FreeBSD/Linux Kernel Cross Reference
sys/geom/geom_io.c
1 /*-
2 * Copyright (c) 2002 Poul-Henning Kamp
3 * Copyright (c) 2002 Networks Associates Technology, Inc.
4 * Copyright (c) 2013 The FreeBSD Foundation
5 * All rights reserved.
6 *
7 * This software was developed for the FreeBSD Project by Poul-Henning Kamp
8 * and NAI Labs, the Security Research Division of Network Associates, Inc.
9 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
10 * DARPA CHATS research program.
11 *
12 * Portions of this software were developed by Konstantin Belousov
13 * under sponsorship from the FreeBSD Foundation.
14 *
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
17 * are met:
18 * 1. Redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer.
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in the
22 * documentation and/or other materials provided with the distribution.
23 * 3. The names of the authors may not be used to endorse or promote
24 * products derived from this software without specific prior written
25 * permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 */
39
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD: releng/10.1/sys/geom/geom_io.c 260385 2014-01-07 01:32:23Z scottl $");
42
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/kernel.h>
46 #include <sys/malloc.h>
47 #include <sys/bio.h>
48 #include <sys/ktr.h>
49 #include <sys/proc.h>
50 #include <sys/stack.h>
51 #include <sys/sysctl.h>
52 #include <sys/vmem.h>
53
54 #include <sys/errno.h>
55 #include <geom/geom.h>
56 #include <geom/geom_int.h>
57 #include <sys/devicestat.h>
58
59 #include <vm/uma.h>
60 #include <vm/vm.h>
61 #include <vm/vm_param.h>
62 #include <vm/vm_kern.h>
63 #include <vm/vm_page.h>
64 #include <vm/vm_object.h>
65 #include <vm/vm_extern.h>
66 #include <vm/vm_map.h>
67
68 static int g_io_transient_map_bio(struct bio *bp);
69
70 static struct g_bioq g_bio_run_down;
71 static struct g_bioq g_bio_run_up;
72 static struct g_bioq g_bio_run_task;
73
74 static u_int pace;
75 static uma_zone_t biozone;
76
77 /*
78 * The head of the list of classifiers used in g_io_request.
79 * Use g_register_classifier() and g_unregister_classifier()
80 * to add/remove entries to the list.
81 * Classifiers are invoked in registration order.
82 */
83 static TAILQ_HEAD(g_classifier_tailq, g_classifier_hook)
84 g_classifier_tailq = TAILQ_HEAD_INITIALIZER(g_classifier_tailq);
85
86 #include <machine/atomic.h>
87
88 static void
89 g_bioq_lock(struct g_bioq *bq)
90 {
91
92 mtx_lock(&bq->bio_queue_lock);
93 }
94
95 static void
96 g_bioq_unlock(struct g_bioq *bq)
97 {
98
99 mtx_unlock(&bq->bio_queue_lock);
100 }
101
102 #if 0
103 static void
104 g_bioq_destroy(struct g_bioq *bq)
105 {
106
107 mtx_destroy(&bq->bio_queue_lock);
108 }
109 #endif
110
111 static void
112 g_bioq_init(struct g_bioq *bq)
113 {
114
115 TAILQ_INIT(&bq->bio_queue);
116 mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF);
117 }
118
119 static struct bio *
120 g_bioq_first(struct g_bioq *bq)
121 {
122 struct bio *bp;
123
124 bp = TAILQ_FIRST(&bq->bio_queue);
125 if (bp != NULL) {
126 KASSERT((bp->bio_flags & BIO_ONQUEUE),
127 ("Bio not on queue bp=%p target %p", bp, bq));
128 bp->bio_flags &= ~BIO_ONQUEUE;
129 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue);
130 bq->bio_queue_length--;
131 }
132 return (bp);
133 }
134
135 struct bio *
136 g_new_bio(void)
137 {
138 struct bio *bp;
139
140 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO);
141 #ifdef KTR
142 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
143 struct stack st;
144
145 CTR1(KTR_GEOM, "g_new_bio(): %p", bp);
146 stack_save(&st);
147 CTRSTACK(KTR_GEOM, &st, 3, 0);
148 }
149 #endif
150 return (bp);
151 }
152
153 struct bio *
154 g_alloc_bio(void)
155 {
156 struct bio *bp;
157
158 bp = uma_zalloc(biozone, M_WAITOK | M_ZERO);
159 #ifdef KTR
160 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
161 struct stack st;
162
163 CTR1(KTR_GEOM, "g_alloc_bio(): %p", bp);
164 stack_save(&st);
165 CTRSTACK(KTR_GEOM, &st, 3, 0);
166 }
167 #endif
168 return (bp);
169 }
170
171 void
172 g_destroy_bio(struct bio *bp)
173 {
174 #ifdef KTR
175 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
176 struct stack st;
177
178 CTR1(KTR_GEOM, "g_destroy_bio(): %p", bp);
179 stack_save(&st);
180 CTRSTACK(KTR_GEOM, &st, 3, 0);
181 }
182 #endif
183 uma_zfree(biozone, bp);
184 }
185
186 struct bio *
187 g_clone_bio(struct bio *bp)
188 {
189 struct bio *bp2;
190
191 bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO);
192 if (bp2 != NULL) {
193 bp2->bio_parent = bp;
194 bp2->bio_cmd = bp->bio_cmd;
195 /*
196 * BIO_ORDERED flag may be used by disk drivers to enforce
197 * ordering restrictions, so this flag needs to be cloned.
198 * BIO_UNMAPPED should be inherited, to properly indicate
199 * which way the buffer is passed.
200 * Other bio flags are not suitable for cloning.
201 */
202 bp2->bio_flags = bp->bio_flags & (BIO_ORDERED | BIO_UNMAPPED);
203 bp2->bio_length = bp->bio_length;
204 bp2->bio_offset = bp->bio_offset;
205 bp2->bio_data = bp->bio_data;
206 bp2->bio_ma = bp->bio_ma;
207 bp2->bio_ma_n = bp->bio_ma_n;
208 bp2->bio_ma_offset = bp->bio_ma_offset;
209 bp2->bio_attribute = bp->bio_attribute;
210 /* Inherit classification info from the parent */
211 bp2->bio_classifier1 = bp->bio_classifier1;
212 bp2->bio_classifier2 = bp->bio_classifier2;
213 bp->bio_children++;
214 }
215 #ifdef KTR
216 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
217 struct stack st;
218
219 CTR2(KTR_GEOM, "g_clone_bio(%p): %p", bp, bp2);
220 stack_save(&st);
221 CTRSTACK(KTR_GEOM, &st, 3, 0);
222 }
223 #endif
224 return(bp2);
225 }
226
227 struct bio *
228 g_duplicate_bio(struct bio *bp)
229 {
230 struct bio *bp2;
231
232 bp2 = uma_zalloc(biozone, M_WAITOK | M_ZERO);
233 bp2->bio_flags = bp->bio_flags & BIO_UNMAPPED;
234 bp2->bio_parent = bp;
235 bp2->bio_cmd = bp->bio_cmd;
236 bp2->bio_length = bp->bio_length;
237 bp2->bio_offset = bp->bio_offset;
238 bp2->bio_data = bp->bio_data;
239 bp2->bio_ma = bp->bio_ma;
240 bp2->bio_ma_n = bp->bio_ma_n;
241 bp2->bio_ma_offset = bp->bio_ma_offset;
242 bp2->bio_attribute = bp->bio_attribute;
243 bp->bio_children++;
244 #ifdef KTR
245 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
246 struct stack st;
247
248 CTR2(KTR_GEOM, "g_duplicate_bio(%p): %p", bp, bp2);
249 stack_save(&st);
250 CTRSTACK(KTR_GEOM, &st, 3, 0);
251 }
252 #endif
253 return(bp2);
254 }
255
256 void
257 g_io_init()
258 {
259
260 g_bioq_init(&g_bio_run_down);
261 g_bioq_init(&g_bio_run_up);
262 g_bioq_init(&g_bio_run_task);
263 biozone = uma_zcreate("g_bio", sizeof (struct bio),
264 NULL, NULL,
265 NULL, NULL,
266 0, 0);
267 }
268
269 int
270 g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr)
271 {
272 struct bio *bp;
273 int error;
274
275 g_trace(G_T_BIO, "bio_getattr(%s)", attr);
276 bp = g_alloc_bio();
277 bp->bio_cmd = BIO_GETATTR;
278 bp->bio_done = NULL;
279 bp->bio_attribute = attr;
280 bp->bio_length = *len;
281 bp->bio_data = ptr;
282 g_io_request(bp, cp);
283 error = biowait(bp, "ggetattr");
284 *len = bp->bio_completed;
285 g_destroy_bio(bp);
286 return (error);
287 }
288
289 int
290 g_io_flush(struct g_consumer *cp)
291 {
292 struct bio *bp;
293 int error;
294
295 g_trace(G_T_BIO, "bio_flush(%s)", cp->provider->name);
296 bp = g_alloc_bio();
297 bp->bio_cmd = BIO_FLUSH;
298 bp->bio_flags |= BIO_ORDERED;
299 bp->bio_done = NULL;
300 bp->bio_attribute = NULL;
301 bp->bio_offset = cp->provider->mediasize;
302 bp->bio_length = 0;
303 bp->bio_data = NULL;
304 g_io_request(bp, cp);
305 error = biowait(bp, "gflush");
306 g_destroy_bio(bp);
307 return (error);
308 }
309
310 static int
311 g_io_check(struct bio *bp)
312 {
313 struct g_consumer *cp;
314 struct g_provider *pp;
315 off_t excess;
316 int error;
317
318 cp = bp->bio_from;
319 pp = bp->bio_to;
320
321 /* Fail if access counters dont allow the operation */
322 switch(bp->bio_cmd) {
323 case BIO_READ:
324 case BIO_GETATTR:
325 if (cp->acr == 0)
326 return (EPERM);
327 break;
328 case BIO_WRITE:
329 case BIO_DELETE:
330 case BIO_FLUSH:
331 if (cp->acw == 0)
332 return (EPERM);
333 break;
334 default:
335 return (EPERM);
336 }
337 /* if provider is marked for error, don't disturb. */
338 if (pp->error)
339 return (pp->error);
340 if (cp->flags & G_CF_ORPHAN)
341 return (ENXIO);
342
343 switch(bp->bio_cmd) {
344 case BIO_READ:
345 case BIO_WRITE:
346 case BIO_DELETE:
347 /* Zero sectorsize or mediasize is probably a lack of media. */
348 if (pp->sectorsize == 0 || pp->mediasize == 0)
349 return (ENXIO);
350 /* Reject I/O not on sector boundary */
351 if (bp->bio_offset % pp->sectorsize)
352 return (EINVAL);
353 /* Reject I/O not integral sector long */
354 if (bp->bio_length % pp->sectorsize)
355 return (EINVAL);
356 /* Reject requests before or past the end of media. */
357 if (bp->bio_offset < 0)
358 return (EIO);
359 if (bp->bio_offset > pp->mediasize)
360 return (EIO);
361
362 /* Truncate requests to the end of providers media. */
363 excess = bp->bio_offset + bp->bio_length;
364 if (excess > bp->bio_to->mediasize) {
365 KASSERT((bp->bio_flags & BIO_UNMAPPED) == 0 ||
366 round_page(bp->bio_ma_offset +
367 bp->bio_length) / PAGE_SIZE == bp->bio_ma_n,
368 ("excess bio %p too short", bp));
369 excess -= bp->bio_to->mediasize;
370 bp->bio_length -= excess;
371 if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
372 bp->bio_ma_n = round_page(bp->bio_ma_offset +
373 bp->bio_length) / PAGE_SIZE;
374 }
375 if (excess > 0)
376 CTR3(KTR_GEOM, "g_down truncated bio "
377 "%p provider %s by %d", bp,
378 bp->bio_to->name, excess);
379 }
380
381 /* Deliver zero length transfers right here. */
382 if (bp->bio_length == 0) {
383 CTR2(KTR_GEOM, "g_down terminated 0-length "
384 "bp %p provider %s", bp, bp->bio_to->name);
385 return (0);
386 }
387
388 if ((bp->bio_flags & BIO_UNMAPPED) != 0 &&
389 (bp->bio_to->flags & G_PF_ACCEPT_UNMAPPED) == 0 &&
390 (bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE)) {
391 if ((error = g_io_transient_map_bio(bp)) >= 0)
392 return (error);
393 }
394 break;
395 default:
396 break;
397 }
398 return (EJUSTRETURN);
399 }
400
401 /*
402 * bio classification support.
403 *
404 * g_register_classifier() and g_unregister_classifier()
405 * are used to add/remove a classifier from the list.
406 * The list is protected using the g_bio_run_down lock,
407 * because the classifiers are called in this path.
408 *
409 * g_io_request() passes bio's that are not already classified
410 * (i.e. those with bio_classifier1 == NULL) to g_run_classifiers().
411 * Classifiers can store their result in the two fields
412 * bio_classifier1 and bio_classifier2.
413 * A classifier that updates one of the fields should
414 * return a non-zero value.
415 * If no classifier updates the field, g_run_classifiers() sets
416 * bio_classifier1 = BIO_NOTCLASSIFIED to avoid further calls.
417 */
418
419 int
420 g_register_classifier(struct g_classifier_hook *hook)
421 {
422
423 g_bioq_lock(&g_bio_run_down);
424 TAILQ_INSERT_TAIL(&g_classifier_tailq, hook, link);
425 g_bioq_unlock(&g_bio_run_down);
426
427 return (0);
428 }
429
430 void
431 g_unregister_classifier(struct g_classifier_hook *hook)
432 {
433 struct g_classifier_hook *entry;
434
435 g_bioq_lock(&g_bio_run_down);
436 TAILQ_FOREACH(entry, &g_classifier_tailq, link) {
437 if (entry == hook) {
438 TAILQ_REMOVE(&g_classifier_tailq, hook, link);
439 break;
440 }
441 }
442 g_bioq_unlock(&g_bio_run_down);
443 }
444
445 static void
446 g_run_classifiers(struct bio *bp)
447 {
448 struct g_classifier_hook *hook;
449 int classified = 0;
450
451 TAILQ_FOREACH(hook, &g_classifier_tailq, link)
452 classified |= hook->func(hook->arg, bp);
453
454 if (!classified)
455 bp->bio_classifier1 = BIO_NOTCLASSIFIED;
456 }
457
458 void
459 g_io_request(struct bio *bp, struct g_consumer *cp)
460 {
461 struct g_provider *pp;
462 struct mtx *mtxp;
463 int direct, error, first;
464
465 KASSERT(cp != NULL, ("NULL cp in g_io_request"));
466 KASSERT(bp != NULL, ("NULL bp in g_io_request"));
467 pp = cp->provider;
468 KASSERT(pp != NULL, ("consumer not attached in g_io_request"));
469 #ifdef DIAGNOSTIC
470 KASSERT(bp->bio_driver1 == NULL,
471 ("bio_driver1 used by the consumer (geom %s)", cp->geom->name));
472 KASSERT(bp->bio_driver2 == NULL,
473 ("bio_driver2 used by the consumer (geom %s)", cp->geom->name));
474 KASSERT(bp->bio_pflags == 0,
475 ("bio_pflags used by the consumer (geom %s)", cp->geom->name));
476 /*
477 * Remember consumer's private fields, so we can detect if they were
478 * modified by the provider.
479 */
480 bp->_bio_caller1 = bp->bio_caller1;
481 bp->_bio_caller2 = bp->bio_caller2;
482 bp->_bio_cflags = bp->bio_cflags;
483 #endif
484
485 if (bp->bio_cmd & (BIO_READ|BIO_WRITE|BIO_GETATTR)) {
486 KASSERT(bp->bio_data != NULL,
487 ("NULL bp->data in g_io_request(cmd=%hhu)", bp->bio_cmd));
488 }
489 if (bp->bio_cmd & (BIO_DELETE|BIO_FLUSH)) {
490 KASSERT(bp->bio_data == NULL,
491 ("non-NULL bp->data in g_io_request(cmd=%hhu)",
492 bp->bio_cmd));
493 }
494 if (bp->bio_cmd & (BIO_READ|BIO_WRITE|BIO_DELETE)) {
495 KASSERT(bp->bio_offset % cp->provider->sectorsize == 0,
496 ("wrong offset %jd for sectorsize %u",
497 bp->bio_offset, cp->provider->sectorsize));
498 KASSERT(bp->bio_length % cp->provider->sectorsize == 0,
499 ("wrong length %jd for sectorsize %u",
500 bp->bio_length, cp->provider->sectorsize));
501 }
502
503 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d",
504 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd);
505
506 bp->bio_from = cp;
507 bp->bio_to = pp;
508 bp->bio_error = 0;
509 bp->bio_completed = 0;
510
511 KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
512 ("Bio already on queue bp=%p", bp));
513 if ((g_collectstats & G_STATS_CONSUMERS) != 0 ||
514 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL))
515 binuptime(&bp->bio_t0);
516 else
517 getbinuptime(&bp->bio_t0);
518
519 #ifdef GET_STACK_USAGE
520 direct = (cp->flags & G_CF_DIRECT_SEND) &&
521 (pp->flags & G_PF_DIRECT_RECEIVE) &&
522 !g_is_geom_thread(curthread) &&
523 (((pp->flags & G_PF_ACCEPT_UNMAPPED) == 0 &&
524 (bp->bio_flags & BIO_UNMAPPED) != 0) || THREAD_CAN_SLEEP());
525 if (direct) {
526 /* Block direct execution if less then half of stack left. */
527 size_t st, su;
528 GET_STACK_USAGE(st, su);
529 if (su * 2 > st)
530 direct = 0;
531 }
532 #else
533 direct = 0;
534 #endif
535
536 if (!TAILQ_EMPTY(&g_classifier_tailq) && !bp->bio_classifier1) {
537 g_bioq_lock(&g_bio_run_down);
538 g_run_classifiers(bp);
539 g_bioq_unlock(&g_bio_run_down);
540 }
541
542 /*
543 * The statistics collection is lockless, as such, but we
544 * can not update one instance of the statistics from more
545 * than one thread at a time, so grab the lock first.
546 */
547 mtxp = mtx_pool_find(mtxpool_sleep, pp);
548 mtx_lock(mtxp);
549 if (g_collectstats & G_STATS_PROVIDERS)
550 devstat_start_transaction(pp->stat, &bp->bio_t0);
551 if (g_collectstats & G_STATS_CONSUMERS)
552 devstat_start_transaction(cp->stat, &bp->bio_t0);
553 pp->nstart++;
554 cp->nstart++;
555 mtx_unlock(mtxp);
556
557 if (direct) {
558 error = g_io_check(bp);
559 if (error >= 0) {
560 CTR3(KTR_GEOM, "g_io_request g_io_check on bp %p "
561 "provider %s returned %d", bp, bp->bio_to->name,
562 error);
563 g_io_deliver(bp, error);
564 return;
565 }
566 bp->bio_to->geom->start(bp);
567 } else {
568 g_bioq_lock(&g_bio_run_down);
569 first = TAILQ_EMPTY(&g_bio_run_down.bio_queue);
570 TAILQ_INSERT_TAIL(&g_bio_run_down.bio_queue, bp, bio_queue);
571 bp->bio_flags |= BIO_ONQUEUE;
572 g_bio_run_down.bio_queue_length++;
573 g_bioq_unlock(&g_bio_run_down);
574 /* Pass it on down. */
575 if (first)
576 wakeup(&g_wait_down);
577 }
578 }
579
580 void
581 g_io_deliver(struct bio *bp, int error)
582 {
583 struct bintime now;
584 struct g_consumer *cp;
585 struct g_provider *pp;
586 struct mtx *mtxp;
587 int direct, first;
588
589 KASSERT(bp != NULL, ("NULL bp in g_io_deliver"));
590 pp = bp->bio_to;
591 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver"));
592 cp = bp->bio_from;
593 if (cp == NULL) {
594 bp->bio_error = error;
595 bp->bio_done(bp);
596 return;
597 }
598 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver"));
599 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver"));
600 #ifdef DIAGNOSTIC
601 /*
602 * Some classes - GJournal in particular - can modify bio's
603 * private fields while the bio is in transit; G_GEOM_VOLATILE_BIO
604 * flag means it's an expected behaviour for that particular geom.
605 */
606 if ((cp->geom->flags & G_GEOM_VOLATILE_BIO) == 0) {
607 KASSERT(bp->bio_caller1 == bp->_bio_caller1,
608 ("bio_caller1 used by the provider %s", pp->name));
609 KASSERT(bp->bio_caller2 == bp->_bio_caller2,
610 ("bio_caller2 used by the provider %s", pp->name));
611 KASSERT(bp->bio_cflags == bp->_bio_cflags,
612 ("bio_cflags used by the provider %s", pp->name));
613 }
614 #endif
615 KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0"));
616 KASSERT(bp->bio_completed <= bp->bio_length,
617 ("bio_completed can't be greater than bio_length"));
618
619 g_trace(G_T_BIO,
620 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd",
621 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error,
622 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length);
623
624 KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
625 ("Bio already on queue bp=%p", bp));
626
627 /*
628 * XXX: next two doesn't belong here
629 */
630 bp->bio_bcount = bp->bio_length;
631 bp->bio_resid = bp->bio_bcount - bp->bio_completed;
632
633 #ifdef GET_STACK_USAGE
634 direct = (pp->flags & G_PF_DIRECT_SEND) &&
635 (cp->flags & G_CF_DIRECT_RECEIVE) &&
636 !g_is_geom_thread(curthread);
637 if (direct) {
638 /* Block direct execution if less then half of stack left. */
639 size_t st, su;
640 GET_STACK_USAGE(st, su);
641 if (su * 2 > st)
642 direct = 0;
643 }
644 #else
645 direct = 0;
646 #endif
647
648 /*
649 * The statistics collection is lockless, as such, but we
650 * can not update one instance of the statistics from more
651 * than one thread at a time, so grab the lock first.
652 */
653 if ((g_collectstats & G_STATS_CONSUMERS) != 0 ||
654 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL))
655 binuptime(&now);
656 mtxp = mtx_pool_find(mtxpool_sleep, cp);
657 mtx_lock(mtxp);
658 if (g_collectstats & G_STATS_PROVIDERS)
659 devstat_end_transaction_bio_bt(pp->stat, bp, &now);
660 if (g_collectstats & G_STATS_CONSUMERS)
661 devstat_end_transaction_bio_bt(cp->stat, bp, &now);
662 cp->nend++;
663 pp->nend++;
664 mtx_unlock(mtxp);
665
666 if (error != ENOMEM) {
667 bp->bio_error = error;
668 if (direct) {
669 biodone(bp);
670 } else {
671 g_bioq_lock(&g_bio_run_up);
672 first = TAILQ_EMPTY(&g_bio_run_up.bio_queue);
673 TAILQ_INSERT_TAIL(&g_bio_run_up.bio_queue, bp, bio_queue);
674 bp->bio_flags |= BIO_ONQUEUE;
675 g_bio_run_up.bio_queue_length++;
676 g_bioq_unlock(&g_bio_run_up);
677 if (first)
678 wakeup(&g_wait_up);
679 }
680 return;
681 }
682
683 if (bootverbose)
684 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name);
685 bp->bio_children = 0;
686 bp->bio_inbed = 0;
687 bp->bio_driver1 = NULL;
688 bp->bio_driver2 = NULL;
689 bp->bio_pflags = 0;
690 g_io_request(bp, cp);
691 pace++;
692 return;
693 }
694
695 SYSCTL_DECL(_kern_geom);
696
697 static long transient_maps;
698 SYSCTL_LONG(_kern_geom, OID_AUTO, transient_maps, CTLFLAG_RD,
699 &transient_maps, 0,
700 "Total count of the transient mapping requests");
701 u_int transient_map_retries = 10;
702 SYSCTL_UINT(_kern_geom, OID_AUTO, transient_map_retries, CTLFLAG_RW,
703 &transient_map_retries, 0,
704 "Max count of retries used before giving up on creating transient map");
705 int transient_map_hard_failures;
706 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_hard_failures, CTLFLAG_RD,
707 &transient_map_hard_failures, 0,
708 "Failures to establish the transient mapping due to retry attempts "
709 "exhausted");
710 int transient_map_soft_failures;
711 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_soft_failures, CTLFLAG_RD,
712 &transient_map_soft_failures, 0,
713 "Count of retried failures to establish the transient mapping");
714 int inflight_transient_maps;
715 SYSCTL_INT(_kern_geom, OID_AUTO, inflight_transient_maps, CTLFLAG_RD,
716 &inflight_transient_maps, 0,
717 "Current count of the active transient maps");
718
719 static int
720 g_io_transient_map_bio(struct bio *bp)
721 {
722 vm_offset_t addr;
723 long size;
724 u_int retried;
725
726 KASSERT(unmapped_buf_allowed, ("unmapped disabled"));
727
728 size = round_page(bp->bio_ma_offset + bp->bio_length);
729 KASSERT(size / PAGE_SIZE == bp->bio_ma_n, ("Bio too short %p", bp));
730 addr = 0;
731 retried = 0;
732 atomic_add_long(&transient_maps, 1);
733 retry:
734 if (vmem_alloc(transient_arena, size, M_BESTFIT | M_NOWAIT, &addr)) {
735 if (transient_map_retries != 0 &&
736 retried >= transient_map_retries) {
737 CTR2(KTR_GEOM, "g_down cannot map bp %p provider %s",
738 bp, bp->bio_to->name);
739 atomic_add_int(&transient_map_hard_failures, 1);
740 return (EDEADLK/* XXXKIB */);
741 } else {
742 /*
743 * Naive attempt to quisce the I/O to get more
744 * in-flight requests completed and defragment
745 * the transient_arena.
746 */
747 CTR3(KTR_GEOM, "g_down retrymap bp %p provider %s r %d",
748 bp, bp->bio_to->name, retried);
749 pause("g_d_tra", hz / 10);
750 retried++;
751 atomic_add_int(&transient_map_soft_failures, 1);
752 goto retry;
753 }
754 }
755 atomic_add_int(&inflight_transient_maps, 1);
756 pmap_qenter((vm_offset_t)addr, bp->bio_ma, OFF_TO_IDX(size));
757 bp->bio_data = (caddr_t)addr + bp->bio_ma_offset;
758 bp->bio_flags |= BIO_TRANSIENT_MAPPING;
759 bp->bio_flags &= ~BIO_UNMAPPED;
760 return (EJUSTRETURN);
761 }
762
763 void
764 g_io_schedule_down(struct thread *tp __unused)
765 {
766 struct bio *bp;
767 int error;
768
769 for(;;) {
770 g_bioq_lock(&g_bio_run_down);
771 bp = g_bioq_first(&g_bio_run_down);
772 if (bp == NULL) {
773 CTR0(KTR_GEOM, "g_down going to sleep");
774 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock,
775 PRIBIO | PDROP, "-", 0);
776 continue;
777 }
778 CTR0(KTR_GEOM, "g_down has work to do");
779 g_bioq_unlock(&g_bio_run_down);
780 if (pace > 0) {
781 CTR1(KTR_GEOM, "g_down pacing self (pace %d)", pace);
782 pause("g_down", hz/10);
783 pace--;
784 }
785 CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp,
786 bp->bio_to->name);
787 error = g_io_check(bp);
788 if (error >= 0) {
789 CTR3(KTR_GEOM, "g_down g_io_check on bp %p provider "
790 "%s returned %d", bp, bp->bio_to->name, error);
791 g_io_deliver(bp, error);
792 continue;
793 }
794 THREAD_NO_SLEEPING();
795 CTR4(KTR_GEOM, "g_down starting bp %p provider %s off %ld "
796 "len %ld", bp, bp->bio_to->name, bp->bio_offset,
797 bp->bio_length);
798 bp->bio_to->geom->start(bp);
799 THREAD_SLEEPING_OK();
800 }
801 }
802
803 void
804 bio_taskqueue(struct bio *bp, bio_task_t *func, void *arg)
805 {
806 bp->bio_task = func;
807 bp->bio_task_arg = arg;
808 /*
809 * The taskqueue is actually just a second queue off the "up"
810 * queue, so we use the same lock.
811 */
812 g_bioq_lock(&g_bio_run_up);
813 KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
814 ("Bio already on queue bp=%p target taskq", bp));
815 bp->bio_flags |= BIO_ONQUEUE;
816 TAILQ_INSERT_TAIL(&g_bio_run_task.bio_queue, bp, bio_queue);
817 g_bio_run_task.bio_queue_length++;
818 wakeup(&g_wait_up);
819 g_bioq_unlock(&g_bio_run_up);
820 }
821
822
823 void
824 g_io_schedule_up(struct thread *tp __unused)
825 {
826 struct bio *bp;
827 for(;;) {
828 g_bioq_lock(&g_bio_run_up);
829 bp = g_bioq_first(&g_bio_run_task);
830 if (bp != NULL) {
831 g_bioq_unlock(&g_bio_run_up);
832 THREAD_NO_SLEEPING();
833 CTR1(KTR_GEOM, "g_up processing task bp %p", bp);
834 bp->bio_task(bp->bio_task_arg);
835 THREAD_SLEEPING_OK();
836 continue;
837 }
838 bp = g_bioq_first(&g_bio_run_up);
839 if (bp != NULL) {
840 g_bioq_unlock(&g_bio_run_up);
841 THREAD_NO_SLEEPING();
842 CTR4(KTR_GEOM, "g_up biodone bp %p provider %s off "
843 "%jd len %ld", bp, bp->bio_to->name,
844 bp->bio_offset, bp->bio_length);
845 biodone(bp);
846 THREAD_SLEEPING_OK();
847 continue;
848 }
849 CTR0(KTR_GEOM, "g_up going to sleep");
850 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock,
851 PRIBIO | PDROP, "-", 0);
852 }
853 }
854
855 void *
856 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error)
857 {
858 struct bio *bp;
859 void *ptr;
860 int errorc;
861
862 KASSERT(length > 0 && length >= cp->provider->sectorsize &&
863 length <= MAXPHYS, ("g_read_data(): invalid length %jd",
864 (intmax_t)length));
865
866 bp = g_alloc_bio();
867 bp->bio_cmd = BIO_READ;
868 bp->bio_done = NULL;
869 bp->bio_offset = offset;
870 bp->bio_length = length;
871 ptr = g_malloc(length, M_WAITOK);
872 bp->bio_data = ptr;
873 g_io_request(bp, cp);
874 errorc = biowait(bp, "gread");
875 if (error != NULL)
876 *error = errorc;
877 g_destroy_bio(bp);
878 if (errorc) {
879 g_free(ptr);
880 ptr = NULL;
881 }
882 return (ptr);
883 }
884
885 int
886 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length)
887 {
888 struct bio *bp;
889 int error;
890
891 KASSERT(length > 0 && length >= cp->provider->sectorsize &&
892 length <= MAXPHYS, ("g_write_data(): invalid length %jd",
893 (intmax_t)length));
894
895 bp = g_alloc_bio();
896 bp->bio_cmd = BIO_WRITE;
897 bp->bio_done = NULL;
898 bp->bio_offset = offset;
899 bp->bio_length = length;
900 bp->bio_data = ptr;
901 g_io_request(bp, cp);
902 error = biowait(bp, "gwrite");
903 g_destroy_bio(bp);
904 return (error);
905 }
906
907 int
908 g_delete_data(struct g_consumer *cp, off_t offset, off_t length)
909 {
910 struct bio *bp;
911 int error;
912
913 KASSERT(length > 0 && length >= cp->provider->sectorsize,
914 ("g_delete_data(): invalid length %jd", (intmax_t)length));
915
916 bp = g_alloc_bio();
917 bp->bio_cmd = BIO_DELETE;
918 bp->bio_done = NULL;
919 bp->bio_offset = offset;
920 bp->bio_length = length;
921 bp->bio_data = NULL;
922 g_io_request(bp, cp);
923 error = biowait(bp, "gdelete");
924 g_destroy_bio(bp);
925 return (error);
926 }
927
928 void
929 g_print_bio(struct bio *bp)
930 {
931 const char *pname, *cmd = NULL;
932
933 if (bp->bio_to != NULL)
934 pname = bp->bio_to->name;
935 else
936 pname = "[unknown]";
937
938 switch (bp->bio_cmd) {
939 case BIO_GETATTR:
940 cmd = "GETATTR";
941 printf("%s[%s(attr=%s)]", pname, cmd, bp->bio_attribute);
942 return;
943 case BIO_FLUSH:
944 cmd = "FLUSH";
945 printf("%s[%s]", pname, cmd);
946 return;
947 case BIO_READ:
948 cmd = "READ";
949 break;
950 case BIO_WRITE:
951 cmd = "WRITE";
952 break;
953 case BIO_DELETE:
954 cmd = "DELETE";
955 break;
956 default:
957 cmd = "UNKNOWN";
958 printf("%s[%s()]", pname, cmd);
959 return;
960 }
961 printf("%s[%s(offset=%jd, length=%jd)]", pname, cmd,
962 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length);
963 }
Cache object: 36be1f3bcd623f92df41e225db4296ea
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