diff options
Diffstat (limited to 'drivers/s390/cio/device_fsm.c')
| -rw-r--r-- | drivers/s390/cio/device_fsm.c | 1250 |
1 files changed, 1250 insertions, 0 deletions
diff --git a/drivers/s390/cio/device_fsm.c b/drivers/s390/cio/device_fsm.c new file mode 100644 index 000000000000..9b7f6f548b1d --- /dev/null +++ b/drivers/s390/cio/device_fsm.c @@ -0,0 +1,1250 @@ +/* + * drivers/s390/cio/device_fsm.c + * finite state machine for device handling + * + * Copyright (C) 2002 IBM Deutschland Entwicklung GmbH, + * IBM Corporation + * Author(s): Cornelia Huck(cohuck@de.ibm.com) + * Martin Schwidefsky (schwidefsky@de.ibm.com) + */ + +#include <linux/module.h> +#include <linux/config.h> +#include <linux/init.h> + +#include <asm/ccwdev.h> +#include <asm/qdio.h> + +#include "cio.h" +#include "cio_debug.h" +#include "css.h" +#include "device.h" +#include "chsc.h" +#include "ioasm.h" +#include "qdio.h" + +int +device_is_online(struct subchannel *sch) +{ + struct ccw_device *cdev; + + if (!sch->dev.driver_data) + return 0; + cdev = sch->dev.driver_data; + return (cdev->private->state == DEV_STATE_ONLINE); +} + +int +device_is_disconnected(struct subchannel *sch) +{ + struct ccw_device *cdev; + + if (!sch->dev.driver_data) + return 0; + cdev = sch->dev.driver_data; + return (cdev->private->state == DEV_STATE_DISCONNECTED || + cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID); +} + +void +device_set_disconnected(struct subchannel *sch) +{ + struct ccw_device *cdev; + + if (!sch->dev.driver_data) + return; + cdev = sch->dev.driver_data; + ccw_device_set_timeout(cdev, 0); + cdev->private->flags.fake_irb = 0; + cdev->private->state = DEV_STATE_DISCONNECTED; +} + +void +device_set_waiting(struct subchannel *sch) +{ + struct ccw_device *cdev; + + if (!sch->dev.driver_data) + return; + cdev = sch->dev.driver_data; + ccw_device_set_timeout(cdev, 10*HZ); + cdev->private->state = DEV_STATE_WAIT4IO; +} + +/* + * Timeout function. It just triggers a DEV_EVENT_TIMEOUT. + */ +static void +ccw_device_timeout(unsigned long data) +{ + struct ccw_device *cdev; + + cdev = (struct ccw_device *) data; + spin_lock_irq(cdev->ccwlock); + dev_fsm_event(cdev, DEV_EVENT_TIMEOUT); + spin_unlock_irq(cdev->ccwlock); +} + +/* + * Set timeout + */ +void +ccw_device_set_timeout(struct ccw_device *cdev, int expires) +{ + if (expires == 0) { + del_timer(&cdev->private->timer); + return; + } + if (timer_pending(&cdev->private->timer)) { + if (mod_timer(&cdev->private->timer, jiffies + expires)) + return; + } + cdev->private->timer.function = ccw_device_timeout; + cdev->private->timer.data = (unsigned long) cdev; + cdev->private->timer.expires = jiffies + expires; + add_timer(&cdev->private->timer); +} + +/* Kill any pending timers after machine check. */ +void +device_kill_pending_timer(struct subchannel *sch) +{ + struct ccw_device *cdev; + + if (!sch->dev.driver_data) + return; + cdev = sch->dev.driver_data; + ccw_device_set_timeout(cdev, 0); +} + +/* + * Cancel running i/o. This is called repeatedly since halt/clear are + * asynchronous operations. We do one try with cio_cancel, two tries + * with cio_halt, 255 tries with cio_clear. If everythings fails panic. + * Returns 0 if device now idle, -ENODEV for device not operational and + * -EBUSY if an interrupt is expected (either from halt/clear or from a + * status pending). + */ +int +ccw_device_cancel_halt_clear(struct ccw_device *cdev) +{ + struct subchannel *sch; + int ret; + + sch = to_subchannel(cdev->dev.parent); + ret = stsch(sch->irq, &sch->schib); + if (ret || !sch->schib.pmcw.dnv) + return -ENODEV; + if (!sch->schib.pmcw.ena || sch->schib.scsw.actl == 0) + /* Not operational or no activity -> done. */ + return 0; + /* Stage 1: cancel io. */ + if (!(sch->schib.scsw.actl & SCSW_ACTL_HALT_PEND) && + !(sch->schib.scsw.actl & SCSW_ACTL_CLEAR_PEND)) { + ret = cio_cancel(sch); + if (ret != -EINVAL) + return ret; + /* cancel io unsuccessful. From now on it is asynchronous. */ + cdev->private->iretry = 3; /* 3 halt retries. */ + } + if (!(sch->schib.scsw.actl & SCSW_ACTL_CLEAR_PEND)) { + /* Stage 2: halt io. */ + if (cdev->private->iretry) { + cdev->private->iretry--; + ret = cio_halt(sch); + return (ret == 0) ? -EBUSY : ret; + } + /* halt io unsuccessful. */ + cdev->private->iretry = 255; /* 255 clear retries. */ + } + /* Stage 3: clear io. */ + if (cdev->private->iretry) { + cdev->private->iretry--; + ret = cio_clear (sch); + return (ret == 0) ? -EBUSY : ret; + } + panic("Can't stop i/o on subchannel.\n"); +} + +static int +ccw_device_handle_oper(struct ccw_device *cdev) +{ + struct subchannel *sch; + + sch = to_subchannel(cdev->dev.parent); + cdev->private->flags.recog_done = 1; + /* + * Check if cu type and device type still match. If + * not, it is certainly another device and we have to + * de- and re-register. Also check here for non-matching devno. + */ + if (cdev->id.cu_type != cdev->private->senseid.cu_type || + cdev->id.cu_model != cdev->private->senseid.cu_model || + cdev->id.dev_type != cdev->private->senseid.dev_type || + cdev->id.dev_model != cdev->private->senseid.dev_model || + cdev->private->devno != sch->schib.pmcw.dev) { + PREPARE_WORK(&cdev->private->kick_work, + ccw_device_do_unreg_rereg, (void *)cdev); + queue_work(ccw_device_work, &cdev->private->kick_work); + return 0; + } + cdev->private->flags.donotify = 1; + return 1; +} + +/* + * The machine won't give us any notification by machine check if a chpid has + * been varied online on the SE so we have to find out by magic (i. e. driving + * the channel subsystem to device selection and updating our path masks). + */ +static inline void +__recover_lost_chpids(struct subchannel *sch, int old_lpm) +{ + int mask, i; + + for (i = 0; i<8; i++) { + mask = 0x80 >> i; + if (!(sch->lpm & mask)) + continue; + if (old_lpm & mask) + continue; + chpid_is_actually_online(sch->schib.pmcw.chpid[i]); + } +} + +/* + * Stop device recognition. + */ +static void +ccw_device_recog_done(struct ccw_device *cdev, int state) +{ + struct subchannel *sch; + int notify, old_lpm, same_dev; + + sch = to_subchannel(cdev->dev.parent); + + ccw_device_set_timeout(cdev, 0); + cio_disable_subchannel(sch); + /* + * Now that we tried recognition, we have performed device selection + * through ssch() and the path information is up to date. + */ + old_lpm = sch->lpm; + stsch(sch->irq, &sch->schib); + sch->lpm = sch->schib.pmcw.pim & + sch->schib.pmcw.pam & + sch->schib.pmcw.pom & + sch->opm; + if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID) + /* Force reprobe on all chpids. */ + old_lpm = 0; + if (sch->lpm != old_lpm) + __recover_lost_chpids(sch, old_lpm); + if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID) { + if (state == DEV_STATE_NOT_OPER) { + cdev->private->flags.recog_done = 1; + cdev->private->state = DEV_STATE_DISCONNECTED; + return; + } + /* Boxed devices don't need extra treatment. */ + } + notify = 0; + same_dev = 0; /* Keep the compiler quiet... */ + switch (state) { + case DEV_STATE_NOT_OPER: + CIO_DEBUG(KERN_WARNING, 2, + "SenseID : unknown device %04x on subchannel %04x\n", + cdev->private->devno, sch->irq); + break; + case DEV_STATE_OFFLINE: + if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID) { + same_dev = ccw_device_handle_oper(cdev); + notify = 1; + } + /* fill out sense information */ + cdev->id = (struct ccw_device_id) { + .cu_type = cdev->private->senseid.cu_type, + .cu_model = cdev->private->senseid.cu_model, + .dev_type = cdev->private->senseid.dev_type, + .dev_model = cdev->private->senseid.dev_model, + }; + if (notify) { + cdev->private->state = DEV_STATE_OFFLINE; + if (same_dev) { + /* Get device online again. */ + ccw_device_online(cdev); + wake_up(&cdev->private->wait_q); + } + return; + } + /* Issue device info message. */ + CIO_DEBUG(KERN_INFO, 2, "SenseID : device %04x reports: " + "CU Type/Mod = %04X/%02X, Dev Type/Mod = " + "%04X/%02X\n", cdev->private->devno, + cdev->id.cu_type, cdev->id.cu_model, + cdev->id.dev_type, cdev->id.dev_model); + break; + case DEV_STATE_BOXED: + CIO_DEBUG(KERN_WARNING, 2, + "SenseID : boxed device %04x on subchannel %04x\n", + cdev->private->devno, sch->irq); + break; + } + cdev->private->state = state; + io_subchannel_recog_done(cdev); + if (state != DEV_STATE_NOT_OPER) + wake_up(&cdev->private->wait_q); +} + +/* + * Function called from device_id.c after sense id has completed. + */ +void +ccw_device_sense_id_done(struct ccw_device *cdev, int err) +{ + switch (err) { + case 0: + ccw_device_recog_done(cdev, DEV_STATE_OFFLINE); + break; + case -ETIME: /* Sense id stopped by timeout. */ + ccw_device_recog_done(cdev, DEV_STATE_BOXED); + break; + default: + ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER); + break; + } +} + +static void +ccw_device_oper_notify(void *data) +{ + struct ccw_device *cdev; + struct subchannel *sch; + int ret; + + cdev = (struct ccw_device *)data; + sch = to_subchannel(cdev->dev.parent); + ret = (sch->driver && sch->driver->notify) ? + sch->driver->notify(&sch->dev, CIO_OPER) : 0; + if (!ret) + /* Driver doesn't want device back. */ + ccw_device_do_unreg_rereg((void *)cdev); + else + wake_up(&cdev->private->wait_q); +} + +/* + * Finished with online/offline processing. + */ +static void +ccw_device_done(struct ccw_device *cdev, int state) +{ + struct subchannel *sch; + + sch = to_subchannel(cdev->dev.parent); + + if (state != DEV_STATE_ONLINE) + cio_disable_subchannel(sch); + + /* Reset device status. */ + memset(&cdev->private->irb, 0, sizeof(struct irb)); + + cdev->private->state = state; + + + if (state == DEV_STATE_BOXED) + CIO_DEBUG(KERN_WARNING, 2, + "Boxed device %04x on subchannel %04x\n", + cdev->private->devno, sch->irq); + + if (cdev->private->flags.donotify) { + cdev->private->flags.donotify = 0; + PREPARE_WORK(&cdev->private->kick_work, ccw_device_oper_notify, + (void *)cdev); + queue_work(ccw_device_notify_work, &cdev->private->kick_work); + } + wake_up(&cdev->private->wait_q); + + if (css_init_done && state != DEV_STATE_ONLINE) + put_device (&cdev->dev); +} + +/* + * Function called from device_pgid.c after sense path ground has completed. + */ +void +ccw_device_sense_pgid_done(struct ccw_device *cdev, int err) +{ + struct subchannel *sch; + + sch = to_subchannel(cdev->dev.parent); + switch (err) { + case 0: + /* Start Path Group verification. */ + sch->vpm = 0; /* Start with no path groups set. */ + cdev->private->state = DEV_STATE_VERIFY; + ccw_device_verify_start(cdev); + break; + case -ETIME: /* Sense path group id stopped by timeout. */ + case -EUSERS: /* device is reserved for someone else. */ + ccw_device_done(cdev, DEV_STATE_BOXED); + break; + case -EOPNOTSUPP: /* path grouping not supported, just set online. */ + cdev->private->options.pgroup = 0; + ccw_device_done(cdev, DEV_STATE_ONLINE); + break; + default: + ccw_device_done(cdev, DEV_STATE_NOT_OPER); + break; + } +} + +/* + * Start device recognition. + */ +int +ccw_device_recognition(struct ccw_device *cdev) +{ + struct subchannel *sch; + int ret; + + if ((cdev->private->state != DEV_STATE_NOT_OPER) && + (cdev->private->state != DEV_STATE_BOXED)) + return -EINVAL; + sch = to_subchannel(cdev->dev.parent); + ret = cio_enable_subchannel(sch, sch->schib.pmcw.isc); + if (ret != 0) + /* Couldn't enable the subchannel for i/o. Sick device. */ + return ret; + + /* After 60s the device recognition is considered to have failed. */ + ccw_device_set_timeout(cdev, 60*HZ); + + /* + * We used to start here with a sense pgid to find out whether a device + * is locked by someone else. Unfortunately, the sense pgid command + * code has other meanings on devices predating the path grouping + * algorithm, so we start with sense id and box the device after an + * timeout (or if sense pgid during path verification detects the device + * is locked, as may happen on newer devices). + */ + cdev->private->flags.recog_done = 0; + cdev->private->state = DEV_STATE_SENSE_ID; + ccw_device_sense_id_start(cdev); + return 0; +} + +/* + * Handle timeout in device recognition. + */ +static void +ccw_device_recog_timeout(struct ccw_device *cdev, enum dev_event dev_event) +{ + int ret; + + ret = ccw_device_cancel_halt_clear(cdev); + switch (ret) { + case 0: + ccw_device_recog_done(cdev, DEV_STATE_BOXED); + break; + case -ENODEV: + ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER); + break; + default: + ccw_device_set_timeout(cdev, 3*HZ); + } +} + + +static void +ccw_device_nopath_notify(void *data) +{ + struct ccw_device *cdev; + struct subchannel *sch; + int ret; + + cdev = (struct ccw_device *)data; + sch = to_subchannel(cdev->dev.parent); + /* Extra sanity. */ + if (sch->lpm) + return; + ret = (sch->driver && sch->driver->notify) ? + sch->driver->notify(&sch->dev, CIO_NO_PATH) : 0; + if (!ret) { + if (get_device(&sch->dev)) { + /* Driver doesn't want to keep device. */ + cio_disable_subchannel(sch); + if (get_device(&cdev->dev)) { + PREPARE_WORK(&cdev->private->kick_work, + ccw_device_call_sch_unregister, + (void *)cdev); + queue_work(ccw_device_work, + &cdev->private->kick_work); + } else + put_device(&sch->dev); + } + } else { + cio_disable_subchannel(sch); + ccw_device_set_timeout(cdev, 0); + cdev->private->flags.fake_irb = 0; + cdev->private->state = DEV_STATE_DISCONNECTED; + wake_up(&cdev->private->wait_q); + } +} + +void +ccw_device_verify_done(struct ccw_device *cdev, int err) +{ + cdev->private->flags.doverify = 0; + switch (err) { + case -EOPNOTSUPP: /* path grouping not supported, just set online. */ + cdev->private->options.pgroup = 0; + case 0: + ccw_device_done(cdev, DEV_STATE_ONLINE); + /* Deliver fake irb to device driver, if needed. */ + if (cdev->private->flags.fake_irb) { + memset(&cdev->private->irb, 0, sizeof(struct irb)); + cdev->private->irb.scsw = (struct scsw) { + .cc = 1, + .fctl = SCSW_FCTL_START_FUNC, + .actl = SCSW_ACTL_START_PEND, + .stctl = SCSW_STCTL_STATUS_PEND, + }; + cdev->private->flags.fake_irb = 0; + if (cdev->handler) + cdev->handler(cdev, cdev->private->intparm, + &cdev->private->irb); + memset(&cdev->private->irb, 0, sizeof(struct irb)); + } + break; + case -ETIME: + ccw_device_done(cdev, DEV_STATE_BOXED); + break; + default: + PREPARE_WORK(&cdev->private->kick_work, + ccw_device_nopath_notify, (void *)cdev); + queue_work(ccw_device_notify_work, &cdev->private->kick_work); + ccw_device_done(cdev, DEV_STATE_NOT_OPER); + break; + } +} + +/* + * Get device online. + */ +int +ccw_device_online(struct ccw_device *cdev) +{ + struct subchannel *sch; + int ret; + + if ((cdev->private->state != DEV_STATE_OFFLINE) && + (cdev->private->state != DEV_STATE_BOXED)) + return -EINVAL; + sch = to_subchannel(cdev->dev.parent); + if (css_init_done && !get_device(&cdev->dev)) + return -ENODEV; + ret = cio_enable_subchannel(sch, sch->schib.pmcw.isc); + if (ret != 0) { + /* Couldn't enable the subchannel for i/o. Sick device. */ + if (ret == -ENODEV) + dev_fsm_event(cdev, DEV_EVENT_NOTOPER); + return ret; + } + /* Do we want to do path grouping? */ + if (!cdev->private->options.pgroup) { + /* No, set state online immediately. */ + ccw_device_done(cdev, DEV_STATE_ONLINE); + return 0; + } + /* Do a SensePGID first. */ + cdev->private->state = DEV_STATE_SENSE_PGID; + ccw_device_sense_pgid_start(cdev); + return 0; +} + +void +ccw_device_disband_done(struct ccw_device *cdev, int err) +{ + switch (err) { + case 0: + ccw_device_done(cdev, DEV_STATE_OFFLINE); + break; + case -ETIME: + ccw_device_done(cdev, DEV_STATE_BOXED); + break; + default: + ccw_device_done(cdev, DEV_STATE_NOT_OPER); + break; + } +} + +/* + * Shutdown device. + */ +int +ccw_device_offline(struct ccw_device *cdev) +{ + struct subchannel *sch; + + sch = to_subchannel(cdev->dev.parent); + if (stsch(sch->irq, &sch->schib) || !sch->schib.pmcw.dnv) + return -ENODEV; + if (cdev->private->state != DEV_STATE_ONLINE) { + if (sch->schib.scsw.actl != 0) + return -EBUSY; + return -EINVAL; + } + if (sch->schib.scsw.actl != 0) + return -EBUSY; + /* Are we doing path grouping? */ + if (!cdev->private->options.pgroup) { + /* No, set state offline immediately. */ + ccw_device_done(cdev, DEV_STATE_OFFLINE); + return 0; + } + /* Start Set Path Group commands. */ + cdev->private->state = DEV_STATE_DISBAND_PGID; + ccw_device_disband_start(cdev); + return 0; +} + +/* + * Handle timeout in device online/offline process. + */ +static void +ccw_device_onoff_timeout(struct ccw_device *cdev, enum dev_event dev_event) +{ + int ret; + + ret = ccw_device_cancel_halt_clear(cdev); + switch (ret) { + case 0: + ccw_device_done(cdev, DEV_STATE_BOXED); + break; + case -ENODEV: + ccw_device_done(cdev, DEV_STATE_NOT_OPER); + break; + default: + ccw_device_set_timeout(cdev, 3*HZ); + } +} + +/* + * Handle not oper event in device recognition. + */ +static void +ccw_device_recog_notoper(struct ccw_device *cdev, enum dev_event dev_event) +{ + ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER); +} + +/* + * Handle not operational event while offline. + */ +static void +ccw_device_offline_notoper(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct subchannel *sch; + + cdev->private->state = DEV_STATE_NOT_OPER; + sch = to_subchannel(cdev->dev.parent); + if (get_device(&cdev->dev)) { + PREPARE_WORK(&cdev->private->kick_work, + ccw_device_call_sch_unregister, (void *)cdev); + queue_work(ccw_device_work, &cdev->private->kick_work); + } + wake_up(&cdev->private->wait_q); +} + +/* + * Handle not operational event while online. + */ +static void +ccw_device_online_notoper(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct subchannel *sch; + + sch = to_subchannel(cdev->dev.parent); + if (sch->driver->notify && + sch->driver->notify(&sch->dev, sch->lpm ? CIO_GONE : CIO_NO_PATH)) { + ccw_device_set_timeout(cdev, 0); + cdev->private->flags.fake_irb = 0; + cdev->private->state = DEV_STATE_DISCONNECTED; + wake_up(&cdev->private->wait_q); + return; + } + cdev->private->state = DEV_STATE_NOT_OPER; + cio_disable_subchannel(sch); + if (sch->schib.scsw.actl != 0) { + // FIXME: not-oper indication to device driver ? + ccw_device_call_handler(cdev); + } + if (get_device(&cdev->dev)) { + PREPARE_WORK(&cdev->private->kick_work, + ccw_device_call_sch_unregister, (void *)cdev); + queue_work(ccw_device_work, &cdev->private->kick_work); + } + wake_up(&cdev->private->wait_q); +} + +/* + * Handle path verification event. + */ +static void +ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct subchannel *sch; + + if (!cdev->private->options.pgroup) + return; + if (cdev->private->state == DEV_STATE_W4SENSE) { + cdev->private->flags.doverify = 1; + return; + } + sch = to_subchannel(cdev->dev.parent); + /* + * Since we might not just be coming from an interrupt from the + * subchannel we have to update the schib. + */ + stsch(sch->irq, &sch->schib); + + if (sch->schib.scsw.actl != 0 || + (cdev->private->irb.scsw.stctl & SCSW_STCTL_STATUS_PEND)) { + /* + * No final status yet or final status not yet delivered + * to the device driver. Can't do path verfication now, + * delay until final status was delivered. + */ + cdev->private->flags.doverify = 1; + return; + } + /* Device is idle, we can do the path verification. */ + cdev->private->state = DEV_STATE_VERIFY; + ccw_device_verify_start(cdev); +} + +/* + * Got an interrupt for a normal io (state online). + */ +static void +ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct irb *irb; + + irb = (struct irb *) __LC_IRB; + /* Check for unsolicited interrupt. */ + if ((irb->scsw.stctl == + (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) + && (!irb->scsw.cc)) { + if ((irb->scsw.dstat & DEV_STAT_UNIT_CHECK) && + !irb->esw.esw0.erw.cons) { + /* Unit check but no sense data. Need basic sense. */ + if (ccw_device_do_sense(cdev, irb) != 0) + goto call_handler_unsol; + memcpy(irb, &cdev->private->irb, sizeof(struct irb)); + cdev->private->state = DEV_STATE_W4SENSE; + cdev->private->intparm = 0; + return; + } +call_handler_unsol: + if (cdev->handler) + cdev->handler (cdev, 0, irb); + return; + } + /* Accumulate status and find out if a basic sense is needed. */ + ccw_device_accumulate_irb(cdev, irb); + if (cdev->private->flags.dosense) { + if (ccw_device_do_sense(cdev, irb) == 0) { + cdev->private->state = DEV_STATE_W4SENSE; + } + return; + } + /* Call the handler. */ + if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify) + /* Start delayed path verification. */ + ccw_device_online_verify(cdev, 0); +} + +/* + * Got an timeout in online state. + */ +static void +ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event) +{ + int ret; + + ccw_device_set_timeout(cdev, 0); + ret = ccw_device_cancel_halt_clear(cdev); + if (ret == -EBUSY) { + ccw_device_set_timeout(cdev, 3*HZ); + cdev->private->state = DEV_STATE_TIMEOUT_KILL; + return; + } + if (ret == -ENODEV) { + struct subchannel *sch; + + sch = to_subchannel(cdev->dev.parent); + if (!sch->lpm) { + PREPARE_WORK(&cdev->private->kick_work, + ccw_device_nopath_notify, (void *)cdev); + queue_work(ccw_device_notify_work, + &cdev->private->kick_work); + } else + dev_fsm_event(cdev, DEV_EVENT_NOTOPER); + } else if (cdev->handler) + cdev->handler(cdev, cdev->private->intparm, + ERR_PTR(-ETIMEDOUT)); +} + +/* + * Got an interrupt for a basic sense. + */ +void +ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct irb *irb; + + irb = (struct irb *) __LC_IRB; + /* Check for unsolicited interrupt. */ + if (irb->scsw.stctl == + (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) { + if (irb->scsw.cc == 1) + /* Basic sense hasn't started. Try again. */ + ccw_device_do_sense(cdev, irb); + else { + printk("Huh? %s(%s): unsolicited interrupt...\n", + __FUNCTION__, cdev->dev.bus_id); + if (cdev->handler) + cdev->handler (cdev, 0, irb); + } + return; + } + /* Add basic sense info to irb. */ + ccw_device_accumulate_basic_sense(cdev, irb); + if (cdev->private->flags.dosense) { + /* Another basic sense is needed. */ + ccw_device_do_sense(cdev, irb); + return; + } + cdev->private->state = DEV_STATE_ONLINE; + /* Call the handler. */ + if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify) + /* Start delayed path verification. */ + ccw_device_online_verify(cdev, 0); +} + +static void +ccw_device_clear_verify(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct irb *irb; + + irb = (struct irb *) __LC_IRB; + /* Accumulate status. We don't do basic sense. */ + ccw_device_accumulate_irb(cdev, irb); + /* Try to start delayed device verification. */ + ccw_device_online_verify(cdev, 0); + /* Note: Don't call handler for cio initiated clear! */ +} + +static void +ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct subchannel *sch; + + sch = to_subchannel(cdev->dev.parent); + ccw_device_set_timeout(cdev, 0); + /* OK, i/o is dead now. Call interrupt handler. */ + cdev->private->state = DEV_STATE_ONLINE; + if (cdev->handler) + cdev->handler(cdev, cdev->private->intparm, + ERR_PTR(-ETIMEDOUT)); + if (!sch->lpm) { + PREPARE_WORK(&cdev->private->kick_work, + ccw_device_nopath_notify, (void *)cdev); + queue_work(ccw_device_notify_work, &cdev->private->kick_work); + } else if (cdev->private->flags.doverify) + /* Start delayed path verification. */ + ccw_device_online_verify(cdev, 0); +} + +static void +ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event) +{ + int ret; + + ret = ccw_device_cancel_halt_clear(cdev); + if (ret == -EBUSY) { + ccw_device_set_timeout(cdev, 3*HZ); + return; + } + if (ret == -ENODEV) { + struct subchannel *sch; + + sch = to_subchannel(cdev->dev.parent); + if (!sch->lpm) { + PREPARE_WORK(&cdev->private->kick_work, + ccw_device_nopath_notify, (void *)cdev); + queue_work(ccw_device_notify_work, + &cdev->private->kick_work); + } else + dev_fsm_event(cdev, DEV_EVENT_NOTOPER); + return; + } + //FIXME: Can we get here? + cdev->private->state = DEV_STATE_ONLINE; + if (cdev->handler) + cdev->handler(cdev, cdev->private->intparm, + ERR_PTR(-ETIMEDOUT)); +} + +static void +ccw_device_wait4io_irq(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct irb *irb; + struct subchannel *sch; + + irb = (struct irb *) __LC_IRB; + /* + * Accumulate status and find out if a basic sense is needed. + * This is fine since we have already adapted the lpm. + */ + ccw_device_accumulate_irb(cdev, irb); + if (cdev->private->flags.dosense) { + if (ccw_device_do_sense(cdev, irb) == 0) { + cdev->private->state = DEV_STATE_W4SENSE; + } + return; + } + + /* Iff device is idle, reset timeout. */ + sch = to_subchannel(cdev->dev.parent); + if (!stsch(sch->irq, &sch->schib)) + if (sch->schib.scsw.actl == 0) + ccw_device_set_timeout(cdev, 0); + /* Call the handler. */ + ccw_device_call_handler(cdev); + if (!sch->lpm) { + PREPARE_WORK(&cdev->private->kick_work, + ccw_device_nopath_notify, (void *)cdev); + queue_work(ccw_device_notify_work, &cdev->private->kick_work); + } else if (cdev->private->flags.doverify) + ccw_device_online_verify(cdev, 0); +} + +static void +ccw_device_wait4io_timeout(struct ccw_device *cdev, enum dev_event dev_event) +{ + int ret; + struct subchannel *sch; + + sch = to_subchannel(cdev->dev.parent); + ccw_device_set_timeout(cdev, 0); + ret = ccw_device_cancel_halt_clear(cdev); + if (ret == -EBUSY) { + ccw_device_set_timeout(cdev, 3*HZ); + cdev->private->state = DEV_STATE_TIMEOUT_KILL; + return; + } + if (ret == -ENODEV) { + if (!sch->lpm) { + PREPARE_WORK(&cdev->private->kick_work, + ccw_device_nopath_notify, (void *)cdev); + queue_work(ccw_device_notify_work, + &cdev->private->kick_work); + } else + dev_fsm_event(cdev, DEV_EVENT_NOTOPER); + return; + } + if (cdev->handler) + cdev->handler(cdev, cdev->private->intparm, + ERR_PTR(-ETIMEDOUT)); + if (!sch->lpm) { + PREPARE_WORK(&cdev->private->kick_work, + ccw_device_nopath_notify, (void *)cdev); + queue_work(ccw_device_notify_work, &cdev->private->kick_work); + } else if (cdev->private->flags.doverify) + /* Start delayed path verification. */ + ccw_device_online_verify(cdev, 0); +} + +static void +ccw_device_wait4io_verify(struct ccw_device *cdev, enum dev_event dev_event) +{ + /* When the I/O has terminated, we have to start verification. */ + if (cdev->private->options.pgroup) + cdev->private->flags.doverify = 1; +} + +static void +ccw_device_stlck_done(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct irb *irb; + + switch (dev_event) { + case DEV_EVENT_INTERRUPT: + irb = (struct irb *) __LC_IRB; + /* Check for unsolicited interrupt. */ + if ((irb->scsw.stctl == + (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) && + (!irb->scsw.cc)) + /* FIXME: we should restart stlck here, but this + * is extremely unlikely ... */ + goto out_wakeup; + + ccw_device_accumulate_irb(cdev, irb); + /* We don't care about basic sense etc. */ + break; + default: /* timeout */ + break; + } +out_wakeup: + wake_up(&cdev->private->wait_q); +} + +static void +ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct subchannel *sch; + + sch = to_subchannel(cdev->dev.parent); + if (cio_enable_subchannel(sch, sch->schib.pmcw.isc) != 0) + /* Couldn't enable the subchannel for i/o. Sick device. */ + return; + + /* After 60s the device recognition is considered to have failed. */ + ccw_device_set_timeout(cdev, 60*HZ); + + cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID; + ccw_device_sense_id_start(cdev); +} + +void +device_trigger_reprobe(struct subchannel *sch) +{ + struct ccw_device *cdev; + + if (!sch->dev.driver_data) + return; + cdev = sch->dev.driver_data; + if (cdev->private->state != DEV_STATE_DISCONNECTED) + return; + + /* Update some values. */ + if (stsch(sch->irq, &sch->schib)) + return; + + /* + * The pim, pam, pom values may not be accurate, but they are the best + * we have before performing device selection :/ + */ + sch->lpm = sch->schib.pmcw.pim & + sch->schib.pmcw.pam & + sch->schib.pmcw.pom & + sch->opm; + /* Re-set some bits in the pmcw that were lost. */ + sch->schib.pmcw.isc = 3; + sch->schib.pmcw.csense = 1; + sch->schib.pmcw.ena = 0; + if ((sch->lpm & (sch->lpm - 1)) != 0) + sch->schib.pmcw.mp = 1; + sch->schib.pmcw.intparm = (__u32)(unsigned long)sch; + /* We should also udate ssd info, but this has to wait. */ + ccw_device_start_id(cdev, 0); +} + +static void +ccw_device_offline_irq(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct subchannel *sch; + + sch = to_subchannel(cdev->dev.parent); + /* + * An interrupt in state offline means a previous disable was not + * successful. Try again. + */ + cio_disable_subchannel(sch); +} + +static void +ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event) +{ + retry_set_schib(cdev); + cdev->private->state = DEV_STATE_ONLINE; + dev_fsm_event(cdev, dev_event); +} + + +static void +ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event) +{ + ccw_device_set_timeout(cdev, 0); + if (dev_event == DEV_EVENT_NOTOPER) + cdev->private->state = DEV_STATE_NOT_OPER; + else + cdev->private->state = DEV_STATE_OFFLINE; + wake_up(&cdev->private->wait_q); +} + +static void +ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event) +{ + int ret; + + ret = ccw_device_cancel_halt_clear(cdev); + switch (ret) { + case 0: + cdev->private->state = DEV_STATE_OFFLINE; + wake_up(&cdev->private->wait_q); + break; + case -ENODEV: + cdev->private->state = DEV_STATE_NOT_OPER; + wake_up(&cdev->private->wait_q); + break; + default: + ccw_device_set_timeout(cdev, HZ/10); + } +} + +/* + * No operation action. This is used e.g. to ignore a timeout event in + * state offline. + */ +static void +ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event) +{ +} + +/* + * Bug operation action. + */ +static void +ccw_device_bug(struct ccw_device *cdev, enum dev_event dev_event) +{ + printk(KERN_EMERG "dev_jumptable[%i][%i] == NULL\n", + cdev->private->state, dev_event); + BUG(); +} + +/* + * device statemachine + */ +fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = { + [DEV_STATE_NOT_OPER] = { + [DEV_EVENT_NOTOPER] = ccw_device_nop, + [DEV_EVENT_INTERRUPT] = ccw_device_bug, + [DEV_EVENT_TIMEOUT] = ccw_device_nop, + [DEV_EVENT_VERIFY] = ccw_device_nop, + }, + [DEV_STATE_SENSE_PGID] = { + [DEV_EVENT_NOTOPER] = ccw_device_online_notoper, + [DEV_EVENT_INTERRUPT] = ccw_device_sense_pgid_irq, + [DEV_EVENT_TIMEOUT] = ccw_device_onoff_timeout, + [DEV_EVENT_VERIFY] = ccw_device_nop, + }, + [DEV_STATE_SENSE_ID] = { + [DEV_EVENT_NOTOPER] = ccw_device_recog_notoper, + [DEV_EVENT_INTERRUPT] = ccw_device_sense_id_irq, + [DEV_EVENT_TIMEOUT] = ccw_device_recog_timeout, + [DEV_EVENT_VERIFY] = ccw_device_nop, + }, + [DEV_STATE_OFFLINE] = { + [DEV_EVENT_NOTOPER] = ccw_device_offline_notoper, + [DEV_EVENT_INTERRUPT] = ccw_device_offline_irq, + [DEV_EVENT_TIMEOUT] = ccw_device_nop, + [DEV_EVENT_VERIFY] = ccw_device_nop, + }, + [DEV_STATE_VERIFY] = { + [DEV_EVENT_NOTOPER] = ccw_device_online_notoper, + [DEV_EVENT_INTERRUPT] = ccw_device_verify_irq, + [DEV_EVENT_TIMEOUT] = ccw_device_onoff_timeout, + [DEV_EVENT_VERIFY] = ccw_device_nop, + }, + [DEV_STATE_ONLINE] = { + [DEV_EVENT_NOTOPER] = ccw_device_online_notoper, + [DEV_EVENT_INTERRUPT] = ccw_device_irq, + [DEV_EVENT_TIMEOUT] = ccw_device_online_timeout, + [DEV_EVENT_VERIFY] = ccw_device_online_verify, + }, + [DEV_STATE_W4SENSE] = { + [DEV_EVENT_NOTOPER] = ccw_device_online_notoper, + [DEV_EVENT_INTERRUPT] = ccw_device_w4sense, + [DEV_EVENT_TIMEOUT] = ccw_device_nop, + [DEV_EVENT_VERIFY] = ccw_device_online_verify, + }, + [DEV_STATE_DISBAND_PGID] = { + [DEV_EVENT_NOTOPER] = ccw_device_online_notoper, + [DEV_EVENT_INTERRUPT] = ccw_device_disband_irq, + [DEV_EVENT_TIMEOUT] = ccw_device_onoff_timeout, + [DEV_EVENT_VERIFY] = ccw_device_nop, + }, + [DEV_STATE_BOXED] = { + [DEV_EVENT_NOTOPER] = ccw_device_offline_notoper, + [DEV_EVENT_INTERRUPT] = ccw_device_stlck_done, + [DEV_EVENT_TIMEOUT] = ccw_device_stlck_done, + [DEV_EVENT_VERIFY] = ccw_device_nop, + }, + /* states to wait for i/o completion before doing something */ + [DEV_STATE_CLEAR_VERIFY] = { + [DEV_EVENT_NOTOPER] = ccw_device_online_notoper, + [DEV_EVENT_INTERRUPT] = ccw_device_clear_verify, + [DEV_EVENT_TIMEOUT] = ccw_device_nop, + [DEV_EVENT_VERIFY] = ccw_device_nop, + }, + [DEV_STATE_TIMEOUT_KILL] = { + [DEV_EVENT_NOTOPER] = ccw_device_online_notoper, + [DEV_EVENT_INTERRUPT] = ccw_device_killing_irq, + [DEV_EVENT_TIMEOUT] = ccw_device_killing_timeout, + [DEV_EVENT_VERIFY] = ccw_device_nop, //FIXME + }, + [DEV_STATE_WAIT4IO] = { + [DEV_EVENT_NOTOPER] = ccw_device_online_notoper, + [DEV_EVENT_INTERRUPT] = ccw_device_wait4io_irq, + [DEV_EVENT_TIMEOUT] = ccw_device_wait4io_timeout, + [DEV_EVENT_VERIFY] = ccw_device_wait4io_verify, + }, + [DEV_STATE_QUIESCE] = { + [DEV_EVENT_NOTOPER] = ccw_device_quiesce_done, + [DEV_EVENT_INTERRUPT] = ccw_device_quiesce_done, + [DEV_EVENT_TIMEOUT] = ccw_device_quiesce_timeout, + [DEV_EVENT_VERIFY] = ccw_device_nop, + }, + /* special states for devices gone not operational */ + [DEV_STATE_DISCONNECTED] = { + [DEV_EVENT_NOTOPER] = ccw_device_nop, + [DEV_EVENT_INTERRUPT] = ccw_device_start_id, + [DEV_EVENT_TIMEOUT] = ccw_device_bug, + [DEV_EVENT_VERIFY] = ccw_device_nop, + }, + [DEV_STATE_DISCONNECTED_SENSE_ID] = { + [DEV_EVENT_NOTOPER] = ccw_device_recog_notoper, + [DEV_EVENT_INTERRUPT] = ccw_device_sense_id_irq, + [DEV_EVENT_TIMEOUT] = ccw_device_recog_timeout, + [DEV_EVENT_VERIFY] = ccw_device_nop, + }, + [DEV_STATE_CMFCHANGE] = { + [DEV_EVENT_NOTOPER] = ccw_device_change_cmfstate, + [DEV_EVENT_INTERRUPT] = ccw_device_change_cmfstate, + [DEV_EVENT_TIMEOUT] = ccw_device_change_cmfstate, + [DEV_EVENT_VERIFY] = ccw_device_change_cmfstate, + }, +}; + +/* + * io_subchannel_irq is called for "real" interrupts or for status + * pending conditions on msch. + */ +void +io_subchannel_irq (struct device *pdev) +{ + struct ccw_device *cdev; + + cdev = to_subchannel(pdev)->dev.driver_data; + + CIO_TRACE_EVENT (3, "IRQ"); + CIO_TRACE_EVENT (3, pdev->bus_id); + if (cdev) + dev_fsm_event(cdev, DEV_EVENT_INTERRUPT); +} + +EXPORT_SYMBOL_GPL(ccw_device_set_timeout); |