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 #include <linux/sched.h>
  40 #include <linux/slab.h>
  41 #include <linux/mm.h>
  42 #include <linux/spinlock.h>
  43 #include <linux/completion.h>
  44 #include <linux/buffer_head.h>
  45 #include <linux/sort.h>
  46 #include <linux/fs.h>
  47 #include <linux/bio.h>
  48 #include <linux/gfs2_ondisk.h>
  49 #include <linux/kthread.h>
  50 #include <linux/freezer.h>
  51 #include <linux/quota.h>
  52 #include <linux/dqblk_xfs.h>
  53
  54 #include "gfs2.h"
  55 #include "incore.h"
  56 #include "bmap.h"
  57 #include "glock.h"
  58 #include "glops.h"
  59 #include "log.h"
  60 #include "meta_io.h"
  61 #include "quota.h"
  62 #include "rgrp.h"
  63 #include "super.h"
  64 #include "trans.h"
  65 #include "inode.h"
  66 #include "util.h"
  67
  68 #define QUOTA_USER 1
  69 #define QUOTA_GROUP 0
  70
  71 struct gfs2_quota_change_host {
  72         u64 qc_change;
  73         u32 qc_flags; /* GFS2_QCF_... */
  74         u32 qc_id;
  75 };
  76
  77 static LIST_HEAD(qd_lru_list);
  78 static atomic_t qd_lru_count = ATOMIC_INIT(0);
  79 static DEFINE_SPINLOCK(qd_lru_lock);
  80
  81 int gfs2_shrink_qd_memory(struct shrinker *shrink, struct shrink_control *sc)
  82 {
  83         struct gfs2_quota_data *qd;
  84         struct gfs2_sbd *sdp;
  85         int nr_to_scan = sc->nr_to_scan;
  86
  87         if (nr_to_scan == 0)
  88                 goto out;
  89
  90         if (!(sc->gfp_mask & __GFP_FS))
  91                 return -1;
  92
  93         spin_lock(&qd_lru_lock);
  94         while (nr_to_scan && !list_empty(&qd_lru_list)) {
  95                 qd = list_entry(qd_lru_list.next,
  96                                 struct gfs2_quota_data, qd_reclaim);
  97                 sdp = qd->qd_gl->gl_sbd;
  98
  99                 /* Free from the filesystem-specific list */
 100                 list_del(&qd->qd_list);
 101
 102                 gfs2_assert_warn(sdp, !qd->qd_change);
 103                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
 104                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
 105
 106                 gfs2_glock_put(qd->qd_gl);
 107                 atomic_dec(&sdp->sd_quota_count);
 108
 109                 /* Delete it from the common reclaim list */
 110                 list_del_init(&qd->qd_reclaim);
 111                 atomic_dec(&qd_lru_count);
 112                 spin_unlock(&qd_lru_lock);
 113                 kmem_cache_free(gfs2_quotad_cachep, qd);
 114                 spin_lock(&qd_lru_lock);
 115                 nr_to_scan--;
 116         }
 117         spin_unlock(&qd_lru_lock);
 118
 119 out:
 120         return (atomic_read(&qd_lru_count) * sysctl_vfs_cache_pressure) / 100;
 121 }
 122
 123 static u64 qd2offset(struct gfs2_quota_data *qd)
 124 {
 125         u64 offset;
 126
 127         offset = 2 * (u64)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
 128         offset *= sizeof(struct gfs2_quota);
 129
 130         return offset;
 131 }
 132
 133 static int qd_alloc(struct gfs2_sbd *sdp, int user, u32 id,
 134                     struct gfs2_quota_data **qdp)
 135 {
 136         struct gfs2_quota_data *qd;
 137         int error;
 138
 139         qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
 140         if (!qd)
 141                 return -ENOMEM;
 142
 143         atomic_set(&qd->qd_count, 1);
 144         qd->qd_id = id;
 145         if (user)
 146                 set_bit(QDF_USER, &qd->qd_flags);
 147         qd->qd_slot = -1;
 148         INIT_LIST_HEAD(&qd->qd_reclaim);
 149
 150         error = gfs2_glock_get(sdp, 2 * (u64)id + !user,
 151                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
 152         if (error)
 153                 goto fail;
 154
 155         *qdp = qd;
 156
 157         return 0;
 158
 159 fail:
 160         kmem_cache_free(gfs2_quotad_cachep, qd);
 161         return error;
 162 }
 163
 164 static int qd_get(struct gfs2_sbd *sdp, int user, u32 id,
 165                   struct gfs2_quota_data **qdp)
 166 {
 167         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
 168         int error, found;
 169
 170         *qdp = NULL;
 171
 172         for (;;) {
 173                 found = 0;
 174                 spin_lock(&qd_lru_lock);
 175                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 176                         if (qd->qd_id == id &&
 177                             !test_bit(QDF_USER, &qd->qd_flags) == !user) {
 178                                 if (!atomic_read(&qd->qd_count) &&
 179                                     !list_empty(&qd->qd_reclaim)) {
 180                                         /* Remove it from reclaim list */
 181                                         list_del_init(&qd->qd_reclaim);
 182                                         atomic_dec(&qd_lru_count);
 183                                 }
 184                                 atomic_inc(&qd->qd_count);
 185                                 found = 1;
 186                                 break;
 187                         }
 188                 }
 189
 190                 if (!found)
 191                         qd = NULL;
 192
 193                 if (!qd && new_qd) {
 194                         qd = new_qd;
 195                         list_add(&qd->qd_list, &sdp->sd_quota_list);
 196                         atomic_inc(&sdp->sd_quota_count);
 197                         new_qd = NULL;
 198                 }
 199
 200                 spin_unlock(&qd_lru_lock);
 201
 202                 if (qd) {
 203                         if (new_qd) {
 204                                 gfs2_glock_put(new_qd->qd_gl);
 205                                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
 206                         }
 207                         *qdp = qd;
 208                         return 0;
 209                 }
 210
 211                 error = qd_alloc(sdp, user, id, &new_qd);
 212                 if (error)
 213                         return error;
 214         }
 215 }
 216
 217 static void qd_hold(struct gfs2_quota_data *qd)
 218 {
 219         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 220         gfs2_assert(sdp, atomic_read(&qd->qd_count));
 221         atomic_inc(&qd->qd_count);
 222 }
 223
 224 static void qd_put(struct gfs2_quota_data *qd)
 225 {
 226         if (atomic_dec_and_lock(&qd->qd_count, &qd_lru_lock)) {
 227                 /* Add to the reclaim list */
 228                 list_add_tail(&qd->qd_reclaim, &qd_lru_list);
 229                 atomic_inc(&qd_lru_count);
 230                 spin_unlock(&qd_lru_lock);
 231         }
 232 }
 233
 234 static int slot_get(struct gfs2_quota_data *qd)
 235 {
 236         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 237         unsigned int c, o = 0, b;
 238         unsigned char byte = 0;
 239
 240         spin_lock(&qd_lru_lock);
 241
 242         if (qd->qd_slot_count++) {
 243                 spin_unlock(&qd_lru_lock);
 244                 return 0;
 245         }
 246
 247         for (c = 0; c < sdp->sd_quota_chunks; c++)
 248                 for (o = 0; o < PAGE_SIZE; o++) {
 249                         byte = sdp->sd_quota_bitmap[c][o];
 250                         if (byte != 0xFF)
 251                                 goto found;
 252                 }
 253
 254         goto fail;
 255
 256 found:
 257         for (b = 0; b < 8; b++)
 258                 if (!(byte & (1 << b)))
 259                         break;
 260         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
 261
 262         if (qd->qd_slot >= sdp->sd_quota_slots)
 263                 goto fail;
 264
 265         sdp->sd_quota_bitmap[c][o] |= 1 << b;
 266
 267         spin_unlock(&qd_lru_lock);
 268
 269         return 0;
 270
 271 fail:
 272         qd->qd_slot_count--;
 273         spin_unlock(&qd_lru_lock);
 274         return -ENOSPC;
 275 }
 276
 277 static void slot_hold(struct gfs2_quota_data *qd)
 278 {
 279         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 280
 281         spin_lock(&qd_lru_lock);
 282         gfs2_assert(sdp, qd->qd_slot_count);
 283         qd->qd_slot_count++;
 284         spin_unlock(&qd_lru_lock);
 285 }
 286
 287 static void slot_put(struct gfs2_quota_data *qd)
 288 {
 289         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 290
 291         spin_lock(&qd_lru_lock);
 292         gfs2_assert(sdp, qd->qd_slot_count);
 293         if (!--qd->qd_slot_count) {
 294                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
 295                 qd->qd_slot = -1;
 296         }
 297         spin_unlock(&qd_lru_lock);
 298 }
 299
 300 static int bh_get(struct gfs2_quota_data *qd)
 301 {
 302         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 303         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 304         unsigned int block, offset;
 305         struct buffer_head *bh;
 306         int error;
 307         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
 308
 309         mutex_lock(&sdp->sd_quota_mutex);
 310
 311         if (qd->qd_bh_count++) {
 312                 mutex_unlock(&sdp->sd_quota_mutex);
 313                 return 0;
 314         }
 315
 316         block = qd->qd_slot / sdp->sd_qc_per_block;
 317         offset = qd->qd_slot % sdp->sd_qc_per_block;
 318
 319         bh_map.b_size = 1 << ip->i_inode.i_blkbits;
 320         error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
 321         if (error)
 322                 goto fail;
 323         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
 324         if (error)
 325                 goto fail;
 326         error = -EIO;
 327         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
 328                 goto fail_brelse;
 329
 330         qd->qd_bh = bh;
 331         qd->qd_bh_qc = (struct gfs2_quota_change *)
 332                 (bh->b_data + sizeof(struct gfs2_meta_header) +
 333                  offset * sizeof(struct gfs2_quota_change));
 334
 335         mutex_unlock(&sdp->sd_quota_mutex);
 336
 337         return 0;
 338
 339 fail_brelse:
 340         brelse(bh);
 341 fail:
 342         qd->qd_bh_count--;
 343         mutex_unlock(&sdp->sd_quota_mutex);
 344         return error;
 345 }
 346
 347 static void bh_put(struct gfs2_quota_data *qd)
 348 {
 349         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 350
 351         mutex_lock(&sdp->sd_quota_mutex);
 352         gfs2_assert(sdp, qd->qd_bh_count);
 353         if (!--qd->qd_bh_count) {
 354                 brelse(qd->qd_bh);
 355                 qd->qd_bh = NULL;
 356                 qd->qd_bh_qc = NULL;
 357         }
 358         mutex_unlock(&sdp->sd_quota_mutex);
 359 }
 360
 361 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
 362 {
 363         struct gfs2_quota_data *qd = NULL;
 364         int error;
 365         int found = 0;
 366
 367         *qdp = NULL;
 368
 369         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 370                 return 0;
 371
 372         spin_lock(&qd_lru_lock);
 373
 374         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 375                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 376                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
 377                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
 378                         continue;
 379
 380                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 381
 382                 set_bit(QDF_LOCKED, &qd->qd_flags);
 383                 gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
 384                 atomic_inc(&qd->qd_count);
 385                 qd->qd_change_sync = qd->qd_change;
 386                 gfs2_assert_warn(sdp, qd->qd_slot_count);
 387                 qd->qd_slot_count++;
 388                 found = 1;
 389
 390                 break;
 391         }
 392
 393         if (!found)
 394                 qd = NULL;
 395
 396         spin_unlock(&qd_lru_lock);
 397
 398         if (qd) {
 399                 gfs2_assert_warn(sdp, qd->qd_change_sync);
 400                 error = bh_get(qd);
 401                 if (error) {
 402                         clear_bit(QDF_LOCKED, &qd->qd_flags);
 403                         slot_put(qd);
 404                         qd_put(qd);
 405                         return error;
 406                 }
 407         }
 408
 409         *qdp = qd;
 410
 411         return 0;
 412 }
 413
 414 static int qd_trylock(struct gfs2_quota_data *qd)
 415 {
 416         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 417
 418         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 419                 return 0;
 420
 421         spin_lock(&qd_lru_lock);
 422
 423         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 424             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
 425                 spin_unlock(&qd_lru_lock);
 426                 return 0;
 427         }
 428
 429         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 430
 431         set_bit(QDF_LOCKED, &qd->qd_flags);
 432         gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
 433         atomic_inc(&qd->qd_count);
 434         qd->qd_change_sync = qd->qd_change;
 435         gfs2_assert_warn(sdp, qd->qd_slot_count);
 436         qd->qd_slot_count++;
 437
 438         spin_unlock(&qd_lru_lock);
 439
 440         gfs2_assert_warn(sdp, qd->qd_change_sync);
 441         if (bh_get(qd)) {
 442                 clear_bit(QDF_LOCKED, &qd->qd_flags);
 443                 slot_put(qd);
 444                 qd_put(qd);
 445                 return 0;
 446         }
 447
 448         return 1;
 449 }
 450
 451 static void qd_unlock(struct gfs2_quota_data *qd)
 452 {
 453         gfs2_assert_warn(qd->qd_gl->gl_sbd,
 454                          test_bit(QDF_LOCKED, &qd->qd_flags));
 455         clear_bit(QDF_LOCKED, &qd->qd_flags);
 456         bh_put(qd);
 457         slot_put(qd);
 458         qd_put(qd);
 459 }
 460
 461 static int qdsb_get(struct gfs2_sbd *sdp, int user, u32 id,
 462                     struct gfs2_quota_data **qdp)
 463 {
 464         int error;
 465
 466         error = qd_get(sdp, user, id, qdp);
 467         if (error)
 468                 return error;
 469
 470         error = slot_get(*qdp);
 471         if (error)
 472                 goto fail;
 473
 474         error = bh_get(*qdp);
 475         if (error)
 476                 goto fail_slot;
 477
 478         return 0;
 479
 480 fail_slot:
 481         slot_put(*qdp);
 482 fail:
 483         qd_put(*qdp);
 484         return error;
 485 }
 486
 487 static void qdsb_put(struct gfs2_quota_data *qd)
 488 {
 489         bh_put(qd);
 490         slot_put(qd);
 491         qd_put(qd);
 492 }
 493
 494 int gfs2_quota_hold(struct gfs2_inode *ip, u32 uid, u32 gid)
 495 {
 496         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 497         struct gfs2_alloc *al = ip->i_alloc;
 498         struct gfs2_quota_data **qd = al->al_qd;
 499         int error;
 500
 501         if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
 502             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
 503                 return -EIO;
 504
 505         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 506                 return 0;
 507
 508         error = qdsb_get(sdp, QUOTA_USER, ip->i_inode.i_uid, qd);
 509         if (error)
 510                 goto out;
 511         al->al_qd_num++;
 512         qd++;
 513
 514         error = qdsb_get(sdp, QUOTA_GROUP, ip->i_inode.i_gid, qd);
 515         if (error)
 516                 goto out;
 517         al->al_qd_num++;
 518         qd++;
 519
 520         if (uid != NO_QUOTA_CHANGE && uid != ip->i_inode.i_uid) {
 521                 error = qdsb_get(sdp, QUOTA_USER, uid, qd);
 522                 if (error)
 523                         goto out;
 524                 al->al_qd_num++;
 525                 qd++;
 526         }
 527
 528         if (gid != NO_QUOTA_CHANGE && gid != ip->i_inode.i_gid) {
 529                 error = qdsb_get(sdp, QUOTA_GROUP, gid, qd);
 530                 if (error)
 531                         goto out;
 532                 al->al_qd_num++;
 533                 qd++;
 534         }
 535
 536 out:
 537         if (error)
 538                 gfs2_quota_unhold(ip);
 539         return error;
 540 }
 541
 542 void gfs2_quota_unhold(struct gfs2_inode *ip)
 543 {
 544         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 545         struct gfs2_alloc *al = ip->i_alloc;
 546         unsigned int x;
 547
 548         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 549
 550         for (x = 0; x < al->al_qd_num; x++) {
 551                 qdsb_put(al->al_qd[x]);
 552                 al->al_qd[x] = NULL;
 553         }
 554         al->al_qd_num = 0;
 555 }
 556
 557 static int sort_qd(const void *a, const void *b)
 558 {
 559         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
 560         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
 561
 562         if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
 563             !test_bit(QDF_USER, &qd_b->qd_flags)) {
 564                 if (test_bit(QDF_USER, &qd_a->qd_flags))
 565                         return -1;
 566                 else
 567                         return 1;
 568         }
 569         if (qd_a->qd_id < qd_b->qd_id)
 570                 return -1;
 571         if (qd_a->qd_id > qd_b->qd_id)
 572                 return 1;
 573
 574         return 0;
 575 }
 576
 577 static void do_qc(struct gfs2_quota_data *qd, s64 change)
 578 {
 579         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 580         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 581         struct gfs2_quota_change *qc = qd->qd_bh_qc;
 582         s64 x;
 583
 584         mutex_lock(&sdp->sd_quota_mutex);
 585         gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
 586
 587         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
 588                 qc->qc_change = 0;
 589                 qc->qc_flags = 0;
 590                 if (test_bit(QDF_USER, &qd->qd_flags))
 591                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
 592                 qc->qc_id = cpu_to_be32(qd->qd_id);
 593         }
 594
 595         x = be64_to_cpu(qc->qc_change) + change;
 596         qc->qc_change = cpu_to_be64(x);
 597
 598         spin_lock(&qd_lru_lock);
 599         qd->qd_change = x;
 600         spin_unlock(&qd_lru_lock);
 601
 602         if (!x) {
 603                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
 604                 clear_bit(QDF_CHANGE, &qd->qd_flags);
 605                 qc->qc_flags = 0;
 606                 qc->qc_id = 0;
 607                 slot_put(qd);
 608                 qd_put(qd);
 609         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
 610                 qd_hold(qd);
 611                 slot_hold(qd);
 612         }
 613
 614         mutex_unlock(&sdp->sd_quota_mutex);
 615 }
 616
 617 /**
 618  * gfs2_adjust_quota - adjust record of current block usage
 619  * @ip: The quota inode
 620  * @loc: Offset of the entry in the quota file
 621  * @change: The amount of usage change to record
 622  * @qd: The quota data
 623  * @fdq: The updated limits to record
 624  *
 625  * This function was mostly borrowed from gfs2_block_truncate_page which was
 626  * in turn mostly borrowed from ext3
 627  *
 628  * Returns: 0 or -ve on error
 629  */
 630
 631 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 632                              s64 change, struct gfs2_quota_data *qd,
 633                              struct fs_disk_quota *fdq)
 634 {
 635         struct inode *inode = &ip->i_inode;
 636         struct gfs2_sbd *sdp = GFS2_SB(inode);
 637         struct address_space *mapping = inode->i_mapping;
 638         unsigned long index = loc >> PAGE_CACHE_SHIFT;
 639         unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
 640         unsigned blocksize, iblock, pos;
 641         struct buffer_head *bh, *dibh;
 642         struct page *page;
 643         void *kaddr, *ptr;
 644         struct gfs2_quota q, *qp;
 645         int err, nbytes;
 646         u64 size;
 647
 648         if (gfs2_is_stuffed(ip))
 649                 gfs2_unstuff_dinode(ip, NULL);
 650
 651         memset(&q, 0, sizeof(struct gfs2_quota));
 652         err = gfs2_internal_read(ip, NULL, (char *)&q, &loc, sizeof(q));
 653         if (err < 0)
 654                 return err;
 655
 656         err = -EIO;
 657         qp = &q;
 658         qp->qu_value = be64_to_cpu(qp->qu_value);
 659         qp->qu_value += change;
 660         qp->qu_value = cpu_to_be64(qp->qu_value);
 661         qd->qd_qb.qb_value = qp->qu_value;
 662         if (fdq) {
 663                 if (fdq->d_fieldmask & FS_DQ_BSOFT) {
 664                         qp->qu_warn = cpu_to_be64(fdq->d_blk_softlimit >> sdp->sd_fsb2bb_shift);
 665                         qd->qd_qb.qb_warn = qp->qu_warn;
 666                 }
 667                 if (fdq->d_fieldmask & FS_DQ_BHARD) {
 668                         qp->qu_limit = cpu_to_be64(fdq->d_blk_hardlimit >> sdp->sd_fsb2bb_shift);
 669                         qd->qd_qb.qb_limit = qp->qu_limit;
 670                 }
 671                 if (fdq->d_fieldmask & FS_DQ_BCOUNT) {
 672                         qp->qu_value = cpu_to_be64(fdq->d_bcount >> sdp->sd_fsb2bb_shift);
 673                         qd->qd_qb.qb_value = qp->qu_value;
 674                 }
 675         }
 676
 677         /* Write the quota into the quota file on disk */
 678         ptr = qp;
 679         nbytes = sizeof(struct gfs2_quota);
 680 get_a_page:
 681         page = grab_cache_page(mapping, index);
 682         if (!page)
 683                 return -ENOMEM;
 684
 685         blocksize = inode->i_sb->s_blocksize;
 686         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
 687
 688         if (!page_has_buffers(page))
 689                 create_empty_buffers(page, blocksize, 0);
 690
 691         bh = page_buffers(page);
 692         pos = blocksize;
 693         while (offset >= pos) {
 694                 bh = bh->b_this_page;
 695                 iblock++;
 696                 pos += blocksize;
 697         }
 698
 699         if (!buffer_mapped(bh)) {
 700                 gfs2_block_map(inode, iblock, bh, 1);
 701                 if (!buffer_mapped(bh))
 702                         goto unlock_out;
 703                 /* If it's a newly allocated disk block for quota, zero it */
 704                 if (buffer_new(bh))
 705                         zero_user(page, pos - blocksize, bh->b_size);
 706         }
 707
 708         if (PageUptodate(page))
 709                 set_buffer_uptodate(bh);
 710
 711         if (!buffer_uptodate(bh)) {
 712                 ll_rw_block(READ | REQ_META | REQ_PRIO, 1, &bh);
 713                 wait_on_buffer(bh);
 714                 if (!buffer_uptodate(bh))
 715                         goto unlock_out;
 716         }
 717
 718         gfs2_trans_add_bh(ip->i_gl, bh, 0);
 719
 720         kaddr = kmap_atomic(page, KM_USER0);
 721         if (offset + sizeof(struct gfs2_quota) > PAGE_CACHE_SIZE)
 722                 nbytes = PAGE_CACHE_SIZE - offset;
 723         memcpy(kaddr + offset, ptr, nbytes);
 724         flush_dcache_page(page);
 725         kunmap_atomic(kaddr, KM_USER0);
 726         unlock_page(page);
 727         page_cache_release(page);
 728
 729         /* If quota straddles page boundary, we need to update the rest of the
 730          * quota at the beginning of the next page */
 731         if ((offset + sizeof(struct gfs2_quota)) > PAGE_CACHE_SIZE) {
 732                 ptr = ptr + nbytes;
 733                 nbytes = sizeof(struct gfs2_quota) - nbytes;
 734                 offset = 0;
 735                 index++;
 736                 goto get_a_page;
 737         }
 738
 739         /* Update the disk inode timestamp and size (if extended) */
 740         err = gfs2_meta_inode_buffer(ip, &dibh);
 741         if (err)
 742                 goto out;
 743
 744         size = loc + sizeof(struct gfs2_quota);
 745         if (size > inode->i_size)
 746                 i_size_write(inode, size);
 747         inode->i_mtime = inode->i_atime = CURRENT_TIME;
 748         gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 749         gfs2_dinode_out(ip, dibh->b_data);
 750         brelse(dibh);
 751         mark_inode_dirty(inode);
 752
 753 out:
 754         return err;
 755 unlock_out:
 756         unlock_page(page);
 757         page_cache_release(page);
 758         return err;
 759 }
 760
 761 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 762 {
 763         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
 764         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 765         unsigned int data_blocks, ind_blocks;
 766         struct gfs2_holder *ghs, i_gh;
 767         unsigned int qx, x;
 768         struct gfs2_quota_data *qd;
 769         loff_t offset;
 770         unsigned int nalloc = 0, blocks;
 771         struct gfs2_alloc *al = NULL;
 772         int error;
 773
 774         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 775                               &data_blocks, &ind_blocks);
 776
 777         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
 778         if (!ghs)
 779                 return -ENOMEM;
 780
 781         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 782         mutex_lock_nested(&ip->i_inode.i_mutex, I_MUTEX_QUOTA);
 783         for (qx = 0; qx < num_qd; qx++) {
 784                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
 785                                            GL_NOCACHE, &ghs[qx]);
 786                 if (error)
 787                         goto out;
 788         }
 789
 790         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 791         if (error)
 792                 goto out;
 793
 794         for (x = 0; x < num_qd; x++) {
 795                 offset = qd2offset(qda[x]);
 796                 if (gfs2_write_alloc_required(ip, offset,
 797                                               sizeof(struct gfs2_quota)))
 798                         nalloc++;
 799         }
 800
 801         al = gfs2_alloc_get(ip);
 802         if (!al) {
 803                 error = -ENOMEM;
 804                 goto out_gunlock;
 805         }
 806         /*
 807          * 1 blk for unstuffing inode if stuffed. We add this extra
 808          * block to the reservation unconditionally. If the inode
 809          * doesn't need unstuffing, the block will be released to the
 810          * rgrp since it won't be allocated during the transaction
 811          */
 812         al->al_requested = 1;
 813         /* +3 in the end for unstuffing block, inode size update block
 814          * and another block in case quota straddles page boundary and
 815          * two blocks need to be updated instead of 1 */
 816         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
 817
 818         if (nalloc)
 819                 al->al_requested += nalloc * (data_blocks + ind_blocks);
 820         error = gfs2_inplace_reserve(ip);
 821         if (error)
 822                 goto out_alloc;
 823
 824         if (nalloc)
 825                 blocks += gfs2_rg_blocks(al) + nalloc * ind_blocks + RES_STATFS;
 826
 827         error = gfs2_trans_begin(sdp, blocks, 0);
 828         if (error)
 829                 goto out_ipres;
 830
 831         for (x = 0; x < num_qd; x++) {
 832                 qd = qda[x];
 833                 offset = qd2offset(qd);
 834                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
 835                 if (error)
 836                         goto out_end_trans;
 837
 838                 do_qc(qd, -qd->qd_change_sync);
 839                 set_bit(QDF_REFRESH, &qd->qd_flags);
 840         }
 841
 842         error = 0;
 843
 844 out_end_trans:
 845         gfs2_trans_end(sdp);
 846 out_ipres:
 847         gfs2_inplace_release(ip);
 848 out_alloc:
 849         gfs2_alloc_put(ip);
 850 out_gunlock:
 851         gfs2_glock_dq_uninit(&i_gh);
 852 out:
 853         while (qx--)
 854                 gfs2_glock_dq_uninit(&ghs[qx]);
 855         mutex_unlock(&ip->i_inode.i_mutex);
 856         kfree(ghs);
 857         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
 858         return error;
 859 }
 860
 861 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
 862 {
 863         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 864         struct gfs2_quota q;
 865         struct gfs2_quota_lvb *qlvb;
 866         loff_t pos;
 867         int error;
 868
 869         memset(&q, 0, sizeof(struct gfs2_quota));
 870         pos = qd2offset(qd);
 871         error = gfs2_internal_read(ip, NULL, (char *)&q, &pos, sizeof(q));
 872         if (error < 0)
 873                 return error;
 874
 875         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 876         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
 877         qlvb->__pad = 0;
 878         qlvb->qb_limit = q.qu_limit;
 879         qlvb->qb_warn = q.qu_warn;
 880         qlvb->qb_value = q.qu_value;
 881         qd->qd_qb = *qlvb;
 882
 883         return 0;
 884 }
 885
 886 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 887                     struct gfs2_holder *q_gh)
 888 {
 889         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 890         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 891         struct gfs2_holder i_gh;
 892         int error;
 893
 894 restart:
 895         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 896         if (error)
 897                 return error;
 898
 899         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 900
 901         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
 902                 gfs2_glock_dq_uninit(q_gh);
 903                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
 904                                            GL_NOCACHE, q_gh);
 905                 if (error)
 906                         return error;
 907
 908                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
 909                 if (error)
 910                         goto fail;
 911
 912                 error = update_qd(sdp, qd);
 913                 if (error)
 914                         goto fail_gunlock;
 915
 916                 gfs2_glock_dq_uninit(&i_gh);
 917                 gfs2_glock_dq_uninit(q_gh);
 918                 force_refresh = 0;
 919                 goto restart;
 920         }
 921
 922         return 0;
 923
 924 fail_gunlock:
 925         gfs2_glock_dq_uninit(&i_gh);
 926 fail:
 927         gfs2_glock_dq_uninit(q_gh);
 928         return error;
 929 }
 930
 931 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
 932 {
 933         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 934         struct gfs2_alloc *al = ip->i_alloc;
 935         struct gfs2_quota_data *qd;
 936         unsigned int x;
 937         int error = 0;
 938
 939         gfs2_quota_hold(ip, uid, gid);
 940
 941         if (capable(CAP_SYS_RESOURCE) ||
 942             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 943                 return 0;
 944
 945         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
 946              sort_qd, NULL);
 947
 948         for (x = 0; x < al->al_qd_num; x++) {
 949                 int force = NO_FORCE;
 950                 qd = al->al_qd[x];
 951                 if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
 952                         force = FORCE;
 953                 error = do_glock(qd, force, &al->al_qd_ghs[x]);
 954                 if (error)
 955                         break;
 956         }
 957
 958         if (!error)
 959                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
 960         else {
 961                 while (x--)
 962                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 963                 gfs2_quota_unhold(ip);
 964         }
 965
 966         return error;
 967 }
 968
 969 static int need_sync(struct gfs2_quota_data *qd)
 970 {
 971         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 972         struct gfs2_tune *gt = &sdp->sd_tune;
 973         s64 value;
 974         unsigned int num, den;
 975         int do_sync = 1;
 976
 977         if (!qd->qd_qb.qb_limit)
 978                 return 0;
 979
 980         spin_lock(&qd_lru_lock);
 981         value = qd->qd_change;
 982         spin_unlock(&qd_lru_lock);
 983
 984         spin_lock(&gt->gt_spin);
 985         num = gt->gt_quota_scale_num;
 986         den = gt->gt_quota_scale_den;
 987         spin_unlock(&gt->gt_spin);
 988
 989         if (value < 0)
 990                 do_sync = 0;
 991         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
 992                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 993                 do_sync = 0;
 994         else {
 995                 value *= gfs2_jindex_size(sdp) * num;
 996                 value = div_s64(value, den);
 997                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
 998                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 999                         do_sync = 0;
1000         }
1001
1002         return do_sync;
1003 }
1004
1005 void gfs2_quota_unlock(struct gfs2_inode *ip)
1006 {
1007         struct gfs2_alloc *al = ip->i_alloc;
1008         struct gfs2_quota_data *qda[4];
1009         unsigned int count = 0;
1010         unsigned int x;
1011
1012         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1013                 goto out;
1014
1015         for (x = 0; x < al->al_qd_num; x++) {
1016                 struct gfs2_quota_data *qd;
1017                 int sync;
1018
1019                 qd = al->al_qd[x];
1020                 sync = need_sync(qd);
1021
1022                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
1023
1024                 if (sync && qd_trylock(qd))
1025                         qda[count++] = qd;
1026         }
1027
1028         if (count) {
1029                 do_sync(count, qda);
1030                 for (x = 0; x < count; x++)
1031                         qd_unlock(qda[x]);
1032         }
1033
1034 out:
1035         gfs2_quota_unhold(ip);
1036 }
1037
1038 #define MAX_LINE 256
1039
1040 static int print_message(struct gfs2_quota_data *qd, char *type)
1041 {
1042         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1043
1044         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\n",
1045                sdp->sd_fsname, type,
1046                (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
1047                qd->qd_id);
1048
1049         return 0;
1050 }
1051
1052 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
1053 {
1054         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1055         struct gfs2_alloc *al = ip->i_alloc;
1056         struct gfs2_quota_data *qd;
1057         s64 value;
1058         unsigned int x;
1059         int error = 0;
1060
1061         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1062                 return 0;
1063
1064         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1065                 return 0;
1066
1067         for (x = 0; x < al->al_qd_num; x++) {
1068                 qd = al->al_qd[x];
1069
1070                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1071                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
1072                         continue;
1073
1074                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1075                 spin_lock(&qd_lru_lock);
1076                 value += qd->qd_change;
1077                 spin_unlock(&qd_lru_lock);
1078
1079                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
1080                         print_message(qd, "exceeded");
1081                         quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1082                                            USRQUOTA : GRPQUOTA, qd->qd_id,
1083                                            sdp->sd_vfs->s_dev, QUOTA_NL_BHARDWARN);
1084
1085                         error = -EDQUOT;
1086                         break;
1087                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
1088                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
1089                            time_after_eq(jiffies, qd->qd_last_warn +
1090                                          gfs2_tune_get(sdp,
1091                                                 gt_quota_warn_period) * HZ)) {
1092                         quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1093                                            USRQUOTA : GRPQUOTA, qd->qd_id,
1094                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1095                         error = print_message(qd, "warning");
1096                         qd->qd_last_warn = jiffies;
1097                 }
1098         }
1099
1100         return error;
1101 }
1102
1103 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1104                        u32 uid, u32 gid)
1105 {
1106         struct gfs2_alloc *al = ip->i_alloc;
1107         struct gfs2_quota_data *qd;
1108         unsigned int x;
1109
1110         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1111                 return;
1112         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1113                 return;
1114
1115         for (x = 0; x < al->al_qd_num; x++) {
1116                 qd = al->al_qd[x];
1117
1118                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1119                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
1120                         do_qc(qd, change);
1121                 }
1122         }
1123 }
1124
1125 int gfs2_quota_sync(struct super_block *sb, int type, int wait)
1126 {
1127         struct gfs2_sbd *sdp = sb->s_fs_info;
1128         struct gfs2_quota_data **qda;
1129         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1130         unsigned int num_qd;
1131         unsigned int x;
1132         int error = 0;
1133
1134         sdp->sd_quota_sync_gen++;
1135
1136         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1137         if (!qda)
1138                 return -ENOMEM;
1139
1140         do {
1141                 num_qd = 0;
1142
1143                 for (;;) {
1144                         error = qd_fish(sdp, qda + num_qd);
1145                         if (error || !qda[num_qd])
1146                                 break;
1147                         if (++num_qd == max_qd)
1148                                 break;
1149                 }
1150
1151                 if (num_qd) {
1152                         if (!error)
1153                                 error = do_sync(num_qd, qda);
1154                         if (!error)
1155                                 for (x = 0; x < num_qd; x++)
1156                                         qda[x]->qd_sync_gen =
1157                                                 sdp->sd_quota_sync_gen;
1158
1159                         for (x = 0; x < num_qd; x++)
1160                                 qd_unlock(qda[x]);
1161                 }
1162         } while (!error && num_qd == max_qd);
1163
1164         kfree(qda);
1165
1166         return error;
1167 }
1168
1169 static int gfs2_quota_sync_timeo(struct super_block *sb, int type)
1170 {
1171         return gfs2_quota_sync(sb, type, 0);
1172 }
1173
1174 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1175 {
1176         struct gfs2_quota_data *qd;
1177         struct gfs2_holder q_gh;
1178         int error;
1179
1180         error = qd_get(sdp, user, id, &qd);
1181         if (error)
1182                 return error;
1183
1184         error = do_glock(qd, FORCE, &q_gh);
1185         if (!error)
1186                 gfs2_glock_dq_uninit(&q_gh);
1187
1188         qd_put(qd);
1189         return error;
1190 }
1191
1192 static void gfs2_quota_change_in(struct gfs2_quota_change_host *qc, const void *buf)
1193 {
1194         const struct gfs2_quota_change *str = buf;
1195
1196         qc->qc_change = be64_to_cpu(str->qc_change);
1197         qc->qc_flags = be32_to_cpu(str->qc_flags);
1198         qc->qc_id = be32_to_cpu(str->qc_id);
1199 }
1200
1201 int gfs2_quota_init(struct gfs2_sbd *sdp)
1202 {
1203         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1204         u64 size = i_size_read(sdp->sd_qc_inode);
1205         unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1206         unsigned int x, slot = 0;
1207         unsigned int found = 0;
1208         u64 dblock;
1209         u32 extlen = 0;
1210         int error;
1211
1212         if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1213                 return -EIO;
1214
1215         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1216         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1217
1218         error = -ENOMEM;
1219
1220         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1221                                        sizeof(unsigned char *), GFP_NOFS);
1222         if (!sdp->sd_quota_bitmap)
1223                 return error;
1224
1225         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1226                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_NOFS);
1227                 if (!sdp->sd_quota_bitmap[x])
1228                         goto fail;
1229         }
1230
1231         for (x = 0; x < blocks; x++) {
1232                 struct buffer_head *bh;
1233                 unsigned int y;
1234
1235                 if (!extlen) {
1236                         int new = 0;
1237                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1238                         if (error)
1239                                 goto fail;
1240                 }
1241                 error = -EIO;
1242                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1243                 if (!bh)
1244                         goto fail;
1245                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1246                         brelse(bh);
1247                         goto fail;
1248                 }
1249
1250                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1251                      y++, slot++) {
1252                         struct gfs2_quota_change_host qc;
1253                         struct gfs2_quota_data *qd;
1254
1255                         gfs2_quota_change_in(&qc, bh->b_data +
1256                                           sizeof(struct gfs2_meta_header) +
1257                                           y * sizeof(struct gfs2_quota_change));
1258                         if (!qc.qc_change)
1259                                 continue;
1260
1261                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1262                                          qc.qc_id, &qd);
1263                         if (error) {
1264                                 brelse(bh);
1265                                 goto fail;
1266                         }
1267
1268                         set_bit(QDF_CHANGE, &qd->qd_flags);
1269                         qd->qd_change = qc.qc_change;
1270                         qd->qd_slot = slot;
1271                         qd->qd_slot_count = 1;
1272
1273                         spin_lock(&qd_lru_lock);
1274                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1275                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1276                         atomic_inc(&sdp->sd_quota_count);
1277                         spin_unlock(&qd_lru_lock);
1278
1279                         found++;
1280                 }
1281
1282                 brelse(bh);
1283                 dblock++;
1284                 extlen--;
1285         }
1286
1287         if (found)
1288                 fs_info(sdp, "found %u quota changes\n", found);
1289
1290         return 0;
1291
1292 fail:
1293         gfs2_quota_cleanup(sdp);
1294         return error;
1295 }
1296
1297 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1298 {
1299         struct list_head *head = &sdp->sd_quota_list;
1300         struct gfs2_quota_data *qd;
1301         unsigned int x;
1302
1303         spin_lock(&qd_lru_lock);
1304         while (!list_empty(head)) {
1305                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1306
1307                 if (atomic_read(&qd->qd_count) > 1 ||
1308                     (atomic_read(&qd->qd_count) &&
1309                      !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1310                         list_move(&qd->qd_list, head);
1311                         spin_unlock(&qd_lru_lock);
1312                         schedule();
1313                         spin_lock(&qd_lru_lock);
1314                         continue;
1315                 }
1316
1317                 list_del(&qd->qd_list);
1318                 /* Also remove if this qd exists in the reclaim list */
1319                 if (!list_empty(&qd->qd_reclaim)) {
1320                         list_del_init(&qd->qd_reclaim);
1321                         atomic_dec(&qd_lru_count);
1322                 }
1323                 atomic_dec(&sdp->sd_quota_count);
1324                 spin_unlock(&qd_lru_lock);
1325
1326                 if (!atomic_read(&qd->qd_count)) {
1327                         gfs2_assert_warn(sdp, !qd->qd_change);
1328                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1329                 } else
1330                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1331                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1332
1333                 gfs2_glock_put(qd->qd_gl);
1334                 kmem_cache_free(gfs2_quotad_cachep, qd);
1335
1336                 spin_lock(&qd_lru_lock);
1337         }
1338         spin_unlock(&qd_lru_lock);
1339
1340         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1341
1342         if (sdp->sd_quota_bitmap) {
1343                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1344                         kfree(sdp->sd_quota_bitmap[x]);
1345                 kfree(sdp->sd_quota_bitmap);
1346         }
1347 }
1348
1349 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1350 {
1351         if (error == 0 || error == -EROFS)
1352                 return;
1353         if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1354                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1355 }
1356
1357 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1358                                int (*fxn)(struct super_block *sb, int type),
1359                                unsigned long t, unsigned long *timeo,
1360                                unsigned int *new_timeo)
1361 {
1362         if (t >= *timeo) {
1363                 int error = fxn(sdp->sd_vfs, 0);
1364                 quotad_error(sdp, msg, error);
1365                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1366         } else {
1367                 *timeo -= t;
1368         }
1369 }
1370
1371 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1372 {
1373         struct gfs2_inode *ip;
1374
1375         while(1) {
1376                 ip = NULL;
1377                 spin_lock(&sdp->sd_trunc_lock);
1378                 if (!list_empty(&sdp->sd_trunc_list)) {
1379                         ip = list_entry(sdp->sd_trunc_list.next,
1380                                         struct gfs2_inode, i_trunc_list);
1381                         list_del_init(&ip->i_trunc_list);
1382                 }
1383                 spin_unlock(&sdp->sd_trunc_lock);
1384                 if (ip == NULL)
1385                         return;
1386                 gfs2_glock_finish_truncate(ip);
1387         }
1388 }
1389
1390 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1391         if (!sdp->sd_statfs_force_sync) {
1392                 sdp->sd_statfs_force_sync = 1;
1393                 wake_up(&sdp->sd_quota_wait);
1394         }
1395 }
1396
1397
1398 /**
1399  * gfs2_quotad - Write cached quota changes into the quota file
1400  * @sdp: Pointer to GFS2 superblock
1401  *
1402  */
1403
1404 int gfs2_quotad(void *data)
1405 {
1406         struct gfs2_sbd *sdp = data;
1407         struct gfs2_tune *tune = &sdp->sd_tune;
1408         unsigned long statfs_timeo = 0;
1409         unsigned long quotad_timeo = 0;
1410         unsigned long t = 0;
1411         DEFINE_WAIT(wait);
1412         int empty;
1413
1414         while (!kthread_should_stop()) {
1415
1416                 /* Update the master statfs file */
1417                 if (sdp->sd_statfs_force_sync) {
1418                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1419                         quotad_error(sdp, "statfs", error);
1420                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1421                 }
1422                 else
1423                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1424                                            &statfs_timeo,
1425                                            &tune->gt_statfs_quantum);
1426
1427                 /* Update quota file */
1428                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync_timeo, t,
1429                                    &quotad_timeo, &tune->gt_quota_quantum);
1430
1431                 /* Check for & recover partially truncated inodes */
1432                 quotad_check_trunc_list(sdp);
1433
1434                 if (freezing(current))
1435                         refrigerator();
1436                 t = min(quotad_timeo, statfs_timeo);
1437
1438                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1439                 spin_lock(&sdp->sd_trunc_lock);
1440                 empty = list_empty(&sdp->sd_trunc_list);
1441                 spin_unlock(&sdp->sd_trunc_lock);
1442                 if (empty && !sdp->sd_statfs_force_sync)
1443                         t -= schedule_timeout(t);
1444                 else
1445                         t = 0;
1446                 finish_wait(&sdp->sd_quota_wait, &wait);
1447         }
1448
1449         return 0;
1450 }
1451
1452 static int gfs2_quota_get_xstate(struct super_block *sb,
1453                                  struct fs_quota_stat *fqs)
1454 {
1455         struct gfs2_sbd *sdp = sb->s_fs_info;
1456
1457         memset(fqs, 0, sizeof(struct fs_quota_stat));
1458         fqs->qs_version = FS_QSTAT_VERSION;
1459
1460         switch (sdp->sd_args.ar_quota) {
1461         case GFS2_QUOTA_ON:
1462                 fqs->qs_flags |= (FS_QUOTA_UDQ_ENFD | FS_QUOTA_GDQ_ENFD);
1463                 /*FALLTHRU*/
1464         case GFS2_QUOTA_ACCOUNT:
1465                 fqs->qs_flags |= (FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT);
1466                 break;
1467         case GFS2_QUOTA_OFF:
1468                 break;
1469         }
1470
1471         if (sdp->sd_quota_inode) {
1472                 fqs->qs_uquota.qfs_ino = GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1473                 fqs->qs_uquota.qfs_nblks = sdp->sd_quota_inode->i_blocks;
1474         }
1475         fqs->qs_uquota.qfs_nextents = 1; /* unsupported */
1476         fqs->qs_gquota = fqs->qs_uquota; /* its the same inode in both cases */
1477         fqs->qs_incoredqs = atomic_read(&qd_lru_count);
1478         return 0;
1479 }
1480
1481 static int gfs2_get_dqblk(struct super_block *sb, int type, qid_t id,
1482                           struct fs_disk_quota *fdq)
1483 {
1484         struct gfs2_sbd *sdp = sb->s_fs_info;
1485         struct gfs2_quota_lvb *qlvb;
1486         struct gfs2_quota_data *qd;
1487         struct gfs2_holder q_gh;
1488         int error;
1489
1490         memset(fdq, 0, sizeof(struct fs_disk_quota));
1491
1492         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1493                 return -ESRCH; /* Crazy XFS error code */
1494
1495         if (type == USRQUOTA)
1496                 type = QUOTA_USER;
1497         else if (type == GRPQUOTA)
1498                 type = QUOTA_GROUP;
1499         else
1500                 return -EINVAL;
1501
1502         error = qd_get(sdp, type, id, &qd);
1503         if (error)
1504                 return error;
1505         error = do_glock(qd, FORCE, &q_gh);
1506         if (error)
1507                 goto out;
1508
1509         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
1510         fdq->d_version = FS_DQUOT_VERSION;
1511         fdq->d_flags = (type == QUOTA_USER) ? FS_USER_QUOTA : FS_GROUP_QUOTA;
1512         fdq->d_id = id;
1513         fdq->d_blk_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_fsb2bb_shift;
1514         fdq->d_blk_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_fsb2bb_shift;
1515         fdq->d_bcount = be64_to_cpu(qlvb->qb_value) << sdp->sd_fsb2bb_shift;
1516
1517         gfs2_glock_dq_uninit(&q_gh);
1518 out:
1519         qd_put(qd);
1520         return error;
1521 }
1522
1523 /* GFS2 only supports a subset of the XFS fields */
1524 #define GFS2_FIELDMASK (FS_DQ_BSOFT|FS_DQ_BHARD|FS_DQ_BCOUNT)
1525
1526 static int gfs2_set_dqblk(struct super_block *sb, int type, qid_t id,
1527                           struct fs_disk_quota *fdq)
1528 {
1529         struct gfs2_sbd *sdp = sb->s_fs_info;
1530         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1531         struct gfs2_quota_data *qd;
1532         struct gfs2_holder q_gh, i_gh;
1533         unsigned int data_blocks, ind_blocks;
1534         unsigned int blocks = 0;
1535         int alloc_required;
1536         struct gfs2_alloc *al;
1537         loff_t offset;
1538         int error;
1539
1540         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1541                 return -ESRCH; /* Crazy XFS error code */
1542
1543         switch(type) {
1544         case USRQUOTA:
1545                 type = QUOTA_USER;
1546                 if (fdq->d_flags != FS_USER_QUOTA)
1547                         return -EINVAL;
1548                 break;
1549         case GRPQUOTA:
1550                 type = QUOTA_GROUP;
1551                 if (fdq->d_flags != FS_GROUP_QUOTA)
1552                         return -EINVAL;
1553                 break;
1554         default:
1555                 return -EINVAL;
1556         }
1557
1558         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1559                 return -EINVAL;
1560         if (fdq->d_id != id)
1561                 return -EINVAL;
1562
1563         error = qd_get(sdp, type, id, &qd);
1564         if (error)
1565                 return error;
1566
1567         mutex_lock(&ip->i_inode.i_mutex);
1568         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1569         if (error)
1570                 goto out_put;
1571         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1572         if (error)
1573                 goto out_q;
1574
1575         /* Check for existing entry, if none then alloc new blocks */
1576         error = update_qd(sdp, qd);
1577         if (error)
1578                 goto out_i;
1579
1580         /* If nothing has changed, this is a no-op */
1581         if ((fdq->d_fieldmask & FS_DQ_BSOFT) &&
1582             ((fdq->d_blk_softlimit >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1583                 fdq->d_fieldmask ^= FS_DQ_BSOFT;
1584
1585         if ((fdq->d_fieldmask & FS_DQ_BHARD) &&
1586             ((fdq->d_blk_hardlimit >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1587                 fdq->d_fieldmask ^= FS_DQ_BHARD;
1588
1589         if ((fdq->d_fieldmask & FS_DQ_BCOUNT) &&
1590             ((fdq->d_bcount >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1591                 fdq->d_fieldmask ^= FS_DQ_BCOUNT;
1592
1593         if (fdq->d_fieldmask == 0)
1594                 goto out_i;
1595
1596         offset = qd2offset(qd);
1597         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1598         if (gfs2_is_stuffed(ip))
1599                 alloc_required = 1;
1600         if (alloc_required) {
1601                 al = gfs2_alloc_get(ip);
1602                 if (al == NULL)
1603                         goto out_i;
1604                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1605                                        &data_blocks, &ind_blocks);
1606                 blocks = al->al_requested = 1 + data_blocks + ind_blocks;
1607                 error = gfs2_inplace_reserve(ip);
1608                 if (error)
1609                         goto out_alloc;
1610                 blocks += gfs2_rg_blocks(al);
1611         }
1612
1613         /* Some quotas span block boundaries and can update two blocks,
1614            adding an extra block to the transaction to handle such quotas */
1615         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1616         if (error)
1617                 goto out_release;
1618
1619         /* Apply changes */
1620         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1621
1622         gfs2_trans_end(sdp);
1623 out_release:
1624         if (alloc_required) {
1625                 gfs2_inplace_release(ip);
1626 out_alloc:
1627                 gfs2_alloc_put(ip);
1628         }
1629 out_i:
1630         gfs2_glock_dq_uninit(&i_gh);
1631 out_q:
1632         gfs2_glock_dq_uninit(&q_gh);
1633 out_put:
1634         mutex_unlock(&ip->i_inode.i_mutex);
1635         qd_put(qd);
1636         return error;
1637 }
1638
1639 const struct quotactl_ops gfs2_quotactl_ops = {
1640         .quota_sync     = gfs2_quota_sync,
1641         .get_xstate     = gfs2_quota_get_xstate,
1642         .get_dqblk      = gfs2_get_dqblk,
1643         .set_dqblk      = gfs2_set_dqblk,
1644 };