blob: 8633dc537695db3a99a03d35e462133fca0fa829 [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/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"
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_intretry(struct subchannel *sch)
{
struct ccw_device *cdev;
cdev = sch->dev.driver_data;
if (!cdev)
return;
cdev->private->flags.intretry = 1;
}
int device_trigger_verify(struct subchannel *sch)
{
struct ccw_device *cdev;
cdev = sch->dev.driver_data;
if (!cdev || !cdev->online)
return -EINVAL;
dev_fsm_event(cdev, DEV_EVENT_VERIFY);
return 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);
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)
/* Not operational -> 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);
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;
}
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.
*/
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) {
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_do_unreg_rereg);
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 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 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.pam & 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,
"cio: SenseID : unknown device %04x on subchannel "
"0.%x.%04x\n", cdev->private->dev_id.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 */
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;
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,
"cio: SenseID : device 0.%x.%04x reports: "
"CU Type/Mod = %04X/%02X, Dev Type/Mod = "
"%04X/%02X\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.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,
"cio: SenseID : boxed device %04x on subchannel "
"0.%x.%04x\n", cdev->private->dev_id.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(struct work_struct *work)
{
struct ccw_device_private *priv;
struct ccw_device *cdev;
struct subchannel *sch;
int ret;
unsigned long flags;
priv = container_of(work, struct ccw_device_private, kick_work);
cdev = priv->cdev;
spin_lock_irqsave(cdev->ccwlock, flags);
sch = to_subchannel(cdev->dev.parent);
if (sch->driver && sch->driver->notify) {
spin_unlock_irqrestore(cdev->ccwlock, flags);
ret = sch->driver->notify(&sch->dev, CIO_OPER);
spin_lock_irqsave(cdev->ccwlock, flags);
} else
ret = 0;
if (ret) {
/* Reenable channel measurements, if needed. */
spin_unlock_irqrestore(cdev->ccwlock, flags);
cmf_reenable(cdev);
spin_lock_irqsave(cdev->ccwlock, flags);
wake_up(&cdev->private->wait_q);
}
spin_unlock_irqrestore(cdev->ccwlock, flags);
if (!ret)
/* Driver doesn't want device back. */
ccw_device_do_unreg_rereg(work);
}
/*
* 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;
if (state == DEV_STATE_BOXED)
CIO_DEBUG(KERN_WARNING, 2,
"cio: Boxed device %04x on subchannel %04x\n",
cdev->private->dev_id.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);
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);
}
static int cmp_pgid(struct pgid *p1, struct pgid *p2)
{
char *c1;
char *c2;
c1 = (char *)p1;
c2 = (char *)p2;
return memcmp(c1 + 1, c2 + 1, sizeof(struct pgid) - 1);
}
static void __ccw_device_get_common_pgid(struct ccw_device *cdev)
{
int i;
int last;
last = 0;
for (i = 0; i < 8; i++) {
if (cdev->private->pgid[i].inf.ps.state1 == SNID_STATE1_RESET)
/* No PGID yet */
continue;
if (cdev->private->pgid[last].inf.ps.state1 ==
SNID_STATE1_RESET) {
/* First non-zero PGID */
last = i;
continue;
}
if (cmp_pgid(&cdev->private->pgid[i],
&cdev->private->pgid[last]) == 0)
/* Non-conflicting PGIDs */
continue;
/* PGID mismatch, can't pathgroup. */
CIO_MSG_EVENT(0, "SNID - pgid mismatch for device "
"0.%x.%04x, can't pathgroup\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
cdev->private->options.pgroup = 0;
return;
}
if (cdev->private->pgid[last].inf.ps.state1 ==
SNID_STATE1_RESET)
/* No previous pgid found */
memcpy(&cdev->private->pgid[0], &css[0]->global_pgid,
sizeof(struct pgid));
else
/* Use existing pgid */
memcpy(&cdev->private->pgid[0], &cdev->private->pgid[last],
sizeof(struct pgid));
}
/*
* 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 -EOPNOTSUPP: /* path grouping not supported, use nop instead. */
cdev->private->options.pgroup = 0;
break;
case 0: /* success */
case -EACCES: /* partial success, some paths not operational */
/* Check if all pgids are equal or 0. */
__ccw_device_get_common_pgid(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);
return;
default:
ccw_device_done(cdev, DEV_STATE_NOT_OPER);
return;
}
/* Start Path Group verification. */
cdev->private->state = DEV_STATE_VERIFY;
cdev->private->flags.doverify = 0;
ccw_device_verify_start(cdev);
}
/*
* 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(struct work_struct *work)
{
struct ccw_device_private *priv;
struct ccw_device *cdev;
struct subchannel *sch;
int ret;
unsigned long flags;
priv = container_of(work, struct ccw_device_private, kick_work);
cdev = priv->cdev;
spin_lock_irqsave(cdev->ccwlock, flags);
sch = to_subchannel(cdev->dev.parent);
/* Extra sanity. */
if (sch->lpm)
goto out_unlock;
if (sch->driver && sch->driver->notify) {
spin_unlock_irqrestore(cdev->ccwlock, flags);
ret = sch->driver->notify(&sch->dev, CIO_NO_PATH);
spin_lock_irqsave(cdev->ccwlock, flags);
} else
ret = 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);
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);
}
out_unlock:
spin_unlock_irqrestore(cdev->ccwlock, flags);
}
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. */
stsch(sch->schid, &sch->schib);
/* Update lpm with verified path mask. */
sch->lpm = sch->vpm;
/* Repeat path verification? */
if (cdev->private->flags.doverify) {
cdev->private->flags.doverify = 0;
ccw_device_verify_start(cdev);
return;
}
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.cc = 1;
cdev->private->irb.scsw.fctl = SCSW_FCTL_START_FUNC;
cdev->private->irb.scsw.actl = SCSW_ACTL_START_PEND;
cdev->private->irb.scsw.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:
/* Reset oper notify indication after verify error. */
cdev->private->flags.donotify = 0;
ccw_device_done(cdev, DEV_STATE_BOXED);
break;
default:
/* Reset oper notify indication after verify error. */
cdev->private->flags.donotify = 0;
if (cdev->online) {
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_nopath_notify);
queue_work(ccw_device_notify_work,
&cdev->private->kick_work);
} else
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) {
/* Start initial path verification. */
cdev->private->state = DEV_STATE_VERIFY;
cdev->private->flags.doverify = 0;
ccw_device_verify_start(cdev);
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:
cdev->private->flags.donotify = 0;
if (get_device(&cdev->dev)) {
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_call_sch_unregister);
queue_work(ccw_device_work, &cdev->private->kick_work);
}
ccw_device_done(cdev, DEV_STATE_NOT_OPER);
break;
}
}
/*
* Shutdown device.
*/
int
ccw_device_offline(struct ccw_device *cdev)
{
struct subchannel *sch;
if (ccw_device_is_orphan(cdev)) {
ccw_device_done(cdev, DEV_STATE_OFFLINE);
return 0;
}
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);
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;
int ret;
sch = to_subchannel(cdev->dev.parent);
if (sch->driver->notify) {
spin_unlock_irq(cdev->ccwlock);
ret = sch->driver->notify(&sch->dev,
sch->lpm ? CIO_GONE : CIO_NO_PATH);
spin_lock_irq(cdev->ccwlock);
} else
ret = 0;
if (ret) {
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);
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->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 ||
(sch->schib.scsw.stctl & SCSW_STCTL_STATUS_PEND) ||
(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;
cdev->private->flags.doverify = 0;
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);
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 (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);
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.
*/
static 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 {
CIO_MSG_EVENT(2, "Huh? 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 (irb->scsw.fctl & (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
/* Retry Basic Sense if requested. */
if (cdev->private->flags.intretry) {
cdev->private->flags.intretry = 0;
ccw_device_do_sense(cdev, irb);
return;
}
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);
/* Remember to clear irb to avoid residuals. */
memset(&cdev->private->irb, 0, sizeof(struct 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);
/* 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 device_kill_io(struct subchannel *sch)
{
int ret;
struct ccw_device *cdev;
cdev = sch->dev.driver_data;
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_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;
if (!sch->schib.pmcw.dnv)
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;
/* 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. */
/* Check if this is another device which appeared on the same sch. */
if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_move_to_orphanage);
queue_work(ccw_device_work, &cdev->private->kick_work);
} else
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_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);
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)
{
CIO_MSG_EVENT(0, "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_delay_verify,
},
[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_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_start_id,
},
[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,
},
[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,
},
};
/*
* 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);