sys/dev/dmover/dmover_process.c

   1 /*      $NetBSD: dmover_process.c,v 1.3 2007/10/08 16:18:03 ad Exp $    */
   2
   3 /*
   4  * Copyright (c) 2002 Wasabi Systems, Inc.
   5  * All rights reserved.
   6  *
   7  * Written by Jason R. Thorpe for Wasabi Systems, Inc.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. All advertising materials mentioning features or use of this software
  18  *    must display the following acknowledgement:
  19  *      This product includes software developed for the NetBSD Project by
  20  *      Wasabi Systems, Inc.
  21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
  22  *    or promote products derived from this software without specific prior
  23  *    written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
  26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
  29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  35  * POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38 /*
  39  * dmover_process.c: Processing engine for dmover-api.
  40  */
  41
  42 #include <sys/cdefs.h>
  43 __KERNEL_RCSID(0, "$NetBSD: dmover_process.c,v 1.3 2007/10/08 16:18:03 ad Exp $");
  44
  45 #include <sys/param.h>
  46 #include <sys/systm.h>
  47 #include <sys/proc.h>
  48 #include <sys/intr.h>
  49 #include <sys/simplelock.h>
  50
  51 #include <dev/dmover/dmovervar.h>
  52
  53 TAILQ_HEAD(, dmover_request) dmover_completed_q;
  54 struct simplelock dmover_completed_q_slock;     /* must be held at splbio */
  55
  56 void    *dmover_completed_si;
  57
  58 void    dmover_complete(void *);
  59
  60 /*
  61  * dmover_process_init:
  62  *
  63  *      Initialize the processing engine.
  64  */
  65 void
  66 dmover_process_initialize(void)
  67 {
  68
  69         TAILQ_INIT(&dmover_completed_q);
  70         simple_lock_init(&dmover_completed_q_slock);
  71
  72         dmover_completed_si = softint_establish(SOFTINT_CLOCK,
  73             dmover_complete, NULL);
  74 }
  75
  76 /*
  77  * dmover_process:      [client interface function]
  78  *
  79  *      Submit a tranform request for processing.
  80  */
  81 void
  82 dmover_process(struct dmover_request *dreq)
  83 {
  84         struct dmover_session *dses = dreq->dreq_session;
  85         struct dmover_assignment *das;
  86         struct dmover_backend *dmb;
  87         int s;
  88
  89 #ifdef DIAGNOSTIC
  90         if ((dreq->dreq_flags & DMOVER_REQ_WAIT) != 0 &&
  91             dreq->dreq_callback != NULL)
  92                 panic("dmover_process: WAIT used with callback");
  93 #endif
  94
  95         /* Clear unwanted flag bits. */
  96         dreq->dreq_flags &= __DMOVER_REQ_FLAGS_PRESERVE;
  97
  98         s = splbio();
  99
 100         /* XXXLOCK */
 101
 102         /* XXX Right now, the back-end is statically assigned. */
 103         das = &dses->__dses_assignment;
 104
 105         dmb = das->das_backend;
 106         dreq->dreq_assignment = das;
 107
 108         dmover_session_insque(dses, dreq);
 109         dmover_backend_insque(dmb, dreq);
 110
 111         /* XXXUNLOCK */
 112
 113         splx(s);
 114
 115         /* Kick the back-end into action. */
 116         (*dmb->dmb_process)(das->das_backend);
 117
 118         if (dreq->dreq_flags & DMOVER_REQ_WAIT) {
 119                 s = splbio();
 120                 /* XXXLOCK */
 121                 while ((dreq->dreq_flags & DMOVER_REQ_DONE) == 0)
 122                         (void) tsleep(dreq, PRIBIO, "dmover", 0);
 123                 /* XXXUNLOCK */
 124                 splx(s);
 125         }
 126 }
 127
 128 /*
 129  * dmover_done:         [back-end interface function]
 130  *
 131  *      Back-end notification that the dmover is done.
 132  */
 133 void
 134 dmover_done(struct dmover_request *dreq)
 135 {
 136         struct dmover_session *dses = dreq->dreq_session;
 137         int s;
 138
 139         s = splbio();
 140
 141         /* XXXLOCK */
 142
 143         dmover_session_remque(dses, dreq);
 144         /* backend has removed it from its queue */
 145
 146         /* XXXUNLOCK */
 147
 148         dreq->dreq_flags |= DMOVER_REQ_DONE;
 149         dreq->dreq_flags &= ~DMOVER_REQ_RUNNING;
 150         dreq->dreq_assignment = NULL;
 151
 152         if (dreq->dreq_callback != NULL) {
 153                 simple_lock(&dmover_completed_q_slock);
 154                 TAILQ_INSERT_TAIL(&dmover_completed_q, dreq, dreq_dmbq);
 155                 simple_unlock(&dmover_completed_q_slock);
 156                 softint_schedule(dmover_completed_si);
 157         } else if (dreq->dreq_flags & DMOVER_REQ_WAIT)
 158                 wakeup(dreq);
 159
 160         splx(s);
 161 }
 162
 163 /*
 164  * dmover_complete:
 165  *
 166  *      Complete a request by invoking the callback.
 167  */
 168 void
 169 dmover_complete(void *arg)
 170 {
 171         struct dmover_request *dreq;
 172         int s;
 173
 174         for (;;) {
 175                 s = splbio();
 176                 simple_lock(&dmover_completed_q_slock);
 177                 if ((dreq = TAILQ_FIRST(&dmover_completed_q)) != NULL)
 178                         TAILQ_REMOVE(&dmover_completed_q, dreq, dreq_dmbq);
 179                 simple_unlock(&dmover_completed_q_slock);
 180                 splx(s);
 181
 182                 if (dreq == NULL)
 183                         return;
 184
 185                 (*dreq->dreq_callback)(dreq);
 186         }
 187 }