misc: Stop using deprecated functions from vm-memory crate

See: https://github.com/rust-vmm/vm-memory/pull/247

Signed-off-by: Bo Chen <chen.bo@intel.com>

arch/src/aarch64/uefi.rs

@@ -1,8 +1,9 @@
 // Copyright 2020 Arm Limited (or its affiliates). All rights reserved.
 
 use std::io::{Read, Seek, SeekFrom};
+use std::os::fd::AsFd;
 use std::result;
-use vm_memory::{Bytes, GuestAddress, GuestMemory};
+use vm_memory::{GuestAddress, GuestMemory};
 
 /// Errors thrown while loading UEFI binary
 #[derive(Debug)]
@@ -24,7 +25,7 @@ pub fn load_uefi<F, M: GuestMemory>(
     uefi_image: &mut F,
 ) -> Result<()>
 where
-    F: Read + Seek,
+    F: Read + Seek + AsFd,
 {
     let uefi_size = uefi_image
         .seek(SeekFrom::End(0))
@@ -36,6 +37,6 @@ where
     }
     uefi_image.rewind().map_err(|_| Error::SeekUefiStart)?;
     guest_mem
-        .read_exact_from(guest_addr, uefi_image, uefi_size)
+        .read_exact_volatile_from(guest_addr, &mut uefi_image.as_fd(), uefi_size)
         .map_err(|_| Error::ReadUefiImage)
 }

arch/src/x86_64/mptable.rs

@@ -9,7 +9,6 @@ use crate::layout::{APIC_START, HIGH_RAM_START, IOAPIC_START};
 use crate::x86_64::mpspec;
 use crate::GuestMemoryMmap;
 use libc::c_char;
-use std::io;
 use std::mem;
 use std::result;
 use std::slice;
@@ -154,7 +153,7 @@ pub fn setup_mptable(offset: GuestAddress, mem: &GuestMemoryMmap, num_cpus: u8)
         return Err(Error::AddressOverflow);
     }
 
-    mem.read_exact_from(base_mp, &mut io::repeat(0), mp_size)
+    mem.read_exact_volatile_from(base_mp, &mut vec![0; mp_size].as_slice(), mp_size)
         .map_err(Error::Clear)?;
 
     {
@@ -291,7 +290,10 @@ pub fn setup_mptable(offset: GuestAddress, mem: &GuestMemoryMmap, num_cpus: u8)
 mod tests {
     use super::*;
     use crate::layout::MPTABLE_START;
-    use vm_memory::{GuestAddress, GuestUsize};
+    use vm_memory::{
+        bitmap::BitmapSlice, GuestAddress, GuestUsize, VolatileMemoryError, VolatileSlice,
+        WriteVolatile,
+    };
 
     fn table_entry_size(type_: u8) -> usize {
         match type_ as u32 {
@@ -351,20 +353,24 @@ mod tests {
         let mpc_table: MpcTableWrapper = mem.read_obj(mpc_offset).unwrap();
 
         struct Sum(u8);
-        impl io::Write for Sum {
-            fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
-                for v in buf.iter() {
+        impl WriteVolatile for Sum {
+            fn write_volatile<B: BitmapSlice>(
+                &mut self,
+                buf: &VolatileSlice<B>,
+            ) -> result::Result<usize, VolatileMemoryError> {
+                let mut tmp = vec![0u8; buf.len()];
+                tmp.write_all_volatile(buf)?;
+
+                for v in tmp.iter() {
                     self.0 = self.0.wrapping_add(*v);
                 }
+
                 Ok(buf.len())
             }
-            fn flush(&mut self) -> io::Result<()> {
-                Ok(())
-            }
         }
 
         let mut sum = Sum(0);
-        mem.write_to(mpc_offset, &mut sum, mpc_table.0.length as usize)
+        mem.write_volatile_to(mpc_offset, &mut sum, mpc_table.0.length as usize)
             .unwrap();
         assert_eq!(sum.0, 0);
     }