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authorPaolo Bonzini <pbonzini@redhat.com>2016-08-04 13:59:56 +0200
committerPaolo Bonzini <pbonzini@redhat.com>2016-08-04 13:59:56 +0200
commit6f49b2f3414622d3e41135a65dac98968956662b (patch)
treeefd4c358a40b9e6adb9dd35de3407bbf17bd2935 /Documentation
parentabe9efa79be02cf2ba27f643b214b07877bb050b (diff)
parent89581f06b2bc225f0c9822fa52e714aa2e3810dd (diff)
downloadlinux-6f49b2f3414622d3e41135a65dac98968956662b.tar.bz2
Merge tag 'kvm-arm-for-4.8-take2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/ARM Changes for v4.8 - Take 2 Includes GSI routing support to go along with the new VGIC and a small fix that has been cooking in -next for a while.
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/virtual/kvm/api.txt46
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