module/zcommon/zfs_comutil.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  23  * Copyright (c) 2012 by Delphix. All rights reserved.
  24  */
  25
  26 /*
  27  * This file is intended for functions that ought to be common between user
  28  * land (libzfs) and the kernel. When many common routines need to be shared
  29  * then a separate file should to be created.
  30  */
  31
  32 #if defined(_KERNEL)
  33 #include <sys/systm.h>
  34 #else
  35 #include <string.h>
  36 #endif
  37
  38 #include <sys/types.h>
  39 #include <sys/fs/zfs.h>
  40 #include <sys/int_limits.h>
  41 #include <sys/nvpair.h>
  42 #include "zfs_comutil.h"
  43 #include <sys/zfs_ratelimit.h>
  44
  45 /*
  46  * Are there allocatable vdevs?
  47  */
  48 boolean_t
  49 zfs_allocatable_devs(nvlist_t *nv)
  50 {
  51         uint64_t is_log;
  52         uint_t c;
  53         nvlist_t **child;
  54         uint_t children;
  55
  56         if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
  57             &child, &children) != 0) {
  58                 return (B_FALSE);
  59         }
  60         for (c = 0; c < children; c++) {
  61                 is_log = 0;
  62                 (void) nvlist_lookup_uint64(child[c], ZPOOL_CONFIG_IS_LOG,
  63                     &is_log);
  64                 if (!is_log)
  65                         return (B_TRUE);
  66         }
  67         return (B_FALSE);
  68 }
  69
  70 void
  71 zpool_get_rewind_policy(nvlist_t *nvl, zpool_rewind_policy_t *zrpp)
  72 {
  73         nvlist_t *policy;
  74         nvpair_t *elem;
  75         char *nm;
  76
  77         /* Defaults */
  78         zrpp->zrp_request = ZPOOL_NO_REWIND;
  79         zrpp->zrp_maxmeta = 0;
  80         zrpp->zrp_maxdata = UINT64_MAX;
  81         zrpp->zrp_txg = UINT64_MAX;
  82
  83         if (nvl == NULL)
  84                 return;
  85
  86         elem = NULL;
  87         while ((elem = nvlist_next_nvpair(nvl, elem)) != NULL) {
  88                 nm = nvpair_name(elem);
  89                 if (strcmp(nm, ZPOOL_REWIND_POLICY) == 0) {
  90                         if (nvpair_value_nvlist(elem, &policy) == 0)
  91                                 zpool_get_rewind_policy(policy, zrpp);
  92                         return;
  93                 } else if (strcmp(nm, ZPOOL_REWIND_REQUEST) == 0) {
  94                         if (nvpair_value_uint32(elem, &zrpp->zrp_request) == 0)
  95                                 if (zrpp->zrp_request & ~ZPOOL_REWIND_POLICIES)
  96                                         zrpp->zrp_request = ZPOOL_NO_REWIND;
  97                 } else if (strcmp(nm, ZPOOL_REWIND_REQUEST_TXG) == 0) {
  98                         (void) nvpair_value_uint64(elem, &zrpp->zrp_txg);
  99                 } else if (strcmp(nm, ZPOOL_REWIND_META_THRESH) == 0) {
 100                         (void) nvpair_value_uint64(elem, &zrpp->zrp_maxmeta);
 101                 } else if (strcmp(nm, ZPOOL_REWIND_DATA_THRESH) == 0) {
 102                         (void) nvpair_value_uint64(elem, &zrpp->zrp_maxdata);
 103                 }
 104         }
 105         if (zrpp->zrp_request == 0)
 106                 zrpp->zrp_request = ZPOOL_NO_REWIND;
 107 }
 108
 109 typedef struct zfs_version_spa_map {
 110         int     version_zpl;
 111         int     version_spa;
 112 } zfs_version_spa_map_t;
 113
 114 /*
 115  * Keep this table in monotonically increasing version number order.
 116  */
 117 static zfs_version_spa_map_t zfs_version_table[] = {
 118         {ZPL_VERSION_INITIAL, SPA_VERSION_INITIAL},
 119         {ZPL_VERSION_DIRENT_TYPE, SPA_VERSION_INITIAL},
 120         {ZPL_VERSION_FUID, SPA_VERSION_FUID},
 121         {ZPL_VERSION_USERSPACE, SPA_VERSION_USERSPACE},
 122         {ZPL_VERSION_SA, SPA_VERSION_SA},
 123         {0, 0}
 124 };
 125
 126 /*
 127  * Return the max zpl version for a corresponding spa version
 128  * -1 is returned if no mapping exists.
 129  */
 130 int
 131 zfs_zpl_version_map(int spa_version)
 132 {
 133         int i;
 134         int version = -1;
 135
 136         for (i = 0; zfs_version_table[i].version_spa; i++) {
 137                 if (spa_version >= zfs_version_table[i].version_spa)
 138                         version = zfs_version_table[i].version_zpl;
 139         }
 140
 141         return (version);
 142 }
 143
 144 /*
 145  * Return the min spa version for a corresponding spa version
 146  * -1 is returned if no mapping exists.
 147  */
 148 int
 149 zfs_spa_version_map(int zpl_version)
 150 {
 151         int i;
 152         int version = -1;
 153
 154         for (i = 0; zfs_version_table[i].version_zpl; i++) {
 155                 if (zfs_version_table[i].version_zpl >= zpl_version)
 156                         return (zfs_version_table[i].version_spa);
 157         }
 158
 159         return (version);
 160 }
 161
 162 /*
 163  * This is the table of legacy internal event names; it should not be modified.
 164  * The internal events are now stored in the history log as strings.
 165  */
 166 const char *zfs_history_event_names[ZFS_NUM_LEGACY_HISTORY_EVENTS] = {
 167         "invalid event",
 168         "pool create",
 169         "vdev add",
 170         "pool remove",
 171         "pool destroy",
 172         "pool export",
 173         "pool import",
 174         "vdev attach",
 175         "vdev replace",
 176         "vdev detach",
 177         "vdev online",
 178         "vdev offline",
 179         "vdev upgrade",
 180         "pool clear",
 181         "pool scrub",
 182         "pool property set",
 183         "create",
 184         "clone",
 185         "destroy",
 186         "destroy_begin_sync",
 187         "inherit",
 188         "property set",
 189         "quota set",
 190         "permission update",
 191         "permission remove",
 192         "permission who remove",
 193         "promote",
 194         "receive",
 195         "rename",
 196         "reservation set",
 197         "replay_inc_sync",
 198         "replay_full_sync",
 199         "rollback",
 200         "snapshot",
 201         "filesystem version upgrade",
 202         "refquota set",
 203         "refreservation set",
 204         "pool scrub done",
 205         "user hold",
 206         "user release",
 207         "pool split",
 208 };
 209
 210 /*
 211  * Initialize rate limit struct
 212  *
 213  * rl:          zfs_ratelimit_t struct
 214  * burst:       Number to allow in an interval before rate limiting
 215  * interval:    Interval time in seconds
 216  */
 217 void
 218 zfs_ratelimit_init(zfs_ratelimit_t *rl, unsigned int *burst,
 219     unsigned int interval)
 220 {
 221         rl->count = 0;
 222         rl->start = 0;
 223         rl->interval = interval;
 224         rl->burst = burst;
 225         mutex_init(&rl->lock, NULL, MUTEX_DEFAULT, NULL);
 226 }
 227
 228 /*
 229  * Finalize rate limit struct
 230  *
 231  * rl:          zfs_ratelimit_t struct
 232  */
 233 void
 234 zfs_ratelimit_fini(zfs_ratelimit_t *rl)
 235 {
 236         mutex_destroy(&rl->lock);
 237 }
 238
 239 /*
 240  * Re-implementation of the kernel's __ratelimit() function
 241  *
 242  * We had to write our own rate limiter because the kernel's __ratelimit()
 243  * function annoyingly prints out how many times it rate limited to the kernel
 244  * logs (and there's no way to turn it off):
 245  *
 246  *      __ratelimit: 59 callbacks suppressed
 247  *
 248  * If the kernel ever allows us to disable these prints, we should go back to
 249  * using __ratelimit() instead.
 250  *
 251  * Return values are the same as __ratelimit():
 252  *
 253  * 0: If we're rate limiting
 254  * 1: If we're not rate limiting.
 255  */
 256 int
 257 zfs_ratelimit(zfs_ratelimit_t *rl)
 258 {
 259         hrtime_t now;
 260         hrtime_t elapsed;
 261         int rc = 1;
 262
 263         mutex_enter(&rl->lock);
 264
 265         now = gethrtime();
 266         elapsed = now - rl->start;
 267
 268         rl->count++;
 269         if (NSEC2SEC(elapsed) >= rl->interval) {
 270                 rl->start = now;
 271                 rl->count = 0;
 272         } else {
 273                 if (rl->count >= *rl->burst) {
 274                         rc = 0; /* We're ratelimiting */
 275                 }
 276         }
 277         mutex_exit(&rl->lock);
 278
 279         return (rc);
 280 }
 281
 282 #if defined(_KERNEL) && defined(HAVE_SPL)
 283 EXPORT_SYMBOL(zfs_allocatable_devs);
 284 EXPORT_SYMBOL(zpool_get_rewind_policy);
 285 EXPORT_SYMBOL(zfs_zpl_version_map);
 286 EXPORT_SYMBOL(zfs_spa_version_map);
 287 EXPORT_SYMBOL(zfs_history_event_names);
 288 EXPORT_SYMBOL(zfs_ratelimit_init);
 289 EXPORT_SYMBOL(zfs_ratelimit_fini);
 290 EXPORT_SYMBOL(zfs_ratelimit);
 291 #endif