fs/gfs2/quota.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   4  * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
   5  */
   6
   7 /*
   8  * Quota change tags are associated with each transaction that allocates or
   9  * deallocates space.  Those changes are accumulated locally to each node (in a
  10  * per-node file) and then are periodically synced to the quota file.  This
  11  * avoids the bottleneck of constantly touching the quota file, but introduces
  12  * fuzziness in the current usage value of IDs that are being used on different
  13  * nodes in the cluster simultaneously.  So, it is possible for a user on
  14  * multiple nodes to overrun their quota, but that overrun is controlable.
  15  * Since quota tags are part of transactions, there is no need for a quota check
  16  * program to be run on node crashes or anything like that.
  17  *
  18  * There are couple of knobs that let the administrator manage the quota
  19  * fuzziness.  "quota_quantum" sets the maximum time a quota change can be
  20  * sitting on one node before being synced to the quota file.  (The default is
  21  * 60 seconds.)  Another knob, "quota_scale" controls how quickly the frequency
  22  * of quota file syncs increases as the user moves closer to their limit.  The
  23  * more frequent the syncs, the more accurate the quota enforcement, but that
  24  * means that there is more contention between the nodes for the quota file.
  25  * The default value is one.  This sets the maximum theoretical quota overrun
  26  * (with infinite node with infinite bandwidth) to twice the user's limit.  (In
  27  * practice, the maximum overrun you see should be much less.)  A "quota_scale"
  28  * number greater than one makes quota syncs more frequent and reduces the
  29  * maximum overrun.  Numbers less than one (but greater than zero) make quota
  30  * syncs less frequent.
  31  *
  32  * GFS quotas also use per-ID Lock Value Blocks (LVBs) to cache the contents of
  33  * the quota file, so it is not being constantly read.
  34  */
  35
  36 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  37
  38 #include <linux/sched.h>
  39 #include <linux/slab.h>
  40 #include <linux/mm.h>
  41 #include <linux/spinlock.h>
  42 #include <linux/completion.h>
  43 #include <linux/buffer_head.h>
  44 #include <linux/sort.h>
  45 #include <linux/fs.h>
  46 #include <linux/bio.h>
  47 #include <linux/gfs2_ondisk.h>
  48 #include <linux/kthread.h>
  49 #include <linux/freezer.h>
  50 #include <linux/quota.h>
  51 #include <linux/dqblk_xfs.h>
  52 #include <linux/lockref.h>
  53 #include <linux/list_lru.h>
  54 #include <linux/rcupdate.h>
  55 #include <linux/rculist_bl.h>
  56 #include <linux/bit_spinlock.h>
  57 #include <linux/jhash.h>
  58 #include <linux/vmalloc.h>
  59
  60 #include "gfs2.h"
  61 #include "incore.h"
  62 #include "bmap.h"
  63 #include "glock.h"
  64 #include "glops.h"
  65 #include "log.h"
  66 #include "meta_io.h"
  67 #include "quota.h"
  68 #include "rgrp.h"
  69 #include "super.h"
  70 #include "trans.h"
  71 #include "inode.h"
  72 #include "util.h"
  73
  74 #define GFS2_QD_HASH_SHIFT      12
  75 #define GFS2_QD_HASH_SIZE       BIT(GFS2_QD_HASH_SHIFT)
  76 #define GFS2_QD_HASH_MASK       (GFS2_QD_HASH_SIZE - 1)
  77
  78 /* Lock order: qd_lock -> bucket lock -> qd->lockref.lock -> lru lock */
  79 /*                     -> sd_bitmap_lock                              */
  80 static DEFINE_SPINLOCK(qd_lock);
  81 struct list_lru gfs2_qd_lru;
  82
  83 static struct hlist_bl_head qd_hash_table[GFS2_QD_HASH_SIZE];
  84
  85 static unsigned int gfs2_qd_hash(const struct gfs2_sbd *sdp,
  86                                  const struct kqid qid)
  87 {
  88         unsigned int h;
  89
  90         h = jhash(&sdp, sizeof(struct gfs2_sbd *), 0);
  91         h = jhash(&qid, sizeof(struct kqid), h);
  92
  93         return h & GFS2_QD_HASH_MASK;
  94 }
  95
  96 static inline void spin_lock_bucket(unsigned int hash)
  97 {
  98         hlist_bl_lock(&qd_hash_table[hash]);
  99 }
 100
 101 static inline void spin_unlock_bucket(unsigned int hash)
 102 {
 103         hlist_bl_unlock(&qd_hash_table[hash]);
 104 }
 105
 106 static void gfs2_qd_dealloc(struct rcu_head *rcu)
 107 {
 108         struct gfs2_quota_data *qd = container_of(rcu, struct gfs2_quota_data, qd_rcu);
 109         kmem_cache_free(gfs2_quotad_cachep, qd);
 110 }
 111
 112 static void gfs2_qd_dispose(struct list_head *list)
 113 {
 114         struct gfs2_quota_data *qd;
 115         struct gfs2_sbd *sdp;
 116
 117         while (!list_empty(list)) {
 118                 qd = list_first_entry(list, struct gfs2_quota_data, qd_lru);
 119                 sdp = qd->qd_gl->gl_name.ln_sbd;
 120
 121                 list_del(&qd->qd_lru);
 122
 123                 /* Free from the filesystem-specific list */
 124                 spin_lock(&qd_lock);
 125                 list_del(&qd->qd_list);
 126                 spin_unlock(&qd_lock);
 127
 128                 spin_lock_bucket(qd->qd_hash);
 129                 hlist_bl_del_rcu(&qd->qd_hlist);
 130                 spin_unlock_bucket(qd->qd_hash);
 131
 132                 gfs2_assert_warn(sdp, !qd->qd_change);
 133                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
 134                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
 135
 136                 gfs2_glock_put(qd->qd_gl);
 137                 atomic_dec(&sdp->sd_quota_count);
 138
 139                 /* Delete it from the common reclaim list */
 140                 call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
 141         }
 142 }
 143
 144
 145 static enum lru_status gfs2_qd_isolate(struct list_head *item,
 146                 struct list_lru_one *lru, spinlock_t *lru_lock, void *arg)
 147 {
 148         struct list_head *dispose = arg;
 149         struct gfs2_quota_data *qd = list_entry(item, struct gfs2_quota_data, qd_lru);
 150
 151         if (!spin_trylock(&qd->qd_lockref.lock))
 152                 return LRU_SKIP;
 153
 154         if (qd->qd_lockref.count == 0) {
 155                 lockref_mark_dead(&qd->qd_lockref);
 156                 list_lru_isolate_move(lru, &qd->qd_lru, dispose);
 157         }
 158
 159         spin_unlock(&qd->qd_lockref.lock);
 160         return LRU_REMOVED;
 161 }
 162
 163 static unsigned long gfs2_qd_shrink_scan(struct shrinker *shrink,
 164                                          struct shrink_control *sc)
 165 {
 166         LIST_HEAD(dispose);
 167         unsigned long freed;
 168
 169         if (!(sc->gfp_mask & __GFP_FS))
 170                 return SHRINK_STOP;
 171
 172         freed = list_lru_shrink_walk(&gfs2_qd_lru, sc,
 173                                      gfs2_qd_isolate, &dispose);
 174
 175         gfs2_qd_dispose(&dispose);
 176
 177         return freed;
 178 }
 179
 180 static unsigned long gfs2_qd_shrink_count(struct shrinker *shrink,
 181                                           struct shrink_control *sc)
 182 {
 183         return vfs_pressure_ratio(list_lru_shrink_count(&gfs2_qd_lru, sc));
 184 }
 185
 186 struct shrinker gfs2_qd_shrinker = {
 187         .count_objects = gfs2_qd_shrink_count,
 188         .scan_objects = gfs2_qd_shrink_scan,
 189         .seeks = DEFAULT_SEEKS,
 190         .flags = SHRINKER_NUMA_AWARE,
 191 };
 192
 193
 194 static u64 qd2index(struct gfs2_quota_data *qd)
 195 {
 196         struct kqid qid = qd->qd_id;
 197         return (2 * (u64)from_kqid(&init_user_ns, qid)) +
 198                 ((qid.type == USRQUOTA) ? 0 : 1);
 199 }
 200
 201 static u64 qd2offset(struct gfs2_quota_data *qd)
 202 {
 203         u64 offset;
 204
 205         offset = qd2index(qd);
 206         offset *= sizeof(struct gfs2_quota);
 207
 208         return offset;
 209 }
 210
 211 static struct gfs2_quota_data *qd_alloc(unsigned hash, struct gfs2_sbd *sdp, struct kqid qid)
 212 {
 213         struct gfs2_quota_data *qd;
 214         int error;
 215
 216         qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
 217         if (!qd)
 218                 return NULL;
 219
 220         qd->qd_sbd = sdp;
 221         qd->qd_lockref.count = 1;
 222         spin_lock_init(&qd->qd_lockref.lock);
 223         qd->qd_id = qid;
 224         qd->qd_slot = -1;
 225         INIT_LIST_HEAD(&qd->qd_lru);
 226         qd->qd_hash = hash;
 227
 228         error = gfs2_glock_get(sdp, qd2index(qd),
 229                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
 230         if (error)
 231                 goto fail;
 232
 233         return qd;
 234
 235 fail:
 236         kmem_cache_free(gfs2_quotad_cachep, qd);
 237         return NULL;
 238 }
 239
 240 static struct gfs2_quota_data *gfs2_qd_search_bucket(unsigned int hash,
 241                                                      const struct gfs2_sbd *sdp,
 242                                                      struct kqid qid)
 243 {
 244         struct gfs2_quota_data *qd;
 245         struct hlist_bl_node *h;
 246
 247         hlist_bl_for_each_entry_rcu(qd, h, &qd_hash_table[hash], qd_hlist) {
 248                 if (!qid_eq(qd->qd_id, qid))
 249                         continue;
 250                 if (qd->qd_sbd != sdp)
 251                         continue;
 252                 if (lockref_get_not_dead(&qd->qd_lockref)) {
 253                         list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
 254                         return qd;
 255                 }
 256         }
 257
 258         return NULL;
 259 }
 260
 261
 262 static int qd_get(struct gfs2_sbd *sdp, struct kqid qid,
 263                   struct gfs2_quota_data **qdp)
 264 {
 265         struct gfs2_quota_data *qd, *new_qd;
 266         unsigned int hash = gfs2_qd_hash(sdp, qid);
 267
 268         rcu_read_lock();
 269         *qdp = qd = gfs2_qd_search_bucket(hash, sdp, qid);
 270         rcu_read_unlock();
 271
 272         if (qd)
 273                 return 0;
 274
 275         new_qd = qd_alloc(hash, sdp, qid);
 276         if (!new_qd)
 277                 return -ENOMEM;
 278
 279         spin_lock(&qd_lock);
 280         spin_lock_bucket(hash);
 281         *qdp = qd = gfs2_qd_search_bucket(hash, sdp, qid);
 282         if (qd == NULL) {
 283                 *qdp = new_qd;
 284                 list_add(&new_qd->qd_list, &sdp->sd_quota_list);
 285                 hlist_bl_add_head_rcu(&new_qd->qd_hlist, &qd_hash_table[hash]);
 286                 atomic_inc(&sdp->sd_quota_count);
 287         }
 288         spin_unlock_bucket(hash);
 289         spin_unlock(&qd_lock);
 290
 291         if (qd) {
 292                 gfs2_glock_put(new_qd->qd_gl);
 293                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
 294         }
 295
 296         return 0;
 297 }
 298
 299
 300 static void qd_hold(struct gfs2_quota_data *qd)
 301 {
 302         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
 303         gfs2_assert(sdp, !__lockref_is_dead(&qd->qd_lockref));
 304         lockref_get(&qd->qd_lockref);
 305 }
 306
 307 static void qd_put(struct gfs2_quota_data *qd)
 308 {
 309         if (lockref_put_or_lock(&qd->qd_lockref))
 310                 return;
 311
 312         qd->qd_lockref.count = 0;
 313         list_lru_add(&gfs2_qd_lru, &qd->qd_lru);
 314         spin_unlock(&qd->qd_lockref.lock);
 315
 316 }
 317
 318 static int slot_get(struct gfs2_quota_data *qd)
 319 {
 320         struct gfs2_sbd *sdp = qd->qd_sbd;
 321         unsigned int bit;
 322         int error = 0;
 323
 324         spin_lock(&sdp->sd_bitmap_lock);
 325         if (qd->qd_slot_count != 0)
 326                 goto out;
 327
 328         error = -ENOSPC;
 329         bit = find_first_zero_bit(sdp->sd_quota_bitmap, sdp->sd_quota_slots);
 330         if (bit < sdp->sd_quota_slots) {
 331                 set_bit(bit, sdp->sd_quota_bitmap);
 332                 qd->qd_slot = bit;
 333                 error = 0;
 334 out:
 335                 qd->qd_slot_count++;
 336         }
 337         spin_unlock(&sdp->sd_bitmap_lock);
 338
 339         return error;
 340 }
 341
 342 static void slot_hold(struct gfs2_quota_data *qd)
 343 {
 344         struct gfs2_sbd *sdp = qd->qd_sbd;
 345
 346         spin_lock(&sdp->sd_bitmap_lock);
 347         gfs2_assert(sdp, qd->qd_slot_count);
 348         qd->qd_slot_count++;
 349         spin_unlock(&sdp->sd_bitmap_lock);
 350 }
 351
 352 static void slot_put(struct gfs2_quota_data *qd)
 353 {
 354         struct gfs2_sbd *sdp = qd->qd_sbd;
 355
 356         spin_lock(&sdp->sd_bitmap_lock);
 357         gfs2_assert(sdp, qd->qd_slot_count);
 358         if (!--qd->qd_slot_count) {
 359                 BUG_ON(!test_and_clear_bit(qd->qd_slot, sdp->sd_quota_bitmap));
 360                 qd->qd_slot = -1;
 361         }
 362         spin_unlock(&sdp->sd_bitmap_lock);
 363 }
 364
 365 static int bh_get(struct gfs2_quota_data *qd)
 366 {
 367         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
 368         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 369         unsigned int block, offset;
 370         struct buffer_head *bh;
 371         int error;
 372         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
 373
 374         mutex_lock(&sdp->sd_quota_mutex);
 375
 376         if (qd->qd_bh_count++) {
 377                 mutex_unlock(&sdp->sd_quota_mutex);
 378                 return 0;
 379         }
 380
 381         block = qd->qd_slot / sdp->sd_qc_per_block;
 382         offset = qd->qd_slot % sdp->sd_qc_per_block;
 383
 384         bh_map.b_size = BIT(ip->i_inode.i_blkbits);
 385         error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
 386         if (error)
 387                 goto fail;
 388         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, 0, &bh);
 389         if (error)
 390                 goto fail;
 391         error = -EIO;
 392         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
 393                 goto fail_brelse;
 394
 395         qd->qd_bh = bh;
 396         qd->qd_bh_qc = (struct gfs2_quota_change *)
 397                 (bh->b_data + sizeof(struct gfs2_meta_header) +
 398                  offset * sizeof(struct gfs2_quota_change));
 399
 400         mutex_unlock(&sdp->sd_quota_mutex);
 401
 402         return 0;
 403
 404 fail_brelse:
 405         brelse(bh);
 406 fail:
 407         qd->qd_bh_count--;
 408         mutex_unlock(&sdp->sd_quota_mutex);
 409         return error;
 410 }
 411
 412 static void bh_put(struct gfs2_quota_data *qd)
 413 {
 414         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
 415
 416         mutex_lock(&sdp->sd_quota_mutex);
 417         gfs2_assert(sdp, qd->qd_bh_count);
 418         if (!--qd->qd_bh_count) {
 419                 brelse(qd->qd_bh);
 420                 qd->qd_bh = NULL;
 421                 qd->qd_bh_qc = NULL;
 422         }
 423         mutex_unlock(&sdp->sd_quota_mutex);
 424 }
 425
 426 static int qd_check_sync(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd,
 427                          u64 *sync_gen)
 428 {
 429         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 430             !test_bit(QDF_CHANGE, &qd->qd_flags) ||
 431             (sync_gen && (qd->qd_sync_gen >= *sync_gen)))
 432                 return 0;
 433
 434         if (!lockref_get_not_dead(&qd->qd_lockref))
 435                 return 0;
 436
 437         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 438         set_bit(QDF_LOCKED, &qd->qd_flags);
 439         qd->qd_change_sync = qd->qd_change;
 440         slot_hold(qd);
 441         return 1;
 442 }
 443
 444 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
 445 {
 446         struct gfs2_quota_data *qd = NULL;
 447         int error;
 448         int found = 0;
 449
 450         *qdp = NULL;
 451
 452         if (sb_rdonly(sdp->sd_vfs))
 453                 return 0;
 454
 455         spin_lock(&qd_lock);
 456
 457         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 458                 found = qd_check_sync(sdp, qd, &sdp->sd_quota_sync_gen);
 459                 if (found)
 460                         break;
 461         }
 462
 463         if (!found)
 464                 qd = NULL;
 465
 466         spin_unlock(&qd_lock);
 467
 468         if (qd) {
 469                 gfs2_assert_warn(sdp, qd->qd_change_sync);
 470                 error = bh_get(qd);
 471                 if (error) {
 472                         clear_bit(QDF_LOCKED, &qd->qd_flags);
 473                         slot_put(qd);
 474                         qd_put(qd);
 475                         return error;
 476                 }
 477         }
 478
 479         *qdp = qd;
 480
 481         return 0;
 482 }
 483
 484 static void qd_unlock(struct gfs2_quota_data *qd)
 485 {
 486         gfs2_assert_warn(qd->qd_gl->gl_name.ln_sbd,
 487                          test_bit(QDF_LOCKED, &qd->qd_flags));
 488         clear_bit(QDF_LOCKED, &qd->qd_flags);
 489         bh_put(qd);
 490         slot_put(qd);
 491         qd_put(qd);
 492 }
 493
 494 static int qdsb_get(struct gfs2_sbd *sdp, struct kqid qid,
 495                     struct gfs2_quota_data **qdp)
 496 {
 497         int error;
 498
 499         error = qd_get(sdp, qid, qdp);
 500         if (error)
 501                 return error;
 502
 503         error = slot_get(*qdp);
 504         if (error)
 505                 goto fail;
 506
 507         error = bh_get(*qdp);
 508         if (error)
 509                 goto fail_slot;
 510
 511         return 0;
 512
 513 fail_slot:
 514         slot_put(*qdp);
 515 fail:
 516         qd_put(*qdp);
 517         return error;
 518 }
 519
 520 static void qdsb_put(struct gfs2_quota_data *qd)
 521 {
 522         bh_put(qd);
 523         slot_put(qd);
 524         qd_put(qd);
 525 }
 526
 527 /**
 528  * gfs2_qa_get - make sure we have a quota allocations data structure,
 529  *               if necessary
 530  * @ip: the inode for this reservation
 531  */
 532 int gfs2_qa_get(struct gfs2_inode *ip)
 533 {
 534         int error = 0;
 535         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 536
 537         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 538                 return 0;
 539
 540         down_write(&ip->i_rw_mutex);
 541         if (ip->i_qadata == NULL) {
 542                 ip->i_qadata = kmem_cache_zalloc(gfs2_qadata_cachep, GFP_NOFS);
 543                 if (!ip->i_qadata) {
 544                         error = -ENOMEM;
 545                         goto out;
 546                 }
 547         }
 548         ip->i_qadata->qa_ref++;
 549 out:
 550         up_write(&ip->i_rw_mutex);
 551         return error;
 552 }
 553
 554 void gfs2_qa_put(struct gfs2_inode *ip)
 555 {
 556         down_write(&ip->i_rw_mutex);
 557         if (ip->i_qadata && --ip->i_qadata->qa_ref == 0) {
 558                 kmem_cache_free(gfs2_qadata_cachep, ip->i_qadata);
 559                 ip->i_qadata = NULL;
 560         }
 561         up_write(&ip->i_rw_mutex);
 562 }
 563
 564 int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
 565 {
 566         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 567         struct gfs2_quota_data **qd;
 568         int error;
 569
 570         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 571                 return 0;
 572
 573         error = gfs2_qa_get(ip);
 574         if (error)
 575                 return error;
 576
 577         qd = ip->i_qadata->qa_qd;
 578
 579         if (gfs2_assert_warn(sdp, !ip->i_qadata->qa_qd_num) ||
 580             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags))) {
 581                 error = -EIO;
 582                 goto out;
 583         }
 584
 585         error = qdsb_get(sdp, make_kqid_uid(ip->i_inode.i_uid), qd);
 586         if (error)
 587                 goto out_unhold;
 588         ip->i_qadata->qa_qd_num++;
 589         qd++;
 590
 591         error = qdsb_get(sdp, make_kqid_gid(ip->i_inode.i_gid), qd);
 592         if (error)
 593                 goto out_unhold;
 594         ip->i_qadata->qa_qd_num++;
 595         qd++;
 596
 597         if (!uid_eq(uid, NO_UID_QUOTA_CHANGE) &&
 598             !uid_eq(uid, ip->i_inode.i_uid)) {
 599                 error = qdsb_get(sdp, make_kqid_uid(uid), qd);
 600                 if (error)
 601                         goto out_unhold;
 602                 ip->i_qadata->qa_qd_num++;
 603                 qd++;
 604         }
 605
 606         if (!gid_eq(gid, NO_GID_QUOTA_CHANGE) &&
 607             !gid_eq(gid, ip->i_inode.i_gid)) {
 608                 error = qdsb_get(sdp, make_kqid_gid(gid), qd);
 609                 if (error)
 610                         goto out_unhold;
 611                 ip->i_qadata->qa_qd_num++;
 612                 qd++;
 613         }
 614
 615 out_unhold:
 616         if (error)
 617                 gfs2_quota_unhold(ip);
 618 out:
 619         return error;
 620 }
 621
 622 void gfs2_quota_unhold(struct gfs2_inode *ip)
 623 {
 624         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 625         u32 x;
 626
 627         if (ip->i_qadata == NULL)
 628                 return;
 629
 630         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 631
 632         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
 633                 qdsb_put(ip->i_qadata->qa_qd[x]);
 634                 ip->i_qadata->qa_qd[x] = NULL;
 635         }
 636         ip->i_qadata->qa_qd_num = 0;
 637         gfs2_qa_put(ip);
 638 }
 639
 640 static int sort_qd(const void *a, const void *b)
 641 {
 642         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
 643         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
 644
 645         if (qid_lt(qd_a->qd_id, qd_b->qd_id))
 646                 return -1;
 647         if (qid_lt(qd_b->qd_id, qd_a->qd_id))
 648                 return 1;
 649         return 0;
 650 }
 651
 652 static void do_qc(struct gfs2_quota_data *qd, s64 change)
 653 {
 654         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
 655         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 656         struct gfs2_quota_change *qc = qd->qd_bh_qc;
 657         s64 x;
 658
 659         mutex_lock(&sdp->sd_quota_mutex);
 660         gfs2_trans_add_meta(ip->i_gl, qd->qd_bh);
 661
 662         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
 663                 qc->qc_change = 0;
 664                 qc->qc_flags = 0;
 665                 if (qd->qd_id.type == USRQUOTA)
 666                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
 667                 qc->qc_id = cpu_to_be32(from_kqid(&init_user_ns, qd->qd_id));
 668         }
 669
 670         x = be64_to_cpu(qc->qc_change) + change;
 671         qc->qc_change = cpu_to_be64(x);
 672
 673         spin_lock(&qd_lock);
 674         qd->qd_change = x;
 675         spin_unlock(&qd_lock);
 676
 677         if (!x) {
 678                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
 679                 clear_bit(QDF_CHANGE, &qd->qd_flags);
 680                 qc->qc_flags = 0;
 681                 qc->qc_id = 0;
 682                 slot_put(qd);
 683                 qd_put(qd);
 684         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
 685                 qd_hold(qd);
 686                 slot_hold(qd);
 687         }
 688
 689         if (change < 0) /* Reset quiet flag if we freed some blocks */
 690                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
 691         mutex_unlock(&sdp->sd_quota_mutex);
 692 }
 693
 694 static int gfs2_write_buf_to_page(struct gfs2_inode *ip, unsigned long index,
 695                                   unsigned off, void *buf, unsigned bytes)
 696 {
 697         struct inode *inode = &ip->i_inode;
 698         struct gfs2_sbd *sdp = GFS2_SB(inode);
 699         struct address_space *mapping = inode->i_mapping;
 700         struct page *page;
 701         struct buffer_head *bh;
 702         void *kaddr;
 703         u64 blk;
 704         unsigned bsize = sdp->sd_sb.sb_bsize, bnum = 0, boff = 0;
 705         unsigned to_write = bytes, pg_off = off;
 706         int done = 0;
 707
 708         blk = index << (PAGE_SHIFT - sdp->sd_sb.sb_bsize_shift);
 709         boff = off % bsize;
 710
 711         page = find_or_create_page(mapping, index, GFP_NOFS);
 712         if (!page)
 713                 return -ENOMEM;
 714         if (!page_has_buffers(page))
 715                 create_empty_buffers(page, bsize, 0);
 716
 717         bh = page_buffers(page);
 718         while (!done) {
 719                 /* Find the beginning block within the page */
 720                 if (pg_off >= ((bnum * bsize) + bsize)) {
 721                         bh = bh->b_this_page;
 722                         bnum++;
 723                         blk++;
 724                         continue;
 725                 }
 726                 if (!buffer_mapped(bh)) {
 727                         gfs2_block_map(inode, blk, bh, 1);
 728                         if (!buffer_mapped(bh))
 729                                 goto unlock_out;
 730                         /* If it's a newly allocated disk block, zero it */
 731                         if (buffer_new(bh))
 732                                 zero_user(page, bnum * bsize, bh->b_size);
 733                 }
 734                 if (PageUptodate(page))
 735                         set_buffer_uptodate(bh);
 736                 if (!buffer_uptodate(bh)) {
 737                         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &bh);
 738                         wait_on_buffer(bh);
 739                         if (!buffer_uptodate(bh))
 740                                 goto unlock_out;
 741                 }
 742                 if (gfs2_is_jdata(ip))
 743                         gfs2_trans_add_data(ip->i_gl, bh);
 744                 else
 745                         gfs2_ordered_add_inode(ip);
 746
 747                 /* If we need to write to the next block as well */
 748                 if (to_write > (bsize - boff)) {
 749                         pg_off += (bsize - boff);
 750                         to_write -= (bsize - boff);
 751                         boff = pg_off % bsize;
 752                         continue;
 753                 }
 754                 done = 1;
 755         }
 756
 757         /* Write to the page, now that we have setup the buffer(s) */
 758         kaddr = kmap_atomic(page);
 759         memcpy(kaddr + off, buf, bytes);
 760         flush_dcache_page(page);
 761         kunmap_atomic(kaddr);
 762         unlock_page(page);
 763         put_page(page);
 764
 765         return 0;
 766
 767 unlock_out:
 768         unlock_page(page);
 769         put_page(page);
 770         return -EIO;
 771 }
 772
 773 static int gfs2_write_disk_quota(struct gfs2_inode *ip, struct gfs2_quota *qp,
 774                                  loff_t loc)
 775 {
 776         unsigned long pg_beg;
 777         unsigned pg_off, nbytes, overflow = 0;
 778         int pg_oflow = 0, error;
 779         void *ptr;
 780
 781         nbytes = sizeof(struct gfs2_quota);
 782
 783         pg_beg = loc >> PAGE_SHIFT;
 784         pg_off = offset_in_page(loc);
 785
 786         /* If the quota straddles a page boundary, split the write in two */
 787         if ((pg_off + nbytes) > PAGE_SIZE) {
 788                 pg_oflow = 1;
 789                 overflow = (pg_off + nbytes) - PAGE_SIZE;
 790         }
 791
 792         ptr = qp;
 793         error = gfs2_write_buf_to_page(ip, pg_beg, pg_off, ptr,
 794                                        nbytes - overflow);
 795         /* If there's an overflow, write the remaining bytes to the next page */
 796         if (!error && pg_oflow)
 797                 error = gfs2_write_buf_to_page(ip, pg_beg + 1, 0,
 798                                                ptr + nbytes - overflow,
 799                                                overflow);
 800         return error;
 801 }
 802
 803 /**
 804  * gfs2_adjust_quota - adjust record of current block usage
 805  * @ip: The quota inode
 806  * @loc: Offset of the entry in the quota file
 807  * @change: The amount of usage change to record
 808  * @qd: The quota data
 809  * @fdq: The updated limits to record
 810  *
 811  * This function was mostly borrowed from gfs2_block_truncate_page which was
 812  * in turn mostly borrowed from ext3
 813  *
 814  * Returns: 0 or -ve on error
 815  */
 816
 817 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 818                              s64 change, struct gfs2_quota_data *qd,
 819                              struct qc_dqblk *fdq)
 820 {
 821         struct inode *inode = &ip->i_inode;
 822         struct gfs2_sbd *sdp = GFS2_SB(inode);
 823         struct gfs2_quota q;
 824         int err;
 825         u64 size;
 826
 827         if (gfs2_is_stuffed(ip)) {
 828                 err = gfs2_unstuff_dinode(ip, NULL);
 829                 if (err)
 830                         return err;
 831         }
 832
 833         memset(&q, 0, sizeof(struct gfs2_quota));
 834         err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
 835         if (err < 0)
 836                 return err;
 837
 838         loc -= sizeof(q); /* gfs2_internal_read would've advanced the loc ptr */
 839         err = -EIO;
 840         be64_add_cpu(&q.qu_value, change);
 841         if (((s64)be64_to_cpu(q.qu_value)) < 0)
 842                 q.qu_value = 0; /* Never go negative on quota usage */
 843         qd->qd_qb.qb_value = q.qu_value;
 844         if (fdq) {
 845                 if (fdq->d_fieldmask & QC_SPC_SOFT) {
 846                         q.qu_warn = cpu_to_be64(fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift);
 847                         qd->qd_qb.qb_warn = q.qu_warn;
 848                 }
 849                 if (fdq->d_fieldmask & QC_SPC_HARD) {
 850                         q.qu_limit = cpu_to_be64(fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift);
 851                         qd->qd_qb.qb_limit = q.qu_limit;
 852                 }
 853                 if (fdq->d_fieldmask & QC_SPACE) {
 854                         q.qu_value = cpu_to_be64(fdq->d_space >> sdp->sd_sb.sb_bsize_shift);
 855                         qd->qd_qb.qb_value = q.qu_value;
 856                 }
 857         }
 858
 859         err = gfs2_write_disk_quota(ip, &q, loc);
 860         if (!err) {
 861                 size = loc + sizeof(struct gfs2_quota);
 862                 if (size > inode->i_size)
 863                         i_size_write(inode, size);
 864                 inode->i_mtime = inode->i_atime = current_time(inode);
 865                 mark_inode_dirty(inode);
 866                 set_bit(QDF_REFRESH, &qd->qd_flags);
 867         }
 868
 869         return err;
 870 }
 871
 872 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 873 {
 874         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_name.ln_sbd;
 875         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 876         struct gfs2_alloc_parms ap = { .aflags = 0, };
 877         unsigned int data_blocks, ind_blocks;
 878         struct gfs2_holder *ghs, i_gh;
 879         unsigned int qx, x;
 880         struct gfs2_quota_data *qd;
 881         unsigned reserved;
 882         loff_t offset;
 883         unsigned int nalloc = 0, blocks;
 884         int error;
 885
 886         error = gfs2_qa_get(ip);
 887         if (error)
 888                 return error;
 889
 890         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 891                               &data_blocks, &ind_blocks);
 892
 893         ghs = kmalloc_array(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
 894         if (!ghs) {
 895                 error = -ENOMEM;
 896                 goto out;
 897         }
 898
 899         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 900         inode_lock(&ip->i_inode);
 901         for (qx = 0; qx < num_qd; qx++) {
 902                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
 903                                            GL_NOCACHE, &ghs[qx]);
 904                 if (error)
 905                         goto out_dq;
 906         }
 907
 908         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 909         if (error)
 910                 goto out_dq;
 911
 912         for (x = 0; x < num_qd; x++) {
 913                 offset = qd2offset(qda[x]);
 914                 if (gfs2_write_alloc_required(ip, offset,
 915                                               sizeof(struct gfs2_quota)))
 916                         nalloc++;
 917         }
 918
 919         /*
 920          * 1 blk for unstuffing inode if stuffed. We add this extra
 921          * block to the reservation unconditionally. If the inode
 922          * doesn't need unstuffing, the block will be released to the
 923          * rgrp since it won't be allocated during the transaction
 924          */
 925         /* +3 in the end for unstuffing block, inode size update block
 926          * and another block in case quota straddles page boundary and
 927          * two blocks need to be updated instead of 1 */
 928         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
 929
 930         reserved = 1 + (nalloc * (data_blocks + ind_blocks));
 931         ap.target = reserved;
 932         error = gfs2_inplace_reserve(ip, &ap);
 933         if (error)
 934                 goto out_alloc;
 935
 936         if (nalloc)
 937                 blocks += gfs2_rg_blocks(ip, reserved) + nalloc * ind_blocks + RES_STATFS;
 938
 939         error = gfs2_trans_begin(sdp, blocks, 0);
 940         if (error)
 941                 goto out_ipres;
 942
 943         for (x = 0; x < num_qd; x++) {
 944                 qd = qda[x];
 945                 offset = qd2offset(qd);
 946                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
 947                 if (error)
 948                         goto out_end_trans;
 949
 950                 do_qc(qd, -qd->qd_change_sync);
 951                 set_bit(QDF_REFRESH, &qd->qd_flags);
 952         }
 953
 954         error = 0;
 955
 956 out_end_trans:
 957         gfs2_trans_end(sdp);
 958 out_ipres:
 959         gfs2_inplace_release(ip);
 960 out_alloc:
 961         gfs2_glock_dq_uninit(&i_gh);
 962 out_dq:
 963         while (qx--)
 964                 gfs2_glock_dq_uninit(&ghs[qx]);
 965         inode_unlock(&ip->i_inode);
 966         kfree(ghs);
 967         gfs2_log_flush(ip->i_gl->gl_name.ln_sbd, ip->i_gl,
 968                        GFS2_LOG_HEAD_FLUSH_NORMAL | GFS2_LFC_DO_SYNC);
 969 out:
 970         gfs2_qa_put(ip);
 971         return error;
 972 }
 973
 974 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
 975 {
 976         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 977         struct gfs2_quota q;
 978         struct gfs2_quota_lvb *qlvb;
 979         loff_t pos;
 980         int error;
 981
 982         memset(&q, 0, sizeof(struct gfs2_quota));
 983         pos = qd2offset(qd);
 984         error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
 985         if (error < 0)
 986                 return error;
 987
 988         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
 989         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
 990         qlvb->__pad = 0;
 991         qlvb->qb_limit = q.qu_limit;
 992         qlvb->qb_warn = q.qu_warn;
 993         qlvb->qb_value = q.qu_value;
 994         qd->qd_qb = *qlvb;
 995
 996         return 0;
 997 }
 998
 999 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
1000                     struct gfs2_holder *q_gh)
1001 {
1002         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1003         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1004         struct gfs2_holder i_gh;
1005         int error;
1006
1007 restart:
1008         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
1009         if (error)
1010                 return error;
1011
1012         if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
1013                 force_refresh = FORCE;
1014
1015         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1016
1017         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
1018                 gfs2_glock_dq_uninit(q_gh);
1019                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
1020                                            GL_NOCACHE, q_gh);
1021                 if (error)
1022                         return error;
1023
1024                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
1025                 if (error)
1026                         goto fail;
1027
1028                 error = update_qd(sdp, qd);
1029                 if (error)
1030                         goto fail_gunlock;
1031
1032                 gfs2_glock_dq_uninit(&i_gh);
1033                 gfs2_glock_dq_uninit(q_gh);
1034                 force_refresh = 0;
1035                 goto restart;
1036         }
1037
1038         return 0;
1039
1040 fail_gunlock:
1041         gfs2_glock_dq_uninit(&i_gh);
1042 fail:
1043         gfs2_glock_dq_uninit(q_gh);
1044         return error;
1045 }
1046
1047 int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
1048 {
1049         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1050         struct gfs2_quota_data *qd;
1051         u32 x;
1052         int error = 0;
1053
1054         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1055                 return 0;
1056
1057         error = gfs2_quota_hold(ip, uid, gid);
1058         if (error)
1059                 return error;
1060
1061         sort(ip->i_qadata->qa_qd, ip->i_qadata->qa_qd_num,
1062              sizeof(struct gfs2_quota_data *), sort_qd, NULL);
1063
1064         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1065                 qd = ip->i_qadata->qa_qd[x];
1066                 error = do_glock(qd, NO_FORCE, &ip->i_qadata->qa_qd_ghs[x]);
1067                 if (error)
1068                         break;
1069         }
1070
1071         if (!error)
1072                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
1073         else {
1074                 while (x--)
1075                         gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
1076                 gfs2_quota_unhold(ip);
1077         }
1078
1079         return error;
1080 }
1081
1082 static int need_sync(struct gfs2_quota_data *qd)
1083 {
1084         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1085         struct gfs2_tune *gt = &sdp->sd_tune;
1086         s64 value;
1087         unsigned int num, den;
1088         int do_sync = 1;
1089
1090         if (!qd->qd_qb.qb_limit)
1091                 return 0;
1092
1093         spin_lock(&qd_lock);
1094         value = qd->qd_change;
1095         spin_unlock(&qd_lock);
1096
1097         spin_lock(&gt->gt_spin);
1098         num = gt->gt_quota_scale_num;
1099         den = gt->gt_quota_scale_den;
1100         spin_unlock(&gt->gt_spin);
1101
1102         if (value < 0)
1103                 do_sync = 0;
1104         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
1105                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1106                 do_sync = 0;
1107         else {
1108                 value *= gfs2_jindex_size(sdp) * num;
1109                 value = div_s64(value, den);
1110                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
1111                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1112                         do_sync = 0;
1113         }
1114
1115         return do_sync;
1116 }
1117
1118 void gfs2_quota_unlock(struct gfs2_inode *ip)
1119 {
1120         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1121         struct gfs2_quota_data *qda[4];
1122         unsigned int count = 0;
1123         u32 x;
1124         int found;
1125
1126         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1127                 return;
1128
1129         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1130                 struct gfs2_quota_data *qd;
1131                 int sync;
1132
1133                 qd = ip->i_qadata->qa_qd[x];
1134                 sync = need_sync(qd);
1135
1136                 gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
1137                 if (!sync)
1138                         continue;
1139
1140                 spin_lock(&qd_lock);
1141                 found = qd_check_sync(sdp, qd, NULL);
1142                 spin_unlock(&qd_lock);
1143
1144                 if (!found)
1145                         continue;
1146
1147                 gfs2_assert_warn(sdp, qd->qd_change_sync);
1148                 if (bh_get(qd)) {
1149                         clear_bit(QDF_LOCKED, &qd->qd_flags);
1150                         slot_put(qd);
1151                         qd_put(qd);
1152                         continue;
1153                 }
1154
1155                 qda[count++] = qd;
1156         }
1157
1158         if (count) {
1159                 do_sync(count, qda);
1160                 for (x = 0; x < count; x++)
1161                         qd_unlock(qda[x]);
1162         }
1163
1164         gfs2_quota_unhold(ip);
1165 }
1166
1167 #define MAX_LINE 256
1168
1169 static int print_message(struct gfs2_quota_data *qd, char *type)
1170 {
1171         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1172
1173         fs_info(sdp, "quota %s for %s %u\n",
1174                 type,
1175                 (qd->qd_id.type == USRQUOTA) ? "user" : "group",
1176                 from_kqid(&init_user_ns, qd->qd_id));
1177
1178         return 0;
1179 }
1180
1181 /**
1182  * gfs2_quota_check - check if allocating new blocks will exceed quota
1183  * @ip:  The inode for which this check is being performed
1184  * @uid: The uid to check against
1185  * @gid: The gid to check against
1186  * @ap:  The allocation parameters. ap->target contains the requested
1187  *       blocks. ap->min_target, if set, contains the minimum blks
1188  *       requested.
1189  *
1190  * Returns: 0 on success.
1191  *                  min_req = ap->min_target ? ap->min_target : ap->target;
1192  *                  quota must allow at least min_req blks for success and
1193  *                  ap->allowed is set to the number of blocks allowed
1194  *
1195  *          -EDQUOT otherwise, quota violation. ap->allowed is set to number
1196  *                  of blocks available.
1197  */
1198 int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid,
1199                      struct gfs2_alloc_parms *ap)
1200 {
1201         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1202         struct gfs2_quota_data *qd;
1203         s64 value, warn, limit;
1204         u32 x;
1205         int error = 0;
1206
1207         ap->allowed = UINT_MAX; /* Assume we are permitted a whole lot */
1208         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1209                 return 0;
1210
1211         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1212                 qd = ip->i_qadata->qa_qd[x];
1213
1214                 if (!(qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1215                       qid_eq(qd->qd_id, make_kqid_gid(gid))))
1216                         continue;
1217
1218                 warn = (s64)be64_to_cpu(qd->qd_qb.qb_warn);
1219                 limit = (s64)be64_to_cpu(qd->qd_qb.qb_limit);
1220                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1221                 spin_lock(&qd_lock);
1222                 value += qd->qd_change;
1223                 spin_unlock(&qd_lock);
1224
1225                 if (limit > 0 && (limit - value) < ap->allowed)
1226                         ap->allowed = limit - value;
1227                 /* If we can't meet the target */
1228                 if (limit && limit < (value + (s64)ap->target)) {
1229                         /* If no min_target specified or we don't meet
1230                          * min_target, return -EDQUOT */
1231                         if (!ap->min_target || ap->min_target > ap->allowed) {
1232                                 if (!test_and_set_bit(QDF_QMSG_QUIET,
1233                                                       &qd->qd_flags)) {
1234                                         print_message(qd, "exceeded");
1235                                         quota_send_warning(qd->qd_id,
1236                                                            sdp->sd_vfs->s_dev,
1237                                                            QUOTA_NL_BHARDWARN);
1238                                 }
1239                                 error = -EDQUOT;
1240                                 break;
1241                         }
1242                 } else if (warn && warn < value &&
1243                            time_after_eq(jiffies, qd->qd_last_warn +
1244                                          gfs2_tune_get(sdp, gt_quota_warn_period)
1245                                          * HZ)) {
1246                         quota_send_warning(qd->qd_id,
1247                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1248                         error = print_message(qd, "warning");
1249                         qd->qd_last_warn = jiffies;
1250                 }
1251         }
1252         return error;
1253 }
1254
1255 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1256                        kuid_t uid, kgid_t gid)
1257 {
1258         struct gfs2_quota_data *qd;
1259         u32 x;
1260         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1261
1262         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON ||
1263             gfs2_assert_warn(sdp, change))
1264                 return;
1265         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1266                 return;
1267
1268         if (gfs2_assert_withdraw(sdp, ip->i_qadata &&
1269                                  ip->i_qadata->qa_ref > 0))
1270                 return;
1271         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1272                 qd = ip->i_qadata->qa_qd[x];
1273
1274                 if (qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1275                     qid_eq(qd->qd_id, make_kqid_gid(gid))) {
1276                         do_qc(qd, change);
1277                 }
1278         }
1279 }
1280
1281 int gfs2_quota_sync(struct super_block *sb, int type)
1282 {
1283         struct gfs2_sbd *sdp = sb->s_fs_info;
1284         struct gfs2_quota_data **qda;
1285         unsigned int max_qd = PAGE_SIZE / sizeof(struct gfs2_holder);
1286         unsigned int num_qd;
1287         unsigned int x;
1288         int error = 0;
1289
1290         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1291         if (!qda)
1292                 return -ENOMEM;
1293
1294         mutex_lock(&sdp->sd_quota_sync_mutex);
1295         sdp->sd_quota_sync_gen++;
1296
1297         do {
1298                 num_qd = 0;
1299
1300                 for (;;) {
1301                         error = qd_fish(sdp, qda + num_qd);
1302                         if (error || !qda[num_qd])
1303                                 break;
1304                         if (++num_qd == max_qd)
1305                                 break;
1306                 }
1307
1308                 if (num_qd) {
1309                         if (!error)
1310                                 error = do_sync(num_qd, qda);
1311                         if (!error)
1312                                 for (x = 0; x < num_qd; x++)
1313                                         qda[x]->qd_sync_gen =
1314                                                 sdp->sd_quota_sync_gen;
1315
1316                         for (x = 0; x < num_qd; x++)
1317                                 qd_unlock(qda[x]);
1318                 }
1319         } while (!error && num_qd == max_qd);
1320
1321         mutex_unlock(&sdp->sd_quota_sync_mutex);
1322         kfree(qda);
1323
1324         return error;
1325 }
1326
1327 int gfs2_quota_refresh(struct gfs2_sbd *sdp, struct kqid qid)
1328 {
1329         struct gfs2_quota_data *qd;
1330         struct gfs2_holder q_gh;
1331         int error;
1332
1333         error = qd_get(sdp, qid, &qd);
1334         if (error)
1335                 return error;
1336
1337         error = do_glock(qd, FORCE, &q_gh);
1338         if (!error)
1339                 gfs2_glock_dq_uninit(&q_gh);
1340
1341         qd_put(qd);
1342         return error;
1343 }
1344
1345 int gfs2_quota_init(struct gfs2_sbd *sdp)
1346 {
1347         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1348         u64 size = i_size_read(sdp->sd_qc_inode);
1349         unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1350         unsigned int x, slot = 0;
1351         unsigned int found = 0;
1352         unsigned int hash;
1353         unsigned int bm_size;
1354         u64 dblock;
1355         u32 extlen = 0;
1356         int error;
1357
1358         if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1359                 return -EIO;
1360
1361         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1362         bm_size = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * sizeof(unsigned long));
1363         bm_size *= sizeof(unsigned long);
1364         error = -ENOMEM;
1365         sdp->sd_quota_bitmap = kzalloc(bm_size, GFP_NOFS | __GFP_NOWARN);
1366         if (sdp->sd_quota_bitmap == NULL)
1367                 sdp->sd_quota_bitmap = __vmalloc(bm_size, GFP_NOFS |
1368                                                  __GFP_ZERO, PAGE_KERNEL);
1369         if (!sdp->sd_quota_bitmap)
1370                 return error;
1371
1372         for (x = 0; x < blocks; x++) {
1373                 struct buffer_head *bh;
1374                 const struct gfs2_quota_change *qc;
1375                 unsigned int y;
1376
1377                 if (!extlen) {
1378                         int new = 0;
1379                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1380                         if (error)
1381                                 goto fail;
1382                 }
1383                 error = -EIO;
1384                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1385                 if (!bh)
1386                         goto fail;
1387                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1388                         brelse(bh);
1389                         goto fail;
1390                 }
1391
1392                 qc = (const struct gfs2_quota_change *)(bh->b_data + sizeof(struct gfs2_meta_header));
1393                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1394                      y++, slot++) {
1395                         struct gfs2_quota_data *qd;
1396                         s64 qc_change = be64_to_cpu(qc->qc_change);
1397                         u32 qc_flags = be32_to_cpu(qc->qc_flags);
1398                         enum quota_type qtype = (qc_flags & GFS2_QCF_USER) ?
1399                                                 USRQUOTA : GRPQUOTA;
1400                         struct kqid qc_id = make_kqid(&init_user_ns, qtype,
1401                                                       be32_to_cpu(qc->qc_id));
1402                         qc++;
1403                         if (!qc_change)
1404                                 continue;
1405
1406                         hash = gfs2_qd_hash(sdp, qc_id);
1407                         qd = qd_alloc(hash, sdp, qc_id);
1408                         if (qd == NULL) {
1409                                 brelse(bh);
1410                                 goto fail;
1411                         }
1412
1413                         set_bit(QDF_CHANGE, &qd->qd_flags);
1414                         qd->qd_change = qc_change;
1415                         qd->qd_slot = slot;
1416                         qd->qd_slot_count = 1;
1417
1418                         spin_lock(&qd_lock);
1419                         BUG_ON(test_and_set_bit(slot, sdp->sd_quota_bitmap));
1420                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1421                         atomic_inc(&sdp->sd_quota_count);
1422                         spin_unlock(&qd_lock);
1423
1424                         spin_lock_bucket(hash);
1425                         hlist_bl_add_head_rcu(&qd->qd_hlist, &qd_hash_table[hash]);
1426                         spin_unlock_bucket(hash);
1427
1428                         found++;
1429                 }
1430
1431                 brelse(bh);
1432                 dblock++;
1433                 extlen--;
1434         }
1435
1436         if (found)
1437                 fs_info(sdp, "found %u quota changes\n", found);
1438
1439         return 0;
1440
1441 fail:
1442         gfs2_quota_cleanup(sdp);
1443         return error;
1444 }
1445
1446 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1447 {
1448         struct list_head *head = &sdp->sd_quota_list;
1449         struct gfs2_quota_data *qd;
1450
1451         spin_lock(&qd_lock);
1452         while (!list_empty(head)) {
1453                 qd = list_last_entry(head, struct gfs2_quota_data, qd_list);
1454
1455                 list_del(&qd->qd_list);
1456
1457                 /* Also remove if this qd exists in the reclaim list */
1458                 list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
1459                 atomic_dec(&sdp->sd_quota_count);
1460                 spin_unlock(&qd_lock);
1461
1462                 spin_lock_bucket(qd->qd_hash);
1463                 hlist_bl_del_rcu(&qd->qd_hlist);
1464                 spin_unlock_bucket(qd->qd_hash);
1465
1466                 gfs2_assert_warn(sdp, !qd->qd_change);
1467                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1468                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1469
1470                 gfs2_glock_put(qd->qd_gl);
1471                 call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
1472
1473                 spin_lock(&qd_lock);
1474         }
1475         spin_unlock(&qd_lock);
1476
1477         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1478
1479         kvfree(sdp->sd_quota_bitmap);
1480         sdp->sd_quota_bitmap = NULL;
1481 }
1482
1483 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1484 {
1485         if (error == 0 || error == -EROFS)
1486                 return;
1487         if (!gfs2_withdrawn(sdp)) {
1488                 if (!cmpxchg(&sdp->sd_log_error, 0, error))
1489                         fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1490                 wake_up(&sdp->sd_logd_waitq);
1491         }
1492 }
1493
1494 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1495                                int (*fxn)(struct super_block *sb, int type),
1496                                unsigned long t, unsigned long *timeo,
1497                                unsigned int *new_timeo)
1498 {
1499         if (t >= *timeo) {
1500                 int error = fxn(sdp->sd_vfs, 0);
1501                 quotad_error(sdp, msg, error);
1502                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1503         } else {
1504                 *timeo -= t;
1505         }
1506 }
1507
1508 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1509 {
1510         struct gfs2_inode *ip;
1511
1512         while(1) {
1513                 ip = NULL;
1514                 spin_lock(&sdp->sd_trunc_lock);
1515                 if (!list_empty(&sdp->sd_trunc_list)) {
1516                         ip = list_first_entry(&sdp->sd_trunc_list,
1517                                         struct gfs2_inode, i_trunc_list);
1518                         list_del_init(&ip->i_trunc_list);
1519                 }
1520                 spin_unlock(&sdp->sd_trunc_lock);
1521                 if (ip == NULL)
1522                         return;
1523                 gfs2_glock_finish_truncate(ip);
1524         }
1525 }
1526
1527 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1528         if (!sdp->sd_statfs_force_sync) {
1529                 sdp->sd_statfs_force_sync = 1;
1530                 wake_up(&sdp->sd_quota_wait);
1531         }
1532 }
1533
1534
1535 /**
1536  * gfs2_quotad - Write cached quota changes into the quota file
1537  * @sdp: Pointer to GFS2 superblock
1538  *
1539  */
1540
1541 int gfs2_quotad(void *data)
1542 {
1543         struct gfs2_sbd *sdp = data;
1544         struct gfs2_tune *tune = &sdp->sd_tune;
1545         unsigned long statfs_timeo = 0;
1546         unsigned long quotad_timeo = 0;
1547         unsigned long t = 0;
1548         DEFINE_WAIT(wait);
1549         int empty;
1550
1551         while (!kthread_should_stop()) {
1552
1553                 if (gfs2_withdrawn(sdp))
1554                         goto bypass;
1555                 /* Update the master statfs file */
1556                 if (sdp->sd_statfs_force_sync) {
1557                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1558                         quotad_error(sdp, "statfs", error);
1559                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1560                 }
1561                 else
1562                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1563                                            &statfs_timeo,
1564                                            &tune->gt_statfs_quantum);
1565
1566                 /* Update quota file */
1567                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1568                                    &quotad_timeo, &tune->gt_quota_quantum);
1569
1570                 /* Check for & recover partially truncated inodes */
1571                 quotad_check_trunc_list(sdp);
1572
1573                 try_to_freeze();
1574
1575 bypass:
1576                 t = min(quotad_timeo, statfs_timeo);
1577
1578                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1579                 spin_lock(&sdp->sd_trunc_lock);
1580                 empty = list_empty(&sdp->sd_trunc_list);
1581                 spin_unlock(&sdp->sd_trunc_lock);
1582                 if (empty && !sdp->sd_statfs_force_sync)
1583                         t -= schedule_timeout(t);
1584                 else
1585                         t = 0;
1586                 finish_wait(&sdp->sd_quota_wait, &wait);
1587         }
1588
1589         return 0;
1590 }
1591
1592 static int gfs2_quota_get_state(struct super_block *sb, struct qc_state *state)
1593 {
1594         struct gfs2_sbd *sdp = sb->s_fs_info;
1595
1596         memset(state, 0, sizeof(*state));
1597
1598         switch (sdp->sd_args.ar_quota) {
1599         case GFS2_QUOTA_ON:
1600                 state->s_state[USRQUOTA].flags |= QCI_LIMITS_ENFORCED;
1601                 state->s_state[GRPQUOTA].flags |= QCI_LIMITS_ENFORCED;
1602                 /*FALLTHRU*/
1603         case GFS2_QUOTA_ACCOUNT:
1604                 state->s_state[USRQUOTA].flags |= QCI_ACCT_ENABLED |
1605                                                   QCI_SYSFILE;
1606                 state->s_state[GRPQUOTA].flags |= QCI_ACCT_ENABLED |
1607                                                   QCI_SYSFILE;
1608                 break;
1609         case GFS2_QUOTA_OFF:
1610                 break;
1611         }
1612         if (sdp->sd_quota_inode) {
1613                 state->s_state[USRQUOTA].ino =
1614                                         GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1615                 state->s_state[USRQUOTA].blocks = sdp->sd_quota_inode->i_blocks;
1616         }
1617         state->s_state[USRQUOTA].nextents = 1;  /* unsupported */
1618         state->s_state[GRPQUOTA] = state->s_state[USRQUOTA];
1619         state->s_incoredqs = list_lru_count(&gfs2_qd_lru);
1620         return 0;
1621 }
1622
1623 static int gfs2_get_dqblk(struct super_block *sb, struct kqid qid,
1624                           struct qc_dqblk *fdq)
1625 {
1626         struct gfs2_sbd *sdp = sb->s_fs_info;
1627         struct gfs2_quota_lvb *qlvb;
1628         struct gfs2_quota_data *qd;
1629         struct gfs2_holder q_gh;
1630         int error;
1631
1632         memset(fdq, 0, sizeof(*fdq));
1633
1634         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1635                 return -ESRCH; /* Crazy XFS error code */
1636
1637         if ((qid.type != USRQUOTA) &&
1638             (qid.type != GRPQUOTA))
1639                 return -EINVAL;
1640
1641         error = qd_get(sdp, qid, &qd);
1642         if (error)
1643                 return error;
1644         error = do_glock(qd, FORCE, &q_gh);
1645         if (error)
1646                 goto out;
1647
1648         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1649         fdq->d_spc_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_sb.sb_bsize_shift;
1650         fdq->d_spc_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_sb.sb_bsize_shift;
1651         fdq->d_space = be64_to_cpu(qlvb->qb_value) << sdp->sd_sb.sb_bsize_shift;
1652
1653         gfs2_glock_dq_uninit(&q_gh);
1654 out:
1655         qd_put(qd);
1656         return error;
1657 }
1658
1659 /* GFS2 only supports a subset of the XFS fields */
1660 #define GFS2_FIELDMASK (QC_SPC_SOFT|QC_SPC_HARD|QC_SPACE)
1661
1662 static int gfs2_set_dqblk(struct super_block *sb, struct kqid qid,
1663                           struct qc_dqblk *fdq)
1664 {
1665         struct gfs2_sbd *sdp = sb->s_fs_info;
1666         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1667         struct gfs2_quota_data *qd;
1668         struct gfs2_holder q_gh, i_gh;
1669         unsigned int data_blocks, ind_blocks;
1670         unsigned int blocks = 0;
1671         int alloc_required;
1672         loff_t offset;
1673         int error;
1674
1675         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1676                 return -ESRCH; /* Crazy XFS error code */
1677
1678         if ((qid.type != USRQUOTA) &&
1679             (qid.type != GRPQUOTA))
1680                 return -EINVAL;
1681
1682         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1683                 return -EINVAL;
1684
1685         error = qd_get(sdp, qid, &qd);
1686         if (error)
1687                 return error;
1688
1689         error = gfs2_qa_get(ip);
1690         if (error)
1691                 goto out_put;
1692
1693         inode_lock(&ip->i_inode);
1694         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1695         if (error)
1696                 goto out_unlockput;
1697         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1698         if (error)
1699                 goto out_q;
1700
1701         /* Check for existing entry, if none then alloc new blocks */
1702         error = update_qd(sdp, qd);
1703         if (error)
1704                 goto out_i;
1705
1706         /* If nothing has changed, this is a no-op */
1707         if ((fdq->d_fieldmask & QC_SPC_SOFT) &&
1708             ((fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1709                 fdq->d_fieldmask ^= QC_SPC_SOFT;
1710
1711         if ((fdq->d_fieldmask & QC_SPC_HARD) &&
1712             ((fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1713                 fdq->d_fieldmask ^= QC_SPC_HARD;
1714
1715         if ((fdq->d_fieldmask & QC_SPACE) &&
1716             ((fdq->d_space >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1717                 fdq->d_fieldmask ^= QC_SPACE;
1718
1719         if (fdq->d_fieldmask == 0)
1720                 goto out_i;
1721
1722         offset = qd2offset(qd);
1723         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1724         if (gfs2_is_stuffed(ip))
1725                 alloc_required = 1;
1726         if (alloc_required) {
1727                 struct gfs2_alloc_parms ap = { .aflags = 0, };
1728                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1729                                        &data_blocks, &ind_blocks);
1730                 blocks = 1 + data_blocks + ind_blocks;
1731                 ap.target = blocks;
1732                 error = gfs2_inplace_reserve(ip, &ap);
1733                 if (error)
1734                         goto out_i;
1735                 blocks += gfs2_rg_blocks(ip, blocks);
1736         }
1737
1738         /* Some quotas span block boundaries and can update two blocks,
1739            adding an extra block to the transaction to handle such quotas */
1740         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1741         if (error)
1742                 goto out_release;
1743
1744         /* Apply changes */
1745         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1746         if (!error)
1747                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
1748
1749         gfs2_trans_end(sdp);
1750 out_release:
1751         if (alloc_required)
1752                 gfs2_inplace_release(ip);
1753 out_i:
1754         gfs2_glock_dq_uninit(&i_gh);
1755 out_q:
1756         gfs2_glock_dq_uninit(&q_gh);
1757 out_unlockput:
1758         gfs2_qa_put(ip);
1759         inode_unlock(&ip->i_inode);
1760 out_put:
1761         qd_put(qd);
1762         return error;
1763 }
1764
1765 const struct quotactl_ops gfs2_quotactl_ops = {
1766         .quota_sync     = gfs2_quota_sync,
1767         .get_state      = gfs2_quota_get_state,
1768         .get_dqblk      = gfs2_get_dqblk,
1769         .set_dqblk      = gfs2_set_dqblk,
1770 };
1771
1772 void __init gfs2_quota_hash_init(void)
1773 {
1774         unsigned i;
1775
1776         for(i = 0; i < GFS2_QD_HASH_SIZE; i++)
1777                 INIT_HLIST_BL_HEAD(&qd_hash_table[i]);
1778 }