Btrfs: Avoid extent_buffer lru corruption
[safe/jmp/linux-2.6] / fs / btrfs / inode.c
1 /*
2  * Copyright (C) 2007 Oracle.  All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public
6  * License v2 as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11  * General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public
14  * License along with this program; if not, write to the
15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16  * Boston, MA 021110-1307, USA.
17  */
18
19 #include <linux/buffer_head.h>
20 #include <linux/fs.h>
21 #include <linux/pagemap.h>
22 #include <linux/highmem.h>
23 #include <linux/time.h>
24 #include <linux/init.h>
25 #include <linux/string.h>
26 #include <linux/smp_lock.h>
27 #include <linux/backing-dev.h>
28 #include <linux/mpage.h>
29 #include <linux/swap.h>
30 #include <linux/writeback.h>
31 #include <linux/statfs.h>
32 #include <linux/compat.h>
33 #include <linux/bit_spinlock.h>
34 #include <linux/version.h>
35 #include "ctree.h"
36 #include "disk-io.h"
37 #include "transaction.h"
38 #include "btrfs_inode.h"
39 #include "ioctl.h"
40 #include "print-tree.h"
41
42 struct btrfs_iget_args {
43         u64 ino;
44         struct btrfs_root *root;
45 };
46
47 static struct inode_operations btrfs_dir_inode_operations;
48 static struct inode_operations btrfs_symlink_inode_operations;
49 static struct inode_operations btrfs_dir_ro_inode_operations;
50 static struct inode_operations btrfs_special_inode_operations;
51 static struct inode_operations btrfs_file_inode_operations;
52 static struct address_space_operations btrfs_aops;
53 static struct address_space_operations btrfs_symlink_aops;
54 static struct file_operations btrfs_dir_file_operations;
55 static struct extent_map_ops btrfs_extent_map_ops;
56
57 static struct kmem_cache *btrfs_inode_cachep;
58 struct kmem_cache *btrfs_trans_handle_cachep;
59 struct kmem_cache *btrfs_transaction_cachep;
60 struct kmem_cache *btrfs_bit_radix_cachep;
61 struct kmem_cache *btrfs_path_cachep;
62
63 #define S_SHIFT 12
64 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
65         [S_IFREG >> S_SHIFT]    = BTRFS_FT_REG_FILE,
66         [S_IFDIR >> S_SHIFT]    = BTRFS_FT_DIR,
67         [S_IFCHR >> S_SHIFT]    = BTRFS_FT_CHRDEV,
68         [S_IFBLK >> S_SHIFT]    = BTRFS_FT_BLKDEV,
69         [S_IFIFO >> S_SHIFT]    = BTRFS_FT_FIFO,
70         [S_IFSOCK >> S_SHIFT]   = BTRFS_FT_SOCK,
71         [S_IFLNK >> S_SHIFT]    = BTRFS_FT_SYMLINK,
72 };
73
74 static int run_delalloc_range(struct inode *inode, u64 start, u64 end)
75 {
76         struct btrfs_root *root = BTRFS_I(inode)->root;
77         struct btrfs_trans_handle *trans;
78         struct btrfs_key ins;
79         u64 alloc_hint = 0;
80         u64 num_bytes;
81         int ret;
82         u64 blocksize = root->sectorsize;
83
84         mutex_lock(&root->fs_info->fs_mutex);
85         trans = btrfs_start_transaction(root, 1);
86         btrfs_set_trans_block_group(trans, inode);
87         BUG_ON(!trans);
88         num_bytes = (end - start + blocksize) & ~(blocksize - 1);
89         ret = btrfs_drop_extents(trans, root, inode,
90                                  start, start + num_bytes, start, &alloc_hint);
91
92         if (alloc_hint == EXTENT_MAP_INLINE)
93                 goto out;
94
95         ret = btrfs_alloc_extent(trans, root, inode->i_ino, num_bytes, 0,
96                                  alloc_hint, (u64)-1, &ins, 1);
97         if (ret) {
98                 WARN_ON(1);
99                 goto out;
100         }
101         ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
102                                        start, ins.objectid, ins.offset,
103                                        ins.offset);
104 out:
105         btrfs_end_transaction(trans, root);
106         mutex_unlock(&root->fs_info->fs_mutex);
107         return ret;
108 }
109
110 int btrfs_writepage_io_hook(struct page *page, u64 start, u64 end)
111 {
112         struct inode *inode = page->mapping->host;
113         struct btrfs_root *root = BTRFS_I(inode)->root;
114         struct btrfs_trans_handle *trans;
115         char *kaddr;
116         int ret;
117         u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
118         size_t offset = start - page_start;
119
120         mutex_lock(&root->fs_info->fs_mutex);
121         trans = btrfs_start_transaction(root, 1);
122         btrfs_set_trans_block_group(trans, inode);
123         kaddr = kmap(page);
124         btrfs_csum_file_block(trans, root, inode, inode->i_ino,
125                               start, kaddr + offset, end - start + 1);
126         kunmap(page);
127         ret = btrfs_end_transaction(trans, root);
128         BUG_ON(ret);
129         mutex_unlock(&root->fs_info->fs_mutex);
130         return ret;
131 }
132
133 int btrfs_readpage_io_hook(struct page *page, u64 start, u64 end)
134 {
135         int ret = 0;
136         struct inode *inode = page->mapping->host;
137         struct btrfs_root *root = BTRFS_I(inode)->root;
138         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
139         struct btrfs_csum_item *item;
140         struct btrfs_path *path = NULL;
141         u32 csum;
142
143         mutex_lock(&root->fs_info->fs_mutex);
144         path = btrfs_alloc_path();
145         item = btrfs_lookup_csum(NULL, root, path, inode->i_ino, start, 0);
146         if (IS_ERR(item)) {
147                 ret = PTR_ERR(item);
148                 /* a csum that isn't present is a preallocated region. */
149                 if (ret == -ENOENT || ret == -EFBIG)
150                         ret = 0;
151                 csum = 0;
152                 goto out;
153         }
154         read_extent_buffer(path->nodes[0], &csum, (unsigned long)item,
155                            BTRFS_CRC32_SIZE);
156         set_state_private(em_tree, start, csum);
157 out:
158         if (path)
159                 btrfs_free_path(path);
160         mutex_unlock(&root->fs_info->fs_mutex);
161         return ret;
162 }
163
164 int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end)
165 {
166         size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
167         struct inode *inode = page->mapping->host;
168         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
169         char *kaddr;
170         u64 private;
171         int ret;
172         struct btrfs_root *root = BTRFS_I(inode)->root;
173         u32 csum = ~(u32)0;
174         unsigned long flags;
175
176         ret = get_state_private(em_tree, start, &private);
177         local_irq_save(flags);
178         kaddr = kmap_atomic(page, KM_IRQ0);
179         if (ret) {
180                 goto zeroit;
181         }
182         csum = btrfs_csum_data(root, kaddr + offset, csum,  end - start + 1);
183         btrfs_csum_final(csum, (char *)&csum);
184         if (csum != private) {
185                 goto zeroit;
186         }
187         kunmap_atomic(kaddr, KM_IRQ0);
188         local_irq_restore(flags);
189         return 0;
190
191 zeroit:
192         printk("btrfs csum failed ino %lu off %llu\n",
193                page->mapping->host->i_ino, (unsigned long long)start);
194         memset(kaddr + offset, 1, end - start + 1);
195         flush_dcache_page(page);
196         kunmap_atomic(kaddr, KM_IRQ0);
197         local_irq_restore(flags);
198         return 0;
199 }
200
201 void btrfs_read_locked_inode(struct inode *inode)
202 {
203         struct btrfs_path *path;
204         struct extent_buffer *leaf;
205         struct btrfs_inode_item *inode_item;
206         struct btrfs_inode_timespec *tspec;
207         struct btrfs_root *root = BTRFS_I(inode)->root;
208         struct btrfs_key location;
209         u64 alloc_group_block;
210         u32 rdev;
211         int ret;
212
213         path = btrfs_alloc_path();
214         BUG_ON(!path);
215         mutex_lock(&root->fs_info->fs_mutex);
216
217         memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
218         ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
219         if (ret)
220                 goto make_bad;
221
222         leaf = path->nodes[0];
223         inode_item = btrfs_item_ptr(leaf, path->slots[0],
224                                     struct btrfs_inode_item);
225
226         inode->i_mode = btrfs_inode_mode(leaf, inode_item);
227         inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
228         inode->i_uid = btrfs_inode_uid(leaf, inode_item);
229         inode->i_gid = btrfs_inode_gid(leaf, inode_item);
230         inode->i_size = btrfs_inode_size(leaf, inode_item);
231
232         tspec = btrfs_inode_atime(inode_item);
233         inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
234         inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
235
236         tspec = btrfs_inode_mtime(inode_item);
237         inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
238         inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
239
240         tspec = btrfs_inode_ctime(inode_item);
241         inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
242         inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
243
244         inode->i_blocks = btrfs_inode_nblocks(leaf, inode_item);
245         inode->i_generation = btrfs_inode_generation(leaf, inode_item);
246         inode->i_rdev = 0;
247         rdev = btrfs_inode_rdev(leaf, inode_item);
248
249         alloc_group_block = btrfs_inode_block_group(leaf, inode_item);
250         BTRFS_I(inode)->block_group = btrfs_lookup_block_group(root->fs_info,
251                                                        alloc_group_block);
252
253         btrfs_free_path(path);
254         inode_item = NULL;
255
256         mutex_unlock(&root->fs_info->fs_mutex);
257
258         switch (inode->i_mode & S_IFMT) {
259         case S_IFREG:
260                 inode->i_mapping->a_ops = &btrfs_aops;
261                 BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
262                 inode->i_fop = &btrfs_file_operations;
263                 inode->i_op = &btrfs_file_inode_operations;
264                 break;
265         case S_IFDIR:
266                 inode->i_fop = &btrfs_dir_file_operations;
267                 if (root == root->fs_info->tree_root)
268                         inode->i_op = &btrfs_dir_ro_inode_operations;
269                 else
270                         inode->i_op = &btrfs_dir_inode_operations;
271                 break;
272         case S_IFLNK:
273                 inode->i_op = &btrfs_symlink_inode_operations;
274                 inode->i_mapping->a_ops = &btrfs_symlink_aops;
275                 break;
276         default:
277                 init_special_inode(inode, inode->i_mode, rdev);
278                 break;
279         }
280         return;
281
282 make_bad:
283         btrfs_release_path(root, path);
284         btrfs_free_path(path);
285         mutex_unlock(&root->fs_info->fs_mutex);
286         make_bad_inode(inode);
287 }
288
289 static void fill_inode_item(struct extent_buffer *leaf,
290                             struct btrfs_inode_item *item,
291                             struct inode *inode)
292 {
293         btrfs_set_inode_uid(leaf, item, inode->i_uid);
294         btrfs_set_inode_gid(leaf, item, inode->i_gid);
295         btrfs_set_inode_size(leaf, item, inode->i_size);
296         btrfs_set_inode_mode(leaf, item, inode->i_mode);
297         btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
298
299         btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
300                                inode->i_atime.tv_sec);
301         btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
302                                 inode->i_atime.tv_nsec);
303
304         btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
305                                inode->i_mtime.tv_sec);
306         btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
307                                 inode->i_mtime.tv_nsec);
308
309         btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
310                                inode->i_ctime.tv_sec);
311         btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
312                                 inode->i_ctime.tv_nsec);
313
314         btrfs_set_inode_nblocks(leaf, item, inode->i_blocks);
315         btrfs_set_inode_generation(leaf, item, inode->i_generation);
316         btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
317         btrfs_set_inode_block_group(leaf, item,
318                                     BTRFS_I(inode)->block_group->key.objectid);
319 }
320
321 int btrfs_update_inode(struct btrfs_trans_handle *trans,
322                               struct btrfs_root *root,
323                               struct inode *inode)
324 {
325         struct btrfs_inode_item *inode_item;
326         struct btrfs_path *path;
327         struct extent_buffer *leaf;
328         int ret;
329
330         path = btrfs_alloc_path();
331         BUG_ON(!path);
332         ret = btrfs_lookup_inode(trans, root, path,
333                                  &BTRFS_I(inode)->location, 1);
334         if (ret) {
335                 if (ret > 0)
336                         ret = -ENOENT;
337                 goto failed;
338         }
339
340         leaf = path->nodes[0];
341         inode_item = btrfs_item_ptr(leaf, path->slots[0],
342                                   struct btrfs_inode_item);
343
344         fill_inode_item(leaf, inode_item, inode);
345         btrfs_mark_buffer_dirty(leaf);
346         btrfs_set_inode_last_trans(trans, inode);
347         ret = 0;
348 failed:
349         btrfs_release_path(root, path);
350         btrfs_free_path(path);
351         return ret;
352 }
353
354
355 static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
356                               struct btrfs_root *root,
357                               struct inode *dir,
358                               struct dentry *dentry)
359 {
360         struct btrfs_path *path;
361         const char *name = dentry->d_name.name;
362         int name_len = dentry->d_name.len;
363         int ret = 0;
364         struct extent_buffer *leaf;
365         struct btrfs_dir_item *di;
366         struct btrfs_key key;
367
368         path = btrfs_alloc_path();
369         if (!path) {
370                 ret = -ENOMEM;
371                 goto err;
372         }
373
374         di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
375                                     name, name_len, -1);
376         if (IS_ERR(di)) {
377                 ret = PTR_ERR(di);
378                 goto err;
379         }
380         if (!di) {
381                 ret = -ENOENT;
382                 goto err;
383         }
384         leaf = path->nodes[0];
385         btrfs_dir_item_key_to_cpu(leaf, di, &key);
386         ret = btrfs_delete_one_dir_name(trans, root, path, di);
387         if (ret)
388                 goto err;
389         btrfs_release_path(root, path);
390
391         di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
392                                          key.objectid, name, name_len, -1);
393         if (IS_ERR(di)) {
394                 ret = PTR_ERR(di);
395                 goto err;
396         }
397         if (!di) {
398                 ret = -ENOENT;
399                 goto err;
400         }
401         ret = btrfs_delete_one_dir_name(trans, root, path, di);
402
403         dentry->d_inode->i_ctime = dir->i_ctime;
404 err:
405         btrfs_free_path(path);
406         if (!ret) {
407                 dir->i_size -= name_len * 2;
408                 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
409                 btrfs_update_inode(trans, root, dir);
410                 drop_nlink(dentry->d_inode);
411                 ret = btrfs_update_inode(trans, root, dentry->d_inode);
412                 dir->i_sb->s_dirt = 1;
413         }
414         return ret;
415 }
416
417 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
418 {
419         struct btrfs_root *root;
420         struct btrfs_trans_handle *trans;
421         int ret;
422         unsigned long nr;
423
424         root = BTRFS_I(dir)->root;
425         mutex_lock(&root->fs_info->fs_mutex);
426         trans = btrfs_start_transaction(root, 1);
427
428         btrfs_set_trans_block_group(trans, dir);
429         ret = btrfs_unlink_trans(trans, root, dir, dentry);
430         nr = trans->blocks_used;
431
432         btrfs_end_transaction(trans, root);
433         mutex_unlock(&root->fs_info->fs_mutex);
434         btrfs_btree_balance_dirty(root, nr);
435
436         return ret;
437 }
438
439 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
440 {
441         struct inode *inode = dentry->d_inode;
442         int err;
443         int ret;
444         struct btrfs_root *root = BTRFS_I(dir)->root;
445         struct btrfs_path *path;
446         struct btrfs_key key;
447         struct btrfs_trans_handle *trans;
448         struct btrfs_key found_key;
449         int found_type;
450         struct extent_buffer *leaf;
451         char *goodnames = "..";
452         unsigned long nr;
453
454         if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
455                 return -ENOTEMPTY;
456
457         path = btrfs_alloc_path();
458         BUG_ON(!path);
459         mutex_lock(&root->fs_info->fs_mutex);
460         trans = btrfs_start_transaction(root, 1);
461
462         btrfs_set_trans_block_group(trans, dir);
463         key.objectid = inode->i_ino;
464         key.offset = (u64)-1;
465         key.type = (u8)-1;
466         while(1) {
467                 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
468                 if (ret < 0) {
469                         err = ret;
470                         goto out;
471                 }
472                 BUG_ON(ret == 0);
473                 if (path->slots[0] == 0) {
474                         err = -ENOENT;
475                         goto out;
476                 }
477                 path->slots[0]--;
478                 leaf = path->nodes[0];
479                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
480                 found_type = btrfs_key_type(&found_key);
481                 if (found_key.objectid != inode->i_ino) {
482                         err = -ENOENT;
483                         goto out;
484                 }
485                 if ((found_type != BTRFS_DIR_ITEM_KEY &&
486                      found_type != BTRFS_DIR_INDEX_KEY) ||
487                     (!btrfs_match_dir_item_name(root, path, goodnames, 2) &&
488                     !btrfs_match_dir_item_name(root, path, goodnames, 1))) {
489                         err = -ENOTEMPTY;
490                         goto out;
491                 }
492                 ret = btrfs_del_item(trans, root, path);
493                 BUG_ON(ret);
494
495                 if (found_type == BTRFS_DIR_ITEM_KEY && found_key.offset == 1)
496                         break;
497                 btrfs_release_path(root, path);
498         }
499         ret = 0;
500         btrfs_release_path(root, path);
501
502         /* now the directory is empty */
503         err = btrfs_unlink_trans(trans, root, dir, dentry);
504         if (!err) {
505                 inode->i_size = 0;
506         }
507 out:
508         btrfs_release_path(root, path);
509         btrfs_free_path(path);
510         nr = trans->blocks_used;
511         ret = btrfs_end_transaction(trans, root);
512         mutex_unlock(&root->fs_info->fs_mutex);
513         btrfs_btree_balance_dirty(root, nr);
514         if (ret && !err)
515                 err = ret;
516         return err;
517 }
518
519 static int btrfs_free_inode(struct btrfs_trans_handle *trans,
520                             struct btrfs_root *root,
521                             struct inode *inode)
522 {
523         struct btrfs_path *path;
524         int ret;
525
526         clear_inode(inode);
527
528         path = btrfs_alloc_path();
529         BUG_ON(!path);
530         ret = btrfs_lookup_inode(trans, root, path,
531                                  &BTRFS_I(inode)->location, -1);
532         if (ret > 0)
533                 ret = -ENOENT;
534         if (!ret)
535                 ret = btrfs_del_item(trans, root, path);
536         btrfs_free_path(path);
537         return ret;
538 }
539
540 /*
541  * this can truncate away extent items, csum items and directory items.
542  * It starts at a high offset and removes keys until it can't find
543  * any higher than i_size.
544  *
545  * csum items that cross the new i_size are truncated to the new size
546  * as well.
547  */
548 static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
549                                    struct btrfs_root *root,
550                                    struct inode *inode)
551 {
552         int ret;
553         struct btrfs_path *path;
554         struct btrfs_key key;
555         struct btrfs_key found_key;
556         u32 found_type;
557         struct extent_buffer *leaf;
558         struct btrfs_file_extent_item *fi;
559         u64 extent_start = 0;
560         u64 extent_num_bytes = 0;
561         u64 item_end = 0;
562         int found_extent;
563         int del_item;
564         int extent_type = -1;
565
566         btrfs_drop_extent_cache(inode, inode->i_size, (u64)-1);
567         path = btrfs_alloc_path();
568         path->reada = -1;
569         BUG_ON(!path);
570
571         /* FIXME, add redo link to tree so we don't leak on crash */
572         key.objectid = inode->i_ino;
573         key.offset = (u64)-1;
574         key.type = (u8)-1;
575
576         while(1) {
577                 btrfs_init_path(path);
578                 fi = NULL;
579                 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
580                 if (ret < 0) {
581                         goto error;
582                 }
583                 if (ret > 0) {
584                         BUG_ON(path->slots[0] == 0);
585                         path->slots[0]--;
586                 }
587                 leaf = path->nodes[0];
588                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
589                 found_type = btrfs_key_type(&found_key);
590
591                 if (found_key.objectid != inode->i_ino)
592                         break;
593
594                 if (found_type != BTRFS_CSUM_ITEM_KEY &&
595                     found_type != BTRFS_DIR_ITEM_KEY &&
596                     found_type != BTRFS_DIR_INDEX_KEY &&
597                     found_type != BTRFS_EXTENT_DATA_KEY)
598                         break;
599
600                 item_end = found_key.offset;
601                 if (found_type == BTRFS_EXTENT_DATA_KEY) {
602                         fi = btrfs_item_ptr(leaf, path->slots[0],
603                                             struct btrfs_file_extent_item);
604                         extent_type = btrfs_file_extent_type(leaf, fi);
605                         if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
606                                 item_end +=
607                                     btrfs_file_extent_num_bytes(leaf, fi);
608                         } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
609                                 struct btrfs_item *item = btrfs_item_nr(leaf,
610                                                                 path->slots[0]);
611                                 item_end += btrfs_file_extent_inline_len(leaf,
612                                                                          item);
613                         }
614                         item_end--;
615                 }
616                 if (found_type == BTRFS_CSUM_ITEM_KEY) {
617                         ret = btrfs_csum_truncate(trans, root, path,
618                                                   inode->i_size);
619                         BUG_ON(ret);
620                 }
621                 if (item_end < inode->i_size) {
622                         if (found_type == BTRFS_DIR_ITEM_KEY) {
623                                 found_type = BTRFS_INODE_ITEM_KEY;
624                         } else if (found_type == BTRFS_EXTENT_ITEM_KEY) {
625                                 found_type = BTRFS_CSUM_ITEM_KEY;
626                         } else if (found_type) {
627                                 found_type--;
628                         } else {
629                                 break;
630                         }
631                         btrfs_set_key_type(&key, found_type);
632                         btrfs_release_path(root, path);
633                         continue;
634                 }
635                 if (found_key.offset >= inode->i_size)
636                         del_item = 1;
637                 else
638                         del_item = 0;
639                 found_extent = 0;
640
641                 /* FIXME, shrink the extent if the ref count is only 1 */
642                 if (found_type != BTRFS_EXTENT_DATA_KEY)
643                         goto delete;
644
645                 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
646                         u64 num_dec;
647                         extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
648                         if (!del_item) {
649                                 u64 orig_num_bytes =
650                                         btrfs_file_extent_num_bytes(leaf, fi);
651                                 extent_num_bytes = inode->i_size -
652                                         found_key.offset + root->sectorsize - 1;
653                                 btrfs_set_file_extent_num_bytes(leaf, fi,
654                                                          extent_num_bytes);
655                                 num_dec = (orig_num_bytes -
656                                            extent_num_bytes) >> 9;
657                                 if (extent_start != 0) {
658                                         inode->i_blocks -= num_dec;
659                                 }
660                                 btrfs_mark_buffer_dirty(leaf);
661                         } else {
662                                 extent_num_bytes =
663                                         btrfs_file_extent_disk_num_bytes(leaf,
664                                                                          fi);
665                                 /* FIXME blocksize != 4096 */
666                                 num_dec = btrfs_file_extent_num_bytes(leaf,
667                                                                        fi) >> 9;
668                                 if (extent_start != 0) {
669                                         found_extent = 1;
670                                         inode->i_blocks -= num_dec;
671                                 }
672                         }
673                 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE &&
674                            !del_item) {
675                         u32 newsize = inode->i_size - found_key.offset;
676                         newsize = btrfs_file_extent_calc_inline_size(newsize);
677                         ret = btrfs_truncate_item(trans, root, path,
678                                                   newsize, 1);
679                         BUG_ON(ret);
680                 }
681 delete:
682                 if (del_item) {
683                         ret = btrfs_del_item(trans, root, path);
684                         if (ret)
685                                 goto error;
686                 } else {
687                         break;
688                 }
689                 btrfs_release_path(root, path);
690                 if (found_extent) {
691                         ret = btrfs_free_extent(trans, root, extent_start,
692                                                 extent_num_bytes, 0);
693                         BUG_ON(ret);
694                 }
695         }
696         ret = 0;
697 error:
698         btrfs_release_path(root, path);
699         btrfs_free_path(path);
700         inode->i_sb->s_dirt = 1;
701         return ret;
702 }
703
704 static int btrfs_cow_one_page(struct inode *inode, struct page *page,
705                               size_t zero_start)
706 {
707         char *kaddr;
708         int ret = 0;
709         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
710         u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
711         u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
712
713         set_page_extent_mapped(page);
714
715         lock_extent(em_tree, page_start, page_end, GFP_NOFS);
716         set_extent_delalloc(&BTRFS_I(inode)->extent_tree, page_start,
717                             page_end, GFP_NOFS);
718         if (zero_start != PAGE_CACHE_SIZE) {
719                 kaddr = kmap(page);
720                 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
721                 flush_dcache_page(page);
722                 kunmap(page);
723         }
724         set_page_dirty(page);
725         unlock_extent(em_tree, page_start, page_end, GFP_NOFS);
726
727         return ret;
728 }
729
730 /*
731  * taken from block_truncate_page, but does cow as it zeros out
732  * any bytes left in the last page in the file.
733  */
734 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
735 {
736         struct inode *inode = mapping->host;
737         struct btrfs_root *root = BTRFS_I(inode)->root;
738         u32 blocksize = root->sectorsize;
739         pgoff_t index = from >> PAGE_CACHE_SHIFT;
740         unsigned offset = from & (PAGE_CACHE_SIZE-1);
741         struct page *page;
742         int ret = 0;
743         u64 page_start;
744
745         if ((offset & (blocksize - 1)) == 0)
746                 goto out;
747
748         down_read(&root->snap_sem);
749         ret = -ENOMEM;
750         page = grab_cache_page(mapping, index);
751         if (!page)
752                 goto out;
753         if (!PageUptodate(page)) {
754                 ret = btrfs_readpage(NULL, page);
755                 lock_page(page);
756                 if (!PageUptodate(page)) {
757                         ret = -EIO;
758                         goto out;
759                 }
760         }
761         page_start = (u64)page->index << PAGE_CACHE_SHIFT;
762
763         ret = btrfs_cow_one_page(inode, page, offset);
764
765         unlock_page(page);
766         page_cache_release(page);
767         up_read(&BTRFS_I(inode)->root->snap_sem);
768 out:
769         return ret;
770 }
771
772 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
773 {
774         struct inode *inode = dentry->d_inode;
775         int err;
776
777         err = inode_change_ok(inode, attr);
778         if (err)
779                 return err;
780
781         if (S_ISREG(inode->i_mode) &&
782             attr->ia_valid & ATTR_SIZE && attr->ia_size > inode->i_size) {
783                 struct btrfs_trans_handle *trans;
784                 struct btrfs_root *root = BTRFS_I(inode)->root;
785                 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
786
787                 u64 mask = root->sectorsize - 1;
788                 u64 pos = (inode->i_size + mask) & ~mask;
789                 u64 block_end = attr->ia_size | mask;
790                 u64 hole_size;
791                 u64 alloc_hint = 0;
792
793                 if (attr->ia_size <= pos)
794                         goto out;
795
796                 btrfs_truncate_page(inode->i_mapping, inode->i_size);
797
798                 lock_extent(em_tree, pos, block_end, GFP_NOFS);
799                 hole_size = (attr->ia_size - pos + mask) & ~mask;
800
801                 mutex_lock(&root->fs_info->fs_mutex);
802                 trans = btrfs_start_transaction(root, 1);
803                 btrfs_set_trans_block_group(trans, inode);
804                 err = btrfs_drop_extents(trans, root, inode,
805                                          pos, pos + hole_size, pos,
806                                          &alloc_hint);
807
808                 if (alloc_hint != EXTENT_MAP_INLINE) {
809                         err = btrfs_insert_file_extent(trans, root,
810                                                        inode->i_ino,
811                                                        pos, 0, 0, hole_size);
812                 }
813                 btrfs_end_transaction(trans, root);
814                 mutex_unlock(&root->fs_info->fs_mutex);
815                 unlock_extent(em_tree, pos, block_end, GFP_NOFS);
816                 if (err)
817                         return err;
818         }
819 out:
820         err = inode_setattr(inode, attr);
821
822         return err;
823 }
824 void btrfs_delete_inode(struct inode *inode)
825 {
826         struct btrfs_trans_handle *trans;
827         struct btrfs_root *root = BTRFS_I(inode)->root;
828         unsigned long nr;
829         int ret;
830
831         truncate_inode_pages(&inode->i_data, 0);
832         if (is_bad_inode(inode)) {
833                 goto no_delete;
834         }
835
836         inode->i_size = 0;
837         mutex_lock(&root->fs_info->fs_mutex);
838         trans = btrfs_start_transaction(root, 1);
839
840         btrfs_set_trans_block_group(trans, inode);
841         ret = btrfs_truncate_in_trans(trans, root, inode);
842         if (ret)
843                 goto no_delete_lock;
844         ret = btrfs_free_inode(trans, root, inode);
845         if (ret)
846                 goto no_delete_lock;
847         nr = trans->blocks_used;
848
849         btrfs_end_transaction(trans, root);
850         mutex_unlock(&root->fs_info->fs_mutex);
851         btrfs_btree_balance_dirty(root, nr);
852         return;
853
854 no_delete_lock:
855         nr = trans->blocks_used;
856         btrfs_end_transaction(trans, root);
857         mutex_unlock(&root->fs_info->fs_mutex);
858         btrfs_btree_balance_dirty(root, nr);
859 no_delete:
860         clear_inode(inode);
861 }
862
863 /*
864  * this returns the key found in the dir entry in the location pointer.
865  * If no dir entries were found, location->objectid is 0.
866  */
867 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
868                                struct btrfs_key *location)
869 {
870         const char *name = dentry->d_name.name;
871         int namelen = dentry->d_name.len;
872         struct btrfs_dir_item *di;
873         struct btrfs_path *path;
874         struct btrfs_root *root = BTRFS_I(dir)->root;
875         int ret = 0;
876
877         path = btrfs_alloc_path();
878         BUG_ON(!path);
879         di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
880                                     namelen, 0);
881         if (IS_ERR(di))
882                 ret = PTR_ERR(di);
883         if (!di || IS_ERR(di)) {
884                 location->objectid = 0;
885                 goto out;
886         }
887         btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
888 out:
889         btrfs_release_path(root, path);
890         btrfs_free_path(path);
891         return ret;
892 }
893
894 /*
895  * when we hit a tree root in a directory, the btrfs part of the inode
896  * needs to be changed to reflect the root directory of the tree root.  This
897  * is kind of like crossing a mount point.
898  */
899 static int fixup_tree_root_location(struct btrfs_root *root,
900                              struct btrfs_key *location,
901                              struct btrfs_root **sub_root,
902                              struct dentry *dentry)
903 {
904         struct btrfs_path *path;
905         struct btrfs_root_item *ri;
906
907         if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
908                 return 0;
909         if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
910                 return 0;
911
912         path = btrfs_alloc_path();
913         BUG_ON(!path);
914         mutex_lock(&root->fs_info->fs_mutex);
915
916         *sub_root = btrfs_read_fs_root(root->fs_info, location,
917                                         dentry->d_name.name,
918                                         dentry->d_name.len);
919         if (IS_ERR(*sub_root))
920                 return PTR_ERR(*sub_root);
921
922         ri = &(*sub_root)->root_item;
923         location->objectid = btrfs_root_dirid(ri);
924         btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
925         location->offset = 0;
926
927         btrfs_free_path(path);
928         mutex_unlock(&root->fs_info->fs_mutex);
929         return 0;
930 }
931
932 static int btrfs_init_locked_inode(struct inode *inode, void *p)
933 {
934         struct btrfs_iget_args *args = p;
935         inode->i_ino = args->ino;
936         BTRFS_I(inode)->root = args->root;
937         extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
938                              inode->i_mapping, GFP_NOFS);
939         return 0;
940 }
941
942 static int btrfs_find_actor(struct inode *inode, void *opaque)
943 {
944         struct btrfs_iget_args *args = opaque;
945         return (args->ino == inode->i_ino &&
946                 args->root == BTRFS_I(inode)->root);
947 }
948
949 struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
950                                 struct btrfs_root *root)
951 {
952         struct inode *inode;
953         struct btrfs_iget_args args;
954         args.ino = objectid;
955         args.root = root;
956
957         inode = iget5_locked(s, objectid, btrfs_find_actor,
958                              btrfs_init_locked_inode,
959                              (void *)&args);
960         return inode;
961 }
962
963 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
964                                    struct nameidata *nd)
965 {
966         struct inode * inode;
967         struct btrfs_inode *bi = BTRFS_I(dir);
968         struct btrfs_root *root = bi->root;
969         struct btrfs_root *sub_root = root;
970         struct btrfs_key location;
971         int ret;
972
973         if (dentry->d_name.len > BTRFS_NAME_LEN)
974                 return ERR_PTR(-ENAMETOOLONG);
975
976         mutex_lock(&root->fs_info->fs_mutex);
977         ret = btrfs_inode_by_name(dir, dentry, &location);
978         mutex_unlock(&root->fs_info->fs_mutex);
979
980         if (ret < 0)
981                 return ERR_PTR(ret);
982
983         inode = NULL;
984         if (location.objectid) {
985                 ret = fixup_tree_root_location(root, &location, &sub_root,
986                                                 dentry);
987                 if (ret < 0)
988                         return ERR_PTR(ret);
989                 if (ret > 0)
990                         return ERR_PTR(-ENOENT);
991                 inode = btrfs_iget_locked(dir->i_sb, location.objectid,
992                                           sub_root);
993                 if (!inode)
994                         return ERR_PTR(-EACCES);
995                 if (inode->i_state & I_NEW) {
996                         /* the inode and parent dir are two different roots */
997                         if (sub_root != root) {
998                                 igrab(inode);
999                                 sub_root->inode = inode;
1000                         }
1001                         BTRFS_I(inode)->root = sub_root;
1002                         memcpy(&BTRFS_I(inode)->location, &location,
1003                                sizeof(location));
1004                         btrfs_read_locked_inode(inode);
1005                         unlock_new_inode(inode);
1006                 }
1007         }
1008         return d_splice_alias(inode, dentry);
1009 }
1010
1011 static unsigned char btrfs_filetype_table[] = {
1012         DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
1013 };
1014
1015 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
1016 {
1017         struct inode *inode = filp->f_path.dentry->d_inode;
1018         struct btrfs_root *root = BTRFS_I(inode)->root;
1019         struct btrfs_item *item;
1020         struct btrfs_dir_item *di;
1021         struct btrfs_key key;
1022         struct btrfs_key found_key;
1023         struct btrfs_path *path;
1024         int ret;
1025         u32 nritems;
1026         struct extent_buffer *leaf;
1027         int slot;
1028         int advance;
1029         unsigned char d_type;
1030         int over = 0;
1031         u32 di_cur;
1032         u32 di_total;
1033         u32 di_len;
1034         int key_type = BTRFS_DIR_INDEX_KEY;
1035         char tmp_name[32];
1036         char *name_ptr;
1037         int name_len;
1038
1039         /* FIXME, use a real flag for deciding about the key type */
1040         if (root->fs_info->tree_root == root)
1041                 key_type = BTRFS_DIR_ITEM_KEY;
1042
1043         mutex_lock(&root->fs_info->fs_mutex);
1044         key.objectid = inode->i_ino;
1045         btrfs_set_key_type(&key, key_type);
1046         key.offset = filp->f_pos;
1047
1048         path = btrfs_alloc_path();
1049         path->reada = 2;
1050         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1051         if (ret < 0)
1052                 goto err;
1053         advance = 0;
1054         while(1) {
1055                 leaf = path->nodes[0];
1056                 nritems = btrfs_header_nritems(leaf);
1057                 slot = path->slots[0];
1058                 if (advance || slot >= nritems) {
1059                         if (slot >= nritems -1) {
1060                                 ret = btrfs_next_leaf(root, path);
1061                                 if (ret)
1062                                         break;
1063                                 leaf = path->nodes[0];
1064                                 nritems = btrfs_header_nritems(leaf);
1065                                 slot = path->slots[0];
1066                         } else {
1067                                 slot++;
1068                                 path->slots[0]++;
1069                         }
1070                 }
1071                 advance = 1;
1072                 item = btrfs_item_nr(leaf, slot);
1073                 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1074
1075                 if (found_key.objectid != key.objectid)
1076                         break;
1077                 if (btrfs_key_type(&found_key) != key_type)
1078                         break;
1079                 if (found_key.offset < filp->f_pos)
1080                         continue;
1081
1082                 filp->f_pos = found_key.offset;
1083                 advance = 1;
1084                 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
1085                 di_cur = 0;
1086                 di_total = btrfs_item_size(leaf, item);
1087                 while(di_cur < di_total) {
1088                         struct btrfs_key location;
1089
1090                         name_len = btrfs_dir_name_len(leaf, di);
1091                         if (name_len < 32) {
1092                                 name_ptr = tmp_name;
1093                         } else {
1094                                 name_ptr = kmalloc(name_len, GFP_NOFS);
1095                                 BUG_ON(!name_ptr);
1096                         }
1097                         read_extent_buffer(leaf, name_ptr,
1098                                            (unsigned long)(di + 1), name_len);
1099
1100                         d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
1101                         btrfs_dir_item_key_to_cpu(leaf, di, &location);
1102
1103                         over = filldir(dirent, name_ptr, name_len,
1104                                        found_key.offset,
1105                                        location.objectid,
1106                                        d_type);
1107
1108                         if (name_ptr != tmp_name)
1109                                 kfree(name_ptr);
1110
1111                         if (over)
1112                                 goto nopos;
1113                         di_len = btrfs_dir_name_len(leaf, di) + sizeof(*di);
1114                         di_cur += di_len;
1115                         di = (struct btrfs_dir_item *)((char *)di + di_len);
1116                 }
1117         }
1118         filp->f_pos++;
1119 nopos:
1120         ret = 0;
1121 err:
1122         btrfs_release_path(root, path);
1123         btrfs_free_path(path);
1124         mutex_unlock(&root->fs_info->fs_mutex);
1125         return ret;
1126 }
1127
1128 int btrfs_write_inode(struct inode *inode, int wait)
1129 {
1130         struct btrfs_root *root = BTRFS_I(inode)->root;
1131         struct btrfs_trans_handle *trans;
1132         int ret = 0;
1133
1134         if (wait) {
1135                 mutex_lock(&root->fs_info->fs_mutex);
1136                 trans = btrfs_start_transaction(root, 1);
1137                 btrfs_set_trans_block_group(trans, inode);
1138                 ret = btrfs_commit_transaction(trans, root);
1139                 mutex_unlock(&root->fs_info->fs_mutex);
1140         }
1141         return ret;
1142 }
1143
1144 /*
1145  * This is somewhat expensive, updating the tree every time the
1146  * inode changes.  But, it is most likely to find the inode in cache.
1147  * FIXME, needs more benchmarking...there are no reasons other than performance
1148  * to keep or drop this code.
1149  */
1150 void btrfs_dirty_inode(struct inode *inode)
1151 {
1152         struct btrfs_root *root = BTRFS_I(inode)->root;
1153         struct btrfs_trans_handle *trans;
1154
1155         mutex_lock(&root->fs_info->fs_mutex);
1156         trans = btrfs_start_transaction(root, 1);
1157         btrfs_set_trans_block_group(trans, inode);
1158         btrfs_update_inode(trans, root, inode);
1159         btrfs_end_transaction(trans, root);
1160         mutex_unlock(&root->fs_info->fs_mutex);
1161 }
1162
1163 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
1164                                      struct btrfs_root *root,
1165                                      u64 objectid,
1166                                      struct btrfs_block_group_cache *group,
1167                                      int mode)
1168 {
1169         struct inode *inode;
1170         struct btrfs_inode_item *inode_item;
1171         struct btrfs_key *location;
1172         struct btrfs_path *path;
1173         int ret;
1174         int owner;
1175
1176         path = btrfs_alloc_path();
1177         BUG_ON(!path);
1178
1179         inode = new_inode(root->fs_info->sb);
1180         if (!inode)
1181                 return ERR_PTR(-ENOMEM);
1182
1183         extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
1184                              inode->i_mapping, GFP_NOFS);
1185         BTRFS_I(inode)->root = root;
1186
1187         if (mode & S_IFDIR)
1188                 owner = 0;
1189         else
1190                 owner = 1;
1191         group = btrfs_find_block_group(root, group, 0, 0, owner);
1192         BTRFS_I(inode)->block_group = group;
1193
1194         ret = btrfs_insert_empty_inode(trans, root, path, objectid);
1195         if (ret)
1196                 goto fail;
1197
1198         inode->i_uid = current->fsuid;
1199         inode->i_gid = current->fsgid;
1200         inode->i_mode = mode;
1201         inode->i_ino = objectid;
1202         inode->i_blocks = 0;
1203         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1204         inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1205                                   struct btrfs_inode_item);
1206         fill_inode_item(path->nodes[0], inode_item, inode);
1207         btrfs_mark_buffer_dirty(path->nodes[0]);
1208         btrfs_free_path(path);
1209
1210         location = &BTRFS_I(inode)->location;
1211         location->objectid = objectid;
1212         location->offset = 0;
1213         btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
1214
1215         insert_inode_hash(inode);
1216         return inode;
1217 fail:
1218         btrfs_free_path(path);
1219         return ERR_PTR(ret);
1220 }
1221
1222 static inline u8 btrfs_inode_type(struct inode *inode)
1223 {
1224         return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
1225 }
1226
1227 static int btrfs_add_link(struct btrfs_trans_handle *trans,
1228                             struct dentry *dentry, struct inode *inode)
1229 {
1230         int ret;
1231         struct btrfs_key key;
1232         struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
1233         struct inode *parent_inode;
1234
1235         key.objectid = inode->i_ino;
1236         btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
1237         key.offset = 0;
1238
1239         ret = btrfs_insert_dir_item(trans, root,
1240                                     dentry->d_name.name, dentry->d_name.len,
1241                                     dentry->d_parent->d_inode->i_ino,
1242                                     &key, btrfs_inode_type(inode));
1243         if (ret == 0) {
1244                 parent_inode = dentry->d_parent->d_inode;
1245                 parent_inode->i_size += dentry->d_name.len * 2;
1246                 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
1247                 ret = btrfs_update_inode(trans, root,
1248                                          dentry->d_parent->d_inode);
1249         }
1250         return ret;
1251 }
1252
1253 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
1254                             struct dentry *dentry, struct inode *inode)
1255 {
1256         int err = btrfs_add_link(trans, dentry, inode);
1257         if (!err) {
1258                 d_instantiate(dentry, inode);
1259                 return 0;
1260         }
1261         if (err > 0)
1262                 err = -EEXIST;
1263         return err;
1264 }
1265
1266 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
1267                         int mode, dev_t rdev)
1268 {
1269         struct btrfs_trans_handle *trans;
1270         struct btrfs_root *root = BTRFS_I(dir)->root;
1271         struct inode *inode;
1272         int err;
1273         int drop_inode = 0;
1274         u64 objectid;
1275         unsigned long nr;
1276
1277         if (!new_valid_dev(rdev))
1278                 return -EINVAL;
1279
1280         mutex_lock(&root->fs_info->fs_mutex);
1281         trans = btrfs_start_transaction(root, 1);
1282         btrfs_set_trans_block_group(trans, dir);
1283
1284         err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1285         if (err) {
1286                 err = -ENOSPC;
1287                 goto out_unlock;
1288         }
1289
1290         inode = btrfs_new_inode(trans, root, objectid,
1291                                 BTRFS_I(dir)->block_group, mode);
1292         err = PTR_ERR(inode);
1293         if (IS_ERR(inode))
1294                 goto out_unlock;
1295
1296         btrfs_set_trans_block_group(trans, inode);
1297         err = btrfs_add_nondir(trans, dentry, inode);
1298         if (err)
1299                 drop_inode = 1;
1300         else {
1301                 inode->i_op = &btrfs_special_inode_operations;
1302                 init_special_inode(inode, inode->i_mode, rdev);
1303                 btrfs_update_inode(trans, root, inode);
1304         }
1305         dir->i_sb->s_dirt = 1;
1306         btrfs_update_inode_block_group(trans, inode);
1307         btrfs_update_inode_block_group(trans, dir);
1308 out_unlock:
1309         nr = trans->blocks_used;
1310         btrfs_end_transaction(trans, root);
1311         mutex_unlock(&root->fs_info->fs_mutex);
1312
1313         if (drop_inode) {
1314                 inode_dec_link_count(inode);
1315                 iput(inode);
1316         }
1317         btrfs_btree_balance_dirty(root, nr);
1318         return err;
1319 }
1320
1321 static int btrfs_create(struct inode *dir, struct dentry *dentry,
1322                         int mode, struct nameidata *nd)
1323 {
1324         struct btrfs_trans_handle *trans;
1325         struct btrfs_root *root = BTRFS_I(dir)->root;
1326         struct inode *inode;
1327         int err;
1328         int drop_inode = 0;
1329         unsigned long nr;
1330         u64 objectid;
1331
1332         mutex_lock(&root->fs_info->fs_mutex);
1333         trans = btrfs_start_transaction(root, 1);
1334         btrfs_set_trans_block_group(trans, dir);
1335
1336         err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1337         if (err) {
1338                 err = -ENOSPC;
1339                 goto out_unlock;
1340         }
1341
1342         inode = btrfs_new_inode(trans, root, objectid,
1343                                 BTRFS_I(dir)->block_group, mode);
1344         err = PTR_ERR(inode);
1345         if (IS_ERR(inode))
1346                 goto out_unlock;
1347
1348         btrfs_set_trans_block_group(trans, inode);
1349         err = btrfs_add_nondir(trans, dentry, inode);
1350         if (err)
1351                 drop_inode = 1;
1352         else {
1353                 inode->i_mapping->a_ops = &btrfs_aops;
1354                 inode->i_fop = &btrfs_file_operations;
1355                 inode->i_op = &btrfs_file_inode_operations;
1356                 extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
1357                                      inode->i_mapping, GFP_NOFS);
1358                 BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
1359         }
1360         dir->i_sb->s_dirt = 1;
1361         btrfs_update_inode_block_group(trans, inode);
1362         btrfs_update_inode_block_group(trans, dir);
1363 out_unlock:
1364         nr = trans->blocks_used;
1365         btrfs_end_transaction(trans, root);
1366         mutex_unlock(&root->fs_info->fs_mutex);
1367
1368         if (drop_inode) {
1369                 inode_dec_link_count(inode);
1370                 iput(inode);
1371         }
1372         btrfs_btree_balance_dirty(root, nr);
1373         return err;
1374 }
1375
1376 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
1377                       struct dentry *dentry)
1378 {
1379         struct btrfs_trans_handle *trans;
1380         struct btrfs_root *root = BTRFS_I(dir)->root;
1381         struct inode *inode = old_dentry->d_inode;
1382         unsigned long nr;
1383         int err;
1384         int drop_inode = 0;
1385
1386         if (inode->i_nlink == 0)
1387                 return -ENOENT;
1388
1389         inc_nlink(inode);
1390         mutex_lock(&root->fs_info->fs_mutex);
1391         trans = btrfs_start_transaction(root, 1);
1392
1393         btrfs_set_trans_block_group(trans, dir);
1394         atomic_inc(&inode->i_count);
1395         err = btrfs_add_nondir(trans, dentry, inode);
1396
1397         if (err)
1398                 drop_inode = 1;
1399
1400         dir->i_sb->s_dirt = 1;
1401         btrfs_update_inode_block_group(trans, dir);
1402         err = btrfs_update_inode(trans, root, inode);
1403
1404         if (err)
1405                 drop_inode = 1;
1406
1407         nr = trans->blocks_used;
1408         btrfs_end_transaction(trans, root);
1409         mutex_unlock(&root->fs_info->fs_mutex);
1410
1411         if (drop_inode) {
1412                 inode_dec_link_count(inode);
1413                 iput(inode);
1414         }
1415         btrfs_btree_balance_dirty(root, nr);
1416         return err;
1417 }
1418
1419 static int btrfs_make_empty_dir(struct btrfs_trans_handle *trans,
1420                                 struct btrfs_root *root,
1421                                 u64 objectid, u64 dirid)
1422 {
1423         int ret;
1424         char buf[2];
1425         struct btrfs_key key;
1426
1427         buf[0] = '.';
1428         buf[1] = '.';
1429
1430         key.objectid = objectid;
1431         key.offset = 0;
1432         btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
1433
1434         ret = btrfs_insert_dir_item(trans, root, buf, 1, objectid,
1435                                     &key, BTRFS_FT_DIR);
1436         if (ret)
1437                 goto error;
1438
1439         key.objectid = dirid;
1440         ret = btrfs_insert_dir_item(trans, root, buf, 2, objectid,
1441                                     &key, BTRFS_FT_DIR);
1442         if (ret)
1443                 goto error;
1444 error:
1445         return ret;
1446 }
1447
1448 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
1449 {
1450         struct inode *inode;
1451         struct btrfs_trans_handle *trans;
1452         struct btrfs_root *root = BTRFS_I(dir)->root;
1453         int err = 0;
1454         int drop_on_err = 0;
1455         u64 objectid;
1456         unsigned long nr = 1;
1457
1458         mutex_lock(&root->fs_info->fs_mutex);
1459         trans = btrfs_start_transaction(root, 1);
1460         btrfs_set_trans_block_group(trans, dir);
1461
1462         if (IS_ERR(trans)) {
1463                 err = PTR_ERR(trans);
1464                 goto out_unlock;
1465         }
1466
1467         err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1468         if (err) {
1469                 err = -ENOSPC;
1470                 goto out_unlock;
1471         }
1472
1473         inode = btrfs_new_inode(trans, root, objectid,
1474                                 BTRFS_I(dir)->block_group, S_IFDIR | mode);
1475         if (IS_ERR(inode)) {
1476                 err = PTR_ERR(inode);
1477                 goto out_fail;
1478         }
1479
1480         drop_on_err = 1;
1481         inode->i_op = &btrfs_dir_inode_operations;
1482         inode->i_fop = &btrfs_dir_file_operations;
1483         btrfs_set_trans_block_group(trans, inode);
1484
1485         err = btrfs_make_empty_dir(trans, root, inode->i_ino, dir->i_ino);
1486         if (err)
1487                 goto out_fail;
1488
1489         inode->i_size = 6;
1490         err = btrfs_update_inode(trans, root, inode);
1491         if (err)
1492                 goto out_fail;
1493
1494         err = btrfs_add_link(trans, dentry, inode);
1495         if (err)
1496                 goto out_fail;
1497
1498         d_instantiate(dentry, inode);
1499         drop_on_err = 0;
1500         dir->i_sb->s_dirt = 1;
1501         btrfs_update_inode_block_group(trans, inode);
1502         btrfs_update_inode_block_group(trans, dir);
1503
1504 out_fail:
1505         nr = trans->blocks_used;
1506         btrfs_end_transaction(trans, root);
1507
1508 out_unlock:
1509         mutex_unlock(&root->fs_info->fs_mutex);
1510         if (drop_on_err)
1511                 iput(inode);
1512         btrfs_btree_balance_dirty(root, nr);
1513         return err;
1514 }
1515
1516 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
1517                                     size_t page_offset, u64 start, u64 end,
1518                                     int create)
1519 {
1520         int ret;
1521         int err = 0;
1522         u64 bytenr;
1523         u64 extent_start = 0;
1524         u64 extent_end = 0;
1525         u64 objectid = inode->i_ino;
1526         u32 found_type;
1527         int failed_insert = 0;
1528         struct btrfs_path *path;
1529         struct btrfs_root *root = BTRFS_I(inode)->root;
1530         struct btrfs_file_extent_item *item;
1531         struct extent_buffer *leaf;
1532         struct btrfs_key found_key;
1533         struct extent_map *em = NULL;
1534         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1535         struct btrfs_trans_handle *trans = NULL;
1536
1537         path = btrfs_alloc_path();
1538         BUG_ON(!path);
1539         mutex_lock(&root->fs_info->fs_mutex);
1540
1541 again:
1542         em = lookup_extent_mapping(em_tree, start, end);
1543         if (em) {
1544                 goto out;
1545         }
1546         if (!em) {
1547                 em = alloc_extent_map(GFP_NOFS);
1548                 if (!em) {
1549                         err = -ENOMEM;
1550                         goto out;
1551                 }
1552                 em->start = EXTENT_MAP_HOLE;
1553                 em->end = EXTENT_MAP_HOLE;
1554         }
1555         em->bdev = inode->i_sb->s_bdev;
1556         ret = btrfs_lookup_file_extent(trans, root, path,
1557                                        objectid, start, trans != NULL);
1558         if (ret < 0) {
1559                 err = ret;
1560                 goto out;
1561         }
1562
1563         if (ret != 0) {
1564                 if (path->slots[0] == 0)
1565                         goto not_found;
1566                 path->slots[0]--;
1567         }
1568
1569         leaf = path->nodes[0];
1570         item = btrfs_item_ptr(leaf, path->slots[0],
1571                               struct btrfs_file_extent_item);
1572         /* are we inside the extent that was found? */
1573         btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1574         found_type = btrfs_key_type(&found_key);
1575         if (found_key.objectid != objectid ||
1576             found_type != BTRFS_EXTENT_DATA_KEY) {
1577                 goto not_found;
1578         }
1579
1580         found_type = btrfs_file_extent_type(leaf, item);
1581         extent_start = found_key.offset;
1582         if (found_type == BTRFS_FILE_EXTENT_REG) {
1583                 extent_end = extent_start +
1584                        btrfs_file_extent_num_bytes(leaf, item);
1585                 err = 0;
1586                 if (start < extent_start || start >= extent_end) {
1587                         em->start = start;
1588                         if (start < extent_start) {
1589                                 if (end < extent_start)
1590                                         goto not_found;
1591                                 em->end = extent_end - 1;
1592                         } else {
1593                                 em->end = end;
1594                         }
1595                         goto not_found_em;
1596                 }
1597                 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
1598                 if (bytenr == 0) {
1599                         em->start = extent_start;
1600                         em->end = extent_end - 1;
1601                         em->block_start = EXTENT_MAP_HOLE;
1602                         em->block_end = EXTENT_MAP_HOLE;
1603                         goto insert;
1604                 }
1605                 bytenr += btrfs_file_extent_offset(leaf, item);
1606                 em->block_start = bytenr;
1607                 em->block_end = em->block_start +
1608                         btrfs_file_extent_num_bytes(leaf, item) - 1;
1609                 em->start = extent_start;
1610                 em->end = extent_end - 1;
1611                 goto insert;
1612         } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
1613                 unsigned long ptr;
1614                 char *map;
1615                 size_t size;
1616                 size_t extent_offset;
1617                 size_t copy_size;
1618
1619                 size = btrfs_file_extent_inline_len(leaf, btrfs_item_nr(leaf,
1620                                                     path->slots[0]));
1621                 extent_end = (extent_start + size - 1) |
1622                         ((u64)root->sectorsize - 1);
1623                 if (start < extent_start || start >= extent_end) {
1624                         em->start = start;
1625                         if (start < extent_start) {
1626                                 if (end < extent_start)
1627                                         goto not_found;
1628                                 em->end = extent_end;
1629                         } else {
1630                                 em->end = end;
1631                         }
1632                         goto not_found_em;
1633                 }
1634                 em->block_start = EXTENT_MAP_INLINE;
1635                 em->block_end = EXTENT_MAP_INLINE;
1636
1637                 if (!page) {
1638                         em->start = extent_start;
1639                         em->end = extent_start + size - 1;
1640                         goto out;
1641                 }
1642
1643                 extent_offset = ((u64)page->index << PAGE_CACHE_SHIFT) -
1644                         extent_start + page_offset;
1645                 copy_size = min_t(u64, PAGE_CACHE_SIZE - page_offset,
1646                                 size - extent_offset);
1647                 em->start = extent_start + extent_offset;
1648                 em->end = (em->start + copy_size -1) |
1649                         ((u64)root->sectorsize -1);
1650                 map = kmap(page);
1651                 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
1652                 if (create == 0 && !PageUptodate(page)) {
1653                         read_extent_buffer(leaf, map + page_offset, ptr,
1654                                            copy_size);
1655                         flush_dcache_page(page);
1656                 } else if (create && PageUptodate(page)) {
1657                         if (!trans) {
1658                                 kunmap(page);
1659                                 free_extent_map(em);
1660                                 em = NULL;
1661                                 btrfs_release_path(root, path);
1662                                 trans = btrfs_start_transaction(root, 1);
1663                                 goto again;
1664                         }
1665                         write_extent_buffer(leaf, map + page_offset, ptr,
1666                                             copy_size);
1667                         btrfs_mark_buffer_dirty(leaf);
1668                 }
1669                 kunmap(page);
1670                 set_extent_uptodate(em_tree, em->start, em->end, GFP_NOFS);
1671                 goto insert;
1672         } else {
1673                 printk("unkknown found_type %d\n", found_type);
1674                 WARN_ON(1);
1675         }
1676 not_found:
1677         em->start = start;
1678         em->end = end;
1679 not_found_em:
1680         em->block_start = EXTENT_MAP_HOLE;
1681         em->block_end = EXTENT_MAP_HOLE;
1682 insert:
1683         btrfs_release_path(root, path);
1684         if (em->start > start || em->end < start) {
1685                 printk("bad extent! em: [%Lu %Lu] passed [%Lu %Lu]\n", em->start, em->end, start, end);
1686                 err = -EIO;
1687                 goto out;
1688         }
1689         ret = add_extent_mapping(em_tree, em);
1690         if (ret == -EEXIST) {
1691                 free_extent_map(em);
1692                 em = NULL;
1693                 failed_insert++;
1694                 if (failed_insert > 5) {
1695                         printk("failing to insert %Lu %Lu\n", start, end);
1696                         err = -EIO;
1697                         goto out;
1698                 }
1699                 goto again;
1700         }
1701         err = 0;
1702 out:
1703         btrfs_free_path(path);
1704         if (trans) {
1705                 ret = btrfs_end_transaction(trans, root);
1706                 if (!err)
1707                         err = ret;
1708         }
1709         mutex_unlock(&root->fs_info->fs_mutex);
1710         if (err) {
1711                 free_extent_map(em);
1712                 WARN_ON(1);
1713                 return ERR_PTR(err);
1714         }
1715         return em;
1716 }
1717
1718 static sector_t btrfs_bmap(struct address_space *mapping, sector_t iblock)
1719 {
1720         return extent_bmap(mapping, iblock, btrfs_get_extent);
1721 }
1722
1723 static int btrfs_prepare_write(struct file *file, struct page *page,
1724                                unsigned from, unsigned to)
1725 {
1726         return extent_prepare_write(&BTRFS_I(page->mapping->host)->extent_tree,
1727                                     page->mapping->host, page, from, to,
1728                                     btrfs_get_extent);
1729 }
1730
1731 int btrfs_readpage(struct file *file, struct page *page)
1732 {
1733         struct extent_map_tree *tree;
1734         tree = &BTRFS_I(page->mapping->host)->extent_tree;
1735         return extent_read_full_page(tree, page, btrfs_get_extent);
1736 }
1737 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
1738 {
1739         struct extent_map_tree *tree;
1740
1741
1742         if (current->flags & PF_MEMALLOC) {
1743                 redirty_page_for_writepage(wbc, page);
1744                 unlock_page(page);
1745                 return 0;
1746         }
1747         tree = &BTRFS_I(page->mapping->host)->extent_tree;
1748         return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
1749 }
1750
1751
1752 static int btrfs_writepages(struct address_space *mapping,
1753                             struct writeback_control *wbc)
1754 {
1755         struct extent_map_tree *tree;
1756         tree = &BTRFS_I(mapping->host)->extent_tree;
1757         return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
1758 }
1759
1760 static int btrfs_releasepage(struct page *page, gfp_t unused_gfp_flags)
1761 {
1762         struct extent_map_tree *tree;
1763         int ret;
1764
1765         tree = &BTRFS_I(page->mapping->host)->extent_tree;
1766         ret = try_release_extent_mapping(tree, page);
1767         if (ret == 1) {
1768                 ClearPagePrivate(page);
1769                 set_page_private(page, 0);
1770                 page_cache_release(page);
1771         }
1772         return ret;
1773 }
1774
1775 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
1776 {
1777         struct extent_map_tree *tree;
1778
1779         tree = &BTRFS_I(page->mapping->host)->extent_tree;
1780         extent_invalidatepage(tree, page, offset);
1781         btrfs_releasepage(page, GFP_NOFS);
1782 }
1783
1784 /*
1785  * btrfs_page_mkwrite() is not allowed to change the file size as it gets
1786  * called from a page fault handler when a page is first dirtied. Hence we must
1787  * be careful to check for EOF conditions here. We set the page up correctly
1788  * for a written page which means we get ENOSPC checking when writing into
1789  * holes and correct delalloc and unwritten extent mapping on filesystems that
1790  * support these features.
1791  *
1792  * We are not allowed to take the i_mutex here so we have to play games to
1793  * protect against truncate races as the page could now be beyond EOF.  Because
1794  * vmtruncate() writes the inode size before removing pages, once we have the
1795  * page lock we can determine safely if the page is beyond EOF. If it is not
1796  * beyond EOF, then the page is guaranteed safe against truncation until we
1797  * unlock the page.
1798  */
1799 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
1800 {
1801         struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
1802         unsigned long end;
1803         loff_t size;
1804         int ret = -EINVAL;
1805         u64 page_start;
1806
1807         down_read(&BTRFS_I(inode)->root->snap_sem);
1808         lock_page(page);
1809         wait_on_page_writeback(page);
1810         size = i_size_read(inode);
1811         page_start = (u64)page->index << PAGE_CACHE_SHIFT;
1812
1813         if ((page->mapping != inode->i_mapping) ||
1814             (page_start > size)) {
1815                 /* page got truncated out from underneath us */
1816                 goto out_unlock;
1817         }
1818
1819         /* page is wholly or partially inside EOF */
1820         if (page_start + PAGE_CACHE_SIZE > size)
1821                 end = size & ~PAGE_CACHE_MASK;
1822         else
1823                 end = PAGE_CACHE_SIZE;
1824
1825         ret = btrfs_cow_one_page(inode, page, end);
1826
1827 out_unlock:
1828         up_read(&BTRFS_I(inode)->root->snap_sem);
1829         unlock_page(page);
1830         return ret;
1831 }
1832
1833 static void btrfs_truncate(struct inode *inode)
1834 {
1835         struct btrfs_root *root = BTRFS_I(inode)->root;
1836         int ret;
1837         struct btrfs_trans_handle *trans;
1838         unsigned long nr;
1839
1840         if (!S_ISREG(inode->i_mode))
1841                 return;
1842         if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
1843                 return;
1844
1845         btrfs_truncate_page(inode->i_mapping, inode->i_size);
1846
1847         mutex_lock(&root->fs_info->fs_mutex);
1848         trans = btrfs_start_transaction(root, 1);
1849         btrfs_set_trans_block_group(trans, inode);
1850
1851         /* FIXME, add redo link to tree so we don't leak on crash */
1852         ret = btrfs_truncate_in_trans(trans, root, inode);
1853         btrfs_update_inode(trans, root, inode);
1854         nr = trans->blocks_used;
1855
1856         ret = btrfs_end_transaction(trans, root);
1857         BUG_ON(ret);
1858         mutex_unlock(&root->fs_info->fs_mutex);
1859         btrfs_btree_balance_dirty(root, nr);
1860 }
1861
1862 int btrfs_commit_write(struct file *file, struct page *page,
1863                        unsigned from, unsigned to)
1864 {
1865         return extent_commit_write(&BTRFS_I(page->mapping->host)->extent_tree,
1866                                    page->mapping->host, page, from, to);
1867 }
1868
1869 static int create_subvol(struct btrfs_root *root, char *name, int namelen)
1870 {
1871         struct btrfs_trans_handle *trans;
1872         struct btrfs_key key;
1873         struct btrfs_root_item root_item;
1874         struct btrfs_inode_item *inode_item;
1875         struct extent_buffer *leaf;
1876         struct btrfs_root *new_root;
1877         struct inode *inode;
1878         struct inode *dir;
1879         int ret;
1880         int err;
1881         u64 objectid;
1882         u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
1883         unsigned long nr = 1;
1884
1885         mutex_lock(&root->fs_info->fs_mutex);
1886         trans = btrfs_start_transaction(root, 1);
1887         BUG_ON(!trans);
1888
1889         leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0, 0);
1890         if (IS_ERR(leaf))
1891                 return PTR_ERR(leaf);
1892
1893         btrfs_set_header_nritems(leaf, 0);
1894         btrfs_set_header_level(leaf, 0);
1895         btrfs_set_header_bytenr(leaf, leaf->start);
1896         btrfs_set_header_generation(leaf, trans->transid);
1897         btrfs_set_header_owner(leaf, root->root_key.objectid);
1898         write_extent_buffer(leaf, root->fs_info->fsid,
1899                             (unsigned long)btrfs_header_fsid(leaf),
1900                             BTRFS_FSID_SIZE);
1901         btrfs_mark_buffer_dirty(leaf);
1902
1903         inode_item = &root_item.inode;
1904         memset(inode_item, 0, sizeof(*inode_item));
1905         inode_item->generation = cpu_to_le64(1);
1906         inode_item->size = cpu_to_le64(3);
1907         inode_item->nlink = cpu_to_le32(1);
1908         inode_item->nblocks = cpu_to_le64(1);
1909         inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
1910
1911         btrfs_set_root_bytenr(&root_item, leaf->start);
1912         btrfs_set_root_level(&root_item, 0);
1913         btrfs_set_root_refs(&root_item, 1);
1914         btrfs_set_root_used(&root_item, 0);
1915
1916         memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
1917         root_item.drop_level = 0;
1918
1919         free_extent_buffer(leaf);
1920         leaf = NULL;
1921
1922         ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
1923                                        0, &objectid);
1924         if (ret)
1925                 goto fail;
1926
1927         btrfs_set_root_dirid(&root_item, new_dirid);
1928
1929         key.objectid = objectid;
1930         key.offset = 1;
1931         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
1932         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
1933                                 &root_item);
1934         if (ret)
1935                 goto fail;
1936
1937         /*
1938          * insert the directory item
1939          */
1940         key.offset = (u64)-1;
1941         dir = root->fs_info->sb->s_root->d_inode;
1942         ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
1943                                     name, namelen, dir->i_ino, &key,
1944                                     BTRFS_FT_DIR);
1945         if (ret)
1946                 goto fail;
1947
1948         ret = btrfs_commit_transaction(trans, root);
1949         if (ret)
1950                 goto fail_commit;
1951
1952         new_root = btrfs_read_fs_root(root->fs_info, &key, name, namelen);
1953         BUG_ON(!new_root);
1954
1955         trans = btrfs_start_transaction(new_root, 1);
1956         BUG_ON(!trans);
1957
1958         inode = btrfs_new_inode(trans, new_root, new_dirid,
1959                                 BTRFS_I(dir)->block_group, S_IFDIR | 0700);
1960         if (IS_ERR(inode))
1961                 goto fail;
1962         inode->i_op = &btrfs_dir_inode_operations;
1963         inode->i_fop = &btrfs_dir_file_operations;
1964         new_root->inode = inode;
1965
1966         ret = btrfs_make_empty_dir(trans, new_root, new_dirid, new_dirid);
1967         if (ret)
1968                 goto fail;
1969
1970         inode->i_nlink = 1;
1971         inode->i_size = 6;
1972         ret = btrfs_update_inode(trans, new_root, inode);
1973         if (ret)
1974                 goto fail;
1975 fail:
1976         nr = trans->blocks_used;
1977         err = btrfs_commit_transaction(trans, root);
1978         if (err && !ret)
1979                 ret = err;
1980 fail_commit:
1981         mutex_unlock(&root->fs_info->fs_mutex);
1982         btrfs_btree_balance_dirty(root, nr);
1983         return ret;
1984 }
1985
1986 static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
1987 {
1988         struct btrfs_trans_handle *trans;
1989         struct btrfs_key key;
1990         struct btrfs_root_item new_root_item;
1991         struct extent_buffer *tmp;
1992         int ret;
1993         int err;
1994         u64 objectid;
1995         unsigned long nr;
1996
1997         if (!root->ref_cows)
1998                 return -EINVAL;
1999
2000         down_write(&root->snap_sem);
2001         freeze_bdev(root->fs_info->sb->s_bdev);
2002         thaw_bdev(root->fs_info->sb->s_bdev, root->fs_info->sb);
2003
2004         mutex_lock(&root->fs_info->fs_mutex);
2005         trans = btrfs_start_transaction(root, 1);
2006         BUG_ON(!trans);
2007
2008         ret = btrfs_update_inode(trans, root, root->inode);
2009         if (ret)
2010                 goto fail;
2011
2012         ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
2013                                        0, &objectid);
2014         if (ret)
2015                 goto fail;
2016
2017         memcpy(&new_root_item, &root->root_item,
2018                sizeof(new_root_item));
2019
2020         key.objectid = objectid;
2021         key.offset = 1;
2022         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
2023
2024         btrfs_cow_block(trans, root, root->node, NULL, 0, &tmp);
2025         btrfs_set_root_bytenr(&new_root_item, root->node->start);
2026         btrfs_set_root_level(&new_root_item, btrfs_header_level(root->node));
2027
2028         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
2029                                 &new_root_item);
2030         if (ret)
2031                 goto fail;
2032
2033         /*
2034          * insert the directory item
2035          */
2036         key.offset = (u64)-1;
2037         ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
2038                                     name, namelen,
2039                                     root->fs_info->sb->s_root->d_inode->i_ino,
2040                                     &key, BTRFS_FT_DIR);
2041
2042         if (ret)
2043                 goto fail;
2044
2045         ret = btrfs_inc_root_ref(trans, root);
2046         if (ret)
2047                 goto fail;
2048 fail:
2049         nr = trans->blocks_used;
2050         err = btrfs_commit_transaction(trans, root);
2051
2052         if (err && !ret)
2053                 ret = err;
2054
2055         mutex_unlock(&root->fs_info->fs_mutex);
2056         up_write(&root->snap_sem);
2057         btrfs_btree_balance_dirty(root, nr);
2058         return ret;
2059 }
2060
2061 static unsigned long force_ra(struct address_space *mapping,
2062                               struct file_ra_state *ra, struct file *file,
2063                               pgoff_t offset, pgoff_t last_index)
2064 {
2065         pgoff_t req_size;
2066
2067 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
2068         req_size = last_index - offset + 1;
2069         offset = page_cache_readahead(mapping, ra, file, offset, req_size);
2070         return offset;
2071 #else
2072         req_size = min(last_index - offset + 1, (pgoff_t)128);
2073         page_cache_sync_readahead(mapping, ra, file, offset, req_size);
2074         return offset + req_size;
2075 #endif
2076 }
2077
2078 int btrfs_defrag_file(struct file *file) {
2079         struct inode *inode = file->f_path.dentry->d_inode;
2080         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
2081         struct page *page;
2082         unsigned long last_index;
2083         unsigned long ra_index = 0;
2084         u64 page_start;
2085         u64 page_end;
2086         unsigned long i;
2087
2088         mutex_lock(&inode->i_mutex);
2089         last_index = inode->i_size >> PAGE_CACHE_SHIFT;
2090         for (i = 0; i <= last_index; i++) {
2091                 if (i == ra_index) {
2092                         ra_index = force_ra(inode->i_mapping, &file->f_ra,
2093                                             file, ra_index, last_index);
2094                 }
2095                 page = grab_cache_page(inode->i_mapping, i);
2096                 if (!page)
2097                         goto out_unlock;
2098                 if (!PageUptodate(page)) {
2099                         btrfs_readpage(NULL, page);
2100                         lock_page(page);
2101                         if (!PageUptodate(page)) {
2102                                 unlock_page(page);
2103                                 page_cache_release(page);
2104                                 goto out_unlock;
2105                         }
2106                 }
2107                 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2108                 page_end = page_start + PAGE_CACHE_SIZE - 1;
2109
2110                 lock_extent(em_tree, page_start, page_end, GFP_NOFS);
2111                 set_extent_delalloc(em_tree, page_start,
2112                                     page_end, GFP_NOFS);
2113                 unlock_extent(em_tree, page_start, page_end, GFP_NOFS);
2114                 set_page_dirty(page);
2115                 unlock_page(page);
2116                 page_cache_release(page);
2117                 balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);
2118         }
2119
2120 out_unlock:
2121         mutex_unlock(&inode->i_mutex);
2122         return 0;
2123 }
2124
2125 static int btrfs_ioctl_snap_create(struct btrfs_root *root, void __user *arg)
2126 {
2127         struct btrfs_ioctl_vol_args vol_args;
2128         struct btrfs_dir_item *di;
2129         struct btrfs_path *path;
2130         int namelen;
2131         u64 root_dirid;
2132
2133         if (copy_from_user(&vol_args, arg, sizeof(vol_args)))
2134                 return -EFAULT;
2135
2136         namelen = strlen(vol_args.name);
2137         if (namelen > BTRFS_VOL_NAME_MAX)
2138                 return -EINVAL;
2139         if (strchr(vol_args.name, '/'))
2140                 return -EINVAL;
2141
2142         path = btrfs_alloc_path();
2143         if (!path)
2144                 return -ENOMEM;
2145
2146         root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
2147         mutex_lock(&root->fs_info->fs_mutex);
2148         di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
2149                             path, root_dirid,
2150                             vol_args.name, namelen, 0);
2151         mutex_unlock(&root->fs_info->fs_mutex);
2152         btrfs_free_path(path);
2153         if (di && !IS_ERR(di))
2154                 return -EEXIST;
2155         if (IS_ERR(di))
2156                 return PTR_ERR(di);
2157
2158         if (root == root->fs_info->tree_root)
2159                 return create_subvol(root, vol_args.name, namelen);
2160         return create_snapshot(root, vol_args.name, namelen);
2161 }
2162
2163 static int btrfs_ioctl_defrag(struct file *file)
2164 {
2165         struct inode *inode = file->f_path.dentry->d_inode;
2166         struct btrfs_root *root = BTRFS_I(inode)->root;
2167
2168         switch (inode->i_mode & S_IFMT) {
2169         case S_IFDIR:
2170                 mutex_lock(&root->fs_info->fs_mutex);
2171                 btrfs_defrag_root(root, 0);
2172                 btrfs_defrag_root(root->fs_info->extent_root, 0);
2173                 mutex_unlock(&root->fs_info->fs_mutex);
2174                 break;
2175         case S_IFREG:
2176                 btrfs_defrag_file(file);
2177                 break;
2178         }
2179
2180         return 0;
2181 }
2182
2183 long btrfs_ioctl(struct file *file, unsigned int
2184                 cmd, unsigned long arg)
2185 {
2186         struct btrfs_root *root = BTRFS_I(file->f_path.dentry->d_inode)->root;
2187
2188         switch (cmd) {
2189         case BTRFS_IOC_SNAP_CREATE:
2190                 return btrfs_ioctl_snap_create(root, (void __user *)arg);
2191         case BTRFS_IOC_DEFRAG:
2192                 return btrfs_ioctl_defrag(file);
2193         }
2194
2195         return -ENOTTY;
2196 }
2197
2198 /*
2199  * Called inside transaction, so use GFP_NOFS
2200  */
2201 struct inode *btrfs_alloc_inode(struct super_block *sb)
2202 {
2203         struct btrfs_inode *ei;
2204
2205         ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
2206         if (!ei)
2207                 return NULL;
2208         ei->last_trans = 0;
2209         return &ei->vfs_inode;
2210 }
2211
2212 void btrfs_destroy_inode(struct inode *inode)
2213 {
2214         WARN_ON(!list_empty(&inode->i_dentry));
2215         WARN_ON(inode->i_data.nrpages);
2216
2217         kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
2218 }
2219
2220 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
2221 static void init_once(struct kmem_cache * cachep, void *foo)
2222 #else
2223 static void init_once(void * foo, struct kmem_cache * cachep,
2224                       unsigned long flags)
2225 #endif
2226 {
2227         struct btrfs_inode *ei = (struct btrfs_inode *) foo;
2228
2229         inode_init_once(&ei->vfs_inode);
2230 }
2231
2232 void btrfs_destroy_cachep(void)
2233 {
2234         if (btrfs_inode_cachep)
2235                 kmem_cache_destroy(btrfs_inode_cachep);
2236         if (btrfs_trans_handle_cachep)
2237                 kmem_cache_destroy(btrfs_trans_handle_cachep);
2238         if (btrfs_transaction_cachep)
2239                 kmem_cache_destroy(btrfs_transaction_cachep);
2240         if (btrfs_bit_radix_cachep)
2241                 kmem_cache_destroy(btrfs_bit_radix_cachep);
2242         if (btrfs_path_cachep)
2243                 kmem_cache_destroy(btrfs_path_cachep);
2244 }
2245
2246 struct kmem_cache *btrfs_cache_create(const char *name, size_t size,
2247                                        unsigned long extra_flags,
2248 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
2249                                        void (*ctor)(struct kmem_cache *, void *)
2250 #else
2251                                        void (*ctor)(void *, struct kmem_cache *,
2252                                                     unsigned long)
2253 #endif
2254                                      )
2255 {
2256         return kmem_cache_create(name, size, 0, (SLAB_RECLAIM_ACCOUNT |
2257                                  SLAB_MEM_SPREAD | extra_flags), ctor
2258 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
2259                                  ,NULL
2260 #endif
2261                                 );
2262 }
2263
2264 int btrfs_init_cachep(void)
2265 {
2266         btrfs_inode_cachep = btrfs_cache_create("btrfs_inode_cache",
2267                                           sizeof(struct btrfs_inode),
2268                                           0, init_once);
2269         if (!btrfs_inode_cachep)
2270                 goto fail;
2271         btrfs_trans_handle_cachep =
2272                         btrfs_cache_create("btrfs_trans_handle_cache",
2273                                            sizeof(struct btrfs_trans_handle),
2274                                            0, NULL);
2275         if (!btrfs_trans_handle_cachep)
2276                 goto fail;
2277         btrfs_transaction_cachep = btrfs_cache_create("btrfs_transaction_cache",
2278                                              sizeof(struct btrfs_transaction),
2279                                              0, NULL);
2280         if (!btrfs_transaction_cachep)
2281                 goto fail;
2282         btrfs_path_cachep = btrfs_cache_create("btrfs_path_cache",
2283                                          sizeof(struct btrfs_path),
2284                                          0, NULL);
2285         if (!btrfs_path_cachep)
2286                 goto fail;
2287         btrfs_bit_radix_cachep = btrfs_cache_create("btrfs_radix", 256,
2288                                               SLAB_DESTROY_BY_RCU, NULL);
2289         if (!btrfs_bit_radix_cachep)
2290                 goto fail;
2291         return 0;
2292 fail:
2293         btrfs_destroy_cachep();
2294         return -ENOMEM;
2295 }
2296
2297 static int btrfs_getattr(struct vfsmount *mnt,
2298                          struct dentry *dentry, struct kstat *stat)
2299 {
2300         struct inode *inode = dentry->d_inode;
2301         generic_fillattr(inode, stat);
2302         stat->blksize = 256 * 1024;
2303         return 0;
2304 }
2305
2306 static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
2307                            struct inode * new_dir,struct dentry *new_dentry)
2308 {
2309         struct btrfs_trans_handle *trans;
2310         struct btrfs_root *root = BTRFS_I(old_dir)->root;
2311         struct inode *new_inode = new_dentry->d_inode;
2312         struct inode *old_inode = old_dentry->d_inode;
2313         struct timespec ctime = CURRENT_TIME;
2314         struct btrfs_path *path;
2315         struct btrfs_dir_item *di;
2316         int ret;
2317
2318         if (S_ISDIR(old_inode->i_mode) && new_inode &&
2319             new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
2320                 return -ENOTEMPTY;
2321         }
2322
2323         mutex_lock(&root->fs_info->fs_mutex);
2324         trans = btrfs_start_transaction(root, 1);
2325
2326         btrfs_set_trans_block_group(trans, new_dir);
2327         path = btrfs_alloc_path();
2328         if (!path) {
2329                 ret = -ENOMEM;
2330                 goto out_fail;
2331         }
2332
2333         old_dentry->d_inode->i_nlink++;
2334         old_dir->i_ctime = old_dir->i_mtime = ctime;
2335         new_dir->i_ctime = new_dir->i_mtime = ctime;
2336         old_inode->i_ctime = ctime;
2337
2338         if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
2339                 struct btrfs_key *location = &BTRFS_I(new_dir)->location;
2340                 struct btrfs_key old_parent_key;
2341                 di = btrfs_lookup_dir_item(trans, root, path, old_inode->i_ino,
2342                                            "..", 2, -1);
2343                 if (IS_ERR(di)) {
2344                         ret = PTR_ERR(di);
2345                         goto out_fail;
2346                 }
2347                 if (!di) {
2348                         ret = -ENOENT;
2349                         goto out_fail;
2350                 }
2351                 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &old_parent_key);
2352                 ret = btrfs_del_item(trans, root, path);
2353                 if (ret) {
2354                         goto out_fail;
2355                 }
2356                 btrfs_release_path(root, path);
2357
2358                 di = btrfs_lookup_dir_index_item(trans, root, path,
2359                                                  old_inode->i_ino,
2360                                                  old_parent_key.objectid,
2361                                                  "..", 2, -1);
2362                 if (IS_ERR(di)) {
2363                         ret = PTR_ERR(di);
2364                         goto out_fail;
2365                 }
2366                 if (!di) {
2367                         ret = -ENOENT;
2368                         goto out_fail;
2369                 }
2370                 ret = btrfs_del_item(trans, root, path);
2371                 if (ret) {
2372                         goto out_fail;
2373                 }
2374                 btrfs_release_path(root, path);
2375
2376                 ret = btrfs_insert_dir_item(trans, root, "..", 2,
2377                                             old_inode->i_ino, location,
2378                                             BTRFS_FT_DIR);
2379                 if (ret)
2380                         goto out_fail;
2381         }
2382
2383
2384         ret = btrfs_unlink_trans(trans, root, old_dir, old_dentry);
2385         if (ret)
2386                 goto out_fail;
2387
2388         if (new_inode) {
2389                 new_inode->i_ctime = CURRENT_TIME;
2390                 ret = btrfs_unlink_trans(trans, root, new_dir, new_dentry);
2391                 if (ret)
2392                         goto out_fail;
2393         }
2394         ret = btrfs_add_link(trans, new_dentry, old_inode);
2395         if (ret)
2396                 goto out_fail;
2397
2398 out_fail:
2399         btrfs_free_path(path);
2400         btrfs_end_transaction(trans, root);
2401         mutex_unlock(&root->fs_info->fs_mutex);
2402         return ret;
2403 }
2404
2405 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
2406                          const char *symname)
2407 {
2408         struct btrfs_trans_handle *trans;
2409         struct btrfs_root *root = BTRFS_I(dir)->root;
2410         struct btrfs_path *path;
2411         struct btrfs_key key;
2412         struct inode *inode;
2413         int err;
2414         int drop_inode = 0;
2415         u64 objectid;
2416         int name_len;
2417         int datasize;
2418         unsigned long ptr;
2419         struct btrfs_file_extent_item *ei;
2420         struct extent_buffer *leaf;
2421         unsigned long nr;
2422
2423         name_len = strlen(symname) + 1;
2424         if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
2425                 return -ENAMETOOLONG;
2426         mutex_lock(&root->fs_info->fs_mutex);
2427         trans = btrfs_start_transaction(root, 1);
2428         btrfs_set_trans_block_group(trans, dir);
2429
2430         err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2431         if (err) {
2432                 err = -ENOSPC;
2433                 goto out_unlock;
2434         }
2435
2436         inode = btrfs_new_inode(trans, root, objectid,
2437                                 BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO);
2438         err = PTR_ERR(inode);
2439         if (IS_ERR(inode))
2440                 goto out_unlock;
2441
2442         btrfs_set_trans_block_group(trans, inode);
2443         err = btrfs_add_nondir(trans, dentry, inode);
2444         if (err)
2445                 drop_inode = 1;
2446         else {
2447                 inode->i_mapping->a_ops = &btrfs_aops;
2448                 inode->i_fop = &btrfs_file_operations;
2449                 inode->i_op = &btrfs_file_inode_operations;
2450                 extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
2451                                      inode->i_mapping, GFP_NOFS);
2452                 BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
2453         }
2454         dir->i_sb->s_dirt = 1;
2455         btrfs_update_inode_block_group(trans, inode);
2456         btrfs_update_inode_block_group(trans, dir);
2457         if (drop_inode)
2458                 goto out_unlock;
2459
2460         path = btrfs_alloc_path();
2461         BUG_ON(!path);
2462         key.objectid = inode->i_ino;
2463         key.offset = 0;
2464         btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
2465         datasize = btrfs_file_extent_calc_inline_size(name_len);
2466         err = btrfs_insert_empty_item(trans, root, path, &key,
2467                                       datasize);
2468         if (err) {
2469                 drop_inode = 1;
2470                 goto out_unlock;
2471         }
2472         leaf = path->nodes[0];
2473         ei = btrfs_item_ptr(leaf, path->slots[0],
2474                             struct btrfs_file_extent_item);
2475         btrfs_set_file_extent_generation(leaf, ei, trans->transid);
2476         btrfs_set_file_extent_type(leaf, ei,
2477                                    BTRFS_FILE_EXTENT_INLINE);
2478         ptr = btrfs_file_extent_inline_start(ei);
2479         write_extent_buffer(leaf, symname, ptr, name_len);
2480         btrfs_mark_buffer_dirty(leaf);
2481         btrfs_free_path(path);
2482
2483         inode->i_op = &btrfs_symlink_inode_operations;
2484         inode->i_mapping->a_ops = &btrfs_symlink_aops;
2485         inode->i_size = name_len - 1;
2486         err = btrfs_update_inode(trans, root, inode);
2487         if (err)
2488                 drop_inode = 1;
2489
2490 out_unlock:
2491         nr = trans->blocks_used;
2492         btrfs_end_transaction(trans, root);
2493         mutex_unlock(&root->fs_info->fs_mutex);
2494         if (drop_inode) {
2495                 inode_dec_link_count(inode);
2496                 iput(inode);
2497         }
2498         btrfs_btree_balance_dirty(root, nr);
2499         return err;
2500 }
2501
2502 static struct inode_operations btrfs_dir_inode_operations = {
2503         .lookup         = btrfs_lookup,
2504         .create         = btrfs_create,
2505         .unlink         = btrfs_unlink,
2506         .link           = btrfs_link,
2507         .mkdir          = btrfs_mkdir,
2508         .rmdir          = btrfs_rmdir,
2509         .rename         = btrfs_rename,
2510         .symlink        = btrfs_symlink,
2511         .setattr        = btrfs_setattr,
2512         .mknod          = btrfs_mknod,
2513 };
2514
2515 static struct inode_operations btrfs_dir_ro_inode_operations = {
2516         .lookup         = btrfs_lookup,
2517 };
2518
2519 static struct file_operations btrfs_dir_file_operations = {
2520         .llseek         = generic_file_llseek,
2521         .read           = generic_read_dir,
2522         .readdir        = btrfs_readdir,
2523         .unlocked_ioctl = btrfs_ioctl,
2524 #ifdef CONFIG_COMPAT
2525         .compat_ioctl   = btrfs_ioctl,
2526 #endif
2527 };
2528
2529 static struct extent_map_ops btrfs_extent_map_ops = {
2530         .fill_delalloc = run_delalloc_range,
2531         .writepage_io_hook = btrfs_writepage_io_hook,
2532         .readpage_io_hook = btrfs_readpage_io_hook,
2533         .readpage_end_io_hook = btrfs_readpage_end_io_hook,
2534 };
2535
2536 static struct address_space_operations btrfs_aops = {
2537         .readpage       = btrfs_readpage,
2538         .writepage      = btrfs_writepage,
2539         .writepages     = btrfs_writepages,
2540         .sync_page      = block_sync_page,
2541         .prepare_write  = btrfs_prepare_write,
2542         .commit_write   = btrfs_commit_write,
2543         .bmap           = btrfs_bmap,
2544         .invalidatepage = btrfs_invalidatepage,
2545         .releasepage    = btrfs_releasepage,
2546         .set_page_dirty = __set_page_dirty_nobuffers,
2547 };
2548
2549 static struct address_space_operations btrfs_symlink_aops = {
2550         .readpage       = btrfs_readpage,
2551         .writepage      = btrfs_writepage,
2552         .invalidatepage = btrfs_invalidatepage,
2553         .releasepage    = btrfs_releasepage,
2554 };
2555
2556 static struct inode_operations btrfs_file_inode_operations = {
2557         .truncate       = btrfs_truncate,
2558         .getattr        = btrfs_getattr,
2559         .setattr        = btrfs_setattr,
2560 };
2561
2562 static struct inode_operations btrfs_special_inode_operations = {
2563         .getattr        = btrfs_getattr,
2564         .setattr        = btrfs_setattr,
2565 };
2566
2567 static struct inode_operations btrfs_symlink_inode_operations = {
2568         .readlink       = generic_readlink,
2569         .follow_link    = page_follow_link_light,
2570         .put_link       = page_put_link,
2571 };