finish frame delayed allocating

crate/memory/src/cow.rs

@@ -91,6 +91,28 @@ impl<T: PageTable> CowExt<T> {
     **  @retval bool                 whether copy-on-write happens.
     */
     pub fn page_fault_handler(&mut self, addr: VirtAddr, alloc_frame: impl FnOnce() -> PhysAddr) -> bool {
+        // handle page delayed allocating
+        {
+            info!("try handling delayed frame allocator");
+            let need_alloc ={
+                let entry = self.page_table.get_entry(addr);
+                //info!("got entry!");
+                !entry.present() && !entry.swapped()
+            };
+            if need_alloc{
+                info!("need_alloc!");
+                let frame = alloc_frame();
+                let entry = self.page_table.get_entry(addr);
+                entry.set_target(frame);
+                //let new_entry = self.page_table.map(addr, frame);
+                entry.set_present(true);
+                entry.update();
+                //area.get_flags().apply(new_entry); this instruction may be used when hide attr is used
+                info!("allocated successfully");
+                return true;
+            }
+        }
+        // below is not being used now(no shared pages)
         {
             let entry = self.page_table.get_entry(addr);
             if !entry.readonly_shared() && !entry.writable_shared() {

crate/memory/src/memory_set.rs

@@ -173,11 +173,22 @@ impl MemoryArea {
                 }
             }
             None => {
+                info!("map delayed!");
                 for page in Page::range_of(self.start_addr, self.end_addr) {
                     let addr = page.start_address();
-                    let target = T::alloc_frame().expect("failed to allocate frame");
+                    //let target = T::alloc_frame().expect("failed to allocate frame");
-                    self.flags.apply(pt.map(addr, target));
+                    //self.flags.apply(pt.map(addr, target));
+                    // for frame delayed allocation
+                    {
+                        let entry = pt.map(addr,0);
+                        self.flags.apply(entry);
+                    }
+                    let entry = pt.get_entry(addr);
+                    entry.set_present(false);
+                    entry.update();
+
                 }
+                info!("finish map delayed!");
             }
         }
     }
@@ -190,8 +201,14 @@ impl MemoryArea {
         for page in Page::range_of(self.start_addr, self.end_addr) {
             let addr = page.start_address();
             if self.phys_start_addr.is_none() {
-                let target = pt.get_entry(addr).target();
+                if pt.get_entry(addr).present(){
-                T::dealloc_frame(target);
+                    let target = pt.get_entry(addr).target();
+                    T::dealloc_frame(target);
+                }
+                else{
+                    // set valid for pt.unmap function
+                    pt.get_entry(addr).set_present(true);
+                }
             }
             pt.unmap(addr);
         }
@@ -204,6 +221,11 @@ impl MemoryArea {
     pub fn get_end_addr(&self) -> VirtAddr{
         self.end_addr
     }
+
+    pub fn get_flags(&self) -> &MemoryAttr{
+        &self.flags
+    }
+
 }
 
 /// The attributes of the memory
@@ -377,6 +399,7 @@ impl<T: InactivePageTable> MemorySet<T> {
     pub fn get_page_table_mut(&mut self) -> &mut T{
         &mut self.page_table
     }
+
 }
 
 impl<T: InactivePageTable> Clone for MemorySet<T> {

crate/memory/src/swap/mod.rs

@@ -147,6 +147,7 @@ impl<T: PageTable, M: SwapManager, S: Swapper> SwapExt<T, M, S> {
                 entry.update();
                 token
             };
+            info!("swap in vaddr {:x?} at remove from swappable.", addr);
             let data = page_table.get_page_slice_mut(addr);
             swapper.swap_in(token, data).unwrap();
         });
@@ -172,6 +173,7 @@ impl<T: PageTable, M: SwapManager, S: Swapper> SwapExt<T, M, S> {
     **                               the error if failed
     */
     pub fn swap_out_any<T2: InactivePageTable>(&mut self) -> Result<PhysAddr, SwapError> {
+        info!("COME in to swap_out_any");
         let victim: Option<Frame> = {
             let Self {ref mut page_table, ref mut swap_manager, ref mut swapper} = self;
             swap_manager.pop(page_table, swapper)

kernel/src/memory.rs

@@ -7,8 +7,9 @@ use ucore_memory::{*, paging::PageTable};
 use ucore_memory::cow::CowExt;
 pub use ucore_memory::memory_set::{MemoryArea, MemoryAttr, MemorySet as MemorySet_, Stack};
 use ucore_memory::swap::*;
-use process::processor;
+use process::{processor, PROCESSOR};
 use sync::{SpinNoIrqLock, SpinNoIrq, MutexGuard};
+use ucore_memory::paging::Entry;
 
 pub type MemorySet = MemorySet_<InactivePageTable0>;
 
@@ -85,16 +86,48 @@ pub fn alloc_stack() -> Stack {
 *   Return true to continue, false to halt  
 */
 pub fn page_fault_handler(addr: usize) -> bool {
-    // Handle copy on write (not being used now)
+    // since some page fault for frame delayed allocating may occur in the building of the process, we can't use processor() to get the real memset for it
+    // unless we write a mmset manager for all the memory set, which is a little bit hard.
+    /*
+    info!("come in to page fault handler.");
+    {
+        info!("1");
+        unsafe{ PROCESSOR.try().unwrap().force_unlock();}
+        let mut temp_proc = processor();
+        info!("2");
+        let mmset = temp_proc.current_context_mut().get_memory_set_mut();
+        let target_area = mmset.find_area(addr);
+        // check whether the virtual address is valid
+        info!("checked the valid virtual address");
+        match target_area {
+            None => {
+                info!("invalid virtual address: {:x?}", addr);
+                return false;
+            },
+            Some(area)=>{
+                // Handle delayed frame allocate and copy on write (the second not being used now)
+                unsafe { ACTIVE_TABLE.force_unlock(); }
+                if active_table().page_fault_handler(addr, || alloc_frame().unwrap()) {
+                    return true;
+                }
+            },
+        }
+    }
+    */
+
+    // Handle delayed frame allocate and copy on write (the second not being used now)
     unsafe { ACTIVE_TABLE.force_unlock(); }
     if active_table().page_fault_handler(addr, || alloc_frame().unwrap()){
+        info!("general page fault handle successfully!");
         return true;
     }
+
+
     // handle the swap in/out
     info!("start handling swap in/out page fault");
-    unsafe { ACTIVE_TABLE_SWAP.force_unlock(); }
     let mut temp_proc = processor();
     let pt = temp_proc.current_context_mut().get_memory_set_mut().get_page_table_mut();
+    unsafe { ACTIVE_TABLE_SWAP.force_unlock(); }
     if active_table_swap().page_fault_handler(pt as *mut InactivePageTable0, addr, || alloc_frame().unwrap()){
         return true;
     }

kernel/src/process/context.rs

@@ -61,6 +61,7 @@ impl Context {
     *   the new user thread Context
     */
     pub fn new_user(data: &[u8]) -> Self {
+        info!("come into new user");
         // Parse elf
         let elf = ElfFile::new(data).expect("failed to read elf");
         let is32 = match elf.header.pt2 {
@@ -70,6 +71,7 @@ impl Context {
         assert_eq!(elf.header.pt2.type_().as_type(), header::Type::Executable, "ELF is not executable");
 
         // User stack
+        info!("start building suer stack");
         use consts::{USER_STACK_OFFSET, USER_STACK_SIZE, USER32_STACK_OFFSET};
         let (user_stack_buttom, user_stack_top) = match is32 {
             true => (USER32_STACK_OFFSET, USER32_STACK_OFFSET + USER_STACK_SIZE),
@@ -77,13 +79,16 @@ impl Context {
         };
 
         // Make page table
+        info!("make page table!");
         let mut memory_set = memory_set_from(&elf);
+        info!("start to push user stack to the mmset");
         memory_set.push(MemoryArea::new(user_stack_buttom, user_stack_top, MemoryAttr::default().user(), "user_stack"));
         trace!("{:#x?}", memory_set);
 
         let entry_addr = elf.header.pt2.entry_point() as usize;
 
         // Temporary switch to it, in order to copy data
+        info!("starting copy data.");
         unsafe {
             memory_set.with(|| {
                 for ph in elf.program_iter() {
@@ -93,9 +98,13 @@ impl Context {
                     if file_size == 0 {
                         return;
                     }
+                    info!("file virtaddr: {:x?}, file size: {:x?}", virt_addr, file_size);
                     use core::slice;
+                    info!("starting copy!");
                     let target = unsafe { slice::from_raw_parts_mut(virt_addr as *mut u8, file_size) };
+                    info!("target got!");
                     target.copy_from_slice(&data[offset..offset + file_size]);
+                    info!("finish copy!");
                 }
                 if is32 {
                     unsafe {
@@ -106,10 +115,10 @@ impl Context {
                 }
             });
         }
-
+        info!("ending copy data.");
         
         //set the user Memory pages in the memory set swappable
-        memory_set_map_swappable(&mut memory_set);
+        //memory_set_map_swappable(&mut memory_set);
 
         Context {
             arch: unsafe {
@@ -156,6 +165,7 @@ impl Context {
 
 impl Drop for Context{
     fn drop(&mut self){
+        /*
         //set the user Memory pages in the memory set unswappable
         let Self {ref mut arch, ref mut memory_set} = self;
         let pt = {
@@ -170,7 +180,7 @@ impl Drop for Context{
             }
         }
         info!("Finishing setting pages unswappable");
-        
+        */
     }
 }
 
@@ -189,6 +199,7 @@ impl Debug for Context {
 *   the new memory set
 */
 fn memory_set_from<'a>(elf: &'a ElfFile<'a>) -> MemorySet {
+    info!("come in to memory_set_from");
     let mut set = MemorySet::new();
     for ph in elf.program_iter() {
         if ph.get_type() != Ok(Type::Load) {
@@ -198,6 +209,7 @@ fn memory_set_from<'a>(elf: &'a ElfFile<'a>) -> MemorySet {
             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),//???
         };
+        info!("push!");
         set.push(MemoryArea::new(virt_addr, virt_addr + mem_size, memory_attr_from(flags), ""));
 
     }

kernel/src/trap.rs

@@ -12,8 +12,12 @@ pub fn timer() {
 
 pub fn before_return() {
     if let Some(processor) = PROCESSOR.try() {
-        processor.lock().schedule();
+        // try lock for delayed frame allocated to avoid deadlock
+        if processor.try_lock().is_some() {
+            processor.lock().schedule();
+        }
     }
+    //info!("finish before return!");
 }
 
 /*