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<ol class="chapter"><li class="chapter-item expanded affix "><a href="index.html">简明 zCore 教程</a></li><li class="chapter-item expanded affix "><a href="zcore-intro.html">🚧 zCore 整体结构和设计模式</a></li><li class="chapter-item expanded affix "><a href="fuchsia.html">🚧 Fuchsia OS 和 Zircon 微内核</a></li><li class="chapter-item expanded "><a href="ch01-00-object.html"><strong aria-hidden="true">1.</strong> 内核对象</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="ch01-01-kernel-object.html"><strong aria-hidden="true">1.1.</strong> ✅ 初识内核对象</a></li><li class="chapter-item expanded "><a href="ch01-02-process-object.html"><strong aria-hidden="true">1.2.</strong> 🚧 对象管理器：Process 对象</a></li><li class="chapter-item expanded "><a href="ch01-03-channel-object.html"><strong aria-hidden="true">1.3.</strong> 🚧 对象传送器：Channel 对象</a></li></ol></li><li class="chapter-item expanded "><a href="ch02-00-task.html"><strong aria-hidden="true">2.</strong> 任务管理</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="ch02-01-zircon-task.html"><strong aria-hidden="true">2.1.</strong> 🚧 Zircon 任务管理体系</a></li><li class="chapter-item expanded "><a href="ch02-02-process-job-object.html"><strong aria-hidden="true">2.2.</strong> 🚧 进程管理：Process 与 Job 对象</a></li><li class="chapter-item expanded "><a href="ch02-03-thread-object.html"><strong aria-hidden="true">2.3.</strong> 🚧 线程管理：Thread 对象</a></li></ol></li><li class="chapter-item expanded "><a href="ch03-00-memory.html"><strong aria-hidden="true">3.</strong> 内存管理</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="ch03-01-zircon-memory.html"><strong aria-hidden="true">3.1.</strong> 🚧 Zircon 内存管理模型</a></li><li class="chapter-item expanded "><a href="ch03-02-vmo.html"><strong aria-hidden="true">3.2.</strong> 🚧 物理内存：VMO 对象</a></li><li class="chapter-item expanded "><a href="ch03-03-vmo-paged.html" class="active"><strong aria-hidden="true">3.3.</strong> 🚧 物理内存：按页分配的 VMO</a></li><li class="chapter-item expanded "><a href="ch03-04-vmar.html"><strong aria-hidden="true">3.4.</strong> 🚧 虚拟内存：VMAR 对象</a></li></ol></li><li class="chapter-item expanded "><a href="ch04-00-userspace.html"><strong aria-hidden="true">4.</strong> 用户程序</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="ch04-01-user-program.html"><strong aria-hidden="true">4.1.</strong> 🚧 Zircon 用户程序</a></li><li class="chapter-item expanded "><a href="ch04-02-context-switch.html"><strong aria-hidden="true">4.2.</strong> 🚧 上下文切换</a></li><li class="chapter-item expanded "><a href="ch04-03-syscall.html"><strong aria-hidden="true">4.3.</strong> 🚧 系统调用</a></li></ol></li><li class="chapter-item expanded "><a href="ch05-00-signal-and-waiting.html"><strong aria-hidden="true">5.</strong> 信号和等待</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="ch05-01-wait-signal.html"><strong aria-hidden="true">5.1.</strong> 🚧 等待内核对象的信号</a></li><li class="chapter-item expanded "><a href="ch05-02-port-object.html"><strong aria-hidden="true">5.2.</strong> 🚧 同时等待多个信号：Port 对象</a></li><li class="chapter-item expanded "><a href="ch05-03-more-signal-objects.html"><strong aria-hidden="true">5.3.</strong> 🚧 实现更多：EventPair, Timer 对象</a></li><li class="chapter-item expanded "><a href="ch05-04-futex-object.html"><strong aria-hidden="true">5.4.</strong> 🚧 用户态同步互斥：Futex 对象</a></li></ol></li><li class="chapter-item expanded "><a href="ch06-00-hal.html"><strong aria-hidden="true">6.</strong> 硬件抽象层</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="ch06-01-zcore-hal-unix.html"><strong aria-hidden="true">6.1.</strong> ✅ UNIX硬件抽象层</a></li></ol></li></ol> </div>
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<main>
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<h1 id="物理内存按页分配的-vmo"><a class="header" href="#物理内存按页分配的-vmo">物理内存：按页分配的 VMO</a></h1>
|
|
|
<h2 id="简介"><a class="header" href="#简介">简介</a></h2>
|
|
|
<blockquote>
|
|
|
<p>说明一下：Zircon 的官方实现中为了高效支持写时复制，使用了复杂精巧的树状数据结构，但它同时也引入了复杂性和各种 Bug。
|
|
|
我们在这里只实现一个简单版本，完整实现留给读者自行探索。</p>
|
|
|
<p>介绍 commit 操作的意义和作用</p>
|
|
|
</blockquote>
|
|
|
<p>commit_page 和 commit_pages_with 函数的作用：用于检查物理页帧是否已经分配。</p>
|
|
|
<h2 id="hal物理内存管理"><a class="header" href="#hal物理内存管理">HAL：物理内存管理</a></h2>
|
|
|
<blockquote>
|
|
|
<p>在 HAL 中实现 PhysFrame 和最简单的分配器</p>
|
|
|
</blockquote>
|
|
|
<h3 id="kernel-hal"><a class="header" href="#kernel-hal">kernel-hal</a></h3>
|
|
|
<pre><pre class="playground"><code class="language-rust edition2018">
|
|
|
<span class="boring">#![allow(unused)]
|
|
|
</span><span class="boring">fn main() {
|
|
|
</span>#[repr(C)]
|
|
|
pub struct PhysFrame {
|
|
|
// paddr 物理地址
|
|
|
paddr: PhysAddr,
|
|
|
}
|
|
|
|
|
|
impl PhysFrame {
|
|
|
// 分配物理页帧
|
|
|
#[linkage = "weak"]
|
|
|
#[export_name = "hal_frame_alloc"]
|
|
|
pub fn alloc() -> Option<Self> {
|
|
|
unimplemented!()
|
|
|
}
|
|
|
|
|
|
#[linkage = "weak"]
|
|
|
#[export_name = "hal_frame_alloc_contiguous"]
|
|
|
pub fn alloc_contiguous_base(_size: usize, _align_log2: usize) -> Option<PhysAddr> {
|
|
|
unimplemented!()
|
|
|
}
|
|
|
|
|
|
pub fn alloc_contiguous(size: usize, align_log2: usize) -> Vec<Self> {
|
|
|
PhysFrame::alloc_contiguous_base(size, align_log2).map_or(Vec::new(), |base| {
|
|
|
(0..size)
|
|
|
.map(|i| PhysFrame {
|
|
|
paddr: base + i * PAGE_SIZE,
|
|
|
})
|
|
|
.collect()
|
|
|
})
|
|
|
}
|
|
|
|
|
|
pub fn alloc_zeroed() -> Option<Self> {
|
|
|
Self::alloc().map(|f| {
|
|
|
pmem_zero(f.addr(), PAGE_SIZE);
|
|
|
f
|
|
|
})
|
|
|
}
|
|
|
|
|
|
pub fn alloc_contiguous_zeroed(size: usize, align_log2: usize) -> Vec<Self> {
|
|
|
PhysFrame::alloc_contiguous_base(size, align_log2).map_or(Vec::new(), |base| {
|
|
|
pmem_zero(base, size * PAGE_SIZE);
|
|
|
(0..size)
|
|
|
.map(|i| PhysFrame {
|
|
|
paddr: base + i * PAGE_SIZE,
|
|
|
})
|
|
|
.collect()
|
|
|
})
|
|
|
}
|
|
|
|
|
|
pub fn addr(&self) -> PhysAddr {
|
|
|
self.paddr
|
|
|
}
|
|
|
|
|
|
#[linkage = "weak"]
|
|
|
#[export_name = "hal_zero_frame_paddr"]
|
|
|
pub fn zero_frame_addr() -> PhysAddr {
|
|
|
unimplemented!()
|
|
|
}
|
|
|
}
|
|
|
|
|
|
impl Drop for PhysFrame {
|
|
|
#[linkage = "weak"]
|
|
|
#[export_name = "hal_frame_dealloc"]
|
|
|
fn drop(&mut self) {
|
|
|
unimplemented!()
|
|
|
}
|
|
|
}
|
|
|
<span class="boring">}
|
|
|
</span></code></pre></pre>
|
|
|
<h3 id="kernel-hal-unix"><a class="header" href="#kernel-hal-unix">kernel-hal-unix</a></h3>
|
|
|
<p>通过下面的代码可以构造一个页帧号。<code>(PAGE_SIZE..PMEM_SIZE).step_by(PAGE_SIZE).collect()</code> 可以每隔 PAGE_SIZE 生成一个页帧的开始位置。</p>
|
|
|
<pre><pre class="playground"><code class="language-rust edition2018">
|
|
|
<span class="boring">#![allow(unused)]
|
|
|
</span><span class="boring">fn main() {
|
|
|
</span>lazy_static! {
|
|
|
static ref AVAILABLE_FRAMES: Mutex<VecDeque<usize>> =
|
|
|
Mutex::new((PAGE_SIZE..PMEM_SIZE).step_by(PAGE_SIZE).collect());
|
|
|
}
|
|
|
<span class="boring">}
|
|
|
</span></code></pre></pre>
|
|
|
<p>分配一块物理页帧就是从 AVAILABLE_FRAMES 中通过 pop_front 弹出一个页号</p>
|
|
|
<pre><pre class="playground"><code class="language-rust edition2018">
|
|
|
<span class="boring">#![allow(unused)]
|
|
|
</span><span class="boring">fn main() {
|
|
|
</span>impl PhysFrame {
|
|
|
#[export_name = "hal_frame_alloc"]
|
|
|
pub fn alloc() -> Option<Self> {
|
|
|
let ret = AVAILABLE_FRAMES
|
|
|
.lock()
|
|
|
.unwrap()
|
|
|
.pop_front()
|
|
|
.map(|paddr| PhysFrame { paddr });
|
|
|
trace!("frame alloc: {:?}", ret);
|
|
|
ret
|
|
|
}
|
|
|
#[export_name = "hal_zero_frame_paddr"]
|
|
|
pub fn zero_frame_addr() -> PhysAddr {
|
|
|
0
|
|
|
}
|
|
|
}
|
|
|
|
|
|
impl Drop for PhysFrame {
|
|
|
#[export_name = "hal_frame_dealloc"]
|
|
|
fn drop(&mut self) {
|
|
|
trace!("frame dealloc: {:?}", self);
|
|
|
AVAILABLE_FRAMES.lock().unwrap().push_back(self.paddr);
|
|
|
}
|
|
|
}
|
|
|
<span class="boring">}
|
|
|
</span></code></pre></pre>
|
|
|
<h2 id="辅助结构blockrange-迭代器"><a class="header" href="#辅助结构blockrange-迭代器">辅助结构：BlockRange 迭代器</a></h2>
|
|
|
<blockquote>
|
|
|
<p>实现 BlockRange</p>
|
|
|
</blockquote>
|
|
|
<p>在按页分配内存的 VMObjectPaged 的读和写的方法中会使用到一个 BlockIter 迭代器。BlockIter 主要用于将一段内存分块，每次返回这一块的信息也就是 BlockRange。</p>
|
|
|
<h3 id="blockiter"><a class="header" href="#blockiter">BlockIter</a></h3>
|
|
|
<pre><pre class="playground"><code class="language-rust edition2018">
|
|
|
<span class="boring">#![allow(unused)]
|
|
|
</span><span class="boring">fn main() {
|
|
|
</span>#[derive(Debug, Eq, PartialEq)]
|
|
|
pub struct BlockRange {
|
|
|
pub block: usize,
|
|
|
pub begin: usize, // 块内地址开始位置
|
|
|
pub end: usize, // 块内地址结束位置
|
|
|
pub block_size_log2: u8,
|
|
|
}
|
|
|
|
|
|
/// Given a range and iterate sub-range for each block
|
|
|
pub struct BlockIter {
|
|
|
pub begin: usize,
|
|
|
pub end: usize,
|
|
|
pub block_size_log2: u8,
|
|
|
}
|
|
|
<span class="boring">}
|
|
|
</span></code></pre></pre>
|
|
|
<p>block_size_log2 是 log 以2为底 block size, 比如：block size 大小为4096，则 block_size_log2 为 12。block 是块编号。</p>
|
|
|
<pre><pre class="playground"><code class="language-rust edition2018">
|
|
|
<span class="boring">#![allow(unused)]
|
|
|
</span><span class="boring">fn main() {
|
|
|
</span>impl BlockRange {
|
|
|
pub fn len(&self) -> usize {
|
|
|
self.end - self.begin
|
|
|
}
|
|
|
pub fn is_full(&self) -> bool {
|
|
|
self.len() == (1usize << self.block_size_log2)
|
|
|
}
|
|
|
pub fn is_empty(&self) -> bool {
|
|
|
self.len() == 0
|
|
|
}
|
|
|
pub fn origin_begin(&self) -> usize {
|
|
|
(self.block << self.block_size_log2) + self.begin
|
|
|
}
|
|
|
pub fn origin_end(&self) -> usize {
|
|
|
(self.block << self.block_size_log2) + self.end
|
|
|
}
|
|
|
}
|
|
|
|
|
|
impl Iterator for BlockIter {
|
|
|
type Item = BlockRange;
|
|
|
|
|
|
fn next(&mut self) -> Option<<Self as Iterator>::Item> {
|
|
|
if self.begin >= self.end {
|
|
|
return None;
|
|
|
}
|
|
|
let block_size_log2 = self.block_size_log2;
|
|
|
let block_size = 1usize << self.block_size_log2;
|
|
|
let block = self.begin / block_size;
|
|
|
let begin = self.begin % block_size;
|
|
|
// 只有最后一块需要计算块内最后的地址，其他的直接返回块的大小
|
|
|
let end = if block == self.end / block_size {
|
|
|
self.end % block_size
|
|
|
} else {
|
|
|
block_size
|
|
|
};
|
|
|
self.begin += end - begin;
|
|
|
Some(BlockRange {
|
|
|
block,
|
|
|
begin,
|
|
|
end,
|
|
|
block_size_log2,
|
|
|
})
|
|
|
}
|
|
|
}
|
|
|
<span class="boring">}
|
|
|
</span></code></pre></pre>
|
|
|
<h2 id="实现按页分配的-vmo"><a class="header" href="#实现按页分配的-vmo">实现按页分配的 VMO</a></h2>
|
|
|
<blockquote>
|
|
|
<p>实现 for_each_page, commit, read, write 函数</p>
|
|
|
</blockquote>
|
|
|
<p>按页分配的 VMO 结构体如下：</p>
|
|
|
<pre><pre class="playground"><code class="language-rust edition2018">
|
|
|
<span class="boring">#![allow(unused)]
|
|
|
</span><span class="boring">fn main() {
|
|
|
</span>pub struct VMObjectPaged {
|
|
|
inner: Mutex<VMObjectPagedInner>,
|
|
|
}
|
|
|
|
|
|
/// The mutable part of `VMObjectPaged`.
|
|
|
#[derive(Default)]
|
|
|
struct VMObjectPagedInner {
|
|
|
/// Physical frames of this VMO.
|
|
|
frames: Vec<PhysFrame>,
|
|
|
/// Cache Policy
|
|
|
cache_policy: CachePolicy,
|
|
|
/// Is contiguous
|
|
|
contiguous: bool,
|
|
|
/// Sum of pin_count
|
|
|
pin_count: usize,
|
|
|
/// All mappings to this VMO.
|
|
|
mappings: Vec<Weak<VmMapping>>,
|
|
|
}
|
|
|
<span class="boring">}
|
|
|
</span></code></pre></pre>
|
|
|
<p>VMObjectPage 有两个 new 方法</p>
|
|
|
<pre><pre class="playground"><code class="language-rust edition2018">
|
|
|
<span class="boring">#![allow(unused)]
|
|
|
</span><span class="boring">fn main() {
|
|
|
</span>impl VMObjectPaged {
|
|
|
/// Create a new VMO backing on physical memory allocated in pages.
|
|
|
pub fn new(pages: usize) -> Arc<Self> {
|
|
|
let mut frames = Vec::new();
|
|
|
frames.resize_with(pages, || PhysFrame::alloc_zeroed().unwrap()); // 分配 pages 个页帧号，并将这些页帧号的内存清零
|
|
|
Arc::new(VMObjectPaged {
|
|
|
inner: Mutex::new(VMObjectPagedInner {
|
|
|
frames,
|
|
|
..Default::default()
|
|
|
}),
|
|
|
})
|
|
|
}
|
|
|
|
|
|
/// Create a list of contiguous pages
|
|
|
pub fn new_contiguous(pages: usize, align_log2: usize) -> ZxResult<Arc<Self>> {
|
|
|
let frames = PhysFrame::alloc_contiguous_zeroed(pages, align_log2 - PAGE_SIZE_LOG2);
|
|
|
if frames.is_empty() {
|
|
|
return Err(ZxError::NO_MEMORY);
|
|
|
}
|
|
|
Ok(Arc::new(VMObjectPaged {
|
|
|
inner: Mutex::new(VMObjectPagedInner {
|
|
|
frames,
|
|
|
contiguous: true,
|
|
|
..Default::default()
|
|
|
}),
|
|
|
}))
|
|
|
}
|
|
|
}
|
|
|
<span class="boring">}
|
|
|
</span></code></pre></pre>
|
|
|
<p>VMObjectPaged 的读和写用到了一个非常重要的函数 for_each_page 。首先它先构造了一个 BlockIter 迭代器，然后调用传入的函数进行读或者写。</p>
|
|
|
<pre><pre class="playground"><code class="language-rust edition2018">
|
|
|
<span class="boring">#![allow(unused)]
|
|
|
</span><span class="boring">fn main() {
|
|
|
</span>impl VMObjectPagedInner {
|
|
|
/// Helper function to split range into sub-ranges within pages.
|
|
|
///
|
|
|
/// ```text
|
|
|
/// VMO range:
|
|
|
/// |----|----|----|----|----|
|
|
|
///
|
|
|
/// buf:
|
|
|
/// [====len====]
|
|
|
/// |--offset--|
|
|
|
///
|
|
|
/// sub-ranges:
|
|
|
/// [===]
|
|
|
/// [====]
|
|
|
/// [==]
|
|
|
/// ```
|
|
|
///
|
|
|
/// `f` is a function to process in-page ranges.
|
|
|
/// It takes 2 arguments:
|
|
|
/// * `paddr`: the start physical address of the in-page range.
|
|
|
/// * `buf_range`: the range in view of the input buffer.
|
|
|
fn for_each_page(
|
|
|
&mut self,
|
|
|
offset: usize,
|
|
|
buf_len: usize,
|
|
|
mut f: impl FnMut(PhysAddr, Range<usize>),
|
|
|
) {
|
|
|
let iter = BlockIter {
|
|
|
begin: offset,
|
|
|
end: offset + buf_len,
|
|
|
block_size_log2: 12,
|
|
|
};
|
|
|
for block in iter {
|
|
|
// 获取这一块开始的物理地址
|
|
|
let paddr = self.frames[block.block].addr();
|
|
|
// 这块物理地址的范围
|
|
|
let buf_range = block.origin_begin() - offset..block.origin_end() - offset;
|
|
|
f(paddr + block.begin, buf_range);
|
|
|
}
|
|
|
}
|
|
|
}
|
|
|
<span class="boring">}
|
|
|
</span></code></pre></pre>
|
|
|
<p>read 和 write 函数，一个传入的是 <code>kernel_hal::pmem_read</code> ，另外一个是 <code>kernel_hal::pmem_write</code></p>
|
|
|
<pre><pre class="playground"><code class="language-rust edition2018">
|
|
|
<span class="boring">#![allow(unused)]
|
|
|
</span><span class="boring">fn main() {
|
|
|
</span>impl VMObjectTrait for VMObjectPaged {
|
|
|
fn read(&self, offset: usize, buf: &mut [u8]) -> ZxResult {
|
|
|
let mut inner = self.inner.lock();
|
|
|
if inner.cache_policy != CachePolicy::Cached {
|
|
|
return Err(ZxError::BAD_STATE);
|
|
|
}
|
|
|
inner.for_each_page(offset, buf.len(), |paddr, buf_range| {
|
|
|
kernel_hal::pmem_read(paddr, &mut buf[buf_range]);
|
|
|
});
|
|
|
Ok(())
|
|
|
}
|
|
|
|
|
|
fn write(&self, offset: usize, buf: &[u8]) -> ZxResult {
|
|
|
let mut inner = self.inner.lock();
|
|
|
if inner.cache_policy != CachePolicy::Cached {
|
|
|
return Err(ZxError::BAD_STATE);
|
|
|
}
|
|
|
inner.for_each_page(offset, buf.len(), |paddr, buf_range| {
|
|
|
kernel_hal::pmem_write(paddr, &buf[buf_range]);
|
|
|
});
|
|
|
Ok(())
|
|
|
}
|
|
|
}
|
|
|
<span class="boring">}
|
|
|
</span></code></pre></pre>
|
|
|
<p>commit 函数</p>
|
|
|
<pre><pre class="playground"><code class="language-rust edition2018">
|
|
|
<span class="boring">#![allow(unused)]
|
|
|
</span><span class="boring">fn main() {
|
|
|
</span>impl VMObjectTrait for VMObjectPaged {
|
|
|
fn commit_page(&self, page_idx: usize, _flags: MMUFlags) -> ZxResult<PhysAddr> {
|
|
|
let inner = self.inner.lock();
|
|
|
Ok(inner.frames[page_idx].addr())
|
|
|
}
|
|
|
|
|
|
fn commit_pages_with(
|
|
|
&self,
|
|
|
f: &mut dyn FnMut(&mut dyn FnMut(usize, MMUFlags) -> ZxResult<PhysAddr>) -> ZxResult,
|
|
|
) -> ZxResult {
|
|
|
let inner = self.inner.lock();
|
|
|
f(&mut |page_idx, _| Ok(inner.frames[page_idx].addr()))
|
|
|
}
|
|
|
}
|
|
|
<span class="boring">}
|
|
|
</span></code></pre></pre>
|
|
|
<h2 id="vmo-复制"><a class="header" href="#vmo-复制">VMO 复制</a></h2>
|
|
|
<blockquote>
|
|
|
<p>实现 create_child 函数</p>
|
|
|
</blockquote>
|
|
|
<p>create_child 是将原 VMObjectPaged 的内容拷贝一份</p>
|
|
|
<pre><pre class="playground"><code class="language-rust edition2018">
|
|
|
<span class="boring">#![allow(unused)]
|
|
|
</span><span class="boring">fn main() {
|
|
|
</span>// object/vm/vmo/paged.rs
|
|
|
|
|
|
impl VMObjectTrait for VMObjectPaged {
|
|
|
fn create_child(&self, offset: usize, len: usize) -> ZxResult<Arc<dyn VMObjectTrait>> {
|
|
|
assert!(page_aligned(offset));
|
|
|
assert!(page_aligned(len));
|
|
|
let mut inner = self.inner.lock();
|
|
|
let child = inner.create_child(offset, len)?;
|
|
|
Ok(child)
|
|
|
}
|
|
|
|
|
|
/// Create a snapshot child VMO.
|
|
|
fn create_child(&mut self, offset: usize, len: usize) -> ZxResult<Arc<VMObjectPaged>> {
|
|
|
// clone contiguous vmo is no longer permitted
|
|
|
// https://fuchsia.googlesource.com/fuchsia/+/e6b4c6751bbdc9ed2795e81b8211ea294f139a45
|
|
|
if self.contiguous {
|
|
|
return Err(ZxError::INVALID_ARGS);
|
|
|
}
|
|
|
if self.cache_policy != CachePolicy::Cached || self.pin_count != 0 {
|
|
|
return Err(ZxError::BAD_STATE);
|
|
|
}
|
|
|
let mut frames = Vec::with_capacity(pages(len));
|
|
|
for _ in 0..pages(len) {
|
|
|
frames.push(PhysFrame::alloc().ok_or(ZxError::NO_MEMORY)?);
|
|
|
}
|
|
|
for (i, frame) in frames.iter().enumerate() {
|
|
|
if let Some(src_frame) = self.frames.get(pages(offset) + i) {
|
|
|
kernel_hal::frame_copy(src_frame.addr(), frame.addr())
|
|
|
} else {
|
|
|
kernel_hal::pmem_zero(frame.addr(), PAGE_SIZE);
|
|
|
}
|
|
|
}
|
|
|
// create child VMO
|
|
|
let child = Arc::new(VMObjectPaged {
|
|
|
inner: Mutex::new(VMObjectPagedInner {
|
|
|
frames,
|
|
|
..Default::default()
|
|
|
}),
|
|
|
});
|
|
|
Ok(child)
|
|
|
}
|
|
|
}
|
|
|
|
|
|
// kernel-hal-unix/sr/lib.rs
|
|
|
|
|
|
/// Copy content of `src` frame to `target` frame
|
|
|
#[export_name = "hal_frame_copy"]
|
|
|
pub fn frame_copy(src: PhysAddr, target: PhysAddr) {
|
|
|
trace!("frame_copy: {:#x} <- {:#x}", target, src);
|
|
|
assert!(src + PAGE_SIZE <= PMEM_SIZE && target + PAGE_SIZE <= PMEM_SIZE);
|
|
|
ensure_mmap_pmem();
|
|
|
unsafe {
|
|
|
let buf = phys_to_virt(src) as *const u8;
|
|
|
buf.copy_to_nonoverlapping(phys_to_virt(target) as _, PAGE_SIZE);
|
|
|
}
|
|
|
}
|
|
|
|
|
|
/// Zero physical memory at `[paddr, paddr + len)`
|
|
|
#[export_name = "hal_pmem_zero"]
|
|
|
pub fn pmem_zero(paddr: PhysAddr, len: usize) {
|
|
|
trace!("pmem_zero: addr={:#x}, len={:#x}", paddr, len);
|
|
|
assert!(paddr + len <= PMEM_SIZE);
|
|
|
ensure_mmap_pmem();
|
|
|
unsafe {
|
|
|
core::ptr::write_bytes(phys_to_virt(paddr) as *mut u8, 0, len);
|
|
|
}
|
|
|
}
|
|
|
<span class="boring">}
|
|
|
</span></code></pre></pre>
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