[PATCH 1/3] iommu: Return ERR_PTR() values from device_group call-backs

[PATCH 1/3] iommu: Return ERR_PTR() values from device_group call-backs

[Joerg Roedel]

From: Joerg Roedel <jroedel@suse.de>

The generic device_group call-backs in iommu.c return NULL
in case of error. Since they are getting ERR_PTR values from
iommu_group_alloc(), just pass them up instead.

Reported-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
 drivers/iommu/iommu.c | 14 ++------------
 1 file changed, 2 insertions(+), 12 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index cf7ca7e..de09e1e 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -915,13 +915,7 @@ static int get_pci_alias_or_group(struct pci_dev *pdev, u16 alias, void *opaque)
  */
 struct iommu_group *generic_device_group(struct device *dev)
 {
-	struct iommu_group *group;
-
-	group = iommu_group_alloc();
-	if (IS_ERR(group))
-		return NULL;
-
-	return group;
+	return iommu_group_alloc();
 }
 
 /*
@@ -988,11 +982,7 @@ struct iommu_group *pci_device_group(struct device *dev)
 		return group;
 
 	/* No shared group found, allocate new */
-	group = iommu_group_alloc();
-	if (IS_ERR(group))
-		return NULL;
-
-	return group;
+	return iommu_group_alloc();
 }
 
 /**
-- 
2.7.4

[PATCH 2/3] iommu/omap: Return ERR_PTR in device_group call-back

[Joerg Roedel]

From: Joerg Roedel <jroedel@suse.de>

Make sure that the device_group callback returns an ERR_PTR
instead of NULL.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
 drivers/iommu/omap-iommu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
index 95dfca3..641e035 100644
--- a/drivers/iommu/omap-iommu.c
+++ b/drivers/iommu/omap-iommu.c
@@ -1309,7 +1309,7 @@ static void omap_iommu_remove_device(struct device *dev)
 static struct iommu_group *omap_iommu_device_group(struct device *dev)
 {
 	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
-	struct iommu_group *group = NULL;
+	struct iommu_group *group = ERR_PTR(-EINVAL);
 
 	if (arch_data->iommu_dev)
 		group = arch_data->iommu_dev->group;
-- 
2.7.4

Re: [PATCH 2/3] iommu/omap: Return ERR_PTR in device_group call-back

[Suman Anna]

On 06/28/2017 07:00 AM, Joerg Roedel wrote:
> From: Joerg Roedel <jroedel@suse.de>
> 
> Make sure that the device_group callback returns an ERR_PTR
> instead of NULL.
> 
> Signed-off-by: Joerg Roedel <jroedel@suse.de>

Thanks for the patch,
Acked-by: Suman Anna <s-anna@ti.com>

regards
Suman

> ---
>  drivers/iommu/omap-iommu.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
> index 95dfca3..641e035 100644
> --- a/drivers/iommu/omap-iommu.c
> +++ b/drivers/iommu/omap-iommu.c
> @@ -1309,7 +1309,7 @@ static void omap_iommu_remove_device(struct device *dev)
>  static struct iommu_group *omap_iommu_device_group(struct device *dev)
>  {
>  	struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
> -	struct iommu_group *group = NULL;
> +	struct iommu_group *group = ERR_PTR(-EINVAL);
>  
>  	if (arch_data->iommu_dev)
>  		group = arch_data->iommu_dev->group;
> 

[PATCH 3/3] iommu: Warn once when device_group callback returns NULL

[Joerg Roedel]

From: Joerg Roedel <jroedel@suse.de>

This callback should never return NULL. Print a warning if
that happens so that we notice and can fix it.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
 drivers/iommu/iommu.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index de09e1e..3f6ea16 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1010,6 +1010,9 @@ struct iommu_group *iommu_group_get_for_dev(struct device *dev)
 	if (ops && ops->device_group)
 		group = ops->device_group(dev);
 
+	if (WARN_ON_ONCE(group == NULL))
+		return ERR_PTR(-EINVAL);
+
 	if (IS_ERR(group))
 		return group;
 
-- 
2.7.4

Re: [PATCH 1/3] iommu: Return ERR_PTR() values from device_group call-backs

[Gerald Schaefer]

On Wed, 28 Jun 2017 14:00:56 +0200
Joerg Roedel <joro@8bytes.org> wrote:

> From: Joerg Roedel <jroedel@suse.de>
> 
> The generic device_group call-backs in iommu.c return NULL
> in case of error. Since they are getting ERR_PTR values from
> iommu_group_alloc(), just pass them up instead.
> 
> Reported-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
> Signed-off-by: Joerg Roedel <jroedel@suse.de>
> ---

Looks good,
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>


>  drivers/iommu/iommu.c | 14 ++------------
>  1 file changed, 2 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
> index cf7ca7e..de09e1e 100644
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -915,13 +915,7 @@ static int get_pci_alias_or_group(struct pci_dev *pdev, u16 alias, void *opaque)
>   */
>  struct iommu_group *generic_device_group(struct device *dev)
>  {
> -	struct iommu_group *group;
> -
> -	group = iommu_group_alloc();
> -	if (IS_ERR(group))
> -		return NULL;
> -
> -	return group;
> +	return iommu_group_alloc();
>  }
> 
>  /*
> @@ -988,11 +982,7 @@ struct iommu_group *pci_device_group(struct device *dev)
>  		return group;
> 
>  	/* No shared group found, allocate new */
> -	group = iommu_group_alloc();
> -	if (IS_ERR(group))
> -		return NULL;
> -
> -	return group;
> +	return iommu_group_alloc();
>  }
> 
>  /**