kernel/fs/gfs2/quota.c

   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_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_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_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_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_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_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         mutex_unlock(&sdp->sd_quota_mutex);
 653 }
 654
 655 /**
 656  * gfs2_adjust_quota - adjust record of current block usage
 657  * @ip: The quota inode
 658  * @loc: Offset of the entry in the quota file
 659  * @change: The amount of usage change to record
 660  * @qd: The quota data
 661  * @fdq: The updated limits to record
 662  *
 663  * This function was mostly borrowed from gfs2_block_truncate_page which was
 664  * in turn mostly borrowed from ext3
 665  *
 666  * Returns: 0 or -ve on error
 667  */
 668
 669 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 670                              s64 change, struct gfs2_quota_data *qd,
 671                              struct qc_dqblk *fdq)
 672 {
 673         struct inode *inode = &ip->i_inode;
 674         struct gfs2_sbd *sdp = GFS2_SB(inode);
 675         struct address_space *mapping = inode->i_mapping;
 676         unsigned long index = loc >> PAGE_CACHE_SHIFT;
 677         unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
 678         unsigned blocksize, iblock, pos;
 679         struct buffer_head *bh;
 680         struct page *page;
 681         void *kaddr, *ptr;
 682         struct gfs2_quota q;
 683         int err, nbytes;
 684         u64 size;
 685
 686         if (gfs2_is_stuffed(ip)) {
 687                 err = gfs2_unstuff_dinode(ip, NULL);
 688                 if (err)
 689                         return err;
 690         }
 691
 692         memset(&q, 0, sizeof(struct gfs2_quota));
 693         err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
 694         if (err < 0)
 695                 return err;
 696
 697         err = -EIO;
 698         be64_add_cpu(&q.qu_value, change);
 699         qd->qd_qb.qb_value = q.qu_value;
 700         if (fdq) {
 701                 if (fdq->d_fieldmask & QC_SPC_SOFT) {
 702                         q.qu_warn = cpu_to_be64(fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift);
 703                         qd->qd_qb.qb_warn = q.qu_warn;
 704                 }
 705                 if (fdq->d_fieldmask & QC_SPC_HARD) {
 706                         q.qu_limit = cpu_to_be64(fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift);
 707                         qd->qd_qb.qb_limit = q.qu_limit;
 708                 }
 709                 if (fdq->d_fieldmask & QC_SPACE) {
 710                         q.qu_value = cpu_to_be64(fdq->d_space >> sdp->sd_sb.sb_bsize_shift);
 711                         qd->qd_qb.qb_value = q.qu_value;
 712                 }
 713         }
 714
 715         /* Write the quota into the quota file on disk */
 716         ptr = &q;
 717         nbytes = sizeof(struct gfs2_quota);
 718 get_a_page:
 719         page = find_or_create_page(mapping, index, GFP_NOFS);
 720         if (!page)
 721                 return -ENOMEM;
 722
 723         blocksize = inode->i_sb->s_blocksize;
 724         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
 725
 726         if (!page_has_buffers(page))
 727                 create_empty_buffers(page, blocksize, 0);
 728
 729         bh = page_buffers(page);
 730         pos = blocksize;
 731         while (offset >= pos) {
 732                 bh = bh->b_this_page;
 733                 iblock++;
 734                 pos += blocksize;
 735         }
 736
 737         if (!buffer_mapped(bh)) {
 738                 gfs2_block_map(inode, iblock, bh, 1);
 739                 if (!buffer_mapped(bh))
 740                         goto unlock_out;
 741                 /* If it's a newly allocated disk block for quota, zero it */
 742                 if (buffer_new(bh))
 743                         zero_user(page, pos - blocksize, bh->b_size);
 744         }
 745
 746         if (PageUptodate(page))
 747                 set_buffer_uptodate(bh);
 748
 749         if (!buffer_uptodate(bh)) {
 750                 ll_rw_block(READ | REQ_META, 1, &bh);
 751                 wait_on_buffer(bh);
 752                 if (!buffer_uptodate(bh))
 753                         goto unlock_out;
 754         }
 755
 756         gfs2_trans_add_data(ip->i_gl, bh);
 757
 758         kaddr = kmap_atomic(page);
 759         if (offset + sizeof(struct gfs2_quota) > PAGE_CACHE_SIZE)
 760                 nbytes = PAGE_CACHE_SIZE - offset;
 761         memcpy(kaddr + offset, ptr, nbytes);
 762         flush_dcache_page(page);
 763         kunmap_atomic(kaddr);
 764         unlock_page(page);
 765         page_cache_release(page);
 766
 767         /* If quota straddles page boundary, we need to update the rest of the
 768          * quota at the beginning of the next page */
 769         if ((offset + sizeof(struct gfs2_quota)) > PAGE_CACHE_SIZE) {
 770                 ptr = ptr + nbytes;
 771                 nbytes = sizeof(struct gfs2_quota) - nbytes;
 772                 offset = 0;
 773                 index++;
 774                 goto get_a_page;
 775         }
 776
 777         size = loc + sizeof(struct gfs2_quota);
 778         if (size > inode->i_size)
 779                 i_size_write(inode, size);
 780         inode->i_mtime = inode->i_atime = CURRENT_TIME;
 781         mark_inode_dirty(inode);
 782         set_bit(QDF_REFRESH, &qd->qd_flags);
 783         return 0;
 784
 785 unlock_out:
 786         unlock_page(page);
 787         page_cache_release(page);
 788         return err;
 789 }
 790
 791 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 792 {
 793         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
 794         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 795         struct gfs2_alloc_parms ap = { .aflags = 0, };
 796         unsigned int data_blocks, ind_blocks;
 797         struct gfs2_holder *ghs, i_gh;
 798         unsigned int qx, x;
 799         struct gfs2_quota_data *qd;
 800         unsigned reserved;
 801         loff_t offset;
 802         unsigned int nalloc = 0, blocks;
 803         int error;
 804
 805         error = gfs2_rs_alloc(ip);
 806         if (error)
 807                 return error;
 808
 809         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 810                               &data_blocks, &ind_blocks);
 811
 812         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
 813         if (!ghs)
 814                 return -ENOMEM;
 815
 816         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 817         mutex_lock(&ip->i_inode.i_mutex);
 818         for (qx = 0; qx < num_qd; qx++) {
 819                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
 820                                            GL_NOCACHE, &ghs[qx]);
 821                 if (error)
 822                         goto out;
 823         }
 824
 825         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 826         if (error)
 827                 goto out;
 828
 829         for (x = 0; x < num_qd; x++) {
 830                 offset = qd2offset(qda[x]);
 831                 if (gfs2_write_alloc_required(ip, offset,
 832                                               sizeof(struct gfs2_quota)))
 833                         nalloc++;
 834         }
 835
 836         /*
 837          * 1 blk for unstuffing inode if stuffed. We add this extra
 838          * block to the reservation unconditionally. If the inode
 839          * doesn't need unstuffing, the block will be released to the
 840          * rgrp since it won't be allocated during the transaction
 841          */
 842         /* +3 in the end for unstuffing block, inode size update block
 843          * and another block in case quota straddles page boundary and
 844          * two blocks need to be updated instead of 1 */
 845         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
 846
 847         reserved = 1 + (nalloc * (data_blocks + ind_blocks));
 848         ap.target = reserved;
 849         error = gfs2_inplace_reserve(ip, &ap);
 850         if (error)
 851                 goto out_alloc;
 852
 853         if (nalloc)
 854                 blocks += gfs2_rg_blocks(ip, reserved) + nalloc * ind_blocks + RES_STATFS;
 855
 856         error = gfs2_trans_begin(sdp, blocks, 0);
 857         if (error)
 858                 goto out_ipres;
 859
 860         for (x = 0; x < num_qd; x++) {
 861                 qd = qda[x];
 862                 offset = qd2offset(qd);
 863                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
 864                 if (error)
 865                         goto out_end_trans;
 866
 867                 do_qc(qd, -qd->qd_change_sync);
 868                 set_bit(QDF_REFRESH, &qd->qd_flags);
 869         }
 870
 871         error = 0;
 872
 873 out_end_trans:
 874         gfs2_trans_end(sdp);
 875 out_ipres:
 876         gfs2_inplace_release(ip);
 877 out_alloc:
 878         gfs2_glock_dq_uninit(&i_gh);
 879 out:
 880         while (qx--)
 881                 gfs2_glock_dq_uninit(&ghs[qx]);
 882         mutex_unlock(&ip->i_inode.i_mutex);
 883         kfree(ghs);
 884         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl, NORMAL_FLUSH);
 885         return error;
 886 }
 887
 888 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
 889 {
 890         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 891         struct gfs2_quota q;
 892         struct gfs2_quota_lvb *qlvb;
 893         loff_t pos;
 894         int error;
 895
 896         memset(&q, 0, sizeof(struct gfs2_quota));
 897         pos = qd2offset(qd);
 898         error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
 899         if (error < 0)
 900                 return error;
 901
 902         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
 903         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
 904         qlvb->__pad = 0;
 905         qlvb->qb_limit = q.qu_limit;
 906         qlvb->qb_warn = q.qu_warn;
 907         qlvb->qb_value = q.qu_value;
 908         qd->qd_qb = *qlvb;
 909
 910         return 0;
 911 }
 912
 913 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 914                     struct gfs2_holder *q_gh)
 915 {
 916         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 917         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 918         struct gfs2_holder i_gh;
 919         int error;
 920
 921 restart:
 922         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 923         if (error)
 924                 return error;
 925
 926         if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
 927                 force_refresh = FORCE;
 928
 929         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
 930
 931         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
 932                 gfs2_glock_dq_uninit(q_gh);
 933                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
 934                                            GL_NOCACHE, q_gh);
 935                 if (error)
 936                         return error;
 937
 938                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
 939                 if (error)
 940                         goto fail;
 941
 942                 error = update_qd(sdp, qd);
 943                 if (error)
 944                         goto fail_gunlock;
 945
 946                 gfs2_glock_dq_uninit(&i_gh);
 947                 gfs2_glock_dq_uninit(q_gh);
 948                 force_refresh = 0;
 949                 goto restart;
 950         }
 951
 952         return 0;
 953
 954 fail_gunlock:
 955         gfs2_glock_dq_uninit(&i_gh);
 956 fail:
 957         gfs2_glock_dq_uninit(q_gh);
 958         return error;
 959 }
 960
 961 int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
 962 {
 963         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 964         struct gfs2_quota_data *qd;
 965         unsigned int x;
 966         int error = 0;
 967
 968         error = gfs2_quota_hold(ip, uid, gid);
 969         if (error)
 970                 return error;
 971
 972         if (capable(CAP_SYS_RESOURCE) ||
 973             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 974                 return 0;
 975
 976         sort(ip->i_res->rs_qa_qd, ip->i_res->rs_qa_qd_num,
 977              sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 978
 979         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
 980                 qd = ip->i_res->rs_qa_qd[x];
 981                 error = do_glock(qd, NO_FORCE, &ip->i_res->rs_qa_qd_ghs[x]);
 982                 if (error)
 983                         break;
 984         }
 985
 986         if (!error)
 987                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
 988         else {
 989                 while (x--)
 990                         gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
 991                 gfs2_quota_unhold(ip);
 992         }
 993
 994         return error;
 995 }
 996
 997 static int need_sync(struct gfs2_quota_data *qd)
 998 {
 999         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1000         struct gfs2_tune *gt = &sdp->sd_tune;
1001         s64 value;
1002         unsigned int num, den;
1003         int do_sync = 1;
1004
1005         if (!qd->qd_qb.qb_limit)
1006                 return 0;
1007
1008         spin_lock(&qd_lock);
1009         value = qd->qd_change;
1010         spin_unlock(&qd_lock);
1011
1012         spin_lock(&gt->gt_spin);
1013         num = gt->gt_quota_scale_num;
1014         den = gt->gt_quota_scale_den;
1015         spin_unlock(&gt->gt_spin);
1016
1017         if (value < 0)
1018                 do_sync = 0;
1019         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
1020                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1021                 do_sync = 0;
1022         else {
1023                 value *= gfs2_jindex_size(sdp) * num;
1024                 value = div_s64(value, den);
1025                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
1026                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1027                         do_sync = 0;
1028         }
1029
1030         return do_sync;
1031 }
1032
1033 void gfs2_quota_unlock(struct gfs2_inode *ip)
1034 {
1035         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1036         struct gfs2_quota_data *qda[4];
1037         unsigned int count = 0;
1038         unsigned int x;
1039         int found;
1040
1041         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1042                 goto out;
1043
1044         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1045                 struct gfs2_quota_data *qd;
1046                 int sync;
1047
1048                 qd = ip->i_res->rs_qa_qd[x];
1049                 sync = need_sync(qd);
1050
1051                 gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
1052                 if (!sync)
1053                         continue;
1054
1055                 spin_lock(&qd_lock);
1056                 found = qd_check_sync(sdp, qd, NULL);
1057                 spin_unlock(&qd_lock);
1058
1059                 if (!found)
1060                         continue;
1061
1062                 gfs2_assert_warn(sdp, qd->qd_change_sync);
1063                 if (bh_get(qd)) {
1064                         clear_bit(QDF_LOCKED, &qd->qd_flags);
1065                         slot_put(qd);
1066                         qd_put(qd);
1067                         continue;
1068                 }
1069
1070                 qda[count++] = qd;
1071         }
1072
1073         if (count) {
1074                 do_sync(count, qda);
1075                 for (x = 0; x < count; x++)
1076                         qd_unlock(qda[x]);
1077         }
1078
1079 out:
1080         gfs2_quota_unhold(ip);
1081 }
1082
1083 #define MAX_LINE 256
1084
1085 static int print_message(struct gfs2_quota_data *qd, char *type)
1086 {
1087         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1088
1089         fs_info(sdp, "quota %s for %s %u\n",
1090                 type,
1091                 (qd->qd_id.type == USRQUOTA) ? "user" : "group",
1092                 from_kqid(&init_user_ns, qd->qd_id));
1093
1094         return 0;
1095 }
1096
1097 /**
1098  * gfs2_quota_check - check if allocating new blocks will exceed quota
1099  * @ip:  The inode for which this check is being performed
1100  * @uid: The uid to check against
1101  * @gid: The gid to check against
1102  * @ap:  The allocation parameters. ap->target contains the requested
1103  *       blocks. ap->min_target, if set, contains the minimum blks
1104  *       requested.
1105  *
1106  * Returns: 0 on success.
1107  *                  min_req = ap->min_target ? ap->min_target : ap->target;
1108  *                  quota must allow atleast min_req blks for success and
1109  *                  ap->allowed is set to the number of blocks allowed
1110  *
1111  *          -EDQUOT otherwise, quota violation. ap->allowed is set to number
1112  *                  of blocks available.
1113  */
1114 int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid,
1115                      struct gfs2_alloc_parms *ap)
1116 {
1117         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1118         struct gfs2_quota_data *qd;
1119         s64 value, warn, limit;
1120         unsigned int x;
1121         int error = 0;
1122
1123         ap->allowed = UINT_MAX; /* Assume we are permitted a whole lot */
1124         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1125                 return 0;
1126
1127         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1128                 return 0;
1129
1130         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1131                 qd = ip->i_res->rs_qa_qd[x];
1132
1133                 if (!(qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1134                       qid_eq(qd->qd_id, make_kqid_gid(gid))))
1135                         continue;
1136
1137                 warn = (s64)be64_to_cpu(qd->qd_qb.qb_warn);
1138                 limit = (s64)be64_to_cpu(qd->qd_qb.qb_limit);
1139                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1140                 spin_lock(&qd_lock);
1141                 value += qd->qd_change;
1142                 spin_unlock(&qd_lock);
1143
1144                 if (limit > 0 && (limit - value) < ap->allowed)
1145                         ap->allowed = limit - value;
1146                 /* If we can't meet the target */
1147                 if (limit && limit < (value + (s64)ap->target)) {
1148                         /* If no min_target specified or we don't meet
1149                          * min_target, return -EDQUOT */
1150                         if (!ap->min_target || ap->min_target > ap->allowed) {
1151                                 print_message(qd, "exceeded");
1152                                 quota_send_warning(qd->qd_id,
1153                                                    sdp->sd_vfs->s_dev,
1154                                                    QUOTA_NL_BHARDWARN);
1155                                 error = -EDQUOT;
1156                                 break;
1157                         }
1158                 } else if (warn && warn < value &&
1159                            time_after_eq(jiffies, qd->qd_last_warn +
1160                                          gfs2_tune_get(sdp, gt_quota_warn_period)
1161                                          * HZ)) {
1162                         quota_send_warning(qd->qd_id,
1163                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1164                         error = print_message(qd, "warning");
1165                         qd->qd_last_warn = jiffies;
1166                 }
1167         }
1168         return error;
1169 }
1170
1171 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1172                        kuid_t uid, kgid_t gid)
1173 {
1174         struct gfs2_quota_data *qd;
1175         unsigned int x;
1176
1177         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1178                 return;
1179         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1180                 return;
1181
1182         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1183                 qd = ip->i_res->rs_qa_qd[x];
1184
1185                 if (qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1186                     qid_eq(qd->qd_id, make_kqid_gid(gid))) {
1187                         do_qc(qd, change);
1188                 }
1189         }
1190 }
1191
1192 int gfs2_quota_sync(struct super_block *sb, int type)
1193 {
1194         struct gfs2_sbd *sdp = sb->s_fs_info;
1195         struct gfs2_quota_data **qda;
1196         unsigned int max_qd = PAGE_SIZE/sizeof(struct gfs2_holder);
1197         unsigned int num_qd;
1198         unsigned int x;
1199         int error = 0;
1200
1201         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1202         if (!qda)
1203                 return -ENOMEM;
1204
1205         mutex_lock(&sdp->sd_quota_sync_mutex);
1206         sdp->sd_quota_sync_gen++;
1207
1208         do {
1209                 num_qd = 0;
1210
1211                 for (;;) {
1212                         error = qd_fish(sdp, qda + num_qd);
1213                         if (error || !qda[num_qd])
1214                                 break;
1215                         if (++num_qd == max_qd)
1216                                 break;
1217                 }
1218
1219                 if (num_qd) {
1220                         if (!error)
1221                                 error = do_sync(num_qd, qda);
1222                         if (!error)
1223                                 for (x = 0; x < num_qd; x++)
1224                                         qda[x]->qd_sync_gen =
1225                                                 sdp->sd_quota_sync_gen;
1226
1227                         for (x = 0; x < num_qd; x++)
1228                                 qd_unlock(qda[x]);
1229                 }
1230         } while (!error && num_qd == max_qd);
1231
1232         mutex_unlock(&sdp->sd_quota_sync_mutex);
1233         kfree(qda);
1234
1235         return error;
1236 }
1237
1238 int gfs2_quota_refresh(struct gfs2_sbd *sdp, struct kqid qid)
1239 {
1240         struct gfs2_quota_data *qd;
1241         struct gfs2_holder q_gh;
1242         int error;
1243
1244         error = qd_get(sdp, qid, &qd);
1245         if (error)
1246                 return error;
1247
1248         error = do_glock(qd, FORCE, &q_gh);
1249         if (!error)
1250                 gfs2_glock_dq_uninit(&q_gh);
1251
1252         qd_put(qd);
1253         return error;
1254 }
1255
1256 int gfs2_quota_init(struct gfs2_sbd *sdp)
1257 {
1258         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1259         u64 size = i_size_read(sdp->sd_qc_inode);
1260         unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1261         unsigned int x, slot = 0;
1262         unsigned int found = 0;
1263         unsigned int hash;
1264         unsigned int bm_size;
1265         u64 dblock;
1266         u32 extlen = 0;
1267         int error;
1268
1269         if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1270                 return -EIO;
1271
1272         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1273         bm_size = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * sizeof(unsigned long));
1274         bm_size *= sizeof(unsigned long);
1275         error = -ENOMEM;
1276         sdp->sd_quota_bitmap = kzalloc(bm_size, GFP_NOFS | __GFP_NOWARN);
1277         if (sdp->sd_quota_bitmap == NULL)
1278                 sdp->sd_quota_bitmap = __vmalloc(bm_size, GFP_NOFS |
1279                                                  __GFP_ZERO, PAGE_KERNEL);
1280         if (!sdp->sd_quota_bitmap)
1281                 return error;
1282
1283         for (x = 0; x < blocks; x++) {
1284                 struct buffer_head *bh;
1285                 const struct gfs2_quota_change *qc;
1286                 unsigned int y;
1287
1288                 if (!extlen) {
1289                         int new = 0;
1290                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1291                         if (error)
1292                                 goto fail;
1293                 }
1294                 error = -EIO;
1295                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1296                 if (!bh)
1297                         goto fail;
1298                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1299                         brelse(bh);
1300                         goto fail;
1301                 }
1302
1303                 qc = (const struct gfs2_quota_change *)(bh->b_data + sizeof(struct gfs2_meta_header));
1304                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1305                      y++, slot++) {
1306                         struct gfs2_quota_data *qd;
1307                         s64 qc_change = be64_to_cpu(qc->qc_change);
1308                         u32 qc_flags = be32_to_cpu(qc->qc_flags);
1309                         enum quota_type qtype = (qc_flags & GFS2_QCF_USER) ?
1310                                                 USRQUOTA : GRPQUOTA;
1311                         struct kqid qc_id = make_kqid(&init_user_ns, qtype,
1312                                                       be32_to_cpu(qc->qc_id));
1313                         qc++;
1314                         if (!qc_change)
1315                                 continue;
1316
1317                         hash = gfs2_qd_hash(sdp, qc_id);
1318                         qd = qd_alloc(hash, sdp, qc_id);
1319                         if (qd == NULL) {
1320                                 brelse(bh);
1321                                 goto fail;
1322                         }
1323
1324                         set_bit(QDF_CHANGE, &qd->qd_flags);
1325                         qd->qd_change = qc_change;
1326                         qd->qd_slot = slot;
1327                         qd->qd_slot_count = 1;
1328
1329                         spin_lock(&qd_lock);
1330                         BUG_ON(test_and_set_bit(slot, sdp->sd_quota_bitmap));
1331                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1332                         atomic_inc(&sdp->sd_quota_count);
1333                         spin_unlock(&qd_lock);
1334
1335                         spin_lock_bucket(hash);
1336                         hlist_bl_add_head_rcu(&qd->qd_hlist, &qd_hash_table[hash]);
1337                         spin_unlock_bucket(hash);
1338
1339                         found++;
1340                 }
1341
1342                 brelse(bh);
1343                 dblock++;
1344                 extlen--;
1345         }
1346
1347         if (found)
1348                 fs_info(sdp, "found %u quota changes\n", found);
1349
1350         return 0;
1351
1352 fail:
1353         gfs2_quota_cleanup(sdp);
1354         return error;
1355 }
1356
1357 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1358 {
1359         struct list_head *head = &sdp->sd_quota_list;
1360         struct gfs2_quota_data *qd;
1361
1362         spin_lock(&qd_lock);
1363         while (!list_empty(head)) {
1364                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1365
1366                 list_del(&qd->qd_list);
1367
1368                 /* Also remove if this qd exists in the reclaim list */
1369                 list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
1370                 atomic_dec(&sdp->sd_quota_count);
1371                 spin_unlock(&qd_lock);
1372
1373                 spin_lock_bucket(qd->qd_hash);
1374                 hlist_bl_del_rcu(&qd->qd_hlist);
1375                 spin_unlock_bucket(qd->qd_hash);
1376
1377                 gfs2_assert_warn(sdp, !qd->qd_change);
1378                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1379                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1380
1381                 gfs2_glock_put(qd->qd_gl);
1382                 call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
1383
1384                 spin_lock(&qd_lock);
1385         }
1386         spin_unlock(&qd_lock);
1387
1388         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1389
1390         kvfree(sdp->sd_quota_bitmap);
1391         sdp->sd_quota_bitmap = NULL;
1392 }
1393
1394 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1395 {
1396         if (error == 0 || error == -EROFS)
1397                 return;
1398         if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1399                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1400 }
1401
1402 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1403                                int (*fxn)(struct super_block *sb, int type),
1404                                unsigned long t, unsigned long *timeo,
1405                                unsigned int *new_timeo)
1406 {
1407         if (t >= *timeo) {
1408                 int error = fxn(sdp->sd_vfs, 0);
1409                 quotad_error(sdp, msg, error);
1410                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1411         } else {
1412                 *timeo -= t;
1413         }
1414 }
1415
1416 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1417 {
1418         struct gfs2_inode *ip;
1419
1420         while(1) {
1421                 ip = NULL;
1422                 spin_lock(&sdp->sd_trunc_lock);
1423                 if (!list_empty(&sdp->sd_trunc_list)) {
1424                         ip = list_entry(sdp->sd_trunc_list.next,
1425                                         struct gfs2_inode, i_trunc_list);
1426                         list_del_init(&ip->i_trunc_list);
1427                 }
1428                 spin_unlock(&sdp->sd_trunc_lock);
1429                 if (ip == NULL)
1430                         return;
1431                 gfs2_glock_finish_truncate(ip);
1432         }
1433 }
1434
1435 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1436         if (!sdp->sd_statfs_force_sync) {
1437                 sdp->sd_statfs_force_sync = 1;
1438                 wake_up(&sdp->sd_quota_wait);
1439         }
1440 }
1441
1442
1443 /**
1444  * gfs2_quotad - Write cached quota changes into the quota file
1445  * @sdp: Pointer to GFS2 superblock
1446  *
1447  */
1448
1449 int gfs2_quotad(void *data)
1450 {
1451         struct gfs2_sbd *sdp = data;
1452         struct gfs2_tune *tune = &sdp->sd_tune;
1453         unsigned long statfs_timeo = 0;
1454         unsigned long quotad_timeo = 0;
1455         unsigned long t = 0;
1456         DEFINE_WAIT(wait);
1457         int empty;
1458
1459         while (!kthread_should_stop()) {
1460
1461                 /* Update the master statfs file */
1462                 if (sdp->sd_statfs_force_sync) {
1463                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1464                         quotad_error(sdp, "statfs", error);
1465                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1466                 }
1467                 else
1468                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1469                                            &statfs_timeo,
1470                                            &tune->gt_statfs_quantum);
1471
1472                 /* Update quota file */
1473                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1474                                    &quotad_timeo, &tune->gt_quota_quantum);
1475
1476                 /* Check for & recover partially truncated inodes */
1477                 quotad_check_trunc_list(sdp);
1478
1479                 try_to_freeze();
1480
1481                 t = min(quotad_timeo, statfs_timeo);
1482
1483                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1484                 spin_lock(&sdp->sd_trunc_lock);
1485                 empty = list_empty(&sdp->sd_trunc_list);
1486                 spin_unlock(&sdp->sd_trunc_lock);
1487                 if (empty && !sdp->sd_statfs_force_sync)
1488                         t -= schedule_timeout(t);
1489                 else
1490                         t = 0;
1491                 finish_wait(&sdp->sd_quota_wait, &wait);
1492         }
1493
1494         return 0;
1495 }
1496
1497 static int gfs2_quota_get_state(struct super_block *sb, struct qc_state *state)
1498 {
1499         struct gfs2_sbd *sdp = sb->s_fs_info;
1500
1501         memset(state, 0, sizeof(*state));
1502
1503         switch (sdp->sd_args.ar_quota) {
1504         case GFS2_QUOTA_ON:
1505                 state->s_state[USRQUOTA].flags |= QCI_LIMITS_ENFORCED;
1506                 state->s_state[GRPQUOTA].flags |= QCI_LIMITS_ENFORCED;
1507                 /*FALLTHRU*/
1508         case GFS2_QUOTA_ACCOUNT:
1509                 state->s_state[USRQUOTA].flags |= QCI_ACCT_ENABLED |
1510                                                   QCI_SYSFILE;
1511                 state->s_state[GRPQUOTA].flags |= QCI_ACCT_ENABLED |
1512                                                   QCI_SYSFILE;
1513                 break;
1514         case GFS2_QUOTA_OFF:
1515                 break;
1516         }
1517         if (sdp->sd_quota_inode) {
1518                 state->s_state[USRQUOTA].ino =
1519                                         GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1520                 state->s_state[USRQUOTA].blocks = sdp->sd_quota_inode->i_blocks;
1521         }
1522         state->s_state[USRQUOTA].nextents = 1;  /* unsupported */
1523         state->s_state[GRPQUOTA] = state->s_state[USRQUOTA];
1524         state->s_incoredqs = list_lru_count(&gfs2_qd_lru);
1525         return 0;
1526 }
1527
1528 static int gfs2_get_dqblk(struct super_block *sb, struct kqid qid,
1529                           struct qc_dqblk *fdq)
1530 {
1531         struct gfs2_sbd *sdp = sb->s_fs_info;
1532         struct gfs2_quota_lvb *qlvb;
1533         struct gfs2_quota_data *qd;
1534         struct gfs2_holder q_gh;
1535         int error;
1536
1537         memset(fdq, 0, sizeof(*fdq));
1538
1539         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1540                 return -ESRCH; /* Crazy XFS error code */
1541
1542         if ((qid.type != USRQUOTA) &&
1543             (qid.type != GRPQUOTA))
1544                 return -EINVAL;
1545
1546         error = qd_get(sdp, qid, &qd);
1547         if (error)
1548                 return error;
1549         error = do_glock(qd, FORCE, &q_gh);
1550         if (error)
1551                 goto out;
1552
1553         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1554         fdq->d_spc_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_sb.sb_bsize_shift;
1555         fdq->d_spc_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_sb.sb_bsize_shift;
1556         fdq->d_space = be64_to_cpu(qlvb->qb_value) << sdp->sd_sb.sb_bsize_shift;
1557
1558         gfs2_glock_dq_uninit(&q_gh);
1559 out:
1560         qd_put(qd);
1561         return error;
1562 }
1563
1564 /* GFS2 only supports a subset of the XFS fields */
1565 #define GFS2_FIELDMASK (QC_SPC_SOFT|QC_SPC_HARD|QC_SPACE)
1566
1567 static int gfs2_set_dqblk(struct super_block *sb, struct kqid qid,
1568                           struct qc_dqblk *fdq)
1569 {
1570         struct gfs2_sbd *sdp = sb->s_fs_info;
1571         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1572         struct gfs2_quota_data *qd;
1573         struct gfs2_holder q_gh, i_gh;
1574         unsigned int data_blocks, ind_blocks;
1575         unsigned int blocks = 0;
1576         int alloc_required;
1577         loff_t offset;
1578         int error;
1579
1580         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1581                 return -ESRCH; /* Crazy XFS error code */
1582
1583         if ((qid.type != USRQUOTA) &&
1584             (qid.type != GRPQUOTA))
1585                 return -EINVAL;
1586
1587         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1588                 return -EINVAL;
1589
1590         error = qd_get(sdp, qid, &qd);
1591         if (error)
1592                 return error;
1593
1594         error = gfs2_rs_alloc(ip);
1595         if (error)
1596                 goto out_put;
1597
1598         mutex_lock(&ip->i_inode.i_mutex);
1599         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1600         if (error)
1601                 goto out_unlockput;
1602         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1603         if (error)
1604                 goto out_q;
1605
1606         /* Check for existing entry, if none then alloc new blocks */
1607         error = update_qd(sdp, qd);
1608         if (error)
1609                 goto out_i;
1610
1611         /* If nothing has changed, this is a no-op */
1612         if ((fdq->d_fieldmask & QC_SPC_SOFT) &&
1613             ((fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1614                 fdq->d_fieldmask ^= QC_SPC_SOFT;
1615
1616         if ((fdq->d_fieldmask & QC_SPC_HARD) &&
1617             ((fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1618                 fdq->d_fieldmask ^= QC_SPC_HARD;
1619
1620         if ((fdq->d_fieldmask & QC_SPACE) &&
1621             ((fdq->d_space >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1622                 fdq->d_fieldmask ^= QC_SPACE;
1623
1624         if (fdq->d_fieldmask == 0)
1625                 goto out_i;
1626
1627         offset = qd2offset(qd);
1628         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1629         if (gfs2_is_stuffed(ip))
1630                 alloc_required = 1;
1631         if (alloc_required) {
1632                 struct gfs2_alloc_parms ap = { .aflags = 0, };
1633                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1634                                        &data_blocks, &ind_blocks);
1635                 blocks = 1 + data_blocks + ind_blocks;
1636                 ap.target = blocks;
1637                 error = gfs2_inplace_reserve(ip, &ap);
1638                 if (error)
1639                         goto out_i;
1640                 blocks += gfs2_rg_blocks(ip, blocks);
1641         }
1642
1643         /* Some quotas span block boundaries and can update two blocks,
1644            adding an extra block to the transaction to handle such quotas */
1645         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1646         if (error)
1647                 goto out_release;
1648
1649         /* Apply changes */
1650         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1651
1652         gfs2_trans_end(sdp);
1653 out_release:
1654         if (alloc_required)
1655                 gfs2_inplace_release(ip);
1656 out_i:
1657         gfs2_glock_dq_uninit(&i_gh);
1658 out_q:
1659         gfs2_glock_dq_uninit(&q_gh);
1660 out_unlockput:
1661         mutex_unlock(&ip->i_inode.i_mutex);
1662 out_put:
1663         qd_put(qd);
1664         return error;
1665 }
1666
1667 const struct quotactl_ops gfs2_quotactl_ops = {
1668         .quota_sync     = gfs2_quota_sync,
1669         .get_state      = gfs2_quota_get_state,
1670         .get_dqblk      = gfs2_get_dqblk,
1671         .set_dqblk      = gfs2_set_dqblk,
1672 };
1673
1674 void __init gfs2_quota_hash_init(void)
1675 {
1676         unsigned i;
1677
1678         for(i = 0; i < GFS2_QD_HASH_SIZE; i++)
1679                 INIT_HLIST_BL_HEAD(&qd_hash_table[i]);
1680 }