sys/i386/isa/ccbque.h

   1 /*      $NetBSD$        */
   2 /*-
   3  * [NetBSD for NEC PC98 series]
   4  *  Copyright (c) 1994, 1995, 1996 NetBSD/pc98 porting staff.
   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  *  3. The name of the author may not be used to endorse or promote products
  16  *     derived from this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  21  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  22  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  23  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  24  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  26  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  27  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  28  * POSSIBILITY OF SUCH DAMAGE.
  29  *
  30  * $FreeBSD$
  31  */
  32 /*
  33  * Common command control queue funcs.
  34  * Written by N. Honda.
  35  */
  36
  37 #ifndef _CCBQUE_H_
  38 #define _CCBQUE_H_
  39
  40 #define CCB_MWANTED 0x01
  41
  42 /* (I)  structure and prototype */
  43 #define GENERIC_CCB_ASSERT(DEV, CCBTYPE)                                \
  44 TAILQ_HEAD(CCBTYPE##tab, CCBTYPE);                                      \
  45 struct CCBTYPE##que {                                                   \
  46         struct CCBTYPE##tab CCBTYPE##tab;                               \
  47         int count;                                                      \
  48         int maxccb;                                                     \
  49         u_int flags;                                                    \
  50 };                                                                      \
  51                                                                         \
  52 void DEV##_init_ccbque(int);                                    \
  53 struct CCBTYPE *DEV##_get_ccb(void);                            \
  54 void DEV##_free_ccb(register struct CCBTYPE *);
  55
  56 /* (II)  static allocated memory */
  57 #define GENERIC_CCB_STATIC_ALLOC(DEV, CCBTYPE)                          \
  58 static struct CCBTYPE##que CCBTYPE##que;
  59
  60 /* (III)  functions */
  61 #define GENERIC_CCB(DEV, CCBTYPE, CHAIN)                                \
  62                                                                         \
  63 void                                                                    \
  64 DEV##_init_ccbque(count)                                                \
  65         int count;                                                      \
  66 {                                                                       \
  67         if (CCBTYPE##que.maxccb == 0)                                   \
  68                 TAILQ_INIT(&CCBTYPE##que.CCBTYPE##tab);                 \
  69         CCBTYPE##que.maxccb += count;                                   \
  70 }                                                                       \
  71                                                                         \
  72 struct CCBTYPE *                                                        \
  73 DEV##_get_ccb()                                                         \
  74 {                                                                       \
  75         register struct CCBTYPE *cb;                                    \
  76         int s = splcam();                                               \
  77                                                                         \
  78         if (CCBTYPE##que.count < CCBTYPE##que.maxccb)                   \
  79         {                                                               \
  80                 CCBTYPE##que.count ++;                                  \
  81                 cb = TAILQ_FIRST(&(CCBTYPE##que.CCBTYPE##tab));         \
  82                 if (cb != NULL)                                         \
  83                 {                                                       \
  84                         TAILQ_REMOVE(&CCBTYPE##que.CCBTYPE##tab, cb, CHAIN);\
  85                         goto out;                                       \
  86                 }                                                       \
  87                 else                                                    \
  88                 {                                                       \
  89                         cb = malloc(sizeof(*cb), M_DEVBUF, M_NOWAIT);   \
  90                         if (cb != NULL)                                 \
  91                         {                                               \
  92                                 bzero(cb, sizeof(*cb));                 \
  93                                 goto out;                               \
  94                         }                                               \
  95                 }                                                       \
  96                 CCBTYPE##que.count --;                                  \
  97         }                                                               \
  98                                                                         \
  99         cb = NULL;                                                      \
 100                                                                         \
 101 out:                                                                    \
 102         splx(s);                                                        \
 103         return cb;                                                      \
 104 }                                                                       \
 105                                                                         \
 106 void                                                                    \
 107 DEV##_free_ccb(cb)                                                      \
 108         register struct CCBTYPE *cb;                                    \
 109 {                                                                       \
 110         int s = splcam();                                               \
 111                                                                         \
 112         TAILQ_INSERT_TAIL(&CCBTYPE##que.CCBTYPE##tab, cb, CHAIN);       \
 113         CCBTYPE##que.count --;                                          \
 114                                                                         \
 115         if (CCBTYPE##que.flags & CCB_MWANTED)                           \
 116         {                                                               \
 117                 CCBTYPE##que.flags &= ~CCB_MWANTED;                     \
 118                 wakeup ((caddr_t) &CCBTYPE##que.count);                 \
 119         }                                                               \
 120         splx(s);                                                        \
 121 }
 122 #endif  /* !_CCBQUE_H_ */