[mirror_ubuntu-bionic-kernel.git] / drivers / staging / dgrp / dgrp_dpa_ops.c

/*
 *
 * 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_dpa_ops.c
 *
 *  Description:
 *
 *     Handle the file operations required for the "dpa" devices.
 *     Includes those functions required to register the "dpa" devices
 *     in "/proc".
 *
 *  Author:
 *
 *     James A. Puzzo
 *
 */

#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/tty.h>
#include <linux/poll.h>
#include <linux/cred.h>
#include <linux/sched.h>
#include <linux/ratelimit.h>
#include <asm/unaligned.h>

#include "dgrp_common.h"

/* File operation declarations */
static int dgrp_dpa_open(struct inode *, struct file *);
static int dgrp_dpa_release(struct inode *, struct file *);
static ssize_t dgrp_dpa_read(struct file *, char __user *, size_t, loff_t *);
static long dgrp_dpa_ioctl(struct file *file, unsigned int cmd,
			   unsigned long arg);
static unsigned int dgrp_dpa_select(struct file *, struct poll_table_struct *);

const struct file_operations dgrp_dpa_ops = {
	.owner   =  THIS_MODULE,
	.read    =  dgrp_dpa_read,
	.poll    =  dgrp_dpa_select,
	.unlocked_ioctl =  dgrp_dpa_ioctl,
	.open    =  dgrp_dpa_open,
	.release =  dgrp_dpa_release,
};

struct digi_node {
	uint	nd_state;		/* Node state: 1 = up, 0 = down. */
	uint	nd_chan_count;		/* Number of channels found */
	uint	nd_tx_byte;		/* Tx data count */
	uint	nd_rx_byte;		/* RX data count */
	u8	nd_ps_desc[MAX_DESC_LEN]; /* Description from PS */
};

#define DIGI_GETNODE      (('d'<<8) | 249)	/* get board info */


struct digi_chan {
	uint	ch_port;	/* Port number to get info on */
	uint	ch_open;	/* 1 if open, 0 if not */
	uint	ch_txcount;	/* TX data count  */
	uint	ch_rxcount;	/* RX data count  */
	uint	ch_s_brate;	/* Realport BRATE */
	uint	ch_s_estat;	/* Realport ELAST */
	uint	ch_s_cflag;	/* Realport CFLAG */
	uint	ch_s_iflag;	/* Realport IFLAG */
	uint	ch_s_oflag;	/* Realport OFLAG */
	uint	ch_s_xflag;	/* Realport XFLAG */
	uint	ch_s_mstat;	/* Realport MLAST */
};

#define DIGI_GETCHAN      (('d'<<8) | 248)	/* get channel info */


struct digi_vpd {
	int vpd_len;
	char vpd_data[VPDSIZE];
};

#define DIGI_GETVPD       (('d'<<8) | 246)	/* get VPD info */


struct digi_debug {
	int onoff;
	int port;
};

#define DIGI_SETDEBUG      (('d'<<8) | 247)	/* set debug info */


/*
 * dgrp_dpa_open -- open the DPA device for a particular PortServer
 */
static int dgrp_dpa_open(struct inode *inode, struct file *file)
{
	struct nd_struct *nd;
	int rtn = 0;

	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.
	 */
	nd = PDE_DATA(inode);
	if (!nd) {
		rtn = -ENXIO;
		goto done;
	}

	file->private_data = (void *) nd;

	/*
	 * Allocate the DPA buffer.
	 */

	if (nd->nd_dpa_buf) {
		rtn = -EBUSY;
	} else {
		nd->nd_dpa_buf = kmalloc(DPA_MAX, GFP_KERNEL);

		if (!nd->nd_dpa_buf) {
			rtn = -ENOMEM;
		} else {
			nd->nd_dpa_out = 0;
			nd->nd_dpa_in = 0;
			nd->nd_dpa_lbolt = jiffies;
		}
	}

done:

	if (rtn)
		module_put(THIS_MODULE);
	return rtn;
}

/*
 * dgrp_dpa_release -- close the DPA device for a particular PortServer
 */
static int dgrp_dpa_release(struct inode *inode, struct file *file)
{
	struct nd_struct *nd;
	u8 *buf;
	unsigned long lock_flags;

	/*
	 *  Get the node pointer, and quit if it doesn't exist.
	 */
	nd = (struct nd_struct *)(file->private_data);
	if (!nd)
		goto done;

	/*
	 *  Free the dpa buffer.
	 */

	spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags);

	buf = nd->nd_dpa_buf;

	nd->nd_dpa_buf = NULL;
	nd->nd_dpa_out = nd->nd_dpa_in;

	/*
	 *  Wakeup any thread waiting for buffer space.
	 */

	if (nd->nd_dpa_flag & DPA_WAIT_SPACE) {
		nd->nd_dpa_flag &= ~DPA_WAIT_SPACE;
		wake_up_interruptible(&nd->nd_dpa_wqueue);
	}

	spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);

	kfree(buf);

done:
	module_put(THIS_MODULE);
	file->private_data = NULL;
	return 0;
}

/*
 * dgrp_dpa_read
 *
 * Copy data from the monitoring buffer to the user, freeing space
 * in the monitoring buffer for more messages
 */
static ssize_t dgrp_dpa_read(struct file *file, char __user *buf, size_t count,
			     loff_t *ppos)
{
	struct nd_struct *nd;
	int n;
	int r;
	int offset = 0;
	int res = 0;
	ssize_t rtn;
	unsigned long lock_flags;

	/*
	 *  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.
	 */

	spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags);

	for (;;) {
		n = (nd->nd_dpa_in - nd->nd_dpa_out) & DPA_MASK;

		if (n != 0)
			break;

		nd->nd_dpa_flag |= DPA_WAIT_DATA;

		spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);

		/*
		 * Go to sleep waiting until the condition becomes true.
		 */
		rtn = wait_event_interruptible(nd->nd_dpa_wqueue,
			((nd->nd_dpa_flag & DPA_WAIT_DATA) == 0));

		if (rtn)
			return rtn;

		spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags);
	}

	/*
	 *  Read whatever is there.
	 */

	if (n > count)
		n = count;

	res = n;

	r = DPA_MAX - nd->nd_dpa_out;

	if (r <= n) {

		spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);
		rtn = copy_to_user((void __user *)buf,
				   nd->nd_dpa_buf + nd->nd_dpa_out, r);
		spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags);

		if (rtn) {
			rtn = -EFAULT;
			goto done;
		}

		nd->nd_dpa_out = 0;
		n -= r;
		offset = r;
	}

	spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);
	rtn = copy_to_user((void __user *)buf + offset,
			   nd->nd_dpa_buf + nd->nd_dpa_out, n);
	spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags);

	if (rtn) {
		rtn = -EFAULT;
		goto done;
	}

	nd->nd_dpa_out += n;

	*ppos += res;

	rtn = res;

	/*
	 *  Wakeup any thread waiting for buffer space.
	 */

	n = (nd->nd_dpa_in - nd->nd_dpa_out) & DPA_MASK;

	if (nd->nd_dpa_flag & DPA_WAIT_SPACE &&
	    (DPA_MAX - n) > DPA_HIGH_WATER) {
		nd->nd_dpa_flag &= ~DPA_WAIT_SPACE;
		wake_up_interruptible(&nd->nd_dpa_wqueue);
	}

 done:
	spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);
	return rtn;
}

static unsigned int dgrp_dpa_select(struct file *file,
				    struct poll_table_struct *table)
{
	unsigned int retval = 0;
	struct nd_struct *nd = file->private_data;

	if (nd->nd_dpa_out != nd->nd_dpa_in)
		retval |= POLLIN | POLLRDNORM; /* Conditionally readable */

	retval |= POLLOUT | POLLWRNORM;        /* Always writeable */

	return retval;
}

static long dgrp_dpa_ioctl(struct file *file, unsigned int cmd,
			   unsigned long arg)
{

	struct nd_struct  *nd;
	struct digi_chan getchan;
	struct digi_node getnode;
	struct ch_struct *ch;
	struct digi_debug setdebug;
	struct digi_vpd vpd;
	unsigned int port;
	void __user *uarg = (void __user *) arg;

	nd = file->private_data;

	switch (cmd) {
	case DIGI_GETCHAN:
		if (copy_from_user(&getchan, uarg, sizeof(struct digi_chan)))
			return -EFAULT;

		port = getchan.ch_port;

		if (port > nd->nd_chan_count)
			return -EINVAL;

		ch = nd->nd_chan + port;

		getchan.ch_open = (ch->ch_open_count > 0) ? 1 : 0;
		getchan.ch_txcount = ch->ch_txcount;
		getchan.ch_rxcount = ch->ch_rxcount;
		getchan.ch_s_brate = ch->ch_s_brate;
		getchan.ch_s_estat = ch->ch_s_elast;
		getchan.ch_s_cflag = ch->ch_s_cflag;
		getchan.ch_s_iflag = ch->ch_s_iflag;
		getchan.ch_s_oflag = ch->ch_s_oflag;
		getchan.ch_s_xflag = ch->ch_s_xflag;
		getchan.ch_s_mstat = ch->ch_s_mlast;

		if (copy_to_user(uarg, &getchan, sizeof(struct digi_chan)))
			return -EFAULT;
		break;


	case DIGI_GETNODE:
		getnode.nd_state = (nd->nd_state & NS_READY) ? 1 : 0;
		getnode.nd_chan_count = nd->nd_chan_count;
		getnode.nd_tx_byte = nd->nd_tx_byte;
		getnode.nd_rx_byte = nd->nd_rx_byte;

		memset(&getnode.nd_ps_desc, 0, MAX_DESC_LEN);
		strncpy(getnode.nd_ps_desc, nd->nd_ps_desc, MAX_DESC_LEN);

		if (copy_to_user(uarg, &getnode, sizeof(struct digi_node)))
			return -EFAULT;
		break;


	case DIGI_SETDEBUG:
		if (copy_from_user(&setdebug, uarg, sizeof(struct digi_debug)))
			return -EFAULT;

		nd->nd_dpa_debug = setdebug.onoff;
		nd->nd_dpa_port = setdebug.port;
		break;


	case DIGI_GETVPD:
		if (nd->nd_vpd_len > 0) {
			vpd.vpd_len = nd->nd_vpd_len;
			memcpy(&vpd.vpd_data, &nd->nd_vpd, nd->nd_vpd_len);
		} else {
			vpd.vpd_len = 0;
		}

		if (copy_to_user(uarg, &vpd, sizeof(struct digi_vpd)))
			return -EFAULT;
		break;
	}

	return 0;
}

/**
 * dgrp_dpa() -- send data to the device monitor queue
 * @nd: pointer to a node structure
 * @buf: buffer of data to copy to the monitoring buffer
 * @len: number of bytes to transfer to the buffer
 *
 * Called by the net device routines to send data to the device
 * monitor queue.  If the device monitor buffer is too full to
 * accept the data, it waits until the buffer is ready.
 */
static void dgrp_dpa(struct nd_struct *nd, u8 *buf, int nbuf)
{
	int n;
	int r;
	unsigned long lock_flags;

	/*
	 *  Grab DPA lock.
	 */
	spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags);

	/*
	 *  Loop while data remains.
	 */
	while (nbuf > 0 && nd->nd_dpa_buf != NULL) {

		n = (nd->nd_dpa_out - nd->nd_dpa_in - 1) & DPA_MASK;

		/*
		 * Enforce flow control on the DPA device.
		 */
		if (n < (DPA_MAX - DPA_HIGH_WATER))
			nd->nd_dpa_flag |= DPA_WAIT_SPACE;

		/*
		 * This should never happen, as the flow control above
		 * should have stopped things before they got to this point.
		 */
		if (n == 0) {
			spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);
			return;
		}

		/*
		 * Copy as much data as will fit.
		 */

		if (n > nbuf)
			n = nbuf;

		r = DPA_MAX - nd->nd_dpa_in;

		if (r <= n) {
			memcpy(nd->nd_dpa_buf + nd->nd_dpa_in, buf, r);

			n -= r;

			nd->nd_dpa_in = 0;

			buf += r;
			nbuf -= r;
		}

		memcpy(nd->nd_dpa_buf + nd->nd_dpa_in, buf, n);

		nd->nd_dpa_in += n;

		buf += n;
		nbuf -= n;

		if (nd->nd_dpa_in >= DPA_MAX)
			pr_info_ratelimited("%s - nd->nd_dpa_in (%i) >= DPA_MAX\n",
					    __func__, nd->nd_dpa_in);

		/*
		 *  Wakeup any thread waiting for data
		 */
		if (nd->nd_dpa_flag & DPA_WAIT_DATA) {
			nd->nd_dpa_flag &= ~DPA_WAIT_DATA;
			wake_up_interruptible(&nd->nd_dpa_wqueue);
		}
	}

	/*
	 *  Release the DPA lock.
	 */
	spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);
}

/**
 * dgrp_monitor_data() -- builds a DPA data packet
 * @nd: pointer to a node structure
 * @type: type of message to be logged in the DPA buffer
 * @buf: buffer of data to be logged in the DPA buffer
 * @size -- number of bytes in the "buf" buffer
 */
void dgrp_dpa_data(struct nd_struct *nd, int type, u8 *buf, int size)
{
	u8 header[5];

	header[0] = type;

	put_unaligned_be32(size, header + 1);

	dgrp_dpa(nd, header, sizeof(header));
	dgrp_dpa(nd, buf, size);
}
Commit	Line	Data
0b52b749 BP	1	/*
	2	*
	3	* Copyright 1999 Digi International (www.digi.com)
	4	* James Puzzo <jamesp at digi dot com>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2, or (at your option)
	9	* any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; without even the
	13	* implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
	14	* PURPOSE. See the GNU General Public License for more details.
	15	*
	16	*/
	17
	18	/*
	19	*
	20	* Filename:
	21	*
	22	* dgrp_dpa_ops.c
	23	*
	24	* Description:
	25	*
	26	* Handle the file operations required for the "dpa" devices.
	27	* Includes those functions required to register the "dpa" devices
	28	* in "/proc".
	29	*
	30	* Author:
	31	*
	32	* James A. Puzzo
	33	*
	34	*/
	35
	36	#include <linux/module.h>
	37	#include <linux/proc_fs.h>
	38	#include <linux/tty.h>
	39	#include <linux/poll.h>
	40	#include <linux/cred.h>
	41	#include <linux/sched.h>
	42	#include <linux/ratelimit.h>
	43	#include <asm/unaligned.h>
	44
	45	#include "dgrp_common.h"
	46
	47	/* File operation declarations */
	48	static int dgrp_dpa_open(struct inode , struct file );
	49	static int dgrp_dpa_release(struct inode , struct file );
	50	static ssize_t dgrp_dpa_read(struct file , char __user , size_t, loff_t *);
	51	static long dgrp_dpa_ioctl(struct file *file, unsigned int cmd,
	52	unsigned long arg);
	53	static unsigned int dgrp_dpa_select(struct file , struct poll_table_struct );
	54
af064cdd	55	const struct file_operations dgrp_dpa_ops = {
0b52b749 BP	56	.owner = THIS_MODULE,
	57	.read = dgrp_dpa_read,
	58	.poll = dgrp_dpa_select,
	59	.unlocked_ioctl = dgrp_dpa_ioctl,
	60	.open = dgrp_dpa_open,
	61	.release = dgrp_dpa_release,
	62	};
	63
0b52b749 BP	64	struct digi_node {
	65	uint nd_state; /* Node state: 1 = up, 0 = down. */
	66	uint nd_chan_count; /* Number of channels found */
	67	uint nd_tx_byte; /* Tx data count */
	68	uint nd_rx_byte; /* RX data count */
	69	u8 nd_ps_desc[MAX_DESC_LEN]; /* Description from PS */
	70	};
	71
	72	#define DIGI_GETNODE (('d'<<8) \| 249) /* get board info */
	73
	74
	75	struct digi_chan {
	76	uint ch_port; /* Port number to get info on */
	77	uint ch_open; /* 1 if open, 0 if not */
	78	uint ch_txcount; /* TX data count */
	79	uint ch_rxcount; /* RX data count */
	80	uint ch_s_brate; /* Realport BRATE */
	81	uint ch_s_estat; /* Realport ELAST */
	82	uint ch_s_cflag; /* Realport CFLAG */
	83	uint ch_s_iflag; /* Realport IFLAG */
	84	uint ch_s_oflag; /* Realport OFLAG */
	85	uint ch_s_xflag; /* Realport XFLAG */
	86	uint ch_s_mstat; /* Realport MLAST */
	87	};
	88
	89	#define DIGI_GETCHAN (('d'<<8) \| 248) /* get channel info */
	90
	91
	92	struct digi_vpd {
	93	int vpd_len;
	94	char vpd_data[VPDSIZE];
	95	};
	96
	97	#define DIGI_GETVPD (('d'<<8) \| 246) /* get VPD info */
	98
	99
	100	struct digi_debug {
	101	int onoff;
	102	int port;
	103	};
	104
	105	#define DIGI_SETDEBUG (('d'<<8) \| 247) /* set debug info */
	106
	107
0b52b749 BP	108	/*
	109	* dgrp_dpa_open -- open the DPA device for a particular PortServer
	110	*/
	111	static int dgrp_dpa_open(struct inode inode, struct file file)
	112	{
	113	struct nd_struct *nd;
	114	int rtn = 0;
	115
0b52b749 BP	116	rtn = try_module_get(THIS_MODULE);
	117	if (!rtn)
	118	return -ENXIO;
	119
	120	rtn = 0;
	121
	122	if (!capable(CAP_SYS_ADMIN)) {
	123	rtn = -EPERM;
	124	goto done;
	125	}
	126
	127	/*
	128	* Make sure that the "private_data" field hasn't already been used.
	129	*/
	130	if (file->private_data) {
	131	rtn = -EINVAL;
	132	goto done;
	133	}
	134
	135	/*
	136	* Get the node pointer, and fail if it doesn't exist.
	137	*/
d9dda78b	138	nd = PDE_DATA(inode);
0b52b749 BP	139	if (!nd) {
	140	rtn = -ENXIO;
	141	goto done;
	142	}
	143
	144	file->private_data = (void *) nd;
	145
	146	/*
	147	* Allocate the DPA buffer.
	148	*/
	149
	150	if (nd->nd_dpa_buf) {
	151	rtn = -EBUSY;
	152	} else {
	153	nd->nd_dpa_buf = kmalloc(DPA_MAX, GFP_KERNEL);
	154
	155	if (!nd->nd_dpa_buf) {
	156	rtn = -ENOMEM;
	157	} else {
	158	nd->nd_dpa_out = 0;
	159	nd->nd_dpa_in = 0;
	160	nd->nd_dpa_lbolt = jiffies;
	161	}
	162	}
	163
	164	done:
	165
	166	if (rtn)
	167	module_put(THIS_MODULE);
	168	return rtn;
	169	}
	170
	171	/*
	172	* dgrp_dpa_release -- close the DPA device for a particular PortServer
	173	*/
	174	static int dgrp_dpa_release(struct inode inode, struct file file)
	175	{
	176	struct nd_struct *nd;
	177	u8 *buf;
	178	unsigned long lock_flags;
	179
	180	/*
	181	* Get the node pointer, and quit if it doesn't exist.
	182	*/
	183	nd = (struct nd_struct *)(file->private_data);
	184	if (!nd)
	185	goto done;
	186
	187	/*
	188	* Free the dpa buffer.
	189	*/
	190
	191	spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags);
	192
	193	buf = nd->nd_dpa_buf;
	194
	195	nd->nd_dpa_buf = NULL;
	196	nd->nd_dpa_out = nd->nd_dpa_in;
	197
	198	/*
	199	* Wakeup any thread waiting for buffer space.
	200	*/
	201
	202	if (nd->nd_dpa_flag & DPA_WAIT_SPACE) {
203	nd->nd_dpa_flag &= ~DPA_WAIT_SPACE;
204	wake_up_interruptible(&nd->nd_dpa_wqueue);
205	}
206
207	spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);
208
209	kfree(buf);
210
211	done:
212	module_put(THIS_MODULE);
213	file->private_data = NULL;
214	return 0;
215	}
216
217	/*
218	* dgrp_dpa_read
219	*
220	* Copy data from the monitoring buffer to the user, freeing space
221	* in the monitoring buffer for more messages
222	*/
223	static ssize_t dgrp_dpa_read(struct file file, char __user buf, size_t count,
224	loff_t *ppos)
225	{
226	struct nd_struct *nd;
227	int n;
228	int r;
229	int offset = 0;
230	int res = 0;
231	ssize_t rtn;
232	unsigned long lock_flags;
233
234	/*
235	* Get the node pointer, and quit if it doesn't exist.
236	*/
237	nd = (struct nd_struct *)(file->private_data);
238	if (!nd)
239	return -ENXIO;
240
241	/*
242	* Wait for some data to appear in the buffer.
243	*/
244
245	spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags);
246
247	for (;;) {
248	n = (nd->nd_dpa_in - nd->nd_dpa_out) & DPA_MASK;
249
250	if (n != 0)
251	break;
252
253	nd->nd_dpa_flag \|= DPA_WAIT_DATA;
254
255	spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);
256
257	/*
258	* Go to sleep waiting until the condition becomes true.
259	*/
260	rtn = wait_event_interruptible(nd->nd_dpa_wqueue,
261	((nd->nd_dpa_flag & DPA_WAIT_DATA) == 0));
262
263	if (rtn)
264	return rtn;
265
266	spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags);
267	}
268
269	/*
270	* Read whatever is there.
271	*/
272
273	if (n > count)
274	n = count;
275
276	res = n;
277
278	r = DPA_MAX - nd->nd_dpa_out;
279
280	if (r <= n) {
281
282	spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);
283	rtn = copy_to_user((void __user *)buf,
284	nd->nd_dpa_buf + nd->nd_dpa_out, r);
285	spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags);
286
287	if (rtn) {
288	rtn = -EFAULT;
289	goto done;
290	}
291
292	nd->nd_dpa_out = 0;
293	n -= r;
294	offset = r;
295	}
296
297	spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);
298	rtn = copy_to_user((void __user *)buf + offset,
299	nd->nd_dpa_buf + nd->nd_dpa_out, n);
300	spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags);
301
302	if (rtn) {
303	rtn = -EFAULT;
304	goto done;
305	}
306
307	nd->nd_dpa_out += n;
308
309	*ppos += res;
310
311	rtn = res;
312
313	/*
314	* Wakeup any thread waiting for buffer space.
315	*/
316
317	n = (nd->nd_dpa_in - nd->nd_dpa_out) & DPA_MASK;
318
319	if (nd->nd_dpa_flag & DPA_WAIT_SPACE &&
320	(DPA_MAX - n) > DPA_HIGH_WATER) {
321	nd->nd_dpa_flag &= ~DPA_WAIT_SPACE;
322	wake_up_interruptible(&nd->nd_dpa_wqueue);
323	}
324
325	done:
326	spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);
327	return rtn;
328	}
329
330	static unsigned int dgrp_dpa_select(struct file *file,
331	struct poll_table_struct *table)
332	{
333	unsigned int retval = 0;
334	struct nd_struct *nd = file->private_data;
335
336	if (nd->nd_dpa_out != nd->nd_dpa_in)
337	retval \|= POLLIN \| POLLRDNORM; /* Conditionally readable */
338
339	retval \|= POLLOUT \| POLLWRNORM; /* Always writeable */
340
341	return retval;
342	}
343
344	static long dgrp_dpa_ioctl(struct file *file, unsigned int cmd,
345	unsigned long arg)
346	{
347
348	struct nd_struct *nd;
349	struct digi_chan getchan;
350	struct digi_node getnode;
351	struct ch_struct *ch;
352	struct digi_debug setdebug;
353	struct digi_vpd vpd;
354	unsigned int port;
355	void __user uarg = (void __user ) arg;
356
357	nd = file->private_data;
358
359	switch (cmd) {
360	case DIGI_GETCHAN:
361	if (copy_from_user(&getchan, uarg, sizeof(struct digi_chan)))
362	return -EFAULT;
363
364	port = getchan.ch_port;
365
720a9bec	366	if (port > nd->nd_chan_count)
0b52b749 BP	367	return -EINVAL;
	368
	369	ch = nd->nd_chan + port;
	370
	371	getchan.ch_open = (ch->ch_open_count > 0) ? 1 : 0;
	372	getchan.ch_txcount = ch->ch_txcount;
	373	getchan.ch_rxcount = ch->ch_rxcount;
	374	getchan.ch_s_brate = ch->ch_s_brate;
	375	getchan.ch_s_estat = ch->ch_s_elast;
	376	getchan.ch_s_cflag = ch->ch_s_cflag;
	377	getchan.ch_s_iflag = ch->ch_s_iflag;
	378	getchan.ch_s_oflag = ch->ch_s_oflag;
	379	getchan.ch_s_xflag = ch->ch_s_xflag;
	380	getchan.ch_s_mstat = ch->ch_s_mlast;
	381
	382	if (copy_to_user(uarg, &getchan, sizeof(struct digi_chan)))
	383	return -EFAULT;
	384	break;
	385
	386
	387	case DIGI_GETNODE:
	388	getnode.nd_state = (nd->nd_state & NS_READY) ? 1 : 0;
	389	getnode.nd_chan_count = nd->nd_chan_count;
	390	getnode.nd_tx_byte = nd->nd_tx_byte;
	391	getnode.nd_rx_byte = nd->nd_rx_byte;
	392
	393	memset(&getnode.nd_ps_desc, 0, MAX_DESC_LEN);
	394	strncpy(getnode.nd_ps_desc, nd->nd_ps_desc, MAX_DESC_LEN);
	395
	396	if (copy_to_user(uarg, &getnode, sizeof(struct digi_node)))
	397	return -EFAULT;
	398	break;
	399
	400
	401	case DIGI_SETDEBUG:
	402	if (copy_from_user(&setdebug, uarg, sizeof(struct digi_debug)))
	403	return -EFAULT;
	404
	405	nd->nd_dpa_debug = setdebug.onoff;
	406	nd->nd_dpa_port = setdebug.port;
	407	break;
	408
	409
	410	case DIGI_GETVPD:
	411	if (nd->nd_vpd_len > 0) {
	412	vpd.vpd_len = nd->nd_vpd_len;
	413	memcpy(&vpd.vpd_data, &nd->nd_vpd, nd->nd_vpd_len);
	414	} else {
	415	vpd.vpd_len = 0;
	416	}
	417
	418	if (copy_to_user(uarg, &vpd, sizeof(struct digi_vpd)))
	419	return -EFAULT;
	420	break;
	421	}
	422
	423	return 0;
	424	}
	425
	426	/**
	427	* dgrp_dpa() -- send data to the device monitor queue
	428	* @nd: pointer to a node structure
	429	* @buf: buffer of data to copy to the monitoring buffer
	430	* @len: number of bytes to transfer to the buffer
431	*
432	* Called by the net device routines to send data to the device
433	* monitor queue. If the device monitor buffer is too full to
434	* accept the data, it waits until the buffer is ready.
435	*/
436	static void dgrp_dpa(struct nd_struct nd, u8 buf, int nbuf)
437	{
438	int n;
439	int r;
440	unsigned long lock_flags;
441
442	/*
443	* Grab DPA lock.
444	*/
445	spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags);
446
447	/*
448	* Loop while data remains.
449	*/
450	while (nbuf > 0 && nd->nd_dpa_buf != NULL) {
451
452	n = (nd->nd_dpa_out - nd->nd_dpa_in - 1) & DPA_MASK;
453
454	/*
455	* Enforce flow control on the DPA device.
456	*/
457	if (n < (DPA_MAX - DPA_HIGH_WATER))
458	nd->nd_dpa_flag \|= DPA_WAIT_SPACE;
459
460	/*
461	* This should never happen, as the flow control above
462	* should have stopped things before they got to this point.
463	*/
464	if (n == 0) {
465	spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);
466	return;
467	}
468
469	/*
470	* Copy as much data as will fit.
471	*/
472
473	if (n > nbuf)
474	n = nbuf;
475
476	r = DPA_MAX - nd->nd_dpa_in;
477
478	if (r <= n) {
479	memcpy(nd->nd_dpa_buf + nd->nd_dpa_in, buf, r);
480
481	n -= r;
482
483	nd->nd_dpa_in = 0;
484
485	buf += r;
486	nbuf -= r;
487	}
488
489	memcpy(nd->nd_dpa_buf + nd->nd_dpa_in, buf, n);
490
491	nd->nd_dpa_in += n;
492
493	buf += n;
494	nbuf -= n;
495
496	if (nd->nd_dpa_in >= DPA_MAX)
497	pr_info_ratelimited("%s - nd->nd_dpa_in (%i) >= DPA_MAX\n",
498	__func__, nd->nd_dpa_in);
499
500	/*
501	* Wakeup any thread waiting for data
502	*/
503	if (nd->nd_dpa_flag & DPA_WAIT_DATA) {
504	nd->nd_dpa_flag &= ~DPA_WAIT_DATA;
505	wake_up_interruptible(&nd->nd_dpa_wqueue);
506	}
507	}
508
509	/*
510	* Release the DPA lock.
511	*/
512	spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags);
513	}
514
515	/**
516	* dgrp_monitor_data() -- builds a DPA data packet
517	* @nd: pointer to a node structure
518	* @type: type of message to be logged in the DPA buffer
519	* @buf: buffer of data to be logged in the DPA buffer
520	* @size -- number of bytes in the "buf" buffer
521	*/
522	void dgrp_dpa_data(struct nd_struct nd, int type, u8 buf, int size)
523	{
524	u8 header[5];
525
526	header[0] = type;
527
528	put_unaligned_be32(size, header + 1);
529
530	dgrp_dpa(nd, header, sizeof(header));
531	dgrp_dpa(nd, buf, size);
532	}