rgw: remove unnecessary loop in rgw_get_system_obj()

the call to read() is no longer limited to 'request_len', so we don't
need to reallocate/retry

there's no reason to issue a separate stat() call either

Signed-off-by: Casey Bodley <cbodley@redhat.com>

src/rgw/rgw_tools.cc

@@ -154,55 +154,21 @@ int rgw_stat_system_obj(const DoutPrefixProvider *dpp, RGWSI_SysObj* svc_sysobj,
 
 
 int rgw_get_system_obj(RGWSI_SysObj* svc_sysobj, const rgw_pool& pool, const string& key, bufferlist& bl,
- RGWObjVersionTracker *objv_tracker, real_time *pmtime, optional_yield y, const DoutPrefixProvider *dpp, map<string, bufferlist> *pattrs,
+ RGWObjVersionTracker *objv_tracker, real_time *pmtime, optional_yield y,
+ const DoutPrefixProvider *dpp, map<string, bufferlist> *pattrs,
  rgw_cache_entry_info *cache_info,
  boost::optional<obj_version> refresh_version, bool raw_attrs)
 {
- bufferlist::iterator iter;
- int request_len = READ_CHUNK_LEN;
- rgw_raw_obj obj(pool, key);
-
- obj_version original_readv;
- if (objv_tracker && !objv_tracker->read_version.empty()) {
- original_readv = objv_tracker->read_version;
- }
-
- do {
- auto sysobj = svc_sysobj->get_obj(obj);
- auto rop = sysobj.rop();
-
- int ret = rop.set_attrs(pattrs)
- .set_last_mod(pmtime)
- .set_objv_tracker(objv_tracker)
- .set_raw_attrs(raw_attrs)
- .stat(y, dpp);
- if (ret < 0)
- return ret;
-
- ret = rop.set_cache_info(cache_info)
- .set_refresh_version(refresh_version)
- .read(dpp, &bl, y);
- if (ret == -ECANCELED) {
- /* raced, restart */
- if (!original_readv.empty()) {
- /* we were asked to read a specific obj_version, failed */
- return ret;
- }
- if (objv_tracker) {
- objv_tracker->read_version.clear();
- }
- continue;
- }
- if (ret < 0)
- return ret;
-
- if (ret < request_len)
- break;
- bl.clear();
- request_len *= 2;
- } while (true);
-
- return 0;
+ const rgw_raw_obj obj(pool, key);
+ auto sysobj = svc_sysobj->get_obj(obj);
+ auto rop = sysobj.rop();
+ return rop.set_attrs(pattrs)
+ .set_last_mod(pmtime)
+ .set_objv_tracker(objv_tracker)
+ .set_raw_attrs(raw_attrs)
+ .set_cache_info(cache_info)
+ .set_refresh_version(refresh_version)
+ .read(dpp, &bl, y);
 }
 
 int rgw_delete_system_obj(const DoutPrefixProvider *dpp,