From 0a4377de305684c883bf90ad21e3cbdeead70f5c Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Tue, 19 May 2015 17:07:14 +0800 Subject: genirq: Introduce irq_set_vcpu_affinity() to target an interrupt to a VCPU With Posted-Interrupts support in Intel CPU and IOMMU, an external interrupt from assigned-devices could be directly delivered to a virtual CPU in a virtual machine. Instead of hacking KVM and Intel IOMMU drivers, we propose a platform independent interface to target an interrupt to a specific virtual CPU in a virtual machine, or set virtual CPU affinity for an interrupt. By adopting this new interface and the hierarchy irqdomain, we could easily support posted-interrupts on Intel platforms, and also provide flexible enough interfaces for other platforms to support similar features. Here is the usage scenario for this interface: Guest update MSI/MSI-X interrupt configuration -->QEMU and KVM handle this -->KVM call this interface (passing posted interrupts descriptor and guest vector) -->irq core will transfer the control to IOMMU -->IOMMU will do the real work of updating IRTE (IRTE has new format for VT-d Posted-Interrupts) Signed-off-by: Jiang Liu Signed-off-by: Feng Wu Link: http://lkml.kernel.org/r/1432026437-16560-2-git-send-email-feng.wu@intel.com Signed-off-by: Thomas Gleixner --- kernel/irq/chip.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'kernel/irq/chip.c') diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index eb9a4ea394ab..55016b2151f3 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -949,6 +949,20 @@ int irq_chip_retrigger_hierarchy(struct irq_data *data) return -ENOSYS; } +/** + * irq_chip_set_vcpu_affinity_parent - Set vcpu affinity on the parent interrupt + * @data: Pointer to interrupt specific data + * @dest: The vcpu affinity information + */ +int irq_chip_set_vcpu_affinity_parent(struct irq_data *data, void *vcpu_info) +{ + data = data->parent_data; + if (data->chip->irq_set_vcpu_affinity) + return data->chip->irq_set_vcpu_affinity(data, vcpu_info); + + return -ENOSYS; +} + /** * irq_chip_set_wake_parent - Set/reset wake-up on the parent interrupt * @data: Pointer to interrupt specific data -- cgit v1.2.3-55-g7522