3 * $Id: unet.c,v 1.1 2001/01/25 22:03:39 mdw Exp $
5 * User-space network device support.
7 * (c) 1998 Mark Wooding
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of Usernet.
14 * Usernet is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * Usernet is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with Usernet; if not, write to the Free Software Foundation,
26 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
29 /*----- Revision history --------------------------------------------------*
32 * Revision 1.1 2001/01/25 22:03:39 mdw
33 * Initial check-in (somewhat belated).
37 /*----- Include files -----------------------------------------------------*/
39 #include <linux/module.h>
41 #include <asm/byteorder.h>
42 #include <asm/segment.h>
44 #include <linux/types.h>
45 #include <linux/kernel.h>
46 #include <linux/wait.h>
47 #include <linux/sched.h>
49 #include <linux/poll.h>
50 #include <linux/netdevice.h>
51 #include <linux/etherdevice.h>
52 #include <linux/if_arp.h>
53 #include <linux/malloc.h>
54 #include <linux/errno.h>
55 #include <linux/init.h>
60 MODULE_AUTHOR("Mark Wooding");
61 MODULE_DESCRIPTION("Allows userland handling of a network interface");
63 /*----- Debugging macros --------------------------------------------------*/
65 #define UNET_DEBUGALWAYS 1
66 #define UNET_DEBUGRUNTIME 0
67 #define UNET_DEBUGNEVER -1
69 /* --- If the macro isn't defined then be switchable at runtime --- */
72 # define UNET_DEBUG UNET_DEBUGRUNTIME
75 /* --- Define the base macro @D@ according to the debug setting --- */
77 #if UNET_DEBUG == UNET_DEBUGALWAYS
79 # define DIF(u, x) if ((u)->f & UNIF_DEBUG) { x }
80 #elif UNET_DEBUG == UNET_DEBUGRUNTIME
81 # define D(x) if (unet_debug) { x }
82 # define DIF(u, x) if ((u)->f & UNIF_DEBUG) { x }
83 #elif UNET_DEBUG == UNET_DEBUGNEVER
87 # error UNET_DEBUG set to invalid value (bug in configure script?)
90 /*----- Type definitions --------------------------------------------------*/
92 /* --- Unet connection status --- *
94 * Records are stored in a slightly strange doubly linked list. The list
95 * exists so that I can find the next unused sequence number when creating
96 * new connections. It's odd because of the type of the @prev@ node;
97 * rather than being the address of the previous item, it's the address of
98 * the previous item's pointer to me, which among other good things means
99 * that it works on the list head too.
103 struct unet
*next
, **prev
; /* List of unet blocks */
104 struct device nif
; /* Network interface block */
105 int seq
; /* Sequence number for connection */
106 char name
[UNET_NAMEMAX
]; /* Buffer for my interface name */
107 struct wait_queue
*q
; /* Wait list for device reads */
108 struct sk_buff_head skbq
; /* Queue of packets waiting */
109 struct enet_statistics e
; /* Pointer to statistics block */
110 unsigned short protocol
; /* Protocol for outgoing packets */
111 unsigned f
; /* Userful flags */
114 /*----- Static variables --------------------------------------------------*/
116 #if UNET_DEBUG == UNET_DEBUGRUNTIME
117 static int unet_debug
= 0;
118 MODULE_PARM(unet_debug
, "i");
121 static int unet_npersist
= UNET_NPERSIST
;
122 static int unet_maxif
= UNET_MAXIF
;
123 static struct unet
*unet_persistent
;
124 static struct unet
*unet_list
= 0;
126 MODULE_PARM(unet_npersist
, "i");
127 MODULE_PARM(unet_maxif
, "i");
129 /*----- Debugging code ----------------------------------------------------*/
131 #if UNET_DEBUG != UNET_DEBUGNEVER
133 /* --- @unet_dumpBlock@ --- *
135 * Arguments: @struct unet *u@ = pointer to block to dump
139 * Use: Dumps a unet object to syslogd.
142 static void unet_dumpBlock(struct unet
*u
)
144 printk(KERN_DEBUG
"unet: dumping unet block at %p\n", u
);
145 printk(KERN_DEBUG
" sequence number = %d\n", u
->seq
);
146 printk(KERN_DEBUG
" interface name = `%s'\n", u
->name
);
147 printk(KERN_DEBUG
" flags =%s%s%s\n",
148 u
->f
& UNIF_TRANS ?
" TRANS" : "",
149 u
->f
& UNIF_OPEN ?
" OPEN" : "",
150 u
->f
& UNIF_DEBUG ?
" DEBUG" : "");
151 printk(KERN_DEBUG
" interface type = %d\n", u
->nif
.type
);
152 printk(KERN_DEBUG
" header len = %d\n", u
->nif
.hard_header_len
);
153 printk(KERN_DEBUG
" mtu = %d\n", u
->nif
.mtu
);
154 printk(KERN_DEBUG
" protocol = %d\n", ntohs(u
->protocol
));
155 printk(KERN_DEBUG
" address len = %d\n", u
->nif
.addr_len
);
158 /* --- @unet_dump@ --- *
164 * Use: Dumps the entire unet state to syslogd.
167 static void unet_dump(void)
172 for (i
= 0; i
< unet_npersist
; i
++)
173 unet_dumpBlock(&unet_persistent
[i
]);
174 for (u
= unet_list
; u
; u
= u
->next
)
178 /* --- @unet_hexdump@ --- *
180 * Arguments: @const char *prefix@ = prefix to print on output lines
181 * @const void *b@ = pointer to block to dump
182 * @size_t sz@ = size of block to dump
186 * Use: Dumps a hex block to the kernel log.
189 #define UNET_HEXROWSZ 16
191 static void unet_hexdump(const char *prefix
, const char *b
, size_t sz
)
193 const unsigned char *p
= b
;
200 /* --- Now start work --- */
204 q
+= sprintf(q
, "%s%08lx : ", prefix
, o
);
205 for (i
= 0; i
< UNET_HEXROWSZ
; i
++) {
207 q
+= sprintf(q
, "%02x ", p
[i
]);
209 q
+= sprintf(q
, "** ");
211 *q
++ = ':'; *q
++ = ' ';
212 for (i
= 0; i
< UNET_HEXROWSZ
; i
++) {
214 *q
++ = (p
[i
] >= 32 && p
[i
] < 127) ? p
[i
] : '.';
221 c
= (sz
>= UNET_HEXROWSZ
) ? UNET_HEXROWSZ
: sz
;
222 sz
-= c
, p
+= c
, o
+= c
;
228 /*----- The unet network interfaces ---------------------------------------*/
230 /* --- @unet_ifopen@ --- *
232 * Arguments: @struct device *nif@ = pointer to network interface
234 * Returns: Zero or error condition.
236 * Use: Turns on the network interface ready for action. Oh, yes.
239 static int unet_ifopen(struct device
*nif
)
241 D( struct unet
*u
= nif
->priv
;
242 if (u
->f
& UNIF_DEBUG
)
243 printk(KERN_DEBUG
"unet: opening interface %s\n", u
->name
); )
248 /* --- @unet_ifclose@ --- *
250 * Arguments: @struct device *nif@ = pointer to network interface
252 * Returns: Zero or error condition.
254 * Use: Turns off the network interface.
257 static int unet_ifclose(struct device
*nif
)
259 D( struct unet
*u
= nif
->priv
;
260 if (u
->f
& UNIF_DEBUG
)
261 printk(KERN_DEBUG
"unet: closing interface %d\n", u
->seq
); )
266 /* --- @unet_iftx@ --- *
268 * Arguments: @struct sk_buff *skb@ = incoming network packet
269 * @struct device *nif@ = pointer to network interface
271 * Returns: Zero or error condition.
273 * Use: Queues a network packet ready for collection by the user
274 * end of the business.
277 static int unet_iftx(struct sk_buff
*skb
, struct device
*nif
)
279 struct unet
*u
= nif
->priv
;
283 printk(KERN_DEBUG
"unet: packet received on if %s\n", u
->name
);
284 unet_hexdump(KERN_DEBUG
" ", skb
->data
, skb
->len
); )
286 /* --- Discard packets when nobody's listening --- */
288 if ((u
->f
& UNIF_OPEN
) == 0) {
289 DIF(u
, printk(KERN_DEBUG
"unet: dropped packet: nobody's listening\n"); )
295 /* --- Discard packets when the queue's too long --- */
297 if (u
->skbq
.qlen
>= UNET_QMAXLEN
) {
298 DIF(u
, printk(KERN_DEBUG
"unet: refused packet: queue overflow\n"); )
302 /* --- Attach the buffer to the waiting list --- */
305 skb_queue_tail(&u
->skbq
, skb
);
307 DIF(u
, printk(KERN_DEBUG
"unet: queued packet OK\n"); )
309 /* --- If there are waiting processes, give 'em a kick --- */
312 DIF(u
, printk(KERN_DEBUG
"unet: waking up sleeping listeners\n"); )
313 wake_up_interruptible(&u
->q
);
318 /* --- @unet_ifgetstats@ --- *
320 * Arguments: @struct device *nif@ = pointer to network interface
322 * Returns: Pointer to a statistics buffer.
324 * Use: Returns a block of interface statistics.
327 static struct enet_statistics
*unet_ifgetstats(struct device
*nif
)
329 struct unet
*u
= nif
->priv
;
330 DIF(u
, printk(KERN_DEBUG
"unet: stats request for if %s\n", u
->name
); )
334 /* --- @unet_ifinit@ --- *
336 * Arguments: @struct device *nif@ = pointer to network interface
338 * Returns: Zero or error condition.
340 * Use: Initialises a unet network interface.
343 static int unet_ifinit(struct device
*nif
)
345 struct unet
*u
= nif
->priv
;
347 DIF(u
, printk(KERN_DEBUG
"unet: initialise interface %s\n", u
->name
); )
349 /* --- Initialise statistics gathering --- */
351 memset(&u
->e
, 0, sizeof(u
->e
));
352 u
->nif
.get_stats
= unet_ifgetstats
;
354 /* --- Opening and closing interfaces --- */
356 u
->nif
.open
= unet_ifopen
;
357 u
->nif
.stop
= unet_ifclose
;
359 /* --- Sending packets to the `outside world' --- */
361 u
->nif
.hard_start_xmit
= unet_iftx
;
363 /* --- Some initialisation magic --- */
366 for (i
= 0; i
< DEV_NUMBUFFS
; i
++)
367 skb_queue_head_init(&u
->nif
.buffs
[i
]);
370 /* --- Configure other grotty bits of the interface --- */
372 u
->nif
.hard_header
= 0;
373 u
->nif
.rebuild_header
= 0;
374 u
->nif
.set_mac_address
= 0;
376 u
->nif
.type
= ARPHRD_LOOPBACK
; /* Got a better idea? */
377 u
->nif
.hard_header_len
= 0;
378 u
->nif
.mtu
= 1500 - MAX_HEADER
;
380 u
->nif
.tx_queue_len
= 16; /* I keep my own queue */
382 memset(u
->nif
.broadcast
, 0xFFu
, MAX_ADDR_LEN
);
384 u
->nif
.flags
= IFF_NOARP
;
386 /* --- Finished! --- */
391 /*----- Attachment management ---------------------------------------------*/
393 /* --- @unet_setup@ --- *
395 * Arguments: @struct unet *u@ = pointer to a unet block
396 * @int seq@ = sequence number to allocate
398 * Returns: Zero or error condition.
400 * Use: Initialises a unet block ready for action.
403 static int unet_setup(struct unet
*u
, int seq
)
405 static struct device tpl
;
408 D( printk(KERN_DEBUG
"unet: setting up unet block %d\n", seq
); )
410 /* --- A little bit of initialisation --- */
416 /* --- Inherit device debug flag from global flag --- */
418 #if UNET_DEBUG == UNET_DEBUGRUNTIME
421 #elif UNET_DEBUG == UNET_DEBUGALWAYS
425 /* --- Set up the network device --- */
428 sprintf(u
->name
, "unet%d", seq
);
429 u
->nif
.name
= u
->name
;
431 u
->nif
.init
= unet_ifinit
;
432 u
->protocol
= htons(ETH_P_IP
);
434 if ((e
= register_netdev(&u
->nif
)) != 0) {
435 printk(KERN_ERR
"unet: couldn't register net interface\n");
439 /* --- Empty the skbuff list --- */
441 skb_queue_head_init(&u
->skbq
);
443 /* --- We're only finished, that's all --- */
448 /* --- @unet_flush@ --- *
450 * Arguments: @struct unet *u@ = pointer to a unet block
454 * Use: Releases all the packets waiting for transmission.
457 static void unet_flush(struct unet
*u
)
461 #if UNET_DEBUG != UNET_DEBUGNEVER
465 DIF(u
, printk(KERN_DEBUG
"unet: flushing packets on %s\n", u
->name
); )
467 while ((skb
= skb_dequeue(&u
->skbq
)) != 0) {
471 DIF(u
, printk(KERN_DEBUG
"unet: released %d waiting packets\n", i
); )
474 /* --- @unet_kill@ --- *
476 * Arguments: @struct unet *u@ = pointer to a unet block
480 * Use: Kills and decommissions a Usernet block.
483 static void unet_kill(struct unet
*u
)
486 unregister_netdev(&u
->nif
);
489 /*----- Handling the unet device ------------------------------------------*/
491 /* --- @unet_devopen@ --- *
493 * Arguments: @struct inode *ino@ = inode block to open
494 * @struct file *f@ = file block to play with
496 * Returns: Zero or error condition.
498 * Use: Handles the opening of a unet device.
501 static int unet_devopen(struct inode
*ino
, struct file
*f
)
503 struct unet
*u
, **up
;
507 D( printk(KERN_DEBUG
"unet: device open request\n"); )
509 /* --- Decide whether this is a persistent unet --- */
511 if ((seq
= MINOR(ino
->i_rdev
)) < unet_npersist
) {
512 u
= &unet_persistent
[seq
];
513 if (u
->f
& UNIF_OPEN
) {
517 D( printk(KERN_DEBUG
"unet: opened persistent %s\n", u
->name
); )
520 /* --- Otherwise we've got to create a new one --- */
524 /* --- Try to find a spare sequence number --- */
526 for (seq
= unet_npersist
, up
= &unet_list
; *up
!= 0;
527 seq
++, up
= &(*up
)->next
) {
528 if ((*up
)->seq
> seq
)
530 if (seq
>= unet_maxif
) {
531 printk("unet: all unets are occupied\n");
537 D( printk(KERN_DEBUG
"unet: allocated sequence number %d\n", seq
); )
539 /* --- Allocate a new block --- */
541 if ((u
= kmalloc(sizeof(*u
), GFP_KERNEL
)) == 0) {
542 printk(KERN_ERR
"unet: couldn't allocate a unet block\n");
547 /* --- Initialise the block --- */
549 if ((e
= unet_setup(u
, seq
)) != 0)
553 /* --- Link the block into the list --- */
558 (*up
)->prev
= &u
->next
;
561 D( printk(KERN_DEBUG
"unet: opened transient %d\n", seq
);
572 /* --- Tidy up after little disasters --- */
580 /* --- @unet_devclose@ --- *
582 * Arguments: @struct inode *ino@ = pointer to inode block
583 * @struct file *f@ = pointer to file block
587 * Use: Frees up a unet connection.
590 static int unet_devclose(struct inode
*ino
, struct file
*f
)
592 struct unet
*u
= f
->private_data
;
594 DIF(u
, printk(KERN_DEBUG
"unet: closing %s\n", u
->name
); )
596 /* --- A transient unet needs to be destroyed --- */
598 if (u
->f
& UNIF_TRANS
) {
601 u
->next
->prev
= u
->prev
;
604 D( printk(KERN_DEBUG
"unet: released transient unet\n"); )
607 /* --- A persistent unet needs to be shutdown --- */
612 DIF(u
, printk(KERN_DEBUG
"unet: unblocked persistent unet\n"); )
619 /* --- @unet_devpoll@ --- *
621 * Arguments: @struct file *f@ = pointer to my file block
622 * @struct poll_table_struct *p@ = poll table to wait on
624 * Returns: Nonzero if OK to continue, zero if waiting.
626 * Use: Plays a unet device's part in a @poll@(2) call.
629 static unsigned unet_devpoll(struct file
*f
, struct poll_table_struct
*p
)
631 struct unet
*u
= f
->private_data
;
634 DIF(u
, printk(KERN_DEBUG
"unet: poll request for %s\n", u
->name
); )
636 poll_wait(f
, &u
->q
, p
);
637 if (skb_peek(&u
->skbq
))
638 m
|= POLLIN
| POLLRDNORM
;
639 m
|= POLLOUT
| POLLWRNORM
;
643 /* --- @unet_devwrite@ --- *
645 * Arguments: @struct file *f@ = pointer to the file block
646 * @char *buf@ = pointer to caller's buffer
647 * @size_t sz@ = size of data to send
648 * @loff_t *off@ = offset to set (ignored)
650 * Returns: Number of bytes written, or error condition.
652 * Use: Sends a packet of data. No buffering is done.
655 static ssize_t
unet_devwrite(struct file
*f
, const char *buf
, size_t sz
,
658 struct unet
*u
= f
->private_data
;
661 DIF(u
, printk(KERN_DEBUG
"unet: write request for %s\n", u
->name
); )
663 /* --- Dump the packet we're meant to send --- */
666 if (u
->f
& UNIF_DEBUG
) {
667 void *b
= kmalloc(sz
, GFP_KERNEL
);
669 copy_from_user(b
, buf
, sz
);
670 unet_hexdump(KERN_DEBUG
" ", b
, sz
);
673 printk(KERN_NOTICE
"unet: not enough memory to dump block");
677 /* --- Allocate an skbuff for the block --- */
679 if ((skb
= dev_alloc_skb(sz
)) == 0) {
680 printk(KERN_ERR
"unet: failed to allocate skbuff\n");
685 /* --- Copy my data into the skbuff --- */
687 copy_from_user(skb_put(skb
, sz
), buf
, sz
);
689 skb
->mac
.raw
= skb
->data
;
690 skb
->protocol
= u
->protocol
;
696 /* --- @unet_devread@ --- *
698 * Arguments: @struct file *f@ = pointer to the file block
699 * @char *buf@ = pointer to caller's buffer
700 * @size_t sz@ = size of caller's buffer
701 * @loff_t *off@ = offset to set (ignored)
703 * Returns: Number of bytes read, or error condition.
705 * Use: Reads the next packet waiting for the device.
708 static ssize_t
unet_devread(struct file
*f
, char *buf
, size_t sz
,
711 struct unet
*u
= f
->private_data
;
714 DIF(u
, printk(KERN_DEBUG
"unet: read request for %s\n", u
->name
); )
716 /* --- Is the user sane? --- *
718 * The UDP protocol returns immediately in response to a zero-length read,
719 * and following this behaviour seems to cause `least surprise'.
725 /* --- Make sure there's a packet waiting for me --- */
727 if ((skb
= skb_dequeue(&u
->skbq
)) == 0) {
728 struct wait_queue wq
= { current
, 0 };
730 DIF(u
, printk(KERN_DEBUG
"unet: no packets waiting\n"); )
732 /* --- Check for nonblocking I/O --- */
734 if (f
->f_flags
& O_NONBLOCK
) {
735 DIF(u
, printk(KERN_DEBUG
"unet: nonblocking read: fail\n"); )
736 return (-EWOULDBLOCK
);
739 /* --- Otherwise block until there's a packet --- */
741 current
->state
= TASK_INTERRUPTIBLE
;
742 add_wait_queue(&u
->q
, &wq
);
746 if (signal_pending(current
)) {
748 DIF(u
, printk(KERN_DEBUG
"unet: interrupted by signal\n"); )
750 remove_wait_queue(&u
->q
, &wq
);
751 current
->state
= TASK_RUNNING
;
752 return (-ERESTARTSYS
);
755 DIF(u
, printk(KERN_DEBUG
"unet: blocking until packet arrives\n"); )
759 } while ((skb
= skb_dequeue(&u
->skbq
)) == 0);
761 remove_wait_queue(&u
->q
, &wq
);
762 current
->state
= TASK_RUNNING
;
765 DIF(u
, printk(KERN_DEBUG
"unet: found a packet\n"); )
767 /* --- There is now a packet waiting --- */
771 copy_to_user(buf
, skb
->data
, sz
);
774 DIF(u
, printk(KERN_DEBUG
"unet: passed packet on to user\n"); )
779 /* --- @unet_devioctl@ --- *
781 * Arguments: @struct inode *ino@ = pointer to inode block
782 * @struct file *f@ = pointer to file block
783 * @unsigned int c@ = command code to execute
784 * @unsigned long arg@ = argument passed to me
786 * Returns: Positive return value, or negative error condition.
788 * Use: Performs miscellaneous operations on a unet device.
791 static int unet_devioctl(struct inode
*ino
,
796 struct unet
*u
= f
->private_data
;
799 DIF(u
, printk(KERN_DEBUG
"unet: ioctl request for %s\n", u
->name
); )
803 /* --- @FIONREAD@ --- *
805 * Caller wants to know how big the next packet will be. Don't
810 struct sk_buff
*skb
= skb_peek(&u
->skbq
);
812 DIF(u
, printk(KERN_DEBUG
"unet: FIONREAD found %d bytes\n",
813 skb ? skb
->len
: 0); )
819 /* --- @UNIOCGINFO@ --- *
821 * Caller wants information about me.
825 struct unet_info uni
, *unip
;
827 DIF(u
, printk(KERN_DEBUG
"unet: UNIOCGINFO called\n"); )
829 unip
= (struct unet_info
*)arg
;
831 /* --- Special case --- *
833 * If the pointer is null, this call means `are you there?' and can
834 * be used to check for a Usernet attachment.
840 /* --- Ensure that the area can be written to --- */
842 if ((e
= verify_area(VERIFY_WRITE
, unip
, sizeof(*unip
))) != 0)
845 /* --- Build the information block in memory --- */
847 memset(&uni
, 0, sizeof(uni
)); /* Paranoia */
848 strncpy(uni
.uni_ifname
, u
->name
, UNET_NAMEMAX
);
849 uni
.uni_mtu
= u
->nif
.mtu
;
850 uni
.uni_family
= AF_INET
;
851 uni
.uni_proto
= ntohs(u
->protocol
);
852 uni
.uni_flags
= u
->f
;
854 /* --- Copy it to the user and return --- */
856 copy_to_user(unip
, &uni
, sizeof(uni
));
859 /* --- @UNIOCSDEBUG@ --- */
861 #if UNET_DEBUG != UNET_DEBUGNEVER
864 int o
= !!(u
->f
& UNIF_DEBUG
);
867 printk(KERN_DEBUG
"unet: UNIOCSDEBUG on %s: %s\n", u
->name
,
868 (o
&& n
) ?
"debugging still on" :
869 (!o
&& n
) ?
"debugging turned on" :
870 (o
&& !n
) ?
"debugging turned off" :
871 (!o
&& !n
) ?
"you can't see this message" :
872 "Logic failure: universe exploding");
881 /* --- @UNIOCGPROTO@ and @UNIOCSPROTO@ --- */
884 D( printk(KERN_DEBUG
"unet: UNIOCGPROTO on %s: read protocol: %d\n",
885 u
->name
, ntohs(u
->protocol
)); )
886 e
= ntohs(u
->protocol
);
889 D( printk(KERN_DEBUG
"unet: UNIOCSPROTO on %s: set protocol: %d\n",
890 u
->name
, (int)arg
); )
891 u
->protocol
= htons(arg
);
894 /* --- @UNIOCGGDEBUG@ and @UNIOCSGDEBUG@ --- */
897 D( printk(KERN_DEBUG
"unet: UNIOCGGDEBUG: get global debug: on\n"); )
898 #if UNET_DEBUG == UNET_DEBUGRUNTIME
900 #elif UNET_DEBUG == UNET_DEBUGALWAYS
902 #elif UNET_DEBUG == UNET_DEBUGNEVER
907 #if UNET_DEBUG == UNET_DEBUGRUNTIME
909 printk(KERN_DEBUG
"unet: UNIOCSGDEBUG: set global debug: %s\n",
910 (arg
&& unet_debug
) ?
"debugging still on" :
911 (!arg
&& unet_debug
) ?
"debugging turned off" :
912 (arg
&& !unet_debug
) ?
"debugging turned on" :
913 (!arg
&& !unet_debug
) ?
"you can't see this message" :
914 "Logic failure: universe exploding");
919 /* --- @UNIOCDUMP@ --- */
921 #if UNET_DEBUG != UNET_DEBUGNEVER
923 D( unet_dumpBlock(u
); )
927 /* --- @UNIOCGMAXIF@ --- */
930 D( printk(KERN_DEBUG
"unet: UNIOCGMAXIF: unet_maxif = %d\n",
935 /* --- @UNIOCSMAXIF@ --- */
939 if (arg
< unet_npersist
|| arg
> INT_MAX
)
941 for (u
= unet_list
; u
; u
= u
->next
) {
942 if (u
->seq
>= unet_npersist
)
946 D( printk(KERN_DEBUG
"unet: UNIOCSMAXIF: unet_maxif = %d\n",
950 /* --- Everything else --- *
956 D( printk(KERN_DEBUG
"unet: unknown ioctl %08x\n", c
); )
963 /*----- The unet device ---------------------------------------------------*/
965 /* --- Device operations --- */
967 struct file_operations unet_fops
= {
968 0, /* unet_devlseek */
971 0, /* unet_devreaddir */
974 0, /* unet_devmmap */
980 /*----- Initaliseation and shutdown ---------------------------------------*/
982 /* --- @unet_init@ --- *
986 * Returns: Zero or error condition.
988 * Use: Registers the unet device.
991 __initfunc(int unet_init(void))
996 /* --- Register my character device --- */
998 if ((e
= register_chrdev(UNET_MAJOR
, "unet", &unet_fops
)) != 0) {
999 printk(KERN_ERR
"unet: can't claim major device %d\n", UNET_MAJOR
);
1003 /* --- Make the persistent unet devices --- */
1005 if ((unet_persistent
= kmalloc(unet_npersist
* sizeof(struct unet
),
1006 GFP_KERNEL
)) == 0) {
1007 printk(KERN_ERR
"unet: can't allocate %i persistent unet blocks",
1013 for (i
= 0; i
< unet_npersist
; i
++) {
1014 if ((e
= unet_setup(&unet_persistent
[i
], i
)) != 0) {
1015 printk(KERN_ERR
"unet: can't create persistent unet %d\n", i
);
1025 /* --- Some bad stuff happened --- */
1030 unregister_netdev(&unet_persistent
[i
].nif
);
1032 kfree(unet_persistent
);
1035 unregister_chrdev(UNET_MAJOR
, "unet");
1043 /* --- @init_module@ --- *
1047 * Returns: Zero or error condition.
1049 * Use: Initialises the unet kernel module.
1052 int init_module(void)
1054 if (unet_npersist
< 0 || unet_maxif
< unet_npersist
1055 #if UNET_DEBUG == UNET_DEBUGRUNTIME
1056 || (unet_debug
!= 0 && unet_debug
!= 1)
1060 return (unet_init());
1063 /* --- @cleanup_module@ --- *
1069 * Use: Tidies up the unet module ready for it to be killed.
1072 void cleanup_module(void)
1076 for (i
= 0; i
< unet_npersist
; i
++) {
1077 D( printk(KERN_DEBUG
"unet: releasing persistent unet %d\n", i
); )
1078 unet_kill(&unet_persistent
[i
]);
1080 kfree(unet_persistent
);
1082 unregister_chrdev(UNET_MAJOR
, "unet");
1087 /*----- That's all, folks -------------------------------------------------*/