replace nasm assembly with gcc/clang assembly; add hello_world binary with git lfs

.gitattributes

@@ -0,0 +1 @@
+src/kxos-user/hello_world/hello_world filter=lfs diff=lfs merge=lfs -text

src/kxos-frame/src/user.rs

@@ -111,6 +111,7 @@ impl<'a> UserMode<'a> {
         self.user_space.vm_space().activate();
         if !self.executed {
             self.current.syscall_frame().caller.rcx = self.user_space.cpu_ctx.gp_regs.rip as usize;
+            self.current.syscall_frame().callee.rsp = self.user_space.cpu_ctx.gp_regs.rsp as usize;
             self.executed = true;
         } else {
             if self.current.inner_exclusive_access().is_from_trap {
@@ -137,6 +138,7 @@ impl<'a> UserMode<'a> {
         } else {
             self.context = CpuContext::from(*self.current.syscall_frame());
             println!("[kernel] syscall id:{}",self.context.gp_regs.rax);
+            println!("[kernel] rsp: 0x{:x}", self.context.gp_regs.rsp);
             UserEvent::Syscall
         }
     }

src/kxos-std/src/memory/elf.rs

@@ -1,10 +1,11 @@
-use core::{ops::Range, cmp::Ordering};
+use core::{cmp::Ordering, ops::Range};
 
-use alloc::vec::Vec;
 use alloc::vec;
+use alloc::vec::Vec;
 use kxos_frame::{
-    vm::{Vaddr, VmAllocOptions, VmFrameVec, VmIo, VmPerm, VmSpace, VmMapOptions},
-    Error, config::PAGE_SIZE,
+    config::PAGE_SIZE,
+    vm::{Vaddr, VmAllocOptions, VmFrameVec, VmIo, VmMapOptions, VmPerm, VmSpace},
+    Error,
 };
 use xmas_elf::{
     header,
@@ -39,7 +40,7 @@ impl<'a> ElfSegment<'a> {
             Ok(type_) => type_,
         };
         let data = match read_segment_data(segment, elf_file) {
-            Err(_) => return Err(ElfError::from("")),
+            Err(msg) => return Err(ElfError::from(msg)),
             Ok(data) => data,
         };
         let vm_perm = Self::parse_segment_perm(segment)?;
@@ -58,7 +59,7 @@ impl<'a> ElfSegment<'a> {
         }
         let mut vm_perm = VmPerm::R;
         if flags.is_write() {
-            vm_perm |= VmPerm::W;        
+            vm_perm |= VmPerm::W;
         }
         if flags.is_execute() {
             vm_perm |= VmPerm::X;
@@ -188,8 +189,10 @@ impl<'a> ElfLoadInfo<'a> {
         for segment in self.segments.iter() {
             let start_address = segment.start_address();
             let len = segment.data.len();
-            let mut read_buffer = vec![0;len];
-            vm_space.read_bytes(start_address, &mut read_buffer).expect("read bytes failed");
+            let mut read_buffer = vec![0; len];
+            vm_space
+                .read_bytes(start_address, &mut read_buffer)
+                .expect("read bytes failed");
             let res = segment.data.cmp(&read_buffer);
             assert_eq!(res, Ordering::Equal);
         }
@@ -255,14 +258,17 @@ impl From<Error> for ElfError {
 fn read_segment_data<'a>(
     segment: ProgramHeader<'a>,
     elf_file: &ElfFile<'a>,
-) -> Result<&'a [u8], ()> {
+) -> Result<&'a [u8], &'static str> {
     match segment.get_data(&elf_file) {
-        Err(_) => Err(()),
+        Err(msg) => Err(msg),
         Ok(data) => {
-            if let SegmentData::Undefined(data) = data {
-                Ok(data)
-            } else {
-                Err(())
+            match data {
+                SegmentData::Note64(_, data) | SegmentData::Undefined(data) => {
+                    Ok(data)
+                },
+                _ => {
+                    Err("Unkonwn segment data type")
+                }
             }
         }
     }

src/kxos-std/src/memory/mod.rs

@@ -1,7 +1,7 @@
 pub mod elf;
 pub mod user_stack;
 pub mod vm_page;
-use kxos_frame::{vm::VmSpace, debug};
+use kxos_frame::{debug, vm::VmSpace};
 
 use self::elf::{ElfError, ElfLoadInfo};
 

src/kxos-std/src/process/mod.rs

@@ -2,7 +2,7 @@ use core::sync::atomic::{AtomicUsize, Ordering};
 
 use alloc::sync::Arc;
 // use kxos_frame::{sync::SpinLock, task::Task, user::UserSpace};
-use kxos_frame::{task::Task, debug};
+use kxos_frame::{debug, task::Task};
 
 use self::task::spawn_user_task_from_elf;
 
@@ -34,12 +34,19 @@ impl Process {
         }
     }
 
-    pub fn spawn_kernel_task<F>(task_fn: F) -> Self where F: Fn() + Send + Sync + 'static {
+    pub fn spawn_kernel_task<F>(task_fn: F) -> Self
+    where
+        F: Fn() + Send + Sync + 'static,
+    {
         let pid = new_pid();
-        debug!("pid = {}" , pid);
+        debug!("pid = {}", pid);
         let task = Task::spawn(task_fn, None::<u8>, None).expect("spawn kernel task failed");
         let exit_code = 0;
-        Self { pid, task, exit_code }
+        Self {
+            pid,
+            task,
+            exit_code,
+        }
     }
 }
 

src/kxos-std/src/process/task.rs

@@ -1,10 +1,9 @@
 use alloc::sync::Arc;
 use kxos_frame::{
     cpu::CpuContext,
-    println,
     task::Task,
     user::{UserEvent, UserMode, UserSpace},
-    vm::VmSpace,
+    vm::VmSpace, debug,
 };
 
 use crate::{memory::load_elf_to_vm_space, syscall::syscall_handler};
@@ -27,6 +26,7 @@ pub fn spawn_user_task_from_elf(elf_file_content: &[u8]) -> Arc<Task> {
         let mut user_mode = UserMode::new(user_space);
         loop {
             let user_event = user_mode.execute();
+            debug!("return from user mode");
             let context = user_mode.context_mut();
             if let HandlerResult::Exit = handle_user_event(user_event, context) {
                 // FIXME: How to set task status? How to set exit code of process?

src/kxos-std/src/syscall/mod.rs

@@ -1,4 +1,3 @@
-use alloc::ffi::CString;
 use alloc::vec;
 use alloc::{sync::Arc, vec::Vec};
 use kxos_frame::cpu::CpuContext;
@@ -12,7 +11,7 @@ use crate::process::task::HandlerResult;
 const SYS_WRITE: u64 = 1;
 const SYS_EXIT: u64 = 60;
 
-pub struct SyscallFrame {
+pub struct SyscallArgument {
     syscall_number: u64,
     args: [u64; 6],
 }
@@ -22,7 +21,7 @@ pub enum SyscallResult {
     Return(i32),
 }
 
-impl SyscallFrame {
+impl SyscallArgument {
     fn new_from_context(context: &CpuContext) -> Self {
         let syscall_number = context.gp_regs.rax;
         let mut args = [0u64; 6];
@@ -40,7 +39,7 @@ impl SyscallFrame {
 }
 
 pub fn syscall_handler(context: &mut CpuContext) -> HandlerResult {
-    let syscall_frame = SyscallFrame::new_from_context(context);
+    let syscall_frame = SyscallArgument::new_from_context(context);
     let syscall_return = syscall_dispatch(syscall_frame.syscall_number, syscall_frame.args);
 
     match syscall_return {
@@ -70,7 +69,7 @@ pub fn sys_write(fd: u64, user_buf_ptr: u64, user_buf_len: u64) -> SyscallResult
         let user_buffer =
             copy_bytes_from_user(user_space, user_buf_ptr as usize, user_buf_len as usize)
                 .expect("read user buffer failed");
-        let content = alloc::str::from_utf8(user_buffer.as_slice()).expect("Invalid content");        // TODO: print content
+        let content = alloc::str::from_utf8(user_buffer.as_slice()).expect("Invalid content"); // TODO: print content
         info!("Message from user mode: {:?}", content);
         SyscallResult::Return(0)
     } else {

src/kxos-user/hello_world/Makefile

@@ -1,9 +1,7 @@
 .PHONY: build clean run
 build: hello_world.s
-	@nasm -f elf64 hello_world.s -o hello_world.o
-	@ld hello_world.o -o hello_world
-	@rm hello_world.o
+	@gcc -static -nostdlib hello_world.s -o hello_world
 clean:
 	@rm hello_world
 run: build
-	@./hello_world
+	@./hello_world

src/kxos-user/hello_world/hello_world

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:0ac54a2485e87769b102225e0a2d7c25e449a01bd0b2504a164fe1ce205acb13
+size 9072

src/kxos-user/hello_world/hello_world.s

@@ -1,18 +1,24 @@
-global _start
-
-section .text
+.global _start
 
+.section .text
 _start:
-  mov rax, 1        ; syswrite
-  mov rdi, 1        ; fd
-  mov rsi, msg      ; "Hello, world!\n",
-  mov rdx, msglen   ; sizeof("Hello, world!\n")
-  syscall           
-
-  mov rax, 60       ; sys_exit
-  mov rdi, 0        ; exit_code
-  syscall           
-
-section .rodata
-  msg: db "Hello, world!", 10
-  msglen: equ $ - msg
+    call print_message
+    call print_message
+    call print_message
+    mov     $60, %rax               # syscall number of exit
+    mov     $0, %rdi                 # exit code
+    syscall     
+print_message:
+    mov     $1, %rax                # syscall number of write
+    mov     $1, %rdi                # stdout
+    mov     $message, %rsi          # address of message
+    mov     $message, %r11          
+    mov     $message_end, %r12
+    sub     %r11, %r12               # calculate message len
+    mov     %r12, %rdx               # number of bytes
+    syscall
+    ret
+.section .rodata            
+message:
+    .ascii  "Hello, world\n"
+message_end: