bsd/sys/quota.h

   1 /*
   2  * Copyright (c) 2006 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License.  The rights granted to you under the
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 /*
  31  * Copyright (c) 1982, 1986, 1993
  32  *      The Regents of the University of California.  All rights reserved.
  33  *
  34  * This code is derived from software contributed to Berkeley by
  35  * Robert Elz at The University of Melbourne.
  36  *
  37  * Redistribution and use in source and binary forms, with or without
  38  * modification, are permitted provided that the following conditions
  39  * are met:
  40  * 1. Redistributions of source code must retain the above copyright
  41  *    notice, this list of conditions and the following disclaimer.
  42  * 2. Redistributions in binary form must reproduce the above copyright
  43  *    notice, this list of conditions and the following disclaimer in the
  44  *    documentation and/or other materials provided with the distribution.
  45  * 3. All advertising materials mentioning features or use of this software
  46  *    must display the following acknowledgement:
  47  *      This product includes software developed by the University of
  48  *      California, Berkeley and its contributors.
  49  * 4. Neither the name of the University nor the names of its contributors
  50  *    may be used to endorse or promote products derived from this software
  51  *    without specific prior written permission.
  52  *
  53  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  56  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  63  * SUCH DAMAGE.
  64  *
  65  *      @(#)quota.h
  66  *      derived from @(#)ufs/ufs/quota.h        8.3 (Berkeley) 8/19/94
  67  */
  68
  69 #ifndef _SYS_QUOTA_H
  70 #define _SYS_QUOTA_H
  71
  72 #include <sys/appleapiopts.h>
  73 #include <sys/cdefs.h>
  74 #ifdef KERNEL_PRIVATE
  75 #include <kern/locks.h>
  76 #endif
  77
  78 #include <mach/boolean.h>
  79
  80 #ifdef __APPLE_API_UNSTABLE
  81 /*
  82  * Definitions for disk quotas imposed on the average user
  83  * (big brother finally hits UNIX).
  84  *
  85  * The following constants define the amount of time given a user before the
  86  * soft limits are treated as hard limits (usually resulting in an allocation
  87  * failure). The timer is started when the user crosses their soft limit, it
  88  * is reset when they go below their soft limit.
  89  */
  90 #define MAX_IQ_TIME     (7*24*60*60)    /* seconds in 1 week */
  91 #define MAX_DQ_TIME     (7*24*60*60)    /* seconds in 1 week */
  92
  93 /*
  94  * The following constants define the usage of the quota file array in the
  95  * file system mount structure and dquot array in the inode structure.  The semantics
  96  * of the elements of these arrays are defined in the routine getinoquota;
  97  * the remainder of the quota code treats them generically and need not be
  98  * inspected when changing the size of the array.
  99  */
 100 #define MAXQUOTAS       2
 101 #define USRQUOTA        0       /* element used for user quotas */
 102 #define GRPQUOTA        1       /* element used for group quotas */
 103
 104 /*
 105  * Definitions for the default names of the quotas files.
 106  */
 107 #define INITQFNAMES { \
 108         "user",         /* USRQUOTA */ \
 109         "group",        /* GRPQUOTA */ \
 110         "undefined", \
 111 };
 112 #define QUOTAFILENAME   ".quota"
 113 #define QUOTAOPSNAME    ".quota.ops"
 114 #define QUOTAGROUP      "operator"
 115
 116 /*
 117  * Command definitions for the 'quotactl' system call.  The commands are
 118  * broken into a main command defined below and a subcommand that is used
 119  * to convey the type of quota that is being manipulated (see above).
 120  */
 121 #define SUBCMDMASK      0x00ff
 122 #define SUBCMDSHIFT     8
 123 #define QCMD(cmd, type) (((cmd) << SUBCMDSHIFT) | ((type) & SUBCMDMASK))
 124
 125 #define Q_QUOTAON       0x0100  /* enable quotas */
 126 #define Q_QUOTAOFF      0x0200  /* disable quotas */
 127 #define Q_GETQUOTA      0x0300  /* get limits and usage */
 128 #define Q_SETQUOTA      0x0400  /* set limits and usage */
 129 #define Q_SETUSE        0x0500  /* set usage */
 130 #define Q_SYNC          0x0600  /* sync disk copy of a filesystems quotas */
 131 #define Q_QUOTASTAT     0x0700  /* get quota on/off status */
 132
 133 /*
 134  * The following two structures define the format of the disk
 135  * quota file (as it appears on disk) - the file contains a
 136  * header followed by a hash table of dqblk entries.  To find
 137  * a particular entry, the user or group number (id) is first
 138  * converted to an index into this table by means of the hash
 139  * function dqhash1.  If there is a collision at that index
 140  * location then a second hash value is computed which using
 141  * dqhash2.  This second hash value is then used as an offset
 142  * to the next location to probe.  ID = 0 is used to indicate
 143  * an empty (unused) entry.  So there can never be an entry in
 144  * the quota file for user 0 or group 0 (which is OK since disk
 145  * quotas are never enforced for user 0).
 146  *
 147  * The setquota system call establishes the vnode for each quota
 148  * file (a pointer is retained in the filesystem  mount structure).
 149  */
 150 struct dqfilehdr {
 151         u_int32_t dqh_magic;
 152         u_int32_t dqh_version;          /* == QF_VERSION */
 153         u_int32_t dqh_maxentries;       /* must be a power of 2 */
 154         u_int32_t dqh_entrycnt;         /* count of active entries */
 155         u_int32_t dqh_flags;            /* reserved for now (0) */
 156         time_t    dqh_chktime;          /* time of last quota check */
 157         time_t    dqh_btime;            /* time limit for excessive disk use */
 158         time_t    dqh_itime;            /* time limit for excessive files */
 159         char      dqh_string[16];       /* tag string */
 160         u_int32_t dqh_spare[4];         /* pad struct to power of 2 */
 161 };
 162
 163 struct dqblk {
 164         u_int64_t dqb_bhardlimit;       /* absolute limit on disk bytes alloc */
 165         u_int64_t dqb_bsoftlimit;       /* preferred limit on disk bytes */
 166         u_int64_t dqb_curbytes;         /* current byte count */
 167         u_int32_t dqb_ihardlimit;       /* maximum # allocated inodes + 1 */
 168         u_int32_t dqb_isoftlimit;       /* preferred inode limit */
 169         u_int32_t dqb_curinodes;        /* current # allocated inodes */
 170         time_t    dqb_btime;            /* time limit for excessive disk use */
 171         time_t    dqb_itime;            /* time limit for excessive files */
 172         u_int32_t dqb_id;               /* identifier (0 for empty entries) */
 173         u_int32_t dqb_spare[4];         /* pad struct to power of 2 */
 174 };
 175
 176 #ifdef KERNEL_PRIVATE
 177 #include <machine/types.h>      /* user_time_t */
 178 /* LP64 version of struct dqblk.  time_t is a long and must grow when
 179  * we're dealing with a 64-bit process.
 180  * WARNING - keep in sync with struct dqblk
 181  */
 182
 183 #if __DARWIN_ALIGN_NATURAL
 184 #pragma options align=natural
 185 #endif
 186
 187 struct user_dqblk {
 188         u_int64_t dqb_bhardlimit;       /* absolute limit on disk bytes alloc */
 189         u_int64_t dqb_bsoftlimit;       /* preferred limit on disk bytes */
 190         u_int64_t dqb_curbytes;         /* current byte count */
 191         u_int32_t dqb_ihardlimit;       /* maximum # allocated inodes + 1 */
 192         u_int32_t dqb_isoftlimit;       /* preferred inode limit */
 193         u_int32_t dqb_curinodes;        /* current # allocated inodes */
 194         user_time_t       dqb_btime;            /* time limit for excessive disk use */
 195         user_time_t       dqb_itime;            /* time limit for excessive files */
 196         u_int32_t dqb_id;               /* identifier (0 for empty entries) */
 197         u_int32_t dqb_spare[4];         /* pad struct to power of 2 */
 198 };
 199
 200 #if __DARWIN_ALIGN_NATURAL
 201 #pragma options align=reset
 202 #endif
 203 #endif  /* KERNEL_PRIVATE */
 204
 205 #define INITQMAGICS { \
 206         0xff31ff35,     /* USRQUOTA */ \
 207         0xff31ff27,     /* GRPQUOTA */ \
 208 };
 209
 210 #define QF_VERSION          1
 211 #define QF_STRING_TAG       "QUOTA HASH FILE"
 212
 213 #define QF_USERS_PER_GB     256
 214 #define QF_MIN_USERS        2048
 215 #define QF_MAX_USERS       (2048*1024)
 216
 217 #define QF_GROUPS_PER_GB    32
 218 #define QF_MIN_GROUPS       2048
 219 #define QF_MAX_GROUPS       (256*1024)
 220
 221
 222 /*
 223  * The primary and secondary multiplicative hash functions are
 224  * derived from Knuth (vol. 3). They use a prime that is in
 225  * golden ratio to the machine's word size.
 226  */
 227 #define dqhash1(id, shift, mask)  \
 228         ((((id) * 2654435761UL) >> (shift)) & (mask))
 229
 230 #define dqhash2(id, mask)  \
 231         (dqhash1((id), 11, (mask)>>1) | 1)
 232
 233 /*
 234  * Compute a disk offset into a quota file.
 235  */
 236 #define dqoffset(index)  \
 237         (sizeof (struct dqfilehdr) + ((index) * sizeof (struct dqblk)))
 238 /*
 239  * Compute the hash shift value.
 240  * It is the word size, in bits, minus the hash table size, in bits.
 241  */
 242 static __inline int dqhashshift(u_long);
 243
 244 static __inline int
 245 dqhashshift(u_long size)
 246 {
 247         int shift;
 248
 249         for (shift = 32; size > 1; size >>= 1, --shift)
 250                 continue;
 251         return (shift);
 252 }
 253
 254
 255 #ifndef KERNEL
 256 __BEGIN_DECLS
 257 int quotactl(char *, int, int, caddr_t);
 258 __END_DECLS
 259 #endif /* !KERNEL */
 260
 261 #ifdef KERNEL_PRIVATE
 262 #include <sys/queue.h>
 263
 264
 265
 266 /* Quota file info
 267  */
 268 struct quotafile {
 269         lck_mtx_t     qf_lock;       /* quota file mutex */
 270         struct vnode *qf_vp;         /* quota file vnode */
 271         struct ucred *qf_cred;       /* quota file access cred */
 272         int           qf_shift;      /* primary hash shift */
 273         int           qf_maxentries; /* size of hash table (power of 2) */
 274         int           qf_entrycnt;   /* count of active entries */
 275         time_t        qf_btime;      /* block quota time limit */
 276         time_t        qf_itime;      /* inode quota time limit */
 277
 278                                      /* the following 2 fields are protected */
 279                                      /* by the quota list lock  */
 280         char          qf_qflags;     /* quota specific flags */
 281         int           qf_refcnt;     /* count of dquot refs on this file */
 282 };
 283
 284 /*
 285  * Flags describing the runtime state of quotas.
 286  * (in qf_qflags)
 287  */
 288 #define QTF_OPENING     0x01    /* Q_QUOTAON  in progress */
 289 #define QTF_CLOSING     0x02    /* Q_QUOTAOFF in progress */
 290 #define QTF_WANTED      0x04    /* waiting for change of state */
 291
 292
 293 /*
 294  * The following structure records disk usage for a user or group on a
 295  * filesystem. There is one allocated for each quota that exists on any
 296  * filesystem for the current user or group. A cache is kept of recently
 297  * used entries.
 298  */
 299 struct dquot {
 300         LIST_ENTRY(dquot) dq_hash;      /* hash list */
 301         TAILQ_ENTRY(dquot) dq_freelist; /* free list */
 302         u_int16_t dq_flags;             /* flags, see below */
 303         u_int16_t dq_cnt;               /* count of active references */
 304         u_int16_t dq_lflags;            /* protected by the quota list lock */
 305         u_int16_t dq_type;              /* quota type of this dquot */
 306         u_int32_t dq_id;                /* identifier this applies to */
 307         u_int32_t dq_index;             /* index into quota file */
 308         struct  quotafile *dq_qfile;    /* quota file that this is taken from */
 309         struct  dqblk dq_dqb;           /* actual usage & quotas */
 310 };
 311
 312 /*
 313  * dq_lflags values
 314  */
 315 #define DQ_LLOCK        0x01            /* this quota locked (no MODS) */
 316 #define DQ_LWANT        0x02            /* wakeup on unlock */
 317
 318 /*
 319  * dq_flags values
 320  */
 321 #define DQ_MOD          0x01            /* this quota modified since read */
 322 #define DQ_FAKE         0x02            /* no limits here, just usage */
 323 #define DQ_BLKS         0x04            /* has been warned about blk limit */
 324 #define DQ_INODS        0x08            /* has been warned about inode limit */
 325
 326 /*
 327  * Shorthand notation.
 328  */
 329 #define dq_bhardlimit   dq_dqb.dqb_bhardlimit
 330 #define dq_bsoftlimit   dq_dqb.dqb_bsoftlimit
 331 #define dq_curbytes     dq_dqb.dqb_curbytes
 332 #define dq_ihardlimit   dq_dqb.dqb_ihardlimit
 333 #define dq_isoftlimit   dq_dqb.dqb_isoftlimit
 334 #define dq_curinodes    dq_dqb.dqb_curinodes
 335 #define dq_btime        dq_dqb.dqb_btime
 336 #define dq_itime        dq_dqb.dqb_itime
 337
 338 /*
 339  * If the system has never checked for a quota for this file, then it is
 340  * set to NODQUOT.  Once a write attempt is made the inode pointer is set
 341  * to reference a dquot structure.
 342  */
 343 #define NODQUOT         NULL
 344
 345 /*
 346  * Flags to chkdq() and chkiq()
 347  */
 348 #define FORCE   0x01    /* force usage changes independent of limits */
 349 #define CHOWN   0x02    /* (advisory) change initiated by chown */
 350
 351
 352 /*
 353  * Functions that manage the in-core dquot and the
 354  * on-disk dqblk data structures.
 355  */
 356 __BEGIN_DECLS
 357 void    dqfileinit(struct quotafile *);
 358 int     dqfileopen(struct quotafile *, int);
 359 void    dqfileclose(struct quotafile *, int);
 360 void    dqflush(struct vnode *);
 361 int     dqget(u_long, struct quotafile *, int, struct dquot **);
 362 void    dqinit(void);
 363 void    dqref(struct dquot *);
 364 void    dqrele(struct dquot *);
 365 void    dqreclaim(struct dquot *);
 366 int     dqsync(struct dquot *);
 367 void    dqsync_orphans(struct quotafile *);
 368 void    dqlock(struct dquot *);
 369 void    dqunlock(struct dquot *);
 370
 371 int     qf_get(struct quotafile *, int type);
 372 void    qf_put(struct quotafile *, int type);
 373
 374 __private_extern__ void  munge_dqblk(struct dqblk *dqblkp, struct user_dqblk *user_dqblkp, boolean_t to64);
 375 __END_DECLS
 376
 377 #endif /* KERNEL_PRIVATE */
 378
 379 #endif /* __APPLE_API_UNSTABLE */
 380
 381 #endif /* !_SYS_QUOTA_H_ */