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   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2006 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/sort.h>
  45 #include <linux/fs.h>
  46 #include <linux/gfs2_ondisk.h>
  47
  48 #include "gfs2.h"
  49 #include "lm_interface.h"
  50 #include "incore.h"
  51 #include "bmap.h"
  52 #include "glock.h"
  53 #include "glops.h"
  54 #include "log.h"
  55 #include "lvb.h"
  56 #include "meta_io.h"
  57 #include "quota.h"
  58 #include "rgrp.h"
  59 #include "super.h"
  60 #include "trans.h"
  61 #include "inode.h"
  62 #include "ops_file.h"
  63 #include "ops_address.h"
  64 #include "util.h"
  65
  66 #define QUOTA_USER 1
  67 #define QUOTA_GROUP 0
  68
  69 static uint64_t qd2offset(struct gfs2_quota_data *qd)
  70 {
  71         uint64_t offset;
  72
  73         offset = 2 * (uint64_t)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
  74         offset *= sizeof(struct gfs2_quota);
  75
  76         return offset;
  77 }
  78
  79 static int qd_alloc(struct gfs2_sbd *sdp, int user, uint32_t id,
  80                     struct gfs2_quota_data **qdp)
  81 {
  82         struct gfs2_quota_data *qd;
  83         int error;
  84
  85         qd = kzalloc(sizeof(struct gfs2_quota_data), GFP_KERNEL);
  86         if (!qd)
  87                 return -ENOMEM;
  88
  89         qd->qd_count = 1;
  90         qd->qd_id = id;
  91         if (user)
  92                 set_bit(QDF_USER, &qd->qd_flags);
  93         qd->qd_slot = -1;
  94
  95         error = gfs2_glock_get(sdp, 2 * (uint64_t)id + !user,
  96                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
  97         if (error)
  98                 goto fail;
  99
 100         error = gfs2_lvb_hold(qd->qd_gl);
 101         gfs2_glock_put(qd->qd_gl);
 102         if (error)
 103                 goto fail;
 104
 105         *qdp = qd;
 106
 107         return 0;
 108
 109  fail:
 110         kfree(qd);
 111         return error;
 112 }
 113
 114 static int qd_get(struct gfs2_sbd *sdp, int user, uint32_t id, int create,
 115                   struct gfs2_quota_data **qdp)
 116 {
 117         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
 118         int error, found;
 119
 120         *qdp = NULL;
 121
 122         for (;;) {
 123                 found = 0;
 124                 spin_lock(&sdp->sd_quota_spin);
 125                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 126                         if (qd->qd_id == id &&
 127                             !test_bit(QDF_USER, &qd->qd_flags) == !user) {
 128                                 qd->qd_count++;
 129                                 found = 1;
 130                                 break;
 131                         }
 132                 }
 133
 134                 if (!found)
 135                         qd = NULL;
 136
 137                 if (!qd && new_qd) {
 138                         qd = new_qd;
 139                         list_add(&qd->qd_list, &sdp->sd_quota_list);
 140                         atomic_inc(&sdp->sd_quota_count);
 141                         new_qd = NULL;
 142                 }
 143
 144                 spin_unlock(&sdp->sd_quota_spin);
 145
 146                 if (qd || !create) {
 147                         if (new_qd) {
 148                                 gfs2_lvb_unhold(new_qd->qd_gl);
 149                                 kfree(new_qd);
 150                         }
 151                         *qdp = qd;
 152                         return 0;
 153                 }
 154
 155                 error = qd_alloc(sdp, user, id, &new_qd);
 156                 if (error)
 157                         return error;
 158         }
 159 }
 160
 161 static void qd_hold(struct gfs2_quota_data *qd)
 162 {
 163         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 164
 165         spin_lock(&sdp->sd_quota_spin);
 166         gfs2_assert(sdp, qd->qd_count);
 167         qd->qd_count++;
 168         spin_unlock(&sdp->sd_quota_spin);
 169 }
 170
 171 static void qd_put(struct gfs2_quota_data *qd)
 172 {
 173         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 174         spin_lock(&sdp->sd_quota_spin);
 175         gfs2_assert(sdp, qd->qd_count);
 176         if (!--qd->qd_count)
 177                 qd->qd_last_touched = jiffies;
 178         spin_unlock(&sdp->sd_quota_spin);
 179 }
 180
 181 static int slot_get(struct gfs2_quota_data *qd)
 182 {
 183         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 184         unsigned int c, o = 0, b;
 185         unsigned char byte = 0;
 186
 187         spin_lock(&sdp->sd_quota_spin);
 188
 189         if (qd->qd_slot_count++) {
 190                 spin_unlock(&sdp->sd_quota_spin);
 191                 return 0;
 192         }
 193
 194         for (c = 0; c < sdp->sd_quota_chunks; c++)
 195                 for (o = 0; o < PAGE_SIZE; o++) {
 196                         byte = sdp->sd_quota_bitmap[c][o];
 197                         if (byte != 0xFF)
 198                                 goto found;
 199                 }
 200
 201         goto fail;
 202
 203  found:
 204         for (b = 0; b < 8; b++)
 205                 if (!(byte & (1 << b)))
 206                         break;
 207         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
 208
 209         if (qd->qd_slot >= sdp->sd_quota_slots)
 210                 goto fail;
 211
 212         sdp->sd_quota_bitmap[c][o] |= 1 << b;
 213
 214         spin_unlock(&sdp->sd_quota_spin);
 215
 216         return 0;
 217
 218  fail:
 219         qd->qd_slot_count--;
 220         spin_unlock(&sdp->sd_quota_spin);
 221         return -ENOSPC;
 222 }
 223
 224 static void slot_hold(struct gfs2_quota_data *qd)
 225 {
 226         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 227
 228         spin_lock(&sdp->sd_quota_spin);
 229         gfs2_assert(sdp, qd->qd_slot_count);
 230         qd->qd_slot_count++;
 231         spin_unlock(&sdp->sd_quota_spin);
 232 }
 233
 234 static void slot_put(struct gfs2_quota_data *qd)
 235 {
 236         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 237
 238         spin_lock(&sdp->sd_quota_spin);
 239         gfs2_assert(sdp, qd->qd_slot_count);
 240         if (!--qd->qd_slot_count) {
 241                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
 242                 qd->qd_slot = -1;
 243         }
 244         spin_unlock(&sdp->sd_quota_spin);
 245 }
 246
 247 static int bh_get(struct gfs2_quota_data *qd)
 248 {
 249         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 250         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 251         unsigned int block, offset;
 252         uint64_t dblock;
 253         int new = 0;
 254         struct buffer_head *bh;
 255         int error;
 256         int boundary;
 257
 258         mutex_lock(&sdp->sd_quota_mutex);
 259
 260         if (qd->qd_bh_count++) {
 261                 mutex_unlock(&sdp->sd_quota_mutex);
 262                 return 0;
 263         }
 264
 265         block = qd->qd_slot / sdp->sd_qc_per_block;
 266         offset = qd->qd_slot % sdp->sd_qc_per_block;;
 267
 268         error = gfs2_block_map(&ip->i_inode, block, &new, &dblock, &boundary);
 269         if (error)
 270                 goto fail;
 271         error = gfs2_meta_read(ip->i_gl, dblock, DIO_START | DIO_WAIT, &bh);
 272         if (error)
 273                 goto fail;
 274         error = -EIO;
 275         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
 276                 goto fail_brelse;
 277
 278         qd->qd_bh = bh;
 279         qd->qd_bh_qc = (struct gfs2_quota_change *)
 280                 (bh->b_data + sizeof(struct gfs2_meta_header) +
 281                  offset * sizeof(struct gfs2_quota_change));
 282
 283         mutex_lock(&sdp->sd_quota_mutex);
 284
 285         return 0;
 286
 287  fail_brelse:
 288         brelse(bh);
 289
 290  fail:
 291         qd->qd_bh_count--;
 292         mutex_unlock(&sdp->sd_quota_mutex);
 293         return error;
 294 }
 295
 296 static void bh_put(struct gfs2_quota_data *qd)
 297 {
 298         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 299
 300         mutex_lock(&sdp->sd_quota_mutex);
 301         gfs2_assert(sdp, qd->qd_bh_count);
 302         if (!--qd->qd_bh_count) {
 303                 brelse(qd->qd_bh);
 304                 qd->qd_bh = NULL;
 305                 qd->qd_bh_qc = NULL;
 306         }
 307         mutex_unlock(&sdp->sd_quota_mutex);
 308 }
 309
 310 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
 311 {
 312         struct gfs2_quota_data *qd = NULL;
 313         int error;
 314         int found = 0;
 315
 316         *qdp = NULL;
 317
 318         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 319                 return 0;
 320
 321         spin_lock(&sdp->sd_quota_spin);
 322
 323         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 324                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 325                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
 326                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
 327                         continue;
 328
 329                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 330
 331                 set_bit(QDF_LOCKED, &qd->qd_flags);
 332                 gfs2_assert_warn(sdp, qd->qd_count);
 333                 qd->qd_count++;
 334                 qd->qd_change_sync = qd->qd_change;
 335                 gfs2_assert_warn(sdp, qd->qd_slot_count);
 336                 qd->qd_slot_count++;
 337                 found = 1;
 338
 339                 break;
 340         }
 341
 342         if (!found)
 343                 qd = NULL;
 344
 345         spin_unlock(&sdp->sd_quota_spin);
 346
 347         if (qd) {
 348                 gfs2_assert_warn(sdp, qd->qd_change_sync);
 349                 error = bh_get(qd);
 350                 if (error) {
 351                         clear_bit(QDF_LOCKED, &qd->qd_flags);
 352                         slot_put(qd);
 353                         qd_put(qd);
 354                         return error;
 355                 }
 356         }
 357
 358         *qdp = qd;
 359
 360         return 0;
 361 }
 362
 363 static int qd_trylock(struct gfs2_quota_data *qd)
 364 {
 365         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 366
 367         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 368                 return 0;
 369
 370         spin_lock(&sdp->sd_quota_spin);
 371
 372         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 373             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
 374                 spin_unlock(&sdp->sd_quota_spin);
 375                 return 0;
 376         }
 377
 378         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 379
 380         set_bit(QDF_LOCKED, &qd->qd_flags);
 381         gfs2_assert_warn(sdp, qd->qd_count);
 382         qd->qd_count++;
 383         qd->qd_change_sync = qd->qd_change;
 384         gfs2_assert_warn(sdp, qd->qd_slot_count);
 385         qd->qd_slot_count++;
 386
 387         spin_unlock(&sdp->sd_quota_spin);
 388
 389         gfs2_assert_warn(sdp, qd->qd_change_sync);
 390         if (bh_get(qd)) {
 391                 clear_bit(QDF_LOCKED, &qd->qd_flags);
 392                 slot_put(qd);
 393                 qd_put(qd);
 394                 return 0;
 395         }
 396
 397         return 1;
 398 }
 399
 400 static void qd_unlock(struct gfs2_quota_data *qd)
 401 {
 402         gfs2_assert_warn(qd->qd_gl->gl_sbd,
 403                          test_bit(QDF_LOCKED, &qd->qd_flags));
 404         clear_bit(QDF_LOCKED, &qd->qd_flags);
 405         bh_put(qd);
 406         slot_put(qd);
 407         qd_put(qd);
 408 }
 409
 410 static int qdsb_get(struct gfs2_sbd *sdp, int user, uint32_t id, int create,
 411                     struct gfs2_quota_data **qdp)
 412 {
 413         int error;
 414
 415         error = qd_get(sdp, user, id, create, qdp);
 416         if (error)
 417                 return error;
 418
 419         error = slot_get(*qdp);
 420         if (error)
 421                 goto fail;
 422
 423         error = bh_get(*qdp);
 424         if (error)
 425                 goto fail_slot;
 426
 427         return 0;
 428
 429  fail_slot:
 430         slot_put(*qdp);
 431
 432  fail:
 433         qd_put(*qdp);
 434         return error;
 435 }
 436
 437 static void qdsb_put(struct gfs2_quota_data *qd)
 438 {
 439         bh_put(qd);
 440         slot_put(qd);
 441         qd_put(qd);
 442 }
 443
 444 int gfs2_quota_hold(struct gfs2_inode *ip, uint32_t uid, uint32_t gid)
 445 {
 446         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 447         struct gfs2_alloc *al = &ip->i_alloc;
 448         struct gfs2_quota_data **qd = al->al_qd;
 449         int error;
 450
 451         if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
 452             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
 453                 return -EIO;
 454
 455         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 456                 return 0;
 457
 458         error = qdsb_get(sdp, QUOTA_USER, ip->i_di.di_uid, CREATE, qd);
 459         if (error)
 460                 goto out;
 461         al->al_qd_num++;
 462         qd++;
 463
 464         error = qdsb_get(sdp, QUOTA_GROUP, ip->i_di.di_gid, CREATE, qd);
 465         if (error)
 466                 goto out;
 467         al->al_qd_num++;
 468         qd++;
 469
 470         if (uid != NO_QUOTA_CHANGE && uid != ip->i_di.di_uid) {
 471                 error = qdsb_get(sdp, QUOTA_USER, uid, CREATE, qd);
 472                 if (error)
 473                         goto out;
 474                 al->al_qd_num++;
 475                 qd++;
 476         }
 477
 478         if (gid != NO_QUOTA_CHANGE && gid != ip->i_di.di_gid) {
 479                 error = qdsb_get(sdp, QUOTA_GROUP, gid, CREATE, qd);
 480                 if (error)
 481                         goto out;
 482                 al->al_qd_num++;
 483                 qd++;
 484         }
 485
 486  out:
 487         if (error)
 488                 gfs2_quota_unhold(ip);
 489
 490         return error;
 491 }
 492
 493 void gfs2_quota_unhold(struct gfs2_inode *ip)
 494 {
 495         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 496         struct gfs2_alloc *al = &ip->i_alloc;
 497         unsigned int x;
 498
 499         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 500
 501         for (x = 0; x < al->al_qd_num; x++) {
 502                 qdsb_put(al->al_qd[x]);
 503                 al->al_qd[x] = NULL;
 504         }
 505         al->al_qd_num = 0;
 506 }
 507
 508 static int sort_qd(const void *a, const void *b)
 509 {
 510         struct gfs2_quota_data *qd_a = *(struct gfs2_quota_data **)a;
 511         struct gfs2_quota_data *qd_b = *(struct gfs2_quota_data **)b;
 512         int ret = 0;
 513
 514         if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
 515             !test_bit(QDF_USER, &qd_b->qd_flags)) {
 516                 if (test_bit(QDF_USER, &qd_a->qd_flags))
 517                         ret = -1;
 518                 else
 519                         ret = 1;
 520         } else {
 521                 if (qd_a->qd_id < qd_b->qd_id)
 522                         ret = -1;
 523                 else if (qd_a->qd_id > qd_b->qd_id)
 524                         ret = 1;
 525         }
 526
 527         return ret;
 528 }
 529
 530 static void do_qc(struct gfs2_quota_data *qd, int64_t change)
 531 {
 532         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 533         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 534         struct gfs2_quota_change *qc = qd->qd_bh_qc;
 535         int64_t x;
 536
 537         mutex_lock(&sdp->sd_quota_mutex);
 538         gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
 539
 540         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
 541                 qc->qc_change = 0;
 542                 qc->qc_flags = 0;
 543                 if (test_bit(QDF_USER, &qd->qd_flags))
 544                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
 545                 qc->qc_id = cpu_to_be32(qd->qd_id);
 546         }
 547
 548         x = qc->qc_change;
 549         x = be64_to_cpu(x) + change;
 550         qc->qc_change = cpu_to_be64(x);
 551
 552         spin_lock(&sdp->sd_quota_spin);
 553         qd->qd_change = x;
 554         spin_unlock(&sdp->sd_quota_spin);
 555
 556         if (!x) {
 557                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
 558                 clear_bit(QDF_CHANGE, &qd->qd_flags);
 559                 qc->qc_flags = 0;
 560                 qc->qc_id = 0;
 561                 slot_put(qd);
 562                 qd_put(qd);
 563         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
 564                 qd_hold(qd);
 565                 slot_hold(qd);
 566         }
 567
 568         mutex_unlock(&sdp->sd_quota_mutex);
 569 }
 570
 571 /**
 572  * gfs2_adjust_quota
 573  *
 574  * This function was mostly borrowed from gfs2_block_truncate_page which was
 575  * in turn mostly borrowed from ext3
 576  */
 577 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 578                              int64_t change, struct gfs2_quota_data *qd)
 579 {
 580         struct inode *inode = &ip->i_inode;
 581         struct address_space *mapping = inode->i_mapping;
 582         unsigned long index = loc >> PAGE_CACHE_SHIFT;
 583         unsigned offset = loc & (PAGE_CACHE_SHIFT - 1);
 584         unsigned blocksize, iblock, pos;
 585         struct buffer_head *bh;
 586         struct page *page;
 587         void *kaddr;
 588         __be64 *ptr;
 589         u64 value;
 590         int err = -EIO;
 591
 592         page = grab_cache_page(mapping, index);
 593         if (!page)
 594                 return -ENOMEM;
 595
 596         blocksize = inode->i_sb->s_blocksize;
 597         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
 598
 599         if (!page_has_buffers(page))
 600                 create_empty_buffers(page, blocksize, 0);
 601
 602         bh = page_buffers(page);
 603         pos = blocksize;
 604         while (offset >= pos) {
 605                 bh = bh->b_this_page;
 606                 iblock++;
 607                 pos += blocksize;
 608         }
 609
 610         if (!buffer_mapped(bh)) {
 611                 gfs2_get_block(inode, iblock, bh, 1);
 612                 if (!buffer_mapped(bh))
 613                         goto unlock;
 614         }
 615
 616         if (PageUptodate(page))
 617                 set_buffer_uptodate(bh);
 618
 619         if (!buffer_uptodate(bh)) {
 620                 ll_rw_block(READ, 1, &bh);
 621                 wait_on_buffer(bh);
 622                 if (!buffer_uptodate(bh))
 623                         goto unlock;
 624         }
 625
 626         gfs2_trans_add_bh(ip->i_gl, bh, 0);
 627
 628         kaddr = kmap_atomic(page, KM_USER0);
 629         ptr = (__be64 *)(kaddr + offset);
 630         value = *ptr = cpu_to_be64(be64_to_cpu(*ptr) + change);
 631         flush_dcache_page(page);
 632         kunmap_atomic(kaddr, KM_USER0);
 633         err = 0;
 634         qd->qd_qb.qb_magic = cpu_to_be32(GFS2_MAGIC);
 635 #if 0
 636         qd->qd_qb.qb_limit = cpu_to_be64(q.qu_limit);
 637         qd->qd_qb.qb_warn = cpu_to_be64(q.qu_warn);
 638 #endif
 639         qd->qd_qb.qb_value = cpu_to_be64(value);
 640 unlock:
 641         unlock_page(page);
 642         page_cache_release(page);
 643         return err;
 644 }
 645
 646 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 647 {
 648         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
 649         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 650         unsigned int data_blocks, ind_blocks;
 651         struct gfs2_holder *ghs, i_gh;
 652         unsigned int qx, x;
 653         struct gfs2_quota_data *qd;
 654         loff_t offset;
 655         unsigned int nalloc = 0;
 656         struct gfs2_alloc *al = NULL;
 657         int error;
 658
 659         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 660                               &data_blocks, &ind_blocks);
 661
 662         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_KERNEL);
 663         if (!ghs)
 664                 return -ENOMEM;
 665
 666         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 667         for (qx = 0; qx < num_qd; qx++) {
 668                 error = gfs2_glock_nq_init(qda[qx]->qd_gl,
 669                                            LM_ST_EXCLUSIVE,
 670                                            GL_NOCACHE, &ghs[qx]);
 671                 if (error)
 672                         goto out;
 673         }
 674
 675         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 676         if (error)
 677                 goto out;
 678
 679         for (x = 0; x < num_qd; x++) {
 680                 int alloc_required;
 681
 682                 offset = qd2offset(qda[x]);
 683                 error = gfs2_write_alloc_required(ip, offset,
 684                                                   sizeof(struct gfs2_quota),
 685                                                   &alloc_required);
 686                 if (error)
 687                         goto out_gunlock;
 688                 if (alloc_required)
 689                         nalloc++;
 690         }
 691
 692         if (nalloc) {
 693                 al = gfs2_alloc_get(ip);
 694
 695                 al->al_requested = nalloc * (data_blocks + ind_blocks);
 696
 697                 error = gfs2_inplace_reserve(ip);
 698                 if (error)
 699                         goto out_alloc;
 700
 701                 error = gfs2_trans_begin(sdp,
 702                                          al->al_rgd->rd_ri.ri_length +
 703                                          num_qd * data_blocks +
 704                                          nalloc * ind_blocks +
 705                                          RES_DINODE + num_qd +
 706                                          RES_STATFS, 0);
 707                 if (error)
 708                         goto out_ipres;
 709         } else {
 710                 error = gfs2_trans_begin(sdp,
 711                                          num_qd * data_blocks +
 712                                          RES_DINODE + num_qd, 0);
 713                 if (error)
 714                         goto out_gunlock;
 715         }
 716
 717         for (x = 0; x < num_qd; x++) {
 718                 qd = qda[x];
 719                 offset = qd2offset(qd);
 720                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync,
 721                                           (struct gfs2_quota_data *)
 722                                           qd->qd_gl->gl_lvb);
 723                 if (error)
 724                         goto out_end_trans;
 725
 726                 do_qc(qd, -qd->qd_change_sync);
 727         }
 728
 729         error = 0;
 730
 731  out_end_trans:
 732         gfs2_trans_end(sdp);
 733
 734  out_ipres:
 735         if (nalloc)
 736                 gfs2_inplace_release(ip);
 737
 738  out_alloc:
 739         if (nalloc)
 740                 gfs2_alloc_put(ip);
 741
 742  out_gunlock:
 743         gfs2_glock_dq_uninit(&i_gh);
 744
 745  out:
 746         while (qx--)
 747                 gfs2_glock_dq_uninit(&ghs[qx]);
 748         kfree(ghs);
 749         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
 750
 751         return error;
 752 }
 753
 754 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 755                     struct gfs2_holder *q_gh)
 756 {
 757         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 758         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 759         struct gfs2_holder i_gh;
 760         struct gfs2_quota q;
 761         char buf[sizeof(struct gfs2_quota)];
 762         struct file_ra_state ra_state;
 763         int error;
 764
 765         file_ra_state_init(&ra_state, sdp->sd_quota_inode->i_mapping);
 766  restart:
 767         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 768         if (error)
 769                 return error;
 770
 771         gfs2_quota_lvb_in(&qd->qd_qb, qd->qd_gl->gl_lvb);
 772
 773         if (force_refresh || qd->qd_qb.qb_magic != GFS2_MAGIC) {
 774                 loff_t pos;
 775                 gfs2_glock_dq_uninit(q_gh);
 776                 error = gfs2_glock_nq_init(qd->qd_gl,
 777                                           LM_ST_EXCLUSIVE, GL_NOCACHE,
 778                                           q_gh);
 779                 if (error)
 780                         return error;
 781
 782                 error = gfs2_glock_nq_init(ip->i_gl,
 783                                           LM_ST_SHARED, 0,
 784                                           &i_gh);
 785                 if (error)
 786                         goto fail;
 787
 788                 memset(buf, 0, sizeof(struct gfs2_quota));
 789                 pos = qd2offset(qd);
 790                 error = gfs2_internal_read(ip, &ra_state, buf,
 791                                            &pos, sizeof(struct gfs2_quota));
 792                 if (error < 0)
 793                         goto fail_gunlock;
 794
 795                 gfs2_glock_dq_uninit(&i_gh);
 796
 797                 gfs2_quota_in(&q, buf);
 798
 799                 memset(&qd->qd_qb, 0, sizeof(struct gfs2_quota_lvb));
 800                 qd->qd_qb.qb_magic = GFS2_MAGIC;
 801                 qd->qd_qb.qb_limit = q.qu_limit;
 802                 qd->qd_qb.qb_warn = q.qu_warn;
 803                 qd->qd_qb.qb_value = q.qu_value;
 804
 805                 gfs2_quota_lvb_out(&qd->qd_qb, qd->qd_gl->gl_lvb);
 806
 807                 if (gfs2_glock_is_blocking(qd->qd_gl)) {
 808                         gfs2_glock_dq_uninit(q_gh);
 809                         force_refresh = 0;
 810                         goto restart;
 811                 }
 812         }
 813
 814         return 0;
 815
 816  fail_gunlock:
 817         gfs2_glock_dq_uninit(&i_gh);
 818
 819  fail:
 820         gfs2_glock_dq_uninit(q_gh);
 821
 822         return error;
 823 }
 824
 825 int gfs2_quota_lock(struct gfs2_inode *ip, uint32_t uid, uint32_t gid)
 826 {
 827         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 828         struct gfs2_alloc *al = &ip->i_alloc;
 829         unsigned int x;
 830         int error = 0;
 831
 832         gfs2_quota_hold(ip, uid, gid);
 833
 834         if (capable(CAP_SYS_RESOURCE) ||
 835             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 836                 return 0;
 837
 838         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
 839              sort_qd, NULL);
 840
 841         for (x = 0; x < al->al_qd_num; x++) {
 842                 error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
 843                 if (error)
 844                         break;
 845         }
 846
 847         if (!error)
 848                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
 849         else {
 850                 while (x--)
 851                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 852                 gfs2_quota_unhold(ip);
 853         }
 854
 855         return error;
 856 }
 857
 858 static int need_sync(struct gfs2_quota_data *qd)
 859 {
 860         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 861         struct gfs2_tune *gt = &sdp->sd_tune;
 862         int64_t value;
 863         unsigned int num, den;
 864         int do_sync = 1;
 865
 866         if (!qd->qd_qb.qb_limit)
 867                 return 0;
 868
 869         spin_lock(&sdp->sd_quota_spin);
 870         value = qd->qd_change;
 871         spin_unlock(&sdp->sd_quota_spin);
 872
 873         spin_lock(&gt->gt_spin);
 874         num = gt->gt_quota_scale_num;
 875         den = gt->gt_quota_scale_den;
 876         spin_unlock(&gt->gt_spin);
 877
 878         if (value < 0)
 879                 do_sync = 0;
 880         else if (qd->qd_qb.qb_value >= (int64_t)qd->qd_qb.qb_limit)
 881                 do_sync = 0;
 882         else {
 883                 value *= gfs2_jindex_size(sdp) * num;
 884                 do_div(value, den);
 885                 value += qd->qd_qb.qb_value;
 886                 if (value < (int64_t)qd->qd_qb.qb_limit)
 887                         do_sync = 0;
 888         }
 889
 890         return do_sync;
 891 }
 892
 893 void gfs2_quota_unlock(struct gfs2_inode *ip)
 894 {
 895         struct gfs2_alloc *al = &ip->i_alloc;
 896         struct gfs2_quota_data *qda[4];
 897         unsigned int count = 0;
 898         unsigned int x;
 899
 900         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
 901                 goto out;
 902
 903         for (x = 0; x < al->al_qd_num; x++) {
 904                 struct gfs2_quota_data *qd;
 905                 int sync;
 906
 907                 qd = al->al_qd[x];
 908                 sync = need_sync(qd);
 909
 910                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 911
 912                 if (sync && qd_trylock(qd))
 913                         qda[count++] = qd;
 914         }
 915
 916         if (count) {
 917                 do_sync(count, qda);
 918                 for (x = 0; x < count; x++)
 919                         qd_unlock(qda[x]);
 920         }
 921
 922  out:
 923         gfs2_quota_unhold(ip);
 924 }
 925
 926 #define MAX_LINE 256
 927
 928 static int print_message(struct gfs2_quota_data *qd, char *type)
 929 {
 930         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 931
 932         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\r\n",
 933                sdp->sd_fsname, type,
 934                (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
 935                qd->qd_id);
 936
 937         return 0;
 938 }
 939
 940 int gfs2_quota_check(struct gfs2_inode *ip, uint32_t uid, uint32_t gid)
 941 {
 942         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 943         struct gfs2_alloc *al = &ip->i_alloc;
 944         struct gfs2_quota_data *qd;
 945         int64_t value;
 946         unsigned int x;
 947         int error = 0;
 948
 949         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
 950                 return 0;
 951
 952         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 953                 return 0;
 954
 955         for (x = 0; x < al->al_qd_num; x++) {
 956                 qd = al->al_qd[x];
 957
 958                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
 959                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
 960                         continue;
 961
 962                 value = qd->qd_qb.qb_value;
 963                 spin_lock(&sdp->sd_quota_spin);
 964                 value += qd->qd_change;
 965                 spin_unlock(&sdp->sd_quota_spin);
 966
 967                 if (qd->qd_qb.qb_limit && (int64_t)qd->qd_qb.qb_limit < value) {
 968                         print_message(qd, "exceeded");
 969                         error = -EDQUOT;
 970                         break;
 971                 } else if (qd->qd_qb.qb_warn &&
 972                            (int64_t)qd->qd_qb.qb_warn < value &&
 973                            time_after_eq(jiffies, qd->qd_last_warn +
 974                                          gfs2_tune_get(sdp,
 975                                                 gt_quota_warn_period) * HZ)) {
 976                         error = print_message(qd, "warning");
 977                         qd->qd_last_warn = jiffies;
 978                 }
 979         }
 980
 981         return error;
 982 }
 983
 984 void gfs2_quota_change(struct gfs2_inode *ip, int64_t change,
 985                        uint32_t uid, uint32_t gid)
 986 {
 987         struct gfs2_alloc *al = &ip->i_alloc;
 988         struct gfs2_quota_data *qd;
 989         unsigned int x;
 990         unsigned int found = 0;
 991
 992         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
 993                 return;
 994         if (ip->i_di.di_flags & GFS2_DIF_SYSTEM)
 995                 return;
 996
 997         for (x = 0; x < al->al_qd_num; x++) {
 998                 qd = al->al_qd[x];
 999
1000                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1001                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
1002                         do_qc(qd, change);
1003                         found++;
1004                 }
1005         }
1006 }
1007
1008 int gfs2_quota_sync(struct gfs2_sbd *sdp)
1009 {
1010         struct gfs2_quota_data **qda;
1011         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1012         unsigned int num_qd;
1013         unsigned int x;
1014         int error = 0;
1015
1016         sdp->sd_quota_sync_gen++;
1017
1018         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1019         if (!qda)
1020                 return -ENOMEM;
1021
1022         do {
1023                 num_qd = 0;
1024
1025                 for (;;) {
1026                         error = qd_fish(sdp, qda + num_qd);
1027                         if (error || !qda[num_qd])
1028                                 break;
1029                         if (++num_qd == max_qd)
1030                                 break;
1031                 }
1032
1033                 if (num_qd) {
1034                         if (!error)
1035                                 error = do_sync(num_qd, qda);
1036                         if (!error)
1037                                 for (x = 0; x < num_qd; x++)
1038                                         qda[x]->qd_sync_gen =
1039                                                 sdp->sd_quota_sync_gen;
1040
1041                         for (x = 0; x < num_qd; x++)
1042                                 qd_unlock(qda[x]);
1043                 }
1044         } while (!error && num_qd == max_qd);
1045
1046         kfree(qda);
1047
1048         return error;
1049 }
1050
1051 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, uint32_t id)
1052 {
1053         struct gfs2_quota_data *qd;
1054         struct gfs2_holder q_gh;
1055         int error;
1056
1057         error = qd_get(sdp, user, id, CREATE, &qd);
1058         if (error)
1059                 return error;
1060
1061         error = do_glock(qd, FORCE, &q_gh);
1062         if (!error)
1063                 gfs2_glock_dq_uninit(&q_gh);
1064
1065         qd_put(qd);
1066
1067         return error;
1068 }
1069
1070 #if 0
1071 int gfs2_quota_read(struct gfs2_sbd *sdp, int user, uint32_t id,
1072                     struct gfs2_quota *q)
1073 {
1074         struct gfs2_quota_data *qd;
1075         struct gfs2_holder q_gh;
1076         int error;
1077
1078         if (((user) ? (id != current->fsuid) : (!in_group_p(id))) &&
1079             !capable(CAP_SYS_ADMIN))
1080                 return -EACCES;
1081
1082         error = qd_get(sdp, user, id, CREATE, &qd);
1083         if (error)
1084                 return error;
1085
1086         error = do_glock(qd, NO_FORCE, &q_gh);
1087         if (error)
1088                 goto out;
1089
1090         memset(q, 0, sizeof(struct gfs2_quota));
1091         q->qu_limit = qd->qd_qb.qb_limit;
1092         q->qu_warn = qd->qd_qb.qb_warn;
1093         q->qu_value = qd->qd_qb.qb_value;
1094
1095         spin_lock(&sdp->sd_quota_spin);
1096         q->qu_value += qd->qd_change;
1097         spin_unlock(&sdp->sd_quota_spin);
1098
1099         gfs2_glock_dq_uninit(&q_gh);
1100
1101  out:
1102         qd_put(qd);
1103
1104         return error;
1105 }
1106 #endif  /*  0  */
1107
1108 int gfs2_quota_init(struct gfs2_sbd *sdp)
1109 {
1110         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1111         unsigned int blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
1112         unsigned int x, slot = 0;
1113         unsigned int found = 0;
1114         uint64_t dblock;
1115         uint32_t extlen = 0;
1116         int error;
1117
1118         if (!ip->i_di.di_size ||
1119             ip->i_di.di_size > (64 << 20) ||
1120             ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1)) {
1121                 gfs2_consist_inode(ip);
1122                 return -EIO;
1123         }
1124         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1125         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1126
1127         error = -ENOMEM;
1128
1129         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1130                                        sizeof(unsigned char *), GFP_KERNEL);
1131         if (!sdp->sd_quota_bitmap)
1132                 return error;
1133
1134         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1135                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_KERNEL);
1136                 if (!sdp->sd_quota_bitmap[x])
1137                         goto fail;
1138         }
1139
1140         for (x = 0; x < blocks; x++) {
1141                 struct buffer_head *bh;
1142                 unsigned int y;
1143
1144                 if (!extlen) {
1145                         int new = 0;
1146                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1147                         if (error)
1148                                 goto fail;
1149                 }
1150                 gfs2_meta_ra(ip->i_gl,  dblock, extlen);
1151                 error = gfs2_meta_read(ip->i_gl, dblock, DIO_START | DIO_WAIT,
1152                                        &bh);
1153                 if (error)
1154                         goto fail;
1155                 error = -EIO;
1156                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1157                         brelse(bh);
1158                         goto fail;
1159                 }
1160
1161                 for (y = 0;
1162                      y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1163                      y++, slot++) {
1164                         struct gfs2_quota_change qc;
1165                         struct gfs2_quota_data *qd;
1166
1167                         gfs2_quota_change_in(&qc, bh->b_data +
1168                                           sizeof(struct gfs2_meta_header) +
1169                                           y * sizeof(struct gfs2_quota_change));
1170                         if (!qc.qc_change)
1171                                 continue;
1172
1173                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1174                                          qc.qc_id, &qd);
1175                         if (error) {
1176                                 brelse(bh);
1177                                 goto fail;
1178                         }
1179
1180                         set_bit(QDF_CHANGE, &qd->qd_flags);
1181                         qd->qd_change = qc.qc_change;
1182                         qd->qd_slot = slot;
1183                         qd->qd_slot_count = 1;
1184                         qd->qd_last_touched = jiffies;
1185
1186                         spin_lock(&sdp->sd_quota_spin);
1187                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1188                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1189                         atomic_inc(&sdp->sd_quota_count);
1190                         spin_unlock(&sdp->sd_quota_spin);
1191
1192                         found++;
1193                 }
1194
1195                 brelse(bh);
1196                 dblock++;
1197                 extlen--;
1198         }
1199
1200         if (found)
1201                 fs_info(sdp, "found %u quota changes\n", found);
1202
1203         return 0;
1204
1205  fail:
1206         gfs2_quota_cleanup(sdp);
1207         return error;
1208 }
1209
1210 void gfs2_quota_scan(struct gfs2_sbd *sdp)
1211 {
1212         struct gfs2_quota_data *qd, *safe;
1213         LIST_HEAD(dead);
1214
1215         spin_lock(&sdp->sd_quota_spin);
1216         list_for_each_entry_safe(qd, safe, &sdp->sd_quota_list, qd_list) {
1217                 if (!qd->qd_count &&
1218                     time_after_eq(jiffies, qd->qd_last_touched +
1219                                 gfs2_tune_get(sdp, gt_quota_cache_secs) * HZ)) {
1220                         list_move(&qd->qd_list, &dead);
1221                         gfs2_assert_warn(sdp,
1222                                          atomic_read(&sdp->sd_quota_count) > 0);
1223                         atomic_dec(&sdp->sd_quota_count);
1224                 }
1225         }
1226         spin_unlock(&sdp->sd_quota_spin);
1227
1228         while (!list_empty(&dead)) {
1229                 qd = list_entry(dead.next, struct gfs2_quota_data, qd_list);
1230                 list_del(&qd->qd_list);
1231
1232                 gfs2_assert_warn(sdp, !qd->qd_change);
1233                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1234                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1235
1236                 gfs2_lvb_unhold(qd->qd_gl);
1237                 kfree(qd);
1238         }
1239 }
1240
1241 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1242 {
1243         struct list_head *head = &sdp->sd_quota_list;
1244         struct gfs2_quota_data *qd;
1245         unsigned int x;
1246
1247         spin_lock(&sdp->sd_quota_spin);
1248         while (!list_empty(head)) {
1249                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1250
1251                 if (qd->qd_count > 1 ||
1252                     (qd->qd_count && !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1253                         list_move(&qd->qd_list, head);
1254                         spin_unlock(&sdp->sd_quota_spin);
1255                         schedule();
1256                         spin_lock(&sdp->sd_quota_spin);
1257                         continue;
1258                 }
1259
1260                 list_del(&qd->qd_list);
1261                 atomic_dec(&sdp->sd_quota_count);
1262                 spin_unlock(&sdp->sd_quota_spin);
1263
1264                 if (!qd->qd_count) {
1265                         gfs2_assert_warn(sdp, !qd->qd_change);
1266                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1267                 } else
1268                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1269                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1270
1271                 gfs2_lvb_unhold(qd->qd_gl);
1272                 kfree(qd);
1273
1274                 spin_lock(&sdp->sd_quota_spin);
1275         }
1276         spin_unlock(&sdp->sd_quota_spin);
1277
1278         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1279
1280         if (sdp->sd_quota_bitmap) {
1281                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1282                         kfree(sdp->sd_quota_bitmap[x]);
1283                 kfree(sdp->sd_quota_bitmap);
1284         }
1285 }
1286