Commit a84bf9ee authored Apr 02, 2014 by Nicholas Bellinger

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 <sagig@mellanox.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

parent 66a3d5bc

drivers/target/target_core_transport.c

+9 −0

Original line number	Diff line number	Diff line
		@@ -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);