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cos2000v2/lib/memory.c

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/*******************************************************************************/
/* COS2000 - Compatible Operating System - LGPL v3 - Hordé Nicolas */
/* */
#include "types.h"
#include "memory.h"
#include "multiboot2.h"
#include "queue.h"
#include "asm.h"
static pd *kerneldirectory=NULL; /* pointeur vers le page directory noyau */
static u8 *kernelheap=NULL; /* pointeur vers le heap noyau */
static u8 bitmap[MAXMEMPAGE / 8]; /* bitmap */
static vrange_t vrange_head;
/*******************************************************************************/
/* Erreur fatale */
void panic(u8 *string)
{
printf("KERNEL PANIC: %s\r\nSysteme arrete...\n");
halt();
}
/*******************************************************************************/
/* Alloue plusieurs pages virtuelles (size) pour le heap du noyau */
tmalloc *mallocpage(u8 size)
{
tmalloc *chunk;
u8 *paddr;
u32 realsize=size * PAGESIZE;
if ((kernelheap - KERNEL_HEAP + realsize) > MAXHEAPSIZE)
panic("Plus de memoire noyau heap disponible a allouer !\n");
chunk = (tmalloc *) kernelheap;
virtual_range_new_kernel(kernelheap, realsize);
chunk->size = realsize;
chunk->used = 0;
return chunk;
}
/*******************************************************************************/
/* Alloue de la mémoire virtuelle au noyau de façon dynamique (heap) */
void *vmalloc(u32 size)
{
u32 realsize;
tmalloc *chunk, *new;
realsize = sizeof(tmalloc) + size;
if (realsize < MALLOC_MINIMUM)
realsize = MALLOC_MINIMUM;
chunk = KERNEL_HEAP;
while (chunk->used || chunk->size < realsize) {
if (chunk->size == 0)
panic(sprintf("Element du heap %x defectueux avec une taille nulle (heap %x) !",chunk, kernelheap));
chunk = chunk + chunk->size;
if (chunk == (tmalloc *) kernelheap)
mallocpage((realsize / PAGESIZE) + 1);
else if (chunk > (tmalloc *) kernelheap)
panic (sprintf("Element du heap %x depassant la limite %x !",chunk, kernelheap));
}
if (chunk->size - realsize < MALLOC_MINIMUM)
chunk->used = 1;
else {
new = chunk + realsize;
new->size = chunk->size - realsize;
new->used = 0;
chunk->size = realsize;
chunk->used = 1;
}
return (u8 *) chunk + sizeof(tmalloc);
}
/*******************************************************************************/
/* Libère de la mémoire virtuelle depuis le heap noyau */
void vfree(void *vaddr)
{
tmalloc *chunk, *new;
chunk = (tmalloc *) (vaddr - sizeof(tmalloc));
chunk->used = 0;
while ((new = (tmalloc *) chunk + chunk->size) && new < (tmalloc *) kernelheap && new->used == 0)
chunk->size += new->size;
}
/*******************************************************************************/
/* Retourne la taille de la mémoire physique (selon grub) */
u64 physical_getmemorysize()
{
u64 maxaddr=0;
struct multiboot_tag_mmap *tag=getgrubinfo_mem();
multiboot_memory_map_t *mmap;
for (mmap = ((struct multiboot_tag_mmap *) tag)->entries;(u8 *) mmap < (u8 *) tag + tag->size; mmap = (multiboot_memory_map_t *)
((unsigned long) mmap + ((struct multiboot_tag_mmap *) tag)->entry_size))
if (mmap->addr+mmap->len>maxaddr)
maxaddr=mmap->addr+mmap->len;
return maxaddr;
}
/*******************************************************************************/
/* Retourne que la page physique actuelle est occupée */
void physical_page_use(u32 page)
{
bitmap[(page/8)] |= (1 << (page%8));
}
/*******************************************************************************/
/* Retourne que la page physique actuelle est libre */
void physical_page_free(u32 page)
{
bitmap[(page/8)] &= ~(1 << (page%8));
}
/*******************************************************************************/
/* Reserve un espace mémoire physique dans le bitmap */
void physical_range_use(u64 addr,u64 len)
{
u32 nbpage=TOPAGE(len);
u32 pagesrc=TOPAGE(addr);
if (len & 0b1111111111 > 0)
nbpage++;
if (addr>=MAXMEMSIZE)
return;
if (addr+len>=MAXMEMSIZE)
len=MAXMEMSIZE-addr-1;
for(u32 page=pagesrc;page<pagesrc+nbpage;page++)
physical_page_use(page);
}
/*******************************************************************************/
/* Libère un espace mémoire physique dans le bitmap */
void physical_range_free(u64 addr,u64 len)
{
u32 nbpage=TOPAGE(len);
u32 pagesrc=TOPAGE(addr);
if (len & 0b1111111111 > 0)
nbpage++;
if (addr>=MAXMEMSIZE)
return;
if (addr+len>=MAXMEMSIZE)
len=MAXMEMSIZE-addr-1;
for(u32 page=pagesrc;page<pagesrc+nbpage;page++)
physical_page_free(page);
}
/*******************************************************************************/
/* Retourne une page physique libre */
u8* physical_page_getfree(void)
{
u8 byte, bit;
u32 page = 0;
for (byte = 0; byte < sizeof(bitmap); byte++)
if (bitmap[byte] != 0xFF)
for (bit = 0; bit < 8; bit++)
if (!(bitmap[byte] & (1 << bit))) {
page = 8 * byte + bit;
physical_page_use(page);
return (u8 *) (page * PAGESIZE);
}
return NULL;
}
/*******************************************************************************/
/* Retourne l'espace libre */
u64 getmemoryfree(void)
{
u32 byte, bit;
u64 free = 0;
for (byte = 0; byte < sizeof(bitmap); byte++)
if (bitmap[byte] != 0xFF)
for (bit = 0; bit < 8; bit++)
if (!(bitmap[byte] & (1 << bit)))
free+=PAGESIZE;
return free;
}
/*******************************************************************************/
/* Initialisation du bitmap pour la gestion physique de la mémoire */
void physical_init(void)
{
u64 page;
for (page=0; page < sizeof(bitmap); page++)
bitmap[page] = 0xFF;
struct multiboot_tag_mmap *tag=getgrubinfo_mem();
multiboot_memory_map_t *mmap;
for (mmap = ((struct multiboot_tag_mmap *) tag)->entries;(u8 *) mmap < (u8 *) tag + tag->size; mmap = (multiboot_memory_map_t *)
((unsigned long) mmap + ((struct multiboot_tag_mmap *) tag)->entry_size))
if (mmap->type==1)
physical_range_free(mmap->addr,mmap->len);
else
physical_range_use(mmap->addr,mmap->len);
//physical_range_use(0x0,KERNELSIZE);
}
/*******************************************************************************/
/* Allocation de page virtuelle de mémoire */
page *virtual_page_getfree(void)
{
page *pg;
vrange *vpages;
u8 *vaddr, *paddr;
paddr = physical_page_getfree();
if (paddr == NULL)
panic ("Plus de memoire physique disponible !\n");
if (TAILQ_EMPTY(&vrange_head))
panic("Plus de place disponible dans la reserve de page !\n");
vpages = TAILQ_FIRST(&vrange_head);
vaddr = vpages->vaddrlow;
vpages->vaddrlow += PAGESIZE;
if (vpages->vaddrlow == vpages->vaddrhigh) {
TAILQ_REMOVE(&vrange_head, vpages, tailq);
vfree(vpages);
}
virtual_pd_page_add(kerneldirectory,vaddr,paddr, 0);
pg = (page*) vmalloc(sizeof(page));
pg->vaddr = vaddr;
pg->paddr = paddr;
return pg;
}
/*******************************************************************************/
/* Création d'un directory pour la gestion virtuelle de la mémoire */
pd *virtual_pd_create()
{
pd *new;
u32 *pdir,*pd0;
u32 i;
new = (pd *) vmalloc(sizeof(pd));
new->addr = virtual_page_getfree();
if (kerneldirectory!=NULL)
{
pdir = (u32 *) new->addr->vaddr;
pd0 = (u32 *) kerneldirectory->addr->vaddr;
for (i = 0; i < 256; i++)
pdir[i] = pd0[i];
for (i = 256; i < 1023; i++)
pdir[i] = 0;
pdir[1023] = ((u32) new->addr->paddr | (PAGE_PRESENT | PAGE_WRITE));
}
TAILQ_INIT(&new->page_head);
return new;
}
/*******************************************************************************/
/* Renvoie l'adresse physique de la page virtuel */
u8* virtual_to_physical(u8 *vaddr)
{
u32 *pdir;
u32 *ptable;
pdir = (u32 *) (0xFFFFF000 | (((u32) vaddr & 0xFFC00000) >> 20));
if ((*pdir & PAGE_PRESENT)) {
ptable = (u32 *) (0xFFC00000 | (((u32) vaddr & 0xFFFFF000) >> 10));
if ((*ptable & PAGE_PRESENT))
return (u8 *) ((*ptable & 0xFFFFF000) + (TOPG((u32) vaddr)));
}
return 0;
}
/*******************************************************************************/
/* Libère une page virtuelle de la mémoire */
void virtual_page_free(u8* vaddr)
{
vrange *next, *prev, *new;
u8 *paddr;
paddr = virtual_to_physical(vaddr);
if (paddr)
virtual_page_free(paddr);
else {
printf("Aucune page associee a l'adresse virtuelle %x\n", vaddr);
return;
}
virtual_pd_page_remove(vaddr);
TAILQ_FOREACH(next, &vrange_head, tailq) {
if (next->vaddrlow > vaddr)
break;
}
prev = TAILQ_PREV(next, vrange_s, tailq);
if (prev->vaddrhigh == vaddr) {
prev->vaddrhigh += PAGESIZE;
if (prev->vaddrhigh == next->vaddrlow) {
prev->vaddrhigh = next->vaddrhigh;
TAILQ_REMOVE(&vrange_head, next, tailq);
vfree(next);
}
}
else if (next->vaddrlow == vaddr + PAGESIZE) {
next->vaddrlow = vaddr;
}
else if (next->vaddrlow > vaddr + PAGESIZE) {
new = (vrange*) vmalloc(sizeof(vrange));
new->vaddrlow = vaddr;
new->vaddrhigh = vaddr + PAGESIZE;
TAILQ_INSERT_BEFORE(prev, new, tailq);
}
else
panic("Liste chainee corrompue !\n");
return 0;
}
/*******************************************************************************/
/* Destruction d'un directory pour la gestion virtuelle de la mémoire */
void virtual_pd_destroy(pd *dst)
{
page *pg;
TAILQ_FOREACH(pg, &dst->page_head, tailq) {
virtual_page_free(pg->vaddr);
TAILQ_REMOVE(&dst->page_head, pg, tailq);
vfree(pg);
}
virtual_page_free(dst->addr->vaddr);
vfree(dst);
return 0;
}
/*******************************************************************************/
/* Initialisation d'une STAILQ pour la gestion virtuelle de la mémoire */
void virtual_init(void)
{
kernelheap = (u8 *) KERNEL_HEAP;
vrange *vpages = (vrange*) vmalloc(sizeof(vrange));
vpages->vaddrlow = (u8 *) KERNEL_HEAP;
vpages->vaddrhigh = (u8 *) KERNEL_HEAP+MAXHEAPSIZE;
TAILQ_INIT(&vrange_head);
TAILQ_INSERT_TAIL(&vrange_head, vpages, tailq);
kerneldirectory=virtual_pd_create();
virtual_range_use_kernel(0x00000000, 0x00000000, KERNELSIZE);
}
/*******************************************************************************/
/* Initialisation de la mémoire paginée */
void initpaging(void)
{
physical_init();
virtual_init();
asm("mov %[directory_addr], %%eax \n \
mov %%eax, %%cr3 \n \
mov %%cr4, %%eax \n \
or $0x00000010, %%eax \n \
mov %%eax, %%cr4 \n \
mov %%cr0, %%eax \n \
or $0x80000001, %%eax \n \
mov %%eax, %%cr0"::[directory_addr]"m"(kerneldirectory->addr));
}
/*******************************************************************************/
/* Copie un octet une ou plusieurs fois en mémoire */
void memset(void *dst, u8 val, u32 count, u32 size)
{
u8 *d = (u8 *) dst;
if (size>0) size--;
for (; count != 0; count--) {
*(d++) = val;
d+=size;
}
}
/*******************************************************************************/
/* Copie une portion de mémoire vers une autre */
void memcpy(void *src, void *dst, u32 count, u32 size)
{
u8 *s = (u8 *) src;
u8 *d = (u8 *) dst;
if (size>0) size--;
for (; count != 0; count--) {
*(d++) = *(s++);
d+=size;
}
}
/*******************************************************************************/
/* Compare 2 portions de mémoire */
u32 memcmp(void *src, void *dst, u32 count, u32 size)
{
u8 *s = (u8 *) src;
u8 *d = (u8 *) dst;
if (size>0) size--;
for (; count != 0; count--) {
if (*(s++) != *(d++))
return *d - *s;
s+= size;
d+= size;
}
}
/*******************************************************************************/
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