Re: [PATCH v2 13/33] iommu: Export bus_iommu_probe() and make is safe for re-probing

[Lu Baolu]

On 2020/4/14 21:15, Joerg Roedel wrote:
> From: Joerg Roedel <jroedel@xxxxxxx>
>
> Add a check to the bus_iommu_probe() call-path to make sure it ignores
> devices which have already been successfully probed. Then export the
> bus_iommu_probe() function so it can be used by IOMMU drivers.
>
> Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
> ---
>   drivers/iommu/iommu.c | 6 +++++-
>   include/linux/iommu.h | 1 +
>   2 files changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
> index 834a45da0ed0..a2ff95424044 100644
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -1615,6 +1615,10 @@ static int probe_iommu_group(struct device *dev, void *data)
>   	if (!dev_iommu_get(dev))
>   		return -ENOMEM;
>   
> +	/* Device is probed already if in a group */
> +	if (iommu_group_get(dev) != NULL)

Same as
	if (iommu_group_get(dev))
?

By the way, do we need to put the group if device has already been
probed?

Best regards,
baolu