freebsd-dev/sys/dev/sound/pcm/sndstat.c
Pyun YongHyeon 005a5d42fa Fix module unload panic which was caused by missing sx lock release.
While I'm here add KASSERT(9) to notify failure of SYSUNINIT handler.

Reported by:	Ben Kaduk < minimarmot AT gmail DOT com >
Tested by:	Ben Kaduk < minimarmot AT gmail DOT com >
2005-09-14 01:34:13 +00:00

401 lines
8.6 KiB
C

/*-
* Copyright (c) 2001 Cameron Grant <cg@freebsd.org>
* 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 <dev/sound/pcm/sound.h>
#include <dev/sound/pcm/vchan.h>
#ifdef USING_MUTEX
#include <sys/sx.h>
#endif
SND_DECLARE_FILE("$FreeBSD$");
#define SS_TYPE_MODULE 0
#define SS_TYPE_FIRST 1
#define SS_TYPE_PCM 1
#define SS_TYPE_MIDI 2
#define SS_TYPE_SEQUENCER 3
#define SS_TYPE_LAST 3
static d_open_t sndstat_open;
static d_close_t sndstat_close;
static d_read_t sndstat_read;
static struct cdevsw sndstat_cdevsw = {
.d_version = D_VERSION,
.d_flags = D_NEEDGIANT,
.d_open = sndstat_open,
.d_close = sndstat_close,
.d_read = sndstat_read,
.d_name = "sndstat",
};
struct sndstat_entry {
SLIST_ENTRY(sndstat_entry) link;
device_t dev;
char *str;
sndstat_handler handler;
int type, unit;
};
#ifdef USING_MUTEX
static struct sx sndstat_lock;
#endif
static struct sbuf sndstat_sbuf;
static struct cdev *sndstat_dev = 0;
static int sndstat_isopen = 0;
static int sndstat_bufptr;
static int sndstat_maxunit = -1;
static int sndstat_files = 0;
static SLIST_HEAD(, sndstat_entry) sndstat_devlist = SLIST_HEAD_INITIALIZER(none);
static int sndstat_verbose = 1;
#ifdef USING_MUTEX
TUNABLE_INT("hw.snd.verbose", &sndstat_verbose);
#else
TUNABLE_INT_DECL("hw.snd.verbose", 1, sndstat_verbose);
#endif
static int sndstat_prepare(struct sbuf *s);
static int
sysctl_hw_sndverbose(SYSCTL_HANDLER_ARGS)
{
intrmask_t s;
int error, verbose;
verbose = sndstat_verbose;
error = sysctl_handle_int(oidp, &verbose, sizeof(verbose), req);
if (error == 0 && req->newptr != NULL) {
s = spltty();
sx_xlock(&sndstat_lock);
if (verbose < 0 || verbose > 3)
error = EINVAL;
else
sndstat_verbose = verbose;
sx_xunlock(&sndstat_lock);
splx(s);
}
return error;
}
SYSCTL_PROC(_hw_snd, OID_AUTO, verbose, CTLTYPE_INT | CTLFLAG_RW,
0, sizeof(int), sysctl_hw_sndverbose, "I", "");
static int
sndstat_open(struct cdev *i_dev, int flags, int mode, struct thread *td)
{
intrmask_t s;
int error;
s = spltty();
sx_xlock(&sndstat_lock);
if (sndstat_isopen) {
sx_xunlock(&sndstat_lock);
splx(s);
return EBUSY;
}
sndstat_isopen = 1;
sx_xunlock(&sndstat_lock);
splx(s);
if (sbuf_new(&sndstat_sbuf, NULL, 4096, 0) == NULL) {
error = ENXIO;
goto out;
}
sndstat_bufptr = 0;
error = (sndstat_prepare(&sndstat_sbuf) > 0) ? 0 : ENOMEM;
out:
if (error) {
s = spltty();
sx_xlock(&sndstat_lock);
sndstat_isopen = 0;
sx_xunlock(&sndstat_lock);
splx(s);
}
return (error);
}
static int
sndstat_close(struct cdev *i_dev, int flags, int mode, struct thread *td)
{
intrmask_t s;
s = spltty();
sx_xlock(&sndstat_lock);
if (!sndstat_isopen) {
sx_xunlock(&sndstat_lock);
splx(s);
return EBADF;
}
sbuf_delete(&sndstat_sbuf);
sndstat_isopen = 0;
sx_xunlock(&sndstat_lock);
splx(s);
return 0;
}
static int
sndstat_read(struct cdev *i_dev, struct uio *buf, int flag)
{
intrmask_t s;
int l, err;
s = spltty();
sx_xlock(&sndstat_lock);
if (!sndstat_isopen) {
sx_xunlock(&sndstat_lock);
splx(s);
return EBADF;
}
l = min(buf->uio_resid, sbuf_len(&sndstat_sbuf) - sndstat_bufptr);
err = (l > 0)? uiomove(sbuf_data(&sndstat_sbuf) + sndstat_bufptr, l, buf) : 0;
sndstat_bufptr += l;
sx_xunlock(&sndstat_lock);
splx(s);
return err;
}
/************************************************************************/
static struct sndstat_entry *
sndstat_find(int type, int unit)
{
struct sndstat_entry *ent;
SLIST_FOREACH(ent, &sndstat_devlist, link) {
if (ent->type == type && ent->unit == unit)
return ent;
}
return NULL;
}
int
sndstat_register(device_t dev, char *str, sndstat_handler handler)
{
intrmask_t s;
struct sndstat_entry *ent;
const char *devtype;
int type, unit;
if (dev) {
unit = device_get_unit(dev);
devtype = device_get_name(dev);
if (!strcmp(devtype, "pcm"))
type = SS_TYPE_PCM;
else if (!strcmp(devtype, "midi"))
type = SS_TYPE_MIDI;
else if (!strcmp(devtype, "sequencer"))
type = SS_TYPE_SEQUENCER;
else
return EINVAL;
} else {
type = SS_TYPE_MODULE;
unit = -1;
}
ent = malloc(sizeof *ent, M_DEVBUF, M_ZERO | M_WAITOK);
if (!ent)
return ENOSPC;
ent->dev = dev;
ent->str = str;
ent->type = type;
ent->unit = unit;
ent->handler = handler;
s = spltty();
sx_xlock(&sndstat_lock);
SLIST_INSERT_HEAD(&sndstat_devlist, ent, link);
if (type == SS_TYPE_MODULE)
sndstat_files++;
sndstat_maxunit = (unit > sndstat_maxunit)? unit : sndstat_maxunit;
sx_xunlock(&sndstat_lock);
splx(s);
return 0;
}
int
sndstat_registerfile(char *str)
{
return sndstat_register(NULL, str, NULL);
}
int
sndstat_unregister(device_t dev)
{
intrmask_t s;
struct sndstat_entry *ent;
s = spltty();
sx_xlock(&sndstat_lock);
SLIST_FOREACH(ent, &sndstat_devlist, link) {
if (ent->dev == dev) {
SLIST_REMOVE(&sndstat_devlist, ent, sndstat_entry, link);
sx_xunlock(&sndstat_lock);
splx(s);
free(ent, M_DEVBUF);
return 0;
}
}
sx_xunlock(&sndstat_lock);
splx(s);
return ENXIO;
}
int
sndstat_unregisterfile(char *str)
{
intrmask_t s;
struct sndstat_entry *ent;
s = spltty();
sx_xlock(&sndstat_lock);
SLIST_FOREACH(ent, &sndstat_devlist, link) {
if (ent->dev == NULL && ent->str == str) {
SLIST_REMOVE(&sndstat_devlist, ent, sndstat_entry, link);
sndstat_files--;
sx_xunlock(&sndstat_lock);
splx(s);
free(ent, M_DEVBUF);
return 0;
}
}
sx_xunlock(&sndstat_lock);
splx(s);
return ENXIO;
}
/************************************************************************/
static int
sndstat_prepare(struct sbuf *s)
{
struct sndstat_entry *ent;
int i, j;
sbuf_printf(s, "FreeBSD Audio Driver (newpcm)\n");
if (SLIST_EMPTY(&sndstat_devlist)) {
sbuf_printf(s, "No devices installed.\n");
sbuf_finish(s);
return sbuf_len(s);
}
sbuf_printf(s, "Installed devices:\n");
for (i = 0; i <= sndstat_maxunit; i++) {
for (j = SS_TYPE_FIRST; j <= SS_TYPE_LAST; j++) {
ent = sndstat_find(j, i);
if (!ent)
continue;
sbuf_printf(s, "%s:", device_get_nameunit(ent->dev));
sbuf_printf(s, " <%s>", device_get_desc(ent->dev));
sbuf_printf(s, " %s", ent->str);
if (ent->handler)
ent->handler(s, ent->dev, sndstat_verbose);
else
sbuf_printf(s, " [no handler]");
sbuf_printf(s, "\n");
}
}
if (sndstat_verbose >= 3 && sndstat_files > 0) {
sbuf_printf(s, "\nFile Versions:\n");
SLIST_FOREACH(ent, &sndstat_devlist, link) {
if (ent->dev == NULL && ent->str != NULL)
sbuf_printf(s, "%s\n", ent->str);
}
}
sbuf_finish(s);
return sbuf_len(s);
}
static int
sndstat_init(void)
{
sx_init(&sndstat_lock, "sndstat");
sndstat_dev = make_dev(&sndstat_cdevsw, SND_DEV_STATUS, UID_ROOT, GID_WHEEL, 0444, "sndstat");
return (sndstat_dev != 0)? 0 : ENXIO;
}
static int
sndstat_uninit(void)
{
intrmask_t s;
s = spltty();
sx_xlock(&sndstat_lock);
if (sndstat_isopen) {
sx_xunlock(&sndstat_lock);
splx(s);
return EBUSY;
}
if (sndstat_dev)
destroy_dev(sndstat_dev);
sndstat_dev = 0;
splx(s);
sx_xunlock(&sndstat_lock);
sx_destroy(&sndstat_lock);
return 0;
}
int
sndstat_busy(void)
{
return (sndstat_isopen);
}
static void
sndstat_sysinit(void *p)
{
sndstat_init();
}
static void
sndstat_sysuninit(void *p)
{
int error;
error = sndstat_uninit();
KASSERT(error == 0, ("%s: error = %d", __func__, error));
}
SYSINIT(sndstat_sysinit, SI_SUB_DRIVERS, SI_ORDER_FIRST, sndstat_sysinit, NULL);
SYSUNINIT(sndstat_sysuninit, SI_SUB_DRIVERS, SI_ORDER_FIRST, sndstat_sysuninit, NULL);