[cache_writeback] Coded, needs testing

block-cache/copier.h

@@ -1,27 +1,75 @@
 #ifndef BLOCK_CACHE_COPIER_H
 #define BLOCK_CACHE_COPIER_H
 
-#include "block_cache.h"
+#include "block-cache/io_engine.h"
+#include "block-cache/mem_pool.h"
 
 #include <string>
+#include <list>
+#include <map>
 
 //----------------------------------------------------------------
 
 namespace bcache {
+	using block_address = uint64_t;
+
+	struct copy_op {
+		copy_op()
+			: read_complete(false),
+			  write_complete(false) {
+		}
+
+		block_address src_b, src_e;
+		block_address dest_b;
+
+		bool read_complete;
+		bool write_complete;
+	};
+
+	class copy_job {
+	public:
+		copy_job(copy_op const &op_, void *data_)
+			: op(op_), data(data_) {
+		}
+
+		copy_op op;
+		void *data;
+	};
+
 	class copier {
 	public:
-		// block size in sectors
 		copier(std::string const &src, std::string const &dest,
-		       unsigned block_size);
-		~copier();
+		       sector_t block_size, size_t mem);
 
-		// Returns the number of sectors copied
-		unsigned copy(block_address from, block_address to);
+		sector_t get_block_size() const {
+			return block_size_;
+		}
 
-		unsigned get_block_size() const;
+		// Blocks if out of memory.
+		void issue(copy_op const &op);
+
+		unsigned nr_pending() const;
+		boost::optional<copy_op> wait();
 
 	private:
-		unsigned block_size_;
+		void wait_();
+		void complete(copy_job const &j);
+
+		sector_t to_sector(block_address b) const;
+		unsigned genkey();
+
+		mempool pool_;
+		sector_t block_size_;
+		unsigned nr_blocks_;
+		io_engine engine_;
+		io_engine::handle src_handle_;
+		io_engine::handle dest_handle_;
+		unsigned genkey_count_;
+
+		using job_map = std::map<unsigned, copy_job>;
+		using op_list = std::list<copy_op>;
+		job_map jobs_;
+		op_list complete_;
 	};
 }