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3bd94003 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
3407ef52 JB |
2 | /* |
3 | * Copyright (C) 2003 Sistina Software (UK) Limited. | |
a3998799 | 4 | * Copyright (C) 2004, 2010-2011 Red Hat, Inc. All rights reserved. |
3407ef52 JB |
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 | ||
4c2c845b MP |
19 | #define PROBABILITY_BASE 1000000000 |
20 | ||
a3998799 | 21 | #define all_corrupt_bio_flags_match(bio, fc) \ |
1eff9d32 | 22 | (((bio)->bi_opf & (fc)->corrupt_bio_flags) == (fc)->corrupt_bio_flags) |
a3998799 | 23 | |
3407ef52 JB |
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; | |
86a3238c HM |
32 | unsigned int up_interval; |
33 | unsigned int down_interval; | |
b26f5e3d | 34 | unsigned long flags; |
86a3238c HM |
35 | unsigned int corrupt_bio_byte; |
36 | unsigned int corrupt_bio_rw; | |
37 | unsigned int corrupt_bio_value; | |
eff17e51 | 38 | blk_opf_t corrupt_bio_flags; |
4c2c845b MP |
39 | unsigned int random_read_corrupt; |
40 | unsigned int random_write_corrupt; | |
3407ef52 JB |
41 | }; |
42 | ||
b26f5e3d | 43 | enum feature_flag_bits { |
aa7d7bc9 | 44 | ERROR_READS, |
ef548c55 MS |
45 | DROP_WRITES, |
46 | ERROR_WRITES | |
b26f5e3d MS |
47 | }; |
48 | ||
c7cfdf59 MP |
49 | struct per_bio_data { |
50 | bool bio_submitted; | |
51 | }; | |
52 | ||
b26f5e3d MS |
53 | static int parse_features(struct dm_arg_set *as, struct flakey_c *fc, |
54 | struct dm_target *ti) | |
dfd068b0 MS |
55 | { |
56 | int r; | |
86a3238c | 57 | unsigned int argc; |
dfd068b0 MS |
58 | const char *arg_name; |
59 | ||
5916a22b | 60 | static const struct dm_arg _args[] = { |
4c2c845b | 61 | {0, 11, "Invalid number of feature args"}, |
a3998799 MS |
62 | {1, UINT_MAX, "Invalid corrupt bio byte"}, |
63 | {0, 255, "Invalid corrupt value to write into bio byte (0-255)"}, | |
64 | {0, UINT_MAX, "Invalid corrupt bio flags mask"}, | |
4c2c845b | 65 | {0, PROBABILITY_BASE, "Invalid random corrupt argument"}, |
dfd068b0 MS |
66 | }; |
67 | ||
68 | /* No feature arguments supplied. */ | |
69 | if (!as->argc) | |
70 | return 0; | |
71 | ||
72 | r = dm_read_arg_group(_args, as, &argc, &ti->error); | |
73 | if (r) | |
a3998799 | 74 | return r; |
dfd068b0 | 75 | |
a3998799 | 76 | while (argc) { |
dfd068b0 MS |
77 | arg_name = dm_shift_arg(as); |
78 | argc--; | |
79 | ||
7690e253 GR |
80 | if (!arg_name) { |
81 | ti->error = "Insufficient feature arguments"; | |
82 | return -EINVAL; | |
83 | } | |
84 | ||
aa7d7bc9 MP |
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 | ||
b26f5e3d MS |
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; | |
ef548c55 MS |
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; | |
b26f5e3d MS |
122 | } |
123 | ||
124 | continue; | |
125 | } | |
126 | ||
a3998799 MS |
127 | /* |
128 | * corrupt_bio_byte <Nth_byte> <direction> <value> <bio_flags> | |
129 | */ | |
130 | if (!strcasecmp(arg_name, "corrupt_bio_byte")) { | |
68e58a29 | 131 | if (!argc) { |
a3998799 | 132 | ti->error = "Feature corrupt_bio_byte requires parameters"; |
68e58a29 MS |
133 | return -EINVAL; |
134 | } | |
a3998799 MS |
135 | |
136 | r = dm_read_arg(_args + 1, as, &fc->corrupt_bio_byte, &ti->error); | |
137 | if (r) | |
138 | return r; | |
139 | argc--; | |
140 | ||
141 | /* | |
142 | * Direction r or w? | |
143 | */ | |
144 | arg_name = dm_shift_arg(as); | |
98dba02d | 145 | if (arg_name && !strcasecmp(arg_name, "w")) |
a3998799 | 146 | fc->corrupt_bio_rw = WRITE; |
98dba02d | 147 | else if (arg_name && !strcasecmp(arg_name, "r")) |
a3998799 MS |
148 | fc->corrupt_bio_rw = READ; |
149 | else { | |
150 | ti->error = "Invalid corrupt bio direction (r or w)"; | |
151 | return -EINVAL; | |
152 | } | |
153 | argc--; | |
154 | ||
155 | /* | |
156 | * Value of byte (0-255) to write in place of correct one. | |
157 | */ | |
158 | r = dm_read_arg(_args + 2, as, &fc->corrupt_bio_value, &ti->error); | |
159 | if (r) | |
160 | return r; | |
161 | argc--; | |
162 | ||
163 | /* | |
164 | * Only corrupt bios with these flags set. | |
165 | */ | |
eff17e51 BVA |
166 | BUILD_BUG_ON(sizeof(fc->corrupt_bio_flags) != |
167 | sizeof(unsigned int)); | |
168 | r = dm_read_arg(_args + 3, as, | |
86a3238c | 169 | (__force unsigned int *)&fc->corrupt_bio_flags, |
eff17e51 | 170 | &ti->error); |
a3998799 MS |
171 | if (r) |
172 | return r; | |
173 | argc--; | |
174 | ||
175 | continue; | |
176 | } | |
177 | ||
4c2c845b MP |
178 | if (!strcasecmp(arg_name, "random_read_corrupt")) { |
179 | if (!argc) { | |
180 | ti->error = "Feature random_read_corrupt requires a parameter"; | |
181 | return -EINVAL; | |
182 | } | |
183 | r = dm_read_arg(_args + 4, as, &fc->random_read_corrupt, &ti->error); | |
184 | if (r) | |
185 | return r; | |
186 | argc--; | |
187 | ||
188 | continue; | |
189 | } | |
190 | ||
191 | if (!strcasecmp(arg_name, "random_write_corrupt")) { | |
192 | if (!argc) { | |
193 | ti->error = "Feature random_write_corrupt requires a parameter"; | |
194 | return -EINVAL; | |
195 | } | |
196 | r = dm_read_arg(_args + 4, as, &fc->random_write_corrupt, &ti->error); | |
197 | if (r) | |
198 | return r; | |
199 | argc--; | |
200 | ||
201 | continue; | |
202 | } | |
203 | ||
dfd068b0 | 204 | ti->error = "Unrecognised flakey feature requested"; |
a3998799 | 205 | return -EINVAL; |
dfd068b0 MS |
206 | } |
207 | ||
a3998799 MS |
208 | if (test_bit(DROP_WRITES, &fc->flags) && (fc->corrupt_bio_rw == WRITE)) { |
209 | ti->error = "drop_writes is incompatible with corrupt_bio_byte with the WRITE flag set"; | |
210 | return -EINVAL; | |
ef548c55 MS |
211 | |
212 | } else if (test_bit(ERROR_WRITES, &fc->flags) && (fc->corrupt_bio_rw == WRITE)) { | |
213 | ti->error = "error_writes is incompatible with corrupt_bio_byte with the WRITE flag set"; | |
214 | return -EINVAL; | |
a3998799 MS |
215 | } |
216 | ||
aa7d7bc9 | 217 | if (!fc->corrupt_bio_byte && !test_bit(ERROR_READS, &fc->flags) && |
4c2c845b MP |
218 | !test_bit(DROP_WRITES, &fc->flags) && !test_bit(ERROR_WRITES, &fc->flags) && |
219 | !fc->random_read_corrupt && !fc->random_write_corrupt) { | |
aa7d7bc9 MP |
220 | set_bit(ERROR_WRITES, &fc->flags); |
221 | set_bit(ERROR_READS, &fc->flags); | |
222 | } | |
223 | ||
a3998799 | 224 | return 0; |
dfd068b0 MS |
225 | } |
226 | ||
3407ef52 | 227 | /* |
dfd068b0 MS |
228 | * Construct a flakey mapping: |
229 | * <dev_path> <offset> <up interval> <down interval> [<#feature args> [<arg>]*] | |
b26f5e3d MS |
230 | * |
231 | * Feature args: | |
232 | * [drop_writes] | |
a3998799 MS |
233 | * [corrupt_bio_byte <Nth_byte> <direction> <value> <bio_flags>] |
234 | * | |
235 | * Nth_byte starts from 1 for the first byte. | |
236 | * Direction is r for READ or w for WRITE. | |
237 | * bio_flags is ignored if 0. | |
3407ef52 JB |
238 | */ |
239 | static int flakey_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
240 | { | |
5916a22b | 241 | static const struct dm_arg _args[] = { |
dfd068b0 MS |
242 | {0, UINT_MAX, "Invalid up interval"}, |
243 | {0, UINT_MAX, "Invalid down interval"}, | |
244 | }; | |
245 | ||
246 | int r; | |
3407ef52 | 247 | struct flakey_c *fc; |
dfd068b0 MS |
248 | unsigned long long tmpll; |
249 | struct dm_arg_set as; | |
250 | const char *devname; | |
31998ef1 | 251 | char dummy; |
3407ef52 | 252 | |
dfd068b0 MS |
253 | as.argc = argc; |
254 | as.argv = argv; | |
255 | ||
256 | if (argc < 4) { | |
257 | ti->error = "Invalid argument count"; | |
3407ef52 JB |
258 | return -EINVAL; |
259 | } | |
260 | ||
b26f5e3d | 261 | fc = kzalloc(sizeof(*fc), GFP_KERNEL); |
3407ef52 | 262 | if (!fc) { |
75e3a0f5 | 263 | ti->error = "Cannot allocate context"; |
3407ef52 JB |
264 | return -ENOMEM; |
265 | } | |
266 | fc->start_time = jiffies; | |
267 | ||
dfd068b0 MS |
268 | devname = dm_shift_arg(&as); |
269 | ||
e80d1c80 | 270 | r = -EINVAL; |
ef87bfc2 | 271 | if (sscanf(dm_shift_arg(&as), "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) { |
dfd068b0 | 272 | ti->error = "Invalid device sector"; |
3407ef52 JB |
273 | goto bad; |
274 | } | |
dfd068b0 | 275 | fc->start = tmpll; |
3407ef52 | 276 | |
dfd068b0 MS |
277 | r = dm_read_arg(_args, &as, &fc->up_interval, &ti->error); |
278 | if (r) | |
3407ef52 | 279 | goto bad; |
3407ef52 | 280 | |
dfd068b0 MS |
281 | r = dm_read_arg(_args, &as, &fc->down_interval, &ti->error); |
282 | if (r) | |
3407ef52 | 283 | goto bad; |
3407ef52 JB |
284 | |
285 | if (!(fc->up_interval + fc->down_interval)) { | |
dfd068b0 | 286 | ti->error = "Total (up + down) interval is zero"; |
bff7e067 | 287 | r = -EINVAL; |
3407ef52 JB |
288 | goto bad; |
289 | } | |
290 | ||
291 | if (fc->up_interval + fc->down_interval < fc->up_interval) { | |
dfd068b0 | 292 | ti->error = "Interval overflow"; |
bff7e067 | 293 | r = -EINVAL; |
3407ef52 JB |
294 | goto bad; |
295 | } | |
296 | ||
b26f5e3d | 297 | r = parse_features(&as, fc, ti); |
dfd068b0 MS |
298 | if (r) |
299 | goto bad; | |
300 | ||
e80d1c80 VG |
301 | r = dm_get_device(ti, devname, dm_table_get_mode(ti->table), &fc->dev); |
302 | if (r) { | |
dfd068b0 | 303 | ti->error = "Device lookup failed"; |
3407ef52 JB |
304 | goto bad; |
305 | } | |
306 | ||
55a62eef AK |
307 | ti->num_flush_bios = 1; |
308 | ti->num_discard_bios = 1; | |
30187e1d | 309 | ti->per_io_data_size = sizeof(struct per_bio_data); |
3407ef52 JB |
310 | ti->private = fc; |
311 | return 0; | |
312 | ||
313 | bad: | |
314 | kfree(fc); | |
e80d1c80 | 315 | return r; |
3407ef52 JB |
316 | } |
317 | ||
318 | static void flakey_dtr(struct dm_target *ti) | |
319 | { | |
320 | struct flakey_c *fc = ti->private; | |
321 | ||
322 | dm_put_device(ti, fc->dev); | |
323 | kfree(fc); | |
324 | } | |
325 | ||
326 | static sector_t flakey_map_sector(struct dm_target *ti, sector_t bi_sector) | |
327 | { | |
328 | struct flakey_c *fc = ti->private; | |
329 | ||
30e4171b | 330 | return fc->start + dm_target_offset(ti, bi_sector); |
3407ef52 JB |
331 | } |
332 | ||
333 | static void flakey_map_bio(struct dm_target *ti, struct bio *bio) | |
334 | { | |
335 | struct flakey_c *fc = ti->private; | |
336 | ||
74d46992 | 337 | bio_set_dev(bio, fc->dev->bdev); |
e86f2b00 | 338 | bio->bi_iter.bi_sector = flakey_map_sector(ti, bio->bi_iter.bi_sector); |
3407ef52 JB |
339 | } |
340 | ||
4c2c845b MP |
341 | static void corrupt_bio_common(struct bio *bio, unsigned int corrupt_bio_byte, |
342 | unsigned char corrupt_bio_value) | |
a3998799 | 343 | { |
a00f5276 ST |
344 | struct bvec_iter iter; |
345 | struct bio_vec bvec; | |
346 | ||
a3998799 | 347 | /* |
a00f5276 ST |
348 | * Overwrite the Nth byte of the bio's data, on whichever page |
349 | * it falls. | |
a3998799 | 350 | */ |
a00f5276 ST |
351 | bio_for_each_segment(bvec, bio, iter) { |
352 | if (bio_iter_len(bio, iter) > corrupt_bio_byte) { | |
4c2c845b MP |
353 | unsigned char *segment = bvec_kmap_local(&bvec); |
354 | segment[corrupt_bio_byte] = corrupt_bio_value; | |
8eb29c4f | 355 | kunmap_local(segment); |
a00f5276 ST |
356 | DMDEBUG("Corrupting data bio=%p by writing %u to byte %u " |
357 | "(rw=%c bi_opf=%u bi_sector=%llu size=%u)\n", | |
4c2c845b | 358 | bio, corrupt_bio_value, corrupt_bio_byte, |
a00f5276 | 359 | (bio_data_dir(bio) == WRITE) ? 'w' : 'r', bio->bi_opf, |
4c2c845b MP |
360 | (unsigned long long)bio->bi_iter.bi_sector, |
361 | bio->bi_iter.bi_size); | |
a00f5276 ST |
362 | break; |
363 | } | |
364 | corrupt_bio_byte -= bio_iter_len(bio, iter); | |
a3998799 MS |
365 | } |
366 | } | |
367 | ||
4c2c845b MP |
368 | static void corrupt_bio_data(struct bio *bio, struct flakey_c *fc) |
369 | { | |
370 | unsigned int corrupt_bio_byte = fc->corrupt_bio_byte - 1; | |
371 | ||
372 | if (!bio_has_data(bio)) | |
373 | return; | |
374 | ||
375 | corrupt_bio_common(bio, corrupt_bio_byte, fc->corrupt_bio_value); | |
376 | } | |
377 | ||
378 | static void corrupt_bio_random(struct bio *bio) | |
379 | { | |
380 | unsigned int corrupt_byte; | |
381 | unsigned char corrupt_value; | |
382 | ||
383 | if (!bio_has_data(bio)) | |
384 | return; | |
385 | ||
386 | corrupt_byte = get_random_u32() % bio->bi_iter.bi_size; | |
387 | corrupt_value = get_random_u8(); | |
388 | ||
389 | corrupt_bio_common(bio, corrupt_byte, corrupt_value); | |
390 | } | |
391 | ||
1d9a9438 MP |
392 | static void clone_free(struct bio *clone) |
393 | { | |
394 | struct folio_iter fi; | |
395 | ||
396 | if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */ | |
397 | bio_for_each_folio_all(fi, clone) | |
398 | folio_put(fi.folio); | |
399 | } | |
400 | ||
401 | bio_uninit(clone); | |
402 | kfree(clone); | |
403 | } | |
404 | ||
405 | static void clone_endio(struct bio *clone) | |
406 | { | |
407 | struct bio *bio = clone->bi_private; | |
408 | bio->bi_status = clone->bi_status; | |
409 | clone_free(clone); | |
410 | bio_endio(bio); | |
411 | } | |
412 | ||
413 | static struct bio *clone_bio(struct dm_target *ti, struct flakey_c *fc, struct bio *bio) | |
414 | { | |
415 | struct bio *clone; | |
416 | unsigned size, remaining_size, nr_iovecs, order; | |
417 | struct bvec_iter iter = bio->bi_iter; | |
418 | ||
419 | if (unlikely(bio->bi_iter.bi_size > UIO_MAXIOV << PAGE_SHIFT)) | |
420 | dm_accept_partial_bio(bio, UIO_MAXIOV << PAGE_SHIFT >> SECTOR_SHIFT); | |
421 | ||
422 | size = bio->bi_iter.bi_size; | |
423 | nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
424 | ||
425 | clone = bio_kmalloc(nr_iovecs, GFP_NOIO | __GFP_NORETRY | __GFP_NOWARN); | |
426 | if (!clone) | |
427 | return NULL; | |
428 | ||
429 | bio_init(clone, fc->dev->bdev, bio->bi_inline_vecs, nr_iovecs, bio->bi_opf); | |
430 | ||
431 | clone->bi_iter.bi_sector = flakey_map_sector(ti, bio->bi_iter.bi_sector); | |
432 | clone->bi_private = bio; | |
433 | clone->bi_end_io = clone_endio; | |
434 | ||
435 | remaining_size = size; | |
436 | ||
41e05548 | 437 | order = MAX_ORDER; |
1d9a9438 MP |
438 | while (remaining_size) { |
439 | struct page *pages; | |
440 | unsigned size_to_add, to_copy; | |
441 | unsigned char *virt; | |
442 | unsigned remaining_order = __fls((remaining_size + PAGE_SIZE - 1) >> PAGE_SHIFT); | |
443 | order = min(order, remaining_order); | |
444 | ||
445 | retry_alloc_pages: | |
446 | pages = alloc_pages(GFP_NOIO | __GFP_NORETRY | __GFP_NOWARN | __GFP_COMP, order); | |
447 | if (unlikely(!pages)) { | |
448 | if (order) { | |
449 | order--; | |
450 | goto retry_alloc_pages; | |
451 | } | |
452 | clone_free(clone); | |
453 | return NULL; | |
454 | } | |
455 | size_to_add = min((unsigned)PAGE_SIZE << order, remaining_size); | |
456 | ||
457 | virt = page_to_virt(pages); | |
458 | to_copy = size_to_add; | |
459 | do { | |
460 | struct bio_vec bvec = bvec_iter_bvec(bio->bi_io_vec, iter); | |
461 | unsigned this_step = min(bvec.bv_len, to_copy); | |
462 | void *map = bvec_kmap_local(&bvec); | |
463 | memcpy(virt, map, this_step); | |
464 | kunmap_local(map); | |
465 | ||
466 | bvec_iter_advance(bio->bi_io_vec, &iter, this_step); | |
467 | to_copy -= this_step; | |
468 | virt += this_step; | |
469 | } while (to_copy); | |
470 | ||
471 | __bio_add_page(clone, pages, size_to_add, 0); | |
472 | remaining_size -= size_to_add; | |
473 | } | |
474 | ||
475 | return clone; | |
476 | } | |
477 | ||
7de3ee57 | 478 | static int flakey_map(struct dm_target *ti, struct bio *bio) |
3407ef52 JB |
479 | { |
480 | struct flakey_c *fc = ti->private; | |
86a3238c | 481 | unsigned int elapsed; |
c7cfdf59 | 482 | struct per_bio_data *pb = dm_per_bio_data(bio, sizeof(struct per_bio_data)); |
0ef0b471 | 483 | |
c7cfdf59 | 484 | pb->bio_submitted = false; |
3407ef52 | 485 | |
2e2d6f7e | 486 | if (op_is_zone_mgmt(bio_op(bio))) |
124c4454 DLM |
487 | goto map_bio; |
488 | ||
3407ef52 JB |
489 | /* Are we alive ? */ |
490 | elapsed = (jiffies - fc->start_time) / HZ; | |
b26f5e3d | 491 | if (elapsed % (fc->up_interval + fc->down_interval) >= fc->up_interval) { |
4c2c845b | 492 | bool corrupt_fixed, corrupt_random; |
a3998799 MS |
493 | /* |
494 | * Flag this bio as submitted while down. | |
495 | */ | |
c7cfdf59 | 496 | pb->bio_submitted = true; |
a3998799 MS |
497 | |
498 | /* | |
ef548c55 | 499 | * Error reads if neither corrupt_bio_byte or drop_writes or error_writes are set. |
299f6230 | 500 | * Otherwise, flakey_end_io() will decide if the reads should be modified. |
a3998799 | 501 | */ |
99f3c90d | 502 | if (bio_data_dir(bio) == READ) { |
aa7d7bc9 | 503 | if (test_bit(ERROR_READS, &fc->flags)) |
846785e6 | 504 | return DM_MAPIO_KILL; |
299f6230 | 505 | goto map_bio; |
99f3c90d | 506 | } |
b26f5e3d MS |
507 | |
508 | /* | |
ef548c55 | 509 | * Drop or error writes? |
b26f5e3d MS |
510 | */ |
511 | if (test_bit(DROP_WRITES, &fc->flags)) { | |
4246a0b6 | 512 | bio_endio(bio); |
a3998799 | 513 | return DM_MAPIO_SUBMITTED; |
03b18887 | 514 | } else if (test_bit(ERROR_WRITES, &fc->flags)) { |
ef548c55 MS |
515 | bio_io_error(bio); |
516 | return DM_MAPIO_SUBMITTED; | |
517 | } | |
a3998799 MS |
518 | |
519 | /* | |
520 | * Corrupt matching writes. | |
521 | */ | |
4c2c845b MP |
522 | corrupt_fixed = false; |
523 | corrupt_random = false; | |
1d9a9438 | 524 | if (fc->corrupt_bio_byte && fc->corrupt_bio_rw == WRITE) { |
4c2c845b MP |
525 | if (all_corrupt_bio_flags_match(bio, fc)) |
526 | corrupt_fixed = true; | |
527 | } | |
528 | if (fc->random_write_corrupt) { | |
529 | u64 rnd = get_random_u64(); | |
530 | u32 rem = do_div(rnd, PROBABILITY_BASE); | |
531 | if (rem < fc->random_write_corrupt) | |
532 | corrupt_random = true; | |
533 | } | |
534 | if (corrupt_fixed || corrupt_random) { | |
535 | struct bio *clone = clone_bio(ti, fc, bio); | |
536 | if (clone) { | |
537 | if (corrupt_fixed) | |
1d9a9438 | 538 | corrupt_bio_data(clone, fc); |
4c2c845b MP |
539 | if (corrupt_random) |
540 | corrupt_bio_random(clone); | |
541 | submit_bio(clone); | |
542 | return DM_MAPIO_SUBMITTED; | |
aa56b9b7 | 543 | } |
b26f5e3d | 544 | } |
b26f5e3d | 545 | } |
3407ef52 | 546 | |
b26f5e3d | 547 | map_bio: |
3407ef52 JB |
548 | flakey_map_bio(ti, bio); |
549 | ||
550 | return DM_MAPIO_REMAPPED; | |
551 | } | |
552 | ||
4e4cbee9 | 553 | static int flakey_end_io(struct dm_target *ti, struct bio *bio, |
124c4454 | 554 | blk_status_t *error) |
a3998799 MS |
555 | { |
556 | struct flakey_c *fc = ti->private; | |
c7cfdf59 | 557 | struct per_bio_data *pb = dm_per_bio_data(bio, sizeof(struct per_bio_data)); |
a3998799 | 558 | |
2e2d6f7e | 559 | if (op_is_zone_mgmt(bio_op(bio))) |
124c4454 DLM |
560 | return DM_ENDIO_DONE; |
561 | ||
1be56909 | 562 | if (!*error && pb->bio_submitted && (bio_data_dir(bio) == READ)) { |
aa56b9b7 MP |
563 | if (fc->corrupt_bio_byte) { |
564 | if ((fc->corrupt_bio_rw == READ) && | |
565 | all_corrupt_bio_flags_match(bio, fc)) { | |
566 | /* | |
567 | * Corrupt successful matching READs while in down state. | |
568 | */ | |
569 | corrupt_bio_data(bio, fc); | |
570 | } | |
aa7d7bc9 | 571 | } |
4c2c845b MP |
572 | if (fc->random_read_corrupt) { |
573 | u64 rnd = get_random_u64(); | |
574 | u32 rem = do_div(rnd, PROBABILITY_BASE); | |
575 | if (rem < fc->random_read_corrupt) | |
576 | corrupt_bio_random(bio); | |
577 | } | |
aa7d7bc9 | 578 | if (test_bit(ERROR_READS, &fc->flags)) { |
299f6230 MS |
579 | /* |
580 | * Error read during the down_interval if drop_writes | |
ef548c55 | 581 | * and error_writes were not configured. |
299f6230 | 582 | */ |
4e4cbee9 | 583 | *error = BLK_STS_IOERR; |
299f6230 | 584 | } |
99f3c90d | 585 | } |
a3998799 | 586 | |
1be56909 | 587 | return DM_ENDIO_DONE; |
a3998799 MS |
588 | } |
589 | ||
fd7c092e | 590 | static void flakey_status(struct dm_target *ti, status_type_t type, |
86a3238c | 591 | unsigned int status_flags, char *result, unsigned int maxlen) |
3407ef52 | 592 | { |
86a3238c | 593 | unsigned int sz = 0; |
3407ef52 | 594 | struct flakey_c *fc = ti->private; |
aa7d7bc9 | 595 | unsigned int error_reads, drop_writes, error_writes; |
3407ef52 JB |
596 | |
597 | switch (type) { | |
598 | case STATUSTYPE_INFO: | |
599 | result[0] = '\0'; | |
600 | break; | |
601 | ||
602 | case STATUSTYPE_TABLE: | |
e3675dc1 | 603 | DMEMIT("%s %llu %u %u", fc->dev->name, |
b26f5e3d MS |
604 | (unsigned long long)fc->start, fc->up_interval, |
605 | fc->down_interval); | |
606 | ||
aa7d7bc9 | 607 | error_reads = test_bit(ERROR_READS, &fc->flags); |
b26f5e3d | 608 | drop_writes = test_bit(DROP_WRITES, &fc->flags); |
ef548c55 | 609 | error_writes = test_bit(ERROR_WRITES, &fc->flags); |
4c2c845b MP |
610 | DMEMIT(" %u", error_reads + drop_writes + error_writes + |
611 | (fc->corrupt_bio_byte > 0) * 5 + | |
612 | (fc->random_read_corrupt > 0) * 2 + | |
613 | (fc->random_write_corrupt > 0) * 2); | |
a3998799 | 614 | |
aa7d7bc9 MP |
615 | if (error_reads) |
616 | DMEMIT(" error_reads"); | |
b26f5e3d | 617 | if (drop_writes) |
e3675dc1 | 618 | DMEMIT(" drop_writes"); |
ef548c55 | 619 | else if (error_writes) |
e3675dc1 | 620 | DMEMIT(" error_writes"); |
a3998799 MS |
621 | |
622 | if (fc->corrupt_bio_byte) | |
e3675dc1 | 623 | DMEMIT(" corrupt_bio_byte %u %c %u %u", |
a3998799 MS |
624 | fc->corrupt_bio_byte, |
625 | (fc->corrupt_bio_rw == WRITE) ? 'w' : 'r', | |
626 | fc->corrupt_bio_value, fc->corrupt_bio_flags); | |
627 | ||
4c2c845b MP |
628 | if (fc->random_read_corrupt > 0) |
629 | DMEMIT(" random_read_corrupt %u", fc->random_read_corrupt); | |
630 | if (fc->random_write_corrupt > 0) | |
631 | DMEMIT(" random_write_corrupt %u", fc->random_write_corrupt); | |
632 | ||
3407ef52 | 633 | break; |
8ec45662 TS |
634 | |
635 | case STATUSTYPE_IMA: | |
636 | result[0] = '\0'; | |
637 | break; | |
3407ef52 | 638 | } |
3407ef52 JB |
639 | } |
640 | ||
5bd5e8d8 | 641 | static int flakey_prepare_ioctl(struct dm_target *ti, struct block_device **bdev) |
3407ef52 JB |
642 | { |
643 | struct flakey_c *fc = ti->private; | |
e56f81e0 CH |
644 | |
645 | *bdev = fc->dev->bdev; | |
3407ef52 | 646 | |
ec8013be PB |
647 | /* |
648 | * Only pass ioctls through if the device sizes match exactly. | |
649 | */ | |
6dcbb52c | 650 | if (fc->start || ti->len != bdev_nr_sectors((*bdev))) |
e56f81e0 CH |
651 | return 1; |
652 | return 0; | |
3407ef52 JB |
653 | } |
654 | ||
e76239a3 | 655 | #ifdef CONFIG_BLK_DEV_ZONED |
d4100351 CH |
656 | static int flakey_report_zones(struct dm_target *ti, |
657 | struct dm_report_zones_args *args, unsigned int nr_zones) | |
e76239a3 CH |
658 | { |
659 | struct flakey_c *fc = ti->private; | |
e76239a3 | 660 | |
912e8875 DLM |
661 | return dm_report_zones(fc->dev->bdev, fc->start, |
662 | flakey_map_sector(ti, args->next_sector), | |
663 | args, nr_zones); | |
e76239a3 | 664 | } |
e3290b94 MS |
665 | #else |
666 | #define flakey_report_zones NULL | |
e76239a3 CH |
667 | #endif |
668 | ||
3407ef52 JB |
669 | static int flakey_iterate_devices(struct dm_target *ti, iterate_devices_callout_fn fn, void *data) |
670 | { | |
671 | struct flakey_c *fc = ti->private; | |
672 | ||
673 | return fn(ti, fc->dev, fc->start, ti->len, data); | |
674 | } | |
675 | ||
676 | static struct target_type flakey_target = { | |
677 | .name = "flakey", | |
124c4454 | 678 | .version = {1, 5, 0}, |
3db564b4 | 679 | .features = DM_TARGET_ZONED_HM | DM_TARGET_PASSES_CRYPTO, |
e76239a3 | 680 | .report_zones = flakey_report_zones, |
3407ef52 JB |
681 | .module = THIS_MODULE, |
682 | .ctr = flakey_ctr, | |
683 | .dtr = flakey_dtr, | |
684 | .map = flakey_map, | |
a3998799 | 685 | .end_io = flakey_end_io, |
3407ef52 | 686 | .status = flakey_status, |
e56f81e0 | 687 | .prepare_ioctl = flakey_prepare_ioctl, |
3407ef52 JB |
688 | .iterate_devices = flakey_iterate_devices, |
689 | }; | |
3664ff82 | 690 | module_dm(flakey); |
3407ef52 JB |
691 | |
692 | MODULE_DESCRIPTION(DM_NAME " flakey target"); | |
693 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); | |
694 | MODULE_LICENSE("GPL"); |