[PATCH v2 4/6] KVM: arm/arm64: Consolidate page-table accessors

Marc Zyngier
2018-05-30T12:47:04Z

The arm and arm64 KVM page tables accessors are pointlessly different
between the two architectures, and likely both wrong one way or another:
arm64 lacks a dsb(), and arm doesn't use WRITE_ONCE.

Let's unify them.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm/include/asm/kvm_mmu.h | 12 -----------
arch/arm64/include/asm/kvm_mmu.h | 3 ---
virt/kvm/arm/mmu.c | 35 ++++++++++++++++++++++++++++----
3 files changed, 31 insertions(+), 19 deletions(-)

diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h
index 707a1f06dc5d..468ff945efa0 100644
--- a/arch/arm/include/asm/kvm_mmu.h
+++ b/arch/arm/include/asm/kvm_mmu.h
@@ -75,18 +75,6 @@ phys_addr_t kvm_get_idmap_vector(void);
int kvm_mmu_init(void);
void kvm_clear_hyp_idmap(void);

-static inline void kvm_set_pmd(pmd_t *pmd, pmd_t new_pmd)
-{
- *pmd = new_pmd;
- dsb(ishst);
-}
-
-static inline void kvm_set_pte(pte_t *pte, pte_t new_pte)
-{
- *pte = new_pte;
- dsb(ishst);
-}
-
static inline pte_t kvm_s2pte_mkwrite(pte_t pte)
{
pte_val(pte) |= L_PTE_S2_RDWR;
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index 9dbca5355029..26c89b63f604 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -170,9 +170,6 @@ phys_addr_t kvm_get_idmap_vector(void);
int kvm_mmu_init(void);
void kvm_clear_hyp_idmap(void);

-#define kvm_set_pte(ptep, pte) set_pte(ptep, pte)
-#define kvm_set_pmd(pmdp, pmd) set_pmd(pmdp, pmd)
-
static inline pte_t kvm_s2pte_mkwrite(pte_t pte)
{
pte_val(pte) |= PTE_S2_RDWR;
diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index ba66bf7ae299..c9ed239c0840 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -177,6 +177,33 @@ static void clear_stage2_pmd_entry(struct kvm *kvm, pmd_t *pmd, phys_addr_t addr
put_page(virt_to_page(pmd));
}

+static inline void kvm_set_pte(pte_t *ptep, pte_t new_pte)
+{
+ WRITE_ONCE(*ptep, new_pte);
+ dsb(ishst);
+}
+
+static inline void kvm_set_pmd(pmd_t *pmdp, pmd_t new_pmd)
+{
+ WRITE_ONCE(*pmdp, new_pmd);
+ dsb(ishst);
+}
+
+static inline void kvm_pmd_populate(pmd_t *pmdp, pte_t *ptep)
+{
+ pmd_populate_kernel(NULL, pmdp, ptep);
+}
+
+static inline void kvm_pud_populate(pud_t *pudp, pmd_t *pmdp)
+{
+ pud_populate(NULL, pudp, pmdp);
+}
+
+static inline void kvm_pgd_populate(pgd_t *pgdp, pud_t *pudp)
+{
+ pgd_populate(NULL, pgdp, pudp);
+}
+
/*
* Unmapping vs dcache management:
*
@@ -603,7 +630,7 @@ static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
kvm_err("Cannot allocate Hyp pte\n");
return -ENOMEM;
}
- pmd_populate_kernel(NULL, pmd, pte);
+ kvm_pmd_populate(pmd, pte);
get_page(virt_to_page(pmd));
kvm_flush_dcache_to_poc(pmd, sizeof(*pmd));
}
@@ -636,7 +663,7 @@ static int create_hyp_pud_mappings(pgd_t *pgd, unsigned long start,
kvm_err("Cannot allocate Hyp pmd\n");
return -ENOMEM;
}
- pud_populate(NULL, pud, pmd);
+ kvm_pud_populate(pud, pmd);
get_page(virt_to_page(pud));
kvm_flush_dcache_to_poc(pud, sizeof(*pud));
}
@@ -673,7 +700,7 @@ static int __create_hyp_mappings(pgd_t *pgdp, unsigned long ptrs_per_pgd,
err = -ENOMEM;
goto out;
}
- pgd_populate(NULL, pgd, pud);
+ kvm_pgd_populate(pgd, pud);
get_page(virt_to_page(pgd));
kvm_flush_dcache_to_poc(pgd, sizeof(*pgd));
}
@@ -1092,7 +1119,7 @@ static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
if (!cache)
return 0; /* ignore calls from kvm_set_spte_hva */
pte = mmu_memory_cache_alloc(cache);
- pmd_populate_kernel(NULL, pmd, pte);
+ kvm_pmd_populate(pmd, pte);
get_page(virt_to_page(pmd));
}

--
2.17.1