From 6da3ab283e2145e77ee10786cc1efb471b9c750e Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jeremy@system76.com>
Date: Mon, 15 Apr 2019 20:47:03 -0600
Subject: [PATCH] Clone grants
---
src/syscall/process.rs | 32 +++++++++++++++++++++++++++++++-
1 file changed, 31 insertions(+), 1 deletion(-)
diff --git a/src/syscall/process.rs b/src/syscall/process.rs
index 37d93d70..e09df7fa 100644
--- a/src/syscall/process.rs
+++ b/src/syscall/process.rs
@@ -261,7 +261,12 @@ pub fn clone(flags: usize, stack_base: usize) -> Result<ContextId> {
if flags & CLONE_VM == CLONE_VM {
grants = Arc::clone(&context.grants);
} else {
- grants = Arc::new(Mutex::new(Vec::new()));
+ let mut grants_vec = Vec::new();
+ for grant in context.grants.lock().iter() {
+ let start = VirtualAddress::new(grant.start_address().get() + ::USER_TMP_GRANT_OFFSET - ::USER_GRANT_OFFSET);
+ grants_vec.push(grant.secret_clone(start));
+ }
+ grants = Arc::new(Mutex::new(grants_vec));
}
if flags & CLONE_VM == CLONE_VM {
@@ -306,6 +311,24 @@ pub fn clone(flags: usize, stack_base: usize) -> Result<ContextId> {
}
}
+ // If not cloning virtual memory, use fmap to re-obtain every grant where possible
+ if flags & CLONE_VM == 0 {
+ let mut i = 0;
+ while i < grants.lock().len() {
+ let mut remove = false;
+ if let Some(grant) = grants.lock().get(i) {
+ if let Some(ref _desc) = grant.desc_opt {
+ println!("todo: clone grant {} using fmap: {:?}", i, grant);
+ }
+ }
+ if remove {
+ grants.lock().remove(i);
+ } else {
+ i += 1;
+ }
+ }
+ }
+
// If vfork, block the current process
// This has to be done after the operations that may require context switches
if flags & CLONE_VFORK == CLONE_VFORK {
@@ -460,6 +483,13 @@ pub fn clone(flags: usize, stack_base: usize) -> Result<ContextId> {
});
context.heap = Some(heap_shared);
}
+
+ // Move grants
+ for grant in grants.lock().iter_mut() {
+ let start = VirtualAddress::new(grant.start_address().get() + ::USER_GRANT_OFFSET - ::USER_TMP_GRANT_OFFSET);
+ grant.move_to(start, &mut new_table, &mut temporary_page);
+ }
+ context.grants = grants;
}
// Setup user stack
--
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