fix bugs in mremap and 9p's rename

api/ruxos_posix_api/src/imp/mmap/api.rs

@@ -46,14 +46,6 @@ pub fn sys_mmap(
     syscall_body!(sys_mmap, {
         // transform C-type into rust-type
         let start = start as usize;
-        let len = VirtAddr::from(len).align_up_4k().as_usize();
-        if !VirtAddr::from(start).is_aligned(PAGE_SIZE_4K) || len == 0 {
-            error!(
-                "mmap failed because start:0x{:x} is not aligned or len:0x{:x} == 0",
-                start, len
-            );
-            return Err(LinuxError::EINVAL);
-        }
         let prot = prot as u32;
         let flags = flags as u32;
         let fid = fd;
@@ -75,6 +67,22 @@ pub fn sys_mmap(
             fid
         };
 
+        // align len to PAGE_SIZE_4K depending on `MAP_ANONYMOUS` or not.
+        let len = if fid < 0 {
+            VirtAddr::from(len).align_up_4k().as_usize()
+        } else {
+            VirtAddr::from(len).as_usize()
+        };
+
+        // check if `start` is aligned to `PAGE_SIZE_4K`or len is large than 0.
+        if !VirtAddr::from(start).is_aligned(PAGE_SIZE_4K) || len == 0 {
+            error!(
+                "mmap failed because start:0x{:x} is not aligned or len:0x{:x} == 0",
+                start, len
+            );
+            return Err(LinuxError::EINVAL);
+        }
+
         let mut new = Vma::new(fid, offset, prot, flags);
         let mut vma_map = VMA_MAP.lock();
         let addr_condition = if start == 0 { None } else { Some(start) };
@@ -103,7 +111,7 @@ pub fn sys_munmap(start: *mut c_void, len: ctypes::size_t) -> c_int {
     syscall_body!(sys_munmap, {
         // transform C-type into rust-type
         let start = start as usize;
-        let end = VirtAddr::from(start + len).align_up_4k().as_usize();
+        let end = VirtAddr::from(start + len).as_usize();
 
         if !VirtAddr::from(start).is_aligned(PAGE_SIZE_4K) || len == 0 {
             error!(
@@ -171,7 +179,7 @@ pub fn sys_munmap(start: *mut c_void, len: ctypes::size_t) -> c_int {
         }
 
         // delete the mapped and swapped page.
-        release_pages_mapped(start, end);
+        release_pages_mapped(start, end, true);
         #[cfg(feature = "fs")]
         release_pages_swaped(start, end);
 
@@ -191,7 +199,7 @@ pub fn sys_mprotect(start: *mut c_void, len: ctypes::size_t, prot: c_int) -> c_i
     syscall_body!(sys_mprotect, {
         // transform C-type into rust-type
         let start = start as usize;
-        let end = VirtAddr::from(start + len).align_up_4k().as_usize();
+        let end = VirtAddr::from(start + len).as_usize();
         if !VirtAddr::from(start).is_aligned(PAGE_SIZE_4K) || len == 0 {
             return Err(LinuxError::EINVAL);
         }
@@ -293,7 +301,7 @@ pub fn sys_msync(start: *mut c_void, len: ctypes::size_t, flags: c_int) -> c_int
         #[cfg(feature = "fs")]
         {
             let start = start as usize;
-            let end = VirtAddr::from(start + len).align_up_4k().as_usize();
+            let end = VirtAddr::from(start + len).as_usize();
             if !VirtAddr::from(start).is_aligned(PAGE_SIZE_4K) || len == 0 {
                 return Err(LinuxError::EINVAL);
             }
@@ -444,7 +452,7 @@ pub fn sys_mremap(
             old_vma.end_addr = new_end;
 
             // delete the mapped and swapped page outside of new vma.
-            release_pages_mapped(new_end, old_end);
+            release_pages_mapped(new_end, old_end, false);
             #[cfg(feature = "fs")]
             release_pages_swaped(new_end, old_end);
 

api/ruxos_posix_api/src/imp/mmap/utils.rs

@@ -28,8 +28,8 @@ use ruxhal::{
 // use `used_fs` instead of `#[cfg(feature = "fs")]{}` to cancel the scope of code.
 #[cfg(feature = "fs")]
 macro_rules! used_fs {
-    ($($code:tt)*) => {$($code)*};
-}
+      ($($code:tt)*) => {$($code)*};
+  }
 
 #[cfg(not(feature = "fs"))]
 macro_rules! used_fs {
@@ -204,9 +204,11 @@ pub(crate) fn find_free_region(
     }
 
     // Search free region on the top of VMA_LISTS first.
+    const ALIGN_PAGE_MASK: usize = !(PAGE_SIZE_4K - 1);
     if let Some((_, last_vma)) = vma_map.last_key_value() {
-        if VMA_END - last_vma.end_addr >= len {
-            return Some(last_vma.end_addr);
+        let end_boundry = (last_vma.end_addr + PAGE_SIZE_4K) & ALIGN_PAGE_MASK;
+        if (VMA_END - end_boundry) & ALIGN_PAGE_MASK >= len {
+            return Some(end_boundry);
         }
     } else if VMA_END >= VMA_START + len {
         return Some(VMA_START);
@@ -274,7 +276,7 @@ pub(crate) fn snatch_fixed_region(
     }
 
     // delete the mapped and swapped page.
-    release_pages_mapped(start, end);
+    release_pages_mapped(start, end, true);
     #[cfg(feature = "fs")]
     release_pages_swaped(start, end);
 
@@ -283,14 +285,16 @@ pub(crate) fn snatch_fixed_region(
 
 /// release the range of [start, end) in mem_map
 /// take care of AA-deadlock, this function should not be used after `MEM_MAP` is used.
-pub(crate) fn release_pages_mapped(start: usize, end: usize) {
+pub(crate) fn release_pages_mapped(start: usize, end: usize, writeback: bool) {
     let mut memory_map = MEM_MAP.lock();
     let mut removing_vaddr = Vec::new();
     for (&vaddr, _page_info) in memory_map.range(start..end) {
         #[cfg(feature = "fs")]
-        if let Some((file, offset, size)) = _page_info {
-            let src = vaddr as *mut u8;
-            write_into(file, src, *offset as u64, *size);
+        if writeback {
+            if let Some((file, offset, size)) = _page_info {
+                let src = vaddr as *mut u8;
+                write_into(file, src, *offset as u64, *size);
+            }
         }
         if pte_unmap_page(VirtAddr::from(vaddr)).is_err() {
             panic!("Release page failed when munmapping!");

modules/rux9p/src/fs.rs

@@ -351,7 +351,7 @@ impl VfsNodeOps for CommonNode {
             ("", src_path)
         };
 
-        let (dst_prefixs, new_name) = if let Some(dst_sindex) = src_path.rfind('/') {
+        let (dst_prefixs, new_name) = if let Some(dst_sindex) = dst_path.rfind('/') {
             (&dst_path[..dst_sindex], &dst_path[dst_sindex + 1..])
         } else {
             ("", dst_path)