uefi: Add PCI memory device for testing

Author: tmvkrpxl0

xtask/src/qemu.rs

@@ -481,6 +481,13 @@ pub fn run_qemu(arch: UefiArch, opt: &QemuOpt) -> Result<()> {
     cmd.arg("-device");
     cmd.arg("ide-hd,drive=satadisk0,bus=ide.2,serial=AtaPassThru,model=AtaPassThru");
 
+    // Sixth shared memory device used for testing Pci Root Bridge I/O's Copy function.
+    // This is to provide a PCI device with large enough memory.
+    cmd.arg("-device");
+    cmd.arg("ivshmem-plain,memdev=hostmem,id=hostmem");
+    cmd.arg("-object");
+    cmd.arg("memory-backend-file,size=1M,share,mem-path=/dev/shm/ivshmem,id=hostmem");
+
     let qemu_monitor_pipe = Pipe::new(tmp_dir, "qemu-monitor")?;
     let serial_pipe = Pipe::new(tmp_dir, "serial")?;