drivers/block/ckrm-iostub.c

   1 /* ckrm-iostub.c - Stub file for ckrm_io module
   2  *
   3  * Copyright (C) Shailabh Nagar,  IBM Corp. 2004
   4  *
   5  * Latest version, more details at http://ckrm.sf.net
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  */
  13
  14 /* Changes
  15  *
  16  * 07 Aug 2004: Created
  17  *
  18  */
  19
  20 #include <linux/spinlock.h>
  21 #include <linux/module.h>
  22 #include <linux/ckrm-io.h>
  23
  24 static spinlock_t stub_lock = SPIN_LOCK_UNLOCKED;
  25
  26 static icls_tsk_t tskiclstub;
  27 static icls_ioprio_t tskiopriostub;
  28 static icls_tsk_t tskcfqprivstub;
  29
  30 void cki_cfq_set(icls_tsk_t tskicls, icls_ioprio_t tskioprio, icls_tsk_t tskcfqpriv)
  31 {
  32         spin_lock(&stub_lock);
  33         tskiclstub = tskicls;
  34         tskiopriostub = tskioprio;
  35         tskcfqprivstub = tskcfqpriv;
  36         spin_unlock(&stub_lock);
  37 }
  38
  39 void *cki_hash_key(struct task_struct *tsk)
  40 {
  41         void *ret;
  42         spin_lock(&stub_lock);
  43         if (tskiclstub)
  44                 ret = (*tskiclstub)(tsk);
  45         else
  46                 ret = (void *) tsk->tgid;
  47         spin_unlock(&stub_lock);
  48         return ret;
  49 }
  50
  51 int cki_ioprio(struct task_struct *tsk)
  52 {
  53         int ret;
  54         spin_lock(&stub_lock);
  55         if (tskiopriostub)
  56                 ret = (*tskiopriostub)(tsk);
  57         else
  58                 ret = tsk->ioprio;
  59         spin_unlock(&stub_lock);
  60         return ret;
  61 }
  62
  63 void *cki_cfqpriv(struct task_struct *tsk)
  64 {
  65         void *ret;
  66         spin_lock(&stub_lock);
  67         if (tskiclstub)
  68                 ret = (*tskcfqprivstub)(tsk);
  69         else
  70                 ret = NULL;
  71         spin_unlock(&stub_lock);
  72         return ret;
  73 }
  74
  75 EXPORT_SYMBOL(cki_cfq_set);
  76 EXPORT_SYMBOL(cki_hash_key);
  77 EXPORT_SYMBOL(cki_ioprio);
  78 EXPORT_SYMBOL(cki_cfqpriv);