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 23f34034db..4a6790d53b 100644 --- a/target/arm/kvm64.c +++ b/target/arm/kvm64.c @@ -1608,3 +1608,27 @@ 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 eb81b7059e..1b94dbe7c8 100644 --- a/target/arm/kvm_arm.h +++ b/target/arm/kvm_arm.h @@ -358,6 +358,8 @@ 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