freebsd-nq/sys/dev/sound/pcm/feeder.c
Brian Feldman 3fbe138ca9 It seems that sound(4)'s feeder routines don't need to allocate memory
without waiting, since they are called from a system-call context only.
This appears to fix all sorts of problems with open("/dev/dsp", O_WRONLY)
randomly returning ENXIO.

Found by:	cognet
2003-02-23 20:49:45 +00:00

426 lines
9.8 KiB
C

/*
* Copyright (c) 1999 Cameron Grant <gandalf@vilnya.demon.co.uk>
* 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 "feeder_if.h"
SND_DECLARE_FILE("$FreeBSD$");
MALLOC_DEFINE(M_FEEDER, "feeder", "pcm feeder");
#define MAXFEEDERS 256
#undef FEEDER_DEBUG
struct feedertab_entry {
SLIST_ENTRY(feedertab_entry) link;
struct feeder_class *feederclass;
struct pcm_feederdesc *desc;
int idx;
};
static SLIST_HEAD(, feedertab_entry) feedertab;
/*****************************************************************************/
void
feeder_register(void *p)
{
static int feedercnt = 0;
struct feeder_class *fc = p;
struct feedertab_entry *fte;
int i;
if (feedercnt == 0) {
KASSERT(fc->desc == NULL, ("first feeder not root: %s", fc->name));
SLIST_INIT(&feedertab);
fte = malloc(sizeof(*fte), M_FEEDER, M_WAITOK | M_ZERO);
if (fte == NULL) {
printf("can't allocate memory for root feeder: %s\n",
fc->name);
return;
}
fte->feederclass = fc;
fte->desc = NULL;
fte->idx = feedercnt;
SLIST_INSERT_HEAD(&feedertab, fte, link);
feedercnt++;
/* we've got our root feeder so don't veto pcm loading anymore */
pcm_veto_load = 0;
return;
}
KASSERT(fc->desc != NULL, ("feeder '%s' has no descriptor", fc->name));
/* beyond this point failure is non-fatal but may result in some translations being unavailable */
i = 0;
while ((feedercnt < MAXFEEDERS) && (fc->desc[i].type > 0)) {
/* printf("adding feeder %s, %x -> %x\n", fc->name, fc->desc[i].in, fc->desc[i].out); */
fte = malloc(sizeof(*fte), M_FEEDER, M_WAITOK | M_ZERO);
if (fte == NULL) {
printf("can't allocate memory for feeder '%s', %x -> %x\n", fc->name, fc->desc[i].in, fc->desc[i].out);
return;
}
fte->feederclass = fc;
fte->desc = &fc->desc[i];
fte->idx = feedercnt;
fte->desc->idx = feedercnt;
SLIST_INSERT_HEAD(&feedertab, fte, link);
i++;
}
feedercnt++;
if (feedercnt >= MAXFEEDERS)
printf("MAXFEEDERS (%d >= %d) exceeded\n", feedercnt, MAXFEEDERS);
}
static void
feeder_unregisterall(void *p)
{
struct feedertab_entry *fte, *next;
next = SLIST_FIRST(&feedertab);
while (next != NULL) {
fte = next;
next = SLIST_NEXT(fte, link);
free(fte, M_FEEDER);
}
}
static int
cmpdesc(struct pcm_feederdesc *n, struct pcm_feederdesc *m)
{
return ((n->type == m->type) &&
((n->in == 0) || (n->in == m->in)) &&
((n->out == 0) || (n->out == m->out)) &&
(n->flags == m->flags));
}
static void
feeder_destroy(struct pcm_feeder *f)
{
FEEDER_FREE(f);
kobj_delete((kobj_t)f, M_FEEDER);
}
static struct pcm_feeder *
feeder_create(struct feeder_class *fc, struct pcm_feederdesc *desc)
{
struct pcm_feeder *f;
int err;
f = (struct pcm_feeder *)kobj_create((kobj_class_t)fc, M_FEEDER, M_WAITOK | M_ZERO);
if (f == NULL)
return NULL;
f->align = fc->align;
f->data = fc->data;
f->source = NULL;
f->parent = NULL;
f->class = fc;
f->desc = &(f->desc_static);
if (desc) {
*(f->desc) = *desc;
} else {
f->desc->type = FEEDER_ROOT;
f->desc->in = 0;
f->desc->out = 0;
f->desc->flags = 0;
f->desc->idx = 0;
}
err = FEEDER_INIT(f);
if (err) {
printf("feeder_init(%p) on %s returned %d\n", f, fc->name, err);
feeder_destroy(f);
return NULL;
}
return f;
}
struct feeder_class *
feeder_getclass(struct pcm_feederdesc *desc)
{
struct feedertab_entry *fte;
SLIST_FOREACH(fte, &feedertab, link) {
if ((desc == NULL) && (fte->desc == NULL))
return fte->feederclass;
if ((fte->desc != NULL) && (desc != NULL) && cmpdesc(desc, fte->desc))
return fte->feederclass;
}
return NULL;
}
int
chn_addfeeder(struct pcm_channel *c, struct feeder_class *fc, struct pcm_feederdesc *desc)
{
struct pcm_feeder *nf;
nf = feeder_create(fc, desc);
if (nf == NULL)
return ENOSPC;
nf->source = c->feeder;
if (nf->align > 0)
c->align += nf->align;
else if (nf->align < 0 && c->align < -nf->align)
c->align = -nf->align;
c->feeder = nf;
return 0;
}
int
chn_removefeeder(struct pcm_channel *c)
{
struct pcm_feeder *f;
if (c->feeder == NULL)
return -1;
f = c->feeder;
c->feeder = c->feeder->source;
feeder_destroy(f);
return 0;
}
struct pcm_feeder *
chn_findfeeder(struct pcm_channel *c, u_int32_t type)
{
struct pcm_feeder *f;
f = c->feeder;
while (f != NULL) {
if (f->desc->type == type)
return f;
f = f->source;
}
return NULL;
}
static int
chainok(struct pcm_feeder *test, struct pcm_feeder *stop)
{
u_int32_t visited[MAXFEEDERS / 32];
u_int32_t idx, mask;
bzero(visited, sizeof(visited));
while (test && (test != stop)) {
idx = test->desc->idx;
if (idx < 0)
panic("bad idx %d", idx);
if (idx >= MAXFEEDERS)
panic("bad idx %d", idx);
mask = 1 << (idx & 31);
idx >>= 5;
if (visited[idx] & mask)
return 0;
visited[idx] |= mask;
test = test->source;
}
return 1;
}
static struct pcm_feeder *
feeder_fmtchain(u_int32_t *to, struct pcm_feeder *source, struct pcm_feeder *stop, int maxdepth)
{
struct feedertab_entry *fte;
struct pcm_feeder *try, *ret;
/* printf("trying %s (%x -> %x)...\n", source->class->name, source->desc->in, source->desc->out); */
if (fmtvalid(source->desc->out, to)) {
/* printf("got it\n"); */
return source;
}
if (maxdepth < 0)
return NULL;
SLIST_FOREACH(fte, &feedertab, link) {
if (fte->desc == NULL)
continue;
if (fte->desc->type != FEEDER_FMT)
continue;
if (fte->desc->in == source->desc->out) {
try = feeder_create(fte->feederclass, fte->desc);
if (try) {
try->source = source;
ret = chainok(try, stop)? feeder_fmtchain(to, try, stop, maxdepth - 1) : NULL;
if (ret != NULL)
return ret;
feeder_destroy(try);
}
}
}
/* printf("giving up %s...\n", source->class->name); */
return NULL;
}
u_int32_t
chn_fmtchain(struct pcm_channel *c, u_int32_t *to)
{
struct pcm_feeder *try, *del, *stop;
u_int32_t tmpfrom[2], best, *from;
int i, max, bestmax;
KASSERT(c != NULL, ("c == NULL"));
KASSERT(c->feeder != NULL, ("c->feeder == NULL"));
KASSERT(to != NULL, ("to == NULL"));
KASSERT(to[0] != 0, ("to[0] == 0"));
stop = c->feeder;
if (c->direction == PCMDIR_REC && c->feeder->desc->type == FEEDER_ROOT) {
from = chn_getcaps(c)->fmtlist;
} else {
tmpfrom[0] = c->feeder->desc->out;
tmpfrom[1] = 0;
from = tmpfrom;
}
i = 0;
best = 0;
bestmax = 100;
while (from[i] != 0) {
c->feeder->desc->out = from[i];
try = NULL;
max = 0;
while (try == NULL && max < 8) {
try = feeder_fmtchain(to, c->feeder, stop, max);
if (try == NULL)
max++;
}
if (try != NULL && max < bestmax) {
bestmax = max;
best = from[i];
}
while (try != NULL && try != stop) {
del = try;
try = try->source;
feeder_destroy(del);
}
i++;
}
if (best == 0)
return 0;
c->feeder->desc->out = best;
try = feeder_fmtchain(to, c->feeder, stop, bestmax);
if (try == NULL)
return 0;
c->feeder = try;
c->align = 0;
#ifdef FEEDER_DEBUG
printf("\n\nchain: ");
#endif
while (try && (try != stop)) {
#ifdef FEEDER_DEBUG
printf("%s [%d]", try->class->name, try->desc->idx);
if (try->source)
printf(" -> ");
#endif
if (try->source)
try->source->parent = try;
if (try->align > 0)
c->align += try->align;
else if (try->align < 0 && c->align < -try->align)
c->align = -try->align;
try = try->source;
}
#ifdef FEEDER_DEBUG
printf("%s [%d]\n", try->class->name, try->desc->idx);
#endif
return (c->direction == PCMDIR_REC)? best : c->feeder->desc->out;
}
/*****************************************************************************/
static int
feed_root(struct pcm_feeder *feeder, struct pcm_channel *ch, u_int8_t *buffer, u_int32_t count, void *source)
{
struct snd_dbuf *src = source;
int l;
u_int8_t x;
KASSERT(count > 0, ("feed_root: count == 0"));
/* count &= ~((1 << ch->align) - 1); */
KASSERT(count > 0, ("feed_root: aligned count == 0 (align = %d)", ch->align));
l = min(count, sndbuf_getready(src));
sndbuf_dispose(src, buffer, l);
/* When recording only return as much data as available */
if (ch->direction == PCMDIR_REC)
return l;
/*
if (l < count)
printf("appending %d bytes\n", count - l);
*/
x = (sndbuf_getfmt(src) & AFMT_SIGNED)? 0 : 0x80;
while (l < count)
buffer[l++] = x;
return count;
}
static kobj_method_t feeder_root_methods[] = {
KOBJMETHOD(feeder_feed, feed_root),
{ 0, 0 }
};
static struct feeder_class feeder_root_class = {
name: "feeder_root",
methods: feeder_root_methods,
size: sizeof(struct pcm_feeder),
align: 0,
desc: NULL,
data: NULL,
};
SYSINIT(feeder_root, SI_SUB_DRIVERS, SI_ORDER_FIRST, feeder_register, &feeder_root_class);
SYSUNINIT(feeder_root, SI_SUB_DRIVERS, SI_ORDER_FIRST, feeder_unregisterall, NULL);