| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 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 | |
| 11 | struct 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) \ |
| 18 | struct dm_sysfs_attr dm_attr_##_name = \ |
| 19 | __ATTR(_name, S_IRUGO, dm_attr_##_name##_show, NULL) |
| 20 | |
| 21 | static 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 | |
| 42 | static 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 | |
| 51 | static 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 | |
| 60 | static 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 | |
| 67 | static DM_ATTR_RO(name); |
| 68 | static DM_ATTR_RO(uuid); |
| 69 | static DM_ATTR_RO(suspended); |
| 70 | |
| 71 | static struct attribute *dm_attrs[] = { |
| 72 | &dm_attr_name.attr, |
| 73 | &dm_attr_uuid.attr, |
| 74 | &dm_attr_suspended.attr, |
| 75 | NULL, |
| 76 | }; |
| 77 | |
| 78 | static 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 | */ |
| 86 | static struct kobj_type dm_ktype = { |
| 87 | .sysfs_ops = &dm_sysfs_ops, |
| 88 | .default_attrs = dm_attrs, |
| 89 | .release = dm_kobject_release, |
| 90 | }; |
| 91 | |
| 92 | /* |
| 93 | * Initialize kobj |
| 94 | * because nobody using md yet, no need to call explicit dm_get/put |
| 95 | */ |
| 96 | int dm_sysfs_init(struct mapped_device *md) |
| 97 | { |
| 98 | return kobject_init_and_add(dm_kobject(md), &dm_ktype, |
| 99 | &disk_to_dev(dm_disk(md))->kobj, |
| 100 | "%s", "dm"); |
| 101 | } |
| 102 | |
| 103 | /* |
| 104 | * Remove kobj, called after all references removed |
| 105 | */ |
| 106 | void dm_sysfs_exit(struct mapped_device *md) |
| 107 | { |
| 108 | struct kobject *kobj = dm_kobject(md); |
| 109 | kobject_put(kobj); |
| 110 | wait_for_completion(dm_get_completion_from_kobject(kobj)); |
| 111 | } |