Commit 8cefe07b authored Aug 25, 2013 by Nicholas Bellinger Committed by Nicholas Bellinger Sep 09, 2013

target: Do memory allocation for bidi commands using target_alloc_sgl



This patch updates transport_generic_new_cmd() to call target_alloc_sgl()
for SGL + page memory allocation for se_cmd->t_bidi_data_sg.

It also adds the special case for SCF_COMPARE_AND_WRITE to calculate a
different bidi_length based upon se_cmd->t_task_nolb.

Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>

parent 20093994

drivers/target/target_core_transport.c

+17 −0

Original line number	Diff line number	Diff line
		@@ -2149,6 +2149,23 @@ transport_generic_new_cmd(struct se_cmd *cmd)
		cmd->data_length) {
		bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);

		if ((cmd->se_cmd_flags & SCF_BIDI) \|\|
		(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
		u32 bidi_length;

		if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
		bidi_length = cmd->t_task_nolb *
		cmd->se_dev->dev_attrib.block_size;
		else
		bidi_length = cmd->data_length;

		ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
		&cmd->t_bidi_data_nents,
		bidi_length, zero_flag);
		if (ret < 0)
		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
		}

		ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
		cmd->data_length, zero_flag);
		if (ret < 0)