sys/dev/md.h

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (c) 1995 Gordon W. Ross
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #ifndef _SYS_DEV_MD_H_
  29 #define _SYS_DEV_MD_H_
  30
  31 /*
  32  * Memory-disk ioctl functions:
  33  */
  34
  35 #include <sys/ioccom.h>
  36
  37 struct md_conf {
  38         void *md_addr;
  39         size_t  md_size;
  40         int     md_type;
  41 };
  42
  43 #define MD_GETCONF      _IOR('r', 0, struct md_conf)    /* get unit config */
  44 #define MD_SETCONF      _IOW('r', 1, struct md_conf)    /* set unit config */
  45
  46 /*
  47  * There are three configurations supported for each unit,
  48  * reflected in the value of the md_type field:
  49  */
  50 #define MD_UNCONFIGURED 0
  51 /*
  52  *     Not yet configured.  Open returns ENXIO.
  53  */
  54 #define MD_KMEM_FIXED   1
  55 /*
  56  *     Disk image resident in kernel (patched in or loaded).
  57  *     Requires that the function: md_set_kmem() is called to
  58  *     attach the (initialized) kernel memory to be used by the
  59  *     device.  It can be initialized by an "open hook" if this
  60  *     driver is compiled with the MD_OPEN_HOOK option.
  61  *     No attempt will ever be made to free this memory.
  62  */
  63 #define MD_KMEM_ALLOCATED 2
  64 /*
  65  *     Small, wired-down chunk of kernel memory obtained from
  66  *     kmem_alloc().  The allocation is performed by an ioctl
  67  *     call on the raw partition.
  68  */
  69 #define MD_UMEM_SERVER 3
  70 /*
  71  *     Indirect access to user-space of a user-level server.
  72  *     (Like the MFS hack, but better! 8^)  Device operates
  73  *     only while the server has the raw partition open and
  74  *     continues to service I/O requests.  The process that
  75  *     does this setconf will become the I/O server.  This
  76  *     configuration type can be disabled using:
  77  *         options  MEMORY_DISK_SERVER=0
  78  */
  79
  80 #ifdef  _KERNEL
  81 /*
  82  * If the option MEMORY_DISK_HOOKS is on, then these functions are
  83  * called by the ramdisk driver to allow machine-dependent to
  84  * match/configure and/or load each ramdisk unit.
  85  */
  86 extern void md_attach_hook(int, struct md_conf *);
  87 extern void md_open_hook(int, struct md_conf *);
  88 extern void md_root_setconf(char *, size_t);
  89
  90 extern int md_is_root;
  91 #endif /* _KERNEL */
  92
  93 #endif /* _SYS_DEV_MD_H_ */