chk-ch8-part4

Author: wyfcyx

.gitignore

@@ -1,3 +1,4 @@
 os/target
 usr/rust/target
+os/src/link_user.S
 Cargo.lock

os/Cargo.toml

@@ -10,4 +10,4 @@ edition = "2018"
 riscv = { git = "https://github.com/rcore-os/riscv", features = ["inline-asm"] }
 spin = "0.5.2"
 buddy_system_allocator = "0.3"
-
+xmas-elf = "0.6"

os/Makefile

@@ -13,6 +13,8 @@ env:
 	rustup component add llvm-tools-preview rustfmt
 	rustup target add $(target)
 
+export USER_IMG = ../usr/rust/target/$(target)/debug/hello_world
+
 kernel:
 	cargo build
 

os/build.rs

@@ -0,0 +1,27 @@
+use std::fs::File;
+use std::io::{Result, Write};
+
+fn main() {
+    println!("cargo:rerun-if-env-changed=USER_IMG");
+    if let Ok(user_img) = std::env::var("USER_IMG") {
+        println!("cargo:rerun-if-changed={}", user_img);
+    }
+    gen_link_user_asm().unwrap();
+}
+
+/// Generate assembly file for linking user image
+fn gen_link_user_asm() -> Result<()> {
+    let mut f = File::create("src/link_user.S").unwrap();
+    let user_img = std::env::var("USER_IMG").unwrap();
+
+    writeln!(f, "# generated by build.rs - do not edit")?;
+    writeln!(f, r#"
+    .section .data
+    .global _user_img_start
+    .global _user_img_end
+_user_img_start:
+    .incbin "{}"
+_user_img_end:
+"#, user_img)?;
+    Ok(())
+}

os/src/consts.rs

@@ -13,3 +13,6 @@ pub const PHYSICAL_MEMORY_OFFSET: usize = 0xffffffff40000000;
 pub const PAGE_SIZE: usize = 4096;
 
 pub const KERNEL_STACK_SIZE: usize = 0x80000;
+
+pub const USER_STACK_SIZE: usize = 0x80000;
+pub const USER_STACK_OFFSET: usize = 0xffffffff00000000;

os/src/context.rs

@@ -46,7 +46,15 @@ impl Context {
         contextContent.tf.x[11] = args[1];
         contextContent.tf.x[12] = args[2];
     }
-
+	
+	pub unsafe fn new_user_thread(
+        entry: usize,
+        ustack_top: usize,
+        kstack_top: usize,
+        satp: usize
+    ) -> Self {
+        ContextContent::new_user_thread(entry, ustack_top, satp).push_at(kstack_top)
+    }
 }
 
 #[repr(C)]
@@ -86,6 +94,28 @@ impl ContextContent {
         content
     }
 
+	fn new_user_thread(
+        entry: usize,
+        ustack_top: usize,
+        satp: usize
+    ) -> Self {
+        ContextContent {
+            ra: __trapret as usize,
+            satp,
+            s: [0; 12],
+            tf: {
+                let mut tf: TrapFrame = unsafe { zeroed() };
+                tf.x[2] = ustack_top;
+                tf.sepc = entry;
+                tf.sstatus = sstatus::read();
+                tf.sstatus.set_spie(true);
+                tf.sstatus.set_sie(false);
+                tf.sstatus.set_spp(sstatus::SPP::User);
+                tf
+            }
+        }
+    }
+
 	unsafe fn push_at(self, stack_top: usize) -> Context {
         let ptr = (stack_top as *mut ContextContent).sub(1);
         *ptr = self;

os/src/init.rs

@@ -1,4 +1,5 @@
 global_asm!(include_str!("boot/entry64.asm"));
+global_asm!(include_str!("link_user.S"));
 
 use crate::consts::*;
 use crate::memory::{

os/src/interrupt.rs

@@ -40,6 +40,7 @@ pub fn rust_trap(tf: &mut TrapFrame) {
         Trap::Exception(Exception::InstructionPageFault) => page_fault(tf),
         Trap::Exception(Exception::LoadPageFault) => page_fault(tf),
         Trap::Exception(Exception::StorePageFault) => page_fault(tf),
+		Trap::Exception(Exception::UserEnvCall) => syscall(tf),
         _ => panic!("undefined trap!")
     }
 }
@@ -58,6 +59,16 @@ fn page_fault(tf: &mut TrapFrame) {
     panic!("page fault!");
 }
 
+fn syscall(tf: &mut TrapFrame) {
+    tf.sepc += 4;
+    let ret = crate::syscall::syscall(
+        tf.x[17],
+        [tf.x[10], tf.x[11], tf.x[12]],
+        tf
+    );
+    tf.x[10] = ret as usize;
+}
+
 #[inline(always)]
 pub fn disable_and_store() -> usize {
     let sstatus: usize;

os/src/lib.rs

@@ -18,3 +18,4 @@ mod timer;
 mod consts;
 mod memory;
 mod process;
+mod syscall;

os/src/memory/memory_set/area.rs

@@ -39,4 +39,19 @@ impl MemoryArea {
             attr : attr,
         }
     }
+
+	pub fn page_copy(&self, pt: &mut PageTableImpl, src: usize, length: usize) { 
+        let mut l = length;
+        let mut s = src;
+        for page in PageRange::new(self.start, self.end) {
+            self.handler.page_copy(
+                pt,
+                page,
+                s,
+                if l < PAGE_SIZE { l } else { PAGE_SIZE },
+            );
+            s += PAGE_SIZE;
+            if l >= PAGE_SIZE { l -= PAGE_SIZE; }
+        }
+    }
 }