From 30a48d25d2145757d5cf195e46b248d2ff07b3b0 Mon Sep 17 00:00:00 2001
From: Eggert Jung <eggert.s.jung@wischhof13.de>
Date: Mon, 12 Jan 2026 14:58:23 +0100
Subject: [PATCH] remove bitmap

---
 kernel/memory/pageframe.h       |  4 +++-
 kernel/memory/pageframealloc.cc | 32 ++++++++++++++++----------------
 kernel/memory/pageframealloc.h  |  1 +
 3 files changed, 20 insertions(+), 17 deletions(-)

diff --git a/kernel/memory/pageframe.h b/kernel/memory/pageframe.h
index 9b1eacf..8dd26c5 100644
--- a/kernel/memory/pageframe.h
+++ b/kernel/memory/pageframe.h
@@ -5,10 +5,12 @@
 
 class PageFrame {
     private:
+    public:
         uintptr_t address;
         uintptr_t mapped_address;
-    public:
+        bool available;
         PageFrame* queue_link;
+        PageFrame(){};
         PageFrame(uintptr_t a):address(a){};
         uintptr_t getAddr(){return address;};
         uintptr_t getVirtualAddr(){return address;};
diff --git a/kernel/memory/pageframealloc.cc b/kernel/memory/pageframealloc.cc
index ccb9099..1a0a05c 100644
--- a/kernel/memory/pageframealloc.cc
+++ b/kernel/memory/pageframealloc.cc
@@ -8,9 +8,8 @@
 #include "../arch/lapic.h"
 #include "../arch/apic.h"
 
-uint8_t PageFrameAllocator::bitmap[4294967296 / 4096 / 8];
-
-//PageFrame PageFrameList[4294967296 / 4096];
+//uint8_t PageFrameAllocator::bitmap[4294967296 / 4096 / 8];
+PageFrame PageFrameAllocator::PageFrames[4294967296 / 4096];
 
 void mark_pageframes(uintptr_t start, uintptr_t end, bool available){
     DBG << "start: " << hex << start << " end: " << end;
@@ -20,10 +19,12 @@ void mark_pageframes(uintptr_t start, uintptr_t end, bool available){
 
     for(uint64_t i = start; i < end; i += 4096){
         uint64_t pg = i/4096;
-        if(available)
-            PageFrameAllocator::bitmap[pg/8] |= (1 << pg%8);
-        else
-            PageFrameAllocator::bitmap[pg/8] &= ~(1 << pg%8);
+
+        PageFrameAllocator::PageFrames[pg].available = available;
+        //if(available)
+        //    PageFrameAllocator::bitmap[pg/8] |= (1 << pg%8);
+        //else
+        //    PageFrameAllocator::bitmap[pg/8] &= ~(1 << pg%8);
     }
 }
 
@@ -83,8 +84,9 @@ void PageFrameAllocator::stats(){
     }
 
     uint64_t pages_available = 0;
-    for(uint64_t i=0; i<sizeof(bitmap)*8;i++){
-        if(bitmap[i/8] & (1<<i%8))
+    for(uint64_t i=0; i<(sizeof(PageFrames)/sizeof(PageFrames[0]));i++){
+        if(PageFrames[i].available)
+        //if(bitmap[i/8] & (1<<i%8))
             pages_available++;
     }
     for(uint64_t i=0; i < 0x2000000/4096/8; i++){
@@ -92,17 +94,15 @@ void PageFrameAllocator::stats(){
             DBG << endl << hex << i * 8 * 4096 << " " << flush;
             int x,y;
             dout.getPos(x,y);
-            for(uint8_t i=x; i<10; i++){
+            for(uint8_t j=x; j<10; j++){
                 DBG<<" ";
             }
         }
 
-        if(bitmap[i] == 0xff)
+        if(PageFrames[i].available)
             DBG << '#';
-        else if(bitmap[i] == 0x00)
-            DBG << '.';
         else
-            DBG << '/';
+            DBG << '.';
     }
     DBG << "\npages available: " << dec << pages_available << endl;
 }
@@ -122,7 +122,7 @@ PageFrame* PageFrameAllocator::alloc(bool kernel){
     uint64_t free_pageframe=0;
     //TODO make this more efficent
     for(uint64_t i=search_start/4096; i < search_end/4096; i++){
-        if(bitmap[i/8]&(1<<i%8)){
+        if(PageFrames[i].available){
             free_pageframe = i;
             break;
         }
@@ -132,7 +132,7 @@ PageFrame* PageFrameAllocator::alloc(bool kernel){
         return 0;
 
     mark_pageframes(free_pageframe*4096, free_pageframe*4096, false);
-    return 0;
+    return &PageFrames[free_pageframe];
 }
 
 void PageFrameAllocator::free(PageFrame* frame){
diff --git a/kernel/memory/pageframealloc.h b/kernel/memory/pageframealloc.h
index c96120d..b010195 100644
--- a/kernel/memory/pageframealloc.h
+++ b/kernel/memory/pageframealloc.h
@@ -7,6 +7,7 @@
 
 namespace PageFrameAllocator {
     extern uint8_t bitmap[4294967296 / 4096 / 8];
+    extern PageFrame PageFrames[4294967296 / 4096];
 	//Queue<PageFrame> PageFrameList;
 
     void init ();