History log of /linux-master/include/uapi/linux/acrn.h
Revision Date Author Comments
# 1dbb4f02 16-Nov-2022 Andy Shevchenko <andriy.shevchenko@linux.intel.com>

virt: acrn: Mark the uuid field as unused

After the commits for userspace (see Link tags below) the uuid field
is not being used in the ACRN code. Update kernel to reflect these
changes, i.e. do the following:
- adding a comment explaining that it's not used anymore
- replacing the specific type by a raw buffer
- updating the example code accordingly

The advertised field confused users and actually never been used.
So the wrong part here is that kernel puts something which userspace
never used and hence this may confuse a reader of this code.

Note, that there is only a single tool that had been prepared a year
ago for these forthcoming changes in the kernel.

Link: https://github.com/projectacrn/acrn-hypervisor/commit/da0d24326ed6
Link: https://github.com/projectacrn/acrn-hypervisor/commit/bb0327e70097
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20221116162956.72658-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# 424f1ac2 23-Sep-2021 Shuo Liu <shuo.a.liu@intel.com>

virt: acrn: Introduce interfaces for virtual device creating/destroying

The ACRN hypervisor can emulate a virtual device within hypervisor for a
Guest VM. The emulated virtual device can work without the ACRN
userspace after creation. The hypervisor do the emulation of that device.

To support the virtual device creating/destroying, HSM provides the
following ioctls:
- ACRN_IOCTL_CREATE_VDEV
Pass data struct acrn_vdev from userspace to the hypervisor, and inform
the hypervisor to create a virtual device for a User VM.
- ACRN_IOCTL_DESTROY_VDEV
Pass data struct acrn_vdev from userspace to the hypervisor, and inform
the hypervisor to destroy a virtual device of a User VM.

These new APIs will be used by user space code vm_add_hv_vdev and
vm_remove_hv_vdev in
https://github.com/projectacrn/acrn-hypervisor/blob/master/devicemodel/core/vmmapi.c

Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Signed-off-by: Fei Li <fei1.li@intel.com>
Link: https://lore.kernel.org/r/20210923084128.18902-3-fei1.li@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# 29a9f275 23-Sep-2021 Shuo Liu <shuo.a.liu@intel.com>

virt: acrn: Introduce interfaces for MMIO device passthrough

MMIO device passthrough enables an OS in a virtual machine to directly
access a MMIO device in the host. It promises almost the native
performance, which is required in performance-critical scenarios of
ACRN.

HSM provides the following ioctls:
- Assign - ACRN_IOCTL_ASSIGN_MMIODEV
Pass data struct acrn_mmiodev from userspace to the hypervisor, and
inform the hypervisor to assign a MMIO device to a User VM.

- De-assign - ACRN_IOCTL_DEASSIGN_PCIDEV
Pass data struct acrn_mmiodev from userspace to the hypervisor, and
inform the hypervisor to de-assign a MMIO device from a User VM.

These new APIs will be used by user space code vm_assign_mmiodev and
vm_deassign_mmiodev in
https://github.com/projectacrn/acrn-hypervisor/blob/master/devicemodel/core/vmmapi.c

Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Signed-off-by: Fei Li <fei1.li@intel.com>
Link: https://lore.kernel.org/r/20210923084128.18902-2-fei1.li@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# aa3b483f 06-Feb-2021 Shuo Liu <shuo.a.liu@intel.com>

virt: acrn: Introduce irqfd

irqfd is a mechanism to inject a specific interrupt to a User VM using a
decoupled eventfd mechanism.

Vhost is a kernel-level virtio server which uses eventfd for interrupt
injection. To support vhost on ACRN, irqfd is introduced in HSM.

HSM provides ioctls to associate a virtual Message Signaled Interrupt
(MSI) with an eventfd. The corresponding virtual MSI will be injected
into a User VM once the eventfd got signal.

Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-17-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# d8ad5151 06-Feb-2021 Shuo Liu <shuo.a.liu@intel.com>

virt: acrn: Introduce ioeventfd

ioeventfd is a mechanism to register PIO/MMIO regions to trigger an
eventfd signal when written to by a User VM. ACRN userspace can register
any arbitrary I/O address with a corresponding eventfd and then pass the
eventfd to a specific end-point of interest for handling.

Vhost is a kernel-level virtio server which uses eventfd for signalling.
To support vhost on ACRN, ioeventfd is introduced in HSM.

A new I/O client dedicated to ioeventfd is associated with a User VM
during VM creation. HSM provides ioctls to associate an I/O region with
a eventfd. The I/O client signals a eventfd once its corresponding I/O
region is matched with an I/O request.

Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-16-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# 3d679d5a 06-Feb-2021 Shuo Liu <shuo.a.liu@intel.com>

virt: acrn: Introduce interfaces to query C-states and P-states allowed by hypervisor

The C-states and P-states data are used to support CPU power management.
The hypervisor controls C-states and P-states for a User VM.

ACRN userspace need to query the data from the hypervisor to build ACPI
tables for a User VM.

HSM provides ioctls for ACRN userspace to query C-states and P-states
data obtained from the hypervisor.

Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-14-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# c7cf8d27 06-Feb-2021 Shuo Liu <shuo.a.liu@intel.com>

virt: acrn: Introduce interrupt injection interfaces

ACRN userspace need to inject virtual interrupts into a User VM in
devices emulation.

HSM needs provide interfaces to do so.

Introduce following interrupt injection interfaces:

ioctl ACRN_IOCTL_SET_IRQLINE:
Pass data from userspace to the hypervisor, and inform the hypervisor
to inject a virtual IOAPIC GSI interrupt to a User VM.

ioctl ACRN_IOCTL_INJECT_MSI:
Pass data struct acrn_msi_entry from userspace to the hypervisor, and
inform the hypervisor to inject a virtual MSI to a User VM.

ioctl ACRN_IOCTL_VM_INTR_MONITOR:
Set a 4-Kbyte aligned shared page for statistics information of
interrupts of a User VM.

Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-13-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# ce011e13 06-Feb-2021 Shuo Liu <shuo.a.liu@intel.com>

virt: acrn: Introduce interfaces for PCI device passthrough

PCI device passthrough enables an OS in a virtual machine to directly
access a PCI device in the host. It promises almost the native
performance, which is required in performance-critical scenarios of
ACRN.

HSM provides the following ioctls:
- Assign - ACRN_IOCTL_ASSIGN_PCIDEV
Pass data struct acrn_pcidev from userspace to the hypervisor, and
inform the hypervisor to assign a PCI device to a User VM.

- De-assign - ACRN_IOCTL_DEASSIGN_PCIDEV
Pass data struct acrn_pcidev from userspace to the hypervisor, and
inform the hypervisor to de-assign a PCI device from a User VM.

- Set a interrupt of a passthrough device - ACRN_IOCTL_SET_PTDEV_INTR
Pass data struct acrn_ptdev_irq from userspace to the hypervisor,
and inform the hypervisor to map a INTx interrupt of passthrough
device of User VM.

- Reset passthrough device interrupt - ACRN_IOCTL_RESET_PTDEV_INTR
Pass data struct acrn_ptdev_irq from userspace to the hypervisor,
and inform the hypervisor to unmap a INTx interrupt of passthrough
device of User VM.

Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-12-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# 3c4c3316 06-Feb-2021 Shuo Liu <shuo.a.liu@intel.com>

virt: acrn: Introduce PCI configuration space PIO accesses combiner

A User VM can access its virtual PCI configuration spaces via port IO
approach, which has two following steps:
1) writes address into port 0xCF8
2) put/get data in/from port 0xCFC

To distribute a complete PCI configuration space access one time, HSM
need to combine such two accesses together.

Combine two paired PIO I/O requests into one PCI I/O request and
continue the I/O request distribution.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-11-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# 72f293de 06-Feb-2021 Shuo Liu <shuo.a.liu@intel.com>

virt: acrn: Introduce I/O request management

An I/O request of a User VM, which is constructed by the hypervisor, is
distributed by the ACRN Hypervisor Service Module to an I/O client
corresponding to the address range of the I/O request.

For each User VM, there is a shared 4-KByte memory region used for I/O
requests communication between the hypervisor and Service VM. An I/O
request is a 256-byte structure buffer, which is 'struct
acrn_io_request', that is filled by an I/O handler of the hypervisor
when a trapped I/O access happens in a User VM. ACRN userspace in the
Service VM first allocates a 4-KByte page and passes the GPA (Guest
Physical Address) of the buffer to the hypervisor. The buffer is used as
an array of 16 I/O request slots with each I/O request slot being 256
bytes. This array is indexed by vCPU ID.

An I/O client, which is 'struct acrn_ioreq_client', is responsible for
handling User VM I/O requests whose accessed GPA falls in a certain
range. Multiple I/O clients can be associated with each User VM. There
is a special client associated with each User VM, called the default
client, that handles all I/O requests that do not fit into the range of
any other I/O clients. The ACRN userspace acts as the default client for
each User VM.

The state transitions of a ACRN I/O request are as follows.

FREE -> PENDING -> PROCESSING -> COMPLETE -> FREE -> ...

FREE: this I/O request slot is empty
PENDING: a valid I/O request is pending in this slot
PROCESSING: the I/O request is being processed
COMPLETE: the I/O request has been processed

An I/O request in COMPLETE or FREE state is owned by the hypervisor. HSM
and ACRN userspace are in charge of processing the others.

The processing flow of I/O requests are listed as following:

a) The I/O handler of the hypervisor will fill an I/O request with
PENDING state when a trapped I/O access happens in a User VM.
b) The hypervisor makes an upcall, which is a notification interrupt, to
the Service VM.
c) The upcall handler schedules a worker to dispatch I/O requests.
d) The worker looks for the PENDING I/O requests, assigns them to
different registered clients based on the address of the I/O accesses,
updates their state to PROCESSING, and notifies the corresponding
client to handle.
e) The notified client handles the assigned I/O requests.
f) The HSM updates I/O requests states to COMPLETE and notifies the
hypervisor of the completion via hypercalls.

Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Acked-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-10-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# 88f537d5 06-Feb-2021 Shuo Liu <shuo.a.liu@intel.com>

virt: acrn: Introduce EPT mapping management

The HSM provides hypervisor services to the ACRN userspace. While
launching a User VM, ACRN userspace needs to allocate memory and request
the ACRN Hypervisor to set up the EPT mapping for the VM.

A mapping cache is introduced for accelerating the translation between
the Service VM kernel virtual address and User VM physical address.

>From the perspective of the hypervisor, the types of GPA of User VM can be
listed as following:
1) RAM region, which is used by User VM as system ram.
2) MMIO region, which is recognized by User VM as MMIO. MMIO region is
used to be utilized for devices emulation.

Generally, User VM RAM regions mapping is set up before VM started and
is released in the User VM destruction. MMIO regions mapping may be set
and unset dynamically during User VM running.

To achieve this, ioctls ACRN_IOCTL_SET_MEMSEG and ACRN_IOCTL_UNSET_MEMSEG
are introduced in HSM.

Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-9-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# 2ad2aaee 06-Feb-2021 Shuo Liu <shuo.a.liu@intel.com>

virt: acrn: Introduce an ioctl to set vCPU registers state

A virtual CPU of User VM has different context due to the different
registers state. ACRN userspace needs to set the virtual CPU
registers state (e.g. giving a initial registers state to a virtual
BSP of a User VM).

HSM provides an ioctl ACRN_IOCTL_SET_VCPU_REGS to do the virtual CPU
registers state setting. The ioctl passes the registers state from ACRN
userspace to the hypervisor directly.

Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-8-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# 9c5137ae 06-Feb-2021 Shuo Liu <shuo.a.liu@intel.com>

virt: acrn: Introduce VM management interfaces

The VM management interfaces expose several VM operations to ACRN
userspace via ioctls. For example, creating VM, starting VM, destroying
VM and so on.

The ACRN Hypervisor needs to exchange data with the ACRN userspace
during the VM operations. HSM provides VM operation ioctls to the ACRN
userspace and communicates with the ACRN Hypervisor for VM operations
via hypercalls.

HSM maintains a list of User VM. Each User VM will be bound to an
existing file descriptor of /dev/acrn_hsm. The User VM will be
destroyed when the file descriptor is closed.

Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-7-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>