feat: add allocator for past 64bit memory region

Virtio-pmem devices need to allocate a memory region in guest physical
memory. The safe place to do this is past 64bit MMIO region.

Signed-off-by: Egor Lazarchuk <[email protected]>

Author: ShadowCurse

src/vmm/src/arch/aarch64/layout.rs

@@ -139,3 +139,5 @@ pub const MEM_64BIT_DEVICES_START: u64 = MMIO64_MEM_START;
 pub const MEM_64BIT_DEVICES_SIZE: u64 = MMIO64_MEM_SIZE;
 /// First address past the 64-bit MMIO gap
 pub const FIRST_ADDR_PAST_64BITS_MMIO: u64 = MMIO64_MEM_START + MMIO64_MEM_SIZE;
+/// Size of the memory past 64-bit MMIO gap
+pub const PAST_64BITS_MMIO_SIZE: u64 = 512 << 30;

src/vmm/src/arch/mod.rs

@@ -21,14 +21,7 @@ pub use aarch64::vm::{ArchVm, ArchVmError, VmState};
 #[cfg(target_arch = "aarch64")]
 pub use aarch64::{
     ConfigurationError, arch_memory_regions, configure_system_for_boot, get_kernel_start,
-    initrd_load_addr, layout::BOOT_DEVICE_MEM_START, layout::CMDLINE_MAX_SIZE,
-    layout::GSI_LEGACY_END, layout::GSI_LEGACY_NUM, layout::GSI_LEGACY_START, layout::GSI_MSI_END,
-    layout::GSI_MSI_NUM, layout::GSI_MSI_START, layout::MEM_32BIT_DEVICES_SIZE,
-    layout::MEM_32BIT_DEVICES_START, layout::MEM_64BIT_DEVICES_SIZE,
-    layout::MEM_64BIT_DEVICES_START, layout::MMIO32_MEM_SIZE, layout::MMIO32_MEM_START,
-    layout::PCI_MMCONFIG_SIZE, layout::PCI_MMCONFIG_START,
-    layout::PCI_MMIO_CONFIG_SIZE_PER_SEGMENT, layout::RTC_MEM_START, layout::SERIAL_MEM_START,
-    layout::SPI_START, layout::SYSTEM_MEM_SIZE, layout::SYSTEM_MEM_START, load_kernel,
+    initrd_load_addr, layout::*, load_kernel,
 };
 
 /// Module for x86_64 related functionality.
@@ -45,14 +38,7 @@ pub use x86_64::vm::{ArchVm, ArchVmError, VmState};
 #[cfg(target_arch = "x86_64")]
 pub use crate::arch::x86_64::{
     ConfigurationError, arch_memory_regions, configure_system_for_boot, get_kernel_start,
-    initrd_load_addr, layout::APIC_ADDR, layout::BOOT_DEVICE_MEM_START, layout::CMDLINE_MAX_SIZE,
-    layout::GSI_LEGACY_END, layout::GSI_LEGACY_NUM, layout::GSI_LEGACY_START, layout::GSI_MSI_END,
-    layout::GSI_MSI_NUM, layout::GSI_MSI_START, layout::IOAPIC_ADDR,
-    layout::MEM_32BIT_DEVICES_SIZE, layout::MEM_32BIT_DEVICES_START,
-    layout::MEM_64BIT_DEVICES_SIZE, layout::MEM_64BIT_DEVICES_START, layout::MMIO32_MEM_SIZE,
-    layout::MMIO32_MEM_START, layout::PCI_MMCONFIG_SIZE, layout::PCI_MMCONFIG_START,
-    layout::PCI_MMIO_CONFIG_SIZE_PER_SEGMENT, layout::SYSTEM_MEM_SIZE, layout::SYSTEM_MEM_START,
-    load_kernel,
+    initrd_load_addr, layout::*, load_kernel,
 };
 
 /// Types of devices that can get attached to this platform.

src/vmm/src/arch/x86_64/layout.rs

@@ -132,3 +132,5 @@ pub const MEM_64BIT_DEVICES_START: u64 = MMIO64_MEM_START;
 pub const MEM_64BIT_DEVICES_SIZE: u64 = MMIO64_MEM_SIZE;
 /// First address past the 64-bit MMIO gap
 pub const FIRST_ADDR_PAST_64BITS_MMIO: u64 = MMIO64_MEM_START + MMIO64_MEM_SIZE;
+/// Size of the memory past 64-bit MMIO gap
+pub const PAST_64BITS_MMIO_SIZE: u64 = 512 << 30;

src/vmm/src/vstate/resources.rs

@@ -50,6 +50,8 @@ pub struct ResourceAllocator {
     pub mmio32_memory: AddressAllocator,
     /// Allocator for memory in the 64-bit MMIO address space
     pub mmio64_memory: AddressAllocator,
+    /// Allocator for memory after the 64-bit MMIO address space
+    pub past_mmio64_memory: AddressAllocator,
     /// Memory allocator for system data
     pub system_memory: AddressAllocator,
 }
@@ -79,6 +81,11 @@ impl ResourceAllocator {
                 arch::MEM_64BIT_DEVICES_SIZE,
             )
             .unwrap(),
+            past_mmio64_memory: AddressAllocator::new(
+                arch::FIRST_ADDR_PAST_64BITS_MMIO,
+                arch::PAST_64BITS_MMIO_SIZE,
+            )
+            .unwrap(),
             system_memory: AddressAllocator::new(arch::SYSTEM_MEM_START, arch::SYSTEM_MEM_SIZE)
                 .unwrap(),
         }