lfs_bio.c revision 1.150 1 /* $NetBSD: lfs_bio.c,v 1.150 2025/09/15 03:55:24 perseant Exp $ */
2
3 /*-
4 * Copyright (c) 1999, 2000, 2001, 2002, 2003, 2008 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_bio.c 8.10 (Berkeley) 6/10/95
60 */
61
62 #include <sys/cdefs.h>
63 __KERNEL_RCSID(0, "$NetBSD: lfs_bio.c,v 1.150 2025/09/15 03:55:24 perseant Exp $");
64
65 #include <sys/param.h>
66 #include <sys/systm.h>
67 #include <sys/proc.h>
68 #include <sys/buf.h>
69 #include <sys/vnode.h>
70 #include <sys/resourcevar.h>
71 #include <sys/mount.h>
72 #include <sys/kernel.h>
73 #include <sys/kauth.h>
74
75 #include <ufs/lfs/ulfs_inode.h>
76 #include <ufs/lfs/ulfsmount.h>
77 #include <ufs/lfs/ulfs_extern.h>
78
79 #include <ufs/lfs/lfs.h>
80 #include <ufs/lfs/lfs_accessors.h>
81 #include <ufs/lfs/lfs_extern.h>
82 #include <ufs/lfs/lfs_kernel.h>
83
84 #include <uvm/uvm_extern.h>
85
86 /*
87 * LFS block write function.
88 *
89 * XXX
90 * No write cost accounting is done.
91 * This is almost certainly wrong for synchronous operations and NFS.
92 *
93 * protected by lfs_lock.
94 */
95 int locked_queue_count = 0; /* Count of locked-down buffers. */
96 long locked_queue_bytes = 0L; /* Total size of locked buffers. */
97 int lfs_subsys_pages = 0L; /* Total number LFS-written pages */
98 int lfs_fs_pagetrip = 0; /* # of pages to trip per-fs write */
99 int lfs_writing = 0; /* Set if already kicked off a writer
100 because of buffer space */
101 int locked_queue_waiters = 0; /* Number of processes waiting on lq */
102
103 /* Lock and condition variables for above. */
104 kcondvar_t locked_queue_cv;
105 kcondvar_t lfs_writing_cv;
106 kmutex_t lfs_lock;
107 extern kcondvar_t lfs_writerd_cv;
108
109 extern int lfs_dostats;
110
111 /*
112 * reserved number/bytes of locked buffers
113 */
114 int locked_queue_rcount = 0;
115 long locked_queue_rbytes = 0L;
116
117 static int lfs_fits_buf(struct lfs *, int, int);
118 static int lfs_reservebuf(struct lfs *, struct vnode *vp, struct vnode *vp2,
119 int, int);
120 static int lfs_reserveavail(struct lfs *, struct vnode *vp, struct vnode *vp2,
121 int);
122
123 static int
124 lfs_fits_buf(struct lfs *fs, int n, int bytes)
125 {
126 int count_fit, bytes_fit;
127
128 ASSERT_NO_SEGLOCK(fs);
129 KASSERT(mutex_owned(&lfs_lock));
130
131 count_fit =
132 (locked_queue_count + locked_queue_rcount + n <= LFS_WAIT_BUFS);
133 bytes_fit =
134 (locked_queue_bytes + locked_queue_rbytes + bytes <= LFS_WAIT_BYTES);
135
136 #ifdef DEBUG
137 if (!count_fit) {
138 DLOG((DLOG_AVAIL, "lfs_fits_buf: no fit count: %d + %d + %d >= %d\n",
139 locked_queue_count, locked_queue_rcount,
140 n, LFS_WAIT_BUFS));
141 }
142 if (!bytes_fit) {
143 DLOG((DLOG_AVAIL, "lfs_fits_buf: no fit bytes: %ld + %ld + %d >= %ld\n",
144 locked_queue_bytes, locked_queue_rbytes,
145 bytes, LFS_WAIT_BYTES));
146 }
147 #endif /* DEBUG */
148
149 return (count_fit && bytes_fit);
150 }
151
152 /* ARGSUSED */
153 static int
154 lfs_reservebuf(struct lfs *fs, struct vnode *vp,
155 struct vnode *vp2, int n, int bytes)
156 {
157 int cantwait;
158
159 ASSERT_MAYBE_SEGLOCK(fs);
160 KASSERT(locked_queue_rcount >= 0);
161 KASSERT(locked_queue_rbytes >= 0);
162
163 cantwait = (VTOI(vp)->i_state & IN_ADIROP) || fs->lfs_unlockvp == vp;
164 mutex_enter(&lfs_lock);
165 while (!cantwait && n > 0 && !lfs_fits_buf(fs, n, bytes)) {
166 int error;
167
168 DLOG((DLOG_FLUSH, "lfs_reservebuf: flush filesystem %p with checkpoint\n", fs));
169 lfs_flush(fs, SEGM_CKP, 0);
170
171 DLOG((DLOG_AVAIL, "lfs_reservebuf: waiting: count=%d, bytes=%ld\n",
172 locked_queue_count, locked_queue_bytes));
173 ++locked_queue_waiters;
174 cv_broadcast(&lfs_writerd_cv);
175 error = cv_timedwait_sig(&locked_queue_cv, &lfs_lock,
176 hz * LFS_BUFWAIT);
177 --locked_queue_waiters;
178 if (error && error != EWOULDBLOCK) {
179 mutex_exit(&lfs_lock);
180 return error;
181 }
182 }
183
184 locked_queue_rcount += n;
185 locked_queue_rbytes += bytes;
186
187 if (n < 0 && locked_queue_waiters > 0) {
188 DLOG((DLOG_AVAIL, "lfs_reservebuf: broadcast: count=%d, bytes=%ld\n",
189 locked_queue_count, locked_queue_bytes));
190 cv_broadcast(&locked_queue_cv);
191 }
192
193 mutex_exit(&lfs_lock);
194
195 KASSERT(locked_queue_rcount >= 0);
196 KASSERT(locked_queue_rbytes >= 0);
197
198 return 0;
199 }
200
201 /*
202 * Try to reserve some blocks, prior to performing a sensitive operation that
203 * requires the vnode lock to be honored. If there is not enough space, wait
204 * for the space to become available.
205 *
206 * Called with vp locked. (Note nowever that if fsb < 0, vp is ignored.)
207 */
208 static int
209 lfs_reserveavail(struct lfs *fs, struct vnode *vp,
210 struct vnode *vp2, int fsb)
211 {
212 CLEANERINFO *cip;
213 struct buf *bp;
214 int error, slept;
215 int cantwait;
216
217 ASSERT_MAYBE_SEGLOCK(fs);
218 slept = 0;
219 mutex_enter(&lfs_lock);
220 cantwait = (VTOI(vp)->i_state & IN_ADIROP) || fs->lfs_unlockvp == vp;
221 while (!cantwait && fsb > 0 &&
222 !lfs_fits(fs, fsb + fs->lfs_ravail + fs->lfs_favail)) {
223 mutex_exit(&lfs_lock);
224
225 if (!slept) {
226 DLOG((DLOG_AVAIL, "lfs_reserve: waiting for %ld (bfree = %jd,"
227 " est_bfree = %jd)\n",
228 fsb + fs->lfs_ravail + fs->lfs_favail,
229 (intmax_t)lfs_sb_getbfree(fs),
230 (intmax_t)LFS_EST_BFREE(fs)));
231 }
232 ++slept;
233
234 /* Wake up the cleaner */
235 LFS_CLEANERINFO(cip, fs, bp);
236 LFS_SYNC_CLEANERINFO(cip, fs, bp, 0);
237 lfs_wakeup_cleaner(fs);
238
239 mutex_enter(&lfs_lock);
240 /* Cleaner might have run while we were reading, check again */
241 if (lfs_fits(fs, fsb + fs->lfs_ravail + fs->lfs_favail))
242 break;
243
244 error = mtsleep(&fs->lfs_availsleep, PCATCH | PUSER,
245 "lfs_reserve", 0, &lfs_lock);
246 if (error) {
247 mutex_exit(&lfs_lock);
248 return error;
249 }
250 }
251 #ifdef DEBUG
252 if (slept) {
253 DLOG((DLOG_AVAIL, "lfs_reserve: woke up\n"));
254 }
255 #endif
256 fs->lfs_ravail += fsb;
257 mutex_exit(&lfs_lock);
258
259 return 0;
260 }
261
262 #ifdef DIAGNOSTIC
263 int lfs_rescount;
264 int lfs_rescountdirop;
265 #endif
266
267 int
268 lfs_reserve(struct lfs *fs, struct vnode *vp, struct vnode *vp2, int fsb)
269 {
270 int error;
271
272 ASSERT_MAYBE_SEGLOCK(fs);
273 if (vp2) {
274 /* Make sure we're not in the process of reclaiming vp2 */
275 mutex_enter(&lfs_lock);
276 while(fs->lfs_flags & LFS_UNDIROP) {
277 mtsleep(&fs->lfs_flags, PRIBIO + 1, "lfsrundirop", 0,
278 &lfs_lock);
279 }
280 mutex_exit(&lfs_lock);
281 }
282
283 KASSERT(fsb < 0 || VOP_ISLOCKED(vp));
284 KASSERT(vp2 == NULL || fsb < 0 || VOP_ISLOCKED(vp2));
285 KASSERT(vp2 == NULL || vp2 != fs->lfs_unlockvp);
286
287 #ifdef DIAGNOSTIC
288 mutex_enter(&lfs_lock);
289 if (fsb > 0)
290 lfs_rescount++;
291 else if (fsb < 0)
292 lfs_rescount--;
293 if (lfs_rescount < 0)
294 panic("lfs_rescount");
295 mutex_exit(&lfs_lock);
296 #endif
297
298 error = lfs_reserveavail(fs, vp, vp2, fsb);
299 if (error)
300 return error;
301
302 /*
303 * XXX just a guess. should be more precise.
304 */
305 error = lfs_reservebuf(fs, vp, vp2, fsb, lfs_fsbtob(fs, fsb));
306 if (error)
307 lfs_reserveavail(fs, vp, vp2, -fsb);
308
309 return error;
310 }
311
312 int
313 lfs_max_bufs(void)
314 {
315
316 return LFS_MAX_RESOURCE(buf_nbuf(), 1);
317 }
318
319 int
320 lfs_wait_bufs(void)
321 {
322
323 return LFS_WAIT_RESOURCE(buf_nbuf(), 1);
324 }
325
326 int
327 lfs_bwrite(void *v)
328 {
329 struct vop_bwrite_args /* {
330 struct vnode *a_vp;
331 struct buf *a_bp;
332 } */ *ap = v;
333 struct buf *bp = ap->a_bp;
334
335 KASSERTMSG((VTOI(bp->b_vp)->i_lfs->lfs_ronly ||
336 !(bp->b_flags & B_ASYNC)),
337 "bawrite LFS buffer");
338 return lfs_bwrite_ext(bp, 0);
339 }
340
341 /*
342 * Determine if there is enough room currently available to write fsb
343 * blocks. We need enough blocks for the new blocks, the current
344 * inode blocks (including potentially the ifile inode), a summary block,
345 * and the segment usage table, plus an ifile block.
346 */
347 int
348 lfs_fits(struct lfs *fs, int fsb)
349 {
350 int64_t needed;
351
352 ASSERT_NO_SEGLOCK(fs);
353 needed = fsb + lfs_btofsb(fs, lfs_sb_getsumsize(fs)) +
354 ((howmany(lfs_sb_getuinodes(fs) + 1, LFS_INOPB(fs)) +
355 lfs_sb_getsegtabsz(fs) +
356 1) << (lfs_sb_getbshift(fs) - lfs_sb_getffshift(fs)));
357
358 if (needed >= lfs_sb_getavail(fs)) {
359 #ifdef DEBUG
360 DLOG((DLOG_AVAIL, "lfs_fits: no fit: fsb = %ld, uinodes = %ld, "
361 "needed = %jd, avail = %jd\n",
362 (long)fsb, (long)lfs_sb_getuinodes(fs), (intmax_t)needed,
363 (intmax_t)lfs_sb_getavail(fs)));
364 #endif
365 return 0;
366 }
367 return 1;
368 }
369
370 int
371 lfs_availwait(struct lfs *fs, int fsb)
372 {
373 int error;
374 CLEANERINFO *cip;
375 struct buf *cbp;
376
377 ASSERT_NO_SEGLOCK(fs);
378 /* Push cleaner blocks through regardless */
379 mutex_enter(&lfs_lock);
380 if (LFS_SEGLOCK_HELD(fs) &&
381 fs->lfs_sp->seg_flags & (SEGM_CLEAN | SEGM_FORCE_CKP)) {
382 mutex_exit(&lfs_lock);
383 return 0;
384 }
385 mutex_exit(&lfs_lock);
386
387 while (!lfs_fits(fs, fsb)) {
388 /*
389 * Out of space, need cleaner to run.
390 * Update the cleaner info, then wake it up.
391 * Note the cleanerinfo block is on the ifile
392 * so it CANT_WAIT.
393 */
394 LFS_CLEANERINFO(cip, fs, cbp);
395 LFS_SYNC_CLEANERINFO(cip, fs, cbp, 0);
396
397 #ifdef DEBUG
398 DLOG((DLOG_AVAIL, "lfs_availwait: out of available space, "
399 "waiting on cleaner\n"));
400 #endif
401
402 lfs_wakeup_cleaner(fs);
403 KASSERTMSG(!LFS_SEGLOCK_HELD(fs), "lfs_availwait: deadlock");
404 error = tsleep(&fs->lfs_availsleep, PCATCH | PUSER,
405 "cleaner", 0);
406 if (error)
407 return (error);
408 }
409 return 0;
410 }
411
412 int
413 lfs_bwrite_ext(struct buf *bp, int flags)
414 {
415 struct lfs *fs;
416 struct inode *ip;
417 struct vnode *vp;
418 int fsb;
419
420 vp = bp->b_vp;
421 fs = VFSTOULFS(vp->v_mount)->um_lfs;
422
423 ASSERT_MAYBE_SEGLOCK(fs);
424 KASSERT(bp->b_cflags & BC_BUSY);
425 KASSERT(flags & BW_CLEAN || !LFS_IS_MALLOC_BUF(bp));
426 KASSERT((bp->b_flags & B_LOCKED) || !(bp->b_oflags & BO_DELWRI));
427
428 /*
429 * Don't write *any* blocks if we're mounted read-only, or
430 * if we are "already unmounted".
431 *
432 * In particular the cleaner can't write blocks either.
433 */
434 if (fs->lfs_ronly || (lfs_sb_getpflags(fs) & LFS_PF_CLEAN)) {
435 bp->b_oflags &= ~BO_DELWRI;
436 bp->b_flags |= B_READ; /* XXX is this right? --ks */
437 bp->b_error = 0;
438 mutex_enter(&bufcache_lock);
439 LFS_UNLOCK_BUF(bp);
440 if (LFS_IS_MALLOC_BUF(bp))
441 bp->b_cflags &= ~BC_BUSY;
442 else
443 brelsel(bp, 0);
444 mutex_exit(&bufcache_lock);
445 return (fs->lfs_ronly ? EROFS : 0);
446 }
447
448 /*
449 * Set the delayed write flag and use reassignbuf to move the buffer
450 * from the clean list to the dirty one.
451 *
452 * Set the B_LOCKED flag and unlock the buffer, causing brelse to move
453 * the buffer onto the LOCKED free list. This is necessary, otherwise
454 * getnewbuf() would try to reclaim the buffers using bawrite, which
455 * isn't going to work.
456 *
457 * XXX we don't let meta-data writes run out of space because they can
458 * come from the segment writer. We need to make sure that there is
459 * enough space reserved so that there's room to write meta-data
460 * blocks.
461 */
462 if ((bp->b_flags & B_LOCKED) == 0) {
463 fsb = lfs_numfrags(fs, bp->b_bcount);
464
465 ip = VTOI(vp);
466 mutex_enter(&lfs_lock);
467 if (flags & BW_CLEAN) {
468 LFS_SET_UINO(ip, IN_CLEANING);
469 } else {
470 LFS_SET_UINO(ip, IN_MODIFIED);
471 }
472 mutex_exit(&lfs_lock);
473 lfs_sb_subavail(fs, fsb);
474
475 mutex_enter(&bufcache_lock);
476 mutex_enter(vp->v_interlock);
477 bp->b_oflags = (bp->b_oflags | BO_DELWRI) & ~BO_DONE;
478 LFS_LOCK_BUF(bp);
479 bp->b_flags &= ~B_READ;
480 bp->b_error = 0;
481 reassignbuf(bp, bp->b_vp);
482 mutex_exit(vp->v_interlock);
483 } else {
484 mutex_enter(&bufcache_lock);
485 }
486
487 if (bp->b_iodone != NULL)
488 bp->b_cflags &= ~BC_BUSY;
489 else
490 brelsel(bp, 0);
491 mutex_exit(&bufcache_lock);
492
493 return (0);
494 }
495
496 /*
497 * Called and return with the lfs_lock held.
498 */
499 void
500 lfs_flush_fs(struct lfs *fs, int flags)
501 {
502 ASSERT_NO_SEGLOCK(fs);
503 KASSERT(mutex_owned(&lfs_lock));
504 if (fs->lfs_ronly)
505 return;
506
507 if (lfs_dostats)
508 ++lfs_stats.flush_invoked;
509
510 fs->lfs_pdflush = 0;
511 mutex_exit(&lfs_lock);
512 lfs_writer_enter(fs, "fldirop");
513 lfs_segwrite(fs->lfs_ivnode->v_mount, flags);
514 lfs_writer_leave(fs);
515 mutex_enter(&lfs_lock);
516 fs->lfs_favail = 0; /* XXX */
517 }
518
519 /*
520 * This routine initiates segment writes when LFS is consuming too many
521 * resources. Ideally the pageout daemon would be able to direct LFS
522 * more subtly.
523 * XXX We have one static count of locked buffers;
524 * XXX need to think more about the multiple filesystem case.
525 *
526 * Called and return with lfs_lock held.
527 * If fs != NULL, we hold the segment lock for fs.
528 */
529 void
530 lfs_flush(struct lfs *fs, int flags, int only_onefs)
531 {
532 extern u_int64_t locked_fakequeue_count;
533 mount_iterator_t *iter;
534 struct mount *mp;
535 struct lfs *tfs;
536
537 KASSERT(mutex_owned(&lfs_lock));
538 KDASSERT(fs == NULL || !LFS_SEGLOCK_HELD(fs));
539 KASSERT(!(fs == NULL && only_onefs));
540
541 if (lfs_dostats)
542 ++lfs_stats.write_exceeded;
543 if (lfs_writing && !(flags & (SEGM_SYNC|SEGM_CKP))) {
544 DLOG((DLOG_FLUSH, "lfs_flush: not flushing because another flush is active\n"));
545 return;
546 }
547 while (lfs_writing)
548 cv_wait(&lfs_writing_cv, &lfs_lock);
549 lfs_writing = 1;
550
551 mutex_exit(&lfs_lock);
552
553 if (fs != NULL) {
554 if (!(fs->lfs_flags & LFS_NOTYET)
555 && vfs_busy(fs->lfs_ivnode->v_mount))
556 goto errout;
557 mutex_enter(&lfs_lock);
558 lfs_flush_fs(fs, flags);
559 mutex_exit(&lfs_lock);
560 if (!(fs->lfs_flags & LFS_NOTYET))
561 vfs_unbusy(fs->lfs_ivnode->v_mount);
562 }
563 if (!only_onefs) {
564 locked_fakequeue_count = 0;
565 mountlist_iterator_init(&iter);
566 while ((mp = mountlist_iterator_next(iter)) != NULL) {
567 if (strncmp(&mp->mnt_stat.f_fstypename[0], MOUNT_LFS,
568 sizeof(mp->mnt_stat.f_fstypename)) == 0) {
569 tfs = VFSTOULFS(mp)->um_lfs;
570 if (tfs == fs)
571 continue;
572 mutex_enter(&lfs_lock);
573 lfs_flush_fs(tfs, flags);
574 mutex_exit(&lfs_lock);
575 }
576 }
577 mountlist_iterator_destroy(iter);
578 }
579 wakeup(&lfs_subsys_pages);
580
581 errout:
582 mutex_enter(&lfs_lock);
583 KASSERT(lfs_writing);
584 lfs_writing = 0;
585 wakeup(&lfs_writing);
586 }
587
588 #define INOCOUNT(fs) howmany(lfs_sb_getuinodes(fs), LFS_INOPB(fs))
589 #define INOBYTES(fs) (lfs_sb_getuinodes(fs) * DINOSIZE(fs))
590
591 /*
592 * make sure that we don't have too many locked buffers.
593 * flush buffers if needed.
594 */
595 int
596 lfs_check(struct vnode *vp, daddr_t blkno, int flags)
597 {
598 int error;
599 struct lfs *fs;
600 struct inode *ip;
601 extern kcondvar_t lfs_writerd_cv;
602
603 error = 0;
604 ip = VTOI(vp);
605
606 /* If out of buffers, wait on writer */
607 /* XXX KS - if it's the Ifile, we're probably the cleaner! */
608 if (ip->i_number == LFS_IFILE_INUM)
609 return 0;
610 /* If we're being called from inside a dirop, don't sleep */
611 if (ip->i_state & IN_ADIROP)
612 return 0;
613
614 fs = ip->i_lfs;
615
616 ASSERT_NO_SEGLOCK(fs);
617
618 /*
619 * If we would flush below, but dirops are active, sleep.
620 * Note that a dirop cannot ever reach this code!
621 */
622 mutex_enter(&lfs_lock);
623 while (fs->lfs_dirops > 0 &&
624 (locked_queue_count + INOCOUNT(fs) > LFS_WAIT_BUFS ||
625 locked_queue_bytes + INOBYTES(fs) > LFS_WAIT_BYTES ||
626 lfs_subsys_pages > LFS_WAIT_PAGES ||
627 fs->lfs_dirvcount > LFS_MAX_FSDIROP(fs) ||
628 lfs_dirvcount > LFS_MAX_DIROP || fs->lfs_diropwait > 0))
629 {
630 ++fs->lfs_diropwait;
631 mtsleep(&fs->lfs_writer, PRIBIO+1, "bufdirop", 0,
632 &lfs_lock);
633 --fs->lfs_diropwait;
634 }
635
636 #ifdef DEBUG
637 if (locked_queue_count + INOCOUNT(fs) > LFS_MAX_BUFS)
638 DLOG((DLOG_FLUSH, "lfs_check: lqc = %d, max %d\n",
639 locked_queue_count + INOCOUNT(fs), LFS_MAX_BUFS));
640 if (locked_queue_bytes + INOBYTES(fs) > LFS_MAX_BYTES)
641 DLOG((DLOG_FLUSH, "lfs_check: lqb = %ld, max %ld\n",
642 locked_queue_bytes + INOBYTES(fs), LFS_MAX_BYTES));
643 if (lfs_subsys_pages > LFS_MAX_PAGES)
644 DLOG((DLOG_FLUSH, "lfs_check: lssp = %d, max %d\n",
645 lfs_subsys_pages, LFS_MAX_PAGES));
646 if (lfs_fs_pagetrip && fs->lfs_pages > lfs_fs_pagetrip)
647 DLOG((DLOG_FLUSH, "lfs_check: fssp = %d, trip at %d\n",
648 fs->lfs_pages, lfs_fs_pagetrip));
649 if (lfs_dirvcount > LFS_MAX_DIROP)
650 DLOG((DLOG_FLUSH, "lfs_check: ldvc = %d, max %d\n",
651 lfs_dirvcount, LFS_MAX_DIROP));
652 if (fs->lfs_dirvcount > LFS_MAX_FSDIROP(fs))
653 DLOG((DLOG_FLUSH, "lfs_check: lfdvc = %d, max %d\n",
654 fs->lfs_dirvcount, LFS_MAX_FSDIROP(fs)));
655 if (fs->lfs_diropwait > 0)
656 DLOG((DLOG_FLUSH, "lfs_check: ldvw = %d\n",
657 fs->lfs_diropwait));
658 #endif
659
660 /* If there are too many pending dirops, we have to flush them. */
661 if (fs->lfs_dirvcount > LFS_MAX_FSDIROP(fs) ||
662 lfs_dirvcount > LFS_MAX_DIROP || fs->lfs_diropwait > 0) {
663 KASSERT(fs->lfs_dirops == 0);
664 fs->lfs_writer++;
665 mutex_exit(&lfs_lock);
666 lfs_flush_dirops(fs);
667 mutex_enter(&lfs_lock);
668 if (--fs->lfs_writer == 0)
669 cv_broadcast(&fs->lfs_diropscv);
670 KASSERT(fs->lfs_dirops == 0);
671 } else if (locked_queue_count + INOCOUNT(fs) > LFS_MAX_BUFS ||
672 locked_queue_bytes + INOBYTES(fs) > LFS_MAX_BYTES ||
673 lfs_subsys_pages > LFS_MAX_PAGES ||
674 fs->lfs_dirvcount > LFS_MAX_FSDIROP(fs) ||
675 lfs_dirvcount > LFS_MAX_DIROP || fs->lfs_diropwait > 0) {
676 lfs_flush(fs, flags, 0);
677 } else if (lfs_fs_pagetrip && fs->lfs_pages > lfs_fs_pagetrip) {
678 /*
679 * If we didn't flush the whole thing, some filesystems
680 * still might want to be flushed.
681 */
682 ++fs->lfs_pdflush;
683 cv_broadcast(&lfs_writerd_cv);
684 }
685
686 while (locked_queue_count + INOCOUNT(fs) >= LFS_WAIT_BUFS ||
687 locked_queue_bytes + INOBYTES(fs) >= LFS_WAIT_BYTES ||
688 lfs_subsys_pages > LFS_WAIT_PAGES ||
689 fs->lfs_dirvcount > LFS_MAX_FSDIROP(fs) ||
690 lfs_dirvcount > LFS_MAX_DIROP) {
691
692 if (lfs_dostats)
693 ++lfs_stats.wait_exceeded;
694 DLOG((DLOG_AVAIL, "lfs_check: waiting: count=%d, bytes=%ld\n",
695 locked_queue_count, locked_queue_bytes));
696 ++locked_queue_waiters;
697 cv_broadcast(&lfs_writerd_cv);
698 error = cv_timedwait_sig(&locked_queue_cv, &lfs_lock,
699 hz * LFS_BUFWAIT);
700 --locked_queue_waiters;
701 if (error != EWOULDBLOCK)
702 break;
703
704 /*
705 * lfs_flush might not flush all the buffers, if some of the
706 * inodes were locked or if most of them were Ifile blocks
707 * and we weren't asked to checkpoint. Try flushing again
708 * to keep us from blocking indefinitely.
709 */
710 if (locked_queue_count + INOCOUNT(fs) >= LFS_MAX_BUFS ||
711 locked_queue_bytes + INOBYTES(fs) >= LFS_MAX_BYTES) {
712 lfs_flush(fs, flags | SEGM_CKP, 0);
713 }
714 }
715 mutex_exit(&lfs_lock);
716 return (error);
717 }
718
719 /*
720 * Allocate a new buffer header.
721 */
722 struct buf *
723 lfs_newbuf(struct lfs *fs, struct vnode *vp, daddr_t daddr, size_t size, int type)
724 {
725 struct buf *bp;
726 size_t nbytes;
727
728 ASSERT_MAYBE_SEGLOCK(fs);
729 nbytes = roundup(size, lfs_fsbtob(fs, 1));
730
731 bp = getiobuf(NULL, true);
732 if (nbytes) {
733 bp->b_data = lfs_malloc(fs, nbytes, type);
734 /* memset(bp->b_data, 0, nbytes); */
735 }
736 KASSERT(vp != NULL);
737 KASSERT(bp != NULL);
738
739 bp->b_bufsize = size;
740 bp->b_bcount = size;
741 bp->b_lblkno = daddr;
742 bp->b_blkno = daddr;
743 bp->b_error = 0;
744 bp->b_resid = 0;
745 bp->b_iodone = lfs_free_aiodone;
746 bp->b_cflags |= BC_BUSY | BC_NOCACHE;
747 bp->b_private = fs;
748
749 mutex_enter(&bufcache_lock);
750 mutex_enter(vp->v_interlock);
751 bgetvp(vp, bp);
752 mutex_exit(vp->v_interlock);
753 mutex_exit(&bufcache_lock);
754
755 return (bp);
756 }
757
758 void
759 lfs_freebuf(struct lfs *fs, struct buf *bp)
760 {
761 struct vnode *vp;
762
763 if ((vp = bp->b_vp) != NULL) {
764 mutex_enter(&bufcache_lock);
765 mutex_enter(vp->v_interlock);
766 brelvp(bp);
767 mutex_exit(vp->v_interlock);
768 mutex_exit(&bufcache_lock);
769 }
770 if (!(bp->b_cflags & BC_INVAL)) { /* BC_INVAL indicates a "fake" buffer */
771 lfs_free(fs, bp->b_data, LFS_NB_UNKNOWN);
772 bp->b_data = NULL;
773 }
774 putiobuf(bp);
775 }
776
777 int
778 lfs_wait_pages(void)
779 {
780 int active, inactive;
781
782 uvm_estimatepageable(&active, &inactive);
783 return LFS_WAIT_RESOURCE(active + inactive + uvm_availmem(false), 1);
784 }
785
786 int
787 lfs_max_pages(void)
788 {
789 int active, inactive;
790
791 uvm_estimatepageable(&active, &inactive);
792 return LFS_MAX_RESOURCE(active + inactive + uvm_availmem(false), 1);
793 }
794