From 78e94fe29b0af964f92d012f59e277a796223041 Mon Sep 17 00:00:00 2001
From: "Tate, Hongliang Tian" <tatetian@gmail.com>
Date: Wed, 9 Jan 2019 22:50:39 +0800
Subject: [PATCH] Add sync syscall

---
 src/Enclave.edl                       |  1 +
 src/libos/include/syscall.h           |  2 ++
 src/libos/src/fs/mod.rs               |  9 +++++++++
 src/libos/src/syscall/mod.rs          | 13 +++++++++++++
 src/libos/src/syscall/syscall_entry.c |  4 ++++
 src/pal/pal.c                         |  4 ++++
 6 files changed, 33 insertions(+)

diff --git a/src/Enclave.edl b/src/Enclave.edl
index e3a2014e..71bbdd60 100644
--- a/src/Enclave.edl
+++ b/src/Enclave.edl
@@ -15,5 +15,6 @@ enclave {
         void ocall_print_string([in, string] const char* msg);
         int ocall_run_new_task(void);
         void ocall_gettimeofday([out] long* seconds, [out] long* microseconds);
+        void ocall_sync(void);
     };
 };
diff --git a/src/libos/include/syscall.h b/src/libos/include/syscall.h
index 9d76aad4..756807f7 100644
--- a/src/libos/include/syscall.h
+++ b/src/libos/include/syscall.h
@@ -19,6 +19,8 @@ extern ssize_t occlum_write(int fd, const void* buf, size_t size);
 extern ssize_t occlum_writev(int fd, const struct iovec* iov, int count);
 extern off_t occlum_lseek(int fd, off_t offset, int whence);
 
+extern int occlum_sync(void);
+
 extern int occlum_pipe(int fds[2]);
 extern int occlum_pipe2(int fds[2], int flags);
 
diff --git a/src/libos/src/fs/mod.rs b/src/libos/src/fs/mod.rs
index 48871f6a..018baf9d 100644
--- a/src/libos/src/fs/mod.rs
+++ b/src/libos/src/fs/mod.rs
@@ -153,3 +153,12 @@ pub fn do_dup3(old_fd: FileDesc, new_fd: FileDesc, flags: u32) -> Result<FileDes
     file_table.put_at(new_fd, file, close_on_spawn);
     Ok(new_fd)
 }
+
+pub fn do_sync() -> Result<(), Error> {
+    unsafe { ocall_sync(); }
+    Ok(())
+}
+
+extern {
+    fn ocall_sync() -> sgx_status_t;
+}
diff --git a/src/libos/src/syscall/mod.rs b/src/libos/src/syscall/mod.rs
index e9cce890..8335ef89 100644
--- a/src/libos/src/syscall/mod.rs
+++ b/src/libos/src/syscall/mod.rs
@@ -540,6 +540,19 @@ pub extern "C" fn occlum_dup3(old_fd: c_int, new_fd: c_int, flags: c_int)
     }
 }
 
+#[no_mangle]
+pub extern "C" fn occlum_sync() -> c_int
+{
+    match fs::do_sync() {
+        Ok(()) => {
+            0 as c_int
+        }
+        Err(e) => {
+            e.errno.as_retval()
+        }
+    }
+}
+
 // TODO: handle tz: timezone_t
 #[no_mangle]
 pub extern "C" fn occlum_gettimeofday(tv: *mut timeval_t) -> c_int
diff --git a/src/libos/src/syscall/syscall_entry.c b/src/libos/src/syscall/syscall_entry.c
index 75be0c7c..ba4579f9 100644
--- a/src/libos/src/syscall/syscall_entry.c
+++ b/src/libos/src/syscall/syscall_entry.c
@@ -85,6 +85,10 @@ long dispatch_syscall(int num, long arg0, long arg1, long arg2, long arg3, long
         ret = occlum_getppid();
         break;
     }
+    case SYS_sync: {
+        ret = occlum_sync();
+        break;
+    }
     case SYS_mmap: {
         DECL_SYSCALL_ARG(void*, addr, arg0);
         DECL_SYSCALL_ARG(size_t, length, arg1);
diff --git a/src/pal/pal.c b/src/pal/pal.c
index c8399074..91d3cf31 100644
--- a/src/pal/pal.c
+++ b/src/pal/pal.c
@@ -205,6 +205,10 @@ void ocall_gettimeofday(long* seconds, long* microseconds) {
     *microseconds = tv.tv_usec;
 }
 
+void ocall_sync(void) {
+    sync();
+}
+
 
 /* Application entry */
 int SGX_CDECL main(int argc, const char *argv[])