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 */
34void 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);
54out:
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 */
63void 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 */
82void 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 */
107void 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 */
138void 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 */
170void 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 */
188void 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 */
204void 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 */
224static 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 */
232int 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 */
252void 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 */
259static 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
316out:
317	ubi_put_device(ubi);
318	return count;
319}
320
321/* Write an UBI debugfs file */
322static 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
383out:
384	ubi_put_device(ubi);
385	return count;
386}
387
388/* File operations for all UBI debugfs files */
389static 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 */
404int 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
495out_remove:
496	debugfs_remove_recursive(d->dfs_dir);
497out:
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 */
508void 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 */
521int 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