++ more migration experts! On Mon, 8 Feb 2021 at 11:20, Haibo Xu <haibo...@linaro.org> wrote: > > 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 >