Merge tag 'char-misc-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-miscHEADtorvalds/mastertorvalds/HEADmaster

Pull Char/Misc/IIO/Binder updates from Greg KH:
 "Here is the big set of char/misc/iio and other driver subsystem
  changes for 6.18-rc1.

  Loads of different stuff in here, it was a busy development cycle in
  lots of different subsystems, with over 27k new lines added to the
  tree.

  Included in here are:

   - IIO updates including new drivers, reworking of existing apis, and
     other goodness in the sensor subsystems

   - MEI driver updates and additions

   - NVMEM driver updates

   - slimbus removal for an unused driver and some other minor updates

   - coresight driver updates and additions

   - MHI driver updates

   - comedi driver updates and fixes

   - extcon driver updates

   - interconnect driver additions

   - eeprom driver updates and fixes

   - minor UIO driver updates

   - tiny W1 driver updates

  But the majority of new code is in the rust bindings and additions,
  which includes:

   - misc driver rust binding updates for read/write support, we can now
     write "normal" misc drivers in rust fully, and the sample driver
     shows how this can be done.

   - Initial framework for USB driver rust bindings, which are disabled
     for now in the build, due to limited support, but coming in through
     this tree due to dependencies on other rust binding changes that
     were in here. I'll be enabling these back on in the build in the
     usb.git tree after -rc1 is out so that developers can continue to
     work on these in linux-next over the next development cycle.

   - Android Binder driver implemented in Rust.

     This is the big one, and was driving a huge majority of the rust
     binding work over the past years. Right now there are two binder
     drivers in the kernel, selected only at build time as to which one
     to use as binder wants to be included in the system at boot time.

     The binder C maintainers all agreed on this, as eventually, they
     want the C code to be removed from the tree, but it will take a few
     releases to get there while both are maintained to ensure that the
     rust implementation is fully stable and compliant with the existing
     userspace apis.

  All of these have been in linux-next for a while"

* tag 'char-misc-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (320 commits)
  rust: usb: keep usb::Device private for now
  rust: usb: don't retain device context for the interface parent
  USB: disable rust bindings from the build for now
  samples: rust: add a USB driver sample
  rust: usb: add basic USB abstractions
  coresight: Add label sysfs node support
  dt-bindings: arm: Add label in the coresight components
  coresight: tnoc: add new AMBA ID to support Trace Noc V2
  coresight: Fix incorrect handling for return value of devm_kzalloc
  coresight: tpda: fix the logic to setup the element size
  coresight: trbe: Return NULL pointer for allocation failures
  coresight: Refactor runtime PM
  coresight: Make clock sequence consistent
  coresight: Refactor driver data allocation
  coresight: Consolidate clock enabling
  coresight: Avoid enable programming clock duplicately
  coresight: Appropriately disable trace bus clocks
  coresight: Appropriately disable programming clocks
  coresight: etm4x: Support atclk
  coresight: catu: Support atclk
  ...

1 files changed, 1696 insertions, 0 deletions

diff --git a/drivers/android/binder/process.rs b/drivers/android/binder/process.rs
new file mode 100644
index 000000000000..f13a747e784c
--- /dev/null
+++ b/drivers/android/binder/process.rs
@@ -0,0 +1,1696 @@
+// SPDX-License-Identifier: GPL-2.0
+
+// Copyright (C) 2025 Google LLC.
+
+//! This module defines the `Process` type, which represents a process using a particular binder
+//! context.
+//!
+//! The `Process` object keeps track of all of the resources that this process owns in the binder
+//! context.
+//!
+//! There is one `Process` object for each binder fd that a process has opened, so processes using
+//! several binder contexts have several `Process` objects. This ensures that the contexts are
+//! fully separated.
+
+use core::mem::take;
+
+use kernel::{
+    bindings,
+    cred::Credential,
+    error::Error,
+    fs::file::{self, File},
+    list::{List, ListArc, ListArcField, ListLinks},
+    mm,
+    prelude::*,
+    rbtree::{self, RBTree, RBTreeNode, RBTreeNodeReservation},
+    seq_file::SeqFile,
+    seq_print,
+    sync::poll::PollTable,
+    sync::{
+        lock::{spinlock::SpinLockBackend, Guard},
+        Arc, ArcBorrow, CondVar, CondVarTimeoutResult, Mutex, SpinLock, UniqueArc,
+    },
+    task::Task,
+    types::ARef,
+    uaccess::{UserSlice, UserSliceReader},
+    uapi,
+    workqueue::{self, Work},
+};
+
+use crate::{
+    allocation::{Allocation, AllocationInfo, NewAllocation},
+    context::Context,
+    defs::*,
+    error::{BinderError, BinderResult},
+    node::{CouldNotDeliverCriticalIncrement, CritIncrWrapper, Node, NodeDeath, NodeRef},
+    page_range::ShrinkablePageRange,
+    range_alloc::{RangeAllocator, ReserveNew, ReserveNewArgs},
+    stats::BinderStats,
+    thread::{PushWorkRes, Thread},
+    BinderfsProcFile, DArc, DLArc, DTRWrap, DeliverToRead,
+};
+
+#[path = "freeze.rs"]
+mod freeze;
+use self::freeze::{FreezeCookie, FreezeListener};
+
+struct Mapping {
+    address: usize,
+    alloc: RangeAllocator<AllocationInfo>,
+}
+
+impl Mapping {
+    fn new(address: usize, size: usize) -> Self {
+        Self {
+            address,
+            alloc: RangeAllocator::new(size),
+        }
+    }
+}
+
+// bitflags for defer_work.
+const PROC_DEFER_FLUSH: u8 = 1;
+const PROC_DEFER_RELEASE: u8 = 2;
+
+/// The fields of `Process` protected by the spinlock.
+pub(crate) struct ProcessInner {
+    is_manager: bool,
+    pub(crate) is_dead: bool,
+    threads: RBTree<i32, Arc<Thread>>,
+    /// INVARIANT: Threads pushed to this list must be owned by this process.
+    ready_threads: List<Thread>,
+    nodes: RBTree<u64, DArc<Node>>,
+    mapping: Option<Mapping>,
+    work: List<DTRWrap<dyn DeliverToRead>>,
+    delivered_deaths: List<DTRWrap<NodeDeath>, 2>,
+
+    /// The number of requested threads that haven't registered yet.
+    requested_thread_count: u32,
+    /// The maximum number of threads used by the process thread pool.
+    max_threads: u32,
+    /// The number of threads the started and registered with the thread pool.
+    started_thread_count: u32,
+
+    /// Bitmap of deferred work to do.
+    defer_work: u8,
+
+    /// Number of transactions to be transmitted before processes in freeze_wait
+    /// are woken up.
+    outstanding_txns: u32,
+    /// Process is frozen and unable to service binder transactions.
+    pub(crate) is_frozen: bool,
+    /// Process received sync transactions since last frozen.
+    pub(crate) sync_recv: bool,
+    /// Process received async transactions since last frozen.
+    pub(crate) async_recv: bool,
+    pub(crate) binderfs_file: Option<BinderfsProcFile>,
+    /// Check for oneway spam
+    oneway_spam_detection_enabled: bool,
+}
+
+impl ProcessInner {
+    fn new() -> Self {
+        Self {
+            is_manager: false,
+            is_dead: false,
+            threads: RBTree::new(),
+            ready_threads: List::new(),
+            mapping: None,
+            nodes: RBTree::new(),
+            work: List::new(),
+            delivered_deaths: List::new(),
+            requested_thread_count: 0,
+            max_threads: 0,
+            started_thread_count: 0,
+            defer_work: 0,
+            outstanding_txns: 0,
+            is_frozen: false,
+            sync_recv: false,
+            async_recv: false,
+            binderfs_file: None,
+            oneway_spam_detection_enabled: false,
+        }
+    }
+
+    /// Schedule the work item for execution on this process.
+    ///
+    /// If any threads are ready for work, then the work item is given directly to that thread and
+    /// it is woken up. Otherwise, it is pushed to the process work list.
+    ///
+    /// This call can fail only if the process is dead. In this case, the work item is returned to
+    /// the caller so that the caller can drop it after releasing the inner process lock. This is
+    /// necessary since the destructor of `Transaction` will take locks that can't necessarily be
+    /// taken while holding the inner process lock.
+    pub(crate) fn push_work(
+        &mut self,
+        work: DLArc<dyn DeliverToRead>,
+    ) -> Result<(), (BinderError, DLArc<dyn DeliverToRead>)> {
+        // Try to find a ready thread to which to push the work.
+        if let Some(thread) = self.ready_threads.pop_front() {
+            // Push to thread while holding state lock. This prevents the thread from giving up
+            // (for example, because of a signal) when we're about to deliver work.
+            match thread.push_work(work) {
+                PushWorkRes::Ok => Ok(()),
+                PushWorkRes::FailedDead(work) => Err((BinderError::new_dead(), work)),
+            }
+        } else if self.is_dead {
+            Err((BinderError::new_dead(), work))
+        } else {
+            let sync = work.should_sync_wakeup();
+
+            // Didn't find a thread waiting for proc work; this can happen
+            // in two scenarios:
+            // 1. All threads are busy handling transactions
+            //    In that case, one of those threads should call back into
+            //    the kernel driver soon and pick up this work.
+            // 2. Threads are using the (e)poll interface, in which case
+            //    they may be blocked on the waitqueue without having been
+            //    added to waiting_threads. For this case, we just iterate
+            //    over all threads not handling transaction work, and
+            //    wake them all up. We wake all because we don't know whether
+            //    a thread that called into (e)poll is handling non-binder
+            //    work currently.
+            self.work.push_back(work);
+
+            // Wake up polling threads, if any.
+            for thread in self.threads.values() {
+                thread.notify_if_poll_ready(sync);
+            }
+
+            Ok(())
+        }
+    }
+
+    pub(crate) fn remove_node(&mut self, ptr: u64) {
+        self.nodes.remove(&ptr);
+    }
+
+    /// Updates the reference count on the given node.
+    pub(crate) fn update_node_refcount(
+        &mut self,
+        node: &DArc<Node>,
+        inc: bool,
+        strong: bool,
+        count: usize,
+        othread: Option<&Thread>,
+    ) {
+        let push = node.update_refcount_locked(inc, strong, count, self);
+
+        // If we decided that we need to push work, push either to the process or to a thread if
+        // one is specified.
+        if let Some(node) = push {
+            if let Some(thread) = othread {
+                thread.push_work_deferred(node);
+            } else {
+                let _ = self.push_work(node);
+                // Nothing to do: `push_work` may fail if the process is dead, but that's ok as in
+                // that case, it doesn't care about the notification.
+            }
+        }
+    }
+
+    pub(crate) fn new_node_ref(
+        &mut self,
+        node: DArc<Node>,
+        strong: bool,
+        thread: Option<&Thread>,
+    ) -> NodeRef {
+        self.update_node_refcount(&node, true, strong, 1, thread);
+        let strong_count = if strong { 1 } else { 0 };
+        NodeRef::new(node, strong_count, 1 - strong_count)
+    }
+
+    pub(crate) fn new_node_ref_with_thread(
+        &mut self,
+        node: DArc<Node>,
+        strong: bool,
+        thread: &Thread,
+        wrapper: Option<CritIncrWrapper>,
+    ) -> Result<NodeRef, CouldNotDeliverCriticalIncrement> {
+        let push = match wrapper {
+            None => node
+                .incr_refcount_allow_zero2one(strong, self)?
+                .map(|node| node as _),
+            Some(wrapper) => node.incr_refcount_allow_zero2one_with_wrapper(strong, wrapper, self),
+        };
+        if let Some(node) = push {
+            thread.push_work_deferred(node);
+        }
+        let strong_count = if strong { 1 } else { 0 };
+        Ok(NodeRef::new(node, strong_count, 1 - strong_count))
+    }
+
+    /// Returns an existing node with the given pointer and cookie, if one exists.
+    ///
+    /// Returns an error if a node with the given pointer but a different cookie exists.
+    fn get_existing_node(&self, ptr: u64, cookie: u64) -> Result<Option<DArc<Node>>> {
+        match self.nodes.get(&ptr) {
+            None => Ok(None),
+            Some(node) => {
+                let (_, node_cookie) = node.get_id();
+                if node_cookie == cookie {
+                    Ok(Some(node.clone()))
+                } else {
+                    Err(EINVAL)
+                }
+            }
+        }
+    }
+
+    fn register_thread(&mut self) -> bool {
+        if self.requested_thread_count == 0 {
+            return false;
+        }
+
+        self.requested_thread_count -= 1;
+        self.started_thread_count += 1;
+        true
+    }
+
+    /// Finds a delivered death notification with the given cookie, removes it from the thread's
+    /// delivered list, and returns it.
+    fn pull_delivered_death(&mut self, cookie: u64) -> Option<DArc<NodeDeath>> {
+        let mut cursor = self.delivered_deaths.cursor_front();
+        while let Some(next) = cursor.peek_next() {
+            if next.cookie == cookie {
+                return Some(next.remove().into_arc());
+            }
+            cursor.move_next();
+        }
+        None
+    }
+
+    pub(crate) fn death_delivered(&mut self, death: DArc<NodeDeath>) {
+        if let Some(death) = ListArc::try_from_arc_or_drop(death) {
+            self.delivered_deaths.push_back(death);
+        } else {
+            pr_warn!("Notification added to `delivered_deaths` twice.");
+        }
+    }
+
+    pub(crate) fn add_outstanding_txn(&mut self) {
+        self.outstanding_txns += 1;
+    }
+
+    fn txns_pending_locked(&self) -> bool {
+        if self.outstanding_txns > 0 {
+            return true;
+        }
+        for thread in self.threads.values() {
+            if thread.has_current_transaction() {
+                return true;
+            }
+        }
+        false
+    }
+}
+
+/// Used to keep track of a node that this process has a handle to.
+#[pin_data]
+pub(crate) struct NodeRefInfo {
+    debug_id: usize,
+    /// The refcount that this process owns to the node.
+    node_ref: ListArcField<NodeRef, { Self::LIST_PROC }>,
+    death: ListArcField<Option<DArc<NodeDeath>>, { Self::LIST_PROC }>,
+    /// Cookie of the active freeze listener for this node.
+    freeze: ListArcField<Option<FreezeCookie>, { Self::LIST_PROC }>,
+    /// Used to store this `NodeRefInfo` in the node's `refs` list.
+    #[pin]
+    links: ListLinks<{ Self::LIST_NODE }>,
+    /// The handle for this `NodeRefInfo`.
+    handle: u32,
+    /// The process that has a handle to the node.
+    pub(crate) process: Arc<Process>,
+}
+
+impl NodeRefInfo {
+    /// The id used for the `Node::refs` list.
+    pub(crate) const LIST_NODE: u64 = 0x2da16350fb724a10;
+    /// The id used for the `ListArc` in `ProcessNodeRefs`.
+    const LIST_PROC: u64 = 0xd703a5263dcc8650;
+
+    fn new(node_ref: NodeRef, handle: u32, process: Arc<Process>) -> impl PinInit<Self> {
+        pin_init!(Self {
+            debug_id: super::next_debug_id(),
+            node_ref: ListArcField::new(node_ref),
+            death: ListArcField::new(None),
+            freeze: ListArcField::new(None),
+            links <- ListLinks::new(),
+            handle,
+            process,
+        })
+    }
+
+    kernel::list::define_list_arc_field_getter! {
+        pub(crate) fn death(&mut self<{Self::LIST_PROC}>) -> &mut Option<DArc<NodeDeath>> { death }
+        pub(crate) fn freeze(&mut self<{Self::LIST_PROC}>) -> &mut Option<FreezeCookie> { freeze }
+        pub(crate) fn node_ref(&mut self<{Self::LIST_PROC}>) -> &mut NodeRef { node_ref }
+        pub(crate) fn node_ref2(&self<{Self::LIST_PROC}>) -> &NodeRef { node_ref }
+    }
+}
+
+kernel::list::impl_list_arc_safe! {
+    impl ListArcSafe<{Self::LIST_NODE}> for NodeRefInfo { untracked; }
+    impl ListArcSafe<{Self::LIST_PROC}> for NodeRefInfo { untracked; }
+}
+kernel::list::impl_list_item! {
+    impl ListItem<{Self::LIST_NODE}> for NodeRefInfo {
+        using ListLinks { self.links };
+    }
+}
+
+/// Keeps track of references this process has to nodes owned by other processes.
+///
+/// TODO: Currently, the rbtree requires two allocations per node reference, and two tree
+/// traversals to look up a node by `Node::global_id`. Once the rbtree is more powerful, these
+/// extra costs should be eliminated.
+struct ProcessNodeRefs {
+    /// Used to look up nodes using the 32-bit id that this process knows it by.
+    by_handle: RBTree<u32, ListArc<NodeRefInfo, { NodeRefInfo::LIST_PROC }>>,
+    /// Used to look up nodes without knowing their local 32-bit id. The usize is the address of
+    /// the underlying `Node` struct as returned by `Node::global_id`.
+    by_node: RBTree<usize, u32>,
+    /// Used to look up a `FreezeListener` by cookie.
+    ///
+    /// There might be multiple freeze listeners for the same node, but at most one of them is
+    /// active.
+    freeze_listeners: RBTree<FreezeCookie, FreezeListener>,
+}
+
+impl ProcessNodeRefs {
+    fn new() -> Self {
+        Self {
+            by_handle: RBTree::new(),
+            by_node: RBTree::new(),
+            freeze_listeners: RBTree::new(),
+        }
+    }
+}
+
+/// A process using binder.
+///
+/// Strictly speaking, there can be multiple of these per process. There is one for each binder fd
+/// that a process has opened, so processes using several binder contexts have several `Process`
+/// objects. This ensures that the contexts are fully separated.
+#[pin_data]
+pub(crate) struct Process {
+    pub(crate) ctx: Arc<Context>,
+
+    // The task leader (process).
+    pub(crate) task: ARef<Task>,
+
+    // Credential associated with file when `Process` is created.
+    pub(crate) cred: ARef<Credential>,
+
+    #[pin]
+    pub(crate) inner: SpinLock<ProcessInner>,
+
+    #[pin]
+    pub(crate) pages: ShrinkablePageRange,
+
+    // Waitqueue of processes waiting for all outstanding transactions to be
+    // processed.
+    #[pin]
+    freeze_wait: CondVar,
+
+    // Node references are in a different lock to avoid recursive acquisition when
+    // incrementing/decrementing a node in another process.
+    #[pin]
+    node_refs: Mutex<ProcessNodeRefs>,
+
+    // Work node for deferred work item.
+    #[pin]
+    defer_work: Work<Process>,
+
+    // Links for process list in Context.
+    #[pin]
+    links: ListLinks,
+
+    pub(crate) stats: BinderStats,
+}
+
+kernel::impl_has_work! {
+    impl HasWork<Process> for Process { self.defer_work }
+}
+
+kernel::list::impl_list_arc_safe! {
+    impl ListArcSafe<0> for Process { untracked; }
+}
+kernel::list::impl_list_item! {
+    impl ListItem<0> for Process {
+        using ListLinks { self.links };
+    }
+}
+
+impl workqueue::WorkItem for Process {
+    type Pointer = Arc<Process>;
+
+    fn run(me: Arc<Self>) {
+        let defer;
+        {
+            let mut inner = me.inner.lock();
+            defer = inner.defer_work;
+            inner.defer_work = 0;
+        }
+
+        if defer & PROC_DEFER_FLUSH != 0 {
+            me.deferred_flush();
+        }
+        if defer & PROC_DEFER_RELEASE != 0 {
+            me.deferred_release();
+        }
+    }
+}
+
+impl Process {
+    fn new(ctx: Arc<Context>, cred: ARef<Credential>) -> Result<Arc<Self>> {
+        let current = kernel::current!();
+        let list_process = ListArc::pin_init::<Error>(
+            try_pin_init!(Process {
+                ctx,
+                cred,
+                inner <- kernel::new_spinlock!(ProcessInner::new(), "Process::inner"),
+                pages <- ShrinkablePageRange::new(&super::BINDER_SHRINKER),
+                node_refs <- kernel::new_mutex!(ProcessNodeRefs::new(), "Process::node_refs"),
+                freeze_wait <- kernel::new_condvar!("Process::freeze_wait"),
+                task: current.group_leader().into(),
+                defer_work <- kernel::new_work!("Process::defer_work"),
+                links <- ListLinks::new(),
+                stats: BinderStats::new(),
+            }),
+            GFP_KERNEL,
+        )?;
+
+        let process = list_process.clone_arc();
+        process.ctx.register_process(list_process);
+
+        Ok(process)
+    }
+
+    pub(crate) fn pid_in_current_ns(&self) -> kernel::task::Pid {
+        self.task.tgid_nr_ns(None)
+    }
+
+    #[inline(never)]
+    pub(crate) fn debug_print_stats(&self, m: &SeqFile, ctx: &Context) -> Result<()> {
+        seq_print!(m, "proc {}\n", self.pid_in_current_ns());
+        seq_print!(m, "context {}\n", &*ctx.name);
+
+        let inner = self.inner.lock();
+        seq_print!(m, "  threads: {}\n", inner.threads.iter().count());
+        seq_print!(
+            m,
+            "  requested threads: {}+{}/{}\n",
+            inner.requested_thread_count,
+            inner.started_thread_count,
+            inner.max_threads,
+        );
+        if let Some(mapping) = &inner.mapping {
+            seq_print!(
+                m,
+                "  free oneway space: {}\n",
+                mapping.alloc.free_oneway_space()
+            );
+            seq_print!(m, "  buffers: {}\n", mapping.alloc.count_buffers());
+        }
+        seq_print!(
+            m,
+            "  outstanding transactions: {}\n",
+            inner.outstanding_txns
+        );
+        seq_print!(m, "  nodes: {}\n", inner.nodes.iter().count());
+        drop(inner);
+
+        {
+            let mut refs = self.node_refs.lock();
+            let (mut count, mut weak, mut strong) = (0, 0, 0);
+            for r in refs.by_handle.values_mut() {
+                let node_ref = r.node_ref();
+                let (nstrong, nweak) = node_ref.get_count();
+                count += 1;
+                weak += nweak;
+                strong += nstrong;
+            }
+            seq_print!(m, "  refs: {count} s {strong} w {weak}\n");
+        }
+
+        self.stats.debug_print("  ", m);
+
+        Ok(())
+    }
+
+    #[inline(never)]
+    pub(crate) fn debug_print(&self, m: &SeqFile, ctx: &Context, print_all: bool) -> Result<()> {
+        seq_print!(m, "proc {}\n", self.pid_in_current_ns());
+        seq_print!(m, "context {}\n", &*ctx.name);
+
+        let mut all_threads = KVec::new();
+        let mut all_nodes = KVec::new();
+        loop {
+            let inner = self.inner.lock();
+            let num_threads = inner.threads.iter().count();
+            let num_nodes = inner.nodes.iter().count();
+
+            if all_threads.capacity() < num_threads || all_nodes.capacity() < num_nodes {
+                drop(inner);
+                all_threads.reserve(num_threads, GFP_KERNEL)?;
+                all_nodes.reserve(num_nodes, GFP_KERNEL)?;
+                continue;
+            }
+
+            for thread in inner.threads.values() {
+                assert!(all_threads.len() < all_threads.capacity());
+                let _ = all_threads.push(thread.clone(), GFP_ATOMIC);
+            }
+
+            for node in inner.nodes.values() {
+                assert!(all_nodes.len() < all_nodes.capacity());
+                let _ = all_nodes.push(node.clone(), GFP_ATOMIC);
+            }
+
+            break;
+        }
+
+        for thread in all_threads {
+            thread.debug_print(m, print_all)?;
+        }
+
+        let mut inner = self.inner.lock();
+        for node in all_nodes {
+            if print_all || node.has_oneway_transaction(&mut inner) {
+                node.full_debug_print(m, &mut inner)?;
+            }
+        }
+        drop(inner);
+
+        if print_all {
+            let mut refs = self.node_refs.lock();
+            for r in refs.by_handle.values_mut() {
+                let node_ref = r.node_ref();
+                let dead = node_ref.node.owner.inner.lock().is_dead;
+                let (strong, weak) = node_ref.get_count();
+                let debug_id = node_ref.node.debug_id;
+
+                seq_print!(
+                    m,
+                    "  ref {}: desc {} {}node {debug_id} s {strong} w {weak}",
+                    r.debug_id,
+                    r.handle,
+                    if dead { "dead " } else { "" },
+                );
+            }
+        }
+
+        let inner = self.inner.lock();
+        for work in &inner.work {
+            work.debug_print(m, "  ", "  pending transaction ")?;
+        }
+        for _death in &inner.delivered_deaths {
+            seq_print!(m, "  has delivered dead binder\n");
+        }
+        if let Some(mapping) = &inner.mapping {
+            mapping.alloc.debug_print(m)?;
+        }
+        drop(inner);
+
+        Ok(())
+    }
+
+    /// Attempts to fetch a work item from the process queue.
+    pub(crate) fn get_work(&self) -> Option<DLArc<dyn DeliverToRead>> {
+        self.inner.lock().work.pop_front()
+    }
+
+    /// Attempts to fetch a work item from the process queue. If none is available, it registers the
+    /// given thread as ready to receive work directly.
+    ///
+    /// This must only be called when the thread is not participating in a transaction chain; when
+    /// it is, work will always be delivered directly to the thread (and not through the process
+    /// queue).
+    pub(crate) fn get_work_or_register<'a>(
+        &'a self,
+        thread: &'a Arc<Thread>,
+    ) -> GetWorkOrRegister<'a> {
+        let mut inner = self.inner.lock();
+        // Try to get work from the process queue.
+        if let Some(work) = inner.work.pop_front() {
+            return GetWorkOrRegister::Work(work);
+        }
+
+        // Register the thread as ready.
+        GetWorkOrRegister::Register(Registration::new(thread, &mut inner))
+    }
+
+    fn get_current_thread(self: ArcBorrow<'_, Self>) -> Result<Arc<Thread>> {
+        let id = {
+            let current = kernel::current!();
+            if !core::ptr::eq(current.group_leader(), &*self.task) {
+                pr_err!("get_current_thread was called from the wrong process.");
+                return Err(EINVAL);
+            }
+            current.pid()
+        };
+
+        {
+            let inner = self.inner.lock();
+            if let Some(thread) = inner.threads.get(&id) {
+                return Ok(thread.clone());
+            }
+        }
+
+        // Allocate a new `Thread` without holding any locks.
+        let reservation = RBTreeNodeReservation::new(GFP_KERNEL)?;
+        let ta: Arc<Thread> = Thread::new(id, self.into())?;
+
+        let mut inner = self.inner.lock();
+        match inner.threads.entry(id) {
+            rbtree::Entry::Vacant(entry) => {
+                entry.insert(ta.clone(), reservation);
+                Ok(ta)
+            }
+            rbtree::Entry::Occupied(_entry) => {
+                pr_err!("Cannot create two threads with the same id.");
+                Err(EINVAL)
+            }
+        }
+    }
+
+    pub(crate) fn push_work(&self, work: DLArc<dyn DeliverToRead>) -> BinderResult {
+        // If push_work fails, drop the work item outside the lock.
+        let res = self.inner.lock().push_work(work);
+        match res {
+            Ok(()) => Ok(()),
+            Err((err, work)) => {
+                drop(work);
+                Err(err)
+            }
+        }
+    }
+
+    fn set_as_manager(
+        self: ArcBorrow<'_, Self>,
+        info: Option<FlatBinderObject>,
+        thread: &Thread,
+    ) -> Result {
+        let (ptr, cookie, flags) = if let Some(obj) = info {
+            (
+                // SAFETY: The object type for this ioctl is implicitly `BINDER_TYPE_BINDER`, so it
+                // is safe to access the `binder` field.
+                unsafe { obj.__bindgen_anon_1.binder },
+                obj.cookie,
+                obj.flags,
+            )
+        } else {
+            (0, 0, 0)
+        };
+        let node_ref = self.get_node(ptr, cookie, flags as _, true, thread)?;
+        let node = node_ref.node.clone();
+        self.ctx.set_manager_node(node_ref)?;
+        self.inner.lock().is_manager = true;
+
+        // Force the state of the node to prevent the delivery of acquire/increfs.
+        let mut owner_inner = node.owner.inner.lock();
+        node.force_has_count(&mut owner_inner);
+        Ok(())
+    }
+
+    fn get_node_inner(
+        self: ArcBorrow<'_, Self>,
+        ptr: u64,
+        cookie: u64,
+        flags: u32,
+        strong: bool,
+        thread: &Thread,
+        wrapper: Option<CritIncrWrapper>,
+    ) -> Result<Result<NodeRef, CouldNotDeliverCriticalIncrement>> {
+        // Try to find an existing node.
+        {
+            let mut inner = self.inner.lock();
+            if let Some(node) = inner.get_existing_node(ptr, cookie)? {
+                return Ok(inner.new_node_ref_with_thread(node, strong, thread, wrapper));
+            }
+        }
+
+        // Allocate the node before reacquiring the lock.
+        let node = DTRWrap::arc_pin_init(Node::new(ptr, cookie, flags, self.into()))?.into_arc();
+        let rbnode = RBTreeNode::new(ptr, node.clone(), GFP_KERNEL)?;
+        let mut inner = self.inner.lock();
+        if let Some(node) = inner.get_existing_node(ptr, cookie)? {
+            return Ok(inner.new_node_ref_with_thread(node, strong, thread, wrapper));
+        }
+
+        inner.nodes.insert(rbnode);
+        // This can only fail if someone has already pushed the node to a list, but we just created
+        // it and still hold the lock, so it can't fail right now.
+        let node_ref = inner
+            .new_node_ref_with_thread(node, strong, thread, wrapper)
+            .unwrap();
+
+        Ok(Ok(node_ref))
+    }
+
+    pub(crate) fn get_node(
+        self: ArcBorrow<'_, Self>,
+        ptr: u64,
+        cookie: u64,
+        flags: u32,
+        strong: bool,
+        thread: &Thread,
+    ) -> Result<NodeRef> {
+        let mut wrapper = None;
+        for _ in 0..2 {
+            match self.get_node_inner(ptr, cookie, flags, strong, thread, wrapper) {
+                Err(err) => return Err(err),
+                Ok(Ok(node_ref)) => return Ok(node_ref),
+                Ok(Err(CouldNotDeliverCriticalIncrement)) => {
+                    wrapper = Some(CritIncrWrapper::new()?);
+                }
+            }
+        }
+        // We only get a `CouldNotDeliverCriticalIncrement` error if `wrapper` is `None`, so the
+        // loop should run at most twice.
+        unreachable!()
+    }
+
+    pub(crate) fn insert_or_update_handle(
+        self: ArcBorrow<'_, Process>,
+        node_ref: NodeRef,
+        is_mananger: bool,
+    ) -> Result<u32> {
+        {
+            let mut refs = self.node_refs.lock();
+
+            // Do a lookup before inserting.
+            if let Some(handle_ref) = refs.by_node.get(&node_ref.node.global_id()) {
+                let handle = *handle_ref;
+                let info = refs.by_handle.get_mut(&handle).unwrap();
+                info.node_ref().absorb(node_ref);
+                return Ok(handle);
+            }
+        }
+
+        // Reserve memory for tree nodes.
+        let reserve1 = RBTreeNodeReservation::new(GFP_KERNEL)?;
+        let reserve2 = RBTreeNodeReservation::new(GFP_KERNEL)?;
+        let info = UniqueArc::new_uninit(GFP_KERNEL)?;
+
+        let mut refs = self.node_refs.lock();
+
+        // Do a lookup again as node may have been inserted before the lock was reacquired.
+        if let Some(handle_ref) = refs.by_node.get(&node_ref.node.global_id()) {
+            let handle = *handle_ref;
+            let info = refs.by_handle.get_mut(&handle).unwrap();
+            info.node_ref().absorb(node_ref);
+            return Ok(handle);
+        }
+
+        // Find id.
+        let mut target: u32 = if is_mananger { 0 } else { 1 };
+        for handle in refs.by_handle.keys() {
+            if *handle > target {
+                break;
+            }
+            if *handle == target {
+                target = target.checked_add(1).ok_or(ENOMEM)?;
+            }
+        }
+
+        let gid = node_ref.node.global_id();
+        let (info_proc, info_node) = {
+            let info_init = NodeRefInfo::new(node_ref, target, self.into());
+            match info.pin_init_with(info_init) {
+                Ok(info) => ListArc::pair_from_pin_unique(info),
+                // error is infallible
+                Err(err) => match err {},
+            }
+        };
+
+        // Ensure the process is still alive while we insert a new reference.
+        //
+        // This releases the lock before inserting the nodes, but since `is_dead` is set as the
+        // first thing in `deferred_release`, process cleanup will not miss the items inserted into
+        // `refs` below.
+        if self.inner.lock().is_dead {
+            return Err(ESRCH);
+        }
+
+        // SAFETY: `info_proc` and `info_node` reference the same node, so we are inserting
+        // `info_node` into the right node's `refs` list.
+        unsafe { info_proc.node_ref2().node.insert_node_info(info_node) };
+
+        refs.by_node.insert(reserve1.into_node(gid, target));
+        refs.by_handle.insert(reserve2.into_node(target, info_proc));
+        Ok(target)
+    }
+
+    pub(crate) fn get_transaction_node(&self, handle: u32) -> BinderResult<NodeRef> {
+        // When handle is zero, try to get the context manager.
+        if handle == 0 {
+            Ok(self.ctx.get_manager_node(true)?)
+        } else {
+            Ok(self.get_node_from_handle(handle, true)?)
+        }
+    }
+
+    pub(crate) fn get_node_from_handle(&self, handle: u32, strong: bool) -> Result<NodeRef> {
+        self.node_refs
+            .lock()
+            .by_handle
+            .get_mut(&handle)
+            .ok_or(ENOENT)?
+            .node_ref()
+            .clone(strong)
+    }
+
+    pub(crate) fn remove_from_delivered_deaths(&self, death: &DArc<NodeDeath>) {
+        let mut inner = self.inner.lock();
+        // SAFETY: By the invariant on the `delivered_links` field, this is the right linked list.
+        let removed = unsafe { inner.delivered_deaths.remove(death) };
+        drop(inner);
+        drop(removed);
+    }
+
+    pub(crate) fn update_ref(
+        self: ArcBorrow<'_, Process>,
+        handle: u32,
+        inc: bool,
+        strong: bool,
+    ) -> Result {
+        if inc && handle == 0 {
+            if let Ok(node_ref) = self.ctx.get_manager_node(strong) {
+                if core::ptr::eq(&*self, &*node_ref.node.owner) {
+                    return Err(EINVAL);
+                }
+                let _ = self.insert_or_update_handle(node_ref, true);
+                return Ok(());
+            }
+        }
+
+        // To preserve original binder behaviour, we only fail requests where the manager tries to
+        // increment references on itself.
+        let mut refs = self.node_refs.lock();
+        if let Some(info) = refs.by_handle.get_mut(&handle) {
+            if info.node_ref().update(inc, strong) {
+                // Clean up death if there is one attached to this node reference.
+                if let Some(death) = info.death().take() {
+                    death.set_cleared(true);
+                    self.remove_from_delivered_deaths(&death);
+                }
+
+                // Remove reference from process tables, and from the node's `refs` list.
+
+                // SAFETY: We are removing the `NodeRefInfo` from the right node.
+                unsafe { info.node_ref2().node.remove_node_info(info) };
+
+                let id = info.node_ref().node.global_id();
+                refs.by_handle.remove(&handle);
+                refs.by_node.remove(&id);
+            }
+        } else {
+            // All refs are cleared in process exit, so this warning is expected in that case.
+            if !self.inner.lock().is_dead {
+                pr_warn!("{}: no such ref {handle}\n", self.pid_in_current_ns());
+            }
+        }
+        Ok(())
+    }
+
+    /// Decrements the refcount of the given node, if one exists.
+    pub(crate) fn update_node(&self, ptr: u64, cookie: u64, strong: bool) {
+        let mut inner = self.inner.lock();
+        if let Ok(Some(node)) = inner.get_existing_node(ptr, cookie) {
+            inner.update_node_refcount(&node, false, strong, 1, None);
+        }
+    }
+
+    pub(crate) fn inc_ref_done(&self, reader: &mut UserSliceReader, strong: bool) -> Result {
+        let ptr = reader.read::<u64>()?;
+        let cookie = reader.read::<u64>()?;
+        let mut inner = self.inner.lock();
+        if let Ok(Some(node)) = inner.get_existing_node(ptr, cookie) {
+            if let Some(node) = node.inc_ref_done_locked(strong, &mut inner) {
+                // This only fails if the process is dead.
+                let _ = inner.push_work(node);
+            }
+        }
+        Ok(())
+    }
+
+    pub(crate) fn buffer_alloc(
+        self: &Arc<Self>,
+        debug_id: usize,
+        size: usize,
+        is_oneway: bool,
+        from_pid: i32,
+    ) -> BinderResult<NewAllocation> {
+        use kernel::page::PAGE_SIZE;
+
+        let mut reserve_new_args = ReserveNewArgs {
+            debug_id,
+            size,
+            is_oneway,
+            pid: from_pid,
+            ..ReserveNewArgs::default()
+        };
+
+        let (new_alloc, addr) = loop {
+            let mut inner = self.inner.lock();
+            let mapping = inner.mapping.as_mut().ok_or_else(BinderError::new_dead)?;
+            let alloc_request = match mapping.alloc.reserve_new(reserve_new_args)? {
+                ReserveNew::Success(new_alloc) => break (new_alloc, mapping.address),
+                ReserveNew::NeedAlloc(request) => request,
+            };
+            drop(inner);
+            // We need to allocate memory and then call `reserve_new` again.
+            reserve_new_args = alloc_request.make_alloc()?;
+        };
+
+        let res = Allocation::new(
+            self.clone(),
+            debug_id,
+            new_alloc.offset,
+            size,
+            addr + new_alloc.offset,
+            new_alloc.oneway_spam_detected,
+        );
+
+        // This allocation will be marked as in use until the `Allocation` is used to free it.
+        //
+        // This method can't be called while holding a lock, so we release the lock first. It's
+        // okay for several threads to use the method on the same index at the same time. In that
+        // case, one of the calls will allocate the given page (if missing), and the other call
+        // will wait for the other call to finish allocating the page.
+        //
+        // We will not call `stop_using_range` in parallel with this on the same page, because the
+        // allocation can only be removed via the destructor of the `Allocation` object that we
+        // currently own.
+        match self.pages.use_range(
+            new_alloc.offset / PAGE_SIZE,
+            (new_alloc.offset + size).div_ceil(PAGE_SIZE),
+        ) {
+            Ok(()) => {}
+            Err(err) => {
+                pr_warn!("use_range failure {:?}", err);
+                return Err(err.into());
+            }
+        }
+
+        Ok(NewAllocation(res))
+    }
+
+    pub(crate) fn buffer_get(self: &Arc<Self>, ptr: usize) -> Option<Allocation> {
+        let mut inner = self.inner.lock();
+        let mapping = inner.mapping.as_mut()?;
+        let offset = ptr.checked_sub(mapping.address)?;
+        let (size, debug_id, odata) = mapping.alloc.reserve_existing(offset).ok()?;
+        let mut alloc = Allocation::new(self.clone(), debug_id, offset, size, ptr, false);
+        if let Some(data) = odata {
+            alloc.set_info(data);
+        }
+        Some(alloc)
+    }
+
+    pub(crate) fn buffer_raw_free(&self, ptr: usize) {
+        let mut inner = self.inner.lock();
+        if let Some(ref mut mapping) = &mut inner.mapping {
+            let offset = match ptr.checked_sub(mapping.address) {
+                Some(offset) => offset,
+                None => return,
+            };
+
+            let freed_range = match mapping.alloc.reservation_abort(offset) {
+                Ok(freed_range) => freed_range,
+                Err(_) => {
+                    pr_warn!(
+                        "Pointer {:x} failed to free, base = {:x}\n",
+                        ptr,
+                        mapping.address
+                    );
+                    return;
+                }
+            };
+
+            // No more allocations in this range. Mark them as not in use.
+            //
+            // Must be done before we release the lock so that `use_range` is not used on these
+            // indices until `stop_using_range` returns.
+            self.pages
+                .stop_using_range(freed_range.start_page_idx, freed_range.end_page_idx);
+        }
+    }
+
+    pub(crate) fn buffer_make_freeable(&self, offset: usize, mut data: Option<AllocationInfo>) {
+        let mut inner = self.inner.lock();
+        if let Some(ref mut mapping) = &mut inner.mapping {
+            if mapping.alloc.reservation_commit(offset, &mut data).is_err() {
+                pr_warn!("Offset {} failed to be marked freeable\n", offset);
+            }
+        }
+    }
+
+    fn create_mapping(&self, vma: &mm::virt::VmaNew) -> Result {
+        use kernel::page::PAGE_SIZE;
+        let size = usize::min(vma.end() - vma.start(), bindings::SZ_4M as usize);
+        let mapping = Mapping::new(vma.start(), size);
+        let page_count = self.pages.register_with_vma(vma)?;
+        if page_count * PAGE_SIZE != size {
+            return Err(EINVAL);
+        }
+
+        // Save range allocator for later.
+        self.inner.lock().mapping = Some(mapping);
+
+        Ok(())
+    }
+
+    fn version(&self, data: UserSlice) -> Result {
+        data.writer().write(&BinderVersion::current())
+    }
+
+    pub(crate) fn register_thread(&self) -> bool {
+        self.inner.lock().register_thread()
+    }
+
+    fn remove_thread(&self, thread: Arc<Thread>) {
+        self.inner.lock().threads.remove(&thread.id);
+        thread.release();
+    }
+
+    fn set_max_threads(&self, max: u32) {
+        self.inner.lock().max_threads = max;
+    }
+
+    fn set_oneway_spam_detection_enabled(&self, enabled: u32) {
+        self.inner.lock().oneway_spam_detection_enabled = enabled != 0;
+    }
+
+    pub(crate) fn is_oneway_spam_detection_enabled(&self) -> bool {
+        self.inner.lock().oneway_spam_detection_enabled
+    }
+
+    fn get_node_debug_info(&self, data: UserSlice) -> Result {
+        let (mut reader, mut writer) = data.reader_writer();
+
+        // Read the starting point.
+        let ptr = reader.read::<BinderNodeDebugInfo>()?.ptr;
+        let mut out = BinderNodeDebugInfo::default();
+
+        {
+            let inner = self.inner.lock();
+            for (node_ptr, node) in &inner.nodes {
+                if *node_ptr > ptr {
+                    node.populate_debug_info(&mut out, &inner);
+                    break;
+                }
+            }
+        }
+
+        writer.write(&out)
+    }
+
+    fn get_node_info_from_ref(&self, data: UserSlice) -> Result {
+        let (mut reader, mut writer) = data.reader_writer();
+        let mut out = reader.read::<BinderNodeInfoForRef>()?;
+
+        if out.strong_count != 0
+            || out.weak_count != 0
+            || out.reserved1 != 0
+            || out.reserved2 != 0
+            || out.reserved3 != 0
+        {
+            return Err(EINVAL);
+        }
+
+        // Only the context manager is allowed to use this ioctl.
+        if !self.inner.lock().is_manager {
+            return Err(EPERM);
+        }
+
+        {
+            let mut node_refs = self.node_refs.lock();
+            let node_info = node_refs.by_handle.get_mut(&out.handle).ok_or(ENOENT)?;
+            let node_ref = node_info.node_ref();
+            let owner_inner = node_ref.node.owner.inner.lock();
+            node_ref.node.populate_counts(&mut out, &owner_inner);
+        }
+
+        // Write the result back.
+        writer.write(&out)
+    }
+
+    pub(crate) fn needs_thread(&self) -> bool {
+        let mut inner = self.inner.lock();
+        let ret = inner.requested_thread_count == 0
+            && inner.ready_threads.is_empty()
+            && inner.started_thread_count < inner.max_threads;
+        if ret {
+            inner.requested_thread_count += 1
+        }
+        ret
+    }
+
+    pub(crate) fn request_death(
+        self: &Arc<Self>,
+        reader: &mut UserSliceReader,
+        thread: &Thread,
+    ) -> Result {
+        let handle: u32 = reader.read()?;
+        let cookie: u64 = reader.read()?;
+
+        // Queue BR_ERROR if we can't allocate memory for the death notification.
+        let death = UniqueArc::new_uninit(GFP_KERNEL).inspect_err(|_| {
+            thread.push_return_work(BR_ERROR);
+        })?;
+        let mut refs = self.node_refs.lock();
+        let Some(info) = refs.by_handle.get_mut(&handle) else {
+            pr_warn!("BC_REQUEST_DEATH_NOTIFICATION invalid ref {handle}\n");
+            return Ok(());
+        };
+
+        // Nothing to do if there is already a death notification request for this handle.
+        if info.death().is_some() {
+            pr_warn!("BC_REQUEST_DEATH_NOTIFICATION death notification already set\n");
+            return Ok(());
+        }
+
+        let death = {
+            let death_init = NodeDeath::new(info.node_ref().node.clone(), self.clone(), cookie);
+            match death.pin_init_with(death_init) {
+                Ok(death) => death,
+                // error is infallible
+                Err(err) => match err {},
+            }
+        };
+
+        // Register the death notification.
+        {
+            let owner = info.node_ref2().node.owner.clone();
+            let mut owner_inner = owner.inner.lock();
+            if owner_inner.is_dead {
+                let death = Arc::from(death);
+                *info.death() = Some(death.clone());
+                drop(owner_inner);
+                death.set_dead();
+            } else {
+                let death = ListArc::from(death);
+                *info.death() = Some(death.clone_arc());
+                info.node_ref().node.add_death(death, &mut owner_inner);
+            }
+        }
+        Ok(())
+    }
+
+    pub(crate) fn clear_death(&self, reader: &mut UserSliceReader, thread: &Thread) -> Result {
+        let handle: u32 = reader.read()?;
+        let cookie: u64 = reader.read()?;
+
+        let mut refs = self.node_refs.lock();
+        let Some(info) = refs.by_handle.get_mut(&handle) else {
+            pr_warn!("BC_CLEAR_DEATH_NOTIFICATION invalid ref {handle}\n");
+            return Ok(());
+        };
+
+        let Some(death) = info.death().take() else {
+            pr_warn!("BC_CLEAR_DEATH_NOTIFICATION death notification not active\n");
+            return Ok(());
+        };
+        if death.cookie != cookie {
+            *info.death() = Some(death);
+            pr_warn!("BC_CLEAR_DEATH_NOTIFICATION death notification cookie mismatch\n");
+            return Ok(());
+        }
+
+        // Update state and determine if we need to queue a work item. We only need to do it when
+        // the node is not dead or if the user already completed the death notification.
+        if death.set_cleared(false) {
+            if let Some(death) = ListArc::try_from_arc_or_drop(death) {
+                let _ = thread.push_work_if_looper(death);
+            }
+        }
+
+        Ok(())
+    }
+
+    pub(crate) fn dead_binder_done(&self, cookie: u64, thread: &Thread) {
+        if let Some(death) = self.inner.lock().pull_delivered_death(cookie) {
+            death.set_notification_done(thread);
+        }
+    }
+
+    /// Locks the spinlock and move the `nodes` rbtree out.
+    ///
+    /// This allows you to iterate through `nodes` while also allowing you to give other parts of
+    /// the codebase exclusive access to `ProcessInner`.
+    pub(crate) fn lock_with_nodes(&self) -> WithNodes<'_> {
+        let mut inner = self.inner.lock();
+        WithNodes {
+            nodes: take(&mut inner.nodes),
+            inner,
+        }
+    }
+
+    fn deferred_flush(&self) {
+        let inner = self.inner.lock();
+        for thread in inner.threads.values() {
+            thread.exit_looper();
+        }
+    }
+
+    fn deferred_release(self: Arc<Self>) {
+        let is_manager = {
+            let mut inner = self.inner.lock();
+            inner.is_dead = true;
+            inner.is_frozen = false;
+            inner.sync_recv = false;
+            inner.async_recv = false;
+            inner.is_manager
+        };
+
+        if is_manager {
+            self.ctx.unset_manager_node();
+        }
+
+        self.ctx.deregister_process(&self);
+
+        let binderfs_file = self.inner.lock().binderfs_file.take();
+        drop(binderfs_file);
+
+        // Release threads.
+        let threads = {
+            let mut inner = self.inner.lock();
+            let threads = take(&mut inner.threads);
+            let ready = take(&mut inner.ready_threads);
+            drop(inner);
+            drop(ready);
+
+            for thread in threads.values() {
+                thread.release();
+            }
+            threads
+        };
+
+        // Release nodes.
+        {
+            while let Some(node) = {
+                let mut lock = self.inner.lock();
+                lock.nodes.cursor_front().map(|c| c.remove_current().1)
+            } {
+                node.to_key_value().1.release();
+            }
+        }
+
+        // Clean up death listeners and remove nodes from external node info lists.
+        for info in self.node_refs.lock().by_handle.values_mut() {
+            // SAFETY: We are removing the `NodeRefInfo` from the right node.
+            unsafe { info.node_ref2().node.remove_node_info(info) };
+
+            // Remove all death notifications from the nodes (that belong to a different process).
+            let death = if let Some(existing) = info.death().take() {
+                existing
+            } else {
+                continue;
+            };
+            death.set_cleared(false);
+        }
+
+        // Clean up freeze listeners.
+        let freeze_listeners = take(&mut self.node_refs.lock().freeze_listeners);
+        for listener in freeze_listeners.values() {
+            listener.on_process_exit(&self);
+        }
+        drop(freeze_listeners);
+
+        // Release refs on foreign nodes.
+        {
+            let mut refs = self.node_refs.lock();
+            let by_handle = take(&mut refs.by_handle);
+            let by_node = take(&mut refs.by_node);
+            drop(refs);
+            drop(by_node);
+            drop(by_handle);
+        }
+
+        // Cancel all pending work items.
+        while let Some(work) = self.get_work() {
+            work.into_arc().cancel();
+        }
+
+        let delivered_deaths = take(&mut self.inner.lock().delivered_deaths);
+        drop(delivered_deaths);
+
+        // Free any resources kept alive by allocated buffers.
+        let omapping = self.inner.lock().mapping.take();
+        if let Some(mut mapping) = omapping {
+            let address = mapping.address;
+            mapping
+                .alloc
+                .take_for_each(|offset, size, debug_id, odata| {
+                    let ptr = offset + address;
+                    pr_warn!(
+                        "{}: removing orphan mapping {offset}:{size}\n",
+                        self.pid_in_current_ns()
+                    );
+                    let mut alloc =
+                        Allocation::new(self.clone(), debug_id, offset, size, ptr, false);
+                    if let Some(data) = odata {
+                        alloc.set_info(data);
+                    }
+                    drop(alloc)
+                });
+        }
+
+        // calls to synchronize_rcu() in thread drop will happen here
+        drop(threads);
+    }
+
+    pub(crate) fn drop_outstanding_txn(&self) {
+        let wake = {
+            let mut inner = self.inner.lock();
+            if inner.outstanding_txns == 0 {
+                pr_err!("outstanding_txns underflow");
+                return;
+            }
+            inner.outstanding_txns -= 1;
+            inner.is_frozen && inner.outstanding_txns == 0
+        };
+
+        if wake {
+            self.freeze_wait.notify_all();
+        }
+    }
+
+    pub(crate) fn ioctl_freeze(&self, info: &BinderFreezeInfo) -> Result {
+        if info.enable == 0 {
+            let msgs = self.prepare_freeze_messages()?;
+            let mut inner = self.inner.lock();
+            inner.sync_recv = false;
+            inner.async_recv = false;
+            inner.is_frozen = false;
+            drop(inner);
+            msgs.send_messages();
+            return Ok(());
+        }
+
+        let mut inner = self.inner.lock();
+        inner.sync_recv = false;
+        inner.async_recv = false;
+        inner.is_frozen = true;
+
+        if info.timeout_ms > 0 {
+            let mut jiffies = kernel::time::msecs_to_jiffies(info.timeout_ms);
+            while jiffies > 0 {
+                if inner.outstanding_txns == 0 {
+                    break;
+                }
+
+                match self
+                    .freeze_wait
+                    .wait_interruptible_timeout(&mut inner, jiffies)
+                {
+                    CondVarTimeoutResult::Signal { .. } => {
+                        inner.is_frozen = false;
+                        return Err(ERESTARTSYS);
+                    }
+                    CondVarTimeoutResult::Woken { jiffies: remaining } => {
+                        jiffies = remaining;
+                    }
+                    CondVarTimeoutResult::Timeout => {
+                        jiffies = 0;
+                    }
+                }
+            }
+        }
+
+        if inner.txns_pending_locked() {
+            inner.is_frozen = false;
+            Err(EAGAIN)
+        } else {
+            drop(inner);
+            match self.prepare_freeze_messages() {
+                Ok(batch) => {
+                    batch.send_messages();
+                    Ok(())
+                }
+                Err(kernel::alloc::AllocError) => {
+                    self.inner.lock().is_frozen = false;
+                    Err(ENOMEM)
+                }
+            }
+        }
+    }
+}
+
+fn get_frozen_status(data: UserSlice) -> Result {
+    let (mut reader, mut writer) = data.reader_writer();
+
+    let mut info = reader.read::<BinderFrozenStatusInfo>()?;
+    info.sync_recv = 0;
+    info.async_recv = 0;
+    let mut found = false;
+
+    for ctx in crate::context::get_all_contexts()? {
+        ctx.for_each_proc(|proc| {
+            if proc.task.pid() == info.pid as _ {
+                found = true;
+                let inner = proc.inner.lock();
+                let txns_pending = inner.txns_pending_locked();
+                info.async_recv |= inner.async_recv as u32;
+                info.sync_recv |= inner.sync_recv as u32;
+                info.sync_recv |= (txns_pending as u32) << 1;
+            }
+        });
+    }
+
+    if found {
+        writer.write(&info)?;
+        Ok(())
+    } else {
+        Err(EINVAL)
+    }
+}
+
+fn ioctl_freeze(reader: &mut UserSliceReader) -> Result {
+    let info = reader.read::<BinderFreezeInfo>()?;
+
+    // Very unlikely for there to be more than 3, since a process normally uses at most binder and
+    // hwbinder.
+    let mut procs = KVec::with_capacity(3, GFP_KERNEL)?;
+
+    let ctxs = crate::context::get_all_contexts()?;
+    for ctx in ctxs {
+        for proc in ctx.get_procs_with_pid(info.pid as i32)? {
+            procs.push(proc, GFP_KERNEL)?;
+        }
+    }
+
+    for proc in procs {
+        proc.ioctl_freeze(&info)?;
+    }
+    Ok(())
+}
+
+/// The ioctl handler.
+impl Process {
+    /// Ioctls that are write-only from the perspective of userspace.
+    ///
+    /// The kernel will only read from the pointer that userspace provided to us.
+    fn ioctl_write_only(
+        this: ArcBorrow<'_, Process>,
+        _file: &File,
+        cmd: u32,
+        reader: &mut UserSliceReader,
+    ) -> Result {
+        let thread = this.get_current_thread()?;
+        match cmd {
+            uapi::BINDER_SET_MAX_THREADS => this.set_max_threads(reader.read()?),
+            uapi::BINDER_THREAD_EXIT => this.remove_thread(thread),
+            uapi::BINDER_SET_CONTEXT_MGR => this.set_as_manager(None, &thread)?,
+            uapi::BINDER_SET_CONTEXT_MGR_EXT => {
+                this.set_as_manager(Some(reader.read()?), &thread)?
+            }
+            uapi::BINDER_ENABLE_ONEWAY_SPAM_DETECTION => {
+                this.set_oneway_spam_detection_enabled(reader.read()?)
+            }
+            uapi::BINDER_FREEZE => ioctl_freeze(reader)?,
+            _ => return Err(EINVAL),
+        }
+        Ok(())
+    }
+
+    /// Ioctls that are read/write from the perspective of userspace.
+    ///
+    /// The kernel will both read from and write to the pointer that userspace provided to us.
+    fn ioctl_write_read(
+        this: ArcBorrow<'_, Process>,
+        file: &File,
+        cmd: u32,
+        data: UserSlice,
+    ) -> Result {
+        let thread = this.get_current_thread()?;
+        let blocking = (file.flags() & file::flags::O_NONBLOCK) == 0;
+        match cmd {
+            uapi::BINDER_WRITE_READ => thread.write_read(data, blocking)?,
+            uapi::BINDER_GET_NODE_DEBUG_INFO => this.get_node_debug_info(data)?,
+            uapi::BINDER_GET_NODE_INFO_FOR_REF => this.get_node_info_from_ref(data)?,
+            uapi::BINDER_VERSION => this.version(data)?,
+            uapi::BINDER_GET_FROZEN_INFO => get_frozen_status(data)?,
+            uapi::BINDER_GET_EXTENDED_ERROR => thread.get_extended_error(data)?,
+            _ => return Err(EINVAL),
+        }
+        Ok(())
+    }
+}
+
+/// The file operations supported by `Process`.
+impl Process {
+    pub(crate) fn open(ctx: ArcBorrow<'_, Context>, file: &File) -> Result<Arc<Process>> {
+        Self::new(ctx.into(), ARef::from(file.cred()))
+    }
+
+    pub(crate) fn release(this: Arc<Process>, _file: &File) {
+        let binderfs_file;
+        let should_schedule;
+        {
+            let mut inner = this.inner.lock();
+            should_schedule = inner.defer_work == 0;
+            inner.defer_work |= PROC_DEFER_RELEASE;
+            binderfs_file = inner.binderfs_file.take();
+        }
+
+        if should_schedule {
+            // Ignore failures to schedule to the workqueue. Those just mean that we're already
+            // scheduled for execution.
+            let _ = workqueue::system().enqueue(this);
+        }
+
+        drop(binderfs_file);
+    }
+
+    pub(crate) fn flush(this: ArcBorrow<'_, Process>) -> Result {
+        let should_schedule;
+        {
+            let mut inner = this.inner.lock();
+            should_schedule = inner.defer_work == 0;
+            inner.defer_work |= PROC_DEFER_FLUSH;
+        }
+
+        if should_schedule {
+            // Ignore failures to schedule to the workqueue. Those just mean that we're already
+            // scheduled for execution.
+            let _ = workqueue::system().enqueue(Arc::from(this));
+        }
+        Ok(())
+    }
+
+    pub(crate) fn ioctl(this: ArcBorrow<'_, Process>, file: &File, cmd: u32, arg: usize) -> Result {
+        use kernel::ioctl::{_IOC_DIR, _IOC_SIZE};
+        use kernel::uapi::{_IOC_READ, _IOC_WRITE};
+
+        crate::trace::trace_ioctl(cmd, arg);
+
+        let user_slice = UserSlice::new(UserPtr::from_addr(arg), _IOC_SIZE(cmd));
+
+        const _IOC_READ_WRITE: u32 = _IOC_READ | _IOC_WRITE;
+
+        match _IOC_DIR(cmd) {
+            _IOC_WRITE => Self::ioctl_write_only(this, file, cmd, &mut user_slice.reader()),
+            _IOC_READ_WRITE => Self::ioctl_write_read(this, file, cmd, user_slice),
+            _ => Err(EINVAL),
+        }
+    }
+
+    pub(crate) fn compat_ioctl(
+        this: ArcBorrow<'_, Process>,
+        file: &File,
+        cmd: u32,
+        arg: usize,
+    ) -> Result {
+        Self::ioctl(this, file, cmd, arg)
+    }
+
+    pub(crate) fn mmap(
+        this: ArcBorrow<'_, Process>,
+        _file: &File,
+        vma: &mm::virt::VmaNew,
+    ) -> Result {
+        // We don't allow mmap to be used in a different process.
+        if !core::ptr::eq(kernel::current!().group_leader(), &*this.task) {
+            return Err(EINVAL);
+        }
+        if vma.start() == 0 {
+            return Err(EINVAL);
+        }
+
+        vma.try_clear_maywrite().map_err(|_| EPERM)?;
+        vma.set_dontcopy();
+        vma.set_mixedmap();
+
+        // TODO: Set ops. We need to learn when the user unmaps so that we can stop using it.
+        this.create_mapping(vma)
+    }
+
+    pub(crate) fn poll(
+        this: ArcBorrow<'_, Process>,
+        file: &File,
+        table: PollTable<'_>,
+    ) -> Result<u32> {
+        let thread = this.get_current_thread()?;
+        let (from_proc, mut mask) = thread.poll(file, table);
+        if mask == 0 && from_proc && !this.inner.lock().work.is_empty() {
+            mask |= bindings::POLLIN;
+        }
+        Ok(mask)
+    }
+}
+
+/// Represents that a thread has registered with the `ready_threads` list of its process.
+///
+/// The destructor of this type will unregister the thread from the list of ready threads.
+pub(crate) struct Registration<'a> {
+    thread: &'a Arc<Thread>,
+}
+
+impl<'a> Registration<'a> {
+    fn new(thread: &'a Arc<Thread>, guard: &mut Guard<'_, ProcessInner, SpinLockBackend>) -> Self {
+        assert!(core::ptr::eq(&thread.process.inner, guard.lock_ref()));
+        // INVARIANT: We are pushing this thread to the right `ready_threads` list.
+        if let Ok(list_arc) = ListArc::try_from_arc(thread.clone()) {
+            guard.ready_threads.push_front(list_arc);
+        } else {
+            // It is an error to hit this branch, and it should not be reachable. We try to do
+            // something reasonable when the failure path happens. Most likely, the thread in
+            // question will sleep forever.
+            pr_err!("Same thread registered with `ready_threads` twice.");
+        }
+        Self { thread }
+    }
+}
+
+impl Drop for Registration<'_> {
+    fn drop(&mut self) {
+        let mut inner = self.thread.process.inner.lock();
+        // SAFETY: The thread has the invariant that we never push it to any other linked list than
+        // the `ready_threads` list of its parent process. Therefore, the thread is either in that
+        // list, or in no list.
+        unsafe { inner.ready_threads.remove(self.thread) };
+    }
+}
+
+pub(crate) struct WithNodes<'a> {
+    pub(crate) inner: Guard<'a, ProcessInner, SpinLockBackend>,
+    pub(crate) nodes: RBTree<u64, DArc<Node>>,
+}
+
+impl Drop for WithNodes<'_> {
+    fn drop(&mut self) {
+        core::mem::swap(&mut self.nodes, &mut self.inner.nodes);
+        if self.nodes.iter().next().is_some() {
+            pr_err!("nodes array was modified while using lock_with_nodes\n");
+        }
+    }
+}
+
+pub(crate) enum GetWorkOrRegister<'a> {
+    Work(DLArc<dyn DeliverToRead>),
+    Register(Registration<'a>),
+}