a1dc209638
administrator to define certain properties of new devfs nodes before they become visible to the userland. Both static (e.g., /dev/speaker) and dynamic (e.g., /dev/bpf*, some removable devices) nodes are supported. Each DEVFS mount may have a different ruleset assigned to it, permitting different policies to be implemented for things like jails. Approved by: phk
445 lines
10 KiB
C
445 lines
10 KiB
C
#define DEBUG 1
|
|
/*
|
|
* Copyright (c) 2000
|
|
* Poul-Henning Kamp. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* From: FreeBSD: src/sys/miscfs/kernfs/kernfs_vfsops.c 1.36
|
|
*
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include "opt_devfs.h"
|
|
#ifndef NODEVFS
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/conf.h>
|
|
#include <sys/dirent.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/vnode.h>
|
|
|
|
#include <machine/atomic.h>
|
|
|
|
#include <fs/devfs/devfs.h>
|
|
|
|
static dev_t devfs_inot[NDEVFSINO];
|
|
static dev_t *devfs_overflow;
|
|
static int devfs_ref[NDEVFSINO];
|
|
static int *devfs_refoverflow;
|
|
static int devfs_nextino = 3;
|
|
static int devfs_numino;
|
|
static int devfs_topino;
|
|
static int devfs_noverflowwant = NDEVFSOVERFLOW;
|
|
static int devfs_noverflow;
|
|
static unsigned devfs_generation;
|
|
|
|
static void devfs_attemptoverflow(int insist);
|
|
static struct devfs_dirent *devfs_find (struct devfs_dirent *dd, const char *name, int namelen);
|
|
|
|
SYSCTL_NODE(_vfs, OID_AUTO, devfs, CTLFLAG_RW, 0, "DEVFS filesystem");
|
|
SYSCTL_UINT(_vfs_devfs, OID_AUTO, noverflow, CTLFLAG_RW,
|
|
&devfs_noverflowwant, 0, "Size of DEVFS overflow table");
|
|
SYSCTL_UINT(_vfs_devfs, OID_AUTO, generation, CTLFLAG_RD,
|
|
&devfs_generation, 0, "DEVFS generation number");
|
|
SYSCTL_UINT(_vfs_devfs, OID_AUTO, inodes, CTLFLAG_RD,
|
|
&devfs_numino, 0, "DEVFS inodes");
|
|
SYSCTL_UINT(_vfs_devfs, OID_AUTO, topinode, CTLFLAG_RD,
|
|
&devfs_topino, 0, "DEVFS highest inode#");
|
|
|
|
static int *
|
|
devfs_itor(int inode)
|
|
{
|
|
if (inode < NDEVFSINO)
|
|
return (&devfs_ref[inode]);
|
|
else if (inode < NDEVFSINO + devfs_noverflow)
|
|
return (&devfs_refoverflow[inode - NDEVFSINO]);
|
|
else
|
|
panic ("YRK!");
|
|
}
|
|
|
|
static void
|
|
devfs_dropref(int inode)
|
|
{
|
|
int *ip;
|
|
|
|
ip = devfs_itor(inode);
|
|
atomic_add_int(ip, -1);
|
|
}
|
|
|
|
static int
|
|
devfs_getref(int inode)
|
|
{
|
|
int *ip, i, j;
|
|
dev_t *dp;
|
|
|
|
ip = devfs_itor(inode);
|
|
dp = devfs_itod(inode);
|
|
for (;;) {
|
|
i = *ip;
|
|
j = i + 1;
|
|
if (!atomic_cmpset_int(ip, i, j))
|
|
continue;
|
|
if (*dp != NULL)
|
|
return (1);
|
|
atomic_add_int(ip, -1);
|
|
return(0);
|
|
}
|
|
}
|
|
|
|
struct devfs_dirent **
|
|
devfs_itode (struct devfs_mount *dm, int inode)
|
|
{
|
|
|
|
if (inode < NDEVFSINO)
|
|
return (&dm->dm_dirent[inode]);
|
|
if (devfs_overflow == NULL)
|
|
return (NULL);
|
|
if (inode < NDEVFSINO + devfs_noverflow)
|
|
return (&dm->dm_overflow[inode - NDEVFSINO]);
|
|
return (NULL);
|
|
}
|
|
|
|
dev_t *
|
|
devfs_itod (int inode)
|
|
{
|
|
|
|
if (inode < NDEVFSINO)
|
|
return (&devfs_inot[inode]);
|
|
if (devfs_overflow == NULL)
|
|
return (NULL);
|
|
if (inode < NDEVFSINO + devfs_noverflow)
|
|
return (&devfs_overflow[inode - NDEVFSINO]);
|
|
return (NULL);
|
|
}
|
|
|
|
static void
|
|
devfs_attemptoverflow(int insist)
|
|
{
|
|
dev_t **ot;
|
|
int *or;
|
|
int n, nb;
|
|
|
|
/* Check if somebody beat us to it */
|
|
if (devfs_overflow != NULL)
|
|
return;
|
|
ot = NULL;
|
|
or = NULL;
|
|
n = devfs_noverflowwant;
|
|
nb = sizeof (struct dev_t *) * n;
|
|
MALLOC(ot, dev_t **, nb, M_DEVFS, (insist ? M_WAITOK : M_NOWAIT) | M_ZERO);
|
|
if (ot == NULL)
|
|
goto bail;
|
|
nb = sizeof (int) * n;
|
|
MALLOC(or, int *, nb, M_DEVFS, (insist ? M_WAITOK : M_NOWAIT) | M_ZERO);
|
|
if (or == NULL)
|
|
goto bail;
|
|
if (!atomic_cmpset_ptr(&devfs_overflow, NULL, ot))
|
|
goto bail;
|
|
devfs_refoverflow = or;
|
|
devfs_noverflow = n;
|
|
printf("DEVFS Overflow table with %d entries allocated when %d in use\n", n, devfs_numino);
|
|
return;
|
|
|
|
bail:
|
|
/* Somebody beat us to it, or something went wrong. */
|
|
if (ot != NULL)
|
|
FREE(ot, M_DEVFS);
|
|
if (or != NULL)
|
|
FREE(or, M_DEVFS);
|
|
return;
|
|
}
|
|
|
|
static struct devfs_dirent *
|
|
devfs_find(struct devfs_dirent *dd, const char *name, int namelen)
|
|
{
|
|
struct devfs_dirent *de;
|
|
|
|
TAILQ_FOREACH(de, &dd->de_dlist, de_list) {
|
|
if (namelen != de->de_dirent->d_namlen)
|
|
continue;
|
|
if (bcmp(name, de->de_dirent->d_name, namelen) != 0)
|
|
continue;
|
|
break;
|
|
}
|
|
return (de);
|
|
}
|
|
|
|
struct devfs_dirent *
|
|
devfs_newdirent(char *name, int namelen)
|
|
{
|
|
int i;
|
|
struct devfs_dirent *de;
|
|
struct dirent d;
|
|
|
|
d.d_namlen = namelen;
|
|
i = sizeof (*de) + GENERIC_DIRSIZ(&d);
|
|
MALLOC(de, struct devfs_dirent *, i, M_DEVFS, M_WAITOK | M_ZERO);
|
|
de->de_dirent = (struct dirent *)(de + 1);
|
|
de->de_dirent->d_namlen = namelen;
|
|
de->de_dirent->d_reclen = GENERIC_DIRSIZ(&d);
|
|
bcopy(name, de->de_dirent->d_name, namelen);
|
|
de->de_dirent->d_name[namelen] = '\0';
|
|
vfs_timestamp(&de->de_ctime);
|
|
de->de_mtime = de->de_atime = de->de_ctime;
|
|
de->de_links = 1;
|
|
return (de);
|
|
}
|
|
|
|
struct devfs_dirent *
|
|
devfs_vmkdir(char *name, int namelen, struct devfs_dirent *dotdot)
|
|
{
|
|
struct devfs_dirent *dd;
|
|
struct devfs_dirent *de;
|
|
|
|
dd = devfs_newdirent(name, namelen);
|
|
|
|
TAILQ_INIT(&dd->de_dlist);
|
|
|
|
dd->de_dirent->d_type = DT_DIR;
|
|
dd->de_mode = 0555;
|
|
dd->de_links = 2;
|
|
dd->de_dir = dd;
|
|
|
|
de = devfs_newdirent(".", 1);
|
|
de->de_dirent->d_type = DT_DIR;
|
|
de->de_dir = dd;
|
|
de->de_flags |= DE_DOT;
|
|
TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
|
|
|
|
de = devfs_newdirent("..", 2);
|
|
de->de_dirent->d_type = DT_DIR;
|
|
if (dotdot == NULL)
|
|
de->de_dir = dd;
|
|
else
|
|
de->de_dir = dotdot;
|
|
de->de_flags |= DE_DOTDOT;
|
|
TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
|
|
|
|
return (dd);
|
|
}
|
|
|
|
static void
|
|
devfs_delete(struct devfs_dirent *dd, struct devfs_dirent *de)
|
|
{
|
|
|
|
if (de->de_symlink) {
|
|
FREE(de->de_symlink, M_DEVFS);
|
|
de->de_symlink = NULL;
|
|
}
|
|
if (de->de_vnode)
|
|
de->de_vnode->v_data = NULL;
|
|
TAILQ_REMOVE(&dd->de_dlist, de, de_list);
|
|
FREE(de, M_DEVFS);
|
|
}
|
|
|
|
void
|
|
devfs_purge(struct devfs_dirent *dd)
|
|
{
|
|
struct devfs_dirent *de;
|
|
|
|
for (;;) {
|
|
de = TAILQ_FIRST(&dd->de_dlist);
|
|
if (de == NULL)
|
|
break;
|
|
devfs_delete(dd, de);
|
|
}
|
|
FREE(dd, M_DEVFS);
|
|
}
|
|
|
|
|
|
int
|
|
devfs_populate(struct devfs_mount *dm)
|
|
{
|
|
int i, j;
|
|
dev_t dev, pdev;
|
|
struct devfs_dirent *dd;
|
|
struct devfs_dirent *de, **dep;
|
|
char *q, *s;
|
|
|
|
if (dm->dm_generation == devfs_generation)
|
|
return (0);
|
|
lockmgr(&dm->dm_lock, LK_UPGRADE, 0, curthread);
|
|
if (devfs_noverflow && dm->dm_overflow == NULL) {
|
|
i = devfs_noverflow * sizeof (struct devfs_dirent *);
|
|
MALLOC(dm->dm_overflow, struct devfs_dirent **, i,
|
|
M_DEVFS, M_WAITOK | M_ZERO);
|
|
}
|
|
while (dm->dm_generation != devfs_generation) {
|
|
dm->dm_generation = devfs_generation;
|
|
for (i = 0; i <= devfs_topino; i++) {
|
|
dev = *devfs_itod(i);
|
|
dep = devfs_itode(dm, i);
|
|
de = *dep;
|
|
if (dev == NULL && de == DE_DELETED) {
|
|
*dep = NULL;
|
|
continue;
|
|
}
|
|
if (dev == NULL && de != NULL) {
|
|
dd = de->de_dir;
|
|
*dep = NULL;
|
|
TAILQ_REMOVE(&dd->de_dlist, de, de_list);
|
|
if (de->de_vnode)
|
|
de->de_vnode->v_data = NULL;
|
|
FREE(de, M_DEVFS);
|
|
devfs_dropref(i);
|
|
continue;
|
|
}
|
|
if (dev == NULL)
|
|
continue;
|
|
if (de != NULL)
|
|
continue;
|
|
if (!devfs_getref(i))
|
|
continue;
|
|
dd = dm->dm_basedir;
|
|
s = dev->si_name;
|
|
for (;;) {
|
|
for (q = s; *q != '/' && *q != '\0'; q++)
|
|
continue;
|
|
if (*q != '/')
|
|
break;
|
|
de = devfs_find(dd, s, q - s);
|
|
if (de == NULL) {
|
|
de = devfs_vmkdir(s, q - s, dd);
|
|
de->de_inode = dm->dm_inode++;
|
|
TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
|
|
dd->de_links++;
|
|
}
|
|
s = q + 1;
|
|
dd = de;
|
|
}
|
|
de = devfs_newdirent(s, q - s);
|
|
if (dev->si_flags & SI_ALIAS) {
|
|
de->de_inode = dm->dm_inode++;
|
|
de->de_uid = 0;
|
|
de->de_gid = 0;
|
|
de->de_mode = 0755;
|
|
de->de_dirent->d_type = DT_LNK;
|
|
pdev = dev->si_parent;
|
|
j = strlen(pdev->si_name) + 1;
|
|
MALLOC(de->de_symlink, char *, j, M_DEVFS, M_WAITOK);
|
|
bcopy(pdev->si_name, de->de_symlink, j);
|
|
} else {
|
|
de->de_inode = i;
|
|
de->de_uid = dev->si_uid;
|
|
de->de_gid = dev->si_gid;
|
|
de->de_mode = dev->si_mode;
|
|
de->de_dirent->d_type = DT_CHR;
|
|
}
|
|
*dep = de;
|
|
de->de_dir = dd;
|
|
devfs_rules_apply(dm, de);
|
|
TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list);
|
|
#if 0
|
|
printf("Add ino%d %s\n", i, dev->si_name);
|
|
#endif
|
|
}
|
|
}
|
|
lockmgr(&dm->dm_lock, LK_DOWNGRADE, 0, curthread);
|
|
return (0);
|
|
}
|
|
|
|
static void
|
|
devfs_create(dev_t dev)
|
|
{
|
|
int ino, i, *ip;
|
|
dev_t *dp;
|
|
|
|
for (;;) {
|
|
/* Grab the next inode number */
|
|
ino = devfs_nextino;
|
|
i = ino + 1;
|
|
/* wrap around when we reach the end */
|
|
if (i >= NDEVFSINO + devfs_noverflow)
|
|
i = 3;
|
|
if (!atomic_cmpset_int(&devfs_nextino, ino, i))
|
|
continue;
|
|
|
|
/* see if it was occupied */
|
|
dp = devfs_itod(ino);
|
|
if (dp == NULL)
|
|
Debugger("dp == NULL\n");
|
|
if (*dp != NULL)
|
|
continue;
|
|
ip = devfs_itor(ino);
|
|
if (ip == NULL)
|
|
Debugger("ip == NULL\n");
|
|
if (*ip != 0)
|
|
continue;
|
|
|
|
if (!atomic_cmpset_ptr(dp, NULL, dev))
|
|
continue;
|
|
|
|
dev->si_inode = ino;
|
|
for (;;) {
|
|
i = devfs_topino;
|
|
if (i >= ino)
|
|
break;
|
|
if (atomic_cmpset_int(&devfs_topino, i, ino))
|
|
break;
|
|
printf("failed topino %d %d\n", i, ino);
|
|
}
|
|
break;
|
|
}
|
|
|
|
atomic_add_int(&devfs_numino, 1);
|
|
atomic_add_int(&devfs_generation, 1);
|
|
if (devfs_overflow == NULL && devfs_numino + 100 > NDEVFSINO)
|
|
devfs_attemptoverflow(0);
|
|
}
|
|
|
|
static void
|
|
devfs_destroy(dev_t dev)
|
|
{
|
|
int ino, i;
|
|
|
|
ino = dev->si_inode;
|
|
dev->si_inode = 0;
|
|
if (ino == 0)
|
|
return;
|
|
if (atomic_cmpset_ptr(devfs_itod(ino), dev, NULL)) {
|
|
atomic_add_int(&devfs_generation, 1);
|
|
atomic_add_int(&devfs_numino, -1);
|
|
i = devfs_nextino;
|
|
if (ino < i)
|
|
atomic_cmpset_int(&devfs_nextino, i, ino);
|
|
}
|
|
}
|
|
|
|
static void
|
|
devfs_init(void *junk)
|
|
{
|
|
devfs_create_hook = devfs_create;
|
|
devfs_destroy_hook = devfs_destroy;
|
|
devfs_present = 1;
|
|
devfs_rules_init();
|
|
}
|
|
|
|
SYSINIT(devfs, SI_SUB_DEVFS, SI_ORDER_FIRST, devfs_init, NULL);
|
|
|
|
#endif
|