fs/gfs2/quota.c

   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/bio.h>
  47 #include <linux/gfs2_ondisk.h>
  48 #include <linux/lm_interface.h>
  49
  50 #include "gfs2.h"
  51 #include "incore.h"
  52 #include "bmap.h"
  53 #include "glock.h"
  54 #include "glops.h"
  55 #include "log.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 u64 qd2offset(struct gfs2_quota_data *qd)
  70 {
  71         u64 offset;
  72
  73         offset = 2 * (u64)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, u32 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 * (u64)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, u32 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         struct buffer_head *bh;
 253         int error;
 254         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
 255
 256         mutex_lock(&sdp->sd_quota_mutex);
 257
 258         if (qd->qd_bh_count++) {
 259                 mutex_unlock(&sdp->sd_quota_mutex);
 260                 return 0;
 261         }
 262
 263         block = qd->qd_slot / sdp->sd_qc_per_block;
 264         offset = qd->qd_slot % sdp->sd_qc_per_block;;
 265
 266         bh_map.b_size = 1 << ip->i_inode.i_blkbits;
 267         error = gfs2_block_map(&ip->i_inode, block, 0, &bh_map);
 268         if (error)
 269                 goto fail;
 270         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, 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_unlock(&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_inode.i_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_inode.i_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_inode.i_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_inode.i_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 = be64_to_cpu(qc->qc_change) + change;
 543         qc->qc_change = cpu_to_be64(x);
 544
 545         spin_lock(&sdp->sd_quota_spin);
 546         qd->qd_change = x;
 547         spin_unlock(&sdp->sd_quota_spin);
 548
 549         if (!x) {
 550                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
 551                 clear_bit(QDF_CHANGE, &qd->qd_flags);
 552                 qc->qc_flags = 0;
 553                 qc->qc_id = 0;
 554                 slot_put(qd);
 555                 qd_put(qd);
 556         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
 557                 qd_hold(qd);
 558                 slot_hold(qd);
 559         }
 560
 561         mutex_unlock(&sdp->sd_quota_mutex);
 562 }
 563
 564 /**
 565  * gfs2_adjust_quota
 566  *
 567  * This function was mostly borrowed from gfs2_block_truncate_page which was
 568  * in turn mostly borrowed from ext3
 569  */
 570 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 571                              s64 change, struct gfs2_quota_data *qd)
 572 {
 573         struct inode *inode = &ip->i_inode;
 574         struct address_space *mapping = inode->i_mapping;
 575         unsigned long index = loc >> PAGE_CACHE_SHIFT;
 576         unsigned offset = loc & (PAGE_CACHE_SHIFT - 1);
 577         unsigned blocksize, iblock, pos;
 578         struct buffer_head *bh;
 579         struct page *page;
 580         void *kaddr;
 581         __be64 *ptr;
 582         s64 value;
 583         int err = -EIO;
 584
 585         page = grab_cache_page(mapping, index);
 586         if (!page)
 587                 return -ENOMEM;
 588
 589         blocksize = inode->i_sb->s_blocksize;
 590         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
 591
 592         if (!page_has_buffers(page))
 593                 create_empty_buffers(page, blocksize, 0);
 594
 595         bh = page_buffers(page);
 596         pos = blocksize;
 597         while (offset >= pos) {
 598                 bh = bh->b_this_page;
 599                 iblock++;
 600                 pos += blocksize;
 601         }
 602
 603         if (!buffer_mapped(bh)) {
 604                 gfs2_get_block(inode, iblock, bh, 1);
 605                 if (!buffer_mapped(bh))
 606                         goto unlock;
 607         }
 608
 609         if (PageUptodate(page))
 610                 set_buffer_uptodate(bh);
 611
 612         if (!buffer_uptodate(bh)) {
 613                 ll_rw_block(READ_META, 1, &bh);
 614                 wait_on_buffer(bh);
 615                 if (!buffer_uptodate(bh))
 616                         goto unlock;
 617         }
 618
 619         gfs2_trans_add_bh(ip->i_gl, bh, 0);
 620
 621         kaddr = kmap_atomic(page, KM_USER0);
 622         ptr = kaddr + offset;
 623         value = (s64)be64_to_cpu(*ptr) + change;
 624         *ptr = cpu_to_be64(value);
 625         flush_dcache_page(page);
 626         kunmap_atomic(kaddr, KM_USER0);
 627         err = 0;
 628         qd->qd_qb.qb_magic = cpu_to_be32(GFS2_MAGIC);
 629         qd->qd_qb.qb_value = cpu_to_be64(value);
 630 unlock:
 631         unlock_page(page);
 632         page_cache_release(page);
 633         return err;
 634 }
 635
 636 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 637 {
 638         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
 639         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 640         unsigned int data_blocks, ind_blocks;
 641         struct gfs2_holder *ghs, i_gh;
 642         unsigned int qx, x;
 643         struct gfs2_quota_data *qd;
 644         loff_t offset;
 645         unsigned int nalloc = 0;
 646         struct gfs2_alloc *al = NULL;
 647         int error;
 648
 649         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 650                               &data_blocks, &ind_blocks);
 651
 652         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_KERNEL);
 653         if (!ghs)
 654                 return -ENOMEM;
 655
 656         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 657         for (qx = 0; qx < num_qd; qx++) {
 658                 error = gfs2_glock_nq_init(qda[qx]->qd_gl,
 659                                            LM_ST_EXCLUSIVE,
 660                                            GL_NOCACHE, &ghs[qx]);
 661                 if (error)
 662                         goto out;
 663         }
 664
 665         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 666         if (error)
 667                 goto out;
 668
 669         for (x = 0; x < num_qd; x++) {
 670                 int alloc_required;
 671
 672                 offset = qd2offset(qda[x]);
 673                 error = gfs2_write_alloc_required(ip, offset,
 674                                                   sizeof(struct gfs2_quota),
 675                                                   &alloc_required);
 676                 if (error)
 677                         goto out_gunlock;
 678                 if (alloc_required)
 679                         nalloc++;
 680         }
 681
 682         if (nalloc) {
 683                 al = gfs2_alloc_get(ip);
 684
 685                 al->al_requested = nalloc * (data_blocks + ind_blocks);
 686
 687                 error = gfs2_inplace_reserve(ip);
 688                 if (error)
 689                         goto out_alloc;
 690
 691                 error = gfs2_trans_begin(sdp,
 692                                          al->al_rgd->rd_ri.ri_length +
 693                                          num_qd * data_blocks +
 694                                          nalloc * ind_blocks +
 695                                          RES_DINODE + num_qd +
 696                                          RES_STATFS, 0);
 697                 if (error)
 698                         goto out_ipres;
 699         } else {
 700                 error = gfs2_trans_begin(sdp,
 701                                          num_qd * data_blocks +
 702                                          RES_DINODE + num_qd, 0);
 703                 if (error)
 704                         goto out_gunlock;
 705         }
 706
 707         for (x = 0; x < num_qd; x++) {
 708                 qd = qda[x];
 709                 offset = qd2offset(qd);
 710                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync,
 711                                           (struct gfs2_quota_data *)
 712                                           qd->qd_gl->gl_lvb);
 713                 if (error)
 714                         goto out_end_trans;
 715
 716                 do_qc(qd, -qd->qd_change_sync);
 717         }
 718
 719         error = 0;
 720
 721 out_end_trans:
 722         gfs2_trans_end(sdp);
 723 out_ipres:
 724         if (nalloc)
 725                 gfs2_inplace_release(ip);
 726 out_alloc:
 727         if (nalloc)
 728                 gfs2_alloc_put(ip);
 729 out_gunlock:
 730         gfs2_glock_dq_uninit(&i_gh);
 731 out:
 732         while (qx--)
 733                 gfs2_glock_dq_uninit(&ghs[qx]);
 734         kfree(ghs);
 735         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
 736         return error;
 737 }
 738
 739 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 740                     struct gfs2_holder *q_gh)
 741 {
 742         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 743         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 744         struct gfs2_holder i_gh;
 745         struct gfs2_quota_host q;
 746         char buf[sizeof(struct gfs2_quota)];
 747         struct file_ra_state ra_state;
 748         int error;
 749         struct gfs2_quota_lvb *qlvb;
 750
 751         file_ra_state_init(&ra_state, sdp->sd_quota_inode->i_mapping);
 752 restart:
 753         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 754         if (error)
 755                 return error;
 756
 757         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 758
 759         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
 760                 loff_t pos;
 761                 gfs2_glock_dq_uninit(q_gh);
 762                 error = gfs2_glock_nq_init(qd->qd_gl,
 763                                           LM_ST_EXCLUSIVE, GL_NOCACHE,
 764                                           q_gh);
 765                 if (error)
 766                         return error;
 767
 768                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
 769                 if (error)
 770                         goto fail;
 771
 772                 memset(buf, 0, sizeof(struct gfs2_quota));
 773                 pos = qd2offset(qd);
 774                 error = gfs2_internal_read(ip, &ra_state, buf,
 775                                            &pos, sizeof(struct gfs2_quota));
 776                 if (error < 0)
 777                         goto fail_gunlock;
 778
 779                 gfs2_glock_dq_uninit(&i_gh);
 780
 781
 782                 gfs2_quota_in(&q, buf);
 783                 qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 784                 qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
 785                 qlvb->__pad = 0;
 786                 qlvb->qb_limit = cpu_to_be64(q.qu_limit);
 787                 qlvb->qb_warn = cpu_to_be64(q.qu_warn);
 788                 qlvb->qb_value = cpu_to_be64(q.qu_value);
 789                 qd->qd_qb = *qlvb;
 790
 791                 if (gfs2_glock_is_blocking(qd->qd_gl)) {
 792                         gfs2_glock_dq_uninit(q_gh);
 793                         force_refresh = 0;
 794                         goto restart;
 795                 }
 796         }
 797
 798         return 0;
 799
 800 fail_gunlock:
 801         gfs2_glock_dq_uninit(&i_gh);
 802 fail:
 803         gfs2_glock_dq_uninit(q_gh);
 804         return error;
 805 }
 806
 807 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
 808 {
 809         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 810         struct gfs2_alloc *al = &ip->i_alloc;
 811         unsigned int x;
 812         int error = 0;
 813
 814         gfs2_quota_hold(ip, uid, gid);
 815
 816         if (capable(CAP_SYS_RESOURCE) ||
 817             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 818                 return 0;
 819
 820         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
 821              sort_qd, NULL);
 822
 823         for (x = 0; x < al->al_qd_num; x++) {
 824                 error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
 825                 if (error)
 826                         break;
 827         }
 828
 829         if (!error)
 830                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
 831         else {
 832                 while (x--)
 833                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 834                 gfs2_quota_unhold(ip);
 835         }
 836
 837         return error;
 838 }
 839
 840 static int need_sync(struct gfs2_quota_data *qd)
 841 {
 842         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 843         struct gfs2_tune *gt = &sdp->sd_tune;
 844         s64 value;
 845         unsigned int num, den;
 846         int do_sync = 1;
 847
 848         if (!qd->qd_qb.qb_limit)
 849                 return 0;
 850
 851         spin_lock(&sdp->sd_quota_spin);
 852         value = qd->qd_change;
 853         spin_unlock(&sdp->sd_quota_spin);
 854
 855         spin_lock(&gt->gt_spin);
 856         num = gt->gt_quota_scale_num;
 857         den = gt->gt_quota_scale_den;
 858         spin_unlock(&gt->gt_spin);
 859
 860         if (value < 0)
 861                 do_sync = 0;
 862         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
 863                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 864                 do_sync = 0;
 865         else {
 866                 value *= gfs2_jindex_size(sdp) * num;
 867                 do_div(value, den);
 868                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
 869                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 870                         do_sync = 0;
 871         }
 872
 873         return do_sync;
 874 }
 875
 876 void gfs2_quota_unlock(struct gfs2_inode *ip)
 877 {
 878         struct gfs2_alloc *al = &ip->i_alloc;
 879         struct gfs2_quota_data *qda[4];
 880         unsigned int count = 0;
 881         unsigned int x;
 882
 883         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
 884                 goto out;
 885
 886         for (x = 0; x < al->al_qd_num; x++) {
 887                 struct gfs2_quota_data *qd;
 888                 int sync;
 889
 890                 qd = al->al_qd[x];
 891                 sync = need_sync(qd);
 892
 893                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 894
 895                 if (sync && qd_trylock(qd))
 896                         qda[count++] = qd;
 897         }
 898
 899         if (count) {
 900                 do_sync(count, qda);
 901                 for (x = 0; x < count; x++)
 902                         qd_unlock(qda[x]);
 903         }
 904
 905 out:
 906         gfs2_quota_unhold(ip);
 907 }
 908
 909 #define MAX_LINE 256
 910
 911 static int print_message(struct gfs2_quota_data *qd, char *type)
 912 {
 913         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 914
 915         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\r\n",
 916                sdp->sd_fsname, type,
 917                (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
 918                qd->qd_id);
 919
 920         return 0;
 921 }
 922
 923 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
 924 {
 925         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 926         struct gfs2_alloc *al = &ip->i_alloc;
 927         struct gfs2_quota_data *qd;
 928         s64 value;
 929         unsigned int x;
 930         int error = 0;
 931
 932         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
 933                 return 0;
 934
 935         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 936                 return 0;
 937
 938         for (x = 0; x < al->al_qd_num; x++) {
 939                 qd = al->al_qd[x];
 940
 941                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
 942                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
 943                         continue;
 944
 945                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
 946                 spin_lock(&sdp->sd_quota_spin);
 947                 value += qd->qd_change;
 948                 spin_unlock(&sdp->sd_quota_spin);
 949
 950                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
 951                         print_message(qd, "exceeded");
 952                         error = -EDQUOT;
 953                         break;
 954                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
 955                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
 956                            time_after_eq(jiffies, qd->qd_last_warn +
 957                                          gfs2_tune_get(sdp,
 958                                                 gt_quota_warn_period) * HZ)) {
 959                         error = print_message(qd, "warning");
 960                         qd->qd_last_warn = jiffies;
 961                 }
 962         }
 963
 964         return error;
 965 }
 966
 967 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
 968                        u32 uid, u32 gid)
 969 {
 970         struct gfs2_alloc *al = &ip->i_alloc;
 971         struct gfs2_quota_data *qd;
 972         unsigned int x;
 973         unsigned int found = 0;
 974
 975         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
 976                 return;
 977         if (ip->i_di.di_flags & GFS2_DIF_SYSTEM)
 978                 return;
 979
 980         for (x = 0; x < al->al_qd_num; x++) {
 981                 qd = al->al_qd[x];
 982
 983                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
 984                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
 985                         do_qc(qd, change);
 986                         found++;
 987                 }
 988         }
 989 }
 990
 991 int gfs2_quota_sync(struct gfs2_sbd *sdp)
 992 {
 993         struct gfs2_quota_data **qda;
 994         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
 995         unsigned int num_qd;
 996         unsigned int x;
 997         int error = 0;
 998
 999         sdp->sd_quota_sync_gen++;
1000
1001         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1002         if (!qda)
1003                 return -ENOMEM;
1004
1005         do {
1006                 num_qd = 0;
1007
1008                 for (;;) {
1009                         error = qd_fish(sdp, qda + num_qd);
1010                         if (error || !qda[num_qd])
1011                                 break;
1012                         if (++num_qd == max_qd)
1013                                 break;
1014                 }
1015
1016                 if (num_qd) {
1017                         if (!error)
1018                                 error = do_sync(num_qd, qda);
1019                         if (!error)
1020                                 for (x = 0; x < num_qd; x++)
1021                                         qda[x]->qd_sync_gen =
1022                                                 sdp->sd_quota_sync_gen;
1023
1024                         for (x = 0; x < num_qd; x++)
1025                                 qd_unlock(qda[x]);
1026                 }
1027         } while (!error && num_qd == max_qd);
1028
1029         kfree(qda);
1030
1031         return error;
1032 }
1033
1034 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1035 {
1036         struct gfs2_quota_data *qd;
1037         struct gfs2_holder q_gh;
1038         int error;
1039
1040         error = qd_get(sdp, user, id, CREATE, &qd);
1041         if (error)
1042                 return error;
1043
1044         error = do_glock(qd, FORCE, &q_gh);
1045         if (!error)
1046                 gfs2_glock_dq_uninit(&q_gh);
1047
1048         qd_put(qd);
1049
1050         return error;
1051 }
1052
1053 int gfs2_quota_init(struct gfs2_sbd *sdp)
1054 {
1055         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1056         unsigned int blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
1057         unsigned int x, slot = 0;
1058         unsigned int found = 0;
1059         u64 dblock;
1060         u32 extlen = 0;
1061         int error;
1062
1063         if (!ip->i_di.di_size || ip->i_di.di_size > (64 << 20) ||
1064             ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1)) {
1065                 gfs2_consist_inode(ip);
1066                 return -EIO;
1067         }
1068         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1069         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1070
1071         error = -ENOMEM;
1072
1073         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1074                                        sizeof(unsigned char *), GFP_KERNEL);
1075         if (!sdp->sd_quota_bitmap)
1076                 return error;
1077
1078         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1079                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_KERNEL);
1080                 if (!sdp->sd_quota_bitmap[x])
1081                         goto fail;
1082         }
1083
1084         for (x = 0; x < blocks; x++) {
1085                 struct buffer_head *bh;
1086                 unsigned int y;
1087
1088                 if (!extlen) {
1089                         int new = 0;
1090                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1091                         if (error)
1092                                 goto fail;
1093                 }
1094                 error = -EIO;
1095                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1096                 if (!bh)
1097                         goto fail;
1098                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1099                         brelse(bh);
1100                         goto fail;
1101                 }
1102
1103                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1104                      y++, slot++) {
1105                         struct gfs2_quota_change_host qc;
1106                         struct gfs2_quota_data *qd;
1107
1108                         gfs2_quota_change_in(&qc, bh->b_data +
1109                                           sizeof(struct gfs2_meta_header) +
1110                                           y * sizeof(struct gfs2_quota_change));
1111                         if (!qc.qc_change)
1112                                 continue;
1113
1114                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1115                                          qc.qc_id, &qd);
1116                         if (error) {
1117                                 brelse(bh);
1118                                 goto fail;
1119                         }
1120
1121                         set_bit(QDF_CHANGE, &qd->qd_flags);
1122                         qd->qd_change = qc.qc_change;
1123                         qd->qd_slot = slot;
1124                         qd->qd_slot_count = 1;
1125                         qd->qd_last_touched = jiffies;
1126
1127                         spin_lock(&sdp->sd_quota_spin);
1128                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1129                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1130                         atomic_inc(&sdp->sd_quota_count);
1131                         spin_unlock(&sdp->sd_quota_spin);
1132
1133                         found++;
1134                 }
1135
1136                 brelse(bh);
1137                 dblock++;
1138                 extlen--;
1139         }
1140
1141         if (found)
1142                 fs_info(sdp, "found %u quota changes\n", found);
1143
1144         return 0;
1145
1146 fail:
1147         gfs2_quota_cleanup(sdp);
1148         return error;
1149 }
1150
1151 void gfs2_quota_scan(struct gfs2_sbd *sdp)
1152 {
1153         struct gfs2_quota_data *qd, *safe;
1154         LIST_HEAD(dead);
1155
1156         spin_lock(&sdp->sd_quota_spin);
1157         list_for_each_entry_safe(qd, safe, &sdp->sd_quota_list, qd_list) {
1158                 if (!qd->qd_count &&
1159                     time_after_eq(jiffies, qd->qd_last_touched +
1160                                 gfs2_tune_get(sdp, gt_quota_cache_secs) * HZ)) {
1161                         list_move(&qd->qd_list, &dead);
1162                         gfs2_assert_warn(sdp,
1163                                          atomic_read(&sdp->sd_quota_count) > 0);
1164                         atomic_dec(&sdp->sd_quota_count);
1165                 }
1166         }
1167         spin_unlock(&sdp->sd_quota_spin);
1168
1169         while (!list_empty(&dead)) {
1170                 qd = list_entry(dead.next, struct gfs2_quota_data, qd_list);
1171                 list_del(&qd->qd_list);
1172
1173                 gfs2_assert_warn(sdp, !qd->qd_change);
1174                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1175                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1176
1177                 gfs2_lvb_unhold(qd->qd_gl);
1178                 kfree(qd);
1179         }
1180 }
1181
1182 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1183 {
1184         struct list_head *head = &sdp->sd_quota_list;
1185         struct gfs2_quota_data *qd;
1186         unsigned int x;
1187
1188         spin_lock(&sdp->sd_quota_spin);
1189         while (!list_empty(head)) {
1190                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1191
1192                 if (qd->qd_count > 1 ||
1193                     (qd->qd_count && !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1194                         list_move(&qd->qd_list, head);
1195                         spin_unlock(&sdp->sd_quota_spin);
1196                         schedule();
1197                         spin_lock(&sdp->sd_quota_spin);
1198                         continue;
1199                 }
1200
1201                 list_del(&qd->qd_list);
1202                 atomic_dec(&sdp->sd_quota_count);
1203                 spin_unlock(&sdp->sd_quota_spin);
1204
1205                 if (!qd->qd_count) {
1206                         gfs2_assert_warn(sdp, !qd->qd_change);
1207                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1208                 } else
1209                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1210                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1211
1212                 gfs2_lvb_unhold(qd->qd_gl);
1213                 kfree(qd);
1214
1215                 spin_lock(&sdp->sd_quota_spin);
1216         }
1217         spin_unlock(&sdp->sd_quota_spin);
1218
1219         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1220
1221         if (sdp->sd_quota_bitmap) {
1222                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1223                         kfree(sdp->sd_quota_bitmap[x]);
1224                 kfree(sdp->sd_quota_bitmap);
1225         }
1226 }
1227