Switch page_manager to use frame_allocator.

Removed the frame allocation logic from page_manager and replaced it
with using an instance of frame_allocator instead. This had several
major ripple effects:

- memory_initalize() had to change to support this new world
  - Where to map used blocks is now passed as a flag, since blocks don't
    track their virtual address anymore
  - Instead of the complicated "find N contiguous pages that can be
    mapped in with one page table", we now just have the bootloader give
    us some (currently 64) pages to use both for tables and scratch
    space.
  - frame_allocator initialization was split into two steps to allow
    mapping used blocks before std::move()ing them over

src/libraries/kutil/frame_allocator.cpp

@@ -53,14 +53,18 @@ frame_block::copy(frame_block *other)
 
 
 frame_allocator::frame_allocator(
-	frame_block_list free,
-	frame_block_list used,
 	frame_block_list cache)
+{
+	m_block_slab.append(cache);
+}
+
+void
+frame_allocator::init(
+	frame_block_list free,
+	frame_block_list used)
 {
 	m_free.append(free);
 	m_used.append(used);
-	m_block_slab.append(cache);
-
 	consolidate_blocks();
 }
 

src/libraries/kutil/include/kutil/frame_allocator.h

@@ -21,14 +21,19 @@ public:
 	/// Size of a single page frame.
 	static const size_t frame_size = 0x1000;
 
-	/// Constructor. Sets up the frame allocator from bootstraped memory.
+	/// Default constructor
+	frame_allocator() = default;
+
+	/// Constructor with a provided initial frame_block cache.
+	/// \arg cache  List of pre-allocated but unused frame_block structures
+	frame_allocator(frame_block_list cache);
+
+	/// Initialize the frame allocator from bootstraped memory.
 	/// \arg free   List of free blocks
 	/// \arg used   List of currently used blocks
-	/// \arg cache  List of pre-allocated but unused frame_block structures
-	frame_allocator(
+	void init(
 			frame_block_list free,
-			frame_block_list used,
-			frame_block_list cache);
+			frame_block_list used);
 
 	/// Get free frames from the free list. Only frames from the first free block
 	/// are returned, so the number may be less than requested, but they will
@@ -59,14 +64,22 @@ private:
 /// Flags used by `frame_block`.
 enum class frame_block_flags : uint32_t
 {
-	none         = 0x00,
+	none         = 0x0000,
 
-	mmio         = 0x01,  ///< Memory is a MMIO region
-	nonvolatile  = 0x02,  ///< Memory is non-volatile storage
+	mmio         = 0x0001,  ///< Memory is a MMIO region
+	nonvolatile  = 0x0002,  ///< Memory is non-volatile storage
 
-	pending_free = 0x10,  ///< Memory should be freed
-	acpi_wait    = 0x40,  ///< Memory should be freed after ACPI init
-	permanent    = 0x80   ///< Memory is permanently unusable
+	pending_free = 0x0020,  ///< Memory should be freed
+	acpi_wait    = 0x0040,  ///< Memory should be freed after ACPI init
+	permanent    = 0x0080,  ///< Memory is permanently unusable
+
+	// The following are used only during the memory bootstraping
+	// process, and tell the page manager where to initially map
+	// the given block.
+	map_ident    = 0x0100,  ///< Identity map
+	map_kernel   = 0x0200,  ///< Map into normal kernel space
+	map_offset   = 0x0400,  ///< Map into offset kernel space
+	map_mask     = 0x0700,  ///< Mask of all map_* values
 };
 
 } // namespace kutil