1/*
  2 * Copyright (C) 2012
  3 * Sachin Bhamare <sbhamare@panasas.com>
  4 * Boaz Harrosh <bharrosh@panasas.com>
  5 *
  6 * This file is part of exofs.
  7 *
  8 * exofs is free software; you can redistribute it and/or modify
  9 * it under the terms of the GNU General Public License 2 as published by
 10 * the Free Software Foundation.
 11 *
 12 * exofs is distributed in the hope that it will be useful,
 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15 * GNU General Public License for more details.
 16 *
 17 * You should have received a copy of the GNU General Public License
 18 * along with exofs; if not, write to the:
 19 *	Free Software Foundation <licensing@fsf.org>
 20 */
 21
 22#include <linux/kobject.h>
 23#include <linux/device.h>
 24
 25#include "exofs.h"
 26
 27struct odev_attr {
 28	struct attribute attr;
 29	ssize_t (*show)(struct exofs_dev *, char *);
 30	ssize_t (*store)(struct exofs_dev *, const char *, size_t);
 31};
 32
 33static ssize_t odev_attr_show(struct kobject *kobj, struct attribute *attr,
 34		char *buf)
 35{
 36	struct exofs_dev *edp = container_of(kobj, struct exofs_dev, ed_kobj);
 37	struct odev_attr *a = container_of(attr, struct odev_attr, attr);
 38
 39	return a->show ? a->show(edp, buf) : 0;
 40}
 41
 42static ssize_t odev_attr_store(struct kobject *kobj, struct attribute *attr,
 43		const char *buf, size_t len)
 44{
 45	struct exofs_dev *edp = container_of(kobj, struct exofs_dev, ed_kobj);
 46	struct odev_attr *a = container_of(attr, struct odev_attr, attr);
 47
 48	return a->store ? a->store(edp, buf, len) : len;
 49}
 50
 51static const struct sysfs_ops odev_attr_ops = {
 52	.show  = odev_attr_show,
 53	.store = odev_attr_store,
 54};
 55
 56
 57static struct kset *exofs_kset;
 58
 59static ssize_t osdname_show(struct exofs_dev *edp, char *buf)
 60{
 61	struct osd_dev *odev = edp->ored.od;
 62	const struct osd_dev_info *odi = osduld_device_info(odev);
 63
 64	return snprintf(buf, odi->osdname_len + 1, "%s", odi->osdname);
 65}
 66
 67static ssize_t systemid_show(struct exofs_dev *edp, char *buf)
 68{
 69	struct osd_dev *odev = edp->ored.od;
 70	const struct osd_dev_info *odi = osduld_device_info(odev);
 71
 72	memcpy(buf, odi->systemid, odi->systemid_len);
 73	return odi->systemid_len;
 74}
 75
 76static ssize_t uri_show(struct exofs_dev *edp, char *buf)
 77{
 78	return snprintf(buf, edp->urilen, "%s", edp->uri);
 79}
 80
 81static ssize_t uri_store(struct exofs_dev *edp, const char *buf, size_t len)
 82{
 83	edp->urilen = strlen(buf) + 1;
 84	edp->uri = krealloc(edp->uri, edp->urilen, GFP_KERNEL);
 85	strncpy(edp->uri, buf, edp->urilen);
 86	return edp->urilen;
 87}
 88
 89#define OSD_ATTR(name, mode, show, store) \
 90	static struct odev_attr odev_attr_##name = \
 91					__ATTR(name, mode, show, store)
 92
 93OSD_ATTR(osdname, S_IRUGO, osdname_show, NULL);
 94OSD_ATTR(systemid, S_IRUGO, systemid_show, NULL);
 95OSD_ATTR(uri, S_IRWXU, uri_show, uri_store);
 96
 97static struct attribute *odev_attrs[] = {
 98	&odev_attr_osdname.attr,
 99	&odev_attr_systemid.attr,
100	&odev_attr_uri.attr,
101	NULL,
102};
103
104static struct kobj_type odev_ktype = {
105	.default_attrs	= odev_attrs,
106	.sysfs_ops	= &odev_attr_ops,
107};
108
109static struct kobj_type uuid_ktype = {
110};
111
112void exofs_sysfs_dbg_print(void)
113{
114#ifdef CONFIG_EXOFS_DEBUG
115	struct kobject *k_name, *k_tmp;
116
117	list_for_each_entry_safe(k_name, k_tmp, &exofs_kset->list, entry) {
118		printk(KERN_INFO "%s: name %s ref %d\n",
119			__func__, kobject_name(k_name),
120			(int)atomic_read(&k_name->kref.refcount));
121	}
122#endif
123}
124/*
125 * This function removes all kobjects under exofs_kset
126 * At the end of it, exofs_kset kobject will have a refcount
127 * of 1 which gets decremented only on exofs module unload
128 */
129void exofs_sysfs_sb_del(struct exofs_sb_info *sbi)
130{
131	struct kobject *k_name, *k_tmp;
132	struct kobject *s_kobj = &sbi->s_kobj;
133
134	list_for_each_entry_safe(k_name, k_tmp, &exofs_kset->list, entry) {
135		/* Remove all that are children of this SBI */
136		if (k_name->parent == s_kobj)
137			kobject_put(k_name);
138	}
139	kobject_put(s_kobj);
140}
141
142/*
143 * This function creates sysfs entries to hold the current exofs cluster
144 * instance (uniquely identified by osdname,pid tuple).
145 * This function gets called once per exofs mount instance.
146 */
147int exofs_sysfs_sb_add(struct exofs_sb_info *sbi,
148		       struct exofs_dt_device_info *dt_dev)
149{
150	struct kobject *s_kobj;
151	int retval = 0;
152	uint64_t pid = sbi->one_comp.obj.partition;
153
154	/* allocate new uuid dirent */
155	s_kobj = &sbi->s_kobj;
156	s_kobj->kset = exofs_kset;
157	retval = kobject_init_and_add(s_kobj, &uuid_ktype,
158			&exofs_kset->kobj,  "%s_%llx", dt_dev->osdname, pid);
159	if (retval) {
160		EXOFS_ERR("ERROR: Failed to create sysfs entry for "
161			  "uuid-%s_%llx => %d\n", dt_dev->osdname, pid, retval);
162		return -ENOMEM;
163	}
164	return 0;
165}
166
167int exofs_sysfs_odev_add(struct exofs_dev *edev, struct exofs_sb_info *sbi)
168{
169	struct kobject *d_kobj;
170	int retval = 0;
171
172	/* create osd device group which contains following attributes
173	 * osdname, systemid & uri
174	 */
175	d_kobj = &edev->ed_kobj;
176	d_kobj->kset = exofs_kset;
177	retval = kobject_init_and_add(d_kobj, &odev_ktype,
178			&sbi->s_kobj, "dev%u", edev->did);
179	if (retval) {
180		EXOFS_ERR("ERROR: Failed to create sysfs entry for "
181				"device dev%u\n", edev->did);
182		return retval;
183	}
184	return 0;
185}
186
187int exofs_sysfs_init(void)
188{
189	exofs_kset = kset_create_and_add("exofs", NULL, fs_kobj);
190	if (!exofs_kset) {
191		EXOFS_ERR("ERROR: kset_create_and_add exofs failed\n");
192		return -ENOMEM;
193	}
194	return 0;
195}
196
197void exofs_sysfs_uninit(void)
198{
199	kset_unregister(exofs_kset);
200}