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 #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/sbuf.h>
51 #include <sys/stack.h>
52 #include <sys/sysctl.h>
53 #include <sys/vmem.h>
54 #include <machine/stack.h>
55 #include <machine/stdarg.h>
56
57 #include <sys/errno.h>
58 #include <geom/geom.h>
59 #include <geom/geom_int.h>
60 #include <sys/devicestat.h>
61
62 #include <vm/uma.h>
63 #include <vm/vm.h>
64 #include <vm/vm_param.h>
65 #include <vm/vm_kern.h>
66 #include <vm/vm_page.h>
67 #include <vm/vm_object.h>
68 #include <vm/vm_extern.h>
69 #include <vm/vm_map.h>
70
71 #define KTR_GEOM_ENABLED \
72 ((KTR_COMPILE & KTR_GEOM) != 0 && (ktr_mask & KTR_GEOM) != 0)
73
74 static int g_io_transient_map_bio(struct bio *bp);
75
76 static struct g_bioq g_bio_run_down;
77 static struct g_bioq g_bio_run_up;
78
79 /*
80 * Pace is a hint that we've had some trouble recently allocating
81 * bios, so we should back off trying to send I/O down the stack
82 * a bit to let the problem resolve. When pacing, we also turn
83 * off direct dispatch to also reduce memory pressure from I/Os
84 * there, at the expxense of some added latency while the memory
85 * pressures exist. See g_io_schedule_down() for more details
86 * and limitations.
87 */
88 static volatile u_int __read_mostly pace;
89
90 static uma_zone_t __read_mostly biozone;
91
92 #include <machine/atomic.h>
93
94 static void
g_bioq_lock(struct g_bioq * bq)95 g_bioq_lock(struct g_bioq *bq)
96 {
97
98 mtx_lock(&bq->bio_queue_lock);
99 }
100
101 static void
g_bioq_unlock(struct g_bioq * bq)102 g_bioq_unlock(struct g_bioq *bq)
103 {
104
105 mtx_unlock(&bq->bio_queue_lock);
106 }
107
108 #if 0
109 static void
110 g_bioq_destroy(struct g_bioq *bq)
111 {
112
113 mtx_destroy(&bq->bio_queue_lock);
114 }
115 #endif
116
117 static void
g_bioq_init(struct g_bioq * bq)118 g_bioq_init(struct g_bioq *bq)
119 {
120
121 TAILQ_INIT(&bq->bio_queue);
122 mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF);
123 }
124
125 static struct bio *
g_bioq_first(struct g_bioq * bq)126 g_bioq_first(struct g_bioq *bq)
127 {
128 struct bio *bp;
129
130 bp = TAILQ_FIRST(&bq->bio_queue);
131 if (bp != NULL) {
132 KASSERT((bp->bio_flags & BIO_ONQUEUE),
133 ("Bio not on queue bp=%p target %p", bp, bq));
134 bp->bio_flags &= ~BIO_ONQUEUE;
135 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue);
136 bq->bio_queue_length--;
137 }
138 return (bp);
139 }
140
141 struct bio *
g_new_bio(void)142 g_new_bio(void)
143 {
144 struct bio *bp;
145
146 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO);
147 #ifdef KTR
148 if (KTR_GEOM_ENABLED) {
149 struct stack st;
150
151 CTR1(KTR_GEOM, "g_new_bio(): %p", bp);
152 stack_save(&st);
153 CTRSTACK(KTR_GEOM, &st, 3);
154 }
155 #endif
156 return (bp);
157 }
158
159 struct bio *
g_alloc_bio(void)160 g_alloc_bio(void)
161 {
162 struct bio *bp;
163
164 bp = uma_zalloc(biozone, M_WAITOK | M_ZERO);
165 #ifdef KTR
166 if (KTR_GEOM_ENABLED) {
167 struct stack st;
168
169 CTR1(KTR_GEOM, "g_alloc_bio(): %p", bp);
170 stack_save(&st);
171 CTRSTACK(KTR_GEOM, &st, 3);
172 }
173 #endif
174 return (bp);
175 }
176
177 void
g_destroy_bio(struct bio * bp)178 g_destroy_bio(struct bio *bp)
179 {
180 #ifdef KTR
181 if (KTR_GEOM_ENABLED) {
182 struct stack st;
183
184 CTR1(KTR_GEOM, "g_destroy_bio(): %p", bp);
185 stack_save(&st);
186 CTRSTACK(KTR_GEOM, &st, 3);
187 }
188 #endif
189 uma_zfree(biozone, bp);
190 }
191
192 struct bio *
g_clone_bio(struct bio * bp)193 g_clone_bio(struct bio *bp)
194 {
195 struct bio *bp2;
196
197 bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO);
198 if (bp2 != NULL) {
199 bp2->bio_parent = bp;
200 bp2->bio_cmd = bp->bio_cmd;
201 /*
202 * BIO_ORDERED flag may be used by disk drivers to enforce
203 * ordering restrictions, so this flag needs to be cloned.
204 * BIO_UNMAPPED, BIO_VLIST, and BIO_SWAP should be inherited,
205 * to properly indicate which way the buffer is passed.
206 * Other bio flags are not suitable for cloning.
207 */
208 bp2->bio_flags = bp->bio_flags &
209 (BIO_ORDERED | BIO_UNMAPPED | BIO_VLIST | BIO_SWAP);
210 bp2->bio_length = bp->bio_length;
211 bp2->bio_offset = bp->bio_offset;
212 bp2->bio_data = bp->bio_data;
213 bp2->bio_ma = bp->bio_ma;
214 bp2->bio_ma_n = bp->bio_ma_n;
215 bp2->bio_ma_offset = bp->bio_ma_offset;
216 bp2->bio_attribute = bp->bio_attribute;
217 if (bp->bio_cmd == BIO_ZONE)
218 bcopy(&bp->bio_zone, &bp2->bio_zone,
219 sizeof(bp->bio_zone));
220 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING)
221 bp2->bio_track_bp = bp->bio_track_bp;
222 #endif
223 bp->bio_children++;
224 }
225 #ifdef KTR
226 if (KTR_GEOM_ENABLED) {
227 struct stack st;
228
229 CTR2(KTR_GEOM, "g_clone_bio(%p): %p", bp, bp2);
230 stack_save(&st);
231 CTRSTACK(KTR_GEOM, &st, 3);
232 }
233 #endif
234 return(bp2);
235 }
236
237 struct bio *
g_duplicate_bio(struct bio * bp)238 g_duplicate_bio(struct bio *bp)
239 {
240 struct bio *bp2;
241
242 bp2 = uma_zalloc(biozone, M_WAITOK | M_ZERO);
243 bp2->bio_flags = bp->bio_flags & (BIO_UNMAPPED | BIO_VLIST | BIO_SWAP);
244 bp2->bio_parent = bp;
245 bp2->bio_cmd = bp->bio_cmd;
246 bp2->bio_length = bp->bio_length;
247 bp2->bio_offset = bp->bio_offset;
248 bp2->bio_data = bp->bio_data;
249 bp2->bio_ma = bp->bio_ma;
250 bp2->bio_ma_n = bp->bio_ma_n;
251 bp2->bio_ma_offset = bp->bio_ma_offset;
252 bp2->bio_attribute = bp->bio_attribute;
253 bp->bio_children++;
254 #ifdef KTR
255 if (KTR_GEOM_ENABLED) {
256 struct stack st;
257
258 CTR2(KTR_GEOM, "g_duplicate_bio(%p): %p", bp, bp2);
259 stack_save(&st);
260 CTRSTACK(KTR_GEOM, &st, 3);
261 }
262 #endif
263 return(bp2);
264 }
265
266 void
g_reset_bio(struct bio * bp)267 g_reset_bio(struct bio *bp)
268 {
269
270 bzero(bp, sizeof(*bp));
271 }
272
273 void
g_io_init(void)274 g_io_init(void)
275 {
276
277 g_bioq_init(&g_bio_run_down);
278 g_bioq_init(&g_bio_run_up);
279 biozone = uma_zcreate("g_bio", sizeof (struct bio),
280 NULL, NULL,
281 NULL, NULL,
282 0, 0);
283 }
284
285 int
g_io_getattr(const char * attr,struct g_consumer * cp,int * len,void * ptr)286 g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr)
287 {
288 struct bio *bp;
289 int error;
290
291 g_trace(G_T_BIO, "bio_getattr(%s)", attr);
292 bp = g_alloc_bio();
293 bp->bio_cmd = BIO_GETATTR;
294 bp->bio_done = NULL;
295 bp->bio_attribute = attr;
296 bp->bio_length = *len;
297 bp->bio_data = ptr;
298 g_io_request(bp, cp);
299 error = biowait(bp, "ggetattr");
300 *len = bp->bio_completed;
301 g_destroy_bio(bp);
302 return (error);
303 }
304
305 int
g_io_zonecmd(struct disk_zone_args * zone_args,struct g_consumer * cp)306 g_io_zonecmd(struct disk_zone_args *zone_args, struct g_consumer *cp)
307 {
308 struct bio *bp;
309 int error;
310
311 g_trace(G_T_BIO, "bio_zone(%d)", zone_args->zone_cmd);
312 bp = g_alloc_bio();
313 bp->bio_cmd = BIO_ZONE;
314 bp->bio_done = NULL;
315 /*
316 * XXX KDM need to handle report zone data.
317 */
318 bcopy(zone_args, &bp->bio_zone, sizeof(*zone_args));
319 if (zone_args->zone_cmd == DISK_ZONE_REPORT_ZONES)
320 bp->bio_length =
321 zone_args->zone_params.report.entries_allocated *
322 sizeof(struct disk_zone_rep_entry);
323 else
324 bp->bio_length = 0;
325
326 g_io_request(bp, cp);
327 error = biowait(bp, "gzone");
328 bcopy(&bp->bio_zone, zone_args, sizeof(*zone_args));
329 g_destroy_bio(bp);
330 return (error);
331 }
332
333 /*
334 * Send a BIO_SPEEDUP down the stack. This is used to tell the lower layers that
335 * the upper layers have detected a resource shortage. The lower layers are
336 * advised to stop delaying I/O that they might be holding for performance
337 * reasons and to schedule it (non-trims) or complete it successfully (trims) as
338 * quickly as it can. bio_length is the amount of the shortage. This call
339 * should be non-blocking. bio_resid is used to communicate back if the lower
340 * layers couldn't find bio_length worth of I/O to schedule or discard. A length
341 * of 0 means to do as much as you can (schedule the h/w queues full, discard
342 * all trims). flags are a hint from the upper layers to the lower layers what
343 * operation should be done.
344 */
345 int
g_io_speedup(off_t shortage,u_int flags,size_t * resid,struct g_consumer * cp)346 g_io_speedup(off_t shortage, u_int flags, size_t *resid, struct g_consumer *cp)
347 {
348 struct bio *bp;
349 int error;
350
351 KASSERT((flags & (BIO_SPEEDUP_TRIM | BIO_SPEEDUP_WRITE)) != 0,
352 ("Invalid flags passed to g_io_speedup: %#x", flags));
353 g_trace(G_T_BIO, "bio_speedup(%s, %jd, %#x)", cp->provider->name,
354 (intmax_t)shortage, flags);
355 bp = g_new_bio();
356 if (bp == NULL)
357 return (ENOMEM);
358 bp->bio_cmd = BIO_SPEEDUP;
359 bp->bio_length = shortage;
360 bp->bio_done = NULL;
361 bp->bio_flags |= flags;
362 g_io_request(bp, cp);
363 error = biowait(bp, "gflush");
364 *resid = bp->bio_resid;
365 g_destroy_bio(bp);
366 return (error);
367 }
368
369 int
g_io_flush(struct g_consumer * cp)370 g_io_flush(struct g_consumer *cp)
371 {
372 struct bio *bp;
373 int error;
374
375 g_trace(G_T_BIO, "bio_flush(%s)", cp->provider->name);
376 bp = g_alloc_bio();
377 bp->bio_cmd = BIO_FLUSH;
378 bp->bio_flags |= BIO_ORDERED;
379 bp->bio_done = NULL;
380 bp->bio_attribute = NULL;
381 bp->bio_offset = cp->provider->mediasize;
382 bp->bio_length = 0;
383 bp->bio_data = NULL;
384 g_io_request(bp, cp);
385 error = biowait(bp, "gflush");
386 g_destroy_bio(bp);
387 return (error);
388 }
389
390 static int
g_io_check(struct bio * bp)391 g_io_check(struct bio *bp)
392 {
393 struct g_consumer *cp;
394 struct g_provider *pp;
395 off_t excess;
396 int error;
397
398 biotrack(bp, __func__);
399
400 cp = bp->bio_from;
401 pp = bp->bio_to;
402
403 /* Fail if access counters dont allow the operation */
404 switch(bp->bio_cmd) {
405 case BIO_READ:
406 case BIO_GETATTR:
407 if (cp->acr == 0)
408 return (EPERM);
409 break;
410 case BIO_WRITE:
411 case BIO_DELETE:
412 case BIO_SPEEDUP:
413 case BIO_FLUSH:
414 if (cp->acw == 0)
415 return (EPERM);
416 break;
417 case BIO_ZONE:
418 if ((bp->bio_zone.zone_cmd == DISK_ZONE_REPORT_ZONES) ||
419 (bp->bio_zone.zone_cmd == DISK_ZONE_GET_PARAMS)) {
420 if (cp->acr == 0)
421 return (EPERM);
422 } else if (cp->acw == 0)
423 return (EPERM);
424 break;
425 default:
426 return (EPERM);
427 }
428 /* if provider is marked for error, don't disturb. */
429 if (pp->error)
430 return (pp->error);
431 if (cp->flags & G_CF_ORPHAN)
432 return (ENXIO);
433
434 switch(bp->bio_cmd) {
435 case BIO_READ:
436 case BIO_WRITE:
437 case BIO_DELETE:
438 /* Zero sectorsize or mediasize is probably a lack of media. */
439 if (pp->sectorsize == 0 || pp->mediasize == 0)
440 return (ENXIO);
441 /* Reject I/O not on sector boundary */
442 if (bp->bio_offset % pp->sectorsize)
443 return (EINVAL);
444 /* Reject I/O not integral sector long */
445 if (bp->bio_length % pp->sectorsize)
446 return (EINVAL);
447 /* Reject requests before or past the end of media. */
448 if (bp->bio_offset < 0)
449 return (EIO);
450 if (bp->bio_offset > pp->mediasize)
451 return (EIO);
452
453 /* Truncate requests to the end of providers media. */
454 excess = bp->bio_offset + bp->bio_length;
455 if (excess > bp->bio_to->mediasize) {
456 KASSERT((bp->bio_flags & BIO_UNMAPPED) == 0 ||
457 round_page(bp->bio_ma_offset +
458 bp->bio_length) / PAGE_SIZE == bp->bio_ma_n,
459 ("excess bio %p too short", bp));
460 excess -= bp->bio_to->mediasize;
461 bp->bio_length -= excess;
462 if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
463 bp->bio_ma_n = round_page(bp->bio_ma_offset +
464 bp->bio_length) / PAGE_SIZE;
465 }
466 if (excess > 0)
467 CTR3(KTR_GEOM, "g_down truncated bio "
468 "%p provider %s by %d", bp,
469 bp->bio_to->name, excess);
470 }
471
472 /* Deliver zero length transfers right here. */
473 if (bp->bio_length == 0) {
474 CTR2(KTR_GEOM, "g_down terminated 0-length "
475 "bp %p provider %s", bp, bp->bio_to->name);
476 return (0);
477 }
478
479 if ((bp->bio_flags & BIO_UNMAPPED) != 0 &&
480 (bp->bio_to->flags & G_PF_ACCEPT_UNMAPPED) == 0 &&
481 (bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE)) {
482 if ((error = g_io_transient_map_bio(bp)) >= 0)
483 return (error);
484 }
485 break;
486 default:
487 break;
488 }
489 return (EJUSTRETURN);
490 }
491
492 void
g_io_request(struct bio * bp,struct g_consumer * cp)493 g_io_request(struct bio *bp, struct g_consumer *cp)
494 {
495 struct g_provider *pp;
496 int direct, error, first;
497 uint8_t cmd;
498
499 biotrack(bp, __func__);
500
501 KASSERT(cp != NULL, ("NULL cp in g_io_request"));
502 KASSERT(bp != NULL, ("NULL bp in g_io_request"));
503 pp = cp->provider;
504 KASSERT(pp != NULL, ("consumer not attached in g_io_request"));
505 #ifdef DIAGNOSTIC
506 KASSERT(bp->bio_driver1 == NULL,
507 ("bio_driver1 used by the consumer (geom %s)", cp->geom->name));
508 KASSERT(bp->bio_driver2 == NULL,
509 ("bio_driver2 used by the consumer (geom %s)", cp->geom->name));
510 KASSERT(bp->bio_pflags == 0,
511 ("bio_pflags used by the consumer (geom %s)", cp->geom->name));
512 /*
513 * Remember consumer's private fields, so we can detect if they were
514 * modified by the provider.
515 */
516 bp->_bio_caller1 = bp->bio_caller1;
517 bp->_bio_caller2 = bp->bio_caller2;
518 bp->_bio_cflags = bp->bio_cflags;
519 #endif
520
521 cmd = bp->bio_cmd;
522 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_GETATTR) {
523 KASSERT(bp->bio_data != NULL,
524 ("NULL bp->data in g_io_request(cmd=%hu)", bp->bio_cmd));
525 }
526 if (cmd == BIO_DELETE || cmd == BIO_FLUSH || cmd == BIO_SPEEDUP) {
527 KASSERT(bp->bio_data == NULL,
528 ("non-NULL bp->data in g_io_request(cmd=%hu)",
529 bp->bio_cmd));
530 }
531 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_DELETE) {
532 KASSERT(bp->bio_offset % cp->provider->sectorsize == 0,
533 ("wrong offset %jd for sectorsize %u",
534 bp->bio_offset, cp->provider->sectorsize));
535 KASSERT(bp->bio_length % cp->provider->sectorsize == 0,
536 ("wrong length %jd for sectorsize %u",
537 bp->bio_length, cp->provider->sectorsize));
538 }
539
540 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d",
541 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd);
542
543 bp->bio_from = cp;
544 bp->bio_to = pp;
545 bp->bio_error = 0;
546 bp->bio_completed = 0;
547
548 KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
549 ("Bio already on queue bp=%p", bp));
550
551 if ((g_collectstats & G_STATS_CONSUMERS) != 0 ||
552 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL))
553 binuptime(&bp->bio_t0);
554 else
555 getbinuptime(&bp->bio_t0);
556 if (g_collectstats & G_STATS_CONSUMERS)
557 devstat_start_transaction_bio_t0(cp->stat, bp);
558 if (g_collectstats & G_STATS_PROVIDERS)
559 devstat_start_transaction_bio_t0(pp->stat, bp);
560 #ifdef INVARIANTS
561 atomic_add_int(&cp->nstart, 1);
562 #endif
563
564 direct = (cp->flags & G_CF_DIRECT_SEND) != 0 &&
565 (pp->flags & G_PF_DIRECT_RECEIVE) != 0 &&
566 curthread != g_down_td &&
567 ((pp->flags & G_PF_ACCEPT_UNMAPPED) != 0 ||
568 (bp->bio_flags & BIO_UNMAPPED) == 0 || THREAD_CAN_SLEEP()) &&
569 pace == 0;
570 if (direct) {
571 /* Block direct execution if less then half of stack left. */
572 size_t st, su;
573 GET_STACK_USAGE(st, su);
574 if (su * 2 > st)
575 direct = 0;
576 }
577
578 if (direct) {
579 error = g_io_check(bp);
580 if (error >= 0) {
581 CTR3(KTR_GEOM, "g_io_request g_io_check on bp %p "
582 "provider %s returned %d", bp, bp->bio_to->name,
583 error);
584 g_io_deliver(bp, error);
585 return;
586 }
587 bp->bio_to->geom->start(bp);
588 } else {
589 g_bioq_lock(&g_bio_run_down);
590 first = TAILQ_EMPTY(&g_bio_run_down.bio_queue);
591 TAILQ_INSERT_TAIL(&g_bio_run_down.bio_queue, bp, bio_queue);
592 bp->bio_flags |= BIO_ONQUEUE;
593 g_bio_run_down.bio_queue_length++;
594 g_bioq_unlock(&g_bio_run_down);
595 /* Pass it on down. */
596 if (first)
597 wakeup(&g_wait_down);
598 }
599 }
600
601 void
g_io_deliver(struct bio * bp,int error)602 g_io_deliver(struct bio *bp, int error)
603 {
604 struct bintime now;
605 struct g_consumer *cp;
606 struct g_provider *pp;
607 struct mtx *mtxp;
608 int direct, first;
609
610 biotrack(bp, __func__);
611
612 KASSERT(bp != NULL, ("NULL bp in g_io_deliver"));
613 pp = bp->bio_to;
614 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver"));
615 cp = bp->bio_from;
616 if (cp == NULL) {
617 bp->bio_error = error;
618 bp->bio_done(bp);
619 return;
620 }
621 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver"));
622 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver"));
623 #ifdef DIAGNOSTIC
624 /*
625 * Some classes - GJournal in particular - can modify bio's
626 * private fields while the bio is in transit; G_GEOM_VOLATILE_BIO
627 * flag means it's an expected behaviour for that particular geom.
628 */
629 if ((cp->geom->flags & G_GEOM_VOLATILE_BIO) == 0) {
630 KASSERT(bp->bio_caller1 == bp->_bio_caller1,
631 ("bio_caller1 used by the provider %s", pp->name));
632 KASSERT(bp->bio_caller2 == bp->_bio_caller2,
633 ("bio_caller2 used by the provider %s", pp->name));
634 KASSERT(bp->bio_cflags == bp->_bio_cflags,
635 ("bio_cflags used by the provider %s", pp->name));
636 }
637 #endif
638 KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0"));
639 KASSERT(bp->bio_completed <= bp->bio_length,
640 ("bio_completed can't be greater than bio_length"));
641
642 g_trace(G_T_BIO,
643 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd",
644 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error,
645 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length);
646
647 KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
648 ("Bio already on queue bp=%p", bp));
649
650 /*
651 * XXX: next two doesn't belong here
652 */
653 bp->bio_bcount = bp->bio_length;
654 bp->bio_resid = bp->bio_bcount - bp->bio_completed;
655
656 direct = (pp->flags & G_PF_DIRECT_SEND) &&
657 (cp->flags & G_CF_DIRECT_RECEIVE) &&
658 curthread != g_up_td;
659 if (direct) {
660 /* Block direct execution if less then half of stack left. */
661 size_t st, su;
662 GET_STACK_USAGE(st, su);
663 if (su * 2 > st)
664 direct = 0;
665 }
666
667 /*
668 * The statistics collection is lockless, as such, but we
669 * can not update one instance of the statistics from more
670 * than one thread at a time, so grab the lock first.
671 */
672 if ((g_collectstats & G_STATS_CONSUMERS) != 0 ||
673 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL))
674 binuptime(&now);
675 mtxp = mtx_pool_find(mtxpool_sleep, pp);
676 mtx_lock(mtxp);
677 if (g_collectstats & G_STATS_PROVIDERS)
678 devstat_end_transaction_bio_bt(pp->stat, bp, &now);
679 if (g_collectstats & G_STATS_CONSUMERS)
680 devstat_end_transaction_bio_bt(cp->stat, bp, &now);
681 #ifdef INVARIANTS
682 cp->nend++;
683 #endif
684 mtx_unlock(mtxp);
685
686 if (error != ENOMEM) {
687 bp->bio_error = error;
688 if (direct) {
689 biodone(bp);
690 } else {
691 g_bioq_lock(&g_bio_run_up);
692 first = TAILQ_EMPTY(&g_bio_run_up.bio_queue);
693 TAILQ_INSERT_TAIL(&g_bio_run_up.bio_queue, bp, bio_queue);
694 bp->bio_flags |= BIO_ONQUEUE;
695 g_bio_run_up.bio_queue_length++;
696 g_bioq_unlock(&g_bio_run_up);
697 if (first)
698 wakeup(&g_wait_up);
699 }
700 return;
701 }
702
703 if (bootverbose)
704 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name);
705 bp->bio_children = 0;
706 bp->bio_inbed = 0;
707 bp->bio_driver1 = NULL;
708 bp->bio_driver2 = NULL;
709 bp->bio_pflags = 0;
710 g_io_request(bp, cp);
711 pace = 1;
712 return;
713 }
714
715 SYSCTL_DECL(_kern_geom);
716
717 static long transient_maps;
718 SYSCTL_LONG(_kern_geom, OID_AUTO, transient_maps, CTLFLAG_RD,
719 &transient_maps, 0,
720 "Total count of the transient mapping requests");
721 u_int transient_map_retries = 10;
722 SYSCTL_UINT(_kern_geom, OID_AUTO, transient_map_retries, CTLFLAG_RW,
723 &transient_map_retries, 0,
724 "Max count of retries used before giving up on creating transient map");
725 int transient_map_hard_failures;
726 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_hard_failures, CTLFLAG_RD,
727 &transient_map_hard_failures, 0,
728 "Failures to establish the transient mapping due to retry attempts "
729 "exhausted");
730 int transient_map_soft_failures;
731 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_soft_failures, CTLFLAG_RD,
732 &transient_map_soft_failures, 0,
733 "Count of retried failures to establish the transient mapping");
734 int inflight_transient_maps;
735 SYSCTL_INT(_kern_geom, OID_AUTO, inflight_transient_maps, CTLFLAG_RD,
736 &inflight_transient_maps, 0,
737 "Current count of the active transient maps");
738
739 static int
g_io_transient_map_bio(struct bio * bp)740 g_io_transient_map_bio(struct bio *bp)
741 {
742 vm_offset_t addr;
743 long size;
744 u_int retried;
745
746 KASSERT(unmapped_buf_allowed, ("unmapped disabled"));
747
748 size = round_page(bp->bio_ma_offset + bp->bio_length);
749 KASSERT(size / PAGE_SIZE == bp->bio_ma_n, ("Bio too short %p", bp));
750 addr = 0;
751 retried = 0;
752 atomic_add_long(&transient_maps, 1);
753 retry:
754 if (vmem_alloc(transient_arena, size, M_BESTFIT | M_NOWAIT, &addr)) {
755 if (transient_map_retries != 0 &&
756 retried >= transient_map_retries) {
757 CTR2(KTR_GEOM, "g_down cannot map bp %p provider %s",
758 bp, bp->bio_to->name);
759 atomic_add_int(&transient_map_hard_failures, 1);
760 return (EDEADLK/* XXXKIB */);
761 } else {
762 /*
763 * Naive attempt to quisce the I/O to get more
764 * in-flight requests completed and defragment
765 * the transient_arena.
766 */
767 CTR3(KTR_GEOM, "g_down retrymap bp %p provider %s r %d",
768 bp, bp->bio_to->name, retried);
769 pause("g_d_tra", hz / 10);
770 retried++;
771 atomic_add_int(&transient_map_soft_failures, 1);
772 goto retry;
773 }
774 }
775 atomic_add_int(&inflight_transient_maps, 1);
776 pmap_qenter((vm_offset_t)addr, bp->bio_ma, OFF_TO_IDX(size));
777 bp->bio_data = (caddr_t)addr + bp->bio_ma_offset;
778 bp->bio_flags |= BIO_TRANSIENT_MAPPING;
779 bp->bio_flags &= ~BIO_UNMAPPED;
780 return (EJUSTRETURN);
781 }
782
783 void
g_io_schedule_down(struct thread * tp __unused)784 g_io_schedule_down(struct thread *tp __unused)
785 {
786 struct bio *bp;
787 int error;
788
789 for(;;) {
790 g_bioq_lock(&g_bio_run_down);
791 bp = g_bioq_first(&g_bio_run_down);
792 if (bp == NULL) {
793 CTR0(KTR_GEOM, "g_down going to sleep");
794 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock,
795 PRIBIO | PDROP, "-", 0);
796 continue;
797 }
798 CTR0(KTR_GEOM, "g_down has work to do");
799 g_bioq_unlock(&g_bio_run_down);
800 biotrack(bp, __func__);
801 if (pace != 0) {
802 /*
803 * There has been at least one memory allocation
804 * failure since the last I/O completed. Pause 1ms to
805 * give the system a chance to free up memory. We only
806 * do this once because a large number of allocations
807 * can fail in the direct dispatch case and there's no
808 * relationship between the number of these failures and
809 * the length of the outage. If there's still an outage,
810 * we'll pause again and again until it's
811 * resolved. Older versions paused longer and once per
812 * allocation failure. This was OK for a single threaded
813 * g_down, but with direct dispatch would lead to max of
814 * 10 IOPs for minutes at a time when transient memory
815 * issues prevented allocation for a batch of requests
816 * from the upper layers.
817 *
818 * XXX This pacing is really lame. It needs to be solved
819 * by other methods. This is OK only because the worst
820 * case scenario is so rare. In the worst case scenario
821 * all memory is tied up waiting for I/O to complete
822 * which can never happen since we can't allocate bios
823 * for that I/O.
824 */
825 CTR0(KTR_GEOM, "g_down pacing self");
826 pause("g_down", min(hz/1000, 1));
827 pace = 0;
828 }
829 CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp,
830 bp->bio_to->name);
831 error = g_io_check(bp);
832 if (error >= 0) {
833 CTR3(KTR_GEOM, "g_down g_io_check on bp %p provider "
834 "%s returned %d", bp, bp->bio_to->name, error);
835 g_io_deliver(bp, error);
836 continue;
837 }
838 THREAD_NO_SLEEPING();
839 CTR4(KTR_GEOM, "g_down starting bp %p provider %s off %ld "
840 "len %ld", bp, bp->bio_to->name, bp->bio_offset,
841 bp->bio_length);
842 bp->bio_to->geom->start(bp);
843 THREAD_SLEEPING_OK();
844 }
845 }
846
847 void
g_io_schedule_up(struct thread * tp __unused)848 g_io_schedule_up(struct thread *tp __unused)
849 {
850 struct bio *bp;
851
852 for(;;) {
853 g_bioq_lock(&g_bio_run_up);
854 bp = g_bioq_first(&g_bio_run_up);
855 if (bp == NULL) {
856 CTR0(KTR_GEOM, "g_up going to sleep");
857 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock,
858 PRIBIO | PDROP, "-", 0);
859 continue;
860 }
861 g_bioq_unlock(&g_bio_run_up);
862 THREAD_NO_SLEEPING();
863 CTR4(KTR_GEOM, "g_up biodone bp %p provider %s off "
864 "%jd len %ld", bp, bp->bio_to->name,
865 bp->bio_offset, bp->bio_length);
866 biodone(bp);
867 THREAD_SLEEPING_OK();
868 }
869 }
870
871 void *
g_read_data(struct g_consumer * cp,off_t offset,off_t length,int * error)872 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error)
873 {
874 struct bio *bp;
875 void *ptr;
876 int errorc;
877
878 KASSERT(length > 0 && length >= cp->provider->sectorsize &&
879 length <= maxphys, ("g_read_data(): invalid length %jd",
880 (intmax_t)length));
881
882 bp = g_alloc_bio();
883 bp->bio_cmd = BIO_READ;
884 bp->bio_done = NULL;
885 bp->bio_offset = offset;
886 bp->bio_length = length;
887 ptr = g_malloc(length, M_WAITOK);
888 bp->bio_data = ptr;
889 g_io_request(bp, cp);
890 errorc = biowait(bp, "gread");
891 if (errorc == 0 && bp->bio_completed != length)
892 errorc = EIO;
893 if (error != NULL)
894 *error = errorc;
895 g_destroy_bio(bp);
896 if (errorc) {
897 g_free(ptr);
898 ptr = NULL;
899 }
900 return (ptr);
901 }
902
903 /*
904 * A read function for use by ffs_sbget when used by GEOM-layer routines.
905 */
906 int
g_use_g_read_data(void * devfd,off_t loc,void ** bufp,int size)907 g_use_g_read_data(void *devfd, off_t loc, void **bufp, int size)
908 {
909 struct g_consumer *cp;
910
911 KASSERT(*bufp == NULL,
912 ("g_use_g_read_data: non-NULL *bufp %p\n", *bufp));
913
914 cp = (struct g_consumer *)devfd;
915 /*
916 * Take care not to issue an invalid I/O request. The offset of
917 * the superblock candidate must be multiples of the provider's
918 * sector size, otherwise an FFS can't exist on the provider
919 * anyway.
920 */
921 if (loc % cp->provider->sectorsize != 0)
922 return (ENOENT);
923 *bufp = g_read_data(cp, loc, size, NULL);
924 if (*bufp == NULL)
925 return (ENOENT);
926 return (0);
927 }
928
929 int
g_write_data(struct g_consumer * cp,off_t offset,void * ptr,off_t length)930 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length)
931 {
932 struct bio *bp;
933 int error;
934
935 KASSERT(length > 0 && length >= cp->provider->sectorsize &&
936 length <= maxphys, ("g_write_data(): invalid length %jd",
937 (intmax_t)length));
938
939 bp = g_alloc_bio();
940 bp->bio_cmd = BIO_WRITE;
941 bp->bio_done = NULL;
942 bp->bio_offset = offset;
943 bp->bio_length = length;
944 bp->bio_data = ptr;
945 g_io_request(bp, cp);
946 error = biowait(bp, "gwrite");
947 if (error == 0 && bp->bio_completed != length)
948 error = EIO;
949 g_destroy_bio(bp);
950 return (error);
951 }
952
953 /*
954 * A write function for use by ffs_sbput when used by GEOM-layer routines.
955 */
956 int
g_use_g_write_data(void * devfd,off_t loc,void * buf,int size)957 g_use_g_write_data(void *devfd, off_t loc, void *buf, int size)
958 {
959
960 return (g_write_data((struct g_consumer *)devfd, loc, buf, size));
961 }
962
963 int
g_delete_data(struct g_consumer * cp,off_t offset,off_t length)964 g_delete_data(struct g_consumer *cp, off_t offset, off_t length)
965 {
966 struct bio *bp;
967 int error;
968
969 KASSERT(length > 0 && length >= cp->provider->sectorsize,
970 ("g_delete_data(): invalid length %jd", (intmax_t)length));
971
972 bp = g_alloc_bio();
973 bp->bio_cmd = BIO_DELETE;
974 bp->bio_done = NULL;
975 bp->bio_offset = offset;
976 bp->bio_length = length;
977 bp->bio_data = NULL;
978 g_io_request(bp, cp);
979 error = biowait(bp, "gdelete");
980 if (error == 0 && bp->bio_completed != length)
981 error = EIO;
982 g_destroy_bio(bp);
983 return (error);
984 }
985
986 void
g_print_bio(const char * prefix,const struct bio * bp,const char * fmtsuffix,...)987 g_print_bio(const char *prefix, const struct bio *bp, const char *fmtsuffix,
988 ...)
989 {
990 #ifndef PRINTF_BUFR_SIZE
991 #define PRINTF_BUFR_SIZE 64
992 #endif
993 char bufr[PRINTF_BUFR_SIZE];
994 struct sbuf sb, *sbp __unused;
995 va_list ap;
996
997 sbp = sbuf_new(&sb, bufr, sizeof(bufr), SBUF_FIXEDLEN);
998 KASSERT(sbp != NULL, ("sbuf_new misused?"));
999
1000 sbuf_set_drain(&sb, sbuf_printf_drain, NULL);
1001
1002 sbuf_cat(&sb, prefix);
1003 g_format_bio(&sb, bp);
1004
1005 va_start(ap, fmtsuffix);
1006 sbuf_vprintf(&sb, fmtsuffix, ap);
1007 va_end(ap);
1008
1009 sbuf_nl_terminate(&sb);
1010
1011 sbuf_finish(&sb);
1012 sbuf_delete(&sb);
1013 }
1014
1015 void
g_format_bio(struct sbuf * sb,const struct bio * bp)1016 g_format_bio(struct sbuf *sb, const struct bio *bp)
1017 {
1018 const char *pname, *cmd = NULL;
1019
1020 if (bp->bio_to != NULL)
1021 pname = bp->bio_to->name;
1022 else if (bp->bio_parent != NULL && bp->bio_parent->bio_to != NULL)
1023 pname = bp->bio_parent->bio_to->name;
1024 else
1025 pname = "[unknown]";
1026
1027 switch (bp->bio_cmd) {
1028 case BIO_GETATTR:
1029 cmd = "GETATTR";
1030 sbuf_printf(sb, "%s[%s(attr=%s)]", pname, cmd,
1031 bp->bio_attribute);
1032 return;
1033 case BIO_FLUSH:
1034 cmd = "FLUSH";
1035 sbuf_printf(sb, "%s[%s]", pname, cmd);
1036 return;
1037 case BIO_ZONE: {
1038 char *subcmd = NULL;
1039 cmd = "ZONE";
1040 switch (bp->bio_zone.zone_cmd) {
1041 case DISK_ZONE_OPEN:
1042 subcmd = "OPEN";
1043 break;
1044 case DISK_ZONE_CLOSE:
1045 subcmd = "CLOSE";
1046 break;
1047 case DISK_ZONE_FINISH:
1048 subcmd = "FINISH";
1049 break;
1050 case DISK_ZONE_RWP:
1051 subcmd = "RWP";
1052 break;
1053 case DISK_ZONE_REPORT_ZONES:
1054 subcmd = "REPORT ZONES";
1055 break;
1056 case DISK_ZONE_GET_PARAMS:
1057 subcmd = "GET PARAMS";
1058 break;
1059 default:
1060 subcmd = "UNKNOWN";
1061 break;
1062 }
1063 sbuf_printf(sb, "%s[%s,%s]", pname, cmd, subcmd);
1064 return;
1065 }
1066 case BIO_READ:
1067 cmd = "READ";
1068 break;
1069 case BIO_WRITE:
1070 cmd = "WRITE";
1071 break;
1072 case BIO_DELETE:
1073 cmd = "DELETE";
1074 break;
1075 default:
1076 cmd = "UNKNOWN";
1077 sbuf_printf(sb, "%s[%s()]", pname, cmd);
1078 return;
1079 }
1080 sbuf_printf(sb, "%s[%s(offset=%jd, length=%jd)]", pname, cmd,
1081 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length);
1082 }
1083