From f872c9f417a38a08b6ffe46e1f937d3db1d22775 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 2 Feb 2012 17:04:40 -0500 Subject: [PATCH] tcm_loop: kill tcm_loop_allocate_core_cmd This function makes little sense as a separate abstraction as it's deeply interwinded with the control flow of its only caller. Merged it into tcm_loop_queuecommand after factoring out a helper to convert the task attribute representation. Signed-off-by: Christoph Hellwig Signed-off-by: Nicholas Bellinger --- drivers/target/loopback/tcm_loop.c | 147 ++++++++++++----------------- 1 file changed, 59 insertions(+), 88 deletions(-) diff --git a/drivers/target/loopback/tcm_loop.c b/drivers/target/loopback/tcm_loop.c index 7cfbcb00b3c3..b1edc517f4e3 100644 --- a/drivers/target/loopback/tcm_loop.c +++ b/drivers/target/loopback/tcm_loop.c @@ -48,81 +48,6 @@ static struct kmem_cache *tcm_loop_cmd_cache; static int tcm_loop_hba_no_cnt; -/* - * Allocate a tcm_loop cmd descriptor from target_core_mod code - * - * Can be called from interrupt context in tcm_loop_queuecommand() below - */ -static struct se_cmd *tcm_loop_allocate_core_cmd( - struct tcm_loop_hba *tl_hba, - struct se_portal_group *se_tpg, - struct scsi_cmnd *sc) -{ - struct se_cmd *se_cmd; - struct se_session *se_sess; - struct tcm_loop_nexus *tl_nexus = tl_hba->tl_nexus; - struct tcm_loop_cmd *tl_cmd; - int sam_task_attr; - - if (!tl_nexus) { - scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus" - " does not exist\n"); - set_host_byte(sc, DID_ERROR); - return NULL; - } - se_sess = tl_nexus->se_sess; - - tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC); - if (!tl_cmd) { - pr_err("Unable to allocate struct tcm_loop_cmd\n"); - set_host_byte(sc, DID_ERROR); - return NULL; - } - se_cmd = &tl_cmd->tl_se_cmd; - /* - * Save the pointer to struct scsi_cmnd *sc - */ - tl_cmd->sc = sc; - /* - * Locate the SAM Task Attr from struct scsi_cmnd * - */ - if (sc->device->tagged_supported) { - switch (sc->tag) { - case HEAD_OF_QUEUE_TAG: - sam_task_attr = MSG_HEAD_TAG; - break; - case ORDERED_QUEUE_TAG: - sam_task_attr = MSG_ORDERED_TAG; - break; - default: - sam_task_attr = MSG_SIMPLE_TAG; - break; - } - } else - sam_task_attr = MSG_SIMPLE_TAG; - - /* - * Initialize struct se_cmd descriptor from target_core_mod infrastructure - */ - transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, - scsi_bufflen(sc), sc->sc_data_direction, sam_task_attr, - &tl_cmd->tl_sense_buf[0]); - - if (scsi_bidi_cmnd(sc)) - se_cmd->se_cmd_flags |= SCF_BIDI; - - /* - * Locate the struct se_lun pointer and attach it to struct se_cmd - */ - 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); - return NULL; - } - - return se_cmd; -} - /* * Called by struct target_core_fabric_ops->new_cmd_map() * @@ -262,6 +187,25 @@ static int tcm_loop_change_queue_depth( return sdev->queue_depth; } +/* + * Locate the SAM Task Attr from struct scsi_cmnd * + */ +static int tcm_loop_sam_attr(struct scsi_cmnd *sc) +{ + if (sc->device->tagged_supported) { + switch (sc->tag) { + case HEAD_OF_QUEUE_TAG: + return MSG_HEAD_TAG; + case ORDERED_QUEUE_TAG: + return MSG_ORDERED_TAG; + default: + break; + } + } + + return MSG_SIMPLE_TAG; +} + /* * Main entry point from struct scsi_host_template for incoming SCSI CDB+Data * from Linux/SCSI subsystem for SCSI low level device drivers (LLDs) @@ -274,6 +218,10 @@ static int tcm_loop_queuecommand( struct se_portal_group *se_tpg; struct tcm_loop_hba *tl_hba; struct tcm_loop_tpg *tl_tpg; + struct se_session *se_sess; + struct tcm_loop_nexus *tl_nexus; + struct tcm_loop_cmd *tl_cmd; + pr_debug("tcm_loop_queuecommand() %d:%d:%d:%d got CDB: 0x%02x" " scsi_buf_len: %u\n", sc->device->host->host_no, @@ -290,24 +238,47 @@ static int tcm_loop_queuecommand( */ if (!tl_tpg->tl_hba) { set_host_byte(sc, DID_NO_CONNECT); - sc->scsi_done(sc); - return 0; + goto out_done; } se_tpg = &tl_tpg->tl_se_tpg; - /* - * Determine the SAM Task Attribute and allocate tl_cmd and - * tl_cmd->tl_se_cmd from TCM infrastructure - */ - se_cmd = tcm_loop_allocate_core_cmd(tl_hba, se_tpg, sc); - if (!se_cmd) { - sc->scsi_done(sc); - return 0; + + tl_nexus = tl_hba->tl_nexus; + if (!tl_nexus) { + scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus" + " does not exist\n"); + set_host_byte(sc, DID_ERROR); + goto out_done; } - /* - * Queue up the newly allocated to be processed in TCM thread context. - */ + se_sess = tl_nexus->se_sess; + + tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC); + if (!tl_cmd) { + pr_err("Unable to allocate struct tcm_loop_cmd\n"); + set_host_byte(sc, DID_ERROR); + goto out_done; + } + se_cmd = &tl_cmd->tl_se_cmd; + tl_cmd->sc = sc; + + transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, 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)) + 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); return 0; + +out_done: + sc->scsi_done(sc); + return 0; } /* -- 2.30.2