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LU-6245 server: remove types abstraction from quota/target/nodemap code
[fs/lustre-release.git] / lustre / quota / qsd_handler.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, 2014, Intel Corporation.
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 #define DEBUG_SUBSYSTEM S_LQUOTA
32
33 #include "qsd_internal.h"
34
35 /**
36  * helper function bumping lqe_pending_req if there is no quota request in
37  * flight for the lquota entry \a lqe. Otherwise, EBUSY is returned.
38  */
39 static inline int qsd_request_enter(struct lquota_entry *lqe)
40 {
41         /* is there already a quota request in flight? */
42         if (lqe->lqe_pending_req != 0) {
43                 LQUOTA_DEBUG(lqe, "already a request in flight");
44                 return -EBUSY;
45         }
46
47         if (lqe->lqe_pending_rel != 0) {
48                 LQUOTA_ERROR(lqe, "no request in flight with pending_rel=%llu",
49                              lqe->lqe_pending_rel);
50                 LBUG();
51         }
52
53         lqe->lqe_pending_req++;
54         return 0;
55 }
56
57 /**
58  * Companion of qsd_request_enter() dropping lqe_pending_req to 0.
59  */
60 static inline void qsd_request_exit(struct lquota_entry *lqe)
61 {
62         if (lqe->lqe_pending_req != 1) {
63                 LQUOTA_ERROR(lqe, "lqe_pending_req != 1!!!");
64                 LBUG();
65         }
66         lqe->lqe_pending_req--;
67         lqe->lqe_pending_rel = 0;
68         wake_up_all(&lqe->lqe_waiters);
69 }
70
71 /**
72  * Check whether a qsd instance is all set to send quota request to master.
73  * This includes checking whether:
74  * - the connection to master is set up and usable,
75  * - the qsd isn't stopping
76  * - reintegration has been successfully completed and all indexes are
77  *   up-to-date
78  *
79  * \param lqe - is the lquota entry for which we would like to send an quota
80  *              request
81  * \param lockh - is the remote handle of the global lock returned on success
82  *
83  * \retval 0 on success, appropriate error on failure
84  */
85 static int qsd_ready(struct lquota_entry *lqe, struct lustre_handle *lockh)
86 {
87         struct qsd_qtype_info   *qqi = lqe2qqi(lqe);
88         struct qsd_instance     *qsd = qqi->qqi_qsd;
89         struct obd_import       *imp = NULL;
90         struct ldlm_lock        *lock;
91         ENTRY;
92
93         read_lock(&qsd->qsd_lock);
94         /* is the qsd about to shut down? */
95         if (qsd->qsd_stopping) {
96                 read_unlock(&qsd->qsd_lock);
97                 LQUOTA_DEBUG(lqe, "dropping quota req since qsd is stopping");
98                 /* Target is about to shut down, client will retry */
99                 RETURN(-EINPROGRESS);
100         }
101
102         /* is the connection to the quota master ready? */
103         if (qsd->qsd_exp_valid)
104                 imp = class_exp2cliimp(qsd->qsd_exp);
105         if (imp == NULL || imp->imp_invalid) {
106                 read_unlock(&qsd->qsd_lock);
107                 LQUOTA_DEBUG(lqe, "connection to master not ready");
108                 RETURN(-ENOTCONN);
109         }
110
111         /* In most case, reintegration must have been triggered (when enable
112          * quota or on OST start), however, in rare race condition (enabling
113          * quota when starting OSTs), we might miss triggering reintegration
114          * for some qqi.
115          *
116          * If the previous reintegration failed for some reason, we'll
117          * re-trigger it here as well. */
118         if (!qqi->qqi_glb_uptodate || !qqi->qqi_slv_uptodate) {
119                 read_unlock(&qsd->qsd_lock);
120                 LQUOTA_DEBUG(lqe, "not up-to-date, dropping request and "
121                              "kicking off reintegration");
122                 qsd_start_reint_thread(qqi);
123                 RETURN(-EINPROGRESS);
124         }
125
126         /* Fill the remote global lock handle, master will check this handle
127          * to see if the slave is sending request with stale lock */
128         lustre_handle_copy(lockh, &qqi->qqi_lockh);
129         read_unlock(&qsd->qsd_lock);
130
131         if (!lustre_handle_is_used(lockh))
132                 RETURN(-ENOLCK);
133
134         lock = ldlm_handle2lock(lockh);
135         if (lock == NULL)
136                 RETURN(-ENOLCK);
137
138         /* return remote lock handle to be packed in quota request */
139         lustre_handle_copy(lockh, &lock->l_remote_handle);
140         LDLM_LOCK_PUT(lock);
141
142         RETURN(0);
143 }
144
145 /**
146  * Check whether any quota space adjustment (pre-acquire/release/report) is
147  * needed for a given quota ID. If a non-null \a qbody is passed, then the
148  * \a qbody structure (qb_count/flags/usage) is filled with appropriate data
149  * to be packed in the quota request.
150  *
151  * \param lqe   - is the lquota entry for which we would like to adjust quota
152  *                space.
153  * \param qbody - is the quota body to fill, if not NULL.
154  *
155  * \retval true  - space adjustment is required and \a qbody is filled, if not
156  *                 NULL
157  * \retval false - no space adjustment required
158  */
159 static bool qsd_calc_adjust(struct lquota_entry *lqe, struct quota_body *qbody)
160 {
161         __u64   usage, granted;
162         ENTRY;
163
164         usage   = lqe->lqe_usage;
165         usage  += lqe->lqe_pending_write + lqe->lqe_waiting_write;
166         granted = lqe->lqe_granted;
167
168         if (qbody != NULL)
169                 qbody->qb_flags = 0;
170
171         if (!lqe->lqe_enforced) {
172                 /* quota not enforced any more for this ID */
173                 if (granted != 0) {
174                         /* release all quota space unconditionally */
175                         LQUOTA_DEBUG(lqe, "not enforced, releasing all space");
176                         if (qbody != NULL) {
177                                 qbody->qb_count = granted;
178                                 qbody->qb_flags = QUOTA_DQACQ_FL_REL;
179                         }
180                         RETURN(true);
181                 }
182                 RETURN(false);
183         }
184
185         if (!lustre_handle_is_used(&lqe->lqe_lockh)) {
186                 /* No valid per-ID lock
187                  * When reporting quota (during reintegration or on setquota
188                  * glimpse), we should release granted space if usage is 0.
189                  * Otherwise, if the usage is less than granted, we need to
190                  * acquire the per-ID lock to make sure the unused grant can be
191                  * reclaimed by per-ID lock glimpse. */
192                 if (usage == 0) {
193                         /* no on-disk usage and no outstanding activity, release
194                          * space */
195                         if (granted != 0) {
196                                 LQUOTA_DEBUG(lqe, "no usage, releasing all "
197                                              "space");
198                                 if (qbody != NULL) {
199                                         qbody->qb_count = granted;
200                                         qbody->qb_flags = QUOTA_DQACQ_FL_REL;
201                                 }
202                                 RETURN(true);
203                         }
204                         LQUOTA_DEBUG(lqe, "no usage + no granted, nothing to "
205                                      "do");
206                         RETURN(false);
207                 }
208
209                 if (lqe->lqe_usage < lqe->lqe_granted) {
210                         /* holding quota space w/o any lock, enqueue per-ID lock
211                          * again */
212                         LQUOTA_DEBUG(lqe, "(re)acquiring per-ID lock");
213                         if (qbody != NULL) {
214                                 qbody->qb_count = 0;
215                                 qbody->qb_flags = QUOTA_DQACQ_FL_ACQ;
216                         }
217                         RETURN(true);
218                 }
219
220                 if (lqe->lqe_usage > lqe->lqe_granted) {
221                         /* quota overrun, report usage */
222                         LQUOTA_DEBUG(lqe, "overrun, reporting usage");
223                         if (qbody != NULL) {
224                                 qbody->qb_usage = lqe->lqe_usage;
225                                 qbody->qb_flags = QUOTA_DQACQ_FL_REPORT;
226                         }
227                         RETURN(true);
228                 }
229                 LQUOTA_DEBUG(lqe, "granted matches usage, nothing to do");
230                 RETURN(false);
231         }
232
233         /* valid per-ID lock
234          * Apply good old quota qunit adjustment logic which has been around
235          * since lustre 1.4:
236          * 1. release spare quota space? */
237         if (granted > usage + lqe->lqe_qunit) {
238                 /* pre-release quota space */
239                 if (qbody == NULL)
240                         RETURN(true);
241                 qbody->qb_count = granted - usage;
242                 /* if usage == 0, release all granted space */
243                 if (usage) {
244                         /* try to keep one qunit of quota space */
245                         qbody->qb_count -= lqe->lqe_qunit;
246                         /* but don't release less than qtune to avoid releasing
247                          * space too often */
248                         if (qbody->qb_count < lqe->lqe_qtune)
249                                 qbody->qb_count = lqe->lqe_qtune;
250                 }
251                 qbody->qb_flags = QUOTA_DQACQ_FL_REL;
252                 RETURN(true);
253         }
254
255         /* 2. Any quota overrun? */
256         if (lqe->lqe_usage > lqe->lqe_granted) {
257                 /* we overconsumed quota space, we report usage in request so
258                  * that master can adjust it unconditionally */
259                 if (qbody == NULL)
260                         RETURN(true);
261                 qbody->qb_usage = lqe->lqe_usage;
262                 granted         = lqe->lqe_usage;
263                 qbody->qb_flags = QUOTA_DQACQ_FL_REPORT;
264         }
265
266         /* 3. Time to pre-acquire? */
267         if (!lqe->lqe_edquot && !lqe->lqe_nopreacq && usage > 0 &&
268             lqe->lqe_qunit != 0 && granted < usage + lqe->lqe_qtune) {
269                 /* To pre-acquire quota space, we report how much spare quota
270                  * space the slave currently owns, then the master will grant us
271                  * back how much we can pretend given the current state of
272                  * affairs */
273                 if (qbody == NULL)
274                         RETURN(true);
275                 if (granted <= usage)
276                         qbody->qb_count = 0;
277                 else
278                         qbody->qb_count = granted - usage;
279                 qbody->qb_flags |= QUOTA_DQACQ_FL_PREACQ;
280                 RETURN(true);
281         }
282
283         if (qbody != NULL)
284                 RETURN(qbody->qb_flags != 0);
285         else
286                 RETURN(false);
287 }
288
289 /**
290  * Helper function returning true when quota space need to be adjusted (some
291  * unused space should be free or pre-acquire) and false otherwise.
292  */
293 static inline bool qsd_adjust_needed(struct lquota_entry *lqe)
294 {
295         return qsd_calc_adjust(lqe, NULL);
296 }
297
298 /**
299  * Callback function called when an acquire/release request sent to the master
300  * is completed
301  */
302 static void qsd_req_completion(const struct lu_env *env,
303                                struct qsd_qtype_info *qqi,
304                                struct quota_body *reqbody,
305                                struct quota_body *repbody,
306                                struct lustre_handle *lockh,
307                                struct lquota_lvb *lvb,
308                                void *arg, int ret)
309 {
310         struct lquota_entry     *lqe = (struct lquota_entry *)arg;
311         struct qsd_thread_info  *qti;
312         int                      rc;
313         bool                     adjust = false, cancel = false;
314         ENTRY;
315
316         LASSERT(qqi != NULL && lqe != NULL);
317
318         /* environment passed by ptlrpcd is mostly used by CLIO and hasn't the
319          * DT tags set. */
320         rc = lu_env_refill_by_tags((struct lu_env *)env, LCT_DT_THREAD, 0);
321         if (rc) {
322                 LQUOTA_ERROR(lqe, "failed to refill environmnent %d", rc);
323                 lqe_write_lock(lqe);
324                 /* can't afford to adjust quota space with no suitable lu_env */
325                 GOTO(out_noadjust, rc);
326         }
327         qti = qsd_info(env);
328
329         lqe_write_lock(lqe);
330         LQUOTA_DEBUG(lqe, "DQACQ returned %d, flags:0x%x", ret,
331                      reqbody->qb_flags);
332
333         /* despite -EDQUOT & -EINPROGRESS errors, the master might still
334          * grant us back quota space to adjust quota overrun */
335         if (ret != 0 && ret != -EDQUOT && ret != -EINPROGRESS) {
336                 if (ret != -ETIMEDOUT && ret != -ENOTCONN &&
337                    ret != -ESHUTDOWN && ret != -EAGAIN)
338                         /* print errors only if return code is unexpected */
339                         LQUOTA_ERROR(lqe, "DQACQ failed with %d, flags:0x%x",
340                                      ret, reqbody->qb_flags);
341                 GOTO(out, ret);
342         }
343
344         /* Set the lqe_lockh */
345         if (lustre_handle_is_used(lockh) &&
346             !lustre_handle_equal(lockh, &lqe->lqe_lockh))
347                 lustre_handle_copy(&lqe->lqe_lockh, lockh);
348
349         /* If the replied qb_count is zero, it means master didn't process
350          * the DQACQ since the limit for this ID has been removed, so we
351          * should not update quota entry & slave index copy neither. */
352         if (repbody != NULL && repbody->qb_count != 0) {
353                 LQUOTA_DEBUG(lqe, "DQACQ qb_count:%llu", repbody->qb_count);
354
355                 if (req_is_rel(reqbody->qb_flags)) {
356                         if (lqe->lqe_granted < repbody->qb_count) {
357                                 LQUOTA_ERROR(lqe, "can't release more space "
358                                              "than owned %llu<%llu",
359                                              lqe->lqe_granted,
360                                              repbody->qb_count);
361                                 lqe->lqe_granted = 0;
362                         } else {
363                                 lqe->lqe_granted -= repbody->qb_count;
364                         }
365                         /* Cancel the per-ID lock initiatively when there
366                          * isn't any usage & grant, which can avoid master
367                          * sending glimpse unnecessarily to this slave on
368                          * quota revoking */
369                         if (!lqe->lqe_pending_write && !lqe->lqe_granted &&
370                             !lqe->lqe_waiting_write && !lqe->lqe_usage)
371                                 cancel = true;
372                 } else {
373                         lqe->lqe_granted += repbody->qb_count;
374                 }
375                 qti->qti_rec.lqr_slv_rec.qsr_granted = lqe->lqe_granted;
376                 lqe_write_unlock(lqe);
377
378                 /* Update the slave index file in the dedicated thread. So far,
379                  * We don't update the version of slave index copy on DQACQ.
380                  * No locking is necessary since nobody can change
381                  * lqe->lqe_granted while lqe->lqe_pending_req > 0 */
382                 qsd_upd_schedule(qqi, lqe, &lqe->lqe_id, &qti->qti_rec, 0,
383                                  false);
384                 lqe_write_lock(lqe);
385         }
386
387         /* extract information from lvb */
388         if (ret == 0 && lvb != NULL) {
389                 if (lvb->lvb_id_qunit != 0)
390                         qsd_set_qunit(lqe, lvb->lvb_id_qunit);
391                 qsd_set_edquot(lqe, !!(lvb->lvb_flags & LQUOTA_FL_EDQUOT));
392         } else if (repbody != NULL && repbody->qb_qunit != 0) {
393                 qsd_set_qunit(lqe, repbody->qb_qunit);
394         }
395
396         /* turn off pre-acquire if it failed with -EDQUOT. This is done to avoid
397          * flooding the master with acquire request. Pre-acquire will be turned
398          * on again as soon as qunit is modified */
399         if (req_is_preacq(reqbody->qb_flags) && ret == -EDQUOT)
400                 lqe->lqe_nopreacq = true;
401 out:
402         adjust = qsd_adjust_needed(lqe);
403         if (reqbody && req_is_acq(reqbody->qb_flags) && ret != -EDQUOT) {
404                 lqe->lqe_acq_rc = ret;
405                 lqe->lqe_acq_time = cfs_time_current_64();
406         }
407 out_noadjust:
408         qsd_request_exit(lqe);
409         lqe_write_unlock(lqe);
410
411         /* release reference on per-ID lock */
412         if (lustre_handle_is_used(lockh))
413                 ldlm_lock_decref(lockh, qsd_id_einfo.ei_mode);
414
415         if (cancel) {
416                 qsd_adjust_schedule(lqe, false, true);
417         } else if (adjust) {
418                 if (!ret || ret == -EDQUOT)
419                         qsd_adjust_schedule(lqe, false, false);
420                 else
421                         qsd_adjust_schedule(lqe, true, false);
422         }
423         lqe_putref(lqe);
424
425         if (lvb)
426                 OBD_FREE_PTR(lvb);
427         EXIT;
428 }
429
430 /**
431  * Try to consume local quota space.
432  *
433  * \param lqe   - is the qid entry to be processed
434  * \param space - is the amount of quota space needed to complete the operation
435  *
436  * \retval 0       - success
437  * \retval -EDQUOT - out of quota
438  * \retval -EAGAIN - need to acquire space from master
439  */
440 static int qsd_acquire_local(struct lquota_entry *lqe, __u64 space)
441 {
442         __u64   usage;
443         int     rc;
444         ENTRY;
445
446         if (!lqe->lqe_enforced)
447                 /* not enforced any more, we are good */
448                 RETURN(-ESRCH);
449
450         lqe_write_lock(lqe);
451         /* use latest usage */
452         usage = lqe->lqe_usage;
453         /* take pending write into account */
454         usage += lqe->lqe_pending_write;
455
456         if (space + usage <= lqe->lqe_granted - lqe->lqe_pending_rel) {
457                 /* Yay! we got enough space */
458                 lqe->lqe_pending_write += space;
459                 lqe->lqe_waiting_write -= space;
460                 rc = 0;
461         /* lqe_edquot flag is used to avoid flooding dqacq requests when
462          * the user is over quota, however, the lqe_edquot could be stale
463          * sometimes due to the race reply of dqacq vs. id lock glimpse
464          * (see LU-4505), so we revalidate it every 5 seconds. */
465         } else if (lqe->lqe_edquot &&
466                    cfs_time_before_64(cfs_time_shift_64(-5),
467                                       lqe->lqe_edquot_time)) {
468                 rc = -EDQUOT;
469         }else {
470                 rc = -EAGAIN;
471         }
472         lqe_write_unlock(lqe);
473
474         RETURN(rc);
475 }
476
477 /**
478  * Compute how much quota space should be acquire from the master based
479  * on how much is currently granted to this slave and pending/waiting
480  * operations.
481  *
482  * \param lqe - is the lquota entry for which we would like to adjust quota
483  *              space.
484  * \param qbody - is the quota body of the acquire request to fill
485  *
486  * \retval true  - space acquisition is needed and qbody is filled
487  * \retval false - no space acquisition required
488  */
489 static inline bool qsd_calc_acquire(struct lquota_entry *lqe,
490                                     struct quota_body *qbody)
491 {
492         __u64   usage, granted;
493
494         usage   = lqe->lqe_usage;
495         usage  += lqe->lqe_pending_write + lqe->lqe_waiting_write;
496         granted = lqe->lqe_granted;
497
498         qbody->qb_flags = 0;
499
500         /* if we overconsumed quota space, we report usage in request so that
501          * master can adjust it unconditionally */
502         if (lqe->lqe_usage > lqe->lqe_granted) {
503                 qbody->qb_usage = lqe->lqe_usage;
504                 qbody->qb_flags = QUOTA_DQACQ_FL_REPORT;
505                 granted = lqe->lqe_usage;
506         }
507
508         /* acquire as much as needed, but not more */
509         if (usage > granted) {
510                 qbody->qb_count  = usage - granted;
511                 qbody->qb_flags |= QUOTA_DQACQ_FL_ACQ;
512         }
513
514         return qbody->qb_flags != 0;
515 }
516
517 /**
518  * Acquire quota space from master.
519  * There are at most 1 in-flight dqacq/dqrel.
520  *
521  * \param env    - the environment passed by the caller
522  * \param lqe    - is the qid entry to be processed
523  *
524  * \retval 0            - success
525  * \retval -EDQUOT      - out of quota
526  * \retval -EINPROGRESS - inform client to retry write/create
527  * \retval -EBUSY       - already a quota request in flight
528  * \retval -ve          - other appropriate errors
529  */
530 static int qsd_acquire_remote(const struct lu_env *env,
531                               struct lquota_entry *lqe)
532 {
533         struct qsd_thread_info  *qti = qsd_info(env);
534         struct quota_body       *qbody = &qti->qti_body;
535         struct qsd_instance     *qsd;
536         struct qsd_qtype_info   *qqi;
537         int                      rc;
538         ENTRY;
539
540         memset(qbody, 0, sizeof(*qbody));
541         rc = qsd_ready(lqe, &qbody->qb_glb_lockh);
542         if (rc)
543                 RETURN(rc);
544
545         qqi = lqe2qqi(lqe);
546         qsd = qqi->qqi_qsd;
547
548         lqe_write_lock(lqe);
549
550         /* is quota really enforced for this id? */
551         if (!lqe->lqe_enforced) {
552                 lqe_write_unlock(lqe);
553                 LQUOTA_DEBUG(lqe, "quota not enforced any more");
554                 RETURN(0);
555         }
556
557         /* fill qb_count & qb_flags */
558         if (!qsd_calc_acquire(lqe, qbody)) {
559                 lqe_write_unlock(lqe);
560                 LQUOTA_DEBUG(lqe, "No acquire required");
561                 RETURN(0);
562         }
563
564         /* check whether an acquire request completed recently */
565         if (lqe->lqe_acq_rc != 0 &&
566             cfs_time_before_64(cfs_time_shift_64(-1), lqe->lqe_acq_time)) {
567                 lqe_write_unlock(lqe);
568                 LQUOTA_DEBUG(lqe, "using cached return code %d", lqe->lqe_acq_rc);
569                 RETURN(lqe->lqe_acq_rc);
570         }
571
572         /* only 1 quota request in flight for a given ID is allowed */
573         rc = qsd_request_enter(lqe);
574         if (rc) {
575                 lqe_write_unlock(lqe);
576                 RETURN(rc);
577         }
578
579         lustre_handle_copy(&qti->qti_lockh, &lqe->lqe_lockh);
580         lqe_write_unlock(lqe);
581
582         /* hold a refcount until completion */
583         lqe_getref(lqe);
584
585         /* fill other quota body fields */
586         qbody->qb_fid = qqi->qqi_fid;
587         qbody->qb_id  = lqe->lqe_id;
588
589         /* check whether we already own a valid lock for this ID */
590         rc = qsd_id_lock_match(&qti->qti_lockh, &qbody->qb_lockh);
591         if (rc) {
592                 struct lquota_lvb *lvb;
593
594                 OBD_ALLOC_PTR(lvb);
595                 if (lvb == NULL) {
596                         rc = -ENOMEM;
597                         qsd_req_completion(env, qqi, qbody, NULL,
598                                            &qti->qti_lockh, NULL, lqe, rc);
599                         RETURN(rc);
600                 }
601                 /* no lock found, should use intent */
602                 rc = qsd_intent_lock(env, qsd->qsd_exp, qbody, true,
603                                      IT_QUOTA_DQACQ, qsd_req_completion,
604                                      qqi, lvb, (void *)lqe);
605         } else {
606                 /* lock found, should use regular dqacq */
607                 rc = qsd_send_dqacq(env, qsd->qsd_exp, qbody, true,
608                                     qsd_req_completion, qqi, &qti->qti_lockh,
609                                     lqe);
610         }
611
612         /* the completion function will be called by qsd_send_dqacq or
613          * qsd_intent_lock */
614         RETURN(rc);
615 }
616
617 /**
618  * Acquire \a space of quota space in order to complete an operation.
619  * Try to consume local quota space first and send acquire request to quota
620  * master if required.
621  *
622  * \param env   - the environment passed by the caller
623  * \param lqe   - is the qid entry to be processed
624  * \param space - is the amount of quota required for the operation
625  * \param ret   - is the return code (-EDQUOT, -EINPROGRESS, ...)
626  *
627  * \retval true  - exit from l_wait_event and real return value in \a ret
628  * \retval false - continue waiting
629  */
630 static bool qsd_acquire(const struct lu_env *env, struct lquota_entry *lqe,
631                         long long space, int *ret)
632 {
633         int rc = 0, count;
634         ENTRY;
635
636         for (count = 0; rc == 0; count++) {
637                 LQUOTA_DEBUG(lqe, "acquiring:%lld count=%d", space, count);
638
639                 if (lqe2qqi(lqe)->qqi_qsd->qsd_stopping) {
640                         rc = -EINPROGRESS;
641                         break;
642                 }
643
644                 /* refresh disk usage */
645                 rc = qsd_refresh_usage(env, lqe);
646                 if (rc)
647                         break;
648
649                 /* try to consume local quota space first */
650                 rc = qsd_acquire_local(lqe, space);
651                 if (rc != -EAGAIN)
652                         /* rc == 0, Wouhou! enough local quota space
653                          * rc < 0, something bad happened */
654                          break;
655
656                 /* need to acquire more quota space from master */
657                 rc = qsd_acquire_remote(env, lqe);
658         }
659
660         if (rc == -EBUSY)
661                 /* already a request in flight, continue waiting */
662                 RETURN(false);
663         *ret = rc;
664         RETURN(true); /* exit from l_wait_event */
665 }
666
667 /**
668  * Quota enforcement handler. If local quota can satisfy this operation,
669  * return success, otherwise, acquire more quota from master.
670  * (for write operation, if master isn't available at this moment, return
671  * -EINPROGRESS to inform client to retry the write)
672  *
673  * \param env   - the environment passed by the caller
674  * \param qsd   - is the qsd instance associated with the device in charge
675  *                of the operation.
676  * \param qid   - is the qid information attached in the transaction handle
677  * \param space - is the space required by the operation
678  * \param flags - if the operation is write, return caller no user/group
679  *                and sync commit flags
680  *
681  * \retval 0            - success
682  * \retval -EDQUOT      - out of quota
683  * \retval -EINPROGRESS - inform client to retry write
684  * \retval -ve          - other appropriate errors
685  */
686 static int qsd_op_begin0(const struct lu_env *env, struct qsd_qtype_info *qqi,
687                          struct lquota_id_info *qid, long long space,
688                          int *flags)
689 {
690         struct lquota_entry     *lqe;
691         int                      rc, ret = -EINPROGRESS;
692         struct l_wait_info       lwi;
693         ENTRY;
694
695         if (qid->lqi_qentry != NULL) {
696                 /* we already had to deal with this id for this transaction */
697                 lqe = qid->lqi_qentry;
698                 if (!lqe->lqe_enforced)
699                         RETURN(0);
700         } else {
701                 /* look up lquota entry associated with qid */
702                 lqe = lqe_locate(env, qqi->qqi_site, &qid->lqi_id);
703                 if (IS_ERR(lqe))
704                         RETURN(PTR_ERR(lqe));
705                 if (!lqe->lqe_enforced) {
706                         lqe_putref(lqe);
707                         RETURN(0);
708                 }
709                 qid->lqi_qentry = lqe;
710                 /* lqe will be released in qsd_op_end() */
711         }
712
713         if (space <= 0) {
714                 /* when space is negative or null, we don't need to consume
715                  * quota space. That said, we still want to perform space
716                  * adjustments in qsd_op_end, so we return here, but with
717                  * a reference on the lqe */
718                 if (flags != NULL) {
719                         rc = qsd_refresh_usage(env, lqe);
720                         GOTO(out_flags, rc);
721                 }
722                 RETURN(0);
723         }
724
725         LQUOTA_DEBUG(lqe, "op_begin space:%lld", space);
726
727         lqe_write_lock(lqe);
728         lqe->lqe_waiting_write += space;
729         lqe_write_unlock(lqe);
730
731         /* acquire quota space for the operation, cap overall wait time to
732          * prevent a service thread from being stuck for too long */
733         lwi = LWI_TIMEOUT(cfs_time_seconds(qsd_wait_timeout(qqi->qqi_qsd)),
734                           NULL, NULL);
735         rc = l_wait_event(lqe->lqe_waiters, qsd_acquire(env, lqe, space, &ret),
736                           &lwi);
737
738         if (rc == 0 && ret == 0) {
739                 qid->lqi_space += space;
740         } else {
741                 if (rc == 0)
742                         rc = ret;
743
744                 LQUOTA_DEBUG(lqe, "acquire quota failed:%d", rc);
745
746                 lqe_write_lock(lqe);
747                 lqe->lqe_waiting_write -= space;
748
749                 if (flags && lqe->lqe_pending_write != 0)
750                         /* Inform OSD layer that there are pending writes.
751                          * It might want to retry after a sync if appropriate */
752                          *flags |= QUOTA_FL_SYNC;
753                 lqe_write_unlock(lqe);
754
755                 /* convert recoverable error into -EINPROGRESS, client will
756                  * retry */
757                 if (rc == -ETIMEDOUT || rc == -ENOTCONN || rc == -ENOLCK ||
758                     rc == -EAGAIN || rc == -EINTR) {
759                         rc = -EINPROGRESS;
760                 } else if (rc == -ESRCH) {
761                         rc = 0;
762                         LQUOTA_ERROR(lqe, "ID isn't enforced on master, it "
763                                      "probably due to a legeal race, if this "
764                                      "message is showing up constantly, there "
765                                      "could be some inconsistence between "
766                                      "master & slave, and quota reintegration "
767                                      "needs be re-triggered.");
768                 }
769         }
770
771         if (flags != NULL) {
772 out_flags:
773                 LASSERT(qid->lqi_is_blk);
774                 if (rc != 0) {
775                         *flags |= LQUOTA_OVER_FL(qqi->qqi_qtype);
776                 } else {
777                         __u64   usage;
778
779                         lqe_read_lock(lqe);
780                         usage  = lqe->lqe_usage;
781                         usage += lqe->lqe_pending_write;
782                         usage += lqe->lqe_waiting_write;
783                         usage += qqi->qqi_qsd->qsd_sync_threshold;
784
785                         /* if we should notify client to start sync write */
786                         if (usage >= lqe->lqe_granted - lqe->lqe_pending_rel)
787                                 *flags |= LQUOTA_OVER_FL(qqi->qqi_qtype);
788                         else
789                                 *flags &= ~LQUOTA_OVER_FL(qqi->qqi_qtype);
790                         lqe_read_unlock(lqe);
791                 }
792         }
793         RETURN(rc);
794 }
795
796 /**
797  * helper function comparing two lquota_id_info structures
798  */
799 static inline bool qid_equal(struct lquota_id_info *q1,
800                              struct lquota_id_info *q2)
801 {
802         if (q1->lqi_type != q2->lqi_type)
803                 return false;
804         return (q1->lqi_id.qid_uid == q2->lqi_id.qid_uid) ? true : false;
805 }
806
807 /**
808  * Enforce quota, it's called in the declaration of each operation.
809  * qsd_op_end() will then be called later once all the operations have been
810  * completed in order to release/adjust the quota space.
811  *
812  * \param env   - the environment passed by the caller
813  * \param qsd   - is the qsd instance associated with the device in charge of
814  *                the operation.
815  * \param trans - is the quota transaction information
816  * \param qi    - qid & space required by current operation
817  * \param flags - if the operation is write, return caller no user/group and
818  *                sync commit flags
819  *
820  * \retval 0            - success
821  * \retval -EDQUOT      - out of quota
822  * \retval -EINPROGRESS - inform client to retry write
823  * \retval -ve          - other appropriate errors
824  */
825 int qsd_op_begin(const struct lu_env *env, struct qsd_instance *qsd,
826                  struct lquota_trans *trans, struct lquota_id_info *qi,
827                  int *flags)
828 {
829         int     i, rc;
830         bool    found = false;
831         ENTRY;
832
833         if (unlikely(qsd == NULL))
834                 RETURN(0);
835
836         /* We don't enforce quota until the qsd_instance is started */
837         read_lock(&qsd->qsd_lock);
838         if (!qsd->qsd_started) {
839                 read_unlock(&qsd->qsd_lock);
840                 RETURN(0);
841         }
842         read_unlock(&qsd->qsd_lock);
843
844         /* ignore block quota on MDTs, ignore inode quota on OSTs */
845         if ((!qsd->qsd_is_md && !qi->lqi_is_blk) ||
846             (qsd->qsd_is_md && qi->lqi_is_blk))
847                 RETURN(0);
848
849         /* ignore quota enforcement request when:
850          *    - quota isn't enforced for this quota type
851          * or - the user/group is root
852          * or - quota accounting isn't enabled */
853         if (!qsd_type_enabled(qsd, qi->lqi_type) || qi->lqi_id.qid_uid == 0 ||
854             qsd->qsd_acct_failed)
855                 RETURN(0);
856
857         LASSERTF(trans->lqt_id_cnt <= QUOTA_MAX_TRANSIDS, "id_cnt=%d\n",
858                  trans->lqt_id_cnt);
859         /* check whether we already allocated a slot for this id */
860         for (i = 0; i < trans->lqt_id_cnt; i++) {
861                 if (qid_equal(qi, &trans->lqt_ids[i])) {
862                         found = true;
863                         /* make sure we are not mixing inodes & blocks */
864                         LASSERT(trans->lqt_ids[i].lqi_is_blk == qi->lqi_is_blk);
865                         break;
866                 }
867         }
868
869         if (!found) {
870                 if (unlikely(i >= QUOTA_MAX_TRANSIDS)) {
871                         CERROR("%s: more than %d qids enforced for a "
872                                "transaction?\n", qsd->qsd_svname, i);
873                         RETURN(-EINVAL);
874                 }
875
876                 /* fill new slot */
877                 trans->lqt_ids[i].lqi_id     = qi->lqi_id;
878                 trans->lqt_ids[i].lqi_type   = qi->lqi_type;
879                 trans->lqt_ids[i].lqi_is_blk = qi->lqi_is_blk;
880                 trans->lqt_id_cnt++;
881         }
882
883         /* manage quota enforcement for this ID */
884         rc = qsd_op_begin0(env, qsd->qsd_type_array[qi->lqi_type],
885                            &trans->lqt_ids[i], qi->lqi_space, flags);
886         RETURN(rc);
887 }
888 EXPORT_SYMBOL(qsd_op_begin);
889
890 /**
891  * Adjust quota space (by acquiring or releasing) hold by the quota slave.
892  * This function is called after each quota request completion and during
893  * reintegration in order to report usage or re-acquire quota locks.
894  * Space adjustment is aborted if there is already a quota request in flight
895  * for this ID.
896  *
897  * \param env    - the environment passed by the caller
898  * \param lqe    - is the qid entry to be processed
899  *
900  * \retval 0 on success, appropriate errors on failure
901  */
902 int qsd_adjust(const struct lu_env *env, struct lquota_entry *lqe)
903 {
904         struct qsd_thread_info  *qti = qsd_info(env);
905         struct quota_body       *qbody = &qti->qti_body;
906         struct qsd_instance     *qsd;
907         struct qsd_qtype_info   *qqi;
908         int                      rc;
909         bool                     intent = false;
910         ENTRY;
911
912         memset(qbody, 0, sizeof(*qbody));
913         rc = qsd_ready(lqe, &qbody->qb_glb_lockh);
914         if (rc) {
915                 /* add to adjust list again to trigger adjustment later when
916                  * slave is ready */
917                 LQUOTA_DEBUG(lqe, "delaying adjustment since qsd isn't ready");
918                 qsd_adjust_schedule(lqe, true, false);
919                 RETURN(0);
920         }
921
922         qqi = lqe2qqi(lqe);
923         qsd = qqi->qqi_qsd;
924
925         lqe_write_lock(lqe);
926
927         /* fill qb_count & qb_flags */
928         if (!qsd_calc_adjust(lqe, qbody)) {
929                 lqe_write_unlock(lqe);
930                 LQUOTA_DEBUG(lqe, "no adjustment required");
931                 RETURN(0);
932         }
933
934         /* only 1 quota request in flight for a given ID is allowed */
935         rc = qsd_request_enter(lqe);
936         if (rc) {
937                 /* already a request in flight, space adjustment will be run
938                  * again on request completion */
939                 lqe_write_unlock(lqe);
940                 RETURN(0);
941         }
942
943         if (req_is_rel(qbody->qb_flags))
944                 lqe->lqe_pending_rel = qbody->qb_count;
945         lustre_handle_copy(&qti->qti_lockh, &lqe->lqe_lockh);
946         lqe_write_unlock(lqe);
947
948         /* hold a refcount until completion */
949         lqe_getref(lqe);
950
951         /* fill other quota body fields */
952         qbody->qb_fid = qqi->qqi_fid;
953         qbody->qb_id  = lqe->lqe_id;
954
955         if (req_is_acq(qbody->qb_flags) || req_is_preacq(qbody->qb_flags)) {
956                 /* check whether we own a valid lock for this ID */
957                 rc = qsd_id_lock_match(&qti->qti_lockh, &qbody->qb_lockh);
958                 if (rc) {
959                         memset(&qti->qti_lockh, 0, sizeof(qti->qti_lockh));
960                         if (req_is_preacq(qbody->qb_flags)) {
961                                 if (req_has_rep(qbody->qb_flags))
962                                         /* still want to report usage */
963                                         qbody->qb_flags = QUOTA_DQACQ_FL_REPORT;
964                                 else
965                                         /* no pre-acquire if no per-ID lock */
966                                         GOTO(out, rc = -ENOLCK);
967                         } else {
968                                 /* no lock found, should use intent */
969                                 intent = true;
970                         }
971                 } else if (req_is_acq(qbody->qb_flags) &&
972                            qbody->qb_count == 0) {
973                         /* found cached lock, no need to acquire */
974                         GOTO(out, rc = 0);
975                 }
976         } else {
977                 /* release and report don't need a per-ID lock */
978                 memset(&qti->qti_lockh, 0, sizeof(qti->qti_lockh));
979         }
980
981         if (!intent) {
982                 rc = qsd_send_dqacq(env, qsd->qsd_exp, qbody, false,
983                                     qsd_req_completion, qqi, &qti->qti_lockh,
984                                     lqe);
985         } else {
986                 struct lquota_lvb *lvb;
987
988                 OBD_ALLOC_PTR(lvb);
989                 if (lvb == NULL)
990                         GOTO(out, rc = -ENOMEM);
991
992                 rc = qsd_intent_lock(env, qsd->qsd_exp, qbody, false,
993                                      IT_QUOTA_DQACQ, qsd_req_completion,
994                                      qqi, lvb, (void *)lqe);
995         }
996         /* the completion function will be called by qsd_send_dqacq or
997          * qsd_intent_lock */
998         RETURN(rc);
999 out:
1000         qsd_req_completion(env, qqi, qbody, NULL, &qti->qti_lockh, NULL, lqe,
1001                            rc);
1002         return rc;
1003 }
1004
1005 /**
1006  * Post quota operation, pre-acquire/release quota from master.
1007  *
1008  * \param  env  - the environment passed by the caller
1009  * \param  qsd  - is the qsd instance attached to the OSD device which
1010  *                is handling the operation.
1011  * \param  qqi  - is the qsd_qtype_info structure associated with the quota ID
1012  *                subject to the operation
1013  * \param  qid  - stores information related to his ID for the operation
1014  *                which has just completed
1015  *
1016  * \retval 0    - success
1017  * \retval -ve  - failure
1018  */
1019 static void qsd_op_end0(const struct lu_env *env, struct qsd_qtype_info *qqi,
1020                         struct lquota_id_info *qid)
1021 {
1022         struct lquota_entry     *lqe;
1023         bool                     adjust;
1024         ENTRY;
1025
1026         lqe = qid->lqi_qentry;
1027         if (lqe == NULL)
1028                 RETURN_EXIT;
1029         qid->lqi_qentry = NULL;
1030
1031         /* refresh cached usage if a suitable environment is passed */
1032         if (env != NULL)
1033                 qsd_refresh_usage(env, lqe);
1034
1035         lqe_write_lock(lqe);
1036         if (qid->lqi_space > 0)
1037                 lqe->lqe_pending_write -= qid->lqi_space;
1038         if (env != NULL)
1039                 adjust = qsd_adjust_needed(lqe);
1040         else
1041                 adjust = true;
1042         lqe_write_unlock(lqe);
1043
1044         if (adjust) {
1045                 /* pre-acquire/release quota space is needed */
1046                 if (env != NULL)
1047                         qsd_adjust(env, lqe);
1048                 else
1049                         /* no suitable environment, handle adjustment in
1050                          * separate thread context */
1051                         qsd_adjust_schedule(lqe, false, false);
1052         }
1053         lqe_putref(lqe);
1054         EXIT;
1055 }
1056
1057 /**
1058  * Post quota operation. It's called after each operation transaction stopped.
1059  *
1060  * \param  env   - the environment passed by the caller
1061  * \param  qsd   - is the qsd instance associated with device which is handling
1062  *                 the operation.
1063  * \param  qids  - all qids information attached in the transaction handle
1064  * \param  count - is the number of qid entries in the qids array.
1065  *
1066  * \retval 0     - success
1067  * \retval -ve   - failure
1068  */
1069 void qsd_op_end(const struct lu_env *env, struct qsd_instance *qsd,
1070                 struct lquota_trans *trans)
1071 {
1072         int i;
1073         ENTRY;
1074
1075         if (unlikely(qsd == NULL))
1076                 RETURN_EXIT;
1077
1078         /* We don't enforce quota until the qsd_instance is started */
1079         read_lock(&qsd->qsd_lock);
1080         if (!qsd->qsd_started) {
1081                 read_unlock(&qsd->qsd_lock);
1082                 RETURN_EXIT;
1083         }
1084         read_unlock(&qsd->qsd_lock);
1085
1086         LASSERT(trans != NULL);
1087
1088         for (i = 0; i < trans->lqt_id_cnt; i++) {
1089                 struct qsd_qtype_info *qqi;
1090
1091                 if (trans->lqt_ids[i].lqi_qentry == NULL)
1092                         continue;
1093
1094                 qqi = qsd->qsd_type_array[trans->lqt_ids[i].lqi_type];
1095                 qsd_op_end0(env, qqi, &trans->lqt_ids[i]);
1096         }
1097
1098         /* reset id_count to 0 so that a second accidental call to qsd_op_end()
1099          * does not result in failure */
1100         trans->lqt_id_cnt = 0;
1101         EXIT;
1102 }
1103 EXPORT_SYMBOL(qsd_op_end);
1104
1105 /**
1106  * Trigger pre-acquire/release if necessary.
1107  * It's only used by ldiskfs osd so far. When unlink a file in ldiskfs, the
1108  * quota accounting isn't updated when the transaction stopped. Instead, it'll
1109  * be updated on the final iput, so qsd_op_adjust() will be called then (in
1110  * osd_object_delete()) to trigger quota release if necessary.
1111  *
1112  * \param env - the environment passed by the caller
1113  * \param qsd - is the qsd instance associated with the device in charge
1114  *              of the operation.
1115  * \param qid - is the lquota ID of the user/group for which to trigger
1116  *              quota space adjustment
1117  * \param qtype - is the quota type (USRQUOTA or GRPQUOTA)
1118  */
1119 void qsd_op_adjust(const struct lu_env *env, struct qsd_instance *qsd,
1120                    union lquota_id *qid, int qtype)
1121 {
1122         struct lquota_entry    *lqe;
1123         struct qsd_qtype_info  *qqi;
1124         bool                    adjust;
1125         ENTRY;
1126
1127         if (unlikely(qsd == NULL))
1128                 RETURN_EXIT;
1129
1130         /* We don't enforce quota until the qsd_instance is started */
1131         read_lock(&qsd->qsd_lock);
1132         if (!qsd->qsd_started) {
1133                 read_unlock(&qsd->qsd_lock);
1134                 RETURN_EXIT;
1135         }
1136         read_unlock(&qsd->qsd_lock);
1137
1138         qqi = qsd->qsd_type_array[qtype];
1139         LASSERT(qqi);
1140
1141         if (!qsd_type_enabled(qsd, qtype) || qqi->qqi_acct_obj == NULL ||
1142             qid->qid_uid == 0)
1143                 RETURN_EXIT;
1144
1145         read_lock(&qsd->qsd_lock);
1146         if (!qsd->qsd_started) {
1147                 read_unlock(&qsd->qsd_lock);
1148                 RETURN_EXIT;
1149         }
1150         read_unlock(&qsd->qsd_lock);
1151
1152         lqe = lqe_locate(env, qqi->qqi_site, qid);
1153         if (IS_ERR(lqe)) {
1154                 CERROR("%s: fail to locate lqe for id:%llu, type:%d\n",
1155                        qsd->qsd_svname, qid->qid_uid, qtype);
1156                 RETURN_EXIT;
1157         }
1158
1159         qsd_refresh_usage(env, lqe);
1160
1161         lqe_read_lock(lqe);
1162         adjust = qsd_adjust_needed(lqe);
1163         lqe_read_unlock(lqe);
1164
1165         if (adjust)
1166                 qsd_adjust(env, lqe);
1167
1168         lqe_putref(lqe);
1169         EXIT;
1170 }
1171 EXPORT_SYMBOL(qsd_op_adjust);