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/proc_fs.h>
41 #include <linux/uaccess.h>
43 #include "dgrp_common.h"
45 /* File operation declarations */
46 static int dgrp_mon_open(struct inode
*, struct file
*);
47 static int dgrp_mon_release(struct inode
*, struct file
*);
48 static ssize_t
dgrp_mon_read(struct file
*, char __user
*, size_t, loff_t
*);
49 static long dgrp_mon_ioctl(struct file
*file
, unsigned int cmd
,
52 static const struct file_operations mon_ops
= {
54 .read
= dgrp_mon_read
,
55 .unlocked_ioctl
= dgrp_mon_ioctl
,
56 .open
= dgrp_mon_open
,
57 .release
= dgrp_mon_release
,
60 static struct inode_operations mon_inode_ops
= {
61 .permission
= dgrp_inode_permission
64 void dgrp_register_mon_hook(struct proc_dir_entry
*de
)
66 struct nd_struct
*node
= de
->data
;
68 de
->proc_iops
= &mon_inode_ops
;
69 de
->proc_fops
= &mon_ops
;
71 sema_init(&node
->nd_mon_semaphore
, 1);
75 * dgrp_mon_open() -- open /proc/dgrp/ports device for a PortServer
76 * @inode: struct inode *
77 * @file: struct file *
79 * Open function to open the /proc/dgrp/ports device for a PortServer.
81 static int dgrp_mon_open(struct inode
*inode
, struct file
*file
)
84 struct proc_dir_entry
*de
;
90 rtn
= try_module_get(THIS_MODULE
);
96 if (!capable(CAP_SYS_ADMIN
)) {
102 * Make sure that the "private_data" field hasn't already been used.
104 if (file
->private_data
) {
110 * Get the node pointer, and fail if it doesn't exist.
118 nd
= (struct nd_struct
*)de
->data
;
124 file
->private_data
= (void *) nd
;
127 * Allocate the monitor buffer.
133 down(&nd
->nd_mon_semaphore
);
135 if (nd
->nd_mon_buf
) {
140 nd
->nd_mon_buf
= kmalloc(MON_MAX
, GFP_KERNEL
);
142 if (!nd
->nd_mon_buf
) {
148 * Enter an RPDUMP file header into the buffer.
151 buf
= nd
->nd_mon_buf
;
153 strcpy(buf
, RPDUMP_MAGIC
);
154 buf
+= strlen(buf
) + 1;
156 do_gettimeofday(&tv
);
159 * tv.tv_sec might be a 64 bit quantity. Pare
160 * it down to 32 bits before attempting to encode
163 time
= (uint32_t) (tv
.tv_sec
& 0xffffffff);
165 put_unaligned_be32(time
, buf
);
166 put_unaligned_be16(0, buf
+ 4);
169 if (nd
->nd_tx_module
) {
170 buf
[0] = RPDUMP_CLIENT
;
171 put_unaligned_be32(0, buf
+ 1);
172 put_unaligned_be16(1, buf
+ 5);
173 buf
[7] = 0xf0 + nd
->nd_tx_module
;
177 if (nd
->nd_rx_module
) {
178 buf
[0] = RPDUMP_SERVER
;
179 put_unaligned_be32(0, buf
+ 1);
180 put_unaligned_be16(1, buf
+ 5);
181 buf
[7] = 0xf0 + nd
->nd_rx_module
;
186 nd
->nd_mon_in
= buf
- nd
->nd_mon_buf
;
187 nd
->nd_mon_lbolt
= jiffies
;
190 up(&nd
->nd_mon_semaphore
);
194 module_put(THIS_MODULE
);
200 * dgrp_mon_release() - Close the MON device for a particular PortServer
201 * @inode: struct inode *
202 * @file: struct file *
204 static int dgrp_mon_release(struct inode
*inode
, struct file
*file
)
206 struct nd_struct
*nd
;
209 * Get the node pointer, and quit if it doesn't exist.
211 nd
= (struct nd_struct
*)(file
->private_data
);
216 * Free the monitor buffer.
219 down(&nd
->nd_mon_semaphore
);
221 kfree(nd
->nd_mon_buf
);
222 nd
->nd_mon_buf
= NULL
;
223 nd
->nd_mon_out
= nd
->nd_mon_in
;
226 * Wakeup any thread waiting for buffer space.
229 if (nd
->nd_mon_flag
& MON_WAIT_SPACE
) {
230 nd
->nd_mon_flag
&= ~MON_WAIT_SPACE
;
231 wake_up_interruptible(&nd
->nd_mon_wqueue
);
234 up(&nd
->nd_mon_semaphore
);
237 * Make sure there is no thread in the middle of writing a packet.
239 down(&nd
->nd_net_semaphore
);
240 up(&nd
->nd_net_semaphore
);
243 module_put(THIS_MODULE
);
244 file
->private_data
= NULL
;
249 * dgrp_mon_read() -- Copy data from the monitoring buffer to the user
251 static ssize_t
dgrp_mon_read(struct file
*file
, char __user
*buf
, size_t count
,
254 struct nd_struct
*nd
;
261 * Get the node pointer, and quit if it doesn't exist.
263 nd
= (struct nd_struct
*)(file
->private_data
);
268 * Wait for some data to appear in the buffer.
271 down(&nd
->nd_mon_semaphore
);
274 res
= (nd
->nd_mon_in
- nd
->nd_mon_out
) & MON_MASK
;
279 nd
->nd_mon_flag
|= MON_WAIT_DATA
;
281 up(&nd
->nd_mon_semaphore
);
284 * Go to sleep waiting until the condition becomes true.
286 rtn
= wait_event_interruptible(nd
->nd_mon_wqueue
,
287 ((nd
->nd_mon_flag
& MON_WAIT_DATA
) == 0));
292 down(&nd
->nd_mon_semaphore
);
296 * Read whatever is there.
302 r
= MON_MAX
- nd
->nd_mon_out
;
305 rtn
= copy_to_user((void __user
*)buf
,
306 nd
->nd_mon_buf
+ nd
->nd_mon_out
, r
);
308 up(&nd
->nd_mon_semaphore
);
317 rtn
= copy_to_user((void __user
*) buf
+ offset
,
318 nd
->nd_mon_buf
+ nd
->nd_mon_out
, res
);
320 up(&nd
->nd_mon_semaphore
);
324 nd
->nd_mon_out
+= res
;
328 up(&nd
->nd_mon_semaphore
);
331 * Wakeup any thread waiting for buffer space.
334 if (nd
->nd_mon_flag
& MON_WAIT_SPACE
) {
335 nd
->nd_mon_flag
&= ~MON_WAIT_SPACE
;
336 wake_up_interruptible(&nd
->nd_mon_wqueue
);
342 /* ioctl is not valid on monitor device */
343 static long dgrp_mon_ioctl(struct file
*file
, unsigned int cmd
,