LU-13763 osc: don't allow negative grants

[fs/lustre-release.git] / lustre / osc / osc_request.c

diff --git a/lustre/osc/osc_request.c b/lustre/osc/osc_request.c
index 41fd462..f0660f4 100644 (file)
--- a/lustre/osc/osc_request.c
+++ b/lustre/osc/osc_request.c
@@ -964,12 +964,19 @@ void osc_init_grant(struct client_obd *cli, struct obd_connect_data *ocd)
        spin_lock(&cli->cl_loi_list_lock);
        cli->cl_avail_grant = ocd->ocd_grant;
        if (cli->cl_import->imp_state != LUSTRE_IMP_EVICTED) {
-               cli->cl_avail_grant -= cli->cl_reserved_grant;
+               unsigned long consumed = cli->cl_reserved_grant;
+
                if (OCD_HAS_FLAG(ocd, GRANT_PARAM))
-                       cli->cl_avail_grant -= cli->cl_dirty_grant;
+                       consumed += cli->cl_dirty_grant;
                else
-                       cli->cl_avail_grant -=
-                                       cli->cl_dirty_pages << PAGE_SHIFT;
+                       consumed += cli->cl_dirty_pages << PAGE_SHIFT;
+               if (cli->cl_avail_grant < consumed) {
+                       CERROR("%s: granted %ld but already consumed %ld\n",
+                              cli_name(cli), cli->cl_avail_grant, consumed);
+                       cli->cl_avail_grant = 0;
+               } else {
+                       cli->cl_avail_grant -= consumed;
+               }
        }
 
        if (OCD_HAS_FLAG(ocd, GRANT_PARAM)) {