The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/sys/param.h

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * SPDX-License-Identifier: BSD-3-Clause
    3  *
    4  * Copyright (c) 1982, 1986, 1989, 1993
    5  *      The Regents of the University of California.  All rights reserved.
    6  * (c) UNIX System Laboratories, Inc.
    7  * All or some portions of this file are derived from material licensed
    8  * to the University of California by American Telephone and Telegraph
    9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
   10  * the permission of UNIX System Laboratories, Inc.
   11  *
   12  * Redistribution and use in source and binary forms, with or without
   13  * modification, are permitted provided that the following conditions
   14  * are met:
   15  * 1. Redistributions of source code must retain the above copyright
   16  *    notice, this list of conditions and the following disclaimer.
   17  * 2. Redistributions in binary form must reproduce the above copyright
   18  *    notice, this list of conditions and the following disclaimer in the
   19  *    documentation and/or other materials provided with the distribution.
   20  * 3. Neither the name of the University nor the names of its contributors
   21  *    may be used to endorse or promote products derived from this software
   22  *    without specific prior written permission.
   23  *
   24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   34  * SUCH DAMAGE.
   35  *
   36  *      @(#)param.h     8.3 (Berkeley) 4/4/95
   37  * $FreeBSD: releng/12.0/sys/sys/param.h 339732 2018-10-25 15:49:59Z kib $
   38  */
   39 
   40 #ifndef _SYS_PARAM_H_
   41 #define _SYS_PARAM_H_
   42 
   43 #include <sys/_null.h>
   44 
   45 #define BSD     199506          /* System version (year & month). */
   46 #define BSD4_3  1
   47 #define BSD4_4  1
   48 
   49 /*
   50  * __FreeBSD_version numbers are documented in the Porter's Handbook.
   51  * If you bump the version for any reason, you should update the documentation
   52  * there.
   53  * Currently this lives here in the doc/ repository:
   54  *
   55  *      head/en_US.ISO8859-1/books/porters-handbook/versions/chapter.xml
   56  *
   57  * scheme is:  <major><two digit minor>Rxx
   58  *              'R' is in the range 0 to 4 if this is a release branch or
   59  *              X.0-CURRENT before releng/X.0 is created, otherwise 'R' is
   60  *              in the range 5 to 9.
   61  */
   62 #undef __FreeBSD_version
   63 #define __FreeBSD_version 1200086       /* Master, propagated to newvers */
   64 
   65 /*
   66  * __FreeBSD_kernel__ indicates that this system uses the kernel of FreeBSD,
   67  * which by definition is always true on FreeBSD. This macro is also defined
   68  * on other systems that use the kernel of FreeBSD, such as GNU/kFreeBSD.
   69  *
   70  * It is tempting to use this macro in userland code when we want to enable
   71  * kernel-specific routines, and in fact it's fine to do this in code that
   72  * is part of FreeBSD itself.  However, be aware that as presence of this
   73  * macro is still not widespread (e.g. older FreeBSD versions, 3rd party
   74  * compilers, etc), it is STRONGLY DISCOURAGED to check for this macro in
   75  * external applications without also checking for __FreeBSD__ as an
   76  * alternative.
   77  */
   78 #undef __FreeBSD_kernel__
   79 #define __FreeBSD_kernel__
   80 
   81 #if defined(_KERNEL) || defined(IN_RTLD)
   82 #define P_OSREL_SIGWAIT                 700000
   83 #define P_OSREL_SIGSEGV                 700004
   84 #define P_OSREL_MAP_ANON                800104
   85 #define P_OSREL_MAP_FSTRICT             1100036
   86 #define P_OSREL_SHUTDOWN_ENOTCONN       1100077
   87 #define P_OSREL_MAP_GUARD               1200035
   88 #define P_OSREL_WRFSBASE                1200041
   89 #define P_OSREL_CK_CYLGRP               1200046
   90 #define P_OSREL_VMTOTAL64               1200054
   91 
   92 #define P_OSREL_MAJOR(x)                ((x) / 100000)
   93 #endif
   94 
   95 #ifndef LOCORE
   96 #include <sys/types.h>
   97 #endif
   98 
   99 /*
  100  * Machine-independent constants (some used in following include files).
  101  * Redefined constants are from POSIX 1003.1 limits file.
  102  *
  103  * MAXCOMLEN should be >= sizeof(ac_comm) (see <acct.h>)
  104  */
  105 #include <sys/syslimits.h>
  106 
  107 #define MAXCOMLEN       19              /* max command name remembered */
  108 #define MAXINTERP       PATH_MAX        /* max interpreter file name length */
  109 #define MAXLOGNAME      33              /* max login name length (incl. NUL) */
  110 #define MAXUPRC         CHILD_MAX       /* max simultaneous processes */
  111 #define NCARGS          ARG_MAX         /* max bytes for an exec function */
  112 #define NGROUPS         (NGROUPS_MAX+1) /* max number groups */
  113 #define NOFILE          OPEN_MAX        /* max open files per process */
  114 #define NOGROUP         65535           /* marker for empty group set member */
  115 #define MAXHOSTNAMELEN  256             /* max hostname size */
  116 #define SPECNAMELEN     63              /* max length of devicename */
  117 
  118 /* More types and definitions used throughout the kernel. */
  119 #ifdef _KERNEL
  120 #include <sys/cdefs.h>
  121 #include <sys/errno.h>
  122 #ifndef LOCORE
  123 #include <sys/time.h>
  124 #include <sys/priority.h>
  125 #endif
  126 
  127 #ifndef FALSE
  128 #define FALSE   0
  129 #endif
  130 #ifndef TRUE
  131 #define TRUE    1
  132 #endif
  133 #endif
  134 
  135 #ifndef _KERNEL
  136 /* Signals. */
  137 #include <sys/signal.h>
  138 #endif
  139 
  140 /* Machine type dependent parameters. */
  141 #include <machine/param.h>
  142 #ifndef _KERNEL
  143 #include <sys/limits.h>
  144 #endif
  145 
  146 #ifndef DEV_BSHIFT
  147 #define DEV_BSHIFT      9               /* log2(DEV_BSIZE) */
  148 #endif
  149 #define DEV_BSIZE       (1<<DEV_BSHIFT)
  150 
  151 #ifndef BLKDEV_IOSIZE
  152 #define BLKDEV_IOSIZE  PAGE_SIZE        /* default block device I/O size */
  153 #endif
  154 #ifndef DFLTPHYS
  155 #define DFLTPHYS        (64 * 1024)     /* default max raw I/O transfer size */
  156 #endif
  157 #ifndef MAXPHYS
  158 #define MAXPHYS         (128 * 1024)    /* max raw I/O transfer size */
  159 #endif
  160 #ifndef MAXDUMPPGS
  161 #define MAXDUMPPGS      (DFLTPHYS/PAGE_SIZE)
  162 #endif
  163 
  164 /*
  165  * Constants related to network buffer management.
  166  * MCLBYTES must be no larger than PAGE_SIZE.
  167  */
  168 #ifndef MSIZE
  169 #define MSIZE           256             /* size of an mbuf */
  170 #endif
  171 
  172 #ifndef MCLSHIFT
  173 #define MCLSHIFT        11              /* convert bytes to mbuf clusters */
  174 #endif  /* MCLSHIFT */
  175 
  176 #define MCLBYTES        (1 << MCLSHIFT) /* size of an mbuf cluster */
  177 
  178 #if PAGE_SIZE < 2048
  179 #define MJUMPAGESIZE    MCLBYTES
  180 #elif PAGE_SIZE <= 8192
  181 #define MJUMPAGESIZE    PAGE_SIZE
  182 #else
  183 #define MJUMPAGESIZE    (8 * 1024)
  184 #endif
  185 
  186 #define MJUM9BYTES      (9 * 1024)      /* jumbo cluster 9k */
  187 #define MJUM16BYTES     (16 * 1024)     /* jumbo cluster 16k */
  188 
  189 /*
  190  * Some macros for units conversion
  191  */
  192 
  193 /* clicks to bytes */
  194 #ifndef ctob
  195 #define ctob(x) ((x)<<PAGE_SHIFT)
  196 #endif
  197 
  198 /* bytes to clicks */
  199 #ifndef btoc
  200 #define btoc(x) (((vm_offset_t)(x)+PAGE_MASK)>>PAGE_SHIFT)
  201 #endif
  202 
  203 /*
  204  * btodb() is messy and perhaps slow because `bytes' may be an off_t.  We
  205  * want to shift an unsigned type to avoid sign extension and we don't
  206  * want to widen `bytes' unnecessarily.  Assume that the result fits in
  207  * a daddr_t.
  208  */
  209 #ifndef btodb
  210 #define btodb(bytes)                    /* calculates (bytes / DEV_BSIZE) */ \
  211         (sizeof (bytes) > sizeof(long) \
  212          ? (daddr_t)((unsigned long long)(bytes) >> DEV_BSHIFT) \
  213          : (daddr_t)((unsigned long)(bytes) >> DEV_BSHIFT))
  214 #endif
  215 
  216 #ifndef dbtob
  217 #define dbtob(db)                       /* calculates (db * DEV_BSIZE) */ \
  218         ((off_t)(db) << DEV_BSHIFT)
  219 #endif
  220 
  221 #define PRIMASK 0x0ff
  222 #define PCATCH  0x100           /* OR'd with pri for tsleep to check signals */
  223 #define PDROP   0x200   /* OR'd with pri to stop re-entry of interlock mutex */
  224 
  225 #define NZERO   0               /* default "nice" */
  226 
  227 #define NBBY    8               /* number of bits in a byte */
  228 #define NBPW    sizeof(int)     /* number of bytes per word (integer) */
  229 
  230 #define CMASK   022             /* default file mask: S_IWGRP|S_IWOTH */
  231 
  232 #define NODEV   (dev_t)(-1)     /* non-existent device */
  233 
  234 /*
  235  * File system parameters and macros.
  236  *
  237  * MAXBSIZE -   Filesystems are made out of blocks of at most MAXBSIZE bytes
  238  *              per block.  MAXBSIZE may be made larger without effecting
  239  *              any existing filesystems as long as it does not exceed MAXPHYS,
  240  *              and may be made smaller at the risk of not being able to use
  241  *              filesystems which require a block size exceeding MAXBSIZE.
  242  *
  243  * MAXBCACHEBUF - Maximum size of a buffer in the buffer cache.  This must
  244  *              be >= MAXBSIZE and can be set differently for different
  245  *              architectures by defining it in <machine/param.h>.
  246  *              Making this larger allows NFS to do larger reads/writes.
  247  *
  248  * BKVASIZE -   Nominal buffer space per buffer, in bytes.  BKVASIZE is the
  249  *              minimum KVM memory reservation the kernel is willing to make.
  250  *              Filesystems can of course request smaller chunks.  Actual
  251  *              backing memory uses a chunk size of a page (PAGE_SIZE).
  252  *              The default value here can be overridden on a per-architecture
  253  *              basis by defining it in <machine/param.h>.
  254  *
  255  *              If you make BKVASIZE too small you risk seriously fragmenting
  256  *              the buffer KVM map which may slow things down a bit.  If you
  257  *              make it too big the kernel will not be able to optimally use
  258  *              the KVM memory reserved for the buffer cache and will wind
  259  *              up with too-few buffers.
  260  *
  261  *              The default is 16384, roughly 2x the block size used by a
  262  *              normal UFS filesystem.
  263  */
  264 #define MAXBSIZE        65536   /* must be power of 2 */
  265 #ifndef MAXBCACHEBUF
  266 #define MAXBCACHEBUF    MAXBSIZE /* must be a power of 2 >= MAXBSIZE */
  267 #endif
  268 #ifndef BKVASIZE
  269 #define BKVASIZE        16384   /* must be power of 2 */
  270 #endif
  271 #define BKVAMASK        (BKVASIZE-1)
  272 
  273 /*
  274  * MAXPATHLEN defines the longest permissible path length after expanding
  275  * symbolic links. It is used to allocate a temporary buffer from the buffer
  276  * pool in which to do the name expansion, hence should be a power of two,
  277  * and must be less than or equal to MAXBSIZE.  MAXSYMLINKS defines the
  278  * maximum number of symbolic links that may be expanded in a path name.
  279  * It should be set high enough to allow all legitimate uses, but halt
  280  * infinite loops reasonably quickly.
  281  */
  282 #define MAXPATHLEN      PATH_MAX
  283 #define MAXSYMLINKS     32
  284 
  285 /* Bit map related macros. */
  286 #define setbit(a,i)     (((unsigned char *)(a))[(i)/NBBY] |= 1<<((i)%NBBY))
  287 #define clrbit(a,i)     (((unsigned char *)(a))[(i)/NBBY] &= ~(1<<((i)%NBBY)))
  288 #define isset(a,i)                                                      \
  289         (((const unsigned char *)(a))[(i)/NBBY] & (1<<((i)%NBBY)))
  290 #define isclr(a,i)                                                      \
  291         ((((const unsigned char *)(a))[(i)/NBBY] & (1<<((i)%NBBY))) == 0)
  292 
  293 /* Macros for counting and rounding. */
  294 #ifndef howmany
  295 #define howmany(x, y)   (((x)+((y)-1))/(y))
  296 #endif
  297 #define nitems(x)       (sizeof((x)) / sizeof((x)[0]))
  298 #define rounddown(x, y) (((x)/(y))*(y))
  299 #define rounddown2(x, y) ((x)&(~((y)-1)))          /* if y is power of two */
  300 #define roundup(x, y)   ((((x)+((y)-1))/(y))*(y))  /* to any y */
  301 #define roundup2(x, y)  (((x)+((y)-1))&(~((y)-1))) /* if y is powers of two */
  302 #define powerof2(x)     ((((x)-1)&(x))==0)
  303 
  304 /* Macros for min/max. */
  305 #define MIN(a,b) (((a)<(b))?(a):(b))
  306 #define MAX(a,b) (((a)>(b))?(a):(b))
  307 
  308 #ifdef _KERNEL
  309 /*
  310  * Basic byte order function prototypes for non-inline functions.
  311  */
  312 #ifndef LOCORE
  313 #ifndef _BYTEORDER_PROTOTYPED
  314 #define _BYTEORDER_PROTOTYPED
  315 __BEGIN_DECLS
  316 __uint32_t       htonl(__uint32_t);
  317 __uint16_t       htons(__uint16_t);
  318 __uint32_t       ntohl(__uint32_t);
  319 __uint16_t       ntohs(__uint16_t);
  320 __END_DECLS
  321 #endif
  322 #endif
  323 
  324 #ifndef _BYTEORDER_FUNC_DEFINED
  325 #define _BYTEORDER_FUNC_DEFINED
  326 #define htonl(x)        __htonl(x)
  327 #define htons(x)        __htons(x)
  328 #define ntohl(x)        __ntohl(x)
  329 #define ntohs(x)        __ntohs(x)
  330 #endif /* !_BYTEORDER_FUNC_DEFINED */
  331 #endif /* _KERNEL */
  332 
  333 /*
  334  * Scale factor for scaled integers used to count %cpu time and load avgs.
  335  *
  336  * The number of CPU `tick's that map to a unique `%age' can be expressed
  337  * by the formula (1 / (2 ^ (FSHIFT - 11))).  The maximum load average that
  338  * can be calculated (assuming 32 bits) can be closely approximated using
  339  * the formula (2 ^ (2 * (16 - FSHIFT))) for (FSHIFT < 15).
  340  *
  341  * For the scheduler to maintain a 1:1 mapping of CPU `tick' to `%age',
  342  * FSHIFT must be at least 11; this gives us a maximum load avg of ~1024.
  343  */
  344 #define FSHIFT  11              /* bits to right of fixed binary point */
  345 #define FSCALE  (1<<FSHIFT)
  346 
  347 #define dbtoc(db)                       /* calculates devblks to pages */ \
  348         ((db + (ctodb(1) - 1)) >> (PAGE_SHIFT - DEV_BSHIFT))
  349 
  350 #define ctodb(db)                       /* calculates pages to devblks */ \
  351         ((db) << (PAGE_SHIFT - DEV_BSHIFT))
  352 
  353 /*
  354  * Old spelling of __containerof().
  355  */
  356 #define member2struct(s, m, x)                                          \
  357         ((struct s *)(void *)((char *)(x) - offsetof(struct s, m)))
  358 
  359 /*
  360  * Access a variable length array that has been declared as a fixed
  361  * length array.
  362  */
  363 #define __PAST_END(array, offset) (((__typeof__(*(array)) *)(array))[offset])
  364 
  365 #endif  /* _SYS_PARAM_H_ */

Cache object: de7923f12a3649c62a4e98c77f1e274b


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.