1 /*****************************************************************************
3 * Copyright 1999 Digi International (www.digi.com)
4 * James Puzzo <jamesp at digi dot com>
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)
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.
26 * Handle the file operations required for the "monitor" devices.
27 * Includes those functions required to register the "mon" devices
36 #include <linux/module.h>
37 #include <linux/tty.h>
38 #include <linux/sched.h>
39 #include <asm/unaligned.h>
40 #include <linux/slab.h>
41 #include <linux/proc_fs.h>
42 #include <linux/uaccess.h>
44 #include "dgrp_common.h"
46 /* File operation declarations */
47 static int dgrp_mon_open(struct inode *, struct file *);
48 static int dgrp_mon_release(struct inode *, struct file *);
49 static ssize_t dgrp_mon_read(struct file *, char __user *, size_t, loff_t *);
50 static long dgrp_mon_ioctl(struct file *file, unsigned int cmd,
53 const struct file_operations dgrp_mon_ops = {
55 .read = dgrp_mon_read,
56 .unlocked_ioctl = dgrp_mon_ioctl,
57 .open = dgrp_mon_open,
58 .release = dgrp_mon_release,
62 * dgrp_mon_open() -- open /proc/dgrp/ports device for a PortServer
63 * @inode: struct inode *
64 * @file: struct file *
66 * Open function to open the /proc/dgrp/ports device for a PortServer.
68 static int dgrp_mon_open(struct inode *inode, struct file *file)
76 rtn = try_module_get(THIS_MODULE);
82 if (!capable(CAP_SYS_ADMIN)) {
88 * Make sure that the "private_data" field hasn't already been used.
90 if (file->private_data) {
96 * Get the node pointer, and fail if it doesn't exist.
104 file->private_data = (void *) nd;
107 * Allocate the monitor buffer.
113 down(&nd->nd_mon_semaphore);
115 if (nd->nd_mon_buf) {
120 nd->nd_mon_buf = kmalloc(MON_MAX, GFP_KERNEL);
122 if (!nd->nd_mon_buf) {
128 * Enter an RPDUMP file header into the buffer.
131 buf = nd->nd_mon_buf;
133 strcpy(buf, RPDUMP_MAGIC);
134 buf += strlen(buf) + 1;
136 do_gettimeofday(&tv);
139 * tv.tv_sec might be a 64 bit quantity. Pare
140 * it down to 32 bits before attempting to encode
143 time = (uint32_t) (tv.tv_sec & 0xffffffff);
145 put_unaligned_be32(time, buf);
146 put_unaligned_be16(0, buf + 4);
149 if (nd->nd_tx_module) {
150 buf[0] = RPDUMP_CLIENT;
151 put_unaligned_be32(0, buf + 1);
152 put_unaligned_be16(1, buf + 5);
153 buf[7] = 0xf0 + nd->nd_tx_module;
157 if (nd->nd_rx_module) {
158 buf[0] = RPDUMP_SERVER;
159 put_unaligned_be32(0, buf + 1);
160 put_unaligned_be16(1, buf + 5);
161 buf[7] = 0xf0 + nd->nd_rx_module;
166 nd->nd_mon_in = buf - nd->nd_mon_buf;
167 nd->nd_mon_lbolt = jiffies;
170 up(&nd->nd_mon_semaphore);
174 module_put(THIS_MODULE);
180 * dgrp_mon_release() - Close the MON device for a particular PortServer
181 * @inode: struct inode *
182 * @file: struct file *
184 static int dgrp_mon_release(struct inode *inode, struct file *file)
186 struct nd_struct *nd;
189 * Get the node pointer, and quit if it doesn't exist.
191 nd = (struct nd_struct *)(file->private_data);
196 * Free the monitor buffer.
199 down(&nd->nd_mon_semaphore);
201 kfree(nd->nd_mon_buf);
202 nd->nd_mon_buf = NULL;
203 nd->nd_mon_out = nd->nd_mon_in;
206 * Wakeup any thread waiting for buffer space.
209 if (nd->nd_mon_flag & MON_WAIT_SPACE) {
210 nd->nd_mon_flag &= ~MON_WAIT_SPACE;
211 wake_up_interruptible(&nd->nd_mon_wqueue);
214 up(&nd->nd_mon_semaphore);
217 * Make sure there is no thread in the middle of writing a packet.
219 down(&nd->nd_net_semaphore);
220 up(&nd->nd_net_semaphore);
223 module_put(THIS_MODULE);
224 file->private_data = NULL;
229 * dgrp_mon_read() -- Copy data from the monitoring buffer to the user
231 static ssize_t dgrp_mon_read(struct file *file, char __user *buf, size_t count,
234 struct nd_struct *nd;
241 * Get the node pointer, and quit if it doesn't exist.
243 nd = (struct nd_struct *)(file->private_data);
248 * Wait for some data to appear in the buffer.
251 down(&nd->nd_mon_semaphore);
254 res = (nd->nd_mon_in - nd->nd_mon_out) & MON_MASK;
259 nd->nd_mon_flag |= MON_WAIT_DATA;
261 up(&nd->nd_mon_semaphore);
264 * Go to sleep waiting until the condition becomes true.
266 rtn = wait_event_interruptible(nd->nd_mon_wqueue,
267 ((nd->nd_mon_flag & MON_WAIT_DATA) == 0));
272 down(&nd->nd_mon_semaphore);
276 * Read whatever is there.
282 r = MON_MAX - nd->nd_mon_out;
285 rtn = copy_to_user((void __user *)buf,
286 nd->nd_mon_buf + nd->nd_mon_out, r);
288 up(&nd->nd_mon_semaphore);
297 rtn = copy_to_user((void __user *) buf + offset,
298 nd->nd_mon_buf + nd->nd_mon_out, res);
300 up(&nd->nd_mon_semaphore);
304 nd->nd_mon_out += res;
308 up(&nd->nd_mon_semaphore);
311 * Wakeup any thread waiting for buffer space.
314 if (nd->nd_mon_flag & MON_WAIT_SPACE) {
315 nd->nd_mon_flag &= ~MON_WAIT_SPACE;
316 wake_up_interruptible(&nd->nd_mon_wqueue);
322 /* ioctl is not valid on monitor device */
323 static long dgrp_mon_ioctl(struct file *file, unsigned int cmd,