linux/drivers/s390/cio/device_fsm.c
Michael Ernst 217ee6c64a [S390] cio: failing set online/offline processing.
When unit checks trigger sensing the device state is set to W4SENSE
until sense completion; then the device state is set back to
ONLINE. If a unit check occurs while set online or set offline
requests are processed then it might happen that the device's
temporary W4SENSE state causes these functions to terminate,
leaving the device in an inconsistent state when the state is set
back to ONLINE later on so that the device cannot be set online or
offline any longer.
To solve this, set online/offline and related rollback or error
routines are processed only if the device is in a final or
DISCONNECTED state.

Signed-off-by: Michael Ernst <mernst@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11 10:29:38 +02:00

1251 lines
34 KiB
C

/*
* drivers/s390/cio/device_fsm.c
* finite state machine for device handling
*
* Copyright IBM Corp. 2002,2008
* Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
* Martin Schwidefsky (schwidefsky@de.ibm.com)
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include <linux/string.h>
#include <asm/ccwdev.h>
#include <asm/cio.h>
#include <asm/chpid.h>
#include "cio.h"
#include "cio_debug.h"
#include "css.h"
#include "device.h"
#include "chsc.h"
#include "ioasm.h"
#include "chp.h"
static int timeout_log_enabled;
static int __init ccw_timeout_log_setup(char *unused)
{
timeout_log_enabled = 1;
return 1;
}
__setup("ccw_timeout_log", ccw_timeout_log_setup);
static void ccw_timeout_log(struct ccw_device *cdev)
{
struct schib schib;
struct subchannel *sch;
struct io_subchannel_private *private;
union orb *orb;
int cc;
sch = to_subchannel(cdev->dev.parent);
private = to_io_private(sch);
orb = &private->orb;
cc = stsch(sch->schid, &schib);
printk(KERN_WARNING "cio: ccw device timeout occurred at %llx, "
"device information:\n", get_clock());
printk(KERN_WARNING "cio: orb:\n");
print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
orb, sizeof(*orb), 0);
printk(KERN_WARNING "cio: ccw device bus id: %s\n",
dev_name(&cdev->dev));
printk(KERN_WARNING "cio: subchannel bus id: %s\n",
dev_name(&sch->dev));
printk(KERN_WARNING "cio: subchannel lpm: %02x, opm: %02x, "
"vpm: %02x\n", sch->lpm, sch->opm, sch->vpm);
if (orb->tm.b) {
printk(KERN_WARNING "cio: orb indicates transport mode\n");
printk(KERN_WARNING "cio: last tcw:\n");
print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
(void *)(addr_t)orb->tm.tcw,
sizeof(struct tcw), 0);
} else {
printk(KERN_WARNING "cio: orb indicates command mode\n");
if ((void *)(addr_t)orb->cmd.cpa == &private->sense_ccw ||
(void *)(addr_t)orb->cmd.cpa == cdev->private->iccws)
printk(KERN_WARNING "cio: last channel program "
"(intern):\n");
else
printk(KERN_WARNING "cio: last channel program:\n");
print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
(void *)(addr_t)orb->cmd.cpa,
sizeof(struct ccw1), 0);
}
printk(KERN_WARNING "cio: ccw device state: %d\n",
cdev->private->state);
printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc);
printk(KERN_WARNING "cio: schib:\n");
print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
&schib, sizeof(schib), 0);
printk(KERN_WARNING "cio: ccw device flags:\n");
print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
&cdev->private->flags, sizeof(cdev->private->flags), 0);
}
/*
* Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
*/
static void
ccw_device_timeout(unsigned long data)
{
struct ccw_device *cdev;
cdev = (struct ccw_device *) data;
spin_lock_irq(cdev->ccwlock);
if (timeout_log_enabled)
ccw_timeout_log(cdev);
dev_fsm_event(cdev, DEV_EVENT_TIMEOUT);
spin_unlock_irq(cdev->ccwlock);
}
/*
* Set timeout
*/
void
ccw_device_set_timeout(struct ccw_device *cdev, int expires)
{
if (expires == 0) {
del_timer(&cdev->private->timer);
return;
}
if (timer_pending(&cdev->private->timer)) {
if (mod_timer(&cdev->private->timer, jiffies + expires))
return;
}
cdev->private->timer.function = ccw_device_timeout;
cdev->private->timer.data = (unsigned long) cdev;
cdev->private->timer.expires = jiffies + expires;
add_timer(&cdev->private->timer);
}
/*
* Cancel running i/o. This is called repeatedly since halt/clear are
* asynchronous operations. We do one try with cio_cancel, two tries
* with cio_halt, 255 tries with cio_clear. If everythings fails panic.
* Returns 0 if device now idle, -ENODEV for device not operational and
* -EBUSY if an interrupt is expected (either from halt/clear or from a
* status pending).
*/
int
ccw_device_cancel_halt_clear(struct ccw_device *cdev)
{
struct subchannel *sch;
int ret;
sch = to_subchannel(cdev->dev.parent);
if (cio_update_schib(sch))
return -ENODEV;
if (!sch->schib.pmcw.ena)
/* Not operational -> done. */
return 0;
/* Stage 1: cancel io. */
if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_HALT_PEND) &&
!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
if (!scsw_is_tm(&sch->schib.scsw)) {
ret = cio_cancel(sch);
if (ret != -EINVAL)
return ret;
}
/* cancel io unsuccessful or not applicable (transport mode).
* Continue with asynchronous instructions. */
cdev->private->iretry = 3; /* 3 halt retries. */
}
if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
/* Stage 2: halt io. */
if (cdev->private->iretry) {
cdev->private->iretry--;
ret = cio_halt(sch);
if (ret != -EBUSY)
return (ret == 0) ? -EBUSY : ret;
}
/* halt io unsuccessful. */
cdev->private->iretry = 255; /* 255 clear retries. */
}
/* Stage 3: clear io. */
if (cdev->private->iretry) {
cdev->private->iretry--;
ret = cio_clear (sch);
return (ret == 0) ? -EBUSY : ret;
}
panic("Can't stop i/o on subchannel.\n");
}
void ccw_device_update_sense_data(struct ccw_device *cdev)
{
memset(&cdev->id, 0, sizeof(cdev->id));
cdev->id.cu_type = cdev->private->senseid.cu_type;
cdev->id.cu_model = cdev->private->senseid.cu_model;
cdev->id.dev_type = cdev->private->senseid.dev_type;
cdev->id.dev_model = cdev->private->senseid.dev_model;
}
int ccw_device_test_sense_data(struct ccw_device *cdev)
{
return cdev->id.cu_type == cdev->private->senseid.cu_type &&
cdev->id.cu_model == cdev->private->senseid.cu_model &&
cdev->id.dev_type == cdev->private->senseid.dev_type &&
cdev->id.dev_model == cdev->private->senseid.dev_model;
}
/*
* The machine won't give us any notification by machine check if a chpid has
* been varied online on the SE so we have to find out by magic (i. e. driving
* the channel subsystem to device selection and updating our path masks).
*/
static void
__recover_lost_chpids(struct subchannel *sch, int old_lpm)
{
int mask, i;
struct chp_id chpid;
chp_id_init(&chpid);
for (i = 0; i<8; i++) {
mask = 0x80 >> i;
if (!(sch->lpm & mask))
continue;
if (old_lpm & mask)
continue;
chpid.id = sch->schib.pmcw.chpid[i];
if (!chp_is_registered(chpid))
css_schedule_eval_all();
}
}
/*
* Stop device recognition.
*/
static void
ccw_device_recog_done(struct ccw_device *cdev, int state)
{
struct subchannel *sch;
int old_lpm;
sch = to_subchannel(cdev->dev.parent);
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;
/* Check since device may again have become not operational. */
if (cio_update_schib(sch))
state = DEV_STATE_NOT_OPER;
else
sch->lpm = sch->schib.pmcw.pam & sch->opm;
if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
/* Force reprobe on all chpids. */
old_lpm = 0;
if (sch->lpm != old_lpm)
__recover_lost_chpids(sch, old_lpm);
if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID &&
(state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) {
cdev->private->flags.recog_done = 1;
cdev->private->state = DEV_STATE_DISCONNECTED;
wake_up(&cdev->private->wait_q);
return;
}
if (cdev->private->flags.resuming) {
cdev->private->state = state;
cdev->private->flags.recog_done = 1;
wake_up(&cdev->private->wait_q);
return;
}
switch (state) {
case DEV_STATE_NOT_OPER:
CIO_MSG_EVENT(2, "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->online) {
ccw_device_update_sense_data(cdev);
/* Issue device info message. */
CIO_MSG_EVENT(4, "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;
}
cdev->private->state = DEV_STATE_OFFLINE;
cdev->private->flags.recog_done = 1;
if (ccw_device_test_sense_data(cdev)) {
cdev->private->flags.donotify = 1;
ccw_device_online(cdev);
wake_up(&cdev->private->wait_q);
} else {
ccw_device_update_sense_data(cdev);
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_do_unbind_bind);
queue_work(ccw_device_work, &cdev->private->kick_work);
}
return;
case DEV_STATE_BOXED:
CIO_MSG_EVENT(0, "SenseID : boxed device %04x on "
" subchannel 0.%x.%04x\n",
cdev->private->dev_id.devno,
sch->schid.ssid, sch->schid.sch_no);
if (cdev->id.cu_type != 0) { /* device was recognized before */
cdev->private->flags.recog_done = 1;
cdev->private->state = DEV_STATE_BOXED;
wake_up(&cdev->private->wait_q);
return;
}
break;
}
cdev->private->state = state;
io_subchannel_recog_done(cdev);
wake_up(&cdev->private->wait_q);
}
/*
* Function called from device_id.c after sense id has completed.
*/
void
ccw_device_sense_id_done(struct ccw_device *cdev, int err)
{
switch (err) {
case 0:
ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
break;
case -ETIME: /* Sense id stopped by timeout. */
ccw_device_recog_done(cdev, DEV_STATE_BOXED);
break;
default:
ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
break;
}
}
int ccw_device_notify(struct ccw_device *cdev, int event)
{
if (!cdev->drv)
return 0;
if (!cdev->online)
return 0;
CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
event);
return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
}
static void cmf_reenable_delayed(struct work_struct *work)
{
struct ccw_device_private *priv;
struct ccw_device *cdev;
priv = container_of(work, struct ccw_device_private, kick_work);
cdev = priv->cdev;
cmf_reenable(cdev);
}
static void ccw_device_oper_notify(struct ccw_device *cdev)
{
if (ccw_device_notify(cdev, CIO_OPER)) {
/* Reenable channel measurements, if needed. */
PREPARE_WORK(&cdev->private->kick_work, cmf_reenable_delayed);
queue_work(ccw_device_work, &cdev->private->kick_work);
return;
}
/* Driver doesn't want device back. */
ccw_device_set_notoper(cdev);
PREPARE_WORK(&cdev->private->kick_work, ccw_device_do_unbind_bind);
queue_work(ccw_device_work, &cdev->private->kick_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_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
cdev->private->dev_id.devno, sch->schid.sch_no);
if (cdev->online && !ccw_device_notify(cdev, CIO_BOXED))
ccw_device_schedule_sch_unregister(cdev);
cdev->private->flags.donotify = 0;
}
if (state == DEV_STATE_NOT_OPER) {
CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
cdev->private->dev_id.devno, sch->schid.sch_no);
if (!ccw_device_notify(cdev, CIO_GONE))
ccw_device_schedule_sch_unregister(cdev);
cdev->private->flags.donotify = 0;
}
if (cdev->private->flags.donotify) {
cdev->private->flags.donotify = 0;
ccw_device_oper_notify(cdev);
}
wake_up(&cdev->private->wait_q);
}
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],
&channel_subsystems[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;
sch = to_subchannel(cdev->dev.parent);
ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
if (ret != 0)
/* Couldn't enable the subchannel for i/o. Sick device. */
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);
}
}
void
ccw_device_verify_done(struct ccw_device *cdev, int err)
{
struct subchannel *sch;
sch = to_subchannel(cdev->dev.parent);
/* Update schib - pom may have changed. */
if (cio_update_schib(sch)) {
cdev->private->flags.donotify = 0;
ccw_device_done(cdev, DEV_STATE_NOT_OPER);
return;
}
/* 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.cmd.cc = 1;
cdev->private->irb.scsw.cmd.fctl = SCSW_FCTL_START_FUNC;
cdev->private->irb.scsw.cmd.actl = SCSW_ACTL_START_PEND;
cdev->private->irb.scsw.cmd.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) {
ccw_device_set_timeout(cdev, 0);
dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
} 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);
ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
if (ret != 0) {
/* Couldn't enable the subchannel for i/o. Sick device. */
if (ret == -ENODEV)
dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
return ret;
}
/* 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;
dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
ccw_device_done(cdev, DEV_STATE_NOT_OPER);
break;
}
}
/*
* Shutdown device.
*/
int
ccw_device_offline(struct ccw_device *cdev)
{
struct subchannel *sch;
/* Allow ccw_device_offline while disconnected. */
if (cdev->private->state == DEV_STATE_DISCONNECTED ||
cdev->private->state == DEV_STATE_NOT_OPER) {
cdev->private->flags.donotify = 0;
ccw_device_done(cdev, DEV_STATE_NOT_OPER);
return 0;
}
if (ccw_device_is_orphan(cdev)) {
ccw_device_done(cdev, DEV_STATE_OFFLINE);
return 0;
}
sch = to_subchannel(cdev->dev.parent);
if (cio_update_schib(sch))
return -ENODEV;
if (scsw_actl(&sch->schib.scsw) != 0)
return -EBUSY;
if (cdev->private->state != DEV_STATE_ONLINE)
return -EINVAL;
/* Are we doing path grouping? */
if (!cdev->private->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 in non-special state.
*/
static void ccw_device_generic_notoper(struct ccw_device *cdev,
enum dev_event dev_event)
{
struct subchannel *sch;
ccw_device_set_notoper(cdev);
sch = to_subchannel(cdev->dev.parent);
css_schedule_eval(sch->schid);
}
/*
* Handle path verification event in offline state.
*/
static void ccw_device_offline_verify(struct ccw_device *cdev,
enum dev_event dev_event)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
css_schedule_eval(sch->schid);
}
/*
* Handle path verification event.
*/
static void
ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
{
struct subchannel *sch;
if (cdev->private->state == DEV_STATE_W4SENSE) {
cdev->private->flags.doverify = 1;
return;
}
sch = to_subchannel(cdev->dev.parent);
/*
* Since we might not just be coming from an interrupt from the
* subchannel we have to update the schib.
*/
if (cio_update_schib(sch)) {
ccw_device_verify_done(cdev, -ENODEV);
return;
}
if (scsw_actl(&sch->schib.scsw) != 0 ||
(scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
(scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) {
/*
* No final status yet or final status not yet delivered
* to the device driver. Can't do path 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;
int is_cmd;
irb = (struct irb *) __LC_IRB;
is_cmd = !scsw_is_tm(&irb->scsw);
/* Check for unsolicited interrupt. */
if (!scsw_is_solicited(&irb->scsw)) {
if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
!irb->esw.esw0.erw.cons) {
/* Unit check but no sense data. Need basic sense. */
if (ccw_device_do_sense(cdev, irb) != 0)
goto call_handler_unsol;
memcpy(&cdev->private->irb, irb, sizeof(struct irb));
cdev->private->state = DEV_STATE_W4SENSE;
cdev->private->intparm = 0;
return;
}
call_handler_unsol:
if (cdev->handler)
cdev->handler (cdev, 0, irb);
if (cdev->private->flags.doverify)
ccw_device_online_verify(cdev, 0);
return;
}
/* Accumulate status and find out if a basic sense is needed. */
ccw_device_accumulate_irb(cdev, irb);
if (is_cmd && cdev->private->flags.dosense) {
if (ccw_device_do_sense(cdev, irb) == 0) {
cdev->private->state = DEV_STATE_W4SENSE;
}
return;
}
/* Call the handler. */
if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
/* Start delayed path verification. */
ccw_device_online_verify(cdev, 0);
}
/*
* Got an timeout in online state.
*/
static void
ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
{
int ret;
ccw_device_set_timeout(cdev, 0);
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)
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 (scsw_stctl(&irb->scsw) ==
(SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
if (scsw_cc(&irb->scsw) == 1)
/* Basic sense hasn't started. Try again. */
ccw_device_do_sense(cdev, irb);
else {
CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
"interrupt during w4sense...\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
if (cdev->handler)
cdev->handler (cdev, 0, irb);
}
return;
}
/*
* Check if a halt or clear has been issued in the meanwhile. If yes,
* only deliver the halt/clear interrupt to the device driver as if it
* had killed the original request.
*/
if (scsw_fctl(&irb->scsw) &
(SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
/* 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;
/* In case sensing interfered with setting the device online */
wake_up(&cdev->private->wait_q);
/* Call the handler. */
if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
/* Start delayed path verification. */
ccw_device_online_verify(cdev, 0);
}
static void
ccw_device_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 ccw_device_kill_io(struct ccw_device *cdev)
{
int ret;
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 ((scsw_stctl(&irb->scsw) ==
(SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) &&
(!scsw_cc(&irb->scsw)))
/* 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, (u32)(addr_t)sch) != 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 ccw_device_trigger_reprobe(struct ccw_device *cdev)
{
struct subchannel *sch;
if (cdev->private->state != DEV_STATE_DISCONNECTED)
return;
sch = to_subchannel(cdev->dev.parent);
/* Update some values. */
if (cio_update_schib(sch))
return;
/*
* The pim, pam, pom values may not be accurate, but they are the best
* we have before performing device selection :/
*/
sch->lpm = sch->schib.pmcw.pam & sch->opm;
/*
* Use the initial configuration since we can't be shure that the old
* paths are valid.
*/
io_subchannel_init_config(sch);
if (cio_commit_config(sch))
return;
/* We should also udate ssd info, but this has to wait. */
/* Check if this is another device which appeared on the same sch. */
if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_move_to_orphanage);
queue_work(slow_path_wq, &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 - should not happen, but we try to disable again.
*/
cio_disable_subchannel(sch);
}
static void
ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
{
retry_set_schib(cdev);
cdev->private->state = DEV_STATE_ONLINE;
dev_fsm_event(cdev, dev_event);
}
static void ccw_device_update_cmfblock(struct ccw_device *cdev,
enum dev_event dev_event)
{
cmf_retry_copy_block(cdev);
cdev->private->state = DEV_STATE_ONLINE;
dev_fsm_event(cdev, dev_event);
}
static void
ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
{
ccw_device_set_timeout(cdev, 0);
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, "Internal state [%i][%i] not handled for device "
"0.%x.%04x\n", cdev->private->state, dev_event,
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
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_generic_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_generic_notoper,
[DEV_EVENT_INTERRUPT] = ccw_device_offline_irq,
[DEV_EVENT_TIMEOUT] = ccw_device_nop,
[DEV_EVENT_VERIFY] = ccw_device_offline_verify,
},
[DEV_STATE_VERIFY] = {
[DEV_EVENT_NOTOPER] = ccw_device_generic_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_generic_notoper,
[DEV_EVENT_INTERRUPT] = ccw_device_irq,
[DEV_EVENT_TIMEOUT] = ccw_device_online_timeout,
[DEV_EVENT_VERIFY] = ccw_device_online_verify,
},
[DEV_STATE_W4SENSE] = {
[DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
[DEV_EVENT_INTERRUPT] = ccw_device_w4sense,
[DEV_EVENT_TIMEOUT] = ccw_device_nop,
[DEV_EVENT_VERIFY] = ccw_device_online_verify,
},
[DEV_STATE_DISBAND_PGID] = {
[DEV_EVENT_NOTOPER] = ccw_device_generic_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_generic_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_generic_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_generic_notoper,
[DEV_EVENT_INTERRUPT] = ccw_device_killing_irq,
[DEV_EVENT_TIMEOUT] = ccw_device_killing_timeout,
[DEV_EVENT_VERIFY] = ccw_device_nop, //FIXME
},
[DEV_STATE_QUIESCE] = {
[DEV_EVENT_NOTOPER] = ccw_device_quiesce_done,
[DEV_EVENT_INTERRUPT] = ccw_device_quiesce_done,
[DEV_EVENT_TIMEOUT] = ccw_device_quiesce_timeout,
[DEV_EVENT_VERIFY] = ccw_device_nop,
},
/* special states for devices gone not operational */
[DEV_STATE_DISCONNECTED] = {
[DEV_EVENT_NOTOPER] = ccw_device_nop,
[DEV_EVENT_INTERRUPT] = ccw_device_start_id,
[DEV_EVENT_TIMEOUT] = ccw_device_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,
},
};
EXPORT_SYMBOL_GPL(ccw_device_set_timeout);