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|
#include <stdlib.h>
#include "kernel.h"
#include "vmem.h"
#include "asm_x86.h"
#include "mem.h"
#include "kmalloc.h"
#include "lib/string/string.h"
//! i86 architecture defines 1024 entries per table--do not change
#define PAGES_PER_TABLE 1024
#define PAGES_PER_DIR 1024
#define PAGE_DIRECTORY_INDEX(x) (((x) >> 22) & 0x3ff)
#define PAGE_TABLE_INDEX(x) (((x) >> 12) & 0x3ff)
#define PAGE_GET_PHYSICAL_ADDRESS(x) (*x & ~0xfff)
//! page table represents 4mb address space
#define PTABLE_ADDR_SPACE_SIZE 0x400000
//! directory table represents 4gb address space
#define DTABLE_ADDR_SPACE_SIZE 0x100000000
//! page sizes are 4kb
#define PAGE_SIZE 4096
//! page table entry
typedef uint32_t pt_entry;
//! a page directery entry
typedef uint32_t pd_entry;
//! page table
typedef struct ptable_struct {
pt_entry m_entries[PAGES_PER_TABLE];
}ptable ;
//! page directory
typedef struct pdirectory_struct {
pd_entry m_entries[PAGES_PER_DIR];
}pdirectory;
static uint32_t kernel_pages;
uint32_t fb_addr; // TODO!??!!? how can we share so ugly with vesa
static uint32_t apic_addr;
static uint32_t io_apic_addr;
// TODO : why is the frame not 0xfffff??
enum PAGE_PTE_FLAGS
{
I86_PTE_PRESENT = 1, //0000000000000000000000000000001
I86_PTE_WRITABLE = 2, //0000000000000000000000000000010
I86_PTE_USER = 4, //0000000000000000000000000000100
I86_PTE_WRITETHOUGH = 8, //0000000000000000000000000001000
I86_PTE_NOT_CACHEABLE = 0x10, //0000000000000000000000000010000
I86_PTE_ACCESSED = 0x20, //0000000000000000000000000100000
I86_PTE_DIRTY = 0x40, //0000000000000000000000001000000
I86_PTE_PAT = 0x80, //0000000000000000000000010000000
I86_PTE_CPU_GLOBAL = 0x100, //0000000000000000000000100000000
I86_PTE_LV4_GLOBAL = 0x200, //0000000000000000000001000000000
I86_PTE_FRAME = 0xFFFFF000 //1111111111111111111000000000000
};
enum PAGE_PDE_FLAGS
{
I86_PDE_PRESENT = 1, //0000000000000000000000000000001
I86_PDE_WRITABLE = 2, //0000000000000000000000000000010
I86_PDE_USER = 4, //0000000000000000000000000000100
I86_PDE_PWT = 8, //0000000000000000000000000001000
I86_PDE_PCD = 0x10, //0000000000000000000000000010000
I86_PDE_ACCESSED = 0x20, //0000000000000000000000000100000
I86_PDE_DIRTY = 0x40, //0000000000000000000000001000000
I86_PDE_4MB = 0x80, //0000000000000000000000010000000
I86_PDE_CPU_GLOBAL = 0x100, //0000000000000000000000100000000
I86_PDE_LV4_GLOBAL = 0x200, //0000000000000000000001000000000
I86_PDE_FRAME = 0xFFFFF000 //1111111111111111111000000000000
};
////
//! virtual address
typedef uint32_t virtual_addr;
typedef uint32_t physical_addr;
////
static void pt_entry_add_attrib (pt_entry* e, uint32_t attrib)
{
*e|=attrib;
}
static void pt_entry_del_attrib (pt_entry* e, uint32_t attrib)
{
*e&=~attrib;
}
static void pt_entry_set_frame (pt_entry* e , physical_addr addr)
{
*e|=I86_PTE_FRAME&addr;
}
static physical_addr pt_entry_get_frame (pt_entry* e)
{
return *e&I86_PTE_FRAME;
}
static bool pt_entry_is_present (pt_entry e)
{
return e&I86_PTE_PRESENT;
}
static bool pt_entry_is_writable (pt_entry e)
{
return e&I86_PTE_WRITABLE;
}
static physical_addr pt_entry_pfn (pt_entry e)
{
return e&I86_PTE_FRAME;
}
static void pd_entry_add_attrib (pd_entry* e, uint32_t attrib)
{
*e|=attrib;
}
static void pd_entry_del_attrib (pd_entry* e, uint32_t attrib)
{
*e&=~attrib;
}
static void pd_entry_set_frame (pd_entry* e, physical_addr add)
{
*e|=I86_PDE_FRAME&add;
}
static physical_addr pd_entry_get_frame (pd_entry* e)
{
return *e&I86_PDE_FRAME;
}
static bool pd_entry_is_present (pd_entry e)
{
return e&I86_PDE_PRESENT;
}
/*
bool pd_entry_is_user (pd_entry e)
{
return 1;
}
bool pd_entry_is_4mb (pd_entry e)
{
return 1;
}
*/
static bool pd_entry_is_writable (pd_entry e)
{
return e&I86_PDE_WRITABLE;
}
static physical_addr pd_entry_pfn (pd_entry e)
{
return e&I86_PDE_FRAME;
}
/*
void pd_entry_enable_global (pd_entry e)
{
}
*/
static uint8_t vmmngr_alloc_page (pt_entry* e)
{
// allocate a free physical frame
void* p = mem_alloc_block ();
if (!p) return 0;
// map it to the page
pt_entry_set_frame (e, (physical_addr)p);
pt_entry_add_attrib (e, I86_PTE_PRESENT);
return 1;
}
static void vmmngr_free_page (pt_entry* e)
{
void* p = (void*)pt_entry_pfn (*e);
if (p) mem_free_block (p);
pt_entry_del_attrib (e, I86_PTE_PRESENT);
}
static pt_entry* vmmngr_ptable_lookup_entry (ptable* p, virtual_addr addr)
{
if (p) return &p->m_entries[ PAGE_TABLE_INDEX (addr) ];
return 0;
}
/// SHIT BELOW THIs LINE
void vmem_free_dir(pdirectory *dir)
{
x86_paging_disable(); //TODO : do not disable this!
uint32_t virt_addr=0;
// first pages are identity mapped (kernel space) just remove links
for(int j=0;j<3;j++)
{
pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt_addr) ];
virt_addr+=1024*4096;
}
// programm space
virt_addr=0x8000000;
for(int j=0;j<2;j++)
{
pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt_addr) ];
ptable *table=pd_entry_get_frame(entry);
for (int i=0, virt=virt_addr; i<1024; i++, virt+=4096)
{
pt_entry pte=&table->m_entries [PAGE_TABLE_INDEX (virt) ];
mem_free_block(pt_entry_get_frame(pte)); // get free space from the memory manager
}
mem_free_block(pd_entry_get_frame (entry));
virt_addr+=1024*4096;
}
// stack
virt_addr=0x8c00000;
for(int j=0;j<1;j++)
{
pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt_addr) ];
ptable *table=pd_entry_get_frame(entry);
for (int i=0, virt=virt_addr; i<1024; i++, virt+=4096)
{
pt_entry pte=&table->m_entries [PAGE_TABLE_INDEX (virt) ];
mem_free_block(pt_entry_get_frame(pte)); // get free space from the memory manager
}
mem_free_block(pd_entry_get_frame (entry));
virt_addr+=1024*4096;
}
mem_free_block(dir);
x86_paging_enable();
}
static pdirectory* vmem_clean_dir()
{
fixme("replace ALLL kballoc with getting the pages from mem/vmem");
pdirectory* dir = (pdirectory*) kballoc(1);
for(int i=0;i<1024;i++)dir->m_entries [i]=0; // zero all
klog("fresh page directory: 0x%X",dir);
return dir;
}
static void vmem_add_alloc(pdirectory* dir,uint32_t start,uint32_t pages)
{
uint32_t virt_addr=start;
for(int j=0;j<2;j++)
{
ptable* table = (ptable*) kballoc (1);
pd_entry *oldentry=NULL;
ptable* oldtable=NULL;
for (int i=0, virt=virt_addr; i<1024; i++, virt+=4096)
{
//klog("i = %d",i);
uint32_t phys_addr=mem_alloc_block(); // get free space from the memory manager
uint32_t frame=phys_addr;
//! create a new page
pt_entry page=0;
pt_entry_add_attrib (&page, I86_PTE_PRESENT);
pt_entry_add_attrib (&page, I86_PTE_WRITABLE);
pt_entry_add_attrib (&page, I86_PTE_USER);
pt_entry_set_frame (&page, frame);
//! ...and add it to the page table
table->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
}
pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt_addr) ];
*entry=0;
pd_entry_add_attrib (entry, I86_PDE_PRESENT);
pd_entry_add_attrib (entry, I86_PDE_WRITABLE);
pt_entry_add_attrib (entry, I86_PTE_USER);
pd_entry_set_frame (entry, (physical_addr)table);
virt_addr+=1024*4096;
}
}
static void vmem_add_identity(pdirectory* dir,uint32_t start,uint32_t pages)
{
fixme("make sure the pages are marked as used in the physical mem manager");
uint32_t phys_addr=start;
uint32_t virt_addr=start;
while(pages>0)
{
// each table in our page directory maps 1024*4096 bytes
ptable* table;
table = (ptable*) kballoc(1);
for(int i=0;i<1024;i++)table->m_entries [i]=0; // zero all
//! idenitity mapping
for (int i=0, frame=phys_addr, virt=virt_addr; i<1024; i++, frame+=4096, virt+=4096)
{
//! create a new page
pt_entry page=0;
pt_entry_add_attrib (&page, I86_PTE_PRESENT);
pt_entry_add_attrib (&page, I86_PTE_WRITABLE);
pt_entry_add_attrib (&page, I86_PTE_USER);
pt_entry_set_frame (&page, frame);
//! ...and add it to the page table
table->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
pages--;
if(pages<=0)break;
}
pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt_addr) ];
*entry=0;
pd_entry_add_attrib (entry, I86_PDE_PRESENT);
pd_entry_add_attrib (entry, I86_PDE_WRITABLE);
pd_entry_add_attrib (entry, I86_PDE_USER);
pd_entry_set_frame (entry, (physical_addr)table);
phys_addr+=1024*4096;
virt_addr+=1024*4096;
}
}
pdirectory* vmem_kernel_dir()
{
fixme("remove user flags where appropriate");
fixme("do not waste soo many pages/page tables!");
fixme("align properly!! / merge page tables if required!");
fixme("Is ioapic/lapic really on one page?");
pdirectory* dir = vmem_clean_dir();
vmem_add_identity(dir,0,1024*8);//first 32 megs
if(fb_addr>0x100000)vmem_add_identity(dir,fb_addr,1024*4);//16megs (?) TODO: dynamic
vmem_add_identity(dir,apic_addr,1024*2);
//vmem_add_identity(dir,io_apic_addr,1024*2); // we do not nee this (ioapic never accessed after paging enabled)
vmem_add_alloc(dir,0x8000000,1024*4);
return dir;
}
//
// vmem init / also copies all the shit over for FORK
// if copy_dir==NULL creates brandnew dir
// otherwise copies kernel pages and copies
// programm pages procreates new programmspace
//
// TODO: FIX
// KERNEL SPACE `kernel_pages` first 8 PAGES = 32megs
// FRAMEBUFER WE GET ON INIT
// PROGRAMM SPACE HARDCODED TO 0x8000000+2 pages and 0x8c00000+1 pages
//
pdirectory* vmem_new_space_dir(pdirectory *copy_dir,bool stack_only)
{
x86_paging_disable(); //TODO: do not disable
pdirectory* dir = vmem_clean_dir();
// identity mapping for first blocks
uint32_t phys_addr=0;
uint32_t virt_addr=0;
kernel_pages=8; //32megs
// first pages are identity mapped
for(int j=0;j<kernel_pages;j++)
{
// this is the table for our page directory. It maps 1024*4096 bytes
ptable* table;
// create new tables on init
if(copy_dir==NULL)
{
// alloc space for our new table
table = (ptable*) kballoc(1);
if (!table)kpanic("unable to alloc table");
//! idenitity mapping
for (int i=0, frame=phys_addr, virt=virt_addr; i<1024; i++, frame+=4096, virt+=4096)
{
//! create a new page
pt_entry page=0;
pt_entry_add_attrib (&page, I86_PTE_PRESENT);
pt_entry_add_attrib (&page, I86_PTE_WRITABLE);
pt_entry_add_attrib (&page, I86_PTE_USER);
pt_entry_set_frame (&page, frame);
//! ...and add it to the page table
table->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
}
pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt_addr) ];
*entry=0;
pd_entry_add_attrib (entry, I86_PDE_PRESENT);
pd_entry_add_attrib (entry, I86_PDE_WRITABLE);
pt_entry_add_attrib (entry, I86_PTE_USER);
pd_entry_set_frame (entry, (physical_addr)table);
}
// otherwise simply take existing stuff from pdir 0
else
{
dir->m_entries[PAGE_DIRECTORY_INDEX(virt_addr)]=
copy_dir->m_entries[PAGE_DIRECTORY_INDEX(virt_addr)];
}
phys_addr+=1024*4096;
virt_addr+=1024*4096;
}
// FRAMEBUFFER IDENTITY MAP (4pages enought? )
phys_addr=fb_addr;
virt_addr=fb_addr;
if(fb_addr>0x100000)
for(int j=0;j<4;j++)
{
// this is the table for our page directory. It maps 1024*4096 bytes
ptable* table;
// create new tables on init
if(copy_dir==NULL)
{
// alloc space for our new table
table = (ptable*) kballoc(1);
if (!table)kpanic("unable to alloc table");
//! idenitity mapping
for (int i=0, frame=phys_addr, virt=virt_addr; i<1024; i++, frame+=4096, virt+=4096)
{
//! create a new page
pt_entry page=0;
pt_entry_add_attrib (&page, I86_PTE_PRESENT);
pt_entry_add_attrib (&page, I86_PTE_WRITABLE);
pt_entry_add_attrib (&page, I86_PTE_USER);
pt_entry_set_frame (&page, frame);
//! ...and add it to the page table
table->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
}
pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt_addr) ];
*entry=0;
pd_entry_add_attrib (entry, I86_PDE_PRESENT);
pd_entry_add_attrib (entry, I86_PDE_WRITABLE);
pt_entry_add_attrib (entry, I86_PTE_USER);
pd_entry_set_frame (entry, (physical_addr)table);
}
// otherwise simply take existing stuff from pdir 0
else
{
dir->m_entries[PAGE_DIRECTORY_INDEX(virt_addr)]=
copy_dir->m_entries[PAGE_DIRECTORY_INDEX(virt_addr)];
}
phys_addr+=1024*4096;
virt_addr+=1024*4096;
}
// 2 pages for apic ( in case on boundary??)
phys_addr=apic_addr;
virt_addr=apic_addr;
for(int j=0;j<2;j++)
{
// this is the table for our page directory. It maps 1024*4096 bytes
ptable* table;
// create new tables on init
if(copy_dir==NULL)
{
// alloc space for our new table
table = (ptable*) kballoc(1);
if (!table)kpanic("unable to alloc table");
//! idenitity mapping
for (int i=0, frame=phys_addr, virt=virt_addr; i<1024; i++, frame+=4096, virt+=4096)
{
//! create a new page
pt_entry page=0;
pt_entry_add_attrib (&page, I86_PTE_PRESENT);
pt_entry_add_attrib (&page, I86_PTE_WRITABLE);
pt_entry_add_attrib (&page, I86_PTE_USER);
pt_entry_set_frame (&page, frame);
//! ...and add it to the page table
table->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
}
pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt_addr) ];
*entry=0;
pd_entry_add_attrib (entry, I86_PDE_PRESENT);
pd_entry_add_attrib (entry, I86_PDE_WRITABLE);
pt_entry_add_attrib (entry, I86_PTE_USER);
pd_entry_set_frame (entry, (physical_addr)table);
}
// otherwise simply take existing stuff from pdir 0
else
{
dir->m_entries[PAGE_DIRECTORY_INDEX(virt_addr)]=
copy_dir->m_entries[PAGE_DIRECTORY_INDEX(virt_addr)];
}
phys_addr+=1024*4096;
virt_addr+=1024*4096;
}
// 2 pages for ioapic ( in case on boundary??)
phys_addr=io_apic_addr;
virt_addr=io_apic_addr;
for(int j=0;j<2;j++)
{
// this is the table for our page directory. It maps 1024*4096 bytes
ptable* table;
// create new tables on init
if(copy_dir==NULL)
{
// alloc space for our new table
table = (ptable*) kballoc(1);
if (!table)kpanic("unable to alloc table");
//! idenitity mapping
for (int i=0, frame=phys_addr, virt=virt_addr; i<1024; i++, frame+=4096, virt+=4096)
{
//! create a new page
pt_entry page=0;
pt_entry_add_attrib (&page, I86_PTE_PRESENT);
pt_entry_add_attrib (&page, I86_PTE_WRITABLE);
pt_entry_add_attrib (&page, I86_PTE_USER);
pt_entry_set_frame (&page, frame);
//! ...and add it to the page table
table->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
}
pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt_addr) ];
*entry=0;
pd_entry_add_attrib (entry, I86_PDE_PRESENT);
pd_entry_add_attrib (entry, I86_PDE_WRITABLE);
pt_entry_add_attrib (entry, I86_PTE_USER);
pd_entry_set_frame (entry, (physical_addr)table);
}
// otherwise simply take existing stuff from pdir 0
else
{
dir->m_entries[PAGE_DIRECTORY_INDEX(virt_addr)]=
copy_dir->m_entries[PAGE_DIRECTORY_INDEX(virt_addr)];
}
phys_addr+=1024*4096;
virt_addr+=1024*4096;
}
// programm space
virt_addr=0x8000000;
for(int j=0;j<2;j++)
{
if(stack_only)
{
dir->m_entries[PAGE_DIRECTORY_INDEX(virt_addr)]=
copy_dir->m_entries[PAGE_DIRECTORY_INDEX(virt_addr)];
virt_addr+=1024*4096;
continue;
}
ptable* table = (ptable*) kballoc (1);
pd_entry *oldentry=NULL;
ptable* oldtable=NULL;
if(copy_dir!=NULL)
{
oldentry=&(copy_dir->m_entries[PAGE_DIRECTORY_INDEX(virt_addr)]);
oldtable=pd_entry_get_frame(oldentry);
}
klog("oldtable at: 0x%08X",oldtable);
if (!table)kpanic("unable to alloc table");
klog("alloc table: %08X",table);
for (int i=0, virt=virt_addr; i<1024; i++, virt+=4096)
{
//klog("i = %d",i);
phys_addr=mem_alloc_block(); // get free space from the memory manager
if (!phys_addr)kpanic("unable to alloc spce for frame");
// if this is not init , copy contents from current space!
if(copy_dir!=NULL)
{
uint32_t addr_old=pt_entry_get_frame(&oldtable->m_entries[PAGE_TABLE_INDEX(virt)]);
//klog("physical memcpy(0x%08X,0x%08X,4096)",phys_addr, addr_old);
memcpy(phys_addr,addr_old,4096);
}
uint32_t frame=phys_addr;
//! create a new page
pt_entry page=0;
pt_entry_add_attrib (&page, I86_PTE_PRESENT);
pt_entry_add_attrib (&page, I86_PTE_WRITABLE);
pt_entry_add_attrib (&page, I86_PTE_USER);
pt_entry_set_frame (&page, frame);
//! ...and add it to the page table
table->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
}
pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt_addr) ];
*entry=0;
pd_entry_add_attrib (entry, I86_PDE_PRESENT);
pd_entry_add_attrib (entry, I86_PDE_WRITABLE);
pt_entry_add_attrib (entry, I86_PTE_USER);
pd_entry_set_frame (entry, (physical_addr)table);
virt_addr+=1024*4096;
}
// programm space : stack?
virt_addr=0x8c00000;
for(int j=0;j<1;j++)
{
ptable* table = (ptable*) kballoc (1);
pd_entry *oldentry=NULL;
ptable* oldtable=NULL;
if(copy_dir!=NULL)
{
oldentry=&(copy_dir->m_entries[PAGE_DIRECTORY_INDEX(virt_addr)]);
oldtable=pd_entry_get_frame(oldentry);
}
klog("oldtable at: 0x%08X",oldtable);
if (!table)kpanic("unable to alloc table");
klog("alloc table: %08X",table);
for (int i=0, virt=virt_addr; i<1024; i++, virt+=4096)
{
phys_addr=mem_alloc_block(); // get free space from the memory manager
if (!phys_addr)kpanic("unable to alloc spce for frame");
// if this is not init , copy contents from current space!
if(copy_dir!=NULL)
{
uint32_t addr_old=pt_entry_get_frame(&oldtable->m_entries[PAGE_TABLE_INDEX(virt)]);
//klog("physical memcpy(0x%08X,0x%08X,4096)",phys_addr, addr_old);
memcpy(phys_addr,addr_old,4096);
}
uint32_t frame=phys_addr;
//! create a new page
pt_entry page=0;
pt_entry_add_attrib (&page, I86_PTE_PRESENT);
pt_entry_add_attrib (&page, I86_PTE_WRITABLE);
pt_entry_add_attrib (&page, I86_PTE_USER);
pt_entry_set_frame (&page, frame);
//! ...and add it to the page table
table->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
}
pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt_addr) ];
*entry=0;
pd_entry_add_attrib (entry, I86_PDE_PRESENT);
pd_entry_add_attrib (entry, I86_PDE_WRITABLE);
pt_entry_add_attrib (entry, I86_PTE_USER);
pd_entry_set_frame (entry, (physical_addr)table);
virt_addr+=1024*4096;
}
if(copy_dir==NULL) // this happens only on init
{
klog("initializing virtual memory (paging)");
x86_set_page_directory(dir);
}
x86_paging_enable();
return dir;
}
void vmem_init(multiboot_information *cfg_multiboot, acpi_information *cfg_acpi)
{
fixme("do not share fb_addr with syscalls like that!");
fb_addr=cfg_multiboot->framebuffer_addr;
apic_addr=cfg_acpi->local_apic_address;
io_apic_addr=cfg_acpi->io_apic_address;
}
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