--- /dev/null
+/*
+ * finite state machine for device handling
+ *
+ * Copyright IBM Corp. 2002, 2008
+ * Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
+ * Martin Schwidefsky (schwidefsky@de.ibm.com)
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/string.h>
+
+#include <asm/ccwdev.h>
+#include <asm/cio.h>
+#include <asm/chpid.h>
+
+#include "cio.h"
+#include "cio_debug.h"
+#include "css.h"
+#include "device.h"
+#include "chsc.h"
+#include "ioasm.h"
+#include "chp.h"
+
+static int timeout_log_enabled;
+
+static int __init ccw_timeout_log_setup(char *unused)
+{
+ timeout_log_enabled = 1;
+ return 1;
+}
+
+__setup("ccw_timeout_log", ccw_timeout_log_setup);
+
+static void ccw_timeout_log(struct ccw_device *cdev)
+{
+ struct schib schib;
+ struct subchannel *sch;
+ struct io_subchannel_private *private;
+ union orb *orb;
+ int cc;
+
+ sch = to_subchannel(cdev->dev.parent);
+ private = to_io_private(sch);
+ orb = &private->orb;
+ cc = stsch_err(sch->schid, &schib);
+
+ printk(KERN_WARNING "cio: ccw device timeout occurred at %llx, "
+ "device information:\n", get_tod_clock());
+ printk(KERN_WARNING "cio: orb:\n");
+ print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
+ orb, sizeof(*orb), 0);
+ printk(KERN_WARNING "cio: ccw device bus id: %s\n",
+ dev_name(&cdev->dev));
+ printk(KERN_WARNING "cio: subchannel bus id: %s\n",
+ dev_name(&sch->dev));
+ printk(KERN_WARNING "cio: subchannel lpm: %02x, opm: %02x, "
+ "vpm: %02x\n", sch->lpm, sch->opm, sch->vpm);
+
+ if (orb->tm.b) {
+ printk(KERN_WARNING "cio: orb indicates transport mode\n");
+ printk(KERN_WARNING "cio: last tcw:\n");
+ print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
+ (void *)(addr_t)orb->tm.tcw,
+ sizeof(struct tcw), 0);
+ } else {
+ printk(KERN_WARNING "cio: orb indicates command mode\n");
+ if ((void *)(addr_t)orb->cmd.cpa == &private->sense_ccw ||
+ (void *)(addr_t)orb->cmd.cpa == cdev->private->iccws)
+ printk(KERN_WARNING "cio: last channel program "
+ "(intern):\n");
+ else
+ printk(KERN_WARNING "cio: last channel program:\n");
+
+ print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
+ (void *)(addr_t)orb->cmd.cpa,
+ sizeof(struct ccw1), 0);
+ }
+ printk(KERN_WARNING "cio: ccw device state: %d\n",
+ cdev->private->state);
+ printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc);
+ printk(KERN_WARNING "cio: schib:\n");
+ print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
+ &schib, sizeof(schib), 0);
+ printk(KERN_WARNING "cio: ccw device flags:\n");
+ print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
+ &cdev->private->flags, sizeof(cdev->private->flags), 0);
+}
+
+/*
+ * 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);
+ if (timeout_log_enabled)
+ ccw_timeout_log(cdev);
+ 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);
+}
+
+/*
+ * 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);
+ if (cio_update_schib(sch))
+ return -ENODEV;
+ if (!sch->schib.pmcw.ena)
+ /* Not operational -> done. */
+ return 0;
+ /* Stage 1: cancel io. */
+ if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_HALT_PEND) &&
+ !(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
+ if (!scsw_is_tm(&sch->schib.scsw)) {
+ ret = cio_cancel(sch);
+ if (ret != -EINVAL)
+ return ret;
+ }
+ /* cancel io unsuccessful or not applicable (transport mode).
+ * Continue with asynchronous instructions. */
+ cdev->private->iretry = 3; /* 3 halt retries. */
+ }
+ if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
+ /* Stage 2: halt io. */
+ if (cdev->private->iretry) {
+ cdev->private->iretry--;
+ ret = cio_halt(sch);
+ if (ret != -EBUSY)
+ 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;
+ }
+ /* Function was unsuccessful */
+ CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n",
+ cdev->private->dev_id.ssid, cdev->private->dev_id.devno);
+ return -EIO;
+}
+
+void ccw_device_update_sense_data(struct ccw_device *cdev)
+{
+ memset(&cdev->id, 0, sizeof(cdev->id));
+ 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;
+}
+
+int ccw_device_test_sense_data(struct ccw_device *cdev)
+{
+ return 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;
+}
+
+/*
+ * 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 void
+__recover_lost_chpids(struct subchannel *sch, int old_lpm)
+{
+ int mask, i;
+ struct chp_id chpid;
+
+ chp_id_init(&chpid);
+ for (i = 0; i<8; i++) {
+ mask = 0x80 >> i;
+ if (!(sch->lpm & mask))
+ continue;
+ if (old_lpm & mask)
+ continue;
+ chpid.id = sch->schib.pmcw.chpid[i];
+ if (!chp_is_registered(chpid))
+ css_schedule_eval_all();
+ }
+}
+
+/*
+ * Stop device recognition.
+ */
+static void
+ccw_device_recog_done(struct ccw_device *cdev, int state)
+{
+ struct subchannel *sch;
+ int old_lpm;
+
+ sch = to_subchannel(cdev->dev.parent);
+
+ if (cio_disable_subchannel(sch))
+ state = DEV_STATE_NOT_OPER;
+ /*
+ * Now that we tried recognition, we have performed device selection
+ * through ssch() and the path information is up to date.
+ */
+ old_lpm = sch->lpm;
+
+ /* Check since device may again have become not operational. */
+ if (cio_update_schib(sch))
+ state = DEV_STATE_NOT_OPER;
+ else
+ sch->lpm = sch->schib.pmcw.pam & 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 &&
+ (state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) {
+ cdev->private->flags.recog_done = 1;
+ cdev->private->state = DEV_STATE_DISCONNECTED;
+ wake_up(&cdev->private->wait_q);
+ return;
+ }
+ if (cdev->private->flags.resuming) {
+ cdev->private->state = state;
+ cdev->private->flags.recog_done = 1;
+ wake_up(&cdev->private->wait_q);
+ return;
+ }
+ switch (state) {
+ case DEV_STATE_NOT_OPER:
+ break;
+ case DEV_STATE_OFFLINE:
+ if (!cdev->online) {
+ ccw_device_update_sense_data(cdev);
+ break;
+ }
+ cdev->private->state = DEV_STATE_OFFLINE;
+ cdev->private->flags.recog_done = 1;
+ if (ccw_device_test_sense_data(cdev)) {
+ cdev->private->flags.donotify = 1;
+ ccw_device_online(cdev);
+ wake_up(&cdev->private->wait_q);
+ } else {
+ ccw_device_update_sense_data(cdev);
+ ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
+ }
+ return;
+ case DEV_STATE_BOXED:
+ if (cdev->id.cu_type != 0) { /* device was recognized before */
+ cdev->private->flags.recog_done = 1;
+ cdev->private->state = DEV_STATE_BOXED;
+ wake_up(&cdev->private->wait_q);
+ return;
+ }
+ break;
+ }
+ cdev->private->state = state;
+ io_subchannel_recog_done(cdev);
+ 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;
+ }
+}
+
+/**
+ * ccw_device_notify() - inform the device's driver about an event
+ * @cdev: device for which an event occurred
+ * @event: event that occurred
+ *
+ * Returns:
+ * -%EINVAL if the device is offline or has no driver.
+ * -%EOPNOTSUPP if the device's driver has no notifier registered.
+ * %NOTIFY_OK if the driver wants to keep the device.
+ * %NOTIFY_BAD if the driver doesn't want to keep the device.
+ */
+int ccw_device_notify(struct ccw_device *cdev, int event)
+{
+ int ret = -EINVAL;
+
+ if (!cdev->drv)
+ goto out;
+ if (!cdev->online)
+ goto out;
+ CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
+ cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
+ event);
+ if (!cdev->drv->notify) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
+ if (cdev->drv->notify(cdev, event))
+ ret = NOTIFY_OK;
+ else
+ ret = NOTIFY_BAD;
+out:
+ return ret;
+}
+
+static void ccw_device_oper_notify(struct ccw_device *cdev)
+{
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+
+ if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) {
+ /* Reenable channel measurements, if needed. */
+ ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
+ /* Save indication for new paths. */
+ cdev->private->path_new_mask = sch->vpm;
+ return;
+ }
+ /* Driver doesn't want device back. */
+ ccw_device_set_notoper(cdev);
+ ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
+}
+
+/*
+ * 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);
+
+ ccw_device_set_timeout(cdev, 0);
+
+ if (state != DEV_STATE_ONLINE)
+ cio_disable_subchannel(sch);
+
+ /* Reset device status. */
+ memset(&cdev->private->irb, 0, sizeof(struct irb));
+
+ cdev->private->state = state;
+
+ switch (state) {
+ case DEV_STATE_BOXED:
+ CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
+ cdev->private->dev_id.devno, sch->schid.sch_no);
+ if (cdev->online &&
+ ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK)
+ ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
+ cdev->private->flags.donotify = 0;
+ break;
+ case DEV_STATE_NOT_OPER:
+ CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
+ cdev->private->dev_id.devno, sch->schid.sch_no);
+ if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
+ ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
+ else
+ ccw_device_set_disconnected(cdev);
+ cdev->private->flags.donotify = 0;
+ break;
+ case DEV_STATE_DISCONNECTED:
+ CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
+ "%04x\n", cdev->private->dev_id.devno,
+ sch->schid.sch_no);
+ if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) {
+ cdev->private->state = DEV_STATE_NOT_OPER;
+ ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
+ } else
+ ccw_device_set_disconnected(cdev);
+ cdev->private->flags.donotify = 0;
+ break;
+ default:
+ break;
+ }
+
+ if (cdev->private->flags.donotify) {
+ cdev->private->flags.donotify = 0;
+ ccw_device_oper_notify(cdev);
+ }
+ wake_up(&cdev->private->wait_q);
+}
+
+/*
+ * Start device recognition.
+ */
+void ccw_device_recognition(struct ccw_device *cdev)
+{
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+
+ /*
+ * 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;
+ if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) {
+ ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
+ return;
+ }
+ ccw_device_sense_id_start(cdev);
+}
+
+/*
+ * Handle events for states that use the ccw request infrastructure.
+ */
+static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
+{
+ switch (e) {
+ case DEV_EVENT_NOTOPER:
+ ccw_request_notoper(cdev);
+ break;
+ case DEV_EVENT_INTERRUPT:
+ ccw_request_handler(cdev);
+ break;
+ case DEV_EVENT_TIMEOUT:
+ ccw_request_timeout(cdev);
+ break;
+ default:
+ break;
+ }
+}
+
+static void ccw_device_report_path_events(struct ccw_device *cdev)
+{
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+ int path_event[8];
+ int chp, mask;
+
+ for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) {
+ path_event[chp] = PE_NONE;
+ if (mask & cdev->private->path_gone_mask & ~(sch->vpm))
+ path_event[chp] |= PE_PATH_GONE;
+ if (mask & cdev->private->path_new_mask & sch->vpm)
+ path_event[chp] |= PE_PATH_AVAILABLE;
+ if (mask & cdev->private->pgid_reset_mask & sch->vpm)
+ path_event[chp] |= PE_PATHGROUP_ESTABLISHED;
+ }
+ if (cdev->online && cdev->drv->path_event)
+ cdev->drv->path_event(cdev, path_event);
+}
+
+static void ccw_device_reset_path_events(struct ccw_device *cdev)
+{
+ cdev->private->path_gone_mask = 0;
+ cdev->private->path_new_mask = 0;
+ cdev->private->pgid_reset_mask = 0;
+}
+
+static void create_fake_irb(struct irb *irb, int type)
+{
+ memset(irb, 0, sizeof(*irb));
+ if (type == FAKE_CMD_IRB) {
+ struct cmd_scsw *scsw = &irb->scsw.cmd;
+ scsw->cc = 1;
+ scsw->fctl = SCSW_FCTL_START_FUNC;
+ scsw->actl = SCSW_ACTL_START_PEND;
+ scsw->stctl = SCSW_STCTL_STATUS_PEND;
+ } else if (type == FAKE_TM_IRB) {
+ struct tm_scsw *scsw = &irb->scsw.tm;
+ scsw->x = 1;
+ scsw->cc = 1;
+ scsw->fctl = SCSW_FCTL_START_FUNC;
+ scsw->actl = SCSW_ACTL_START_PEND;
+ scsw->stctl = SCSW_STCTL_STATUS_PEND;
+ }
+}
+
+void ccw_device_verify_done(struct ccw_device *cdev, int err)
+{
+ struct subchannel *sch;
+
+ sch = to_subchannel(cdev->dev.parent);
+ /* Update schib - pom may have changed. */
+ if (cio_update_schib(sch)) {
+ err = -ENODEV;
+ goto callback;
+ }
+ /* Update lpm with verified path mask. */
+ sch->lpm = sch->vpm;
+ /* Repeat path verification? */
+ if (cdev->private->flags.doverify) {
+ ccw_device_verify_start(cdev);
+ return;
+ }
+callback:
+ switch (err) {
+ case 0:
+ ccw_device_done(cdev, DEV_STATE_ONLINE);
+ /* Deliver fake irb to device driver, if needed. */
+ if (cdev->private->flags.fake_irb) {
+ create_fake_irb(&cdev->private->irb,
+ cdev->private->flags.fake_irb);
+ 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));
+ }
+ ccw_device_report_path_events(cdev);
+ break;
+ case -ETIME:
+ case -EUSERS:
+ /* Reset oper notify indication after verify error. */
+ cdev->private->flags.donotify = 0;
+ ccw_device_done(cdev, DEV_STATE_BOXED);
+ break;
+ case -EACCES:
+ /* Reset oper notify indication after verify error. */
+ cdev->private->flags.donotify = 0;
+ ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
+ break;
+ default:
+ /* Reset oper notify indication after verify error. */
+ cdev->private->flags.donotify = 0;
+ ccw_device_done(cdev, DEV_STATE_NOT_OPER);
+ break;
+ }
+ ccw_device_reset_path_events(cdev);
+}
+
+/*
+ * 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);
+ ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
+ 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;
+ }
+ /* Start initial path verification. */
+ cdev->private->state = DEV_STATE_VERIFY;
+ ccw_device_verify_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:
+ cdev->private->flags.donotify = 0;
+ ccw_device_done(cdev, DEV_STATE_NOT_OPER);
+ break;
+ }
+}
+
+/*
+ * Shutdown device.
+ */
+int
+ccw_device_offline(struct ccw_device *cdev)
+{
+ struct subchannel *sch;
+
+ /* Allow ccw_device_offline while disconnected. */
+ if (cdev->private->state == DEV_STATE_DISCONNECTED ||
+ cdev->private->state == DEV_STATE_NOT_OPER) {
+ cdev->private->flags.donotify = 0;
+ ccw_device_done(cdev, DEV_STATE_NOT_OPER);
+ return 0;
+ }
+ if (cdev->private->state == DEV_STATE_BOXED) {
+ ccw_device_done(cdev, DEV_STATE_BOXED);
+ return 0;
+ }
+ if (ccw_device_is_orphan(cdev)) {
+ ccw_device_done(cdev, DEV_STATE_OFFLINE);
+ return 0;
+ }
+ sch = to_subchannel(cdev->dev.parent);
+ if (cio_update_schib(sch))
+ return -ENODEV;
+ if (scsw_actl(&sch->schib.scsw) != 0)
+ return -EBUSY;
+ if (cdev->private->state != DEV_STATE_ONLINE)
+ return -EINVAL;
+ /* Are we doing path grouping? */
+ if (!cdev->private->flags.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 not operational event in non-special state.
+ */
+static void ccw_device_generic_notoper(struct ccw_device *cdev,
+ enum dev_event dev_event)
+{
+ if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
+ ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
+ else
+ ccw_device_set_disconnected(cdev);
+}
+
+/*
+ * Handle path verification event in offline state.
+ */
+static void ccw_device_offline_verify(struct ccw_device *cdev,
+ enum dev_event dev_event)
+{
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+
+ css_schedule_eval(sch->schid);
+}
+
+/*
+ * 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->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.
+ */
+ if (cio_update_schib(sch)) {
+ ccw_device_verify_done(cdev, -ENODEV);
+ return;
+ }
+
+ if (scsw_actl(&sch->schib.scsw) != 0 ||
+ (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
+ (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) {
+ /*
+ * No final status yet or final status not yet delivered
+ * to the device driver. Can't do path verification 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);
+}
+
+/*
+ * Handle path verification event in boxed state.
+ */
+static void ccw_device_boxed_verify(struct ccw_device *cdev,
+ enum dev_event dev_event)
+{
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+
+ if (cdev->online) {
+ if (cio_enable_subchannel(sch, (u32) (addr_t) sch))
+ ccw_device_done(cdev, DEV_STATE_NOT_OPER);
+ else
+ ccw_device_online_verify(cdev, dev_event);
+ } else
+ css_schedule_eval(sch->schid);
+}
+
+/*
+ * 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;
+ int is_cmd;
+
+ irb = this_cpu_ptr(&cio_irb);
+ is_cmd = !scsw_is_tm(&irb->scsw);
+ /* Check for unsolicited interrupt. */
+ if (!scsw_is_solicited(&irb->scsw)) {
+ if (is_cmd && (irb->scsw.cmd.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(&cdev->private->irb, 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);
+ if (cdev->private->flags.doverify)
+ ccw_device_online_verify(cdev, 0);
+ return;
+ }
+ /* Accumulate status and find out if a basic sense is needed. */
+ ccw_device_accumulate_irb(cdev, irb);
+ if (is_cmd && 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);
+ cdev->private->iretry = 255;
+ 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)
+ 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.
+ */
+static void
+ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
+{
+ struct irb *irb;
+
+ irb = this_cpu_ptr(&cio_irb);
+ /* Check for unsolicited interrupt. */
+ if (scsw_stctl(&irb->scsw) ==
+ (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
+ if (scsw_cc(&irb->scsw) == 1)
+ /* Basic sense hasn't started. Try again. */
+ ccw_device_do_sense(cdev, irb);
+ else {
+ CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
+ "interrupt during w4sense...\n",
+ cdev->private->dev_id.ssid,
+ cdev->private->dev_id.devno);
+ if (cdev->handler)
+ cdev->handler (cdev, 0, irb);
+ }
+ return;
+ }
+ /*
+ * Check if a halt or clear has been issued in the meanwhile. If yes,
+ * only deliver the halt/clear interrupt to the device driver as if it
+ * had killed the original request.
+ */
+ if (scsw_fctl(&irb->scsw) &
+ (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
+ cdev->private->flags.dosense = 0;
+ memset(&cdev->private->irb, 0, sizeof(struct irb));
+ ccw_device_accumulate_irb(cdev, irb);
+ goto call_handler;
+ }
+ /* 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;
+ }
+call_handler:
+ cdev->private->state = DEV_STATE_ONLINE;
+ /* In case sensing interfered with setting the device online */
+ wake_up(&cdev->private->wait_q);
+ /* 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_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
+{
+ ccw_device_set_timeout(cdev, 0);
+ /* Start delayed path verification. */
+ ccw_device_online_verify(cdev, 0);
+ /* OK, i/o is dead now. Call interrupt handler. */
+ if (cdev->handler)
+ cdev->handler(cdev, cdev->private->intparm,
+ ERR_PTR(-EIO));
+}
+
+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;
+ }
+ /* Start delayed path verification. */
+ ccw_device_online_verify(cdev, 0);
+ if (cdev->handler)
+ cdev->handler(cdev, cdev->private->intparm,
+ ERR_PTR(-EIO));
+}
+
+void ccw_device_kill_io(struct ccw_device *cdev)
+{
+ int ret;
+
+ cdev->private->iretry = 255;
+ 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;
+ }
+ /* Start delayed path verification. */
+ ccw_device_online_verify(cdev, 0);
+ if (cdev->handler)
+ cdev->handler(cdev, cdev->private->intparm,
+ ERR_PTR(-EIO));
+}
+
+static void
+ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
+{
+ /* Start verification after current task finished. */
+ cdev->private->flags.doverify = 1;
+}
+
+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, (u32)(addr_t)sch) != 0)
+ /* Couldn't enable the subchannel for i/o. Sick device. */
+ return;
+ cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
+ ccw_device_sense_id_start(cdev);
+}
+
+void ccw_device_trigger_reprobe(struct ccw_device *cdev)
+{
+ struct subchannel *sch;
+
+ if (cdev->private->state != DEV_STATE_DISCONNECTED)
+ return;
+
+ sch = to_subchannel(cdev->dev.parent);
+ /* Update some values. */
+ if (cio_update_schib(sch))
+ 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.pam & sch->opm;
+ /*
+ * Use the initial configuration since we can't be shure that the old
+ * paths are valid.
+ */
+ io_subchannel_init_config(sch);
+ if (cio_commit_config(sch))
+ return;
+
+ /* We should also udate ssd info, but this has to wait. */
+ /* Check if this is another device which appeared on the same sch. */
+ if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
+ css_schedule_eval(sch->schid);
+ else
+ ccw_device_start_id(cdev, 0);
+}
+
+static void ccw_device_disabled_irq(struct ccw_device *cdev,
+ enum dev_event dev_event)
+{
+ struct subchannel *sch;
+
+ sch = to_subchannel(cdev->dev.parent);
+ /*
+ * An interrupt in a disabled state means a previous disable was not
+ * successful - should not happen, but we try to disable 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_update_cmfblock(struct ccw_device *cdev,
+ enum dev_event dev_event)
+{
+ cmf_retry_copy_block(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);
+ cdev->private->state = DEV_STATE_NOT_OPER;
+ 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);
+ if (ret == -EBUSY) {
+ ccw_device_set_timeout(cdev, HZ/10);
+ } else {
+ cdev->private->state = DEV_STATE_NOT_OPER;
+ wake_up(&cdev->private->wait_q);
+ }
+}
+
+/*
+ * 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)
+{
+}
+
+/*
+ * 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_disabled_irq,
+ [DEV_EVENT_TIMEOUT] = ccw_device_nop,
+ [DEV_EVENT_VERIFY] = ccw_device_nop,
+ },
+ [DEV_STATE_SENSE_PGID] = {
+ [DEV_EVENT_NOTOPER] = ccw_device_request_event,
+ [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
+ [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
+ [DEV_EVENT_VERIFY] = ccw_device_nop,
+ },
+ [DEV_STATE_SENSE_ID] = {
+ [DEV_EVENT_NOTOPER] = ccw_device_request_event,
+ [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
+ [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
+ [DEV_EVENT_VERIFY] = ccw_device_nop,
+ },
+ [DEV_STATE_OFFLINE] = {
+ [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
+ [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq,
+ [DEV_EVENT_TIMEOUT] = ccw_device_nop,
+ [DEV_EVENT_VERIFY] = ccw_device_offline_verify,
+ },
+ [DEV_STATE_VERIFY] = {
+ [DEV_EVENT_NOTOPER] = ccw_device_request_event,
+ [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
+ [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
+ [DEV_EVENT_VERIFY] = ccw_device_delay_verify,
+ },
+ [DEV_STATE_ONLINE] = {
+ [DEV_EVENT_NOTOPER] = ccw_device_generic_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_generic_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_request_event,
+ [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
+ [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
+ [DEV_EVENT_VERIFY] = ccw_device_nop,
+ },
+ [DEV_STATE_BOXED] = {
+ [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
+ [DEV_EVENT_INTERRUPT] = ccw_device_nop,
+ [DEV_EVENT_TIMEOUT] = ccw_device_nop,
+ [DEV_EVENT_VERIFY] = ccw_device_boxed_verify,
+ },
+ /* states to wait for i/o completion before doing something */
+ [DEV_STATE_TIMEOUT_KILL] = {
+ [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
+ [DEV_EVENT_INTERRUPT] = ccw_device_killing_irq,
+ [DEV_EVENT_TIMEOUT] = ccw_device_killing_timeout,
+ [DEV_EVENT_VERIFY] = ccw_device_nop, //FIXME
+ },
+ [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_nop,
+ [DEV_EVENT_VERIFY] = ccw_device_start_id,
+ },
+ [DEV_STATE_DISCONNECTED_SENSE_ID] = {
+ [DEV_EVENT_NOTOPER] = ccw_device_request_event,
+ [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
+ [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
+ [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,
+ },
+ [DEV_STATE_CMFUPDATE] = {
+ [DEV_EVENT_NOTOPER] = ccw_device_update_cmfblock,
+ [DEV_EVENT_INTERRUPT] = ccw_device_update_cmfblock,
+ [DEV_EVENT_TIMEOUT] = ccw_device_update_cmfblock,
+ [DEV_EVENT_VERIFY] = ccw_device_update_cmfblock,
+ },
+ [DEV_STATE_STEAL_LOCK] = {
+ [DEV_EVENT_NOTOPER] = ccw_device_request_event,
+ [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
+ [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
+ [DEV_EVENT_VERIFY] = ccw_device_nop,
+ },
+};
+
+EXPORT_SYMBOL_GPL(ccw_device_set_timeout);
Code Review / kvmfornfv.git / blobdiff