linux/drivers/scsi/raid_class.c

251 lines
6.0 KiB
C

/*
* RAID Attributes
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/list.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 class_device_attribute private_attrs[RAID_NUM_ATTRS];
/* The array of null terminated pointers to attributes
* needed by scsi_sysfs.c */
struct class_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 class_device_to_raid_internal(cdev) ({ \
struct attribute_container *ac = \
attribute_container_classdev_to_container(cdev); \
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 (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 class_device *cdev)
{
struct raid_data *rd;
BUG_ON(class_get_devdata(cdev));
rd = kmalloc(sizeof(*rd), GFP_KERNEL);
if (!rd)
return -ENOMEM;
memset(rd, 0, sizeof(*rd));
INIT_LIST_HEAD(&rd->component_list);
class_set_devdata(cdev, rd);
return 0;
}
static int raid_remove(struct transport_container *tc, struct device *dev,
struct class_device *cdev)
{
struct raid_data *rd = class_get_devdata(cdev);
struct raid_component *rc, *next;
class_set_devdata(cdev, NULL);
list_for_each_entry_safe(rc, next, &rd->component_list, node) {
char buf[40];
snprintf(buf, sizeof(buf), "component-%d", rc->num);
list_del(&rc->node);
sysfs_remove_link(&cdev->kobj, buf);
kfree(rc);
}
kfree(class_get_devdata(cdev));
return 0;
}
static DECLARE_TRANSPORT_CLASS(raid_class,
"raid_devices",
raid_setup,
raid_remove,
NULL);
static struct {
enum raid_state value;
char *name;
} raid_states[] = {
{ RAID_ACTIVE, "active" },
{ RAID_DEGRADED, "degraded" },
{ RAID_RESYNCING, "resyncing" },
{ RAID_OFFLINE, "offline" },
};
static const char *raid_state_name(enum raid_state state)
{
int i;
char *name = NULL;
for (i = 0; i < sizeof(raid_states)/sizeof(raid_states[0]); i++) {
if (raid_states[i].value == state) {
name = raid_states[i].name;
break;
}
}
return name;
}
#define raid_attr_show_internal(attr, fmt, var, code) \
static ssize_t raid_show_##attr(struct class_device *cdev, char *buf) \
{ \
struct raid_data *rd = class_get_devdata(cdev); \
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 CLASS_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 CLASS_DEVICE_ATTR(attr, S_IRUGO, raid_show_##attr, NULL)
#define ATTR_CODE(attr) \
struct raid_internal *i = class_device_to_raid_internal(cdev); \
if (i->f->get_##attr) \
i->f->get_##attr(cdev->dev);
#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, ATTR_CODE(attr))
raid_attr_ro(level);
raid_attr_ro_fn(resync);
raid_attr_ro_state(state);
void raid_component_add(struct raid_template *r,struct device *raid_dev,
struct device *component_dev)
{
struct class_device *cdev =
attribute_container_find_class_device(&r->raid_attrs.ac,
raid_dev);
struct raid_component *rc;
struct raid_data *rd = class_get_devdata(cdev);
char buf[40];
rc = kmalloc(sizeof(*rc), GFP_KERNEL);
if (!rc)
return;
INIT_LIST_HEAD(&rc->node);
rc->dev = component_dev;
rc->num = rd->component_count++;
snprintf(buf, sizeof(buf), "component-%d", rc->num);
list_add_tail(&rc->node, &rd->component_list);
sysfs_create_link(&cdev->kobj, &component_dev->kobj, buf);
}
EXPORT_SYMBOL(raid_component_add);
struct raid_template *
raid_class_attach(struct raid_function_template *ft)
{
struct raid_internal *i = kmalloc(sizeof(struct raid_internal),
GFP_KERNEL);
int count = 0;
if (unlikely(!i))
return NULL;
memset(i, 0, sizeof(*i));
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++] = &class_device_attr_level;
i->attrs[count++] = &class_device_attr_resync;
i->attrs[count++] = &class_device_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);
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);