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       BIT(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 = BIT(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, 0, &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 (sb_rdonly(sdp->sd_vfs))
 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 /**
 531  * gfs2_qa_alloc - make sure we have a quota allocations data structure,
 532  *                 if necessary
 533  * @ip: the inode for this reservation
 534  */
 535 int gfs2_qa_alloc(struct gfs2_inode *ip)
 536 {
 537         int error = 0;
 538         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 539
 540         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 541                 return 0;
 542
 543         down_write(&ip->i_rw_mutex);
 544         if (ip->i_qadata == NULL) {
 545                 ip->i_qadata = kmem_cache_zalloc(gfs2_qadata_cachep, GFP_NOFS);
 546                 if (!ip->i_qadata)
 547                         error = -ENOMEM;
 548         }
 549         up_write(&ip->i_rw_mutex);
 550         return error;
 551 }
 552
 553 void gfs2_qa_delete(struct gfs2_inode *ip, atomic_t *wcount)
 554 {
 555         down_write(&ip->i_rw_mutex);
 556         if (ip->i_qadata && ((wcount == NULL) || (atomic_read(wcount) <= 1))) {
 557                 kmem_cache_free(gfs2_qadata_cachep, ip->i_qadata);
 558                 ip->i_qadata = NULL;
 559         }
 560         up_write(&ip->i_rw_mutex);
 561 }
 562
 563 int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
 564 {
 565         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 566         struct gfs2_quota_data **qd;
 567         int error;
 568
 569         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 570                 return 0;
 571
 572         if (ip->i_qadata == NULL) {
 573                 error = gfs2_rsqa_alloc(ip);
 574                 if (error)
 575                         return error;
 576         }
 577
 578         qd = ip->i_qadata->qa_qd;
 579
 580         if (gfs2_assert_warn(sdp, !ip->i_qadata->qa_qd_num) ||
 581             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
 582                 return -EIO;
 583
 584         error = qdsb_get(sdp, make_kqid_uid(ip->i_inode.i_uid), qd);
 585         if (error)
 586                 goto out;
 587         ip->i_qadata->qa_qd_num++;
 588         qd++;
 589
 590         error = qdsb_get(sdp, make_kqid_gid(ip->i_inode.i_gid), qd);
 591         if (error)
 592                 goto out;
 593         ip->i_qadata->qa_qd_num++;
 594         qd++;
 595
 596         if (!uid_eq(uid, NO_UID_QUOTA_CHANGE) &&
 597             !uid_eq(uid, ip->i_inode.i_uid)) {
 598                 error = qdsb_get(sdp, make_kqid_uid(uid), qd);
 599                 if (error)
 600                         goto out;
 601                 ip->i_qadata->qa_qd_num++;
 602                 qd++;
 603         }
 604
 605         if (!gid_eq(gid, NO_GID_QUOTA_CHANGE) &&
 606             !gid_eq(gid, ip->i_inode.i_gid)) {
 607                 error = qdsb_get(sdp, make_kqid_gid(gid), qd);
 608                 if (error)
 609                         goto out;
 610                 ip->i_qadata->qa_qd_num++;
 611                 qd++;
 612         }
 613
 614 out:
 615         if (error)
 616                 gfs2_quota_unhold(ip);
 617         return error;
 618 }
 619
 620 void gfs2_quota_unhold(struct gfs2_inode *ip)
 621 {
 622         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 623         u32 x;
 624
 625         if (ip->i_qadata == NULL)
 626                 return;
 627         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 628
 629         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
 630                 qdsb_put(ip->i_qadata->qa_qd[x]);
 631                 ip->i_qadata->qa_qd[x] = NULL;
 632         }
 633         ip->i_qadata->qa_qd_num = 0;
 634 }
 635
 636 static int sort_qd(const void *a, const void *b)
 637 {
 638         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
 639         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
 640
 641         if (qid_lt(qd_a->qd_id, qd_b->qd_id))
 642                 return -1;
 643         if (qid_lt(qd_b->qd_id, qd_a->qd_id))
 644                 return 1;
 645         return 0;
 646 }
 647
 648 static void do_qc(struct gfs2_quota_data *qd, s64 change)
 649 {
 650         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
 651         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 652         struct gfs2_quota_change *qc = qd->qd_bh_qc;
 653         s64 x;
 654
 655         mutex_lock(&sdp->sd_quota_mutex);
 656         gfs2_trans_add_meta(ip->i_gl, qd->qd_bh);
 657
 658         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
 659                 qc->qc_change = 0;
 660                 qc->qc_flags = 0;
 661                 if (qd->qd_id.type == USRQUOTA)
 662                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
 663                 qc->qc_id = cpu_to_be32(from_kqid(&init_user_ns, qd->qd_id));
 664         }
 665
 666         x = be64_to_cpu(qc->qc_change) + change;
 667         qc->qc_change = cpu_to_be64(x);
 668
 669         spin_lock(&qd_lock);
 670         qd->qd_change = x;
 671         spin_unlock(&qd_lock);
 672
 673         if (!x) {
 674                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
 675                 clear_bit(QDF_CHANGE, &qd->qd_flags);
 676                 qc->qc_flags = 0;
 677                 qc->qc_id = 0;
 678                 slot_put(qd);
 679                 qd_put(qd);
 680         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
 681                 qd_hold(qd);
 682                 slot_hold(qd);
 683         }
 684
 685         if (change < 0) /* Reset quiet flag if we freed some blocks */
 686                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
 687         mutex_unlock(&sdp->sd_quota_mutex);
 688 }
 689
 690 static int gfs2_write_buf_to_page(struct gfs2_inode *ip, unsigned long index,
 691                                   unsigned off, void *buf, unsigned bytes)
 692 {
 693         struct inode *inode = &ip->i_inode;
 694         struct gfs2_sbd *sdp = GFS2_SB(inode);
 695         struct address_space *mapping = inode->i_mapping;
 696         struct page *page;
 697         struct buffer_head *bh;
 698         void *kaddr;
 699         u64 blk;
 700         unsigned bsize = sdp->sd_sb.sb_bsize, bnum = 0, boff = 0;
 701         unsigned to_write = bytes, pg_off = off;
 702         int done = 0;
 703
 704         blk = index << (PAGE_SHIFT - sdp->sd_sb.sb_bsize_shift);
 705         boff = off % bsize;
 706
 707         page = find_or_create_page(mapping, index, GFP_NOFS);
 708         if (!page)
 709                 return -ENOMEM;
 710         if (!page_has_buffers(page))
 711                 create_empty_buffers(page, bsize, 0);
 712
 713         bh = page_buffers(page);
 714         while (!done) {
 715                 /* Find the beginning block within the page */
 716                 if (pg_off >= ((bnum * bsize) + bsize)) {
 717                         bh = bh->b_this_page;
 718                         bnum++;
 719                         blk++;
 720                         continue;
 721                 }
 722                 if (!buffer_mapped(bh)) {
 723                         gfs2_block_map(inode, blk, bh, 1);
 724                         if (!buffer_mapped(bh))
 725                                 goto unlock_out;
 726                         /* If it's a newly allocated disk block, zero it */
 727                         if (buffer_new(bh))
 728                                 zero_user(page, bnum * bsize, bh->b_size);
 729                 }
 730                 if (PageUptodate(page))
 731                         set_buffer_uptodate(bh);
 732                 if (!buffer_uptodate(bh)) {
 733                         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &bh);
 734                         wait_on_buffer(bh);
 735                         if (!buffer_uptodate(bh))
 736                                 goto unlock_out;
 737                 }
 738                 gfs2_trans_add_data(ip->i_gl, bh);
 739
 740                 /* If we need to write to the next block as well */
 741                 if (to_write > (bsize - boff)) {
 742                         pg_off += (bsize - boff);
 743                         to_write -= (bsize - boff);
 744                         boff = pg_off % bsize;
 745                         continue;
 746                 }
 747                 done = 1;
 748         }
 749
 750         /* Write to the page, now that we have setup the buffer(s) */
 751         kaddr = kmap_atomic(page);
 752         memcpy(kaddr + off, buf, bytes);
 753         flush_dcache_page(page);
 754         kunmap_atomic(kaddr);
 755         unlock_page(page);
 756         put_page(page);
 757
 758         return 0;
 759
 760 unlock_out:
 761         unlock_page(page);
 762         put_page(page);
 763         return -EIO;
 764 }
 765
 766 static int gfs2_write_disk_quota(struct gfs2_inode *ip, struct gfs2_quota *qp,
 767                                  loff_t loc)
 768 {
 769         unsigned long pg_beg;
 770         unsigned pg_off, nbytes, overflow = 0;
 771         int pg_oflow = 0, error;
 772         void *ptr;
 773
 774         nbytes = sizeof(struct gfs2_quota);
 775
 776         pg_beg = loc >> PAGE_SHIFT;
 777         pg_off = loc % PAGE_SIZE;
 778
 779         /* If the quota straddles a page boundary, split the write in two */
 780         if ((pg_off + nbytes) > PAGE_SIZE) {
 781                 pg_oflow = 1;
 782                 overflow = (pg_off + nbytes) - PAGE_SIZE;
 783         }
 784
 785         ptr = qp;
 786         error = gfs2_write_buf_to_page(ip, pg_beg, pg_off, ptr,
 787                                        nbytes - overflow);
 788         /* If there's an overflow, write the remaining bytes to the next page */
 789         if (!error && pg_oflow)
 790                 error = gfs2_write_buf_to_page(ip, pg_beg + 1, 0,
 791                                                ptr + nbytes - overflow,
 792                                                overflow);
 793         return error;
 794 }
 795
 796 /**
 797  * gfs2_adjust_quota - adjust record of current block usage
 798  * @ip: The quota inode
 799  * @loc: Offset of the entry in the quota file
 800  * @change: The amount of usage change to record
 801  * @qd: The quota data
 802  * @fdq: The updated limits to record
 803  *
 804  * This function was mostly borrowed from gfs2_block_truncate_page which was
 805  * in turn mostly borrowed from ext3
 806  *
 807  * Returns: 0 or -ve on error
 808  */
 809
 810 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 811                              s64 change, struct gfs2_quota_data *qd,
 812                              struct qc_dqblk *fdq)
 813 {
 814         struct inode *inode = &ip->i_inode;
 815         struct gfs2_sbd *sdp = GFS2_SB(inode);
 816         struct gfs2_quota q;
 817         int err;
 818         u64 size;
 819
 820         if (gfs2_is_stuffed(ip)) {
 821                 err = gfs2_unstuff_dinode(ip, NULL);
 822                 if (err)
 823                         return err;
 824         }
 825
 826         memset(&q, 0, sizeof(struct gfs2_quota));
 827         err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
 828         if (err < 0)
 829                 return err;
 830
 831         loc -= sizeof(q); /* gfs2_internal_read would've advanced the loc ptr */
 832         err = -EIO;
 833         be64_add_cpu(&q.qu_value, change);
 834         if (((s64)be64_to_cpu(q.qu_value)) < 0)
 835                 q.qu_value = 0; /* Never go negative on quota usage */
 836         qd->qd_qb.qb_value = q.qu_value;
 837         if (fdq) {
 838                 if (fdq->d_fieldmask & QC_SPC_SOFT) {
 839                         q.qu_warn = cpu_to_be64(fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift);
 840                         qd->qd_qb.qb_warn = q.qu_warn;
 841                 }
 842                 if (fdq->d_fieldmask & QC_SPC_HARD) {
 843                         q.qu_limit = cpu_to_be64(fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift);
 844                         qd->qd_qb.qb_limit = q.qu_limit;
 845                 }
 846                 if (fdq->d_fieldmask & QC_SPACE) {
 847                         q.qu_value = cpu_to_be64(fdq->d_space >> sdp->sd_sb.sb_bsize_shift);
 848                         qd->qd_qb.qb_value = q.qu_value;
 849                 }
 850         }
 851
 852         err = gfs2_write_disk_quota(ip, &q, loc);
 853         if (!err) {
 854                 size = loc + sizeof(struct gfs2_quota);
 855                 if (size > inode->i_size)
 856                         i_size_write(inode, size);
 857                 inode->i_mtime = inode->i_atime = current_time(inode);
 858                 mark_inode_dirty(inode);
 859                 set_bit(QDF_REFRESH, &qd->qd_flags);
 860         }
 861
 862         return err;
 863 }
 864
 865 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 866 {
 867         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_name.ln_sbd;
 868         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 869         struct gfs2_alloc_parms ap = { .aflags = 0, };
 870         unsigned int data_blocks, ind_blocks;
 871         struct gfs2_holder *ghs, i_gh;
 872         unsigned int qx, x;
 873         struct gfs2_quota_data *qd;
 874         unsigned reserved;
 875         loff_t offset;
 876         unsigned int nalloc = 0, blocks;
 877         int error;
 878
 879         error = gfs2_rsqa_alloc(ip);
 880         if (error)
 881                 return error;
 882
 883         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 884                               &data_blocks, &ind_blocks);
 885
 886         ghs = kmalloc(num_qd * sizeof(struct gfs2_holder), GFP_NOFS);
 887         if (!ghs)
 888                 return -ENOMEM;
 889
 890         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 891         inode_lock(&ip->i_inode);
 892         for (qx = 0; qx < num_qd; qx++) {
 893                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
 894                                            GL_NOCACHE, &ghs[qx]);
 895                 if (error)
 896                         goto out;
 897         }
 898
 899         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 900         if (error)
 901                 goto out;
 902
 903         for (x = 0; x < num_qd; x++) {
 904                 offset = qd2offset(qda[x]);
 905                 if (gfs2_write_alloc_required(ip, offset,
 906                                               sizeof(struct gfs2_quota)))
 907                         nalloc++;
 908         }
 909
 910         /*
 911          * 1 blk for unstuffing inode if stuffed. We add this extra
 912          * block to the reservation unconditionally. If the inode
 913          * doesn't need unstuffing, the block will be released to the
 914          * rgrp since it won't be allocated during the transaction
 915          */
 916         /* +3 in the end for unstuffing block, inode size update block
 917          * and another block in case quota straddles page boundary and
 918          * two blocks need to be updated instead of 1 */
 919         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
 920
 921         reserved = 1 + (nalloc * (data_blocks + ind_blocks));
 922         ap.target = reserved;
 923         error = gfs2_inplace_reserve(ip, &ap);
 924         if (error)
 925                 goto out_alloc;
 926
 927         if (nalloc)
 928                 blocks += gfs2_rg_blocks(ip, reserved) + nalloc * ind_blocks + RES_STATFS;
 929
 930         error = gfs2_trans_begin(sdp, blocks, 0);
 931         if (error)
 932                 goto out_ipres;
 933
 934         for (x = 0; x < num_qd; x++) {
 935                 qd = qda[x];
 936                 offset = qd2offset(qd);
 937                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
 938                 if (error)
 939                         goto out_end_trans;
 940
 941                 do_qc(qd, -qd->qd_change_sync);
 942                 set_bit(QDF_REFRESH, &qd->qd_flags);
 943         }
 944
 945         error = 0;
 946
 947 out_end_trans:
 948         gfs2_trans_end(sdp);
 949 out_ipres:
 950         gfs2_inplace_release(ip);
 951 out_alloc:
 952         gfs2_glock_dq_uninit(&i_gh);
 953 out:
 954         while (qx--)
 955                 gfs2_glock_dq_uninit(&ghs[qx]);
 956         inode_unlock(&ip->i_inode);
 957         kfree(ghs);
 958         gfs2_log_flush(ip->i_gl->gl_name.ln_sbd, ip->i_gl, NORMAL_FLUSH);
 959         return error;
 960 }
 961
 962 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
 963 {
 964         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 965         struct gfs2_quota q;
 966         struct gfs2_quota_lvb *qlvb;
 967         loff_t pos;
 968         int error;
 969
 970         memset(&q, 0, sizeof(struct gfs2_quota));
 971         pos = qd2offset(qd);
 972         error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
 973         if (error < 0)
 974                 return error;
 975
 976         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
 977         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
 978         qlvb->__pad = 0;
 979         qlvb->qb_limit = q.qu_limit;
 980         qlvb->qb_warn = q.qu_warn;
 981         qlvb->qb_value = q.qu_value;
 982         qd->qd_qb = *qlvb;
 983
 984         return 0;
 985 }
 986
 987 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 988                     struct gfs2_holder *q_gh)
 989 {
 990         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
 991         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 992         struct gfs2_holder i_gh;
 993         int error;
 994
 995 restart:
 996         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 997         if (error)
 998                 return error;
 999
1000         if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
1001                 force_refresh = FORCE;
1002
1003         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1004
1005         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
1006                 gfs2_glock_dq_uninit(q_gh);
1007                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
1008                                            GL_NOCACHE, q_gh);
1009                 if (error)
1010                         return error;
1011
1012                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
1013                 if (error)
1014                         goto fail;
1015
1016                 error = update_qd(sdp, qd);
1017                 if (error)
1018                         goto fail_gunlock;
1019
1020                 gfs2_glock_dq_uninit(&i_gh);
1021                 gfs2_glock_dq_uninit(q_gh);
1022                 force_refresh = 0;
1023                 goto restart;
1024         }
1025
1026         return 0;
1027
1028 fail_gunlock:
1029         gfs2_glock_dq_uninit(&i_gh);
1030 fail:
1031         gfs2_glock_dq_uninit(q_gh);
1032         return error;
1033 }
1034
1035 int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
1036 {
1037         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1038         struct gfs2_quota_data *qd;
1039         u32 x;
1040         int error = 0;
1041
1042         if (capable(CAP_SYS_RESOURCE) ||
1043             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1044                 return 0;
1045
1046         error = gfs2_quota_hold(ip, uid, gid);
1047         if (error)
1048                 return error;
1049
1050         sort(ip->i_qadata->qa_qd, ip->i_qadata->qa_qd_num,
1051              sizeof(struct gfs2_quota_data *), sort_qd, NULL);
1052
1053         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1054                 qd = ip->i_qadata->qa_qd[x];
1055                 error = do_glock(qd, NO_FORCE, &ip->i_qadata->qa_qd_ghs[x]);
1056                 if (error)
1057                         break;
1058         }
1059
1060         if (!error)
1061                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
1062         else {
1063                 while (x--)
1064                         gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
1065                 gfs2_quota_unhold(ip);
1066         }
1067
1068         return error;
1069 }
1070
1071 static int need_sync(struct gfs2_quota_data *qd)
1072 {
1073         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1074         struct gfs2_tune *gt = &sdp->sd_tune;
1075         s64 value;
1076         unsigned int num, den;
1077         int do_sync = 1;
1078
1079         if (!qd->qd_qb.qb_limit)
1080                 return 0;
1081
1082         spin_lock(&qd_lock);
1083         value = qd->qd_change;
1084         spin_unlock(&qd_lock);
1085
1086         spin_lock(&gt->gt_spin);
1087         num = gt->gt_quota_scale_num;
1088         den = gt->gt_quota_scale_den;
1089         spin_unlock(&gt->gt_spin);
1090
1091         if (value < 0)
1092                 do_sync = 0;
1093         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
1094                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1095                 do_sync = 0;
1096         else {
1097                 value *= gfs2_jindex_size(sdp) * num;
1098                 value = div_s64(value, den);
1099                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
1100                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1101                         do_sync = 0;
1102         }
1103
1104         return do_sync;
1105 }
1106
1107 void gfs2_quota_unlock(struct gfs2_inode *ip)
1108 {
1109         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1110         struct gfs2_quota_data *qda[4];
1111         unsigned int count = 0;
1112         u32 x;
1113         int found;
1114
1115         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1116                 goto out;
1117
1118         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1119                 struct gfs2_quota_data *qd;
1120                 int sync;
1121
1122                 qd = ip->i_qadata->qa_qd[x];
1123                 sync = need_sync(qd);
1124
1125                 gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
1126                 if (!sync)
1127                         continue;
1128
1129                 spin_lock(&qd_lock);
1130                 found = qd_check_sync(sdp, qd, NULL);
1131                 spin_unlock(&qd_lock);
1132
1133                 if (!found)
1134                         continue;
1135
1136                 gfs2_assert_warn(sdp, qd->qd_change_sync);
1137                 if (bh_get(qd)) {
1138                         clear_bit(QDF_LOCKED, &qd->qd_flags);
1139                         slot_put(qd);
1140                         qd_put(qd);
1141                         continue;
1142                 }
1143
1144                 qda[count++] = qd;
1145         }
1146
1147         if (count) {
1148                 do_sync(count, qda);
1149                 for (x = 0; x < count; x++)
1150                         qd_unlock(qda[x]);
1151         }
1152
1153 out:
1154         gfs2_quota_unhold(ip);
1155 }
1156
1157 #define MAX_LINE 256
1158
1159 static int print_message(struct gfs2_quota_data *qd, char *type)
1160 {
1161         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1162
1163         fs_info(sdp, "quota %s for %s %u\n",
1164                 type,
1165                 (qd->qd_id.type == USRQUOTA) ? "user" : "group",
1166                 from_kqid(&init_user_ns, qd->qd_id));
1167
1168         return 0;
1169 }
1170
1171 /**
1172  * gfs2_quota_check - check if allocating new blocks will exceed quota
1173  * @ip:  The inode for which this check is being performed
1174  * @uid: The uid to check against
1175  * @gid: The gid to check against
1176  * @ap:  The allocation parameters. ap->target contains the requested
1177  *       blocks. ap->min_target, if set, contains the minimum blks
1178  *       requested.
1179  *
1180  * Returns: 0 on success.
1181  *                  min_req = ap->min_target ? ap->min_target : ap->target;
1182  *                  quota must allow atleast min_req blks for success and
1183  *                  ap->allowed is set to the number of blocks allowed
1184  *
1185  *          -EDQUOT otherwise, quota violation. ap->allowed is set to number
1186  *                  of blocks available.
1187  */
1188 int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid,
1189                      struct gfs2_alloc_parms *ap)
1190 {
1191         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1192         struct gfs2_quota_data *qd;
1193         s64 value, warn, limit;
1194         u32 x;
1195         int error = 0;
1196
1197         ap->allowed = UINT_MAX; /* Assume we are permitted a whole lot */
1198         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1199                 return 0;
1200
1201         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1202                 return 0;
1203
1204         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1205                 qd = ip->i_qadata->qa_qd[x];
1206
1207                 if (!(qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1208                       qid_eq(qd->qd_id, make_kqid_gid(gid))))
1209                         continue;
1210
1211                 warn = (s64)be64_to_cpu(qd->qd_qb.qb_warn);
1212                 limit = (s64)be64_to_cpu(qd->qd_qb.qb_limit);
1213                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1214                 spin_lock(&qd_lock);
1215                 value += qd->qd_change;
1216                 spin_unlock(&qd_lock);
1217
1218                 if (limit > 0 && (limit - value) < ap->allowed)
1219                         ap->allowed = limit - value;
1220                 /* If we can't meet the target */
1221                 if (limit && limit < (value + (s64)ap->target)) {
1222                         /* If no min_target specified or we don't meet
1223                          * min_target, return -EDQUOT */
1224                         if (!ap->min_target || ap->min_target > ap->allowed) {
1225                                 if (!test_and_set_bit(QDF_QMSG_QUIET,
1226                                                       &qd->qd_flags)) {
1227                                         print_message(qd, "exceeded");
1228                                         quota_send_warning(qd->qd_id,
1229                                                            sdp->sd_vfs->s_dev,
1230                                                            QUOTA_NL_BHARDWARN);
1231                                 }
1232                                 error = -EDQUOT;
1233                                 break;
1234                         }
1235                 } else if (warn && warn < value &&
1236                            time_after_eq(jiffies, qd->qd_last_warn +
1237                                          gfs2_tune_get(sdp, gt_quota_warn_period)
1238                                          * HZ)) {
1239                         quota_send_warning(qd->qd_id,
1240                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1241                         error = print_message(qd, "warning");
1242                         qd->qd_last_warn = jiffies;
1243                 }
1244         }
1245         return error;
1246 }
1247
1248 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1249                        kuid_t uid, kgid_t gid)
1250 {
1251         struct gfs2_quota_data *qd;
1252         u32 x;
1253         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1254
1255         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON ||
1256             gfs2_assert_warn(sdp, change))
1257                 return;
1258         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1259                 return;
1260
1261         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1262                 qd = ip->i_qadata->qa_qd[x];
1263
1264                 if (qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1265                     qid_eq(qd->qd_id, make_kqid_gid(gid))) {
1266                         do_qc(qd, change);
1267                 }
1268         }
1269 }
1270
1271 int gfs2_quota_sync(struct super_block *sb, int type)
1272 {
1273         struct gfs2_sbd *sdp = sb->s_fs_info;
1274         struct gfs2_quota_data **qda;
1275         unsigned int max_qd = PAGE_SIZE/sizeof(struct gfs2_holder);
1276         unsigned int num_qd;
1277         unsigned int x;
1278         int error = 0;
1279
1280         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1281         if (!qda)
1282                 return -ENOMEM;
1283
1284         mutex_lock(&sdp->sd_quota_sync_mutex);
1285         sdp->sd_quota_sync_gen++;
1286
1287         do {
1288                 num_qd = 0;
1289
1290                 for (;;) {
1291                         error = qd_fish(sdp, qda + num_qd);
1292                         if (error || !qda[num_qd])
1293                                 break;
1294                         if (++num_qd == max_qd)
1295                                 break;
1296                 }
1297
1298                 if (num_qd) {
1299                         if (!error)
1300                                 error = do_sync(num_qd, qda);
1301                         if (!error)
1302                                 for (x = 0; x < num_qd; x++)
1303                                         qda[x]->qd_sync_gen =
1304                                                 sdp->sd_quota_sync_gen;
1305
1306                         for (x = 0; x < num_qd; x++)
1307                                 qd_unlock(qda[x]);
1308                 }
1309         } while (!error && num_qd == max_qd);
1310
1311         mutex_unlock(&sdp->sd_quota_sync_mutex);
1312         kfree(qda);
1313
1314         return error;
1315 }
1316
1317 int gfs2_quota_refresh(struct gfs2_sbd *sdp, struct kqid qid)
1318 {
1319         struct gfs2_quota_data *qd;
1320         struct gfs2_holder q_gh;
1321         int error;
1322
1323         error = qd_get(sdp, qid, &qd);
1324         if (error)
1325                 return error;
1326
1327         error = do_glock(qd, FORCE, &q_gh);
1328         if (!error)
1329                 gfs2_glock_dq_uninit(&q_gh);
1330
1331         qd_put(qd);
1332         return error;
1333 }
1334
1335 int gfs2_quota_init(struct gfs2_sbd *sdp)
1336 {
1337         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1338         u64 size = i_size_read(sdp->sd_qc_inode);
1339         unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1340         unsigned int x, slot = 0;
1341         unsigned int found = 0;
1342         unsigned int hash;
1343         unsigned int bm_size;
1344         u64 dblock;
1345         u32 extlen = 0;
1346         int error;
1347
1348         if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1349                 return -EIO;
1350
1351         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1352         bm_size = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * sizeof(unsigned long));
1353         bm_size *= sizeof(unsigned long);
1354         error = -ENOMEM;
1355         sdp->sd_quota_bitmap = kzalloc(bm_size, GFP_NOFS | __GFP_NOWARN);
1356         if (sdp->sd_quota_bitmap == NULL)
1357                 sdp->sd_quota_bitmap = __vmalloc(bm_size, GFP_NOFS |
1358                                                  __GFP_ZERO, PAGE_KERNEL);
1359         if (!sdp->sd_quota_bitmap)
1360                 return error;
1361
1362         for (x = 0; x < blocks; x++) {
1363                 struct buffer_head *bh;
1364                 const struct gfs2_quota_change *qc;
1365                 unsigned int y;
1366
1367                 if (!extlen) {
1368                         int new = 0;
1369                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1370                         if (error)
1371                                 goto fail;
1372                 }
1373                 error = -EIO;
1374                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1375                 if (!bh)
1376                         goto fail;
1377                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1378                         brelse(bh);
1379                         goto fail;
1380                 }
1381
1382                 qc = (const struct gfs2_quota_change *)(bh->b_data + sizeof(struct gfs2_meta_header));
1383                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1384                      y++, slot++) {
1385                         struct gfs2_quota_data *qd;
1386                         s64 qc_change = be64_to_cpu(qc->qc_change);
1387                         u32 qc_flags = be32_to_cpu(qc->qc_flags);
1388                         enum quota_type qtype = (qc_flags & GFS2_QCF_USER) ?
1389                                                 USRQUOTA : GRPQUOTA;
1390                         struct kqid qc_id = make_kqid(&init_user_ns, qtype,
1391                                                       be32_to_cpu(qc->qc_id));
1392                         qc++;
1393                         if (!qc_change)
1394                                 continue;
1395
1396                         hash = gfs2_qd_hash(sdp, qc_id);
1397                         qd = qd_alloc(hash, sdp, qc_id);
1398                         if (qd == NULL) {
1399                                 brelse(bh);
1400                                 goto fail;
1401                         }
1402
1403                         set_bit(QDF_CHANGE, &qd->qd_flags);
1404                         qd->qd_change = qc_change;
1405                         qd->qd_slot = slot;
1406                         qd->qd_slot_count = 1;
1407
1408                         spin_lock(&qd_lock);
1409                         BUG_ON(test_and_set_bit(slot, sdp->sd_quota_bitmap));
1410                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1411                         atomic_inc(&sdp->sd_quota_count);
1412                         spin_unlock(&qd_lock);
1413
1414                         spin_lock_bucket(hash);
1415                         hlist_bl_add_head_rcu(&qd->qd_hlist, &qd_hash_table[hash]);
1416                         spin_unlock_bucket(hash);
1417
1418                         found++;
1419                 }
1420
1421                 brelse(bh);
1422                 dblock++;
1423                 extlen--;
1424         }
1425
1426         if (found)
1427                 fs_info(sdp, "found %u quota changes\n", found);
1428
1429         return 0;
1430
1431 fail:
1432         gfs2_quota_cleanup(sdp);
1433         return error;
1434 }
1435
1436 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1437 {
1438         struct list_head *head = &sdp->sd_quota_list;
1439         struct gfs2_quota_data *qd;
1440
1441         spin_lock(&qd_lock);
1442         while (!list_empty(head)) {
1443                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1444
1445                 list_del(&qd->qd_list);
1446
1447                 /* Also remove if this qd exists in the reclaim list */
1448                 list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
1449                 atomic_dec(&sdp->sd_quota_count);
1450                 spin_unlock(&qd_lock);
1451
1452                 spin_lock_bucket(qd->qd_hash);
1453                 hlist_bl_del_rcu(&qd->qd_hlist);
1454                 spin_unlock_bucket(qd->qd_hash);
1455
1456                 gfs2_assert_warn(sdp, !qd->qd_change);
1457                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1458                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1459
1460                 gfs2_glock_put(qd->qd_gl);
1461                 call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
1462
1463                 spin_lock(&qd_lock);
1464         }
1465         spin_unlock(&qd_lock);
1466
1467         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1468
1469         kvfree(sdp->sd_quota_bitmap);
1470         sdp->sd_quota_bitmap = NULL;
1471 }
1472
1473 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1474 {
1475         if (error == 0 || error == -EROFS)
1476                 return;
1477         if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) {
1478                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1479                 sdp->sd_log_error = error;
1480                 wake_up(&sdp->sd_logd_waitq);
1481         }
1482 }
1483
1484 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1485                                int (*fxn)(struct super_block *sb, int type),
1486                                unsigned long t, unsigned long *timeo,
1487                                unsigned int *new_timeo)
1488 {
1489         if (t >= *timeo) {
1490                 int error = fxn(sdp->sd_vfs, 0);
1491                 quotad_error(sdp, msg, error);
1492                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1493         } else {
1494                 *timeo -= t;
1495         }
1496 }
1497
1498 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1499 {
1500         struct gfs2_inode *ip;
1501
1502         while(1) {
1503                 ip = NULL;
1504                 spin_lock(&sdp->sd_trunc_lock);
1505                 if (!list_empty(&sdp->sd_trunc_list)) {
1506                         ip = list_entry(sdp->sd_trunc_list.next,
1507                                         struct gfs2_inode, i_trunc_list);
1508                         list_del_init(&ip->i_trunc_list);
1509                 }
1510                 spin_unlock(&sdp->sd_trunc_lock);
1511                 if (ip == NULL)
1512                         return;
1513                 gfs2_glock_finish_truncate(ip);
1514         }
1515 }
1516
1517 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1518         if (!sdp->sd_statfs_force_sync) {
1519                 sdp->sd_statfs_force_sync = 1;
1520                 wake_up(&sdp->sd_quota_wait);
1521         }
1522 }
1523
1524
1525 /**
1526  * gfs2_quotad - Write cached quota changes into the quota file
1527  * @sdp: Pointer to GFS2 superblock
1528  *
1529  */
1530
1531 int gfs2_quotad(void *data)
1532 {
1533         struct gfs2_sbd *sdp = data;
1534         struct gfs2_tune *tune = &sdp->sd_tune;
1535         unsigned long statfs_timeo = 0;
1536         unsigned long quotad_timeo = 0;
1537         unsigned long t = 0;
1538         DEFINE_WAIT(wait);
1539         int empty;
1540
1541         while (!kthread_should_stop()) {
1542
1543                 /* Update the master statfs file */
1544                 if (sdp->sd_statfs_force_sync) {
1545                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1546                         quotad_error(sdp, "statfs", error);
1547                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1548                 }
1549                 else
1550                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1551                                            &statfs_timeo,
1552                                            &tune->gt_statfs_quantum);
1553
1554                 /* Update quota file */
1555                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1556                                    &quotad_timeo, &tune->gt_quota_quantum);
1557
1558                 /* Check for & recover partially truncated inodes */
1559                 quotad_check_trunc_list(sdp);
1560
1561                 try_to_freeze();
1562
1563                 t = min(quotad_timeo, statfs_timeo);
1564
1565                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1566                 spin_lock(&sdp->sd_trunc_lock);
1567                 empty = list_empty(&sdp->sd_trunc_list);
1568                 spin_unlock(&sdp->sd_trunc_lock);
1569                 if (empty && !sdp->sd_statfs_force_sync)
1570                         t -= schedule_timeout(t);
1571                 else
1572                         t = 0;
1573                 finish_wait(&sdp->sd_quota_wait, &wait);
1574         }
1575
1576         return 0;
1577 }
1578
1579 static int gfs2_quota_get_state(struct super_block *sb, struct qc_state *state)
1580 {
1581         struct gfs2_sbd *sdp = sb->s_fs_info;
1582
1583         memset(state, 0, sizeof(*state));
1584
1585         switch (sdp->sd_args.ar_quota) {
1586         case GFS2_QUOTA_ON:
1587                 state->s_state[USRQUOTA].flags |= QCI_LIMITS_ENFORCED;
1588                 state->s_state[GRPQUOTA].flags |= QCI_LIMITS_ENFORCED;
1589                 /*FALLTHRU*/
1590         case GFS2_QUOTA_ACCOUNT:
1591                 state->s_state[USRQUOTA].flags |= QCI_ACCT_ENABLED |
1592                                                   QCI_SYSFILE;
1593                 state->s_state[GRPQUOTA].flags |= QCI_ACCT_ENABLED |
1594                                                   QCI_SYSFILE;
1595                 break;
1596         case GFS2_QUOTA_OFF:
1597                 break;
1598         }
1599         if (sdp->sd_quota_inode) {
1600                 state->s_state[USRQUOTA].ino =
1601                                         GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1602                 state->s_state[USRQUOTA].blocks = sdp->sd_quota_inode->i_blocks;
1603         }
1604         state->s_state[USRQUOTA].nextents = 1;  /* unsupported */
1605         state->s_state[GRPQUOTA] = state->s_state[USRQUOTA];
1606         state->s_incoredqs = list_lru_count(&gfs2_qd_lru);
1607         return 0;
1608 }
1609
1610 static int gfs2_get_dqblk(struct super_block *sb, struct kqid qid,
1611                           struct qc_dqblk *fdq)
1612 {
1613         struct gfs2_sbd *sdp = sb->s_fs_info;
1614         struct gfs2_quota_lvb *qlvb;
1615         struct gfs2_quota_data *qd;
1616         struct gfs2_holder q_gh;
1617         int error;
1618
1619         memset(fdq, 0, sizeof(*fdq));
1620
1621         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1622                 return -ESRCH; /* Crazy XFS error code */
1623
1624         if ((qid.type != USRQUOTA) &&
1625             (qid.type != GRPQUOTA))
1626                 return -EINVAL;
1627
1628         error = qd_get(sdp, qid, &qd);
1629         if (error)
1630                 return error;
1631         error = do_glock(qd, FORCE, &q_gh);
1632         if (error)
1633                 goto out;
1634
1635         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1636         fdq->d_spc_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_sb.sb_bsize_shift;
1637         fdq->d_spc_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_sb.sb_bsize_shift;
1638         fdq->d_space = be64_to_cpu(qlvb->qb_value) << sdp->sd_sb.sb_bsize_shift;
1639
1640         gfs2_glock_dq_uninit(&q_gh);
1641 out:
1642         qd_put(qd);
1643         return error;
1644 }
1645
1646 /* GFS2 only supports a subset of the XFS fields */
1647 #define GFS2_FIELDMASK (QC_SPC_SOFT|QC_SPC_HARD|QC_SPACE)
1648
1649 static int gfs2_set_dqblk(struct super_block *sb, struct kqid qid,
1650                           struct qc_dqblk *fdq)
1651 {
1652         struct gfs2_sbd *sdp = sb->s_fs_info;
1653         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1654         struct gfs2_quota_data *qd;
1655         struct gfs2_holder q_gh, i_gh;
1656         unsigned int data_blocks, ind_blocks;
1657         unsigned int blocks = 0;
1658         int alloc_required;
1659         loff_t offset;
1660         int error;
1661
1662         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1663                 return -ESRCH; /* Crazy XFS error code */
1664
1665         if ((qid.type != USRQUOTA) &&
1666             (qid.type != GRPQUOTA))
1667                 return -EINVAL;
1668
1669         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1670                 return -EINVAL;
1671
1672         error = qd_get(sdp, qid, &qd);
1673         if (error)
1674                 return error;
1675
1676         error = gfs2_rsqa_alloc(ip);
1677         if (error)
1678                 goto out_put;
1679
1680         inode_lock(&ip->i_inode);
1681         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1682         if (error)
1683                 goto out_unlockput;
1684         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1685         if (error)
1686                 goto out_q;
1687
1688         /* Check for existing entry, if none then alloc new blocks */
1689         error = update_qd(sdp, qd);
1690         if (error)
1691                 goto out_i;
1692
1693         /* If nothing has changed, this is a no-op */
1694         if ((fdq->d_fieldmask & QC_SPC_SOFT) &&
1695             ((fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1696                 fdq->d_fieldmask ^= QC_SPC_SOFT;
1697
1698         if ((fdq->d_fieldmask & QC_SPC_HARD) &&
1699             ((fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1700                 fdq->d_fieldmask ^= QC_SPC_HARD;
1701
1702         if ((fdq->d_fieldmask & QC_SPACE) &&
1703             ((fdq->d_space >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1704                 fdq->d_fieldmask ^= QC_SPACE;
1705
1706         if (fdq->d_fieldmask == 0)
1707                 goto out_i;
1708
1709         offset = qd2offset(qd);
1710         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1711         if (gfs2_is_stuffed(ip))
1712                 alloc_required = 1;
1713         if (alloc_required) {
1714                 struct gfs2_alloc_parms ap = { .aflags = 0, };
1715                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1716                                        &data_blocks, &ind_blocks);
1717                 blocks = 1 + data_blocks + ind_blocks;
1718                 ap.target = blocks;
1719                 error = gfs2_inplace_reserve(ip, &ap);
1720                 if (error)
1721                         goto out_i;
1722                 blocks += gfs2_rg_blocks(ip, blocks);
1723         }
1724
1725         /* Some quotas span block boundaries and can update two blocks,
1726            adding an extra block to the transaction to handle such quotas */
1727         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1728         if (error)
1729                 goto out_release;
1730
1731         /* Apply changes */
1732         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1733         if (!error)
1734                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
1735
1736         gfs2_trans_end(sdp);
1737 out_release:
1738         if (alloc_required)
1739                 gfs2_inplace_release(ip);
1740 out_i:
1741         gfs2_glock_dq_uninit(&i_gh);
1742 out_q:
1743         gfs2_glock_dq_uninit(&q_gh);
1744 out_unlockput:
1745         inode_unlock(&ip->i_inode);
1746 out_put:
1747         qd_put(qd);
1748         return error;
1749 }
1750
1751 const struct quotactl_ops gfs2_quotactl_ops = {
1752         .quota_sync     = gfs2_quota_sync,
1753         .get_state      = gfs2_quota_get_state,
1754         .get_dqblk      = gfs2_get_dqblk,
1755         .set_dqblk      = gfs2_set_dqblk,
1756 };
1757
1758 void __init gfs2_quota_hash_init(void)
1759 {
1760         unsigned i;
1761
1762         for(i = 0; i < GFS2_QD_HASH_SIZE; i++)
1763                 INIT_HLIST_BL_HEAD(&qd_hash_table[i]);
1764 }