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 31static 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 37static 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 43static ssize_t super_blocks_used_show(struct btrfs_fs_info *fs, char *buf) 44{ 45 46 return snprintf(buf, PAGE_SIZE, "%llu\n", 47 (unsigned long long)btrfs_super_bytes_used(&fs->super_copy)); 48} 49 50static ssize_t super_total_blocks_show(struct btrfs_fs_info *fs, char *buf) 51{ 52 return snprintf(buf, PAGE_SIZE, "%llu\n", 53 (unsigned long long)btrfs_super_total_bytes(&fs->super_copy)); 54} 55 56static ssize_t super_blocksize_show(struct btrfs_fs_info *fs, char *buf) 57{ 58 return snprintf(buf, PAGE_SIZE, "%llu\n", 59 (unsigned long long)btrfs_super_sectorsize(&fs->super_copy)); 60} 61 62/* this is for root attrs (subvols/snapshots) */ 63struct btrfs_root_attr { 64 struct attribute attr; 65 ssize_t (*show)(struct btrfs_root *, char *); 66 ssize_t (*store)(struct btrfs_root *, const char *, size_t); 67}; 68 69#define ROOT_ATTR(name, mode, show, store) \ 70static struct btrfs_root_attr btrfs_root_attr_##name = __ATTR(name, mode, \ 71 show, store) 72 73ROOT_ATTR(blocks_used, 0444, root_blocks_used_show, NULL); 74ROOT_ATTR(block_limit, 0644, root_block_limit_show, NULL); 75 76static struct attribute *btrfs_root_attrs[] = { 77 &btrfs_root_attr_blocks_used.attr, 78 &btrfs_root_attr_block_limit.attr, 79 NULL, 80}; 81 82/* this is for super attrs (actual full fs) */ 83struct btrfs_super_attr { 84 struct attribute attr; 85 ssize_t (*show)(struct btrfs_fs_info *, char *); 86 ssize_t (*store)(struct btrfs_fs_info *, const char *, size_t); 87}; 88 89#define SUPER_ATTR(name, mode, show, store) \ 90static struct btrfs_super_attr btrfs_super_attr_##name = __ATTR(name, mode, \ 91 show, store) 92 93SUPER_ATTR(blocks_used, 0444, super_blocks_used_show, NULL); 94SUPER_ATTR(total_blocks, 0444, super_total_blocks_show, NULL); 95SUPER_ATTR(blocksize, 0444, super_blocksize_show, NULL); 96 97static struct attribute *btrfs_super_attrs[] = { 98 &btrfs_super_attr_blocks_used.attr, 99 &btrfs_super_attr_total_blocks.attr, 100 &btrfs_super_attr_blocksize.attr, 101 NULL, 102}; 103 104static ssize_t btrfs_super_attr_show(struct kobject *kobj, 105 struct attribute *attr, char *buf) 106{ 107 struct btrfs_fs_info *fs = container_of(kobj, struct btrfs_fs_info, 108 super_kobj); 109 struct btrfs_super_attr *a = container_of(attr, 110 struct btrfs_super_attr, 111 attr); 112 113 return a->show ? a->show(fs, buf) : 0; 114} 115 116static ssize_t btrfs_super_attr_store(struct kobject *kobj, 117 struct attribute *attr, 118 const char *buf, size_t len) 119{ 120 struct btrfs_fs_info *fs = container_of(kobj, struct btrfs_fs_info, 121 super_kobj); 122 struct btrfs_super_attr *a = container_of(attr, 123 struct btrfs_super_attr, 124 attr); 125 126 return a->store ? a->store(fs, buf, len) : 0; 127} 128 129static ssize_t btrfs_root_attr_show(struct kobject *kobj, 130 struct attribute *attr, char *buf) 131{ 132 struct btrfs_root *root = container_of(kobj, struct btrfs_root, 133 root_kobj); 134 struct btrfs_root_attr *a = container_of(attr, 135 struct btrfs_root_attr, 136 attr); 137 138 return a->show ? a->show(root, buf) : 0; 139} 140 141static ssize_t btrfs_root_attr_store(struct kobject *kobj, 142 struct attribute *attr, 143 const char *buf, size_t len) 144{ 145 struct btrfs_root *root = container_of(kobj, struct btrfs_root, 146 root_kobj); 147 struct btrfs_root_attr *a = container_of(attr, 148 struct btrfs_root_attr, 149 attr); 150 return a->store ? a->store(root, buf, len) : 0; 151} 152 153static void btrfs_super_release(struct kobject *kobj) 154{ 155 struct btrfs_fs_info *fs = container_of(kobj, struct btrfs_fs_info, 156 super_kobj); 157 complete(&fs->kobj_unregister); 158} 159 160static void btrfs_root_release(struct kobject *kobj) 161{ 162 struct btrfs_root *root = container_of(kobj, struct btrfs_root, 163 root_kobj); 164 complete(&root->kobj_unregister); 165} 166 167static const struct sysfs_ops btrfs_super_attr_ops = { 168 .show = btrfs_super_attr_show, 169 .store = btrfs_super_attr_store, 170}; 171 172static const struct sysfs_ops btrfs_root_attr_ops = { 173 .show = btrfs_root_attr_show, 174 .store = btrfs_root_attr_store, 175}; 176 177static struct kobj_type btrfs_root_ktype = { 178 .default_attrs = btrfs_root_attrs, 179 .sysfs_ops = &btrfs_root_attr_ops, 180 .release = btrfs_root_release, 181}; 182 183static struct kobj_type btrfs_super_ktype = { 184 .default_attrs = btrfs_super_attrs, 185 .sysfs_ops = &btrfs_super_attr_ops, 186 .release = btrfs_super_release, 187}; 188 189/* /sys/fs/btrfs/ entry */ 190static struct kset *btrfs_kset; 191 192int btrfs_sysfs_add_super(struct btrfs_fs_info *fs) 193{ 194 int error; 195 char *name; 196 char c; 197 int len = strlen(fs->sb->s_id) + 1; 198 int i; 199 200 name = kmalloc(len, GFP_NOFS); 201 if (!name) { 202 error = -ENOMEM; 203 goto fail; 204 } 205 206 for (i = 0; i < len; i++) { 207 c = fs->sb->s_id[i]; 208 if (c == '/' || c == '\\') 209 c = '!'; 210 name[i] = c; 211 } 212 name[len] = '\0'; 213 214 fs->super_kobj.kset = btrfs_kset; 215 error = kobject_init_and_add(&fs->super_kobj, &btrfs_super_ktype, 216 NULL, "%s", name); 217 kfree(name); 218 if (error) 219 goto fail; 220 221 return 0; 222 223fail: 224 printk(KERN_ERR "btrfs: sysfs creation for super failed\n"); 225 return error; 226} 227 228int btrfs_sysfs_add_root(struct btrfs_root *root) 229{ 230 int error; 231 232 error = kobject_init_and_add(&root->root_kobj, &btrfs_root_ktype, 233 &root->fs_info->super_kobj, 234 "%s", root->name); 235 if (error) 236 goto fail; 237 238 return 0; 239 240fail: 241 printk(KERN_ERR "btrfs: sysfs creation for root failed\n"); 242 return error; 243} 244 245void btrfs_sysfs_del_root(struct btrfs_root *root) 246{ 247 kobject_put(&root->root_kobj); 248 wait_for_completion(&root->kobj_unregister); 249} 250 251void btrfs_sysfs_del_super(struct btrfs_fs_info *fs) 252{ 253 kobject_put(&fs->super_kobj); 254 wait_for_completion(&fs->kobj_unregister); 255} 256 257int btrfs_init_sysfs(void) 258{ 259 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj); 260 if (!btrfs_kset) 261 return -ENOMEM; 262 return 0; 263} 264 265void btrfs_exit_sysfs(void) 266{ 267 kset_unregister(btrfs_kset); 268} 269