fs/gfs2/quota.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
   4  *
   5  * This copyrighted material is made available to anyone wishing to use,
   6  * modify, copy, or redistribute it subject to the terms and conditions
   7  * of the GNU General Public License version 2.
   8  */
   9
  10 /*
  11  * Quota change tags are associated with each transaction that allocates or
  12  * deallocates space.  Those changes are accumulated locally to each node (in a
  13  * per-node file) and then are periodically synced to the quota file.  This
  14  * avoids the bottleneck of constantly touching the quota file, but introduces
  15  * fuzziness in the current usage value of IDs that are being used on different
  16  * nodes in the cluster simultaneously.  So, it is possible for a user on
  17  * multiple nodes to overrun their quota, but that overrun is controlable.
  18  * Since quota tags are part of transactions, there is no need for a quota check
  19  * program to be run on node crashes or anything like that.
  20  *
  21  * There are couple of knobs that let the administrator manage the quota
  22  * fuzziness.  "quota_quantum" sets the maximum time a quota change can be
  23  * sitting on one node before being synced to the quota file.  (The default is
  24  * 60 seconds.)  Another knob, "quota_scale" controls how quickly the frequency
  25  * of quota file syncs increases as the user moves closer to their limit.  The
  26  * more frequent the syncs, the more accurate the quota enforcement, but that
  27  * means that there is more contention between the nodes for the quota file.
  28  * The default value is one.  This sets the maximum theoretical quota overrun
  29  * (with infinite node with infinite bandwidth) to twice the user's limit.  (In
  30  * practice, the maximum overrun you see should be much less.)  A "quota_scale"
  31  * number greater than one makes quota syncs more frequent and reduces the
  32  * maximum overrun.  Numbers less than one (but greater than zero) make quota
  33  * syncs less frequent.
  34  *
  35  * GFS quotas also use per-ID Lock Value Blocks (LVBs) to cache the contents of
  36  * the quota file, so it is not being constantly read.
  37  */
  38
  39 #include <linux/sched.h>
  40 #include <linux/slab.h>
  41 #include <linux/mm.h>
  42 #include <linux/spinlock.h>
  43 #include <linux/completion.h>
  44 #include <linux/buffer_head.h>
  45 #include <linux/sort.h>
  46 #include <linux/fs.h>
  47 #include <linux/bio.h>
  48 #include <linux/gfs2_ondisk.h>
  49 #include <linux/kthread.h>
  50 #include <linux/freezer.h>
  51 #include <linux/quota.h>
  52 #include <linux/dqblk_xfs.h>
  53
  54 #include "gfs2.h"
  55 #include "incore.h"
  56 #include "bmap.h"
  57 #include "glock.h"
  58 #include "glops.h"
  59 #include "log.h"
  60 #include "meta_io.h"
  61 #include "quota.h"
  62 #include "rgrp.h"
  63 #include "super.h"
  64 #include "trans.h"
  65 #include "inode.h"
  66 #include "util.h"
  67
  68 #define QUOTA_USER 1
  69 #define QUOTA_GROUP 0
  70
  71 struct gfs2_quota_change_host {
  72         u64 qc_change;
  73         u32 qc_flags; /* GFS2_QCF_... */
  74         u32 qc_id;
  75 };
  76
  77 static LIST_HEAD(qd_lru_list);
  78 static atomic_t qd_lru_count = ATOMIC_INIT(0);
  79 static DEFINE_SPINLOCK(qd_lru_lock);
  80
  81 int gfs2_shrink_qd_memory(struct shrinker *shrink, struct shrink_control *sc)
  82 {
  83         struct gfs2_quota_data *qd;
  84         struct gfs2_sbd *sdp;
  85         int nr_to_scan = sc->nr_to_scan;
  86
  87         if (nr_to_scan == 0)
  88                 goto out;
  89
  90         if (!(sc->gfp_mask & __GFP_FS))
  91                 return -1;
  92
  93         spin_lock(&qd_lru_lock);
  94         while (nr_to_scan && !list_empty(&qd_lru_list)) {
  95                 qd = list_entry(qd_lru_list.next,
  96                                 struct gfs2_quota_data, qd_reclaim);
  97                 sdp = qd->qd_gl->gl_sbd;
  98
  99                 /* Free from the filesystem-specific list */
 100                 list_del(&qd->qd_list);
 101
 102                 gfs2_assert_warn(sdp, !qd->qd_change);
 103                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
 104                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
 105
 106                 gfs2_glock_put(qd->qd_gl);
 107                 atomic_dec(&sdp->sd_quota_count);
 108
 109                 /* Delete it from the common reclaim list */
 110                 list_del_init(&qd->qd_reclaim);
 111                 atomic_dec(&qd_lru_count);
 112                 spin_unlock(&qd_lru_lock);
 113                 kmem_cache_free(gfs2_quotad_cachep, qd);
 114                 spin_lock(&qd_lru_lock);
 115                 nr_to_scan--;
 116         }
 117         spin_unlock(&qd_lru_lock);
 118
 119 out:
 120         return (atomic_read(&qd_lru_count) * sysctl_vfs_cache_pressure) / 100;
 121 }
 122
 123 static u64 qd2offset(struct gfs2_quota_data *qd)
 124 {
 125         u64 offset;
 126
 127         offset = 2 * (u64)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
 128         offset *= sizeof(struct gfs2_quota);
 129
 130         return offset;
 131 }
 132
 133 static int qd_alloc(struct gfs2_sbd *sdp, int user, u32 id,
 134                     struct gfs2_quota_data **qdp)
 135 {
 136         struct gfs2_quota_data *qd;
 137         int error;
 138
 139         qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
 140         if (!qd)
 141                 return -ENOMEM;
 142
 143         atomic_set(&qd->qd_count, 1);
 144         qd->qd_id = id;
 145         if (user)
 146                 set_bit(QDF_USER, &qd->qd_flags);
 147         qd->qd_slot = -1;
 148         INIT_LIST_HEAD(&qd->qd_reclaim);
 149
 150         error = gfs2_glock_get(sdp, 2 * (u64)id + !user,
 151                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
 152         if (error)
 153                 goto fail;
 154
 155         *qdp = qd;
 156
 157         return 0;
 158
 159 fail:
 160         kmem_cache_free(gfs2_quotad_cachep, qd);
 161         return error;
 162 }
 163
 164 static int qd_get(struct gfs2_sbd *sdp, int user, u32 id,
 165                   struct gfs2_quota_data **qdp)
 166 {
 167         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
 168         int error, found;
 169
 170         *qdp = NULL;
 171
 172         for (;;) {
 173                 found = 0;
 174                 spin_lock(&qd_lru_lock);
 175                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 176                         if (qd->qd_id == id &&
 177                             !test_bit(QDF_USER, &qd->qd_flags) == !user) {
 178                                 if (!atomic_read(&qd->qd_count) &&
 179                                     !list_empty(&qd->qd_reclaim)) {
 180                                         /* Remove it from reclaim list */
 181                                         list_del_init(&qd->qd_reclaim);
 182                                         atomic_dec(&qd_lru_count);
 183                                 }
 184                                 atomic_inc(&qd->qd_count);
 185                                 found = 1;
 186                                 break;
 187                         }
 188                 }
 189
 190                 if (!found)
 191                         qd = NULL;
 192
 193                 if (!qd && new_qd) {
 194                         qd = new_qd;
 195                         list_add(&qd->qd_list, &sdp->sd_quota_list);
 196                         atomic_inc(&sdp->sd_quota_count);
 197                         new_qd = NULL;
 198                 }
 199
 200                 spin_unlock(&qd_lru_lock);
 201
 202                 if (qd) {
 203                         if (new_qd) {
 204                                 gfs2_glock_put(new_qd->qd_gl);
 205                                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
 206                         }
 207                         *qdp = qd;
 208                         return 0;
 209                 }
 210
 211                 error = qd_alloc(sdp, user, id, &new_qd);
 212                 if (error)
 213                         return error;
 214         }
 215 }
 216
 217 static void qd_hold(struct gfs2_quota_data *qd)
 218 {
 219         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 220         gfs2_assert(sdp, atomic_read(&qd->qd_count));
 221         atomic_inc(&qd->qd_count);
 222 }
 223
 224 static void qd_put(struct gfs2_quota_data *qd)
 225 {
 226         if (atomic_dec_and_lock(&qd->qd_count, &qd_lru_lock)) {
 227                 /* Add to the reclaim list */
 228                 list_add_tail(&qd->qd_reclaim, &qd_lru_list);
 229                 atomic_inc(&qd_lru_count);
 230                 spin_unlock(&qd_lru_lock);
 231         }
 232 }
 233
 234 static int slot_get(struct gfs2_quota_data *qd)
 235 {
 236         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 237         unsigned int c, o = 0, b;
 238         unsigned char byte = 0;
 239
 240         spin_lock(&qd_lru_lock);
 241
 242         if (qd->qd_slot_count++) {
 243                 spin_unlock(&qd_lru_lock);
 244                 return 0;
 245         }
 246
 247         for (c = 0; c < sdp->sd_quota_chunks; c++)
 248                 for (o = 0; o < PAGE_SIZE; o++) {
 249                         byte = sdp->sd_quota_bitmap[c][o];
 250                         if (byte != 0xFF)
 251                                 goto found;
 252                 }
 253
 254         goto fail;
 255
 256 found:
 257         for (b = 0; b < 8; b++)
 258                 if (!(byte & (1 << b)))
 259                         break;
 260         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
 261
 262         if (qd->qd_slot >= sdp->sd_quota_slots)
 263                 goto fail;
 264
 265         sdp->sd_quota_bitmap[c][o] |= 1 << b;
 266
 267         spin_unlock(&qd_lru_lock);
 268
 269         return 0;
 270
 271 fail:
 272         qd->qd_slot_count--;
 273         spin_unlock(&qd_lru_lock);
 274         return -ENOSPC;
 275 }
 276
 277 static void slot_hold(struct gfs2_quota_data *qd)
 278 {
 279         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 280
 281         spin_lock(&qd_lru_lock);
 282         gfs2_assert(sdp, qd->qd_slot_count);
 283         qd->qd_slot_count++;
 284         spin_unlock(&qd_lru_lock);
 285 }
 286
 287 static void slot_put(struct gfs2_quota_data *qd)
 288 {
 289         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 290
 291         spin_lock(&qd_lru_lock);
 292         gfs2_assert(sdp, qd->qd_slot_count);
 293         if (!--qd->qd_slot_count) {
 294                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
 295                 qd->qd_slot = -1;
 296         }
 297         spin_unlock(&qd_lru_lock);
 298 }
 299
 300 static int bh_get(struct gfs2_quota_data *qd)
 301 {
 302         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 303         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 304         unsigned int block, offset;
 305         struct buffer_head *bh;
 306         int error;
 307         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
 308
 309         mutex_lock(&sdp->sd_quota_mutex);
 310
 311         if (qd->qd_bh_count++) {
 312                 mutex_unlock(&sdp->sd_quota_mutex);
 313                 return 0;
 314         }
 315
 316         block = qd->qd_slot / sdp->sd_qc_per_block;
 317         offset = qd->qd_slot % sdp->sd_qc_per_block;
 318
 319         bh_map.b_size = 1 << ip->i_inode.i_blkbits;
 320         error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
 321         if (error)
 322                 goto fail;
 323         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
 324         if (error)
 325                 goto fail;
 326         error = -EIO;
 327         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
 328                 goto fail_brelse;
 329
 330         qd->qd_bh = bh;
 331         qd->qd_bh_qc = (struct gfs2_quota_change *)
 332                 (bh->b_data + sizeof(struct gfs2_meta_header) +
 333                  offset * sizeof(struct gfs2_quota_change));
 334
 335         mutex_unlock(&sdp->sd_quota_mutex);
 336
 337         return 0;
 338
 339 fail_brelse:
 340         brelse(bh);
 341 fail:
 342         qd->qd_bh_count--;
 343         mutex_unlock(&sdp->sd_quota_mutex);
 344         return error;
 345 }
 346
 347 static void bh_put(struct gfs2_quota_data *qd)
 348 {
 349         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 350
 351         mutex_lock(&sdp->sd_quota_mutex);
 352         gfs2_assert(sdp, qd->qd_bh_count);
 353         if (!--qd->qd_bh_count) {
 354                 brelse(qd->qd_bh);
 355                 qd->qd_bh = NULL;
 356                 qd->qd_bh_qc = NULL;
 357         }
 358         mutex_unlock(&sdp->sd_quota_mutex);
 359 }
 360
 361 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
 362 {
 363         struct gfs2_quota_data *qd = NULL;
 364         int error;
 365         int found = 0;
 366
 367         *qdp = NULL;
 368
 369         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 370                 return 0;
 371
 372         spin_lock(&qd_lru_lock);
 373
 374         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 375                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 376                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
 377                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
 378                         continue;
 379
 380                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 381
 382                 set_bit(QDF_LOCKED, &qd->qd_flags);
 383                 gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
 384                 atomic_inc(&qd->qd_count);
 385                 qd->qd_change_sync = qd->qd_change;
 386                 gfs2_assert_warn(sdp, qd->qd_slot_count);
 387                 qd->qd_slot_count++;
 388                 found = 1;
 389
 390                 break;
 391         }
 392
 393         if (!found)
 394                 qd = NULL;
 395
 396         spin_unlock(&qd_lru_lock);
 397
 398         if (qd) {
 399                 gfs2_assert_warn(sdp, qd->qd_change_sync);
 400                 error = bh_get(qd);
 401                 if (error) {
 402                         clear_bit(QDF_LOCKED, &qd->qd_flags);
 403                         slot_put(qd);
 404                         qd_put(qd);
 405                         return error;
 406                 }
 407         }
 408
 409         *qdp = qd;
 410
 411         return 0;
 412 }
 413
 414 static int qd_trylock(struct gfs2_quota_data *qd)
 415 {
 416         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 417
 418         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 419                 return 0;
 420
 421         spin_lock(&qd_lru_lock);
 422
 423         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 424             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
 425                 spin_unlock(&qd_lru_lock);
 426                 return 0;
 427         }
 428
 429         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 430
 431         set_bit(QDF_LOCKED, &qd->qd_flags);
 432         gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
 433         atomic_inc(&qd->qd_count);
 434         qd->qd_change_sync = qd->qd_change;
 435         gfs2_assert_warn(sdp, qd->qd_slot_count);
 436         qd->qd_slot_count++;
 437
 438         spin_unlock(&qd_lru_lock);
 439
 440         gfs2_assert_warn(sdp, qd->qd_change_sync);
 441         if (bh_get(qd)) {
 442                 clear_bit(QDF_LOCKED, &qd->qd_flags);
 443                 slot_put(qd);
 444                 qd_put(qd);
 445                 return 0;
 446         }
 447
 448         return 1;
 449 }
 450
 451 static void qd_unlock(struct gfs2_quota_data *qd)
 452 {
 453         gfs2_assert_warn(qd->qd_gl->gl_sbd,
 454                          test_bit(QDF_LOCKED, &qd->qd_flags));
 455         clear_bit(QDF_LOCKED, &qd->qd_flags);
 456         bh_put(qd);
 457         slot_put(qd);
 458         qd_put(qd);
 459 }
 460
 461 static int qdsb_get(struct gfs2_sbd *sdp, int user, u32 id,
 462                     struct gfs2_quota_data **qdp)
 463 {
 464         int error;
 465
 466         error = qd_get(sdp, user, id, qdp);
 467         if (error)
 468                 return error;
 469
 470         error = slot_get(*qdp);
 471         if (error)
 472                 goto fail;
 473
 474         error = bh_get(*qdp);
 475         if (error)
 476                 goto fail_slot;
 477
 478         return 0;
 479
 480 fail_slot:
 481         slot_put(*qdp);
 482 fail:
 483         qd_put(*qdp);
 484         return error;
 485 }
 486
 487 static void qdsb_put(struct gfs2_quota_data *qd)
 488 {
 489         bh_put(qd);
 490         slot_put(qd);
 491         qd_put(qd);
 492 }
 493
 494 int gfs2_quota_hold(struct gfs2_inode *ip, u32 uid, u32 gid)
 495 {
 496         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 497         struct gfs2_qadata *qa = ip->i_qadata;
 498         struct gfs2_quota_data **qd = qa->qa_qd;
 499         int error;
 500
 501         if (gfs2_assert_warn(sdp, !qa->qa_qd_num) ||
 502             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
 503                 return -EIO;
 504
 505         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 506                 return 0;
 507
 508         error = qdsb_get(sdp, QUOTA_USER, ip->i_inode.i_uid, qd);
 509         if (error)
 510                 goto out;
 511         qa->qa_qd_num++;
 512         qd++;
 513
 514         error = qdsb_get(sdp, QUOTA_GROUP, ip->i_inode.i_gid, qd);
 515         if (error)
 516                 goto out;
 517         qa->qa_qd_num++;
 518         qd++;
 519
 520         if (uid != NO_QUOTA_CHANGE && uid != ip->i_inode.i_uid) {
 521                 error = qdsb_get(sdp, QUOTA_USER, uid, qd);
 522                 if (error)
 523                         goto out;
 524                 qa->qa_qd_num++;
 525                 qd++;
 526         }
 527
 528         if (gid != NO_QUOTA_CHANGE && gid != ip->i_inode.i_gid) {
 529                 error = qdsb_get(sdp, QUOTA_GROUP, gid, qd);
 530                 if (error)
 531                         goto out;
 532                 qa->qa_qd_num++;
 533                 qd++;
 534         }
 535
 536 out:
 537         if (error)
 538                 gfs2_quota_unhold(ip);
 539         return error;
 540 }
 541
 542 void gfs2_quota_unhold(struct gfs2_inode *ip)
 543 {
 544         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 545         struct gfs2_qadata *qa = ip->i_qadata;
 546         unsigned int x;
 547
 548         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 549
 550         for (x = 0; x < qa->qa_qd_num; x++) {
 551                 qdsb_put(qa->qa_qd[x]);
 552                 qa->qa_qd[x] = NULL;
 553         }
 554         qa->qa_qd_num = 0;
 555 }
 556
 557 static int sort_qd(const void *a, const void *b)
 558 {
 559         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
 560         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
 561
 562         if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
 563             !test_bit(QDF_USER, &qd_b->qd_flags)) {
 564                 if (test_bit(QDF_USER, &qd_a->qd_flags))
 565                         return -1;
 566                 else
 567                         return 1;
 568         }
 569         if (qd_a->qd_id < qd_b->qd_id)
 570                 return -1;
 571         if (qd_a->qd_id > qd_b->qd_id)
 572                 return 1;
 573
 574         return 0;
 575 }
 576
 577 static void do_qc(struct gfs2_quota_data *qd, s64 change)
 578 {
 579         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 580         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 581         struct gfs2_quota_change *qc = qd->qd_bh_qc;
 582         s64 x;
 583
 584         mutex_lock(&sdp->sd_quota_mutex);
 585         gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
 586
 587         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
 588                 qc->qc_change = 0;
 589                 qc->qc_flags = 0;
 590                 if (test_bit(QDF_USER, &qd->qd_flags))
 591                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
 592                 qc->qc_id = cpu_to_be32(qd->qd_id);
 593         }
 594
 595         x = be64_to_cpu(qc->qc_change) + change;
 596         qc->qc_change = cpu_to_be64(x);
 597
 598         spin_lock(&qd_lru_lock);
 599         qd->qd_change = x;
 600         spin_unlock(&qd_lru_lock);
 601
 602         if (!x) {
 603                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
 604                 clear_bit(QDF_CHANGE, &qd->qd_flags);
 605                 qc->qc_flags = 0;
 606                 qc->qc_id = 0;
 607                 slot_put(qd);
 608                 qd_put(qd);
 609         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
 610                 qd_hold(qd);
 611                 slot_hold(qd);
 612         }
 613
 614         mutex_unlock(&sdp->sd_quota_mutex);
 615 }
 616
 617 /**
 618  * gfs2_adjust_quota - adjust record of current block usage
 619  * @ip: The quota inode
 620  * @loc: Offset of the entry in the quota file
 621  * @change: The amount of usage change to record
 622  * @qd: The quota data
 623  * @fdq: The updated limits to record
 624  *
 625  * This function was mostly borrowed from gfs2_block_truncate_page which was
 626  * in turn mostly borrowed from ext3
 627  *
 628  * Returns: 0 or -ve on error
 629  */
 630
 631 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 632                              s64 change, struct gfs2_quota_data *qd,
 633                              struct fs_disk_quota *fdq)
 634 {
 635         struct inode *inode = &ip->i_inode;
 636         struct gfs2_sbd *sdp = GFS2_SB(inode);
 637         struct address_space *mapping = inode->i_mapping;
 638         unsigned long index = loc >> PAGE_CACHE_SHIFT;
 639         unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
 640         unsigned blocksize, iblock, pos;
 641         struct buffer_head *bh;
 642         struct page *page;
 643         void *kaddr, *ptr;
 644         struct gfs2_quota q, *qp;
 645         int err, nbytes;
 646         u64 size;
 647
 648         if (gfs2_is_stuffed(ip)) {
 649                 err = gfs2_unstuff_dinode(ip, NULL);
 650                 if (err)
 651                         return err;
 652         }
 653
 654         memset(&q, 0, sizeof(struct gfs2_quota));
 655         err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
 656         if (err < 0)
 657                 return err;
 658
 659         err = -EIO;
 660         qp = &q;
 661         qp->qu_value = be64_to_cpu(qp->qu_value);
 662         qp->qu_value += change;
 663         qp->qu_value = cpu_to_be64(qp->qu_value);
 664         qd->qd_qb.qb_value = qp->qu_value;
 665         if (fdq) {
 666                 if (fdq->d_fieldmask & FS_DQ_BSOFT) {
 667                         qp->qu_warn = cpu_to_be64(fdq->d_blk_softlimit >> sdp->sd_fsb2bb_shift);
 668                         qd->qd_qb.qb_warn = qp->qu_warn;
 669                 }
 670                 if (fdq->d_fieldmask & FS_DQ_BHARD) {
 671                         qp->qu_limit = cpu_to_be64(fdq->d_blk_hardlimit >> sdp->sd_fsb2bb_shift);
 672                         qd->qd_qb.qb_limit = qp->qu_limit;
 673                 }
 674                 if (fdq->d_fieldmask & FS_DQ_BCOUNT) {
 675                         qp->qu_value = cpu_to_be64(fdq->d_bcount >> sdp->sd_fsb2bb_shift);
 676                         qd->qd_qb.qb_value = qp->qu_value;
 677                 }
 678         }
 679
 680         /* Write the quota into the quota file on disk */
 681         ptr = qp;
 682         nbytes = sizeof(struct gfs2_quota);
 683 get_a_page:
 684         page = find_or_create_page(mapping, index, GFP_NOFS);
 685         if (!page)
 686                 return -ENOMEM;
 687
 688         blocksize = inode->i_sb->s_blocksize;
 689         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
 690
 691         if (!page_has_buffers(page))
 692                 create_empty_buffers(page, blocksize, 0);
 693
 694         bh = page_buffers(page);
 695         pos = blocksize;
 696         while (offset >= pos) {
 697                 bh = bh->b_this_page;
 698                 iblock++;
 699                 pos += blocksize;
 700         }
 701
 702         if (!buffer_mapped(bh)) {
 703                 gfs2_block_map(inode, iblock, bh, 1);
 704                 if (!buffer_mapped(bh))
 705                         goto unlock_out;
 706                 /* If it's a newly allocated disk block for quota, zero it */
 707                 if (buffer_new(bh))
 708                         zero_user(page, pos - blocksize, bh->b_size);
 709         }
 710
 711         if (PageUptodate(page))
 712                 set_buffer_uptodate(bh);
 713
 714         if (!buffer_uptodate(bh)) {
 715                 ll_rw_block(READ | REQ_META, 1, &bh);
 716                 wait_on_buffer(bh);
 717                 if (!buffer_uptodate(bh))
 718                         goto unlock_out;
 719         }
 720
 721         gfs2_trans_add_bh(ip->i_gl, bh, 0);
 722
 723         kaddr = kmap_atomic(page);
 724         if (offset + sizeof(struct gfs2_quota) > PAGE_CACHE_SIZE)
 725                 nbytes = PAGE_CACHE_SIZE - offset;
 726         memcpy(kaddr + offset, ptr, nbytes);
 727         flush_dcache_page(page);
 728         kunmap_atomic(kaddr);
 729         unlock_page(page);
 730         page_cache_release(page);
 731
 732         /* If quota straddles page boundary, we need to update the rest of the
 733          * quota at the beginning of the next page */
 734         if ((offset + sizeof(struct gfs2_quota)) > PAGE_CACHE_SIZE) {
 735                 ptr = ptr + nbytes;
 736                 nbytes = sizeof(struct gfs2_quota) - nbytes;
 737                 offset = 0;
 738                 index++;
 739                 goto get_a_page;
 740         }
 741
 742         size = loc + sizeof(struct gfs2_quota);
 743         if (size > inode->i_size)
 744                 i_size_write(inode, size);
 745         inode->i_mtime = inode->i_atime = CURRENT_TIME;
 746         mark_inode_dirty(inode);
 747         return 0;
 748
 749 unlock_out:
 750         unlock_page(page);
 751         page_cache_release(page);
 752         return err;
 753 }
 754
 755 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 756 {
 757         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
 758         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 759         unsigned int data_blocks, ind_blocks;
 760         struct gfs2_holder *ghs, i_gh;
 761         unsigned int qx, x;
 762         struct gfs2_quota_data *qd;
 763         loff_t offset;
 764         unsigned int nalloc = 0, blocks;
 765         int error;
 766
 767         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 768                               &data_blocks, &ind_blocks);
 769
 770         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
 771         if (!ghs)
 772                 return -ENOMEM;
 773
 774         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 775         mutex_lock_nested(&ip->i_inode.i_mutex, I_MUTEX_QUOTA);
 776         for (qx = 0; qx < num_qd; qx++) {
 777                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
 778                                            GL_NOCACHE, &ghs[qx]);
 779                 if (error)
 780                         goto out;
 781         }
 782
 783         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 784         if (error)
 785                 goto out;
 786
 787         for (x = 0; x < num_qd; x++) {
 788                 offset = qd2offset(qda[x]);
 789                 if (gfs2_write_alloc_required(ip, offset,
 790                                               sizeof(struct gfs2_quota)))
 791                         nalloc++;
 792         }
 793
 794         /*
 795          * 1 blk for unstuffing inode if stuffed. We add this extra
 796          * block to the reservation unconditionally. If the inode
 797          * doesn't need unstuffing, the block will be released to the
 798          * rgrp since it won't be allocated during the transaction
 799          */
 800         /* +3 in the end for unstuffing block, inode size update block
 801          * and another block in case quota straddles page boundary and
 802          * two blocks need to be updated instead of 1 */
 803         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
 804
 805         error = gfs2_inplace_reserve(ip, 1 +
 806                                      (nalloc * (data_blocks + ind_blocks)));
 807         if (error)
 808                 goto out_alloc;
 809
 810         if (nalloc)
 811                 blocks += gfs2_rg_blocks(ip) + nalloc * ind_blocks + RES_STATFS;
 812
 813         error = gfs2_trans_begin(sdp, blocks, 0);
 814         if (error)
 815                 goto out_ipres;
 816
 817         for (x = 0; x < num_qd; x++) {
 818                 qd = qda[x];
 819                 offset = qd2offset(qd);
 820                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
 821                 if (error)
 822                         goto out_end_trans;
 823
 824                 do_qc(qd, -qd->qd_change_sync);
 825                 set_bit(QDF_REFRESH, &qd->qd_flags);
 826         }
 827
 828         error = 0;
 829
 830 out_end_trans:
 831         gfs2_trans_end(sdp);
 832 out_ipres:
 833         gfs2_inplace_release(ip);
 834 out_alloc:
 835         gfs2_glock_dq_uninit(&i_gh);
 836 out:
 837         while (qx--)
 838                 gfs2_glock_dq_uninit(&ghs[qx]);
 839         mutex_unlock(&ip->i_inode.i_mutex);
 840         kfree(ghs);
 841         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
 842         return error;
 843 }
 844
 845 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
 846 {
 847         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 848         struct gfs2_quota q;
 849         struct gfs2_quota_lvb *qlvb;
 850         loff_t pos;
 851         int error;
 852
 853         memset(&q, 0, sizeof(struct gfs2_quota));
 854         pos = qd2offset(qd);
 855         error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
 856         if (error < 0)
 857                 return error;
 858
 859         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 860         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
 861         qlvb->__pad = 0;
 862         qlvb->qb_limit = q.qu_limit;
 863         qlvb->qb_warn = q.qu_warn;
 864         qlvb->qb_value = q.qu_value;
 865         qd->qd_qb = *qlvb;
 866
 867         return 0;
 868 }
 869
 870 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 871                     struct gfs2_holder *q_gh)
 872 {
 873         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 874         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 875         struct gfs2_holder i_gh;
 876         int error;
 877
 878 restart:
 879         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 880         if (error)
 881                 return error;
 882
 883         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 884
 885         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
 886                 gfs2_glock_dq_uninit(q_gh);
 887                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
 888                                            GL_NOCACHE, q_gh);
 889                 if (error)
 890                         return error;
 891
 892                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
 893                 if (error)
 894                         goto fail;
 895
 896                 error = update_qd(sdp, qd);
 897                 if (error)
 898                         goto fail_gunlock;
 899
 900                 gfs2_glock_dq_uninit(&i_gh);
 901                 gfs2_glock_dq_uninit(q_gh);
 902                 force_refresh = 0;
 903                 goto restart;
 904         }
 905
 906         return 0;
 907
 908 fail_gunlock:
 909         gfs2_glock_dq_uninit(&i_gh);
 910 fail:
 911         gfs2_glock_dq_uninit(q_gh);
 912         return error;
 913 }
 914
 915 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
 916 {
 917         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 918         struct gfs2_qadata *qa = ip->i_qadata;
 919         struct gfs2_quota_data *qd;
 920         unsigned int x;
 921         int error = 0;
 922
 923         error = gfs2_quota_hold(ip, uid, gid);
 924         if (error)
 925                 return error;
 926
 927         if (capable(CAP_SYS_RESOURCE) ||
 928             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 929                 return 0;
 930
 931         sort(qa->qa_qd, qa->qa_qd_num, sizeof(struct gfs2_quota_data *),
 932              sort_qd, NULL);
 933
 934         for (x = 0; x < qa->qa_qd_num; x++) {
 935                 int force = NO_FORCE;
 936                 qd = qa->qa_qd[x];
 937                 if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
 938                         force = FORCE;
 939                 error = do_glock(qd, force, &qa->qa_qd_ghs[x]);
 940                 if (error)
 941                         break;
 942         }
 943
 944         if (!error)
 945                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
 946         else {
 947                 while (x--)
 948                         gfs2_glock_dq_uninit(&qa->qa_qd_ghs[x]);
 949                 gfs2_quota_unhold(ip);
 950         }
 951
 952         return error;
 953 }
 954
 955 static int need_sync(struct gfs2_quota_data *qd)
 956 {
 957         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 958         struct gfs2_tune *gt = &sdp->sd_tune;
 959         s64 value;
 960         unsigned int num, den;
 961         int do_sync = 1;
 962
 963         if (!qd->qd_qb.qb_limit)
 964                 return 0;
 965
 966         spin_lock(&qd_lru_lock);
 967         value = qd->qd_change;
 968         spin_unlock(&qd_lru_lock);
 969
 970         spin_lock(&gt->gt_spin);
 971         num = gt->gt_quota_scale_num;
 972         den = gt->gt_quota_scale_den;
 973         spin_unlock(&gt->gt_spin);
 974
 975         if (value < 0)
 976                 do_sync = 0;
 977         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
 978                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 979                 do_sync = 0;
 980         else {
 981                 value *= gfs2_jindex_size(sdp) * num;
 982                 value = div_s64(value, den);
 983                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
 984                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 985                         do_sync = 0;
 986         }
 987
 988         return do_sync;
 989 }
 990
 991 void gfs2_quota_unlock(struct gfs2_inode *ip)
 992 {
 993         struct gfs2_qadata *qa = ip->i_qadata;
 994         struct gfs2_quota_data *qda[4];
 995         unsigned int count = 0;
 996         unsigned int x;
 997
 998         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
 999                 goto out;
1000
1001         for (x = 0; x < qa->qa_qd_num; x++) {
1002                 struct gfs2_quota_data *qd;
1003                 int sync;
1004
1005                 qd = qa->qa_qd[x];
1006                 sync = need_sync(qd);
1007
1008                 gfs2_glock_dq_uninit(&qa->qa_qd_ghs[x]);
1009
1010                 if (sync && qd_trylock(qd))
1011                         qda[count++] = qd;
1012         }
1013
1014         if (count) {
1015                 do_sync(count, qda);
1016                 for (x = 0; x < count; x++)
1017                         qd_unlock(qda[x]);
1018         }
1019
1020 out:
1021         gfs2_quota_unhold(ip);
1022 }
1023
1024 #define MAX_LINE 256
1025
1026 static int print_message(struct gfs2_quota_data *qd, char *type)
1027 {
1028         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1029
1030         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\n",
1031                sdp->sd_fsname, type,
1032                (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
1033                qd->qd_id);
1034
1035         return 0;
1036 }
1037
1038 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
1039 {
1040         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1041         struct gfs2_qadata *qa = ip->i_qadata;
1042         struct gfs2_quota_data *qd;
1043         s64 value;
1044         unsigned int x;
1045         int error = 0;
1046
1047         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1048                 return 0;
1049
1050         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1051                 return 0;
1052
1053         for (x = 0; x < qa->qa_qd_num; x++) {
1054                 qd = qa->qa_qd[x];
1055
1056                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1057                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
1058                         continue;
1059
1060                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1061                 spin_lock(&qd_lru_lock);
1062                 value += qd->qd_change;
1063                 spin_unlock(&qd_lru_lock);
1064
1065                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
1066                         print_message(qd, "exceeded");
1067                         quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1068                                            USRQUOTA : GRPQUOTA, qd->qd_id,
1069                                            sdp->sd_vfs->s_dev, QUOTA_NL_BHARDWARN);
1070
1071                         error = -EDQUOT;
1072                         break;
1073                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
1074                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
1075                            time_after_eq(jiffies, qd->qd_last_warn +
1076                                          gfs2_tune_get(sdp,
1077                                                 gt_quota_warn_period) * HZ)) {
1078                         quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1079                                            USRQUOTA : GRPQUOTA, qd->qd_id,
1080                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1081                         error = print_message(qd, "warning");
1082                         qd->qd_last_warn = jiffies;
1083                 }
1084         }
1085
1086         return error;
1087 }
1088
1089 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1090                        u32 uid, u32 gid)
1091 {
1092         struct gfs2_qadata *qa = ip->i_qadata;
1093         struct gfs2_quota_data *qd;
1094         unsigned int x;
1095
1096         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1097                 return;
1098         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1099                 return;
1100
1101         for (x = 0; x < qa->qa_qd_num; x++) {
1102                 qd = qa->qa_qd[x];
1103
1104                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1105                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
1106                         do_qc(qd, change);
1107                 }
1108         }
1109 }
1110
1111 int gfs2_quota_sync(struct super_block *sb, int type, int wait)
1112 {
1113         struct gfs2_sbd *sdp = sb->s_fs_info;
1114         struct gfs2_quota_data **qda;
1115         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1116         unsigned int num_qd;
1117         unsigned int x;
1118         int error = 0;
1119
1120         sdp->sd_quota_sync_gen++;
1121
1122         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1123         if (!qda)
1124                 return -ENOMEM;
1125
1126         do {
1127                 num_qd = 0;
1128
1129                 for (;;) {
1130                         error = qd_fish(sdp, qda + num_qd);
1131                         if (error || !qda[num_qd])
1132                                 break;
1133                         if (++num_qd == max_qd)
1134                                 break;
1135                 }
1136
1137                 if (num_qd) {
1138                         if (!error)
1139                                 error = do_sync(num_qd, qda);
1140                         if (!error)
1141                                 for (x = 0; x < num_qd; x++)
1142                                         qda[x]->qd_sync_gen =
1143                                                 sdp->sd_quota_sync_gen;
1144
1145                         for (x = 0; x < num_qd; x++)
1146                                 qd_unlock(qda[x]);
1147                 }
1148         } while (!error && num_qd == max_qd);
1149
1150         kfree(qda);
1151
1152         return error;
1153 }
1154
1155 static int gfs2_quota_sync_timeo(struct super_block *sb, int type)
1156 {
1157         return gfs2_quota_sync(sb, type, 0);
1158 }
1159
1160 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1161 {
1162         struct gfs2_quota_data *qd;
1163         struct gfs2_holder q_gh;
1164         int error;
1165
1166         error = qd_get(sdp, user, id, &qd);
1167         if (error)
1168                 return error;
1169
1170         error = do_glock(qd, FORCE, &q_gh);
1171         if (!error)
1172                 gfs2_glock_dq_uninit(&q_gh);
1173
1174         qd_put(qd);
1175         return error;
1176 }
1177
1178 static void gfs2_quota_change_in(struct gfs2_quota_change_host *qc, const void *buf)
1179 {
1180         const struct gfs2_quota_change *str = buf;
1181
1182         qc->qc_change = be64_to_cpu(str->qc_change);
1183         qc->qc_flags = be32_to_cpu(str->qc_flags);
1184         qc->qc_id = be32_to_cpu(str->qc_id);
1185 }
1186
1187 int gfs2_quota_init(struct gfs2_sbd *sdp)
1188 {
1189         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1190         u64 size = i_size_read(sdp->sd_qc_inode);
1191         unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1192         unsigned int x, slot = 0;
1193         unsigned int found = 0;
1194         u64 dblock;
1195         u32 extlen = 0;
1196         int error;
1197
1198         if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1199                 return -EIO;
1200
1201         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1202         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1203
1204         error = -ENOMEM;
1205
1206         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1207                                        sizeof(unsigned char *), GFP_NOFS);
1208         if (!sdp->sd_quota_bitmap)
1209                 return error;
1210
1211         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1212                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_NOFS);
1213                 if (!sdp->sd_quota_bitmap[x])
1214                         goto fail;
1215         }
1216
1217         for (x = 0; x < blocks; x++) {
1218                 struct buffer_head *bh;
1219                 unsigned int y;
1220
1221                 if (!extlen) {
1222                         int new = 0;
1223                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1224                         if (error)
1225                                 goto fail;
1226                 }
1227                 error = -EIO;
1228                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1229                 if (!bh)
1230                         goto fail;
1231                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1232                         brelse(bh);
1233                         goto fail;
1234                 }
1235
1236                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1237                      y++, slot++) {
1238                         struct gfs2_quota_change_host qc;
1239                         struct gfs2_quota_data *qd;
1240
1241                         gfs2_quota_change_in(&qc, bh->b_data +
1242                                           sizeof(struct gfs2_meta_header) +
1243                                           y * sizeof(struct gfs2_quota_change));
1244                         if (!qc.qc_change)
1245                                 continue;
1246
1247                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1248                                          qc.qc_id, &qd);
1249                         if (error) {
1250                                 brelse(bh);
1251                                 goto fail;
1252                         }
1253
1254                         set_bit(QDF_CHANGE, &qd->qd_flags);
1255                         qd->qd_change = qc.qc_change;
1256                         qd->qd_slot = slot;
1257                         qd->qd_slot_count = 1;
1258
1259                         spin_lock(&qd_lru_lock);
1260                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1261                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1262                         atomic_inc(&sdp->sd_quota_count);
1263                         spin_unlock(&qd_lru_lock);
1264
1265                         found++;
1266                 }
1267
1268                 brelse(bh);
1269                 dblock++;
1270                 extlen--;
1271         }
1272
1273         if (found)
1274                 fs_info(sdp, "found %u quota changes\n", found);
1275
1276         return 0;
1277
1278 fail:
1279         gfs2_quota_cleanup(sdp);
1280         return error;
1281 }
1282
1283 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1284 {
1285         struct list_head *head = &sdp->sd_quota_list;
1286         struct gfs2_quota_data *qd;
1287         unsigned int x;
1288
1289         spin_lock(&qd_lru_lock);
1290         while (!list_empty(head)) {
1291                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1292
1293                 if (atomic_read(&qd->qd_count) > 1 ||
1294                     (atomic_read(&qd->qd_count) &&
1295                      !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1296                         list_move(&qd->qd_list, head);
1297                         spin_unlock(&qd_lru_lock);
1298                         schedule();
1299                         spin_lock(&qd_lru_lock);
1300                         continue;
1301                 }
1302
1303                 list_del(&qd->qd_list);
1304                 /* Also remove if this qd exists in the reclaim list */
1305                 if (!list_empty(&qd->qd_reclaim)) {
1306                         list_del_init(&qd->qd_reclaim);
1307                         atomic_dec(&qd_lru_count);
1308                 }
1309                 atomic_dec(&sdp->sd_quota_count);
1310                 spin_unlock(&qd_lru_lock);
1311
1312                 if (!atomic_read(&qd->qd_count)) {
1313                         gfs2_assert_warn(sdp, !qd->qd_change);
1314                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1315                 } else
1316                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1317                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1318
1319                 gfs2_glock_put(qd->qd_gl);
1320                 kmem_cache_free(gfs2_quotad_cachep, qd);
1321
1322                 spin_lock(&qd_lru_lock);
1323         }
1324         spin_unlock(&qd_lru_lock);
1325
1326         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1327
1328         if (sdp->sd_quota_bitmap) {
1329                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1330                         kfree(sdp->sd_quota_bitmap[x]);
1331                 kfree(sdp->sd_quota_bitmap);
1332         }
1333 }
1334
1335 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1336 {
1337         if (error == 0 || error == -EROFS)
1338                 return;
1339         if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1340                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1341 }
1342
1343 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1344                                int (*fxn)(struct super_block *sb, int type),
1345                                unsigned long t, unsigned long *timeo,
1346                                unsigned int *new_timeo)
1347 {
1348         if (t >= *timeo) {
1349                 int error = fxn(sdp->sd_vfs, 0);
1350                 quotad_error(sdp, msg, error);
1351                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1352         } else {
1353                 *timeo -= t;
1354         }
1355 }
1356
1357 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1358 {
1359         struct gfs2_inode *ip;
1360
1361         while(1) {
1362                 ip = NULL;
1363                 spin_lock(&sdp->sd_trunc_lock);
1364                 if (!list_empty(&sdp->sd_trunc_list)) {
1365                         ip = list_entry(sdp->sd_trunc_list.next,
1366                                         struct gfs2_inode, i_trunc_list);
1367                         list_del_init(&ip->i_trunc_list);
1368                 }
1369                 spin_unlock(&sdp->sd_trunc_lock);
1370                 if (ip == NULL)
1371                         return;
1372                 gfs2_glock_finish_truncate(ip);
1373         }
1374 }
1375
1376 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1377         if (!sdp->sd_statfs_force_sync) {
1378                 sdp->sd_statfs_force_sync = 1;
1379                 wake_up(&sdp->sd_quota_wait);
1380         }
1381 }
1382
1383
1384 /**
1385  * gfs2_quotad - Write cached quota changes into the quota file
1386  * @sdp: Pointer to GFS2 superblock
1387  *
1388  */
1389
1390 int gfs2_quotad(void *data)
1391 {
1392         struct gfs2_sbd *sdp = data;
1393         struct gfs2_tune *tune = &sdp->sd_tune;
1394         unsigned long statfs_timeo = 0;
1395         unsigned long quotad_timeo = 0;
1396         unsigned long t = 0;
1397         DEFINE_WAIT(wait);
1398         int empty;
1399
1400         while (!kthread_should_stop()) {
1401
1402                 /* Update the master statfs file */
1403                 if (sdp->sd_statfs_force_sync) {
1404                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1405                         quotad_error(sdp, "statfs", error);
1406                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1407                 }
1408                 else
1409                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1410                                            &statfs_timeo,
1411                                            &tune->gt_statfs_quantum);
1412
1413                 /* Update quota file */
1414                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync_timeo, t,
1415                                    &quotad_timeo, &tune->gt_quota_quantum);
1416
1417                 /* Check for & recover partially truncated inodes */
1418                 quotad_check_trunc_list(sdp);
1419
1420                 try_to_freeze();
1421
1422                 t = min(quotad_timeo, statfs_timeo);
1423
1424                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1425                 spin_lock(&sdp->sd_trunc_lock);
1426                 empty = list_empty(&sdp->sd_trunc_list);
1427                 spin_unlock(&sdp->sd_trunc_lock);
1428                 if (empty && !sdp->sd_statfs_force_sync)
1429                         t -= schedule_timeout(t);
1430                 else
1431                         t = 0;
1432                 finish_wait(&sdp->sd_quota_wait, &wait);
1433         }
1434
1435         return 0;
1436 }
1437
1438 static int gfs2_quota_get_xstate(struct super_block *sb,
1439                                  struct fs_quota_stat *fqs)
1440 {
1441         struct gfs2_sbd *sdp = sb->s_fs_info;
1442
1443         memset(fqs, 0, sizeof(struct fs_quota_stat));
1444         fqs->qs_version = FS_QSTAT_VERSION;
1445
1446         switch (sdp->sd_args.ar_quota) {
1447         case GFS2_QUOTA_ON:
1448                 fqs->qs_flags |= (FS_QUOTA_UDQ_ENFD | FS_QUOTA_GDQ_ENFD);
1449                 /*FALLTHRU*/
1450         case GFS2_QUOTA_ACCOUNT:
1451                 fqs->qs_flags |= (FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT);
1452                 break;
1453         case GFS2_QUOTA_OFF:
1454                 break;
1455         }
1456
1457         if (sdp->sd_quota_inode) {
1458                 fqs->qs_uquota.qfs_ino = GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1459                 fqs->qs_uquota.qfs_nblks = sdp->sd_quota_inode->i_blocks;
1460         }
1461         fqs->qs_uquota.qfs_nextents = 1; /* unsupported */
1462         fqs->qs_gquota = fqs->qs_uquota; /* its the same inode in both cases */
1463         fqs->qs_incoredqs = atomic_read(&qd_lru_count);
1464         return 0;
1465 }
1466
1467 static int gfs2_get_dqblk(struct super_block *sb, int type, qid_t id,
1468                           struct fs_disk_quota *fdq)
1469 {
1470         struct gfs2_sbd *sdp = sb->s_fs_info;
1471         struct gfs2_quota_lvb *qlvb;
1472         struct gfs2_quota_data *qd;
1473         struct gfs2_holder q_gh;
1474         int error;
1475
1476         memset(fdq, 0, sizeof(struct fs_disk_quota));
1477
1478         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1479                 return -ESRCH; /* Crazy XFS error code */
1480
1481         if (type == USRQUOTA)
1482                 type = QUOTA_USER;
1483         else if (type == GRPQUOTA)
1484                 type = QUOTA_GROUP;
1485         else
1486                 return -EINVAL;
1487
1488         error = qd_get(sdp, type, id, &qd);
1489         if (error)
1490                 return error;
1491         error = do_glock(qd, FORCE, &q_gh);
1492         if (error)
1493                 goto out;
1494
1495         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
1496         fdq->d_version = FS_DQUOT_VERSION;
1497         fdq->d_flags = (type == QUOTA_USER) ? FS_USER_QUOTA : FS_GROUP_QUOTA;
1498         fdq->d_id = id;
1499         fdq->d_blk_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_fsb2bb_shift;
1500         fdq->d_blk_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_fsb2bb_shift;
1501         fdq->d_bcount = be64_to_cpu(qlvb->qb_value) << sdp->sd_fsb2bb_shift;
1502
1503         gfs2_glock_dq_uninit(&q_gh);
1504 out:
1505         qd_put(qd);
1506         return error;
1507 }
1508
1509 /* GFS2 only supports a subset of the XFS fields */
1510 #define GFS2_FIELDMASK (FS_DQ_BSOFT|FS_DQ_BHARD|FS_DQ_BCOUNT)
1511
1512 static int gfs2_set_dqblk(struct super_block *sb, int type, qid_t id,
1513                           struct fs_disk_quota *fdq)
1514 {
1515         struct gfs2_sbd *sdp = sb->s_fs_info;
1516         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1517         struct gfs2_quota_data *qd;
1518         struct gfs2_holder q_gh, i_gh;
1519         unsigned int data_blocks, ind_blocks;
1520         unsigned int blocks = 0;
1521         int alloc_required;
1522         loff_t offset;
1523         int error;
1524
1525         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1526                 return -ESRCH; /* Crazy XFS error code */
1527
1528         switch(type) {
1529         case USRQUOTA:
1530                 type = QUOTA_USER;
1531                 if (fdq->d_flags != FS_USER_QUOTA)
1532                         return -EINVAL;
1533                 break;
1534         case GRPQUOTA:
1535                 type = QUOTA_GROUP;
1536                 if (fdq->d_flags != FS_GROUP_QUOTA)
1537                         return -EINVAL;
1538                 break;
1539         default:
1540                 return -EINVAL;
1541         }
1542
1543         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1544                 return -EINVAL;
1545         if (fdq->d_id != id)
1546                 return -EINVAL;
1547
1548         error = qd_get(sdp, type, id, &qd);
1549         if (error)
1550                 return error;
1551
1552         mutex_lock(&ip->i_inode.i_mutex);
1553         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1554         if (error)
1555                 goto out_put;
1556         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1557         if (error)
1558                 goto out_q;
1559
1560         /* Check for existing entry, if none then alloc new blocks */
1561         error = update_qd(sdp, qd);
1562         if (error)
1563                 goto out_i;
1564
1565         /* If nothing has changed, this is a no-op */
1566         if ((fdq->d_fieldmask & FS_DQ_BSOFT) &&
1567             ((fdq->d_blk_softlimit >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1568                 fdq->d_fieldmask ^= FS_DQ_BSOFT;
1569
1570         if ((fdq->d_fieldmask & FS_DQ_BHARD) &&
1571             ((fdq->d_blk_hardlimit >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1572                 fdq->d_fieldmask ^= FS_DQ_BHARD;
1573
1574         if ((fdq->d_fieldmask & FS_DQ_BCOUNT) &&
1575             ((fdq->d_bcount >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1576                 fdq->d_fieldmask ^= FS_DQ_BCOUNT;
1577
1578         if (fdq->d_fieldmask == 0)
1579                 goto out_i;
1580
1581         offset = qd2offset(qd);
1582         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1583         if (gfs2_is_stuffed(ip))
1584                 alloc_required = 1;
1585         if (alloc_required) {
1586                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1587                                        &data_blocks, &ind_blocks);
1588                 blocks = 1 + data_blocks + ind_blocks;
1589                 error = gfs2_inplace_reserve(ip, blocks);
1590                 if (error)
1591                         goto out_i;
1592                 blocks += gfs2_rg_blocks(ip);
1593         }
1594
1595         /* Some quotas span block boundaries and can update two blocks,
1596            adding an extra block to the transaction to handle such quotas */
1597         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1598         if (error)
1599                 goto out_release;
1600
1601         /* Apply changes */
1602         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1603
1604         gfs2_trans_end(sdp);
1605 out_release:
1606         if (alloc_required)
1607                 gfs2_inplace_release(ip);
1608 out_i:
1609         gfs2_glock_dq_uninit(&i_gh);
1610 out_q:
1611         gfs2_glock_dq_uninit(&q_gh);
1612 out_put:
1613         mutex_unlock(&ip->i_inode.i_mutex);
1614         qd_put(qd);
1615         return error;
1616 }
1617
1618 const struct quotactl_ops gfs2_quotactl_ops = {
1619         .quota_sync     = gfs2_quota_sync,
1620         .get_xstate     = gfs2_quota_get_xstate,
1621         .get_dqblk      = gfs2_get_dqblk,
1622         .set_dqblk      = gfs2_set_dqblk,
1623 };