1 #include <linux/module.h>
2 #include <linux/buffer_head.h>
4 #include <linux/pagemap.h>
5 #include <linux/highmem.h>
6 #include <linux/time.h>
7 #include <linux/init.h>
8 #include <linux/string.h>
9 #include <linux/smp_lock.h>
10 #include <linux/backing-dev.h>
11 #include <linux/mpage.h>
14 #include "transaction.h"
16 #define BTRFS_SUPER_MAGIC 0x9123682E
18 static struct inode_operations btrfs_dir_inode_operations;
19 static struct super_operations btrfs_super_ops;
20 static struct file_operations btrfs_dir_file_operations;
21 static struct inode_operations btrfs_file_inode_operations;
22 static struct address_space_operations btrfs_aops;
23 static struct file_operations btrfs_file_operations;
25 static void btrfs_read_locked_inode(struct inode *inode)
27 struct btrfs_path path;
28 struct btrfs_inode_item *inode_item;
29 struct btrfs_root *root = btrfs_sb(inode->i_sb);
31 btrfs_init_path(&path);
32 ret = btrfs_lookup_inode(NULL, root, &path, inode->i_ino, 0);
34 make_bad_inode(inode);
35 btrfs_release_path(root, &path);
38 inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]),
40 struct btrfs_inode_item);
42 inode->i_mode = btrfs_inode_mode(inode_item);
43 inode->i_nlink = btrfs_inode_nlink(inode_item);
44 inode->i_uid = btrfs_inode_uid(inode_item);
45 inode->i_gid = btrfs_inode_gid(inode_item);
46 inode->i_size = btrfs_inode_size(inode_item);
47 inode->i_atime.tv_sec = btrfs_timespec_sec(&inode_item->atime);
48 inode->i_atime.tv_nsec = btrfs_timespec_nsec(&inode_item->atime);
49 inode->i_mtime.tv_sec = btrfs_timespec_sec(&inode_item->mtime);
50 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(&inode_item->mtime);
51 inode->i_ctime.tv_sec = btrfs_timespec_sec(&inode_item->ctime);
52 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(&inode_item->ctime);
53 inode->i_blocks = btrfs_inode_nblocks(inode_item);
54 inode->i_generation = btrfs_inode_generation(inode_item);
55 btrfs_release_path(root, &path);
56 switch (inode->i_mode & S_IFMT) {
59 init_special_inode(inode, inode->i_mode,
60 btrfs_inode_rdev(inode_item));
64 inode->i_mapping->a_ops = &btrfs_aops;
65 inode->i_fop = &btrfs_file_operations;
66 inode->i_op = &btrfs_file_inode_operations;
69 inode->i_op = &btrfs_dir_inode_operations;
70 inode->i_fop = &btrfs_dir_file_operations;
73 // inode->i_op = &page_symlink_inode_operations;
79 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
81 struct btrfs_path path;
82 struct btrfs_root *root;
83 struct btrfs_trans_handle *trans;
84 const char *name = dentry->d_name.name;
85 int name_len = dentry->d_name.len;
88 struct btrfs_dir_item *di;
90 btrfs_init_path(&path);
91 root = btrfs_sb(dir->i_sb);
92 mutex_lock(&root->fs_info->fs_mutex);
93 trans = btrfs_start_transaction(root, 1);
95 ret = btrfs_lookup_dir_item(trans, root, &path, dir->i_ino,
103 di = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
104 struct btrfs_dir_item);
105 objectid = btrfs_dir_objectid(di);
107 ret = btrfs_del_item(trans, root, &path);
109 dentry->d_inode->i_ctime = dir->i_ctime;
111 btrfs_release_path(root, &path);
112 btrfs_end_transaction(trans, root);
113 mutex_unlock(&root->fs_info->fs_mutex);
115 inode_dec_link_count(dentry->d_inode);
119 static int btrfs_free_inode(struct btrfs_trans_handle *trans,
120 struct btrfs_root *root,
123 u64 objectid = inode->i_ino;
124 struct btrfs_path path;
125 struct btrfs_inode_map_item *map;
126 struct btrfs_key stat_data_key;
129 btrfs_init_path(&path);
130 ret = btrfs_lookup_inode_map(trans, root, &path, objectid, -1);
134 btrfs_release_path(root, &path);
137 map = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
138 struct btrfs_inode_map_item);
139 btrfs_disk_key_to_cpu(&stat_data_key, &map->key);
140 ret = btrfs_del_item(trans, root->fs_info->inode_root, &path);
142 btrfs_release_path(root, &path);
143 btrfs_init_path(&path);
145 ret = btrfs_lookup_inode(trans, root, &path, objectid, -1);
147 ret = btrfs_del_item(trans, root, &path);
149 btrfs_release_path(root, &path);
154 static void btrfs_delete_inode(struct inode *inode)
156 struct btrfs_trans_handle *trans;
157 struct btrfs_root *root = btrfs_sb(inode->i_sb);
158 truncate_inode_pages(&inode->i_data, 0);
159 if (is_bad_inode(inode)) {
166 mutex_lock(&root->fs_info->fs_mutex);
167 trans = btrfs_start_transaction(root, 1);
168 btrfs_free_inode(trans, root, inode);
169 btrfs_end_transaction(trans, root);
170 mutex_unlock(&root->fs_info->fs_mutex);
177 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
180 const char *name = dentry->d_name.name;
181 int namelen = dentry->d_name.len;
182 struct btrfs_dir_item *di;
183 struct btrfs_path path;
184 struct btrfs_root *root = btrfs_sb(dir->i_sb);
187 btrfs_init_path(&path);
188 ret = btrfs_lookup_dir_item(NULL, root, &path, dir->i_ino, name,
190 if (ret || !btrfs_match_dir_item_name(root, &path, name, namelen)) {
194 di = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
195 struct btrfs_dir_item);
196 *ino = btrfs_dir_objectid(di);
198 btrfs_release_path(root, &path);
202 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
203 struct nameidata *nd)
205 struct inode * inode;
209 if (dentry->d_name.len > BTRFS_NAME_LEN)
210 return ERR_PTR(-ENAMETOOLONG);
212 ret = btrfs_inode_by_name(dir, dentry, &ino);
217 inode = iget(dir->i_sb, ino);
219 return ERR_PTR(-EACCES);
221 return d_splice_alias(inode, dentry);
224 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
226 struct inode *inode = filp->f_path.dentry->d_inode;
227 struct btrfs_root *root = btrfs_sb(inode->i_sb);
228 struct btrfs_item *item;
229 struct btrfs_dir_item *di;
230 struct btrfs_key key;
231 struct btrfs_path path;
234 struct btrfs_leaf *leaf;
237 unsigned char d_type = DT_UNKNOWN;
240 key.objectid = inode->i_ino;
242 btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
243 key.offset = filp->f_pos;
244 btrfs_init_path(&path);
245 ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
251 leaf = btrfs_buffer_leaf(path.nodes[0]);
252 nritems = btrfs_header_nritems(&leaf->header);
253 slot = path.slots[0];
254 if (advance || slot >= nritems) {
255 if (slot >= nritems -1) {
256 ret = btrfs_next_leaf(root, &path);
259 leaf = btrfs_buffer_leaf(path.nodes[0]);
260 nritems = btrfs_header_nritems(&leaf->header);
261 slot = path.slots[0];
268 item = leaf->items + slot;
269 if (btrfs_disk_key_objectid(&item->key) != key.objectid)
271 if (btrfs_disk_key_type(&item->key) != BTRFS_DIR_ITEM_KEY)
273 if (btrfs_disk_key_offset(&item->key) < filp->f_pos)
277 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
278 over = filldir(dirent, (const char *)(di + 1),
279 btrfs_dir_name_len(di),
280 btrfs_disk_key_offset(&item->key),
281 btrfs_dir_objectid(di), d_type);
283 filp->f_pos = btrfs_disk_key_offset(&item->key);
286 filp->f_pos = btrfs_disk_key_offset(&item->key) + 1;
290 btrfs_release_path(root, &path);
294 static void btrfs_put_super (struct super_block * sb)
296 struct btrfs_root *root = btrfs_sb(sb);
299 ret = close_ctree(root);
301 printk("close ctree returns %d\n", ret);
303 sb->s_fs_info = NULL;
306 static int btrfs_fill_super(struct super_block * sb, void * data, int silent)
308 struct inode * inode;
309 struct dentry * root_dentry;
310 struct btrfs_super_block *disk_super;
311 struct buffer_head *bh;
312 struct btrfs_root *root;
314 sb->s_maxbytes = MAX_LFS_FILESIZE;
315 sb->s_blocksize = PAGE_CACHE_SIZE;
316 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
317 sb->s_magic = BTRFS_SUPER_MAGIC;
318 sb->s_op = &btrfs_super_ops;
321 bh = sb_bread(sb, BTRFS_SUPER_INFO_OFFSET / sb->s_blocksize);
323 printk("btrfs: unable to read on disk super\n");
326 disk_super = (struct btrfs_super_block *)bh->b_data;
327 root = open_ctree(sb, bh, disk_super);
328 sb->s_fs_info = root;
330 printk("btrfs: open_ctree failed\n");
333 printk("read in super total blocks %Lu root %Lu\n",
334 btrfs_super_total_blocks(disk_super),
335 btrfs_super_root_dir(disk_super));
337 inode = iget_locked(sb, btrfs_super_root_dir(disk_super));
340 if (inode->i_state & I_NEW) {
341 btrfs_read_locked_inode(inode);
342 unlock_new_inode(inode);
345 root_dentry = d_alloc_root(inode);
350 sb->s_root = root_dentry;
355 static void fill_inode_item(struct btrfs_inode_item *item,
358 btrfs_set_inode_uid(item, inode->i_uid);
359 btrfs_set_inode_gid(item, inode->i_gid);
360 btrfs_set_inode_size(item, inode->i_size);
361 btrfs_set_inode_mode(item, inode->i_mode);
362 btrfs_set_inode_nlink(item, inode->i_nlink);
363 btrfs_set_timespec_sec(&item->atime, inode->i_atime.tv_sec);
364 btrfs_set_timespec_nsec(&item->atime, inode->i_atime.tv_nsec);
365 btrfs_set_timespec_sec(&item->mtime, inode->i_mtime.tv_sec);
366 btrfs_set_timespec_nsec(&item->mtime, inode->i_mtime.tv_nsec);
367 btrfs_set_timespec_sec(&item->ctime, inode->i_ctime.tv_sec);
368 btrfs_set_timespec_nsec(&item->ctime, inode->i_ctime.tv_nsec);
369 btrfs_set_inode_nblocks(item, inode->i_blocks);
370 btrfs_set_inode_generation(item, inode->i_generation);
373 static int btrfs_update_inode(struct btrfs_trans_handle *trans,
374 struct btrfs_root *root,
377 struct btrfs_inode_item *inode_item;
378 struct btrfs_path path;
381 btrfs_init_path(&path);
383 ret = btrfs_lookup_inode(trans, root, &path, inode->i_ino, 1);
390 inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]),
392 struct btrfs_inode_item);
394 fill_inode_item(inode_item, inode);
395 mark_buffer_dirty(path.nodes[0]);
397 btrfs_release_path(root, &path);
401 static int btrfs_write_inode(struct inode *inode, int wait)
403 struct btrfs_root *root = btrfs_sb(inode->i_sb);
404 struct btrfs_trans_handle *trans;
407 mutex_lock(&root->fs_info->fs_mutex);
408 trans = btrfs_start_transaction(root, 1);
409 ret = btrfs_update_inode(trans, root, inode);
411 btrfs_commit_transaction(trans, root);
413 btrfs_end_transaction(trans, root);
414 mutex_unlock(&root->fs_info->fs_mutex);
418 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
419 struct inode *dir, int mode)
422 struct btrfs_inode_item inode_item;
423 struct btrfs_root *root = btrfs_sb(dir->i_sb);
424 struct btrfs_key key;
428 inode = new_inode(dir->i_sb);
430 return ERR_PTR(-ENOMEM);
432 ret = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
435 inode->i_uid = current->fsuid;
436 inode->i_gid = current->fsgid;
437 inode->i_mode = mode;
438 inode->i_ino = objectid;
440 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
441 fill_inode_item(&inode_item, inode);
443 key.objectid = objectid;
446 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
447 ret = btrfs_insert_inode_map(trans, root, objectid, &key);
450 ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
453 insert_inode_hash(inode);
457 static int btrfs_add_link(struct btrfs_trans_handle *trans,
458 struct dentry *dentry, struct inode *inode)
461 ret = btrfs_insert_dir_item(trans, btrfs_sb(inode->i_sb),
462 dentry->d_name.name, dentry->d_name.len,
463 dentry->d_parent->d_inode->i_ino,
466 dentry->d_parent->d_inode->i_size += dentry->d_name.len;
467 ret = btrfs_update_inode(trans, btrfs_sb(inode->i_sb),
468 dentry->d_parent->d_inode);
474 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
475 struct dentry *dentry, struct inode *inode)
477 int err = btrfs_add_link(trans, dentry, inode);
479 d_instantiate(dentry, inode);
485 static int btrfs_create(struct inode *dir, struct dentry *dentry,
486 int mode, struct nameidata *nd)
488 struct btrfs_trans_handle *trans;
489 struct btrfs_root *root = btrfs_sb(dir->i_sb);
494 mutex_lock(&root->fs_info->fs_mutex);
495 trans = btrfs_start_transaction(root, 1);
496 inode = btrfs_new_inode(trans, dir, mode);
497 err = PTR_ERR(inode);
500 // FIXME mark the inode dirty
501 err = btrfs_add_nondir(trans, dentry, inode);
505 inode->i_mapping->a_ops = &btrfs_aops;
506 inode->i_fop = &btrfs_file_operations;
507 inode->i_op = &btrfs_file_inode_operations;
509 dir->i_sb->s_dirt = 1;
510 btrfs_end_transaction(trans, root);
512 mutex_unlock(&root->fs_info->fs_mutex);
514 inode_dec_link_count(inode);
520 static int btrfs_make_empty_dir(struct btrfs_trans_handle *trans,
521 struct inode *inode, struct inode *dir)
523 struct btrfs_root *root = btrfs_sb(inode->i_sb);
529 ret = btrfs_insert_dir_item(trans, root, buf, 1, inode->i_ino,
533 ret = btrfs_insert_dir_item(trans, root, buf, 2, inode->i_ino,
538 ret = btrfs_update_inode(trans, root, inode);
543 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
546 struct btrfs_trans_handle *trans;
547 struct btrfs_root *root = btrfs_sb(dir->i_sb);
551 mutex_lock(&root->fs_info->fs_mutex);
552 trans = btrfs_start_transaction(root, 1);
554 err = PTR_ERR(trans);
557 inode = btrfs_new_inode(trans, dir, S_IFDIR | mode);
559 err = PTR_ERR(inode);
563 inode->i_op = &btrfs_dir_inode_operations;
564 inode->i_fop = &btrfs_dir_file_operations;
566 err = btrfs_make_empty_dir(trans, inode, dir);
569 err = btrfs_add_link(trans, dentry, inode);
572 d_instantiate(dentry, inode);
576 btrfs_end_transaction(trans, root);
578 mutex_unlock(&root->fs_info->fs_mutex);
584 static int btrfs_sync_fs(struct super_block *sb, int wait)
586 struct btrfs_trans_handle *trans;
587 struct btrfs_root *root;
592 filemap_flush(sb->s_bdev->bd_inode->i_mapping);
595 filemap_write_and_wait(sb->s_bdev->bd_inode->i_mapping);
598 mutex_lock(&root->fs_info->fs_mutex);
599 trans = btrfs_start_transaction(root, 1);
600 ret = btrfs_commit_transaction(trans, root);
603 printk("btrfs sync_fs\n");
604 mutex_unlock(&root->fs_info->fs_mutex);
608 static int btrfs_get_block(struct inode *inode, sector_t iblock,
609 struct buffer_head *result, int create)
614 u64 extent_start = 0;
616 u64 objectid = inode->i_ino;
617 struct btrfs_path path;
618 struct btrfs_root *root = btrfs_sb(inode->i_sb);
619 struct btrfs_trans_handle *trans = NULL;
620 struct btrfs_file_extent_item *item;
621 struct btrfs_leaf *leaf;
622 struct btrfs_disk_key *found_key;
624 btrfs_init_path(&path);
625 mutex_lock(&root->fs_info->fs_mutex);
627 trans = btrfs_start_transaction(root, 1);
630 ret = btrfs_lookup_file_extent(trans, root, &path,
631 inode->i_ino, iblock, 1, 0);
633 btrfs_release_path(root, &path);
639 if (path.slots[0] == 0) {
640 btrfs_release_path(root, &path);
646 item = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
647 struct btrfs_file_extent_item);
648 leaf = btrfs_buffer_leaf(path.nodes[0]);
649 blocknr = btrfs_file_extent_disk_blocknr(item);
650 blocknr += btrfs_file_extent_offset(item);
652 /* exact match found, use it */
655 map_bh(result, inode->i_sb, blocknr);
656 btrfs_release_path(root, &path);
660 /* are we inside the extent that was found? */
661 found_key = &leaf->items[path.slots[0]].key;
662 if (btrfs_disk_key_objectid(found_key) != objectid ||
663 btrfs_disk_key_type(found_key) != BTRFS_EXTENT_DATA_KEY) {
666 btrfs_release_path(root, &path);
670 extent_start = btrfs_disk_key_offset(&leaf->items[path.slots[0]].key);
671 extent_start += btrfs_file_extent_offset(item);
672 extent_end = extent_start + btrfs_file_extent_num_blocks(item);
673 btrfs_release_path(root, &path);
674 if (iblock >= extent_start && iblock < extent_end) {
676 map_bh(result, inode->i_sb, blocknr + iblock - extent_start);
680 /* ok, create a new extent */
685 ret = btrfs_alloc_file_extent(trans, root, objectid, iblock,
686 1, extent_end, &blocknr);
691 map_bh(result, inode->i_sb, blocknr);
695 btrfs_end_transaction(trans, root);
696 mutex_unlock(&root->fs_info->fs_mutex);
700 static int btrfs_prepare_write(struct file *file, struct page *page,
701 unsigned from, unsigned to)
703 return nobh_prepare_write(page, from, to, btrfs_get_block);
706 static void btrfs_write_super(struct super_block *sb)
708 btrfs_sync_fs(sb, 1);
711 static int btrfs_readpage(struct file *file, struct page *page)
713 return mpage_readpage(page, btrfs_get_block);
716 static int btrfs_readpages(struct file *file, struct address_space *mapping,
717 struct list_head *pages, unsigned nr_pages)
719 return mpage_readpages(mapping, pages, nr_pages, btrfs_get_block);
722 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
724 return nobh_writepage(page, btrfs_get_block, wbc);
727 static int btrfs_get_sb(struct file_system_type *fs_type,
728 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
730 return get_sb_bdev(fs_type, flags, dev_name, data,
731 btrfs_fill_super, mnt);
734 static struct file_system_type btrfs_fs_type = {
735 .owner = THIS_MODULE,
737 .get_sb = btrfs_get_sb,
738 .kill_sb = kill_block_super,
739 .fs_flags = FS_REQUIRES_DEV,
742 static struct super_operations btrfs_super_ops = {
743 .statfs = simple_statfs,
744 .delete_inode = btrfs_delete_inode,
745 .put_super = btrfs_put_super,
746 .read_inode = btrfs_read_locked_inode,
747 .write_super = btrfs_write_super,
748 .sync_fs = btrfs_sync_fs,
749 .write_inode = btrfs_write_inode,
752 static struct inode_operations btrfs_dir_inode_operations = {
753 .lookup = btrfs_lookup,
754 .create = btrfs_create,
755 .unlink = btrfs_unlink,
756 .mkdir = btrfs_mkdir,
759 static struct file_operations btrfs_dir_file_operations = {
760 .llseek = generic_file_llseek,
761 .read = generic_read_dir,
762 .readdir = btrfs_readdir,
765 static struct address_space_operations btrfs_aops = {
766 .readpage = btrfs_readpage,
767 .readpages = btrfs_readpages,
768 .writepage = btrfs_writepage,
769 .sync_page = block_sync_page,
770 .prepare_write = btrfs_prepare_write,
771 .commit_write = nobh_commit_write,
774 static struct inode_operations btrfs_file_inode_operations = {
778 static struct file_operations btrfs_file_operations = {
779 .llseek = generic_file_llseek,
780 .read = do_sync_read,
781 .write = do_sync_write,
782 .aio_read = generic_file_aio_read,
783 .aio_write = generic_file_aio_write,
784 .mmap = generic_file_mmap,
785 .open = generic_file_open,
786 .sendfile = generic_file_sendfile,
787 .splice_read = generic_file_splice_read,
788 .splice_write = generic_file_splice_write,
791 static int __init init_btrfs_fs(void)
793 printk("btrfs loaded!\n");
794 return register_filesystem(&btrfs_fs_type);
797 static void __exit exit_btrfs_fs(void)
799 unregister_filesystem(&btrfs_fs_type);
800 printk("btrfs unloaded\n");
803 module_init(init_btrfs_fs)
804 module_exit(exit_btrfs_fs)
806 MODULE_LICENSE("GPL");