linux/drivers/s390/cio/device.c
Heiko Carstens a806170e29 [S390] Fix a lot of sparse warnings.
Most noteable part of this commit is the new local header file entry.h
which contains all the function declarations of functions that get only
called from asm code or are arch internal. That way we can avoid extern
declarations in C files.
This is more or less the same that was done for sparc64.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-17 07:47:06 +02:00

1589 lines
39 KiB
C

/*
* drivers/s390/cio/device.c
* bus driver for ccw devices
*
* Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
* IBM Corporation
* 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 "cio.h"
#include "cio_debug.h"
#include "css.h"
#include "device.h"
#include "ioasm.h"
#include "io_sch.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 int io_subchannel_notify(struct subchannel *, int);
static void io_subchannel_verify(struct subchannel *);
static void io_subchannel_ioterm(struct subchannel *);
static void io_subchannel_shutdown(struct subchannel *);
static struct css_driver io_subchannel_driver = {
.owner = THIS_MODULE,
.subchannel_type = SUBCHANNEL_TYPE_IO,
.name = "io_subchannel",
.irq = io_subchannel_irq,
.notify = io_subchannel_notify,
.verify = io_subchannel_verify,
.termination = io_subchannel_ioterm,
.probe = io_subchannel_probe,
.remove = io_subchannel_remove,
.shutdown = io_subchannel_shutdown,
};
struct workqueue_struct *ccw_device_work;
struct workqueue_struct *ccw_device_notify_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 ? */
ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
if (!ccw_device_notify_work) {
ret = -ENOMEM; /* FIXME: better errno ? */
goto out_err;
}
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 (ccw_device_notify_work)
destroy_workqueue(ccw_device_notify_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_notify_work);
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);
}
static void ccw_device_remove_orphan_cb(struct device *dev)
{
struct ccw_device *cdev = to_ccwdev(dev);
ccw_device_unregister(cdev);
put_device(&cdev->dev);
}
static void ccw_device_remove_sch_cb(struct device *dev)
{
struct subchannel *sch;
sch = to_subchannel(dev);
css_sch_device_unregister(sch);
/* Reset intparm to zeroes. */
sch->schib.pmcw.intparm = 0;
cio_modify(sch);
put_device(&sch->dev);
}
static void
ccw_device_remove_disconnected(struct ccw_device *cdev)
{
unsigned long flags;
int rc;
/*
* 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.
*/
spin_lock_irqsave(cdev->ccwlock, flags);
cdev->private->state = DEV_STATE_NOT_OPER;
spin_unlock_irqrestore(cdev->ccwlock, flags);
rc = device_schedule_callback(&cdev->dev,
ccw_device_remove_orphan_cb);
if (rc)
CIO_MSG_EVENT(2, "Couldn't unregister orphan "
"0.%x.%04x\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
return;
}
/* Deregister subchannel, which will kill the ccw device. */
rc = device_schedule_callback(cdev->dev.parent,
ccw_device_remove_sch_cb);
if (rc)
CIO_MSG_EVENT(2, "Couldn't unregister disconnected device "
"0.%x.%04x\n",
cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
}
/**
* 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);
ret = ccw_device_offline(cdev);
if (ret == -ENODEV) {
if (cdev->private->state != DEV_STATE_NOT_OPER) {
cdev->private->state = DEV_STATE_OFFLINE;
dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
}
spin_unlock_irq(cdev->ccwlock);
return ret;
}
spin_unlock_irq(cdev->ccwlock);
if (ret == 0)
wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
else {
CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
"device 0.%x.%04x\n",
ret, cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
cdev->online = 1;
}
return ret;
}
/**
* 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;
if (!cdev)
return -ENODEV;
if (cdev->online || !cdev->drv)
return -EINVAL;
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(2, "ccw_device_online returned %d, "
"device 0.%x.%04x\n",
ret, cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
return ret;
}
if (cdev->private->state != DEV_STATE_ONLINE)
return -ENODEV;
if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
cdev->online = 1;
return 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(2, "ccw_device_offline returned %d, "
"device 0.%x.%04x\n",
ret, cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
return (ret == 0) ? -ENODEV : ret;
}
static void online_store_handle_offline(struct ccw_device *cdev)
{
if (cdev->private->state == DEV_STATE_DISCONNECTED)
ccw_device_remove_disconnected(cdev);
else if (cdev->drv && cdev->drv->set_offline)
ccw_device_set_offline(cdev);
}
static int online_store_recog_and_online(struct ccw_device *cdev)
{
int ret;
/* Do device recognition, if needed. */
if (cdev->id.cu_type == 0) {
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->drv && cdev->drv->set_online)
ccw_device_set_online(cdev);
return 0;
}
static void online_store_handle_online(struct ccw_device *cdev, int force)
{
int ret;
ret = online_store_recog_and_online(cdev);
if (ret)
return;
if (force && cdev->private->state == DEV_STATE_BOXED) {
ret = ccw_device_stlck(cdev);
if (ret) {
dev_warn(&cdev->dev,
"ccw_device_stlck returned %d!\n", ret);
return;
}
if (cdev->id.cu_type == 0)
cdev->private->state = DEV_STATE_NOT_OPER;
online_store_recog_and_online(cdev);
}
}
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 i, force;
char *tmp;
if (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;
} else {
force = 0;
i = simple_strtoul(buf, &tmp, 16);
}
switch (i) {
case 0:
online_store_handle_offline(cdev);
break;
case 1:
online_store_handle_online(cdev, force);
break;
default:
count = -EINVAL;
}
if (cdev->drv)
module_put(cdev->drv->owner);
atomic_set(&cdev->private->onoff, 0);
return 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 * subch_attrs[] = {
&dev_attr_chpids.attr,
&dev_attr_pimpampom.attr,
NULL,
};
static struct attribute_group subch_attr_group = {
.attrs = subch_attrs,
};
struct attribute_group *subch_attr_groups[] = {
&subch_attr_group,
NULL,
};
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;
if ((ret = device_add(dev)))
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;
}
static void
ccw_device_add_changed(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;
if (device_add(&cdev->dev)) {
put_device(&cdev->dev);
return;
}
set_bit(1, &cdev->private->registered);
}
void ccw_device_do_unreg_rereg(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;
sch = to_subchannel(cdev->dev.parent);
ccw_device_unregister(cdev);
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_add_changed);
queue_work(ccw_device_work, &cdev->private->kick_work);
}
static void
ccw_device_release(struct device *dev)
{
struct ccw_device *cdev;
cdev = to_ccwdev(dev);
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)) {
if (cdev->dev.release)
cdev->dev.release(&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) {
kfree(cdev);
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;
device_trigger_reprobe(sch);
spin_unlock_irq(sch->lock);
}
static void sch_attach_disconnected_device(struct subchannel *sch,
struct ccw_device *cdev)
{
struct subchannel *other_sch;
int ret;
other_sch = to_subchannel(get_device(cdev->dev.parent));
ret = device_move(&cdev->dev, &sch->dev);
if (ret) {
CIO_MSG_EVENT(2, "Moving disconnected device 0.%x.%04x failed "
"(ret=%d)!\n", cdev->private->dev_id.ssid,
cdev->private->dev_id.devno, ret);
put_device(&other_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);
put_device(&other_sch->dev);
sch_attach_device(sch, cdev);
}
static void sch_attach_orphaned_device(struct subchannel *sch,
struct ccw_device *cdev)
{
int ret;
/* Try to move the ccw device to its new subchannel. */
ret = device_move(&cdev->dev, &sch->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);
return;
}
sch_attach_device(sch, cdev);
}
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);
if (cdev->dev.release)
cdev->dev.release(&cdev->dev);
css_sch_device_unregister(sch);
}
}
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;
/*
* Move the orphaned ccw device to the orphanage so the replacing
* ccw device can take its place on the subchannel.
*/
ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev);
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);
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);
return;
}
replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
if (replacing_cdev) {
sch_attach_orphaned_device(sch, replacing_cdev);
return;
}
sch_create_and_recog_new_device(sch);
}
/*
* 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);
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 (klist_node_attached(&cdev->dev.knode_parent)) {
if (!cdev->drv) {
ret = device_reprobe(&cdev->dev);
if (ret)
/* We can't do much here. */
CIO_MSG_EVENT(2, "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.
*/
sch->dev.uevent_suppress = 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);
put_device(&cdev->dev);
spin_lock_irqsave(sch->lock, flags);
sch_set_cdev(sch, NULL);
spin_unlock_irqrestore(sch->lock, flags);
kfree (cdev->private);
kfree (cdev);
put_device(&sch->dev);
if (atomic_dec_and_test(&ccw_device_init_count))
wake_up(&ccw_device_init_wq);
return;
}
put_device(&cdev->dev);
out:
cdev->private->flags.recog_done = 1;
put_device(&sch->dev);
wake_up(&cdev->private->wait_q);
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;
sch = to_subchannel(cdev->dev.parent);
css_sch_device_unregister(sch);
/* Reset intparm to zeroes. */
sch->schib.pmcw.intparm = 0;
cio_modify(sch);
put_device(&cdev->dev);
put_device(&sch->dev);
}
/*
* subchannel recognition done. Called from the state machine.
*/
void
io_subchannel_recog_done(struct ccw_device *cdev)
{
struct subchannel *sch;
if (css_init_done == 0) {
cdev->private->flags.recog_done = 1;
return;
}
switch (cdev->private->state) {
case DEV_STATE_NOT_OPER:
cdev->private->flags.recog_done = 1;
/* Remove device found not operational. */
if (!get_device(&cdev->dev))
break;
sch = to_subchannel(cdev->dev.parent);
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_call_sch_unregister);
queue_work(slow_path_wq, &cdev->private->kick_work);
if (atomic_dec_and_test(&ccw_device_init_count))
wake_up(&ccw_device_init_wq);
break;
case DEV_STATE_BOXED:
/* Device did not respond in time. */
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);
sch->driver = &io_subchannel_driver;
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);
/* Set an initial name for the device. */
snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
sch->schid.ssid, sch->schib.pmcw.dev);
/* 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 = ccw_device_is_orphan(cdev) ?
NULL : to_subchannel(get_device(cdev->dev.parent));
mutex_lock(&sch->reg_mutex);
/* Try to move the ccw device to its new subchannel. */
rc = device_move(&cdev->dev, &sch->dev);
mutex_unlock(&sch->reg_mutex);
if (rc) {
CIO_MSG_EVENT(2, "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);
goto out;
}
if (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->schib.pmcw.intparm = 0;
cio_modify(former_parent);
}
sch_attach_device(sch, cdev);
out:
if (former_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(3, "IRQ");
CIO_TRACE_EVENT(3, sch->dev.bus_id);
if (cdev)
dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
}
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) {
/*
* This subchannel already has an associated ccw_device.
* Register it and exit. This happens for all early
* device, e.g. the console.
*/
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
* (see ccw_device_online and css_init_done for the
* ugly details).
*/
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;
}
/*
* 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;
/* Allocate I/O subchannel private data. */
sch->private = kzalloc(sizeof(struct io_subchannel_private),
GFP_KERNEL | GFP_DMA);
if (!sch->private)
return -ENOMEM;
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)) {
kfree(sch->private);
return PTR_ERR(cdev);
}
rc = io_subchannel_recog(cdev, sch);
if (rc) {
spin_lock_irqsave(sch->lock, flags);
sch_set_cdev(sch, NULL);
spin_unlock_irqrestore(sch->lock, flags);
if (cdev->dev.release)
cdev->dev.release(&cdev->dev);
kfree(sch->private);
}
return rc;
}
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);
put_device(&cdev->dev);
kfree(sch->private);
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;
if (!cdev->drv)
return 0;
if (!cdev->online)
return 0;
return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
}
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 void io_subchannel_ioterm(struct subchannel *sch)
{
struct ccw_device *cdev;
cdev = sch_get_cdev(sch);
if (!cdev)
return;
/* Internal I/O will be retried by the interrupt handler. */
if (cdev->private->flags.intretry)
return;
cdev->private->state = DEV_STATE_CLEAR_VERIFY;
if (cdev->handler)
cdev->handler(cdev, cdev->private->intparm,
ERR_PTR(-EIO));
}
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);
}
#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));
/* 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;
}
#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 (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 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
//FIXME: we can't fail!
CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
"device 0.%x.%04x\n",
ret, cdev->private->dev_id.ssid,
cdev->private->dev_id.devno);
}
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);
}
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,
};
/**
* 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;
}
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(2, "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);
}
void ccw_device_schedule_recovery(void)
{
unsigned long flags;
CIO_MSG_EVENT(2, "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);
}
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(ccw_device_notify_work);
EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);