| 14,6 → 14,9 |
|---|
| |
| align 4 |
| proc mem_test |
| ; if we have BIOS with fn E820, skip the test |
| cmp dword [BOOT_VAR-OS_BASE + 0x9100], 0 |
| jnz .ret |
| |
| mov eax, cr0 |
| and eax, not (CR0_CD+CR0_NW) |
| 29,27 → 32,80 |
|---|
| cmp dword [edi], 'TEST' |
| xchg ebx, dword [edi] |
| je @b |
| mov [MEM_AMOUNT-OS_BASE], edi |
| |
| and eax, not (CR0_CD+CR0_NW) ;enable caching |
| mov cr0, eax |
| mov eax, edi |
| inc dword [BOOT_VAR-OS_BASE + 0x9100] |
| xor eax, eax |
| mov [BOOT_VAR-OS_BASE + 0x9104], eax |
| mov [BOOT_VAR-OS_BASE + 0x9108], eax |
| mov [BOOT_VAR-OS_BASE + 0x910C], edi |
| mov [BOOT_VAR-OS_BASE + 0x9110], eax |
| .ret: |
| ret |
| endp |
| |
| align 4 |
| proc init_mem |
| mov eax, [MEM_AMOUNT-OS_BASE] |
| mov [pg_data.mem_amount-OS_BASE], eax |
| ; calculate maximum allocatable address and number of allocatable pages |
| mov edi, BOOT_VAR-OS_BASE + 0x9104 |
| mov ecx, [edi-4] |
| xor esi, esi ; esi will hold total amount of memory |
| xor edx, edx ; edx will hold maximum allocatable address |
| .calcmax: |
| ; round all to pages |
| mov eax, [edi] |
| test eax, 0xFFF |
| jz @f |
| neg eax |
| and eax, 0xFFF |
| add [edi], eax |
| adc dword [edi+4], 0 |
| sub [edi+8], eax |
| sbb dword [edi+12], 0 |
| jc .unusable |
| @@: |
| and dword [edi+8], not 0xFFF |
| jz .unusable |
| ; ignore memory after 4 Gb |
| cmp dword [edi+4], 0 |
| jnz .unusable |
| mov eax, [edi] |
| cmp dword [edi+12], 0 |
| jnz .overflow |
| add eax, [edi+8] |
| jnc @f |
| .overflow: |
| mov eax, 0xFFFFF000 |
| @@: |
| cmp edx, eax |
| jae @f |
| mov edx, eax |
| @@: |
| sub eax, [edi] |
| mov [edi+8], eax |
| add esi, eax |
| jmp .usable |
| .unusable: |
| and dword [edi+8], 0 |
| .usable: |
| add edi, 20 |
| loop .calcmax |
| .calculated: |
| mov [MEM_AMOUNT-OS_BASE], esi |
| mov [pg_data.mem_amount-OS_BASE], esi |
| shr esi, 12 |
| mov [pg_data.pages_count-OS_BASE], esi |
| |
| shr eax, 12 |
| mov [pg_data.pages_count-OS_BASE], eax |
| shr eax, 3 |
| mov [pg_data.pagemap_size-OS_BASE], eax |
| shr edx, 12 |
| add edx, 31 |
| and edx, not 31 |
| shr edx, 3 |
| mov [pg_data.pagemap_size-OS_BASE], edx |
| |
| add eax, (sys_pgmap-OS_BASE)+4095 |
| and eax, not 4095 |
| mov [tmp_page_tabs], eax |
| add edx, (sys_pgmap-OS_BASE)+4095 |
| and edx, not 4095 |
| mov [tmp_page_tabs], edx |
| |
| mov edx, (((sys_pgmap-OS_BASE) + 0xFFFFFF) and not 0xFFFFFF) shr 12 |
| mov [pg_data.kernel_pages-OS_BASE], edx |
| 121,14 → 177,63 |
|---|
| |
| align 4 |
| proc init_page_map |
| |
| ; mark all memory as unavailable |
| mov edi, sys_pgmap-OS_BASE |
| mov ecx, [pg_data.pagemap_size-OS_BASE] |
| shr ecx, 2 |
| or eax, -1 |
| xor eax, eax |
| cld |
| rep stosd |
| |
| ; scan through memory map and mark free areas as available |
| mov ebx, BOOT_VAR-OS_BASE + 0x9104 |
| mov edx, [ebx-4] |
| .scanmap: |
| mov ecx, [ebx+8] |
| shr ecx, 12 ; ecx = number of pages |
| jz .next |
| mov edi, [ebx] |
| shr edi, 12 ; edi = first page |
| mov eax, edi |
| neg eax |
| shr edi, 5 |
| add edi, sys_pgmap-OS_BASE |
| and eax, 31 |
| jz .startok |
| sub ecx, eax |
| jbe .onedword |
| push ecx |
| mov ecx, eax |
| xor eax, eax |
| inc eax |
| shl eax, cl |
| dec eax |
| or [edi], eax |
| add edi, 4 |
| pop ecx |
| .startok: |
| push ecx |
| shr ecx, 5 |
| or eax, -1 |
| rep stosd |
| pop ecx |
| and ecx, 31 |
| not eax |
| shl eax, cl |
| or [edi], eax |
| jmp .next |
| .onedword: |
| add ecx, eax |
| @@: |
| dec eax |
| bts [edi], eax |
| loop @b |
| .next: |
| add ebx, 20 |
| dec edx |
| jnz .scanmap |
| |
| ; mark kernel memory as allocated (unavailable) |
| mov ecx, [tmp_page_tabs] |
| mov edx, [pg_data.pages_count-OS_BASE] |
| shr ecx, 12 |
| 146,7 → 251,7 |
|---|
| mov ecx, ebx |
| and ecx, 31 |
| shl eax, cl |
| mov [edi], eax |
| and [edi], eax |
| add edi, OS_BASE |
| mov [page_start-OS_BASE], edi; |
| |