Re: [virtio-dev] [RFC PATCH v2 1/5] iommu: Add virtio-iommu driver - Jean-Philippe Brucker

From: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
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Subject: Re: [virtio-dev] [RFC PATCH v2 1/5] iommu: Add virtio-iommu driver
Date: Wed, 29 Nov 2017 15:17:40 +0000	[thread overview]
Message-ID: <73427923-e62a-e277-42a2-cd37141fa122__41129.7977356755$1511968488$gmane$org@arm.com> (raw)
In-Reply-To: <20171117185211.32593-2-jean-philippe.brucker@arm.com>

On 17/11/17 18:52, Jean-Philippe Brucker wrote:
[...]
> +struct viommu_domain {
> +	struct iommu_domain		domain;
> +	struct viommu_dev		*viommu;
> +	struct mutex			mutex;
> +	unsigned int			id;
> +
> +	spinlock_t			mappings_lock;
> +	struct rb_root_cached		mappings;
> +
> +	/* Number of endpoints attached to this domain */
> +	refcount_t			endpoints;

Refcount_t is the wrong tool for this, I went back to an unsigned int (and
rebased onto v4.15-rc1), on branch virtio-iommu/base.

Thanks,
Jean