Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
sys.c
Go to the documentation of this file.
1 /*
2  * Copyright (C) 2012
3  * Sachin Bhamare <[email protected]>
4  * Boaz Harrosh <[email protected]>
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 <[email protected]>
20  */
21 
22 #include <linux/kobject.h>
23 #include <linux/device.h>
24 
25 #include "exofs.h"
26 
27 struct 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 
33 static 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 
42 static 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 
51 static const struct sysfs_ops odev_attr_ops = {
52  .show = odev_attr_show,
53  .store = odev_attr_store,
54 };
55 
56 
57 static struct kset *exofs_kset;
58 
59 static 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 
67 static 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 
76 static ssize_t uri_show(struct exofs_dev *edp, char *buf)
77 {
78  return snprintf(buf, edp->urilen, "%s", edp->uri);
79 }
80 
81 static ssize_t uri_store(struct exofs_dev *edp, const char *buf, size_t len)
82 {
83  uint8_t *new_uri;
84 
85  edp->urilen = strlen(buf) + 1;
86  new_uri = krealloc(edp->uri, edp->urilen, GFP_KERNEL);
87  if (new_uri == NULL)
88  return -ENOMEM;
89  edp->uri = new_uri;
90  strncpy(edp->uri, buf, edp->urilen);
91  return edp->urilen;
92 }
93 
94 #define OSD_ATTR(name, mode, show, store) \
95  static struct odev_attr odev_attr_##name = \
96  __ATTR(name, mode, show, store)
97 
98 OSD_ATTR(osdname, S_IRUGO, osdname_show, NULL);
99 OSD_ATTR(systemid, S_IRUGO, systemid_show, NULL);
100 OSD_ATTR(uri, S_IRWXU, uri_show, uri_store);
101 
102 static struct attribute *odev_attrs[] = {
103  &odev_attr_osdname.attr,
104  &odev_attr_systemid.attr,
105  &odev_attr_uri.attr,
106  NULL,
107 };
108 
109 static struct kobj_type odev_ktype = {
110  .default_attrs = odev_attrs,
111  .sysfs_ops = &odev_attr_ops,
112 };
113 
114 static struct kobj_type uuid_ktype = {
115 };
116 
118 {
119 #ifdef CONFIG_EXOFS_DEBUG
120  struct kobject *k_name, *k_tmp;
121 
122  list_for_each_entry_safe(k_name, k_tmp, &exofs_kset->list, entry) {
123  printk(KERN_INFO "%s: name %s ref %d\n",
124  __func__, kobject_name(k_name),
125  (int)atomic_read(&k_name->kref.refcount));
126  }
127 #endif
128 }
129 /*
130  * This function removes all kobjects under exofs_kset
131  * At the end of it, exofs_kset kobject will have a refcount
132  * of 1 which gets decremented only on exofs module unload
133  */
135 {
136  struct kobject *k_name, *k_tmp;
137  struct kobject *s_kobj = &sbi->s_kobj;
138 
139  list_for_each_entry_safe(k_name, k_tmp, &exofs_kset->list, entry) {
140  /* Remove all that are children of this SBI */
141  if (k_name->parent == s_kobj)
142  kobject_put(k_name);
143  }
144  kobject_put(s_kobj);
145 }
146 
147 /*
148  * This function creates sysfs entries to hold the current exofs cluster
149  * instance (uniquely identified by osdname,pid tuple).
150  * This function gets called once per exofs mount instance.
151  */
153  struct exofs_dt_device_info *dt_dev)
154 {
155  struct kobject *s_kobj;
156  int retval = 0;
157  uint64_t pid = sbi->one_comp.obj.partition;
158 
159  /* allocate new uuid dirent */
160  s_kobj = &sbi->s_kobj;
161  s_kobj->kset = exofs_kset;
162  retval = kobject_init_and_add(s_kobj, &uuid_ktype,
163  &exofs_kset->kobj, "%s_%llx", dt_dev->osdname, pid);
164  if (retval) {
165  EXOFS_ERR("ERROR: Failed to create sysfs entry for "
166  "uuid-%s_%llx => %d\n", dt_dev->osdname, pid, retval);
167  return -ENOMEM;
168  }
169  return 0;
170 }
171 
172 int exofs_sysfs_odev_add(struct exofs_dev *edev, struct exofs_sb_info *sbi)
173 {
174  struct kobject *d_kobj;
175  int retval = 0;
176 
177  /* create osd device group which contains following attributes
178  * osdname, systemid & uri
179  */
180  d_kobj = &edev->ed_kobj;
181  d_kobj->kset = exofs_kset;
182  retval = kobject_init_and_add(d_kobj, &odev_ktype,
183  &sbi->s_kobj, "dev%u", edev->did);
184  if (retval) {
185  EXOFS_ERR("ERROR: Failed to create sysfs entry for "
186  "device dev%u\n", edev->did);
187  return retval;
188  }
189  return 0;
190 }
191 
193 {
194  exofs_kset = kset_create_and_add("exofs", NULL, fs_kobj);
195  if (!exofs_kset) {
196  EXOFS_ERR("ERROR: kset_create_and_add exofs failed\n");
197  return -ENOMEM;
198  }
199  return 0;
200 }
201 
203 {
204  kset_unregister(exofs_kset);
205 }