/*
* Copyright (C) 2016 - ARM Ltd
*
* stage2 page table helpers
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*/
#ifndef __ARM64_S2_PGTABLE_H_
#define __ARM64_S2_PGTABLE_H_
#include
#include
/*
* PGDIR_SHIFT determines the size a top-level page table entry can map
* and depends on the number of levels in the page table. Compute the
* PGDIR_SHIFT for a given number of levels.
*/
#define pt_levels_pgdir_shift(lvls) ARM64_HW_PGTABLE_LEVEL_SHIFT(4 - (lvls))
/*
* The hardware supports concatenation of up to 16 tables at stage2 entry level
* and we use the feature whenever possible.
*
* Now, the minimum number of bits resolved at any level is (PAGE_SHIFT - 3).
* On arm64, the smallest PAGE_SIZE supported is 4k, which means
* (PAGE_SHIFT - 3) > 4 holds for all page sizes.
* This implies, the total number of page table levels at stage2 expected
* by the hardware is actually the number of levels required for (IPA_SHIFT - 4)
* in normal translations(e.g, stage1), since we cannot have another level in
* the range (IPA_SHIFT, IPA_SHIFT - 4).
*/
#define stage2_pgtable_levels(ipa) ARM64_HW_PGTABLE_LEVELS((ipa) - 4)
#define STAGE2_PGTABLE_LEVELS stage2_pgtable_levels(KVM_PHYS_SHIFT)
#define kvm_stage2_levels(kvm) stage2_pgtable_levels(kvm_phys_shift(kvm))
/*
* With all the supported VA_BITs and 40bit guest IPA, the following condition
* is always true:
*
* STAGE2_PGTABLE_LEVELS <= CONFIG_PGTABLE_LEVELS
*
* We base our stage-2 page table walker helpers on this assumption and
* fall back to using the host version of the helper wherever possible.
* i.e, if a particular level is not folded (e.g, PUD) at stage2, we fall back
* to using the host version, since it is guaranteed it is not folded at host.
*
* If the condition breaks in the future, we can rearrange the host level
* definitions and reuse them for stage2. Till then...
*/
#if STAGE2_PGTABLE_LEVELS > CONFIG_PGTABLE_LEVELS
#error "Unsupported combination of guest IPA and host VA_BITS."
#endif
/* stage2_pgdir_shift() is the size mapped by top-level stage2 entry for the VM */
#define stage2_pgdir_shift(kvm) pt_levels_pgdir_shift(kvm_stage2_levels(kvm))
#define stage2_pgdir_size(kvm) (1ULL << stage2_pgdir_shift(kvm))
#define stage2_pgdir_mask(kvm) ~(stage2_pgdir_size(kvm) - 1)
/*
* The number of PTRS across all concatenated stage2 tables given by the
* number of bits resolved at the initial level.
*/
#define __s2_pgd_ptrs(ipa, lvls) (1 << ((ipa) - pt_levels_pgdir_shift((lvls))))
#define __s2_pgd_size(ipa, lvls) (__s2_pgd_ptrs((ipa), (lvls)) * sizeof(pgd_t))
#define stage2_pgd_ptrs(kvm) __s2_pgd_ptrs(kvm_phys_shift(kvm), kvm_stage2_levels(kvm))
#define stage2_pgd_size(kvm) __s2_pgd_size(kvm_phys_shift(kvm), kvm_stage2_levels(kvm))
/*
* kvm_mmmu_cache_min_pages() is the number of pages required to install
* a stage-2 translation. We pre-allocate the entry level page table at
* the VM creation.
*/
#define kvm_mmu_cache_min_pages(kvm) (kvm_stage2_levels(kvm) - 1)
/* Stage2 PUD definitions when the level is present */
static inline bool kvm_stage2_has_pud(struct kvm *kvm)
{
return (CONFIG_PGTABLE_LEVELS > 3) && (kvm_stage2_levels(kvm) > 3);
}
#define S2_PUD_SHIFT ARM64_HW_PGTABLE_LEVEL_SHIFT(1)
#define S2_PUD_SIZE (1UL << S2_PUD_SHIFT)
#define S2_PUD_MASK (~(S2_PUD_SIZE - 1))
static inline bool stage2_pgd_none(struct kvm *kvm, pgd_t pgd)
{
if (kvm_stage2_has_pud(kvm))
return pgd_none(pgd);
else
return 0;
}
static inline void stage2_pgd_clear(struct kvm *kvm, pgd_t *pgdp)
{
if (kvm_stage2_has_pud(kvm))
pgd_clear(pgdp);
}
static inline bool stage2_pgd_present(struct kvm *kvm, pgd_t pgd)
{
if (kvm_stage2_has_pud(kvm))
return pgd_present(pgd);
else
return 1;
}
static inline void stage2_pgd_populate(struct kvm *kvm, pgd_t *pgd, pud_t *pud)
{
if (kvm_stage2_has_pud(kvm))
pgd_populate(NULL, pgd, pud);
}
static inline pud_t *stage2_pud_offset(struct kvm *kvm,
pgd_t *pgd, unsigned long address)
{
if (kvm_stage2_has_pud(kvm))
return pud_offset(pgd, address);
else
return (pud_t *)pgd;
}
static inline void stage2_pud_free(struct kvm *kvm, pud_t *pud)
{
if (kvm_stage2_has_pud(kvm))
pud_free(NULL, pud);
}
static inline bool stage2_pud_table_empty(struct kvm *kvm, pud_t *pudp)
{
if (kvm_stage2_has_pud(kvm))
return kvm_page_empty(pudp);
else
return false;
}
static inline phys_addr_t
stage2_pud_addr_end(struct kvm *kvm, phys_addr_t addr, phys_addr_t end)
{
if (kvm_stage2_has_pud(kvm)) {
phys_addr_t boundary = (addr + S2_PUD_SIZE) & S2_PUD_MASK;
return (boundary - 1 < end - 1) ? boundary : end;
} else {
return end;
}
}
/* Stage2 PMD definitions when the level is present */
static inline bool kvm_stage2_has_pmd(struct kvm *kvm)
{
return (CONFIG_PGTABLE_LEVELS > 2) && (kvm_stage2_levels(kvm) > 2);
}
#define S2_PMD_SHIFT ARM64_HW_PGTABLE_LEVEL_SHIFT(2)
#define S2_PMD_SIZE (1UL << S2_PMD_SHIFT)
#define S2_PMD_MASK (~(S2_PMD_SIZE - 1))
static inline bool stage2_pud_none(struct kvm *kvm, pud_t pud)
{
if (kvm_stage2_has_pmd(kvm))
return pud_none(pud);
else
return 0;
}
static inline void stage2_pud_clear(struct kvm *kvm, pud_t *pud)
{
if (kvm_stage2_has_pmd(kvm))
pud_clear(pud);
}
static inline bool stage2_pud_present(struct kvm *kvm, pud_t pud)
{
if (kvm_stage2_has_pmd(kvm))
return pud_present(pud);
else
return 1;
}
static inline void stage2_pud_populate(struct kvm *kvm, pud_t *pud, pmd_t *pmd)
{
if (kvm_stage2_has_pmd(kvm))
pud_populate(NULL, pud, pmd);
}
static inline pmd_t *stage2_pmd_offset(struct kvm *kvm,
pud_t *pud, unsigned long address)
{
if (kvm_stage2_has_pmd(kvm))
return pmd_offset(pud, address);
else
return (pmd_t *)pud;
}
static inline void stage2_pmd_free(struct kvm *kvm, pmd_t *pmd)
{
if (kvm_stage2_has_pmd(kvm))
pmd_free(NULL, pmd);
}
static inline bool stage2_pud_huge(struct kvm *kvm, pud_t pud)
{
if (kvm_stage2_has_pmd(kvm))
return pud_huge(pud);
else
return 0;
}
static inline bool stage2_pmd_table_empty(struct kvm *kvm, pmd_t *pmdp)
{
if (kvm_stage2_has_pmd(kvm))
return kvm_page_empty(pmdp);
else
return 0;
}
static inline phys_addr_t
stage2_pmd_addr_end(struct kvm *kvm, phys_addr_t addr, phys_addr_t end)
{
if (kvm_stage2_has_pmd(kvm)) {
phys_addr_t boundary = (addr + S2_PMD_SIZE) & S2_PMD_MASK;
return (boundary - 1 < end - 1) ? boundary : end;
} else {
return end;
}
}
static inline bool stage2_pte_table_empty(struct kvm *kvm, pte_t *ptep)
{
return kvm_page_empty(ptep);
}
static inline unsigned long stage2_pgd_index(struct kvm *kvm, phys_addr_t addr)
{
return (((addr) >> stage2_pgdir_shift(kvm)) & (stage2_pgd_ptrs(kvm) - 1));
}
static inline phys_addr_t
stage2_pgd_addr_end(struct kvm *kvm, phys_addr_t addr, phys_addr_t end)
{
phys_addr_t boundary = (addr + stage2_pgdir_size(kvm)) & stage2_pgdir_mask(kvm);
return (boundary - 1 < end - 1) ? boundary : end;
}
#endif /* __ARM64_S2_PGTABLE_H_ */