LU-11956 mdd: do not reset original lu_buf.lb_len

In mdd_iterate_xattrs(), we are resetting the xbuf.lb_len
to a smaller value returned by linkea_overflow_shrink().

If that's the last xattr we gonna process, we could deduct
less than originally allocated size from obd_memory stats,
failing the memleak check later.

Lustre-change: https://review.whamcloud.com/35333
Lustre-commit: 94a5bc1bcb6c6373ead5b091ff5915dfe452377b

Signed-off-by: Li Dongyang <dongyangli@ddn.com>
Change-Id: I6175a91c61ceb0e37ab889d0cfd904f4993ab5cc
Reviewed-on: https://review.whamcloud.com/37029
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>

diff --git a/lustre/mdd/mdd_dir.c b/lustre/mdd/mdd_dir.c
index 79e9acb..6594873 100644 (file)
--- a/lustre/mdd/mdd_dir.c
+++ b/lustre/mdd/mdd_dir.c
@@ -3507,6 +3507,7 @@ static int mdd_iterate_xattrs(const struct lu_env *env,
        struct mdd_thread_info *info = mdd_env_info(env);
        char *xname;
        struct lu_buf list_xbuf;
+       struct lu_buf cbxbuf;
        struct lu_buf xbuf = { NULL };
        int list_xsize;
        int xlen;
@@ -3563,14 +3564,15 @@ static int mdd_iterate_xattrs(const struct lu_env *env,
                if (rc < 0)
                        GOTO(out, rc);
 
+               cbxbuf = xbuf;
 repeat:
-               rc = cb(env, tobj, &xbuf, xname, 0, handle);
+               rc = cb(env, tobj, &cbxbuf, xname, 0, handle);
                if (unlikely(rc == -ENOSPC &&
                             strcmp(xname, XATTR_NAME_LINK) == 0)) {
                        rc = linkea_overflow_shrink(
-                                       (struct linkea_data *)(xbuf.lb_buf));
+                                       (struct linkea_data *)(cbxbuf.lb_buf));
                        if (likely(rc > 0)) {
-                               xbuf.lb_len = rc;
+                               cbxbuf.lb_len = rc;
                                goto repeat;
                        }
                }