// SPDX-License-Identifier: GPL-2.0-only
/*
* raid_class.c - implementation of a simple raid visualisation class
*
* Copyright (c) 2005 - James Bottomley <[email protected]>
*
* This class is designed to allow raid attributes to be visualised and
* manipulated in a form independent of the underlying raid. Ultimately this
* should work for both hardware and software raids.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/raid_class.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#define RAID_NUM_ATTRS 3
struct raid_internal {
struct raid_template r;
struct raid_function_template *f;
/* The actual attributes */
struct device_attribute private_attrs[RAID_NUM_ATTRS];
/* The array of null terminated pointers to attributes
* needed by scsi_sysfs.c */
struct device_attribute *attrs[RAID_NUM_ATTRS + 1];
};
struct raid_component {
struct list_head node;
struct device dev;
int num;
};
#define to_raid_internal(tmpl) container_of(tmpl, struct raid_internal, r)
#define tc_to_raid_internal(tcont) ({ \
struct raid_template *r = \
container_of(tcont, struct raid_template, raid_attrs); \
to_raid_internal(r); \
})
#define ac_to_raid_internal(acont) ({ \
struct transport_container *tc = \
container_of(acont, struct transport_container, ac); \
tc_to_raid_internal(tc); \
})
#define device_to_raid_internal(dev) ({ \
struct attribute_container *ac = \
attribute_container_classdev_to_container(dev); \
ac_to_raid_internal(ac); \
})
static int raid_match(struct attribute_container *cont, struct device *dev)
{
/* We have to look for every subsystem that could house
* emulated RAID devices, so start with SCSI */
struct raid_internal *i = ac_to_raid_internal(cont);
if (IS_ENABLED(CONFIG_SCSI) && scsi_is_sdev_device(dev)) {
struct scsi_device *sdev = to_scsi_device(dev);
if (i->f->cookie != sdev->host->hostt)
return 0;
return i->f->is_raid(dev);
}
/* FIXME: look at other subsystems too */
return 0;
}
static int raid_setup(struct transport_container *tc, struct device *dev,
struct device *cdev)
{
struct raid_data *rd;
BUG_ON(dev_get_drvdata(cdev));
rd = kzalloc(sizeof(*rd), GFP_KERNEL);
if (!rd)
return -ENOMEM;
INIT_LIST_HEAD(&rd->component_list);
dev_set_drvdata(cdev, rd);
return 0;
}
static int raid_remove(struct transport_container *tc, struct device *dev,
struct device *cdev)
{
struct raid_data *rd = dev_get_drvdata(cdev);
struct raid_component *rc, *next;
dev_printk(KERN_ERR, dev, "RAID REMOVE\n");
dev_set_drvdata(cdev, NULL);
list_for_each_entry_safe(rc, next, &rd->component_list, node) {
list_del(&rc->node);
dev_printk(KERN_ERR, rc->dev.parent, "RAID COMPONENT REMOVE\n");
device_unregister(&rc->dev);
}
dev_printk(KERN_ERR, dev, "RAID REMOVE DONE\n");
kfree(rd);
return 0;
}
static DECLARE_TRANSPORT_CLASS(raid_class,
"raid_devices",
raid_setup,
raid_remove,
NULL);
static const struct {
enum raid_state value;
char *name;
} raid_states[] = {
{ RAID_STATE_UNKNOWN, "unknown" },
{ RAID_STATE_ACTIVE, "active" },
{ RAID_STATE_DEGRADED, "degraded" },
{ RAID_STATE_RESYNCING, "resyncing" },
{ RAID_STATE_OFFLINE, "offline" },
};
static const char *raid_state_name(enum raid_state state)
{
int i;
char *name = NULL;
for (i = 0; i < ARRAY_SIZE(raid_states); i++) {
if (raid_states[i].value == state) {
name = raid_states[i].name;
break;
}
}
return name;
}
static struct {
enum raid_level value;
char *name;
} raid_levels[] = {
{ RAID_LEVEL_UNKNOWN, "unknown" },
{ RAID_LEVEL_LINEAR, "linear" },
{ RAID_LEVEL_0, "raid0" },
{ RAID_LEVEL_1, "raid1" },
{ RAID_LEVEL_10, "raid10" },
{ RAID_LEVEL_1E, "raid1e" },
{ RAID_LEVEL_3, "raid3" },
{ RAID_LEVEL_4, "raid4" },
{ RAID_LEVEL_5, "raid5" },
{ RAID_LEVEL_50, "raid50" },
{ RAID_LEVEL_6, "raid6" },
{ RAID_LEVEL_JBOD, "jbod" },
};
static const char *raid_level_name(enum raid_level level)
{
int i;
char *name = NULL;
for (i = 0; i < ARRAY_SIZE(raid_levels); i++) {
if (raid_levels[i].value == level) {
name = raid_levels[i].name;
break;
}
}
return name;
}
#define raid_attr_show_internal(attr, fmt, var, code) \
static ssize_t raid_show_##attr(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
{ \
struct raid_data *rd = dev_get_drvdata(dev); \
code \
return snprintf(buf, 20, #fmt "\n", var); \
}
#define raid_attr_ro_states(attr, states, code) \
raid_attr_show_internal(attr, %s, name, \
const char *name; \
code \
name = raid_##states##_name(rd->attr); \
) \
static DEVICE_ATTR(attr, S_IRUGO, raid_show_##attr, NULL)
#define raid_attr_ro_internal(attr, code) \
raid_attr_show_internal(attr, %d, rd->attr, code) \
static DEVICE_ATTR(attr, S_IRUGO, raid_show_##attr, NULL)
#define ATTR_CODE(attr) \
struct raid_internal *i = device_to_raid_internal(dev); \
if (i->f->get_##attr) \
i->f->get_##attr(dev->parent);
#define raid_attr_ro(attr) raid_attr_ro_internal(attr, )
#define raid_attr_ro_fn(attr) raid_attr_ro_internal(attr, ATTR_CODE(attr))
#define raid_attr_ro_state(attr) raid_attr_ro_states(attr, attr, )
#define raid_attr_ro_state_fn(attr) raid_attr_ro_states(attr, attr, ATTR_CODE(attr))
raid_attr_ro_state(level);
raid_attr_ro_fn(resync);
raid_attr_ro_state_fn(state);
struct raid_template *
raid_class_attach(struct raid_function_template *ft)
{
struct raid_internal *i = kzalloc(sizeof(struct raid_internal),
GFP_KERNEL);
int count = 0;
if (unlikely(!i))
return NULL;
i->f = ft;
i->r.raid_attrs.ac.class = &raid_class.class;
i->r.raid_attrs.ac.match = raid_match;
i->r.raid_attrs.ac.attrs = &i->attrs[0];
attribute_container_register(&i->r.raid_attrs.ac);
i->attrs[count++] = &dev_attr_level;
i->attrs[count++] = &dev_attr_resync;
i->attrs[count++] = &dev_attr_state;
i->attrs[count] = NULL;
BUG_ON(count > RAID_NUM_ATTRS);
return &i->r;
}
EXPORT_SYMBOL(raid_class_attach);
void
raid_class_release(struct raid_template *r)
{
struct raid_internal *i = to_raid_internal(r);
BUG_ON(attribute_container_unregister(&i->r.raid_attrs.ac));
kfree(i);
}
EXPORT_SYMBOL(raid_class_release);
static __init int raid_init(void)
{
return transport_class_register(&raid_class);
}
static __exit void raid_exit(void)
{
transport_class_unregister(&raid_class);
}
MODULE_AUTHOR("James Bottomley");
MODULE_DESCRIPTION("RAID device class");
MODULE_LICENSE("GPL");
module_init(raid_init);
module_exit(raid_exit);
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