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>
14 #include <linux/statfs.h>
17 #include "transaction.h"
18 #include "btrfs_inode.h"
21 void btrfs_fsinfo_release(struct kobject *obj)
23 struct btrfs_fs_info *fsinfo = container_of(obj,
24 struct btrfs_fs_info, kobj);
28 struct kobj_type btrfs_fsinfo_ktype = {
29 .release = btrfs_fsinfo_release,
32 struct btrfs_iget_args {
34 struct btrfs_root *root;
37 decl_subsys(btrfs, &btrfs_fsinfo_ktype, NULL);
39 #define BTRFS_SUPER_MAGIC 0x9123682E
41 static struct inode_operations btrfs_dir_inode_operations;
42 static struct inode_operations btrfs_dir_ro_inode_operations;
43 static struct super_operations btrfs_super_ops;
44 static struct file_operations btrfs_dir_file_operations;
45 static struct inode_operations btrfs_file_inode_operations;
46 static struct address_space_operations btrfs_aops;
47 static struct file_operations btrfs_file_operations;
49 static void btrfs_read_locked_inode(struct inode *inode)
51 struct btrfs_path *path;
52 struct btrfs_inode_item *inode_item;
53 struct btrfs_root *root = BTRFS_I(inode)->root;
54 struct btrfs_key location;
57 path = btrfs_alloc_path();
59 btrfs_init_path(path);
60 mutex_lock(&root->fs_info->fs_mutex);
62 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
63 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
65 btrfs_free_path(path);
68 inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
70 struct btrfs_inode_item);
72 inode->i_mode = btrfs_inode_mode(inode_item);
73 inode->i_nlink = btrfs_inode_nlink(inode_item);
74 inode->i_uid = btrfs_inode_uid(inode_item);
75 inode->i_gid = btrfs_inode_gid(inode_item);
76 inode->i_size = btrfs_inode_size(inode_item);
77 inode->i_atime.tv_sec = btrfs_timespec_sec(&inode_item->atime);
78 inode->i_atime.tv_nsec = btrfs_timespec_nsec(&inode_item->atime);
79 inode->i_mtime.tv_sec = btrfs_timespec_sec(&inode_item->mtime);
80 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(&inode_item->mtime);
81 inode->i_ctime.tv_sec = btrfs_timespec_sec(&inode_item->ctime);
82 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(&inode_item->ctime);
83 inode->i_blocks = btrfs_inode_nblocks(inode_item);
84 inode->i_generation = btrfs_inode_generation(inode_item);
86 btrfs_free_path(path);
89 mutex_unlock(&root->fs_info->fs_mutex);
91 switch (inode->i_mode & S_IFMT) {
94 init_special_inode(inode, inode->i_mode,
95 btrfs_inode_rdev(inode_item));
99 inode->i_mapping->a_ops = &btrfs_aops;
100 inode->i_fop = &btrfs_file_operations;
101 inode->i_op = &btrfs_file_inode_operations;
104 inode->i_fop = &btrfs_dir_file_operations;
105 if (root == root->fs_info->tree_root)
106 inode->i_op = &btrfs_dir_ro_inode_operations;
108 inode->i_op = &btrfs_dir_inode_operations;
111 // inode->i_op = &page_symlink_inode_operations;
117 btrfs_release_path(root, path);
118 btrfs_free_path(path);
119 mutex_unlock(&root->fs_info->fs_mutex);
120 make_bad_inode(inode);
123 static void fill_inode_item(struct btrfs_inode_item *item,
126 btrfs_set_inode_uid(item, inode->i_uid);
127 btrfs_set_inode_gid(item, inode->i_gid);
128 btrfs_set_inode_size(item, inode->i_size);
129 btrfs_set_inode_mode(item, inode->i_mode);
130 btrfs_set_inode_nlink(item, inode->i_nlink);
131 btrfs_set_timespec_sec(&item->atime, inode->i_atime.tv_sec);
132 btrfs_set_timespec_nsec(&item->atime, inode->i_atime.tv_nsec);
133 btrfs_set_timespec_sec(&item->mtime, inode->i_mtime.tv_sec);
134 btrfs_set_timespec_nsec(&item->mtime, inode->i_mtime.tv_nsec);
135 btrfs_set_timespec_sec(&item->ctime, inode->i_ctime.tv_sec);
136 btrfs_set_timespec_nsec(&item->ctime, inode->i_ctime.tv_nsec);
137 btrfs_set_inode_nblocks(item, inode->i_blocks);
138 btrfs_set_inode_generation(item, inode->i_generation);
142 static int btrfs_update_inode(struct btrfs_trans_handle *trans,
143 struct btrfs_root *root,
146 struct btrfs_inode_item *inode_item;
147 struct btrfs_path *path;
150 path = btrfs_alloc_path();
152 btrfs_init_path(path);
153 ret = btrfs_lookup_inode(trans, root, path,
154 &BTRFS_I(inode)->location, 1);
161 inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
163 struct btrfs_inode_item);
165 fill_inode_item(inode_item, inode);
166 btrfs_mark_buffer_dirty(path->nodes[0]);
169 btrfs_release_path(root, path);
170 btrfs_free_path(path);
175 static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
176 struct btrfs_root *root,
178 struct dentry *dentry)
180 struct btrfs_path *path;
181 const char *name = dentry->d_name.name;
182 int name_len = dentry->d_name.len;
185 struct btrfs_dir_item *di;
187 path = btrfs_alloc_path();
189 btrfs_init_path(path);
190 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
200 objectid = btrfs_disk_key_objectid(&di->location);
201 ret = btrfs_delete_one_dir_name(trans, root, path, di);
203 btrfs_release_path(root, path);
205 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
206 objectid, name, name_len, -1);
215 ret = btrfs_delete_one_dir_name(trans, root, path, di);
218 dentry->d_inode->i_ctime = dir->i_ctime;
220 btrfs_free_path(path);
222 dir->i_size -= name_len * 2;
223 btrfs_update_inode(trans, root, dir);
224 drop_nlink(dentry->d_inode);
225 btrfs_update_inode(trans, root, dentry->d_inode);
230 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
232 struct btrfs_root *root;
233 struct btrfs_trans_handle *trans;
236 root = BTRFS_I(dir)->root;
237 mutex_lock(&root->fs_info->fs_mutex);
238 trans = btrfs_start_transaction(root, 1);
239 ret = btrfs_unlink_trans(trans, root, dir, dentry);
240 btrfs_end_transaction(trans, root);
241 mutex_unlock(&root->fs_info->fs_mutex);
245 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
247 struct inode *inode = dentry->d_inode;
250 struct btrfs_root *root = BTRFS_I(dir)->root;
251 struct btrfs_path *path;
252 struct btrfs_key key;
253 struct btrfs_trans_handle *trans;
254 struct btrfs_key found_key;
256 struct btrfs_leaf *leaf;
257 char *goodnames = "..";
259 path = btrfs_alloc_path();
261 btrfs_init_path(path);
262 mutex_lock(&root->fs_info->fs_mutex);
263 trans = btrfs_start_transaction(root, 1);
264 key.objectid = inode->i_ino;
265 key.offset = (u64)-1;
268 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
274 if (path->slots[0] == 0) {
279 leaf = btrfs_buffer_leaf(path->nodes[0]);
280 btrfs_disk_key_to_cpu(&found_key,
281 &leaf->items[path->slots[0]].key);
282 found_type = btrfs_key_type(&found_key);
283 if (found_key.objectid != inode->i_ino) {
287 if ((found_type != BTRFS_DIR_ITEM_KEY &&
288 found_type != BTRFS_DIR_INDEX_KEY) ||
289 (!btrfs_match_dir_item_name(root, path, goodnames, 2) &&
290 !btrfs_match_dir_item_name(root, path, goodnames, 1))) {
294 ret = btrfs_del_item(trans, root, path);
297 if (found_type == BTRFS_DIR_ITEM_KEY && found_key.offset == 1)
299 btrfs_release_path(root, path);
302 btrfs_release_path(root, path);
304 /* now the directory is empty */
305 err = btrfs_unlink_trans(trans, root, dir, dentry);
310 btrfs_release_path(root, path);
311 btrfs_free_path(path);
312 mutex_unlock(&root->fs_info->fs_mutex);
313 ret = btrfs_end_transaction(trans, root);
319 static int btrfs_free_inode(struct btrfs_trans_handle *trans,
320 struct btrfs_root *root,
323 struct btrfs_path *path;
328 path = btrfs_alloc_path();
330 btrfs_init_path(path);
331 ret = btrfs_lookup_inode(trans, root, path,
332 &BTRFS_I(inode)->location, -1);
334 ret = btrfs_del_item(trans, root, path);
336 btrfs_free_path(path);
340 static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
341 struct btrfs_root *root,
345 struct btrfs_path *path;
346 struct btrfs_key key;
347 struct btrfs_disk_key *found_key;
348 struct btrfs_leaf *leaf;
349 struct btrfs_file_extent_item *fi = NULL;
350 u64 extent_start = 0;
351 u64 extent_num_blocks = 0;
354 path = btrfs_alloc_path();
356 /* FIXME, add redo link to tree so we don't leak on crash */
357 key.objectid = inode->i_ino;
358 key.offset = (u64)-1;
361 * use BTRFS_CSUM_ITEM_KEY because it is larger than inline keys
364 btrfs_set_key_type(&key, BTRFS_CSUM_ITEM_KEY);
366 btrfs_init_path(path);
367 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
372 BUG_ON(path->slots[0] == 0);
375 leaf = btrfs_buffer_leaf(path->nodes[0]);
376 found_key = &leaf->items[path->slots[0]].key;
377 if (btrfs_disk_key_objectid(found_key) != inode->i_ino)
379 if (btrfs_disk_key_type(found_key) != BTRFS_CSUM_ITEM_KEY &&
380 btrfs_disk_key_type(found_key) != BTRFS_EXTENT_DATA_KEY)
382 if (btrfs_disk_key_offset(found_key) < inode->i_size)
385 if (btrfs_disk_key_type(found_key) == BTRFS_EXTENT_DATA_KEY) {
386 fi = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
388 struct btrfs_file_extent_item);
389 if (btrfs_file_extent_type(fi) !=
390 BTRFS_FILE_EXTENT_INLINE) {
392 btrfs_file_extent_disk_blocknr(fi);
394 btrfs_file_extent_disk_num_blocks(fi);
395 /* FIXME blocksize != 4096 */
397 btrfs_file_extent_num_blocks(fi) << 3;
401 ret = btrfs_del_item(trans, root, path);
403 btrfs_release_path(root, path);
405 ret = btrfs_free_extent(trans, root, extent_start,
406 extent_num_blocks, 0);
412 btrfs_release_path(root, path);
413 btrfs_free_path(path);
417 static void btrfs_delete_inode(struct inode *inode)
419 struct btrfs_trans_handle *trans;
420 struct btrfs_root *root = BTRFS_I(inode)->root;
423 truncate_inode_pages(&inode->i_data, 0);
424 if (is_bad_inode(inode)) {
428 mutex_lock(&root->fs_info->fs_mutex);
429 trans = btrfs_start_transaction(root, 1);
430 if (S_ISREG(inode->i_mode)) {
431 ret = btrfs_truncate_in_trans(trans, root, inode);
434 btrfs_free_inode(trans, root, inode);
435 btrfs_end_transaction(trans, root);
436 mutex_unlock(&root->fs_info->fs_mutex);
442 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
443 struct btrfs_key *location)
445 const char *name = dentry->d_name.name;
446 int namelen = dentry->d_name.len;
447 struct btrfs_dir_item *di;
448 struct btrfs_path *path;
449 struct btrfs_root *root = BTRFS_I(dir)->root;
452 path = btrfs_alloc_path();
454 btrfs_init_path(path);
455 di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
457 if (!di || IS_ERR(di)) {
458 location->objectid = 0;
462 btrfs_disk_key_to_cpu(location, &di->location);
464 btrfs_release_path(root, path);
465 btrfs_free_path(path);
469 int fixup_tree_root_location(struct btrfs_root *root,
470 struct btrfs_key *location,
471 struct btrfs_root **sub_root)
473 struct btrfs_path *path;
474 struct btrfs_root_item *ri;
476 if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
478 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
481 path = btrfs_alloc_path();
483 mutex_lock(&root->fs_info->fs_mutex);
485 *sub_root = btrfs_read_fs_root(root->fs_info, location);
486 if (IS_ERR(*sub_root))
487 return PTR_ERR(*sub_root);
489 ri = &(*sub_root)->root_item;
490 location->objectid = btrfs_root_dirid(ri);
492 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
493 location->offset = 0;
495 btrfs_free_path(path);
496 mutex_unlock(&root->fs_info->fs_mutex);
500 int btrfs_init_locked_inode(struct inode *inode, void *p)
502 struct btrfs_iget_args *args = p;
503 inode->i_ino = args->ino;
504 BTRFS_I(inode)->root = args->root;
508 int btrfs_find_actor(struct inode *inode, void *opaque)
510 struct btrfs_iget_args *args = opaque;
511 return (args->ino == inode->i_ino &&
512 args->root == BTRFS_I(inode)->root);
515 struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
516 struct btrfs_root *root)
519 struct btrfs_iget_args args;
523 inode = iget5_locked(s, objectid, btrfs_find_actor,
524 btrfs_init_locked_inode,
529 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
530 struct nameidata *nd)
532 struct inode * inode;
533 struct btrfs_inode *bi = BTRFS_I(dir);
534 struct btrfs_root *root = bi->root;
535 struct btrfs_root *sub_root = root;
536 struct btrfs_key location;
539 if (dentry->d_name.len > BTRFS_NAME_LEN)
540 return ERR_PTR(-ENAMETOOLONG);
541 mutex_lock(&root->fs_info->fs_mutex);
542 ret = btrfs_inode_by_name(dir, dentry, &location);
543 mutex_unlock(&root->fs_info->fs_mutex);
547 if (location.objectid) {
548 ret = fixup_tree_root_location(root, &location, &sub_root);
552 return ERR_PTR(-ENOENT);
553 inode = btrfs_iget_locked(dir->i_sb, location.objectid,
556 return ERR_PTR(-EACCES);
557 if (inode->i_state & I_NEW) {
558 if (sub_root != root) {
559 printk("adding new root for inode %lu root %p (found %p)\n", inode->i_ino, sub_root, BTRFS_I(inode)->root);
561 sub_root->inode = inode;
563 BTRFS_I(inode)->root = sub_root;
564 memcpy(&BTRFS_I(inode)->location, &location,
566 btrfs_read_locked_inode(inode);
567 unlock_new_inode(inode);
570 return d_splice_alias(inode, dentry);
573 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
575 struct inode *inode = filp->f_path.dentry->d_inode;
576 struct btrfs_root *root = BTRFS_I(inode)->root;
577 struct btrfs_item *item;
578 struct btrfs_dir_item *di;
579 struct btrfs_key key;
580 struct btrfs_path *path;
583 struct btrfs_leaf *leaf;
586 unsigned char d_type = DT_UNKNOWN;
591 int key_type = BTRFS_DIR_INDEX_KEY;
593 /* FIXME, use a real flag for deciding about the key type */
594 if (root->fs_info->tree_root == root)
595 key_type = BTRFS_DIR_ITEM_KEY;
596 mutex_lock(&root->fs_info->fs_mutex);
597 key.objectid = inode->i_ino;
599 btrfs_set_key_type(&key, key_type);
600 key.offset = filp->f_pos;
601 path = btrfs_alloc_path();
602 btrfs_init_path(path);
603 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
608 leaf = btrfs_buffer_leaf(path->nodes[0]);
609 nritems = btrfs_header_nritems(&leaf->header);
610 slot = path->slots[0];
611 if (advance || slot >= nritems) {
612 if (slot >= nritems -1) {
613 ret = btrfs_next_leaf(root, path);
616 leaf = btrfs_buffer_leaf(path->nodes[0]);
617 nritems = btrfs_header_nritems(&leaf->header);
618 slot = path->slots[0];
625 item = leaf->items + slot;
626 if (btrfs_disk_key_objectid(&item->key) != key.objectid)
628 if (btrfs_disk_key_type(&item->key) != key_type)
630 if (btrfs_disk_key_offset(&item->key) < filp->f_pos)
632 filp->f_pos = btrfs_disk_key_offset(&item->key);
634 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
636 di_total = btrfs_item_size(leaf->items + slot);
637 while(di_cur < di_total) {
638 over = filldir(dirent, (const char *)(di + 1),
639 btrfs_dir_name_len(di),
640 btrfs_disk_key_offset(&item->key),
641 btrfs_disk_key_objectid(&di->location),
645 di_len = btrfs_dir_name_len(di) + sizeof(*di);
647 di = (struct btrfs_dir_item *)((char *)di + di_len);
654 btrfs_release_path(root, path);
655 btrfs_free_path(path);
656 mutex_unlock(&root->fs_info->fs_mutex);
660 static void btrfs_put_super (struct super_block * sb)
662 struct btrfs_root *root = btrfs_sb(sb);
665 ret = close_ctree(root);
667 printk("close ctree returns %d\n", ret);
669 sb->s_fs_info = NULL;
672 static int btrfs_fill_super(struct super_block * sb, void * data, int silent)
674 struct inode * inode;
675 struct dentry * root_dentry;
676 struct btrfs_super_block *disk_super;
677 struct btrfs_root *tree_root;
678 struct btrfs_inode *bi;
680 sb->s_maxbytes = MAX_LFS_FILESIZE;
681 sb->s_magic = BTRFS_SUPER_MAGIC;
682 sb->s_op = &btrfs_super_ops;
685 tree_root = open_ctree(sb);
688 printk("btrfs: open_ctree failed\n");
691 sb->s_fs_info = tree_root;
692 disk_super = tree_root->fs_info->disk_super;
693 printk("read in super total blocks %Lu root %Lu\n",
694 btrfs_super_total_blocks(disk_super),
695 btrfs_super_root_dir(disk_super));
697 inode = btrfs_iget_locked(sb, btrfs_super_root_dir(disk_super),
700 bi->location.objectid = inode->i_ino;
701 bi->location.offset = 0;
702 bi->location.flags = 0;
703 bi->root = tree_root;
704 btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY);
708 if (inode->i_state & I_NEW) {
709 btrfs_read_locked_inode(inode);
710 unlock_new_inode(inode);
713 root_dentry = d_alloc_root(inode);
718 sb->s_root = root_dentry;
723 static int btrfs_write_inode(struct inode *inode, int wait)
725 struct btrfs_root *root = BTRFS_I(inode)->root;
726 struct btrfs_trans_handle *trans;
730 mutex_lock(&root->fs_info->fs_mutex);
731 trans = btrfs_start_transaction(root, 1);
732 ret = btrfs_commit_transaction(trans, root);
733 mutex_unlock(&root->fs_info->fs_mutex);
738 static void btrfs_dirty_inode(struct inode *inode)
740 struct btrfs_root *root = BTRFS_I(inode)->root;
741 struct btrfs_trans_handle *trans;
743 mutex_lock(&root->fs_info->fs_mutex);
744 trans = btrfs_start_transaction(root, 1);
745 btrfs_update_inode(trans, root, inode);
746 btrfs_end_transaction(trans, root);
747 mutex_unlock(&root->fs_info->fs_mutex);
750 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
751 struct btrfs_root *root,
752 u64 objectid, int mode)
755 struct btrfs_inode_item inode_item;
756 struct btrfs_key *location;
759 inode = new_inode(root->fs_info->sb);
761 return ERR_PTR(-ENOMEM);
763 BTRFS_I(inode)->root = root;
765 inode->i_uid = current->fsuid;
766 inode->i_gid = current->fsgid;
767 inode->i_mode = mode;
768 inode->i_ino = objectid;
770 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
771 fill_inode_item(&inode_item, inode);
772 location = &BTRFS_I(inode)->location;
773 location->objectid = objectid;
775 location->offset = 0;
776 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
778 ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
781 insert_inode_hash(inode);
785 static int btrfs_add_link(struct btrfs_trans_handle *trans,
786 struct dentry *dentry, struct inode *inode)
789 struct btrfs_key key;
790 struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
791 key.objectid = inode->i_ino;
793 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
796 ret = btrfs_insert_dir_item(trans, root,
797 dentry->d_name.name, dentry->d_name.len,
798 dentry->d_parent->d_inode->i_ino,
801 dentry->d_parent->d_inode->i_size += dentry->d_name.len * 2;
802 ret = btrfs_update_inode(trans, root,
803 dentry->d_parent->d_inode);
808 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
809 struct dentry *dentry, struct inode *inode)
811 int err = btrfs_add_link(trans, dentry, inode);
813 d_instantiate(dentry, inode);
821 static int btrfs_create(struct inode *dir, struct dentry *dentry,
822 int mode, struct nameidata *nd)
824 struct btrfs_trans_handle *trans;
825 struct btrfs_root *root = BTRFS_I(dir)->root;
831 mutex_lock(&root->fs_info->fs_mutex);
832 trans = btrfs_start_transaction(root, 1);
834 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
840 inode = btrfs_new_inode(trans, root, objectid, mode);
841 err = PTR_ERR(inode);
844 // FIXME mark the inode dirty
845 err = btrfs_add_nondir(trans, dentry, inode);
849 inode->i_mapping->a_ops = &btrfs_aops;
850 inode->i_fop = &btrfs_file_operations;
851 inode->i_op = &btrfs_file_inode_operations;
853 dir->i_sb->s_dirt = 1;
855 btrfs_end_transaction(trans, root);
856 mutex_unlock(&root->fs_info->fs_mutex);
859 inode_dec_link_count(inode);
865 static int btrfs_make_empty_dir(struct btrfs_trans_handle *trans,
866 struct btrfs_root *root,
867 u64 objectid, u64 dirid)
871 struct btrfs_key key;
876 key.objectid = objectid;
879 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
881 ret = btrfs_insert_dir_item(trans, root, buf, 1, objectid,
885 key.objectid = dirid;
886 ret = btrfs_insert_dir_item(trans, root, buf, 2, objectid,
894 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
897 struct btrfs_trans_handle *trans;
898 struct btrfs_root *root = BTRFS_I(dir)->root;
903 mutex_lock(&root->fs_info->fs_mutex);
904 trans = btrfs_start_transaction(root, 1);
906 err = PTR_ERR(trans);
910 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
916 inode = btrfs_new_inode(trans, root, objectid, S_IFDIR | mode);
918 err = PTR_ERR(inode);
922 inode->i_op = &btrfs_dir_inode_operations;
923 inode->i_fop = &btrfs_dir_file_operations;
925 err = btrfs_make_empty_dir(trans, root, inode->i_ino, dir->i_ino);
930 err = btrfs_update_inode(trans, root, inode);
933 err = btrfs_add_link(trans, dentry, inode);
936 d_instantiate(dentry, inode);
940 btrfs_end_transaction(trans, root);
942 mutex_unlock(&root->fs_info->fs_mutex);
948 static int btrfs_sync_file(struct file *file,
949 struct dentry *dentry, int datasync)
951 struct inode *inode = dentry->d_inode;
952 struct btrfs_root *root = BTRFS_I(inode)->root;
954 struct btrfs_trans_handle *trans;
956 mutex_lock(&root->fs_info->fs_mutex);
957 trans = btrfs_start_transaction(root, 1);
962 ret = btrfs_commit_transaction(trans, root);
963 mutex_unlock(&root->fs_info->fs_mutex);
965 return ret > 0 ? EIO : ret;
968 static int btrfs_sync_fs(struct super_block *sb, int wait)
970 struct btrfs_trans_handle *trans;
971 struct btrfs_root *root;
977 filemap_flush(root->fs_info->btree_inode->i_mapping);
980 filemap_write_and_wait(root->fs_info->btree_inode->i_mapping);
981 mutex_lock(&root->fs_info->fs_mutex);
982 trans = btrfs_start_transaction(root, 1);
983 ret = btrfs_commit_transaction(trans, root);
986 printk("btrfs sync_fs\n");
987 mutex_unlock(&root->fs_info->fs_mutex);
991 static int btrfs_get_block_lock(struct inode *inode, sector_t iblock,
992 struct buffer_head *result, int create)
997 u64 extent_start = 0;
999 u64 objectid = inode->i_ino;
1001 struct btrfs_path *path;
1002 struct btrfs_root *root = BTRFS_I(inode)->root;
1003 struct btrfs_file_extent_item *item;
1004 struct btrfs_leaf *leaf;
1005 struct btrfs_disk_key *found_key;
1007 path = btrfs_alloc_path();
1009 btrfs_init_path(path);
1014 ret = btrfs_lookup_file_extent(NULL, root, path,
1016 iblock << inode->i_blkbits, 0);
1023 if (path->slots[0] == 0) {
1024 btrfs_release_path(root, path);
1030 item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
1031 struct btrfs_file_extent_item);
1032 leaf = btrfs_buffer_leaf(path->nodes[0]);
1033 blocknr = btrfs_file_extent_disk_blocknr(item);
1034 blocknr += btrfs_file_extent_offset(item);
1036 /* are we inside the extent that was found? */
1037 found_key = &leaf->items[path->slots[0]].key;
1038 found_type = btrfs_disk_key_type(found_key);
1039 if (btrfs_disk_key_objectid(found_key) != objectid ||
1040 found_type != BTRFS_EXTENT_DATA_KEY) {
1043 btrfs_release_path(root, path);
1046 found_type = btrfs_file_extent_type(item);
1047 extent_start = btrfs_disk_key_offset(&leaf->items[path->slots[0]].key);
1048 if (found_type == BTRFS_FILE_EXTENT_REG) {
1049 extent_start = extent_start >> inode->i_blkbits;
1050 extent_end = extent_start + btrfs_file_extent_num_blocks(item);
1051 if (iblock >= extent_start && iblock < extent_end) {
1053 btrfs_map_bh_to_logical(root, result, blocknr +
1054 iblock - extent_start);
1057 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
1061 size = btrfs_file_extent_inline_len(leaf->items +
1063 extent_end = (extent_start + size) >> inode->i_blkbits;
1064 extent_start >>= inode->i_blkbits;
1065 if (iblock < extent_start || iblock > extent_end) {
1068 ptr = btrfs_file_extent_inline_start(item);
1069 map = kmap(result->b_page);
1070 memcpy(map, ptr, size);
1071 memset(map + size, 0, PAGE_CACHE_SIZE - size);
1072 flush_dcache_page(result->b_page);
1073 kunmap(result->b_page);
1074 set_buffer_uptodate(result);
1075 SetPageChecked(result->b_page);
1076 btrfs_map_bh_to_logical(root, result, 0);
1079 btrfs_release_path(root, path);
1080 btrfs_free_path(path);
1084 static int btrfs_get_block(struct inode *inode, sector_t iblock,
1085 struct buffer_head *result, int create)
1088 struct btrfs_root *root = BTRFS_I(inode)->root;
1089 mutex_lock(&root->fs_info->fs_mutex);
1090 err = btrfs_get_block_lock(inode, iblock, result, create);
1091 mutex_unlock(&root->fs_info->fs_mutex);
1095 static int btrfs_prepare_write(struct file *file, struct page *page,
1096 unsigned from, unsigned to)
1098 return nobh_prepare_write(page, from, to, btrfs_get_block);
1101 static void btrfs_write_super(struct super_block *sb)
1103 btrfs_sync_fs(sb, 1);
1106 static int btrfs_readpage(struct file *file, struct page *page)
1108 return mpage_readpage(page, btrfs_get_block);
1112 * While block_write_full_page is writing back the dirty buffers under
1113 * the page lock, whoever dirtied the buffers may decide to clean them
1114 * again at any time. We handle that by only looking at the buffer
1115 * state inside lock_buffer().
1117 * If block_write_full_page() is called for regular writeback
1118 * (wbc->sync_mode == WB_SYNC_NONE) then it will redirty a page which has a
1119 * locked buffer. This only can happen if someone has written the buffer
1120 * directly, with submit_bh(). At the address_space level PageWriteback
1121 * prevents this contention from occurring.
1123 static int __btrfs_write_full_page(struct inode *inode, struct page *page,
1124 struct writeback_control *wbc)
1128 sector_t last_block;
1129 struct buffer_head *bh, *head;
1130 const unsigned blocksize = 1 << inode->i_blkbits;
1131 int nr_underway = 0;
1133 BUG_ON(!PageLocked(page));
1135 last_block = (i_size_read(inode) - 1) >> inode->i_blkbits;
1137 if (!page_has_buffers(page)) {
1138 create_empty_buffers(page, blocksize,
1139 (1 << BH_Dirty)|(1 << BH_Uptodate));
1143 * Be very careful. We have no exclusion from __set_page_dirty_buffers
1144 * here, and the (potentially unmapped) buffers may become dirty at
1145 * any time. If a buffer becomes dirty here after we've inspected it
1146 * then we just miss that fact, and the page stays dirty.
1148 * Buffers outside i_size may be dirtied by __set_page_dirty_buffers;
1149 * handle that here by just cleaning them.
1152 block = (sector_t)page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
1153 head = page_buffers(page);
1157 * Get all the dirty buffers mapped to disk addresses and
1158 * handle any aliases from the underlying blockdev's mapping.
1161 if (block > last_block) {
1163 * mapped buffers outside i_size will occur, because
1164 * this page can be outside i_size when there is a
1165 * truncate in progress.
1168 * The buffer was zeroed by block_write_full_page()
1170 clear_buffer_dirty(bh);
1171 set_buffer_uptodate(bh);
1172 } else if (!buffer_mapped(bh) && buffer_dirty(bh)) {
1173 WARN_ON(bh->b_size != blocksize);
1174 err = btrfs_get_block(inode, block, bh, 0);
1177 if (buffer_new(bh)) {
1178 /* blockdev mappings never come here */
1179 clear_buffer_new(bh);
1180 unmap_underlying_metadata(bh->b_bdev,
1184 bh = bh->b_this_page;
1186 } while (bh != head);
1189 if (!buffer_mapped(bh))
1192 * If it's a fully non-blocking write attempt and we cannot
1193 * lock the buffer then redirty the page. Note that this can
1194 * potentially cause a busy-wait loop from pdflush and kswapd
1195 * activity, but those code paths have their own higher-level
1198 if (wbc->sync_mode != WB_SYNC_NONE || !wbc->nonblocking) {
1200 } else if (test_set_buffer_locked(bh)) {
1201 redirty_page_for_writepage(wbc, page);
1204 if (test_clear_buffer_dirty(bh) && bh->b_blocknr != 0) {
1205 mark_buffer_async_write(bh);
1209 } while ((bh = bh->b_this_page) != head);
1212 * The page and its buffers are protected by PageWriteback(), so we can
1213 * drop the bh refcounts early.
1215 BUG_ON(PageWriteback(page));
1216 set_page_writeback(page);
1219 struct buffer_head *next = bh->b_this_page;
1220 if (buffer_async_write(bh)) {
1221 submit_bh(WRITE, bh);
1225 } while (bh != head);
1230 if (nr_underway == 0) {
1232 * The page was marked dirty, but the buffers were
1233 * clean. Someone wrote them back by hand with
1234 * ll_rw_block/submit_bh. A rare case.
1238 if (!buffer_uptodate(bh)) {
1242 bh = bh->b_this_page;
1243 } while (bh != head);
1245 SetPageUptodate(page);
1246 end_page_writeback(page);
1248 * The page and buffer_heads can be released at any time from
1251 wbc->pages_skipped++; /* We didn't write this page */
1257 * ENOSPC, or some other error. We may already have added some
1258 * blocks to the file, so we need to write these out to avoid
1259 * exposing stale data.
1260 * The page is currently locked and not marked for writeback
1263 /* Recovery: lock and submit the mapped buffers */
1265 if (buffer_mapped(bh) && buffer_dirty(bh)) {
1267 mark_buffer_async_write(bh);
1270 * The buffer may have been set dirty during
1271 * attachment to a dirty page.
1273 clear_buffer_dirty(bh);
1275 } while ((bh = bh->b_this_page) != head);
1277 BUG_ON(PageWriteback(page));
1278 set_page_writeback(page);
1280 struct buffer_head *next = bh->b_this_page;
1281 if (buffer_async_write(bh)) {
1282 clear_buffer_dirty(bh);
1283 submit_bh(WRITE, bh);
1287 } while (bh != head);
1293 * The generic ->writepage function for buffer-backed address_spaces
1295 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
1297 struct inode * const inode = page->mapping->host;
1298 loff_t i_size = i_size_read(inode);
1299 const pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
1303 /* Is the page fully inside i_size? */
1304 if (page->index < end_index)
1305 return __btrfs_write_full_page(inode, page, wbc);
1307 /* Is the page fully outside i_size? (truncate in progress) */
1308 offset = i_size & (PAGE_CACHE_SIZE-1);
1309 if (page->index >= end_index+1 || !offset) {
1311 * The page may have dirty, unmapped buffers. For example,
1312 * they may have been added in ext3_writepage(). Make them
1313 * freeable here, so the page does not leak.
1315 block_invalidatepage(page, 0);
1317 return 0; /* don't care */
1321 * The page straddles i_size. It must be zeroed out on each and every
1322 * writepage invokation because it may be mmapped. "A file is mapped
1323 * in multiples of the page size. For a file that is not a multiple of
1324 * the page size, the remaining memory is zeroed when mapped, and
1325 * writes to that region are not written out to the file."
1327 kaddr = kmap_atomic(page, KM_USER0);
1328 memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
1329 flush_dcache_page(page);
1330 kunmap_atomic(kaddr, KM_USER0);
1331 return __btrfs_write_full_page(inode, page, wbc);
1334 static void btrfs_truncate(struct inode *inode)
1336 struct btrfs_root *root = BTRFS_I(inode)->root;
1338 struct btrfs_trans_handle *trans;
1340 if (!S_ISREG(inode->i_mode))
1342 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
1345 nobh_truncate_page(inode->i_mapping, inode->i_size);
1347 /* FIXME, add redo link to tree so we don't leak on crash */
1348 mutex_lock(&root->fs_info->fs_mutex);
1349 trans = btrfs_start_transaction(root, 1);
1350 ret = btrfs_truncate_in_trans(trans, root, inode);
1352 ret = btrfs_end_transaction(trans, root);
1354 mutex_unlock(&root->fs_info->fs_mutex);
1355 mark_inode_dirty(inode);
1359 * Make sure any changes to nobh_commit_write() are reflected in
1360 * nobh_truncate_page(), since it doesn't call commit_write().
1362 static int btrfs_commit_write(struct file *file, struct page *page,
1363 unsigned from, unsigned to)
1365 struct inode *inode = page->mapping->host;
1366 struct buffer_head *bh;
1367 loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
1369 SetPageUptodate(page);
1370 bh = page_buffers(page);
1371 if (buffer_mapped(bh) && bh->b_blocknr != 0) {
1372 set_page_dirty(page);
1374 if (pos > inode->i_size) {
1375 i_size_write(inode, pos);
1376 mark_inode_dirty(inode);
1381 static int btrfs_copy_from_user(loff_t pos, int num_pages, int write_bytes,
1382 struct page **prepared_pages,
1383 const char __user * buf)
1385 long page_fault = 0;
1387 int offset = pos & (PAGE_CACHE_SIZE - 1);
1389 for (i = 0; i < num_pages && write_bytes > 0; i++, offset = 0) {
1390 size_t count = min_t(size_t,
1391 PAGE_CACHE_SIZE - offset, write_bytes);
1392 struct page *page = prepared_pages[i];
1393 fault_in_pages_readable(buf, count);
1395 /* Copy data from userspace to the current page */
1397 page_fault = __copy_from_user(page_address(page) + offset,
1399 /* Flush processor's dcache for this page */
1400 flush_dcache_page(page);
1403 write_bytes -= count;
1408 return page_fault ? -EFAULT : 0;
1411 static void btrfs_drop_pages(struct page **pages, size_t num_pages)
1414 for (i = 0; i < num_pages; i++) {
1417 unlock_page(pages[i]);
1418 mark_page_accessed(pages[i]);
1419 page_cache_release(pages[i]);
1422 static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
1423 struct btrfs_root *root,
1425 struct page **pages,
1435 struct inode *inode = file->f_path.dentry->d_inode;
1436 struct buffer_head *bh;
1437 struct btrfs_file_extent_item *ei;
1439 for (i = 0; i < num_pages; i++) {
1440 offset = pos & (PAGE_CACHE_SIZE -1);
1441 this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
1442 /* FIXME, one block at a time */
1444 mutex_lock(&root->fs_info->fs_mutex);
1445 trans = btrfs_start_transaction(root, 1);
1447 bh = page_buffers(pages[i]);
1448 if (buffer_mapped(bh) && bh->b_blocknr == 0) {
1449 struct btrfs_key key;
1450 struct btrfs_path *path;
1454 path = btrfs_alloc_path();
1456 key.objectid = inode->i_ino;
1457 key.offset = pages[i]->index << PAGE_CACHE_SHIFT;
1459 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
1460 BUG_ON(write_bytes >= PAGE_CACHE_SIZE);
1462 btrfs_file_extent_calc_inline_size(write_bytes);
1463 ret = btrfs_insert_empty_item(trans, root, path, &key,
1466 ei = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
1467 path->slots[0], struct btrfs_file_extent_item);
1468 btrfs_set_file_extent_generation(ei, trans->transid);
1469 btrfs_set_file_extent_type(ei,
1470 BTRFS_FILE_EXTENT_INLINE);
1471 ptr = btrfs_file_extent_inline_start(ei);
1472 memcpy(ptr, bh->b_data, offset + write_bytes);
1473 mark_buffer_dirty(path->nodes[0]);
1474 btrfs_free_path(path);
1476 btrfs_csum_file_block(trans, root, inode->i_ino,
1477 pages[i]->index << PAGE_CACHE_SHIFT,
1478 kmap(pages[i]), PAGE_CACHE_SIZE);
1481 SetPageChecked(pages[i]);
1482 ret = btrfs_end_transaction(trans, root);
1484 mutex_unlock(&root->fs_info->fs_mutex);
1486 ret = btrfs_commit_write(file, pages[i], offset,
1487 offset + this_write);
1493 WARN_ON(this_write > write_bytes);
1494 write_bytes -= this_write;
1500 static int drop_extents(struct btrfs_trans_handle *trans,
1501 struct btrfs_root *root,
1502 struct inode *inode,
1506 struct btrfs_key key;
1507 struct btrfs_leaf *leaf;
1509 struct btrfs_file_extent_item *extent;
1512 struct btrfs_file_extent_item old;
1513 struct btrfs_path *path;
1514 u64 search_start = start;
1520 path = btrfs_alloc_path();
1524 btrfs_release_path(root, path);
1525 ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
1530 if (path->slots[0] == 0) {
1541 leaf = btrfs_buffer_leaf(path->nodes[0]);
1542 slot = path->slots[0];
1543 btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
1544 if (key.offset >= end || key.objectid != inode->i_ino) {
1548 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) {
1552 extent = btrfs_item_ptr(leaf, slot,
1553 struct btrfs_file_extent_item);
1554 found_type = btrfs_file_extent_type(extent);
1555 if (found_type == BTRFS_FILE_EXTENT_REG) {
1556 extent_end = key.offset +
1557 (btrfs_file_extent_num_blocks(extent) <<
1560 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
1562 extent_end = key.offset +
1563 btrfs_file_extent_inline_len(leaf->items + slot);
1566 if (!found_extent && !found_inline) {
1571 if (search_start >= extent_end) {
1576 search_start = extent_end;
1578 if (end < extent_end && end >= key.offset) {
1580 memcpy(&old, extent, sizeof(old));
1581 ret = btrfs_inc_extent_ref(trans, root,
1582 btrfs_file_extent_disk_blocknr(&old),
1583 btrfs_file_extent_disk_num_blocks(&old));
1586 WARN_ON(found_inline);
1590 if (start > key.offset) {
1593 /* truncate existing extent */
1595 WARN_ON(start & (root->blocksize - 1));
1597 new_num = (start - key.offset) >>
1599 old_num = btrfs_file_extent_num_blocks(extent);
1600 inode->i_blocks -= (old_num - new_num) << 3;
1601 btrfs_set_file_extent_num_blocks(extent,
1603 mark_buffer_dirty(path->nodes[0]);
1607 ret = btrfs_truncate_item(trans, root, path,
1608 start - key.offset);
1614 u64 disk_blocknr = 0;
1615 u64 disk_num_blocks = 0;
1616 u64 extent_num_blocks = 0;
1619 btrfs_file_extent_disk_blocknr(extent);
1621 btrfs_file_extent_disk_num_blocks(extent);
1623 btrfs_file_extent_num_blocks(extent);
1625 ret = btrfs_del_item(trans, root, path);
1627 btrfs_release_path(root, path);
1630 btrfs_file_extent_num_blocks(extent) << 3;
1631 ret = btrfs_free_extent(trans, root,
1633 disk_num_blocks, 0);
1637 if (!bookend && search_start >= end) {
1644 if (bookend && found_extent) {
1645 /* create bookend */
1646 struct btrfs_key ins;
1647 ins.objectid = inode->i_ino;
1650 btrfs_set_key_type(&ins, BTRFS_EXTENT_DATA_KEY);
1652 btrfs_release_path(root, path);
1653 ret = btrfs_insert_empty_item(trans, root, path, &ins,
1656 extent = btrfs_item_ptr(
1657 btrfs_buffer_leaf(path->nodes[0]),
1659 struct btrfs_file_extent_item);
1660 btrfs_set_file_extent_disk_blocknr(extent,
1661 btrfs_file_extent_disk_blocknr(&old));
1662 btrfs_set_file_extent_disk_num_blocks(extent,
1663 btrfs_file_extent_disk_num_blocks(&old));
1665 btrfs_set_file_extent_offset(extent,
1666 btrfs_file_extent_offset(&old) +
1667 ((end - key.offset) >> inode->i_blkbits));
1668 WARN_ON(btrfs_file_extent_num_blocks(&old) <
1669 (end - key.offset) >> inode->i_blkbits);
1670 btrfs_set_file_extent_num_blocks(extent,
1671 btrfs_file_extent_num_blocks(&old) -
1672 ((end - key.offset) >> inode->i_blkbits));
1674 btrfs_set_file_extent_type(extent,
1675 BTRFS_FILE_EXTENT_REG);
1676 btrfs_set_file_extent_generation(extent,
1677 btrfs_file_extent_generation(&old));
1678 btrfs_mark_buffer_dirty(path->nodes[0]);
1680 btrfs_file_extent_num_blocks(extent) << 3;
1686 btrfs_free_path(path);
1690 static int prepare_pages(struct btrfs_root *root,
1692 struct page **pages,
1695 unsigned long first_index,
1696 unsigned long last_index,
1698 u64 alloc_extent_start)
1701 unsigned long index = pos >> PAGE_CACHE_SHIFT;
1702 struct inode *inode = file->f_path.dentry->d_inode;
1706 struct buffer_head *bh;
1707 struct buffer_head *head;
1708 loff_t isize = i_size_read(inode);
1710 memset(pages, 0, num_pages * sizeof(struct page *));
1712 for (i = 0; i < num_pages; i++) {
1713 pages[i] = grab_cache_page(inode->i_mapping, index + i);
1716 goto failed_release;
1718 offset = pos & (PAGE_CACHE_SIZE -1);
1719 this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
1720 create_empty_buffers(pages[i], root->fs_info->sb->s_blocksize,
1721 (1 << BH_Uptodate));
1722 head = page_buffers(pages[i]);
1725 err = btrfs_map_bh_to_logical(root, bh,
1726 alloc_extent_start);
1729 goto failed_truncate;
1730 bh = bh->b_this_page;
1731 if (alloc_extent_start)
1732 alloc_extent_start++;
1733 } while (bh != head);
1735 WARN_ON(this_write > write_bytes);
1736 write_bytes -= this_write;
1741 btrfs_drop_pages(pages, num_pages);
1745 btrfs_drop_pages(pages, num_pages);
1747 vmtruncate(inode, isize);
1751 static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
1752 size_t count, loff_t *ppos)
1755 size_t num_written = 0;
1758 struct inode *inode = file->f_path.dentry->d_inode;
1759 struct btrfs_root *root = BTRFS_I(inode)->root;
1760 struct page *pages[8];
1761 struct page *pinned[2] = { NULL, NULL };
1762 unsigned long first_index;
1763 unsigned long last_index;
1766 u64 alloc_extent_start;
1767 struct btrfs_trans_handle *trans;
1768 struct btrfs_key ins;
1770 if (file->f_flags & O_DIRECT)
1773 vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
1774 current->backing_dev_info = inode->i_mapping->backing_dev_info;
1775 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
1780 err = remove_suid(file->f_path.dentry);
1783 file_update_time(file);
1785 start_pos = pos & ~((u64)PAGE_CACHE_SIZE - 1);
1786 num_blocks = (count + pos - start_pos + root->blocksize - 1) >>
1789 mutex_lock(&inode->i_mutex);
1790 first_index = pos >> PAGE_CACHE_SHIFT;
1791 last_index = (pos + count) >> PAGE_CACHE_SHIFT;
1793 if ((first_index << PAGE_CACHE_SHIFT) < inode->i_size &&
1794 (pos & (PAGE_CACHE_SIZE - 1))) {
1795 pinned[0] = grab_cache_page(inode->i_mapping, first_index);
1796 if (!PageUptodate(pinned[0])) {
1797 ret = mpage_readpage(pinned[0], btrfs_get_block);
1800 unlock_page(pinned[0]);
1803 if (first_index != last_index &&
1804 (last_index << PAGE_CACHE_SHIFT) < inode->i_size &&
1805 (count & (PAGE_CACHE_SIZE - 1))) {
1806 pinned[1] = grab_cache_page(inode->i_mapping, last_index);
1807 if (!PageUptodate(pinned[1])) {
1808 ret = mpage_readpage(pinned[1], btrfs_get_block);
1811 unlock_page(pinned[1]);
1815 mutex_lock(&root->fs_info->fs_mutex);
1816 trans = btrfs_start_transaction(root, 1);
1819 mutex_unlock(&root->fs_info->fs_mutex);
1822 /* FIXME blocksize != 4096 */
1823 inode->i_blocks += num_blocks << 3;
1824 if (start_pos < inode->i_size) {
1825 /* FIXME blocksize != pagesize */
1826 ret = drop_extents(trans, root, inode,
1828 (pos + count + root->blocksize -1) &
1829 ~((u64)root->blocksize - 1));
1832 if (inode->i_size >= PAGE_CACHE_SIZE || pos + count < inode->i_size ||
1833 pos + count - start_pos > BTRFS_MAX_INLINE_DATA_SIZE(root)) {
1834 ret = btrfs_alloc_extent(trans, root, inode->i_ino,
1835 num_blocks, 1, (u64)-1, &ins);
1837 ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
1838 start_pos, ins.objectid, ins.offset);
1845 alloc_extent_start = ins.objectid;
1846 ret = btrfs_end_transaction(trans, root);
1847 mutex_unlock(&root->fs_info->fs_mutex);
1850 size_t offset = pos & (PAGE_CACHE_SIZE - 1);
1851 size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset);
1852 size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
1855 memset(pages, 0, sizeof(pages));
1856 ret = prepare_pages(root, file, pages, num_pages,
1857 pos, first_index, last_index,
1858 write_bytes, alloc_extent_start);
1861 /* FIXME blocks != pagesize */
1862 if (alloc_extent_start)
1863 alloc_extent_start += num_pages;
1864 ret = btrfs_copy_from_user(pos, num_pages,
1865 write_bytes, pages, buf);
1868 ret = dirty_and_release_pages(NULL, root, file, pages,
1869 num_pages, pos, write_bytes);
1871 btrfs_drop_pages(pages, num_pages);
1874 count -= write_bytes;
1876 num_written += write_bytes;
1878 balance_dirty_pages_ratelimited(inode->i_mapping);
1882 mutex_unlock(&inode->i_mutex);
1885 page_cache_release(pinned[0]);
1887 page_cache_release(pinned[1]);
1889 current->backing_dev_info = NULL;
1890 mark_inode_dirty(inode);
1891 return num_written ? num_written : err;
1894 static int btrfs_read_actor(read_descriptor_t *desc, struct page *page,
1895 unsigned long offset, unsigned long size)
1898 unsigned long left, count = desc->count;
1899 struct inode *inode = page->mapping->host;
1904 if (!PageChecked(page)) {
1905 /* FIXME, do it per block */
1906 struct btrfs_root *root = BTRFS_I(inode)->root;
1908 int ret = btrfs_csum_verify_file_block(root,
1909 page->mapping->host->i_ino,
1910 page->index << PAGE_CACHE_SHIFT,
1911 kmap(page), PAGE_CACHE_SIZE);
1913 printk("failed to verify ino %lu page %lu\n",
1914 page->mapping->host->i_ino,
1916 memset(page_address(page), 0, PAGE_CACHE_SIZE);
1918 SetPageChecked(page);
1922 * Faults on the destination of a read are common, so do it before
1925 if (!fault_in_pages_writeable(desc->arg.buf, size)) {
1926 kaddr = kmap_atomic(page, KM_USER0);
1927 left = __copy_to_user_inatomic(desc->arg.buf,
1928 kaddr + offset, size);
1929 kunmap_atomic(kaddr, KM_USER0);
1934 /* Do it the slow way */
1936 left = __copy_to_user(desc->arg.buf, kaddr + offset, size);
1941 desc->error = -EFAULT;
1944 desc->count = count - size;
1945 desc->written += size;
1946 desc->arg.buf += size;
1951 * btrfs_file_aio_read - filesystem read routine
1952 * @iocb: kernel I/O control block
1953 * @iov: io vector request
1954 * @nr_segs: number of segments in the iovec
1955 * @pos: current file position
1957 static ssize_t btrfs_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
1958 unsigned long nr_segs, loff_t pos)
1960 struct file *filp = iocb->ki_filp;
1964 loff_t *ppos = &iocb->ki_pos;
1967 for (seg = 0; seg < nr_segs; seg++) {
1968 const struct iovec *iv = &iov[seg];
1971 * If any segment has a negative length, or the cumulative
1972 * length ever wraps negative then return -EINVAL.
1974 count += iv->iov_len;
1975 if (unlikely((ssize_t)(count|iv->iov_len) < 0))
1977 if (access_ok(VERIFY_WRITE, iv->iov_base, iv->iov_len))
1982 count -= iv->iov_len; /* This segment is no good */
1987 for (seg = 0; seg < nr_segs; seg++) {
1988 read_descriptor_t desc;
1991 desc.arg.buf = iov[seg].iov_base;
1992 desc.count = iov[seg].iov_len;
1993 if (desc.count == 0)
1996 do_generic_file_read(filp, ppos, &desc,
1998 retval += desc.written;
2000 retval = retval ?: desc.error;
2008 static int create_subvol(struct btrfs_root *root, char *name, int namelen)
2010 struct btrfs_trans_handle *trans;
2011 struct btrfs_key key;
2012 struct btrfs_root_item root_item;
2013 struct btrfs_inode_item *inode_item;
2014 struct buffer_head *subvol;
2015 struct btrfs_leaf *leaf;
2016 struct btrfs_root *new_root;
2017 struct inode *inode;
2020 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
2022 mutex_lock(&root->fs_info->fs_mutex);
2023 trans = btrfs_start_transaction(root, 1);
2026 subvol = btrfs_alloc_free_block(trans, root);
2029 leaf = btrfs_buffer_leaf(subvol);
2030 btrfs_set_header_nritems(&leaf->header, 0);
2031 btrfs_set_header_level(&leaf->header, 0);
2032 btrfs_set_header_blocknr(&leaf->header, bh_blocknr(subvol));
2033 btrfs_set_header_generation(&leaf->header, trans->transid);
2034 btrfs_set_header_owner(&leaf->header, root->root_key.objectid);
2035 memcpy(leaf->header.fsid, root->fs_info->disk_super->fsid,
2036 sizeof(leaf->header.fsid));
2037 mark_buffer_dirty(subvol);
2039 inode_item = &root_item.inode;
2040 memset(inode_item, 0, sizeof(*inode_item));
2041 btrfs_set_inode_generation(inode_item, 1);
2042 btrfs_set_inode_size(inode_item, 3);
2043 btrfs_set_inode_nlink(inode_item, 1);
2044 btrfs_set_inode_nblocks(inode_item, 1);
2045 btrfs_set_inode_mode(inode_item, S_IFDIR | 0755);
2047 btrfs_set_root_blocknr(&root_item, bh_blocknr(subvol));
2048 btrfs_set_root_refs(&root_item, 1);
2052 ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
2056 btrfs_set_root_dirid(&root_item, new_dirid);
2058 key.objectid = objectid;
2061 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
2062 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
2067 * insert the directory item
2069 key.offset = (u64)-1;
2070 ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
2072 root->fs_info->sb->s_root->d_inode->i_ino,
2076 ret = btrfs_commit_transaction(trans, root);
2079 new_root = btrfs_read_fs_root(root->fs_info, &key);
2082 trans = btrfs_start_transaction(new_root, 1);
2085 inode = btrfs_new_inode(trans, new_root, new_dirid, S_IFDIR | 0700);
2086 inode->i_op = &btrfs_dir_inode_operations;
2087 inode->i_fop = &btrfs_dir_file_operations;
2089 ret = btrfs_make_empty_dir(trans, new_root, new_dirid, new_dirid);
2094 ret = btrfs_update_inode(trans, new_root, inode);
2097 ret = btrfs_commit_transaction(trans, new_root);
2102 mutex_unlock(&root->fs_info->fs_mutex);
2106 static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
2108 struct btrfs_trans_handle *trans;
2109 struct btrfs_key key;
2110 struct btrfs_root_item new_root_item;
2114 if (!root->ref_cows)
2117 mutex_lock(&root->fs_info->fs_mutex);
2118 trans = btrfs_start_transaction(root, 1);
2121 ret = btrfs_update_inode(trans, root, root->inode);
2124 ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
2128 memcpy(&new_root_item, &root->root_item,
2129 sizeof(new_root_item));
2131 key.objectid = objectid;
2134 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
2135 btrfs_set_root_blocknr(&new_root_item, bh_blocknr(root->node));
2137 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
2142 * insert the directory item
2144 key.offset = (u64)-1;
2145 ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
2147 root->fs_info->sb->s_root->d_inode->i_ino,
2152 ret = btrfs_inc_root_ref(trans, root);
2155 ret = btrfs_commit_transaction(trans, root);
2157 mutex_unlock(&root->fs_info->fs_mutex);
2161 static int add_disk(struct btrfs_root *root, char *name, int namelen)
2163 struct block_device *bdev;
2164 struct btrfs_path *path;
2165 struct super_block *sb = root->fs_info->sb;
2166 struct btrfs_root *dev_root = root->fs_info->dev_root;
2167 struct btrfs_trans_handle *trans;
2168 struct btrfs_device_item *dev_item;
2169 struct btrfs_key key;
2176 printk("adding disk %s\n", name);
2177 path = btrfs_alloc_path();
2180 num_blocks = btrfs_super_total_blocks(root->fs_info->disk_super);
2181 bdev = open_bdev_excl(name, O_RDWR, sb);
2183 ret = PTR_ERR(bdev);
2184 printk("open bdev excl failed ret %d\n", ret);
2187 set_blocksize(bdev, sb->s_blocksize);
2188 new_blocks = bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2189 key.objectid = num_blocks;
2190 key.offset = new_blocks;
2192 btrfs_set_key_type(&key, BTRFS_DEV_ITEM_KEY);
2194 mutex_lock(&dev_root->fs_info->fs_mutex);
2195 trans = btrfs_start_transaction(dev_root, 1);
2196 item_size = sizeof(*dev_item) + namelen;
2197 printk("insert empty on %Lu %Lu %u size %d\n", num_blocks, new_blocks, key.flags, item_size);
2198 ret = btrfs_insert_empty_item(trans, dev_root, path, &key, item_size);
2200 printk("insert failed %d\n", ret);
2201 close_bdev_excl(bdev);
2206 dev_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
2207 path->slots[0], struct btrfs_device_item);
2208 btrfs_set_device_pathlen(dev_item, namelen);
2209 memcpy(dev_item + 1, name, namelen);
2211 device_id = btrfs_super_last_device_id(root->fs_info->disk_super) + 1;
2212 btrfs_set_super_last_device_id(root->fs_info->disk_super, device_id);
2213 btrfs_set_device_id(dev_item, device_id);
2214 mark_buffer_dirty(path->nodes[0]);
2216 ret = btrfs_insert_dev_radix(root, bdev, device_id, num_blocks,
2220 btrfs_set_super_total_blocks(root->fs_info->disk_super,
2221 num_blocks + new_blocks);
2222 i_size_write(root->fs_info->btree_inode,
2223 (num_blocks + new_blocks) <<
2224 root->fs_info->btree_inode->i_blkbits);
2228 ret = btrfs_commit_transaction(trans, dev_root);
2230 mutex_unlock(&root->fs_info->fs_mutex);
2232 btrfs_free_path(path);
2237 static int btrfs_ioctl(struct inode *inode, struct file *filp, unsigned int
2238 cmd, unsigned long arg)
2240 struct btrfs_root *root = BTRFS_I(inode)->root;
2241 struct btrfs_ioctl_vol_args vol_args;
2243 struct btrfs_dir_item *di;
2245 struct btrfs_path *path;
2249 case BTRFS_IOC_SNAP_CREATE:
2250 if (copy_from_user(&vol_args,
2251 (struct btrfs_ioctl_vol_args __user *)arg,
2254 namelen = strlen(vol_args.name);
2255 if (namelen > BTRFS_VOL_NAME_MAX)
2257 path = btrfs_alloc_path();
2260 root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
2261 mutex_lock(&root->fs_info->fs_mutex);
2262 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
2264 vol_args.name, namelen, 0);
2265 mutex_unlock(&root->fs_info->fs_mutex);
2266 btrfs_free_path(path);
2267 if (di && !IS_ERR(di))
2270 if (root == root->fs_info->tree_root)
2271 ret = create_subvol(root, vol_args.name, namelen);
2273 ret = create_snapshot(root, vol_args.name, namelen);
2276 case BTRFS_IOC_ADD_DISK:
2277 if (copy_from_user(&vol_args,
2278 (struct btrfs_ioctl_vol_args __user *)arg,
2281 namelen = strlen(vol_args.name);
2282 if (namelen > BTRFS_VOL_NAME_MAX)
2284 vol_args.name[namelen] = '\0';
2285 ret = add_disk(root, vol_args.name, namelen);
2293 static struct kmem_cache *btrfs_inode_cachep;
2294 struct kmem_cache *btrfs_trans_handle_cachep;
2295 struct kmem_cache *btrfs_transaction_cachep;
2296 struct kmem_cache *btrfs_bit_radix_cachep;
2297 struct kmem_cache *btrfs_path_cachep;
2300 * Called inside transaction, so use GFP_NOFS
2302 static struct inode *btrfs_alloc_inode(struct super_block *sb)
2304 struct btrfs_inode *ei;
2306 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
2309 return &ei->vfs_inode;
2312 static void btrfs_destroy_inode(struct inode *inode)
2314 WARN_ON(!list_empty(&inode->i_dentry));
2315 WARN_ON(inode->i_data.nrpages);
2317 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
2320 static void init_once(void * foo, struct kmem_cache * cachep,
2321 unsigned long flags)
2323 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
2325 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
2326 SLAB_CTOR_CONSTRUCTOR) {
2327 inode_init_once(&ei->vfs_inode);
2331 static int init_inodecache(void)
2333 btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache",
2334 sizeof(struct btrfs_inode),
2335 0, (SLAB_RECLAIM_ACCOUNT|
2338 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache",
2339 sizeof(struct btrfs_trans_handle),
2340 0, (SLAB_RECLAIM_ACCOUNT|
2343 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache",
2344 sizeof(struct btrfs_transaction),
2345 0, (SLAB_RECLAIM_ACCOUNT|
2348 btrfs_path_cachep = kmem_cache_create("btrfs_path_cache",
2349 sizeof(struct btrfs_transaction),
2350 0, (SLAB_RECLAIM_ACCOUNT|
2353 btrfs_bit_radix_cachep = kmem_cache_create("btrfs_radix",
2355 0, (SLAB_RECLAIM_ACCOUNT|
2357 SLAB_DESTROY_BY_RCU),
2359 if (btrfs_inode_cachep == NULL || btrfs_trans_handle_cachep == NULL ||
2360 btrfs_transaction_cachep == NULL || btrfs_bit_radix_cachep == NULL)
2365 static void destroy_inodecache(void)
2367 kmem_cache_destroy(btrfs_inode_cachep);
2368 kmem_cache_destroy(btrfs_trans_handle_cachep);
2369 kmem_cache_destroy(btrfs_transaction_cachep);
2370 kmem_cache_destroy(btrfs_bit_radix_cachep);
2371 kmem_cache_destroy(btrfs_path_cachep);
2374 static int btrfs_get_sb(struct file_system_type *fs_type,
2375 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
2377 return get_sb_bdev(fs_type, flags, dev_name, data,
2378 btrfs_fill_super, mnt);
2382 static int btrfs_getattr(struct vfsmount *mnt,
2383 struct dentry *dentry, struct kstat *stat)
2385 struct inode *inode = dentry->d_inode;
2386 generic_fillattr(inode, stat);
2387 stat->blksize = 256 * 1024;
2391 static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
2393 struct btrfs_root *root = btrfs_sb(dentry->d_sb);
2394 struct btrfs_super_block *disk_super = root->fs_info->disk_super;
2396 buf->f_namelen = BTRFS_NAME_LEN;
2397 buf->f_blocks = btrfs_super_total_blocks(disk_super);
2398 buf->f_bfree = buf->f_blocks - btrfs_super_blocks_used(disk_super);
2399 buf->f_bavail = buf->f_bfree;
2400 buf->f_bsize = dentry->d_sb->s_blocksize;
2401 buf->f_type = BTRFS_SUPER_MAGIC;
2405 static struct file_system_type btrfs_fs_type = {
2406 .owner = THIS_MODULE,
2408 .get_sb = btrfs_get_sb,
2409 .kill_sb = kill_block_super,
2410 .fs_flags = FS_REQUIRES_DEV,
2413 static struct super_operations btrfs_super_ops = {
2414 .delete_inode = btrfs_delete_inode,
2415 .put_super = btrfs_put_super,
2416 .read_inode = btrfs_read_locked_inode,
2417 .write_super = btrfs_write_super,
2418 .sync_fs = btrfs_sync_fs,
2419 .write_inode = btrfs_write_inode,
2420 .dirty_inode = btrfs_dirty_inode,
2421 .alloc_inode = btrfs_alloc_inode,
2422 .destroy_inode = btrfs_destroy_inode,
2423 .statfs = btrfs_statfs,
2426 static struct inode_operations btrfs_dir_inode_operations = {
2427 .lookup = btrfs_lookup,
2428 .create = btrfs_create,
2429 .unlink = btrfs_unlink,
2430 .mkdir = btrfs_mkdir,
2431 .rmdir = btrfs_rmdir,
2434 static struct inode_operations btrfs_dir_ro_inode_operations = {
2435 .lookup = btrfs_lookup,
2438 static struct file_operations btrfs_dir_file_operations = {
2439 .llseek = generic_file_llseek,
2440 .read = generic_read_dir,
2441 .readdir = btrfs_readdir,
2442 .ioctl = btrfs_ioctl,
2445 static struct address_space_operations btrfs_aops = {
2446 .readpage = btrfs_readpage,
2447 .writepage = btrfs_writepage,
2448 .sync_page = block_sync_page,
2449 .prepare_write = btrfs_prepare_write,
2450 .commit_write = btrfs_commit_write,
2453 static struct inode_operations btrfs_file_inode_operations = {
2454 .truncate = btrfs_truncate,
2455 .getattr = btrfs_getattr,
2458 static struct file_operations btrfs_file_operations = {
2459 .llseek = generic_file_llseek,
2460 .read = do_sync_read,
2461 .aio_read = btrfs_file_aio_read,
2462 .write = btrfs_file_write,
2463 .mmap = generic_file_mmap,
2464 .open = generic_file_open,
2465 .ioctl = btrfs_ioctl,
2466 .fsync = btrfs_sync_file,
2469 static int __init init_btrfs_fs(void)
2472 printk("btrfs loaded!\n");
2473 err = init_inodecache();
2476 kset_set_kset_s(&btrfs_subsys, fs_subsys);
2477 err = subsystem_register(&btrfs_subsys);
2480 return register_filesystem(&btrfs_fs_type);
2482 destroy_inodecache();
2486 static void __exit exit_btrfs_fs(void)
2488 destroy_inodecache();
2489 unregister_filesystem(&btrfs_fs_type);
2490 subsystem_unregister(&btrfs_subsys);
2491 printk("btrfs unloaded\n");
2494 module_init(init_btrfs_fs)
2495 module_exit(exit_btrfs_fs)
2497 MODULE_LICENSE("GPL");