fs/gfs2/quota.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2007 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 for 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/mm.h>
  42 #include <linux/spinlock.h>
  43 #include <linux/completion.h>
  44 #include <linux/buffer_head.h>
  45 #include <linux/sort.h>
  46 #include <linux/fs.h>
  47 #include <linux/bio.h>
  48 #include <linux/gfs2_ondisk.h>
  49 #include <linux/kthread.h>
  50 #include <linux/freezer.h>
  51 #include <linux/quota.h>
  52 #include <linux/dqblk_xfs.h>
  53
  54 #include "gfs2.h"
  55 #include "incore.h"
  56 #include "bmap.h"
  57 #include "glock.h"
  58 #include "glops.h"
  59 #include "log.h"
  60 #include "meta_io.h"
  61 #include "quota.h"
  62 #include "rgrp.h"
  63 #include "super.h"
  64 #include "trans.h"
  65 #include "inode.h"
  66 #include "util.h"
  67
  68 struct gfs2_quota_change_host {
  69         u64 qc_change;
  70         u32 qc_flags; /* GFS2_QCF_... */
  71         struct kqid qc_id;
  72 };
  73
  74 static LIST_HEAD(qd_lru_list);
  75 static atomic_t qd_lru_count = ATOMIC_INIT(0);
  76 static DEFINE_SPINLOCK(qd_lru_lock);
  77
  78 unsigned long gfs2_qd_shrink_scan(struct shrinker *shrink,
  79                                   struct shrink_control *sc)
  80 {
  81         struct gfs2_quota_data *qd;
  82         struct gfs2_sbd *sdp;
  83         int nr_to_scan = sc->nr_to_scan;
  84         long freed = 0;
  85
  86         if (!(sc->gfp_mask & __GFP_FS))
  87                 return SHRINK_STOP;
  88
  89         spin_lock(&qd_lru_lock);
  90         while (nr_to_scan && !list_empty(&qd_lru_list)) {
  91                 qd = list_entry(qd_lru_list.next,
  92                                 struct gfs2_quota_data, qd_reclaim);
  93                 sdp = qd->qd_gl->gl_sbd;
  94
  95                 /* Free from the filesystem-specific list */
  96                 list_del(&qd->qd_list);
  97
  98                 gfs2_assert_warn(sdp, !qd->qd_change);
  99                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
 100                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
 101
 102                 gfs2_glock_put(qd->qd_gl);
 103                 atomic_dec(&sdp->sd_quota_count);
 104
 105                 /* Delete it from the common reclaim list */
 106                 list_del_init(&qd->qd_reclaim);
 107                 atomic_dec(&qd_lru_count);
 108                 spin_unlock(&qd_lru_lock);
 109                 kmem_cache_free(gfs2_quotad_cachep, qd);
 110                 spin_lock(&qd_lru_lock);
 111                 nr_to_scan--;
 112                 freed++;
 113         }
 114         spin_unlock(&qd_lru_lock);
 115         return freed;
 116 }
 117
 118 unsigned long gfs2_qd_shrink_count(struct shrinker *shrink,
 119                                    struct shrink_control *sc)
 120 {
 121         return vfs_pressure_ratio(atomic_read(&qd_lru_count));
 122 }
 123
 124 static u64 qd2index(struct gfs2_quota_data *qd)
 125 {
 126         struct kqid qid = qd->qd_id;
 127         return (2 * (u64)from_kqid(&init_user_ns, qid)) +
 128                 ((qid.type == USRQUOTA) ? 0 : 1);
 129 }
 130
 131 static u64 qd2offset(struct gfs2_quota_data *qd)
 132 {
 133         u64 offset;
 134
 135         offset = qd2index(qd);
 136         offset *= sizeof(struct gfs2_quota);
 137
 138         return offset;
 139 }
 140
 141 static int qd_alloc(struct gfs2_sbd *sdp, struct kqid qid,
 142                     struct gfs2_quota_data **qdp)
 143 {
 144         struct gfs2_quota_data *qd;
 145         int error;
 146
 147         qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
 148         if (!qd)
 149                 return -ENOMEM;
 150
 151         atomic_set(&qd->qd_count, 1);
 152         qd->qd_id = qid;
 153         qd->qd_slot = -1;
 154         INIT_LIST_HEAD(&qd->qd_reclaim);
 155
 156         error = gfs2_glock_get(sdp, qd2index(qd),
 157                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
 158         if (error)
 159                 goto fail;
 160
 161         *qdp = qd;
 162
 163         return 0;
 164
 165 fail:
 166         kmem_cache_free(gfs2_quotad_cachep, qd);
 167         return error;
 168 }
 169
 170 static int qd_get(struct gfs2_sbd *sdp, struct kqid qid,
 171                   struct gfs2_quota_data **qdp)
 172 {
 173         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
 174         int error, found;
 175
 176         *qdp = NULL;
 177
 178         for (;;) {
 179                 found = 0;
 180                 spin_lock(&qd_lru_lock);
 181                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 182                         if (qid_eq(qd->qd_id, qid)) {
 183                                 if (!atomic_read(&qd->qd_count) &&
 184                                     !list_empty(&qd->qd_reclaim)) {
 185                                         /* Remove it from reclaim list */
 186                                         list_del_init(&qd->qd_reclaim);
 187                                         atomic_dec(&qd_lru_count);
 188                                 }
 189                                 atomic_inc(&qd->qd_count);
 190                                 found = 1;
 191                                 break;
 192                         }
 193                 }
 194
 195                 if (!found)
 196                         qd = NULL;
 197
 198                 if (!qd && new_qd) {
 199                         qd = new_qd;
 200                         list_add(&qd->qd_list, &sdp->sd_quota_list);
 201                         atomic_inc(&sdp->sd_quota_count);
 202                         new_qd = NULL;
 203                 }
 204
 205                 spin_unlock(&qd_lru_lock);
 206
 207                 if (qd) {
 208                         if (new_qd) {
 209                                 gfs2_glock_put(new_qd->qd_gl);
 210                                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
 211                         }
 212                         *qdp = qd;
 213                         return 0;
 214                 }
 215
 216                 error = qd_alloc(sdp, qid, &new_qd);
 217                 if (error)
 218                         return error;
 219         }
 220 }
 221
 222 static void qd_hold(struct gfs2_quota_data *qd)
 223 {
 224         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 225         gfs2_assert(sdp, atomic_read(&qd->qd_count));
 226         atomic_inc(&qd->qd_count);
 227 }
 228
 229 static void qd_put(struct gfs2_quota_data *qd)
 230 {
 231         if (atomic_dec_and_lock(&qd->qd_count, &qd_lru_lock)) {
 232                 /* Add to the reclaim list */
 233                 list_add_tail(&qd->qd_reclaim, &qd_lru_list);
 234                 atomic_inc(&qd_lru_count);
 235                 spin_unlock(&qd_lru_lock);
 236         }
 237 }
 238
 239 static int slot_get(struct gfs2_quota_data *qd)
 240 {
 241         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 242         unsigned int c, o = 0, b;
 243         unsigned char byte = 0;
 244
 245         spin_lock(&qd_lru_lock);
 246
 247         if (qd->qd_slot_count++) {
 248                 spin_unlock(&qd_lru_lock);
 249                 return 0;
 250         }
 251
 252         for (c = 0; c < sdp->sd_quota_chunks; c++)
 253                 for (o = 0; o < PAGE_SIZE; o++) {
 254                         byte = sdp->sd_quota_bitmap[c][o];
 255                         if (byte != 0xFF)
 256                                 goto found;
 257                 }
 258
 259         goto fail;
 260
 261 found:
 262         for (b = 0; b < 8; b++)
 263                 if (!(byte & (1 << b)))
 264                         break;
 265         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
 266
 267         if (qd->qd_slot >= sdp->sd_quota_slots)
 268                 goto fail;
 269
 270         sdp->sd_quota_bitmap[c][o] |= 1 << b;
 271
 272         spin_unlock(&qd_lru_lock);
 273
 274         return 0;
 275
 276 fail:
 277         qd->qd_slot_count--;
 278         spin_unlock(&qd_lru_lock);
 279         return -ENOSPC;
 280 }
 281
 282 static void slot_hold(struct gfs2_quota_data *qd)
 283 {
 284         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 285
 286         spin_lock(&qd_lru_lock);
 287         gfs2_assert(sdp, qd->qd_slot_count);
 288         qd->qd_slot_count++;
 289         spin_unlock(&qd_lru_lock);
 290 }
 291
 292 static void slot_put(struct gfs2_quota_data *qd)
 293 {
 294         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 295
 296         spin_lock(&qd_lru_lock);
 297         gfs2_assert(sdp, qd->qd_slot_count);
 298         if (!--qd->qd_slot_count) {
 299                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
 300                 qd->qd_slot = -1;
 301         }
 302         spin_unlock(&qd_lru_lock);
 303 }
 304
 305 static int bh_get(struct gfs2_quota_data *qd)
 306 {
 307         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 308         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 309         unsigned int block, offset;
 310         struct buffer_head *bh;
 311         int error;
 312         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
 313
 314         mutex_lock(&sdp->sd_quota_mutex);
 315
 316         if (qd->qd_bh_count++) {
 317                 mutex_unlock(&sdp->sd_quota_mutex);
 318                 return 0;
 319         }
 320
 321         block = qd->qd_slot / sdp->sd_qc_per_block;
 322         offset = qd->qd_slot % sdp->sd_qc_per_block;
 323
 324         bh_map.b_size = 1 << ip->i_inode.i_blkbits;
 325         error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
 326         if (error)
 327                 goto fail;
 328         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
 329         if (error)
 330                 goto fail;
 331         error = -EIO;
 332         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
 333                 goto fail_brelse;
 334
 335         qd->qd_bh = bh;
 336         qd->qd_bh_qc = (struct gfs2_quota_change *)
 337                 (bh->b_data + sizeof(struct gfs2_meta_header) +
 338                  offset * sizeof(struct gfs2_quota_change));
 339
 340         mutex_unlock(&sdp->sd_quota_mutex);
 341
 342         return 0;
 343
 344 fail_brelse:
 345         brelse(bh);
 346 fail:
 347         qd->qd_bh_count--;
 348         mutex_unlock(&sdp->sd_quota_mutex);
 349         return error;
 350 }
 351
 352 static void bh_put(struct gfs2_quota_data *qd)
 353 {
 354         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 355
 356         mutex_lock(&sdp->sd_quota_mutex);
 357         gfs2_assert(sdp, qd->qd_bh_count);
 358         if (!--qd->qd_bh_count) {
 359                 brelse(qd->qd_bh);
 360                 qd->qd_bh = NULL;
 361                 qd->qd_bh_qc = NULL;
 362         }
 363         mutex_unlock(&sdp->sd_quota_mutex);
 364 }
 365
 366 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
 367 {
 368         struct gfs2_quota_data *qd = NULL;
 369         int error;
 370         int found = 0;
 371
 372         *qdp = NULL;
 373
 374         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 375                 return 0;
 376
 377         spin_lock(&qd_lru_lock);
 378
 379         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
 380                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 381                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
 382                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
 383                         continue;
 384
 385                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 386
 387                 set_bit(QDF_LOCKED, &qd->qd_flags);
 388                 gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
 389                 atomic_inc(&qd->qd_count);
 390                 qd->qd_change_sync = qd->qd_change;
 391                 gfs2_assert_warn(sdp, qd->qd_slot_count);
 392                 qd->qd_slot_count++;
 393                 found = 1;
 394
 395                 break;
 396         }
 397
 398         if (!found)
 399                 qd = NULL;
 400
 401         spin_unlock(&qd_lru_lock);
 402
 403         if (qd) {
 404                 gfs2_assert_warn(sdp, qd->qd_change_sync);
 405                 error = bh_get(qd);
 406                 if (error) {
 407                         clear_bit(QDF_LOCKED, &qd->qd_flags);
 408                         slot_put(qd);
 409                         qd_put(qd);
 410                         return error;
 411                 }
 412         }
 413
 414         *qdp = qd;
 415
 416         return 0;
 417 }
 418
 419 static int qd_trylock(struct gfs2_quota_data *qd)
 420 {
 421         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 422
 423         if (sdp->sd_vfs->s_flags & MS_RDONLY)
 424                 return 0;
 425
 426         spin_lock(&qd_lru_lock);
 427
 428         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
 429             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
 430                 spin_unlock(&qd_lru_lock);
 431                 return 0;
 432         }
 433
 434         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 435
 436         set_bit(QDF_LOCKED, &qd->qd_flags);
 437         gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
 438         atomic_inc(&qd->qd_count);
 439         qd->qd_change_sync = qd->qd_change;
 440         gfs2_assert_warn(sdp, qd->qd_slot_count);
 441         qd->qd_slot_count++;
 442
 443         spin_unlock(&qd_lru_lock);
 444
 445         gfs2_assert_warn(sdp, qd->qd_change_sync);
 446         if (bh_get(qd)) {
 447                 clear_bit(QDF_LOCKED, &qd->qd_flags);
 448                 slot_put(qd);
 449                 qd_put(qd);
 450                 return 0;
 451         }
 452
 453         return 1;
 454 }
 455
 456 static void qd_unlock(struct gfs2_quota_data *qd)
 457 {
 458         gfs2_assert_warn(qd->qd_gl->gl_sbd,
 459                          test_bit(QDF_LOCKED, &qd->qd_flags));
 460         clear_bit(QDF_LOCKED, &qd->qd_flags);
 461         bh_put(qd);
 462         slot_put(qd);
 463         qd_put(qd);
 464 }
 465
 466 static int qdsb_get(struct gfs2_sbd *sdp, struct kqid qid,
 467                     struct gfs2_quota_data **qdp)
 468 {
 469         int error;
 470
 471         error = qd_get(sdp, qid, qdp);
 472         if (error)
 473                 return error;
 474
 475         error = slot_get(*qdp);
 476         if (error)
 477                 goto fail;
 478
 479         error = bh_get(*qdp);
 480         if (error)
 481                 goto fail_slot;
 482
 483         return 0;
 484
 485 fail_slot:
 486         slot_put(*qdp);
 487 fail:
 488         qd_put(*qdp);
 489         return error;
 490 }
 491
 492 static void qdsb_put(struct gfs2_quota_data *qd)
 493 {
 494         bh_put(qd);
 495         slot_put(qd);
 496         qd_put(qd);
 497 }
 498
 499 int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
 500 {
 501         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 502         struct gfs2_quota_data **qd;
 503         int error;
 504
 505         if (ip->i_res == NULL) {
 506                 error = gfs2_rs_alloc(ip);
 507                 if (error)
 508                         return error;
 509         }
 510
 511         qd = ip->i_res->rs_qa_qd;
 512
 513         if (gfs2_assert_warn(sdp, !ip->i_res->rs_qa_qd_num) ||
 514             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
 515                 return -EIO;
 516
 517         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
 518                 return 0;
 519
 520         error = qdsb_get(sdp, make_kqid_uid(ip->i_inode.i_uid), qd);
 521         if (error)
 522                 goto out;
 523         ip->i_res->rs_qa_qd_num++;
 524         qd++;
 525
 526         error = qdsb_get(sdp, make_kqid_gid(ip->i_inode.i_gid), qd);
 527         if (error)
 528                 goto out;
 529         ip->i_res->rs_qa_qd_num++;
 530         qd++;
 531
 532         if (!uid_eq(uid, NO_UID_QUOTA_CHANGE) &&
 533             !uid_eq(uid, ip->i_inode.i_uid)) {
 534                 error = qdsb_get(sdp, make_kqid_uid(uid), qd);
 535                 if (error)
 536                         goto out;
 537                 ip->i_res->rs_qa_qd_num++;
 538                 qd++;
 539         }
 540
 541         if (!gid_eq(gid, NO_GID_QUOTA_CHANGE) &&
 542             !gid_eq(gid, ip->i_inode.i_gid)) {
 543                 error = qdsb_get(sdp, make_kqid_gid(gid), qd);
 544                 if (error)
 545                         goto out;
 546                 ip->i_res->rs_qa_qd_num++;
 547                 qd++;
 548         }
 549
 550 out:
 551         if (error)
 552                 gfs2_quota_unhold(ip);
 553         return error;
 554 }
 555
 556 void gfs2_quota_unhold(struct gfs2_inode *ip)
 557 {
 558         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 559         unsigned int x;
 560
 561         if (ip->i_res == NULL)
 562                 return;
 563         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 564
 565         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
 566                 qdsb_put(ip->i_res->rs_qa_qd[x]);
 567                 ip->i_res->rs_qa_qd[x] = NULL;
 568         }
 569         ip->i_res->rs_qa_qd_num = 0;
 570 }
 571
 572 static int sort_qd(const void *a, const void *b)
 573 {
 574         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
 575         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
 576
 577         if (qid_lt(qd_a->qd_id, qd_b->qd_id))
 578                 return -1;
 579         if (qid_lt(qd_b->qd_id, qd_a->qd_id))
 580                 return 1;
 581         return 0;
 582 }
 583
 584 static void do_qc(struct gfs2_quota_data *qd, s64 change)
 585 {
 586         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 587         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
 588         struct gfs2_quota_change *qc = qd->qd_bh_qc;
 589         s64 x;
 590
 591         mutex_lock(&sdp->sd_quota_mutex);
 592         gfs2_trans_add_meta(ip->i_gl, qd->qd_bh);
 593
 594         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
 595                 qc->qc_change = 0;
 596                 qc->qc_flags = 0;
 597                 if (qd->qd_id.type == USRQUOTA)
 598                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
 599                 qc->qc_id = cpu_to_be32(from_kqid(&init_user_ns, qd->qd_id));
 600         }
 601
 602         x = be64_to_cpu(qc->qc_change) + change;
 603         qc->qc_change = cpu_to_be64(x);
 604
 605         spin_lock(&qd_lru_lock);
 606         qd->qd_change = x;
 607         spin_unlock(&qd_lru_lock);
 608
 609         if (!x) {
 610                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
 611                 clear_bit(QDF_CHANGE, &qd->qd_flags);
 612                 qc->qc_flags = 0;
 613                 qc->qc_id = 0;
 614                 slot_put(qd);
 615                 qd_put(qd);
 616         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
 617                 qd_hold(qd);
 618                 slot_hold(qd);
 619         }
 620
 621         mutex_unlock(&sdp->sd_quota_mutex);
 622 }
 623
 624 /**
 625  * gfs2_adjust_quota - adjust record of current block usage
 626  * @ip: The quota inode
 627  * @loc: Offset of the entry in the quota file
 628  * @change: The amount of usage change to record
 629  * @qd: The quota data
 630  * @fdq: The updated limits to record
 631  *
 632  * This function was mostly borrowed from gfs2_block_truncate_page which was
 633  * in turn mostly borrowed from ext3
 634  *
 635  * Returns: 0 or -ve on error
 636  */
 637
 638 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 639                              s64 change, struct gfs2_quota_data *qd,
 640                              struct fs_disk_quota *fdq)
 641 {
 642         struct inode *inode = &ip->i_inode;
 643         struct gfs2_sbd *sdp = GFS2_SB(inode);
 644         struct address_space *mapping = inode->i_mapping;
 645         unsigned long index = loc >> PAGE_CACHE_SHIFT;
 646         unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
 647         unsigned blocksize, iblock, pos;
 648         struct buffer_head *bh;
 649         struct page *page;
 650         void *kaddr, *ptr;
 651         struct gfs2_quota q, *qp;
 652         int err, nbytes;
 653         u64 size;
 654
 655         if (gfs2_is_stuffed(ip)) {
 656                 err = gfs2_unstuff_dinode(ip, NULL);
 657                 if (err)
 658                         return err;
 659         }
 660
 661         memset(&q, 0, sizeof(struct gfs2_quota));
 662         err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
 663         if (err < 0)
 664                 return err;
 665
 666         err = -EIO;
 667         qp = &q;
 668         qp->qu_value = be64_to_cpu(qp->qu_value);
 669         qp->qu_value += change;
 670         qp->qu_value = cpu_to_be64(qp->qu_value);
 671         qd->qd_qb.qb_value = qp->qu_value;
 672         if (fdq) {
 673                 if (fdq->d_fieldmask & FS_DQ_BSOFT) {
 674                         qp->qu_warn = cpu_to_be64(fdq->d_blk_softlimit >> sdp->sd_fsb2bb_shift);
 675                         qd->qd_qb.qb_warn = qp->qu_warn;
 676                 }
 677                 if (fdq->d_fieldmask & FS_DQ_BHARD) {
 678                         qp->qu_limit = cpu_to_be64(fdq->d_blk_hardlimit >> sdp->sd_fsb2bb_shift);
 679                         qd->qd_qb.qb_limit = qp->qu_limit;
 680                 }
 681                 if (fdq->d_fieldmask & FS_DQ_BCOUNT) {
 682                         qp->qu_value = cpu_to_be64(fdq->d_bcount >> sdp->sd_fsb2bb_shift);
 683                         qd->qd_qb.qb_value = qp->qu_value;
 684                 }
 685         }
 686
 687         /* Write the quota into the quota file on disk */
 688         ptr = qp;
 689         nbytes = sizeof(struct gfs2_quota);
 690 get_a_page:
 691         page = find_or_create_page(mapping, index, GFP_NOFS);
 692         if (!page)
 693                 return -ENOMEM;
 694
 695         blocksize = inode->i_sb->s_blocksize;
 696         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
 697
 698         if (!page_has_buffers(page))
 699                 create_empty_buffers(page, blocksize, 0);
 700
 701         bh = page_buffers(page);
 702         pos = blocksize;
 703         while (offset >= pos) {
 704                 bh = bh->b_this_page;
 705                 iblock++;
 706                 pos += blocksize;
 707         }
 708
 709         if (!buffer_mapped(bh)) {
 710                 gfs2_block_map(inode, iblock, bh, 1);
 711                 if (!buffer_mapped(bh))
 712                         goto unlock_out;
 713                 /* If it's a newly allocated disk block for quota, zero it */
 714                 if (buffer_new(bh))
 715                         zero_user(page, pos - blocksize, bh->b_size);
 716         }
 717
 718         if (PageUptodate(page))
 719                 set_buffer_uptodate(bh);
 720
 721         if (!buffer_uptodate(bh)) {
 722                 ll_rw_block(READ | REQ_META, 1, &bh);
 723                 wait_on_buffer(bh);
 724                 if (!buffer_uptodate(bh))
 725                         goto unlock_out;
 726         }
 727
 728         gfs2_trans_add_data(ip->i_gl, bh);
 729
 730         kaddr = kmap_atomic(page);
 731         if (offset + sizeof(struct gfs2_quota) > PAGE_CACHE_SIZE)
 732                 nbytes = PAGE_CACHE_SIZE - offset;
 733         memcpy(kaddr + offset, ptr, nbytes);
 734         flush_dcache_page(page);
 735         kunmap_atomic(kaddr);
 736         unlock_page(page);
 737         page_cache_release(page);
 738
 739         /* If quota straddles page boundary, we need to update the rest of the
 740          * quota at the beginning of the next page */
 741         if ((offset + sizeof(struct gfs2_quota)) > PAGE_CACHE_SIZE) {
 742                 ptr = ptr + nbytes;
 743                 nbytes = sizeof(struct gfs2_quota) - nbytes;
 744                 offset = 0;
 745                 index++;
 746                 goto get_a_page;
 747         }
 748
 749         size = loc + sizeof(struct gfs2_quota);
 750         if (size > inode->i_size)
 751                 i_size_write(inode, size);
 752         inode->i_mtime = inode->i_atime = CURRENT_TIME;
 753         mark_inode_dirty(inode);
 754         return 0;
 755
 756 unlock_out:
 757         unlock_page(page);
 758         page_cache_release(page);
 759         return err;
 760 }
 761
 762 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 763 {
 764         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
 765         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 766         unsigned int data_blocks, ind_blocks;
 767         struct gfs2_holder *ghs, i_gh;
 768         unsigned int qx, x;
 769         struct gfs2_quota_data *qd;
 770         unsigned reserved;
 771         loff_t offset;
 772         unsigned int nalloc = 0, blocks;
 773         int error;
 774
 775         error = gfs2_rs_alloc(ip);
 776         if (error)
 777                 return error;
 778
 779         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 780                               &data_blocks, &ind_blocks);
 781
 782         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
 783         if (!ghs)
 784                 return -ENOMEM;
 785
 786         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 787         mutex_lock(&ip->i_inode.i_mutex);
 788         for (qx = 0; qx < num_qd; qx++) {
 789                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
 790                                            GL_NOCACHE, &ghs[qx]);
 791                 if (error)
 792                         goto out;
 793         }
 794
 795         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 796         if (error)
 797                 goto out;
 798
 799         for (x = 0; x < num_qd; x++) {
 800                 offset = qd2offset(qda[x]);
 801                 if (gfs2_write_alloc_required(ip, offset,
 802                                               sizeof(struct gfs2_quota)))
 803                         nalloc++;
 804         }
 805
 806         /*
 807          * 1 blk for unstuffing inode if stuffed. We add this extra
 808          * block to the reservation unconditionally. If the inode
 809          * doesn't need unstuffing, the block will be released to the
 810          * rgrp since it won't be allocated during the transaction
 811          */
 812         /* +3 in the end for unstuffing block, inode size update block
 813          * and another block in case quota straddles page boundary and
 814          * two blocks need to be updated instead of 1 */
 815         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
 816
 817         reserved = 1 + (nalloc * (data_blocks + ind_blocks));
 818         error = gfs2_inplace_reserve(ip, reserved, 0);
 819         if (error)
 820                 goto out_alloc;
 821
 822         if (nalloc)
 823                 blocks += gfs2_rg_blocks(ip, reserved) + nalloc * ind_blocks + RES_STATFS;
 824
 825         error = gfs2_trans_begin(sdp, blocks, 0);
 826         if (error)
 827                 goto out_ipres;
 828
 829         for (x = 0; x < num_qd; x++) {
 830                 qd = qda[x];
 831                 offset = qd2offset(qd);
 832                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
 833                 if (error)
 834                         goto out_end_trans;
 835
 836                 do_qc(qd, -qd->qd_change_sync);
 837                 set_bit(QDF_REFRESH, &qd->qd_flags);
 838         }
 839
 840         error = 0;
 841
 842 out_end_trans:
 843         gfs2_trans_end(sdp);
 844 out_ipres:
 845         gfs2_inplace_release(ip);
 846 out_alloc:
 847         gfs2_glock_dq_uninit(&i_gh);
 848 out:
 849         while (qx--)
 850                 gfs2_glock_dq_uninit(&ghs[qx]);
 851         mutex_unlock(&ip->i_inode.i_mutex);
 852         kfree(ghs);
 853         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
 854         return error;
 855 }
 856
 857 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
 858 {
 859         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 860         struct gfs2_quota q;
 861         struct gfs2_quota_lvb *qlvb;
 862         loff_t pos;
 863         int error;
 864
 865         memset(&q, 0, sizeof(struct gfs2_quota));
 866         pos = qd2offset(qd);
 867         error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
 868         if (error < 0)
 869                 return error;
 870
 871         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
 872         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
 873         qlvb->__pad = 0;
 874         qlvb->qb_limit = q.qu_limit;
 875         qlvb->qb_warn = q.qu_warn;
 876         qlvb->qb_value = q.qu_value;
 877         qd->qd_qb = *qlvb;
 878
 879         return 0;
 880 }
 881
 882 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
 883                     struct gfs2_holder *q_gh)
 884 {
 885         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 886         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
 887         struct gfs2_holder i_gh;
 888         int error;
 889
 890 restart:
 891         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
 892         if (error)
 893                 return error;
 894
 895         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
 896
 897         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
 898                 gfs2_glock_dq_uninit(q_gh);
 899                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
 900                                            GL_NOCACHE, q_gh);
 901                 if (error)
 902                         return error;
 903
 904                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
 905                 if (error)
 906                         goto fail;
 907
 908                 error = update_qd(sdp, qd);
 909                 if (error)
 910                         goto fail_gunlock;
 911
 912                 gfs2_glock_dq_uninit(&i_gh);
 913                 gfs2_glock_dq_uninit(q_gh);
 914                 force_refresh = 0;
 915                 goto restart;
 916         }
 917
 918         return 0;
 919
 920 fail_gunlock:
 921         gfs2_glock_dq_uninit(&i_gh);
 922 fail:
 923         gfs2_glock_dq_uninit(q_gh);
 924         return error;
 925 }
 926
 927 int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
 928 {
 929         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 930         struct gfs2_quota_data *qd;
 931         unsigned int x;
 932         int error = 0;
 933
 934         error = gfs2_quota_hold(ip, uid, gid);
 935         if (error)
 936                 return error;
 937
 938         if (capable(CAP_SYS_RESOURCE) ||
 939             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 940                 return 0;
 941
 942         sort(ip->i_res->rs_qa_qd, ip->i_res->rs_qa_qd_num,
 943              sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 944
 945         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
 946                 int force = NO_FORCE;
 947                 qd = ip->i_res->rs_qa_qd[x];
 948                 if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
 949                         force = FORCE;
 950                 error = do_glock(qd, force, &ip->i_res->rs_qa_qd_ghs[x]);
 951                 if (error)
 952                         break;
 953         }
 954
 955         if (!error)
 956                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
 957         else {
 958                 while (x--)
 959                         gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
 960                 gfs2_quota_unhold(ip);
 961         }
 962
 963         return error;
 964 }
 965
 966 static int need_sync(struct gfs2_quota_data *qd)
 967 {
 968         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
 969         struct gfs2_tune *gt = &sdp->sd_tune;
 970         s64 value;
 971         unsigned int num, den;
 972         int do_sync = 1;
 973
 974         if (!qd->qd_qb.qb_limit)
 975                 return 0;
 976
 977         spin_lock(&qd_lru_lock);
 978         value = qd->qd_change;
 979         spin_unlock(&qd_lru_lock);
 980
 981         spin_lock(&gt->gt_spin);
 982         num = gt->gt_quota_scale_num;
 983         den = gt->gt_quota_scale_den;
 984         spin_unlock(&gt->gt_spin);
 985
 986         if (value < 0)
 987                 do_sync = 0;
 988         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
 989                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 990                 do_sync = 0;
 991         else {
 992                 value *= gfs2_jindex_size(sdp) * num;
 993                 value = div_s64(value, den);
 994                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
 995                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 996                         do_sync = 0;
 997         }
 998
 999         return do_sync;
1000 }
1001
1002 void gfs2_quota_unlock(struct gfs2_inode *ip)
1003 {
1004         struct gfs2_quota_data *qda[4];
1005         unsigned int count = 0;
1006         unsigned int x;
1007
1008         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1009                 goto out;
1010
1011         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1012                 struct gfs2_quota_data *qd;
1013                 int sync;
1014
1015                 qd = ip->i_res->rs_qa_qd[x];
1016                 sync = need_sync(qd);
1017
1018                 gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
1019
1020                 if (sync && qd_trylock(qd))
1021                         qda[count++] = qd;
1022         }
1023
1024         if (count) {
1025                 do_sync(count, qda);
1026                 for (x = 0; x < count; x++)
1027                         qd_unlock(qda[x]);
1028         }
1029
1030 out:
1031         gfs2_quota_unhold(ip);
1032 }
1033
1034 #define MAX_LINE 256
1035
1036 static int print_message(struct gfs2_quota_data *qd, char *type)
1037 {
1038         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1039
1040         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\n",
1041                sdp->sd_fsname, type,
1042                (qd->qd_id.type == USRQUOTA) ? "user" : "group",
1043                from_kqid(&init_user_ns, qd->qd_id));
1044
1045         return 0;
1046 }
1047
1048 int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
1049 {
1050         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1051         struct gfs2_quota_data *qd;
1052         s64 value;
1053         unsigned int x;
1054         int error = 0;
1055
1056         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1057                 return 0;
1058
1059         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1060                 return 0;
1061
1062         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1063                 qd = ip->i_res->rs_qa_qd[x];
1064
1065                 if (!(qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1066                       qid_eq(qd->qd_id, make_kqid_gid(gid))))
1067                         continue;
1068
1069                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1070                 spin_lock(&qd_lru_lock);
1071                 value += qd->qd_change;
1072                 spin_unlock(&qd_lru_lock);
1073
1074                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
1075                         print_message(qd, "exceeded");
1076                         quota_send_warning(qd->qd_id,
1077                                            sdp->sd_vfs->s_dev, QUOTA_NL_BHARDWARN);
1078
1079                         error = -EDQUOT;
1080                         break;
1081                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
1082                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
1083                            time_after_eq(jiffies, qd->qd_last_warn +
1084                                          gfs2_tune_get(sdp,
1085                                                 gt_quota_warn_period) * HZ)) {
1086                         quota_send_warning(qd->qd_id,
1087                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1088                         error = print_message(qd, "warning");
1089                         qd->qd_last_warn = jiffies;
1090                 }
1091         }
1092
1093         return error;
1094 }
1095
1096 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1097                        kuid_t uid, kgid_t gid)
1098 {
1099         struct gfs2_quota_data *qd;
1100         unsigned int x;
1101
1102         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1103                 return;
1104         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1105                 return;
1106
1107         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1108                 qd = ip->i_res->rs_qa_qd[x];
1109
1110                 if (qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1111                     qid_eq(qd->qd_id, make_kqid_gid(gid))) {
1112                         do_qc(qd, change);
1113                 }
1114         }
1115 }
1116
1117 int gfs2_quota_sync(struct super_block *sb, int type)
1118 {
1119         struct gfs2_sbd *sdp = sb->s_fs_info;
1120         struct gfs2_quota_data **qda;
1121         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1122         unsigned int num_qd;
1123         unsigned int x;
1124         int error = 0;
1125
1126         sdp->sd_quota_sync_gen++;
1127
1128         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1129         if (!qda)
1130                 return -ENOMEM;
1131
1132         do {
1133                 num_qd = 0;
1134
1135                 for (;;) {
1136                         error = qd_fish(sdp, qda + num_qd);
1137                         if (error || !qda[num_qd])
1138                                 break;
1139                         if (++num_qd == max_qd)
1140                                 break;
1141                 }
1142
1143                 if (num_qd) {
1144                         if (!error)
1145                                 error = do_sync(num_qd, qda);
1146                         if (!error)
1147                                 for (x = 0; x < num_qd; x++)
1148                                         qda[x]->qd_sync_gen =
1149                                                 sdp->sd_quota_sync_gen;
1150
1151                         for (x = 0; x < num_qd; x++)
1152                                 qd_unlock(qda[x]);
1153                 }
1154         } while (!error && num_qd == max_qd);
1155
1156         kfree(qda);
1157
1158         return error;
1159 }
1160
1161 int gfs2_quota_refresh(struct gfs2_sbd *sdp, struct kqid qid)
1162 {
1163         struct gfs2_quota_data *qd;
1164         struct gfs2_holder q_gh;
1165         int error;
1166
1167         error = qd_get(sdp, qid, &qd);
1168         if (error)
1169                 return error;
1170
1171         error = do_glock(qd, FORCE, &q_gh);
1172         if (!error)
1173                 gfs2_glock_dq_uninit(&q_gh);
1174
1175         qd_put(qd);
1176         return error;
1177 }
1178
1179 static void gfs2_quota_change_in(struct gfs2_quota_change_host *qc, const void *buf)
1180 {
1181         const struct gfs2_quota_change *str = buf;
1182
1183         qc->qc_change = be64_to_cpu(str->qc_change);
1184         qc->qc_flags = be32_to_cpu(str->qc_flags);
1185         qc->qc_id = make_kqid(&init_user_ns,
1186                               (qc->qc_flags & GFS2_QCF_USER)?USRQUOTA:GRPQUOTA,
1187                               be32_to_cpu(str->qc_id));
1188 }
1189
1190 int gfs2_quota_init(struct gfs2_sbd *sdp)
1191 {
1192         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1193         u64 size = i_size_read(sdp->sd_qc_inode);
1194         unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1195         unsigned int x, slot = 0;
1196         unsigned int found = 0;
1197         u64 dblock;
1198         u32 extlen = 0;
1199         int error;
1200
1201         if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1202                 return -EIO;
1203
1204         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1205         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1206
1207         error = -ENOMEM;
1208
1209         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1210                                        sizeof(unsigned char *), GFP_NOFS);
1211         if (!sdp->sd_quota_bitmap)
1212                 return error;
1213
1214         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1215                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_NOFS);
1216                 if (!sdp->sd_quota_bitmap[x])
1217                         goto fail;
1218         }
1219
1220         for (x = 0; x < blocks; x++) {
1221                 struct buffer_head *bh;
1222                 unsigned int y;
1223
1224                 if (!extlen) {
1225                         int new = 0;
1226                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1227                         if (error)
1228                                 goto fail;
1229                 }
1230                 error = -EIO;
1231                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1232                 if (!bh)
1233                         goto fail;
1234                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1235                         brelse(bh);
1236                         goto fail;
1237                 }
1238
1239                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1240                      y++, slot++) {
1241                         struct gfs2_quota_change_host qc;
1242                         struct gfs2_quota_data *qd;
1243
1244                         gfs2_quota_change_in(&qc, bh->b_data +
1245                                           sizeof(struct gfs2_meta_header) +
1246                                           y * sizeof(struct gfs2_quota_change));
1247                         if (!qc.qc_change)
1248                                 continue;
1249
1250                         error = qd_alloc(sdp, qc.qc_id, &qd);
1251                         if (error) {
1252                                 brelse(bh);
1253                                 goto fail;
1254                         }
1255
1256                         set_bit(QDF_CHANGE, &qd->qd_flags);
1257                         qd->qd_change = qc.qc_change;
1258                         qd->qd_slot = slot;
1259                         qd->qd_slot_count = 1;
1260
1261                         spin_lock(&qd_lru_lock);
1262                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1263                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1264                         atomic_inc(&sdp->sd_quota_count);
1265                         spin_unlock(&qd_lru_lock);
1266
1267                         found++;
1268                 }
1269
1270                 brelse(bh);
1271                 dblock++;
1272                 extlen--;
1273         }
1274
1275         if (found)
1276                 fs_info(sdp, "found %u quota changes\n", found);
1277
1278         return 0;
1279
1280 fail:
1281         gfs2_quota_cleanup(sdp);
1282         return error;
1283 }
1284
1285 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1286 {
1287         struct list_head *head = &sdp->sd_quota_list;
1288         struct gfs2_quota_data *qd;
1289         unsigned int x;
1290
1291         spin_lock(&qd_lru_lock);
1292         while (!list_empty(head)) {
1293                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1294
1295                 if (atomic_read(&qd->qd_count) > 1 ||
1296                     (atomic_read(&qd->qd_count) &&
1297                      !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1298                         list_move(&qd->qd_list, head);
1299                         spin_unlock(&qd_lru_lock);
1300                         schedule();
1301                         spin_lock(&qd_lru_lock);
1302                         continue;
1303                 }
1304
1305                 list_del(&qd->qd_list);
1306                 /* Also remove if this qd exists in the reclaim list */
1307                 if (!list_empty(&qd->qd_reclaim)) {
1308                         list_del_init(&qd->qd_reclaim);
1309                         atomic_dec(&qd_lru_count);
1310                 }
1311                 atomic_dec(&sdp->sd_quota_count);
1312                 spin_unlock(&qd_lru_lock);
1313
1314                 if (!atomic_read(&qd->qd_count)) {
1315                         gfs2_assert_warn(sdp, !qd->qd_change);
1316                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1317                 } else
1318                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1319                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1320
1321                 gfs2_glock_put(qd->qd_gl);
1322                 kmem_cache_free(gfs2_quotad_cachep, qd);
1323
1324                 spin_lock(&qd_lru_lock);
1325         }
1326         spin_unlock(&qd_lru_lock);
1327
1328         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1329
1330         if (sdp->sd_quota_bitmap) {
1331                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1332                         kfree(sdp->sd_quota_bitmap[x]);
1333                 kfree(sdp->sd_quota_bitmap);
1334         }
1335 }
1336
1337 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1338 {
1339         if (error == 0 || error == -EROFS)
1340                 return;
1341         if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1342                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1343 }
1344
1345 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1346                                int (*fxn)(struct super_block *sb, int type),
1347                                unsigned long t, unsigned long *timeo,
1348                                unsigned int *new_timeo)
1349 {
1350         if (t >= *timeo) {
1351                 int error = fxn(sdp->sd_vfs, 0);
1352                 quotad_error(sdp, msg, error);
1353                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1354         } else {
1355                 *timeo -= t;
1356         }
1357 }
1358
1359 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1360 {
1361         struct gfs2_inode *ip;
1362
1363         while(1) {
1364                 ip = NULL;
1365                 spin_lock(&sdp->sd_trunc_lock);
1366                 if (!list_empty(&sdp->sd_trunc_list)) {
1367                         ip = list_entry(sdp->sd_trunc_list.next,
1368                                         struct gfs2_inode, i_trunc_list);
1369                         list_del_init(&ip->i_trunc_list);
1370                 }
1371                 spin_unlock(&sdp->sd_trunc_lock);
1372                 if (ip == NULL)
1373                         return;
1374                 gfs2_glock_finish_truncate(ip);
1375         }
1376 }
1377
1378 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1379         if (!sdp->sd_statfs_force_sync) {
1380                 sdp->sd_statfs_force_sync = 1;
1381                 wake_up(&sdp->sd_quota_wait);
1382         }
1383 }
1384
1385
1386 /**
1387  * gfs2_quotad - Write cached quota changes into the quota file
1388  * @sdp: Pointer to GFS2 superblock
1389  *
1390  */
1391
1392 int gfs2_quotad(void *data)
1393 {
1394         struct gfs2_sbd *sdp = data;
1395         struct gfs2_tune *tune = &sdp->sd_tune;
1396         unsigned long statfs_timeo = 0;
1397         unsigned long quotad_timeo = 0;
1398         unsigned long t = 0;
1399         DEFINE_WAIT(wait);
1400         int empty;
1401
1402         while (!kthread_should_stop()) {
1403
1404                 /* Update the master statfs file */
1405                 if (sdp->sd_statfs_force_sync) {
1406                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1407                         quotad_error(sdp, "statfs", error);
1408                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1409                 }
1410                 else
1411                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1412                                            &statfs_timeo,
1413                                            &tune->gt_statfs_quantum);
1414
1415                 /* Update quota file */
1416                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1417                                    &quotad_timeo, &tune->gt_quota_quantum);
1418
1419                 /* Check for & recover partially truncated inodes */
1420                 quotad_check_trunc_list(sdp);
1421
1422                 try_to_freeze();
1423
1424                 t = min(quotad_timeo, statfs_timeo);
1425
1426                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1427                 spin_lock(&sdp->sd_trunc_lock);
1428                 empty = list_empty(&sdp->sd_trunc_list);
1429                 spin_unlock(&sdp->sd_trunc_lock);
1430                 if (empty && !sdp->sd_statfs_force_sync)
1431                         t -= schedule_timeout(t);
1432                 else
1433                         t = 0;
1434                 finish_wait(&sdp->sd_quota_wait, &wait);
1435         }
1436
1437         return 0;
1438 }
1439
1440 static int gfs2_quota_get_xstate(struct super_block *sb,
1441                                  struct fs_quota_stat *fqs)
1442 {
1443         struct gfs2_sbd *sdp = sb->s_fs_info;
1444
1445         memset(fqs, 0, sizeof(struct fs_quota_stat));
1446         fqs->qs_version = FS_QSTAT_VERSION;
1447
1448         switch (sdp->sd_args.ar_quota) {
1449         case GFS2_QUOTA_ON:
1450                 fqs->qs_flags |= (FS_QUOTA_UDQ_ENFD | FS_QUOTA_GDQ_ENFD);
1451                 /*FALLTHRU*/
1452         case GFS2_QUOTA_ACCOUNT:
1453                 fqs->qs_flags |= (FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT);
1454                 break;
1455         case GFS2_QUOTA_OFF:
1456                 break;
1457         }
1458
1459         if (sdp->sd_quota_inode) {
1460                 fqs->qs_uquota.qfs_ino = GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1461                 fqs->qs_uquota.qfs_nblks = sdp->sd_quota_inode->i_blocks;
1462         }
1463         fqs->qs_uquota.qfs_nextents = 1; /* unsupported */
1464         fqs->qs_gquota = fqs->qs_uquota; /* its the same inode in both cases */
1465         fqs->qs_incoredqs = atomic_read(&qd_lru_count);
1466         return 0;
1467 }
1468
1469 static int gfs2_get_dqblk(struct super_block *sb, struct kqid qid,
1470                           struct fs_disk_quota *fdq)
1471 {
1472         struct gfs2_sbd *sdp = sb->s_fs_info;
1473         struct gfs2_quota_lvb *qlvb;
1474         struct gfs2_quota_data *qd;
1475         struct gfs2_holder q_gh;
1476         int error;
1477
1478         memset(fdq, 0, sizeof(struct fs_disk_quota));
1479
1480         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1481                 return -ESRCH; /* Crazy XFS error code */
1482
1483         if ((qid.type != USRQUOTA) &&
1484             (qid.type != GRPQUOTA))
1485                 return -EINVAL;
1486
1487         error = qd_get(sdp, qid, &qd);
1488         if (error)
1489                 return error;
1490         error = do_glock(qd, FORCE, &q_gh);
1491         if (error)
1492                 goto out;
1493
1494         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1495         fdq->d_version = FS_DQUOT_VERSION;
1496         fdq->d_flags = (qid.type == USRQUOTA) ? FS_USER_QUOTA : FS_GROUP_QUOTA;
1497         fdq->d_id = from_kqid_munged(current_user_ns(), qid);
1498         fdq->d_blk_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_fsb2bb_shift;
1499         fdq->d_blk_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_fsb2bb_shift;
1500         fdq->d_bcount = be64_to_cpu(qlvb->qb_value) << sdp->sd_fsb2bb_shift;
1501
1502         gfs2_glock_dq_uninit(&q_gh);
1503 out:
1504         qd_put(qd);
1505         return error;
1506 }
1507
1508 /* GFS2 only supports a subset of the XFS fields */
1509 #define GFS2_FIELDMASK (FS_DQ_BSOFT|FS_DQ_BHARD|FS_DQ_BCOUNT)
1510
1511 static int gfs2_set_dqblk(struct super_block *sb, struct kqid qid,
1512                           struct fs_disk_quota *fdq)
1513 {
1514         struct gfs2_sbd *sdp = sb->s_fs_info;
1515         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1516         struct gfs2_quota_data *qd;
1517         struct gfs2_holder q_gh, i_gh;
1518         unsigned int data_blocks, ind_blocks;
1519         unsigned int blocks = 0;
1520         int alloc_required;
1521         loff_t offset;
1522         int error;
1523
1524         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1525                 return -ESRCH; /* Crazy XFS error code */
1526
1527         if ((qid.type != USRQUOTA) &&
1528             (qid.type != GRPQUOTA))
1529                 return -EINVAL;
1530
1531         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1532                 return -EINVAL;
1533
1534         error = qd_get(sdp, qid, &qd);
1535         if (error)
1536                 return error;
1537
1538         error = gfs2_rs_alloc(ip);
1539         if (error)
1540                 goto out_put;
1541
1542         mutex_lock(&ip->i_inode.i_mutex);
1543         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1544         if (error)
1545                 goto out_unlockput;
1546         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1547         if (error)
1548                 goto out_q;
1549
1550         /* Check for existing entry, if none then alloc new blocks */
1551         error = update_qd(sdp, qd);
1552         if (error)
1553                 goto out_i;
1554
1555         /* If nothing has changed, this is a no-op */
1556         if ((fdq->d_fieldmask & FS_DQ_BSOFT) &&
1557             ((fdq->d_blk_softlimit >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1558                 fdq->d_fieldmask ^= FS_DQ_BSOFT;
1559
1560         if ((fdq->d_fieldmask & FS_DQ_BHARD) &&
1561             ((fdq->d_blk_hardlimit >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1562                 fdq->d_fieldmask ^= FS_DQ_BHARD;
1563
1564         if ((fdq->d_fieldmask & FS_DQ_BCOUNT) &&
1565             ((fdq->d_bcount >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1566                 fdq->d_fieldmask ^= FS_DQ_BCOUNT;
1567
1568         if (fdq->d_fieldmask == 0)
1569                 goto out_i;
1570
1571         offset = qd2offset(qd);
1572         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1573         if (gfs2_is_stuffed(ip))
1574                 alloc_required = 1;
1575         if (alloc_required) {
1576                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1577                                        &data_blocks, &ind_blocks);
1578                 blocks = 1 + data_blocks + ind_blocks;
1579                 error = gfs2_inplace_reserve(ip, blocks, 0);
1580                 if (error)
1581                         goto out_i;
1582                 blocks += gfs2_rg_blocks(ip, blocks);
1583         }
1584
1585         /* Some quotas span block boundaries and can update two blocks,
1586            adding an extra block to the transaction to handle such quotas */
1587         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1588         if (error)
1589                 goto out_release;
1590
1591         /* Apply changes */
1592         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1593
1594         gfs2_trans_end(sdp);
1595 out_release:
1596         if (alloc_required)
1597                 gfs2_inplace_release(ip);
1598 out_i:
1599         gfs2_glock_dq_uninit(&i_gh);
1600 out_q:
1601         gfs2_glock_dq_uninit(&q_gh);
1602 out_unlockput:
1603         mutex_unlock(&ip->i_inode.i_mutex);
1604 out_put:
1605         qd_put(qd);
1606         return error;
1607 }
1608
1609 const struct quotactl_ops gfs2_quotactl_ops = {
1610         .quota_sync     = gfs2_quota_sync,
1611         .get_xstate     = gfs2_quota_get_xstate,
1612         .get_dqblk      = gfs2_get_dqblk,
1613         .set_dqblk      = gfs2_set_dqblk,
1614 };