diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index 4d18941..faedb14 100644
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -1894,6 +1894,7 @@
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	snd_pcm_uframes_t xfer = 0;
 	snd_pcm_uframes_t offset = 0;
+	snd_pcm_uframes_t avail;
 	int err = 0;
 
 	if (size == 0)
@@ -1917,13 +1918,12 @@
 	}
 
 	runtime->twake = runtime->control->avail_min ? : 1;
+	if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
+		snd_pcm_update_hw_ptr(substream);
+	avail = snd_pcm_playback_avail(runtime);
 	while (size > 0) {
 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
-		snd_pcm_uframes_t avail;
 		snd_pcm_uframes_t cont;
-		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
-			snd_pcm_update_hw_ptr(substream);
-		avail = snd_pcm_playback_avail(runtime);
 		if (!avail) {
 			if (nonblock) {
 				err = -EAGAIN;
@@ -1971,6 +1971,7 @@
 		offset += frames;
 		size -= frames;
 		xfer += frames;
+		avail -= frames;
 		if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
 		    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
 			err = snd_pcm_start(substream);
@@ -2111,6 +2112,7 @@
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	snd_pcm_uframes_t xfer = 0;
 	snd_pcm_uframes_t offset = 0;
+	snd_pcm_uframes_t avail;
 	int err = 0;
 
 	if (size == 0)
@@ -2141,13 +2143,12 @@
 	}
 
 	runtime->twake = runtime->control->avail_min ? : 1;
+	if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
+		snd_pcm_update_hw_ptr(substream);
+	avail = snd_pcm_capture_avail(runtime);
 	while (size > 0) {
 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
-		snd_pcm_uframes_t avail;
 		snd_pcm_uframes_t cont;
-		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
-			snd_pcm_update_hw_ptr(substream);
-		avail = snd_pcm_capture_avail(runtime);
 		if (!avail) {
 			if (runtime->status->state ==
 			    SNDRV_PCM_STATE_DRAINING) {
@@ -2202,6 +2203,7 @@
 		offset += frames;
 		size -= frames;
 		xfer += frames;
+		avail -= frames;
 	}
  _end_unlock:
 	runtime->twake = 0;