lfs_subr.c revision 1.84 1 /* $NetBSD: lfs_subr.c,v 1.84 2015/07/28 05:09:35 dholland Exp $ */
2
3 /*-
4 * Copyright (c) 1999, 2000, 2001, 2002, 2003 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Konrad E. Schroder <perseant (at) hhhh.org>.
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 * Copyright (c) 1991, 1993
33 * The Regents of the University of California. All rights reserved.
34 *
35 * Redistribution and use in source and binary forms, with or without
36 * modification, are permitted provided that the following conditions
37 * are met:
38 * 1. Redistributions of source code must retain the above copyright
39 * notice, this list of conditions and the following disclaimer.
40 * 2. Redistributions in binary form must reproduce the above copyright
41 * notice, this list of conditions and the following disclaimer in the
42 * documentation and/or other materials provided with the distribution.
43 * 3. Neither the name of the University nor the names of its contributors
44 * may be used to endorse or promote products derived from this software
45 * without specific prior written permission.
46 *
47 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
48 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
49 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
50 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
51 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
52 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
53 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
54 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
55 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
56 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
57 * SUCH DAMAGE.
58 *
59 * @(#)lfs_subr.c 8.4 (Berkeley) 5/8/95
60 */
61
62 #include <sys/cdefs.h>
63 __KERNEL_RCSID(0, "$NetBSD: lfs_subr.c,v 1.84 2015/07/28 05:09:35 dholland Exp $");
64
65 #include <sys/param.h>
66 #include <sys/systm.h>
67 #include <sys/namei.h>
68 #include <sys/vnode.h>
69 #include <sys/buf.h>
70 #include <sys/mount.h>
71 #include <sys/malloc.h>
72 #include <sys/proc.h>
73 #include <sys/kauth.h>
74
75 #include <ufs/lfs/ulfs_inode.h>
76 #include <ufs/lfs/lfs.h>
77 #include <ufs/lfs/lfs_accessors.h>
78 #include <ufs/lfs/lfs_kernel.h>
79 #include <ufs/lfs/lfs_extern.h>
80
81 #include <uvm/uvm.h>
82
83 #ifdef DEBUG
84 const char *lfs_res_names[LFS_NB_COUNT] = {
85 "summary",
86 "superblock",
87 "file block",
88 "cluster",
89 "clean",
90 "blkiov",
91 };
92 #endif
93
94 int lfs_res_qty[LFS_NB_COUNT] = {
95 LFS_N_SUMMARIES,
96 LFS_N_SBLOCKS,
97 LFS_N_IBLOCKS,
98 LFS_N_CLUSTERS,
99 LFS_N_CLEAN,
100 LFS_N_BLKIOV,
101 };
102
103 void
104 lfs_setup_resblks(struct lfs *fs)
105 {
106 int i, j;
107 int maxbpp;
108
109 ASSERT_NO_SEGLOCK(fs);
110 fs->lfs_resblk = malloc(LFS_N_TOTAL * sizeof(res_t), M_SEGMENT,
111 M_WAITOK);
112 for (i = 0; i < LFS_N_TOTAL; i++) {
113 fs->lfs_resblk[i].inuse = 0;
114 fs->lfs_resblk[i].p = NULL;
115 }
116 for (i = 0; i < LFS_RESHASH_WIDTH; i++)
117 LIST_INIT(fs->lfs_reshash + i);
118
119 /*
120 * These types of allocations can be larger than a page,
121 * so we can't use the pool subsystem for them.
122 */
123 for (i = 0, j = 0; j < LFS_N_SUMMARIES; j++, i++)
124 fs->lfs_resblk[i].size = lfs_sb_getsumsize(fs);
125 for (j = 0; j < LFS_N_SBLOCKS; j++, i++)
126 fs->lfs_resblk[i].size = LFS_SBPAD;
127 for (j = 0; j < LFS_N_IBLOCKS; j++, i++)
128 fs->lfs_resblk[i].size = lfs_sb_getbsize(fs);
129 for (j = 0; j < LFS_N_CLUSTERS; j++, i++)
130 fs->lfs_resblk[i].size = MAXPHYS;
131 for (j = 0; j < LFS_N_CLEAN; j++, i++)
132 fs->lfs_resblk[i].size = MAXPHYS;
133 for (j = 0; j < LFS_N_BLKIOV; j++, i++)
134 fs->lfs_resblk[i].size = LFS_MARKV_MAXBLKCNT * sizeof(BLOCK_INFO);
135
136 for (i = 0; i < LFS_N_TOTAL; i++) {
137 fs->lfs_resblk[i].p = malloc(fs->lfs_resblk[i].size,
138 M_SEGMENT, M_WAITOK);
139 }
140
141 /*
142 * Initialize pools for small types (XXX is BPP small?)
143 */
144 pool_init(&fs->lfs_clpool, sizeof(struct lfs_cluster), 0, 0, 0,
145 "lfsclpl", &pool_allocator_nointr, IPL_NONE);
146 pool_init(&fs->lfs_segpool, sizeof(struct segment), 0, 0, 0,
147 "lfssegpool", &pool_allocator_nointr, IPL_NONE);
148 maxbpp = ((lfs_sb_getsumsize(fs) - SEGSUM_SIZE(fs)) / sizeof(int32_t) + 2);
149 maxbpp = MIN(maxbpp, lfs_segsize(fs) / lfs_sb_getfsize(fs) + 2);
150 pool_init(&fs->lfs_bpppool, maxbpp * sizeof(struct buf *), 0, 0, 0,
151 "lfsbpppl", &pool_allocator_nointr, IPL_NONE);
152 }
153
154 void
155 lfs_free_resblks(struct lfs *fs)
156 {
157 int i;
158
159 pool_destroy(&fs->lfs_bpppool);
160 pool_destroy(&fs->lfs_segpool);
161 pool_destroy(&fs->lfs_clpool);
162
163 mutex_enter(&lfs_lock);
164 for (i = 0; i < LFS_N_TOTAL; i++) {
165 while (fs->lfs_resblk[i].inuse)
166 mtsleep(&fs->lfs_resblk, PRIBIO + 1, "lfs_free", 0,
167 &lfs_lock);
168 if (fs->lfs_resblk[i].p != NULL)
169 free(fs->lfs_resblk[i].p, M_SEGMENT);
170 }
171 free(fs->lfs_resblk, M_SEGMENT);
172 mutex_exit(&lfs_lock);
173 }
174
175 static unsigned int
176 lfs_mhash(void *vp)
177 {
178 return (unsigned int)(((unsigned long)vp) >> 2) % LFS_RESHASH_WIDTH;
179 }
180
181 /*
182 * Return memory of the given size for the given purpose, or use one of a
183 * number of spare last-resort buffers, if malloc returns NULL.
184 */
185 void *
186 lfs_malloc(struct lfs *fs, size_t size, int type)
187 {
188 struct lfs_res_blk *re;
189 void *r;
190 int i, s, start;
191 unsigned int h;
192
193 ASSERT_MAYBE_SEGLOCK(fs);
194 r = NULL;
195
196 /* If no mem allocated for this type, it just waits */
197 if (lfs_res_qty[type] == 0) {
198 r = malloc(size, M_SEGMENT, M_WAITOK);
199 return r;
200 }
201
202 /* Otherwise try a quick malloc, and if it works, great */
203 if ((r = malloc(size, M_SEGMENT, M_NOWAIT)) != NULL) {
204 return r;
205 }
206
207 /*
208 * If malloc returned NULL, we are forced to use one of our
209 * reserve blocks. We have on hand at least one summary block,
210 * at least one cluster block, at least one superblock,
211 * and several indirect blocks.
212 */
213
214 mutex_enter(&lfs_lock);
215 /* skip over blocks of other types */
216 for (i = 0, start = 0; i < type; i++)
217 start += lfs_res_qty[i];
218 while (r == NULL) {
219 for (i = 0; i < lfs_res_qty[type]; i++) {
220 if (fs->lfs_resblk[start + i].inuse == 0) {
221 re = fs->lfs_resblk + start + i;
222 re->inuse = 1;
223 r = re->p;
224 KASSERT(re->size >= size);
225 h = lfs_mhash(r);
226 s = splbio();
227 LIST_INSERT_HEAD(&fs->lfs_reshash[h], re, res);
228 splx(s);
229 mutex_exit(&lfs_lock);
230 return r;
231 }
232 }
233 DLOG((DLOG_MALLOC, "sleeping on %s (%d)\n",
234 lfs_res_names[type], lfs_res_qty[type]));
235 mtsleep(&fs->lfs_resblk, PVM, "lfs_malloc", 0,
236 &lfs_lock);
237 DLOG((DLOG_MALLOC, "done sleeping on %s\n",
238 lfs_res_names[type]));
239 }
240 /* NOTREACHED */
241 mutex_exit(&lfs_lock);
242 return r;
243 }
244
245 void
246 lfs_free(struct lfs *fs, void *p, int type)
247 {
248 int s;
249 unsigned int h;
250 res_t *re;
251 #ifdef DEBUG
252 int i;
253 #endif
254
255 ASSERT_MAYBE_SEGLOCK(fs);
256 h = lfs_mhash(p);
257 mutex_enter(&lfs_lock);
258 s = splbio();
259 LIST_FOREACH(re, &fs->lfs_reshash[h], res) {
260 if (re->p == p) {
261 KASSERT(re->inuse == 1);
262 LIST_REMOVE(re, res);
263 re->inuse = 0;
264 wakeup(&fs->lfs_resblk);
265 splx(s);
266 mutex_exit(&lfs_lock);
267 return;
268 }
269 }
270 #ifdef DEBUG
271 for (i = 0; i < LFS_N_TOTAL; i++) {
272 if (fs->lfs_resblk[i].p == p)
273 panic("lfs_free: inconsistent reserved block");
274 }
275 #endif
276 splx(s);
277 mutex_exit(&lfs_lock);
278
279 /*
280 * If we didn't find it, free it.
281 */
282 free(p, M_SEGMENT);
283 }
284
285 /*
286 * lfs_seglock --
287 * Single thread the segment writer.
288 */
289 int
290 lfs_seglock(struct lfs *fs, unsigned long flags)
291 {
292 struct segment *sp;
293
294 mutex_enter(&lfs_lock);
295 if (fs->lfs_seglock) {
296 if (fs->lfs_lockpid == curproc->p_pid &&
297 fs->lfs_locklwp == curlwp->l_lid) {
298 ++fs->lfs_seglock;
299 fs->lfs_sp->seg_flags |= flags;
300 mutex_exit(&lfs_lock);
301 return 0;
302 } else if (flags & SEGM_PAGEDAEMON) {
303 mutex_exit(&lfs_lock);
304 return EWOULDBLOCK;
305 } else {
306 while (fs->lfs_seglock) {
307 (void)mtsleep(&fs->lfs_seglock, PRIBIO + 1,
308 "lfs_seglock", 0, &lfs_lock);
309 }
310 }
311 }
312
313 fs->lfs_seglock = 1;
314 fs->lfs_lockpid = curproc->p_pid;
315 fs->lfs_locklwp = curlwp->l_lid;
316 mutex_exit(&lfs_lock);
317 fs->lfs_cleanind = 0;
318
319 #ifdef DEBUG
320 LFS_ENTER_LOG("seglock", __FILE__, __LINE__, 0, flags, curproc->p_pid);
321 #endif
322 /* Drain fragment size changes out */
323 rw_enter(&fs->lfs_fraglock, RW_WRITER);
324
325 sp = fs->lfs_sp = pool_get(&fs->lfs_segpool, PR_WAITOK);
326 sp->bpp = pool_get(&fs->lfs_bpppool, PR_WAITOK);
327 sp->seg_flags = flags;
328 sp->vp = NULL;
329 sp->seg_iocount = 0;
330 (void) lfs_initseg(fs);
331
332 /*
333 * Keep a cumulative count of the outstanding I/O operations. If the
334 * disk drive catches up with us it could go to zero before we finish,
335 * so we artificially increment it by one until we've scheduled all of
336 * the writes we intend to do.
337 */
338 mutex_enter(&lfs_lock);
339 ++fs->lfs_iocount;
340 fs->lfs_startseg = lfs_sb_getcurseg(fs);
341 mutex_exit(&lfs_lock);
342 return 0;
343 }
344
345 static void lfs_unmark_dirop(struct lfs *);
346
347 static void
348 lfs_unmark_dirop(struct lfs *fs)
349 {
350 struct inode *ip, *nip;
351 struct vnode *vp;
352 int doit;
353
354 ASSERT_NO_SEGLOCK(fs);
355 mutex_enter(&lfs_lock);
356 doit = !(fs->lfs_flags & LFS_UNDIROP);
357 if (doit)
358 fs->lfs_flags |= LFS_UNDIROP;
359 if (!doit) {
360 mutex_exit(&lfs_lock);
361 return;
362 }
363
364 for (ip = TAILQ_FIRST(&fs->lfs_dchainhd); ip != NULL; ip = nip) {
365 nip = TAILQ_NEXT(ip, i_lfs_dchain);
366 vp = ITOV(ip);
367 if ((ip->i_flag & (IN_ADIROP | IN_CDIROP)) == IN_CDIROP) {
368 --lfs_dirvcount;
369 --fs->lfs_dirvcount;
370 vp->v_uflag &= ~VU_DIROP;
371 TAILQ_REMOVE(&fs->lfs_dchainhd, ip, i_lfs_dchain);
372 wakeup(&lfs_dirvcount);
373 fs->lfs_unlockvp = vp;
374 mutex_exit(&lfs_lock);
375 vrele(vp);
376 mutex_enter(&lfs_lock);
377 fs->lfs_unlockvp = NULL;
378 ip->i_flag &= ~IN_CDIROP;
379 }
380 }
381
382 fs->lfs_flags &= ~LFS_UNDIROP;
383 wakeup(&fs->lfs_flags);
384 mutex_exit(&lfs_lock);
385 }
386
387 static void
388 lfs_auto_segclean(struct lfs *fs)
389 {
390 int i, error, s, waited;
391
392 ASSERT_SEGLOCK(fs);
393 /*
394 * Now that we've swapped lfs_activesb, but while we still
395 * hold the segment lock, run through the segment list marking
396 * the empty ones clean.
397 * XXX - do we really need to do them all at once?
398 */
399 waited = 0;
400 for (i = 0; i < lfs_sb_getnseg(fs); i++) {
401 if ((fs->lfs_suflags[0][i] &
402 (SEGUSE_ACTIVE | SEGUSE_DIRTY | SEGUSE_EMPTY)) ==
403 (SEGUSE_DIRTY | SEGUSE_EMPTY) &&
404 (fs->lfs_suflags[1][i] &
405 (SEGUSE_ACTIVE | SEGUSE_DIRTY | SEGUSE_EMPTY)) ==
406 (SEGUSE_DIRTY | SEGUSE_EMPTY)) {
407
408 /* Make sure the sb is written before we clean */
409 mutex_enter(&lfs_lock);
410 s = splbio();
411 while (waited == 0 && fs->lfs_sbactive)
412 mtsleep(&fs->lfs_sbactive, PRIBIO+1, "lfs asb",
413 0, &lfs_lock);
414 splx(s);
415 mutex_exit(&lfs_lock);
416 waited = 1;
417
418 if ((error = lfs_do_segclean(fs, i)) != 0) {
419 DLOG((DLOG_CLEAN, "lfs_auto_segclean: lfs_do_segclean returned %d for seg %d\n", error, i));
420 }
421 }
422 fs->lfs_suflags[1 - fs->lfs_activesb][i] =
423 fs->lfs_suflags[fs->lfs_activesb][i];
424 }
425 }
426
427 /*
428 * lfs_segunlock --
429 * Single thread the segment writer.
430 */
431 void
432 lfs_segunlock(struct lfs *fs)
433 {
434 struct segment *sp;
435 unsigned long sync, ckp;
436 struct buf *bp;
437 int do_unmark_dirop = 0;
438
439 sp = fs->lfs_sp;
440
441 mutex_enter(&lfs_lock);
442 KASSERT(LFS_SEGLOCK_HELD(fs));
443 if (fs->lfs_seglock == 1) {
444 if ((sp->seg_flags & (SEGM_PROT | SEGM_CLEAN)) == 0)
445 do_unmark_dirop = 1;
446 mutex_exit(&lfs_lock);
447 sync = sp->seg_flags & SEGM_SYNC;
448 ckp = sp->seg_flags & SEGM_CKP;
449
450 /* We should have a segment summary, and nothing else */
451 KASSERT(sp->cbpp == sp->bpp + 1);
452
453 /* Free allocated segment summary */
454 lfs_sb_suboffset(fs, lfs_btofsb(fs, lfs_sb_getsumsize(fs)));
455 bp = *sp->bpp;
456 lfs_freebuf(fs, bp);
457
458 pool_put(&fs->lfs_bpppool, sp->bpp);
459 sp->bpp = NULL;
460
461 /*
462 * If we're not sync, we're done with sp, get rid of it.
463 * Otherwise, we keep a local copy around but free
464 * fs->lfs_sp so another process can use it (we have to
465 * wait but they don't have to wait for us).
466 */
467 if (!sync)
468 pool_put(&fs->lfs_segpool, sp);
469 fs->lfs_sp = NULL;
470
471 /*
472 * If the I/O count is non-zero, sleep until it reaches zero.
473 * At the moment, the user's process hangs around so we can
474 * sleep.
475 */
476 mutex_enter(&lfs_lock);
477 if (--fs->lfs_iocount == 0) {
478 LFS_DEBUG_COUNTLOCKED("lfs_segunlock");
479 }
480 if (fs->lfs_iocount <= 1)
481 wakeup(&fs->lfs_iocount);
482 mutex_exit(&lfs_lock);
483 /*
484 * If we're not checkpointing, we don't have to block
485 * other processes to wait for a synchronous write
486 * to complete.
487 */
488 if (!ckp) {
489 #ifdef DEBUG
490 LFS_ENTER_LOG("segunlock_std", __FILE__, __LINE__, 0, 0, curproc->p_pid);
491 #endif
492 mutex_enter(&lfs_lock);
493 --fs->lfs_seglock;
494 fs->lfs_lockpid = 0;
495 fs->lfs_locklwp = 0;
496 mutex_exit(&lfs_lock);
497 wakeup(&fs->lfs_seglock);
498 }
499 /*
500 * We let checkpoints happen asynchronously. That means
501 * that during recovery, we have to roll forward between
502 * the two segments described by the first and second
503 * superblocks to make sure that the checkpoint described
504 * by a superblock completed.
505 */
506 mutex_enter(&lfs_lock);
507 while (ckp && sync && fs->lfs_iocount) {
508 (void)mtsleep(&fs->lfs_iocount, PRIBIO + 1,
509 "lfs_iocount", 0, &lfs_lock);
510 DLOG((DLOG_SEG, "sleeping on iocount %x == %d\n", fs, fs->lfs_iocount));
511 }
512 while (sync && sp->seg_iocount) {
513 (void)mtsleep(&sp->seg_iocount, PRIBIO + 1,
514 "seg_iocount", 0, &lfs_lock);
515 DLOG((DLOG_SEG, "sleeping on iocount %x == %d\n", sp, sp->seg_iocount));
516 }
517 mutex_exit(&lfs_lock);
518 if (sync)
519 pool_put(&fs->lfs_segpool, sp);
520
521 if (ckp) {
522 fs->lfs_nactive = 0;
523 /* If we *know* everything's on disk, write both sbs */
524 /* XXX should wait for this one */
525 if (sync)
526 lfs_writesuper(fs, lfs_sb_getsboff(fs, fs->lfs_activesb));
527 lfs_writesuper(fs, lfs_sb_getsboff(fs, 1 - fs->lfs_activesb));
528 if (!(fs->lfs_ivnode->v_mount->mnt_iflag & IMNT_UNMOUNT)) {
529 lfs_auto_segclean(fs);
530 /* If sync, we can clean the remainder too */
531 if (sync)
532 lfs_auto_segclean(fs);
533 }
534 fs->lfs_activesb = 1 - fs->lfs_activesb;
535 #ifdef DEBUG
536 LFS_ENTER_LOG("segunlock_ckp", __FILE__, __LINE__, 0, 0, curproc->p_pid);
537 #endif
538 mutex_enter(&lfs_lock);
539 --fs->lfs_seglock;
540 fs->lfs_lockpid = 0;
541 fs->lfs_locklwp = 0;
542 mutex_exit(&lfs_lock);
543 wakeup(&fs->lfs_seglock);
544 }
545 /* Reenable fragment size changes */
546 rw_exit(&fs->lfs_fraglock);
547 if (do_unmark_dirop)
548 lfs_unmark_dirop(fs);
549 } else if (fs->lfs_seglock == 0) {
550 mutex_exit(&lfs_lock);
551 panic ("Seglock not held");
552 } else {
553 --fs->lfs_seglock;
554 mutex_exit(&lfs_lock);
555 }
556 }
557
558 /*
559 * Drain dirops and start writer.
560 *
561 * No simple_locks are held when we enter and none are held when we return.
562 */
563 int
564 lfs_writer_enter(struct lfs *fs, const char *wmesg)
565 {
566 int error = 0;
567
568 ASSERT_MAYBE_SEGLOCK(fs);
569 mutex_enter(&lfs_lock);
570
571 /* disallow dirops during flush */
572 fs->lfs_writer++;
573
574 while (fs->lfs_dirops > 0) {
575 ++fs->lfs_diropwait;
576 error = mtsleep(&fs->lfs_writer, PRIBIO+1, wmesg, 0,
577 &lfs_lock);
578 --fs->lfs_diropwait;
579 }
580
581 if (error)
582 fs->lfs_writer--;
583
584 mutex_exit(&lfs_lock);
585
586 return error;
587 }
588
589 void
590 lfs_writer_leave(struct lfs *fs)
591 {
592 bool dowakeup;
593
594 ASSERT_MAYBE_SEGLOCK(fs);
595 mutex_enter(&lfs_lock);
596 dowakeup = !(--fs->lfs_writer);
597 mutex_exit(&lfs_lock);
598 if (dowakeup)
599 wakeup(&fs->lfs_dirops);
600 }
601
602 /*
603 * Unlock, wait for the cleaner, then relock to where we were before.
604 * To be used only at a fairly high level, to address a paucity of free
605 * segments propagated back from lfs_gop_write().
606 */
607 void
608 lfs_segunlock_relock(struct lfs *fs)
609 {
610 int n = fs->lfs_seglock;
611 u_int16_t seg_flags;
612 CLEANERINFO *cip;
613 struct buf *bp;
614
615 if (n == 0)
616 return;
617
618 /* Write anything we've already gathered to disk */
619 lfs_writeseg(fs, fs->lfs_sp);
620
621 /* Tell cleaner */
622 LFS_CLEANERINFO(cip, fs, bp);
623 cip->flags |= LFS_CLEANER_MUST_CLEAN;
624 LFS_SYNC_CLEANERINFO(cip, fs, bp, 1);
625
626 /* Save segment flags for later */
627 seg_flags = fs->lfs_sp->seg_flags;
628
629 fs->lfs_sp->seg_flags |= SEGM_PROT; /* Don't unmark dirop nodes */
630 while(fs->lfs_seglock)
631 lfs_segunlock(fs);
632
633 /* Wait for the cleaner */
634 lfs_wakeup_cleaner(fs);
635 mutex_enter(&lfs_lock);
636 while (LFS_STARVED_FOR_SEGS(fs))
637 mtsleep(&fs->lfs_availsleep, PRIBIO, "relock", 0,
638 &lfs_lock);
639 mutex_exit(&lfs_lock);
640
641 /* Put the segment lock back the way it was. */
642 while(n--)
643 lfs_seglock(fs, seg_flags);
644
645 /* Cleaner can relax now */
646 LFS_CLEANERINFO(cip, fs, bp);
647 cip->flags &= ~LFS_CLEANER_MUST_CLEAN;
648 LFS_SYNC_CLEANERINFO(cip, fs, bp, 1);
649
650 return;
651 }
652
653 /*
654 * Wake up the cleaner, provided that nowrap is not set.
655 */
656 void
657 lfs_wakeup_cleaner(struct lfs *fs)
658 {
659 if (fs->lfs_nowrap > 0)
660 return;
661
662 wakeup(&fs->lfs_nextsegsleep);
663 wakeup(&lfs_allclean_wakeup);
664 }
665