kernel/drivers/mtd/ubi/debug.c

   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 }