diff options
| -rw-r--r-- | drivers/target/loopback/tcm_loop.c | 97 | ||||
| -rw-r--r-- | drivers/target/loopback/tcm_loop.h | 2 |
2 files changed, 58 insertions, 41 deletions
diff --git a/drivers/target/loopback/tcm_loop.c b/drivers/target/loopback/tcm_loop.c index b1edc517f4e..cb8893f303a 100644 --- a/drivers/target/loopback/tcm_loop.c +++ b/drivers/target/loopback/tcm_loop.c @@ -44,6 +44,7 @@ /* Local pointer to allocated TCM configfs fabric module */ static struct target_fabric_configfs *tcm_loop_fabric_configfs; +static struct workqueue_struct *tcm_loop_workqueue; static struct kmem_cache *tcm_loop_cmd_cache; static int tcm_loop_hba_no_cnt; @@ -206,32 +207,19 @@ static int tcm_loop_sam_attr(struct scsi_cmnd *sc) 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) - */ -static int tcm_loop_queuecommand( - struct Scsi_Host *sh, - struct scsi_cmnd *sc) +static void tcm_loop_submission_work(struct work_struct *work) { - struct se_cmd *se_cmd; - struct se_portal_group *se_tpg; + struct tcm_loop_cmd *tl_cmd = + container_of(work, struct tcm_loop_cmd, work); + struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd; + struct scsi_cmnd *sc = tl_cmd->sc; + struct tcm_loop_nexus *tl_nexus; 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, - sc->device->id, sc->device->channel, sc->device->lun, - sc->cmnd[0], scsi_bufflen(sc)); - /* - * Locate the tcm_loop_hba_t pointer - */ tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host); tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id]; + /* * Ensure that this tl_tpg reference from the incoming sc->device->id * has already been configured via tcm_loop_make_naa_tpg(). @@ -240,7 +228,6 @@ static int tcm_loop_queuecommand( set_host_byte(sc, DID_NO_CONNECT); goto out_done; } - se_tpg = &tl_tpg->tl_se_tpg; tl_nexus = tl_hba->tl_nexus; if (!tl_nexus) { @@ -249,18 +236,9 @@ static int tcm_loop_queuecommand( set_host_byte(sc, DID_ERROR); goto out_done; } - 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, + 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]); @@ -274,10 +252,37 @@ static int tcm_loop_queuecommand( } transport_generic_handle_cdb_map(se_cmd); - return 0; + return; out_done: sc->scsi_done(sc); + return; +} + +/* + * ->queuecommand can be and usually is called from interrupt context, so + * defer the actual submission to a workqueue. + */ +static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc) +{ + 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, + sc->device->id, sc->device->channel, sc->device->lun, + sc->cmnd[0], scsi_bufflen(sc)); + + 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); + sc->scsi_done(sc); + return 0; + } + + tl_cmd->sc = sc; + INIT_WORK(&tl_cmd->work, tcm_loop_submission_work); + queue_work(tcm_loop_workqueue, &tl_cmd->work); return 0; } @@ -1458,7 +1463,11 @@ static void tcm_loop_deregister_configfs(void) static int __init tcm_loop_fabric_init(void) { - int ret; + int ret = -ENOMEM; + + tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0); + if (!tcm_loop_workqueue) + goto out; tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache", sizeof(struct tcm_loop_cmd), @@ -1467,20 +1476,27 @@ static int __init tcm_loop_fabric_init(void) if (!tcm_loop_cmd_cache) { pr_debug("kmem_cache_create() for" " tcm_loop_cmd_cache failed\n"); - return -ENOMEM; + goto out_destroy_workqueue; } ret = tcm_loop_alloc_core_bus(); if (ret) - return ret; + goto out_destroy_cache; ret = tcm_loop_register_configfs(); - if (ret) { - tcm_loop_release_core_bus(); - return ret; - } + if (ret) + goto out_release_core_bus; return 0; + +out_release_core_bus: + tcm_loop_release_core_bus(); +out_destroy_cache: + kmem_cache_destroy(tcm_loop_cmd_cache); +out_destroy_workqueue: + destroy_workqueue(tcm_loop_workqueue); +out: + return ret; } static void __exit tcm_loop_fabric_exit(void) @@ -1488,6 +1504,7 @@ static void __exit tcm_loop_fabric_exit(void) tcm_loop_deregister_configfs(); tcm_loop_release_core_bus(); kmem_cache_destroy(tcm_loop_cmd_cache); + destroy_workqueue(tcm_loop_workqueue); } MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module"); diff --git a/drivers/target/loopback/tcm_loop.h b/drivers/target/loopback/tcm_loop.h index 15a03644147..fc9bade9641 100644 --- a/drivers/target/loopback/tcm_loop.h +++ b/drivers/target/loopback/tcm_loop.h @@ -12,9 +12,9 @@ struct tcm_loop_cmd { u32 sc_cmd_state; /* Pointer to the CDB+Data descriptor from Linux/SCSI subsystem */ struct scsi_cmnd *sc; - struct list_head *tl_cmd_list; /* The TCM I/O descriptor that is accessed via container_of() */ struct se_cmd tl_se_cmd; + struct work_struct work; /* Sense buffer that will be mapped into outgoing status */ unsigned char tl_sense_buf[TRANSPORT_SENSE_BUFFER]; }; |