Re: [PATCH v2 1/6] iommu/ipmmu-vmsa: Link IOMMUs and devices in sysfs

2019-04-23 Thread Geert Uytterhoeven 
Hi Simon,

On Thu, Apr 11, 2019 at 10:12 AM Simon Horman  wrote:
> On Thu, Apr 11, 2019 at 10:10:28AM +0200, Simon Horman wrote:
> > On Wed, Apr 03, 2019 at 08:21:43PM +0200, Geert Uytterhoeven wrote:
> > > As of commit 7af9a5fdb9e0ca33 ("iommu/ipmmu-vmsa: Use
> > > iommu_device_sysfs_add()/remove()"), IOMMU devices show up under
> > > /sys/class/iommus/, but their "devices" subdirectories are empty.
> >
> > Should the path be /sys/class/iommu/ (no trailing 's') ?

Yes it does, thanks. Will fix.

> > > Likewise, devices tied to an IOMMU do not have an "iommu" backlink.
> > >
> > > Make sure all links are created, on both arm32 and arm64.
> > >
> > > Signed-off-by: Geert Uytterhoeven 
> > > Reviewed-by: Laurent Pinchart 
> > > ---
> > > v2:
> > >   - Add Reviewed-by.
> > > ---
> > >  drivers/iommu/ipmmu-vmsa.c | 24 +---
> > >  1 file changed, 17 insertions(+), 7 deletions(-)
> > >
> > > diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
> > > index 9a380c10655e182d..9f2b781e20a0eba6 100644
> > > --- a/drivers/iommu/ipmmu-vmsa.c
> > > +++ b/drivers/iommu/ipmmu-vmsa.c
> > > @@ -885,27 +885,37 @@ static int ipmmu_init_arm_mapping(struct device 
> > > *dev)
> > >
> > >  static int ipmmu_add_device(struct device *dev)
> > >  {
> > > +   struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
> > > struct iommu_group *group;
> > > +   int ret;
> > >
> > > /*
> > >  * Only let through devices that have been verified in xlate()
> > >  */
> > > -   if (!to_ipmmu(dev))
> > > +   if (!mmu)
> > > return -ENODEV;
> > >
> > > -   if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA))
> > > -   return ipmmu_init_arm_mapping(dev);
> > > +   if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA)) {
> > > +   ret = ipmmu_init_arm_mapping(dev);
> > > +   if (ret)
> > > +   return ret;
> > > +   } else {
> > > +   group = iommu_group_get_for_dev(dev);
> > > +   if (IS_ERR(group))
> > > +   return PTR_ERR(group);
> > >
> > > -   group = iommu_group_get_for_dev(dev);
> > > -   if (IS_ERR(group))
> > > -   return PTR_ERR(group);
> > > +   iommu_group_put(group);
> > > +   }
> > >
> > > -   iommu_group_put(group);
> > > +   iommu_device_link(>iommu, dev);
>
> Also, is there any value in propagating the return value
> of iommu_device_link() ?

I don't think so.  Sysfs information is not super-critical, and most
drivers just
ignore such return values.  Also, the sysfs cleanup code handles cleanup
after failed setup fine.

Gr{oetje,eeting}s,

Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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Re: [PATCH v2 1/6] iommu/ipmmu-vmsa: Link IOMMUs and devices in sysfs

2019-04-11 Thread Simon Horman 
On Wed, Apr 03, 2019 at 08:21:43PM +0200, Geert Uytterhoeven wrote:
> As of commit 7af9a5fdb9e0ca33 ("iommu/ipmmu-vmsa: Use
> iommu_device_sysfs_add()/remove()"), IOMMU devices show up under
> /sys/class/iommus/, but their "devices" subdirectories are empty.

Hi Geert,

Should the path be /sys/class/iommu/ (no trailing 's') ?

> Likewise, devices tied to an IOMMU do not have an "iommu" backlink.
> 
> Make sure all links are created, on both arm32 and arm64.
> 
> Signed-off-by: Geert Uytterhoeven 
> Reviewed-by: Laurent Pinchart 
> ---
> v2:
>   - Add Reviewed-by.
> ---
>  drivers/iommu/ipmmu-vmsa.c | 24 +---
>  1 file changed, 17 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
> index 9a380c10655e182d..9f2b781e20a0eba6 100644
> --- a/drivers/iommu/ipmmu-vmsa.c
> +++ b/drivers/iommu/ipmmu-vmsa.c
> @@ -885,27 +885,37 @@ static int ipmmu_init_arm_mapping(struct device *dev)
>  
>  static int ipmmu_add_device(struct device *dev)
>  {
> + struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
>   struct iommu_group *group;
> + int ret;
>  
>   /*
>* Only let through devices that have been verified in xlate()
>*/
> - if (!to_ipmmu(dev))
> + if (!mmu)
>   return -ENODEV;
>  
> - if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA))
> - return ipmmu_init_arm_mapping(dev);
> + if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA)) {
> + ret = ipmmu_init_arm_mapping(dev);
> + if (ret)
> + return ret;
> + } else {
> + group = iommu_group_get_for_dev(dev);
> + if (IS_ERR(group))
> + return PTR_ERR(group);
>  
> - group = iommu_group_get_for_dev(dev);
> - if (IS_ERR(group))
> - return PTR_ERR(group);
> + iommu_group_put(group);
> + }
>  
> - iommu_group_put(group);
> + iommu_device_link(>iommu, dev);
>   return 0;
>  }
>  
>  static void ipmmu_remove_device(struct device *dev)
>  {
> + struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
> +
> + iommu_device_unlink(>iommu, dev);
>   arm_iommu_detach_device(dev);
>   iommu_group_remove_device(dev);
>  }
> -- 
> 2.17.1
> 
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Re: [PATCH v2 1/6] iommu/ipmmu-vmsa: Link IOMMUs and devices in sysfs

2019-04-11 Thread Simon Horman 
On Thu, Apr 11, 2019 at 10:10:28AM +0200, Simon Horman wrote:
> On Wed, Apr 03, 2019 at 08:21:43PM +0200, Geert Uytterhoeven wrote:
> > As of commit 7af9a5fdb9e0ca33 ("iommu/ipmmu-vmsa: Use
> > iommu_device_sysfs_add()/remove()"), IOMMU devices show up under
> > /sys/class/iommus/, but their "devices" subdirectories are empty.
> 
> Hi Geert,
> 
> Should the path be /sys/class/iommu/ (no trailing 's') ?
> 
> > Likewise, devices tied to an IOMMU do not have an "iommu" backlink.
> > 
> > Make sure all links are created, on both arm32 and arm64.
> > 
> > Signed-off-by: Geert Uytterhoeven 
> > Reviewed-by: Laurent Pinchart 
> > ---
> > v2:
> >   - Add Reviewed-by.
> > ---
> >  drivers/iommu/ipmmu-vmsa.c | 24 +---
> >  1 file changed, 17 insertions(+), 7 deletions(-)
> > 
> > diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
> > index 9a380c10655e182d..9f2b781e20a0eba6 100644
> > --- a/drivers/iommu/ipmmu-vmsa.c
> > +++ b/drivers/iommu/ipmmu-vmsa.c
> > @@ -885,27 +885,37 @@ static int ipmmu_init_arm_mapping(struct device *dev)
> >  
> >  static int ipmmu_add_device(struct device *dev)
> >  {
> > +   struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
> > struct iommu_group *group;
> > +   int ret;
> >  
> > /*
> >  * Only let through devices that have been verified in xlate()
> >  */
> > -   if (!to_ipmmu(dev))
> > +   if (!mmu)
> > return -ENODEV;
> >  
> > -   if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA))
> > -   return ipmmu_init_arm_mapping(dev);
> > +   if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA)) {
> > +   ret = ipmmu_init_arm_mapping(dev);
> > +   if (ret)
> > +   return ret;
> > +   } else {
> > +   group = iommu_group_get_for_dev(dev);
> > +   if (IS_ERR(group))
> > +   return PTR_ERR(group);
> >  
> > -   group = iommu_group_get_for_dev(dev);
> > -   if (IS_ERR(group))
> > -   return PTR_ERR(group);
> > +   iommu_group_put(group);
> > +   }
> >  
> > -   iommu_group_put(group);
> > +   iommu_device_link(>iommu, dev);

Also, is there any value in propagating the return value
of iommu_device_link() ?

> > return 0;
> >  }
> >  
> >  static void ipmmu_remove_device(struct device *dev)
> >  {
> > +   struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
> > +
> > +   iommu_device_unlink(>iommu, dev);
> > arm_iommu_detach_device(dev);
> > iommu_group_remove_device(dev);
> >  }
> > -- 
> > 2.17.1
> > 
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[PATCH v2 1/6] iommu/ipmmu-vmsa: Link IOMMUs and devices in sysfs

2019-04-03 Thread Geert Uytterhoeven 
As of commit 7af9a5fdb9e0ca33 ("iommu/ipmmu-vmsa: Use
iommu_device_sysfs_add()/remove()"), IOMMU devices show up under
/sys/class/iommus/, but their "devices" subdirectories are empty.
Likewise, devices tied to an IOMMU do not have an "iommu" backlink.

Make sure all links are created, on both arm32 and arm64.

Signed-off-by: Geert Uytterhoeven 
Reviewed-by: Laurent Pinchart 
---
v2:
  - Add Reviewed-by.
---
 drivers/iommu/ipmmu-vmsa.c | 24 +---
 1 file changed, 17 insertions(+), 7 deletions(-)

diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
index 9a380c10655e182d..9f2b781e20a0eba6 100644
--- a/drivers/iommu/ipmmu-vmsa.c
+++ b/drivers/iommu/ipmmu-vmsa.c
@@ -885,27 +885,37 @@ static int ipmmu_init_arm_mapping(struct device *dev)
 
 static int ipmmu_add_device(struct device *dev)
 {
+   struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
struct iommu_group *group;
+   int ret;
 
/*
 * Only let through devices that have been verified in xlate()
 */
-   if (!to_ipmmu(dev))
+   if (!mmu)
return -ENODEV;
 
-   if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA))
-   return ipmmu_init_arm_mapping(dev);
+   if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA)) {
+   ret = ipmmu_init_arm_mapping(dev);
+   if (ret)
+   return ret;
+   } else {
+   group = iommu_group_get_for_dev(dev);
+   if (IS_ERR(group))
+   return PTR_ERR(group);
 
-   group = iommu_group_get_for_dev(dev);
-   if (IS_ERR(group))
-   return PTR_ERR(group);
+   iommu_group_put(group);
+   }
 
-   iommu_group_put(group);
+   iommu_device_link(>iommu, dev);
return 0;
 }
 
 static void ipmmu_remove_device(struct device *dev)
 {
+   struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
+
+   iommu_device_unlink(>iommu, dev);
arm_iommu_detach_device(dev);
iommu_group_remove_device(dev);
 }
-- 
2.17.1

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