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  */
  88 enum {
  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
 108 struct 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
 129 struct 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
 151 enum {
 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
 158 enum {
 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
 185 typedef __kernel_uid32_t qid_t; /* Type in which we store ids in memory */
 186 typedef long long qsize_t;      /* Type in which we store sizes */
 187
 188 extern 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  */
 200 struct 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  */
 215 struct quota_format_type;
 216
 217 struct 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
 230 struct 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
 240 extern void mark_info_dirty(struct super_block *sb, int type);
 241 static inline int info_dirty(struct mem_dqinfo *info)
 242 {
 243         return test_bit(DQF_INFO_DIRTY_B, &info->dqi_flags);
 244 }
 245
 246 enum {
 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
 258 struct dqstats {
 259         int stat[_DQST_DQSTAT_LAST];
 260         struct percpu_counter counter[_DQST_DQSTAT_LAST];
 261 };
 262
 263 extern struct dqstats *dqstats_pcpu;
 264 extern struct dqstats dqstats;
 265
 266 static inline void dqstats_inc(unsigned int type)
 267 {
 268         percpu_counter_inc(&dqstats.counter[type]);
 269 }
 270
 271 static 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
 288 struct 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 */
 305 struct 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 */
 316 struct 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
 329 struct path;
 330
 331 /* Operations handling requests from userspace */
 332 struct 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
 345 struct 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 */
 353 enum {
 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
 378 static inline unsigned int dquot_state_flag(unsigned int flags, int type)
 379 {
 380         return flags << _DQUOT_STATE_FLAGS * type;
 381 }
 382
 383 static 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
 389 extern void quota_send_warning(short type, unsigned int id, dev_t dev,
 390                                const char warntype);
 391 #else
 392 static 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
 399 struct 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
 409 int register_quota_format(struct quota_format_type *fmt);
 410 void unregister_quota_format(struct quota_format_type *fmt);
 411
 412 struct 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_ */