bsd/sys/quota.h

   1 /*
   2  * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Copyright (c) 1982, 1986, 1993
  24  *      The Regents of the University of California.  All rights reserved.
  25  *
  26  * This code is derived from software contributed to Berkeley by
  27  * Robert Elz at The University of Melbourne.
  28  *
  29  * Redistribution and use in source and binary forms, with or without
  30  * modification, are permitted provided that the following conditions
  31  * are met:
  32  * 1. Redistributions of source code must retain the above copyright
  33  *    notice, this list of conditions and the following disclaimer.
  34  * 2. Redistributions in binary form must reproduce the above copyright
  35  *    notice, this list of conditions and the following disclaimer in the
  36  *    documentation and/or other materials provided with the distribution.
  37  * 3. All advertising materials mentioning features or use of this software
  38  *    must display the following acknowledgement:
  39  *      This product includes software developed by the University of
  40  *      California, Berkeley and its contributors.
  41  * 4. Neither the name of the University nor the names of its contributors
  42  *    may be used to endorse or promote products derived from this software
  43  *    without specific prior written permission.
  44  *
  45  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  46  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  47  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  48  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  49  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  50  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  51  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  52  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  53  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  54  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  55  * SUCH DAMAGE.
  56  *
  57  *      @(#)quota.h
  58  *      derived from @(#)ufs/ufs/quota.h        8.3 (Berkeley) 8/19/94
  59  */
  60
  61 #ifndef _SYS_QUOTA_H
  62 #define _SYS_QUOTA_H
  63
  64 #include <sys/appleapiopts.h>
  65 #include <sys/cdefs.h>
  66 #ifdef KERNEL_PRIVATE
  67 #include <kern/locks.h>
  68 #endif
  69
  70 #include <mach/boolean.h>
  71
  72 #ifdef __APPLE_API_UNSTABLE
  73 /*
  74  * Definitions for disk quotas imposed on the average user
  75  * (big brother finally hits UNIX).
  76  *
  77  * The following constants define the amount of time given a user before the
  78  * soft limits are treated as hard limits (usually resulting in an allocation
  79  * failure). The timer is started when the user crosses their soft limit, it
  80  * is reset when they go below their soft limit.
  81  */
  82 #define MAX_IQ_TIME     (7*24*60*60)    /* seconds in 1 week */
  83 #define MAX_DQ_TIME     (7*24*60*60)    /* seconds in 1 week */
  84
  85 /*
  86  * The following constants define the usage of the quota file array in the
  87  * file system mount structure and dquot array in the inode structure.  The semantics
  88  * of the elements of these arrays are defined in the routine getinoquota;
  89  * the remainder of the quota code treats them generically and need not be
  90  * inspected when changing the size of the array.
  91  */
  92 #define MAXQUOTAS       2
  93 #define USRQUOTA        0       /* element used for user quotas */
  94 #define GRPQUOTA        1       /* element used for group quotas */
  95
  96 /*
  97  * Definitions for the default names of the quotas files.
  98  */
  99 #define INITQFNAMES { \
 100         "user",         /* USRQUOTA */ \
 101         "group",        /* GRPQUOTA */ \
 102         "undefined", \
 103 };
 104 #define QUOTAFILENAME   ".quota"
 105 #define QUOTAOPSNAME    ".quota.ops"
 106 #define QUOTAGROUP      "operator"
 107
 108 /*
 109  * Command definitions for the 'quotactl' system call.  The commands are
 110  * broken into a main command defined below and a subcommand that is used
 111  * to convey the type of quota that is being manipulated (see above).
 112  */
 113 #define SUBCMDMASK      0x00ff
 114 #define SUBCMDSHIFT     8
 115 #define QCMD(cmd, type) (((cmd) << SUBCMDSHIFT) | ((type) & SUBCMDMASK))
 116
 117 #define Q_QUOTAON       0x0100  /* enable quotas */
 118 #define Q_QUOTAOFF      0x0200  /* disable quotas */
 119 #define Q_GETQUOTA      0x0300  /* get limits and usage */
 120 #define Q_SETQUOTA      0x0400  /* set limits and usage */
 121 #define Q_SETUSE        0x0500  /* set usage */
 122 #define Q_SYNC          0x0600  /* sync disk copy of a filesystems quotas */
 123 #define Q_QUOTASTAT     0x0700  /* get quota on/off status */
 124
 125 /*
 126  * The following two structures define the format of the disk
 127  * quota file (as it appears on disk) - the file contains a
 128  * header followed by a hash table of dqblk entries.  To find
 129  * a particular entry, the user or group number (id) is first
 130  * converted to an index into this table by means of the hash
 131  * function dqhash1.  If there is a collision at that index
 132  * location then a second hash value is computed which using
 133  * dqhash2.  This second hash value is then used as an offset
 134  * to the next location to probe.  ID = 0 is used to indicate
 135  * an empty (unused) entry.  So there can never be an entry in
 136  * the quota file for user 0 or group 0 (which is OK since disk
 137  * quotas are never enforced for user 0).
 138  *
 139  * The setquota system call establishes the vnode for each quota
 140  * file (a pointer is retained in the filesystem  mount structure).
 141  */
 142 struct dqfilehdr {
 143         u_int32_t dqh_magic;
 144         u_int32_t dqh_version;          /* == QF_VERSION */
 145         u_int32_t dqh_maxentries;       /* must be a power of 2 */
 146         u_int32_t dqh_entrycnt;         /* count of active entries */
 147         u_int32_t dqh_flags;            /* reserved for now (0) */
 148         time_t    dqh_chktime;          /* time of last quota check */
 149         time_t    dqh_btime;            /* time limit for excessive disk use */
 150         time_t    dqh_itime;            /* time limit for excessive files */
 151         char      dqh_string[16];       /* tag string */
 152         u_int32_t dqh_spare[4];         /* pad struct to power of 2 */
 153 };
 154
 155 struct dqblk {
 156         u_int64_t dqb_bhardlimit;       /* absolute limit on disk bytes alloc */
 157         u_int64_t dqb_bsoftlimit;       /* preferred limit on disk bytes */
 158         u_int64_t dqb_curbytes;         /* current byte count */
 159         u_int32_t dqb_ihardlimit;       /* maximum # allocated inodes + 1 */
 160         u_int32_t dqb_isoftlimit;       /* preferred inode limit */
 161         u_int32_t dqb_curinodes;        /* current # allocated inodes */
 162         time_t    dqb_btime;            /* time limit for excessive disk use */
 163         time_t    dqb_itime;            /* time limit for excessive files */
 164         u_int32_t dqb_id;               /* identifier (0 for empty entries) */
 165         u_int32_t dqb_spare[4];         /* pad struct to power of 2 */
 166 };
 167
 168 #ifdef KERNEL_PRIVATE
 169 #include <machine/types.h>      /* user_time_t */
 170 /* LP64 version of struct dqblk.  time_t is a long and must grow when
 171  * we're dealing with a 64-bit process.
 172  * WARNING - keep in sync with struct dqblk
 173  */
 174
 175 struct user_dqblk {
 176         u_int64_t dqb_bhardlimit;       /* absolute limit on disk bytes alloc */
 177         u_int64_t dqb_bsoftlimit;       /* preferred limit on disk bytes */
 178         u_int64_t dqb_curbytes;         /* current byte count */
 179         u_int32_t dqb_ihardlimit;       /* maximum # allocated inodes + 1 */
 180         u_int32_t dqb_isoftlimit;       /* preferred inode limit */
 181         u_int32_t dqb_curinodes;        /* current # allocated inodes */
 182         user_time_t       dqb_btime __attribute((aligned(8)));          /* time limit for excessive disk use */
 183         user_time_t       dqb_itime;            /* time limit for excessive files */
 184         u_int32_t dqb_id;               /* identifier (0 for empty entries) */
 185         u_int32_t dqb_spare[4];         /* pad struct to power of 2 */
 186 };
 187 #endif  /* KERNEL_PRIVATE */
 188
 189 #define INITQMAGICS { \
 190         0xff31ff35,     /* USRQUOTA */ \
 191         0xff31ff27,     /* GRPQUOTA */ \
 192 };
 193
 194 #define QF_VERSION          1
 195 #define QF_STRING_TAG       "QUOTA HASH FILE"
 196
 197 #define QF_USERS_PER_GB     256
 198 #define QF_MIN_USERS        2048
 199 #define QF_MAX_USERS       (2048*1024)
 200
 201 #define QF_GROUPS_PER_GB    32
 202 #define QF_MIN_GROUPS       2048
 203 #define QF_MAX_GROUPS       (256*1024)
 204
 205
 206 /*
 207  * The primary and secondary multiplicative hash functions are
 208  * derived from Knuth (vol. 3). They use a prime that is in
 209  * golden ratio to the machine's word size.
 210  */
 211 #define dqhash1(id, shift, mask)  \
 212         ((((id) * 2654435761UL) >> (shift)) & (mask))
 213
 214 #define dqhash2(id, mask)  \
 215         (dqhash1((id), 11, (mask)>>1) | 1)
 216
 217 /*
 218  * Compute a disk offset into a quota file.
 219  */
 220 #define dqoffset(index)  \
 221         (sizeof (struct dqfilehdr) + ((index) * sizeof (struct dqblk)))
 222 /*
 223  * Compute the hash shift value.
 224  * It is the word size, in bits, minus the hash table size, in bits.
 225  */
 226 static __inline int dqhashshift(u_long);
 227
 228 static __inline int
 229 dqhashshift(u_long size)
 230 {
 231         int shift;
 232
 233         for (shift = 32; size > 1; size >>= 1, --shift)
 234                 continue;
 235         return (shift);
 236 }
 237
 238
 239 #ifndef KERNEL
 240 __BEGIN_DECLS
 241 int quotactl(char *, int, int, caddr_t);
 242 __END_DECLS
 243 #endif /* !KERNEL */
 244
 245 #ifdef KERNEL_PRIVATE
 246 #include <sys/queue.h>
 247
 248
 249
 250 /* Quota file info
 251  */
 252 struct quotafile {
 253         lck_mtx_t     qf_lock;       /* quota file mutex */
 254         struct vnode *qf_vp;         /* quota file vnode */
 255         struct ucred *qf_cred;       /* quota file access cred */
 256         int           qf_shift;      /* primary hash shift */
 257         int           qf_maxentries; /* size of hash table (power of 2) */
 258         int           qf_entrycnt;   /* count of active entries */
 259         time_t        qf_btime;      /* block quota time limit */
 260         time_t        qf_itime;      /* inode quota time limit */
 261
 262                                      /* the following 2 fields are protected */
 263                                      /* by the quota list lock  */
 264         char          qf_qflags;     /* quota specific flags */
 265         int           qf_refcnt;     /* count of dquot refs on this file */
 266 };
 267
 268 /*
 269  * Flags describing the runtime state of quotas.
 270  * (in qf_qflags)
 271  */
 272 #define QTF_OPENING     0x01    /* Q_QUOTAON  in progress */
 273 #define QTF_CLOSING     0x02    /* Q_QUOTAOFF in progress */
 274 #define QTF_WANTED      0x04    /* waiting for change of state */
 275
 276
 277 /*
 278  * The following structure records disk usage for a user or group on a
 279  * filesystem. There is one allocated for each quota that exists on any
 280  * filesystem for the current user or group. A cache is kept of recently
 281  * used entries.
 282  */
 283 struct dquot {
 284         LIST_ENTRY(dquot) dq_hash;      /* hash list */
 285         TAILQ_ENTRY(dquot) dq_freelist; /* free list */
 286         uint32_t  dq_cnt;               /* count of active references */
 287         u_int16_t dq_flags;             /* flags, see below */
 288         u_int16_t dq_lflags;            /* protected by the quota list lock */
 289         u_int16_t dq_type;              /* quota type of this dquot */
 290         u_int32_t dq_id;                /* identifier this applies to */
 291         u_int32_t dq_index;             /* index into quota file */
 292         struct  quotafile *dq_qfile;    /* quota file that this is taken from */
 293         struct  dqblk dq_dqb;           /* actual usage & quotas */
 294 };
 295
 296 /*
 297  * dq_lflags values
 298  */
 299 #define DQ_LLOCK        0x01            /* this quota locked (no MODS) */
 300 #define DQ_LWANT        0x02            /* wakeup on unlock */
 301
 302 /*
 303  * dq_flags values
 304  */
 305 #define DQ_MOD          0x01            /* this quota modified since read */
 306 #define DQ_FAKE         0x02            /* no limits here, just usage */
 307 #define DQ_BLKS         0x04            /* has been warned about blk limit */
 308 #define DQ_INODS        0x08            /* has been warned about inode limit */
 309
 310 /*
 311  * Shorthand notation.
 312  */
 313 #define dq_bhardlimit   dq_dqb.dqb_bhardlimit
 314 #define dq_bsoftlimit   dq_dqb.dqb_bsoftlimit
 315 #define dq_curbytes     dq_dqb.dqb_curbytes
 316 #define dq_ihardlimit   dq_dqb.dqb_ihardlimit
 317 #define dq_isoftlimit   dq_dqb.dqb_isoftlimit
 318 #define dq_curinodes    dq_dqb.dqb_curinodes
 319 #define dq_btime        dq_dqb.dqb_btime
 320 #define dq_itime        dq_dqb.dqb_itime
 321
 322 /*
 323  * If the system has never checked for a quota for this file, then it is
 324  * set to NODQUOT.  Once a write attempt is made the inode pointer is set
 325  * to reference a dquot structure.
 326  */
 327 #define NODQUOT         NULL
 328
 329 /*
 330  * Flags to chkdq() and chkiq()
 331  */
 332 #define FORCE   0x01    /* force usage changes independent of limits */
 333 #define CHOWN   0x02    /* (advisory) change initiated by chown */
 334
 335
 336 /*
 337  * Functions that manage the in-core dquot and the
 338  * on-disk dqblk data structures.
 339  */
 340 __BEGIN_DECLS
 341 void    dqfileinit(struct quotafile *);
 342 int     dqfileopen(struct quotafile *, int);
 343 void    dqfileclose(struct quotafile *, int);
 344 void    dqflush(struct vnode *);
 345 int     dqget(u_long, struct quotafile *, int, struct dquot **);
 346 void    dqinit(void);
 347 void    dqref(struct dquot *);
 348 void    dqrele(struct dquot *);
 349 void    dqreclaim(struct dquot *);
 350 int     dqsync(struct dquot *);
 351 void    dqsync_orphans(struct quotafile *);
 352 void    dqlock(struct dquot *);
 353 void    dqunlock(struct dquot *);
 354
 355 int     qf_get(struct quotafile *, int type);
 356 void    qf_put(struct quotafile *, int type);
 357
 358 __private_extern__ void  munge_dqblk(struct dqblk *dqblkp, struct user_dqblk *user_dqblkp, boolean_t to64);
 359 __END_DECLS
 360
 361 #endif /* KERNEL_PRIVATE */
 362
 363 #endif /* __APPLE_API_UNSTABLE */
 364
 365 #endif /* !_SYS_QUOTA_H_ */