libceph: specify position of extent operation

allow specifying position of extent operation in multi-operations
osd request. This is required for cephfs to convert inline data to
normal data (compare xattr, then write object).

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@redhat.com>
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index d7e0da8..c03ac4c 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -598,7 +598,7 @@
 		snapc = ci->i_snap_realm->cached_context;
 		vino = ceph_vino(inode);
 		req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
-					    vino, pos, &len,
+					    vino, pos, &len, 0,
 					    2,/*include a 'startsync' command*/
 					    CEPH_OSD_OP_WRITE, flags, snapc,
 					    ci->i_truncate_seq,
@@ -609,6 +609,8 @@
 			break;
 		}
 
+		osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC);
+
 		n = iov_iter_get_pages_alloc(from, &pages, len, &start);
 		if (unlikely(n < 0)) {
 			ret = n;
@@ -713,7 +715,7 @@
 		snapc = ci->i_snap_realm->cached_context;
 		vino = ceph_vino(inode);
 		req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
-					    vino, pos, &len, 1,
+					    vino, pos, &len, 0, 1,
 					    CEPH_OSD_OP_WRITE, flags, snapc,
 					    ci->i_truncate_seq,
 					    ci->i_truncate_size,
@@ -1111,7 +1113,7 @@
 	req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
 					ceph_vino(inode),
 					offset, length,
-					1, op,
+					0, 1, op,
 					CEPH_OSD_FLAG_WRITE |
 					CEPH_OSD_FLAG_ONDISK,
 					NULL, 0, 0, false);