feat: ajout d'un bitmap pour la gestion fine de la mémoire physique libre

include/memory.h

@@ -3,8 +3,12 @@
 /*                                                                             */
 #include "types.h"
 
+#define TOPAGE(addr)	  (addr) >> 12
+
+
 #define	PAGESIZE 	4096 /* Taille d'une page */
 #define	PAGENUMBER 	1024 /* Nombre de pages */
+#define KERNELSIZE  PAGESIZE*PAGENUMBER*2 /* 2 pages de 4mo en identity mapping */
 
 #define IDT_ADDR		  0x00000000	/* adresse de la IDT */
 #define GDT_ADDR		  0x00000800	/* adresse de la GDT */
@@ -12,6 +16,10 @@
 #define	KERNEL_STACK_ADDR 0x0009FFFF    /* adresse de la pile du kernel */
 #define	KERNEL_CODE_ADDR  0x00100000
 
+/* limites de la mémoire 32 bits */
+#define	MAXMEMSIZE	0x100000000
+#define	MAXMEMPAGE	1024*1024
+
 /* page directory */
 #define PAGE_PRESENT	0b000000001/* page directory / table */
 #define PAGE_WRITE	    0b000000010 /* page lecture ecriture */

include/multiboot2.h

@@ -392,7 +392,7 @@
 u32 getgrubinfo(u8 type);
 u8 *getgrubinfo_cmdline(void);
 u32 getgrubinfo_ram(void);
-struct multiboot_memory_map_t *getgrubinfo_mem(void);
+struct multiboot_tag_mmap *getgrubinfo_mem(void);
 struct multiboot_tag_framebuffer *getgrubinfo_fb(void);
 void getgrubinfo_all(void);
 void initmultiboot(const u32 addr);

lib/memory.c

@@ -3,10 +3,121 @@
 /*                                                                             */
 #include "types.h"
 #include "memory.h"
+#include "multiboot2.h"
 
-u32 *pd0 = (u32 *) KERNEL_PGD_ADDR;	  /* page directory */
+static u32 *pd0 = (u32 *) KERNEL_PGD_ADDR;	  /* page directory */
-u8 *pg0 = (u8 *) 0;		              /* page 0 */
+static u8 *pg0 = (u8 *) 0;		              /* page 0 */
-u8 *pg1 = (u8 *) (PAGESIZE*PAGENUMBER); /* page 1 */
+static u8 *pg1 = (u8 *) (PAGESIZE*PAGENUMBER); /* page 1 */
+static u8 bitmap[MAXMEMPAGE / 8];
+
+/*******************************************************************************/ 
+/* Retourne la taille de la mémoire (selon grub) */ 
+
+u64 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 actuelle est occupée */ 
+
+void bitmap_page_use(page)
+{
+	bitmap[((u32) page)/8] |= (1 << (((u32) page)%8));
+}
+
+/*******************************************************************************/ 
+/* Retourne que la page actuelle est libre */ 
+
+void bitmap_page_free(page)
+{
+	bitmap[((u32) page)/8] &= ~(1 << (((u32) page)%8));
+}
+
+/*******************************************************************************/ 
+/* Reserve un espace mémoire dans le bitmap */ 
+
+void bitmap_page_setused(u64 addr,u64 len)
+{
+    u32 nbpage=TOPAGE(len);
+    u32 pagesrc=TOPAGE(addr);
+    if (len & 0b1111111111 > 0)
+        nbpage++;
+    for(u32 page=pagesrc;page<pagesrc+nbpage;page++)
+        bitmap_page_use(page);
+}
+
+/*******************************************************************************/ 
+/* Indique un espace mémoire libre dans le bitmap */ 
+
+void bitmap_page_setfree(u64 addr,u64 len)
+{
+    u32 nbpage=TOPAGE(len);
+    u32 pagesrc=TOPAGE(addr);
+    if (len & 0b1111111111 > 0)
+        nbpage++;
+    for(u32 page=pagesrc;page<pagesrc+nbpage;page++)
+        bitmap_page_free(page);
+}
+
+/*******************************************************************************/ 
+/* Retourne une page libre */ 
+
+u8* bitmap_page_getonefree(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;
+					bitmap_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 */
+ 
+void bitmap_init()
+{
+    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) 
+            bitmap_page_setfree(mmap->addr,mmap->len);
+        else
+            bitmap_page_setused(mmap->addr,mmap->len);
+    bitmap_page_setused(0x0,KERNELSIZE);
+}
 
 /*******************************************************************************/ 
 /* Initialisation de la mémoire paginée */ 

lib/multiboot.c

@@ -48,9 +48,9 @@ u32 getgrubinfo_ram(void)
 /*******************************************************************************/
 /* Renvoie le plan de la mémoire */
 
-struct multiboot_memory_map_t *getgrubinfo_mem(void)
+struct multiboot_tag_mmap *getgrubinfo_mem(void)
 {
-    struct multiboot_memory_map_t *tag=getgrubinfo(MULTIBOOT_TAG_TYPE_MMAP);
+    struct multiboot_tag_mmap *tag=getgrubinfo(MULTIBOOT_TAG_TYPE_MMAP);
     return tag;
 }
 

lib/video.c

@@ -1183,7 +1183,7 @@ u32 format(const u8 * string, va_list args, u32 maxsize, u32 (*fonction)(u8* src
 				bufferend=sitoa(num, &buffer, sizes[asize]);
                 buffersize=bufferend-&buffer[0];
 				counter += fonction(&buffer,&dest,buffersize);
-				counter += fonction(units[unit],&dest,3);
+				counter += fonction(&units[unit],&dest,3);
 				flag = false;
 				break;
 			case 'd':

makefile

@@ -79,13 +79,13 @@ qemu-debug:
 	(killall qemu-system-i386;qemu-system-i386 -m 1G -drive format=raw,file=./final/harddisk.img.final -s -S &)
 
 qemu-debug64:
-	(killall qemu-system-x86_64;qemu-system-x86_64 -m 1G -drive format=raw,file=./final/harddiskuefi.img.final --bios /usr/share/qemu/OVMF.fd -s -S &)
+	(killall qemu-system-x86_64;qemu-system-x86_64 -m 5G -drive format=raw,file=./final/harddiskuefi.img.final --bios /usr/share/qemu/OVMF.fd -s -S &)
 
 qemu:
 	(killall qemu-system-i386;qemu-system-i386 -m 1G -drive format=raw,file=./final/harddisk.img.final --enable-kvm -cpu host -s &)  
 
 qemu64:
-	(killall qemu-system-x86_64;qemu-system-x86_64 -m 1G -drive format=raw,file=./final/harddiskuefi.img.final --bios /usr/share/qemu/OVMF.fd --enable-kvm -cpu host -s &)  
+	(killall qemu-system-x86_64;qemu-system-x86_64 -m 5G -drive format=raw,file=./final/harddiskuefi.img.final --bios /usr/share/qemu/OVMF.fd --enable-kvm -cpu host -s &)  
 
 qemu-floppy:
 	(killall qemu-system-i386;qemu-system-i386 -m 1G -fda ./final/floppy.img.final --enable-kvm -cpu host -s &)  

system/system.c

@@ -69,6 +69,7 @@ int main(u32 magic, u32 addr)
 	ok();
 
     print("\033[37m\033[0m -Initilisation de la pagination (PAGING)");
+    bitmap_init();
 	//initpaging();
 	ok();