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Diffstat (limited to 'arch/arm64/kvm/hyp/pgtable.c')
-rw-r--r--arch/arm64/kvm/hyp/pgtable.c247
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;
-}
generated by cgit v1.2.3 (git 2.39.1) at 2025-01-28 22:05:51 +0100