From aa85dbb4f1ff00a60019ced140e9d7bf984d44c5 Mon Sep 17 00:00:00 2001
From: Philipp Oppermann <dev@phil-opp.com>
Date: Fri, 6 Mar 2020 14:38:22 +0100
Subject: [PATCH 1/2] Add a Mapper::map convenience function

---
 src/structures/paging/mapper/mod.rs | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/src/structures/paging/mapper/mod.rs b/src/structures/paging/mapper/mod.rs
index d1c73898c..53f126a90 100644
--- a/src/structures/paging/mapper/mod.rs
+++ b/src/structures/paging/mapper/mod.rs
@@ -321,6 +321,34 @@ pub trait Mapper<S: PageSize> {
     /// error otherwise.
     fn translate_page(&self, page: Page<S>) -> Result<PhysFrame<S>, TranslateError>;
 
+    /// Maps the given page to an unused frame obtained from the frame_allocator.
+    ///
+    /// This function allocates at least one physical frame from the given
+    /// frame allocator. It might also need additional physical frames to create
+    /// new page tables, which are also allocated from the `frame_allocator`
+    /// argument. At most four frames are required from the allocator in total.
+    ///
+    /// ## Safety
+    ///
+    /// This is a convencience function that invokes [`map_to`] internally, so
+    /// all safety requirements of it also apply for this function.
+    #[inline]
+    unsafe fn map<A>(
+        &mut self,
+        page: Page<S>,
+        flags: PageTableFlags,
+        frame_allocator: &mut A,
+    ) -> Result<MapperFlush<S>, MapToError<S>>
+    where
+        Self: Sized,
+        A: FrameAllocator<Size4KiB> + FrameAllocator<S>,
+    {
+        let frame = frame_allocator
+            .allocate_frame()
+            .ok_or(MapToError::FrameAllocationFailed)?;
+        self.map_to(page, frame, flags, frame_allocator)
+    }
+
     /// Maps the given frame to the virtual page with the same address.
     ///
     /// ## Safety

From 9c7ff09fd77030d72360d286af0353155abd0e85 Mon Sep 17 00:00:00 2001
From: Philipp Oppermann <dev@phil-opp.com>
Date: Fri, 6 Mar 2020 14:38:40 +0100
Subject: [PATCH 2/2] Improve docs for Mapper::identity_map

---
 src/structures/paging/mapper/mod.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/structures/paging/mapper/mod.rs b/src/structures/paging/mapper/mod.rs
index 53f126a90..564b35084 100644
--- a/src/structures/paging/mapper/mod.rs
+++ b/src/structures/paging/mapper/mod.rs
@@ -351,6 +351,10 @@ pub trait Mapper<S: PageSize> {
 
     /// Maps the given frame to the virtual page with the same address.
     ///
+    /// This function might need additional physical frames to create new page
+    /// tables. These frames are allocated from the `frame_allocator` argument.
+    /// At most three frames are required.
+    ///
     /// ## Safety
     ///
     /// This is a convencience function that invokes [`map_to`] internally, so