xref: /linux/drivers/mtd/ubi/debug.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 
26 
27 /**
28  * ubi_dump_flash - dump a region of flash.
29  * @ubi: UBI device description object
30  * @pnum: the physical eraseblock number to dump
31  * @offset: the starting offset within the physical eraseblock to dump
32  * @len: the length of the region to dump
33  */
34 void ubi_dump_flash(struct ubi_device *ubi, int pnum, int offset, int len)
35 {
36 	int err;
37 	size_t read;
38 	void *buf;
39 	loff_t addr = (loff_t)pnum * ubi->peb_size + offset;
40 
41 	buf = vmalloc(len);
42 	if (!buf)
43 		return;
44 	err = mtd_read(ubi->mtd, addr, len, &read, buf);
45 	if (err && err != -EUCLEAN) {
46 		ubi_err(ubi, "err %d while reading %d bytes from PEB %d:%d, read %zd bytes",
47 			err, len, pnum, offset, read);
48 		goto out;
49 	}
50 
51 	ubi_msg(ubi, "dumping %d bytes of data from PEB %d, offset %d",
52 		len, pnum, offset);
53 	print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, buf, len, 1);
54 out:
55 	vfree(buf);
56 	return;
57 }
58 
59 /**
60  * ubi_dump_ec_hdr - dump an erase counter header.
61  * @ec_hdr: the erase counter header to dump
62  */
63 void ubi_dump_ec_hdr(const struct ubi_ec_hdr *ec_hdr)
64 {
65 	pr_err("Erase counter header dump:\n");
66 	pr_err("\tmagic          %#08x\n", be32_to_cpu(ec_hdr->magic));
67 	pr_err("\tversion        %d\n", (int)ec_hdr->version);
68 	pr_err("\tec             %llu\n", (long long)be64_to_cpu(ec_hdr->ec));
69 	pr_err("\tvid_hdr_offset %d\n", be32_to_cpu(ec_hdr->vid_hdr_offset));
70 	pr_err("\tdata_offset    %d\n", be32_to_cpu(ec_hdr->data_offset));
71 	pr_err("\timage_seq      %d\n", be32_to_cpu(ec_hdr->image_seq));
72 	pr_err("\thdr_crc        %#08x\n", be32_to_cpu(ec_hdr->hdr_crc));
73 	pr_err("erase counter header hexdump:\n");
74 	print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
75 		       ec_hdr, UBI_EC_HDR_SIZE, 1);
76 }
77 
78 /**
79  * ubi_dump_vid_hdr - dump a volume identifier header.
80  * @vid_hdr: the volume identifier header to dump
81  */
82 void ubi_dump_vid_hdr(const struct ubi_vid_hdr *vid_hdr)
83 {
84 	pr_err("Volume identifier header dump:\n");
85 	pr_err("\tmagic     %08x\n", be32_to_cpu(vid_hdr->magic));
86 	pr_err("\tversion   %d\n",  (int)vid_hdr->version);
87 	pr_err("\tvol_type  %d\n",  (int)vid_hdr->vol_type);
88 	pr_err("\tcopy_flag %d\n",  (int)vid_hdr->copy_flag);
89 	pr_err("\tcompat    %d\n",  (int)vid_hdr->compat);
90 	pr_err("\tvol_id    %d\n",  be32_to_cpu(vid_hdr->vol_id));
91 	pr_err("\tlnum      %d\n",  be32_to_cpu(vid_hdr->lnum));
92 	pr_err("\tdata_size %d\n",  be32_to_cpu(vid_hdr->data_size));
93 	pr_err("\tused_ebs  %d\n",  be32_to_cpu(vid_hdr->used_ebs));
94 	pr_err("\tdata_pad  %d\n",  be32_to_cpu(vid_hdr->data_pad));
95 	pr_err("\tsqnum     %llu\n",
96 		(unsigned long long)be64_to_cpu(vid_hdr->sqnum));
97 	pr_err("\thdr_crc   %08x\n", be32_to_cpu(vid_hdr->hdr_crc));
98 	pr_err("Volume identifier header hexdump:\n");
99 	print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
100 		       vid_hdr, UBI_VID_HDR_SIZE, 1);
101 }
102 
103 /**
104  * ubi_dump_vol_info - dump volume information.
105  * @vol: UBI volume description object
106  */
107 void ubi_dump_vol_info(const struct ubi_volume *vol)
108 {
109 	pr_err("Volume information dump:\n");
110 	pr_err("\tvol_id          %d\n", vol->vol_id);
111 	pr_err("\treserved_pebs   %d\n", vol->reserved_pebs);
112 	pr_err("\talignment       %d\n", vol->alignment);
113 	pr_err("\tdata_pad        %d\n", vol->data_pad);
114 	pr_err("\tvol_type        %d\n", vol->vol_type);
115 	pr_err("\tname_len        %d\n", vol->name_len);
116 	pr_err("\tusable_leb_size %d\n", vol->usable_leb_size);
117 	pr_err("\tused_ebs        %d\n", vol->used_ebs);
118 	pr_err("\tused_bytes      %lld\n", vol->used_bytes);
119 	pr_err("\tlast_eb_bytes   %d\n", vol->last_eb_bytes);
120 	pr_err("\tcorrupted       %d\n", vol->corrupted);
121 	pr_err("\tupd_marker      %d\n", vol->upd_marker);
122 
123 	if (vol->name_len <= UBI_VOL_NAME_MAX &&
124 	    strnlen(vol->name, vol->name_len + 1) == vol->name_len) {
125 		pr_err("\tname            %s\n", vol->name);
126 	} else {
127 		pr_err("\t1st 5 characters of name: %c%c%c%c%c\n",
128 		       vol->name[0], vol->name[1], vol->name[2],
129 		       vol->name[3], vol->name[4]);
130 	}
131 }
132 
133 /**
134  * ubi_dump_vtbl_record - dump a &struct ubi_vtbl_record object.
135  * @r: the object to dump
136  * @idx: volume table index
137  */
138 void ubi_dump_vtbl_record(const struct ubi_vtbl_record *r, int idx)
139 {
140 	int name_len = be16_to_cpu(r->name_len);
141 
142 	pr_err("Volume table record %d dump:\n", idx);
143 	pr_err("\treserved_pebs   %d\n", be32_to_cpu(r->reserved_pebs));
144 	pr_err("\talignment       %d\n", be32_to_cpu(r->alignment));
145 	pr_err("\tdata_pad        %d\n", be32_to_cpu(r->data_pad));
146 	pr_err("\tvol_type        %d\n", (int)r->vol_type);
147 	pr_err("\tupd_marker      %d\n", (int)r->upd_marker);
148 	pr_err("\tname_len        %d\n", name_len);
149 
150 	if (r->name[0] == '\0') {
151 		pr_err("\tname            NULL\n");
152 		return;
153 	}
154 
155 	if (name_len <= UBI_VOL_NAME_MAX &&
156 	    strnlen(&r->name[0], name_len + 1) == name_len) {
157 		pr_err("\tname            %s\n", &r->name[0]);
158 	} else {
159 		pr_err("\t1st 5 characters of name: %c%c%c%c%c\n",
160 			r->name[0], r->name[1], r->name[2], r->name[3],
161 			r->name[4]);
162 	}
163 	pr_err("\tcrc             %#08x\n", be32_to_cpu(r->crc));
164 }
165 
166 /**
167  * ubi_dump_av - dump a &struct ubi_ainf_volume object.
168  * @av: the object to dump
169  */
170 void ubi_dump_av(const struct ubi_ainf_volume *av)
171 {
172 	pr_err("Volume attaching information dump:\n");
173 	pr_err("\tvol_id         %d\n", av->vol_id);
174 	pr_err("\thighest_lnum   %d\n", av->highest_lnum);
175 	pr_err("\tleb_count      %d\n", av->leb_count);
176 	pr_err("\tcompat         %d\n", av->compat);
177 	pr_err("\tvol_type       %d\n", av->vol_type);
178 	pr_err("\tused_ebs       %d\n", av->used_ebs);
179 	pr_err("\tlast_data_size %d\n", av->last_data_size);
180 	pr_err("\tdata_pad       %d\n", av->data_pad);
181 }
182 
183 /**
184  * ubi_dump_aeb - dump a &struct ubi_ainf_peb object.
185  * @aeb: the object to dump
186  * @type: object type: 0 - not corrupted, 1 - corrupted
187  */
188 void ubi_dump_aeb(const struct ubi_ainf_peb *aeb, int type)
189 {
190 	pr_err("eraseblock attaching information dump:\n");
191 	pr_err("\tec       %d\n", aeb->ec);
192 	pr_err("\tpnum     %d\n", aeb->pnum);
193 	if (type == 0) {
194 		pr_err("\tlnum     %d\n", aeb->lnum);
195 		pr_err("\tscrub    %d\n", aeb->scrub);
196 		pr_err("\tsqnum    %llu\n", aeb->sqnum);
197 	}
198 }
199 
200 /**
201  * ubi_dump_mkvol_req - dump a &struct ubi_mkvol_req object.
202  * @req: the object to dump
203  */
204 void ubi_dump_mkvol_req(const struct ubi_mkvol_req *req)
205 {
206 	char nm[17];
207 
208 	pr_err("Volume creation request dump:\n");
209 	pr_err("\tvol_id    %d\n",   req->vol_id);
210 	pr_err("\talignment %d\n",   req->alignment);
211 	pr_err("\tbytes     %lld\n", (long long)req->bytes);
212 	pr_err("\tvol_type  %d\n",   req->vol_type);
213 	pr_err("\tname_len  %d\n",   req->name_len);
214 
215 	memcpy(nm, req->name, 16);
216 	nm[16] = 0;
217 	pr_err("\t1st 16 characters of name: %s\n", nm);
218 }
219 
220 /*
221  * Root directory for UBI stuff in debugfs. Contains sub-directories which
222  * contain the stuff specific to particular UBI devices.
223  */
224 static struct dentry *dfs_rootdir;
225 
226 /**
227  * ubi_debugfs_init - create UBI debugfs directory.
228  *
229  * Create UBI debugfs directory. Returns zero in case of success and a negative
230  * error code in case of failure.
231  */
232 int ubi_debugfs_init(void)
233 {
234 	if (!IS_ENABLED(CONFIG_DEBUG_FS))
235 		return 0;
236 
237 	dfs_rootdir = debugfs_create_dir("ubi", NULL);
238 	if (IS_ERR_OR_NULL(dfs_rootdir)) {
239 		int err = dfs_rootdir ? -ENODEV : PTR_ERR(dfs_rootdir);
240 
241 		pr_err("UBI error: cannot create \"ubi\" debugfs directory, error %d\n",
242 		       err);
243 		return err;
244 	}
245 
246 	return 0;
247 }
248 
249 /**
250  * ubi_debugfs_exit - remove UBI debugfs directory.
251  */
252 void ubi_debugfs_exit(void)
253 {
254 	if (IS_ENABLED(CONFIG_DEBUG_FS))
255 		debugfs_remove(dfs_rootdir);
256 }
257 
258 /* Read an UBI debugfs file */
259 static ssize_t dfs_file_read(struct file *file, char __user *user_buf,
260 			     size_t count, loff_t *ppos)
261 {
262 	unsigned long ubi_num = (unsigned long)file->private_data;
263 	struct dentry *dent = file->f_path.dentry;
264 	struct ubi_device *ubi;
265 	struct ubi_debug_info *d;
266 	char buf[8];
267 	int val;
268 
269 	ubi = ubi_get_device(ubi_num);
270 	if (!ubi)
271 		return -ENODEV;
272 	d = &ubi->dbg;
273 
274 	if (dent == d->dfs_chk_gen)
275 		val = d->chk_gen;
276 	else if (dent == d->dfs_chk_io)
277 		val = d->chk_io;
278 	else if (dent == d->dfs_chk_fastmap)
279 		val = d->chk_fastmap;
280 	else if (dent == d->dfs_disable_bgt)
281 		val = d->disable_bgt;
282 	else if (dent == d->dfs_emulate_bitflips)
283 		val = d->emulate_bitflips;
284 	else if (dent == d->dfs_emulate_io_failures)
285 		val = d->emulate_io_failures;
286 	else if (dent == d->dfs_emulate_power_cut) {
287 		snprintf(buf, sizeof(buf), "%u\n", d->emulate_power_cut);
288 		count = simple_read_from_buffer(user_buf, count, ppos,
289 						buf, strlen(buf));
290 		goto out;
291 	} else if (dent == d->dfs_power_cut_min) {
292 		snprintf(buf, sizeof(buf), "%u\n", d->power_cut_min);
293 		count = simple_read_from_buffer(user_buf, count, ppos,
294 						buf, strlen(buf));
295 		goto out;
296 	} else if (dent == d->dfs_power_cut_max) {
297 		snprintf(buf, sizeof(buf), "%u\n", d->power_cut_max);
298 		count = simple_read_from_buffer(user_buf, count, ppos,
299 						buf, strlen(buf));
300 		goto out;
301 	}
302 	else {
303 		count = -EINVAL;
304 		goto out;
305 	}
306 
307 	if (val)
308 		buf[0] = '1';
309 	else
310 		buf[0] = '0';
311 	buf[1] = '\n';
312 	buf[2] = 0x00;
313 
314 	count = simple_read_from_buffer(user_buf, count, ppos, buf, 2);
315 
316 out:
317 	ubi_put_device(ubi);
318 	return count;
319 }
320 
321 /* Write an UBI debugfs file */
322 static ssize_t dfs_file_write(struct file *file, const char __user *user_buf,
323 			      size_t count, loff_t *ppos)
324 {
325 	unsigned long ubi_num = (unsigned long)file->private_data;
326 	struct dentry *dent = file->f_path.dentry;
327 	struct ubi_device *ubi;
328 	struct ubi_debug_info *d;
329 	size_t buf_size;
330 	char buf[8] = {0};
331 	int val;
332 
333 	ubi = ubi_get_device(ubi_num);
334 	if (!ubi)
335 		return -ENODEV;
336 	d = &ubi->dbg;
337 
338 	buf_size = min_t(size_t, count, (sizeof(buf) - 1));
339 	if (copy_from_user(buf, user_buf, buf_size)) {
340 		count = -EFAULT;
341 		goto out;
342 	}
343 
344 	if (dent == d->dfs_power_cut_min) {
345 		if (kstrtouint(buf, 0, &d->power_cut_min) != 0)
346 			count = -EINVAL;
347 		goto out;
348 	} else if (dent == d->dfs_power_cut_max) {
349 		if (kstrtouint(buf, 0, &d->power_cut_max) != 0)
350 			count = -EINVAL;
351 		goto out;
352 	} else if (dent == d->dfs_emulate_power_cut) {
353 		if (kstrtoint(buf, 0, &val) != 0)
354 			count = -EINVAL;
355 		d->emulate_power_cut = val;
356 		goto out;
357 	}
358 
359 	if (buf[0] == '1')
360 		val = 1;
361 	else if (buf[0] == '0')
362 		val = 0;
363 	else {
364 		count = -EINVAL;
365 		goto out;
366 	}
367 
368 	if (dent == d->dfs_chk_gen)
369 		d->chk_gen = val;
370 	else if (dent == d->dfs_chk_io)
371 		d->chk_io = val;
372 	else if (dent == d->dfs_chk_fastmap)
373 		d->chk_fastmap = val;
374 	else if (dent == d->dfs_disable_bgt)
375 		d->disable_bgt = val;
376 	else if (dent == d->dfs_emulate_bitflips)
377 		d->emulate_bitflips = val;
378 	else if (dent == d->dfs_emulate_io_failures)
379 		d->emulate_io_failures = val;
380 	else
381 		count = -EINVAL;
382 
383 out:
384 	ubi_put_device(ubi);
385 	return count;
386 }
387 
388 /* File operations for all UBI debugfs files */
389 static const struct file_operations dfs_fops = {
390 	.read   = dfs_file_read,
391 	.write  = dfs_file_write,
392 	.open	= simple_open,
393 	.llseek = no_llseek,
394 	.owner  = THIS_MODULE,
395 };
396 
397 /**
398  * ubi_debugfs_init_dev - initialize debugfs for an UBI device.
399  * @ubi: UBI device description object
400  *
401  * This function creates all debugfs files for UBI device @ubi. Returns zero in
402  * case of success and a negative error code in case of failure.
403  */
404 int ubi_debugfs_init_dev(struct ubi_device *ubi)
405 {
406 	int err, n;
407 	unsigned long ubi_num = ubi->ubi_num;
408 	const char *fname;
409 	struct dentry *dent;
410 	struct ubi_debug_info *d = &ubi->dbg;
411 
412 	if (!IS_ENABLED(CONFIG_DEBUG_FS))
413 		return 0;
414 
415 	n = snprintf(d->dfs_dir_name, UBI_DFS_DIR_LEN + 1, UBI_DFS_DIR_NAME,
416 		     ubi->ubi_num);
417 	if (n == UBI_DFS_DIR_LEN) {
418 		/* The array size is too small */
419 		fname = UBI_DFS_DIR_NAME;
420 		dent = ERR_PTR(-EINVAL);
421 		goto out;
422 	}
423 
424 	fname = d->dfs_dir_name;
425 	dent = debugfs_create_dir(fname, dfs_rootdir);
426 	if (IS_ERR_OR_NULL(dent))
427 		goto out;
428 	d->dfs_dir = dent;
429 
430 	fname = "chk_gen";
431 	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
432 				   &dfs_fops);
433 	if (IS_ERR_OR_NULL(dent))
434 		goto out_remove;
435 	d->dfs_chk_gen = dent;
436 
437 	fname = "chk_io";
438 	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
439 				   &dfs_fops);
440 	if (IS_ERR_OR_NULL(dent))
441 		goto out_remove;
442 	d->dfs_chk_io = dent;
443 
444 	fname = "chk_fastmap";
445 	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
446 				   &dfs_fops);
447 	if (IS_ERR_OR_NULL(dent))
448 		goto out_remove;
449 	d->dfs_chk_fastmap = dent;
450 
451 	fname = "tst_disable_bgt";
452 	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
453 				   &dfs_fops);
454 	if (IS_ERR_OR_NULL(dent))
455 		goto out_remove;
456 	d->dfs_disable_bgt = dent;
457 
458 	fname = "tst_emulate_bitflips";
459 	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
460 				   &dfs_fops);
461 	if (IS_ERR_OR_NULL(dent))
462 		goto out_remove;
463 	d->dfs_emulate_bitflips = dent;
464 
465 	fname = "tst_emulate_io_failures";
466 	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
467 				   &dfs_fops);
468 	if (IS_ERR_OR_NULL(dent))
469 		goto out_remove;
470 	d->dfs_emulate_io_failures = dent;
471 
472 	fname = "tst_emulate_power_cut";
473 	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
474 				   &dfs_fops);
475 	if (IS_ERR_OR_NULL(dent))
476 		goto out_remove;
477 	d->dfs_emulate_power_cut = dent;
478 
479 	fname = "tst_emulate_power_cut_min";
480 	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
481 				   &dfs_fops);
482 	if (IS_ERR_OR_NULL(dent))
483 		goto out_remove;
484 	d->dfs_power_cut_min = dent;
485 
486 	fname = "tst_emulate_power_cut_max";
487 	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
488 				   &dfs_fops);
489 	if (IS_ERR_OR_NULL(dent))
490 		goto out_remove;
491 	d->dfs_power_cut_max = dent;
492 
493 	return 0;
494 
495 out_remove:
496 	debugfs_remove_recursive(d->dfs_dir);
497 out:
498 	err = dent ? PTR_ERR(dent) : -ENODEV;
499 	ubi_err(ubi, "cannot create \"%s\" debugfs file or directory, error %d\n",
500 		fname, err);
501 	return err;
502 }
503 
504 /**
505  * dbg_debug_exit_dev - free all debugfs files corresponding to device @ubi
506  * @ubi: UBI device description object
507  */
508 void ubi_debugfs_exit_dev(struct ubi_device *ubi)
509 {
510 	if (IS_ENABLED(CONFIG_DEBUG_FS))
511 		debugfs_remove_recursive(ubi->dbg.dfs_dir);
512 }
513 
514 /**
515  * ubi_dbg_power_cut - emulate a power cut if it is time to do so
516  * @ubi: UBI device description object
517  * @caller: Flags set to indicate from where the function is being called
518  *
519  * Returns non-zero if a power cut was emulated, zero if not.
520  */
521 int ubi_dbg_power_cut(struct ubi_device *ubi, int caller)
522 {
523 	unsigned int range;
524 
525 	if ((ubi->dbg.emulate_power_cut & caller) == 0)
526 		return 0;
527 
528 	if (ubi->dbg.power_cut_counter == 0) {
529 		ubi->dbg.power_cut_counter = ubi->dbg.power_cut_min;
530 
531 		if (ubi->dbg.power_cut_max > ubi->dbg.power_cut_min) {
532 			range = ubi->dbg.power_cut_max - ubi->dbg.power_cut_min;
533 			ubi->dbg.power_cut_counter += prandom_u32() % range;
534 		}
535 		return 0;
536 	}
537 
538 	ubi->dbg.power_cut_counter--;
539 	if (ubi->dbg.power_cut_counter)
540 		return 0;
541 
542 	ubi_msg(ubi, "XXXXXXXXXXXXXXX emulating a power cut XXXXXXXXXXXXXXXX");
543 	ubi_ro_mode(ubi);
544 	return 1;
545 }
546