bsd/sys/quota.h

   1 /*
   2  * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_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 License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * Copyright (c) 1982, 1986, 1993
  30  *      The Regents of the University of California.  All rights reserved.
  31  *
  32  * This code is derived from software contributed to Berkeley by
  33  * Robert Elz at The University of Melbourne.
  34  *
  35  * Redistribution and use in source and binary forms, with or without
  36  * modification, are permitted provided that the following conditions
  37  * are met:
  38  * 1. Redistributions of source code must retain the above copyright
  39  *    notice, this list of conditions and the following disclaimer.
  40  * 2. Redistributions in binary form must reproduce the above copyright
  41  *    notice, this list of conditions and the following disclaimer in the
  42  *    documentation and/or other materials provided with the distribution.
  43  * 3. All advertising materials mentioning features or use of this software
  44  *    must display the following acknowledgement:
  45  *      This product includes software developed by the University of
  46  *      California, Berkeley and its contributors.
  47  * 4. Neither the name of the University nor the names of its contributors
  48  *    may be used to endorse or promote products derived from this software
  49  *    without specific prior written permission.
  50  *
  51  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  52  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  53  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  54  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  55  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  56  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  57  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  58  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  59  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  60  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  61  * SUCH DAMAGE.
  62  *
  63  *      @(#)quota.h
  64  *      derived from @(#)ufs/ufs/quota.h        8.3 (Berkeley) 8/19/94
  65  */
  66
  67 #ifndef _SYS_QUOTA_H
  68 #define _SYS_QUOTA_H
  69
  70 #include <sys/appleapiopts.h>
  71 #include <sys/cdefs.h>
  72 #ifdef KERNEL_PRIVATE
  73 #include <kern/locks.h>
  74 #endif
  75
  76 #include <mach/boolean.h>
  77
  78 #ifdef __APPLE_API_UNSTABLE
  79 /*
  80  * Definitions for disk quotas imposed on the average user
  81  * (big brother finally hits UNIX).
  82  *
  83  * The following constants define the amount of time given a user before the
  84  * soft limits are treated as hard limits (usually resulting in an allocation
  85  * failure). The timer is started when the user crosses their soft limit, it
  86  * is reset when they go below their soft limit.
  87  */
  88 #define MAX_IQ_TIME     (7*24*60*60)    /* seconds in 1 week */
  89 #define MAX_DQ_TIME     (7*24*60*60)    /* seconds in 1 week */
  90
  91 /*
  92  * The following constants define the usage of the quota file array in the
  93  * file system mount structure and dquot array in the inode structure.  The semantics
  94  * of the elements of these arrays are defined in the routine getinoquota;
  95  * the remainder of the quota code treats them generically and need not be
  96  * inspected when changing the size of the array.
  97  */
  98 #define MAXQUOTAS       2
  99 #define USRQUOTA        0       /* element used for user quotas */
 100 #define GRPQUOTA        1       /* element used for group quotas */
 101
 102 /*
 103  * Definitions for the default names of the quotas files.
 104  */
 105 #define INITQFNAMES { \
 106         "user",         /* USRQUOTA */ \
 107         "group",        /* GRPQUOTA */ \
 108         "undefined", \
 109 };
 110 #define QUOTAFILENAME   ".quota"
 111 #define QUOTAOPSNAME    ".quota.ops"
 112 #define QUOTAGROUP      "operator"
 113
 114 /*
 115  * Command definitions for the 'quotactl' system call.  The commands are
 116  * broken into a main command defined below and a subcommand that is used
 117  * to convey the type of quota that is being manipulated (see above).
 118  */
 119 #define SUBCMDMASK      0x00ff
 120 #define SUBCMDSHIFT     8
 121 #define QCMD(cmd, type) (((cmd) << SUBCMDSHIFT) | ((type) & SUBCMDMASK))
 122
 123 #define Q_QUOTAON       0x0100  /* enable quotas */
 124 #define Q_QUOTAOFF      0x0200  /* disable quotas */
 125 #define Q_GETQUOTA      0x0300  /* get limits and usage */
 126 #define Q_SETQUOTA      0x0400  /* set limits and usage */
 127 #define Q_SETUSE        0x0500  /* set usage */
 128 #define Q_SYNC          0x0600  /* sync disk copy of a filesystems quotas */
 129 #define Q_QUOTASTAT     0x0700  /* get quota on/off status */
 130
 131 /*
 132  * The following two structures define the format of the disk
 133  * quota file (as it appears on disk) - the file contains a
 134  * header followed by a hash table of dqblk entries.  To find
 135  * a particular entry, the user or group number (id) is first
 136  * converted to an index into this table by means of the hash
 137  * function dqhash1.  If there is a collision at that index
 138  * location then a second hash value is computed which using
 139  * dqhash2.  This second hash value is then used as an offset
 140  * to the next location to probe.  ID = 0 is used to indicate
 141  * an empty (unused) entry.  So there can never be an entry in
 142  * the quota file for user 0 or group 0 (which is OK since disk
 143  * quotas are never enforced for user 0).
 144  *
 145  * The setquota system call establishes the vnode for each quota
 146  * file (a pointer is retained in the filesystem  mount structure).
 147  */
 148 struct dqfilehdr {
 149         u_int32_t dqh_magic;
 150         u_int32_t dqh_version;          /* == QF_VERSION */
 151         u_int32_t dqh_maxentries;       /* must be a power of 2 */
 152         u_int32_t dqh_entrycnt;         /* count of active entries */
 153         u_int32_t dqh_flags;            /* reserved for now (0) */
 154         u_int32_t dqh_chktime;          /* time of last quota check */
 155         u_int32_t dqh_btime;            /* time limit for excessive disk use */
 156         u_int32_t dqh_itime;            /* time limit for excessive files */
 157         char      dqh_string[16];       /* tag string */
 158         u_int32_t dqh_spare[4];         /* pad struct to power of 2 */
 159 };
 160
 161 struct dqblk {
 162         u_int64_t dqb_bhardlimit;       /* absolute limit on disk bytes alloc */
 163         u_int64_t dqb_bsoftlimit;       /* preferred limit on disk bytes */
 164         u_int64_t dqb_curbytes;         /* current byte count */
 165         u_int32_t dqb_ihardlimit;       /* maximum # allocated inodes + 1 */
 166         u_int32_t dqb_isoftlimit;       /* preferred inode limit */
 167         u_int32_t dqb_curinodes;        /* current # allocated inodes */
 168         u_int32_t dqb_btime;            /* time limit for excessive disk use */
 169         u_int32_t dqb_itime;            /* time limit for excessive files */
 170         u_int32_t dqb_id;               /* identifier (0 for empty entries) */
 171         u_int32_t dqb_spare[4];         /* pad struct to power of 2 */
 172 };
 173
 174 #ifdef KERNEL_PRIVATE
 175 #include <machine/types.h>      /* user_time_t */
 176 /* LP64 version of struct dqblk.  time_t is a long and must grow when
 177  * we're dealing with a 64-bit process.
 178  * WARNING - keep in sync with struct dqblk
 179  */
 180
 181 struct user_dqblk {
 182         u_int64_t dqb_bhardlimit;       /* absolute limit on disk bytes alloc */
 183         u_int64_t dqb_bsoftlimit;       /* preferred limit on disk bytes */
 184         u_int64_t dqb_curbytes;         /* current byte count */
 185         u_int32_t dqb_ihardlimit;       /* maximum # allocated inodes + 1 */
 186         u_int32_t dqb_isoftlimit;       /* preferred inode limit */
 187         u_int32_t dqb_curinodes;        /* current # allocated inodes */
 188         u_int32_t dqb_btime;            /* time limit for excessive disk use */
 189         u_int32_t dqb_itime;            /* time limit for excessive files */
 190         u_int32_t dqb_id;               /* identifier (0 for empty entries) */
 191         u_int32_t dqb_spare[4];         /* pad struct to power of 2 */
 192 };
 193 #endif  /* KERNEL_PRIVATE */
 194
 195 #define INITQMAGICS { \
 196         0xff31ff35,     /* USRQUOTA */ \
 197         0xff31ff27,     /* GRPQUOTA */ \
 198 };
 199
 200 #define QF_VERSION          1
 201 #define QF_STRING_TAG       "QUOTA HASH FILE"
 202
 203 #define QF_USERS_PER_GB     256
 204 #define QF_MIN_USERS        2048
 205 #define QF_MAX_USERS       (2048*1024)
 206
 207 #define QF_GROUPS_PER_GB    32
 208 #define QF_MIN_GROUPS       2048
 209 #define QF_MAX_GROUPS       (256*1024)
 210
 211
 212 /*
 213  * The primary and secondary multiplicative hash functions are
 214  * derived from Knuth (vol. 3). They use a prime that is in
 215  * golden ratio to the machine's word size.
 216  */
 217 #define dqhash1(id, shift, mask)  \
 218         ((((id) * 2654435761U) >> (shift)) & (mask))
 219
 220 #define dqhash2(id, mask)  \
 221         (dqhash1((id), 11, (mask)>>1) | 1)
 222
 223 /*
 224  * Compute a disk offset into a quota file.
 225  */
 226 #define dqoffset(index)  \
 227         (sizeof (struct dqfilehdr) + ((index) * sizeof (struct dqblk)))
 228 /*
 229  * Compute the hash shift value.
 230  * It is the word size, in bits, minus the hash table size, in bits.
 231  */
 232 static __inline int dqhashshift(u_int32_t);
 233
 234 static __inline int
 235 dqhashshift(u_int32_t size)
 236 {
 237         int shift;
 238
 239         for (shift = 32; size > 1; size >>= 1, --shift)
 240                 continue;
 241         return (shift);
 242 }
 243
 244
 245 #ifndef KERNEL
 246 __BEGIN_DECLS
 247 int quotactl(const char *, int, int, caddr_t);
 248 __END_DECLS
 249 #endif /* !KERNEL */
 250
 251 #ifdef KERNEL_PRIVATE
 252 #include <sys/queue.h>
 253
 254
 255
 256 /* Quota file info
 257  */
 258 struct quotafile {
 259         lck_mtx_t     qf_lock;       /* quota file mutex */
 260         struct vnode *qf_vp;         /* quota file vnode */
 261         kauth_cred_t  qf_cred;       /* quota file access cred */
 262         int           qf_shift;      /* primary hash shift */
 263         int           qf_maxentries; /* size of hash table (power of 2) */
 264         int           qf_entrycnt;   /* count of active entries */
 265         u_int32_t     qf_btime;      /* block quota time limit */
 266         u_int32_t     qf_itime;      /* inode quota time limit */
 267
 268                                      /* the following 2 fields are protected */
 269                                      /* by the quota list lock  */
 270         char          qf_qflags;     /* quota specific flags */
 271         int           qf_refcnt;     /* count of dquot refs on this file */
 272 };
 273
 274 /*
 275  * Flags describing the runtime state of quotas.
 276  * (in qf_qflags)
 277  */
 278 #define QTF_OPENING     0x01    /* Q_QUOTAON  in progress */
 279 #define QTF_CLOSING     0x02    /* Q_QUOTAOFF in progress */
 280 #define QTF_WANTED      0x04    /* waiting for change of state */
 281
 282
 283 /*
 284  * The following structure records disk usage for a user or group on a
 285  * filesystem. There is one allocated for each quota that exists on any
 286  * filesystem for the current user or group. A cache is kept of recently
 287  * used entries.
 288  */
 289 struct dquot {
 290         LIST_ENTRY(dquot) dq_hash;      /* hash list */
 291         TAILQ_ENTRY(dquot) dq_freelist; /* free list */
 292         u_int16_t dq_flags;             /* flags, see below */
 293         u_int16_t dq_cnt_unused;        /* Replaced by dq_cnt below */
 294         u_int16_t dq_lflags;            /* protected by the quota list lock */
 295         u_int16_t dq_type;              /* quota type of this dquot */
 296         u_int32_t dq_id;                /* identifier this applies to */
 297         u_int32_t dq_index;             /* index into quota file */
 298         struct  quotafile *dq_qfile;    /* quota file that this is taken from */
 299         struct  dqblk dq_dqb;           /* actual usage & quotas */
 300         uint32_t  dq_cnt;               /* count of active references */
 301 };
 302
 303 /*
 304  * dq_lflags values
 305  */
 306 #define DQ_LLOCK        0x01            /* this quota locked (no MODS) */
 307 #define DQ_LWANT        0x02            /* wakeup on unlock */
 308
 309 /*
 310  * dq_flags values
 311  */
 312 #define DQ_MOD          0x01            /* this quota modified since read */
 313 #define DQ_FAKE         0x02            /* no limits here, just usage */
 314 #define DQ_BLKS         0x04            /* has been warned about blk limit */
 315 #define DQ_INODS        0x08            /* has been warned about inode limit */
 316
 317 /*
 318  * Shorthand notation.
 319  */
 320 #define dq_bhardlimit   dq_dqb.dqb_bhardlimit
 321 #define dq_bsoftlimit   dq_dqb.dqb_bsoftlimit
 322 #define dq_curbytes     dq_dqb.dqb_curbytes
 323 #define dq_ihardlimit   dq_dqb.dqb_ihardlimit
 324 #define dq_isoftlimit   dq_dqb.dqb_isoftlimit
 325 #define dq_curinodes    dq_dqb.dqb_curinodes
 326 #define dq_btime        dq_dqb.dqb_btime
 327 #define dq_itime        dq_dqb.dqb_itime
 328
 329 /*
 330  * If the system has never checked for a quota for this file, then it is
 331  * set to NODQUOT.  Once a write attempt is made the inode pointer is set
 332  * to reference a dquot structure.
 333  */
 334 #define NODQUOT         NULL
 335
 336 /*
 337  * Flags to chkdq() and chkiq()
 338  */
 339 #define FORCE   0x01    /* force usage changes independent of limits */
 340 #define CHOWN   0x02    /* (advisory) change initiated by chown */
 341
 342
 343 #ifdef XNU_KERNEL_PRIVATE
 344 /*
 345  * Functions that manage the in-core dquot and the
 346  * on-disk dqblk data structures.
 347  */
 348 __BEGIN_DECLS
 349 void    dqfileinit(struct quotafile *);
 350 int     dqfileopen(struct quotafile *, int);
 351 void    dqfileclose(struct quotafile *, int);
 352 void    dqflush(struct vnode *);
 353 int     dqget(u_int32_t, struct quotafile *, int, struct dquot **);
 354 void    dqhashinit(void);
 355 void    dqinit(void);
 356 int     dqisinitialized(void);
 357 void    dqref(struct dquot *);
 358 void    dqrele(struct dquot *);
 359 void    dqreclaim(struct dquot *);
 360 int     dqsync(struct dquot *);
 361 void    dqsync_orphans(struct quotafile *);
 362 void    dqlock(struct dquot *);
 363 void    dqunlock(struct dquot *);
 364
 365 int     qf_get(struct quotafile *, int type);
 366 void    qf_put(struct quotafile *, int type);
 367
 368 __private_extern__ void  munge_dqblk(struct dqblk *dqblkp, struct user_dqblk *user_dqblkp, boolean_t to64);
 369 __END_DECLS
 370 #endif /* XNU_KERNEL_PRIVATE */
 371
 372 #endif /* KERNEL_PRIVATE */
 373
 374 #endif /* __APPLE_API_UNSTABLE */
 375
 376 #endif /* !_SYS_QUOTA_H_ */