ALSA: compress_offload: Add 64-bit safe timestamp infrastructure

The copied_total field in struct snd_compr_tstamp is a 32-bit
value that can overflow on long-running high-bitrate streams,
leading to incorrect calculations for buffer availablility.

This patch adds a 64-bit safe timestamping mechanism.
A new UAPI struct, snd_compr_tstamp64, is added which uses 64-bit
types for byte counters. The relevant ops structures across the
ASoC and core compress code are updated to use this new struct.
ASoC drivers are updated to use u64 counters.

Internal timestamps being u64 now, a compatibility function is added
to convert the 64-bit timestamp back to the 32-bit format for legacy
ioctl callers.

Reviewed-by: Miller Liang <millerliang@google.com>
Tested-by: Joris Verhaegen <verhaegen@google.com>
Signed-off-by: Joris Verhaegen <verhaegen@google.com>
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20250905091301.2711705-2-verhaegen@google.com

5 files changed, 6 insertions, 6 deletions

diff --git a/sound/soc/sof/amd/acp-probes.c b/sound/soc/sof/amd/acp-probes.c
index 0d0f8ec4aed8..ce51ed108a47 100644
--- a/sound/soc/sof/amd/acp-probes.c
+++ b/sound/soc/sof/amd/acp-probes.c
@@ -108,7 +108,7 @@ static int acp_probes_compr_trigger(struct sof_client_dev *cdev,
 
 static int acp_probes_compr_pointer(struct sof_client_dev *cdev,
 				    struct snd_compr_stream *cstream,
-				    struct snd_compr_tstamp *tstamp,
+				    struct snd_compr_tstamp64 *tstamp,
 				    struct snd_soc_dai *dai)
 {
 	struct acp_dsp_stream *stream = cstream->runtime->private_data;
diff --git a/sound/soc/sof/compress.c b/sound/soc/sof/compress.c
index d7b044f33d79..90b932ae3bab 100644
--- a/sound/soc/sof/compress.c
+++ b/sound/soc/sof/compress.c
@@ -361,7 +361,7 @@ static int sof_compr_copy(struct snd_soc_component *component,
 
 static int sof_compr_pointer(struct snd_soc_component *component,
 			     struct snd_compr_stream *cstream,
-			     struct snd_compr_tstamp *tstamp)
+			     struct snd_compr_tstamp64 *tstamp)
 {
 	struct snd_sof_pcm *spcm;
 	struct snd_soc_pcm_runtime *rtd = cstream->private_data;
diff --git a/sound/soc/sof/intel/hda-probes.c b/sound/soc/sof/intel/hda-probes.c
index c645346c2c84..b06933cebc45 100644
--- a/sound/soc/sof/intel/hda-probes.c
+++ b/sound/soc/sof/intel/hda-probes.c
@@ -112,7 +112,7 @@ static int hda_probes_compr_trigger(struct sof_client_dev *cdev,
 
 static int hda_probes_compr_pointer(struct sof_client_dev *cdev,
 				    struct snd_compr_stream *cstream,
-				    struct snd_compr_tstamp *tstamp,
+				    struct snd_compr_tstamp64 *tstamp,
 				    struct snd_soc_dai *dai)
 {
 	struct hdac_ext_stream *hext_stream = hda_compr_get_stream(cstream);
diff --git a/sound/soc/sof/sof-client-probes.c b/sound/soc/sof/sof-client-probes.c
index 663c0d3c314c..1353e911501a 100644
--- a/sound/soc/sof/sof-client-probes.c
+++ b/sound/soc/sof/sof-client-probes.c
@@ -137,7 +137,7 @@ static int sof_probes_compr_trigger(struct snd_compr_stream *cstream, int cmd,
 }
 
 static int sof_probes_compr_pointer(struct snd_compr_stream *cstream,
-				    struct snd_compr_tstamp *tstamp,
+				    struct snd_compr_tstamp64 *tstamp,
 				    struct snd_soc_dai *dai)
 {
 	struct snd_soc_card *card = snd_soc_component_get_drvdata(dai->component);
diff --git a/sound/soc/sof/sof-client-probes.h b/sound/soc/sof/sof-client-probes.h
index da04d65b8d99..8713b69cda4b 100644
--- a/sound/soc/sof/sof-client-probes.h
+++ b/sound/soc/sof/sof-client-probes.h
@@ -4,7 +4,7 @@
 #define __SOF_CLIENT_PROBES_H
 
 struct snd_compr_stream;
-struct snd_compr_tstamp;
+struct snd_compr_tstamp64;
 struct snd_compr_params;
 struct sof_client_dev;
 struct snd_soc_dai;
@@ -24,7 +24,7 @@ struct sof_probes_host_ops {
 	int (*trigger)(struct sof_client_dev *cdev, struct snd_compr_stream *cstream,
 		       int cmd, struct snd_soc_dai *dai);
 	int (*pointer)(struct sof_client_dev *cdev, struct snd_compr_stream *cstream,
-		       struct snd_compr_tstamp *tstamp,
+		       struct snd_compr_tstamp64 *tstamp,
 		       struct snd_soc_dai *dai);
 };