- 根目录:
- 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 <linux/slab.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);
strlcpy(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:
memset(&vpd, 0, sizeof(vpd));
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);
}