Remove ancient example code from the architecture handbook.
Approved by: bcr (mentor)
This commit is contained in:
Eitan Adler
parent
1af7bc46fb
commit
ee9afa89e4
Notes:
svn2git
2020-12-08 03:00:23 +00:00
svn path=/head/; revision=40051
1 changed files with 1 additions and 165 deletions
|
|
@ -208,171 +208,7 @@ KMOD=skeleton
|
||||||
|
|
||||||
<para>This simple example pseudo-device remembers whatever values
|
<para>This simple example pseudo-device remembers whatever values
|
||||||
you write to it and can then supply them back to you when you
|
you write to it and can then supply them back to you when you
|
||||||
read from it. Two versions are shown, one for &os; 4.X and
|
read from it.</para>
|
||||||
one for &os; 5.X.</para>
|
|
||||||
|
|
||||||
<example>
|
|
||||||
<title>Example of a Sample Echo Pseudo-Device Driver for
|
|
||||||
&os; 4.X</title>
|
|
||||||
|
|
||||||
<programlisting>/*
|
|
||||||
* Simple `echo' pseudo-device KLD
|
|
||||||
*
|
|
||||||
* Murray Stokely
|
|
||||||
*/
|
|
||||||
|
|
||||||
#define MIN(a,b) (((a) < (b)) ? (a) : (b))
|
|
||||||
|
|
||||||
#include <sys/types.h>
|
|
||||||
#include <sys/module.h>
|
|
||||||
#include <sys/systm.h> /* uprintf */
|
|
||||||
#include <sys/errno.h>
|
|
||||||
#include <sys/param.h> /* defines used in kernel.h */
|
|
||||||
#include <sys/kernel.h> /* types used in module initialization */
|
|
||||||
#include <sys/conf.h> /* cdevsw struct */
|
|
||||||
#include <sys/uio.h> /* uio struct */
|
|
||||||
#include <sys/malloc.h>
|
|
||||||
|
|
||||||
#define BUFFERSIZE 256
|
|
||||||
|
|
||||||
/* Function prototypes */
|
|
||||||
d_open_t echo_open;
|
|
||||||
d_close_t echo_close;
|
|
||||||
d_read_t echo_read;
|
|
||||||
d_write_t echo_write;
|
|
||||||
|
|
||||||
/* Character device entry points */
|
|
||||||
static struct cdevsw echo_cdevsw = {
|
|
||||||
echo_open,
|
|
||||||
echo_close,
|
|
||||||
echo_read,
|
|
||||||
echo_write,
|
|
||||||
noioctl,
|
|
||||||
nopoll,
|
|
||||||
nommap,
|
|
||||||
nostrategy,
|
|
||||||
"echo",
|
|
||||||
33, /* reserved for lkms - /usr/src/sys/conf/majors */
|
|
||||||
nodump,
|
|
||||||
nopsize,
|
|
||||||
D_TTY,
|
|
||||||
-1
|
|
||||||
};
|
|
||||||
|
|
||||||
typedef struct s_echo {
|
|
||||||
char msg[BUFFERSIZE];
|
|
||||||
int len;
|
|
||||||
} t_echo;
|
|
||||||
|
|
||||||
/* vars */
|
|
||||||
static dev_t sdev;
|
|
||||||
static int count;
|
|
||||||
static t_echo *echomsg;
|
|
||||||
|
|
||||||
MALLOC_DECLARE(M_ECHOBUF);
|
|
||||||
MALLOC_DEFINE(M_ECHOBUF, "echobuffer", "buffer for echo module");
|
|
||||||
|
|
||||||
/*
|
|
||||||
* This function is called by the kld[un]load(2) system calls to
|
|
||||||
* determine what actions to take when a module is loaded or unloaded.
|
|
||||||
*/
|
|
||||||
|
|
||||||
static int
|
|
||||||
echo_loader(struct module *m, int what, void *arg)
|
|
||||||
{
|
|
||||||
int err = 0;
|
|
||||||
|
|
||||||
switch (what) {
|
|
||||||
case MOD_LOAD: /* kldload */
|
|
||||||
sdev = make_dev(<literal>&</literal>echo_cdevsw,
|
|
||||||
0,
|
|
||||||
UID_ROOT,
|
|
||||||
GID_WHEEL,
|
|
||||||
0600,
|
|
||||||
"echo");
|
|
||||||
/* kmalloc memory for use by this driver */
|
|
||||||
MALLOC(echomsg, t_echo *, sizeof(t_echo), M_ECHOBUF, M_WAITOK);
|
|
||||||
printf("Echo device loaded.\n");
|
|
||||||
break;
|
|
||||||
case MOD_UNLOAD:
|
|
||||||
destroy_dev(sdev);
|
|
||||||
FREE(echomsg,M_ECHOBUF);
|
|
||||||
printf("Echo device unloaded.\n");
|
|
||||||
break;
|
|
||||||
default:
|
|
||||||
err = EOPNOTSUPP;
|
|
||||||
break;
|
|
||||||
}
|
|
||||||
return(err);
|
|
||||||
}
|
|
||||||
|
|
||||||
int
|
|
||||||
echo_open(dev_t dev, int oflags, int devtype, struct proc *p)
|
|
||||||
{
|
|
||||||
int err = 0;
|
|
||||||
|
|
||||||
uprintf("Opened device \"echo\" successfully.\n");
|
|
||||||
return(err);
|
|
||||||
}
|
|
||||||
|
|
||||||
int
|
|
||||||
echo_close(dev_t dev, int fflag, int devtype, struct proc *p)
|
|
||||||
{
|
|
||||||
uprintf("Closing device \"echo.\"\n");
|
|
||||||
return(0);
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* The read function just takes the buf that was saved via
|
|
||||||
* echo_write() and returns it to userland for accessing.
|
|
||||||
* uio(9)
|
|
||||||
*/
|
|
||||||
|
|
||||||
int
|
|
||||||
echo_read(dev_t dev, struct uio *uio, int ioflag)
|
|
||||||
{
|
|
||||||
int err = 0;
|
|
||||||
int amt;
|
|
||||||
|
|
||||||
/*
|
|
||||||
* How big is this read operation? Either as big as the user wants,
|
|
||||||
* or as big as the remaining data
|
|
||||||
*/
|
|
||||||
amt = MIN(uio->uio_resid, (echomsg->len - uio->uio_offset > 0) ?
|
|
||||||
echomsg->len - uio->uio_offset : 0);
|
|
||||||
if ((err = uiomove(echomsg->msg + uio->uio_offset,amt,uio)) != 0) {
|
|
||||||
uprintf("uiomove failed!\n");
|
|
||||||
}
|
|
||||||
return(err);
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* echo_write takes in a character string and saves it
|
|
||||||
* to buf for later accessing.
|
|
||||||
*/
|
|
||||||
|
|
||||||
int
|
|
||||||
echo_write(dev_t dev, struct uio *uio, int ioflag)
|
|
||||||
{
|
|
||||||
int err = 0;
|
|
||||||
|
|
||||||
/* Copy the string in from user memory to kernel memory */
|
|
||||||
err = copyin(uio->uio_iov->iov_base, echomsg->msg,
|
|
||||||
MIN(uio->uio_iov->iov_len, BUFFERSIZE - 1));
|
|
||||||
|
|
||||||
/* Now we need to null terminate, then record the length */
|
|
||||||
*(echomsg->msg + MIN(uio->uio_iov->iov_len, BUFFERSIZE - 1)) = 0;
|
|
||||||
echomsg->len = MIN(uio->uio_iov->iov_len, BUFFERSIZE);
|
|
||||||
|
|
||||||
if (err != 0) {
|
|
||||||
uprintf("Write failed: bad address!\n");
|
|
||||||
}
|
|
||||||
count++;
|
|
||||||
return(err);
|
|
||||||
}
|
|
||||||
|
|
||||||
DEV_MODULE(echo,echo_loader,NULL);</programlisting>
|
|
||||||
</example>
|
|
||||||
|
|
||||||
<example>
|
<example>
|
||||||
<title>Example of a Sample Echo Pseudo-Device Driver for
|
<title>Example of a Sample Echo Pseudo-Device Driver for
|
||||||
|
|
|
||||||
Loading…
Reference in a new issue