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-rw-r--r--kernel/Documentation/virtual/kvm/devices/README1
-rw-r--r--kernel/Documentation/virtual/kvm/devices/arm-vgic.txt116
-rw-r--r--kernel/Documentation/virtual/kvm/devices/mpic.txt53
-rw-r--r--kernel/Documentation/virtual/kvm/devices/s390_flic.txt94
-rw-r--r--kernel/Documentation/virtual/kvm/devices/vfio.txt22
-rw-r--r--kernel/Documentation/virtual/kvm/devices/vm.txt85
-rw-r--r--kernel/Documentation/virtual/kvm/devices/xics.txt66
7 files changed, 437 insertions, 0 deletions
diff --git a/kernel/Documentation/virtual/kvm/devices/README b/kernel/Documentation/virtual/kvm/devices/README
new file mode 100644
index 000000000..34a698341
--- /dev/null
+++ b/kernel/Documentation/virtual/kvm/devices/README
@@ -0,0 +1 @@
+This directory contains specific device bindings for KVM_CAP_DEVICE_CTRL.
diff --git a/kernel/Documentation/virtual/kvm/devices/arm-vgic.txt b/kernel/Documentation/virtual/kvm/devices/arm-vgic.txt
new file mode 100644
index 000000000..3fb905429
--- /dev/null
+++ b/kernel/Documentation/virtual/kvm/devices/arm-vgic.txt
@@ -0,0 +1,116 @@
+ARM Virtual Generic Interrupt Controller (VGIC)
+===============================================
+
+Device types supported:
+ KVM_DEV_TYPE_ARM_VGIC_V2 ARM Generic Interrupt Controller v2.0
+ KVM_DEV_TYPE_ARM_VGIC_V3 ARM Generic Interrupt Controller v3.0
+
+Only one VGIC instance may be instantiated through either this API or the
+legacy KVM_CREATE_IRQCHIP api. The created VGIC will act as the VM interrupt
+controller, requiring emulated user-space devices to inject interrupts to the
+VGIC instead of directly to CPUs.
+
+Creating a guest GICv3 device requires a host GICv3 as well.
+GICv3 implementations with hardware compatibility support allow a guest GICv2
+as well.
+
+Groups:
+ KVM_DEV_ARM_VGIC_GRP_ADDR
+ Attributes:
+ KVM_VGIC_V2_ADDR_TYPE_DIST (rw, 64-bit)
+ Base address in the guest physical address space of the GIC distributor
+ register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V2.
+ This address needs to be 4K aligned and the region covers 4 KByte.
+
+ KVM_VGIC_V2_ADDR_TYPE_CPU (rw, 64-bit)
+ Base address in the guest physical address space of the GIC virtual cpu
+ interface register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V2.
+ This address needs to be 4K aligned and the region covers 4 KByte.
+
+ KVM_VGIC_V3_ADDR_TYPE_DIST (rw, 64-bit)
+ Base address in the guest physical address space of the GICv3 distributor
+ register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
+ This address needs to be 64K aligned and the region covers 64 KByte.
+
+ KVM_VGIC_V3_ADDR_TYPE_REDIST (rw, 64-bit)
+ Base address in the guest physical address space of the GICv3
+ redistributor register mappings. There are two 64K pages for each
+ VCPU and all of the redistributor pages are contiguous.
+ Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
+ This address needs to be 64K aligned.
+
+
+ KVM_DEV_ARM_VGIC_GRP_DIST_REGS
+ Attributes:
+ The attr field of kvm_device_attr encodes two values:
+ bits: | 63 .... 40 | 39 .. 32 | 31 .... 0 |
+ values: | reserved | cpu id | offset |
+
+ All distributor regs are (rw, 32-bit)
+
+ The offset is relative to the "Distributor base address" as defined in the
+ GICv2 specs. Getting or setting such a register has the same effect as
+ reading or writing the register on the actual hardware from the cpu
+ specified with cpu id field. Note that most distributor fields are not
+ banked, but return the same value regardless of the cpu id used to access
+ the register.
+ Limitations:
+ - Priorities are not implemented, and registers are RAZ/WI
+ - Currently only implemented for KVM_DEV_TYPE_ARM_VGIC_V2.
+ Errors:
+ -ENODEV: Getting or setting this register is not yet supported
+ -EBUSY: One or more VCPUs are running
+
+ KVM_DEV_ARM_VGIC_GRP_CPU_REGS
+ Attributes:
+ The attr field of kvm_device_attr encodes two values:
+ bits: | 63 .... 40 | 39 .. 32 | 31 .... 0 |
+ values: | reserved | cpu id | offset |
+
+ All CPU interface regs are (rw, 32-bit)
+
+ The offset specifies the offset from the "CPU interface base address" as
+ defined in the GICv2 specs. Getting or setting such a register has the
+ same effect as reading or writing the register on the actual hardware.
+
+ The Active Priorities Registers APRn are implementation defined, so we set a
+ fixed format for our implementation that fits with the model of a "GICv2
+ implementation without the security extensions" which we present to the
+ guest. This interface always exposes four register APR[0-3] describing the
+ maximum possible 128 preemption levels. The semantics of the register
+ indicate if any interrupts in a given preemption level are in the active
+ state by setting the corresponding bit.
+
+ Thus, preemption level X has one or more active interrupts if and only if:
+
+ APRn[X mod 32] == 0b1, where n = X / 32
+
+ Bits for undefined preemption levels are RAZ/WI.
+
+ Limitations:
+ - Priorities are not implemented, and registers are RAZ/WI
+ - Currently only implemented for KVM_DEV_TYPE_ARM_VGIC_V2.
+ Errors:
+ -ENODEV: Getting or setting this register is not yet supported
+ -EBUSY: One or more VCPUs are running
+
+ KVM_DEV_ARM_VGIC_GRP_NR_IRQS
+ Attributes:
+ A value describing the number of interrupts (SGI, PPI and SPI) for
+ this GIC instance, ranging from 64 to 1024, in increments of 32.
+
+ Errors:
+ -EINVAL: Value set is out of the expected range
+ -EBUSY: Value has already be set, or GIC has already been initialized
+ with default values.
+
+ KVM_DEV_ARM_VGIC_GRP_CTRL
+ Attributes:
+ KVM_DEV_ARM_VGIC_CTRL_INIT
+ request the initialization of the VGIC, no additional parameter in
+ kvm_device_attr.addr.
+ Errors:
+ -ENXIO: VGIC not properly configured as required prior to calling
+ this attribute
+ -ENODEV: no online VCPU
+ -ENOMEM: memory shortage when allocating vgic internal data
diff --git a/kernel/Documentation/virtual/kvm/devices/mpic.txt b/kernel/Documentation/virtual/kvm/devices/mpic.txt
new file mode 100644
index 000000000..8257397ad
--- /dev/null
+++ b/kernel/Documentation/virtual/kvm/devices/mpic.txt
@@ -0,0 +1,53 @@
+MPIC interrupt controller
+=========================
+
+Device types supported:
+ KVM_DEV_TYPE_FSL_MPIC_20 Freescale MPIC v2.0
+ KVM_DEV_TYPE_FSL_MPIC_42 Freescale MPIC v4.2
+
+Only one MPIC instance, of any type, may be instantiated. The created
+MPIC will act as the system interrupt controller, connecting to each
+vcpu's interrupt inputs.
+
+Groups:
+ KVM_DEV_MPIC_GRP_MISC
+ Attributes:
+ KVM_DEV_MPIC_BASE_ADDR (rw, 64-bit)
+ Base address of the 256 KiB MPIC register space. Must be
+ naturally aligned. A value of zero disables the mapping.
+ Reset value is zero.
+
+ KVM_DEV_MPIC_GRP_REGISTER (rw, 32-bit)
+ Access an MPIC register, as if the access were made from the guest.
+ "attr" is the byte offset into the MPIC register space. Accesses
+ must be 4-byte aligned.
+
+ MSIs may be signaled by using this attribute group to write
+ to the relevant MSIIR.
+
+ KVM_DEV_MPIC_GRP_IRQ_ACTIVE (rw, 32-bit)
+ IRQ input line for each standard openpic source. 0 is inactive and 1
+ is active, regardless of interrupt sense.
+
+ For edge-triggered interrupts: Writing 1 is considered an activating
+ edge, and writing 0 is ignored. Reading returns 1 if a previously
+ signaled edge has not been acknowledged, and 0 otherwise.
+
+ "attr" is the IRQ number. IRQ numbers for standard sources are the
+ byte offset of the relevant IVPR from EIVPR0, divided by 32.
+
+IRQ Routing:
+
+ The MPIC emulation supports IRQ routing. Only a single MPIC device can
+ be instantiated. Once that device has been created, it's available as
+ irqchip id 0.
+
+ This irqchip 0 has 256 interrupt pins, which expose the interrupts in
+ the main array of interrupt sources (a.k.a. "SRC" interrupts).
+
+ The numbering is the same as the MPIC device tree binding -- based on
+ the register offset from the beginning of the sources array, without
+ regard to any subdivisions in chip documentation such as "internal"
+ or "external" interrupts.
+
+ Access to non-SRC interrupts is not implemented through IRQ routing mechanisms.
diff --git a/kernel/Documentation/virtual/kvm/devices/s390_flic.txt b/kernel/Documentation/virtual/kvm/devices/s390_flic.txt
new file mode 100644
index 000000000..d1ad9d5ca
--- /dev/null
+++ b/kernel/Documentation/virtual/kvm/devices/s390_flic.txt
@@ -0,0 +1,94 @@
+FLIC (floating interrupt controller)
+====================================
+
+FLIC handles floating (non per-cpu) interrupts, i.e. I/O, service and some
+machine check interruptions. All interrupts are stored in a per-vm list of
+pending interrupts. FLIC performs operations on this list.
+
+Only one FLIC instance may be instantiated.
+
+FLIC provides support to
+- add interrupts (KVM_DEV_FLIC_ENQUEUE)
+- inspect currently pending interrupts (KVM_FLIC_GET_ALL_IRQS)
+- purge all pending floating interrupts (KVM_DEV_FLIC_CLEAR_IRQS)
+- enable/disable for the guest transparent async page faults
+- register and modify adapter interrupt sources (KVM_DEV_FLIC_ADAPTER_*)
+
+Groups:
+ KVM_DEV_FLIC_ENQUEUE
+ Passes a buffer and length into the kernel which are then injected into
+ the list of pending interrupts.
+ attr->addr contains the pointer to the buffer and attr->attr contains
+ the length of the buffer.
+ The format of the data structure kvm_s390_irq as it is copied from userspace
+ is defined in usr/include/linux/kvm.h.
+
+ KVM_DEV_FLIC_GET_ALL_IRQS
+ Copies all floating interrupts into a buffer provided by userspace.
+ When the buffer is too small it returns -ENOMEM, which is the indication
+ for userspace to try again with a bigger buffer.
+ -ENOBUFS is returned when the allocation of a kernelspace buffer has
+ failed.
+ -EFAULT is returned when copying data to userspace failed.
+ All interrupts remain pending, i.e. are not deleted from the list of
+ currently pending interrupts.
+ attr->addr contains the userspace address of the buffer into which all
+ interrupt data will be copied.
+ attr->attr contains the size of the buffer in bytes.
+
+ KVM_DEV_FLIC_CLEAR_IRQS
+ Simply deletes all elements from the list of currently pending floating
+ interrupts. No interrupts are injected into the guest.
+
+ KVM_DEV_FLIC_APF_ENABLE
+ Enables async page faults for the guest. So in case of a major page fault
+ the host is allowed to handle this async and continues the guest.
+
+ KVM_DEV_FLIC_APF_DISABLE_WAIT
+ Disables async page faults for the guest and waits until already pending
+ async page faults are done. This is necessary to trigger a completion interrupt
+ for every init interrupt before migrating the interrupt list.
+
+ KVM_DEV_FLIC_ADAPTER_REGISTER
+ Register an I/O adapter interrupt source. Takes a kvm_s390_io_adapter
+ describing the adapter to register:
+
+struct kvm_s390_io_adapter {
+ __u32 id;
+ __u8 isc;
+ __u8 maskable;
+ __u8 swap;
+ __u8 pad;
+};
+
+ id contains the unique id for the adapter, isc the I/O interruption subclass
+ to use, maskable whether this adapter may be masked (interrupts turned off)
+ and swap whether the indicators need to be byte swapped.
+
+
+ KVM_DEV_FLIC_ADAPTER_MODIFY
+ Modifies attributes of an existing I/O adapter interrupt source. Takes
+ a kvm_s390_io_adapter_req specifiying the adapter and the operation:
+
+struct kvm_s390_io_adapter_req {
+ __u32 id;
+ __u8 type;
+ __u8 mask;
+ __u16 pad0;
+ __u64 addr;
+};
+
+ id specifies the adapter and type the operation. The supported operations
+ are:
+
+ KVM_S390_IO_ADAPTER_MASK
+ mask or unmask the adapter, as specified in mask
+
+ KVM_S390_IO_ADAPTER_MAP
+ perform a gmap translation for the guest address provided in addr,
+ pin a userspace page for the translated address and add it to the
+ list of mappings
+
+ KVM_S390_IO_ADAPTER_UNMAP
+ release a userspace page for the translated address specified in addr
+ from the list of mappings
diff --git a/kernel/Documentation/virtual/kvm/devices/vfio.txt b/kernel/Documentation/virtual/kvm/devices/vfio.txt
new file mode 100644
index 000000000..ef51740c6
--- /dev/null
+++ b/kernel/Documentation/virtual/kvm/devices/vfio.txt
@@ -0,0 +1,22 @@
+VFIO virtual device
+===================
+
+Device types supported:
+ KVM_DEV_TYPE_VFIO
+
+Only one VFIO instance may be created per VM. The created device
+tracks VFIO groups in use by the VM and features of those groups
+important to the correctness and acceleration of the VM. As groups
+are enabled and disabled for use by the VM, KVM should be updated
+about their presence. When registered with KVM, a reference to the
+VFIO-group is held by KVM.
+
+Groups:
+ KVM_DEV_VFIO_GROUP
+
+KVM_DEV_VFIO_GROUP attributes:
+ KVM_DEV_VFIO_GROUP_ADD: Add a VFIO group to VFIO-KVM device tracking
+ KVM_DEV_VFIO_GROUP_DEL: Remove a VFIO group from VFIO-KVM device tracking
+
+For each, kvm_device_attr.addr points to an int32_t file descriptor
+for the VFIO group.
diff --git a/kernel/Documentation/virtual/kvm/devices/vm.txt b/kernel/Documentation/virtual/kvm/devices/vm.txt
new file mode 100644
index 000000000..5542c4641
--- /dev/null
+++ b/kernel/Documentation/virtual/kvm/devices/vm.txt
@@ -0,0 +1,85 @@
+Generic vm interface
+====================================
+
+The virtual machine "device" also accepts the ioctls KVM_SET_DEVICE_ATTR,
+KVM_GET_DEVICE_ATTR, and KVM_HAS_DEVICE_ATTR. The interface uses the same
+struct kvm_device_attr as other devices, but targets VM-wide settings
+and controls.
+
+The groups and attributes per virtual machine, if any, are architecture
+specific.
+
+1. GROUP: KVM_S390_VM_MEM_CTRL
+Architectures: s390
+
+1.1. ATTRIBUTE: KVM_S390_VM_MEM_ENABLE_CMMA
+Parameters: none
+Returns: -EBUSY if a vcpu is already defined, otherwise 0
+
+Enables Collaborative Memory Management Assist (CMMA) for the virtual machine.
+
+1.2. ATTRIBUTE: KVM_S390_VM_MEM_CLR_CMMA
+Parameters: none
+Returns: 0
+
+Clear the CMMA status for all guest pages, so any pages the guest marked
+as unused are again used any may not be reclaimed by the host.
+
+1.3. ATTRIBUTE KVM_S390_VM_MEM_LIMIT_SIZE
+Parameters: in attr->addr the address for the new limit of guest memory
+Returns: -EFAULT if the given address is not accessible
+ -EINVAL if the virtual machine is of type UCONTROL
+ -E2BIG if the given guest memory is to big for that machine
+ -EBUSY if a vcpu is already defined
+ -ENOMEM if not enough memory is available for a new shadow guest mapping
+ 0 otherwise
+
+Allows userspace to query the actual limit and set a new limit for
+the maximum guest memory size. The limit will be rounded up to
+2048 MB, 4096 GB, 8192 TB respectively, as this limit is governed by
+the number of page table levels.
+
+2. GROUP: KVM_S390_VM_CPU_MODEL
+Architectures: s390
+
+2.1. ATTRIBUTE: KVM_S390_VM_CPU_MACHINE (r/o)
+
+Allows user space to retrieve machine and kvm specific cpu related information:
+
+struct kvm_s390_vm_cpu_machine {
+ __u64 cpuid; # CPUID of host
+ __u32 ibc; # IBC level range offered by host
+ __u8 pad[4];
+ __u64 fac_mask[256]; # set of cpu facilities enabled by KVM
+ __u64 fac_list[256]; # set of cpu facilities offered by host
+}
+
+Parameters: address of buffer to store the machine related cpu data
+ of type struct kvm_s390_vm_cpu_machine*
+Returns: -EFAULT if the given address is not accessible from kernel space
+ -ENOMEM if not enough memory is available to process the ioctl
+ 0 in case of success
+
+2.2. ATTRIBUTE: KVM_S390_VM_CPU_PROCESSOR (r/w)
+
+Allows user space to retrieve or request to change cpu related information for a vcpu:
+
+struct kvm_s390_vm_cpu_processor {
+ __u64 cpuid; # CPUID currently (to be) used by this vcpu
+ __u16 ibc; # IBC level currently (to be) used by this vcpu
+ __u8 pad[6];
+ __u64 fac_list[256]; # set of cpu facilities currently (to be) used
+ # by this vcpu
+}
+
+KVM does not enforce or limit the cpu model data in any form. Take the information
+retrieved by means of KVM_S390_VM_CPU_MACHINE as hint for reasonable configuration
+setups. Instruction interceptions triggered by additionally set facilitiy bits that
+are not handled by KVM need to by imlemented in the VM driver code.
+
+Parameters: address of buffer to store/set the processor related cpu
+ data of type struct kvm_s390_vm_cpu_processor*.
+Returns: -EBUSY in case 1 or more vcpus are already activated (only in write case)
+ -EFAULT if the given address is not accessible from kernel space
+ -ENOMEM if not enough memory is available to process the ioctl
+ 0 in case of success
diff --git a/kernel/Documentation/virtual/kvm/devices/xics.txt b/kernel/Documentation/virtual/kvm/devices/xics.txt
new file mode 100644
index 000000000..42864935a
--- /dev/null
+++ b/kernel/Documentation/virtual/kvm/devices/xics.txt
@@ -0,0 +1,66 @@
+XICS interrupt controller
+
+Device type supported: KVM_DEV_TYPE_XICS
+
+Groups:
+ KVM_DEV_XICS_SOURCES
+ Attributes: One per interrupt source, indexed by the source number.
+
+This device emulates the XICS (eXternal Interrupt Controller
+Specification) defined in PAPR. The XICS has a set of interrupt
+sources, each identified by a 20-bit source number, and a set of
+Interrupt Control Presentation (ICP) entities, also called "servers",
+each associated with a virtual CPU.
+
+The ICP entities are created by enabling the KVM_CAP_IRQ_ARCH
+capability for each vcpu, specifying KVM_CAP_IRQ_XICS in args[0] and
+the interrupt server number (i.e. the vcpu number from the XICS's
+point of view) in args[1] of the kvm_enable_cap struct. Each ICP has
+64 bits of state which can be read and written using the
+KVM_GET_ONE_REG and KVM_SET_ONE_REG ioctls on the vcpu. The 64 bit
+state word has the following bitfields, starting at the
+least-significant end of the word:
+
+* Unused, 16 bits
+
+* Pending interrupt priority, 8 bits
+ Zero is the highest priority, 255 means no interrupt is pending.
+
+* Pending IPI (inter-processor interrupt) priority, 8 bits
+ Zero is the highest priority, 255 means no IPI is pending.
+
+* Pending interrupt source number, 24 bits
+ Zero means no interrupt pending, 2 means an IPI is pending
+
+* Current processor priority, 8 bits
+ Zero is the highest priority, meaning no interrupts can be
+ delivered, and 255 is the lowest priority.
+
+Each source has 64 bits of state that can be read and written using
+the KVM_GET_DEVICE_ATTR and KVM_SET_DEVICE_ATTR ioctls, specifying the
+KVM_DEV_XICS_SOURCES attribute group, with the attribute number being
+the interrupt source number. The 64 bit state word has the following
+bitfields, starting from the least-significant end of the word:
+
+* Destination (server number), 32 bits
+ This specifies where the interrupt should be sent, and is the
+ interrupt server number specified for the destination vcpu.
+
+* Priority, 8 bits
+ This is the priority specified for this interrupt source, where 0 is
+ the highest priority and 255 is the lowest. An interrupt with a
+ priority of 255 will never be delivered.
+
+* Level sensitive flag, 1 bit
+ This bit is 1 for a level-sensitive interrupt source, or 0 for
+ edge-sensitive (or MSI).
+
+* Masked flag, 1 bit
+ This bit is set to 1 if the interrupt is masked (cannot be delivered
+ regardless of its priority), for example by the ibm,int-off RTAS
+ call, or 0 if it is not masked.
+
+* Pending flag, 1 bit
+ This bit is 1 if the source has a pending interrupt, otherwise 0.
+
+Only one XICS instance may be created per VM.