From 1f48b065dad168eebc4f184e97d4aab7a732bd6a Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Sat, 27 Feb 2021 10:59:53 -0600 Subject: [PATCH] scsi: target: xen-scsiback: Convert to new submission API target_submit_cmd_map_sgls() is being removed, so convert xen to the new submission API. This has it use target_init_cmd(), target_submit_prep(), or target_submit() because we need to have LIO core map sgls which is now done in target_submit_prep(). target_init_cmd() will never fail for xen because it does its own sync during session shutdown, so we can remove that code. Note: xen never calls target_stop_session() so target_submit_cmd_map_sgls() never failed (in the new API target_init_cmd() handles target_stop_session() being called when cmds are being submitted). If it were to have used target_stop_session() and got an error, we would have hit a refcount bug like xen and usb, because it does: if (rc < 0) { transport_send_check_condition_and_sense(se_cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0); transport_generic_free_cmd(se_cmd, 0); } transport_send_check_condition_and_sense() calls queue_status which calls scsiback_cmd_done->target_put_sess_cmd. We do an extra transport_generic_free_cmd() call above which would have dropped the refcount to -1 and the refcount code would spit out errors. Link: https://lore.kernel.org/r/20210227170006.5077-13-michael.christie@oracle.com Reviewed-by: Christoph Hellwig Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen --- drivers/xen/xen-scsiback.c | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-) diff --git a/drivers/xen/xen-scsiback.c b/drivers/xen/xen-scsiback.c index f3024942fbdf..18b9549f6fa3 100644 --- a/drivers/xen/xen-scsiback.c +++ b/drivers/xen/xen-scsiback.c @@ -360,21 +360,18 @@ static void scsiback_cmd_exec(struct vscsibk_pend *pending_req) { struct se_cmd *se_cmd = &pending_req->se_cmd; struct se_session *sess = pending_req->v2p->tpg->tpg_nexus->tvn_se_sess; - int rc; scsiback_get(pending_req->info); se_cmd->tag = pending_req->rqid; - rc = target_submit_cmd_map_sgls(se_cmd, sess, pending_req->cmnd, - pending_req->sense_buffer, pending_req->v2p->lun, - pending_req->data_len, 0, - pending_req->sc_data_direction, TARGET_SCF_ACK_KREF, - pending_req->sgl, pending_req->n_sg, - NULL, 0, NULL, 0); - if (rc < 0) { - transport_send_check_condition_and_sense(se_cmd, - TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0); - transport_generic_free_cmd(se_cmd, 0); - } + target_init_cmd(se_cmd, sess, pending_req->sense_buffer, + pending_req->v2p->lun, pending_req->data_len, 0, + pending_req->sc_data_direction, TARGET_SCF_ACK_KREF); + + if (target_submit_prep(se_cmd, pending_req->cmnd, pending_req->sgl, + pending_req->n_sg, NULL, 0, NULL, 0)) + return; + + target_submit(se_cmd); } static int scsiback_gnttab_data_map_batch(struct gnttab_map_grant_ref *map,