lustre/ldlm/ldlm_resource.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2010, 2017, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  *
  31  * lustre/ldlm/ldlm_resource.c
  32  *
  33  * Author: Phil Schwan <phil@clusterfs.com>
  34  * Author: Peter Braam <braam@clusterfs.com>
  35  */
  36
  37 #define DEBUG_SUBSYSTEM S_LDLM
  38 #include <lustre_dlm.h>
  39 #include <lustre_fid.h>
  40 #include <obd_class.h>
  41 #include <libcfs/linux/linux-hash.h>
  42 #include "ldlm_internal.h"
  43
  44 struct kmem_cache *ldlm_resource_slab, *ldlm_lock_slab;
  45 struct kmem_cache *ldlm_interval_tree_slab;
  46 struct kmem_cache *ldlm_inodebits_slab;
  47
  48 int ldlm_srv_namespace_nr = 0;
  49 int ldlm_cli_namespace_nr = 0;
  50
  51 DEFINE_MUTEX(ldlm_srv_namespace_lock);
  52 LIST_HEAD(ldlm_srv_namespace_list);
  53
  54 DEFINE_MUTEX(ldlm_cli_namespace_lock);
  55 /* Client Namespaces that have active resources in them.
  56  * Once all resources go away, ldlm_poold moves such namespaces to the
  57  * inactive list */
  58 LIST_HEAD(ldlm_cli_active_namespace_list);
  59 /* Client namespaces that don't have any locks in them */
  60 LIST_HEAD(ldlm_cli_inactive_namespace_list);
  61
  62 static struct dentry *ldlm_debugfs_dir;
  63 static struct dentry *ldlm_ns_debugfs_dir;
  64 struct dentry *ldlm_svc_debugfs_dir;
  65
  66 /* during debug dump certain amount of granted locks for one resource to avoid
  67  * DDOS. */
  68 static unsigned int ldlm_dump_granted_max = 256;
  69
  70 static ssize_t ldebugfs_dump_ns_seq_write(struct file *file,
  71                                           const char __user *buffer,
  72                                           size_t count, loff_t *off)
  73 {
  74         ldlm_dump_all_namespaces(LDLM_NAMESPACE_SERVER, D_DLMTRACE);
  75         ldlm_dump_all_namespaces(LDLM_NAMESPACE_CLIENT, D_DLMTRACE);
  76         RETURN(count);
  77 }
  78
  79 LDEBUGFS_FOPS_WR_ONLY(ldlm, dump_ns);
  80
  81 static int ldlm_rw_uint_seq_show(struct seq_file *m, void *v)
  82 {
  83         seq_printf(m, "%u\n", *(unsigned int *)m->private);
  84         return 0;
  85 }
  86
  87 static ssize_t
  88 ldlm_rw_uint_seq_write(struct file *file, const char __user *buffer,
  89                        size_t count, loff_t *off)
  90 {
  91         struct seq_file *seq = file->private_data;
  92
  93         if (!count)
  94                 return 0;
  95
  96         return kstrtouint_from_user(buffer, count, 0,
  97                                     (unsigned int *)seq->private);
  98 }
  99
 100 LDEBUGFS_SEQ_FOPS(ldlm_rw_uint);
 101
 102 #ifdef HAVE_SERVER_SUPPORT
 103
 104 static int seq_watermark_show(struct seq_file *m, void *data)
 105 {
 106         seq_printf(m, "%llu\n", *(__u64 *)m->private);
 107         return 0;
 108 }
 109
 110 static ssize_t seq_watermark_write(struct file *file,
 111                                    const char __user *buffer, size_t count,
 112                                    loff_t *off)
 113 {
 114         struct seq_file *m = file->private_data;
 115         u64 value;
 116         __u64 watermark;
 117         __u64 *data = m->private;
 118         bool wm_low = (data == &ldlm_reclaim_threshold_mb) ? true : false;
 119         char kernbuf[22] = "";
 120         int rc;
 121
 122         if (count >= sizeof(kernbuf))
 123                 return -EINVAL;
 124
 125         if (copy_from_user(kernbuf, buffer, count))
 126                 return -EFAULT;
 127         kernbuf[count] = 0;
 128
 129         rc = sysfs_memparse(kernbuf, count, &value, "MiB");
 130         if (rc < 0) {
 131                 CERROR("Failed to set %s, rc = %d.\n",
 132                        wm_low ? "lock_reclaim_threshold_mb" : "lock_limit_mb",
 133                        rc);
 134                 return rc;
 135         } else if (value != 0 && value < (1 << 20)) {
 136                 CERROR("%s should be greater than 1MB.\n",
 137                        wm_low ? "lock_reclaim_threshold_mb" : "lock_limit_mb");
 138                 return -EINVAL;
 139         }
 140         watermark = value >> 20;
 141
 142         if (wm_low) {
 143                 if (ldlm_lock_limit_mb != 0 && watermark > ldlm_lock_limit_mb) {
 144                         CERROR("lock_reclaim_threshold_mb must be smaller than "
 145                                "lock_limit_mb.\n");
 146                         return -EINVAL;
 147                 }
 148
 149                 *data = watermark;
 150                 if (watermark != 0) {
 151                         watermark <<= 20;
 152                         do_div(watermark, sizeof(struct ldlm_lock));
 153                 }
 154                 ldlm_reclaim_threshold = watermark;
 155         } else {
 156                 if (ldlm_reclaim_threshold_mb != 0 &&
 157                     watermark < ldlm_reclaim_threshold_mb) {
 158                         CERROR("lock_limit_mb must be greater than "
 159                                "lock_reclaim_threshold_mb.\n");
 160                         return -EINVAL;
 161                 }
 162
 163                 *data = watermark;
 164                 if (watermark != 0) {
 165                         watermark <<= 20;
 166                         do_div(watermark, sizeof(struct ldlm_lock));
 167                 }
 168                 ldlm_lock_limit = watermark;
 169         }
 170
 171         return count;
 172 }
 173
 174 static int seq_watermark_open(struct inode *inode, struct file *file)
 175 {
 176         return single_open(file, seq_watermark_show, inode->i_private);
 177 }
 178
 179 static const struct file_operations ldlm_watermark_fops = {
 180         .owner          = THIS_MODULE,
 181         .open           = seq_watermark_open,
 182         .read           = seq_read,
 183         .write          = seq_watermark_write,
 184         .llseek         = seq_lseek,
 185         .release        = lprocfs_single_release,
 186 };
 187
 188 static int seq_granted_show(struct seq_file *m, void *data)
 189 {
 190         seq_printf(m, "%llu\n", percpu_counter_sum_positive(
 191                    (struct percpu_counter *)m->private));
 192         return 0;
 193 }
 194
 195 static int seq_granted_open(struct inode *inode, struct file *file)
 196 {
 197         return single_open(file, seq_granted_show, inode->i_private);
 198 }
 199
 200 static const struct file_operations ldlm_granted_fops = {
 201         .owner  = THIS_MODULE,
 202         .open   = seq_granted_open,
 203         .read   = seq_read,
 204         .llseek = seq_lseek,
 205         .release = seq_release,
 206 };
 207
 208 #endif /* HAVE_SERVER_SUPPORT */
 209
 210 static struct ldebugfs_vars ldlm_debugfs_list[] = {
 211         { .name =       "dump_namespaces",
 212           .fops =       &ldlm_dump_ns_fops,
 213           .proc_mode =  0222 },
 214         { .name =       "dump_granted_max",
 215           .fops =       &ldlm_rw_uint_fops,
 216           .data =       &ldlm_dump_granted_max },
 217 #ifdef HAVE_SERVER_SUPPORT
 218         { .name =       "lock_reclaim_threshold_mb",
 219           .fops =       &ldlm_watermark_fops,
 220           .data =       &ldlm_reclaim_threshold_mb },
 221         { .name =       "lock_limit_mb",
 222           .fops =       &ldlm_watermark_fops,
 223           .data =       &ldlm_lock_limit_mb },
 224         { .name =       "lock_granted_count",
 225           .fops =       &ldlm_granted_fops,
 226           .data =       &ldlm_granted_total },
 227 #endif
 228         { NULL }
 229 };
 230
 231 int ldlm_debugfs_setup(void)
 232 {
 233         ENTRY;
 234         ldlm_debugfs_dir = debugfs_create_dir(OBD_LDLM_DEVICENAME,
 235                                              debugfs_lustre_root);
 236         ldlm_ns_debugfs_dir = debugfs_create_dir("namespaces",
 237                                                  ldlm_debugfs_dir);
 238         ldlm_svc_debugfs_dir = debugfs_create_dir("services",
 239                                                   ldlm_debugfs_dir);
 240
 241         ldebugfs_add_vars(ldlm_debugfs_dir, ldlm_debugfs_list, NULL);
 242
 243         RETURN(0);
 244 }
 245
 246 void ldlm_debugfs_cleanup(void)
 247 {
 248         debugfs_remove_recursive(ldlm_debugfs_dir);
 249
 250         ldlm_svc_debugfs_dir = NULL;
 251         ldlm_ns_debugfs_dir = NULL;
 252         ldlm_debugfs_dir = NULL;
 253 }
 254
 255 static ssize_t resource_count_show(struct kobject *kobj, struct attribute *attr,
 256                                    char *buf)
 257 {
 258         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 259                                                  ns_kobj);
 260         __u64                   res = 0;
 261         int                     i;
 262
 263         /* result is not strictly consistant */
 264         for (i = 0; i < (1 << ns->ns_bucket_bits); i++)
 265                 res += atomic_read(&ns->ns_rs_buckets[i].nsb_count);
 266         return sprintf(buf, "%lld\n", res);
 267 }
 268 LUSTRE_RO_ATTR(resource_count);
 269
 270 static ssize_t lock_count_show(struct kobject *kobj, struct attribute *attr,
 271                                char *buf)
 272 {
 273         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 274                                                  ns_kobj);
 275         __u64                   locks;
 276
 277         locks = lprocfs_stats_collector(ns->ns_stats, LDLM_NSS_LOCKS,
 278                                         LPROCFS_FIELDS_FLAGS_SUM);
 279         return sprintf(buf, "%lld\n", locks);
 280 }
 281 LUSTRE_RO_ATTR(lock_count);
 282
 283 static ssize_t lock_unused_count_show(struct kobject *kobj,
 284                                       struct attribute *attr,
 285                                       char *buf)
 286 {
 287         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 288                                                  ns_kobj);
 289
 290         return sprintf(buf, "%d\n", ns->ns_nr_unused);
 291 }
 292 LUSTRE_RO_ATTR(lock_unused_count);
 293
 294 static ssize_t lru_size_show(struct kobject *kobj, struct attribute *attr,
 295                              char *buf)
 296 {
 297         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 298                                                  ns_kobj);
 299         __u32 *nr = &ns->ns_max_unused;
 300
 301         if (ns_connect_lru_resize(ns))
 302                 nr = &ns->ns_nr_unused;
 303         return sprintf(buf, "%u\n", *nr);
 304 }
 305
 306 static ssize_t lru_size_store(struct kobject *kobj, struct attribute *attr,
 307                               const char *buffer, size_t count)
 308 {
 309         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 310                                                  ns_kobj);
 311         unsigned long tmp;
 312         int lru_resize;
 313         int err;
 314
 315         if (strncmp(buffer, "clear", 5) == 0) {
 316                 CDEBUG(D_DLMTRACE,
 317                        "dropping all unused locks from namespace %s\n",
 318                        ldlm_ns_name(ns));
 319                 /* Try to cancel all @ns_nr_unused locks. */
 320                 ldlm_cancel_lru(ns, INT_MAX, 0, LDLM_LRU_FLAG_CLEANUP);
 321                 return count;
 322         }
 323
 324         err = kstrtoul(buffer, 10, &tmp);
 325         if (err != 0) {
 326                 CERROR("lru_size: invalid value written\n");
 327                 return -EINVAL;
 328         }
 329         lru_resize = (tmp == 0);
 330
 331         if (ns_connect_lru_resize(ns)) {
 332                 if (!lru_resize)
 333                         ns->ns_max_unused = (unsigned int)tmp;
 334
 335                 if (tmp > ns->ns_nr_unused)
 336                         tmp = ns->ns_nr_unused;
 337                 tmp = ns->ns_nr_unused - tmp;
 338
 339                 CDEBUG(D_DLMTRACE,
 340                        "changing namespace %s unused locks from %u to %u\n",
 341                        ldlm_ns_name(ns), ns->ns_nr_unused,
 342                        (unsigned int)tmp);
 343
 344                 if (!lru_resize) {
 345                         CDEBUG(D_DLMTRACE,
 346                                "disable lru_resize for namespace %s\n",
 347                                ldlm_ns_name(ns));
 348                         ns->ns_connect_flags &= ~OBD_CONNECT_LRU_RESIZE;
 349                 }
 350                 ldlm_cancel_lru(ns, tmp, LCF_ASYNC, 0);
 351         } else {
 352                 CDEBUG(D_DLMTRACE,
 353                        "changing namespace %s max_unused from %u to %u\n",
 354                        ldlm_ns_name(ns), ns->ns_max_unused,
 355                        (unsigned int)tmp);
 356
 357                 /* Make sure that LRU resize was originally supported before
 358                  * turning it on here.
 359                  */
 360                 if (lru_resize &&
 361                     (ns->ns_orig_connect_flags & OBD_CONNECT_LRU_RESIZE)) {
 362                         CDEBUG(D_DLMTRACE,
 363                                "enable lru_resize for namespace %s\n",
 364                                ldlm_ns_name(ns));
 365                         ns->ns_connect_flags |= OBD_CONNECT_LRU_RESIZE;
 366                 }
 367                 ns->ns_max_unused = (unsigned int)tmp;
 368                 ldlm_cancel_lru(ns, 0, LCF_ASYNC, 0);
 369         }
 370
 371         return count;
 372 }
 373 LUSTRE_RW_ATTR(lru_size);
 374
 375 static ssize_t lru_cancel_batch_show(struct kobject *kobj,
 376                                  struct attribute *attr, char *buf)
 377 {
 378         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 379                                                  ns_kobj);
 380
 381         return snprintf(buf, sizeof(buf) - 1, "%u\n", ns->ns_cancel_batch);
 382 }
 383
 384 static ssize_t lru_cancel_batch_store(struct kobject *kobj,
 385                                   struct attribute *attr,
 386                                   const char *buffer, size_t count)
 387 {
 388         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 389                                                  ns_kobj);
 390         unsigned long tmp;
 391
 392         if (kstrtoul(buffer, 10, &tmp))
 393                 return -EINVAL;
 394
 395         ns->ns_cancel_batch = (unsigned int)tmp;
 396
 397         return count;
 398 }
 399 LUSTRE_RW_ATTR(lru_cancel_batch);
 400
 401 static ssize_t ns_recalc_pct_show(struct kobject *kobj,
 402                                   struct attribute *attr, char *buf)
 403 {
 404         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 405                                                  ns_kobj);
 406
 407         return snprintf(buf, sizeof(buf) - 1, "%u\n", ns->ns_recalc_pct);
 408 }
 409
 410 static ssize_t ns_recalc_pct_store(struct kobject *kobj,
 411                                    struct attribute *attr,
 412                                    const char *buffer, size_t count)
 413 {
 414         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 415                                                  ns_kobj);
 416         unsigned long tmp;
 417
 418         if (kstrtoul(buffer, 10, &tmp))
 419                 return -EINVAL;
 420
 421         if (tmp > 100)
 422                 return -ERANGE;
 423
 424         ns->ns_recalc_pct = (unsigned int)tmp;
 425
 426         return count;
 427 }
 428 LUSTRE_RW_ATTR(ns_recalc_pct);
 429
 430 static ssize_t lru_max_age_show(struct kobject *kobj, struct attribute *attr,
 431                                 char *buf)
 432 {
 433         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 434                                                  ns_kobj);
 435
 436         return sprintf(buf, "%lld\n", ktime_to_ms(ns->ns_max_age));
 437 }
 438
 439 static ssize_t lru_max_age_store(struct kobject *kobj, struct attribute *attr,
 440                                  const char *buffer, size_t count)
 441 {
 442         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 443                                                  ns_kobj);
 444         int scale = NSEC_PER_MSEC;
 445         unsigned long long tmp;
 446         char *buf;
 447
 448         /* Did the user ask in seconds or milliseconds. Default is in ms */
 449         buf = strstr(buffer, "ms");
 450         if (!buf) {
 451                 buf = strchr(buffer, 's');
 452                 if (buf)
 453                         scale = NSEC_PER_SEC;
 454         }
 455
 456         if (buf)
 457                 *buf = '\0';
 458
 459         if (kstrtoull(buffer, 10, &tmp))
 460                 return -EINVAL;
 461
 462         ns->ns_max_age = ktime_set(0, tmp * scale);
 463
 464         return count;
 465 }
 466 LUSTRE_RW_ATTR(lru_max_age);
 467
 468 static ssize_t early_lock_cancel_show(struct kobject *kobj,
 469                                       struct attribute *attr,
 470                                       char *buf)
 471 {
 472         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 473                                                  ns_kobj);
 474
 475         return sprintf(buf, "%d\n", ns_connect_cancelset(ns));
 476 }
 477
 478 static ssize_t early_lock_cancel_store(struct kobject *kobj,
 479                                        struct attribute *attr,
 480                                        const char *buffer,
 481                                        size_t count)
 482 {
 483         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 484                                                  ns_kobj);
 485         unsigned long supp = -1;
 486         int rc;
 487
 488         rc = kstrtoul(buffer, 10, &supp);
 489         if (rc < 0)
 490                 return rc;
 491
 492         if (supp == 0)
 493                 ns->ns_connect_flags &= ~OBD_CONNECT_CANCELSET;
 494         else if (ns->ns_orig_connect_flags & OBD_CONNECT_CANCELSET)
 495                 ns->ns_connect_flags |= OBD_CONNECT_CANCELSET;
 496         return count;
 497 }
 498 LUSTRE_RW_ATTR(early_lock_cancel);
 499
 500 static ssize_t dirty_age_limit_show(struct kobject *kobj,
 501                                     struct attribute *attr, char *buf)
 502 {
 503         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 504                                                  ns_kobj);
 505
 506         return scnprintf(buf, PAGE_SIZE, "%llu\n",
 507                          ktime_divns(ns->ns_dirty_age_limit, NSEC_PER_SEC));
 508 }
 509
 510 static ssize_t dirty_age_limit_store(struct kobject *kobj,
 511                                      struct attribute *attr,
 512                                      const char *buffer, size_t count)
 513 {
 514         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 515                                                  ns_kobj);
 516         unsigned long long tmp;
 517
 518         if (kstrtoull(buffer, 10, &tmp))
 519                 return -EINVAL;
 520
 521         ns->ns_dirty_age_limit = ktime_set(tmp, 0);
 522
 523         return count;
 524 }
 525 LUSTRE_RW_ATTR(dirty_age_limit);
 526
 527 #ifdef HAVE_SERVER_SUPPORT
 528 static ssize_t ctime_age_limit_show(struct kobject *kobj,
 529                                     struct attribute *attr, char *buf)
 530 {
 531         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 532                                                  ns_kobj);
 533
 534         return scnprintf(buf, PAGE_SIZE, "%u\n", ns->ns_ctime_age_limit);
 535 }
 536
 537 static ssize_t ctime_age_limit_store(struct kobject *kobj,
 538                                      struct attribute *attr,
 539                                      const char *buffer, size_t count)
 540 {
 541         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 542                                                  ns_kobj);
 543         unsigned long tmp;
 544
 545         if (kstrtoul(buffer, 10, &tmp))
 546                 return -EINVAL;
 547
 548         ns->ns_ctime_age_limit = tmp;
 549
 550         return count;
 551 }
 552 LUSTRE_RW_ATTR(ctime_age_limit);
 553
 554 static ssize_t lock_timeouts_show(struct kobject *kobj, struct attribute *attr,
 555                                   char *buf)
 556 {
 557         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 558                                                  ns_kobj);
 559
 560         return sprintf(buf, "%d\n", ns->ns_timeouts);
 561 }
 562 LUSTRE_RO_ATTR(lock_timeouts);
 563
 564 static ssize_t max_nolock_bytes_show(struct kobject *kobj,
 565                                      struct attribute *attr, char *buf)
 566 {
 567         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 568                                                  ns_kobj);
 569
 570         return sprintf(buf, "%u\n", ns->ns_max_nolock_size);
 571 }
 572
 573 static ssize_t max_nolock_bytes_store(struct kobject *kobj,
 574                                       struct attribute *attr,
 575                                       const char *buffer, size_t count)
 576 {
 577         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 578                                                  ns_kobj);
 579         unsigned long tmp;
 580         int err;
 581
 582         err = kstrtoul(buffer, 10, &tmp);
 583         if (err != 0)
 584                 return -EINVAL;
 585
 586         ns->ns_max_nolock_size = tmp;
 587
 588         return count;
 589 }
 590 LUSTRE_RW_ATTR(max_nolock_bytes);
 591
 592 static ssize_t contention_seconds_show(struct kobject *kobj,
 593                                        struct attribute *attr, char *buf)
 594 {
 595         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 596                                                  ns_kobj);
 597
 598         return scnprintf(buf, PAGE_SIZE, "%d\n", ns->ns_contention_time);
 599 }
 600
 601 static ssize_t contention_seconds_store(struct kobject *kobj,
 602                                         struct attribute *attr,
 603                                         const char *buffer, size_t count)
 604 {
 605         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 606                                                  ns_kobj);
 607         unsigned int tmp;
 608
 609         if (kstrtouint(buffer, 10, &tmp))
 610                 return -EINVAL;
 611
 612         ns->ns_contention_time = tmp;
 613
 614         return count;
 615 }
 616 LUSTRE_RW_ATTR(contention_seconds);
 617
 618 static ssize_t contended_locks_show(struct kobject *kobj,
 619                                     struct attribute *attr, char *buf)
 620 {
 621         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 622                                                  ns_kobj);
 623
 624         return sprintf(buf, "%u\n", ns->ns_contended_locks);
 625 }
 626
 627 static ssize_t contended_locks_store(struct kobject *kobj,
 628                                      struct attribute *attr,
 629                                      const char *buffer, size_t count)
 630 {
 631         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 632                                                  ns_kobj);
 633         unsigned long tmp;
 634         int err;
 635
 636         err = kstrtoul(buffer, 10, &tmp);
 637         if (err != 0)
 638                 return -EINVAL;
 639
 640         ns->ns_contended_locks = tmp;
 641
 642         return count;
 643 }
 644 LUSTRE_RW_ATTR(contended_locks);
 645
 646 static ssize_t max_parallel_ast_show(struct kobject *kobj,
 647                                      struct attribute *attr, char *buf)
 648 {
 649         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 650                                                  ns_kobj);
 651
 652         return sprintf(buf, "%u\n", ns->ns_max_parallel_ast);
 653 }
 654
 655 static ssize_t max_parallel_ast_store(struct kobject *kobj,
 656                                       struct attribute *attr,
 657                                       const char *buffer, size_t count)
 658 {
 659         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 660                                                  ns_kobj);
 661         unsigned long tmp;
 662         int err;
 663
 664         err = kstrtoul(buffer, 10, &tmp);
 665         if (err != 0)
 666                 return -EINVAL;
 667
 668         ns->ns_max_parallel_ast = tmp;
 669
 670         return count;
 671 }
 672 LUSTRE_RW_ATTR(max_parallel_ast);
 673
 674 #endif /* HAVE_SERVER_SUPPORT */
 675
 676 /* These are for namespaces in /sys/fs/lustre/ldlm/namespaces/ */
 677 static struct attribute *ldlm_ns_attrs[] = {
 678         &lustre_attr_resource_count.attr,
 679         &lustre_attr_lock_count.attr,
 680         &lustre_attr_lock_unused_count.attr,
 681         &lustre_attr_ns_recalc_pct.attr,
 682         &lustre_attr_lru_size.attr,
 683         &lustre_attr_lru_cancel_batch.attr,
 684         &lustre_attr_lru_max_age.attr,
 685         &lustre_attr_early_lock_cancel.attr,
 686         &lustre_attr_dirty_age_limit.attr,
 687 #ifdef HAVE_SERVER_SUPPORT
 688         &lustre_attr_ctime_age_limit.attr,
 689         &lustre_attr_lock_timeouts.attr,
 690         &lustre_attr_max_nolock_bytes.attr,
 691         &lustre_attr_contention_seconds.attr,
 692         &lustre_attr_contended_locks.attr,
 693         &lustre_attr_max_parallel_ast.attr,
 694 #endif
 695         NULL,
 696 };
 697
 698 static void ldlm_ns_release(struct kobject *kobj)
 699 {
 700         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 701                                                  ns_kobj);
 702         complete(&ns->ns_kobj_unregister);
 703 }
 704
 705 KOBJ_ATTRIBUTE_GROUPS(ldlm_ns);
 706
 707 static struct kobj_type ldlm_ns_ktype = {
 708         .default_groups = KOBJ_ATTR_GROUPS(ldlm_ns),
 709         .sysfs_ops      = &lustre_sysfs_ops,
 710         .release        = ldlm_ns_release,
 711 };
 712
 713 static void ldlm_namespace_debugfs_unregister(struct ldlm_namespace *ns)
 714 {
 715         if (IS_ERR_OR_NULL(ns->ns_debugfs_entry))
 716                 CERROR("dlm namespace %s has no procfs dir?\n",
 717                        ldlm_ns_name(ns));
 718         else
 719                 debugfs_remove_recursive(ns->ns_debugfs_entry);
 720
 721         if (ns->ns_stats != NULL)
 722                 lprocfs_stats_free(&ns->ns_stats);
 723 }
 724
 725 void ldlm_namespace_sysfs_unregister(struct ldlm_namespace *ns)
 726 {
 727         kobject_put(&ns->ns_kobj);
 728         wait_for_completion(&ns->ns_kobj_unregister);
 729 }
 730
 731 int ldlm_namespace_sysfs_register(struct ldlm_namespace *ns)
 732 {
 733         int err;
 734
 735         ns->ns_kobj.kset = ldlm_ns_kset;
 736         init_completion(&ns->ns_kobj_unregister);
 737         err = kobject_init_and_add(&ns->ns_kobj, &ldlm_ns_ktype, NULL,
 738                                    "%s", ldlm_ns_name(ns));
 739
 740         ns->ns_stats = lprocfs_stats_alloc(LDLM_NSS_LAST, 0);
 741         if (!ns->ns_stats) {
 742                 kobject_put(&ns->ns_kobj);
 743                 return -ENOMEM;
 744         }
 745
 746         lprocfs_counter_init(ns->ns_stats, LDLM_NSS_LOCKS,
 747                              LPROCFS_CNTR_AVGMINMAX | LPROCFS_TYPE_LOCKS,
 748                              "locks");
 749
 750         return err;
 751 }
 752
 753 static int ldlm_namespace_debugfs_register(struct ldlm_namespace *ns)
 754 {
 755         struct dentry *ns_entry;
 756
 757         if (!IS_ERR_OR_NULL(ns->ns_debugfs_entry)) {
 758                 ns_entry = ns->ns_debugfs_entry;
 759         } else {
 760                 ns_entry = debugfs_create_dir(ldlm_ns_name(ns),
 761                                               ldlm_ns_debugfs_dir);
 762                 if (!ns_entry)
 763                         return -ENOMEM;
 764                 ns->ns_debugfs_entry = ns_entry;
 765         }
 766
 767         return 0;
 768 }
 769 #undef MAX_STRING_SIZE
 770
 771 static unsigned ldlm_res_hop_hash(struct cfs_hash *hs,
 772                                   const void *key, unsigned int mask)
 773 {
 774         const struct ldlm_res_id *id = key;
 775         unsigned int val = 0;
 776         unsigned int i;
 777
 778         for (i = 0; i < RES_NAME_SIZE; i++)
 779                 val += id->name[i];
 780         return val & mask;
 781 }
 782
 783 static unsigned int ldlm_res_hop_fid_hash(const struct ldlm_res_id *id, unsigned int bits)
 784 {
 785         struct lu_fid       fid;
 786         __u32               hash;
 787         __u32               val;
 788
 789         fid.f_seq = id->name[LUSTRE_RES_ID_SEQ_OFF];
 790         fid.f_oid = (__u32)id->name[LUSTRE_RES_ID_VER_OID_OFF];
 791         fid.f_ver = (__u32)(id->name[LUSTRE_RES_ID_VER_OID_OFF] >> 32);
 792
 793         hash = fid_flatten32(&fid);
 794         hash += (hash >> 4) + (hash << 12); /* mixing oid and seq */
 795         if (id->name[LUSTRE_RES_ID_HSH_OFF] != 0) {
 796                 val = id->name[LUSTRE_RES_ID_HSH_OFF];
 797         } else {
 798                 val = fid_oid(&fid);
 799         }
 800         hash += (val >> 5) + (val << 11);
 801         return cfs_hash_32(hash, bits);
 802 }
 803
 804 static void *ldlm_res_hop_key(struct hlist_node *hnode)
 805 {
 806         struct ldlm_resource   *res;
 807
 808         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 809         return &res->lr_name;
 810 }
 811
 812 static int ldlm_res_hop_keycmp(const void *key, struct hlist_node *hnode)
 813 {
 814         struct ldlm_resource   *res;
 815
 816         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 817         return ldlm_res_eq((const struct ldlm_res_id *)key,
 818                            (const struct ldlm_res_id *)&res->lr_name);
 819 }
 820
 821 static void *ldlm_res_hop_object(struct hlist_node *hnode)
 822 {
 823         return hlist_entry(hnode, struct ldlm_resource, lr_hash);
 824 }
 825
 826 static void
 827 ldlm_res_hop_get_locked(struct cfs_hash *hs, struct hlist_node *hnode)
 828 {
 829         struct ldlm_resource *res;
 830
 831         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 832         ldlm_resource_getref(res);
 833 }
 834
 835 static void ldlm_res_hop_put(struct cfs_hash *hs, struct hlist_node *hnode)
 836 {
 837         struct ldlm_resource *res;
 838
 839         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 840         ldlm_resource_putref(res);
 841 }
 842
 843 static struct cfs_hash_ops ldlm_ns_hash_ops = {
 844         .hs_hash        = ldlm_res_hop_hash,
 845         .hs_key         = ldlm_res_hop_key,
 846         .hs_keycmp      = ldlm_res_hop_keycmp,
 847         .hs_keycpy      = NULL,
 848         .hs_object      = ldlm_res_hop_object,
 849         .hs_get         = ldlm_res_hop_get_locked,
 850         .hs_put         = ldlm_res_hop_put
 851 };
 852
 853 static struct {
 854         /** hash bucket bits */
 855         unsigned                nsd_bkt_bits;
 856         /** hash bits */
 857         unsigned                nsd_all_bits;
 858 } ldlm_ns_hash_defs[] = {
 859         [LDLM_NS_TYPE_MDC] = {
 860                 .nsd_bkt_bits   = 11,
 861                 .nsd_all_bits   = 16,
 862         },
 863         [LDLM_NS_TYPE_MDT] = {
 864                 .nsd_bkt_bits   = 14,
 865                 .nsd_all_bits   = 21,
 866         },
 867         [LDLM_NS_TYPE_OSC] = {
 868                 .nsd_bkt_bits   = 8,
 869                 .nsd_all_bits   = 12,
 870         },
 871         [LDLM_NS_TYPE_OST] = {
 872                 .nsd_bkt_bits   = 11,
 873                 .nsd_all_bits   = 17,
 874         },
 875         [LDLM_NS_TYPE_MGC] = {
 876                 .nsd_bkt_bits   = 3,
 877                 .nsd_all_bits   = 4,
 878         },
 879         [LDLM_NS_TYPE_MGT] = {
 880                 .nsd_bkt_bits   = 3,
 881                 .nsd_all_bits   = 4,
 882         },
 883 };
 884
 885 /**
 886  * Create and initialize new empty namespace.
 887  */
 888 struct ldlm_namespace *ldlm_namespace_new(struct obd_device *obd, char *name,
 889                                           enum ldlm_side client,
 890                                           enum ldlm_appetite apt,
 891                                           enum ldlm_ns_type ns_type)
 892 {
 893         struct ldlm_namespace *ns = NULL;
 894         int idx;
 895         int rc;
 896
 897         ENTRY;
 898         LASSERT(obd != NULL);
 899
 900         rc = ldlm_get_ref();
 901         if (rc) {
 902                 CERROR("%s: ldlm_get_ref failed: rc = %d\n", name, rc);
 903                 RETURN(ERR_PTR(rc));
 904         }
 905
 906         if (ns_type >= ARRAY_SIZE(ldlm_ns_hash_defs) ||
 907             ldlm_ns_hash_defs[ns_type].nsd_bkt_bits == 0) {
 908                 rc = -EINVAL;
 909                 CERROR("%s: unknown namespace type %d: rc = %d\n",
 910                        name, ns_type, rc);
 911                 GOTO(out_ref, rc);
 912         }
 913
 914         OBD_ALLOC_PTR(ns);
 915         if (!ns)
 916                 GOTO(out_ref, rc = -ENOMEM);
 917
 918         ns->ns_rs_hash = cfs_hash_create(name,
 919                                          ldlm_ns_hash_defs[ns_type].nsd_all_bits,
 920                                          ldlm_ns_hash_defs[ns_type].nsd_all_bits,
 921                                          ldlm_ns_hash_defs[ns_type].nsd_bkt_bits,
 922                                          0,
 923                                          CFS_HASH_MIN_THETA,
 924                                          CFS_HASH_MAX_THETA,
 925                                          &ldlm_ns_hash_ops,
 926                                          CFS_HASH_DEPTH |
 927                                          CFS_HASH_BIGNAME |
 928                                          CFS_HASH_SPIN_BKTLOCK |
 929                                          CFS_HASH_NO_ITEMREF);
 930         if (!ns->ns_rs_hash)
 931                 GOTO(out_ns, rc = -ENOMEM);
 932
 933         ns->ns_bucket_bits = ldlm_ns_hash_defs[ns_type].nsd_all_bits -
 934                              ldlm_ns_hash_defs[ns_type].nsd_bkt_bits;
 935
 936         OBD_ALLOC_PTR_ARRAY_LARGE(ns->ns_rs_buckets, 1 << ns->ns_bucket_bits);
 937         if (!ns->ns_rs_buckets)
 938                 GOTO(out_hash, rc = -ENOMEM);
 939
 940         for (idx = 0; idx < (1 << ns->ns_bucket_bits); idx++) {
 941                 struct ldlm_ns_bucket *nsb = &ns->ns_rs_buckets[idx];
 942
 943                 at_init(&nsb->nsb_at_estimate, ldlm_enqueue_min, 0);
 944                 nsb->nsb_namespace = ns;
 945                 nsb->nsb_reclaim_start = 0;
 946                 atomic_set(&nsb->nsb_count, 0);
 947         }
 948
 949         ns->ns_obd = obd;
 950         ns->ns_appetite = apt;
 951         ns->ns_client = client;
 952         ns->ns_name = kstrdup(name, GFP_KERNEL);
 953         if (!ns->ns_name)
 954                 GOTO(out_hash, rc = -ENOMEM);
 955
 956         INIT_LIST_HEAD(&ns->ns_list_chain);
 957         INIT_LIST_HEAD(&ns->ns_unused_list);
 958         spin_lock_init(&ns->ns_lock);
 959         atomic_set(&ns->ns_bref, 0);
 960         init_waitqueue_head(&ns->ns_waitq);
 961
 962         ns->ns_max_nolock_size    = NS_DEFAULT_MAX_NOLOCK_BYTES;
 963         ns->ns_contention_time    = NS_DEFAULT_CONTENTION_SECONDS;
 964         ns->ns_contended_locks    = NS_DEFAULT_CONTENDED_LOCKS;
 965
 966         ns->ns_max_parallel_ast   = LDLM_DEFAULT_PARALLEL_AST_LIMIT;
 967         ns->ns_nr_unused          = 0;
 968         ns->ns_max_unused         = LDLM_DEFAULT_LRU_SIZE;
 969         ns->ns_cancel_batch       = LDLM_DEFAULT_LRU_SHRINK_BATCH;
 970         ns->ns_recalc_pct         = LDLM_DEFAULT_SLV_RECALC_PCT;
 971         ns->ns_max_age            = ktime_set(LDLM_DEFAULT_MAX_ALIVE, 0);
 972         ns->ns_ctime_age_limit    = LDLM_CTIME_AGE_LIMIT;
 973         ns->ns_dirty_age_limit    = ktime_set(LDLM_DIRTY_AGE_LIMIT, 0);
 974         ns->ns_timeouts           = 0;
 975         ns->ns_orig_connect_flags = 0;
 976         ns->ns_connect_flags      = 0;
 977         ns->ns_stopping           = 0;
 978         ns->ns_reclaim_start      = 0;
 979         ns->ns_last_pos           = &ns->ns_unused_list;
 980         ns->ns_flags              = 0;
 981
 982         rc = ldlm_namespace_sysfs_register(ns);
 983         if (rc) {
 984                 CERROR("%s: cannot initialize ns sysfs: rc = %d\n", name, rc);
 985                 GOTO(out_hash, rc);
 986         }
 987
 988         rc = ldlm_namespace_debugfs_register(ns);
 989         if (rc) {
 990                 CERROR("%s: cannot initialize ns proc: rc = %d\n", name, rc);
 991                 GOTO(out_sysfs, rc);
 992         }
 993
 994         idx = ldlm_namespace_nr_read(client);
 995         rc = ldlm_pool_init(&ns->ns_pool, ns, idx, client);
 996         if (rc) {
 997                 CERROR("%s: cannot initialize lock pool, rc = %d\n", name, rc);
 998                 GOTO(out_proc, rc);
 999         }
1000
1001         ldlm_namespace_register(ns, client);
1002         RETURN(ns);
1003 out_proc:
1004         ldlm_namespace_debugfs_unregister(ns);
1005 out_sysfs:
1006         ldlm_namespace_sysfs_unregister(ns);
1007         ldlm_namespace_cleanup(ns, 0);
1008 out_hash:
1009         OBD_FREE_PTR_ARRAY_LARGE(ns->ns_rs_buckets, 1 << ns->ns_bucket_bits);
1010         kfree(ns->ns_name);
1011         cfs_hash_putref(ns->ns_rs_hash);
1012 out_ns:
1013         OBD_FREE_PTR(ns);
1014 out_ref:
1015         ldlm_put_ref();
1016         RETURN(ERR_PTR(rc));
1017 }
1018 EXPORT_SYMBOL(ldlm_namespace_new);
1019
1020 /**
1021  * Cancel and destroy all locks on a resource.
1022  *
1023  * If flags contains FL_LOCAL_ONLY, don't try to tell the server, just
1024  * clean up.  This is currently only used for recovery, and we make
1025  * certain assumptions as a result--notably, that we shouldn't cancel
1026  * locks with refs.
1027  */
1028 static void cleanup_resource(struct ldlm_resource *res, struct list_head *q,
1029                              __u64 flags)
1030 {
1031         struct list_head *tmp;
1032         int rc = 0, client = ns_is_client(ldlm_res_to_ns(res));
1033         bool local_only = !!(flags & LDLM_FL_LOCAL_ONLY);
1034
1035         do {
1036                 struct ldlm_lock *lock = NULL;
1037
1038                 /* First, we look for non-cleaned-yet lock
1039                  * all cleaned locks are marked by CLEANED flag. */
1040                 lock_res(res);
1041                 list_for_each(tmp, q) {
1042                         lock = list_entry(tmp, struct ldlm_lock,
1043                                           l_res_link);
1044                         if (ldlm_is_cleaned(lock)) {
1045                                 lock = NULL;
1046                                 continue;
1047                         }
1048                         LDLM_LOCK_GET(lock);
1049                         ldlm_set_cleaned(lock);
1050                         break;
1051                 }
1052
1053                 if (lock == NULL) {
1054                         unlock_res(res);
1055                         break;
1056                 }
1057
1058                 /* Set CBPENDING so nothing in the cancellation path
1059                  * can match this lock. */
1060                 ldlm_set_cbpending(lock);
1061                 ldlm_set_failed(lock);
1062                 lock->l_flags |= flags;
1063
1064                 /* ... without sending a CANCEL message for local_only. */
1065                 if (local_only)
1066                         ldlm_set_local_only(lock);
1067
1068                 if (local_only && (lock->l_readers || lock->l_writers)) {
1069                         /*
1070                          * This is a little bit gross, but much better than the
1071                          * alternative: pretend that we got a blocking AST from
1072                          * the server, so that when the lock is decref'd, it
1073                          * will go away ...
1074                          */
1075                         unlock_res(res);
1076                         LDLM_DEBUG(lock, "setting FL_LOCAL_ONLY");
1077                         if (lock->l_flags & LDLM_FL_FAIL_LOC)
1078                                 schedule_timeout_uninterruptible(
1079                                         cfs_time_seconds(4));
1080
1081                         if (lock->l_completion_ast)
1082                                 lock->l_completion_ast(lock,
1083                                                        LDLM_FL_FAILED, NULL);
1084                         LDLM_LOCK_RELEASE(lock);
1085                         continue;
1086                 }
1087
1088                 if (client) {
1089                         struct lustre_handle lockh;
1090
1091                         unlock_res(res);
1092                         ldlm_lock2handle(lock, &lockh);
1093                         rc = ldlm_cli_cancel(&lockh, LCF_LOCAL);
1094                         if (rc)
1095                                 CERROR("ldlm_cli_cancel: %d\n", rc);
1096                 } else {
1097                         unlock_res(res);
1098                         LDLM_DEBUG(lock,
1099                                    "Freeing a lock still held by a client node");
1100                         ldlm_lock_cancel(lock);
1101                 }
1102                 LDLM_LOCK_RELEASE(lock);
1103         } while (1);
1104 }
1105
1106 static int ldlm_resource_clean(struct cfs_hash *hs, struct cfs_hash_bd *bd,
1107                                struct hlist_node *hnode, void *arg)
1108 {
1109         struct ldlm_resource *res = cfs_hash_object(hs, hnode);
1110         __u64 flags = *(__u64 *)arg;
1111
1112         cleanup_resource(res, &res->lr_granted, flags);
1113         cleanup_resource(res, &res->lr_waiting, flags);
1114
1115         return 0;
1116 }
1117
1118 static int ldlm_resource_complain(struct cfs_hash *hs, struct cfs_hash_bd *bd,
1119                                   struct hlist_node *hnode, void *arg)
1120 {
1121         struct ldlm_resource  *res = cfs_hash_object(hs, hnode);
1122
1123         lock_res(res);
1124         CERROR("%s: namespace resource "DLDLMRES" (%p) refcount nonzero "
1125                "(%d) after lock cleanup; forcing cleanup.\n",
1126                ldlm_ns_name(ldlm_res_to_ns(res)), PLDLMRES(res), res,
1127                atomic_read(&res->lr_refcount) - 1);
1128
1129         /* Use D_NETERROR since it is in the default mask */
1130         ldlm_resource_dump(D_NETERROR, res);
1131         unlock_res(res);
1132         return 0;
1133 }
1134
1135 /**
1136  * Cancel and destroy all locks in the namespace.
1137  *
1138  * Typically used during evictions when server notified client that it was
1139  * evicted and all of its state needs to be destroyed.
1140  * Also used during shutdown.
1141  */
1142 int ldlm_namespace_cleanup(struct ldlm_namespace *ns, __u64 flags)
1143 {
1144         if (ns == NULL) {
1145                 CDEBUG(D_INFO, "NULL ns, skipping cleanup\n");
1146                 return ELDLM_OK;
1147         }
1148
1149         cfs_hash_for_each_nolock(ns->ns_rs_hash, ldlm_resource_clean,
1150                                  &flags, 0);
1151         cfs_hash_for_each_nolock(ns->ns_rs_hash, ldlm_resource_complain,
1152                                  NULL, 0);
1153         return ELDLM_OK;
1154 }
1155 EXPORT_SYMBOL(ldlm_namespace_cleanup);
1156
1157 /**
1158  * Attempts to free namespace.
1159  *
1160  * Only used when namespace goes away, like during an unmount.
1161  */
1162 static int __ldlm_namespace_free(struct ldlm_namespace *ns, int force)
1163 {
1164         ENTRY;
1165
1166         /* At shutdown time, don't call the cancellation callback */
1167         ldlm_namespace_cleanup(ns, force ? LDLM_FL_LOCAL_ONLY : 0);
1168
1169         if (atomic_read(&ns->ns_bref) > 0) {
1170                 int rc;
1171                 CDEBUG(D_DLMTRACE,
1172                        "dlm namespace %s free waiting on refcount %d\n",
1173                        ldlm_ns_name(ns), atomic_read(&ns->ns_bref));
1174 force_wait:
1175                 if (force)
1176                         rc = wait_event_idle_timeout(
1177                                 ns->ns_waitq,
1178                                 atomic_read(&ns->ns_bref) == 0,
1179                                 cfs_time_seconds(1) / 4);
1180                 else
1181                         rc = l_wait_event_abortable(
1182                                 ns->ns_waitq, atomic_read(&ns->ns_bref) == 0);
1183
1184                 /* Forced cleanups should be able to reclaim all references,
1185                  * so it's safe to wait forever... we can't leak locks... */
1186                 if (force && rc == 0) {
1187                         rc = -ETIMEDOUT;
1188                         LCONSOLE_ERROR("Forced cleanup waiting for %s "
1189                                        "namespace with %d resources in use, "
1190                                        "(rc=%d)\n", ldlm_ns_name(ns),
1191                                        atomic_read(&ns->ns_bref), rc);
1192                         GOTO(force_wait, rc);
1193                 }
1194
1195                 if (atomic_read(&ns->ns_bref)) {
1196                         LCONSOLE_ERROR("Cleanup waiting for %s namespace "
1197                                        "with %d resources in use, (rc=%d)\n",
1198                                        ldlm_ns_name(ns),
1199                                        atomic_read(&ns->ns_bref), rc);
1200                         RETURN(ELDLM_NAMESPACE_EXISTS);
1201                 }
1202                 CDEBUG(D_DLMTRACE, "dlm namespace %s free done waiting\n",
1203                        ldlm_ns_name(ns));
1204         }
1205
1206         RETURN(ELDLM_OK);
1207 }
1208
1209 /**
1210  * Performs various cleanups for passed \a ns to make it drop refc and be
1211  * ready for freeing. Waits for refc == 0.
1212  *
1213  * The following is done:
1214  * (0) Unregister \a ns from its list to make inaccessible for potential
1215  * users like pools thread and others;
1216  * (1) Clear all locks in \a ns.
1217  */
1218 void ldlm_namespace_free_prior(struct ldlm_namespace *ns,
1219                                struct obd_import *imp,
1220                                int force)
1221 {
1222         int rc;
1223
1224         ENTRY;
1225         if (!ns) {
1226                 EXIT;
1227                 return;
1228         }
1229
1230         spin_lock(&ns->ns_lock);
1231         ns->ns_stopping = 1;
1232         spin_unlock(&ns->ns_lock);
1233
1234         /*
1235          * Can fail with -EINTR when force == 0 in which case try harder.
1236          */
1237         rc = __ldlm_namespace_free(ns, force);
1238         if (rc != ELDLM_OK) {
1239                 if (imp) {
1240                         ptlrpc_disconnect_import(imp, 0);
1241                         ptlrpc_invalidate_import(imp);
1242                 }
1243
1244                 /*
1245                  * With all requests dropped and the import inactive
1246                  * we are gaurenteed all reference will be dropped.
1247                  */
1248                 rc = __ldlm_namespace_free(ns, 1);
1249                 LASSERT(rc == 0);
1250         }
1251         EXIT;
1252 }
1253 EXPORT_SYMBOL(ldlm_namespace_free_prior);
1254
1255 /**
1256  * Performs freeing memory structures related to \a ns. This is only done
1257  * when ldlm_namespce_free_prior() successfully removed all resources
1258  * referencing \a ns and its refc == 0.
1259  */
1260 void ldlm_namespace_free_post(struct ldlm_namespace *ns)
1261 {
1262         ENTRY;
1263         if (!ns) {
1264                 EXIT;
1265                 return;
1266         }
1267
1268         /* Make sure that nobody can find this ns in its list. */
1269         ldlm_namespace_unregister(ns, ns->ns_client);
1270         /* Fini pool _before_ parent proc dir is removed. This is important as
1271          * ldlm_pool_fini() removes own proc dir which is child to @dir.
1272          * Removing it after @dir may cause oops. */
1273         ldlm_pool_fini(&ns->ns_pool);
1274
1275         ldlm_namespace_debugfs_unregister(ns);
1276         ldlm_namespace_sysfs_unregister(ns);
1277         cfs_hash_putref(ns->ns_rs_hash);
1278         OBD_FREE_PTR_ARRAY_LARGE(ns->ns_rs_buckets, 1 << ns->ns_bucket_bits);
1279         kfree(ns->ns_name);
1280         /* Namespace \a ns should be not on list at this time, otherwise
1281          * this will cause issues related to using freed \a ns in poold
1282          * thread.
1283          */
1284         LASSERT(list_empty(&ns->ns_list_chain));
1285         OBD_FREE_PTR(ns);
1286         ldlm_put_ref();
1287         EXIT;
1288 }
1289 EXPORT_SYMBOL(ldlm_namespace_free_post);
1290
1291 /**
1292  * Cleanup the resource, and free namespace.
1293  * bug 12864:
1294  * Deadlock issue:
1295  * proc1: destroy import
1296  *        class_disconnect_export(grab cl_sem) ->
1297  *              -> ldlm_namespace_free ->
1298  *              -> lprocfs_remove(grab _lprocfs_lock).
1299  * proc2: read proc info
1300  *        lprocfs_fops_read(grab _lprocfs_lock) ->
1301  *              -> osc_rd_active, etc(grab cl_sem).
1302  *
1303  * So that I have to split the ldlm_namespace_free into two parts - the first
1304  * part ldlm_namespace_free_prior is used to cleanup the resource which is
1305  * being used; the 2nd part ldlm_namespace_free_post is used to unregister the
1306  * lprocfs entries, and then free memory. It will be called w/o cli->cl_sem
1307  * held.
1308  */
1309 void ldlm_namespace_free(struct ldlm_namespace *ns,
1310                          struct obd_import *imp,
1311                          int force)
1312 {
1313         ldlm_namespace_free_prior(ns, imp, force);
1314         ldlm_namespace_free_post(ns);
1315 }
1316 EXPORT_SYMBOL(ldlm_namespace_free);
1317
1318 void ldlm_namespace_get(struct ldlm_namespace *ns)
1319 {
1320         atomic_inc(&ns->ns_bref);
1321 }
1322
1323 /* This is only for callers that care about refcount */
1324 static int ldlm_namespace_get_return(struct ldlm_namespace *ns)
1325 {
1326         return atomic_inc_return(&ns->ns_bref);
1327 }
1328
1329 void ldlm_namespace_put(struct ldlm_namespace *ns)
1330 {
1331         if (atomic_dec_and_lock(&ns->ns_bref, &ns->ns_lock)) {
1332                 wake_up(&ns->ns_waitq);
1333                 spin_unlock(&ns->ns_lock);
1334         }
1335 }
1336
1337 /** Register \a ns in the list of namespaces */
1338 void ldlm_namespace_register(struct ldlm_namespace *ns, enum ldlm_side client)
1339 {
1340         mutex_lock(ldlm_namespace_lock(client));
1341         LASSERT(list_empty(&ns->ns_list_chain));
1342         list_add(&ns->ns_list_chain, ldlm_namespace_inactive_list(client));
1343         ldlm_namespace_nr_inc(client);
1344         mutex_unlock(ldlm_namespace_lock(client));
1345 }
1346
1347 /** Unregister \a ns from the list of namespaces. */
1348 void ldlm_namespace_unregister(struct ldlm_namespace *ns, enum ldlm_side client)
1349 {
1350         mutex_lock(ldlm_namespace_lock(client));
1351         LASSERT(!list_empty(&ns->ns_list_chain));
1352         /* Some asserts and possibly other parts of the code are still
1353          * using list_empty(&ns->ns_list_chain). This is why it is
1354          * important to use list_del_init() here. */
1355         list_del_init(&ns->ns_list_chain);
1356         ldlm_namespace_nr_dec(client);
1357         mutex_unlock(ldlm_namespace_lock(client));
1358 }
1359
1360 /** Should be called with ldlm_namespace_lock(client) taken. */
1361 void ldlm_namespace_move_to_active_locked(struct ldlm_namespace *ns,
1362                                           enum ldlm_side client)
1363 {
1364         LASSERT(!list_empty(&ns->ns_list_chain));
1365         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
1366         list_move_tail(&ns->ns_list_chain, ldlm_namespace_list(client));
1367 }
1368
1369 /** Should be called with ldlm_namespace_lock(client) taken. */
1370 void ldlm_namespace_move_to_inactive_locked(struct ldlm_namespace *ns,
1371                                             enum ldlm_side client)
1372 {
1373         LASSERT(!list_empty(&ns->ns_list_chain));
1374         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
1375         list_move_tail(&ns->ns_list_chain,
1376                        ldlm_namespace_inactive_list(client));
1377 }
1378
1379 /** Should be called with ldlm_namespace_lock(client) taken. */
1380 struct ldlm_namespace *ldlm_namespace_first_locked(enum ldlm_side client)
1381 {
1382         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
1383         LASSERT(!list_empty(ldlm_namespace_list(client)));
1384         return container_of(ldlm_namespace_list(client)->next,
1385                             struct ldlm_namespace, ns_list_chain);
1386 }
1387
1388 static bool ldlm_resource_extent_new(struct ldlm_resource *res)
1389 {
1390         int idx;
1391
1392         OBD_SLAB_ALLOC(res->lr_itree, ldlm_interval_tree_slab,
1393                        sizeof(*res->lr_itree) * LCK_MODE_NUM);
1394         if (res->lr_itree == NULL)
1395                 return false;
1396         /* Initialize interval trees for each lock mode. */
1397         for (idx = 0; idx < LCK_MODE_NUM; idx++) {
1398                 res->lr_itree[idx].lit_size = 0;
1399                 res->lr_itree[idx].lit_mode = BIT(idx);
1400                 res->lr_itree[idx].lit_root = NULL;
1401         }
1402         return true;
1403 }
1404
1405 static bool ldlm_resource_inodebits_new(struct ldlm_resource *res)
1406 {
1407         int i;
1408
1409         OBD_ALLOC_PTR(res->lr_ibits_queues);
1410         if (res->lr_ibits_queues == NULL)
1411                 return false;
1412         for (i = 0; i < MDS_INODELOCK_NUMBITS; i++)
1413                 INIT_LIST_HEAD(&res->lr_ibits_queues->liq_waiting[i]);
1414         return true;
1415 }
1416
1417 static bool ldlm_resource_flock_new(struct ldlm_resource *res)
1418 {
1419         res->lr_flock_node.lfn_needs_reprocess = false;
1420         atomic_set(&res->lr_flock_node.lfn_unlock_pending, 0);
1421
1422         return true;
1423 }
1424
1425 /** Create and initialize new resource. */
1426 static struct ldlm_resource *ldlm_resource_new(enum ldlm_type ldlm_type)
1427 {
1428         struct ldlm_resource *res;
1429         bool rc;
1430
1431         OBD_SLAB_ALLOC_PTR_GFP(res, ldlm_resource_slab, GFP_NOFS);
1432         if (res == NULL)
1433                 return NULL;
1434
1435         switch (ldlm_type) {
1436         case LDLM_EXTENT:
1437                 rc = ldlm_resource_extent_new(res);
1438                 break;
1439         case LDLM_IBITS:
1440                 rc = ldlm_resource_inodebits_new(res);
1441                 break;
1442         case LDLM_FLOCK:
1443                 rc = ldlm_resource_flock_new(res);
1444                 break;
1445         default:
1446                 rc = true;
1447                 break;
1448         }
1449         if (!rc) {
1450                 OBD_SLAB_FREE_PTR(res, ldlm_resource_slab);
1451                 return NULL;
1452         }
1453
1454         INIT_LIST_HEAD(&res->lr_granted);
1455         INIT_LIST_HEAD(&res->lr_waiting);
1456
1457         atomic_set(&res->lr_refcount, 1);
1458         spin_lock_init(&res->lr_lock);
1459         lu_ref_init(&res->lr_reference);
1460
1461         /* Since LVB init can be delayed now, there is no longer need to
1462          * immediatelly acquire mutex here. */
1463         mutex_init(&res->lr_lvb_mutex);
1464         res->lr_lvb_initialized = false;
1465
1466         return res;
1467 }
1468
1469 static void __ldlm_resource_free(struct rcu_head *head)
1470 {
1471         struct ldlm_resource *res = container_of(head, struct ldlm_resource,
1472                                                  lr_rcu);
1473
1474         OBD_SLAB_FREE_PTR(res, ldlm_resource_slab);
1475 }
1476
1477 static void ldlm_resource_free(struct ldlm_resource *res)
1478 {
1479         if (res->lr_type == LDLM_EXTENT) {
1480                 if (res->lr_itree != NULL)
1481                         OBD_SLAB_FREE(res->lr_itree, ldlm_interval_tree_slab,
1482                                       sizeof(*res->lr_itree) * LCK_MODE_NUM);
1483         } else if (res->lr_type == LDLM_IBITS) {
1484                 if (res->lr_ibits_queues != NULL)
1485                         OBD_FREE_PTR(res->lr_ibits_queues);
1486         }
1487
1488         call_rcu(&res->lr_rcu, __ldlm_resource_free);
1489 }
1490
1491 /**
1492  * Return a reference to resource with given name, creating it if necessary.
1493  * Args: namespace with ns_lock unlocked
1494  * Locks: takes and releases NS hash-lock and res->lr_lock
1495  * Returns: referenced, unlocked ldlm_resource or ERR_PTR
1496  */
1497 struct ldlm_resource *
1498 ldlm_resource_get(struct ldlm_namespace *ns, const struct ldlm_res_id *name,
1499                   enum ldlm_type type, int create)
1500 {
1501         struct hlist_node       *hnode;
1502         struct ldlm_resource    *res = NULL;
1503         struct cfs_hash_bd              bd;
1504         __u64                   version;
1505         int                     ns_refcount = 0;
1506         int hash;
1507
1508         LASSERT(ns != NULL);
1509         LASSERT(ns->ns_rs_hash != NULL);
1510         LASSERT(name->name[0] != 0);
1511
1512         cfs_hash_bd_get_and_lock(ns->ns_rs_hash, (void *)name, &bd, 0);
1513         hnode = cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1514         if (hnode != NULL) {
1515                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1516                 GOTO(found, res);
1517         }
1518
1519         version = cfs_hash_bd_version_get(&bd);
1520         cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1521
1522         if (create == 0)
1523                 return ERR_PTR(-ENOENT);
1524
1525         LASSERTF(type >= LDLM_MIN_TYPE && type < LDLM_MAX_TYPE,
1526                  "type: %d\n", type);
1527         res = ldlm_resource_new(type);
1528         if (res == NULL)
1529                 return ERR_PTR(-ENOMEM);
1530
1531         hash = ldlm_res_hop_fid_hash(name, ns->ns_bucket_bits);
1532         res->lr_ns_bucket = &ns->ns_rs_buckets[hash];
1533         res->lr_name = *name;
1534         res->lr_type = type;
1535
1536         cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1);
1537         hnode = (version == cfs_hash_bd_version_get(&bd)) ? NULL :
1538                 cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1539
1540         if (hnode != NULL) {
1541                 /* Someone won the race and already added the resource. */
1542                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1543                 /* Clean lu_ref for failed resource. */
1544                 lu_ref_fini(&res->lr_reference);
1545                 ldlm_resource_free(res);
1546 found:
1547                 res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
1548                 return res;
1549         }
1550         /* We won! Let's add the resource. */
1551         cfs_hash_bd_add_locked(ns->ns_rs_hash, &bd, &res->lr_hash);
1552         if (atomic_inc_return(&res->lr_ns_bucket->nsb_count) == 1)
1553                 ns_refcount = ldlm_namespace_get_return(ns);
1554
1555         cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1556
1557         OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_CREATE_RESOURCE, 2);
1558
1559         /* Let's see if we happened to be the very first resource in this
1560          * namespace. If so, and this is a client namespace, we need to move
1561          * the namespace into the active namespaces list to be patrolled by
1562          * the ldlm_poold. */
1563         if (ns_is_client(ns) && ns_refcount == 1) {
1564                 mutex_lock(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
1565                 ldlm_namespace_move_to_active_locked(ns, LDLM_NAMESPACE_CLIENT);
1566                 mutex_unlock(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
1567         }
1568
1569         return res;
1570 }
1571 EXPORT_SYMBOL(ldlm_resource_get);
1572
1573 struct ldlm_resource *ldlm_resource_getref(struct ldlm_resource *res)
1574 {
1575         LASSERT(res != NULL);
1576         LASSERT(res != LP_POISON);
1577         atomic_inc(&res->lr_refcount);
1578         CDEBUG(D_INFO, "getref res: %p count: %d\n", res,
1579                atomic_read(&res->lr_refcount));
1580         return res;
1581 }
1582
1583 static void __ldlm_resource_putref_final(struct cfs_hash_bd *bd,
1584                                          struct ldlm_resource *res)
1585 {
1586         struct ldlm_ns_bucket *nsb = res->lr_ns_bucket;
1587
1588         if (!list_empty(&res->lr_granted)) {
1589                 ldlm_resource_dump(D_ERROR, res);
1590                 LBUG();
1591         }
1592
1593         if (!list_empty(&res->lr_waiting)) {
1594                 ldlm_resource_dump(D_ERROR, res);
1595                 LBUG();
1596         }
1597
1598         cfs_hash_bd_del_locked(nsb->nsb_namespace->ns_rs_hash,
1599                                bd, &res->lr_hash);
1600         lu_ref_fini(&res->lr_reference);
1601         if (atomic_dec_and_test(&nsb->nsb_count))
1602                 ldlm_namespace_put(nsb->nsb_namespace);
1603 }
1604
1605 /* Returns 1 if the resource was freed, 0 if it remains. */
1606 int ldlm_resource_putref(struct ldlm_resource *res)
1607 {
1608         struct ldlm_namespace *ns = ldlm_res_to_ns(res);
1609         struct cfs_hash_bd   bd;
1610
1611         LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON);
1612         CDEBUG(D_INFO, "putref res: %p count: %d\n",
1613                res, atomic_read(&res->lr_refcount) - 1);
1614
1615         cfs_hash_bd_get(ns->ns_rs_hash, &res->lr_name, &bd);
1616         if (cfs_hash_bd_dec_and_lock(ns->ns_rs_hash, &bd, &res->lr_refcount)) {
1617                 __ldlm_resource_putref_final(&bd, res);
1618                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1619                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
1620                         ns->ns_lvbo->lvbo_free(res);
1621                 ldlm_resource_free(res);
1622                 return 1;
1623         }
1624         return 0;
1625 }
1626 EXPORT_SYMBOL(ldlm_resource_putref);
1627
1628 static void __ldlm_resource_add_lock(struct ldlm_resource *res,
1629                                      struct list_head *head,
1630                                      struct ldlm_lock *lock,
1631                                      bool tail)
1632 {
1633         check_res_locked(res);
1634
1635         if (ldlm_is_destroyed(lock)) {
1636                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
1637                 return;
1638         }
1639
1640         LASSERT(list_empty(&lock->l_res_link));
1641
1642         if (tail)
1643                 list_add_tail(&lock->l_res_link, head);
1644         else
1645                 list_add(&lock->l_res_link, head);
1646
1647         if (res->lr_type == LDLM_IBITS)
1648                 ldlm_inodebits_add_lock(res, head, lock, tail);
1649
1650         ldlm_resource_dump(D_INFO, res);
1651 }
1652
1653 /**
1654  * Add a lock into a given resource into specified lock list.
1655  */
1656 void ldlm_resource_add_lock(struct ldlm_resource *res, struct list_head *head,
1657                             struct ldlm_lock *lock)
1658 {
1659         LDLM_DEBUG(lock, "About to add this lock");
1660
1661         __ldlm_resource_add_lock(res, head, lock, true);
1662 }
1663
1664 /**
1665  * Insert a lock into resource after specified lock.
1666  */
1667 void ldlm_resource_insert_lock_after(struct ldlm_lock *original,
1668                                      struct ldlm_lock *new)
1669 {
1670         LASSERT(!list_empty(&original->l_res_link));
1671
1672         LDLM_DEBUG(new, "About to insert this lock after %p: ", original);
1673         __ldlm_resource_add_lock(original->l_resource,
1674                                  &original->l_res_link,
1675                                  new, false);
1676 }
1677
1678 /**
1679  * Insert a lock into resource before the specified lock.
1680  *
1681  * IBITS waiting locks are to be inserted to the ibit lists as well, and only
1682  * the insert-after operation is supported for them, because the set of bits
1683  * of the previous and the new locks must match. Therefore, get the previous
1684  * lock and insert after.
1685  */
1686 void ldlm_resource_insert_lock_before(struct ldlm_lock *original,
1687                                       struct ldlm_lock *new)
1688 {
1689         LASSERT(!list_empty(&original->l_res_link));
1690
1691         LDLM_DEBUG(new, "About to insert this lock before %p: ", original);
1692         __ldlm_resource_add_lock(original->l_resource,
1693                                  original->l_res_link.prev, new, false);
1694 }
1695
1696 void ldlm_resource_unlink_lock(struct ldlm_lock *lock)
1697 {
1698         int type = lock->l_resource->lr_type;
1699
1700         check_res_locked(lock->l_resource);
1701         switch (type) {
1702         case LDLM_PLAIN:
1703                 ldlm_unlink_lock_skiplist(lock);
1704                 break;
1705         case LDLM_EXTENT:
1706                 ldlm_extent_unlink_lock(lock);
1707                 break;
1708         case LDLM_IBITS:
1709                 ldlm_inodebits_unlink_lock(lock);
1710                 break;
1711         }
1712         list_del_init(&lock->l_res_link);
1713 }
1714 EXPORT_SYMBOL(ldlm_resource_unlink_lock);
1715
1716 void ldlm_res2desc(struct ldlm_resource *res, struct ldlm_resource_desc *desc)
1717 {
1718         desc->lr_type = res->lr_type;
1719         desc->lr_name = res->lr_name;
1720 }
1721
1722 /**
1723  * Print information about all locks in all namespaces on this node to debug
1724  * log.
1725  */
1726 void ldlm_dump_all_namespaces(enum ldlm_side client, int level)
1727 {
1728         struct list_head *tmp;
1729
1730         if (!((libcfs_debug | D_ERROR) & level))
1731                 return;
1732
1733         mutex_lock(ldlm_namespace_lock(client));
1734
1735         list_for_each(tmp, ldlm_namespace_list(client)) {
1736                 struct ldlm_namespace *ns;
1737
1738                 ns = list_entry(tmp, struct ldlm_namespace, ns_list_chain);
1739                 ldlm_namespace_dump(level, ns);
1740         }
1741
1742         mutex_unlock(ldlm_namespace_lock(client));
1743 }
1744
1745 static int ldlm_res_hash_dump(struct cfs_hash *hs, struct cfs_hash_bd *bd,
1746                               struct hlist_node *hnode, void *arg)
1747 {
1748         struct ldlm_resource *res = cfs_hash_object(hs, hnode);
1749         int    level = (int)(unsigned long)arg;
1750
1751         lock_res(res);
1752         ldlm_resource_dump(level, res);
1753         unlock_res(res);
1754
1755         return 0;
1756 }
1757
1758 /**
1759  * Print information about all locks in this namespace on this node to debug
1760  * log.
1761  */
1762 void ldlm_namespace_dump(int level, struct ldlm_namespace *ns)
1763 {
1764         if (!((libcfs_debug | D_ERROR) & level))
1765                 return;
1766
1767         CDEBUG(level, "--- Namespace: %s (rc: %d, side: %s)\n",
1768                ldlm_ns_name(ns), atomic_read(&ns->ns_bref),
1769                ns_is_client(ns) ? "client" : "server");
1770
1771         if (ktime_get_seconds() < ns->ns_next_dump)
1772                 return;
1773
1774         cfs_hash_for_each_nolock(ns->ns_rs_hash,
1775                                  ldlm_res_hash_dump,
1776                                  (void *)(unsigned long)level, 0);
1777         spin_lock(&ns->ns_lock);
1778         ns->ns_next_dump = ktime_get_seconds() + 10;
1779         spin_unlock(&ns->ns_lock);
1780 }
1781
1782 /**
1783  * Print information about all locks in this resource to debug log.
1784  */
1785 void ldlm_resource_dump(int level, struct ldlm_resource *res)
1786 {
1787         struct ldlm_lock *lock;
1788         unsigned int granted = 0;
1789
1790         BUILD_BUG_ON(RES_NAME_SIZE != 4);
1791
1792         if (!((libcfs_debug | D_ERROR) & level))
1793                 return;
1794
1795         CDEBUG(level, "--- Resource: "DLDLMRES" (%p) refcount = %d\n",
1796                PLDLMRES(res), res, atomic_read(&res->lr_refcount));
1797
1798         if (!list_empty(&res->lr_granted)) {
1799                 CDEBUG(level, "Granted locks (in reverse order):\n");
1800                 list_for_each_entry_reverse(lock, &res->lr_granted,
1801                                                 l_res_link) {
1802                         LDLM_DEBUG_LIMIT(level, lock, "###");
1803                         if (!(level & D_CANTMASK) &&
1804                             ++granted > ldlm_dump_granted_max) {
1805                                 CDEBUG(level,
1806                                        "only dump %d granted locks to avoid DDOS.\n",
1807                                        granted);
1808                                 break;
1809                         }
1810                 }
1811         }
1812
1813         if (!list_empty(&res->lr_waiting)) {
1814                 CDEBUG(level, "Waiting locks:\n");
1815                 list_for_each_entry(lock, &res->lr_waiting, l_res_link)
1816                         LDLM_DEBUG_LIMIT(level, lock, "###");
1817         }
1818 }
1819 EXPORT_SYMBOL(ldlm_resource_dump);