1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (c) International Business Machines Corp., 2006 4 * 5 * Author: Artem Bityutskiy (Битюцкий Артём) 6 */ 7 8 #include "ubi.h" 9 #include <linux/debugfs.h> 10 #include <linux/uaccess.h> 11 #include <linux/module.h> 12 #include <linux/seq_file.h> 13 14 15 /** 16 * ubi_dump_flash - dump a region of flash. 17 * @ubi: UBI device description object 18 * @pnum: the physical eraseblock number to dump 19 * @offset: the starting offset within the physical eraseblock to dump 20 * @len: the length of the region to dump 21 */ 22 void ubi_dump_flash(struct ubi_device *ubi, int pnum, int offset, int len) 23 { 24 int err; 25 size_t read; 26 void *buf; 27 loff_t addr = (loff_t)pnum * ubi->peb_size + offset; 28 29 buf = vmalloc(len); 30 if (!buf) 31 return; 32 err = mtd_read(ubi->mtd, addr, len, &read, buf); 33 if (err && err != -EUCLEAN) { 34 ubi_err(ubi, "err %d while reading %d bytes from PEB %d:%d, read %zd bytes", 35 err, len, pnum, offset, read); 36 goto out; 37 } 38 39 ubi_msg(ubi, "dumping %d bytes of data from PEB %d, offset %d", 40 len, pnum, offset); 41 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, buf, len, 1); 42 out: 43 vfree(buf); 44 return; 45 } 46 47 /** 48 * ubi_dump_ec_hdr - dump an erase counter header. 49 * @ec_hdr: the erase counter header to dump 50 */ 51 void ubi_dump_ec_hdr(const struct ubi_ec_hdr *ec_hdr) 52 { 53 pr_err("Erase counter header dump:\n"); 54 pr_err("\tmagic %#08x\n", be32_to_cpu(ec_hdr->magic)); 55 pr_err("\tversion %d\n", (int)ec_hdr->version); 56 pr_err("\tec %llu\n", (long long)be64_to_cpu(ec_hdr->ec)); 57 pr_err("\tvid_hdr_offset %d\n", be32_to_cpu(ec_hdr->vid_hdr_offset)); 58 pr_err("\tdata_offset %d\n", be32_to_cpu(ec_hdr->data_offset)); 59 pr_err("\timage_seq %d\n", be32_to_cpu(ec_hdr->image_seq)); 60 pr_err("\thdr_crc %#08x\n", be32_to_cpu(ec_hdr->hdr_crc)); 61 pr_err("erase counter header hexdump:\n"); 62 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, 63 ec_hdr, UBI_EC_HDR_SIZE, 1); 64 } 65 66 /** 67 * ubi_dump_vid_hdr - dump a volume identifier header. 68 * @vid_hdr: the volume identifier header to dump 69 */ 70 void ubi_dump_vid_hdr(const struct ubi_vid_hdr *vid_hdr) 71 { 72 pr_err("Volume identifier header dump:\n"); 73 pr_err("\tmagic %08x\n", be32_to_cpu(vid_hdr->magic)); 74 pr_err("\tversion %d\n", (int)vid_hdr->version); 75 pr_err("\tvol_type %d\n", (int)vid_hdr->vol_type); 76 pr_err("\tcopy_flag %d\n", (int)vid_hdr->copy_flag); 77 pr_err("\tcompat %d\n", (int)vid_hdr->compat); 78 pr_err("\tvol_id %d\n", be32_to_cpu(vid_hdr->vol_id)); 79 pr_err("\tlnum %d\n", be32_to_cpu(vid_hdr->lnum)); 80 pr_err("\tdata_size %d\n", be32_to_cpu(vid_hdr->data_size)); 81 pr_err("\tused_ebs %d\n", be32_to_cpu(vid_hdr->used_ebs)); 82 pr_err("\tdata_pad %d\n", be32_to_cpu(vid_hdr->data_pad)); 83 pr_err("\tsqnum %llu\n", 84 (unsigned long long)be64_to_cpu(vid_hdr->sqnum)); 85 pr_err("\thdr_crc %08x\n", be32_to_cpu(vid_hdr->hdr_crc)); 86 pr_err("Volume identifier header hexdump:\n"); 87 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, 88 vid_hdr, UBI_VID_HDR_SIZE, 1); 89 } 90 91 /** 92 * ubi_dump_vol_info - dump volume information. 93 * @vol: UBI volume description object 94 */ 95 void ubi_dump_vol_info(const struct ubi_volume *vol) 96 { 97 pr_err("Volume information dump:\n"); 98 pr_err("\tvol_id %d\n", vol->vol_id); 99 pr_err("\treserved_pebs %d\n", vol->reserved_pebs); 100 pr_err("\talignment %d\n", vol->alignment); 101 pr_err("\tdata_pad %d\n", vol->data_pad); 102 pr_err("\tvol_type %d\n", vol->vol_type); 103 pr_err("\tname_len %d\n", vol->name_len); 104 pr_err("\tusable_leb_size %d\n", vol->usable_leb_size); 105 pr_err("\tused_ebs %d\n", vol->used_ebs); 106 pr_err("\tused_bytes %lld\n", vol->used_bytes); 107 pr_err("\tlast_eb_bytes %d\n", vol->last_eb_bytes); 108 pr_err("\tcorrupted %d\n", vol->corrupted); 109 pr_err("\tupd_marker %d\n", vol->upd_marker); 110 111 if (vol->name_len <= UBI_VOL_NAME_MAX && 112 strnlen(vol->name, vol->name_len + 1) == vol->name_len) { 113 pr_err("\tname %s\n", vol->name); 114 } else { 115 pr_err("\t1st 5 characters of name: %c%c%c%c%c\n", 116 vol->name[0], vol->name[1], vol->name[2], 117 vol->name[3], vol->name[4]); 118 } 119 } 120 121 /** 122 * ubi_dump_vtbl_record - dump a &struct ubi_vtbl_record object. 123 * @r: the object to dump 124 * @idx: volume table index 125 */ 126 void ubi_dump_vtbl_record(const struct ubi_vtbl_record *r, int idx) 127 { 128 int name_len = be16_to_cpu(r->name_len); 129 130 pr_err("Volume table record %d dump:\n", idx); 131 pr_err("\treserved_pebs %d\n", be32_to_cpu(r->reserved_pebs)); 132 pr_err("\talignment %d\n", be32_to_cpu(r->alignment)); 133 pr_err("\tdata_pad %d\n", be32_to_cpu(r->data_pad)); 134 pr_err("\tvol_type %d\n", (int)r->vol_type); 135 pr_err("\tupd_marker %d\n", (int)r->upd_marker); 136 pr_err("\tname_len %d\n", name_len); 137 138 if (r->name[0] == '\0') { 139 pr_err("\tname NULL\n"); 140 return; 141 } 142 143 if (name_len <= UBI_VOL_NAME_MAX && 144 strnlen(&r->name[0], name_len + 1) == name_len) { 145 pr_err("\tname %s\n", &r->name[0]); 146 } else { 147 pr_err("\t1st 5 characters of name: %c%c%c%c%c\n", 148 r->name[0], r->name[1], r->name[2], r->name[3], 149 r->name[4]); 150 } 151 pr_err("\tcrc %#08x\n", be32_to_cpu(r->crc)); 152 } 153 154 /** 155 * ubi_dump_av - dump a &struct ubi_ainf_volume object. 156 * @av: the object to dump 157 */ 158 void ubi_dump_av(const struct ubi_ainf_volume *av) 159 { 160 pr_err("Volume attaching information dump:\n"); 161 pr_err("\tvol_id %d\n", av->vol_id); 162 pr_err("\thighest_lnum %d\n", av->highest_lnum); 163 pr_err("\tleb_count %d\n", av->leb_count); 164 pr_err("\tcompat %d\n", av->compat); 165 pr_err("\tvol_type %d\n", av->vol_type); 166 pr_err("\tused_ebs %d\n", av->used_ebs); 167 pr_err("\tlast_data_size %d\n", av->last_data_size); 168 pr_err("\tdata_pad %d\n", av->data_pad); 169 } 170 171 /** 172 * ubi_dump_aeb - dump a &struct ubi_ainf_peb object. 173 * @aeb: the object to dump 174 * @type: object type: 0 - not corrupted, 1 - corrupted 175 */ 176 void ubi_dump_aeb(const struct ubi_ainf_peb *aeb, int type) 177 { 178 pr_err("eraseblock attaching information dump:\n"); 179 pr_err("\tec %d\n", aeb->ec); 180 pr_err("\tpnum %d\n", aeb->pnum); 181 if (type == 0) { 182 pr_err("\tlnum %d\n", aeb->lnum); 183 pr_err("\tscrub %d\n", aeb->scrub); 184 pr_err("\tsqnum %llu\n", aeb->sqnum); 185 } 186 } 187 188 /** 189 * ubi_dump_mkvol_req - dump a &struct ubi_mkvol_req object. 190 * @req: the object to dump 191 */ 192 void ubi_dump_mkvol_req(const struct ubi_mkvol_req *req) 193 { 194 char nm[17]; 195 196 pr_err("Volume creation request dump:\n"); 197 pr_err("\tvol_id %d\n", req->vol_id); 198 pr_err("\talignment %d\n", req->alignment); 199 pr_err("\tbytes %lld\n", (long long)req->bytes); 200 pr_err("\tvol_type %d\n", req->vol_type); 201 pr_err("\tname_len %d\n", req->name_len); 202 203 memcpy(nm, req->name, 16); 204 nm[16] = 0; 205 pr_err("\t1st 16 characters of name: %s\n", nm); 206 } 207 208 /* 209 * Root directory for UBI stuff in debugfs. Contains sub-directories which 210 * contain the stuff specific to particular UBI devices. 211 */ 212 static struct dentry *dfs_rootdir; 213 214 /** 215 * ubi_debugfs_init - create UBI debugfs directory. 216 * 217 * Create UBI debugfs directory. Returns zero in case of success and a negative 218 * error code in case of failure. 219 */ 220 int ubi_debugfs_init(void) 221 { 222 if (!IS_ENABLED(CONFIG_DEBUG_FS)) 223 return 0; 224 225 dfs_rootdir = debugfs_create_dir("ubi", NULL); 226 if (IS_ERR_OR_NULL(dfs_rootdir)) { 227 int err = dfs_rootdir ? PTR_ERR(dfs_rootdir) : -ENODEV; 228 229 pr_err("UBI error: cannot create \"ubi\" debugfs directory, error %d\n", 230 err); 231 return err; 232 } 233 234 return 0; 235 } 236 237 /** 238 * ubi_debugfs_exit - remove UBI debugfs directory. 239 */ 240 void ubi_debugfs_exit(void) 241 { 242 if (IS_ENABLED(CONFIG_DEBUG_FS)) 243 debugfs_remove(dfs_rootdir); 244 } 245 246 /* Read an UBI debugfs file */ 247 static ssize_t dfs_file_read(struct file *file, char __user *user_buf, 248 size_t count, loff_t *ppos) 249 { 250 unsigned long ubi_num = (unsigned long)file->private_data; 251 struct dentry *dent = file->f_path.dentry; 252 struct ubi_device *ubi; 253 struct ubi_debug_info *d; 254 char buf[8]; 255 int val; 256 257 ubi = ubi_get_device(ubi_num); 258 if (!ubi) 259 return -ENODEV; 260 d = &ubi->dbg; 261 262 if (dent == d->dfs_chk_gen) 263 val = d->chk_gen; 264 else if (dent == d->dfs_chk_io) 265 val = d->chk_io; 266 else if (dent == d->dfs_chk_fastmap) 267 val = d->chk_fastmap; 268 else if (dent == d->dfs_disable_bgt) 269 val = d->disable_bgt; 270 else if (dent == d->dfs_emulate_bitflips) 271 val = d->emulate_bitflips; 272 else if (dent == d->dfs_emulate_io_failures) 273 val = d->emulate_io_failures; 274 else if (dent == d->dfs_emulate_power_cut) { 275 snprintf(buf, sizeof(buf), "%u\n", d->emulate_power_cut); 276 count = simple_read_from_buffer(user_buf, count, ppos, 277 buf, strlen(buf)); 278 goto out; 279 } else if (dent == d->dfs_power_cut_min) { 280 snprintf(buf, sizeof(buf), "%u\n", d->power_cut_min); 281 count = simple_read_from_buffer(user_buf, count, ppos, 282 buf, strlen(buf)); 283 goto out; 284 } else if (dent == d->dfs_power_cut_max) { 285 snprintf(buf, sizeof(buf), "%u\n", d->power_cut_max); 286 count = simple_read_from_buffer(user_buf, count, ppos, 287 buf, strlen(buf)); 288 goto out; 289 } 290 else { 291 count = -EINVAL; 292 goto out; 293 } 294 295 if (val) 296 buf[0] = '1'; 297 else 298 buf[0] = '0'; 299 buf[1] = '\n'; 300 buf[2] = 0x00; 301 302 count = simple_read_from_buffer(user_buf, count, ppos, buf, 2); 303 304 out: 305 ubi_put_device(ubi); 306 return count; 307 } 308 309 /* Write an UBI debugfs file */ 310 static ssize_t dfs_file_write(struct file *file, const char __user *user_buf, 311 size_t count, loff_t *ppos) 312 { 313 unsigned long ubi_num = (unsigned long)file->private_data; 314 struct dentry *dent = file->f_path.dentry; 315 struct ubi_device *ubi; 316 struct ubi_debug_info *d; 317 size_t buf_size; 318 char buf[8] = {0}; 319 int val; 320 321 ubi = ubi_get_device(ubi_num); 322 if (!ubi) 323 return -ENODEV; 324 d = &ubi->dbg; 325 326 buf_size = min_t(size_t, count, (sizeof(buf) - 1)); 327 if (copy_from_user(buf, user_buf, buf_size)) { 328 count = -EFAULT; 329 goto out; 330 } 331 332 if (dent == d->dfs_power_cut_min) { 333 if (kstrtouint(buf, 0, &d->power_cut_min) != 0) 334 count = -EINVAL; 335 goto out; 336 } else if (dent == d->dfs_power_cut_max) { 337 if (kstrtouint(buf, 0, &d->power_cut_max) != 0) 338 count = -EINVAL; 339 goto out; 340 } else if (dent == d->dfs_emulate_power_cut) { 341 if (kstrtoint(buf, 0, &val) != 0) 342 count = -EINVAL; 343 else 344 d->emulate_power_cut = val; 345 goto out; 346 } 347 348 if (buf[0] == '1') 349 val = 1; 350 else if (buf[0] == '0') 351 val = 0; 352 else { 353 count = -EINVAL; 354 goto out; 355 } 356 357 if (dent == d->dfs_chk_gen) 358 d->chk_gen = val; 359 else if (dent == d->dfs_chk_io) 360 d->chk_io = val; 361 else if (dent == d->dfs_chk_fastmap) 362 d->chk_fastmap = val; 363 else if (dent == d->dfs_disable_bgt) 364 d->disable_bgt = val; 365 else if (dent == d->dfs_emulate_bitflips) 366 d->emulate_bitflips = val; 367 else if (dent == d->dfs_emulate_io_failures) 368 d->emulate_io_failures = val; 369 else 370 count = -EINVAL; 371 372 out: 373 ubi_put_device(ubi); 374 return count; 375 } 376 377 /* File operations for all UBI debugfs files except 378 * detailed_erase_block_info 379 */ 380 static const struct file_operations dfs_fops = { 381 .read = dfs_file_read, 382 .write = dfs_file_write, 383 .open = simple_open, 384 .llseek = no_llseek, 385 .owner = THIS_MODULE, 386 }; 387 388 /* As long as the position is less then that total number of erase blocks, 389 * we still have more to print. 390 */ 391 static void *eraseblk_count_seq_start(struct seq_file *s, loff_t *pos) 392 { 393 struct ubi_device *ubi = s->private; 394 395 if (*pos == 0) 396 return SEQ_START_TOKEN; 397 398 if (*pos < ubi->peb_count) 399 return pos; 400 401 return NULL; 402 } 403 404 /* Since we are using the position as the iterator, we just need to check if we 405 * are done and increment the position. 406 */ 407 static void *eraseblk_count_seq_next(struct seq_file *s, void *v, loff_t *pos) 408 { 409 struct ubi_device *ubi = s->private; 410 411 if (v == SEQ_START_TOKEN) 412 return pos; 413 (*pos)++; 414 415 if (*pos < ubi->peb_count) 416 return pos; 417 418 return NULL; 419 } 420 421 static void eraseblk_count_seq_stop(struct seq_file *s, void *v) 422 { 423 } 424 425 static int eraseblk_count_seq_show(struct seq_file *s, void *iter) 426 { 427 struct ubi_device *ubi = s->private; 428 struct ubi_wl_entry *wl; 429 int *block_number = iter; 430 int erase_count = -1; 431 int err; 432 433 /* If this is the start, print a header */ 434 if (iter == SEQ_START_TOKEN) { 435 seq_puts(s, 436 "physical_block_number\terase_count\tblock_status\tread_status\n"); 437 return 0; 438 } 439 440 err = ubi_io_is_bad(ubi, *block_number); 441 if (err) 442 return err; 443 444 spin_lock(&ubi->wl_lock); 445 446 wl = ubi->lookuptbl[*block_number]; 447 if (wl) 448 erase_count = wl->ec; 449 450 spin_unlock(&ubi->wl_lock); 451 452 if (erase_count < 0) 453 return 0; 454 455 seq_printf(s, "%-22d\t%-11d\n", *block_number, erase_count); 456 457 return 0; 458 } 459 460 static const struct seq_operations eraseblk_count_seq_ops = { 461 .start = eraseblk_count_seq_start, 462 .next = eraseblk_count_seq_next, 463 .stop = eraseblk_count_seq_stop, 464 .show = eraseblk_count_seq_show 465 }; 466 467 static int eraseblk_count_open(struct inode *inode, struct file *f) 468 { 469 struct seq_file *s; 470 int err; 471 472 err = seq_open(f, &eraseblk_count_seq_ops); 473 if (err) 474 return err; 475 476 s = f->private_data; 477 s->private = ubi_get_device((unsigned long)inode->i_private); 478 479 if (!s->private) 480 return -ENODEV; 481 else 482 return 0; 483 } 484 485 static int eraseblk_count_release(struct inode *inode, struct file *f) 486 { 487 struct seq_file *s = f->private_data; 488 struct ubi_device *ubi = s->private; 489 490 ubi_put_device(ubi); 491 492 return seq_release(inode, f); 493 } 494 495 static const struct file_operations eraseblk_count_fops = { 496 .owner = THIS_MODULE, 497 .open = eraseblk_count_open, 498 .read = seq_read, 499 .llseek = seq_lseek, 500 .release = eraseblk_count_release, 501 }; 502 503 /** 504 * ubi_debugfs_init_dev - initialize debugfs for an UBI device. 505 * @ubi: UBI device description object 506 * 507 * This function creates all debugfs files for UBI device @ubi. Returns zero in 508 * case of success and a negative error code in case of failure. 509 */ 510 int ubi_debugfs_init_dev(struct ubi_device *ubi) 511 { 512 int err, n; 513 unsigned long ubi_num = ubi->ubi_num; 514 const char *fname; 515 struct dentry *dent; 516 struct ubi_debug_info *d = &ubi->dbg; 517 518 if (!IS_ENABLED(CONFIG_DEBUG_FS)) 519 return 0; 520 521 n = snprintf(d->dfs_dir_name, UBI_DFS_DIR_LEN + 1, UBI_DFS_DIR_NAME, 522 ubi->ubi_num); 523 if (n == UBI_DFS_DIR_LEN) { 524 /* The array size is too small */ 525 fname = UBI_DFS_DIR_NAME; 526 dent = ERR_PTR(-EINVAL); 527 goto out; 528 } 529 530 fname = d->dfs_dir_name; 531 dent = debugfs_create_dir(fname, dfs_rootdir); 532 if (IS_ERR_OR_NULL(dent)) 533 goto out; 534 d->dfs_dir = dent; 535 536 fname = "chk_gen"; 537 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num, 538 &dfs_fops); 539 if (IS_ERR_OR_NULL(dent)) 540 goto out_remove; 541 d->dfs_chk_gen = dent; 542 543 fname = "chk_io"; 544 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num, 545 &dfs_fops); 546 if (IS_ERR_OR_NULL(dent)) 547 goto out_remove; 548 d->dfs_chk_io = dent; 549 550 fname = "chk_fastmap"; 551 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num, 552 &dfs_fops); 553 if (IS_ERR_OR_NULL(dent)) 554 goto out_remove; 555 d->dfs_chk_fastmap = dent; 556 557 fname = "tst_disable_bgt"; 558 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num, 559 &dfs_fops); 560 if (IS_ERR_OR_NULL(dent)) 561 goto out_remove; 562 d->dfs_disable_bgt = dent; 563 564 fname = "tst_emulate_bitflips"; 565 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num, 566 &dfs_fops); 567 if (IS_ERR_OR_NULL(dent)) 568 goto out_remove; 569 d->dfs_emulate_bitflips = dent; 570 571 fname = "tst_emulate_io_failures"; 572 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num, 573 &dfs_fops); 574 if (IS_ERR_OR_NULL(dent)) 575 goto out_remove; 576 d->dfs_emulate_io_failures = dent; 577 578 fname = "tst_emulate_power_cut"; 579 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num, 580 &dfs_fops); 581 if (IS_ERR_OR_NULL(dent)) 582 goto out_remove; 583 d->dfs_emulate_power_cut = dent; 584 585 fname = "tst_emulate_power_cut_min"; 586 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num, 587 &dfs_fops); 588 if (IS_ERR_OR_NULL(dent)) 589 goto out_remove; 590 d->dfs_power_cut_min = dent; 591 592 fname = "tst_emulate_power_cut_max"; 593 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num, 594 &dfs_fops); 595 if (IS_ERR_OR_NULL(dent)) 596 goto out_remove; 597 d->dfs_power_cut_max = dent; 598 599 fname = "detailed_erase_block_info"; 600 dent = debugfs_create_file(fname, S_IRUSR, d->dfs_dir, (void *)ubi_num, 601 &eraseblk_count_fops); 602 if (IS_ERR_OR_NULL(dent)) 603 goto out_remove; 604 605 return 0; 606 607 out_remove: 608 debugfs_remove_recursive(d->dfs_dir); 609 out: 610 err = dent ? PTR_ERR(dent) : -ENODEV; 611 ubi_err(ubi, "cannot create \"%s\" debugfs file or directory, error %d\n", 612 fname, err); 613 return err; 614 } 615 616 /** 617 * dbg_debug_exit_dev - free all debugfs files corresponding to device @ubi 618 * @ubi: UBI device description object 619 */ 620 void ubi_debugfs_exit_dev(struct ubi_device *ubi) 621 { 622 if (IS_ENABLED(CONFIG_DEBUG_FS)) 623 debugfs_remove_recursive(ubi->dbg.dfs_dir); 624 } 625 626 /** 627 * ubi_dbg_power_cut - emulate a power cut if it is time to do so 628 * @ubi: UBI device description object 629 * @caller: Flags set to indicate from where the function is being called 630 * 631 * Returns non-zero if a power cut was emulated, zero if not. 632 */ 633 int ubi_dbg_power_cut(struct ubi_device *ubi, int caller) 634 { 635 unsigned int range; 636 637 if ((ubi->dbg.emulate_power_cut & caller) == 0) 638 return 0; 639 640 if (ubi->dbg.power_cut_counter == 0) { 641 ubi->dbg.power_cut_counter = ubi->dbg.power_cut_min; 642 643 if (ubi->dbg.power_cut_max > ubi->dbg.power_cut_min) { 644 range = ubi->dbg.power_cut_max - ubi->dbg.power_cut_min; 645 ubi->dbg.power_cut_counter += prandom_u32() % range; 646 } 647 return 0; 648 } 649 650 ubi->dbg.power_cut_counter--; 651 if (ubi->dbg.power_cut_counter) 652 return 0; 653 654 ubi_msg(ubi, "XXXXXXXXXXXXXXX emulating a power cut XXXXXXXXXXXXXXXX"); 655 ubi_ro_mode(ubi); 656 return 1; 657 } 658