Commit 13646796 authored by Lu Baolu's avatar Lu Baolu Committed by Joerg Roedel
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iommu: Add IOMMU SVA domain support 



The SVA iommu_domain represents a hardware pagetable that the IOMMU
hardware could use for SVA translation. This adds some infrastructures
to support SVA domain in the iommu core. It includes:

- Extend the iommu_domain to support a new IOMMU_DOMAIN_SVA domain
  type. The IOMMU drivers that support allocation of the SVA domain
  should provide its own SVA domain specific iommu_domain_ops.
- Add a helper to allocate an SVA domain. The iommu_domain_free()
  is still used to free an SVA domain.

The report_iommu_fault() should be replaced by the new
iommu_report_device_fault(). Leave the existing fault handler with the
existing users and the newly added SVA members excludes it.

Suggested-by: default avatarJean-Philippe Brucker <jean-philippe@linaro.org>
Suggested-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: default avatarJean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Reviewed-by: default avatarYi Liu <yi.l.liu@intel.com>
Tested-by: default avatarZhangfei Gao <zhangfei.gao@linaro.org>
Tested-by: default avatarTony Zhu <tony.zhu@intel.com>
Link: https://lore.kernel.org/r/20221031005917.45690-7-baolu.lu@linux.intel.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 16603704

drivers/iommu/iommu.c

+20 −0
Original line number Diff line number Diff line
@@ -29,6 +29,7 @@ 
#include <linux/module.h>

#include <linux/cc_platform.h>

#include <trace/events/iommu.h>

#include <linux/sched/mm.h>



#include "dma-iommu.h"
@@ -1934,6 +1935,8 @@ EXPORT_SYMBOL_GPL(iommu_domain_alloc); 


void iommu_domain_free(struct iommu_domain *domain)

{

	if (domain->type == IOMMU_DOMAIN_SVA)

		mmdrop(domain->mm);

	iommu_put_dma_cookie(domain);

	domain->ops->free(domain);

}
@@ -3383,3 +3386,20 @@ struct iommu_domain *iommu_get_domain_for_dev_pasid(struct device *dev, 
	return domain;

}

EXPORT_SYMBOL_GPL(iommu_get_domain_for_dev_pasid);



struct iommu_domain *iommu_sva_domain_alloc(struct device *dev,

					    struct mm_struct *mm)

{

	const struct iommu_ops *ops = dev_iommu_ops(dev);

	struct iommu_domain *domain;



	domain = ops->domain_alloc(IOMMU_DOMAIN_SVA);

	if (!domain)

		return NULL;



	domain->type = IOMMU_DOMAIN_SVA;

	mmgrab(mm);

	domain->mm = mm;



	return domain;

}

include/linux/iommu.h

+23 −2
Original line number Diff line number Diff line
@@ -64,6 +64,8 @@ struct iommu_domain_geometry { 
#define __IOMMU_DOMAIN_PT	(1U << 2)  /* Domain is identity mapped   */

#define __IOMMU_DOMAIN_DMA_FQ	(1U << 3)  /* DMA-API uses flush queue    */



#define __IOMMU_DOMAIN_SVA	(1U << 4)  /* Shared process address space */



/*

 * This are the possible domain-types

 *
@@ -77,6 +79,8 @@ struct iommu_domain_geometry { 
 *				  certain optimizations for these domains

 *	IOMMU_DOMAIN_DMA_FQ	- As above, but definitely using batched TLB

 *				  invalidation.

 *	IOMMU_DOMAIN_SVA	- DMA addresses are shared process addresses

 *				  represented by mm_struct's.

 */

#define IOMMU_DOMAIN_BLOCKED	(0U)

#define IOMMU_DOMAIN_IDENTITY	(__IOMMU_DOMAIN_PT)
@@ -86,15 +90,24 @@ struct iommu_domain_geometry { 
#define IOMMU_DOMAIN_DMA_FQ	(__IOMMU_DOMAIN_PAGING |	\

				 __IOMMU_DOMAIN_DMA_API |	\

				 __IOMMU_DOMAIN_DMA_FQ)

#define IOMMU_DOMAIN_SVA	(__IOMMU_DOMAIN_SVA)



struct iommu_domain {

	unsigned type;

	const struct iommu_domain_ops *ops;

	unsigned long pgsize_bitmap;	/* Bitmap of page sizes in use */

	iommu_fault_handler_t handler;

	void *handler_token;

	struct iommu_domain_geometry geometry;

	struct iommu_dma_cookie *iova_cookie;

	union {

		struct {

			iommu_fault_handler_t handler;

			void *handler_token;

		};

		struct {	/* IOMMU_DOMAIN_SVA */

			struct mm_struct *mm;

			int users;

		};

	};

};



static inline bool iommu_is_dma_domain(struct iommu_domain *domain)
@@ -685,6 +698,8 @@ int iommu_group_claim_dma_owner(struct iommu_group *group, void *owner); 
void iommu_group_release_dma_owner(struct iommu_group *group);

bool iommu_group_dma_owner_claimed(struct iommu_group *group);



struct iommu_domain *iommu_sva_domain_alloc(struct device *dev,

					    struct mm_struct *mm);

int iommu_attach_device_pasid(struct iommu_domain *domain,

			      struct device *dev, ioasid_t pasid);

void iommu_detach_device_pasid(struct iommu_domain *domain,
@@ -1055,6 +1070,12 @@ static inline bool iommu_group_dma_owner_claimed(struct iommu_group *group) 
	return false;

}



static inline struct iommu_domain *

iommu_sva_domain_alloc(struct device *dev, struct mm_struct *mm)

{

	return NULL;

}



static inline int iommu_attach_device_pasid(struct iommu_domain *domain,

					    struct device *dev, ioasid_t pasid)

{