rbd: use writefull op for object size writes

This covers only the simplest case - an object size sized write, but
it's still useful in tiering setups when EC is used for the base tier
as writefull op can be proxied, saving an object promotion.

Even though updating ceph_osdc_new_request() to allow writefull should
just be a matter of fixing an assert, I didn't do it because its only
user is cephfs.  All other sites were updated.

Reflects ceph.git commit 7bfb7f9025a8ee0d2305f49bf0336d2424da5b5b.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>

drivers/block/rbd.c

@@ -1863,9 +1863,11 @@ static void rbd_osd_req_callback(struct ceph_osd_request *osd_req,
 		rbd_osd_read_callback(obj_request);
 		break;
 	case CEPH_OSD_OP_SETALLOCHINT:
-		rbd_assert(osd_req->r_ops[1].op == CEPH_OSD_OP_WRITE);
+		rbd_assert(osd_req->r_ops[1].op == CEPH_OSD_OP_WRITE ||
+			   osd_req->r_ops[1].op == CEPH_OSD_OP_WRITEFULL);
 		/* fall through */
 	case CEPH_OSD_OP_WRITE:
+	case CEPH_OSD_OP_WRITEFULL:
 		rbd_osd_write_callback(obj_request);
 		break;
 	case CEPH_OSD_OP_STAT:
@@ -2401,7 +2403,10 @@ static void rbd_img_obj_request_fill(struct rbd_obj_request *obj_request,
 				opcode = CEPH_OSD_OP_ZERO;
 		}
 	} else if (op_type == OBJ_OP_WRITE) {
-		opcode = CEPH_OSD_OP_WRITE;
+		if (!offset && length == object_size)
+			opcode = CEPH_OSD_OP_WRITEFULL;
+		else
+			opcode = CEPH_OSD_OP_WRITE;
 		osd_req_op_alloc_hint_init(osd_request, num_ops,
 					object_size, object_size);
 		num_ops++;

net/ceph/osd_client.c

@@ -285,6 +285,7 @@ static void osd_req_op_data_release(struct ceph_osd_request *osd_req,
 	switch (op->op) {
 	case CEPH_OSD_OP_READ:
 	case CEPH_OSD_OP_WRITE:
+	case CEPH_OSD_OP_WRITEFULL:
 		ceph_osd_data_release(&op->extent.osd_data);
 		break;
 	case CEPH_OSD_OP_CALL:
@@ -485,13 +486,14 @@ void osd_req_op_extent_init(struct ceph_osd_request *osd_req,
 	size_t payload_len = 0;
 
 	BUG_ON(opcode != CEPH_OSD_OP_READ && opcode != CEPH_OSD_OP_WRITE &&
-	       opcode != CEPH_OSD_OP_ZERO && opcode != CEPH_OSD_OP_TRUNCATE);
+	       opcode != CEPH_OSD_OP_WRITEFULL && opcode != CEPH_OSD_OP_ZERO &&
+	       opcode != CEPH_OSD_OP_TRUNCATE);
 
 	op->extent.offset = offset;
 	op->extent.length = length;
 	op->extent.truncate_size = truncate_size;
 	op->extent.truncate_seq = truncate_seq;
-	if (opcode == CEPH_OSD_OP_WRITE)
+	if (opcode == CEPH_OSD_OP_WRITE || opcode == CEPH_OSD_OP_WRITEFULL)
 		payload_len += length;
 
 	op->payload_len = payload_len;
@@ -670,9 +672,11 @@ static u64 osd_req_encode_op(struct ceph_osd_request *req,
 		break;
 	case CEPH_OSD_OP_READ:
 	case CEPH_OSD_OP_WRITE:
+	case CEPH_OSD_OP_WRITEFULL:
 	case CEPH_OSD_OP_ZERO:
 	case CEPH_OSD_OP_TRUNCATE:
-		if (src->op == CEPH_OSD_OP_WRITE)
+		if (src->op == CEPH_OSD_OP_WRITE ||
+		    src->op == CEPH_OSD_OP_WRITEFULL)
 			request_data_len = src->extent.length;
 		dst->extent.offset = cpu_to_le64(src->extent.offset);
 		dst->extent.length = cpu_to_le64(src->extent.length);
@@ -681,7 +685,8 @@ static u64 osd_req_encode_op(struct ceph_osd_request *req,
 		dst->extent.truncate_seq =
 			cpu_to_le32(src->extent.truncate_seq);
 		osd_data = &src->extent.osd_data;
-		if (src->op == CEPH_OSD_OP_WRITE)
+		if (src->op == CEPH_OSD_OP_WRITE ||
+		    src->op == CEPH_OSD_OP_WRITEFULL)
 			ceph_osdc_msg_data_add(req->r_request, osd_data);
 		else
 			ceph_osdc_msg_data_add(req->r_reply, osd_data);