// SPDX-License-Identifier: GPL-2.0
/*
* finite state machine for device handling
*
* Copyright IBM Corp. 2002, 2008
* Author(s): Cornelia Huck ([email protected])
* Martin Schwidefsky ([email protected])
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/io.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 %lx, "
"device information:\n", get_tod_clock());
printk(KERN_WARNING "cio: orb:\n");
print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
orb, sizeof(*orb), 0);
printk(KERN_WARNING "cio: ccw device bus id: %s\n",
dev_name(&cdev->dev));
printk(KERN_WARNING "cio: subchannel bus id: %s\n",
dev_name(&sch->dev));
printk(KERN_WARNING "cio: subchannel lpm: %02x, opm: %02x, "
"vpm: %02x\n", sch->lpm, sch->opm, sch->vpm);
if (orb->tm.b) {
printk(KERN_WARNING "cio: orb indicates transport mode\n");
printk(KERN_WARNING "cio: last tcw:\n");
print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
dma32_to_virt(orb->tm.tcw),
sizeof(struct tcw), 0);
} else {
printk(KERN_WARNING "cio: orb indicates command mode\n");
if (dma32_to_virt(orb->cmd.cpa) ==
&private->dma_area->sense_ccw ||
dma32_to_virt(orb->cmd.cpa) ==
cdev->private->dma_area->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,
dma32_to_virt(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.
*/
void
ccw_device_timeout(struct timer_list *t)
{
struct ccw_device_private *priv = from_timer(priv, t, timer);
struct ccw_device *cdev = priv->cdev;
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);
else
mod_timer(&cdev->private->timer, jiffies + expires);
}
int
ccw_device_cancel_halt_clear(struct ccw_device *cdev)
{
struct subchannel *sch;
int ret;
sch = to_subchannel(cdev->dev.parent);
ret = cio_cancel_halt_clear(sch, &cdev->private->iretry);
if (ret == -EIO)
CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
return ret;
}
void ccw_device_update_sense_data(struct ccw_device *cdev)
{
memset(&cdev->id, 0, sizeof(cdev->id));
cdev->id.cu_type = cdev->private->dma_area->senseid.cu_type;
cdev->id.cu_model = cdev->private->dma_area->senseid.cu_model;
cdev->id.dev_type = cdev->private->dma_area->senseid.dev_type;
cdev->id.dev_model = cdev->private->dma_area->senseid.dev_model;
}
int ccw_device_test_sense_data(struct ccw_device *cdev)
{
return cdev->id.cu_type ==
cdev->private->dma_area->senseid.cu_type &&
cdev->id.cu_model ==
cdev->private->dma_area->senseid.cu_model &&
cdev->id.dev_type ==
cdev->private->dma_area->senseid.dev_type &&
cdev->id.dev_model ==
cdev->private->dma_area->senseid.dev_model;
}
/*
* The machine won't give us any notification by machine check if a chpid has
* been varied online on the SE so we have to find out by magic (i. e. driving
* the channel subsystem to device selection and updating our path masks).
*/
static void
__recover_lost_chpids(struct subchannel *sch, int old_lpm)
{
int mask, i;
struct chp_id chpid;
chp_id_init(&chpid);
for (i = 0; i<8; i++) {
mask = 0x80 >> i;
if (!(sch->lpm & mask))
continue;
if (old_lpm & mask)
continue;
chpid.id = sch->schib.pmcw.chpid[i];
if (!chp_is_registered(chpid))
css_schedule_eval_all();
}
}
/*
* Stop device recognition.
*/
static void
ccw_device_recog_done(struct ccw_device *cdev, int state)
{
struct subchannel *sch;
int old_lpm;
sch = to_subchannel(cdev->dev.parent);
if (cio_disable_subchannel(sch))
state = DEV_STATE_NOT_OPER;
/*
* Now that we tried recognition, we have performed device selection
* through ssch() and the path information is up to date.
*/
old_lpm = sch->lpm;
/* Check since device may again have become not operational. */
if (cio_update_schib(sch))
state = DEV_STATE_NOT_OPER;
else
sch->lpm = sch->schib.pmcw.pam & sch->opm;
if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
/* Force reprobe on all chpids. */
old_lpm = 0;
if (sch->lpm != old_lpm)
__recover_lost_chpids(sch, old_lpm);
if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID &&
(state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) {
cdev->private->flags.recog_done = 1;
cdev->private->state = DEV_STATE_DISCONNECTED;
wake_up(&cdev->private->wait_q);
return;
}
switch (state) {
case DEV_STATE_NOT_OPER:
break;
case DEV_STATE_OFFLINE:
if (!cdev->online) {
ccw_device_update_sense_data(cdev);
break;
}
cdev->private->state = DEV_STATE_OFFLINE;
cdev->private->flags.recog_done = 1;
if (ccw_device_test_sense_data(cdev)) {
cdev->private->flags.donotify = 1;
ccw_device_online(cdev);
wake_up(&cdev->private->wait_q);
} else {
ccw_device_update_sense_data(cdev);
ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
}
return;
case DEV_STATE_BOXED:
if (cdev->id.cu_type != 0) { /* device was recognized before */
cdev->private->flags.recog_done = 1;
cdev->private->state = DEV_STATE_BOXED;
wake_up(&cdev->private->wait_q);
return;
}
break;
}
cdev->private->state = state;
io_subchannel_recog_done(cdev);
wake_up(&cdev->private->wait_q);
}
/*
* Function called from device_id.c after sense id has completed.
*/
void
ccw_device_sense_id_done(struct ccw_device *cdev, int err)
{
switch (err) {
case 0:
ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
break;
case -ETIME: /* Sense id stopped by timeout. */
ccw_device_recog_done(cdev, DEV_STATE_BOXED);
break;
default:
ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
break;
}
}
/**
* ccw_device_notify() - inform the device's driver about an event
* @cdev: device for which an event occurred
* @event: event that occurred
*
* Returns:
* -%EINVAL if the device is offline or has no driver.
* -%EOPNOTSUPP if the device's driver has no notifier registered.
* %NOTIFY_OK if the driver wants to keep the device.
* %NOTIFY_BAD if the driver doesn't want to keep the device.
*/
int ccw_device_notify(struct ccw_device *cdev, int event)
{
int ret = -EINVAL;
if (!cdev->drv)
goto out;
if (!cdev->online)
goto out;
CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
event);
if (!cdev->drv->notify) {
ret = -EOPNOTSUPP;
goto out;
}
if (cdev->drv->notify(cdev, event))
ret = NOTIFY_OK;
else
ret = NOTIFY_BAD;
out:
return ret;
}
static void ccw_device_oper_notify(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) {
/* Re-enable channel measurements, if needed. */
ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
/* Save indication for new paths. */
cdev->private->path_new_mask = sch->vpm;
return;
}
/* Driver doesn't want device back. */
ccw_device_set_notoper(cdev);
ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
}
/*
* Finished with online/offline processing.
*/
static void
ccw_device_done(struct ccw_device *cdev, int state)
{
struct subchannel *sch;
sch = to_subchannel(cdev->dev.parent);
ccw_device_set_timeout(cdev, 0);
if (state != DEV_STATE_ONLINE)
cio_disable_subchannel(sch);
/* Reset device status. */
memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
cdev->private->state = state;
switch (state) {
case DEV_STATE_BOXED:
CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
cdev->private->dev_id.devno, sch->schid.sch_no);
if (cdev->online &&
ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK)
ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
cdev->private->flags.donotify = 0;
break;
case DEV_STATE_NOT_OPER:
CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
cdev->private->dev_id.devno, sch->schid.sch_no);
if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
else
ccw_device_set_disconnected(cdev);
cdev->private->flags.donotify = 0;
break;
case DEV_STATE_DISCONNECTED:
CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
"%04x\n", cdev->private->dev_id.devno,
sch->schid.sch_no);
if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) {
cdev->private->state = DEV_STATE_NOT_OPER;
ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
} else
ccw_device_set_disconnected(cdev);
cdev->private->flags.donotify = 0;
break;
default:
break;
}
if (cdev->private->flags.donotify) {
cdev->private->flags.donotify = 0;
ccw_device_oper_notify(cdev);
}
wake_up(&cdev->private->wait_q);
}
/*
* Start device recognition.
*/
void ccw_device_recognition(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
/*
* We used to start here with a sense pgid to find out whether a device
* is locked by someone else. Unfortunately, the sense pgid command
* code has other meanings on devices predating the path grouping
* algorithm, so we start with sense id and box the device after an
* timeout (or if sense pgid during path verification detects the device
* is locked, as may happen on newer devices).
*/
cdev->private->flags.recog_done = 0;
cdev->private->state = DEV_STATE_SENSE_ID;
if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch))) {
ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
return;
}
ccw_device_sense_id_start(cdev);
}
/*
* Handle events for states that use the ccw request infrastructure.
*/
static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
{
switch (e) {
case DEV_EVENT_NOTOPER:
ccw_request_notoper(cdev);
break;
case DEV_EVENT_INTERRUPT:
ccw_request_handler(cdev);
break;
case DEV_EVENT_TIMEOUT:
ccw_request_timeout(cdev);
break;
default:
break;
}
}
static void ccw_device_report_path_events(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
int path_event[8];
int chp, mask;
for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) {
path_event[chp] = PE_NONE;
if (mask & cdev->private->path_gone_mask & ~(sch->vpm))
path_event[chp] |= PE_PATH_GONE;
if (mask & cdev->private->path_new_mask & sch->vpm)
path_event[chp] |= PE_PATH_AVAILABLE;
if (mask & cdev->private->pgid_reset_mask & sch->vpm)
path_event[chp] |= PE_PATHGROUP_ESTABLISHED;
}
if (cdev->online && cdev->drv->path_event)
cdev->drv->path_event(cdev, path_event);
}
static void ccw_device_reset_path_events(struct ccw_device *cdev)
{
cdev->private->path_gone_mask = 0;
cdev->private->path_new_mask = 0;
cdev->private->pgid_reset_mask = 0;
}
static void create_fake_irb(struct irb *irb, int type)
{
memset(irb, 0, sizeof(*irb));
if (type == FAKE_CMD_IRB) {
struct cmd_scsw *scsw = &irb->scsw.cmd;
scsw->cc = 1;
scsw->fctl = SCSW_FCTL_START_FUNC;
scsw->actl = SCSW_ACTL_START_PEND;
scsw->stctl = SCSW_STCTL_STATUS_PEND;
} else if (type == FAKE_TM_IRB) {
struct tm_scsw *scsw = &irb->scsw.tm;
scsw->x = 1;
scsw->cc = 1;
scsw->fctl = SCSW_FCTL_START_FUNC;
scsw->actl = SCSW_ACTL_START_PEND;
scsw->stctl = SCSW_STCTL_STATUS_PEND;
}
}
static void ccw_device_handle_broken_paths(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
u8 broken_paths = (sch->schib.pmcw.pam & sch->opm) ^ sch->vpm;
if (broken_paths && (cdev->private->path_broken_mask != broken_paths))
ccw_device_schedule_recovery();
cdev->private->path_broken_mask = broken_paths;
}
void ccw_device_verify_done(struct ccw_device *cdev, int err)
{
struct subchannel *sch;
sch = to_subchannel(cdev->dev.parent);
/* Update schib - pom may have changed. */
if (cio_update_schib(sch)) {
err = -ENODEV;
goto callback;
}
/* Update lpm with verified path mask. */
sch->lpm = sch->vpm;
/* Repeat path verification? */
if (cdev->private->flags.doverify) {
ccw_device_verify_start(cdev);
return;
}
callback:
switch (err) {
case 0:
ccw_device_done(cdev, DEV_STATE_ONLINE);
/* Deliver fake irb to device driver, if needed. */
if (cdev->private->flags.fake_irb) {
CIO_MSG_EVENT(2, "fakeirb: deliver device 0.%x.%04x intparm %lx type=%d\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno,
cdev->private->intparm,
cdev->private->flags.fake_irb);
create_fake_irb(&cdev->private->dma_area->irb,
cdev->private->flags.fake_irb);
cdev->private->flags.fake_irb = 0;
if (cdev->handler)
cdev->handler(cdev, cdev->private->intparm,
&cdev->private->dma_area->irb);
memset(&cdev->private->dma_area->irb, 0,
sizeof(struct irb));
}
ccw_device_report_path_events(cdev);
ccw_device_handle_broken_paths(cdev);
break;
case -ETIME:
case -EUSERS:
/* Reset oper notify indication after verify error. */
cdev->private->flags.donotify = 0;
ccw_device_done(cdev, DEV_STATE_BOXED);
break;
case -EACCES:
/* Reset oper notify indication after verify error. */
cdev->private->flags.donotify = 0;
ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
break;
default:
/* Reset oper notify indication after verify error. */
cdev->private->flags.donotify = 0;
ccw_device_done(cdev, DEV_STATE_NOT_OPER);
break;
}
ccw_device_reset_path_events(cdev);
}
/*
* Get device online.
*/
int
ccw_device_online(struct ccw_device *cdev)
{
struct subchannel *sch;
int ret;
if ((cdev->private->state != DEV_STATE_OFFLINE) &&
(cdev->private->state != DEV_STATE_BOXED))
return -EINVAL;
sch = to_subchannel(cdev->dev.parent);
ret = cio_enable_subchannel(sch, (u32)virt_to_phys(sch));
if (ret != 0) {
/* Couldn't enable the subchannel for i/o. Sick device. */
if (ret == -ENODEV)
dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
return ret;
}
/* Start initial path verification. */
cdev->private->state = DEV_STATE_VERIFY;
ccw_device_verify_start(cdev);
return 0;
}
void
ccw_device_disband_done(struct ccw_device *cdev, int err)
{
switch (err) {
case 0:
ccw_device_done(cdev, DEV_STATE_OFFLINE);
break;
case -ETIME:
ccw_device_done(cdev, DEV_STATE_BOXED);
break;
default:
cdev->private->flags.donotify = 0;
ccw_device_done(cdev, DEV_STATE_NOT_OPER);
break;
}
}
/*
* Shutdown device.
*/
int
ccw_device_offline(struct ccw_device *cdev)
{
struct subchannel *sch;
/* Allow ccw_device_offline while disconnected. */
if (cdev->private->state == DEV_STATE_DISCONNECTED ||
cdev->private->state == DEV_STATE_NOT_OPER) {
cdev->private->flags.donotify = 0;
ccw_device_done(cdev, DEV_STATE_NOT_OPER);
return 0;
}
if (cdev->private->state == DEV_STATE_BOXED) {
ccw_device_done(cdev, DEV_STATE_BOXED);
return 0;
}
if (ccw_device_is_orphan(cdev)) {
ccw_device_done(cdev, DEV_STATE_OFFLINE);
return 0;
}
sch = to_subchannel(cdev->dev.parent);
if (cio_update_schib(sch))
return -ENODEV;
if (scsw_actl(&sch->schib.scsw) != 0)
return -EBUSY;
if (cdev->private->state != DEV_STATE_ONLINE)
return -EINVAL;
/* Are we doing path grouping? */
if (!cdev->private->flags.pgroup) {
/* No, set state offline immediately. */
ccw_device_done(cdev, DEV_STATE_OFFLINE);
return 0;
}
/* Start Set Path Group commands. */
cdev->private->state = DEV_STATE_DISBAND_PGID;
ccw_device_disband_start(cdev);
return 0;
}
/*
* Handle not operational event in non-special state.
*/
static void ccw_device_generic_notoper(struct ccw_device *cdev,
enum dev_event dev_event)
{
if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
else
ccw_device_set_disconnected(cdev);
}
/*
* Handle path verification event in offline state.
*/
static void ccw_device_offline_verify(struct ccw_device *cdev,
enum dev_event dev_event)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
css_schedule_eval(sch->schid);
}
/*
* Handle path verification event.
*/
static void
ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
{
struct subchannel *sch;
if (cdev->private->state == DEV_STATE_W4SENSE) {
cdev->private->flags.doverify = 1;
return;
}
sch = to_subchannel(cdev->dev.parent);
/*
* Since we might not just be coming from an interrupt from the
* subchannel we have to update the schib.
*/
if (cio_update_schib(sch)) {
ccw_device_verify_done(cdev, -ENODEV);
return;
}
if (scsw_actl(&sch->schib.scsw) != 0 ||
(scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
(scsw_stctl(&cdev->private->dma_area->irb.scsw) &
SCSW_STCTL_STATUS_PEND)) {
/*
* No final status yet or final status not yet delivered
* to the device driver. Can't do path verification now,
* delay until final status was delivered.
*/
cdev->private->flags.doverify = 1;
return;
}
/* Device is idle, we can do the path verification. */
cdev->private->state = DEV_STATE_VERIFY;
ccw_device_verify_start(cdev);
}
/*
* Handle path verification event in boxed state.
*/
static void ccw_device_boxed_verify(struct ccw_device *cdev,
enum dev_event dev_event)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
if (cdev->online) {
if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch)))
ccw_device_done(cdev, DEV_STATE_NOT_OPER);
else
ccw_device_online_verify(cdev, dev_event);
} else
css_schedule_eval(sch->schid);
}
/*
* Pass interrupt to device driver.
*/
static int ccw_device_call_handler(struct ccw_device *cdev)
{
unsigned int stctl;
int ending_status;
/*
* we allow for the device action handler if .
* - we received ending status
* - the action handler requested to see all interrupts
* - we received an intermediate status
* - fast notification was requested (primary status)
* - unsolicited interrupts
*/
stctl = scsw_stctl(&cdev->private->dma_area->irb.scsw);
ending_status = (stctl & SCSW_STCTL_SEC_STATUS) ||
(stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) ||
(stctl == SCSW_STCTL_STATUS_PEND);
if (!ending_status &&
!cdev->private->options.repall &&
!(stctl & SCSW_STCTL_INTER_STATUS) &&
!(cdev->private->options.fast &&
(stctl & SCSW_STCTL_PRIM_STATUS)))
return 0;
if (ending_status)
ccw_device_set_timeout(cdev, 0);
if (cdev->handler)
cdev->handler(cdev, cdev->private->intparm,
&cdev->private->dma_area->irb);
memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
return 1;
}
/*
* Got an interrupt for a normal io (state online).
*/
static void
ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
{
struct irb *irb;
int is_cmd;
irb = this_cpu_ptr(&cio_irb);
is_cmd = !scsw_is_tm(&irb->scsw);
/* Check for unsolicited interrupt. */
if (!scsw_is_solicited(&irb->scsw)) {
if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
!irb->esw.esw0.erw.cons) {
/* Unit check but no sense data. Need basic sense. */
if (ccw_device_do_sense(cdev, irb) != 0)
goto call_handler_unsol;
memcpy(&cdev->private->dma_area->irb, irb,
sizeof(struct irb));
cdev->private->state = DEV_STATE_W4SENSE;
cdev->private->intparm = 0;
return;
}
call_handler_unsol:
if (cdev->handler)
cdev->handler (cdev, 0, irb);
if (cdev->private->flags.doverify)
ccw_device_online_verify(cdev, 0);
return;
}
/* Accumulate status and find out if a basic sense is needed. */
ccw_device_accumulate_irb(cdev, irb);
if (is_cmd && cdev->private->flags.dosense) {
if (ccw_device_do_sense(cdev, irb) == 0) {
cdev->private->state = DEV_STATE_W4SENSE;
}
return;
}
/* Call the handler. */
if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
/* Start delayed path verification. */
ccw_device_online_verify(cdev, 0);
}
/*
* Got an timeout in online state.
*/
static void
ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
{
int ret;
ccw_device_set_timeout(cdev, 0);
cdev->private->iretry = 255;
cdev->private->async_kill_io_rc = -ETIMEDOUT;
ret = ccw_device_cancel_halt_clear(cdev);
if (ret == -EBUSY) {
ccw_device_set_timeout(cdev, 3*HZ);
cdev->private->state = DEV_STATE_TIMEOUT_KILL;
return;
}
if (ret)
dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
else if (cdev->handler)
cdev->handler(cdev, cdev->private->intparm,
ERR_PTR(-ETIMEDOUT));
}
/*
* Got an interrupt for a basic sense.
*/
static void
ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
{
struct irb *irb;
irb = this_cpu_ptr(&cio_irb);
/* Check for unsolicited interrupt. */
if (scsw_stctl(&irb->scsw) ==
(SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
if (scsw_cc(&irb->scsw) == 1)
/* Basic sense hasn't started. Try again. */
ccw_device_do_sense(cdev, irb);
else {
CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
"interrupt during w4sense...\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
if (cdev->handler)
cdev->handler (cdev, 0, irb);
}
return;
}
/*
* Check if a halt or clear has been issued in the meanwhile. If yes,
* only deliver the halt/clear interrupt to the device driver as if it
* had killed the original request.
*/
if (scsw_fctl(&irb->scsw) &
(SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
cdev->private->flags.dosense = 0;
memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
ccw_device_accumulate_irb(cdev, irb);
goto call_handler;
}
/* Add basic sense info to irb. */
ccw_device_accumulate_basic_sense(cdev, irb);
if (cdev->private->flags.dosense) {
/* Another basic sense is needed. */
ccw_device_do_sense(cdev, irb);
return;
}
call_handler:
cdev->private->state = DEV_STATE_ONLINE;
/* In case sensing interfered with setting the device online */
wake_up(&cdev->private->wait_q);
/* Call the handler. */
if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
/* Start delayed path verification. */
ccw_device_online_verify(cdev, 0);
}
static void
ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
{
ccw_device_set_timeout(cdev, 0);
/* Start delayed path verification. */
ccw_device_online_verify(cdev, 0);
/* OK, i/o is dead now. Call interrupt handler. */
if (cdev->handler)
cdev->handler(cdev, cdev->private->intparm,
ERR_PTR(cdev->private->async_kill_io_rc));
}
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(cdev->private->async_kill_io_rc));
}
void ccw_device_kill_io(struct ccw_device *cdev)
{
int ret;
ccw_device_set_timeout(cdev, 0);
cdev->private->iretry = 255;
cdev->private->async_kill_io_rc = -EIO;
ret = ccw_device_cancel_halt_clear(cdev);
if (ret == -EBUSY) {
ccw_device_set_timeout(cdev, 3*HZ);
cdev->private->state = DEV_STATE_TIMEOUT_KILL;
return;
}
/* Start delayed path verification. */
ccw_device_online_verify(cdev, 0);
if (cdev->handler)
cdev->handler(cdev, cdev->private->intparm,
ERR_PTR(-EIO));
}
static void
ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
{
/* Start verification after current task finished. */
cdev->private->flags.doverify = 1;
}
static void
ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
{
struct subchannel *sch;
sch = to_subchannel(cdev->dev.parent);
if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch)) != 0)
/* Couldn't enable the subchannel for i/o. Sick device. */
return;
cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
ccw_device_sense_id_start(cdev);
}
void ccw_device_trigger_reprobe(struct ccw_device *cdev)
{
struct subchannel *sch;
if (cdev->private->state != DEV_STATE_DISCONNECTED)
return;
sch = to_subchannel(cdev->dev.parent);
/* Update some values. */
if (cio_update_schib(sch))
return;
/*
* The pim, pam, pom values may not be accurate, but they are the best
* we have before performing device selection :/
*/
sch->lpm = sch->schib.pmcw.pam & sch->opm;
/*
* Use the initial configuration since we can't be sure that the old
* paths are valid.
*/
io_subchannel_init_config(sch);
if (cio_commit_config(sch))
return;
/* We should also udate ssd info, but this has to wait. */
/* Check if this is another device which appeared on the same sch. */
if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
css_schedule_eval(sch->schid);
else
ccw_device_start_id(cdev, 0);
}
static void ccw_device_disabled_irq(struct ccw_device *cdev,
enum dev_event dev_event)
{
struct subchannel *sch;
sch = to_subchannel(cdev->dev.parent);
/*
* An interrupt in a disabled state means a previous disable was not
* successful - should not happen, but we try to disable again.
*/
cio_disable_subchannel(sch);
}
static void
ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
{
retry_set_schib(cdev);
cdev->private->state = DEV_STATE_ONLINE;
dev_fsm_event(cdev, dev_event);
}
static void ccw_device_update_cmfblock(struct ccw_device *cdev,
enum dev_event dev_event)
{
cmf_retry_copy_block(cdev);
cdev->private->state = DEV_STATE_ONLINE;
dev_fsm_event(cdev, dev_event);
}
static void
ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
{
ccw_device_set_timeout(cdev, 0);
cdev->private->state = DEV_STATE_NOT_OPER;
wake_up(&cdev->private->wait_q);
}
static void
ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
{
int ret;
ret = ccw_device_cancel_halt_clear(cdev);
if (ret == -EBUSY) {
ccw_device_set_timeout(cdev, HZ/10);
} else {
cdev->private->state = DEV_STATE_NOT_OPER;
wake_up(&cdev->private->wait_q);
}
}
/*
* No operation action. This is used e.g. to ignore a timeout event in
* state offline.
*/
static void
ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
{
}
/*
* device statemachine
*/
fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
[DEV_STATE_NOT_OPER] = {
[DEV_EVENT_NOTOPER] = ccw_device_nop,
[DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq,
[DEV_EVENT_TIMEOUT] = ccw_device_nop,
[DEV_EVENT_VERIFY] = ccw_device_nop,
},
[DEV_STATE_SENSE_ID] = {
[DEV_EVENT_NOTOPER] = ccw_device_request_event,
[DEV_EVENT_INTERRUPT] = ccw_device_request_event,
[DEV_EVENT_TIMEOUT] = ccw_device_request_event,
[DEV_EVENT_VERIFY] = ccw_device_nop,
},
[DEV_STATE_OFFLINE] = {
[DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
[DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq,
[DEV_EVENT_TIMEOUT] = ccw_device_nop,
[DEV_EVENT_VERIFY] = ccw_device_offline_verify,
},
[DEV_STATE_VERIFY] = {
[DEV_EVENT_NOTOPER] = ccw_device_request_event,
[DEV_EVENT_INTERRUPT] = ccw_device_request_event,
[DEV_EVENT_TIMEOUT] = ccw_device_request_event,
[DEV_EVENT_VERIFY] = ccw_device_delay_verify,
},
[DEV_STATE_ONLINE] = {
[DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
[DEV_EVENT_INTERRUPT] = ccw_device_irq,
[DEV_EVENT_TIMEOUT] = ccw_device_online_timeout,
[DEV_EVENT_VERIFY] = ccw_device_online_verify,
},
[DEV_STATE_W4SENSE] = {
[DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
[DEV_EVENT_INTERRUPT] = ccw_device_w4sense,
[DEV_EVENT_TIMEOUT] = ccw_device_nop,
[DEV_EVENT_VERIFY] = ccw_device_online_verify,
},
[DEV_STATE_DISBAND_PGID] = {
[DEV_EVENT_NOTOPER] = ccw_device_request_event,
[DEV_EVENT_INTERRUPT] = ccw_device_request_event,
[DEV_EVENT_TIMEOUT] = ccw_device_request_event,
[DEV_EVENT_VERIFY] = ccw_device_nop,
},
[DEV_STATE_BOXED] = {
[DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
[DEV_EVENT_INTERRUPT] = ccw_device_nop,
[DEV_EVENT_TIMEOUT] = ccw_device_nop,
[DEV_EVENT_VERIFY] = ccw_device_boxed_verify,
},
/* states to wait for i/o completion before doing something */
[DEV_STATE_TIMEOUT_KILL] = {
[DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
[DEV_EVENT_INTERRUPT] = ccw_device_killing_irq,
[DEV_EVENT_TIMEOUT] = ccw_device_killing_timeout,
[DEV_EVENT_VERIFY] = ccw_device_nop, //FIXME
},
[DEV_STATE_QUIESCE] = {
[DEV_EVENT_NOTOPER] = ccw_device_quiesce_done,
[DEV_EVENT_INTERRUPT] = ccw_device_quiesce_done,
[DEV_EVENT_TIMEOUT] = ccw_device_quiesce_timeout,
[DEV_EVENT_VERIFY] = ccw_device_nop,
},
/* special states for devices gone not operational */
[DEV_STATE_DISCONNECTED] = {
[DEV_EVENT_NOTOPER] = ccw_device_nop,
[DEV_EVENT_INTERRUPT] = ccw_device_start_id,
[DEV_EVENT_TIMEOUT] = ccw_device_nop,
[DEV_EVENT_VERIFY] = ccw_device_start_id,
},
[DEV_STATE_DISCONNECTED_SENSE_ID] = {
[DEV_EVENT_NOTOPER] = ccw_device_request_event,
[DEV_EVENT_INTERRUPT] = ccw_device_request_event,
[DEV_EVENT_TIMEOUT] = ccw_device_request_event,
[DEV_EVENT_VERIFY] = ccw_device_nop,
},
[DEV_STATE_CMFCHANGE] = {
[DEV_EVENT_NOTOPER] = ccw_device_change_cmfstate,
[DEV_EVENT_INTERRUPT] = ccw_device_change_cmfstate,
[DEV_EVENT_TIMEOUT] = ccw_device_change_cmfstate,
[DEV_EVENT_VERIFY] = ccw_device_change_cmfstate,
},
[DEV_STATE_CMFUPDATE] = {
[DEV_EVENT_NOTOPER] = ccw_device_update_cmfblock,
[DEV_EVENT_INTERRUPT] = ccw_device_update_cmfblock,
[DEV_EVENT_TIMEOUT] = ccw_device_update_cmfblock,
[DEV_EVENT_VERIFY] = ccw_device_update_cmfblock,
},
[DEV_STATE_STEAL_LOCK] = {
[DEV_EVENT_NOTOPER] = ccw_device_request_event,
[DEV_EVENT_INTERRUPT] = ccw_device_request_event,
[DEV_EVENT_TIMEOUT] = ccw_device_request_event,
[DEV_EVENT_VERIFY] = ccw_device_nop,
},
};
EXPORT_SYMBOL_GPL(ccw_device_set_timeout);
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