path: root/drivers/char/ipmi/ipmi_devintf.c

/*
 * ipmi_devintf.c
 *
 * Linux device interface for the IPMI message handler.
 *
 * Author: MontaVista Software, Inc.
 *         Corey Minyard <minyard@mvista.com>
 *         source@mvista.com
 *
 * Copyright 2002 MontaVista Software Inc.
 *
 *  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 SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
 *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 *  OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 *  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 *  TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
 *  USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/errno.h>
#include <asm/system.h>
#include <linux/poll.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/ipmi.h>
#include <linux/mutex.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/compat.h>
#include <linux/smp_lock.h>

struct ipmi_file_private
{
	ipmi_user_t          user;
	spinlock_t           recv_msg_lock;
	struct list_head     recv_msgs;
	struct file          *file;
	struct fasync_struct *fasync_queue;
	wait_queue_head_t    wait;
	struct mutex	     recv_mutex;
	int                  default_retries;
	unsigned int         default_retry_time_ms;
};

static void file_receive_handler(struct ipmi_recv_msg *msg,
				 void                 *handler_data)
{
	struct ipmi_file_private *priv = handler_data;
	int                      was_empty;
	unsigned long            flags;

	spin_lock_irqsave(&(priv->recv_msg_lock), flags);

	was_empty = list_empty(&(priv->recv_msgs));
	list_add_tail(&(msg->link), &(priv->recv_msgs));

	if (was_empty) {
		wake_up_interruptible(&priv->wait);
		kill_fasync(&priv->fasync_queue, SIGIO, POLL_IN);
	}

	spin_unlock_irqrestore(&(priv->recv_msg_lock), flags);
}

static unsigned int ipmi_poll(struct file *file, poll_table *wait)
{
	struct ipmi_file_private *priv = file->private_data;
	unsigned int             mask = 0;
	unsigned long            flags;

	poll_wait(file, &priv->wait, wait);

	spin_lock_irqsave(&priv->recv_msg_lock, flags);

	if (!list_empty(&(priv->recv_msgs)))
		mask |= (POLLIN | POLLRDNORM);

	spin_unlock_irqrestore(&priv->recv_msg_lock, flags);

	return mask;
}

static int ipmi_fasync(int fd, struct file *file, int on)
{
	struct ipmi_file_private *priv = file->private_data;
	int                      result;

	lock_kernel(); /* could race against open() otherwise */
	result = fasync_helper(fd, file, on, &priv->fasync_queue);
	unlock_kernel();

	return (result);
}

static struct ipmi_user_hndl ipmi_hndlrs =
{
	.ipmi_recv_hndl	= file_receive_handler,
};

static int ipmi_open(struct inode *inode, struct file *file)
{
	int                      if_num = iminor(inode);
	int                      rv;
	struct ipmi_file_private *priv;


	priv = kmalloc(sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	lock_kernel();
	priv->file = file;

	rv = ipmi_create_user(if_num,
			      &ipmi_hndlrs,
			      priv,
			      &(priv->user));
	if (rv) {
		kfree(priv);
		goto out;
	}

	file->private_data = priv;

	spin_lock_init(&(priv->recv_msg_lock));
	INIT_LIST_HEAD(&(priv->recv_msgs));
	init_waitqueue_head(&priv->wait);
	priv->fasync_queue = NULL;
	mutex_init(&priv->recv_mutex);

	/* Use the low-level defaults. */
	priv->default_retries = -1;
	priv->default_retry_time_ms = 0;

out:
	unlock_kernel();
	return rv;
}

static int ipmi_release(struct inode *inode, struct file *file)
{
	struct ipmi_file_private *priv = file->private_data;
	int                      rv;

	rv = ipmi_destroy_user(priv->user);
	if (rv)
		return rv;

	/* FIXME - free the messages in the list. */
	kfree(priv);

	return 0;
}

static int handle_send_req(ipmi_user_t     user,
			   struct ipmi_req *req,
			   int             retries,
			   unsigned int    retry_time_ms)
{
	int              rv;
	struct ipmi_addr addr;
	struct kernel_ipmi_msg msg;

	if (req->addr_len > sizeof(struct ipmi_addr))