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Message-ID: <77295c8fea08907d82363dedc9ba01b79ac702a2.camel@linux.ibm.com>
Subject: Re: [PATCH v5 2/6] iommu/s390: Get rid of s390_domain_device
From:   Niklas Schnelle <schnelle@linux.ibm.com>
To:     Matthew Rosato <mjrosato@linux.ibm.com>,
        Pierre Morel <pmorel@linux.ibm.com>, iommu@lists.linux.dev
Cc:     linux-s390@vger.kernel.org, borntraeger@linux.ibm.com,
        hca@linux.ibm.com, gor@linux.ibm.com,
        gerald.schaefer@linux.ibm.com, agordeev@linux.ibm.com,
        svens@linux.ibm.com, joro@8bytes.org, will@kernel.org,
        robin.murphy@arm.com, jgg@nvidia.com, linux-kernel@vger.kernel.org
Date:   Thu, 06 Oct 2022 17:19:44 +0200
In-Reply-To: <20221006144700.3380098-3-schnelle@linux.ibm.com>
References: <20221006144700.3380098-1-schnelle@linux.ibm.com>
         <20221006144700.3380098-3-schnelle@linux.ibm.com>
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On Thu, 2022-10-06 at 16:46 +0200, Niklas Schnelle wrote:
> The struct s390_domain_device serves the sole purpose as list entry for
> the devices list of a struct s390_domain. As it contains no additional
> information besides a list_head and a pointer to the struct zpci_dev we
> can simplify things and just thread the device list through struct
> zpci_dev directly. This removes the need to allocate during domain
> attach and gets rid of one level of indirection during mapping
> operations.
> 
> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

@Jason, on second thought not sure if your R-b still holds as you only
implied that the zpci_unregister_ioat(), zdev->dma_table = NULL is okay
with the plan of ignoring zpci_register_ioat() fail on error in the
future (already have the patch).

> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
> ---
>  arch/s390/include/asm/pci.h |  1 +
>  drivers/iommu/s390-iommu.c  | 37 +++++++------------------------------
>  2 files changed, 8 insertions(+), 30 deletions(-)
---8<---