Struct Page

pub struct Page { /* private fields */ }

A pointer to a page that owns the page allocation.

Invariants

The pointer is valid, and has ownership over the page.

Implementations

impl Page

pub fn alloc_page(flags: Flags) -> Result<Self, AllocError>

Allocates a new page.

Examples

Allocate memory for a page.

use kernel::page::Page;

let page = Page::alloc_page(GFP_KERNEL)?;

Allocate memory for a page and zero its contents.

use kernel::page::Page;

let page = Page::alloc_page(GFP_KERNEL | __GFP_ZERO)?;

pub fn as_ptr(&self) -> *mut page

Returns a raw pointer to the page.

pub unsafe fn read_raw(&self, dst: *mut u8, offset: usize, len: usize) -> Result

Maps the page and reads from it into the given buffer.

This method will perform bounds checks on the page offset. If offset .. offset+len goes outside of the page, then this call returns EINVAL.

Safety

• Callers must ensure that dst is valid for writing len bytes.
• Callers must ensure that this call does not race with a write to the same page that overlaps with this read.

pub unsafe fn write_raw( &self, src: *const u8, offset: usize, len: usize, ) -> Result

Maps the page and writes into it from the given buffer.

This method will perform bounds checks on the page offset. If offset .. offset+len goes outside of the page, then this call returns EINVAL.

Safety

• Callers must ensure that src is valid for reading len bytes.
• Callers must ensure that this call does not race with a read or write to the same page that overlaps with this write.

pub unsafe fn fill_zero_raw(&self, offset: usize, len: usize) -> Result

Maps the page and zeroes the given slice.

This method will perform bounds checks on the page offset. If offset .. offset+len goes outside of the page, then this call returns EINVAL.

Safety

Callers must ensure that this call does not race with a read or write to the same page that overlaps with this write.

pub unsafe fn copy_from_user_slice_raw( &self, reader: &mut UserSliceReader, offset: usize, len: usize, ) -> Result

Copies data from userspace into this page.

This method will perform bounds checks on the page offset. If offset .. offset+len goes outside of the page, then this call returns EINVAL.

Like the other UserSliceReader methods, data races are allowed on the userspace address. However, they are not allowed on the page you are copying into.

Safety

Callers must ensure that this call does not race with a read or write to the same page that overlaps with this write.

Trait Implementations

impl Drop for Page

fn drop(&mut self)

Executes the destructor for this type.

impl Send for Page

impl Sync for Page