Date: Mon, 27 Mar 2000 18:17:19 -0800 (PST) From: brooks@one-eyed-alien.net To: FreeBSD-gnats-submit@freebsd.org Subject: kern/17629: "almost clone" patch for device snp Message-ID: <200003280217.SAA00582@minya.sea.one-eyed-alien.net>
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>Number: 17629
>Category: kern
>Synopsis: "almost clone" patch for device snp
>Confidential: no
>Severity: non-critical
>Priority: low
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: change-request
>Submitter-Id: current-users
>Arrival-Date: Mon Mar 27 18:20:01 PST 2000
>Closed-Date:
>Last-Modified:
>Originator: Brooks Davis
>Release: FreeBSD 5.0-CURRENT i386
>Organization:
The Aerospace Corporation
>Environment:
FreeBSD minya 5.0-CURRENT FreeBSD 5.0-CURRENT #15: Mon Mar 27 17:45:47 PST 2000 root@minya:/usr/src/sys/compile/MINYA i386
>Description:
The following patch modifies the snp device to grow automagicaly like
bpf, tun, and pty do. I had some time on my hands so I looked up phk's
message, "Kernel hacker tasks seek intrested hackers", and this one
looked easy, useful, and somewhat informative so I did it. The patch
is mostly based on rev 1.53 of bpf.c which did the same thing to bpf.
>How-To-Repeat:
>Fix:
The patch is below. LINT should also be modified changing:
pseudo-device snp 3 #Snoop device - to look at pty/vty/etc..
to:
pseudo-device snp #Snoop device - to look at pty/vty/etc..
Index: tty_snoop.c
===================================================================
RCS file: /home/ncvs/src/sys/kern/tty_snoop.c,v
retrieving revision 1.45
diff -u -r1.45 tty_snoop.c
--- tty_snoop.c 1999/11/18 06:39:47 1.45
+++ tty_snoop.c 2000/03/28 01:30:32
@@ -32,6 +32,8 @@
#include <sys/snoop.h>
#include <sys/vnode.h>
+MALLOC_DEFINE(M_SNP, "snp", "Snoop Interface");
+
static d_open_t snpopen;
static d_close_t snpclose;
static d_read_t snpread;
@@ -62,8 +64,6 @@
#define MIN(a,b) (((a)<(b))?(a):(b))
#endif
-static struct snoop snoopsw[NSNP];
-
static struct tty *snpdevtotty __P((dev_t dev));
static int snp_detach __P((struct snoop *snp));
@@ -90,8 +90,8 @@
struct uio *uio;
int flag;
{
- int unit = minor(dev), len, i, error;
- struct snoop *snp = &snoopsw[unit];
+ int len, i, error;
+ struct snoop *snp = dev->si_drv1;
struct tty *tp;
char c[SNP_INPUT_BUF];
@@ -131,8 +131,8 @@
struct uio *uio;
int flag;
{
- int unit = minor(dev), s;
- struct snoop *snp = &snoopsw[unit];
+ int s;
+ struct snoop *snp = dev->si_drv1;
int len, n, nblen, error = 0;
caddr_t from;
char *nbuf;
@@ -174,9 +174,9 @@
if (((nblen / 2) >= SNOOP_MINLEN) && (nblen / 2) >= snp->snp_len) {
while (((nblen / 2) >= snp->snp_len) && ((nblen / 2) >= SNOOP_MINLEN))
nblen = nblen / 2;
- if ((nbuf = malloc(nblen, M_TTYS, M_NOWAIT)) != NULL) {
+ if ((nbuf = malloc(nblen, M_SNP, M_NOWAIT)) != NULL) {
bcopy(snp->snp_buf + snp->snp_base, nbuf, snp->snp_len);
- free(snp->snp_buf, M_TTYS);
+ free(snp->snp_buf, M_SNP);
snp->snp_buf = nbuf;
snp->snp_blen = nblen;
snp->snp_base = 0;
@@ -213,12 +213,6 @@
if (n == 0)
return 0;
-#ifdef DIAGNOSTIC
- if (!(snp->snp_flags & SNOOP_OPEN)) {
- printf("Snoop: data coming to closed device.\n");
- return 0;
- }
-#endif
if (snp->snp_flags & SNOOP_DOWN) {
printf("Snoop: more data to down interface.\n");
return 0;
@@ -246,9 +240,9 @@
nblen = snp->snp_blen * 2;
s_free = nblen - (snp->snp_len + snp->snp_base);
}
- if ((n <= s_free) && (nbuf = malloc(nblen, M_TTYS, M_NOWAIT))) {
+ if ((n <= s_free) && (nbuf = malloc(nblen, M_SNP, M_NOWAIT))) {
bcopy(snp->snp_buf + snp->snp_base, nbuf, snp->snp_len);
- free(snp->snp_buf, M_TTYS);
+ free(snp->snp_buf, M_SNP);
snp->snp_buf = nbuf;
snp->snp_blen = nblen;
snp->snp_base = 0;
@@ -291,26 +285,22 @@
struct proc *p;
{
struct snoop *snp;
- register int unit, error;
+ register int error;
if ((error = suser(p)) != 0)
return (error);
- if ((unit = minor(dev)) >= NSNP)
- return (ENXIO);
+ snp = dev->si_drv1;
- snp = &snoopsw[unit];
+ if (snp)
+ return (EBUSY);
- if (snp->snp_flags & SNOOP_OPEN)
- return (ENXIO);
+ make_dev(&snp_cdevsw, minor(dev), 0, 0, 0600, "bpf%d", lminor(dev));
+ MALLOC(snp, struct snoop *, sizeof(*snp), M_SNP, M_WAITOK);
+ bzero(snp, sizeof(*snp));
+ dev->si_drv1 = snp;
- /*
- * We intentionally do not OR flags with SNOOP_OPEN,but set them so
- * all previous settings (especially SNOOP_OFLOW) will be cleared.
- */
- snp->snp_flags = SNOOP_OPEN;
-
- snp->snp_buf = malloc(SNOOP_MINLEN, M_TTYS, M_WAITOK);
+ snp->snp_buf = malloc(SNOOP_MINLEN, M_SNP, M_WAITOK);
snp->snp_blen = SNOOP_MINLEN;
snp->snp_base = 0;
snp->snp_len = 0;
@@ -367,14 +357,15 @@
int fmt;
struct proc *p;
{
- register int unit = minor(dev);
- struct snoop *snp = &snoopsw[unit];
+ int error;
+ struct snoop *snp = dev->si_drv1;
- snp->snp_blen = 0;
- free(snp->snp_buf, M_TTYS);
- snp->snp_flags &= ~SNOOP_OPEN;
+ free(snp->snp_buf, M_SNP);
+ error = snp_detach(snp);
+ FREE(snp, M_SNP);
+ dev->si_drv1 = 0;
- return (snp_detach(snp));
+ return (error);
}
int
@@ -382,8 +373,8 @@
struct snoop *snp;
{
snp->snp_blen = SNOOP_MINLEN;
- free(snp->snp_buf, M_TTYS);
- snp->snp_buf = malloc(SNOOP_MINLEN, M_TTYS, M_WAITOK);
+ free(snp->snp_buf, M_SNP);
+ snp->snp_buf = malloc(SNOOP_MINLEN, M_SNP, M_WAITOK);
snp->snp_flags |= SNOOP_DOWN;
return (snp_detach(snp));
@@ -398,9 +389,9 @@
int flags;
struct proc *p;
{
- int unit = minor(dev), s;
+ int s;
dev_t tdev;
- struct snoop *snp = &snoopsw[unit];
+ struct snoop *snp = dev->si_drv1;
struct tty *tp, *tpo;
switch (cmd) {
@@ -489,8 +480,7 @@
int events;
struct proc *p;
{
- int unit = minor(dev);
- struct snoop *snp = &snoopsw[unit];
+ struct snoop *snp = dev->si_drv1;
int revents = 0;
@@ -514,10 +504,8 @@
snp_drvinit(unused)
void *unused;
{
- int i;
- for (i = 0; i < NSNP; i++)
- make_dev(&snp_cdevsw, i, 0, 0, 0600, "snp%d", i);
+ cdevsw_add(&snp_cdevsw);
}
SYSINIT(snpdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,snp_drvinit,NULL)
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