MmapRaw: Add some functions to catch up with MmapMut.

src/lib.rs

@@ -800,6 +800,30 @@ impl MmapRaw {
     pub fn flush_async_range(&self, offset: usize, len: usize) -> Result<()> {
         self.inner.flush_async(offset, len)
     }
+
+    /// Advise OS how this memory map will be accessed. Only supported on Unix.
+    ///
+    /// See [madvise()](https://man7.org/linux/man-pages/man2/madvise.2.html) map page.
+    #[cfg(unix)]
+    pub fn advise(&self, advice: Advice) -> Result<()> {
+        self.inner.advise(advice)
+    }
+
+    /// Lock the whole memory map into RAM. Only supported on Unix.
+    ///
+    /// See [mlock()](https://man7.org/linux/man-pages/man2/mlock.2.html) map page.
+    #[cfg(unix)]
+    pub fn lock(&mut self) -> Result<()> {
+        self.inner.lock()
+    }
+
+    /// Unlock the whole memory map. Only supported on Unix.
+    ///
+    /// See [munlock()](https://man7.org/linux/man-pages/man2/munlock.2.html) map page.
+    #[cfg(unix)]
+    pub fn unlock(&mut self) -> Result<()> {
+        self.inner.unlock()
+    }
 }
 
 impl fmt::Debug for MmapRaw {