1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2003 Sistina Software (UK) Limited.
4 * Copyright (C) 2004, 2010-2011 Red Hat, Inc. All rights reserved.
5 *
6 * This file is released under the GPL.
7 */
8
9 #include <linux/device-mapper.h>
10
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/blkdev.h>
14 #include <linux/bio.h>
15 #include <linux/slab.h>
16
17 #define DM_MSG_PREFIX "flakey"
18
19 #define PROBABILITY_BASE 1000000000
20
21 #define all_corrupt_bio_flags_match(bio, fc) \
22 (((bio)->bi_opf & (fc)->corrupt_bio_flags) == (fc)->corrupt_bio_flags)
23
24 /*
25 * Flakey: Used for testing only, simulates intermittent,
26 * catastrophic device failure.
27 */
28 struct flakey_c {
29 struct dm_dev *dev;
30 unsigned long start_time;
31 sector_t start;
32 unsigned int up_interval;
33 unsigned int down_interval;
34 unsigned long flags;
35 unsigned int corrupt_bio_byte;
36 unsigned int corrupt_bio_rw;
37 unsigned int corrupt_bio_value;
38 blk_opf_t corrupt_bio_flags;
39 unsigned int random_read_corrupt;
40 unsigned int random_write_corrupt;
41 };
42
43 enum feature_flag_bits {
44 ERROR_READS,
45 DROP_WRITES,
46 ERROR_WRITES
47 };
48
49 struct per_bio_data {
50 bool bio_can_corrupt;
51 struct bvec_iter saved_iter;
52 };
53
parse_features(struct dm_arg_set * as,struct flakey_c * fc,struct dm_target * ti)54 static int parse_features(struct dm_arg_set *as, struct flakey_c *fc,
55 struct dm_target *ti)
56 {
57 int r = 0;
58 unsigned int argc = 0;
59 const char *arg_name;
60
61 static const struct dm_arg _args[] = {
62 {0, 11, "Invalid number of feature args"},
63 {1, UINT_MAX, "Invalid corrupt bio byte"},
64 {0, 255, "Invalid corrupt value to write into bio byte (0-255)"},
65 {0, UINT_MAX, "Invalid corrupt bio flags mask"},
66 {0, PROBABILITY_BASE, "Invalid random corrupt argument"},
67 };
68
69 if (as->argc && (r = dm_read_arg_group(_args, as, &argc, &ti->error)))
70 return r;
71
72 /* No feature arguments supplied. */
73 if (!argc)
74 goto error_all_io;
75
76 while (argc) {
77 arg_name = dm_shift_arg(as);
78 argc--;
79
80 if (!arg_name) {
81 ti->error = "Insufficient feature arguments";
82 return -EINVAL;
83 }
84
85 /*
86 * error_reads
87 */
88 if (!strcasecmp(arg_name, "error_reads")) {
89 if (test_and_set_bit(ERROR_READS, &fc->flags)) {
90 ti->error = "Feature error_reads duplicated";
91 return -EINVAL;
92 }
93 continue;
94 }
95
96 /*
97 * drop_writes
98 */
99 if (!strcasecmp(arg_name, "drop_writes")) {
100 if (test_and_set_bit(DROP_WRITES, &fc->flags)) {
101 ti->error = "Feature drop_writes duplicated";
102 return -EINVAL;
103 } else if (test_bit(ERROR_WRITES, &fc->flags)) {
104 ti->error = "Feature drop_writes conflicts with feature error_writes";
105 return -EINVAL;
106 }
107
108 continue;
109 }
110
111 /*
112 * error_writes
113 */
114 if (!strcasecmp(arg_name, "error_writes")) {
115 if (test_and_set_bit(ERROR_WRITES, &fc->flags)) {
116 ti->error = "Feature error_writes duplicated";
117 return -EINVAL;
118
119 } else if (test_bit(DROP_WRITES, &fc->flags)) {
120 ti->error = "Feature error_writes conflicts with feature drop_writes";
121 return -EINVAL;
122 }
123
124 continue;
125 }
126
127 /*
128 * corrupt_bio_byte <Nth_byte> <direction> <value> <bio_flags>
129 */
130 if (!strcasecmp(arg_name, "corrupt_bio_byte")) {
131 if (fc->corrupt_bio_byte) {
132 ti->error = "Feature corrupt_bio_byte duplicated";
133 return -EINVAL;
134 } else if (argc < 4) {
135 ti->error = "Feature corrupt_bio_byte requires 4 parameters";
136 return -EINVAL;
137 }
138
139 r = dm_read_arg(_args + 1, as, &fc->corrupt_bio_byte, &ti->error);
140 if (r)
141 return r;
142 argc--;
143
144 /*
145 * Direction r or w?
146 */
147 arg_name = dm_shift_arg(as);
148 if (arg_name && !strcasecmp(arg_name, "w"))
149 fc->corrupt_bio_rw = WRITE;
150 else if (arg_name && !strcasecmp(arg_name, "r"))
151 fc->corrupt_bio_rw = READ;
152 else {
153 ti->error = "Invalid corrupt bio direction (r or w)";
154 return -EINVAL;
155 }
156 argc--;
157
158 /*
159 * Value of byte (0-255) to write in place of correct one.
160 */
161 r = dm_read_arg(_args + 2, as, &fc->corrupt_bio_value, &ti->error);
162 if (r)
163 return r;
164 argc--;
165
166 /*
167 * Only corrupt bios with these flags set.
168 */
169 BUILD_BUG_ON(sizeof(fc->corrupt_bio_flags) !=
170 sizeof(unsigned int));
171 r = dm_read_arg(_args + 3, as,
172 (__force unsigned int *)&fc->corrupt_bio_flags,
173 &ti->error);
174 if (r)
175 return r;
176 argc--;
177
178 continue;
179 }
180
181 if (!strcasecmp(arg_name, "random_read_corrupt")) {
182 if (fc->random_read_corrupt) {
183 ti->error = "Feature random_read_corrupt duplicated";
184 return -EINVAL;
185 } else if (!argc) {
186 ti->error = "Feature random_read_corrupt requires a parameter";
187 return -EINVAL;
188 }
189 r = dm_read_arg(_args + 4, as, &fc->random_read_corrupt, &ti->error);
190 if (r)
191 return r;
192 argc--;
193
194 continue;
195 }
196
197 if (!strcasecmp(arg_name, "random_write_corrupt")) {
198 if (fc->random_write_corrupt) {
199 ti->error = "Feature random_write_corrupt duplicated";
200 return -EINVAL;
201 } else if (!argc) {
202 ti->error = "Feature random_write_corrupt requires a parameter";
203 return -EINVAL;
204 }
205 r = dm_read_arg(_args + 4, as, &fc->random_write_corrupt, &ti->error);
206 if (r)
207 return r;
208 argc--;
209
210 continue;
211 }
212
213 ti->error = "Unrecognised flakey feature requested";
214 return -EINVAL;
215 }
216
217 if (test_bit(DROP_WRITES, &fc->flags) &&
218 (fc->corrupt_bio_rw == WRITE || fc->random_write_corrupt)) {
219 ti->error = "drop_writes is incompatible with random_write_corrupt or corrupt_bio_byte with the WRITE flag set";
220 return -EINVAL;
221
222 } else if (test_bit(ERROR_WRITES, &fc->flags) &&
223 (fc->corrupt_bio_rw == WRITE || fc->random_write_corrupt)) {
224 ti->error = "error_writes is incompatible with random_write_corrupt or corrupt_bio_byte with the WRITE flag set";
225 return -EINVAL;
226 } else if (test_bit(ERROR_READS, &fc->flags) &&
227 (fc->corrupt_bio_rw == READ || fc->random_read_corrupt)) {
228 ti->error = "error_reads is incompatible with random_read_corrupt or corrupt_bio_byte with the READ flag set";
229 return -EINVAL;
230 }
231
232 if (!fc->corrupt_bio_byte && !test_bit(ERROR_READS, &fc->flags) &&
233 !test_bit(DROP_WRITES, &fc->flags) && !test_bit(ERROR_WRITES, &fc->flags) &&
234 !fc->random_read_corrupt && !fc->random_write_corrupt) {
235 error_all_io:
236 set_bit(ERROR_WRITES, &fc->flags);
237 set_bit(ERROR_READS, &fc->flags);
238 }
239
240 return 0;
241 }
242
243 /*
244 * Construct a flakey mapping:
245 * <dev_path> <offset> <up interval> <down interval> [<#feature args> [<arg>]*]
246 *
247 * Feature args:
248 * [drop_writes]
249 * [corrupt_bio_byte <Nth_byte> <direction> <value> <bio_flags>]
250 *
251 * Nth_byte starts from 1 for the first byte.
252 * Direction is r for READ or w for WRITE.
253 * bio_flags is ignored if 0.
254 */
flakey_ctr(struct dm_target * ti,unsigned int argc,char ** argv)255 static int flakey_ctr(struct dm_target *ti, unsigned int argc, char **argv)
256 {
257 static const struct dm_arg _args[] = {
258 {0, UINT_MAX, "Invalid up interval"},
259 {0, UINT_MAX, "Invalid down interval"},
260 };
261
262 int r;
263 struct flakey_c *fc;
264 unsigned long long tmpll;
265 struct dm_arg_set as;
266 const char *devname;
267 char dummy;
268
269 as.argc = argc;
270 as.argv = argv;
271
272 if (argc < 4) {
273 ti->error = "Invalid argument count";
274 return -EINVAL;
275 }
276
277 fc = kzalloc(sizeof(*fc), GFP_KERNEL);
278 if (!fc) {
279 ti->error = "Cannot allocate context";
280 return -ENOMEM;
281 }
282 fc->start_time = jiffies;
283
284 devname = dm_shift_arg(&as);
285
286 r = -EINVAL;
287 if (sscanf(dm_shift_arg(&as), "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) {
288 ti->error = "Invalid device sector";
289 goto bad;
290 }
291 fc->start = tmpll;
292
293 r = dm_read_arg(_args, &as, &fc->up_interval, &ti->error);
294 if (r)
295 goto bad;
296
297 r = dm_read_arg(_args + 1, &as, &fc->down_interval, &ti->error);
298 if (r)
299 goto bad;
300
301 if (!(fc->up_interval + fc->down_interval)) {
302 ti->error = "Total (up + down) interval is zero";
303 r = -EINVAL;
304 goto bad;
305 }
306
307 if (fc->up_interval + fc->down_interval < fc->up_interval) {
308 ti->error = "Interval overflow";
309 r = -EINVAL;
310 goto bad;
311 }
312
313 r = parse_features(&as, fc, ti);
314 if (r)
315 goto bad;
316
317 r = dm_get_device(ti, devname, dm_table_get_mode(ti->table), &fc->dev);
318 if (r) {
319 ti->error = "Device lookup failed";
320 goto bad;
321 }
322
323 ti->num_flush_bios = 1;
324 ti->num_discard_bios = 1;
325 ti->per_io_data_size = sizeof(struct per_bio_data);
326 ti->private = fc;
327 return 0;
328
329 bad:
330 kfree(fc);
331 return r;
332 }
333
flakey_dtr(struct dm_target * ti)334 static void flakey_dtr(struct dm_target *ti)
335 {
336 struct flakey_c *fc = ti->private;
337
338 dm_put_device(ti, fc->dev);
339 kfree(fc);
340 }
341
flakey_map_sector(struct dm_target * ti,sector_t bi_sector)342 static sector_t flakey_map_sector(struct dm_target *ti, sector_t bi_sector)
343 {
344 struct flakey_c *fc = ti->private;
345
346 return fc->start + dm_target_offset(ti, bi_sector);
347 }
348
flakey_map_bio(struct dm_target * ti,struct bio * bio)349 static void flakey_map_bio(struct dm_target *ti, struct bio *bio)
350 {
351 struct flakey_c *fc = ti->private;
352
353 bio_set_dev(bio, fc->dev->bdev);
354 bio->bi_iter.bi_sector = flakey_map_sector(ti, bio->bi_iter.bi_sector);
355 }
356
corrupt_bio_common(struct bio * bio,unsigned int corrupt_bio_byte,unsigned char corrupt_bio_value,struct bvec_iter start)357 static void corrupt_bio_common(struct bio *bio, unsigned int corrupt_bio_byte,
358 unsigned char corrupt_bio_value,
359 struct bvec_iter start)
360 {
361 struct bvec_iter iter;
362 struct bio_vec bvec;
363
364 /*
365 * Overwrite the Nth byte of the bio's data, on whichever page
366 * it falls.
367 */
368 __bio_for_each_segment(bvec, bio, iter, start) {
369 if (bio_iter_len(bio, iter) > corrupt_bio_byte) {
370 unsigned char *segment = bvec_kmap_local(&bvec);
371 segment[corrupt_bio_byte] = corrupt_bio_value;
372 kunmap_local(segment);
373 DMDEBUG("Corrupting data bio=%p by writing %u to byte %u "
374 "(rw=%c bi_opf=%u bi_sector=%llu size=%u)\n",
375 bio, corrupt_bio_value, corrupt_bio_byte,
376 (bio_data_dir(bio) == WRITE) ? 'w' : 'r', bio->bi_opf,
377 (unsigned long long)start.bi_sector,
378 start.bi_size);
379 break;
380 }
381 corrupt_bio_byte -= bio_iter_len(bio, iter);
382 }
383 }
384
corrupt_bio_data(struct bio * bio,struct flakey_c * fc,struct bvec_iter start)385 static void corrupt_bio_data(struct bio *bio, struct flakey_c *fc,
386 struct bvec_iter start)
387 {
388 unsigned int corrupt_bio_byte = fc->corrupt_bio_byte - 1;
389
390 corrupt_bio_common(bio, corrupt_bio_byte, fc->corrupt_bio_value, start);
391 }
392
corrupt_bio_random(struct bio * bio,struct bvec_iter start)393 static void corrupt_bio_random(struct bio *bio, struct bvec_iter start)
394 {
395 unsigned int corrupt_byte;
396 unsigned char corrupt_value;
397
398 corrupt_byte = get_random_u32() % start.bi_size;
399 corrupt_value = get_random_u8();
400
401 corrupt_bio_common(bio, corrupt_byte, corrupt_value, start);
402 }
403
clone_free(struct bio * clone)404 static void clone_free(struct bio *clone)
405 {
406 struct folio_iter fi;
407
408 if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */
409 bio_for_each_folio_all(fi, clone)
410 folio_put(fi.folio);
411 }
412
413 bio_uninit(clone);
414 kfree(clone);
415 }
416
clone_endio(struct bio * clone)417 static void clone_endio(struct bio *clone)
418 {
419 struct bio *bio = clone->bi_private;
420 bio->bi_status = clone->bi_status;
421 clone_free(clone);
422 bio_endio(bio);
423 }
424
clone_bio(struct dm_target * ti,struct flakey_c * fc,struct bio * bio)425 static struct bio *clone_bio(struct dm_target *ti, struct flakey_c *fc, struct bio *bio)
426 {
427 struct bio *clone;
428 unsigned size, remaining_size, nr_iovecs, order;
429 struct bvec_iter iter = bio->bi_iter;
430
431 if (unlikely(bio->bi_iter.bi_size > UIO_MAXIOV << PAGE_SHIFT))
432 dm_accept_partial_bio(bio, UIO_MAXIOV << PAGE_SHIFT >> SECTOR_SHIFT);
433
434 size = bio->bi_iter.bi_size;
435 nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
436
437 clone = bio_kmalloc(nr_iovecs, GFP_NOIO | __GFP_NORETRY | __GFP_NOWARN);
438 if (!clone)
439 return NULL;
440
441 bio_init(clone, fc->dev->bdev, clone->bi_inline_vecs, nr_iovecs, bio->bi_opf);
442
443 clone->bi_iter.bi_sector = flakey_map_sector(ti, bio->bi_iter.bi_sector);
444 clone->bi_private = bio;
445 clone->bi_end_io = clone_endio;
446
447 remaining_size = size;
448
449 order = MAX_PAGE_ORDER;
450 while (remaining_size) {
451 struct page *pages;
452 unsigned size_to_add, to_copy;
453 unsigned char *virt;
454 unsigned remaining_order = __fls((remaining_size + PAGE_SIZE - 1) >> PAGE_SHIFT);
455 order = min(order, remaining_order);
456
457 retry_alloc_pages:
458 pages = alloc_pages(GFP_NOIO | __GFP_NORETRY | __GFP_NOWARN | __GFP_COMP, order);
459 if (unlikely(!pages)) {
460 if (order) {
461 order--;
462 goto retry_alloc_pages;
463 }
464 clone_free(clone);
465 return NULL;
466 }
467 size_to_add = min((unsigned)PAGE_SIZE << order, remaining_size);
468
469 virt = page_to_virt(pages);
470 to_copy = size_to_add;
471 do {
472 struct bio_vec bvec = bvec_iter_bvec(bio->bi_io_vec, iter);
473 unsigned this_step = min(bvec.bv_len, to_copy);
474 void *map = bvec_kmap_local(&bvec);
475 memcpy(virt, map, this_step);
476 kunmap_local(map);
477
478 bvec_iter_advance(bio->bi_io_vec, &iter, this_step);
479 to_copy -= this_step;
480 virt += this_step;
481 } while (to_copy);
482
483 __bio_add_page(clone, pages, size_to_add, 0);
484 remaining_size -= size_to_add;
485 }
486
487 return clone;
488 }
489
flakey_map(struct dm_target * ti,struct bio * bio)490 static int flakey_map(struct dm_target *ti, struct bio *bio)
491 {
492 struct flakey_c *fc = ti->private;
493 unsigned int elapsed;
494 struct per_bio_data *pb = dm_per_bio_data(bio, sizeof(struct per_bio_data));
495
496 pb->bio_can_corrupt = false;
497
498 if (op_is_zone_mgmt(bio_op(bio)))
499 goto map_bio;
500
501 /* Are we alive ? */
502 elapsed = (jiffies - fc->start_time) / HZ;
503 if (elapsed % (fc->up_interval + fc->down_interval) >= fc->up_interval) {
504 bool corrupt_fixed, corrupt_random;
505
506 if (bio_has_data(bio)) {
507 pb->bio_can_corrupt = true;
508 pb->saved_iter = bio->bi_iter;
509 }
510
511 /*
512 * If ERROR_READS isn't set flakey_end_io() will decide if the
513 * reads should be modified.
514 */
515 if (bio_data_dir(bio) == READ) {
516 if (test_bit(ERROR_READS, &fc->flags))
517 return DM_MAPIO_KILL;
518 goto map_bio;
519 }
520
521 /*
522 * Drop or error writes?
523 */
524 if (test_bit(DROP_WRITES, &fc->flags)) {
525 bio_endio(bio);
526 return DM_MAPIO_SUBMITTED;
527 } else if (test_bit(ERROR_WRITES, &fc->flags)) {
528 bio_io_error(bio);
529 return DM_MAPIO_SUBMITTED;
530 }
531
532 if (!pb->bio_can_corrupt)
533 goto map_bio;
534 /*
535 * Corrupt matching writes.
536 */
537 corrupt_fixed = false;
538 corrupt_random = false;
539 if (fc->corrupt_bio_byte && fc->corrupt_bio_rw == WRITE) {
540 if (all_corrupt_bio_flags_match(bio, fc))
541 corrupt_fixed = true;
542 }
543 if (fc->random_write_corrupt) {
544 u64 rnd = get_random_u64();
545 u32 rem = do_div(rnd, PROBABILITY_BASE);
546 if (rem < fc->random_write_corrupt)
547 corrupt_random = true;
548 }
549 if (corrupt_fixed || corrupt_random) {
550 struct bio *clone = clone_bio(ti, fc, bio);
551 if (clone) {
552 if (corrupt_fixed)
553 corrupt_bio_data(clone, fc,
554 clone->bi_iter);
555 if (corrupt_random)
556 corrupt_bio_random(clone,
557 clone->bi_iter);
558 submit_bio(clone);
559 return DM_MAPIO_SUBMITTED;
560 }
561 }
562 }
563
564 map_bio:
565 flakey_map_bio(ti, bio);
566
567 return DM_MAPIO_REMAPPED;
568 }
569
flakey_end_io(struct dm_target * ti,struct bio * bio,blk_status_t * error)570 static int flakey_end_io(struct dm_target *ti, struct bio *bio,
571 blk_status_t *error)
572 {
573 struct flakey_c *fc = ti->private;
574 struct per_bio_data *pb = dm_per_bio_data(bio, sizeof(struct per_bio_data));
575
576 if (op_is_zone_mgmt(bio_op(bio)))
577 return DM_ENDIO_DONE;
578
579 if (!*error && pb->bio_can_corrupt && (bio_data_dir(bio) == READ)) {
580 if (fc->corrupt_bio_byte) {
581 if ((fc->corrupt_bio_rw == READ) &&
582 all_corrupt_bio_flags_match(bio, fc)) {
583 /*
584 * Corrupt successful matching READs while in down state.
585 */
586 corrupt_bio_data(bio, fc, pb->saved_iter);
587 }
588 }
589 if (fc->random_read_corrupt) {
590 u64 rnd = get_random_u64();
591 u32 rem = do_div(rnd, PROBABILITY_BASE);
592 if (rem < fc->random_read_corrupt)
593 corrupt_bio_random(bio, pb->saved_iter);
594 }
595 }
596
597 return DM_ENDIO_DONE;
598 }
599
flakey_status(struct dm_target * ti,status_type_t type,unsigned int status_flags,char * result,unsigned int maxlen)600 static void flakey_status(struct dm_target *ti, status_type_t type,
601 unsigned int status_flags, char *result, unsigned int maxlen)
602 {
603 unsigned int sz = 0;
604 struct flakey_c *fc = ti->private;
605 unsigned int error_reads, drop_writes, error_writes;
606
607 switch (type) {
608 case STATUSTYPE_INFO:
609 result[0] = '\0';
610 break;
611
612 case STATUSTYPE_TABLE:
613 DMEMIT("%s %llu %u %u", fc->dev->name,
614 (unsigned long long)fc->start, fc->up_interval,
615 fc->down_interval);
616
617 error_reads = test_bit(ERROR_READS, &fc->flags);
618 drop_writes = test_bit(DROP_WRITES, &fc->flags);
619 error_writes = test_bit(ERROR_WRITES, &fc->flags);
620 DMEMIT(" %u", error_reads + drop_writes + error_writes +
621 (fc->corrupt_bio_byte > 0) * 5 +
622 (fc->random_read_corrupt > 0) * 2 +
623 (fc->random_write_corrupt > 0) * 2);
624
625 if (error_reads)
626 DMEMIT(" error_reads");
627 if (drop_writes)
628 DMEMIT(" drop_writes");
629 else if (error_writes)
630 DMEMIT(" error_writes");
631
632 if (fc->corrupt_bio_byte)
633 DMEMIT(" corrupt_bio_byte %u %c %u %u",
634 fc->corrupt_bio_byte,
635 (fc->corrupt_bio_rw == WRITE) ? 'w' : 'r',
636 fc->corrupt_bio_value, fc->corrupt_bio_flags);
637
638 if (fc->random_read_corrupt > 0)
639 DMEMIT(" random_read_corrupt %u", fc->random_read_corrupt);
640 if (fc->random_write_corrupt > 0)
641 DMEMIT(" random_write_corrupt %u", fc->random_write_corrupt);
642
643 break;
644
645 case STATUSTYPE_IMA:
646 result[0] = '\0';
647 break;
648 }
649 }
650
flakey_prepare_ioctl(struct dm_target * ti,struct block_device ** bdev,unsigned int cmd,unsigned long arg,bool * forward)651 static int flakey_prepare_ioctl(struct dm_target *ti, struct block_device **bdev,
652 unsigned int cmd, unsigned long arg,
653 bool *forward)
654 {
655 struct flakey_c *fc = ti->private;
656
657 *bdev = fc->dev->bdev;
658
659 /*
660 * Only pass ioctls through if the device sizes match exactly.
661 */
662 if (fc->start || ti->len != bdev_nr_sectors((*bdev)))
663 return 1;
664 return 0;
665 }
666
667 #ifdef CONFIG_BLK_DEV_ZONED
flakey_report_zones(struct dm_target * ti,struct dm_report_zones_args * args,unsigned int nr_zones)668 static int flakey_report_zones(struct dm_target *ti,
669 struct dm_report_zones_args *args, unsigned int nr_zones)
670 {
671 struct flakey_c *fc = ti->private;
672
673 return dm_report_zones(fc->dev->bdev, fc->start,
674 flakey_map_sector(ti, args->next_sector),
675 args, nr_zones);
676 }
677 #else
678 #define flakey_report_zones NULL
679 #endif
680
flakey_iterate_devices(struct dm_target * ti,iterate_devices_callout_fn fn,void * data)681 static int flakey_iterate_devices(struct dm_target *ti, iterate_devices_callout_fn fn, void *data)
682 {
683 struct flakey_c *fc = ti->private;
684
685 return fn(ti, fc->dev, fc->start, ti->len, data);
686 }
687
688 static struct target_type flakey_target = {
689 .name = "flakey",
690 .version = {1, 5, 0},
691 .features = DM_TARGET_ZONED_HM | DM_TARGET_PASSES_CRYPTO,
692 .report_zones = flakey_report_zones,
693 .module = THIS_MODULE,
694 .ctr = flakey_ctr,
695 .dtr = flakey_dtr,
696 .map = flakey_map,
697 .end_io = flakey_end_io,
698 .status = flakey_status,
699 .prepare_ioctl = flakey_prepare_ioctl,
700 .iterate_devices = flakey_iterate_devices,
701 };
702 module_dm(flakey);
703
704 MODULE_DESCRIPTION(DM_NAME " flakey target");
705 MODULE_AUTHOR("Joe Thornber <dm-devel@lists.linux.dev>");
706 MODULE_LICENSE("GPL");
707