[ALSA] Add O_APPEND flag support to PCM
Added O_APPEND flag support to PCM to enable shared substreams
among multiple processes. This mechanism is used by dmix and
dsnoop plugins.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/include/sound/asound.h b/include/sound/asound.h
index 9cc021c..41885f4 100644
--- a/include/sound/asound.h
+++ b/include/sound/asound.h
@@ -137,7 +137,7 @@
* *
*****************************************************************************/
-#define SNDRV_PCM_VERSION SNDRV_PROTOCOL_VERSION(2, 0, 7)
+#define SNDRV_PCM_VERSION SNDRV_PROTOCOL_VERSION(2, 0, 8)
typedef unsigned long snd_pcm_uframes_t;
typedef signed long snd_pcm_sframes_t;
diff --git a/include/sound/pcm.h b/include/sound/pcm.h
index 998bace..cebf031 100644
--- a/include/sound/pcm.h
+++ b/include/sound/pcm.h
@@ -368,7 +368,8 @@
struct snd_pcm_group *group; /* pointer to current group */
/* -- assigned files -- */
void *file;
- struct file *ffile;
+ int ref_count;
+ unsigned int f_flags;
void (*pcm_release)(struct snd_pcm_substream *);
#if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
/* -- OSS things -- */
@@ -387,7 +388,7 @@
unsigned int hw_opened: 1;
};
-#define SUBSTREAM_BUSY(substream) ((substream)->file != NULL)
+#define SUBSTREAM_BUSY(substream) ((substream)->ref_count > 0)
struct snd_pcm_str {
diff --git a/sound/core/oss/pcm_oss.c b/sound/core/oss/pcm_oss.c
index d8b7416..9803a6c 100644
--- a/sound/core/oss/pcm_oss.c
+++ b/sound/core/oss/pcm_oss.c
@@ -1331,7 +1331,7 @@
if (runtime->oss.period_ptr == 0 ||
runtime->oss.period_ptr == runtime->oss.buffer_used)
runtime->oss.buffer_used = 0;
- else if ((substream->ffile->f_flags & O_NONBLOCK) != 0)
+ else if ((substream->f_flags & O_NONBLOCK) != 0)
return xfer > 0 ? xfer : -EAGAIN;
}
} else {
@@ -1344,7 +1344,7 @@
buf += tmp;
bytes -= tmp;
xfer += tmp;
- if ((substream->ffile->f_flags & O_NONBLOCK) != 0 &&
+ if ((substream->f_flags & O_NONBLOCK) != 0 &&
tmp != runtime->oss.period_bytes)
break;
}
@@ -1582,10 +1582,10 @@
* finish sync: drain the buffer
*/
__direct:
- saved_f_flags = substream->ffile->f_flags;
- substream->ffile->f_flags &= ~O_NONBLOCK;
+ saved_f_flags = substream->f_flags;
+ substream->f_flags &= ~O_NONBLOCK;
err = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_DRAIN, NULL);
- substream->ffile->f_flags = saved_f_flags;
+ substream->f_flags = saved_f_flags;
if (err < 0)
return err;
runtime->oss.prepare = 1;
@@ -2164,9 +2164,9 @@
substream->oss.oss = 1;
substream->oss.setup = *setup;
if (setup->nonblock)
- substream->ffile->f_flags |= O_NONBLOCK;
+ substream->f_flags |= O_NONBLOCK;
else if (setup->block)
- substream->ffile->f_flags &= ~O_NONBLOCK;
+ substream->f_flags &= ~O_NONBLOCK;
runtime = substream->runtime;
runtime->oss.params = 1;
runtime->oss.trigger = 1;
@@ -2223,6 +2223,7 @@
(pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX))
f_mode = FMODE_WRITE;
+ file->f_flags &= ~O_APPEND;
for (idx = 0; idx < 2; idx++) {
if (setup[idx].disable)
continue;
@@ -2540,6 +2541,7 @@
substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_CAPTURE];
if (substream == NULL)
return -ENXIO;
+ substream->f_flags = file->f_flags & O_NONBLOCK;
#ifndef OSS_DEBUG
return snd_pcm_oss_read1(substream, buf, count);
#else
@@ -2561,6 +2563,7 @@
substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK];
if (substream == NULL)
return -ENXIO;
+ substream->f_flags = file->f_flags & O_NONBLOCK;
result = snd_pcm_oss_write1(substream, buf, count);
#ifdef OSS_DEBUG
printk("pcm_oss: write %li bytes (wrote %li bytes)\n", (long)count, (long)result);
diff --git a/sound/core/pcm.c b/sound/core/pcm.c
index 4f52041..8136be2 100644
--- a/sound/core/pcm.c
+++ b/sound/core/pcm.c
@@ -829,6 +829,26 @@
return -EINVAL;
}
+ if (file->f_flags & O_APPEND) {
+ if (prefer_subdevice < 0) {
+ if (pstr->substream_count > 1)
+ return -EINVAL; /* must be unique */
+ substream = pstr->substream;
+ } else {
+ for (substream = pstr->substream; substream;
+ substream = substream->next)
+ if (substream->number == prefer_subdevice)
+ break;
+ }
+ if (! substream)
+ return -ENODEV;
+ if (! SUBSTREAM_BUSY(substream))
+ return -EBADFD;
+ substream->ref_count++;
+ *rsubstream = substream;
+ return 0;
+ }
+
if (prefer_subdevice >= 0) {
for (substream = pstr->substream; substream; substream = substream->next)
if (!SUBSTREAM_BUSY(substream) && substream->number == prefer_subdevice)
@@ -873,7 +893,8 @@
substream->runtime = runtime;
substream->private_data = pcm->private_data;
- substream->ffile = file;
+ substream->ref_count = 1;
+ substream->f_flags = file->f_flags;
pstr->substream_opened++;
*rsubstream = substream;
return 0;
@@ -882,7 +903,7 @@
void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime;
- substream->file = NULL;
+
runtime = substream->runtime;
snd_assert(runtime != NULL, return);
if (runtime->private_free != NULL)
diff --git a/sound/core/pcm_compat.c b/sound/core/pcm_compat.c
index e513303..2b8aab6 100644
--- a/sound/core/pcm_compat.c
+++ b/sound/core/pcm_compat.c
@@ -497,9 +497,9 @@
case SNDRV_PCM_IOCTL_LINK:
case SNDRV_PCM_IOCTL_UNLINK:
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
- return snd_pcm_playback_ioctl1(substream, cmd, argp);
+ return snd_pcm_playback_ioctl1(file, substream, cmd, argp);
else
- return snd_pcm_capture_ioctl1(substream, cmd, argp);
+ return snd_pcm_capture_ioctl1(file, substream, cmd, argp);
case SNDRV_PCM_IOCTL_HW_REFINE32:
return snd_pcm_ioctl_hw_params_compat(substream, 1, argp);
case SNDRV_PCM_IOCTL_HW_PARAMS32:
diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index a21aa00..0bb142a 100644
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -1782,7 +1782,7 @@
if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
return -EBADFD;
- nonblock = !!(substream->ffile->f_flags & O_NONBLOCK);
+ nonblock = !!(substream->f_flags & O_NONBLOCK);
if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
runtime->channels > 1)
@@ -1847,7 +1847,7 @@
if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
return -EBADFD;
- nonblock = !!(substream->ffile->f_flags & O_NONBLOCK);
+ nonblock = !!(substream->f_flags & O_NONBLOCK);
if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
return -EINVAL;
@@ -2059,7 +2059,7 @@
if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
return -EBADFD;
- nonblock = !!(substream->ffile->f_flags & O_NONBLOCK);
+ nonblock = !!(substream->f_flags & O_NONBLOCK);
if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
return -EINVAL;
return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
@@ -2118,7 +2118,7 @@
if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
return -EBADFD;
- nonblock = !!(substream->ffile->f_flags & O_NONBLOCK);
+ nonblock = !!(substream->f_flags & O_NONBLOCK);
if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
return -EINVAL;
return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 7b5729c..36d6765 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -1284,13 +1284,16 @@
/*
* prepare ioctl
*/
-static int snd_pcm_pre_prepare(struct snd_pcm_substream *substream, int state)
+/* we use the second argument for updating f_flags */
+static int snd_pcm_pre_prepare(struct snd_pcm_substream *substream,
+ int f_flags)
{
struct snd_pcm_runtime *runtime = substream->runtime;
if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
return -EBADFD;
if (snd_pcm_running(substream))
return -EBUSY;
+ substream->f_flags = f_flags;
return 0;
}
@@ -1319,17 +1322,26 @@
/**
* snd_pcm_prepare
* @substream: the PCM substream instance
+ * @file: file to refer f_flags
*
* Prepare the PCM substream to be triggerable.
*/
-static int snd_pcm_prepare(struct snd_pcm_substream *substream)
+static int snd_pcm_prepare(struct snd_pcm_substream *substream,
+ struct file *file)
{
int res;
struct snd_card *card = substream->pcm->card;
+ int f_flags;
+
+ if (file)
+ f_flags = file->f_flags;
+ else
+ f_flags = substream->f_flags;
snd_power_lock(card);
if ((res = snd_power_wait(card, SNDRV_CTL_POWER_D0)) >= 0)
- res = snd_pcm_action_nonatomic(&snd_pcm_action_prepare, substream, 0);
+ res = snd_pcm_action_nonatomic(&snd_pcm_action_prepare,
+ substream, f_flags);
snd_power_unlock(card);
return res;
}
@@ -1340,7 +1352,7 @@
static int snd_pcm_pre_drain_init(struct snd_pcm_substream *substream, int state)
{
- if (substream->ffile->f_flags & O_NONBLOCK)
+ if (substream->f_flags & O_NONBLOCK)
return -EAGAIN;
substream->runtime->trigger_master = substream;
return 0;
@@ -2015,6 +2027,10 @@
void snd_pcm_release_substream(struct snd_pcm_substream *substream)
{
+ substream->ref_count--;
+ if (substream->ref_count > 0)
+ return;
+
snd_pcm_drop(substream);
if (substream->hw_opened) {
if (substream->ops->hw_free != NULL)
@@ -2041,6 +2057,11 @@
err = snd_pcm_attach_substream(pcm, stream, file, &substream);
if (err < 0)
return err;
+ if (substream->ref_count > 1) {
+ *rsubstream = substream;
+ return 0;
+ }
+
substream->no_mmap_ctrl = 0;
err = snd_pcm_hw_constraints_init(substream);
if (err < 0) {
@@ -2086,17 +2107,20 @@
if (err < 0)
return err;
- pcm_file = kzalloc(sizeof(*pcm_file), GFP_KERNEL);
- if (pcm_file == NULL) {
- snd_pcm_release_substream(substream);
- return -ENOMEM;
+ if (substream->ref_count > 1)
+ pcm_file = substream->file;
+ else {
+ pcm_file = kzalloc(sizeof(*pcm_file), GFP_KERNEL);
+ if (pcm_file == NULL) {
+ snd_pcm_release_substream(substream);
+ return -ENOMEM;
+ }
+ str = substream->pstr;
+ substream->file = pcm_file;
+ substream->pcm_release = pcm_release_private;
+ pcm_file->substream = substream;
+ snd_pcm_add_file(str, pcm_file);
}
- str = substream->pstr;
- substream->file = pcm_file;
- substream->pcm_release = pcm_release_private;
- pcm_file->substream = substream;
- snd_pcm_add_file(str, pcm_file);
-
file->private_data = pcm_file;
*rpcm_file = pcm_file;
return 0;
@@ -2506,7 +2530,8 @@
return 0;
}
-static int snd_pcm_common_ioctl1(struct snd_pcm_substream *substream,
+static int snd_pcm_common_ioctl1(struct file *file,
+ struct snd_pcm_substream *substream,
unsigned int cmd, void __user *arg)
{
snd_assert(substream != NULL, return -ENXIO);
@@ -2531,7 +2556,7 @@
case SNDRV_PCM_IOCTL_CHANNEL_INFO:
return snd_pcm_channel_info_user(substream, arg);
case SNDRV_PCM_IOCTL_PREPARE:
- return snd_pcm_prepare(substream);
+ return snd_pcm_prepare(substream, file);
case SNDRV_PCM_IOCTL_RESET:
return snd_pcm_reset(substream);
case SNDRV_PCM_IOCTL_START:
@@ -2573,7 +2598,8 @@
return -ENOTTY;
}
-static int snd_pcm_playback_ioctl1(struct snd_pcm_substream *substream,
+static int snd_pcm_playback_ioctl1(struct file *file,
+ struct snd_pcm_substream *substream,
unsigned int cmd, void __user *arg)
{
snd_assert(substream != NULL, return -ENXIO);
@@ -2649,10 +2675,11 @@
return result < 0 ? result : 0;
}
}
- return snd_pcm_common_ioctl1(substream, cmd, arg);
+ return snd_pcm_common_ioctl1(file, substream, cmd, arg);
}
-static int snd_pcm_capture_ioctl1(struct snd_pcm_substream *substream,
+static int snd_pcm_capture_ioctl1(struct file *file,
+ struct snd_pcm_substream *substream,
unsigned int cmd, void __user *arg)
{
snd_assert(substream != NULL, return -ENXIO);
@@ -2728,7 +2755,7 @@
return result < 0 ? result : 0;
}
}
- return snd_pcm_common_ioctl1(substream, cmd, arg);
+ return snd_pcm_common_ioctl1(file, substream, cmd, arg);
}
static long snd_pcm_playback_ioctl(struct file *file, unsigned int cmd,
@@ -2741,7 +2768,8 @@
if (((cmd >> 8) & 0xff) != 'A')
return -ENOTTY;
- return snd_pcm_playback_ioctl1(pcm_file->substream, cmd, (void __user *)arg);
+ return snd_pcm_playback_ioctl1(file, pcm_file->substream, cmd,
+ (void __user *)arg);
}
static long snd_pcm_capture_ioctl(struct file *file, unsigned int cmd,
@@ -2754,7 +2782,8 @@
if (((cmd >> 8) & 0xff) != 'A')
return -ENOTTY;
- return snd_pcm_capture_ioctl1(pcm_file->substream, cmd, (void __user *)arg);
+ return snd_pcm_capture_ioctl1(file, pcm_file->substream, cmd,
+ (void __user *)arg);
}
int snd_pcm_kernel_ioctl(struct snd_pcm_substream *substream,
@@ -2766,12 +2795,12 @@
fs = snd_enter_user();
switch (substream->stream) {
case SNDRV_PCM_STREAM_PLAYBACK:
- result = snd_pcm_playback_ioctl1(substream,
- cmd, (void __user *)arg);
+ result = snd_pcm_playback_ioctl1(NULL, substream, cmd,
+ (void __user *)arg);
break;
case SNDRV_PCM_STREAM_CAPTURE:
- result = snd_pcm_capture_ioctl1(substream,
- cmd, (void __user *)arg);
+ result = snd_pcm_capture_ioctl1(NULL, substream, cmd,
+ (void __user *)arg);
break;
default:
result = -EINVAL;
diff --git a/sound/usb/usx2y/usx2yhwdeppcm.c b/sound/usb/usx2y/usx2yhwdeppcm.c
index fe67a92..88b72b5 100644
--- a/sound/usb/usx2y/usx2yhwdeppcm.c
+++ b/sound/usb/usx2y/usx2yhwdeppcm.c
@@ -632,7 +632,7 @@
for (s = 0; s < 2; ++s) {
struct snd_pcm_substream *substream;
substream = pcm->streams[s].substream;
- if (substream && substream->ffile != NULL)
+ if (SUBSTREAM_BUSY(substream))
err = -EBUSY;
}
}