ALSA: pcm: Kill set_fs() in PCM OSS layer

This is the last-standing one: kill the set_fs() usage in PCM OSS
layer by replacing with the new API functions to deal with the direct
in-kernel buffer copying.

The code to fill the silence can be replaced even to a one-liner to
pass NULL buffer instead of the manual copying.

Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/core/oss/pcm_oss.c b/sound/core/oss/pcm_oss.c
index e306f05ce51d12f1dc1a17c90a36a75ccf517d1e..2d6a825cfe88c151382ec6985b3ca5aff5ada417 100644 (file)
--- a/sound/core/oss/pcm_oss.c
+++ b/sound/core/oss/pcm_oss.c
@@ -67,18 +67,6 @@ static int snd_pcm_oss_get_rate(struct snd_pcm_oss_file *pcm_oss_file);
 static int snd_pcm_oss_get_channels(struct snd_pcm_oss_file *pcm_oss_file);
 static int snd_pcm_oss_get_format(struct snd_pcm_oss_file *pcm_oss_file);
 
-static inline mm_segment_t snd_enter_user(void)
-{
-       mm_segment_t fs = get_fs();
-       set_fs(get_ds());
-       return fs;
-}
-
-static inline void snd_leave_user(mm_segment_t fs)
-{
-       set_fs(fs);
-}
-
 /*
  * helper functions to process hw_params
  */
@@ -1191,14 +1179,8 @@ snd_pcm_sframes_t snd_pcm_oss_write3(struct snd_pcm_substream *substream, const
                        if (ret < 0)
                                break;
                }
-               if (in_kernel) {
-                       mm_segment_t fs;
-                       fs = snd_enter_user();
-                       ret = snd_pcm_lib_write(substream, (void __force __user *)ptr, frames);
-                       snd_leave_user(fs);
-               } else {
-                       ret = snd_pcm_lib_write(substream, (void __force __user *)ptr, frames);
-               }
+               ret = __snd_pcm_lib_xfer(substream, (void *)ptr, true,
+                                        frames, in_kernel);
                if (ret != -EPIPE && ret != -ESTRPIPE)
                        break;
                /* test, if we can't store new data, because the stream */
@@ -1234,14 +1216,8 @@ snd_pcm_sframes_t snd_pcm_oss_read3(struct snd_pcm_substream *substream, char *p
                ret = snd_pcm_oss_capture_position_fixup(substream, &delay);
                if (ret < 0)
                        break;
-               if (in_kernel) {
-                       mm_segment_t fs;
-                       fs = snd_enter_user();
-                       ret = snd_pcm_lib_read(substream, (void __force __user *)ptr, frames);
-                       snd_leave_user(fs);
-               } else {
-                       ret = snd_pcm_lib_read(substream, (void __force __user *)ptr, frames);
-               }
+               ret = __snd_pcm_lib_xfer(substream, (void *)ptr, true,
+                                        frames, in_kernel);
                if (ret == -EPIPE) {
                        if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
                                ret = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_DROP, NULL);
@@ -1273,14 +1249,8 @@ snd_pcm_sframes_t snd_pcm_oss_writev3(struct snd_pcm_substream *substream, void
                        if (ret < 0)
                                break;
                }
-               if (in_kernel) {
-                       mm_segment_t fs;
-                       fs = snd_enter_user();
-                       ret = snd_pcm_lib_writev(substream, (void __user **)bufs, frames);
-                       snd_leave_user(fs);
-               } else {
-                       ret = snd_pcm_lib_writev(substream, (void __user **)bufs, frames);
-               }
+               ret = __snd_pcm_lib_xfer(substream, bufs, false, frames,
+                                        in_kernel);
                if (ret != -EPIPE && ret != -ESTRPIPE)
                        break;
 
@@ -1313,14 +1283,8 @@ snd_pcm_sframes_t snd_pcm_oss_readv3(struct snd_pcm_substream *substream, void *
                        if (ret < 0)
                                break;
                }
-               if (in_kernel) {
-                       mm_segment_t fs;
-                       fs = snd_enter_user();
-                       ret = snd_pcm_lib_readv(substream, (void __user **)bufs, frames);
-                       snd_leave_user(fs);
-               } else {
-                       ret = snd_pcm_lib_readv(substream, (void __user **)bufs, frames);
-               }
+               ret = __snd_pcm_lib_xfer(substream, bufs, false, frames,
+                                        in_kernel);
                if (ret != -EPIPE && ret != -ESTRPIPE)
                        break;
        }
@@ -1650,27 +1614,10 @@ static int snd_pcm_oss_sync(struct snd_pcm_oss_file *pcm_oss_file)
                size = runtime->control->appl_ptr % runtime->period_size;
                if (size > 0) {
                        size = runtime->period_size - size;
-                       if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED) {
-                               size = (runtime->frame_bits * size) / 8;
-                               while (size > 0) {
-                                       mm_segment_t fs;
-                                       size_t size1 = size < runtime->oss.period_bytes ? size : runtime->oss.period_bytes;
-                                       size -= size1;
-                                       size1 *= 8;
-                                       size1 /= runtime->sample_bits;
-                                       snd_pcm_format_set_silence(runtime->format,
-                                                                  runtime->oss.buffer,
-                                                                  size1);
-                                       size1 /= runtime->channels; /* frames */
-                                       fs = snd_enter_user();
-                                       snd_pcm_lib_write(substream, (void __force __user *)runtime->oss.buffer, size1);
-                                       snd_leave_user(fs);
-                               }
-                       } else if (runtime->access == SNDRV_PCM_ACCESS_RW_NONINTERLEAVED) {
-                               void __user *buffers[runtime->channels];
-                               memset(buffers, 0, runtime->channels * sizeof(void *));
-                               snd_pcm_lib_writev(substream, buffers, size);
-                       }
+                       if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED)
+                               snd_pcm_lib_write(substream, NULL, size);
+                       else if (runtime->access == SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
+                               snd_pcm_lib_writev(substream, NULL, size);
                }
                mutex_unlock(&runtime->oss.params_lock);
                /*