// SPDX-License-Identifier: GPL-2.0
/*
* Recognize and maintain s390 storage class memory.
*
* Copyright IBM Corp. 2012
* Author(s): Sebastian Ott <[email protected]>
*/
#include <linux/device.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/err.h>
#include <asm/eadm.h>
#include "chsc.h"
static struct device *scm_root;
#define to_scm_dev(n) container_of(n, struct scm_device, dev)
#define to_scm_drv(d) container_of(d, struct scm_driver, drv)
static int scmdev_probe(struct device *dev)
{
struct scm_device *scmdev = to_scm_dev(dev);
struct scm_driver *scmdrv = to_scm_drv(dev->driver);
return scmdrv->probe ? scmdrv->probe(scmdev) : -ENODEV;
}
static void scmdev_remove(struct device *dev)
{
struct scm_device *scmdev = to_scm_dev(dev);
struct scm_driver *scmdrv = to_scm_drv(dev->driver);
if (scmdrv->remove)
scmdrv->remove(scmdev);
}
static int scmdev_uevent(const struct device *dev, struct kobj_uevent_env *env)
{
return add_uevent_var(env, "MODALIAS=scm:scmdev");
}
static const struct bus_type scm_bus_type = {
.name = "scm",
.probe = scmdev_probe,
.remove = scmdev_remove,
.uevent = scmdev_uevent,
};
/**
* scm_driver_register() - register a scm driver
* @scmdrv: driver to be registered
*/
int scm_driver_register(struct scm_driver *scmdrv)
{
struct device_driver *drv = &scmdrv->drv;
drv->bus = &scm_bus_type;
return driver_register(drv);
}
EXPORT_SYMBOL_GPL(scm_driver_register);
/**
* scm_driver_unregister() - deregister a scm driver
* @scmdrv: driver to be deregistered
*/
void scm_driver_unregister(struct scm_driver *scmdrv)
{
driver_unregister(&scmdrv->drv);
}
EXPORT_SYMBOL_GPL(scm_driver_unregister);
void scm_irq_handler(struct aob *aob, blk_status_t error)
{
struct aob_rq_header *aobrq = (void *) aob->request.data;
struct scm_device *scmdev = aobrq->scmdev;
struct scm_driver *scmdrv = to_scm_drv(scmdev->dev.driver);
scmdrv->handler(scmdev, aobrq->data, error);
}
EXPORT_SYMBOL_GPL(scm_irq_handler);
#define scm_attr(name) \
static ssize_t show_##name(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct scm_device *scmdev = to_scm_dev(dev); \
int ret; \
\
device_lock(dev); \
ret = sprintf(buf, "%u\n", scmdev->attrs.name); \
device_unlock(dev); \
\
return ret; \
} \
static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL);
scm_attr(persistence);
scm_attr(oper_state);
scm_attr(data_state);
scm_attr(rank);
scm_attr(release);
scm_attr(res_id);
static struct attribute *scmdev_attrs[] = {
&dev_attr_persistence.attr,
&dev_attr_oper_state.attr,
&dev_attr_data_state.attr,
&dev_attr_rank.attr,
&dev_attr_release.attr,
&dev_attr_res_id.attr,
NULL,
};
static struct attribute_group scmdev_attr_group = {
.attrs = scmdev_attrs,
};
static const struct attribute_group *scmdev_attr_groups[] = {
&scmdev_attr_group,
NULL,
};
static void scmdev_release(struct device *dev)
{
struct scm_device *scmdev = to_scm_dev(dev);
kfree(scmdev);
}
static void scmdev_setup(struct scm_device *scmdev, struct sale *sale,
unsigned int size, unsigned int max_blk_count)
{
dev_set_name(&scmdev->dev, "%016llx", (unsigned long long) sale->sa);
scmdev->nr_max_block = max_blk_count;
scmdev->address = sale->sa;
scmdev->size = 1UL << size;
scmdev->attrs.rank = sale->rank;
scmdev->attrs.persistence = sale->p;
scmdev->attrs.oper_state = sale->op_state;
scmdev->attrs.data_state = sale->data_state;
scmdev->attrs.rank = sale->rank;
scmdev->attrs.release = sale->r;
scmdev->attrs.res_id = sale->rid;
scmdev->dev.parent = scm_root;
scmdev->dev.bus = &scm_bus_type;
scmdev->dev.release = scmdev_release;
scmdev->dev.groups = scmdev_attr_groups;
}
/*
* Check for state-changes, notify the driver and userspace.
*/
static void scmdev_update(struct scm_device *scmdev, struct sale *sale)
{
struct scm_driver *scmdrv;
bool changed;
device_lock(&scmdev->dev);
changed = scmdev->attrs.rank != sale->rank ||
scmdev->attrs.oper_state != sale->op_state;
scmdev->attrs.rank = sale->rank;
scmdev->attrs.oper_state = sale->op_state;
if (!scmdev->dev.driver)
goto out;
scmdrv = to_scm_drv(scmdev->dev.driver);
if (changed && scmdrv->notify)
scmdrv->notify(scmdev, SCM_CHANGE);
out:
device_unlock(&scmdev->dev);
if (changed)
kobject_uevent(&scmdev->dev.kobj, KOBJ_CHANGE);
}
static int check_address(struct device *dev, const void *data)
{
struct scm_device *scmdev = to_scm_dev(dev);
const struct sale *sale = data;
return scmdev->address == sale->sa;
}
static struct scm_device *scmdev_find(struct sale *sale)
{
struct device *dev;
dev = bus_find_device(&scm_bus_type, NULL, sale, check_address);
return dev ? to_scm_dev(dev) : NULL;
}
static int scm_add(struct chsc_scm_info *scm_info, size_t num)
{
struct sale *sale, *scmal = scm_info->scmal;
struct scm_device *scmdev;
int ret;
for (sale = scmal; sale < scmal + num; sale++) {
scmdev = scmdev_find(sale);
if (scmdev) {
scmdev_update(scmdev, sale);
/* Release reference from scm_find(). */
put_device(&scmdev->dev);
continue;
}
scmdev = kzalloc(sizeof(*scmdev), GFP_KERNEL);
if (!scmdev)
return -ENODEV;
scmdev_setup(scmdev, sale, scm_info->is, scm_info->mbc);
ret = device_register(&scmdev->dev);
if (ret) {
/* Release reference from device_initialize(). */
put_device(&scmdev->dev);
return ret;
}
}
return 0;
}
int scm_update_information(void)
{
struct chsc_scm_info *scm_info;
u64 token = 0;
size_t num;
int ret;
scm_info = (void *)__get_free_page(GFP_KERNEL);
if (!scm_info)
return -ENOMEM;
do {
ret = chsc_scm_info(scm_info, token);
if (ret)
break;
num = (scm_info->response.length -
(offsetof(struct chsc_scm_info, scmal) -
offsetof(struct chsc_scm_info, response))
) / sizeof(struct sale);
ret = scm_add(scm_info, num);
if (ret)
break;
token = scm_info->restok;
} while (token);
free_page((unsigned long)scm_info);
return ret;
}
static int scm_dev_avail(struct device *dev, void *unused)
{
struct scm_driver *scmdrv = to_scm_drv(dev->driver);
struct scm_device *scmdev = to_scm_dev(dev);
if (dev->driver && scmdrv->notify)
scmdrv->notify(scmdev, SCM_AVAIL);
return 0;
}
int scm_process_availability_information(void)
{
return bus_for_each_dev(&scm_bus_type, NULL, NULL, scm_dev_avail);
}
static int __init scm_init(void)
{
int ret;
ret = bus_register(&scm_bus_type);
if (ret)
return ret;
scm_root = root_device_register("scm");
if (IS_ERR(scm_root)) {
bus_unregister(&scm_bus_type);
return PTR_ERR(scm_root);
}
scm_update_information();
return 0;
}
subsys_initcall_sync(scm_init);
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