fs/dlm/debug_fs.c

   1 /******************************************************************************
   2 *******************************************************************************
   3 **
   4 **  Copyright (C) 2005-2009 Red Hat, Inc.  All rights reserved.
   5 **
   6 **  This copyrighted material is made available to anyone wishing to use,
   7 **  modify, copy, or redistribute it subject to the terms and conditions
   8 **  of the GNU General Public License v.2.
   9 **
  10 *******************************************************************************
  11 ******************************************************************************/
  12
  13 #include <linux/pagemap.h>
  14 #include <linux/seq_file.h>
  15 #include <linux/module.h>
  16 #include <linux/ctype.h>
  17 #include <linux/debugfs.h>
  18 #include <linux/slab.h>
  19
  20 #include "dlm_internal.h"
  21 #include "lock.h"
  22
  23 #define DLM_DEBUG_BUF_LEN 4096
  24 static char debug_buf[DLM_DEBUG_BUF_LEN];
  25 static struct mutex debug_buf_lock;
  26
  27 static struct dentry *dlm_root;
  28
  29 static char *print_lockmode(int mode)
  30 {
  31         switch (mode) {
  32         case DLM_LOCK_IV:
  33                 return "--";
  34         case DLM_LOCK_NL:
  35                 return "NL";
  36         case DLM_LOCK_CR:
  37                 return "CR";
  38         case DLM_LOCK_CW:
  39                 return "CW";
  40         case DLM_LOCK_PR:
  41                 return "PR";
  42         case DLM_LOCK_PW:
  43                 return "PW";
  44         case DLM_LOCK_EX:
  45                 return "EX";
  46         default:
  47                 return "??";
  48         }
  49 }
  50
  51 static int print_format1_lock(struct seq_file *s, struct dlm_lkb *lkb,
  52                               struct dlm_rsb *res)
  53 {
  54         seq_printf(s, "%08x %s", lkb->lkb_id, print_lockmode(lkb->lkb_grmode));
  55
  56         if (lkb->lkb_status == DLM_LKSTS_CONVERT ||
  57             lkb->lkb_status == DLM_LKSTS_WAITING)
  58                 seq_printf(s, " (%s)", print_lockmode(lkb->lkb_rqmode));
  59
  60         if (lkb->lkb_nodeid) {
  61                 if (lkb->lkb_nodeid != res->res_nodeid)
  62                         seq_printf(s, " Remote: %3d %08x", lkb->lkb_nodeid,
  63                                    lkb->lkb_remid);
  64                 else
  65                         seq_printf(s, " Master:     %08x", lkb->lkb_remid);
  66         }
  67
  68         if (lkb->lkb_wait_type)
  69                 seq_printf(s, " wait_type: %d", lkb->lkb_wait_type);
  70
  71         return seq_printf(s, "\n");
  72 }
  73
  74 static int print_format1(struct dlm_rsb *res, struct seq_file *s)
  75 {
  76         struct dlm_lkb *lkb;
  77         int i, lvblen = res->res_ls->ls_lvblen, recover_list, root_list;
  78         int rv;
  79
  80         lock_rsb(res);
  81
  82         rv = seq_printf(s, "\nResource %p Name (len=%d) \"",
  83                         res, res->res_length);
  84         if (rv)
  85                 goto out;
  86
  87         for (i = 0; i < res->res_length; i++) {
  88                 if (isprint(res->res_name[i]))
  89                         seq_printf(s, "%c", res->res_name[i]);
  90                 else
  91                         seq_printf(s, "%c", '.');
  92         }
  93
  94         if (res->res_nodeid > 0)
  95                 rv = seq_printf(s, "\"  \nLocal Copy, Master is node %d\n",
  96                                 res->res_nodeid);
  97         else if (res->res_nodeid == 0)
  98                 rv = seq_printf(s, "\"  \nMaster Copy\n");
  99         else if (res->res_nodeid == -1)
 100                 rv = seq_printf(s, "\"  \nLooking up master (lkid %x)\n",
 101                                 res->res_first_lkid);
 102         else
 103                 rv = seq_printf(s, "\"  \nInvalid master %d\n",
 104                                 res->res_nodeid);
 105         if (rv)
 106                 goto out;
 107
 108         /* Print the LVB: */
 109         if (res->res_lvbptr) {
 110                 seq_printf(s, "LVB: ");
 111                 for (i = 0; i < lvblen; i++) {
 112                         if (i == lvblen / 2)
 113                                 seq_printf(s, "\n     ");
 114                         seq_printf(s, "%02x ",
 115                                    (unsigned char) res->res_lvbptr[i]);
 116                 }
 117                 if (rsb_flag(res, RSB_VALNOTVALID))
 118                         seq_printf(s, " (INVALID)");
 119                 rv = seq_printf(s, "\n");
 120                 if (rv)
 121                         goto out;
 122         }
 123
 124         root_list = !list_empty(&res->res_root_list);
 125         recover_list = !list_empty(&res->res_recover_list);
 126
 127         if (root_list || recover_list) {
 128                 rv = seq_printf(s, "Recovery: root %d recover %d flags %lx "
 129                                 "count %d\n", root_list, recover_list,
 130                                 res->res_flags, res->res_recover_locks_count);
 131                 if (rv)
 132                         goto out;
 133         }
 134
 135         /* Print the locks attached to this resource */
 136         seq_printf(s, "Granted Queue\n");
 137         list_for_each_entry(lkb, &res->res_grantqueue, lkb_statequeue) {
 138                 rv = print_format1_lock(s, lkb, res);
 139                 if (rv)
 140                         goto out;
 141         }
 142
 143         seq_printf(s, "Conversion Queue\n");
 144         list_for_each_entry(lkb, &res->res_convertqueue, lkb_statequeue) {
 145                 rv = print_format1_lock(s, lkb, res);
 146                 if (rv)
 147                         goto out;
 148         }
 149
 150         seq_printf(s, "Waiting Queue\n");
 151         list_for_each_entry(lkb, &res->res_waitqueue, lkb_statequeue) {
 152                 rv = print_format1_lock(s, lkb, res);
 153                 if (rv)
 154                         goto out;
 155         }
 156
 157         if (list_empty(&res->res_lookup))
 158                 goto out;
 159
 160         seq_printf(s, "Lookup Queue\n");
 161         list_for_each_entry(lkb, &res->res_lookup, lkb_rsb_lookup) {
 162                 rv = seq_printf(s, "%08x %s", lkb->lkb_id,
 163                                 print_lockmode(lkb->lkb_rqmode));
 164                 if (lkb->lkb_wait_type)
 165                         seq_printf(s, " wait_type: %d", lkb->lkb_wait_type);
 166                 rv = seq_printf(s, "\n");
 167         }
 168  out:
 169         unlock_rsb(res);
 170         return rv;
 171 }
 172
 173 static int print_format2_lock(struct seq_file *s, struct dlm_lkb *lkb,
 174                               struct dlm_rsb *r)
 175 {
 176         u64 xid = 0;
 177         u64 us;
 178         int rv;
 179
 180         if (lkb->lkb_flags & DLM_IFL_USER) {
 181                 if (lkb->lkb_ua)
 182                         xid = lkb->lkb_ua->xid;
 183         }
 184
 185         /* microseconds since lkb was added to current queue */
 186         us = ktime_to_us(ktime_sub(ktime_get(), lkb->lkb_timestamp));
 187
 188         /* id nodeid remid pid xid exflags flags sts grmode rqmode time_us
 189            r_nodeid r_len r_name */
 190
 191         rv = seq_printf(s, "%x %d %x %u %llu %x %x %d %d %d %llu %u %d \"%s\"\n",
 192                         lkb->lkb_id,
 193                         lkb->lkb_nodeid,
 194                         lkb->lkb_remid,
 195                         lkb->lkb_ownpid,
 196                         (unsigned long long)xid,
 197                         lkb->lkb_exflags,
 198                         lkb->lkb_flags,
 199                         lkb->lkb_status,
 200                         lkb->lkb_grmode,
 201                         lkb->lkb_rqmode,
 202                         (unsigned long long)us,
 203                         r->res_nodeid,
 204                         r->res_length,
 205                         r->res_name);
 206         return rv;
 207 }
 208
 209 static int print_format2(struct dlm_rsb *r, struct seq_file *s)
 210 {
 211         struct dlm_lkb *lkb;
 212         int rv = 0;
 213
 214         lock_rsb(r);
 215
 216         list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
 217                 rv = print_format2_lock(s, lkb, r);
 218                 if (rv)
 219                         goto out;
 220         }
 221
 222         list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
 223                 rv = print_format2_lock(s, lkb, r);
 224                 if (rv)
 225                         goto out;
 226         }
 227
 228         list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue) {
 229                 rv = print_format2_lock(s, lkb, r);
 230                 if (rv)
 231                         goto out;
 232         }
 233  out:
 234         unlock_rsb(r);
 235         return rv;
 236 }
 237
 238 static int print_format3_lock(struct seq_file *s, struct dlm_lkb *lkb,
 239                               int rsb_lookup)
 240 {
 241         u64 xid = 0;
 242         int rv;
 243
 244         if (lkb->lkb_flags & DLM_IFL_USER) {
 245                 if (lkb->lkb_ua)
 246                         xid = lkb->lkb_ua->xid;
 247         }
 248
 249         rv = seq_printf(s, "lkb %x %d %x %u %llu %x %x %d %d %d %d %d %d %u %llu %llu\n",
 250                         lkb->lkb_id,
 251                         lkb->lkb_nodeid,
 252                         lkb->lkb_remid,
 253                         lkb->lkb_ownpid,
 254                         (unsigned long long)xid,
 255                         lkb->lkb_exflags,
 256                         lkb->lkb_flags,
 257                         lkb->lkb_status,
 258                         lkb->lkb_grmode,
 259                         lkb->lkb_rqmode,
 260                         lkb->lkb_last_bast.mode,
 261                         rsb_lookup,
 262                         lkb->lkb_wait_type,
 263                         lkb->lkb_lvbseq,
 264                         (unsigned long long)ktime_to_ns(lkb->lkb_timestamp),
 265                         (unsigned long long)ktime_to_ns(lkb->lkb_last_bast_time));
 266         return rv;
 267 }
 268
 269 static int print_format3(struct dlm_rsb *r, struct seq_file *s)
 270 {
 271         struct dlm_lkb *lkb;
 272         int i, lvblen = r->res_ls->ls_lvblen;
 273         int print_name = 1;
 274         int rv;
 275
 276         lock_rsb(r);
 277
 278         rv = seq_printf(s, "rsb %p %d %x %lx %d %d %u %d ",
 279                         r,
 280                         r->res_nodeid,
 281                         r->res_first_lkid,
 282                         r->res_flags,
 283                         !list_empty(&r->res_root_list),
 284                         !list_empty(&r->res_recover_list),
 285                         r->res_recover_locks_count,
 286                         r->res_length);
 287         if (rv)
 288                 goto out;
 289
 290         for (i = 0; i < r->res_length; i++) {
 291                 if (!isascii(r->res_name[i]) || !isprint(r->res_name[i]))
 292                         print_name = 0;
 293         }
 294
 295         seq_printf(s, "%s", print_name ? "str " : "hex");
 296
 297         for (i = 0; i < r->res_length; i++) {
 298                 if (print_name)
 299                         seq_printf(s, "%c", r->res_name[i]);
 300                 else
 301                         seq_printf(s, " %02x", (unsigned char)r->res_name[i]);
 302         }
 303         rv = seq_printf(s, "\n");
 304         if (rv)
 305                 goto out;
 306
 307         if (!r->res_lvbptr)
 308                 goto do_locks;
 309
 310         seq_printf(s, "lvb %u %d", r->res_lvbseq, lvblen);
 311
 312         for (i = 0; i < lvblen; i++)
 313                 seq_printf(s, " %02x", (unsigned char)r->res_lvbptr[i]);
 314         rv = seq_printf(s, "\n");
 315         if (rv)
 316                 goto out;
 317
 318  do_locks:
 319         list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
 320                 rv = print_format3_lock(s, lkb, 0);
 321                 if (rv)
 322                         goto out;
 323         }
 324
 325         list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
 326                 rv = print_format3_lock(s, lkb, 0);
 327                 if (rv)
 328                         goto out;
 329         }
 330
 331         list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue) {
 332                 rv = print_format3_lock(s, lkb, 0);
 333                 if (rv)
 334                         goto out;
 335         }
 336
 337         list_for_each_entry(lkb, &r->res_lookup, lkb_rsb_lookup) {
 338                 rv = print_format3_lock(s, lkb, 1);
 339                 if (rv)
 340                         goto out;
 341         }
 342  out:
 343         unlock_rsb(r);
 344         return rv;
 345 }
 346
 347 struct rsbtbl_iter {
 348         struct dlm_rsb *rsb;
 349         unsigned bucket;
 350         int format;
 351         int header;
 352 };
 353
 354 /* seq_printf returns -1 if the buffer is full, and 0 otherwise.
 355    If the buffer is full, seq_printf can be called again, but it
 356    does nothing and just returns -1.  So, the these printing routines
 357    periodically check the return value to avoid wasting too much time
 358    trying to print to a full buffer. */
 359
 360 static int table_seq_show(struct seq_file *seq, void *iter_ptr)
 361 {
 362         struct rsbtbl_iter *ri = iter_ptr;
 363         int rv = 0;
 364
 365         switch (ri->format) {
 366         case 1:
 367                 rv = print_format1(ri->rsb, seq);
 368                 break;
 369         case 2:
 370                 if (ri->header) {
 371                         seq_printf(seq, "id nodeid remid pid xid exflags "
 372                                         "flags sts grmode rqmode time_ms "
 373                                         "r_nodeid r_len r_name\n");
 374                         ri->header = 0;
 375                 }
 376                 rv = print_format2(ri->rsb, seq);
 377                 break;
 378         case 3:
 379                 if (ri->header) {
 380                         seq_printf(seq, "version rsb 1.1 lvb 1.1 lkb 1.1\n");
 381                         ri->header = 0;
 382                 }
 383                 rv = print_format3(ri->rsb, seq);
 384                 break;
 385         }
 386
 387         return rv;
 388 }
 389
 390 static const struct seq_operations format1_seq_ops;
 391 static const struct seq_operations format2_seq_ops;
 392 static const struct seq_operations format3_seq_ops;
 393
 394 static void *table_seq_start(struct seq_file *seq, loff_t *pos)
 395 {
 396         struct rb_node *node;
 397         struct dlm_ls *ls = seq->private;
 398         struct rsbtbl_iter *ri;
 399         struct dlm_rsb *r;
 400         loff_t n = *pos;
 401         unsigned bucket, entry;
 402
 403         bucket = n >> 32;
 404         entry = n & ((1LL << 32) - 1);
 405
 406         if (bucket >= ls->ls_rsbtbl_size)
 407                 return NULL;
 408
 409         ri = kzalloc(sizeof(struct rsbtbl_iter), GFP_NOFS);
 410         if (!ri)
 411                 return NULL;
 412         if (n == 0)
 413                 ri->header = 1;
 414         if (seq->op == &format1_seq_ops)
 415                 ri->format = 1;
 416         if (seq->op == &format2_seq_ops)
 417                 ri->format = 2;
 418         if (seq->op == &format3_seq_ops)
 419                 ri->format = 3;
 420
 421         spin_lock(&ls->ls_rsbtbl[bucket].lock);
 422         if (!RB_EMPTY_ROOT(&ls->ls_rsbtbl[bucket].keep)) {
 423                 for (node = rb_first(&ls->ls_rsbtbl[bucket].keep); node;
 424                      node = rb_next(node)) {
 425                         r = rb_entry(node, struct dlm_rsb, res_hashnode);
 426                         if (!entry--) {
 427                                 dlm_hold_rsb(r);
 428                                 ri->rsb = r;
 429                                 ri->bucket = bucket;
 430                                 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
 431                                 return ri;
 432                         }
 433                 }
 434         }
 435         spin_unlock(&ls->ls_rsbtbl[bucket].lock);
 436
 437         /*
 438          * move to the first rsb in the next non-empty bucket
 439          */
 440
 441         /* zero the entry */
 442         n &= ~((1LL << 32) - 1);
 443
 444         while (1) {
 445                 bucket++;
 446                 n += 1LL << 32;
 447
 448                 if (bucket >= ls->ls_rsbtbl_size) {
 449                         kfree(ri);
 450                         return NULL;
 451                 }
 452
 453                 spin_lock(&ls->ls_rsbtbl[bucket].lock);
 454                 if (!RB_EMPTY_ROOT(&ls->ls_rsbtbl[bucket].keep)) {
 455                         node = rb_first(&ls->ls_rsbtbl[bucket].keep);
 456                         r = rb_entry(node, struct dlm_rsb, res_hashnode);
 457                         dlm_hold_rsb(r);
 458                         ri->rsb = r;
 459                         ri->bucket = bucket;
 460                         spin_unlock(&ls->ls_rsbtbl[bucket].lock);
 461                         *pos = n;
 462                         return ri;
 463                 }
 464                 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
 465         }
 466 }
 467
 468 static void *table_seq_next(struct seq_file *seq, void *iter_ptr, loff_t *pos)
 469 {
 470         struct dlm_ls *ls = seq->private;
 471         struct rsbtbl_iter *ri = iter_ptr;
 472         struct rb_node *next;
 473         struct dlm_rsb *r, *rp;
 474         loff_t n = *pos;
 475         unsigned bucket;
 476
 477         bucket = n >> 32;
 478
 479         /*
 480          * move to the next rsb in the same bucket
 481          */
 482
 483         spin_lock(&ls->ls_rsbtbl[bucket].lock);
 484         rp = ri->rsb;
 485         next = rb_next(&rp->res_hashnode);
 486
 487         if (next) {
 488                 r = rb_entry(next, struct dlm_rsb, res_hashnode);
 489                 dlm_hold_rsb(r);
 490                 ri->rsb = r;
 491                 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
 492                 dlm_put_rsb(rp);
 493                 ++*pos;
 494                 return ri;
 495         }
 496         spin_unlock(&ls->ls_rsbtbl[bucket].lock);
 497         dlm_put_rsb(rp);
 498
 499         /*
 500          * move to the first rsb in the next non-empty bucket
 501          */
 502
 503         /* zero the entry */
 504         n &= ~((1LL << 32) - 1);
 505
 506         while (1) {
 507                 bucket++;
 508                 n += 1LL << 32;
 509
 510                 if (bucket >= ls->ls_rsbtbl_size) {
 511                         kfree(ri);
 512                         return NULL;
 513                 }
 514
 515                 spin_lock(&ls->ls_rsbtbl[bucket].lock);
 516                 if (!RB_EMPTY_ROOT(&ls->ls_rsbtbl[bucket].keep)) {
 517                         next = rb_first(&ls->ls_rsbtbl[bucket].keep);
 518                         r = rb_entry(next, struct dlm_rsb, res_hashnode);
 519                         dlm_hold_rsb(r);
 520                         ri->rsb = r;
 521                         ri->bucket = bucket;
 522                         spin_unlock(&ls->ls_rsbtbl[bucket].lock);
 523                         *pos = n;
 524                         return ri;
 525                 }
 526                 spin_unlock(&ls->ls_rsbtbl[bucket].lock);
 527         }
 528 }
 529
 530 static void table_seq_stop(struct seq_file *seq, void *iter_ptr)
 531 {
 532         struct rsbtbl_iter *ri = iter_ptr;
 533
 534         if (ri) {
 535                 dlm_put_rsb(ri->rsb);
 536                 kfree(ri);
 537         }
 538 }
 539
 540 static const struct seq_operations format1_seq_ops = {
 541         .start = table_seq_start,
 542         .next  = table_seq_next,
 543         .stop  = table_seq_stop,
 544         .show  = table_seq_show,
 545 };
 546
 547 static const struct seq_operations format2_seq_ops = {
 548         .start = table_seq_start,
 549         .next  = table_seq_next,
 550         .stop  = table_seq_stop,
 551         .show  = table_seq_show,
 552 };
 553
 554 static const struct seq_operations format3_seq_ops = {
 555         .start = table_seq_start,
 556         .next  = table_seq_next,
 557         .stop  = table_seq_stop,
 558         .show  = table_seq_show,
 559 };
 560
 561 static const struct file_operations format1_fops;
 562 static const struct file_operations format2_fops;
 563 static const struct file_operations format3_fops;
 564
 565 static int table_open(struct inode *inode, struct file *file)
 566 {
 567         struct seq_file *seq;
 568         int ret = -1;
 569
 570         if (file->f_op == &format1_fops)
 571                 ret = seq_open(file, &format1_seq_ops);
 572         else if (file->f_op == &format2_fops)
 573                 ret = seq_open(file, &format2_seq_ops);
 574         else if (file->f_op == &format3_fops)
 575                 ret = seq_open(file, &format3_seq_ops);
 576
 577         if (ret)
 578                 return ret;
 579
 580         seq = file->private_data;
 581         seq->private = inode->i_private; /* the dlm_ls */
 582         return 0;
 583 }
 584
 585 static const struct file_operations format1_fops = {
 586         .owner   = THIS_MODULE,
 587         .open    = table_open,
 588         .read    = seq_read,
 589         .llseek  = seq_lseek,
 590         .release = seq_release
 591 };
 592
 593 static const struct file_operations format2_fops = {
 594         .owner   = THIS_MODULE,
 595         .open    = table_open,
 596         .read    = seq_read,
 597         .llseek  = seq_lseek,
 598         .release = seq_release
 599 };
 600
 601 static const struct file_operations format3_fops = {
 602         .owner   = THIS_MODULE,
 603         .open    = table_open,
 604         .read    = seq_read,
 605         .llseek  = seq_lseek,
 606         .release = seq_release
 607 };
 608
 609 /*
 610  * dump lkb's on the ls_waiters list
 611  */
 612 static ssize_t waiters_read(struct file *file, char __user *userbuf,
 613                             size_t count, loff_t *ppos)
 614 {
 615         struct dlm_ls *ls = file->private_data;
 616         struct dlm_lkb *lkb;
 617         size_t len = DLM_DEBUG_BUF_LEN, pos = 0, ret, rv;
 618
 619         mutex_lock(&debug_buf_lock);
 620         mutex_lock(&ls->ls_waiters_mutex);
 621         memset(debug_buf, 0, sizeof(debug_buf));
 622
 623         list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
 624                 ret = snprintf(debug_buf + pos, len - pos, "%x %d %d %s\n",
 625                                lkb->lkb_id, lkb->lkb_wait_type,
 626                                lkb->lkb_nodeid, lkb->lkb_resource->res_name);
 627                 if (ret >= len - pos)
 628                         break;
 629                 pos += ret;
 630         }
 631         mutex_unlock(&ls->ls_waiters_mutex);
 632
 633         rv = simple_read_from_buffer(userbuf, count, ppos, debug_buf, pos);
 634         mutex_unlock(&debug_buf_lock);
 635         return rv;
 636 }
 637
 638 static const struct file_operations waiters_fops = {
 639         .owner   = THIS_MODULE,
 640         .open    = simple_open,
 641         .read    = waiters_read,
 642         .llseek  = default_llseek,
 643 };
 644
 645 void dlm_delete_debug_file(struct dlm_ls *ls)
 646 {
 647         if (ls->ls_debug_rsb_dentry)
 648                 debugfs_remove(ls->ls_debug_rsb_dentry);
 649         if (ls->ls_debug_waiters_dentry)
 650                 debugfs_remove(ls->ls_debug_waiters_dentry);
 651         if (ls->ls_debug_locks_dentry)
 652                 debugfs_remove(ls->ls_debug_locks_dentry);
 653         if (ls->ls_debug_all_dentry)
 654                 debugfs_remove(ls->ls_debug_all_dentry);
 655 }
 656
 657 int dlm_create_debug_file(struct dlm_ls *ls)
 658 {
 659         char name[DLM_LOCKSPACE_LEN+8];
 660
 661         /* format 1 */
 662
 663         ls->ls_debug_rsb_dentry = debugfs_create_file(ls->ls_name,
 664                                                       S_IFREG | S_IRUGO,
 665                                                       dlm_root,
 666                                                       ls,
 667                                                       &format1_fops);
 668         if (!ls->ls_debug_rsb_dentry)
 669                 goto fail;
 670
 671         /* format 2 */
 672
 673         memset(name, 0, sizeof(name));
 674         snprintf(name, DLM_LOCKSPACE_LEN+8, "%s_locks", ls->ls_name);
 675
 676         ls->ls_debug_locks_dentry = debugfs_create_file(name,
 677                                                         S_IFREG | S_IRUGO,
 678                                                         dlm_root,
 679                                                         ls,
 680                                                         &format2_fops);
 681         if (!ls->ls_debug_locks_dentry)
 682                 goto fail;
 683
 684         /* format 3 */
 685
 686         memset(name, 0, sizeof(name));
 687         snprintf(name, DLM_LOCKSPACE_LEN+8, "%s_all", ls->ls_name);
 688
 689         ls->ls_debug_all_dentry = debugfs_create_file(name,
 690                                                       S_IFREG | S_IRUGO,
 691                                                       dlm_root,
 692                                                       ls,
 693                                                       &format3_fops);
 694         if (!ls->ls_debug_all_dentry)
 695                 goto fail;
 696
 697         memset(name, 0, sizeof(name));
 698         snprintf(name, DLM_LOCKSPACE_LEN+8, "%s_waiters", ls->ls_name);
 699
 700         ls->ls_debug_waiters_dentry = debugfs_create_file(name,
 701                                                           S_IFREG | S_IRUGO,
 702                                                           dlm_root,
 703                                                           ls,
 704                                                           &waiters_fops);
 705         if (!ls->ls_debug_waiters_dentry)
 706                 goto fail;
 707
 708         return 0;
 709
 710  fail:
 711         dlm_delete_debug_file(ls);
 712         return -ENOMEM;
 713 }
 714
 715 int __init dlm_register_debugfs(void)
 716 {
 717         mutex_init(&debug_buf_lock);
 718         dlm_root = debugfs_create_dir("dlm", NULL);
 719         return dlm_root ? 0 : -ENOMEM;
 720 }
 721
 722 void dlm_unregister_debugfs(void)
 723 {
 724         debugfs_remove(dlm_root);
 725 }
 726