Implement many process syscalls.

os/src/mm/page_table.rs

@@ -1,6 +1,15 @@
-use super::{frame_alloc, PhysPageNum, FrameTracker, VirtPageNum, VirtAddr, StepByOne};
+use super::{
+    frame_alloc,
+    PhysPageNum,
+    FrameTracker,
+    VirtPageNum,
+    VirtAddr,
+    PhysAddr,
+    StepByOne
+};
 use alloc::vec::Vec;
 use alloc::vec;
+use alloc::string::String;
 use bitflags::*;
 
 bitflags! {
@@ -126,6 +135,17 @@ impl PageTable {
         self.find_pte(vpn)
             .map(|pte| {pte.clone()})
     }
+    pub fn translate_va(&self, va: VirtAddr) -> Option<PhysAddr> {
+        self.find_pte(va.clone().floor())
+            .map(|pte| {
+                //println!("translate_va:va = {:?}", va);
+                let aligned_pa: PhysAddr = pte.ppn().into();
+                //println!("translate_va:pa_align = {:?}", aligned_pa);
+                let offset = va.page_offset();
+                let aligned_pa_usize: usize = aligned_pa.into();
+                (aligned_pa_usize + offset).into()
+            })
+    }
     pub fn token(&self) -> usize {
         8usize << 60 | self.root_ppn.0
     }
@@ -150,4 +170,28 @@ pub fn translated_byte_buffer(token: usize, ptr: *const u8, len: usize) -> Vec<&
         start = end_va.into();
     }
     v
+}
+
+pub fn translated_str(token: usize, ptr: *const u8) -> String {
+    let page_table = PageTable::from_token(token);
+    let mut string = String::new();
+    let mut va = ptr as usize;
+    loop {
+        let ch: u8 = *(page_table.translate_va(VirtAddr::from(va)).unwrap().get_mut());
+        if ch == 0 {
+            break;
+        } else {
+            string.push(ch as char);
+            va += 1;
+        }
+    }
+    string
+}
+
+pub fn translated_refmut<T>(token: usize, ptr: *mut T) -> &'static mut T {
+    //println!("into translated_refmut!");
+    let page_table = PageTable::from_token(token);
+    let va = ptr as usize;
+    //println!("translated_refmut: before translate_va");
+    page_table.translate_va(VirtAddr::from(va)).unwrap().get_mut()
 }