libceph: add osd_req_op_extent_osd_data_bvecs()

... and store num_bvecs for client code's convenience.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>

drivers/block/rbd.c

@@ -2366,7 +2366,9 @@ static int rbd_obj_issue_copyup(struct rbd_obj_request *obj_req, u32 bytes)
 	osd_req_op_cls_init(obj_req->osd_req, 0, CEPH_OSD_OP_CALL, "rbd",
 			    "copyup");
 	osd_req_op_cls_request_data_bvecs(obj_req->osd_req, 0,
-					  obj_req->copyup_bvecs, bytes);
+					  obj_req->copyup_bvecs,
+					  obj_req->copyup_bvec_count,
+					  bytes);
 
 	switch (obj_req->img_request->op_type) {
 	case OBJ_OP_WRITE:

include/linux/ceph/osd_client.h

@@ -77,7 +77,10 @@ struct ceph_osd_data {
 			u32			bio_length;
 		};
 #endif /* CONFIG_BLOCK */
-		struct ceph_bvec_iter	bvec_pos;
+		struct {
+			struct ceph_bvec_iter	bvec_pos;
+			u32			num_bvecs;
+		};
 	};
 };
 
@@ -412,6 +415,10 @@ void osd_req_op_extent_osd_data_bio(struct ceph_osd_request *osd_req,
 				    struct ceph_bio_iter *bio_pos,
 				    u32 bio_length);
 #endif /* CONFIG_BLOCK */
+void osd_req_op_extent_osd_data_bvecs(struct ceph_osd_request *osd_req,
+				      unsigned int which,
+				      struct bio_vec *bvecs, u32 num_bvecs,
+				      u32 bytes);
 void osd_req_op_extent_osd_data_bvec_pos(struct ceph_osd_request *osd_req,
 					 unsigned int which,
 					 struct ceph_bvec_iter *bvec_pos);
@@ -426,7 +433,8 @@ extern void osd_req_op_cls_request_data_pages(struct ceph_osd_request *,
 					bool own_pages);
 void osd_req_op_cls_request_data_bvecs(struct ceph_osd_request *osd_req,
 				       unsigned int which,
-				       struct bio_vec *bvecs, u32 bytes);
+				       struct bio_vec *bvecs, u32 num_bvecs,
+				       u32 bytes);
 extern void osd_req_op_cls_response_data_pages(struct ceph_osd_request *,
 					unsigned int which,
 					struct page **pages, u64 length,

net/ceph/osd_client.c

@@ -157,10 +157,12 @@ static void ceph_osd_data_bio_init(struct ceph_osd_data *osd_data,
 #endif /* CONFIG_BLOCK */
 
 static void ceph_osd_data_bvecs_init(struct ceph_osd_data *osd_data,
-				     struct ceph_bvec_iter *bvec_pos)
+				     struct ceph_bvec_iter *bvec_pos,
+				     u32 num_bvecs)
 {
 	osd_data->type = CEPH_OSD_DATA_TYPE_BVECS;
 	osd_data->bvec_pos = *bvec_pos;
+	osd_data->num_bvecs = num_bvecs;
 }
 
 #define osd_req_op_data(oreq, whch, typ, fld)				\
@@ -237,6 +239,22 @@ void osd_req_op_extent_osd_data_bio(struct ceph_osd_request *osd_req,
 EXPORT_SYMBOL(osd_req_op_extent_osd_data_bio);
 #endif /* CONFIG_BLOCK */
 
+void osd_req_op_extent_osd_data_bvecs(struct ceph_osd_request *osd_req,
+				      unsigned int which,
+				      struct bio_vec *bvecs, u32 num_bvecs,
+				      u32 bytes)
+{
+	struct ceph_osd_data *osd_data;
+	struct ceph_bvec_iter it = {
+		.bvecs = bvecs,
+		.iter = { .bi_size = bytes },
+	};
+
+	osd_data = osd_req_op_data(osd_req, which, extent, osd_data);
+	ceph_osd_data_bvecs_init(osd_data, &it, num_bvecs);
+}
+EXPORT_SYMBOL(osd_req_op_extent_osd_data_bvecs);
+
 void osd_req_op_extent_osd_data_bvec_pos(struct ceph_osd_request *osd_req,
 					 unsigned int which,
 					 struct ceph_bvec_iter *bvec_pos)
@@ -244,7 +262,7 @@ void osd_req_op_extent_osd_data_bvec_pos(struct ceph_osd_request *osd_req,
 	struct ceph_osd_data *osd_data;
 
 	osd_data = osd_req_op_data(osd_req, which, extent, osd_data);
-	ceph_osd_data_bvecs_init(osd_data, bvec_pos);
+	ceph_osd_data_bvecs_init(osd_data, bvec_pos, 0);
 }
 EXPORT_SYMBOL(osd_req_op_extent_osd_data_bvec_pos);
 
@@ -287,7 +305,8 @@ EXPORT_SYMBOL(osd_req_op_cls_request_data_pages);
 
 void osd_req_op_cls_request_data_bvecs(struct ceph_osd_request *osd_req,
 				       unsigned int which,
-				       struct bio_vec *bvecs, u32 bytes)
+				       struct bio_vec *bvecs, u32 num_bvecs,
+				       u32 bytes)
 {
 	struct ceph_osd_data *osd_data;
 	struct ceph_bvec_iter it = {
@@ -296,7 +315,7 @@ void osd_req_op_cls_request_data_bvecs(struct ceph_osd_request *osd_req,
 	};
 
 	osd_data = osd_req_op_data(osd_req, which, cls, request_data);
-	ceph_osd_data_bvecs_init(osd_data, &it);
+	ceph_osd_data_bvecs_init(osd_data, &it, num_bvecs);
 	osd_req->r_ops[which].cls.indata_len += bytes;
 	osd_req->r_ops[which].indata_len += bytes;
 }