1/* 2 * Copyright (C) 2008 Red Hat, Inc. All rights reserved. 3 * 4 * This file is released under the GPL. 5 */ 6 7#include <linux/sysfs.h> 8#include <linux/dm-ioctl.h> 9#include "dm.h" 10 11struct dm_sysfs_attr { 12 struct attribute attr; 13 ssize_t (*show)(struct mapped_device *, char *); 14 ssize_t (*store)(struct mapped_device *, char *); 15}; 16 17#define DM_ATTR_RO(_name) \ 18struct dm_sysfs_attr dm_attr_##_name = \ 19 __ATTR(_name, S_IRUGO, dm_attr_##_name##_show, NULL) 20 21static ssize_t dm_attr_show(struct kobject *kobj, struct attribute *attr, 22 char *page) 23{ 24 struct dm_sysfs_attr *dm_attr; 25 struct mapped_device *md; 26 ssize_t ret; 27 28 dm_attr = container_of(attr, struct dm_sysfs_attr, attr); 29 if (!dm_attr->show) 30 return -EIO; 31 32 md = dm_get_from_kobject(kobj); 33 if (!md) 34 return -EINVAL; 35 36 ret = dm_attr->show(md, page); 37 dm_put(md); 38 39 return ret; 40} 41 42static ssize_t dm_attr_name_show(struct mapped_device *md, char *buf) 43{ 44 if (dm_copy_name_and_uuid(md, buf, NULL)) 45 return -EIO; 46 47 strcat(buf, "\n"); 48 return strlen(buf); 49} 50 51static ssize_t dm_attr_uuid_show(struct mapped_device *md, char *buf) 52{ 53 if (dm_copy_name_and_uuid(md, NULL, buf)) 54 return -EIO; 55 56 strcat(buf, "\n"); 57 return strlen(buf); 58} 59 60static ssize_t dm_attr_suspended_show(struct mapped_device *md, char *buf) 61{ 62 sprintf(buf, "%d\n", dm_suspended_md(md)); 63 64 return strlen(buf); 65} 66 67static DM_ATTR_RO(name); 68static DM_ATTR_RO(uuid); 69static DM_ATTR_RO(suspended); 70 71static struct attribute *dm_attrs[] = { 72 &dm_attr_name.attr, 73 &dm_attr_uuid.attr, 74 &dm_attr_suspended.attr, 75 NULL, 76}; 77 78static const struct sysfs_ops dm_sysfs_ops = { 79 .show = dm_attr_show, 80}; 81 82/* 83 * dm kobject is embedded in mapped_device structure 84 * no need to define release function here 85 */ 86static struct kobj_type dm_ktype = { 87 .sysfs_ops = &dm_sysfs_ops, 88 .default_attrs = dm_attrs, 89}; 90 91/* 92 * Initialize kobj 93 * because nobody using md yet, no need to call explicit dm_get/put 94 */ 95int dm_sysfs_init(struct mapped_device *md) 96{ 97 return kobject_init_and_add(dm_kobject(md), &dm_ktype, 98 &disk_to_dev(dm_disk(md))->kobj, 99 "%s", "dm"); 100} 101 102/* 103 * Remove kobj, called after all references removed 104 */ 105void dm_sysfs_exit(struct mapped_device *md) 106{ 107 kobject_put(dm_kobject(md)); 108} 109