From f98a45aefe3f59f6aeaadb3f1e8f82d8bc036bbf Mon Sep 17 00:00:00 2001
From: apio <blobs.trading@gmail.com>
Date: Sat, 10 Sep 2022 22:15:19 +0200
Subject: [PATCH] Updated InitRD to use virtual mappings

---
 kernel/include/init/InitRD.h |  4 +++-
 kernel/src/init/InitRD.cpp   | 22 ++++++++++++++++++----
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/kernel/include/init/InitRD.h b/kernel/include/init/InitRD.h
index e4275507..de7df06b 100644
--- a/kernel/include/init/InitRD.h
+++ b/kernel/include/init/InitRD.h
@@ -36,9 +36,11 @@ namespace InitRD
 
     int get_total_blocks();
     File get_file(TarHeader* header);
+    void free_file(File& file);
     TarHeader* get_block(int block_index);
     bool is_valid_header(TarHeader* header);
 
-    File find_file(const char* filename);
+    File open(const char* filename);
+    void close(File& f);
     void for_each(void (*callback)(File& file));
 }
\ No newline at end of file
diff --git a/kernel/src/init/InitRD.cpp b/kernel/src/init/InitRD.cpp
index b107fd3d..ca9cb7d4 100644
--- a/kernel/src/init/InitRD.cpp
+++ b/kernel/src/init/InitRD.cpp
@@ -1,6 +1,7 @@
 #include "init/InitRD.h"
 #include "bootboot.h"
 #include "io/Serial.h"
+#include "memory/KernelMemoryManager.h"
 #include "std/stdlib.h"
 #include <string.h>
 
@@ -31,7 +32,6 @@ InitRD::File InitRD::get_file(TarHeader* header)
     File result;
     result.size = 0;
     memcpy(result.name, header->name, 100);
-    result.addr = (void*)(header + TAR_BLOCKSIZE);
     int multiplier =
         1; // why they decided to store the size as an octal-encoded string instead of an integer is beyond me
     for (int i = 10; i >= 0; i--)
@@ -39,21 +39,28 @@ InitRD::File InitRD::get_file(TarHeader* header)
         result.size += (multiplier * (header->size[i] - 48));
         multiplier *= 8;
     }
+    result.addr = KernelMemoryManager::get_unaligned_mappings((void*)(header + TAR_BLOCKSIZE), result.size / 4096 + 1);
     result.size_in_blocks = result.size / TAR_BLOCKSIZE + 1;
     return result;
 }
 
-InitRD::File InitRD::find_file(const char* filename)
+void InitRD::free_file(File& file)
+{
+    KernelMemoryManager::release_unaligned_mappings(file.addr, file.size / 4096 + 1);
+}
+
+InitRD::File InitRD::open(const char* filename)
 {
     int block = 0;
     int total_blocks = get_total_blocks();
     while (block < total_blocks)
     {
-        TarHeader* hdr = get_block(block);
+        TarHeader* hdr = (TarHeader*)KernelMemoryManager::get_unaligned_mapping(get_block(block));
         block++;
         if (hdr->typeflag == 53) { continue; } // Directory
         if (!is_valid_header(hdr)) { continue; }
         auto f = get_file(hdr);
+        KernelMemoryManager::release_unaligned_mapping(hdr);
         if (strncmp(hdr->name, filename, strlen(filename)) == 0) { return f; }
         block += get_file_size_in_blocks(f);
     }
@@ -64,18 +71,25 @@ InitRD::File InitRD::find_file(const char* filename)
     return nullFile;
 }
 
+void InitRD::close(File& file)
+{
+    free_file(file);
+}
+
 void InitRD::for_each(void (*callback)(File& f))
 {
     int block = 0;
     int total_blocks = get_total_blocks();
     while (block < total_blocks)
     {
-        TarHeader* hdr = get_block(block);
+        TarHeader* hdr = (TarHeader*)KernelMemoryManager::get_unaligned_mapping(get_block(block));
         block++;
         if (hdr->typeflag == 53) { continue; } // Directory
         if (!is_valid_header(hdr)) { continue; }
         auto f = get_file(hdr);
         block += get_file_size_in_blocks(f);
+        KernelMemoryManager::release_unaligned_mapping(hdr);
         callback(f);
+        close(f);
     }
 }
\ No newline at end of file