From 8f9f44f8957b262de717a48269a5ceca36c2b504 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Mon, 1 Oct 2012 23:29:49 -0700 Subject: [PATCH] tcm_loop: Convert I/O path to use target_submit_cmd_map_sgls This patch converts tcm_loop to use target_submit_cmd_map_sgls() for I/O submission and mapping of pre-allocated SGL memory from incoming scsi_cmnd -> se_cmd descriptors. This includes removing the original open-coded fabric uses of target core callers to support transport_generic_map_mem_to_cmd() between target_setup_cmd_from_cdb() and transport_handle_cdb_direct() logic. (v2: Use renamed target_submit_cmd_map_sgls) Reported-by: Christoph Hellwig Reviewed-by: Christoph Hellwig Signed-off-by: Nicholas Bellinger --- drivers/target/loopback/tcm_loop.c | 62 +++++--------------------------------- 1 file changed, 8 insertions(+), 54 deletions(-) diff --git a/drivers/target/loopback/tcm_loop.c b/drivers/target/loopback/tcm_loop.c index 7a0da1a..2d444b1 100644 --- a/drivers/target/loopback/tcm_loop.c +++ b/drivers/target/loopback/tcm_loop.c @@ -166,7 +166,7 @@ static void tcm_loop_submission_work(struct work_struct *work) struct tcm_loop_tpg *tl_tpg; struct scatterlist *sgl_bidi = NULL; u32 sgl_bidi_count = 0; - int ret; + int rc; tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host); tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id]; @@ -187,12 +187,6 @@ static void tcm_loop_submission_work(struct work_struct *work) set_host_byte(sc, DID_ERROR); goto out_done; } - - transport_init_se_cmd(se_cmd, tl_tpg->tl_se_tpg.se_tpg_tfo, - tl_nexus->se_sess, - scsi_bufflen(sc), sc->sc_data_direction, - tcm_loop_sam_attr(sc), &tl_cmd->tl_sense_buf[0]); - if (scsi_bidi_cmnd(sc)) { struct scsi_data_buffer *sdb = scsi_in(sc); @@ -201,56 +195,16 @@ static void tcm_loop_submission_work(struct work_struct *work) 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); + rc = target_submit_cmd_map_sgls(se_cmd, tl_nexus->se_sess, sc->cmnd, + &tl_cmd->tl_sense_buf[0], tl_cmd->sc->device->lun, + scsi_bufflen(sc), tcm_loop_sam_attr(sc), + sc->sc_data_direction, 0, + scsi_sglist(sc), scsi_sg_count(sc), + sgl_bidi, sgl_bidi_count); + if (rc < 0) { set_host_byte(sc, DID_NO_CONNECT); goto out_done; } - - /* - * Because some userspace code via scsi-generic do not memset their - * associated read buffers, 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) { - 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 = target_setup_cmd_from_cdb(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; - } else if (ret < 0) { - 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: -- 2.7.4