diff options
Diffstat (limited to 'Documentation/virtual/kvm/api.txt')
| -rw-r--r-- | Documentation/virtual/kvm/api.txt | 46 |
1 files changed, 33 insertions, 13 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 5237e1b2fd66..da3c395ed174 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -1433,13 +1433,16 @@ KVM_ASSIGN_DEV_IRQ. Partial deassignment of host or guest IRQ is allowed. 4.52 KVM_SET_GSI_ROUTING Capability: KVM_CAP_IRQ_ROUTING -Architectures: x86 s390 +Architectures: x86 s390 arm arm64 Type: vm ioctl Parameters: struct kvm_irq_routing (in) Returns: 0 on success, -1 on error Sets the GSI routing table entries, overwriting any previously set entries. +On arm/arm64, GSI routing has the following limitation: +- GSI routing does not apply to KVM_IRQ_LINE but only to KVM_IRQFD. + struct kvm_irq_routing { __u32 nr; __u32 flags; @@ -1468,7 +1471,13 @@ struct kvm_irq_routing_entry { #define KVM_IRQ_ROUTING_S390_ADAPTER 3 #define KVM_IRQ_ROUTING_HV_SINT 4 -No flags are specified so far, the corresponding field must be set to zero. +flags: +- KVM_MSI_VALID_DEVID: used along with KVM_IRQ_ROUTING_MSI routing entry + type, specifies that the devid field contains a valid value. The per-VM + KVM_CAP_MSI_DEVID capability advertises the requirement to provide + the device ID. If this capability is not available, userspace should + never set the KVM_MSI_VALID_DEVID flag as the ioctl might fail. +- zero otherwise struct kvm_irq_routing_irqchip { __u32 irqchip; @@ -1479,9 +1488,16 @@ struct kvm_irq_routing_msi { __u32 address_lo; __u32 address_hi; __u32 data; - __u32 pad; + union { + __u32 pad; + __u32 devid; + }; }; +If KVM_MSI_VALID_DEVID is set, devid contains a unique device identifier +for the device that wrote the MSI message. For PCI, this is usually a +BFD identifier in the lower 16 bits. + On x86, address_hi is ignored unless the KVM_X2APIC_API_USE_32BIT_IDS feature of KVM_CAP_X2APIC_API capability is enabled. If it is enabled, address_hi bits 31-8 provide bits 31-8 of the destination id. Bits 7-0 of @@ -2199,14 +2215,14 @@ struct kvm_msi { __u8 pad[12]; }; -flags: KVM_MSI_VALID_DEVID: devid contains a valid value -devid: If KVM_MSI_VALID_DEVID is set, contains a unique device identifier - for the device that wrote the MSI message. - For PCI, this is usually a BFD identifier in the lower 16 bits. +flags: KVM_MSI_VALID_DEVID: devid contains a valid value. The per-VM + KVM_CAP_MSI_DEVID capability advertises the requirement to provide + the device ID. If this capability is not available, userspace + should never set the KVM_MSI_VALID_DEVID flag as the ioctl might fail. -The per-VM KVM_CAP_MSI_DEVID capability advertises the need to provide -the device ID. If this capability is not set, userland cannot rely on -the kernel to allow the KVM_MSI_VALID_DEVID flag being set. +If KVM_MSI_VALID_DEVID is set, devid contains a unique device identifier +for the device that wrote the MSI message. For PCI, this is usually a +BFD identifier in the lower 16 bits. On x86, address_hi is ignored unless the KVM_CAP_X2APIC_API capability is enabled. If it is enabled, address_hi bits 31-8 provide bits 31-8 of the @@ -2383,9 +2399,13 @@ Note that closing the resamplefd is not sufficient to disable the irqfd. The KVM_IRQFD_FLAG_RESAMPLE is only necessary on assignment and need not be specified with KVM_IRQFD_FLAG_DEASSIGN. -On ARM/ARM64, the gsi field in the kvm_irqfd struct specifies the Shared -Peripheral Interrupt (SPI) index, such that the GIC interrupt ID is -given by gsi + 32. +On arm/arm64, gsi routing being supported, the following can happen: +- in case no routing entry is associated to this gsi, injection fails +- in case the gsi is associated to an irqchip routing entry, + irqchip.pin + 32 corresponds to the injected SPI ID. +- in case the gsi is associated to an MSI routing entry, the MSI + message and device ID are translated into an LPI (support restricted + to GICv3 ITS in-kernel emulation). 4.76 KVM_PPC_ALLOCATE_HTAB |