fs/gfs2/quota.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2005 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 v.2.
   8  */
   9
  10 /*
  11  * Quota change tags are associated with each transaction that allocates or
  12  * deallocates space.  Those changes are accumulated locally to each node (in a
  13  * per-node file) and then are periodically synced to the quota file.  This
  14  * avoids the bottleneck of constantly touching the quota file, but introduces
  15  * fuzziness in the current usage value of IDs that are being used on different
  16  * nodes in the cluster simultaneously.  So, it is possible for a user on
  17  * multiple nodes to overrun their quota, but that overrun is controlable.
  18  * Since quota tags are part of transactions, there is no need to a quota check
  19  * program to be run on node crashes or anything like that.
  20  *
  21  * There are couple of knobs that let the administrator manage the quota
  22  * fuzziness.  "quota_quantum" sets the maximum time a quota change can be
  23  * sitting on one node before being synced to the quota file.  (The default is
  24  * 60 seconds.)  Another knob, "quota_scale" controls how quickly the frequency
  25  * of quota file syncs increases as the user moves closer to their limit.  The
  26  * more frequent the syncs, the more accurate the quota enforcement, but that
  27  * means that there is more contention between the nodes for the quota file.
  28  * The default value is one.  This sets the maximum theoretical quota overrun
  29  * (with infinite node with infinite bandwidth) to twice the user's limit.  (In
  30  * practice, the maximum overrun you see should be much less.)  A "quota_scale"
  31  * number greater than one makes quota syncs more frequent and reduces the
  32  * maximum overrun.  Numbers less than one (but greater than zero) make quota
  33  * syncs less frequent.
  34  *
  35  * GFS quotas also use per-ID Lock Value Blocks (LVBs) to cache the contents of
  36  * the quota file, so it is not being constantly read.
  37  */
  38
  39 #include <linux/sched.h>
  40 #include <linux/slab.h>
  41 #include <linux/spinlock.h>
  42 #include <linux/completion.h>
  43 #include <linux/buffer_head.h>
  44 #include <linux/tty.h>
  45 #include <linux/sort.h>
  46 #include <linux/fs.h>
  47 #include <asm/semaphore.h>
  48
  49 #include "gfs2.h"
  50 #include "bmap.h"
  51 #include "glock.h"
  52 #include "glops.h"
  53 #include "log.h"
  54 #include "meta_io.h"
  55 #include "quota.h"
  56 #include "rgrp.h"
  57 #include "super.h"
  58 #include "trans.h"
  59 #include "inode.h"
  60 #include "ops_file.h"
  61 #include "ops_address.h"
  62
  63 #define QUOTA_USER 1
  64 #define QUOTA_GROUP 0
  65
  66 static uint64_t qd2offset(struct gfs2_quota_data *qd)
  67 {
  68         uint64_t offset;
  69
  70         offset = 2 * (uint64_t)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
  71         offset *= sizeof(struct gfs2_quota);
  72
  73         return offset;
  74 }
  75
  76 static int qd_alloc(struct gfs2_sbd *sdp, int user, uint32_t id,
  77                     struct gfs2_quota_data **qdp)
  78 {
  79         struct gfs2_quota_data *qd;
  80         int error;
  81
  82         qd = kzalloc(sizeof(struct gfs2_quota_data), GFP_KERNEL);
  83         if (!qd)
  84                 return -ENOMEM;
  85
  86         qd->qd_count = 1;
  87         qd->qd_id = id;
  88         if (user)
  89                 set_bit(QDF_USER, &qd->qd_flags);
  90         qd->qd_slot = -1;
  91
  92         error = gfs2_glock_get(sdp, 2 * (uint64_t)id + !user,
  93                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
  94         if (error)
  95                 goto fail;
  96
  97         error = gfs2_lvb_hold(qd->qd_gl);
  98         gfs2_glock_put(qd->qd_gl);
  99         if (error)
 100                 goto fail;
 101
 102         *qdp = qd;
 103
 104         return 0;
 105
 106  fail:
 107         kfree(qd);
 108         return error;
 109 }
 110
 111 static int qd_get(struct gfs2_sbd *sdp, int user, uint32_t id, int create,
 112                   struct gfs2_quota_data **qdp)
 113 {
 114         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
 115         int error, found;
 116
 117         *qdp = NULL;
 118
 119         for (;;) {
 120                 found = 0;
 121                 spin_lock(&sdp->sd_quota_spin);
 122                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 123                         if (qd->qd_id == id &&
 124                             !test_bit(QDF_USER, &qd->qd_flags) == !user) {
 125                                 qd->qd_count++;
 126                                 found = 1;
 127                                 break;
 128                         }
 129                 }
 130
 131                 if (!found)
 132                         qd = NULL;
 133
 134                 if (!qd && new_qd) {
 135                         qd = new_qd;
 136                         list_add(&qd->qd_list, &sdp->sd_quota_list);
 137                         atomic_inc(&sdp->sd_quota_count);
 138                         new_qd = NULL;
 139                 }
 140
 141                 spin_unlock(&sdp->sd_quota_spin);
 142
 143                 if (qd || !create) {
 144                         if (new_qd) {
 145                                 gfs2_lvb_unhold(new_qd->qd_gl);
 146                                 kfree(new_qd);
 147                         }
 148                         *qdp = qd;
 149                         return 0;
 150                 }
 151
 152                 error = qd_alloc(sdp, user, id, &new_qd);
 153                 if (error)
 154                         return error;
 155         }
 156 }
 157
 158 static void qd_hold(struct gfs2_quota_data *qd)
 159 {
 160         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 161
 162         spin_lock(&sdp->sd_quota_spin);
 163         gfs2_assert(sdp, qd->qd_count);
 164         qd->qd_count++;
 165         spin_unlock(&sdp->sd_quota_spin);
 166 }
 167
 168 static void qd_put(struct gfs2_quota_data *qd)
 169 {
 170         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 171         spin_lock(&sdp->sd_quota_spin);
 172         gfs2_assert(sdp, qd->qd_count);
 173         if (!--qd->qd_count)
 174                 qd->qd_last_touched = jiffies;
 175         spin_unlock(&sdp->sd_quota_spin);
 176 }
 177
 178 static int slot_get(struct gfs2_quota_data *qd)
 179 {
 180         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 181         unsigned int c, o = 0, b;
 182         unsigned char byte = 0;
 183
 184         spin_lock(&sdp->sd_quota_spin);
 185
 186         if (qd->qd_slot_count++) {
 187                 spin_unlock(&sdp->sd_quota_spin);
 188                 return 0;
 189         }
 190
 191         for (c = 0; c < sdp->sd_quota_chunks; c++)
 192                 for (o = 0; o < PAGE_SIZE; o++) {
 193                         byte = sdp->sd_quota_bitmap[c][o];
 194                         if (byte != 0xFF)
 195                                 goto found;
 196                 }
 197
 198         goto fail;
 199
 200  found:
 201         for (b = 0; b < 8; b++)
 202                 if (!(byte & (1 << b)))
 203                         break;
 204         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
 205
 206         if (qd->qd_slot >= sdp->sd_quota_slots)
 207                 goto fail;
 208
 209         sdp->sd_quota_bitmap[c][o] |= 1 << b;
 210
 211         spin_unlock(&sdp->sd_quota_spin);
 212
 213         return 0;
 214
 215  fail:
 216         qd->qd_slot_count--;
 217         spin_unlock(&sdp->sd_quota_spin);
 218         return -ENOSPC;
 219 }
 220
 221 static void slot_hold(struct gfs2_quota_data *qd)
 222 {
 223         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 224
 225         spin_lock(&sdp->sd_quota_spin);
 226         gfs2_assert(sdp, qd->qd_slot_count);
 227         qd->qd_slot_count++;
 228         spin_unlock(&sdp->sd_quota_spin);
 229 }
 230
 231 static void slot_put(struct gfs2_quota_data *qd)
 232 {
 233         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 234
 235         spin_lock(&sdp->sd_quota_spin);
 236         gfs2_assert(sdp, qd->qd_slot_count);
 237         if (!--qd->qd_slot_count) {
 238                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
 239                 qd->qd_slot = -1;
 240         }
 241         spin_unlock(&sdp->sd_quota_spin);
 242 }
 243
 244 static int bh_get(struct gfs2_quota_data *qd)
 245 {
 246         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 247         struct gfs2_inode *ip = get_v2ip(sdp->sd_qc_inode);
 248         unsigned int block, offset;
 249         uint64_t dblock;
 250         int new = 0;
 251         struct buffer_head *bh;
 252         int error;
 253
 254         down(&sdp->sd_quota_mutex);
 255
 256         if (qd->qd_bh_count++) {
 257                 up(&sdp->sd_quota_mutex);
 258                 return 0;
 259         }
 260
 261         block = qd->qd_slot / sdp->sd_qc_per_block;
 262         offset = qd->qd_slot % sdp->sd_qc_per_block;;
 263
 264         error = gfs2_block_map(ip, block, &new, &dblock, NULL);
 265         if (error)
 266                 goto fail;
 267         error = gfs2_meta_read(ip->i_gl, dblock, DIO_START | DIO_WAIT, &bh);
 268         if (error)
 269                 goto fail;
 270         error = -EIO;
 271         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
 272                 goto fail_brelse;
 273
 274         qd->qd_bh = bh;
 275         qd->qd_bh_qc = (struct gfs2_quota_change *)
 276                 (bh->b_data + sizeof(struct gfs2_meta_header) +
 277                  offset * sizeof(struct gfs2_quota_change));
 278
 279         up(&sdp->sd_quota_mutex);
 280
 281         return 0;
 282
 283  fail_brelse:
 284         brelse(bh);
 285
 286  fail:
 287         qd->qd_bh_count--;
 288         up(&sdp->sd_quota_mutex);
 289         return error;
 290 }
 291
 292 static void bh_put(struct gfs2_quota_data *qd)
 293 {
 294         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 295
 296         down(&sdp->sd_quota_mutex);
 297         gfs2_assert(sdp, qd->qd_bh_count);
 298         if (!--qd->qd_bh_count) {
 299                 brelse(qd->qd_bh);
 300                 qd->qd_bh = NULL;
 301                 qd->qd_bh_qc = NULL;
 302         }
 303         up(&sdp->sd_quota_mutex);
 304 }
 305
 306 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
 307 {
 308         struct gfs2_quota_data *qd = NULL;
 309         int error;
 310         int found = 0;
 311
 312         *qdp = NULL;
 313
 314         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 315                 return 0;
 316
 317         spin_lock(&sdp->sd_quota_spin);
 318
 319         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 320                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 321                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
 322                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
 323                         continue;
 324
 325                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 326
 327                 set_bit(QDF_LOCKED, &qd->qd_flags);
 328                 gfs2_assert_warn(sdp, qd->qd_count);
 329                 qd->qd_count++;
 330                 qd->qd_change_sync = qd->qd_change;
 331                 gfs2_assert_warn(sdp, qd->qd_slot_count);
 332                 qd->qd_slot_count++;
 333                 found = 1;
 334
 335                 break;
 336         }
 337
 338         if (!found)
 339                 qd = NULL;
 340
 341         spin_unlock(&sdp->sd_quota_spin);
 342
 343         if (qd) {
 344                 gfs2_assert_warn(sdp, qd->qd_change_sync);
 345                 error = bh_get(qd);
 346                 if (error) {
 347                         clear_bit(QDF_LOCKED, &qd->qd_flags);
 348                         slot_put(qd);
 349                         qd_put(qd);
 350                         return error;
 351                 }
 352         }
 353
 354         *qdp = qd;
 355
 356         return 0;
 357 }
 358
 359 static int qd_trylock(struct gfs2_quota_data *qd)
 360 {
 361         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 362
 363         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 364                 return 0;
 365
 366         spin_lock(&sdp->sd_quota_spin);
 367
 368         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 369             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
 370                 spin_unlock(&sdp->sd_quota_spin);
 371                 return 0;
 372         }
 373
 374         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 375
 376         set_bit(QDF_LOCKED, &qd->qd_flags);
 377         gfs2_assert_warn(sdp, qd->qd_count);
 378         qd->qd_count++;
 379         qd->qd_change_sync = qd->qd_change;
 380         gfs2_assert_warn(sdp, qd->qd_slot_count);
 381         qd->qd_slot_count++;
 382
 383         spin_unlock(&sdp->sd_quota_spin);
 384
 385         gfs2_assert_warn(sdp, qd->qd_change_sync);
 386         if (bh_get(qd)) {
 387                 clear_bit(QDF_LOCKED, &qd->qd_flags);
 388                 slot_put(qd);
 389                 qd_put(qd);
 390                 return 0;
 391         }
 392
 393         return 1;
 394 }
 395
 396 static void qd_unlock(struct gfs2_quota_data *qd)
 397 {
 398         gfs2_assert_warn(qd->qd_gl->gl_sbd, test_bit(QDF_LOCKED, &qd->qd_flags));
 399         clear_bit(QDF_LOCKED, &qd->qd_flags);
 400         bh_put(qd);
 401         slot_put(qd);
 402         qd_put(qd);
 403 }
 404
 405 static int qdsb_get(struct gfs2_sbd *sdp, int user, uint32_t id, int create,
 406                     struct gfs2_quota_data **qdp)
 407 {
 408         int error;
 409
 410         error = qd_get(sdp, user, id, create, qdp);
 411         if (error)
 412                 return error;
 413
 414         error = slot_get(*qdp);
 415         if (error)
 416                 goto fail;
 417
 418         error = bh_get(*qdp);
 419         if (error)
 420                 goto fail_slot;
 421
 422         return 0;
 423
 424  fail_slot:
 425         slot_put(*qdp);
 426
 427  fail:
 428         qd_put(*qdp);
 429         return error;
 430 }
 431
 432 static void qdsb_put(struct gfs2_quota_data *qd)
 433 {
 434         bh_put(qd);
 435         slot_put(qd);
 436         qd_put(qd);
 437 }
 438
 439 int gfs2_quota_hold(struct gfs2_inode *ip, uint32_t uid, uint32_t gid)
 440 {
 441         struct gfs2_sbd *sdp = ip->i_sbd;
 442         struct gfs2_alloc *al = &ip->i_alloc;
 443         struct gfs2_quota_data **qd = al->al_qd;
 444         int error;
 445
 446         if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
 447             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
 448                 return -EIO;
 449
 450         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 451                 return 0;
 452
 453         error = qdsb_get(sdp, QUOTA_USER, ip->i_di.di_uid, CREATE, qd);
 454         if (error)
 455                 goto out;
 456         al->al_qd_num++;
 457         qd++;
 458
 459         error = qdsb_get(sdp, QUOTA_GROUP, ip->i_di.di_gid, CREATE, qd);
 460         if (error)
 461                 goto out;
 462         al->al_qd_num++;
 463         qd++;
 464
 465         if (uid != NO_QUOTA_CHANGE && uid != ip->i_di.di_uid) {
 466                 error = qdsb_get(sdp, QUOTA_USER, uid, CREATE, qd);
 467                 if (error)
 468                         goto out;
 469                 al->al_qd_num++;
 470                 qd++;
 471         }
 472
 473         if (gid != NO_QUOTA_CHANGE && gid != ip->i_di.di_gid) {
 474                 error = qdsb_get(sdp, QUOTA_GROUP, gid, CREATE, qd);
 475                 if (error)
 476                         goto out;
 477                 al->al_qd_num++;
 478                 qd++;
 479         }
 480
 481  out:
 482         if (error)
 483                 gfs2_quota_unhold(ip);
 484
 485         return error;
 486 }
 487
 488 void gfs2_quota_unhold(struct gfs2_inode *ip)
 489 {
 490         struct gfs2_sbd *sdp = ip->i_sbd;
 491         struct gfs2_alloc *al = &ip->i_alloc;
 492         unsigned int x;
 493
 494         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 495
 496         for (x = 0; x < al->al_qd_num; x++) {
 497                 qdsb_put(al->al_qd[x]);
 498                 al->al_qd[x] = NULL;
 499         }
 500         al->al_qd_num = 0;
 501 }
 502
 503 static int sort_qd(const void *a, const void *b)
 504 {
 505         struct gfs2_quota_data *qd_a = *(struct gfs2_quota_data **)a;
 506         struct gfs2_quota_data *qd_b = *(struct gfs2_quota_data **)b;
 507         int ret = 0;
 508
 509         if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
 510             !test_bit(QDF_USER, &qd_b->qd_flags)) {
 511                 if (test_bit(QDF_USER, &qd_a->qd_flags))
 512                         ret = -1;
 513                 else
 514                         ret = 1;
 515         } else {
 516                 if (qd_a->qd_id < qd_b->qd_id)
 517                         ret = -1;
 518                 else if (qd_a->qd_id > qd_b->qd_id)
 519                         ret = 1;
 520         }
 521
 522         return ret;
 523 }
 524
 525 static void do_qc(struct gfs2_quota_data *qd, int64_t change)
 526 {
 527         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 528         struct gfs2_inode *ip = get_v2ip(sdp->sd_qc_inode);
 529         struct gfs2_quota_change *qc = qd->qd_bh_qc;
 530         int64_t x;
 531
 532         down(&sdp->sd_quota_mutex);
 533         gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
 534
 535         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
 536                 qc->qc_change = 0;
 537                 qc->qc_flags = 0;
 538                 if (test_bit(QDF_USER, &qd->qd_flags))
 539                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
 540                 qc->qc_id = cpu_to_be32(qd->qd_id);
 541         }
 542
 543         x = qc->qc_change;
 544         x = be64_to_cpu(x) + change;
 545         qc->qc_change = cpu_to_be64(x);
 546
 547         spin_lock(&sdp->sd_quota_spin);
 548         qd->qd_change = x;
 549         spin_unlock(&sdp->sd_quota_spin);
 550
 551         if (!x) {
 552                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
 553                 clear_bit(QDF_CHANGE, &qd->qd_flags);
 554                 qc->qc_flags = 0;
 555                 qc->qc_id = 0;
 556                 slot_put(qd);
 557                 qd_put(qd);
 558         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
 559                 qd_hold(qd);
 560                 slot_hold(qd);
 561         }
 562
 563         up(&sdp->sd_quota_mutex);
 564 }
 565
 566 /**
 567  * gfs2_adjust_quota
 568  *
 569  * This function was mostly borrowed from gfs2_block_truncate_page which was
 570  * in turn mostly borrowed from ext3
 571  */
 572 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 573                              int64_t change, struct gfs2_quota_data *qd)
 574 {
 575         struct inode *inode = ip->i_vnode;
 576         struct address_space *mapping = inode->i_mapping;
 577         unsigned long index = loc >> PAGE_CACHE_SHIFT;
 578         unsigned offset = loc & (PAGE_CACHE_SHIFT - 1);
 579         unsigned blocksize, iblock, pos;
 580         struct buffer_head *bh;
 581         struct page *page;
 582         void *kaddr;
 583         __be64 *ptr;
 584         u64 value;
 585         int err = -EIO;
 586
 587         page = grab_cache_page(mapping, index);
 588         if (!page)
 589                 return -ENOMEM;
 590
 591         blocksize = inode->i_sb->s_blocksize;
 592         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
 593
 594         if (!page_has_buffers(page))
 595                 create_empty_buffers(page, blocksize, 0);
 596
 597         bh = page_buffers(page);
 598         pos = blocksize;
 599         while (offset >= pos) {
 600                 bh = bh->b_this_page;
 601                 iblock++;
 602                 pos += blocksize;
 603         }
 604
 605         if (!buffer_mapped(bh)) {
 606                 gfs2_get_block(inode, iblock, bh, 1);
 607                 if (!buffer_mapped(bh))
 608                         goto unlock;
 609         }
 610
 611         if (PageUptodate(page))
 612                 set_buffer_uptodate(bh);
 613
 614         if (!buffer_uptodate(bh)) {
 615                 ll_rw_block(READ, 1, &bh);
 616                 wait_on_buffer(bh);
 617                 if (!buffer_uptodate(bh))
 618                         goto unlock;
 619         }
 620
 621         gfs2_trans_add_bh(ip->i_gl, bh, 0);
 622
 623         kaddr = kmap_atomic(page, KM_USER0);
 624         ptr = (__be64 *)(kaddr + offset);
 625         value = *ptr = cpu_to_be64(be64_to_cpu(*ptr) + change);
 626         flush_dcache_page(page);
 627         kunmap_atomic(kaddr, KM_USER0);
 628         err = 0;
 629         qd->qd_qb.qb_magic = cpu_to_be32(GFS2_MAGIC);
 630 #if 0
 631         qd->qd_qb.qb_limit = cpu_to_be64(q.qu_limit);
 632         qd->qd_qb.qb_warn = cpu_to_be64(q.qu_warn);
 633 #endif
 634         qd->qd_qb.qb_value = cpu_to_be64(value);
 635 unlock:
 636         unlock_page(page);
 637         page_cache_release(page);
 638         return err;
 639 }
 640
 641 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 642 {
 643         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
 644         struct gfs2_inode *ip = get_v2ip(sdp->sd_quota_inode);
 645         unsigned int data_blocks, ind_blocks;
 646         struct file_ra_state ra_state;
 647         struct gfs2_holder *ghs, i_gh;
 648         unsigned int qx, x;
 649         struct gfs2_quota_data *qd;
 650         loff_t offset;
 651         unsigned int nalloc = 0;
 652         struct gfs2_alloc *al = NULL;
 653         int error;
 654
 655         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 656                               &data_blocks, &ind_blocks);
 657
 658         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_KERNEL);
 659         if (!ghs)
 660                 return -ENOMEM;
 661
 662         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 663         for (qx = 0; qx < num_qd; qx++) {
 664                 error = gfs2_glock_nq_init(qda[qx]->qd_gl,
 665                                            LM_ST_EXCLUSIVE,
 666                                            GL_NOCACHE, &ghs[qx]);
 667                 if (error)
 668                         goto out;
 669         }
 670
 671         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 672         if (error)
 673                 goto out;
 674
 675         for (x = 0; x < num_qd; x++) {
 676                 int alloc_required;
 677
 678                 offset = qd2offset(qda[x]);
 679                 error = gfs2_write_alloc_required(ip, offset,
 680                                                   sizeof(struct gfs2_quota),
 681                                                   &alloc_required);
 682                 if (error)
 683                         goto out_gunlock;
 684                 if (alloc_required)
 685                         nalloc++;
 686         }
 687
 688         if (nalloc) {
 689                 al = gfs2_alloc_get(ip);
 690
 691                 al->al_requested = nalloc * (data_blocks + ind_blocks);
 692
 693                 error = gfs2_inplace_reserve(ip);
 694                 if (error)
 695                         goto out_alloc;
 696
 697                 error = gfs2_trans_begin(sdp,
 698                                          al->al_rgd->rd_ri.ri_length +
 699                                          num_qd * data_blocks +
 700                                          nalloc * ind_blocks +
 701                                          RES_DINODE + num_qd +
 702                                          RES_STATFS, 0);
 703                 if (error)
 704                         goto out_ipres;
 705         } else {
 706                 error = gfs2_trans_begin(sdp,
 707                                          num_qd * data_blocks +
 708                                          RES_DINODE + num_qd, 0);
 709                 if (error)
 710                         goto out_gunlock;
 711         }
 712
 713         file_ra_state_init(&ra_state, ip->i_vnode->i_mapping);
 714         for (x = 0; x < num_qd; x++) {
 715                 qd = qda[x];
 716                 offset = qd2offset(qd);
 717                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync,
 718                                           (struct gfs2_quota_data *)qd->qd_gl->gl_lvb);
 719                 if (error)
 720                         goto out_end_trans;
 721
 722                 do_qc(qd, -qd->qd_change_sync);
 723         }
 724
 725         error = 0;
 726
 727  out_end_trans:
 728         gfs2_trans_end(sdp);
 729
 730  out_ipres:
 731         if (nalloc)
 732                 gfs2_inplace_release(ip);
 733
 734  out_alloc:
 735         if (nalloc)
 736                 gfs2_alloc_put(ip);
 737
 738  out_gunlock:
 739         gfs2_glock_dq_uninit(&i_gh);
 740
 741  out:
 742         while (qx--)
 743                 gfs2_glock_dq_uninit(&ghs[qx]);
 744         kfree(ghs);
 745         gfs2_log_flush_glock(ip->i_gl);
 746
 747         return error;
 748 }
 749
 750 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 751                     struct gfs2_holder *q_gh)
 752 {
 753         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 754         struct gfs2_holder i_gh;
 755         struct gfs2_quota q;
 756         char buf[sizeof(struct gfs2_quota)];
 757         struct file_ra_state ra_state;
 758         int error;
 759
 760         file_ra_state_init(&ra_state, sdp->sd_quota_inode->i_mapping);
 761  restart:
 762         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 763         if (error)
 764                 return error;
 765
 766         gfs2_quota_lvb_in(&qd->qd_qb, qd->qd_gl->gl_lvb);
 767
 768         if (force_refresh || qd->qd_qb.qb_magic != GFS2_MAGIC) {
 769                 loff_t pos;
 770                 gfs2_glock_dq_uninit(q_gh);
 771                 error = gfs2_glock_nq_init(qd->qd_gl,
 772                                           LM_ST_EXCLUSIVE, GL_NOCACHE,
 773                                           q_gh);
 774                 if (error)
 775                         return error;
 776
 777                 error = gfs2_glock_nq_init(get_v2ip(sdp->sd_quota_inode)->i_gl,
 778                                           LM_ST_SHARED, 0,
 779                                           &i_gh);
 780                 if (error)
 781                         goto fail;
 782
 783                 memset(buf, 0, sizeof(struct gfs2_quota));
 784                 pos = qd2offset(qd);
 785                 error = gfs2_internal_read(get_v2ip(sdp->sd_quota_inode),
 786                                             &ra_state, buf,
 787                                             &pos,
 788                                             sizeof(struct gfs2_quota));
 789                 if (error < 0)
 790                         goto fail_gunlock;
 791
 792                 gfs2_glock_dq_uninit(&i_gh);
 793
 794                 gfs2_quota_in(&q, buf);
 795
 796                 memset(&qd->qd_qb, 0, sizeof(struct gfs2_quota_lvb));
 797                 qd->qd_qb.qb_magic = GFS2_MAGIC;
 798                 qd->qd_qb.qb_limit = q.qu_limit;
 799                 qd->qd_qb.qb_warn = q.qu_warn;
 800                 qd->qd_qb.qb_value = q.qu_value;
 801
 802                 gfs2_quota_lvb_out(&qd->qd_qb, qd->qd_gl->gl_lvb);
 803
 804                 if (gfs2_glock_is_blocking(qd->qd_gl)) {
 805                         gfs2_glock_dq_uninit(q_gh);
 806                         force_refresh = 0;
 807                         goto restart;
 808                 }
 809         }
 810
 811         return 0;
 812
 813  fail_gunlock:
 814         gfs2_glock_dq_uninit(&i_gh);
 815
 816  fail:
 817         gfs2_glock_dq_uninit(q_gh);
 818
 819         return error;
 820 }
 821
 822 int gfs2_quota_lock(struct gfs2_inode *ip, uint32_t uid, uint32_t gid)
 823 {
 824         struct gfs2_sbd *sdp = ip->i_sbd;
 825         struct gfs2_alloc *al = &ip->i_alloc;
 826         unsigned int x;
 827         int error = 0;
 828
 829         gfs2_quota_hold(ip, uid, gid);
 830
 831         if (capable(CAP_SYS_RESOURCE) ||
 832             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 833                 return 0;
 834
 835         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
 836              sort_qd, NULL);
 837
 838         for (x = 0; x < al->al_qd_num; x++) {
 839                 error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
 840                 if (error)
 841                         break;
 842         }
 843
 844         if (!error)
 845                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
 846         else {
 847                 while (x--)
 848                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 849                 gfs2_quota_unhold(ip);
 850         }
 851
 852         return error;
 853 }
 854
 855 static int need_sync(struct gfs2_quota_data *qd)
 856 {
 857         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 858         struct gfs2_tune *gt = &sdp->sd_tune;
 859         int64_t value;
 860         unsigned int num, den;
 861         int do_sync = 1;
 862
 863         if (!qd->qd_qb.qb_limit)
 864                 return 0;
 865
 866         spin_lock(&sdp->sd_quota_spin);
 867         value = qd->qd_change;
 868         spin_unlock(&sdp->sd_quota_spin);
 869
 870         spin_lock(&gt->gt_spin);
 871         num = gt->gt_quota_scale_num;
 872         den = gt->gt_quota_scale_den;
 873         spin_unlock(&gt->gt_spin);
 874
 875         if (value < 0)
 876                 do_sync = 0;
 877         else if (qd->qd_qb.qb_value >= (int64_t)qd->qd_qb.qb_limit)
 878                 do_sync = 0;
 879         else {
 880                 value *= gfs2_jindex_size(sdp) * num;
 881                 do_div(value, den);
 882                 value += qd->qd_qb.qb_value;
 883                 if (value < (int64_t)qd->qd_qb.qb_limit)
 884                         do_sync = 0;
 885         }
 886
 887         return do_sync;
 888 }
 889
 890 void gfs2_quota_unlock(struct gfs2_inode *ip)
 891 {
 892         struct gfs2_alloc *al = &ip->i_alloc;
 893         struct gfs2_quota_data *qda[4];
 894         unsigned int count = 0;
 895         unsigned int x;
 896
 897         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
 898                 goto out;
 899
 900         for (x = 0; x < al->al_qd_num; x++) {
 901                 struct gfs2_quota_data *qd;
 902                 int sync;
 903
 904                 qd = al->al_qd[x];
 905                 sync = need_sync(qd);
 906
 907                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 908
 909                 if (sync && qd_trylock(qd))
 910                         qda[count++] = qd;
 911         }
 912
 913         if (count) {
 914                 do_sync(count, qda);
 915                 for (x = 0; x < count; x++)
 916                         qd_unlock(qda[x]);
 917         }
 918
 919  out:
 920         gfs2_quota_unhold(ip);
 921 }
 922
 923 #define MAX_LINE 256
 924
 925 static int print_message(struct gfs2_quota_data *qd, char *type)
 926 {
 927         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 928         char *line;
 929         int len;
 930
 931         line = kmalloc(MAX_LINE, GFP_KERNEL);
 932         if (!line)
 933                 return -ENOMEM;
 934
 935         len = snprintf(line, MAX_LINE-1, "GFS2: fsid=%s: quota %s for %s %u\r\n",
 936                        sdp->sd_fsname, type,
 937                        (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
 938                        qd->qd_id);
 939         line[MAX_LINE-1] = 0;
 940
 941         if (current->signal) { /* Is this test still required? */
 942                 tty_write_message(current->signal->tty, line);
 943         }
 944
 945         kfree(line);
 946
 947         return 0;
 948 }
 949
 950 int gfs2_quota_check(struct gfs2_inode *ip, uint32_t uid, uint32_t gid)
 951 {
 952         struct gfs2_sbd *sdp = ip->i_sbd;
 953         struct gfs2_alloc *al = &ip->i_alloc;
 954         struct gfs2_quota_data *qd;
 955         int64_t value;
 956         unsigned int x;
 957         int error = 0;
 958
 959         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
 960                 return 0;
 961
 962         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 963                 return 0;
 964
 965         for (x = 0; x < al->al_qd_num; x++) {
 966                 qd = al->al_qd[x];
 967
 968                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
 969                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
 970                         continue;
 971
 972                 value = qd->qd_qb.qb_value;
 973                 spin_lock(&sdp->sd_quota_spin);
 974                 value += qd->qd_change;
 975                 spin_unlock(&sdp->sd_quota_spin);
 976
 977                 if (qd->qd_qb.qb_limit && (int64_t)qd->qd_qb.qb_limit < value) {
 978                         print_message(qd, "exceeded");
 979                         error = -EDQUOT;
 980                         break;
 981                 } else if (qd->qd_qb.qb_warn &&
 982                            (int64_t)qd->qd_qb.qb_warn < value &&
 983                            time_after_eq(jiffies, qd->qd_last_warn +
 984                                          gfs2_tune_get(sdp, gt_quota_warn_period) * HZ)) {
 985                         error = print_message(qd, "warning");
 986                         qd->qd_last_warn = jiffies;
 987                 }
 988         }
 989
 990         return error;
 991 }
 992
 993 void gfs2_quota_change(struct gfs2_inode *ip, int64_t change,
 994                        uint32_t uid, uint32_t gid)
 995 {
 996         struct gfs2_alloc *al = &ip->i_alloc;
 997         struct gfs2_quota_data *qd;
 998         unsigned int x;
 999         unsigned int found = 0;
1000
1001         if (gfs2_assert_warn(ip->i_sbd, change))
1002                 return;
1003         if (ip->i_di.di_flags & GFS2_DIF_SYSTEM)
1004                 return;
1005
1006         for (x = 0; x < al->al_qd_num; x++) {
1007                 qd = al->al_qd[x];
1008
1009                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1010                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
1011                         do_qc(qd, change);
1012                         found++;
1013                 }
1014         }
1015 }
1016
1017 int gfs2_quota_sync(struct gfs2_sbd *sdp)
1018 {
1019         struct gfs2_quota_data **qda;
1020         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1021         unsigned int num_qd;
1022         unsigned int x;
1023         int error = 0;
1024
1025         sdp->sd_quota_sync_gen++;
1026
1027         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1028         if (!qda)
1029                 return -ENOMEM;
1030
1031         do {
1032                 num_qd = 0;
1033
1034                 for (;;) {
1035                         error = qd_fish(sdp, qda + num_qd);
1036                         if (error || !qda[num_qd])
1037                                 break;
1038                         if (++num_qd == max_qd)
1039                                 break;
1040                 }
1041
1042                 if (num_qd) {
1043                         if (!error)
1044                                 error = do_sync(num_qd, qda);
1045                         if (!error)
1046                                 for (x = 0; x < num_qd; x++)
1047                                         qda[x]->qd_sync_gen =
1048                                                 sdp->sd_quota_sync_gen;
1049
1050                         for (x = 0; x < num_qd; x++)
1051                                 qd_unlock(qda[x]);
1052                 }
1053         } while (!error && num_qd == max_qd);
1054
1055         kfree(qda);
1056
1057         return error;
1058 }
1059
1060 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, uint32_t id)
1061 {
1062         struct gfs2_quota_data *qd;
1063         struct gfs2_holder q_gh;
1064         int error;
1065
1066         error = qd_get(sdp, user, id, CREATE, &qd);
1067         if (error)
1068                 return error;
1069
1070         error = do_glock(qd, FORCE, &q_gh);
1071         if (!error)
1072                 gfs2_glock_dq_uninit(&q_gh);
1073
1074         qd_put(qd);
1075
1076         return error;
1077 }
1078
1079 int gfs2_quota_read(struct gfs2_sbd *sdp, int user, uint32_t id,
1080                     struct gfs2_quota *q)
1081 {
1082         struct gfs2_quota_data *qd;
1083         struct gfs2_holder q_gh;
1084         int error;
1085
1086         if (((user) ? (id != current->fsuid) : (!in_group_p(id))) &&
1087             !capable(CAP_SYS_ADMIN))
1088                 return -EACCES;
1089
1090         error = qd_get(sdp, user, id, CREATE, &qd);
1091         if (error)
1092                 return error;
1093
1094         error = do_glock(qd, NO_FORCE, &q_gh);
1095         if (error)
1096                 goto out;
1097
1098         memset(q, 0, sizeof(struct gfs2_quota));
1099         q->qu_limit = qd->qd_qb.qb_limit;
1100         q->qu_warn = qd->qd_qb.qb_warn;
1101         q->qu_value = qd->qd_qb.qb_value;
1102
1103         spin_lock(&sdp->sd_quota_spin);
1104         q->qu_value += qd->qd_change;
1105         spin_unlock(&sdp->sd_quota_spin);
1106
1107         gfs2_glock_dq_uninit(&q_gh);
1108
1109  out:
1110         qd_put(qd);
1111
1112         return error;
1113 }
1114
1115 int gfs2_quota_init(struct gfs2_sbd *sdp)
1116 {
1117         struct gfs2_inode *ip = get_v2ip(sdp->sd_qc_inode);
1118         unsigned int blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
1119         unsigned int x, slot = 0;
1120         unsigned int found = 0;
1121         uint64_t dblock;
1122         uint32_t extlen = 0;
1123         int error;
1124
1125         if (!ip->i_di.di_size ||
1126             ip->i_di.di_size > (64 << 20) ||
1127             ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1)) {
1128                 gfs2_consist_inode(ip);
1129                 return -EIO;
1130         }
1131         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1132         sdp->sd_quota_chunks = DIV_RU(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1133
1134         error = -ENOMEM;
1135
1136         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1137                                        sizeof(unsigned char *), GFP_KERNEL);
1138         if (!sdp->sd_quota_bitmap)
1139                 return error;
1140
1141         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1142                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_KERNEL);
1143                 if (!sdp->sd_quota_bitmap[x])
1144                         goto fail;
1145         }
1146
1147         for (x = 0; x < blocks; x++) {
1148                 struct buffer_head *bh;
1149                 unsigned int y;
1150
1151                 if (!extlen) {
1152                         int new = 0;
1153                         error = gfs2_block_map(ip, x, &new, &dblock, &extlen);
1154                         if (error)
1155                                 goto fail;
1156                 }
1157                 gfs2_meta_ra(ip->i_gl,  dblock, extlen);
1158                 error = gfs2_meta_read(ip->i_gl, dblock, DIO_START | DIO_WAIT,
1159                                        &bh);
1160                 if (error)
1161                         goto fail;
1162                 error = -EIO;
1163                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1164                         brelse(bh);
1165                         goto fail;
1166                 }
1167
1168                 for (y = 0;
1169                      y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1170                      y++, slot++) {
1171                         struct gfs2_quota_change qc;
1172                         struct gfs2_quota_data *qd;
1173
1174                         gfs2_quota_change_in(&qc, bh->b_data +
1175                                           sizeof(struct gfs2_meta_header) +
1176                                           y * sizeof(struct gfs2_quota_change));
1177                         if (!qc.qc_change)
1178                                 continue;
1179
1180                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1181                                          qc.qc_id, &qd);
1182                         if (error) {
1183                                 brelse(bh);
1184                                 goto fail;
1185                         }
1186
1187                         set_bit(QDF_CHANGE, &qd->qd_flags);
1188                         qd->qd_change = qc.qc_change;
1189                         qd->qd_slot = slot;
1190                         qd->qd_slot_count = 1;
1191                         qd->qd_last_touched = jiffies;
1192
1193                         spin_lock(&sdp->sd_quota_spin);
1194                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1195                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1196                         atomic_inc(&sdp->sd_quota_count);
1197                         spin_unlock(&sdp->sd_quota_spin);
1198
1199                         found++;
1200                 }
1201
1202                 brelse(bh);
1203                 dblock++;
1204                 extlen--;
1205         }
1206
1207         if (found)
1208                 fs_info(sdp, "found %u quota changes\n", found);
1209
1210         return 0;
1211
1212  fail:
1213         gfs2_quota_cleanup(sdp);
1214         return error;
1215 }
1216
1217 void gfs2_quota_scan(struct gfs2_sbd *sdp)
1218 {
1219         struct gfs2_quota_data *qd, *safe;
1220         LIST_HEAD(dead);
1221
1222         spin_lock(&sdp->sd_quota_spin);
1223         list_for_each_entry_safe(qd, safe, &sdp->sd_quota_list, qd_list) {
1224                 if (!qd->qd_count &&
1225                     time_after_eq(jiffies, qd->qd_last_touched +
1226                                 gfs2_tune_get(sdp, gt_quota_cache_secs) * HZ)) {
1227                         list_move(&qd->qd_list, &dead);
1228                         gfs2_assert_warn(sdp,
1229                                          atomic_read(&sdp->sd_quota_count) > 0);
1230                         atomic_dec(&sdp->sd_quota_count);
1231                 }
1232         }
1233         spin_unlock(&sdp->sd_quota_spin);
1234
1235         while (!list_empty(&dead)) {
1236                 qd = list_entry(dead.next, struct gfs2_quota_data, qd_list);
1237                 list_del(&qd->qd_list);
1238
1239                 gfs2_assert_warn(sdp, !qd->qd_change);
1240                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1241                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1242
1243                 gfs2_lvb_unhold(qd->qd_gl);
1244                 kfree(qd);
1245         }
1246 }
1247
1248 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1249 {
1250         struct list_head *head = &sdp->sd_quota_list;
1251         struct gfs2_quota_data *qd;
1252         unsigned int x;
1253
1254         spin_lock(&sdp->sd_quota_spin);
1255         while (!list_empty(head)) {
1256                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1257
1258                 if (qd->qd_count > 1 ||
1259                     (qd->qd_count && !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1260                         list_move(&qd->qd_list, head);
1261                         spin_unlock(&sdp->sd_quota_spin);
1262                         schedule();
1263                         spin_lock(&sdp->sd_quota_spin);
1264                         continue;
1265                 }
1266
1267                 list_del(&qd->qd_list);
1268                 atomic_dec(&sdp->sd_quota_count);
1269                 spin_unlock(&sdp->sd_quota_spin);
1270
1271                 if (!qd->qd_count) {
1272                         gfs2_assert_warn(sdp, !qd->qd_change);
1273                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1274                 } else
1275                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1276                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1277
1278                 gfs2_lvb_unhold(qd->qd_gl);
1279                 kfree(qd);
1280
1281                 spin_lock(&sdp->sd_quota_spin);
1282         }
1283         spin_unlock(&sdp->sd_quota_spin);
1284
1285         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1286
1287         if (sdp->sd_quota_bitmap) {
1288                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1289                         kfree(sdp->sd_quota_bitmap[x]);
1290                 kfree(sdp->sd_quota_bitmap);
1291         }
1292 }
1293