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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 version 2.
   8  */
   9
  10 /*
  11  * Quota change tags are associated with each transaction that allocates or
  12  * deallocates space.  Those changes are accumulated locally to each node (in a
  13  * per-node file) and then are periodically synced to the quota file.  This
  14  * avoids the bottleneck of constantly touching the quota file, but introduces
  15  * fuzziness in the current usage value of IDs that are being used on different
  16  * nodes in the cluster simultaneously.  So, it is possible for a user on
  17  * multiple nodes to overrun their quota, but that overrun is controlable.
  18  * Since quota tags are part of transactions, there is no need to a quota check
  19  * program to be run on node crashes or anything like that.
  20  *
  21  * There are couple of knobs that let the administrator manage the quota
  22  * fuzziness.  "quota_quantum" sets the maximum time a quota change can be
  23  * sitting on one node before being synced to the quota file.  (The default is
  24  * 60 seconds.)  Another knob, "quota_scale" controls how quickly the frequency
  25  * of quota file syncs increases as the user moves closer to their limit.  The
  26  * more frequent the syncs, the more accurate the quota enforcement, but that
  27  * means that there is more contention between the nodes for the quota file.
  28  * The default value is one.  This sets the maximum theoretical quota overrun
  29  * (with infinite node with infinite bandwidth) to twice the user's limit.  (In
  30  * practice, the maximum overrun you see should be much less.)  A "quota_scale"
  31  * number greater than one makes quota syncs more frequent and reduces the
  32  * maximum overrun.  Numbers less than one (but greater than zero) make quota
  33  * syncs less frequent.
  34  *
  35  * GFS quotas also use per-ID Lock Value Blocks (LVBs) to cache the contents of
  36  * the quota file, so it is not being constantly read.
  37  */
  38
  39 #include <linux/sched.h>
  40 #include <linux/slab.h>
  41 #include <linux/spinlock.h>
  42 #include <linux/completion.h>
  43 #include <linux/buffer_head.h>
  44 #include <linux/sort.h>
  45 #include <linux/fs.h>
  46 #include <linux/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 "meta_io.h"
  56 #include "quota.h"
  57 #include "rgrp.h"
  58 #include "super.h"
  59 #include "trans.h"
  60 #include "inode.h"
  61 #include "ops_file.h"
  62 #include "ops_address.h"
  63 #include "util.h"
  64
  65 #define QUOTA_USER 1
  66 #define QUOTA_GROUP 0
  67
  68 static u64 qd2offset(struct gfs2_quota_data *qd)
  69 {
  70         u64 offset;
  71
  72         offset = 2 * (u64)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
  73         offset *= sizeof(struct gfs2_quota);
  74
  75         return offset;
  76 }
  77
  78 static int qd_alloc(struct gfs2_sbd *sdp, int user, u32 id,
  79                     struct gfs2_quota_data **qdp)
  80 {
  81         struct gfs2_quota_data *qd;
  82         int error;
  83
  84         qd = kzalloc(sizeof(struct gfs2_quota_data), GFP_KERNEL);
  85         if (!qd)
  86                 return -ENOMEM;
  87
  88         qd->qd_count = 1;
  89         qd->qd_id = id;
  90         if (user)
  91                 set_bit(QDF_USER, &qd->qd_flags);
  92         qd->qd_slot = -1;
  93
  94         error = gfs2_glock_get(sdp, 2 * (u64)id + !user,
  95                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
  96         if (error)
  97                 goto fail;
  98
  99         error = gfs2_lvb_hold(qd->qd_gl);
 100         gfs2_glock_put(qd->qd_gl);
 101         if (error)
 102                 goto fail;
 103
 104         *qdp = qd;
 105
 106         return 0;
 107
 108 fail:
 109         kfree(qd);
 110         return error;
 111 }
 112
 113 static int qd_get(struct gfs2_sbd *sdp, int user, u32 id, int create,
 114                   struct gfs2_quota_data **qdp)
 115 {
 116         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
 117         int error, found;
 118
 119         *qdp = NULL;
 120
 121         for (;;) {
 122                 found = 0;
 123                 spin_lock(&sdp->sd_quota_spin);
 124                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 125                         if (qd->qd_id == id &&
 126                             !test_bit(QDF_USER, &qd->qd_flags) == !user) {
 127                                 qd->qd_count++;
 128                                 found = 1;
 129                                 break;
 130                         }
 131                 }
 132
 133                 if (!found)
 134                         qd = NULL;
 135
 136                 if (!qd && new_qd) {
 137                         qd = new_qd;
 138                         list_add(&qd->qd_list, &sdp->sd_quota_list);
 139                         atomic_inc(&sdp->sd_quota_count);
 140                         new_qd = NULL;
 141                 }
 142
 143                 spin_unlock(&sdp->sd_quota_spin);
 144
 145                 if (qd || !create) {
 146                         if (new_qd) {
 147                                 gfs2_lvb_unhold(new_qd->qd_gl);
 148                                 kfree(new_qd);
 149                         }
 150                         *qdp = qd;
 151                         return 0;
 152                 }
 153
 154                 error = qd_alloc(sdp, user, id, &new_qd);
 155                 if (error)
 156                         return error;
 157         }
 158 }
 159
 160 static void qd_hold(struct gfs2_quota_data *qd)
 161 {
 162         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 163
 164         spin_lock(&sdp->sd_quota_spin);
 165         gfs2_assert(sdp, qd->qd_count);
 166         qd->qd_count++;
 167         spin_unlock(&sdp->sd_quota_spin);
 168 }
 169
 170 static void qd_put(struct gfs2_quota_data *qd)
 171 {
 172         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 173         spin_lock(&sdp->sd_quota_spin);
 174         gfs2_assert(sdp, qd->qd_count);
 175         if (!--qd->qd_count)
 176                 qd->qd_last_touched = jiffies;
 177         spin_unlock(&sdp->sd_quota_spin);
 178 }
 179
 180 static int slot_get(struct gfs2_quota_data *qd)
 181 {
 182         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 183         unsigned int c, o = 0, b;
 184         unsigned char byte = 0;
 185
 186         spin_lock(&sdp->sd_quota_spin);
 187
 188         if (qd->qd_slot_count++) {
 189                 spin_unlock(&sdp->sd_quota_spin);
 190                 return 0;
 191         }
 192
 193         for (c = 0; c < sdp->sd_quota_chunks; c++)
 194                 for (o = 0; o < PAGE_SIZE; o++) {
 195                         byte = sdp->sd_quota_bitmap[c][o];
 196                         if (byte != 0xFF)
 197                                 goto found;
 198                 }
 199
 200         goto fail;
 201
 202 found:
 203         for (b = 0; b < 8; b++)
 204                 if (!(byte & (1 << b)))
 205                         break;
 206         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
 207
 208         if (qd->qd_slot >= sdp->sd_quota_slots)
 209                 goto fail;
 210
 211         sdp->sd_quota_bitmap[c][o] |= 1 << b;
 212
 213         spin_unlock(&sdp->sd_quota_spin);
 214
 215         return 0;
 216
 217 fail:
 218         qd->qd_slot_count--;
 219         spin_unlock(&sdp->sd_quota_spin);
 220         return -ENOSPC;
 221 }
 222
 223 static void slot_hold(struct gfs2_quota_data *qd)
 224 {
 225         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 226
 227         spin_lock(&sdp->sd_quota_spin);
 228         gfs2_assert(sdp, qd->qd_slot_count);
 229         qd->qd_slot_count++;
 230         spin_unlock(&sdp->sd_quota_spin);
 231 }
 232
 233 static void slot_put(struct gfs2_quota_data *qd)
 234 {
 235         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 236
 237         spin_lock(&sdp->sd_quota_spin);
 238         gfs2_assert(sdp, qd->qd_slot_count);
 239         if (!--qd->qd_slot_count) {
 240                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
 241                 qd->qd_slot = -1;
 242         }
 243         spin_unlock(&sdp->sd_quota_spin);
 244 }
 245
 246 static int bh_get(struct gfs2_quota_data *qd)
 247 {
 248         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 249         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 250         unsigned int block, offset;
 251         u64 dblock;
 252         int new = 0;
 253         struct buffer_head *bh;
 254         int error;
 255         int boundary;
 256
 257         mutex_lock(&sdp->sd_quota_mutex);
 258
 259         if (qd->qd_bh_count++) {
 260                 mutex_unlock(&sdp->sd_quota_mutex);
 261                 return 0;
 262         }
 263
 264         block = qd->qd_slot / sdp->sd_qc_per_block;
 265         offset = qd->qd_slot % sdp->sd_qc_per_block;;
 266
 267         error = gfs2_block_map(&ip->i_inode, block, &new, &dblock, &boundary);
 268         if (error)
 269                 goto fail;
 270         error = gfs2_meta_read(ip->i_gl, dblock, DIO_START | DIO_WAIT, &bh);
 271         if (error)
 272                 goto fail;
 273         error = -EIO;
 274         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
 275                 goto fail_brelse;
 276
 277         qd->qd_bh = bh;
 278         qd->qd_bh_qc = (struct gfs2_quota_change *)
 279                 (bh->b_data + sizeof(struct gfs2_meta_header) +
 280                  offset * sizeof(struct gfs2_quota_change));
 281
 282         mutex_lock(&sdp->sd_quota_mutex);
 283
 284         return 0;
 285
 286 fail_brelse:
 287         brelse(bh);
 288 fail:
 289         qd->qd_bh_count--;
 290         mutex_unlock(&sdp->sd_quota_mutex);
 291         return error;
 292 }
 293
 294 static void bh_put(struct gfs2_quota_data *qd)
 295 {
 296         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 297
 298         mutex_lock(&sdp->sd_quota_mutex);
 299         gfs2_assert(sdp, qd->qd_bh_count);
 300         if (!--qd->qd_bh_count) {
 301                 brelse(qd->qd_bh);
 302                 qd->qd_bh = NULL;
 303                 qd->qd_bh_qc = NULL;
 304         }
 305         mutex_unlock(&sdp->sd_quota_mutex);
 306 }
 307
 308 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
 309 {
 310         struct gfs2_quota_data *qd = NULL;
 311         int error;
 312         int found = 0;
 313
 314         *qdp = NULL;
 315
 316         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 317                 return 0;
 318
 319         spin_lock(&sdp->sd_quota_spin);
 320
 321         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 322                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 323                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
 324                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
 325                         continue;
 326
 327                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 328
 329                 set_bit(QDF_LOCKED, &qd->qd_flags);
 330                 gfs2_assert_warn(sdp, qd->qd_count);
 331                 qd->qd_count++;
 332                 qd->qd_change_sync = qd->qd_change;
 333                 gfs2_assert_warn(sdp, qd->qd_slot_count);
 334                 qd->qd_slot_count++;
 335                 found = 1;
 336
 337                 break;
 338         }
 339
 340         if (!found)
 341                 qd = NULL;
 342
 343         spin_unlock(&sdp->sd_quota_spin);
 344
 345         if (qd) {
 346                 gfs2_assert_warn(sdp, qd->qd_change_sync);
 347                 error = bh_get(qd);
 348                 if (error) {
 349                         clear_bit(QDF_LOCKED, &qd->qd_flags);
 350                         slot_put(qd);
 351                         qd_put(qd);
 352                         return error;
 353                 }
 354         }
 355
 356         *qdp = qd;
 357
 358         return 0;
 359 }
 360
 361 static int qd_trylock(struct gfs2_quota_data *qd)
 362 {
 363         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 364
 365         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 366                 return 0;
 367
 368         spin_lock(&sdp->sd_quota_spin);
 369
 370         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 371             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
 372                 spin_unlock(&sdp->sd_quota_spin);
 373                 return 0;
 374         }
 375
 376         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 377
 378         set_bit(QDF_LOCKED, &qd->qd_flags);
 379         gfs2_assert_warn(sdp, qd->qd_count);
 380         qd->qd_count++;
 381         qd->qd_change_sync = qd->qd_change;
 382         gfs2_assert_warn(sdp, qd->qd_slot_count);
 383         qd->qd_slot_count++;
 384
 385         spin_unlock(&sdp->sd_quota_spin);
 386
 387         gfs2_assert_warn(sdp, qd->qd_change_sync);
 388         if (bh_get(qd)) {
 389                 clear_bit(QDF_LOCKED, &qd->qd_flags);
 390                 slot_put(qd);
 391                 qd_put(qd);
 392                 return 0;
 393         }
 394
 395         return 1;
 396 }
 397
 398 static void qd_unlock(struct gfs2_quota_data *qd)
 399 {
 400         gfs2_assert_warn(qd->qd_gl->gl_sbd,
 401                          test_bit(QDF_LOCKED, &qd->qd_flags));
 402         clear_bit(QDF_LOCKED, &qd->qd_flags);
 403         bh_put(qd);
 404         slot_put(qd);
 405         qd_put(qd);
 406 }
 407
 408 static int qdsb_get(struct gfs2_sbd *sdp, int user, u32 id, int create,
 409                     struct gfs2_quota_data **qdp)
 410 {
 411         int error;
 412
 413         error = qd_get(sdp, user, id, create, qdp);
 414         if (error)
 415                 return error;
 416
 417         error = slot_get(*qdp);
 418         if (error)
 419                 goto fail;
 420
 421         error = bh_get(*qdp);
 422         if (error)
 423                 goto fail_slot;
 424
 425         return 0;
 426
 427 fail_slot:
 428         slot_put(*qdp);
 429 fail:
 430         qd_put(*qdp);
 431         return error;
 432 }
 433
 434 static void qdsb_put(struct gfs2_quota_data *qd)
 435 {
 436         bh_put(qd);
 437         slot_put(qd);
 438         qd_put(qd);
 439 }
 440
 441 int gfs2_quota_hold(struct gfs2_inode *ip, u32 uid, u32 gid)
 442 {
 443         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 444         struct gfs2_alloc *al = &ip->i_alloc;
 445         struct gfs2_quota_data **qd = al->al_qd;
 446         int error;
 447
 448         if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
 449             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
 450                 return -EIO;
 451
 452         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 453                 return 0;
 454
 455         error = qdsb_get(sdp, QUOTA_USER, ip->i_di.di_uid, CREATE, qd);
 456         if (error)
 457                 goto out;
 458         al->al_qd_num++;
 459         qd++;
 460
 461         error = qdsb_get(sdp, QUOTA_GROUP, ip->i_di.di_gid, CREATE, qd);
 462         if (error)
 463                 goto out;
 464         al->al_qd_num++;
 465         qd++;
 466
 467         if (uid != NO_QUOTA_CHANGE && uid != ip->i_di.di_uid) {
 468                 error = qdsb_get(sdp, QUOTA_USER, uid, CREATE, qd);
 469                 if (error)
 470                         goto out;
 471                 al->al_qd_num++;
 472                 qd++;
 473         }
 474
 475         if (gid != NO_QUOTA_CHANGE && gid != ip->i_di.di_gid) {
 476                 error = qdsb_get(sdp, QUOTA_GROUP, gid, CREATE, qd);
 477                 if (error)
 478                         goto out;
 479                 al->al_qd_num++;
 480                 qd++;
 481         }
 482
 483 out:
 484         if (error)
 485                 gfs2_quota_unhold(ip);
 486         return error;
 487 }
 488
 489 void gfs2_quota_unhold(struct gfs2_inode *ip)
 490 {
 491         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 492         struct gfs2_alloc *al = &ip->i_alloc;
 493         unsigned int x;
 494
 495         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 496
 497         for (x = 0; x < al->al_qd_num; x++) {
 498                 qdsb_put(al->al_qd[x]);
 499                 al->al_qd[x] = NULL;
 500         }
 501         al->al_qd_num = 0;
 502 }
 503
 504 static int sort_qd(const void *a, const void *b)
 505 {
 506         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
 507         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
 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                         return -1;
 513                 else
 514                         return 1;
 515         }
 516         if (qd_a->qd_id < qd_b->qd_id)
 517                 return -1;
 518         if (qd_a->qd_id > qd_b->qd_id)
 519                 return 1;
 520
 521         return 0;
 522 }
 523
 524 static void do_qc(struct gfs2_quota_data *qd, s64 change)
 525 {
 526         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 527         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 528         struct gfs2_quota_change *qc = qd->qd_bh_qc;
 529         s64 x;
 530
 531         mutex_lock(&sdp->sd_quota_mutex);
 532         gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
 533
 534         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
 535                 qc->qc_change = 0;
 536                 qc->qc_flags = 0;
 537                 if (test_bit(QDF_USER, &qd->qd_flags))
 538                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
 539                 qc->qc_id = cpu_to_be32(qd->qd_id);
 540         }
 541
 542         x = qc->qc_change;
 543         x = be64_to_cpu(x) + change;
 544         qc->qc_change = cpu_to_be64(x);
 545
 546         spin_lock(&sdp->sd_quota_spin);
 547         qd->qd_change = x;
 548         spin_unlock(&sdp->sd_quota_spin);
 549
 550         if (!x) {
 551                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
 552                 clear_bit(QDF_CHANGE, &qd->qd_flags);
 553                 qc->qc_flags = 0;
 554                 qc->qc_id = 0;
 555                 slot_put(qd);
 556                 qd_put(qd);
 557         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
 558                 qd_hold(qd);
 559                 slot_hold(qd);
 560         }
 561
 562         mutex_unlock(&sdp->sd_quota_mutex);
 563 }
 564
 565 /**
 566  * gfs2_adjust_quota
 567  *
 568  * This function was mostly borrowed from gfs2_block_truncate_page which was
 569  * in turn mostly borrowed from ext3
 570  */
 571 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 572                              s64 change, struct gfs2_quota_data *qd)
 573 {
 574         struct inode *inode = &ip->i_inode;
 575         struct address_space *mapping = inode->i_mapping;
 576         unsigned long index = loc >> PAGE_CACHE_SHIFT;
 577         unsigned offset = loc & (PAGE_CACHE_SHIFT - 1);
 578         unsigned blocksize, iblock, pos;
 579         struct buffer_head *bh;
 580         struct page *page;
 581         void *kaddr;
 582         __be64 *ptr;
 583         s64 value;
 584         int err = -EIO;
 585
 586         page = grab_cache_page(mapping, index);
 587         if (!page)
 588                 return -ENOMEM;
 589
 590         blocksize = inode->i_sb->s_blocksize;
 591         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
 592
 593         if (!page_has_buffers(page))
 594                 create_empty_buffers(page, blocksize, 0);
 595
 596         bh = page_buffers(page);
 597         pos = blocksize;
 598         while (offset >= pos) {
 599                 bh = bh->b_this_page;
 600                 iblock++;
 601                 pos += blocksize;
 602         }
 603
 604         if (!buffer_mapped(bh)) {
 605                 gfs2_get_block(inode, iblock, bh, 1);
 606                 if (!buffer_mapped(bh))
 607                         goto unlock;
 608         }
 609
 610         if (PageUptodate(page))
 611                 set_buffer_uptodate(bh);
 612
 613         if (!buffer_uptodate(bh)) {
 614                 ll_rw_block(READ, 1, &bh);
 615                 wait_on_buffer(bh);
 616                 if (!buffer_uptodate(bh))
 617                         goto unlock;
 618         }
 619
 620         gfs2_trans_add_bh(ip->i_gl, bh, 0);
 621
 622         kaddr = kmap_atomic(page, KM_USER0);
 623         ptr = kaddr + offset;
 624         value = (s64)be64_to_cpu(*ptr) + change;
 625         *ptr = cpu_to_be64(value);
 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         qd->qd_qb.qb_value = cpu_to_be64(value);
 631 unlock:
 632         unlock_page(page);
 633         page_cache_release(page);
 634         return err;
 635 }
 636
 637 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 638 {
 639         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
 640         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 641         unsigned int data_blocks, ind_blocks;
 642         struct gfs2_holder *ghs, i_gh;
 643         unsigned int qx, x;
 644         struct gfs2_quota_data *qd;
 645         loff_t offset;
 646         unsigned int nalloc = 0;
 647         struct gfs2_alloc *al = NULL;
 648         int error;
 649
 650         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 651                               &data_blocks, &ind_blocks);
 652
 653         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_KERNEL);
 654         if (!ghs)
 655                 return -ENOMEM;
 656
 657         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 658         for (qx = 0; qx < num_qd; qx++) {
 659                 error = gfs2_glock_nq_init(qda[qx]->qd_gl,
 660                                            LM_ST_EXCLUSIVE,
 661                                            GL_NOCACHE, &ghs[qx]);
 662                 if (error)
 663                         goto out;
 664         }
 665
 666         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 667         if (error)
 668                 goto out;
 669
 670         for (x = 0; x < num_qd; x++) {
 671                 int alloc_required;
 672
 673                 offset = qd2offset(qda[x]);
 674                 error = gfs2_write_alloc_required(ip, offset,
 675                                                   sizeof(struct gfs2_quota),
 676                                                   &alloc_required);
 677                 if (error)
 678                         goto out_gunlock;
 679                 if (alloc_required)
 680                         nalloc++;
 681         }
 682
 683         if (nalloc) {
 684                 al = gfs2_alloc_get(ip);
 685
 686                 al->al_requested = nalloc * (data_blocks + ind_blocks);
 687
 688                 error = gfs2_inplace_reserve(ip);
 689                 if (error)
 690                         goto out_alloc;
 691
 692                 error = gfs2_trans_begin(sdp,
 693                                          al->al_rgd->rd_ri.ri_length +
 694                                          num_qd * data_blocks +
 695                                          nalloc * ind_blocks +
 696                                          RES_DINODE + num_qd +
 697                                          RES_STATFS, 0);
 698                 if (error)
 699                         goto out_ipres;
 700         } else {
 701                 error = gfs2_trans_begin(sdp,
 702                                          num_qd * data_blocks +
 703                                          RES_DINODE + num_qd, 0);
 704                 if (error)
 705                         goto out_gunlock;
 706         }
 707
 708         for (x = 0; x < num_qd; x++) {
 709                 qd = qda[x];
 710                 offset = qd2offset(qd);
 711                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync,
 712                                           (struct gfs2_quota_data *)
 713                                           qd->qd_gl->gl_lvb);
 714                 if (error)
 715                         goto out_end_trans;
 716
 717                 do_qc(qd, -qd->qd_change_sync);
 718         }
 719
 720         error = 0;
 721
 722 out_end_trans:
 723         gfs2_trans_end(sdp);
 724 out_ipres:
 725         if (nalloc)
 726                 gfs2_inplace_release(ip);
 727 out_alloc:
 728         if (nalloc)
 729                 gfs2_alloc_put(ip);
 730 out_gunlock:
 731         gfs2_glock_dq_uninit(&i_gh);
 732 out:
 733         while (qx--)
 734                 gfs2_glock_dq_uninit(&ghs[qx]);
 735         kfree(ghs);
 736         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
 737         return error;
 738 }
 739
 740 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 741                     struct gfs2_holder *q_gh)
 742 {
 743         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 744         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 745         struct gfs2_holder i_gh;
 746         struct gfs2_quota q;
 747         char buf[sizeof(struct gfs2_quota)];
 748         struct file_ra_state ra_state;
 749         int error;
 750         struct gfs2_quota_lvb *qlvb;
 751
 752         file_ra_state_init(&ra_state, sdp->sd_quota_inode->i_mapping);
 753 restart:
 754         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 755         if (error)
 756                 return error;
 757
 758         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 759
 760         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
 761                 loff_t pos;
 762                 gfs2_glock_dq_uninit(q_gh);
 763                 error = gfs2_glock_nq_init(qd->qd_gl,
 764                                           LM_ST_EXCLUSIVE, GL_NOCACHE,
 765                                           q_gh);
 766                 if (error)
 767                         return error;
 768
 769                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
 770                 if (error)
 771                         goto fail;
 772
 773                 memset(buf, 0, sizeof(struct gfs2_quota));
 774                 pos = qd2offset(qd);
 775                 error = gfs2_internal_read(ip, &ra_state, buf,
 776                                            &pos, sizeof(struct gfs2_quota));
 777                 if (error < 0)
 778                         goto fail_gunlock;
 779
 780                 gfs2_glock_dq_uninit(&i_gh);
 781
 782
 783                 gfs2_quota_in(&q, buf);
 784                 qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 785                 qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
 786                 qlvb->__pad = 0;
 787                 qlvb->qb_limit = cpu_to_be64(q.qu_limit);
 788                 qlvb->qb_warn = cpu_to_be64(q.qu_warn);
 789                 qlvb->qb_value = cpu_to_be64(q.qu_value);
 790                 qd->qd_qb = *qlvb;
 791
 792                 if (gfs2_glock_is_blocking(qd->qd_gl)) {
 793                         gfs2_glock_dq_uninit(q_gh);
 794                         force_refresh = 0;
 795                         goto restart;
 796                 }
 797         }
 798
 799         return 0;
 800
 801 fail_gunlock:
 802         gfs2_glock_dq_uninit(&i_gh);
 803 fail:
 804         gfs2_glock_dq_uninit(q_gh);
 805         return error;
 806 }
 807
 808 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
 809 {
 810         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 811         struct gfs2_alloc *al = &ip->i_alloc;
 812         unsigned int x;
 813         int error = 0;
 814
 815         gfs2_quota_hold(ip, uid, gid);
 816
 817         if (capable(CAP_SYS_RESOURCE) ||
 818             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 819                 return 0;
 820
 821         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
 822              sort_qd, NULL);
 823
 824         for (x = 0; x < al->al_qd_num; x++) {
 825                 error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
 826                 if (error)
 827                         break;
 828         }
 829
 830         if (!error)
 831                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
 832         else {
 833                 while (x--)
 834                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 835                 gfs2_quota_unhold(ip);
 836         }
 837
 838         return error;
 839 }
 840
 841 static int need_sync(struct gfs2_quota_data *qd)
 842 {
 843         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 844         struct gfs2_tune *gt = &sdp->sd_tune;
 845         s64 value;
 846         unsigned int num, den;
 847         int do_sync = 1;
 848
 849         if (!qd->qd_qb.qb_limit)
 850                 return 0;
 851
 852         spin_lock(&sdp->sd_quota_spin);
 853         value = qd->qd_change;
 854         spin_unlock(&sdp->sd_quota_spin);
 855
 856         spin_lock(&gt->gt_spin);
 857         num = gt->gt_quota_scale_num;
 858         den = gt->gt_quota_scale_den;
 859         spin_unlock(&gt->gt_spin);
 860
 861         if (value < 0)
 862                 do_sync = 0;
 863         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
 864                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 865                 do_sync = 0;
 866         else {
 867                 value *= gfs2_jindex_size(sdp) * num;
 868                 do_div(value, den);
 869                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
 870                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 871                         do_sync = 0;
 872         }
 873
 874         return do_sync;
 875 }
 876
 877 void gfs2_quota_unlock(struct gfs2_inode *ip)
 878 {
 879         struct gfs2_alloc *al = &ip->i_alloc;
 880         struct gfs2_quota_data *qda[4];
 881         unsigned int count = 0;
 882         unsigned int x;
 883
 884         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
 885                 goto out;
 886
 887         for (x = 0; x < al->al_qd_num; x++) {
 888                 struct gfs2_quota_data *qd;
 889                 int sync;
 890
 891                 qd = al->al_qd[x];
 892                 sync = need_sync(qd);
 893
 894                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 895
 896                 if (sync && qd_trylock(qd))
 897                         qda[count++] = qd;
 898         }
 899
 900         if (count) {
 901                 do_sync(count, qda);
 902                 for (x = 0; x < count; x++)
 903                         qd_unlock(qda[x]);
 904         }
 905
 906 out:
 907         gfs2_quota_unhold(ip);
 908 }
 909
 910 #define MAX_LINE 256
 911
 912 static int print_message(struct gfs2_quota_data *qd, char *type)
 913 {
 914         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 915
 916         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\r\n",
 917                sdp->sd_fsname, type,
 918                (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
 919                qd->qd_id);
 920
 921         return 0;
 922 }
 923
 924 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
 925 {
 926         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 927         struct gfs2_alloc *al = &ip->i_alloc;
 928         struct gfs2_quota_data *qd;
 929         s64 value;
 930         unsigned int x;
 931         int error = 0;
 932
 933         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
 934                 return 0;
 935
 936         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 937                 return 0;
 938
 939         for (x = 0; x < al->al_qd_num; x++) {
 940                 qd = al->al_qd[x];
 941
 942                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
 943                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
 944                         continue;
 945
 946                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
 947                 spin_lock(&sdp->sd_quota_spin);
 948                 value += qd->qd_change;
 949                 spin_unlock(&sdp->sd_quota_spin);
 950
 951                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
 952                         print_message(qd, "exceeded");
 953                         error = -EDQUOT;
 954                         break;
 955                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
 956                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
 957                            time_after_eq(jiffies, qd->qd_last_warn +
 958                                          gfs2_tune_get(sdp,
 959                                                 gt_quota_warn_period) * HZ)) {
 960                         error = print_message(qd, "warning");
 961                         qd->qd_last_warn = jiffies;
 962                 }
 963         }
 964
 965         return error;
 966 }
 967
 968 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
 969                        u32 uid, u32 gid)
 970 {
 971         struct gfs2_alloc *al = &ip->i_alloc;
 972         struct gfs2_quota_data *qd;
 973         unsigned int x;
 974         unsigned int found = 0;
 975
 976         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
 977                 return;
 978         if (ip->i_di.di_flags & GFS2_DIF_SYSTEM)
 979                 return;
 980
 981         for (x = 0; x < al->al_qd_num; x++) {
 982                 qd = al->al_qd[x];
 983
 984                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
 985                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
 986                         do_qc(qd, change);
 987                         found++;
 988                 }
 989         }
 990 }
 991
 992 int gfs2_quota_sync(struct gfs2_sbd *sdp)
 993 {
 994         struct gfs2_quota_data **qda;
 995         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
 996         unsigned int num_qd;
 997         unsigned int x;
 998         int error = 0;
 999
1000         sdp->sd_quota_sync_gen++;
1001
1002         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1003         if (!qda)
1004                 return -ENOMEM;
1005
1006         do {
1007                 num_qd = 0;
1008
1009                 for (;;) {
1010                         error = qd_fish(sdp, qda + num_qd);
1011                         if (error || !qda[num_qd])
1012                                 break;
1013                         if (++num_qd == max_qd)
1014                                 break;
1015                 }
1016
1017                 if (num_qd) {
1018                         if (!error)
1019                                 error = do_sync(num_qd, qda);
1020                         if (!error)
1021                                 for (x = 0; x < num_qd; x++)
1022                                         qda[x]->qd_sync_gen =
1023                                                 sdp->sd_quota_sync_gen;
1024
1025                         for (x = 0; x < num_qd; x++)
1026                                 qd_unlock(qda[x]);
1027                 }
1028         } while (!error && num_qd == max_qd);
1029
1030         kfree(qda);
1031
1032         return error;
1033 }
1034
1035 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1036 {
1037         struct gfs2_quota_data *qd;
1038         struct gfs2_holder q_gh;
1039         int error;
1040
1041         error = qd_get(sdp, user, id, CREATE, &qd);
1042         if (error)
1043                 return error;
1044
1045         error = do_glock(qd, FORCE, &q_gh);
1046         if (!error)
1047                 gfs2_glock_dq_uninit(&q_gh);
1048
1049         qd_put(qd);
1050
1051         return error;
1052 }
1053
1054 int gfs2_quota_init(struct gfs2_sbd *sdp)
1055 {
1056         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1057         unsigned int blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
1058         unsigned int x, slot = 0;
1059         unsigned int found = 0;
1060         u64 dblock;
1061         u32 extlen = 0;
1062         int error;
1063
1064         if (!ip->i_di.di_size ||
1065             ip->i_di.di_size > (64 << 20) ||
1066             ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1)) {
1067                 gfs2_consist_inode(ip);
1068                 return -EIO;
1069         }
1070         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1071         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1072
1073         error = -ENOMEM;
1074
1075         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1076                                        sizeof(unsigned char *), GFP_KERNEL);
1077         if (!sdp->sd_quota_bitmap)
1078                 return error;
1079
1080         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1081                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_KERNEL);
1082                 if (!sdp->sd_quota_bitmap[x])
1083                         goto fail;
1084         }
1085
1086         for (x = 0; x < blocks; x++) {
1087                 struct buffer_head *bh;
1088                 unsigned int y;
1089
1090                 if (!extlen) {
1091                         int new = 0;
1092                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1093                         if (error)
1094                                 goto fail;
1095                 }
1096                 gfs2_meta_ra(ip->i_gl,  dblock, extlen);
1097                 error = gfs2_meta_read(ip->i_gl, dblock, DIO_START | DIO_WAIT,
1098                                        &bh);
1099                 if (error)
1100                         goto fail;
1101                 error = -EIO;
1102                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1103                         brelse(bh);
1104                         goto fail;
1105                 }
1106
1107                 for (y = 0;
1108                      y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1109                      y++, slot++) {
1110                         struct gfs2_quota_change qc;
1111                         struct gfs2_quota_data *qd;
1112
1113                         gfs2_quota_change_in(&qc, bh->b_data +
1114                                           sizeof(struct gfs2_meta_header) +
1115                                           y * sizeof(struct gfs2_quota_change));
1116                         if (!qc.qc_change)
1117                                 continue;
1118
1119                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1120                                          qc.qc_id, &qd);
1121                         if (error) {
1122                                 brelse(bh);
1123                                 goto fail;
1124                         }
1125
1126                         set_bit(QDF_CHANGE, &qd->qd_flags);
1127                         qd->qd_change = qc.qc_change;
1128                         qd->qd_slot = slot;
1129                         qd->qd_slot_count = 1;
1130                         qd->qd_last_touched = jiffies;
1131
1132                         spin_lock(&sdp->sd_quota_spin);
1133                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1134                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1135                         atomic_inc(&sdp->sd_quota_count);
1136                         spin_unlock(&sdp->sd_quota_spin);
1137
1138                         found++;
1139                 }
1140
1141                 brelse(bh);
1142                 dblock++;
1143                 extlen--;
1144         }
1145
1146         if (found)
1147                 fs_info(sdp, "found %u quota changes\n", found);
1148
1149         return 0;
1150
1151 fail:
1152         gfs2_quota_cleanup(sdp);
1153         return error;
1154 }
1155
1156 void gfs2_quota_scan(struct gfs2_sbd *sdp)
1157 {
1158         struct gfs2_quota_data *qd, *safe;
1159         LIST_HEAD(dead);
1160
1161         spin_lock(&sdp->sd_quota_spin);
1162         list_for_each_entry_safe(qd, safe, &sdp->sd_quota_list, qd_list) {
1163                 if (!qd->qd_count &&
1164                     time_after_eq(jiffies, qd->qd_last_touched +
1165                                 gfs2_tune_get(sdp, gt_quota_cache_secs) * HZ)) {
1166                         list_move(&qd->qd_list, &dead);
1167                         gfs2_assert_warn(sdp,
1168                                          atomic_read(&sdp->sd_quota_count) > 0);
1169                         atomic_dec(&sdp->sd_quota_count);
1170                 }
1171         }
1172         spin_unlock(&sdp->sd_quota_spin);
1173
1174         while (!list_empty(&dead)) {
1175                 qd = list_entry(dead.next, struct gfs2_quota_data, qd_list);
1176                 list_del(&qd->qd_list);
1177
1178                 gfs2_assert_warn(sdp, !qd->qd_change);
1179                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1180                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1181
1182                 gfs2_lvb_unhold(qd->qd_gl);
1183                 kfree(qd);
1184         }
1185 }
1186
1187 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1188 {
1189         struct list_head *head = &sdp->sd_quota_list;
1190         struct gfs2_quota_data *qd;
1191         unsigned int x;
1192
1193         spin_lock(&sdp->sd_quota_spin);
1194         while (!list_empty(head)) {
1195                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1196
1197                 if (qd->qd_count > 1 ||
1198                     (qd->qd_count && !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1199                         list_move(&qd->qd_list, head);
1200                         spin_unlock(&sdp->sd_quota_spin);
1201                         schedule();
1202                         spin_lock(&sdp->sd_quota_spin);
1203                         continue;
1204                 }
1205
1206                 list_del(&qd->qd_list);
1207                 atomic_dec(&sdp->sd_quota_count);
1208                 spin_unlock(&sdp->sd_quota_spin);
1209
1210                 if (!qd->qd_count) {
1211                         gfs2_assert_warn(sdp, !qd->qd_change);
1212                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1213                 } else
1214                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1215                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1216
1217                 gfs2_lvb_unhold(qd->qd_gl);
1218                 kfree(qd);
1219
1220                 spin_lock(&sdp->sd_quota_spin);
1221         }
1222         spin_unlock(&sdp->sd_quota_spin);
1223
1224         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1225
1226         if (sdp->sd_quota_bitmap) {
1227                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1228                         kfree(sdp->sd_quota_bitmap[x]);
1229                 kfree(sdp->sd_quota_bitmap);
1230         }
1231 }
1232