blob: 49ec562d7f60b7d9d5d3c7658851394c11020d8d [file] [log] [blame]
/*
* 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 (cornelia.huck@de.ibm.com)
* Martin Schwidefsky (schwidefsky@de.ibm.com)
*/
#include <linux/module.h>
#include <linux/config.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include <linux/string.h>
#include <asm/ccwdev.h>
#include <asm/cio.h>
#include "cio.h"
#include "cio_debug.h"
#include "css.h"
#include "device.h"
#include "chsc.h"
#include "ioasm.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->schid, &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->schid, &sch->schib);
sch->lpm = sch->schib.pmcw.pim &
sch->schib.pmcw.pam &
sch->schib.pmcw.pom &
sch->opm;
/* Check since device may again have become not operational. */
if (!sch->schib.pmcw.dnv)
state = DEV_STATE_NOT_OPER;
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 "
"0.%x.%04x\n", cdev->private->devno,
sch->schid.ssid, sch->schid.sch_no);
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 0.%x.%04x reports: "
"CU Type/Mod = %04X/%02X, Dev Type/Mod = "
"%04X/%02X\n",
cdev->private->ssid, 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 "
"0.%x.%04x\n", cdev->private->devno,
sch->schid.ssid, sch->schid.sch_no);
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->schid.sch_no);
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->schid, &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->schid, &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(&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);
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;
}
/*
* 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 (irb->scsw.fctl & (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;
/* 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->schid, &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->schid, &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);