SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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/spinlock.h>
  42 #include <linux/completion.h>
  43 #include <linux/buffer_head.h>
  44 #include <linux/sort.h>
  45 #include <linux/fs.h>
  46 #include <linux/bio.h>
  47 #include <linux/gfs2_ondisk.h>
  48 #include <linux/kthread.h>
  49 #include <linux/freezer.h>
  50 #include <linux/dqblk_xfs.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 "util.h"
  65
  66 #define QUOTA_USER 1
  67 #define QUOTA_GROUP 0
  68
  69 struct gfs2_quota_change_host {
  70         u64 qc_change;
  71         u32 qc_flags; /* GFS2_QCF_... */
  72         u32 qc_id;
  73 };
  74
  75 static LIST_HEAD(qd_lru_list);
  76 static atomic_t qd_lru_count = ATOMIC_INIT(0);
  77 static DEFINE_SPINLOCK(qd_lru_lock);
  78
  79 int gfs2_shrink_qd_memory(int nr, gfp_t gfp_mask)
  80 {
  81         struct gfs2_quota_data *qd;
  82         struct gfs2_sbd *sdp;
  83
  84         if (nr == 0)
  85                 goto out;
  86
  87         if (!(gfp_mask & __GFP_FS))
  88                 return -1;
  89
  90         spin_lock(&qd_lru_lock);
  91         while (nr && !list_empty(&qd_lru_list)) {
  92                 qd = list_entry(qd_lru_list.next,
  93                                 struct gfs2_quota_data, qd_reclaim);
  94                 sdp = qd->qd_gl->gl_sbd;
  95
  96                 /* Free from the filesystem-specific list */
  97                 list_del(&qd->qd_list);
  98
  99                 gfs2_assert_warn(sdp, !qd->qd_change);
 100                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
 101                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
 102
 103                 gfs2_glock_put(qd->qd_gl);
 104                 atomic_dec(&sdp->sd_quota_count);
 105
 106                 /* Delete it from the common reclaim list */
 107                 list_del_init(&qd->qd_reclaim);
 108                 atomic_dec(&qd_lru_count);
 109                 spin_unlock(&qd_lru_lock);
 110                 kmem_cache_free(gfs2_quotad_cachep, qd);
 111                 spin_lock(&qd_lru_lock);
 112                 nr--;
 113         }
 114         spin_unlock(&qd_lru_lock);
 115
 116 out:
 117         return (atomic_read(&qd_lru_count) * sysctl_vfs_cache_pressure) / 100;
 118 }
 119
 120 static u64 qd2offset(struct gfs2_quota_data *qd)
 121 {
 122         u64 offset;
 123
 124         offset = 2 * (u64)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
 125         offset *= sizeof(struct gfs2_quota);
 126
 127         return offset;
 128 }
 129
 130 static int qd_alloc(struct gfs2_sbd *sdp, int user, u32 id,
 131                     struct gfs2_quota_data **qdp)
 132 {
 133         struct gfs2_quota_data *qd;
 134         int error;
 135
 136         qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
 137         if (!qd)
 138                 return -ENOMEM;
 139
 140         atomic_set(&qd->qd_count, 1);
 141         qd->qd_id = id;
 142         if (user)
 143                 set_bit(QDF_USER, &qd->qd_flags);
 144         qd->qd_slot = -1;
 145         INIT_LIST_HEAD(&qd->qd_reclaim);
 146
 147         error = gfs2_glock_get(sdp, 2 * (u64)id + !user,
 148                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
 149         if (error)
 150                 goto fail;
 151
 152         *qdp = qd;
 153
 154         return 0;
 155
 156 fail:
 157         kmem_cache_free(gfs2_quotad_cachep, qd);
 158         return error;
 159 }
 160
 161 static int qd_get(struct gfs2_sbd *sdp, int user, u32 id,
 162                   struct gfs2_quota_data **qdp)
 163 {
 164         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
 165         int error, found;
 166
 167         *qdp = NULL;
 168
 169         for (;;) {
 170                 found = 0;
 171                 spin_lock(&qd_lru_lock);
 172                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 173                         if (qd->qd_id == id &&
 174                             !test_bit(QDF_USER, &qd->qd_flags) == !user) {
 175                                 if (!atomic_read(&qd->qd_count) &&
 176                                     !list_empty(&qd->qd_reclaim)) {
 177                                         /* Remove it from reclaim list */
 178                                         list_del_init(&qd->qd_reclaim);
 179                                         atomic_dec(&qd_lru_count);
 180                                 }
 181                                 atomic_inc(&qd->qd_count);
 182                                 found = 1;
 183                                 break;
 184                         }
 185                 }
 186
 187                 if (!found)
 188                         qd = NULL;
 189
 190                 if (!qd && new_qd) {
 191                         qd = new_qd;
 192                         list_add(&qd->qd_list, &sdp->sd_quota_list);
 193                         atomic_inc(&sdp->sd_quota_count);
 194                         new_qd = NULL;
 195                 }
 196
 197                 spin_unlock(&qd_lru_lock);
 198
 199                 if (qd) {
 200                         if (new_qd) {
 201                                 gfs2_glock_put(new_qd->qd_gl);
 202                                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
 203                         }
 204                         *qdp = qd;
 205                         return 0;
 206                 }
 207
 208                 error = qd_alloc(sdp, user, id, &new_qd);
 209                 if (error)
 210                         return error;
 211         }
 212 }
 213
 214 static void qd_hold(struct gfs2_quota_data *qd)
 215 {
 216         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 217         gfs2_assert(sdp, atomic_read(&qd->qd_count));
 218         atomic_inc(&qd->qd_count);
 219 }
 220
 221 static void qd_put(struct gfs2_quota_data *qd)
 222 {
 223         if (atomic_dec_and_lock(&qd->qd_count, &qd_lru_lock)) {
 224                 /* Add to the reclaim list */
 225                 list_add_tail(&qd->qd_reclaim, &qd_lru_list);
 226                 atomic_inc(&qd_lru_count);
 227                 spin_unlock(&qd_lru_lock);
 228         }
 229 }
 230
 231 static int slot_get(struct gfs2_quota_data *qd)
 232 {
 233         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 234         unsigned int c, o = 0, b;
 235         unsigned char byte = 0;
 236
 237         spin_lock(&qd_lru_lock);
 238
 239         if (qd->qd_slot_count++) {
 240                 spin_unlock(&qd_lru_lock);
 241                 return 0;
 242         }
 243
 244         for (c = 0; c < sdp->sd_quota_chunks; c++)
 245                 for (o = 0; o < PAGE_SIZE; o++) {
 246                         byte = sdp->sd_quota_bitmap[c][o];
 247                         if (byte != 0xFF)
 248                                 goto found;
 249                 }
 250
 251         goto fail;
 252
 253 found:
 254         for (b = 0; b < 8; b++)
 255                 if (!(byte & (1 << b)))
 256                         break;
 257         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
 258
 259         if (qd->qd_slot >= sdp->sd_quota_slots)
 260                 goto fail;
 261
 262         sdp->sd_quota_bitmap[c][o] |= 1 << b;
 263
 264         spin_unlock(&qd_lru_lock);
 265
 266         return 0;
 267
 268 fail:
 269         qd->qd_slot_count--;
 270         spin_unlock(&qd_lru_lock);
 271         return -ENOSPC;
 272 }
 273
 274 static void slot_hold(struct gfs2_quota_data *qd)
 275 {
 276         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 277
 278         spin_lock(&qd_lru_lock);
 279         gfs2_assert(sdp, qd->qd_slot_count);
 280         qd->qd_slot_count++;
 281         spin_unlock(&qd_lru_lock);
 282 }
 283
 284 static void slot_put(struct gfs2_quota_data *qd)
 285 {
 286         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 287
 288         spin_lock(&qd_lru_lock);
 289         gfs2_assert(sdp, qd->qd_slot_count);
 290         if (!--qd->qd_slot_count) {
 291                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
 292                 qd->qd_slot = -1;
 293         }
 294         spin_unlock(&qd_lru_lock);
 295 }
 296
 297 static int bh_get(struct gfs2_quota_data *qd)
 298 {
 299         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 300         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 301         unsigned int block, offset;
 302         struct buffer_head *bh;
 303         int error;
 304         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
 305
 306         mutex_lock(&sdp->sd_quota_mutex);
 307
 308         if (qd->qd_bh_count++) {
 309                 mutex_unlock(&sdp->sd_quota_mutex);
 310                 return 0;
 311         }
 312
 313         block = qd->qd_slot / sdp->sd_qc_per_block;
 314         offset = qd->qd_slot % sdp->sd_qc_per_block;
 315
 316         bh_map.b_size = 1 << ip->i_inode.i_blkbits;
 317         error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
 318         if (error)
 319                 goto fail;
 320         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
 321         if (error)
 322                 goto fail;
 323         error = -EIO;
 324         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
 325                 goto fail_brelse;
 326
 327         qd->qd_bh = bh;
 328         qd->qd_bh_qc = (struct gfs2_quota_change *)
 329                 (bh->b_data + sizeof(struct gfs2_meta_header) +
 330                  offset * sizeof(struct gfs2_quota_change));
 331
 332         mutex_unlock(&sdp->sd_quota_mutex);
 333
 334         return 0;
 335
 336 fail_brelse:
 337         brelse(bh);
 338 fail:
 339         qd->qd_bh_count--;
 340         mutex_unlock(&sdp->sd_quota_mutex);
 341         return error;
 342 }
 343
 344 static void bh_put(struct gfs2_quota_data *qd)
 345 {
 346         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 347
 348         mutex_lock(&sdp->sd_quota_mutex);
 349         gfs2_assert(sdp, qd->qd_bh_count);
 350         if (!--qd->qd_bh_count) {
 351                 brelse(qd->qd_bh);
 352                 qd->qd_bh = NULL;
 353                 qd->qd_bh_qc = NULL;
 354         }
 355         mutex_unlock(&sdp->sd_quota_mutex);
 356 }
 357
 358 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
 359 {
 360         struct gfs2_quota_data *qd = NULL;
 361         int error;
 362         int found = 0;
 363
 364         *qdp = NULL;
 365
 366         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 367                 return 0;
 368
 369         spin_lock(&qd_lru_lock);
 370
 371         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 372                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 373                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
 374                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
 375                         continue;
 376
 377                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 378
 379                 set_bit(QDF_LOCKED, &qd->qd_flags);
 380                 gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
 381                 atomic_inc(&qd->qd_count);
 382                 qd->qd_change_sync = qd->qd_change;
 383                 gfs2_assert_warn(sdp, qd->qd_slot_count);
 384                 qd->qd_slot_count++;
 385                 found = 1;
 386
 387                 break;
 388         }
 389
 390         if (!found)
 391                 qd = NULL;
 392
 393         spin_unlock(&qd_lru_lock);
 394
 395         if (qd) {
 396                 gfs2_assert_warn(sdp, qd->qd_change_sync);
 397                 error = bh_get(qd);
 398                 if (error) {
 399                         clear_bit(QDF_LOCKED, &qd->qd_flags);
 400                         slot_put(qd);
 401                         qd_put(qd);
 402                         return error;
 403                 }
 404         }
 405
 406         *qdp = qd;
 407
 408         return 0;
 409 }
 410
 411 static int qd_trylock(struct gfs2_quota_data *qd)
 412 {
 413         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 414
 415         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 416                 return 0;
 417
 418         spin_lock(&qd_lru_lock);
 419
 420         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 421             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
 422                 spin_unlock(&qd_lru_lock);
 423                 return 0;
 424         }
 425
 426         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 427
 428         set_bit(QDF_LOCKED, &qd->qd_flags);
 429         gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
 430         atomic_inc(&qd->qd_count);
 431         qd->qd_change_sync = qd->qd_change;
 432         gfs2_assert_warn(sdp, qd->qd_slot_count);
 433         qd->qd_slot_count++;
 434
 435         spin_unlock(&qd_lru_lock);
 436
 437         gfs2_assert_warn(sdp, qd->qd_change_sync);
 438         if (bh_get(qd)) {
 439                 clear_bit(QDF_LOCKED, &qd->qd_flags);
 440                 slot_put(qd);
 441                 qd_put(qd);
 442                 return 0;
 443         }
 444
 445         return 1;
 446 }
 447
 448 static void qd_unlock(struct gfs2_quota_data *qd)
 449 {
 450         gfs2_assert_warn(qd->qd_gl->gl_sbd,
 451                          test_bit(QDF_LOCKED, &qd->qd_flags));
 452         clear_bit(QDF_LOCKED, &qd->qd_flags);
 453         bh_put(qd);
 454         slot_put(qd);
 455         qd_put(qd);
 456 }
 457
 458 static int qdsb_get(struct gfs2_sbd *sdp, int user, u32 id,
 459                     struct gfs2_quota_data **qdp)
 460 {
 461         int error;
 462
 463         error = qd_get(sdp, user, id, qdp);
 464         if (error)
 465                 return error;
 466
 467         error = slot_get(*qdp);
 468         if (error)
 469                 goto fail;
 470
 471         error = bh_get(*qdp);
 472         if (error)
 473                 goto fail_slot;
 474
 475         return 0;
 476
 477 fail_slot:
 478         slot_put(*qdp);
 479 fail:
 480         qd_put(*qdp);
 481         return error;
 482 }
 483
 484 static void qdsb_put(struct gfs2_quota_data *qd)
 485 {
 486         bh_put(qd);
 487         slot_put(qd);
 488         qd_put(qd);
 489 }
 490
 491 int gfs2_quota_hold(struct gfs2_inode *ip, u32 uid, u32 gid)
 492 {
 493         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 494         struct gfs2_alloc *al = ip->i_alloc;
 495         struct gfs2_quota_data **qd = al->al_qd;
 496         int error;
 497
 498         if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
 499             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
 500                 return -EIO;
 501
 502         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 503                 return 0;
 504
 505         error = qdsb_get(sdp, QUOTA_USER, ip->i_inode.i_uid, qd);
 506         if (error)
 507                 goto out;
 508         al->al_qd_num++;
 509         qd++;
 510
 511         error = qdsb_get(sdp, QUOTA_GROUP, ip->i_inode.i_gid, qd);
 512         if (error)
 513                 goto out;
 514         al->al_qd_num++;
 515         qd++;
 516
 517         if (uid != NO_QUOTA_CHANGE && uid != ip->i_inode.i_uid) {
 518                 error = qdsb_get(sdp, QUOTA_USER, uid, qd);
 519                 if (error)
 520                         goto out;
 521                 al->al_qd_num++;
 522                 qd++;
 523         }
 524
 525         if (gid != NO_QUOTA_CHANGE && gid != ip->i_inode.i_gid) {
 526                 error = qdsb_get(sdp, QUOTA_GROUP, gid, qd);
 527                 if (error)
 528                         goto out;
 529                 al->al_qd_num++;
 530                 qd++;
 531         }
 532
 533 out:
 534         if (error)
 535                 gfs2_quota_unhold(ip);
 536         return error;
 537 }
 538
 539 void gfs2_quota_unhold(struct gfs2_inode *ip)
 540 {
 541         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 542         struct gfs2_alloc *al = ip->i_alloc;
 543         unsigned int x;
 544
 545         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 546
 547         for (x = 0; x < al->al_qd_num; x++) {
 548                 qdsb_put(al->al_qd[x]);
 549                 al->al_qd[x] = NULL;
 550         }
 551         al->al_qd_num = 0;
 552 }
 553
 554 static int sort_qd(const void *a, const void *b)
 555 {
 556         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
 557         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
 558
 559         if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
 560             !test_bit(QDF_USER, &qd_b->qd_flags)) {
 561                 if (test_bit(QDF_USER, &qd_a->qd_flags))
 562                         return -1;
 563                 else
 564                         return 1;
 565         }
 566         if (qd_a->qd_id < qd_b->qd_id)
 567                 return -1;
 568         if (qd_a->qd_id > qd_b->qd_id)
 569                 return 1;
 570
 571         return 0;
 572 }
 573
 574 static void do_qc(struct gfs2_quota_data *qd, s64 change)
 575 {
 576         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 577         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 578         struct gfs2_quota_change *qc = qd->qd_bh_qc;
 579         s64 x;
 580
 581         mutex_lock(&sdp->sd_quota_mutex);
 582         gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
 583
 584         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
 585                 qc->qc_change = 0;
 586                 qc->qc_flags = 0;
 587                 if (test_bit(QDF_USER, &qd->qd_flags))
 588                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
 589                 qc->qc_id = cpu_to_be32(qd->qd_id);
 590         }
 591
 592         x = be64_to_cpu(qc->qc_change) + change;
 593         qc->qc_change = cpu_to_be64(x);
 594
 595         spin_lock(&qd_lru_lock);
 596         qd->qd_change = x;
 597         spin_unlock(&qd_lru_lock);
 598
 599         if (!x) {
 600                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
 601                 clear_bit(QDF_CHANGE, &qd->qd_flags);
 602                 qc->qc_flags = 0;
 603                 qc->qc_id = 0;
 604                 slot_put(qd);
 605                 qd_put(qd);
 606         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
 607                 qd_hold(qd);
 608                 slot_hold(qd);
 609         }
 610
 611         mutex_unlock(&sdp->sd_quota_mutex);
 612 }
 613
 614 /**
 615  * gfs2_adjust_quota - adjust record of current block usage
 616  * @ip: The quota inode
 617  * @loc: Offset of the entry in the quota file
 618  * @change: The amount of change to record
 619  * @qd: The quota data
 620  *
 621  * This function was mostly borrowed from gfs2_block_truncate_page which was
 622  * in turn mostly borrowed from ext3
 623  *
 624  * Returns: 0 or -ve on error
 625  */
 626
 627 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 628                              s64 change, struct gfs2_quota_data *qd)
 629 {
 630         struct inode *inode = &ip->i_inode;
 631         struct address_space *mapping = inode->i_mapping;
 632         unsigned long index = loc >> PAGE_CACHE_SHIFT;
 633         unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
 634         unsigned blocksize, iblock, pos;
 635         struct buffer_head *bh;
 636         struct page *page;
 637         void *kaddr;
 638         struct gfs2_quota *qp;
 639         s64 value;
 640         int err = -EIO;
 641
 642         if (gfs2_is_stuffed(ip))
 643                 gfs2_unstuff_dinode(ip, NULL);
 644
 645         page = grab_cache_page(mapping, index);
 646         if (!page)
 647                 return -ENOMEM;
 648
 649         blocksize = inode->i_sb->s_blocksize;
 650         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
 651
 652         if (!page_has_buffers(page))
 653                 create_empty_buffers(page, blocksize, 0);
 654
 655         bh = page_buffers(page);
 656         pos = blocksize;
 657         while (offset >= pos) {
 658                 bh = bh->b_this_page;
 659                 iblock++;
 660                 pos += blocksize;
 661         }
 662
 663         if (!buffer_mapped(bh)) {
 664                 gfs2_block_map(inode, iblock, bh, 1);
 665                 if (!buffer_mapped(bh))
 666                         goto unlock;
 667         }
 668
 669         if (PageUptodate(page))
 670                 set_buffer_uptodate(bh);
 671
 672         if (!buffer_uptodate(bh)) {
 673                 ll_rw_block(READ_META, 1, &bh);
 674                 wait_on_buffer(bh);
 675                 if (!buffer_uptodate(bh))
 676                         goto unlock;
 677         }
 678
 679         gfs2_trans_add_bh(ip->i_gl, bh, 0);
 680
 681         kaddr = kmap_atomic(page, KM_USER0);
 682         qp = kaddr + offset;
 683         value = (s64)be64_to_cpu(qp->qu_value) + change;
 684         qp->qu_value = cpu_to_be64(value);
 685         qd->qd_qb.qb_value = qp->qu_value;
 686         flush_dcache_page(page);
 687         kunmap_atomic(kaddr, KM_USER0);
 688         err = 0;
 689 unlock:
 690         unlock_page(page);
 691         page_cache_release(page);
 692         return err;
 693 }
 694
 695 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 696 {
 697         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
 698         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 699         unsigned int data_blocks, ind_blocks;
 700         struct gfs2_holder *ghs, i_gh;
 701         unsigned int qx, x;
 702         struct gfs2_quota_data *qd;
 703         loff_t offset;
 704         unsigned int nalloc = 0, blocks;
 705         struct gfs2_alloc *al = NULL;
 706         int error;
 707
 708         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 709                               &data_blocks, &ind_blocks);
 710
 711         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
 712         if (!ghs)
 713                 return -ENOMEM;
 714
 715         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 716         for (qx = 0; qx < num_qd; qx++) {
 717                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
 718                                            GL_NOCACHE, &ghs[qx]);
 719                 if (error)
 720                         goto out;
 721         }
 722
 723         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 724         if (error)
 725                 goto out;
 726
 727         for (x = 0; x < num_qd; x++) {
 728                 int alloc_required;
 729
 730                 offset = qd2offset(qda[x]);
 731                 error = gfs2_write_alloc_required(ip, offset,
 732                                                   sizeof(struct gfs2_quota),
 733                                                   &alloc_required);
 734                 if (error)
 735                         goto out_gunlock;
 736                 if (alloc_required)
 737                         nalloc++;
 738         }
 739
 740         al = gfs2_alloc_get(ip);
 741         if (!al) {
 742                 error = -ENOMEM;
 743                 goto out_gunlock;
 744         }
 745         /*
 746          * 1 blk for unstuffing inode if stuffed. We add this extra
 747          * block to the reservation unconditionally. If the inode
 748          * doesn't need unstuffing, the block will be released to the
 749          * rgrp since it won't be allocated during the transaction
 750          */
 751         al->al_requested = 1;
 752         /* +1 in the end for block requested above for unstuffing */
 753         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 1;
 754
 755         if (nalloc)
 756                 al->al_requested += nalloc * (data_blocks + ind_blocks);
 757         error = gfs2_inplace_reserve(ip);
 758         if (error)
 759                 goto out_alloc;
 760
 761         if (nalloc)
 762                 blocks += al->al_rgd->rd_length + nalloc * ind_blocks + RES_STATFS;
 763
 764         error = gfs2_trans_begin(sdp, blocks, 0);
 765         if (error)
 766                 goto out_ipres;
 767
 768         for (x = 0; x < num_qd; x++) {
 769                 qd = qda[x];
 770                 offset = qd2offset(qd);
 771                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync,
 772                                           (struct gfs2_quota_data *)qd);
 773                 if (error)
 774                         goto out_end_trans;
 775
 776                 do_qc(qd, -qd->qd_change_sync);
 777         }
 778
 779         error = 0;
 780
 781 out_end_trans:
 782         gfs2_trans_end(sdp);
 783 out_ipres:
 784         gfs2_inplace_release(ip);
 785 out_alloc:
 786         gfs2_alloc_put(ip);
 787 out_gunlock:
 788         gfs2_glock_dq_uninit(&i_gh);
 789 out:
 790         while (qx--)
 791                 gfs2_glock_dq_uninit(&ghs[qx]);
 792         kfree(ghs);
 793         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
 794         return error;
 795 }
 796
 797 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 798                     struct gfs2_holder *q_gh)
 799 {
 800         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 801         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 802         struct gfs2_holder i_gh;
 803         struct gfs2_quota q;
 804         int error;
 805         struct gfs2_quota_lvb *qlvb;
 806
 807 restart:
 808         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 809         if (error)
 810                 return error;
 811
 812         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 813
 814         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
 815                 loff_t pos;
 816                 gfs2_glock_dq_uninit(q_gh);
 817                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
 818                                            GL_NOCACHE, q_gh);
 819                 if (error)
 820                         return error;
 821
 822                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
 823                 if (error)
 824                         goto fail;
 825
 826                 memset(&q, 0, sizeof(struct gfs2_quota));
 827                 pos = qd2offset(qd);
 828                 error = gfs2_internal_read(ip, NULL, (char *)&q, &pos, sizeof(q));
 829                 if (error < 0)
 830                         goto fail_gunlock;
 831                 if ((error < sizeof(q)) && force_refresh) {
 832                         error = -ENOENT;
 833                         goto fail_gunlock;
 834                 }
 835                 gfs2_glock_dq_uninit(&i_gh);
 836
 837                 qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 838                 qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
 839                 qlvb->__pad = 0;
 840                 qlvb->qb_limit = q.qu_limit;
 841                 qlvb->qb_warn = q.qu_warn;
 842                 qlvb->qb_value = q.qu_value;
 843                 qd->qd_qb = *qlvb;
 844
 845                 gfs2_glock_dq_uninit(q_gh);
 846                 force_refresh = 0;
 847                 goto restart;
 848         }
 849
 850         return 0;
 851
 852 fail_gunlock:
 853         gfs2_glock_dq_uninit(&i_gh);
 854 fail:
 855         gfs2_glock_dq_uninit(q_gh);
 856         return error;
 857 }
 858
 859 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
 860 {
 861         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 862         struct gfs2_alloc *al = ip->i_alloc;
 863         unsigned int x;
 864         int error = 0;
 865
 866         gfs2_quota_hold(ip, uid, gid);
 867
 868         if (capable(CAP_SYS_RESOURCE) ||
 869             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 870                 return 0;
 871
 872         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
 873              sort_qd, NULL);
 874
 875         for (x = 0; x < al->al_qd_num; x++) {
 876                 error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
 877                 if (error)
 878                         break;
 879         }
 880
 881         if (!error)
 882                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
 883         else {
 884                 while (x--)
 885                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 886                 gfs2_quota_unhold(ip);
 887         }
 888
 889         return error;
 890 }
 891
 892 static int need_sync(struct gfs2_quota_data *qd)
 893 {
 894         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 895         struct gfs2_tune *gt = &sdp->sd_tune;
 896         s64 value;
 897         unsigned int num, den;
 898         int do_sync = 1;
 899
 900         if (!qd->qd_qb.qb_limit)
 901                 return 0;
 902
 903         spin_lock(&qd_lru_lock);
 904         value = qd->qd_change;
 905         spin_unlock(&qd_lru_lock);
 906
 907         spin_lock(&gt->gt_spin);
 908         num = gt->gt_quota_scale_num;
 909         den = gt->gt_quota_scale_den;
 910         spin_unlock(&gt->gt_spin);
 911
 912         if (value < 0)
 913                 do_sync = 0;
 914         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
 915                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 916                 do_sync = 0;
 917         else {
 918                 value *= gfs2_jindex_size(sdp) * num;
 919                 value = div_s64(value, den);
 920                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
 921                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 922                         do_sync = 0;
 923         }
 924
 925         return do_sync;
 926 }
 927
 928 void gfs2_quota_unlock(struct gfs2_inode *ip)
 929 {
 930         struct gfs2_alloc *al = ip->i_alloc;
 931         struct gfs2_quota_data *qda[4];
 932         unsigned int count = 0;
 933         unsigned int x;
 934
 935         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
 936                 goto out;
 937
 938         for (x = 0; x < al->al_qd_num; x++) {
 939                 struct gfs2_quota_data *qd;
 940                 int sync;
 941
 942                 qd = al->al_qd[x];
 943                 sync = need_sync(qd);
 944
 945                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 946
 947                 if (sync && qd_trylock(qd))
 948                         qda[count++] = qd;
 949         }
 950
 951         if (count) {
 952                 do_sync(count, qda);
 953                 for (x = 0; x < count; x++)
 954                         qd_unlock(qda[x]);
 955         }
 956
 957 out:
 958         gfs2_quota_unhold(ip);
 959 }
 960
 961 #define MAX_LINE 256
 962
 963 static int print_message(struct gfs2_quota_data *qd, char *type)
 964 {
 965         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 966
 967         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\r\n",
 968                sdp->sd_fsname, type,
 969                (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
 970                qd->qd_id);
 971
 972         return 0;
 973 }
 974
 975 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
 976 {
 977         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 978         struct gfs2_alloc *al = ip->i_alloc;
 979         struct gfs2_quota_data *qd;
 980         s64 value;
 981         unsigned int x;
 982         int error = 0;
 983
 984         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
 985                 return 0;
 986
 987         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 988                 return 0;
 989
 990         for (x = 0; x < al->al_qd_num; x++) {
 991                 qd = al->al_qd[x];
 992
 993                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
 994                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
 995                         continue;
 996
 997                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
 998                 spin_lock(&qd_lru_lock);
 999                 value += qd->qd_change;
1000                 spin_unlock(&qd_lru_lock);
1001
1002                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
1003                         print_message(qd, "exceeded");
1004                         error = -EDQUOT;
1005                         break;
1006                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
1007                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
1008                            time_after_eq(jiffies, qd->qd_last_warn +
1009                                          gfs2_tune_get(sdp,
1010                                                 gt_quota_warn_period) * HZ)) {
1011                         error = print_message(qd, "warning");
1012                         qd->qd_last_warn = jiffies;
1013                 }
1014         }
1015
1016         return error;
1017 }
1018
1019 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1020                        u32 uid, u32 gid)
1021 {
1022         struct gfs2_alloc *al = ip->i_alloc;
1023         struct gfs2_quota_data *qd;
1024         unsigned int x;
1025
1026         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1027                 return;
1028         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1029                 return;
1030
1031         for (x = 0; x < al->al_qd_num; x++) {
1032                 qd = al->al_qd[x];
1033
1034                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1035                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
1036                         do_qc(qd, change);
1037                 }
1038         }
1039 }
1040
1041 int gfs2_quota_sync(struct super_block *sb, int type)
1042 {
1043         struct gfs2_sbd *sdp = sb->s_fs_info;
1044         struct gfs2_quota_data **qda;
1045         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1046         unsigned int num_qd;
1047         unsigned int x;
1048         int error = 0;
1049
1050         sdp->sd_quota_sync_gen++;
1051
1052         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1053         if (!qda)
1054                 return -ENOMEM;
1055
1056         do {
1057                 num_qd = 0;
1058
1059                 for (;;) {
1060                         error = qd_fish(sdp, qda + num_qd);
1061                         if (error || !qda[num_qd])
1062                                 break;
1063                         if (++num_qd == max_qd)
1064                                 break;
1065                 }
1066
1067                 if (num_qd) {
1068                         if (!error)
1069                                 error = do_sync(num_qd, qda);
1070                         if (!error)
1071                                 for (x = 0; x < num_qd; x++)
1072                                         qda[x]->qd_sync_gen =
1073                                                 sdp->sd_quota_sync_gen;
1074
1075                         for (x = 0; x < num_qd; x++)
1076                                 qd_unlock(qda[x]);
1077                 }
1078         } while (!error && num_qd == max_qd);
1079
1080         kfree(qda);
1081
1082         return error;
1083 }
1084
1085 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1086 {
1087         struct gfs2_quota_data *qd;
1088         struct gfs2_holder q_gh;
1089         int error;
1090
1091         error = qd_get(sdp, user, id, &qd);
1092         if (error)
1093                 return error;
1094
1095         error = do_glock(qd, FORCE, &q_gh);
1096         if (!error)
1097                 gfs2_glock_dq_uninit(&q_gh);
1098
1099         qd_put(qd);
1100         return error;
1101 }
1102
1103 static void gfs2_quota_change_in(struct gfs2_quota_change_host *qc, const void *buf)
1104 {
1105         const struct gfs2_quota_change *str = buf;
1106
1107         qc->qc_change = be64_to_cpu(str->qc_change);
1108         qc->qc_flags = be32_to_cpu(str->qc_flags);
1109         qc->qc_id = be32_to_cpu(str->qc_id);
1110 }
1111
1112 int gfs2_quota_init(struct gfs2_sbd *sdp)
1113 {
1114         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1115         unsigned int blocks = ip->i_disksize >> sdp->sd_sb.sb_bsize_shift;
1116         unsigned int x, slot = 0;
1117         unsigned int found = 0;
1118         u64 dblock;
1119         u32 extlen = 0;
1120         int error;
1121
1122         if (!ip->i_disksize || ip->i_disksize > (64 << 20) ||
1123             ip->i_disksize & (sdp->sd_sb.sb_bsize - 1)) {
1124                 gfs2_consist_inode(ip);
1125                 return -EIO;
1126         }
1127         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1128         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1129
1130         error = -ENOMEM;
1131
1132         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1133                                        sizeof(unsigned char *), GFP_NOFS);
1134         if (!sdp->sd_quota_bitmap)
1135                 return error;
1136
1137         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1138                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_NOFS);
1139                 if (!sdp->sd_quota_bitmap[x])
1140                         goto fail;
1141         }
1142
1143         for (x = 0; x < blocks; x++) {
1144                 struct buffer_head *bh;
1145                 unsigned int y;
1146
1147                 if (!extlen) {
1148                         int new = 0;
1149                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1150                         if (error)
1151                                 goto fail;
1152                 }
1153                 error = -EIO;
1154                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1155                 if (!bh)
1156                         goto fail;
1157                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1158                         brelse(bh);
1159                         goto fail;
1160                 }
1161
1162                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1163                      y++, slot++) {
1164                         struct gfs2_quota_change_host qc;
1165                         struct gfs2_quota_data *qd;
1166
1167                         gfs2_quota_change_in(&qc, bh->b_data +
1168                                           sizeof(struct gfs2_meta_header) +
1169                                           y * sizeof(struct gfs2_quota_change));
1170                         if (!qc.qc_change)
1171                                 continue;
1172
1173                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1174                                          qc.qc_id, &qd);
1175                         if (error) {
1176                                 brelse(bh);
1177                                 goto fail;
1178                         }
1179
1180                         set_bit(QDF_CHANGE, &qd->qd_flags);
1181                         qd->qd_change = qc.qc_change;
1182                         qd->qd_slot = slot;
1183                         qd->qd_slot_count = 1;
1184
1185                         spin_lock(&qd_lru_lock);
1186                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1187                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1188                         atomic_inc(&sdp->sd_quota_count);
1189                         spin_unlock(&qd_lru_lock);
1190
1191                         found++;
1192                 }
1193
1194                 brelse(bh);
1195                 dblock++;
1196                 extlen--;
1197         }
1198
1199         if (found)
1200                 fs_info(sdp, "found %u quota changes\n", found);
1201
1202         return 0;
1203
1204 fail:
1205         gfs2_quota_cleanup(sdp);
1206         return error;
1207 }
1208
1209 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1210 {
1211         struct list_head *head = &sdp->sd_quota_list;
1212         struct gfs2_quota_data *qd;
1213         unsigned int x;
1214
1215         spin_lock(&qd_lru_lock);
1216         while (!list_empty(head)) {
1217                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1218
1219                 if (atomic_read(&qd->qd_count) > 1 ||
1220                     (atomic_read(&qd->qd_count) &&
1221                      !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1222                         list_move(&qd->qd_list, head);
1223                         spin_unlock(&qd_lru_lock);
1224                         schedule();
1225                         spin_lock(&qd_lru_lock);
1226                         continue;
1227                 }
1228
1229                 list_del(&qd->qd_list);
1230                 /* Also remove if this qd exists in the reclaim list */
1231                 if (!list_empty(&qd->qd_reclaim)) {
1232                         list_del_init(&qd->qd_reclaim);
1233                         atomic_dec(&qd_lru_count);
1234                 }
1235                 atomic_dec(&sdp->sd_quota_count);
1236                 spin_unlock(&qd_lru_lock);
1237
1238                 if (!atomic_read(&qd->qd_count)) {
1239                         gfs2_assert_warn(sdp, !qd->qd_change);
1240                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1241                 } else
1242                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1243                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1244
1245                 gfs2_glock_put(qd->qd_gl);
1246                 kmem_cache_free(gfs2_quotad_cachep, qd);
1247
1248                 spin_lock(&qd_lru_lock);
1249         }
1250         spin_unlock(&qd_lru_lock);
1251
1252         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1253
1254         if (sdp->sd_quota_bitmap) {
1255                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1256                         kfree(sdp->sd_quota_bitmap[x]);
1257                 kfree(sdp->sd_quota_bitmap);
1258         }
1259 }
1260
1261 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1262 {
1263         if (error == 0 || error == -EROFS)
1264                 return;
1265         if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1266                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1267 }
1268
1269 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1270                                int (*fxn)(struct super_block *sb, int type),
1271                                unsigned long t, unsigned long *timeo,
1272                                unsigned int *new_timeo)
1273 {
1274         if (t >= *timeo) {
1275                 int error = fxn(sdp->sd_vfs, 0);
1276                 quotad_error(sdp, msg, error);
1277                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1278         } else {
1279                 *timeo -= t;
1280         }
1281 }
1282
1283 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1284 {
1285         struct gfs2_inode *ip;
1286
1287         while(1) {
1288                 ip = NULL;
1289                 spin_lock(&sdp->sd_trunc_lock);
1290                 if (!list_empty(&sdp->sd_trunc_list)) {
1291                         ip = list_entry(sdp->sd_trunc_list.next,
1292                                         struct gfs2_inode, i_trunc_list);
1293                         list_del_init(&ip->i_trunc_list);
1294                 }
1295                 spin_unlock(&sdp->sd_trunc_lock);
1296                 if (ip == NULL)
1297                         return;
1298                 gfs2_glock_finish_truncate(ip);
1299         }
1300 }
1301
1302 /**
1303  * gfs2_quotad - Write cached quota changes into the quota file
1304  * @sdp: Pointer to GFS2 superblock
1305  *
1306  */
1307
1308 int gfs2_quotad(void *data)
1309 {
1310         struct gfs2_sbd *sdp = data;
1311         struct gfs2_tune *tune = &sdp->sd_tune;
1312         unsigned long statfs_timeo = 0;
1313         unsigned long quotad_timeo = 0;
1314         unsigned long t = 0;
1315         DEFINE_WAIT(wait);
1316         int empty;
1317
1318         while (!kthread_should_stop()) {
1319
1320                 /* Update the master statfs file */
1321                 quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1322                                    &statfs_timeo, &tune->gt_statfs_quantum);
1323
1324                 /* Update quota file */
1325                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1326                                    &quotad_timeo, &tune->gt_quota_quantum);
1327
1328                 /* Check for & recover partially truncated inodes */
1329                 quotad_check_trunc_list(sdp);
1330
1331                 if (freezing(current))
1332                         refrigerator();
1333                 t = min(quotad_timeo, statfs_timeo);
1334
1335                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1336                 spin_lock(&sdp->sd_trunc_lock);
1337                 empty = list_empty(&sdp->sd_trunc_list);
1338                 spin_unlock(&sdp->sd_trunc_lock);
1339                 if (empty)
1340                         t -= schedule_timeout(t);
1341                 else
1342                         t = 0;
1343                 finish_wait(&sdp->sd_quota_wait, &wait);
1344         }
1345
1346         return 0;
1347 }
1348
1349 static int gfs2_quota_get_xstate(struct super_block *sb,
1350                                  struct fs_quota_stat *fqs)
1351 {
1352         struct gfs2_sbd *sdp = sb->s_fs_info;
1353
1354         memset(fqs, 0, sizeof(struct fs_quota_stat));
1355         fqs->qs_version = FS_QSTAT_VERSION;
1356         if (sdp->sd_args.ar_quota == GFS2_QUOTA_ON)
1357                 fqs->qs_flags = (XFS_QUOTA_UDQ_ENFD | XFS_QUOTA_GDQ_ENFD);
1358         else if (sdp->sd_args.ar_quota == GFS2_QUOTA_ACCOUNT)
1359                 fqs->qs_flags = (XFS_QUOTA_UDQ_ACCT | XFS_QUOTA_GDQ_ACCT);
1360         if (sdp->sd_quota_inode) {
1361                 fqs->qs_uquota.qfs_ino = GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1362                 fqs->qs_uquota.qfs_nblks = sdp->sd_quota_inode->i_blocks;
1363         }
1364         fqs->qs_uquota.qfs_nextents = 1; /* unsupported */
1365         fqs->qs_gquota = fqs->qs_uquota; /* its the same inode in both cases */
1366         fqs->qs_incoredqs = atomic_read(&qd_lru_count);
1367         return 0;
1368 }
1369
1370 const struct quotactl_ops gfs2_quotactl_ops = {
1371         .quota_sync     = gfs2_quota_sync,
1372         .get_xstate     = gfs2_quota_get_xstate,
1373 };
1374