blob: a7acfe639a449eeb278214a04bfc6037249e3048 [file] [log] [blame]
Chris Mason6cbd5572007-06-12 09:07:21 -04001/*
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
Yan4b82d6e2007-08-29 09:11:44 -040019#include <linux/blkdev.h>
Chris Mason2e635a22007-03-21 11:12:56 -040020#include <linux/module.h>
Chris Masone20d96d2007-03-22 12:13:20 -040021#include <linux/buffer_head.h>
Chris Mason2e635a22007-03-21 11:12:56 -040022#include <linux/fs.h>
23#include <linux/pagemap.h>
24#include <linux/highmem.h>
25#include <linux/time.h>
26#include <linux/init.h>
Eric Parisa9572a12009-04-02 16:46:06 -040027#include <linux/seq_file.h>
Chris Mason2e635a22007-03-21 11:12:56 -040028#include <linux/string.h>
29#include <linux/smp_lock.h>
30#include <linux/backing-dev.h>
Yan4b82d6e2007-08-29 09:11:44 -040031#include <linux/mount.h>
Chris Masondee26a92007-03-26 16:00:06 -040032#include <linux/mpage.h>
Chris Mason75dfe392007-03-29 11:56:46 -040033#include <linux/swap.h>
34#include <linux/writeback.h>
Chris Mason8fd17792007-04-19 21:01:03 -040035#include <linux/statfs.h>
Chris Mason08607c12007-06-08 15:33:54 -040036#include <linux/compat.h>
Chris Mason95e05282007-08-29 09:11:44 -040037#include <linux/parser.h>
Chris Masonc59f8952007-12-17 20:14:04 -050038#include <linux/ctype.h>
Chris Mason6da6aba2007-12-18 16:15:09 -050039#include <linux/namei.h>
Chris Masona9218f62008-03-24 15:02:04 -040040#include <linux/miscdevice.h>
Qinghuang Feng1bcbf312009-01-15 13:51:03 -080041#include <linux/magic.h>
Chris Mason4b4e25f2008-11-20 10:22:27 -050042#include "compat.h"
Chris Mason2e635a22007-03-21 11:12:56 -040043#include "ctree.h"
Chris Masone20d96d2007-03-22 12:13:20 -040044#include "disk-io.h"
Chris Masond5719762007-03-23 10:01:08 -040045#include "transaction.h"
Chris Mason2c90e5d2007-04-02 10:50:19 -040046#include "btrfs_inode.h"
Chris Masonc5739bb2007-04-10 09:27:04 -040047#include "ioctl.h"
Chris Mason3a686372007-05-24 13:35:57 -040048#include "print-tree.h"
Josef Bacik5103e942007-11-16 11:45:54 -050049#include "xattr.h"
Chris Mason8a4b83c2008-03-24 15:02:07 -040050#include "volumes.h"
Chris Masonb3c3da72008-07-23 12:12:13 -040051#include "version.h"
Balaji Raobe6e8dc2008-07-21 02:01:56 +053052#include "export.h"
Chris Masonc8b97812008-10-29 14:49:59 -040053#include "compression.h"
Chris Mason2e635a22007-03-21 11:12:56 -040054
Chris Masone20d96d2007-03-22 12:13:20 -040055
Chris Masone20d96d2007-03-22 12:13:20 -040056static struct super_operations btrfs_super_ops;
Chris Masone20d96d2007-03-22 12:13:20 -040057
Chris Masond3977122009-01-05 21:25:51 -050058static void btrfs_put_super(struct super_block *sb)
Chris Masone20d96d2007-03-22 12:13:20 -040059{
60 struct btrfs_root *root = btrfs_sb(sb);
61 int ret;
62
63 ret = close_ctree(root);
Chris Masone20d96d2007-03-22 12:13:20 -040064 sb->s_fs_info = NULL;
65}
Chris Mason2e635a22007-03-21 11:12:56 -040066
Chris Mason95e05282007-08-29 09:11:44 -040067enum {
Christoph Hellwig43e570b2008-06-10 10:40:46 -040068 Opt_degraded, Opt_subvol, Opt_device, Opt_nodatasum, Opt_nodatacow,
Chris Masondfe25022008-05-13 13:46:40 -040069 Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier,
Sage Weil3a5e1402009-04-02 16:49:40 -040070 Opt_ssd, Opt_thread_pool, Opt_noacl, Opt_compress, Opt_notreelog,
Sage Weildccae992009-04-02 16:59:01 -040071 Opt_flushoncommit, Opt_err,
Chris Mason95e05282007-08-29 09:11:44 -040072};
73
74static match_table_t tokens = {
Chris Masondfe25022008-05-13 13:46:40 -040075 {Opt_degraded, "degraded"},
Chris Mason95e05282007-08-29 09:11:44 -040076 {Opt_subvol, "subvol=%s"},
Christoph Hellwig43e570b2008-06-10 10:40:46 -040077 {Opt_device, "device=%s"},
Chris Masonb6cda9b2007-12-14 15:30:32 -050078 {Opt_nodatasum, "nodatasum"},
Chris Masonbe20aa92007-12-17 20:14:01 -050079 {Opt_nodatacow, "nodatacow"},
Chris Mason21ad10c2008-01-09 09:23:21 -050080 {Opt_nobarrier, "nobarrier"},
Chris Masonc59f8952007-12-17 20:14:04 -050081 {Opt_max_extent, "max_extent=%s"},
Chris Mason6f568d32008-01-29 16:03:38 -050082 {Opt_max_inline, "max_inline=%s"},
Chris Mason8f662a72008-01-02 10:01:11 -050083 {Opt_alloc_start, "alloc_start=%s"},
Chris Mason4543df72008-06-11 21:47:56 -040084 {Opt_thread_pool, "thread_pool=%d"},
Chris Masonc8b97812008-10-29 14:49:59 -040085 {Opt_compress, "compress"},
Chris Masone18e4802008-01-18 10:54:22 -050086 {Opt_ssd, "ssd"},
Josef Bacik33268ea2008-07-24 12:16:36 -040087 {Opt_noacl, "noacl"},
Sage Weil3a5e1402009-04-02 16:49:40 -040088 {Opt_notreelog, "notreelog"},
Sage Weildccae992009-04-02 16:59:01 -040089 {Opt_flushoncommit, "flushoncommit"},
Josef Bacik33268ea2008-07-24 12:16:36 -040090 {Opt_err, NULL},
Chris Mason95e05282007-08-29 09:11:44 -040091};
92
Chris Masonedbd8d42007-12-21 16:27:24 -050093u64 btrfs_parse_size(char *str)
Chris Masonc59f8952007-12-17 20:14:04 -050094{
Chris Masonedbd8d42007-12-21 16:27:24 -050095 u64 res;
Chris Masonc59f8952007-12-17 20:14:04 -050096 int mult = 1;
97 char *end;
98 char last;
99
100 res = simple_strtoul(str, &end, 10);
101
102 last = end[0];
103 if (isalpha(last)) {
104 last = tolower(last);
105 switch (last) {
106 case 'g':
107 mult *= 1024;
108 case 'm':
109 mult *= 1024;
110 case 'k':
111 mult *= 1024;
112 }
113 res = res * mult;
114 }
115 return res;
116}
117
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400118/*
119 * Regular mount options parser. Everything that is needed only when
120 * reading in a new superblock is parsed here.
121 */
122int btrfs_parse_options(struct btrfs_root *root, char *options)
Chris Mason95e05282007-08-29 09:11:44 -0400123{
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400124 struct btrfs_fs_info *info = root->fs_info;
Chris Mason95e05282007-08-29 09:11:44 -0400125 substring_t args[MAX_OPT_ARGS];
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400126 char *p, *num;
Chris Mason4543df72008-06-11 21:47:56 -0400127 int intarg;
Chris Masonb6cda9b2007-12-14 15:30:32 -0500128
Chris Mason95e05282007-08-29 09:11:44 -0400129 if (!options)
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400130 return 0;
Chris Mason95e05282007-08-29 09:11:44 -0400131
Chris Masonbe20aa92007-12-17 20:14:01 -0500132 /*
133 * strsep changes the string, duplicate it because parse_options
134 * gets called twice
135 */
136 options = kstrdup(options, GFP_NOFS);
137 if (!options)
138 return -ENOMEM;
139
Chris Masonbe20aa92007-12-17 20:14:01 -0500140
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400141 while ((p = strsep(&options, ",")) != NULL) {
Chris Mason95e05282007-08-29 09:11:44 -0400142 int token;
143 if (!*p)
144 continue;
145
146 token = match_token(p, tokens, args);
147 switch (token) {
Chris Masondfe25022008-05-13 13:46:40 -0400148 case Opt_degraded:
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400149 printk(KERN_INFO "btrfs: allowing degraded mounts\n");
150 btrfs_set_opt(info->mount_opt, DEGRADED);
Chris Masondfe25022008-05-13 13:46:40 -0400151 break;
Chris Mason95e05282007-08-29 09:11:44 -0400152 case Opt_subvol:
Christoph Hellwig43e570b2008-06-10 10:40:46 -0400153 case Opt_device:
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400154 /*
Christoph Hellwig43e570b2008-06-10 10:40:46 -0400155 * These are parsed by btrfs_parse_early_options
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400156 * and can be happily ignored here.
157 */
Chris Masonb6cda9b2007-12-14 15:30:32 -0500158 break;
159 case Opt_nodatasum:
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400160 printk(KERN_INFO "btrfs: setting nodatacsum\n");
161 btrfs_set_opt(info->mount_opt, NODATASUM);
Chris Masonbe20aa92007-12-17 20:14:01 -0500162 break;
163 case Opt_nodatacow:
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400164 printk(KERN_INFO "btrfs: setting nodatacow\n");
165 btrfs_set_opt(info->mount_opt, NODATACOW);
166 btrfs_set_opt(info->mount_opt, NODATASUM);
Chris Mason95e05282007-08-29 09:11:44 -0400167 break;
Chris Masonc8b97812008-10-29 14:49:59 -0400168 case Opt_compress:
169 printk(KERN_INFO "btrfs: use compression\n");
170 btrfs_set_opt(info->mount_opt, COMPRESS);
171 break;
Chris Masone18e4802008-01-18 10:54:22 -0500172 case Opt_ssd:
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400173 printk(KERN_INFO "btrfs: use ssd allocation scheme\n");
174 btrfs_set_opt(info->mount_opt, SSD);
Chris Masone18e4802008-01-18 10:54:22 -0500175 break;
Chris Mason21ad10c2008-01-09 09:23:21 -0500176 case Opt_nobarrier:
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400177 printk(KERN_INFO "btrfs: turning off barriers\n");
178 btrfs_set_opt(info->mount_opt, NOBARRIER);
Chris Mason21ad10c2008-01-09 09:23:21 -0500179 break;
Chris Mason4543df72008-06-11 21:47:56 -0400180 case Opt_thread_pool:
181 intarg = 0;
182 match_int(&args[0], &intarg);
183 if (intarg) {
184 info->thread_pool_size = intarg;
185 printk(KERN_INFO "btrfs: thread pool %d\n",
186 info->thread_pool_size);
187 }
188 break;
Chris Masonc59f8952007-12-17 20:14:04 -0500189 case Opt_max_extent:
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400190 num = match_strdup(&args[0]);
191 if (num) {
192 info->max_extent = btrfs_parse_size(num);
193 kfree(num);
Chris Masonc59f8952007-12-17 20:14:04 -0500194
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400195 info->max_extent = max_t(u64,
196 info->max_extent, root->sectorsize);
197 printk(KERN_INFO "btrfs: max_extent at %llu\n",
198 info->max_extent);
Chris Masonc59f8952007-12-17 20:14:04 -0500199 }
200 break;
Chris Mason6f568d32008-01-29 16:03:38 -0500201 case Opt_max_inline:
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400202 num = match_strdup(&args[0]);
203 if (num) {
204 info->max_inline = btrfs_parse_size(num);
205 kfree(num);
Chris Mason6f568d32008-01-29 16:03:38 -0500206
Chris Mason15ada042008-06-11 16:51:38 -0400207 if (info->max_inline) {
208 info->max_inline = max_t(u64,
209 info->max_inline,
210 root->sectorsize);
211 }
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400212 printk(KERN_INFO "btrfs: max_inline at %llu\n",
213 info->max_inline);
Chris Mason6f568d32008-01-29 16:03:38 -0500214 }
215 break;
Chris Mason8f662a72008-01-02 10:01:11 -0500216 case Opt_alloc_start:
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400217 num = match_strdup(&args[0]);
218 if (num) {
219 info->alloc_start = btrfs_parse_size(num);
220 kfree(num);
221 printk(KERN_INFO
222 "btrfs: allocations start at %llu\n",
223 info->alloc_start);
Chris Mason8f662a72008-01-02 10:01:11 -0500224 }
225 break;
Josef Bacik33268ea2008-07-24 12:16:36 -0400226 case Opt_noacl:
227 root->fs_info->sb->s_flags &= ~MS_POSIXACL;
228 break;
Sage Weil3a5e1402009-04-02 16:49:40 -0400229 case Opt_notreelog:
230 printk(KERN_INFO "btrfs: disabling tree log\n");
231 btrfs_set_opt(info->mount_opt, NOTREELOG);
232 break;
Sage Weildccae992009-04-02 16:59:01 -0400233 case Opt_flushoncommit:
234 printk(KERN_INFO "btrfs: turning on flush-on-commit\n");
235 btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT);
236 break;
Chris Mason95e05282007-08-29 09:11:44 -0400237 default:
Chris Masonbe20aa92007-12-17 20:14:01 -0500238 break;
Chris Mason95e05282007-08-29 09:11:44 -0400239 }
240 }
Chris Masonbe20aa92007-12-17 20:14:01 -0500241 kfree(options);
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400242 return 0;
243}
244
245/*
246 * Parse mount options that are required early in the mount process.
247 *
248 * All other options will be parsed on much later in the mount process and
249 * only when we need to allocate a new super block.
250 */
Christoph Hellwig97288f22008-12-02 06:36:09 -0500251static int btrfs_parse_early_options(const char *options, fmode_t flags,
Christoph Hellwig43e570b2008-06-10 10:40:46 -0400252 void *holder, char **subvol_name,
253 struct btrfs_fs_devices **fs_devices)
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400254{
255 substring_t args[MAX_OPT_ARGS];
256 char *opts, *p;
257 int error = 0;
258
259 if (!options)
260 goto out;
261
262 /*
263 * strsep changes the string, duplicate it because parse_options
264 * gets called twice
265 */
266 opts = kstrdup(options, GFP_KERNEL);
267 if (!opts)
268 return -ENOMEM;
269
270 while ((p = strsep(&opts, ",")) != NULL) {
271 int token;
272 if (!*p)
273 continue;
274
275 token = match_token(p, tokens, args);
276 switch (token) {
277 case Opt_subvol:
278 *subvol_name = match_strdup(&args[0]);
279 break;
Christoph Hellwig43e570b2008-06-10 10:40:46 -0400280 case Opt_device:
281 error = btrfs_scan_one_device(match_strdup(&args[0]),
282 flags, holder, fs_devices);
283 if (error)
284 goto out_free_opts;
285 break;
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400286 default:
287 break;
288 }
289 }
290
Christoph Hellwig43e570b2008-06-10 10:40:46 -0400291 out_free_opts:
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400292 kfree(opts);
293 out:
294 /*
295 * If no subvolume name is specified we use the default one. Allocate
Chris Mason3de45862008-11-17 21:02:50 -0500296 * a copy of the string "." here so that code later in the
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400297 * mount path doesn't care if it's the default volume or another one.
298 */
299 if (!*subvol_name) {
Chris Mason3de45862008-11-17 21:02:50 -0500300 *subvol_name = kstrdup(".", GFP_KERNEL);
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400301 if (!*subvol_name)
302 return -ENOMEM;
303 }
304 return error;
Chris Mason95e05282007-08-29 09:11:44 -0400305}
306
Chris Masond3977122009-01-05 21:25:51 -0500307static int btrfs_fill_super(struct super_block *sb,
Chris Mason8a4b83c2008-03-24 15:02:07 -0400308 struct btrfs_fs_devices *fs_devices,
Chris Masond3977122009-01-05 21:25:51 -0500309 void *data, int silent)
Chris Mason2e635a22007-03-21 11:12:56 -0400310{
Chris Masond3977122009-01-05 21:25:51 -0500311 struct inode *inode;
312 struct dentry *root_dentry;
Chris Masone20d96d2007-03-22 12:13:20 -0400313 struct btrfs_super_block *disk_super;
Chris Mason0f7d52f2007-04-09 10:42:37 -0400314 struct btrfs_root *tree_root;
Chris Masond6e4a422007-04-06 15:37:36 -0400315 struct btrfs_inode *bi;
Chris Mason39279cc2007-06-12 06:35:45 -0400316 int err;
Chris Mason2e635a22007-03-21 11:12:56 -0400317
318 sb->s_maxbytes = MAX_LFS_FILESIZE;
Chris Mason2e635a22007-03-21 11:12:56 -0400319 sb->s_magic = BTRFS_SUPER_MAGIC;
Chris Masone20d96d2007-03-22 12:13:20 -0400320 sb->s_op = &btrfs_super_ops;
Balaji Raobe6e8dc2008-07-21 02:01:56 +0530321 sb->s_export_op = &btrfs_export_ops;
Josef Bacik5103e942007-11-16 11:45:54 -0500322 sb->s_xattr = btrfs_xattr_handlers;
Chris Mason2e635a22007-03-21 11:12:56 -0400323 sb->s_time_gran = 1;
Josef Bacik33268ea2008-07-24 12:16:36 -0400324 sb->s_flags |= MS_POSIXACL;
Chris Masone20d96d2007-03-22 12:13:20 -0400325
Chris Masondfe25022008-05-13 13:46:40 -0400326 tree_root = open_ctree(sb, fs_devices, (char *)data);
Chris Masond98237b2007-03-28 13:57:48 -0400327
Yane58ca022008-04-01 11:21:34 -0400328 if (IS_ERR(tree_root)) {
Chris Masone20d96d2007-03-22 12:13:20 -0400329 printk("btrfs: open_ctree failed\n");
Yane58ca022008-04-01 11:21:34 -0400330 return PTR_ERR(tree_root);
Chris Masone20d96d2007-03-22 12:13:20 -0400331 }
Chris Mason0f7d52f2007-04-09 10:42:37 -0400332 sb->s_fs_info = tree_root;
Chris Mason5f39d392007-10-15 16:14:19 -0400333 disk_super = &tree_root->fs_info->super_copy;
Chris Mason3de45862008-11-17 21:02:50 -0500334 inode = btrfs_iget_locked(sb, BTRFS_FIRST_FREE_OBJECTID,
335 tree_root->fs_info->fs_root);
Chris Masond6e4a422007-04-06 15:37:36 -0400336 bi = BTRFS_I(inode);
337 bi->location.objectid = inode->i_ino;
338 bi->location.offset = 0;
Chris Mason3de45862008-11-17 21:02:50 -0500339 bi->root = tree_root->fs_info->fs_root;
Chris Masonb888db22007-08-27 16:49:44 -0400340
Chris Masond6e4a422007-04-06 15:37:36 -0400341 btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY);
342
Chris Mason39279cc2007-06-12 06:35:45 -0400343 if (!inode) {
344 err = -ENOMEM;
345 goto fail_close;
346 }
Chris Masone20d96d2007-03-22 12:13:20 -0400347 if (inode->i_state & I_NEW) {
348 btrfs_read_locked_inode(inode);
349 unlock_new_inode(inode);
350 }
Chris Mason2e635a22007-03-21 11:12:56 -0400351
Chris Masone20d96d2007-03-22 12:13:20 -0400352 root_dentry = d_alloc_root(inode);
353 if (!root_dentry) {
Chris Mason2e635a22007-03-21 11:12:56 -0400354 iput(inode);
Chris Mason39279cc2007-06-12 06:35:45 -0400355 err = -ENOMEM;
356 goto fail_close;
Chris Mason2e635a22007-03-21 11:12:56 -0400357 }
Yan Zhenge4404d62008-12-12 10:03:26 -0500358#if 0
Josef Bacik58176a92007-08-29 15:47:34 -0400359 /* this does the super kobj at the same time */
360 err = btrfs_sysfs_add_super(tree_root->fs_info);
361 if (err)
362 goto fail_close;
Yan Zhenge4404d62008-12-12 10:03:26 -0500363#endif
Josef Bacik58176a92007-08-29 15:47:34 -0400364
Chris Masone20d96d2007-03-22 12:13:20 -0400365 sb->s_root = root_dentry;
Chris Mason6885f302008-02-20 16:11:05 -0500366
Chris Mason6885f302008-02-20 16:11:05 -0500367 save_mount_options(sb, data);
Chris Mason2e635a22007-03-21 11:12:56 -0400368 return 0;
Chris Mason2e635a22007-03-21 11:12:56 -0400369
Chris Mason39279cc2007-06-12 06:35:45 -0400370fail_close:
371 close_ctree(tree_root);
Chris Masond5719762007-03-23 10:01:08 -0400372 return err;
373}
374
Sage Weil6bf13c02008-06-10 10:07:39 -0400375int btrfs_sync_fs(struct super_block *sb, int wait)
Chris Masond5719762007-03-23 10:01:08 -0400376{
377 struct btrfs_trans_handle *trans;
Sage Weildccae992009-04-02 16:59:01 -0400378 struct btrfs_root *root = btrfs_sb(sb);
Chris Masond5719762007-03-23 10:01:08 -0400379 int ret;
Chris Masondf2ce342007-03-23 11:00:45 -0400380
Yan Zhengc146afa2008-11-12 14:34:12 -0500381 if (sb->s_flags & MS_RDONLY)
382 return 0;
383
Chris Masond5719762007-03-23 10:01:08 -0400384 sb->s_dirt = 0;
Chris Masond561c022007-03-23 19:47:49 -0400385 if (!wait) {
Chris Mason7cfcc172007-04-02 14:53:59 -0400386 filemap_flush(root->fs_info->btree_inode->i_mapping);
Chris Masond561c022007-03-23 19:47:49 -0400387 return 0;
388 }
Chris Mason771ed682008-11-06 22:02:51 -0500389
390 btrfs_start_delalloc_inodes(root);
391 btrfs_wait_ordered_extents(root, 0);
392
Chris Masond5719762007-03-23 10:01:08 -0400393 trans = btrfs_start_transaction(root, 1);
394 ret = btrfs_commit_transaction(trans, root);
395 sb->s_dirt = 0;
Chris Mason54aa1f42007-06-22 14:16:25 -0400396 return ret;
Chris Masond5719762007-03-23 10:01:08 -0400397}
398
Eric Parisa9572a12009-04-02 16:46:06 -0400399static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
400{
401 struct btrfs_root *root = btrfs_sb(vfs->mnt_sb);
402 struct btrfs_fs_info *info = root->fs_info;
403
404 if (btrfs_test_opt(root, DEGRADED))
405 seq_puts(seq, ",degraded");
406 if (btrfs_test_opt(root, NODATASUM))
407 seq_puts(seq, ",nodatasum");
408 if (btrfs_test_opt(root, NODATACOW))
409 seq_puts(seq, ",nodatacow");
410 if (btrfs_test_opt(root, NOBARRIER))
411 seq_puts(seq, ",nobarrier");
412 if (info->max_extent != (u64)-1)
413 seq_printf(seq, ",max_extent=%llu", info->max_extent);
414 if (info->max_inline != 8192 * 1024)
415 seq_printf(seq, ",max_inline=%llu", info->max_inline);
416 if (info->alloc_start != 0)
417 seq_printf(seq, ",alloc_start=%llu", info->alloc_start);
418 if (info->thread_pool_size != min_t(unsigned long,
419 num_online_cpus() + 2, 8))
420 seq_printf(seq, ",thread_pool=%d", info->thread_pool_size);
421 if (btrfs_test_opt(root, COMPRESS))
422 seq_puts(seq, ",compress");
423 if (btrfs_test_opt(root, SSD))
424 seq_puts(seq, ",ssd");
Sage Weil3a5e1402009-04-02 16:49:40 -0400425 if (btrfs_test_opt(root, NOTREELOG))
Sage Weildccae992009-04-02 16:59:01 -0400426 seq_puts(seq, ",no-treelog");
427 if (btrfs_test_opt(root, FLUSHONCOMMIT))
428 seq_puts(seq, ",flush-on-commit");
Eric Parisa9572a12009-04-02 16:46:06 -0400429 if (!(root->fs_info->sb->s_flags & MS_POSIXACL))
430 seq_puts(seq, ",noacl");
431 return 0;
432}
433
Chris Masond561c022007-03-23 19:47:49 -0400434static void btrfs_write_super(struct super_block *sb)
435{
Chris Mason08607c12007-06-08 15:33:54 -0400436 sb->s_dirt = 0;
Chris Masond561c022007-03-23 19:47:49 -0400437}
438
Chris Masona061fc82008-05-07 11:43:44 -0400439static int btrfs_test_super(struct super_block *s, void *data)
Chris Mason2e635a22007-03-21 11:12:56 -0400440{
Chris Masona061fc82008-05-07 11:43:44 -0400441 struct btrfs_fs_devices *test_fs_devices = data;
442 struct btrfs_root *root = btrfs_sb(s);
Yan4b82d6e2007-08-29 09:11:44 -0400443
Chris Masona061fc82008-05-07 11:43:44 -0400444 return root->fs_info->fs_devices == test_fs_devices;
Yan4b82d6e2007-08-29 09:11:44 -0400445}
446
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400447/*
448 * Find a superblock for the given device / mount point.
449 *
450 * Note: This is based on get_sb_bdev from fs/super.c with a few additions
451 * for multiple device setup. Make sure to keep it in sync.
452 */
453static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
454 const char *dev_name, void *data, struct vfsmount *mnt)
Yan4b82d6e2007-08-29 09:11:44 -0400455{
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400456 char *subvol_name = NULL;
Yan4b82d6e2007-08-29 09:11:44 -0400457 struct block_device *bdev = NULL;
458 struct super_block *s;
459 struct dentry *root;
Chris Mason8a4b83c2008-03-24 15:02:07 -0400460 struct btrfs_fs_devices *fs_devices = NULL;
Christoph Hellwig97288f22008-12-02 06:36:09 -0500461 fmode_t mode = FMODE_READ;
Yan4b82d6e2007-08-29 09:11:44 -0400462 int error = 0;
463
Christoph Hellwig97288f22008-12-02 06:36:09 -0500464 if (!(flags & MS_RDONLY))
465 mode |= FMODE_WRITE;
466
467 error = btrfs_parse_early_options(data, mode, fs_type,
Christoph Hellwig43e570b2008-06-10 10:40:46 -0400468 &subvol_name, &fs_devices);
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400469 if (error)
Shen Feng1f483662009-01-05 15:43:42 -0500470 return error;
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400471
Christoph Hellwig97288f22008-12-02 06:36:09 -0500472 error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices);
Chris Mason8a4b83c2008-03-24 15:02:07 -0400473 if (error)
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400474 goto error_free_subvol_name;
Yan4b82d6e2007-08-29 09:11:44 -0400475
Christoph Hellwig97288f22008-12-02 06:36:09 -0500476 error = btrfs_open_devices(fs_devices, mode, fs_type);
Chris Mason8a4b83c2008-03-24 15:02:07 -0400477 if (error)
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400478 goto error_free_subvol_name;
Chris Mason8a4b83c2008-03-24 15:02:07 -0400479
Yan Zheng2b820322008-11-17 21:11:30 -0500480 if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) {
481 error = -EACCES;
482 goto error_close_devices;
483 }
484
Chris Masondfe25022008-05-13 13:46:40 -0400485 bdev = fs_devices->latest_bdev;
Chris Masona061fc82008-05-07 11:43:44 -0400486 s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices);
Yan4b82d6e2007-08-29 09:11:44 -0400487 if (IS_ERR(s))
488 goto error_s;
489
490 if (s->s_root) {
491 if ((flags ^ s->s_flags) & MS_RDONLY) {
492 up_write(&s->s_umount);
493 deactivate_super(s);
494 error = -EBUSY;
Yan Zhengc146afa2008-11-12 14:34:12 -0500495 goto error_close_devices;
Yan4b82d6e2007-08-29 09:11:44 -0400496 }
497
Yan Zheng2b820322008-11-17 21:11:30 -0500498 btrfs_close_devices(fs_devices);
Yan4b82d6e2007-08-29 09:11:44 -0400499 } else {
500 char b[BDEVNAME_SIZE];
501
502 s->s_flags = flags;
503 strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id));
Chris Mason8a4b83c2008-03-24 15:02:07 -0400504 error = btrfs_fill_super(s, fs_devices, data,
505 flags & MS_SILENT ? 1 : 0);
Yan4b82d6e2007-08-29 09:11:44 -0400506 if (error) {
507 up_write(&s->s_umount);
508 deactivate_super(s);
Shen Feng1f483662009-01-05 15:43:42 -0500509 goto error_free_subvol_name;
Yan4b82d6e2007-08-29 09:11:44 -0400510 }
511
Chris Mason788f20e2008-04-28 15:29:42 -0400512 btrfs_sb(s)->fs_info->bdev_holder = fs_type;
Yan4b82d6e2007-08-29 09:11:44 -0400513 s->s_flags |= MS_ACTIVE;
514 }
515
David Woodhouse76fcef12008-08-19 16:49:35 +0100516 if (!strcmp(subvol_name, "."))
517 root = dget(s->s_root);
518 else {
519 mutex_lock(&s->s_root->d_inode->i_mutex);
Chris Masond3977122009-01-05 21:25:51 -0500520 root = lookup_one_len(subvol_name, s->s_root,
521 strlen(subvol_name));
David Woodhouse76fcef12008-08-19 16:49:35 +0100522 mutex_unlock(&s->s_root->d_inode->i_mutex);
Chris Masond3977122009-01-05 21:25:51 -0500523
David Woodhouse76fcef12008-08-19 16:49:35 +0100524 if (IS_ERR(root)) {
525 up_write(&s->s_umount);
526 deactivate_super(s);
527 error = PTR_ERR(root);
Shen Feng1f483662009-01-05 15:43:42 -0500528 goto error_free_subvol_name;
David Woodhouse76fcef12008-08-19 16:49:35 +0100529 }
530 if (!root->d_inode) {
531 dput(root);
532 up_write(&s->s_umount);
533 deactivate_super(s);
534 error = -ENXIO;
Shen Feng1f483662009-01-05 15:43:42 -0500535 goto error_free_subvol_name;
David Woodhouse76fcef12008-08-19 16:49:35 +0100536 }
Yan4b82d6e2007-08-29 09:11:44 -0400537 }
538
539 mnt->mnt_sb = s;
540 mnt->mnt_root = root;
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400541
542 kfree(subvol_name);
Yan4b82d6e2007-08-29 09:11:44 -0400543 return 0;
544
545error_s:
546 error = PTR_ERR(s);
Yan Zhengc146afa2008-11-12 14:34:12 -0500547error_close_devices:
Chris Mason8a4b83c2008-03-24 15:02:07 -0400548 btrfs_close_devices(fs_devices);
Christoph Hellwigedf24ab2008-06-10 10:40:29 -0400549error_free_subvol_name:
550 kfree(subvol_name);
Yan4b82d6e2007-08-29 09:11:44 -0400551 return error;
552}
Chris Mason2e635a22007-03-21 11:12:56 -0400553
Yan Zhengc146afa2008-11-12 14:34:12 -0500554static int btrfs_remount(struct super_block *sb, int *flags, char *data)
555{
556 struct btrfs_root *root = btrfs_sb(sb);
557 int ret;
558
Chris Masonb2880522009-02-12 09:37:35 -0500559 ret = btrfs_parse_options(root, data);
560 if (ret)
561 return -EINVAL;
562
Yan Zhengc146afa2008-11-12 14:34:12 -0500563 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
564 return 0;
565
566 if (*flags & MS_RDONLY) {
567 sb->s_flags |= MS_RDONLY;
568
569 ret = btrfs_commit_super(root);
570 WARN_ON(ret);
571 } else {
Yan Zheng2b820322008-11-17 21:11:30 -0500572 if (root->fs_info->fs_devices->rw_devices == 0)
573 return -EACCES;
574
Yan Zhengc146afa2008-11-12 14:34:12 -0500575 if (btrfs_super_log_root(&root->fs_info->super_copy) != 0)
576 return -EINVAL;
577
578 ret = btrfs_cleanup_reloc_trees(root);
579 WARN_ON(ret);
580
581 ret = btrfs_cleanup_fs_roots(root->fs_info);
582 WARN_ON(ret);
583
584 sb->s_flags &= ~MS_RDONLY;
585 }
586
587 return 0;
588}
589
Chris Mason8fd17792007-04-19 21:01:03 -0400590static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
591{
592 struct btrfs_root *root = btrfs_sb(dentry->d_sb);
Chris Mason4b52dff2007-06-26 10:06:50 -0400593 struct btrfs_super_block *disk_super = &root->fs_info->super_copy;
Chris Masondb945352007-10-15 16:15:53 -0400594 int bits = dentry->d_sb->s_blocksize_bits;
David Woodhouse9d036322008-08-18 12:01:52 +0100595 __be32 *fsid = (__be32 *)root->fs_info->fsid;
Chris Mason8fd17792007-04-19 21:01:03 -0400596
597 buf->f_namelen = BTRFS_NAME_LEN;
Chris Masondb945352007-10-15 16:15:53 -0400598 buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits;
599 buf->f_bfree = buf->f_blocks -
600 (btrfs_super_bytes_used(disk_super) >> bits);
Chris Mason8fd17792007-04-19 21:01:03 -0400601 buf->f_bavail = buf->f_bfree;
602 buf->f_bsize = dentry->d_sb->s_blocksize;
603 buf->f_type = BTRFS_SUPER_MAGIC;
Chris Masond3977122009-01-05 21:25:51 -0500604
David Woodhouse9d036322008-08-18 12:01:52 +0100605 /* We treat it as constant endianness (it doesn't matter _which_)
Chris Masond3977122009-01-05 21:25:51 -0500606 because we want the fsid to come out the same whether mounted
David Woodhouse9d036322008-08-18 12:01:52 +0100607 on a big-endian or little-endian host */
608 buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]);
609 buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]);
David Woodhouse32d48fa2008-08-18 13:10:20 +0100610 /* Mask in the root object ID too, to disambiguate subvols */
611 buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32;
612 buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid;
613
Chris Mason8fd17792007-04-19 21:01:03 -0400614 return 0;
615}
Chris Masonb5133862007-04-24 11:52:22 -0400616
Chris Mason2e635a22007-03-21 11:12:56 -0400617static struct file_system_type btrfs_fs_type = {
618 .owner = THIS_MODULE,
619 .name = "btrfs",
620 .get_sb = btrfs_get_sb,
Chris Masona061fc82008-05-07 11:43:44 -0400621 .kill_sb = kill_anon_super,
Chris Mason2e635a22007-03-21 11:12:56 -0400622 .fs_flags = FS_REQUIRES_DEV,
623};
Chris Masona9218f62008-03-24 15:02:04 -0400624
Chris Masond352ac62008-09-29 15:18:18 -0400625/*
626 * used by btrfsctl to scan devices when no FS is mounted
627 */
Chris Mason8a4b83c2008-03-24 15:02:07 -0400628static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
629 unsigned long arg)
630{
631 struct btrfs_ioctl_vol_args *vol;
632 struct btrfs_fs_devices *fs_devices;
Chris Masonc071fcf2009-01-16 11:59:08 -0500633 int ret = -ENOTTY;
Chris Mason8a4b83c2008-03-24 15:02:07 -0400634
Chris Masone441d542009-01-05 16:57:23 -0500635 if (!capable(CAP_SYS_ADMIN))
636 return -EPERM;
637
Li Zefandae7b662009-04-08 15:06:54 +0800638 vol = memdup_user((void __user *)arg, sizeof(*vol));
639 if (IS_ERR(vol))
640 return PTR_ERR(vol);
Chris Masonc071fcf2009-01-16 11:59:08 -0500641
Chris Mason8a4b83c2008-03-24 15:02:07 -0400642 switch (cmd) {
643 case BTRFS_IOC_SCAN_DEV:
Christoph Hellwig97288f22008-12-02 06:36:09 -0500644 ret = btrfs_scan_one_device(vol->name, FMODE_READ,
Chris Mason8a4b83c2008-03-24 15:02:07 -0400645 &btrfs_fs_type, &fs_devices);
646 break;
647 }
Li Zefandae7b662009-04-08 15:06:54 +0800648
Chris Mason8a4b83c2008-03-24 15:02:07 -0400649 kfree(vol);
Linda Knippersf819d832008-06-09 22:17:11 -0400650 return ret;
Chris Mason8a4b83c2008-03-24 15:02:07 -0400651}
652
Linus Torvalds01762602009-01-10 06:09:52 -0800653static int btrfs_freeze(struct super_block *sb)
Yaned0dab62008-01-22 12:46:56 -0500654{
655 struct btrfs_root *root = btrfs_sb(sb);
Chris Masona74a4b92008-06-25 16:01:31 -0400656 mutex_lock(&root->fs_info->transaction_kthread_mutex);
657 mutex_lock(&root->fs_info->cleaner_mutex);
Linus Torvalds01762602009-01-10 06:09:52 -0800658 return 0;
Yaned0dab62008-01-22 12:46:56 -0500659}
660
Linus Torvalds01762602009-01-10 06:09:52 -0800661static int btrfs_unfreeze(struct super_block *sb)
Yaned0dab62008-01-22 12:46:56 -0500662{
663 struct btrfs_root *root = btrfs_sb(sb);
Chris Masona74a4b92008-06-25 16:01:31 -0400664 mutex_unlock(&root->fs_info->cleaner_mutex);
665 mutex_unlock(&root->fs_info->transaction_kthread_mutex);
Linus Torvalds01762602009-01-10 06:09:52 -0800666 return 0;
Yaned0dab62008-01-22 12:46:56 -0500667}
Chris Mason2e635a22007-03-21 11:12:56 -0400668
Chris Masone20d96d2007-03-22 12:13:20 -0400669static struct super_operations btrfs_super_ops = {
Chris Mason134e9732007-03-25 13:44:56 -0400670 .delete_inode = btrfs_delete_inode,
Chris Masone20d96d2007-03-22 12:13:20 -0400671 .put_super = btrfs_put_super,
Chris Masond5719762007-03-23 10:01:08 -0400672 .write_super = btrfs_write_super,
673 .sync_fs = btrfs_sync_fs,
Eric Parisa9572a12009-04-02 16:46:06 -0400674 .show_options = btrfs_show_options,
Chris Mason4730a4b2007-03-26 12:00:39 -0400675 .write_inode = btrfs_write_inode,
Chris Masonb5133862007-04-24 11:52:22 -0400676 .dirty_inode = btrfs_dirty_inode,
Chris Mason2c90e5d2007-04-02 10:50:19 -0400677 .alloc_inode = btrfs_alloc_inode,
678 .destroy_inode = btrfs_destroy_inode,
Chris Mason8fd17792007-04-19 21:01:03 -0400679 .statfs = btrfs_statfs,
Yan Zhengc146afa2008-11-12 14:34:12 -0500680 .remount_fs = btrfs_remount,
Linus Torvalds01762602009-01-10 06:09:52 -0800681 .freeze_fs = btrfs_freeze,
682 .unfreeze_fs = btrfs_unfreeze,
Chris Masone20d96d2007-03-22 12:13:20 -0400683};
Chris Masona9218f62008-03-24 15:02:04 -0400684
685static const struct file_operations btrfs_ctl_fops = {
686 .unlocked_ioctl = btrfs_control_ioctl,
687 .compat_ioctl = btrfs_control_ioctl,
688 .owner = THIS_MODULE,
689};
690
691static struct miscdevice btrfs_misc = {
692 .minor = MISC_DYNAMIC_MINOR,
693 .name = "btrfs-control",
694 .fops = &btrfs_ctl_fops
695};
696
697static int btrfs_interface_init(void)
698{
699 return misc_register(&btrfs_misc);
700}
701
Christoph Hellwigb2950862008-12-02 09:54:17 -0500702static void btrfs_interface_exit(void)
Chris Masona9218f62008-03-24 15:02:04 -0400703{
704 if (misc_deregister(&btrfs_misc) < 0)
Chris Masond3977122009-01-05 21:25:51 -0500705 printk(KERN_INFO "misc_deregister failed for control device");
Chris Masona9218f62008-03-24 15:02:04 -0400706}
707
Chris Mason2e635a22007-03-21 11:12:56 -0400708static int __init init_btrfs_fs(void)
709{
Chris Mason2c90e5d2007-04-02 10:50:19 -0400710 int err;
Josef Bacik58176a92007-08-29 15:47:34 -0400711
712 err = btrfs_init_sysfs();
713 if (err)
714 return err;
715
Chris Mason39279cc2007-06-12 06:35:45 -0400716 err = btrfs_init_cachep();
Chris Mason2c90e5d2007-04-02 10:50:19 -0400717 if (err)
Chris Masona74a4b92008-06-25 16:01:31 -0400718 goto free_sysfs;
Chris Masond1310b22008-01-24 16:13:08 -0500719
720 err = extent_io_init();
Wyatt Banks2f4cbe62007-11-19 10:22:33 -0500721 if (err)
722 goto free_cachep;
723
Chris Masond1310b22008-01-24 16:13:08 -0500724 err = extent_map_init();
725 if (err)
726 goto free_extent_io;
727
Chris Masona9218f62008-03-24 15:02:04 -0400728 err = btrfs_interface_init();
Wyatt Banks2f4cbe62007-11-19 10:22:33 -0500729 if (err)
730 goto free_extent_map;
Chris Masonc8b97812008-10-29 14:49:59 -0400731
Chris Masona9218f62008-03-24 15:02:04 -0400732 err = register_filesystem(&btrfs_fs_type);
733 if (err)
734 goto unregister_ioctl;
Chris Masonb3c3da72008-07-23 12:12:13 -0400735
736 printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION);
Wyatt Banks2f4cbe62007-11-19 10:22:33 -0500737 return 0;
738
Chris Masona9218f62008-03-24 15:02:04 -0400739unregister_ioctl:
740 btrfs_interface_exit();
Wyatt Banks2f4cbe62007-11-19 10:22:33 -0500741free_extent_map:
742 extent_map_exit();
Chris Masond1310b22008-01-24 16:13:08 -0500743free_extent_io:
744 extent_io_exit();
Wyatt Banks2f4cbe62007-11-19 10:22:33 -0500745free_cachep:
746 btrfs_destroy_cachep();
Chris Masona74a4b92008-06-25 16:01:31 -0400747free_sysfs:
Wyatt Banks2f4cbe62007-11-19 10:22:33 -0500748 btrfs_exit_sysfs();
749 return err;
Chris Mason2e635a22007-03-21 11:12:56 -0400750}
751
752static void __exit exit_btrfs_fs(void)
753{
Chris Mason39279cc2007-06-12 06:35:45 -0400754 btrfs_destroy_cachep();
Chris Masona52d9a82007-08-27 16:49:44 -0400755 extent_map_exit();
Chris Masond1310b22008-01-24 16:13:08 -0500756 extent_io_exit();
Chris Masona9218f62008-03-24 15:02:04 -0400757 btrfs_interface_exit();
Chris Mason2e635a22007-03-21 11:12:56 -0400758 unregister_filesystem(&btrfs_fs_type);
Josef Bacik58176a92007-08-29 15:47:34 -0400759 btrfs_exit_sysfs();
Chris Mason8a4b83c2008-03-24 15:02:07 -0400760 btrfs_cleanup_fs_uuids();
Chris Masonc8b97812008-10-29 14:49:59 -0400761 btrfs_zlib_exit();
Chris Mason2e635a22007-03-21 11:12:56 -0400762}
763
764module_init(init_btrfs_fs)
765module_exit(exit_btrfs_fs)
766
767MODULE_LICENSE("GPL");