Move flusher into a separate file

blockstore_flush.h

@@ -0,0 +1,51 @@
+struct copy_buffer_t
+{
+    uint64_t offset, len;
+    void *buf;
+};
+
+struct meta_sector_t
+{
+    uint64_t offset, len;
+    int state;
+    void *buf;
+    int usage_count;
+};
+
+class journal_flusher_t;
+
+// Journal flusher coroutine
+class journal_flusher_co
+{
+    blockstore *bs;
+    journal_flusher_t *flusher;
+    int wait_state, wait_count;
+    struct io_uring_sqe *sqe;
+    struct ring_data_t *data;
+    bool skip_copy;
+    obj_ver_id cur;
+    std::map<obj_ver_id, dirty_entry>::iterator dirty_it;
+    std::vector<copy_buffer_t> v;
+    std::vector<copy_buffer_t>::iterator it;
+    uint64_t offset, len, submit_len, clean_loc, meta_sector, meta_pos;
+    std::map<uint64_t, meta_sector_t>::iterator meta_it;
+    friend class journal_flusher_t;
+public:
+    void loop();
+};
+
+// Journal flusher itself
+class journal_flusher_t
+{
+    int flusher_count;
+    int active_flushers;
+    journal_flusher_co *co;
+    blockstore *bs;
+    friend class journal_flusher_co;
+public:
+    std::map<uint64_t, meta_sector_t> meta_sectors;
+    std::deque<obj_ver_id> flush_queue;
+    journal_flusher_t(int flusher_count, blockstore *bs);
+    ~journal_flusher_t();
+    void loop();
+};