fs/dquot.c

   1 /*
   2  * Implementation of the diskquota system for the LINUX operating system. QUOTA
   3  * is implemented using the BSD system call interface as the means of
   4  * communication with the user level. This file contains the generic routines
   5  * called by the different filesystems on allocation of an inode or block.
   6  * These routines take care of the administration needed to have a consistent
   7  * diskquota tracking system. The ideas of both user and group quotas are based
   8  * on the Melbourne quota system as used on BSD derived systems. The internal
   9  * implementation is based on one of the several variants of the LINUX
  10  * inode-subsystem with added complexity of the diskquota system.
  11  *
  12  * Version: $Id: dquot.c,v 6.3 1996/11/17 18:35:34 mvw Exp mvw $
  13  *
  14  * Author:      Marco van Wieringen <mvw@planets.elm.net>
  15  *
  16  * Fixes:   Dmitry Gorodchanin <pgmdsg@ibi.com>, 11 Feb 96
  17  *
  18  *              Revised list management to avoid races
  19  *              -- Bill Hawes, <whawes@star.net>, 9/98
  20  *
  21  *              Fixed races in dquot_transfer(), dqget() and dquot_alloc_...().
  22  *              As the consequence the locking was moved from dquot_decr_...(),
  23  *              dquot_incr_...() to calling functions.
  24  *              invalidate_dquots() now writes modified dquots.
  25  *              Serialized quota_off() and quota_on() for mount point.
  26  *              Fixed a few bugs in grow_dquots().
  27  *              Fixed deadlock in write_dquot() - we no longer account quotas on
  28  *              quota files
  29  *              remove_dquot_ref() moved to inode.c - it now traverses through inodes
  30  *              add_dquot_ref() restarts after blocking
  31  *              Added check for bogus uid and fixed check for group in quotactl.
  32  *              Jan Kara, <jack@suse.cz>, sponsored by SuSE CR, 10-11/99
  33  *
  34  *              Used struct list_head instead of own list struct
  35  *              Invalidation of referenced dquots is no longer possible
  36  *              Improved free_dquots list management
  37  *              Quota and i_blocks are now updated in one place to avoid races
  38  *              Warnings are now delayed so we won't block in critical section
  39  *              Write updated not to require dquot lock
  40  *              Jan Kara, <jack@suse.cz>, 9/2000
  41  *
  42  *              Added dynamic quota structure allocation
  43  *              Jan Kara <jack@suse.cz> 12/2000
  44  *
  45  *              Rewritten quota interface. Implemented new quota format and
  46  *              formats registering.
  47  *              Jan Kara, <jack@suse.cz>, 2001,2002
  48  *
  49  *              New SMP locking.
  50  *              Jan Kara, <jack@suse.cz>, 10/2002
  51  *
  52  *              Added journalled quota support
  53  *              Jan Kara, <jack@suse.cz>, 2003,2004
  54  *
  55  * (C) Copyright 1994 - 1997 Marco van Wieringen
  56  */
  57
  58 #include <linux/errno.h>
  59 #include <linux/kernel.h>
  60 #include <linux/fs.h>
  61 #include <linux/mount.h>
  62 #include <linux/mm.h>
  63 #include <linux/time.h>
  64 #include <linux/types.h>
  65 #include <linux/string.h>
  66 #include <linux/fcntl.h>
  67 #include <linux/stat.h>
  68 #include <linux/tty.h>
  69 #include <linux/file.h>
  70 #include <linux/slab.h>
  71 #include <linux/sysctl.h>
  72 #include <linux/smp_lock.h>
  73 #include <linux/init.h>
  74 #include <linux/module.h>
  75 #include <linux/proc_fs.h>
  76 #include <linux/security.h>
  77 #include <linux/kmod.h>
  78
  79 #include <asm/uaccess.h>
  80
  81 #define __DQUOT_PARANOIA
  82
  83 /*
  84  * There are two quota SMP locks. dq_list_lock protects all lists with quotas
  85  * and quota formats and also dqstats structure containing statistics about the
  86  * lists. dq_data_lock protects data from dq_dqb and also mem_dqinfo structures
  87  * and also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes.
  88  * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly
  89  * in inode_add_bytes() and inode_sub_bytes().
  90  *
  91  * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock
  92  *
  93  * Note that some things (eg. sb pointer, type, id) doesn't change during
  94  * the life of the dquot structure and so needn't to be protected by a lock
  95  *
  96  * Any operation working on dquots via inode pointers must hold dqptr_sem.  If
  97  * operation is just reading pointers from inode (or not using them at all) the
  98  * read lock is enough. If pointers are altered function must hold write lock.
  99  * If operation is holding reference to dquot in other way (e.g. quotactl ops)
 100  * it must be guarded by dqonoff_sem.
 101  * This locking assures that:
 102  *   a) update/access to dquot pointers in inode is serialized
 103  *   b) everyone is guarded against invalidate_dquots()
 104  *
 105  * Each dquot has its dq_lock semaphore. Locked dquots might not be referenced
 106  * from inodes (dquot_alloc_space() and such don't check the dq_lock).
 107  * Currently dquot is locked only when it is being read to memory (or space for
 108  * it is being allocated) on the first dqget() and when it is being released on
 109  * the last dqput(). The allocation and release oparations are serialized by
 110  * the dq_lock and by checking the use count in dquot_release().  Write
 111  * operations on dquots don't hold dq_lock as they copy data under dq_data_lock
 112  * spinlock to internal buffers before writing.
 113  *
 114  * Lock ordering (including journal_lock) is following:
 115  *  dqonoff_sem > journal_lock > dqptr_sem > dquot->dq_lock > dqio_sem
 116  */
 117
 118 spinlock_t dq_list_lock = SPIN_LOCK_UNLOCKED;
 119 spinlock_t dq_data_lock = SPIN_LOCK_UNLOCKED;
 120
 121 static char *quotatypes[] = INITQFNAMES;
 122 static struct quota_format_type *quota_formats; /* List of registered formats */
 123 static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES;
 124
 125 int register_quota_format(struct quota_format_type *fmt)
 126 {
 127         spin_lock(&dq_list_lock);
 128         fmt->qf_next = quota_formats;
 129         quota_formats = fmt;
 130         spin_unlock(&dq_list_lock);
 131         return 0;
 132 }
 133
 134 void unregister_quota_format(struct quota_format_type *fmt)
 135 {
 136         struct quota_format_type **actqf;
 137
 138         spin_lock(&dq_list_lock);
 139         for (actqf = &quota_formats; *actqf && *actqf != fmt; actqf = &(*actqf)->qf_next);
 140         if (*actqf)
 141                 *actqf = (*actqf)->qf_next;
 142         spin_unlock(&dq_list_lock);
 143 }
 144
 145 static struct quota_format_type *find_quota_format(int id)
 146 {
 147         struct quota_format_type *actqf;
 148
 149         spin_lock(&dq_list_lock);
 150         for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; actqf = actqf->qf_next);
 151         if (!actqf || !try_module_get(actqf->qf_owner)) {
 152                 int qm;
 153
 154                 spin_unlock(&dq_list_lock);
 155
 156                 for (qm = 0; module_names[qm].qm_fmt_id && module_names[qm].qm_fmt_id != id; qm++);
 157                 if (!module_names[qm].qm_fmt_id || request_module(module_names[qm].qm_mod_name))
 158                         return NULL;
 159
 160                 spin_lock(&dq_list_lock);
 161                 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; actqf = actqf->qf_next);
 162                 if (actqf && !try_module_get(actqf->qf_owner))
 163                         actqf = NULL;
 164         }
 165         spin_unlock(&dq_list_lock);
 166         return actqf;
 167 }
 168
 169 static void put_quota_format(struct quota_format_type *fmt)
 170 {
 171         module_put(fmt->qf_owner);
 172 }
 173
 174 /*
 175  * Dquot List Management:
 176  * The quota code uses three lists for dquot management: the inuse_list,
 177  * free_dquots, and dquot_hash[] array. A single dquot structure may be
 178  * on all three lists, depending on its current state.
 179  *
 180  * All dquots are placed to the end of inuse_list when first created, and this
 181  * list is used for the sync and invalidate operations, which must look
 182  * at every dquot.
 183  *
 184  * Unused dquots (dq_count == 0) are added to the free_dquots list when freed,
 185  * and this list is searched whenever we need an available dquot.  Dquots are
 186  * removed from the list as soon as they are used again, and
 187  * dqstats.free_dquots gives the number of dquots on the list. When
 188  * dquot is invalidated it's completely released from memory.
 189  *
 190  * Dquots with a specific identity (device, type and id) are placed on
 191  * one of the dquot_hash[] hash chains. The provides an efficient search
 192  * mechanism to locate a specific dquot.
 193  */
 194
 195 static LIST_HEAD(inuse_list);
 196 static LIST_HEAD(free_dquots);
 197 unsigned int dq_hash_bits, dq_hash_mask;
 198 static struct hlist_head *dquot_hash;
 199
 200 struct dqstats dqstats;
 201
 202 static void dqput(struct dquot *dquot);
 203
 204 static inline int const hashfn(struct super_block *sb, unsigned int id, int type)
 205 {
 206         unsigned long tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type);
 207         return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask;
 208 }
 209
 210 /*
 211  * Following list functions expect dq_list_lock to be held
 212  */
 213 static inline void insert_dquot_hash(struct dquot *dquot)
 214 {
 215         struct hlist_head *head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id, dquot->dq_type);
 216         hlist_add_head(&dquot->dq_hash, head);
 217 }
 218
 219 static inline void remove_dquot_hash(struct dquot *dquot)
 220 {
 221         hlist_del_init(&dquot->dq_hash);
 222 }
 223
 224 static inline struct dquot *find_dquot(unsigned int hashent, struct super_block *sb, unsigned int id, int type)
 225 {
 226         struct hlist_node *node;
 227         struct dquot *dquot;
 228
 229         hlist_for_each (node, dquot_hash+hashent) {
 230                 dquot = hlist_entry(node, struct dquot, dq_hash);
 231                 if (dquot->dq_sb == sb && dquot->dq_id == id && dquot->dq_type == type)
 232                         return dquot;
 233         }
 234         return NODQUOT;
 235 }
 236
 237 /* Add a dquot to the tail of the free list */
 238 static inline void put_dquot_last(struct dquot *dquot)
 239 {
 240         list_add(&dquot->dq_free, free_dquots.prev);
 241         dqstats.free_dquots++;
 242 }
 243
 244 static inline void remove_free_dquot(struct dquot *dquot)
 245 {
 246         if (list_empty(&dquot->dq_free))
 247                 return;
 248         list_del_init(&dquot->dq_free);
 249         dqstats.free_dquots--;
 250 }
 251
 252 static inline void put_inuse(struct dquot *dquot)
 253 {
 254         /* We add to the back of inuse list so we don't have to restart
 255          * when traversing this list and we block */
 256         list_add(&dquot->dq_inuse, inuse_list.prev);
 257         dqstats.allocated_dquots++;
 258 }
 259
 260 static inline void remove_inuse(struct dquot *dquot)
 261 {
 262         dqstats.allocated_dquots--;
 263         list_del(&dquot->dq_inuse);
 264 }
 265 /*
 266  * End of list functions needing dq_list_lock
 267  */
 268
 269 static void wait_on_dquot(struct dquot *dquot)
 270 {
 271         down(&dquot->dq_lock);
 272         up(&dquot->dq_lock);
 273 }
 274
 275 #define mark_dquot_dirty(dquot) ((dquot)->dq_sb->dq_op->mark_dirty(dquot))
 276
 277 int dquot_mark_dquot_dirty(struct dquot *dquot)
 278 {
 279         spin_lock(&dq_list_lock);
 280         if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags))
 281                 list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)->
 282                                 info[dquot->dq_type].dqi_dirty_list);
 283         spin_unlock(&dq_list_lock);
 284         return 0;
 285 }
 286
 287 /* This function needs dq_list_lock */
 288 static inline int clear_dquot_dirty(struct dquot *dquot)
 289 {
 290         if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags))
 291                 return 0;
 292         list_del_init(&dquot->dq_dirty);
 293         return 1;
 294 }
 295
 296 void mark_info_dirty(struct super_block *sb, int type)
 297 {
 298         set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags);
 299 }
 300 EXPORT_SYMBOL(mark_info_dirty);
 301
 302 /*
 303  *      Read dquot from disk and alloc space for it
 304  */
 305
 306 int dquot_acquire(struct dquot *dquot)
 307 {
 308         int ret = 0;
 309         struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
 310
 311         down(&dquot->dq_lock);
 312         down(&dqopt->dqio_sem);
 313         if (!test_bit(DQ_READ_B, &dquot->dq_flags))
 314                 ret = dqopt->ops[dquot->dq_type]->read_dqblk(dquot);
 315         if (ret < 0)
 316                 goto out_iolock;
 317         set_bit(DQ_READ_B, &dquot->dq_flags);
 318         /* Instantiate dquot if needed */
 319         if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) {
 320                 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
 321                 if (ret < 0)
 322                         goto out_iolock;
 323         }
 324         set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
 325 out_iolock:
 326         up(&dqopt->dqio_sem);
 327         up(&dquot->dq_lock);
 328         return ret;
 329 }
 330
 331 /*
 332  *      Write dquot to disk
 333  */
 334 int dquot_commit(struct dquot *dquot)
 335 {
 336         int ret = 0;
 337         struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
 338
 339         down(&dqopt->dqio_sem);
 340         spin_lock(&dq_list_lock);
 341         if (!clear_dquot_dirty(dquot)) {
 342                 spin_unlock(&dq_list_lock);
 343                 goto out_sem;
 344         }
 345         spin_unlock(&dq_list_lock);
 346         /* Inactive dquot can be only if there was error during read/init
 347          * => we have better not writing it */
 348         if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
 349                 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
 350 out_sem:
 351         up(&dqopt->dqio_sem);
 352         if (info_dirty(&dqopt->info[dquot->dq_type]))
 353                 dquot->dq_sb->dq_op->write_info(dquot->dq_sb, dquot->dq_type);
 354         return ret;
 355 }
 356
 357 /*
 358  *      Release dquot
 359  */
 360 int dquot_release(struct dquot *dquot)
 361 {
 362         int ret = 0;
 363         struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
 364
 365         down(&dquot->dq_lock);
 366         /* Check whether we are not racing with some other dqget() */
 367         if (atomic_read(&dquot->dq_count) > 1)
 368                 goto out_dqlock;
 369         down(&dqopt->dqio_sem);
 370         ret = dqopt->ops[dquot->dq_type]->release_dqblk(dquot);
 371         clear_bit(DQ_ACTIVE_B, &dquot->dq_flags);
 372         up(&dqopt->dqio_sem);
 373 out_dqlock:
 374         up(&dquot->dq_lock);
 375         return ret;
 376 }
 377
 378 /* Invalidate all dquots on the list. Note that this function is called after
 379  * quota is disabled and pointers from inodes removed so there cannot be new
 380  * quota users. Also because we hold dqonoff_sem there can be no quota users
 381  * for this sb+type at all. */
 382 static void invalidate_dquots(struct super_block *sb, int type)
 383 {
 384         struct dquot *dquot;
 385         struct list_head *head;
 386
 387         spin_lock(&dq_list_lock);
 388         for (head = inuse_list.next; head != &inuse_list;) {
 389                 dquot = list_entry(head, struct dquot, dq_inuse);
 390                 head = head->next;
 391                 if (dquot->dq_sb != sb)
 392                         continue;
 393                 if (dquot->dq_type != type)
 394                         continue;
 395 #ifdef __DQUOT_PARANOIA
 396                 if (atomic_read(&dquot->dq_count))
 397                         BUG();
 398 #endif
 399                 /* Quota now has no users and it has been written on last dqput() */
 400                 remove_dquot_hash(dquot);
 401                 remove_free_dquot(dquot);
 402                 remove_inuse(dquot);
 403                 kmem_cache_free(dquot_cachep, dquot);
 404         }
 405         spin_unlock(&dq_list_lock);
 406 }
 407
 408 int vfs_quota_sync(struct super_block *sb, int type)
 409 {
 410         struct list_head *dirty;
 411         struct dquot *dquot;
 412         struct quota_info *dqopt = sb_dqopt(sb);
 413         int cnt;
 414
 415         down(&dqopt->dqonoff_sem);
 416         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
 417                 if (type != -1 && cnt != type)
 418                         continue;
 419                 if (!sb_has_quota_enabled(sb, cnt))
 420                         continue;
 421                 spin_lock(&dq_list_lock);
 422                 dirty = &dqopt->info[cnt].dqi_dirty_list;
 423                 while (!list_empty(dirty)) {
 424                         dquot = list_entry(dirty->next, struct dquot, dq_dirty);
 425                         /* Dirty and inactive can be only bad dquot... */
 426                         if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
 427                                 clear_dquot_dirty(dquot);
 428                                 continue;
 429                         }
 430                         /* Now we have active dquot from which someone is
 431                          * holding reference so we can safely just increase
 432                          * use count */
 433                         atomic_inc(&dquot->dq_count);
 434                         dqstats.lookups++;
 435                         spin_unlock(&dq_list_lock);
 436                         sb->dq_op->write_dquot(dquot);
 437                         dqput(dquot);
 438                         spin_lock(&dq_list_lock);
 439                 }
 440                 spin_unlock(&dq_list_lock);
 441         }
 442
 443         for (cnt = 0; cnt < MAXQUOTAS; cnt++)
 444                 if ((cnt == type || type == -1) && sb_has_quota_enabled(sb, cnt)
 445                         && info_dirty(&dqopt->info[cnt]))
 446                         sb->dq_op->write_info(sb, cnt);
 447         spin_lock(&dq_list_lock);
 448         dqstats.syncs++;
 449         spin_unlock(&dq_list_lock);
 450         up(&dqopt->dqonoff_sem);
 451
 452         return 0;
 453 }
 454
 455 /* Free unused dquots from cache */
 456 static void prune_dqcache(int count)
 457 {
 458         struct list_head *head;
 459         struct dquot *dquot;
 460
 461         head = free_dquots.prev;
 462         while (head != &free_dquots && count) {
 463                 dquot = list_entry(head, struct dquot, dq_free);
 464                 remove_dquot_hash(dquot);
 465                 remove_free_dquot(dquot);
 466                 remove_inuse(dquot);
 467                 kmem_cache_free(dquot_cachep, dquot);
 468                 count--;
 469                 head = free_dquots.prev;
 470         }
 471 }
 472
 473 /*
 474  * This is called from kswapd when we think we need some
 475  * more memory
 476  */
 477
 478 static int shrink_dqcache_memory(int nr, unsigned int gfp_mask)
 479 {
 480         int ret;
 481
 482         spin_lock(&dq_list_lock);
 483         if (nr)
 484                 prune_dqcache(nr);
 485         ret = dqstats.allocated_dquots;
 486         spin_unlock(&dq_list_lock);
 487         return ret;
 488 }
 489
 490 /*
 491  * Put reference to dquot
 492  * NOTE: If you change this function please check whether dqput_blocks() works right...
 493  * MUST be called with either dqptr_sem or dqonoff_sem held
 494  */
 495 static void dqput(struct dquot *dquot)
 496 {
 497         if (!dquot)
 498                 return;
 499 #ifdef __DQUOT_PARANOIA
 500         if (!atomic_read(&dquot->dq_count)) {
 501                 printk("VFS: dqput: trying to free free dquot\n");
 502                 printk("VFS: device %s, dquot of %s %d\n",
 503                         dquot->dq_sb->s_id,
 504                         quotatypes[dquot->dq_type],
 505                         dquot->dq_id);
 506                 BUG();
 507         }
 508 #endif
 509
 510         spin_lock(&dq_list_lock);
 511         dqstats.drops++;
 512         spin_unlock(&dq_list_lock);
 513 we_slept:
 514         spin_lock(&dq_list_lock);
 515         if (atomic_read(&dquot->dq_count) > 1) {
 516                 /* We have more than one user... nothing to do */
 517                 atomic_dec(&dquot->dq_count);
 518                 spin_unlock(&dq_list_lock);
 519                 return;
 520         }
 521         /* Need to release dquot? */
 522         if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) {
 523                 spin_unlock(&dq_list_lock);
 524                 /* Commit dquot before releasing */
 525                 dquot->dq_sb->dq_op->write_dquot(dquot);
 526                 goto we_slept;
 527         }
 528         /* Clear flag in case dquot was inactive (something bad happened) */
 529         clear_dquot_dirty(dquot);
 530         if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
 531                 spin_unlock(&dq_list_lock);
 532                 dquot_release(dquot);
 533                 goto we_slept;
 534         }
 535         atomic_dec(&dquot->dq_count);
 536 #ifdef __DQUOT_PARANOIA
 537         /* sanity check */
 538         if (!list_empty(&dquot->dq_free))
 539                 BUG();
 540 #endif
 541         put_dquot_last(dquot);
 542         spin_unlock(&dq_list_lock);
 543 }
 544
 545 static struct dquot *get_empty_dquot(struct super_block *sb, int type)
 546 {
 547         struct dquot *dquot;
 548
 549         dquot = kmem_cache_alloc(dquot_cachep, SLAB_KERNEL);
 550         if(!dquot)
 551                 return NODQUOT;
 552
 553         memset((caddr_t)dquot, 0, sizeof(struct dquot));
 554         sema_init(&dquot->dq_lock, 1);
 555         INIT_LIST_HEAD(&dquot->dq_free);
 556         INIT_LIST_HEAD(&dquot->dq_inuse);
 557         INIT_HLIST_NODE(&dquot->dq_hash);
 558         INIT_LIST_HEAD(&dquot->dq_dirty);
 559         dquot->dq_sb = sb;
 560         dquot->dq_type = type;
 561         atomic_set(&dquot->dq_count, 1);
 562
 563         return dquot;
 564 }
 565
 566 /*
 567  * Get reference to dquot
 568  * MUST be called with either dqptr_sem or dqonoff_sem held
 569  */
 570 static struct dquot *dqget(struct super_block *sb, unsigned int id, int type)
 571 {
 572         unsigned int hashent = hashfn(sb, id, type);
 573         struct dquot *dquot, *empty = NODQUOT;
 574
 575         if (!sb_has_quota_enabled(sb, type))
 576                 return NODQUOT;
 577 we_slept:
 578         spin_lock(&dq_list_lock);
 579         if ((dquot = find_dquot(hashent, sb, id, type)) == NODQUOT) {
 580                 if (empty == NODQUOT) {
 581                         spin_unlock(&dq_list_lock);
 582                         if ((empty = get_empty_dquot(sb, type)) == NODQUOT)
 583                                 schedule();     /* Try to wait for a moment... */
 584                         goto we_slept;
 585                 }
 586                 dquot = empty;
 587                 dquot->dq_id = id;
 588                 /* all dquots go on the inuse_list */
 589                 put_inuse(dquot);
 590                 /* hash it first so it can be found */
 591                 insert_dquot_hash(dquot);
 592                 dqstats.lookups++;
 593                 spin_unlock(&dq_list_lock);
 594         } else {
 595                 if (!atomic_read(&dquot->dq_count))
 596                         remove_free_dquot(dquot);
 597                 atomic_inc(&dquot->dq_count);
 598                 dqstats.cache_hits++;
 599                 dqstats.lookups++;
 600                 spin_unlock(&dq_list_lock);
 601                 if (empty)
 602                         kmem_cache_free(dquot_cachep, empty);
 603         }
 604         /* Wait for dq_lock - after this we know that either dquot_release() is already
 605          * finished or it will be canceled due to dq_count > 1 test */
 606         wait_on_dquot(dquot);
 607         /* Read the dquot and instantiate it (everything done only if needed) */
 608         if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_acquire(dquot) < 0) {
 609                 dqput(dquot);
 610                 return NODQUOT;
 611         }
 612 #ifdef __DQUOT_PARANOIA
 613         if (!dquot->dq_sb)      /* Has somebody invalidated entry under us? */
 614                 BUG();
 615 #endif
 616
 617         return dquot;
 618 }
 619
 620 static int dqinit_needed(struct inode *inode, int type)
 621 {
 622         int cnt;
 623
 624         if (IS_NOQUOTA(inode))
 625                 return 0;
 626         if (type != -1)
 627                 return inode->i_dquot[type] == NODQUOT;
 628         for (cnt = 0; cnt < MAXQUOTAS; cnt++)
 629                 if (inode->i_dquot[cnt] == NODQUOT)
 630                         return 1;
 631         return 0;
 632 }
 633
 634 /* This routine is guarded by dqonoff_sem semaphore */
 635 static void add_dquot_ref(struct super_block *sb, int type)
 636 {
 637         struct list_head *p;
 638
 639 restart:
 640         file_list_lock();
 641         list_for_each(p, &sb->s_files) {
 642                 struct file *filp = list_entry(p, struct file, f_list);
 643                 struct inode *inode = filp->f_dentry->d_inode;
 644                 if (filp->f_mode & FMODE_WRITE && dqinit_needed(inode, type)) {
 645                         struct dentry *dentry = dget(filp->f_dentry);
 646                         file_list_unlock();
 647                         sb->dq_op->initialize(inode, type);
 648                         dput(dentry);
 649                         /* As we may have blocked we had better restart... */
 650                         goto restart;
 651                 }
 652         }
 653         file_list_unlock();
 654 }
 655
 656 /* Return 0 if dqput() won't block (note that 1 doesn't necessarily mean blocking) */
 657 static inline int dqput_blocks(struct dquot *dquot)
 658 {
 659         if (atomic_read(&dquot->dq_count) <= 1)
 660                 return 1;
 661         return 0;
 662 }
 663
 664 /* Remove references to dquots from inode - add dquot to list for freeing if needed */
 665 /* We can't race with anybody because we hold dqptr_sem for writing... */
 666 int remove_inode_dquot_ref(struct inode *inode, int type, struct list_head *tofree_head)
 667 {
 668         struct dquot *dquot = inode->i_dquot[type];
 669         int cnt;
 670
 671         inode->i_dquot[type] = NODQUOT;
 672         /* any other quota in use? */
 673         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
 674                 if (inode->i_dquot[cnt] != NODQUOT)
 675                         goto put_it;
 676         }
 677         inode->i_flags &= ~S_QUOTA;
 678 put_it:
 679         if (dquot != NODQUOT) {
 680                 if (dqput_blocks(dquot)) {
 681 #ifdef __DQUOT_PARANOIA
 682                         if (atomic_read(&dquot->dq_count) != 1)
 683                                 printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count));
 684 #endif
 685                         spin_lock(&dq_list_lock);
 686                         list_add(&dquot->dq_free, tofree_head); /* As dquot must have currently users it can't be on the free list... */
 687                         spin_unlock(&dq_list_lock);
 688                         return 1;
 689                 }
 690                 else
 691                         dqput(dquot);   /* We have guaranteed we won't block */
 692         }
 693         return 0;
 694 }
 695
 696 /* Free list of dquots - called from inode.c */
 697 /* dquots are removed from inodes, no new references can be got so we are the only ones holding reference */
 698 static void put_dquot_list(struct list_head *tofree_head)
 699 {
 700         struct list_head *act_head;
 701         struct dquot *dquot;
 702
 703         act_head = tofree_head->next;
 704         /* So now we have dquots on the list... Just free them */
 705         while (act_head != tofree_head) {
 706                 dquot = list_entry(act_head, struct dquot, dq_free);
 707                 act_head = act_head->next;
 708                 list_del_init(&dquot->dq_free); /* Remove dquot from the list so we won't have problems... */
 709                 dqput(dquot);
 710         }
 711 }
 712
 713 /* Function in inode.c - remove pointers to dquots in icache */
 714 extern void remove_dquot_ref(struct super_block *, int, struct list_head *);
 715
 716 /* Gather all references from inodes and drop them */
 717 static void drop_dquot_ref(struct super_block *sb, int type)
 718 {
 719         LIST_HEAD(tofree_head);
 720
 721         down_write(&sb_dqopt(sb)->dqptr_sem);
 722         remove_dquot_ref(sb, type, &tofree_head);
 723         up_write(&sb_dqopt(sb)->dqptr_sem);
 724         put_dquot_list(&tofree_head);
 725 }
 726
 727 static inline void dquot_incr_inodes(struct dquot *dquot, unsigned long number)
 728 {
 729         dquot->dq_dqb.dqb_curinodes += number;
 730 }
 731
 732 static inline void dquot_incr_space(struct dquot *dquot, qsize_t number)
 733 {
 734         dquot->dq_dqb.dqb_curspace += number;
 735 }
 736
 737 static inline void dquot_decr_inodes(struct dquot *dquot, unsigned long number)
 738 {
 739         if (dquot->dq_dqb.dqb_curinodes > number)
 740                 dquot->dq_dqb.dqb_curinodes -= number;
 741         else
 742                 dquot->dq_dqb.dqb_curinodes = 0;
 743         if (dquot->dq_dqb.dqb_curinodes < dquot->dq_dqb.dqb_isoftlimit)
 744                 dquot->dq_dqb.dqb_itime = (time_t) 0;
 745         clear_bit(DQ_INODES_B, &dquot->dq_flags);
 746 }
 747
 748 static inline void dquot_decr_space(struct dquot *dquot, qsize_t number)
 749 {
 750         if (dquot->dq_dqb.dqb_curspace > number)
 751                 dquot->dq_dqb.dqb_curspace -= number;
 752         else
 753                 dquot->dq_dqb.dqb_curspace = 0;
 754         if (toqb(dquot->dq_dqb.dqb_curspace) < dquot->dq_dqb.dqb_bsoftlimit)
 755                 dquot->dq_dqb.dqb_btime = (time_t) 0;
 756         clear_bit(DQ_BLKS_B, &dquot->dq_flags);
 757 }
 758
 759 static inline int need_print_warning(struct dquot *dquot)
 760 {
 761         switch (dquot->dq_type) {
 762                 case USRQUOTA:
 763                         return current->fsuid == dquot->dq_id;
 764                 case GRPQUOTA:
 765                         return in_group_p(dquot->dq_id);
 766         }
 767         return 0;
 768 }
 769
 770 /* Values of warnings */
 771 #define NOWARN 0
 772 #define IHARDWARN 1
 773 #define ISOFTLONGWARN 2
 774 #define ISOFTWARN 3
 775 #define BHARDWARN 4
 776 #define BSOFTLONGWARN 5
 777 #define BSOFTWARN 6
 778
 779 /* Print warning to user which exceeded quota */
 780 static void print_warning(struct dquot *dquot, const char warntype)
 781 {
 782         char *msg = NULL;
 783         int flag = (warntype == BHARDWARN || warntype == BSOFTLONGWARN) ? DQ_BLKS_B :
 784           ((warntype == IHARDWARN || warntype == ISOFTLONGWARN) ? DQ_INODES_B : 0);
 785
 786         if (!need_print_warning(dquot) || (flag && test_and_set_bit(flag, &dquot->dq_flags)))
 787                 return;
 788         tty_write_message(current->signal->tty, dquot->dq_sb->s_id);
 789         if (warntype == ISOFTWARN || warntype == BSOFTWARN)
 790                 tty_write_message(current->signal->tty, ": warning, ");
 791         else
 792                 tty_write_message(current->signal->tty, ": write failed, ");
 793         tty_write_message(current->signal->tty, quotatypes[dquot->dq_type]);
 794         switch (warntype) {
 795                 case IHARDWARN:
 796                         msg = " file limit reached.\n";
 797                         break;
 798                 case ISOFTLONGWARN:
 799                         msg = " file quota exceeded too long.\n";
 800                         break;
 801                 case ISOFTWARN:
 802                         msg = " file quota exceeded.\n";
 803                         break;
 804                 case BHARDWARN:
 805                         msg = " block limit reached.\n";
 806                         break;
 807                 case BSOFTLONGWARN:
 808                         msg = " block quota exceeded too long.\n";
 809                         break;
 810                 case BSOFTWARN:
 811                         msg = " block quota exceeded.\n";
 812                         break;
 813         }
 814         tty_write_message(current->signal->tty, msg);
 815 }
 816
 817 static inline void flush_warnings(struct dquot **dquots, char *warntype)
 818 {
 819         int i;
 820
 821         for (i = 0; i < MAXQUOTAS; i++)
 822                 if (dquots[i] != NODQUOT && warntype[i] != NOWARN)
 823                         print_warning(dquots[i], warntype[i]);
 824 }
 825
 826 static inline char ignore_hardlimit(struct dquot *dquot)
 827 {
 828         struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type];
 829
 830         return capable(CAP_SYS_RESOURCE) &&
 831             (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || !(info->dqi_flags & V1_DQF_RSQUASH));
 832 }
 833
 834 /* needs dq_data_lock */
 835 static int check_idq(struct dquot *dquot, ulong inodes, char *warntype)
 836 {
 837         *warntype = NOWARN;
 838         if (inodes <= 0 || test_bit(DQ_FAKE_B, &dquot->dq_flags))
 839                 return QUOTA_OK;
 840
 841         if (dquot->dq_dqb.dqb_ihardlimit &&
 842            (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_ihardlimit &&
 843             !ignore_hardlimit(dquot)) {
 844                 *warntype = IHARDWARN;
 845                 return NO_QUOTA;
 846         }
 847
 848         if (dquot->dq_dqb.dqb_isoftlimit &&
 849            (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_isoftlimit &&
 850             dquot->dq_dqb.dqb_itime && get_seconds() >= dquot->dq_dqb.dqb_itime &&
 851             !ignore_hardlimit(dquot)) {
 852                 *warntype = ISOFTLONGWARN;
 853                 return NO_QUOTA;
 854         }
 855
 856         if (dquot->dq_dqb.dqb_isoftlimit &&
 857            (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_isoftlimit &&
 858             dquot->dq_dqb.dqb_itime == 0) {
 859                 *warntype = ISOFTWARN;
 860                 dquot->dq_dqb.dqb_itime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace;
 861         }
 862
 863         return QUOTA_OK;
 864 }
 865
 866 /* needs dq_data_lock */
 867 static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype)
 868 {
 869         *warntype = 0;
 870         if (space <= 0 || test_bit(DQ_FAKE_B, &dquot->dq_flags))
 871                 return QUOTA_OK;
 872
 873         if (dquot->dq_dqb.dqb_bhardlimit &&
 874            toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bhardlimit &&
 875             !ignore_hardlimit(dquot)) {
 876                 if (!prealloc)
 877                         *warntype = BHARDWARN;
 878                 return NO_QUOTA;
 879         }
 880
 881         if (dquot->dq_dqb.dqb_bsoftlimit &&
 882            toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit &&
 883             dquot->dq_dqb.dqb_btime && get_seconds() >= dquot->dq_dqb.dqb_btime &&
 884             !ignore_hardlimit(dquot)) {
 885                 if (!prealloc)
 886                         *warntype = BSOFTLONGWARN;
 887                 return NO_QUOTA;
 888         }
 889
 890         if (dquot->dq_dqb.dqb_bsoftlimit &&
 891            toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit &&
 892             dquot->dq_dqb.dqb_btime == 0) {
 893                 if (!prealloc) {
 894                         *warntype = BSOFTWARN;
 895                         dquot->dq_dqb.dqb_btime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_bgrace;
 896                 }
 897                 else
 898                         /*
 899                          * We don't allow preallocation to exceed softlimit so exceeding will
 900                          * be always printed
 901                          */
 902                         return NO_QUOTA;
 903         }
 904
 905         return QUOTA_OK;
 906 }
 907
 908 /*
 909  *      Initialize quota pointers in inode
 910  *      Transaction must be started at entry
 911  */
 912 int dquot_initialize(struct inode *inode, int type)
 913 {
 914         unsigned int id = 0;
 915         int cnt, ret = 0;
 916
 917         /* First test before acquiring semaphore - solves deadlocks when we
 918          * re-enter the quota code and are already holding the semaphore */
 919         if (IS_NOQUOTA(inode))
 920                 return 0;
 921         down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
 922         /* Having dqptr_sem we know NOQUOTA flags can't be altered... */
 923         if (IS_NOQUOTA(inode))
 924                 goto out_err;
 925         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
 926                 if (type != -1 && cnt != type)
 927                         continue;
 928                 if (inode->i_dquot[cnt] == NODQUOT) {
 929                         switch (cnt) {
 930                                 case USRQUOTA:
 931                                         id = inode->i_uid;
 932                                         break;
 933                                 case GRPQUOTA:
 934                                         id = inode->i_gid;
 935                                         break;
 936                         }
 937                         inode->i_dquot[cnt] = dqget(inode->i_sb, id, cnt);
 938                         if (inode->i_dquot[cnt])
 939                                 inode->i_flags |= S_QUOTA;
 940                 }
 941         }
 942 out_err:
 943         up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
 944         return ret;
 945 }
 946
 947 /*
 948  *      Release all quotas referenced by inode
 949  *      Transaction must be started at an entry
 950  */
 951 int dquot_drop(struct inode *inode)
 952 {
 953         int cnt;
 954
 955         down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
 956         inode->i_flags &= ~S_QUOTA;
 957         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
 958                 if (inode->i_dquot[cnt] != NODQUOT) {
 959                         dqput(inode->i_dquot[cnt]);
 960                         inode->i_dquot[cnt] = NODQUOT;
 961                 }
 962         }
 963         up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
 964         return 0;
 965 }
 966
 967 /*
 968  * Following four functions update i_blocks+i_bytes fields and
 969  * quota information (together with appropriate checks)
 970  * NOTE: We absolutely rely on the fact that caller dirties
 971  * the inode (usually macros in quotaops.h care about this) and
 972  * holds a handle for the current transaction so that dquot write and
 973  * inode write go into the same transaction.
 974  */
 975
 976 /*
 977  * This operation can block, but only after everything is updated
 978  */
 979 int dquot_alloc_space(struct inode *inode, qsize_t number, int warn)
 980 {
 981         int cnt, ret = NO_QUOTA;
 982         char warntype[MAXQUOTAS];
 983
 984         /* First test before acquiring semaphore - solves deadlocks when we
 985          * re-enter the quota code and are already holding the semaphore */
 986         if (IS_NOQUOTA(inode)) {
 987 out_add:
 988                 inode_add_bytes(inode, number);
 989                 return QUOTA_OK;
 990         }
 991         for (cnt = 0; cnt < MAXQUOTAS; cnt++)
 992                 warntype[cnt] = NOWARN;
 993
 994         down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
 995         if (IS_NOQUOTA(inode)) {        /* Now we can do reliable test... */
 996                 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
 997                 goto out_add;
 998         }
 999         spin_lock(&dq_data_lock);
1000         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1001                 if (inode->i_dquot[cnt] == NODQUOT)
1002                         continue;
1003                 if (check_bdq(inode->i_dquot[cnt], number, warn, warntype+cnt) == NO_QUOTA)
1004                         goto warn_put_all;
1005         }
1006         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1007                 if (inode->i_dquot[cnt] == NODQUOT)
1008                         continue;
1009                 dquot_incr_space(inode->i_dquot[cnt], number);
1010         }
1011         inode_add_bytes(inode, number);
1012         ret = QUOTA_OK;
1013 warn_put_all:
1014         spin_unlock(&dq_data_lock);
1015         if (ret == QUOTA_OK)
1016                 /* Dirtify all the dquots - this can block when journalling */
1017                 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1018                         if (inode->i_dquot[cnt])
1019                                 mark_dquot_dirty(inode->i_dquot[cnt]);
1020         flush_warnings(inode->i_dquot, warntype);
1021         up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1022         return ret;
1023 }
1024
1025 /*
1026  * This operation can block, but only after everything is updated
1027  */
1028 int dquot_alloc_inode(const struct inode *inode, unsigned long number)
1029 {
1030         int cnt, ret = NO_QUOTA;
1031         char warntype[MAXQUOTAS];
1032
1033         /* First test before acquiring semaphore - solves deadlocks when we
1034          * re-enter the quota code and are already holding the semaphore */
1035         if (IS_NOQUOTA(inode))
1036                 return QUOTA_OK;
1037         for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1038                 warntype[cnt] = NOWARN;
1039         down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1040         if (IS_NOQUOTA(inode)) {
1041                 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1042                 return QUOTA_OK;
1043         }
1044         spin_lock(&dq_data_lock);
1045         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1046                 if (inode->i_dquot[cnt] == NODQUOT)
1047                         continue;
1048                 if (check_idq(inode->i_dquot[cnt], number, warntype+cnt) == NO_QUOTA)
1049                         goto warn_put_all;
1050         }
1051
1052         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1053                 if (inode->i_dquot[cnt] == NODQUOT)
1054                         continue;
1055                 dquot_incr_inodes(inode->i_dquot[cnt], number);
1056         }
1057         ret = QUOTA_OK;
1058 warn_put_all:
1059         spin_unlock(&dq_data_lock);
1060         if (ret == QUOTA_OK)
1061                 /* Dirtify all the dquots - this can block when journalling */
1062                 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1063                         if (inode->i_dquot[cnt])
1064                                 mark_dquot_dirty(inode->i_dquot[cnt]);
1065         flush_warnings((struct dquot **)inode->i_dquot, warntype);
1066         up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1067         return ret;
1068 }
1069
1070 /*
1071  * This is a non-blocking operation.
1072  */
1073 int dquot_free_space(struct inode *inode, qsize_t number)
1074 {
1075         unsigned int cnt;
1076
1077         /* First test before acquiring semaphore - solves deadlocks when we
1078          * re-enter the quota code and are already holding the semaphore */
1079         if (IS_NOQUOTA(inode)) {
1080 out_sub:
1081                 inode_sub_bytes(inode, number);
1082                 return QUOTA_OK;
1083         }
1084         down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1085         /* Now recheck reliably when holding dqptr_sem */
1086         if (IS_NOQUOTA(inode)) {
1087                 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1088                 goto out_sub;
1089         }
1090         spin_lock(&dq_data_lock);
1091         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1092                 if (inode->i_dquot[cnt] == NODQUOT)
1093                         continue;
1094                 dquot_decr_space(inode->i_dquot[cnt], number);
1095         }
1096         inode_sub_bytes(inode, number);
1097         spin_unlock(&dq_data_lock);
1098         /* Dirtify all the dquots - this can block when journalling */
1099         for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1100                 if (inode->i_dquot[cnt])
1101                         mark_dquot_dirty(inode->i_dquot[cnt]);
1102         up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1103         return QUOTA_OK;
1104 }
1105
1106 /*
1107  * This is a non-blocking operation.
1108  */
1109 int dquot_free_inode(const struct inode *inode, unsigned long number)
1110 {
1111         unsigned int cnt;
1112
1113         /* First test before acquiring semaphore - solves deadlocks when we
1114          * re-enter the quota code and are already holding the semaphore */
1115         if (IS_NOQUOTA(inode))
1116                 return QUOTA_OK;
1117         down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1118         /* Now recheck reliably when holding dqptr_sem */
1119         if (IS_NOQUOTA(inode)) {
1120                 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1121                 return QUOTA_OK;
1122         }
1123         spin_lock(&dq_data_lock);
1124         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1125                 if (inode->i_dquot[cnt] == NODQUOT)
1126                         continue;
1127                 dquot_decr_inodes(inode->i_dquot[cnt], number);
1128         }
1129         spin_unlock(&dq_data_lock);
1130         /* Dirtify all the dquots - this can block when journalling */
1131         for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1132                 if (inode->i_dquot[cnt])
1133                         mark_dquot_dirty(inode->i_dquot[cnt]);
1134         up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1135         return QUOTA_OK;
1136 }
1137
1138 /*
1139  * Transfer the number of inode and blocks from one diskquota to an other.
1140  *
1141  * This operation can block, but only after everything is updated
1142  */
1143 int dquot_transfer(struct inode *inode, struct iattr *iattr)
1144 {
1145         qsize_t space;
1146         struct dquot *transfer_from[MAXQUOTAS];
1147         struct dquot *transfer_to[MAXQUOTAS];
1148         int cnt, ret = NO_QUOTA, chuid = (iattr->ia_valid & ATTR_UID) && inode->i_uid != iattr->ia_uid,
1149             chgid = (iattr->ia_valid & ATTR_GID) && inode->i_gid != iattr->ia_gid;
1150         char warntype[MAXQUOTAS];
1151
1152         /* First test before acquiring semaphore - solves deadlocks when we
1153          * re-enter the quota code and are already holding the semaphore */
1154         if (IS_NOQUOTA(inode))
1155                 return QUOTA_OK;
1156         /* Clear the arrays */
1157         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1158                 transfer_to[cnt] = transfer_from[cnt] = NODQUOT;
1159                 warntype[cnt] = NOWARN;
1160         }
1161         down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1162         /* Now recheck reliably when holding dqptr_sem */
1163         if (IS_NOQUOTA(inode)) {        /* File without quota accounting? */
1164                 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1165                 return QUOTA_OK;
1166         }
1167         /* First build the transfer_to list - here we can block on
1168          * reading/instantiating of dquots.  We know that the transaction for
1169          * us was already started so we don't violate lock ranking here */
1170         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1171                 switch (cnt) {
1172                         case USRQUOTA:
1173                                 if (!chuid)
1174                                         continue;
1175                                 transfer_to[cnt] = dqget(inode->i_sb, iattr->ia_uid, cnt);
1176                                 break;
1177                         case GRPQUOTA:
1178                                 if (!chgid)
1179                                         continue;
1180                                 transfer_to[cnt] = dqget(inode->i_sb, iattr->ia_gid, cnt);
1181                                 break;
1182                 }
1183         }
1184         spin_lock(&dq_data_lock);
1185         space = inode_get_bytes(inode);
1186         /* Build the transfer_from list and check the limits */
1187         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1188                 if (transfer_to[cnt] == NODQUOT)
1189                         continue;
1190                 transfer_from[cnt] = inode->i_dquot[cnt];
1191                 if (check_idq(transfer_to[cnt], 1, warntype+cnt) == NO_QUOTA ||
1192                     check_bdq(transfer_to[cnt], space, 0, warntype+cnt) == NO_QUOTA)
1193                         goto warn_put_all;
1194         }
1195
1196         /*
1197          * Finally perform the needed transfer from transfer_from to transfer_to
1198          */
1199         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1200                 /*
1201                  * Skip changes for same uid or gid or for turned off quota-type.
1202                  */
1203                 if (transfer_to[cnt] == NODQUOT)
1204                         continue;
1205
1206                 dquot_decr_inodes(transfer_from[cnt], 1);
1207                 dquot_decr_space(transfer_from[cnt], space);
1208
1209                 dquot_incr_inodes(transfer_to[cnt], 1);
1210                 dquot_incr_space(transfer_to[cnt], space);
1211
1212                 inode->i_dquot[cnt] = transfer_to[cnt];
1213         }
1214         ret = QUOTA_OK;
1215 warn_put_all:
1216         spin_unlock(&dq_data_lock);
1217         /* Dirtify all the dquots - this can block when journalling */
1218         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1219                 if (transfer_from[cnt])
1220                         mark_dquot_dirty(transfer_from[cnt]);
1221                 if (transfer_to[cnt])
1222                         mark_dquot_dirty(transfer_to[cnt]);
1223         }
1224         flush_warnings(transfer_to, warntype);
1225
1226         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1227                 if (ret == QUOTA_OK && transfer_from[cnt] != NODQUOT)
1228                         dqput(transfer_from[cnt]);
1229                 if (ret == NO_QUOTA && transfer_to[cnt] != NODQUOT)
1230                         dqput(transfer_to[cnt]);
1231         }
1232         up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1233         return ret;
1234 }
1235
1236 /*
1237  * Write info of quota file to disk
1238  */
1239 int dquot_commit_info(struct super_block *sb, int type)
1240 {
1241         int ret;
1242         struct quota_info *dqopt = sb_dqopt(sb);
1243
1244         down(&dqopt->dqio_sem);
1245         ret = dqopt->ops[type]->write_file_info(sb, type);
1246         up(&dqopt->dqio_sem);
1247         return ret;
1248 }
1249
1250 /*
1251  * Definitions of diskquota operations.
1252  */
1253 struct dquot_operations dquot_operations = {
1254         .initialize     = dquot_initialize,
1255         .drop           = dquot_drop,
1256         .alloc_space    = dquot_alloc_space,
1257         .alloc_inode    = dquot_alloc_inode,
1258         .free_space     = dquot_free_space,
1259         .free_inode     = dquot_free_inode,
1260         .transfer       = dquot_transfer,
1261         .write_dquot    = dquot_commit,
1262         .mark_dirty     = dquot_mark_dquot_dirty,
1263         .write_info     = dquot_commit_info
1264 };
1265
1266 static inline void set_enable_flags(struct quota_info *dqopt, int type)
1267 {
1268         switch (type) {
1269                 case USRQUOTA:
1270                         dqopt->flags |= DQUOT_USR_ENABLED;
1271                         break;
1272                 case GRPQUOTA:
1273                         dqopt->flags |= DQUOT_GRP_ENABLED;
1274                         break;
1275         }
1276 }
1277
1278 static inline void reset_enable_flags(struct quota_info *dqopt, int type)
1279 {
1280         switch (type) {
1281                 case USRQUOTA:
1282                         dqopt->flags &= ~DQUOT_USR_ENABLED;
1283                         break;
1284                 case GRPQUOTA:
1285                         dqopt->flags &= ~DQUOT_GRP_ENABLED;
1286                         break;
1287         }
1288 }
1289
1290 /*
1291  * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount)
1292  */
1293 int vfs_quota_off(struct super_block *sb, int type)
1294 {
1295         int cnt;
1296         struct quota_info *dqopt = sb_dqopt(sb);
1297
1298         /* We need to serialize quota_off() for device */
1299         down(&dqopt->dqonoff_sem);
1300         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1301                 if (type != -1 && cnt != type)
1302                         continue;
1303                 if (!sb_has_quota_enabled(sb, cnt))
1304                         continue;
1305                 reset_enable_flags(dqopt, cnt);
1306
1307                 /* Note: these are blocking operations */
1308                 drop_dquot_ref(sb, cnt);
1309                 invalidate_dquots(sb, cnt);
1310                 /*
1311                  * Now all dquots should be invalidated, all writes done so we should be only
1312                  * users of the info. No locks needed.
1313                  */
1314                 if (info_dirty(&dqopt->info[cnt]))
1315                         sb->dq_op->write_info(sb, cnt);
1316                 if (dqopt->ops[cnt]->free_file_info)
1317                         dqopt->ops[cnt]->free_file_info(sb, cnt);
1318                 put_quota_format(dqopt->info[cnt].dqi_format);
1319
1320                 fput(dqopt->files[cnt]);
1321                 dqopt->files[cnt] = NULL;
1322                 dqopt->info[cnt].dqi_flags = 0;
1323                 dqopt->info[cnt].dqi_igrace = 0;
1324                 dqopt->info[cnt].dqi_bgrace = 0;
1325                 dqopt->ops[cnt] = NULL;
1326         }
1327         up(&dqopt->dqonoff_sem);
1328         return 0;
1329 }
1330
1331 /*
1332  *      Turn quotas on on a device
1333  */
1334
1335 /* Helper function when we already have file open */
1336 static int vfs_quota_on_file(struct file *f, int type, int format_id)
1337 {
1338         struct quota_format_type *fmt = find_quota_format(format_id);
1339         struct inode *inode;
1340         struct super_block *sb = f->f_dentry->d_sb;
1341         struct quota_info *dqopt = sb_dqopt(sb);
1342         struct dquot *to_drop[MAXQUOTAS];
1343         int error, cnt;
1344         unsigned int oldflags;
1345
1346         if (!fmt)
1347                 return -ESRCH;
1348         error = -EIO;
1349         if (!f->f_op || !f->f_op->read || !f->f_op->write)
1350                 goto out_fmt;
1351         inode = f->f_dentry->d_inode;
1352         error = -EACCES;
1353         if (!S_ISREG(inode->i_mode))
1354                 goto out_fmt;
1355
1356         down(&dqopt->dqonoff_sem);
1357         if (sb_has_quota_enabled(sb, type)) {
1358                 error = -EBUSY;
1359                 goto out_lock;
1360         }
1361         oldflags = inode->i_flags;
1362         dqopt->files[type] = f;
1363         error = -EINVAL;
1364         if (!fmt->qf_ops->check_quota_file(sb, type))
1365                 goto out_file_init;
1366         /* We don't want quota and atime on quota files (deadlocks possible) */
1367         down_write(&dqopt->dqptr_sem);
1368         inode->i_flags |= S_NOQUOTA | S_NOATIME;
1369         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1370                 to_drop[cnt] = inode->i_dquot[cnt];
1371                 inode->i_dquot[cnt] = NODQUOT;
1372         }
1373         inode->i_flags &= ~S_QUOTA;
1374         up_write(&dqopt->dqptr_sem);
1375         /* We must put dquots outside of dqptr_sem because we may need to
1376          * start transaction for dquot_release() */
1377         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1378                 if (to_drop[cnt])
1379                         dqput(to_drop[cnt]);
1380         }
1381
1382         dqopt->ops[type] = fmt->qf_ops;
1383         dqopt->info[type].dqi_format = fmt;
1384         INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list);
1385         down(&dqopt->dqio_sem);
1386         if ((error = dqopt->ops[type]->read_file_info(sb, type)) < 0) {
1387                 up(&dqopt->dqio_sem);
1388                 goto out_file_init;
1389         }
1390         up(&dqopt->dqio_sem);
1391         set_enable_flags(dqopt, type);
1392
1393         add_dquot_ref(sb, type);
1394         up(&dqopt->dqonoff_sem);
1395
1396         return 0;
1397
1398 out_file_init:
1399         inode->i_flags = oldflags;
1400         dqopt->files[type] = NULL;
1401 out_lock:
1402         up_write(&dqopt->dqptr_sem);
1403         up(&dqopt->dqonoff_sem);
1404 out_fmt:
1405         put_quota_format(fmt);
1406
1407         return error;
1408 }
1409
1410 /* Actual function called from quotactl() */
1411 int vfs_quota_on(struct super_block *sb, int type, int format_id, char *path)
1412 {
1413         struct file *f;
1414         int error;
1415
1416         f = filp_open(path, O_RDWR, 0600);
1417         if (IS_ERR(f))
1418                 return PTR_ERR(f);
1419         error = security_quota_on(f);
1420         if (error)
1421                 goto out_f;
1422         error = vfs_quota_on_file(f, type, format_id);
1423         if (!error)
1424                 return 0;
1425 out_f:
1426         filp_close(f, NULL);
1427         return error;
1428 }
1429
1430 /*
1431  * Function used by filesystems when filp_open() would fail (filesystem is
1432  * being mounted now). We will use a private file structure. Caller is
1433  * responsible that it's IO functions won't need vfsmnt structure or
1434  * some dentry tricks...
1435  */
1436 int vfs_quota_on_mount(int type, int format_id, struct dentry *dentry)
1437 {
1438         struct file *f;
1439         int error;
1440
1441         dget(dentry);   /* Get a reference for struct file */
1442         f = dentry_open(dentry, NULL, O_RDWR);
1443         if (IS_ERR(f)) {
1444                 error = PTR_ERR(f);
1445                 goto out_dentry;
1446         }
1447         error = vfs_quota_on_file(f, type, format_id);
1448         if (!error)
1449                 return 0;
1450         fput(f);
1451 out_dentry:
1452         dput(dentry);
1453         return error;
1454 }
1455
1456 /* Generic routine for getting common part of quota structure */
1457 static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di)
1458 {
1459         struct mem_dqblk *dm = &dquot->dq_dqb;
1460
1461         spin_lock(&dq_data_lock);
1462         di->dqb_bhardlimit = dm->dqb_bhardlimit;
1463         di->dqb_bsoftlimit = dm->dqb_bsoftlimit;
1464         di->dqb_curspace = dm->dqb_curspace;
1465         di->dqb_ihardlimit = dm->dqb_ihardlimit;
1466         di->dqb_isoftlimit = dm->dqb_isoftlimit;
1467         di->dqb_curinodes = dm->dqb_curinodes;
1468         di->dqb_btime = dm->dqb_btime;
1469         di->dqb_itime = dm->dqb_itime;
1470         di->dqb_valid = QIF_ALL;
1471         spin_unlock(&dq_data_lock);
1472 }
1473
1474 int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di)
1475 {
1476         struct dquot *dquot;
1477
1478         down(&sb_dqopt(sb)->dqonoff_sem);
1479         if (!(dquot = dqget(sb, id, type))) {
1480                 up(&sb_dqopt(sb)->dqonoff_sem);
1481                 return -ESRCH;
1482         }
1483         do_get_dqblk(dquot, di);
1484         dqput(dquot);
1485         up(&sb_dqopt(sb)->dqonoff_sem);
1486         return 0;
1487 }
1488
1489 /* Generic routine for setting common part of quota structure */
1490 static void do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
1491 {
1492         struct mem_dqblk *dm = &dquot->dq_dqb;
1493         int check_blim = 0, check_ilim = 0;
1494
1495         spin_lock(&dq_data_lock);
1496         if (di->dqb_valid & QIF_SPACE) {
1497                 dm->dqb_curspace = di->dqb_curspace;
1498                 check_blim = 1;
1499         }
1500         if (di->dqb_valid & QIF_BLIMITS) {
1501                 dm->dqb_bsoftlimit = di->dqb_bsoftlimit;
1502                 dm->dqb_bhardlimit = di->dqb_bhardlimit;
1503                 check_blim = 1;
1504         }
1505         if (di->dqb_valid & QIF_INODES) {
1506                 dm->dqb_curinodes = di->dqb_curinodes;
1507                 check_ilim = 1;
1508         }
1509         if (di->dqb_valid & QIF_ILIMITS) {
1510                 dm->dqb_isoftlimit = di->dqb_isoftlimit;
1511                 dm->dqb_ihardlimit = di->dqb_ihardlimit;
1512                 check_ilim = 1;
1513         }
1514         if (di->dqb_valid & QIF_BTIME)
1515                 dm->dqb_btime = di->dqb_btime;
1516         if (di->dqb_valid & QIF_ITIME)
1517                 dm->dqb_itime = di->dqb_itime;
1518
1519         if (check_blim) {
1520                 if (!dm->dqb_bsoftlimit || toqb(dm->dqb_curspace) < dm->dqb_bsoftlimit) {
1521                         dm->dqb_btime = 0;
1522                         clear_bit(DQ_BLKS_B, &dquot->dq_flags);
1523                 }
1524                 else if (!(di->dqb_valid & QIF_BTIME))  /* Set grace only if user hasn't provided his own... */
1525                         dm->dqb_btime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_bgrace;
1526         }
1527         if (check_ilim) {
1528                 if (!dm->dqb_isoftlimit || dm->dqb_curinodes < dm->dqb_isoftlimit) {
1529                         dm->dqb_itime = 0;
1530                         clear_bit(DQ_INODES_B, &dquot->dq_flags);
1531                 }
1532                 else if (!(di->dqb_valid & QIF_ITIME))  /* Set grace only if user hasn't provided his own... */
1533                         dm->dqb_itime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace;
1534         }
1535         if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || dm->dqb_isoftlimit)
1536                 clear_bit(DQ_FAKE_B, &dquot->dq_flags);
1537         else
1538                 set_bit(DQ_FAKE_B, &dquot->dq_flags);
1539         spin_unlock(&dq_data_lock);
1540         mark_dquot_dirty(dquot);
1541 }
1542
1543 int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di)
1544 {
1545         struct dquot *dquot;
1546
1547         down(&sb_dqopt(sb)->dqonoff_sem);
1548         if (!(dquot = dqget(sb, id, type))) {
1549                 up(&sb_dqopt(sb)->dqonoff_sem);
1550                 return -ESRCH;
1551         }
1552         do_set_dqblk(dquot, di);
1553         dqput(dquot);
1554         up(&sb_dqopt(sb)->dqonoff_sem);
1555         return 0;
1556 }
1557
1558 /* Generic routine for getting common part of quota file information */
1559 int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
1560 {
1561         struct mem_dqinfo *mi;
1562
1563         down(&sb_dqopt(sb)->dqonoff_sem);
1564         if (!sb_has_quota_enabled(sb, type)) {
1565                 up(&sb_dqopt(sb)->dqonoff_sem);
1566                 return -ESRCH;
1567         }
1568         mi = sb_dqopt(sb)->info + type;
1569         spin_lock(&dq_data_lock);
1570         ii->dqi_bgrace = mi->dqi_bgrace;
1571         ii->dqi_igrace = mi->dqi_igrace;
1572         ii->dqi_flags = mi->dqi_flags & DQF_MASK;
1573         ii->dqi_valid = IIF_ALL;
1574         spin_unlock(&dq_data_lock);
1575         up(&sb_dqopt(sb)->dqonoff_sem);
1576         return 0;
1577 }
1578
1579 /* Generic routine for setting common part of quota file information */
1580 int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
1581 {
1582         struct mem_dqinfo *mi;
1583
1584         down(&sb_dqopt(sb)->dqonoff_sem);
1585         if (!sb_has_quota_enabled(sb, type)) {
1586                 up(&sb_dqopt(sb)->dqonoff_sem);
1587                 return -ESRCH;
1588         }
1589         mi = sb_dqopt(sb)->info + type;
1590         spin_lock(&dq_data_lock);
1591         if (ii->dqi_valid & IIF_BGRACE)
1592                 mi->dqi_bgrace = ii->dqi_bgrace;
1593         if (ii->dqi_valid & IIF_IGRACE)
1594                 mi->dqi_igrace = ii->dqi_igrace;
1595         if (ii->dqi_valid & IIF_FLAGS)
1596                 mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) | (ii->dqi_flags & DQF_MASK);
1597         spin_unlock(&dq_data_lock);
1598         mark_info_dirty(sb, type);
1599         /* Force write to disk */
1600         sb->dq_op->write_info(sb, type);
1601         up(&sb_dqopt(sb)->dqonoff_sem);
1602         return 0;
1603 }
1604
1605 struct quotactl_ops vfs_quotactl_ops = {
1606         .quota_on       = vfs_quota_on,
1607         .quota_off      = vfs_quota_off,
1608         .quota_sync     = vfs_quota_sync,
1609         .get_info       = vfs_get_dqinfo,
1610         .set_info       = vfs_set_dqinfo,
1611         .get_dqblk      = vfs_get_dqblk,
1612         .set_dqblk      = vfs_set_dqblk
1613 };
1614
1615 static ctl_table fs_dqstats_table[] = {
1616         {
1617                 .ctl_name       = FS_DQ_LOOKUPS,
1618                 .procname       = "lookups",
1619                 .data           = &dqstats.lookups,
1620                 .maxlen         = sizeof(int),
1621                 .mode           = 0444,
1622                 .proc_handler   = &proc_dointvec,
1623         },
1624         {
1625                 .ctl_name       = FS_DQ_DROPS,
1626                 .procname       = "drops",
1627                 .data           = &dqstats.drops,
1628                 .maxlen         = sizeof(int),
1629                 .mode           = 0444,
1630                 .proc_handler   = &proc_dointvec,
1631         },
1632         {
1633                 .ctl_name       = FS_DQ_READS,
1634                 .procname       = "reads",
1635                 .data           = &dqstats.reads,
1636                 .maxlen         = sizeof(int),
1637                 .mode           = 0444,
1638                 .proc_handler   = &proc_dointvec,
1639         },
1640         {
1641                 .ctl_name       = FS_DQ_WRITES,
1642                 .procname       = "writes",
1643                 .data           = &dqstats.writes,
1644                 .maxlen         = sizeof(int),
1645                 .mode           = 0444,
1646                 .proc_handler   = &proc_dointvec,
1647         },
1648         {
1649                 .ctl_name       = FS_DQ_CACHE_HITS,
1650                 .procname       = "cache_hits",
1651                 .data           = &dqstats.cache_hits,
1652                 .maxlen         = sizeof(int),
1653                 .mode           = 0444,
1654                 .proc_handler   = &proc_dointvec,
1655         },
1656         {
1657                 .ctl_name       = FS_DQ_ALLOCATED,
1658                 .procname       = "allocated_dquots",
1659                 .data           = &dqstats.allocated_dquots,
1660                 .maxlen         = sizeof(int),
1661                 .mode           = 0444,
1662                 .proc_handler   = &proc_dointvec,
1663         },
1664         {
1665                 .ctl_name       = FS_DQ_FREE,
1666                 .procname       = "free_dquots",
1667                 .data           = &dqstats.free_dquots,
1668                 .maxlen         = sizeof(int),
1669                 .mode           = 0444,
1670                 .proc_handler   = &proc_dointvec,
1671         },
1672         {
1673                 .ctl_name       = FS_DQ_SYNCS,
1674                 .procname       = "syncs",
1675                 .data           = &dqstats.syncs,
1676                 .maxlen         = sizeof(int),
1677                 .mode           = 0444,
1678                 .proc_handler   = &proc_dointvec,
1679         },
1680         { .ctl_name = 0 },
1681 };
1682
1683 static ctl_table fs_table[] = {
1684         {
1685                 .ctl_name       = FS_DQSTATS,
1686                 .procname       = "quota",
1687                 .mode           = 0555,
1688                 .child          = fs_dqstats_table,
1689         },
1690         { .ctl_name = 0 },
1691 };
1692
1693 static ctl_table sys_table[] = {
1694         {
1695                 .ctl_name       = CTL_FS,
1696                 .procname       = "fs",
1697                 .mode           = 0555,
1698                 .child          = fs_table,
1699         },
1700         { .ctl_name = 0 },
1701 };
1702
1703 /* SLAB cache for dquot structures */
1704 kmem_cache_t *dquot_cachep;
1705
1706 static int __init dquot_init(void)
1707 {
1708         int i;
1709         unsigned long nr_hash, order;
1710
1711         printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__);
1712
1713         register_sysctl_table(sys_table, 0);
1714
1715         dquot_cachep = kmem_cache_create("dquot",
1716                         sizeof(struct dquot), sizeof(unsigned long) * 4,
1717                         SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT, NULL, NULL);
1718         if (!dquot_cachep)
1719                 panic("Cannot create dquot SLAB cache");
1720
1721         order = 0;
1722         dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order);
1723         if (!dquot_hash)
1724                 panic("Cannot create dquot hash table");
1725
1726         /* Find power-of-two hlist_heads which can fit into allocation */
1727         nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head);
1728         dq_hash_bits = 0;
1729         do {
1730                 dq_hash_bits++;
1731         } while (nr_hash >> dq_hash_bits);
1732         dq_hash_bits--;
1733
1734         nr_hash = 1UL << dq_hash_bits;
1735         dq_hash_mask = nr_hash - 1;
1736         for (i = 0; i < nr_hash; i++)
1737                 INIT_HLIST_HEAD(dquot_hash + i);
1738
1739         printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n",
1740                         nr_hash, order, (PAGE_SIZE << order));
1741
1742         set_shrinker(DEFAULT_SEEKS, shrink_dqcache_memory);
1743
1744         return 0;
1745 }
1746 module_init(dquot_init);
1747
1748 EXPORT_SYMBOL(register_quota_format);
1749 EXPORT_SYMBOL(unregister_quota_format);
1750 EXPORT_SYMBOL(dqstats);
1751 EXPORT_SYMBOL(dq_list_lock);
1752 EXPORT_SYMBOL(dq_data_lock);
1753 EXPORT_SYMBOL(vfs_quota_on);
1754 EXPORT_SYMBOL(vfs_quota_on_mount);
1755 EXPORT_SYMBOL(vfs_quota_off);
1756 EXPORT_SYMBOL(vfs_quota_sync);
1757 EXPORT_SYMBOL(vfs_get_dqinfo);
1758 EXPORT_SYMBOL(vfs_set_dqinfo);
1759 EXPORT_SYMBOL(vfs_get_dqblk);
1760 EXPORT_SYMBOL(vfs_set_dqblk);
1761 EXPORT_SYMBOL(dquot_commit);
1762 EXPORT_SYMBOL(dquot_commit_info);
1763 EXPORT_SYMBOL(dquot_mark_dquot_dirty);
1764 EXPORT_SYMBOL(dquot_initialize);
1765 EXPORT_SYMBOL(dquot_drop);
1766 EXPORT_SYMBOL(dquot_alloc_space);
1767 EXPORT_SYMBOL(dquot_alloc_inode);
1768 EXPORT_SYMBOL(dquot_free_space);
1769 EXPORT_SYMBOL(dquot_free_inode);
1770 EXPORT_SYMBOL(dquot_transfer);