LXR linux/include/linux/quota.h

   1/*
   2 * Copyright (c) 1982, 1986 Regents of the University of California.
   3 * All rights reserved.
   4 *
   5 * This code is derived from software contributed to Berkeley by
   6 * Robert Elz at The University of Melbourne.
   7 *
   8 * Redistribution and use in source and binary forms, with or without
   9 * modification, are permitted provided that the following conditions
  10 * are met:
  11 * 1. Redistributions of source code must retain the above copyright
  12 *    notice, this list of conditions and the following disclaimer.
  13 * 2. Redistributions in binary form must reproduce the above copyright
  14 *    notice, this list of conditions and the following disclaimer in the
  15 *    documentation and/or other materials provided with the distribution.
  16 * 3. Neither the name of the University nor the names of its contributors
  17 *    may be used to endorse or promote products derived from this software
  18 *    without specific prior written permission.
  19 *
  20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30 * SUCH DAMAGE.
  31 */
  32#ifndef _LINUX_QUOTA_
  33#define _LINUX_QUOTA_
  34
  35#include <linux/list.h>
  36#include <linux/mutex.h>
  37#include <linux/rwsem.h>
  38#include <linux/spinlock.h>
  39#include <linux/wait.h>
  40#include <linux/percpu_counter.h>
  41
  42#include <linux/dqblk_xfs.h>
  43#include <linux/dqblk_v1.h>
  44#include <linux/dqblk_v2.h>
  45
  46#include <linux/atomic.h>
  47#include <linux/uidgid.h>
  48#include <linux/projid.h>
  49#include <uapi/linux/quota.h>
  50
  51#undef USRQUOTA
  52#undef GRPQUOTA
  53#undef PRJQUOTA
  54enum quota_type {
  55        USRQUOTA = 0,           /* element used for user quotas */
  56        GRPQUOTA = 1,           /* element used for group quotas */
  57        PRJQUOTA = 2,           /* element used for project quotas */
  58};
  59
  60/* Masks for quota types when used as a bitmask */
  61#define QTYPE_MASK_USR (1 << USRQUOTA)
  62#define QTYPE_MASK_GRP (1 << GRPQUOTA)
  63#define QTYPE_MASK_PRJ (1 << PRJQUOTA)
  64
  65typedef __kernel_uid32_t qid_t; /* Type in which we store ids in memory */
  66typedef long long qsize_t;      /* Type in which we store sizes */
  67
  68struct kqid {                   /* Type in which we store the quota identifier */
  69        union {
  70                kuid_t uid;
  71                kgid_t gid;
  72                kprojid_t projid;
  73        };
  74        enum quota_type type;  /* USRQUOTA (uid) or GRPQUOTA (gid) or PRJQUOTA (projid) */
  75};
  76
  77extern bool qid_eq(struct kqid left, struct kqid right);
  78extern bool qid_lt(struct kqid left, struct kqid right);
  79extern qid_t from_kqid(struct user_namespace *to, struct kqid qid);
  80extern qid_t from_kqid_munged(struct user_namespace *to, struct kqid qid);
  81extern bool qid_valid(struct kqid qid);
  82
  83/**
  84 *      make_kqid - Map a user-namespace, type, qid tuple into a kqid.
  85 *      @from: User namespace that the qid is in
  86 *      @type: The type of quota
  87 *      @qid: Quota identifier
  88 *
  89 *      Maps a user-namespace, type qid tuple into a kernel internal
  90 *      kqid, and returns that kqid.
  91 *
  92 *      When there is no mapping defined for the user-namespace, type,
  93 *      qid tuple an invalid kqid is returned.  Callers are expected to
  94 *      test for and handle handle invalid kqids being returned.
  95 *      Invalid kqids may be tested for using qid_valid().
  96 */
  97static inline struct kqid make_kqid(struct user_namespace *from,
  98                                    enum quota_type type, qid_t qid)
  99{
 100        struct kqid kqid;
 101
 102        kqid.type = type;
 103        switch (type) {
 104        case USRQUOTA:
 105                kqid.uid = make_kuid(from, qid);
 106                break;
 107        case GRPQUOTA:
 108                kqid.gid = make_kgid(from, qid);
 109                break;
 110        case PRJQUOTA:
 111                kqid.projid = make_kprojid(from, qid);
 112                break;
 113        default:
 114                BUG();
 115        }
 116        return kqid;
 117}
 118
 119/**
 120 *      make_kqid_invalid - Explicitly make an invalid kqid
 121 *      @type: The type of quota identifier
 122 *
 123 *      Returns an invalid kqid with the specified type.
 124 */
 125static inline struct kqid make_kqid_invalid(enum quota_type type)
 126{
 127        struct kqid kqid;
 128
 129        kqid.type = type;
 130        switch (type) {
 131        case USRQUOTA:
 132                kqid.uid = INVALID_UID;
 133                break;
 134        case GRPQUOTA:
 135                kqid.gid = INVALID_GID;
 136                break;
 137        case PRJQUOTA:
 138                kqid.projid = INVALID_PROJID;
 139                break;
 140        default:
 141                BUG();
 142        }
 143        return kqid;
 144}
 145
 146/**
 147 *      make_kqid_uid - Make a kqid from a kuid
 148 *      @uid: The kuid to make the quota identifier from
 149 */
 150static inline struct kqid make_kqid_uid(kuid_t uid)
 151{
 152        struct kqid kqid;
 153        kqid.type = USRQUOTA;
 154        kqid.uid = uid;
 155        return kqid;
 156}
 157
 158/**
 159 *      make_kqid_gid - Make a kqid from a kgid
 160 *      @gid: The kgid to make the quota identifier from
 161 */
 162static inline struct kqid make_kqid_gid(kgid_t gid)
 163{
 164        struct kqid kqid;
 165        kqid.type = GRPQUOTA;
 166        kqid.gid = gid;
 167        return kqid;
 168}
 169
 170/**
 171 *      make_kqid_projid - Make a kqid from a projid
 172 *      @projid: The kprojid to make the quota identifier from
 173 */
 174static inline struct kqid make_kqid_projid(kprojid_t projid)
 175{
 176        struct kqid kqid;
 177        kqid.type = PRJQUOTA;
 178        kqid.projid = projid;
 179        return kqid;
 180}
 181
 182
 183extern spinlock_t dq_data_lock;
 184
 185/* Maximal numbers of writes for quota operation (insert/delete/update)
 186 * (over VFS all formats) */
 187#define DQUOT_INIT_ALLOC max(V1_INIT_ALLOC, V2_INIT_ALLOC)
 188#define DQUOT_INIT_REWRITE max(V1_INIT_REWRITE, V2_INIT_REWRITE)
 189#define DQUOT_DEL_ALLOC max(V1_DEL_ALLOC, V2_DEL_ALLOC)
 190#define DQUOT_DEL_REWRITE max(V1_DEL_REWRITE, V2_DEL_REWRITE)
 191
 192/*
 193 * Data for one user/group kept in memory
 194 */
 195struct mem_dqblk {
 196        qsize_t dqb_bhardlimit; /* absolute limit on disk blks alloc */
 197        qsize_t dqb_bsoftlimit; /* preferred limit on disk blks */
 198        qsize_t dqb_curspace;   /* current used space */
 199        qsize_t dqb_rsvspace;   /* current reserved space for delalloc*/
 200        qsize_t dqb_ihardlimit; /* absolute limit on allocated inodes */
 201        qsize_t dqb_isoftlimit; /* preferred inode limit */
 202        qsize_t dqb_curinodes;  /* current # allocated inodes */
 203        time_t dqb_btime;       /* time limit for excessive disk use */
 204        time_t dqb_itime;       /* time limit for excessive inode use */
 205};
 206
 207/*
 208 * Data for one quotafile kept in memory
 209 */
 210struct quota_format_type;
 211
 212struct mem_dqinfo {
 213        struct quota_format_type *dqi_format;
 214        int dqi_fmt_id;         /* Id of the dqi_format - used when turning
 215                                 * quotas on after remount RW */
 216        struct list_head dqi_dirty_list;        /* List of dirty dquots */
 217        unsigned long dqi_flags;
 218        unsigned int dqi_bgrace;
 219        unsigned int dqi_igrace;
 220        qsize_t dqi_max_spc_limit;
 221        qsize_t dqi_max_ino_limit;
 222        void *dqi_priv;
 223};
 224
 225struct super_block;
 226
 227/* Mask for flags passed to userspace */
 228#define DQF_GETINFO_MASK (DQF_ROOT_SQUASH | DQF_SYS_FILE)
 229/* Mask for flags modifiable from userspace */
 230#define DQF_SETINFO_MASK DQF_ROOT_SQUASH
 231
 232enum {
 233        DQF_INFO_DIRTY_B = DQF_PRIVATE,
 234};
 235#define DQF_INFO_DIRTY (1 << DQF_INFO_DIRTY_B)  /* Is info dirty? */
 236
 237extern void mark_info_dirty(struct super_block *sb, int type);
 238static inline int info_dirty(struct mem_dqinfo *info)
 239{
 240        return test_bit(DQF_INFO_DIRTY_B, &info->dqi_flags);
 241}
 242
 243enum {
 244        DQST_LOOKUPS,
 245        DQST_DROPS,
 246        DQST_READS,
 247        DQST_WRITES,
 248        DQST_CACHE_HITS,
 249        DQST_ALLOC_DQUOTS,
 250        DQST_FREE_DQUOTS,
 251        DQST_SYNCS,
 252        _DQST_DQSTAT_LAST
 253};
 254
 255struct dqstats {
 256        int stat[_DQST_DQSTAT_LAST];
 257        struct percpu_counter counter[_DQST_DQSTAT_LAST];
 258};
 259
 260extern struct dqstats *dqstats_pcpu;
 261extern struct dqstats dqstats;
 262
 263static inline void dqstats_inc(unsigned int type)
 264{
 265        percpu_counter_inc(&dqstats.counter[type]);
 266}
 267
 268static inline void dqstats_dec(unsigned int type)
 269{
 270        percpu_counter_dec(&dqstats.counter[type]);
 271}
 272
 273#define DQ_MOD_B        0       /* dquot modified since read */
 274#define DQ_BLKS_B       1       /* uid/gid has been warned about blk limit */
 275#define DQ_INODES_B     2       /* uid/gid has been warned about inode limit */
 276#define DQ_FAKE_B       3       /* no limits only usage */
 277#define DQ_READ_B       4       /* dquot was read into memory */
 278#define DQ_ACTIVE_B     5       /* dquot is active (dquot_release not called) */
 279#define DQ_LASTSET_B    6       /* Following 6 bits (see QIF_) are reserved\
 280                                 * for the mask of entries set via SETQUOTA\
 281                                 * quotactl. They are set under dq_data_lock\
 282                                 * and the quota format handling dquot can\
 283                                 * clear them when it sees fit. */
 284
 285struct dquot {
 286        struct hlist_node dq_hash;      /* Hash list in memory */
 287        struct list_head dq_inuse;      /* List of all quotas */
 288        struct list_head dq_free;       /* Free list element */
 289        struct list_head dq_dirty;      /* List of dirty dquots */
 290        struct mutex dq_lock;           /* dquot IO lock */
 291        atomic_t dq_count;              /* Use count */
 292        wait_queue_head_t dq_wait_unused;       /* Wait queue for dquot to become unused */
 293        struct super_block *dq_sb;      /* superblock this applies to */
 294        struct kqid dq_id;              /* ID this applies to (uid, gid, projid) */
 295        loff_t dq_off;                  /* Offset of dquot on disk */
 296        unsigned long dq_flags;         /* See DQ_* */
 297        struct mem_dqblk dq_dqb;        /* Diskquota usage */
 298};
 299
 300/* Operations which must be implemented by each quota format */
 301struct quota_format_ops {
 302        int (*check_quota_file)(struct super_block *sb, int type);      /* Detect whether file is in our format */
 303        int (*read_file_info)(struct super_block *sb, int type);        /* Read main info about file - called on quotaon() */
 304        int (*write_file_info)(struct super_block *sb, int type);       /* Write main info about file */
 305        int (*free_file_info)(struct super_block *sb, int type);        /* Called on quotaoff() */
 306        int (*read_dqblk)(struct dquot *dquot);         /* Read structure for one user */
 307        int (*commit_dqblk)(struct dquot *dquot);       /* Write structure for one user */
 308        int (*release_dqblk)(struct dquot *dquot);      /* Called when last reference to dquot is being dropped */
 309};
 310
 311/* Operations working with dquots */
 312struct dquot_operations {
 313        int (*write_dquot) (struct dquot *);            /* Ordinary dquot write */
 314        struct dquot *(*alloc_dquot)(struct super_block *, int);        /* Allocate memory for new dquot */
 315        void (*destroy_dquot)(struct dquot *);          /* Free memory for dquot */
 316        int (*acquire_dquot) (struct dquot *);          /* Quota is going to be created on disk */
 317        int (*release_dquot) (struct dquot *);          /* Quota is going to be deleted from disk */
 318        int (*mark_dirty) (struct dquot *);             /* Dquot is marked dirty */
 319        int (*write_info) (struct super_block *, int);  /* Write of quota "superblock" */
 320        /* get reserved quota for delayed alloc, value returned is managed by
 321         * quota code only */
 322        qsize_t *(*get_reserved_space) (struct inode *);
 323        int (*get_projid) (struct inode *, kprojid_t *);/* Get project ID */
 324};
 325
 326struct path;
 327
 328/* Structure for communicating via ->get_dqblk() & ->set_dqblk() */
 329struct qc_dqblk {
 330        int d_fieldmask;        /* mask of fields to change in ->set_dqblk() */
 331        u64 d_spc_hardlimit;    /* absolute limit on used space */
 332        u64 d_spc_softlimit;    /* preferred limit on used space */
 333        u64 d_ino_hardlimit;    /* maximum # allocated inodes */
 334        u64 d_ino_softlimit;    /* preferred inode limit */
 335        u64 d_space;            /* Space owned by the user */
 336        u64 d_ino_count;        /* # inodes owned by the user */
 337        s64 d_ino_timer;        /* zero if within inode limits */
 338                                /* if not, we refuse service */
 339        s64 d_spc_timer;        /* similar to above; for space */
 340        int d_ino_warns;        /* # warnings issued wrt num inodes */
 341        int d_spc_warns;        /* # warnings issued wrt used space */
 342        u64 d_rt_spc_hardlimit; /* absolute limit on realtime space */
 343        u64 d_rt_spc_softlimit; /* preferred limit on RT space */
 344        u64 d_rt_space;         /* realtime space owned */
 345        s64 d_rt_spc_timer;     /* similar to above; for RT space */
 346        int d_rt_spc_warns;     /* # warnings issued wrt RT space */
 347};
 348
 349/*
 350 * Field specifiers for ->set_dqblk() in struct qc_dqblk and also for
 351 * ->set_info() in struct qc_info
 352 */
 353#define QC_INO_SOFT     (1<<0)
 354#define QC_INO_HARD     (1<<1)
 355#define QC_SPC_SOFT     (1<<2)
 356#define QC_SPC_HARD     (1<<3)
 357#define QC_RT_SPC_SOFT  (1<<4)
 358#define QC_RT_SPC_HARD  (1<<5)
 359#define QC_LIMIT_MASK (QC_INO_SOFT | QC_INO_HARD | QC_SPC_SOFT | QC_SPC_HARD | \
 360                       QC_RT_SPC_SOFT | QC_RT_SPC_HARD)
 361#define QC_SPC_TIMER    (1<<6)
 362#define QC_INO_TIMER    (1<<7)
 363#define QC_RT_SPC_TIMER (1<<8)
 364#define QC_TIMER_MASK (QC_SPC_TIMER | QC_INO_TIMER | QC_RT_SPC_TIMER)
 365#define QC_SPC_WARNS    (1<<9)
 366#define QC_INO_WARNS    (1<<10)
 367#define QC_RT_SPC_WARNS (1<<11)
 368#define QC_WARNS_MASK (QC_SPC_WARNS | QC_INO_WARNS | QC_RT_SPC_WARNS)
 369#define QC_SPACE        (1<<12)
 370#define QC_INO_COUNT    (1<<13)
 371#define QC_RT_SPACE     (1<<14)
 372#define QC_ACCT_MASK (QC_SPACE | QC_INO_COUNT | QC_RT_SPACE)
 373#define QC_FLAGS        (1<<15)
 374
 375#define QCI_SYSFILE             (1 << 0)        /* Quota file is hidden from userspace */
 376#define QCI_ROOT_SQUASH         (1 << 1)        /* Root squash turned on */
 377#define QCI_ACCT_ENABLED        (1 << 2)        /* Quota accounting enabled */
 378#define QCI_LIMITS_ENFORCED     (1 << 3)        /* Quota limits enforced */
 379
 380/* Structures for communicating via ->get_state */
 381struct qc_type_state {
 382        unsigned int flags;             /* Flags QCI_* */
 383        unsigned int spc_timelimit;     /* Time after which space softlimit is
 384                                         * enforced */
 385        unsigned int ino_timelimit;     /* Ditto for inode softlimit */
 386        unsigned int rt_spc_timelimit;  /* Ditto for real-time space */
 387        unsigned int spc_warnlimit;     /* Limit for number of space warnings */
 388        unsigned int ino_warnlimit;     /* Ditto for inodes */
 389        unsigned int rt_spc_warnlimit;  /* Ditto for real-time space */
 390        unsigned long long ino;         /* Inode number of quota file */
 391        blkcnt_t blocks;                /* Number of 512-byte blocks in the file */
 392        blkcnt_t nextents;              /* Number of extents in the file */
 393};
 394
 395struct qc_state {
 396        unsigned int s_incoredqs;       /* Number of dquots in core */
 397        /*
 398         * Per quota type information. The array should really have
 399         * max(MAXQUOTAS, XQM_MAXQUOTAS) entries. BUILD_BUG_ON in
 400         * quota_getinfo() makes sure XQM_MAXQUOTAS is large enough.  Once VFS
 401         * supports project quotas, this can be changed to MAXQUOTAS
 402         */
 403        struct qc_type_state s_state[XQM_MAXQUOTAS];
 404};
 405
 406/* Structure for communicating via ->set_info */
 407struct qc_info {
 408        int i_fieldmask;        /* mask of fields to change in ->set_info() */
 409        unsigned int i_flags;           /* Flags QCI_* */
 410        unsigned int i_spc_timelimit;   /* Time after which space softlimit is
 411                                         * enforced */
 412        unsigned int i_ino_timelimit;   /* Ditto for inode softlimit */
 413        unsigned int i_rt_spc_timelimit;/* Ditto for real-time space */
 414        unsigned int i_spc_warnlimit;   /* Limit for number of space warnings */
 415        unsigned int i_ino_warnlimit;   /* Limit for number of inode warnings */
 416        unsigned int i_rt_spc_warnlimit;        /* Ditto for real-time space */
 417};
 418
 419/* Operations handling requests from userspace */
 420struct quotactl_ops {
 421        int (*quota_on)(struct super_block *, int, int, struct path *);
 422        int (*quota_off)(struct super_block *, int);
 423        int (*quota_enable)(struct super_block *, unsigned int);
 424        int (*quota_disable)(struct super_block *, unsigned int);
 425        int (*quota_sync)(struct super_block *, int);
 426        int (*set_info)(struct super_block *, int, struct qc_info *);
 427        int (*get_dqblk)(struct super_block *, struct kqid, struct qc_dqblk *);
 428        int (*set_dqblk)(struct super_block *, struct kqid, struct qc_dqblk *);
 429        int (*get_state)(struct super_block *, struct qc_state *);
 430        int (*rm_xquota)(struct super_block *, unsigned int);
 431};
 432
 433struct quota_format_type {
 434        int qf_fmt_id;  /* Quota format id */
 435        const struct quota_format_ops *qf_ops;  /* Operations of format */
 436        struct module *qf_owner;                /* Module implementing quota format */
 437        struct quota_format_type *qf_next;
 438};
 439
 440/**
 441 * Quota state flags - they actually come in two flavors - for users and groups.
 442 *
 443 * Actual typed flags layout:
 444 *                              USRQUOTA        GRPQUOTA
 445 *  DQUOT_USAGE_ENABLED         0x0001          0x0002
 446 *  DQUOT_LIMITS_ENABLED        0x0004          0x0008
 447 *  DQUOT_SUSPENDED             0x0010          0x0020
 448 *
 449 * Following bits are used for non-typed flags:
 450 *  DQUOT_QUOTA_SYS_FILE        0x0040
 451 *  DQUOT_NEGATIVE_USAGE        0x0080
 452 */
 453enum {
 454        _DQUOT_USAGE_ENABLED = 0,               /* Track disk usage for users */
 455        _DQUOT_LIMITS_ENABLED,                  /* Enforce quota limits for users */
 456        _DQUOT_SUSPENDED,                       /* User diskquotas are off, but
 457                                                 * we have necessary info in
 458                                                 * memory to turn them on */
 459        _DQUOT_STATE_FLAGS
 460};
 461#define DQUOT_USAGE_ENABLED     (1 << _DQUOT_USAGE_ENABLED * MAXQUOTAS)
 462#define DQUOT_LIMITS_ENABLED    (1 << _DQUOT_LIMITS_ENABLED * MAXQUOTAS)
 463#define DQUOT_SUSPENDED         (1 << _DQUOT_SUSPENDED * MAXQUOTAS)
 464#define DQUOT_STATE_FLAGS       (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED | \
 465                                 DQUOT_SUSPENDED)
 466/* Other quota flags */
 467#define DQUOT_STATE_LAST        (_DQUOT_STATE_FLAGS * MAXQUOTAS)
 468#define DQUOT_QUOTA_SYS_FILE    (1 << DQUOT_STATE_LAST)
 469                                                /* Quota file is a special
 470                                                 * system file and user cannot
 471                                                 * touch it. Filesystem is
 472                                                 * responsible for setting
 473                                                 * S_NOQUOTA, S_NOATIME flags
 474                                                 */
 475#define DQUOT_NEGATIVE_USAGE    (1 << (DQUOT_STATE_LAST + 1))
 476                                               /* Allow negative quota usage */
 477static inline unsigned int dquot_state_flag(unsigned int flags, int type)
 478{
 479        return flags << type;
 480}
 481
 482static inline unsigned int dquot_generic_flag(unsigned int flags, int type)
 483{
 484        return (flags >> type) & DQUOT_STATE_FLAGS;
 485}
 486
 487/* Bitmap of quota types where flag is set in flags */
 488static __always_inline unsigned dquot_state_types(unsigned flags, unsigned flag)
 489{
 490        BUILD_BUG_ON_NOT_POWER_OF_2(flag);
 491        return (flags / flag) & ((1 << MAXQUOTAS) - 1);
 492}
 493
 494#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
 495extern void quota_send_warning(struct kqid qid, dev_t dev,
 496                               const char warntype);
 497#else
 498static inline void quota_send_warning(struct kqid qid, dev_t dev,
 499                                      const char warntype)
 500{
 501        return;
 502}
 503#endif /* CONFIG_QUOTA_NETLINK_INTERFACE */
 504
 505struct quota_info {
 506        unsigned int flags;                     /* Flags for diskquotas on this device */
 507        struct mutex dqio_mutex;                /* lock device while I/O in progress */
 508        struct mutex dqonoff_mutex;             /* Serialize quotaon & quotaoff */
 509        struct inode *files[MAXQUOTAS];         /* inodes of quotafiles */
 510        struct mem_dqinfo info[MAXQUOTAS];      /* Information for each quota type */
 511        const struct quota_format_ops *ops[MAXQUOTAS];  /* Operations for each type */
 512};
 513
 514int register_quota_format(struct quota_format_type *fmt);
 515void unregister_quota_format(struct quota_format_type *fmt);
 516
 517struct quota_module_name {
 518        int qm_fmt_id;
 519        char *qm_mod_name;
 520};
 521
 522#define INIT_QUOTA_MODULE_NAMES {\
 523        {QFMT_VFS_OLD, "quota_v1"},\
 524        {QFMT_VFS_V0, "quota_v2"},\
 525        {QFMT_VFS_V1, "quota_v2"},\
 526        {0, NULL}}
 527
 528#endif /* _QUOTA_ */
 529