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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/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 struct gfs2_quota_host {
  70         u64 qu_limit;
  71         u64 qu_warn;
  72         s64 qu_value;
  73 };
  74
  75 struct gfs2_quota_change_host {
  76         u64 qc_change;
  77         u32 qc_flags; /* GFS2_QCF_... */
  78         u32 qc_id;
  79 };
  80
  81 static u64 qd2offset(struct gfs2_quota_data *qd)
  82 {
  83         u64 offset;
  84
  85         offset = 2 * (u64)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
  86         offset *= sizeof(struct gfs2_quota);
  87
  88         return offset;
  89 }
  90
  91 static int qd_alloc(struct gfs2_sbd *sdp, int user, u32 id,
  92                     struct gfs2_quota_data **qdp)
  93 {
  94         struct gfs2_quota_data *qd;
  95         int error;
  96
  97         qd = kzalloc(sizeof(struct gfs2_quota_data), GFP_KERNEL);
  98         if (!qd)
  99                 return -ENOMEM;
 100
 101         qd->qd_count = 1;
 102         qd->qd_id = id;
 103         if (user)
 104                 set_bit(QDF_USER, &qd->qd_flags);
 105         qd->qd_slot = -1;
 106
 107         error = gfs2_glock_get(sdp, 2 * (u64)id + !user,
 108                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
 109         if (error)
 110                 goto fail;
 111
 112         error = gfs2_lvb_hold(qd->qd_gl);
 113         gfs2_glock_put(qd->qd_gl);
 114         if (error)
 115                 goto fail;
 116
 117         *qdp = qd;
 118
 119         return 0;
 120
 121 fail:
 122         kfree(qd);
 123         return error;
 124 }
 125
 126 static int qd_get(struct gfs2_sbd *sdp, int user, u32 id, int create,
 127                   struct gfs2_quota_data **qdp)
 128 {
 129         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
 130         int error, found;
 131
 132         *qdp = NULL;
 133
 134         for (;;) {
 135                 found = 0;
 136                 spin_lock(&sdp->sd_quota_spin);
 137                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 138                         if (qd->qd_id == id &&
 139                             !test_bit(QDF_USER, &qd->qd_flags) == !user) {
 140                                 qd->qd_count++;
 141                                 found = 1;
 142                                 break;
 143                         }
 144                 }
 145
 146                 if (!found)
 147                         qd = NULL;
 148
 149                 if (!qd && new_qd) {
 150                         qd = new_qd;
 151                         list_add(&qd->qd_list, &sdp->sd_quota_list);
 152                         atomic_inc(&sdp->sd_quota_count);
 153                         new_qd = NULL;
 154                 }
 155
 156                 spin_unlock(&sdp->sd_quota_spin);
 157
 158                 if (qd || !create) {
 159                         if (new_qd) {
 160                                 gfs2_lvb_unhold(new_qd->qd_gl);
 161                                 kfree(new_qd);
 162                         }
 163                         *qdp = qd;
 164                         return 0;
 165                 }
 166
 167                 error = qd_alloc(sdp, user, id, &new_qd);
 168                 if (error)
 169                         return error;
 170         }
 171 }
 172
 173 static void qd_hold(struct gfs2_quota_data *qd)
 174 {
 175         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 176
 177         spin_lock(&sdp->sd_quota_spin);
 178         gfs2_assert(sdp, qd->qd_count);
 179         qd->qd_count++;
 180         spin_unlock(&sdp->sd_quota_spin);
 181 }
 182
 183 static void qd_put(struct gfs2_quota_data *qd)
 184 {
 185         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 186         spin_lock(&sdp->sd_quota_spin);
 187         gfs2_assert(sdp, qd->qd_count);
 188         if (!--qd->qd_count)
 189                 qd->qd_last_touched = jiffies;
 190         spin_unlock(&sdp->sd_quota_spin);
 191 }
 192
 193 static int slot_get(struct gfs2_quota_data *qd)
 194 {
 195         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 196         unsigned int c, o = 0, b;
 197         unsigned char byte = 0;
 198
 199         spin_lock(&sdp->sd_quota_spin);
 200
 201         if (qd->qd_slot_count++) {
 202                 spin_unlock(&sdp->sd_quota_spin);
 203                 return 0;
 204         }
 205
 206         for (c = 0; c < sdp->sd_quota_chunks; c++)
 207                 for (o = 0; o < PAGE_SIZE; o++) {
 208                         byte = sdp->sd_quota_bitmap[c][o];
 209                         if (byte != 0xFF)
 210                                 goto found;
 211                 }
 212
 213         goto fail;
 214
 215 found:
 216         for (b = 0; b < 8; b++)
 217                 if (!(byte & (1 << b)))
 218                         break;
 219         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
 220
 221         if (qd->qd_slot >= sdp->sd_quota_slots)
 222                 goto fail;
 223
 224         sdp->sd_quota_bitmap[c][o] |= 1 << b;
 225
 226         spin_unlock(&sdp->sd_quota_spin);
 227
 228         return 0;
 229
 230 fail:
 231         qd->qd_slot_count--;
 232         spin_unlock(&sdp->sd_quota_spin);
 233         return -ENOSPC;
 234 }
 235
 236 static void slot_hold(struct gfs2_quota_data *qd)
 237 {
 238         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 239
 240         spin_lock(&sdp->sd_quota_spin);
 241         gfs2_assert(sdp, qd->qd_slot_count);
 242         qd->qd_slot_count++;
 243         spin_unlock(&sdp->sd_quota_spin);
 244 }
 245
 246 static void slot_put(struct gfs2_quota_data *qd)
 247 {
 248         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 249
 250         spin_lock(&sdp->sd_quota_spin);
 251         gfs2_assert(sdp, qd->qd_slot_count);
 252         if (!--qd->qd_slot_count) {
 253                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
 254                 qd->qd_slot = -1;
 255         }
 256         spin_unlock(&sdp->sd_quota_spin);
 257 }
 258
 259 static int bh_get(struct gfs2_quota_data *qd)
 260 {
 261         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 262         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 263         unsigned int block, offset;
 264         struct buffer_head *bh;
 265         int error;
 266         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
 267
 268         mutex_lock(&sdp->sd_quota_mutex);
 269
 270         if (qd->qd_bh_count++) {
 271                 mutex_unlock(&sdp->sd_quota_mutex);
 272                 return 0;
 273         }
 274
 275         block = qd->qd_slot / sdp->sd_qc_per_block;
 276         offset = qd->qd_slot % sdp->sd_qc_per_block;;
 277
 278         bh_map.b_size = 1 << ip->i_inode.i_blkbits;
 279         error = gfs2_block_map(&ip->i_inode, block, 0, &bh_map);
 280         if (error)
 281                 goto fail;
 282         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
 283         if (error)
 284                 goto fail;
 285         error = -EIO;
 286         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
 287                 goto fail_brelse;
 288
 289         qd->qd_bh = bh;
 290         qd->qd_bh_qc = (struct gfs2_quota_change *)
 291                 (bh->b_data + sizeof(struct gfs2_meta_header) +
 292                  offset * sizeof(struct gfs2_quota_change));
 293
 294         mutex_unlock(&sdp->sd_quota_mutex);
 295
 296         return 0;
 297
 298 fail_brelse:
 299         brelse(bh);
 300 fail:
 301         qd->qd_bh_count--;
 302         mutex_unlock(&sdp->sd_quota_mutex);
 303         return error;
 304 }
 305
 306 static void bh_put(struct gfs2_quota_data *qd)
 307 {
 308         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 309
 310         mutex_lock(&sdp->sd_quota_mutex);
 311         gfs2_assert(sdp, qd->qd_bh_count);
 312         if (!--qd->qd_bh_count) {
 313                 brelse(qd->qd_bh);
 314                 qd->qd_bh = NULL;
 315                 qd->qd_bh_qc = NULL;
 316         }
 317         mutex_unlock(&sdp->sd_quota_mutex);
 318 }
 319
 320 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
 321 {
 322         struct gfs2_quota_data *qd = NULL;
 323         int error;
 324         int found = 0;
 325
 326         *qdp = NULL;
 327
 328         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 329                 return 0;
 330
 331         spin_lock(&sdp->sd_quota_spin);
 332
 333         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 334                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 335                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
 336                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
 337                         continue;
 338
 339                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 340
 341                 set_bit(QDF_LOCKED, &qd->qd_flags);
 342                 gfs2_assert_warn(sdp, qd->qd_count);
 343                 qd->qd_count++;
 344                 qd->qd_change_sync = qd->qd_change;
 345                 gfs2_assert_warn(sdp, qd->qd_slot_count);
 346                 qd->qd_slot_count++;
 347                 found = 1;
 348
 349                 break;
 350         }
 351
 352         if (!found)
 353                 qd = NULL;
 354
 355         spin_unlock(&sdp->sd_quota_spin);
 356
 357         if (qd) {
 358                 gfs2_assert_warn(sdp, qd->qd_change_sync);
 359                 error = bh_get(qd);
 360                 if (error) {
 361                         clear_bit(QDF_LOCKED, &qd->qd_flags);
 362                         slot_put(qd);
 363                         qd_put(qd);
 364                         return error;
 365                 }
 366         }
 367
 368         *qdp = qd;
 369
 370         return 0;
 371 }
 372
 373 static int qd_trylock(struct gfs2_quota_data *qd)
 374 {
 375         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 376
 377         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 378                 return 0;
 379
 380         spin_lock(&sdp->sd_quota_spin);
 381
 382         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 383             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
 384                 spin_unlock(&sdp->sd_quota_spin);
 385                 return 0;
 386         }
 387
 388         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 389
 390         set_bit(QDF_LOCKED, &qd->qd_flags);
 391         gfs2_assert_warn(sdp, qd->qd_count);
 392         qd->qd_count++;
 393         qd->qd_change_sync = qd->qd_change;
 394         gfs2_assert_warn(sdp, qd->qd_slot_count);
 395         qd->qd_slot_count++;
 396
 397         spin_unlock(&sdp->sd_quota_spin);
 398
 399         gfs2_assert_warn(sdp, qd->qd_change_sync);
 400         if (bh_get(qd)) {
 401                 clear_bit(QDF_LOCKED, &qd->qd_flags);
 402                 slot_put(qd);
 403                 qd_put(qd);
 404                 return 0;
 405         }
 406
 407         return 1;
 408 }
 409
 410 static void qd_unlock(struct gfs2_quota_data *qd)
 411 {
 412         gfs2_assert_warn(qd->qd_gl->gl_sbd,
 413                          test_bit(QDF_LOCKED, &qd->qd_flags));
 414         clear_bit(QDF_LOCKED, &qd->qd_flags);
 415         bh_put(qd);
 416         slot_put(qd);
 417         qd_put(qd);
 418 }
 419
 420 static int qdsb_get(struct gfs2_sbd *sdp, int user, u32 id, int create,
 421                     struct gfs2_quota_data **qdp)
 422 {
 423         int error;
 424
 425         error = qd_get(sdp, user, id, create, qdp);
 426         if (error)
 427                 return error;
 428
 429         error = slot_get(*qdp);
 430         if (error)
 431                 goto fail;
 432
 433         error = bh_get(*qdp);
 434         if (error)
 435                 goto fail_slot;
 436
 437         return 0;
 438
 439 fail_slot:
 440         slot_put(*qdp);
 441 fail:
 442         qd_put(*qdp);
 443         return error;
 444 }
 445
 446 static void qdsb_put(struct gfs2_quota_data *qd)
 447 {
 448         bh_put(qd);
 449         slot_put(qd);
 450         qd_put(qd);
 451 }
 452
 453 int gfs2_quota_hold(struct gfs2_inode *ip, u32 uid, u32 gid)
 454 {
 455         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 456         struct gfs2_alloc *al = &ip->i_alloc;
 457         struct gfs2_quota_data **qd = al->al_qd;
 458         int error;
 459
 460         if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
 461             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
 462                 return -EIO;
 463
 464         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 465                 return 0;
 466
 467         error = qdsb_get(sdp, QUOTA_USER, ip->i_inode.i_uid, CREATE, qd);
 468         if (error)
 469                 goto out;
 470         al->al_qd_num++;
 471         qd++;
 472
 473         error = qdsb_get(sdp, QUOTA_GROUP, ip->i_inode.i_gid, CREATE, qd);
 474         if (error)
 475                 goto out;
 476         al->al_qd_num++;
 477         qd++;
 478
 479         if (uid != NO_QUOTA_CHANGE && uid != ip->i_inode.i_uid) {
 480                 error = qdsb_get(sdp, QUOTA_USER, uid, CREATE, qd);
 481                 if (error)
 482                         goto out;
 483                 al->al_qd_num++;
 484                 qd++;
 485         }
 486
 487         if (gid != NO_QUOTA_CHANGE && gid != ip->i_inode.i_gid) {
 488                 error = qdsb_get(sdp, QUOTA_GROUP, gid, CREATE, qd);
 489                 if (error)
 490                         goto out;
 491                 al->al_qd_num++;
 492                 qd++;
 493         }
 494
 495 out:
 496         if (error)
 497                 gfs2_quota_unhold(ip);
 498         return error;
 499 }
 500
 501 void gfs2_quota_unhold(struct gfs2_inode *ip)
 502 {
 503         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 504         struct gfs2_alloc *al = &ip->i_alloc;
 505         unsigned int x;
 506
 507         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 508
 509         for (x = 0; x < al->al_qd_num; x++) {
 510                 qdsb_put(al->al_qd[x]);
 511                 al->al_qd[x] = NULL;
 512         }
 513         al->al_qd_num = 0;
 514 }
 515
 516 static int sort_qd(const void *a, const void *b)
 517 {
 518         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
 519         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
 520
 521         if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
 522             !test_bit(QDF_USER, &qd_b->qd_flags)) {
 523                 if (test_bit(QDF_USER, &qd_a->qd_flags))
 524                         return -1;
 525                 else
 526                         return 1;
 527         }
 528         if (qd_a->qd_id < qd_b->qd_id)
 529                 return -1;
 530         if (qd_a->qd_id > qd_b->qd_id)
 531                 return 1;
 532
 533         return 0;
 534 }
 535
 536 static void do_qc(struct gfs2_quota_data *qd, s64 change)
 537 {
 538         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 539         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 540         struct gfs2_quota_change *qc = qd->qd_bh_qc;
 541         s64 x;
 542
 543         mutex_lock(&sdp->sd_quota_mutex);
 544         gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
 545
 546         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
 547                 qc->qc_change = 0;
 548                 qc->qc_flags = 0;
 549                 if (test_bit(QDF_USER, &qd->qd_flags))
 550                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
 551                 qc->qc_id = cpu_to_be32(qd->qd_id);
 552         }
 553
 554         x = be64_to_cpu(qc->qc_change) + change;
 555         qc->qc_change = cpu_to_be64(x);
 556
 557         spin_lock(&sdp->sd_quota_spin);
 558         qd->qd_change = x;
 559         spin_unlock(&sdp->sd_quota_spin);
 560
 561         if (!x) {
 562                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
 563                 clear_bit(QDF_CHANGE, &qd->qd_flags);
 564                 qc->qc_flags = 0;
 565                 qc->qc_id = 0;
 566                 slot_put(qd);
 567                 qd_put(qd);
 568         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
 569                 qd_hold(qd);
 570                 slot_hold(qd);
 571         }
 572
 573         mutex_unlock(&sdp->sd_quota_mutex);
 574 }
 575
 576 static void gfs2_quota_in(struct gfs2_quota_host *qu, const void *buf)
 577 {
 578         const struct gfs2_quota *str = buf;
 579
 580         qu->qu_limit = be64_to_cpu(str->qu_limit);
 581         qu->qu_warn = be64_to_cpu(str->qu_warn);
 582         qu->qu_value = be64_to_cpu(str->qu_value);
 583 }
 584
 585 static void gfs2_quota_out(const struct gfs2_quota_host *qu, void *buf)
 586 {
 587         struct gfs2_quota *str = buf;
 588
 589         str->qu_limit = cpu_to_be64(qu->qu_limit);
 590         str->qu_warn = cpu_to_be64(qu->qu_warn);
 591         str->qu_value = cpu_to_be64(qu->qu_value);
 592         memset(&str->qu_reserved, 0, sizeof(str->qu_reserved));
 593 }
 594
 595 /**
 596  * gfs2_adjust_quota
 597  *
 598  * This function was mostly borrowed from gfs2_block_truncate_page which was
 599  * in turn mostly borrowed from ext3
 600  */
 601 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 602                              s64 change, struct gfs2_quota_data *qd)
 603 {
 604         struct inode *inode = &ip->i_inode;
 605         struct address_space *mapping = inode->i_mapping;
 606         unsigned long index = loc >> PAGE_CACHE_SHIFT;
 607         unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
 608         unsigned blocksize, iblock, pos;
 609         struct buffer_head *bh;
 610         struct page *page;
 611         void *kaddr;
 612         char *ptr;
 613         struct gfs2_quota_host qp;
 614         s64 value;
 615         int err = -EIO;
 616
 617         page = grab_cache_page(mapping, index);
 618         if (!page)
 619                 return -ENOMEM;
 620
 621         blocksize = inode->i_sb->s_blocksize;
 622         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
 623
 624         if (!page_has_buffers(page))
 625                 create_empty_buffers(page, blocksize, 0);
 626
 627         bh = page_buffers(page);
 628         pos = blocksize;
 629         while (offset >= pos) {
 630                 bh = bh->b_this_page;
 631                 iblock++;
 632                 pos += blocksize;
 633         }
 634
 635         if (!buffer_mapped(bh)) {
 636                 gfs2_get_block(inode, iblock, bh, 1);
 637                 if (!buffer_mapped(bh))
 638                         goto unlock;
 639         }
 640
 641         if (PageUptodate(page))
 642                 set_buffer_uptodate(bh);
 643
 644         if (!buffer_uptodate(bh)) {
 645                 ll_rw_block(READ_META, 1, &bh);
 646                 wait_on_buffer(bh);
 647                 if (!buffer_uptodate(bh))
 648                         goto unlock;
 649         }
 650
 651         gfs2_trans_add_bh(ip->i_gl, bh, 0);
 652
 653         kaddr = kmap_atomic(page, KM_USER0);
 654         ptr = kaddr + offset;
 655         gfs2_quota_in(&qp, ptr);
 656         qp.qu_value += change;
 657         value = qp.qu_value;
 658         gfs2_quota_out(&qp, ptr);
 659         flush_dcache_page(page);
 660         kunmap_atomic(kaddr, KM_USER0);
 661         err = 0;
 662         qd->qd_qb.qb_magic = cpu_to_be32(GFS2_MAGIC);
 663         qd->qd_qb.qb_value = cpu_to_be64(value);
 664         ((struct gfs2_quota_lvb*)(qd->qd_gl->gl_lvb))->qb_magic = cpu_to_be32(GFS2_MAGIC);
 665         ((struct gfs2_quota_lvb*)(qd->qd_gl->gl_lvb))->qb_value = cpu_to_be64(value);
 666 unlock:
 667         unlock_page(page);
 668         page_cache_release(page);
 669         return err;
 670 }
 671
 672 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 673 {
 674         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
 675         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 676         unsigned int data_blocks, ind_blocks;
 677         struct gfs2_holder *ghs, i_gh;
 678         unsigned int qx, x;
 679         struct gfs2_quota_data *qd;
 680         loff_t offset;
 681         unsigned int nalloc = 0;
 682         struct gfs2_alloc *al = NULL;
 683         int error;
 684
 685         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 686                               &data_blocks, &ind_blocks);
 687
 688         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_KERNEL);
 689         if (!ghs)
 690                 return -ENOMEM;
 691
 692         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 693         for (qx = 0; qx < num_qd; qx++) {
 694                 error = gfs2_glock_nq_init(qda[qx]->qd_gl,
 695                                            LM_ST_EXCLUSIVE,
 696                                            GL_NOCACHE, &ghs[qx]);
 697                 if (error)
 698                         goto out;
 699         }
 700
 701         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 702         if (error)
 703                 goto out;
 704
 705         for (x = 0; x < num_qd; x++) {
 706                 int alloc_required;
 707
 708                 offset = qd2offset(qda[x]);
 709                 error = gfs2_write_alloc_required(ip, offset,
 710                                                   sizeof(struct gfs2_quota),
 711                                                   &alloc_required);
 712                 if (error)
 713                         goto out_gunlock;
 714                 if (alloc_required)
 715                         nalloc++;
 716         }
 717
 718         if (nalloc) {
 719                 al = gfs2_alloc_get(ip);
 720
 721                 al->al_requested = nalloc * (data_blocks + ind_blocks);
 722
 723                 error = gfs2_inplace_reserve(ip);
 724                 if (error)
 725                         goto out_alloc;
 726
 727                 error = gfs2_trans_begin(sdp,
 728                                          al->al_rgd->rd_length +
 729                                          num_qd * data_blocks +
 730                                          nalloc * ind_blocks +
 731                                          RES_DINODE + num_qd +
 732                                          RES_STATFS, 0);
 733                 if (error)
 734                         goto out_ipres;
 735         } else {
 736                 error = gfs2_trans_begin(sdp,
 737                                          num_qd * data_blocks +
 738                                          RES_DINODE + num_qd, 0);
 739                 if (error)
 740                         goto out_gunlock;
 741         }
 742
 743         for (x = 0; x < num_qd; x++) {
 744                 qd = qda[x];
 745                 offset = qd2offset(qd);
 746                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync,
 747                                           (struct gfs2_quota_data *)
 748                                           qd);
 749                 if (error)
 750                         goto out_end_trans;
 751
 752                 do_qc(qd, -qd->qd_change_sync);
 753         }
 754
 755         error = 0;
 756
 757 out_end_trans:
 758         gfs2_trans_end(sdp);
 759 out_ipres:
 760         if (nalloc)
 761                 gfs2_inplace_release(ip);
 762 out_alloc:
 763         if (nalloc)
 764                 gfs2_alloc_put(ip);
 765 out_gunlock:
 766         gfs2_glock_dq_uninit(&i_gh);
 767 out:
 768         while (qx--)
 769                 gfs2_glock_dq_uninit(&ghs[qx]);
 770         kfree(ghs);
 771         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
 772         return error;
 773 }
 774
 775 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 776                     struct gfs2_holder *q_gh)
 777 {
 778         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 779         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 780         struct gfs2_holder i_gh;
 781         struct gfs2_quota_host q;
 782         char buf[sizeof(struct gfs2_quota)];
 783         struct file_ra_state ra_state;
 784         int error;
 785         struct gfs2_quota_lvb *qlvb;
 786
 787         file_ra_state_init(&ra_state, sdp->sd_quota_inode->i_mapping);
 788 restart:
 789         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 790         if (error)
 791                 return error;
 792
 793         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 794
 795         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
 796                 loff_t pos;
 797                 gfs2_glock_dq_uninit(q_gh);
 798                 error = gfs2_glock_nq_init(qd->qd_gl,
 799                                           LM_ST_EXCLUSIVE, GL_NOCACHE,
 800                                           q_gh);
 801                 if (error)
 802                         return error;
 803
 804                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
 805                 if (error)
 806                         goto fail;
 807
 808                 memset(buf, 0, sizeof(struct gfs2_quota));
 809                 pos = qd2offset(qd);
 810                 error = gfs2_internal_read(ip, &ra_state, buf,
 811                                            &pos, sizeof(struct gfs2_quota));
 812                 if (error < 0)
 813                         goto fail_gunlock;
 814
 815                 gfs2_glock_dq_uninit(&i_gh);
 816
 817
 818                 gfs2_quota_in(&q, buf);
 819                 qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
 820                 qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
 821                 qlvb->__pad = 0;
 822                 qlvb->qb_limit = cpu_to_be64(q.qu_limit);
 823                 qlvb->qb_warn = cpu_to_be64(q.qu_warn);
 824                 qlvb->qb_value = cpu_to_be64(q.qu_value);
 825                 qd->qd_qb = *qlvb;
 826
 827                 if (gfs2_glock_is_blocking(qd->qd_gl)) {
 828                         gfs2_glock_dq_uninit(q_gh);
 829                         force_refresh = 0;
 830                         goto restart;
 831                 }
 832         }
 833
 834         return 0;
 835
 836 fail_gunlock:
 837         gfs2_glock_dq_uninit(&i_gh);
 838 fail:
 839         gfs2_glock_dq_uninit(q_gh);
 840         return error;
 841 }
 842
 843 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
 844 {
 845         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 846         struct gfs2_alloc *al = &ip->i_alloc;
 847         unsigned int x;
 848         int error = 0;
 849
 850         gfs2_quota_hold(ip, uid, gid);
 851
 852         if (capable(CAP_SYS_RESOURCE) ||
 853             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 854                 return 0;
 855
 856         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
 857              sort_qd, NULL);
 858
 859         for (x = 0; x < al->al_qd_num; x++) {
 860                 error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
 861                 if (error)
 862                         break;
 863         }
 864
 865         if (!error)
 866                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
 867         else {
 868                 while (x--)
 869                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 870                 gfs2_quota_unhold(ip);
 871         }
 872
 873         return error;
 874 }
 875
 876 static int need_sync(struct gfs2_quota_data *qd)
 877 {
 878         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 879         struct gfs2_tune *gt = &sdp->sd_tune;
 880         s64 value;
 881         unsigned int num, den;
 882         int do_sync = 1;
 883
 884         if (!qd->qd_qb.qb_limit)
 885                 return 0;
 886
 887         spin_lock(&sdp->sd_quota_spin);
 888         value = qd->qd_change;
 889         spin_unlock(&sdp->sd_quota_spin);
 890
 891         spin_lock(&gt->gt_spin);
 892         num = gt->gt_quota_scale_num;
 893         den = gt->gt_quota_scale_den;
 894         spin_unlock(&gt->gt_spin);
 895
 896         if (value < 0)
 897                 do_sync = 0;
 898         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
 899                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 900                 do_sync = 0;
 901         else {
 902                 value *= gfs2_jindex_size(sdp) * num;
 903                 do_div(value, den);
 904                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
 905                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 906                         do_sync = 0;
 907         }
 908
 909         return do_sync;
 910 }
 911
 912 void gfs2_quota_unlock(struct gfs2_inode *ip)
 913 {
 914         struct gfs2_alloc *al = &ip->i_alloc;
 915         struct gfs2_quota_data *qda[4];
 916         unsigned int count = 0;
 917         unsigned int x;
 918
 919         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
 920                 goto out;
 921
 922         for (x = 0; x < al->al_qd_num; x++) {
 923                 struct gfs2_quota_data *qd;
 924                 int sync;
 925
 926                 qd = al->al_qd[x];
 927                 sync = need_sync(qd);
 928
 929                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 930
 931                 if (sync && qd_trylock(qd))
 932                         qda[count++] = qd;
 933         }
 934
 935         if (count) {
 936                 do_sync(count, qda);
 937                 for (x = 0; x < count; x++)
 938                         qd_unlock(qda[x]);
 939         }
 940
 941 out:
 942         gfs2_quota_unhold(ip);
 943 }
 944
 945 #define MAX_LINE 256
 946
 947 static int print_message(struct gfs2_quota_data *qd, char *type)
 948 {
 949         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 950
 951         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\r\n",
 952                sdp->sd_fsname, type,
 953                (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
 954                qd->qd_id);
 955
 956         return 0;
 957 }
 958
 959 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
 960 {
 961         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 962         struct gfs2_alloc *al = &ip->i_alloc;
 963         struct gfs2_quota_data *qd;
 964         s64 value;
 965         unsigned int x;
 966         int error = 0;
 967
 968         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
 969                 return 0;
 970
 971         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 972                 return 0;
 973
 974         for (x = 0; x < al->al_qd_num; x++) {
 975                 qd = al->al_qd[x];
 976
 977                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
 978                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
 979                         continue;
 980
 981                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
 982                 spin_lock(&sdp->sd_quota_spin);
 983                 value += qd->qd_change;
 984                 spin_unlock(&sdp->sd_quota_spin);
 985
 986                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
 987                         print_message(qd, "exceeded");
 988                         error = -EDQUOT;
 989                         break;
 990                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
 991                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
 992                            time_after_eq(jiffies, qd->qd_last_warn +
 993                                          gfs2_tune_get(sdp,
 994                                                 gt_quota_warn_period) * HZ)) {
 995                         error = print_message(qd, "warning");
 996                         qd->qd_last_warn = jiffies;
 997                 }
 998         }
 999
1000         return error;
1001 }
1002
1003 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1004                        u32 uid, u32 gid)
1005 {
1006         struct gfs2_alloc *al = &ip->i_alloc;
1007         struct gfs2_quota_data *qd;
1008         unsigned int x;
1009         unsigned int found = 0;
1010
1011         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1012                 return;
1013         if (ip->i_di.di_flags & GFS2_DIF_SYSTEM)
1014                 return;
1015
1016         for (x = 0; x < al->al_qd_num; x++) {
1017                 qd = al->al_qd[x];
1018
1019                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1020                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
1021                         do_qc(qd, change);
1022                         found++;
1023                 }
1024         }
1025 }
1026
1027 int gfs2_quota_sync(struct gfs2_sbd *sdp)
1028 {
1029         struct gfs2_quota_data **qda;
1030         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1031         unsigned int num_qd;
1032         unsigned int x;
1033         int error = 0;
1034
1035         sdp->sd_quota_sync_gen++;
1036
1037         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1038         if (!qda)
1039                 return -ENOMEM;
1040
1041         do {
1042                 num_qd = 0;
1043
1044                 for (;;) {
1045                         error = qd_fish(sdp, qda + num_qd);
1046                         if (error || !qda[num_qd])
1047                                 break;
1048                         if (++num_qd == max_qd)
1049                                 break;
1050                 }
1051
1052                 if (num_qd) {
1053                         if (!error)
1054                                 error = do_sync(num_qd, qda);
1055                         if (!error)
1056                                 for (x = 0; x < num_qd; x++)
1057                                         qda[x]->qd_sync_gen =
1058                                                 sdp->sd_quota_sync_gen;
1059
1060                         for (x = 0; x < num_qd; x++)
1061                                 qd_unlock(qda[x]);
1062                 }
1063         } while (!error && num_qd == max_qd);
1064
1065         kfree(qda);
1066
1067         return error;
1068 }
1069
1070 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1071 {
1072         struct gfs2_quota_data *qd;
1073         struct gfs2_holder q_gh;
1074         int error;
1075
1076         error = qd_get(sdp, user, id, CREATE, &qd);
1077         if (error)
1078                 return error;
1079
1080         error = do_glock(qd, FORCE, &q_gh);
1081         if (!error)
1082                 gfs2_glock_dq_uninit(&q_gh);
1083
1084         qd_put(qd);
1085
1086         return error;
1087 }
1088
1089 static void gfs2_quota_change_in(struct gfs2_quota_change_host *qc, const void *buf)
1090 {
1091         const struct gfs2_quota_change *str = buf;
1092
1093         qc->qc_change = be64_to_cpu(str->qc_change);
1094         qc->qc_flags = be32_to_cpu(str->qc_flags);
1095         qc->qc_id = be32_to_cpu(str->qc_id);
1096 }
1097
1098 int gfs2_quota_init(struct gfs2_sbd *sdp)
1099 {
1100         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1101         unsigned int blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
1102         unsigned int x, slot = 0;
1103         unsigned int found = 0;
1104         u64 dblock;
1105         u32 extlen = 0;
1106         int error;
1107
1108         if (!ip->i_di.di_size || ip->i_di.di_size > (64 << 20) ||
1109             ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1)) {
1110                 gfs2_consist_inode(ip);
1111                 return -EIO;
1112         }
1113         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1114         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1115
1116         error = -ENOMEM;
1117
1118         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1119                                        sizeof(unsigned char *), GFP_KERNEL);
1120         if (!sdp->sd_quota_bitmap)
1121                 return error;
1122
1123         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1124                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_KERNEL);
1125                 if (!sdp->sd_quota_bitmap[x])
1126                         goto fail;
1127         }
1128
1129         for (x = 0; x < blocks; x++) {
1130                 struct buffer_head *bh;
1131                 unsigned int y;
1132
1133                 if (!extlen) {
1134                         int new = 0;
1135                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1136                         if (error)
1137                                 goto fail;
1138                 }
1139                 error = -EIO;
1140                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1141                 if (!bh)
1142                         goto fail;
1143                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1144                         brelse(bh);
1145                         goto fail;
1146                 }
1147
1148                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1149                      y++, slot++) {
1150                         struct gfs2_quota_change_host qc;
1151                         struct gfs2_quota_data *qd;
1152
1153                         gfs2_quota_change_in(&qc, bh->b_data +
1154                                           sizeof(struct gfs2_meta_header) +
1155                                           y * sizeof(struct gfs2_quota_change));
1156                         if (!qc.qc_change)
1157                                 continue;
1158
1159                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1160                                          qc.qc_id, &qd);
1161                         if (error) {
1162                                 brelse(bh);
1163                                 goto fail;
1164                         }
1165
1166                         set_bit(QDF_CHANGE, &qd->qd_flags);
1167                         qd->qd_change = qc.qc_change;
1168                         qd->qd_slot = slot;
1169                         qd->qd_slot_count = 1;
1170                         qd->qd_last_touched = jiffies;
1171
1172                         spin_lock(&sdp->sd_quota_spin);
1173                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1174                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1175                         atomic_inc(&sdp->sd_quota_count);
1176                         spin_unlock(&sdp->sd_quota_spin);
1177
1178                         found++;
1179                 }
1180
1181                 brelse(bh);
1182                 dblock++;
1183                 extlen--;
1184         }
1185
1186         if (found)
1187                 fs_info(sdp, "found %u quota changes\n", found);
1188
1189         return 0;
1190
1191 fail:
1192         gfs2_quota_cleanup(sdp);
1193         return error;
1194 }
1195
1196 void gfs2_quota_scan(struct gfs2_sbd *sdp)
1197 {
1198         struct gfs2_quota_data *qd, *safe;
1199         LIST_HEAD(dead);
1200
1201         spin_lock(&sdp->sd_quota_spin);
1202         list_for_each_entry_safe(qd, safe, &sdp->sd_quota_list, qd_list) {
1203                 if (!qd->qd_count &&
1204                     time_after_eq(jiffies, qd->qd_last_touched +
1205                                 gfs2_tune_get(sdp, gt_quota_cache_secs) * HZ)) {
1206                         list_move(&qd->qd_list, &dead);
1207                         gfs2_assert_warn(sdp,
1208                                          atomic_read(&sdp->sd_quota_count) > 0);
1209                         atomic_dec(&sdp->sd_quota_count);
1210                 }
1211         }
1212         spin_unlock(&sdp->sd_quota_spin);
1213
1214         while (!list_empty(&dead)) {
1215                 qd = list_entry(dead.next, struct gfs2_quota_data, qd_list);
1216                 list_del(&qd->qd_list);
1217
1218                 gfs2_assert_warn(sdp, !qd->qd_change);
1219                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1220                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1221
1222                 gfs2_lvb_unhold(qd->qd_gl);
1223                 kfree(qd);
1224         }
1225 }
1226
1227 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1228 {
1229         struct list_head *head = &sdp->sd_quota_list;
1230         struct gfs2_quota_data *qd;
1231         unsigned int x;
1232
1233         spin_lock(&sdp->sd_quota_spin);
1234         while (!list_empty(head)) {
1235                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1236
1237                 if (qd->qd_count > 1 ||
1238                     (qd->qd_count && !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1239                         list_move(&qd->qd_list, head);
1240                         spin_unlock(&sdp->sd_quota_spin);
1241                         schedule();
1242                         spin_lock(&sdp->sd_quota_spin);
1243                         continue;
1244                 }
1245
1246                 list_del(&qd->qd_list);
1247                 atomic_dec(&sdp->sd_quota_count);
1248                 spin_unlock(&sdp->sd_quota_spin);
1249
1250                 if (!qd->qd_count) {
1251                         gfs2_assert_warn(sdp, !qd->qd_change);
1252                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1253                 } else
1254                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1255                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1256
1257                 gfs2_lvb_unhold(qd->qd_gl);
1258                 kfree(qd);
1259
1260                 spin_lock(&sdp->sd_quota_spin);
1261         }
1262         spin_unlock(&sdp->sd_quota_spin);
1263
1264         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1265
1266         if (sdp->sd_quota_bitmap) {
1267                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1268                         kfree(sdp->sd_quota_bitmap[x]);
1269                 kfree(sdp->sd_quota_bitmap);
1270         }
1271 }
1272