SAFE public projects git trees. - safe/jmp/linux-2.6/blob - fs/btrfs/sysfs.c

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #include <linux/sched.h>
  20 #include <linux/slab.h>
  21 #include <linux/spinlock.h>
  22 #include <linux/completion.h>
  23 #include <linux/buffer_head.h>
  24 #include <linux/module.h>
  25 #include <linux/kobject.h>
  26
  27 #include "ctree.h"
  28 #include "disk-io.h"
  29 #include "transaction.h"
  30
  31 static ssize_t root_blocks_used_show(struct btrfs_root *root, char *buf)
  32 {
  33         return snprintf(buf, PAGE_SIZE, "%llu\n",
  34                 (unsigned long long)btrfs_root_used(&root->root_item));
  35 }
  36
  37 static ssize_t root_block_limit_show(struct btrfs_root *root, char *buf)
  38 {
  39         return snprintf(buf, PAGE_SIZE, "%llu\n",
  40                 (unsigned long long)btrfs_root_limit(&root->root_item));
  41 }
  42
  43 static ssize_t super_blocks_used_show(struct btrfs_fs_info *fs, char *buf)
  44 {
  45         return snprintf(buf, PAGE_SIZE, "%llu\n",
  46                 (unsigned long long)btrfs_super_blocks_used(&fs->super_copy));
  47 }
  48
  49 static ssize_t super_total_blocks_show(struct btrfs_fs_info *fs, char *buf)
  50 {
  51         return snprintf(buf, PAGE_SIZE, "%llu\n",
  52                 (unsigned long long)btrfs_super_total_blocks(&fs->super_copy));
  53 }
  54
  55 static ssize_t super_blocksize_show(struct btrfs_fs_info *fs, char *buf)
  56 {
  57         return snprintf(buf, PAGE_SIZE, "%llu\n",
  58                 (unsigned long long)btrfs_super_sectorsize(&fs->super_copy));
  59 }
  60
  61 /* this is for root attrs (subvols/snapshots) */
  62 struct btrfs_root_attr {
  63         struct attribute attr;
  64         ssize_t (*show)(struct btrfs_root *, char *);
  65         ssize_t (*store)(struct btrfs_root *, const char *, size_t);
  66 };
  67
  68 #define ROOT_ATTR(name, mode, show, store) \
  69 static struct btrfs_root_attr btrfs_root_attr_##name = __ATTR(name, mode, show, store)
  70
  71 ROOT_ATTR(blocks_used,  0444,   root_blocks_used_show,  NULL);
  72 ROOT_ATTR(block_limit,  0644,   root_block_limit_show,  NULL);
  73
  74 static struct attribute *btrfs_root_attrs[] = {
  75         &btrfs_root_attr_blocks_used.attr,
  76         &btrfs_root_attr_block_limit.attr,
  77         NULL,
  78 };
  79
  80 /* this is for super attrs (actual full fs) */
  81 struct btrfs_super_attr {
  82         struct attribute attr;
  83         ssize_t (*show)(struct btrfs_fs_info *, char *);
  84         ssize_t (*store)(struct btrfs_fs_info *, const char *, size_t);
  85 };
  86
  87 #define SUPER_ATTR(name, mode, show, store) \
  88 static struct btrfs_super_attr btrfs_super_attr_##name = __ATTR(name, mode, show, store)
  89
  90 SUPER_ATTR(blocks_used,         0444,   super_blocks_used_show,         NULL);
  91 SUPER_ATTR(total_blocks,        0444,   super_total_blocks_show,        NULL);
  92 SUPER_ATTR(blocksize,           0444,   super_blocksize_show,           NULL);
  93
  94 static struct attribute *btrfs_super_attrs[] = {
  95         &btrfs_super_attr_blocks_used.attr,
  96         &btrfs_super_attr_total_blocks.attr,
  97         &btrfs_super_attr_blocksize.attr,
  98         NULL,
  99 };
 100
 101 static ssize_t btrfs_super_attr_show(struct kobject *kobj,
 102                                     struct attribute *attr, char *buf)
 103 {
 104         struct btrfs_fs_info *fs = container_of(kobj, struct btrfs_fs_info,
 105                                                 super_kobj);
 106         struct btrfs_super_attr *a = container_of(attr,
 107                                                   struct btrfs_super_attr,
 108                                                   attr);
 109
 110         return a->show ? a->show(fs, buf) : 0;
 111 }
 112
 113 static ssize_t btrfs_super_attr_store(struct kobject *kobj,
 114                                      struct attribute *attr,
 115                                      const char *buf, size_t len)
 116 {
 117         struct btrfs_fs_info *fs = container_of(kobj, struct btrfs_fs_info,
 118                                                 super_kobj);
 119         struct btrfs_super_attr *a = container_of(attr,
 120                                                   struct btrfs_super_attr,
 121                                                   attr);
 122
 123         return a->store ? a->store(fs, buf, len) : 0;
 124 }
 125
 126 static ssize_t btrfs_root_attr_show(struct kobject *kobj,
 127                                     struct attribute *attr, char *buf)
 128 {
 129         struct btrfs_root *root = container_of(kobj, struct btrfs_root,
 130                                                 root_kobj);
 131         struct btrfs_root_attr *a = container_of(attr,
 132                                                  struct btrfs_root_attr,
 133                                                  attr);
 134
 135         return a->show ? a->show(root, buf) : 0;
 136 }
 137
 138 static ssize_t btrfs_root_attr_store(struct kobject *kobj,
 139                                      struct attribute *attr,
 140                                      const char *buf, size_t len)
 141 {
 142         struct btrfs_root *root = container_of(kobj, struct btrfs_root,
 143                                                 root_kobj);
 144         struct btrfs_root_attr *a = container_of(attr,
 145                                                  struct btrfs_root_attr,
 146                                                  attr);
 147         return a->store ? a->store(root, buf, len) : 0;
 148 }
 149
 150 static void btrfs_super_release(struct kobject *kobj)
 151 {
 152         struct btrfs_fs_info *fs = container_of(kobj, struct btrfs_fs_info,
 153                                                 super_kobj);
 154         complete(&fs->kobj_unregister);
 155 }
 156
 157 static void btrfs_root_release(struct kobject *kobj)
 158 {
 159         struct btrfs_root *root = container_of(kobj, struct btrfs_root,
 160                                                 root_kobj);
 161         complete(&root->kobj_unregister);
 162 }
 163
 164 static struct sysfs_ops btrfs_super_attr_ops = {
 165         .show   = btrfs_super_attr_show,
 166         .store  = btrfs_super_attr_store,
 167 };
 168
 169 static struct sysfs_ops btrfs_root_attr_ops = {
 170         .show   = btrfs_root_attr_show,
 171         .store  = btrfs_root_attr_store,
 172 };
 173
 174 static struct kobj_type btrfs_root_ktype = {
 175         .default_attrs  = btrfs_root_attrs,
 176         .sysfs_ops      = &btrfs_root_attr_ops,
 177         .release        = btrfs_root_release,
 178 };
 179
 180 static struct kobj_type btrfs_super_ktype = {
 181         .default_attrs  = btrfs_super_attrs,
 182         .sysfs_ops      = &btrfs_super_attr_ops,
 183         .release        = btrfs_super_release,
 184 };
 185
 186 static struct kset btrfs_kset = {
 187         .kobj   = {.name = "btrfs"},
 188 };
 189
 190 int btrfs_sysfs_add_super(struct btrfs_fs_info *fs)
 191 {
 192         int error;
 193
 194         fs->super_kobj.kset = &btrfs_kset;
 195         fs->super_kobj.ktype = &btrfs_super_ktype;
 196
 197         error = kobject_set_name(&fs->super_kobj, "%s",
 198                                  fs->sb->s_id);
 199         if (error)
 200                 goto fail;
 201
 202         error = kobject_register(&fs->super_kobj);
 203         if (error)
 204                 goto fail;
 205
 206         return 0;
 207
 208 fail:
 209         printk(KERN_ERR "btrfs: sysfs creation for super failed\n");
 210         return error;
 211 }
 212
 213 int btrfs_sysfs_add_root(struct btrfs_root *root)
 214 {
 215         int error;
 216
 217         root->root_kobj.ktype = &btrfs_root_ktype;
 218         root->root_kobj.parent = &root->fs_info->super_kobj;
 219
 220         error = kobject_set_name(&root->root_kobj, "%s", root->name);
 221         if (error) {
 222                 goto fail;
 223         }
 224
 225         error = kobject_register(&root->root_kobj);
 226         if (error)
 227                 goto fail;
 228
 229         return 0;
 230
 231 fail:
 232         printk(KERN_ERR "btrfs: sysfs creation for root failed\n");
 233         return error;
 234 }
 235
 236 void btrfs_sysfs_del_root(struct btrfs_root *root)
 237 {
 238         kobject_unregister(&root->root_kobj);
 239         wait_for_completion(&root->kobj_unregister);
 240 }
 241
 242 void btrfs_sysfs_del_super(struct btrfs_fs_info *fs)
 243 {
 244         kobject_unregister(&fs->super_kobj);
 245         wait_for_completion(&fs->kobj_unregister);
 246 }
 247
 248 int btrfs_init_sysfs()
 249 {
 250         kobj_set_kset_s(&btrfs_kset, fs_subsys);
 251         return kset_register(&btrfs_kset);
 252 }
 253
 254 void btrfs_exit_sysfs()
 255 {
 256         kset_unregister(&btrfs_kset);
 257 }