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
  33#ifndef _LINUX_QUOTA_
  34#define _LINUX_QUOTA_
  35
  36#include <linux/errno.h>
  37#include <linux/types.h>
  38
  39#define __DQUOT_VERSION__       "dquot_6.5.2"
  40
  41#define MAXQUOTAS 2
  42#define USRQUOTA  0             /* element used for user quotas */
  43#define GRPQUOTA  1             /* element used for group quotas */
  44
  45/*
  46 * Definitions for the default names of the quotas files.
  47 */
  48#define INITQFNAMES { \
  49        "user",    /* USRQUOTA */ \
  50        "group",   /* GRPQUOTA */ \
  51        "undefined", \
  52};
  53
  54/*
  55 * Command definitions for the 'quotactl' system call.
  56 * The commands are broken into a main command defined below
  57 * and a subcommand that is used to convey the type of
  58 * quota that is being manipulated (see above).
  59 */
  60#define SUBCMDMASK  0x00ff
  61#define SUBCMDSHIFT 8
  62#define QCMD(cmd, type)  (((cmd) << SUBCMDSHIFT) | ((type) & SUBCMDMASK))
  63
  64#define Q_SYNC     0x800001     /* sync disk copy of a filesystems quotas */
  65#define Q_QUOTAON  0x800002     /* turn quotas on */
  66#define Q_QUOTAOFF 0x800003     /* turn quotas off */
  67#define Q_GETFMT   0x800004     /* get quota format used on given filesystem */
  68#define Q_GETINFO  0x800005     /* get information about quota files */
  69#define Q_SETINFO  0x800006     /* set information about quota files */
  70#define Q_GETQUOTA 0x800007     /* get user quota structure */
  71#define Q_SETQUOTA 0x800008     /* set user quota structure */
  72
  73/* Quota format type IDs */
  74#define QFMT_VFS_OLD 1
  75#define QFMT_VFS_V0 2
  76#define QFMT_OCFS2 3
  77#define QFMT_VFS_V1 4
  78
  79/* Size of block in which space limits are passed through the quota
  80 * interface */
  81#define QIF_DQBLKSIZE_BITS 10
  82#define QIF_DQBLKSIZE (1 << QIF_DQBLKSIZE_BITS)
  83
  84/*
  85 * Quota structure used for communication with userspace via quotactl
  86 * Following flags are used to specify which fields are valid
  87 */
  88enum {
  89        QIF_BLIMITS_B = 0,
  90        QIF_SPACE_B,
  91        QIF_ILIMITS_B,
  92        QIF_INODES_B,
  93        QIF_BTIME_B,
  94        QIF_ITIME_B,
  95};
  96
  97#define QIF_BLIMITS     (1 << QIF_BLIMITS_B)
  98#define QIF_SPACE       (1 << QIF_SPACE_B)
  99#define QIF_ILIMITS     (1 << QIF_ILIMITS_B)
 100#define QIF_INODES      (1 << QIF_INODES_B)
 101#define QIF_BTIME       (1 << QIF_BTIME_B)
 102#define QIF_ITIME       (1 << QIF_ITIME_B)
 103#define QIF_LIMITS      (QIF_BLIMITS | QIF_ILIMITS)
 104#define QIF_USAGE       (QIF_SPACE | QIF_INODES)
 105#define QIF_TIMES       (QIF_BTIME | QIF_ITIME)
 106#define QIF_ALL         (QIF_LIMITS | QIF_USAGE | QIF_TIMES)
 107
 108struct if_dqblk {
 109        __u64 dqb_bhardlimit;
 110        __u64 dqb_bsoftlimit;
 111        __u64 dqb_curspace;
 112        __u64 dqb_ihardlimit;
 113        __u64 dqb_isoftlimit;
 114        __u64 dqb_curinodes;
 115        __u64 dqb_btime;
 116        __u64 dqb_itime;
 117        __u32 dqb_valid;
 118};
 119
 120/*
 121 * Structure used for setting quota information about file via quotactl
 122 * Following flags are used to specify which fields are valid
 123 */
 124#define IIF_BGRACE      1
 125#define IIF_IGRACE      2
 126#define IIF_FLAGS       4
 127#define IIF_ALL         (IIF_BGRACE | IIF_IGRACE | IIF_FLAGS)
 128
 129struct if_dqinfo {
 130        __u64 dqi_bgrace;
 131        __u64 dqi_igrace;
 132        __u32 dqi_flags;
 133        __u32 dqi_valid;
 134};
 135
 136/*
 137 * Definitions for quota netlink interface
 138 */
 139#define QUOTA_NL_NOWARN 0
 140#define QUOTA_NL_IHARDWARN 1            /* Inode hardlimit reached */
 141#define QUOTA_NL_ISOFTLONGWARN 2        /* Inode grace time expired */
 142#define QUOTA_NL_ISOFTWARN 3            /* Inode softlimit reached */
 143#define QUOTA_NL_BHARDWARN 4            /* Block hardlimit reached */
 144#define QUOTA_NL_BSOFTLONGWARN 5        /* Block grace time expired */
 145#define QUOTA_NL_BSOFTWARN 6            /* Block softlimit reached */
 146#define QUOTA_NL_IHARDBELOW 7           /* Usage got below inode hardlimit */
 147#define QUOTA_NL_ISOFTBELOW 8           /* Usage got below inode softlimit */
 148#define QUOTA_NL_BHARDBELOW 9           /* Usage got below block hardlimit */
 149#define QUOTA_NL_BSOFTBELOW 10          /* Usage got below block softlimit */
 150
 151enum {
 152        QUOTA_NL_C_UNSPEC,
 153        QUOTA_NL_C_WARNING,
 154        __QUOTA_NL_C_MAX,
 155};
 156#define QUOTA_NL_C_MAX (__QUOTA_NL_C_MAX - 1)
 157
 158enum {
 159        QUOTA_NL_A_UNSPEC,
 160        QUOTA_NL_A_QTYPE,
 161        QUOTA_NL_A_EXCESS_ID,
 162        QUOTA_NL_A_WARNING,
 163        QUOTA_NL_A_DEV_MAJOR,
 164        QUOTA_NL_A_DEV_MINOR,
 165        QUOTA_NL_A_CAUSED_ID,
 166        __QUOTA_NL_A_MAX,
 167};
 168#define QUOTA_NL_A_MAX (__QUOTA_NL_A_MAX - 1)
 169
 170
 171#ifdef __KERNEL__
 172#include <linux/list.h>
 173#include <linux/mutex.h>
 174#include <linux/rwsem.h>
 175#include <linux/spinlock.h>
 176#include <linux/wait.h>
 177#include <linux/percpu_counter.h>
 178
 179#include <linux/dqblk_xfs.h>
 180#include <linux/dqblk_v1.h>
 181#include <linux/dqblk_v2.h>
 182
 183#include <linux/atomic.h>
 184
 185typedef __kernel_uid32_t qid_t; /* Type in which we store ids in memory */
 186typedef long long qsize_t;      /* Type in which we store sizes */
 187
 188extern spinlock_t dq_data_lock;
 189
 190/* Maximal numbers of writes for quota operation (insert/delete/update)
 191 * (over VFS all formats) */
 192#define DQUOT_INIT_ALLOC max(V1_INIT_ALLOC, V2_INIT_ALLOC)
 193#define DQUOT_INIT_REWRITE max(V1_INIT_REWRITE, V2_INIT_REWRITE)
 194#define DQUOT_DEL_ALLOC max(V1_DEL_ALLOC, V2_DEL_ALLOC)
 195#define DQUOT_DEL_REWRITE max(V1_DEL_REWRITE, V2_DEL_REWRITE)
 196
 197/*
 198 * Data for one user/group kept in memory
 199 */
 200struct mem_dqblk {
 201        qsize_t dqb_bhardlimit; /* absolute limit on disk blks alloc */
 202        qsize_t dqb_bsoftlimit; /* preferred limit on disk blks */
 203        qsize_t dqb_curspace;   /* current used space */
 204        qsize_t dqb_rsvspace;   /* current reserved space for delalloc*/
 205        qsize_t dqb_ihardlimit; /* absolute limit on allocated inodes */
 206        qsize_t dqb_isoftlimit; /* preferred inode limit */
 207        qsize_t dqb_curinodes;  /* current # allocated inodes */
 208        time_t dqb_btime;       /* time limit for excessive disk use */
 209        time_t dqb_itime;       /* time limit for excessive inode use */
 210};
 211
 212/*
 213 * Data for one quotafile kept in memory
 214 */
 215struct quota_format_type;
 216
 217struct mem_dqinfo {
 218        struct quota_format_type *dqi_format;
 219        int dqi_fmt_id;         /* Id of the dqi_format - used when turning
 220                                 * quotas on after remount RW */
 221        struct list_head dqi_dirty_list;        /* List of dirty dquots */
 222        unsigned long dqi_flags;
 223        unsigned int dqi_bgrace;
 224        unsigned int dqi_igrace;
 225        qsize_t dqi_maxblimit;
 226        qsize_t dqi_maxilimit;
 227        void *dqi_priv;
 228};
 229
 230struct super_block;
 231
 232#define DQF_MASK 0xffff         /* Mask for format specific flags */
 233#define DQF_GETINFO_MASK 0x1ffff        /* Mask for flags passed to userspace */
 234#define DQF_SETINFO_MASK 0xffff         /* Mask for flags modifiable from userspace */
 235#define DQF_SYS_FILE_B          16
 236#define DQF_SYS_FILE (1 << DQF_SYS_FILE_B)      /* Quota file stored as system file */
 237#define DQF_INFO_DIRTY_B        31
 238#define DQF_INFO_DIRTY (1 << DQF_INFO_DIRTY_B)  /* Is info dirty? */
 239
 240extern void mark_info_dirty(struct super_block *sb, int type);
 241static inline int info_dirty(struct mem_dqinfo *info)
 242{
 243        return test_bit(DQF_INFO_DIRTY_B, &info->dqi_flags);
 244}
 245
 246enum {
 247        DQST_LOOKUPS,
 248        DQST_DROPS,
 249        DQST_READS,
 250        DQST_WRITES,
 251        DQST_CACHE_HITS,
 252        DQST_ALLOC_DQUOTS,
 253        DQST_FREE_DQUOTS,
 254        DQST_SYNCS,
 255        _DQST_DQSTAT_LAST
 256};
 257
 258struct dqstats {
 259        int stat[_DQST_DQSTAT_LAST];
 260        struct percpu_counter counter[_DQST_DQSTAT_LAST];
 261};
 262
 263extern struct dqstats *dqstats_pcpu;
 264extern struct dqstats dqstats;
 265
 266static inline void dqstats_inc(unsigned int type)
 267{
 268        percpu_counter_inc(&dqstats.counter[type]);
 269}
 270
 271static inline void dqstats_dec(unsigned int type)
 272{
 273        percpu_counter_dec(&dqstats.counter[type]);
 274}
 275
 276#define DQ_MOD_B        0       /* dquot modified since read */
 277#define DQ_BLKS_B       1       /* uid/gid has been warned about blk limit */
 278#define DQ_INODES_B     2       /* uid/gid has been warned about inode limit */
 279#define DQ_FAKE_B       3       /* no limits only usage */
 280#define DQ_READ_B       4       /* dquot was read into memory */
 281#define DQ_ACTIVE_B     5       /* dquot is active (dquot_release not called) */
 282#define DQ_LASTSET_B    6       /* Following 6 bits (see QIF_) are reserved\
 283                                 * for the mask of entries set via SETQUOTA\
 284                                 * quotactl. They are set under dq_data_lock\
 285                                 * and the quota format handling dquot can\
 286                                 * clear them when it sees fit. */
 287
 288struct dquot {
 289        struct hlist_node dq_hash;      /* Hash list in memory */
 290        struct list_head dq_inuse;      /* List of all quotas */
 291        struct list_head dq_free;       /* Free list element */
 292        struct list_head dq_dirty;      /* List of dirty dquots */
 293        struct mutex dq_lock;           /* dquot IO lock */
 294        atomic_t dq_count;              /* Use count */
 295        wait_queue_head_t dq_wait_unused;       /* Wait queue for dquot to become unused */
 296        struct super_block *dq_sb;      /* superblock this applies to */
 297        unsigned int dq_id;             /* ID this applies to (uid, gid) */
 298        loff_t dq_off;                  /* Offset of dquot on disk */
 299        unsigned long dq_flags;         /* See DQ_* */
 300        short dq_type;                  /* Type of quota */
 301        struct mem_dqblk dq_dqb;        /* Diskquota usage */
 302};
 303
 304/* Operations which must be implemented by each quota format */
 305struct quota_format_ops {
 306        int (*check_quota_file)(struct super_block *sb, int type);      /* Detect whether file is in our format */
 307        int (*read_file_info)(struct super_block *sb, int type);        /* Read main info about file - called on quotaon() */
 308        int (*write_file_info)(struct super_block *sb, int type);       /* Write main info about file */
 309        int (*free_file_info)(struct super_block *sb, int type);        /* Called on quotaoff() */
 310        int (*read_dqblk)(struct dquot *dquot);         /* Read structure for one user */
 311        int (*commit_dqblk)(struct dquot *dquot);       /* Write structure for one user */
 312        int (*release_dqblk)(struct dquot *dquot);      /* Called when last reference to dquot is being dropped */
 313};
 314
 315/* Operations working with dquots */
 316struct dquot_operations {
 317        int (*write_dquot) (struct dquot *);            /* Ordinary dquot write */
 318        struct dquot *(*alloc_dquot)(struct super_block *, int);        /* Allocate memory for new dquot */
 319        void (*destroy_dquot)(struct dquot *);          /* Free memory for dquot */
 320        int (*acquire_dquot) (struct dquot *);          /* Quota is going to be created on disk */
 321        int (*release_dquot) (struct dquot *);          /* Quota is going to be deleted from disk */
 322        int (*mark_dirty) (struct dquot *);             /* Dquot is marked dirty */
 323        int (*write_info) (struct super_block *, int);  /* Write of quota "superblock" */
 324        /* get reserved quota for delayed alloc, value returned is managed by
 325         * quota code only */
 326        qsize_t *(*get_reserved_space) (struct inode *);
 327};
 328
 329struct path;
 330
 331/* Operations handling requests from userspace */
 332struct quotactl_ops {
 333        int (*quota_on)(struct super_block *, int, int, struct path *);
 334        int (*quota_on_meta)(struct super_block *, int, int);
 335        int (*quota_off)(struct super_block *, int);
 336        int (*quota_sync)(struct super_block *, int, int);
 337        int (*get_info)(struct super_block *, int, struct if_dqinfo *);
 338        int (*set_info)(struct super_block *, int, struct if_dqinfo *);
 339        int (*get_dqblk)(struct super_block *, int, qid_t, struct fs_disk_quota *);
 340        int (*set_dqblk)(struct super_block *, int, qid_t, struct fs_disk_quota *);
 341        int (*get_xstate)(struct super_block *, struct fs_quota_stat *);
 342        int (*set_xstate)(struct super_block *, unsigned int, int);
 343};
 344
 345struct quota_format_type {
 346        int qf_fmt_id;  /* Quota format id */
 347        const struct quota_format_ops *qf_ops;  /* Operations of format */
 348        struct module *qf_owner;                /* Module implementing quota format */
 349        struct quota_format_type *qf_next;
 350};
 351
 352/* Quota state flags - they actually come in two flavors - for users and groups */
 353enum {
 354        _DQUOT_USAGE_ENABLED = 0,               /* Track disk usage for users */
 355        _DQUOT_LIMITS_ENABLED,                  /* Enforce quota limits for users */
 356        _DQUOT_SUSPENDED,                       /* User diskquotas are off, but
 357                                                 * we have necessary info in
 358                                                 * memory to turn them on */
 359        _DQUOT_STATE_FLAGS
 360};
 361#define DQUOT_USAGE_ENABLED     (1 << _DQUOT_USAGE_ENABLED)
 362#define DQUOT_LIMITS_ENABLED    (1 << _DQUOT_LIMITS_ENABLED)
 363#define DQUOT_SUSPENDED         (1 << _DQUOT_SUSPENDED)
 364#define DQUOT_STATE_FLAGS       (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED | \
 365                                 DQUOT_SUSPENDED)
 366/* Other quota flags */
 367#define DQUOT_STATE_LAST        (_DQUOT_STATE_FLAGS * MAXQUOTAS)
 368#define DQUOT_QUOTA_SYS_FILE    (1 << DQUOT_STATE_LAST)
 369                                                /* Quota file is a special
 370                                                 * system file and user cannot
 371                                                 * touch it. Filesystem is
 372                                                 * responsible for setting
 373                                                 * S_NOQUOTA, S_NOATIME flags
 374                                                 */
 375#define DQUOT_NEGATIVE_USAGE    (1 << (DQUOT_STATE_LAST + 1))
 376                                               /* Allow negative quota usage */
 377
 378static inline unsigned int dquot_state_flag(unsigned int flags, int type)
 379{
 380        return flags << _DQUOT_STATE_FLAGS * type;
 381}
 382
 383static inline unsigned int dquot_generic_flag(unsigned int flags, int type)
 384{
 385        return (flags >> _DQUOT_STATE_FLAGS * type) & DQUOT_STATE_FLAGS;
 386}
 387
 388#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
 389extern void quota_send_warning(short type, unsigned int id, dev_t dev,
 390                               const char warntype);
 391#else
 392static inline void quota_send_warning(short type, unsigned int id, dev_t dev,
 393                                      const char warntype)
 394{
 395        return;
 396}
 397#endif /* CONFIG_QUOTA_NETLINK_INTERFACE */
 398
 399struct quota_info {
 400        unsigned int flags;                     /* Flags for diskquotas on this device */
 401        struct mutex dqio_mutex;                /* lock device while I/O in progress */
 402        struct mutex dqonoff_mutex;             /* Serialize quotaon & quotaoff */
 403        struct rw_semaphore dqptr_sem;          /* serialize ops using quota_info struct, pointers from inode to dquots */
 404        struct inode *files[MAXQUOTAS];         /* inodes of quotafiles */
 405        struct mem_dqinfo info[MAXQUOTAS];      /* Information for each quota type */
 406        const struct quota_format_ops *ops[MAXQUOTAS];  /* Operations for each type */
 407};
 408
 409int register_quota_format(struct quota_format_type *fmt);
 410void unregister_quota_format(struct quota_format_type *fmt);
 411
 412struct quota_module_name {
 413        int qm_fmt_id;
 414        char *qm_mod_name;
 415};
 416
 417#define INIT_QUOTA_MODULE_NAMES {\
 418        {QFMT_VFS_OLD, "quota_v1"},\
 419        {QFMT_VFS_V0, "quota_v2"},\
 420        {0, NULL}}
 421
 422#endif /* __KERNEL__ */
 423#endif /* _QUOTA_ */
 424