Fill / persist all iovecs in FileDisk.request.

Change-Type: patch

lib/disk.js

@@ -36,12 +36,10 @@ class FileDisk extends EventEmitter {
 
 		switch (type) {
 			case constants.LKL_DEV_BLK_TYPE_READ:
-				// FIXME: we have to fill all the iovecs, not just the first
-				fs.read(this.fd, iovecs[0], 0, iovecs[0].length, offset, callback);
+				this._readWriteAllIovecs(fs.read, iovecs, offset, callback);
 				break;
 			case constants.LKL_DEV_BLK_TYPE_WRITE:
-				// FIXME: we have to persist all the iovecs, not just the first
-				fs.write(this.fd, iovecs[0], 0, iovecs[0].length, offset, callback);
+				this._readWriteAllIovecs(fs.write, iovecs, offset, callback);
 				break;
 			case constants.LKL_DEV_BLK_TYPE_FLUSH:
 			case constants.LKL_DEV_BLK_TYPE_FLUSH_OUT:
@@ -65,6 +63,35 @@ class FileDisk extends EventEmitter {
 			callback(null, stat.size);
 		});
 	};
+
+	_readWriteAllIovecs(fn, iovecs, offset, callback, iovecIndex) {
+		iovecIndex = (iovecIndex === undefined) ? 0 : iovecIndex;
+		fn(
+			this.fd,
+			iovecs[iovecIndex],
+			0,
+			iovecs[iovecIndex].length,
+			offset,
+			function(err, bytesCount, buf) {
+				if (err) {
+					// An error happened: errback.
+					callback(err.errno);
+				} else if (iovecIndex === iovecs.length - 1) {
+					// All iovecs are filled / persisted: callback.
+					callback(null);
+				} else {
+					// There are iovecs left: continue reading / writing.
+					this._readWriteAllIovecs(
+						fn,
+						iovecs,
+						offset + bytesCount,
+						callback,
+						iovecIndex + 1
+					);
+				}
+			}.bind(this)
+		);
+	};
 }
 
 exports.FileDisk = FileDisk;