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.
Signed-off-by: Andy Shevchenko <[email protected]>
---
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
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 <[email protected]>
> ---
> 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
>
On Fri, 21 Jul 2023 12:42:08 +0200,
Andy Shevchenko wrote:
>
> On Fri, Jul 21, 2023 at 12:08:46PM +0200, Takashi Iwai wrote:
> > 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.
>
> Any suggestion for the name?
It's a universal pointer... uniptr_t?
Or a generic pointer, genptr_t?
I'm not good at naming, and I'm open for it.
> And I believe for the bigger series the new callback should be added first.
Yes.
Takashi
On Fri, Jul 21, 2023 at 12:08:46PM +0200, Takashi Iwai wrote:
> 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.
Any suggestion for the name?
And I believe for the bigger series the new callback should be added first.
--
With Best Regards,
Andy Shevchenko
On Fri, Jul 21, 2023 at 12:58:14PM +0200, Takashi Iwai wrote:
> On Fri, 21 Jul 2023 12:42:08 +0200,
> Andy Shevchenko wrote:
> > On Fri, Jul 21, 2023 at 12:08:46PM +0200, Takashi Iwai wrote:
> > > On Fri, 21 Jul 2023 12:01:46 +0200,
> > > Andy Shevchenko wrote:
...
> > > 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.
> > Any suggestion for the name?
>
> It's a universal pointer... uniptr_t?
> Or a generic pointer, genptr_t?
>
> I'm not good at naming, and I'm open for it.
It seems it's already spread enough with this name, I would rather stick with
it for now (besides net it's used in crypto, nvme, and security).
The (new) callback though makes a lot of sense on its own.
What do you think?
--
With Best Regards,
Andy Shevchenko
From: Andy Shevchenko
> Sent: 21 July 2023 11:42
>
> On Fri, Jul 21, 2023 at 12:08:46PM +0200, Takashi Iwai wrote:
> > 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.
>
> Any suggestion for the name?
> And I believe for the bigger series the new callback should be added first.
It would also be better to replace the current sockptr_t with
a structure that contains separate user and kernel addresses
(instead of a union of the pointer types and a flag).
The size of the structure wouldn't change and the code might
even come out better.
There is also scope for adding a length and passing the structure
by reference instead of by value.
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
On Fri, 21 Jul 2023 14:58:05 +0200,
Andy Shevchenko wrote:
>
> On Fri, Jul 21, 2023 at 12:58:14PM +0200, Takashi Iwai wrote:
> > On Fri, 21 Jul 2023 12:42:08 +0200,
> > Andy Shevchenko wrote:
> > > On Fri, Jul 21, 2023 at 12:08:46PM +0200, Takashi Iwai wrote:
> > > > On Fri, 21 Jul 2023 12:01:46 +0200,
> > > > Andy Shevchenko wrote:
>
> ...
>
> > > > 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.
>
> > > Any suggestion for the name?
> >
> > It's a universal pointer... uniptr_t?
> > Or a generic pointer, genptr_t?
> >
> > I'm not good at naming, and I'm open for it.
>
> It seems it's already spread enough with this name, I would rather stick with
> it for now (besides net it's used in crypto, nvme, and security).
>
> The (new) callback though makes a lot of sense on its own.
OK, fair enough.
> What do you think?
Yes, we can go with it.
Basically we need to add a new "copy" callback to take sockptr_t and
use it instead of the old "copy_kernel" and "copy_user" callbacks.
It's used only in sound/core/pcm_lib.c, so it shouldn't be too
difficult, I suppose.
Then replace the defined callbacks in each driver, and finally
deprecate old callbacks.
thanks,
Takashi