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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /rust/syn/thread.rs
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
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Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
Diffstat (limited to 'rust/syn/thread.rs')
-rw-r--r--rust/syn/thread.rs62
1 files changed, 62 insertions, 0 deletions
diff --git a/rust/syn/thread.rs b/rust/syn/thread.rs
new file mode 100644
index 000000000..4165a173d
--- /dev/null
+++ b/rust/syn/thread.rs
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
+use std::fmt::{self, Debug};
+use std::thread::{self, ThreadId};
+
+/// ThreadBound is a Sync-maker and Send-maker that allows accessing a value
+/// of type T only from the original thread on which the ThreadBound was
+/// constructed.
+pub(crate) struct ThreadBound<T> {
+ value: T,
+ thread_id: ThreadId,
+}
+
+unsafe impl<T> Sync for ThreadBound<T> {}
+
+// Send bound requires Copy, as otherwise Drop could run in the wrong place.
+//
+// Today Copy and Drop are mutually exclusive so `T: Copy` implies `T: !Drop`.
+// This impl needs to be revisited if that restriction is relaxed in the future.
+unsafe impl<T: Copy> Send for ThreadBound<T> {}
+
+impl<T> ThreadBound<T> {
+ pub(crate) fn new(value: T) -> Self {
+ ThreadBound {
+ value,
+ thread_id: thread::current().id(),
+ }
+ }
+
+ pub(crate) fn get(&self) -> Option<&T> {
+ if thread::current().id() == self.thread_id {
+ Some(&self.value)
+ } else {
+ None
+ }
+ }
+}
+
+impl<T: Debug> Debug for ThreadBound<T> {
+ fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ match self.get() {
+ Some(value) => Debug::fmt(value, formatter),
+ None => formatter.write_str("unknown"),
+ }
+ }
+}
+
+// Copy the bytes of T, even if the currently running thread is the "wrong"
+// thread. This is fine as long as the original thread is not simultaneously
+// mutating this value via interior mutability, which would be a data race.
+//
+// Currently `T: Copy` is sufficient to guarantee that T contains no interior
+// mutability, because _all_ interior mutability in Rust is built on
+// std::cell::UnsafeCell, which has no Copy impl. This impl needs to be
+// revisited if that restriction is relaxed in the future.
+impl<T: Copy> Copy for ThreadBound<T> {}
+
+impl<T: Copy> Clone for ThreadBound<T> {
+ fn clone(&self) -> Self {
+ *self
+ }
+}