target: Enable WRITE_INSERT emulation in target_execute_cmd

This patch enables WRITE_INSERT emulation in target_execute_cmd() in order to locally generate DIF PI before submitting the WRITE to the underlying backend device. This is required for fabric drivers that currently don't support DIF over-the-wire, in order to inact with backend devices that have hardware (IBLOCK) or software (FILEIO + RAMDISK) support for handling T10 PI. v2 changes: - Convert to sbc_dif_generate() usage (Sagi) Reviewed-by: Sagi Grimberg <[email protected]> Cc: Martin K. Petersen <[email protected]> Cc: Or Gerlitz <[email protected]> Cc: Quinn Tran <[email protected]> Cc: Giridhar Malavali <[email protected]> Signed-off-by: Nicholas Bellinger <[email protected]>
mrcsosa · Apr 7, 2014 · a84bf9e · a84bf9e
1 parent 66a3d5b
commit a84bf9e
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
@@ -1767,6 +1767,15 @@ void target_execute_cmd(struct se_cmd *cmd)
 	cmd->t_state = TRANSPORT_PROCESSING;
 	cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
 	spin_unlock_irq(&cmd->t_state_lock);
+	/*
+	 * Perform WRITE_INSERT of PI using software emulation when backend
+	 * device has PI enabled, if the transport has not already generated
+	 * PI using hardware WRITE_INSERT offload.
+	 */
+	if (cmd->prot_op == TARGET_PROT_DOUT_INSERT) {
+		if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
+			sbc_dif_generate(cmd);
+	}
 
 	if (target_handle_task_attr(cmd)) {
 		spin_lock_irq(&cmd->t_state_lock);