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/gfs2_ondisk.h>
  47 #include <linux/lm_interface.h>
  48
  49 #include "gfs2.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         struct buffer_head *bh;
 252         int error;
 253         struct buffer_head bh_map;
 254
 255         mutex_lock(&sdp->sd_quota_mutex);
 256
 257         if (qd->qd_bh_count++) {
 258                 mutex_unlock(&sdp->sd_quota_mutex);
 259                 return 0;
 260         }
 261
 262         block = qd->qd_slot / sdp->sd_qc_per_block;
 263         offset = qd->qd_slot % sdp->sd_qc_per_block;;
 264
 265         error = gfs2_block_map(&ip->i_inode, block, 0, &bh_map, 1);
 266         if (error)
 267                 goto fail;
 268         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
 269         if (error)
 270                 goto fail;
 271         error = -EIO;
 272         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
 273                 goto fail_brelse;
 274
 275         qd->qd_bh = bh;
 276         qd->qd_bh_qc = (struct gfs2_quota_change *)
 277                 (bh->b_data + sizeof(struct gfs2_meta_header) +
 278                  offset * sizeof(struct gfs2_quota_change));
 279
 280         mutex_lock(&sdp->sd_quota_mutex);
 281
 282         return 0;
 283
 284 fail_brelse:
 285         brelse(bh);
 286 fail:
 287         qd->qd_bh_count--;
 288         mutex_unlock(&sdp->sd_quota_mutex);
 289         return error;
 290 }
 291
 292 static void bh_put(struct gfs2_quota_data *qd)
 293 {
 294         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 295
 296         mutex_lock(&sdp->sd_quota_mutex);
 297         gfs2_assert(sdp, qd->qd_bh_count);
 298         if (!--qd->qd_bh_count) {
 299                 brelse(qd->qd_bh);
 300                 qd->qd_bh = NULL;
 301                 qd->qd_bh_qc = NULL;
 302         }
 303         mutex_unlock(&sdp->sd_quota_mutex);
 304 }
 305
 306 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
 307 {
 308         struct gfs2_quota_data *qd = NULL;
 309         int error;
 310         int found = 0;
 311
 312         *qdp = NULL;
 313
 314         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 315                 return 0;
 316
 317         spin_lock(&sdp->sd_quota_spin);
 318
 319         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 320                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 321                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
 322                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
 323                         continue;
 324
 325                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 326
 327                 set_bit(QDF_LOCKED, &qd->qd_flags);
 328                 gfs2_assert_warn(sdp, qd->qd_count);
 329                 qd->qd_count++;
 330                 qd->qd_change_sync = qd->qd_change;
 331                 gfs2_assert_warn(sdp, qd->qd_slot_count);
 332                 qd->qd_slot_count++;
 333                 found = 1;
 334
 335                 break;
 336         }
 337
 338         if (!found)
 339                 qd = NULL;
 340
 341         spin_unlock(&sdp->sd_quota_spin);
 342
 343         if (qd) {
 344                 gfs2_assert_warn(sdp, qd->qd_change_sync);
 345                 error = bh_get(qd);
 346                 if (error) {
 347                         clear_bit(QDF_LOCKED, &qd->qd_flags);
 348                         slot_put(qd);
 349                         qd_put(qd);
 350                         return error;
 351                 }
 352         }
 353
 354         *qdp = qd;
 355
 356         return 0;
 357 }
 358
 359 static int qd_trylock(struct gfs2_quota_data *qd)
 360 {
 361         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 362
 363         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 364                 return 0;
 365
 366         spin_lock(&sdp->sd_quota_spin);
 367
 368         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 369             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
 370                 spin_unlock(&sdp->sd_quota_spin);
 371                 return 0;
 372         }
 373
 374         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 375
 376         set_bit(QDF_LOCKED, &qd->qd_flags);
 377         gfs2_assert_warn(sdp, qd->qd_count);
 378         qd->qd_count++;
 379         qd->qd_change_sync = qd->qd_change;
 380         gfs2_assert_warn(sdp, qd->qd_slot_count);
 381         qd->qd_slot_count++;
 382
 383         spin_unlock(&sdp->sd_quota_spin);
 384
 385         gfs2_assert_warn(sdp, qd->qd_change_sync);
 386         if (bh_get(qd)) {
 387                 clear_bit(QDF_LOCKED, &qd->qd_flags);
 388                 slot_put(qd);
 389                 qd_put(qd);
 390                 return 0;
 391         }
 392
 393         return 1;
 394 }
 395
 396 static void qd_unlock(struct gfs2_quota_data *qd)
 397 {
 398         gfs2_assert_warn(qd->qd_gl->gl_sbd,
 399                          test_bit(QDF_LOCKED, &qd->qd_flags));
 400         clear_bit(QDF_LOCKED, &qd->qd_flags);
 401         bh_put(qd);
 402         slot_put(qd);
 403         qd_put(qd);
 404 }
 405
 406 static int qdsb_get(struct gfs2_sbd *sdp, int user, u32 id, int create,
 407                     struct gfs2_quota_data **qdp)
 408 {
 409         int error;
 410
 411         error = qd_get(sdp, user, id, create, qdp);
 412         if (error)
 413                 return error;
 414
 415         error = slot_get(*qdp);
 416         if (error)
 417                 goto fail;
 418
 419         error = bh_get(*qdp);
 420         if (error)
 421                 goto fail_slot;
 422
 423         return 0;
 424
 425 fail_slot:
 426         slot_put(*qdp);
 427 fail:
 428         qd_put(*qdp);
 429         return error;
 430 }
 431
 432 static void qdsb_put(struct gfs2_quota_data *qd)
 433 {
 434         bh_put(qd);
 435         slot_put(qd);
 436         qd_put(qd);
 437 }
 438
 439 int gfs2_quota_hold(struct gfs2_inode *ip, u32 uid, u32 gid)
 440 {
 441         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 442         struct gfs2_alloc *al = &ip->i_alloc;
 443         struct gfs2_quota_data **qd = al->al_qd;
 444         int error;
 445
 446         if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
 447             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
 448                 return -EIO;
 449
 450         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 451                 return 0;
 452
 453         error = qdsb_get(sdp, QUOTA_USER, ip->i_di.di_uid, CREATE, qd);
 454         if (error)
 455                 goto out;
 456         al->al_qd_num++;
 457         qd++;
 458
 459         error = qdsb_get(sdp, QUOTA_GROUP, ip->i_di.di_gid, CREATE, qd);
 460         if (error)
 461                 goto out;
 462         al->al_qd_num++;
 463         qd++;
 464
 465         if (uid != NO_QUOTA_CHANGE && uid != ip->i_di.di_uid) {
 466                 error = qdsb_get(sdp, QUOTA_USER, uid, CREATE, qd);
 467                 if (error)
 468                         goto out;
 469                 al->al_qd_num++;
 470                 qd++;
 471         }
 472
 473         if (gid != NO_QUOTA_CHANGE && gid != ip->i_di.di_gid) {
 474                 error = qdsb_get(sdp, QUOTA_GROUP, gid, CREATE, qd);
 475                 if (error)
 476                         goto out;
 477                 al->al_qd_num++;
 478                 qd++;
 479         }
 480
 481 out:
 482         if (error)
 483                 gfs2_quota_unhold(ip);
 484         return error;
 485 }
 486
 487 void gfs2_quota_unhold(struct gfs2_inode *ip)
 488 {
 489         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 490         struct gfs2_alloc *al = &ip->i_alloc;
 491         unsigned int x;
 492
 493         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 494
 495         for (x = 0; x < al->al_qd_num; x++) {
 496                 qdsb_put(al->al_qd[x]);
 497                 al->al_qd[x] = NULL;
 498         }
 499         al->al_qd_num = 0;
 500 }
 501
 502 static int sort_qd(const void *a, const void *b)
 503 {
 504         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
 505         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
 506
 507         if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
 508             !test_bit(QDF_USER, &qd_b->qd_flags)) {
 509                 if (test_bit(QDF_USER, &qd_a->qd_flags))
 510                         return -1;
 511                 else
 512                         return 1;
 513         }
 514         if (qd_a->qd_id < qd_b->qd_id)
 515                 return -1;
 516         if (qd_a->qd_id > qd_b->qd_id)
 517                 return 1;
 518
 519         return 0;
 520 }
 521
 522 static void do_qc(struct gfs2_quota_data *qd, s64 change)
 523 {
 524         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 525         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 526         struct gfs2_quota_change *qc = qd->qd_bh_qc;
 527         s64 x;
 528
 529         mutex_lock(&sdp->sd_quota_mutex);
 530         gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
 531
 532         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
 533                 qc->qc_change = 0;
 534                 qc->qc_flags = 0;
 535                 if (test_bit(QDF_USER, &qd->qd_flags))
 536                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
 537                 qc->qc_id = cpu_to_be32(qd->qd_id);
 538         }
 539
 540         x = qc->qc_change;
 541         x = be64_to_cpu(x) + change;
 542         qc->qc_change = cpu_to_be64(x);
 543
 544         spin_lock(&sdp->sd_quota_spin);
 545         qd->qd_change = x;
 546         spin_unlock(&sdp->sd_quota_spin);
 547
 548         if (!x) {
 549                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
 550                 clear_bit(QDF_CHANGE, &qd->qd_flags);
 551                 qc->qc_flags = 0;
 552                 qc->qc_id = 0;
 553                 slot_put(qd);
 554                 qd_put(qd);
 555         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
 556                 qd_hold(qd);
 557                 slot_hold(qd);
 558         }
 559
 560         mutex_unlock(&sdp->sd_quota_mutex);
 561 }
 562
 563 /**
 564  * gfs2_adjust_quota
 565  *
 566  * This function was mostly borrowed from gfs2_block_truncate_page which was
 567  * in turn mostly borrowed from ext3
 568  */
 569 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 570                              s64 change, struct gfs2_quota_data *qd)
 571 {
 572         struct inode *inode = &ip->i_inode;
 573         struct address_space *mapping = inode->i_mapping;
 574         unsigned long index = loc >> PAGE_CACHE_SHIFT;
 575         unsigned offset = loc & (PAGE_CACHE_SHIFT - 1);
 576         unsigned blocksize, iblock, pos;
 577         struct buffer_head *bh;
 578         struct page *page;
 579         void *kaddr;
 580         __be64 *ptr;
 581         s64 value;
 582         int err = -EIO;
 583
 584         page = grab_cache_page(mapping, index);
 585         if (!page)
 586                 return -ENOMEM;
 587
 588         blocksize = inode->i_sb->s_blocksize;
 589         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
 590
 591         if (!page_has_buffers(page))
 592                 create_empty_buffers(page, blocksize, 0);
 593
 594         bh = page_buffers(page);
 595         pos = blocksize;
 596         while (offset >= pos) {
 597                 bh = bh->b_this_page;
 598                 iblock++;
 599                 pos += blocksize;
 600         }
 601
 602         if (!buffer_mapped(bh)) {
 603                 gfs2_get_block(inode, iblock, bh, 1);
 604                 if (!buffer_mapped(bh))
 605                         goto unlock;
 606         }
 607
 608         if (PageUptodate(page))
 609                 set_buffer_uptodate(bh);
 610
 611         if (!buffer_uptodate(bh)) {
 612                 ll_rw_block(READ, 1, &bh);
 613                 wait_on_buffer(bh);
 614                 if (!buffer_uptodate(bh))
 615                         goto unlock;
 616         }
 617
 618         gfs2_trans_add_bh(ip->i_gl, bh, 0);
 619
 620         kaddr = kmap_atomic(page, KM_USER0);
 621         ptr = kaddr + offset;
 622         value = (s64)be64_to_cpu(*ptr) + change;
 623         *ptr = cpu_to_be64(value);
 624         flush_dcache_page(page);
 625         kunmap_atomic(kaddr, KM_USER0);
 626         err = 0;
 627         qd->qd_qb.qb_magic = cpu_to_be32(GFS2_MAGIC);
 628         qd->qd_qb.qb_value = cpu_to_be64(value);
 629 unlock:
 630         unlock_page(page);
 631         page_cache_release(page);
 632         return err;
 633 }
 634
 635 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 636 {
 637         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
 638         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 639         unsigned int data_blocks, ind_blocks;
 640         struct gfs2_holder *ghs, i_gh;
 641         unsigned int qx, x;
 642         struct gfs2_quota_data *qd;
 643         loff_t offset;
 644         unsigned int nalloc = 0;
 645         struct gfs2_alloc *al = NULL;
 646         int error;
 647
 648         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 649                               &data_blocks, &ind_blocks);
 650
 651         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_KERNEL);
 652         if (!ghs)
 653                 return -ENOMEM;
 654
 655         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 656         for (qx = 0; qx < num_qd; qx++) {
 657                 error = gfs2_glock_nq_init(qda[qx]->qd_gl,
 658                                            LM_ST_EXCLUSIVE,
 659                                            GL_NOCACHE, &ghs[qx]);
 660                 if (error)
 661                         goto out;
 662         }
 663
 664         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 665         if (error)
 666                 goto out;
 667
 668         for (x = 0; x < num_qd; x++) {
 669                 int alloc_required;
 670
 671                 offset = qd2offset(qda[x]);
 672                 error = gfs2_write_alloc_required(ip, offset,
 673                                                   sizeof(struct gfs2_quota),
 674                                                   &alloc_required);
 675                 if (error)
 676                         goto out_gunlock;
 677                 if (alloc_required)
 678                         nalloc++;
 679         }
 680
 681         if (nalloc) {
 682                 al = gfs2_alloc_get(ip);
 683
 684                 al->al_requested = nalloc * (data_blocks + ind_blocks);
 685
 686                 error = gfs2_inplace_reserve(ip);
 687                 if (error)
 688                         goto out_alloc;
 689
 690                 error = gfs2_trans_begin(sdp,
 691                                          al->al_rgd->rd_ri.ri_length +
 692                                          num_qd * data_blocks +
 693                                          nalloc * ind_blocks +
 694                                          RES_DINODE + num_qd +
 695                                          RES_STATFS, 0);
 696                 if (error)
 697                         goto out_ipres;
 698         } else {
 699                 error = gfs2_trans_begin(sdp,
 700                                          num_qd * data_blocks +
 701                                          RES_DINODE + num_qd, 0);
 702                 if (error)
 703                         goto out_gunlock;
 704         }
 705
 706         for (x = 0; x < num_qd; x++) {
 707                 qd = qda[x];
 708                 offset = qd2offset(qd);
 709                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync,
 710                                           (struct gfs2_quota_data *)
 711                                           qd->qd_gl->gl_lvb);
 712                 if (error)
 713                         goto out_end_trans;
 714
 715                 do_qc(qd, -qd->qd_change_sync);
 716         }
 717
 718         error = 0;
 719
 720 out_end_trans:
 721         gfs2_trans_end(sdp);
 722 out_ipres:
 723         if (nalloc)
 724                 gfs2_inplace_release(ip);
 725 out_alloc:
 726         if (nalloc)
 727                 gfs2_alloc_put(ip);
 728 out_gunlock:
 729         gfs2_glock_dq_uninit(&i_gh);
 730 out:
 731         while (qx--)
 732                 gfs2_glock_dq_uninit(&ghs[qx]);
 733         kfree(ghs);
 734         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
 735         return error;
 736 }
 737
 738 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 739                     struct gfs2_holder *q_gh)
 740 {
 741         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 742         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 743         struct gfs2_holder i_gh;
 744         struct gfs2_quota q;
 745         char buf[sizeof(struct gfs2_quota)];
 746         struct file_ra_state ra_state;
 747         int error;
 748         struct gfs2_quota_lvb *qlvb;
 749
 750         file_ra_state_init(&ra_state, sdp->sd_quota_inode->i_mapping);
 751 restart:
 752         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 753         if (error)
 754                 return error;
 755
 756         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 757
 758         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
 759                 loff_t pos;
 760                 gfs2_glock_dq_uninit(q_gh);
 761                 error = gfs2_glock_nq_init(qd->qd_gl,
 762                                           LM_ST_EXCLUSIVE, GL_NOCACHE,
 763                                           q_gh);
 764                 if (error)
 765                         return error;
 766
 767                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
 768                 if (error)
 769                         goto fail;
 770
 771                 memset(buf, 0, sizeof(struct gfs2_quota));
 772                 pos = qd2offset(qd);
 773                 error = gfs2_internal_read(ip, &ra_state, buf,
 774                                            &pos, sizeof(struct gfs2_quota));
 775                 if (error < 0)
 776                         goto fail_gunlock;
 777
 778                 gfs2_glock_dq_uninit(&i_gh);
 779
 780
 781                 gfs2_quota_in(&q, buf);
 782                 qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 783                 qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
 784                 qlvb->__pad = 0;
 785                 qlvb->qb_limit = cpu_to_be64(q.qu_limit);
 786                 qlvb->qb_warn = cpu_to_be64(q.qu_warn);
 787                 qlvb->qb_value = cpu_to_be64(q.qu_value);
 788                 qd->qd_qb = *qlvb;
 789
 790                 if (gfs2_glock_is_blocking(qd->qd_gl)) {
 791                         gfs2_glock_dq_uninit(q_gh);
 792                         force_refresh = 0;
 793                         goto restart;
 794                 }
 795         }
 796
 797         return 0;
 798
 799 fail_gunlock:
 800         gfs2_glock_dq_uninit(&i_gh);
 801 fail:
 802         gfs2_glock_dq_uninit(q_gh);
 803         return error;
 804 }
 805
 806 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
 807 {
 808         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 809         struct gfs2_alloc *al = &ip->i_alloc;
 810         unsigned int x;
 811         int error = 0;
 812
 813         gfs2_quota_hold(ip, uid, gid);
 814
 815         if (capable(CAP_SYS_RESOURCE) ||
 816             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 817                 return 0;
 818
 819         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
 820              sort_qd, NULL);
 821
 822         for (x = 0; x < al->al_qd_num; x++) {
 823                 error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
 824                 if (error)
 825                         break;
 826         }
 827
 828         if (!error)
 829                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
 830         else {
 831                 while (x--)
 832                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 833                 gfs2_quota_unhold(ip);
 834         }
 835
 836         return error;
 837 }
 838
 839 static int need_sync(struct gfs2_quota_data *qd)
 840 {
 841         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 842         struct gfs2_tune *gt = &sdp->sd_tune;
 843         s64 value;
 844         unsigned int num, den;
 845         int do_sync = 1;
 846
 847         if (!qd->qd_qb.qb_limit)
 848                 return 0;
 849
 850         spin_lock(&sdp->sd_quota_spin);
 851         value = qd->qd_change;
 852         spin_unlock(&sdp->sd_quota_spin);
 853
 854         spin_lock(&gt->gt_spin);
 855         num = gt->gt_quota_scale_num;
 856         den = gt->gt_quota_scale_den;
 857         spin_unlock(&gt->gt_spin);
 858
 859         if (value < 0)
 860                 do_sync = 0;
 861         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
 862                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 863                 do_sync = 0;
 864         else {
 865                 value *= gfs2_jindex_size(sdp) * num;
 866                 do_div(value, den);
 867                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
 868                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 869                         do_sync = 0;
 870         }
 871
 872         return do_sync;
 873 }
 874
 875 void gfs2_quota_unlock(struct gfs2_inode *ip)
 876 {
 877         struct gfs2_alloc *al = &ip->i_alloc;
 878         struct gfs2_quota_data *qda[4];
 879         unsigned int count = 0;
 880         unsigned int x;
 881
 882         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
 883                 goto out;
 884
 885         for (x = 0; x < al->al_qd_num; x++) {
 886                 struct gfs2_quota_data *qd;
 887                 int sync;
 888
 889                 qd = al->al_qd[x];
 890                 sync = need_sync(qd);
 891
 892                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 893
 894                 if (sync && qd_trylock(qd))
 895                         qda[count++] = qd;
 896         }
 897
 898         if (count) {
 899                 do_sync(count, qda);
 900                 for (x = 0; x < count; x++)
 901                         qd_unlock(qda[x]);
 902         }
 903
 904 out:
 905         gfs2_quota_unhold(ip);
 906 }
 907
 908 #define MAX_LINE 256
 909
 910 static int print_message(struct gfs2_quota_data *qd, char *type)
 911 {
 912         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 913
 914         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\r\n",
 915                sdp->sd_fsname, type,
 916                (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
 917                qd->qd_id);
 918
 919         return 0;
 920 }
 921
 922 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
 923 {
 924         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 925         struct gfs2_alloc *al = &ip->i_alloc;
 926         struct gfs2_quota_data *qd;
 927         s64 value;
 928         unsigned int x;
 929         int error = 0;
 930
 931         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
 932                 return 0;
 933
 934         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 935                 return 0;
 936
 937         for (x = 0; x < al->al_qd_num; x++) {
 938                 qd = al->al_qd[x];
 939
 940                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
 941                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
 942                         continue;
 943
 944                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
 945                 spin_lock(&sdp->sd_quota_spin);
 946                 value += qd->qd_change;
 947                 spin_unlock(&sdp->sd_quota_spin);
 948
 949                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
 950                         print_message(qd, "exceeded");
 951                         error = -EDQUOT;
 952                         break;
 953                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
 954                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
 955                            time_after_eq(jiffies, qd->qd_last_warn +
 956                                          gfs2_tune_get(sdp,
 957                                                 gt_quota_warn_period) * HZ)) {
 958                         error = print_message(qd, "warning");
 959                         qd->qd_last_warn = jiffies;
 960                 }
 961         }
 962
 963         return error;
 964 }
 965
 966 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
 967                        u32 uid, u32 gid)
 968 {
 969         struct gfs2_alloc *al = &ip->i_alloc;
 970         struct gfs2_quota_data *qd;
 971         unsigned int x;
 972         unsigned int found = 0;
 973
 974         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
 975                 return;
 976         if (ip->i_di.di_flags & GFS2_DIF_SYSTEM)
 977                 return;
 978
 979         for (x = 0; x < al->al_qd_num; x++) {
 980                 qd = al->al_qd[x];
 981
 982                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
 983                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
 984                         do_qc(qd, change);
 985                         found++;
 986                 }
 987         }
 988 }
 989
 990 int gfs2_quota_sync(struct gfs2_sbd *sdp)
 991 {
 992         struct gfs2_quota_data **qda;
 993         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
 994         unsigned int num_qd;
 995         unsigned int x;
 996         int error = 0;
 997
 998         sdp->sd_quota_sync_gen++;
 999
1000         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1001         if (!qda)
1002                 return -ENOMEM;
1003
1004         do {
1005                 num_qd = 0;
1006
1007                 for (;;) {
1008                         error = qd_fish(sdp, qda + num_qd);
1009                         if (error || !qda[num_qd])
1010                                 break;
1011                         if (++num_qd == max_qd)
1012                                 break;
1013                 }
1014
1015                 if (num_qd) {
1016                         if (!error)
1017                                 error = do_sync(num_qd, qda);
1018                         if (!error)
1019                                 for (x = 0; x < num_qd; x++)
1020                                         qda[x]->qd_sync_gen =
1021                                                 sdp->sd_quota_sync_gen;
1022
1023                         for (x = 0; x < num_qd; x++)
1024                                 qd_unlock(qda[x]);
1025                 }
1026         } while (!error && num_qd == max_qd);
1027
1028         kfree(qda);
1029
1030         return error;
1031 }
1032
1033 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1034 {
1035         struct gfs2_quota_data *qd;
1036         struct gfs2_holder q_gh;
1037         int error;
1038
1039         error = qd_get(sdp, user, id, CREATE, &qd);
1040         if (error)
1041                 return error;
1042
1043         error = do_glock(qd, FORCE, &q_gh);
1044         if (!error)
1045                 gfs2_glock_dq_uninit(&q_gh);
1046
1047         qd_put(qd);
1048
1049         return error;
1050 }
1051
1052 int gfs2_quota_init(struct gfs2_sbd *sdp)
1053 {
1054         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1055         unsigned int blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
1056         unsigned int x, slot = 0;
1057         unsigned int found = 0;
1058         u64 dblock;
1059         u32 extlen = 0;
1060         int error;
1061
1062         if (!ip->i_di.di_size || ip->i_di.di_size > (64 << 20) ||
1063             ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1)) {
1064                 gfs2_consist_inode(ip);
1065                 return -EIO;
1066         }
1067         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1068         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1069
1070         error = -ENOMEM;
1071
1072         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1073                                        sizeof(unsigned char *), GFP_KERNEL);
1074         if (!sdp->sd_quota_bitmap)
1075                 return error;
1076
1077         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1078                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_KERNEL);
1079                 if (!sdp->sd_quota_bitmap[x])
1080                         goto fail;
1081         }
1082
1083         for (x = 0; x < blocks; x++) {
1084                 struct buffer_head *bh;
1085                 unsigned int y;
1086
1087                 if (!extlen) {
1088                         int new = 0;
1089                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1090                         if (error)
1091                                 goto fail;
1092                 }
1093                 error = -EIO;
1094                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1095                 if (!bh)
1096                         goto fail;
1097                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1098                         brelse(bh);
1099                         goto fail;
1100                 }
1101
1102                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1103                      y++, slot++) {
1104                         struct gfs2_quota_change qc;
1105                         struct gfs2_quota_data *qd;
1106
1107                         gfs2_quota_change_in(&qc, bh->b_data +
1108                                           sizeof(struct gfs2_meta_header) +
1109                                           y * sizeof(struct gfs2_quota_change));
1110                         if (!qc.qc_change)
1111                                 continue;
1112
1113                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1114                                          qc.qc_id, &qd);
1115                         if (error) {
1116                                 brelse(bh);
1117                                 goto fail;
1118                         }
1119
1120                         set_bit(QDF_CHANGE, &qd->qd_flags);
1121                         qd->qd_change = qc.qc_change;
1122                         qd->qd_slot = slot;
1123                         qd->qd_slot_count = 1;
1124                         qd->qd_last_touched = jiffies;
1125
1126                         spin_lock(&sdp->sd_quota_spin);
1127                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1128                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1129                         atomic_inc(&sdp->sd_quota_count);
1130                         spin_unlock(&sdp->sd_quota_spin);
1131
1132                         found++;
1133                 }
1134
1135                 brelse(bh);
1136                 dblock++;
1137                 extlen--;
1138         }
1139
1140         if (found)
1141                 fs_info(sdp, "found %u quota changes\n", found);
1142
1143         return 0;
1144
1145 fail:
1146         gfs2_quota_cleanup(sdp);
1147         return error;
1148 }
1149
1150 void gfs2_quota_scan(struct gfs2_sbd *sdp)
1151 {
1152         struct gfs2_quota_data *qd, *safe;
1153         LIST_HEAD(dead);
1154
1155         spin_lock(&sdp->sd_quota_spin);
1156         list_for_each_entry_safe(qd, safe, &sdp->sd_quota_list, qd_list) {
1157                 if (!qd->qd_count &&
1158                     time_after_eq(jiffies, qd->qd_last_touched +
1159                                 gfs2_tune_get(sdp, gt_quota_cache_secs) * HZ)) {
1160                         list_move(&qd->qd_list, &dead);
1161                         gfs2_assert_warn(sdp,
1162                                          atomic_read(&sdp->sd_quota_count) > 0);
1163                         atomic_dec(&sdp->sd_quota_count);
1164                 }
1165         }
1166         spin_unlock(&sdp->sd_quota_spin);
1167
1168         while (!list_empty(&dead)) {
1169                 qd = list_entry(dead.next, struct gfs2_quota_data, qd_list);
1170                 list_del(&qd->qd_list);
1171
1172                 gfs2_assert_warn(sdp, !qd->qd_change);
1173                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1174                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1175
1176                 gfs2_lvb_unhold(qd->qd_gl);
1177                 kfree(qd);
1178         }
1179 }
1180
1181 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1182 {
1183         struct list_head *head = &sdp->sd_quota_list;
1184         struct gfs2_quota_data *qd;
1185         unsigned int x;
1186
1187         spin_lock(&sdp->sd_quota_spin);
1188         while (!list_empty(head)) {
1189                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1190
1191                 if (qd->qd_count > 1 ||
1192                     (qd->qd_count && !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1193                         list_move(&qd->qd_list, head);
1194                         spin_unlock(&sdp->sd_quota_spin);
1195                         schedule();
1196                         spin_lock(&sdp->sd_quota_spin);
1197                         continue;
1198                 }
1199
1200                 list_del(&qd->qd_list);
1201                 atomic_dec(&sdp->sd_quota_count);
1202                 spin_unlock(&sdp->sd_quota_spin);
1203
1204                 if (!qd->qd_count) {
1205                         gfs2_assert_warn(sdp, !qd->qd_change);
1206                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1207                 } else
1208                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1209                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1210
1211                 gfs2_lvb_unhold(qd->qd_gl);
1212                 kfree(qd);
1213
1214                 spin_lock(&sdp->sd_quota_spin);
1215         }
1216         spin_unlock(&sdp->sd_quota_spin);
1217
1218         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1219
1220         if (sdp->sd_quota_bitmap) {
1221                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1222                         kfree(sdp->sd_quota_bitmap[x]);
1223                 kfree(sdp->sd_quota_bitmap);
1224         }
1225 }
1226