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>
12 #include <linux/swap.h>
13 #include <linux/writeback.h>
16 #include "transaction.h"
17 #include "btrfs_inode.h"
20 void btrfs_fsinfo_release(struct kobject *obj)
22 struct btrfs_fs_info *fsinfo = container_of(obj,
23 struct btrfs_fs_info, kobj);
27 struct kobj_type btrfs_fsinfo_ktype = {
28 .release = btrfs_fsinfo_release,
31 struct btrfs_iget_args {
33 struct btrfs_root *root;
36 decl_subsys(btrfs, &btrfs_fsinfo_ktype, NULL);
38 #define BTRFS_SUPER_MAGIC 0x9123682E
40 static struct inode_operations btrfs_dir_inode_operations;
41 static struct inode_operations btrfs_dir_ro_inode_operations;
42 static struct super_operations btrfs_super_ops;
43 static struct file_operations btrfs_dir_file_operations;
44 static struct inode_operations btrfs_file_inode_operations;
45 static struct address_space_operations btrfs_aops;
46 static struct file_operations btrfs_file_operations;
48 static void btrfs_read_locked_inode(struct inode *inode)
50 struct btrfs_path *path;
51 struct btrfs_inode_item *inode_item;
52 struct btrfs_root *root = BTRFS_I(inode)->root;
53 struct btrfs_key location;
56 path = btrfs_alloc_path();
58 btrfs_init_path(path);
59 mutex_lock(&root->fs_info->fs_mutex);
61 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
62 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
64 btrfs_free_path(path);
67 inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
69 struct btrfs_inode_item);
71 inode->i_mode = btrfs_inode_mode(inode_item);
72 inode->i_nlink = btrfs_inode_nlink(inode_item);
73 inode->i_uid = btrfs_inode_uid(inode_item);
74 inode->i_gid = btrfs_inode_gid(inode_item);
75 inode->i_size = btrfs_inode_size(inode_item);
76 inode->i_atime.tv_sec = btrfs_timespec_sec(&inode_item->atime);
77 inode->i_atime.tv_nsec = btrfs_timespec_nsec(&inode_item->atime);
78 inode->i_mtime.tv_sec = btrfs_timespec_sec(&inode_item->mtime);
79 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(&inode_item->mtime);
80 inode->i_ctime.tv_sec = btrfs_timespec_sec(&inode_item->ctime);
81 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(&inode_item->ctime);
82 inode->i_blocks = btrfs_inode_nblocks(inode_item);
83 inode->i_generation = btrfs_inode_generation(inode_item);
85 btrfs_free_path(path);
88 mutex_unlock(&root->fs_info->fs_mutex);
90 switch (inode->i_mode & S_IFMT) {
93 init_special_inode(inode, inode->i_mode,
94 btrfs_inode_rdev(inode_item));
98 inode->i_mapping->a_ops = &btrfs_aops;
99 inode->i_fop = &btrfs_file_operations;
100 inode->i_op = &btrfs_file_inode_operations;
103 inode->i_fop = &btrfs_dir_file_operations;
104 if (root == root->fs_info->tree_root)
105 inode->i_op = &btrfs_dir_ro_inode_operations;
107 inode->i_op = &btrfs_dir_inode_operations;
110 // inode->i_op = &page_symlink_inode_operations;
116 btrfs_release_path(root, path);
117 btrfs_free_path(path);
118 mutex_unlock(&root->fs_info->fs_mutex);
119 make_bad_inode(inode);
122 static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
123 struct btrfs_root *root,
125 struct dentry *dentry)
127 struct btrfs_path *path;
128 const char *name = dentry->d_name.name;
129 int name_len = dentry->d_name.len;
132 struct btrfs_dir_item *di;
134 path = btrfs_alloc_path();
136 btrfs_init_path(path);
137 ret = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
145 di = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
146 struct btrfs_dir_item);
147 objectid = btrfs_disk_key_objectid(&di->location);
149 ret = btrfs_del_item(trans, root, path);
152 btrfs_release_path(root, path);
153 ret = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
156 ret = btrfs_del_item(trans, root, path);
158 dentry->d_inode->i_ctime = dir->i_ctime;
160 btrfs_release_path(root, path);
161 btrfs_free_path(path);
163 inode_dec_link_count(dentry->d_inode);
164 dir->i_size -= name_len * 2;
165 mark_inode_dirty(dir);
170 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
172 struct btrfs_root *root;
173 struct btrfs_trans_handle *trans;
176 root = BTRFS_I(dir)->root;
177 mutex_lock(&root->fs_info->fs_mutex);
178 trans = btrfs_start_transaction(root, 1);
179 ret = btrfs_unlink_trans(trans, root, dir, dentry);
180 btrfs_end_transaction(trans, root);
181 mutex_unlock(&root->fs_info->fs_mutex);
185 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
187 struct inode *inode = dentry->d_inode;
190 struct btrfs_root *root = BTRFS_I(dir)->root;
191 struct btrfs_path *path;
192 struct btrfs_key key;
193 struct btrfs_trans_handle *trans;
194 struct btrfs_key found_key;
196 struct btrfs_leaf *leaf;
197 char *goodnames = "..";
199 path = btrfs_alloc_path();
201 btrfs_init_path(path);
202 mutex_lock(&root->fs_info->fs_mutex);
203 trans = btrfs_start_transaction(root, 1);
204 key.objectid = inode->i_ino;
205 key.offset = (u64)-1;
208 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
214 if (path->slots[0] == 0) {
219 leaf = btrfs_buffer_leaf(path->nodes[0]);
220 btrfs_disk_key_to_cpu(&found_key,
221 &leaf->items[path->slots[0]].key);
222 found_type = btrfs_key_type(&found_key);
223 if (found_key.objectid != inode->i_ino) {
227 if ((found_type != BTRFS_DIR_ITEM_KEY &&
228 found_type != BTRFS_DIR_INDEX_KEY) ||
229 (!btrfs_match_dir_item_name(root, path, goodnames, 2) &&
230 !btrfs_match_dir_item_name(root, path, goodnames, 1))) {
234 ret = btrfs_del_item(trans, root, path);
237 if (found_type == BTRFS_DIR_ITEM_KEY && found_key.offset == 1)
239 btrfs_release_path(root, path);
242 btrfs_release_path(root, path);
244 /* now the directory is empty */
245 err = btrfs_unlink_trans(trans, root, dir, dentry);
250 btrfs_release_path(root, path);
251 btrfs_free_path(path);
252 mutex_unlock(&root->fs_info->fs_mutex);
253 ret = btrfs_end_transaction(trans, root);
259 static int btrfs_free_inode(struct btrfs_trans_handle *trans,
260 struct btrfs_root *root,
263 struct btrfs_path *path;
268 path = btrfs_alloc_path();
270 btrfs_init_path(path);
271 ret = btrfs_lookup_inode(trans, root, path,
272 &BTRFS_I(inode)->location, -1);
274 ret = btrfs_del_item(trans, root, path);
276 btrfs_free_path(path);
280 static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
281 struct btrfs_root *root,
285 struct btrfs_path *path;
286 struct btrfs_key key;
287 struct btrfs_disk_key *found_key;
288 struct btrfs_leaf *leaf;
289 struct btrfs_file_extent_item *fi = NULL;
290 u64 extent_start = 0;
291 u64 extent_num_blocks = 0;
294 path = btrfs_alloc_path();
296 /* FIXME, add redo link to tree so we don't leak on crash */
297 key.objectid = inode->i_ino;
298 key.offset = (u64)-1;
301 * use BTRFS_CSUM_ITEM_KEY because it is larger than inline keys
304 btrfs_set_key_type(&key, BTRFS_CSUM_ITEM_KEY);
306 btrfs_init_path(path);
307 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
312 BUG_ON(path->slots[0] == 0);
315 leaf = btrfs_buffer_leaf(path->nodes[0]);
316 found_key = &leaf->items[path->slots[0]].key;
317 if (btrfs_disk_key_objectid(found_key) != inode->i_ino)
319 if (btrfs_disk_key_type(found_key) != BTRFS_CSUM_ITEM_KEY &&
320 btrfs_disk_key_type(found_key) != BTRFS_INLINE_DATA_KEY &&
321 btrfs_disk_key_type(found_key) != BTRFS_EXTENT_DATA_KEY)
323 if (btrfs_disk_key_offset(found_key) < inode->i_size)
325 if (btrfs_disk_key_type(found_key) == BTRFS_EXTENT_DATA_KEY) {
326 fi = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
328 struct btrfs_file_extent_item);
329 extent_start = btrfs_file_extent_disk_blocknr(fi);
331 btrfs_file_extent_disk_num_blocks(fi);
333 btrfs_file_extent_num_blocks(fi) >> 9;
338 ret = btrfs_del_item(trans, root, path);
340 btrfs_release_path(root, path);
342 ret = btrfs_free_extent(trans, root, extent_start,
343 extent_num_blocks, 0);
349 btrfs_release_path(root, path);
350 btrfs_free_path(path);
354 static void btrfs_delete_inode(struct inode *inode)
356 struct btrfs_trans_handle *trans;
357 struct btrfs_root *root = BTRFS_I(inode)->root;
360 truncate_inode_pages(&inode->i_data, 0);
361 if (is_bad_inode(inode)) {
365 mutex_lock(&root->fs_info->fs_mutex);
366 trans = btrfs_start_transaction(root, 1);
367 if (S_ISREG(inode->i_mode)) {
368 ret = btrfs_truncate_in_trans(trans, root, inode);
371 btrfs_free_inode(trans, root, inode);
372 btrfs_end_transaction(trans, root);
373 mutex_unlock(&root->fs_info->fs_mutex);
379 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
380 struct btrfs_key *location)
382 const char *name = dentry->d_name.name;
383 int namelen = dentry->d_name.len;
384 struct btrfs_dir_item *di;
385 struct btrfs_path *path;
386 struct btrfs_root *root = BTRFS_I(dir)->root;
389 path = btrfs_alloc_path();
391 btrfs_init_path(path);
392 ret = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
394 if (ret || !btrfs_match_dir_item_name(root, path, name, namelen)) {
395 location->objectid = 0;
399 di = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
400 struct btrfs_dir_item);
401 btrfs_disk_key_to_cpu(location, &di->location);
403 btrfs_release_path(root, path);
404 btrfs_free_path(path);
408 int fixup_tree_root_location(struct btrfs_root *root,
409 struct btrfs_key *location,
410 struct btrfs_root **sub_root)
412 struct btrfs_path *path;
413 struct btrfs_root_item *ri;
415 if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
417 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
420 path = btrfs_alloc_path();
422 mutex_lock(&root->fs_info->fs_mutex);
424 *sub_root = btrfs_read_fs_root(root->fs_info, location);
425 if (IS_ERR(*sub_root))
426 return PTR_ERR(*sub_root);
428 ri = &(*sub_root)->root_item;
429 location->objectid = btrfs_root_dirid(ri);
431 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
432 location->offset = 0;
434 btrfs_free_path(path);
435 mutex_unlock(&root->fs_info->fs_mutex);
439 int btrfs_init_locked_inode(struct inode *inode, void *p)
441 struct btrfs_iget_args *args = p;
442 inode->i_ino = args->ino;
443 BTRFS_I(inode)->root = args->root;
447 int btrfs_find_actor(struct inode *inode, void *opaque)
449 struct btrfs_iget_args *args = opaque;
450 return (args->ino == inode->i_ino &&
451 args->root == BTRFS_I(inode)->root);
454 struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
455 struct btrfs_root *root)
458 struct btrfs_iget_args args;
462 inode = iget5_locked(s, objectid, btrfs_find_actor,
463 btrfs_init_locked_inode,
468 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
469 struct nameidata *nd)
471 struct inode * inode;
472 struct btrfs_inode *bi = BTRFS_I(dir);
473 struct btrfs_root *root = bi->root;
474 struct btrfs_root *sub_root = root;
475 struct btrfs_key location;
478 if (dentry->d_name.len > BTRFS_NAME_LEN)
479 return ERR_PTR(-ENAMETOOLONG);
480 mutex_lock(&root->fs_info->fs_mutex);
481 ret = btrfs_inode_by_name(dir, dentry, &location);
482 mutex_unlock(&root->fs_info->fs_mutex);
486 if (location.objectid) {
487 ret = fixup_tree_root_location(root, &location, &sub_root);
491 return ERR_PTR(-ENOENT);
492 inode = btrfs_iget_locked(dir->i_sb, location.objectid,
495 return ERR_PTR(-EACCES);
496 if (inode->i_state & I_NEW) {
497 if (sub_root != root) {
498 printk("adding new root for inode %lu root %p (found %p)\n", inode->i_ino, sub_root, BTRFS_I(inode)->root);
500 sub_root->inode = inode;
502 BTRFS_I(inode)->root = sub_root;
503 memcpy(&BTRFS_I(inode)->location, &location,
505 btrfs_read_locked_inode(inode);
506 unlock_new_inode(inode);
509 return d_splice_alias(inode, dentry);
512 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
514 struct inode *inode = filp->f_path.dentry->d_inode;
515 struct btrfs_root *root = BTRFS_I(inode)->root;
516 struct btrfs_item *item;
517 struct btrfs_dir_item *di;
518 struct btrfs_key key;
519 struct btrfs_path *path;
522 struct btrfs_leaf *leaf;
525 unsigned char d_type = DT_UNKNOWN;
527 int key_type = BTRFS_DIR_INDEX_KEY;
529 /* FIXME, use a real flag for deciding about the key type */
530 if (root->fs_info->tree_root == root)
531 key_type = BTRFS_DIR_ITEM_KEY;
532 mutex_lock(&root->fs_info->fs_mutex);
533 key.objectid = inode->i_ino;
535 btrfs_set_key_type(&key, key_type);
536 key.offset = filp->f_pos;
537 path = btrfs_alloc_path();
538 btrfs_init_path(path);
539 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
544 leaf = btrfs_buffer_leaf(path->nodes[0]);
545 nritems = btrfs_header_nritems(&leaf->header);
546 slot = path->slots[0];
547 if (advance || slot >= nritems) {
548 if (slot >= nritems -1) {
549 ret = btrfs_next_leaf(root, path);
552 leaf = btrfs_buffer_leaf(path->nodes[0]);
553 nritems = btrfs_header_nritems(&leaf->header);
554 slot = path->slots[0];
561 item = leaf->items + slot;
562 if (btrfs_disk_key_objectid(&item->key) != key.objectid)
564 if (key_type == BTRFS_DIR_INDEX_KEY &&
565 btrfs_disk_key_offset(&item->key) > root->highest_inode)
567 if (btrfs_disk_key_type(&item->key) != key_type)
569 if (btrfs_disk_key_offset(&item->key) < filp->f_pos)
571 filp->f_pos = btrfs_disk_key_offset(&item->key);
573 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
574 over = filldir(dirent, (const char *)(di + 1),
575 btrfs_dir_name_len(di),
576 btrfs_disk_key_offset(&item->key),
577 btrfs_disk_key_objectid(&di->location), d_type);
585 btrfs_release_path(root, path);
586 btrfs_free_path(path);
587 mutex_unlock(&root->fs_info->fs_mutex);
591 static void btrfs_put_super (struct super_block * sb)
593 struct btrfs_root *root = btrfs_sb(sb);
596 ret = close_ctree(root);
598 printk("close ctree returns %d\n", ret);
600 sb->s_fs_info = NULL;
603 static int btrfs_fill_super(struct super_block * sb, void * data, int silent)
605 struct inode * inode;
606 struct dentry * root_dentry;
607 struct btrfs_super_block *disk_super;
608 struct btrfs_root *tree_root;
609 struct btrfs_inode *bi;
611 sb->s_maxbytes = MAX_LFS_FILESIZE;
612 sb->s_magic = BTRFS_SUPER_MAGIC;
613 sb->s_op = &btrfs_super_ops;
616 tree_root = open_ctree(sb);
619 printk("btrfs: open_ctree failed\n");
622 sb->s_fs_info = tree_root;
623 disk_super = tree_root->fs_info->disk_super;
624 printk("read in super total blocks %Lu root %Lu\n",
625 btrfs_super_total_blocks(disk_super),
626 btrfs_super_root_dir(disk_super));
628 inode = btrfs_iget_locked(sb, btrfs_super_root_dir(disk_super),
631 bi->location.objectid = inode->i_ino;
632 bi->location.offset = 0;
633 bi->location.flags = 0;
634 bi->root = tree_root;
635 btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY);
639 if (inode->i_state & I_NEW) {
640 btrfs_read_locked_inode(inode);
641 unlock_new_inode(inode);
644 root_dentry = d_alloc_root(inode);
649 sb->s_root = root_dentry;
654 static void fill_inode_item(struct btrfs_inode_item *item,
657 btrfs_set_inode_uid(item, inode->i_uid);
658 btrfs_set_inode_gid(item, inode->i_gid);
659 btrfs_set_inode_size(item, inode->i_size);
660 btrfs_set_inode_mode(item, inode->i_mode);
661 btrfs_set_inode_nlink(item, inode->i_nlink);
662 btrfs_set_timespec_sec(&item->atime, inode->i_atime.tv_sec);
663 btrfs_set_timespec_nsec(&item->atime, inode->i_atime.tv_nsec);
664 btrfs_set_timespec_sec(&item->mtime, inode->i_mtime.tv_sec);
665 btrfs_set_timespec_nsec(&item->mtime, inode->i_mtime.tv_nsec);
666 btrfs_set_timespec_sec(&item->ctime, inode->i_ctime.tv_sec);
667 btrfs_set_timespec_nsec(&item->ctime, inode->i_ctime.tv_nsec);
668 btrfs_set_inode_nblocks(item, inode->i_blocks);
669 btrfs_set_inode_generation(item, inode->i_generation);
672 static int btrfs_update_inode(struct btrfs_trans_handle *trans,
673 struct btrfs_root *root,
676 struct btrfs_inode_item *inode_item;
677 struct btrfs_path *path;
680 path = btrfs_alloc_path();
682 btrfs_init_path(path);
683 ret = btrfs_lookup_inode(trans, root, path,
684 &BTRFS_I(inode)->location, 1);
691 inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
693 struct btrfs_inode_item);
695 fill_inode_item(inode_item, inode);
696 btrfs_mark_buffer_dirty(path->nodes[0]);
699 btrfs_release_path(root, path);
700 btrfs_free_path(path);
704 static int btrfs_write_inode(struct inode *inode, int wait)
706 struct btrfs_root *root = BTRFS_I(inode)->root;
707 struct btrfs_trans_handle *trans;
710 mutex_lock(&root->fs_info->fs_mutex);
711 trans = btrfs_start_transaction(root, 1);
712 ret = btrfs_update_inode(trans, root, inode);
714 btrfs_commit_transaction(trans, root);
716 btrfs_end_transaction(trans, root);
717 mutex_unlock(&root->fs_info->fs_mutex);
721 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
722 struct btrfs_root *root,
723 u64 objectid, int mode)
726 struct btrfs_inode_item inode_item;
727 struct btrfs_key *location;
730 inode = new_inode(root->fs_info->sb);
732 return ERR_PTR(-ENOMEM);
734 BTRFS_I(inode)->root = root;
736 inode->i_uid = current->fsuid;
737 inode->i_gid = current->fsgid;
738 inode->i_mode = mode;
739 inode->i_ino = objectid;
741 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
742 fill_inode_item(&inode_item, inode);
743 location = &BTRFS_I(inode)->location;
744 location->objectid = objectid;
746 location->offset = 0;
747 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
749 ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
752 insert_inode_hash(inode);
756 static int btrfs_add_link(struct btrfs_trans_handle *trans,
757 struct dentry *dentry, struct inode *inode)
760 struct btrfs_key key;
761 struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
762 key.objectid = inode->i_ino;
764 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
767 ret = btrfs_insert_dir_item(trans, root,
768 dentry->d_name.name, dentry->d_name.len,
769 dentry->d_parent->d_inode->i_ino,
772 dentry->d_parent->d_inode->i_size += dentry->d_name.len * 2;
773 ret = btrfs_update_inode(trans, root,
774 dentry->d_parent->d_inode);
779 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
780 struct dentry *dentry, struct inode *inode)
782 int err = btrfs_add_link(trans, dentry, inode);
784 d_instantiate(dentry, inode);
792 static int btrfs_create(struct inode *dir, struct dentry *dentry,
793 int mode, struct nameidata *nd)
795 struct btrfs_trans_handle *trans;
796 struct btrfs_root *root = BTRFS_I(dir)->root;
802 mutex_lock(&root->fs_info->fs_mutex);
803 trans = btrfs_start_transaction(root, 1);
805 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
811 inode = btrfs_new_inode(trans, root, objectid, mode);
812 err = PTR_ERR(inode);
815 // FIXME mark the inode dirty
816 err = btrfs_add_nondir(trans, dentry, inode);
820 inode->i_mapping->a_ops = &btrfs_aops;
821 inode->i_fop = &btrfs_file_operations;
822 inode->i_op = &btrfs_file_inode_operations;
824 dir->i_sb->s_dirt = 1;
826 btrfs_end_transaction(trans, root);
827 mutex_unlock(&root->fs_info->fs_mutex);
830 inode_dec_link_count(inode);
836 static int btrfs_make_empty_dir(struct btrfs_trans_handle *trans,
837 struct btrfs_root *root,
838 u64 objectid, u64 dirid)
842 struct btrfs_key key;
847 key.objectid = objectid;
850 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
852 ret = btrfs_insert_dir_item(trans, root, buf, 1, objectid,
856 key.objectid = dirid;
857 ret = btrfs_insert_dir_item(trans, root, buf, 2, objectid,
865 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
868 struct btrfs_trans_handle *trans;
869 struct btrfs_root *root = BTRFS_I(dir)->root;
874 mutex_lock(&root->fs_info->fs_mutex);
875 trans = btrfs_start_transaction(root, 1);
877 err = PTR_ERR(trans);
881 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
887 inode = btrfs_new_inode(trans, root, objectid, S_IFDIR | mode);
889 err = PTR_ERR(inode);
893 inode->i_op = &btrfs_dir_inode_operations;
894 inode->i_fop = &btrfs_dir_file_operations;
896 err = btrfs_make_empty_dir(trans, root, inode->i_ino, dir->i_ino);
901 err = btrfs_update_inode(trans, root, inode);
904 err = btrfs_add_link(trans, dentry, inode);
907 d_instantiate(dentry, inode);
911 btrfs_end_transaction(trans, root);
913 mutex_unlock(&root->fs_info->fs_mutex);
919 static int btrfs_sync_fs(struct super_block *sb, int wait)
921 struct btrfs_trans_handle *trans;
922 struct btrfs_root *root;
928 filemap_flush(root->fs_info->btree_inode->i_mapping);
931 filemap_write_and_wait(root->fs_info->btree_inode->i_mapping);
932 mutex_lock(&root->fs_info->fs_mutex);
933 trans = btrfs_start_transaction(root, 1);
934 ret = btrfs_commit_transaction(trans, root);
937 printk("btrfs sync_fs\n");
938 mutex_unlock(&root->fs_info->fs_mutex);
943 static int btrfs_get_block_inline(struct inode *inode, sector_t iblock,
944 struct buffer_head *result, int create)
946 struct btrfs_root *root = btrfs_sb(inode->i_sb);
947 struct btrfs_path *path;
948 struct btrfs_key key;
949 struct btrfs_leaf *leaf;
950 int num_bytes = result->b_size;
960 path = btrfs_alloc_path();
967 pos = iblock << inode->i_blkbits;
968 key.objectid = inode->i_ino;
970 btrfs_set_key_type(&key, BTRFS_INLINE_DATA_KEY);
971 ptr = kmap(result->b_page);
973 ptr += (pos & (PAGE_CACHE_SIZE -1));
976 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
984 leaf = btrfs_buffer_leaf(path->nodes[0]);
985 item_size = btrfs_item_size(leaf->items + path->slots[0]);
986 copy_size = min(num_bytes, item_size);
987 data_ptr = btrfs_item_ptr(leaf, path->slots[0], char);
988 WARN_ON(safe_ptr + PAGE_CACHE_SIZE < ptr + copy_size);
989 memcpy(ptr, data_ptr, copy_size);
991 num_bytes -= copy_size;
992 WARN_ON(num_bytes < 0);
994 btrfs_release_path(root, path);
995 if (num_bytes != 0) {
996 if (pos >= i_size_read(inode))
997 memset(ptr, 0, num_bytes);
1001 set_buffer_uptodate(result);
1002 map_bh(result, inode->i_sb, 0);
1005 btrfs_free_path(path);
1006 kunmap(result->b_page);
1011 static int btrfs_get_block_lock(struct inode *inode, sector_t iblock,
1012 struct buffer_head *result, int create)
1017 u64 extent_start = 0;
1019 u64 objectid = inode->i_ino;
1020 struct btrfs_path *path;
1021 struct btrfs_root *root = BTRFS_I(inode)->root;
1022 struct btrfs_trans_handle *trans = NULL;
1023 struct btrfs_file_extent_item *item;
1024 struct btrfs_leaf *leaf;
1025 struct btrfs_disk_key *found_key;
1027 path = btrfs_alloc_path();
1029 btrfs_init_path(path);
1031 trans = btrfs_start_transaction(root, 1);
1033 ret = btrfs_lookup_file_extent(trans, root, path,
1035 iblock << inode->i_blkbits, create);
1042 if (path->slots[0] == 0) {
1043 btrfs_release_path(root, path);
1049 item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
1050 struct btrfs_file_extent_item);
1051 leaf = btrfs_buffer_leaf(path->nodes[0]);
1052 blocknr = btrfs_file_extent_disk_blocknr(item);
1053 blocknr += btrfs_file_extent_offset(item);
1055 /* exact match found, use it, FIXME, deal with extents
1056 * other than the page size
1060 BUG_ON(btrfs_file_extent_disk_num_blocks(item) != 1);
1062 btrfs_file_extent_generation(item) != trans->transid) {
1063 struct btrfs_key ins;
1064 ret = btrfs_alloc_extent(trans, root, 1,
1065 blocknr, (u64)-1, &ins);
1067 btrfs_set_file_extent_disk_blocknr(item, ins.objectid);
1068 mark_buffer_dirty(path->nodes[0]);
1069 ret = btrfs_free_extent(trans, root,
1072 blocknr = ins.objectid;
1075 map_bh(result, inode->i_sb, blocknr);
1079 /* are we inside the extent that was found? */
1080 found_key = &leaf->items[path->slots[0]].key;
1081 if (btrfs_disk_key_objectid(found_key) != objectid ||
1082 btrfs_disk_key_type(found_key) != BTRFS_EXTENT_DATA_KEY) {
1085 btrfs_release_path(root, path);
1089 extent_start = btrfs_disk_key_offset(&leaf->items[path->slots[0]].key);
1090 extent_start = extent_start >> inode->i_blkbits;
1091 extent_start += btrfs_file_extent_offset(item);
1092 extent_end = extent_start + btrfs_file_extent_num_blocks(item);
1093 if (iblock >= extent_start && iblock < extent_end) {
1095 map_bh(result, inode->i_sb, blocknr + iblock - extent_start);
1099 /* ok, create a new extent */
1104 ret = btrfs_alloc_file_extent(trans, root, objectid,
1105 iblock << inode->i_blkbits,
1106 1, extent_end, &blocknr);
1111 inode->i_blocks += inode->i_sb->s_blocksize >> 9;
1112 set_buffer_new(result);
1113 map_bh(result, inode->i_sb, blocknr);
1116 btrfs_release_path(root, path);
1117 btrfs_free_path(path);
1119 btrfs_end_transaction(trans, root);
1123 static int btrfs_get_block(struct inode *inode, sector_t iblock,
1124 struct buffer_head *result, int create)
1127 struct btrfs_root *root = BTRFS_I(inode)->root;
1128 mutex_lock(&root->fs_info->fs_mutex);
1129 err = btrfs_get_block_lock(inode, iblock, result, create);
1130 // err = btrfs_get_block_inline(inode, iblock, result, create);
1131 mutex_unlock(&root->fs_info->fs_mutex);
1135 static int btrfs_prepare_write(struct file *file, struct page *page,
1136 unsigned from, unsigned to)
1138 return nobh_prepare_write(page, from, to, btrfs_get_block);
1140 static int btrfs_commit_write(struct file *file, struct page *page,
1141 unsigned from, unsigned to)
1143 return nobh_commit_write(file, page, from, to);
1146 static void btrfs_write_super(struct super_block *sb)
1148 btrfs_sync_fs(sb, 1);
1151 static int btrfs_readpage(struct file *file, struct page *page)
1153 return mpage_readpage(page, btrfs_get_block);
1156 static int btrfs_readpages(struct file *file, struct address_space *mapping,
1157 struct list_head *pages, unsigned nr_pages)
1159 return mpage_readpages(mapping, pages, nr_pages, btrfs_get_block);
1162 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
1164 return nobh_writepage(page, btrfs_get_block, wbc);
1167 static void btrfs_truncate(struct inode *inode)
1169 struct btrfs_root *root = BTRFS_I(inode)->root;
1171 struct btrfs_trans_handle *trans;
1173 if (!S_ISREG(inode->i_mode))
1175 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
1178 nobh_truncate_page(inode->i_mapping, inode->i_size);
1180 /* FIXME, add redo link to tree so we don't leak on crash */
1181 mutex_lock(&root->fs_info->fs_mutex);
1182 trans = btrfs_start_transaction(root, 1);
1183 ret = btrfs_truncate_in_trans(trans, root, inode);
1185 ret = btrfs_end_transaction(trans, root);
1187 mutex_unlock(&root->fs_info->fs_mutex);
1188 mark_inode_dirty(inode);
1191 static int btrfs_copy_from_user(loff_t pos, int num_pages, int write_bytes,
1192 struct page **prepared_pages,
1193 const char __user * buf)
1195 long page_fault = 0;
1197 int offset = pos & (PAGE_CACHE_SIZE - 1);
1199 for (i = 0; i < num_pages && write_bytes > 0; i++, offset = 0) {
1200 size_t count = min_t(size_t,
1201 PAGE_CACHE_SIZE - offset, write_bytes);
1202 struct page *page = prepared_pages[i];
1203 fault_in_pages_readable(buf, count);
1205 /* Copy data from userspace to the current page */
1207 page_fault = __copy_from_user(page_address(page) + offset,
1209 /* Flush processor's dcache for this page */
1210 flush_dcache_page(page);
1213 write_bytes -= count;
1218 return page_fault ? -EFAULT : 0;
1221 static void btrfs_drop_pages(struct page **pages, size_t num_pages)
1224 for (i = 0; i < num_pages; i++) {
1227 unlock_page(pages[i]);
1228 mark_page_accessed(pages[i]);
1229 page_cache_release(pages[i]);
1232 static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
1233 struct btrfs_root *root,
1235 struct page **pages,
1245 struct inode *inode = file->f_path.dentry->d_inode;
1247 for (i = 0; i < num_pages; i++) {
1248 offset = pos & (PAGE_CACHE_SIZE -1);
1249 this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
1250 /* FIXME, one block at a time */
1252 mutex_lock(&root->fs_info->fs_mutex);
1253 trans = btrfs_start_transaction(root, 1);
1254 btrfs_csum_file_block(trans, root, inode->i_ino,
1255 pages[i]->index << PAGE_CACHE_SHIFT,
1256 kmap(pages[i]), PAGE_CACHE_SIZE);
1258 SetPageChecked(pages[i]);
1259 ret = btrfs_end_transaction(trans, root);
1261 mutex_unlock(&root->fs_info->fs_mutex);
1263 ret = nobh_commit_write(file, pages[i], offset,
1264 offset + this_write);
1270 WARN_ON(this_write > write_bytes);
1271 write_bytes -= this_write;
1277 static int prepare_pages(struct btrfs_trans_handle *trans,
1278 struct btrfs_root *root,
1280 struct page **pages,
1283 unsigned long first_index,
1284 unsigned long last_index,
1288 unsigned long index = pos >> PAGE_CACHE_SHIFT;
1289 struct inode *inode = file->f_path.dentry->d_inode;
1294 loff_t isize = i_size_read(inode);
1296 memset(pages, 0, num_pages * sizeof(struct page *));
1298 for (i = 0; i < num_pages; i++) {
1299 pages[i] = grab_cache_page(inode->i_mapping, index + i);
1302 goto failed_release;
1304 offset = pos & (PAGE_CACHE_SIZE -1);
1305 this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
1306 if (!PageUptodate(pages[i]) &&
1307 (pages[i]->index == first_index ||
1308 pages[i]->index == last_index) && pos < isize) {
1309 ret = mpage_readpage(pages[i], btrfs_get_block);
1311 lock_page(pages[i]);
1313 ret = nobh_prepare_write(pages[i], offset,
1314 offset + this_write,
1319 goto failed_truncate;
1321 WARN_ON(this_write > write_bytes);
1322 write_bytes -= this_write;
1327 btrfs_drop_pages(pages, num_pages);
1331 btrfs_drop_pages(pages, num_pages);
1333 vmtruncate(inode, isize);
1337 static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
1338 size_t count, loff_t *ppos)
1341 size_t num_written = 0;
1344 struct inode *inode = file->f_path.dentry->d_inode;
1345 struct btrfs_root *root = BTRFS_I(inode)->root;
1346 struct page *pages[1];
1347 unsigned long first_index;
1348 unsigned long last_index;
1350 if (file->f_flags & O_DIRECT)
1354 vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
1355 current->backing_dev_info = inode->i_mapping->backing_dev_info;
1356 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
1361 err = remove_suid(file->f_path.dentry);
1364 file_update_time(file);
1365 mutex_lock(&inode->i_mutex);
1366 first_index = pos >> PAGE_CACHE_SHIFT;
1367 last_index = (pos + count) >> PAGE_CACHE_SHIFT;
1369 size_t offset = pos & (PAGE_CACHE_SIZE - 1);
1370 size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset);
1371 size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
1373 ret = prepare_pages(NULL, root, file, pages, num_pages,
1374 pos, first_index, last_index, write_bytes);
1376 ret = btrfs_copy_from_user(pos, num_pages,
1377 write_bytes, pages, buf);
1380 ret = dirty_and_release_pages(NULL, root, file, pages,
1381 num_pages, pos, write_bytes);
1383 btrfs_drop_pages(pages, num_pages);
1386 count -= write_bytes;
1388 num_written += write_bytes;
1390 balance_dirty_pages_ratelimited(inode->i_mapping);
1393 mutex_unlock(&inode->i_mutex);
1396 current->backing_dev_info = NULL;
1397 return num_written ? num_written : err;
1401 static ssize_t inline_one_page(struct btrfs_root *root, struct inode *inode,
1402 struct page *page, loff_t pos,
1403 size_t offset, size_t write_bytes)
1405 struct btrfs_path *path;
1406 struct btrfs_trans_handle *trans;
1407 struct btrfs_key key;
1408 struct btrfs_leaf *leaf;
1409 struct btrfs_key found_key;
1411 size_t copy_size = 0;
1414 size_t num_written = 0;
1416 path = btrfs_alloc_path();
1418 mutex_lock(&root->fs_info->fs_mutex);
1419 trans = btrfs_start_transaction(root, 1);
1420 key.objectid = inode->i_ino;
1422 btrfs_set_key_type(&key, BTRFS_INLINE_DATA_KEY);
1426 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1432 leaf = btrfs_buffer_leaf(path->nodes[0]);
1433 btrfs_disk_key_to_cpu(&found_key,
1434 &leaf->items[path->slots[0]].key);
1435 copy_size = btrfs_item_size(leaf->items + path->slots[0]);
1436 dst = btrfs_item_ptr(leaf, path->slots[0], char);
1437 copy_size = min(write_bytes, copy_size);
1440 int slot = path->slots[0];
1444 // FIXME find max key
1445 leaf = btrfs_buffer_leaf(path->nodes[0]);
1446 btrfs_disk_key_to_cpu(&found_key,
1447 &leaf->items[slot].key);
1448 if (found_key.objectid != inode->i_ino)
1450 if (btrfs_key_type(&found_key) != BTRFS_INLINE_DATA_KEY)
1452 copy_size = btrfs_item_size(leaf->items + slot);
1453 if (found_key.offset + copy_size <= pos)
1455 dst = btrfs_item_ptr(leaf, path->slots[0], char);
1456 dst += pos - found_key.offset;
1457 copy_size = copy_size - (pos - found_key.offset);
1458 BUG_ON(copy_size < 0);
1459 copy_size = min(write_bytes, copy_size);
1460 WARN_ON(copy_size == 0);
1464 btrfs_release_path(root, path);
1465 copy_size = min(write_bytes,
1466 (size_t)BTRFS_LEAF_DATA_SIZE(root) -
1467 sizeof(struct btrfs_item) * 4);
1468 ret = btrfs_insert_empty_item(trans, root, path, &key, copy_size);
1470 dst = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
1471 path->slots[0], char);
1473 WARN_ON(copy_size == 0);
1474 WARN_ON(dst + copy_size >
1475 btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
1476 path->slots[0], char) +
1477 btrfs_item_size(btrfs_buffer_leaf(path->nodes[0])->items +
1479 btrfs_memcpy(root, path->nodes[0]->b_data, dst,
1480 page_address(page) + offset, copy_size);
1481 mark_buffer_dirty(path->nodes[0]);
1482 btrfs_release_path(root, path);
1484 offset += copy_size;
1485 num_written += copy_size;
1486 write_bytes -= copy_size;
1490 btrfs_free_path(path);
1491 ret = btrfs_end_transaction(trans, root);
1493 mutex_unlock(&root->fs_info->fs_mutex);
1494 return num_written ? num_written : err;
1497 static ssize_t btrfs_file_inline_write(struct file *file,
1498 const char __user *buf,
1499 size_t count, loff_t *ppos)
1502 size_t num_written = 0;
1505 struct inode *inode = file->f_path.dentry->d_inode;
1506 struct btrfs_root *root = BTRFS_I(inode)->root;
1507 unsigned long page_index;
1509 if (file->f_flags & O_DIRECT)
1513 vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
1514 current->backing_dev_info = inode->i_mapping->backing_dev_info;
1515 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
1520 err = remove_suid(file->f_path.dentry);
1523 file_update_time(file);
1524 mutex_lock(&inode->i_mutex);
1526 size_t offset = pos & (PAGE_CACHE_SIZE - 1);
1527 size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset);
1530 page_index = pos >> PAGE_CACHE_SHIFT;
1531 page = grab_cache_page(inode->i_mapping, page_index);
1532 if (!PageUptodate(page)) {
1533 ret = mpage_readpage(page, btrfs_get_block);
1537 ret = btrfs_copy_from_user(pos, 1,
1538 write_bytes, &page, buf);
1540 write_bytes = inline_one_page(root, inode, page, pos,
1541 offset, write_bytes);
1542 SetPageUptodate(page);
1543 if (write_bytes > 0 && pos + write_bytes > inode->i_size) {
1544 i_size_write(inode, pos + write_bytes);
1545 mark_inode_dirty(inode);
1547 page_cache_release(page);
1549 if (write_bytes < 0)
1552 count -= write_bytes;
1554 num_written += write_bytes;
1556 balance_dirty_pages_ratelimited(inode->i_mapping);
1560 mutex_unlock(&inode->i_mutex);
1563 current->backing_dev_info = NULL;
1564 return num_written ? num_written : err;
1568 static int btrfs_read_actor(read_descriptor_t *desc, struct page *page,
1569 unsigned long offset, unsigned long size)
1572 unsigned long left, count = desc->count;
1573 struct inode *inode = page->mapping->host;
1578 if (!PageChecked(page)) {
1579 /* FIXME, do it per block */
1580 struct btrfs_root *root = BTRFS_I(inode)->root;
1581 int ret = btrfs_csum_verify_file_block(root,
1582 page->mapping->host->i_ino,
1583 page->index << PAGE_CACHE_SHIFT,
1584 kmap(page), PAGE_CACHE_SIZE);
1586 printk("failed to verify ino %lu page %lu\n",
1587 page->mapping->host->i_ino,
1589 memset(page_address(page), 0, PAGE_CACHE_SIZE);
1591 SetPageChecked(page);
1595 * Faults on the destination of a read are common, so do it before
1598 if (!fault_in_pages_writeable(desc->arg.buf, size)) {
1599 kaddr = kmap_atomic(page, KM_USER0);
1600 left = __copy_to_user_inatomic(desc->arg.buf,
1601 kaddr + offset, size);
1602 kunmap_atomic(kaddr, KM_USER0);
1607 /* Do it the slow way */
1609 left = __copy_to_user(desc->arg.buf, kaddr + offset, size);
1614 desc->error = -EFAULT;
1617 desc->count = count - size;
1618 desc->written += size;
1619 desc->arg.buf += size;
1624 * btrfs_file_aio_read - filesystem read routine
1625 * @iocb: kernel I/O control block
1626 * @iov: io vector request
1627 * @nr_segs: number of segments in the iovec
1628 * @pos: current file position
1630 static ssize_t btrfs_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
1631 unsigned long nr_segs, loff_t pos)
1633 struct file *filp = iocb->ki_filp;
1637 loff_t *ppos = &iocb->ki_pos;
1640 for (seg = 0; seg < nr_segs; seg++) {
1641 const struct iovec *iv = &iov[seg];
1644 * If any segment has a negative length, or the cumulative
1645 * length ever wraps negative then return -EINVAL.
1647 count += iv->iov_len;
1648 if (unlikely((ssize_t)(count|iv->iov_len) < 0))
1650 if (access_ok(VERIFY_WRITE, iv->iov_base, iv->iov_len))
1655 count -= iv->iov_len; /* This segment is no good */
1660 for (seg = 0; seg < nr_segs; seg++) {
1661 read_descriptor_t desc;
1664 desc.arg.buf = iov[seg].iov_base;
1665 desc.count = iov[seg].iov_len;
1666 if (desc.count == 0)
1669 do_generic_file_read(filp, ppos, &desc,
1671 retval += desc.written;
1673 retval = retval ?: desc.error;
1681 static int create_subvol(struct btrfs_root *root, char *name, int namelen)
1683 struct btrfs_trans_handle *trans;
1684 struct btrfs_key key;
1685 struct btrfs_root_item root_item;
1686 struct btrfs_inode_item *inode_item;
1687 struct buffer_head *subvol;
1688 struct btrfs_leaf *leaf;
1689 struct btrfs_root *new_root;
1690 struct inode *inode;
1693 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
1695 mutex_lock(&root->fs_info->fs_mutex);
1696 trans = btrfs_start_transaction(root, 1);
1699 subvol = btrfs_alloc_free_block(trans, root);
1700 leaf = btrfs_buffer_leaf(subvol);
1701 btrfs_set_header_nritems(&leaf->header, 0);
1702 btrfs_set_header_level(&leaf->header, 0);
1703 btrfs_set_header_blocknr(&leaf->header, bh_blocknr(subvol));
1704 btrfs_set_header_generation(&leaf->header, trans->transid);
1705 memcpy(leaf->header.fsid, root->fs_info->disk_super->fsid,
1706 sizeof(leaf->header.fsid));
1708 inode_item = &root_item.inode;
1709 memset(inode_item, 0, sizeof(*inode_item));
1710 btrfs_set_inode_generation(inode_item, 1);
1711 btrfs_set_inode_size(inode_item, 3);
1712 btrfs_set_inode_nlink(inode_item, 1);
1713 btrfs_set_inode_nblocks(inode_item, 1);
1714 btrfs_set_inode_mode(inode_item, S_IFDIR | 0755);
1716 btrfs_set_root_blocknr(&root_item, bh_blocknr(subvol));
1717 btrfs_set_root_refs(&root_item, 1);
1719 mark_buffer_dirty(subvol);
1723 ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
1727 btrfs_set_root_dirid(&root_item, new_dirid);
1729 key.objectid = objectid;
1732 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
1733 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
1738 * insert the directory item
1740 key.offset = (u64)-1;
1741 ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
1743 root->fs_info->sb->s_root->d_inode->i_ino,
1747 ret = btrfs_commit_transaction(trans, root);
1750 new_root = btrfs_read_fs_root(root->fs_info, &key);
1753 trans = btrfs_start_transaction(new_root, 1);
1756 inode = btrfs_new_inode(trans, new_root, new_dirid, S_IFDIR | 0700);
1757 inode->i_op = &btrfs_dir_inode_operations;
1758 inode->i_fop = &btrfs_dir_file_operations;
1760 ret = btrfs_make_empty_dir(trans, new_root, new_dirid, new_dirid);
1765 ret = btrfs_update_inode(trans, new_root, inode);
1768 ret = btrfs_commit_transaction(trans, new_root);
1773 mutex_unlock(&root->fs_info->fs_mutex);
1777 static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
1779 struct btrfs_trans_handle *trans;
1780 struct btrfs_key key;
1781 struct btrfs_root_item new_root_item;
1785 if (!root->ref_cows)
1788 mutex_lock(&root->fs_info->fs_mutex);
1789 trans = btrfs_start_transaction(root, 1);
1792 ret = btrfs_update_inode(trans, root, root->inode);
1795 ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
1799 memcpy(&new_root_item, &root->root_item,
1800 sizeof(new_root_item));
1802 key.objectid = objectid;
1805 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
1806 btrfs_set_root_blocknr(&new_root_item, bh_blocknr(root->node));
1808 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
1812 printk("adding snapshot name %.*s root %Lu %Lu %u\n", namelen, name, key.objectid, key.offset, key.flags);
1815 * insert the directory item
1817 key.offset = (u64)-1;
1818 ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
1820 root->fs_info->sb->s_root->d_inode->i_ino,
1825 ret = btrfs_inc_root_ref(trans, root);
1828 ret = btrfs_commit_transaction(trans, root);
1830 mutex_unlock(&root->fs_info->fs_mutex);
1834 static int btrfs_ioctl(struct inode *inode, struct file *filp, unsigned int
1835 cmd, unsigned long arg)
1837 struct btrfs_root *root = BTRFS_I(inode)->root;
1838 struct btrfs_ioctl_vol_args vol_args;
1841 struct btrfs_path *path;
1845 case BTRFS_IOC_SNAP_CREATE:
1846 if (copy_from_user(&vol_args,
1847 (struct btrfs_ioctl_vol_args __user *)arg,
1850 namelen = strlen(vol_args.name);
1851 if (namelen > BTRFS_VOL_NAME_MAX)
1853 path = btrfs_alloc_path();
1856 root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
1857 mutex_lock(&root->fs_info->fs_mutex);
1858 ret = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
1860 vol_args.name, namelen, 0);
1861 mutex_unlock(&root->fs_info->fs_mutex);
1862 btrfs_free_path(path);
1866 if (root == root->fs_info->tree_root)
1867 ret = create_subvol(root, vol_args.name, namelen);
1869 ret = create_snapshot(root, vol_args.name, namelen);
1878 static struct kmem_cache *btrfs_inode_cachep;
1879 struct kmem_cache *btrfs_trans_handle_cachep;
1880 struct kmem_cache *btrfs_transaction_cachep;
1881 struct kmem_cache *btrfs_bit_radix_cachep;
1882 struct kmem_cache *btrfs_path_cachep;
1885 * Called inside transaction, so use GFP_NOFS
1887 static struct inode *btrfs_alloc_inode(struct super_block *sb)
1889 struct btrfs_inode *ei;
1891 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
1894 return &ei->vfs_inode;
1897 static void btrfs_destroy_inode(struct inode *inode)
1899 WARN_ON(!list_empty(&inode->i_dentry));
1900 WARN_ON(inode->i_data.nrpages);
1902 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
1905 static void init_once(void * foo, struct kmem_cache * cachep,
1906 unsigned long flags)
1908 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
1910 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
1911 SLAB_CTOR_CONSTRUCTOR) {
1912 inode_init_once(&ei->vfs_inode);
1916 static int init_inodecache(void)
1918 btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache",
1919 sizeof(struct btrfs_inode),
1920 0, (SLAB_RECLAIM_ACCOUNT|
1923 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache",
1924 sizeof(struct btrfs_trans_handle),
1925 0, (SLAB_RECLAIM_ACCOUNT|
1928 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache",
1929 sizeof(struct btrfs_transaction),
1930 0, (SLAB_RECLAIM_ACCOUNT|
1933 btrfs_path_cachep = kmem_cache_create("btrfs_path_cache",
1934 sizeof(struct btrfs_transaction),
1935 0, (SLAB_RECLAIM_ACCOUNT|
1938 btrfs_bit_radix_cachep = kmem_cache_create("btrfs_radix",
1940 0, (SLAB_RECLAIM_ACCOUNT|
1942 SLAB_DESTROY_BY_RCU),
1944 if (btrfs_inode_cachep == NULL || btrfs_trans_handle_cachep == NULL ||
1945 btrfs_transaction_cachep == NULL || btrfs_bit_radix_cachep == NULL)
1950 static void destroy_inodecache(void)
1952 kmem_cache_destroy(btrfs_inode_cachep);
1953 kmem_cache_destroy(btrfs_trans_handle_cachep);
1954 kmem_cache_destroy(btrfs_transaction_cachep);
1955 kmem_cache_destroy(btrfs_bit_radix_cachep);
1956 kmem_cache_destroy(btrfs_path_cachep);
1959 static int btrfs_get_sb(struct file_system_type *fs_type,
1960 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
1962 return get_sb_bdev(fs_type, flags, dev_name, data,
1963 btrfs_fill_super, mnt);
1966 static struct file_system_type btrfs_fs_type = {
1967 .owner = THIS_MODULE,
1969 .get_sb = btrfs_get_sb,
1970 .kill_sb = kill_block_super,
1971 .fs_flags = FS_REQUIRES_DEV,
1974 static struct super_operations btrfs_super_ops = {
1975 .statfs = simple_statfs,
1976 .delete_inode = btrfs_delete_inode,
1977 .put_super = btrfs_put_super,
1978 .read_inode = btrfs_read_locked_inode,
1979 .write_super = btrfs_write_super,
1980 .sync_fs = btrfs_sync_fs,
1981 .write_inode = btrfs_write_inode,
1982 .alloc_inode = btrfs_alloc_inode,
1983 .destroy_inode = btrfs_destroy_inode,
1986 static struct inode_operations btrfs_dir_inode_operations = {
1987 .lookup = btrfs_lookup,
1988 .create = btrfs_create,
1989 .unlink = btrfs_unlink,
1990 .mkdir = btrfs_mkdir,
1991 .rmdir = btrfs_rmdir,
1994 static struct inode_operations btrfs_dir_ro_inode_operations = {
1995 .lookup = btrfs_lookup,
1998 static struct file_operations btrfs_dir_file_operations = {
1999 .llseek = generic_file_llseek,
2000 .read = generic_read_dir,
2001 .readdir = btrfs_readdir,
2002 .ioctl = btrfs_ioctl,
2005 static struct address_space_operations btrfs_aops = {
2006 .readpage = btrfs_readpage,
2007 .readpages = btrfs_readpages,
2008 .writepage = btrfs_writepage,
2009 .sync_page = block_sync_page,
2010 .prepare_write = btrfs_prepare_write,
2011 .commit_write = btrfs_commit_write,
2014 static struct inode_operations btrfs_file_inode_operations = {
2015 .truncate = btrfs_truncate,
2018 static struct file_operations btrfs_file_operations = {
2019 .llseek = generic_file_llseek,
2020 .read = do_sync_read,
2021 .aio_read = btrfs_file_aio_read,
2022 .write = btrfs_file_write,
2023 .mmap = generic_file_mmap,
2024 .open = generic_file_open,
2025 .ioctl = btrfs_ioctl,
2028 static int __init init_btrfs_fs(void)
2031 printk("btrfs loaded!\n");
2032 err = init_inodecache();
2035 kset_set_kset_s(&btrfs_subsys, fs_subsys);
2036 err = subsystem_register(&btrfs_subsys);
2039 return register_filesystem(&btrfs_fs_type);
2041 destroy_inodecache();
2045 static void __exit exit_btrfs_fs(void)
2047 destroy_inodecache();
2048 unregister_filesystem(&btrfs_fs_type);
2049 subsystem_unregister(&btrfs_subsys);
2050 printk("btrfs unloaded\n");
2053 module_init(init_btrfs_fs)
2054 module_exit(exit_btrfs_fs)
2056 MODULE_LICENSE("GPL");