module/spl/spl-kstat.c

   1 /*
   2  *  Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
   3  *  Copyright (C) 2007 The Regents of the University of California.
   4  *  Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
   5  *  Written by Brian Behlendorf <behlendorf1@llnl.gov>.
   6  *  UCRL-CODE-235197
   7  *
   8  *  This file is part of the SPL, Solaris Porting Layer.
   9  *  For details, see <http://zfsonlinux.org/>.
  10  *
  11  *  The SPL is free software; you can redistribute it and/or modify it
  12  *  under the terms of the GNU General Public License as published by the
  13  *  Free Software Foundation; either version 2 of the License, or (at your
  14  *  option) any later version.
  15  *
  16  *  The SPL is distributed in the hope that it will be useful, but WITHOUT
  17  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  18  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  19  *  for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License along
  22  *  with the SPL.  If not, see <http://www.gnu.org/licenses/>.
  23  *
  24  *  Solaris Porting Layer (SPL) Kstat Implementation.
  25  */
  26
  27 #include <linux/seq_file.h>
  28 #include <sys/kstat.h>
  29 #include <sys/vmem.h>
  30 #include <sys/cmn_err.h>
  31 #include <sys/sysmacros.h>
  32
  33 #ifndef HAVE_PDE_DATA
  34 #define PDE_DATA(x) (PDE(x)->data)
  35 #endif
  36
  37 static kmutex_t kstat_module_lock;
  38 static struct list_head kstat_module_list;
  39 static kid_t kstat_id;
  40
  41 static int
  42 kstat_resize_raw(kstat_t *ksp)
  43 {
  44         if (ksp->ks_raw_bufsize == KSTAT_RAW_MAX)
  45                 return (ENOMEM);
  46
  47         vmem_free(ksp->ks_raw_buf, ksp->ks_raw_bufsize);
  48         ksp->ks_raw_bufsize = MIN(ksp->ks_raw_bufsize * 2, KSTAT_RAW_MAX);
  49         ksp->ks_raw_buf = vmem_alloc(ksp->ks_raw_bufsize, KM_SLEEP);
  50
  51         return (0);
  52 }
  53
  54 void
  55 kstat_waitq_enter(kstat_io_t *kiop)
  56 {
  57         hrtime_t new, delta;
  58         ulong_t wcnt;
  59
  60         new = gethrtime();
  61         delta = new - kiop->wlastupdate;
  62         kiop->wlastupdate = new;
  63         wcnt = kiop->wcnt++;
  64         if (wcnt != 0) {
  65                 kiop->wlentime += delta * wcnt;
  66                 kiop->wtime += delta;
  67         }
  68 }
  69 EXPORT_SYMBOL(kstat_waitq_enter);
  70
  71 void
  72 kstat_waitq_exit(kstat_io_t *kiop)
  73 {
  74         hrtime_t new, delta;
  75         ulong_t wcnt;
  76
  77         new = gethrtime();
  78         delta = new - kiop->wlastupdate;
  79         kiop->wlastupdate = new;
  80         wcnt = kiop->wcnt--;
  81         ASSERT((int)wcnt > 0);
  82         kiop->wlentime += delta * wcnt;
  83         kiop->wtime += delta;
  84 }
  85 EXPORT_SYMBOL(kstat_waitq_exit);
  86
  87 void
  88 kstat_runq_enter(kstat_io_t *kiop)
  89 {
  90         hrtime_t new, delta;
  91         ulong_t rcnt;
  92
  93         new = gethrtime();
  94         delta = new - kiop->rlastupdate;
  95         kiop->rlastupdate = new;
  96         rcnt = kiop->rcnt++;
  97         if (rcnt != 0) {
  98                 kiop->rlentime += delta * rcnt;
  99                 kiop->rtime += delta;
 100         }
 101 }
 102 EXPORT_SYMBOL(kstat_runq_enter);
 103
 104 void
 105 kstat_runq_exit(kstat_io_t *kiop)
 106 {
 107         hrtime_t new, delta;
 108         ulong_t rcnt;
 109
 110         new = gethrtime();
 111         delta = new - kiop->rlastupdate;
 112         kiop->rlastupdate = new;
 113         rcnt = kiop->rcnt--;
 114         ASSERT((int)rcnt > 0);
 115         kiop->rlentime += delta * rcnt;
 116         kiop->rtime += delta;
 117 }
 118 EXPORT_SYMBOL(kstat_runq_exit);
 119
 120 static int
 121 kstat_seq_show_headers(struct seq_file *f)
 122 {
 123         kstat_t *ksp = (kstat_t *)f->private;
 124         int rc = 0;
 125
 126         ASSERT(ksp->ks_magic == KS_MAGIC);
 127
 128         seq_printf(f, "%d %d 0x%02x %d %d %lld %lld\n",
 129             ksp->ks_kid, ksp->ks_type, ksp->ks_flags,
 130             ksp->ks_ndata, (int)ksp->ks_data_size,
 131             ksp->ks_crtime, ksp->ks_snaptime);
 132
 133         switch (ksp->ks_type) {
 134                 case KSTAT_TYPE_RAW:
 135 restart:
 136                         if (ksp->ks_raw_ops.headers) {
 137                                 rc = ksp->ks_raw_ops.headers(
 138                                     ksp->ks_raw_buf, ksp->ks_raw_bufsize);
 139                                 if (rc == ENOMEM && !kstat_resize_raw(ksp))
 140                                         goto restart;
 141                                 if (!rc)
 142                                         seq_puts(f, ksp->ks_raw_buf);
 143                         } else {
 144                                 seq_printf(f, "raw data\n");
 145                         }
 146                         break;
 147                 case KSTAT_TYPE_NAMED:
 148                         seq_printf(f, "%-31s %-4s %s\n",
 149                             "name", "type", "data");
 150                         break;
 151                 case KSTAT_TYPE_INTR:
 152                         seq_printf(f, "%-8s %-8s %-8s %-8s %-8s\n",
 153                             "hard", "soft", "watchdog",
 154                             "spurious", "multsvc");
 155                         break;
 156                 case KSTAT_TYPE_IO:
 157                         seq_printf(f,
 158                             "%-8s %-8s %-8s %-8s %-8s %-8s "
 159                             "%-8s %-8s %-8s %-8s %-8s %-8s\n",
 160                             "nread", "nwritten", "reads", "writes",
 161                             "wtime", "wlentime", "wupdate",
 162                             "rtime", "rlentime", "rupdate",
 163                             "wcnt", "rcnt");
 164                         break;
 165                 case KSTAT_TYPE_TIMER:
 166                         seq_printf(f,
 167                             "%-31s %-8s "
 168                             "%-8s %-8s %-8s %-8s %-8s\n",
 169                             "name", "events", "elapsed",
 170                             "min", "max", "start", "stop");
 171                         break;
 172                 default:
 173                         PANIC("Undefined kstat type %d\n", ksp->ks_type);
 174         }
 175
 176         return (-rc);
 177 }
 178
 179 static int
 180 kstat_seq_show_raw(struct seq_file *f, unsigned char *p, int l)
 181 {
 182         int i, j;
 183
 184         for (i = 0; ; i++) {
 185                 seq_printf(f, "%03x:", i);
 186
 187                 for (j = 0; j < 16; j++) {
 188                         if (i * 16 + j >= l) {
 189                                 seq_printf(f, "\n");
 190                                 goto out;
 191                         }
 192
 193                         seq_printf(f, " %02x", (unsigned char)p[i * 16 + j]);
 194                 }
 195                 seq_printf(f, "\n");
 196         }
 197 out:
 198         return (0);
 199 }
 200
 201 static int
 202 kstat_seq_show_named(struct seq_file *f, kstat_named_t *knp)
 203 {
 204         seq_printf(f, "%-31s %-4d ", knp->name, knp->data_type);
 205
 206         switch (knp->data_type) {
 207                 case KSTAT_DATA_CHAR:
 208                         knp->value.c[15] = '\0'; /* NULL terminate */
 209                         seq_printf(f, "%-16s", knp->value.c);
 210                         break;
 211                 /*
 212                  * NOTE - We need to be more careful able what tokens are
 213                  * used for each arch, for now this is correct for x86_64.
 214                  */
 215                 case KSTAT_DATA_INT32:
 216                         seq_printf(f, "%d", knp->value.i32);
 217                         break;
 218                 case KSTAT_DATA_UINT32:
 219                         seq_printf(f, "%u", knp->value.ui32);
 220                         break;
 221                 case KSTAT_DATA_INT64:
 222                         seq_printf(f, "%lld", (signed long long)knp->value.i64);
 223                         break;
 224                 case KSTAT_DATA_UINT64:
 225                         seq_printf(f, "%llu",
 226                             (unsigned long long)knp->value.ui64);
 227                         break;
 228                 case KSTAT_DATA_LONG:
 229                         seq_printf(f, "%ld", knp->value.l);
 230                         break;
 231                 case KSTAT_DATA_ULONG:
 232                         seq_printf(f, "%lu", knp->value.ul);
 233                         break;
 234                 case KSTAT_DATA_STRING:
 235                         KSTAT_NAMED_STR_PTR(knp)
 236                                 [KSTAT_NAMED_STR_BUFLEN(knp)-1] = '\0';
 237                         seq_printf(f, "%s", KSTAT_NAMED_STR_PTR(knp));
 238                         break;
 239                 default:
 240                         PANIC("Undefined kstat data type %d\n", knp->data_type);
 241         }
 242
 243         seq_printf(f, "\n");
 244
 245         return (0);
 246 }
 247
 248 static int
 249 kstat_seq_show_intr(struct seq_file *f, kstat_intr_t *kip)
 250 {
 251         seq_printf(f, "%-8u %-8u %-8u %-8u %-8u\n",
 252             kip->intrs[KSTAT_INTR_HARD],
 253             kip->intrs[KSTAT_INTR_SOFT],
 254             kip->intrs[KSTAT_INTR_WATCHDOG],
 255             kip->intrs[KSTAT_INTR_SPURIOUS],
 256             kip->intrs[KSTAT_INTR_MULTSVC]);
 257
 258         return (0);
 259 }
 260
 261 static int
 262 kstat_seq_show_io(struct seq_file *f, kstat_io_t *kip)
 263 {
 264         seq_printf(f,
 265             "%-8llu %-8llu %-8u %-8u %-8lld %-8lld "
 266             "%-8lld %-8lld %-8lld %-8lld %-8u %-8u\n",
 267             kip->nread, kip->nwritten,
 268             kip->reads, kip->writes,
 269             kip->wtime, kip->wlentime, kip->wlastupdate,
 270             kip->rtime, kip->rlentime, kip->rlastupdate,
 271             kip->wcnt,  kip->rcnt);
 272
 273         return (0);
 274 }
 275
 276 static int
 277 kstat_seq_show_timer(struct seq_file *f, kstat_timer_t *ktp)
 278 {
 279         seq_printf(f,
 280             "%-31s %-8llu %-8lld %-8lld %-8lld %-8lld %-8lld\n",
 281             ktp->name, ktp->num_events, ktp->elapsed_time,
 282             ktp->min_time, ktp->max_time,
 283             ktp->start_time, ktp->stop_time);
 284
 285         return (0);
 286 }
 287
 288 static int
 289 kstat_seq_show(struct seq_file *f, void *p)
 290 {
 291         kstat_t *ksp = (kstat_t *)f->private;
 292         int rc = 0;
 293
 294         ASSERT(ksp->ks_magic == KS_MAGIC);
 295
 296         switch (ksp->ks_type) {
 297                 case KSTAT_TYPE_RAW:
 298 restart:
 299                         if (ksp->ks_raw_ops.data) {
 300                                 rc = ksp->ks_raw_ops.data(
 301                                     ksp->ks_raw_buf, ksp->ks_raw_bufsize, p);
 302                                 if (rc == ENOMEM && !kstat_resize_raw(ksp))
 303                                         goto restart;
 304                                 if (!rc)
 305                                         seq_puts(f, ksp->ks_raw_buf);
 306                         } else {
 307                                 ASSERT(ksp->ks_ndata == 1);
 308                                 rc = kstat_seq_show_raw(f, ksp->ks_data,
 309                                     ksp->ks_data_size);
 310                         }
 311                         break;
 312                 case KSTAT_TYPE_NAMED:
 313                         rc = kstat_seq_show_named(f, (kstat_named_t *)p);
 314                         break;
 315                 case KSTAT_TYPE_INTR:
 316                         rc = kstat_seq_show_intr(f, (kstat_intr_t *)p);
 317                         break;
 318                 case KSTAT_TYPE_IO:
 319                         rc = kstat_seq_show_io(f, (kstat_io_t *)p);
 320                         break;
 321                 case KSTAT_TYPE_TIMER:
 322                         rc = kstat_seq_show_timer(f, (kstat_timer_t *)p);
 323                         break;
 324                 default:
 325                         PANIC("Undefined kstat type %d\n", ksp->ks_type);
 326         }
 327
 328         return (-rc);
 329 }
 330
 331 static int
 332 kstat_default_update(kstat_t *ksp, int rw)
 333 {
 334         ASSERT(ksp != NULL);
 335
 336         if (rw == KSTAT_WRITE)
 337                 return (EACCES);
 338
 339         return (0);
 340 }
 341
 342 static void *
 343 kstat_seq_data_addr(kstat_t *ksp, loff_t n)
 344 {
 345         void *rc = NULL;
 346
 347         switch (ksp->ks_type) {
 348                 case KSTAT_TYPE_RAW:
 349                         if (ksp->ks_raw_ops.addr)
 350                                 rc = ksp->ks_raw_ops.addr(ksp, n);
 351                         else
 352                                 rc = ksp->ks_data;
 353                         break;
 354                 case KSTAT_TYPE_NAMED:
 355                         rc = ksp->ks_data + n * sizeof (kstat_named_t);
 356                         break;
 357                 case KSTAT_TYPE_INTR:
 358                         rc = ksp->ks_data + n * sizeof (kstat_intr_t);
 359                         break;
 360                 case KSTAT_TYPE_IO:
 361                         rc = ksp->ks_data + n * sizeof (kstat_io_t);
 362                         break;
 363                 case KSTAT_TYPE_TIMER:
 364                         rc = ksp->ks_data + n * sizeof (kstat_timer_t);
 365                         break;
 366                 default:
 367                         PANIC("Undefined kstat type %d\n", ksp->ks_type);
 368         }
 369
 370         return (rc);
 371 }
 372
 373 static void *
 374 kstat_seq_start(struct seq_file *f, loff_t *pos)
 375 {
 376         loff_t n = *pos;
 377         kstat_t *ksp = (kstat_t *)f->private;
 378         ASSERT(ksp->ks_magic == KS_MAGIC);
 379
 380         mutex_enter(ksp->ks_lock);
 381
 382         if (ksp->ks_type == KSTAT_TYPE_RAW) {
 383                 ksp->ks_raw_bufsize = PAGE_SIZE;
 384                 ksp->ks_raw_buf = vmem_alloc(ksp->ks_raw_bufsize, KM_SLEEP);
 385         }
 386
 387         /* Dynamically update kstat, on error existing kstats are used */
 388         (void) ksp->ks_update(ksp, KSTAT_READ);
 389
 390         ksp->ks_snaptime = gethrtime();
 391
 392         if (!(ksp->ks_flags & KSTAT_FLAG_NO_HEADERS) && !n &&
 393             kstat_seq_show_headers(f))
 394                 return (NULL);
 395
 396         if (n >= ksp->ks_ndata)
 397                 return (NULL);
 398
 399         return (kstat_seq_data_addr(ksp, n));
 400 }
 401
 402 static void *
 403 kstat_seq_next(struct seq_file *f, void *p, loff_t *pos)
 404 {
 405         kstat_t *ksp = (kstat_t *)f->private;
 406         ASSERT(ksp->ks_magic == KS_MAGIC);
 407
 408         ++*pos;
 409         if (*pos >= ksp->ks_ndata)
 410                 return (NULL);
 411
 412         return (kstat_seq_data_addr(ksp, *pos));
 413 }
 414
 415 static void
 416 kstat_seq_stop(struct seq_file *f, void *v)
 417 {
 418         kstat_t *ksp = (kstat_t *)f->private;
 419         ASSERT(ksp->ks_magic == KS_MAGIC);
 420
 421         if (ksp->ks_type == KSTAT_TYPE_RAW)
 422                 vmem_free(ksp->ks_raw_buf, ksp->ks_raw_bufsize);
 423
 424         mutex_exit(ksp->ks_lock);
 425 }
 426
 427 static struct seq_operations kstat_seq_ops = {
 428         .show  = kstat_seq_show,
 429         .start = kstat_seq_start,
 430         .next  = kstat_seq_next,
 431         .stop  = kstat_seq_stop,
 432 };
 433
 434 static kstat_module_t *
 435 kstat_find_module(char *name)
 436 {
 437         kstat_module_t *module;
 438
 439         list_for_each_entry(module, &kstat_module_list, ksm_module_list) {
 440                 if (strncmp(name, module->ksm_name, KSTAT_STRLEN) == 0)
 441                         return (module);
 442         }
 443
 444         return (NULL);
 445 }
 446
 447 static kstat_module_t *
 448 kstat_create_module(char *name)
 449 {
 450         kstat_module_t *module;
 451         struct proc_dir_entry *pde;
 452
 453         pde = proc_mkdir(name, proc_spl_kstat);
 454         if (pde == NULL)
 455                 return (NULL);
 456
 457         module = kmem_alloc(sizeof (kstat_module_t), KM_SLEEP);
 458         module->ksm_proc = pde;
 459         strlcpy(module->ksm_name, name, KSTAT_STRLEN+1);
 460         INIT_LIST_HEAD(&module->ksm_kstat_list);
 461         list_add_tail(&module->ksm_module_list, &kstat_module_list);
 462
 463         return (module);
 464
 465 }
 466
 467 static void
 468 kstat_delete_module(kstat_module_t *module)
 469 {
 470         ASSERT(list_empty(&module->ksm_kstat_list));
 471         remove_proc_entry(module->ksm_name, proc_spl_kstat);
 472         list_del(&module->ksm_module_list);
 473         kmem_free(module, sizeof (kstat_module_t));
 474 }
 475
 476 static int
 477 proc_kstat_open(struct inode *inode, struct file *filp)
 478 {
 479         struct seq_file *f;
 480         int rc;
 481
 482         rc = seq_open(filp, &kstat_seq_ops);
 483         if (rc)
 484                 return (rc);
 485
 486         f = filp->private_data;
 487         f->private = PDE_DATA(inode);
 488
 489         return (rc);
 490 }
 491
 492 static ssize_t
 493 proc_kstat_write(struct file *filp, const char __user *buf, size_t len,
 494     loff_t *ppos)
 495 {
 496         struct seq_file *f = filp->private_data;
 497         kstat_t *ksp = f->private;
 498         int rc;
 499
 500         ASSERT(ksp->ks_magic == KS_MAGIC);
 501
 502         mutex_enter(ksp->ks_lock);
 503         rc = ksp->ks_update(ksp, KSTAT_WRITE);
 504         mutex_exit(ksp->ks_lock);
 505
 506         if (rc)
 507                 return (-rc);
 508
 509         *ppos += len;
 510         return (len);
 511 }
 512
 513 static struct file_operations proc_kstat_operations = {
 514         .open           = proc_kstat_open,
 515         .write          = proc_kstat_write,
 516         .read           = seq_read,
 517         .llseek         = seq_lseek,
 518         .release        = seq_release,
 519 };
 520
 521 void
 522 __kstat_set_raw_ops(kstat_t *ksp,
 523     int (*headers)(char *buf, size_t size),
 524     int (*data)(char *buf, size_t size, void *data),
 525     void *(*addr)(kstat_t *ksp, loff_t index))
 526 {
 527         ksp->ks_raw_ops.headers = headers;
 528         ksp->ks_raw_ops.data    = data;
 529         ksp->ks_raw_ops.addr    = addr;
 530 }
 531 EXPORT_SYMBOL(__kstat_set_raw_ops);
 532
 533 void
 534 kstat_proc_entry_init(kstat_proc_entry_t *kpep, const char *module,
 535     const char *name)
 536 {
 537         kpep->kpe_owner = NULL;
 538         kpep->kpe_proc = NULL;
 539         INIT_LIST_HEAD(&kpep->kpe_list);
 540         strncpy(kpep->kpe_module, module, KSTAT_STRLEN);
 541         strncpy(kpep->kpe_name, name, KSTAT_STRLEN);
 542 }
 543 EXPORT_SYMBOL(kstat_proc_entry_init);
 544
 545 kstat_t *
 546 __kstat_create(const char *ks_module, int ks_instance, const char *ks_name,
 547     const char *ks_class, uchar_t ks_type, uint_t ks_ndata,
 548     uchar_t ks_flags)
 549 {
 550         kstat_t *ksp;
 551
 552         ASSERT(ks_module);
 553         ASSERT(ks_instance == 0);
 554         ASSERT(ks_name);
 555
 556         if ((ks_type == KSTAT_TYPE_INTR) || (ks_type == KSTAT_TYPE_IO))
 557                 ASSERT(ks_ndata == 1);
 558
 559         ksp = kmem_zalloc(sizeof (*ksp), KM_SLEEP);
 560         if (ksp == NULL)
 561                 return (ksp);
 562
 563         mutex_enter(&kstat_module_lock);
 564         ksp->ks_kid = kstat_id;
 565         kstat_id++;
 566         mutex_exit(&kstat_module_lock);
 567
 568         ksp->ks_magic = KS_MAGIC;
 569         mutex_init(&ksp->ks_private_lock, NULL, MUTEX_DEFAULT, NULL);
 570         ksp->ks_lock = &ksp->ks_private_lock;
 571
 572         ksp->ks_crtime = gethrtime();
 573         ksp->ks_snaptime = ksp->ks_crtime;
 574         ksp->ks_instance = ks_instance;
 575         strncpy(ksp->ks_class, ks_class, KSTAT_STRLEN);
 576         ksp->ks_type = ks_type;
 577         ksp->ks_flags = ks_flags;
 578         ksp->ks_update = kstat_default_update;
 579         ksp->ks_private = NULL;
 580         ksp->ks_raw_ops.headers = NULL;
 581         ksp->ks_raw_ops.data = NULL;
 582         ksp->ks_raw_ops.addr = NULL;
 583         ksp->ks_raw_buf = NULL;
 584         ksp->ks_raw_bufsize = 0;
 585         kstat_proc_entry_init(&ksp->ks_proc, ks_module, ks_name);
 586
 587         switch (ksp->ks_type) {
 588                 case KSTAT_TYPE_RAW:
 589                         ksp->ks_ndata = 1;
 590                         ksp->ks_data_size = ks_ndata;
 591                         break;
 592                 case KSTAT_TYPE_NAMED:
 593                         ksp->ks_ndata = ks_ndata;
 594                         ksp->ks_data_size = ks_ndata * sizeof (kstat_named_t);
 595                         break;
 596                 case KSTAT_TYPE_INTR:
 597                         ksp->ks_ndata = ks_ndata;
 598                         ksp->ks_data_size = ks_ndata * sizeof (kstat_intr_t);
 599                         break;
 600                 case KSTAT_TYPE_IO:
 601                         ksp->ks_ndata = ks_ndata;
 602                         ksp->ks_data_size = ks_ndata * sizeof (kstat_io_t);
 603                         break;
 604                 case KSTAT_TYPE_TIMER:
 605                         ksp->ks_ndata = ks_ndata;
 606                         ksp->ks_data_size = ks_ndata * sizeof (kstat_timer_t);
 607                         break;
 608                 default:
 609                         PANIC("Undefined kstat type %d\n", ksp->ks_type);
 610         }
 611
 612         if (ksp->ks_flags & KSTAT_FLAG_VIRTUAL) {
 613                 ksp->ks_data = NULL;
 614         } else {
 615                 ksp->ks_data = kmem_zalloc(ksp->ks_data_size, KM_SLEEP);
 616                 if (ksp->ks_data == NULL) {
 617                         kmem_free(ksp, sizeof (*ksp));
 618                         ksp = NULL;
 619                 }
 620         }
 621
 622         return (ksp);
 623 }
 624 EXPORT_SYMBOL(__kstat_create);
 625
 626 static int
 627 kstat_detect_collision(kstat_proc_entry_t *kpep)
 628 {
 629         kstat_module_t *module;
 630         kstat_proc_entry_t *tmp;
 631         char *parent;
 632         char *cp;
 633
 634         parent = kmem_asprintf("%s", kpep->kpe_module);
 635
 636         if ((cp = strrchr(parent, '/')) == NULL) {
 637                 strfree(parent);
 638                 return (0);
 639         }
 640
 641         cp[0] = '\0';
 642         if ((module = kstat_find_module(parent)) != NULL) {
 643                 list_for_each_entry(tmp, &module->ksm_kstat_list, kpe_list) {
 644                         if (strncmp(tmp->kpe_name, cp+1, KSTAT_STRLEN) == 0) {
 645                                 strfree(parent);
 646                                 return (EEXIST);
 647                         }
 648                 }
 649         }
 650
 651         strfree(parent);
 652         return (0);
 653 }
 654
 655 /*
 656  * Add a file to the proc filesystem under the kstat namespace (i.e.
 657  * /proc/spl/kstat/). The file need not necessarily be implemented as a
 658  * kstat.
 659  */
 660 void
 661 kstat_proc_entry_install(kstat_proc_entry_t *kpep,
 662     const struct file_operations *file_ops, void *data)
 663 {
 664         kstat_module_t *module;
 665         kstat_proc_entry_t *tmp;
 666
 667         ASSERT(kpep);
 668
 669         mutex_enter(&kstat_module_lock);
 670
 671         module = kstat_find_module(kpep->kpe_module);
 672         if (module == NULL) {
 673                 if (kstat_detect_collision(kpep) != 0) {
 674                         cmn_err(CE_WARN, "kstat_create('%s', '%s'): namespace" \
 675                             " collision", kpep->kpe_module, kpep->kpe_name);
 676                         goto out;
 677                 }
 678                 module = kstat_create_module(kpep->kpe_module);
 679                 if (module == NULL)
 680                         goto out;
 681         }
 682
 683         /*
 684          * Only one entry by this name per-module, on failure the module
 685          * shouldn't be deleted because we know it has at least one entry.
 686          */
 687         list_for_each_entry(tmp, &module->ksm_kstat_list, kpe_list) {
 688                 if (strncmp(tmp->kpe_name, kpep->kpe_name, KSTAT_STRLEN) == 0)
 689                         goto out;
 690         }
 691
 692         list_add_tail(&kpep->kpe_list, &module->ksm_kstat_list);
 693
 694         kpep->kpe_owner = module;
 695         kpep->kpe_proc = proc_create_data(kpep->kpe_name, 0644,
 696             module->ksm_proc, file_ops, data);
 697         if (kpep->kpe_proc == NULL) {
 698                 list_del_init(&kpep->kpe_list);
 699                 if (list_empty(&module->ksm_kstat_list))
 700                         kstat_delete_module(module);
 701         }
 702 out:
 703         mutex_exit(&kstat_module_lock);
 704
 705 }
 706 EXPORT_SYMBOL(kstat_proc_entry_install);
 707
 708 void
 709 __kstat_install(kstat_t *ksp)
 710 {
 711         ASSERT(ksp);
 712         kstat_proc_entry_install(&ksp->ks_proc, &proc_kstat_operations, ksp);
 713 }
 714 EXPORT_SYMBOL(__kstat_install);
 715
 716 void
 717 kstat_proc_entry_delete(kstat_proc_entry_t *kpep)
 718 {
 719         kstat_module_t *module = kpep->kpe_owner;
 720         if (kpep->kpe_proc)
 721                 remove_proc_entry(kpep->kpe_name, module->ksm_proc);
 722
 723         mutex_enter(&kstat_module_lock);
 724         list_del_init(&kpep->kpe_list);
 725
 726         /*
 727          * Remove top level module directory if it wasn't empty before, but now
 728          * is.
 729          */
 730         if (kpep->kpe_proc && list_empty(&module->ksm_kstat_list))
 731                 kstat_delete_module(module);
 732         mutex_exit(&kstat_module_lock);
 733
 734 }
 735 EXPORT_SYMBOL(kstat_proc_entry_delete);
 736
 737 void
 738 __kstat_delete(kstat_t *ksp)
 739 {
 740         kstat_proc_entry_delete(&ksp->ks_proc);
 741
 742         if (!(ksp->ks_flags & KSTAT_FLAG_VIRTUAL))
 743                 kmem_free(ksp->ks_data, ksp->ks_data_size);
 744
 745         ksp->ks_lock = NULL;
 746         mutex_destroy(&ksp->ks_private_lock);
 747         kmem_free(ksp, sizeof (*ksp));
 748 }
 749 EXPORT_SYMBOL(__kstat_delete);
 750
 751 int
 752 spl_kstat_init(void)
 753 {
 754         mutex_init(&kstat_module_lock, NULL, MUTEX_DEFAULT, NULL);
 755         INIT_LIST_HEAD(&kstat_module_list);
 756         kstat_id = 0;
 757         return (0);
 758 }
 759
 760 void
 761 spl_kstat_fini(void)
 762 {
 763         ASSERT(list_empty(&kstat_module_list));
 764         mutex_destroy(&kstat_module_lock);
 765 }