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1 #include <linux/module.h>
2 #include <linux/buffer_head.h>
3 #include <linux/fs.h>
4 #include <linux/pagemap.h>
5 #include <linux/highmem.h>
6 #include <linux/time.h>
7 #include <linux/init.h>
8 #include <linux/string.h>
9 #include <linux/smp_lock.h>
10 #include <linux/backing-dev.h>
11 #include <linux/mpage.h>
12 #include <linux/swap.h>
13 #include <linux/writeback.h>
14 #include "ctree.h"
15 #include "disk-io.h"
16 #include "transaction.h"
17 #include "btrfs_inode.h"
18
19 #define BTRFS_SUPER_MAGIC 0x9123682E
20
21 static struct inode_operations btrfs_dir_inode_operations;
22 static struct super_operations btrfs_super_ops;
23 static struct file_operations btrfs_dir_file_operations;
24 static struct inode_operations btrfs_file_inode_operations;
25 static struct address_space_operations btrfs_aops;
26 static struct file_operations btrfs_file_operations;
27
28 static int check_inode(struct inode *inode)
29 {
30 struct btrfs_inode *ei = BTRFS_I(inode);
31 WARN_ON(ei->magic != 0xDEADBEEF);
32 WARN_ON(ei->magic2 != 0xDEADBEAF);
33 return 0;
34 }
35
36 static void btrfs_read_locked_inode(struct inode *inode)
37 {
38 struct btrfs_path *path;
39 struct btrfs_inode_item *inode_item;
40 struct btrfs_root *root = btrfs_sb(inode->i_sb);
41 int ret;
42
43 path = btrfs_alloc_path();
44 BUG_ON(!path);
45 btrfs_init_path(path);
46 mutex_lock(&root->fs_info->fs_mutex);
47
48 check_inode(inode);
49 ret = btrfs_lookup_inode(NULL, root, path, inode->i_ino, 0);
50 if (ret) {
51 btrfs_release_path(root, path);
52 btrfs_free_path(path);
53 mutex_unlock(&root->fs_info->fs_mutex);
54 make_bad_inode(inode);
55 return;
56 }
57 check_inode(inode);
58 inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
59 path->slots[0],
60 struct btrfs_inode_item);
61
62 inode->i_mode = btrfs_inode_mode(inode_item);
63 inode->i_nlink = btrfs_inode_nlink(inode_item);
64 inode->i_uid = btrfs_inode_uid(inode_item);
65 inode->i_gid = btrfs_inode_gid(inode_item);
66 inode->i_size = btrfs_inode_size(inode_item);
67 inode->i_atime.tv_sec = btrfs_timespec_sec(&inode_item->atime);
68 inode->i_atime.tv_nsec = btrfs_timespec_nsec(&inode_item->atime);
69 inode->i_mtime.tv_sec = btrfs_timespec_sec(&inode_item->mtime);
70 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(&inode_item->mtime);
71 inode->i_ctime.tv_sec = btrfs_timespec_sec(&inode_item->ctime);
72 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(&inode_item->ctime);
73 inode->i_blocks = btrfs_inode_nblocks(inode_item);
74 inode->i_generation = btrfs_inode_generation(inode_item);
75
76 btrfs_release_path(root, path);
77 btrfs_free_path(path);
78 inode_item = NULL;
79
80 mutex_unlock(&root->fs_info->fs_mutex);
81 check_inode(inode);
82 switch (inode->i_mode & S_IFMT) {
83 #if 0
84 default:
85 init_special_inode(inode, inode->i_mode,
86 btrfs_inode_rdev(inode_item));
87 break;
88 #endif
89 case S_IFREG:
90 inode->i_mapping->a_ops = &btrfs_aops;
91 inode->i_fop = &btrfs_file_operations;
92 inode->i_op = &btrfs_file_inode_operations;
93 break;
94 case S_IFDIR:
95 inode->i_op = &btrfs_dir_inode_operations;
96 inode->i_fop = &btrfs_dir_file_operations;
97 break;
98 case S_IFLNK:
99 // inode->i_op = &page_symlink_inode_operations;
100 break;
101 }
102 check_inode(inode);
103 return;
104 }
105
106 static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
107 struct btrfs_root *root,
108 struct inode *dir,
109 struct dentry *dentry)
110 {
111 struct btrfs_path *path;
112 const char *name = dentry->d_name.name;
113 int name_len = dentry->d_name.len;
114 int ret;
115 u64 objectid;
116 struct btrfs_dir_item *di;
117
118 path = btrfs_alloc_path();
119 BUG_ON(!path);
120 btrfs_init_path(path);
121 ret = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
122 name, name_len, -1);
123 if (ret < 0)
124 goto err;
125 if (ret > 0) {
126 ret = -ENOENT;
127 goto err;
128 }
129 di = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
130 struct btrfs_dir_item);
131 objectid = btrfs_dir_objectid(di);
132
133 ret = btrfs_del_item(trans, root, path);
134 BUG_ON(ret);
135
136 btrfs_release_path(root, path);
137 ret = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
138 objectid, -1);
139 BUG_ON(ret);
140 ret = btrfs_del_item(trans, root, path);
141 BUG_ON(ret);
142 dentry->d_inode->i_ctime = dir->i_ctime;
143 err:
144 btrfs_release_path(root, path);
145 btrfs_free_path(path);
146 if (ret == 0) {
147 inode_dec_link_count(dentry->d_inode);
148 dir->i_size -= name_len * 2;
149 mark_inode_dirty(dir);
150 }
151 return ret;
152 }
153
154 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
155 {
156 struct btrfs_root *root;
157 struct btrfs_trans_handle *trans;
158 int ret;
159
160 root = btrfs_sb(dir->i_sb);
161 mutex_lock(&root->fs_info->fs_mutex);
162 trans = btrfs_start_transaction(root, 1);
163 ret = btrfs_unlink_trans(trans, root, dir, dentry);
164 btrfs_end_transaction(trans, root);
165 mutex_unlock(&root->fs_info->fs_mutex);
166 return ret;
167 }
168
169 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
170 {
171 struct inode *inode = dentry->d_inode;
172 int err;
173 int ret;
174 struct btrfs_root *root = btrfs_sb(dir->i_sb);
175 struct btrfs_path *path;
176 struct btrfs_key key;
177 struct btrfs_trans_handle *trans;
178 struct btrfs_key found_key;
179 int found_type;
180 struct btrfs_leaf *leaf;
181 char *goodnames = "..";
182
183 path = btrfs_alloc_path();
184 BUG_ON(!path);
185 btrfs_init_path(path);
186 mutex_lock(&root->fs_info->fs_mutex);
187 trans = btrfs_start_transaction(root, 1);
188 key.objectid = inode->i_ino;
189 key.offset = (u64)-1;
190 key.flags = (u32)-1;
191 while(1) {
192 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
193 if (ret < 0) {
194 err = ret;
195 goto out;
196 }
197 BUG_ON(ret == 0);
198 if (path->slots[0] == 0) {
199 err = -ENOENT;
200 goto out;
201 }
202 path->slots[0]--;
203 leaf = btrfs_buffer_leaf(path->nodes[0]);
204 btrfs_disk_key_to_cpu(&found_key,
205 &leaf->items[path->slots[0]].key);
206 found_type = btrfs_key_type(&found_key);
207 if (found_key.objectid != inode->i_ino) {
208 err = -ENOENT;
209 goto out;
210 }
211 if ((found_type != BTRFS_DIR_ITEM_KEY &&
212 found_type != BTRFS_DIR_INDEX_KEY) ||
213 (!btrfs_match_dir_item_name(root, path, goodnames, 2) &&
214 !btrfs_match_dir_item_name(root, path, goodnames, 1))) {
215 err = -ENOTEMPTY;
216 goto out;
217 }
218 ret = btrfs_del_item(trans, root, path);
219 BUG_ON(ret);
220
221 if (found_type == BTRFS_DIR_ITEM_KEY && found_key.offset == 1)
222 break;
223 btrfs_release_path(root, path);
224 }
225 ret = 0;
226 btrfs_release_path(root, path);
227
228 /* now the directory is empty */
229 err = btrfs_unlink_trans(trans, root, dir, dentry);
230 if (!err) {
231 inode->i_size = 0;
232 }
233 out:
234 btrfs_release_path(root, path);
235 btrfs_free_path(path);
236 mutex_unlock(&root->fs_info->fs_mutex);
237 ret = btrfs_end_transaction(trans, root);
238 if (ret && !err)
239 err = ret;
240 return err;
241 }
242
243 static int btrfs_free_inode(struct btrfs_trans_handle *trans,
244 struct btrfs_root *root,
245 struct inode *inode)
246 {
247 u64 objectid = inode->i_ino;
248 struct btrfs_path *path;
249 struct btrfs_inode_map_item *map;
250 struct btrfs_key stat_data_key;
251 int ret;
252
253 clear_inode(inode);
254
255 path = btrfs_alloc_path();
256 BUG_ON(!path);
257 btrfs_init_path(path);
258 ret = btrfs_lookup_inode_map(trans, root, path, objectid, -1);
259 if (ret) {
260 if (ret > 0)
261 ret = -ENOENT;
262 goto error;
263 }
264 map = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
265 struct btrfs_inode_map_item);
266 btrfs_disk_key_to_cpu(&stat_data_key, &map->key);
267 ret = btrfs_del_item(trans, root->fs_info->inode_root, path);
268 BUG_ON(ret);
269 btrfs_release_path(root, path);
270
271 ret = btrfs_lookup_inode(trans, root, path, objectid, -1);
272 BUG_ON(ret);
273 ret = btrfs_del_item(trans, root, path);
274 BUG_ON(ret);
275 error:
276 btrfs_release_path(root, path);
277 btrfs_free_path(path);
278 return ret;
279 }
280
281 static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
282 struct btrfs_root *root,
283 struct inode *inode)
284 {
285 int ret;
286 struct btrfs_path *path;
287 struct btrfs_key key;
288 struct btrfs_disk_key *found_key;
289 struct btrfs_leaf *leaf;
290 struct btrfs_file_extent_item *fi = NULL;
291 u64 extent_start = 0;
292 u64 extent_num_blocks = 0;
293 int found_extent;
294
295 path = btrfs_alloc_path();
296 BUG_ON(!path);
297 /* FIXME, add redo link to tree so we don't leak on crash */
298 key.objectid = inode->i_ino;
299 key.offset = (u64)-1;
300 key.flags = 0;
301 /*
302 * use BTRFS_CSUM_ITEM_KEY because it is larger than inline keys
303 * or extent data
304 */
305 btrfs_set_key_type(&key, BTRFS_CSUM_ITEM_KEY);
306 while(1) {
307 btrfs_init_path(path);
308 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
309 if (ret < 0) {
310 goto error;
311 }
312 if (ret > 0) {
313 BUG_ON(path->slots[0] == 0);
314 path->slots[0]--;
315 }
316 leaf = btrfs_buffer_leaf(path->nodes[0]);
317 found_key = &leaf->items[path->slots[0]].key;
318 if (btrfs_disk_key_objectid(found_key) != inode->i_ino)
319 break;
320 if (btrfs_disk_key_type(found_key) != BTRFS_CSUM_ITEM_KEY &&
321 btrfs_disk_key_type(found_key) != BTRFS_INLINE_DATA_KEY &&
322 btrfs_disk_key_type(found_key) != BTRFS_EXTENT_DATA_KEY)
323 break;
324 if (btrfs_disk_key_offset(found_key) < inode->i_size)
325 break;
326 if (btrfs_disk_key_type(found_key) == BTRFS_EXTENT_DATA_KEY) {
327 fi = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
328 path->slots[0],
329 struct btrfs_file_extent_item);
330 extent_start = btrfs_file_extent_disk_blocknr(fi);
331 extent_num_blocks =
332 btrfs_file_extent_disk_num_blocks(fi);
333 inode->i_blocks -=
334 btrfs_file_extent_num_blocks(fi) >> 9;
335 found_extent = 1;
336 } else {
337 found_extent = 0;
338 }
339 ret = btrfs_del_item(trans, root, path);
340 BUG_ON(ret);
341 btrfs_release_path(root, path);
342 if (found_extent) {
343 ret = btrfs_free_extent(trans, root, extent_start,
344 extent_num_blocks, 0);
345 BUG_ON(ret);
346 }
347 }
348 ret = 0;
349 error:
350 btrfs_release_path(root, path);
351 btrfs_free_path(path);
352 return ret;
353 }
354
355 static void btrfs_delete_inode(struct inode *inode)
356 {
357 struct btrfs_trans_handle *trans;
358 struct btrfs_root *root = btrfs_sb(inode->i_sb);
359 int ret;
360
361 truncate_inode_pages(&inode->i_data, 0);
362 if (is_bad_inode(inode)) {
363 goto no_delete;
364 }
365 inode->i_size = 0;
366 mutex_lock(&root->fs_info->fs_mutex);
367 trans = btrfs_start_transaction(root, 1);
368 if (S_ISREG(inode->i_mode)) {
369 ret = btrfs_truncate_in_trans(trans, root, inode);
370 BUG_ON(ret);
371 }
372 btrfs_free_inode(trans, root, inode);
373 btrfs_end_transaction(trans, root);
374 mutex_unlock(&root->fs_info->fs_mutex);
375 return;
376 no_delete:
377 clear_inode(inode);
378 }
379
380 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
381 ino_t *ino)
382 {
383 const char *name = dentry->d_name.name;
384 int namelen = dentry->d_name.len;
385 struct btrfs_dir_item *di;
386 struct btrfs_path *path;
387 struct btrfs_root *root = btrfs_sb(dir->i_sb);
388 int ret;
389
390 path = btrfs_alloc_path();
391 BUG_ON(!path);
392 btrfs_init_path(path);
393 ret = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
394 namelen, 0);
395 if (ret || !btrfs_match_dir_item_name(root, path, name, namelen)) {
396 *ino = 0;
397 ret = 0;
398 goto out;
399 }
400 di = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
401 struct btrfs_dir_item);
402 *ino = btrfs_dir_objectid(di);
403 out:
404 btrfs_release_path(root, path);
405 btrfs_free_path(path);
406 check_inode(dir);
407 return ret;
408 }
409
410 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
411 struct nameidata *nd)
412 {
413 struct inode * inode;
414 struct btrfs_root *root = btrfs_sb(dir->i_sb);
415 ino_t ino;
416 int ret;
417
418 if (dentry->d_name.len > BTRFS_NAME_LEN)
419 return ERR_PTR(-ENAMETOOLONG);
420 mutex_lock(&root->fs_info->fs_mutex);
421 ret = btrfs_inode_by_name(dir, dentry, &ino);
422 mutex_unlock(&root->fs_info->fs_mutex);
423 if (ret < 0)
424 return ERR_PTR(ret);
425 inode = NULL;
426 if (ino) {
427 inode = iget(dir->i_sb, ino);
428 if (!inode)
429 return ERR_PTR(-EACCES);
430 check_inode(inode);
431 }
432 check_inode(dir);
433 return d_splice_alias(inode, dentry);
434 }
435
436 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
437 {
438 struct inode *inode = filp->f_path.dentry->d_inode;
439 struct btrfs_root *root = btrfs_sb(inode->i_sb);
440 struct btrfs_item *item;
441 struct btrfs_dir_item *di;
442 struct btrfs_key key;
443 struct btrfs_path *path;
444 int ret;
445 u32 nritems;
446 struct btrfs_leaf *leaf;
447 int slot;
448 int advance;
449 unsigned char d_type = DT_UNKNOWN;
450 int over = 0;
451
452 mutex_lock(&root->fs_info->fs_mutex);
453 key.objectid = inode->i_ino;
454 key.flags = 0;
455 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
456 key.offset = filp->f_pos;
457 path = btrfs_alloc_path();
458 btrfs_init_path(path);
459 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
460 if (ret < 0) {
461 goto err;
462 }
463 advance = 0;
464 while(1) {
465 leaf = btrfs_buffer_leaf(path->nodes[0]);
466 nritems = btrfs_header_nritems(&leaf->header);
467 slot = path->slots[0];
468 if (advance || slot >= nritems) {
469 if (slot >= nritems -1) {
470 ret = btrfs_next_leaf(root, path);
471 if (ret)
472 break;
473 leaf = btrfs_buffer_leaf(path->nodes[0]);
474 nritems = btrfs_header_nritems(&leaf->header);
475 slot = path->slots[0];
476 } else {
477 slot++;
478 path->slots[0]++;
479 }
480 }
481 advance = 1;
482 item = leaf->items + slot;
483 if (btrfs_disk_key_objectid(&item->key) != key.objectid)
484 break;
485 if (btrfs_disk_key_offset(&item->key) >
486 root->fs_info->highest_inode)
487 break;
488 if (btrfs_disk_key_type(&item->key) != BTRFS_DIR_INDEX_KEY)
489 continue;
490 if (btrfs_disk_key_offset(&item->key) < filp->f_pos)
491 continue;
492 filp->f_pos = btrfs_disk_key_offset(&item->key);
493 advance = 1;
494 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
495 over = filldir(dirent, (const char *)(di + 1),
496 btrfs_dir_name_len(di),
497 btrfs_disk_key_offset(&item->key),
498 btrfs_dir_objectid(di), d_type);
499 if (over)
500 goto nopos;
501 }
502 filp->f_pos++;
503 nopos:
504 ret = 0;
505 err:
506 btrfs_release_path(root, path);
507 btrfs_free_path(path);
508 mutex_unlock(&root->fs_info->fs_mutex);
509 return ret;
510 }
511
512 static void btrfs_put_super (struct super_block * sb)
513 {
514 struct btrfs_root *root = btrfs_sb(sb);
515 int ret;
516
517 ret = close_ctree(root);
518 if (ret) {
519 printk("close ctree returns %d\n", ret);
520 }
521 sb->s_fs_info = NULL;
522 }
523
524 static int btrfs_fill_super(struct super_block * sb, void * data, int silent)
525 {
526 struct inode * inode;
527 struct dentry * root_dentry;
528 struct btrfs_super_block *disk_super;
529 struct btrfs_root *root;
530
531 sb->s_maxbytes = MAX_LFS_FILESIZE;
532 sb->s_magic = BTRFS_SUPER_MAGIC;
533 sb->s_op = &btrfs_super_ops;
534 sb->s_time_gran = 1;
535
536 root = open_ctree(sb);
537
538 if (!root) {
539 printk("btrfs: open_ctree failed\n");
540 return -EIO;
541 }
542 sb->s_fs_info = root;
543 disk_super = root->fs_info->disk_super;
544 printk("read in super total blocks %Lu root %Lu\n",
545 btrfs_super_total_blocks(disk_super),
546 btrfs_super_root_dir(disk_super));
547
548 inode = iget_locked(sb, btrfs_super_root_dir(disk_super));
549 if (!inode)
550 return -ENOMEM;
551 if (inode->i_state & I_NEW) {
552 btrfs_read_locked_inode(inode);
553 unlock_new_inode(inode);
554 }
555
556 root_dentry = d_alloc_root(inode);
557 if (!root_dentry) {
558 iput(inode);
559 return -ENOMEM;
560 }
561 sb->s_root = root_dentry;
562
563 return 0;
564 }
565
566 static void fill_inode_item(struct btrfs_inode_item *item,
567 struct inode *inode)
568 {
569 btrfs_set_inode_uid(item, inode->i_uid);
570 btrfs_set_inode_gid(item, inode->i_gid);
571 btrfs_set_inode_size(item, inode->i_size);
572 btrfs_set_inode_mode(item, inode->i_mode);
573 btrfs_set_inode_nlink(item, inode->i_nlink);
574 btrfs_set_timespec_sec(&item->atime, inode->i_atime.tv_sec);
575 btrfs_set_timespec_nsec(&item->atime, inode->i_atime.tv_nsec);
576 btrfs_set_timespec_sec(&item->mtime, inode->i_mtime.tv_sec);
577 btrfs_set_timespec_nsec(&item->mtime, inode->i_mtime.tv_nsec);
578 btrfs_set_timespec_sec(&item->ctime, inode->i_ctime.tv_sec);
579 btrfs_set_timespec_nsec(&item->ctime, inode->i_ctime.tv_nsec);
580 btrfs_set_inode_nblocks(item, inode->i_blocks);
581 btrfs_set_inode_generation(item, inode->i_generation);
582 check_inode(inode);
583 }
584
585 static int btrfs_update_inode(struct btrfs_trans_handle *trans,
586 struct btrfs_root *root,
587 struct inode *inode)
588 {
589 struct btrfs_inode_item *inode_item;
590 struct btrfs_path *path;
591 int ret;
592
593 path = btrfs_alloc_path();
594 BUG_ON(!path);
595 btrfs_init_path(path);
596
597 ret = btrfs_lookup_inode(trans, root, path, inode->i_ino, 1);
598 if (ret) {
599 if (ret > 0)
600 ret = -ENOENT;
601 goto failed;
602 }
603
604 inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
605 path->slots[0],
606 struct btrfs_inode_item);
607
608 fill_inode_item(inode_item, inode);
609 btrfs_mark_buffer_dirty(path->nodes[0]);
610 failed:
611 btrfs_release_path(root, path);
612 btrfs_free_path(path);
613 check_inode(inode);
614 return 0;
615 }
616
617 static int btrfs_write_inode(struct inode *inode, int wait)
618 {
619 struct btrfs_root *root = btrfs_sb(inode->i_sb);
620 struct btrfs_trans_handle *trans;
621 int ret;
622
623 mutex_lock(&root->fs_info->fs_mutex);
624 trans = btrfs_start_transaction(root, 1);
625 ret = btrfs_update_inode(trans, root, inode);
626 if (wait)
627 btrfs_commit_transaction(trans, root);
628 else
629 btrfs_end_transaction(trans, root);
630 mutex_unlock(&root->fs_info->fs_mutex);
631 check_inode(inode);
632 return ret;
633 }
634
635 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
636 struct inode *dir, int mode)
637 {
638 struct inode *inode;
639 struct btrfs_inode_item inode_item;
640 struct btrfs_root *root = btrfs_sb(dir->i_sb);
641 struct btrfs_key key;
642 int ret;
643 u64 objectid;
644
645 inode = new_inode(dir->i_sb);
646 if (!inode)
647 return ERR_PTR(-ENOMEM);
648
649 check_inode(inode);
650 ret = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
651 BUG_ON(ret);
652
653 inode->i_uid = current->fsuid;
654 inode->i_gid = current->fsgid;
655 inode->i_mode = mode;
656 inode->i_ino = objectid;
657 inode->i_blocks = 0;
658 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
659 fill_inode_item(&inode_item, inode);
660
661 key.objectid = objectid;
662 key.flags = 0;
663 key.offset = 0;
664 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
665 ret = btrfs_insert_inode_map(trans, root, objectid, &key);
666 BUG_ON(ret);
667
668 ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
669 BUG_ON(ret);
670
671 insert_inode_hash(inode);
672 check_inode(inode);
673 check_inode(dir);
674 return inode;
675 }
676
677 static int btrfs_add_link(struct btrfs_trans_handle *trans,
678 struct dentry *dentry, struct inode *inode)
679 {
680 int ret;
681 ret = btrfs_insert_dir_item(trans, btrfs_sb(inode->i_sb),
682 dentry->d_name.name, dentry->d_name.len,
683 dentry->d_parent->d_inode->i_ino,
684 inode->i_ino, 0);
685 if (ret == 0) {
686 dentry->d_parent->d_inode->i_size += dentry->d_name.len * 2;
687 ret = btrfs_update_inode(trans, btrfs_sb(inode->i_sb),
688 dentry->d_parent->d_inode);
689 }
690 check_inode(inode);
691 check_inode(dentry->d_parent->d_inode);
692 return ret;
693 }
694
695 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
696 struct dentry *dentry, struct inode *inode)
697 {
698 int err = btrfs_add_link(trans, dentry, inode);
699 if (!err) {
700 d_instantiate(dentry, inode);
701 return 0;
702 }
703 if (err > 0)
704 err = -EEXIST;
705 check_inode(inode);
706 return err;
707 }
708
709 static int btrfs_create(struct inode *dir, struct dentry *dentry,
710 int mode, struct nameidata *nd)
711 {
712 struct btrfs_trans_handle *trans;
713 struct btrfs_root *root = btrfs_sb(dir->i_sb);
714 struct inode *inode;
715 int err;
716 int drop_inode = 0;
717
718 mutex_lock(&root->fs_info->fs_mutex);
719 trans = btrfs_start_transaction(root, 1);
720 inode = btrfs_new_inode(trans, dir, mode);
721 err = PTR_ERR(inode);
722 if (IS_ERR(inode))
723 goto out_unlock;
724 // FIXME mark the inode dirty
725 err = btrfs_add_nondir(trans, dentry, inode);
726 if (err)
727 drop_inode = 1;
728 else {
729 inode->i_mapping->a_ops = &btrfs_aops;
730 inode->i_fop = &btrfs_file_operations;
731 inode->i_op = &btrfs_file_inode_operations;
732 }
733 dir->i_sb->s_dirt = 1;
734 out_unlock:
735 btrfs_end_transaction(trans, root);
736 mutex_unlock(&root->fs_info->fs_mutex);
737 check_inode(inode);
738 check_inode(dir);
739
740 if (drop_inode) {
741 inode_dec_link_count(inode);
742 iput(inode);
743 }
744 return err;
745 }
746
747 static int btrfs_make_empty_dir(struct btrfs_trans_handle *trans,
748 struct inode *inode, struct inode *dir)
749 {
750 struct btrfs_root *root = btrfs_sb(inode->i_sb);
751 int ret;
752 char buf[2];
753 buf[0] = '.';
754 buf[1] = '.';
755
756 ret = btrfs_insert_dir_item(trans, root, buf, 1, inode->i_ino,
757 inode->i_ino, 1);
758 if (ret)
759 goto error;
760 ret = btrfs_insert_dir_item(trans, root, buf, 2, inode->i_ino,
761 dir->i_ino, 1);
762 if (ret)
763 goto error;
764 inode->i_size = 6;
765 ret = btrfs_update_inode(trans, root, inode);
766 error:
767 return ret;
768 }
769
770 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
771 {
772 struct inode *inode;
773 struct btrfs_trans_handle *trans;
774 struct btrfs_root *root = btrfs_sb(dir->i_sb);
775 int err = 0;
776 int drop_on_err = 0;
777
778 mutex_lock(&root->fs_info->fs_mutex);
779 trans = btrfs_start_transaction(root, 1);
780 if (IS_ERR(trans)) {
781 err = PTR_ERR(trans);
782 goto out_unlock;
783 }
784 inode = btrfs_new_inode(trans, dir, S_IFDIR | mode);
785 if (IS_ERR(inode)) {
786 err = PTR_ERR(inode);
787 goto out_fail;
788 }
789 drop_on_err = 1;
790 inode->i_op = &btrfs_dir_inode_operations;
791 inode->i_fop = &btrfs_dir_file_operations;
792
793 err = btrfs_make_empty_dir(trans, inode, dir);
794 if (err)
795 goto out_fail;
796 err = btrfs_add_link(trans, dentry, inode);
797 if (err)
798 goto out_fail;
799 d_instantiate(dentry, inode);
800 drop_on_err = 0;
801
802 out_fail:
803 btrfs_end_transaction(trans, root);
804 out_unlock:
805 mutex_unlock(&root->fs_info->fs_mutex);
806 if (drop_on_err)
807 iput(inode);
808 return err;
809 }
810
811 static int btrfs_sync_fs(struct super_block *sb, int wait)
812 {
813 struct btrfs_trans_handle *trans;
814 struct btrfs_root *root;
815 int ret;
816 root = btrfs_sb(sb);
817
818 sb->s_dirt = 0;
819 if (!wait) {
820 filemap_flush(root->fs_info->btree_inode->i_mapping);
821 return 0;
822 }
823 filemap_write_and_wait(root->fs_info->btree_inode->i_mapping);
824 mutex_lock(&root->fs_info->fs_mutex);
825 trans = btrfs_start_transaction(root, 1);
826 ret = btrfs_commit_transaction(trans, root);
827 sb->s_dirt = 0;
828 BUG_ON(ret);
829 printk("btrfs sync_fs\n");
830 mutex_unlock(&root->fs_info->fs_mutex);
831 return 0;
832 }
833
834 #if 0
835 static int btrfs_get_block_inline(struct inode *inode, sector_t iblock,
836 struct buffer_head *result, int create)
837 {
838 struct btrfs_root *root = btrfs_sb(inode->i_sb);
839 struct btrfs_path *path;
840 struct btrfs_key key;
841 struct btrfs_leaf *leaf;
842 int num_bytes = result->b_size;
843 int item_size;
844 int ret;
845 u64 pos;
846 char *ptr;
847 int copy_size;
848 int err = 0;
849 char *safe_ptr;
850 char *data_ptr;
851
852 path = btrfs_alloc_path();
853 BUG_ON(!path);
854
855 WARN_ON(create);
856 if (create) {
857 return 0;
858 }
859 pos = iblock << inode->i_blkbits;
860 key.objectid = inode->i_ino;
861 key.flags = 0;
862 btrfs_set_key_type(&key, BTRFS_INLINE_DATA_KEY);
863 ptr = kmap(result->b_page);
864 safe_ptr = ptr;
865 ptr += (pos & (PAGE_CACHE_SIZE -1));
866 again:
867 key.offset = pos;
868 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
869 if (ret) {
870 if (ret < 0)
871 err = ret;
872 else
873 err = 0;
874 goto out;
875 }
876 leaf = btrfs_buffer_leaf(path->nodes[0]);
877 item_size = btrfs_item_size(leaf->items + path->slots[0]);
878 copy_size = min(num_bytes, item_size);
879 data_ptr = btrfs_item_ptr(leaf, path->slots[0], char);
880 WARN_ON(safe_ptr + PAGE_CACHE_SIZE < ptr + copy_size);
881 memcpy(ptr, data_ptr, copy_size);
882 pos += copy_size;
883 num_bytes -= copy_size;
884 WARN_ON(num_bytes < 0);
885 ptr += copy_size;
886 btrfs_release_path(root, path);
887 if (num_bytes != 0) {
888 if (pos >= i_size_read(inode))
889 memset(ptr, 0, num_bytes);
890 else
891 goto again;
892 }
893 set_buffer_uptodate(result);
894 map_bh(result, inode->i_sb, 0);
895 err = 0;
896 out:
897 btrfs_free_path(path);
898 kunmap(result->b_page);
899 return err;
900 }
901 #endif
902
903 static int btrfs_get_block_lock(struct inode *inode, sector_t iblock,
904 struct buffer_head *result, int create)
905 {
906 int ret;
907 int err = 0;
908 u64 blocknr;
909 u64 extent_start = 0;
910 u64 extent_end = 0;
911 u64 objectid = inode->i_ino;
912 struct btrfs_path *path;
913 struct btrfs_root *root = btrfs_sb(inode->i_sb);
914 struct btrfs_trans_handle *trans = NULL;
915 struct btrfs_file_extent_item *item;
916 struct btrfs_leaf *leaf;
917 struct btrfs_disk_key *found_key;
918
919 path = btrfs_alloc_path();
920 BUG_ON(!path);
921 btrfs_init_path(path);
922 if (create)
923 trans = btrfs_start_transaction(root, 1);
924
925 ret = btrfs_lookup_file_extent(trans, root, path,
926 inode->i_ino,
927 iblock << inode->i_blkbits, 0);
928 if (ret < 0) {
929 err = ret;
930 goto out;
931 }
932
933 if (ret != 0) {
934 if (path->slots[0] == 0) {
935 btrfs_release_path(root, path);
936 goto allocate;
937 }
938 path->slots[0]--;
939 }
940
941 item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
942 struct btrfs_file_extent_item);
943 leaf = btrfs_buffer_leaf(path->nodes[0]);
944 blocknr = btrfs_file_extent_disk_blocknr(item);
945 blocknr += btrfs_file_extent_offset(item);
946
947 /* exact match found, use it */
948 if (ret == 0) {
949 err = 0;
950 map_bh(result, inode->i_sb, blocknr);
951 goto out;
952 }
953
954 /* are we inside the extent that was found? */
955 found_key = &leaf->items[path->slots[0]].key;
956 if (btrfs_disk_key_objectid(found_key) != objectid ||
957 btrfs_disk_key_type(found_key) != BTRFS_EXTENT_DATA_KEY) {
958 extent_end = 0;
959 extent_start = 0;
960 btrfs_release_path(root, path);
961 goto allocate;
962 }
963
964 extent_start = btrfs_disk_key_offset(&leaf->items[path->slots[0]].key);
965 extent_start = extent_start >> inode->i_blkbits;
966 extent_start += btrfs_file_extent_offset(item);
967 extent_end = extent_start + btrfs_file_extent_num_blocks(item);
968 if (iblock >= extent_start && iblock < extent_end) {
969 err = 0;
970 map_bh(result, inode->i_sb, blocknr + iblock - extent_start);
971 goto out;
972 }
973 allocate:
974 /* ok, create a new extent */
975 if (!create) {
976 err = 0;
977 goto out;
978 }
979 ret = btrfs_alloc_file_extent(trans, root, objectid,
980 iblock << inode->i_blkbits,
981 1, extent_end, &blocknr);
982 if (ret) {
983 err = ret;
984 goto out;
985 }
986 inode->i_blocks += inode->i_sb->s_blocksize >> 9;
987 set_buffer_new(result);
988 map_bh(result, inode->i_sb, blocknr);
989
990 out:
991 btrfs_release_path(root, path);
992 btrfs_free_path(path);
993 if (trans)
994 btrfs_end_transaction(trans, root);
995 return err;
996 }
997
998 static int btrfs_get_block(struct inode *inode, sector_t iblock,
999 struct buffer_head *result, int create)
1000 {
1001 int err;
1002 struct btrfs_root *root = btrfs_sb(inode->i_sb);
1003 mutex_lock(&root->fs_info->fs_mutex);
1004 err = btrfs_get_block_lock(inode, iblock, result, create);
1005 // err = btrfs_get_block_inline(inode, iblock, result, create);
1006 mutex_unlock(&root->fs_info->fs_mutex);
1007 return err;
1008 }
1009
1010 static int btrfs_prepare_write(struct file *file, struct page *page,
1011 unsigned from, unsigned to)
1012 {
1013 return nobh_prepare_write(page, from, to, btrfs_get_block);
1014 }
1015 static int btrfs_commit_write(struct file *file, struct page *page,
1016 unsigned from, unsigned to)
1017 {
1018 return nobh_commit_write(file, page, from, to);
1019 }
1020
1021 static void btrfs_write_super(struct super_block *sb)
1022 {
1023 btrfs_sync_fs(sb, 1);
1024 }
1025
1026 static int btrfs_readpage(struct file *file, struct page *page)
1027 {
1028 return mpage_readpage(page, btrfs_get_block);
1029 }
1030
1031 static int btrfs_readpages(struct file *file, struct address_space *mapping,
1032 struct list_head *pages, unsigned nr_pages)
1033 {
1034 return mpage_readpages(mapping, pages, nr_pages, btrfs_get_block);
1035 }
1036
1037 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
1038 {
1039 return nobh_writepage(page, btrfs_get_block, wbc);
1040 }
1041
1042 static void btrfs_truncate(struct inode *inode)
1043 {
1044 struct btrfs_root *root = btrfs_sb(inode->i_sb);
1045 int ret;
1046 struct btrfs_trans_handle *trans;
1047
1048 if (!S_ISREG(inode->i_mode))
1049 return;
1050 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
1051 return;
1052
1053 nobh_truncate_page(inode->i_mapping, inode->i_size);
1054
1055 /* FIXME, add redo link to tree so we don't leak on crash */
1056 mutex_lock(&root->fs_info->fs_mutex);
1057 trans = btrfs_start_transaction(root, 1);
1058 ret = btrfs_truncate_in_trans(trans, root, inode);
1059 BUG_ON(ret);
1060 ret = btrfs_end_transaction(trans, root);
1061 BUG_ON(ret);
1062 mutex_unlock(&root->fs_info->fs_mutex);
1063 mark_inode_dirty(inode);
1064 }
1065
1066 static int btrfs_copy_from_user(loff_t pos, int num_pages, int write_bytes,
1067 struct page **prepared_pages,
1068 const char __user * buf)
1069 {
1070 long page_fault = 0;
1071 int i;
1072 int offset = pos & (PAGE_CACHE_SIZE - 1);
1073
1074 for (i = 0; i < num_pages && write_bytes > 0; i++, offset = 0) {
1075 size_t count = min_t(size_t,
1076 PAGE_CACHE_SIZE - offset, write_bytes);
1077 struct page *page = prepared_pages[i];
1078 fault_in_pages_readable(buf, count);
1079
1080 /* Copy data from userspace to the current page */
1081 kmap(page);
1082 page_fault = __copy_from_user(page_address(page) + offset,
1083 buf, count);
1084 /* Flush processor's dcache for this page */
1085 flush_dcache_page(page);
1086 kunmap(page);
1087 buf += count;
1088 write_bytes -= count;
1089
1090 if (page_fault)
1091 break;
1092 }
1093 return page_fault ? -EFAULT : 0;
1094 }
1095
1096 static void btrfs_drop_pages(struct page **pages, size_t num_pages)
1097 {
1098 size_t i;
1099 for (i = 0; i < num_pages; i++) {
1100 if (!pages[i])
1101 break;
1102 unlock_page(pages[i]);
1103 mark_page_accessed(pages[i]);
1104 page_cache_release(pages[i]);
1105 }
1106 }
1107 static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
1108 struct btrfs_root *root,
1109 struct file *file,
1110 struct page **pages,
1111 size_t num_pages,
1112 loff_t pos,
1113 size_t write_bytes)
1114 {
1115 int i;
1116 int offset;
1117 int err = 0;
1118 int ret;
1119 int this_write;
1120 struct inode *inode = file->f_path.dentry->d_inode;
1121
1122 for (i = 0; i < num_pages; i++) {
1123 offset = pos & (PAGE_CACHE_SIZE -1);
1124 this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
1125 /* FIXME, one block at a time */
1126
1127 mutex_lock(&root->fs_info->fs_mutex);
1128 trans = btrfs_start_transaction(root, 1);
1129 btrfs_csum_file_block(trans, root, inode->i_ino,
1130 pages[i]->index << PAGE_CACHE_SHIFT,
1131 kmap(pages[i]), PAGE_CACHE_SIZE);
1132 kunmap(pages[i]);
1133 SetPageChecked(pages[i]);
1134 ret = btrfs_end_transaction(trans, root);
1135 BUG_ON(ret);
1136 mutex_unlock(&root->fs_info->fs_mutex);
1137
1138 ret = nobh_commit_write(file, pages[i], offset,
1139 offset + this_write);
1140 pos += this_write;
1141 if (ret) {
1142 err = ret;
1143 goto failed;
1144 }
1145 WARN_ON(this_write > write_bytes);
1146 write_bytes -= this_write;
1147 }
1148 failed:
1149 return err;
1150 }
1151
1152 static int prepare_pages(struct btrfs_trans_handle *trans,
1153 struct btrfs_root *root,
1154 struct file *file,
1155 struct page **pages,
1156 size_t num_pages,
1157 loff_t pos,
1158 size_t write_bytes)
1159 {
1160 int i;
1161 unsigned long index = pos >> PAGE_CACHE_SHIFT;
1162 struct inode *inode = file->f_path.dentry->d_inode;
1163 int offset;
1164 int err = 0;
1165 int ret;
1166 int this_write;
1167 loff_t isize = i_size_read(inode);
1168
1169 memset(pages, 0, num_pages * sizeof(struct page *));
1170
1171 for (i = 0; i < num_pages; i++) {
1172 pages[i] = grab_cache_page(inode->i_mapping, index + i);
1173 if (!pages[i]) {
1174 err = -ENOMEM;
1175 goto failed_release;
1176 }
1177 offset = pos & (PAGE_CACHE_SIZE -1);
1178 this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
1179 ret = nobh_prepare_write(pages[i], offset,
1180 offset + this_write,
1181 btrfs_get_block);
1182 pos += this_write;
1183 if (ret) {
1184 err = ret;
1185 goto failed_truncate;
1186 }
1187 WARN_ON(this_write > write_bytes);
1188 write_bytes -= this_write;
1189 }
1190 return 0;
1191
1192 failed_release:
1193 btrfs_drop_pages(pages, num_pages);
1194 return err;
1195
1196 failed_truncate:
1197 btrfs_drop_pages(pages, num_pages);
1198 if (pos > isize)
1199 vmtruncate(inode, isize);
1200 return err;
1201 }
1202
1203 static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
1204 size_t count, loff_t *ppos)
1205 {
1206 loff_t pos;
1207 size_t num_written = 0;
1208 int err = 0;
1209 int ret = 0;
1210 struct inode *inode = file->f_path.dentry->d_inode;
1211 struct btrfs_root *root = btrfs_sb(inode->i_sb);
1212 struct page *pages[1];
1213
1214 if (file->f_flags & O_DIRECT)
1215 return -EINVAL;
1216 pos = *ppos;
1217
1218 vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
1219 current->backing_dev_info = inode->i_mapping->backing_dev_info;
1220 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
1221 if (err)
1222 goto out;
1223 if (count == 0)
1224 goto out;
1225 err = remove_suid(file->f_path.dentry);
1226 if (err)
1227 goto out;
1228 file_update_time(file);
1229 mutex_lock(&inode->i_mutex);
1230 while(count > 0) {
1231 size_t offset = pos & (PAGE_CACHE_SIZE - 1);
1232 size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset);
1233 size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
1234 PAGE_CACHE_SHIFT;
1235 ret = prepare_pages(NULL, root, file, pages, num_pages,
1236 pos, write_bytes);
1237 BUG_ON(ret);
1238 ret = btrfs_copy_from_user(pos, num_pages,
1239 write_bytes, pages, buf);
1240 BUG_ON(ret);
1241
1242 ret = dirty_and_release_pages(NULL, root, file, pages,
1243 num_pages, pos, write_bytes);
1244 BUG_ON(ret);
1245 btrfs_drop_pages(pages, num_pages);
1246
1247 buf += write_bytes;
1248 count -= write_bytes;
1249 pos += write_bytes;
1250 num_written += write_bytes;
1251
1252 balance_dirty_pages_ratelimited(inode->i_mapping);
1253 cond_resched();
1254 }
1255 mutex_unlock(&inode->i_mutex);
1256 out:
1257 *ppos = pos;
1258 current->backing_dev_info = NULL;
1259 return num_written ? num_written : err;
1260 }
1261
1262 #if 0
1263 static ssize_t inline_one_page(struct btrfs_root *root, struct inode *inode,
1264 struct page *page, loff_t pos,
1265 size_t offset, size_t write_bytes)
1266 {
1267 struct btrfs_path *path;
1268 struct btrfs_trans_handle *trans;
1269 struct btrfs_key key;
1270 struct btrfs_leaf *leaf;
1271 struct btrfs_key found_key;
1272 int ret;
1273 size_t copy_size = 0;
1274 char *dst = NULL;
1275 int err = 0;
1276 size_t num_written = 0;
1277
1278 path = btrfs_alloc_path();
1279 BUG_ON(!path);
1280 mutex_lock(&root->fs_info->fs_mutex);
1281 trans = btrfs_start_transaction(root, 1);
1282 key.objectid = inode->i_ino;
1283 key.flags = 0;
1284 btrfs_set_key_type(&key, BTRFS_INLINE_DATA_KEY);
1285
1286 again:
1287 key.offset = pos;
1288 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1289 if (ret < 0) {
1290 err = ret;
1291 goto out;
1292 }
1293 if (ret == 0) {
1294 leaf = btrfs_buffer_leaf(path->nodes[0]);
1295 btrfs_disk_key_to_cpu(&found_key,
1296 &leaf->items[path->slots[0]].key);
1297 copy_size = btrfs_item_size(leaf->items + path->slots[0]);
1298 dst = btrfs_item_ptr(leaf, path->slots[0], char);
1299 copy_size = min(write_bytes, copy_size);
1300 goto copyit;
1301 } else {
1302 int slot = path->slots[0];
1303 if (slot > 0) {
1304 slot--;
1305 }
1306 // FIXME find max key
1307 leaf = btrfs_buffer_leaf(path->nodes[0]);
1308 btrfs_disk_key_to_cpu(&found_key,
1309 &leaf->items[slot].key);
1310 if (found_key.objectid != inode->i_ino)
1311 goto insert;
1312 if (btrfs_key_type(&found_key) != BTRFS_INLINE_DATA_KEY)
1313 goto insert;
1314 copy_size = btrfs_item_size(leaf->items + slot);
1315 if (found_key.offset + copy_size <= pos)
1316 goto insert;
1317 dst = btrfs_item_ptr(leaf, path->slots[0], char);
1318 dst += pos - found_key.offset;
1319 copy_size = copy_size - (pos - found_key.offset);
1320 BUG_ON(copy_size < 0);
1321 copy_size = min(write_bytes, copy_size);
1322 WARN_ON(copy_size == 0);
1323 goto copyit;
1324 }
1325 insert:
1326 btrfs_release_path(root, path);
1327 copy_size = min(write_bytes,
1328 (size_t)BTRFS_LEAF_DATA_SIZE(root) -
1329 sizeof(struct btrfs_item) * 4);
1330 ret = btrfs_insert_empty_item(trans, root, path, &key, copy_size);
1331 BUG_ON(ret);
1332 dst = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
1333 path->slots[0], char);
1334 copyit:
1335 WARN_ON(copy_size == 0);
1336 WARN_ON(dst + copy_size >
1337 btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
1338 path->slots[0], char) +
1339 btrfs_item_size(btrfs_buffer_leaf(path->nodes[0])->items +
1340 path->slots[0]));
1341 btrfs_memcpy(root, path->nodes[0]->b_data, dst,
1342 page_address(page) + offset, copy_size);
1343 mark_buffer_dirty(path->nodes[0]);
1344 btrfs_release_path(root, path);
1345 pos += copy_size;
1346 offset += copy_size;
1347 num_written += copy_size;
1348 write_bytes -= copy_size;
1349 if (write_bytes)
1350 goto again;
1351 out:
1352 btrfs_free_path(path);
1353 ret = btrfs_end_transaction(trans, root);
1354 BUG_ON(ret);
1355 mutex_unlock(&root->fs_info->fs_mutex);
1356 return num_written ? num_written : err;
1357 }
1358
1359 static ssize_t btrfs_file_inline_write(struct file *file,
1360 const char __user *buf,
1361 size_t count, loff_t *ppos)
1362 {
1363 loff_t pos;
1364 size_t num_written = 0;
1365 int err = 0;
1366 int ret = 0;
1367 struct inode *inode = file->f_path.dentry->d_inode;
1368 struct btrfs_root *root = btrfs_sb(inode->i_sb);
1369 unsigned long page_index;
1370
1371 if (file->f_flags & O_DIRECT)
1372 return -EINVAL;
1373 pos = *ppos;
1374
1375 vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
1376 current->backing_dev_info = inode->i_mapping->backing_dev_info;
1377 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
1378 if (err)
1379 goto out;
1380 if (count == 0)
1381 goto out;
1382 err = remove_suid(file->f_path.dentry);
1383 if (err)
1384 goto out;
1385 file_update_time(file);
1386 mutex_lock(&inode->i_mutex);
1387 while(count > 0) {
1388 size_t offset = pos & (PAGE_CACHE_SIZE - 1);
1389 size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset);
1390 struct page *page;
1391
1392 page_index = pos >> PAGE_CACHE_SHIFT;
1393 page = grab_cache_page(inode->i_mapping, page_index);
1394 if (!PageUptodate(page)) {
1395 ret = mpage_readpage(page, btrfs_get_block);
1396 BUG_ON(ret);
1397 lock_page(page);
1398 }
1399 ret = btrfs_copy_from_user(pos, 1,
1400 write_bytes, &page, buf);
1401 BUG_ON(ret);
1402 write_bytes = inline_one_page(root, inode, page, pos,
1403 offset, write_bytes);
1404 SetPageUptodate(page);
1405 if (write_bytes > 0 && pos + write_bytes > inode->i_size) {
1406 i_size_write(inode, pos + write_bytes);
1407 mark_inode_dirty(inode);
1408 }
1409 page_cache_release(page);
1410 unlock_page(page);
1411 if (write_bytes < 0)
1412 goto out_unlock;
1413 buf += write_bytes;
1414 count -= write_bytes;
1415 pos += write_bytes;
1416 num_written += write_bytes;
1417
1418 balance_dirty_pages_ratelimited(inode->i_mapping);
1419 cond_resched();
1420 }
1421 out_unlock:
1422 mutex_unlock(&inode->i_mutex);
1423 out:
1424 *ppos = pos;
1425 current->backing_dev_info = NULL;
1426 return num_written ? num_written : err;
1427 }
1428 #endif
1429
1430 static int btrfs_read_actor(read_descriptor_t *desc, struct page *page,
1431 unsigned long offset, unsigned long size)
1432 {
1433 char *kaddr;
1434 unsigned long left, count = desc->count;
1435
1436 if (size > count)
1437 size = count;
1438
1439 if (!PageChecked(page)) {
1440 /* FIXME, do it per block */
1441 struct btrfs_root *root = btrfs_sb(page->mapping->host->i_sb);
1442 int ret = btrfs_csum_verify_file_block(root,
1443 page->mapping->host->i_ino,
1444 page->index << PAGE_CACHE_SHIFT,
1445 kmap(page), PAGE_CACHE_SIZE);
1446 if (ret) {
1447 printk("failed to verify ino %lu page %lu\n",
1448 page->mapping->host->i_ino,
1449 page->index);
1450 memset(page_address(page), 0, PAGE_CACHE_SIZE);
1451 }
1452 SetPageChecked(page);
1453 kunmap(page);
1454 }
1455 /*
1456 * Faults on the destination of a read are common, so do it before
1457 * taking the kmap.
1458 */
1459 if (!fault_in_pages_writeable(desc->arg.buf, size)) {
1460 kaddr = kmap_atomic(page, KM_USER0);
1461 left = __copy_to_user_inatomic(desc->arg.buf,
1462 kaddr + offset, size);
1463 kunmap_atomic(kaddr, KM_USER0);
1464 if (left == 0)
1465 goto success;
1466 }
1467
1468 /* Do it the slow way */
1469 kaddr = kmap(page);
1470 left = __copy_to_user(desc->arg.buf, kaddr + offset, size);
1471 kunmap(page);
1472
1473 if (left) {
1474 size -= left;
1475 desc->error = -EFAULT;
1476 }
1477 success:
1478 desc->count = count - size;
1479 desc->written += size;
1480 desc->arg.buf += size;
1481 return size;
1482 }
1483
1484 /**
1485 * btrfs_file_aio_read - filesystem read routine
1486 * @iocb: kernel I/O control block
1487 * @iov: io vector request
1488 * @nr_segs: number of segments in the iovec
1489 * @pos: current file position
1490 */
1491 static ssize_t btrfs_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
1492 unsigned long nr_segs, loff_t pos)
1493 {
1494 struct file *filp = iocb->ki_filp;
1495 ssize_t retval;
1496 unsigned long seg;
1497 size_t count;
1498 loff_t *ppos = &iocb->ki_pos;
1499
1500 count = 0;
1501 for (seg = 0; seg < nr_segs; seg++) {
1502 const struct iovec *iv = &iov[seg];
1503
1504 /*
1505 * If any segment has a negative length, or the cumulative
1506 * length ever wraps negative then return -EINVAL.
1507 */
1508 count += iv->iov_len;
1509 if (unlikely((ssize_t)(count|iv->iov_len) < 0))
1510 return -EINVAL;
1511 if (access_ok(VERIFY_WRITE, iv->iov_base, iv->iov_len))
1512 continue;
1513 if (seg == 0)
1514 return -EFAULT;
1515 nr_segs = seg;
1516 count -= iv->iov_len; /* This segment is no good */
1517 break;
1518 }
1519 retval = 0;
1520 if (count) {
1521 for (seg = 0; seg < nr_segs; seg++) {
1522 read_descriptor_t desc;
1523
1524 desc.written = 0;
1525 desc.arg.buf = iov[seg].iov_base;
1526 desc.count = iov[seg].iov_len;
1527 if (desc.count == 0)
1528 continue;
1529 desc.error = 0;
1530 do_generic_file_read(filp, ppos, &desc,
1531 btrfs_read_actor);
1532 retval += desc.written;
1533 if (desc.error) {
1534 retval = retval ?: desc.error;
1535 break;
1536 }
1537 }
1538 }
1539 return retval;
1540 }
1541
1542 static struct kmem_cache *btrfs_inode_cachep;
1543 struct kmem_cache *btrfs_trans_handle_cachep;
1544 struct kmem_cache *btrfs_transaction_cachep;
1545 struct kmem_cache *btrfs_bit_radix_cachep;
1546 struct kmem_cache *btrfs_path_cachep;
1547
1548 /*
1549 * Called inside transaction, so use GFP_NOFS
1550 */
1551 static struct inode *btrfs_alloc_inode(struct super_block *sb)
1552 {
1553 struct btrfs_inode *ei;
1554
1555 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
1556 if (!ei)
1557 return NULL;
1558 ei->magic = 0xDEADBEEF;
1559 ei->magic2 = 0xDEADBEAF;
1560 return &ei->vfs_inode;
1561 }
1562
1563 static void btrfs_destroy_inode(struct inode *inode)
1564 {
1565 struct btrfs_inode *ei = BTRFS_I(inode);
1566 WARN_ON(ei->magic != 0xDEADBEEF);
1567 WARN_ON(ei->magic2 != 0xDEADBEAF);
1568 WARN_ON(!list_empty(&inode->i_dentry));
1569 WARN_ON(inode->i_data.nrpages);
1570
1571 ei->magic = 0;
1572 ei->magic2 = 0;
1573 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
1574 }
1575
1576 static void init_once(void * foo, struct kmem_cache * cachep,
1577 unsigned long flags)
1578 {
1579 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
1580
1581 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
1582 SLAB_CTOR_CONSTRUCTOR) {
1583 inode_init_once(&ei->vfs_inode);
1584 }
1585 }
1586
1587 static int init_inodecache(void)
1588 {
1589 btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache",
1590 sizeof(struct btrfs_inode),
1591 0, (SLAB_RECLAIM_ACCOUNT|
1592 SLAB_MEM_SPREAD),
1593 init_once, NULL);
1594 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache",
1595 sizeof(struct btrfs_trans_handle),
1596 0, (SLAB_RECLAIM_ACCOUNT|
1597 SLAB_MEM_SPREAD),
1598 NULL, NULL);
1599 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache",
1600 sizeof(struct btrfs_transaction),
1601 0, (SLAB_RECLAIM_ACCOUNT|
1602 SLAB_MEM_SPREAD),
1603 NULL, NULL);
1604 btrfs_path_cachep = kmem_cache_create("btrfs_path_cache",
1605 sizeof(struct btrfs_transaction),
1606 0, (SLAB_RECLAIM_ACCOUNT|
1607 SLAB_MEM_SPREAD),
1608 NULL, NULL);
1609 btrfs_bit_radix_cachep = kmem_cache_create("btrfs_radix",
1610 256,
1611 0, (SLAB_RECLAIM_ACCOUNT|
1612 SLAB_MEM_SPREAD |
1613 SLAB_DESTROY_BY_RCU),
1614 NULL, NULL);
1615 if (btrfs_inode_cachep == NULL || btrfs_trans_handle_cachep == NULL ||
1616 btrfs_transaction_cachep == NULL || btrfs_bit_radix_cachep == NULL)
1617 return -ENOMEM;
1618 return 0;
1619 }
1620
1621 static void destroy_inodecache(void)
1622 {
1623 kmem_cache_destroy(btrfs_inode_cachep);
1624 kmem_cache_destroy(btrfs_trans_handle_cachep);
1625 kmem_cache_destroy(btrfs_transaction_cachep);
1626 kmem_cache_destroy(btrfs_bit_radix_cachep);
1627 kmem_cache_destroy(btrfs_path_cachep);
1628 }
1629
1630 static int btrfs_get_sb(struct file_system_type *fs_type,
1631 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
1632 {
1633 return get_sb_bdev(fs_type, flags, dev_name, data,
1634 btrfs_fill_super, mnt);
1635 }
1636
1637 static struct file_system_type btrfs_fs_type = {
1638 .owner = THIS_MODULE,
1639 .name = "btrfs",
1640 .get_sb = btrfs_get_sb,
1641 .kill_sb = kill_block_super,
1642 .fs_flags = FS_REQUIRES_DEV,
1643 };
1644
1645 static struct super_operations btrfs_super_ops = {
1646 .statfs = simple_statfs,
1647 .delete_inode = btrfs_delete_inode,
1648 .put_super = btrfs_put_super,
1649 .read_inode = btrfs_read_locked_inode,
1650 .write_super = btrfs_write_super,
1651 .sync_fs = btrfs_sync_fs,
1652 .write_inode = btrfs_write_inode,
1653 .alloc_inode = btrfs_alloc_inode,
1654 .destroy_inode = btrfs_destroy_inode,
1655 };
1656
1657 static struct inode_operations btrfs_dir_inode_operations = {
1658 .lookup = btrfs_lookup,
1659 .create = btrfs_create,
1660 .unlink = btrfs_unlink,
1661 .mkdir = btrfs_mkdir,
1662 .rmdir = btrfs_rmdir,
1663 };
1664
1665 static struct file_operations btrfs_dir_file_operations = {
1666 .llseek = generic_file_llseek,
1667 .read = generic_read_dir,
1668 .readdir = btrfs_readdir,
1669 };
1670
1671 static struct address_space_operations btrfs_aops = {
1672 .readpage = btrfs_readpage,
1673 .readpages = btrfs_readpages,
1674 .writepage = btrfs_writepage,
1675 .sync_page = block_sync_page,
1676 .prepare_write = btrfs_prepare_write,
1677 .commit_write = btrfs_commit_write,
1678 };
1679
1680 static struct inode_operations btrfs_file_inode_operations = {
1681 .truncate = btrfs_truncate,
1682 };
1683
1684 static struct file_operations btrfs_file_operations = {
1685 .llseek = generic_file_llseek,
1686 .read = do_sync_read,
1687 .aio_read = btrfs_file_aio_read,
1688 .write = btrfs_file_write,
1689 .mmap = generic_file_mmap,
1690 .open = generic_file_open,
1691 };
1692
1693 static int __init init_btrfs_fs(void)
1694 {
1695 int err;
1696 printk("btrfs loaded!\n");
1697 err = init_inodecache();
1698 if (err)
1699 return err;
1700 return register_filesystem(&btrfs_fs_type);
1701 }
1702
1703 static void __exit exit_btrfs_fs(void)
1704 {
1705 destroy_inodecache();
1706 unregister_filesystem(&btrfs_fs_type);
1707 printk("btrfs unloaded\n");
1708 }
1709
1710 module_init(init_btrfs_fs)
1711 module_exit(exit_btrfs_fs)
1712
1713 MODULE_LICENSE("GPL");
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