Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / scsi / arm / msgqueue.c

diff --git a/kernel/drivers/scsi/arm/msgqueue.c b/kernel/drivers/scsi/arm/msgqueue.c
new file mode 100644 (file)
index 0000000..7c95c75
--- /dev/null
+++ b/kernel/drivers/scsi/arm/msgqueue.c
@@ -0,0 +1,171 @@
+/*
+ *  linux/drivers/acorn/scsi/msgqueue.c
+ *
+ *  Copyright (C) 1997-1998 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  message queue handling
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/stddef.h>
+#include <linux/init.h>
+
+#include "msgqueue.h"
+
+/*
+ * Function: struct msgqueue_entry *mqe_alloc(MsgQueue_t *msgq)
+ * Purpose : Allocate a message queue entry
+ * Params  : msgq - message queue to claim entry for
+ * Returns : message queue entry or NULL.
+ */
+static struct msgqueue_entry *mqe_alloc(MsgQueue_t *msgq)
+{
+       struct msgqueue_entry *mq;
+
+       if ((mq = msgq->free) != NULL)
+               msgq->free = mq->next;
+
+       return mq;
+}
+
+/*
+ * Function: void mqe_free(MsgQueue_t *msgq, struct msgqueue_entry *mq)
+ * Purpose : free a message queue entry
+ * Params  : msgq - message queue to free entry from
+ *          mq   - message queue entry to free
+ */
+static void mqe_free(MsgQueue_t *msgq, struct msgqueue_entry *mq)
+{
+       if (mq) {
+               mq->next = msgq->free;
+               msgq->free = mq;
+       }
+}
+
+/*
+ * Function: void msgqueue_initialise(MsgQueue_t *msgq)
+ * Purpose : initialise a message queue
+ * Params  : msgq - queue to initialise
+ */
+void msgqueue_initialise(MsgQueue_t *msgq)
+{
+       int i;
+
+       msgq->qe = NULL;
+       msgq->free = &msgq->entries[0];
+
+       for (i = 0; i < NR_MESSAGES; i++)
+               msgq->entries[i].next = &msgq->entries[i + 1];
+
+       msgq->entries[NR_MESSAGES - 1].next = NULL;
+}
+
+
+/*
+ * Function: void msgqueue_free(MsgQueue_t *msgq)
+ * Purpose : free a queue
+ * Params  : msgq - queue to free
+ */
+void msgqueue_free(MsgQueue_t *msgq)
+{
+}
+
+/*
+ * Function: int msgqueue_msglength(MsgQueue_t *msgq)
+ * Purpose : calculate the total length of all messages on the message queue
+ * Params  : msgq - queue to examine
+ * Returns : number of bytes of messages in queue
+ */
+int msgqueue_msglength(MsgQueue_t *msgq)
+{
+       struct msgqueue_entry *mq = msgq->qe;
+       int length = 0;
+
+       for (mq = msgq->qe; mq; mq = mq->next)
+               length += mq->msg.length;
+
+       return length;
+}
+
+/*
+ * Function: struct message *msgqueue_getmsg(MsgQueue_t *msgq, int msgno)
+ * Purpose : return a message
+ * Params  : msgq   - queue to obtain message from
+ *        : msgno  - message number
+ * Returns : pointer to message string, or NULL
+ */
+struct message *msgqueue_getmsg(MsgQueue_t *msgq, int msgno)
+{
+       struct msgqueue_entry *mq;
+
+       for (mq = msgq->qe; mq && msgno; mq = mq->next, msgno--);
+
+       return mq ? &mq->msg : NULL;
+}
+
+/*
+ * Function: int msgqueue_addmsg(MsgQueue_t *msgq, int length, ...)
+ * Purpose : add a message onto a message queue
+ * Params  : msgq   - queue to add message on
+ *          length - length of message
+ *          ...    - message bytes
+ * Returns : != 0 if successful
+ */
+int msgqueue_addmsg(MsgQueue_t *msgq, int length, ...)
+{
+       struct msgqueue_entry *mq = mqe_alloc(msgq);
+       va_list ap;
+
+       if (mq) {
+               struct msgqueue_entry **mqp;
+               int i;
+
+               va_start(ap, length);
+               for (i = 0; i < length; i++)
+                       mq->msg.msg[i] = va_arg(ap, unsigned int);
+               va_end(ap);
+
+               mq->msg.length = length;
+               mq->msg.fifo = 0;
+               mq->next = NULL;
+
+               mqp = &msgq->qe;
+               while (*mqp)
+                       mqp = &(*mqp)->next;
+
+               *mqp = mq;
+       }
+
+       return mq != NULL;
+}
+
+/*
+ * Function: void msgqueue_flush(MsgQueue_t *msgq)
+ * Purpose : flush all messages from message queue
+ * Params  : msgq - queue to flush
+ */
+void msgqueue_flush(MsgQueue_t *msgq)
+{
+       struct msgqueue_entry *mq, *mqnext;
+
+       for (mq = msgq->qe; mq; mq = mqnext) {
+               mqnext = mq->next;
+               mqe_free(msgq, mq);
+       }
+       msgq->qe = NULL;
+}
+
+EXPORT_SYMBOL(msgqueue_initialise);
+EXPORT_SYMBOL(msgqueue_free);
+EXPORT_SYMBOL(msgqueue_msglength);
+EXPORT_SYMBOL(msgqueue_getmsg);
+EXPORT_SYMBOL(msgqueue_addmsg);
+EXPORT_SYMBOL(msgqueue_flush);
+
+MODULE_AUTHOR("Russell King");
+MODULE_DESCRIPTION("SCSI message queue handling");
+MODULE_LICENSE("GPL");