Re: [PATCH v10 06/18] iommufd/device: Add helper to detect the first attach of a group

[Baolu Lu <baolu.lu@linux.intel.com>]

On 3/20/25 21:47, Yi Liu wrote:
> The existing code detects the first attach by checking the
> igroup->device_list. However, the igroup->hwpt can also be used to detect
> the first attach. In future modifications, it is better to check the
> igroup->hwpt instead of the device_list. To improve readbility and also
> prepare for further modifications on this part, this adds a helper for it.
> 
> Signed-off-by: Yi Liu<yi.l.liu@intel.com>
> ---
> v9 -> v10: It is patch 07 of v9, it's reworked hence renamed as well.
> ---
>   drivers/iommu/iommufd/device.c | 11 +++++++++--
>   1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c
> index ac54d734b819..9db36346328f 100644
> --- a/drivers/iommu/iommufd/device.c
> +++ b/drivers/iommu/iommufd/device.c
> @@ -444,6 +444,13 @@ static int iommufd_group_setup_msi(struct iommufd_group *igroup,
>   	return 0;
>   }
>   
> +static inline bool
> +igroup_first_attach(struct iommufd_group *igroup, ioasid_t pasid)
> +{
> +	lockdep_assert_held(&igroup->lock);
> +	return !igroup->hwpt;
> +}

Nit: avoid inline helpers in the C file. Others look good to me.

Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>