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authorPunit Agrawal <punit.agrawal@arm.com>2018-12-11 17:10:38 +0000
committerMarc Zyngier <marc.zyngier@arm.com>2018-12-18 15:14:48 +0000
commit86d1c55ea605025f78d026e7fc3a2bb4c3fc2d6a (patch)
tree8b99ba93dd40ac0b23aaf618ca673dead925bd37 /virt/kvm
parent4ea5af53114091e23a8fc279f25637e6c4e892c6 (diff)
downloadlinux-86d1c55ea605025f78d026e7fc3a2bb4c3fc2d6a.tar.bz2
KVM: arm64: Support PUD hugepage in stage2_is_exec()
In preparation for creating PUD hugepages at stage 2, add support for detecting execute permissions on PUD page table entries. Faults due to lack of execute permissions on page table entries is used to perform i-cache invalidation on first execute. Provide trivial implementations of arm32 helpers to allow sharing of code. Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> [ Replaced BUG() => WARN_ON(1) in arm32 PUD helpers ] Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'virt/kvm')
-rw-r--r--virt/kvm/arm/mmu.c53
1 files changed, 48 insertions, 5 deletions
diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index 1c669c3c1208..8e44dccd1b47 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -1083,23 +1083,66 @@ static int stage2_set_pmd_huge(struct kvm *kvm, struct kvm_mmu_memory_cache
return 0;
}
-static bool stage2_is_exec(struct kvm *kvm, phys_addr_t addr)
+/*
+ * stage2_get_leaf_entry - walk the stage2 VM page tables and return
+ * true if a valid and present leaf-entry is found. A pointer to the
+ * leaf-entry is returned in the appropriate level variable - pudpp,
+ * pmdpp, ptepp.
+ */
+static bool stage2_get_leaf_entry(struct kvm *kvm, phys_addr_t addr,
+ pud_t **pudpp, pmd_t **pmdpp, pte_t **ptepp)
{
+ pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
- pmdp = stage2_get_pmd(kvm, NULL, addr);
+ *pudpp = NULL;
+ *pmdpp = NULL;
+ *ptepp = NULL;
+
+ pudp = stage2_get_pud(kvm, NULL, addr);
+ if (!pudp || stage2_pud_none(kvm, *pudp) || !stage2_pud_present(kvm, *pudp))
+ return false;
+
+ if (stage2_pud_huge(kvm, *pudp)) {
+ *pudpp = pudp;
+ return true;
+ }
+
+ pmdp = stage2_pmd_offset(kvm, pudp, addr);
if (!pmdp || pmd_none(*pmdp) || !pmd_present(*pmdp))
return false;
- if (pmd_thp_or_huge(*pmdp))
- return kvm_s2pmd_exec(pmdp);
+ if (pmd_thp_or_huge(*pmdp)) {
+ *pmdpp = pmdp;
+ return true;
+ }
ptep = pte_offset_kernel(pmdp, addr);
if (!ptep || pte_none(*ptep) || !pte_present(*ptep))
return false;
- return kvm_s2pte_exec(ptep);
+ *ptepp = ptep;
+ return true;
+}
+
+static bool stage2_is_exec(struct kvm *kvm, phys_addr_t addr)
+{
+ pud_t *pudp;
+ pmd_t *pmdp;
+ pte_t *ptep;
+ bool found;
+
+ found = stage2_get_leaf_entry(kvm, addr, &pudp, &pmdp, &ptep);
+ if (!found)
+ return false;
+
+ if (pudp)
+ return kvm_s2pud_exec(pudp);
+ else if (pmdp)
+ return kvm_s2pmd_exec(pmdp);
+ else
+ return kvm_s2pte_exec(ptep);
}
static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,