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1/*
2 * Copyright (c) International Business Machines Corp., 2006
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
12 * the GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 *
18 * Author: Artem Bityutskiy (Битюцкий Артём)
19 */
20
21#include "ubi.h"
22#include <linux/debugfs.h>
23#include <linux/uaccess.h>
24#include <linux/module.h>
25#include <linux/seq_file.h>
26
27
28/**
29 * ubi_dump_flash - dump a region of flash.
30 * @ubi: UBI device description object
31 * @pnum: the physical eraseblock number to dump
32 * @offset: the starting offset within the physical eraseblock to dump
33 * @len: the length of the region to dump
34 */
35void ubi_dump_flash(struct ubi_device *ubi, int pnum, int offset, int len)
36{
37 int err;
38 size_t read;
39 void *buf;
40 loff_t addr = (loff_t)pnum * ubi->peb_size + offset;
41
42 buf = vmalloc(len);
43 if (!buf)
44 return;
45 err = mtd_read(ubi->mtd, addr, len, &read, buf);
46 if (err && err != -EUCLEAN) {
47 ubi_err(ubi, "err %d while reading %d bytes from PEB %d:%d, read %zd bytes",
48 err, len, pnum, offset, read);
49 goto out;
50 }
51
52 ubi_msg(ubi, "dumping %d bytes of data from PEB %d, offset %d",
53 len, pnum, offset);
54 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, buf, len, 1);
55out:
56 vfree(buf);
57 return;
58}
59
60/**
61 * ubi_dump_ec_hdr - dump an erase counter header.
62 * @ec_hdr: the erase counter header to dump
63 */
64void ubi_dump_ec_hdr(const struct ubi_ec_hdr *ec_hdr)
65{
66 pr_err("Erase counter header dump:\n");
67 pr_err("\tmagic %#08x\n", be32_to_cpu(ec_hdr->magic));
68 pr_err("\tversion %d\n", (int)ec_hdr->version);
69 pr_err("\tec %llu\n", (long long)be64_to_cpu(ec_hdr->ec));
70 pr_err("\tvid_hdr_offset %d\n", be32_to_cpu(ec_hdr->vid_hdr_offset));
71 pr_err("\tdata_offset %d\n", be32_to_cpu(ec_hdr->data_offset));
72 pr_err("\timage_seq %d\n", be32_to_cpu(ec_hdr->image_seq));
73 pr_err("\thdr_crc %#08x\n", be32_to_cpu(ec_hdr->hdr_crc));
74 pr_err("erase counter header hexdump:\n");
75 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
76 ec_hdr, UBI_EC_HDR_SIZE, 1);
77}
78
79/**
80 * ubi_dump_vid_hdr - dump a volume identifier header.
81 * @vid_hdr: the volume identifier header to dump
82 */
83void ubi_dump_vid_hdr(const struct ubi_vid_hdr *vid_hdr)
84{
85 pr_err("Volume identifier header dump:\n");
86 pr_err("\tmagic %08x\n", be32_to_cpu(vid_hdr->magic));
87 pr_err("\tversion %d\n", (int)vid_hdr->version);
88 pr_err("\tvol_type %d\n", (int)vid_hdr->vol_type);
89 pr_err("\tcopy_flag %d\n", (int)vid_hdr->copy_flag);
90 pr_err("\tcompat %d\n", (int)vid_hdr->compat);
91 pr_err("\tvol_id %d\n", be32_to_cpu(vid_hdr->vol_id));
92 pr_err("\tlnum %d\n", be32_to_cpu(vid_hdr->lnum));
93 pr_err("\tdata_size %d\n", be32_to_cpu(vid_hdr->data_size));
94 pr_err("\tused_ebs %d\n", be32_to_cpu(vid_hdr->used_ebs));
95 pr_err("\tdata_pad %d\n", be32_to_cpu(vid_hdr->data_pad));
96 pr_err("\tsqnum %llu\n",
97 (unsigned long long)be64_to_cpu(vid_hdr->sqnum));
98 pr_err("\thdr_crc %08x\n", be32_to_cpu(vid_hdr->hdr_crc));
99 pr_err("Volume identifier header hexdump:\n");
100 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
101 vid_hdr, UBI_VID_HDR_SIZE, 1);
102}
103
104/**
105 * ubi_dump_vol_info - dump volume information.
106 * @vol: UBI volume description object
107 */
108void ubi_dump_vol_info(const struct ubi_volume *vol)
109{
110 pr_err("Volume information dump:\n");
111 pr_err("\tvol_id %d\n", vol->vol_id);
112 pr_err("\treserved_pebs %d\n", vol->reserved_pebs);
113 pr_err("\talignment %d\n", vol->alignment);
114 pr_err("\tdata_pad %d\n", vol->data_pad);
115 pr_err("\tvol_type %d\n", vol->vol_type);
116 pr_err("\tname_len %d\n", vol->name_len);
117 pr_err("\tusable_leb_size %d\n", vol->usable_leb_size);
118 pr_err("\tused_ebs %d\n", vol->used_ebs);
119 pr_err("\tused_bytes %lld\n", vol->used_bytes);
120 pr_err("\tlast_eb_bytes %d\n", vol->last_eb_bytes);
121 pr_err("\tcorrupted %d\n", vol->corrupted);
122 pr_err("\tupd_marker %d\n", vol->upd_marker);
123
124 if (vol->name_len <= UBI_VOL_NAME_MAX &&
125 strnlen(vol->name, vol->name_len + 1) == vol->name_len) {
126 pr_err("\tname %s\n", vol->name);
127 } else {
128 pr_err("\t1st 5 characters of name: %c%c%c%c%c\n",
129 vol->name[0], vol->name[1], vol->name[2],
130 vol->name[3], vol->name[4]);
131 }
132}
133
134/**
135 * ubi_dump_vtbl_record - dump a &struct ubi_vtbl_record object.
136 * @r: the object to dump
137 * @idx: volume table index
138 */
139void ubi_dump_vtbl_record(const struct ubi_vtbl_record *r, int idx)
140{
141 int name_len = be16_to_cpu(r->name_len);
142
143 pr_err("Volume table record %d dump:\n", idx);
144 pr_err("\treserved_pebs %d\n", be32_to_cpu(r->reserved_pebs));
145 pr_err("\talignment %d\n", be32_to_cpu(r->alignment));
146 pr_err("\tdata_pad %d\n", be32_to_cpu(r->data_pad));
147 pr_err("\tvol_type %d\n", (int)r->vol_type);
148 pr_err("\tupd_marker %d\n", (int)r->upd_marker);
149 pr_err("\tname_len %d\n", name_len);
150
151 if (r->name[0] == '\0') {
152 pr_err("\tname NULL\n");
153 return;
154 }
155
156 if (name_len <= UBI_VOL_NAME_MAX &&
157 strnlen(&r->name[0], name_len + 1) == name_len) {
158 pr_err("\tname %s\n", &r->name[0]);
159 } else {
160 pr_err("\t1st 5 characters of name: %c%c%c%c%c\n",
161 r->name[0], r->name[1], r->name[2], r->name[3],
162 r->name[4]);
163 }
164 pr_err("\tcrc %#08x\n", be32_to_cpu(r->crc));
165}
166
167/**
168 * ubi_dump_av - dump a &struct ubi_ainf_volume object.
169 * @av: the object to dump
170 */
171void ubi_dump_av(const struct ubi_ainf_volume *av)
172{
173 pr_err("Volume attaching information dump:\n");
174 pr_err("\tvol_id %d\n", av->vol_id);
175 pr_err("\thighest_lnum %d\n", av->highest_lnum);
176 pr_err("\tleb_count %d\n", av->leb_count);
177 pr_err("\tcompat %d\n", av->compat);
178 pr_err("\tvol_type %d\n", av->vol_type);
179 pr_err("\tused_ebs %d\n", av->used_ebs);
180 pr_err("\tlast_data_size %d\n", av->last_data_size);
181 pr_err("\tdata_pad %d\n", av->data_pad);
182}
183
184/**
185 * ubi_dump_aeb - dump a &struct ubi_ainf_peb object.
186 * @aeb: the object to dump
187 * @type: object type: 0 - not corrupted, 1 - corrupted
188 */
189void ubi_dump_aeb(const struct ubi_ainf_peb *aeb, int type)
190{
191 pr_err("eraseblock attaching information dump:\n");
192 pr_err("\tec %d\n", aeb->ec);
193 pr_err("\tpnum %d\n", aeb->pnum);
194 if (type == 0) {
195 pr_err("\tlnum %d\n", aeb->lnum);
196 pr_err("\tscrub %d\n", aeb->scrub);
197 pr_err("\tsqnum %llu\n", aeb->sqnum);
198 }
199}
200
201/**
202 * ubi_dump_mkvol_req - dump a &struct ubi_mkvol_req object.
203 * @req: the object to dump
204 */
205void ubi_dump_mkvol_req(const struct ubi_mkvol_req *req)
206{
207 char nm[17];
208
209 pr_err("Volume creation request dump:\n");
210 pr_err("\tvol_id %d\n", req->vol_id);
211 pr_err("\talignment %d\n", req->alignment);
212 pr_err("\tbytes %lld\n", (long long)req->bytes);
213 pr_err("\tvol_type %d\n", req->vol_type);
214 pr_err("\tname_len %d\n", req->name_len);
215
216 memcpy(nm, req->name, 16);
217 nm[16] = 0;
218 pr_err("\t1st 16 characters of name: %s\n", nm);
219}
220
221/*
222 * Root directory for UBI stuff in debugfs. Contains sub-directories which
223 * contain the stuff specific to particular UBI devices.
224 */
225static struct dentry *dfs_rootdir;
226
227/**
228 * ubi_debugfs_init - create UBI debugfs directory.
229 *
230 * Create UBI debugfs directory. Returns zero in case of success and a negative
231 * error code in case of failure.
232 */
233int ubi_debugfs_init(void)
234{
235 if (!IS_ENABLED(CONFIG_DEBUG_FS))
236 return 0;
237
238 dfs_rootdir = debugfs_create_dir("ubi", NULL);
239 if (IS_ERR_OR_NULL(dfs_rootdir)) {
240 int err = dfs_rootdir ? PTR_ERR(dfs_rootdir) : -ENODEV;
241
242 pr_err("UBI error: cannot create \"ubi\" debugfs directory, error %d\n",
243 err);
244 return err;
245 }
246
247 return 0;
248}
249
250/**
251 * ubi_debugfs_exit - remove UBI debugfs directory.
252 */
253void ubi_debugfs_exit(void)
254{
255 if (IS_ENABLED(CONFIG_DEBUG_FS))
256 debugfs_remove(dfs_rootdir);
257}
258
259/* Read an UBI debugfs file */
260static ssize_t dfs_file_read(struct file *file, char __user *user_buf,
261 size_t count, loff_t *ppos)
262{
263 unsigned long ubi_num = (unsigned long)file->private_data;
264 struct dentry *dent = file->f_path.dentry;
265 struct ubi_device *ubi;
266 struct ubi_debug_info *d;
267 char buf[8];
268 int val;
269
270 ubi = ubi_get_device(ubi_num);
271 if (!ubi)
272 return -ENODEV;
273 d = &ubi->dbg;
274
275 if (dent == d->dfs_chk_gen)
276 val = d->chk_gen;
277 else if (dent == d->dfs_chk_io)
278 val = d->chk_io;
279 else if (dent == d->dfs_chk_fastmap)
280 val = d->chk_fastmap;
281 else if (dent == d->dfs_disable_bgt)
282 val = d->disable_bgt;
283 else if (dent == d->dfs_emulate_bitflips)
284 val = d->emulate_bitflips;
285 else if (dent == d->dfs_emulate_io_failures)
286 val = d->emulate_io_failures;
287 else if (dent == d->dfs_emulate_power_cut) {
288 snprintf(buf, sizeof(buf), "%u\n", d->emulate_power_cut);
289 count = simple_read_from_buffer(user_buf, count, ppos,
290 buf, strlen(buf));
291 goto out;
292 } else if (dent == d->dfs_power_cut_min) {
293 snprintf(buf, sizeof(buf), "%u\n", d->power_cut_min);
294 count = simple_read_from_buffer(user_buf, count, ppos,
295 buf, strlen(buf));
296 goto out;
297 } else if (dent == d->dfs_power_cut_max) {
298 snprintf(buf, sizeof(buf), "%u\n", d->power_cut_max);
299 count = simple_read_from_buffer(user_buf, count, ppos,
300 buf, strlen(buf));
301 goto out;
302 }
303 else {
304 count = -EINVAL;
305 goto out;
306 }
307
308 if (val)
309 buf[0] = '1';
310 else
311 buf[0] = '0';
312 buf[1] = '\n';
313 buf[2] = 0x00;
314
315 count = simple_read_from_buffer(user_buf, count, ppos, buf, 2);
316
317out:
318 ubi_put_device(ubi);
319 return count;
320}
321
322/* Write an UBI debugfs file */
323static ssize_t dfs_file_write(struct file *file, const char __user *user_buf,
324 size_t count, loff_t *ppos)
325{
326 unsigned long ubi_num = (unsigned long)file->private_data;
327 struct dentry *dent = file->f_path.dentry;
328 struct ubi_device *ubi;
329 struct ubi_debug_info *d;
330 size_t buf_size;
331 char buf[8] = {0};
332 int val;
333
334 ubi = ubi_get_device(ubi_num);
335 if (!ubi)
336 return -ENODEV;
337 d = &ubi->dbg;
338
339 buf_size = min_t(size_t, count, (sizeof(buf) - 1));
340 if (copy_from_user(buf, user_buf, buf_size)) {
341 count = -EFAULT;
342 goto out;
343 }
344
345 if (dent == d->dfs_power_cut_min) {
346 if (kstrtouint(buf, 0, &d->power_cut_min) != 0)
347 count = -EINVAL;
348 goto out;
349 } else if (dent == d->dfs_power_cut_max) {
350 if (kstrtouint(buf, 0, &d->power_cut_max) != 0)
351 count = -EINVAL;
352 goto out;
353 } else if (dent == d->dfs_emulate_power_cut) {
354 if (kstrtoint(buf, 0, &val) != 0)
355 count = -EINVAL;
356 else
357 d->emulate_power_cut = val;
358 goto out;
359 }
360
361 if (buf[0] == '1')
362 val = 1;
363 else if (buf[0] == '0')
364 val = 0;
365 else {
366 count = -EINVAL;
367 goto out;
368 }
369
370 if (dent == d->dfs_chk_gen)
371 d->chk_gen = val;
372 else if (dent == d->dfs_chk_io)
373 d->chk_io = val;
374 else if (dent == d->dfs_chk_fastmap)
375 d->chk_fastmap = val;
376 else if (dent == d->dfs_disable_bgt)
377 d->disable_bgt = val;
378 else if (dent == d->dfs_emulate_bitflips)
379 d->emulate_bitflips = val;
380 else if (dent == d->dfs_emulate_io_failures)
381 d->emulate_io_failures = val;
382 else
383 count = -EINVAL;
384
385out:
386 ubi_put_device(ubi);
387 return count;
388}
389
390/* File operations for all UBI debugfs files except
391 * detailed_erase_block_info
392 */
393static const struct file_operations dfs_fops = {
394 .read = dfs_file_read,
395 .write = dfs_file_write,
396 .open = simple_open,
397 .llseek = no_llseek,
398 .owner = THIS_MODULE,
399};
400
401/* As long as the position is less then that total number of erase blocks,
402 * we still have more to print.
403 */
404static void *eraseblk_count_seq_start(struct seq_file *s, loff_t *pos)
405{
406 struct ubi_device *ubi = s->private;
407
408 if (*pos == 0)
409 return SEQ_START_TOKEN;
410
411 if (*pos < ubi->peb_count)
412 return pos;
413
414 return NULL;
415}
416
417/* Since we are using the position as the iterator, we just need to check if we
418 * are done and increment the position.
419 */
420static void *eraseblk_count_seq_next(struct seq_file *s, void *v, loff_t *pos)
421{
422 struct ubi_device *ubi = s->private;
423
424 if (v == SEQ_START_TOKEN)
425 return pos;
426 (*pos)++;
427
428 if (*pos < ubi->peb_count)
429 return pos;
430
431 return NULL;
432}
433
434static void eraseblk_count_seq_stop(struct seq_file *s, void *v)
435{
436}
437
438static int eraseblk_count_seq_show(struct seq_file *s, void *iter)
439{
440 struct ubi_device *ubi = s->private;
441 struct ubi_wl_entry *wl;
442 int *block_number = iter;
443 int erase_count = -1;
444 int err;
445
446 /* If this is the start, print a header */
447 if (iter == SEQ_START_TOKEN) {
448 seq_puts(s,
449 "physical_block_number\terase_count\tblock_status\tread_status\n");
450 return 0;
451 }
452
453 err = ubi_io_is_bad(ubi, *block_number);
454 if (err)
455 return err;
456
457 spin_lock(&ubi->wl_lock);
458
459 wl = ubi->lookuptbl[*block_number];
460 if (wl)
461 erase_count = wl->ec;
462
463 spin_unlock(&ubi->wl_lock);
464
465 if (erase_count < 0)
466 return 0;
467
468 seq_printf(s, "%-22d\t%-11d\n", *block_number, erase_count);
469
470 return 0;
471}
472
473static const struct seq_operations eraseblk_count_seq_ops = {
474 .start = eraseblk_count_seq_start,
475 .next = eraseblk_count_seq_next,
476 .stop = eraseblk_count_seq_stop,
477 .show = eraseblk_count_seq_show
478};
479
480static int eraseblk_count_open(struct inode *inode, struct file *f)
481{
482 struct seq_file *s;
483 int err;
484
485 err = seq_open(f, &eraseblk_count_seq_ops);
486 if (err)
487 return err;
488
489 s = f->private_data;
490 s->private = ubi_get_device((unsigned long)inode->i_private);
491
492 if (!s->private)
493 return -ENODEV;
494 else
495 return 0;
496}
497
498static int eraseblk_count_release(struct inode *inode, struct file *f)
499{
500 struct seq_file *s = f->private_data;
501 struct ubi_device *ubi = s->private;
502
503 ubi_put_device(ubi);
504
505 return seq_release(inode, f);
506}
507
508static const struct file_operations eraseblk_count_fops = {
509 .owner = THIS_MODULE,
510 .open = eraseblk_count_open,
511 .read = seq_read,
512 .llseek = seq_lseek,
513 .release = eraseblk_count_release,
514};
515
516/**
517 * ubi_debugfs_init_dev - initialize debugfs for an UBI device.
518 * @ubi: UBI device description object
519 *
520 * This function creates all debugfs files for UBI device @ubi. Returns zero in
521 * case of success and a negative error code in case of failure.
522 */
523int ubi_debugfs_init_dev(struct ubi_device *ubi)
524{
525 int err, n;
526 unsigned long ubi_num = ubi->ubi_num;
527 const char *fname;
528 struct dentry *dent;
529 struct ubi_debug_info *d = &ubi->dbg;
530
531 if (!IS_ENABLED(CONFIG_DEBUG_FS))
532 return 0;
533
534 n = snprintf(d->dfs_dir_name, UBI_DFS_DIR_LEN + 1, UBI_DFS_DIR_NAME,
535 ubi->ubi_num);
536 if (n == UBI_DFS_DIR_LEN) {
537 /* The array size is too small */
538 fname = UBI_DFS_DIR_NAME;
539 dent = ERR_PTR(-EINVAL);
540 goto out;
541 }
542
543 fname = d->dfs_dir_name;
544 dent = debugfs_create_dir(fname, dfs_rootdir);
545 if (IS_ERR_OR_NULL(dent))
546 goto out;
547 d->dfs_dir = dent;
548
549 fname = "chk_gen";
550 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
551 &dfs_fops);
552 if (IS_ERR_OR_NULL(dent))
553 goto out_remove;
554 d->dfs_chk_gen = dent;
555
556 fname = "chk_io";
557 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
558 &dfs_fops);
559 if (IS_ERR_OR_NULL(dent))
560 goto out_remove;
561 d->dfs_chk_io = dent;
562
563 fname = "chk_fastmap";
564 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
565 &dfs_fops);
566 if (IS_ERR_OR_NULL(dent))
567 goto out_remove;
568 d->dfs_chk_fastmap = dent;
569
570 fname = "tst_disable_bgt";
571 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
572 &dfs_fops);
573 if (IS_ERR_OR_NULL(dent))
574 goto out_remove;
575 d->dfs_disable_bgt = dent;
576
577 fname = "tst_emulate_bitflips";
578 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
579 &dfs_fops);
580 if (IS_ERR_OR_NULL(dent))
581 goto out_remove;
582 d->dfs_emulate_bitflips = dent;
583
584 fname = "tst_emulate_io_failures";
585 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
586 &dfs_fops);
587 if (IS_ERR_OR_NULL(dent))
588 goto out_remove;
589 d->dfs_emulate_io_failures = dent;
590
591 fname = "tst_emulate_power_cut";
592 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
593 &dfs_fops);
594 if (IS_ERR_OR_NULL(dent))
595 goto out_remove;
596 d->dfs_emulate_power_cut = dent;
597
598 fname = "tst_emulate_power_cut_min";
599 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
600 &dfs_fops);
601 if (IS_ERR_OR_NULL(dent))
602 goto out_remove;
603 d->dfs_power_cut_min = dent;
604
605 fname = "tst_emulate_power_cut_max";
606 dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
607 &dfs_fops);
608 if (IS_ERR_OR_NULL(dent))
609 goto out_remove;
610 d->dfs_power_cut_max = dent;
611
612 fname = "detailed_erase_block_info";
613 dent = debugfs_create_file(fname, S_IRUSR, d->dfs_dir, (void *)ubi_num,
614 &eraseblk_count_fops);
615 if (IS_ERR_OR_NULL(dent))
616 goto out_remove;
617
618 return 0;
619
620out_remove:
621 debugfs_remove_recursive(d->dfs_dir);
622out:
623 err = dent ? PTR_ERR(dent) : -ENODEV;
624 ubi_err(ubi, "cannot create \"%s\" debugfs file or directory, error %d\n",
625 fname, err);
626 return err;
627}
628
629/**
630 * dbg_debug_exit_dev - free all debugfs files corresponding to device @ubi
631 * @ubi: UBI device description object
632 */
633void ubi_debugfs_exit_dev(struct ubi_device *ubi)
634{
635 if (IS_ENABLED(CONFIG_DEBUG_FS))
636 debugfs_remove_recursive(ubi->dbg.dfs_dir);
637}
638
639/**
640 * ubi_dbg_power_cut - emulate a power cut if it is time to do so
641 * @ubi: UBI device description object
642 * @caller: Flags set to indicate from where the function is being called
643 *
644 * Returns non-zero if a power cut was emulated, zero if not.
645 */
646int ubi_dbg_power_cut(struct ubi_device *ubi, int caller)
647{
648 unsigned int range;
649
650 if ((ubi->dbg.emulate_power_cut & caller) == 0)
651 return 0;
652
653 if (ubi->dbg.power_cut_counter == 0) {
654 ubi->dbg.power_cut_counter = ubi->dbg.power_cut_min;
655
656 if (ubi->dbg.power_cut_max > ubi->dbg.power_cut_min) {
657 range = ubi->dbg.power_cut_max - ubi->dbg.power_cut_min;
658 ubi->dbg.power_cut_counter += prandom_u32() % range;
659 }
660 return 0;
661 }
662
663 ubi->dbg.power_cut_counter--;
664 if (ubi->dbg.power_cut_counter)
665 return 0;
666
667 ubi_msg(ubi, "XXXXXXXXXXXXXXX emulating a power cut XXXXXXXXXXXXXXXX");
668 ubi_ro_mode(ubi);
669 return 1;
670}
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 */
22void 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);
42out:
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 */
51void 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 */
70void 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 */
95void 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 */
126void 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 */
158void 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 */
176void 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 */
192void 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 */
212static 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 */
220int 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 */
240void 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 */
247static 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
304out:
305 ubi_put_device(ubi);
306 return count;
307}
308
309/* Write an UBI debugfs file */
310static 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
372out:
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 */
380static 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 */
391static 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 */
407static 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
421static void eraseblk_count_seq_stop(struct seq_file *s, void *v)
422{
423}
424
425static 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
460static 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
467static 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
485static 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
495static 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 */
510int 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
607out_remove:
608 debugfs_remove_recursive(d->dfs_dir);
609out:
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 */
620void 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 */
633int 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}