[PATCH v3 05/21] KVM: arm64: Expose page-table helpers

From: Quentin Perret
Date: Thu Jul 29 2021 - 09:28:46 EST


The KVM pgtable API exposes the kvm_pgtable_walk() function to allow
the definition of walkers outside of pgtable.c. However, it is not easy
to implement any of those walkers without some of the low-level helpers.
Move some of them to the header file to allow re-use from other places.

Signed-off-by: Quentin Perret <qperret@xxxxxxxxxx>
---
arch/arm64/include/asm/kvm_pgtable.h | 40 ++++++++++++++++++++++++++++
arch/arm64/kvm/hyp/pgtable.c | 39 ---------------------------
2 files changed, 40 insertions(+), 39 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h
index 082b9d65f40b..6938eac72c1f 100644
--- a/arch/arm64/include/asm/kvm_pgtable.h
+++ b/arch/arm64/include/asm/kvm_pgtable.h
@@ -25,6 +25,46 @@ static inline u64 kvm_get_parange(u64 mmfr0)

typedef u64 kvm_pte_t;

+#define KVM_PTE_VALID BIT(0)
+
+#define KVM_PTE_ADDR_MASK GENMASK(47, PAGE_SHIFT)
+#define KVM_PTE_ADDR_51_48 GENMASK(15, 12)
+
+static inline bool kvm_pte_valid(kvm_pte_t pte)
+{
+ return pte & KVM_PTE_VALID;
+}
+
+static inline 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 inline u64 kvm_granule_shift(u32 level)
+{
+ /* Assumes KVM_PGTABLE_MAX_LEVELS is 4 */
+ return ARM64_HW_PGTABLE_LEVEL_SHIFT(level);
+}
+
+static inline u64 kvm_granule_size(u32 level)
+{
+ return BIT(kvm_granule_shift(level));
+}
+
+static inline 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));
+}
+
/**
* struct kvm_pgtable_mm_ops - Memory management callbacks.
* @zalloc_page: Allocate a single zeroed memory page.
diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c
index 78f36bd5df6c..49d768b92997 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)
@@ -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;
--
2.32.0.432.gabb21c7263-goog