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-rw-r--r--bootloader/paging.c295
1 files changed, 295 insertions, 0 deletions
diff --git a/bootloader/paging.c b/bootloader/paging.c
new file mode 100644
index 0000000..d3d6dba
--- /dev/null
+++ b/bootloader/paging.c
@@ -0,0 +1,295 @@
+#include <efi.h>
+#include <efilib.h>
+#include <stdint.h>
+
+#include "memorytypes.h"
+#include "paging_struct.h"
+#include "memory.h"
+
+uint64_t size;
+uint64_t baseaddr;
+uint64_t current;
+
+uint64_t count;
+
+EFI_PHYSICAL_ADDRESS pages;
+uint64_t * CR3;
+
+uint64_t virtualmemory;
+uint64_t maxneg;
+//uint64_t base_memory;
+
+uint64_t GetNextEntry()
+{
+ uint64_t ret = current + 0x1000;//1024*4;
+
+ count++;
+
+ if(count > 1023)
+ {
+ // need to allocate new page
+ // 1024 pages for 4MB
+ EFI_STATUS allocstatus = uefi_call_wrapper(BS->AllocatePages, 4, AllocateAnyPages, MEM_PAGING, size, &pages);
+ if(allocstatus != EFI_SUCCESS)
+ {
+ Print(L"Paging space allocation failed\n");
+ Print(L"Current: 0x%llX \n", current);
+ return -1;
+ }
+ bootloader_memset((void*)pages, size*0x1000, 0x0);
+ baseaddr = (uint64_t)pages;
+ ret = baseaddr;
+
+ //Print(L"New Chunk: 0x%llX\n", baseaddr);
+ count = 0;
+
+ current = ret;
+
+ if(ret % 0x1000 != 0)
+ {
+ Print(L"WARNING Memory not aligned\n");
+ }
+
+ return ret;
+ }
+
+ //Print(L"New Entry: 0x%llX\n", ret);
+ current = ret;
+
+ if(ret % 0x1000 != 0)
+ {
+ Print(L"WARNING Memory not aligned\n");
+ }
+
+ return ret;
+}
+
+uint8_t NeedAllocation(uint64_t in)
+{
+ if(in == -1)
+ {
+ return 1;
+ }
+
+ return 0;
+}
+
+UINT64 EFIAPI GetVMCPUID()
+{
+ long out = 0;
+ long id = 0x80000008;
+
+ __asm__ __volatile__ ("movq %1, %%rax;"
+ "cpuid;"
+ "movq %%rax, %0;"
+ :"=r"(out)
+ :"r"(id)
+ );
+
+ return out;
+}
+
+uint64_t powerTwo(uint64_t power)
+{
+ uint64_t ret = 1;
+
+ while(power > 0)
+ {
+ ret *= 2;
+
+ power--;
+ }
+
+ return ret;
+}
+
+void initCR3()
+{
+ UINT64 cpu = GetVMCPUID();
+
+ CPUIDsizes * sizes = (CPUIDsizes*)&cpu;
+
+ // Print(L"raw: %x\n", cpu);
+ // Print(L"Physical: %d\n", sizes->PhysicalAddress);
+ // Print(L"Virtual: %d\n", sizes->VirtualAddress);
+ virtualmemory = sizes->PhysicalAddress;
+
+ maxneg = powerTwo(virtualmemory) - 1;
+
+ size = 1024;
+
+ Print(L"Started CR3\n");
+
+ // 1024 pages for 4MB
+ EFI_STATUS allocstatus = uefi_call_wrapper(BS->AllocatePages, 4, AllocateAnyPages, MEM_PAGING, size, &pages);
+ if(allocstatus != EFI_SUCCESS)
+ {
+ Print(L"Paging space allocation failed\n");
+ return;
+ }
+
+ count = 1;
+
+ // 1024 pages at 4kb each
+ bootloader_memset((void*)pages, size*4*1024, 0x0);
+
+ baseaddr = (uint64_t)pages;
+ current = baseaddr;
+
+ CR3 = (uint64_t*)current;
+ *CR3 = 0;
+
+ *CR3 |= CR3_PCD;
+ *CR3 |= CR3_PWT;
+ //*CR3 |=(maxneg << CR3_ADDR_SHIFT);
+
+ //((s_CR3*)CR3)->PCD = 1;
+ //((s_CR3*)CR3)->PWT = 1;
+ //((s_CR3*)CR3)->base_addr = GetNextEntry();
+
+
+ //int32_t pml4es = sizeof(s_PML4E);
+
+
+ //((s_CR3*)CR3)->base_addr = maxneg;
+
+}
+
+void printCR3()
+{
+ Print(L"CR3 value: 0x%llX\n", *((uint64_t*)CR3));
+}
+
+void writeCR3()
+{
+ __asm__ __volatile__("movq %0, %%cr3;"
+ :
+ :"r"(*CR3));
+}
+
+void SetVirtualAddress(uint64_t phy, uint64_t virt)
+{
+ uint64_t* pml4 = (uint64_t*)MaskPhyAddr(*CR3);
+
+ // Get the offsets to each page table
+ uint64_t pml4offset = GetPML4Offset(virt);
+ uint64_t pdpoffset = GetPDPOffset(virt);
+ uint64_t pdoffset = GetPDOffset(virt);
+ uint64_t ptoffset = GetPTOffset(virt);
+
+
+ uint64_t pml4e = pml4[pml4offset];
+
+ // if not present, allocate the page
+ if((pml4e & PE_P) == 0x0ull)
+ {
+ //assign the physical addr, and clear all to zero
+ uint64_t tmpaddr = GetNextEntry();
+ pml4e |= MaskPhyAddr(tmpaddr);
+
+ // initialize the page
+ pml4e |= PE_P;
+ pml4e |= PE_RW;
+ pml4e |= PE_US;
+ pml4e |= PE_PWT;
+ pml4e |= PE_PCD;
+ }
+ // assign the values to the array
+ pml4[pml4offset] = pml4e;
+
+
+ uint64_t pdpe = ((uint64_t*)MaskPhyAddr(pml4e))[pdpoffset];
+ if((pdpe & PE_P) == 0x0ull)
+ {
+ // page not present
+ uint64_t tmpaddr = GetNextEntry();
+ pdpe |= MaskPhyAddr(tmpaddr);
+
+ pdpe |= PE_P;
+ pdpe |= PE_RW;
+ pdpe |= PE_US;
+ pdpe |= PE_PWT;
+ pdpe |= PE_PCD;
+ }
+ ((uint64_t*)MaskPhyAddr(pml4e))[pdpoffset] = pdpe;
+
+ uint64_t pde = ((uint64_t*)MaskPhyAddr(pdpe))[pdoffset];
+
+ if((pde & PE_P) == 0x0ull)
+ {
+ uint64_t tmpaddr = GetNextEntry();
+
+ pde |= MaskPhyAddr(tmpaddr);
+
+ pde |= PE_P;
+ pde |= PE_RW;
+ pde |= PE_US;
+ pde |= PE_PWT;
+ pde |= PE_PCD;
+ }
+ ((uint64_t*)MaskPhyAddr(pdpe))[pdoffset] = pde;
+
+ uint64_t pte = ((uint64_t*)MaskPhyAddr(pde))[ptoffset];
+
+ // need to make the pt entry
+
+ if((pte & PE_P) == 0x0ull)
+ {
+ pte |= PE_P;
+ pte |= PE_RW;
+ pte |= PE_US;
+ pte |= PE_PWT;
+ pte |= PE_PCD;
+ pte |= MaskPhyAddr(phy);
+ }
+ ((uint64_t*)MaskPhyAddr(pde))[ptoffset] = pte;
+}
+
+uint8_t checkIdentity(uint64_t phy)
+{
+ //uint8_t phyvalue = (uint8_t)(*(uint64_t*)phy);
+ uint8_t phyvalue = *(uint64_t*)phy;
+ uint8_t virtvalue;
+ uint64_t pml4e = CR3GetAddr(*CR3);// + GetPML4Offset(phy);
+ pml4e = *(((uint64_t*)pml4e) + GetPML4Offset(phy));
+ uint64_t pdpe = *(((uint64_t*)GetAddr(pml4e)) + GetPDPOffset(phy));
+ uint64_t pde = *(((uint64_t*)GetAddr(pdpe)) + GetPDOffset(phy));
+ uint64_t pte = *(((uint64_t*)GetAddr(pde)) + GetPTOffset(phy));
+ uint64_t pteptr = ((GetAddr(pte)) + GetPhyOffset(phy));
+ virtvalue = *(uint64_t*)((GetAddr(pte)) + GetPhyOffset(phy));
+
+ //s_PDPE * pdpe = ((s_PDPE*)(pml4e->PDPBA + 8*virt->PDP));
+ //s_PDE * pde = ((s_PDE*)(pdpe->PDBA + 8*virt->PD));
+ //s_PTE * pte = ((s_PTE*)(pde->PTBA + 8*virt->PT));
+ //virtvalue = *(uint8_t*)(pte->PPBA + virt->offset);
+
+ // get the correct virtual value
+
+ Print(L"ADDR: 0x%llx\n", phy);
+
+ Print(L"PML4E 0x%llx\n", pml4e);
+ Print(L"PDPE 0x%llx\n", pdpe);
+ Print(L"PDE 0x%llx\n", pde);
+ Print(L"PTE 0x%llx\n", pte);
+ Print(L"pageentry: 0x%llx\n", pteptr);
+ Print(L"PPBA 0x%llx\n", GetAddr(pte));
+
+ Print(L"PML4 %d\n", GetPML4Offset(phy));
+ Print(L"PDP %d\n", GetPDPOffset(phy));
+ Print(L"PD %d\n", GetPDOffset(phy));
+ Print(L"PT %d\n", GetPTOffset(phy));
+ Print(L"PHY 0x%llx\n", GetPhyOffset(phy));
+
+
+ Print(L"PHYSICAL: 0x%x\n", phyvalue);
+ Print(L"VIRTUAL: 0x%x\n", virtvalue);
+
+ if(phyvalue != virtvalue)
+ {
+ Print(L"Incorrect physical virtual value\n");
+ return 0;
+ }
+
+ Print(L"Correct physical virtual value\n");
+ return 1;
+}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2026-08-18 17:37:19 +0000