drivers/staging/wilc1000/wilc_msgqueue.c

   1
   2 #include "wilc_msgqueue.h"
   3 #include <linux/spinlock.h>
   4 #include "linux_wlan_common.h"
   5 #include <linux/errno.h>
   6 #include <linux/slab.h>
   7
   8 /*!
   9  *  @author             syounan
  10  *  @date               1 Sep 2010
  11  *  @note               copied from FLO glue implementatuion
  12  *  @version            1.0
  13  */
  14 int wilc_mq_create(struct message_queue *pHandle)
  15 {
  16         spin_lock_init(&pHandle->strCriticalSection);
  17         sema_init(&pHandle->sem, 0);
  18         pHandle->pstrMessageList = NULL;
  19         pHandle->u32ReceiversCount = 0;
  20         pHandle->bExiting = false;
  21         return 0;
  22 }
  23
  24 /*!
  25  *  @author             syounan
  26  *  @date               1 Sep 2010
  27  *  @note               copied from FLO glue implementatuion
  28  *  @version            1.0
  29  */
  30 int wilc_mq_destroy(struct message_queue *pHandle)
  31 {
  32         pHandle->bExiting = true;
  33
  34         /* Release any waiting receiver thread. */
  35         while (pHandle->u32ReceiversCount > 0) {
  36                 up(&pHandle->sem);
  37                 pHandle->u32ReceiversCount--;
  38         }
  39
  40         while (pHandle->pstrMessageList) {
  41                 struct message *pstrMessge = pHandle->pstrMessageList->next;
  42
  43                 kfree(pHandle->pstrMessageList);
  44                 pHandle->pstrMessageList = pstrMessge;
  45         }
  46
  47         return 0;
  48 }
  49
  50 /*!
  51  *  @author             syounan
  52  *  @date               1 Sep 2010
  53  *  @note               copied from FLO glue implementatuion
  54  *  @version            1.0
  55  */
  56 int wilc_mq_send(struct message_queue *pHandle,
  57                  const void *pvSendBuffer, u32 u32SendBufferSize)
  58 {
  59         unsigned long flags;
  60         struct message *pstrMessage = NULL;
  61
  62         if ((!pHandle) || (u32SendBufferSize == 0) || (!pvSendBuffer)) {
  63                 PRINT_ER("pHandle or pvSendBuffer is null\n");
  64                 return -EFAULT;
  65         }
  66
  67         if (pHandle->bExiting) {
  68                 PRINT_ER("pHandle fail\n");
  69                 return -EFAULT;
  70         }
  71
  72         /* construct a new message */
  73         pstrMessage = kmalloc(sizeof(struct message), GFP_ATOMIC);
  74         if (!pstrMessage)
  75                 return -ENOMEM;
  76
  77         pstrMessage->len = u32SendBufferSize;
  78         pstrMessage->next = NULL;
  79         pstrMessage->buf = kmemdup(pvSendBuffer, u32SendBufferSize,
  80                                    GFP_ATOMIC);
  81         if (!pstrMessage->buf) {
  82                 kfree(pstrMessage);
  83                 return -ENOMEM;
  84         }
  85
  86         spin_lock_irqsave(&pHandle->strCriticalSection, flags);
  87
  88         /* add it to the message queue */
  89         if (!pHandle->pstrMessageList) {
  90                 pHandle->pstrMessageList  = pstrMessage;
  91         } else {
  92                 struct message *pstrTailMsg = pHandle->pstrMessageList;
  93
  94                 while (pstrTailMsg->next)
  95                         pstrTailMsg = pstrTailMsg->next;
  96
  97                 pstrTailMsg->next = pstrMessage;
  98         }
  99
 100         spin_unlock_irqrestore(&pHandle->strCriticalSection, flags);
 101
 102         up(&pHandle->sem);
 103
 104         return 0;
 105 }
 106
 107 /*!
 108  *  @author             syounan
 109  *  @date               1 Sep 2010
 110  *  @note               copied from FLO glue implementatuion
 111  *  @version            1.0
 112  */
 113 int wilc_mq_recv(struct message_queue *pHandle,
 114                  void *pvRecvBuffer, u32 u32RecvBufferSize,
 115                  u32 *pu32ReceivedLength)
 116 {
 117         struct message *pstrMessage;
 118         unsigned long flags;
 119
 120         if ((!pHandle) || (u32RecvBufferSize == 0)
 121             || (!pvRecvBuffer) || (!pu32ReceivedLength)) {
 122                 PRINT_ER("pHandle or pvRecvBuffer is null\n");
 123                 return -EINVAL;
 124         }
 125
 126         if (pHandle->bExiting) {
 127                 PRINT_ER("pHandle fail\n");
 128                 return -EFAULT;
 129         }
 130
 131         spin_lock_irqsave(&pHandle->strCriticalSection, flags);
 132         pHandle->u32ReceiversCount++;
 133         spin_unlock_irqrestore(&pHandle->strCriticalSection, flags);
 134
 135         down(&pHandle->sem);
 136         spin_lock_irqsave(&pHandle->strCriticalSection, flags);
 137
 138         pstrMessage = pHandle->pstrMessageList;
 139         if (!pstrMessage) {
 140                 spin_unlock_irqrestore(&pHandle->strCriticalSection, flags);
 141                 PRINT_ER("pstrMessage is null\n");
 142                 return -EFAULT;
 143         }
 144         /* check buffer size */
 145         if (u32RecvBufferSize < pstrMessage->len) {
 146                 spin_unlock_irqrestore(&pHandle->strCriticalSection, flags);
 147                 up(&pHandle->sem);
 148                 PRINT_ER("u32RecvBufferSize overflow\n");
 149                 return -EOVERFLOW;
 150         }
 151
 152         /* consume the message */
 153         pHandle->u32ReceiversCount--;
 154         memcpy(pvRecvBuffer, pstrMessage->buf, pstrMessage->len);
 155         *pu32ReceivedLength = pstrMessage->len;
 156
 157         pHandle->pstrMessageList = pstrMessage->next;
 158
 159         kfree(pstrMessage->buf);
 160         kfree(pstrMessage);
 161
 162         spin_unlock_irqrestore(&pHandle->strCriticalSection, flags);
 163
 164         return 0;
 165 }