Switch Context::grants to RwLock

src/scheme/memory.rs

@@ -40,7 +40,7 @@ impl Scheme for MemoryScheme {
             let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
             let context = context_lock.read();
 
-            let mut grants = context.grants.lock();
+            let mut grants = context.grants.write();
 
             let region = grants.find_free_at(VirtualAddress::new(map.address), map.size, map.flags)?.round();
 

src/scheme/sys/context.rs

@@ -90,7 +90,7 @@ pub fn resource() -> Result<Vec<u8>> {
             if let Some(ref sigstack) = context.sigstack {
                 memory += sigstack.size();
             }
-            for grant in context.grants.lock().iter() {
+            for grant in context.grants.read().iter() {
                 if grant.is_owned() {
                     memory += grant.size();
                 }

src/scheme/user.rs

@@ -126,7 +126,7 @@ impl UserInner {
         let mut new_table = unsafe { InactivePageTable::from_address(context.arch.get_page_table()) };
         let mut temporary_page = TemporaryPage::new(Page::containing_address(VirtualAddress::new(crate::USER_TMP_GRANT_OFFSET)));
 
-        let mut grants = context.grants.lock();
+        let mut grants = context.grants.write();
 
         let from_address = round_down_pages(address);
         let offset = address - from_address;
@@ -157,7 +157,7 @@ impl UserInner {
             let mut new_table = unsafe { InactivePageTable::from_address(context.arch.get_page_table()) };
             let mut temporary_page = TemporaryPage::new(Page::containing_address(VirtualAddress::new(crate::USER_TMP_GRANT_OFFSET)));
 
-            let mut grants = context.grants.lock();
+            let mut grants = context.grants.write();
 
             if let Some(region) = grants.contains(VirtualAddress::new(address)).map(Region::from) {
                 grants.take(&region).unwrap().unmap_inactive(&mut new_table, &mut temporary_page);