[PATCH V3 2/6] kvm: detect assigned device via irqbypass manager
From: Zhu Lingshan <hidden>
Date: 2020-07-22 10:13:12
Also in:
kvm, virtualization
Subsystem:
kernel virtual machine for x86 (kvm/x86), the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Sean Christopherson, Paolo Bonzini, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
vDPA devices has dedicated backed hardware like passthrough-ed devices. Then it is possible to setup irq offloading to vCPU for vDPA devices. Thus this patch tries to manipulated assigned device counters by kvm_arch_start/end_assignment() in irqbypass manager, so that assigned devices could be detected in update_pi_irte() We will increase/decrease the assigned device counter in kvm/x86. Both vDPA and VFIO would go through this code path. Only X86 uses these counters and kvm_arch_start/end_assignment(), so this code path only affect x86 for now. Signed-off-by: Zhu Lingshan <redacted> --- arch/x86/kvm/x86.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 88c593f83b28..b2bf17f808b6 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c@@ -10630,11 +10630,17 @@ int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, { struct kvm_kernel_irqfd *irqfd = container_of(cons, struct kvm_kernel_irqfd, consumer); + int ret; irqfd->producer = prod; + kvm_arch_start_assignment(irqfd->kvm); + ret = kvm_x86_ops.update_pi_irte(irqfd->kvm, + prod->irq, irqfd->gsi, 1); + + if (ret) + kvm_arch_end_assignment(irqfd->kvm); - return kvm_x86_ops.update_pi_irte(irqfd->kvm, - prod->irq, irqfd->gsi, 1); + return ret; } void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
@@ -10645,6 +10651,7 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, container_of(cons, struct kvm_kernel_irqfd, consumer); WARN_ON(irqfd->producer != prod); + kvm_arch_end_assignment(irqfd->kvm); irqfd->producer = NULL; /*
--
2.18.4