Added a malloc function. 90% guaranteed to work!

kernel/hal/dummy/c_include/macro.h

@@ -0,0 +1,2 @@
+#define MIN(a,b) ((a)>(b))?(b):(a)
+#define MAX(a,b) ((a)<(b))?(b):(a)

kernel/hal/dummy/include/pmm.hpp

@@ -8,9 +8,9 @@ private:
 public:
 	auto markUsed(void * addr) -> void;
 	auto init(struct multiboot_info*) -> void;
-	auto operator >> (void * &addr) -> QDPMM &; //alloc
-	auto operator << (const void * addr) -> QDPMM &; //free
-
+	auto operator >> (void * &addr) -> PMM &; //alloc
+	auto operator << (const void * addr) -> PMM &; //free
+	auto operator () (uint32_t len) -> void*;
 };
 }
 #endif

kernel/hal/x86/c_include/macro.h

@@ -0,0 +1,2 @@
+#define MIN(a,b) ((a)>(b))?(b):(a)
+#define MAX(a,b) ((a)<(b))?(b):(a)

kernel/hal/x86/include/pmm.hpp

@@ -1,20 +1,23 @@
 #ifndef _PMM_HPP
 #define _PMM_HPP
-#include <qdpmm.hpp>
+#include <pmm2.hpp>
 #include <stdint.h>
 #include <multiboot.h>
 namespace MTGosHAL {
+struct malloc_t {
+  uint32_t len;
+  malloc_t *last;
+  malloc_t *next;
+};
 class PMM {
 private:
-	uint16_t **pageTable;
-  QDPMM qdpmm;
+  malloc_t *head;
+  PMM2 pmm2;
 public:
   PMM();
-  auto markUsed(const void * addr, uint32_t length) -> bool;
   auto init(struct multiboot_info*) -> void;
-  auto operator >> (void * &addr) -> PMM &; //alloc
-  auto operator << (const void * addr) -> PMM &; //free
-  auto operator()(int pages) -> void*; //alloc_multipage
+  auto alloc(uint32_t length) -> void *;
+  auto free(void* ptr) -> bool;
 };
 }
 #endif

kernel/hal/x86/include/pmm2.hpp

@@ -0,0 +1,20 @@
+#ifndef _PMM2_HPP
+#define _PMM2_HPP
+#include <pmm3.hpp>
+#include <stdint.h>
+#include <multiboot.h>
+namespace MTGosHAL {
+class PMM2 {
+private:
+	uint16_t **pageTable;
+  PMM3 pmm3;
+public:
+	PMM2();
+  auto markUsed(const void * addr, uint32_t length) -> bool;
+  auto init(struct multiboot_info*) -> void;
+  auto operator >> (void * &addr) -> PMM2 &; //alloc
+  auto operator << (const void * addr) -> PMM2 &; //free
+  auto operator()(int pages) -> void*; //alloc_multipage
+};
+}
+#endif

kernel/hal/x86/include/pmm3.hpp

@@ -1,18 +1,18 @@
-#ifndef _QDPMM_HPP
-#define _QDPMM_HPP
+#ifndef _PMM3_HPP
+#define _PMM3_HPP
 #include <stdint.h>
 #include <multiboot.h>
 namespace MTGosHAL {
-class QDPMM {
+class PMM3 {
 private:
 	uint32_t bitmap[0x8000]; //Enough for 4 GB
 protected:
 public:
-	QDPMM();
+	PMM3();
 	auto markUsed(const void * addr) -> void;
 	auto init(struct multiboot_info*) -> void;
-	auto operator >> (void * &addr) -> QDPMM &; //alloc
-	auto operator << (const void * addr) -> QDPMM &; //free
+	auto operator >> (void * &addr) -> PMM3 &; //alloc
+	auto operator << (const void * addr) -> PMM3 &; //free
 };
 }
 #endif

kernel/hal/x86/init/Multitasking.cpp

@@ -27,9 +27,7 @@ Multitasking::Multitasking(): curr_task(nullptr), first_task(nullptr)
 }
 auto Multitasking::initTask(void(* entry)()) -> struct cpu_state*
 {
-    void *tmp1, *tmp2;
-    mm >> tmp1 >> tmp2;
-    uint8_t *stack=(uint8_t*)tmp1, *user_stack=(uint8_t*)tmp2;
+    uint8_t *stack=(uint8_t*)mm.alloc(4096), *user_stack=(uint8_t*)mm.alloc(4096);
     struct cpu_state new_state = {
         0, //EAX
         0, //EBX

kernel/hal/x86/init/init.cpp

@@ -44,11 +44,29 @@ namespace MTGosHAL {
 		idt.setEntry(8, (void *)((uint32_t)&intr_stub_0+128), SEG_DBL_FAULT, IDT_TASK_GATE | IDT_SEG_32_BIT | IDT_RING_0 | IDT_USED);
 		idt.apply();
 		mm.init(ebx);
+    debug << "Now tesing the PMM... Allocating 1 byte\n";
+    char* tmp=(char*)mm.alloc(1);
+    debug << "Allocating another byte\n";
+    char* tmp2=(char*)mm.alloc(1);
+    tmp2[0]='A';
+    debug << "Freeing the first byte...\n";
+    mm.free((void*)tmp);
+    debug << "Allocating 14 bytes... \n";
+    tmp=(char*)mm.alloc(14);
+    debug << "Changing the last byte... \n";
+    tmp[13]='B';
+    debug << "Changing if the second byte has changed...\n";
+    if(tmp2[0]=='B') {
+      err << "The allocate function is broken.\n";
+      debug << "The allocate function is broken.\n";
+    } else {
+      debug << "The allocate function works!\n";
+    }
+    debug << "Freeing up both pointers.";
+    mm.free((void*)tmp);
+    mm.free((void*)tmp2);
     multiboot_mod_list *mods = (multiboot_mod_list*) ebx->mods_addr;
-		void** progs=nullptr;
-		void* tmp;
-		mm >> tmp;
-		progs=(void**)tmp;
+		void** progs=(void**)mm.alloc(4096);
 		uint32_t i;
 		for(i=0;i<(ebx->mods_count<1023?ebx->mods_count:1023);i++) { //Basically until MIN(ebx->mods_count, 1023), as we only support loading up to 1023 programs directly.
 			progs[i]=(void*)(mods[i].mod_start);

kernel/hal/x86/mm/pmm.cpp

@@ -1,125 +1,107 @@
-#include <pmm.hpp>
 #include <base.hpp>
-//In this part, please remember that the address is split into 3 parts. Bitmap:
-// AAAA AAAA ABBB BBBB BBBB CCCC CCCC CCCC
-#define SPLIT1_FLAG 0xFF800000ul
-#define SPLIT1_SHIFT(a) ((a)<<23)
-#define SPLIT1_UNSHIFT(a) ((a)>>23)
-#define SPLIT2_FLAG 0x007FF000ul
-#define SPLIT2_SHIFT(a) ((a)<<12)
-#define SPLIT2_UNSHIFT(a) (((a)<<23)&0x7FF)
-#define SPLIT3_FLAG 0x00000FFFul
-#define SPLIT3_SHIFT(a) ((a))
-#define SPLIT3_UNSHIFT(a) ((a)&0xFFF)
+#include <pmm.hpp>
 extern "C" const int kernel_start;
 extern "C" const int kernel_end; //those are voids actually
 void *operator new(size_t size) {
-	if(size>4096) {
-    return MTGosHAL::mm(size/4096);
-	}
-	void *ptr;
-	MTGosHAL::mm >> ptr;
-	return ptr;
+  return MTGosHAL::mm.alloc(size);
 }
 void *operator new[](size_t size)  {
-  if(size>4096) {
-    return MTGosHAL::mm(size/4096);
-	}
-	void *ptr;
-	MTGosHAL::mm >> ptr;
-	return ptr;
+  return MTGosHAL::mm.alloc(size);
 }
 void operator delete(void* p) {
-	MTGosHAL::mm << p;
+	MTGosHAL::mm.free(p);
 }
 void operator delete[](void* p) {
-	MTGosHAL::mm << p;
+	MTGosHAL::mm.free(p);
 }
 void operator delete(void* p, size_t size) {
-	MTGosHAL::mm << p;
+	MTGosHAL::mm.free(p);
 }
 void operator delete[](void* p, size_t size) {
-	MTGosHAL::mm << p;
+	MTGosHAL::mm.free(p);
 }
 namespace MTGosHAL {
-PMM::PMM(): qdpmm() {
-}
-
-auto PMM::markUsed(const void * addr, uint32_t length) -> bool {
-  uint32_t add=(uint32_t)addr;
-  uint32_t pagetid = SPLIT1_UNSHIFT(add);
-  if(length > 256*1024*1024) //Maximum allocation limit is 256MB
-    return false;
-  if(!pageTable[pagetid]) {
-    void* temp;
-    qdpmm >> temp;
-    pageTable[pagetid]=(uint16_t*)temp;
-    for(int i=0;i<2048;i++)
-      pageTable[pagetid][i]=0;
-    markUsed(pageTable[pagetid],1024); //Not a mistake
-  }
-  //Check if used
-  for(uint32_t curr_addr=add+length;curr_addr>=add;curr_addr-=0x1000) {
-    if(pageTable[SPLIT1_UNSHIFT(curr_addr)][SPLIT2_UNSHIFT(curr_addr)])
-      return false;
-  }
-  //Mark as used
-  uint16_t counter=1;
-  for(uint32_t curr_addr=add+length;curr_addr>=add;curr_addr-=0x1000) {
-    pageTable[SPLIT1_UNSHIFT(curr_addr)][SPLIT2_UNSHIFT(curr_addr)]=counter++;
-    qdpmm.markUsed((void*)curr_addr);
-  }
-  return true;
-}
-
-auto PMM::operator >> (void * &addr) -> PMM & {
-  qdpmm >> addr;
-  markUsed(addr,4096);
-  return *this;
-}
-auto PMM::operator << (const void *addr) -> PMM & {
-  uint32_t add=(uint32_t)addr;
-  if(!pageTable[SPLIT1_UNSHIFT(add)])
-    return *this; //Prevent nullptr derefs
-  for(int i=0;i<pageTable[SPLIT1_UNSHIFT(add)][SPLIT2_UNSHIFT(add)];i++) {
-    pageTable[SPLIT1_UNSHIFT(add+i*4096)][SPLIT2_UNSHIFT(add+i*4096)]=0;
-    qdpmm << (void*)(add+i*4096);
-  }
-  return *this;
-}
-auto PMM::operator()(int pages) -> void* {
-  //I want to get this working so:
-  //TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO
-  // NEVER USE A BRUTE-FORCE ALGO TO ALLOC PAGES!
-  //TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO
-  for(uint32_t i=0;i<(uint32_t)(-(pages*4096));i+=4096) {
-    if(markUsed((void*)i,pages*4096))
-      return (void*)i;
-  }
-  return nullptr;
-}
+PMM::PMM(): head(nullptr), pmm2() {}
 auto PMM::init(struct multiboot_info* mb_info) -> void {
-  qdpmm.init(mb_info);
-  void *temp;
-  qdpmm >> temp;
-  pageTable=(uint16_t**)temp;
-  for(int i=0;i<4096;i++)
-    pageTable[i]=nullptr;
-  markUsed(pageTable,4096);
-  markUsed((void*)nullptr,4096);
-  struct multiboot_mmap_entry* mmap = (struct multiboot_mmap_entry*) mb_info->mmap_addr;
-	struct multiboot_mmap_entry* mmap_end = (struct multiboot_mmap_entry*) ((unsigned int) mb_info->mmap_addr + mb_info->mmap_length);
-  while(mmap < mmap_end) {
-    if(mmap->type != 1) {
-      markUsed((void*)mmap->addr,mmap->len);
+  pmm2.init(mb_info);
+}
+auto PMM::alloc(uint32_t length) -> void * {
+  if(!head) {
+    //Alloc space for head
+    if(length+sizeof(malloc_t)<=4096) { //Small optimization. The routine for allocating more than one continuous page is terribly slow.
+      void *tmp;
+      pmm2 >> tmp;
+      head=(malloc_t*)tmp;
+    } else
+      head=(malloc_t*)pmm2(((length+sizeof(malloc_t))>>12)+1);
+    if(!head) //The alloc() didn't work! We're out of RAM!
+      return nullptr;
+    head->len=length;
+    head->next=head->last=nullptr;
+    malloc_t* tmp=head;
+    tmp++;
+    return (void*)tmp;
   }
-    mmap++;
+  malloc_t* curr=head;
+  malloc_t* last=nullptr;
+  do {
+    uint32_t loc=(uint32_t)curr+sizeof(malloc_t)+curr->len;
+    if((loc+length+sizeof(malloc_t))<((loc&(~0xFFF))+4096)) {
+      malloc_t *allocd=(malloc_t *)loc;
+      allocd->len=length;
+      allocd->last=curr;
+      allocd->next=curr->next; //Set double linked list
+      curr->next=allocd;
+      if(allocd->next)
+        allocd->next->last=allocd;
+      malloc_t *tmp=allocd;
+      tmp++;
+      return (void*)tmp;
     }
-  markUsed(&kernel_start,((uint32_t)&kernel_end)-((uint32_t)&kernel_start)); //Protect kernel)
-  multiboot_mod_list *mods = (multiboot_mod_list*) mb_info->mods_addr;
-	for(uint32_t i=0;i<mb_info->mods_count;i++) {
-		markUsed((void*)((uint32_t)(&mods[i])&(~0xFFF)),4096); //Mark all of the module table as used
-    markUsed((void*)mods[i].mod_start,mods[i].mod_end-mods[i].mod_start);
+    last=curr;
+    curr=curr->next;
+  } while(curr);
+  malloc_t *allocd=nullptr;
+  if(length+sizeof(malloc_t)<=4096) { //Small optimization. The routine for allocating more than one continuous page is terribly slow.
+    void *tmp;
+    pmm2 >> tmp;
+    allocd=(malloc_t*)tmp;
+  } else
+    allocd=(malloc_t*)pmm2(((length+sizeof(malloc_t))>>12)+1);
+  if(!allocd) //The alloc() didn't work! We're out of RAM!
+    return nullptr;
+  last->next=allocd;
+  allocd->len=length;
+  allocd->last=last;
+  allocd->next=nullptr;
+  malloc_t *tmp=allocd;
+  tmp++;
+  return (void*)tmp;
+}
+auto PMM::free(void* ptr) -> bool {
+  if(!ptr)
+    return false;
+  malloc_t* curr=head;
+  malloc_t* chk=(malloc_t*)ptr;
+  chk--;
+  do {
+    if(curr==chk) {
+      uint32_t start=((uint32_t)chk)&(~0xFFF);
+      uint32_t end=start+0x1000;
+      if((((uint32_t)(curr->last)<start)||((uint32_t)(curr->last)>=end))&&(((uint32_t)(curr->next)>=end)||((uint32_t)(curr->next)<start))) {
+        pmm2 << (void*)start;
       }
+      if(curr->last)
+        curr->last->next=curr->next;
+      else {
+        head=curr->next;
+      }
+      if(curr->next)
+        curr->next->last=curr->last;
+      return true;
+    }
+    curr=curr->next;
+  } while(curr);
+  return false;
 }
 }

kernel/hal/x86/mm/pmm2.cpp

@@ -0,0 +1,98 @@
+#include <pmm2.hpp>
+#include <base.hpp>
+//In this part, please remember that the address is split into 3 parts. Bitmap:
+// AAAA AAAA ABBB BBBB BBBB CCCC CCCC CCCC
+#define SPLIT1_FLAG 0xFF800000ul
+#define SPLIT1_SHIFT(a) ((a)<<23)
+#define SPLIT1_UNSHIFT(a) ((a)>>23)
+#define SPLIT2_FLAG 0x007FF000ul
+#define SPLIT2_SHIFT(a) ((a)<<12)
+#define SPLIT2_UNSHIFT(a) (((a)<<23)&0x7FF)
+#define SPLIT3_FLAG 0x00000FFFul
+#define SPLIT3_SHIFT(a) ((a))
+#define SPLIT3_UNSHIFT(a) ((a)&0xFFF)
+extern "C" const int kernel_start;
+extern "C" const int kernel_end; //those are voids actually
+
+namespace MTGosHAL {
+PMM2::PMM2(): pmm3() {
+}
+
+auto PMM2::markUsed(const void * addr, uint32_t length) -> bool {
+  uint32_t add=(uint32_t)addr;
+  uint32_t pagetid = SPLIT1_UNSHIFT(add);
+  if(length > 256*1024*1024) //Maximum allocation limit is 256MB
+    return false;
+  if(!pageTable[pagetid]) {
+    void* temp;
+    pmm3 >> temp;
+    pageTable[pagetid]=(uint16_t*)temp;
+    for(int i=0;i<2048;i++)
+      pageTable[pagetid][i]=0;
+    markUsed(pageTable[pagetid],1024); //Not a mistake
+  }
+  //Check if used
+  for(uint32_t curr_addr=add+length;curr_addr>=add;curr_addr-=0x1000) {
+    if(pageTable[SPLIT1_UNSHIFT(curr_addr)][SPLIT2_UNSHIFT(curr_addr)])
+      return false;
+  }
+  //Mark as used
+  uint16_t counter=1;
+  for(uint32_t curr_addr=add+length;curr_addr>=add;curr_addr-=0x1000) {
+    pageTable[SPLIT1_UNSHIFT(curr_addr)][SPLIT2_UNSHIFT(curr_addr)]=counter++;
+    pmm3.markUsed((void*)curr_addr);
+  }
+  return true;
+}
+
+auto PMM2::operator >> (void * &addr) -> PMM2 & {
+  pmm3 >> addr;
+  markUsed(addr,4096);
+  return *this;
+}
+auto PMM2::operator << (const void *addr) -> PMM2 & {
+  uint32_t add=(uint32_t)addr;
+  if(!pageTable[SPLIT1_UNSHIFT(add)])
+    return *this; //Prevent nullptr derefs
+  for(int i=0;i<pageTable[SPLIT1_UNSHIFT(add)][SPLIT2_UNSHIFT(add)];i++) {
+    pageTable[SPLIT1_UNSHIFT(add+i*4096)][SPLIT2_UNSHIFT(add+i*4096)]=0;
+    pmm3 << (void*)(add+i*4096);
+  }
+  return *this;
+}
+auto PMM2::operator()(int pages) -> void* {
+  //I want to get this working so:
+  //TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO
+  // NEVER USE A BRUTE-FORCE ALGO TO ALLOC PAGES!
+  //TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO TODO
+  for(uint32_t i=0;i<(uint32_t)(-(pages*4096));i+=4096) {
+    if(markUsed((void*)i,pages*4096))
+      return (void*)i;
+  }
+  return nullptr;
+}
+auto PMM2::init(struct multiboot_info* mb_info) -> void {
+  pmm3.init(mb_info);
+  void *temp;
+  pmm3 >> temp;
+  pageTable=(uint16_t**)temp;
+  for(int i=0;i<4096;i++)
+    pageTable[i]=nullptr;
+  markUsed(pageTable,4096);
+  markUsed((void*)nullptr,4096);
+  struct multiboot_mmap_entry* mmap = (struct multiboot_mmap_entry*) mb_info->mmap_addr;
+	struct multiboot_mmap_entry* mmap_end = (struct multiboot_mmap_entry*) ((unsigned int) mb_info->mmap_addr + mb_info->mmap_length);
+  while(mmap < mmap_end) {
+    if(mmap->type != 1) {
+      markUsed((void*)mmap->addr,mmap->len);
+    }
+    mmap++;
+  }
+  markUsed(&kernel_start,((uint32_t)&kernel_end)-((uint32_t)&kernel_start)); //Protect kernel)
+  multiboot_mod_list *mods = (multiboot_mod_list*) mb_info->mods_addr;
+	for(uint32_t i=0;i<mb_info->mods_count;i++) {
+		markUsed((void*)((uint32_t)(&mods[i])&(~0xFFF)),4096); //Mark all of the module table as used
+    markUsed((void*)mods[i].mod_start,mods[i].mod_end-mods[i].mod_start);
+	}
+}
+}

kernel/hal/x86/mm/pmm3.cpp

@@ -1,12 +1,12 @@
 #include <stdint.h>
 #include <base.hpp>
-#include <qdpmm.hpp>
+#include <pmm3.hpp>
 #include <multiboot.h>
 extern "C" const int kernel_start;
 extern "C" const int kernel_end; //those are voids actually
 namespace MTGosHAL {
-QDPMM::QDPMM() {}
-auto QDPMM::init(struct multiboot_info * mb_info) -> void {
+PMM3::PMM3() {}
+auto PMM3::init(struct multiboot_info * mb_info) -> void {
 	for(int i=0;i<0x8000;i++)
 		bitmap[i]=0;
 	struct multiboot_mmap_entry* mmap = (struct multiboot_mmap_entry*) mb_info->mmap_addr;
@@ -37,14 +37,14 @@ auto QDPMM::init(struct multiboot_info * mb_info) -> void {
 		}
 	}
 }
-auto QDPMM::markUsed(const void * addr) -> void {
+auto PMM3::markUsed(const void * addr) -> void {
 	unsigned int address=(unsigned int)addr;
 	address>>=12;
 	int index=address>>5;
 	int bit=1<<(address&0x1F);
 	bitmap[index]&=~bit;
 }
-auto QDPMM::operator >> (void * &addr) -> QDPMM & {
+auto PMM3::operator >> (void * &addr) -> PMM3 & {
 	for(int i=0;i<0x8000;i++) {
 		if(!bitmap[i])
 			continue;
@@ -60,7 +60,7 @@ auto QDPMM::operator >> (void * &addr) -> QDPMM & {
 	addr=nullptr;
 	return *this;
 }
-auto QDPMM::operator << (const void * addr) -> QDPMM & {
+auto PMM3::operator << (const void * addr) -> PMM3 & {
 	unsigned int address=(unsigned int)addr;
 	address>>=12;
 	int index=address>>5;

user/test.c

@@ -1,6 +1,6 @@
 
+static unsigned short* videomem = (unsigned short*) 0xb8000;
 void temp() {
-  static unsigned short* videomem = (unsigned short*) 0xb8000;
      int i;
     for (i = 0; i < 3; i++) {
         *videomem++ = (0x07 << 8) | ('0' + i);