From 754a245d597c122f56ff0e39b50d778d2de58eab Mon Sep 17 00:00:00 2001
From: Avi Kivity <avi@cloudius-systems.com>
Date: Sun, 24 Aug 2014 11:04:59 +0300
Subject: [PATCH] Implement file::flush()

---
 reactor.cc | 9 +++++++++
 reactor.hh | 5 ++++-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/reactor.cc b/reactor.cc
index fcca98f1b7..676b70d481 100644
--- a/reactor.cc
+++ b/reactor.cc
@@ -189,6 +189,15 @@ reactor::open_file_dma(sstring name) {
     });
 }
 
+future<>
+reactor::flush(file& f) {
+    return _thread_pool.submit<syscall_result<int>>([&f] {
+        return wrap_syscall<int>(::fsync(f._fd));
+    }).then([] (syscall_result<int> sr) {
+        assert(sr.result != -1);
+        return make_ready_future<>();
+    });
+}
 
 void reactor::run() {
     std::vector<std::unique_ptr<task>> current_tasks;
diff --git a/reactor.hh b/reactor.hh
index 2bd3fecb3e..6e4a6a9222 100644
--- a/reactor.hh
+++ b/reactor.hh
@@ -423,6 +423,7 @@ public:
     future<size_t> write_all(pollable_fd_state& fd, const void* buffer, size_t size);
 
     future<file> open_file_dma(sstring name);
+    future<> flush(file& f);
 
     void run();
 
@@ -603,7 +604,9 @@ public:
         return the_reactor.write_dma(*this, pos, std::move(iov));
     }
 
-    future<> flush();
+    future<> flush() {
+        return the_reactor.flush(*this);
+    }
 
     friend class reactor;
 };