// SPDX-License-Identifier: GPL-2.0-only/* * raid_class.c - implementation of a simple raid visualisation class * * Copyright (c) 2005 - James Bottomley <James.Bottomley@steeleye.com> * * 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_obj(*rd);	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_obj(struct raid_internal);	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); voidraid_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);