Not a major change but, as a small but significant step in creating
qdev bindings, show how pl011_create can be written without "unsafe"
calls (apart from converting pointers to references).
This also provides a starting point for creating Error** bindings.
Reviewed-by: Zhao Liu <zhao1....@intel.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
rust/hw/char/pl011/src/device.rs | 37 ++++++++++++++++----------------
rust/qemu-api/src/sysbus.rs | 34 ++++++++++++++++++++++++++---
2 files changed, 49 insertions(+), 22 deletions(-)
diff --git a/rust/hw/char/pl011/src/device.rs b/rust/hw/char/pl011/src/device.rs
index 4e959073711..fe73771021e 100644
--- a/rust/hw/char/pl011/src/device.rs
+++ b/rust/hw/char/pl011/src/device.rs
@@ -10,14 +10,12 @@
use qemu_api::{
bindings::{
- error_fatal, qdev_prop_set_chr, qemu_chr_fe_accept_input,
qemu_chr_fe_ioctl,
- qemu_chr_fe_set_handlers, qemu_chr_fe_write_all, qemu_irq,
sysbus_connect_irq,
- sysbus_mmio_map, sysbus_realize, CharBackend, QEMUChrEvent,
- CHR_IOCTL_SERIAL_SET_BREAK,
+ qemu_chr_fe_accept_input, qemu_chr_fe_ioctl, qemu_chr_fe_set_handlers,
+ qemu_chr_fe_write_all, CharBackend, QEMUChrEvent,
CHR_IOCTL_SERIAL_SET_BREAK,
},
chardev::Chardev,
- c_str, impl_vmstate_forward,
- irq::InterruptSource,
+ impl_vmstate_forward,
+ irq::{IRQState, InterruptSource},
memory::{hwaddr, MemoryRegion, MemoryRegionOps, MemoryRegionOpsBuilder},
prelude::*,
qdev::{Clock, ClockEvent, DeviceImpl, DeviceState, Property, ResetType,
ResettablePhasesImpl},
@@ -698,26 +696,27 @@ pub fn post_load(&self, _version_id: u32) -> Result<(),
()> {
/// # Safety
///
-/// We expect the FFI user of this function to pass a valid pointer for `chr`.
+/// We expect the FFI user of this function to pass a valid pointer for `chr`
+/// and `irq`.
#[no_mangle]
pub unsafe extern "C" fn pl011_create(
addr: u64,
- irq: qemu_irq,
+ irq: *mut IRQState,
chr: *mut Chardev,
) -> *mut DeviceState {
- let pl011 = PL011State::new();
- unsafe {
- let dev = pl011.as_mut_ptr::<DeviceState>();
- qdev_prop_set_chr(dev, c_str!("chardev").as_ptr(), chr);
+ // SAFETY: The callers promise that they have owned references.
+ // They do not gift them to pl011_create, so use `Owned::from`.
+ let irq = unsafe { Owned::<IRQState>::from(&*irq) };
+ let chr = unsafe { Owned::<Chardev>::from(&*chr) };
- let sysbus = pl011.as_mut_ptr::<SysBusDevice>();
- sysbus_realize(sysbus, addr_of_mut!(error_fatal));
- sysbus_mmio_map(sysbus, 0, addr);
- sysbus_connect_irq(sysbus, 0, irq);
+ let dev = PL011State::new();
+ dev.prop_set_chr("chardev", &chr);
+ dev.sysbus_realize();
+ dev.mmio_map(0, addr);
+ dev.connect_irq(0, &irq);
- // return the pointer, which is kept alive by the QOM tree; drop owned
ref
- pl011.as_mut_ptr()
- }
+ // The pointer is kept alive by the QOM tree; drop the owned ref
+ dev.as_mut_ptr()
}
#[repr(C)]
diff --git a/rust/qemu-api/src/sysbus.rs b/rust/qemu-api/src/sysbus.rs
index c27dbf79e43..1f66a5f1e09 100644
--- a/rust/qemu-api/src/sysbus.rs
+++ b/rust/qemu-api/src/sysbus.rs
@@ -2,18 +2,18 @@
// Author(s): Paolo Bonzini <pbonz...@redhat.com>
// SPDX-License-Identifier: GPL-2.0-or-later
-use std::ffi::CStr;
+use std::{ffi::CStr, ptr::addr_of_mut};
pub use bindings::{SysBusDevice, SysBusDeviceClass};
use crate::{
bindings,
cell::bql_locked,
- irq::InterruptSource,
+ irq::{IRQState, InterruptSource},
memory::MemoryRegion,
prelude::*,
qdev::{DeviceClass, DeviceState},
- qom::ClassInitImpl,
+ qom::{ClassInitImpl, Owned},
};
unsafe impl ObjectType for SysBusDevice {
@@ -60,6 +60,34 @@ fn init_irq(&self, irq: &InterruptSource) {
bindings::sysbus_init_irq(self.as_mut_ptr(), irq.as_ptr());
}
}
+
+ // TODO: do we want a type like GuestAddress here?
+ fn mmio_map(&self, id: u32, addr: u64) {
+ assert!(bql_locked());
+ let id: i32 = id.try_into().unwrap();
+ unsafe {
+ bindings::sysbus_mmio_map(self.as_mut_ptr(), id, addr);
+ }
+ }
+
+ // Owned<> is used here because sysbus_connect_irq (via
+ // object_property_set_link) adds a reference to the IRQState,
+ // which can prolong its life
+ fn connect_irq(&self, id: u32, irq: &Owned<IRQState>) {
+ assert!(bql_locked());
+ let id: i32 = id.try_into().unwrap();
+ unsafe {
+ bindings::sysbus_connect_irq(self.as_mut_ptr(), id,
irq.as_mut_ptr());
+ }
+ }
+
+ fn sysbus_realize(&self) {
+ // TODO: return an Error
+ assert!(bql_locked());
+ unsafe {
+ bindings::sysbus_realize(self.as_mut_ptr(),
addr_of_mut!(bindings::error_fatal));
+ }
+ }
}
impl<R: ObjectDeref> SysBusDeviceMethods for R where R::Target:
IsA<SysBusDevice> {}
--
2.48.1
