LU-17200 mdt: check object's locality

remote object can disappear while we're getting an ldlm lock for
it. we can't check object's attributes before we're sure it does
exist. so check object's locality first.

Signed-off-by: Alex Zhuravlev <bzzz@whamcloud.com>
Change-Id: I86ad0f3e7c38b0dce51a9fd836ba2293b210fe4f
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/52716
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Mikhail Pershin <mpershin@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>

diff --git a/lustre/mdt/mdt_handler.c b/lustre/mdt/mdt_handler.c
index 794ed24..19e05d0 100644 (file)
--- a/lustre/mdt/mdt_handler.c
+++ b/lustre/mdt/mdt_handler.c
@@ -2465,8 +2465,13 @@ static int mdt_getattr_name_lock(struct mdt_thread_info *info,
                        ldlm_set_ast_sent(lock);
                }
 
-               if (S_ISREG(lu_object_attr(&child->mot_obj)) &&
-                   !mdt_object_remote(child) && child != parent) {
+               /*
+                * check whether the object is remote as we can't
+                * really check attributes w/o explicit check for
+                * object's existence first.
+                */
+               if (!mdt_object_remote(child) && child != parent &&
+                   S_ISREG(lu_object_attr(&child->mot_obj))) {
                        mdt_object_put(info->mti_env, child);
                        rc = mdt_pack_size2body(info, child_fid,
                                                &lhc->mlh_reg_lh);