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Commit 16786454 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Nicholas Bellinger
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tcm_loop: switch to using transport_handle_cdb_direct 



Now that we use a workqueue for I/O submission there is no need to use
transport_generic_handle_cdb_map any more.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
parent afe2cb7f

drivers/target/loopback/tcm_loop.c

+56 −56
Original line number Diff line number Diff line
@@ -49,59 +49,7 @@ static struct kmem_cache *tcm_loop_cmd_cache; 


static int tcm_loop_hba_no_cnt;



/*

 * Called by struct target_core_fabric_ops->new_cmd_map()

 *

 * Always called in process context.  A non zero return value

 * here will signal to handle an exception based on the return code.

 */

static int tcm_loop_new_cmd_map(struct se_cmd *se_cmd)

{

	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,

				struct tcm_loop_cmd, tl_se_cmd);

	struct scsi_cmnd *sc = tl_cmd->sc;

	struct scatterlist *sgl_bidi = NULL;

	u32 sgl_bidi_count = 0;

	int ret;

	/*

	 * Allocate the necessary tasks to complete the received CDB+data

	 */

	ret = transport_generic_allocate_tasks(se_cmd, sc->cmnd);

	if (ret != 0)

		return ret;

	/*

	 * For BIDI commands, pass in the extra READ buffer

	 * to transport_generic_map_mem_to_cmd() below..

	 */

	if (se_cmd->se_cmd_flags & SCF_BIDI) {

		struct scsi_data_buffer *sdb = scsi_in(sc);



		sgl_bidi = sdb->table.sgl;

		sgl_bidi_count = sdb->table.nents;

	}

	/*

	 * Because some userspace code via scsi-generic do not memset their

	 * associated read buffers, go ahead and do that here for type

	 * SCF_SCSI_CONTROL_SG_IO_CDB.  Also note that this is currently

	 * guaranteed to be a single SGL for SCF_SCSI_CONTROL_SG_IO_CDB

	 * by target core in transport_generic_allocate_tasks() ->

	 * transport_generic_cmd_sequencer().

	 */

	if (se_cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB &&

	    se_cmd->data_direction == DMA_FROM_DEVICE) {

		struct scatterlist *sg = scsi_sglist(sc);

		unsigned char *buf = kmap(sg_page(sg)) + sg->offset;



		if (buf != NULL) {

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

			kunmap(sg_page(sg));

		}

	}



	/* Tell the core about our preallocated memory */

	return transport_generic_map_mem_to_cmd(se_cmd, scsi_sglist(sc),

			scsi_sg_count(sc), sgl_bidi, sgl_bidi_count);

}

static int tcm_loop_queue_status(struct se_cmd *se_cmd);



/*

 * Called from struct target_core_fabric_ops->check_stop_free()
@@ -216,6 +164,9 @@ static void tcm_loop_submission_work(struct work_struct *work) 
	struct tcm_loop_nexus *tl_nexus;

	struct tcm_loop_hba *tl_hba;

	struct tcm_loop_tpg *tl_tpg;

	struct scatterlist *sgl_bidi = NULL;

	u32 sgl_bidi_count = 0;

	int ret;



	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);

	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
@@ -242,16 +193,66 @@ static void tcm_loop_submission_work(struct work_struct *work) 
			scsi_bufflen(sc), sc->sc_data_direction,

			tcm_loop_sam_attr(sc), &tl_cmd->tl_sense_buf[0]);



	if (scsi_bidi_cmnd(sc))

	if (scsi_bidi_cmnd(sc)) {

		struct scsi_data_buffer *sdb = scsi_in(sc);



		sgl_bidi = sdb->table.sgl;

		sgl_bidi_count = sdb->table.nents;

		se_cmd->se_cmd_flags |= SCF_BIDI;



	}



	if (transport_lookup_cmd_lun(se_cmd, tl_cmd->sc->device->lun) < 0) {

		kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);

		set_host_byte(sc, DID_NO_CONNECT);

		goto out_done;

	}



	transport_generic_handle_cdb_map(se_cmd);

	/*

	 * Because some userspace code via scsi-generic do not memset their

	 * associated read buffers, go ahead and do that here for type

	 * SCF_SCSI_CONTROL_SG_IO_CDB.  Also note that this is currently

	 * guaranteed to be a single SGL for SCF_SCSI_CONTROL_SG_IO_CDB

	 * by target core in transport_generic_allocate_tasks() ->

	 * transport_generic_cmd_sequencer().

	 */

	if (se_cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB &&

	    se_cmd->data_direction == DMA_FROM_DEVICE) {

		struct scatterlist *sg = scsi_sglist(sc);

		unsigned char *buf = kmap(sg_page(sg)) + sg->offset;



		if (buf != NULL) {

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

			kunmap(sg_page(sg));

		}

	}



	ret = transport_generic_allocate_tasks(se_cmd, sc->cmnd);

	if (ret == -ENOMEM) {

		transport_send_check_condition_and_sense(se_cmd,

				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);

		transport_generic_free_cmd(se_cmd, 0);

		return;

	}

	if (ret == -EINVAL) {

		if (se_cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)

			tcm_loop_queue_status(se_cmd);

		else

			transport_send_check_condition_and_sense(se_cmd,

					se_cmd->scsi_sense_reason, 0);

		transport_generic_free_cmd(se_cmd, 0);

		return;

	}



	ret = transport_generic_map_mem_to_cmd(se_cmd, scsi_sglist(sc),

			scsi_sg_count(sc), sgl_bidi, sgl_bidi_count);

	if (ret) {

		transport_send_check_condition_and_sense(se_cmd,

					se_cmd->scsi_sense_reason, 0);

		transport_generic_free_cmd(se_cmd, 0);

		return;

	}

	transport_handle_cdb_direct(se_cmd);

	return;



out_done:
@@ -1380,7 +1381,6 @@ static int tcm_loop_register_configfs(void) 
	/*

	 * Used for setting up remaining TCM resources in process context

	 */

	fabric->tf_ops.new_cmd_map = &tcm_loop_new_cmd_map;

	fabric->tf_ops.check_stop_free = &tcm_loop_check_stop_free;

	fabric->tf_ops.release_cmd = &tcm_loop_release_cmd;

	fabric->tf_ops.shutdown_session = &tcm_loop_shutdown_session;