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| author | Richard Henderson <richard.henderson@linaro.org> | 2025-09-18 07:05:58 -0700 |
|---|---|---|
| committer | Richard Henderson <richard.henderson@linaro.org> | 2025-09-18 07:05:59 -0700 |
| commit | ccafa85a97e38698b798115bba6c18c849846e25 (patch) | |
| tree | a7d4941f050d4b621cffe2a71657a1bd39c35d4b /rust/qemu-api/src/chardev.rs | |
| parent | f0007b7f03e2d7fc33e71c3a582f2364c51a226b (diff) | |
| parent | 00c0911c68e5bd664de1a261b74c390f4c0be83d (diff) | |
| download | focaccia-qemu-ccafa85a97e38698b798115bba6c18c849846e25.tar.gz focaccia-qemu-ccafa85a97e38698b798115bba6c18c849846e25.zip | |
Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into staging
* cpu-exec: more cleanups to CPU loop exits * python: bump bundled Meson to 1.9.0 * rust: require Rust 1.83.0 * rust: temporarily remove from Ubuntu CI * rust: vmstate: convert to use builder pattern * rust: split "qemu-api" crate * rust: rename qemu_api_macros -> qemu_macros * rust: re-export qemu macros from other crates * x86: fix functional test failure for Xen emulation * x86: cleanups # -----BEGIN PGP SIGNATURE----- # # iQFIBAABCgAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmjK6ZsUHHBib256aW5p # QHJlZGhhdC5jb20ACgkQv/vSX3jHroNBKwf/aadInCT4vASOfpxbwZgYfYgR2m2m # BJE9oYKxZJ6MlEOU/1Wfywf9fg4leMSh3XxkDKkEIL19yS6emwin8n3SNYrdAFn3 # 6u4IIWO4NI1Ht3NKytrqFk9wtbH9pAs/gVHLlnmpMxIqtOtZLumPAKNz8rlantmK # UVDYL3Y0L4pD9i5FK1ObMNpk5AsWNr8Tr64fmb+nTkHutld3sBrEMCLI0+EByGyN # lQ16sLn9PGqHOr210zuQP7wP2T3NCI3YokFSPQrUUL8LZGxRdXoNF4hI4uZDKGdn # UbtRu9EkM052qzfsFMrEw5JSbdxEfIjKlPoFKseMv+aWvNAuximAraD3Vg== # =Lr+x # -----END PGP SIGNATURE----- # gpg: Signature made Wed 17 Sep 2025 10:02:19 AM PDT # gpg: using RSA key F13338574B662389866C7682BFFBD25F78C7AE83 # gpg: issuer "pbonzini@redhat.com" # gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [unknown] # gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" [unknown] # gpg: WARNING: The key's User ID is not certified with a trusted signature! # gpg: There is no indication that the signature belongs to the owner. # Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1 # Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83 * tag 'for-upstream' of https://gitlab.com/bonzini/qemu: (60 commits) accel/kvm: Set guest_memfd_offset to non-zero value only when guest_memfd is valid accel/kvm: Zero out mem explicitly in kvm_set_user_memory_region() accel/kvm: Switch to check KVM_CAP_GUEST_MEMFD and KVM_CAP_USER_MEMORY2 on VM i386/kvm: Drop KVM_CAP_X86_SMM check in kvm_arch_init() multiboot: Fix the split lock target/i386: Define enum X86ASIdx for x86's address spaces i386/cpu: Enable SMM cpu address space under KVM hpet: guard IRQ handling with BQL rust: do not inline do_init_io rust: meson: remove unnecessary complication in device crates docs: update rust.rst rust: re-export qemu macros from common/qom/hwcore rust: re-export qemu_macros internal helper in "bits" rust: repurpose qemu_api -> tests rust/pl011: drop dependency on qemu_api rust/hpet: drop now unneeded qemu_api dep rust: rename qemu_api_macros -> qemu_macros rust: split "hwcore" crate rust: split "system" crate rust: split "chardev" crate ... Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'rust/qemu-api/src/chardev.rs')
| -rw-r--r-- | rust/qemu-api/src/chardev.rs | 260 |
1 files changed, 0 insertions, 260 deletions
diff --git a/rust/qemu-api/src/chardev.rs b/rust/qemu-api/src/chardev.rs deleted file mode 100644 index 6e0590d758..0000000000 --- a/rust/qemu-api/src/chardev.rs +++ /dev/null @@ -1,260 +0,0 @@ -// Copyright 2024 Red Hat, Inc. -// Author(s): Paolo Bonzini <pbonzini@redhat.com> -// SPDX-License-Identifier: GPL-2.0-or-later - -//! Bindings for character devices -//! -//! Character devices in QEMU can run under the big QEMU lock or in a separate -//! `GMainContext`. Here we only support the former, because the bindings -//! enforce that the BQL is taken whenever the functions in [`CharBackend`] are -//! called. - -use std::{ - ffi::{c_int, c_void, CStr}, - fmt::{self, Debug}, - io::{self, ErrorKind, Write}, - marker::PhantomPinned, - ptr::addr_of_mut, - slice, -}; - -use crate::{ - bindings, - callbacks::FnCall, - cell::{BqlRefMut, Opaque}, - prelude::*, -}; - -/// A safe wrapper around [`bindings::Chardev`]. -#[repr(transparent)] -#[derive(qemu_api_macros::Wrapper)] -pub struct Chardev(Opaque<bindings::Chardev>); - -pub type ChardevClass = bindings::ChardevClass; -pub type Event = bindings::QEMUChrEvent; - -/// A safe wrapper around [`bindings::CharBackend`], denoting the character -/// back-end that is used for example by a device. Compared to the -/// underlying C struct it adds BQL protection, and is marked as pinned -/// because the QOM object ([`bindings::Chardev`]) contains a pointer to -/// the `CharBackend`. -pub struct CharBackend { - inner: BqlRefCell<bindings::CharBackend>, - _pin: PhantomPinned, -} - -impl Write for BqlRefMut<'_, bindings::CharBackend> { - fn flush(&mut self) -> io::Result<()> { - Ok(()) - } - - fn write(&mut self, buf: &[u8]) -> io::Result<usize> { - let chr: &mut bindings::CharBackend = self; - - let len = buf.len().try_into().unwrap(); - let r = unsafe { bindings::qemu_chr_fe_write(addr_of_mut!(*chr), buf.as_ptr(), len) }; - errno::into_io_result(r).map(|cnt| cnt as usize) - } - - fn write_all(&mut self, buf: &[u8]) -> io::Result<()> { - let chr: &mut bindings::CharBackend = self; - - let len = buf.len().try_into().unwrap(); - let r = unsafe { bindings::qemu_chr_fe_write_all(addr_of_mut!(*chr), buf.as_ptr(), len) }; - errno::into_io_result(r).and_then(|cnt| { - if cnt as usize == buf.len() { - Ok(()) - } else { - Err(ErrorKind::WriteZero.into()) - } - }) - } -} - -impl Debug for CharBackend { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - // SAFETY: accessed just to print the values - let chr = self.inner.as_ptr(); - Debug::fmt(unsafe { &*chr }, f) - } -} - -// FIXME: use something like PinnedDrop from the pinned_init crate -impl Drop for CharBackend { - fn drop(&mut self) { - self.disable_handlers(); - } -} - -impl CharBackend { - /// Enable the front-end's character device handlers, if there is an - /// associated `Chardev`. - pub fn enable_handlers< - 'chardev, - 'owner: 'chardev, - T, - CanReceiveFn: for<'a> FnCall<(&'a T,), u32>, - ReceiveFn: for<'a, 'b> FnCall<(&'a T, &'b [u8])>, - EventFn: for<'a> FnCall<(&'a T, Event)>, - >( - // When "self" is dropped, the handlers are automatically disabled. - // However, this is not necessarily true if the owner is dropped. - // So require the owner to outlive the character device. - &'chardev self, - owner: &'owner T, - _can_receive: CanReceiveFn, - _receive: ReceiveFn, - _event: EventFn, - ) { - unsafe extern "C" fn rust_can_receive_cb<T, F: for<'a> FnCall<(&'a T,), u32>>( - opaque: *mut c_void, - ) -> c_int { - // SAFETY: the values are safe according to the contract of - // enable_handlers() and qemu_chr_fe_set_handlers() - let owner: &T = unsafe { &*(opaque.cast::<T>()) }; - let r = F::call((owner,)); - r.try_into().unwrap() - } - - unsafe extern "C" fn rust_receive_cb<T, F: for<'a, 'b> FnCall<(&'a T, &'b [u8])>>( - opaque: *mut c_void, - buf: *const u8, - size: c_int, - ) { - // SAFETY: the values are safe according to the contract of - // enable_handlers() and qemu_chr_fe_set_handlers() - let owner: &T = unsafe { &*(opaque.cast::<T>()) }; - let buf = unsafe { slice::from_raw_parts(buf, size.try_into().unwrap()) }; - F::call((owner, buf)) - } - - unsafe extern "C" fn rust_event_cb<T, F: for<'a> FnCall<(&'a T, Event)>>( - opaque: *mut c_void, - event: Event, - ) { - // SAFETY: the values are safe according to the contract of - // enable_handlers() and qemu_chr_fe_set_handlers() - let owner: &T = unsafe { &*(opaque.cast::<T>()) }; - F::call((owner, event)) - } - - let _: () = CanReceiveFn::ASSERT_IS_SOME; - let receive_cb: Option<unsafe extern "C" fn(*mut c_void, *const u8, c_int)> = - if ReceiveFn::is_some() { - Some(rust_receive_cb::<T, ReceiveFn>) - } else { - None - }; - let event_cb: Option<unsafe extern "C" fn(*mut c_void, Event)> = if EventFn::is_some() { - Some(rust_event_cb::<T, EventFn>) - } else { - None - }; - - let mut chr = self.inner.borrow_mut(); - // SAFETY: the borrow promises that the BQL is taken - unsafe { - bindings::qemu_chr_fe_set_handlers( - addr_of_mut!(*chr), - Some(rust_can_receive_cb::<T, CanReceiveFn>), - receive_cb, - event_cb, - None, - (owner as *const T).cast_mut().cast::<c_void>(), - core::ptr::null_mut(), - true, - ); - } - } - - /// Disable the front-end's character device handlers. - pub fn disable_handlers(&self) { - let mut chr = self.inner.borrow_mut(); - // SAFETY: the borrow promises that the BQL is taken - unsafe { - bindings::qemu_chr_fe_set_handlers( - addr_of_mut!(*chr), - None, - None, - None, - None, - core::ptr::null_mut(), - core::ptr::null_mut(), - true, - ); - } - } - - /// Notify that the frontend is ready to receive data. - pub fn accept_input(&self) { - let mut chr = self.inner.borrow_mut(); - // SAFETY: the borrow promises that the BQL is taken - unsafe { bindings::qemu_chr_fe_accept_input(addr_of_mut!(*chr)) } - } - - /// Temporarily borrow the character device, allowing it to be used - /// as an implementor of `Write`. Note that it is not valid to drop - /// the big QEMU lock while the character device is borrowed, as - /// that might cause C code to write to the character device. - pub fn borrow_mut(&self) -> impl Write + '_ { - self.inner.borrow_mut() - } - - /// Send a continuous stream of zero bits on the line if `enabled` is - /// true, or a short stream if `enabled` is false. - pub fn send_break(&self, long: bool) -> io::Result<()> { - let mut chr = self.inner.borrow_mut(); - let mut duration: c_int = long.into(); - // SAFETY: the borrow promises that the BQL is taken - let r = unsafe { - bindings::qemu_chr_fe_ioctl( - addr_of_mut!(*chr), - bindings::CHR_IOCTL_SERIAL_SET_BREAK as i32, - addr_of_mut!(duration).cast::<c_void>(), - ) - }; - - errno::into_io_result(r).map(|_| ()) - } - - /// Write data to a character backend from the front end. This function - /// will send data from the front end to the back end. Unlike - /// `write`, this function will block if the back end cannot - /// consume all of the data attempted to be written. - /// - /// Returns the number of bytes consumed (0 if no associated Chardev) or an - /// error. - pub fn write(&self, buf: &[u8]) -> io::Result<usize> { - let len = buf.len().try_into().unwrap(); - // SAFETY: qemu_chr_fe_write is thread-safe - let r = unsafe { bindings::qemu_chr_fe_write(self.inner.as_ptr(), buf.as_ptr(), len) }; - errno::into_io_result(r).map(|cnt| cnt as usize) - } - - /// Write data to a character backend from the front end. This function - /// will send data from the front end to the back end. Unlike - /// `write`, this function will block if the back end cannot - /// consume all of the data attempted to be written. - /// - /// Returns the number of bytes consumed (0 if no associated Chardev) or an - /// error. - pub fn write_all(&self, buf: &[u8]) -> io::Result<()> { - let len = buf.len().try_into().unwrap(); - // SAFETY: qemu_chr_fe_write_all is thread-safe - let r = unsafe { bindings::qemu_chr_fe_write_all(self.inner.as_ptr(), buf.as_ptr(), len) }; - errno::into_io_result(r).and_then(|cnt| { - if cnt as usize == buf.len() { - Ok(()) - } else { - Err(ErrorKind::WriteZero.into()) - } - }) - } -} - -unsafe impl ObjectType for Chardev { - type Class = ChardevClass; - const TYPE_NAME: &'static CStr = - unsafe { CStr::from_bytes_with_nul_unchecked(bindings::TYPE_CHARDEV) }; -} -qom_isa!(Chardev: Object); |