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TOMOYO Linux Cross Reference
Linux/fs/gfs2/quota.c

Version: ~ [ linux-5.2 ] ~ [ linux-5.1.16 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.57 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.132 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.184 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.184 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.69 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.39.4 ] ~ [ linux-2.6.38.8 ] ~ [ linux-2.6.37.6 ] ~ [ linux-2.6.36.4 ] ~ [ linux-2.6.35.14 ] ~ [ linux-2.6.34.15 ] ~ [ linux-2.6.33.20 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
  3  * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
  4  *
  5  * This copyrighted material is made available to anyone wishing to use,
  6  * modify, copy, or redistribute it subject to the terms and conditions
  7  * of the GNU General Public License version 2.
  8  */
  9 
 10 /*
 11  * Quota change tags are associated with each transaction that allocates or
 12  * deallocates space.  Those changes are accumulated locally to each node (in a
 13  * per-node file) and then are periodically synced to the quota file.  This
 14  * avoids the bottleneck of constantly touching the quota file, but introduces
 15  * fuzziness in the current usage value of IDs that are being used on different
 16  * nodes in the cluster simultaneously.  So, it is possible for a user on
 17  * multiple nodes to overrun their quota, but that overrun is controlable.
 18  * Since quota tags are part of transactions, there is no need for a quota check
 19  * program to be run on node crashes or anything like that.
 20  *
 21  * There are couple of knobs that let the administrator manage the quota
 22  * fuzziness.  "quota_quantum" sets the maximum time a quota change can be
 23  * sitting on one node before being synced to the quota file.  (The default is
 24  * 60 seconds.)  Another knob, "quota_scale" controls how quickly the frequency
 25  * of quota file syncs increases as the user moves closer to their limit.  The
 26  * more frequent the syncs, the more accurate the quota enforcement, but that
 27  * means that there is more contention between the nodes for the quota file.
 28  * The default value is one.  This sets the maximum theoretical quota overrun
 29  * (with infinite node with infinite bandwidth) to twice the user's limit.  (In
 30  * practice, the maximum overrun you see should be much less.)  A "quota_scale"
 31  * number greater than one makes quota syncs more frequent and reduces the
 32  * maximum overrun.  Numbers less than one (but greater than zero) make quota
 33  * syncs less frequent.
 34  *
 35  * GFS quotas also use per-ID Lock Value Blocks (LVBs) to cache the contents of
 36  * the quota file, so it is not being constantly read.
 37  */
 38 
 39 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 40 
 41 #include <linux/sched.h>
 42 #include <linux/slab.h>
 43 #include <linux/mm.h>
 44 #include <linux/spinlock.h>
 45 #include <linux/completion.h>
 46 #include <linux/buffer_head.h>
 47 #include <linux/sort.h>
 48 #include <linux/fs.h>
 49 #include <linux/bio.h>
 50 #include <linux/gfs2_ondisk.h>
 51 #include <linux/kthread.h>
 52 #include <linux/freezer.h>
 53 #include <linux/quota.h>
 54 #include <linux/dqblk_xfs.h>
 55 #include <linux/lockref.h>
 56 #include <linux/list_lru.h>
 57 #include <linux/rcupdate.h>
 58 #include <linux/rculist_bl.h>
 59 #include <linux/bit_spinlock.h>
 60 #include <linux/jhash.h>
 61 #include <linux/vmalloc.h>
 62 
 63 #include "gfs2.h"
 64 #include "incore.h"
 65 #include "bmap.h"
 66 #include "glock.h"
 67 #include "glops.h"
 68 #include "log.h"
 69 #include "meta_io.h"
 70 #include "quota.h"
 71 #include "rgrp.h"
 72 #include "super.h"
 73 #include "trans.h"
 74 #include "inode.h"
 75 #include "util.h"
 76 
 77 #define GFS2_QD_HASH_SHIFT      12
 78 #define GFS2_QD_HASH_SIZE       (1 << GFS2_QD_HASH_SHIFT)
 79 #define GFS2_QD_HASH_MASK       (GFS2_QD_HASH_SIZE - 1)
 80 
 81 /* Lock order: qd_lock -> bucket lock -> qd->lockref.lock -> lru lock */
 82 /*                     -> sd_bitmap_lock                              */
 83 static DEFINE_SPINLOCK(qd_lock);
 84 struct list_lru gfs2_qd_lru;
 85 
 86 static struct hlist_bl_head qd_hash_table[GFS2_QD_HASH_SIZE];
 87 
 88 static unsigned int gfs2_qd_hash(const struct gfs2_sbd *sdp,
 89                                  const struct kqid qid)
 90 {
 91         unsigned int h;
 92 
 93         h = jhash(&sdp, sizeof(struct gfs2_sbd *), 0);
 94         h = jhash(&qid, sizeof(struct kqid), h);
 95 
 96         return h & GFS2_QD_HASH_MASK;
 97 }
 98 
 99 static inline void spin_lock_bucket(unsigned int hash)
100 {
101         hlist_bl_lock(&qd_hash_table[hash]);
102 }
103 
104 static inline void spin_unlock_bucket(unsigned int hash)
105 {
106         hlist_bl_unlock(&qd_hash_table[hash]);
107 }
108 
109 static void gfs2_qd_dealloc(struct rcu_head *rcu)
110 {
111         struct gfs2_quota_data *qd = container_of(rcu, struct gfs2_quota_data, qd_rcu);
112         kmem_cache_free(gfs2_quotad_cachep, qd);
113 }
114 
115 static void gfs2_qd_dispose(struct list_head *list)
116 {
117         struct gfs2_quota_data *qd;
118         struct gfs2_sbd *sdp;
119 
120         while (!list_empty(list)) {
121                 qd = list_entry(list->next, struct gfs2_quota_data, qd_lru);
122                 sdp = qd->qd_gl->gl_name.ln_sbd;
123 
124                 list_del(&qd->qd_lru);
125 
126                 /* Free from the filesystem-specific list */
127                 spin_lock(&qd_lock);
128                 list_del(&qd->qd_list);
129                 spin_unlock(&qd_lock);
130 
131                 spin_lock_bucket(qd->qd_hash);
132                 hlist_bl_del_rcu(&qd->qd_hlist);
133                 spin_unlock_bucket(qd->qd_hash);
134 
135                 gfs2_assert_warn(sdp, !qd->qd_change);
136                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
137                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
138 
139                 gfs2_glock_put(qd->qd_gl);
140                 atomic_dec(&sdp->sd_quota_count);
141 
142                 /* Delete it from the common reclaim list */
143                 call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
144         }
145 }
146 
147 
148 static enum lru_status gfs2_qd_isolate(struct list_head *item,
149                 struct list_lru_one *lru, spinlock_t *lru_lock, void *arg)
150 {
151         struct list_head *dispose = arg;
152         struct gfs2_quota_data *qd = list_entry(item, struct gfs2_quota_data, qd_lru);
153 
154         if (!spin_trylock(&qd->qd_lockref.lock))
155                 return LRU_SKIP;
156 
157         if (qd->qd_lockref.count == 0) {
158                 lockref_mark_dead(&qd->qd_lockref);
159                 list_lru_isolate_move(lru, &qd->qd_lru, dispose);
160         }
161 
162         spin_unlock(&qd->qd_lockref.lock);
163         return LRU_REMOVED;
164 }
165 
166 static unsigned long gfs2_qd_shrink_scan(struct shrinker *shrink,
167                                          struct shrink_control *sc)
168 {
169         LIST_HEAD(dispose);
170         unsigned long freed;
171 
172         if (!(sc->gfp_mask & __GFP_FS))
173                 return SHRINK_STOP;
174 
175         freed = list_lru_shrink_walk(&gfs2_qd_lru, sc,
176                                      gfs2_qd_isolate, &dispose);
177 
178         gfs2_qd_dispose(&dispose);
179 
180         return freed;
181 }
182 
183 static unsigned long gfs2_qd_shrink_count(struct shrinker *shrink,
184                                           struct shrink_control *sc)
185 {
186         return vfs_pressure_ratio(list_lru_shrink_count(&gfs2_qd_lru, sc));
187 }
188 
189 struct shrinker gfs2_qd_shrinker = {
190         .count_objects = gfs2_qd_shrink_count,
191         .scan_objects = gfs2_qd_shrink_scan,
192         .seeks = DEFAULT_SEEKS,
193         .flags = SHRINKER_NUMA_AWARE,
194 };
195 
196 
197 static u64 qd2index(struct gfs2_quota_data *qd)
198 {
199         struct kqid qid = qd->qd_id;
200         return (2 * (u64)from_kqid(&init_user_ns, qid)) +
201                 ((qid.type == USRQUOTA) ? 0 : 1);
202 }
203 
204 static u64 qd2offset(struct gfs2_quota_data *qd)
205 {
206         u64 offset;
207 
208         offset = qd2index(qd);
209         offset *= sizeof(struct gfs2_quota);
210 
211         return offset;
212 }
213 
214 static struct gfs2_quota_data *qd_alloc(unsigned hash, struct gfs2_sbd *sdp, struct kqid qid)
215 {
216         struct gfs2_quota_data *qd;
217         int error;
218 
219         qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
220         if (!qd)
221                 return NULL;
222 
223         qd->qd_sbd = sdp;
224         qd->qd_lockref.count = 1;
225         spin_lock_init(&qd->qd_lockref.lock);
226         qd->qd_id = qid;
227         qd->qd_slot = -1;
228         INIT_LIST_HEAD(&qd->qd_lru);
229         qd->qd_hash = hash;
230 
231         error = gfs2_glock_get(sdp, qd2index(qd),
232                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
233         if (error)
234                 goto fail;
235 
236         return qd;
237 
238 fail:
239         kmem_cache_free(gfs2_quotad_cachep, qd);
240         return NULL;
241 }
242 
243 static struct gfs2_quota_data *gfs2_qd_search_bucket(unsigned int hash,
244                                                      const struct gfs2_sbd *sdp,
245                                                      struct kqid qid)
246 {
247         struct gfs2_quota_data *qd;
248         struct hlist_bl_node *h;
249 
250         hlist_bl_for_each_entry_rcu(qd, h, &qd_hash_table[hash], qd_hlist) {
251                 if (!qid_eq(qd->qd_id, qid))
252                         continue;
253                 if (qd->qd_sbd != sdp)
254                         continue;
255                 if (lockref_get_not_dead(&qd->qd_lockref)) {
256                         list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
257                         return qd;
258                 }
259         }
260 
261         return NULL;
262 }
263 
264 
265 static int qd_get(struct gfs2_sbd *sdp, struct kqid qid,
266                   struct gfs2_quota_data **qdp)
267 {
268         struct gfs2_quota_data *qd, *new_qd;
269         unsigned int hash = gfs2_qd_hash(sdp, qid);
270 
271         rcu_read_lock();
272         *qdp = qd = gfs2_qd_search_bucket(hash, sdp, qid);
273         rcu_read_unlock();
274 
275         if (qd)
276                 return 0;
277 
278         new_qd = qd_alloc(hash, sdp, qid);
279         if (!new_qd)
280                 return -ENOMEM;
281 
282         spin_lock(&qd_lock);
283         spin_lock_bucket(hash);
284         *qdp = qd = gfs2_qd_search_bucket(hash, sdp, qid);
285         if (qd == NULL) {
286                 *qdp = new_qd;
287                 list_add(&new_qd->qd_list, &sdp->sd_quota_list);
288                 hlist_bl_add_head_rcu(&new_qd->qd_hlist, &qd_hash_table[hash]);
289                 atomic_inc(&sdp->sd_quota_count);
290         }
291         spin_unlock_bucket(hash);
292         spin_unlock(&qd_lock);
293 
294         if (qd) {
295                 gfs2_glock_put(new_qd->qd_gl);
296                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
297         }
298 
299         return 0;
300 }
301 
302 
303 static void qd_hold(struct gfs2_quota_data *qd)
304 {
305         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
306         gfs2_assert(sdp, !__lockref_is_dead(&qd->qd_lockref));
307         lockref_get(&qd->qd_lockref);
308 }
309 
310 static void qd_put(struct gfs2_quota_data *qd)
311 {
312         if (lockref_put_or_lock(&qd->qd_lockref))
313                 return;
314 
315         qd->qd_lockref.count = 0;
316         list_lru_add(&gfs2_qd_lru, &qd->qd_lru);
317         spin_unlock(&qd->qd_lockref.lock);
318 
319 }
320 
321 static int slot_get(struct gfs2_quota_data *qd)
322 {
323         struct gfs2_sbd *sdp = qd->qd_sbd;
324         unsigned int bit;
325         int error = 0;
326 
327         spin_lock(&sdp->sd_bitmap_lock);
328         if (qd->qd_slot_count != 0)
329                 goto out;
330 
331         error = -ENOSPC;
332         bit = find_first_zero_bit(sdp->sd_quota_bitmap, sdp->sd_quota_slots);
333         if (bit < sdp->sd_quota_slots) {
334                 set_bit(bit, sdp->sd_quota_bitmap);
335                 qd->qd_slot = bit;
336                 error = 0;
337 out:
338                 qd->qd_slot_count++;
339         }
340         spin_unlock(&sdp->sd_bitmap_lock);
341 
342         return error;
343 }
344 
345 static void slot_hold(struct gfs2_quota_data *qd)
346 {
347         struct gfs2_sbd *sdp = qd->qd_sbd;
348 
349         spin_lock(&sdp->sd_bitmap_lock);
350         gfs2_assert(sdp, qd->qd_slot_count);
351         qd->qd_slot_count++;
352         spin_unlock(&sdp->sd_bitmap_lock);
353 }
354 
355 static void slot_put(struct gfs2_quota_data *qd)
356 {
357         struct gfs2_sbd *sdp = qd->qd_sbd;
358 
359         spin_lock(&sdp->sd_bitmap_lock);
360         gfs2_assert(sdp, qd->qd_slot_count);
361         if (!--qd->qd_slot_count) {
362                 BUG_ON(!test_and_clear_bit(qd->qd_slot, sdp->sd_quota_bitmap));
363                 qd->qd_slot = -1;
364         }
365         spin_unlock(&sdp->sd_bitmap_lock);
366 }
367 
368 static int bh_get(struct gfs2_quota_data *qd)
369 {
370         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
371         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
372         unsigned int block, offset;
373         struct buffer_head *bh;
374         int error;
375         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
376 
377         mutex_lock(&sdp->sd_quota_mutex);
378 
379         if (qd->qd_bh_count++) {
380                 mutex_unlock(&sdp->sd_quota_mutex);
381                 return 0;
382         }
383 
384         block = qd->qd_slot / sdp->sd_qc_per_block;
385         offset = qd->qd_slot % sdp->sd_qc_per_block;
386 
387         bh_map.b_size = 1 << ip->i_inode.i_blkbits;
388         error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
389         if (error)
390                 goto fail;
391         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
392         if (error)
393                 goto fail;
394         error = -EIO;
395         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
396                 goto fail_brelse;
397 
398         qd->qd_bh = bh;
399         qd->qd_bh_qc = (struct gfs2_quota_change *)
400                 (bh->b_data + sizeof(struct gfs2_meta_header) +
401                  offset * sizeof(struct gfs2_quota_change));
402 
403         mutex_unlock(&sdp->sd_quota_mutex);
404 
405         return 0;
406 
407 fail_brelse:
408         brelse(bh);
409 fail:
410         qd->qd_bh_count--;
411         mutex_unlock(&sdp->sd_quota_mutex);
412         return error;
413 }
414 
415 static void bh_put(struct gfs2_quota_data *qd)
416 {
417         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
418 
419         mutex_lock(&sdp->sd_quota_mutex);
420         gfs2_assert(sdp, qd->qd_bh_count);
421         if (!--qd->qd_bh_count) {
422                 brelse(qd->qd_bh);
423                 qd->qd_bh = NULL;
424                 qd->qd_bh_qc = NULL;
425         }
426         mutex_unlock(&sdp->sd_quota_mutex);
427 }
428 
429 static int qd_check_sync(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd,
430                          u64 *sync_gen)
431 {
432         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
433             !test_bit(QDF_CHANGE, &qd->qd_flags) ||
434             (sync_gen && (qd->qd_sync_gen >= *sync_gen)))
435                 return 0;
436 
437         if (!lockref_get_not_dead(&qd->qd_lockref))
438                 return 0;
439 
440         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
441         set_bit(QDF_LOCKED, &qd->qd_flags);
442         qd->qd_change_sync = qd->qd_change;
443         slot_hold(qd);
444         return 1;
445 }
446 
447 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
448 {
449         struct gfs2_quota_data *qd = NULL;
450         int error;
451         int found = 0;
452 
453         *qdp = NULL;
454 
455         if (sdp->sd_vfs->s_flags & MS_RDONLY)
456                 return 0;
457 
458         spin_lock(&qd_lock);
459 
460         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
461                 found = qd_check_sync(sdp, qd, &sdp->sd_quota_sync_gen);
462                 if (found)
463                         break;
464         }
465 
466         if (!found)
467                 qd = NULL;
468 
469         spin_unlock(&qd_lock);
470 
471         if (qd) {
472                 gfs2_assert_warn(sdp, qd->qd_change_sync);
473                 error = bh_get(qd);
474                 if (error) {
475                         clear_bit(QDF_LOCKED, &qd->qd_flags);
476                         slot_put(qd);
477                         qd_put(qd);
478                         return error;
479                 }
480         }
481 
482         *qdp = qd;
483 
484         return 0;
485 }
486 
487 static void qd_unlock(struct gfs2_quota_data *qd)
488 {
489         gfs2_assert_warn(qd->qd_gl->gl_name.ln_sbd,
490                          test_bit(QDF_LOCKED, &qd->qd_flags));
491         clear_bit(QDF_LOCKED, &qd->qd_flags);
492         bh_put(qd);
493         slot_put(qd);
494         qd_put(qd);
495 }
496 
497 static int qdsb_get(struct gfs2_sbd *sdp, struct kqid qid,
498                     struct gfs2_quota_data **qdp)
499 {
500         int error;
501 
502         error = qd_get(sdp, qid, qdp);
503         if (error)
504                 return error;
505 
506         error = slot_get(*qdp);
507         if (error)
508                 goto fail;
509 
510         error = bh_get(*qdp);
511         if (error)
512                 goto fail_slot;
513 
514         return 0;
515 
516 fail_slot:
517         slot_put(*qdp);
518 fail:
519         qd_put(*qdp);
520         return error;
521 }
522 
523 static void qdsb_put(struct gfs2_quota_data *qd)
524 {
525         bh_put(qd);
526         slot_put(qd);
527         qd_put(qd);
528 }
529 
530 int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
531 {
532         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
533         struct gfs2_quota_data **qd;
534         int error;
535 
536         if (ip->i_res == NULL) {
537                 error = gfs2_rs_alloc(ip);
538                 if (error)
539                         return error;
540         }
541 
542         qd = ip->i_res->rs_qa_qd;
543 
544         if (gfs2_assert_warn(sdp, !ip->i_res->rs_qa_qd_num) ||
545             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
546                 return -EIO;
547 
548         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
549                 return 0;
550 
551         error = qdsb_get(sdp, make_kqid_uid(ip->i_inode.i_uid), qd);
552         if (error)
553                 goto out;
554         ip->i_res->rs_qa_qd_num++;
555         qd++;
556 
557         error = qdsb_get(sdp, make_kqid_gid(ip->i_inode.i_gid), qd);
558         if (error)
559                 goto out;
560         ip->i_res->rs_qa_qd_num++;
561         qd++;
562 
563         if (!uid_eq(uid, NO_UID_QUOTA_CHANGE) &&
564             !uid_eq(uid, ip->i_inode.i_uid)) {
565                 error = qdsb_get(sdp, make_kqid_uid(uid), qd);
566                 if (error)
567                         goto out;
568                 ip->i_res->rs_qa_qd_num++;
569                 qd++;
570         }
571 
572         if (!gid_eq(gid, NO_GID_QUOTA_CHANGE) &&
573             !gid_eq(gid, ip->i_inode.i_gid)) {
574                 error = qdsb_get(sdp, make_kqid_gid(gid), qd);
575                 if (error)
576                         goto out;
577                 ip->i_res->rs_qa_qd_num++;
578                 qd++;
579         }
580 
581 out:
582         if (error)
583                 gfs2_quota_unhold(ip);
584         return error;
585 }
586 
587 void gfs2_quota_unhold(struct gfs2_inode *ip)
588 {
589         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
590         unsigned int x;
591 
592         if (ip->i_res == NULL)
593                 return;
594         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
595 
596         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
597                 qdsb_put(ip->i_res->rs_qa_qd[x]);
598                 ip->i_res->rs_qa_qd[x] = NULL;
599         }
600         ip->i_res->rs_qa_qd_num = 0;
601 }
602 
603 static int sort_qd(const void *a, const void *b)
604 {
605         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
606         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
607 
608         if (qid_lt(qd_a->qd_id, qd_b->qd_id))
609                 return -1;
610         if (qid_lt(qd_b->qd_id, qd_a->qd_id))
611                 return 1;
612         return 0;
613 }
614 
615 static void do_qc(struct gfs2_quota_data *qd, s64 change)
616 {
617         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
618         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
619         struct gfs2_quota_change *qc = qd->qd_bh_qc;
620         s64 x;
621 
622         mutex_lock(&sdp->sd_quota_mutex);
623         gfs2_trans_add_meta(ip->i_gl, qd->qd_bh);
624 
625         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
626                 qc->qc_change = 0;
627                 qc->qc_flags = 0;
628                 if (qd->qd_id.type == USRQUOTA)
629                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
630                 qc->qc_id = cpu_to_be32(from_kqid(&init_user_ns, qd->qd_id));
631         }
632 
633         x = be64_to_cpu(qc->qc_change) + change;
634         qc->qc_change = cpu_to_be64(x);
635 
636         spin_lock(&qd_lock);
637         qd->qd_change = x;
638         spin_unlock(&qd_lock);
639 
640         if (!x) {
641                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
642                 clear_bit(QDF_CHANGE, &qd->qd_flags);
643                 qc->qc_flags = 0;
644                 qc->qc_id = 0;
645                 slot_put(qd);
646                 qd_put(qd);
647         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
648                 qd_hold(qd);
649                 slot_hold(qd);
650         }
651 
652         if (change < 0) /* Reset quiet flag if we freed some blocks */
653                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
654         mutex_unlock(&sdp->sd_quota_mutex);
655 }
656 
657 static int gfs2_write_buf_to_page(struct gfs2_inode *ip, unsigned long index,
658                                   unsigned off, void *buf, unsigned bytes)
659 {
660         struct inode *inode = &ip->i_inode;
661         struct gfs2_sbd *sdp = GFS2_SB(inode);
662         struct address_space *mapping = inode->i_mapping;
663         struct page *page;
664         struct buffer_head *bh;
665         void *kaddr;
666         u64 blk;
667         unsigned bsize = sdp->sd_sb.sb_bsize, bnum = 0, boff = 0;
668         unsigned to_write = bytes, pg_off = off;
669         int done = 0;
670 
671         blk = index << (PAGE_CACHE_SHIFT - sdp->sd_sb.sb_bsize_shift);
672         boff = off % bsize;
673 
674         page = find_or_create_page(mapping, index, GFP_NOFS);
675         if (!page)
676                 return -ENOMEM;
677         if (!page_has_buffers(page))
678                 create_empty_buffers(page, bsize, 0);
679 
680         bh = page_buffers(page);
681         while (!done) {
682                 /* Find the beginning block within the page */
683                 if (pg_off >= ((bnum * bsize) + bsize)) {
684                         bh = bh->b_this_page;
685                         bnum++;
686                         blk++;
687                         continue;
688                 }
689                 if (!buffer_mapped(bh)) {
690                         gfs2_block_map(inode, blk, bh, 1);
691                         if (!buffer_mapped(bh))
692                                 goto unlock_out;
693                         /* If it's a newly allocated disk block, zero it */
694                         if (buffer_new(bh))
695                                 zero_user(page, bnum * bsize, bh->b_size);
696                 }
697                 if (PageUptodate(page))
698                         set_buffer_uptodate(bh);
699                 if (!buffer_uptodate(bh)) {
700                         ll_rw_block(READ | REQ_META, 1, &bh);
701                         wait_on_buffer(bh);
702                         if (!buffer_uptodate(bh))
703                                 goto unlock_out;
704                 }
705                 gfs2_trans_add_data(ip->i_gl, bh);
706 
707                 /* If we need to write to the next block as well */
708                 if (to_write > (bsize - boff)) {
709                         pg_off += (bsize - boff);
710                         to_write -= (bsize - boff);
711                         boff = pg_off % bsize;
712                         continue;
713                 }
714                 done = 1;
715         }
716 
717         /* Write to the page, now that we have setup the buffer(s) */
718         kaddr = kmap_atomic(page);
719         memcpy(kaddr + off, buf, bytes);
720         flush_dcache_page(page);
721         kunmap_atomic(kaddr);
722         unlock_page(page);
723         page_cache_release(page);
724 
725         return 0;
726 
727 unlock_out:
728         unlock_page(page);
729         page_cache_release(page);
730         return -EIO;
731 }
732 
733 static int gfs2_write_disk_quota(struct gfs2_inode *ip, struct gfs2_quota *qp,
734                                  loff_t loc)
735 {
736         unsigned long pg_beg;
737         unsigned pg_off, nbytes, overflow = 0;
738         int pg_oflow = 0, error;
739         void *ptr;
740 
741         nbytes = sizeof(struct gfs2_quota);
742 
743         pg_beg = loc >> PAGE_CACHE_SHIFT;
744         pg_off = loc % PAGE_CACHE_SIZE;
745 
746         /* If the quota straddles a page boundary, split the write in two */
747         if ((pg_off + nbytes) > PAGE_CACHE_SIZE) {
748                 pg_oflow = 1;
749                 overflow = (pg_off + nbytes) - PAGE_CACHE_SIZE;
750         }
751 
752         ptr = qp;
753         error = gfs2_write_buf_to_page(ip, pg_beg, pg_off, ptr,
754                                        nbytes - overflow);
755         /* If there's an overflow, write the remaining bytes to the next page */
756         if (!error && pg_oflow)
757                 error = gfs2_write_buf_to_page(ip, pg_beg + 1, 0,
758                                                ptr + nbytes - overflow,
759                                                overflow);
760         return error;
761 }
762 
763 /**
764  * gfs2_adjust_quota - adjust record of current block usage
765  * @ip: The quota inode
766  * @loc: Offset of the entry in the quota file
767  * @change: The amount of usage change to record
768  * @qd: The quota data
769  * @fdq: The updated limits to record
770  *
771  * This function was mostly borrowed from gfs2_block_truncate_page which was
772  * in turn mostly borrowed from ext3
773  *
774  * Returns: 0 or -ve on error
775  */
776 
777 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
778                              s64 change, struct gfs2_quota_data *qd,
779                              struct qc_dqblk *fdq)
780 {
781         struct inode *inode = &ip->i_inode;
782         struct gfs2_sbd *sdp = GFS2_SB(inode);
783         struct gfs2_quota q;
784         int err;
785         u64 size;
786 
787         if (gfs2_is_stuffed(ip)) {
788                 err = gfs2_unstuff_dinode(ip, NULL);
789                 if (err)
790                         return err;
791         }
792 
793         memset(&q, 0, sizeof(struct gfs2_quota));
794         err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
795         if (err < 0)
796                 return err;
797 
798         loc -= sizeof(q); /* gfs2_internal_read would've advanced the loc ptr */
799         err = -EIO;
800         be64_add_cpu(&q.qu_value, change);
801         if (((s64)be64_to_cpu(q.qu_value)) < 0)
802                 q.qu_value = 0; /* Never go negative on quota usage */
803         qd->qd_qb.qb_value = q.qu_value;
804         if (fdq) {
805                 if (fdq->d_fieldmask & QC_SPC_SOFT) {
806                         q.qu_warn = cpu_to_be64(fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift);
807                         qd->qd_qb.qb_warn = q.qu_warn;
808                 }
809                 if (fdq->d_fieldmask & QC_SPC_HARD) {
810                         q.qu_limit = cpu_to_be64(fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift);
811                         qd->qd_qb.qb_limit = q.qu_limit;
812                 }
813                 if (fdq->d_fieldmask & QC_SPACE) {
814                         q.qu_value = cpu_to_be64(fdq->d_space >> sdp->sd_sb.sb_bsize_shift);
815                         qd->qd_qb.qb_value = q.qu_value;
816                 }
817         }
818 
819         err = gfs2_write_disk_quota(ip, &q, loc);
820         if (!err) {
821                 size = loc + sizeof(struct gfs2_quota);
822                 if (size > inode->i_size)
823                         i_size_write(inode, size);
824                 inode->i_mtime = inode->i_atime = CURRENT_TIME;
825                 mark_inode_dirty(inode);
826                 set_bit(QDF_REFRESH, &qd->qd_flags);
827         }
828 
829         return err;
830 }
831 
832 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
833 {
834         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_name.ln_sbd;
835         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
836         struct gfs2_alloc_parms ap = { .aflags = 0, };
837         unsigned int data_blocks, ind_blocks;
838         struct gfs2_holder *ghs, i_gh;
839         unsigned int qx, x;
840         struct gfs2_quota_data *qd;
841         unsigned reserved;
842         loff_t offset;
843         unsigned int nalloc = 0, blocks;
844         int error;
845 
846         error = gfs2_rs_alloc(ip);
847         if (error)
848                 return error;
849 
850         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
851                               &data_blocks, &ind_blocks);
852 
853         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
854         if (!ghs)
855                 return -ENOMEM;
856 
857         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
858         mutex_lock(&ip->i_inode.i_mutex);
859         for (qx = 0; qx < num_qd; qx++) {
860                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
861                                            GL_NOCACHE, &ghs[qx]);
862                 if (error)
863                         goto out;
864         }
865 
866         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
867         if (error)
868                 goto out;
869 
870         for (x = 0; x < num_qd; x++) {
871                 offset = qd2offset(qda[x]);
872                 if (gfs2_write_alloc_required(ip, offset,
873                                               sizeof(struct gfs2_quota)))
874                         nalloc++;
875         }
876 
877         /* 
878          * 1 blk for unstuffing inode if stuffed. We add this extra
879          * block to the reservation unconditionally. If the inode
880          * doesn't need unstuffing, the block will be released to the 
881          * rgrp since it won't be allocated during the transaction
882          */
883         /* +3 in the end for unstuffing block, inode size update block
884          * and another block in case quota straddles page boundary and 
885          * two blocks need to be updated instead of 1 */
886         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
887 
888         reserved = 1 + (nalloc * (data_blocks + ind_blocks));
889         ap.target = reserved;
890         error = gfs2_inplace_reserve(ip, &ap);
891         if (error)
892                 goto out_alloc;
893 
894         if (nalloc)
895                 blocks += gfs2_rg_blocks(ip, reserved) + nalloc * ind_blocks + RES_STATFS;
896 
897         error = gfs2_trans_begin(sdp, blocks, 0);
898         if (error)
899                 goto out_ipres;
900 
901         for (x = 0; x < num_qd; x++) {
902                 qd = qda[x];
903                 offset = qd2offset(qd);
904                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
905                 if (error)
906                         goto out_end_trans;
907 
908                 do_qc(qd, -qd->qd_change_sync);
909                 set_bit(QDF_REFRESH, &qd->qd_flags);
910         }
911 
912         error = 0;
913 
914 out_end_trans:
915         gfs2_trans_end(sdp);
916 out_ipres:
917         gfs2_inplace_release(ip);
918 out_alloc:
919         gfs2_glock_dq_uninit(&i_gh);
920 out:
921         while (qx--)
922                 gfs2_glock_dq_uninit(&ghs[qx]);
923         mutex_unlock(&ip->i_inode.i_mutex);
924         kfree(ghs);
925         gfs2_log_flush(ip->i_gl->gl_name.ln_sbd, ip->i_gl, NORMAL_FLUSH);
926         return error;
927 }
928 
929 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
930 {
931         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
932         struct gfs2_quota q;
933         struct gfs2_quota_lvb *qlvb;
934         loff_t pos;
935         int error;
936 
937         memset(&q, 0, sizeof(struct gfs2_quota));
938         pos = qd2offset(qd);
939         error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
940         if (error < 0)
941                 return error;
942 
943         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
944         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
945         qlvb->__pad = 0;
946         qlvb->qb_limit = q.qu_limit;
947         qlvb->qb_warn = q.qu_warn;
948         qlvb->qb_value = q.qu_value;
949         qd->qd_qb = *qlvb;
950 
951         return 0;
952 }
953 
954 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
955                     struct gfs2_holder *q_gh)
956 {
957         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
958         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
959         struct gfs2_holder i_gh;
960         int error;
961 
962 restart:
963         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
964         if (error)
965                 return error;
966 
967         if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
968                 force_refresh = FORCE;
969 
970         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
971 
972         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
973                 gfs2_glock_dq_uninit(q_gh);
974                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
975                                            GL_NOCACHE, q_gh);
976                 if (error)
977                         return error;
978 
979                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
980                 if (error)
981                         goto fail;
982 
983                 error = update_qd(sdp, qd);
984                 if (error)
985                         goto fail_gunlock;
986 
987                 gfs2_glock_dq_uninit(&i_gh);
988                 gfs2_glock_dq_uninit(q_gh);
989                 force_refresh = 0;
990                 goto restart;
991         }
992 
993         return 0;
994 
995 fail_gunlock:
996         gfs2_glock_dq_uninit(&i_gh);
997 fail:
998         gfs2_glock_dq_uninit(q_gh);
999         return error;
1000 }
1001 
1002 int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
1003 {
1004         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1005         struct gfs2_quota_data *qd;
1006         unsigned int x;
1007         int error = 0;
1008 
1009         error = gfs2_quota_hold(ip, uid, gid);
1010         if (error)
1011                 return error;
1012 
1013         if (capable(CAP_SYS_RESOURCE) ||
1014             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1015                 return 0;
1016 
1017         sort(ip->i_res->rs_qa_qd, ip->i_res->rs_qa_qd_num,
1018              sizeof(struct gfs2_quota_data *), sort_qd, NULL);
1019 
1020         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1021                 qd = ip->i_res->rs_qa_qd[x];
1022                 error = do_glock(qd, NO_FORCE, &ip->i_res->rs_qa_qd_ghs[x]);
1023                 if (error)
1024                         break;
1025         }
1026 
1027         if (!error)
1028                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
1029         else {
1030                 while (x--)
1031                         gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
1032                 gfs2_quota_unhold(ip);
1033         }
1034 
1035         return error;
1036 }
1037 
1038 static int need_sync(struct gfs2_quota_data *qd)
1039 {
1040         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1041         struct gfs2_tune *gt = &sdp->sd_tune;
1042         s64 value;
1043         unsigned int num, den;
1044         int do_sync = 1;
1045 
1046         if (!qd->qd_qb.qb_limit)
1047                 return 0;
1048 
1049         spin_lock(&qd_lock);
1050         value = qd->qd_change;
1051         spin_unlock(&qd_lock);
1052 
1053         spin_lock(&gt->gt_spin);
1054         num = gt->gt_quota_scale_num;
1055         den = gt->gt_quota_scale_den;
1056         spin_unlock(&gt->gt_spin);
1057 
1058         if (value < 0)
1059                 do_sync = 0;
1060         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
1061                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1062                 do_sync = 0;
1063         else {
1064                 value *= gfs2_jindex_size(sdp) * num;
1065                 value = div_s64(value, den);
1066                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
1067                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1068                         do_sync = 0;
1069         }
1070 
1071         return do_sync;
1072 }
1073 
1074 void gfs2_quota_unlock(struct gfs2_inode *ip)
1075 {
1076         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1077         struct gfs2_quota_data *qda[4];
1078         unsigned int count = 0;
1079         unsigned int x;
1080         int found;
1081 
1082         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1083                 goto out;
1084 
1085         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1086                 struct gfs2_quota_data *qd;
1087                 int sync;
1088 
1089                 qd = ip->i_res->rs_qa_qd[x];
1090                 sync = need_sync(qd);
1091 
1092                 gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
1093                 if (!sync)
1094                         continue;
1095 
1096                 spin_lock(&qd_lock);
1097                 found = qd_check_sync(sdp, qd, NULL);
1098                 spin_unlock(&qd_lock);
1099 
1100                 if (!found)
1101                         continue;
1102 
1103                 gfs2_assert_warn(sdp, qd->qd_change_sync);
1104                 if (bh_get(qd)) {
1105                         clear_bit(QDF_LOCKED, &qd->qd_flags);
1106                         slot_put(qd);
1107                         qd_put(qd);
1108                         continue;
1109                 }
1110 
1111                 qda[count++] = qd;
1112         }
1113 
1114         if (count) {
1115                 do_sync(count, qda);
1116                 for (x = 0; x < count; x++)
1117                         qd_unlock(qda[x]);
1118         }
1119 
1120 out:
1121         gfs2_quota_unhold(ip);
1122 }
1123 
1124 #define MAX_LINE 256
1125 
1126 static int print_message(struct gfs2_quota_data *qd, char *type)
1127 {
1128         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1129 
1130         fs_info(sdp, "quota %s for %s %u\n",
1131                 type,
1132                 (qd->qd_id.type == USRQUOTA) ? "user" : "group",
1133                 from_kqid(&init_user_ns, qd->qd_id));
1134 
1135         return 0;
1136 }
1137 
1138 /**
1139  * gfs2_quota_check - check if allocating new blocks will exceed quota
1140  * @ip:  The inode for which this check is being performed
1141  * @uid: The uid to check against
1142  * @gid: The gid to check against
1143  * @ap:  The allocation parameters. ap->target contains the requested
1144  *       blocks. ap->min_target, if set, contains the minimum blks
1145  *       requested.
1146  *
1147  * Returns: 0 on success.
1148  *                  min_req = ap->min_target ? ap->min_target : ap->target;
1149  *                  quota must allow atleast min_req blks for success and
1150  *                  ap->allowed is set to the number of blocks allowed
1151  *
1152  *          -EDQUOT otherwise, quota violation. ap->allowed is set to number
1153  *                  of blocks available.
1154  */
1155 int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid,
1156                      struct gfs2_alloc_parms *ap)
1157 {
1158         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1159         struct gfs2_quota_data *qd;
1160         s64 value, warn, limit;
1161         unsigned int x;
1162         int error = 0;
1163 
1164         ap->allowed = UINT_MAX; /* Assume we are permitted a whole lot */
1165         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1166                 return 0;
1167 
1168         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1169                 return 0;
1170 
1171         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1172                 qd = ip->i_res->rs_qa_qd[x];
1173 
1174                 if (!(qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1175                       qid_eq(qd->qd_id, make_kqid_gid(gid))))
1176                         continue;
1177 
1178                 warn = (s64)be64_to_cpu(qd->qd_qb.qb_warn);
1179                 limit = (s64)be64_to_cpu(qd->qd_qb.qb_limit);
1180                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1181                 spin_lock(&qd_lock);
1182                 value += qd->qd_change;
1183                 spin_unlock(&qd_lock);
1184 
1185                 if (limit > 0 && (limit - value) < ap->allowed)
1186                         ap->allowed = limit - value;
1187                 /* If we can't meet the target */
1188                 if (limit && limit < (value + (s64)ap->target)) {
1189                         /* If no min_target specified or we don't meet
1190                          * min_target, return -EDQUOT */
1191                         if (!ap->min_target || ap->min_target > ap->allowed) {
1192                                 if (!test_and_set_bit(QDF_QMSG_QUIET,
1193                                                       &qd->qd_flags)) {
1194                                         print_message(qd, "exceeded");
1195                                         quota_send_warning(qd->qd_id,
1196                                                            sdp->sd_vfs->s_dev,
1197                                                            QUOTA_NL_BHARDWARN);
1198                                 }
1199                                 error = -EDQUOT;
1200                                 break;
1201                         }
1202                 } else if (warn && warn < value &&
1203                            time_after_eq(jiffies, qd->qd_last_warn +
1204                                          gfs2_tune_get(sdp, gt_quota_warn_period)
1205                                          * HZ)) {
1206                         quota_send_warning(qd->qd_id,
1207                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1208                         error = print_message(qd, "warning");
1209                         qd->qd_last_warn = jiffies;
1210                 }
1211         }
1212         return error;
1213 }
1214 
1215 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1216                        kuid_t uid, kgid_t gid)
1217 {
1218         struct gfs2_quota_data *qd;
1219         unsigned int x;
1220 
1221         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1222                 return;
1223         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1224                 return;
1225 
1226         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1227                 qd = ip->i_res->rs_qa_qd[x];
1228 
1229                 if (qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1230                     qid_eq(qd->qd_id, make_kqid_gid(gid))) {
1231                         do_qc(qd, change);
1232                 }
1233         }
1234 }
1235 
1236 int gfs2_quota_sync(struct super_block *sb, int type)
1237 {
1238         struct gfs2_sbd *sdp = sb->s_fs_info;
1239         struct gfs2_quota_data **qda;
1240         unsigned int max_qd = PAGE_SIZE/sizeof(struct gfs2_holder);
1241         unsigned int num_qd;
1242         unsigned int x;
1243         int error = 0;
1244 
1245         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1246         if (!qda)
1247                 return -ENOMEM;
1248 
1249         mutex_lock(&sdp->sd_quota_sync_mutex);
1250         sdp->sd_quota_sync_gen++;
1251 
1252         do {
1253                 num_qd = 0;
1254 
1255                 for (;;) {
1256                         error = qd_fish(sdp, qda + num_qd);
1257                         if (error || !qda[num_qd])
1258                                 break;
1259                         if (++num_qd == max_qd)
1260                                 break;
1261                 }
1262 
1263                 if (num_qd) {
1264                         if (!error)
1265                                 error = do_sync(num_qd, qda);
1266                         if (!error)
1267                                 for (x = 0; x < num_qd; x++)
1268                                         qda[x]->qd_sync_gen =
1269                                                 sdp->sd_quota_sync_gen;
1270 
1271                         for (x = 0; x < num_qd; x++)
1272                                 qd_unlock(qda[x]);
1273                 }
1274         } while (!error && num_qd == max_qd);
1275 
1276         mutex_unlock(&sdp->sd_quota_sync_mutex);
1277         kfree(qda);
1278 
1279         return error;
1280 }
1281 
1282 int gfs2_quota_refresh(struct gfs2_sbd *sdp, struct kqid qid)
1283 {
1284         struct gfs2_quota_data *qd;
1285         struct gfs2_holder q_gh;
1286         int error;
1287 
1288         error = qd_get(sdp, qid, &qd);
1289         if (error)
1290                 return error;
1291 
1292         error = do_glock(qd, FORCE, &q_gh);
1293         if (!error)
1294                 gfs2_glock_dq_uninit(&q_gh);
1295 
1296         qd_put(qd);
1297         return error;
1298 }
1299 
1300 int gfs2_quota_init(struct gfs2_sbd *sdp)
1301 {
1302         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1303         u64 size = i_size_read(sdp->sd_qc_inode);
1304         unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1305         unsigned int x, slot = 0;
1306         unsigned int found = 0;
1307         unsigned int hash;
1308         unsigned int bm_size;
1309         u64 dblock;
1310         u32 extlen = 0;
1311         int error;
1312 
1313         if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1314                 return -EIO;
1315 
1316         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1317         bm_size = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * sizeof(unsigned long));
1318         bm_size *= sizeof(unsigned long);
1319         error = -ENOMEM;
1320         sdp->sd_quota_bitmap = kzalloc(bm_size, GFP_NOFS | __GFP_NOWARN);
1321         if (sdp->sd_quota_bitmap == NULL)
1322                 sdp->sd_quota_bitmap = __vmalloc(bm_size, GFP_NOFS |
1323                                                  __GFP_ZERO, PAGE_KERNEL);
1324         if (!sdp->sd_quota_bitmap)
1325                 return error;
1326 
1327         for (x = 0; x < blocks; x++) {
1328                 struct buffer_head *bh;
1329                 const struct gfs2_quota_change *qc;
1330                 unsigned int y;
1331 
1332                 if (!extlen) {
1333                         int new = 0;
1334                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1335                         if (error)
1336                                 goto fail;
1337                 }
1338                 error = -EIO;
1339                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1340                 if (!bh)
1341                         goto fail;
1342                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1343                         brelse(bh);
1344                         goto fail;
1345                 }
1346 
1347                 qc = (const struct gfs2_quota_change *)(bh->b_data + sizeof(struct gfs2_meta_header));
1348                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1349                      y++, slot++) {
1350                         struct gfs2_quota_data *qd;
1351                         s64 qc_change = be64_to_cpu(qc->qc_change);
1352                         u32 qc_flags = be32_to_cpu(qc->qc_flags);
1353                         enum quota_type qtype = (qc_flags & GFS2_QCF_USER) ?
1354                                                 USRQUOTA : GRPQUOTA;
1355                         struct kqid qc_id = make_kqid(&init_user_ns, qtype,
1356                                                       be32_to_cpu(qc->qc_id));
1357                         qc++;
1358                         if (!qc_change)
1359                                 continue;
1360 
1361                         hash = gfs2_qd_hash(sdp, qc_id);
1362                         qd = qd_alloc(hash, sdp, qc_id);
1363                         if (qd == NULL) {
1364                                 brelse(bh);
1365                                 goto fail;
1366                         }
1367 
1368                         set_bit(QDF_CHANGE, &qd->qd_flags);
1369                         qd->qd_change = qc_change;
1370                         qd->qd_slot = slot;
1371                         qd->qd_slot_count = 1;
1372 
1373                         spin_lock(&qd_lock);
1374                         BUG_ON(test_and_set_bit(slot, sdp->sd_quota_bitmap));
1375                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1376                         atomic_inc(&sdp->sd_quota_count);
1377                         spin_unlock(&qd_lock);
1378 
1379                         spin_lock_bucket(hash);
1380                         hlist_bl_add_head_rcu(&qd->qd_hlist, &qd_hash_table[hash]);
1381                         spin_unlock_bucket(hash);
1382 
1383                         found++;
1384                 }
1385 
1386                 brelse(bh);
1387                 dblock++;
1388                 extlen--;
1389         }
1390 
1391         if (found)
1392                 fs_info(sdp, "found %u quota changes\n", found);
1393 
1394         return 0;
1395 
1396 fail:
1397         gfs2_quota_cleanup(sdp);
1398         return error;
1399 }
1400 
1401 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1402 {
1403         struct list_head *head = &sdp->sd_quota_list;
1404         struct gfs2_quota_data *qd;
1405 
1406         spin_lock(&qd_lock);
1407         while (!list_empty(head)) {
1408                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1409 
1410                 list_del(&qd->qd_list);
1411 
1412                 /* Also remove if this qd exists in the reclaim list */
1413                 list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
1414                 atomic_dec(&sdp->sd_quota_count);
1415                 spin_unlock(&qd_lock);
1416 
1417                 spin_lock_bucket(qd->qd_hash);
1418                 hlist_bl_del_rcu(&qd->qd_hlist);
1419                 spin_unlock_bucket(qd->qd_hash);
1420 
1421                 gfs2_assert_warn(sdp, !qd->qd_change);
1422                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1423                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1424 
1425                 gfs2_glock_put(qd->qd_gl);
1426                 call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
1427 
1428                 spin_lock(&qd_lock);
1429         }
1430         spin_unlock(&qd_lock);
1431 
1432         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1433 
1434         kvfree(sdp->sd_quota_bitmap);
1435         sdp->sd_quota_bitmap = NULL;
1436 }
1437 
1438 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1439 {
1440         if (error == 0 || error == -EROFS)
1441                 return;
1442         if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1443                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1444 }
1445 
1446 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1447                                int (*fxn)(struct super_block *sb, int type),
1448                                unsigned long t, unsigned long *timeo,
1449                                unsigned int *new_timeo)
1450 {
1451         if (t >= *timeo) {
1452                 int error = fxn(sdp->sd_vfs, 0);
1453                 quotad_error(sdp, msg, error);
1454                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1455         } else {
1456                 *timeo -= t;
1457         }
1458 }
1459 
1460 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1461 {
1462         struct gfs2_inode *ip;
1463 
1464         while(1) {
1465                 ip = NULL;
1466                 spin_lock(&sdp->sd_trunc_lock);
1467                 if (!list_empty(&sdp->sd_trunc_list)) {
1468                         ip = list_entry(sdp->sd_trunc_list.next,
1469                                         struct gfs2_inode, i_trunc_list);
1470                         list_del_init(&ip->i_trunc_list);
1471                 }
1472                 spin_unlock(&sdp->sd_trunc_lock);
1473                 if (ip == NULL)
1474                         return;
1475                 gfs2_glock_finish_truncate(ip);
1476         }
1477 }
1478 
1479 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1480         if (!sdp->sd_statfs_force_sync) {
1481                 sdp->sd_statfs_force_sync = 1;
1482                 wake_up(&sdp->sd_quota_wait);
1483         }
1484 }
1485 
1486 
1487 /**
1488  * gfs2_quotad - Write cached quota changes into the quota file
1489  * @sdp: Pointer to GFS2 superblock
1490  *
1491  */
1492 
1493 int gfs2_quotad(void *data)
1494 {
1495         struct gfs2_sbd *sdp = data;
1496         struct gfs2_tune *tune = &sdp->sd_tune;
1497         unsigned long statfs_timeo = 0;
1498         unsigned long quotad_timeo = 0;
1499         unsigned long t = 0;
1500         DEFINE_WAIT(wait);
1501         int empty;
1502 
1503         while (!kthread_should_stop()) {
1504 
1505                 /* Update the master statfs file */
1506                 if (sdp->sd_statfs_force_sync) {
1507                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1508                         quotad_error(sdp, "statfs", error);
1509                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1510                 }
1511                 else
1512                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1513                                            &statfs_timeo,
1514                                            &tune->gt_statfs_quantum);
1515 
1516                 /* Update quota file */
1517                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1518                                    &quotad_timeo, &tune->gt_quota_quantum);
1519 
1520                 /* Check for & recover partially truncated inodes */
1521                 quotad_check_trunc_list(sdp);
1522 
1523                 try_to_freeze();
1524 
1525                 t = min(quotad_timeo, statfs_timeo);
1526 
1527                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1528                 spin_lock(&sdp->sd_trunc_lock);
1529                 empty = list_empty(&sdp->sd_trunc_list);
1530                 spin_unlock(&sdp->sd_trunc_lock);
1531                 if (empty && !sdp->sd_statfs_force_sync)
1532                         t -= schedule_timeout(t);
1533                 else
1534                         t = 0;
1535                 finish_wait(&sdp->sd_quota_wait, &wait);
1536         }
1537 
1538         return 0;
1539 }
1540 
1541 static int gfs2_quota_get_state(struct super_block *sb, struct qc_state *state)
1542 {
1543         struct gfs2_sbd *sdp = sb->s_fs_info;
1544 
1545         memset(state, 0, sizeof(*state));
1546 
1547         switch (sdp->sd_args.ar_quota) {
1548         case GFS2_QUOTA_ON:
1549                 state->s_state[USRQUOTA].flags |= QCI_LIMITS_ENFORCED;
1550                 state->s_state[GRPQUOTA].flags |= QCI_LIMITS_ENFORCED;
1551                 /*FALLTHRU*/
1552         case GFS2_QUOTA_ACCOUNT:
1553                 state->s_state[USRQUOTA].flags |= QCI_ACCT_ENABLED |
1554                                                   QCI_SYSFILE;
1555                 state->s_state[GRPQUOTA].flags |= QCI_ACCT_ENABLED |
1556                                                   QCI_SYSFILE;
1557                 break;
1558         case GFS2_QUOTA_OFF:
1559                 break;
1560         }
1561         if (sdp->sd_quota_inode) {
1562                 state->s_state[USRQUOTA].ino =
1563                                         GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1564                 state->s_state[USRQUOTA].blocks = sdp->sd_quota_inode->i_blocks;
1565         }
1566         state->s_state[USRQUOTA].nextents = 1;  /* unsupported */
1567         state->s_state[GRPQUOTA] = state->s_state[USRQUOTA];
1568         state->s_incoredqs = list_lru_count(&gfs2_qd_lru);
1569         return 0;
1570 }
1571 
1572 static int gfs2_get_dqblk(struct super_block *sb, struct kqid qid,
1573                           struct qc_dqblk *fdq)
1574 {
1575         struct gfs2_sbd *sdp = sb->s_fs_info;
1576         struct gfs2_quota_lvb *qlvb;
1577         struct gfs2_quota_data *qd;
1578         struct gfs2_holder q_gh;
1579         int error;
1580 
1581         memset(fdq, 0, sizeof(*fdq));
1582 
1583         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1584                 return -ESRCH; /* Crazy XFS error code */
1585 
1586         if ((qid.type != USRQUOTA) &&
1587             (qid.type != GRPQUOTA))
1588                 return -EINVAL;
1589 
1590         error = qd_get(sdp, qid, &qd);
1591         if (error)
1592                 return error;
1593         error = do_glock(qd, FORCE, &q_gh);
1594         if (error)
1595                 goto out;
1596 
1597         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1598         fdq->d_spc_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_sb.sb_bsize_shift;
1599         fdq->d_spc_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_sb.sb_bsize_shift;
1600         fdq->d_space = be64_to_cpu(qlvb->qb_value) << sdp->sd_sb.sb_bsize_shift;
1601 
1602         gfs2_glock_dq_uninit(&q_gh);
1603 out:
1604         qd_put(qd);
1605         return error;
1606 }
1607 
1608 /* GFS2 only supports a subset of the XFS fields */
1609 #define GFS2_FIELDMASK (QC_SPC_SOFT|QC_SPC_HARD|QC_SPACE)
1610 
1611 static int gfs2_set_dqblk(struct super_block *sb, struct kqid qid,
1612                           struct qc_dqblk *fdq)
1613 {
1614         struct gfs2_sbd *sdp = sb->s_fs_info;
1615         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1616         struct gfs2_quota_data *qd;
1617         struct gfs2_holder q_gh, i_gh;
1618         unsigned int data_blocks, ind_blocks;
1619         unsigned int blocks = 0;
1620         int alloc_required;
1621         loff_t offset;
1622         int error;
1623 
1624         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1625                 return -ESRCH; /* Crazy XFS error code */
1626 
1627         if ((qid.type != USRQUOTA) &&
1628             (qid.type != GRPQUOTA))
1629                 return -EINVAL;
1630 
1631         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1632                 return -EINVAL;
1633 
1634         error = qd_get(sdp, qid, &qd);
1635         if (error)
1636                 return error;
1637 
1638         error = gfs2_rs_alloc(ip);
1639         if (error)
1640                 goto out_put;
1641 
1642         mutex_lock(&ip->i_inode.i_mutex);
1643         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1644         if (error)
1645                 goto out_unlockput;
1646         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1647         if (error)
1648                 goto out_q;
1649 
1650         /* Check for existing entry, if none then alloc new blocks */
1651         error = update_qd(sdp, qd);
1652         if (error)
1653                 goto out_i;
1654 
1655         /* If nothing has changed, this is a no-op */
1656         if ((fdq->d_fieldmask & QC_SPC_SOFT) &&
1657             ((fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1658                 fdq->d_fieldmask ^= QC_SPC_SOFT;
1659 
1660         if ((fdq->d_fieldmask & QC_SPC_HARD) &&
1661             ((fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1662                 fdq->d_fieldmask ^= QC_SPC_HARD;
1663 
1664         if ((fdq->d_fieldmask & QC_SPACE) &&
1665             ((fdq->d_space >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1666                 fdq->d_fieldmask ^= QC_SPACE;
1667 
1668         if (fdq->d_fieldmask == 0)
1669                 goto out_i;
1670 
1671         offset = qd2offset(qd);
1672         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1673         if (gfs2_is_stuffed(ip))
1674                 alloc_required = 1;
1675         if (alloc_required) {
1676                 struct gfs2_alloc_parms ap = { .aflags = 0, };
1677                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1678                                        &data_blocks, &ind_blocks);
1679                 blocks = 1 + data_blocks + ind_blocks;
1680                 ap.target = blocks;
1681                 error = gfs2_inplace_reserve(ip, &ap);
1682                 if (error)
1683                         goto out_i;
1684                 blocks += gfs2_rg_blocks(ip, blocks);
1685         }
1686 
1687         /* Some quotas span block boundaries and can update two blocks,
1688            adding an extra block to the transaction to handle such quotas */
1689         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1690         if (error)
1691                 goto out_release;
1692 
1693         /* Apply changes */
1694         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1695         if (!error)
1696                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
1697 
1698         gfs2_trans_end(sdp);
1699 out_release:
1700         if (alloc_required)
1701                 gfs2_inplace_release(ip);
1702 out_i:
1703         gfs2_glock_dq_uninit(&i_gh);
1704 out_q:
1705         gfs2_glock_dq_uninit(&q_gh);
1706 out_unlockput:
1707         mutex_unlock(&ip->i_inode.i_mutex);
1708 out_put:
1709         qd_put(qd);
1710         return error;
1711 }
1712 
1713 const struct quotactl_ops gfs2_quotactl_ops = {
1714         .quota_sync     = gfs2_quota_sync,
1715         .get_state      = gfs2_quota_get_state,
1716         .get_dqblk      = gfs2_get_dqblk,
1717         .set_dqblk      = gfs2_set_dqblk,
1718 };
1719 
1720 void __init gfs2_quota_hash_init(void)
1721 {
1722         unsigned i;
1723 
1724         for(i = 0; i < GFS2_QD_HASH_SIZE; i++)
1725                 INIT_HLIST_BL_HEAD(&qd_hash_table[i]);
1726 }
1727 

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