kvm-irqchip: x86: add msi route notify fn

One more IEC notifier is added to let msi routes know about the IEC
changes. When interrupt invalidation happens, all registered msi routes
will be updated for all PCI devices.

Since both vfio and vhost are possible gsi route consumers, this patch
will go one step further to keep them safe in split irqchip mode and
when irqfd is enabled.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
[move trace-events lines into target-i386/trace-events]
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 8875034500..61f57f9f20 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -36,6 +36,7 @@
 #include "hw/i386/apic_internal.h"
 #include "hw/i386/apic-msidef.h"
 #include "hw/i386/intel_iommu.h"
+#include "hw/i386/x86-iommu.h"
 
 #include "exec/ioport.h"
 #include "standard-headers/asm-x86/hyperv.h"
@@ -3413,9 +3414,26 @@ struct MSIRouteEntry {
 static QLIST_HEAD(, MSIRouteEntry) msi_route_list = \
     QLIST_HEAD_INITIALIZER(msi_route_list);
 
+static void kvm_update_msi_routes_all(void *private, bool global,
+                                      uint32_t index, uint32_t mask)
+{
+    int cnt = 0;
+    MSIRouteEntry *entry;
+    MSIMessage msg;
+    /* TODO: explicit route update */
+    QLIST_FOREACH(entry, &msi_route_list, list) {
+        cnt++;
+        msg = pci_get_msi_message(entry->dev, entry->vector);
+        kvm_irqchip_update_msi_route(kvm_state, entry->virq,
+                                     msg, entry->dev);
+    }
+    trace_kvm_x86_update_msi_routes(cnt);
+}
+
 int kvm_arch_add_msi_route_post(struct kvm_irq_routing_entry *route,
                                 int vector, PCIDevice *dev)
 {
+    static bool notify_list_inited = false;
     MSIRouteEntry *entry;
 
     if (!dev) {
@@ -3432,6 +3450,18 @@ int kvm_arch_add_msi_route_post(struct kvm_irq_routing_entry *route,
     QLIST_INSERT_HEAD(&msi_route_list, entry, list);
 
     trace_kvm_x86_add_msi_route(route->gsi);
+
+    if (!notify_list_inited) {
+        /* For the first time we do add route, add ourselves into
+         * IOMMU's IEC notify list if needed. */
+        X86IOMMUState *iommu = x86_iommu_get_default();
+        if (iommu) {
+            x86_iommu_iec_register_notifier(iommu,
+                                            kvm_update_msi_routes_all,
+                                            NULL);
+        }
+        notify_list_inited = true;
+    }
     return 0;
 }