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authorLinus Torvalds <torvalds@linux-foundation.org>2017-05-10 11:29:23 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-05-10 11:29:23 -0700
commit5ccd414080822d5257c3569f4aeca74f63f4a257 (patch)
tree4b567bfc0a8b29dbac9712821062b28337eb3408 /Documentation
parent29250d301b0c75ef142b51eebee6b7403cc79624 (diff)
parent36c344f3f1ffc0b1b20abd237b7401dc6687ee8f (diff)
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull more KVM updates from Paolo Bonzini: "ARM: - bugfixes - moved shared 32-bit/64-bit files to virt/kvm/arm - support for saving/restoring virtual ITS state to userspace PPC: - XIVE (eXternal Interrupt Virtualization Engine) support x86: - nVMX improvements, including emulated page modification logging (PML) which brings nice performance improvements on some workloads" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (45 commits) KVM: arm/arm64: vgic-its: Cleanup after failed ITT restore KVM: arm/arm64: Don't call map_resources when restoring ITS tables KVM: arm/arm64: Register ITS iodev when setting base address KVM: arm/arm64: Get rid of its->initialized field KVM: arm/arm64: Register iodevs when setting redist base and creating VCPUs KVM: arm/arm64: Slightly rework kvm_vgic_addr KVM: arm/arm64: Make vgic_v3_check_base more broadly usable KVM: arm/arm64: Refactor vgic_register_redist_iodevs KVM: Add kvm_vcpu_get_idx to get vcpu index in kvm->vcpus nVMX: Advertise PML to L1 hypervisor nVMX: Implement emulated Page Modification Logging kvm: x86: Add a hook for arch specific dirty logging emulation kvm: nVMX: Validate CR3 target count on nested VM-entry KVM: set no_llseek in stat_fops_per_vm KVM: arm/arm64: vgic: Rename kvm_vgic_vcpu_init to kvm_vgic_vcpu_enable KVM: arm/arm64: Clarification and relaxation to ITS save/restore ABI KVM: arm64: vgic-v3: KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES KVM: arm64: vgic-its: Fix pending table sync KVM: arm64: vgic-its: ITT save and restore KVM: arm64: vgic-its: Device table save/restore ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/virtual/kvm/devices/arm-vgic-its.txt121
-rw-r--r--Documentation/virtual/kvm/devices/arm-vgic-v3.txt6
2 files changed, 127 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/devices/arm-vgic-its.txt b/Documentation/virtual/kvm/devices/arm-vgic-its.txt
index 6081a5b7fc1e..eb06beb75960 100644
--- a/Documentation/virtual/kvm/devices/arm-vgic-its.txt
+++ b/Documentation/virtual/kvm/devices/arm-vgic-its.txt
@@ -32,7 +32,128 @@ Groups:
KVM_DEV_ARM_VGIC_CTRL_INIT
request the initialization of the ITS, no additional parameter in
kvm_device_attr.addr.
+
+ KVM_DEV_ARM_ITS_SAVE_TABLES
+ save the ITS table data into guest RAM, at the location provisioned
+ by the guest in corresponding registers/table entries.
+
+ The layout of the tables in guest memory defines an ABI. The entries
+ are laid out in little endian format as described in the last paragraph.
+
+ KVM_DEV_ARM_ITS_RESTORE_TABLES
+ restore the ITS tables from guest RAM to ITS internal structures.
+
+ The GICV3 must be restored before the ITS and all ITS registers but
+ the GITS_CTLR must be restored before restoring the ITS tables.
+
+ The GITS_IIDR read-only register must also be restored before
+ calling KVM_DEV_ARM_ITS_RESTORE_TABLES as the IIDR revision field
+ encodes the ABI revision.
+
+ The expected ordering when restoring the GICv3/ITS is described in section
+ "ITS Restore Sequence".
+
Errors:
-ENXIO: ITS not properly configured as required prior to setting
this attribute
-ENOMEM: Memory shortage when allocating ITS internal data
+ -EINVAL: Inconsistent restored data
+ -EFAULT: Invalid guest ram access
+ -EBUSY: One or more VCPUS are running
+
+ KVM_DEV_ARM_VGIC_GRP_ITS_REGS
+ Attributes:
+ The attr field of kvm_device_attr encodes the offset of the
+ ITS register, relative to the ITS control frame base address
+ (ITS_base).
+
+ kvm_device_attr.addr points to a __u64 value whatever the width
+ of the addressed register (32/64 bits). 64 bit registers can only
+ be accessed with full length.
+
+ Writes to read-only registers are ignored by the kernel except for:
+ - GITS_CREADR. It must be restored otherwise commands in the queue
+ will be re-executed after restoring CWRITER. GITS_CREADR must be
+ restored before restoring the GITS_CTLR which is likely to enable the
+ ITS. Also it must be restored after GITS_CBASER since a write to
+ GITS_CBASER resets GITS_CREADR.
+ - GITS_IIDR. The Revision field encodes the table layout ABI revision.
+ In the future we might implement direct injection of virtual LPIs.
+ This will require an upgrade of the table layout and an evolution of
+ the ABI. GITS_IIDR must be restored before calling
+ KVM_DEV_ARM_ITS_RESTORE_TABLES.
+
+ For other registers, getting or setting a register has the same
+ effect as reading/writing the register on real hardware.
+ Errors:
+ -ENXIO: Offset does not correspond to any supported register
+ -EFAULT: Invalid user pointer for attr->addr
+ -EINVAL: Offset is not 64-bit aligned
+ -EBUSY: one or more VCPUS are running
+
+ ITS Restore Sequence:
+ -------------------------
+
+The following ordering must be followed when restoring the GIC and the ITS:
+a) restore all guest memory and create vcpus
+b) restore all redistributors
+c) provide the its base address
+ (KVM_DEV_ARM_VGIC_GRP_ADDR)
+d) restore the ITS in the following order:
+ 1. Restore GITS_CBASER
+ 2. Restore all other GITS_ registers, except GITS_CTLR!
+ 3. Load the ITS table data (KVM_DEV_ARM_ITS_RESTORE_TABLES)
+ 4. Restore GITS_CTLR
+
+Then vcpus can be started.
+
+ ITS Table ABI REV0:
+ -------------------
+
+ Revision 0 of the ABI only supports the features of a virtual GICv3, and does
+ not support a virtual GICv4 with support for direct injection of virtual
+ interrupts for nested hypervisors.
+
+ The device table and ITT are indexed by the DeviceID and EventID,
+ respectively. The collection table is not indexed by CollectionID, and the
+ entries in the collection are listed in no particular order.
+ All entries are 8 bytes.
+
+ Device Table Entry (DTE):
+
+ bits: | 63| 62 ... 49 | 48 ... 5 | 4 ... 0 |
+ values: | V | next | ITT_addr | Size |
+
+ where;
+ - V indicates whether the entry is valid. If not, other fields
+ are not meaningful.
+ - next: equals to 0 if this entry is the last one; otherwise it
+ corresponds to the DeviceID offset to the next DTE, capped by
+ 2^14 -1.
+ - ITT_addr matches bits [51:8] of the ITT address (256 Byte aligned).
+ - Size specifies the supported number of bits for the EventID,
+ minus one
+
+ Collection Table Entry (CTE):
+
+ bits: | 63| 62 .. 52 | 51 ... 16 | 15 ... 0 |
+ values: | V | RES0 | RDBase | ICID |
+
+ where:
+ - V indicates whether the entry is valid. If not, other fields are
+ not meaningful.
+ - RES0: reserved field with Should-Be-Zero-or-Preserved behavior.
+ - RDBase is the PE number (GICR_TYPER.Processor_Number semantic),
+ - ICID is the collection ID
+
+ Interrupt Translation Entry (ITE):
+
+ bits: | 63 ... 48 | 47 ... 16 | 15 ... 0 |
+ values: | next | pINTID | ICID |
+
+ where:
+ - next: equals to 0 if this entry is the last one; otherwise it corresponds
+ to the EventID offset to the next ITE capped by 2^16 -1.
+ - pINTID is the physical LPI ID; if zero, it means the entry is not valid
+ and other fields are not meaningful.
+ - ICID is the collection ID
diff --git a/Documentation/virtual/kvm/devices/arm-vgic-v3.txt b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
index c1a24612c198..9293b45abdb9 100644
--- a/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
+++ b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
@@ -167,11 +167,17 @@ Groups:
KVM_DEV_ARM_VGIC_CTRL_INIT
request the initialization of the VGIC, no additional parameter in
kvm_device_attr.addr.
+ KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES
+ save all LPI pending bits into guest RAM pending tables.
+
+ The first kB of the pending table is not altered by this operation.
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
+ -EFAULT: Invalid guest ram access
+ -EBUSY: One or more VCPUS are running
KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO