build: Address issues found by 1.43.0 clippy

These are mostly due to use of "bare use" statements and unnecessary vector
creation.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>

vm-virtio/src/block.rs

@@ -15,7 +15,6 @@ use super::{
 };
 use crate::VirtioInterrupt;
 use anyhow::anyhow;
-use epoll;
 use libc::{c_void, EFD_NONBLOCK};
 use serde::ser::{Serialize, SerializeStruct, Serializer};
 use std::alloc::{alloc_zeroed, dealloc, Layout};

vm-virtio/src/console.rs

@@ -8,10 +8,8 @@ use super::{
 };
 use crate::VirtioInterrupt;
 use anyhow::anyhow;
-use epoll;
 use libc::EFD_NONBLOCK;
 use serde::ser::{Serialize, SerializeStruct, Serializer};
-use std;
 use std::cmp;
 use std::collections::VecDeque;
 use std::fs::File;

vm-virtio/src/iommu.rs

@@ -9,7 +9,6 @@ use super::{
 };
 use crate::{DmaRemapping, VirtioInterrupt, VirtioInterruptType};
 use anyhow::anyhow;
-use epoll;
 use libc::EFD_NONBLOCK;
 use std::cmp;
 use std::collections::BTreeMap;

vm-virtio/src/mem.rs

@@ -18,8 +18,6 @@ use super::{
     VirtioDeviceType, VIRTIO_F_VERSION_1,
 };
 use crate::{VirtioInterrupt, VirtioInterruptType};
-use epoll;
-use libc;
 use libc::EFD_NONBLOCK;
 use std::cmp;
 use std::fs::File;

vm-virtio/src/net.rs

@@ -16,7 +16,6 @@ use super::{
 };
 use crate::VirtioInterrupt;
 use anyhow::anyhow;
-use epoll;
 use libc::EAGAIN;
 use libc::EFD_NONBLOCK;
 use net_util::{MacAddr, Tap};

vm-virtio/src/pmem.rs

@@ -13,7 +13,6 @@ use super::{
 };
 use crate::{VirtioInterrupt, VirtioInterruptType};
 use anyhow::anyhow;
-use epoll;
 use libc::EFD_NONBLOCK;
 use serde::ser::{Serialize, SerializeStruct, Serializer};
 use std::cmp;

vm-virtio/src/rng.rs

@@ -9,9 +9,7 @@ use super::{
 };
 use crate::{VirtioInterrupt, VirtioInterruptType};
 use anyhow::anyhow;
-use epoll;
 use libc::EFD_NONBLOCK;
-use std;
 use std::fs::File;
 use std::io;
 use std::os::unix::io::{AsRawFd, FromRawFd};

vm-virtio/src/vhost_user/blk.rs

@@ -8,7 +8,6 @@ use super::Error as DeviceError;
 use super::{Error, Result};
 use crate::block::VirtioBlockConfig;
 use crate::VirtioInterrupt;
-use libc;
 use libc::EFD_NONBLOCK;
 use std::cmp;
 use std::io::Write;

vm-virtio/src/vhost_user/handler.rs

@@ -9,7 +9,6 @@
 
 use super::super::{Queue, VirtioInterruptType};
 use super::{Error, Result};
-use epoll;
 use vmm_sys_util::eventfd::EventFd;
 
 use crate::VirtioInterrupt;

vm-virtio/src/vhost_user/mod.rs

@@ -7,7 +7,6 @@ extern crate vhost_rs;
 extern crate virtio_bindings;
 extern crate vm_memory;
 
-use std;
 use std::io;
 use vhost_rs::Error as VhostError;
 use vm_memory::Error as MmapError;

vm-virtio/src/vhost_user/net.rs

@@ -11,7 +11,6 @@ use super::vu_common_ctrl::*;
 use super::Error as DeviceError;
 use super::{Error, Result};
 use crate::VirtioInterrupt;
-use libc;
 use libc::EFD_NONBLOCK;
 use net_util::MacAddr;
 use std::cmp;

vm-virtio/src/vhost_user/vu_common_ctrl.rs

@@ -1,25 +1,21 @@
 // Copyright 2019 Intel Corporation. All Rights Reserved.
 // SPDX-License-Identifier: Apache-2.0
 
-use libc;
+use super::super::Queue;
+use super::{Error, Result};
+use crate::queue::Descriptor;
+use crate::{VirtioInterrupt, VirtioInterruptType};
 use libc::EFD_NONBLOCK;
 use std::convert::TryInto;
 use std::os::unix::io::AsRawFd;
 use std::sync::Arc;
 use std::vec::Vec;
-
-use crate::queue::Descriptor;
-use crate::{VirtioInterrupt, VirtioInterruptType};
-
+use vhost_rs::vhost_user::{Master, VhostUserMaster};
+use vhost_rs::{VhostBackend, VhostUserMemoryRegionInfo, VringConfigData};
 use vm_device::get_host_address_range;
 use vm_memory::{Address, Error as MmapError, GuestMemory, GuestMemoryMmap, GuestMemoryRegion};
 use vmm_sys_util::eventfd::EventFd;
 
-use super::super::Queue;
-use super::{Error, Result};
-use vhost_rs::vhost_user::{Master, VhostUserMaster};
-use vhost_rs::{VhostBackend, VhostUserMemoryRegionInfo, VringConfigData};
-
 #[derive(Debug, Clone)]
 pub struct VhostUserConfig {
     pub sock: String,

vm-virtio/src/vsock/device.rs

@@ -36,9 +36,7 @@ use anyhow::anyhow;
 /// - a backend FD.
 ///
 use byteorder::{ByteOrder, LittleEndian};
-use epoll;
 use libc::EFD_NONBLOCK;
-use std;
 use std::fs::File;
 use std::io;
 use std::os::unix::io::{AsRawFd, FromRawFd};
@@ -688,15 +686,13 @@ mod tests {
             VirtioDeviceType::TYPE_VSOCK as u32
         );
         assert_eq!(ctx.device.queue_max_sizes(), QUEUE_SIZES);
-        assert_eq!((ctx.device.features() >> (0 * 32)) as u32, device_pages[0]);
-        assert_eq!((ctx.device.features() >> (1 * 32)) as u32, device_pages[1]);
+        assert_eq!(ctx.device.features() as u32, device_pages[0]);
+        assert_eq!((ctx.device.features() >> 32) as u32, device_pages[1]);
 
         // Ack device features, page 0.
-        ctx.device
-            .ack_features(u64::from(driver_pages[0]) << (0 * 32));
+        ctx.device.ack_features(u64::from(driver_pages[0]));
         // Ack device features, page 1.
-        ctx.device
-            .ack_features(u64::from(driver_pages[1]) << (1 * 32));
+        ctx.device.ack_features(u64::from(driver_pages[1]) << 32);
         // Check that no side effect are present, and that the acked features are exactly the same
         // as the device features.
         assert_eq!(ctx.device.acked_features, device_features & driver_features);