uCore 32bit user program is runnable!

src/arch/x86_64/gdt.rs

@@ -35,6 +35,8 @@ pub fn init() {
         gdt.add_entry(UCODE);
         gdt.add_entry(KDATA);
         gdt.add_entry(UDATA);
+        gdt.add_entry(UCODE32);
+        gdt.add_entry(UDATA32);
         gdt.add_entry(Descriptor::tss_segment(&tss));
         gdt
     });
@@ -70,23 +72,29 @@ const KCODE: Descriptor = Descriptor::UserSegment(0x0020980000000000);  // EXECU
 const UCODE: Descriptor = Descriptor::UserSegment(0x0020F80000000000);  // EXECUTABLE | USER_SEGMENT | USER_MODE | PRESENT | LONG_MODE
 const KDATA: Descriptor = Descriptor::UserSegment(0x0000920000000000);  // DATA_WRITABLE | USER_SEGMENT | PRESENT
 const UDATA: Descriptor = Descriptor::UserSegment(0x0000F20000000000);  // DATA_WRITABLE | USER_SEGMENT | USER_MODE | PRESENT
+// Copied from xv6
+const UCODE32: Descriptor = Descriptor::UserSegment(0x00cffa00_0000ffff);
+// EXECUTABLE | USER_SEGMENT | USER_MODE | PRESENT
+const UDATA32: Descriptor = Descriptor::UserSegment(0x00cff200_0000ffff);  // EXECUTABLE | USER_SEGMENT | USER_MODE | PRESENT
 
 pub const KCODE_SELECTOR: SegmentSelector = SegmentSelector::new(1, PrivilegeLevel::Ring0);
 pub const UCODE_SELECTOR: SegmentSelector = SegmentSelector::new(2, PrivilegeLevel::Ring3);
 pub const KDATA_SELECTOR: SegmentSelector = SegmentSelector::new(3, PrivilegeLevel::Ring0);
 pub const UDATA_SELECTOR: SegmentSelector = SegmentSelector::new(4, PrivilegeLevel::Ring3);
-pub const TSS_SELECTOR: SegmentSelector = SegmentSelector::new(5, PrivilegeLevel::Ring0);
+pub const UCODE32_SELECTOR: SegmentSelector = SegmentSelector::new(5, PrivilegeLevel::Ring3);
+pub const UDATA32_SELECTOR: SegmentSelector = SegmentSelector::new(6, PrivilegeLevel::Ring3);
+pub const TSS_SELECTOR: SegmentSelector = SegmentSelector::new(7, PrivilegeLevel::Ring0);
 
 
 pub struct Gdt {
-    table: [u64; 8],
+    table: [u64; 10],
     next_free: usize,
 }
 
 impl Gdt {
     pub fn new() -> Gdt {
         Gdt {
-            table: [0; 8],
+            table: [0; 10],
             next_free: 1,
         }
     }

src/arch/x86_64/idt/mod.rs

@@ -25,6 +25,8 @@ pub fn init() {
             .set_flags(IdtFlags::PRESENT | IdtFlags::RING_3 | IdtFlags::INTERRUPT);
         idt[T_SYSCALL].set_handler_fn(syscall)
             .set_flags(IdtFlags::PRESENT | IdtFlags::RING_3 | IdtFlags::TRAP);
+        idt[0x80].set_handler_fn(syscall32)
+            .set_flags(IdtFlags::PRESENT | IdtFlags::RING_3 | IdtFlags::TRAP);
 
         unsafe {
             idt[T_DBLFLT].set_handler_fn(double_fault)

src/arch/x86_64/interrupt/handler.rs

@@ -18,7 +18,7 @@ interrupt_error_p!(double_fault, stack, {
 interrupt_error_p!(page_fault, stack, {
     use x86_64::registers::control_regs::cr2;
     let addr = cr2().0;
-    println!("\nEXCEPTION: Page Fault @ {:#x}", addr);
+    println!("\nEXCEPTION: Page Fault @ {:#x}, code: {:#x}", addr, stack.code);
 
     use memory::page_fault_handler;
     if page_fault_handler(addr) {
@@ -108,7 +108,15 @@ interrupt_stack_p!(to_kernel, stack, {
 });
 
 interrupt_stack_p!(syscall, stack, {
-    println!("\nInterupt: Syscall {}", stack.scratch.rax);
+    println!("\nInterupt: Syscall {:#x?}", stack.scratch.rax);
     use syscall::syscall;
-    syscall(stack);
+    let ret = syscall(stack, false);
+    stack.scratch.rax = ret as usize;
+});
+
+interrupt_stack_p!(syscall32, stack, {
+    println!("\nInterupt: Syscall {:#x?}", stack.scratch.rax);
+    use syscall::syscall;
+    let ret = syscall(stack, true);
+    stack.scratch.rax = ret as usize;
 });

src/arch/x86_64/interrupt/mod.rs

@@ -17,14 +17,14 @@ impl TrapFrame {
         tf.iret.rflags = 0x282;
         tf
     }
-    pub fn new_user_thread(entry_addr: usize, rsp: usize) -> Self {
+    pub fn new_user_thread(entry_addr: usize, rsp: usize, is32: bool) -> Self {
         use arch::gdt;
         let mut tf = TrapFrame::default();
-        tf.iret.cs = gdt::UCODE_SELECTOR.0 as usize;
+        tf.iret.cs = if is32 { gdt::UCODE32_SELECTOR.0 } else { gdt::UCODE_SELECTOR.0 } as usize;
         tf.iret.rip = entry_addr;
-        tf.iret.ss = gdt::UDATA_SELECTOR.0 as usize;
+        tf.iret.ss = if is32 { gdt::UDATA32_SELECTOR.0 } else { gdt::UDATA_SELECTOR.0 } as usize;
         tf.iret.rsp = rsp;
-        tf.iret.rflags = 0x3282;
+        tf.iret.rflags = 0x282;
         tf
     }
 }

src/arch/x86_64/interrupt/template.rs

@@ -339,7 +339,7 @@ macro_rules! interrupt_switch {
             use arch::gdt;
             use core::mem::size_of;
             let tf = &mut *(rsp as *mut TrapFrame);
-            if tf.iret.cs == gdt::UCODE_SELECTOR.0 as usize {
+            if tf.iret.cs & 0x3 == 3 {
                 gdt::set_ring0_rsp(rsp + size_of::<TrapFrame>());
             }
 

src/process/mod.rs

@@ -34,6 +34,8 @@ use arch::interrupt::TrapFrame;
 extern {
     fn _binary_user_forktest_start();
     fn _binary_user_forktest_end();
+    fn _binary_hello_start();
+    fn _binary_hello_end();
 }
 
 
@@ -42,12 +44,14 @@ pub fn init(mut mc: MemoryController) {
         let initproc = Process::new_init(&mut mc);
         let idleproc = Process::new("idle", idle_thread, &mut mc);
         #[cfg(feature = "link_user_program")]
-        let forktest = Process::new_user(_binary_user_forktest_start as usize,
-                                         _binary_user_forktest_end as usize, &mut mc);
+//        let forktest = Process::new_user(_binary_user_forktest_start as usize,
+//                                         _binary_user_forktest_end as usize, &mut mc);
+        let hello = Process::new_user(_binary_hello_start as usize,
+                                      _binary_hello_end as usize, &mut mc);
         let mut processor = Processor::new(mc);
         processor.add(initproc);
         processor.add(idleproc);
-        processor.add(forktest);
+        processor.add(hello);
         processor
     })});
 }

src/process/process.rs

@@ -61,39 +61,60 @@ impl Process {
 
     /// Make a new user thread
     /// The program elf data is placed at [begin, end)
+    /// uCore x86 32bit program is planned to be supported.
     pub fn new_user(begin: usize, end: usize, mc: &mut MemoryController) -> Self {
         // Parse elf
         let slice = unsafe{ slice::from_raw_parts(begin as *const u8, end - begin) };
         let elf = ElfFile::new(slice).expect("failed to read elf");
+        let is32 = match elf.header.pt2 {
+            HeaderPt2::Header32(_) => true,
+            HeaderPt2::Header64(_) => false,
+        };
+
+        // User stack
+        use consts::{USER_STACK_OFFSET, USER_STACK_SIZE, USER_TCB_OFFSET};
+        let (user_stack_buttom, mut user_stack_top) = match is32 {
+            true => (USER_TCB_OFFSET, USER_TCB_OFFSET + USER_STACK_SIZE),
+            false => (USER_STACK_OFFSET, USER_STACK_OFFSET + USER_STACK_SIZE),
+        };
 
         // Make page table
-        use consts::{USER_STACK_OFFSET, USER_STACK_SIZE};
         let mut memory_set = MemorySet::from(&elf);
-        memory_set.push(MemoryArea::new(USER_STACK_OFFSET, USER_STACK_OFFSET + USER_STACK_SIZE,
+        memory_set.push(MemoryArea::new(user_stack_buttom, user_stack_top,
                                         EntryFlags::WRITABLE | EntryFlags::NO_EXECUTE | EntryFlags::USER_ACCESSIBLE, "user_stack"));
         let page_table = mc.make_page_table(&memory_set);
         debug!("{:#x?}", memory_set);
 
+        let entry_addr = match elf.header.pt2 {
+            HeaderPt2::Header32(header) => header.entry_point as usize,
+            HeaderPt2::Header64(header) => header.entry_point as usize,
+        };
+
         // Temporary switch to it, in order to copy data
         let page_table = mc.with(page_table, || {
             for ph in elf.program_iter() {
-                let ph = match ph {
-                    ProgramHeader::Ph64(ph) => ph,
-                    _ => unimplemented!(),
+                let (virt_addr, offset, file_size) = match ph {
+                    ProgramHeader::Ph32(ph) => (ph.virtual_addr as usize, ph.offset as usize, ph.file_size as usize),
+                    ProgramHeader::Ph64(ph) => (ph.virtual_addr as usize, ph.offset as usize, ph.file_size as usize),
                 };
-                unsafe { memcpy(ph.virtual_addr as *mut u8, (begin + ph.offset as usize) as *mut u8, ph.file_size as usize) };
+                unsafe { memcpy(virt_addr as *mut u8, (begin + offset) as *mut u8, file_size) };
+            }
+            if is32 {
+                unsafe {
+                    // TODO: full argc & argv
+                    *(user_stack_top as *mut u32).offset(-1) = 0; // argv
+                    *(user_stack_top as *mut u32).offset(-2) = 0; // argc
+                    user_stack_top -= 8;
+                }
             }
         });
 
-        let entry_addr = match elf.header.pt2 {
-            HeaderPt2::Header64(header) => header.entry_point,
-            _ => unimplemented!(),
-        } as usize;
 
         // Allocate kernel stack and push trap frame
         let kstack = mc.alloc_stack(7).unwrap();
-        let tf = TrapFrame::new_user_thread(entry_addr, USER_STACK_OFFSET + USER_STACK_SIZE);
+        let tf = TrapFrame::new_user_thread(entry_addr, user_stack_top, is32);
         let rsp = kstack.push_at_top(tf);
+        debug!("rsp = {:#x}", rsp);
 
         Process {
             pid: 0,
@@ -153,15 +174,11 @@ impl<'a> From<&'a ElfFile<'a>> for MemorySet {
     fn from(elf: &'a ElfFile<'a>) -> Self {
         let mut set = MemorySet::new();
         for ph in elf.program_iter() {
-            let ph = match ph {
-                ProgramHeader::Ph64(ph) => ph,
-                _ => unimplemented!(),
+            let (virt_addr, mem_size, flags) = match ph {
+                ProgramHeader::Ph32(ph) => (ph.virtual_addr as usize, ph.mem_size as usize, ph.flags),
+                ProgramHeader::Ph64(ph) => (ph.virtual_addr as usize, ph.mem_size as usize, ph.flags),
             };
-            set.push(MemoryArea::new(
-                ph.virtual_addr as usize,
-                (ph.virtual_addr + ph.mem_size) as usize,
-                EntryFlags::from(ph.flags),
-                ""));
+            set.push(MemoryArea::new(virt_addr, virt_addr + mem_size, EntryFlags::from(flags), ""));
         }
         set
     }
@@ -170,7 +187,9 @@ impl<'a> From<&'a ElfFile<'a>> for MemorySet {
 impl From<Flags> for EntryFlags {
     fn from(elf_flags: Flags) -> Self {
         let mut flags = EntryFlags::PRESENT | EntryFlags::USER_ACCESSIBLE;
-        if elf_flags.is_write() {
+//        if elf_flags.is_write() {
+        // TODO: handle readonly
+        if true {
             flags = flags | EntryFlags::WRITABLE;
         }
         if !elf_flags.is_execute() {

src/syscall.rs

@@ -2,12 +2,24 @@ use super::*;
 use process;
 use arch::interrupt::TrapFrame;
 
-pub unsafe fn syscall(tf: &TrapFrame) -> i32 {
-    let id = tf.scratch.rax;
-    // For ucore:
-//    let args = [tf.scratch.rdx, tf.scratch.rcx, tf.preserved.rbx, tf.scratch.rdi, tf.scratch.rsi];
-    // For xv6 x86_64
-    let args = [tf.scratch.rdi, tf.scratch.rsi, tf.scratch.rdx, tf.scratch.rcx, tf.scratch.r8, tf.scratch.r9];
+pub unsafe fn syscall(tf: &TrapFrame, is32: bool) -> i32 {
+    let id = match is32 {
+        false => tf.scratch.rax,
+        true => match tf.scratch.rax {
+            UCORE_SYS_OPEN => SYS_OPEN,
+            UCORE_SYS_CLOSE => SYS_CLOSE,
+            UCORE_SYS_WRITE => SYS_WRITE,
+            UCORE_SYS_READ => SYS_READ,
+            _ => 0,
+        }
+    };
+    let args = match is32 {
+        // For ucore x86
+        true => [tf.scratch.rdx, tf.scratch.rcx, tf.preserved.rbx, tf.scratch.rdi, tf.scratch.rsi, 0],
+        // For xv6 x86_64
+        false => [tf.scratch.rdi, tf.scratch.rsi, tf.scratch.rdx, tf.scratch.rcx, tf.scratch.r8, tf.scratch.r9],
+    };
+    debug!("id: {:#x}, args: {:#x?}", id, args);
 
     match id {
         SYS_FORK => {
@@ -19,7 +31,7 @@ pub unsafe fn syscall(tf: &TrapFrame) -> i32 {
             0
         }
         _ => {
-            debug!("unknown syscall {}", id);
+            debug!("unknown syscall {:#x}", id);
             -1
         }
     }
@@ -47,3 +59,29 @@ const SYS_LINK: usize = 19;
 const SYS_MKDIR: usize = 20;
 const SYS_CLOSE: usize = 21;
 const SYS_CHMOD: usize = 22;
+
+const UCORE_SYS_EXIT: usize = 1;
+const UCORE_SYS_FORK: usize = 2;
+const UCORE_SYS_WAIT: usize = 3;
+const UCORE_SYS_EXEC: usize = 4;
+const UCORE_SYS_CLONE: usize = 5;
+const UCORE_SYS_YIELD: usize = 10;
+const UCORE_SYS_SLEEP: usize = 11;
+const UCORE_SYS_KILL: usize = 12;
+const UCORE_SYS_GETTIME: usize = 17;
+const UCORE_SYS_GETPID: usize = 18;
+const UCORE_SYS_MMAP: usize = 20;
+const UCORE_SYS_MUNMAP: usize = 21;
+const UCORE_SYS_SHMEM: usize = 22;
+const UCORE_SYS_PUTC: usize = 30;
+const UCORE_SYS_PGDIR: usize = 31;
+const UCORE_SYS_OPEN: usize = 100;
+const UCORE_SYS_CLOSE: usize = 101;
+const UCORE_SYS_READ: usize = 102;
+const UCORE_SYS_WRITE: usize = 103;
+const UCORE_SYS_SEEK: usize = 104;
+const UCORE_SYS_FSTAT: usize = 110;
+const UCORE_SYS_FSYNC: usize = 111;
+const UCORE_SYS_GETCWD: usize = 121;
+const UCORE_SYS_GETDIRENTRY: usize = 128;
+const UCORE_SYS_DUP: usize = 130;