Commit 4cbf3851 authored by Sai Praneeth Prakhya's avatar Sai Praneeth Prakhya Committed by Joerg Roedel
Browse files

iommu: Add def_domain_type() callback in iommu_ops 



Some devices are reqired to use a specific type (identity or dma)
of default domain when they are used with a vendor iommu. When the
system level default domain type is different from it, the vendor
iommu driver has to request a new default domain with
iommu_request_dma_domain_for_dev() and iommu_request_dm_for_dev()
in the add_dev() callback. Unfortunately, these two helpers only
work when the group hasn't been assigned to any other devices,
hence, some vendor iommu driver has to use a private domain if
it fails to request a new default one.

This adds def_domain_type() callback in the iommu_ops, so that
any special requirement of default domain for a device could be
aware by the iommu generic layer.

Signed-off-by: default avatarSai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
[ jroedel@suse.de: Added iommu_get_def_domain_type() function and use
                   it to allocate the default domain ]
Co-developed-by: default avatarJoerg Roedel <jroedel@suse.de>
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
Tested-by: default avatarMarek Szyprowski <m.szyprowski@samsung.com>
Acked-by: default avatarMarek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20200429133712.31431-3-joro@8bytes.org


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent ff2a08b3

drivers/iommu/iommu.c

+17 −3
Original line number Original line Diff line number Diff line
@@ -1361,21 +1361,35 @@ struct iommu_group *fsl_mc_device_group(struct device *dev) 
}

}

EXPORT_SYMBOL_GPL(fsl_mc_device_group);

EXPORT_SYMBOL_GPL(fsl_mc_device_group);





static int iommu_get_def_domain_type(struct device *dev)

{

	const struct iommu_ops *ops = dev->bus->iommu_ops;

	unsigned int type = 0;



	if (ops->def_domain_type)

		type = ops->def_domain_type(dev);



	return (type == 0) ? iommu_def_domain_type : type;

}



static int iommu_alloc_default_domain(struct device *dev,

static int iommu_alloc_default_domain(struct device *dev,

				      struct iommu_group *group)

				      struct iommu_group *group)

{

{

	struct iommu_domain *dom;

	struct iommu_domain *dom;

	unsigned int type;





	if (group->default_domain)

	if (group->default_domain)

		return 0;

		return 0;





	dom = __iommu_domain_alloc(dev->bus, iommu_def_domain_type);

	type = iommu_get_def_domain_type(dev);

	if (!dom && iommu_def_domain_type != IOMMU_DOMAIN_DMA) {



	dom = __iommu_domain_alloc(dev->bus, type);

	if (!dom && type != IOMMU_DOMAIN_DMA) {

		dom = __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_DMA);

		dom = __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_DMA);

		if (dom) {

		if (dom) {

			dev_warn(dev,

			dev_warn(dev,

				 "failed to allocate default IOMMU domain of type %u; falling back to IOMMU_DOMAIN_DMA",

				 "failed to allocate default IOMMU domain of type %u; falling back to IOMMU_DOMAIN_DMA",

				 iommu_def_domain_type);

				 type);

		}

		}

	}

	}

include/linux/iommu.h

+6 −0
Original line number Original line Diff line number Diff line
@@ -248,6 +248,10 @@ struct iommu_iotlb_gather { 
 * @cache_invalidate: invalidate translation caches

 * @cache_invalidate: invalidate translation caches

 * @sva_bind_gpasid: bind guest pasid and mm

 * @sva_bind_gpasid: bind guest pasid and mm

 * @sva_unbind_gpasid: unbind guest pasid and mm

 * @sva_unbind_gpasid: unbind guest pasid and mm

 * @def_domain_type: device default domain type, return value:

 *		- IOMMU_DOMAIN_IDENTITY: must use an identity domain

 *		- IOMMU_DOMAIN_DMA: must use a dma domain

 *		- 0: use the default setting

 * @pgsize_bitmap: bitmap of all possible supported page sizes

 * @pgsize_bitmap: bitmap of all possible supported page sizes

 * @owner: Driver module providing these ops

 * @owner: Driver module providing these ops

 */

 */
@@ -318,6 +322,8 @@ struct iommu_ops { 




	int (*sva_unbind_gpasid)(struct device *dev, int pasid);

	int (*sva_unbind_gpasid)(struct device *dev, int pasid);





	int (*def_domain_type)(struct device *dev);



	unsigned long pgsize_bitmap;

	unsigned long pgsize_bitmap;

	struct module *owner;

	struct module *owner;

};

};

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