FreeBSD/Linux Kernel Cross Reference
sys/geom/geom_io.c
1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2002 Poul-Henning Kamp
5 * Copyright (c) 2002 Networks Associates Technology, Inc.
6 * Copyright (c) 2013 The FreeBSD Foundation
7 * All rights reserved.
8 *
9 * This software was developed for the FreeBSD Project by Poul-Henning Kamp
10 * and NAI Labs, the Security Research Division of Network Associates, Inc.
11 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
12 * DARPA CHATS research program.
13 *
14 * Portions of this software were developed by Konstantin Belousov
15 * under sponsorship from the FreeBSD Foundation.
16 *
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
19 * are met:
20 * 1. Redistributions of source code must retain the above copyright
21 * notice, this list of conditions and the following disclaimer.
22 * 2. Redistributions in binary form must reproduce the above copyright
23 * notice, this list of conditions and the following disclaimer in the
24 * documentation and/or other materials provided with the distribution.
25 * 3. The names of the authors may not be used to endorse or promote
26 * products derived from this software without specific prior written
27 * permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * SUCH DAMAGE.
40 */
41
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
44
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/kernel.h>
48 #include <sys/malloc.h>
49 #include <sys/bio.h>
50 #include <sys/ktr.h>
51 #include <sys/proc.h>
52 #include <sys/sbuf.h>
53 #include <sys/stack.h>
54 #include <sys/sysctl.h>
55 #include <sys/vmem.h>
56 #include <machine/stdarg.h>
57
58 #include <sys/errno.h>
59 #include <geom/geom.h>
60 #include <geom/geom_int.h>
61 #include <sys/devicestat.h>
62
63 #include <vm/uma.h>
64 #include <vm/vm.h>
65 #include <vm/vm_param.h>
66 #include <vm/vm_kern.h>
67 #include <vm/vm_page.h>
68 #include <vm/vm_object.h>
69 #include <vm/vm_extern.h>
70 #include <vm/vm_map.h>
71
72 static int g_io_transient_map_bio(struct bio *bp);
73
74 static struct g_bioq g_bio_run_down;
75 static struct g_bioq g_bio_run_up;
76
77 /*
78 * Pace is a hint that we've had some trouble recently allocating
79 * bios, so we should back off trying to send I/O down the stack
80 * a bit to let the problem resolve. When pacing, we also turn
81 * off direct dispatch to also reduce memory pressure from I/Os
82 * there, at the expxense of some added latency while the memory
83 * pressures exist. See g_io_schedule_down() for more details
84 * and limitations.
85 */
86 static volatile u_int __read_mostly pace;
87
88 static uma_zone_t __read_mostly biozone;
89
90 #include <machine/atomic.h>
91
92 static void
93 g_bioq_lock(struct g_bioq *bq)
94 {
95
96 mtx_lock(&bq->bio_queue_lock);
97 }
98
99 static void
100 g_bioq_unlock(struct g_bioq *bq)
101 {
102
103 mtx_unlock(&bq->bio_queue_lock);
104 }
105
106 #if 0
107 static void
108 g_bioq_destroy(struct g_bioq *bq)
109 {
110
111 mtx_destroy(&bq->bio_queue_lock);
112 }
113 #endif
114
115 static void
116 g_bioq_init(struct g_bioq *bq)
117 {
118
119 TAILQ_INIT(&bq->bio_queue);
120 mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF);
121 }
122
123 static struct bio *
124 g_bioq_first(struct g_bioq *bq)
125 {
126 struct bio *bp;
127
128 bp = TAILQ_FIRST(&bq->bio_queue);
129 if (bp != NULL) {
130 KASSERT((bp->bio_flags & BIO_ONQUEUE),
131 ("Bio not on queue bp=%p target %p", bp, bq));
132 bp->bio_flags &= ~BIO_ONQUEUE;
133 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue);
134 bq->bio_queue_length--;
135 }
136 return (bp);
137 }
138
139 struct bio *
140 g_new_bio(void)
141 {
142 struct bio *bp;
143
144 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO);
145 #ifdef KTR
146 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
147 struct stack st;
148
149 CTR1(KTR_GEOM, "g_new_bio(): %p", bp);
150 stack_save(&st);
151 CTRSTACK(KTR_GEOM, &st, 3);
152 }
153 #endif
154 return (bp);
155 }
156
157 struct bio *
158 g_alloc_bio(void)
159 {
160 struct bio *bp;
161
162 bp = uma_zalloc(biozone, M_WAITOK | M_ZERO);
163 #ifdef KTR
164 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
165 struct stack st;
166
167 CTR1(KTR_GEOM, "g_alloc_bio(): %p", bp);
168 stack_save(&st);
169 CTRSTACK(KTR_GEOM, &st, 3);
170 }
171 #endif
172 return (bp);
173 }
174
175 void
176 g_destroy_bio(struct bio *bp)
177 {
178 #ifdef KTR
179 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
180 struct stack st;
181
182 CTR1(KTR_GEOM, "g_destroy_bio(): %p", bp);
183 stack_save(&st);
184 CTRSTACK(KTR_GEOM, &st, 3);
185 }
186 #endif
187 uma_zfree(biozone, bp);
188 }
189
190 struct bio *
191 g_clone_bio(struct bio *bp)
192 {
193 struct bio *bp2;
194
195 bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO);
196 if (bp2 != NULL) {
197 bp2->bio_parent = bp;
198 bp2->bio_cmd = bp->bio_cmd;
199 /*
200 * BIO_ORDERED flag may be used by disk drivers to enforce
201 * ordering restrictions, so this flag needs to be cloned.
202 * BIO_UNMAPPED, BIO_VLIST, and BIO_SWAP should be inherited,
203 * to properly indicate which way the buffer is passed.
204 * Other bio flags are not suitable for cloning.
205 */
206 bp2->bio_flags = bp->bio_flags &
207 (BIO_ORDERED | BIO_UNMAPPED | BIO_VLIST | BIO_SWAP);
208 bp2->bio_length = bp->bio_length;
209 bp2->bio_offset = bp->bio_offset;
210 bp2->bio_data = bp->bio_data;
211 bp2->bio_ma = bp->bio_ma;
212 bp2->bio_ma_n = bp->bio_ma_n;
213 bp2->bio_ma_offset = bp->bio_ma_offset;
214 bp2->bio_attribute = bp->bio_attribute;
215 if (bp->bio_cmd == BIO_ZONE)
216 bcopy(&bp->bio_zone, &bp2->bio_zone,
217 sizeof(bp->bio_zone));
218 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING)
219 bp2->bio_track_bp = bp->bio_track_bp;
220 #endif
221 bp->bio_children++;
222 }
223 #ifdef KTR
224 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
225 struct stack st;
226
227 CTR2(KTR_GEOM, "g_clone_bio(%p): %p", bp, bp2);
228 stack_save(&st);
229 CTRSTACK(KTR_GEOM, &st, 3);
230 }
231 #endif
232 return(bp2);
233 }
234
235 struct bio *
236 g_duplicate_bio(struct bio *bp)
237 {
238 struct bio *bp2;
239
240 bp2 = uma_zalloc(biozone, M_WAITOK | M_ZERO);
241 bp2->bio_flags = bp->bio_flags & (BIO_UNMAPPED | BIO_VLIST | BIO_SWAP);
242 bp2->bio_parent = bp;
243 bp2->bio_cmd = bp->bio_cmd;
244 bp2->bio_length = bp->bio_length;
245 bp2->bio_offset = bp->bio_offset;
246 bp2->bio_data = bp->bio_data;
247 bp2->bio_ma = bp->bio_ma;
248 bp2->bio_ma_n = bp->bio_ma_n;
249 bp2->bio_ma_offset = bp->bio_ma_offset;
250 bp2->bio_attribute = bp->bio_attribute;
251 bp->bio_children++;
252 #ifdef KTR
253 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
254 struct stack st;
255
256 CTR2(KTR_GEOM, "g_duplicate_bio(%p): %p", bp, bp2);
257 stack_save(&st);
258 CTRSTACK(KTR_GEOM, &st, 3);
259 }
260 #endif
261 return(bp2);
262 }
263
264 void
265 g_reset_bio(struct bio *bp)
266 {
267
268 bzero(bp, sizeof(*bp));
269 }
270
271 void
272 g_io_init(void)
273 {
274
275 g_bioq_init(&g_bio_run_down);
276 g_bioq_init(&g_bio_run_up);
277 biozone = uma_zcreate("g_bio", sizeof (struct bio),
278 NULL, NULL,
279 NULL, NULL,
280 0, 0);
281 }
282
283 int
284 g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr)
285 {
286 struct bio *bp;
287 int error;
288
289 g_trace(G_T_BIO, "bio_getattr(%s)", attr);
290 bp = g_alloc_bio();
291 bp->bio_cmd = BIO_GETATTR;
292 bp->bio_done = NULL;
293 bp->bio_attribute = attr;
294 bp->bio_length = *len;
295 bp->bio_data = ptr;
296 g_io_request(bp, cp);
297 error = biowait(bp, "ggetattr");
298 *len = bp->bio_completed;
299 g_destroy_bio(bp);
300 return (error);
301 }
302
303 int
304 g_io_zonecmd(struct disk_zone_args *zone_args, struct g_consumer *cp)
305 {
306 struct bio *bp;
307 int error;
308
309 g_trace(G_T_BIO, "bio_zone(%d)", zone_args->zone_cmd);
310 bp = g_alloc_bio();
311 bp->bio_cmd = BIO_ZONE;
312 bp->bio_done = NULL;
313 /*
314 * XXX KDM need to handle report zone data.
315 */
316 bcopy(zone_args, &bp->bio_zone, sizeof(*zone_args));
317 if (zone_args->zone_cmd == DISK_ZONE_REPORT_ZONES)
318 bp->bio_length =
319 zone_args->zone_params.report.entries_allocated *
320 sizeof(struct disk_zone_rep_entry);
321 else
322 bp->bio_length = 0;
323
324 g_io_request(bp, cp);
325 error = biowait(bp, "gzone");
326 bcopy(&bp->bio_zone, zone_args, sizeof(*zone_args));
327 g_destroy_bio(bp);
328 return (error);
329 }
330
331 /*
332 * Send a BIO_SPEEDUP down the stack. This is used to tell the lower layers that
333 * the upper layers have detected a resource shortage. The lower layers are
334 * advised to stop delaying I/O that they might be holding for performance
335 * reasons and to schedule it (non-trims) or complete it successfully (trims) as
336 * quickly as it can. bio_length is the amount of the shortage. This call
337 * should be non-blocking. bio_resid is used to communicate back if the lower
338 * layers couldn't find bio_length worth of I/O to schedule or discard. A length
339 * of 0 means to do as much as you can (schedule the h/w queues full, discard
340 * all trims). flags are a hint from the upper layers to the lower layers what
341 * operation should be done.
342 */
343 int
344 g_io_speedup(off_t shortage, u_int flags, size_t *resid, struct g_consumer *cp)
345 {
346 struct bio *bp;
347 int error;
348
349 KASSERT((flags & (BIO_SPEEDUP_TRIM | BIO_SPEEDUP_WRITE)) != 0,
350 ("Invalid flags passed to g_io_speedup: %#x", flags));
351 g_trace(G_T_BIO, "bio_speedup(%s, %jd, %#x)", cp->provider->name,
352 (intmax_t)shortage, flags);
353 bp = g_new_bio();
354 if (bp == NULL)
355 return (ENOMEM);
356 bp->bio_cmd = BIO_SPEEDUP;
357 bp->bio_length = shortage;
358 bp->bio_done = NULL;
359 bp->bio_flags |= flags;
360 g_io_request(bp, cp);
361 error = biowait(bp, "gflush");
362 *resid = bp->bio_resid;
363 g_destroy_bio(bp);
364 return (error);
365 }
366
367 int
368 g_io_flush(struct g_consumer *cp)
369 {
370 struct bio *bp;
371 int error;
372
373 g_trace(G_T_BIO, "bio_flush(%s)", cp->provider->name);
374 bp = g_alloc_bio();
375 bp->bio_cmd = BIO_FLUSH;
376 bp->bio_flags |= BIO_ORDERED;
377 bp->bio_done = NULL;
378 bp->bio_attribute = NULL;
379 bp->bio_offset = cp->provider->mediasize;
380 bp->bio_length = 0;
381 bp->bio_data = NULL;
382 g_io_request(bp, cp);
383 error = biowait(bp, "gflush");
384 g_destroy_bio(bp);
385 return (error);
386 }
387
388 static int
389 g_io_check(struct bio *bp)
390 {
391 struct g_consumer *cp;
392 struct g_provider *pp;
393 off_t excess;
394 int error;
395
396 biotrack(bp, __func__);
397
398 cp = bp->bio_from;
399 pp = bp->bio_to;
400
401 /* Fail if access counters dont allow the operation */
402 switch(bp->bio_cmd) {
403 case BIO_READ:
404 case BIO_GETATTR:
405 if (cp->acr == 0)
406 return (EPERM);
407 break;
408 case BIO_WRITE:
409 case BIO_DELETE:
410 case BIO_SPEEDUP:
411 case BIO_FLUSH:
412 if (cp->acw == 0)
413 return (EPERM);
414 break;
415 case BIO_ZONE:
416 if ((bp->bio_zone.zone_cmd == DISK_ZONE_REPORT_ZONES) ||
417 (bp->bio_zone.zone_cmd == DISK_ZONE_GET_PARAMS)) {
418 if (cp->acr == 0)
419 return (EPERM);
420 } else if (cp->acw == 0)
421 return (EPERM);
422 break;
423 default:
424 return (EPERM);
425 }
426 /* if provider is marked for error, don't disturb. */
427 if (pp->error)
428 return (pp->error);
429 if (cp->flags & G_CF_ORPHAN)
430 return (ENXIO);
431
432 switch(bp->bio_cmd) {
433 case BIO_READ:
434 case BIO_WRITE:
435 case BIO_DELETE:
436 /* Zero sectorsize or mediasize is probably a lack of media. */
437 if (pp->sectorsize == 0 || pp->mediasize == 0)
438 return (ENXIO);
439 /* Reject I/O not on sector boundary */
440 if (bp->bio_offset % pp->sectorsize)
441 return (EINVAL);
442 /* Reject I/O not integral sector long */
443 if (bp->bio_length % pp->sectorsize)
444 return (EINVAL);
445 /* Reject requests before or past the end of media. */
446 if (bp->bio_offset < 0)
447 return (EIO);
448 if (bp->bio_offset > pp->mediasize)
449 return (EIO);
450
451 /* Truncate requests to the end of providers media. */
452 excess = bp->bio_offset + bp->bio_length;
453 if (excess > bp->bio_to->mediasize) {
454 KASSERT((bp->bio_flags & BIO_UNMAPPED) == 0 ||
455 round_page(bp->bio_ma_offset +
456 bp->bio_length) / PAGE_SIZE == bp->bio_ma_n,
457 ("excess bio %p too short", bp));
458 excess -= bp->bio_to->mediasize;
459 bp->bio_length -= excess;
460 if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
461 bp->bio_ma_n = round_page(bp->bio_ma_offset +
462 bp->bio_length) / PAGE_SIZE;
463 }
464 if (excess > 0)
465 CTR3(KTR_GEOM, "g_down truncated bio "
466 "%p provider %s by %d", bp,
467 bp->bio_to->name, excess);
468 }
469
470 /* Deliver zero length transfers right here. */
471 if (bp->bio_length == 0) {
472 CTR2(KTR_GEOM, "g_down terminated 0-length "
473 "bp %p provider %s", bp, bp->bio_to->name);
474 return (0);
475 }
476
477 if ((bp->bio_flags & BIO_UNMAPPED) != 0 &&
478 (bp->bio_to->flags & G_PF_ACCEPT_UNMAPPED) == 0 &&
479 (bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE)) {
480 if ((error = g_io_transient_map_bio(bp)) >= 0)
481 return (error);
482 }
483 break;
484 default:
485 break;
486 }
487 return (EJUSTRETURN);
488 }
489
490 void
491 g_io_request(struct bio *bp, struct g_consumer *cp)
492 {
493 struct g_provider *pp;
494 int direct, error, first;
495 uint8_t cmd;
496
497 biotrack(bp, __func__);
498
499 KASSERT(cp != NULL, ("NULL cp in g_io_request"));
500 KASSERT(bp != NULL, ("NULL bp in g_io_request"));
501 pp = cp->provider;
502 KASSERT(pp != NULL, ("consumer not attached in g_io_request"));
503 #ifdef DIAGNOSTIC
504 KASSERT(bp->bio_driver1 == NULL,
505 ("bio_driver1 used by the consumer (geom %s)", cp->geom->name));
506 KASSERT(bp->bio_driver2 == NULL,
507 ("bio_driver2 used by the consumer (geom %s)", cp->geom->name));
508 KASSERT(bp->bio_pflags == 0,
509 ("bio_pflags used by the consumer (geom %s)", cp->geom->name));
510 /*
511 * Remember consumer's private fields, so we can detect if they were
512 * modified by the provider.
513 */
514 bp->_bio_caller1 = bp->bio_caller1;
515 bp->_bio_caller2 = bp->bio_caller2;
516 bp->_bio_cflags = bp->bio_cflags;
517 #endif
518
519 cmd = bp->bio_cmd;
520 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_GETATTR) {
521 KASSERT(bp->bio_data != NULL,
522 ("NULL bp->data in g_io_request(cmd=%hu)", bp->bio_cmd));
523 }
524 if (cmd == BIO_DELETE || cmd == BIO_FLUSH || cmd == BIO_SPEEDUP) {
525 KASSERT(bp->bio_data == NULL,
526 ("non-NULL bp->data in g_io_request(cmd=%hu)",
527 bp->bio_cmd));
528 }
529 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_DELETE) {
530 KASSERT(bp->bio_offset % cp->provider->sectorsize == 0,
531 ("wrong offset %jd for sectorsize %u",
532 bp->bio_offset, cp->provider->sectorsize));
533 KASSERT(bp->bio_length % cp->provider->sectorsize == 0,
534 ("wrong length %jd for sectorsize %u",
535 bp->bio_length, cp->provider->sectorsize));
536 }
537
538 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d",
539 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd);
540
541 bp->bio_from = cp;
542 bp->bio_to = pp;
543 bp->bio_error = 0;
544 bp->bio_completed = 0;
545
546 KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
547 ("Bio already on queue bp=%p", bp));
548
549 if ((g_collectstats & G_STATS_CONSUMERS) != 0 ||
550 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL))
551 binuptime(&bp->bio_t0);
552 else
553 getbinuptime(&bp->bio_t0);
554 if (g_collectstats & G_STATS_CONSUMERS)
555 devstat_start_transaction_bio_t0(cp->stat, bp);
556 if (g_collectstats & G_STATS_PROVIDERS)
557 devstat_start_transaction_bio_t0(pp->stat, bp);
558 #ifdef INVARIANTS
559 atomic_add_int(&cp->nstart, 1);
560 #endif
561
562 direct = (cp->flags & G_CF_DIRECT_SEND) != 0 &&
563 (pp->flags & G_PF_DIRECT_RECEIVE) != 0 &&
564 curthread != g_down_td &&
565 ((pp->flags & G_PF_ACCEPT_UNMAPPED) != 0 ||
566 (bp->bio_flags & BIO_UNMAPPED) == 0 || THREAD_CAN_SLEEP()) &&
567 pace == 0;
568 if (direct) {
569 /* Block direct execution if less then half of stack left. */
570 size_t st, su;
571 GET_STACK_USAGE(st, su);
572 if (su * 2 > st)
573 direct = 0;
574 }
575
576 if (direct) {
577 error = g_io_check(bp);
578 if (error >= 0) {
579 CTR3(KTR_GEOM, "g_io_request g_io_check on bp %p "
580 "provider %s returned %d", bp, bp->bio_to->name,
581 error);
582 g_io_deliver(bp, error);
583 return;
584 }
585 bp->bio_to->geom->start(bp);
586 } else {
587 g_bioq_lock(&g_bio_run_down);
588 first = TAILQ_EMPTY(&g_bio_run_down.bio_queue);
589 TAILQ_INSERT_TAIL(&g_bio_run_down.bio_queue, bp, bio_queue);
590 bp->bio_flags |= BIO_ONQUEUE;
591 g_bio_run_down.bio_queue_length++;
592 g_bioq_unlock(&g_bio_run_down);
593 /* Pass it on down. */
594 if (first)
595 wakeup(&g_wait_down);
596 }
597 }
598
599 void
600 g_io_deliver(struct bio *bp, int error)
601 {
602 struct bintime now;
603 struct g_consumer *cp;
604 struct g_provider *pp;
605 struct mtx *mtxp;
606 int direct, first;
607
608 biotrack(bp, __func__);
609
610 KASSERT(bp != NULL, ("NULL bp in g_io_deliver"));
611 pp = bp->bio_to;
612 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver"));
613 cp = bp->bio_from;
614 if (cp == NULL) {
615 bp->bio_error = error;
616 bp->bio_done(bp);
617 return;
618 }
619 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver"));
620 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver"));
621 #ifdef DIAGNOSTIC
622 /*
623 * Some classes - GJournal in particular - can modify bio's
624 * private fields while the bio is in transit; G_GEOM_VOLATILE_BIO
625 * flag means it's an expected behaviour for that particular geom.
626 */
627 if ((cp->geom->flags & G_GEOM_VOLATILE_BIO) == 0) {
628 KASSERT(bp->bio_caller1 == bp->_bio_caller1,
629 ("bio_caller1 used by the provider %s", pp->name));
630 KASSERT(bp->bio_caller2 == bp->_bio_caller2,
631 ("bio_caller2 used by the provider %s", pp->name));
632 KASSERT(bp->bio_cflags == bp->_bio_cflags,
633 ("bio_cflags used by the provider %s", pp->name));
634 }
635 #endif
636 KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0"));
637 KASSERT(bp->bio_completed <= bp->bio_length,
638 ("bio_completed can't be greater than bio_length"));
639
640 g_trace(G_T_BIO,
641 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd",
642 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error,
643 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length);
644
645 KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
646 ("Bio already on queue bp=%p", bp));
647
648 /*
649 * XXX: next two doesn't belong here
650 */
651 bp->bio_bcount = bp->bio_length;
652 bp->bio_resid = bp->bio_bcount - bp->bio_completed;
653
654 direct = (pp->flags & G_PF_DIRECT_SEND) &&
655 (cp->flags & G_CF_DIRECT_RECEIVE) &&
656 curthread != g_up_td;
657 if (direct) {
658 /* Block direct execution if less then half of stack left. */
659 size_t st, su;
660 GET_STACK_USAGE(st, su);
661 if (su * 2 > st)
662 direct = 0;
663 }
664
665 /*
666 * The statistics collection is lockless, as such, but we
667 * can not update one instance of the statistics from more
668 * than one thread at a time, so grab the lock first.
669 */
670 if ((g_collectstats & G_STATS_CONSUMERS) != 0 ||
671 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL))
672 binuptime(&now);
673 mtxp = mtx_pool_find(mtxpool_sleep, pp);
674 mtx_lock(mtxp);
675 if (g_collectstats & G_STATS_PROVIDERS)
676 devstat_end_transaction_bio_bt(pp->stat, bp, &now);
677 if (g_collectstats & G_STATS_CONSUMERS)
678 devstat_end_transaction_bio_bt(cp->stat, bp, &now);
679 #ifdef INVARIANTS
680 cp->nend++;
681 #endif
682 mtx_unlock(mtxp);
683
684 if (error != ENOMEM) {
685 bp->bio_error = error;
686 if (direct) {
687 biodone(bp);
688 } else {
689 g_bioq_lock(&g_bio_run_up);
690 first = TAILQ_EMPTY(&g_bio_run_up.bio_queue);
691 TAILQ_INSERT_TAIL(&g_bio_run_up.bio_queue, bp, bio_queue);
692 bp->bio_flags |= BIO_ONQUEUE;
693 g_bio_run_up.bio_queue_length++;
694 g_bioq_unlock(&g_bio_run_up);
695 if (first)
696 wakeup(&g_wait_up);
697 }
698 return;
699 }
700
701 if (bootverbose)
702 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name);
703 bp->bio_children = 0;
704 bp->bio_inbed = 0;
705 bp->bio_driver1 = NULL;
706 bp->bio_driver2 = NULL;
707 bp->bio_pflags = 0;
708 g_io_request(bp, cp);
709 pace = 1;
710 return;
711 }
712
713 SYSCTL_DECL(_kern_geom);
714
715 static long transient_maps;
716 SYSCTL_LONG(_kern_geom, OID_AUTO, transient_maps, CTLFLAG_RD,
717 &transient_maps, 0,
718 "Total count of the transient mapping requests");
719 u_int transient_map_retries = 10;
720 SYSCTL_UINT(_kern_geom, OID_AUTO, transient_map_retries, CTLFLAG_RW,
721 &transient_map_retries, 0,
722 "Max count of retries used before giving up on creating transient map");
723 int transient_map_hard_failures;
724 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_hard_failures, CTLFLAG_RD,
725 &transient_map_hard_failures, 0,
726 "Failures to establish the transient mapping due to retry attempts "
727 "exhausted");
728 int transient_map_soft_failures;
729 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_soft_failures, CTLFLAG_RD,
730 &transient_map_soft_failures, 0,
731 "Count of retried failures to establish the transient mapping");
732 int inflight_transient_maps;
733 SYSCTL_INT(_kern_geom, OID_AUTO, inflight_transient_maps, CTLFLAG_RD,
734 &inflight_transient_maps, 0,
735 "Current count of the active transient maps");
736
737 static int
738 g_io_transient_map_bio(struct bio *bp)
739 {
740 vm_offset_t addr;
741 long size;
742 u_int retried;
743
744 KASSERT(unmapped_buf_allowed, ("unmapped disabled"));
745
746 size = round_page(bp->bio_ma_offset + bp->bio_length);
747 KASSERT(size / PAGE_SIZE == bp->bio_ma_n, ("Bio too short %p", bp));
748 addr = 0;
749 retried = 0;
750 atomic_add_long(&transient_maps, 1);
751 retry:
752 if (vmem_alloc(transient_arena, size, M_BESTFIT | M_NOWAIT, &addr)) {
753 if (transient_map_retries != 0 &&
754 retried >= transient_map_retries) {
755 CTR2(KTR_GEOM, "g_down cannot map bp %p provider %s",
756 bp, bp->bio_to->name);
757 atomic_add_int(&transient_map_hard_failures, 1);
758 return (EDEADLK/* XXXKIB */);
759 } else {
760 /*
761 * Naive attempt to quisce the I/O to get more
762 * in-flight requests completed and defragment
763 * the transient_arena.
764 */
765 CTR3(KTR_GEOM, "g_down retrymap bp %p provider %s r %d",
766 bp, bp->bio_to->name, retried);
767 pause("g_d_tra", hz / 10);
768 retried++;
769 atomic_add_int(&transient_map_soft_failures, 1);
770 goto retry;
771 }
772 }
773 atomic_add_int(&inflight_transient_maps, 1);
774 pmap_qenter((vm_offset_t)addr, bp->bio_ma, OFF_TO_IDX(size));
775 bp->bio_data = (caddr_t)addr + bp->bio_ma_offset;
776 bp->bio_flags |= BIO_TRANSIENT_MAPPING;
777 bp->bio_flags &= ~BIO_UNMAPPED;
778 return (EJUSTRETURN);
779 }
780
781 void
782 g_io_schedule_down(struct thread *tp __unused)
783 {
784 struct bio *bp;
785 int error;
786
787 for(;;) {
788 g_bioq_lock(&g_bio_run_down);
789 bp = g_bioq_first(&g_bio_run_down);
790 if (bp == NULL) {
791 CTR0(KTR_GEOM, "g_down going to sleep");
792 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock,
793 PRIBIO | PDROP, "-", 0);
794 continue;
795 }
796 CTR0(KTR_GEOM, "g_down has work to do");
797 g_bioq_unlock(&g_bio_run_down);
798 biotrack(bp, __func__);
799 if (pace != 0) {
800 /*
801 * There has been at least one memory allocation
802 * failure since the last I/O completed. Pause 1ms to
803 * give the system a chance to free up memory. We only
804 * do this once because a large number of allocations
805 * can fail in the direct dispatch case and there's no
806 * relationship between the number of these failures and
807 * the length of the outage. If there's still an outage,
808 * we'll pause again and again until it's
809 * resolved. Older versions paused longer and once per
810 * allocation failure. This was OK for a single threaded
811 * g_down, but with direct dispatch would lead to max of
812 * 10 IOPs for minutes at a time when transient memory
813 * issues prevented allocation for a batch of requests
814 * from the upper layers.
815 *
816 * XXX This pacing is really lame. It needs to be solved
817 * by other methods. This is OK only because the worst
818 * case scenario is so rare. In the worst case scenario
819 * all memory is tied up waiting for I/O to complete
820 * which can never happen since we can't allocate bios
821 * for that I/O.
822 */
823 CTR0(KTR_GEOM, "g_down pacing self");
824 pause("g_down", min(hz/1000, 1));
825 pace = 0;
826 }
827 CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp,
828 bp->bio_to->name);
829 error = g_io_check(bp);
830 if (error >= 0) {
831 CTR3(KTR_GEOM, "g_down g_io_check on bp %p provider "
832 "%s returned %d", bp, bp->bio_to->name, error);
833 g_io_deliver(bp, error);
834 continue;
835 }
836 THREAD_NO_SLEEPING();
837 CTR4(KTR_GEOM, "g_down starting bp %p provider %s off %ld "
838 "len %ld", bp, bp->bio_to->name, bp->bio_offset,
839 bp->bio_length);
840 bp->bio_to->geom->start(bp);
841 THREAD_SLEEPING_OK();
842 }
843 }
844
845 void
846 g_io_schedule_up(struct thread *tp __unused)
847 {
848 struct bio *bp;
849
850 for(;;) {
851 g_bioq_lock(&g_bio_run_up);
852 bp = g_bioq_first(&g_bio_run_up);
853 if (bp == NULL) {
854 CTR0(KTR_GEOM, "g_up going to sleep");
855 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock,
856 PRIBIO | PDROP, "-", 0);
857 continue;
858 }
859 g_bioq_unlock(&g_bio_run_up);
860 THREAD_NO_SLEEPING();
861 CTR4(KTR_GEOM, "g_up biodone bp %p provider %s off "
862 "%jd len %ld", bp, bp->bio_to->name,
863 bp->bio_offset, bp->bio_length);
864 biodone(bp);
865 THREAD_SLEEPING_OK();
866 }
867 }
868
869 void *
870 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error)
871 {
872 struct bio *bp;
873 void *ptr;
874 int errorc;
875
876 KASSERT(length > 0 && length >= cp->provider->sectorsize &&
877 length <= maxphys, ("g_read_data(): invalid length %jd",
878 (intmax_t)length));
879
880 bp = g_alloc_bio();
881 bp->bio_cmd = BIO_READ;
882 bp->bio_done = NULL;
883 bp->bio_offset = offset;
884 bp->bio_length = length;
885 ptr = g_malloc(length, M_WAITOK);
886 bp->bio_data = ptr;
887 g_io_request(bp, cp);
888 errorc = biowait(bp, "gread");
889 if (errorc == 0 && bp->bio_completed != length)
890 errorc = EIO;
891 if (error != NULL)
892 *error = errorc;
893 g_destroy_bio(bp);
894 if (errorc) {
895 g_free(ptr);
896 ptr = NULL;
897 }
898 return (ptr);
899 }
900
901 /*
902 * A read function for use by ffs_sbget when used by GEOM-layer routines.
903 */
904 int
905 g_use_g_read_data(void *devfd, off_t loc, void **bufp, int size)
906 {
907 struct g_consumer *cp;
908
909 KASSERT(*bufp == NULL,
910 ("g_use_g_read_data: non-NULL *bufp %p\n", *bufp));
911
912 cp = (struct g_consumer *)devfd;
913 /*
914 * Take care not to issue an invalid I/O request. The offset of
915 * the superblock candidate must be multiples of the provider's
916 * sector size, otherwise an FFS can't exist on the provider
917 * anyway.
918 */
919 if (loc % cp->provider->sectorsize != 0)
920 return (ENOENT);
921 *bufp = g_read_data(cp, loc, size, NULL);
922 if (*bufp == NULL)
923 return (ENOENT);
924 return (0);
925 }
926
927 int
928 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length)
929 {
930 struct bio *bp;
931 int error;
932
933 KASSERT(length > 0 && length >= cp->provider->sectorsize &&
934 length <= maxphys, ("g_write_data(): invalid length %jd",
935 (intmax_t)length));
936
937 bp = g_alloc_bio();
938 bp->bio_cmd = BIO_WRITE;
939 bp->bio_done = NULL;
940 bp->bio_offset = offset;
941 bp->bio_length = length;
942 bp->bio_data = ptr;
943 g_io_request(bp, cp);
944 error = biowait(bp, "gwrite");
945 if (error == 0 && bp->bio_completed != length)
946 error = EIO;
947 g_destroy_bio(bp);
948 return (error);
949 }
950
951 /*
952 * A write function for use by ffs_sbput when used by GEOM-layer routines.
953 */
954 int
955 g_use_g_write_data(void *devfd, off_t loc, void *buf, int size)
956 {
957
958 return (g_write_data((struct g_consumer *)devfd, loc, buf, size));
959 }
960
961 int
962 g_delete_data(struct g_consumer *cp, off_t offset, off_t length)
963 {
964 struct bio *bp;
965 int error;
966
967 KASSERT(length > 0 && length >= cp->provider->sectorsize,
968 ("g_delete_data(): invalid length %jd", (intmax_t)length));
969
970 bp = g_alloc_bio();
971 bp->bio_cmd = BIO_DELETE;
972 bp->bio_done = NULL;
973 bp->bio_offset = offset;
974 bp->bio_length = length;
975 bp->bio_data = NULL;
976 g_io_request(bp, cp);
977 error = biowait(bp, "gdelete");
978 if (error == 0 && bp->bio_completed != length)
979 error = EIO;
980 g_destroy_bio(bp);
981 return (error);
982 }
983
984 void
985 g_print_bio(const char *prefix, const struct bio *bp, const char *fmtsuffix,
986 ...)
987 {
988 #ifndef PRINTF_BUFR_SIZE
989 #define PRINTF_BUFR_SIZE 64
990 #endif
991 char bufr[PRINTF_BUFR_SIZE];
992 struct sbuf sb, *sbp __unused;
993 va_list ap;
994
995 sbp = sbuf_new(&sb, bufr, sizeof(bufr), SBUF_FIXEDLEN);
996 KASSERT(sbp != NULL, ("sbuf_new misused?"));
997
998 sbuf_set_drain(&sb, sbuf_printf_drain, NULL);
999
1000 sbuf_cat(&sb, prefix);
1001 g_format_bio(&sb, bp);
1002
1003 va_start(ap, fmtsuffix);
1004 sbuf_vprintf(&sb, fmtsuffix, ap);
1005 va_end(ap);
1006
1007 sbuf_nl_terminate(&sb);
1008
1009 sbuf_finish(&sb);
1010 sbuf_delete(&sb);
1011 }
1012
1013 void
1014 g_format_bio(struct sbuf *sb, const struct bio *bp)
1015 {
1016 const char *pname, *cmd = NULL;
1017
1018 if (bp->bio_to != NULL)
1019 pname = bp->bio_to->name;
1020 else if (bp->bio_parent != NULL && bp->bio_parent->bio_to != NULL)
1021 pname = bp->bio_parent->bio_to->name;
1022 else
1023 pname = "[unknown]";
1024
1025 switch (bp->bio_cmd) {
1026 case BIO_GETATTR:
1027 cmd = "GETATTR";
1028 sbuf_printf(sb, "%s[%s(attr=%s)]", pname, cmd,
1029 bp->bio_attribute);
1030 return;
1031 case BIO_FLUSH:
1032 cmd = "FLUSH";
1033 sbuf_printf(sb, "%s[%s]", pname, cmd);
1034 return;
1035 case BIO_ZONE: {
1036 char *subcmd = NULL;
1037 cmd = "ZONE";
1038 switch (bp->bio_zone.zone_cmd) {
1039 case DISK_ZONE_OPEN:
1040 subcmd = "OPEN";
1041 break;
1042 case DISK_ZONE_CLOSE:
1043 subcmd = "CLOSE";
1044 break;
1045 case DISK_ZONE_FINISH:
1046 subcmd = "FINISH";
1047 break;
1048 case DISK_ZONE_RWP:
1049 subcmd = "RWP";
1050 break;
1051 case DISK_ZONE_REPORT_ZONES:
1052 subcmd = "REPORT ZONES";
1053 break;
1054 case DISK_ZONE_GET_PARAMS:
1055 subcmd = "GET PARAMS";
1056 break;
1057 default:
1058 subcmd = "UNKNOWN";
1059 break;
1060 }
1061 sbuf_printf(sb, "%s[%s,%s]", pname, cmd, subcmd);
1062 return;
1063 }
1064 case BIO_READ:
1065 cmd = "READ";
1066 break;
1067 case BIO_WRITE:
1068 cmd = "WRITE";
1069 break;
1070 case BIO_DELETE:
1071 cmd = "DELETE";
1072 break;
1073 default:
1074 cmd = "UNKNOWN";
1075 sbuf_printf(sb, "%s[%s()]", pname, cmd);
1076 return;
1077 }
1078 sbuf_printf(sb, "%s[%s(offset=%jd, length=%jd)]", pname, cmd,
1079 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length);
1080 }
Cache object: dc2897885f90dfc2ebc033beacae0fa2
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