core: hle: kernel: KPageTable: Improve Un/MapPhysicalMemory.

- Improves the implementations of MapPhysicalMemory and UnmapPhysicalMemory to more closely reflect latest HOS.

src/common/page_table.h

@@ -27,6 +27,16 @@ enum class PageType : u8 {
  * mimics the way a real CPU page table works.
  */
 struct PageTable {
+    struct TraversalEntry {
+        u64 phys_addr{};
+        std::size_t block_size{};
+    };
+
+    struct TraversalContext {
+        u64 next_page{};
+        u64 next_offset{};
+    };
+
     /// Number of bits reserved for attribute tagging.
     /// This can be at most the guaranteed alignment of the pointers in the page table.
     static constexpr int ATTRIBUTE_BITS = 2;
@@ -89,6 +99,10 @@ struct PageTable {
     PageTable(PageTable&&) noexcept = default;
     PageTable& operator=(PageTable&&) noexcept = default;
 
+    bool BeginTraversal(TraversalEntry* out_entry, TraversalContext* out_context,
+                        u64 address) const;
+    bool ContinueTraversal(TraversalEntry* out_entry, TraversalContext* context) const;
+
     /**
      * Resizes the page table to be able to accommodate enough pages within
      * a given address space.
@@ -96,9 +110,9 @@ struct PageTable {
      * @param address_space_width_in_bits The address size width in bits.
      * @param page_size_in_bits           The page size in bits.
      */
-    void Resize(size_t address_space_width_in_bits, size_t page_size_in_bits);
+    void Resize(std::size_t address_space_width_in_bits, std::size_t page_size_in_bits);
 
-    size_t GetAddressSpaceBits() const {
+    std::size_t GetAddressSpaceBits() const {
         return current_address_space_width_in_bits;
     }
 
@@ -110,9 +124,11 @@ struct PageTable {
 
     VirtualBuffer<u64> backing_addr;
 
-    size_t current_address_space_width_in_bits;
+    std::size_t current_address_space_width_in_bits{};
 
-    u8* fastmem_arena;
+    u8* fastmem_arena{};
+
+    std::size_t page_size{};
 };
 
 } // namespace Common