freebsd-skq/sys/coda/coda_fbsd.c
rwatson daa1c89f45 Merge the dev_clone and dev_clone_cred event handlers into a single
event handler, dev_clone, which accepts a credential argument.
Implementors of the event can ignore it if they're not interested,
and most do.  This avoids having multiple event handler types and
fall-back/precedence logic in devfs.

This changes the kernel API for /dev cloning, and may affect third
party packages containg cloning kernel modules.

Requested by:	phk
MFC after:	3 days
2005-08-08 19:55:32 +00:00

141 lines
3.7 KiB
C

/*-
* Coda: an Experimental Distributed File System
* Release 3.1
*
* Copyright (c) 1987-1998 Carnegie Mellon University
* All Rights Reserved
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation, and
* that credit is given to Carnegie Mellon University in all documents
* and publicity pertaining to direct or indirect use of this code or its
* derivatives.
*
* CODA IS AN EXPERIMENTAL SOFTWARE SYSTEM AND IS KNOWN TO HAVE BUGS,
* SOME OF WHICH MAY HAVE SERIOUS CONSEQUENCES. CARNEGIE MELLON ALLOWS
* FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION. CARNEGIE MELLON
* DISCLAIMS ANY LIABILITY OF ANY KIND FOR ANY DAMAGES WHATSOEVER
* RESULTING DIRECTLY OR INDIRECTLY FROM THE USE OF THIS SOFTWARE OR OF
* ANY DERIVATIVE WORK.
*
* Carnegie Mellon encourages users of this software to return any
* improvements or extensions that they make, and to grant Carnegie
* Mellon the rights to redistribute these changes without encumbrance.
*
* @(#) src/sys/coda/coda_fbsd.cr,v 1.1.1.1 1998/08/29 21:14:52 rvb Exp $
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/ucred.h>
#include <sys/vnode.h>
#include <vm/vm.h>
#include <vm/vnode_pager.h>
#include <coda/coda.h>
#include <coda/cnode.h>
#include <coda/coda_vnops.h>
#include <coda/coda_psdev.h>
static struct cdevsw codadevsw = {
.d_version = D_VERSION,
.d_flags = D_NEEDGIANT,
.d_open = vc_nb_open,
.d_close = vc_nb_close,
.d_read = vc_nb_read,
.d_write = vc_nb_write,
.d_ioctl = vc_nb_ioctl,
.d_poll = vc_nb_poll,
.d_name = "Coda",
};
static eventhandler_tag clonetag;
static LIST_HEAD(, coda_mntinfo) coda_mnttbl;
int vcdebug = 1;
#define VCDEBUG if (vcdebug) printf
/* for DEVFS, using bpf & tun drivers as examples*/
static void coda_fbsd_clone(void *arg, struct ucred *cred, char *name,
int namelen, struct cdev **dev);
static int
codadev_modevent(module_t mod, int type, void *data)
{
struct coda_mntinfo *mnt;
switch (type) {
case MOD_LOAD:
LIST_INIT(&coda_mnttbl);
clonetag = EVENTHANDLER_REGISTER(dev_clone, coda_fbsd_clone,
0, 1000);
break;
case MOD_UNLOAD:
EVENTHANDLER_DEREGISTER(dev_clone, clonetag);
while ((mnt = LIST_FIRST(&coda_mnttbl)) != NULL) {
LIST_REMOVE(mnt, mi_list);
destroy_dev(mnt->dev);
free(mnt, M_CODA);
}
break;
default:
return (EOPNOTSUPP);
}
return 0;
}
static moduledata_t codadev_mod = {
"codadev",
codadev_modevent,
NULL
};
DECLARE_MODULE(codadev, codadev_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
static void coda_fbsd_clone(arg, cred, name, namelen, dev)
void *arg;
struct ucred *cred;
char *name;
int namelen;
struct cdev **dev;
{
int u;
struct coda_mntinfo *mnt;
if (*dev != NULL)
return;
if (dev_stdclone(name,NULL,"cfs",&u) != 1)
return;
*dev = make_dev(&codadevsw,unit2minor(u),UID_ROOT,GID_WHEEL,0600,"cfs%d",u);
dev_ref(*dev);
mnt = malloc(sizeof(struct coda_mntinfo), M_CODA, M_WAITOK|M_ZERO);
LIST_INSERT_HEAD(&coda_mnttbl, mnt, mi_list);
}
struct coda_mntinfo *
dev2coda_mntinfo(struct cdev *dev)
{
struct coda_mntinfo *mnt;
LIST_FOREACH(mnt, &coda_mnttbl, mi_list) {
if (mnt->dev == dev)
break;
}
return mnt;
}