SAFE public projects git trees. - safe/jmp/linux-2.6/blob - fs/gfs2/quota.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2005 Red Hat, Inc.  All rights reserved.
   4  *
   5  * This copyrighted material is made available to anyone wishing to use,
   6  * modify, copy, or redistribute it subject to the terms and conditions
   7  * of the GNU General Public License v.2.
   8  */
   9
  10 /*
  11  * Quota change tags are associated with each transaction that allocates or
  12  * deallocates space.  Those changes are accumulated locally to each node (in a
  13  * per-node file) and then are periodically synced to the quota file.  This
  14  * avoids the bottleneck of constantly touching the quota file, but introduces
  15  * fuzziness in the current usage value of IDs that are being used on different
  16  * nodes in the cluster simultaneously.  So, it is possible for a user on
  17  * multiple nodes to overrun their quota, but that overrun is controlable.
  18  * Since quota tags are part of transactions, there is no need to a quota check
  19  * program to be run on node crashes or anything like that.
  20  *
  21  * There are couple of knobs that let the administrator manage the quota
  22  * fuzziness.  "quota_quantum" sets the maximum time a quota change can be
  23  * sitting on one node before being synced to the quota file.  (The default is
  24  * 60 seconds.)  Another knob, "quota_scale" controls how quickly the frequency
  25  * of quota file syncs increases as the user moves closer to their limit.  The
  26  * more frequent the syncs, the more accurate the quota enforcement, but that
  27  * means that there is more contention between the nodes for the quota file.
  28  * The default value is one.  This sets the maximum theoretical quota overrun
  29  * (with infinite node with infinite bandwidth) to twice the user's limit.  (In
  30  * practice, the maximum overrun you see should be much less.)  A "quota_scale"
  31  * number greater than one makes quota syncs more frequent and reduces the
  32  * maximum overrun.  Numbers less than one (but greater than zero) make quota
  33  * syncs less frequent.
  34  *
  35  * GFS quotas also use per-ID Lock Value Blocks (LVBs) to cache the contents of
  36  * the quota file, so it is not being constantly read.
  37  */
  38
  39 #include <linux/sched.h>
  40 #include <linux/slab.h>
  41 #include <linux/spinlock.h>
  42 #include <linux/completion.h>
  43 #include <linux/buffer_head.h>
  44 #include <linux/tty.h>
  45 #include <linux/sort.h>
  46 #include <asm/semaphore.h>
  47
  48 #include "gfs2.h"
  49 #include "bmap.h"
  50 #include "glock.h"
  51 #include "glops.h"
  52 #include "jdata.h"
  53 #include "log.h"
  54 #include "meta_io.h"
  55 #include "quota.h"
  56 #include "rgrp.h"
  57 #include "super.h"
  58 #include "trans.h"
  59 #include "ops_file.h"
  60
  61 #define QUOTA_USER 1
  62 #define QUOTA_GROUP 0
  63
  64 static uint64_t qd2offset(struct gfs2_quota_data *qd)
  65 {
  66         uint64_t offset;
  67
  68         offset = 2 * (uint64_t)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
  69         offset *= sizeof(struct gfs2_quota);
  70
  71         return offset;
  72 }
  73
  74 static int qd_alloc(struct gfs2_sbd *sdp, int user, uint32_t id,
  75                     struct gfs2_quota_data **qdp)
  76 {
  77         struct gfs2_quota_data *qd;
  78         int error;
  79
  80         qd = kzalloc(sizeof(struct gfs2_quota_data), GFP_KERNEL);
  81         if (!qd)
  82                 return -ENOMEM;
  83
  84         qd->qd_count = 1;
  85         qd->qd_id = id;
  86         if (user)
  87                 set_bit(QDF_USER, &qd->qd_flags);
  88         qd->qd_slot = -1;
  89
  90         error = gfs2_glock_get(sdp, 2 * (uint64_t)id + !user,
  91                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
  92         if (error)
  93                 goto fail;
  94
  95         error = gfs2_lvb_hold(qd->qd_gl);
  96         gfs2_glock_put(qd->qd_gl);
  97         if (error)
  98                 goto fail;
  99
 100         *qdp = qd;
 101
 102         return 0;
 103
 104  fail:
 105         kfree(qd);
 106         return error;
 107 }
 108
 109 static int qd_get(struct gfs2_sbd *sdp, int user, uint32_t id, int create,
 110                   struct gfs2_quota_data **qdp)
 111 {
 112         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
 113         int error, found;
 114
 115         *qdp = NULL;
 116
 117         for (;;) {
 118                 found = 0;
 119                 spin_lock(&sdp->sd_quota_spin);
 120                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 121                         if (qd->qd_id == id &&
 122                             !test_bit(QDF_USER, &qd->qd_flags) == !user) {
 123                                 qd->qd_count++;
 124                                 found = 1;
 125                                 break;
 126                         }
 127                 }
 128
 129                 if (!found)
 130                         qd = NULL;
 131
 132                 if (!qd && new_qd) {
 133                         qd = new_qd;
 134                         list_add(&qd->qd_list, &sdp->sd_quota_list);
 135                         atomic_inc(&sdp->sd_quota_count);
 136                         new_qd = NULL;
 137                 }
 138
 139                 spin_unlock(&sdp->sd_quota_spin);
 140
 141                 if (qd || !create) {
 142                         if (new_qd) {
 143                                 gfs2_lvb_unhold(new_qd->qd_gl);
 144                                 kfree(new_qd);
 145                         }
 146                         *qdp = qd;
 147                         return 0;
 148                 }
 149
 150                 error = qd_alloc(sdp, user, id, &new_qd);
 151                 if (error)
 152                         return error;
 153         }
 154 }
 155
 156 static void qd_hold(struct gfs2_quota_data *qd)
 157 {
 158         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 159
 160         spin_lock(&sdp->sd_quota_spin);
 161         gfs2_assert(sdp, qd->qd_count);
 162         qd->qd_count++;
 163         spin_unlock(&sdp->sd_quota_spin);
 164 }
 165
 166 static void qd_put(struct gfs2_quota_data *qd)
 167 {
 168         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 169         spin_lock(&sdp->sd_quota_spin);
 170         gfs2_assert(sdp, qd->qd_count);
 171         if (!--qd->qd_count)
 172                 qd->qd_last_touched = jiffies;
 173         spin_unlock(&sdp->sd_quota_spin);
 174 }
 175
 176 static int slot_get(struct gfs2_quota_data *qd)
 177 {
 178         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 179         unsigned int c, o = 0, b;
 180         unsigned char byte = 0;
 181
 182         spin_lock(&sdp->sd_quota_spin);
 183
 184         if (qd->qd_slot_count++) {
 185                 spin_unlock(&sdp->sd_quota_spin);
 186                 return 0;
 187         }
 188
 189         for (c = 0; c < sdp->sd_quota_chunks; c++)
 190                 for (o = 0; o < PAGE_SIZE; o++) {
 191                         byte = sdp->sd_quota_bitmap[c][o];
 192                         if (byte != 0xFF)
 193                                 goto found;
 194                 }
 195
 196         goto fail;
 197
 198  found:
 199         for (b = 0; b < 8; b++)
 200                 if (!(byte & (1 << b)))
 201                         break;
 202         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
 203
 204         if (qd->qd_slot >= sdp->sd_quota_slots)
 205                 goto fail;
 206
 207         sdp->sd_quota_bitmap[c][o] |= 1 << b;
 208
 209         spin_unlock(&sdp->sd_quota_spin);
 210
 211         return 0;
 212
 213  fail:
 214         qd->qd_slot_count--;
 215         spin_unlock(&sdp->sd_quota_spin);
 216         return -ENOSPC;
 217 }
 218
 219 static void slot_hold(struct gfs2_quota_data *qd)
 220 {
 221         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 222
 223         spin_lock(&sdp->sd_quota_spin);
 224         gfs2_assert(sdp, qd->qd_slot_count);
 225         qd->qd_slot_count++;
 226         spin_unlock(&sdp->sd_quota_spin);
 227 }
 228
 229 static void slot_put(struct gfs2_quota_data *qd)
 230 {
 231         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 232
 233         spin_lock(&sdp->sd_quota_spin);
 234         gfs2_assert(sdp, qd->qd_slot_count);
 235         if (!--qd->qd_slot_count) {
 236                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
 237                 qd->qd_slot = -1;
 238         }
 239         spin_unlock(&sdp->sd_quota_spin);
 240 }
 241
 242 static int bh_get(struct gfs2_quota_data *qd)
 243 {
 244         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 245         struct gfs2_inode *ip = get_v2ip(sdp->sd_qc_inode);
 246         unsigned int block, offset;
 247         uint64_t dblock;
 248         int new = 0;
 249         struct buffer_head *bh;
 250         int error;
 251
 252         down(&sdp->sd_quota_mutex);
 253
 254         if (qd->qd_bh_count++) {
 255                 up(&sdp->sd_quota_mutex);
 256                 return 0;
 257         }
 258
 259         block = qd->qd_slot / sdp->sd_qc_per_block;
 260         offset = qd->qd_slot % sdp->sd_qc_per_block;;
 261
 262         error = gfs2_block_map(ip, block, &new, &dblock, NULL);
 263         if (error)
 264                 goto fail;
 265         error = gfs2_meta_read(ip->i_gl, dblock, DIO_START | DIO_WAIT, &bh);
 266         if (error)
 267                 goto fail;
 268         error = -EIO;
 269         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
 270                 goto fail_brelse;
 271
 272         qd->qd_bh = bh;
 273         qd->qd_bh_qc = (struct gfs2_quota_change *)
 274                 (bh->b_data + sizeof(struct gfs2_meta_header) +
 275                  offset * sizeof(struct gfs2_quota_change));
 276
 277         up(&sdp->sd_quota_mutex);
 278
 279         return 0;
 280
 281  fail_brelse:
 282         brelse(bh);
 283
 284  fail:
 285         qd->qd_bh_count--;
 286         up(&sdp->sd_quota_mutex);
 287         return error;
 288 }
 289
 290 static void bh_put(struct gfs2_quota_data *qd)
 291 {
 292         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 293
 294         down(&sdp->sd_quota_mutex);
 295         gfs2_assert(sdp, qd->qd_bh_count);
 296         if (!--qd->qd_bh_count) {
 297                 brelse(qd->qd_bh);
 298                 qd->qd_bh = NULL;
 299                 qd->qd_bh_qc = NULL;
 300         }
 301         up(&sdp->sd_quota_mutex);
 302 }
 303
 304 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
 305 {
 306         struct gfs2_quota_data *qd = NULL;
 307         int error;
 308         int found = 0;
 309
 310         *qdp = NULL;
 311
 312         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 313                 return 0;
 314
 315         spin_lock(&sdp->sd_quota_spin);
 316
 317         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 318                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 319                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
 320                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
 321                         continue;
 322
 323                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 324
 325                 set_bit(QDF_LOCKED, &qd->qd_flags);
 326                 gfs2_assert_warn(sdp, qd->qd_count);
 327                 qd->qd_count++;
 328                 qd->qd_change_sync = qd->qd_change;
 329                 gfs2_assert_warn(sdp, qd->qd_slot_count);
 330                 qd->qd_slot_count++;
 331                 found = 1;
 332
 333                 break;
 334         }
 335
 336         if (!found)
 337                 qd = NULL;
 338
 339         spin_unlock(&sdp->sd_quota_spin);
 340
 341         if (qd) {
 342                 gfs2_assert_warn(sdp, qd->qd_change_sync);
 343                 error = bh_get(qd);
 344                 if (error) {
 345                         clear_bit(QDF_LOCKED, &qd->qd_flags);
 346                         slot_put(qd);
 347                         qd_put(qd);
 348                         return error;
 349                 }
 350         }
 351
 352         *qdp = qd;
 353
 354         return 0;
 355 }
 356
 357 static int qd_trylock(struct gfs2_quota_data *qd)
 358 {
 359         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 360
 361         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 362                 return 0;
 363
 364         spin_lock(&sdp->sd_quota_spin);
 365
 366         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 367             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
 368                 spin_unlock(&sdp->sd_quota_spin);
 369                 return 0;
 370         }
 371
 372         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 373
 374         set_bit(QDF_LOCKED, &qd->qd_flags);
 375         gfs2_assert_warn(sdp, qd->qd_count);
 376         qd->qd_count++;
 377         qd->qd_change_sync = qd->qd_change;
 378         gfs2_assert_warn(sdp, qd->qd_slot_count);
 379         qd->qd_slot_count++;
 380
 381         spin_unlock(&sdp->sd_quota_spin);
 382
 383         gfs2_assert_warn(sdp, qd->qd_change_sync);
 384         if (bh_get(qd)) {
 385                 clear_bit(QDF_LOCKED, &qd->qd_flags);
 386                 slot_put(qd);
 387                 qd_put(qd);
 388                 return 0;
 389         }
 390
 391         return 1;
 392 }
 393
 394 static void qd_unlock(struct gfs2_quota_data *qd)
 395 {
 396         gfs2_assert_warn(qd->qd_gl->gl_sbd, test_bit(QDF_LOCKED, &qd->qd_flags));
 397         clear_bit(QDF_LOCKED, &qd->qd_flags);
 398         bh_put(qd);
 399         slot_put(qd);
 400         qd_put(qd);
 401 }
 402
 403 static int qdsb_get(struct gfs2_sbd *sdp, int user, uint32_t id, int create,
 404                     struct gfs2_quota_data **qdp)
 405 {
 406         int error;
 407
 408         error = qd_get(sdp, user, id, create, qdp);
 409         if (error)
 410                 return error;
 411
 412         error = slot_get(*qdp);
 413         if (error)
 414                 goto fail;
 415
 416         error = bh_get(*qdp);
 417         if (error)
 418                 goto fail_slot;
 419
 420         return 0;
 421
 422  fail_slot:
 423         slot_put(*qdp);
 424
 425  fail:
 426         qd_put(*qdp);
 427         return error;
 428 }
 429
 430 static void qdsb_put(struct gfs2_quota_data *qd)
 431 {
 432         bh_put(qd);
 433         slot_put(qd);
 434         qd_put(qd);
 435 }
 436
 437 int gfs2_quota_hold(struct gfs2_inode *ip, uint32_t uid, uint32_t gid)
 438 {
 439         struct gfs2_sbd *sdp = ip->i_sbd;
 440         struct gfs2_alloc *al = &ip->i_alloc;
 441         struct gfs2_quota_data **qd = al->al_qd;
 442         int error;
 443
 444         if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
 445             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
 446                 return -EIO;
 447
 448         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 449                 return 0;
 450
 451         error = qdsb_get(sdp, QUOTA_USER, ip->i_di.di_uid, CREATE, qd);
 452         if (error)
 453                 goto out;
 454         al->al_qd_num++;
 455         qd++;
 456
 457         error = qdsb_get(sdp, QUOTA_GROUP, ip->i_di.di_gid, CREATE, qd);
 458         if (error)
 459                 goto out;
 460         al->al_qd_num++;
 461         qd++;
 462
 463         if (uid != NO_QUOTA_CHANGE && uid != ip->i_di.di_uid) {
 464                 error = qdsb_get(sdp, QUOTA_USER, uid, CREATE, qd);
 465                 if (error)
 466                         goto out;
 467                 al->al_qd_num++;
 468                 qd++;
 469         }
 470
 471         if (gid != NO_QUOTA_CHANGE && gid != ip->i_di.di_gid) {
 472                 error = qdsb_get(sdp, QUOTA_GROUP, gid, CREATE, qd);
 473                 if (error)
 474                         goto out;
 475                 al->al_qd_num++;
 476                 qd++;
 477         }
 478
 479  out:
 480         if (error)
 481                 gfs2_quota_unhold(ip);
 482
 483         return error;
 484 }
 485
 486 void gfs2_quota_unhold(struct gfs2_inode *ip)
 487 {
 488         struct gfs2_sbd *sdp = ip->i_sbd;
 489         struct gfs2_alloc *al = &ip->i_alloc;
 490         unsigned int x;
 491
 492         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 493
 494         for (x = 0; x < al->al_qd_num; x++) {
 495                 qdsb_put(al->al_qd[x]);
 496                 al->al_qd[x] = NULL;
 497         }
 498         al->al_qd_num = 0;
 499 }
 500
 501 static int sort_qd(const void *a, const void *b)
 502 {
 503         struct gfs2_quota_data *qd_a = *(struct gfs2_quota_data **)a;
 504         struct gfs2_quota_data *qd_b = *(struct gfs2_quota_data **)b;
 505         int ret = 0;
 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                         ret = -1;
 511                 else
 512                         ret = 1;
 513         } else {
 514                 if (qd_a->qd_id < qd_b->qd_id)
 515                         ret = -1;
 516                 else if (qd_a->qd_id > qd_b->qd_id)
 517                         ret = 1;
 518         }
 519
 520         return ret;
 521 }
 522
 523 static void do_qc(struct gfs2_quota_data *qd, int64_t change)
 524 {
 525         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 526         struct gfs2_inode *ip = get_v2ip(sdp->sd_qc_inode);
 527         struct gfs2_quota_change *qc = qd->qd_bh_qc;
 528         int64_t x;
 529
 530         down(&sdp->sd_quota_mutex);
 531         gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
 532
 533         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
 534                 qc->qc_change = 0;
 535                 qc->qc_flags = 0;
 536                 if (test_bit(QDF_USER, &qd->qd_flags))
 537                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
 538                 qc->qc_id = cpu_to_be32(qd->qd_id);
 539         }
 540
 541         x = qc->qc_change;
 542         x = be64_to_cpu(x) + 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         up(&sdp->sd_quota_mutex);
 562 }
 563
 564 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 565 {
 566         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
 567         struct gfs2_inode *ip = get_v2ip(sdp->sd_quota_inode);
 568         unsigned int data_blocks, ind_blocks;
 569         struct file_ra_state ra_state;
 570         struct gfs2_holder *ghs, i_gh;
 571         unsigned int qx, x;
 572         struct gfs2_quota_data *qd;
 573         loff_t offset;
 574         unsigned int nalloc = 0;
 575         struct gfs2_alloc *al = NULL;
 576         int error;
 577
 578         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 579                               &data_blocks, &ind_blocks);
 580
 581         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_KERNEL);
 582         if (!ghs)
 583                 return -ENOMEM;
 584
 585         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 586         for (qx = 0; qx < num_qd; qx++) {
 587                 error = gfs2_glock_nq_init(qda[qx]->qd_gl,
 588                                            LM_ST_EXCLUSIVE,
 589                                            GL_NOCACHE, &ghs[qx]);
 590                 if (error)
 591                         goto out;
 592         }
 593
 594         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 595         if (error)
 596                 goto out;
 597
 598         for (x = 0; x < num_qd; x++) {
 599                 int alloc_required;
 600
 601                 offset = qd2offset(qda[x]);
 602                 error = gfs2_write_alloc_required(ip, offset,
 603                                                   sizeof(struct gfs2_quota),
 604                                                   &alloc_required);
 605                 if (error)
 606                         goto out_gunlock;
 607                 if (alloc_required)
 608                         nalloc++;
 609         }
 610
 611         if (nalloc) {
 612                 al = gfs2_alloc_get(ip);
 613
 614                 al->al_requested = nalloc * (data_blocks + ind_blocks);
 615
 616                 error = gfs2_inplace_reserve(ip);
 617                 if (error)
 618                         goto out_alloc;
 619
 620                 error = gfs2_trans_begin(sdp,
 621                                          al->al_rgd->rd_ri.ri_length +
 622                                          num_qd * data_blocks +
 623                                          nalloc * ind_blocks +
 624                                          RES_DINODE + num_qd +
 625                                          RES_STATFS, 0);
 626                 if (error)
 627                         goto out_ipres;
 628         } else {
 629                 error = gfs2_trans_begin(sdp,
 630                                          num_qd * data_blocks +
 631                                          RES_DINODE + num_qd, 0);
 632                 if (error)
 633                         goto out_gunlock;
 634         }
 635
 636         file_ra_state_init(&ra_state, ip->i_vnode->i_mapping);
 637         for (x = 0; x < num_qd; x++) {
 638                 char buf[sizeof(struct gfs2_quota)];
 639                 struct gfs2_quota q;
 640
 641                 qd = qda[x];
 642                 offset = qd2offset(qd);
 643
 644                 /* The quota file may not be a multiple of
 645                    sizeof(struct gfs2_quota) bytes. */
 646                 memset(buf, 0, sizeof(struct gfs2_quota));
 647
 648                 error = gfs2_internal_read(ip, &ra_state, buf, &offset,
 649                                             sizeof(struct gfs2_quota));
 650                 if (error < 0)
 651                         goto out_end_trans;
 652
 653                 gfs2_quota_in(&q, buf);
 654                 q.qu_value += qda[x]->qd_change_sync;
 655                 gfs2_quota_out(&q, buf);
 656
 657                 error = gfs2_jdata_write_mem(ip, buf, offset,
 658                                              sizeof(struct gfs2_quota));
 659                 if (error < 0)
 660                         goto out_end_trans;
 661                 else if (error != sizeof(struct gfs2_quota)) {
 662                         error = -EIO;
 663                         goto out_end_trans;
 664                 }
 665
 666                 do_qc(qd, -qd->qd_change_sync);
 667
 668                 memset(&qd->qd_qb, 0, sizeof(struct gfs2_quota_lvb));
 669                 qd->qd_qb.qb_magic = GFS2_MAGIC;
 670                 qd->qd_qb.qb_limit = q.qu_limit;
 671                 qd->qd_qb.qb_warn = q.qu_warn;
 672                 qd->qd_qb.qb_value = q.qu_value;
 673
 674                 gfs2_quota_lvb_out(&qd->qd_qb, qd->qd_gl->gl_lvb);
 675         }
 676
 677         error = 0;
 678
 679  out_end_trans:
 680         gfs2_trans_end(sdp);
 681
 682  out_ipres:
 683         if (nalloc)
 684                 gfs2_inplace_release(ip);
 685
 686  out_alloc:
 687         if (nalloc)
 688                 gfs2_alloc_put(ip);
 689
 690  out_gunlock:
 691         gfs2_glock_dq_uninit(&i_gh);
 692
 693  out:
 694         while (qx--)
 695                 gfs2_glock_dq_uninit(&ghs[qx]);
 696         kfree(ghs);
 697         gfs2_log_flush_glock(ip->i_gl);
 698
 699         return error;
 700 }
 701
 702 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 703                     struct gfs2_holder *q_gh)
 704 {
 705         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 706         struct gfs2_holder i_gh;
 707         struct gfs2_quota q;
 708         char buf[sizeof(struct gfs2_quota)];
 709         struct file_ra_state ra_state;
 710         int error;
 711
 712         file_ra_state_init(&ra_state, sdp->sd_quota_inode->i_mapping);
 713  restart:
 714         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 715         if (error)
 716                 return error;
 717
 718         gfs2_quota_lvb_in(&qd->qd_qb, qd->qd_gl->gl_lvb);
 719
 720         if (force_refresh || qd->qd_qb.qb_magic != GFS2_MAGIC) {
 721                 loff_t pos;
 722                 gfs2_glock_dq_uninit(q_gh);
 723                 error = gfs2_glock_nq_init(qd->qd_gl,
 724                                           LM_ST_EXCLUSIVE, GL_NOCACHE,
 725                                           q_gh);
 726                 if (error)
 727                         return error;
 728
 729                 error = gfs2_glock_nq_init(get_v2ip(sdp->sd_quota_inode)->i_gl,
 730                                           LM_ST_SHARED, 0,
 731                                           &i_gh);
 732                 if (error)
 733                         goto fail;
 734
 735                 memset(buf, 0, sizeof(struct gfs2_quota));
 736                 pos = qd2offset(qd);
 737                 error = gfs2_internal_read(get_v2ip(sdp->sd_quota_inode),
 738                                             &ra_state, buf,
 739                                             &pos,
 740                                             sizeof(struct gfs2_quota));
 741                 if (error < 0)
 742                         goto fail_gunlock;
 743
 744                 gfs2_glock_dq_uninit(&i_gh);
 745
 746                 gfs2_quota_in(&q, buf);
 747
 748                 memset(&qd->qd_qb, 0, sizeof(struct gfs2_quota_lvb));
 749                 qd->qd_qb.qb_magic = GFS2_MAGIC;
 750                 qd->qd_qb.qb_limit = q.qu_limit;
 751                 qd->qd_qb.qb_warn = q.qu_warn;
 752                 qd->qd_qb.qb_value = q.qu_value;
 753
 754                 gfs2_quota_lvb_out(&qd->qd_qb, qd->qd_gl->gl_lvb);
 755
 756                 if (gfs2_glock_is_blocking(qd->qd_gl)) {
 757                         gfs2_glock_dq_uninit(q_gh);
 758                         force_refresh = 0;
 759                         goto restart;
 760                 }
 761         }
 762
 763         return 0;
 764
 765  fail_gunlock:
 766         gfs2_glock_dq_uninit(&i_gh);
 767
 768  fail:
 769         gfs2_glock_dq_uninit(q_gh);
 770
 771         return error;
 772 }
 773
 774 int gfs2_quota_lock(struct gfs2_inode *ip, uint32_t uid, uint32_t gid)
 775 {
 776         struct gfs2_sbd *sdp = ip->i_sbd;
 777         struct gfs2_alloc *al = &ip->i_alloc;
 778         unsigned int x;
 779         int error = 0;
 780
 781         gfs2_quota_hold(ip, uid, gid);
 782
 783         if (capable(CAP_SYS_RESOURCE) ||
 784             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 785                 return 0;
 786
 787         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
 788              sort_qd, NULL);
 789
 790         for (x = 0; x < al->al_qd_num; x++) {
 791                 error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
 792                 if (error)
 793                         break;
 794         }
 795
 796         if (!error)
 797                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
 798         else {
 799                 while (x--)
 800                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 801                 gfs2_quota_unhold(ip);
 802         }
 803
 804         return error;
 805 }
 806
 807 static int need_sync(struct gfs2_quota_data *qd)
 808 {
 809         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 810         struct gfs2_tune *gt = &sdp->sd_tune;
 811         int64_t value;
 812         unsigned int num, den;
 813         int do_sync = 1;
 814
 815         if (!qd->qd_qb.qb_limit)
 816                 return 0;
 817
 818         spin_lock(&sdp->sd_quota_spin);
 819         value = qd->qd_change;
 820         spin_unlock(&sdp->sd_quota_spin);
 821
 822         spin_lock(&gt->gt_spin);
 823         num = gt->gt_quota_scale_num;
 824         den = gt->gt_quota_scale_den;
 825         spin_unlock(&gt->gt_spin);
 826
 827         if (value < 0)
 828                 do_sync = 0;
 829         else if (qd->qd_qb.qb_value >= (int64_t)qd->qd_qb.qb_limit)
 830                 do_sync = 0;
 831         else {
 832                 value *= gfs2_jindex_size(sdp) * num;
 833                 do_div(value, den);
 834                 value += qd->qd_qb.qb_value;
 835                 if (value < (int64_t)qd->qd_qb.qb_limit)
 836                         do_sync = 0;
 837         }
 838
 839         return do_sync;
 840 }
 841
 842 void gfs2_quota_unlock(struct gfs2_inode *ip)
 843 {
 844         struct gfs2_alloc *al = &ip->i_alloc;
 845         struct gfs2_quota_data *qda[4];
 846         unsigned int count = 0;
 847         unsigned int x;
 848
 849         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
 850                 goto out;
 851
 852         for (x = 0; x < al->al_qd_num; x++) {
 853                 struct gfs2_quota_data *qd;
 854                 int sync;
 855
 856                 qd = al->al_qd[x];
 857                 sync = need_sync(qd);
 858
 859                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
 860
 861                 if (sync && qd_trylock(qd))
 862                         qda[count++] = qd;
 863         }
 864
 865         if (count) {
 866                 do_sync(count, qda);
 867                 for (x = 0; x < count; x++)
 868                         qd_unlock(qda[x]);
 869         }
 870
 871  out:
 872         gfs2_quota_unhold(ip);
 873 }
 874
 875 #define MAX_LINE 256
 876
 877 static int print_message(struct gfs2_quota_data *qd, char *type)
 878 {
 879         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 880         char *line;
 881         int len;
 882
 883         line = kmalloc(MAX_LINE, GFP_KERNEL);
 884         if (!line)
 885                 return -ENOMEM;
 886
 887         len = snprintf(line, MAX_LINE-1, "GFS2: fsid=%s: quota %s for %s %u\r\n",
 888                        sdp->sd_fsname, type,
 889                        (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
 890                        qd->qd_id);
 891         line[MAX_LINE-1] = 0;
 892
 893         if (current->signal) { /* Is this test still required? */
 894                 tty_write_message(current->signal->tty, line);
 895         }
 896
 897         kfree(line);
 898
 899         return 0;
 900 }
 901
 902 int gfs2_quota_check(struct gfs2_inode *ip, uint32_t uid, uint32_t gid)
 903 {
 904         struct gfs2_sbd *sdp = ip->i_sbd;
 905         struct gfs2_alloc *al = &ip->i_alloc;
 906         struct gfs2_quota_data *qd;
 907         int64_t value;
 908         unsigned int x;
 909         int error = 0;
 910
 911         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
 912                 return 0;
 913
 914         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 915                 return 0;
 916
 917         for (x = 0; x < al->al_qd_num; x++) {
 918                 qd = al->al_qd[x];
 919
 920                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
 921                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
 922                         continue;
 923
 924                 value = qd->qd_qb.qb_value;
 925                 spin_lock(&sdp->sd_quota_spin);
 926                 value += qd->qd_change;
 927                 spin_unlock(&sdp->sd_quota_spin);
 928
 929                 if (qd->qd_qb.qb_limit && (int64_t)qd->qd_qb.qb_limit < value) {
 930                         print_message(qd, "exceeded");
 931                         error = -EDQUOT;
 932                         break;
 933                 } else if (qd->qd_qb.qb_warn &&
 934                            (int64_t)qd->qd_qb.qb_warn < value &&
 935                            time_after_eq(jiffies, qd->qd_last_warn +
 936                                          gfs2_tune_get(sdp, gt_quota_warn_period) * HZ)) {
 937                         error = print_message(qd, "warning");
 938                         qd->qd_last_warn = jiffies;
 939                 }
 940         }
 941
 942         return error;
 943 }
 944
 945 void gfs2_quota_change(struct gfs2_inode *ip, int64_t change,
 946                        uint32_t uid, uint32_t gid)
 947 {
 948         struct gfs2_alloc *al = &ip->i_alloc;
 949         struct gfs2_quota_data *qd;
 950         unsigned int x;
 951         unsigned int found = 0;
 952
 953         if (gfs2_assert_warn(ip->i_sbd, change))
 954                 return;
 955         if (ip->i_di.di_flags & GFS2_DIF_SYSTEM)
 956                 return;
 957
 958         for (x = 0; x < al->al_qd_num; x++) {
 959                 qd = al->al_qd[x];
 960
 961                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
 962                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
 963                         do_qc(qd, change);
 964                         found++;
 965                 }
 966         }
 967 }
 968
 969 int gfs2_quota_sync(struct gfs2_sbd *sdp)
 970 {
 971         struct gfs2_quota_data **qda;
 972         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
 973         unsigned int num_qd;
 974         unsigned int x;
 975         int error = 0;
 976
 977         sdp->sd_quota_sync_gen++;
 978
 979         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
 980         if (!qda)
 981                 return -ENOMEM;
 982
 983         do {
 984                 num_qd = 0;
 985
 986                 for (;;) {
 987                         error = qd_fish(sdp, qda + num_qd);
 988                         if (error || !qda[num_qd])
 989                                 break;
 990                         if (++num_qd == max_qd)
 991                                 break;
 992                 }
 993
 994                 if (num_qd) {
 995                         if (!error)
 996                                 error = do_sync(num_qd, qda);
 997                         if (!error)
 998                                 for (x = 0; x < num_qd; x++)
 999                                         qda[x]->qd_sync_gen =
1000                                                 sdp->sd_quota_sync_gen;
1001
1002                         for (x = 0; x < num_qd; x++)
1003                                 qd_unlock(qda[x]);
1004                 }
1005         } while (!error && num_qd == max_qd);
1006
1007         kfree(qda);
1008
1009         return error;
1010 }
1011
1012 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, uint32_t id)
1013 {
1014         struct gfs2_quota_data *qd;
1015         struct gfs2_holder q_gh;
1016         int error;
1017
1018         error = qd_get(sdp, user, id, CREATE, &qd);
1019         if (error)
1020                 return error;
1021
1022         error = do_glock(qd, FORCE, &q_gh);
1023         if (!error)
1024                 gfs2_glock_dq_uninit(&q_gh);
1025
1026         qd_put(qd);
1027
1028         return error;
1029 }
1030
1031 int gfs2_quota_read(struct gfs2_sbd *sdp, int user, uint32_t id,
1032                     struct gfs2_quota *q)
1033 {
1034         struct gfs2_quota_data *qd;
1035         struct gfs2_holder q_gh;
1036         int error;
1037
1038         if (((user) ? (id != current->fsuid) : (!in_group_p(id))) &&
1039             !capable(CAP_SYS_ADMIN))
1040                 return -EACCES;
1041
1042         error = qd_get(sdp, user, id, CREATE, &qd);
1043         if (error)
1044                 return error;
1045
1046         error = do_glock(qd, NO_FORCE, &q_gh);
1047         if (error)
1048                 goto out;
1049
1050         memset(q, 0, sizeof(struct gfs2_quota));
1051         q->qu_limit = qd->qd_qb.qb_limit;
1052         q->qu_warn = qd->qd_qb.qb_warn;
1053         q->qu_value = qd->qd_qb.qb_value;
1054
1055         spin_lock(&sdp->sd_quota_spin);
1056         q->qu_value += qd->qd_change;
1057         spin_unlock(&sdp->sd_quota_spin);
1058
1059         gfs2_glock_dq_uninit(&q_gh);
1060
1061  out:
1062         qd_put(qd);
1063
1064         return error;
1065 }
1066
1067 int gfs2_quota_init(struct gfs2_sbd *sdp)
1068 {
1069         struct gfs2_inode *ip = get_v2ip(sdp->sd_qc_inode);
1070         unsigned int blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
1071         unsigned int x, slot = 0;
1072         unsigned int found = 0;
1073         uint64_t dblock;
1074         uint32_t extlen = 0;
1075         int error;
1076
1077         if (!ip->i_di.di_size ||
1078             ip->i_di.di_size > (64 << 20) ||
1079             ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1)) {
1080                 gfs2_consist_inode(ip);
1081                 return -EIO;
1082         }
1083         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1084         sdp->sd_quota_chunks = DIV_RU(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1085
1086         error = -ENOMEM;
1087
1088         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1089                                        sizeof(unsigned char *), GFP_KERNEL);
1090         if (!sdp->sd_quota_bitmap)
1091                 return error;
1092
1093         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1094                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_KERNEL);
1095                 if (!sdp->sd_quota_bitmap[x])
1096                         goto fail;
1097         }
1098
1099         for (x = 0; x < blocks; x++) {
1100                 struct buffer_head *bh;
1101                 unsigned int y;
1102
1103                 if (!extlen) {
1104                         int new = 0;
1105                         error = gfs2_block_map(ip, x, &new, &dblock, &extlen);
1106                         if (error)
1107                                 goto fail;
1108                 }
1109                 gfs2_meta_ra(ip->i_gl,  dblock, extlen);
1110                 error = gfs2_meta_read(ip->i_gl, dblock, DIO_START | DIO_WAIT,
1111                                        &bh);
1112                 if (error)
1113                         goto fail;
1114                 error = -EIO;
1115                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1116                         brelse(bh);
1117                         goto fail;
1118                 }
1119
1120                 for (y = 0;
1121                      y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1122                      y++, slot++) {
1123                         struct gfs2_quota_change qc;
1124                         struct gfs2_quota_data *qd;
1125
1126                         gfs2_quota_change_in(&qc, bh->b_data +
1127                                           sizeof(struct gfs2_meta_header) +
1128                                           y * sizeof(struct gfs2_quota_change));
1129                         if (!qc.qc_change)
1130                                 continue;
1131
1132                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1133                                          qc.qc_id, &qd);
1134                         if (error) {
1135                                 brelse(bh);
1136                                 goto fail;
1137                         }
1138
1139                         set_bit(QDF_CHANGE, &qd->qd_flags);
1140                         qd->qd_change = qc.qc_change;
1141                         qd->qd_slot = slot;
1142                         qd->qd_slot_count = 1;
1143                         qd->qd_last_touched = jiffies;
1144
1145                         spin_lock(&sdp->sd_quota_spin);
1146                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1147                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1148                         atomic_inc(&sdp->sd_quota_count);
1149                         spin_unlock(&sdp->sd_quota_spin);
1150
1151                         found++;
1152                 }
1153
1154                 brelse(bh);
1155                 dblock++;
1156                 extlen--;
1157         }
1158
1159         if (found)
1160                 fs_info(sdp, "found %u quota changes\n", found);
1161
1162         return 0;
1163
1164  fail:
1165         gfs2_quota_cleanup(sdp);
1166         return error;
1167 }
1168
1169 void gfs2_quota_scan(struct gfs2_sbd *sdp)
1170 {
1171         struct gfs2_quota_data *qd, *safe;
1172         LIST_HEAD(dead);
1173
1174         spin_lock(&sdp->sd_quota_spin);
1175         list_for_each_entry_safe(qd, safe, &sdp->sd_quota_list, qd_list) {
1176                 if (!qd->qd_count &&
1177                     time_after_eq(jiffies, qd->qd_last_touched +
1178                                 gfs2_tune_get(sdp, gt_quota_cache_secs) * HZ)) {
1179                         list_move(&qd->qd_list, &dead);
1180                         gfs2_assert_warn(sdp,
1181                                          atomic_read(&sdp->sd_quota_count) > 0);
1182                         atomic_dec(&sdp->sd_quota_count);
1183                 }
1184         }
1185         spin_unlock(&sdp->sd_quota_spin);
1186
1187         while (!list_empty(&dead)) {
1188                 qd = list_entry(dead.next, struct gfs2_quota_data, qd_list);
1189                 list_del(&qd->qd_list);
1190
1191                 gfs2_assert_warn(sdp, !qd->qd_change);
1192                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1193                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1194
1195                 gfs2_lvb_unhold(qd->qd_gl);
1196                 kfree(qd);
1197         }
1198 }
1199
1200 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1201 {
1202         struct list_head *head = &sdp->sd_quota_list;
1203         struct gfs2_quota_data *qd;
1204         unsigned int x;
1205
1206         spin_lock(&sdp->sd_quota_spin);
1207         while (!list_empty(head)) {
1208                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1209
1210                 if (qd->qd_count > 1 ||
1211                     (qd->qd_count && !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1212                         list_move(&qd->qd_list, head);
1213                         spin_unlock(&sdp->sd_quota_spin);
1214                         schedule();
1215                         spin_lock(&sdp->sd_quota_spin);
1216                         continue;
1217                 }
1218
1219                 list_del(&qd->qd_list);
1220                 atomic_dec(&sdp->sd_quota_count);
1221                 spin_unlock(&sdp->sd_quota_spin);
1222
1223                 if (!qd->qd_count) {
1224                         gfs2_assert_warn(sdp, !qd->qd_change);
1225                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1226                 } else
1227                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1228                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1229
1230                 gfs2_lvb_unhold(qd->qd_gl);
1231                 kfree(qd);
1232
1233                 spin_lock(&sdp->sd_quota_spin);
1234         }
1235         spin_unlock(&sdp->sd_quota_spin);
1236
1237         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1238
1239         if (sdp->sd_quota_bitmap) {
1240                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1241                         kfree(sdp->sd_quota_bitmap[x]);
1242                 kfree(sdp->sd_quota_bitmap);
1243         }
1244 }
1245