On Fri, 21 Jul 2023 12:01:46 +0200,
Andy Shevchenko wrote:
>
> The sockptr_t (despite the naming) is a generic type to hold kernel
> or user pointer and there are respective APIs to copy data to or
> from it. Replace open coded variants in the driver by them.
While I see the benefit, I feel this is very confusing. If we use the
API for a generic use, it should be renamed at first.
Also, the current function actually follows the call pattern, and we
know in the caller side whether it's called for a kernel pointer or a
user pointer. So, if any, the PCM core callbacks should be revised to
use a generic pointer instead of fiddling in each driver side.
thanks,
Takashi
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---
> sound/pci/korg1212/korg1212.c | 33 +++++++++++++--------------------
> 1 file changed, 13 insertions(+), 20 deletions(-)
>
> diff --git a/sound/pci/korg1212/korg1212.c b/sound/pci/korg1212/korg1212.c
> index 33b4f95d65b3..92c3eab4d12c 100644
> --- a/sound/pci/korg1212/korg1212.c
> +++ b/sound/pci/korg1212/korg1212.c
> @@ -10,6 +10,7 @@
> #include <linux/interrupt.h>
> #include <linux/pci.h>
> #include <linux/slab.h>
> +#include <linux/sockptr.h>
> #include <linux/wait.h>
> #include <linux/module.h>
> #include <linux/mutex.h>
> @@ -1285,8 +1286,7 @@ static int snd_korg1212_silence(struct snd_korg1212 *korg1212, int pos, int coun
> }
>
> static int snd_korg1212_copy_to(struct snd_pcm_substream *substream,
> - void __user *dst, int pos, int count,
> - bool in_kernel)
> + sockptr_t dst, int pos, int count)
> {
> struct snd_pcm_runtime *runtime = substream->runtime;
> struct snd_korg1212 *korg1212 = snd_pcm_substream_chip(substream);
> @@ -1306,24 +1306,21 @@ static int snd_korg1212_copy_to(struct snd_pcm_substream *substream,
> #if K1212_DEBUG_LEVEL > 0
> if ( (void *) src < (void *) korg1212->recordDataBufsPtr ||
> (void *) src > (void *) korg1212->recordDataBufsPtr[8].bufferData ) {
> - printk(KERN_DEBUG "K1212_DEBUG: snd_korg1212_copy_to KERNEL EFAULT, src=%p dst=%p iter=%d\n", src, dst, i);
> + printk(KERN_DEBUG "K1212_DEBUG: %s KERNEL EFAULT, src=%p dst=%p iter=%d\n",
> + __func__, src, sockptr_is_kernel(dst) ? dst.kernel : dst.user, i);
> return -EFAULT;
> }
> #endif
> - if (in_kernel)
> - memcpy((__force void *)dst, src, size);
> - else if (copy_to_user(dst, src, size))
> + if (copy_to_sockptr_offset(dst, i * size, src, size))
> return -EFAULT;
> src++;
> - dst += size;
> }
>
> return 0;
> }
>
> static int snd_korg1212_copy_from(struct snd_pcm_substream *substream,
> - void __user *src, int pos, int count,
> - bool in_kernel)
> + sockptr_t src, int pos, int count)
> {
> struct snd_pcm_runtime *runtime = substream->runtime;
> struct snd_korg1212 *korg1212 = snd_pcm_substream_chip(substream);
> @@ -1345,16 +1342,14 @@ static int snd_korg1212_copy_from(struct snd_pcm_substream *substream,
> #if K1212_DEBUG_LEVEL > 0
> if ( (void *) dst < (void *) korg1212->playDataBufsPtr ||
> (void *) dst > (void *) korg1212->playDataBufsPtr[8].bufferData ) {
> - printk(KERN_DEBUG "K1212_DEBUG: snd_korg1212_copy_from KERNEL EFAULT, src=%p dst=%p iter=%d\n", src, dst, i);
> + printk(KERN_DEBUG "K1212_DEBUG: %s KERNEL EFAULT, src=%p dst=%p iter=%d\n",
> + __func__, sockptr_is_kernel(src) ? src.kernel : src.user, dst, i);
> return -EFAULT;
> }
> #endif
> - if (in_kernel)
> - memcpy(dst, (__force void *)src, size);
> - else if (copy_from_user(dst, src, size))
> + if (copy_from_sockptr_offset(dst, src, i * size, size))
> return -EFAULT;
> dst++;
> - src += size;
> }
>
> return 0;
> @@ -1644,15 +1639,14 @@ static int snd_korg1212_playback_copy(struct snd_pcm_substream *substream,
> int channel, unsigned long pos,
> void __user *src, unsigned long count)
> {
> - return snd_korg1212_copy_from(substream, src, pos, count, false);
> + return snd_korg1212_copy_from(substream, USER_SOCKPTR(src), pos, count);
> }
>
> static int snd_korg1212_playback_copy_kernel(struct snd_pcm_substream *substream,
> int channel, unsigned long pos,
> void *src, unsigned long count)
> {
> - return snd_korg1212_copy_from(substream, (void __user *)src,
> - pos, count, true);
> + return snd_korg1212_copy_from(substream, KERNEL_SOCKPTR(src), pos, count);
> }
>
> static int snd_korg1212_playback_silence(struct snd_pcm_substream *substream,
> @@ -1672,15 +1666,14 @@ static int snd_korg1212_capture_copy(struct snd_pcm_substream *substream,
> int channel, unsigned long pos,
> void __user *dst, unsigned long count)
> {
> - return snd_korg1212_copy_to(substream, dst, pos, count, false);
> + return snd_korg1212_copy_to(substream, USER_SOCKPTR(dst), pos, count);
> }
>
> static int snd_korg1212_capture_copy_kernel(struct snd_pcm_substream *substream,
> int channel, unsigned long pos,
> void *dst, unsigned long count)
> {
> - return snd_korg1212_copy_to(substream, (void __user *)dst,
> - pos, count, true);
> + return snd_korg1212_copy_to(substream, KERNEL_SOCKPTR(dst), pos, count);
> }
>
> static const struct snd_pcm_ops snd_korg1212_playback_ops = {
> --
> 2.40.0.1.gaa8946217a0b
>
