1 files changed, 347 insertions, 0 deletions
diff --git a/drivers/staging/dgrp/dgrp_mon_ops.c b/drivers/staging/dgrp/dgrp_mon_ops.c
new file mode 100644
index 000000000000..4792d056a365
--- /dev/null
+++ b/drivers/staging/dgrp/dgrp_mon_ops.c
@@ -0,0 +1,347 @@
+/*****************************************************************************
+ *
+ * Copyright 1999 Digi International (www.digi.com)
+ *     James Puzzo <jamesp at digi dot com>
+ *
+ * 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, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; without even the
+ * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ */
+
+/*
+ *
+ *  Filename:
+ *
+ *     dgrp_mon_ops.c
+ *
+ *  Description:
+ *
+ *     Handle the file operations required for the "monitor" devices.
+ *     Includes those functions required to register the "mon" devices
+ *     in "/proc".
+ *
+ *  Author:
+ *
+ *     James A. Puzzo
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/tty.h>
+#include <linux/sched.h>
+#include <asm/unaligned.h>
+#include <linux/proc_fs.h>
+#include <linux/uaccess.h>
+
+#include "dgrp_common.h"
+
+/* File operation declarations */
+static int dgrp_mon_open(struct inode *, struct file *);
+static int dgrp_mon_release(struct inode *, struct file *);
+static ssize_t dgrp_mon_read(struct file *, char __user *, size_t, loff_t *);
+static long dgrp_mon_ioctl(struct file *file, unsigned int cmd,
+			   unsigned long arg);
+
+static const struct file_operations mon_ops = {
+	.owner   = THIS_MODULE,
+	.read    = dgrp_mon_read,
+	.unlocked_ioctl = dgrp_mon_ioctl,
+	.open    = dgrp_mon_open,
+	.release = dgrp_mon_release,
+};
+
+static struct inode_operations mon_inode_ops = {
+	.permission = dgrp_inode_permission
+};
+
+void dgrp_register_mon_hook(struct proc_dir_entry *de)
+{
+	struct nd_struct *node = de->data;
+
+	de->proc_iops = &mon_inode_ops;
+	de->proc_fops = &mon_ops;
+	node->nd_mon_de = de;
+	sema_init(&node->nd_mon_semaphore, 1);
+}
+
+/**
+ * dgrp_mon_open() -- open /proc/dgrp/ports device for a PortServer
+ * @inode: struct inode *
+ * @file: struct file *
+ *
+ * Open function to open the /proc/dgrp/ports device for a PortServer.
+ */
+static int dgrp_mon_open(struct inode *inode, struct file *file)
+{
+	struct nd_struct *nd;
+	struct proc_dir_entry *de;
+	struct timeval tv;
+	uint32_t time;
+	u8 *buf;
+	int rtn;
+
+	rtn = try_module_get(THIS_MODULE);
+	if (!rtn)
+		return -ENXIO;
+
+	rtn = 0;
+
+	if (!capable(CAP_SYS_ADMIN)) {
+		rtn = -EPERM;
+		goto done;
+	}
+
+	/*
+	 *  Make sure that the "private_data" field hasn't already been used.
+	 */
+	if (file->private_data) {
+		rtn = -EINVAL;
+		goto done;
+	}
+
+	/*
+	 *  Get the node pointer, and fail if it doesn't exist.
+	 */
+	de = PDE(inode);
+	if (!de) {
+		rtn = -ENXIO;
+		goto done;
+	}
+
+	nd = (struct nd_struct *)de->data;
+	if (!nd) {
+		rtn = -ENXIO;
+		goto done;
+	}
+
+	file->private_data = (void *) nd;
+
+	/*
+	 * Allocate the monitor buffer.
+	 */
+
+	/*
+	 *  Grab the MON lock.
+	 */
+	down(&nd->nd_mon_semaphore);
+
+	if (nd->nd_mon_buf) {
+		rtn = -EBUSY;
+		goto done_up;
+	}
+
+	nd->nd_mon_buf = kmalloc(MON_MAX, GFP_KERNEL);
+
+	if (!nd->nd_mon_buf) {
+		rtn = -ENOMEM;
+		goto done_up;
+	}
+
+	/*
+	 *  Enter an RPDUMP file header into the buffer.
+	 */
+
+	buf = nd->nd_mon_buf;
+
+	strcpy(buf, RPDUMP_MAGIC);
+	buf += strlen(buf) + 1;
+
+	do_gettimeofday(&tv);
+
+	/*
+	 *  tv.tv_sec might be a 64 bit quantity.  Pare
+	 *  it down to 32 bits before attempting to encode
+	 *  it.
+	 */
+	time = (uint32_t) (tv.tv_sec & 0xffffffff);
+
+	put_unaligned_be32(time, buf);
+	put_unaligned_be16(0, buf + 4);
+	buf += 6;
+
+	if (nd->nd_tx_module) {
+		buf[0] = RPDUMP_CLIENT;
+		put_unaligned_be32(0, buf + 1);
+		put_unaligned_be16(1, buf + 5);
+		buf[7] = 0xf0 + nd->nd_tx_module;
+		buf += 8;
+	}
+
+	if (nd->nd_rx_module) {
+		buf[0] = RPDUMP_SERVER;
+		put_unaligned_be32(0, buf + 1);
+		put_unaligned_be16(1, buf + 5);
+		buf[7] = 0xf0 + nd->nd_rx_module;
+		buf += 8;
+	}
+
+	nd->nd_mon_out = 0;
+	nd->nd_mon_in  = buf - nd->nd_mon_buf;
+	nd->nd_mon_lbolt = jiffies;
+
+done_up:
+	up(&nd->nd_mon_semaphore);
+
+done:
+	if (rtn)
+		module_put(THIS_MODULE);
+	return rtn;
+}
+
+
+/**
+ * dgrp_mon_release() - Close the MON device for a particular PortServer
+ * @inode: struct inode *
+ * @file: struct file *
+ */
+static int dgrp_mon_release(struct inode *inode, struct file *file)
+{
+	struct nd_struct *nd;
+
+	/*
+	 *  Get the node pointer, and quit if it doesn't exist.
+	 */
+	nd = (struct nd_struct *)(file->private_data);
+	if (!nd)
+		goto done;
+
+	/*
+	 *  Free the monitor buffer.
+	 */
+
+	down(&nd->nd_mon_semaphore);
+
+	kfree(nd->nd_mon_buf);
+	nd->nd_mon_buf = NULL;
+	nd->nd_mon_out = nd->nd_mon_in;
+
+	/*
+	 *  Wakeup any thread waiting for buffer space.
+	 */
+
+	if (nd->nd_mon_flag & MON_WAIT_SPACE) {
+		nd->nd_mon_flag &= ~MON_WAIT_SPACE;
+		wake_up_interruptible(&nd->nd_mon_wqueue);
+	}
+
+	up(&nd->nd_mon_semaphore);
+
+	/*
+	 *  Make sure there is no thread in the middle of writing a packet.
+	 */
+	down(&nd->nd_net_semaphore);
+	up(&nd->nd_net_semaphore);
+
+done:
+	module_put(THIS_MODULE);
+	file->private_data = NULL;
+	return 0;
+}
+
+/**
+ * dgrp_mon_read() -- Copy data from the monitoring buffer to the user
+ */
+static ssize_t dgrp_mon_read(struct file *file, char __user *buf, size_t count,
+			     loff_t *ppos)
+{
+	struct nd_struct *nd;
+	int r;
+	int offset = 0;
+	int res = 0;
+	ssize_t rtn;
+
+	/*
+	 *  Get the node pointer, and quit if it doesn't exist.
+	 */
+	nd = (struct nd_struct *)(file->private_data);
+	if (!nd)
+		return -ENXIO;
+
+	/*
+	 *  Wait for some data to appear in the buffer.
+	 */
+
+	down(&nd->nd_mon_semaphore);
+
+	for (;;) {
+		res = (nd->nd_mon_in - nd->nd_mon_out) & MON_MASK;
+
+		if (res)
+			break;
+
+		nd->nd_mon_flag |= MON_WAIT_DATA;
+
+		up(&nd->nd_mon_semaphore);
+
+		/*
+		 * Go to sleep waiting until the condition becomes true.
+		 */
+		rtn = wait_event_interruptible(nd->nd_mon_wqueue,
+					       ((nd->nd_mon_flag & MON_WAIT_DATA) == 0));
+
+		if (rtn)
+			return rtn;
+
+		down(&nd->nd_mon_semaphore);
+	}
+
+	/*
+	 *  Read whatever is there.
+	 */
+
+	if (res > count)
+		res = count;
+
+	r = MON_MAX - nd->nd_mon_out;
+
+	if (r <= res) {
+		rtn = copy_to_user((void __user *)buf,
+				   nd->nd_mon_buf + nd->nd_mon_out, r);
+		if (rtn) {
+			up(&nd->nd_mon_semaphore);
+			return -EFAULT;
+		}
+
+		nd->nd_mon_out = 0;
+		res -= r;
+		offset = r;
+	}
+
+	rtn = copy_to_user((void __user *) buf + offset,
+			   nd->nd_mon_buf + nd->nd_mon_out, res);
+	if (rtn) {
+		up(&nd->nd_mon_semaphore);
+		return -EFAULT;
+	}
+
+	nd->nd_mon_out += res;
+
+	*ppos += res;
+
+	up(&nd->nd_mon_semaphore);
+
+	/*
+	 *  Wakeup any thread waiting for buffer space.
+	 */
+
+	if (nd->nd_mon_flag & MON_WAIT_SPACE) {
+		nd->nd_mon_flag &= ~MON_WAIT_SPACE;
+		wake_up_interruptible(&nd->nd_mon_wqueue);
+	}
+
+	return res;
+}
+
+/*  ioctl is not valid on monitor device */
+static long dgrp_mon_ioctl(struct file *file, unsigned int cmd,
+			   unsigned long arg)
+{
+	return -EINVAL;
+}