2 * Copyright (C) 2007 Oracle. All rights reserved.
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.
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.
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.
19 #include <linux/blkdev.h>
20 #include <linux/module.h>
21 #include <linux/buffer_head.h>
23 #include <linux/pagemap.h>
24 #include <linux/highmem.h>
25 #include <linux/time.h>
26 #include <linux/init.h>
27 #include <linux/string.h>
28 #include <linux/smp_lock.h>
29 #include <linux/backing-dev.h>
30 #include <linux/mount.h>
31 #include <linux/mpage.h>
32 #include <linux/swap.h>
33 #include <linux/writeback.h>
34 #include <linux/statfs.h>
35 #include <linux/compat.h>
36 #include <linux/parser.h>
37 #include <linux/ctype.h>
38 #include <linux/namei.h>
39 #include <linux/miscdevice.h>
42 #include "transaction.h"
43 #include "btrfs_inode.h"
45 #include "print-tree.h"
49 #define BTRFS_SUPER_MAGIC 0x9123683E
51 static struct super_operations btrfs_super_ops;
53 static void btrfs_put_super (struct super_block * sb)
55 struct btrfs_root *root = btrfs_sb(sb);
56 struct btrfs_fs_info *fs = root->fs_info;
59 ret = close_ctree(root);
61 printk("close ctree returns %d\n", ret);
63 btrfs_sysfs_del_super(fs);
68 Opt_degraded, Opt_subvol, Opt_nodatasum, Opt_nodatacow,
69 Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier,
73 static match_table_t tokens = {
74 {Opt_degraded, "degraded"},
75 {Opt_subvol, "subvol=%s"},
76 {Opt_nodatasum, "nodatasum"},
77 {Opt_nodatacow, "nodatacow"},
78 {Opt_nobarrier, "nobarrier"},
79 {Opt_max_extent, "max_extent=%s"},
80 {Opt_max_inline, "max_inline=%s"},
81 {Opt_alloc_start, "alloc_start=%s"},
86 u64 btrfs_parse_size(char *str)
93 res = simple_strtoul(str, &end, 10);
111 int btrfs_parse_options(char *options, struct btrfs_root *root,
115 struct btrfs_fs_info *info = NULL;
116 substring_t args[MAX_OPT_ARGS];
122 * strsep changes the string, duplicate it because parse_options
125 options = kstrdup(options, GFP_NOFS);
130 info = root->fs_info;
132 while ((p = strsep (&options, ",")) != NULL) {
137 token = match_token(p, tokens, args);
141 printk("btrfs: allowing degraded mounts\n");
142 btrfs_set_opt(info->mount_opt, DEGRADED);
147 *subvol_name = match_strdup(&args[0]);
152 printk("btrfs: setting nodatacsum\n");
153 btrfs_set_opt(info->mount_opt, NODATASUM);
158 printk("btrfs: setting nodatacow\n");
159 btrfs_set_opt(info->mount_opt, NODATACOW);
160 btrfs_set_opt(info->mount_opt, NODATASUM);
165 printk("btrfs: use ssd allocation scheme\n");
166 btrfs_set_opt(info->mount_opt, SSD);
171 printk("btrfs: turning off barriers\n");
172 btrfs_set_opt(info->mount_opt, NOBARRIER);
177 char *num = match_strdup(&args[0]);
180 btrfs_parse_size(num);
183 info->max_extent = max_t(u64,
186 printk("btrfs: max_extent at %Lu\n",
193 char *num = match_strdup(&args[0]);
196 btrfs_parse_size(num);
199 info->max_inline = max_t(u64,
202 printk("btrfs: max_inline at %Lu\n",
207 case Opt_alloc_start:
209 char *num = match_strdup(&args[0]);
212 btrfs_parse_size(num);
214 printk("btrfs: allocations start at "
215 "%Lu\n", info->alloc_start);
227 static int btrfs_fill_super(struct super_block * sb,
228 struct btrfs_fs_devices *fs_devices,
229 void * data, int silent)
231 struct inode * inode;
232 struct dentry * root_dentry;
233 struct btrfs_super_block *disk_super;
234 struct btrfs_root *tree_root;
235 struct btrfs_inode *bi;
238 sb->s_maxbytes = MAX_LFS_FILESIZE;
239 sb->s_magic = BTRFS_SUPER_MAGIC;
240 sb->s_op = &btrfs_super_ops;
241 sb->s_xattr = btrfs_xattr_handlers;
244 tree_root = open_ctree(sb, fs_devices, (char *)data);
246 if (IS_ERR(tree_root)) {
247 printk("btrfs: open_ctree failed\n");
248 return PTR_ERR(tree_root);
250 sb->s_fs_info = tree_root;
251 disk_super = &tree_root->fs_info->super_copy;
252 inode = btrfs_iget_locked(sb, btrfs_super_root_dir(disk_super),
255 bi->location.objectid = inode->i_ino;
256 bi->location.offset = 0;
257 bi->root = tree_root;
259 btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY);
265 if (inode->i_state & I_NEW) {
266 btrfs_read_locked_inode(inode);
267 unlock_new_inode(inode);
270 root_dentry = d_alloc_root(inode);
277 /* this does the super kobj at the same time */
278 err = btrfs_sysfs_add_super(tree_root->fs_info);
282 sb->s_root = root_dentry;
283 btrfs_transaction_queue_work(tree_root, HZ * 30);
285 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,25)
286 save_mount_options(sb, data);
292 close_ctree(tree_root);
296 static int btrfs_sync_fs(struct super_block *sb, int wait)
298 struct btrfs_trans_handle *trans;
299 struct btrfs_root *root;
305 filemap_flush(root->fs_info->btree_inode->i_mapping);
308 btrfs_clean_old_snapshots(root);
309 mutex_lock(&root->fs_info->fs_mutex);
310 btrfs_defrag_dirty_roots(root->fs_info);
311 trans = btrfs_start_transaction(root, 1);
312 ret = btrfs_commit_transaction(trans, root);
314 mutex_unlock(&root->fs_info->fs_mutex);
318 static void btrfs_write_super(struct super_block *sb)
323 static int btrfs_test_super(struct super_block *s, void *data)
325 struct btrfs_fs_devices *test_fs_devices = data;
326 struct btrfs_root *root = btrfs_sb(s);
328 return root->fs_info->fs_devices == test_fs_devices;
331 int btrfs_get_sb_bdev(struct file_system_type *fs_type,
332 int flags, const char *dev_name, void *data,
333 struct vfsmount *mnt, const char *subvol)
335 struct block_device *bdev = NULL;
336 struct super_block *s;
338 struct btrfs_fs_devices *fs_devices = NULL;
341 error = btrfs_scan_one_device(dev_name, flags, fs_type, &fs_devices);
345 error = btrfs_open_devices(fs_devices, flags, fs_type);
349 bdev = fs_devices->latest_bdev;
350 btrfs_lock_volumes();
351 s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices);
352 btrfs_unlock_volumes();
357 if ((flags ^ s->s_flags) & MS_RDONLY) {
358 up_write(&s->s_umount);
365 char b[BDEVNAME_SIZE];
368 strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id));
369 error = btrfs_fill_super(s, fs_devices, data,
370 flags & MS_SILENT ? 1 : 0);
372 up_write(&s->s_umount);
377 btrfs_sb(s)->fs_info->bdev_holder = fs_type;
378 s->s_flags |= MS_ACTIVE;
382 root = lookup_one_len(subvol, s->s_root, strlen(subvol));
384 up_write(&s->s_umount);
386 error = PTR_ERR(root);
389 if (!root->d_inode) {
391 up_write(&s->s_umount);
397 root = dget(s->s_root);
401 mnt->mnt_root = root;
407 btrfs_close_devices(fs_devices);
411 /* end copy & paste */
413 static int btrfs_get_sb(struct file_system_type *fs_type,
414 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
417 char *subvol_name = NULL;
419 btrfs_parse_options((char *)data, NULL, &subvol_name);
420 ret = btrfs_get_sb_bdev(fs_type, flags, dev_name, data, mnt,
421 subvol_name ? subvol_name : "default");
427 static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
429 struct btrfs_root *root = btrfs_sb(dentry->d_sb);
430 struct btrfs_super_block *disk_super = &root->fs_info->super_copy;
431 int bits = dentry->d_sb->s_blocksize_bits;
433 buf->f_namelen = BTRFS_NAME_LEN;
434 buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits;
435 buf->f_bfree = buf->f_blocks -
436 (btrfs_super_bytes_used(disk_super) >> bits);
437 buf->f_bavail = buf->f_bfree;
438 buf->f_bsize = dentry->d_sb->s_blocksize;
439 buf->f_type = BTRFS_SUPER_MAGIC;
443 static struct file_system_type btrfs_fs_type = {
444 .owner = THIS_MODULE,
446 .get_sb = btrfs_get_sb,
447 .kill_sb = kill_anon_super,
448 .fs_flags = FS_REQUIRES_DEV,
451 static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
454 struct btrfs_ioctl_vol_args *vol;
455 struct btrfs_fs_devices *fs_devices;
459 vol = kmalloc(sizeof(*vol), GFP_KERNEL);
460 if (copy_from_user(vol, (void __user *)arg, sizeof(*vol))) {
464 len = strnlen(vol->name, BTRFS_PATH_NAME_MAX);
466 case BTRFS_IOC_SCAN_DEV:
467 ret = btrfs_scan_one_device(vol->name, MS_RDONLY,
468 &btrfs_fs_type, &fs_devices);
476 static void btrfs_write_super_lockfs(struct super_block *sb)
478 struct btrfs_root *root = btrfs_sb(sb);
479 btrfs_transaction_flush_work(root);
482 static void btrfs_unlockfs(struct super_block *sb)
484 struct btrfs_root *root = btrfs_sb(sb);
485 btrfs_transaction_queue_work(root, HZ * 30);
488 static struct super_operations btrfs_super_ops = {
489 .delete_inode = btrfs_delete_inode,
490 .put_inode = btrfs_put_inode,
491 .put_super = btrfs_put_super,
492 .write_super = btrfs_write_super,
493 .sync_fs = btrfs_sync_fs,
494 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25)
495 .read_inode = btrfs_read_locked_inode,
497 .show_options = generic_show_options,
499 .write_inode = btrfs_write_inode,
500 .dirty_inode = btrfs_dirty_inode,
501 .alloc_inode = btrfs_alloc_inode,
502 .destroy_inode = btrfs_destroy_inode,
503 .statfs = btrfs_statfs,
504 .write_super_lockfs = btrfs_write_super_lockfs,
505 .unlockfs = btrfs_unlockfs,
508 static const struct file_operations btrfs_ctl_fops = {
509 .unlocked_ioctl = btrfs_control_ioctl,
510 .compat_ioctl = btrfs_control_ioctl,
511 .owner = THIS_MODULE,
514 static struct miscdevice btrfs_misc = {
515 .minor = MISC_DYNAMIC_MINOR,
516 .name = "btrfs-control",
517 .fops = &btrfs_ctl_fops
520 static int btrfs_interface_init(void)
522 return misc_register(&btrfs_misc);
525 void btrfs_interface_exit(void)
527 if (misc_deregister(&btrfs_misc) < 0)
528 printk("misc_deregister failed for control device");
531 static int __init init_btrfs_fs(void)
535 err = btrfs_init_sysfs();
539 btrfs_init_transaction_sys();
540 err = btrfs_init_cachep();
542 goto free_transaction_sys;
544 err = extent_io_init();
548 err = extent_map_init();
552 err = btrfs_interface_init();
554 goto free_extent_map;
555 err = register_filesystem(&btrfs_fs_type);
557 goto unregister_ioctl;
561 btrfs_interface_exit();
567 btrfs_destroy_cachep();
568 free_transaction_sys:
569 btrfs_exit_transaction_sys();
574 static void __exit exit_btrfs_fs(void)
576 btrfs_exit_transaction_sys();
577 btrfs_destroy_cachep();
580 btrfs_interface_exit();
581 unregister_filesystem(&btrfs_fs_type);
583 btrfs_cleanup_fs_uuids();
586 module_init(init_btrfs_fs)
587 module_exit(exit_btrfs_fs)
589 MODULE_LICENSE("GPL");