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: stable/9/sys/geom/geom_io.c 265671 2014-05-08 12:26:08Z mav $");
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
53 #include <sys/errno.h>
54 #include <geom/geom.h>
55 #include <geom/geom_int.h>
56 #include <sys/devicestat.h>
57
58 #include <vm/uma.h>
59 #include <vm/vm.h>
60 #include <vm/vm_param.h>
61 #include <vm/vm_kern.h>
62 #include <vm/vm_page.h>
63 #include <vm/vm_object.h>
64 #include <vm/vm_extern.h>
65 #include <vm/vm_map.h>
66
67 static struct g_bioq g_bio_run_down;
68 static struct g_bioq g_bio_run_up;
69 static struct g_bioq g_bio_run_task;
70
71 static u_int pace;
72 static uma_zone_t biozone;
73
74 /*
75 * The head of the list of classifiers used in g_io_request.
76 * Use g_register_classifier() and g_unregister_classifier()
77 * to add/remove entries to the list.
78 * Classifiers are invoked in registration order.
79 */
80 static TAILQ_HEAD(g_classifier_tailq, g_classifier_hook)
81 g_classifier_tailq = TAILQ_HEAD_INITIALIZER(g_classifier_tailq);
82
83 #include <machine/atomic.h>
84
85 static void
g_bioq_lock(struct g_bioq * bq)86 g_bioq_lock(struct g_bioq *bq)
87 {
88
89 mtx_lock(&bq->bio_queue_lock);
90 }
91
92 static void
g_bioq_unlock(struct g_bioq * bq)93 g_bioq_unlock(struct g_bioq *bq)
94 {
95
96 mtx_unlock(&bq->bio_queue_lock);
97 }
98
99 #if 0
100 static void
101 g_bioq_destroy(struct g_bioq *bq)
102 {
103
104 mtx_destroy(&bq->bio_queue_lock);
105 }
106 #endif
107
108 static void
g_bioq_init(struct g_bioq * bq)109 g_bioq_init(struct g_bioq *bq)
110 {
111
112 TAILQ_INIT(&bq->bio_queue);
113 mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF);
114 }
115
116 static struct bio *
g_bioq_first(struct g_bioq * bq)117 g_bioq_first(struct g_bioq *bq)
118 {
119 struct bio *bp;
120
121 bp = TAILQ_FIRST(&bq->bio_queue);
122 if (bp != NULL) {
123 KASSERT((bp->bio_flags & BIO_ONQUEUE),
124 ("Bio not on queue bp=%p target %p", bp, bq));
125 bp->bio_flags &= ~BIO_ONQUEUE;
126 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue);
127 bq->bio_queue_length--;
128 }
129 return (bp);
130 }
131
132 struct bio *
g_new_bio(void)133 g_new_bio(void)
134 {
135 struct bio *bp;
136
137 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO);
138 #ifdef KTR
139 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
140 struct stack st;
141
142 CTR1(KTR_GEOM, "g_new_bio(): %p", bp);
143 stack_save(&st);
144 CTRSTACK(KTR_GEOM, &st, 3, 0);
145 }
146 #endif
147 return (bp);
148 }
149
150 struct bio *
g_alloc_bio(void)151 g_alloc_bio(void)
152 {
153 struct bio *bp;
154
155 bp = uma_zalloc(biozone, M_WAITOK | M_ZERO);
156 #ifdef KTR
157 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
158 struct stack st;
159
160 CTR1(KTR_GEOM, "g_alloc_bio(): %p", bp);
161 stack_save(&st);
162 CTRSTACK(KTR_GEOM, &st, 3, 0);
163 }
164 #endif
165 return (bp);
166 }
167
168 void
g_destroy_bio(struct bio * bp)169 g_destroy_bio(struct bio *bp)
170 {
171 #ifdef KTR
172 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
173 struct stack st;
174
175 CTR1(KTR_GEOM, "g_destroy_bio(): %p", bp);
176 stack_save(&st);
177 CTRSTACK(KTR_GEOM, &st, 3, 0);
178 }
179 #endif
180 uma_zfree(biozone, bp);
181 }
182
183 struct bio *
g_clone_bio(struct bio * bp)184 g_clone_bio(struct bio *bp)
185 {
186 struct bio *bp2;
187
188 bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO);
189 if (bp2 != NULL) {
190 bp2->bio_parent = bp;
191 bp2->bio_cmd = bp->bio_cmd;
192 /*
193 * BIO_ORDERED flag may be used by disk drivers to enforce
194 * ordering restrictions, so this flag needs to be cloned.
195 * BIO_UNMAPPED should be inherited, to properly indicate
196 * which way the buffer is passed.
197 * Other bio flags are not suitable for cloning.
198 */
199 bp2->bio_flags = bp->bio_flags & (BIO_ORDERED | BIO_UNMAPPED);
200 bp2->bio_length = bp->bio_length;
201 bp2->bio_offset = bp->bio_offset;
202 bp2->bio_data = bp->bio_data;
203 bp2->bio_ma = bp->bio_ma;
204 bp2->bio_ma_n = bp->bio_ma_n;
205 bp2->bio_ma_offset = bp->bio_ma_offset;
206 bp2->bio_attribute = bp->bio_attribute;
207 /* Inherit classification info from the parent */
208 bp2->bio_classifier1 = bp->bio_classifier1;
209 bp2->bio_classifier2 = bp->bio_classifier2;
210 bp->bio_children++;
211 }
212 #ifdef KTR
213 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
214 struct stack st;
215
216 CTR2(KTR_GEOM, "g_clone_bio(%p): %p", bp, bp2);
217 stack_save(&st);
218 CTRSTACK(KTR_GEOM, &st, 3, 0);
219 }
220 #endif
221 return(bp2);
222 }
223
224 struct bio *
g_duplicate_bio(struct bio * bp)225 g_duplicate_bio(struct bio *bp)
226 {
227 struct bio *bp2;
228
229 bp2 = uma_zalloc(biozone, M_WAITOK | M_ZERO);
230 bp2->bio_flags = bp->bio_flags & BIO_UNMAPPED;
231 bp2->bio_parent = bp;
232 bp2->bio_cmd = bp->bio_cmd;
233 bp2->bio_length = bp->bio_length;
234 bp2->bio_offset = bp->bio_offset;
235 bp2->bio_data = bp->bio_data;
236 bp2->bio_ma = bp->bio_ma;
237 bp2->bio_ma_n = bp->bio_ma_n;
238 bp2->bio_ma_offset = bp->bio_ma_offset;
239 bp2->bio_attribute = bp->bio_attribute;
240 bp->bio_children++;
241 #ifdef KTR
242 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
243 struct stack st;
244
245 CTR2(KTR_GEOM, "g_duplicate_bio(%p): %p", bp, bp2);
246 stack_save(&st);
247 CTRSTACK(KTR_GEOM, &st, 3, 0);
248 }
249 #endif
250 return(bp2);
251 }
252
253 void
g_io_init()254 g_io_init()
255 {
256
257 g_bioq_init(&g_bio_run_down);
258 g_bioq_init(&g_bio_run_up);
259 g_bioq_init(&g_bio_run_task);
260 biozone = uma_zcreate("g_bio", sizeof (struct bio),
261 NULL, NULL,
262 NULL, NULL,
263 0, 0);
264 }
265
266 int
g_io_getattr(const char * attr,struct g_consumer * cp,int * len,void * ptr)267 g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr)
268 {
269 struct bio *bp;
270 int error;
271
272 g_trace(G_T_BIO, "bio_getattr(%s)", attr);
273 bp = g_alloc_bio();
274 bp->bio_cmd = BIO_GETATTR;
275 bp->bio_done = NULL;
276 bp->bio_attribute = attr;
277 bp->bio_length = *len;
278 bp->bio_data = ptr;
279 g_io_request(bp, cp);
280 error = biowait(bp, "ggetattr");
281 *len = bp->bio_completed;
282 g_destroy_bio(bp);
283 return (error);
284 }
285
286 int
g_io_flush(struct g_consumer * cp)287 g_io_flush(struct g_consumer *cp)
288 {
289 struct bio *bp;
290 int error;
291
292 g_trace(G_T_BIO, "bio_flush(%s)", cp->provider->name);
293 bp = g_alloc_bio();
294 bp->bio_cmd = BIO_FLUSH;
295 bp->bio_flags |= BIO_ORDERED;
296 bp->bio_done = NULL;
297 bp->bio_attribute = NULL;
298 bp->bio_offset = cp->provider->mediasize;
299 bp->bio_length = 0;
300 bp->bio_data = NULL;
301 g_io_request(bp, cp);
302 error = biowait(bp, "gflush");
303 g_destroy_bio(bp);
304 return (error);
305 }
306
307 static int
g_io_check(struct bio * bp)308 g_io_check(struct bio *bp)
309 {
310 struct g_consumer *cp;
311 struct g_provider *pp;
312
313 cp = bp->bio_from;
314 pp = bp->bio_to;
315
316 /* Fail if access counters dont allow the operation */
317 switch(bp->bio_cmd) {
318 case BIO_READ:
319 case BIO_GETATTR:
320 if (cp->acr == 0)
321 return (EPERM);
322 break;
323 case BIO_WRITE:
324 case BIO_DELETE:
325 case BIO_FLUSH:
326 if (cp->acw == 0)
327 return (EPERM);
328 break;
329 default:
330 return (EPERM);
331 }
332 /* if provider is marked for error, don't disturb. */
333 if (pp->error)
334 return (pp->error);
335 if (cp->flags & G_CF_ORPHAN)
336 return (ENXIO);
337
338 switch(bp->bio_cmd) {
339 case BIO_READ:
340 case BIO_WRITE:
341 case BIO_DELETE:
342 /* Zero sectorsize or mediasize is probably a lack of media. */
343 if (pp->sectorsize == 0 || pp->mediasize == 0)
344 return (ENXIO);
345 /* Reject I/O not on sector boundary */
346 if (bp->bio_offset % pp->sectorsize)
347 return (EINVAL);
348 /* Reject I/O not integral sector long */
349 if (bp->bio_length % pp->sectorsize)
350 return (EINVAL);
351 /* Reject requests before or past the end of media. */
352 if (bp->bio_offset < 0)
353 return (EIO);
354 if (bp->bio_offset > pp->mediasize)
355 return (EIO);
356 break;
357 default:
358 break;
359 }
360 return (0);
361 }
362
363 /*
364 * bio classification support.
365 *
366 * g_register_classifier() and g_unregister_classifier()
367 * are used to add/remove a classifier from the list.
368 * The list is protected using the g_bio_run_down lock,
369 * because the classifiers are called in this path.
370 *
371 * g_io_request() passes bio's that are not already classified
372 * (i.e. those with bio_classifier1 == NULL) to g_run_classifiers().
373 * Classifiers can store their result in the two fields
374 * bio_classifier1 and bio_classifier2.
375 * A classifier that updates one of the fields should
376 * return a non-zero value.
377 * If no classifier updates the field, g_run_classifiers() sets
378 * bio_classifier1 = BIO_NOTCLASSIFIED to avoid further calls.
379 */
380
381 int
g_register_classifier(struct g_classifier_hook * hook)382 g_register_classifier(struct g_classifier_hook *hook)
383 {
384
385 g_bioq_lock(&g_bio_run_down);
386 TAILQ_INSERT_TAIL(&g_classifier_tailq, hook, link);
387 g_bioq_unlock(&g_bio_run_down);
388
389 return (0);
390 }
391
392 void
g_unregister_classifier(struct g_classifier_hook * hook)393 g_unregister_classifier(struct g_classifier_hook *hook)
394 {
395 struct g_classifier_hook *entry;
396
397 g_bioq_lock(&g_bio_run_down);
398 TAILQ_FOREACH(entry, &g_classifier_tailq, link) {
399 if (entry == hook) {
400 TAILQ_REMOVE(&g_classifier_tailq, hook, link);
401 break;
402 }
403 }
404 g_bioq_unlock(&g_bio_run_down);
405 }
406
407 static void
g_run_classifiers(struct bio * bp)408 g_run_classifiers(struct bio *bp)
409 {
410 struct g_classifier_hook *hook;
411 int classified = 0;
412
413 TAILQ_FOREACH(hook, &g_classifier_tailq, link)
414 classified |= hook->func(hook->arg, bp);
415
416 if (!classified)
417 bp->bio_classifier1 = BIO_NOTCLASSIFIED;
418 }
419
420 void
g_io_request(struct bio * bp,struct g_consumer * cp)421 g_io_request(struct bio *bp, struct g_consumer *cp)
422 {
423 struct g_provider *pp;
424 int first;
425
426 KASSERT(cp != NULL, ("NULL cp in g_io_request"));
427 KASSERT(bp != NULL, ("NULL bp in g_io_request"));
428 pp = cp->provider;
429 KASSERT(pp != NULL, ("consumer not attached in g_io_request"));
430 #ifdef DIAGNOSTIC
431 KASSERT(bp->bio_driver1 == NULL,
432 ("bio_driver1 used by the consumer (geom %s)", cp->geom->name));
433 KASSERT(bp->bio_driver2 == NULL,
434 ("bio_driver2 used by the consumer (geom %s)", cp->geom->name));
435 KASSERT(bp->bio_pflags == 0,
436 ("bio_pflags used by the consumer (geom %s)", cp->geom->name));
437 /*
438 * Remember consumer's private fields, so we can detect if they were
439 * modified by the provider.
440 */
441 bp->_bio_caller1 = bp->bio_caller1;
442 bp->_bio_caller2 = bp->bio_caller2;
443 bp->_bio_cflags = bp->bio_cflags;
444 #endif
445
446 if (bp->bio_cmd & (BIO_READ|BIO_WRITE|BIO_GETATTR)) {
447 KASSERT(bp->bio_data != NULL,
448 ("NULL bp->data in g_io_request(cmd=%hhu)", bp->bio_cmd));
449 }
450 if (bp->bio_cmd & (BIO_DELETE|BIO_FLUSH)) {
451 KASSERT(bp->bio_data == NULL,
452 ("non-NULL bp->data in g_io_request(cmd=%hhu)",
453 bp->bio_cmd));
454 }
455 if (bp->bio_cmd & (BIO_READ|BIO_WRITE|BIO_DELETE)) {
456 KASSERT(bp->bio_offset % cp->provider->sectorsize == 0,
457 ("wrong offset %jd for sectorsize %u",
458 bp->bio_offset, cp->provider->sectorsize));
459 KASSERT(bp->bio_length % cp->provider->sectorsize == 0,
460 ("wrong length %jd for sectorsize %u",
461 bp->bio_length, cp->provider->sectorsize));
462 }
463
464 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d",
465 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd);
466
467 bp->bio_from = cp;
468 bp->bio_to = pp;
469 bp->bio_error = 0;
470 bp->bio_completed = 0;
471
472 KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
473 ("Bio already on queue bp=%p", bp));
474 bp->bio_flags |= BIO_ONQUEUE;
475
476 if (g_collectstats)
477 binuptime(&bp->bio_t0);
478 else
479 getbinuptime(&bp->bio_t0);
480
481 /*
482 * The statistics collection is lockless, as such, but we
483 * can not update one instance of the statistics from more
484 * than one thread at a time, so grab the lock first.
485 *
486 * We also use the lock to protect the list of classifiers.
487 */
488 g_bioq_lock(&g_bio_run_down);
489
490 if (!TAILQ_EMPTY(&g_classifier_tailq) && !bp->bio_classifier1)
491 g_run_classifiers(bp);
492
493 if (g_collectstats & 1)
494 devstat_start_transaction(pp->stat, &bp->bio_t0);
495 if (g_collectstats & 2)
496 devstat_start_transaction(cp->stat, &bp->bio_t0);
497
498 pp->nstart++;
499 cp->nstart++;
500 first = TAILQ_EMPTY(&g_bio_run_down.bio_queue);
501 TAILQ_INSERT_TAIL(&g_bio_run_down.bio_queue, bp, bio_queue);
502 g_bio_run_down.bio_queue_length++;
503 g_bioq_unlock(&g_bio_run_down);
504
505 /* Pass it on down. */
506 if (first)
507 wakeup(&g_wait_down);
508 }
509
510 void
g_io_deliver(struct bio * bp,int error)511 g_io_deliver(struct bio *bp, int error)
512 {
513 struct bintime now;
514 struct g_consumer *cp;
515 struct g_provider *pp;
516 int first;
517
518 KASSERT(bp != NULL, ("NULL bp in g_io_deliver"));
519 pp = bp->bio_to;
520 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver"));
521 cp = bp->bio_from;
522 if (cp == NULL) {
523 bp->bio_error = error;
524 bp->bio_done(bp);
525 return;
526 }
527 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver"));
528 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver"));
529 #ifdef DIAGNOSTIC
530 /*
531 * Some classes - GJournal in particular - can modify bio's
532 * private fields while the bio is in transit; G_GEOM_VOLATILE_BIO
533 * flag means it's an expected behaviour for that particular geom.
534 */
535 if ((cp->geom->flags & G_GEOM_VOLATILE_BIO) == 0) {
536 KASSERT(bp->bio_caller1 == bp->_bio_caller1,
537 ("bio_caller1 used by the provider %s", pp->name));
538 KASSERT(bp->bio_caller2 == bp->_bio_caller2,
539 ("bio_caller2 used by the provider %s", pp->name));
540 KASSERT(bp->bio_cflags == bp->_bio_cflags,
541 ("bio_cflags used by the provider %s", pp->name));
542 }
543 #endif
544 KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0"));
545 KASSERT(bp->bio_completed <= bp->bio_length,
546 ("bio_completed can't be greater than bio_length"));
547
548 g_trace(G_T_BIO,
549 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd",
550 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error,
551 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length);
552
553 KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
554 ("Bio already on queue bp=%p", bp));
555
556 /*
557 * XXX: next two doesn't belong here
558 */
559 bp->bio_bcount = bp->bio_length;
560 bp->bio_resid = bp->bio_bcount - bp->bio_completed;
561
562 /*
563 * The statistics collection is lockless, as such, but we
564 * can not update one instance of the statistics from more
565 * than one thread at a time, so grab the lock first.
566 */
567 if (g_collectstats)
568 binuptime(&now);
569 g_bioq_lock(&g_bio_run_up);
570 if (g_collectstats & 1)
571 devstat_end_transaction_bio_bt(pp->stat, bp, &now);
572 if (g_collectstats & 2)
573 devstat_end_transaction_bio_bt(cp->stat, bp, &now);
574
575 cp->nend++;
576 pp->nend++;
577 if (error != ENOMEM) {
578 bp->bio_error = error;
579 first = TAILQ_EMPTY(&g_bio_run_up.bio_queue);
580 TAILQ_INSERT_TAIL(&g_bio_run_up.bio_queue, bp, bio_queue);
581 bp->bio_flags |= BIO_ONQUEUE;
582 g_bio_run_up.bio_queue_length++;
583 g_bioq_unlock(&g_bio_run_up);
584 if (first)
585 wakeup(&g_wait_up);
586 return;
587 }
588 g_bioq_unlock(&g_bio_run_up);
589
590 if (bootverbose)
591 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name);
592 bp->bio_children = 0;
593 bp->bio_inbed = 0;
594 bp->bio_driver1 = NULL;
595 bp->bio_driver2 = NULL;
596 bp->bio_pflags = 0;
597 g_io_request(bp, cp);
598 pace++;
599 return;
600 }
601
602 SYSCTL_DECL(_kern_geom);
603
604 static long transient_maps;
605 SYSCTL_LONG(_kern_geom, OID_AUTO, transient_maps, CTLFLAG_RD,
606 &transient_maps, 0,
607 "Total count of the transient mapping requests");
608 u_int transient_map_retries = 10;
609 SYSCTL_UINT(_kern_geom, OID_AUTO, transient_map_retries, CTLFLAG_RW,
610 &transient_map_retries, 0,
611 "Max count of retries used before giving up on creating transient map");
612 int transient_map_hard_failures;
613 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_hard_failures, CTLFLAG_RD,
614 &transient_map_hard_failures, 0,
615 "Failures to establish the transient mapping due to retry attempts "
616 "exhausted");
617 int transient_map_soft_failures;
618 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_soft_failures, CTLFLAG_RD,
619 &transient_map_soft_failures, 0,
620 "Count of retried failures to establish the transient mapping");
621 int inflight_transient_maps;
622 SYSCTL_INT(_kern_geom, OID_AUTO, inflight_transient_maps, CTLFLAG_RD,
623 &inflight_transient_maps, 0,
624 "Current count of the active transient maps");
625
626 static int
g_io_transient_map_bio(struct bio * bp)627 g_io_transient_map_bio(struct bio *bp)
628 {
629 vm_offset_t addr;
630 long size;
631 u_int retried;
632 int rv;
633
634 KASSERT(unmapped_buf_allowed, ("unmapped disabled"));
635
636 size = round_page(bp->bio_ma_offset + bp->bio_length);
637 KASSERT(size / PAGE_SIZE == bp->bio_ma_n, ("Bio too short %p", bp));
638 addr = 0;
639 retried = 0;
640 atomic_add_long(&transient_maps, 1);
641 retry:
642 vm_map_lock(bio_transient_map);
643 if (vm_map_findspace(bio_transient_map, vm_map_min(bio_transient_map),
644 size, &addr)) {
645 vm_map_unlock(bio_transient_map);
646 if (transient_map_retries != 0 &&
647 retried >= transient_map_retries) {
648 g_io_deliver(bp, EDEADLK/* XXXKIB */);
649 CTR2(KTR_GEOM, "g_down cannot map bp %p provider %s",
650 bp, bp->bio_to->name);
651 atomic_add_int(&transient_map_hard_failures, 1);
652 return (1);
653 } else {
654 /*
655 * Naive attempt to quisce the I/O to get more
656 * in-flight requests completed and defragment
657 * the bio_transient_map.
658 */
659 CTR3(KTR_GEOM, "g_down retrymap bp %p provider %s r %d",
660 bp, bp->bio_to->name, retried);
661 pause("g_d_tra", hz / 10);
662 retried++;
663 atomic_add_int(&transient_map_soft_failures, 1);
664 goto retry;
665 }
666 }
667 rv = vm_map_insert(bio_transient_map, NULL, 0, addr, addr + size,
668 VM_PROT_RW, VM_PROT_RW, MAP_NOFAULT);
669 KASSERT(rv == KERN_SUCCESS,
670 ("vm_map_insert(bio_transient_map) rv %d %jx %lx",
671 rv, (uintmax_t)addr, size));
672 vm_map_unlock(bio_transient_map);
673 atomic_add_int(&inflight_transient_maps, 1);
674 pmap_qenter((vm_offset_t)addr, bp->bio_ma, OFF_TO_IDX(size));
675 bp->bio_data = (caddr_t)addr + bp->bio_ma_offset;
676 bp->bio_flags |= BIO_TRANSIENT_MAPPING;
677 bp->bio_flags &= ~BIO_UNMAPPED;
678 return (0);
679 }
680
681 void
g_io_schedule_down(struct thread * tp __unused)682 g_io_schedule_down(struct thread *tp __unused)
683 {
684 struct bio *bp;
685 off_t excess;
686 int error;
687
688 for(;;) {
689 g_bioq_lock(&g_bio_run_down);
690 bp = g_bioq_first(&g_bio_run_down);
691 if (bp == NULL) {
692 CTR0(KTR_GEOM, "g_down going to sleep");
693 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock,
694 PRIBIO | PDROP, "-", 0);
695 continue;
696 }
697 CTR0(KTR_GEOM, "g_down has work to do");
698 g_bioq_unlock(&g_bio_run_down);
699 if (pace > 0) {
700 CTR1(KTR_GEOM, "g_down pacing self (pace %d)", pace);
701 pause("g_down", hz/10);
702 pace--;
703 }
704 error = g_io_check(bp);
705 if (error) {
706 CTR3(KTR_GEOM, "g_down g_io_check on bp %p provider "
707 "%s returned %d", bp, bp->bio_to->name, error);
708 g_io_deliver(bp, error);
709 continue;
710 }
711 CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp,
712 bp->bio_to->name);
713 switch (bp->bio_cmd) {
714 case BIO_READ:
715 case BIO_WRITE:
716 case BIO_DELETE:
717 /* Truncate requests to the end of providers media. */
718 /*
719 * XXX: What if we truncate because of offset being
720 * bad, not length?
721 */
722 excess = bp->bio_offset + bp->bio_length;
723 if (excess > bp->bio_to->mediasize) {
724 KASSERT((bp->bio_flags & BIO_UNMAPPED) == 0 ||
725 round_page(bp->bio_ma_offset +
726 bp->bio_length) / PAGE_SIZE == bp->bio_ma_n,
727 ("excess bio %p too short", bp));
728 excess -= bp->bio_to->mediasize;
729 bp->bio_length -= excess;
730 if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
731 bp->bio_ma_n = round_page(
732 bp->bio_ma_offset +
733 bp->bio_length) / PAGE_SIZE;
734 }
735 if (excess > 0)
736 CTR3(KTR_GEOM, "g_down truncated bio "
737 "%p provider %s by %d", bp,
738 bp->bio_to->name, excess);
739 }
740 /* Deliver zero length transfers right here. */
741 if (bp->bio_length == 0) {
742 g_io_deliver(bp, 0);
743 CTR2(KTR_GEOM, "g_down terminated 0-length "
744 "bp %p provider %s", bp, bp->bio_to->name);
745 continue;
746 }
747 break;
748 default:
749 break;
750 }
751 if ((bp->bio_flags & BIO_UNMAPPED) != 0 &&
752 (bp->bio_to->flags & G_PF_ACCEPT_UNMAPPED) == 0 &&
753 (bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE)) {
754 if (g_io_transient_map_bio(bp))
755 continue;
756 }
757 THREAD_NO_SLEEPING();
758 CTR4(KTR_GEOM, "g_down starting bp %p provider %s off %ld "
759 "len %ld", bp, bp->bio_to->name, bp->bio_offset,
760 bp->bio_length);
761 bp->bio_to->geom->start(bp);
762 THREAD_SLEEPING_OK();
763 }
764 }
765
766 void
bio_taskqueue(struct bio * bp,bio_task_t * func,void * arg)767 bio_taskqueue(struct bio *bp, bio_task_t *func, void *arg)
768 {
769 bp->bio_task = func;
770 bp->bio_task_arg = arg;
771 /*
772 * The taskqueue is actually just a second queue off the "up"
773 * queue, so we use the same lock.
774 */
775 g_bioq_lock(&g_bio_run_up);
776 KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
777 ("Bio already on queue bp=%p target taskq", bp));
778 bp->bio_flags |= BIO_ONQUEUE;
779 TAILQ_INSERT_TAIL(&g_bio_run_task.bio_queue, bp, bio_queue);
780 g_bio_run_task.bio_queue_length++;
781 wakeup(&g_wait_up);
782 g_bioq_unlock(&g_bio_run_up);
783 }
784
785
786 void
g_io_schedule_up(struct thread * tp __unused)787 g_io_schedule_up(struct thread *tp __unused)
788 {
789 struct bio *bp;
790 for(;;) {
791 g_bioq_lock(&g_bio_run_up);
792 bp = g_bioq_first(&g_bio_run_task);
793 if (bp != NULL) {
794 g_bioq_unlock(&g_bio_run_up);
795 THREAD_NO_SLEEPING();
796 CTR1(KTR_GEOM, "g_up processing task bp %p", bp);
797 bp->bio_task(bp->bio_task_arg);
798 THREAD_SLEEPING_OK();
799 continue;
800 }
801 bp = g_bioq_first(&g_bio_run_up);
802 if (bp != NULL) {
803 g_bioq_unlock(&g_bio_run_up);
804 THREAD_NO_SLEEPING();
805 CTR4(KTR_GEOM, "g_up biodone bp %p provider %s off "
806 "%jd len %ld", bp, bp->bio_to->name,
807 bp->bio_offset, bp->bio_length);
808 biodone(bp);
809 THREAD_SLEEPING_OK();
810 continue;
811 }
812 CTR0(KTR_GEOM, "g_up going to sleep");
813 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock,
814 PRIBIO | PDROP, "-", 0);
815 }
816 }
817
818 void *
g_read_data(struct g_consumer * cp,off_t offset,off_t length,int * error)819 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error)
820 {
821 struct bio *bp;
822 void *ptr;
823 int errorc;
824
825 KASSERT(length > 0 && length >= cp->provider->sectorsize &&
826 length <= MAXPHYS, ("g_read_data(): invalid length %jd",
827 (intmax_t)length));
828
829 bp = g_alloc_bio();
830 bp->bio_cmd = BIO_READ;
831 bp->bio_done = NULL;
832 bp->bio_offset = offset;
833 bp->bio_length = length;
834 ptr = g_malloc(length, M_WAITOK);
835 bp->bio_data = ptr;
836 g_io_request(bp, cp);
837 errorc = biowait(bp, "gread");
838 if (error != NULL)
839 *error = errorc;
840 g_destroy_bio(bp);
841 if (errorc) {
842 g_free(ptr);
843 ptr = NULL;
844 }
845 return (ptr);
846 }
847
848 int
g_write_data(struct g_consumer * cp,off_t offset,void * ptr,off_t length)849 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length)
850 {
851 struct bio *bp;
852 int error;
853
854 KASSERT(length > 0 && length >= cp->provider->sectorsize &&
855 length <= MAXPHYS, ("g_write_data(): invalid length %jd",
856 (intmax_t)length));
857
858 bp = g_alloc_bio();
859 bp->bio_cmd = BIO_WRITE;
860 bp->bio_done = NULL;
861 bp->bio_offset = offset;
862 bp->bio_length = length;
863 bp->bio_data = ptr;
864 g_io_request(bp, cp);
865 error = biowait(bp, "gwrite");
866 g_destroy_bio(bp);
867 return (error);
868 }
869
870 int
g_delete_data(struct g_consumer * cp,off_t offset,off_t length)871 g_delete_data(struct g_consumer *cp, off_t offset, off_t length)
872 {
873 struct bio *bp;
874 int error;
875
876 KASSERT(length > 0 && length >= cp->provider->sectorsize,
877 ("g_delete_data(): invalid length %jd", (intmax_t)length));
878
879 bp = g_alloc_bio();
880 bp->bio_cmd = BIO_DELETE;
881 bp->bio_done = NULL;
882 bp->bio_offset = offset;
883 bp->bio_length = length;
884 bp->bio_data = NULL;
885 g_io_request(bp, cp);
886 error = biowait(bp, "gdelete");
887 g_destroy_bio(bp);
888 return (error);
889 }
890
891 void
g_print_bio(struct bio * bp)892 g_print_bio(struct bio *bp)
893 {
894 const char *pname, *cmd = NULL;
895
896 if (bp->bio_to != NULL)
897 pname = bp->bio_to->name;
898 else
899 pname = "[unknown]";
900
901 switch (bp->bio_cmd) {
902 case BIO_GETATTR:
903 cmd = "GETATTR";
904 printf("%s[%s(attr=%s)]", pname, cmd, bp->bio_attribute);
905 return;
906 case BIO_FLUSH:
907 cmd = "FLUSH";
908 printf("%s[%s]", pname, cmd);
909 return;
910 case BIO_READ:
911 cmd = "READ";
912 break;
913 case BIO_WRITE:
914 cmd = "WRITE";
915 break;
916 case BIO_DELETE:
917 cmd = "DELETE";
918 break;
919 default:
920 cmd = "UNKNOWN";
921 printf("%s[%s()]", pname, cmd);
922 return;
923 }
924 printf("%s[%s(offset=%jd, length=%jd)]", pname, cmd,
925 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length);
926 }
927