X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Fquota%2Fqsd_lib.c;h=277791b08e59cde130440c11420b4b867ab3abcf;hp=1430410fff849cd4e79e7ba9f09519438c7001a5;hb=3aa4a85d37563db1e87b7da9e621bc33ffad0108;hpb=2d08f9070c8686ee4851036091c966563672ba49

diff --git a/lustre/quota/qsd_lib.c b/lustre/quota/qsd_lib.c
index 1430410..277791b 100644
--- a/lustre/quota/qsd_lib.c
+++ b/lustre/quota/qsd_lib.c
@@ -21,15 +21,32 @@
  * GPL HEADER END
  */
 /*
- * Copyright (c) 2012 Whamcloud, Inc.
+ * Copyright (c) 2012 Intel, Inc.
  * Use is subject to license terms.
  *
- * Author: Johann Lombardi <johann@whamcloud.com>
- * Author: Niu    Yawei    <niu@whamcloud.com>
+ * Author: Johann Lombardi <johann.lombardi@intel.com>
+ * Author: Niu    Yawei    <yawei.niu@intel.com>
  */
 
 /*
  * Quota Slave Driver (QSD) management.
+ *
+ * The quota slave feature is implemented under the form of a library called
+ * QSD. Each OSD device should create a QSD instance via qsd_init() which will
+ * be used to manage quota enforcement for this device. This implies:
+ * - completing the reintegration procedure with the quota master (aka QMT, see
+ *   qmt_dev.c) to retrieve the latest quota settings and space distribution.
+ * - managing quota locks in order to be notified of configuration changes.
+ * - acquiring space from the QMT when quota space for a given user/group is
+ *   close to exhaustion.
+ * - allocating quota space to service threads for local request processing.
+ *
+ * Once the QSD instance created, the OSD device should invoke qsd_start()
+ * when recovery is completed. This notifies the QSD that we are about to
+ * process new requests on which quota should be strictly enforced.
+ * Then, qsd_op_begin/end can be used to reserve/release/pre-acquire quota space
+ * for/after each operation until shutdown where the QSD instance should be
+ * freed via qsd_fini().
  */
 
 #ifndef EXPORT_SYMTAB
@@ -38,8 +55,22 @@
 
 #define DEBUG_SUBSYSTEM S_LQUOTA
 
+#include <obd_class.h>
 #include "qsd_internal.h"
 
+cfs_mem_cache_t *upd_kmem;
+
+struct lu_kmem_descr qsd_caches[] = {
+	{
+		.ckd_cache = &upd_kmem,
+		.ckd_name  = "upd_kmem",
+		.ckd_size  = sizeof(struct qsd_upd_rec)
+	},
+	{
+		.ckd_cache = NULL
+	}
+};
+
 /* define qsd thread key */
 LU_KEY_INIT_FINI(qsd, struct qsd_thread_info);
 LU_CONTEXT_KEY_DEFINE(qsd, LCT_MD_THREAD | LCT_DT_THREAD | LCT_LOCAL);
@@ -50,24 +81,108 @@ static int lprocfs_qsd_rd_state(char *page, char **start, off_t off,
 				int count, int *eof, void *data)
 {
 	struct qsd_instance	*qsd = (struct qsd_instance *)data;
+	char			 enabled[5];
+	int			 rc;
+
+	LASSERT(qsd != NULL);
+
+	memset(enabled, 0, sizeof(enabled));
+	if (qsd_type_enabled(qsd, USRQUOTA))
+		strcat(enabled, "u");
+	if (qsd_type_enabled(qsd, GRPQUOTA))
+		strcat(enabled, "g");
+	if (strlen(enabled) == 0)
+		strcat(enabled, "none");
+
+	rc = snprintf(page, count,
+		      "target name:    %s\n"
+		      "pool ID:        %d\n"
+		      "type:           %s\n"
+		      "quota enabled:  %s\n"
+		      "conn to master: %s\n",
+		      qsd->qsd_svname, qsd->qsd_pool_id,
+		      qsd->qsd_is_md ? "md" : "dt", enabled,
+		      qsd->qsd_exp_valid ? "setup" : "not setup yet");
+
+	if (qsd->qsd_prepared)
+		rc +=  snprintf(page + rc, count - rc,
+				"user uptodate:  glb[%d],slv[%d],reint[%d]\n"
+				"group uptodate: glb[%d],slv[%d],reint[%d]\n",
+				qsd->qsd_type_array[USRQUOTA]->qqi_glb_uptodate,
+				qsd->qsd_type_array[USRQUOTA]->qqi_slv_uptodate,
+				qsd->qsd_type_array[USRQUOTA]->qqi_reint,
+				qsd->qsd_type_array[GRPQUOTA]->qqi_glb_uptodate,
+				qsd->qsd_type_array[GRPQUOTA]->qqi_slv_uptodate,
+				qsd->qsd_type_array[GRPQUOTA]->qqi_reint);
+	return rc;
+}
 
+static int lprocfs_qsd_rd_enabled(char *page, char **start, off_t off,
+				  int count, int *eof, void *data)
+{
+	struct qsd_instance	*qsd = (struct qsd_instance *)data;
+	char			 enabled[5];
 	LASSERT(qsd != NULL);
 
-	return snprintf(page, count,
-			"target name:    %s\n"
-			"pool ID:        %d\n"
-			"type:           %s\n"
-			"quota enabled:  none\n",
-			qsd->qsd_svname, qsd->qsd_pool_id,
-			qsd->qsd_is_md ? "md" : "dt");
+	memset(enabled, 0, sizeof(enabled));
+	if (qsd_type_enabled(qsd, USRQUOTA))
+		strcat(enabled, "u");
+	if (qsd_type_enabled(qsd, GRPQUOTA))
+		strcat(enabled, "g");
+	if (strlen(enabled) == 0)
+		strcat(enabled, "none");
+
+	return snprintf(page, count, "%s\n", enabled);
 }
 
 static struct lprocfs_vars lprocfs_quota_qsd_vars[] = {
 	{ "info", lprocfs_qsd_rd_state, 0, 0},
+	{ "enabled", lprocfs_qsd_rd_enabled, 0, 0},
 	{ NULL }
 };
 
 /*
+ * Callback function invoked by the OSP layer when the connection to the master
+ * has been set up.
+ *
+ * \param data - is a pointer to the qsd_instance
+ *
+ * \retval - 0 on success, appropriate error on failure
+ */
+static int qsd_conn_callback(void *data)
+{
+	struct qsd_instance *qsd = (struct qsd_instance *)data;
+	int                  type;
+	ENTRY;
+
+	/* qsd_exp should now be valid */
+	LASSERT(qsd->qsd_exp);
+
+	/* grab reference on namespace */
+	ldlm_namespace_get(class_exp2obd(qsd->qsd_exp)->obd_namespace);
+	qsd->qsd_ns = class_exp2obd(qsd->qsd_exp)->obd_namespace;
+
+	cfs_write_lock(&qsd->qsd_lock);
+	/* notify that qsd_exp is now valid */
+	qsd->qsd_exp_valid = true;
+	cfs_write_unlock(&qsd->qsd_lock);
+
+	/* Now that the connection to master is setup, we can initiate the
+	 * reintegration procedure for quota types which are enabled.
+	 * It is worth noting that, if the qsd_instance hasn't been started
+	 * already, then we can only complete the first two steps of the
+	 * reintegration procedure (i.e. global lock enqueue and slave
+	 * index transfer) since the space usage reconciliation (i.e.
+	 * step 3) will have to wait for qsd_start() to be called */
+	for (type = USRQUOTA; type < MAXQUOTAS; type++) {
+		struct qsd_qtype_info *qqi = qsd->qsd_type_array[type];
+		cfs_waitq_signal(&qqi->qqi_reint_thread.t_ctl_waitq);
+	}
+
+	RETURN(0);
+}
+
+/*
  * Release qsd_qtype_info structure which contains data associated with a
  * given quota type. This releases the accounting objects.
  * It's called on OSD cleanup when the qsd instance is released.
@@ -88,6 +203,20 @@ static void qsd_qtype_fini(const struct lu_env *env, struct qsd_instance *qsd,
 	qqi = qsd->qsd_type_array[qtype];
 	qsd->qsd_type_array[qtype] = NULL;
 
+	/* all deferred work lists should be empty */
+	LASSERT(cfs_list_empty(&qqi->qqi_deferred_glb));
+	LASSERT(cfs_list_empty(&qqi->qqi_deferred_slv));
+
+	/* shutdown lquota site */
+	if (qqi->qqi_site != NULL && !IS_ERR(qqi->qqi_site)) {
+		lquota_site_free(env, qqi->qqi_site);
+		qqi->qqi_site = NULL;
+	}
+
+	/* by now, all qqi users should have gone away */
+	LASSERT(cfs_atomic_read(&qqi->qqi_ref) == 1);
+	lu_ref_fini(&qqi->qqi_reference);
+
 	/* release accounting object */
 	if (qqi->qqi_acct_obj != NULL && !IS_ERR(qqi->qqi_acct_obj)) {
 		lu_object_put(env, &qqi->qqi_acct_obj->do_lu);
@@ -115,7 +244,8 @@ static void qsd_qtype_fini(const struct lu_env *env, struct qsd_instance *qsd,
 /*
  * Allocate and initialize a qsd_qtype_info structure for quota type \qtype.
  * This opens the accounting object and initializes the proc file.
- * It's called on OSD start when the qsd instance is created.
+ * It's called on OSD start when the qsd_prepare() is invoked on the qsd
+ * instance.
  *
  * \param env  - the environment passed by the caller
  * \param qsd  - is the qsd instance which will be in charge of the new
@@ -140,22 +270,33 @@ static int qsd_qtype_init(const struct lu_env *env, struct qsd_instance *qsd,
 	if (qqi == NULL)
 		RETURN(-ENOMEM);
 	qsd->qsd_type_array[qtype] = qqi;
+	cfs_atomic_set(&qqi->qqi_ref, 1); /* referenced from qsd */
 
 	/* set backpointer and other parameters */
 	qqi->qqi_qsd   = qsd;
 	qqi->qqi_qtype = qtype;
+	lu_ref_init(&qqi->qqi_reference);
 	lquota_generate_fid(&qqi->qqi_fid, qsd->qsd_pool_id, QSD_RES_TYPE(qsd),
 			    qtype);
-
-        /* open accounting object */
-        LASSERT(qqi->qqi_acct_obj == NULL);
-	qqi->qqi_acct_obj = acct_obj_lookup(env, qsd->qsd_dev,
-					    qtype == USRQUOTA ? ACCT_USER_OID
-							      : ACCT_GROUP_OID);
-	/* don't print any error message on failure in order not to confuse
-	 * non-OFD user (e.g. 2.3 MDT stack) */
-	if (IS_ERR(qqi->qqi_acct_obj))
-		qqi->qqi_acct_obj = NULL;
+	qqi->qqi_glb_uptodate = false;
+	qqi->qqi_slv_uptodate = false;
+	qqi->qqi_reint        = false;
+	cfs_waitq_init(&qqi->qqi_reint_thread.t_ctl_waitq);
+	thread_set_flags(&qqi->qqi_reint_thread, SVC_STOPPED);
+	CFS_INIT_LIST_HEAD(&qqi->qqi_deferred_glb);
+	CFS_INIT_LIST_HEAD(&qqi->qqi_deferred_slv);
+	memset(&qqi->qqi_lockh, 0, sizeof(qqi->qqi_lockh));
+
+	/* open accounting object */
+	LASSERT(qqi->qqi_acct_obj == NULL);
+	qqi->qqi_acct_obj = acct_obj_lookup(env, qsd->qsd_dev, qtype);
+	if (qqi->qqi_acct_obj == NULL) {
+		LCONSOLE_ERROR("%s: No %s space accounting support. Please use "
+			       "tunefs.lustre --quota option to enable quota "
+			       "accounting.\n",
+			       qsd->qsd_svname, QTYPE_NAME(qtype));
+		GOTO(out, rc = -ENOENT);
+	}
 
 	/* open global index copy */
 	LASSERT(qqi->qqi_glb_obj == NULL);
@@ -185,17 +326,24 @@ static int qsd_qtype_init(const struct lu_env *env, struct qsd_instance *qsd,
 	}
 	qqi->qqi_slv_ver = dt_version_get(env, qqi->qqi_slv_obj);
 
+	/* allocate site */
+	qqi->qqi_site = lquota_site_alloc(env, qqi, false, qtype, &qsd_lqe_ops);
+	if (IS_ERR(qqi->qqi_site)) {
+		CERROR("%s: can't allocate site "DFID" %ld\n", qsd->qsd_svname,
+		       PFID(&qqi->qqi_fid), PTR_ERR(qqi->qqi_site));
+		GOTO(out, rc = PTR_ERR(qqi->qqi_site));
+	}
+
 	/* register proc entry for accounting object */
 	rc = lprocfs_seq_create(qsd->qsd_proc,
 				qtype == USRQUOTA ? "acct_user" : "acct_group",
 				0444, &lprocfs_quota_seq_fops,
 				qqi->qqi_acct_obj);
 	if (rc) {
-		CWARN("%s: can't add procfs entry for accounting file %d\n",
-		      qsd->qsd_svname, rc);
+		CERROR("%s: can't add procfs entry for accounting file %d\n",
+		       qsd->qsd_svname, rc);
 		GOTO(out, rc);
 	}
-
 	EXIT;
 out:
 	if (rc)
@@ -205,7 +353,8 @@ out:
 
 /*
  * Release a qsd_instance. Companion of qsd_init(). This releases all data
- * structures associated with the quota slave.
+ * structures associated with the quota slave (on-disk objects, lquota entry
+ * tables, ...).
  * This function should be called when the OSD is shutting down.
  *
  * \param env - is the environment passed by the caller
@@ -217,20 +366,54 @@ void qsd_fini(const struct lu_env *env, struct qsd_instance *qsd)
 	ENTRY;
 
 	CDEBUG(D_QUOTA, "%s: initiating QSD shutdown\n", qsd->qsd_svname);
+	cfs_write_lock(&qsd->qsd_lock);
 	qsd->qsd_stopping = true;
+	cfs_write_unlock(&qsd->qsd_lock);
+
+	/* remove from the list of fsinfo */
+	if (!cfs_list_empty(&qsd->qsd_link)) {
+		LASSERT(qsd->qsd_fsinfo != NULL);
+		cfs_down(&qsd->qsd_fsinfo->qfs_sem);
+		cfs_list_del_init(&qsd->qsd_link);
+		cfs_up(&qsd->qsd_fsinfo->qfs_sem);
+	}
 
 	/* remove qsd proc entry */
-	if (qsd->qsd_proc != NULL && !IS_ERR(qsd->qsd_proc)) {
+	if (qsd->qsd_proc != NULL) {
 		lprocfs_remove(&qsd->qsd_proc);
 		qsd->qsd_proc = NULL;
 	}
 
+	/* stop the writeback thread */
+	qsd_stop_upd_thread(qsd);
+
+	/* shutdown the reintegration threads */
+	for (qtype = USRQUOTA; qtype < MAXQUOTAS; qtype++) {
+		if (qsd->qsd_type_array[qtype] == NULL)
+			continue;
+		qsd_stop_reint_thread(qsd->qsd_type_array[qtype]);
+	}
+
+	/* release reference on namespace */
+	if (qsd->qsd_ns != NULL) {
+		ldlm_namespace_put(qsd->qsd_ns);
+		qsd->qsd_ns = NULL;
+	}
+
 	/* free per-quota type data */
 	for (qtype = USRQUOTA; qtype < MAXQUOTAS; qtype++)
 		qsd_qtype_fini(env, qsd, qtype);
 
+	/* deregister connection to the quota master */
+	qsd->qsd_exp_valid = false;
+	lustre_deregister_osp_item(&qsd->qsd_exp);
+
+	/* release per-filesystem information */
+	if (qsd->qsd_fsinfo != NULL)
+		qsd_put_fsinfo(qsd->qsd_fsinfo);
+
 	/* release quota root directory */
-	if (qsd->qsd_root != NULL && !IS_ERR(qsd->qsd_root)) {
+	if (qsd->qsd_root != NULL) {
 		lu_object_put(env, &qsd->qsd_root->do_lu);
 		qsd->qsd_root = NULL;
 	}
@@ -242,6 +425,7 @@ void qsd_fini(const struct lu_env *env, struct qsd_instance *qsd)
 		qsd->qsd_dev = NULL;
 	}
 
+	CDEBUG(D_QUOTA, "%s: QSD shutdown completed\n", qsd->qsd_svname);
 	OBD_FREE_PTR(qsd);
 	EXIT;
 }
@@ -249,8 +433,7 @@ EXPORT_SYMBOL(qsd_fini);
 
 /*
  * Create a new qsd_instance to be associated with backend osd device
- * identified by \dev. For now, this function just create procfs files which
- * dumps the accounting information
+ * identified by \dev.
  *
  * \param env    - the environment passed by the caller
  * \param svname - is the service name of the OSD device creating this instance
@@ -265,15 +448,32 @@ struct qsd_instance *qsd_init(const struct lu_env *env, char *svname,
 			      struct dt_device *dev,
 			      cfs_proc_dir_entry_t *osd_proc)
 {
+	struct qsd_thread_info	*qti = qsd_info(env);
 	struct qsd_instance	*qsd;
-	int			 rc, qtype;
+	int			 rc, type, idx;
 	ENTRY;
 
+	/* only configure qsd for MDT & OST */
+	type = server_name2index(svname, &idx, NULL);
+	if (type != LDD_F_SV_TYPE_MDT && type != LDD_F_SV_TYPE_OST)
+		RETURN(NULL);
+
 	/* allocate qsd instance */
 	OBD_ALLOC_PTR(qsd);
 	if (qsd == NULL)
 		RETURN(ERR_PTR(-ENOMEM));
 
+	/* generic initializations */
+	cfs_rwlock_init(&qsd->qsd_lock);
+	CFS_INIT_LIST_HEAD(&qsd->qsd_link);
+	thread_set_flags(&qsd->qsd_upd_thread, SVC_STOPPED);
+	cfs_waitq_init(&qsd->qsd_upd_thread.t_ctl_waitq);
+	CFS_INIT_LIST_HEAD(&qsd->qsd_upd_list);
+	cfs_spin_lock_init(&qsd->qsd_adjust_lock);
+	CFS_INIT_LIST_HEAD(&qsd->qsd_adjust_list);
+	qsd->qsd_prepared = false;
+	qsd->qsd_started = false;
+
 	/* copy service name */
 	strncpy(qsd->qsd_svname, svname, MAX_OBD_NAME);
 
@@ -287,51 +487,211 @@ struct qsd_instance *qsd_init(const struct lu_env *env, char *svname,
 	 * the configuration log in the future */
 	qsd->qsd_pool_id  = 0;
 
-	/* Record whether this qsd instance is managing quota enforcement for a
-	 * MDT (i.e. inode quota) or OST (block quota) */
-	qsd->qsd_is_md = lu_device_is_md(dev->dd_lu_dev.ld_site->ls_top_dev);
-
-	/* look-up on-disk directory for the quota slave */
-	qsd->qsd_root = lquota_disk_dir_find_create(env, dev, NULL, QSD_DIR);
-	if (IS_ERR(qsd->qsd_root)) {
-		rc = PTR_ERR(qsd->qsd_root);
-		CERROR("%s: failed to create quota slave root dir (%d)\n",
-		       svname, rc);
+	/* get fsname from svname */
+	rc = server_name2fsname(svname, qti->qti_buf, NULL);
+	if (rc) {
+		CERROR("%s: fail to extract filesystem name\n", svname);
 		GOTO(out, rc);
 	}
 
+	/* look up quota setting for the filesystem the target belongs to */
+	qsd->qsd_fsinfo = qsd_get_fsinfo(qti->qti_buf, 1);
+	if (qsd->qsd_fsinfo == NULL) {
+		CERROR("%s: failed to locate filesystem information\n", svname);
+		GOTO(out, rc = -EINVAL);
+	}
+
+	/* add in the list of lquota_fsinfo */
+	cfs_down(&qsd->qsd_fsinfo->qfs_sem);
+	list_add_tail(&qsd->qsd_link, &qsd->qsd_fsinfo->qfs_qsd_list);
+	cfs_up(&qsd->qsd_fsinfo->qfs_sem);
+
 	/* register procfs directory */
 	qsd->qsd_proc = lprocfs_register(QSD_DIR, osd_proc,
 					 lprocfs_quota_qsd_vars, qsd);
 	if (IS_ERR(qsd->qsd_proc)) {
 		rc = PTR_ERR(qsd->qsd_proc);
+		qsd->qsd_proc = NULL;
 		CERROR("%s: fail to create quota slave proc entry (%d)\n",
 		       svname, rc);
 		GOTO(out, rc);
         }
+	EXIT;
+out:
+	if (rc) {
+		qsd_fini(env, qsd);
+		return ERR_PTR(rc);
+	}
+	RETURN(qsd);
+}
+EXPORT_SYMBOL(qsd_init);
+
+/*
+ * Initialize on-disk structures in order to manage quota enforcement for
+ * the target associated with the qsd instance \qsd and starts the reintegration
+ * procedure for each quota type as soon as possible.
+ * The last step of the reintegration will be completed once qsd_start() is
+ * called, at which points the space reconciliation with the master will be
+ * executed.
+ * This function must be called when the server stack is fully configured,
+ * typically when ->ldo_prepare is called across the stack.
+ *
+ * \param env - the environment passed by the caller
+ * \param qsd - is qsd_instance to prepare
+ *
+ * \retval - 0 on success, appropriate error on failure
+ */
+int qsd_prepare(const struct lu_env *env, struct qsd_instance *qsd)
+{
+	struct qsd_thread_info	*qti = qsd_info(env);
+	int			 qtype, rc = 0;
+	ENTRY;
+
+	LASSERT(qsd != NULL);
+
+	cfs_read_lock(&qsd->qsd_lock);
+	if (qsd->qsd_prepared) {
+		CERROR("%s: qsd instance already prepared\n", qsd->qsd_svname);
+		rc = -EALREADY;
+	}
+	cfs_read_unlock(&qsd->qsd_lock);
+	if (rc)
+		RETURN(rc);
+
+	/* Record whether this qsd instance is managing quota enforcement for a
+	 * MDT (i.e. inode quota) or OST (block quota) */
+	if (lu_device_is_md(qsd->qsd_dev->dd_lu_dev.ld_site->ls_top_dev)) {
+		qsd->qsd_is_md = true;
+		qsd->qsd_sync_threshold = LQUOTA_LEAST_QUNIT(LQUOTA_RES_MD);
+	} else {
+		qsd->qsd_sync_threshold = LQUOTA_LEAST_QUNIT(LQUOTA_RES_DT);
+	}
+
+	/* look-up on-disk directory for the quota slave */
+	qsd->qsd_root = lquota_disk_dir_find_create(env, qsd->qsd_dev, NULL,
+						    QSD_DIR);
+	if (IS_ERR(qsd->qsd_root)) {
+		rc = PTR_ERR(qsd->qsd_root);
+		qsd->qsd_root = NULL;
+		CERROR("%s: failed to create quota slave root dir (%d)\n",
+		       qsd->qsd_svname, rc);
+		RETURN(rc);
+	}
 
 	/* initialize per-quota type data */
 	for (qtype = USRQUOTA; qtype < MAXQUOTAS; qtype++) {
 		rc = qsd_qtype_init(env, qsd, qtype);
 		if (rc)
-			GOTO(out, rc);
+			RETURN(rc);
 	}
-out:
+
+	/* pools successfully setup, mark the qsd as prepared */
+	cfs_write_lock(&qsd->qsd_lock);
+	qsd->qsd_prepared = true;
+	cfs_write_unlock(&qsd->qsd_lock);
+
+	/* start reintegration thread for each type, if required */
+	for (qtype = USRQUOTA; qtype < MAXQUOTAS; qtype++) {
+		struct qsd_qtype_info	*qqi = qsd->qsd_type_array[qtype];
+
+		rc = qsd_start_reint_thread(qqi);
+		if (rc) {
+			CERROR("%s: failed to start reint thread for type %s "
+			       "(%d)\n", qsd->qsd_svname, QTYPE_NAME(qtype),
+			       rc);
+			RETURN(rc);
+		}
+	}
+
+	/* start writeback thread */
+	rc = qsd_start_upd_thread(qsd);
 	if (rc) {
-		qsd_fini(env, qsd);
-		return ERR_PTR(rc);
+		CERROR("%s: failed to start writeback thread (%d)\n",
+		       qsd->qsd_svname, rc);
+		RETURN(rc);
 	}
-	RETURN(qsd);
+
+	/* generate osp name */
+	rc = tgt_name2ospname((char *)qsd->qsd_svname, qti->qti_buf);
+	if (rc) {
+		CERROR("%s: failed to generate ospname (%d)\n",
+		       qsd->qsd_svname, rc);
+		RETURN(rc);
+	}
+
+	/* the connection callback will start the reintegration
+	 * procedure if quota is enabled */
+	rc = lustre_register_osp_item(qti->qti_buf, &qsd->qsd_exp,
+				      qsd_conn_callback, (void *)qsd);
+	if (rc) {
+		CERROR("%s: fail to get connection to master (%d)\n",
+		       qsd->qsd_svname, rc);
+		RETURN(rc);
+	}
+
+	RETURN(0);
 }
-EXPORT_SYMBOL(qsd_init);
+EXPORT_SYMBOL(qsd_prepare);
+
+/*
+ * Start a qsd instance. This will complete the last step of the reintegration
+ * procedure as soon as possible (provided that the master is reachable).
+ * This should be called when recovery has been completed and quota should now
+ * be enforced on every operations.
+ *
+ * \param env - the environment passed by the caller
+ * \param qsd - is the qsd instance associated with the osd device to start
+ */
+int qsd_start(const struct lu_env *env, struct qsd_instance *qsd)
+{
+	int	type, rc = 0;
+	ENTRY;
+
+	cfs_write_lock(&qsd->qsd_lock);
+	if (!qsd->qsd_prepared) {
+		CERROR("%s: can't start qsd instance since it was properly "
+		       "initialized\n", qsd->qsd_svname);
+		rc = -EFAULT;
+	} else if (qsd->qsd_started) {
+		CERROR("%s: qsd instance already started\n", qsd->qsd_svname);
+		rc = -EALREADY;
+	} else {
+		/* notify that the qsd_instance is now started */
+		qsd->qsd_started = true;
+	}
+	cfs_write_unlock(&qsd->qsd_lock);
+
+	if (rc)
+		RETURN(rc);
+
+	/* Trigger the 3rd step of reintegration: If usage > granted, acquire
+	 * up to usage; If usage < granted, release down to usage.  */
+	for (type = USRQUOTA; type < MAXQUOTAS; type++) {
+		struct qsd_qtype_info	*qqi = qsd->qsd_type_array[type];
+		cfs_waitq_signal(&qqi->qqi_reint_thread.t_ctl_waitq);
+	}
+
+	RETURN(rc);
+}
+EXPORT_SYMBOL(qsd_start);
+
+void lustre_register_quota_process_config(int (*qpc)(struct lustre_cfg *lcfg));
 
 /*
  * Global initialization performed at module load time
  */
 int qsd_glb_init(void)
 {
+	int	rc;
+
+	rc = lu_kmem_init(qsd_caches);
+	if (rc)
+		return rc;
+
 	qsd_key_init_generic(&qsd_thread_key, NULL);
 	lu_context_key_register(&qsd_thread_key);
+	lustre_register_quota_process_config(qsd_process_config);
+
 	return 0;
 }
 
@@ -340,5 +700,7 @@ int qsd_glb_init(void)
  */
 void qsd_glb_fini(void)
 {
+	lustre_register_quota_process_config(NULL);
+	lu_kmem_fini(qsd_caches);
 	lu_context_key_degister(&qsd_thread_key);
 }