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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#include <linux/fault-inject.h>
14
15#ifdef CONFIG_MTD_UBI_FAULT_INJECTION
16static DECLARE_FAULT_ATTR(fault_eccerr_attr);
17static DECLARE_FAULT_ATTR(fault_bitflips_attr);
18static DECLARE_FAULT_ATTR(fault_read_failure_attr);
19static DECLARE_FAULT_ATTR(fault_write_failure_attr);
20static DECLARE_FAULT_ATTR(fault_erase_failure_attr);
21static DECLARE_FAULT_ATTR(fault_power_cut_attr);
22static DECLARE_FAULT_ATTR(fault_io_ff_attr);
23static DECLARE_FAULT_ATTR(fault_io_ff_bitflips_attr);
24static DECLARE_FAULT_ATTR(fault_bad_hdr_attr);
25static DECLARE_FAULT_ATTR(fault_bad_hdr_ebadmsg_attr);
26
27#define FAIL_ACTION(name, fault_attr) \
28bool should_fail_##name(void) \
29{ \
30 return should_fail(&fault_attr, 1); \
31}
32
33FAIL_ACTION(eccerr, fault_eccerr_attr)
34FAIL_ACTION(bitflips, fault_bitflips_attr)
35FAIL_ACTION(read_failure, fault_read_failure_attr)
36FAIL_ACTION(write_failure, fault_write_failure_attr)
37FAIL_ACTION(erase_failure, fault_erase_failure_attr)
38FAIL_ACTION(power_cut, fault_power_cut_attr)
39FAIL_ACTION(io_ff, fault_io_ff_attr)
40FAIL_ACTION(io_ff_bitflips, fault_io_ff_bitflips_attr)
41FAIL_ACTION(bad_hdr, fault_bad_hdr_attr)
42FAIL_ACTION(bad_hdr_ebadmsg, fault_bad_hdr_ebadmsg_attr)
43#endif
44
45/**
46 * ubi_dump_flash - dump a region of flash.
47 * @ubi: UBI device description object
48 * @pnum: the physical eraseblock number to dump
49 * @offset: the starting offset within the physical eraseblock to dump
50 * @len: the length of the region to dump
51 */
52void ubi_dump_flash(struct ubi_device *ubi, int pnum, int offset, int len)
53{
54 int err;
55 size_t read;
56 void *buf;
57 loff_t addr = (loff_t)pnum * ubi->peb_size + offset;
58
59 buf = vmalloc(len);
60 if (!buf)
61 return;
62 err = mtd_read(ubi->mtd, addr, len, &read, buf);
63 if (err && err != -EUCLEAN) {
64 ubi_err(ubi, "err %d while reading %d bytes from PEB %d:%d, read %zd bytes",
65 err, len, pnum, offset, read);
66 goto out;
67 }
68
69 ubi_msg(ubi, "dumping %d bytes of data from PEB %d, offset %d",
70 len, pnum, offset);
71 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, buf, len, 1);
72out:
73 vfree(buf);
74 return;
75}
76
77/**
78 * ubi_dump_ec_hdr - dump an erase counter header.
79 * @ec_hdr: the erase counter header to dump
80 */
81void ubi_dump_ec_hdr(const struct ubi_ec_hdr *ec_hdr)
82{
83 pr_err("Erase counter header dump:\n");
84 pr_err("\tmagic %#08x\n", be32_to_cpu(ec_hdr->magic));
85 pr_err("\tversion %d\n", (int)ec_hdr->version);
86 pr_err("\tec %llu\n", (long long)be64_to_cpu(ec_hdr->ec));
87 pr_err("\tvid_hdr_offset %d\n", be32_to_cpu(ec_hdr->vid_hdr_offset));
88 pr_err("\tdata_offset %d\n", be32_to_cpu(ec_hdr->data_offset));
89 pr_err("\timage_seq %d\n", be32_to_cpu(ec_hdr->image_seq));
90 pr_err("\thdr_crc %#08x\n", be32_to_cpu(ec_hdr->hdr_crc));
91 pr_err("erase counter header hexdump:\n");
92 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
93 ec_hdr, UBI_EC_HDR_SIZE, 1);
94}
95
96/**
97 * ubi_dump_vid_hdr - dump a volume identifier header.
98 * @vid_hdr: the volume identifier header to dump
99 */
100void ubi_dump_vid_hdr(const struct ubi_vid_hdr *vid_hdr)
101{
102 pr_err("Volume identifier header dump:\n");
103 pr_err("\tmagic %08x\n", be32_to_cpu(vid_hdr->magic));
104 pr_err("\tversion %d\n", (int)vid_hdr->version);
105 pr_err("\tvol_type %d\n", (int)vid_hdr->vol_type);
106 pr_err("\tcopy_flag %d\n", (int)vid_hdr->copy_flag);
107 pr_err("\tcompat %d\n", (int)vid_hdr->compat);
108 pr_err("\tvol_id %d\n", be32_to_cpu(vid_hdr->vol_id));
109 pr_err("\tlnum %d\n", be32_to_cpu(vid_hdr->lnum));
110 pr_err("\tdata_size %d\n", be32_to_cpu(vid_hdr->data_size));
111 pr_err("\tused_ebs %d\n", be32_to_cpu(vid_hdr->used_ebs));
112 pr_err("\tdata_pad %d\n", be32_to_cpu(vid_hdr->data_pad));
113 pr_err("\tsqnum %llu\n",
114 (unsigned long long)be64_to_cpu(vid_hdr->sqnum));
115 pr_err("\thdr_crc %08x\n", be32_to_cpu(vid_hdr->hdr_crc));
116 pr_err("Volume identifier header hexdump:\n");
117 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
118 vid_hdr, UBI_VID_HDR_SIZE, 1);
119}
120
121/**
122 * ubi_dump_vol_info - dump volume information.
123 * @vol: UBI volume description object
124 */
125void ubi_dump_vol_info(const struct ubi_volume *vol)
126{
127 pr_err("Volume information dump:\n");
128 pr_err("\tvol_id %d\n", vol->vol_id);
129 pr_err("\treserved_pebs %d\n", vol->reserved_pebs);
130 pr_err("\talignment %d\n", vol->alignment);
131 pr_err("\tdata_pad %d\n", vol->data_pad);
132 pr_err("\tvol_type %d\n", vol->vol_type);
133 pr_err("\tname_len %d\n", vol->name_len);
134 pr_err("\tusable_leb_size %d\n", vol->usable_leb_size);
135 pr_err("\tused_ebs %d\n", vol->used_ebs);
136 pr_err("\tused_bytes %lld\n", vol->used_bytes);
137 pr_err("\tlast_eb_bytes %d\n", vol->last_eb_bytes);
138 pr_err("\tcorrupted %d\n", vol->corrupted);
139 pr_err("\tupd_marker %d\n", vol->upd_marker);
140 pr_err("\tskip_check %d\n", vol->skip_check);
141
142 if (vol->name_len <= UBI_VOL_NAME_MAX &&
143 strnlen(vol->name, vol->name_len + 1) == vol->name_len) {
144 pr_err("\tname %s\n", vol->name);
145 } else {
146 pr_err("\t1st 5 characters of name: %c%c%c%c%c\n",
147 vol->name[0], vol->name[1], vol->name[2],
148 vol->name[3], vol->name[4]);
149 }
150}
151
152/**
153 * ubi_dump_vtbl_record - dump a &struct ubi_vtbl_record object.
154 * @r: the object to dump
155 * @idx: volume table index
156 */
157void ubi_dump_vtbl_record(const struct ubi_vtbl_record *r, int idx)
158{
159 int name_len = be16_to_cpu(r->name_len);
160
161 pr_err("Volume table record %d dump:\n", idx);
162 pr_err("\treserved_pebs %d\n", be32_to_cpu(r->reserved_pebs));
163 pr_err("\talignment %d\n", be32_to_cpu(r->alignment));
164 pr_err("\tdata_pad %d\n", be32_to_cpu(r->data_pad));
165 pr_err("\tvol_type %d\n", (int)r->vol_type);
166 pr_err("\tupd_marker %d\n", (int)r->upd_marker);
167 pr_err("\tname_len %d\n", name_len);
168
169 if (r->name[0] == '\0') {
170 pr_err("\tname NULL\n");
171 return;
172 }
173
174 if (name_len <= UBI_VOL_NAME_MAX &&
175 strnlen(&r->name[0], name_len + 1) == name_len) {
176 pr_err("\tname %s\n", &r->name[0]);
177 } else {
178 pr_err("\t1st 5 characters of name: %c%c%c%c%c\n",
179 r->name[0], r->name[1], r->name[2], r->name[3],
180 r->name[4]);
181 }
182 pr_err("\tcrc %#08x\n", be32_to_cpu(r->crc));
183}
184
185/**
186 * ubi_dump_av - dump a &struct ubi_ainf_volume object.
187 * @av: the object to dump
188 */
189void ubi_dump_av(const struct ubi_ainf_volume *av)
190{
191 pr_err("Volume attaching information dump:\n");
192 pr_err("\tvol_id %d\n", av->vol_id);
193 pr_err("\thighest_lnum %d\n", av->highest_lnum);
194 pr_err("\tleb_count %d\n", av->leb_count);
195 pr_err("\tcompat %d\n", av->compat);
196 pr_err("\tvol_type %d\n", av->vol_type);
197 pr_err("\tused_ebs %d\n", av->used_ebs);
198 pr_err("\tlast_data_size %d\n", av->last_data_size);
199 pr_err("\tdata_pad %d\n", av->data_pad);
200}
201
202/**
203 * ubi_dump_aeb - dump a &struct ubi_ainf_peb object.
204 * @aeb: the object to dump
205 * @type: object type: 0 - not corrupted, 1 - corrupted
206 */
207void ubi_dump_aeb(const struct ubi_ainf_peb *aeb, int type)
208{
209 pr_err("eraseblock attaching information dump:\n");
210 pr_err("\tec %d\n", aeb->ec);
211 pr_err("\tpnum %d\n", aeb->pnum);
212 if (type == 0) {
213 pr_err("\tlnum %d\n", aeb->lnum);
214 pr_err("\tscrub %d\n", aeb->scrub);
215 pr_err("\tsqnum %llu\n", aeb->sqnum);
216 }
217}
218
219/**
220 * ubi_dump_mkvol_req - dump a &struct ubi_mkvol_req object.
221 * @req: the object to dump
222 */
223void ubi_dump_mkvol_req(const struct ubi_mkvol_req *req)
224{
225 char nm[17];
226
227 pr_err("Volume creation request dump:\n");
228 pr_err("\tvol_id %d\n", req->vol_id);
229 pr_err("\talignment %d\n", req->alignment);
230 pr_err("\tbytes %lld\n", (long long)req->bytes);
231 pr_err("\tvol_type %d\n", req->vol_type);
232 pr_err("\tname_len %d\n", req->name_len);
233
234 memcpy(nm, req->name, 16);
235 nm[16] = 0;
236 pr_err("\t1st 16 characters of name: %s\n", nm);
237}
238
239/*
240 * Root directory for UBI stuff in debugfs. Contains sub-directories which
241 * contain the stuff specific to particular UBI devices.
242 */
243static struct dentry *dfs_rootdir;
244
245#ifdef CONFIG_MTD_UBI_FAULT_INJECTION
246static void dfs_create_fault_entry(struct dentry *parent)
247{
248 struct dentry *dir;
249
250 dir = debugfs_create_dir("fault_inject", parent);
251 if (IS_ERR_OR_NULL(dir)) {
252 int err = dir ? PTR_ERR(dir) : -ENODEV;
253
254 pr_warn("UBI error: cannot create \"fault_inject\" debugfs directory, error %d\n",
255 err);
256 return;
257 }
258
259 fault_create_debugfs_attr("emulate_eccerr", dir,
260 &fault_eccerr_attr);
261
262 fault_create_debugfs_attr("emulate_read_failure", dir,
263 &fault_read_failure_attr);
264
265 fault_create_debugfs_attr("emulate_bitflips", dir,
266 &fault_bitflips_attr);
267
268 fault_create_debugfs_attr("emulate_write_failure", dir,
269 &fault_write_failure_attr);
270
271 fault_create_debugfs_attr("emulate_erase_failure", dir,
272 &fault_erase_failure_attr);
273
274 fault_create_debugfs_attr("emulate_power_cut", dir,
275 &fault_power_cut_attr);
276
277 fault_create_debugfs_attr("emulate_io_ff", dir,
278 &fault_io_ff_attr);
279
280 fault_create_debugfs_attr("emulate_io_ff_bitflips", dir,
281 &fault_io_ff_bitflips_attr);
282
283 fault_create_debugfs_attr("emulate_bad_hdr", dir,
284 &fault_bad_hdr_attr);
285
286 fault_create_debugfs_attr("emulate_bad_hdr_ebadmsg", dir,
287 &fault_bad_hdr_ebadmsg_attr);
288}
289#endif
290
291/**
292 * ubi_debugfs_init - create UBI debugfs directory.
293 *
294 * Create UBI debugfs directory. Returns zero in case of success and a negative
295 * error code in case of failure.
296 */
297int ubi_debugfs_init(void)
298{
299 if (!IS_ENABLED(CONFIG_DEBUG_FS))
300 return 0;
301
302 dfs_rootdir = debugfs_create_dir("ubi", NULL);
303 if (IS_ERR_OR_NULL(dfs_rootdir)) {
304 int err = dfs_rootdir ? PTR_ERR(dfs_rootdir) : -ENODEV;
305
306 pr_err("UBI error: cannot create \"ubi\" debugfs directory, error %d\n",
307 err);
308 return err;
309 }
310
311#ifdef CONFIG_MTD_UBI_FAULT_INJECTION
312 dfs_create_fault_entry(dfs_rootdir);
313#endif
314
315 return 0;
316}
317
318/**
319 * ubi_debugfs_exit - remove UBI debugfs directory.
320 */
321void ubi_debugfs_exit(void)
322{
323 if (IS_ENABLED(CONFIG_DEBUG_FS))
324 debugfs_remove(dfs_rootdir);
325}
326
327/* Read an UBI debugfs file */
328static ssize_t dfs_file_read(struct file *file, char __user *user_buf,
329 size_t count, loff_t *ppos)
330{
331 unsigned long ubi_num = (unsigned long)file->private_data;
332 struct dentry *dent = file->f_path.dentry;
333 struct ubi_device *ubi;
334 struct ubi_debug_info *d;
335 char buf[16];
336 int val;
337
338 ubi = ubi_get_device(ubi_num);
339 if (!ubi)
340 return -ENODEV;
341 d = &ubi->dbg;
342
343 if (dent == d->dfs_chk_gen)
344 val = d->chk_gen;
345 else if (dent == d->dfs_chk_io)
346 val = d->chk_io;
347 else if (dent == d->dfs_chk_fastmap)
348 val = d->chk_fastmap;
349 else if (dent == d->dfs_disable_bgt)
350 val = d->disable_bgt;
351 else if (dent == d->dfs_emulate_bitflips)
352 val = d->emulate_bitflips;
353 else if (dent == d->dfs_emulate_io_failures)
354 val = d->emulate_io_failures;
355 else if (dent == d->dfs_emulate_failures) {
356 snprintf(buf, sizeof(buf), "0x%04x\n", d->emulate_failures);
357 count = simple_read_from_buffer(user_buf, count, ppos,
358 buf, strlen(buf));
359 goto out;
360 } else if (dent == d->dfs_emulate_power_cut) {
361 snprintf(buf, sizeof(buf), "%u\n", d->emulate_power_cut);
362 count = simple_read_from_buffer(user_buf, count, ppos,
363 buf, strlen(buf));
364 goto out;
365 } else if (dent == d->dfs_power_cut_min) {
366 snprintf(buf, sizeof(buf), "%u\n", d->power_cut_min);
367 count = simple_read_from_buffer(user_buf, count, ppos,
368 buf, strlen(buf));
369 goto out;
370 } else if (dent == d->dfs_power_cut_max) {
371 snprintf(buf, sizeof(buf), "%u\n", d->power_cut_max);
372 count = simple_read_from_buffer(user_buf, count, ppos,
373 buf, strlen(buf));
374 goto out;
375 } else {
376 count = -EINVAL;
377 goto out;
378 }
379
380 if (val)
381 buf[0] = '1';
382 else
383 buf[0] = '0';
384 buf[1] = '\n';
385 buf[2] = 0x00;
386
387 count = simple_read_from_buffer(user_buf, count, ppos, buf, 2);
388
389out:
390 ubi_put_device(ubi);
391 return count;
392}
393
394/* Write an UBI debugfs file */
395static ssize_t dfs_file_write(struct file *file, const char __user *user_buf,
396 size_t count, loff_t *ppos)
397{
398 unsigned long ubi_num = (unsigned long)file->private_data;
399 struct dentry *dent = file->f_path.dentry;
400 struct ubi_device *ubi;
401 struct ubi_debug_info *d;
402 size_t buf_size;
403 char buf[16] = {0};
404 int val;
405
406 ubi = ubi_get_device(ubi_num);
407 if (!ubi)
408 return -ENODEV;
409 d = &ubi->dbg;
410
411 buf_size = min_t(size_t, count, (sizeof(buf) - 1));
412 if (copy_from_user(buf, user_buf, buf_size)) {
413 count = -EFAULT;
414 goto out;
415 }
416
417 if (dent == d->dfs_emulate_failures) {
418 if (kstrtouint(buf, 0, &d->emulate_failures) != 0)
419 count = -EINVAL;
420 goto out;
421 } else if (dent == d->dfs_power_cut_min) {
422 if (kstrtouint(buf, 0, &d->power_cut_min) != 0)
423 count = -EINVAL;
424 goto out;
425 } else if (dent == d->dfs_power_cut_max) {
426 if (kstrtouint(buf, 0, &d->power_cut_max) != 0)
427 count = -EINVAL;
428 goto out;
429 } else if (dent == d->dfs_emulate_power_cut) {
430 if (kstrtoint(buf, 0, &val) != 0)
431 count = -EINVAL;
432 else
433 d->emulate_power_cut = val;
434 goto out;
435 }
436
437 if (buf[0] == '1')
438 val = 1;
439 else if (buf[0] == '0')
440 val = 0;
441 else {
442 count = -EINVAL;
443 goto out;
444 }
445
446 if (dent == d->dfs_chk_gen)
447 d->chk_gen = val;
448 else if (dent == d->dfs_chk_io)
449 d->chk_io = val;
450 else if (dent == d->dfs_chk_fastmap)
451 d->chk_fastmap = val;
452 else if (dent == d->dfs_disable_bgt)
453 d->disable_bgt = val;
454 else if (dent == d->dfs_emulate_bitflips)
455 d->emulate_bitflips = val;
456 else if (dent == d->dfs_emulate_io_failures)
457 d->emulate_io_failures = val;
458 else
459 count = -EINVAL;
460
461out:
462 ubi_put_device(ubi);
463 return count;
464}
465
466/* File operations for all UBI debugfs files except
467 * detailed_erase_block_info
468 */
469static const struct file_operations dfs_fops = {
470 .read = dfs_file_read,
471 .write = dfs_file_write,
472 .open = simple_open,
473 .llseek = no_llseek,
474 .owner = THIS_MODULE,
475};
476
477/* As long as the position is less then that total number of erase blocks,
478 * we still have more to print.
479 */
480static void *eraseblk_count_seq_start(struct seq_file *s, loff_t *pos)
481{
482 struct ubi_device *ubi = s->private;
483
484 if (*pos < ubi->peb_count)
485 return pos;
486
487 return NULL;
488}
489
490/* Since we are using the position as the iterator, we just need to check if we
491 * are done and increment the position.
492 */
493static void *eraseblk_count_seq_next(struct seq_file *s, void *v, loff_t *pos)
494{
495 struct ubi_device *ubi = s->private;
496
497 (*pos)++;
498
499 if (*pos < ubi->peb_count)
500 return pos;
501
502 return NULL;
503}
504
505static void eraseblk_count_seq_stop(struct seq_file *s, void *v)
506{
507}
508
509static int eraseblk_count_seq_show(struct seq_file *s, void *iter)
510{
511 struct ubi_device *ubi = s->private;
512 struct ubi_wl_entry *wl;
513 int *block_number = iter;
514 int erase_count = -1;
515 int err;
516
517 /* If this is the start, print a header */
518 if (*block_number == 0)
519 seq_puts(s, "physical_block_number\terase_count\n");
520
521 err = ubi_io_is_bad(ubi, *block_number);
522 if (err)
523 return err;
524
525 spin_lock(&ubi->wl_lock);
526
527 wl = ubi->lookuptbl[*block_number];
528 if (wl)
529 erase_count = wl->ec;
530
531 spin_unlock(&ubi->wl_lock);
532
533 if (erase_count < 0)
534 return 0;
535
536 seq_printf(s, "%-22d\t%-11d\n", *block_number, erase_count);
537
538 return 0;
539}
540
541static const struct seq_operations eraseblk_count_seq_ops = {
542 .start = eraseblk_count_seq_start,
543 .next = eraseblk_count_seq_next,
544 .stop = eraseblk_count_seq_stop,
545 .show = eraseblk_count_seq_show
546};
547
548static int eraseblk_count_open(struct inode *inode, struct file *f)
549{
550 struct seq_file *s;
551 int err;
552
553 err = seq_open(f, &eraseblk_count_seq_ops);
554 if (err)
555 return err;
556
557 s = f->private_data;
558 s->private = ubi_get_device((unsigned long)inode->i_private);
559
560 if (!s->private)
561 return -ENODEV;
562 else
563 return 0;
564}
565
566static int eraseblk_count_release(struct inode *inode, struct file *f)
567{
568 struct seq_file *s = f->private_data;
569 struct ubi_device *ubi = s->private;
570
571 ubi_put_device(ubi);
572
573 return seq_release(inode, f);
574}
575
576static const struct file_operations eraseblk_count_fops = {
577 .owner = THIS_MODULE,
578 .open = eraseblk_count_open,
579 .read = seq_read,
580 .llseek = seq_lseek,
581 .release = eraseblk_count_release,
582};
583
584/**
585 * ubi_debugfs_init_dev - initialize debugfs for an UBI device.
586 * @ubi: UBI device description object
587 *
588 * This function creates all debugfs files for UBI device @ubi. Returns zero in
589 * case of success and a negative error code in case of failure.
590 */
591int ubi_debugfs_init_dev(struct ubi_device *ubi)
592{
593 unsigned long ubi_num = ubi->ubi_num;
594 struct ubi_debug_info *d = &ubi->dbg;
595 umode_t mode = S_IRUSR | S_IWUSR;
596 int n;
597
598 if (!IS_ENABLED(CONFIG_DEBUG_FS))
599 return 0;
600
601 n = snprintf(d->dfs_dir_name, UBI_DFS_DIR_LEN + 1, UBI_DFS_DIR_NAME,
602 ubi->ubi_num);
603 if (n > UBI_DFS_DIR_LEN) {
604 /* The array size is too small */
605 return -EINVAL;
606 }
607
608 d->dfs_dir = debugfs_create_dir(d->dfs_dir_name, dfs_rootdir);
609
610 d->dfs_chk_gen = debugfs_create_file("chk_gen", mode, d->dfs_dir,
611 (void *)ubi_num, &dfs_fops);
612
613 d->dfs_chk_io = debugfs_create_file("chk_io", mode, d->dfs_dir,
614 (void *)ubi_num, &dfs_fops);
615
616 d->dfs_chk_fastmap = debugfs_create_file("chk_fastmap", mode,
617 d->dfs_dir, (void *)ubi_num,
618 &dfs_fops);
619
620 d->dfs_disable_bgt = debugfs_create_file("tst_disable_bgt", mode,
621 d->dfs_dir, (void *)ubi_num,
622 &dfs_fops);
623
624 d->dfs_emulate_bitflips = debugfs_create_file("tst_emulate_bitflips",
625 mode, d->dfs_dir,
626 (void *)ubi_num,
627 &dfs_fops);
628
629 d->dfs_emulate_io_failures = debugfs_create_file("tst_emulate_io_failures",
630 mode, d->dfs_dir,
631 (void *)ubi_num,
632 &dfs_fops);
633
634 d->dfs_emulate_power_cut = debugfs_create_file("tst_emulate_power_cut",
635 mode, d->dfs_dir,
636 (void *)ubi_num,
637 &dfs_fops);
638
639 d->dfs_power_cut_min = debugfs_create_file("tst_emulate_power_cut_min",
640 mode, d->dfs_dir,
641 (void *)ubi_num, &dfs_fops);
642
643 d->dfs_power_cut_max = debugfs_create_file("tst_emulate_power_cut_max",
644 mode, d->dfs_dir,
645 (void *)ubi_num, &dfs_fops);
646
647 debugfs_create_file("detailed_erase_block_info", S_IRUSR, d->dfs_dir,
648 (void *)ubi_num, &eraseblk_count_fops);
649
650#ifdef CONFIG_MTD_UBI_FAULT_INJECTION
651 d->dfs_emulate_failures = debugfs_create_file("emulate_failures",
652 mode, d->dfs_dir,
653 (void *)ubi_num,
654 &dfs_fops);
655#endif
656 return 0;
657}
658
659/**
660 * ubi_debugfs_exit_dev - free all debugfs files corresponding to device @ubi
661 * @ubi: UBI device description object
662 */
663void ubi_debugfs_exit_dev(struct ubi_device *ubi)
664{
665 if (IS_ENABLED(CONFIG_DEBUG_FS))
666 debugfs_remove_recursive(ubi->dbg.dfs_dir);
667}
668
669/**
670 * ubi_dbg_power_cut - emulate a power cut if it is time to do so
671 * @ubi: UBI device description object
672 * @caller: Flags set to indicate from where the function is being called
673 *
674 * Returns non-zero if a power cut was emulated, zero if not.
675 */
676int ubi_dbg_power_cut(struct ubi_device *ubi, int caller)
677{
678 unsigned int range;
679
680 if ((ubi->dbg.emulate_power_cut & caller) == 0)
681 return 0;
682
683 if (ubi->dbg.power_cut_counter == 0) {
684 ubi->dbg.power_cut_counter = ubi->dbg.power_cut_min;
685
686 if (ubi->dbg.power_cut_max > ubi->dbg.power_cut_min) {
687 range = ubi->dbg.power_cut_max - ubi->dbg.power_cut_min;
688 ubi->dbg.power_cut_counter += get_random_u32_below(range);
689 }
690 return 0;
691 }
692
693 ubi->dbg.power_cut_counter--;
694 if (ubi->dbg.power_cut_counter)
695 return 0;
696
697 return 1;
698}
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 pr_err("\tskip_check %d\n", vol->skip_check);
111
112 if (vol->name_len <= UBI_VOL_NAME_MAX &&
113 strnlen(vol->name, vol->name_len + 1) == vol->name_len) {
114 pr_err("\tname %s\n", vol->name);
115 } else {
116 pr_err("\t1st 5 characters of name: %c%c%c%c%c\n",
117 vol->name[0], vol->name[1], vol->name[2],
118 vol->name[3], vol->name[4]);
119 }
120}
121
122/**
123 * ubi_dump_vtbl_record - dump a &struct ubi_vtbl_record object.
124 * @r: the object to dump
125 * @idx: volume table index
126 */
127void ubi_dump_vtbl_record(const struct ubi_vtbl_record *r, int idx)
128{
129 int name_len = be16_to_cpu(r->name_len);
130
131 pr_err("Volume table record %d dump:\n", idx);
132 pr_err("\treserved_pebs %d\n", be32_to_cpu(r->reserved_pebs));
133 pr_err("\talignment %d\n", be32_to_cpu(r->alignment));
134 pr_err("\tdata_pad %d\n", be32_to_cpu(r->data_pad));
135 pr_err("\tvol_type %d\n", (int)r->vol_type);
136 pr_err("\tupd_marker %d\n", (int)r->upd_marker);
137 pr_err("\tname_len %d\n", name_len);
138
139 if (r->name[0] == '\0') {
140 pr_err("\tname NULL\n");
141 return;
142 }
143
144 if (name_len <= UBI_VOL_NAME_MAX &&
145 strnlen(&r->name[0], name_len + 1) == name_len) {
146 pr_err("\tname %s\n", &r->name[0]);
147 } else {
148 pr_err("\t1st 5 characters of name: %c%c%c%c%c\n",
149 r->name[0], r->name[1], r->name[2], r->name[3],
150 r->name[4]);
151 }
152 pr_err("\tcrc %#08x\n", be32_to_cpu(r->crc));
153}
154
155/**
156 * ubi_dump_av - dump a &struct ubi_ainf_volume object.
157 * @av: the object to dump
158 */
159void ubi_dump_av(const struct ubi_ainf_volume *av)
160{
161 pr_err("Volume attaching information dump:\n");
162 pr_err("\tvol_id %d\n", av->vol_id);
163 pr_err("\thighest_lnum %d\n", av->highest_lnum);
164 pr_err("\tleb_count %d\n", av->leb_count);
165 pr_err("\tcompat %d\n", av->compat);
166 pr_err("\tvol_type %d\n", av->vol_type);
167 pr_err("\tused_ebs %d\n", av->used_ebs);
168 pr_err("\tlast_data_size %d\n", av->last_data_size);
169 pr_err("\tdata_pad %d\n", av->data_pad);
170}
171
172/**
173 * ubi_dump_aeb - dump a &struct ubi_ainf_peb object.
174 * @aeb: the object to dump
175 * @type: object type: 0 - not corrupted, 1 - corrupted
176 */
177void ubi_dump_aeb(const struct ubi_ainf_peb *aeb, int type)
178{
179 pr_err("eraseblock attaching information dump:\n");
180 pr_err("\tec %d\n", aeb->ec);
181 pr_err("\tpnum %d\n", aeb->pnum);
182 if (type == 0) {
183 pr_err("\tlnum %d\n", aeb->lnum);
184 pr_err("\tscrub %d\n", aeb->scrub);
185 pr_err("\tsqnum %llu\n", aeb->sqnum);
186 }
187}
188
189/**
190 * ubi_dump_mkvol_req - dump a &struct ubi_mkvol_req object.
191 * @req: the object to dump
192 */
193void ubi_dump_mkvol_req(const struct ubi_mkvol_req *req)
194{
195 char nm[17];
196
197 pr_err("Volume creation request dump:\n");
198 pr_err("\tvol_id %d\n", req->vol_id);
199 pr_err("\talignment %d\n", req->alignment);
200 pr_err("\tbytes %lld\n", (long long)req->bytes);
201 pr_err("\tvol_type %d\n", req->vol_type);
202 pr_err("\tname_len %d\n", req->name_len);
203
204 memcpy(nm, req->name, 16);
205 nm[16] = 0;
206 pr_err("\t1st 16 characters of name: %s\n", nm);
207}
208
209/*
210 * Root directory for UBI stuff in debugfs. Contains sub-directories which
211 * contain the stuff specific to particular UBI devices.
212 */
213static struct dentry *dfs_rootdir;
214
215/**
216 * ubi_debugfs_init - create UBI debugfs directory.
217 *
218 * Create UBI debugfs directory. Returns zero in case of success and a negative
219 * error code in case of failure.
220 */
221int ubi_debugfs_init(void)
222{
223 if (!IS_ENABLED(CONFIG_DEBUG_FS))
224 return 0;
225
226 dfs_rootdir = debugfs_create_dir("ubi", NULL);
227 if (IS_ERR_OR_NULL(dfs_rootdir)) {
228 int err = dfs_rootdir ? PTR_ERR(dfs_rootdir) : -ENODEV;
229
230 pr_err("UBI error: cannot create \"ubi\" debugfs directory, error %d\n",
231 err);
232 return err;
233 }
234
235 return 0;
236}
237
238/**
239 * ubi_debugfs_exit - remove UBI debugfs directory.
240 */
241void ubi_debugfs_exit(void)
242{
243 if (IS_ENABLED(CONFIG_DEBUG_FS))
244 debugfs_remove(dfs_rootdir);
245}
246
247/* Read an UBI debugfs file */
248static ssize_t dfs_file_read(struct file *file, char __user *user_buf,
249 size_t count, loff_t *ppos)
250{
251 unsigned long ubi_num = (unsigned long)file->private_data;
252 struct dentry *dent = file->f_path.dentry;
253 struct ubi_device *ubi;
254 struct ubi_debug_info *d;
255 char buf[8];
256 int val;
257
258 ubi = ubi_get_device(ubi_num);
259 if (!ubi)
260 return -ENODEV;
261 d = &ubi->dbg;
262
263 if (dent == d->dfs_chk_gen)
264 val = d->chk_gen;
265 else if (dent == d->dfs_chk_io)
266 val = d->chk_io;
267 else if (dent == d->dfs_chk_fastmap)
268 val = d->chk_fastmap;
269 else if (dent == d->dfs_disable_bgt)
270 val = d->disable_bgt;
271 else if (dent == d->dfs_emulate_bitflips)
272 val = d->emulate_bitflips;
273 else if (dent == d->dfs_emulate_io_failures)
274 val = d->emulate_io_failures;
275 else if (dent == d->dfs_emulate_power_cut) {
276 snprintf(buf, sizeof(buf), "%u\n", d->emulate_power_cut);
277 count = simple_read_from_buffer(user_buf, count, ppos,
278 buf, strlen(buf));
279 goto out;
280 } else if (dent == d->dfs_power_cut_min) {
281 snprintf(buf, sizeof(buf), "%u\n", d->power_cut_min);
282 count = simple_read_from_buffer(user_buf, count, ppos,
283 buf, strlen(buf));
284 goto out;
285 } else if (dent == d->dfs_power_cut_max) {
286 snprintf(buf, sizeof(buf), "%u\n", d->power_cut_max);
287 count = simple_read_from_buffer(user_buf, count, ppos,
288 buf, strlen(buf));
289 goto out;
290 }
291 else {
292 count = -EINVAL;
293 goto out;
294 }
295
296 if (val)
297 buf[0] = '1';
298 else
299 buf[0] = '0';
300 buf[1] = '\n';
301 buf[2] = 0x00;
302
303 count = simple_read_from_buffer(user_buf, count, ppos, buf, 2);
304
305out:
306 ubi_put_device(ubi);
307 return count;
308}
309
310/* Write an UBI debugfs file */
311static ssize_t dfs_file_write(struct file *file, const char __user *user_buf,
312 size_t count, loff_t *ppos)
313{
314 unsigned long ubi_num = (unsigned long)file->private_data;
315 struct dentry *dent = file->f_path.dentry;
316 struct ubi_device *ubi;
317 struct ubi_debug_info *d;
318 size_t buf_size;
319 char buf[8] = {0};
320 int val;
321
322 ubi = ubi_get_device(ubi_num);
323 if (!ubi)
324 return -ENODEV;
325 d = &ubi->dbg;
326
327 buf_size = min_t(size_t, count, (sizeof(buf) - 1));
328 if (copy_from_user(buf, user_buf, buf_size)) {
329 count = -EFAULT;
330 goto out;
331 }
332
333 if (dent == d->dfs_power_cut_min) {
334 if (kstrtouint(buf, 0, &d->power_cut_min) != 0)
335 count = -EINVAL;
336 goto out;
337 } else if (dent == d->dfs_power_cut_max) {
338 if (kstrtouint(buf, 0, &d->power_cut_max) != 0)
339 count = -EINVAL;
340 goto out;
341 } else if (dent == d->dfs_emulate_power_cut) {
342 if (kstrtoint(buf, 0, &val) != 0)
343 count = -EINVAL;
344 else
345 d->emulate_power_cut = val;
346 goto out;
347 }
348
349 if (buf[0] == '1')
350 val = 1;
351 else if (buf[0] == '0')
352 val = 0;
353 else {
354 count = -EINVAL;
355 goto out;
356 }
357
358 if (dent == d->dfs_chk_gen)
359 d->chk_gen = val;
360 else if (dent == d->dfs_chk_io)
361 d->chk_io = val;
362 else if (dent == d->dfs_chk_fastmap)
363 d->chk_fastmap = val;
364 else if (dent == d->dfs_disable_bgt)
365 d->disable_bgt = val;
366 else if (dent == d->dfs_emulate_bitflips)
367 d->emulate_bitflips = val;
368 else if (dent == d->dfs_emulate_io_failures)
369 d->emulate_io_failures = val;
370 else
371 count = -EINVAL;
372
373out:
374 ubi_put_device(ubi);
375 return count;
376}
377
378/* File operations for all UBI debugfs files except
379 * detailed_erase_block_info
380 */
381static const struct file_operations dfs_fops = {
382 .read = dfs_file_read,
383 .write = dfs_file_write,
384 .open = simple_open,
385 .llseek = no_llseek,
386 .owner = THIS_MODULE,
387};
388
389/* As long as the position is less then that total number of erase blocks,
390 * we still have more to print.
391 */
392static void *eraseblk_count_seq_start(struct seq_file *s, loff_t *pos)
393{
394 struct ubi_device *ubi = s->private;
395
396 if (*pos < ubi->peb_count)
397 return pos;
398
399 return NULL;
400}
401
402/* Since we are using the position as the iterator, we just need to check if we
403 * are done and increment the position.
404 */
405static void *eraseblk_count_seq_next(struct seq_file *s, void *v, loff_t *pos)
406{
407 struct ubi_device *ubi = s->private;
408
409 (*pos)++;
410
411 if (*pos < ubi->peb_count)
412 return pos;
413
414 return NULL;
415}
416
417static void eraseblk_count_seq_stop(struct seq_file *s, void *v)
418{
419}
420
421static int eraseblk_count_seq_show(struct seq_file *s, void *iter)
422{
423 struct ubi_device *ubi = s->private;
424 struct ubi_wl_entry *wl;
425 int *block_number = iter;
426 int erase_count = -1;
427 int err;
428
429 /* If this is the start, print a header */
430 if (*block_number == 0)
431 seq_puts(s, "physical_block_number\terase_count\n");
432
433 err = ubi_io_is_bad(ubi, *block_number);
434 if (err)
435 return err;
436
437 spin_lock(&ubi->wl_lock);
438
439 wl = ubi->lookuptbl[*block_number];
440 if (wl)
441 erase_count = wl->ec;
442
443 spin_unlock(&ubi->wl_lock);
444
445 if (erase_count < 0)
446 return 0;
447
448 seq_printf(s, "%-22d\t%-11d\n", *block_number, erase_count);
449
450 return 0;
451}
452
453static const struct seq_operations eraseblk_count_seq_ops = {
454 .start = eraseblk_count_seq_start,
455 .next = eraseblk_count_seq_next,
456 .stop = eraseblk_count_seq_stop,
457 .show = eraseblk_count_seq_show
458};
459
460static int eraseblk_count_open(struct inode *inode, struct file *f)
461{
462 struct seq_file *s;
463 int err;
464
465 err = seq_open(f, &eraseblk_count_seq_ops);
466 if (err)
467 return err;
468
469 s = f->private_data;
470 s->private = ubi_get_device((unsigned long)inode->i_private);
471
472 if (!s->private)
473 return -ENODEV;
474 else
475 return 0;
476}
477
478static int eraseblk_count_release(struct inode *inode, struct file *f)
479{
480 struct seq_file *s = f->private_data;
481 struct ubi_device *ubi = s->private;
482
483 ubi_put_device(ubi);
484
485 return seq_release(inode, f);
486}
487
488static const struct file_operations eraseblk_count_fops = {
489 .owner = THIS_MODULE,
490 .open = eraseblk_count_open,
491 .read = seq_read,
492 .llseek = seq_lseek,
493 .release = eraseblk_count_release,
494};
495
496/**
497 * ubi_debugfs_init_dev - initialize debugfs for an UBI device.
498 * @ubi: UBI device description object
499 *
500 * This function creates all debugfs files for UBI device @ubi. Returns zero in
501 * case of success and a negative error code in case of failure.
502 */
503int ubi_debugfs_init_dev(struct ubi_device *ubi)
504{
505 unsigned long ubi_num = ubi->ubi_num;
506 struct ubi_debug_info *d = &ubi->dbg;
507 int n;
508
509 if (!IS_ENABLED(CONFIG_DEBUG_FS))
510 return 0;
511
512 n = snprintf(d->dfs_dir_name, UBI_DFS_DIR_LEN + 1, UBI_DFS_DIR_NAME,
513 ubi->ubi_num);
514 if (n == UBI_DFS_DIR_LEN) {
515 /* The array size is too small */
516 return -EINVAL;
517 }
518
519 d->dfs_dir = debugfs_create_dir(d->dfs_dir_name, dfs_rootdir);
520
521 d->dfs_chk_gen = debugfs_create_file("chk_gen", S_IWUSR, d->dfs_dir,
522 (void *)ubi_num, &dfs_fops);
523
524 d->dfs_chk_io = debugfs_create_file("chk_io", S_IWUSR, d->dfs_dir,
525 (void *)ubi_num, &dfs_fops);
526
527 d->dfs_chk_fastmap = debugfs_create_file("chk_fastmap", S_IWUSR,
528 d->dfs_dir, (void *)ubi_num,
529 &dfs_fops);
530
531 d->dfs_disable_bgt = debugfs_create_file("tst_disable_bgt", S_IWUSR,
532 d->dfs_dir, (void *)ubi_num,
533 &dfs_fops);
534
535 d->dfs_emulate_bitflips = debugfs_create_file("tst_emulate_bitflips",
536 S_IWUSR, d->dfs_dir,
537 (void *)ubi_num,
538 &dfs_fops);
539
540 d->dfs_emulate_io_failures = debugfs_create_file("tst_emulate_io_failures",
541 S_IWUSR, d->dfs_dir,
542 (void *)ubi_num,
543 &dfs_fops);
544
545 d->dfs_emulate_power_cut = debugfs_create_file("tst_emulate_power_cut",
546 S_IWUSR, d->dfs_dir,
547 (void *)ubi_num,
548 &dfs_fops);
549
550 d->dfs_power_cut_min = debugfs_create_file("tst_emulate_power_cut_min",
551 S_IWUSR, d->dfs_dir,
552 (void *)ubi_num, &dfs_fops);
553
554 d->dfs_power_cut_max = debugfs_create_file("tst_emulate_power_cut_max",
555 S_IWUSR, d->dfs_dir,
556 (void *)ubi_num, &dfs_fops);
557
558 debugfs_create_file("detailed_erase_block_info", S_IRUSR, d->dfs_dir,
559 (void *)ubi_num, &eraseblk_count_fops);
560
561 return 0;
562}
563
564/**
565 * dbg_debug_exit_dev - free all debugfs files corresponding to device @ubi
566 * @ubi: UBI device description object
567 */
568void ubi_debugfs_exit_dev(struct ubi_device *ubi)
569{
570 if (IS_ENABLED(CONFIG_DEBUG_FS))
571 debugfs_remove_recursive(ubi->dbg.dfs_dir);
572}
573
574/**
575 * ubi_dbg_power_cut - emulate a power cut if it is time to do so
576 * @ubi: UBI device description object
577 * @caller: Flags set to indicate from where the function is being called
578 *
579 * Returns non-zero if a power cut was emulated, zero if not.
580 */
581int ubi_dbg_power_cut(struct ubi_device *ubi, int caller)
582{
583 unsigned int range;
584
585 if ((ubi->dbg.emulate_power_cut & caller) == 0)
586 return 0;
587
588 if (ubi->dbg.power_cut_counter == 0) {
589 ubi->dbg.power_cut_counter = ubi->dbg.power_cut_min;
590
591 if (ubi->dbg.power_cut_max > ubi->dbg.power_cut_min) {
592 range = ubi->dbg.power_cut_max - ubi->dbg.power_cut_min;
593 ubi->dbg.power_cut_counter += prandom_u32() % range;
594 }
595 return 0;
596 }
597
598 ubi->dbg.power_cut_counter--;
599 if (ubi->dbg.power_cut_counter)
600 return 0;
601
602 ubi_msg(ubi, "XXXXXXXXXXXXXXX emulating a power cut XXXXXXXXXXXXXXXX");
603 ubi_ro_mode(ubi);
604 return 1;
605}