMMER2_DIRTYCHAIN_WAITING)) {
2922 			break;
2923 		}
2924 	}
2925 
2926 	if (waiting & HAMMER2_DIRTYCHAIN_WAITING)
2927 		wakeup(&pmp->inmem_dirty_chains);
2928 }
2929 
2930 /*
2931  * Debugging
2932  */
2933 void
2934 hammer2_dump_chain(hammer2_chain_t *chain, int tab, int *countp, char pfx)
2935 {
2936 	hammer2_chain_t *scan;
2937 	hammer2_chain_t *first_parent;
2938 
2939 	--*countp;
2940 	if (*countp == 0) {
2941 		kprintf("%*.*s...\n", tab, tab, "");
2942 		return;
2943 	}
2944 	if (*countp < 0)
2945 		return;
2946 	first_parent = chain->core ? TAILQ_FIRST(&chain->core->ownerq) : NULL;
2947 	kprintf("%*.*s%c-chain %p.%d %016jx/%d mir=%016jx\n",
2948 		tab, tab, "", pfx,
2949 		chain, chain->bref.type,
2950 		chain->bref.key, chain->bref.keybits,
2951 		chain->bref.mirror_tid);
2952 
2953 	kprintf("%*.*s      [%08x] (%s) mod=%08x del=%08x "
2954 		"lo=%08x hi=%08x refs=%d\n",
2955 		tab, tab, "",
2956 		chain->flags,
2957 		((chain->bref.type == HAMMER2_BREF_TYPE_INODE &&
2958 		chain->data) ?  (char *)chain->data->ipdata.filename : "?"),
2959 		chain->modify_xid,
2960 		chain->delete_xid,
2961 		chain->update_xlo,
2962 		chain->update_xhi,
2963 		chain->refs);
2964 
2965 	kprintf("%*.*s      core %p [%08x]",
2966 		tab, tab, "",
2967 		chain->core, (chain->core ? chain->core->flags : 0));
2968 
2969 	if (first_parent)
2970 		kprintf("\n%*.*s      fp=%p np=%p [fpflags %08x fprefs %d",
2971 			tab, tab, "",
2972 			first_parent,
2973 			(first_parent ? TAILQ_NEXT(first_parent, core_entry) :
2974 					NULL),
2975 			first_parent->flags,
2976 			first_parent->refs);
2977 	if (chain->core == NULL || RB_EMPTY(&chain->core->rbtree))
2978 		kprintf("\n");
2979 	else
2980 		kprintf(" {\n");
2981 	if (chain->core) {
2982 		RB_FOREACH(scan, hammer2_chain_tree, &chain->core->rbtree)
2983 			hammer2_dump_chain(scan, tab + 4, countp, 'a');
2984 		RB_FOREACH(scan, hammer2_chain_tree, &chain->core->dbtree)
2985 			hammer2_dump_chain(scan, tab + 4, countp, 'r');
2986 		TAILQ_FOREACH(scan, &chain->core->dbq, db_entry)
2987 			hammer2_dump_chain(scan, tab + 4, countp, 'd');
2988 	}
2989 	if (chain->core && !RB_EMPTY(&chain->core->rbtree)) {
2990 		if (chain->bref.type == HAMMER2_BREF_TYPE_INODE && chain->data)
2991 			kprintf("%*.*s}(%s)\n", tab, tab, "",
2992 				chain->data->ipdata.filename);
2993 		else
2994 			kprintf("%*.*s}\n", tab, tab, "");
2995 	}
2996 }
2997