The SMCCC call filtering provide the ability to forward the SMCCC call
to userspace, so we provide a new option `user-smccc` to enable handling
SMCCC call in userspace, the default value is off.
And add the skeleton implementation for userspace SMCCC call
initialization and handling.
Signed-off-by: Shaoqin Huang <shahuang@xxxxxxxxxx>
---
docs/system/arm/virt.rst | 4 +++
hw/arm/virt.c | 21 ++++++++++++++++
include/hw/arm/virt.h | 1 +
target/arm/kvm.c | 54 ++++++++++++++++++++++++++++++++++++++++
4 files changed, 80 insertions(+)
diff --git a/docs/system/arm/virt.rst b/docs/system/arm/virt.rst
index 1cab33f02e..ff43d52f04 100644
--- a/docs/system/arm/virt.rst
+++ b/docs/system/arm/virt.rst
@@ -155,6 +155,10 @@ dtb-randomness
DTB to be non-deterministic. It would be the responsibility of
the firmware to come up with a seed and pass it on if it wants to.
+user-smccc
+ Set ``on``/``off`` to enable/disable handling smccc call in userspace
+ instead of kernel.
+
dtb-kaslr-seed
A deprecated synonym for dtb-randomness.
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 9b9f7d9c68..767720321c 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -42,6 +42,7 @@
#include "hw/vfio/vfio-amd-xgbe.h"
#include "hw/display/ramfb.h"
#include "net/net.h"
+#include "qom/object.h"
#include "sysemu/device_tree.h"
#include "sysemu/numa.h"
#include "sysemu/runstate.h"
@@ -2511,6 +2512,19 @@ static void virt_set_oem_table_id(Object *obj, const char *value,
strncpy(vms->oem_table_id, value, 8);
}
+static bool virt_get_user_smccc(Object *obj, Error **errp)
+{
+ VirtMachineState *vms = VIRT_MACHINE(obj);
+
+ return vms->user_smccc;
+}
+
+static void virt_set_user_smccc(Object *obj, bool value, Error **errp)
+{
+ VirtMachineState *vms = VIRT_MACHINE(obj);
+
+ vms->user_smccc = value;
+}
bool virt_is_acpi_enabled(VirtMachineState *vms)
{
@@ -3155,6 +3169,13 @@ static void virt_machine_class_init(ObjectClass *oc, void *data)
"in ACPI table header."
"The string may be up to 8 bytes in size");
+ object_class_property_add_bool(oc, "user-smccc",
+ virt_get_user_smccc,
+ virt_set_user_smccc);
+ object_class_property_set_description(oc, "user-smccc",
+ "Set on/off to enable/disable "
+ "handling smccc call in userspace");
+
}
static void virt_instance_init(Object *obj)
diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index e1ddbea96b..4f1bc12680 100644
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -160,6 +160,7 @@ struct VirtMachineState {
bool ras;
bool mte;
bool dtb_randomness;
+ bool user_smccc;
OnOffAuto acpi;
VirtGICType gic_version;
VirtIOMMUType iommu;
diff --git a/target/arm/kvm.c b/target/arm/kvm.c
index 84da49332c..579c6edd49 100644
--- a/target/arm/kvm.c
+++ b/target/arm/kvm.c
@@ -9,6 +9,8 @@
*/
#include "qemu/osdep.h"
+#include <asm-arm64/kvm.h>
+#include <linux/arm-smccc.h>
#include <sys/ioctl.h>
#include <linux/kvm.h>
@@ -247,6 +249,20 @@ int kvm_arm_get_max_vm_ipa_size(MachineState *ms, bool *fixed_ipa)
return ret > 0 ? ret : 40;
}
+static int kvm_arm_init_smccc_filter(KVMState *s)
+{
+ int ret = 0;
+
+ if (kvm_vm_check_attr(s, KVM_ARM_VM_SMCCC_CTRL, KVM_ARM_VM_SMCCC_FILTER)) {
+ error_report("ARM SMCCC filter not supported");
+ ret = -EINVAL;
+ goto out;
+ }
+
+out:
+ return ret;
+}
+
int kvm_arch_init(MachineState *ms, KVMState *s)
{
int ret = 0;
@@ -282,6 +298,10 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
kvm_arm_init_debug(s);
+ if (ret == 0 && object_property_get_bool(OBJECT(ms), "user-smccc", NULL)) {
+ ret = kvm_arm_init_smccc_filter(s);
+ }
+
return ret;
}
@@ -912,6 +932,37 @@ static int kvm_arm_handle_dabt_nisv(CPUState *cs, uint64_t esr_iss,
return -1;
}
+static void kvm_arm_smccc_return_result(CPUState *cs, struct arm_smccc_res *res)
+{
+ ARMCPU *cpu = ARM_CPU(cs);
+ CPUARMState *env = &cpu->env;
+
+ env->xregs[0] = res->a0;
+ env->xregs[1] = res->a1;
+ env->xregs[2] = res->a2;
+ env->xregs[3] = res->a3;
+}
+
+static int kvm_arm_handle_hypercall(CPUState *cs, struct kvm_run *run)
+{
+ uint32_t fn = run->hypercall.nr;
+ struct arm_smccc_res res = {
+ .a0 = SMCCC_RET_NOT_SUPPORTED,
+ };
+ int ret = 0;
+
+ kvm_cpu_synchronize_state(cs);
+
+ switch (ARM_SMCCC_OWNER_NUM(fn)) {
+ default:
+ break;
+ }
+
+ kvm_arm_smccc_return_result(cs, &res);
+
+ return ret;
+}
+
int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run)
{
int ret = 0;
@@ -927,6 +978,9 @@ int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run)
ret = kvm_arm_handle_dabt_nisv(cs, run->arm_nisv.esr_iss,
run->arm_nisv.fault_ipa);
break;
+ case KVM_EXIT_HYPERCALL:
+ ret = kvm_arm_handle_hypercall(cs, run);
+ break;
default:
qemu_log_mask(LOG_UNIMP, "%s: un-handled exit reason %d\n",
__func__, run->exit_reason);
--
2.39.1
