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remarkable-linux/drivers/s390/cio/device_fsm.c
Cornelia Huck 7e560814de [S390] path grouping and path verifications fixes. 
1. Multipath devices for which SetPGID is not supported are not handled well.
   Use NOP ccws for path verification (sans path grouping) when SetPGID is not
   supported.
2. Check for PGIDs already set with SensePGID on _all_ paths (not just the
   first one) and try to find a common one. Moan if no common PGID can be
   found (and use NOP verification). If no PGIDs have been set, use the css
   global PGID (as before). (Rationale: SetPGID will get a command reject if
   the PGID it tries to set does not match the already set PGID.)
3. Immediately before reboot, issue RESET CHANNEL PATH (rcp) on all chpids. This
   will remove the old PGIDs. rcp will generate solicited CRWs which can be
   savely ignored by the machine check handler (all other actions create
   unsolicited CRWs).

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-07-12 16:40:19 +02:00

1338 lines
35 KiB
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/*
* 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 "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 {
/* Reenable channel measurements, if needed. */
cmf_reenable(cdev);
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);
}
static inline 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->ssid, cdev->private->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. */
sch->vpm = 0; /* Start with no path groups set. */
cdev->private->state = DEV_STATE_VERIFY;
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(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) {
/* Start initial path verification. */
cdev->private->state = DEV_STATE_VERIFY;
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:
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. */
sch->vpm = 0;
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->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);
/* 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);
/* 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. */
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_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)
{
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,
},
[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);
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