target: Add protected fabric + unprotected device support
This patch adds a new target_core_fabric_ops callback for allowing fabric
drivers to expose a TPG attribute for signaling when a T10-PI protected
fabric wants to function with an un-protected device without T10-PI.
This specifically is to allow LIO to perform WRITE_STRIP + READ_INSERT
operations when functioning with non T10-PI enabled devices, seperate
from any available hw offloads the fabric supports.
This is done using a new se_sess->sess_prot_type that is set at fabric
session creation time based upon the TPG attribute. It currently cannot
be changed for individual sessions after initial creation.
Also, update existing target_core_sbc.c code to honor sess_prot_type when
setting up cmd->prot_op + cmd->prot_type assignments.
(Add unlikely and !! boolean conversion in sbc_check_prot - Sagi)
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Doug Gilbert <dgilbert@interlog.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/include/target/target_core_fabric.h b/include/target/target_core_fabric.h
index 2f4a250..c93cfdf 100644
--- a/include/target/target_core_fabric.h
+++ b/include/target/target_core_fabric.h
@@ -27,6 +27,14 @@
* inquiry response
*/
int (*tpg_check_demo_mode_login_only)(struct se_portal_group *);
+ /*
+ * Optionally used as a configfs tunable to determine when
+ * target-core should signal the PROTECT=1 feature bit for
+ * backends that don't support T10-PI, so that either fabric
+ * HW offload or target-core emulation performs the associated
+ * WRITE_STRIP and READ_INSERT operations.
+ */
+ int (*tpg_check_prot_fabric_only)(struct se_portal_group *);
struct se_node_acl *(*tpg_alloc_fabric_acl)(
struct se_portal_group *);
void (*tpg_release_fabric_acl)(struct se_portal_group *,