xref: /linux/drivers/mtd/ubi/debug.c (revision 3f0a50f345f78183f6e9b39c2f45ca5dcaa511ca)
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 	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  */
127 void 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  */
159 void 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  */
177 void 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  */
193 void 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  */
213 static 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  */
221 int 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  */
241 void 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 */
248 static 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 
305 out:
306 	ubi_put_device(ubi);
307 	return count;
308 }
309 
310 /* Write an UBI debugfs file */
311 static 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 
373 out:
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  */
381 static 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  */
392 static 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  */
405 static 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 
417 static void eraseblk_count_seq_stop(struct seq_file *s, void *v)
418 {
419 }
420 
421 static 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 
453 static 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 
460 static 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 
478 static 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 
488 static 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  */
503 int 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  * ubi_debugfs_exit_dev - free all debugfs files corresponding to device @ubi
566  * @ubi: UBI device description object
567  */
568 void 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  */
581 int 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 }
606