Commit 5c48a4ea authored by Mike Christie's avatar Mike Christie Committed by Martin K. Petersen
Browse files

scsi: target: core: Move buffer clearing hack 



Move the hack to clear some buffers to transport_handle_cdb_direct() so we
can eventually merge transport_handle_cdb_direct() and target_submit().

This also fixes up the comment so it's clear it was only for udev and
reflects that the referenced function does not exist and we now allow more
than 1 page for control CDBs.

Signed-off-by: default avatarMike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20230928020907.5730-4-michael.christie@oracle.com


Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent ee48345e

drivers/target/target_core_transport.c

+21 −28
Original line number Diff line number Diff line
@@ -1592,6 +1592,27 @@ int transport_handle_cdb_direct( 
	 */

	core_alua_check_nonop_delay(cmd);



	if (cmd->t_data_nents != 0) {

		/*

		 * This is primarily a hack for udev and tcm loop which sends

		 * INQUIRYs with a single page and expects the data to be

		 * cleared.

		 */

		if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&

		    cmd->data_direction == DMA_FROM_DEVICE) {

			struct scatterlist *sgl = cmd->t_data_sg;

			unsigned char *buf = NULL;



			BUG_ON(!sgl);



			buf = kmap_local_page(sg_page(sgl));

			if (buf) {

				memset(buf + sgl->offset, 0, sgl->length);

				kunmap_local(buf);

			}

		}

	}



	if (!cmd->se_lun) {

		dump_stack();

		pr_err("cmd->se_lun is NULL\n");
@@ -1795,34 +1816,6 @@ EXPORT_SYMBOL_GPL(target_submit_prep); 
 */

void target_submit(struct se_cmd *se_cmd)

{

	struct scatterlist *sgl = se_cmd->t_data_sg;

	unsigned char *buf = NULL;



	might_sleep();



	if (se_cmd->t_data_nents != 0) {

		BUG_ON(!sgl);

		/*

		 * A work-around for tcm_loop as some userspace code via

		 * scsi-generic do not memset their associated read buffers,

		 * so go ahead and do that here for type non-data CDBs.  Also

		 * note that this is currently guaranteed to be a single SGL

		 * for this case by target core in target_setup_cmd_from_cdb()

		 * -> transport_generic_cmd_sequencer().

		 */

		if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&

		     se_cmd->data_direction == DMA_FROM_DEVICE) {

			if (sgl)

				buf = kmap(sg_page(sgl)) + sgl->offset;



			if (buf) {

				memset(buf, 0, sgl->length);

				kunmap(sg_page(sgl));

			}

		}



	}



	transport_handle_cdb_direct(se_cmd);

}

EXPORT_SYMBOL_GPL(target_submit);