[ALSA] Fix mmap_count with O_APPEND opened streams

Move mmap_count to snd_pcm_substream instead of runtime struct
so that multiplly opened substreams via O_APPEND can be handled
correctly.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

include/sound/pcm.h

@@ -300,7 +300,6 @@ struct snd_pcm_runtime {
 	/* -- mmap -- */
 	volatile struct snd_pcm_mmap_status *status;
 	volatile struct snd_pcm_mmap_control *control;
-	atomic_t mmap_count;
 
 	/* -- locking / scheduling -- */
 	wait_queue_head_t sleep;
@@ -369,6 +368,7 @@ struct snd_pcm_substream {
 	/* -- assigned files -- */
 	void *file;
 	int ref_count;
+	atomic_t mmap_count;
 	unsigned int f_flags;
 	void (*pcm_release)(struct snd_pcm_substream *);
 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
@@ -972,13 +972,13 @@ struct page *snd_pcm_sgbuf_ops_page(struct snd_pcm_substream *substream, unsigne
 static inline void snd_pcm_mmap_data_open(struct vm_area_struct *area)
 {
 	struct snd_pcm_substream *substream = (struct snd_pcm_substream *)area->vm_private_data;
-	atomic_inc(&substream->runtime->mmap_count);
+	atomic_inc(&substream->mmap_count);
 }
 
 static inline void snd_pcm_mmap_data_close(struct vm_area_struct *area)
 {
 	struct snd_pcm_substream *substream = (struct snd_pcm_substream *)area->vm_private_data;
-	atomic_dec(&substream->runtime->mmap_count);
+	atomic_dec(&substream->mmap_count);
 }
 
 /* mmap for io-memory area */

sound/core/oss/pcm_oss.c

@@ -684,7 +684,7 @@ static int snd_pcm_oss_period_size(struct snd_pcm_substream *substream,
 	oss_buffer_size = snd_pcm_plug_client_size(substream,
 						   snd_pcm_hw_param_value_max(slave_params, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, NULL)) * oss_frame_size;
 	oss_buffer_size = 1 << ld2(oss_buffer_size);
-	if (atomic_read(&runtime->mmap_count)) {
+	if (atomic_read(&substream->mmap_count)) {
 		if (oss_buffer_size > runtime->oss.mmap_bytes)
 			oss_buffer_size = runtime->oss.mmap_bytes;
 	}
@@ -819,7 +819,7 @@ static int snd_pcm_oss_change_params(struct snd_pcm_substream *substream)
 		goto failure;
 	}
 
-	if (atomic_read(&runtime->mmap_count))
+	if (atomic_read(&substream->mmap_count))
 		direct = 1;
 	else
 		direct = substream->oss.setup.direct;
@@ -828,7 +828,7 @@ static int snd_pcm_oss_change_params(struct snd_pcm_substream *substream)
 	_snd_pcm_hw_param_setinteger(sparams, SNDRV_PCM_HW_PARAM_PERIODS);
 	_snd_pcm_hw_param_min(sparams, SNDRV_PCM_HW_PARAM_PERIODS, 2, 0);
 	snd_mask_none(&mask);
-	if (atomic_read(&runtime->mmap_count))
+	if (atomic_read(&substream->mmap_count))
 		snd_mask_set(&mask, SNDRV_PCM_ACCESS_MMAP_INTERLEAVED);
 	else {
 		snd_mask_set(&mask, SNDRV_PCM_ACCESS_RW_INTERLEAVED);
@@ -947,7 +947,8 @@ static int snd_pcm_oss_change_params(struct snd_pcm_substream *substream)
 	} else {
 		sw_params->start_threshold = runtime->boundary;
 	}
-	if (atomic_read(&runtime->mmap_count) || substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+	if (atomic_read(&substream->mmap_count) ||
+	    substream->stream == SNDRV_PCM_STREAM_CAPTURE)
 		sw_params->stop_threshold = runtime->boundary;
 	else
 		sw_params->stop_threshold = runtime->buffer_size;
@@ -957,7 +958,7 @@ static int snd_pcm_oss_change_params(struct snd_pcm_substream *substream)
 	sw_params->avail_min = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ?
 		1 : runtime->period_size;
 	sw_params->xfer_align = 1;
-	if (atomic_read(&runtime->mmap_count) ||
+	if (atomic_read(&substream->mmap_count) ||
 	    substream->oss.setup.nosilence) {
 		sw_params->silence_threshold = 0;
 		sw_params->silence_size = 0;
@@ -1301,7 +1302,7 @@ static ssize_t snd_pcm_oss_write1(struct snd_pcm_substream *substream, const cha
 	ssize_t tmp;
 	struct snd_pcm_runtime *runtime = substream->runtime;
 
-	if (atomic_read(&runtime->mmap_count))
+	if (atomic_read(&substream->mmap_count))
 		return -ENXIO;
 
 	if ((tmp = snd_pcm_oss_make_ready(substream)) < 0)
@@ -1391,7 +1392,7 @@ static ssize_t snd_pcm_oss_read1(struct snd_pcm_substream *substream, char __use
 	ssize_t tmp;
 	struct snd_pcm_runtime *runtime = substream->runtime;
 
-	if (atomic_read(&runtime->mmap_count))
+	if (atomic_read(&substream->mmap_count))
 		return -ENXIO;
 
 	if ((tmp = snd_pcm_oss_make_ready(substream)) < 0)
@@ -1521,7 +1522,7 @@ static int snd_pcm_oss_sync(struct snd_pcm_oss_file *pcm_oss_file)
 	substream = pcm_oss_file->streams[SNDRV_PCM_STREAM_PLAYBACK];
 	if (substream != NULL) {
 		runtime = substream->runtime;
-		if (atomic_read(&runtime->mmap_count))
+		if (atomic_read(&substream->mmap_count))
 			goto __direct;
 		if ((err = snd_pcm_oss_make_ready(substream)) < 0)
 			return err;
@@ -1690,7 +1691,7 @@ static int snd_pcm_oss_get_formats(struct snd_pcm_oss_file *pcm_oss_file)
 
 	if ((err = snd_pcm_oss_get_active_substream(pcm_oss_file, &substream)) < 0)
 		return err;
-	if (atomic_read(&substream->runtime->mmap_count))
+	if (atomic_read(&substream->mmap_count))
 		direct = 1;
 	else
 		direct = substream->oss.setup.direct;
@@ -1900,7 +1901,7 @@ static int snd_pcm_oss_set_trigger(struct snd_pcm_oss_file *pcm_oss_file, int tr
 		if (trigger & PCM_ENABLE_OUTPUT) {
 			if (runtime->oss.trigger)
 				goto _skip1;
-			if (atomic_read(&psubstream->runtime->mmap_count))
+			if (atomic_read(&psubstream->mmap_count))
 				snd_pcm_oss_simulate_fill(psubstream, runtime->hw_ptr_interrupt);
 			runtime->oss.trigger = 1;
 			runtime->start_threshold = 1;
@@ -2018,7 +2019,7 @@ static int snd_pcm_oss_get_ptr(struct snd_pcm_oss_file *pcm_oss_file, int stream
 	if (err < 0)
 		return err;
 	info.ptr = snd_pcm_oss_bytes(substream, runtime->status->hw_ptr % runtime->buffer_size);
-	if (atomic_read(&runtime->mmap_count)) {
+	if (atomic_read(&substream->mmap_count)) {
 		snd_pcm_sframes_t n;
 		n = (delay = runtime->hw_ptr_interrupt) - runtime->oss.prev_hw_ptr_interrupt;
 		if (n < 0)
@@ -2574,7 +2575,7 @@ static ssize_t snd_pcm_oss_write(struct file *file, const char __user *buf, size
 static int snd_pcm_oss_playback_ready(struct snd_pcm_substream *substream)
 {
 	struct snd_pcm_runtime *runtime = substream->runtime;
-	if (atomic_read(&runtime->mmap_count))
+	if (atomic_read(&substream->mmap_count))
 		return runtime->oss.prev_hw_ptr_interrupt != runtime->hw_ptr_interrupt;
 	else
 		return snd_pcm_playback_avail(runtime) >= runtime->oss.period_frames;
@@ -2583,7 +2584,7 @@ static int snd_pcm_oss_playback_ready(struct snd_pcm_substream *substream)
 static int snd_pcm_oss_capture_ready(struct snd_pcm_substream *substream)
 {
 	struct snd_pcm_runtime *runtime = substream->runtime;
-	if (atomic_read(&runtime->mmap_count))
+	if (atomic_read(&substream->mmap_count))
 		return runtime->oss.prev_hw_ptr_interrupt != runtime->hw_ptr_interrupt;
 	else
 		return snd_pcm_capture_avail(runtime) >= runtime->oss.period_frames;

sound/core/pcm.c

@@ -662,6 +662,7 @@ int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
 		INIT_LIST_HEAD(&substream->self_group.substreams);
 		list_add_tail(&substream->link_list, &substream->self_group.substreams);
 		spin_lock_init(&substream->timer_lock);
+		atomic_set(&substream->mmap_count, 0);
 		prev = substream;
 	}
 	return 0;
@@ -884,7 +885,6 @@ int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
 	memset((void*)runtime->control, 0, size);
 
 	init_waitqueue_head(&runtime->sleep);
-	atomic_set(&runtime->mmap_count, 0);
 	init_timer(&runtime->tick_timer);
 	runtime->tick_timer.function = snd_pcm_tick_timer_func;
 	runtime->tick_timer.data = (unsigned long) substream;

sound/core/pcm_native.c

@@ -372,7 +372,7 @@ static int snd_pcm_hw_params(struct snd_pcm_substream *substream,
 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
 	if (!substream->oss.oss)
 #endif
-		if (atomic_read(&runtime->mmap_count))
+		if (atomic_read(&substream->mmap_count))
 			return -EBADFD;
 
 	params->rmask = ~0U;
@@ -485,7 +485,7 @@ static int snd_pcm_hw_free(struct snd_pcm_substream *substream)
 		return -EBADFD;
 	}
 	snd_pcm_stream_unlock_irq(substream);
-	if (atomic_read(&runtime->mmap_count))
+	if (atomic_read(&substream->mmap_count))
 		return -EBADFD;
 	if (substream->ops->hw_free)
 		result = substream->ops->hw_free(substream);
@@ -2207,7 +2207,7 @@ static int snd_pcm_release(struct inode *inode, struct file *file)
 	pcm_file = file->private_data;
 	substream = pcm_file->substream;
 	snd_assert(substream != NULL, return -ENXIO);
-	snd_assert(!atomic_read(&substream->runtime->mmap_count), );
+	snd_assert(!atomic_read(&substream->mmap_count), );
 	pcm = substream->pcm;
 	fasync_helper(-1, file, 0, &substream->runtime->fasync);
 	mutex_lock(&pcm->open_mutex);
@@ -3178,7 +3178,7 @@ static int snd_pcm_default_mmap(struct snd_pcm_substream *substream,
 	area->vm_ops = &snd_pcm_vm_ops_data;
 	area->vm_private_data = substream;
 	area->vm_flags |= VM_RESERVED;
-	atomic_inc(&substream->runtime->mmap_count);
+	atomic_inc(&substream->mmap_count);
 	return 0;
 }
 
@@ -3210,7 +3210,7 @@ int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream,
 				(substream->runtime->dma_addr + offset) >> PAGE_SHIFT,
 				size, area->vm_page_prot))
 		return -EAGAIN;
-	atomic_inc(&substream->runtime->mmap_count);
+	atomic_inc(&substream->mmap_count);
 	return 0;
 }