vmm/vstate: guest_memfd, update SET_USER_MEMORY_REGION API

Signed-off-by: Tyler Fanelli <[email protected]>

Author: tylerfanelli

src/vmm/src/linux/vstate.rs

@@ -40,9 +40,12 @@ use kvm_bindings::{
     kvm_clock_data, kvm_debugregs, kvm_irqchip, kvm_lapic_state, kvm_mp_state, kvm_pit_config,
     kvm_pit_state2, kvm_regs, kvm_sregs, kvm_vcpu_events, kvm_xcrs, kvm_xsave, CpuId, MsrList,
     Msrs, KVM_CLOCK_TSC_STABLE, KVM_IRQCHIP_IOAPIC, KVM_IRQCHIP_PIC_MASTER, KVM_IRQCHIP_PIC_SLAVE,
-    KVM_MAX_CPUID_ENTRIES, KVM_PIT_SPEAKER_DUMMY,
+    KVM_MAX_CPUID_ENTRIES, KVM_MEMORY_ATTRIBUTE_PRIVATE, KVM_PIT_SPEAKER_DUMMY,
+};
+use kvm_bindings::{
+    kvm_create_guest_memfd, kvm_memory_attributes, kvm_userspace_memory_region2, KVM_API_VERSION,
+    KVM_MEM_GUEST_MEMFD,
 };
-use kvm_bindings::{kvm_userspace_memory_region, KVM_API_VERSION};
 use kvm_ioctls::*;
 use utils::eventfd::EventFd;
 use utils::signal::{register_signal_handler, sigrtmin, Killable};
@@ -103,7 +106,9 @@ pub enum Error {
     /// Error setting up the global interrupt controller.
     SetupGIC(arch::aarch64::gic::Error),
     /// Cannot set the memory regions.
-    SetUserMemoryRegion(kvm_ioctls::Error),
+    SetUserMemoryRegion2(kvm_ioctls::Error),
+    /// Unable to set memory region attributes.
+    SetMemoryAttributes(kvm_ioctls::Error),
     /// Error creating memory map for SHM region.
     ShmMmap(io::Error),
     #[cfg(feature = "amd-sev")]
@@ -255,7 +260,8 @@ impl Display for Error {
                 f,
                 "Cannot set the local interruption due to bad configuration: {e:?}"
             ),
-            SetUserMemoryRegion(e) => write!(f, "Cannot set the memory regions: {e}"),
+            SetUserMemoryRegion2(e) => write!(f, "Cannot set the memory regions: {e}"),
+            SetMemoryAttributes(e) => write!(f, "Unable to set memory attributes: {e}"),
             ShmMmap(e) => write!(f, "Error creating memory map for SHM region: {e}"),
             #[cfg(feature = "tee")]
             SnpSecVirtInit(e) => write!(
@@ -526,20 +532,47 @@ impl Vm {
             // It's safe to unwrap because the guest address is valid.
             let host_addr = guest_mem.get_host_address(region.start_addr()).unwrap();
             debug!("Guest memory starts at {:x?}", host_addr);
-            let memory_region = kvm_userspace_memory_region {
+
+            let guest_memfd = self
+                .fd
+                .create_guest_memfd(kvm_create_guest_memfd {
+                    size: region.size() as u64,
+                    flags: 0,
+                    reserved: [0; 6],
+                })
+                .unwrap();
+
+            let memory_region = kvm_userspace_memory_region2 {
                 slot: self.next_mem_slot,
+                flags: KVM_MEM_GUEST_MEMFD,
                 guest_phys_addr: region.start_addr().raw_value(),
                 memory_size: region.len(),
                 userspace_addr: host_addr as u64,
-                flags: 0,
+                guest_memfd_offset: 0,
+                guest_memfd: guest_memfd as u32,
+                pad1: 0,
+                pad2: [0; 14],
             };
+
             // Safe because we mapped the memory region, we made sure that the regions
             // are not overlapping.
             unsafe {
                 self.fd
-                    .set_user_memory_region(memory_region)
-                    .map_err(Error::SetUserMemoryRegion)?;
+                    .set_user_memory_region2(memory_region)
+                    .map_err(Error::SetUserMemoryRegion2)?;
             };
+
+            let attr = kvm_memory_attributes {
+                address: region.start_addr().raw_value(),
+                size: region.len(),
+                attributes: KVM_MEMORY_ATTRIBUTE_PRIVATE as u64,
+                flags: 0,
+            };
+
+            self.fd
+                .set_memory_attributes(attr)
+                .map_err(Error::SetMemoryAttributes)?;
+
             self.next_mem_slot += 1;
         }