lustre/quota/qsd_lib.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, write to the
  18  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19  * Boston, MA 021110-1307, USA
  20  *
  21  * GPL HEADER END
  22  */
  23 /*
  24  * Copyright (c) 2012 Intel, Inc.
  25  * Use is subject to license terms.
  26  *
  27  * Author: Johann Lombardi <johann.lombardi@intel.com>
  28  * Author: Niu    Yawei    <yawei.niu@intel.com>
  29  */
  30
  31 /*
  32  * Quota Slave Driver (QSD) management.
  33  *
  34  * The quota slave feature is implemented under the form of a library called
  35  * QSD. Each OSD device should create a QSD instance via qsd_init() which will
  36  * be used to manage quota enforcement for this device. This implies:
  37  * - completing the reintegration procedure with the quota master (aka QMT, see
  38  *   qmt_dev.c) to retrieve the latest quota settings and space distribution.
  39  * - managing quota locks in order to be notified of configuration changes.
  40  * - acquiring space from the QMT when quota space for a given user/group is
  41  *   close to exhaustion.
  42  * - allocating quota space to service threads for local request processing.
  43  *
  44  * Once the QSD instance created, the OSD device should invoke qsd_start()
  45  * when recovery is completed. This notifies the QSD that we are about to
  46  * process new requests on which quota should be strictly enforced.
  47  * Then, qsd_op_begin/end can be used to reserve/release/pre-acquire quota space
  48  * for/after each operation until shutdown where the QSD instance should be
  49  * freed via qsd_fini().
  50  */
  51
  52 #ifndef EXPORT_SYMTAB
  53 # define EXPORT_SYMTAB
  54 #endif
  55
  56 #define DEBUG_SUBSYSTEM S_LQUOTA
  57
  58 #include <obd_class.h>
  59 #include "qsd_internal.h"
  60
  61 cfs_mem_cache_t *upd_kmem;
  62
  63 struct lu_kmem_descr qsd_caches[] = {
  64         {
  65                 .ckd_cache = &upd_kmem,
  66                 .ckd_name  = "upd_kmem",
  67                 .ckd_size  = sizeof(struct qsd_upd_rec)
  68         },
  69         {
  70                 .ckd_cache = NULL
  71         }
  72 };
  73
  74 /* define qsd thread key */
  75 LU_KEY_INIT_FINI(qsd, struct qsd_thread_info);
  76 LU_CONTEXT_KEY_DEFINE(qsd, LCT_MD_THREAD | LCT_DT_THREAD | LCT_LOCAL);
  77 LU_KEY_INIT_GENERIC(qsd);
  78
  79 /* some procfs helpers */
  80 static int lprocfs_qsd_rd_state(char *page, char **start, off_t off,
  81                                 int count, int *eof, void *data)
  82 {
  83         struct qsd_instance     *qsd = (struct qsd_instance *)data;
  84         char                     enabled[5];
  85         int                      rc;
  86
  87         LASSERT(qsd != NULL);
  88
  89         memset(enabled, 0, sizeof(enabled));
  90         if (qsd_type_enabled(qsd, USRQUOTA))
  91                 strcat(enabled, "u");
  92         if (qsd_type_enabled(qsd, GRPQUOTA))
  93                 strcat(enabled, "g");
  94         if (strlen(enabled) == 0)
  95                 strcat(enabled, "none");
  96
  97         rc = snprintf(page, count,
  98                       "target name:    %s\n"
  99                       "pool ID:        %d\n"
 100                       "type:           %s\n"
 101                       "quota enabled:  %s\n"
 102                       "conn to master: %s\n",
 103                       qsd->qsd_svname, qsd->qsd_pool_id,
 104                       qsd->qsd_is_md ? "md" : "dt", enabled,
 105                       qsd->qsd_exp_valid ? "setup" : "not setup yet");
 106
 107         if (qsd->qsd_prepared)
 108                 rc +=  snprintf(page + rc, count - rc,
 109                                 "user uptodate:  glb[%d],slv[%d],reint[%d]\n"
 110                                 "group uptodate: glb[%d],slv[%d],reint[%d]\n",
 111                                 qsd->qsd_type_array[USRQUOTA]->qqi_glb_uptodate,
 112                                 qsd->qsd_type_array[USRQUOTA]->qqi_slv_uptodate,
 113                                 qsd->qsd_type_array[USRQUOTA]->qqi_reint,
 114                                 qsd->qsd_type_array[GRPQUOTA]->qqi_glb_uptodate,
 115                                 qsd->qsd_type_array[GRPQUOTA]->qqi_slv_uptodate,
 116                                 qsd->qsd_type_array[GRPQUOTA]->qqi_reint);
 117         return rc;
 118 }
 119
 120 static int lprocfs_qsd_rd_enabled(char *page, char **start, off_t off,
 121                                   int count, int *eof, void *data)
 122 {
 123         struct qsd_instance     *qsd = (struct qsd_instance *)data;
 124         char                     enabled[5];
 125
 126         LASSERT(qsd != NULL);
 127
 128         memset(enabled, 0, sizeof(enabled));
 129         if (qsd_type_enabled(qsd, USRQUOTA))
 130                 strcat(enabled, "u");
 131         if (qsd_type_enabled(qsd, GRPQUOTA))
 132                 strcat(enabled, "g");
 133         if (strlen(enabled) == 0)
 134                 strcat(enabled, "none");
 135
 136         return snprintf(page, count, "%s\n", enabled);
 137 }
 138
 139 /* force reintegration procedure to be executed.
 140  * Used for test/debugging purpose */
 141 static int lprocfs_qsd_wr_force_reint(struct file *file, const char *buffer,
 142                                       unsigned long count, void *data)
 143 {
 144         struct qsd_instance     *qsd = (struct qsd_instance *)data;
 145         int                      rc = 0, qtype;
 146
 147         LASSERT(qsd != NULL);
 148
 149         cfs_write_lock(&qsd->qsd_lock);
 150         if (qsd->qsd_stopping) {
 151                 /* don't mess up with shutdown procedure, it is already
 152                  * complicated enough */
 153                 rc = -ESHUTDOWN;
 154         } else if (!qsd->qsd_prepared) {
 155                 rc = -EAGAIN;
 156         } else {
 157                 /* mark all indexes as stale */
 158                 for (qtype = USRQUOTA; qtype < MAXQUOTAS; qtype++) {
 159                         qsd->qsd_type_array[qtype]->qqi_glb_uptodate = false;
 160                         qsd->qsd_type_array[qtype]->qqi_slv_uptodate = false;
 161                 }
 162         }
 163         cfs_write_unlock(&qsd->qsd_lock);
 164
 165         if (rc)
 166                 return rc;
 167
 168         /* kick off reintegration */
 169         for (qtype = USRQUOTA; qtype < MAXQUOTAS; qtype++) {
 170                 rc = qsd_start_reint_thread(qsd->qsd_type_array[qtype]);
 171                 if (rc)
 172                         break;
 173         }
 174         return rc == 0 ? count : rc;
 175 }
 176
 177 static int lprocfs_qsd_rd_timeout(char *page, char **start, off_t off,
 178                                   int count, int *eof, void *data)
 179 {
 180         struct qsd_instance     *qsd = (struct qsd_instance *)data;
 181         LASSERT(qsd != NULL);
 182
 183         return snprintf(page, count, "%d\n", qsd_wait_timeout(qsd));
 184 }
 185
 186 static int lprocfs_qsd_wr_timeout(struct file *file, const char *buffer,
 187                                   unsigned long count, void *data)
 188 {
 189         struct qsd_instance     *qsd = (struct qsd_instance *)data;
 190         int                      timeout, rc;
 191         LASSERT(qsd != NULL);
 192
 193         rc = lprocfs_write_helper(buffer, count, &timeout);
 194         if (rc)
 195                 return rc;
 196         if (timeout < 0)
 197                 return -EINVAL;
 198
 199         qsd->qsd_timeout = timeout;
 200         return count;
 201 }
 202
 203 static struct lprocfs_vars lprocfs_quota_qsd_vars[] = {
 204         { "info", lprocfs_qsd_rd_state, 0, 0},
 205         { "enabled", lprocfs_qsd_rd_enabled, 0, 0},
 206         { "force_reint", 0, lprocfs_qsd_wr_force_reint, 0},
 207         { "timeout", lprocfs_qsd_rd_timeout, lprocfs_qsd_wr_timeout, 0},
 208         { NULL }
 209 };
 210
 211 /*
 212  * Callback function invoked by the OSP layer when the connection to the master
 213  * has been set up.
 214  *
 215  * \param data - is a pointer to the qsd_instance
 216  *
 217  * \retval - 0 on success, appropriate error on failure
 218  */
 219 static int qsd_conn_callback(void *data)
 220 {
 221         struct qsd_instance *qsd = (struct qsd_instance *)data;
 222         int                  type;
 223         ENTRY;
 224
 225         /* qsd_exp should now be valid */
 226         LASSERT(qsd->qsd_exp);
 227
 228         /* grab reference on namespace */
 229         ldlm_namespace_get(class_exp2obd(qsd->qsd_exp)->obd_namespace);
 230         qsd->qsd_ns = class_exp2obd(qsd->qsd_exp)->obd_namespace;
 231
 232         cfs_write_lock(&qsd->qsd_lock);
 233         /* notify that qsd_exp is now valid */
 234         qsd->qsd_exp_valid = true;
 235         cfs_write_unlock(&qsd->qsd_lock);
 236
 237         /* Now that the connection to master is setup, we can initiate the
 238          * reintegration procedure for quota types which are enabled.
 239          * It is worth noting that, if the qsd_instance hasn't been started
 240          * already, then we can only complete the first two steps of the
 241          * reintegration procedure (i.e. global lock enqueue and slave
 242          * index transfer) since the space usage reconciliation (i.e.
 243          * step 3) will have to wait for qsd_start() to be called */
 244         for (type = USRQUOTA; type < MAXQUOTAS; type++) {
 245                 struct qsd_qtype_info *qqi = qsd->qsd_type_array[type];
 246                 cfs_waitq_signal(&qqi->qqi_reint_thread.t_ctl_waitq);
 247         }
 248
 249         RETURN(0);
 250 }
 251
 252 /*
 253  * Release qsd_qtype_info structure which contains data associated with a
 254  * given quota type. This releases the accounting objects.
 255  * It's called on OSD cleanup when the qsd instance is released.
 256  *
 257  * \param env - is the environment passed by the caller
 258  * \param qsd - is the qsd instance managing the qsd_qtype_info structure
 259  *              to be released
 260  * \param qtype - is the quota type to be shutdown
 261  */
 262 static void qsd_qtype_fini(const struct lu_env *env, struct qsd_instance *qsd,
 263                            int qtype)
 264 {
 265         struct qsd_qtype_info   *qqi;
 266         ENTRY;
 267
 268         if (qsd->qsd_type_array[qtype] == NULL)
 269                 RETURN_EXIT;
 270         qqi = qsd->qsd_type_array[qtype];
 271         qsd->qsd_type_array[qtype] = NULL;
 272
 273         /* all deferred work lists should be empty */
 274         LASSERT(cfs_list_empty(&qqi->qqi_deferred_glb));
 275         LASSERT(cfs_list_empty(&qqi->qqi_deferred_slv));
 276
 277         /* shutdown lquota site */
 278         if (qqi->qqi_site != NULL && !IS_ERR(qqi->qqi_site)) {
 279                 lquota_site_free(env, qqi->qqi_site);
 280                 qqi->qqi_site = NULL;
 281         }
 282
 283         /* by now, all qqi users should have gone away */
 284         LASSERT(cfs_atomic_read(&qqi->qqi_ref) == 1);
 285         lu_ref_fini(&qqi->qqi_reference);
 286
 287         /* release accounting object */
 288         if (qqi->qqi_acct_obj != NULL && !IS_ERR(qqi->qqi_acct_obj)) {
 289                 lu_object_put(env, &qqi->qqi_acct_obj->do_lu);
 290                 qqi->qqi_acct_obj = NULL;
 291         }
 292
 293         /* release slv index */
 294         if (qqi->qqi_slv_obj != NULL && !IS_ERR(qqi->qqi_slv_obj)) {
 295                 lu_object_put(env, &qqi->qqi_slv_obj->do_lu);
 296                 qqi->qqi_slv_obj = NULL;
 297                 qqi->qqi_slv_ver = 0;
 298         }
 299
 300         /* release global index */
 301         if (qqi->qqi_glb_obj != NULL && !IS_ERR(qqi->qqi_glb_obj)) {
 302                 lu_object_put(env, &qqi->qqi_glb_obj->do_lu);
 303                 qqi->qqi_glb_obj = NULL;
 304                 qqi->qqi_glb_ver = 0;
 305         }
 306
 307         OBD_FREE_PTR(qqi);
 308         EXIT;
 309 }
 310
 311 /*
 312  * Allocate and initialize a qsd_qtype_info structure for quota type \qtype.
 313  * This opens the accounting object and initializes the proc file.
 314  * It's called on OSD start when the qsd_prepare() is invoked on the qsd
 315  * instance.
 316  *
 317  * \param env  - the environment passed by the caller
 318  * \param qsd  - is the qsd instance which will be in charge of the new
 319  *               qsd_qtype_info instance.
 320  * \param qtype - is quota type to set up
 321  *
 322  * \retval - 0 on success and qsd->qsd_type_array[qtype] is allocated,
 323  *           appropriate error on failure
 324  */
 325 static int qsd_qtype_init(const struct lu_env *env, struct qsd_instance *qsd,
 326                           int qtype)
 327 {
 328         struct qsd_qtype_info   *qqi;
 329         int                      rc;
 330         struct obd_uuid          uuid;
 331         ENTRY;
 332
 333         LASSERT(qsd->qsd_type_array[qtype] == NULL);
 334
 335         /* allocate structure for this quota type */
 336         OBD_ALLOC_PTR(qqi);
 337         if (qqi == NULL)
 338                 RETURN(-ENOMEM);
 339         qsd->qsd_type_array[qtype] = qqi;
 340         cfs_atomic_set(&qqi->qqi_ref, 1); /* referenced from qsd */
 341
 342         /* set backpointer and other parameters */
 343         qqi->qqi_qsd   = qsd;
 344         qqi->qqi_qtype = qtype;
 345         lu_ref_init(&qqi->qqi_reference);
 346         lquota_generate_fid(&qqi->qqi_fid, qsd->qsd_pool_id, QSD_RES_TYPE(qsd),
 347                             qtype);
 348         qqi->qqi_glb_uptodate = false;
 349         qqi->qqi_slv_uptodate = false;
 350         qqi->qqi_reint        = false;
 351         cfs_waitq_init(&qqi->qqi_reint_thread.t_ctl_waitq);
 352         thread_set_flags(&qqi->qqi_reint_thread, SVC_STOPPED);
 353         CFS_INIT_LIST_HEAD(&qqi->qqi_deferred_glb);
 354         CFS_INIT_LIST_HEAD(&qqi->qqi_deferred_slv);
 355         memset(&qqi->qqi_lockh, 0, sizeof(qqi->qqi_lockh));
 356
 357         /* open accounting object */
 358         LASSERT(qqi->qqi_acct_obj == NULL);
 359         qqi->qqi_acct_obj = acct_obj_lookup(env, qsd->qsd_dev, qtype);
 360         if (qqi->qqi_acct_obj == NULL) {
 361                 LCONSOLE_ERROR("%s: No %s space accounting support. Please use "
 362                                "tunefs.lustre --quota option to enable quota "
 363                                "accounting.\n",
 364                                qsd->qsd_svname, QTYPE_NAME(qtype));
 365                 GOTO(out, rc = -ENOENT);
 366         }
 367
 368         /* open global index copy */
 369         LASSERT(qqi->qqi_glb_obj == NULL);
 370         qqi->qqi_glb_obj = lquota_disk_glb_find_create(env, qsd->qsd_dev,
 371                                                        qsd->qsd_root,
 372                                                        &qqi->qqi_fid, true);
 373         if (IS_ERR(qqi->qqi_glb_obj)) {
 374                 CERROR("%s: can't open global index copy "DFID" %ld\n",
 375                        qsd->qsd_svname, PFID(&qqi->qqi_fid),
 376                        PTR_ERR(qqi->qqi_glb_obj));
 377                 GOTO(out, rc = PTR_ERR(qqi->qqi_glb_obj));
 378         }
 379         qqi->qqi_glb_ver = dt_version_get(env, qqi->qqi_glb_obj);
 380
 381         /* open slave index copy */
 382         LASSERT(qqi->qqi_slv_obj == NULL);
 383         obd_str2uuid(&uuid, qsd->qsd_svname);
 384         qqi->qqi_slv_obj = lquota_disk_slv_find_create(env, qsd->qsd_dev,
 385                                                        qsd->qsd_root,
 386                                                        &qqi->qqi_fid, &uuid,
 387                                                        true);
 388         if (IS_ERR(qqi->qqi_slv_obj)) {
 389                 CERROR("%s: can't open slave index copy "DFID" %ld\n",
 390                        qsd->qsd_svname, PFID(&qqi->qqi_fid),
 391                        PTR_ERR(qqi->qqi_slv_obj));
 392                 GOTO(out, rc = PTR_ERR(qqi->qqi_slv_obj));
 393         }
 394         qqi->qqi_slv_ver = dt_version_get(env, qqi->qqi_slv_obj);
 395
 396         /* allocate site */
 397         qqi->qqi_site = lquota_site_alloc(env, qqi, false, qtype, &qsd_lqe_ops);
 398         if (IS_ERR(qqi->qqi_site)) {
 399                 CERROR("%s: can't allocate site "DFID" %ld\n", qsd->qsd_svname,
 400                        PFID(&qqi->qqi_fid), PTR_ERR(qqi->qqi_site));
 401                 GOTO(out, rc = PTR_ERR(qqi->qqi_site));
 402         }
 403
 404         /* register proc entry for accounting object */
 405         rc = lprocfs_seq_create(qsd->qsd_proc,
 406                                 qtype == USRQUOTA ? "acct_user" : "acct_group",
 407                                 0444, &lprocfs_quota_seq_fops,
 408                                 qqi->qqi_acct_obj);
 409         if (rc) {
 410                 CERROR("%s: can't add procfs entry for accounting file %d\n",
 411                        qsd->qsd_svname, rc);
 412                 GOTO(out, rc);
 413         }
 414         EXIT;
 415 out:
 416         if (rc)
 417                 qsd_qtype_fini(env, qsd, qtype);
 418         return rc;
 419 }
 420
 421 /*
 422  * Release a qsd_instance. Companion of qsd_init(). This releases all data
 423  * structures associated with the quota slave (on-disk objects, lquota entry
 424  * tables, ...).
 425  * This function should be called when the OSD is shutting down.
 426  *
 427  * \param env - is the environment passed by the caller
 428  * \param qsd - is the qsd instance to shutdown
 429  */
 430 void qsd_fini(const struct lu_env *env, struct qsd_instance *qsd)
 431 {
 432         int     qtype;
 433         ENTRY;
 434
 435         if (unlikely(qsd == NULL))
 436                 RETURN_EXIT;
 437
 438         CDEBUG(D_QUOTA, "%s: initiating QSD shutdown\n", qsd->qsd_svname);
 439         cfs_write_lock(&qsd->qsd_lock);
 440         qsd->qsd_stopping = true;
 441         cfs_write_unlock(&qsd->qsd_lock);
 442
 443         /* remove from the list of fsinfo */
 444         if (!cfs_list_empty(&qsd->qsd_link)) {
 445                 LASSERT(qsd->qsd_fsinfo != NULL);
 446                 cfs_down(&qsd->qsd_fsinfo->qfs_sem);
 447                 cfs_list_del_init(&qsd->qsd_link);
 448                 cfs_up(&qsd->qsd_fsinfo->qfs_sem);
 449         }
 450
 451         /* remove qsd proc entry */
 452         if (qsd->qsd_proc != NULL) {
 453                 lprocfs_remove(&qsd->qsd_proc);
 454                 qsd->qsd_proc = NULL;
 455         }
 456
 457         /* stop the writeback thread */
 458         qsd_stop_upd_thread(qsd);
 459
 460         /* shutdown the reintegration threads */
 461         for (qtype = USRQUOTA; qtype < MAXQUOTAS; qtype++) {
 462                 if (qsd->qsd_type_array[qtype] == NULL)
 463                         continue;
 464                 qsd_stop_reint_thread(qsd->qsd_type_array[qtype]);
 465         }
 466
 467         /* release reference on namespace */
 468         if (qsd->qsd_ns != NULL) {
 469                 ldlm_namespace_put(qsd->qsd_ns);
 470                 qsd->qsd_ns = NULL;
 471         }
 472
 473         /* free per-quota type data */
 474         for (qtype = USRQUOTA; qtype < MAXQUOTAS; qtype++)
 475                 qsd_qtype_fini(env, qsd, qtype);
 476
 477         /* deregister connection to the quota master */
 478         qsd->qsd_exp_valid = false;
 479         lustre_deregister_osp_item(&qsd->qsd_exp);
 480
 481         /* release per-filesystem information */
 482         if (qsd->qsd_fsinfo != NULL)
 483                 qsd_put_fsinfo(qsd->qsd_fsinfo);
 484
 485         /* release quota root directory */
 486         if (qsd->qsd_root != NULL) {
 487                 lu_object_put(env, &qsd->qsd_root->do_lu);
 488                 qsd->qsd_root = NULL;
 489         }
 490
 491         /* release reference on dt_device */
 492         if (qsd->qsd_dev != NULL) {
 493                 lu_ref_del(&qsd->qsd_dev->dd_lu_dev.ld_reference, "qsd", qsd);
 494                 lu_device_put(&qsd->qsd_dev->dd_lu_dev);
 495                 qsd->qsd_dev = NULL;
 496         }
 497
 498         CDEBUG(D_QUOTA, "%s: QSD shutdown completed\n", qsd->qsd_svname);
 499         OBD_FREE_PTR(qsd);
 500         EXIT;
 501 }
 502 EXPORT_SYMBOL(qsd_fini);
 503
 504 /*
 505  * Create a new qsd_instance to be associated with backend osd device
 506  * identified by \dev.
 507  *
 508  * \param env    - the environment passed by the caller
 509  * \param svname - is the service name of the OSD device creating this instance
 510  * \param dev    - is the dt_device where to store quota index files
 511  * \param osd_proc - is the procfs parent directory where to create procfs file
 512  *                   related to this new qsd instance
 513  *
 514  * \retval - pointer to new qsd_instance associated with dev \dev on success,
 515  *           appropriate error on failure
 516  */
 517 struct qsd_instance *qsd_init(const struct lu_env *env, char *svname,
 518                               struct dt_device *dev,
 519                               cfs_proc_dir_entry_t *osd_proc)
 520 {
 521         struct qsd_thread_info  *qti = qsd_info(env);
 522         struct qsd_instance     *qsd;
 523         int                      rc, type, idx;
 524         ENTRY;
 525
 526         /* only configure qsd for MDT & OST */
 527         type = server_name2index(svname, &idx, NULL);
 528         if (type != LDD_F_SV_TYPE_MDT && type != LDD_F_SV_TYPE_OST)
 529                 RETURN(NULL);
 530
 531         /* allocate qsd instance */
 532         OBD_ALLOC_PTR(qsd);
 533         if (qsd == NULL)
 534                 RETURN(ERR_PTR(-ENOMEM));
 535
 536         /* generic initializations */
 537         cfs_rwlock_init(&qsd->qsd_lock);
 538         CFS_INIT_LIST_HEAD(&qsd->qsd_link);
 539         thread_set_flags(&qsd->qsd_upd_thread, SVC_STOPPED);
 540         cfs_waitq_init(&qsd->qsd_upd_thread.t_ctl_waitq);
 541         CFS_INIT_LIST_HEAD(&qsd->qsd_upd_list);
 542         cfs_spin_lock_init(&qsd->qsd_adjust_lock);
 543         CFS_INIT_LIST_HEAD(&qsd->qsd_adjust_list);
 544         qsd->qsd_prepared = false;
 545         qsd->qsd_started = false;
 546
 547         /* copy service name */
 548         strncpy(qsd->qsd_svname, svname, MAX_OBD_NAME);
 549
 550         /* grab reference on osd device */
 551         lu_device_get(&dev->dd_lu_dev);
 552         lu_ref_add(&dev->dd_lu_dev.ld_reference, "qsd", qsd);
 553         qsd->qsd_dev = dev;
 554
 555         /* we only support pool ID 0 (default data or metadata pool) for the
 556          * time being. A different pool ID could be assigned to this target via
 557          * the configuration log in the future */
 558         qsd->qsd_pool_id  = 0;
 559
 560         /* get fsname from svname */
 561         rc = server_name2fsname(svname, qti->qti_buf, NULL);
 562         if (rc) {
 563                 CERROR("%s: fail to extract filesystem name\n", svname);
 564                 GOTO(out, rc);
 565         }
 566
 567         /* look up quota setting for the filesystem the target belongs to */
 568         qsd->qsd_fsinfo = qsd_get_fsinfo(qti->qti_buf, 1);
 569         if (qsd->qsd_fsinfo == NULL) {
 570                 CERROR("%s: failed to locate filesystem information\n", svname);
 571                 GOTO(out, rc = -EINVAL);
 572         }
 573
 574         /* add in the list of lquota_fsinfo */
 575         cfs_down(&qsd->qsd_fsinfo->qfs_sem);
 576         list_add_tail(&qsd->qsd_link, &qsd->qsd_fsinfo->qfs_qsd_list);
 577         cfs_up(&qsd->qsd_fsinfo->qfs_sem);
 578
 579         /* register procfs directory */
 580         qsd->qsd_proc = lprocfs_register(QSD_DIR, osd_proc,
 581                                          lprocfs_quota_qsd_vars, qsd);
 582         if (IS_ERR(qsd->qsd_proc)) {
 583                 rc = PTR_ERR(qsd->qsd_proc);
 584                 qsd->qsd_proc = NULL;
 585                 CERROR("%s: fail to create quota slave proc entry (%d)\n",
 586                        svname, rc);
 587                 GOTO(out, rc);
 588         }
 589         EXIT;
 590 out:
 591         if (rc) {
 592                 qsd_fini(env, qsd);
 593                 return ERR_PTR(rc);
 594         }
 595         RETURN(qsd);
 596 }
 597 EXPORT_SYMBOL(qsd_init);
 598
 599 /*
 600  * Initialize on-disk structures in order to manage quota enforcement for
 601  * the target associated with the qsd instance \qsd and starts the reintegration
 602  * procedure for each quota type as soon as possible.
 603  * The last step of the reintegration will be completed once qsd_start() is
 604  * called, at which points the space reconciliation with the master will be
 605  * executed.
 606  * This function must be called when the server stack is fully configured,
 607  * typically when ->ldo_prepare is called across the stack.
 608  *
 609  * \param env - the environment passed by the caller
 610  * \param qsd - is qsd_instance to prepare
 611  *
 612  * \retval - 0 on success, appropriate error on failure
 613  */
 614 int qsd_prepare(const struct lu_env *env, struct qsd_instance *qsd)
 615 {
 616         struct qsd_thread_info  *qti = qsd_info(env);
 617         int                      qtype, rc = 0;
 618         ENTRY;
 619
 620         if (unlikely(qsd == NULL))
 621                 RETURN(0);
 622
 623         cfs_read_lock(&qsd->qsd_lock);
 624         if (qsd->qsd_prepared) {
 625                 CERROR("%s: qsd instance already prepared\n", qsd->qsd_svname);
 626                 rc = -EALREADY;
 627         }
 628         cfs_read_unlock(&qsd->qsd_lock);
 629         if (rc)
 630                 RETURN(rc);
 631
 632         /* Record whether this qsd instance is managing quota enforcement for a
 633          * MDT (i.e. inode quota) or OST (block quota) */
 634         if (lu_device_is_md(qsd->qsd_dev->dd_lu_dev.ld_site->ls_top_dev)) {
 635                 qsd->qsd_is_md = true;
 636                 qsd->qsd_sync_threshold = LQUOTA_LEAST_QUNIT(LQUOTA_RES_MD);
 637         } else {
 638                 qsd->qsd_sync_threshold = LQUOTA_LEAST_QUNIT(LQUOTA_RES_DT);
 639         }
 640
 641         /* look-up on-disk directory for the quota slave */
 642         qsd->qsd_root = lquota_disk_dir_find_create(env, qsd->qsd_dev, NULL,
 643                                                     QSD_DIR);
 644         if (IS_ERR(qsd->qsd_root)) {
 645                 rc = PTR_ERR(qsd->qsd_root);
 646                 qsd->qsd_root = NULL;
 647                 CERROR("%s: failed to create quota slave root dir (%d)\n",
 648                        qsd->qsd_svname, rc);
 649                 RETURN(rc);
 650         }
 651
 652         /* initialize per-quota type data */
 653         for (qtype = USRQUOTA; qtype < MAXQUOTAS; qtype++) {
 654                 rc = qsd_qtype_init(env, qsd, qtype);
 655                 if (rc)
 656                         RETURN(rc);
 657         }
 658
 659         /* pools successfully setup, mark the qsd as prepared */
 660         cfs_write_lock(&qsd->qsd_lock);
 661         qsd->qsd_prepared = true;
 662         cfs_write_unlock(&qsd->qsd_lock);
 663
 664         /* start reintegration thread for each type, if required */
 665         for (qtype = USRQUOTA; qtype < MAXQUOTAS; qtype++) {
 666                 struct qsd_qtype_info   *qqi = qsd->qsd_type_array[qtype];
 667
 668                 rc = qsd_start_reint_thread(qqi);
 669                 if (rc) {
 670                         CERROR("%s: failed to start reint thread for type %s "
 671                                "(%d)\n", qsd->qsd_svname, QTYPE_NAME(qtype),
 672                                rc);
 673                         RETURN(rc);
 674                 }
 675         }
 676
 677         /* start writeback thread */
 678         rc = qsd_start_upd_thread(qsd);
 679         if (rc) {
 680                 CERROR("%s: failed to start writeback thread (%d)\n",
 681                        qsd->qsd_svname, rc);
 682                 RETURN(rc);
 683         }
 684
 685         /* generate osp name */
 686         rc = tgt_name2ospname((char *)qsd->qsd_svname, qti->qti_buf);
 687         if (rc) {
 688                 CERROR("%s: failed to generate ospname (%d)\n",
 689                        qsd->qsd_svname, rc);
 690                 RETURN(rc);
 691         }
 692
 693         /* the connection callback will start the reintegration
 694          * procedure if quota is enabled */
 695         rc = lustre_register_osp_item(qti->qti_buf, &qsd->qsd_exp,
 696                                       qsd_conn_callback, (void *)qsd);
 697         if (rc) {
 698                 CERROR("%s: fail to get connection to master (%d)\n",
 699                        qsd->qsd_svname, rc);
 700                 RETURN(rc);
 701         }
 702
 703         RETURN(0);
 704 }
 705 EXPORT_SYMBOL(qsd_prepare);
 706
 707 /*
 708  * Start a qsd instance. This will complete the last step of the reintegration
 709  * procedure as soon as possible (provided that the master is reachable).
 710  * This should be called when recovery has been completed and quota should now
 711  * be enforced on every operations.
 712  *
 713  * \param env - the environment passed by the caller
 714  * \param qsd - is the qsd instance associated with the osd device to start
 715  */
 716 int qsd_start(const struct lu_env *env, struct qsd_instance *qsd)
 717 {
 718         int     type, rc = 0;
 719         ENTRY;
 720
 721         if (unlikely(qsd == NULL))
 722                 RETURN(0);
 723
 724         cfs_write_lock(&qsd->qsd_lock);
 725         if (!qsd->qsd_prepared) {
 726                 CERROR("%s: can't start qsd instance since it was properly "
 727                        "initialized\n", qsd->qsd_svname);
 728                 rc = -EFAULT;
 729         } else if (qsd->qsd_started) {
 730                 CERROR("%s: qsd instance already started\n", qsd->qsd_svname);
 731                 rc = -EALREADY;
 732         } else {
 733                 /* notify that the qsd_instance is now started */
 734                 qsd->qsd_started = true;
 735         }
 736         cfs_write_unlock(&qsd->qsd_lock);
 737
 738         if (rc)
 739                 RETURN(rc);
 740
 741         /* Trigger the 3rd step of reintegration: If usage > granted, acquire
 742          * up to usage; If usage < granted, release down to usage.  */
 743         for (type = USRQUOTA; type < MAXQUOTAS; type++) {
 744                 struct qsd_qtype_info   *qqi = qsd->qsd_type_array[type];
 745                 cfs_waitq_signal(&qqi->qqi_reint_thread.t_ctl_waitq);
 746         }
 747
 748         RETURN(rc);
 749 }
 750 EXPORT_SYMBOL(qsd_start);
 751
 752 void lustre_register_quota_process_config(int (*qpc)(struct lustre_cfg *lcfg));
 753
 754 /*
 755  * Global initialization performed at module load time
 756  */
 757 int qsd_glb_init(void)
 758 {
 759         int     rc;
 760
 761         rc = lu_kmem_init(qsd_caches);
 762         if (rc)
 763                 return rc;
 764
 765         qsd_key_init_generic(&qsd_thread_key, NULL);
 766         lu_context_key_register(&qsd_thread_key);
 767         lustre_register_quota_process_config(qsd_process_config);
 768
 769         return 0;
 770 }
 771
 772 /*
 773  * Companion of qsd_glb_init() called at module unload time
 774  */
 775 void qsd_glb_fini(void)
 776 {
 777         lustre_register_quota_process_config(NULL);
 778         lu_kmem_fini(qsd_caches);
 779         lu_context_key_degister(&qsd_thread_key);
 780 }