From e05ccafd6ee214895d01efbb13a3757e3625a859 Mon Sep 17 00:00:00 2001 From: Mikhail Pershin Date: Wed, 15 Jul 2020 08:42:49 +0300 Subject: [PATCH] LU-13763 osc: don't allow negative grants Add check in the osc_init_grant() to prevent possible underflow of cl_avail_grant and report error if it happens Signed-off-by: Mikhail Pershin Change-Id: Idcd25ed427c23735e1cdc70359bace43b5b9d886 Reviewed-on: https://review.whamcloud.com/39827 Reviewed-by: Andreas Dilger Tested-by: jenkins Tested-by: Maloo Reviewed-by: Olaf Faaland-LLNL Reviewed-by: Vladimir Saveliev Reviewed-by: Li Dongyang Reviewed-by: Oleg Drokin --- lustre/osc/osc_request.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/lustre/osc/osc_request.c b/lustre/osc/osc_request.c index 1acf2d1..290f26f 100644 --- a/lustre/osc/osc_request.c +++ b/lustre/osc/osc_request.c @@ -1023,12 +1023,19 @@ 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)) { -- 1.8.3.1