MTE spec provide instructions to retrieve the memory tags:
(1) LDG, at 16 bytes granularity, and available in both user
and kernel space;
(2) LDGM, at 256 bytes granularity in maximum, and only
available in kernel space
To improve the performance, KVM has exposed the LDGM capability
to user space by providing a new APIs. This patch is just a
wrapper for the KVM APIs.
Signed-off-by: Haibo Xu <haibo...@linaro.org>
---
target/arm/kvm64.c | 24 ++++++++++++++++++++++++
target/arm/kvm_arm.h | 2 ++
2 files changed, 26 insertions(+)
diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c
index 73a191f8e1..3157025316 100644
--- a/target/arm/kvm64.c
+++ b/target/arm/kvm64.c
@@ -1606,3 +1606,27 @@ bool kvm_arm_verify_ext_dabt_pending(CPUState *cs)
}
return false;
}
+
+int kvm_arm_mte_get_tags(uint64_t ipa, uint64_t len, uint8_t *buf)
+{
+ struct kvm_arm_copy_mte_tags args = {
+ .guest_ipa = ipa,
+ .length = len,
+ .addr = buf,
+ .flags = KVM_ARM_TAGS_FROM_GUEST,
+ };
+
+ return kvm_vm_ioctl(kvm_state, KVM_ARM_MTE_COPY_TAGS, &args);
+}
+
+int kvm_arm_mte_set_tags(uint64_t ipa, uint64_t len, uint8_t *buf)
+{
+ struct kvm_arm_copy_mte_tags args = {
+ .guest_ipa = ipa,
+ .length = len,
+ .addr = buf,
+ .flags = KVM_ARM_TAGS_TO_GUEST,
+ };
+
+ return kvm_vm_ioctl(kvm_state, KVM_ARM_MTE_COPY_TAGS, &args);
+}
diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
index 34f8daa377..bbb833d6c6 100644
--- a/target/arm/kvm_arm.h
+++ b/target/arm/kvm_arm.h
@@ -360,6 +360,8 @@ int kvm_arm_vgic_probe(void);
void kvm_arm_pmu_set_irq(CPUState *cs, int irq);
void kvm_arm_pmu_init(CPUState *cs);
+int kvm_arm_mte_get_tags(uint64_t ipa, uint64_t len, uint8_t *buf);
+int kvm_arm_mte_set_tags(uint64_t ipa, uint64_t len, uint8_t *buf);
/**
* kvm_arm_pvtime_init:
--
2.17.1
