Various adjustments to load external elf

Makefile

@@ -58,6 +58,7 @@ examples:
 	mkdir -p $(BUILD_FOLDER)/examples
 	${ASM_COMPILER} -g -felf64 -Fdwarf examples/example_syscall.s -o $(BUILD_FOLDER)/examples/example_syscall.o
 	$(X_LD) -g $(BUILD_FOLDER)/examples/example_syscall.o -o $(BUILD_FOLDER)/examples/example_syscall.elf -e loop -T examples/linker_script_$(SMALL_PAGES).ld
+	#ld --section-alignment 0x200000 -g $(BUILD_FOLDER)/examples/example_syscall.o -o $(BUILD_FOLDER)/examples/example_syscall.elf -e loop
 
 debug: DEBUG=1
 debug: CFLAGS += $(C_DEBUG_FLAGS)
@@ -67,7 +68,7 @@ debug: $(BUILD_FOLDER)/$(ISO_IMAGE_FILENAME)
 	# qemu-system-x86_64 -monitor unix:qemu-monitor-socket,server,nowait -cpu qemu64,+x2apic  -cdrom $(BUILD_FOLDER)/$(ISO_IMAGE_FILENAME) -serial file:dreamos64.log -m 1G -d int -no-reboot -no-shutdown
 	$(QEMU_SYSTEM) -monitor unix:qemu-monitor-socket,server,nowait -cpu qemu64,+x2apic  -cdrom $(BUILD_FOLDER)/$(ISO_IMAGE_FILENAME) -serial stdio -m 2G  -no-reboot -no-shutdown
 
-$(BUILD_FOLDER)/$(ISO_IMAGE_FILENAME): examples $(BUILD_FOLDER)/kernel.bin grub.cfg
+$(BUILD_FOLDER)/$(ISO_IMAGE_FILENAME): $(BUILD_FOLDER)/kernel.bin grub.cfg examples
 	mkdir -p $(BUILD_FOLDER)/isofiles/boot/grub
 	cp grub.cfg $(BUILD_FOLDER)/isofiles/boot/grub
 	cp $(BUILD_FOLDER)/kernel.bin $(BUILD_FOLDER)/isofiles/boot
@@ -109,7 +110,7 @@ tests:
 	${TOOLCHAIN} ${TESTFLAGS} tests/test_kheap.c tests/test_common.c src/kernel/mem/kheap.c src/kernel/mem/bitmap.c src/kernel/mem/pmm.c src/kernel/mem/mmap.c src/kernel/mem/vmm_util.c -o tests/test_kheap.o
 	${TOOLCHAIN} ${TESTFLAGS} tests/test_vm.c tests/test_common.c src/kernel/arch/x86_64/system/vm.c src/kernel/mem/vmm_util.c  -o tests/test_vm.o
 	${TOOLCHAIN} ${TESTFLAGS} tests/test_vfs.c tests/test_common.c src/fs/vfs.c src/drivers/fs/ustar.c -o tests/test_vfs.o
-	${TOOLCHAIN} ${TESTFLAGS} tests/test_utils.c src/kernel/mem/vmm_util.c -o tests/test_utils.o
+	${TOOLCHAIN} ${TESTFLAGS} tests/test_utils.c tests/test_common.c  src/kernel/mem/vmm_util.c -o tests/test_utils.o
 	${TOOLCHAIN} ${TESTFLAGS} tests/test_window.c tests/test_common.c  src/kernel/graphics/window.c -o tests/test_window.o
 	./tests/test_mem.o && ./tests/test_kheap.o && ./tests/test_number_conversion.o && ./tests/test_vm.o && ./tests/test_vfs.o && ./tests/test_utils.o && ./tests/test_window.o
 

docs/kernel/Syscalls.md

@@ -4,7 +4,7 @@ The syscalls are called using the interrupt vector `0x80`. Arguments depend on t
 
 # Syscalls List
 
-## 0x01 TEST
+## 0x00 TEST
 
 The first syscall is reserved for test purpose, and it should be never used.
 

src/include/kernel/mem/vmm_util.h

@@ -20,6 +20,7 @@
 size_t get_number_of_pages_from_size(size_t size);
 size_t align_value_to_page(size_t value);
 size_t align_up(size_t value, size_t alignment);
+size_t align_down(size_t value, size_t alignment);
 bool is_address_aligned(size_t value, size_t alignment);
 
 size_t vm_parse_flags( size_t flags );

src/kernel/arch/x86_64/mem/vmm_mapping.c

@@ -24,7 +24,7 @@ void *map_phys_to_virt_addr_hh(void* physical_address, void* address, size_t fla
     uint8_t user_mode_status = 0;
 
     if ( !is_address_higher_half((uint64_t) address) ) {
-        pretty_log(Verbose, "address is in lower half");
+        pretty_logf(Verbose, "address is in lower half: 0x%x", address);
         flags = flags | VMM_FLAGS_USER_LEVEL;
         user_mode_status = VMM_FLAGS_USER_LEVEL;
     }
@@ -84,7 +84,7 @@ void *map_phys_to_virt_addr_hh(void* physical_address, void* address, size_t fla
         }
 #elif SMALL_PAGES == 0
             pd_root[pd_e] = (uint64_t) (physical_address) | HUGEPAGE_BIT | flags | user_mode_status;
-            pretty_logf(Verbose, " PD Flags: 0x%x entry value pd_root[0x%x]: 0x%x", flags, pd_e, pd_root[pd_e]);
+            pretty_logf(Verbose, " PD Flags: 0x%x entry value pd_root[0x%x]: 0x%x - address: 0x%x", flags, pd_e, pd_root[pd_e], address);
             return address;
         }
 #endif

src/kernel/loaders/elf.c

@@ -23,7 +23,7 @@ void load_elf(uintptr_t elf_start, uint64_t size) {
             Elf64_Phdr *cur_phdr = read_phdr(elf_header, 0);
             pretty_logf(Verbose, "\t[cur_phdr]: Type: 0x%x, Flags: 0x%x  -  Vaddr: 0x%x - aligned: 0x%x  - p_align: 0x%x - p_memsz: 0%x - p_offset: 0x%x", cur_phdr->p_type, cur_phdr->p_flags, cur_phdr->p_vaddr, align_value_to_page(cur_phdr->p_vaddr), cur_phdr->p_align, cur_phdr->p_memsz, cur_phdr->p_offset);
             cur_phdr = read_phdr(elf_header, 1);
-            pretty_logf(Verbose, "\t[cur_phdr]: Type: 0x%x, Flags: 0x%x  -  Vaddr: 0x%x - aligned: 0x%x  - p_align: 0x%x - p_memsz: 0%x - p_offset: 0x%x", cur_phdr->p_type, cur_phdr->p_flags, cur_phdr->p_vaddr, align_value_to_page(cur_phdr->p_vaddr), cur_phdr->p_align, cur_phdr->p_memsz, cur_phdr->p_offset);
+            //pretty_logf(Verbose, "\t[cur_phdr]: Type: 0x%x, Flags: 0x%x  -  Vaddr: 0x%x - aligned: 0x%x  - p_align: 0x%x - p_memsz: 0%x - p_offset: 0x%x", cur_phdr->p_type, cur_phdr->p_flags, cur_phdr->p_vaddr, align_value_to_page(cur_phdr->p_vaddr), cur_phdr->p_align, cur_phdr->p_memsz, cur_phdr->p_offset);
         }
     }
 }

src/kernel/main.c

@@ -266,8 +266,11 @@ void kernel_start(unsigned long addr, unsigned long magic){
     char a = 'a';
     task_t* idle_task = create_task_from_func("idle", idle, &a, true);
     idle_thread = idle_task->threads;
-    //task_t* userspace_task = create_task_from_func("userspace_idle", NULL, &a, false);
+    #if PAGE_SIZE_IN_BYTES == 0x200000
+    task_t* userspace_task = create_task_from_func("userspace_idle", NULL, &a, false);
+    #else
     task_t* elf_task = create_task_from_elf("elf_idle", NULL, (Elf64_Ehdr *) (uintptr_t) hhdm_get_variable(elf_module_start_phys));
+    #endif
     //create_thread("ledi", noop2, &c, eldi_task);
     //create_task("sleeper", noop3, &d);
     //execute_runtime_tests();

src/kernel/mem/vmm_util.c

@@ -13,6 +13,10 @@ size_t align_up(size_t value, size_t alignment) {
     return ((value + alignment - 1) / alignment) * alignment;
 }
 
+size_t align_down(size_t value, size_t alignment) {
+    return (value / alignment) * alignment;
+}
+
 bool is_address_aligned(size_t value, size_t alignment) {
     if (value % alignment == 0) {
         return true;

src/kernel/scheduling/task.c

@@ -61,6 +61,10 @@ task_t *create_task_from_elf(char *name, void *args, Elf64_Ehdr *elf_header){
             uint64_t vaddr_address = align_value_to_page(phdr.p_vaddr);
             for (int j = 0; j < mem_pages; j++) {
                 pretty_logf(Verbose, "[%d]: Mapping: offset: 0x%x (virtual: 0x%x) in vaddr: 0x%x", j, hhdm_get_phys_address((uintptr_t) offset_address), offset_address, vaddr_address);
+                if ( !is_address_aligned((size_t) hhdm_get_phys_address(offset_address), PAGE_SIZE_IN_BYTES)) {
+                    pretty_log(Fatal, "Error: module elf phys address is not page aligned");
+                }
+
                 map_phys_to_virt_addr_hh(hhdm_get_phys_address(offset_address), (void *) vaddr_address, VMM_FLAGS_USER_LEVEL | vmm_hdr_flags | VMM_FLAGS_PRESENT, (uint64_t *) new_task->vmm_data.root_table_hhdm);
                 //I need a mem copy. I need to fopy the content of elf_header + phdr.p_offset into phdr.p_vaddr
                 offset_address += (uint64_t) phdr.p_align;

src/kernel/scheduling/thread.c

@@ -42,7 +42,7 @@ thread_t* create_thread(char* thread_name, void (*_entry_point)(void *), void* a
         // This piece of code is temporary, just to test a userspace task, it run just an infinite loop.
         pretty_logf(Verbose, "vmm_data address: 0x%x", &(parent_task->vmm_data));
         if (is_elf ) {
-            pretty_logf(Verbose, "Preparing to launch an ELF. entry_pint = 0x%x", (uint64_t) _entry_point);
+            pretty_logf(Verbose, "Preparing to launch an ELF. entry_point = 0x%x", (uint64_t) _entry_point);
             new_thread->execution_frame->rip = (uint64_t)_entry_point;
         } else {
             new_thread->execution_frame->rip = prepare_userspace_function(&(parent_task->vmm_data));
@@ -75,7 +75,6 @@ thread_t* create_thread(char* thread_name, void (*_entry_point)(void *), void* a
           while(1);
     }
     // We need to allocate a new stack for each thread
-    //void* stack_pointer = kmalloc(THREAD_DEFAULT_STACK_SIZE);
     void* stack_pointer = vmm_alloc(THREAD_DEFAULT_STACK_SIZE, VMM_FLAGS_PRESENT | VMM_FLAGS_WRITE_ENABLE | VMM_FLAGS_STACK, &(parent_task->vmm_data));
     if (stack_pointer == NULL) {
         pretty_log(Fatal, "rsp is null - PANIC!");

tests/test_utils.c

@@ -1,17 +1,24 @@
+#include <test_common.h>
 #include <vmm_util.h>
 #include <assert.h>
 #include <stdio.h>
 
+void test_utils();
+
 int main() {
     printf("Testing VMM Utility function  -\n");
+    test_utils();
+}
+
+void test_utils() {
     size_t number_of_pages = get_number_of_pages_from_size(0x900);
-    printf("\t [test_utils] (get_number_of_pages_from_size): Testing number of pages for 0x900, should be 1: %ld\n", number_of_pages);
+    printf("\t[test_utils] (get_number_of_pages_from_size): Testing number of pages for 0x900, should be 1: %ld\n", number_of_pages);
     assert(number_of_pages == 1);
     number_of_pages = get_number_of_pages_from_size(0x0);
-    printf("\t [test_utils] (get_number_of_pages_from_size): Testing number of pages for 0x0, should be 0: %ld\n", number_of_pages);
+    printf("\t[test_utils] (get_number_of_pages_from_size): Testing number of pages for 0x0, should be 0: %ld\n", number_of_pages);
     assert(align_value_to_page(0x100) == 0x200000);
-    printf("\t [test_utils] (align_value_to_page): Testing alignment for 0x100, should be 0x200000: %lx\n", align_value_to_page(0x100));
+    printf("\t[test_utils] (align_value_to_page): Testing alignment for 0x100, should be 0x200000: %lx\n", align_value_to_page(0x100));
     assert(align_value_to_page(0x200015) == 0x400000);
-    printf("\t [test_utils] (align_value_to_page):  Testing alignment for 0x100, should be 0x200015: %lx\n", align_value_to_page(0x200015));
-
+    pretty_assert(0x200000, align_down(0x3c7000, 0x200000), ==, "Testing align_down");
+    pretty_assert(0x600000, align_down(0x6c7000, 0x200000), ==, "Testing align_down");
 }