map user space and load data

fsdir/Programs/src/syscall.S

@@ -15,8 +15,12 @@ name:   PUSHL	%EBX          ;\
 	RET
 
 /* the system call library wrappers */
+DO_CALL(sys_read,1)
 DO_CALL(sys_write,2)
-DO_CALL(sys_halt,1)
+DO_CALL(sys_open,3)
+DO_CALL(sys_close,4)
+DO_CALL(sys_exec,5)
+DO_CALL(sys_exit,6)
 
 
 
@@ -28,5 +32,5 @@ _start:
     PUSHL   $0
     PUSHL   $0
 	PUSHL	%EAX
-	CALL	sys_halt
+	CALL	sys_exit
 

kernel/Devices/Storage/ext2.c

@@ -40,13 +40,13 @@ uint32_t ext2_read_data(uint32_t inode_num, uint32_t count, uint16_t* buf)
 	if (!buf)
 		return -1;
 
-	if (!count)
-		return 0;
-
 	inode_t inode;
 	ext2_get_inode(inode_num, &inode);
 
 	uint32_t blocks_left = count;
+	// pass in 0 to load the whole file
+	if (blocks_left == 0)
+		blocks_left = (inode.sectors_used + 1) / 2;
 
 	int i;
 	for (i = 0; i < 12 && blocks_left != 0; i++) {
@@ -174,8 +174,10 @@ uint32_t ext2_parse_path_to_inode_num(int8_t* filename)
 
 		inode = ext2_find_inode_num2(filename, inode);
 
-		if (!inode)
+		if (!inode) {
 			printf("File not found: %s\n", filename);
+			return inode;
+		}
 
 		// so now we got the inode of the first folder.
 

kernel/Interrupts/handlers.S

@@ -306,4 +306,8 @@ sys_call_table:
 .long 0
 .long sys_read
 .long sys_write
+.long sys_open
+.long sys_close
+.long sys_exec
+.long sys_exit
 

kernel/Syscalls/execute.c

+#include <types.h>
+#include <lib.h>
+#include <Devices/Storage/ext2.h>
+#include <paging.h>
+
+#include "execute.h"
+
+// TEMPORARY!!!
+static uint32_t pid = 0;
+
+int32_t _sys_exec(uint8_t* name)
+{
+	printf("In _sys_exec\n");
+
+
+	union {
+		uint16_t data16[512];
+		uint8_t data8[1024];
+	} data;
+
+	uint32_t parsed_inode = ext2_parse_path_to_inode_num((int8_t*)name);
+
+	if (!parsed_inode)
+		return -EXEC_NOT_FOUND;
+
+	ext2_read_data(parsed_inode, 1, data.data16);
+
+	if (data.data8[EI_MAG0] != ELFMAG0) return EXEC_NOT_ELF;
+	if (data.data8[EI_MAG1] != ELFMAG1) return EXEC_NOT_ELF;
+	if (data.data8[EI_MAG2] != ELFMAG2) return EXEC_NOT_ELF;
+	if (data.data8[EI_MAG3] != ELFMAG3) return EXEC_NOT_ELF;
+
+
+	elf_header_t* header = (elf_header_t*)data.data8;
+
+	map_large(EXEC_BASE_ADDR, _8MB + pid * _4MB);
+	ext2_read_data(parsed_inode, 0, (uint16_t*)EXEC_LOAD_ADDR);
+
+	printf("Some code for you: ");
+	int i;
+	for (i = 0; i < 16; i++) {
+		printf("%x ", *((uint8_t*)(header->e_entry) + i));
+	}
+	printf("\n");
+
+	return 1;
+}
+
+int32_t _sys_exit()
+{
+	printf("in _sys_exit\n");
+	return -1;
+}

kernel/Syscalls/execute.h

@@ -3,6 +3,12 @@
 
 #include <types.h>
 
+#define EXEC_NOT_FOUND	-1
+#define EXEC_NOT_ELF	-2
+
+#define EXEC_BASE_ADDR	0x08000000
+#define EXEC_LOAD_ADDR	0x08048000
+
 #define ET_NONE 0
 #define ET_REL	1
 #define ET_EXEC	2
@@ -60,5 +66,7 @@ typedef struct {
         uint16_t e_shstrndx;
 } elf_header_t;
 
+int32_t _sys_exec(uint8_t* name);
+int32_t _sys_exit();
 
 #endif
\ No newline at end of file

kernel/Syscalls/syscalls.c

@@ -2,6 +2,7 @@
 #include <lib.h>
 
 #include "syscalls.h"
+#include "execute.h"
 
 int32_t sys_read(int32_t fd, const void* buf, int32_t len)
 {
@@ -13,4 +14,23 @@ int32_t sys_write(int32_t fd, const void* buf, int32_t len)
 {
 	printf("syswrite\n");
 	return -1;
+}
+
+int32_t sys_open(uint8_t* name)
+{
+	return -1;
+}
+
+int32_t sys_close(int32_t fd)
+{
+	return -1;
+}
+
+int32_t sys_exec(uint8_t* name) 
+{
+	return _sys_exec(name);
+}
+
+int32_t sys_exit() {
+	return _sys_exit();
 }
\ No newline at end of file

kernel/Syscalls/syscalls.h

@@ -3,9 +3,19 @@
 
 #include <types.h>
 
-
+#define SYS_INVALID 0
+#define SYS_READ 1
+#define SYS_WRITE 2
+#define SYS_OPEN 3
+#define SYS_CLOSE 4
+#define SYS_EXEC 5
+#define SYS_EXIT 6
 
 int32_t sys_read(int32_t fd, const void* buf, int32_t len);
 int32_t sys_write(int32_t fd, const void* buf, int32_t len);
+int32_t sys_open(uint8_t* name);
+int32_t sys_close(int32_t fd);
+int32_t sys_exec(uint8_t* name);
+int32_t sys_exit();
 
 #endif

kernel/kernel.c

@@ -11,7 +11,7 @@
 #include "Devices/Storage/ext2.h"
 #include "paging.h"
 
-#include "Syscalls/execute.h"
+#include "Syscalls/syscalls.h"
 
 #define MORE_DEBUG 0
 
@@ -101,7 +101,7 @@ void entry(unsigned long magic, unsigned long addr) {
 	uint32_t fb_addr = mbi->framebuffer_info.framebuffer_addr_low;
 
 	init_paging();
-	map_large(fb_addr, fb_addr);
+	kmap_large(fb_addr, fb_addr);
 
 	printf("Does this work?\n");
 
@@ -120,30 +120,10 @@ void entry(unsigned long magic, unsigned long addr) {
 	ext2_init(mbr.partitions[0].lba_start);
 
 
-	union {
-		uint16_t data16[512];
-		uint8_t data8[1024];
-	} data;
-
-
-	printf("Going to read some stuff.\n");
-
-	uint32_t parsed_inode = ext2_parse_path_to_inode_num("/Programs/bin/hello");
-	printf("Parsed inode: %x\n", parsed_inode);
-	ext2_read_data(parsed_inode, 1, data.data16);
-	printf("Data: %s\n", data.data8);
-
-	elf_header_t* header = (elf_header_t*)data.data8;
-
-	printf("elf type: %x\n", header->e_type);
-	printf("elf machine: %x\n", header->e_machine);
-	printf("elf flags: %x\n", header->e_flags);
-	printf("elf entry: %x\n", header->e_entry);
-
-	asm volatile("		\n\
-		mov $2, %eax	\n\
-		int $0x80	\n\
-		");
+	int32_t error = sys_exec((uint8_t*)"/Programs/bin/hello");
+	if (error) {
+		printf("Error executing file: %d\n", error);
+	}
 	
 
 	while (1) {

kernel/lib.h

@@ -6,6 +6,10 @@
 
 #define CHECK_FLAG(flags, bit)   ((flags) & (1 << (bit)))
 
+#define _4MB 0x400000
+#define _8MB 0x800000
+
+
 typedef struct bmp {
 	union {
 		struct {

kernel/paging.c

@@ -64,6 +64,7 @@ int32_t kmap_large(uint32_t v_addr, uint32_t p_addr)
 	
 	page_directory[dir_index].present = 1;
 	page_directory[dir_index].rw = 1;
+	page_directory[dir_index].us = 0;
 	page_directory[dir_index].ps = 1;
 	page_directory[dir_index].g = 1;
 	PDIR_SET_ADDR(dir_index, p_addr);