diff options
Diffstat (limited to 'arch/arm64/kvm/hyp/pgtable.c')
| -rw-r--r-- | arch/arm64/kvm/hyp/pgtable.c | 247 |
1 files changed, 124 insertions, 123 deletions
diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index 05321f4165e3..f8ceebe4982e 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -11,16 +11,12 @@ #include <asm/kvm_pgtable.h> #include <asm/stage2_pgtable.h> -#define KVM_PTE_VALID BIT(0) #define KVM_PTE_TYPE BIT(1) #define KVM_PTE_TYPE_BLOCK 0 #define KVM_PTE_TYPE_PAGE 1 #define KVM_PTE_TYPE_TABLE 1 -#define KVM_PTE_ADDR_MASK GENMASK(47, PAGE_SHIFT) -#define KVM_PTE_ADDR_51_48 GENMASK(15, 12) - #define KVM_PTE_LEAF_ATTR_LO GENMASK(11, 2) #define KVM_PTE_LEAF_ATTR_LO_S1_ATTRIDX GENMASK(4, 2) @@ -40,6 +36,8 @@ #define KVM_PTE_LEAF_ATTR_HI GENMASK(63, 51) +#define KVM_PTE_LEAF_ATTR_HI_SW GENMASK(58, 55) + #define KVM_PTE_LEAF_ATTR_HI_S1_XN BIT(54) #define KVM_PTE_LEAF_ATTR_HI_S2_XN BIT(54) @@ -48,9 +46,7 @@ KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W | \ KVM_PTE_LEAF_ATTR_HI_S2_XN) -#define KVM_PTE_LEAF_ATTR_S2_IGNORED GENMASK(58, 55) - -#define KVM_INVALID_PTE_OWNER_MASK GENMASK(63, 56) +#define KVM_INVALID_PTE_OWNER_MASK GENMASK(9, 2) #define KVM_MAX_OWNER_ID 1 struct kvm_pgtable_walk_data { @@ -61,17 +57,6 @@ struct kvm_pgtable_walk_data { u64 end; }; -static u64 kvm_granule_shift(u32 level) -{ - /* Assumes KVM_PGTABLE_MAX_LEVELS is 4 */ - return ARM64_HW_PGTABLE_LEVEL_SHIFT(level); -} - -static u64 kvm_granule_size(u32 level) -{ - return BIT(kvm_granule_shift(level)); -} - #define KVM_PHYS_INVALID (-1ULL) static bool kvm_phys_is_valid(u64 phys) @@ -79,15 +64,6 @@ static bool kvm_phys_is_valid(u64 phys) return phys < BIT(id_aa64mmfr0_parange_to_phys_shift(ID_AA64MMFR0_PARANGE_MAX)); } -static bool kvm_level_supports_block_mapping(u32 level) -{ - /* - * Reject invalid block mappings and don't bother with 4TB mappings for - * 52-bit PAs. - */ - return !(level == 0 || (PAGE_SIZE != SZ_4K && level == 1)); -} - static bool kvm_block_mapping_supported(u64 addr, u64 end, u64 phys, u32 level) { u64 granule = kvm_granule_size(level); @@ -135,11 +111,6 @@ static u32 kvm_pgd_pages(u32 ia_bits, u32 start_level) return __kvm_pgd_page_idx(&pgt, -1ULL) + 1; } -static bool kvm_pte_valid(kvm_pte_t pte) -{ - return pte & KVM_PTE_VALID; -} - static bool kvm_pte_table(kvm_pte_t pte, u32 level) { if (level == KVM_PGTABLE_MAX_LEVELS - 1) @@ -151,16 +122,6 @@ static bool kvm_pte_table(kvm_pte_t pte, u32 level) return FIELD_GET(KVM_PTE_TYPE, pte) == KVM_PTE_TYPE_TABLE; } -static u64 kvm_pte_to_phys(kvm_pte_t pte) -{ - u64 pa = pte & KVM_PTE_ADDR_MASK; - - if (PAGE_SHIFT == 16) - pa |= FIELD_GET(KVM_PTE_ADDR_51_48, pte) << 48; - - return pa; -} - static kvm_pte_t kvm_phys_to_pte(u64 pa) { kvm_pte_t pte = pa & KVM_PTE_ADDR_MASK; @@ -326,6 +287,45 @@ int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size, return _kvm_pgtable_walk(&walk_data); } +struct leaf_walk_data { + kvm_pte_t pte; + u32 level; +}; + +static int leaf_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, + enum kvm_pgtable_walk_flags flag, void * const arg) +{ + struct leaf_walk_data *data = arg; + + data->pte = *ptep; + data->level = level; + + return 0; +} + +int kvm_pgtable_get_leaf(struct kvm_pgtable *pgt, u64 addr, + kvm_pte_t *ptep, u32 *level) +{ + struct leaf_walk_data data; + struct kvm_pgtable_walker walker = { + .cb = leaf_walker, + .flags = KVM_PGTABLE_WALK_LEAF, + .arg = &data, + }; + int ret; + + ret = kvm_pgtable_walk(pgt, ALIGN_DOWN(addr, PAGE_SIZE), + PAGE_SIZE, &walker); + if (!ret) { + if (ptep) + *ptep = data.pte; + if (level) + *level = data.level; + } + + return ret; +} + struct hyp_map_data { u64 phys; kvm_pte_t attr; @@ -357,11 +357,47 @@ static int hyp_set_prot_attr(enum kvm_pgtable_prot prot, kvm_pte_t *ptep) attr |= FIELD_PREP(KVM_PTE_LEAF_ATTR_LO_S1_AP, ap); attr |= FIELD_PREP(KVM_PTE_LEAF_ATTR_LO_S1_SH, sh); attr |= KVM_PTE_LEAF_ATTR_LO_S1_AF; + attr |= prot & KVM_PTE_LEAF_ATTR_HI_SW; *ptep = attr; return 0; } +enum kvm_pgtable_prot kvm_pgtable_hyp_pte_prot(kvm_pte_t pte) +{ + enum kvm_pgtable_prot prot = pte & KVM_PTE_LEAF_ATTR_HI_SW; + u32 ap; + + if (!kvm_pte_valid(pte)) + return prot; + + if (!(pte & KVM_PTE_LEAF_ATTR_HI_S1_XN)) + prot |= KVM_PGTABLE_PROT_X; + + ap = FIELD_GET(KVM_PTE_LEAF_ATTR_LO_S1_AP, pte); + if (ap == KVM_PTE_LEAF_ATTR_LO_S1_AP_RO) + prot |= KVM_PGTABLE_PROT_R; + else if (ap == KVM_PTE_LEAF_ATTR_LO_S1_AP_RW) + prot |= KVM_PGTABLE_PROT_RW; + + return prot; +} + +static bool hyp_pte_needs_update(kvm_pte_t old, kvm_pte_t new) +{ + /* + * Tolerate KVM recreating the exact same mapping, or changing software + * bits if the existing mapping was valid. + */ + if (old == new) + return false; + + if (!kvm_pte_valid(old)) + return true; + + return !WARN_ON((old ^ new) & ~KVM_PTE_LEAF_ATTR_HI_SW); +} + static bool hyp_map_walker_try_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, struct hyp_map_data *data) { @@ -371,9 +407,8 @@ static bool hyp_map_walker_try_leaf(u64 addr, u64 end, u32 level, if (!kvm_block_mapping_supported(addr, end, phys, level)) return false; - /* Tolerate KVM recreating the exact same mapping */ new = kvm_init_valid_leaf_pte(phys, data->attr, level); - if (old != new && !WARN_ON(kvm_pte_valid(old))) + if (hyp_pte_needs_update(old, new)) smp_store_release(ptep, new); data->phys += granule; @@ -438,6 +473,8 @@ int kvm_pgtable_hyp_init(struct kvm_pgtable *pgt, u32 va_bits, pgt->start_level = KVM_PGTABLE_MAX_LEVELS - levels; pgt->mm_ops = mm_ops; pgt->mmu = NULL; + pgt->force_pte_cb = NULL; + return 0; } @@ -475,6 +512,9 @@ struct stage2_map_data { void *memcache; struct kvm_pgtable_mm_ops *mm_ops; + + /* Force mappings to page granularity */ + bool force_pte; }; u64 kvm_get_vtcr(u64 mmfr0, u64 mmfr1, u32 phys_shift) @@ -539,11 +579,29 @@ static int stage2_set_prot_attr(struct kvm_pgtable *pgt, enum kvm_pgtable_prot p attr |= FIELD_PREP(KVM_PTE_LEAF_ATTR_LO_S2_SH, sh); attr |= KVM_PTE_LEAF_ATTR_LO_S2_AF; + attr |= prot & KVM_PTE_LEAF_ATTR_HI_SW; *ptep = attr; return 0; } +enum kvm_pgtable_prot kvm_pgtable_stage2_pte_prot(kvm_pte_t pte) +{ + enum kvm_pgtable_prot prot = pte & KVM_PTE_LEAF_ATTR_HI_SW; + + if (!kvm_pte_valid(pte)) + return prot; + + if (pte & KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R) + prot |= KVM_PGTABLE_PROT_R; + if (pte & KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W) + prot |= KVM_PGTABLE_PROT_W; + if (!(pte & KVM_PTE_LEAF_ATTR_HI_S2_XN)) + prot |= KVM_PGTABLE_PROT_X; + + return prot; +} + static bool stage2_pte_needs_update(kvm_pte_t old, kvm_pte_t new) { if (!kvm_pte_valid(old) || !kvm_pte_valid(new)) @@ -588,6 +646,15 @@ static bool stage2_pte_executable(kvm_pte_t pte) return !(pte & KVM_PTE_LEAF_ATTR_HI_S2_XN); } +static bool stage2_leaf_mapping_allowed(u64 addr, u64 end, u32 level, + struct stage2_map_data *data) +{ + if (data->force_pte && (level < (KVM_PGTABLE_MAX_LEVELS - 1))) + return false; + + return kvm_block_mapping_supported(addr, end, data->phys, level); +} + static int stage2_map_walker_try_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, struct stage2_map_data *data) @@ -597,7 +664,7 @@ static int stage2_map_walker_try_leaf(u64 addr, u64 end, u32 level, struct kvm_pgtable *pgt = data->mmu->pgt; struct kvm_pgtable_mm_ops *mm_ops = data->mm_ops; - if (!kvm_block_mapping_supported(addr, end, phys, level)) + if (!stage2_leaf_mapping_allowed(addr, end, level, data)) return -E2BIG; if (kvm_phys_is_valid(phys)) @@ -641,7 +708,7 @@ static int stage2_map_walk_table_pre(u64 addr, u64 end, u32 level, if (data->anchor) return 0; - if (!kvm_block_mapping_supported(addr, end, data->phys, level)) + if (!stage2_leaf_mapping_allowed(addr, end, level, data)) return 0; data->childp = kvm_pte_follow(*ptep, data->mm_ops); @@ -771,6 +838,7 @@ int kvm_pgtable_stage2_map(struct kvm_pgtable *pgt, u64 addr, u64 size, .mmu = pgt->mmu, .memcache = mc, .mm_ops = pgt->mm_ops, + .force_pte = pgt->force_pte_cb && pgt->force_pte_cb(addr, addr + size, prot), }; struct kvm_pgtable_walker walker = { .cb = stage2_map_walker, @@ -802,6 +870,7 @@ int kvm_pgtable_stage2_set_owner(struct kvm_pgtable *pgt, u64 addr, u64 size, .memcache = mc, .mm_ops = pgt->mm_ops, .owner_id = owner_id, + .force_pte = true, }; struct kvm_pgtable_walker walker = { .cb = stage2_map_walker, @@ -995,6 +1064,9 @@ int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, u32 level; kvm_pte_t set = 0, clr = 0; + if (prot & KVM_PTE_LEAF_ATTR_HI_SW) + return -EINVAL; + if (prot & KVM_PGTABLE_PROT_R) set |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R; @@ -1043,9 +1115,11 @@ int kvm_pgtable_stage2_flush(struct kvm_pgtable *pgt, u64 addr, u64 size) return kvm_pgtable_walk(pgt, addr, size, &walker); } -int kvm_pgtable_stage2_init_flags(struct kvm_pgtable *pgt, struct kvm_arch *arch, - struct kvm_pgtable_mm_ops *mm_ops, - enum kvm_pgtable_stage2_flags flags) + +int __kvm_pgtable_stage2_init(struct kvm_pgtable *pgt, struct kvm_arch *arch, + struct kvm_pgtable_mm_ops *mm_ops, + enum kvm_pgtable_stage2_flags flags, + kvm_pgtable_force_pte_cb_t force_pte_cb) { size_t pgd_sz; u64 vtcr = arch->vtcr; @@ -1063,6 +1137,7 @@ int kvm_pgtable_stage2_init_flags(struct kvm_pgtable *pgt, struct kvm_arch *arch pgt->mm_ops = mm_ops; pgt->mmu = &arch->mmu; pgt->flags = flags; + pgt->force_pte_cb = force_pte_cb; /* Ensure zeroed PGD pages are visible to the hardware walker */ dsb(ishst); @@ -1102,77 +1177,3 @@ void kvm_pgtable_stage2_destroy(struct kvm_pgtable *pgt) pgt->mm_ops->free_pages_exact(pgt->pgd, pgd_sz); pgt->pgd = NULL; } - -#define KVM_PTE_LEAF_S2_COMPAT_MASK (KVM_PTE_LEAF_ATTR_S2_PERMS | \ - KVM_PTE_LEAF_ATTR_LO_S2_MEMATTR | \ - KVM_PTE_LEAF_ATTR_S2_IGNORED) - -static int stage2_check_permission_walker(u64 addr, u64 end, u32 level, - kvm_pte_t *ptep, - enum kvm_pgtable_walk_flags flag, - void * const arg) -{ - kvm_pte_t old_attr, pte = *ptep, *new_attr = arg; - - /* - * Compatible mappings are either invalid and owned by the page-table - * owner (whose id is 0), or valid with matching permission attributes. - */ - if (kvm_pte_valid(pte)) { - old_attr = pte & KVM_PTE_LEAF_S2_COMPAT_MASK; - if (old_attr != *new_attr) - return -EEXIST; - } else if (pte) { - return -EEXIST; - } - - return 0; -} - -int kvm_pgtable_stage2_find_range(struct kvm_pgtable *pgt, u64 addr, - enum kvm_pgtable_prot prot, - struct kvm_mem_range *range) -{ - kvm_pte_t attr; - struct kvm_pgtable_walker check_perm_walker = { - .cb = stage2_check_permission_walker, - .flags = KVM_PGTABLE_WALK_LEAF, - .arg = &attr, - }; - u64 granule, start, end; - u32 level; - int ret; - - ret = stage2_set_prot_attr(pgt, prot, &attr); - if (ret) - return ret; - attr &= KVM_PTE_LEAF_S2_COMPAT_MASK; - - for (level = pgt->start_level; level < KVM_PGTABLE_MAX_LEVELS; level++) { - granule = kvm_granule_size(level); - start = ALIGN_DOWN(addr, granule); - end = start + granule; - - if (!kvm_level_supports_block_mapping(level)) - continue; - - if (start < range->start || range->end < end) - continue; - - /* - * Check the presence of existing mappings with incompatible - * permissions within the current block range, and try one level - * deeper if one is found. - */ - ret = kvm_pgtable_walk(pgt, start, granule, &check_perm_walker); - if (ret != -EEXIST) - break; - } - - if (!ret) { - range->start = start; - range->end = end; - } - - return ret; -} |