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Added a alloc and free function (operators >> and <<) to the PMM.

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Now compiles
This commit is contained in:
Morten Delenk 2016-02-06 20:03:23 +01:00
parent e1203d8271
commit 332f74c9a9
2 changed files with 28 additions and 1 deletions
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2
kernel/hal/x86/include/pmm.hpp
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@ -2,6 +2,7 @@
#define _PMM_HPP
#include <stdint.h>
#include <multiboot.h>
namespace MTGosHAL {
class PMM {
private:
uint32_t bitmap[0x8000]; //Enough for 4 GB
@ -14,4 +15,5 @@ public:
auto operator()(int pages) -> void*; //alloc_multipage
};
}
#endif

27
kernel/hal/x86/mm/pmm.cpp
View file

@ -2,6 +2,7 @@
#include <multiboot.h>
extern "C" const int kernel_start;
extern "C" const int kernel_end; //those are voids actually
namespace MTGosHAL {
PMM::PMM(struct multiboot_info * mb_info) {
for(int i=0;i<0x8000;i++)
bitmap[i]=0;
@ -32,4 +33,28 @@ auto PMM::markUsed(void * addr) -> void {
int bit=1<<(address&0x1F);
bitmap[index]&=~bit;
}
//auto PMM::operator >> (void * &addr) -> PMM &;
auto PMM::operator >> (void * &addr) -> PMM & {
for(int i=0;i<0x8000;i++) {
if(!bitmap[i])
continue;
for(int j=0;j<32;j++) {
if(bitmap[i]&(1<<j)) {
//We found a free page!
bitmap[i]&=(1<<j);
addr=(void*)(((i<<5)+j)<<12);
return *this;
}
}
}
addr=nullptr;
return *this;
}
auto operator << (const void * addr) -> PMM & {
unsigned int address=(unsigned int)addr;
address>>=12;
int index=address>>5;
int bit=1<<(address&0x1F);
bitmap[index]|=bit;
return *this;
}
}