Struct MmWithUser

pub struct MmWithUser { /* private fields */ }

A wrapper for the kernel’s struct mm_struct.

This type is like Mm, but with non-zero mm_users. It can only be used when mm_users can be proven to be non-zero at compile-time, usually because the relevant code holds an mmget refcount. It can be used to access the associated address space.

The ARef<MmWithUser> smart pointer holds an mmget refcount. Its destructor may sleep.

Invariants

Values of this type are always refcounted using mmget. The value of mm_users is non-zero.

Implementations

impl MmWithUser

pub unsafe fn from_raw<'a>(ptr: *const mm_struct) -> &'a MmWithUser

Obtain a reference from a raw pointer.

Safety

The caller must ensure that ptr points at an mm_struct, and that mm_users remains non-zero for the duration of the lifetime ’a.

pub fn into_mmput_async(me: ARef<MmWithUser>) -> ARef<MmWithUserAsync>

Use mmput_async when dropping this refcount.

pub fn lock_vma_under_rcu(&self, vma_addr: usize) -> Option<VmaReadGuard<'_>>

Attempt to access a vma using the vma read lock.

This is an optimistic trylock operation, so it may fail if there is contention. In that case, you should fall back to taking the mmap read lock.

When per-vma locks are disabled, this always returns None.

pub fn mmap_read_lock(&self) -> MmapReadGuard<'_>

Lock the mmap read lock.

pub fn mmap_read_trylock(&self) -> Option<MmapReadGuard<'_>>

Try to lock the mmap read lock.

Methods from Deref<Target = Mm>

pub fn as_raw(&self) -> *mut mm_struct

Returns a raw pointer to the inner mm_struct.

pub fn mmget_not_zero(&self) -> Option<ARef<MmWithUser>>

Calls mmget_not_zero and returns a handle if it succeeds.

Trait Implementations

impl AlwaysRefCounted for MmWithUser

fn inc_ref(&self)

Increments the reference count on the object.

unsafe fn dec_ref(obj: NonNull<Self>)

Decrements the reference count on the object.

impl Deref for MmWithUser

type Target = Mm

The resulting type after dereferencing.

fn deref(&self) -> &Mm

Dereferences the value.

impl Send for MmWithUser

impl Sync for MmWithUser