@samitouri / QOSamiQemu / commits / 49b2dcbd24

accel/accel-irq: add generic begin_route_changes

A generic accel_irqchip_begin_route_change() fn has been introduced for usage in the MSHV accelerator. It replaces the respective kvm_ fn. Signed-off-by: Magnus Kulke <magnuskulke@linux.microsoft.com> Link: https://lore.kernel.org/r/20260417105618.3621-6-magnuskulke@linux.microsoft.com Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Magnus Kulke committed Apr 17, 2026 at 12:55 UTC 49b2dcbd2422b4039ef4e566b212950dc5e7d211
7 files changed +30 -14
accel/accel-irq.c
+21
@@ -10,6 +10,7 @@
10 */
11
12 #include "qemu/osdep.h"
13 +#include "qemu/error-report.h"
14 #include "hw/pci/msi.h"
15
16 #include "system/kvm.h"
@@ -104,3 +105,23 @@ int accel_irqchip_remove_irqfd_notifier_gsi(EventNotifier *n, int virq)
105 }
106 return -ENOSYS;
107 }
108 +
109 +inline AccelRouteChange accel_irqchip_begin_route_changes(void)
110 +{
111 +#ifdef CONFIG_MSHV_IS_POSSIBLE
112 + if (mshv_msi_via_irqfd_enabled()) {
113 + return (AccelRouteChange) {
114 + .accel = ACCEL(mshv_state),
115 + .changes = 0,
116 + };
117 + }
118 +#endif
119 + if (kvm_enabled()) {
120 + return (AccelRouteChange) {
121 + .accel = ACCEL(kvm_state),
122 + .changes = 0,
123 + };
124 + }
125 + error_report("can't initiate route change, no accel irqchip available");
126 + abort();
127 +}
hw/misc/ivshmem-pci.c
+2 -2
@@ -26,7 +26,7 @@
26 #include "hw/core/qdev-properties-system.h"
27 #include "hw/pci/msi.h"
28 #include "hw/pci/msix.h"
29 -#include "system/kvm.h"
29 +#include "system/accel-irq.h"
30 #include "migration/blocker.h"
31 #include "migration/vmstate.h"
32 #include "qemu/error-report.h"
@@ -430,7 +430,7 @@ static void ivshmem_add_kvm_msi_virq(IVShmemState *s, int vector,
430 IVSHMEM_DPRINTF("ivshmem_add_kvm_msi_virq vector:%d\n", vector);
431 assert(!s->msi_vectors[vector].pdev);
432
433 - c = kvm_irqchip_begin_route_changes(kvm_state);
433 + c = accel_irqchip_begin_route_changes();
434 ret = kvm_irqchip_add_msi_route(&c, vector, pdev);
435 if (ret < 0) {
436 error_setg(errp, "kvm_irqchip_add_msi_route failed");
hw/vfio/pci.c
+3 -2
@@ -38,6 +38,7 @@
38 #include "qemu/module.h"
39 #include "qemu/range.h"
40 #include "qemu/units.h"
41 +#include "system/accel-irq.h"
42 #include "system/kvm.h"
43 #include "system/runstate.h"
44 #include "pci.h"
@@ -688,7 +689,7 @@ static int vfio_msix_vector_do_use(PCIDevice *pdev, unsigned int nr,
689 if (vdev->defer_kvm_irq_routing) {
690 vfio_pci_add_kvm_msi_virq(vdev, vector, nr, true);
691 } else {
691 - vfio_route_change = kvm_irqchip_begin_route_changes(kvm_state);
692 + vfio_route_change = accel_irqchip_begin_route_changes();
693 vfio_pci_add_kvm_msi_virq(vdev, vector, nr, true);
694 kvm_irqchip_commit_route_changes(&vfio_route_change);
695 vfio_connect_kvm_msi_virq(vector, nr);
@@ -789,7 +790,7 @@ void vfio_pci_prepare_kvm_msi_virq_batch(VFIOPCIDevice *vdev)
790 {
791 assert(!vdev->defer_kvm_irq_routing);
792 vdev->defer_kvm_irq_routing = true;
792 - vfio_route_change = kvm_irqchip_begin_route_changes(kvm_state);
793 + vfio_route_change = accel_irqchip_begin_route_changes();
794 }
795
796 void vfio_pci_commit_kvm_msi_virq_batch(VFIOPCIDevice *vdev)
hw/virtio/virtio-pci.c
+1 -1
@@ -869,7 +869,7 @@ static int kvm_virtio_pci_vq_vector_use(VirtIOPCIProxy *proxy,
869 int ret;
870
871 if (irqfd->users == 0) {
872 - AccelRouteChange c = kvm_irqchip_begin_route_changes(kvm_state);
872 + AccelRouteChange c = accel_irqchip_begin_route_changes();
873 ret = accel_irqchip_add_msi_route(&c, vector, &proxy->pci_dev);
874 if (ret < 0) {
875 return ret;
include/system/accel-irq.h
+1
@@ -25,6 +25,7 @@ static inline bool accel_irqchip_is_split(void)
25 return mshv_msi_via_irqfd_enabled() || kvm_irqchip_is_split();
26 }
27
28 +AccelRouteChange accel_irqchip_begin_route_changes(void);
29 int accel_irqchip_add_msi_route(AccelRouteChange *c, int vector,
30 PCIDevice *dev);
31 int accel_irqchip_update_msi_route(int vector, MSIMessage msg, PCIDevice *dev);
include/system/kvm.h
-8
@@ -476,14 +476,6 @@ int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg,
476 PCIDevice *dev);
477 void kvm_irqchip_commit_routes(KVMState *s);
478
479 -static inline AccelRouteChange kvm_irqchip_begin_route_changes(KVMState *s)
480 -{
481 - return (AccelRouteChange) {
482 - .accel = ACCEL(s),
483 - .changes = 0,
484 - };
485 -}
486 -
479 static inline void kvm_irqchip_commit_route_changes(AccelRouteChange *c)
480 {
481 if (c->changes) {
target/i386/kvm/kvm.c
+2 -1
@@ -32,6 +32,7 @@
32 #include "vmsr_energy.h"
33 #include "system/system.h"
34 #include "system/hw_accel.h"
35 +#include "system/accel-irq.h"
36 #include "system/kvm_int.h"
37 #include "system/runstate.h"
38 #include "system/ramblock.h"
@@ -6678,7 +6679,7 @@ void kvm_arch_init_irq_routing(KVMState *s)
6679 kvm_gsi_routing_allowed = true;
6680
6681 if (kvm_irqchip_is_split()) {
6681 - AccelRouteChange c = kvm_irqchip_begin_route_changes(s);
6682 + AccelRouteChange c = accel_irqchip_begin_route_changes();
6683 int i;
6684
6685 /* If the ioapic is in QEMU and the lapics are in KVM, reserve