This control is to be used by the H_INT_RESET hcall from QEMU. Its
purpose is to clear all configuration of the sources and EQs. This is
necessary in case of a kexec (for a kdump kernel for instance) to make
sure that no remaining configuration is left from the previous boot
setup so that the new kernel can start safely from a clean state.
The queue 7 is ignored when the KVM device is configured to run in
single escalation mode. Prio 7 is used by escalations.
The XIVE VP is kept enabled as the vCPU is still active and connected
to the XIVE device.
Signed-off-by: Cédric Le Goater <clg@xxxxxxxx>
---
arch/powerpc/include/uapi/asm/kvm.h | 1 +
arch/powerpc/kvm/book3s_xive_native.c | 82 ++++++++++++++++++++++
Documentation/virtual/kvm/devices/xive.txt | 5 ++
3 files changed, 88 insertions(+)
diff --git a/arch/powerpc/include/uapi/asm/kvm.h b/arch/powerpc/include/uapi/asm/kvm.h
index 177e43f3edaf..7ae8cb22af7d 100644
--- a/arch/powerpc/include/uapi/asm/kvm.h
+++ b/arch/powerpc/include/uapi/asm/kvm.h
@@ -677,6 +677,7 @@ struct kvm_ppc_cpu_char {
/* POWER9 XIVE Native Interrupt Controller */
#define KVM_DEV_XIVE_GRP_CTRL 1
+#define KVM_DEV_XIVE_RESET 1
#define KVM_DEV_XIVE_GRP_SOURCE 2 /* 64-bit source attributes */
#define KVM_DEV_XIVE_GRP_SOURCE_CONFIG 3 /* 64-bit source attributes */
#define KVM_DEV_XIVE_GRP_EQ_CONFIG 4 /* 64-bit eq attributes */
diff --git a/arch/powerpc/kvm/book3s_xive_native.c b/arch/powerpc/kvm/book3s_xive_native.c
index 34a35bcf550c..bb3e121c918a 100644
--- a/arch/powerpc/kvm/book3s_xive_native.c
+++ b/arch/powerpc/kvm/book3s_xive_native.c
@@ -536,6 +536,80 @@ static int kvmppc_xive_native_get_queue_config(struct kvmppc_xive *xive,
return 0;
}
+static void kvmppc_xive_reset_sources(struct kvmppc_xive_src_block *sb)
+{
+ int i;
+
+ for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) {
+ struct kvmppc_xive_irq_state *state = &sb->irq_state[i];
+
+ if (!state->valid)
+ continue;
+
+ if (state->act_priority == MASKED)
+ continue;
+
+ arch_spin_lock(&sb->lock);
+ state->eisn = 0;
+ state->act_server = 0;
+ state->act_priority = MASKED;
+ xive_vm_esb_load(&state->ipi_data, XIVE_ESB_SET_PQ_01);
+ xive_native_configure_irq(state->ipi_number, 0, MASKED, 0);
+ if (state->pt_number) {
+ xive_vm_esb_load(state->pt_data, XIVE_ESB_SET_PQ_01);
+ xive_native_configure_irq(state->pt_number,
+ 0, MASKED, 0);
+ }
+ arch_spin_unlock(&sb->lock);
+ }
+}
+
+static int kvmppc_xive_reset(struct kvmppc_xive *xive)
+{
+ struct kvm *kvm = xive->kvm;
+ struct kvm_vcpu *vcpu;
+ unsigned int i;
+
+ pr_devel("%s\n", __func__);
+
+ mutex_lock(&kvm->lock);
+
+ kvm_for_each_vcpu(i, vcpu, kvm) {
+ struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
+ unsigned int prio;
+
+ if (!xc)
+ continue;
+
+ kvmppc_xive_disable_vcpu_interrupts(vcpu);
+
+ for (prio = 0; prio < KVMPPC_XIVE_Q_COUNT; prio++) {
+
+ /* Single escalation, no queue 7 */
+ if (prio == 7 && xive->single_escalation)
+ break;
+
+ if (xc->esc_virq[prio]) {
+ free_irq(xc->esc_virq[prio], vcpu);
+ irq_dispose_mapping(xc->esc_virq[prio]);
+ kfree(xc->esc_virq_names[prio]);
+ xc->esc_virq[prio] = 0;
+ }
+
+ kvmppc_xive_native_cleanup_queue(vcpu, prio);
+ }
+ }
+
+ for (i = 0; i <= xive->max_sbid; i++) {
+ if (xive->src_blocks[i])
+ kvmppc_xive_reset_sources(xive->src_blocks[i]);
+ }
+
+ mutex_unlock(&kvm->lock);
+
+ return 0;
+}
+
static int kvmppc_xive_native_set_attr(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
@@ -543,6 +617,10 @@ static int kvmppc_xive_native_set_attr(struct kvm_device *dev,
switch (attr->group) {
case KVM_DEV_XIVE_GRP_CTRL:
+ switch (attr->attr) {
+ case KVM_DEV_XIVE_RESET:
+ return kvmppc_xive_reset(xive);
+ }
break;
case KVM_DEV_XIVE_GRP_SOURCE:
return kvmppc_xive_native_set_source(xive, attr->attr,
@@ -575,6 +653,10 @@ static int kvmppc_xive_native_has_attr(struct kvm_device *dev,
{
switch (attr->group) {
case KVM_DEV_XIVE_GRP_CTRL:
+ switch (attr->attr) {
+ case KVM_DEV_XIVE_RESET:
+ return 0;
+ }
break;
case KVM_DEV_XIVE_GRP_SOURCE:
case KVM_DEV_XIVE_GRP_SOURCE_CONFIG:
diff --git a/Documentation/virtual/kvm/devices/xive.txt b/Documentation/virtual/kvm/devices/xive.txt
index c0b5d9bd43fb..f1d007f485a9 100644
--- a/Documentation/virtual/kvm/devices/xive.txt
+++ b/Documentation/virtual/kvm/devices/xive.txt
@@ -17,6 +17,11 @@ the legacy interrupt mode, referred as XICS (POWER7/8).
1. KVM_DEV_XIVE_GRP_CTRL
Provides global controls on the device
+ Attributes:
+ 1.1 KVM_DEV_XIVE_RESET (write only)
+ Resets the interrupt controller configuration for sources and event
+ queues. To be used by kexec and kdump.
+ Errors: none
2. KVM_DEV_XIVE_GRP_SOURCE (write only)
Initializes a new source in the XIVE device and mask it.
--
2.20.1
