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   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 to 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/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/lm_interface.h>
  49 #include <linux/kthread.h>
  50 #include <linux/freezer.h>
  51
  52 #include "gfs2.h"
  53 #include "incore.h"
  54 #include "bmap.h"
  55 #include "glock.h"
  56 #include "glops.h"
  57 #include "log.h"
  58 #include "meta_io.h"
  59 #include "quota.h"
  60 #include "rgrp.h"
  61 #include "super.h"
  62 #include "trans.h"
  63 #include "inode.h"
  64 #include "ops_address.h"
  65 #include "util.h"
  66
  67 #define QUOTA_USER 1
  68 #define QUOTA_GROUP 0
  69
  70 struct gfs2_quota_host {
  71         u64 qu_limit;
  72         u64 qu_warn;
  73         s64 qu_value;
  74         u32 qu_ll_next;
  75 };
  76
  77 struct gfs2_quota_change_host {
  78         u64 qc_change;
  79         u32 qc_flags; /* GFS2_QCF_... */
  80         u32 qc_id;
  81 };
  82
  83 static u64 qd2offset(struct gfs2_quota_data *qd)
  84 {
  85         u64 offset;
  86
  87         offset = 2 * (u64)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
  88         offset *= sizeof(struct gfs2_quota);
  89
  90         return offset;
  91 }
  92
  93 static int qd_alloc(struct gfs2_sbd *sdp, int user, u32 id,
  94                     struct gfs2_quota_data **qdp)
  95 {
  96         struct gfs2_quota_data *qd;
  97         int error;
  98
  99         qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
 100         if (!qd)
 101                 return -ENOMEM;
 102
 103         qd->qd_count = 1;
 104         qd->qd_id = id;
 105         if (user)
 106                 set_bit(QDF_USER, &qd->qd_flags);
 107         qd->qd_slot = -1;
 108
 109         error = gfs2_glock_get(sdp, 2 * (u64)id + !user,
 110                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
 111         if (error)
 112                 goto fail;
 113
 114         error = gfs2_lvb_hold(qd->qd_gl);
 115         gfs2_glock_put(qd->qd_gl);
 116         if (error)
 117                 goto fail;
 118
 119         *qdp = qd;
 120
 121         return 0;
 122
 123 fail:
 124         kmem_cache_free(gfs2_quotad_cachep, qd);
 125         return error;
 126 }
 127
 128 static int qd_get(struct gfs2_sbd *sdp, int user, u32 id, int create,
 129                   struct gfs2_quota_data **qdp)
 130 {
 131         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
 132         int error, found;
 133
 134         *qdp = NULL;
 135
 136         for (;;) {
 137                 found = 0;
 138                 spin_lock(&sdp->sd_quota_spin);
 139                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 140                         if (qd->qd_id == id &&
 141                             !test_bit(QDF_USER, &qd->qd_flags) == !user) {
 142                                 qd->qd_count++;
 143                                 found = 1;
 144                                 break;
 145                         }
 146                 }
 147
 148                 if (!found)
 149                         qd = NULL;
 150
 151                 if (!qd && new_qd) {
 152                         qd = new_qd;
 153                         list_add(&qd->qd_list, &sdp->sd_quota_list);
 154                         atomic_inc(&sdp->sd_quota_count);
 155                         new_qd = NULL;
 156                 }
 157
 158                 spin_unlock(&sdp->sd_quota_spin);
 159
 160                 if (qd || !create) {
 161                         if (new_qd) {
 162                                 gfs2_lvb_unhold(new_qd->qd_gl);
 163                                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
 164                         }
 165                         *qdp = qd;
 166                         return 0;
 167                 }
 168
 169                 error = qd_alloc(sdp, user, id, &new_qd);
 170                 if (error)
 171                         return error;
 172         }
 173 }
 174
 175 static void qd_hold(struct gfs2_quota_data *qd)
 176 {
 177         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 178
 179         spin_lock(&sdp->sd_quota_spin);
 180         gfs2_assert(sdp, qd->qd_count);
 181         qd->qd_count++;
 182         spin_unlock(&sdp->sd_quota_spin);
 183 }
 184
 185 static void qd_put(struct gfs2_quota_data *qd)
 186 {
 187         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 188         spin_lock(&sdp->sd_quota_spin);
 189         gfs2_assert(sdp, qd->qd_count);
 190         if (!--qd->qd_count)
 191                 qd->qd_last_touched = jiffies;
 192         spin_unlock(&sdp->sd_quota_spin);
 193 }
 194
 195 static int slot_get(struct gfs2_quota_data *qd)
 196 {
 197         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 198         unsigned int c, o = 0, b;
 199         unsigned char byte = 0;
 200
 201         spin_lock(&sdp->sd_quota_spin);
 202
 203         if (qd->qd_slot_count++) {
 204                 spin_unlock(&sdp->sd_quota_spin);
 205                 return 0;
 206         }
 207
 208         for (c = 0; c < sdp->sd_quota_chunks; c++)
 209                 for (o = 0; o < PAGE_SIZE; o++) {
 210                         byte = sdp->sd_quota_bitmap[c][o];
 211                         if (byte != 0xFF)
 212                                 goto found;
 213                 }
 214
 215         goto fail;
 216
 217 found:
 218         for (b = 0; b < 8; b++)
 219                 if (!(byte & (1 << b)))
 220                         break;
 221         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
 222
 223         if (qd->qd_slot >= sdp->sd_quota_slots)
 224                 goto fail;
 225
 226         sdp->sd_quota_bitmap[c][o] |= 1 << b;
 227
 228         spin_unlock(&sdp->sd_quota_spin);
 229
 230         return 0;
 231
 232 fail:
 233         qd->qd_slot_count--;
 234         spin_unlock(&sdp->sd_quota_spin);
 235         return -ENOSPC;
 236 }
 237
 238 static void slot_hold(struct gfs2_quota_data *qd)
 239 {
 240         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 241
 242         spin_lock(&sdp->sd_quota_spin);
 243         gfs2_assert(sdp, qd->qd_slot_count);
 244         qd->qd_slot_count++;
 245         spin_unlock(&sdp->sd_quota_spin);
 246 }
 247
 248 static void slot_put(struct gfs2_quota_data *qd)
 249 {
 250         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 251
 252         spin_lock(&sdp->sd_quota_spin);
 253         gfs2_assert(sdp, qd->qd_slot_count);
 254         if (!--qd->qd_slot_count) {
 255                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
 256                 qd->qd_slot = -1;
 257         }
 258         spin_unlock(&sdp->sd_quota_spin);
 259 }
 260
 261 static int bh_get(struct gfs2_quota_data *qd)
 262 {
 263         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 264         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 265         unsigned int block, offset;
 266         struct buffer_head *bh;
 267         int error;
 268         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
 269
 270         mutex_lock(&sdp->sd_quota_mutex);
 271
 272         if (qd->qd_bh_count++) {
 273                 mutex_unlock(&sdp->sd_quota_mutex);
 274                 return 0;
 275         }
 276
 277         block = qd->qd_slot / sdp->sd_qc_per_block;
 278         offset = qd->qd_slot % sdp->sd_qc_per_block;
 279
 280         bh_map.b_size = 1 << ip->i_inode.i_blkbits;
 281         error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
 282         if (error)
 283                 goto fail;
 284         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
 285         if (error)
 286                 goto fail;
 287         error = -EIO;
 288         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
 289                 goto fail_brelse;
 290
 291         qd->qd_bh = bh;
 292         qd->qd_bh_qc = (struct gfs2_quota_change *)
 293                 (bh->b_data + sizeof(struct gfs2_meta_header) +
 294                  offset * sizeof(struct gfs2_quota_change));
 295
 296         mutex_unlock(&sdp->sd_quota_mutex);
 297
 298         return 0;
 299
 300 fail_brelse:
 301         brelse(bh);
 302 fail:
 303         qd->qd_bh_count--;
 304         mutex_unlock(&sdp->sd_quota_mutex);
 305         return error;
 306 }
 307
 308 static void bh_put(struct gfs2_quota_data *qd)
 309 {
 310         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 311
 312         mutex_lock(&sdp->sd_quota_mutex);
 313         gfs2_assert(sdp, qd->qd_bh_count);
 314         if (!--qd->qd_bh_count) {
 315                 brelse(qd->qd_bh);
 316                 qd->qd_bh = NULL;
 317                 qd->qd_bh_qc = NULL;
 318         }
 319         mutex_unlock(&sdp->sd_quota_mutex);
 320 }
 321
 322 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
 323 {
 324         struct gfs2_quota_data *qd = NULL;
 325         int error;
 326         int found = 0;
 327
 328         *qdp = NULL;
 329
 330         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 331                 return 0;
 332
 333         spin_lock(&sdp->sd_quota_spin);
 334
 335         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 336                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 337                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
 338                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
 339                         continue;
 340
 341                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 342
 343                 set_bit(QDF_LOCKED, &qd->qd_flags);
 344                 gfs2_assert_warn(sdp, qd->qd_count);
 345                 qd->qd_count++;
 346                 qd->qd_change_sync = qd->qd_change;
 347                 gfs2_assert_warn(sdp, qd->qd_slot_count);
 348                 qd->qd_slot_count++;
 349                 found = 1;
 350
 351                 break;
 352         }
 353
 354         if (!found)
 355                 qd = NULL;
 356
 357         spin_unlock(&sdp->sd_quota_spin);
 358
 359         if (qd) {
 360                 gfs2_assert_warn(sdp, qd->qd_change_sync);
 361                 error = bh_get(qd);
 362                 if (error) {
 363                         clear_bit(QDF_LOCKED, &qd->qd_flags);
 364                         slot_put(qd);
 365                         qd_put(qd);
 366                         return error;
 367                 }
 368         }
 369
 370         *qdp = qd;
 371
 372         return 0;
 373 }
 374
 375 static int qd_trylock(struct gfs2_quota_data *qd)
 376 {
 377         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 378
 379         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 380                 return 0;
 381
 382         spin_lock(&sdp->sd_quota_spin);
 383
 384         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 385             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
 386                 spin_unlock(&sdp->sd_quota_spin);
 387                 return 0;
 388         }
 389
 390         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 391
 392         set_bit(QDF_LOCKED, &qd->qd_flags);
 393         gfs2_assert_warn(sdp, qd->qd_count);
 394         qd->qd_count++;
 395         qd->qd_change_sync = qd->qd_change;
 396         gfs2_assert_warn(sdp, qd->qd_slot_count);
 397         qd->qd_slot_count++;
 398
 399         spin_unlock(&sdp->sd_quota_spin);
 400
 401         gfs2_assert_warn(sdp, qd->qd_change_sync);
 402         if (bh_get(qd)) {
 403                 clear_bit(QDF_LOCKED, &qd->qd_flags);
 404                 slot_put(qd);
 405                 qd_put(qd);
 406                 return 0;
 407         }
 408
 409         return 1;
 410 }
 411
 412 static void qd_unlock(struct gfs2_quota_data *qd)
 413 {
 414         gfs2_assert_warn(qd->qd_gl->gl_sbd,
 415                          test_bit(QDF_LOCKED, &qd->qd_flags));
 416         clear_bit(QDF_LOCKED, &qd->qd_flags);
 417         bh_put(qd);
 418         slot_put(qd);
 419         qd_put(qd);
 420 }
 421
 422 static int qdsb_get(struct gfs2_sbd *sdp, int user, u32 id, int create,
 423                     struct gfs2_quota_data **qdp)
 424 {
 425         int error;
 426
 427         error = qd_get(sdp, user, id, create, qdp);
 428         if (error)
 429                 return error;
 430
 431         error = slot_get(*qdp);
 432         if (error)
 433                 goto fail;
 434
 435         error = bh_get(*qdp);
 436         if (error)
 437                 goto fail_slot;
 438
 439         return 0;
 440
 441 fail_slot:
 442         slot_put(*qdp);
 443 fail:
 444         qd_put(*qdp);
 445         return error;
 446 }
 447
 448 static void qdsb_put(struct gfs2_quota_data *qd)
 449 {
 450         bh_put(qd);
 451         slot_put(qd);
 452         qd_put(qd);
 453 }
 454
 455 int gfs2_quota_hold(struct gfs2_inode *ip, u32 uid, u32 gid)
 456 {
 457         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 458         struct gfs2_alloc *al = ip->i_alloc;
 459         struct gfs2_quota_data **qd = al->al_qd;
 460         int error;
 461
 462         if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
 463             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
 464                 return -EIO;
 465
 466         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 467                 return 0;
 468
 469         error = qdsb_get(sdp, QUOTA_USER, ip->i_inode.i_uid, CREATE, qd);
 470         if (error)
 471                 goto out;
 472         al->al_qd_num++;
 473         qd++;
 474
 475         error = qdsb_get(sdp, QUOTA_GROUP, ip->i_inode.i_gid, CREATE, qd);
 476         if (error)
 477                 goto out;
 478         al->al_qd_num++;
 479         qd++;
 480
 481         if (uid != NO_QUOTA_CHANGE && uid != ip->i_inode.i_uid) {
 482                 error = qdsb_get(sdp, QUOTA_USER, uid, CREATE, qd);
 483                 if (error)
 484                         goto out;
 485                 al->al_qd_num++;
 486                 qd++;
 487         }
 488
 489         if (gid != NO_QUOTA_CHANGE && gid != ip->i_inode.i_gid) {
 490                 error = qdsb_get(sdp, QUOTA_GROUP, gid, CREATE, qd);
 491                 if (error)
 492                         goto out;
 493                 al->al_qd_num++;
 494                 qd++;
 495         }
 496
 497 out:
 498         if (error)
 499                 gfs2_quota_unhold(ip);
 500         return error;
 501 }
 502
 503 void gfs2_quota_unhold(struct gfs2_inode *ip)
 504 {
 505         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 506         struct gfs2_alloc *al = ip->i_alloc;
 507         unsigned int x;
 508
 509         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 510
 511         for (x = 0; x < al->al_qd_num; x++) {
 512                 qdsb_put(al->al_qd[x]);
 513                 al->al_qd[x] = NULL;
 514         }
 515         al->al_qd_num = 0;
 516 }
 517
 518 static int sort_qd(const void *a, const void *b)
 519 {
 520         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
 521         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
 522
 523         if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
 524             !test_bit(QDF_USER, &qd_b->qd_flags)) {
 525                 if (test_bit(QDF_USER, &qd_a->qd_flags))
 526                         return -1;
 527                 else
 528                         return 1;
 529         }
 530         if (qd_a->qd_id < qd_b->qd_id)
 531                 return -1;
 532         if (qd_a->qd_id > qd_b->qd_id)
 533                 return 1;
 534
 535         return 0;
 536 }
 537
 538 static void do_qc(struct gfs2_quota_data *qd, s64 change)
 539 {
 540         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 541         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 542         struct gfs2_quota_change *qc = qd->qd_bh_qc;
 543         s64 x;
 544
 545         mutex_lock(&sdp->sd_quota_mutex);
 546         gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
 547
 548         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
 549                 qc->qc_change = 0;
 550                 qc->qc_flags = 0;
 551                 if (test_bit(QDF_USER, &qd->qd_flags))
 552                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
 553                 qc->qc_id = cpu_to_be32(qd->qd_id);
 554         }
 555
 556         x = be64_to_cpu(qc->qc_change) + change;
 557         qc->qc_change = cpu_to_be64(x);
 558
 559         spin_lock(&sdp->sd_quota_spin);
 560         qd->qd_change = x;
 561         spin_unlock(&sdp->sd_quota_spin);
 562
 563         if (!x) {
 564                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
 565                 clear_bit(QDF_CHANGE, &qd->qd_flags);
 566                 qc->qc_flags = 0;
 567                 qc->qc_id = 0;
 568                 slot_put(qd);
 569                 qd_put(qd);
 570         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
 571                 qd_hold(qd);
 572                 slot_hold(qd);
 573         }
 574
 575         mutex_unlock(&sdp->sd_quota_mutex);
 576 }
 577
 578 static void gfs2_quota_in(struct gfs2_quota_host *qu, const void *buf)
 579 {
 580         const struct gfs2_quota *str = buf;
 581
 582         qu->qu_limit = be64_to_cpu(str->qu_limit);
 583         qu->qu_warn = be64_to_cpu(str->qu_warn);
 584         qu->qu_value = be64_to_cpu(str->qu_value);
 585         qu->qu_ll_next = be32_to_cpu(str->qu_ll_next);
 586 }
 587
 588 static void gfs2_quota_out(const struct gfs2_quota_host *qu, void *buf)
 589 {
 590         struct gfs2_quota *str = buf;
 591
 592         str->qu_limit = cpu_to_be64(qu->qu_limit);
 593         str->qu_warn = cpu_to_be64(qu->qu_warn);
 594         str->qu_value = cpu_to_be64(qu->qu_value);
 595         str->qu_ll_next = cpu_to_be32(qu->qu_ll_next);
 596         memset(&str->qu_reserved, 0, sizeof(str->qu_reserved));
 597 }
 598
 599 /**
 600  * gfs2_adjust_quota
 601  *
 602  * This function was mostly borrowed from gfs2_block_truncate_page which was
 603  * in turn mostly borrowed from ext3
 604  */
 605 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 606                              s64 change, struct gfs2_quota_data *qd)
 607 {
 608         struct inode *inode = &ip->i_inode;
 609         struct address_space *mapping = inode->i_mapping;
 610         unsigned long index = loc >> PAGE_CACHE_SHIFT;
 611         unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
 612         unsigned blocksize, iblock, pos;
 613         struct buffer_head *bh;
 614         struct page *page;
 615         void *kaddr;
 616         char *ptr;
 617         struct gfs2_quota_host qp;
 618         s64 value;
 619         int err = -EIO;
 620
 621         if (gfs2_is_stuffed(ip))
 622                 gfs2_unstuff_dinode(ip, NULL);
 623
 624         page = grab_cache_page(mapping, index);
 625         if (!page)
 626                 return -ENOMEM;
 627
 628         blocksize = inode->i_sb->s_blocksize;
 629         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
 630
 631         if (!page_has_buffers(page))
 632                 create_empty_buffers(page, blocksize, 0);
 633
 634         bh = page_buffers(page);
 635         pos = blocksize;
 636         while (offset >= pos) {
 637                 bh = bh->b_this_page;
 638                 iblock++;
 639                 pos += blocksize;
 640         }
 641
 642         if (!buffer_mapped(bh)) {
 643                 gfs2_block_map(inode, iblock, bh, 1);
 644                 if (!buffer_mapped(bh))
 645                         goto unlock;
 646         }
 647
 648         if (PageUptodate(page))
 649                 set_buffer_uptodate(bh);
 650
 651         if (!buffer_uptodate(bh)) {
 652                 ll_rw_block(READ_META, 1, &bh);
 653                 wait_on_buffer(bh);
 654                 if (!buffer_uptodate(bh))
 655                         goto unlock;
 656         }
 657
 658         gfs2_trans_add_bh(ip->i_gl, bh, 0);
 659
 660         kaddr = kmap_atomic(page, KM_USER0);
 661         ptr = kaddr + offset;
 662         gfs2_quota_in(&qp, ptr);
 663         qp.qu_value += change;
 664         value = qp.qu_value;
 665         gfs2_quota_out(&qp, ptr);
 666         flush_dcache_page(page);
 667         kunmap_atomic(kaddr, KM_USER0);
 668         err = 0;
 669         qd->qd_qb.qb_magic = cpu_to_be32(GFS2_MAGIC);
 670         qd->qd_qb.qb_value = cpu_to_be64(value);
 671         ((struct gfs2_quota_lvb*)(qd->qd_gl->gl_lvb))->qb_magic = cpu_to_be32(GFS2_MAGIC);
 672         ((struct gfs2_quota_lvb*)(qd->qd_gl->gl_lvb))->qb_value = cpu_to_be64(value);
 673 unlock:
 674         unlock_page(page);
 675         page_cache_release(page);
 676         return err;
 677 }
 678
 679 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 680 {
 681         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
 682         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 683         unsigned int data_blocks, ind_blocks;
 684         struct gfs2_holder *ghs, i_gh;
 685         unsigned int qx, x;
 686         struct gfs2_quota_data *qd;
 687         loff_t offset;
 688         unsigned int nalloc = 0, blocks;
 689         struct gfs2_alloc *al = NULL;
 690         int error;
 691
 692         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 693                               &data_blocks, &ind_blocks);
 694
 695         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
 696         if (!ghs)
 697                 return -ENOMEM;
 698
 699         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 700         for (qx = 0; qx < num_qd; qx++) {
 701                 error = gfs2_glock_nq_init(qda[qx]->qd_gl,
 702                                            LM_ST_EXCLUSIVE,
 703                                            GL_NOCACHE, &ghs[qx]);
 704                 if (error)
 705                         goto out;
 706         }
 707
 708         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 709         if (error)
 710                 goto out;
 711
 712         for (x = 0; x < num_qd; x++) {
 713                 int alloc_required;
 714
 715                 offset = qd2offset(qda[x]);
 716                 error = gfs2_write_alloc_required(ip, offset,
 717                                                   sizeof(struct gfs2_quota),
 718                                                   &alloc_required);
 719                 if (error)
 720                         goto out_gunlock;
 721                 if (alloc_required)
 722                         nalloc++;
 723         }
 724
 725         al = gfs2_alloc_get(ip);
 726         if (!al) {
 727                 error = -ENOMEM;
 728                 goto out_gunlock;
 729         }
 730         /*
 731          * 1 blk for unstuffing inode if stuffed. We add this extra
 732          * block to the reservation unconditionally. If the inode
 733          * doesn't need unstuffing, the block will be released to the
 734          * rgrp since it won't be allocated during the transaction
 735          */
 736         al->al_requested = 1;
 737         /* +1 in the end for block requested above for unstuffing */
 738         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 1;
 739
 740         if (nalloc)
 741                 al->al_requested += nalloc * (data_blocks + ind_blocks);
 742         error = gfs2_inplace_reserve(ip);
 743         if (error)
 744                 goto out_alloc;
 745
 746         if (nalloc)
 747                 blocks += al->al_rgd->rd_length + nalloc * ind_blocks + RES_STATFS;
 748
 749         error = gfs2_trans_begin(sdp, blocks, 0);
 750         if (error)
 751                 goto out_ipres;
 752
 753         for (x = 0; x < num_qd; x++) {
 754                 qd = qda[x];
 755                 offset = qd2offset(qd);
 756                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync,
 757                                           (struct gfs2_quota_data *)
 758                                           qd);
 759                 if (error)
 760                         goto out_end_trans;
 761
 762                 do_qc(qd, -qd->qd_change_sync);
 763         }
 764
 765         error = 0;
 766
 767 out_end_trans:
 768         gfs2_trans_end(sdp);
 769 out_ipres:
 770         gfs2_inplace_release(ip);
 771 out_alloc:
 772         gfs2_alloc_put(ip);
 773 out_gunlock:
 774         gfs2_glock_dq_uninit(&i_gh);
 775 out:
 776         while (qx--)
 777                 gfs2_glock_dq_uninit(&ghs[qx]);
 778         kfree(ghs);
 779         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
 780         return error;
 781 }
 782
 783 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 784                     struct gfs2_holder *q_gh)
 785 {
 786         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 787         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 788         struct gfs2_holder i_gh;
 789         struct gfs2_quota_host q;
 790         char buf[sizeof(struct gfs2_quota)];
 791         int error;
 792         struct gfs2_quota_lvb *qlvb;
 793
 794 restart:
 795         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 796         if (error)
 797                 return error;
 798
 799         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 800
 801         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
 802                 loff_t pos;
 803                 gfs2_glock_dq_uninit(q_gh);
 804                 error = gfs2_glock_nq_init(qd->qd_gl,
 805                                           LM_ST_EXCLUSIVE, GL_NOCACHE,
 806                                           q_gh);
 807                 if (error)
 808                         return error;
 809
 810                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
 811                 if (error)
 812                         goto fail;
 813
 814                 memset(buf, 0, sizeof(struct gfs2_quota));
 815                 pos = qd2offset(qd);
 816                 error = gfs2_internal_read(ip, NULL, buf, &pos,
 817                                            sizeof(struct gfs2_quota));
 818                 if (error < 0)
 819                         goto fail_gunlock;
 820
 821                 gfs2_glock_dq_uninit(&i_gh);
 822
 823
 824                 gfs2_quota_in(&q, buf);
 825                 qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 826                 qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
 827                 qlvb->__pad = 0;
 828                 qlvb->qb_limit = cpu_to_be64(q.qu_limit);
 829                 qlvb->qb_warn = cpu_to_be64(q.qu_warn);
 830                 qlvb->qb_value = cpu_to_be64(q.qu_value);
 831                 qd->qd_qb = *qlvb;
 832
 833                 if (gfs2_glock_is_blocking(qd->qd_gl)) {
 834                         gfs2_glock_dq_uninit(q_gh);
 835                         force_refresh = 0;
 836                         goto restart;
 837                 }
 838         }
 839
 840         return 0;
 841
 842 fail_gunlock:
 843         gfs2_glock_dq_uninit(&i_gh);
 844 fail:
 845         gfs2_glock_dq_uninit(q_gh);
 846         return error;
 847 }
 848
 849 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
 850 {
 851         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 852         struct gfs2_alloc *al = ip->i_alloc;
 853         unsigned int x;
 854         int error = 0;
 855
 856         gfs2_quota_hold(ip, uid, gid);
 857
 858         if (capable(CAP_SYS_RESOURCE) ||
 859             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 860                 return 0;
 861
 862         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
 863              sort_qd, NULL);
 864
 865         for (x = 0; x < al->al_qd_num; x++) {
 866                 error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
 867                 if (error)
 868                         break;
 869         }
 870
 871         if (!error)
 872                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
 873         else {
 874                 while (x--)
 875                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 876                 gfs2_quota_unhold(ip);
 877         }
 878
 879         return error;
 880 }
 881
 882 static int need_sync(struct gfs2_quota_data *qd)
 883 {
 884         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 885         struct gfs2_tune *gt = &sdp->sd_tune;
 886         s64 value;
 887         unsigned int num, den;
 888         int do_sync = 1;
 889
 890         if (!qd->qd_qb.qb_limit)
 891                 return 0;
 892
 893         spin_lock(&sdp->sd_quota_spin);
 894         value = qd->qd_change;
 895         spin_unlock(&sdp->sd_quota_spin);
 896
 897         spin_lock(&gt->gt_spin);
 898         num = gt->gt_quota_scale_num;
 899         den = gt->gt_quota_scale_den;
 900         spin_unlock(&gt->gt_spin);
 901
 902         if (value < 0)
 903                 do_sync = 0;
 904         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
 905                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 906                 do_sync = 0;
 907         else {
 908                 value *= gfs2_jindex_size(sdp) * num;
 909                 value = div_s64(value, den);
 910                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
 911                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 912                         do_sync = 0;
 913         }
 914
 915         return do_sync;
 916 }
 917
 918 void gfs2_quota_unlock(struct gfs2_inode *ip)
 919 {
 920         struct gfs2_alloc *al = ip->i_alloc;
 921         struct gfs2_quota_data *qda[4];
 922         unsigned int count = 0;
 923         unsigned int x;
 924
 925         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
 926                 goto out;
 927
 928         for (x = 0; x < al->al_qd_num; x++) {
 929                 struct gfs2_quota_data *qd;
 930                 int sync;
 931
 932                 qd = al->al_qd[x];
 933                 sync = need_sync(qd);
 934
 935                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 936
 937                 if (sync && qd_trylock(qd))
 938                         qda[count++] = qd;
 939         }
 940
 941         if (count) {
 942                 do_sync(count, qda);
 943                 for (x = 0; x < count; x++)
 944                         qd_unlock(qda[x]);
 945         }
 946
 947 out:
 948         gfs2_quota_unhold(ip);
 949 }
 950
 951 #define MAX_LINE 256
 952
 953 static int print_message(struct gfs2_quota_data *qd, char *type)
 954 {
 955         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 956
 957         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\r\n",
 958                sdp->sd_fsname, type,
 959                (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
 960                qd->qd_id);
 961
 962         return 0;
 963 }
 964
 965 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
 966 {
 967         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 968         struct gfs2_alloc *al = ip->i_alloc;
 969         struct gfs2_quota_data *qd;
 970         s64 value;
 971         unsigned int x;
 972         int error = 0;
 973
 974         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
 975                 return 0;
 976
 977         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 978                 return 0;
 979
 980         for (x = 0; x < al->al_qd_num; x++) {
 981                 qd = al->al_qd[x];
 982
 983                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
 984                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
 985                         continue;
 986
 987                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
 988                 spin_lock(&sdp->sd_quota_spin);
 989                 value += qd->qd_change;
 990                 spin_unlock(&sdp->sd_quota_spin);
 991
 992                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
 993                         print_message(qd, "exceeded");
 994                         error = -EDQUOT;
 995                         break;
 996                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
 997                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
 998                            time_after_eq(jiffies, qd->qd_last_warn +
 999                                          gfs2_tune_get(sdp,
1000                                                 gt_quota_warn_period) * HZ)) {
1001                         error = print_message(qd, "warning");
1002                         qd->qd_last_warn = jiffies;
1003                 }
1004         }
1005
1006         return error;
1007 }
1008
1009 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1010                        u32 uid, u32 gid)
1011 {
1012         struct gfs2_alloc *al = ip->i_alloc;
1013         struct gfs2_quota_data *qd;
1014         unsigned int x;
1015
1016         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1017                 return;
1018         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1019                 return;
1020
1021         for (x = 0; x < al->al_qd_num; x++) {
1022                 qd = al->al_qd[x];
1023
1024                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1025                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
1026                         do_qc(qd, change);
1027                 }
1028         }
1029 }
1030
1031 int gfs2_quota_sync(struct gfs2_sbd *sdp)
1032 {
1033         struct gfs2_quota_data **qda;
1034         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1035         unsigned int num_qd;
1036         unsigned int x;
1037         int error = 0;
1038
1039         sdp->sd_quota_sync_gen++;
1040
1041         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1042         if (!qda)
1043                 return -ENOMEM;
1044
1045         do {
1046                 num_qd = 0;
1047
1048                 for (;;) {
1049                         error = qd_fish(sdp, qda + num_qd);
1050                         if (error || !qda[num_qd])
1051                                 break;
1052                         if (++num_qd == max_qd)
1053                                 break;
1054                 }
1055
1056                 if (num_qd) {
1057                         if (!error)
1058                                 error = do_sync(num_qd, qda);
1059                         if (!error)
1060                                 for (x = 0; x < num_qd; x++)
1061                                         qda[x]->qd_sync_gen =
1062                                                 sdp->sd_quota_sync_gen;
1063
1064                         for (x = 0; x < num_qd; x++)
1065                                 qd_unlock(qda[x]);
1066                 }
1067         } while (!error && num_qd == max_qd);
1068
1069         kfree(qda);
1070
1071         return error;
1072 }
1073
1074 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1075 {
1076         struct gfs2_quota_data *qd;
1077         struct gfs2_holder q_gh;
1078         int error;
1079
1080         error = qd_get(sdp, user, id, CREATE, &qd);
1081         if (error)
1082                 return error;
1083
1084         error = do_glock(qd, FORCE, &q_gh);
1085         if (!error)
1086                 gfs2_glock_dq_uninit(&q_gh);
1087
1088         qd_put(qd);
1089
1090         return error;
1091 }
1092
1093 static void gfs2_quota_change_in(struct gfs2_quota_change_host *qc, const void *buf)
1094 {
1095         const struct gfs2_quota_change *str = buf;
1096
1097         qc->qc_change = be64_to_cpu(str->qc_change);
1098         qc->qc_flags = be32_to_cpu(str->qc_flags);
1099         qc->qc_id = be32_to_cpu(str->qc_id);
1100 }
1101
1102 int gfs2_quota_init(struct gfs2_sbd *sdp)
1103 {
1104         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1105         unsigned int blocks = ip->i_disksize >> sdp->sd_sb.sb_bsize_shift;
1106         unsigned int x, slot = 0;
1107         unsigned int found = 0;
1108         u64 dblock;
1109         u32 extlen = 0;
1110         int error;
1111
1112         if (!ip->i_disksize || ip->i_disksize > (64 << 20) ||
1113             ip->i_disksize & (sdp->sd_sb.sb_bsize - 1)) {
1114                 gfs2_consist_inode(ip);
1115                 return -EIO;
1116         }
1117         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1118         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1119
1120         error = -ENOMEM;
1121
1122         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1123                                        sizeof(unsigned char *), GFP_NOFS);
1124         if (!sdp->sd_quota_bitmap)
1125                 return error;
1126
1127         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1128                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_NOFS);
1129                 if (!sdp->sd_quota_bitmap[x])
1130                         goto fail;
1131         }
1132
1133         for (x = 0; x < blocks; x++) {
1134                 struct buffer_head *bh;
1135                 unsigned int y;
1136
1137                 if (!extlen) {
1138                         int new = 0;
1139                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1140                         if (error)
1141                                 goto fail;
1142                 }
1143                 error = -EIO;
1144                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1145                 if (!bh)
1146                         goto fail;
1147                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1148                         brelse(bh);
1149                         goto fail;
1150                 }
1151
1152                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1153                      y++, slot++) {
1154                         struct gfs2_quota_change_host qc;
1155                         struct gfs2_quota_data *qd;
1156
1157                         gfs2_quota_change_in(&qc, bh->b_data +
1158                                           sizeof(struct gfs2_meta_header) +
1159                                           y * sizeof(struct gfs2_quota_change));
1160                         if (!qc.qc_change)
1161                                 continue;
1162
1163                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1164                                          qc.qc_id, &qd);
1165                         if (error) {
1166                                 brelse(bh);
1167                                 goto fail;
1168                         }
1169
1170                         set_bit(QDF_CHANGE, &qd->qd_flags);
1171                         qd->qd_change = qc.qc_change;
1172                         qd->qd_slot = slot;
1173                         qd->qd_slot_count = 1;
1174                         qd->qd_last_touched = jiffies;
1175
1176                         spin_lock(&sdp->sd_quota_spin);
1177                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1178                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1179                         atomic_inc(&sdp->sd_quota_count);
1180                         spin_unlock(&sdp->sd_quota_spin);
1181
1182                         found++;
1183                 }
1184
1185                 brelse(bh);
1186                 dblock++;
1187                 extlen--;
1188         }
1189
1190         if (found)
1191                 fs_info(sdp, "found %u quota changes\n", found);
1192
1193         return 0;
1194
1195 fail:
1196         gfs2_quota_cleanup(sdp);
1197         return error;
1198 }
1199
1200 static void gfs2_quota_scan(struct gfs2_sbd *sdp)
1201 {
1202         struct gfs2_quota_data *qd, *safe;
1203         LIST_HEAD(dead);
1204
1205         spin_lock(&sdp->sd_quota_spin);
1206         list_for_each_entry_safe(qd, safe, &sdp->sd_quota_list, qd_list) {
1207                 if (!qd->qd_count &&
1208                     time_after_eq(jiffies, qd->qd_last_touched +
1209                                 gfs2_tune_get(sdp, gt_quota_cache_secs) * HZ)) {
1210                         list_move(&qd->qd_list, &dead);
1211                         gfs2_assert_warn(sdp,
1212                                          atomic_read(&sdp->sd_quota_count) > 0);
1213                         atomic_dec(&sdp->sd_quota_count);
1214                 }
1215         }
1216         spin_unlock(&sdp->sd_quota_spin);
1217
1218         while (!list_empty(&dead)) {
1219                 qd = list_entry(dead.next, struct gfs2_quota_data, qd_list);
1220                 list_del(&qd->qd_list);
1221
1222                 gfs2_assert_warn(sdp, !qd->qd_change);
1223                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1224                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1225
1226                 gfs2_lvb_unhold(qd->qd_gl);
1227                 kmem_cache_free(gfs2_quotad_cachep, qd);
1228         }
1229 }
1230
1231 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1232 {
1233         struct list_head *head = &sdp->sd_quota_list;
1234         struct gfs2_quota_data *qd;
1235         unsigned int x;
1236
1237         spin_lock(&sdp->sd_quota_spin);
1238         while (!list_empty(head)) {
1239                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1240
1241                 if (qd->qd_count > 1 ||
1242                     (qd->qd_count && !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1243                         list_move(&qd->qd_list, head);
1244                         spin_unlock(&sdp->sd_quota_spin);
1245                         schedule();
1246                         spin_lock(&sdp->sd_quota_spin);
1247                         continue;
1248                 }
1249
1250                 list_del(&qd->qd_list);
1251                 atomic_dec(&sdp->sd_quota_count);
1252                 spin_unlock(&sdp->sd_quota_spin);
1253
1254                 if (!qd->qd_count) {
1255                         gfs2_assert_warn(sdp, !qd->qd_change);
1256                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1257                 } else
1258                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1259                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1260
1261                 gfs2_lvb_unhold(qd->qd_gl);
1262                 kmem_cache_free(gfs2_quotad_cachep, qd);
1263
1264                 spin_lock(&sdp->sd_quota_spin);
1265         }
1266         spin_unlock(&sdp->sd_quota_spin);
1267
1268         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1269
1270         if (sdp->sd_quota_bitmap) {
1271                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1272                         kfree(sdp->sd_quota_bitmap[x]);
1273                 kfree(sdp->sd_quota_bitmap);
1274         }
1275 }
1276
1277 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1278 {
1279         if (error == 0 || error == -EROFS)
1280                 return;
1281         if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1282                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1283 }
1284
1285 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1286                                int (*fxn)(struct gfs2_sbd *sdp),
1287                                unsigned long t, unsigned long *timeo,
1288                                unsigned int *new_timeo)
1289 {
1290         if (t >= *timeo) {
1291                 int error = fxn(sdp);
1292                 quotad_error(sdp, msg, error);
1293                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1294         } else {
1295                 *timeo -= t;
1296         }
1297 }
1298
1299 /**
1300  * gfs2_quotad - Write cached quota changes into the quota file
1301  * @sdp: Pointer to GFS2 superblock
1302  *
1303  */
1304
1305 int gfs2_quotad(void *data)
1306 {
1307         struct gfs2_sbd *sdp = data;
1308         struct gfs2_tune *tune = &sdp->sd_tune;
1309         unsigned long statfs_timeo = 0;
1310         unsigned long quotad_timeo = 0;
1311         unsigned long t = 0;
1312         DEFINE_WAIT(wait);
1313
1314         while (!kthread_should_stop()) {
1315
1316                 /* Update the master statfs file */
1317                 quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1318                                    &statfs_timeo, &tune->gt_statfs_quantum);
1319
1320                 /* Update quota file */
1321                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1322                                    &quotad_timeo, &tune->gt_quota_quantum);
1323
1324                 /* FIXME: This should be turned into a shrinker */
1325                 gfs2_quota_scan(sdp);
1326
1327                 if (freezing(current))
1328                         refrigerator();
1329                 t = min(quotad_timeo, statfs_timeo);
1330
1331                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_UNINTERRUPTIBLE);
1332                 t -= schedule_timeout(t);
1333                 finish_wait(&sdp->sd_quota_wait, &wait);
1334         }
1335
1336         return 0;
1337 }
1338