staging: visorchannelstub driver to provide channel support routines

The visorchannelstub module provides support routines for storing and
retrieving data from a channel.

Signed-off-by: Ken Cox <jkc@redhat.com>
Cc: Ben Romer <sparmaintainer@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ken Cox 2014-03-04 07:58:08 -06:00 committed by Greg Kroah-Hartman
parent 12e364b9f0
commit 7b2a2d8383
7 changed files with 425 additions and 0 deletions

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@ -12,5 +12,6 @@ if UNISYSSPAR
source "drivers/staging/unisys/visorutil/Kconfig" source "drivers/staging/unisys/visorutil/Kconfig"
source "drivers/staging/unisys/visorchannel/Kconfig" source "drivers/staging/unisys/visorchannel/Kconfig"
source "drivers/staging/unisys/visorchipset/Kconfig" source "drivers/staging/unisys/visorchipset/Kconfig"
source "drivers/staging/unisys/channels/Kconfig"
endif # UNISYSSPAR endif # UNISYSSPAR

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@ -4,4 +4,5 @@
obj-$(CONFIG_UNISYS_VISORUTIL) += visorutil/ obj-$(CONFIG_UNISYS_VISORUTIL) += visorutil/
obj-$(CONFIG_UNISYS_VISORCHANNEL) += visorchannel/ obj-$(CONFIG_UNISYS_VISORCHANNEL) += visorchannel/
obj-$(CONFIG_UNISYS_VISORCHIPSET) += visorchipset/ obj-$(CONFIG_UNISYS_VISORCHIPSET) += visorchipset/
obj-$(CONFIG_UNISYS_CHANNELSTUB) += channels/

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@ -0,0 +1,10 @@
#
# Unisys channels configuration
#
config UNISYS_CHANNELSTUB
tristate "Unisys channelstub driver"
depends on UNISYSSPAR
---help---
If you say Y here, you will enable the Unisys channels driver.

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@ -0,0 +1,13 @@
#
# Makefile for Unisys channelstub
#
obj-$(CONFIG_UNISYS_CHANNELSTUB) += visorchannelstub.o
visorchannelstub-y := channel.o chanstub.o
ccflags-y += -Idrivers/staging/unisys/include
ccflags-y += -Idrivers/staging/unisys/common-spar/include
ccflags-y += -Idrivers/staging/unisys/common-spar/include/channels
ccflags-y += -DCONFIG_SPAR_GUEST -DGUESTDRIVERBUILD -DNOAUTOVERSION

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@ -0,0 +1,307 @@
/* Copyright © 2010 - 2013 UNISYS CORPORATION
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for more
* details.
*/
#include <linux/kernel.h>
#ifdef CONFIG_MODVERSIONS
#include <config/modversions.h>
#endif
#include <linux/module.h>
#include <linux/init.h> /* for module_init and module_exit */
#include <linux/slab.h> /* for memcpy */
#include <linux/types.h>
/* Implementation of exported functions for Supervisor channels */
#include "channel.h"
/*
* Routine Description:
* Tries to insert the prebuilt signal pointed to by pSignal into the nth
* Queue of the Channel pointed to by pChannel
*
* Parameters:
* pChannel: (IN) points to the IO Channel
* Queue: (IN) nth Queue of the IO Channel
* pSignal: (IN) pointer to the signal
*
* Assumptions:
* - pChannel, Queue and pSignal are valid.
* - If insertion fails due to a full queue, the caller will determine the
* retry policy (e.g. wait & try again, report an error, etc.).
*
* Return value:
* 1 if the insertion succeeds, 0 if the queue was full.
*/
unsigned char
SignalInsert(pCHANNEL_HEADER pChannel, U32 Queue, void *pSignal)
{
void *psignal;
unsigned int head, tail;
pSIGNAL_QUEUE_HEADER pqhdr =
(pSIGNAL_QUEUE_HEADER) ((char *) pChannel +
pChannel->oChannelSpace) + Queue;
/* capture current head and tail */
head = pqhdr->Head;
tail = pqhdr->Tail;
/* queue is full if (head + 1) % n equals tail */
if (((head + 1) % pqhdr->MaxSignalSlots) == tail) {
pqhdr->NumOverflows++;
return 0;
}
/* increment the head index */
head = (head + 1) % pqhdr->MaxSignalSlots;
/* copy signal to the head location from the area pointed to
* by pSignal
*/
psignal =
(char *) pqhdr + pqhdr->oSignalBase + (head * pqhdr->SignalSize);
MEMCPY(psignal, pSignal, pqhdr->SignalSize);
VolatileBarrier();
pqhdr->Head = head;
pqhdr->NumSignalsSent++;
return 1;
}
EXPORT_SYMBOL_GPL(SignalInsert);
/*
* Routine Description:
* Removes one signal from Channel pChannel's nth Queue at the
* time of the call and copies it into the memory pointed to by
* pSignal.
*
* Parameters:
* pChannel: (IN) points to the IO Channel
* Queue: (IN) nth Queue of the IO Channel
* pSignal: (IN) pointer to where the signals are to be copied
*
* Assumptions:
* - pChannel and Queue are valid.
* - pSignal points to a memory area large enough to hold queue's SignalSize
*
* Return value:
* 1 if the removal succeeds, 0 if the queue was empty.
*/
unsigned char
SignalRemove(pCHANNEL_HEADER pChannel, U32 Queue, void *pSignal)
{
void *psource;
unsigned int head, tail;
pSIGNAL_QUEUE_HEADER pqhdr =
(pSIGNAL_QUEUE_HEADER) ((char *) pChannel +
pChannel->oChannelSpace) + Queue;
/* capture current head and tail */
head = pqhdr->Head;
tail = pqhdr->Tail;
/* queue is empty if the head index equals the tail index */
if (head == tail) {
pqhdr->NumEmptyCnt++;
return 0;
}
/* advance past the 'empty' front slot */
tail = (tail + 1) % pqhdr->MaxSignalSlots;
/* copy signal from tail location to the area pointed to by pSignal */
psource =
(char *) pqhdr + pqhdr->oSignalBase + (tail * pqhdr->SignalSize);
MEMCPY(pSignal, psource, pqhdr->SignalSize);
VolatileBarrier();
pqhdr->Tail = tail;
pqhdr->NumSignalsReceived++;
return 1;
}
EXPORT_SYMBOL_GPL(SignalRemove);
/*
* Routine Description:
* Removes all signals present in Channel pChannel's nth Queue at the
* time of the call and copies them into the memory pointed to by
* pSignal. Returns the # of signals copied as the value of the routine.
*
* Parameters:
* pChannel: (IN) points to the IO Channel
* Queue: (IN) nth Queue of the IO Channel
* pSignal: (IN) pointer to where the signals are to be copied
*
* Assumptions:
* - pChannel and Queue are valid.
* - pSignal points to a memory area large enough to hold Queue's MaxSignals
* # of signals, each of which is Queue's SignalSize.
*
* Return value:
* # of signals copied.
*/
unsigned int
SignalRemoveAll(pCHANNEL_HEADER pChannel, U32 Queue, void *pSignal)
{
void *psource;
unsigned int head, tail, signalCount = 0;
pSIGNAL_QUEUE_HEADER pqhdr =
(pSIGNAL_QUEUE_HEADER) ((char *) pChannel +
pChannel->oChannelSpace) + Queue;
/* capture current head and tail */
head = pqhdr->Head;
tail = pqhdr->Tail;
/* queue is empty if the head index equals the tail index */
if (head == tail)
return 0;
while (head != tail) {
/* advance past the 'empty' front slot */
tail = (tail + 1) % pqhdr->MaxSignalSlots;
/* copy signal from tail location to the area pointed
* to by pSignal
*/
psource =
(char *) pqhdr + pqhdr->oSignalBase +
(tail * pqhdr->SignalSize);
MEMCPY((char *) pSignal + (pqhdr->SignalSize * signalCount),
psource, pqhdr->SignalSize);
VolatileBarrier();
pqhdr->Tail = tail;
signalCount++;
pqhdr->NumSignalsReceived++;
}
return signalCount;
}
/*
* Routine Description:
* Copies one signal from channel pChannel's nth Queue at the given position
* at the time of the call into the memory pointed to by pSignal.
*
* Parameters:
* pChannel: (IN) points to the IO Channel
* Queue: (IN) nth Queue of the IO Channel
* Position: (IN) nth entry in Queue of the IO Channel
* pSignal: (IN) pointer to where the signals are to be copied
*
* Assumptions:
* - pChannel and Queue are valid.
* - pSignal points to a memory area large enough to hold queue's SignalSize
*
* Return value:
* 1 if the copy succeeds, 0 if the queue was empty or Position was invalid.
*/
unsigned char
SignalPeek(pCHANNEL_HEADER pChannel, U32 Queue, U32 Position, void *pSignal)
{
void *psignal;
unsigned int head, tail;
pSIGNAL_QUEUE_HEADER pqhdr =
(pSIGNAL_QUEUE_HEADER) ((char *) pChannel +
pChannel->oChannelSpace) + Queue;
head = pqhdr->Head;
tail = pqhdr->Tail;
/* check if Position is out of range or queue is empty */
if (Position >= pqhdr->MaxSignalSlots || Position == tail
|| head == tail)
return 0;
/* check if Position is between tail and head */
if (head > tail) {
if (Position > head || Position < tail)
return 0;
} else if ((Position > head) && (Position < tail))
return 0;
/* copy signal from Position location to the area pointed to
* by pSignal
*/
psignal =
(char *) pqhdr + pqhdr->oSignalBase +
(Position * pqhdr->SignalSize);
MEMCPY(pSignal, psignal, pqhdr->SignalSize);
return 1;
}
/*
* Routine Description:
* Determine whether a signal queue is empty.
*
* Parameters:
* pChannel: (IN) points to the IO Channel
* Queue: (IN) nth Queue of the IO Channel
*
* Return value:
* 1 if the signal queue is empty, 0 otherwise.
*/
unsigned char
SignalQueueIsEmpty(pCHANNEL_HEADER pChannel, U32 Queue)
{
pSIGNAL_QUEUE_HEADER pqhdr =
(pSIGNAL_QUEUE_HEADER) ((char *) pChannel +
pChannel->oChannelSpace) + Queue;
return pqhdr->Head == pqhdr->Tail;
}
EXPORT_SYMBOL_GPL(SignalQueueIsEmpty);
/*
* Routine Description:
* Determine whether a signal queue is empty.
*
* Parameters:
* pChannel: (IN) points to the IO Channel
* Queue: (IN) nth Queue of the IO Channel
*
* Return value:
* 1 if the signal queue has 1 element, 0 otherwise.
*/
unsigned char
SignalQueueHasOneElement(pCHANNEL_HEADER pChannel, U32 Queue)
{
pSIGNAL_QUEUE_HEADER pqhdr =
(pSIGNAL_QUEUE_HEADER) ((char *) pChannel +
pChannel->oChannelSpace) + Queue;
return ((pqhdr->Tail + 1) % pqhdr->MaxSignalSlots) == pqhdr->Head;
}
/*
* Routine Description:
* Determine whether a signal queue is full.
*
* Parameters:
* pChannel: (IN) points to the IO Channel
* Queue: (IN) nth Queue of the IO Channel
*
* Return value:
* 1 if the signal queue is full, 0 otherwise.
*/
unsigned char
SignalQueueIsFull(pCHANNEL_HEADER pChannel, U32 Queue)
{
pSIGNAL_QUEUE_HEADER pqhdr =
(pSIGNAL_QUEUE_HEADER) ((char *) pChannel +
pChannel->oChannelSpace) + Queue;
return ((pqhdr->Head + 1) % pqhdr->MaxSignalSlots) == pqhdr->Tail;
}

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/* Copyright © 2010 - 2013 UNISYS CORPORATION
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for more
* details.
*/
#define EXPORT_SYMTAB
#include <linux/kernel.h>
#ifdef CONFIG_MODVERSIONS
#include <config/modversions.h>
#endif
#include <linux/module.h>
#include <linux/init.h> /* for module_init and module_exit */
#include <linux/slab.h> /* for memcpy */
#include <linux/types.h>
#include "channel.h"
#include "chanstub.h"
#include "version.h"
__init int
channel_mod_init(void)
{
return 0;
}
__exit void
channel_mod_exit(void)
{
}
unsigned char
SignalInsert_withLock(pCHANNEL_HEADER pChannel, U32 Queue,
void *pSignal, spinlock_t *lock)
{
unsigned char result;
unsigned long flags;
spin_lock_irqsave(lock, flags);
result = SignalInsert(pChannel, Queue, pSignal);
spin_unlock_irqrestore(lock, flags);
return result;
}
unsigned char
SignalRemove_withLock(pCHANNEL_HEADER pChannel, U32 Queue,
void *pSignal, spinlock_t *lock)
{
unsigned char result;
spin_lock(lock);
result = SignalRemove(pChannel, Queue, pSignal);
spin_unlock(lock);
return result;
}
module_init(channel_mod_init);
module_exit(channel_mod_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Bryan Glaudel");
MODULE_ALIAS("uischan");
/* this is extracted during depmod and kept in modules.dep */

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@ -0,0 +1,23 @@
/* Copyright © 2010 - 2013 UNISYS CORPORATION
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for more
* details.
*/
#ifndef __CHANSTUB_H__
#define __CHANSTUB_H__
unsigned char SignalInsert_withLock(pCHANNEL_HEADER pChannel, U32 Queue,
void *pSignal, spinlock_t *lock);
unsigned char SignalRemove_withLock(pCHANNEL_HEADER pChannel, U32 Queue,
void *pSignal, spinlock_t *lock);
#endif