Commit e5359dcc authored by Jason Gunthorpe's avatar Jason Gunthorpe Committed by Joerg Roedel
Browse files

iommupt: Add a mock pagetable format for iommufd selftest to use 



The iommufd self test uses an xarray to store the pfns and their orders to
emulate a page table. Slightly modify the amdv1 page table to create a
real page table that has similar properties:

 - 2k base granule to simulate something like a 4k page table on a 64K
   PAGE_SIZE ARM system
 - Contiguous page support for every PFN order
 - Dirty tracking

AMDv1 is the closest format, as it is the only one that already supports
every page size. Tweak it to have only 5 levels and an 11 bit base granule
and compile it separately as a format variant.

Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Reviewed-by: default avatarSamiullah Khawaja <skhawaja@google.com>
Tested-by: default avatarAlejandro Jimenez <alejandro.j.jimenez@oracle.com>
Tested-by: default avatarPasha Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Signed-off-by: default avatarJoerg Roedel <joerg.roedel@amd.com>
parent 1dd4187f

drivers/iommu/generic_pt/fmt/Makefile

+1 −0
Original line number Diff line number Diff line 
# SPDX-License-Identifier: GPL-2.0



iommu_pt_fmt-$(CONFIG_IOMMU_PT_AMDV1) += amdv1

iommu_pt_fmt-$(CONFIG_IOMMUFD_TEST) += mock



IOMMU_PT_KUNIT_TEST :=

define create_format

drivers/iommu/generic_pt/fmt/amdv1.h

+16 −2
Original line number Diff line number Diff line
@@ -26,11 +26,23 @@ 
#include <linux/string.h>



enum {

	PT_MAX_OUTPUT_ADDRESS_LG2 = 52,

	PT_MAX_VA_ADDRESS_LG2 = 64,

	PT_ITEM_WORD_SIZE = sizeof(u64),

	/*

	 * The IOMMUFD selftest uses the AMDv1 format with some alterations It

	 * uses a 2k page size to test cases where the CPU page size is not the

	 * same.

	 */

#ifdef AMDV1_IOMMUFD_SELFTEST

	PT_MAX_VA_ADDRESS_LG2 = 56,

	PT_MAX_OUTPUT_ADDRESS_LG2 = 51,

	PT_MAX_TOP_LEVEL = 4,

	PT_GRANULE_LG2SZ = 11,

#else

	PT_MAX_VA_ADDRESS_LG2 = 64,

	PT_MAX_OUTPUT_ADDRESS_LG2 = 52,

	PT_MAX_TOP_LEVEL = 5,

	PT_GRANULE_LG2SZ = 12,

#endif

	PT_TABLEMEM_LG2SZ = 12,



	/* The DTE only has these bits for the top phyiscal address */
@@ -374,6 +386,7 @@ static inline int amdv1pt_iommu_fmt_init(struct pt_iommu_amdv1 *iommu_table, 
}

#define pt_iommu_fmt_init amdv1pt_iommu_fmt_init



#ifndef PT_FMT_VARIANT

static inline void

amdv1pt_iommu_fmt_hw_info(struct pt_iommu_amdv1 *table,

			  const struct pt_range *top_range,
@@ -384,6 +397,7 @@ amdv1pt_iommu_fmt_hw_info(struct pt_iommu_amdv1 *table, 
	info->mode = top_range->top_level + 1;

}

#define pt_iommu_fmt_hw_info amdv1pt_iommu_fmt_hw_info

#endif



#if defined(GENERIC_PT_KUNIT)

static const struct pt_iommu_amdv1_cfg amdv1_kunit_fmt_cfgs[] = {

drivers/iommu/generic_pt/fmt/iommu_mock.c

0 → 100644
+10 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only

/*

 * Copyright (c) 2024-2025, NVIDIA CORPORATION & AFFILIATES

 */

#define AMDV1_IOMMUFD_SELFTEST 1

#define PT_FMT amdv1

#define PT_FMT_VARIANT mock

#define PT_SUPPORTED_FEATURES 0



#include "iommu_template.h"

include/linux/generic_pt/iommu.h

+6 −0
Original line number Diff line number Diff line
@@ -237,6 +237,12 @@ struct pt_iommu_amdv1_hw_info { 


IOMMU_FORMAT(amdv1, amdpt);



/* amdv1_mock is used by the iommufd selftest */

#define pt_iommu_amdv1_mock pt_iommu_amdv1

#define pt_iommu_amdv1_mock_cfg pt_iommu_amdv1_cfg

struct pt_iommu_amdv1_mock_hw_info;

IOMMU_PROTOTYPES(amdv1_mock);



#undef IOMMU_PROTOTYPES

#undef IOMMU_FORMAT

#endif