[09/10] rust: pl011: pull device-specific code out of MemoryRegionOps callbacks

Commit Message

Paolo Bonzini Jan. 17, 2025, 9:26 a.m. UTC

read() can now return a simple u64.

Signed-off-by: Paolo Bonzini <[e-mail]>
---
 rust/hw/char/pl011/src/device.rs     | 16 +++++++++-------
 rust/hw/char/pl011/src/memory_ops.rs | 23 ++++-------------------
 2 files changed, 13 insertions(+), 26 deletions(-)

Patch

diff --git a/rust/hw/char/pl011/src/device.rs b/rust/hw/char/pl011/src/device.rs
index 6ecbfb9ac84..af0f451deb2 100644
--- a/rust/hw/char/pl011/src/device.rs
+++ b/rust/hw/char/pl011/src/device.rs
@@ -171,7 +171,7 @@  impl PL011Registers {
     pub(self) fn read(&mut self, offset: RegisterOffset) -> ControlFlow<u32, u32> {
         use RegisterOffset::*;
 
-        std::ops::ControlFlow::Break(match offset {
+        ControlFlow::Break(match offset {
             DR => {
                 self.flags.set_receive_fifo_full(false);
                 let c = self.read_fifo[self.read_pos];
@@ -530,22 +530,24 @@  fn post_init(&self) {
         }
     }
 
-    #[allow(clippy::needless_pass_by_ref_mut)]
-    pub fn read(&mut self, offset: hwaddr, _size: u32) -> ControlFlow<u64, u64> {
+    pub fn read(&mut self, offset: hwaddr, _size: u32) -> u64 {
         match RegisterOffset::try_from(offset) {
             Err(v) if (0x3f8..0x400).contains(&(v >> 2)) => {
                 let device_id = self.get_class().device_id;
-                ControlFlow::Break(u64::from(device_id[(offset - 0xfe0) >> 2]))
+                u64::from(device_id[(offset - 0xfe0) >> 2])
             }
             Err(_) => {
                 // qemu_log_mask(LOG_GUEST_ERROR, "pl011_read: Bad offset 0x%x\n", (int)offset);
-                ControlFlow::Break(0)
+                0
             }
             Ok(field) => match self.regs.borrow_mut().read(field) {
-                ControlFlow::Break(value) => ControlFlow::Break(value.into()),
+                ControlFlow::Break(value) => value.into(),
                 ControlFlow::Continue(value) => {
                     self.update();
-                    ControlFlow::Continue(value.into())
+                    unsafe {
+                        qemu_chr_fe_accept_input(&mut self.char_backend);
+                    }
+                    value.into()
                 },
             }
         }
diff --git a/rust/hw/char/pl011/src/memory_ops.rs b/rust/hw/char/pl011/src/memory_ops.rs
index 8f66c8d492c..95b4df794e4 100644
--- a/rust/hw/char/pl011/src/memory_ops.rs
+++ b/rust/hw/char/pl011/src/memory_ops.rs
@@ -26,26 +26,11 @@ 
 unsafe extern "C" fn pl011_read(opaque: *mut c_void, addr: hwaddr, size: c_uint) -> u64 {
     assert!(!opaque.is_null());
     let mut state = unsafe { NonNull::new_unchecked(opaque.cast::<PL011State>()) };
-    let val = unsafe { state.as_mut() }.read(addr, size);
-    match val {
-        std::ops::ControlFlow::Break(val) => val,
-        std::ops::ControlFlow::Continue(val) => {
-            // SAFETY: self.char_backend is a valid CharBackend instance after it's been
-            // initialized in realize().
-            let cb_ptr = unsafe { core::ptr::addr_of_mut!(state.as_mut().char_backend) };
-            unsafe {
-                qemu_chr_fe_accept_input(cb_ptr);
-            }
-
-            val
-        }
-    }
+    unsafe { state.as_mut() }.read(addr, size)
 }
 
 unsafe extern "C" fn pl011_write(opaque: *mut c_void, addr: hwaddr, data: u64, _size: c_uint) {
-    unsafe {
-        assert!(!opaque.is_null());
-        let mut state = NonNull::new_unchecked(opaque.cast::<PL011State>());
-        state.as_mut().write(addr, data)
-    }
+    assert!(!opaque.is_null());
+    let mut state = unsafe { NonNull::new_unchecked(opaque.cast::<PL011State>()) };
+    unsafe { state.as_mut() }.write(addr, data);
 }