NetBSD/sys/kern/kern_drvctl.c

571 lines
13 KiB
C

/* $NetBSD: kern_drvctl.c,v 1.32 2011/08/31 18:31:02 plunky Exp $ */
/*
* Copyright (c) 2004
* Matthias Drochner. 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. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: kern_drvctl.c,v 1.32 2011/08/31 18:31:02 plunky Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/event.h>
#include <sys/kmem.h>
#include <sys/ioctl.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/select.h>
#include <sys/poll.h>
#include <sys/drvctlio.h>
#include <sys/devmon.h>
#include <sys/stat.h>
#include <sys/kauth.h>
#include <sys/lwp.h>
struct drvctl_event {
TAILQ_ENTRY(drvctl_event) dce_link;
prop_dictionary_t dce_event;
};
TAILQ_HEAD(drvctl_queue, drvctl_event);
static struct drvctl_queue drvctl_eventq; /* FIFO */
static kcondvar_t drvctl_cond;
static kmutex_t drvctl_lock;
static int drvctl_nopen = 0, drvctl_eventcnt = 0;
static struct selinfo drvctl_rdsel;
#define DRVCTL_EVENTQ_DEPTH 64 /* arbitrary queue limit */
dev_type_open(drvctlopen);
const struct cdevsw drvctl_cdevsw = {
drvctlopen, nullclose, nullread, nullwrite, noioctl,
nostop, notty, nopoll, nommap, nokqfilter, D_OTHER
};
void drvctlattach(int);
static int drvctl_read(struct file *, off_t *, struct uio *,
kauth_cred_t, int);
static int drvctl_write(struct file *, off_t *, struct uio *,
kauth_cred_t, int);
static int drvctl_ioctl(struct file *, u_long, void *);
static int drvctl_poll(struct file *, int);
static int drvctl_stat(struct file *, struct stat *);
static int drvctl_close(struct file *);
static const struct fileops drvctl_fileops = {
.fo_read = drvctl_read,
.fo_write = drvctl_write,
.fo_ioctl = drvctl_ioctl,
.fo_fcntl = fnullop_fcntl,
.fo_poll = drvctl_poll,
.fo_stat = drvctl_stat,
.fo_close = drvctl_close,
.fo_kqfilter = fnullop_kqfilter,
.fo_restart = fnullop_restart,
};
#define MAXLOCATORS 100
static int drvctl_command(struct lwp *, struct plistref *, u_long, int);
static int drvctl_getevent(struct lwp *, struct plistref *, u_long, int);
void
drvctl_init(void)
{
TAILQ_INIT(&drvctl_eventq);
mutex_init(&drvctl_lock, MUTEX_DEFAULT, IPL_NONE);
cv_init(&drvctl_cond, "devmon");
selinit(&drvctl_rdsel);
}
void
devmon_insert(const char *event, prop_dictionary_t ev)
{
struct drvctl_event *dce, *odce;
mutex_enter(&drvctl_lock);
if (drvctl_nopen == 0) {
mutex_exit(&drvctl_lock);
return;
}
/* Fill in mandatory member */
if (!prop_dictionary_set_cstring_nocopy(ev, "event", event)) {
prop_object_release(ev);
mutex_exit(&drvctl_lock);
return;
}
dce = kmem_alloc(sizeof(*dce), KM_SLEEP);
if (dce == NULL) {
mutex_exit(&drvctl_lock);
return;
}
dce->dce_event = ev;
if (drvctl_eventcnt == DRVCTL_EVENTQ_DEPTH) {
odce = TAILQ_FIRST(&drvctl_eventq);
TAILQ_REMOVE(&drvctl_eventq, odce, dce_link);
prop_object_release(odce->dce_event);
kmem_free(odce, sizeof(*odce));
--drvctl_eventcnt;
}
TAILQ_INSERT_TAIL(&drvctl_eventq, dce, dce_link);
++drvctl_eventcnt;
cv_broadcast(&drvctl_cond);
selnotify(&drvctl_rdsel, 0, 0);
mutex_exit(&drvctl_lock);
}
int
drvctlopen(dev_t dev, int flags, int mode, struct lwp *l)
{
struct file *fp;
int fd;
int ret;
ret = fd_allocfile(&fp, &fd);
if (ret)
return ret;
/* XXX setup context */
mutex_enter(&drvctl_lock);
ret = fd_clone(fp, fd, flags, &drvctl_fileops, /* context */NULL);
++drvctl_nopen;
mutex_exit(&drvctl_lock);
return ret;
}
static int
pmdevbyname(u_long cmd, struct devpmargs *a)
{
struct device *d;
if ((d = device_find_by_xname(a->devname)) == NULL)
return ENXIO;
switch (cmd) {
case DRVSUSPENDDEV:
return pmf_device_recursive_suspend(d, PMF_Q_DRVCTL) ? 0 : EBUSY;
case DRVRESUMEDEV:
if (a->flags & DEVPM_F_SUBTREE) {
return pmf_device_subtree_resume(d, PMF_Q_DRVCTL)
? 0 : EBUSY;
} else {
return pmf_device_recursive_resume(d, PMF_Q_DRVCTL)
? 0 : EBUSY;
}
default:
return EPASSTHROUGH;
}
}
static int
listdevbyname(struct devlistargs *l)
{
device_t d, child;
deviter_t di;
int cnt = 0, idx, error = 0;
if (*l->l_devname == '\0')
d = NULL;
else if (memchr(l->l_devname, 0, sizeof(l->l_devname)) == NULL)
return EINVAL;
else if ((d = device_find_by_xname(l->l_devname)) == NULL)
return ENXIO;
for (child = deviter_first(&di, 0); child != NULL;
child = deviter_next(&di)) {
if (device_parent(child) != d)
continue;
idx = cnt++;
if (l->l_childname == NULL || idx >= l->l_children)
continue;
error = copyoutstr(device_xname(child), l->l_childname[idx],
sizeof(l->l_childname[idx]), NULL);
if (error != 0)
break;
}
deviter_release(&di);
l->l_children = cnt;
return error;
}
static int
detachdevbyname(const char *devname)
{
struct device *d;
if ((d = device_find_by_xname(devname)) == NULL)
return ENXIO;
#ifndef XXXFULLRISK
/*
* If the parent cannot be notified, it might keep
* pointers to the detached device.
* There might be a private notification mechanism,
* but better play it safe here.
*/
if (d->dv_parent && !d->dv_parent->dv_cfattach->ca_childdetached)
return ENOTSUP;
#endif
return config_detach(d, 0);
}
static int
rescanbus(const char *busname, const char *ifattr,
int numlocators, const int *locators)
{
int i, rc;
struct device *d;
const struct cfiattrdata * const *ap;
/* XXX there should be a way to get limits and defaults (per device)
from config generated data */
int locs[MAXLOCATORS];
for (i = 0; i < MAXLOCATORS; i++)
locs[i] = -1;
for (i = 0; i < numlocators;i++)
locs[i] = locators[i];
if ((d = device_find_by_xname(busname)) == NULL)
return ENXIO;
/*
* must support rescan, and must have something
* to attach to
*/
if (!d->dv_cfattach->ca_rescan ||
!d->dv_cfdriver->cd_attrs)
return ENODEV;
/* allow to omit attribute if there is exactly one */
if (!ifattr) {
if (d->dv_cfdriver->cd_attrs[1])
return EINVAL;
ifattr = d->dv_cfdriver->cd_attrs[0]->ci_name;
} else {
/* check for valid attribute passed */
for (ap = d->dv_cfdriver->cd_attrs; *ap; ap++)
if (!strcmp((*ap)->ci_name, ifattr))
break;
if (!*ap)
return EINVAL;
}
rc = (*d->dv_cfattach->ca_rescan)(d, ifattr, locs);
config_deferred(NULL);
return rc;
}
static int
drvctl_read(struct file *fp, off_t *offp, struct uio *uio, kauth_cred_t cred,
int flags)
{
return ENODEV;
}
static int
drvctl_write(struct file *fp, off_t *offp, struct uio *uio, kauth_cred_t cred,
int flags)
{
return ENODEV;
}
static int
drvctl_ioctl(struct file *fp, u_long cmd, void *data)
{
int res;
char *ifattr;
int *locs;
size_t locs_sz = 0; /* XXXgcc */
switch (cmd) {
case DRVSUSPENDDEV:
case DRVRESUMEDEV:
#define d ((struct devpmargs *)data)
res = pmdevbyname(cmd, d);
#undef d
break;
case DRVLISTDEV:
res = listdevbyname((struct devlistargs *)data);
break;
case DRVDETACHDEV:
#define d ((struct devdetachargs *)data)
res = detachdevbyname(d->devname);
#undef d
break;
case DRVRESCANBUS:
#define d ((struct devrescanargs *)data)
d->busname[sizeof(d->busname) - 1] = '\0';
/* XXX better copyin? */
if (d->ifattr[0]) {
d->ifattr[sizeof(d->ifattr) - 1] = '\0';
ifattr = d->ifattr;
} else
ifattr = 0;
if (d->numlocators) {
if (d->numlocators > MAXLOCATORS)
return EINVAL;
locs_sz = d->numlocators * sizeof(int);
locs = kmem_alloc(locs_sz, KM_SLEEP);
res = copyin(d->locators, locs, locs_sz);
if (res) {
kmem_free(locs, locs_sz);
return res;
}
} else
locs = NULL;
res = rescanbus(d->busname, ifattr, d->numlocators, locs);
if (locs)
kmem_free(locs, locs_sz);
#undef d
break;
case DRVCTLCOMMAND:
res = drvctl_command(curlwp, (struct plistref *)data, cmd,
fp->f_flag);
break;
case DRVGETEVENT:
res = drvctl_getevent(curlwp, (struct plistref *)data, cmd,
fp->f_flag);
break;
default:
return EPASSTHROUGH;
}
return res;
}
static int
drvctl_stat(struct file *fp, struct stat *st)
{
(void)memset(st, 0, sizeof(*st));
st->st_uid = kauth_cred_geteuid(fp->f_cred);
st->st_gid = kauth_cred_getegid(fp->f_cred);
return 0;
}
static int
drvctl_poll(struct file *fp, int events)
{
int revents = 0;
if (!TAILQ_EMPTY(&drvctl_eventq))
revents |= events & (POLLIN | POLLRDNORM);
else
selrecord(curlwp, &drvctl_rdsel);
return revents;
}
static int
drvctl_close(struct file *fp)
{
struct drvctl_event *dce;
/* XXX free context */
mutex_enter(&drvctl_lock);
KASSERT(drvctl_nopen > 0);
--drvctl_nopen;
if (drvctl_nopen == 0) {
/* flush queue */
while ((dce = TAILQ_FIRST(&drvctl_eventq)) != NULL) {
TAILQ_REMOVE(&drvctl_eventq, dce, dce_link);
KASSERT(drvctl_eventcnt > 0);
--drvctl_eventcnt;
prop_object_release(dce->dce_event);
kmem_free(dce, sizeof(*dce));
}
}
mutex_exit(&drvctl_lock);
return 0;
}
void
drvctlattach(int arg)
{
}
/*****************************************************************************
* Driver control command processing engine
*****************************************************************************/
static int
drvctl_command_get_properties(struct lwp *l,
prop_dictionary_t command_dict,
prop_dictionary_t results_dict)
{
prop_dictionary_t args_dict;
prop_string_t devname_string;
device_t dev;
deviter_t di;
args_dict = prop_dictionary_get(command_dict, "drvctl-arguments");
if (args_dict == NULL)
return EINVAL;
devname_string = prop_dictionary_get(args_dict, "device-name");
if (devname_string == NULL)
return EINVAL;
for (dev = deviter_first(&di, 0); dev != NULL;
dev = deviter_next(&di)) {
if (prop_string_equals_cstring(devname_string,
device_xname(dev))) {
prop_dictionary_set(results_dict, "drvctl-result-data",
device_properties(dev));
break;
}
}
deviter_release(&di);
if (dev == NULL)
return ESRCH;
return 0;
}
struct drvctl_command_desc {
const char *dcd_name; /* command name */
int (*dcd_func)(struct lwp *, /* handler function */
prop_dictionary_t,
prop_dictionary_t);
int dcd_rw; /* read or write required */
};
static const struct drvctl_command_desc drvctl_command_table[] = {
{ .dcd_name = "get-properties",
.dcd_func = drvctl_command_get_properties,
.dcd_rw = FREAD,
},
{ .dcd_name = NULL }
};
static int
drvctl_command(struct lwp *l, struct plistref *pref, u_long ioctl_cmd,
int fflag)
{
prop_dictionary_t command_dict, results_dict;
prop_string_t command_string;
const struct drvctl_command_desc *dcd;
int error;
error = prop_dictionary_copyin_ioctl(pref, ioctl_cmd, &command_dict);
if (error)
return error;
results_dict = prop_dictionary_create();
if (results_dict == NULL) {
prop_object_release(command_dict);
return ENOMEM;
}
command_string = prop_dictionary_get(command_dict, "drvctl-command");
if (command_string == NULL) {
error = EINVAL;
goto out;
}
for (dcd = drvctl_command_table; dcd->dcd_name != NULL; dcd++) {
if (prop_string_equals_cstring(command_string,
dcd->dcd_name))
break;
}
if (dcd->dcd_name == NULL) {
error = EINVAL;
goto out;
}
if ((fflag & dcd->dcd_rw) == 0) {
error = EPERM;
goto out;
}
error = (*dcd->dcd_func)(l, command_dict, results_dict);
prop_dictionary_set_int32(results_dict, "drvctl-error", error);
error = prop_dictionary_copyout_ioctl(pref, ioctl_cmd, results_dict);
out:
prop_object_release(command_dict);
prop_object_release(results_dict);
return error;
}
static int
drvctl_getevent(struct lwp *l, struct plistref *pref, u_long ioctl_cmd,
int fflag)
{
struct drvctl_event *dce;
int ret;
if ((fflag & (FREAD|FWRITE)) != (FREAD|FWRITE))
return EPERM;
mutex_enter(&drvctl_lock);
while ((dce = TAILQ_FIRST(&drvctl_eventq)) == NULL) {
if (fflag & O_NONBLOCK) {
mutex_exit(&drvctl_lock);
return EWOULDBLOCK;
}
ret = cv_wait_sig(&drvctl_cond, &drvctl_lock);
if (ret) {
mutex_exit(&drvctl_lock);
return ret;
}
}
TAILQ_REMOVE(&drvctl_eventq, dce, dce_link);
KASSERT(drvctl_eventcnt > 0);
--drvctl_eventcnt;
mutex_exit(&drvctl_lock);
ret = prop_dictionary_copyout_ioctl(pref, ioctl_cmd, dce->dce_event);
prop_object_release(dce->dce_event);
kmem_free(dce, sizeof(*dce));
return ret;
}