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3ac276f8cb
linux/drivers/s390/cio/device.c
Sebastian Ott 3ac276f8cb [S390] cio: remove ccw_device init_name 
We used the init_name to set the console ccw_device's name early
at the boot stage. This patch moves the name setting (for all ccw
devices) to the point where we actually register the device. At this
time we can do dynamic allocations and therefore use dev_set_name.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11 10:29:41 +02:00

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/*
* drivers/s390/cio/device.c
* bus driver for ccw devices
*
* Copyright IBM Corp. 2002,2008
* Author(s): Arnd Bergmann (arndb@de.ibm.com)
* Cornelia Huck (cornelia.huck@de.ibm.com)
* Martin Schwidefsky (schwidefsky@de.ibm.com)
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/device.h>
#include <linux/workqueue.h>
#include <linux/timer.h>
#include <asm/ccwdev.h>
#include <asm/cio.h>
#include <asm/param.h> /* HZ */
#include <asm/cmb.h>
#include <asm/isc.h>
#include "chp.h"
#include "cio.h"
#include "cio_debug.h"
#include "css.h"
#include "device.h"
#include "ioasm.h"
#include "io_sch.h"
#include "blacklist.h"
static struct timer_list recovery_timer;
static DEFINE_SPINLOCK(recovery_lock);
static int recovery_phase;
static const unsigned long recovery_delay[] = { 3, 30, 300 };
/******************* bus type handling ***********************/
/* The Linux driver model distinguishes between a bus type and
* the bus itself. Of course we only have one channel
* subsystem driver and one channel system per machine, but
* we still use the abstraction. T.R. says it's a good idea. */
static int
ccw_bus_match (struct device * dev, struct device_driver * drv)
{
struct ccw_device *cdev = to_ccwdev(dev);
struct ccw_driver *cdrv = to_ccwdrv(drv);
const struct ccw_device_id *ids = cdrv->ids, *found;
if (!ids)
return 0;
found = ccw_device_id_match(ids, &cdev->id);
if (!found)
return 0;
cdev->id.driver_info = found->driver_info;
return 1;
}
/* Store modalias string delimited by prefix/suffix string into buffer with
* specified size. Return length of resulting string (excluding trailing '\0')
* even if string doesn't fit buffer (snprintf semantics). */
static int snprint_alias(char *buf, size_t size,
struct ccw_device_id *id, const char *suffix)
{
int len;
len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
if (len > size)
return len;
buf += len;
size -= len;
if (id->dev_type != 0)
len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
id->dev_model, suffix);
else
len += snprintf(buf, size, "dtdm%s", suffix);
return len;
}
/* Set up environment variables for ccw device uevent. Return 0 on success,
* non-zero otherwise. */
static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct ccw_device *cdev = to_ccwdev(dev);
struct ccw_device_id *id = &(cdev->id);
int ret;
char modalias_buf[30];
/* CU_TYPE= */
ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
if (ret)
return ret;
/* CU_MODEL= */
ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
if (ret)
return ret;
/* The next two can be zero, that's ok for us */
/* DEV_TYPE= */
ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
if (ret)
return ret;
/* DEV_MODEL= */
ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
if (ret)
return ret;
/* MODALIAS= */
snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
return ret;
}
struct bus_type ccw_bus_type;
static void io_subchannel_irq(struct subchannel *);
static int io_subchannel_probe(struct subchannel *);
static int io_subchannel_remove(struct subchannel *);
static void io_subchannel_shutdown(struct subchannel *);
static int io_subchannel_sch_event(struct subchannel *, int);
static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
int);
static struct css_device_id io_subchannel_ids[] = {
{ .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
{ /* end of list */ },
};
MODULE_DEVICE_TABLE(css, io_subchannel_ids);
static int io_subchannel_prepare(struct subchannel *sch)
{
struct ccw_device *cdev;
/*
* Don't allow suspend while a ccw device registration
* is still outstanding.
*/
cdev = sch_get_cdev(sch);
if (cdev && !device_is_registered(&cdev->dev))
return -EAGAIN;
return 0;
}
static struct css_driver io_subchannel_driver = {
.owner = THIS_MODULE,
.subchannel_type = io_subchannel_ids,
.name = "io_subchannel",
.irq = io_subchannel_irq,
.sch_event = io_subchannel_sch_event,
.chp_event = io_subchannel_chp_event,
.probe = io_subchannel_probe,
.remove = io_subchannel_remove,
.shutdown = io_subchannel_shutdown,
.prepare = io_subchannel_prepare,
};
struct workqueue_struct *ccw_device_work;
wait_queue_head_t ccw_device_init_wq;
atomic_t ccw_device_init_count;
static void recovery_func(unsigned long data);
static int __init
init_ccw_bus_type (void)
{
int ret;
init_waitqueue_head(&ccw_device_init_wq);
atomic_set(&ccw_device_init_count, 0);
setup_timer(&recovery_timer, recovery_func, 0);
ccw_device_work = create_singlethread_workqueue("cio");
if (!ccw_device_work)
return -ENOMEM; /* FIXME: better errno ? */
slow_path_wq = create_singlethread_workqueue("kslowcrw");
if (!slow_path_wq) {
ret = -ENOMEM; /* FIXME: better errno ? */
goto out_err;
}
if ((ret = bus_register (&ccw_bus_type)))
goto out_err;
ret = css_driver_register(&io_subchannel_driver);
if (ret)
goto out_err;
wait_event(ccw_device_init_wq,
atomic_read(&ccw_device_init_count) == 0);
flush_workqueue(ccw_device_work);
return 0;
out_err:
if (ccw_device_work)
destroy_workqueue(ccw_device_work);
if (slow_path_wq)
destroy_workqueue(slow_path_wq);
return ret;
}
static void __exit
cleanup_ccw_bus_type (void)
{
css_driver_unregister(&io_subchannel_driver);
bus_unregister(&ccw_bus_type);
destroy_workqueue(ccw_device_work);
}
subsys_initcall(init_ccw_bus_type);
module_exit(cleanup_ccw_bus_type);
/************************ device handling **************************/
/*
* A ccw_device has some interfaces in sysfs in addition to the
* standard ones.
* The following entries are designed to export the information which
* resided in 2.4 in /proc/subchannels. Subchannel and device number
* are obvious, so they don't have an entry :)
* TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
*/
static ssize_t
chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
{
struct subchannel *sch = to_subchannel(dev);
struct chsc_ssd_info *ssd = &sch->ssd_info;
ssize_t ret = 0;
int chp;
int mask;
for (chp = 0; chp < 8; chp++) {
mask = 0x80 >> chp;
if (ssd->path_mask & mask)
ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
else
ret += sprintf(buf + ret, "00 ");
}
ret += sprintf (buf+ret, "\n");
return min((ssize_t)PAGE_SIZE, ret);
}
static ssize_t
pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
{
struct subchannel *sch = to_subchannel(dev);
struct pmcw *pmcw = &sch->schib.pmcw;
return sprintf (buf, "%02x %02x %02x\n",
pmcw->pim, pmcw->pam, pmcw->pom);
}
static ssize_t
devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
{
struct ccw_device *cdev = to_ccwdev(dev);
struct ccw_device_id *id = &(cdev->id);
if (id->dev_type != 0)
return sprintf(buf, "%04x/%02x\n",
id->dev_type, id->dev_model);
else
return sprintf(buf, "n/a\n");
}
static ssize_t
cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
{
struct ccw_device *cdev = to_ccwdev(dev);
struct ccw_device_id *id = &(cdev->id);
return sprintf(buf, "%04x/%02x\n",
id->cu_type, id->cu_model);
}
static ssize_t
modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
{
struct ccw_device *cdev = to_ccwdev(dev);
struct ccw_device_id *id = &(cdev->id);
int len;
len = snprint_alias(buf, PAGE_SIZE, id, "\n");
return len > PAGE_SIZE ? PAGE_SIZE : len;
}
static ssize_t
online_show (struct device *dev, struct device_attribute *attr, char *buf)
{
struct ccw_device *cdev = to_ccwdev(dev);
return sprintf(buf, cdev->online ? "1\n" : "0\n");
}
int ccw_device_is_orphan(struct ccw_device *cdev)
{
return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
}
static void ccw_device_unregister(struct ccw_device *cdev)
{
if (test_and_clear_bit(1, &cdev->private->registered)) {
device_del(&cdev->dev);
/* Release reference from device_initialize(). */
put_device(&cdev->dev);
}
}
static void ccw_device_remove_orphan_cb(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;
ccw_device_unregister(cdev);
/* Release cdev reference for workqueue processing. */
put_device(&cdev->dev);
}
static void
ccw_device_remove_disconnected(struct ccw_device *cdev)
{
unsigned long flags;
/*
* Forced offline in disconnected state means
* 'throw away device'.
*/
if (ccw_device_is_orphan(cdev)) {
/*
* Deregister ccw device.
* Unfortunately, we cannot do this directly from the
* attribute method.
*/
/* Get cdev reference for workqueue processing. */
if (!get_device(&cdev->dev))
return;
spin_lock_irqsave(cdev->ccwlock, flags);
cdev->private->state = DEV_STATE_NOT_OPER;
spin_unlock_irqrestore(cdev->ccwlock, flags);
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_remove_orphan_cb);
queue_work(slow_path_wq, &cdev->private->kick_work);
} else
/* Deregister subchannel, which will kill the ccw device. */
ccw_device_schedule_sch_unregister(cdev);
}
/**
* ccw_device_set_offline() - disable a ccw device for I/O
* @cdev: target ccw device
*
* This function calls the driver's set_offline() function for @cdev, if
* given, and then disables @cdev.
* Returns:
* %0 on success and a negative error value on failure.
* Context:
* enabled, ccw device lock not held
*/
int ccw_device_set_offline(struct ccw_device *cdev)
{
int ret;
if (!cdev)
return -ENODEV;
if (!cdev->online || !cdev->drv)
return -EINVAL;
if (cdev->drv->set_offline) {
ret = cdev->drv->set_offline(cdev);
if (ret != 0)
return ret;
}
cdev->online = 0;
spin_lock_irq(cdev->ccwlock);
/* Wait until a final state or DISCONNECTED is reached */
while (!dev_fsm_final_state(cdev) &&
cdev->private->state != DEV_STATE_DISCONNECTED) {
spin_unlock_irq(cdev->ccwlock);
wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
cdev->private->state == DEV_STATE_DISCONNECTED));
spin_lock_irq(cdev->ccwlock);
}
ret = ccw_device_offline(cdev);
if (ret)
goto error;
spin_unlock_irq(cdev->ccwlock);
wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
cdev->private->state == DEV_STATE_DISCONNECTED));
/* Give up reference from ccw_device_set_online(). */
put_device(&cdev->dev);
return 0;
error:
CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device 0.%x.%04x\n",
ret, cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
cdev->private->state = DEV_STATE_OFFLINE;
dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
spin_unlock_irq(cdev->ccwlock);
/* Give up reference from ccw_device_set_online(). */
put_device(&cdev->dev);
return -ENODEV;
}
/**
* ccw_device_set_online() - enable a ccw device for I/O
* @cdev: target ccw device
*
* This function first enables @cdev and then calls the driver's set_online()
* function for @cdev, if given. If set_online() returns an error, @cdev is
* disabled again.
* Returns:
* %0 on success and a negative error value on failure.
* Context:
* enabled, ccw device lock not held
*/
int ccw_device_set_online(struct ccw_device *cdev)
{
int ret;
int ret2;
if (!cdev)
return -ENODEV;
if (cdev->online || !cdev->drv)
return -EINVAL;
/* Hold on to an extra reference while device is online. */
if (!get_device(&cdev->dev))
return -ENODEV;
spin_lock_irq(cdev->ccwlock);
ret = ccw_device_online(cdev);
spin_unlock_irq(cdev->ccwlock);
if (ret == 0)
wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
else {
CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
"device 0.%x.%04x\n",
ret, cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
/* Give up online reference since onlining failed. */
put_device(&cdev->dev);
return ret;
}
spin_lock_irq(cdev->ccwlock);
/* Check if online processing was successful */
if ((cdev->private->state != DEV_STATE_ONLINE) &&
(cdev->private->state != DEV_STATE_W4SENSE)) {
spin_unlock_irq(cdev->ccwlock);
/* Give up online reference since onlining failed. */
put_device(&cdev->dev);
return -ENODEV;
}
spin_unlock_irq(cdev->ccwlock);
if (cdev->drv->set_online)
ret = cdev->drv->set_online(cdev);
if (ret)
goto rollback;
cdev->online = 1;
return 0;
rollback:
spin_lock_irq(cdev->ccwlock);
/* Wait until a final state or DISCONNECTED is reached */
while (!dev_fsm_final_state(cdev) &&
cdev->private->state != DEV_STATE_DISCONNECTED) {
spin_unlock_irq(cdev->ccwlock);
wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
cdev->private->state == DEV_STATE_DISCONNECTED));
spin_lock_irq(cdev->ccwlock);
}
ret2 = ccw_device_offline(cdev);
if (ret2)
goto error;
spin_unlock_irq(cdev->ccwlock);
wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
cdev->private->state == DEV_STATE_DISCONNECTED));
/* Give up online reference since onlining failed. */
put_device(&cdev->dev);
return ret;
error:
CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, "
"device 0.%x.%04x\n",
ret2, cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
cdev->private->state = DEV_STATE_OFFLINE;
spin_unlock_irq(cdev->ccwlock);
/* Give up online reference since onlining failed. */
put_device(&cdev->dev);
return ret;
}
static int online_store_handle_offline(struct ccw_device *cdev)
{
if (cdev->private->state == DEV_STATE_DISCONNECTED)
ccw_device_remove_disconnected(cdev);
else if (cdev->online && cdev->drv && cdev->drv->set_offline)
return ccw_device_set_offline(cdev);
return 0;
}
static int online_store_recog_and_online(struct ccw_device *cdev)
{
int ret;
/* Do device recognition, if needed. */
if (cdev->private->state == DEV_STATE_BOXED) {
ret = ccw_device_recognition(cdev);
if (ret) {
CIO_MSG_EVENT(0, "Couldn't start recognition "
"for device 0.%x.%04x (ret=%d)\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno, ret);
return ret;
}
wait_event(cdev->private->wait_q,
cdev->private->flags.recog_done);
if (cdev->private->state != DEV_STATE_OFFLINE)
/* recognition failed */
return -EAGAIN;
}
if (cdev->drv && cdev->drv->set_online)
ccw_device_set_online(cdev);
return 0;
}
static int online_store_handle_online(struct ccw_device *cdev, int force)
{
int ret;
ret = online_store_recog_and_online(cdev);
if (ret && !force)
return ret;
if (force && cdev->private->state == DEV_STATE_BOXED) {
ret = ccw_device_stlck(cdev);
if (ret)
return ret;
if (cdev->id.cu_type == 0)
cdev->private->state = DEV_STATE_NOT_OPER;
ret = online_store_recog_and_online(cdev);
if (ret)
return ret;
}
return 0;
}
static ssize_t online_store (struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct ccw_device *cdev = to_ccwdev(dev);
int force, ret;
unsigned long i;
if ((cdev->private->state != DEV_STATE_OFFLINE &&
cdev->private->state != DEV_STATE_ONLINE &&
cdev->private->state != DEV_STATE_BOXED &&
cdev->private->state != DEV_STATE_DISCONNECTED) ||
atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
return -EAGAIN;
if (cdev->drv && !try_module_get(cdev->drv->owner)) {
atomic_set(&cdev->private->onoff, 0);
return -EINVAL;
}
if (!strncmp(buf, "force\n", count)) {
force = 1;
i = 1;
ret = 0;
} else {
force = 0;
ret = strict_strtoul(buf, 16, &i);
}
if (ret)
goto out;
switch (i) {
case 0:
ret = online_store_handle_offline(cdev);
break;
case 1:
ret = online_store_handle_online(cdev, force);
break;
default:
ret = -EINVAL;
}
out:
if (cdev->drv)
module_put(cdev->drv->owner);
atomic_set(&cdev->private->onoff, 0);
return (ret < 0) ? ret : count;
}
static ssize_t
available_show (struct device *dev, struct device_attribute *attr, char *buf)
{
struct ccw_device *cdev = to_ccwdev(dev);
struct subchannel *sch;
if (ccw_device_is_orphan(cdev))
return sprintf(buf, "no device\n");
switch (cdev->private->state) {
case DEV_STATE_BOXED:
return sprintf(buf, "boxed\n");
case DEV_STATE_DISCONNECTED:
case DEV_STATE_DISCONNECTED_SENSE_ID:
case DEV_STATE_NOT_OPER:
sch = to_subchannel(dev->parent);
if (!sch->lpm)
return sprintf(buf, "no path\n");
else
return sprintf(buf, "no device\n");
default:
/* All other states considered fine. */
return sprintf(buf, "good\n");
}
}
static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
static DEVICE_ATTR(online, 0644, online_show, online_store);
static DEVICE_ATTR(availability, 0444, available_show, NULL);
static struct attribute *io_subchannel_attrs[] = {
&dev_attr_chpids.attr,
&dev_attr_pimpampom.attr,
NULL,
};
static struct attribute_group io_subchannel_attr_group = {
.attrs = io_subchannel_attrs,
};
static struct attribute * ccwdev_attrs[] = {
&dev_attr_devtype.attr,
&dev_attr_cutype.attr,
&dev_attr_modalias.attr,
&dev_attr_online.attr,
&dev_attr_cmb_enable.attr,
&dev_attr_availability.attr,
NULL,
};
static struct attribute_group ccwdev_attr_group = {
.attrs = ccwdev_attrs,
};
static struct attribute_group *ccwdev_attr_groups[] = {
&ccwdev_attr_group,
NULL,
};
/* this is a simple abstraction for device_register that sets the
* correct bus type and adds the bus specific files */
static int ccw_device_register(struct ccw_device *cdev)
{
struct device *dev = &cdev->dev;
int ret;
dev->bus = &ccw_bus_type;
ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
if (ret)
return ret;
ret = device_add(dev);
if (ret)
return ret;
set_bit(1, &cdev->private->registered);
return ret;
}
struct match_data {
struct ccw_dev_id dev_id;
struct ccw_device * sibling;
};
static int
match_devno(struct device * dev, void * data)
{
struct match_data * d = data;
struct ccw_device * cdev;
cdev = to_ccwdev(dev);
if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
!ccw_device_is_orphan(cdev) &&
ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
(cdev != d->sibling))
return 1;
return 0;
}
static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
struct ccw_device *sibling)
{
struct device *dev;
struct match_data data;
data.dev_id = *dev_id;
data.sibling = sibling;
dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
return dev ? to_ccwdev(dev) : NULL;
}
static int match_orphan(struct device *dev, void *data)
{
struct ccw_dev_id *dev_id;
struct ccw_device *cdev;
dev_id = data;
cdev = to_ccwdev(dev);
return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
}
static struct ccw_device *
get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
struct ccw_dev_id *dev_id)
{
struct device *dev;
dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
match_orphan);
return dev ? to_ccwdev(dev) : NULL;
}
void ccw_device_do_unbind_bind(struct work_struct *work)
{
struct ccw_device_private *priv;
struct ccw_device *cdev;
struct subchannel *sch;
int ret;
priv = container_of(work, struct ccw_device_private, kick_work);
cdev = priv->cdev;
sch = to_subchannel(cdev->dev.parent);
if (test_bit(1, &cdev->private->registered)) {
device_release_driver(&cdev->dev);
ret = device_attach(&cdev->dev);
WARN_ON(ret == -ENODEV);
}
}
static void
ccw_device_release(struct device *dev)
{
struct ccw_device *cdev;
cdev = to_ccwdev(dev);
/* Release reference of parent subchannel. */
put_device(cdev->dev.parent);
kfree(cdev->private);
kfree(cdev);
}
static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
{
struct ccw_device *cdev;
cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
if (cdev) {
cdev->private = kzalloc(sizeof(struct ccw_device_private),
GFP_KERNEL | GFP_DMA);
if (cdev->private)
return cdev;
}
kfree(cdev);
return ERR_PTR(-ENOMEM);
}
static int io_subchannel_initialize_dev(struct subchannel *sch,
struct ccw_device *cdev)
{
cdev->private->cdev = cdev;
atomic_set(&cdev->private->onoff, 0);
cdev->dev.parent = &sch->dev;
cdev->dev.release = ccw_device_release;
INIT_WORK(&cdev->private->kick_work, NULL);
cdev->dev.groups = ccwdev_attr_groups;
/* Do first half of device_register. */
device_initialize(&cdev->dev);
if (!get_device(&sch->dev)) {
/* Release reference from device_initialize(). */
put_device(&cdev->dev);
return -ENODEV;
}
return 0;
}
static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
{
struct ccw_device *cdev;
int ret;
cdev = io_subchannel_allocate_dev(sch);
if (!IS_ERR(cdev)) {
ret = io_subchannel_initialize_dev(sch, cdev);
if (ret)
cdev = ERR_PTR(ret);
}
return cdev;
}
static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
static void sch_attach_device(struct subchannel *sch,
struct ccw_device *cdev)
{
css_update_ssd_info(sch);
spin_lock_irq(sch->lock);
sch_set_cdev(sch, cdev);
cdev->private->schid = sch->schid;
cdev->ccwlock = sch->lock;
ccw_device_trigger_reprobe(cdev);
spin_unlock_irq(sch->lock);
}
static void sch_attach_disconnected_device(struct subchannel *sch,
struct ccw_device *cdev)
{
struct subchannel *other_sch;
int ret;
/* Get reference for new parent. */
if (!get_device(&sch->dev))
return;
other_sch = to_subchannel(cdev->dev.parent);
/* Note: device_move() changes cdev->dev.parent */
ret = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
if (ret) {
CIO_MSG_EVENT(0, "Moving disconnected device 0.%x.%04x failed "
"(ret=%d)!\n", cdev->private->dev_id.ssid,
cdev->private->dev_id.devno, ret);
/* Put reference for new parent. */
put_device(&sch->dev);
return;
}
sch_set_cdev(other_sch, NULL);
/* No need to keep a subchannel without ccw device around. */
css_sch_device_unregister(other_sch);
sch_attach_device(sch, cdev);
/* Put reference for old parent. */
put_device(&other_sch->dev);
}
static void sch_attach_orphaned_device(struct subchannel *sch,
struct ccw_device *cdev)
{
int ret;
struct subchannel *pseudo_sch;
/* Get reference for new parent. */
if (!get_device(&sch->dev))
return;
pseudo_sch = to_subchannel(cdev->dev.parent);
/*
* Try to move the ccw device to its new subchannel.
* Note: device_move() changes cdev->dev.parent
*/
ret = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
if (ret) {
CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
"failed (ret=%d)!\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno, ret);
/* Put reference for new parent. */
put_device(&sch->dev);
return;
}
sch_attach_device(sch, cdev);
/* Put reference on pseudo subchannel. */
put_device(&pseudo_sch->dev);
}
static void sch_create_and_recog_new_device(struct subchannel *sch)
{
struct ccw_device *cdev;
/* Need to allocate a new ccw device. */
cdev = io_subchannel_create_ccwdev(sch);
if (IS_ERR(cdev)) {
/* OK, we did everything we could... */
css_sch_device_unregister(sch);
return;
}
spin_lock_irq(sch->lock);
sch_set_cdev(sch, cdev);
spin_unlock_irq(sch->lock);
/* Start recognition for the new ccw device. */
if (io_subchannel_recog(cdev, sch)) {
spin_lock_irq(sch->lock);
sch_set_cdev(sch, NULL);
spin_unlock_irq(sch->lock);
css_sch_device_unregister(sch);
/* Put reference from io_subchannel_create_ccwdev(). */
put_device(&sch->dev);
/* Give up initial reference. */
put_device(&cdev->dev);
}
}
void ccw_device_move_to_orphanage(struct work_struct *work)
{
struct ccw_device_private *priv;
struct ccw_device *cdev;
struct ccw_device *replacing_cdev;
struct subchannel *sch;
int ret;
struct channel_subsystem *css;
struct ccw_dev_id dev_id;
priv = container_of(work, struct ccw_device_private, kick_work);
cdev = priv->cdev;
sch = to_subchannel(cdev->dev.parent);
css = to_css(sch->dev.parent);
dev_id.devno = sch->schib.pmcw.dev;
dev_id.ssid = sch->schid.ssid;
/* Increase refcount for pseudo subchannel. */
get_device(&css->pseudo_subchannel->dev);
/*
* Move the orphaned ccw device to the orphanage so the replacing
* ccw device can take its place on the subchannel.
* Note: device_move() changes cdev->dev.parent
*/
ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev,
DPM_ORDER_NONE);
if (ret) {
CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
"(ret=%d)!\n", cdev->private->dev_id.ssid,
cdev->private->dev_id.devno, ret);
/* Decrease refcount for pseudo subchannel again. */
put_device(&css->pseudo_subchannel->dev);
return;
}
cdev->ccwlock = css->pseudo_subchannel->lock;
/*
* Search for the replacing ccw device
* - among the disconnected devices
* - in the orphanage
*/
replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
if (replacing_cdev) {
sch_attach_disconnected_device(sch, replacing_cdev);
/* Release reference from get_disc_ccwdev_by_dev_id() */
put_device(&replacing_cdev->dev);
/* Release reference of subchannel from old cdev. */
put_device(&sch->dev);
return;
}
replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
if (replacing_cdev) {
sch_attach_orphaned_device(sch, replacing_cdev);
/* Release reference from get_orphaned_ccwdev_by_dev_id() */
put_device(&replacing_cdev->dev);
/* Release reference of subchannel from old cdev. */
put_device(&sch->dev);
return;
}
sch_create_and_recog_new_device(sch);
/* Release reference of subchannel from old cdev. */
put_device(&sch->dev);
}
/*
* Register recognized device.
*/
static void
io_subchannel_register(struct work_struct *work)
{
struct ccw_device_private *priv;
struct ccw_device *cdev;
struct subchannel *sch;
int ret;
unsigned long flags;
priv = container_of(work, struct ccw_device_private, kick_work);
cdev = priv->cdev;
sch = to_subchannel(cdev->dev.parent);
/*
* Check if subchannel is still registered. It may have become
* unregistered if a machine check hit us after finishing
* device recognition but before the register work could be
* queued.
*/
if (!device_is_registered(&sch->dev))
goto out_err;
css_update_ssd_info(sch);
/*
* io_subchannel_register() will also be called after device
* recognition has been done for a boxed device (which will already
* be registered). We need to reprobe since we may now have sense id
* information.
*/
if (device_is_registered(&cdev->dev)) {
if (!cdev->drv) {
ret = device_reprobe(&cdev->dev);
if (ret)
/* We can't do much here. */
CIO_MSG_EVENT(0, "device_reprobe() returned"
" %d for 0.%x.%04x\n", ret,
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
}
goto out;
}
/*
* Now we know this subchannel will stay, we can throw
* our delayed uevent.
*/
dev_set_uevent_suppress(&sch->dev, 0);
kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
/* make it known to the system */
ret = ccw_device_register(cdev);
if (ret) {
CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno, ret);
spin_lock_irqsave(sch->lock, flags);
sch_set_cdev(sch, NULL);
spin_unlock_irqrestore(sch->lock, flags);
/* Release initial device reference. */
put_device(&cdev->dev);
goto out_err;
}
out:
cdev->private->flags.recog_done = 1;
wake_up(&cdev->private->wait_q);
out_err:
/* Release reference for workqueue processing. */
put_device(&cdev->dev);
if (atomic_dec_and_test(&ccw_device_init_count))
wake_up(&ccw_device_init_wq);
}
static void ccw_device_call_sch_unregister(struct work_struct *work)
{
struct ccw_device_private *priv;
struct ccw_device *cdev;
struct subchannel *sch;
priv = container_of(work, struct ccw_device_private, kick_work);
cdev = priv->cdev;
/* Get subchannel reference for local processing. */
if (!get_device(cdev->dev.parent))
return;
sch = to_subchannel(cdev->dev.parent);
css_sch_device_unregister(sch);
/* Release cdev reference for workqueue processing.*/
put_device(&cdev->dev);
/* Release subchannel reference for local processing. */
put_device(&sch->dev);
}
void ccw_device_schedule_sch_unregister(struct ccw_device *cdev)
{
/* Get cdev reference for workqueue processing. */
if (!get_device(&cdev->dev))
return;
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_call_sch_unregister);
queue_work(slow_path_wq, &cdev->private->kick_work);
}
/*
* subchannel recognition done. Called from the state machine.
*/
void
io_subchannel_recog_done(struct ccw_device *cdev)
{
if (css_init_done == 0) {
cdev->private->flags.recog_done = 1;
return;
}
switch (cdev->private->state) {
case DEV_STATE_BOXED:
/* Device did not respond in time. */
case DEV_STATE_NOT_OPER:
cdev->private->flags.recog_done = 1;
ccw_device_schedule_sch_unregister(cdev);
if (atomic_dec_and_test(&ccw_device_init_count))
wake_up(&ccw_device_init_wq);
break;
case DEV_STATE_OFFLINE:
/*
* We can't register the device in interrupt context so
* we schedule a work item.
*/
if (!get_device(&cdev->dev))
break;
PREPARE_WORK(&cdev->private->kick_work,
io_subchannel_register);
queue_work(slow_path_wq, &cdev->private->kick_work);
break;
}
}
static int
io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
{
int rc;
struct ccw_device_private *priv;
sch_set_cdev(sch, cdev);
cdev->ccwlock = sch->lock;
/* Init private data. */
priv = cdev->private;
priv->dev_id.devno = sch->schib.pmcw.dev;
priv->dev_id.ssid = sch->schid.ssid;
priv->schid = sch->schid;
priv->state = DEV_STATE_NOT_OPER;
INIT_LIST_HEAD(&priv->cmb_list);
init_waitqueue_head(&priv->wait_q);
init_timer(&priv->timer);
/* Increase counter of devices currently in recognition. */
atomic_inc(&ccw_device_init_count);
/* Start async. device sensing. */
spin_lock_irq(sch->lock);
rc = ccw_device_recognition(cdev);
spin_unlock_irq(sch->lock);
if (rc) {
if (atomic_dec_and_test(&ccw_device_init_count))
wake_up(&ccw_device_init_wq);
}
return rc;
}
static void ccw_device_move_to_sch(struct work_struct *work)
{
struct ccw_device_private *priv;
int rc;
struct subchannel *sch;
struct ccw_device *cdev;
struct subchannel *former_parent;
priv = container_of(work, struct ccw_device_private, kick_work);
sch = priv->sch;
cdev = priv->cdev;
former_parent = to_subchannel(cdev->dev.parent);
/* Get reference for new parent. */
if (!get_device(&sch->dev))
return;
mutex_lock(&sch->reg_mutex);
/*
* Try to move the ccw device to its new subchannel.
* Note: device_move() changes cdev->dev.parent
*/
rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
mutex_unlock(&sch->reg_mutex);
if (rc) {
CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to subchannel "
"0.%x.%04x failed (ret=%d)!\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno, sch->schid.ssid,
sch->schid.sch_no, rc);
css_sch_device_unregister(sch);
/* Put reference for new parent again. */
put_device(&sch->dev);
goto out;
}
if (!sch_is_pseudo_sch(former_parent)) {
spin_lock_irq(former_parent->lock);
sch_set_cdev(former_parent, NULL);
spin_unlock_irq(former_parent->lock);
css_sch_device_unregister(former_parent);
/* Reset intparm to zeroes. */
former_parent->config.intparm = 0;
cio_commit_config(former_parent);
}
sch_attach_device(sch, cdev);
out:
/* Put reference for old parent. */
put_device(&former_parent->dev);
put_device(&cdev->dev);
}
static void io_subchannel_irq(struct subchannel *sch)
{
struct ccw_device *cdev;
cdev = sch_get_cdev(sch);
CIO_TRACE_EVENT(6, "IRQ");
CIO_TRACE_EVENT(6, dev_name(&sch->dev));
if (cdev)
dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
}
void io_subchannel_init_config(struct subchannel *sch)
{
memset(&sch->config, 0, sizeof(sch->config));
sch->config.csense = 1;
/* Use subchannel mp mode when there is more than 1 installed CHPID. */
if ((sch->schib.pmcw.pim & (sch->schib.pmcw.pim - 1)) != 0)
sch->config.mp = 1;
}
static void io_subchannel_init_fields(struct subchannel *sch)
{
if (cio_is_console(sch->schid))
sch->opm = 0xff;
else
sch->opm = chp_get_sch_opm(sch);
sch->lpm = sch->schib.pmcw.pam & sch->opm;
sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
" - PIM = %02X, PAM = %02X, POM = %02X\n",
sch->schib.pmcw.dev, sch->schid.ssid,
sch->schid.sch_no, sch->schib.pmcw.pim,
sch->schib.pmcw.pam, sch->schib.pmcw.pom);
io_subchannel_init_config(sch);
}
static void io_subchannel_do_unreg(struct work_struct *work)
{
struct subchannel *sch;
sch = container_of(work, struct subchannel, work);
css_sch_device_unregister(sch);
put_device(&sch->dev);
}
/* Schedule unregister if we have no cdev. */
static void io_subchannel_schedule_removal(struct subchannel *sch)
{
get_device(&sch->dev);
INIT_WORK(&sch->work, io_subchannel_do_unreg);
queue_work(slow_path_wq, &sch->work);
}
/*
* Note: We always return 0 so that we bind to the device even on error.
* This is needed so that our remove function is called on unregister.
*/
static int io_subchannel_probe(struct subchannel *sch)
{
struct ccw_device *cdev;
int rc;
unsigned long flags;
struct ccw_dev_id dev_id;
cdev = sch_get_cdev(sch);
if (cdev) {
rc = sysfs_create_group(&sch->dev.kobj,
&io_subchannel_attr_group);
if (rc)
CIO_MSG_EVENT(0, "Failed to create io subchannel "
"attributes for subchannel "
"0.%x.%04x (rc=%d)\n",
sch->schid.ssid, sch->schid.sch_no, rc);
/*
* This subchannel already has an associated ccw_device.
* Throw the delayed uevent for the subchannel, register
* the ccw_device and exit. This happens for all early
* devices, e.g. the console.
*/
dev_set_uevent_suppress(&sch->dev, 0);
kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
cdev->dev.groups = ccwdev_attr_groups;
device_initialize(&cdev->dev);
ccw_device_register(cdev);
/*
* Check if the device is already online. If it is
* the reference count needs to be corrected since we
* didn't obtain a reference in ccw_device_set_online.
*/
if (cdev->private->state != DEV_STATE_NOT_OPER &&
cdev->private->state != DEV_STATE_OFFLINE &&
cdev->private->state != DEV_STATE_BOXED)
get_device(&cdev->dev);
return 0;
}
io_subchannel_init_fields(sch);
rc = cio_commit_config(sch);
if (rc)
goto out_schedule;
rc = sysfs_create_group(&sch->dev.kobj,
&io_subchannel_attr_group);
if (rc)
goto out_schedule;
/* Allocate I/O subchannel private data. */
sch->private = kzalloc(sizeof(struct io_subchannel_private),
GFP_KERNEL | GFP_DMA);
if (!sch->private)
goto out_err;
/*
* First check if a fitting device may be found amongst the
* disconnected devices or in the orphanage.
*/
dev_id.devno = sch->schib.pmcw.dev;
dev_id.ssid = sch->schid.ssid;
cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
if (!cdev)
cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
&dev_id);
if (cdev) {
/*
* Schedule moving the device until when we have a registered
* subchannel to move to and succeed the probe. We can
* unregister later again, when the probe is through.
*/
cdev->private->sch = sch;
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_move_to_sch);
queue_work(slow_path_wq, &cdev->private->kick_work);
return 0;
}
cdev = io_subchannel_create_ccwdev(sch);
if (IS_ERR(cdev))
goto out_err;
rc = io_subchannel_recog(cdev, sch);
if (rc) {
spin_lock_irqsave(sch->lock, flags);
io_subchannel_recog_done(cdev);
spin_unlock_irqrestore(sch->lock, flags);
}
return 0;
out_err:
kfree(sch->private);
sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
out_schedule:
io_subchannel_schedule_removal(sch);
return 0;
}
static int
io_subchannel_remove (struct subchannel *sch)
{
struct ccw_device *cdev;
unsigned long flags;
cdev = sch_get_cdev(sch);
if (!cdev)
return 0;
/* Set ccw device to not operational and drop reference. */
spin_lock_irqsave(cdev->ccwlock, flags);
sch_set_cdev(sch, NULL);
cdev->private->state = DEV_STATE_NOT_OPER;
spin_unlock_irqrestore(cdev->ccwlock, flags);
ccw_device_unregister(cdev);
kfree(sch->private);
sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
return 0;
}
static int io_subchannel_notify(struct subchannel *sch, int event)
{
struct ccw_device *cdev;
cdev = sch_get_cdev(sch);
if (!cdev)
return 0;
return ccw_device_notify(cdev, event);
}
static void io_subchannel_verify(struct subchannel *sch)
{
struct ccw_device *cdev;
cdev = sch_get_cdev(sch);
if (cdev)
dev_fsm_event(cdev, DEV_EVENT_VERIFY);
}
static int check_for_io_on_path(struct subchannel *sch, int mask)
{
if (cio_update_schib(sch))
return 0;
if (scsw_actl(&sch->schib.scsw) && sch->schib.pmcw.lpum == mask)
return 1;
return 0;
}
static void terminate_internal_io(struct subchannel *sch,
struct ccw_device *cdev)
{
if (cio_clear(sch)) {
/* Recheck device in case clear failed. */
sch->lpm = 0;
if (cdev->online)
dev_fsm_event(cdev, DEV_EVENT_VERIFY);
else
css_schedule_eval(sch->schid);
return;
}
cdev->private->state = DEV_STATE_CLEAR_VERIFY;
/* Request retry of internal operation. */
cdev->private->flags.intretry = 1;
/* Call handler. */
if (cdev->handler)
cdev->handler(cdev, cdev->private->intparm,
ERR_PTR(-EIO));
}
static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
{
struct ccw_device *cdev;
cdev = sch_get_cdev(sch);
if (!cdev)
return;
if (check_for_io_on_path(sch, mask)) {
if (cdev->private->state == DEV_STATE_ONLINE)
ccw_device_kill_io(cdev);
else {
terminate_internal_io(sch, cdev);
/* Re-start path verification. */
dev_fsm_event(cdev, DEV_EVENT_VERIFY);
}
} else
/* trigger path verification. */
dev_fsm_event(cdev, DEV_EVENT_VERIFY);
}
static int io_subchannel_chp_event(struct subchannel *sch,
struct chp_link *link, int event)
{
int mask;
mask = chp_ssd_get_mask(&sch->ssd_info, link);
if (!mask)
return 0;
switch (event) {
case CHP_VARY_OFF:
sch->opm &= ~mask;
sch->lpm &= ~mask;
io_subchannel_terminate_path(sch, mask);
break;
case CHP_VARY_ON:
sch->opm |= mask;
sch->lpm |= mask;
io_subchannel_verify(sch);
break;
case CHP_OFFLINE:
if (cio_update_schib(sch))
return -ENODEV;
io_subchannel_terminate_path(sch, mask);
break;
case CHP_ONLINE:
if (cio_update_schib(sch))
return -ENODEV;
sch->lpm |= mask & sch->opm;
io_subchannel_verify(sch);
break;
}
return 0;
}
static void
io_subchannel_shutdown(struct subchannel *sch)
{
struct ccw_device *cdev;
int ret;
cdev = sch_get_cdev(sch);
if (cio_is_console(sch->schid))
return;
if (!sch->schib.pmcw.ena)
/* Nothing to do. */
return;
ret = cio_disable_subchannel(sch);
if (ret != -EBUSY)
/* Subchannel is disabled, we're done. */
return;
cdev->private->state = DEV_STATE_QUIESCE;
if (cdev->handler)
cdev->handler(cdev, cdev->private->intparm,
ERR_PTR(-EIO));
ret = ccw_device_cancel_halt_clear(cdev);
if (ret == -EBUSY) {
ccw_device_set_timeout(cdev, HZ/10);
wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
}
cio_disable_subchannel(sch);
}
static int io_subchannel_get_status(struct subchannel *sch)
{
struct schib schib;
if (stsch(sch->schid, &schib) || !schib.pmcw.dnv)
return CIO_GONE;
if (sch->schib.pmcw.dnv && (schib.pmcw.dev != sch->schib.pmcw.dev))
return CIO_REVALIDATE;
if (!sch->lpm)
return CIO_NO_PATH;
return CIO_OPER;
}
static int device_is_disconnected(struct ccw_device *cdev)
{
if (!cdev)
return 0;
return (cdev->private->state == DEV_STATE_DISCONNECTED ||
cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
}
static int recovery_check(struct device *dev, void *data)
{
struct ccw_device *cdev = to_ccwdev(dev);
int *redo = data;
spin_lock_irq(cdev->ccwlock);
switch (cdev->private->state) {
case DEV_STATE_DISCONNECTED:
CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
dev_fsm_event(cdev, DEV_EVENT_VERIFY);
*redo = 1;
break;
case DEV_STATE_DISCONNECTED_SENSE_ID:
*redo = 1;
break;
}
spin_unlock_irq(cdev->ccwlock);
return 0;
}
static void recovery_work_func(struct work_struct *unused)
{
int redo = 0;
bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
if (redo) {
spin_lock_irq(&recovery_lock);
if (!timer_pending(&recovery_timer)) {
if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
recovery_phase++;
mod_timer(&recovery_timer, jiffies +
recovery_delay[recovery_phase] * HZ);
}
spin_unlock_irq(&recovery_lock);
} else
CIO_MSG_EVENT(4, "recovery: end\n");
}
static DECLARE_WORK(recovery_work, recovery_work_func);
static void recovery_func(unsigned long data)
{
/*
* We can't do our recovery in softirq context and it's not
* performance critical, so we schedule it.
*/
schedule_work(&recovery_work);
}
static void ccw_device_schedule_recovery(void)
{
unsigned long flags;
CIO_MSG_EVENT(4, "recovery: schedule\n");
spin_lock_irqsave(&recovery_lock, flags);
if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
recovery_phase = 0;
mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
}
spin_unlock_irqrestore(&recovery_lock, flags);
}
static int purge_fn(struct device *dev, void *data)
{
struct ccw_device *cdev = to_ccwdev(dev);
struct ccw_device_private *priv = cdev->private;
int unreg;
spin_lock_irq(cdev->ccwlock);
unreg = is_blacklisted(priv->dev_id.ssid, priv->dev_id.devno) &&
(priv->state == DEV_STATE_OFFLINE);
spin_unlock_irq(cdev->ccwlock);
if (!unreg)
goto out;
CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", priv->dev_id.ssid,
priv->dev_id.devno);
ccw_device_schedule_sch_unregister(cdev);
out:
/* Abort loop in case of pending signal. */
if (signal_pending(current))
return -EINTR;
return 0;
}
/**
* ccw_purge_blacklisted - purge unused, blacklisted devices
*
* Unregister all ccw devices that are offline and on the blacklist.
*/
int ccw_purge_blacklisted(void)
{
CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
return 0;
}
static void device_set_disconnected(struct ccw_device *cdev)
{
if (!cdev)
return;
ccw_device_set_timeout(cdev, 0);
cdev->private->flags.fake_irb = 0;
cdev->private->state = DEV_STATE_DISCONNECTED;
if (cdev->online)
ccw_device_schedule_recovery();
}
void ccw_device_set_notoper(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
CIO_TRACE_EVENT(2, "notoper");
CIO_TRACE_EVENT(2, dev_name(&sch->dev));
ccw_device_set_timeout(cdev, 0);
cio_disable_subchannel(sch);
cdev->private->state = DEV_STATE_NOT_OPER;
}
static int io_subchannel_sch_event(struct subchannel *sch, int slow)
{
int event, ret, disc;
unsigned long flags;
enum { NONE, UNREGISTER, UNREGISTER_PROBE, REPROBE, DISC } action;
struct ccw_device *cdev;
spin_lock_irqsave(sch->lock, flags);
cdev = sch_get_cdev(sch);
disc = device_is_disconnected(cdev);
if (disc && slow) {
/* Disconnected devices are evaluated directly only.*/
spin_unlock_irqrestore(sch->lock, flags);
return 0;
}
/* No interrupt after machine check - kill pending timers. */
if (cdev)
ccw_device_set_timeout(cdev, 0);
if (!disc && !slow) {
/* Non-disconnected devices are evaluated on the slow path. */
spin_unlock_irqrestore(sch->lock, flags);
return -EAGAIN;
}
event = io_subchannel_get_status(sch);
CIO_MSG_EVENT(4, "Evaluating schid 0.%x.%04x, event %d, %s, %s path.\n",
sch->schid.ssid, sch->schid.sch_no, event,
disc ? "disconnected" : "normal",
slow ? "slow" : "fast");
/* Analyze subchannel status. */
action = NONE;
switch (event) {
case CIO_NO_PATH:
if (disc) {
/* Check if paths have become available. */
action = REPROBE;
break;
}
/* fall through */
case CIO_GONE:
/* Ask driver what to do with device. */
if (io_subchannel_notify(sch, event))
action = DISC;
else
action = UNREGISTER;
break;
case CIO_REVALIDATE:
/* Device will be removed, so no notify necessary. */
if (disc)
/* Reprobe because immediate unregister might block. */
action = REPROBE;
else
action = UNREGISTER_PROBE;
break;
case CIO_OPER:
if (disc)
/* Get device operational again. */
action = REPROBE;
break;
}
/* Perform action. */
ret = 0;
switch (action) {
case UNREGISTER:
case UNREGISTER_PROBE:
ccw_device_set_notoper(cdev);
/* Unregister device (will use subchannel lock). */
spin_unlock_irqrestore(sch->lock, flags);
css_sch_device_unregister(sch);
spin_lock_irqsave(sch->lock, flags);
break;
case REPROBE:
ccw_device_trigger_reprobe(cdev);
break;
case DISC:
device_set_disconnected(cdev);
break;
default:
break;
}
spin_unlock_irqrestore(sch->lock, flags);
/* Probe if necessary. */
if (action == UNREGISTER_PROBE)
ret = css_probe_device(sch->schid);
return ret;
}
#ifdef CONFIG_CCW_CONSOLE
static struct ccw_device console_cdev;
static struct ccw_device_private console_private;
static int console_cdev_in_use;
static DEFINE_SPINLOCK(ccw_console_lock);
spinlock_t * cio_get_console_lock(void)
{
return &ccw_console_lock;
}
static int ccw_device_console_enable(struct ccw_device *cdev,
struct subchannel *sch)
{
int rc;
/* Attach subchannel private data. */
sch->private = cio_get_console_priv();
memset(sch->private, 0, sizeof(struct io_subchannel_private));
io_subchannel_init_fields(sch);
rc = cio_commit_config(sch);
if (rc)
return rc;
sch->driver = &io_subchannel_driver;
/* Initialize the ccw_device structure. */
cdev->dev.parent= &sch->dev;
rc = io_subchannel_recog(cdev, sch);
if (rc)
return rc;
/* Now wait for the async. recognition to come to an end. */
spin_lock_irq(cdev->ccwlock);
while (!dev_fsm_final_state(cdev))
wait_cons_dev();
rc = -EIO;
if (cdev->private->state != DEV_STATE_OFFLINE)
goto out_unlock;
ccw_device_online(cdev);
while (!dev_fsm_final_state(cdev))
wait_cons_dev();
if (cdev->private->state != DEV_STATE_ONLINE)
goto out_unlock;
rc = 0;
out_unlock:
spin_unlock_irq(cdev->ccwlock);
return 0;
}
struct ccw_device *
ccw_device_probe_console(void)
{
struct subchannel *sch;
int ret;
if (xchg(&console_cdev_in_use, 1) != 0)
return ERR_PTR(-EBUSY);
sch = cio_probe_console();
if (IS_ERR(sch)) {
console_cdev_in_use = 0;
return (void *) sch;
}
memset(&console_cdev, 0, sizeof(struct ccw_device));
memset(&console_private, 0, sizeof(struct ccw_device_private));
console_cdev.private = &console_private;
console_private.cdev = &console_cdev;
ret = ccw_device_console_enable(&console_cdev, sch);
if (ret) {
cio_release_console();
console_cdev_in_use = 0;
return ERR_PTR(ret);
}
console_cdev.online = 1;
return &console_cdev;
}
static int ccw_device_pm_restore(struct device *dev);
int ccw_device_force_console(void)
{
if (!console_cdev_in_use)
return -ENODEV;
return ccw_device_pm_restore(&console_cdev.dev);
}
EXPORT_SYMBOL_GPL(ccw_device_force_console);
#endif
/*
* get ccw_device matching the busid, but only if owned by cdrv
*/
static int
__ccwdev_check_busid(struct device *dev, void *id)
{
char *bus_id;
bus_id = id;
return (strcmp(bus_id, dev_name(dev)) == 0);
}
/**
* get_ccwdev_by_busid() - obtain device from a bus id
* @cdrv: driver the device is owned by
* @bus_id: bus id of the device to be searched
*
* This function searches all devices owned by @cdrv for a device with a bus
* id matching @bus_id.
* Returns:
* If a match is found, its reference count of the found device is increased
* and it is returned; else %NULL is returned.
*/
struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
const char *bus_id)
{
struct device *dev;
struct device_driver *drv;
drv = get_driver(&cdrv->driver);
if (!drv)
return NULL;
dev = driver_find_device(drv, NULL, (void *)bus_id,
__ccwdev_check_busid);
put_driver(drv);
return dev ? to_ccwdev(dev) : NULL;
}
/************************** device driver handling ************************/
/* This is the implementation of the ccw_driver class. The probe, remove
* and release methods are initially very similar to the device_driver
* implementations, with the difference that they have ccw_device
* arguments.
*
* A ccw driver also contains the information that is needed for
* device matching.
*/
static int
ccw_device_probe (struct device *dev)
{
struct ccw_device *cdev = to_ccwdev(dev);
struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
int ret;
cdev->drv = cdrv; /* to let the driver call _set_online */
ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
if (ret) {
cdev->drv = NULL;
return ret;
}
return 0;
}
static int
ccw_device_remove (struct device *dev)
{
struct ccw_device *cdev = to_ccwdev(dev);
struct ccw_driver *cdrv = cdev->drv;
int ret;
if (cdrv->remove)
cdrv->remove(cdev);
if (cdev->online) {
cdev->online = 0;
spin_lock_irq(cdev->ccwlock);
ret = ccw_device_offline(cdev);
spin_unlock_irq(cdev->ccwlock);
if (ret == 0)
wait_event(cdev->private->wait_q,
dev_fsm_final_state(cdev));
else
CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
"device 0.%x.%04x\n",
ret, cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
/* Give up reference obtained in ccw_device_set_online(). */
put_device(&cdev->dev);
}
ccw_device_set_timeout(cdev, 0);
cdev->drv = NULL;
return 0;
}
static void ccw_device_shutdown(struct device *dev)
{
struct ccw_device *cdev;
cdev = to_ccwdev(dev);
if (cdev->drv && cdev->drv->shutdown)
cdev->drv->shutdown(cdev);
disable_cmf(cdev);
}
static int ccw_device_pm_prepare(struct device *dev)
{
struct ccw_device *cdev = to_ccwdev(dev);
if (work_pending(&cdev->private->kick_work))
return -EAGAIN;
/* Fail while device is being set online/offline. */
if (atomic_read(&cdev->private->onoff))
return -EAGAIN;
if (cdev->online && cdev->drv && cdev->drv->prepare)
return cdev->drv->prepare(cdev);
return 0;
}
static void ccw_device_pm_complete(struct device *dev)
{
struct ccw_device *cdev = to_ccwdev(dev);
if (cdev->online && cdev->drv && cdev->drv->complete)
cdev->drv->complete(cdev);
}
static int ccw_device_pm_freeze(struct device *dev)
{
struct ccw_device *cdev = to_ccwdev(dev);
struct subchannel *sch = to_subchannel(cdev->dev.parent);
int ret, cm_enabled;
/* Fail suspend while device is in transistional state. */
if (!dev_fsm_final_state(cdev))
return -EAGAIN;
if (!cdev->online)
return 0;
if (cdev->drv && cdev->drv->freeze) {
ret = cdev->drv->freeze(cdev);
if (ret)
return ret;
}
spin_lock_irq(sch->lock);
cm_enabled = cdev->private->cmb != NULL;
spin_unlock_irq(sch->lock);
if (cm_enabled) {
/* Don't have the css write on memory. */
ret = ccw_set_cmf(cdev, 0);
if (ret)
return ret;
}
/* From here on, disallow device driver I/O. */
spin_lock_irq(sch->lock);
ret = cio_disable_subchannel(sch);
spin_unlock_irq(sch->lock);
return ret;
}
static int ccw_device_pm_thaw(struct device *dev)
{
struct ccw_device *cdev = to_ccwdev(dev);
struct subchannel *sch = to_subchannel(cdev->dev.parent);
int ret, cm_enabled;
if (!cdev->online)
return 0;
spin_lock_irq(sch->lock);
/* Allow device driver I/O again. */
ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
cm_enabled = cdev->private->cmb != NULL;
spin_unlock_irq(sch->lock);
if (ret)
return ret;
if (cm_enabled) {
ret = ccw_set_cmf(cdev, 1);
if (ret)
return ret;
}
if (cdev->drv && cdev->drv->thaw)
ret = cdev->drv->thaw(cdev);
return ret;
}
static void __ccw_device_pm_restore(struct ccw_device *cdev)
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
int ret;
if (cio_is_console(sch->schid))
goto out;
/*
* While we were sleeping, devices may have gone or become
* available again. Kick re-detection.
*/
spin_lock_irq(sch->lock);
cdev->private->flags.resuming = 1;
ret = ccw_device_recognition(cdev);
spin_unlock_irq(sch->lock);
if (ret) {
CIO_MSG_EVENT(0, "Couldn't start recognition for device "
"0.%x.%04x (ret=%d)\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno, ret);
spin_lock_irq(sch->lock);
cdev->private->state = DEV_STATE_DISCONNECTED;
spin_unlock_irq(sch->lock);
/* notify driver after the resume cb */
goto out;
}
wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
cdev->private->state == DEV_STATE_DISCONNECTED);
out:
cdev->private->flags.resuming = 0;
}
static int resume_handle_boxed(struct ccw_device *cdev)
{
cdev->private->state = DEV_STATE_BOXED;
if (ccw_device_notify(cdev, CIO_BOXED))
return 0;
ccw_device_schedule_sch_unregister(cdev);
return -ENODEV;
}
static int resume_handle_disc(struct ccw_device *cdev)
{
cdev->private->state = DEV_STATE_DISCONNECTED;
if (ccw_device_notify(cdev, CIO_GONE))
return 0;
ccw_device_schedule_sch_unregister(cdev);
return -ENODEV;
}
static int ccw_device_pm_restore(struct device *dev)
{
struct ccw_device *cdev = to_ccwdev(dev);
struct subchannel *sch = to_subchannel(cdev->dev.parent);
int ret = 0, cm_enabled;
__ccw_device_pm_restore(cdev);
spin_lock_irq(sch->lock);
if (cio_is_console(sch->schid)) {
cio_enable_subchannel(sch, (u32)(addr_t)sch);
spin_unlock_irq(sch->lock);
goto out_restore;
}
cdev->private->flags.donotify = 0;
/* check recognition results */
switch (cdev->private->state) {
case DEV_STATE_OFFLINE:
break;
case DEV_STATE_BOXED:
ret = resume_handle_boxed(cdev);
spin_unlock_irq(sch->lock);
if (ret)
goto out;
goto out_restore;
case DEV_STATE_DISCONNECTED:
goto out_disc_unlock;
default:
goto out_unreg_unlock;
}
/* check if the device id has changed */
if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
CIO_MSG_EVENT(0, "resume: sch 0.%x.%04x: failed (devno "
"changed from %04x to %04x)\n",
sch->schid.ssid, sch->schid.sch_no,
cdev->private->dev_id.devno,
sch->schib.pmcw.dev);
goto out_unreg_unlock;
}
/* check if the device type has changed */
if (!ccw_device_test_sense_data(cdev)) {
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);
ret = -ENODEV;
goto out_unlock;
}
if (!cdev->online) {
ret = 0;
goto out_unlock;
}
ret = ccw_device_online(cdev);
if (ret)
goto out_disc_unlock;
cm_enabled = cdev->private->cmb != NULL;
spin_unlock_irq(sch->lock);
wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
if (cdev->private->state != DEV_STATE_ONLINE) {
spin_lock_irq(sch->lock);
goto out_disc_unlock;
}
if (cm_enabled) {
ret = ccw_set_cmf(cdev, 1);
if (ret) {
CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
"(rc=%d)\n", cdev->private->dev_id.ssid,
cdev->private->dev_id.devno, ret);
ret = 0;
}
}
out_restore:
if (cdev->online && cdev->drv && cdev->drv->restore)
ret = cdev->drv->restore(cdev);
out:
return ret;
out_disc_unlock:
ret = resume_handle_disc(cdev);
spin_unlock_irq(sch->lock);
if (ret)
return ret;
goto out_restore;
out_unreg_unlock:
ccw_device_schedule_sch_unregister(cdev);
ret = -ENODEV;
out_unlock:
spin_unlock_irq(sch->lock);
return ret;
}
static struct dev_pm_ops ccw_pm_ops = {
.prepare = ccw_device_pm_prepare,
.complete = ccw_device_pm_complete,
.freeze = ccw_device_pm_freeze,
.thaw = ccw_device_pm_thaw,
.restore = ccw_device_pm_restore,
};
struct bus_type ccw_bus_type = {
.name = "ccw",
.match = ccw_bus_match,
.uevent = ccw_uevent,
.probe = ccw_device_probe,
.remove = ccw_device_remove,
.shutdown = ccw_device_shutdown,
.pm = &ccw_pm_ops,
};
/**
* ccw_driver_register() - register a ccw driver
* @cdriver: driver to be registered
*
* This function is mainly a wrapper around driver_register().
* Returns:
* %0 on success and a negative error value on failure.
*/
int ccw_driver_register(struct ccw_driver *cdriver)
{
struct device_driver *drv = &cdriver->driver;
drv->bus = &ccw_bus_type;
drv->name = cdriver->name;
drv->owner = cdriver->owner;
return driver_register(drv);
}
/**
* ccw_driver_unregister() - deregister a ccw driver
* @cdriver: driver to be deregistered
*
* This function is mainly a wrapper around driver_unregister().
*/
void ccw_driver_unregister(struct ccw_driver *cdriver)
{
driver_unregister(&cdriver->driver);
}
/* Helper func for qdio. */
struct subchannel_id
ccw_device_get_subchannel_id(struct ccw_device *cdev)
{
struct subchannel *sch;
sch = to_subchannel(cdev->dev.parent);
return sch->schid;
}
MODULE_LICENSE("GPL");
EXPORT_SYMBOL(ccw_device_set_online);
EXPORT_SYMBOL(ccw_device_set_offline);
EXPORT_SYMBOL(ccw_driver_register);
EXPORT_SYMBOL(ccw_driver_unregister);
EXPORT_SYMBOL(get_ccwdev_by_busid);
EXPORT_SYMBOL(ccw_bus_type);
EXPORT_SYMBOL(ccw_device_work);
EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);
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