diff --git a/Makefile.in b/Makefile.in
index 31ba2f7..97b86c4 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -129,6 +129,7 @@ DEVTOOLS_SOURCE=\
 	thin-provisioning/thin_ll_restore.cc \
 	thin-provisioning/thin_show_duplicates.cc \
 	thin-provisioning/thin_generate_metadata.cc \
+	thin-provisioning/thin_generate_mappings.cc \
 	thin-provisioning/variable_chunk_stream.cc \
 	thin-provisioning/thin_show_metadata.cc \
 	thin-provisioning/thin_scan.cc \
diff --git a/thin-provisioning/commands.cc b/thin-provisioning/commands.cc
index 13dc76c..23f4b0e 100644
--- a/thin-provisioning/commands.cc
+++ b/thin-provisioning/commands.cc
@@ -23,6 +23,7 @@ thin_provisioning::register_thin_commands(base::application &app)
 	app.add_cmd(command::ptr(new thin_ll_restore_cmd()));
 	app.add_cmd(command::ptr(new thin_scan_cmd()));
 	app.add_cmd(command::ptr(new thin_generate_metadata_cmd()));
+	app.add_cmd(command::ptr(new thin_generate_mappings_cmd()));
 	app.add_cmd(command::ptr(new thin_show_duplicates_cmd()));
 	app.add_cmd(command::ptr(new thin_show_metadata_cmd()));
 	app.add_cmd(command::ptr(new thin_journal_cmd()));
diff --git a/thin-provisioning/commands.h b/thin-provisioning/commands.h
index 6b80bdb..e3a41e7 100644
--- a/thin-provisioning/commands.h
+++ b/thin-provisioning/commands.h
@@ -110,6 +110,13 @@ namespace thin_provisioning {
 		virtual int run(int argc, char **argv);
 	};
 
+	class thin_generate_mappings_cmd : public base::command {
+	public:
+		thin_generate_mappings_cmd();
+		virtual void usage(std::ostream &out) const;
+		virtual int run(int argc, char **argv);
+	};
+
 	class thin_show_metadata_cmd : public base::command {
 	public:
 		thin_show_metadata_cmd();
diff --git a/thin-provisioning/thin_generate_mappings.cc b/thin-provisioning/thin_generate_mappings.cc
new file mode 100644
index 0000000..a366eba
--- /dev/null
+++ b/thin-provisioning/thin_generate_mappings.cc
@@ -0,0 +1,207 @@
+// This file is part of the thin-provisioning-tools source.
+//
+// thin-provisioning-tools is free software: you can redistribute it
+// and/or modify it under the terms of the GNU General Public License
+// as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// thin-provisioning-tools is distributed in the hope that it will be
+// useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+// of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with thin-provisioning-tools.  If not, see
+// <http://www.gnu.org/licenses/>.
+
+#include "base/io_generator.h"
+#include "base/output_file_requirements.h"
+#include "persistent-data/file_utils.h"
+#include "thin-provisioning/commands.h"
+#include "thin-provisioning/thin_pool.h"
+#include "version.h"
+
+#include <boost/optional.hpp>
+#include <getopt.h>
+#include <unistd.h>
+
+using namespace boost;
+using namespace thin_provisioning;
+
+//----------------------------------------------------------------
+
+namespace {
+	struct flags {
+		flags()
+			: pattern("write"),
+			  offset(0)
+		{
+		}
+
+		bool check_conformance();
+
+		boost::optional<string> output;
+		base::io_pattern pattern;
+		boost::optional<unsigned> dev_id;
+		boost::optional<base::sector_t> block_size;
+		base::sector_t offset;
+		boost::optional<base::sector_t> size;
+		boost::optional<base::sector_t> io_size;
+	};
+
+	bool flags::check_conformance() {
+		if (!output) {
+			cerr << "No output file provided." << endl;
+			return false;
+		}
+
+		if (!dev_id) {
+			cerr << "No device id provided." << endl;
+			return false;
+		}
+
+		if (!size) {
+			cerr << "No device size specified" << endl;
+			return false;
+		}
+
+		check_output_file_requirements(*output);
+
+		return true;
+	}
+
+	//--------------------------------
+
+	thin_pool::ptr open_pool(flags const &fs) {
+		block_manager::ptr bm = open_bm(*fs.output, block_manager::READ_WRITE);
+		return thin_pool::ptr(new thin_pool(bm));
+	}
+
+	int generate_mappings(flags const &fs) {
+		thin_pool::ptr pool = open_pool(fs);
+
+		thin::ptr td = pool->open_thin(*fs.dev_id);
+
+		io_generator_options opts;
+		opts.pattern_ = fs.pattern;
+		opts.block_size_ = !fs.block_size ?
+				   pool->get_data_block_size() :
+				   *fs.block_size;
+		opts.offset_ = fs.offset;
+		opts.size_ = *fs.size;
+		opts.io_size_ = !fs.io_size ? *fs.size : *fs.io_size;
+		io_generator::ptr gen = create_io_generator(opts);
+
+		base::io io;
+		while (gen->has_next()) {
+			// TODO: support io.size_
+			gen->next(io);
+
+			switch (io.op_) {
+			case base::REQ_OP_READ:
+				process_read(td, pool, io.sector_);
+				break;
+			case base::REQ_OP_WRITE:
+				process_write(td, pool, io.sector_);
+				break;
+			case base::REQ_OP_DISCARD:
+				process_discard(td, pool, io.sector_);
+				break;
+			}
+		}
+
+		pool->commit();
+
+		return 0;
+	}
+}
+
+//----------------------------------------------------------------
+
+thin_generate_mappings_cmd::thin_generate_mappings_cmd()
+	: command("thin_generate_mappings")
+{
+}
+
+void
+thin_generate_mappings_cmd::usage(std::ostream &out) const
+{
+	out << "Usage: " << get_name() << " [options]\n"
+	    << "Options:\n"
+	    << "  {-h|--help}\n"
+	    << "  {-o|--output} <output device or file>\n"
+	    << "  {--dev-id} <dev-id>\n"
+	    << "  {--offset} <offset>\n"
+            << "  {--io-size} <io_size>\n"
+	    << "  {--rw write|trim|randwrite|randtrim|randtw}\n"
+            << "  {--size} <size>\n"
+	    << "  {-V|--version}" << endl;
+}
+
+int
+thin_generate_mappings_cmd::run(int argc, char **argv)
+{
+	int c;
+	struct flags fs;
+	const char *shortopts = "hi:o:qV";
+	const struct option longopts[] = {
+		{ "help", no_argument, NULL, 'h' },
+		{ "output", required_argument, NULL, 'o' },
+		{ "dev-id", required_argument, NULL, 1 },
+		{ "rw", required_argument, NULL, 2 },
+		{ "offset", required_argument, NULL, 3 },
+		{ "size", required_argument, NULL, 4 },
+		{ "io-size", required_argument, NULL, 5 },
+		{ "version", no_argument, NULL, 'V' },
+		{ NULL, no_argument, NULL, 0 }
+	};
+
+	while ((c = getopt_long(argc, argv, shortopts, longopts, NULL)) != -1) {
+		switch(c) {
+		case 'h':
+			usage(cout);
+			return 0;
+
+		case 'o':
+			fs.output = optarg;
+			break;
+
+		case 1:
+			fs.dev_id = parse_uint64(optarg, "dev_id");
+			break;
+
+		case 2:
+			fs.pattern.parse(optarg);
+			break;
+
+		case 3:
+			fs.offset = parse_uint64(optarg, "offset");
+			break;
+
+		case 4:
+			fs.size = parse_uint64(optarg, "size");
+			break;
+
+		case 5:
+			fs.io_size = parse_uint64(optarg, "io_size");
+			break;
+
+		case 'V':
+			cout << THIN_PROVISIONING_TOOLS_VERSION << endl;
+			return 0;
+
+		default:
+			usage(cerr);
+			return 1;
+		}
+	}
+
+	if (!fs.check_conformance()) {
+		usage(cerr);
+		return 1;
+	}
+
+	return generate_mappings(fs);
+}
+
+//----------------------------------------------------------------