drivers/staging/unisys/uislib/uisqueue.c

   1 /* uisqueue.c
   2  *
   3  * Copyright (C) 2010 - 2013 UNISYS CORPORATION
   4  * All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or (at
   9  * your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  14  * NON INFRINGEMENT.  See the GNU General Public License for more
  15  * details.
  16  */
  17
  18 /* @ALL_INSPECTED */
  19 #include <linux/kernel.h>
  20 #include <linux/module.h>
  21
  22 #include "uisutils.h"
  23
  24 #include "chanstub.h"
  25
  26 /* this is shorter than using __FILE__ (full path name) in
  27  * debug/info/error messages */
  28 #define CURRENT_FILE_PC UISLIB_PC_uisqueue_c
  29 #define __MYFILE__ "uisqueue.c"
  30
  31 #define CHECK_CACHE_ALIGN 0
  32
  33 /*****************************************************/
  34 /* Exported functions                                */
  35 /*****************************************************/
  36 unsigned long long
  37 uisqueue_interlocked_or(unsigned long long __iomem *tgt,
  38                        unsigned long long set)
  39 {
  40         unsigned long long i;
  41         unsigned long long j;
  42
  43         j = readq(tgt);
  44         do {
  45                 i = j;
  46                 j = cmpxchg((__force unsigned long long *)tgt, i, i | set);
  47
  48         } while (i != j);
  49
  50         return j;
  51 }
  52 EXPORT_SYMBOL_GPL(uisqueue_interlocked_or);
  53
  54 unsigned long long
  55 uisqueue_interlocked_and(unsigned long long __iomem *tgt,
  56                         unsigned long long set)
  57 {
  58         unsigned long long i;
  59         unsigned long long j;
  60
  61         j = readq(tgt);
  62         do {
  63                 i = j;
  64                 j = cmpxchg((__force unsigned long long *)tgt, i, i & set);
  65
  66         } while (i != j);
  67
  68         return j;
  69 }
  70 EXPORT_SYMBOL_GPL(uisqueue_interlocked_and);
  71
  72 static u8
  73 do_locked_client_insert(struct uisqueue_info *queueinfo,
  74                         unsigned int whichqueue,
  75                         void *pSignal,
  76                         spinlock_t *lock,
  77                         unsigned char issueInterruptIfEmpty,
  78                         u64 interruptHandle, u8 *channelId)
  79 {
  80         unsigned long flags;
  81         u8 rc = 0;
  82
  83         spin_lock_irqsave(lock, flags);
  84         if (!spar_channel_client_acquire_os(queueinfo->chan, channelId))
  85                 goto unlock;
  86         if (spar_signal_insert(queueinfo->chan, whichqueue, pSignal)) {
  87                 queueinfo->packets_sent++;
  88                 rc = 1;
  89         }
  90         spar_channel_client_release_os(queueinfo->chan, channelId);
  91 unlock:
  92         spin_unlock_irqrestore((spinlock_t *)lock, flags);
  93         return rc;
  94 }
  95
  96 int
  97 uisqueue_put_cmdrsp_with_lock_client(struct uisqueue_info *queueinfo,
  98                                      struct uiscmdrsp *cmdrsp,
  99                                      unsigned int whichqueue,
 100                                      void *insertlock,
 101                                      unsigned char issue_irq_if_empty,
 102                                      u64 irq_handle,
 103                                      char oktowait, u8 *channel_id)
 104 {
 105         while (!do_locked_client_insert(queueinfo, whichqueue, cmdrsp,
 106                                         (spinlock_t *) insertlock,
 107                                         issue_irq_if_empty,
 108                                         irq_handle, channel_id)) {
 109                 if (oktowait != OK_TO_WAIT) {
 110                         LOGERR("****FAILED visor_signal_insert failed; cannot wait; insert aborted\n");
 111                         return 0;       /* failed to queue */
 112                 }
 113                 /* try again */
 114                 LOGERR("****FAILED visor_signal_insert failed; waiting to try again\n");
 115                 set_current_state(TASK_INTERRUPTIBLE);
 116                 schedule_timeout(msecs_to_jiffies(10));
 117         }
 118         return 1;
 119 }
 120 EXPORT_SYMBOL_GPL(uisqueue_put_cmdrsp_with_lock_client);
 121
 122 /* uisqueue_get_cmdrsp gets the cmdrsp entry at the head of the queue
 123  * returns NULL if queue is empty */
 124 int
 125 uisqueue_get_cmdrsp(struct uisqueue_info *queueinfo,
 126                     void *cmdrsp, unsigned int whichqueue)
 127 {
 128         if (!spar_signal_remove(queueinfo->chan, whichqueue, cmdrsp))
 129                 return 0;
 130
 131         queueinfo->packets_received++;
 132
 133         return 1;               /* Success */
 134 }
 135 EXPORT_SYMBOL_GPL(uisqueue_get_cmdrsp);