Re: [PATCH v3 1/6] ARM/dma-mapping: Add arm_iommu_release_device()

[Jason Gunthorpe]

On Mon, Mar 06, 2023 at 10:57:59AM +0800, Lu Baolu wrote:
> It is like arm_iommu_detach_device() except it handles the special case
> of being called under an iommu driver's release operation. In this case
> the driver must have already detached the device from any attached
> domain before calling this function.
> 
> Replace arm_iommu_detach_device() with arm_iommu_release_device() in the
> release path of the ipmmu-vmsa driver.
> 
> The bonus is that it also removes a obstacle of arm_iommu_detach_device()
> re-entering the iommu core during release_device. With this removed, the
> iommu core code could be simplified a lot.
> 
> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> ---
>  arch/arm/include/asm/dma-iommu.h |  1 +
>  arch/arm/mm/dma-mapping.c        | 25 +++++++++++++++++++++++++
>  drivers/iommu/ipmmu-vmsa.c       | 15 +++++++++++++--
>  3 files changed, 39 insertions(+), 2 deletions(-)

Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>

Jason