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/pipe.h

Version: -  FREEBSD  -  FREEBSD11  -  FREEBSD10  -  FREEBSD9  -  FREEBSD92  -  FREEBSD91  -  FREEBSD90  -  FREEBSD8  -  FREEBSD82  -  FREEBSD81  -  FREEBSD80  -  FREEBSD7  -  FREEBSD74  -  FREEBSD73  -  FREEBSD72  -  FREEBSD71  -  FREEBSD70  -  FREEBSD6  -  FREEBSD64  -  FREEBSD63  -  FREEBSD62  -  FREEBSD61  -  FREEBSD60  -  FREEBSD5  -  FREEBSD55  -  FREEBSD54  -  FREEBSD53  -  FREEBSD52  -  FREEBSD51  -  FREEBSD50  -  FREEBSD4  -  FREEBSD3  -  FREEBSD22  -  linux-2.6  -  linux-2.4.22  -  MK83  -  MK84  -  PLAN9  -  DFBSD  -  NETBSD  -  NETBSD5  -  NETBSD4  -  NETBSD3  -  NETBSD20  -  OPENBSD  -  xnu-517  -  xnu-792  -  xnu-792.6.70  -  xnu-1228  -  xnu-1456.1.26  -  xnu-1699.24.8  -  xnu-2050.18.24  -  OPENSOLARIS  -  minix-3-1-1 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * Copyright (c) 1996 John S. Dyson
    3  * All rights reserved.
    4  *
    5  * Redistribution and use in source and binary forms, with or without
    6  * modification, are permitted provided that the following conditions
    7  * are met:
    8  * 1. Redistributions of source code must retain the above copyright
    9  *    notice immediately at the beginning of the file, without modification,
   10  *    this list of conditions, and the following disclaimer.
   11  * 2. Redistributions in binary form must reproduce the above copyright
   12  *    notice, this list of conditions and the following disclaimer in the
   13  *    documentation and/or other materials provided with the distribution.
   14  * 3. Absolutely no warranty of function or purpose is made by the author
   15  *    John S. Dyson.
   16  * 4. This work was done expressly for inclusion into FreeBSD.  Other use
   17  *    is allowed if this notation is included.
   18  * 5. Modifications may be freely made to this file if the above conditions
   19  *    are met.
   20  *
   21  * $FreeBSD: src/sys/sys/pipe.h,v 1.28.2.1 2005/01/31 23:26:56 imp Exp $
   22  */
   23 
   24 #ifndef _SYS_PIPE_H_
   25 #define _SYS_PIPE_H_
   26 
   27 #ifndef _KERNEL
   28 #error "no user-servicable parts inside"
   29 #endif
   30 
   31 /*
   32  * Pipe buffer size, keep moderate in value, pipes take kva space.
   33  */
   34 #ifndef PIPE_SIZE
   35 #define PIPE_SIZE       16384
   36 #endif
   37 
   38 #ifndef BIG_PIPE_SIZE
   39 #define BIG_PIPE_SIZE   (64*1024)
   40 #endif
   41 
   42 #ifndef SMALL_PIPE_SIZE
   43 #define SMALL_PIPE_SIZE PAGE_SIZE
   44 #endif
   45 
   46 /*
   47  * PIPE_MINDIRECT MUST be smaller than PIPE_SIZE and MUST be bigger
   48  * than PIPE_BUF.
   49  */
   50 #ifndef PIPE_MINDIRECT
   51 #define PIPE_MINDIRECT  8192
   52 #endif
   53 
   54 #define PIPENPAGES      (BIG_PIPE_SIZE / PAGE_SIZE + 1)
   55 
   56 /*
   57  * See sys_pipe.c for info on what these limits mean. 
   58  */
   59 extern int      maxpipekva;
   60 
   61 /*
   62  * Pipe buffer information.
   63  * Separate in, out, cnt are used to simplify calculations.
   64  * Buffered write is active when the buffer.cnt field is set.
   65  */
   66 struct pipebuf {
   67         u_int   cnt;            /* number of chars currently in buffer */
   68         u_int   in;             /* in pointer */
   69         u_int   out;            /* out pointer */
   70         u_int   size;           /* size of buffer */
   71         caddr_t buffer;         /* kva of buffer */
   72 };
   73 
   74 /*
   75  * Information to support direct transfers between processes for pipes.
   76  */
   77 struct pipemapping {
   78         vm_size_t       cnt;            /* number of chars in buffer */
   79         vm_size_t       pos;            /* current position of transfer */
   80         int             npages;         /* number of pages */
   81         vm_page_t       ms[PIPENPAGES]; /* pages in source process */
   82 };
   83 
   84 /*
   85  * Bits in pipe_state.
   86  */
   87 #define PIPE_ASYNC      0x004   /* Async? I/O. */
   88 #define PIPE_WANTR      0x008   /* Reader wants some characters. */
   89 #define PIPE_WANTW      0x010   /* Writer wants space to put characters. */
   90 #define PIPE_WANT       0x020   /* Pipe is wanted to be run-down. */
   91 #define PIPE_SEL        0x040   /* Pipe has a select active. */
   92 #define PIPE_EOF        0x080   /* Pipe is in EOF condition. */
   93 #define PIPE_LOCKFL     0x100   /* Process has exclusive access to pointers/data. */
   94 #define PIPE_LWANT      0x200   /* Process wants exclusive access to pointers/data. */
   95 #define PIPE_DIRECTW    0x400   /* Pipe direct write active. */
   96 #define PIPE_DIRECTOK   0x800   /* Direct mode ok. */
   97 
   98 /*
   99  * Per-pipe data structure.
  100  * Two of these are linked together to produce bi-directional pipes.
  101  */
  102 struct pipe {
  103         struct  pipebuf pipe_buffer;    /* data storage */
  104         struct  pipemapping pipe_map;   /* pipe mapping for direct I/O */
  105         struct  selinfo pipe_sel;       /* for compat with select */
  106         struct  timespec pipe_atime;    /* time of last access */
  107         struct  timespec pipe_mtime;    /* time of last modify */
  108         struct  timespec pipe_ctime;    /* time of status change */
  109         struct  sigio *pipe_sigio;      /* information for async I/O */
  110         struct  pipe *pipe_peer;        /* link with other direction */
  111         struct  pipepair *pipe_pair;    /* container structure pointer */
  112         u_int   pipe_state;             /* pipe status info */
  113         int     pipe_busy;              /* busy flag, mostly to handle rundown sanely */
  114         int     pipe_present;           /* still present? */
  115 };
  116 
  117 /*
  118  * Container structure to hold the two pipe endpoints, mutex, and label
  119  * pointer.
  120  */
  121 struct pipepair {
  122         struct pipe     pp_rpipe;
  123         struct pipe     pp_wpipe;
  124         struct mtx      pp_mtx;
  125         struct label    *pp_label;
  126 };
  127 
  128 #define PIPE_MTX(pipe)          (&(pipe)->pipe_pair->pp_mtx)
  129 #define PIPE_LOCK(pipe)         mtx_lock(PIPE_MTX(pipe))
  130 #define PIPE_UNLOCK(pipe)       mtx_unlock(PIPE_MTX(pipe))
  131 #define PIPE_LOCK_ASSERT(pipe, type)  mtx_assert(PIPE_MTX(pipe), (type))
  132 
  133 
  134 #endif /* !_SYS_PIPE_H_ */

Cache object: 6cdce1ea703ba4ee9fcfa6e914b13690


[ 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.