rbd: separate layout init

Pull a block of code that initializes the layout structure in an osd
request into its own function so it can be reused.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 0fbe9ad..d4e93a2 100644 (file)
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -54,6 +54,7 @@
 
 /* It might be useful to have this defined elsewhere too */
 
+#define        U32_MAX ((u32) (~0U))
 #define        U64_MAX ((u64) (~0ULL))
 
 #define RBD_DRV_NAME "rbd"
@@ -1096,6 +1097,16 @@ static void rbd_coll_end_req(struct rbd_request *rbd_req,
                                ret, len);
 }
 
+static void rbd_layout_init(struct ceph_file_layout *layout, u64 pool_id)
+{
+       memset(layout, 0, sizeof (*layout));
+       layout->fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
+       layout->fl_stripe_count = cpu_to_le32(1);
+       layout->fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
+       rbd_assert(pool_id <= (u64) U32_MAX);
+       layout->fl_pg_pool = cpu_to_le32((u32) pool_id);
+}
+
 /*
  * Send ceph osd request
  */
@@ -1117,7 +1128,6 @@ static int rbd_do_request(struct request *rq,
                          u64 *ver)
 {
        struct ceph_osd_request *osd_req;
-       struct ceph_file_layout *layout;
        int ret;
        u64 bno;
        struct timespec mtime = CURRENT_TIME;
@@ -1161,14 +1171,9 @@ static int rbd_do_request(struct request *rq,
        strncpy(osd_req->r_oid, object_name, sizeof(osd_req->r_oid));
        osd_req->r_oid_len = strlen(osd_req->r_oid);
 
-       layout = &osd_req->r_file_layout;
-       memset(layout, 0, sizeof(*layout));
-       layout->fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
-       layout->fl_stripe_count = cpu_to_le32(1);
-       layout->fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
-       layout->fl_pg_pool = cpu_to_le32((int) rbd_dev->spec->pool_id);
-       ret = ceph_calc_raw_layout(osdc, layout, snapid, ofs, &len, &bno,
-                                  osd_req, ops);
+       rbd_layout_init(&osd_req->r_file_layout, rbd_dev->spec->pool_id);
+       ret = ceph_calc_raw_layout(osdc, &osd_req->r_file_layout,
+                               snapid, ofs, &len, &bno, osd_req, ops);
        rbd_assert(ret == 0);
 
        ceph_osdc_build_request(osd_req, ofs, &len,