// 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(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); static void raid_component_release(struct device *dev) { struct raid_component *rc = container_of(dev, struct raid_component, dev); dev_printk(KERN_ERR, rc->dev.parent, "COMPONENT RELEASE\n"); put_device(rc->dev.parent); kfree(rc); } int raid_component_add(struct raid_template *r,struct device *raid_dev, struct device *component_dev) { struct device *cdev = attribute_container_find_class_device(&r->raid_attrs.ac, raid_dev); struct raid_component *rc; struct raid_data *rd = dev_get_drvdata(cdev); int err; rc = kzalloc(sizeof(*rc), GFP_KERNEL); if (!rc) return -ENOMEM; INIT_LIST_HEAD(&rc->node); device_initialize(&rc->dev); rc->dev.release = raid_component_release; rc->dev.parent = get_device(component_dev); rc->num = rd->component_count++; dev_set_name(&rc->dev, "component-%d", rc->num); list_add_tail(&rc->node, &rd->component_list); rc->dev.class = &raid_class.class; err = device_add(&rc->dev); if (err) goto err_out; return 0; err_out: list_del(&rc->node); rd->component_count--; put_device(component_dev); kfree(rc); return err; } EXPORT_SYMBOL(raid_component_add); 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);