diff options
Diffstat (limited to 'drivers/md/dm-sysfs.c')
-rw-r--r-- | drivers/md/dm-sysfs.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/drivers/md/dm-sysfs.c b/drivers/md/dm-sysfs.c new file mode 100644 index 00000000000..a2a45e6c7c8 --- /dev/null +++ b/drivers/md/dm-sysfs.c @@ -0,0 +1,99 @@ +/* + * Copyright (C) 2008 Red Hat, Inc. All rights reserved. + * + * This file is released under the GPL. + */ + +#include <linux/sysfs.h> +#include <linux/dm-ioctl.h> +#include "dm.h" + +struct dm_sysfs_attr { + struct attribute attr; + ssize_t (*show)(struct mapped_device *, char *); + ssize_t (*store)(struct mapped_device *, char *); +}; + +#define DM_ATTR_RO(_name) \ +struct dm_sysfs_attr dm_attr_##_name = \ + __ATTR(_name, S_IRUGO, dm_attr_##_name##_show, NULL) + +static ssize_t dm_attr_show(struct kobject *kobj, struct attribute *attr, + char *page) +{ + struct dm_sysfs_attr *dm_attr; + struct mapped_device *md; + ssize_t ret; + + dm_attr = container_of(attr, struct dm_sysfs_attr, attr); + if (!dm_attr->show) + return -EIO; + + md = dm_get_from_kobject(kobj); + if (!md) + return -EINVAL; + + ret = dm_attr->show(md, page); + dm_put(md); + + return ret; +} + +static ssize_t dm_attr_name_show(struct mapped_device *md, char *buf) +{ + if (dm_copy_name_and_uuid(md, buf, NULL)) + return -EIO; + + strcat(buf, "\n"); + return strlen(buf); +} + +static ssize_t dm_attr_uuid_show(struct mapped_device *md, char *buf) +{ + if (dm_copy_name_and_uuid(md, NULL, buf)) + return -EIO; + + strcat(buf, "\n"); + return strlen(buf); +} + +static DM_ATTR_RO(name); +static DM_ATTR_RO(uuid); + +static struct attribute *dm_attrs[] = { + &dm_attr_name.attr, + &dm_attr_uuid.attr, + NULL, +}; + +static struct sysfs_ops dm_sysfs_ops = { + .show = dm_attr_show, +}; + +/* + * dm kobject is embedded in mapped_device structure + * no need to define release function here + */ +static struct kobj_type dm_ktype = { + .sysfs_ops = &dm_sysfs_ops, + .default_attrs = dm_attrs, +}; + +/* + * Initialize kobj + * because nobody using md yet, no need to call explicit dm_get/put + */ +int dm_sysfs_init(struct mapped_device *md) +{ + return kobject_init_and_add(dm_kobject(md), &dm_ktype, + &disk_to_dev(dm_disk(md))->kobj, + "%s", "dm"); +} + +/* + * Remove kobj, called after all references removed + */ +void dm_sysfs_exit(struct mapped_device *md) +{ + kobject_put(dm_kobject(md)); +} |