[RFC PATCH 4/6] ALSA: pcm: Create function for snd_pcm_runtime initialization

Codrin Ciubotariu
2021-05-19T10:50:00Z

Group the setting of snd_pcm_runtime members in a separate function. This
allows for code reutilization. Also, check for substream->ops before
substream->ops->copy_user .

Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
---
include/sound/pcm.h | 2 +
sound/core/pcm_native.c | 108 ++++++++++++++++++++++------------------
2 files changed, 61 insertions(+), 49 deletions(-)

diff --git a/include/sound/pcm.h b/include/sound/pcm.h
index 2907ed2b937f..8e6bd4525c02 100644
--- a/include/sound/pcm.h
+++ b/include/sound/pcm.h
@@ -576,6 +576,8 @@ static inline int snd_pcm_suspend_all(struct snd_pcm *pcm)
int snd_pcm_kernel_ioctl(struct snd_pcm_substream *substream, unsigned int cmd, void *arg);
struct snd_pcm_runtime *snd_pcm_runtime_alloc(void);
void snd_pcm_runtime_free(struct snd_pcm_runtime *runtime);
+void snd_pcm_runtime_set(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params);
int snd_pcm_open_substream(struct snd_pcm *pcm, int stream, struct file *file,
struct snd_pcm_substream **rsubstream);
void snd_pcm_release_substream(struct snd_pcm_substream *substream);
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index cb0164d55593..5b0e7ae2b1e7 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -658,13 +658,69 @@ static int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
return 0;
}

+void snd_pcm_runtime_set(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ unsigned int bits;
+ snd_pcm_uframes_t frames;
+
+ runtime->access = params_access(params);
+ runtime->format = params_format(params);
+ runtime->subformat = params_subformat(params);
+ runtime->channels = params_channels(params);
+ runtime->rate = params_rate(params);
+ runtime->period_size = params_period_size(params);
+ runtime->periods = params_periods(params);
+ runtime->buffer_size = params_buffer_size(params);
+ runtime->info = params->info;
+ runtime->rate_num = params->rate_num;
+ runtime->rate_den = params->rate_den;
+ runtime->no_period_wakeup =
+ (params->info & SNDRV_PCM_INFO_NO_PERIOD_WAKEUP) &&
+ (params->flags & SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP);
+
+ bits = snd_pcm_format_physical_width(runtime->format);
+ runtime->sample_bits = bits;
+ bits *= runtime->channels;
+ runtime->frame_bits = bits;
+ frames = 1;
+ while (bits % 8 != 0) {
+ bits *= 2;
+ frames *= 2;
+ }
+ runtime->byte_align = bits / 8;
+ runtime->min_align = frames;
+
+ /* Default sw params */
+ runtime->tstamp_mode = SNDRV_PCM_TSTAMP_NONE;
+ runtime->period_step = 1;
+ runtime->control->avail_min = runtime->period_size;
+ runtime->start_threshold = 1;
+ runtime->stop_threshold = runtime->buffer_size;
+ runtime->silence_threshold = 0;
+ runtime->silence_size = 0;
+ runtime->boundary = runtime->buffer_size;
+ while (runtime->boundary * 2 <= LONG_MAX - runtime->buffer_size)
+ runtime->boundary *= 2;
+
+ /* clear the buffer for avoiding possible kernel info leaks */
+ if (runtime->dma_area &&
+ !(substream->ops && substream->ops->copy_user)) {
+ size_t size = runtime->dma_bytes;
+
+ if (runtime->info & SNDRV_PCM_INFO_MMAP)
+ size = PAGE_ALIGN(size);
+ memset(runtime->dma_area, 0, size);
+ }
+}
+EXPORT_SYMBOL(snd_pcm_runtime_set);
+
static int snd_pcm_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params)
{
struct snd_pcm_runtime *runtime;
int err, usecs;
- unsigned int bits;
- snd_pcm_uframes_t frames;

if (PCM_RUNTIME_CHECK(substream))
return -ENXIO;
@@ -715,53 +771,7 @@ static int snd_pcm_hw_params(struct snd_pcm_substream *substream,
goto _error;
}

- runtime->access = params_access(params);
- runtime->format = params_format(params);
- runtime->subformat = params_subformat(params);
- runtime->channels = params_channels(params);
- runtime->rate = params_rate(params);
- runtime->period_size = params_period_size(params);
- runtime->periods = params_periods(params);
- runtime->buffer_size = params_buffer_size(params);
- runtime->info = params->info;
- runtime->rate_num = params->rate_num;
- runtime->rate_den = params->rate_den;
- runtime->no_period_wakeup =
- (params->info & SNDRV_PCM_INFO_NO_PERIOD_WAKEUP) &&
- (params->flags & SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP);
-
- bits = snd_pcm_format_physical_width(runtime->format);
- runtime->sample_bits = bits;
- bits *= runtime->channels;
- runtime->frame_bits = bits;
- frames = 1;
- while (bits % 8 != 0) {
- bits *= 2;
- frames *= 2;
- }
- runtime->byte_align = bits / 8;
- runtime->min_align = frames;
-
- /* Default sw params */
- runtime->tstamp_mode = SNDRV_PCM_TSTAMP_NONE;
- runtime->period_step = 1;
- runtime->control->avail_min = runtime->period_size;
- runtime->start_threshold = 1;
- runtime->stop_threshold = runtime->buffer_size;
- runtime->silence_threshold = 0;
- runtime->silence_size = 0;
- runtime->boundary = runtime->buffer_size;
- while (runtime->boundary * 2 <= LONG_MAX - runtime->buffer_size)
- runtime->boundary *= 2;
-
- /* clear the buffer for avoiding possible kernel info leaks */
- if (runtime->dma_area && !substream->ops->copy_user) {
- size_t size = runtime->dma_bytes;
-
- if (runtime->info & SNDRV_PCM_INFO_MMAP)
- size = PAGE_ALIGN(size);
- memset(runtime->dma_area, 0, size);
- }
+ snd_pcm_runtime_set(substream, params);

snd_pcm_timer_resolution_change(substream);
snd_pcm_set_state(substream, SNDRV_PCM_STATE_SETUP);
--
2.27.0