dragonball: add set_vm_configuration api

Set virtual machine configuration configurations.

Signed-off-by: wllenyj <wllenyj@linux.alibaba.com>

src/dragonball/src/api/v1/machine_config.rs

@@ -0,0 +1,86 @@
+// Copyright (C) 2022 Alibaba Cloud. All rights reserved.
+// Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+/// We only support this number of vcpus for now. Mostly because we have set all vcpu related metrics as u8
+/// and breaking u8 will take extra efforts.
+pub const MAX_SUPPORTED_VCPUS: u8 = 254;
+
+/// Memory hotplug value should have alignment in this size (unit: MiB)
+pub const MEMORY_HOTPLUG_ALIGHMENT: u8 = 64;
+
+/// Errors associated with configuring the microVM.
+#[derive(Debug, PartialEq, thiserror::Error)]
+pub enum VmConfigError {
+    /// Cannot update the configuration of the microvm post boot.
+    #[error("update operation is not allowed after boot")]
+    UpdateNotAllowedPostBoot,
+
+    /// The max vcpu count is invalid.
+    #[error("the vCPU number shouldn't large than {}", MAX_SUPPORTED_VCPUS)]
+    VcpuCountExceedsMaximum,
+
+    /// The vcpu count is invalid. When hyperthreading is enabled, the `cpu_count` must be either
+    /// 1 or an even number.
+    #[error(
+        "the vCPU number '{0}' can only be 1 or an even number when hyperthreading is enabled"
+    )]
+    InvalidVcpuCount(u8),
+
+    /// The threads_per_core is invalid. It should be either 1 or 2.
+    #[error("the threads_per_core number '{0}' can only be 1 or 2")]
+    InvalidThreadsPerCore(u8),
+
+    /// The cores_per_die is invalid. It should be larger than 0.
+    #[error("the cores_per_die number '{0}' can only be larger than 0")]
+    InvalidCoresPerDie(u8),
+
+    /// The dies_per_socket is invalid. It should be larger than 0.
+    #[error("the dies_per_socket number '{0}' can only be larger than 0")]
+    InvalidDiesPerSocket(u8),
+
+    /// The socket number is invalid. It should be either 1 or 2.
+    #[error("the socket number '{0}' can only be 1 or 2")]
+    InvalidSocket(u8),
+
+    /// max vcpu count inferred from cpu topology(threads_per_core * cores_per_die * dies_per_socket * sockets) should be larger or equal to vcpu_count
+    #[error("the max vcpu count inferred from cpu topology '{0}' (threads_per_core * cores_per_die * dies_per_socket * sockets) should be larger or equal to vcpu_count")]
+    InvalidCpuTopology(u8),
+
+    /// The max vcpu count is invalid.
+    #[error(
+        "the max vCPU number '{0}' shouldn't less than vCPU count and can only be 1 or an even number when hyperthreading is enabled"
+    )]
+    InvalidMaxVcpuCount(u8),
+
+    /// The memory size is invalid. The memory can only be an unsigned integer.
+    #[error("the memory size 0x{0:x}MiB is invalid")]
+    InvalidMemorySize(usize),
+
+    /// The hotplug memory size is invalid. The memory can only be an unsigned integer.
+    #[error(
+        "the hotplug memory size '{0}' (MiB) is invalid, must be multiple of {}",
+        MEMORY_HOTPLUG_ALIGHMENT
+    )]
+    InvalidHotplugMemorySize(usize),
+
+    /// The memory type is invalid.
+    #[error("the memory type '{0}' is invalid")]
+    InvalidMemType(String),
+
+    /// The memory file path is invalid.
+    #[error("the memory file path is invalid")]
+    InvalidMemFilePath(String),
+
+    /// NUMA region memory size is invalid
+    #[error("Total size of memory in NUMA regions: {0}, should matches memory size in config")]
+    InvalidNumaRegionMemorySize(usize),
+
+    /// NUMA region vCPU count is invalid
+    #[error("Total counts of vCPUs in NUMA regions: {0}, should matches max vcpu count in config")]
+    InvalidNumaRegionCpuCount(u16),
+
+    /// NUMA region vCPU count is invalid
+    #[error("Max id of vCPUs in NUMA regions: {0}, should matches max vcpu count in config")]
+    InvalidNumaRegionCpuMaxId(u16),
+}

src/dragonball/src/api/v1/mod.rs

@@ -15,3 +15,7 @@ pub use self::boot_source::{BootSourceConfig, BootSourceConfigError, DEFAULT_KER
 /// Wrapper over the microVM general information.
 mod instance_info;
 pub use self::instance_info::{InstanceInfo, InstanceState};
+
+/// Wrapper for configuring the memory and CPU of the microVM.
+mod machine_config;
+pub use self::machine_config::{VmConfigError, MAX_SUPPORTED_VCPUS};

src/dragonball/src/api/v1/vmm_action.rs

@@ -9,12 +9,12 @@
 use std::fs::File;
 use std::sync::mpsc::{Receiver, Sender, TryRecvError};
 
-use log::{debug, error, warn};
+use log::{debug, error, info, warn};
 use vmm_sys_util::eventfd::EventFd;
 
 use crate::error::{Result, StartMicrovmError, StopMicrovmError};
 use crate::event_manager::EventManager;
-use crate::vm::{KernelConfigInfo, VmConfigInfo};
+use crate::vm::{CpuTopology, KernelConfigInfo, VmConfigInfo};
 use crate::vmm::Vmm;
 
 use super::*;
@@ -38,6 +38,11 @@ pub enum VmmActionError {
     /// The action `StopMicroVm` failed either because of bad user input or an internal error.
     #[error("failed to shutdown the VM: {0}")]
     StopMicrovm(#[source] StopMicrovmError),
+
+    /// One of the actions `GetVmConfiguration` or `SetVmConfiguration` failed either because of bad
+    /// input or an internal error.
+    #[error("failed to set configuration for the VM: {0}")]
+    MachineConfig(#[source] VmConfigError),
 }
 
 /// This enum represents the public interface of the VMM. Each action contains various
@@ -55,6 +60,13 @@ pub enum VmmAction {
     /// When vmm is used as the crate by the other process, which is need to
     /// shutdown the vcpu threads and destory all of the object.
     ShutdownMicroVm,
+
+    /// Get the configuration of the microVM.
+    GetVmConfiguration,
+
+    /// Set the microVM configuration (memory & vcpu) using `VmConfig` as input. This
+    /// action can only be called before the microVM has booted.
+    SetVmConfiguration(VmConfigInfo),
 }
 
 /// The enum represents the response sent by the VMM in case of success. The response is either
@@ -63,6 +75,8 @@ pub enum VmmAction {
 pub enum VmmData {
     /// No data is sent on the channel.
     Empty,
+    /// The microVM configuration represented by `VmConfigInfo`.
+    MachineConfiguration(Box<VmConfigInfo>),
 }
 
 /// Request data type used to communicate between the API and the VMM.
@@ -114,6 +128,12 @@ impl VmmService {
             }
             VmmAction::StartMicroVm => self.start_microvm(vmm, event_mgr),
             VmmAction::ShutdownMicroVm => self.shutdown_microvm(vmm),
+            VmmAction::GetVmConfiguration => Ok(VmmData::MachineConfiguration(Box::new(
+                self.machine_config.clone(),
+            ))),
+            VmmAction::SetVmConfiguration(machine_config) => {
+                self.set_vm_configuration(vmm, machine_config)
+            }
         };
 
         debug!("send vmm response: {:?}", response);
@@ -193,4 +213,134 @@ impl VmmService {
 
         Ok(VmmData::Empty)
     }
+
+    /// Set virtual machine configuration configurations.
+    pub fn set_vm_configuration(
+        &mut self,
+        vmm: &mut Vmm,
+        machine_config: VmConfigInfo,
+    ) -> VmmRequestResult {
+        use self::VmConfigError::*;
+        use self::VmmActionError::MachineConfig;
+
+        let vm = vmm
+            .get_vm_by_id_mut("")
+            .ok_or(VmmActionError::InvalidVMID)?;
+        if vm.is_vm_initialized() {
+            return Err(MachineConfig(UpdateNotAllowedPostBoot));
+        }
+
+        // If the check is successful, set it up together.
+        let mut config = vm.vm_config().clone();
+        if config.vcpu_count != machine_config.vcpu_count {
+            let vcpu_count = machine_config.vcpu_count;
+            // Check that the vcpu_count value is >=1.
+            if vcpu_count == 0 {
+                return Err(MachineConfig(InvalidVcpuCount(vcpu_count)));
+            }
+            config.vcpu_count = vcpu_count;
+        }
+
+        if config.cpu_topology != machine_config.cpu_topology {
+            let cpu_topology = &machine_config.cpu_topology;
+            // Check if dies_per_socket, cores_per_die, threads_per_core and socket number is valid
+            if cpu_topology.threads_per_core < 1 || cpu_topology.threads_per_core > 2 {
+                return Err(MachineConfig(InvalidThreadsPerCore(
+                    cpu_topology.threads_per_core,
+                )));
+            }
+            let vcpu_count_from_topo = cpu_topology
+                .sockets
+                .checked_mul(cpu_topology.dies_per_socket)
+                .ok_or(MachineConfig(VcpuCountExceedsMaximum))?
+                .checked_mul(cpu_topology.cores_per_die)
+                .ok_or(MachineConfig(VcpuCountExceedsMaximum))?
+                .checked_mul(cpu_topology.threads_per_core)
+                .ok_or(MachineConfig(VcpuCountExceedsMaximum))?;
+            if vcpu_count_from_topo > MAX_SUPPORTED_VCPUS {
+                return Err(MachineConfig(VcpuCountExceedsMaximum));
+            }
+            if vcpu_count_from_topo < config.vcpu_count {
+                return Err(MachineConfig(InvalidCpuTopology(vcpu_count_from_topo)));
+            }
+            config.cpu_topology = cpu_topology.clone();
+        } else {
+            // the same default
+            let mut default_cpu_topology = CpuTopology {
+                threads_per_core: 1,
+                cores_per_die: config.vcpu_count,
+                dies_per_socket: 1,
+                sockets: 1,
+            };
+            if machine_config.max_vcpu_count > config.vcpu_count {
+                default_cpu_topology.cores_per_die = machine_config.max_vcpu_count;
+            }
+            config.cpu_topology = default_cpu_topology;
+        }
+        let cpu_topology = &config.cpu_topology;
+        let max_vcpu_from_topo = cpu_topology.threads_per_core
+            * cpu_topology.cores_per_die
+            * cpu_topology.dies_per_socket
+            * cpu_topology.sockets;
+        // If the max_vcpu_count inferred by cpu_topology is not equal to
+        // max_vcpu_count, max_vcpu_count will be changed. currently, max vcpu size
+        // is used when cpu_topology is not defined and help define the cores_per_die
+        // for the default cpu topology.
+        let mut max_vcpu_count = machine_config.max_vcpu_count;
+        if max_vcpu_count < config.vcpu_count {
+            return Err(MachineConfig(InvalidMaxVcpuCount(max_vcpu_count)));
+        }
+        if max_vcpu_from_topo != max_vcpu_count {
+            max_vcpu_count = max_vcpu_from_topo;
+            info!("Since max_vcpu_count is not equal to cpu topo information, we have changed the max vcpu count to {}", max_vcpu_from_topo);
+        }
+        config.max_vcpu_count = max_vcpu_count;
+
+        config.cpu_pm = machine_config.cpu_pm;
+        config.mem_type = machine_config.mem_type;
+
+        let mem_size_mib_value = machine_config.mem_size_mib;
+        // Support 1TB memory at most, 2MB aligned for huge page.
+        if mem_size_mib_value == 0 || mem_size_mib_value > 0x10_0000 || mem_size_mib_value % 2 != 0
+        {
+            return Err(MachineConfig(InvalidMemorySize(mem_size_mib_value)));
+        }
+        config.mem_size_mib = mem_size_mib_value;
+
+        config.mem_file_path = machine_config.mem_file_path.clone();
+
+        let reserve_memory_bytes = machine_config.reserve_memory_bytes;
+        // Reserved memory must be 2MB aligned and less than half of the total memory.
+        if reserve_memory_bytes % 0x200000 != 0
+            || reserve_memory_bytes > (config.mem_size_mib as u64) << 20
+        {
+            return Err(MachineConfig(InvalidReservedMemorySize(
+                reserve_memory_bytes as usize >> 20,
+            )));
+        }
+        config.reserve_memory_bytes = reserve_memory_bytes;
+        if config.mem_type == "hugetlbfs" && config.mem_file_path.is_empty() {
+            return Err(MachineConfig(InvalidMemFilePath("".to_owned())));
+        }
+        config.vpmu_feature = machine_config.vpmu_feature;
+
+        let vm_id = vm.shared_info().read().unwrap().id.clone();
+        let serial_path = match machine_config.serial_path {
+            Some(value) => value,
+            None => {
+                if config.serial_path.is_none() {
+                    String::from("/run/dragonball/") + &vm_id + "_com1"
+                } else {
+                    // Safe to unwrap() because we have checked it has a value.
+                    config.serial_path.as_ref().unwrap().clone()
+                }
+            }
+        };
+        config.serial_path = Some(serial_path);
+
+        vm.set_vm_config(config.clone());
+        self.machine_config = config;
+
+        Ok(VmmData::Empty)
+    }
 }

src/dragonball/src/vm/mod.rs

@@ -689,7 +689,10 @@ impl Vm {
             .state = InstanceState::Starting;
 
         self.init_guest_memory()?;
-        let vm_as = self.vm_as().cloned().ok_or(StartMicrovmError::AddressManagerError(
+        let vm_as = self
+            .vm_as()
+            .cloned()
+            .ok_or(StartMicrovmError::AddressManagerError(
                 AddressManagerError::GuestMemoryNotInitialized,
             ))?;