bsd/sys/quota.h

   1 /*
   2  * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * Copyright (c) 1982, 1986, 1993
  27  *      The Regents of the University of California.  All rights reserved.
  28  *
  29  * This code is derived from software contributed to Berkeley by
  30  * Robert Elz at The University of Melbourne.
  31  *
  32  * Redistribution and use in source and binary forms, with or without
  33  * modification, are permitted provided that the following conditions
  34  * are met:
  35  * 1. Redistributions of source code must retain the above copyright
  36  *    notice, this list of conditions and the following disclaimer.
  37  * 2. Redistributions in binary form must reproduce the above copyright
  38  *    notice, this list of conditions and the following disclaimer in the
  39  *    documentation and/or other materials provided with the distribution.
  40  * 3. All advertising materials mentioning features or use of this software
  41  *    must display the following acknowledgement:
  42  *      This product includes software developed by the University of
  43  *      California, Berkeley and its contributors.
  44  * 4. Neither the name of the University nor the names of its contributors
  45  *    may be used to endorse or promote products derived from this software
  46  *    without specific prior written permission.
  47  *
  48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  58  * SUCH DAMAGE.
  59  *
  60  *      @(#)quota.h
  61  *      derived from @(#)ufs/ufs/quota.h        8.3 (Berkeley) 8/19/94
  62  */
  63
  64 #ifndef _SYS_QUOTA_H
  65 #define _SYS_QUOTA_H
  66
  67 #include <sys/appleapiopts.h>
  68
  69 #ifdef __APPLE_API_UNSTABLE
  70 /*
  71  * Definitions for disk quotas imposed on the average user
  72  * (big brother finally hits UNIX).
  73  *
  74  * The following constants define the amount of time given a user before the
  75  * soft limits are treated as hard limits (usually resulting in an allocation
  76  * failure). The timer is started when the user crosses their soft limit, it
  77  * is reset when they go below their soft limit.
  78  */
  79 #define MAX_IQ_TIME     (7*24*60*60)    /* seconds in 1 week */
  80 #define MAX_DQ_TIME     (7*24*60*60)    /* seconds in 1 week */
  81
  82 /*
  83  * The following constants define the usage of the quota file array in the
  84  * file system mount structure and dquot array in the inode structure.  The semantics
  85  * of the elements of these arrays are defined in the routine getinoquota;
  86  * the remainder of the quota code treats them generically and need not be
  87  * inspected when changing the size of the array.
  88  */
  89 #define MAXQUOTAS       2
  90 #define USRQUOTA        0       /* element used for user quotas */
  91 #define GRPQUOTA        1       /* element used for group quotas */
  92
  93 /*
  94  * Definitions for the default names of the quotas files.
  95  */
  96 #define INITQFNAMES { \
  97         "user",         /* USRQUOTA */ \
  98         "group",        /* GRPQUOTA */ \
  99         "undefined", \
 100 };
 101 #define QUOTAFILENAME   ".quota"
 102 #define QUOTAOPSNAME    ".quota.ops"
 103 #define QUOTAGROUP      "operator"
 104
 105 /*
 106  * Command definitions for the 'quotactl' system call.  The commands are
 107  * broken into a main command defined below and a subcommand that is used
 108  * to convey the type of quota that is being manipulated (see above).
 109  */
 110 #define SUBCMDMASK      0x00ff
 111 #define SUBCMDSHIFT     8
 112 #define QCMD(cmd, type) (((cmd) << SUBCMDSHIFT) | ((type) & SUBCMDMASK))
 113
 114 #define Q_QUOTAON       0x0100  /* enable quotas */
 115 #define Q_QUOTAOFF      0x0200  /* disable quotas */
 116 #define Q_GETQUOTA      0x0300  /* get limits and usage */
 117 #define Q_SETQUOTA      0x0400  /* set limits and usage */
 118 #define Q_SETUSE        0x0500  /* set usage */
 119 #define Q_SYNC          0x0600  /* sync disk copy of a filesystems quotas */
 120 #define Q_QUOTASTAT     0x0700  /* get quota on/off status */
 121
 122 /*
 123  * The following two structures define the format of the disk
 124  * quota file (as it appears on disk) - the file contains a
 125  * header followed by a hash table of dqblk entries.  To find
 126  * a particular entry, the user or group number (id) is first
 127  * converted to an index into this table by means of the hash
 128  * function dqhash1.  If there is a collision at that index
 129  * location then a second hash value is computed which using
 130  * dqhash2.  This second hash value is then used as an offset
 131  * to the next location to probe.  ID = 0 is used to indicate
 132  * an empty (unused) entry.  So there can never be an entry in
 133  * the quota file for user 0 or group 0 (which is OK since disk
 134  * quotas are never enforced for user 0).
 135  *
 136  * The setquota system call establishes the vnode for each quota
 137  * file (a pointer is retained in the filesystem  mount structure).
 138  */
 139 struct dqfilehdr {
 140         u_int32_t dqh_magic;
 141         u_int32_t dqh_version;          /* == QF_VERSION */
 142         u_int32_t dqh_maxentries;       /* must be a power of 2 */
 143         u_int32_t dqh_entrycnt;         /* count of active entries */
 144         u_int32_t dqh_flags;            /* reserved for now (0) */
 145         time_t    dqh_chktime;          /* time of last quota check */
 146         time_t    dqh_btime;            /* time limit for excessive disk use */
 147         time_t    dqh_itime;            /* time limit for excessive files */
 148         char      dqh_string[16];       /* tag string */
 149         u_int32_t dqh_spare[4];         /* pad struct to power of 2 */
 150 };
 151
 152 struct dqblk {
 153         u_int64_t dqb_bhardlimit;       /* absolute limit on disk bytes alloc */
 154         u_int64_t dqb_bsoftlimit;       /* preferred limit on disk bytes */
 155         u_int64_t dqb_curbytes;         /* current byte count */
 156         u_int32_t dqb_ihardlimit;       /* maximum # allocated inodes + 1 */
 157         u_int32_t dqb_isoftlimit;       /* preferred inode limit */
 158         u_int32_t dqb_curinodes;        /* current # allocated inodes */
 159         time_t    dqb_btime;            /* time limit for excessive disk use */
 160         time_t    dqb_itime;            /* time limit for excessive files */
 161         u_int32_t dqb_id;               /* identifier (0 for empty entries) */
 162         u_int32_t dqb_spare[4];         /* pad struct to power of 2 */
 163 };
 164
 165
 166 #define INITQMAGICS { \
 167         0xff31ff35,     /* USRQUOTA */ \
 168         0xff31ff27,     /* GRPQUOTA */ \
 169 };
 170
 171 #define QF_VERSION          1
 172 #define QF_STRING_TAG       "QUOTA HASH FILE"
 173
 174 #define QF_USERS_PER_GB     256
 175 #define QF_MIN_USERS        2048
 176 #define QF_MAX_USERS       (2048*1024)
 177
 178 #define QF_GROUPS_PER_GB    32
 179 #define QF_MIN_GROUPS       2048
 180 #define QF_MAX_GROUPS       (256*1024)
 181
 182
 183 /*
 184  * The primary and secondary multiplicative hash functions are
 185  * derived from Knuth (vol. 3). They use a prime that is in
 186  * golden ratio to the machine's word size.
 187  */
 188 #define dqhash1(id, shift, mask)  \
 189         ((((id) * 2654435761UL) >> (shift)) & (mask))
 190
 191 #define dqhash2(id, mask)  \
 192         (dqhash1((id), 11, (mask)>>1) | 1)
 193
 194 /*
 195  * Compute a disk offset into a quota file.
 196  */
 197 #define dqoffset(index)  \
 198         (sizeof (struct dqfilehdr) + ((index) * sizeof (struct dqblk)))
 199 /*
 200  * Compute the hash shift value.
 201  * It is the word size, in bits, minus the hash table size, in bits.
 202  */
 203 static __inline int dqhashshift(u_long);
 204
 205 static __inline int
 206 dqhashshift(u_long size)
 207 {
 208         int shift;
 209
 210         for (shift = 32; size > 1; size >>= 1, --shift)
 211                 continue;
 212         return (shift);
 213 }
 214
 215
 216 #ifndef KERNEL
 217
 218 #include <sys/cdefs.h>
 219
 220 __BEGIN_DECLS
 221 int quotactl __P((char *, int, int, caddr_t));
 222 __END_DECLS
 223 #endif /* !KERNEL */
 224
 225 #ifdef KERNEL
 226 #include <sys/queue.h>
 227
 228 /*
 229  * Macros to avoid subroutine calls to trivial functions.
 230  */
 231 #if DIAGNOSTIC
 232 #define DQREF(dq)       dqref(dq)
 233 #else
 234 #define DQREF(dq)       (dq)->dq_cnt++
 235 #endif
 236
 237
 238 /* Quota file info
 239  */
 240 struct quotafile {
 241         struct vnode *qf_vp;         /* quota file vnode */
 242         struct ucred *qf_cred;       /* quota file access cred */
 243         int           qf_shift;      /* primary hash shift */
 244         int           qf_maxentries; /* size of hash table (power of 2) */
 245         int           qf_entrycnt;  /* count of active entries */
 246         time_t        qf_btime;      /* block quota time limit */
 247         time_t        qf_itime;      /* inode quota time limit */
 248         char          qf_qflags;     /* quota specific flags */
 249 };
 250
 251 /*
 252  * Flags describing the runtime state of quotas.
 253  * (in qf_qflags)
 254  */
 255 #define QTF_OPENING     0x01    /* Q_QUOTAON in progress */
 256 #define QTF_CLOSING     0x02    /* Q_QUOTAOFF in progress */
 257
 258
 259 /*
 260  * The following structure records disk usage for a user or group on a
 261  * filesystem. There is one allocated for each quota that exists on any
 262  * filesystem for the current user or group. A cache is kept of recently
 263  * used entries.
 264  */
 265 struct dquot {
 266         LIST_ENTRY(dquot) dq_hash;      /* hash list */
 267         TAILQ_ENTRY(dquot) dq_freelist; /* free list */
 268         u_int16_t dq_flags;             /* flags, see below */
 269         u_int16_t dq_cnt;               /* count of active references */
 270         u_int16_t dq_spare;             /* unused spare padding */
 271         u_int16_t dq_type;              /* quota type of this dquot */
 272         u_int32_t dq_id;                /* identifier this applies to */
 273         u_int32_t dq_index;             /* index into quota file */
 274         struct  quotafile *dq_qfile;    /* quota file that this is taken from */
 275         struct  dqblk dq_dqb;           /* actual usage & quotas */
 276 };
 277 /*
 278  * Flag values.
 279  */
 280 #define DQ_LOCK         0x01            /* this quota locked (no MODS) */
 281 #define DQ_WANT         0x02            /* wakeup on unlock */
 282 #define DQ_MOD          0x04            /* this quota modified since read */
 283 #define DQ_FAKE         0x08            /* no limits here, just usage */
 284 #define DQ_BLKS         0x10            /* has been warned about blk limit */
 285 #define DQ_INODS        0x20            /* has been warned about inode limit */
 286 /*
 287  * Shorthand notation.
 288  */
 289 #define dq_bhardlimit   dq_dqb.dqb_bhardlimit
 290 #define dq_bsoftlimit   dq_dqb.dqb_bsoftlimit
 291 #define dq_curbytes     dq_dqb.dqb_curbytes
 292 #define dq_ihardlimit   dq_dqb.dqb_ihardlimit
 293 #define dq_isoftlimit   dq_dqb.dqb_isoftlimit
 294 #define dq_curinodes    dq_dqb.dqb_curinodes
 295 #define dq_btime        dq_dqb.dqb_btime
 296 #define dq_itime        dq_dqb.dqb_itime
 297
 298 /*
 299  * If the system has never checked for a quota for this file, then it is
 300  * set to NODQUOT.  Once a write attempt is made the inode pointer is set
 301  * to reference a dquot structure.
 302  */
 303 #define NODQUOT         NULL
 304
 305 /*
 306  * Flags to chkdq() and chkiq()
 307  */
 308 #define FORCE   0x01    /* force usage changes independent of limits */
 309 #define CHOWN   0x02    /* (advisory) change initiated by chown */
 310
 311
 312 /*
 313  * Functions that manage the in-core dquot and the
 314  * on-disk dqblk data structures.
 315  */
 316 __BEGIN_DECLS
 317 int     dqfileopen(struct quotafile *, int);
 318 void    dqfileclose(struct quotafile *, int);
 319 void    dqflush(struct vnode *);
 320 int     dqget(struct vnode *, u_long, struct quotafile *, int, struct dquot **);
 321 void    dqinit(void);
 322 void    dqref(struct dquot *);
 323 void    dqrele(struct vnode *, struct dquot *);
 324 void    dqreclaim(struct vnode *, struct dquot *);
 325 int     dqsync(struct vnode *, struct dquot *);
 326 void    dqsync_orphans(struct quotafile *);
 327 __END_DECLS
 328
 329 #endif /* KERNEL */
 330
 331 #endif /* __APPLE_API_UNSTABLE */
 332
 333 #endif /* !_SYS_QUOTA_H_ */