sys/sys/param.h

   1 /*-
   2  * Copyright (c) 1982, 1986, 1989, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  * (c) UNIX System Laboratories, Inc.
   5  * All or some portions of this file are derived from material licensed
   6  * to the University of California by American Telephone and Telegraph
   7  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
   8  * the permission of UNIX System Laboratories, Inc.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  *      @(#)param.h     8.3 (Berkeley) 4/4/95
  35  * $FreeBSD: src/sys/sys/param.h,v 1.61.2.38 2003/05/22 17:12:01 fjoe Exp $
  36  */
  37
  38 #ifndef _SYS_PARAM_H_
  39 #define _SYS_PARAM_H_
  40
  41 #define BSD     200708          /* XXX kern.osrevision */
  42 #define BSD4_3  1               /* XXX obsolete */
  43 #define BSD4_4  1               /* XXX obsolete */
  44
  45 /*
  46  * __DragonFly_version number.  The number doesn't really meaningfully
  47  * translate to a version number.
  48  *
  49  * 170000 - base development version after 1.6 branch
  50  * 170001 - base development version before 1.8 branch
  51  * 190000 - base development version after 1.8 branch
  52  * 195000 - base development version after 1.10 branch
  53  * 197500 - base development version before 1.12 branch
  54  * 197600 - 1.12 branch
  55  * 197700 - base development version after 1.12 branch
  56  * 199900 - base development version before 2.0 branch
  57  * 200000 - 2.0 branch
  58  * 200100 - base development version after 2.0 branch
  59  * 200101 - lchflags syscall
  60  * 200200 - 2.2 branch
  61  * 200201 - base development version after 2.2 branch
  62  * 200202 - major changes to libc
  63  * 200203 - introduce PCI domain
  64  * 200204 - suser() & suser_cred() removal
  65  * 200205 - devfs import
  66  * 200206 - *sleep() renames
  67  * 200400 - 2.4 release
  68  * 200500 - 2.5 master
  69  * 200600 - 2.6 release
  70  * 200700 - 2.7 master
  71  * 200800 - 2.8 release                 October 2010
  72  * 200900 - 2.9 master
  73  * 200901 - prototype changes for alphasort(3) and scandir(3)
  74  * 200902 - Xerox NS protocol removal
  75  * 201000 - 2.10 release
  76  * 201100 - 2.11 master
  77  * 201200 - 2.12 release
  78  * 201300 - 2.13 master
  79  * 201301 - header rename: <vfs/gnu/ext2fs/...> -> <gnu/vfs/ext2fs/...>
  80  * 201302 - header <crypt.h> is gone
  81  * 201303 - <netatalk/...> and <netproto/atalk/...> are gone
  82  * 201304 - Added wcscasecmp, wcsncasecmp to libc
  83  * 201305 - Sync libm with NetBSD-current libm (new functions added)
  84  * 201306 - Sync libm with FreeBSD-current libm (~50 new functions)
  85  * 300000 - 3.0 release
  86  * 300100 - 3.1 master
  87  * 300101 - i4b (ISDN) removal
  88  * 300102 - <sys/ata.h> is now just a link of <sys/nata.h>
  89  * 300103 - if SIG_IGN is set on SIGCHLD, do not keep zombie children
  90  * 300200 - 3.2 release
  91  * 300300 - 3.3 master
  92  * 300301 - Add eaccess syscall
  93  * 300302 - fpsave changes - ucontext_t, mcontext_t, sigcontext, sigframe
  94  * 300303 - Demarcation of old m4/flex with new m4/flex
  95  * 300304 - Update to dialog-1.2-20121230
  96  * 300400 - 3.4 release
  97  * 300500 - 3.5 master
  98  * 300501 - Convert libm to FreeBSD's version
  99  * 300502 - GEM and i915 KMS support in kernel
 100  * 300503 - Upgrade libiconv, locales, and associated libc functions
 101  * 300600 - 3.6 release
 102  * 300700 - 3.7 master
 103  * 300701 - Relocate bus/smbus/smb.h to dev/smbus/smb/smb.h
 104  * 300702 - drm/i915 update
 105  * 300703 - Make usb4bsd default
 106  * 300704 - Removal of IPX, NCP and NWFS support
 107  * 300705 - Removal of ATM support.
 108  * 300800 - 3.8 release
 109  * 300900 - 3.9 master
 110  * 300901 - drm/i915 hardware context support added
 111  * 400000 - 4.0 release
 112  * 400100 - 4.1 development
 113  * 400101 - Removal of SCTP support.
 114  * 400102 - Sound system update from FreeBSD
 115  * 400103 - Milestone - availability of gcc50 in base
 116  * 400104 - struct lwp_params (a public struct) members renaming
 117  * 400105 - Switch to gcc50 as the primary compiler
 118  * 400106 - Added pipe2() system call
 119  * 400107 - Add futimens() and utimensat() syscalls
 120  * 400200 - 4.2 release
 121  * 400300 - 4.3 development
 122  * 400301 - posix compliant iconv (no const qualifier)
 123  * 400302 - Replacement of libm with OpenBSD's libm
 124  * 400303 - environ and __progname are no longer linkable symbols
 125  * 400304 - Activate symbol versioning for libc.so (still on version 8)
 126  * 400305 - Add accept4() system call
 127  * 400306 - Add libexecinfo to base
 128  * 400307 - drm/i915 kernel module renamed to i915.ko
 129  * 400308 - <malloc.h> removal
 130  * 400309 - Add lwp_setname() system call
 131  * 400400 - 4.4 release
 132  * 400500 - 4.5 development
 133  * 400501 - unionfs removal
 134  * 400502 - private libraries: ssh ldns edit ncurses
 135  */
 136 #undef __DragonFly_version
 137 #define __DragonFly_version 400502      /* propagated to newvers */
 138
 139 #include <sys/_null.h>
 140
 141 #ifndef LOCORE
 142 #include <sys/types.h>
 143 #endif
 144
 145 /*
 146  * Machine-independent constants (some used in following include files).
 147  * Redefined constants are from POSIX 1003.1 limits file.
 148  *
 149  * MAXCOMLEN should be >= sizeof(ac_comm) (see <acct.h>)
 150  * MAXLOGNAME should be == UT_NAMESIZE+1 (see <utmp.h>)
 151  */
 152 #include <sys/syslimits.h>
 153
 154 #define MAXCOMLEN       16              /* max command name remembered */
 155 #define MAXINTERP       32              /* max interpreter file name length */
 156 #define MAXLOGNAME      17              /* max login name length (incl. NUL) */
 157 #define MAXUPRC         CHILD_MAX       /* max simultaneous processes */
 158 #define NCARGS          ARG_MAX         /* max bytes for an exec function */
 159 #define NGROUPS         NGROUPS_MAX     /* max number groups */
 160 #define NOFILE          OPEN_MAX        /* max open files per process */
 161 #define NOGROUP         65535           /* marker for empty group set member */
 162 #define MAXHOSTNAMELEN  256             /* max hostname size */
 163
 164 /* More types and definitions used throughout the kernel. */
 165 #ifdef _KERNEL
 166 #include <sys/cdefs.h>
 167 #include <sys/errno.h>
 168 #include <sys/time.h>
 169
 170 #define FALSE   0
 171 #define TRUE    1
 172 #endif
 173
 174 #ifndef _KERNEL
 175 /* Signals. */
 176 #include <sys/select.h>
 177 #include <sys/signal.h>
 178 #endif
 179
 180 /* Machine type dependent parameters. */
 181 #include <machine/param.h>
 182 #ifndef _KERNEL
 183 #include <machine/limits.h>
 184 #endif
 185
 186 /*
 187  * WARNING! Max supported cpu's due to PWAKEUP_CPUMASK is 16384.
 188  */
 189 #define PCATCH          0x00000100      /* tsleep checks signals */
 190 #define PUSRFLAG1       0x00000200      /* Subsystem specific flag */
 191 #define PINTERLOCKED    0x00000400      /* Interlocked tsleep */
 192 #define PWAKEUP_CPUMASK 0x00003FFF      /* start cpu for chained wakeups */
 193 #define PWAKEUP_MYCPU   0x00004000      /* wakeup on current cpu only */
 194 #define PWAKEUP_ONE     0x00008000      /* argument to wakeup: only one */
 195 #define PDOMAIN_MASK    0xFFFF0000      /* address domains for wakeup */
 196 #define PDOMAIN_UMTX    0x00010000      /* independant domain for UMTX */
 197 #define PDOMAIN_XLOCK   0x00020000      /* independant domain for fifo_lock */
 198 #define PWAKEUP_ENCODE(domain, cpu)     ((domain) | (cpu))
 199 #define PWAKEUP_DECODE(domain)          ((domain) & PWAKEUP_CPUMASK)
 200
 201 #define NZERO   0               /* default "nice" */
 202
 203 #define NBPW    sizeof(int)     /* number of bytes per word (integer) */
 204
 205 #define CMASK   022             /* default file mask: S_IWGRP|S_IWOTH */
 206 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
 207 #define NOUDEV  (udev_t)(-1)    /* non-existent device */
 208 #define NOMAJ   256             /* non-existent device */
 209 #endif
 210
 211 #ifndef _KERNEL
 212 #define NODEV   (dev_t)(-1)     /* non-existent device */
 213 #endif
 214
 215 /*
 216  * cpu_mi_feature bits
 217  */
 218 #define CPU_MI_BZERONT  0x00000001
 219 #define CPU_MI_MONITOR  0x00000010
 220
 221 /*
 222  * File system parameters and macros.
 223  *
 224  * MAXBSIZE -   Filesystems are made out of blocks of at most MAXBSIZE bytes
 225  *              per block.  MAXBSIZE may be made larger without effecting
 226  *              any existing filesystems as long as it does not exceed MAXPHYS,
 227  *              and may be made smaller at the risk of not being able to use
 228  *              filesystems which require a block size exceeding MAXBSIZE.
 229  *
 230  * BKVASIZE -   Nominal buffer space per buffer, in bytes.  BKVASIZE is the
 231  *              minimum KVM memory reservation the kernel is willing to make.
 232  *              Filesystems can of course request smaller chunks.  Actual
 233  *              backing memory uses a chunk size of a page (PAGE_SIZE).
 234  *
 235  *              If you make BKVASIZE too small you risk seriously fragmenting
 236  *              the buffer KVM map which may slow things down a bit.  If you
 237  *              make it too big the kernel will not be able to optimally use
 238  *              the KVM memory reserved for the buffer cache and will wind
 239  *              up with too-few buffers.
 240  *
 241  *              By default we now use maximally-sized reservations.  But on
 242  *              32-bit machines we reduce this 16KB.  Maximally-sized
 243  *              reservations greatly reduces defragmentation and buffer_map
 244  *              messing around and is more SMP-friendly.
 245  */
 246 #define MAXBSIZE        65536           /* must be power of 2 */
 247 #ifndef BKVASIZE
 248 #define BKVASIZE        MAXBSIZE        /* must be power of 2 */
 249 #endif
 250
 251 #define BKVAMASK        (BKVASIZE-1)
 252 #define MAXFRAG         8
 253
 254 /*
 255  * MAXPATHLEN defines the longest permissible path length after expanding
 256  * symbolic links. It is used to allocate a temporary buffer from the buffer
 257  * pool in which to do the name expansion, hence should be a power of two,
 258  * and must be less than or equal to MAXBSIZE.  MAXSYMLINKS defines the
 259  * maximum number of symbolic links that may be expanded in a path name.
 260  * It should be set high enough to allow all legitimate uses, but halt
 261  * infinite loops reasonably quickly.
 262  */
 263 #define MAXPATHLEN      PATH_MAX
 264 #define MAXSYMLINKS     32
 265
 266 /* Bit map related macros. */
 267 #define setbit(a,i)     ((a)[(i)/NBBY] |= 1<<((i)%NBBY))
 268 #define clrbit(a,i)     ((a)[(i)/NBBY] &= ~(1<<((i)%NBBY)))
 269 #define isset(a,i)      ((a)[(i)/NBBY] & (1<<((i)%NBBY)))
 270 #define isclr(a,i)      (((a)[(i)/NBBY] & (1<<((i)%NBBY))) == 0)
 271
 272 /* Macros for counting and rounding. */
 273 #ifndef howmany
 274 #define howmany(x, y)   (((x)+((y)-1))/(y))
 275 #endif
 276 #define nitems(x)       (sizeof((x)) / sizeof((x)[0]))
 277 #define rounddown(x, y) (((x)/(y))*(y))
 278 #define rounddown2(x, y) ((x) & ~((y) - 1))        /* y power of two */
 279 #define roundup(x, y)   ((((x)+((y)-1))/(y))*(y))  /* to any y */
 280 #define roundup2(x, y)  (((x)+((y)-1))&(~((y)-1))) /* if y is powers of two */
 281 #define powerof2(x)     ((((x)-1)&(x))==0)
 282
 283 /*
 284  * VM objects can be larger than the virtual address space, make sure
 285  * we don't cut-off the mask.
 286  */
 287 #define trunc_page64(x)           ((x) & ~(int64_t)PAGE_MASK)
 288 #define round_page64(x)           (((x) + PAGE_MASK) & ~(int64_t)PAGE_MASK)
 289
 290 /* Macros for min/max. */
 291 #define MIN(a,b) (((a)<(b))?(a):(b))
 292 #define MAX(a,b) (((a)>(b))?(a):(b))
 293
 294 /* Macro for array size */
 295 #define NELEM(ary)      (sizeof(ary) / sizeof((ary)[0]))
 296
 297 /*
 298  * Constants for setting the parameters of the kernel memory allocator.
 299  *
 300  * 2 ** MINBUCKET is the smallest unit of memory that will be
 301  * allocated. It must be at least large enough to hold a pointer.
 302  *
 303  * Units of memory less or equal to MAXALLOCSAVE will permanently
 304  * allocate physical memory; requests for these size pieces of
 305  * memory are quite fast. Allocations greater than MAXALLOCSAVE must
 306  * always allocate and free physical memory; requests for these
 307  * size allocations should be done infrequently as they will be slow.
 308  *
 309  * Constraints: PAGE_SIZE <= MAXALLOCSAVE <= 2 ** (MINBUCKET + 14), and
 310  * MAXALLOCSIZE must be a power of two.
 311  */
 312 #define MINBUCKET       4               /* 4 => min allocation of 16 bytes */
 313 #define MAXALLOCSAVE    (2 * PAGE_SIZE)
 314
 315 /*
 316  * Scale factor for scaled integers used to count %cpu time and load avgs.
 317  *
 318  * The number of CPU `tick's that map to a unique `%age' can be expressed
 319  * by the formula (1 / (2 ^ (FSHIFT - 11))).  The maximum load average that
 320  * can be calculated (assuming 32 bits) can be closely approximated using
 321  * the formula (2 ^ (2 * (16 - FSHIFT))) for (FSHIFT < 15).
 322  *
 323  * For the scheduler to maintain a 1:1 mapping of CPU `tick' to `%age',
 324  * FSHIFT must be at least 11; this gives us a maximum load avg of ~1024.
 325  */
 326 #define FSHIFT  11              /* bits to right of fixed binary point */
 327 #define FSCALE  (1<<FSHIFT)
 328
 329 #define dbtoc(db)                       /* calculates devblks to pages */ \
 330         ((db + (ctodb(1) - 1)) >> (PAGE_SHIFT - DEV_BSHIFT))
 331
 332 #define ctodb(db)                       /* calculates pages to devblks */ \
 333         ((db) << (PAGE_SHIFT - DEV_BSHIFT))
 334
 335 #define MJUMPAGESIZE    PAGE_SIZE       /* jumbo cluster 4k */
 336 #define MJUM9BYTES      (9 * 1024)      /* jumbo cluster 9k */
 337 #define MJUM16BYTES     (16 * 1024)     /* jumbo cluster 16k */
 338
 339 /*
 340  * MBUF Management.
 341  *
 342  * Because many drivers can't deal with multiple DMA segments all mbufs
 343  * must avoid crossing a page boundary.  While we can accomodate mbufs
 344  * which are not a power-of-2 sized kmalloc() will only guarantee
 345  * non-crossing alignment if we use a power-of-2.  256 is no longer large
 346  * enough due to m_hdr and m_pkthdr bloat.
 347  *
 348  * MCLBYTES must be a power of 2 and is typically significantly larger
 349  * than MSIZE, sufficient to hold a standard-mtu packet.  2K is considered
 350  * reasonable.
 351  */
 352 #ifndef MSIZE
 353 #define MSIZE           512             /* size of an mbuf */
 354 #endif
 355
 356 #ifndef MCLSHIFT
 357 #define MCLSHIFT        11              /* convert bytes to m_buf clusters */
 358 #endif
 359 #define MCLBYTES        (1 << MCLSHIFT) /* size of an m_buf cluster */
 360 #define MCLOFSET        (MCLBYTES - 1)  /* offset within an m_buf cluster */
 361
 362 /*
 363  * Make this available for most of the kernel.  There were too many
 364  * things that included sys/systm.h just for panic().
 365  */
 366 #ifdef _KERNEL
 367 void    panic (const char *, ...) __dead2 __printflike(1, 2);
 368 #endif
 369
 370 #ifndef htonl
 371 #define htonl(x)        __htonl(x)
 372 #endif
 373 #ifndef htons
 374 #define htons(x)        __htons(x)
 375 #endif
 376 #ifndef ntohl
 377 #define ntohl(x)        __ntohl(x)
 378 #endif
 379 #ifndef ntohs
 380 #define ntohs(x)        __ntohs(x)
 381 #endif
 382
 383 /*
 384  * Access a variable length array that has been declared as a fixed
 385  * length array.
 386  */
 387 #define __PAST_END(array, offset) (((__typeof__(*(array)) *)(array))[offset])
 388
 389 #endif  /* _SYS_PARAM_H_ */