lfs_subr.c revision 1.72 1 /* $NetBSD: lfs_subr.c,v 1.72 2008/01/02 11:49:12 ad 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 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the NetBSD
21 * Foundation, Inc. and its contributors.
22 * 4. Neither the name of The NetBSD Foundation nor the names of its
23 * contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
37 */
38 /*
39 * Copyright (c) 1991, 1993
40 * The Regents of the University of California. All rights reserved.
41 *
42 * Redistribution and use in source and binary forms, with or without
43 * modification, are permitted provided that the following conditions
44 * are met:
45 * 1. Redistributions of source code must retain the above copyright
46 * notice, this list of conditions and the following disclaimer.
47 * 2. Redistributions in binary form must reproduce the above copyright
48 * notice, this list of conditions and the following disclaimer in the
49 * documentation and/or other materials provided with the distribution.
50 * 3. Neither the name of the University nor the names of its contributors
51 * may be used to endorse or promote products derived from this software
52 * without specific prior written permission.
53 *
54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64 * SUCH DAMAGE.
65 *
66 * @(#)lfs_subr.c 8.4 (Berkeley) 5/8/95
67 */
68
69 #include <sys/cdefs.h>
70 __KERNEL_RCSID(0, "$NetBSD: lfs_subr.c,v 1.72 2008/01/02 11:49:12 ad Exp $");
71
72 #include <sys/param.h>
73 #include <sys/systm.h>
74 #include <sys/namei.h>
75 #include <sys/vnode.h>
76 #include <sys/buf.h>
77 #include <sys/mount.h>
78 #include <sys/malloc.h>
79 #include <sys/proc.h>
80 #include <sys/kauth.h>
81
82 #include <ufs/ufs/inode.h>
83 #include <ufs/lfs/lfs.h>
84 #include <ufs/lfs/lfs_extern.h>
85
86 #include <uvm/uvm.h>
87
88 #ifdef DEBUG
89 const char *lfs_res_names[LFS_NB_COUNT] = {
90 "summary",
91 "superblock",
92 "file block",
93 "cluster",
94 "clean",
95 "blkiov",
96 };
97 #endif
98
99 int lfs_res_qty[LFS_NB_COUNT] = {
100 LFS_N_SUMMARIES,
101 LFS_N_SBLOCKS,
102 LFS_N_IBLOCKS,
103 LFS_N_CLUSTERS,
104 LFS_N_CLEAN,
105 LFS_N_BLKIOV,
106 };
107
108 void
109 lfs_setup_resblks(struct lfs *fs)
110 {
111 int i, j;
112 int maxbpp;
113
114 ASSERT_NO_SEGLOCK(fs);
115 fs->lfs_resblk = (res_t *)malloc(LFS_N_TOTAL * sizeof(res_t), M_SEGMENT,
116 M_WAITOK);
117 for (i = 0; i < LFS_N_TOTAL; i++) {
118 fs->lfs_resblk[i].inuse = 0;
119 fs->lfs_resblk[i].p = NULL;
120 }
121 for (i = 0; i < LFS_RESHASH_WIDTH; i++)
122 LIST_INIT(fs->lfs_reshash + i);
123
124 /*
125 * These types of allocations can be larger than a page,
126 * so we can't use the pool subsystem for them.
127 */
128 for (i = 0, j = 0; j < LFS_N_SUMMARIES; j++, i++)
129 fs->lfs_resblk[i].size = fs->lfs_sumsize;
130 for (j = 0; j < LFS_N_SBLOCKS; j++, i++)
131 fs->lfs_resblk[i].size = LFS_SBPAD;
132 for (j = 0; j < LFS_N_IBLOCKS; j++, i++)
133 fs->lfs_resblk[i].size = fs->lfs_bsize;
134 for (j = 0; j < LFS_N_CLUSTERS; j++, i++)
135 fs->lfs_resblk[i].size = MAXPHYS;
136 for (j = 0; j < LFS_N_CLEAN; j++, i++)
137 fs->lfs_resblk[i].size = MAXPHYS;
138 for (j = 0; j < LFS_N_BLKIOV; j++, i++)
139 fs->lfs_resblk[i].size = LFS_MARKV_MAXBLKCNT * sizeof(BLOCK_INFO);
140
141 for (i = 0; i < LFS_N_TOTAL; i++) {
142 fs->lfs_resblk[i].p = malloc(fs->lfs_resblk[i].size,
143 M_SEGMENT, M_WAITOK);
144 }
145
146 /*
147 * Initialize pools for small types (XXX is BPP small?)
148 */
149 pool_init(&fs->lfs_clpool, sizeof(struct lfs_cluster), 0, 0, 0,
150 "lfsclpl", &pool_allocator_nointr, IPL_NONE);
151 pool_init(&fs->lfs_segpool, sizeof(struct segment), 0, 0, 0,
152 "lfssegpool", &pool_allocator_nointr, IPL_NONE);
153 maxbpp = ((fs->lfs_sumsize - SEGSUM_SIZE(fs)) / sizeof(int32_t) + 2);
154 maxbpp = MIN(maxbpp, segsize(fs) / fs->lfs_fsize + 2);
155 pool_init(&fs->lfs_bpppool, maxbpp * sizeof(struct buf *), 0, 0, 0,
156 "lfsbpppl", &pool_allocator_nointr, IPL_NONE);
157 }
158
159 void
160 lfs_free_resblks(struct lfs *fs)
161 {
162 int i;
163
164 pool_destroy(&fs->lfs_bpppool);
165 pool_destroy(&fs->lfs_segpool);
166 pool_destroy(&fs->lfs_clpool);
167
168 mutex_enter(&lfs_lock);
169 for (i = 0; i < LFS_N_TOTAL; i++) {
170 while (fs->lfs_resblk[i].inuse)
171 mtsleep(&fs->lfs_resblk, PRIBIO + 1, "lfs_free", 0,
172 &lfs_lock);
173 if (fs->lfs_resblk[i].p != NULL)
174 free(fs->lfs_resblk[i].p, M_SEGMENT);
175 }
176 free(fs->lfs_resblk, M_SEGMENT);
177 mutex_exit(&lfs_lock);
178 }
179
180 static unsigned int
181 lfs_mhash(void *vp)
182 {
183 return (unsigned int)(((unsigned long)vp) >> 2) % LFS_RESHASH_WIDTH;
184 }
185
186 /*
187 * Return memory of the given size for the given purpose, or use one of a
188 * number of spare last-resort buffers, if malloc returns NULL.
189 */
190 void *
191 lfs_malloc(struct lfs *fs, size_t size, int type)
192 {
193 struct lfs_res_blk *re;
194 void *r;
195 int i, s, start;
196 unsigned int h;
197
198 ASSERT_MAYBE_SEGLOCK(fs);
199 r = NULL;
200
201 /* If no mem allocated for this type, it just waits */
202 if (lfs_res_qty[type] == 0) {
203 r = malloc(size, M_SEGMENT, M_WAITOK);
204 return r;
205 }
206
207 /* Otherwise try a quick malloc, and if it works, great */
208 if ((r = malloc(size, M_SEGMENT, M_NOWAIT)) != NULL) {
209 return r;
210 }
211
212 /*
213 * If malloc returned NULL, we are forced to use one of our
214 * reserve blocks. We have on hand at least one summary block,
215 * at least one cluster block, at least one superblock,
216 * and several indirect blocks.
217 */
218
219 mutex_enter(&lfs_lock);
220 /* skip over blocks of other types */
221 for (i = 0, start = 0; i < type; i++)
222 start += lfs_res_qty[i];
223 while (r == NULL) {
224 for (i = 0; i < lfs_res_qty[type]; i++) {
225 if (fs->lfs_resblk[start + i].inuse == 0) {
226 re = fs->lfs_resblk + start + i;
227 re->inuse = 1;
228 r = re->p;
229 KASSERT(re->size >= size);
230 h = lfs_mhash(r);
231 s = splbio();
232 LIST_INSERT_HEAD(&fs->lfs_reshash[h], re, res);
233 splx(s);
234 mutex_exit(&lfs_lock);
235 return r;
236 }
237 }
238 DLOG((DLOG_MALLOC, "sleeping on %s (%d)\n",
239 lfs_res_names[type], lfs_res_qty[type]));
240 mtsleep(&fs->lfs_resblk, PVM, "lfs_malloc", 0,
241 &lfs_lock);
242 DLOG((DLOG_MALLOC, "done sleeping on %s\n",
243 lfs_res_names[type]));
244 }
245 /* NOTREACHED */
246 mutex_exit(&lfs_lock);
247 return r;
248 }
249
250 void
251 lfs_free(struct lfs *fs, void *p, int type)
252 {
253 int s;
254 unsigned int h;
255 res_t *re;
256 #ifdef DEBUG
257 int i;
258 #endif
259
260 ASSERT_MAYBE_SEGLOCK(fs);
261 h = lfs_mhash(p);
262 mutex_enter(&lfs_lock);
263 s = splbio();
264 LIST_FOREACH(re, &fs->lfs_reshash[h], res) {
265 if (re->p == p) {
266 KASSERT(re->inuse == 1);
267 LIST_REMOVE(re, res);
268 re->inuse = 0;
269 wakeup(&fs->lfs_resblk);
270 splx(s);
271 mutex_exit(&lfs_lock);
272 return;
273 }
274 }
275 #ifdef DEBUG
276 for (i = 0; i < LFS_N_TOTAL; i++) {
277 if (fs->lfs_resblk[i].p == p)
278 panic("lfs_free: inconsistent reserved block");
279 }
280 #endif
281 splx(s);
282 mutex_exit(&lfs_lock);
283
284 /*
285 * If we didn't find it, free it.
286 */
287 free(p, M_SEGMENT);
288 }
289
290 /*
291 * lfs_seglock --
292 * Single thread the segment writer.
293 */
294 int
295 lfs_seglock(struct lfs *fs, unsigned long flags)
296 {
297 struct segment *sp;
298
299 mutex_enter(&lfs_lock);
300 if (fs->lfs_seglock) {
301 if (fs->lfs_lockpid == curproc->p_pid &&
302 fs->lfs_locklwp == curlwp->l_lid) {
303 mutex_exit(&lfs_lock);
304 ++fs->lfs_seglock;
305 fs->lfs_sp->seg_flags |= flags;
306 return 0;
307 } else if (flags & SEGM_PAGEDAEMON) {
308 mutex_exit(&lfs_lock);
309 return EWOULDBLOCK;
310 } else {
311 while (fs->lfs_seglock) {
312 (void)mtsleep(&fs->lfs_seglock, PRIBIO + 1,
313 "lfs_seglock", 0, &lfs_lock);
314 }
315 }
316 }
317
318 fs->lfs_seglock = 1;
319 fs->lfs_lockpid = curproc->p_pid;
320 fs->lfs_locklwp = curlwp->l_lid;
321 mutex_exit(&lfs_lock);
322 fs->lfs_cleanind = 0;
323
324 #ifdef DEBUG
325 LFS_ENTER_LOG("seglock", __FILE__, __LINE__, 0, flags, curproc->p_pid);
326 #endif
327 /* Drain fragment size changes out */
328 rw_enter(&fs->lfs_fraglock, RW_WRITER);
329
330 sp = fs->lfs_sp = pool_get(&fs->lfs_segpool, PR_WAITOK);
331 sp->bpp = pool_get(&fs->lfs_bpppool, PR_WAITOK);
332 sp->seg_flags = flags;
333 sp->vp = NULL;
334 sp->seg_iocount = 0;
335 (void) lfs_initseg(fs);
336
337 /*
338 * Keep a cumulative count of the outstanding I/O operations. If the
339 * disk drive catches up with us it could go to zero before we finish,
340 * so we artificially increment it by one until we've scheduled all of
341 * the writes we intend to do.
342 */
343 mutex_enter(&lfs_lock);
344 ++fs->lfs_iocount;
345 mutex_exit(&lfs_lock);
346 return 0;
347 }
348
349 static void lfs_unmark_dirop(struct lfs *);
350
351 static void
352 lfs_unmark_dirop(struct lfs *fs)
353 {
354 struct inode *ip, *nip;
355 struct vnode *vp;
356 int doit;
357
358 ASSERT_NO_SEGLOCK(fs);
359 mutex_enter(&lfs_lock);
360 doit = !(fs->lfs_flags & LFS_UNDIROP);
361 if (doit)
362 fs->lfs_flags |= LFS_UNDIROP;
363 if (!doit) {
364 mutex_exit(&lfs_lock);
365 return;
366 }
367
368 for (ip = TAILQ_FIRST(&fs->lfs_dchainhd); ip != NULL; ip = nip) {
369 nip = TAILQ_NEXT(ip, i_lfs_dchain);
370 vp = ITOV(ip);
371 if (VOP_ISLOCKED(vp) == LK_EXCLOTHER)
372 continue;
373 if ((VTOI(vp)->i_flag & (IN_ADIROP | IN_ALLMOD)) == 0) {
374 --lfs_dirvcount;
375 --fs->lfs_dirvcount;
376 vp->v_uflag &= ~VU_DIROP;
377 TAILQ_REMOVE(&fs->lfs_dchainhd, ip, i_lfs_dchain);
378 wakeup(&lfs_dirvcount);
379 fs->lfs_unlockvp = vp;
380 mutex_exit(&lfs_lock);
381 vrele(vp);
382 mutex_enter(&lfs_lock);
383 fs->lfs_unlockvp = NULL;
384 }
385 }
386
387 fs->lfs_flags &= ~LFS_UNDIROP;
388 wakeup(&fs->lfs_flags);
389 mutex_exit(&lfs_lock);
390 }
391
392 static void
393 lfs_auto_segclean(struct lfs *fs)
394 {
395 int i, error, s, waited;
396
397 ASSERT_SEGLOCK(fs);
398 /*
399 * Now that we've swapped lfs_activesb, but while we still
400 * hold the segment lock, run through the segment list marking
401 * the empty ones clean.
402 * XXX - do we really need to do them all at once?
403 */
404 waited = 0;
405 for (i = 0; i < fs->lfs_nseg; i++) {
406 if ((fs->lfs_suflags[0][i] &
407 (SEGUSE_ACTIVE | SEGUSE_DIRTY | SEGUSE_EMPTY)) ==
408 (SEGUSE_DIRTY | SEGUSE_EMPTY) &&
409 (fs->lfs_suflags[1][i] &
410 (SEGUSE_ACTIVE | SEGUSE_DIRTY | SEGUSE_EMPTY)) ==
411 (SEGUSE_DIRTY | SEGUSE_EMPTY)) {
412
413 /* Make sure the sb is written before we clean */
414 mutex_enter(&lfs_lock);
415 s = splbio();
416 while (waited == 0 && fs->lfs_sbactive)
417 mtsleep(&fs->lfs_sbactive, PRIBIO+1, "lfs asb",
418 0, &lfs_lock);
419 splx(s);
420 mutex_exit(&lfs_lock);
421 waited = 1;
422
423 if ((error = lfs_do_segclean(fs, i)) != 0) {
424 DLOG((DLOG_CLEAN, "lfs_auto_segclean: lfs_do_segclean returned %d for seg %d\n", error, i));
425 }
426 }
427 fs->lfs_suflags[1 - fs->lfs_activesb][i] =
428 fs->lfs_suflags[fs->lfs_activesb][i];
429 }
430 }
431
432 /*
433 * lfs_segunlock --
434 * Single thread the segment writer.
435 */
436 void
437 lfs_segunlock(struct lfs *fs)
438 {
439 struct segment *sp;
440 unsigned long sync, ckp;
441 struct buf *bp;
442 int do_unmark_dirop = 0;
443
444 sp = fs->lfs_sp;
445
446 mutex_enter(&lfs_lock);
447 KASSERT(LFS_SEGLOCK_HELD(fs));
448 if (fs->lfs_seglock == 1) {
449 if ((sp->seg_flags & (SEGM_PROT | SEGM_CLEAN)) == 0 &&
450 LFS_STARVED_FOR_SEGS(fs) == 0)
451 do_unmark_dirop = 1;
452 mutex_exit(&lfs_lock);
453 sync = sp->seg_flags & SEGM_SYNC;
454 ckp = sp->seg_flags & SEGM_CKP;
455
456 /* We should have a segment summary, and nothing else */
457 KASSERT(sp->cbpp == sp->bpp + 1);
458
459 /* Free allocated segment summary */
460 fs->lfs_offset -= btofsb(fs, fs->lfs_sumsize);
461 bp = *sp->bpp;
462 lfs_freebuf(fs, bp);
463
464 pool_put(&fs->lfs_bpppool, sp->bpp);
465 sp->bpp = NULL;
466
467 /*
468 * If we're not sync, we're done with sp, get rid of it.
469 * Otherwise, we keep a local copy around but free
470 * fs->lfs_sp so another process can use it (we have to
471 * wait but they don't have to wait for us).
472 */
473 if (!sync)
474 pool_put(&fs->lfs_segpool, sp);
475 fs->lfs_sp = NULL;
476
477 /*
478 * If the I/O count is non-zero, sleep until it reaches zero.
479 * At the moment, the user's process hangs around so we can
480 * sleep.
481 */
482 mutex_enter(&lfs_lock);
483 if (--fs->lfs_iocount == 0) {
484 LFS_DEBUG_COUNTLOCKED("lfs_segunlock");
485 }
486 if (fs->lfs_iocount <= 1)
487 wakeup(&fs->lfs_iocount);
488 mutex_exit(&lfs_lock);
489 /*
490 * If we're not checkpointing, we don't have to block
491 * other processes to wait for a synchronous write
492 * to complete.
493 */
494 if (!ckp) {
495 #ifdef DEBUG
496 LFS_ENTER_LOG("segunlock_std", __FILE__, __LINE__, 0, 0, curproc->p_pid);
497 #endif
498 mutex_enter(&lfs_lock);
499 --fs->lfs_seglock;
500 fs->lfs_lockpid = 0;
501 fs->lfs_locklwp = 0;
502 mutex_exit(&lfs_lock);
503 wakeup(&fs->lfs_seglock);
504 }
505 /*
506 * We let checkpoints happen asynchronously. That means
507 * that during recovery, we have to roll forward between
508 * the two segments described by the first and second
509 * superblocks to make sure that the checkpoint described
510 * by a superblock completed.
511 */
512 mutex_enter(&lfs_lock);
513 while (ckp && sync && fs->lfs_iocount)
514 (void)mtsleep(&fs->lfs_iocount, PRIBIO + 1,
515 "lfs_iocount", 0, &lfs_lock);
516 while (sync && sp->seg_iocount) {
517 (void)mtsleep(&sp->seg_iocount, PRIBIO + 1,
518 "seg_iocount", 0, &lfs_lock);
519 DLOG((DLOG_SEG, "sleeping on iocount %x == %d\n", sp, sp->seg_iocount));
520 }
521 mutex_exit(&lfs_lock);
522 if (sync)
523 pool_put(&fs->lfs_segpool, sp);
524
525 if (ckp) {
526 fs->lfs_nactive = 0;
527 /* If we *know* everything's on disk, write both sbs */
528 /* XXX should wait for this one */
529 if (sync)
530 lfs_writesuper(fs, fs->lfs_sboffs[fs->lfs_activesb]);
531 lfs_writesuper(fs, fs->lfs_sboffs[1 - fs->lfs_activesb]);
532 if (!(fs->lfs_ivnode->v_mount->mnt_iflag & IMNT_UNMOUNT)) {
533 lfs_auto_segclean(fs);
534 /* If sync, we can clean the remainder too */
535 if (sync)
536 lfs_auto_segclean(fs);
537 }
538 fs->lfs_activesb = 1 - fs->lfs_activesb;
539 #ifdef DEBUG
540 LFS_ENTER_LOG("segunlock_ckp", __FILE__, __LINE__, 0, 0, curproc->p_pid);
541 #endif
542 mutex_enter(&lfs_lock);
543 --fs->lfs_seglock;
544 fs->lfs_lockpid = 0;
545 fs->lfs_locklwp = 0;
546 mutex_exit(&lfs_lock);
547 wakeup(&fs->lfs_seglock);
548 }
549 /* Reenable fragment size changes */
550 rw_exit(&fs->lfs_fraglock);
551 if (do_unmark_dirop)
552 lfs_unmark_dirop(fs);
553 } else if (fs->lfs_seglock == 0) {
554 mutex_exit(&lfs_lock);
555 panic ("Seglock not held");
556 } else {
557 --fs->lfs_seglock;
558 mutex_exit(&lfs_lock);
559 }
560 }
561
562 /*
563 * Drain dirops and start writer.
564 *
565 * No simple_locks are held when we enter and none are held when we return.
566 */
567 int
568 lfs_writer_enter(struct lfs *fs, const char *wmesg)
569 {
570 int error = 0;
571
572 ASSERT_MAYBE_SEGLOCK(fs);
573 mutex_enter(&lfs_lock);
574
575 /* disallow dirops during flush */
576 fs->lfs_writer++;
577
578 while (fs->lfs_dirops > 0) {
579 ++fs->lfs_diropwait;
580 error = mtsleep(&fs->lfs_writer, PRIBIO+1, wmesg, 0,
581 &lfs_lock);
582 --fs->lfs_diropwait;
583 }
584
585 if (error)
586 fs->lfs_writer--;
587
588 mutex_exit(&lfs_lock);
589
590 return error;
591 }
592
593 void
594 lfs_writer_leave(struct lfs *fs)
595 {
596 bool dowakeup;
597
598 ASSERT_MAYBE_SEGLOCK(fs);
599 mutex_enter(&lfs_lock);
600 dowakeup = !(--fs->lfs_writer);
601 mutex_exit(&lfs_lock);
602 if (dowakeup)
603 wakeup(&fs->lfs_dirops);
604 }
605
606 /*
607 * Unlock, wait for the cleaner, then relock to where we were before.
608 * To be used only at a fairly high level, to address a paucity of free
609 * segments propagated back from lfs_gop_write().
610 */
611 void
612 lfs_segunlock_relock(struct lfs *fs)
613 {
614 int n = fs->lfs_seglock;
615 u_int16_t seg_flags;
616 CLEANERINFO *cip;
617 struct buf *bp;
618
619 if (n == 0)
620 return;
621
622 /* Write anything we've already gathered to disk */
623 lfs_writeseg(fs, fs->lfs_sp);
624
625 /* Tell cleaner */
626 LFS_CLEANERINFO(cip, fs, bp);
627 cip->flags |= LFS_CLEANER_MUST_CLEAN;
628 LFS_SYNC_CLEANERINFO(cip, fs, bp, 1);
629
630 /* Save segment flags for later */
631 seg_flags = fs->lfs_sp->seg_flags;
632
633 fs->lfs_sp->seg_flags |= SEGM_PROT; /* Don't unmark dirop nodes */
634 while(fs->lfs_seglock)
635 lfs_segunlock(fs);
636
637 /* Wait for the cleaner */
638 lfs_wakeup_cleaner(fs);
639 mutex_enter(&lfs_lock);
640 while (LFS_STARVED_FOR_SEGS(fs))
641 mtsleep(&fs->lfs_avail, PRIBIO, "relock", 0,
642 &lfs_lock);
643 mutex_exit(&lfs_lock);
644
645 /* Put the segment lock back the way it was. */
646 while(n--)
647 lfs_seglock(fs, seg_flags);
648
649 /* Cleaner can relax now */
650 LFS_CLEANERINFO(cip, fs, bp);
651 cip->flags &= ~LFS_CLEANER_MUST_CLEAN;
652 LFS_SYNC_CLEANERINFO(cip, fs, bp, 1);
653
654 return;
655 }
656
657 /*
658 * Wake up the cleaner, provided that nowrap is not set.
659 */
660 void
661 lfs_wakeup_cleaner(struct lfs *fs)
662 {
663 if (fs->lfs_nowrap > 0)
664 return;
665
666 wakeup(&fs->lfs_nextseg);
667 wakeup(&lfs_allclean_wakeup);
668 }
669