From b898320d683d54c2bc17b748b9742d2b601ad453 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Fri, 27 Feb 2015 17:58:42 -0500 Subject: [PATCH] dm sysfs: introduce ability to add writable attributes Add DM_ATTR_RW() macro and establish .store method in dm_sysfs_ops. Signed-off-by: Mike Snitzer --- drivers/md/dm-sysfs.c | 32 +++++++++++++++++++++++++++----- 1 file changed, 27 insertions(+), 5 deletions(-) diff --git a/drivers/md/dm-sysfs.c b/drivers/md/dm-sysfs.c index c62c5ab6aed5..1271c31709fd 100644 --- a/drivers/md/dm-sysfs.c +++ b/drivers/md/dm-sysfs.c @@ -11,7 +11,7 @@ struct dm_sysfs_attr { struct attribute attr; ssize_t (*show)(struct mapped_device *, char *); - ssize_t (*store)(struct mapped_device *, char *); + ssize_t (*store)(struct mapped_device *, const char *, size_t count); }; #define DM_ATTR_RO(_name) \ @@ -39,6 +39,31 @@ static ssize_t dm_attr_show(struct kobject *kobj, struct attribute *attr, return ret; } +#define DM_ATTR_RW(_name) \ +struct dm_sysfs_attr dm_attr_##_name = \ + __ATTR(_name, S_IRUGO | S_IWUSR, dm_attr_##_name##_show, dm_attr_##_name##_store) + +static ssize_t dm_attr_store(struct kobject *kobj, struct attribute *attr, + const char *page, size_t count) +{ + 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->store) + return -EIO; + + md = dm_get_from_kobject(kobj); + if (!md) + return -EINVAL; + + ret = dm_attr->store(md, page, count); + 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)) @@ -77,12 +102,9 @@ static struct attribute *dm_attrs[] = { static const struct sysfs_ops dm_sysfs_ops = { .show = dm_attr_show, + .store = dm_attr_store, }; -/* - * 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,