@@ -3867,6 +3867,9 @@ static const struct target_core_fabric_ops srpt_template = {
.tfc_discovery_attrs = srpt_da_attrs,
.tfc_wwn_attrs = srpt_wwn_attrs,
.tfc_tpg_attrib_attrs = srpt_tpg_attrib_attrs,
+
+ .default_submit_type = TARGET_DIRECT_SUBMIT,
+ .direct_submit_supp = 1,
};
/**
@@ -1611,6 +1611,8 @@ static const struct target_core_fabric_ops efct_lio_ops = {
.sess_get_initiator_sid = NULL,
.tfc_tpg_base_attrs = efct_lio_tpg_attrs,
.tfc_tpg_attrib_attrs = efct_lio_tpg_attrib_attrs,
+ .default_submit_type = TARGET_DIRECT_SUBMIT,
+ .direct_submit_supp = 1,
};
static const struct target_core_fabric_ops efct_lio_npiv_ops = {
@@ -1646,6 +1648,9 @@ static const struct target_core_fabric_ops efct_lio_npiv_ops = {
.sess_get_initiator_sid = NULL,
.tfc_tpg_base_attrs = efct_lio_npiv_tpg_attrs,
.tfc_tpg_attrib_attrs = efct_lio_npiv_tpg_attrib_attrs,
+
+ .default_submit_type = TARGET_DIRECT_SUBMIT,
+ .direct_submit_supp = 1,
};
int efct_scsi_tgt_driver_init(void)
@@ -3975,6 +3975,9 @@ static const struct target_core_fabric_ops ibmvscsis_ops = {
.fabric_drop_tpg = ibmvscsis_drop_tpg,
.tfc_wwn_attrs = ibmvscsis_wwn_attrs,
+
+ .default_submit_type = TARGET_DIRECT_SUBMIT,
+ .direct_submit_supp = 1,
};
static void ibmvscsis_dev_release(struct device *dev) {};
@@ -1822,6 +1822,9 @@ static const struct target_core_fabric_ops tcm_qla2xxx_ops = {
.tfc_wwn_attrs = tcm_qla2xxx_wwn_attrs,
.tfc_tpg_base_attrs = tcm_qla2xxx_tpg_attrs,
.tfc_tpg_attrib_attrs = tcm_qla2xxx_tpg_attrib_attrs,
+
+ .default_submit_type = TARGET_DIRECT_SUBMIT,
+ .direct_submit_supp = 1,
};
static const struct target_core_fabric_ops tcm_qla2xxx_npiv_ops = {
@@ -1859,6 +1862,9 @@ static const struct target_core_fabric_ops tcm_qla2xxx_npiv_ops = {
.fabric_init_nodeacl = tcm_qla2xxx_init_nodeacl,
.tfc_wwn_attrs = tcm_qla2xxx_wwn_attrs,
+
+ .default_submit_type = TARGET_DIRECT_SUBMIT,
+ .direct_submit_supp = 1,
};
static int tcm_qla2xxx_register_configfs(void)
@@ -1590,4 +1590,7 @@ const struct target_core_fabric_ops iscsi_ops = {
.tfc_tpg_nacl_param_attrs = lio_target_nacl_param_attrs,
.write_pending_must_be_called = 1,
+
+ .default_submit_type = TARGET_DIRECT_SUBMIT,
+ .direct_submit_supp = 1,
};
@@ -1102,6 +1102,8 @@ static const struct target_core_fabric_ops loop_ops = {
.tfc_wwn_attrs = tcm_loop_wwn_attrs,
.tfc_tpg_base_attrs = tcm_loop_tpg_attrs,
.tfc_tpg_attrib_attrs = tcm_loop_tpg_attrib_attrs,
+ .default_submit_type = TARGET_QUEUE_SUBMIT,
+ .direct_submit_supp = 0,
};
static int __init tcm_loop_fabric_init(void)
@@ -2278,6 +2278,9 @@ static const struct target_core_fabric_ops sbp_ops = {
.tfc_wwn_attrs = sbp_wwn_attrs,
.tfc_tpg_base_attrs = sbp_tpg_base_attrs,
.tfc_tpg_attrib_attrs = sbp_tpg_attrib_attrs,
+
+ .default_submit_type = TARGET_DIRECT_SUBMIT,
+ .direct_submit_supp = 1,
};
static int __init sbp_init(void)
@@ -432,6 +432,9 @@ static const struct target_core_fabric_ops ft_fabric_ops = {
.tfc_wwn_attrs = ft_wwn_attrs,
.tfc_tpg_nacl_base_attrs = ft_nacl_base_attrs,
+
+ .default_submit_type = TARGET_DIRECT_SUBMIT,
+ .direct_submit_supp = 1,
};
static struct notifier_block ft_notifier = {
@@ -1687,6 +1687,9 @@ static const struct target_core_fabric_ops usbg_ops = {
.tfc_wwn_attrs = usbg_wwn_attrs,
.tfc_tpg_base_attrs = usbg_base_attrs,
+
+ .default_submit_type = TARGET_DIRECT_SUBMIT,
+ .direct_submit_supp = 1,
};
/* Start gadget.c code */
@@ -2598,6 +2598,9 @@ static const struct target_core_fabric_ops vhost_scsi_ops = {
.tfc_wwn_attrs = vhost_scsi_wwn_attrs,
.tfc_tpg_base_attrs = vhost_scsi_tpg_attrs,
.tfc_tpg_attrib_attrs = vhost_scsi_tpg_attrib_attrs,
+
+ .default_submit_type = TARGET_QUEUE_SUBMIT,
+ .direct_submit_supp = 1,
};
static int __init vhost_scsi_init(void)
@@ -1832,6 +1832,9 @@ static const struct target_core_fabric_ops scsiback_ops = {
.tfc_wwn_attrs = scsiback_wwn_attrs,
.tfc_tpg_base_attrs = scsiback_tpg_attrs,
.tfc_tpg_param_attrs = scsiback_param_attrs,
+
+ .default_submit_type = TARGET_DIRECT_SUBMIT,
+ .direct_submit_supp = 1,
};
static const struct xenbus_device_id scsiback_ids[] = {
@@ -108,6 +108,15 @@
#define SE_MODE_PAGE_BUF 512
#define SE_SENSE_BUF 96
+enum target_submit_type {
+ /* Use the fabric driver's default submission type */
+ TARGET_FABRIC_DEFAULT_SUBMIT,
+ /* Submit from the calling context */
+ TARGET_DIRECT_SUBMIT,
+ /* Defer submission to the LIO workqueue */
+ TARGET_QUEUE_SUBMIT,
+};
+
/* struct se_hba->hba_flags */
enum hba_flags_table {
HBA_FLAGS_INTERNAL_USE = 0x01,
@@ -118,6 +118,15 @@ struct target_core_fabric_ops {
* its entirety before a command is aborted.
*/
unsigned int write_pending_must_be_called:1;
+ /*
+ * Set this if the driver supports submitting commands to the backend
+ * from target_submit/target_submit_cmd.
+ */
+ unsigned int direct_submit_supp:1;
+ /*
+ * Set this to a target_submit_type value.
+ */
+ u8 default_submit_type;
};
int target_register_template(const struct target_core_fabric_ops *fo);
In some cases, like with multiple LUN targets or where the target has to respond to transport level requests from the receiving context it can be better to defer cmd submission to a helper thread. If the backend driver blocks on something like request/tag allocation it can block the entire target submission path and other LUs and transport IO on that session. In other cases like single LUN targets with storage that can support all the commands that the target can queue, then it's best to submit the cmd to the backend from the target's cmd receiving context. The next patches will allow the user to config what they prefer, but drivers like loop can't directly submit because they can be called from a context that can't sleep. And, drivers like vhost-scsi can support direct submission, but need to keep their default behavior of deferring execution to avoid possible regressions where the backend can block. This patch has the drivers tell LIO core if they support direct submissions and their current default, so in the next patch we can prevent users from misconfiguring the system and initialize devices correctly. Signed-off-by: Mike Christie <michael.christie@oracle.com> --- drivers/infiniband/ulp/srpt/ib_srpt.c | 3 +++ drivers/scsi/elx/efct/efct_lio.c | 5 +++++ drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c | 3 +++ drivers/scsi/qla2xxx/tcm_qla2xxx.c | 6 ++++++ drivers/target/iscsi/iscsi_target_configfs.c | 3 +++ drivers/target/loopback/tcm_loop.c | 2 ++ drivers/target/sbp/sbp_target.c | 3 +++ drivers/target/tcm_fc/tfc_conf.c | 3 +++ drivers/usb/gadget/function/f_tcm.c | 3 +++ drivers/vhost/scsi.c | 3 +++ drivers/xen/xen-scsiback.c | 3 +++ include/target/target_core_base.h | 9 +++++++++ include/target/target_core_fabric.h | 9 +++++++++ 13 files changed, 55 insertions(+)