ALSA: compress_offload: Add SNDRV_COMPRESS_AVAIL64 ioctl

The previous patch introduced a 64-bit timestamp ioctl
(SNDRV_COMPRESS_TSTAMP64). To provide a consistent API, this patch
adds a corresponding 64-bit version of the SNDRV_COMPRESS_AVAIL ioctl.

A new struct snd_compr_avail64 is added to the UAPI, which includes
the 64-bit timestamp. The existing ioctl implementation is refactored
to handle both the 32-bit and 64-bit variants.

Reviewed-by: Miller Liang <millerliang@google.com>
Tested-by: Joris Verhaegen <verhaegen@google.com>
Signed-off-by: Joris Verhaegen <verhaegen@google.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20250905091301.2711705-4-verhaegen@google.com

diff --git a/include/uapi/sound/compress_offload.h b/include/uapi/sound/compress_offload.h
index 70b8921601f93196cd797c76cae4117b6949808a..26f756cc2e6215fe99bbac4f4a32ceb475068ec4 100644 (file)
--- a/include/uapi/sound/compress_offload.h
+++ b/include/uapi/sound/compress_offload.h
@@ -84,6 +84,16 @@ struct snd_compr_avail {
        struct snd_compr_tstamp tstamp;
 } __attribute__((packed, aligned(4)));
 
+/**
+ * struct snd_compr_avail64 - avail descriptor with tstamp in 64 bit format
+ * @avail: Number of bytes available in ring buffer for writing/reading
+ * @tstamp: timestamp information
+ */
+struct snd_compr_avail64 {
+       __u64 avail;
+       struct snd_compr_tstamp64 tstamp;
+} __attribute__((packed, aligned(4)));
+
 enum snd_compr_direction {
        SND_COMPRESS_PLAYBACK = 0,
        SND_COMPRESS_CAPTURE,
@@ -231,6 +241,7 @@ struct snd_compr_task_status {
 #define SNDRV_COMPRESS_TSTAMP          _IOR('C', 0x20, struct snd_compr_tstamp)
 #define SNDRV_COMPRESS_AVAIL           _IOR('C', 0x21, struct snd_compr_avail)
 #define SNDRV_COMPRESS_TSTAMP64                _IOR('C', 0x22, struct snd_compr_tstamp64)
+#define SNDRV_COMPRESS_AVAIL64         _IOR('C', 0x23, struct snd_compr_avail64)
 #define SNDRV_COMPRESS_PAUSE           _IO('C', 0x30)
 #define SNDRV_COMPRESS_RESUME          _IO('C', 0x31)
 #define SNDRV_COMPRESS_START           _IO('C', 0x32)

diff --git a/sound/core/compress_offload.c b/sound/core/compress_offload.c
index 445220fdb6a0857601b3687b50b423ced90edc6e..da514fef45bca0164ae811bfdadb56548a463b04 100644 (file)
--- a/sound/core/compress_offload.c
+++ b/sound/core/compress_offload.c
@@ -203,13 +203,10 @@ static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
 }
 
 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
-               struct snd_compr_avail *avail)
+                                  struct snd_compr_avail64 *avail)
 {
-       struct snd_compr_tstamp64 tstamp64 = { 0 };
-
        memset(avail, 0, sizeof(*avail));
-       snd_compr_update_tstamp(stream, &tstamp64);
-       snd_compr_tstamp32_from_64(&avail->tstamp, &tstamp64);
+       snd_compr_update_tstamp(stream, &avail->tstamp);
        /* Still need to return avail even if tstamp can't be filled in */
 
        if (stream->runtime->total_bytes_available == 0 &&
@@ -237,28 +234,43 @@ static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
        if (stream->direction == SND_COMPRESS_PLAYBACK)
                avail->avail = stream->runtime->buffer_size - avail->avail;
 
-       pr_debug("ret avail as %llu\n", avail->avail);
+       pr_debug("ret avail as %zu\n", (size_t)avail->avail);
        return avail->avail;
 }
 
 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
 {
-       struct snd_compr_avail avail;
+       struct snd_compr_avail64 avail;
 
        return snd_compr_calc_avail(stream, &avail);
 }
 
-static int
-snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
+static void snd_compr_avail32_from_64(struct snd_compr_avail *avail32,
+                                     const struct snd_compr_avail64 *avail64)
 {
-       struct snd_compr_avail ioctl_avail;
+       avail32->avail = avail64->avail;
+       snd_compr_tstamp32_from_64(&avail32->tstamp, &avail64->tstamp);
+}
+
+static int snd_compr_ioctl_avail(struct snd_compr_stream *stream,
+                                unsigned long arg, bool is_32bit)
+{
+       struct snd_compr_avail64 ioctl_avail64;
+       struct snd_compr_avail ioctl_avail32;
        size_t avail;
+       const void *copy_from = &ioctl_avail64;
+       size_t copy_size = sizeof(ioctl_avail64);
 
        if (stream->direction == SND_COMPRESS_ACCEL)
                return -EBADFD;
 
-       avail = snd_compr_calc_avail(stream, &ioctl_avail);
-       ioctl_avail.avail = avail;
+       avail = snd_compr_calc_avail(stream, &ioctl_avail64);
+       ioctl_avail64.avail = avail;
+       if (is_32bit) {
+               snd_compr_avail32_from_64(&ioctl_avail32, &ioctl_avail64);
+               copy_from = &ioctl_avail32;
+               copy_size = sizeof(ioctl_avail32);
+       }
 
        switch (stream->runtime->state) {
        case SNDRV_PCM_STATE_OPEN:
@@ -269,8 +281,7 @@ snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
                break;
        }
 
-       if (copy_to_user((__u64 __user *)arg,
-                               &ioctl_avail, sizeof(ioctl_avail)))
+       if (copy_to_user((__u64 __user *)arg, copy_from, copy_size))
                return -EFAULT;
        return 0;
 }
@@ -1336,7 +1347,9 @@ static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
        case SNDRV_COMPRESS_TSTAMP64:
                return snd_compr_tstamp(stream, arg, false);
        case SNDRV_COMPRESS_AVAIL:
-               return snd_compr_ioctl_avail(stream, arg);
+               return snd_compr_ioctl_avail(stream, arg, true);
+       case SNDRV_COMPRESS_AVAIL64:
+               return snd_compr_ioctl_avail(stream, arg, false);
        case SNDRV_COMPRESS_PAUSE:
                return snd_compr_pause(stream);
        case SNDRV_COMPRESS_RESUME: