refactor: don't duplicate VIRTIO_F_* constants in generated modules

Add a dedicated virtio_config.rs module that is bindgen'd from
virtio_config.h and contains exactly the VIRTIO_F constants. This avoid
the VIRTIO_F constants being redefined across bindgen'd modules for the
block, net and rng devices (or in the case of the balloon device, avoids
one device using another's bindgen module). Since this completely
eliminates all contents from virtio_rng.rs, delete that module.

Note that for some reason, my laptop's virtio_config.h was missing half
the constants, despite upstream 6.8 headers containing them. So I
bindgen'd this file on a .metal where all the constants were present in
the header.

Lastly, there's the question of the vsock modules, which has manually
written bindings in the uapi module, contained in `vsock/mod.rs`. I
tried autogenerating these, but bindgen chokes on the enum-constants
contained in virtio_vsock.h, so I'm leaving that as-is for now, apart
from deduplicating the VIRTIO_F_* constants.

Signed-off-by: Patrick Roy <[email protected]>

Author: roypat

src/vmm/src/devices/virtio/balloon/device.rs

@@ -25,7 +25,7 @@ use super::{
 };
 use crate::devices::virtio::balloon::BalloonError;
 use crate::devices::virtio::device::{IrqTrigger, IrqType};
-use crate::devices::virtio::generated::virtio_blk::VIRTIO_F_VERSION_1;
+use crate::devices::virtio::generated::virtio_config::VIRTIO_F_VERSION_1;
 use crate::logger::IncMetric;
 use crate::utils::u64_to_usize;
 use crate::vstate::memory::{Address, ByteValued, Bytes, GuestAddress, GuestMemoryMmap};

src/vmm/src/devices/virtio/block/vhost_user/device.rs

@@ -15,9 +15,8 @@ use vmm_sys_util::eventfd::EventFd;
 use super::{NUM_QUEUES, QUEUE_SIZE, VhostUserBlockError};
 use crate::devices::virtio::block::CacheType;
 use crate::devices::virtio::device::{DeviceState, IrqTrigger, IrqType, VirtioDevice};
-use crate::devices::virtio::generated::virtio_blk::{
-    VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_RO, VIRTIO_F_VERSION_1,
-};
+use crate::devices::virtio::generated::virtio_blk::{VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_RO};
+use crate::devices::virtio::generated::virtio_config::VIRTIO_F_VERSION_1;
 use crate::devices::virtio::generated::virtio_ring::VIRTIO_RING_F_EVENT_IDX;
 use crate::devices::virtio::queue::Queue;
 use crate::devices::virtio::vhost_user::{VhostUserHandleBackend, VhostUserHandleImpl};

src/vmm/src/devices/virtio/block/virtio/device.rs

@@ -25,8 +25,9 @@ use crate::devices::virtio::block::CacheType;
 use crate::devices::virtio::block::virtio::metrics::{BlockDeviceMetrics, BlockMetricsPerDevice};
 use crate::devices::virtio::device::{DeviceState, IrqTrigger, IrqType, VirtioDevice};
 use crate::devices::virtio::generated::virtio_blk::{
-    VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_RO, VIRTIO_BLK_ID_BYTES, VIRTIO_F_VERSION_1,
+    VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_RO, VIRTIO_BLK_ID_BYTES,
 };
+use crate::devices::virtio::generated::virtio_config::VIRTIO_F_VERSION_1;
 use crate::devices::virtio::generated::virtio_ring::VIRTIO_RING_F_EVENT_IDX;
 use crate::devices::virtio::queue::Queue;
 use crate::devices::virtio::{ActivateError, TYPE_BLOCK};

src/vmm/src/devices/virtio/generated/mod.rs

@@ -11,6 +11,6 @@
 #![allow(non_snake_case)]
 
 pub mod virtio_blk;
+pub mod virtio_config;
 pub mod virtio_net;
 pub mod virtio_ring;
-pub mod virtio_rng;

src/vmm/src/devices/virtio/generated/virtio_blk.rs

@@ -15,19 +15,6 @@
     unsafe_op_in_unsafe_fn
 )]
 
-pub const VIRTIO_F_NOTIFY_ON_EMPTY: u32 = 24;
-pub const VIRTIO_F_ANY_LAYOUT: u32 = 27;
-pub const VIRTIO_F_VERSION_1: u32 = 32;
-pub const VIRTIO_F_ACCESS_PLATFORM: u32 = 33;
-pub const VIRTIO_F_IOMMU_PLATFORM: u32 = 33;
-pub const VIRTIO_F_RING_PACKED: u32 = 34;
-pub const VIRTIO_F_IN_ORDER: u32 = 35;
-pub const VIRTIO_F_ORDER_PLATFORM: u32 = 36;
-pub const VIRTIO_F_SR_IOV: u32 = 37;
-pub const VIRTIO_F_NOTIFICATION_DATA: u32 = 38;
-pub const VIRTIO_F_NOTIF_CONFIG_DATA: u32 = 39;
-pub const VIRTIO_F_RING_RESET: u32 = 40;
-pub const VIRTIO_F_ADMIN_VQ: u32 = 41;
 pub const VIRTIO_BLK_F_SIZE_MAX: u32 = 1;
 pub const VIRTIO_BLK_F_SEG_MAX: u32 = 2;
 pub const VIRTIO_BLK_F_GEOMETRY: u32 = 4;

src/vmm/src/devices/virtio/generated/virtio_rng.rs renamed to src/vmm/src/devices/virtio/generated/virtio_config.rs

@@ -15,19 +15,6 @@
     unsafe_op_in_unsafe_fn
 )]
 
-pub const VIRTIO_F_NOTIFY_ON_EMPTY: u32 = 24;
-pub const VIRTIO_F_ANY_LAYOUT: u32 = 27;
-pub const VIRTIO_F_VERSION_1: u32 = 32;
-pub const VIRTIO_F_ACCESS_PLATFORM: u32 = 33;
-pub const VIRTIO_F_IOMMU_PLATFORM: u32 = 33;
-pub const VIRTIO_F_RING_PACKED: u32 = 34;
-pub const VIRTIO_F_IN_ORDER: u32 = 35;
-pub const VIRTIO_F_ORDER_PLATFORM: u32 = 36;
-pub const VIRTIO_F_SR_IOV: u32 = 37;
-pub const VIRTIO_F_NOTIFICATION_DATA: u32 = 38;
-pub const VIRTIO_F_NOTIF_CONFIG_DATA: u32 = 39;
-pub const VIRTIO_F_RING_RESET: u32 = 40;
-pub const VIRTIO_F_ADMIN_VQ: u32 = 41;
 pub const VIRTIO_NET_F_CSUM: u32 = 0;
 pub const VIRTIO_NET_F_GUEST_CSUM: u32 = 1;
 pub const VIRTIO_NET_F_CTRL_GUEST_OFFLOADS: u32 = 2;

src/vmm/src/devices/virtio/generated/virtio_net.rs

@@ -16,7 +16,7 @@ use vmm_sys_util::eventfd::EventFd;
 
 use super::NET_QUEUE_MAX_SIZE;
 use crate::devices::virtio::device::{DeviceState, IrqTrigger, IrqType, VirtioDevice};
-use crate::devices::virtio::generated::virtio_blk::VIRTIO_F_VERSION_1;
+use crate::devices::virtio::generated::virtio_config::VIRTIO_F_VERSION_1;
 use crate::devices::virtio::generated::virtio_net::{
     VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
     VIRTIO_NET_F_GUEST_UFO, VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_TSO6, VIRTIO_NET_F_HOST_UFO,

src/vmm/src/devices/virtio/net/device.rs

@@ -13,7 +13,7 @@ use super::metrics::METRICS;
 use super::{RNG_NUM_QUEUES, RNG_QUEUE};
 use crate::devices::DeviceError;
 use crate::devices::virtio::device::{DeviceState, IrqTrigger, IrqType, VirtioDevice};
-use crate::devices::virtio::generated::virtio_rng::VIRTIO_F_VERSION_1;
+use crate::devices::virtio::generated::virtio_config::VIRTIO_F_VERSION_1;
 use crate::devices::virtio::iov_deque::IovDequeError;
 use crate::devices::virtio::iovec::IoVecBufferMut;
 use crate::devices::virtio::queue::{FIRECRACKER_MAX_QUEUE_SIZE, Queue};

src/vmm/src/devices/virtio/rng/device.rs

@@ -31,6 +31,7 @@ use super::packet::{VSOCK_PKT_HDR_SIZE, VsockPacketRx, VsockPacketTx};
 use super::{VsockBackend, defs};
 use crate::devices::virtio::ActivateError;
 use crate::devices::virtio::device::{DeviceState, IrqTrigger, IrqType, VirtioDevice};
+use crate::devices::virtio::generated::virtio_config::{VIRTIO_F_IN_ORDER, VIRTIO_F_VERSION_1};
 use crate::devices::virtio::queue::Queue as VirtQueue;
 use crate::devices::virtio::vsock::VsockError;
 use crate::devices::virtio::vsock::metrics::METRICS;
@@ -49,7 +50,7 @@ pub(crate) const VIRTIO_VSOCK_EVENT_TRANSPORT_RESET: u32 = 0;
 /// - VIRTIO_F_IN_ORDER: the device returns used buffers in the same order that the driver makes
 ///   them available.
 pub(crate) const AVAIL_FEATURES: u64 =
-    (1 << uapi::VIRTIO_F_VERSION_1 as u64) | (1 << uapi::VIRTIO_F_IN_ORDER as u64);
+    (1 << VIRTIO_F_VERSION_1 as u64) | (1 << VIRTIO_F_IN_ORDER as u64);
 
 /// Structure representing the vsock device.
 #[derive(Debug)]