xref: /netbsd-src/sys/kern/vfs_wapbl.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: vfs_wapbl.c,v 1.58 2013/09/15 15:59:37 martin Exp $	*/
2 
3 /*-
4  * Copyright (c) 2003, 2008, 2009 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Wasabi Systems, Inc.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * This implements file system independent write ahead filesystem logging.
34  */
35 
36 #define WAPBL_INTERNAL
37 
38 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: vfs_wapbl.c,v 1.58 2013/09/15 15:59:37 martin Exp $");
40 
41 #include <sys/param.h>
42 #include <sys/bitops.h>
43 
44 #ifdef _KERNEL
45 #include <sys/param.h>
46 #include <sys/namei.h>
47 #include <sys/proc.h>
48 #include <sys/sysctl.h>
49 #include <sys/uio.h>
50 #include <sys/vnode.h>
51 #include <sys/file.h>
52 #include <sys/module.h>
53 #include <sys/resourcevar.h>
54 #include <sys/conf.h>
55 #include <sys/mount.h>
56 #include <sys/kernel.h>
57 #include <sys/kauth.h>
58 #include <sys/mutex.h>
59 #include <sys/atomic.h>
60 #include <sys/wapbl.h>
61 #include <sys/wapbl_replay.h>
62 
63 #include <miscfs/specfs/specdev.h>
64 
65 #define	wapbl_alloc(s) kmem_alloc((s), KM_SLEEP)
66 #define	wapbl_free(a, s) kmem_free((a), (s))
67 #define	wapbl_calloc(n, s) kmem_zalloc((n)*(s), KM_SLEEP)
68 
69 static struct sysctllog *wapbl_sysctl;
70 static int wapbl_flush_disk_cache = 1;
71 static int wapbl_verbose_commit = 0;
72 
73 static inline size_t wapbl_space_free(size_t, off_t, off_t);
74 
75 #else /* !_KERNEL */
76 #include <assert.h>
77 #include <errno.h>
78 #include <stdio.h>
79 #include <stdbool.h>
80 #include <stdlib.h>
81 #include <string.h>
82 
83 #include <sys/time.h>
84 #include <sys/wapbl.h>
85 #include <sys/wapbl_replay.h>
86 
87 #define	KDASSERT(x) assert(x)
88 #define	KASSERT(x) assert(x)
89 #define	wapbl_alloc(s) malloc(s)
90 #define	wapbl_free(a, s) free(a)
91 #define	wapbl_calloc(n, s) calloc((n), (s))
92 
93 #endif /* !_KERNEL */
94 
95 /*
96  * INTERNAL DATA STRUCTURES
97  */
98 
99 /*
100  * This structure holds per-mount log information.
101  *
102  * Legend:	a = atomic access only
103  *		r = read-only after init
104  *		l = rwlock held
105  *		m = mutex held
106  *		lm = rwlock held writing or mutex held
107  *		u = unlocked access ok
108  *		b = bufcache_lock held
109  */
110 struct wapbl {
111 	struct vnode *wl_logvp;	/* r:	log here */
112 	struct vnode *wl_devvp;	/* r:	log on this device */
113 	struct mount *wl_mount;	/* r:	mountpoint wl is associated with */
114 	daddr_t wl_logpbn;	/* r:	Physical block number of start of log */
115 	int wl_log_dev_bshift;	/* r:	logarithm of device block size of log
116 					device */
117 	int wl_fs_dev_bshift;	/* r:	logarithm of device block size of
118 					filesystem device */
119 
120 	unsigned wl_lock_count;	/* m:	Count of transactions in progress */
121 
122 	size_t wl_circ_size; 	/* r:	Number of bytes in buffer of log */
123 	size_t wl_circ_off;	/* r:	Number of bytes reserved at start */
124 
125 	size_t wl_bufcount_max;	/* r:	Number of buffers reserved for log */
126 	size_t wl_bufbytes_max;	/* r:	Number of buf bytes reserved for log */
127 
128 	off_t wl_head;		/* l:	Byte offset of log head */
129 	off_t wl_tail;		/* l:	Byte offset of log tail */
130 	/*
131 	 * head == tail == 0 means log is empty
132 	 * head == tail != 0 means log is full
133 	 * see assertions in wapbl_advance() for other boundary conditions.
134 	 * only truncate moves the tail, except when flush sets it to
135 	 * wl_header_size only flush moves the head, except when truncate
136 	 * sets it to 0.
137 	 */
138 
139 	struct wapbl_wc_header *wl_wc_header;	/* l	*/
140 	void *wl_wc_scratch;	/* l:	scratch space (XXX: por que?!?) */
141 
142 	kmutex_t wl_mtx;	/* u:	short-term lock */
143 	krwlock_t wl_rwlock;	/* u:	File system transaction lock */
144 
145 	/*
146 	 * Must be held while accessing
147 	 * wl_count or wl_bufs or head or tail
148 	 */
149 
150 	/*
151 	 * Callback called from within the flush routine to flush any extra
152 	 * bits.  Note that flush may be skipped without calling this if
153 	 * there are no outstanding buffers in the transaction.
154 	 */
155 #if _KERNEL
156 	wapbl_flush_fn_t wl_flush;	/* r	*/
157 	wapbl_flush_fn_t wl_flush_abort;/* r	*/
158 #endif
159 
160 	size_t wl_bufbytes;	/* m:	Byte count of pages in wl_bufs */
161 	size_t wl_bufcount;	/* m:	Count of buffers in wl_bufs */
162 	size_t wl_bcount;	/* m:	Total bcount of wl_bufs */
163 
164 	LIST_HEAD(, buf) wl_bufs; /* m:	Buffers in current transaction */
165 
166 	kcondvar_t wl_reclaimable_cv;	/* m (obviously) */
167 	size_t wl_reclaimable_bytes; /* m:	Amount of space available for
168 						reclamation by truncate */
169 	int wl_error_count;	/* m:	# of wl_entries with errors */
170 	size_t wl_reserved_bytes; /* never truncate log smaller than this */
171 
172 #ifdef WAPBL_DEBUG_BUFBYTES
173 	size_t wl_unsynced_bufbytes; /* Byte count of unsynced buffers */
174 #endif
175 
176 	daddr_t *wl_deallocblks;/* lm:	address of block */
177 	int *wl_dealloclens;	/* lm:	size of block */
178 	int wl_dealloccnt;	/* lm:	total count */
179 	int wl_dealloclim;	/* l:	max count */
180 
181 	/* hashtable of inode numbers for allocated but unlinked inodes */
182 	/* synch ??? */
183 	LIST_HEAD(wapbl_ino_head, wapbl_ino) *wl_inohash;
184 	u_long wl_inohashmask;
185 	int wl_inohashcnt;
186 
187 	SIMPLEQ_HEAD(, wapbl_entry) wl_entries; /* On disk transaction
188 						   accounting */
189 
190 	u_char *wl_buffer;	/* l:   buffer for wapbl_buffered_write() */
191 	daddr_t wl_buffer_dblk;	/* l:   buffer disk block address */
192 	size_t wl_buffer_used;	/* l:   buffer current use */
193 };
194 
195 #ifdef WAPBL_DEBUG_PRINT
196 int wapbl_debug_print = WAPBL_DEBUG_PRINT;
197 #endif
198 
199 /****************************************************************/
200 #ifdef _KERNEL
201 
202 #ifdef WAPBL_DEBUG
203 struct wapbl *wapbl_debug_wl;
204 #endif
205 
206 static int wapbl_write_commit(struct wapbl *wl, off_t head, off_t tail);
207 static int wapbl_write_blocks(struct wapbl *wl, off_t *offp);
208 static int wapbl_write_revocations(struct wapbl *wl, off_t *offp);
209 static int wapbl_write_inodes(struct wapbl *wl, off_t *offp);
210 #endif /* _KERNEL */
211 
212 static int wapbl_replay_process(struct wapbl_replay *wr, off_t, off_t);
213 
214 static inline size_t wapbl_space_used(size_t avail, off_t head,
215 	off_t tail);
216 
217 #ifdef _KERNEL
218 
219 static struct pool wapbl_entry_pool;
220 
221 #define	WAPBL_INODETRK_SIZE 83
222 static int wapbl_ino_pool_refcount;
223 static struct pool wapbl_ino_pool;
224 struct wapbl_ino {
225 	LIST_ENTRY(wapbl_ino) wi_hash;
226 	ino_t wi_ino;
227 	mode_t wi_mode;
228 };
229 
230 static void wapbl_inodetrk_init(struct wapbl *wl, u_int size);
231 static void wapbl_inodetrk_free(struct wapbl *wl);
232 static struct wapbl_ino *wapbl_inodetrk_get(struct wapbl *wl, ino_t ino);
233 
234 static size_t wapbl_transaction_len(struct wapbl *wl);
235 static inline size_t wapbl_transaction_inodes_len(struct wapbl *wl);
236 
237 #if 0
238 int wapbl_replay_verify(struct wapbl_replay *, struct vnode *);
239 #endif
240 
241 static int wapbl_replay_isopen1(struct wapbl_replay *);
242 
243 /*
244  * This is useful for debugging.  If set, the log will
245  * only be truncated when necessary.
246  */
247 int wapbl_lazy_truncate = 0;
248 
249 struct wapbl_ops wapbl_ops = {
250 	.wo_wapbl_discard	= wapbl_discard,
251 	.wo_wapbl_replay_isopen	= wapbl_replay_isopen1,
252 	.wo_wapbl_replay_can_read = wapbl_replay_can_read,
253 	.wo_wapbl_replay_read	= wapbl_replay_read,
254 	.wo_wapbl_add_buf	= wapbl_add_buf,
255 	.wo_wapbl_remove_buf	= wapbl_remove_buf,
256 	.wo_wapbl_resize_buf	= wapbl_resize_buf,
257 	.wo_wapbl_begin		= wapbl_begin,
258 	.wo_wapbl_end		= wapbl_end,
259 	.wo_wapbl_junlock_assert= wapbl_junlock_assert,
260 
261 	/* XXX: the following is only used to say "this is a wapbl buf" */
262 	.wo_wapbl_biodone	= wapbl_biodone,
263 };
264 
265 static int
266 wapbl_sysctl_init(void)
267 {
268 	int rv;
269 	const struct sysctlnode *rnode, *cnode;
270 
271 	wapbl_sysctl = NULL;
272 
273 	rv = sysctl_createv(&wapbl_sysctl, 0, NULL, &rnode,
274 		       CTLFLAG_PERMANENT,
275 		       CTLTYPE_NODE, "vfs", NULL,
276 		       NULL, 0, NULL, 0,
277 		       CTL_VFS, CTL_EOL);
278 	if (rv)
279 		return rv;
280 
281 	rv = sysctl_createv(&wapbl_sysctl, 0, &rnode, &rnode,
282 		       CTLFLAG_PERMANENT,
283 		       CTLTYPE_NODE, "wapbl",
284 		       SYSCTL_DESCR("WAPBL journaling options"),
285 		       NULL, 0, NULL, 0,
286 		       CTL_CREATE, CTL_EOL);
287 	if (rv)
288 		return rv;
289 
290 	rv = sysctl_createv(&wapbl_sysctl, 0, &rnode, &cnode,
291 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
292 		       CTLTYPE_INT, "flush_disk_cache",
293 		       SYSCTL_DESCR("flush disk cache"),
294 		       NULL, 0, &wapbl_flush_disk_cache, 0,
295 		       CTL_CREATE, CTL_EOL);
296 	if (rv)
297 		return rv;
298 
299 	rv = sysctl_createv(&wapbl_sysctl, 0, &rnode, &cnode,
300 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
301 		       CTLTYPE_INT, "verbose_commit",
302 		       SYSCTL_DESCR("show time and size of wapbl log commits"),
303 		       NULL, 0, &wapbl_verbose_commit, 0,
304 		       CTL_CREATE, CTL_EOL);
305 	return rv;
306 }
307 
308 static void
309 wapbl_init(void)
310 {
311 
312 	pool_init(&wapbl_entry_pool, sizeof(struct wapbl_entry), 0, 0, 0,
313 	    "wapblentrypl", &pool_allocator_kmem, IPL_VM);
314 
315 	wapbl_sysctl_init();
316 }
317 
318 #ifdef notyet
319 static int
320 wapbl_fini(bool interface)
321 {
322 
323 	if (aio_sysctl != NULL)
324 		 sysctl_teardown(&aio_sysctl);
325 
326 	pool_destroy(&wapbl_entry_pool);
327 
328 	return 0;
329 }
330 #endif
331 
332 static int
333 wapbl_start_flush_inodes(struct wapbl *wl, struct wapbl_replay *wr)
334 {
335 	int error, i;
336 
337 	WAPBL_PRINTF(WAPBL_PRINT_REPLAY,
338 	    ("wapbl_start: reusing log with %d inodes\n", wr->wr_inodescnt));
339 
340 	/*
341 	 * Its only valid to reuse the replay log if its
342 	 * the same as the new log we just opened.
343 	 */
344 	KDASSERT(!wapbl_replay_isopen(wr));
345 	KASSERT(wl->wl_devvp->v_type == VBLK);
346 	KASSERT(wr->wr_devvp->v_type == VBLK);
347 	KASSERT(wl->wl_devvp->v_rdev == wr->wr_devvp->v_rdev);
348 	KASSERT(wl->wl_logpbn == wr->wr_logpbn);
349 	KASSERT(wl->wl_circ_size == wr->wr_circ_size);
350 	KASSERT(wl->wl_circ_off == wr->wr_circ_off);
351 	KASSERT(wl->wl_log_dev_bshift == wr->wr_log_dev_bshift);
352 	KASSERT(wl->wl_fs_dev_bshift == wr->wr_fs_dev_bshift);
353 
354 	wl->wl_wc_header->wc_generation = wr->wr_generation + 1;
355 
356 	for (i = 0; i < wr->wr_inodescnt; i++)
357 		wapbl_register_inode(wl, wr->wr_inodes[i].wr_inumber,
358 		    wr->wr_inodes[i].wr_imode);
359 
360 	/* Make sure new transaction won't overwrite old inodes list */
361 	KDASSERT(wapbl_transaction_len(wl) <=
362 	    wapbl_space_free(wl->wl_circ_size, wr->wr_inodeshead,
363 	    wr->wr_inodestail));
364 
365 	wl->wl_head = wl->wl_tail = wr->wr_inodeshead;
366 	wl->wl_reclaimable_bytes = wl->wl_reserved_bytes =
367 	    wapbl_transaction_len(wl);
368 
369 	error = wapbl_write_inodes(wl, &wl->wl_head);
370 	if (error)
371 		return error;
372 
373 	KASSERT(wl->wl_head != wl->wl_tail);
374 	KASSERT(wl->wl_head != 0);
375 
376 	return 0;
377 }
378 
379 int
380 wapbl_start(struct wapbl ** wlp, struct mount *mp, struct vnode *vp,
381 	daddr_t off, size_t count, size_t blksize, struct wapbl_replay *wr,
382 	wapbl_flush_fn_t flushfn, wapbl_flush_fn_t flushabortfn)
383 {
384 	struct wapbl *wl;
385 	struct vnode *devvp;
386 	daddr_t logpbn;
387 	int error;
388 	int log_dev_bshift = ilog2(blksize);
389 	int fs_dev_bshift = log_dev_bshift;
390 	int run;
391 
392 	WAPBL_PRINTF(WAPBL_PRINT_OPEN, ("wapbl_start: vp=%p off=%" PRId64
393 	    " count=%zu blksize=%zu\n", vp, off, count, blksize));
394 
395 	if (log_dev_bshift > fs_dev_bshift) {
396 		WAPBL_PRINTF(WAPBL_PRINT_OPEN,
397 			("wapbl: log device's block size cannot be larger "
398 			 "than filesystem's\n"));
399 		/*
400 		 * Not currently implemented, although it could be if
401 		 * needed someday.
402 		 */
403 		return ENOSYS;
404 	}
405 
406 	if (off < 0)
407 		return EINVAL;
408 
409 	if (blksize < DEV_BSIZE)
410 		return EINVAL;
411 	if (blksize % DEV_BSIZE)
412 		return EINVAL;
413 
414 	/* XXXTODO: verify that the full load is writable */
415 
416 	/*
417 	 * XXX check for minimum log size
418 	 * minimum is governed by minimum amount of space
419 	 * to complete a transaction. (probably truncate)
420 	 */
421 	/* XXX for now pick something minimal */
422 	if ((count * blksize) < MAXPHYS) {
423 		return ENOSPC;
424 	}
425 
426 	if ((error = VOP_BMAP(vp, off, &devvp, &logpbn, &run)) != 0) {
427 		return error;
428 	}
429 
430 	wl = wapbl_calloc(1, sizeof(*wl));
431 	rw_init(&wl->wl_rwlock);
432 	mutex_init(&wl->wl_mtx, MUTEX_DEFAULT, IPL_NONE);
433 	cv_init(&wl->wl_reclaimable_cv, "wapblrec");
434 	LIST_INIT(&wl->wl_bufs);
435 	SIMPLEQ_INIT(&wl->wl_entries);
436 
437 	wl->wl_logvp = vp;
438 	wl->wl_devvp = devvp;
439 	wl->wl_mount = mp;
440 	wl->wl_logpbn = logpbn;
441 	wl->wl_log_dev_bshift = log_dev_bshift;
442 	wl->wl_fs_dev_bshift = fs_dev_bshift;
443 
444 	wl->wl_flush = flushfn;
445 	wl->wl_flush_abort = flushabortfn;
446 
447 	/* Reserve two log device blocks for the commit headers */
448 	wl->wl_circ_off = 2<<wl->wl_log_dev_bshift;
449 	wl->wl_circ_size = ((count * blksize) - wl->wl_circ_off);
450 	/* truncate the log usage to a multiple of log_dev_bshift */
451 	wl->wl_circ_size >>= wl->wl_log_dev_bshift;
452 	wl->wl_circ_size <<= wl->wl_log_dev_bshift;
453 
454 	/*
455 	 * wl_bufbytes_max limits the size of the in memory transaction space.
456 	 * - Since buffers are allocated and accounted for in units of
457 	 *   PAGE_SIZE it is required to be a multiple of PAGE_SIZE
458 	 *   (i.e. 1<<PAGE_SHIFT)
459 	 * - Since the log device has to be written in units of
460 	 *   1<<wl_log_dev_bshift it is required to be a mulitple of
461 	 *   1<<wl_log_dev_bshift.
462 	 * - Since filesystem will provide data in units of 1<<wl_fs_dev_bshift,
463 	 *   it is convenient to be a multiple of 1<<wl_fs_dev_bshift.
464 	 * Therefore it must be multiple of the least common multiple of those
465 	 * three quantities.  Fortunately, all of those quantities are
466 	 * guaranteed to be a power of two, and the least common multiple of
467 	 * a set of numbers which are all powers of two is simply the maximum
468 	 * of those numbers.  Finally, the maximum logarithm of a power of two
469 	 * is the same as the log of the maximum power of two.  So we can do
470 	 * the following operations to size wl_bufbytes_max:
471 	 */
472 
473 	/* XXX fix actual number of pages reserved per filesystem. */
474 	wl->wl_bufbytes_max = MIN(wl->wl_circ_size, buf_memcalc() / 2);
475 
476 	/* Round wl_bufbytes_max to the largest power of two constraint */
477 	wl->wl_bufbytes_max >>= PAGE_SHIFT;
478 	wl->wl_bufbytes_max <<= PAGE_SHIFT;
479 	wl->wl_bufbytes_max >>= wl->wl_log_dev_bshift;
480 	wl->wl_bufbytes_max <<= wl->wl_log_dev_bshift;
481 	wl->wl_bufbytes_max >>= wl->wl_fs_dev_bshift;
482 	wl->wl_bufbytes_max <<= wl->wl_fs_dev_bshift;
483 
484 	/* XXX maybe use filesystem fragment size instead of 1024 */
485 	/* XXX fix actual number of buffers reserved per filesystem. */
486 	wl->wl_bufcount_max = (nbuf / 2) * 1024;
487 
488 	/* XXX tie this into resource estimation */
489 	wl->wl_dealloclim = wl->wl_bufbytes_max / mp->mnt_stat.f_bsize / 2;
490 
491 	wl->wl_deallocblks = wapbl_alloc(sizeof(*wl->wl_deallocblks) *
492 	    wl->wl_dealloclim);
493 	wl->wl_dealloclens = wapbl_alloc(sizeof(*wl->wl_dealloclens) *
494 	    wl->wl_dealloclim);
495 
496 	wl->wl_buffer = wapbl_alloc(MAXPHYS);
497 	wl->wl_buffer_used = 0;
498 
499 	wapbl_inodetrk_init(wl, WAPBL_INODETRK_SIZE);
500 
501 	/* Initialize the commit header */
502 	{
503 		struct wapbl_wc_header *wc;
504 		size_t len = 1 << wl->wl_log_dev_bshift;
505 		wc = wapbl_calloc(1, len);
506 		wc->wc_type = WAPBL_WC_HEADER;
507 		wc->wc_len = len;
508 		wc->wc_circ_off = wl->wl_circ_off;
509 		wc->wc_circ_size = wl->wl_circ_size;
510 		/* XXX wc->wc_fsid */
511 		wc->wc_log_dev_bshift = wl->wl_log_dev_bshift;
512 		wc->wc_fs_dev_bshift = wl->wl_fs_dev_bshift;
513 		wl->wl_wc_header = wc;
514 		wl->wl_wc_scratch = wapbl_alloc(len);
515 	}
516 
517 	/*
518 	 * if there was an existing set of unlinked but
519 	 * allocated inodes, preserve it in the new
520 	 * log.
521 	 */
522 	if (wr && wr->wr_inodescnt) {
523 		error = wapbl_start_flush_inodes(wl, wr);
524 		if (error)
525 			goto errout;
526 	}
527 
528 	error = wapbl_write_commit(wl, wl->wl_head, wl->wl_tail);
529 	if (error) {
530 		goto errout;
531 	}
532 
533 	*wlp = wl;
534 #if defined(WAPBL_DEBUG)
535 	wapbl_debug_wl = wl;
536 #endif
537 
538 	return 0;
539  errout:
540 	wapbl_discard(wl);
541 	wapbl_free(wl->wl_wc_scratch, wl->wl_wc_header->wc_len);
542 	wapbl_free(wl->wl_wc_header, wl->wl_wc_header->wc_len);
543 	wapbl_free(wl->wl_deallocblks,
544 	    sizeof(*wl->wl_deallocblks) * wl->wl_dealloclim);
545 	wapbl_free(wl->wl_dealloclens,
546 	    sizeof(*wl->wl_dealloclens) * wl->wl_dealloclim);
547 	wapbl_free(wl->wl_buffer, MAXPHYS);
548 	wapbl_inodetrk_free(wl);
549 	wapbl_free(wl, sizeof(*wl));
550 
551 	return error;
552 }
553 
554 /*
555  * Like wapbl_flush, only discards the transaction
556  * completely
557  */
558 
559 void
560 wapbl_discard(struct wapbl *wl)
561 {
562 	struct wapbl_entry *we;
563 	struct buf *bp;
564 	int i;
565 
566 	/*
567 	 * XXX we may consider using upgrade here
568 	 * if we want to call flush from inside a transaction
569 	 */
570 	rw_enter(&wl->wl_rwlock, RW_WRITER);
571 	wl->wl_flush(wl->wl_mount, wl->wl_deallocblks, wl->wl_dealloclens,
572 	    wl->wl_dealloccnt);
573 
574 #ifdef WAPBL_DEBUG_PRINT
575 	{
576 		pid_t pid = -1;
577 		lwpid_t lid = -1;
578 		if (curproc)
579 			pid = curproc->p_pid;
580 		if (curlwp)
581 			lid = curlwp->l_lid;
582 #ifdef WAPBL_DEBUG_BUFBYTES
583 		WAPBL_PRINTF(WAPBL_PRINT_DISCARD,
584 		    ("wapbl_discard: thread %d.%d discarding "
585 		    "transaction\n"
586 		    "\tbufcount=%zu bufbytes=%zu bcount=%zu "
587 		    "deallocs=%d inodes=%d\n"
588 		    "\terrcnt = %u, reclaimable=%zu reserved=%zu "
589 		    "unsynced=%zu\n",
590 		    pid, lid, wl->wl_bufcount, wl->wl_bufbytes,
591 		    wl->wl_bcount, wl->wl_dealloccnt,
592 		    wl->wl_inohashcnt, wl->wl_error_count,
593 		    wl->wl_reclaimable_bytes, wl->wl_reserved_bytes,
594 		    wl->wl_unsynced_bufbytes));
595 		SIMPLEQ_FOREACH(we, &wl->wl_entries, we_entries) {
596 			WAPBL_PRINTF(WAPBL_PRINT_DISCARD,
597 			    ("\tentry: bufcount = %zu, reclaimable = %zu, "
598 			     "error = %d, unsynced = %zu\n",
599 			     we->we_bufcount, we->we_reclaimable_bytes,
600 			     we->we_error, we->we_unsynced_bufbytes));
601 		}
602 #else /* !WAPBL_DEBUG_BUFBYTES */
603 		WAPBL_PRINTF(WAPBL_PRINT_DISCARD,
604 		    ("wapbl_discard: thread %d.%d discarding transaction\n"
605 		    "\tbufcount=%zu bufbytes=%zu bcount=%zu "
606 		    "deallocs=%d inodes=%d\n"
607 		    "\terrcnt = %u, reclaimable=%zu reserved=%zu\n",
608 		    pid, lid, wl->wl_bufcount, wl->wl_bufbytes,
609 		    wl->wl_bcount, wl->wl_dealloccnt,
610 		    wl->wl_inohashcnt, wl->wl_error_count,
611 		    wl->wl_reclaimable_bytes, wl->wl_reserved_bytes));
612 		SIMPLEQ_FOREACH(we, &wl->wl_entries, we_entries) {
613 			WAPBL_PRINTF(WAPBL_PRINT_DISCARD,
614 			    ("\tentry: bufcount = %zu, reclaimable = %zu, "
615 			     "error = %d\n",
616 			     we->we_bufcount, we->we_reclaimable_bytes,
617 			     we->we_error));
618 		}
619 #endif /* !WAPBL_DEBUG_BUFBYTES */
620 	}
621 #endif /* WAPBL_DEBUG_PRINT */
622 
623 	for (i = 0; i <= wl->wl_inohashmask; i++) {
624 		struct wapbl_ino_head *wih;
625 		struct wapbl_ino *wi;
626 
627 		wih = &wl->wl_inohash[i];
628 		while ((wi = LIST_FIRST(wih)) != NULL) {
629 			LIST_REMOVE(wi, wi_hash);
630 			pool_put(&wapbl_ino_pool, wi);
631 			KASSERT(wl->wl_inohashcnt > 0);
632 			wl->wl_inohashcnt--;
633 		}
634 	}
635 
636 	/*
637 	 * clean buffer list
638 	 */
639 	mutex_enter(&bufcache_lock);
640 	mutex_enter(&wl->wl_mtx);
641 	while ((bp = LIST_FIRST(&wl->wl_bufs)) != NULL) {
642 		if (bbusy(bp, 0, 0, &wl->wl_mtx) == 0) {
643 			/*
644 			 * The buffer will be unlocked and
645 			 * removed from the transaction in brelse
646 			 */
647 			mutex_exit(&wl->wl_mtx);
648 			brelsel(bp, 0);
649 			mutex_enter(&wl->wl_mtx);
650 		}
651 	}
652 	mutex_exit(&wl->wl_mtx);
653 	mutex_exit(&bufcache_lock);
654 
655 	/*
656 	 * Remove references to this wl from wl_entries, free any which
657 	 * no longer have buffers, others will be freed in wapbl_biodone
658 	 * when they no longer have any buffers.
659 	 */
660 	while ((we = SIMPLEQ_FIRST(&wl->wl_entries)) != NULL) {
661 		SIMPLEQ_REMOVE_HEAD(&wl->wl_entries, we_entries);
662 		/* XXX should we be accumulating wl_error_count
663 		 * and increasing reclaimable bytes ? */
664 		we->we_wapbl = NULL;
665 		if (we->we_bufcount == 0) {
666 #ifdef WAPBL_DEBUG_BUFBYTES
667 			KASSERT(we->we_unsynced_bufbytes == 0);
668 #endif
669 			pool_put(&wapbl_entry_pool, we);
670 		}
671 	}
672 
673 	/* Discard list of deallocs */
674 	wl->wl_dealloccnt = 0;
675 	/* XXX should we clear wl_reserved_bytes? */
676 
677 	KASSERT(wl->wl_bufbytes == 0);
678 	KASSERT(wl->wl_bcount == 0);
679 	KASSERT(wl->wl_bufcount == 0);
680 	KASSERT(LIST_EMPTY(&wl->wl_bufs));
681 	KASSERT(SIMPLEQ_EMPTY(&wl->wl_entries));
682 	KASSERT(wl->wl_inohashcnt == 0);
683 
684 	rw_exit(&wl->wl_rwlock);
685 }
686 
687 int
688 wapbl_stop(struct wapbl *wl, int force)
689 {
690 	int error;
691 
692 	WAPBL_PRINTF(WAPBL_PRINT_OPEN, ("wapbl_stop called\n"));
693 	error = wapbl_flush(wl, 1);
694 	if (error) {
695 		if (force)
696 			wapbl_discard(wl);
697 		else
698 			return error;
699 	}
700 
701 	/* Unlinked inodes persist after a flush */
702 	if (wl->wl_inohashcnt) {
703 		if (force) {
704 			wapbl_discard(wl);
705 		} else {
706 			return EBUSY;
707 		}
708 	}
709 
710 	KASSERT(wl->wl_bufbytes == 0);
711 	KASSERT(wl->wl_bcount == 0);
712 	KASSERT(wl->wl_bufcount == 0);
713 	KASSERT(LIST_EMPTY(&wl->wl_bufs));
714 	KASSERT(wl->wl_dealloccnt == 0);
715 	KASSERT(SIMPLEQ_EMPTY(&wl->wl_entries));
716 	KASSERT(wl->wl_inohashcnt == 0);
717 
718 	wapbl_free(wl->wl_wc_scratch, wl->wl_wc_header->wc_len);
719 	wapbl_free(wl->wl_wc_header, wl->wl_wc_header->wc_len);
720 	wapbl_free(wl->wl_deallocblks,
721 	    sizeof(*wl->wl_deallocblks) * wl->wl_dealloclim);
722 	wapbl_free(wl->wl_dealloclens,
723 	    sizeof(*wl->wl_dealloclens) * wl->wl_dealloclim);
724 	wapbl_free(wl->wl_buffer, MAXPHYS);
725 	wapbl_inodetrk_free(wl);
726 
727 	cv_destroy(&wl->wl_reclaimable_cv);
728 	mutex_destroy(&wl->wl_mtx);
729 	rw_destroy(&wl->wl_rwlock);
730 	wapbl_free(wl, sizeof(*wl));
731 
732 	return 0;
733 }
734 
735 static int
736 wapbl_doio(void *data, size_t len, struct vnode *devvp, daddr_t pbn, int flags)
737 {
738 	struct pstats *pstats = curlwp->l_proc->p_stats;
739 	struct buf *bp;
740 	int error;
741 
742 	KASSERT((flags & ~(B_WRITE | B_READ)) == 0);
743 	KASSERT(devvp->v_type == VBLK);
744 
745 	if ((flags & (B_WRITE | B_READ)) == B_WRITE) {
746 		mutex_enter(devvp->v_interlock);
747 		devvp->v_numoutput++;
748 		mutex_exit(devvp->v_interlock);
749 		pstats->p_ru.ru_oublock++;
750 	} else {
751 		pstats->p_ru.ru_inblock++;
752 	}
753 
754 	bp = getiobuf(devvp, true);
755 	bp->b_flags = flags;
756 	bp->b_cflags = BC_BUSY; /* silly & dubious */
757 	bp->b_dev = devvp->v_rdev;
758 	bp->b_data = data;
759 	bp->b_bufsize = bp->b_resid = bp->b_bcount = len;
760 	bp->b_blkno = pbn;
761 	BIO_SETPRIO(bp, BPRIO_TIMECRITICAL);
762 
763 	WAPBL_PRINTF(WAPBL_PRINT_IO,
764 	    ("wapbl_doio: %s %d bytes at block %"PRId64" on dev 0x%"PRIx64"\n",
765 	    BUF_ISWRITE(bp) ? "write" : "read", bp->b_bcount,
766 	    bp->b_blkno, bp->b_dev));
767 
768 	VOP_STRATEGY(devvp, bp);
769 
770 	error = biowait(bp);
771 	putiobuf(bp);
772 
773 	if (error) {
774 		WAPBL_PRINTF(WAPBL_PRINT_ERROR,
775 		    ("wapbl_doio: %s %zu bytes at block %" PRId64
776 		    " on dev 0x%"PRIx64" failed with error %d\n",
777 		    (((flags & (B_WRITE | B_READ)) == B_WRITE) ?
778 		     "write" : "read"),
779 		    len, pbn, devvp->v_rdev, error));
780 	}
781 
782 	return error;
783 }
784 
785 int
786 wapbl_write(void *data, size_t len, struct vnode *devvp, daddr_t pbn)
787 {
788 
789 	return wapbl_doio(data, len, devvp, pbn, B_WRITE);
790 }
791 
792 int
793 wapbl_read(void *data, size_t len, struct vnode *devvp, daddr_t pbn)
794 {
795 
796 	return wapbl_doio(data, len, devvp, pbn, B_READ);
797 }
798 
799 /*
800  * Flush buffered data if any.
801  */
802 static int
803 wapbl_buffered_flush(struct wapbl *wl)
804 {
805 	int error;
806 
807 	if (wl->wl_buffer_used == 0)
808 		return 0;
809 
810 	error = wapbl_doio(wl->wl_buffer, wl->wl_buffer_used,
811 	    wl->wl_devvp, wl->wl_buffer_dblk, B_WRITE);
812 	wl->wl_buffer_used = 0;
813 
814 	return error;
815 }
816 
817 /*
818  * Write data to the log.
819  * Try to coalesce writes and emit MAXPHYS aligned blocks.
820  */
821 static int
822 wapbl_buffered_write(void *data, size_t len, struct wapbl *wl, daddr_t pbn)
823 {
824 	int error;
825 	size_t resid;
826 
827 	/*
828 	 * If not adjacent to buffered data flush first.  Disk block
829 	 * address is always valid for non-empty buffer.
830 	 */
831 	if (wl->wl_buffer_used > 0 &&
832 	    pbn != wl->wl_buffer_dblk + btodb(wl->wl_buffer_used)) {
833 		error = wapbl_buffered_flush(wl);
834 		if (error)
835 			return error;
836 	}
837 	/*
838 	 * If this write goes to an empty buffer we have to
839 	 * save the disk block address first.
840 	 */
841 	if (wl->wl_buffer_used == 0)
842 		wl->wl_buffer_dblk = pbn;
843 	/*
844 	 * Remaining space so this buffer ends on a MAXPHYS boundary.
845 	 *
846 	 * Cannot become less or equal zero as the buffer would have been
847 	 * flushed on the last call then.
848 	 */
849 	resid = MAXPHYS - dbtob(wl->wl_buffer_dblk % btodb(MAXPHYS)) -
850 	    wl->wl_buffer_used;
851 	KASSERT(resid > 0);
852 	KASSERT(dbtob(btodb(resid)) == resid);
853 	if (len >= resid) {
854 		memcpy(wl->wl_buffer + wl->wl_buffer_used, data, resid);
855 		wl->wl_buffer_used += resid;
856 		error = wapbl_doio(wl->wl_buffer, wl->wl_buffer_used,
857 		    wl->wl_devvp, wl->wl_buffer_dblk, B_WRITE);
858 		data = (uint8_t *)data + resid;
859 		len -= resid;
860 		wl->wl_buffer_dblk = pbn + btodb(resid);
861 		wl->wl_buffer_used = 0;
862 		if (error)
863 			return error;
864 	}
865 	KASSERT(len < MAXPHYS);
866 	if (len > 0) {
867 		memcpy(wl->wl_buffer + wl->wl_buffer_used, data, len);
868 		wl->wl_buffer_used += len;
869 	}
870 
871 	return 0;
872 }
873 
874 /*
875  * Off is byte offset returns new offset for next write
876  * handles log wraparound
877  */
878 static int
879 wapbl_circ_write(struct wapbl *wl, void *data, size_t len, off_t *offp)
880 {
881 	size_t slen;
882 	off_t off = *offp;
883 	int error;
884 	daddr_t pbn;
885 
886 	KDASSERT(((len >> wl->wl_log_dev_bshift) <<
887 	    wl->wl_log_dev_bshift) == len);
888 
889 	if (off < wl->wl_circ_off)
890 		off = wl->wl_circ_off;
891 	slen = wl->wl_circ_off + wl->wl_circ_size - off;
892 	if (slen < len) {
893 		pbn = wl->wl_logpbn + (off >> wl->wl_log_dev_bshift);
894 #ifdef _KERNEL
895 		pbn = btodb(pbn << wl->wl_log_dev_bshift);
896 #endif
897 		error = wapbl_buffered_write(data, slen, wl, pbn);
898 		if (error)
899 			return error;
900 		data = (uint8_t *)data + slen;
901 		len -= slen;
902 		off = wl->wl_circ_off;
903 	}
904 	pbn = wl->wl_logpbn + (off >> wl->wl_log_dev_bshift);
905 #ifdef _KERNEL
906 	pbn = btodb(pbn << wl->wl_log_dev_bshift);
907 #endif
908 	error = wapbl_buffered_write(data, len, wl, pbn);
909 	if (error)
910 		return error;
911 	off += len;
912 	if (off >= wl->wl_circ_off + wl->wl_circ_size)
913 		off = wl->wl_circ_off;
914 	*offp = off;
915 	return 0;
916 }
917 
918 /****************************************************************/
919 
920 int
921 wapbl_begin(struct wapbl *wl, const char *file, int line)
922 {
923 	int doflush;
924 	unsigned lockcount;
925 
926 	KDASSERT(wl);
927 
928 	/*
929 	 * XXX this needs to be made much more sophisticated.
930 	 * perhaps each wapbl_begin could reserve a specified
931 	 * number of buffers and bytes.
932 	 */
933 	mutex_enter(&wl->wl_mtx);
934 	lockcount = wl->wl_lock_count;
935 	doflush = ((wl->wl_bufbytes + (lockcount * MAXPHYS)) >
936 		   wl->wl_bufbytes_max / 2) ||
937 		  ((wl->wl_bufcount + (lockcount * 10)) >
938 		   wl->wl_bufcount_max / 2) ||
939 		  (wapbl_transaction_len(wl) > wl->wl_circ_size / 2) ||
940 		  (wl->wl_dealloccnt >= (wl->wl_dealloclim / 2));
941 	mutex_exit(&wl->wl_mtx);
942 
943 	if (doflush) {
944 		WAPBL_PRINTF(WAPBL_PRINT_FLUSH,
945 		    ("force flush lockcnt=%d bufbytes=%zu "
946 		    "(max=%zu) bufcount=%zu (max=%zu) "
947 		    "dealloccnt %d (lim=%d)\n",
948 		    lockcount, wl->wl_bufbytes,
949 		    wl->wl_bufbytes_max, wl->wl_bufcount,
950 		    wl->wl_bufcount_max,
951 		    wl->wl_dealloccnt, wl->wl_dealloclim));
952 	}
953 
954 	if (doflush) {
955 		int error = wapbl_flush(wl, 0);
956 		if (error)
957 			return error;
958 	}
959 
960 	rw_enter(&wl->wl_rwlock, RW_READER);
961 	mutex_enter(&wl->wl_mtx);
962 	wl->wl_lock_count++;
963 	mutex_exit(&wl->wl_mtx);
964 
965 #if defined(WAPBL_DEBUG_PRINT)
966 	WAPBL_PRINTF(WAPBL_PRINT_TRANSACTION,
967 	    ("wapbl_begin thread %d.%d with bufcount=%zu "
968 	    "bufbytes=%zu bcount=%zu at %s:%d\n",
969 	    curproc->p_pid, curlwp->l_lid, wl->wl_bufcount,
970 	    wl->wl_bufbytes, wl->wl_bcount, file, line));
971 #endif
972 
973 	return 0;
974 }
975 
976 void
977 wapbl_end(struct wapbl *wl)
978 {
979 
980 #if defined(WAPBL_DEBUG_PRINT)
981 	WAPBL_PRINTF(WAPBL_PRINT_TRANSACTION,
982 	     ("wapbl_end thread %d.%d with bufcount=%zu "
983 	      "bufbytes=%zu bcount=%zu\n",
984 	      curproc->p_pid, curlwp->l_lid, wl->wl_bufcount,
985 	      wl->wl_bufbytes, wl->wl_bcount));
986 #endif
987 
988 #ifdef DIAGNOSTIC
989 	size_t flushsize = wapbl_transaction_len(wl);
990 	if (flushsize > (wl->wl_circ_size - wl->wl_reserved_bytes)) {
991 		/*
992 		 * XXX this could be handled more gracefully, perhaps place
993 		 * only a partial transaction in the log and allow the
994 		 * remaining to flush without the protection of the journal.
995 		 */
996 		panic("wapbl_end: current transaction too big to flush\n");
997 	}
998 #endif
999 
1000 	mutex_enter(&wl->wl_mtx);
1001 	KASSERT(wl->wl_lock_count > 0);
1002 	wl->wl_lock_count--;
1003 	mutex_exit(&wl->wl_mtx);
1004 
1005 	rw_exit(&wl->wl_rwlock);
1006 }
1007 
1008 void
1009 wapbl_add_buf(struct wapbl *wl, struct buf * bp)
1010 {
1011 
1012 	KASSERT(bp->b_cflags & BC_BUSY);
1013 	KASSERT(bp->b_vp);
1014 
1015 	wapbl_jlock_assert(wl);
1016 
1017 #if 0
1018 	/*
1019 	 * XXX this might be an issue for swapfiles.
1020 	 * see uvm_swap.c:1702
1021 	 *
1022 	 * XXX2 why require it then?  leap of semantics?
1023 	 */
1024 	KASSERT((bp->b_cflags & BC_NOCACHE) == 0);
1025 #endif
1026 
1027 	mutex_enter(&wl->wl_mtx);
1028 	if (bp->b_flags & B_LOCKED) {
1029 		LIST_REMOVE(bp, b_wapbllist);
1030 		WAPBL_PRINTF(WAPBL_PRINT_BUFFER2,
1031 		   ("wapbl_add_buf thread %d.%d re-adding buf %p "
1032 		    "with %d bytes %d bcount\n",
1033 		    curproc->p_pid, curlwp->l_lid, bp, bp->b_bufsize,
1034 		    bp->b_bcount));
1035 	} else {
1036 		/* unlocked by dirty buffers shouldn't exist */
1037 		KASSERT(!(bp->b_oflags & BO_DELWRI));
1038 		wl->wl_bufbytes += bp->b_bufsize;
1039 		wl->wl_bcount += bp->b_bcount;
1040 		wl->wl_bufcount++;
1041 		WAPBL_PRINTF(WAPBL_PRINT_BUFFER,
1042 		   ("wapbl_add_buf thread %d.%d adding buf %p "
1043 		    "with %d bytes %d bcount\n",
1044 		    curproc->p_pid, curlwp->l_lid, bp, bp->b_bufsize,
1045 		    bp->b_bcount));
1046 	}
1047 	LIST_INSERT_HEAD(&wl->wl_bufs, bp, b_wapbllist);
1048 	mutex_exit(&wl->wl_mtx);
1049 
1050 	bp->b_flags |= B_LOCKED;
1051 }
1052 
1053 static void
1054 wapbl_remove_buf_locked(struct wapbl * wl, struct buf *bp)
1055 {
1056 
1057 	KASSERT(mutex_owned(&wl->wl_mtx));
1058 	KASSERT(bp->b_cflags & BC_BUSY);
1059 	wapbl_jlock_assert(wl);
1060 
1061 #if 0
1062 	/*
1063 	 * XXX this might be an issue for swapfiles.
1064 	 * see uvm_swap.c:1725
1065 	 *
1066 	 * XXXdeux: see above
1067 	 */
1068 	KASSERT((bp->b_flags & BC_NOCACHE) == 0);
1069 #endif
1070 	KASSERT(bp->b_flags & B_LOCKED);
1071 
1072 	WAPBL_PRINTF(WAPBL_PRINT_BUFFER,
1073 	   ("wapbl_remove_buf thread %d.%d removing buf %p with "
1074 	    "%d bytes %d bcount\n",
1075 	    curproc->p_pid, curlwp->l_lid, bp, bp->b_bufsize, bp->b_bcount));
1076 
1077 	KASSERT(wl->wl_bufbytes >= bp->b_bufsize);
1078 	wl->wl_bufbytes -= bp->b_bufsize;
1079 	KASSERT(wl->wl_bcount >= bp->b_bcount);
1080 	wl->wl_bcount -= bp->b_bcount;
1081 	KASSERT(wl->wl_bufcount > 0);
1082 	wl->wl_bufcount--;
1083 	KASSERT((wl->wl_bufcount == 0) == (wl->wl_bufbytes == 0));
1084 	KASSERT((wl->wl_bufcount == 0) == (wl->wl_bcount == 0));
1085 	LIST_REMOVE(bp, b_wapbllist);
1086 
1087 	bp->b_flags &= ~B_LOCKED;
1088 }
1089 
1090 /* called from brelsel() in vfs_bio among other places */
1091 void
1092 wapbl_remove_buf(struct wapbl * wl, struct buf *bp)
1093 {
1094 
1095 	mutex_enter(&wl->wl_mtx);
1096 	wapbl_remove_buf_locked(wl, bp);
1097 	mutex_exit(&wl->wl_mtx);
1098 }
1099 
1100 void
1101 wapbl_resize_buf(struct wapbl *wl, struct buf *bp, long oldsz, long oldcnt)
1102 {
1103 
1104 	KASSERT(bp->b_cflags & BC_BUSY);
1105 
1106 	/*
1107 	 * XXX: why does this depend on B_LOCKED?  otherwise the buf
1108 	 * is not for a transaction?  if so, why is this called in the
1109 	 * first place?
1110 	 */
1111 	if (bp->b_flags & B_LOCKED) {
1112 		mutex_enter(&wl->wl_mtx);
1113 		wl->wl_bufbytes += bp->b_bufsize - oldsz;
1114 		wl->wl_bcount += bp->b_bcount - oldcnt;
1115 		mutex_exit(&wl->wl_mtx);
1116 	}
1117 }
1118 
1119 #endif /* _KERNEL */
1120 
1121 /****************************************************************/
1122 /* Some utility inlines */
1123 
1124 static inline size_t
1125 wapbl_space_used(size_t avail, off_t head, off_t tail)
1126 {
1127 
1128 	if (tail == 0) {
1129 		KASSERT(head == 0);
1130 		return 0;
1131 	}
1132 	return ((head + (avail - 1) - tail) % avail) + 1;
1133 }
1134 
1135 #ifdef _KERNEL
1136 /* This is used to advance the pointer at old to new value at old+delta */
1137 static inline off_t
1138 wapbl_advance(size_t size, size_t off, off_t old, size_t delta)
1139 {
1140 	off_t new;
1141 
1142 	/* Define acceptable ranges for inputs. */
1143 	KASSERT(delta <= (size_t)size);
1144 	KASSERT((old == 0) || ((size_t)old >= off));
1145 	KASSERT(old < (off_t)(size + off));
1146 
1147 	if ((old == 0) && (delta != 0))
1148 		new = off + delta;
1149 	else if ((old + delta) < (size + off))
1150 		new = old + delta;
1151 	else
1152 		new = (old + delta) - size;
1153 
1154 	/* Note some interesting axioms */
1155 	KASSERT((delta != 0) || (new == old));
1156 	KASSERT((delta == 0) || (new != 0));
1157 	KASSERT((delta != (size)) || (new == old));
1158 
1159 	/* Define acceptable ranges for output. */
1160 	KASSERT((new == 0) || ((size_t)new >= off));
1161 	KASSERT((size_t)new < (size + off));
1162 	return new;
1163 }
1164 
1165 static inline size_t
1166 wapbl_space_free(size_t avail, off_t head, off_t tail)
1167 {
1168 
1169 	return avail - wapbl_space_used(avail, head, tail);
1170 }
1171 
1172 static inline void
1173 wapbl_advance_head(size_t size, size_t off, size_t delta, off_t *headp,
1174 		   off_t *tailp)
1175 {
1176 	off_t head = *headp;
1177 	off_t tail = *tailp;
1178 
1179 	KASSERT(delta <= wapbl_space_free(size, head, tail));
1180 	head = wapbl_advance(size, off, head, delta);
1181 	if ((tail == 0) && (head != 0))
1182 		tail = off;
1183 	*headp = head;
1184 	*tailp = tail;
1185 }
1186 
1187 static inline void
1188 wapbl_advance_tail(size_t size, size_t off, size_t delta, off_t *headp,
1189 		   off_t *tailp)
1190 {
1191 	off_t head = *headp;
1192 	off_t tail = *tailp;
1193 
1194 	KASSERT(delta <= wapbl_space_used(size, head, tail));
1195 	tail = wapbl_advance(size, off, tail, delta);
1196 	if (head == tail) {
1197 		head = tail = 0;
1198 	}
1199 	*headp = head;
1200 	*tailp = tail;
1201 }
1202 
1203 
1204 /****************************************************************/
1205 
1206 /*
1207  * Remove transactions whose buffers are completely flushed to disk.
1208  * Will block until at least minfree space is available.
1209  * only intended to be called from inside wapbl_flush and therefore
1210  * does not protect against commit races with itself or with flush.
1211  */
1212 static int
1213 wapbl_truncate(struct wapbl *wl, size_t minfree, int waitonly)
1214 {
1215 	size_t delta;
1216 	size_t avail;
1217 	off_t head;
1218 	off_t tail;
1219 	int error = 0;
1220 
1221 	KASSERT(minfree <= (wl->wl_circ_size - wl->wl_reserved_bytes));
1222 	KASSERT(rw_write_held(&wl->wl_rwlock));
1223 
1224 	mutex_enter(&wl->wl_mtx);
1225 
1226 	/*
1227 	 * First check to see if we have to do a commit
1228 	 * at all.
1229 	 */
1230 	avail = wapbl_space_free(wl->wl_circ_size, wl->wl_head, wl->wl_tail);
1231 	if (minfree < avail) {
1232 		mutex_exit(&wl->wl_mtx);
1233 		return 0;
1234 	}
1235 	minfree -= avail;
1236 	while ((wl->wl_error_count == 0) &&
1237 	    (wl->wl_reclaimable_bytes < minfree)) {
1238         	WAPBL_PRINTF(WAPBL_PRINT_TRUNCATE,
1239                    ("wapbl_truncate: sleeping on %p wl=%p bytes=%zd "
1240 		    "minfree=%zd\n",
1241                     &wl->wl_reclaimable_bytes, wl, wl->wl_reclaimable_bytes,
1242 		    minfree));
1243 
1244 		cv_wait(&wl->wl_reclaimable_cv, &wl->wl_mtx);
1245 	}
1246 	if (wl->wl_reclaimable_bytes < minfree) {
1247 		KASSERT(wl->wl_error_count);
1248 		/* XXX maybe get actual error from buffer instead someday? */
1249 		error = EIO;
1250 	}
1251 	head = wl->wl_head;
1252 	tail = wl->wl_tail;
1253 	delta = wl->wl_reclaimable_bytes;
1254 
1255 	/* If all of of the entries are flushed, then be sure to keep
1256 	 * the reserved bytes reserved.  Watch out for discarded transactions,
1257 	 * which could leave more bytes reserved than are reclaimable.
1258 	 */
1259 	if (SIMPLEQ_EMPTY(&wl->wl_entries) &&
1260 	    (delta >= wl->wl_reserved_bytes)) {
1261 		delta -= wl->wl_reserved_bytes;
1262 	}
1263 	wapbl_advance_tail(wl->wl_circ_size, wl->wl_circ_off, delta, &head,
1264 			   &tail);
1265 	KDASSERT(wl->wl_reserved_bytes <=
1266 		wapbl_space_used(wl->wl_circ_size, head, tail));
1267 	mutex_exit(&wl->wl_mtx);
1268 
1269 	if (error)
1270 		return error;
1271 
1272 	if (waitonly)
1273 		return 0;
1274 
1275 	/*
1276 	 * This is where head, tail and delta are unprotected
1277 	 * from races against itself or flush.  This is ok since
1278 	 * we only call this routine from inside flush itself.
1279 	 *
1280 	 * XXX: how can it race against itself when accessed only
1281 	 * from behind the write-locked rwlock?
1282 	 */
1283 	error = wapbl_write_commit(wl, head, tail);
1284 	if (error)
1285 		return error;
1286 
1287 	wl->wl_head = head;
1288 	wl->wl_tail = tail;
1289 
1290 	mutex_enter(&wl->wl_mtx);
1291 	KASSERT(wl->wl_reclaimable_bytes >= delta);
1292 	wl->wl_reclaimable_bytes -= delta;
1293 	mutex_exit(&wl->wl_mtx);
1294 	WAPBL_PRINTF(WAPBL_PRINT_TRUNCATE,
1295 	    ("wapbl_truncate thread %d.%d truncating %zu bytes\n",
1296 	    curproc->p_pid, curlwp->l_lid, delta));
1297 
1298 	return 0;
1299 }
1300 
1301 /****************************************************************/
1302 
1303 void
1304 wapbl_biodone(struct buf *bp)
1305 {
1306 	struct wapbl_entry *we = bp->b_private;
1307 	struct wapbl *wl = we->we_wapbl;
1308 #ifdef WAPBL_DEBUG_BUFBYTES
1309 	const int bufsize = bp->b_bufsize;
1310 #endif
1311 
1312 	/*
1313 	 * Handle possible flushing of buffers after log has been
1314 	 * decomissioned.
1315 	 */
1316 	if (!wl) {
1317 		KASSERT(we->we_bufcount > 0);
1318 		we->we_bufcount--;
1319 #ifdef WAPBL_DEBUG_BUFBYTES
1320 		KASSERT(we->we_unsynced_bufbytes >= bufsize);
1321 		we->we_unsynced_bufbytes -= bufsize;
1322 #endif
1323 
1324 		if (we->we_bufcount == 0) {
1325 #ifdef WAPBL_DEBUG_BUFBYTES
1326 			KASSERT(we->we_unsynced_bufbytes == 0);
1327 #endif
1328 			pool_put(&wapbl_entry_pool, we);
1329 		}
1330 
1331 		brelse(bp, 0);
1332 		return;
1333 	}
1334 
1335 #ifdef ohbother
1336 	KDASSERT(bp->b_oflags & BO_DONE);
1337 	KDASSERT(!(bp->b_oflags & BO_DELWRI));
1338 	KDASSERT(bp->b_flags & B_ASYNC);
1339 	KDASSERT(bp->b_cflags & BC_BUSY);
1340 	KDASSERT(!(bp->b_flags & B_LOCKED));
1341 	KDASSERT(!(bp->b_flags & B_READ));
1342 	KDASSERT(!(bp->b_cflags & BC_INVAL));
1343 	KDASSERT(!(bp->b_cflags & BC_NOCACHE));
1344 #endif
1345 
1346 	if (bp->b_error) {
1347 #ifdef notyet /* Can't currently handle possible dirty buffer reuse */
1348 		/*
1349 		 * XXXpooka: interfaces not fully updated
1350 		 * Note: this was not enabled in the original patch
1351 		 * against netbsd4 either.  I don't know if comment
1352 		 * above is true or not.
1353 		 */
1354 
1355 		/*
1356 		 * If an error occurs, report the error and leave the
1357 		 * buffer as a delayed write on the LRU queue.
1358 		 * restarting the write would likely result in
1359 		 * an error spinloop, so let it be done harmlessly
1360 		 * by the syncer.
1361 		 */
1362 		bp->b_flags &= ~(B_DONE);
1363 		simple_unlock(&bp->b_interlock);
1364 
1365 		if (we->we_error == 0) {
1366 			mutex_enter(&wl->wl_mtx);
1367 			wl->wl_error_count++;
1368 			mutex_exit(&wl->wl_mtx);
1369 			cv_broadcast(&wl->wl_reclaimable_cv);
1370 		}
1371 		we->we_error = bp->b_error;
1372 		bp->b_error = 0;
1373 		brelse(bp);
1374 		return;
1375 #else
1376 		/* For now, just mark the log permanently errored out */
1377 
1378 		mutex_enter(&wl->wl_mtx);
1379 		if (wl->wl_error_count == 0) {
1380 			wl->wl_error_count++;
1381 			cv_broadcast(&wl->wl_reclaimable_cv);
1382 		}
1383 		mutex_exit(&wl->wl_mtx);
1384 #endif
1385 	}
1386 
1387 	/*
1388 	 * Release the buffer here. wapbl_flush() may wait for the
1389 	 * log to become empty and we better unbusy the buffer before
1390 	 * wapbl_flush() returns.
1391 	 */
1392 	brelse(bp, 0);
1393 
1394 	mutex_enter(&wl->wl_mtx);
1395 
1396 	KASSERT(we->we_bufcount > 0);
1397 	we->we_bufcount--;
1398 #ifdef WAPBL_DEBUG_BUFBYTES
1399 	KASSERT(we->we_unsynced_bufbytes >= bufsize);
1400 	we->we_unsynced_bufbytes -= bufsize;
1401 	KASSERT(wl->wl_unsynced_bufbytes >= bufsize);
1402 	wl->wl_unsynced_bufbytes -= bufsize;
1403 #endif
1404 
1405 	/*
1406 	 * If the current transaction can be reclaimed, start
1407 	 * at the beginning and reclaim any consecutive reclaimable
1408 	 * transactions.  If we successfully reclaim anything,
1409 	 * then wakeup anyone waiting for the reclaim.
1410 	 */
1411 	if (we->we_bufcount == 0) {
1412 		size_t delta = 0;
1413 		int errcnt = 0;
1414 #ifdef WAPBL_DEBUG_BUFBYTES
1415 		KDASSERT(we->we_unsynced_bufbytes == 0);
1416 #endif
1417 		/*
1418 		 * clear any posted error, since the buffer it came from
1419 		 * has successfully flushed by now
1420 		 */
1421 		while ((we = SIMPLEQ_FIRST(&wl->wl_entries)) &&
1422 		       (we->we_bufcount == 0)) {
1423 			delta += we->we_reclaimable_bytes;
1424 			if (we->we_error)
1425 				errcnt++;
1426 			SIMPLEQ_REMOVE_HEAD(&wl->wl_entries, we_entries);
1427 			pool_put(&wapbl_entry_pool, we);
1428 		}
1429 
1430 		if (delta) {
1431 			wl->wl_reclaimable_bytes += delta;
1432 			KASSERT(wl->wl_error_count >= errcnt);
1433 			wl->wl_error_count -= errcnt;
1434 			cv_broadcast(&wl->wl_reclaimable_cv);
1435 		}
1436 	}
1437 
1438 	mutex_exit(&wl->wl_mtx);
1439 }
1440 
1441 /*
1442  * Write transactions to disk + start I/O for contents
1443  */
1444 int
1445 wapbl_flush(struct wapbl *wl, int waitfor)
1446 {
1447 	struct buf *bp;
1448 	struct wapbl_entry *we;
1449 	off_t off;
1450 	off_t head;
1451 	off_t tail;
1452 	size_t delta = 0;
1453 	size_t flushsize;
1454 	size_t reserved;
1455 	int error = 0;
1456 
1457 	/*
1458 	 * Do a quick check to see if a full flush can be skipped
1459 	 * This assumes that the flush callback does not need to be called
1460 	 * unless there are other outstanding bufs.
1461 	 */
1462 	if (!waitfor) {
1463 		size_t nbufs;
1464 		mutex_enter(&wl->wl_mtx);	/* XXX need mutex here to
1465 						   protect the KASSERTS */
1466 		nbufs = wl->wl_bufcount;
1467 		KASSERT((wl->wl_bufcount == 0) == (wl->wl_bufbytes == 0));
1468 		KASSERT((wl->wl_bufcount == 0) == (wl->wl_bcount == 0));
1469 		mutex_exit(&wl->wl_mtx);
1470 		if (nbufs == 0)
1471 			return 0;
1472 	}
1473 
1474 	/*
1475 	 * XXX we may consider using LK_UPGRADE here
1476 	 * if we want to call flush from inside a transaction
1477 	 */
1478 	rw_enter(&wl->wl_rwlock, RW_WRITER);
1479 	wl->wl_flush(wl->wl_mount, wl->wl_deallocblks, wl->wl_dealloclens,
1480 	    wl->wl_dealloccnt);
1481 
1482 	/*
1483 	 * Now that we are fully locked and flushed,
1484 	 * do another check for nothing to do.
1485 	 */
1486 	if (wl->wl_bufcount == 0) {
1487 		goto out;
1488 	}
1489 
1490 #if 0
1491 	WAPBL_PRINTF(WAPBL_PRINT_FLUSH,
1492 		     ("wapbl_flush thread %d.%d flushing entries with "
1493 		      "bufcount=%zu bufbytes=%zu\n",
1494 		      curproc->p_pid, curlwp->l_lid, wl->wl_bufcount,
1495 		      wl->wl_bufbytes));
1496 #endif
1497 
1498 	/* Calculate amount of space needed to flush */
1499 	flushsize = wapbl_transaction_len(wl);
1500 	if (wapbl_verbose_commit) {
1501 		struct timespec ts;
1502 		getnanotime(&ts);
1503 		printf("%s: %lld.%09ld this transaction = %zu bytes\n",
1504 		    __func__, (long long)ts.tv_sec,
1505 		    (long)ts.tv_nsec, flushsize);
1506 	}
1507 
1508 	if (flushsize > (wl->wl_circ_size - wl->wl_reserved_bytes)) {
1509 		/*
1510 		 * XXX this could be handled more gracefully, perhaps place
1511 		 * only a partial transaction in the log and allow the
1512 		 * remaining to flush without the protection of the journal.
1513 		 */
1514 		panic("wapbl_flush: current transaction too big to flush\n");
1515 	}
1516 
1517 	error = wapbl_truncate(wl, flushsize, 0);
1518 	if (error)
1519 		goto out2;
1520 
1521 	off = wl->wl_head;
1522 	KASSERT((off == 0) || ((off >= wl->wl_circ_off) &&
1523 	                      (off < wl->wl_circ_off + wl->wl_circ_size)));
1524 	error = wapbl_write_blocks(wl, &off);
1525 	if (error)
1526 		goto out2;
1527 	error = wapbl_write_revocations(wl, &off);
1528 	if (error)
1529 		goto out2;
1530 	error = wapbl_write_inodes(wl, &off);
1531 	if (error)
1532 		goto out2;
1533 
1534 	reserved = 0;
1535 	if (wl->wl_inohashcnt)
1536 		reserved = wapbl_transaction_inodes_len(wl);
1537 
1538 	head = wl->wl_head;
1539 	tail = wl->wl_tail;
1540 
1541 	wapbl_advance_head(wl->wl_circ_size, wl->wl_circ_off, flushsize,
1542 	    &head, &tail);
1543 #ifdef WAPBL_DEBUG
1544 	if (head != off) {
1545 		panic("lost head! head=%"PRIdMAX" tail=%" PRIdMAX
1546 		      " off=%"PRIdMAX" flush=%zu\n",
1547 		      (intmax_t)head, (intmax_t)tail, (intmax_t)off,
1548 		      flushsize);
1549 	}
1550 #else
1551 	KASSERT(head == off);
1552 #endif
1553 
1554 	/* Opportunistically move the tail forward if we can */
1555 	if (!wapbl_lazy_truncate) {
1556 		mutex_enter(&wl->wl_mtx);
1557 		delta = wl->wl_reclaimable_bytes;
1558 		mutex_exit(&wl->wl_mtx);
1559 		wapbl_advance_tail(wl->wl_circ_size, wl->wl_circ_off, delta,
1560 		    &head, &tail);
1561 	}
1562 
1563 	error = wapbl_write_commit(wl, head, tail);
1564 	if (error)
1565 		goto out2;
1566 
1567 	we = pool_get(&wapbl_entry_pool, PR_WAITOK);
1568 
1569 #ifdef WAPBL_DEBUG_BUFBYTES
1570 	WAPBL_PRINTF(WAPBL_PRINT_FLUSH,
1571 		("wapbl_flush: thread %d.%d head+=%zu tail+=%zu used=%zu"
1572 		 " unsynced=%zu"
1573 		 "\n\tbufcount=%zu bufbytes=%zu bcount=%zu deallocs=%d "
1574 		 "inodes=%d\n",
1575 		 curproc->p_pid, curlwp->l_lid, flushsize, delta,
1576 		 wapbl_space_used(wl->wl_circ_size, head, tail),
1577 		 wl->wl_unsynced_bufbytes, wl->wl_bufcount,
1578 		 wl->wl_bufbytes, wl->wl_bcount, wl->wl_dealloccnt,
1579 		 wl->wl_inohashcnt));
1580 #else
1581 	WAPBL_PRINTF(WAPBL_PRINT_FLUSH,
1582 		("wapbl_flush: thread %d.%d head+=%zu tail+=%zu used=%zu"
1583 		 "\n\tbufcount=%zu bufbytes=%zu bcount=%zu deallocs=%d "
1584 		 "inodes=%d\n",
1585 		 curproc->p_pid, curlwp->l_lid, flushsize, delta,
1586 		 wapbl_space_used(wl->wl_circ_size, head, tail),
1587 		 wl->wl_bufcount, wl->wl_bufbytes, wl->wl_bcount,
1588 		 wl->wl_dealloccnt, wl->wl_inohashcnt));
1589 #endif
1590 
1591 
1592 	mutex_enter(&bufcache_lock);
1593 	mutex_enter(&wl->wl_mtx);
1594 
1595 	wl->wl_reserved_bytes = reserved;
1596 	wl->wl_head = head;
1597 	wl->wl_tail = tail;
1598 	KASSERT(wl->wl_reclaimable_bytes >= delta);
1599 	wl->wl_reclaimable_bytes -= delta;
1600 	wl->wl_dealloccnt = 0;
1601 #ifdef WAPBL_DEBUG_BUFBYTES
1602 	wl->wl_unsynced_bufbytes += wl->wl_bufbytes;
1603 #endif
1604 
1605 	we->we_wapbl = wl;
1606 	we->we_bufcount = wl->wl_bufcount;
1607 #ifdef WAPBL_DEBUG_BUFBYTES
1608 	we->we_unsynced_bufbytes = wl->wl_bufbytes;
1609 #endif
1610 	we->we_reclaimable_bytes = flushsize;
1611 	we->we_error = 0;
1612 	SIMPLEQ_INSERT_TAIL(&wl->wl_entries, we, we_entries);
1613 
1614 	/*
1615 	 * this flushes bufs in reverse order than they were queued
1616 	 * it shouldn't matter, but if we care we could use TAILQ instead.
1617 	 * XXX Note they will get put on the lru queue when they flush
1618 	 * so we might actually want to change this to preserve order.
1619 	 */
1620 	while ((bp = LIST_FIRST(&wl->wl_bufs)) != NULL) {
1621 		if (bbusy(bp, 0, 0, &wl->wl_mtx)) {
1622 			continue;
1623 		}
1624 		bp->b_iodone = wapbl_biodone;
1625 		bp->b_private = we;
1626 		bremfree(bp);
1627 		wapbl_remove_buf_locked(wl, bp);
1628 		mutex_exit(&wl->wl_mtx);
1629 		mutex_exit(&bufcache_lock);
1630 		bawrite(bp);
1631 		mutex_enter(&bufcache_lock);
1632 		mutex_enter(&wl->wl_mtx);
1633 	}
1634 	mutex_exit(&wl->wl_mtx);
1635 	mutex_exit(&bufcache_lock);
1636 
1637 #if 0
1638 	WAPBL_PRINTF(WAPBL_PRINT_FLUSH,
1639 		     ("wapbl_flush thread %d.%d done flushing entries...\n",
1640 		     curproc->p_pid, curlwp->l_lid));
1641 #endif
1642 
1643  out:
1644 
1645 	/*
1646 	 * If the waitfor flag is set, don't return until everything is
1647 	 * fully flushed and the on disk log is empty.
1648 	 */
1649 	if (waitfor) {
1650 		error = wapbl_truncate(wl, wl->wl_circ_size -
1651 			wl->wl_reserved_bytes, wapbl_lazy_truncate);
1652 	}
1653 
1654  out2:
1655 	if (error) {
1656 		wl->wl_flush_abort(wl->wl_mount, wl->wl_deallocblks,
1657 		    wl->wl_dealloclens, wl->wl_dealloccnt);
1658 	}
1659 
1660 #ifdef WAPBL_DEBUG_PRINT
1661 	if (error) {
1662 		pid_t pid = -1;
1663 		lwpid_t lid = -1;
1664 		if (curproc)
1665 			pid = curproc->p_pid;
1666 		if (curlwp)
1667 			lid = curlwp->l_lid;
1668 		mutex_enter(&wl->wl_mtx);
1669 #ifdef WAPBL_DEBUG_BUFBYTES
1670 		WAPBL_PRINTF(WAPBL_PRINT_ERROR,
1671 		    ("wapbl_flush: thread %d.%d aborted flush: "
1672 		    "error = %d\n"
1673 		    "\tbufcount=%zu bufbytes=%zu bcount=%zu "
1674 		    "deallocs=%d inodes=%d\n"
1675 		    "\terrcnt = %d, reclaimable=%zu reserved=%zu "
1676 		    "unsynced=%zu\n",
1677 		    pid, lid, error, wl->wl_bufcount,
1678 		    wl->wl_bufbytes, wl->wl_bcount,
1679 		    wl->wl_dealloccnt, wl->wl_inohashcnt,
1680 		    wl->wl_error_count, wl->wl_reclaimable_bytes,
1681 		    wl->wl_reserved_bytes, wl->wl_unsynced_bufbytes));
1682 		SIMPLEQ_FOREACH(we, &wl->wl_entries, we_entries) {
1683 			WAPBL_PRINTF(WAPBL_PRINT_ERROR,
1684 			    ("\tentry: bufcount = %zu, reclaimable = %zu, "
1685 			     "error = %d, unsynced = %zu\n",
1686 			     we->we_bufcount, we->we_reclaimable_bytes,
1687 			     we->we_error, we->we_unsynced_bufbytes));
1688 		}
1689 #else
1690 		WAPBL_PRINTF(WAPBL_PRINT_ERROR,
1691 		    ("wapbl_flush: thread %d.%d aborted flush: "
1692 		     "error = %d\n"
1693 		     "\tbufcount=%zu bufbytes=%zu bcount=%zu "
1694 		     "deallocs=%d inodes=%d\n"
1695 		     "\terrcnt = %d, reclaimable=%zu reserved=%zu\n",
1696 		     pid, lid, error, wl->wl_bufcount,
1697 		     wl->wl_bufbytes, wl->wl_bcount,
1698 		     wl->wl_dealloccnt, wl->wl_inohashcnt,
1699 		     wl->wl_error_count, wl->wl_reclaimable_bytes,
1700 		     wl->wl_reserved_bytes));
1701 		SIMPLEQ_FOREACH(we, &wl->wl_entries, we_entries) {
1702 			WAPBL_PRINTF(WAPBL_PRINT_ERROR,
1703 			    ("\tentry: bufcount = %zu, reclaimable = %zu, "
1704 			     "error = %d\n", we->we_bufcount,
1705 			     we->we_reclaimable_bytes, we->we_error));
1706 		}
1707 #endif
1708 		mutex_exit(&wl->wl_mtx);
1709 	}
1710 #endif
1711 
1712 	rw_exit(&wl->wl_rwlock);
1713 	return error;
1714 }
1715 
1716 /****************************************************************/
1717 
1718 void
1719 wapbl_jlock_assert(struct wapbl *wl)
1720 {
1721 
1722 	KASSERT(rw_lock_held(&wl->wl_rwlock));
1723 }
1724 
1725 void
1726 wapbl_junlock_assert(struct wapbl *wl)
1727 {
1728 
1729 	KASSERT(!rw_write_held(&wl->wl_rwlock));
1730 }
1731 
1732 /****************************************************************/
1733 
1734 /* locks missing */
1735 void
1736 wapbl_print(struct wapbl *wl,
1737 		int full,
1738 		void (*pr)(const char *, ...))
1739 {
1740 	struct buf *bp;
1741 	struct wapbl_entry *we;
1742 	(*pr)("wapbl %p", wl);
1743 	(*pr)("\nlogvp = %p, devvp = %p, logpbn = %"PRId64"\n",
1744 	      wl->wl_logvp, wl->wl_devvp, wl->wl_logpbn);
1745 	(*pr)("circ = %zu, header = %zu, head = %"PRIdMAX" tail = %"PRIdMAX"\n",
1746 	      wl->wl_circ_size, wl->wl_circ_off,
1747 	      (intmax_t)wl->wl_head, (intmax_t)wl->wl_tail);
1748 	(*pr)("fs_dev_bshift = %d, log_dev_bshift = %d\n",
1749 	      wl->wl_log_dev_bshift, wl->wl_fs_dev_bshift);
1750 #ifdef WAPBL_DEBUG_BUFBYTES
1751 	(*pr)("bufcount = %zu, bufbytes = %zu bcount = %zu reclaimable = %zu "
1752 	      "reserved = %zu errcnt = %d unsynced = %zu\n",
1753 	      wl->wl_bufcount, wl->wl_bufbytes, wl->wl_bcount,
1754 	      wl->wl_reclaimable_bytes, wl->wl_reserved_bytes,
1755 				wl->wl_error_count, wl->wl_unsynced_bufbytes);
1756 #else
1757 	(*pr)("bufcount = %zu, bufbytes = %zu bcount = %zu reclaimable = %zu "
1758 	      "reserved = %zu errcnt = %d\n", wl->wl_bufcount, wl->wl_bufbytes,
1759 	      wl->wl_bcount, wl->wl_reclaimable_bytes, wl->wl_reserved_bytes,
1760 				wl->wl_error_count);
1761 #endif
1762 	(*pr)("\tdealloccnt = %d, dealloclim = %d\n",
1763 	      wl->wl_dealloccnt, wl->wl_dealloclim);
1764 	(*pr)("\tinohashcnt = %d, inohashmask = 0x%08x\n",
1765 	      wl->wl_inohashcnt, wl->wl_inohashmask);
1766 	(*pr)("entries:\n");
1767 	SIMPLEQ_FOREACH(we, &wl->wl_entries, we_entries) {
1768 #ifdef WAPBL_DEBUG_BUFBYTES
1769 		(*pr)("\tbufcount = %zu, reclaimable = %zu, error = %d, "
1770 		      "unsynced = %zu\n",
1771 		      we->we_bufcount, we->we_reclaimable_bytes,
1772 		      we->we_error, we->we_unsynced_bufbytes);
1773 #else
1774 		(*pr)("\tbufcount = %zu, reclaimable = %zu, error = %d\n",
1775 		      we->we_bufcount, we->we_reclaimable_bytes, we->we_error);
1776 #endif
1777 	}
1778 	if (full) {
1779 		int cnt = 0;
1780 		(*pr)("bufs =");
1781 		LIST_FOREACH(bp, &wl->wl_bufs, b_wapbllist) {
1782 			if (!LIST_NEXT(bp, b_wapbllist)) {
1783 				(*pr)(" %p", bp);
1784 			} else if ((++cnt % 6) == 0) {
1785 				(*pr)(" %p,\n\t", bp);
1786 			} else {
1787 				(*pr)(" %p,", bp);
1788 			}
1789 		}
1790 		(*pr)("\n");
1791 
1792 		(*pr)("dealloced blks = ");
1793 		{
1794 			int i;
1795 			cnt = 0;
1796 			for (i = 0; i < wl->wl_dealloccnt; i++) {
1797 				(*pr)(" %"PRId64":%d,",
1798 				      wl->wl_deallocblks[i],
1799 				      wl->wl_dealloclens[i]);
1800 				if ((++cnt % 4) == 0) {
1801 					(*pr)("\n\t");
1802 				}
1803 			}
1804 		}
1805 		(*pr)("\n");
1806 
1807 		(*pr)("registered inodes = ");
1808 		{
1809 			int i;
1810 			cnt = 0;
1811 			for (i = 0; i <= wl->wl_inohashmask; i++) {
1812 				struct wapbl_ino_head *wih;
1813 				struct wapbl_ino *wi;
1814 
1815 				wih = &wl->wl_inohash[i];
1816 				LIST_FOREACH(wi, wih, wi_hash) {
1817 					if (wi->wi_ino == 0)
1818 						continue;
1819 					(*pr)(" %"PRIu64"/0%06"PRIo32",",
1820 					    wi->wi_ino, wi->wi_mode);
1821 					if ((++cnt % 4) == 0) {
1822 						(*pr)("\n\t");
1823 					}
1824 				}
1825 			}
1826 			(*pr)("\n");
1827 		}
1828 	}
1829 }
1830 
1831 #if defined(WAPBL_DEBUG) || defined(DDB)
1832 void
1833 wapbl_dump(struct wapbl *wl)
1834 {
1835 #if defined(WAPBL_DEBUG)
1836 	if (!wl)
1837 		wl = wapbl_debug_wl;
1838 #endif
1839 	if (!wl)
1840 		return;
1841 	wapbl_print(wl, 1, printf);
1842 }
1843 #endif
1844 
1845 /****************************************************************/
1846 
1847 void
1848 wapbl_register_deallocation(struct wapbl *wl, daddr_t blk, int len)
1849 {
1850 
1851 	wapbl_jlock_assert(wl);
1852 
1853 	mutex_enter(&wl->wl_mtx);
1854 	/* XXX should eventually instead tie this into resource estimation */
1855 	/*
1856 	 * XXX this panic needs locking/mutex analysis and the
1857 	 * ability to cope with the failure.
1858 	 */
1859 	/* XXX this XXX doesn't have enough XXX */
1860 	if (__predict_false(wl->wl_dealloccnt >= wl->wl_dealloclim))
1861 		panic("wapbl_register_deallocation: out of resources");
1862 
1863 	wl->wl_deallocblks[wl->wl_dealloccnt] = blk;
1864 	wl->wl_dealloclens[wl->wl_dealloccnt] = len;
1865 	wl->wl_dealloccnt++;
1866 	WAPBL_PRINTF(WAPBL_PRINT_ALLOC,
1867 	    ("wapbl_register_deallocation: blk=%"PRId64" len=%d\n", blk, len));
1868 	mutex_exit(&wl->wl_mtx);
1869 }
1870 
1871 /****************************************************************/
1872 
1873 static void
1874 wapbl_inodetrk_init(struct wapbl *wl, u_int size)
1875 {
1876 
1877 	wl->wl_inohash = hashinit(size, HASH_LIST, true, &wl->wl_inohashmask);
1878 	if (atomic_inc_uint_nv(&wapbl_ino_pool_refcount) == 1) {
1879 		pool_init(&wapbl_ino_pool, sizeof(struct wapbl_ino), 0, 0, 0,
1880 		    "wapblinopl", &pool_allocator_nointr, IPL_NONE);
1881 	}
1882 }
1883 
1884 static void
1885 wapbl_inodetrk_free(struct wapbl *wl)
1886 {
1887 
1888 	/* XXX this KASSERT needs locking/mutex analysis */
1889 	KASSERT(wl->wl_inohashcnt == 0);
1890 	hashdone(wl->wl_inohash, HASH_LIST, wl->wl_inohashmask);
1891 	if (atomic_dec_uint_nv(&wapbl_ino_pool_refcount) == 0) {
1892 		pool_destroy(&wapbl_ino_pool);
1893 	}
1894 }
1895 
1896 static struct wapbl_ino *
1897 wapbl_inodetrk_get(struct wapbl *wl, ino_t ino)
1898 {
1899 	struct wapbl_ino_head *wih;
1900 	struct wapbl_ino *wi;
1901 
1902 	KASSERT(mutex_owned(&wl->wl_mtx));
1903 
1904 	wih = &wl->wl_inohash[ino & wl->wl_inohashmask];
1905 	LIST_FOREACH(wi, wih, wi_hash) {
1906 		if (ino == wi->wi_ino)
1907 			return wi;
1908 	}
1909 	return 0;
1910 }
1911 
1912 void
1913 wapbl_register_inode(struct wapbl *wl, ino_t ino, mode_t mode)
1914 {
1915 	struct wapbl_ino_head *wih;
1916 	struct wapbl_ino *wi;
1917 
1918 	wi = pool_get(&wapbl_ino_pool, PR_WAITOK);
1919 
1920 	mutex_enter(&wl->wl_mtx);
1921 	if (wapbl_inodetrk_get(wl, ino) == NULL) {
1922 		wi->wi_ino = ino;
1923 		wi->wi_mode = mode;
1924 		wih = &wl->wl_inohash[ino & wl->wl_inohashmask];
1925 		LIST_INSERT_HEAD(wih, wi, wi_hash);
1926 		wl->wl_inohashcnt++;
1927 		WAPBL_PRINTF(WAPBL_PRINT_INODE,
1928 		    ("wapbl_register_inode: ino=%"PRId64"\n", ino));
1929 		mutex_exit(&wl->wl_mtx);
1930 	} else {
1931 		mutex_exit(&wl->wl_mtx);
1932 		pool_put(&wapbl_ino_pool, wi);
1933 	}
1934 }
1935 
1936 void
1937 wapbl_unregister_inode(struct wapbl *wl, ino_t ino, mode_t mode)
1938 {
1939 	struct wapbl_ino *wi;
1940 
1941 	mutex_enter(&wl->wl_mtx);
1942 	wi = wapbl_inodetrk_get(wl, ino);
1943 	if (wi) {
1944 		WAPBL_PRINTF(WAPBL_PRINT_INODE,
1945 		    ("wapbl_unregister_inode: ino=%"PRId64"\n", ino));
1946 		KASSERT(wl->wl_inohashcnt > 0);
1947 		wl->wl_inohashcnt--;
1948 		LIST_REMOVE(wi, wi_hash);
1949 		mutex_exit(&wl->wl_mtx);
1950 
1951 		pool_put(&wapbl_ino_pool, wi);
1952 	} else {
1953 		mutex_exit(&wl->wl_mtx);
1954 	}
1955 }
1956 
1957 /****************************************************************/
1958 
1959 static inline size_t
1960 wapbl_transaction_inodes_len(struct wapbl *wl)
1961 {
1962 	int blocklen = 1<<wl->wl_log_dev_bshift;
1963 	int iph;
1964 
1965 	/* Calculate number of inodes described in a inodelist header */
1966 	iph = (blocklen - offsetof(struct wapbl_wc_inodelist, wc_inodes)) /
1967 	    sizeof(((struct wapbl_wc_inodelist *)0)->wc_inodes[0]);
1968 
1969 	KASSERT(iph > 0);
1970 
1971 	return MAX(1, howmany(wl->wl_inohashcnt, iph)) * blocklen;
1972 }
1973 
1974 
1975 /* Calculate amount of space a transaction will take on disk */
1976 static size_t
1977 wapbl_transaction_len(struct wapbl *wl)
1978 {
1979 	int blocklen = 1<<wl->wl_log_dev_bshift;
1980 	size_t len;
1981 	int bph;
1982 
1983 	/* Calculate number of blocks described in a blocklist header */
1984 	bph = (blocklen - offsetof(struct wapbl_wc_blocklist, wc_blocks)) /
1985 	    sizeof(((struct wapbl_wc_blocklist *)0)->wc_blocks[0]);
1986 
1987 	KASSERT(bph > 0);
1988 
1989 	len = wl->wl_bcount;
1990 	len += howmany(wl->wl_bufcount, bph) * blocklen;
1991 	len += howmany(wl->wl_dealloccnt, bph) * blocklen;
1992 	len += wapbl_transaction_inodes_len(wl);
1993 
1994 	return len;
1995 }
1996 
1997 /*
1998  * wapbl_cache_sync: issue DIOCCACHESYNC
1999  */
2000 static int
2001 wapbl_cache_sync(struct wapbl *wl, const char *msg)
2002 {
2003 	const bool verbose = wapbl_verbose_commit >= 2;
2004 	struct bintime start_time;
2005 	int force = 1;
2006 	int error;
2007 
2008 	if (!wapbl_flush_disk_cache) {
2009 		return 0;
2010 	}
2011 	if (verbose) {
2012 		bintime(&start_time);
2013 	}
2014 	error = VOP_IOCTL(wl->wl_devvp, DIOCCACHESYNC, &force,
2015 	    FWRITE, FSCRED);
2016 	if (error) {
2017 		WAPBL_PRINTF(WAPBL_PRINT_ERROR,
2018 		    ("wapbl_cache_sync: DIOCCACHESYNC on dev 0x%x "
2019 		    "returned %d\n", wl->wl_devvp->v_rdev, error));
2020 	}
2021 	if (verbose) {
2022 		struct bintime d;
2023 		struct timespec ts;
2024 
2025 		bintime(&d);
2026 		bintime_sub(&d, &start_time);
2027 		bintime2timespec(&d, &ts);
2028 		printf("wapbl_cache_sync: %s: dev 0x%jx %ju.%09lu\n",
2029 		    msg, (uintmax_t)wl->wl_devvp->v_rdev,
2030 		    (uintmax_t)ts.tv_sec, ts.tv_nsec);
2031 	}
2032 	return error;
2033 }
2034 
2035 /*
2036  * Perform commit operation
2037  *
2038  * Note that generation number incrementation needs to
2039  * be protected against racing with other invocations
2040  * of wapbl_write_commit.  This is ok since this routine
2041  * is only invoked from wapbl_flush
2042  */
2043 static int
2044 wapbl_write_commit(struct wapbl *wl, off_t head, off_t tail)
2045 {
2046 	struct wapbl_wc_header *wc = wl->wl_wc_header;
2047 	struct timespec ts;
2048 	int error;
2049 	daddr_t pbn;
2050 
2051 	error = wapbl_buffered_flush(wl);
2052 	if (error)
2053 		return error;
2054 	/*
2055 	 * flush disk cache to ensure that blocks we've written are actually
2056 	 * written to the stable storage before the commit header.
2057 	 *
2058 	 * XXX Calc checksum here, instead we do this for now
2059 	 */
2060 	wapbl_cache_sync(wl, "1");
2061 
2062 	wc->wc_head = head;
2063 	wc->wc_tail = tail;
2064 	wc->wc_checksum = 0;
2065 	wc->wc_version = 1;
2066 	getnanotime(&ts);
2067 	wc->wc_time = ts.tv_sec;
2068 	wc->wc_timensec = ts.tv_nsec;
2069 
2070 	WAPBL_PRINTF(WAPBL_PRINT_WRITE,
2071 	    ("wapbl_write_commit: head = %"PRIdMAX "tail = %"PRIdMAX"\n",
2072 	    (intmax_t)head, (intmax_t)tail));
2073 
2074 	/*
2075 	 * write the commit header.
2076 	 *
2077 	 * XXX if generation will rollover, then first zero
2078 	 * over second commit header before trying to write both headers.
2079 	 */
2080 
2081 	pbn = wl->wl_logpbn + (wc->wc_generation % 2);
2082 #ifdef _KERNEL
2083 	pbn = btodb(pbn << wc->wc_log_dev_bshift);
2084 #endif
2085 	error = wapbl_buffered_write(wc, wc->wc_len, wl, pbn);
2086 	if (error)
2087 		return error;
2088 	error = wapbl_buffered_flush(wl);
2089 	if (error)
2090 		return error;
2091 
2092 	/*
2093 	 * flush disk cache to ensure that the commit header is actually
2094 	 * written before meta data blocks.
2095 	 */
2096 	wapbl_cache_sync(wl, "2");
2097 
2098 	/*
2099 	 * If the generation number was zero, write it out a second time.
2100 	 * This handles initialization and generation number rollover
2101 	 */
2102 	if (wc->wc_generation++ == 0) {
2103 		error = wapbl_write_commit(wl, head, tail);
2104 		/*
2105 		 * This panic should be able to be removed if we do the
2106 		 * zero'ing mentioned above, and we are certain to roll
2107 		 * back generation number on failure.
2108 		 */
2109 		if (error)
2110 			panic("wapbl_write_commit: error writing duplicate "
2111 			      "log header: %d\n", error);
2112 	}
2113 	return 0;
2114 }
2115 
2116 /* Returns new offset value */
2117 static int
2118 wapbl_write_blocks(struct wapbl *wl, off_t *offp)
2119 {
2120 	struct wapbl_wc_blocklist *wc =
2121 	    (struct wapbl_wc_blocklist *)wl->wl_wc_scratch;
2122 	int blocklen = 1<<wl->wl_log_dev_bshift;
2123 	int bph;
2124 	struct buf *bp;
2125 	off_t off = *offp;
2126 	int error;
2127 	size_t padding;
2128 
2129 	KASSERT(rw_write_held(&wl->wl_rwlock));
2130 
2131 	bph = (blocklen - offsetof(struct wapbl_wc_blocklist, wc_blocks)) /
2132 	    sizeof(((struct wapbl_wc_blocklist *)0)->wc_blocks[0]);
2133 
2134 	bp = LIST_FIRST(&wl->wl_bufs);
2135 
2136 	while (bp) {
2137 		int cnt;
2138 		struct buf *obp = bp;
2139 
2140 		KASSERT(bp->b_flags & B_LOCKED);
2141 
2142 		wc->wc_type = WAPBL_WC_BLOCKS;
2143 		wc->wc_len = blocklen;
2144 		wc->wc_blkcount = 0;
2145 		while (bp && (wc->wc_blkcount < bph)) {
2146 			/*
2147 			 * Make sure all the physical block numbers are up to
2148 			 * date.  If this is not always true on a given
2149 			 * filesystem, then VOP_BMAP must be called.  We
2150 			 * could call VOP_BMAP here, or else in the filesystem
2151 			 * specific flush callback, although neither of those
2152 			 * solutions allow us to take the vnode lock.  If a
2153 			 * filesystem requires that we must take the vnode lock
2154 			 * to call VOP_BMAP, then we can probably do it in
2155 			 * bwrite when the vnode lock should already be held
2156 			 * by the invoking code.
2157 			 */
2158 			KASSERT((bp->b_vp->v_type == VBLK) ||
2159 				 (bp->b_blkno != bp->b_lblkno));
2160 			KASSERT(bp->b_blkno > 0);
2161 
2162 			wc->wc_blocks[wc->wc_blkcount].wc_daddr = bp->b_blkno;
2163 			wc->wc_blocks[wc->wc_blkcount].wc_dlen = bp->b_bcount;
2164 			wc->wc_len += bp->b_bcount;
2165 			wc->wc_blkcount++;
2166 			bp = LIST_NEXT(bp, b_wapbllist);
2167 		}
2168 		if (wc->wc_len % blocklen != 0) {
2169 			padding = blocklen - wc->wc_len % blocklen;
2170 			wc->wc_len += padding;
2171 		} else {
2172 			padding = 0;
2173 		}
2174 
2175 		WAPBL_PRINTF(WAPBL_PRINT_WRITE,
2176 		    ("wapbl_write_blocks: len = %u (padding %zu) off = %"PRIdMAX"\n",
2177 		    wc->wc_len, padding, (intmax_t)off));
2178 
2179 		error = wapbl_circ_write(wl, wc, blocklen, &off);
2180 		if (error)
2181 			return error;
2182 		bp = obp;
2183 		cnt = 0;
2184 		while (bp && (cnt++ < bph)) {
2185 			error = wapbl_circ_write(wl, bp->b_data,
2186 			    bp->b_bcount, &off);
2187 			if (error)
2188 				return error;
2189 			bp = LIST_NEXT(bp, b_wapbllist);
2190 		}
2191 		if (padding) {
2192 			void *zero;
2193 
2194 			zero = wapbl_alloc(padding);
2195 			memset(zero, 0, padding);
2196 			error = wapbl_circ_write(wl, zero, padding, &off);
2197 			wapbl_free(zero, padding);
2198 			if (error)
2199 				return error;
2200 		}
2201 	}
2202 	*offp = off;
2203 	return 0;
2204 }
2205 
2206 static int
2207 wapbl_write_revocations(struct wapbl *wl, off_t *offp)
2208 {
2209 	struct wapbl_wc_blocklist *wc =
2210 	    (struct wapbl_wc_blocklist *)wl->wl_wc_scratch;
2211 	int i;
2212 	int blocklen = 1<<wl->wl_log_dev_bshift;
2213 	int bph;
2214 	off_t off = *offp;
2215 	int error;
2216 
2217 	if (wl->wl_dealloccnt == 0)
2218 		return 0;
2219 
2220 	bph = (blocklen - offsetof(struct wapbl_wc_blocklist, wc_blocks)) /
2221 	    sizeof(((struct wapbl_wc_blocklist *)0)->wc_blocks[0]);
2222 
2223 	i = 0;
2224 	while (i < wl->wl_dealloccnt) {
2225 		wc->wc_type = WAPBL_WC_REVOCATIONS;
2226 		wc->wc_len = blocklen;
2227 		wc->wc_blkcount = 0;
2228 		while ((i < wl->wl_dealloccnt) && (wc->wc_blkcount < bph)) {
2229 			wc->wc_blocks[wc->wc_blkcount].wc_daddr =
2230 			    wl->wl_deallocblks[i];
2231 			wc->wc_blocks[wc->wc_blkcount].wc_dlen =
2232 			    wl->wl_dealloclens[i];
2233 			wc->wc_blkcount++;
2234 			i++;
2235 		}
2236 		WAPBL_PRINTF(WAPBL_PRINT_WRITE,
2237 		    ("wapbl_write_revocations: len = %u off = %"PRIdMAX"\n",
2238 		    wc->wc_len, (intmax_t)off));
2239 		error = wapbl_circ_write(wl, wc, blocklen, &off);
2240 		if (error)
2241 			return error;
2242 	}
2243 	*offp = off;
2244 	return 0;
2245 }
2246 
2247 static int
2248 wapbl_write_inodes(struct wapbl *wl, off_t *offp)
2249 {
2250 	struct wapbl_wc_inodelist *wc =
2251 	    (struct wapbl_wc_inodelist *)wl->wl_wc_scratch;
2252 	int i;
2253 	int blocklen = 1 << wl->wl_log_dev_bshift;
2254 	off_t off = *offp;
2255 	int error;
2256 
2257 	struct wapbl_ino_head *wih;
2258 	struct wapbl_ino *wi;
2259 	int iph;
2260 
2261 	iph = (blocklen - offsetof(struct wapbl_wc_inodelist, wc_inodes)) /
2262 	    sizeof(((struct wapbl_wc_inodelist *)0)->wc_inodes[0]);
2263 
2264 	i = 0;
2265 	wih = &wl->wl_inohash[0];
2266 	wi = 0;
2267 	do {
2268 		wc->wc_type = WAPBL_WC_INODES;
2269 		wc->wc_len = blocklen;
2270 		wc->wc_inocnt = 0;
2271 		wc->wc_clear = (i == 0);
2272 		while ((i < wl->wl_inohashcnt) && (wc->wc_inocnt < iph)) {
2273 			while (!wi) {
2274 				KASSERT((wih - &wl->wl_inohash[0])
2275 				    <= wl->wl_inohashmask);
2276 				wi = LIST_FIRST(wih++);
2277 			}
2278 			wc->wc_inodes[wc->wc_inocnt].wc_inumber = wi->wi_ino;
2279 			wc->wc_inodes[wc->wc_inocnt].wc_imode = wi->wi_mode;
2280 			wc->wc_inocnt++;
2281 			i++;
2282 			wi = LIST_NEXT(wi, wi_hash);
2283 		}
2284 		WAPBL_PRINTF(WAPBL_PRINT_WRITE,
2285 		    ("wapbl_write_inodes: len = %u off = %"PRIdMAX"\n",
2286 		    wc->wc_len, (intmax_t)off));
2287 		error = wapbl_circ_write(wl, wc, blocklen, &off);
2288 		if (error)
2289 			return error;
2290 	} while (i < wl->wl_inohashcnt);
2291 
2292 	*offp = off;
2293 	return 0;
2294 }
2295 
2296 #endif /* _KERNEL */
2297 
2298 /****************************************************************/
2299 
2300 struct wapbl_blk {
2301 	LIST_ENTRY(wapbl_blk) wb_hash;
2302 	daddr_t wb_blk;
2303 	off_t wb_off; /* Offset of this block in the log */
2304 };
2305 #define	WAPBL_BLKPOOL_MIN 83
2306 
2307 static void
2308 wapbl_blkhash_init(struct wapbl_replay *wr, u_int size)
2309 {
2310 	if (size < WAPBL_BLKPOOL_MIN)
2311 		size = WAPBL_BLKPOOL_MIN;
2312 	KASSERT(wr->wr_blkhash == 0);
2313 #ifdef _KERNEL
2314 	wr->wr_blkhash = hashinit(size, HASH_LIST, true, &wr->wr_blkhashmask);
2315 #else /* ! _KERNEL */
2316 	/* Manually implement hashinit */
2317 	{
2318 		unsigned long i, hashsize;
2319 		for (hashsize = 1; hashsize < size; hashsize <<= 1)
2320 			continue;
2321 		wr->wr_blkhash = wapbl_alloc(hashsize * sizeof(*wr->wr_blkhash));
2322 		for (i = 0; i < hashsize; i++)
2323 			LIST_INIT(&wr->wr_blkhash[i]);
2324 		wr->wr_blkhashmask = hashsize - 1;
2325 	}
2326 #endif /* ! _KERNEL */
2327 }
2328 
2329 static void
2330 wapbl_blkhash_free(struct wapbl_replay *wr)
2331 {
2332 	KASSERT(wr->wr_blkhashcnt == 0);
2333 #ifdef _KERNEL
2334 	hashdone(wr->wr_blkhash, HASH_LIST, wr->wr_blkhashmask);
2335 #else /* ! _KERNEL */
2336 	wapbl_free(wr->wr_blkhash,
2337 	    (wr->wr_blkhashmask + 1) * sizeof(*wr->wr_blkhash));
2338 #endif /* ! _KERNEL */
2339 }
2340 
2341 static struct wapbl_blk *
2342 wapbl_blkhash_get(struct wapbl_replay *wr, daddr_t blk)
2343 {
2344 	struct wapbl_blk_head *wbh;
2345 	struct wapbl_blk *wb;
2346 	wbh = &wr->wr_blkhash[blk & wr->wr_blkhashmask];
2347 	LIST_FOREACH(wb, wbh, wb_hash) {
2348 		if (blk == wb->wb_blk)
2349 			return wb;
2350 	}
2351 	return 0;
2352 }
2353 
2354 static void
2355 wapbl_blkhash_ins(struct wapbl_replay *wr, daddr_t blk, off_t off)
2356 {
2357 	struct wapbl_blk_head *wbh;
2358 	struct wapbl_blk *wb;
2359 	wb = wapbl_blkhash_get(wr, blk);
2360 	if (wb) {
2361 		KASSERT(wb->wb_blk == blk);
2362 		wb->wb_off = off;
2363 	} else {
2364 		wb = wapbl_alloc(sizeof(*wb));
2365 		wb->wb_blk = blk;
2366 		wb->wb_off = off;
2367 		wbh = &wr->wr_blkhash[blk & wr->wr_blkhashmask];
2368 		LIST_INSERT_HEAD(wbh, wb, wb_hash);
2369 		wr->wr_blkhashcnt++;
2370 	}
2371 }
2372 
2373 static void
2374 wapbl_blkhash_rem(struct wapbl_replay *wr, daddr_t blk)
2375 {
2376 	struct wapbl_blk *wb = wapbl_blkhash_get(wr, blk);
2377 	if (wb) {
2378 		KASSERT(wr->wr_blkhashcnt > 0);
2379 		wr->wr_blkhashcnt--;
2380 		LIST_REMOVE(wb, wb_hash);
2381 		wapbl_free(wb, sizeof(*wb));
2382 	}
2383 }
2384 
2385 static void
2386 wapbl_blkhash_clear(struct wapbl_replay *wr)
2387 {
2388 	unsigned long i;
2389 	for (i = 0; i <= wr->wr_blkhashmask; i++) {
2390 		struct wapbl_blk *wb;
2391 
2392 		while ((wb = LIST_FIRST(&wr->wr_blkhash[i]))) {
2393 			KASSERT(wr->wr_blkhashcnt > 0);
2394 			wr->wr_blkhashcnt--;
2395 			LIST_REMOVE(wb, wb_hash);
2396 			wapbl_free(wb, sizeof(*wb));
2397 		}
2398 	}
2399 	KASSERT(wr->wr_blkhashcnt == 0);
2400 }
2401 
2402 /****************************************************************/
2403 
2404 static int
2405 wapbl_circ_read(struct wapbl_replay *wr, void *data, size_t len, off_t *offp)
2406 {
2407 	size_t slen;
2408 	off_t off = *offp;
2409 	int error;
2410 	daddr_t pbn;
2411 
2412 	KASSERT(((len >> wr->wr_log_dev_bshift) <<
2413 	    wr->wr_log_dev_bshift) == len);
2414 
2415 	if (off < wr->wr_circ_off)
2416 		off = wr->wr_circ_off;
2417 	slen = wr->wr_circ_off + wr->wr_circ_size - off;
2418 	if (slen < len) {
2419 		pbn = wr->wr_logpbn + (off >> wr->wr_log_dev_bshift);
2420 #ifdef _KERNEL
2421 		pbn = btodb(pbn << wr->wr_log_dev_bshift);
2422 #endif
2423 		error = wapbl_read(data, slen, wr->wr_devvp, pbn);
2424 		if (error)
2425 			return error;
2426 		data = (uint8_t *)data + slen;
2427 		len -= slen;
2428 		off = wr->wr_circ_off;
2429 	}
2430 	pbn = wr->wr_logpbn + (off >> wr->wr_log_dev_bshift);
2431 #ifdef _KERNEL
2432 	pbn = btodb(pbn << wr->wr_log_dev_bshift);
2433 #endif
2434 	error = wapbl_read(data, len, wr->wr_devvp, pbn);
2435 	if (error)
2436 		return error;
2437 	off += len;
2438 	if (off >= wr->wr_circ_off + wr->wr_circ_size)
2439 		off = wr->wr_circ_off;
2440 	*offp = off;
2441 	return 0;
2442 }
2443 
2444 static void
2445 wapbl_circ_advance(struct wapbl_replay *wr, size_t len, off_t *offp)
2446 {
2447 	size_t slen;
2448 	off_t off = *offp;
2449 
2450 	KASSERT(((len >> wr->wr_log_dev_bshift) <<
2451 	    wr->wr_log_dev_bshift) == len);
2452 
2453 	if (off < wr->wr_circ_off)
2454 		off = wr->wr_circ_off;
2455 	slen = wr->wr_circ_off + wr->wr_circ_size - off;
2456 	if (slen < len) {
2457 		len -= slen;
2458 		off = wr->wr_circ_off;
2459 	}
2460 	off += len;
2461 	if (off >= wr->wr_circ_off + wr->wr_circ_size)
2462 		off = wr->wr_circ_off;
2463 	*offp = off;
2464 }
2465 
2466 /****************************************************************/
2467 
2468 int
2469 wapbl_replay_start(struct wapbl_replay **wrp, struct vnode *vp,
2470 	daddr_t off, size_t count, size_t blksize)
2471 {
2472 	struct wapbl_replay *wr;
2473 	int error;
2474 	struct vnode *devvp;
2475 	daddr_t logpbn;
2476 	uint8_t *scratch;
2477 	struct wapbl_wc_header *wch;
2478 	struct wapbl_wc_header *wch2;
2479 	/* Use this until we read the actual log header */
2480 	int log_dev_bshift = ilog2(blksize);
2481 	size_t used;
2482 	daddr_t pbn;
2483 
2484 	WAPBL_PRINTF(WAPBL_PRINT_REPLAY,
2485 	    ("wapbl_replay_start: vp=%p off=%"PRId64 " count=%zu blksize=%zu\n",
2486 	    vp, off, count, blksize));
2487 
2488 	if (off < 0)
2489 		return EINVAL;
2490 
2491 	if (blksize < DEV_BSIZE)
2492 		return EINVAL;
2493 	if (blksize % DEV_BSIZE)
2494 		return EINVAL;
2495 
2496 #ifdef _KERNEL
2497 #if 0
2498 	/* XXX vp->v_size isn't reliably set for VBLK devices,
2499 	 * especially root.  However, we might still want to verify
2500 	 * that the full load is readable */
2501 	if ((off + count) * blksize > vp->v_size)
2502 		return EINVAL;
2503 #endif
2504 	if ((error = VOP_BMAP(vp, off, &devvp, &logpbn, 0)) != 0) {
2505 		return error;
2506 	}
2507 #else /* ! _KERNEL */
2508 	devvp = vp;
2509 	logpbn = off;
2510 #endif /* ! _KERNEL */
2511 
2512 	scratch = wapbl_alloc(MAXBSIZE);
2513 
2514 	pbn = logpbn;
2515 #ifdef _KERNEL
2516 	pbn = btodb(pbn << log_dev_bshift);
2517 #endif
2518 	error = wapbl_read(scratch, 2<<log_dev_bshift, devvp, pbn);
2519 	if (error)
2520 		goto errout;
2521 
2522 	wch = (struct wapbl_wc_header *)scratch;
2523 	wch2 =
2524 	    (struct wapbl_wc_header *)(scratch + (1<<log_dev_bshift));
2525 	/* XXX verify checksums and magic numbers */
2526 	if (wch->wc_type != WAPBL_WC_HEADER) {
2527 		printf("Unrecognized wapbl magic: 0x%08x\n", wch->wc_type);
2528 		error = EFTYPE;
2529 		goto errout;
2530 	}
2531 
2532 	if (wch2->wc_generation > wch->wc_generation)
2533 		wch = wch2;
2534 
2535 	wr = wapbl_calloc(1, sizeof(*wr));
2536 
2537 	wr->wr_logvp = vp;
2538 	wr->wr_devvp = devvp;
2539 	wr->wr_logpbn = logpbn;
2540 
2541 	wr->wr_scratch = scratch;
2542 
2543 	wr->wr_log_dev_bshift = wch->wc_log_dev_bshift;
2544 	wr->wr_fs_dev_bshift = wch->wc_fs_dev_bshift;
2545 	wr->wr_circ_off = wch->wc_circ_off;
2546 	wr->wr_circ_size = wch->wc_circ_size;
2547 	wr->wr_generation = wch->wc_generation;
2548 
2549 	used = wapbl_space_used(wch->wc_circ_size, wch->wc_head, wch->wc_tail);
2550 
2551 	WAPBL_PRINTF(WAPBL_PRINT_REPLAY,
2552 	    ("wapbl_replay: head=%"PRId64" tail=%"PRId64" off=%"PRId64
2553 	    " len=%"PRId64" used=%zu\n",
2554 	    wch->wc_head, wch->wc_tail, wch->wc_circ_off,
2555 	    wch->wc_circ_size, used));
2556 
2557 	wapbl_blkhash_init(wr, (used >> wch->wc_fs_dev_bshift));
2558 
2559 	error = wapbl_replay_process(wr, wch->wc_head, wch->wc_tail);
2560 	if (error) {
2561 		wapbl_replay_stop(wr);
2562 		wapbl_replay_free(wr);
2563 		return error;
2564 	}
2565 
2566 	*wrp = wr;
2567 	return 0;
2568 
2569  errout:
2570 	wapbl_free(scratch, MAXBSIZE);
2571 	return error;
2572 }
2573 
2574 void
2575 wapbl_replay_stop(struct wapbl_replay *wr)
2576 {
2577 
2578 	if (!wapbl_replay_isopen(wr))
2579 		return;
2580 
2581 	WAPBL_PRINTF(WAPBL_PRINT_REPLAY, ("wapbl_replay_stop called\n"));
2582 
2583 	wapbl_free(wr->wr_scratch, MAXBSIZE);
2584 	wr->wr_scratch = NULL;
2585 
2586 	wr->wr_logvp = NULL;
2587 
2588 	wapbl_blkhash_clear(wr);
2589 	wapbl_blkhash_free(wr);
2590 }
2591 
2592 void
2593 wapbl_replay_free(struct wapbl_replay *wr)
2594 {
2595 
2596 	KDASSERT(!wapbl_replay_isopen(wr));
2597 
2598 	if (wr->wr_inodes)
2599 		wapbl_free(wr->wr_inodes,
2600 		    wr->wr_inodescnt * sizeof(wr->wr_inodes[0]));
2601 	wapbl_free(wr, sizeof(*wr));
2602 }
2603 
2604 #ifdef _KERNEL
2605 int
2606 wapbl_replay_isopen1(struct wapbl_replay *wr)
2607 {
2608 
2609 	return wapbl_replay_isopen(wr);
2610 }
2611 #endif
2612 
2613 static void
2614 wapbl_replay_process_blocks(struct wapbl_replay *wr, off_t *offp)
2615 {
2616 	struct wapbl_wc_blocklist *wc =
2617 	    (struct wapbl_wc_blocklist *)wr->wr_scratch;
2618 	int fsblklen = 1 << wr->wr_fs_dev_bshift;
2619 	int i, j, n;
2620 
2621 	for (i = 0; i < wc->wc_blkcount; i++) {
2622 		/*
2623 		 * Enter each physical block into the hashtable independently.
2624 		 */
2625 		n = wc->wc_blocks[i].wc_dlen >> wr->wr_fs_dev_bshift;
2626 		for (j = 0; j < n; j++) {
2627 			wapbl_blkhash_ins(wr, wc->wc_blocks[i].wc_daddr + btodb(j * fsblklen),
2628 			    *offp);
2629 			wapbl_circ_advance(wr, fsblklen, offp);
2630 		}
2631 	}
2632 }
2633 
2634 static void
2635 wapbl_replay_process_revocations(struct wapbl_replay *wr)
2636 {
2637 	struct wapbl_wc_blocklist *wc =
2638 	    (struct wapbl_wc_blocklist *)wr->wr_scratch;
2639 	int fsblklen = 1 << wr->wr_fs_dev_bshift;
2640 	int i, j, n;
2641 
2642 	for (i = 0; i < wc->wc_blkcount; i++) {
2643 		/*
2644 		 * Remove any blocks found from the hashtable.
2645 		 */
2646 		n = wc->wc_blocks[i].wc_dlen >> wr->wr_fs_dev_bshift;
2647 		for (j = 0; j < n; j++)
2648 			wapbl_blkhash_rem(wr, wc->wc_blocks[i].wc_daddr + btodb(j * fsblklen));
2649 	}
2650 }
2651 
2652 static void
2653 wapbl_replay_process_inodes(struct wapbl_replay *wr, off_t oldoff, off_t newoff)
2654 {
2655 	struct wapbl_wc_inodelist *wc =
2656 	    (struct wapbl_wc_inodelist *)wr->wr_scratch;
2657 	void *new_inodes;
2658 	const size_t oldsize = wr->wr_inodescnt * sizeof(wr->wr_inodes[0]);
2659 
2660 	KASSERT(sizeof(wr->wr_inodes[0]) == sizeof(wc->wc_inodes[0]));
2661 
2662 	/*
2663 	 * Keep track of where we found this so location won't be
2664 	 * overwritten.
2665 	 */
2666 	if (wc->wc_clear) {
2667 		wr->wr_inodestail = oldoff;
2668 		wr->wr_inodescnt = 0;
2669 		if (wr->wr_inodes != NULL) {
2670 			wapbl_free(wr->wr_inodes, oldsize);
2671 			wr->wr_inodes = NULL;
2672 		}
2673 	}
2674 	wr->wr_inodeshead = newoff;
2675 	if (wc->wc_inocnt == 0)
2676 		return;
2677 
2678 	new_inodes = wapbl_alloc((wr->wr_inodescnt + wc->wc_inocnt) *
2679 	    sizeof(wr->wr_inodes[0]));
2680 	if (wr->wr_inodes != NULL) {
2681 		memcpy(new_inodes, wr->wr_inodes, oldsize);
2682 		wapbl_free(wr->wr_inodes, oldsize);
2683 	}
2684 	wr->wr_inodes = new_inodes;
2685 	memcpy(&wr->wr_inodes[wr->wr_inodescnt], wc->wc_inodes,
2686 	    wc->wc_inocnt * sizeof(wr->wr_inodes[0]));
2687 	wr->wr_inodescnt += wc->wc_inocnt;
2688 }
2689 
2690 static int
2691 wapbl_replay_process(struct wapbl_replay *wr, off_t head, off_t tail)
2692 {
2693 	off_t off;
2694 	int error;
2695 
2696 	int logblklen = 1 << wr->wr_log_dev_bshift;
2697 
2698 	wapbl_blkhash_clear(wr);
2699 
2700 	off = tail;
2701 	while (off != head) {
2702 		struct wapbl_wc_null *wcn;
2703 		off_t saveoff = off;
2704 		error = wapbl_circ_read(wr, wr->wr_scratch, logblklen, &off);
2705 		if (error)
2706 			goto errout;
2707 		wcn = (struct wapbl_wc_null *)wr->wr_scratch;
2708 		switch (wcn->wc_type) {
2709 		case WAPBL_WC_BLOCKS:
2710 			wapbl_replay_process_blocks(wr, &off);
2711 			break;
2712 
2713 		case WAPBL_WC_REVOCATIONS:
2714 			wapbl_replay_process_revocations(wr);
2715 			break;
2716 
2717 		case WAPBL_WC_INODES:
2718 			wapbl_replay_process_inodes(wr, saveoff, off);
2719 			break;
2720 
2721 		default:
2722 			printf("Unrecognized wapbl type: 0x%08x\n",
2723 			       wcn->wc_type);
2724  			error = EFTYPE;
2725 			goto errout;
2726 		}
2727 		wapbl_circ_advance(wr, wcn->wc_len, &saveoff);
2728 		if (off != saveoff) {
2729 			printf("wapbl_replay: corrupted records\n");
2730 			error = EFTYPE;
2731 			goto errout;
2732 		}
2733 	}
2734 	return 0;
2735 
2736  errout:
2737 	wapbl_blkhash_clear(wr);
2738 	return error;
2739 }
2740 
2741 #if 0
2742 int
2743 wapbl_replay_verify(struct wapbl_replay *wr, struct vnode *fsdevvp)
2744 {
2745 	off_t off;
2746 	int mismatchcnt = 0;
2747 	int logblklen = 1 << wr->wr_log_dev_bshift;
2748 	int fsblklen = 1 << wr->wr_fs_dev_bshift;
2749 	void *scratch1 = wapbl_alloc(MAXBSIZE);
2750 	void *scratch2 = wapbl_alloc(MAXBSIZE);
2751 	int error = 0;
2752 
2753 	KDASSERT(wapbl_replay_isopen(wr));
2754 
2755 	off = wch->wc_tail;
2756 	while (off != wch->wc_head) {
2757 		struct wapbl_wc_null *wcn;
2758 #ifdef DEBUG
2759 		off_t saveoff = off;
2760 #endif
2761 		error = wapbl_circ_read(wr, wr->wr_scratch, logblklen, &off);
2762 		if (error)
2763 			goto out;
2764 		wcn = (struct wapbl_wc_null *)wr->wr_scratch;
2765 		switch (wcn->wc_type) {
2766 		case WAPBL_WC_BLOCKS:
2767 			{
2768 				struct wapbl_wc_blocklist *wc =
2769 				    (struct wapbl_wc_blocklist *)wr->wr_scratch;
2770 				int i;
2771 				for (i = 0; i < wc->wc_blkcount; i++) {
2772 					int foundcnt = 0;
2773 					int dirtycnt = 0;
2774 					int j, n;
2775 					/*
2776 					 * Check each physical block into the
2777 					 * hashtable independently
2778 					 */
2779 					n = wc->wc_blocks[i].wc_dlen >>
2780 					    wch->wc_fs_dev_bshift;
2781 					for (j = 0; j < n; j++) {
2782 						struct wapbl_blk *wb =
2783 						   wapbl_blkhash_get(wr,
2784 						   wc->wc_blocks[i].wc_daddr + btodb(j * fsblklen));
2785 						if (wb && (wb->wb_off == off)) {
2786 							foundcnt++;
2787 							error =
2788 							    wapbl_circ_read(wr,
2789 							    scratch1, fsblklen,
2790 							    &off);
2791 							if (error)
2792 								goto out;
2793 							error =
2794 							    wapbl_read(scratch2,
2795 							    fsblklen, fsdevvp,
2796 							    wb->wb_blk);
2797 							if (error)
2798 								goto out;
2799 							if (memcmp(scratch1,
2800 								   scratch2,
2801 								   fsblklen)) {
2802 								printf(
2803 		"wapbl_verify: mismatch block %"PRId64" at off %"PRIdMAX"\n",
2804 		wb->wb_blk, (intmax_t)off);
2805 								dirtycnt++;
2806 								mismatchcnt++;
2807 							}
2808 						} else {
2809 							wapbl_circ_advance(wr,
2810 							    fsblklen, &off);
2811 						}
2812 					}
2813 #if 0
2814 					/*
2815 					 * If all of the blocks in an entry
2816 					 * are clean, then remove all of its
2817 					 * blocks from the hashtable since they
2818 					 * never will need replay.
2819 					 */
2820 					if ((foundcnt != 0) &&
2821 					    (dirtycnt == 0)) {
2822 						off = saveoff;
2823 						wapbl_circ_advance(wr,
2824 						    logblklen, &off);
2825 						for (j = 0; j < n; j++) {
2826 							struct wapbl_blk *wb =
2827 							   wapbl_blkhash_get(wr,
2828 							   wc->wc_blocks[i].wc_daddr + btodb(j * fsblklen));
2829 							if (wb &&
2830 							  (wb->wb_off == off)) {
2831 								wapbl_blkhash_rem(wr, wb->wb_blk);
2832 							}
2833 							wapbl_circ_advance(wr,
2834 							    fsblklen, &off);
2835 						}
2836 					}
2837 #endif
2838 				}
2839 			}
2840 			break;
2841 		case WAPBL_WC_REVOCATIONS:
2842 		case WAPBL_WC_INODES:
2843 			break;
2844 		default:
2845 			KASSERT(0);
2846 		}
2847 #ifdef DEBUG
2848 		wapbl_circ_advance(wr, wcn->wc_len, &saveoff);
2849 		KASSERT(off == saveoff);
2850 #endif
2851 	}
2852  out:
2853 	wapbl_free(scratch1, MAXBSIZE);
2854 	wapbl_free(scratch2, MAXBSIZE);
2855 	if (!error && mismatchcnt)
2856 		error = EFTYPE;
2857 	return error;
2858 }
2859 #endif
2860 
2861 int
2862 wapbl_replay_write(struct wapbl_replay *wr, struct vnode *fsdevvp)
2863 {
2864 	struct wapbl_blk *wb;
2865 	size_t i;
2866 	off_t off;
2867 	void *scratch;
2868 	int error = 0;
2869 	int fsblklen = 1 << wr->wr_fs_dev_bshift;
2870 
2871 	KDASSERT(wapbl_replay_isopen(wr));
2872 
2873 	scratch = wapbl_alloc(MAXBSIZE);
2874 
2875 	for (i = 0; i <= wr->wr_blkhashmask; ++i) {
2876 		LIST_FOREACH(wb, &wr->wr_blkhash[i], wb_hash) {
2877 			off = wb->wb_off;
2878 			error = wapbl_circ_read(wr, scratch, fsblklen, &off);
2879 			if (error)
2880 				break;
2881 			error = wapbl_write(scratch, fsblklen, fsdevvp,
2882 			    wb->wb_blk);
2883 			if (error)
2884 				break;
2885 		}
2886 	}
2887 
2888 	wapbl_free(scratch, MAXBSIZE);
2889 	return error;
2890 }
2891 
2892 int
2893 wapbl_replay_can_read(struct wapbl_replay *wr, daddr_t blk, long len)
2894 {
2895 	int fsblklen = 1 << wr->wr_fs_dev_bshift;
2896 
2897 	KDASSERT(wapbl_replay_isopen(wr));
2898 	KASSERT((len % fsblklen) == 0);
2899 
2900 	while (len != 0) {
2901 		struct wapbl_blk *wb = wapbl_blkhash_get(wr, blk);
2902 		if (wb)
2903 			return 1;
2904 		len -= fsblklen;
2905 	}
2906 	return 0;
2907 }
2908 
2909 int
2910 wapbl_replay_read(struct wapbl_replay *wr, void *data, daddr_t blk, long len)
2911 {
2912 	int fsblklen = 1 << wr->wr_fs_dev_bshift;
2913 
2914 	KDASSERT(wapbl_replay_isopen(wr));
2915 
2916 	KASSERT((len % fsblklen) == 0);
2917 
2918 	while (len != 0) {
2919 		struct wapbl_blk *wb = wapbl_blkhash_get(wr, blk);
2920 		if (wb) {
2921 			off_t off = wb->wb_off;
2922 			int error;
2923 			error = wapbl_circ_read(wr, data, fsblklen, &off);
2924 			if (error)
2925 				return error;
2926 		}
2927 		data = (uint8_t *)data + fsblklen;
2928 		len -= fsblklen;
2929 		blk++;
2930 	}
2931 	return 0;
2932 }
2933 
2934 #ifdef _KERNEL
2935 /*
2936  * This is not really a module now, but maybe on it's way to
2937  * being one some day.
2938  */
2939 MODULE(MODULE_CLASS_VFS, wapbl, NULL);
2940 
2941 static int
2942 wapbl_modcmd(modcmd_t cmd, void *arg)
2943 {
2944 
2945 	switch (cmd) {
2946 	case MODULE_CMD_INIT:
2947 		wapbl_init();
2948 		return 0;
2949 	case MODULE_CMD_FINI:
2950 #ifdef notyet
2951 		return wapbl_fini(true);
2952 #endif
2953 		return EOPNOTSUPP;
2954 	default:
2955 		return ENOTTY;
2956 	}
2957 }
2958 #endif /* _KERNEL */
2959