lfs_subr.c revision 1.80 1 /* $NetBSD: lfs_subr.c,v 1.80 2013/07/28 01:05:52 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 1.80 2013/07/28 01:05:52 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_kernel.h>
78 #include <ufs/lfs/lfs_extern.h>
79
80 #include <uvm/uvm.h>
81
82 #ifdef DEBUG
83 const char *lfs_res_names[LFS_NB_COUNT] = {
84 "summary",
85 "superblock",
86 "file block",
87 "cluster",
88 "clean",
89 "blkiov",
90 };
91 #endif
92
93 int lfs_res_qty[LFS_NB_COUNT] = {
94 LFS_N_SUMMARIES,
95 LFS_N_SBLOCKS,
96 LFS_N_IBLOCKS,
97 LFS_N_CLUSTERS,
98 LFS_N_CLEAN,
99 LFS_N_BLKIOV,
100 };
101
102 void
103 lfs_setup_resblks(struct lfs *fs)
104 {
105 int i, j;
106 int maxbpp;
107
108 ASSERT_NO_SEGLOCK(fs);
109 fs->lfs_resblk = (res_t *)malloc(LFS_N_TOTAL * sizeof(res_t), M_SEGMENT,
110 M_WAITOK);
111 for (i = 0; i < LFS_N_TOTAL; i++) {
112 fs->lfs_resblk[i].inuse = 0;
113 fs->lfs_resblk[i].p = NULL;
114 }
115 for (i = 0; i < LFS_RESHASH_WIDTH; i++)
116 LIST_INIT(fs->lfs_reshash + i);
117
118 /*
119 * These types of allocations can be larger than a page,
120 * so we can't use the pool subsystem for them.
121 */
122 for (i = 0, j = 0; j < LFS_N_SUMMARIES; j++, i++)
123 fs->lfs_resblk[i].size = fs->lfs_sumsize;
124 for (j = 0; j < LFS_N_SBLOCKS; j++, i++)
125 fs->lfs_resblk[i].size = LFS_SBPAD;
126 for (j = 0; j < LFS_N_IBLOCKS; j++, i++)
127 fs->lfs_resblk[i].size = fs->lfs_bsize;
128 for (j = 0; j < LFS_N_CLUSTERS; j++, i++)
129 fs->lfs_resblk[i].size = MAXPHYS;
130 for (j = 0; j < LFS_N_CLEAN; j++, i++)
131 fs->lfs_resblk[i].size = MAXPHYS;
132 for (j = 0; j < LFS_N_BLKIOV; j++, i++)
133 fs->lfs_resblk[i].size = LFS_MARKV_MAXBLKCNT * sizeof(BLOCK_INFO);
134
135 for (i = 0; i < LFS_N_TOTAL; i++) {
136 fs->lfs_resblk[i].p = malloc(fs->lfs_resblk[i].size,
137 M_SEGMENT, M_WAITOK);
138 }
139
140 /*
141 * Initialize pools for small types (XXX is BPP small?)
142 */
143 pool_init(&fs->lfs_clpool, sizeof(struct lfs_cluster), 0, 0, 0,
144 "lfsclpl", &pool_allocator_nointr, IPL_NONE);
145 pool_init(&fs->lfs_segpool, sizeof(struct segment), 0, 0, 0,
146 "lfssegpool", &pool_allocator_nointr, IPL_NONE);
147 maxbpp = ((fs->lfs_sumsize - SEGSUM_SIZE(fs)) / sizeof(int32_t) + 2);
148 maxbpp = MIN(maxbpp, lfs_segsize(fs) / fs->lfs_fsize + 2);
149 pool_init(&fs->lfs_bpppool, maxbpp * sizeof(struct buf *), 0, 0, 0,
150 "lfsbpppl", &pool_allocator_nointr, IPL_NONE);
151 }
152
153 void
154 lfs_free_resblks(struct lfs *fs)
155 {
156 int i;
157
158 pool_destroy(&fs->lfs_bpppool);
159 pool_destroy(&fs->lfs_segpool);
160 pool_destroy(&fs->lfs_clpool);
161
162 mutex_enter(&lfs_lock);
163 for (i = 0; i < LFS_N_TOTAL; i++) {
164 while (fs->lfs_resblk[i].inuse)
165 mtsleep(&fs->lfs_resblk, PRIBIO + 1, "lfs_free", 0,
166 &lfs_lock);
167 if (fs->lfs_resblk[i].p != NULL)
168 free(fs->lfs_resblk[i].p, M_SEGMENT);
169 }
170 free(fs->lfs_resblk, M_SEGMENT);
171 mutex_exit(&lfs_lock);
172 }
173
174 static unsigned int
175 lfs_mhash(void *vp)
176 {
177 return (unsigned int)(((unsigned long)vp) >> 2) % LFS_RESHASH_WIDTH;
178 }
179
180 /*
181 * Return memory of the given size for the given purpose, or use one of a
182 * number of spare last-resort buffers, if malloc returns NULL.
183 */
184 void *
185 lfs_malloc(struct lfs *fs, size_t size, int type)
186 {
187 struct lfs_res_blk *re;
188 void *r;
189 int i, s, start;
190 unsigned int h;
191
192 ASSERT_MAYBE_SEGLOCK(fs);
193 r = NULL;
194
195 /* If no mem allocated for this type, it just waits */
196 if (lfs_res_qty[type] == 0) {
197 r = malloc(size, M_SEGMENT, M_WAITOK);
198 return r;
199 }
200
201 /* Otherwise try a quick malloc, and if it works, great */
202 if ((r = malloc(size, M_SEGMENT, M_NOWAIT)) != NULL) {
203 return r;
204 }
205
206 /*
207 * If malloc returned NULL, we are forced to use one of our
208 * reserve blocks. We have on hand at least one summary block,
209 * at least one cluster block, at least one superblock,
210 * and several indirect blocks.
211 */
212
213 mutex_enter(&lfs_lock);
214 /* skip over blocks of other types */
215 for (i = 0, start = 0; i < type; i++)
216 start += lfs_res_qty[i];
217 while (r == NULL) {
218 for (i = 0; i < lfs_res_qty[type]; i++) {
219 if (fs->lfs_resblk[start + i].inuse == 0) {
220 re = fs->lfs_resblk + start + i;
221 re->inuse = 1;
222 r = re->p;
223 KASSERT(re->size >= size);
224 h = lfs_mhash(r);
225 s = splbio();
226 LIST_INSERT_HEAD(&fs->lfs_reshash[h], re, res);
227 splx(s);
228 mutex_exit(&lfs_lock);
229 return r;
230 }
231 }
232 DLOG((DLOG_MALLOC, "sleeping on %s (%d)\n",
233 lfs_res_names[type], lfs_res_qty[type]));
234 mtsleep(&fs->lfs_resblk, PVM, "lfs_malloc", 0,
235 &lfs_lock);
236 DLOG((DLOG_MALLOC, "done sleeping on %s\n",
237 lfs_res_names[type]));
238 }
239 /* NOTREACHED */
240 mutex_exit(&lfs_lock);
241 return r;
242 }
243
244 void
245 lfs_free(struct lfs *fs, void *p, int type)
246 {
247 int s;
248 unsigned int h;
249 res_t *re;
250 #ifdef DEBUG
251 int i;
252 #endif
253
254 ASSERT_MAYBE_SEGLOCK(fs);
255 h = lfs_mhash(p);
256 mutex_enter(&lfs_lock);
257 s = splbio();
258 LIST_FOREACH(re, &fs->lfs_reshash[h], res) {
259 if (re->p == p) {
260 KASSERT(re->inuse == 1);
261 LIST_REMOVE(re, res);
262 re->inuse = 0;
263 wakeup(&fs->lfs_resblk);
264 splx(s);
265 mutex_exit(&lfs_lock);
266 return;
267 }
268 }
269 #ifdef DEBUG
270 for (i = 0; i < LFS_N_TOTAL; i++) {
271 if (fs->lfs_resblk[i].p == p)
272 panic("lfs_free: inconsistent reserved block");
273 }
274 #endif
275 splx(s);
276 mutex_exit(&lfs_lock);
277
278 /*
279 * If we didn't find it, free it.
280 */
281 free(p, M_SEGMENT);
282 }
283
284 /*
285 * lfs_seglock --
286 * Single thread the segment writer.
287 */
288 int
289 lfs_seglock(struct lfs *fs, unsigned long flags)
290 {
291 struct segment *sp;
292
293 mutex_enter(&lfs_lock);
294 if (fs->lfs_seglock) {
295 if (fs->lfs_lockpid == curproc->p_pid &&
296 fs->lfs_locklwp == curlwp->l_lid) {
297 ++fs->lfs_seglock;
298 fs->lfs_sp->seg_flags |= flags;
299 mutex_exit(&lfs_lock);
300 return 0;
301 } else if (flags & SEGM_PAGEDAEMON) {
302 mutex_exit(&lfs_lock);
303 return EWOULDBLOCK;
304 } else {
305 while (fs->lfs_seglock) {
306 (void)mtsleep(&fs->lfs_seglock, PRIBIO + 1,
307 "lfs_seglock", 0, &lfs_lock);
308 }
309 }
310 }
311
312 fs->lfs_seglock = 1;
313 fs->lfs_lockpid = curproc->p_pid;
314 fs->lfs_locklwp = curlwp->l_lid;
315 mutex_exit(&lfs_lock);
316 fs->lfs_cleanind = 0;
317
318 #ifdef DEBUG
319 LFS_ENTER_LOG("seglock", __FILE__, __LINE__, 0, flags, curproc->p_pid);
320 #endif
321 /* Drain fragment size changes out */
322 rw_enter(&fs->lfs_fraglock, RW_WRITER);
323
324 sp = fs->lfs_sp = pool_get(&fs->lfs_segpool, PR_WAITOK);
325 sp->bpp = pool_get(&fs->lfs_bpppool, PR_WAITOK);
326 sp->seg_flags = flags;
327 sp->vp = NULL;
328 sp->seg_iocount = 0;
329 (void) lfs_initseg(fs);
330
331 /*
332 * Keep a cumulative count of the outstanding I/O operations. If the
333 * disk drive catches up with us it could go to zero before we finish,
334 * so we artificially increment it by one until we've scheduled all of
335 * the writes we intend to do.
336 */
337 mutex_enter(&lfs_lock);
338 ++fs->lfs_iocount;
339 fs->lfs_startseg = fs->lfs_curseg;
340 mutex_exit(&lfs_lock);
341 return 0;
342 }
343
344 static void lfs_unmark_dirop(struct lfs *);
345
346 static void
347 lfs_unmark_dirop(struct lfs *fs)
348 {
349 struct inode *ip, *nip;
350 struct vnode *vp;
351 int doit;
352
353 ASSERT_NO_SEGLOCK(fs);
354 mutex_enter(&lfs_lock);
355 doit = !(fs->lfs_flags & LFS_UNDIROP);
356 if (doit)
357 fs->lfs_flags |= LFS_UNDIROP;
358 if (!doit) {
359 mutex_exit(&lfs_lock);
360 return;
361 }
362
363 for (ip = TAILQ_FIRST(&fs->lfs_dchainhd); ip != NULL; ip = nip) {
364 nip = TAILQ_NEXT(ip, i_lfs_dchain);
365 vp = ITOV(ip);
366 if ((ip->i_flag & (IN_ADIROP | IN_CDIROP)) == IN_CDIROP) {
367 --lfs_dirvcount;
368 --fs->lfs_dirvcount;
369 vp->v_uflag &= ~VU_DIROP;
370 TAILQ_REMOVE(&fs->lfs_dchainhd, ip, i_lfs_dchain);
371 wakeup(&lfs_dirvcount);
372 fs->lfs_unlockvp = vp;
373 mutex_exit(&lfs_lock);
374 vrele(vp);
375 mutex_enter(&lfs_lock);
376 fs->lfs_unlockvp = NULL;
377 ip->i_flag &= ~IN_CDIROP;
378 }
379 }
380
381 fs->lfs_flags &= ~LFS_UNDIROP;
382 wakeup(&fs->lfs_flags);
383 mutex_exit(&lfs_lock);
384 }
385
386 static void
387 lfs_auto_segclean(struct lfs *fs)
388 {
389 int i, error, s, waited;
390
391 ASSERT_SEGLOCK(fs);
392 /*
393 * Now that we've swapped lfs_activesb, but while we still
394 * hold the segment lock, run through the segment list marking
395 * the empty ones clean.
396 * XXX - do we really need to do them all at once?
397 */
398 waited = 0;
399 for (i = 0; i < fs->lfs_nseg; i++) {
400 if ((fs->lfs_suflags[0][i] &
401 (SEGUSE_ACTIVE | SEGUSE_DIRTY | SEGUSE_EMPTY)) ==
402 (SEGUSE_DIRTY | SEGUSE_EMPTY) &&
403 (fs->lfs_suflags[1][i] &
404 (SEGUSE_ACTIVE | SEGUSE_DIRTY | SEGUSE_EMPTY)) ==
405 (SEGUSE_DIRTY | SEGUSE_EMPTY)) {
406
407 /* Make sure the sb is written before we clean */
408 mutex_enter(&lfs_lock);
409 s = splbio();
410 while (waited == 0 && fs->lfs_sbactive)
411 mtsleep(&fs->lfs_sbactive, PRIBIO+1, "lfs asb",
412 0, &lfs_lock);
413 splx(s);
414 mutex_exit(&lfs_lock);
415 waited = 1;
416
417 if ((error = lfs_do_segclean(fs, i)) != 0) {
418 DLOG((DLOG_CLEAN, "lfs_auto_segclean: lfs_do_segclean returned %d for seg %d\n", error, i));
419 }
420 }
421 fs->lfs_suflags[1 - fs->lfs_activesb][i] =
422 fs->lfs_suflags[fs->lfs_activesb][i];
423 }
424 }
425
426 /*
427 * lfs_segunlock --
428 * Single thread the segment writer.
429 */
430 void
431 lfs_segunlock(struct lfs *fs)
432 {
433 struct segment *sp;
434 unsigned long sync, ckp;
435 struct buf *bp;
436 int do_unmark_dirop = 0;
437
438 sp = fs->lfs_sp;
439
440 mutex_enter(&lfs_lock);
441 KASSERT(LFS_SEGLOCK_HELD(fs));
442 if (fs->lfs_seglock == 1) {
443 if ((sp->seg_flags & (SEGM_PROT | SEGM_CLEAN)) == 0)
444 do_unmark_dirop = 1;
445 mutex_exit(&lfs_lock);
446 sync = sp->seg_flags & SEGM_SYNC;
447 ckp = sp->seg_flags & SEGM_CKP;
448
449 /* We should have a segment summary, and nothing else */
450 KASSERT(sp->cbpp == sp->bpp + 1);
451
452 /* Free allocated segment summary */
453 fs->lfs_offset -= lfs_btofsb(fs, fs->lfs_sumsize);
454 bp = *sp->bpp;
455 lfs_freebuf(fs, bp);
456
457 pool_put(&fs->lfs_bpppool, sp->bpp);
458 sp->bpp = NULL;
459
460 /*
461 * If we're not sync, we're done with sp, get rid of it.
462 * Otherwise, we keep a local copy around but free
463 * fs->lfs_sp so another process can use it (we have to
464 * wait but they don't have to wait for us).
465 */
466 if (!sync)
467 pool_put(&fs->lfs_segpool, sp);
468 fs->lfs_sp = NULL;
469
470 /*
471 * If the I/O count is non-zero, sleep until it reaches zero.
472 * At the moment, the user's process hangs around so we can
473 * sleep.
474 */
475 mutex_enter(&lfs_lock);
476 if (--fs->lfs_iocount == 0) {
477 LFS_DEBUG_COUNTLOCKED("lfs_segunlock");
478 }
479 if (fs->lfs_iocount <= 1)
480 wakeup(&fs->lfs_iocount);
481 mutex_exit(&lfs_lock);
482 /*
483 * If we're not checkpointing, we don't have to block
484 * other processes to wait for a synchronous write
485 * to complete.
486 */
487 if (!ckp) {
488 #ifdef DEBUG
489 LFS_ENTER_LOG("segunlock_std", __FILE__, __LINE__, 0, 0, curproc->p_pid);
490 #endif
491 mutex_enter(&lfs_lock);
492 --fs->lfs_seglock;
493 fs->lfs_lockpid = 0;
494 fs->lfs_locklwp = 0;
495 mutex_exit(&lfs_lock);
496 wakeup(&fs->lfs_seglock);
497 }
498 /*
499 * We let checkpoints happen asynchronously. That means
500 * that during recovery, we have to roll forward between
501 * the two segments described by the first and second
502 * superblocks to make sure that the checkpoint described
503 * by a superblock completed.
504 */
505 mutex_enter(&lfs_lock);
506 while (ckp && sync && fs->lfs_iocount) {
507 (void)mtsleep(&fs->lfs_iocount, PRIBIO + 1,
508 "lfs_iocount", 0, &lfs_lock);
509 DLOG((DLOG_SEG, "sleeping on iocount %x == %d\n", fs, fs->lfs_iocount));
510 }
511 while (sync && sp->seg_iocount) {
512 (void)mtsleep(&sp->seg_iocount, PRIBIO + 1,
513 "seg_iocount", 0, &lfs_lock);
514 DLOG((DLOG_SEG, "sleeping on iocount %x == %d\n", sp, sp->seg_iocount));
515 }
516 mutex_exit(&lfs_lock);
517 if (sync)
518 pool_put(&fs->lfs_segpool, sp);
519
520 if (ckp) {
521 fs->lfs_nactive = 0;
522 /* If we *know* everything's on disk, write both sbs */
523 /* XXX should wait for this one */
524 if (sync)
525 lfs_writesuper(fs, fs->lfs_sboffs[fs->lfs_activesb]);
526 lfs_writesuper(fs, fs->lfs_sboffs[1 - fs->lfs_activesb]);
527 if (!(fs->lfs_ivnode->v_mount->mnt_iflag & IMNT_UNMOUNT)) {
528 lfs_auto_segclean(fs);
529 /* If sync, we can clean the remainder too */
530 if (sync)
531 lfs_auto_segclean(fs);
532 }
533 fs->lfs_activesb = 1 - fs->lfs_activesb;
534 #ifdef DEBUG
535 LFS_ENTER_LOG("segunlock_ckp", __FILE__, __LINE__, 0, 0, curproc->p_pid);
536 #endif
537 mutex_enter(&lfs_lock);
538 --fs->lfs_seglock;
539 fs->lfs_lockpid = 0;
540 fs->lfs_locklwp = 0;
541 mutex_exit(&lfs_lock);
542 wakeup(&fs->lfs_seglock);
543 }
544 /* Reenable fragment size changes */
545 rw_exit(&fs->lfs_fraglock);
546 if (do_unmark_dirop)
547 lfs_unmark_dirop(fs);
548 } else if (fs->lfs_seglock == 0) {
549 mutex_exit(&lfs_lock);
550 panic ("Seglock not held");
551 } else {
552 --fs->lfs_seglock;
553 mutex_exit(&lfs_lock);
554 }
555 }
556
557 /*
558 * Drain dirops and start writer.
559 *
560 * No simple_locks are held when we enter and none are held when we return.
561 */
562 int
563 lfs_writer_enter(struct lfs *fs, const char *wmesg)
564 {
565 int error = 0;
566
567 ASSERT_MAYBE_SEGLOCK(fs);
568 mutex_enter(&lfs_lock);
569
570 /* disallow dirops during flush */
571 fs->lfs_writer++;
572
573 while (fs->lfs_dirops > 0) {
574 ++fs->lfs_diropwait;
575 error = mtsleep(&fs->lfs_writer, PRIBIO+1, wmesg, 0,
576 &lfs_lock);
577 --fs->lfs_diropwait;
578 }
579
580 if (error)
581 fs->lfs_writer--;
582
583 mutex_exit(&lfs_lock);
584
585 return error;
586 }
587
588 void
589 lfs_writer_leave(struct lfs *fs)
590 {
591 bool dowakeup;
592
593 ASSERT_MAYBE_SEGLOCK(fs);
594 mutex_enter(&lfs_lock);
595 dowakeup = !(--fs->lfs_writer);
596 mutex_exit(&lfs_lock);
597 if (dowakeup)
598 wakeup(&fs->lfs_dirops);
599 }
600
601 /*
602 * Unlock, wait for the cleaner, then relock to where we were before.
603 * To be used only at a fairly high level, to address a paucity of free
604 * segments propagated back from lfs_gop_write().
605 */
606 void
607 lfs_segunlock_relock(struct lfs *fs)
608 {
609 int n = fs->lfs_seglock;
610 u_int16_t seg_flags;
611 CLEANERINFO *cip;
612 struct buf *bp;
613
614 if (n == 0)
615 return;
616
617 /* Write anything we've already gathered to disk */
618 lfs_writeseg(fs, fs->lfs_sp);
619
620 /* Tell cleaner */
621 LFS_CLEANERINFO(cip, fs, bp);
622 cip->flags |= LFS_CLEANER_MUST_CLEAN;
623 LFS_SYNC_CLEANERINFO(cip, fs, bp, 1);
624
625 /* Save segment flags for later */
626 seg_flags = fs->lfs_sp->seg_flags;
627
628 fs->lfs_sp->seg_flags |= SEGM_PROT; /* Don't unmark dirop nodes */
629 while(fs->lfs_seglock)
630 lfs_segunlock(fs);
631
632 /* Wait for the cleaner */
633 lfs_wakeup_cleaner(fs);
634 mutex_enter(&lfs_lock);
635 while (LFS_STARVED_FOR_SEGS(fs))
636 mtsleep(&fs->lfs_avail, PRIBIO, "relock", 0,
637 &lfs_lock);
638 mutex_exit(&lfs_lock);
639
640 /* Put the segment lock back the way it was. */
641 while(n--)
642 lfs_seglock(fs, seg_flags);
643
644 /* Cleaner can relax now */
645 LFS_CLEANERINFO(cip, fs, bp);
646 cip->flags &= ~LFS_CLEANER_MUST_CLEAN;
647 LFS_SYNC_CLEANERINFO(cip, fs, bp, 1);
648
649 return;
650 }
651
652 /*
653 * Wake up the cleaner, provided that nowrap is not set.
654 */
655 void
656 lfs_wakeup_cleaner(struct lfs *fs)
657 {
658 if (fs->lfs_nowrap > 0)
659 return;
660
661 wakeup(&fs->lfs_nextseg);
662 wakeup(&lfs_allclean_wakeup);
663 }
664