Here's the second iteration of http://marc.theaimsgroup.com/?l=linux-scsi&m=116136002113903&w=2 Changes since that version: - Restructure to put the callback in the scsi_host_template (thanks to James Smart for insisting). Now drivers can fill in scan_finished and call scsi_scan_host(). That takes care of doing their scans asynchronously. I should document the new role of scsi_scan_host(). James, relative to the one you've been looking at, this version adds the 'elapsed_jiffies' parameter back in (renamed to 'time'). qla2xxx and aic94xx needed it too, and it seemed rather intrusive to add an extra element to their host data structures when I can just keep it on the stack. diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig index 9540eb8..c312444 100644 --- a/drivers/scsi/Kconfig +++ b/drivers/scsi/Kconfig @@ -216,6 +216,23 @@ config SCSI_LOGGING there should be no noticeable performance impact as long as you have logging turned off. +config SCSI_SCAN_ASYNC + bool "Asynchronous SCSI scanning" + depends on SCSI + help + The SCSI subsystem can probe for devices while the rest of the + system continues booting, and even probe devices on different + busses in parallel, leading to a significant speed-up. + If you have built SCSI as modules, enabling this option can + be a problem as the devices may not have been found by the + time your system expects them to have been. You can load the + scsi_wait_scan module to ensure that all scans have completed. + If you build your SCSI drivers into the kernel, then everything + will work fine if you say Y here. + + You can override this choice by specifying scsi_mod.scan="sync" + or "async" on the kernel's command line. + menu "SCSI Transports" depends on SCSI diff --git a/drivers/scsi/aic94xx/aic94xx_init.c b/drivers/scsi/aic94xx/aic94xx_init.c index 99743ca..3c46005 100644 --- a/drivers/scsi/aic94xx/aic94xx_init.c +++ b/drivers/scsi/aic94xx/aic94xx_init.c @@ -57,6 +57,7 @@ MODULE_PARM_DESC(collector, "\n" char sas_addr_str[2*SAS_ADDR_SIZE + 1] = ""; static struct scsi_transport_template *aic94xx_transport_template; +static int asd_scan_finished(struct Scsi_Host *, unsigned long); static struct scsi_host_template aic94xx_sht = { .module = THIS_MODULE, @@ -66,6 +67,7 @@ static struct scsi_host_template aic94xx .target_alloc = sas_target_alloc, .slave_configure = sas_slave_configure, .slave_destroy = sas_slave_destroy, + .scan_finished = asd_scan_finished, .change_queue_depth = sas_change_queue_depth, .change_queue_type = sas_change_queue_type, .bios_param = sas_bios_param, @@ -546,6 +548,18 @@ static int asd_unregister_sas_ha(struct return err; } +static int asd_scan_finished(struct Scsi_Host *shost, unsigned long time) +{ + /* give the phy enabling interrupt event time to come in (1s + * is empirically about all it takes) */ + if (time < HZ) + return 0; + + /* Wait for discovery to finish */ + scsi_flush_work(shost); + return 1; +} + static int __devinit asd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) { @@ -677,11 +691,8 @@ static int __devinit asd_pci_probe(struc goto Err_en_phys; } ASD_DPRINTK("enabled phys\n"); - /* give the phy enabling interrupt event time to come in (1s - * is empirically about all it takes) */ - ssleep(1); - /* Wait for discovery to finish */ - scsi_flush_work(asd_ha->sas_ha.core.shost); + + scsi_scan_host(shost); return 0; Err_en_phys: diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c index a5723ad..3ad31df 100644 --- a/drivers/scsi/lpfc/lpfc_init.c +++ b/drivers/scsi/lpfc/lpfc_init.c @@ -416,33 +416,6 @@ lpfc_config_port_post(struct lpfc_hba * return (0); } -static int -lpfc_discovery_wait(struct lpfc_hba *phba) -{ - int i = 0; - - while ((phba->hba_state != LPFC_HBA_READY) || - (phba->num_disc_nodes) || (phba->fc_prli_sent) || - ((phba->fc_map_cnt == 0) && (i<2)) || - (phba->sli.sli_flag & LPFC_SLI_MBOX_ACTIVE)) { - /* Check every second for 30 retries. */ - i++; - if (i > 30) { - return -ETIMEDOUT; - } - if ((i >= 15) && (phba->hba_state <= LPFC_LINK_DOWN)) { - /* The link is down. Set linkdown timeout */ - return -ETIMEDOUT; - } - - /* Delay for 1 second to give discovery time to complete. */ - msleep(1000); - - } - - return 0; -} - /************************************************************************/ /* */ /* lpfc_hba_down_prep */ @@ -1441,7 +1414,6 @@ lpfc_scsi_free(struct lpfc_hba * phba) return 0; } - static int __devinit lpfc_pci_probe_one(struct pci_dev *pdev, const struct pci_device_id *pid) { @@ -1647,6 +1619,7 @@ lpfc_pci_probe_one(struct pci_dev *pdev, if (error) goto out_kthread_stop; + scsi_scan_host(host); error = lpfc_alloc_sysfs_attr(phba); if (error) goto out_remove_host; @@ -1677,8 +1650,6 @@ lpfc_pci_probe_one(struct pci_dev *pdev, */ host->can_queue = phba->cfg_hba_queue_depth - 10; - lpfc_discovery_wait(phba); - if (phba->cfg_poll & DISABLE_FCP_RING_INT) { spin_lock_irq(phba->host->host_lock); lpfc_poll_start_timer(phba); diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c index 97ae98d..60623f1 100644 --- a/drivers/scsi/lpfc/lpfc_scsi.c +++ b/drivers/scsi/lpfc/lpfc_scsi.c @@ -1267,6 +1267,29 @@ lpfc_slave_destroy(struct scsi_device *s return; } +static int lpfc_scan_finished(struct Scsi_Host *shost, unsigned long time) +{ + struct lpfc_hba *phba = (struct lpfc_hba *)shost->hostdata; + + if (!phba->host) + return 1; + if (time >= 30 * HZ) + return 1; + + if (phba->hba_state != LPFC_HBA_READY) + return 0; + if (phba->num_disc_nodes || phba->fc_prli_sent) + return 0; + if ((phba->fc_map_cnt == 0) && (time < 2 * HZ)) + return 0; + if (phba->sli.sli_flag & LPFC_SLI_MBOX_ACTIVE) + return 0; + if ((phba->hba_state > LPFC_LINK_DOWN) || (time < 15 * HZ)) + return 0; + + return 1; +} + struct scsi_host_template lpfc_template = { .module = THIS_MODULE, .name = LPFC_DRIVER_NAME, @@ -1278,6 +1301,7 @@ struct scsi_host_template lpfc_template .slave_alloc = lpfc_slave_alloc, .slave_configure = lpfc_slave_configure, .slave_destroy = lpfc_slave_destroy, + .scan_finished = lpfc_scan_finished, .this_id = -1, .sg_tablesize = LPFC_SG_SEG_CNT, .cmd_per_lun = LPFC_CMD_PER_LUN, diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c index 3f20d76..91b8bf3 100644 --- a/drivers/scsi/qla2xxx/qla_os.c +++ b/drivers/scsi/qla2xxx/qla_os.c @@ -83,6 +83,7 @@ MODULE_PARM_DESC(ql2xfdmienable, static int qla2xxx_slave_configure(struct scsi_device * device); static int qla2xxx_slave_alloc(struct scsi_device *); static void qla2xxx_slave_destroy(struct scsi_device *); +static int qla2xxx_scan_finished(struct Scsi_Host *); static int qla2x00_queuecommand(struct scsi_cmnd *cmd, void (*fn)(struct scsi_cmnd *)); static int qla24xx_queuecommand(struct scsi_cmnd *cmd, @@ -111,6 +112,7 @@ static struct scsi_host_template qla2x00 .slave_alloc = qla2xxx_slave_alloc, .slave_destroy = qla2xxx_slave_destroy, + .scan_finished = qla2x00_scan_finished, .change_queue_depth = qla2x00_change_queue_depth, .change_queue_type = qla2x00_change_queue_type, .this_id = -1, @@ -1353,6 +1355,20 @@ qla24xx_disable_intrs(scsi_qla_host_t *h spin_unlock_irqrestore(&ha->hardware_lock, flags); } +static int qla2x00_scan_finished(struct Scsi_Host *shost, unsigned long time) +{ + scsi_qla_host_t *ha = (scsi_qla_host_t *)shost->hostdata; + + if (time > ha->loop_reset_delay * HZ) + return 1; + + qla2x00_check_fabric_devices(ha); + + if (ha->device_flags & (DFLG_NO_CABLE | DFLG_FABRIC_DEVICES)) + return 1; + return !(ha->device_flags & SWITCH_FOUND); +} + /* * PCI driver interface */ @@ -1363,8 +1379,7 @@ qla2x00_probe_one(struct pci_dev *pdev, device_reg_t __iomem *reg; struct Scsi_Host *host; scsi_qla_host_t *ha; - unsigned long flags = 0; - unsigned long wait_switch = 0; + unsigned long flags; char pci_info[20]; char fw_str[30]; fc_port_t *fcport; @@ -1614,22 +1629,6 @@ qla2x00_probe_one(struct pci_dev *pdev, ha->isp_ops.enable_intrs(ha); - /* v2.19.5b6 */ - /* - * Wait around max loop_reset_delay secs for the devices to come - * on-line. We don't want Linux scanning before we are ready. - * - */ - for (wait_switch = jiffies + (ha->loop_reset_delay * HZ); - time_before(jiffies,wait_switch) && - !(ha->device_flags & (DFLG_NO_CABLE | DFLG_FABRIC_DEVICES)) - && (ha->device_flags & SWITCH_FOUND) ;) { - - qla2x00_check_fabric_devices(ha); - - msleep(10); - } - pci_set_drvdata(pdev, ha); ha->flags.init_done = 1; num_hosts++; @@ -1637,6 +1636,7 @@ qla2x00_probe_one(struct pci_dev *pdev, ret = scsi_add_host(host, &pdev->dev); if (ret) goto probe_failed; + scsi_scan_host(host); qla2x00_alloc_sysfs_attr(ha); diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 148e24c..bbeddf9 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -89,7 +89,13 @@ module_param_named(max_luns, max_scsi_lu MODULE_PARM_DESC(max_luns, "last scsi LUN (should be between 1 and 2^32-1)"); -static char scsi_scan_type[6] = "sync"; +#ifdef CONFIG_SCSI_SCAN_ASYNC +#define SCSI_SCAN_TYPE_DEFAULT "async" +#else +#define SCSI_SCAN_TYPE_DEFAULT "sync" +#endif + +static char scsi_scan_type[6] = SCSI_SCAN_TYPE_DEFAULT; module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO); MODULE_PARM_DESC(scan, "sync, async or none"); @@ -1533,6 +1539,9 @@ void scsi_scan_target(struct device *par { struct Scsi_Host *shost = dev_to_shost(parent); + if (strncmp(scsi_scan_type, "none", 4) == 0) + return; + if (!shost->async_scan) scsi_complete_async_scans(); @@ -1623,7 +1632,7 @@ static void scsi_sysfs_add_devices(struc * that other asynchronous scans started after this one won't affect the * ordering of the discovered devices. */ -struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) +static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) { struct async_scan_data *data; @@ -1667,7 +1676,7 @@ struct async_scan_data *scsi_prep_async_ * This function announces all the devices it has found to the rest * of the system. */ -void scsi_finish_async_scan(struct async_scan_data *data) +static void scsi_finish_async_scan(struct async_scan_data *data) { struct Scsi_Host *shost; @@ -1700,12 +1709,22 @@ void scsi_finish_async_scan(struct async kfree(data); } -static int do_scan_async(void *_data) +static void do_scsi_scan_host(struct Scsi_Host *shost) { - struct async_scan_data *data = _data; - scsi_scan_host_selected(data->shost, SCAN_WILD_CARD, SCAN_WILD_CARD, + if (shost->hostt->scan_finished) { + unsigned long start = jiffies; + while (!shost->hostt->scan_finished(shost, jiffies - start)) + msleep(10); + } else { + scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD, SCAN_WILD_CARD, 0); + } +} +static int do_scan_async(void *_data) +{ + struct async_scan_data *data = _data; + do_scsi_scan_host(data->shost); scsi_finish_async_scan(data); return 0; } @@ -1723,10 +1742,10 @@ void scsi_scan_host(struct Scsi_Host *sh data = scsi_prep_async_scan(shost); if (!data) { - scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD, - SCAN_WILD_CARD, 0); + do_scsi_scan_host(shost); return; } + kthread_run(do_scan_async, data, "scsi_scan_%d", shost->host_no); } EXPORT_SYMBOL(scsi_scan_host); diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index ba5b3eb..359672a 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -241,6 +241,17 @@ #endif void (* target_destroy)(struct scsi_target *); /* + * If a host has the ability to discover targets on its own instead + * of scanning the entire bus, it can fill in this function and + * call scsi_scan_host(). This function will be called periodically + * until it returns 1 with the scsi_host and the elapsed time of + * the scan in jiffies. + * + * Status: OPTIONAL + */ + int (* scan_finished)(struct Scsi_Host *, unsigned long); + + /* * fill in this function to allow the queue depth of this host * to be changeable (on a per device basis). returns either * the current queue depth setting (may be different from what - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
