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Btrfs: many file_write fixes, inline data
[deliverable/linux.git] / fs / btrfs / super.c
CommitLineData
2e635a27 1#include <linux/module.h>
e20d96d6 2#include <linux/buffer_head.h>
2e635a27
CM		 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>
dee26a9f 11#include <linux/mpage.h>
75dfe396
CM		 12#include <linux/swap.h>
13#include <linux/writeback.h>
2e635a27 14#include "ctree.h"
e20d96d6 15#include "disk-io.h"
d5719762 16#include "transaction.h"
2c90e5d6 17#include "btrfs_inode.h"
c5739bba 18#include "ioctl.h"
2e635a27 19
d6e4a428
CM		 20void btrfs_fsinfo_release(struct kobject *obj)
21{
22 struct btrfs_fs_info *fsinfo = container_of(obj,
23 struct btrfs_fs_info, kobj);
24 kfree(fsinfo);
25}
26
27struct kobj_type btrfs_fsinfo_ktype = {
28 .release = btrfs_fsinfo_release,
29};
30
c5739bba
CM		 31struct btrfs_iget_args {
32 u64 ino;
33 struct btrfs_root *root;
34};
35
d6e4a428
CM		 36decl_subsys(btrfs, &btrfs_fsinfo_ktype, NULL);
37
2e635a27 38#define BTRFS_SUPER_MAGIC 0x9123682E
e20d96d6
CM		 39
40static struct inode_operations btrfs_dir_inode_operations;
d6e4a428 41static struct inode_operations btrfs_dir_ro_inode_operations;
e20d96d6
CM		 42static struct super_operations btrfs_super_ops;
43static struct file_operations btrfs_dir_file_operations;
dee26a9f
CM		 44static struct inode_operations btrfs_file_inode_operations;
45static struct address_space_operations btrfs_aops;
46static struct file_operations btrfs_file_operations;
e20d96d6 47
e20d96d6 48static void btrfs_read_locked_inode(struct inode *inode)
2e635a27 49{
5caf2a00 50 struct btrfs_path *path;
e20d96d6 51 struct btrfs_inode_item *inode_item;
d6e4a428
CM		 52 struct btrfs_root *root = BTRFS_I(inode)->root;
53 struct btrfs_key location;
e20d96d6 54 int ret;
f4b9aa8d 55
5caf2a00
CM		 56 path = btrfs_alloc_path();
57 BUG_ON(!path);
58 btrfs_init_path(path);
f4b9aa8d
CM		 59 mutex_lock(&root->fs_info->fs_mutex);
60
d6e4a428
CM		 61 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
62 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
e20d96d6 63 if (ret) {
7cfcc17e 64 btrfs_free_path(path);
d6e4a428 65 goto make_bad;
e20d96d6 66 }
5caf2a00
CM		 67 inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
68 path->slots[0],
e20d96d6 69 struct btrfs_inode_item);
2e635a27 70
e20d96d6
CM		 71 inode->i_mode = btrfs_inode_mode(inode_item);
72 inode->i_nlink = btrfs_inode_nlink(inode_item);
73 inode->i_uid = btrfs_inode_uid(inode_item);
74 inode->i_gid = btrfs_inode_gid(inode_item);
75 inode->i_size = btrfs_inode_size(inode_item);
76 inode->i_atime.tv_sec = btrfs_timespec_sec(&inode_item->atime);
77 inode->i_atime.tv_nsec = btrfs_timespec_nsec(&inode_item->atime);
78 inode->i_mtime.tv_sec = btrfs_timespec_sec(&inode_item->mtime);
79 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(&inode_item->mtime);
80 inode->i_ctime.tv_sec = btrfs_timespec_sec(&inode_item->ctime);
81 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(&inode_item->ctime);
82 inode->i_blocks = btrfs_inode_nblocks(inode_item);
83 inode->i_generation = btrfs_inode_generation(inode_item);
5caf2a00 84
5caf2a00
CM		 85 btrfs_free_path(path);
86 inode_item = NULL;
87
f4b9aa8d 88 mutex_unlock(&root->fs_info->fs_mutex);
1b05da2e 89
e20d96d6
CM		 90 switch (inode->i_mode & S_IFMT) {
91#if 0
92 default:
93 init_special_inode(inode, inode->i_mode,
94 btrfs_inode_rdev(inode_item));
95 break;
96#endif
97 case S_IFREG:
dee26a9f
CM		 98 inode->i_mapping->a_ops = &btrfs_aops;
99 inode->i_fop = &btrfs_file_operations;
100 inode->i_op = &btrfs_file_inode_operations;
e20d96d6
CM		 101 break;
102 case S_IFDIR:
e20d96d6 103 inode->i_fop = &btrfs_dir_file_operations;
d6e4a428
CM		 104 if (root == root->fs_info->tree_root)
105 inode->i_op = &btrfs_dir_ro_inode_operations;
106 else
107 inode->i_op = &btrfs_dir_inode_operations;
e20d96d6
CM		 108 break;
109 case S_IFLNK:
e20d96d6
CM		 110 // inode->i_op = &page_symlink_inode_operations;
111 break;
2e635a27 112 }
e20d96d6 113 return;
d6e4a428
CM		 114
115make_bad:
116 btrfs_release_path(root, path);
117 btrfs_free_path(path);
118 mutex_unlock(&root->fs_info->fs_mutex);
119 make_bad_inode(inode);
2e635a27
CM		 120}
121
5f443fd2
CM		 122static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
123 struct btrfs_root *root,
124 struct inode *dir,
125 struct dentry *dentry)
134e9731 126{
5caf2a00 127 struct btrfs_path *path;
134e9731
CM		 128 const char *name = dentry->d_name.name;
129 int name_len = dentry->d_name.len;
130 int ret;
131 u64 objectid;
132 struct btrfs_dir_item *di;
133
5caf2a00
CM		 134 path = btrfs_alloc_path();
135 BUG_ON(!path);
136 btrfs_init_path(path);
137 ret = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
134e9731
CM		 138 name, name_len, -1);
139 if (ret < 0)
140 goto err;
141 if (ret > 0) {
142 ret = -ENOENT;
143 goto err;
144 }
5caf2a00 145 di = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
134e9731 146 struct btrfs_dir_item);
d6e4a428 147 objectid = btrfs_disk_key_objectid(&di->location);
134e9731 148
5f26f772
CM		 149 ret = btrfs_del_item(trans, root, path);
150 BUG_ON(ret);
151
152 btrfs_release_path(root, path);
134e9731
CM		 153 dentry->d_inode->i_ctime = dir->i_ctime;
154err:
5caf2a00
CM		 155 btrfs_release_path(root, path);
156 btrfs_free_path(path);
d4dbff95 157 if (ret == 0) {
134e9731 158 inode_dec_link_count(dentry->d_inode);
5f26f772 159 dir->i_size -= name_len * 2;
d4dbff95
CM		 160 mark_inode_dirty(dir);
161 }
134e9731
CM		 162 return ret;
163}
164
5f443fd2
CM		 165static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
166{
167 struct btrfs_root *root;
168 struct btrfs_trans_handle *trans;
169 int ret;
170
d6e4a428 171 root = BTRFS_I(dir)->root;
5f443fd2
CM		 172 mutex_lock(&root->fs_info->fs_mutex);
173 trans = btrfs_start_transaction(root, 1);
174 ret = btrfs_unlink_trans(trans, root, dir, dentry);
175 btrfs_end_transaction(trans, root);
176 mutex_unlock(&root->fs_info->fs_mutex);
177 return ret;
178}
179
180static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
181{
182 struct inode *inode = dentry->d_inode;
183 int err;
184 int ret;
d6e4a428 185 struct btrfs_root *root = BTRFS_I(dir)->root;
5caf2a00 186 struct btrfs_path *path;
5f443fd2
CM		 187 struct btrfs_key key;
188 struct btrfs_trans_handle *trans;
5f26f772
CM		 189 struct btrfs_key found_key;
190 int found_type;
5f443fd2 191 struct btrfs_leaf *leaf;
5f26f772 192 char *goodnames = "..";
5f443fd2 193
5caf2a00
CM		 194 path = btrfs_alloc_path();
195 BUG_ON(!path);
196 btrfs_init_path(path);
5f443fd2
CM		 197 mutex_lock(&root->fs_info->fs_mutex);
198 trans = btrfs_start_transaction(root, 1);
199 key.objectid = inode->i_ino;
200 key.offset = (u64)-1;
5f26f772
CM		 201 key.flags = (u32)-1;
202 while(1) {
203 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
204 if (ret < 0) {
205 err = ret;
206 goto out;
207 }
208 BUG_ON(ret == 0);
209 if (path->slots[0] == 0) {
210 err = -ENOENT;
211 goto out;
212 }
213 path->slots[0]--;
214 leaf = btrfs_buffer_leaf(path->nodes[0]);
215 btrfs_disk_key_to_cpu(&found_key,
216 &leaf->items[path->slots[0]].key);
217 found_type = btrfs_key_type(&found_key);
218 if (found_key.objectid != inode->i_ino) {
219 err = -ENOENT;
220 goto out;
221 }
222 if ((found_type != BTRFS_DIR_ITEM_KEY &&
223 found_type != BTRFS_DIR_INDEX_KEY) ||
224 (!btrfs_match_dir_item_name(root, path, goodnames, 2) &&
225 !btrfs_match_dir_item_name(root, path, goodnames, 1))) {
226 err = -ENOTEMPTY;
227 goto out;
228 }
229 ret = btrfs_del_item(trans, root, path);
230 BUG_ON(ret);
5f443fd2 231
5f26f772
CM		 232 if (found_type == BTRFS_DIR_ITEM_KEY && found_key.offset == 1)
233 break;
234 btrfs_release_path(root, path);
5f443fd2 235 }
5f26f772 236 ret = 0;
5caf2a00 237 btrfs_release_path(root, path);
5f443fd2
CM		 238
239 /* now the directory is empty */
240 err = btrfs_unlink_trans(trans, root, dir, dentry);
241 if (!err) {
242 inode->i_size = 0;
243 }
244out:
7cfcc17e
CM		 245 btrfs_release_path(root, path);
246 btrfs_free_path(path);
5f443fd2
CM		 247 mutex_unlock(&root->fs_info->fs_mutex);
248 ret = btrfs_end_transaction(trans, root);
249 if (ret && !err)
250 err = ret;
251 return err;
252}
253
134e9731
CM		 254static int btrfs_free_inode(struct btrfs_trans_handle *trans,
255 struct btrfs_root *root,
256 struct inode *inode)
257{
5caf2a00 258 struct btrfs_path *path;
134e9731 259 int ret;
5caf2a00 260
134e9731 261 clear_inode(inode);
5caf2a00
CM		 262
263 path = btrfs_alloc_path();
264 BUG_ON(!path);
265 btrfs_init_path(path);
d6e4a428
CM		 266 ret = btrfs_lookup_inode(trans, root, path,
267 &BTRFS_I(inode)->location, -1);
134e9731 268 BUG_ON(ret);
5caf2a00 269 ret = btrfs_del_item(trans, root, path);
134e9731 270 BUG_ON(ret);
5caf2a00 271 btrfs_free_path(path);
134e9731
CM		 272 return ret;
273}
274
f4b9aa8d
CM		 275static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
276 struct btrfs_root *root,
277 struct inode *inode)
278{
279 int ret;
5caf2a00 280 struct btrfs_path *path;
f4b9aa8d
CM		 281 struct btrfs_key key;
282 struct btrfs_disk_key *found_key;
283 struct btrfs_leaf *leaf;
f254e52c
CM		 284 struct btrfs_file_extent_item *fi = NULL;
285 u64 extent_start = 0;
286 u64 extent_num_blocks = 0;
287 int found_extent;
f4b9aa8d 288
5caf2a00
CM		 289 path = btrfs_alloc_path();
290 BUG_ON(!path);
f4b9aa8d
CM		 291 /* FIXME, add redo link to tree so we don't leak on crash */
292 key.objectid = inode->i_ino;
293 key.offset = (u64)-1;
294 key.flags = 0;
d4dbff95
CM		 295 /*
296 * use BTRFS_CSUM_ITEM_KEY because it is larger than inline keys
297 * or extent data
298 */
f254e52c 299 btrfs_set_key_type(&key, BTRFS_CSUM_ITEM_KEY);
f4b9aa8d 300 while(1) {
5caf2a00
CM		 301 btrfs_init_path(path);
302 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
f4b9aa8d 303 if (ret < 0) {
f4b9aa8d
CM		 304 goto error;
305 }
306 if (ret > 0) {
5caf2a00
CM		 307 BUG_ON(path->slots[0] == 0);
308 path->slots[0]--;
f4b9aa8d 309 }
5caf2a00
CM		 310 leaf = btrfs_buffer_leaf(path->nodes[0]);
311 found_key = &leaf->items[path->slots[0]].key;
f4b9aa8d
CM		 312 if (btrfs_disk_key_objectid(found_key) != inode->i_ino)
313 break;
f254e52c 314 if (btrfs_disk_key_type(found_key) != BTRFS_CSUM_ITEM_KEY &&
d4dbff95 315 btrfs_disk_key_type(found_key) != BTRFS_INLINE_DATA_KEY &&
f254e52c 316 btrfs_disk_key_type(found_key) != BTRFS_EXTENT_DATA_KEY)
f4b9aa8d 317 break;
f4b9aa8d
CM		 318 if (btrfs_disk_key_offset(found_key) < inode->i_size)
319 break;
236454df 320 found_extent = 0;
f254e52c 321 if (btrfs_disk_key_type(found_key) == BTRFS_EXTENT_DATA_KEY) {
5caf2a00
CM		 322 fi = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
323 path->slots[0],
f254e52c 324 struct btrfs_file_extent_item);
236454df
CM		 325 if (btrfs_file_extent_type(fi) !=
326 BTRFS_FILE_EXTENT_INLINE) {
327 extent_start =
328 btrfs_file_extent_disk_blocknr(fi);
329 extent_num_blocks =
330 btrfs_file_extent_disk_num_blocks(fi);
331 /* FIXME blocksize != 4096 */
332 inode->i_blocks -=
333 btrfs_file_extent_num_blocks(fi) << 3;
334 found_extent = 1;
335 }
f254e52c 336 }
5caf2a00 337 ret = btrfs_del_item(trans, root, path);
f4b9aa8d 338 BUG_ON(ret);
5caf2a00 339 btrfs_release_path(root, path);
f254e52c
CM		 340 if (found_extent) {
341 ret = btrfs_free_extent(trans, root, extent_start,
342 extent_num_blocks, 0);
343 BUG_ON(ret);
344 }
f4b9aa8d 345 }
f4b9aa8d
CM		 346 ret = 0;
347error:
5caf2a00
CM		 348 btrfs_release_path(root, path);
349 btrfs_free_path(path);
f4b9aa8d
CM		 350 return ret;
351}
352
134e9731
CM		 353static void btrfs_delete_inode(struct inode *inode)
354{
355 struct btrfs_trans_handle *trans;
d6e4a428 356 struct btrfs_root *root = BTRFS_I(inode)->root;
f4b9aa8d
CM		 357 int ret;
358
134e9731
CM		 359 truncate_inode_pages(&inode->i_data, 0);
360 if (is_bad_inode(inode)) {
361 goto no_delete;
362 }
363 inode->i_size = 0;
134e9731
CM		 364 mutex_lock(&root->fs_info->fs_mutex);
365 trans = btrfs_start_transaction(root, 1);
f4b9aa8d
CM		 366 if (S_ISREG(inode->i_mode)) {
367 ret = btrfs_truncate_in_trans(trans, root, inode);
368 BUG_ON(ret);
369 }
134e9731
CM		 370 btrfs_free_inode(trans, root, inode);
371 btrfs_end_transaction(trans, root);
372 mutex_unlock(&root->fs_info->fs_mutex);
373 return;
374no_delete:
375 clear_inode(inode);
376}
377
e20d96d6 378static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
d6e4a428 379 struct btrfs_key *location)
e20d96d6
CM		 380{
381 const char *name = dentry->d_name.name;
382 int namelen = dentry->d_name.len;
383 struct btrfs_dir_item *di;
5caf2a00 384 struct btrfs_path *path;
d6e4a428 385 struct btrfs_root *root = BTRFS_I(dir)->root;
e20d96d6
CM		 386 int ret;
387
5caf2a00
CM		 388 path = btrfs_alloc_path();
389 BUG_ON(!path);
390 btrfs_init_path(path);
391 ret = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
e20d96d6 392 namelen, 0);
5caf2a00 393 if (ret || !btrfs_match_dir_item_name(root, path, name, namelen)) {
d6e4a428 394 location->objectid = 0;
2c90e5d6 395 ret = 0;
e20d96d6
CM		 396 goto out;
397 }
5caf2a00 398 di = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
e20d96d6 399 struct btrfs_dir_item);
d6e4a428 400 btrfs_disk_key_to_cpu(location, &di->location);
e20d96d6 401out:
5caf2a00
CM		 402 btrfs_release_path(root, path);
403 btrfs_free_path(path);
e20d96d6
CM		 404 return ret;
405}
406
d6e4a428
CM		 407int fixup_tree_root_location(struct btrfs_root *root,
408 struct btrfs_key *location,
409 struct btrfs_root **sub_root)
410{
411 struct btrfs_path *path;
412 struct btrfs_root_item *ri;
d6e4a428
CM		 413
414 if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
415 return 0;
416 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
417 return 0;
418
419 path = btrfs_alloc_path();
420 BUG_ON(!path);
421 mutex_lock(&root->fs_info->fs_mutex);
422
0f7d52f4
CM		 423 *sub_root = btrfs_read_fs_root(root->fs_info, location);
424 if (IS_ERR(*sub_root))
425 return PTR_ERR(*sub_root);
426
427 ri = &(*sub_root)->root_item;
d6e4a428
CM		 428 location->objectid = btrfs_root_dirid(ri);
429 location->flags = 0;
430 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
431 location->offset = 0;
0f7d52f4 432
d6e4a428
CM		 433 btrfs_free_path(path);
434 mutex_unlock(&root->fs_info->fs_mutex);
0f7d52f4 435 return 0;
d6e4a428
CM		 436}
437
c5739bba
CM		 438int btrfs_init_locked_inode(struct inode *inode, void *p)
439{
440 struct btrfs_iget_args *args = p;
441 inode->i_ino = args->ino;
442 BTRFS_I(inode)->root = args->root;
443 return 0;
444}
445
446int btrfs_find_actor(struct inode *inode, void *opaque)
447{
448 struct btrfs_iget_args *args = opaque;
449 return (args->ino == inode->i_ino &&
450 args->root == BTRFS_I(inode)->root);
451}
452
453struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
454 struct btrfs_root *root)
455{
456 struct inode *inode;
457 struct btrfs_iget_args args;
458 args.ino = objectid;
459 args.root = root;
460
461 inode = iget5_locked(s, objectid, btrfs_find_actor,
462 btrfs_init_locked_inode,
463 (void *)&args);
464 return inode;
465}
d6e4a428 466
e20d96d6
CM		 467static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
468 struct nameidata *nd)
469{
470 struct inode * inode;
d6e4a428
CM		 471 struct btrfs_inode *bi = BTRFS_I(dir);
472 struct btrfs_root *root = bi->root;
473 struct btrfs_root *sub_root = root;
474 struct btrfs_key location;
e20d96d6
CM		 475 int ret;
476
477 if (dentry->d_name.len > BTRFS_NAME_LEN)
478 return ERR_PTR(-ENAMETOOLONG);
22b0ebda 479 mutex_lock(&root->fs_info->fs_mutex);
d6e4a428 480 ret = btrfs_inode_by_name(dir, dentry, &location);
22b0ebda 481 mutex_unlock(&root->fs_info->fs_mutex);
e20d96d6
CM		 482 if (ret < 0)
483 return ERR_PTR(ret);
484 inode = NULL;
d6e4a428
CM		 485 if (location.objectid) {
486 ret = fixup_tree_root_location(root, &location, &sub_root);
487 if (ret < 0)
488 return ERR_PTR(ret);
489 if (ret > 0)
490 return ERR_PTR(-ENOENT);
c5739bba
CM		 491 inode = btrfs_iget_locked(dir->i_sb, location.objectid,
492 sub_root);
e20d96d6
CM		 493 if (!inode)
494 return ERR_PTR(-EACCES);
d6e4a428 495 if (inode->i_state & I_NEW) {
0f7d52f4 496 if (sub_root != root) {
c5739bba 497printk("adding new root for inode %lu root %p (found %p)\n", inode->i_ino, sub_root, BTRFS_I(inode)->root);
0f7d52f4
CM		 498 igrab(inode);
499 sub_root->inode = inode;
500 }
d6e4a428
CM		 501 BTRFS_I(inode)->root = sub_root;
502 memcpy(&BTRFS_I(inode)->location, &location,
503 sizeof(location));
504 btrfs_read_locked_inode(inode);
505 unlock_new_inode(inode);
506 }
e20d96d6
CM		 507 }
508 return d_splice_alias(inode, dentry);
509}
510
511static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
512{
513 struct inode *inode = filp->f_path.dentry->d_inode;
d6e4a428 514 struct btrfs_root *root = BTRFS_I(inode)->root;
e20d96d6
CM		 515 struct btrfs_item *item;
516 struct btrfs_dir_item *di;
517 struct btrfs_key key;
5caf2a00 518 struct btrfs_path *path;
e20d96d6
CM		 519 int ret;
520 u32 nritems;
521 struct btrfs_leaf *leaf;
522 int slot;
523 int advance;
524 unsigned char d_type = DT_UNKNOWN;
7f5c1516 525 int over = 0;
70b2befd 526 int key_type = BTRFS_DIR_ITEM_KEY;
d6e4a428
CM		 527
528 /* FIXME, use a real flag for deciding about the key type */
529 if (root->fs_info->tree_root == root)
530 key_type = BTRFS_DIR_ITEM_KEY;
22b0ebda 531 mutex_lock(&root->fs_info->fs_mutex);
e20d96d6 532 key.objectid = inode->i_ino;
e20d96d6 533 key.flags = 0;
d6e4a428 534 btrfs_set_key_type(&key, key_type);
e20d96d6 535 key.offset = filp->f_pos;
5caf2a00
CM		 536 path = btrfs_alloc_path();
537 btrfs_init_path(path);
538 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1b05da2e 539 if (ret < 0)
e20d96d6 540 goto err;
7f5c1516 541 advance = 0;
e20d96d6 542 while(1) {
5caf2a00 543 leaf = btrfs_buffer_leaf(path->nodes[0]);
e20d96d6 544 nritems = btrfs_header_nritems(&leaf->header);
5caf2a00 545 slot = path->slots[0];
dee26a9f
CM		 546 if (advance || slot >= nritems) {
547 if (slot >= nritems -1) {
5caf2a00 548 ret = btrfs_next_leaf(root, path);
e20d96d6
CM		 549 if (ret)
550 break;
5caf2a00 551 leaf = btrfs_buffer_leaf(path->nodes[0]);
e20d96d6 552 nritems = btrfs_header_nritems(&leaf->header);
5caf2a00 553 slot = path->slots[0];
e20d96d6
CM		 554 } else {
555 slot++;
5caf2a00 556 path->slots[0]++;
e20d96d6
CM		 557 }
558 }
559 advance = 1;
560 item = leaf->items + slot;
e20d96d6
CM		 561 if (btrfs_disk_key_objectid(&item->key) != key.objectid)
562 break;
d6e4a428 563 if (btrfs_disk_key_type(&item->key) != key_type)
a429e513 564 break;
7f5c1516
CM		 565 if (btrfs_disk_key_offset(&item->key) < filp->f_pos)
566 continue;
7fcde0e3 567 filp->f_pos = btrfs_disk_key_offset(&item->key);
dee26a9f 568 advance = 1;
e20d96d6 569 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
e20d96d6
CM		 570 over = filldir(dirent, (const char *)(di + 1),
571 btrfs_dir_name_len(di),
572 btrfs_disk_key_offset(&item->key),
d6e4a428 573 btrfs_disk_key_objectid(&di->location), d_type);
7fcde0e3
CM		 574 if (over)
575 goto nopos;
e20d96d6 576 }
7fcde0e3
CM		 577 filp->f_pos++;
578nopos:
e20d96d6
CM		 579 ret = 0;
580err:
5caf2a00
CM		 581 btrfs_release_path(root, path);
582 btrfs_free_path(path);
22b0ebda 583 mutex_unlock(&root->fs_info->fs_mutex);
e20d96d6
CM		 584 return ret;
585}
586
587static void btrfs_put_super (struct super_block * sb)
588{
589 struct btrfs_root *root = btrfs_sb(sb);
590 int ret;
591
592 ret = close_ctree(root);
593 if (ret) {
594 printk("close ctree returns %d\n", ret);
595 }
596 sb->s_fs_info = NULL;
597}
2e635a27
CM		 598
599static int btrfs_fill_super(struct super_block * sb, void * data, int silent)
600{
601 struct inode * inode;
e20d96d6
CM		 602 struct dentry * root_dentry;
603 struct btrfs_super_block *disk_super;
0f7d52f4 604 struct btrfs_root *tree_root;
d6e4a428 605 struct btrfs_inode *bi;
2e635a27
CM		 606
607 sb->s_maxbytes = MAX_LFS_FILESIZE;
2e635a27 608 sb->s_magic = BTRFS_SUPER_MAGIC;
e20d96d6 609 sb->s_op = &btrfs_super_ops;
2e635a27 610 sb->s_time_gran = 1;
e20d96d6 611
0f7d52f4 612 tree_root = open_ctree(sb);
d98237b3 613
0f7d52f4 614 if (!tree_root) {
e20d96d6
CM		 615 printk("btrfs: open_ctree failed\n");
616 return -EIO;
617 }
0f7d52f4
CM		 618 sb->s_fs_info = tree_root;
619 disk_super = tree_root->fs_info->disk_super;
e20d96d6
CM		 620 printk("read in super total blocks %Lu root %Lu\n",
621 btrfs_super_total_blocks(disk_super),
622 btrfs_super_root_dir(disk_super));
623
c5739bba
CM		 624 inode = btrfs_iget_locked(sb, btrfs_super_root_dir(disk_super),
625 tree_root);
d6e4a428
CM		 626 bi = BTRFS_I(inode);
627 bi->location.objectid = inode->i_ino;
628 bi->location.offset = 0;
629 bi->location.flags = 0;
0f7d52f4 630 bi->root = tree_root;
d6e4a428
CM		 631 btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY);
632
2e635a27
CM		 633 if (!inode)
634 return -ENOMEM;
e20d96d6
CM		 635 if (inode->i_state & I_NEW) {
636 btrfs_read_locked_inode(inode);
637 unlock_new_inode(inode);
638 }
2e635a27 639
e20d96d6
CM		 640 root_dentry = d_alloc_root(inode);
641 if (!root_dentry) {
2e635a27
CM		 642 iput(inode);
643 return -ENOMEM;
644 }
e20d96d6
CM		 645 sb->s_root = root_dentry;
646
2e635a27
CM		 647 return 0;
648}
649
d5719762
CM		 650static void fill_inode_item(struct btrfs_inode_item *item,
651 struct inode *inode)
652{
653 btrfs_set_inode_uid(item, inode->i_uid);
654 btrfs_set_inode_gid(item, inode->i_gid);
655 btrfs_set_inode_size(item, inode->i_size);
656 btrfs_set_inode_mode(item, inode->i_mode);
657 btrfs_set_inode_nlink(item, inode->i_nlink);
658 btrfs_set_timespec_sec(&item->atime, inode->i_atime.tv_sec);
659 btrfs_set_timespec_nsec(&item->atime, inode->i_atime.tv_nsec);
660 btrfs_set_timespec_sec(&item->mtime, inode->i_mtime.tv_sec);
661 btrfs_set_timespec_nsec(&item->mtime, inode->i_mtime.tv_nsec);
662 btrfs_set_timespec_sec(&item->ctime, inode->i_ctime.tv_sec);
663 btrfs_set_timespec_nsec(&item->ctime, inode->i_ctime.tv_nsec);
664 btrfs_set_inode_nblocks(item, inode->i_blocks);
665 btrfs_set_inode_generation(item, inode->i_generation);
666}
667
4730a4bc
CM		 668static int btrfs_update_inode(struct btrfs_trans_handle *trans,
669 struct btrfs_root *root,
670 struct inode *inode)
671{
672 struct btrfs_inode_item *inode_item;
5caf2a00 673 struct btrfs_path *path;
4730a4bc
CM		 674 int ret;
675
5caf2a00
CM		 676 path = btrfs_alloc_path();
677 BUG_ON(!path);
678 btrfs_init_path(path);
d6e4a428
CM		 679 ret = btrfs_lookup_inode(trans, root, path,
680 &BTRFS_I(inode)->location, 1);
4730a4bc
CM		 681 if (ret) {
682 if (ret > 0)
683 ret = -ENOENT;
684 goto failed;
685 }
686
5caf2a00
CM		 687 inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
688 path->slots[0],
4730a4bc
CM		 689 struct btrfs_inode_item);
690
691 fill_inode_item(inode_item, inode);
5caf2a00 692 btrfs_mark_buffer_dirty(path->nodes[0]);
1b05da2e 693 ret = 0;
4730a4bc 694failed:
5caf2a00
CM		 695 btrfs_release_path(root, path);
696 btrfs_free_path(path);
1b05da2e 697 return ret;
4730a4bc
CM		 698}
699
700static int btrfs_write_inode(struct inode *inode, int wait)
701{
d6e4a428 702 struct btrfs_root *root = BTRFS_I(inode)->root;
4730a4bc
CM		 703 struct btrfs_trans_handle *trans;
704 int ret;
705
706 mutex_lock(&root->fs_info->fs_mutex);
707 trans = btrfs_start_transaction(root, 1);
708 ret = btrfs_update_inode(trans, root, inode);
709 if (wait)
710 btrfs_commit_transaction(trans, root);
711 else
712 btrfs_end_transaction(trans, root);
713 mutex_unlock(&root->fs_info->fs_mutex);
714 return ret;
715}
716
d5719762 717static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
2619ba1f
CM		 718 struct btrfs_root *root,
719 u64 objectid, int mode)
d5719762
CM		 720{
721 struct inode *inode;
722 struct btrfs_inode_item inode_item;
1b05da2e 723 struct btrfs_key *location;
d5719762 724 int ret;
d5719762 725
2619ba1f 726 inode = new_inode(root->fs_info->sb);
d5719762
CM		 727 if (!inode)
728 return ERR_PTR(-ENOMEM);
729
2619ba1f 730 BTRFS_I(inode)->root = root;
d5719762
CM		 731
732 inode->i_uid = current->fsuid;
733 inode->i_gid = current->fsgid;
734 inode->i_mode = mode;
735 inode->i_ino = objectid;
736 inode->i_blocks = 0;
c5739bba 737 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
d5719762 738 fill_inode_item(&inode_item, inode);
1b05da2e
CM		 739 location = &BTRFS_I(inode)->location;
740 location->objectid = objectid;
741 location->flags = 0;
742 location->offset = 0;
743 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
d5719762
CM		 744
745 ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
746 BUG_ON(ret);
747
748 insert_inode_hash(inode);
d5719762
CM		 749 return inode;
750}
751
752static int btrfs_add_link(struct btrfs_trans_handle *trans,
753 struct dentry *dentry, struct inode *inode)
754{
755 int ret;
d6e4a428
CM		 756 struct btrfs_key key;
757 struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
758 key.objectid = inode->i_ino;
759 key.flags = 0;
760 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
761 key.offset = 0;
762
763 ret = btrfs_insert_dir_item(trans, root,
d5719762
CM		 764 dentry->d_name.name, dentry->d_name.len,
765 dentry->d_parent->d_inode->i_ino,
d6e4a428 766 &key, 0);
4730a4bc 767 if (ret == 0) {
5f26f772 768 dentry->d_parent->d_inode->i_size += dentry->d_name.len * 2;
d6e4a428 769 ret = btrfs_update_inode(trans, root,
4730a4bc
CM		 770 dentry->d_parent->d_inode);
771 }
d5719762
CM		 772 return ret;
773}
774
775static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
776 struct dentry *dentry, struct inode *inode)
777{
778 int err = btrfs_add_link(trans, dentry, inode);
779 if (!err) {
780 d_instantiate(dentry, inode);
781 return 0;
782 }
2c90e5d6
CM		 783 if (err > 0)
784 err = -EEXIST;
d5719762
CM		 785 return err;
786}
787
788static int btrfs_create(struct inode *dir, struct dentry *dentry,
789 int mode, struct nameidata *nd)
790{
791 struct btrfs_trans_handle *trans;
d6e4a428 792 struct btrfs_root *root = BTRFS_I(dir)->root;
d5719762
CM		 793 struct inode *inode;
794 int err;
134e9731 795 int drop_inode = 0;
2619ba1f 796 u64 objectid;
d5719762 797
d561c025 798 mutex_lock(&root->fs_info->fs_mutex);
d5719762 799 trans = btrfs_start_transaction(root, 1);
2619ba1f
CM		 800
801 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
802 if (err) {
803 err = -ENOSPC;
804 goto out_unlock;
805 }
806
807 inode = btrfs_new_inode(trans, root, objectid, mode);
d5719762
CM		 808 err = PTR_ERR(inode);
809 if (IS_ERR(inode))
d561c025 810 goto out_unlock;
d5719762
CM		 811 // FIXME mark the inode dirty
812 err = btrfs_add_nondir(trans, dentry, inode);
134e9731
CM		 813 if (err)
814 drop_inode = 1;
dee26a9f
CM		 815 else {
816 inode->i_mapping->a_ops = &btrfs_aops;
817 inode->i_fop = &btrfs_file_operations;
818 inode->i_op = &btrfs_file_inode_operations;
819 }
d5719762 820 dir->i_sb->s_dirt = 1;
d561c025 821out_unlock:
22b0ebda 822 btrfs_end_transaction(trans, root);
d561c025 823 mutex_unlock(&root->fs_info->fs_mutex);
2c90e5d6 824
134e9731
CM		 825 if (drop_inode) {
826 inode_dec_link_count(inode);
827 iput(inode);
828 }
d5719762
CM		 829 return err;
830}
831
f7922033 832static int btrfs_make_empty_dir(struct btrfs_trans_handle *trans,
2619ba1f
CM		 833 struct btrfs_root *root,
834 u64 objectid, u64 dirid)
f7922033 835{
f7922033
CM		 836 int ret;
837 char buf[2];
d6e4a428
CM		 838 struct btrfs_key key;
839
f7922033
CM		 840 buf[0] = '.';
841 buf[1] = '.';
842
2619ba1f 843 key.objectid = objectid;
d6e4a428
CM		 844 key.offset = 0;
845 key.flags = 0;
846 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
847
2619ba1f 848 ret = btrfs_insert_dir_item(trans, root, buf, 1, objectid,
d6e4a428 849 &key, 1);
f7922033
CM		 850 if (ret)
851 goto error;
2619ba1f
CM		 852 key.objectid = dirid;
853 ret = btrfs_insert_dir_item(trans, root, buf, 2, objectid,
d6e4a428 854 &key, 1);
4730a4bc
CM		 855 if (ret)
856 goto error;
f7922033
CM		 857error:
858 return ret;
859}
860
861static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
862{
863 struct inode *inode;
864 struct btrfs_trans_handle *trans;
d6e4a428 865 struct btrfs_root *root = BTRFS_I(dir)->root;
f7922033
CM		 866 int err = 0;
867 int drop_on_err = 0;
2619ba1f 868 u64 objectid;
f7922033
CM		 869
870 mutex_lock(&root->fs_info->fs_mutex);
871 trans = btrfs_start_transaction(root, 1);
872 if (IS_ERR(trans)) {
873 err = PTR_ERR(trans);
874 goto out_unlock;
875 }
2619ba1f
CM		 876
877 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
878 if (err) {
879 err = -ENOSPC;
880 goto out_unlock;
881 }
882
883 inode = btrfs_new_inode(trans, root, objectid, S_IFDIR | mode);
f7922033
CM		 884 if (IS_ERR(inode)) {
885 err = PTR_ERR(inode);
886 goto out_fail;
887 }
888 drop_on_err = 1;
889 inode->i_op = &btrfs_dir_inode_operations;
890 inode->i_fop = &btrfs_dir_file_operations;
891
2619ba1f
CM		 892 err = btrfs_make_empty_dir(trans, root, inode->i_ino, dir->i_ino);
893 if (err)
894 goto out_fail;
895
896 inode->i_size = 6;
897 err = btrfs_update_inode(trans, root, inode);
f7922033
CM		 898 if (err)
899 goto out_fail;
900 err = btrfs_add_link(trans, dentry, inode);
901 if (err)
902 goto out_fail;
903 d_instantiate(dentry, inode);
f7922033
CM		 904 drop_on_err = 0;
905
906out_fail:
907 btrfs_end_transaction(trans, root);
908out_unlock:
909 mutex_unlock(&root->fs_info->fs_mutex);
910 if (drop_on_err)
911 iput(inode);
912 return err;
913}
914
d5719762
CM		 915static int btrfs_sync_fs(struct super_block *sb, int wait)
916{
917 struct btrfs_trans_handle *trans;
918 struct btrfs_root *root;
919 int ret;
d98237b3 920 root = btrfs_sb(sb);
df2ce34c 921
d5719762 922 sb->s_dirt = 0;
d561c025 923 if (!wait) {
7cfcc17e 924 filemap_flush(root->fs_info->btree_inode->i_mapping);
d561c025
CM		 925 return 0;
926 }
7cfcc17e 927 filemap_write_and_wait(root->fs_info->btree_inode->i_mapping);
d561c025 928 mutex_lock(&root->fs_info->fs_mutex);
d5719762
CM		 929 trans = btrfs_start_transaction(root, 1);
930 ret = btrfs_commit_transaction(trans, root);
931 sb->s_dirt = 0;
932 BUG_ON(ret);
933printk("btrfs sync_fs\n");
d561c025 934 mutex_unlock(&root->fs_info->fs_mutex);
d5719762
CM		 935 return 0;
936}
937
e8f05c45 938#if 0
df24a2b9
CM		 939static int btrfs_get_block_inline(struct inode *inode, sector_t iblock,
940 struct buffer_head *result, int create)
941{
942 struct btrfs_root *root = btrfs_sb(inode->i_sb);
943 struct btrfs_path *path;
944 struct btrfs_key key;
945 struct btrfs_leaf *leaf;
946 int num_bytes = result->b_size;
947 int item_size;
948 int ret;
949 u64 pos;
950 char *ptr;
951 int copy_size;
952 int err = 0;
953 char *safe_ptr;
954 char *data_ptr;
955
956 path = btrfs_alloc_path();
957 BUG_ON(!path);
958
959 WARN_ON(create);
960 if (create) {
961 return 0;
962 }
963 pos = iblock << inode->i_blkbits;
964 key.objectid = inode->i_ino;
965 key.flags = 0;
966 btrfs_set_key_type(&key, BTRFS_INLINE_DATA_KEY);
967 ptr = kmap(result->b_page);
968 safe_ptr = ptr;
969 ptr += (pos & (PAGE_CACHE_SIZE -1));
970again:
971 key.offset = pos;
972 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
973 if (ret) {
974 if (ret < 0)
975 err = ret;
976 else
977 err = 0;
978 goto out;
979 }
980 leaf = btrfs_buffer_leaf(path->nodes[0]);
981 item_size = btrfs_item_size(leaf->items + path->slots[0]);
982 copy_size = min(num_bytes, item_size);
983 data_ptr = btrfs_item_ptr(leaf, path->slots[0], char);
984 WARN_ON(safe_ptr + PAGE_CACHE_SIZE < ptr + copy_size);
985 memcpy(ptr, data_ptr, copy_size);
986 pos += copy_size;
987 num_bytes -= copy_size;
988 WARN_ON(num_bytes < 0);
989 ptr += copy_size;
990 btrfs_release_path(root, path);
991 if (num_bytes != 0) {
992 if (pos >= i_size_read(inode))
993 memset(ptr, 0, num_bytes);
994 else
995 goto again;
996 }
997 set_buffer_uptodate(result);
998 map_bh(result, inode->i_sb, 0);
999 err = 0;
1000out:
1001 btrfs_free_path(path);
1002 kunmap(result->b_page);
1003 return err;
1004}
e8f05c45 1005#endif
df24a2b9 1006
75dfe396 1007static int btrfs_get_block_lock(struct inode *inode, sector_t iblock,
dee26a9f
CM		 1008 struct buffer_head *result, int create)
1009{
1010 int ret;
1011 int err = 0;
1012 u64 blocknr;
1013 u64 extent_start = 0;
1014 u64 extent_end = 0;
1015 u64 objectid = inode->i_ino;
236454df 1016 u32 found_type;
5caf2a00 1017 struct btrfs_path *path;
d6e4a428 1018 struct btrfs_root *root = BTRFS_I(inode)->root;
dee26a9f
CM		 1019 struct btrfs_file_extent_item *item;
1020 struct btrfs_leaf *leaf;
1021 struct btrfs_disk_key *found_key;
1022
5caf2a00
CM		 1023 path = btrfs_alloc_path();
1024 BUG_ON(!path);
1025 btrfs_init_path(path);
6567e837 1026 if (create) {
6567e837
CM		 1027 WARN_ON(1);
1028 }
dee26a9f 1029
236454df 1030 ret = btrfs_lookup_file_extent(NULL, root, path,
9773a788 1031 inode->i_ino,
236454df 1032 iblock << inode->i_blkbits, 0);
dee26a9f 1033 if (ret < 0) {
dee26a9f
CM		 1034 err = ret;
1035 goto out;
1036 }
1037
1038 if (ret != 0) {
5caf2a00
CM		 1039 if (path->slots[0] == 0) {
1040 btrfs_release_path(root, path);
236454df 1041 goto out;
dee26a9f 1042 }
5caf2a00 1043 path->slots[0]--;
dee26a9f
CM		 1044 }
1045
5caf2a00 1046 item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
dee26a9f 1047 struct btrfs_file_extent_item);
5caf2a00 1048 leaf = btrfs_buffer_leaf(path->nodes[0]);
dee26a9f
CM		 1049 blocknr = btrfs_file_extent_disk_blocknr(item);
1050 blocknr += btrfs_file_extent_offset(item);
1051
dee26a9f 1052 /* are we inside the extent that was found? */
5caf2a00 1053 found_key = &leaf->items[path->slots[0]].key;
236454df 1054 found_type = btrfs_disk_key_type(found_key);
dee26a9f 1055 if (btrfs_disk_key_objectid(found_key) != objectid ||
236454df 1056 found_type != BTRFS_EXTENT_DATA_KEY) {
dee26a9f
CM		 1057 extent_end = 0;
1058 extent_start = 0;
5caf2a00 1059 btrfs_release_path(root, path);
dee26a9f
CM		 1060 goto out;
1061 }
236454df
CM		 1062 found_type = btrfs_file_extent_type(item);
1063 extent_start = btrfs_disk_key_offset(&leaf->items[path->slots[0]].key);
1064 if (found_type == BTRFS_FILE_EXTENT_REG) {
1065 extent_start = extent_start >> inode->i_blkbits;
1066 extent_end = extent_start + btrfs_file_extent_num_blocks(item);
1067 if (iblock >= extent_start && iblock < extent_end) {
1068 err = 0;
1069 btrfs_map_bh_to_logical(root, result, blocknr +
1070 iblock - extent_start);
1071 goto out;
1072 }
1073 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
1074 char *ptr;
1075 char *map;
1076 u32 size;
1077 size = btrfs_file_extent_inline_len(leaf->items +
1078 path->slots[0]);
1079 extent_end = (extent_start + size) >> inode->i_blkbits;
1080 extent_start >>= inode->i_blkbits;
1081 if (iblock < extent_start || iblock > extent_end) {
1082 goto out;
1083 }
1084 ptr = btrfs_file_extent_inline_start(item);
1085 map = kmap(result->b_page);
1086 memcpy(map, ptr, size);
1087 memset(map + size, 0, PAGE_CACHE_SIZE - size);
1088 flush_dcache_page(result->b_page);
1089 kunmap(result->b_page);
1090 set_buffer_uptodate(result);
1091 SetPageChecked(result->b_page);
1092 btrfs_map_bh_to_logical(root, result, 0);
dee26a9f 1093 }
dee26a9f 1094out:
5caf2a00
CM		 1095 btrfs_release_path(root, path);
1096 btrfs_free_path(path);
75dfe396
CM		 1097 return err;
1098}
1099
1100static int btrfs_get_block(struct inode *inode, sector_t iblock,
1101 struct buffer_head *result, int create)
1102{
1103 int err;
d6e4a428 1104 struct btrfs_root *root = BTRFS_I(inode)->root;
75dfe396 1105 mutex_lock(&root->fs_info->fs_mutex);
e8f05c45 1106 err = btrfs_get_block_lock(inode, iblock, result, create);
dee26a9f
CM		 1107 mutex_unlock(&root->fs_info->fs_mutex);
1108 return err;
1109}
1110
1111static int btrfs_prepare_write(struct file *file, struct page *page,
1112 unsigned from, unsigned to)
1113{
6407bf6d 1114 return nobh_prepare_write(page, from, to, btrfs_get_block);
dee26a9f
CM		 1115}
1116
d561c025
CM		 1117static void btrfs_write_super(struct super_block *sb)
1118{
1119 btrfs_sync_fs(sb, 1);
1120}
1121
dee26a9f
CM		 1122static int btrfs_readpage(struct file *file, struct page *page)
1123{
1124 return mpage_readpage(page, btrfs_get_block);
1125}
1126
236454df
CM		 1127/*
1128 * While block_write_full_page is writing back the dirty buffers under
1129 * the page lock, whoever dirtied the buffers may decide to clean them
1130 * again at any time. We handle that by only looking at the buffer
1131 * state inside lock_buffer().
1132 *
1133 * If block_write_full_page() is called for regular writeback
1134 * (wbc->sync_mode == WB_SYNC_NONE) then it will redirty a page which has a
1135 * locked buffer. This only can happen if someone has written the buffer
1136 * directly, with submit_bh(). At the address_space level PageWriteback
1137 * prevents this contention from occurring.
1138 */
1139static int __btrfs_write_full_page(struct inode *inode, struct page *page,
1140 struct writeback_control *wbc)
1141{
1142 int err;
1143 sector_t block;
1144 sector_t last_block;
1145 struct buffer_head *bh, *head;
1146 const unsigned blocksize = 1 << inode->i_blkbits;
1147 int nr_underway = 0;
1148
1149 BUG_ON(!PageLocked(page));
1150
1151 last_block = (i_size_read(inode) - 1) >> inode->i_blkbits;
1152
1153 if (!page_has_buffers(page)) {
1154 create_empty_buffers(page, blocksize,
1155 (1 << BH_Dirty)|(1 << BH_Uptodate));
1156 }
1157
1158 /*
1159 * Be very careful. We have no exclusion from __set_page_dirty_buffers
1160 * here, and the (potentially unmapped) buffers may become dirty at
1161 * any time. If a buffer becomes dirty here after we've inspected it
1162 * then we just miss that fact, and the page stays dirty.
1163 *
1164 * Buffers outside i_size may be dirtied by __set_page_dirty_buffers;
1165 * handle that here by just cleaning them.
1166 */
1167
1168 block = (sector_t)page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
1169 head = page_buffers(page);
1170 bh = head;
1171
1172 /*
1173 * Get all the dirty buffers mapped to disk addresses and
1174 * handle any aliases from the underlying blockdev's mapping.
1175 */
1176 do {
1177 if (block > last_block) {
1178 /*
1179 * mapped buffers outside i_size will occur, because
1180 * this page can be outside i_size when there is a
1181 * truncate in progress.
1182 */
1183 /*
1184 * The buffer was zeroed by block_write_full_page()
1185 */
1186 clear_buffer_dirty(bh);
1187 set_buffer_uptodate(bh);
1188 } else if (!buffer_mapped(bh) && buffer_dirty(bh)) {
1189 WARN_ON(bh->b_size != blocksize);
1190 err = btrfs_get_block(inode, block, bh, 0);
1191 if (err)
1192 goto recover;
1193 if (buffer_new(bh)) {
1194 /* blockdev mappings never come here */
1195 clear_buffer_new(bh);
1196 unmap_underlying_metadata(bh->b_bdev,
1197 bh->b_blocknr);
1198 }
1199 }
1200 bh = bh->b_this_page;
1201 block++;
1202 } while (bh != head);
1203
1204 do {
1205 if (!buffer_mapped(bh))
1206 continue;
1207 /*
1208 * If it's a fully non-blocking write attempt and we cannot
1209 * lock the buffer then redirty the page. Note that this can
1210 * potentially cause a busy-wait loop from pdflush and kswapd
1211 * activity, but those code paths have their own higher-level
1212 * throttling.
1213 */
1214 if (wbc->sync_mode != WB_SYNC_NONE || !wbc->nonblocking) {
1215 lock_buffer(bh);
1216 } else if (test_set_buffer_locked(bh)) {
1217 redirty_page_for_writepage(wbc, page);
1218 continue;
1219 }
1220 if (test_clear_buffer_dirty(bh) && bh->b_blocknr != 0) {
1221 mark_buffer_async_write(bh);
1222 } else {
1223 unlock_buffer(bh);
1224 }
1225 } while ((bh = bh->b_this_page) != head);
1226
1227 /*
1228 * The page and its buffers are protected by PageWriteback(), so we can
1229 * drop the bh refcounts early.
1230 */
1231 BUG_ON(PageWriteback(page));
1232 set_page_writeback(page);
1233
1234 do {
1235 struct buffer_head *next = bh->b_this_page;
1236 if (buffer_async_write(bh)) {
1237 submit_bh(WRITE, bh);
1238 nr_underway++;
1239 }
1240 bh = next;
1241 } while (bh != head);
1242 unlock_page(page);
1243
1244 err = 0;
1245done:
1246 if (nr_underway == 0) {
1247 /*
1248 * The page was marked dirty, but the buffers were
1249 * clean. Someone wrote them back by hand with
1250 * ll_rw_block/submit_bh. A rare case.
1251 */
1252 int uptodate = 1;
1253 do {
1254 if (!buffer_uptodate(bh)) {
1255 uptodate = 0;
1256 break;
1257 }
1258 bh = bh->b_this_page;
1259 } while (bh != head);
1260 if (uptodate)
1261 SetPageUptodate(page);
1262 end_page_writeback(page);
1263 /*
1264 * The page and buffer_heads can be released at any time from
1265 * here on.
1266 */
1267 wbc->pages_skipped++; /* We didn't write this page */
1268 }
1269 return err;
1270
1271recover:
1272 /*
1273 * ENOSPC, or some other error. We may already have added some
1274 * blocks to the file, so we need to write these out to avoid
1275 * exposing stale data.
1276 * The page is currently locked and not marked for writeback
1277 */
1278 bh = head;
1279 /* Recovery: lock and submit the mapped buffers */
1280 do {
1281 if (buffer_mapped(bh) && buffer_dirty(bh)) {
1282 lock_buffer(bh);
1283 mark_buffer_async_write(bh);
1284 } else {
1285 /*
1286 * The buffer may have been set dirty during
1287 * attachment to a dirty page.
1288 */
1289 clear_buffer_dirty(bh);
1290 }
1291 } while ((bh = bh->b_this_page) != head);
1292 SetPageError(page);
1293 BUG_ON(PageWriteback(page));
1294 set_page_writeback(page);
1295 do {
1296 struct buffer_head *next = bh->b_this_page;
1297 if (buffer_async_write(bh)) {
1298 clear_buffer_dirty(bh);
1299 submit_bh(WRITE, bh);
1300 nr_underway++;
1301 }
1302 bh = next;
1303 } while (bh != head);
1304 unlock_page(page);
1305 goto done;
1306}
1307
1308/*
1309 * The generic ->writepage function for buffer-backed address_spaces
1310 */
dee26a9f
CM		 1311static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
1312{
236454df
CM		 1313 struct inode * const inode = page->mapping->host;
1314 loff_t i_size = i_size_read(inode);
1315 const pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
1316 unsigned offset;
1317 void *kaddr;
1318
1319 /* Is the page fully inside i_size? */
1320 if (page->index < end_index)
1321 return __btrfs_write_full_page(inode, page, wbc);
1322
1323 /* Is the page fully outside i_size? (truncate in progress) */
1324 offset = i_size & (PAGE_CACHE_SIZE-1);
1325 if (page->index >= end_index+1 || !offset) {
1326 /*
1327 * The page may have dirty, unmapped buffers. For example,
1328 * they may have been added in ext3_writepage(). Make them
1329 * freeable here, so the page does not leak.
1330 */
1331 block_invalidatepage(page, 0);
1332 unlock_page(page);
1333 return 0; /* don't care */
1334 }
1335
1336 /*
1337 * The page straddles i_size. It must be zeroed out on each and every
1338 * writepage invokation because it may be mmapped. "A file is mapped
1339 * in multiples of the page size. For a file that is not a multiple of
1340 * the page size, the remaining memory is zeroed when mapped, and
1341 * writes to that region are not written out to the file."
1342 */
1343 kaddr = kmap_atomic(page, KM_USER0);
1344 memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
1345 flush_dcache_page(page);
1346 kunmap_atomic(kaddr, KM_USER0);
1347 return __btrfs_write_full_page(inode, page, wbc);
dee26a9f 1348}
d561c025 1349
f4b9aa8d
CM		 1350static void btrfs_truncate(struct inode *inode)
1351{
d6e4a428 1352 struct btrfs_root *root = BTRFS_I(inode)->root;
f4b9aa8d
CM		 1353 int ret;
1354 struct btrfs_trans_handle *trans;
1355
1356 if (!S_ISREG(inode->i_mode))
1357 return;
1358 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
1359 return;
1360
e8f05c45 1361 nobh_truncate_page(inode->i_mapping, inode->i_size);
f4b9aa8d
CM		 1362
1363 /* FIXME, add redo link to tree so we don't leak on crash */
1364 mutex_lock(&root->fs_info->fs_mutex);
1365 trans = btrfs_start_transaction(root, 1);
1366 ret = btrfs_truncate_in_trans(trans, root, inode);
1367 BUG_ON(ret);
1368 ret = btrfs_end_transaction(trans, root);
1369 BUG_ON(ret);
1370 mutex_unlock(&root->fs_info->fs_mutex);
1371 mark_inode_dirty(inode);
1372}
1373
236454df
CM		 1374/*
1375 * Make sure any changes to nobh_commit_write() are reflected in
1376 * nobh_truncate_page(), since it doesn't call commit_write().
1377 */
1378static int btrfs_commit_write(struct file *file, struct page *page,
1379 unsigned from, unsigned to)
1380{
1381 struct inode *inode = page->mapping->host;
1382 struct buffer_head *bh;
1383 loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
1384
1385 SetPageUptodate(page);
1386 bh = page_buffers(page);
1387 if (buffer_mapped(bh) && bh->b_blocknr != 0) {
1388 set_page_dirty(page);
1389 }
1390 if (pos > inode->i_size) {
1391 i_size_write(inode, pos);
1392 mark_inode_dirty(inode);
1393 }
1394 return 0;
1395}
1396
75dfe396
CM		 1397static int btrfs_copy_from_user(loff_t pos, int num_pages, int write_bytes,
1398 struct page **prepared_pages,
1399 const char __user * buf)
1400{
1401 long page_fault = 0;
1402 int i;
1403 int offset = pos & (PAGE_CACHE_SIZE - 1);
1404
1405 for (i = 0; i < num_pages && write_bytes > 0; i++, offset = 0) {
1406 size_t count = min_t(size_t,
1407 PAGE_CACHE_SIZE - offset, write_bytes);
1408 struct page *page = prepared_pages[i];
1409 fault_in_pages_readable(buf, count);
1410
1411 /* Copy data from userspace to the current page */
1412 kmap(page);
1413 page_fault = __copy_from_user(page_address(page) + offset,
1414 buf, count);
1415 /* Flush processor's dcache for this page */
1416 flush_dcache_page(page);
1417 kunmap(page);
1418 buf += count;
1419 write_bytes -= count;
1420
1421 if (page_fault)
1422 break;
1423 }
1424 return page_fault ? -EFAULT : 0;
1425}
1426
1427static void btrfs_drop_pages(struct page **pages, size_t num_pages)
1428{
1429 size_t i;
1430 for (i = 0; i < num_pages; i++) {
1431 if (!pages[i])
1432 break;
1433 unlock_page(pages[i]);
1434 mark_page_accessed(pages[i]);
1435 page_cache_release(pages[i]);
1436 }
1437}
1438static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
1439 struct btrfs_root *root,
1440 struct file *file,
1441 struct page **pages,
1442 size_t num_pages,
1443 loff_t pos,
1444 size_t write_bytes)
1445{
1446 int i;
1447 int offset;
1448 int err = 0;
1449 int ret;
1450 int this_write;
f254e52c 1451 struct inode *inode = file->f_path.dentry->d_inode;
236454df
CM		 1452 struct buffer_head *bh;
1453 struct btrfs_file_extent_item *ei;
75dfe396
CM		 1454
1455 for (i = 0; i < num_pages; i++) {
1456 offset = pos & (PAGE_CACHE_SIZE -1);
1457 this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
f254e52c
CM		 1458 /* FIXME, one block at a time */
1459
1460 mutex_lock(&root->fs_info->fs_mutex);
1461 trans = btrfs_start_transaction(root, 1);
236454df
CM		 1462
1463 bh = page_buffers(pages[i]);
1464 if (buffer_mapped(bh) && bh->b_blocknr == 0) {
1465 struct btrfs_key key;
1466 struct btrfs_path *path;
1467 char *ptr;
1468 u32 datasize;
1469
1470 path = btrfs_alloc_path();
1471 BUG_ON(!path);
1472 key.objectid = inode->i_ino;
1473 key.offset = pages[i]->index << PAGE_CACHE_SHIFT;
1474 key.flags = 0;
1475 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
1476 BUG_ON(write_bytes >= PAGE_CACHE_SIZE);
1477 datasize = offset +
1478 btrfs_file_extent_calc_inline_size(write_bytes);
1479 ret = btrfs_insert_empty_item(trans, root, path, &key,
1480 datasize);
1481 BUG_ON(ret);
1482 ei = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
1483 path->slots[0], struct btrfs_file_extent_item);
1484 btrfs_set_file_extent_generation(ei, trans->transid);
1485 btrfs_set_file_extent_type(ei,
1486 BTRFS_FILE_EXTENT_INLINE);
1487 ptr = btrfs_file_extent_inline_start(ei);
1488 memcpy(ptr, bh->b_data, offset + write_bytes);
1489 mark_buffer_dirty(path->nodes[0]);
1490 btrfs_free_path(path);
1491 } else {
1492 btrfs_csum_file_block(trans, root, inode->i_ino,
f254e52c
CM		 1493 pages[i]->index << PAGE_CACHE_SHIFT,
1494 kmap(pages[i]), PAGE_CACHE_SIZE);
236454df
CM		 1495 kunmap(pages[i]);
1496 }
f254e52c
CM		 1497 SetPageChecked(pages[i]);
1498 ret = btrfs_end_transaction(trans, root);
1499 BUG_ON(ret);
1500 mutex_unlock(&root->fs_info->fs_mutex);
1501
236454df 1502 ret = btrfs_commit_write(file, pages[i], offset,
75dfe396
CM		 1503 offset + this_write);
1504 pos += this_write;
1505 if (ret) {
1506 err = ret;
1507 goto failed;
1508 }
1509 WARN_ON(this_write > write_bytes);
1510 write_bytes -= this_write;
1511 }
1512failed:
1513 return err;
1514}
1515
b18c6685
CM		 1516static int drop_extents(struct btrfs_trans_handle *trans,
1517 struct btrfs_root *root,
1518 struct inode *inode,
1519 u64 start, u64 end)
1520{
1521 int ret;
1522 struct btrfs_key key;
1523 struct btrfs_leaf *leaf;
1524 int slot;
1525 struct btrfs_file_extent_item *extent;
236454df 1526 u64 extent_end = 0;
b18c6685
CM		 1527 int keep;
1528 struct btrfs_file_extent_item old;
1529 struct btrfs_path *path;
1530 u64 search_start = start;
1531 int bookend;
236454df
CM		 1532 int found_type;
1533 int found_extent;
1534 int found_inline;
1535
b18c6685
CM		 1536 path = btrfs_alloc_path();
1537 if (!path)
1538 return -ENOMEM;
a429e513
CM		 1539 while(1) {
1540 btrfs_release_path(root, path);
1541 ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
1542 search_start, -1);
1543 if (ret < 0)
70b2befd 1544 goto out;
a429e513
CM		 1545 if (ret > 0) {
1546 if (path->slots[0] == 0) {
236454df 1547 ret = 0;
a429e513
CM		 1548 goto out;
1549 }
1550 path->slots[0]--;
70b2befd 1551 }
b18c6685
CM		 1552 keep = 0;
1553 bookend = 0;
236454df
CM		 1554 found_extent = 0;
1555 found_inline = 0;
1556 extent = NULL;
b18c6685
CM		 1557 leaf = btrfs_buffer_leaf(path->nodes[0]);
1558 slot = path->slots[0];
1559 btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
b18c6685
CM		 1560 if (key.offset >= end || key.objectid != inode->i_ino) {
1561 ret = 0;
1562 goto out;
1563 }
236454df
CM		 1564 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) {
1565 ret = 0;
1566 goto out;
1567 }
1568 extent = btrfs_item_ptr(leaf, slot,
1569 struct btrfs_file_extent_item);
1570 found_type = btrfs_file_extent_type(extent);
1571 if (found_type == BTRFS_FILE_EXTENT_REG) {
1572 extent_end = key.offset +
1573 (btrfs_file_extent_num_blocks(extent) <<
1574 inode->i_blkbits);
1575 found_extent = 1;
1576 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
1577 found_inline = 1;
1578 extent_end = key.offset +
1579 btrfs_file_extent_inline_len(leaf->items + slot);
1580 }
1581
1582 if (!found_extent && !found_inline) {
1583 ret = 0;
a429e513 1584 goto out;
236454df
CM		 1585 }
1586
1587 if (search_start >= extent_end) {
1588 ret = 0;
a429e513 1589 goto out;
236454df
CM		 1590 }
1591
a429e513 1592 search_start = extent_end;
b18c6685
CM		 1593
1594 if (end < extent_end && end >= key.offset) {
236454df
CM		 1595 if (found_extent) {
1596 memcpy(&old, extent, sizeof(old));
1597 ret = btrfs_inc_extent_ref(trans, root,
1598 btrfs_file_extent_disk_blocknr(&old),
1599 btrfs_file_extent_disk_num_blocks(&old));
1600 BUG_ON(ret);
1601 }
1602 WARN_ON(found_inline);
b18c6685
CM		 1603 bookend = 1;
1604 }
1605
1606 if (start > key.offset) {
1607 u64 new_num;
a429e513 1608 u64 old_num;
b18c6685
CM		 1609 /* truncate existing extent */
1610 keep = 1;
1611 WARN_ON(start & (root->blocksize - 1));
236454df
CM		 1612 if (found_extent) {
1613 new_num = (start - key.offset) >>
1614 inode->i_blkbits;
1615 old_num = btrfs_file_extent_num_blocks(extent);
1616 inode->i_blocks -= (old_num - new_num) << 3;
1617 btrfs_set_file_extent_num_blocks(extent,
1618 new_num);
1619 mark_buffer_dirty(path->nodes[0]);
1620 } else {
1621 WARN_ON(1);
1622 /*
1623 ret = btrfs_truncate_item(trans, root, path,
1624 start - key.offset);
1625 BUG_ON(ret);
1626 */
1627 }
b18c6685
CM		 1628 }
1629 if (!keep) {
236454df
CM		 1630 u64 disk_blocknr = 0;
1631 u64 disk_num_blocks = 0;
1632 u64 extent_num_blocks = 0;
1633 if (found_extent) {
1634 disk_blocknr =
1635 btrfs_file_extent_disk_blocknr(extent);
1636 disk_num_blocks =
1637 btrfs_file_extent_disk_num_blocks(extent);
1638 extent_num_blocks =
1639 btrfs_file_extent_num_blocks(extent);
1640 }
b18c6685
CM		 1641 ret = btrfs_del_item(trans, root, path);
1642 BUG_ON(ret);
1643 btrfs_release_path(root, path);
236454df
CM		 1644 if (found_extent) {
1645 inode->i_blocks -=
1646 btrfs_file_extent_num_blocks(extent) << 3;
1647 ret = btrfs_free_extent(trans, root,
1648 disk_blocknr,
1649 disk_num_blocks, 0);
1650 }
b18c6685
CM		 1651
1652 BUG_ON(ret);
1653 if (!bookend && search_start >= end) {
1654 ret = 0;
1655 goto out;
1656 }
1657 if (!bookend)
a429e513 1658 continue;
b18c6685 1659 }
236454df 1660 if (bookend && found_extent) {
b18c6685
CM		 1661 /* create bookend */
1662 struct btrfs_key ins;
b18c6685
CM		 1663 ins.objectid = inode->i_ino;
1664 ins.offset = end;
1665 ins.flags = 0;
1666 btrfs_set_key_type(&ins, BTRFS_EXTENT_DATA_KEY);
1667
1668 btrfs_release_path(root, path);
b18c6685
CM		 1669 ret = btrfs_insert_empty_item(trans, root, path, &ins,
1670 sizeof(*extent));
1671 BUG_ON(ret);
1672 extent = btrfs_item_ptr(
1673 btrfs_buffer_leaf(path->nodes[0]),
1674 path->slots[0],
1675 struct btrfs_file_extent_item);
1676 btrfs_set_file_extent_disk_blocknr(extent,
1677 btrfs_file_extent_disk_blocknr(&old));
1678 btrfs_set_file_extent_disk_num_blocks(extent,
1679 btrfs_file_extent_disk_num_blocks(&old));
1680
1681 btrfs_set_file_extent_offset(extent,
1682 btrfs_file_extent_offset(&old) +
1683 ((end - key.offset) >> inode->i_blkbits));
1684 WARN_ON(btrfs_file_extent_num_blocks(&old) <
1685 (end - key.offset) >> inode->i_blkbits);
1686 btrfs_set_file_extent_num_blocks(extent,
1687 btrfs_file_extent_num_blocks(&old) -
1688 ((end - key.offset) >> inode->i_blkbits));
1689
236454df
CM		 1690 btrfs_set_file_extent_type(extent,
1691 BTRFS_FILE_EXTENT_REG);
b18c6685
CM		 1692 btrfs_set_file_extent_generation(extent,
1693 btrfs_file_extent_generation(&old));
b18c6685 1694 btrfs_mark_buffer_dirty(path->nodes[0]);
a429e513
CM		 1695 inode->i_blocks +=
1696 btrfs_file_extent_num_blocks(extent) << 3;
b18c6685 1697 ret = 0;
70b2befd 1698 goto out;
b18c6685 1699 }
b18c6685 1700 }
b18c6685 1701out:
b18c6685
CM		 1702 btrfs_free_path(path);
1703 return ret;
1704}
1705
1706static int prepare_pages(struct btrfs_root *root,
75dfe396
CM		 1707 struct file *file,
1708 struct page **pages,
1709 size_t num_pages,
1710 loff_t pos,
2932f3ec
CM		 1711 unsigned long first_index,
1712 unsigned long last_index,
6567e837
CM		 1713 size_t write_bytes,
1714 u64 alloc_extent_start)
75dfe396
CM		 1715{
1716 int i;
1717 unsigned long index = pos >> PAGE_CACHE_SHIFT;
1718 struct inode *inode = file->f_path.dentry->d_inode;
1719 int offset;
1720 int err = 0;
75dfe396 1721 int this_write;
6567e837
CM		 1722 struct buffer_head *bh;
1723 struct buffer_head *head;
75dfe396
CM		 1724 loff_t isize = i_size_read(inode);
1725
1726 memset(pages, 0, num_pages * sizeof(struct page *));
1727
1728 for (i = 0; i < num_pages; i++) {
1729 pages[i] = grab_cache_page(inode->i_mapping, index + i);
1730 if (!pages[i]) {
1731 err = -ENOMEM;
1732 goto failed_release;
1733 }
1734 offset = pos & (PAGE_CACHE_SIZE -1);
1735 this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
6567e837
CM		 1736 create_empty_buffers(pages[i], root->fs_info->sb->s_blocksize,
1737 (1 << BH_Uptodate));
1738 head = page_buffers(pages[i]);
1739 bh = head;
1740 do {
1741 err = btrfs_map_bh_to_logical(root, bh,
1742 alloc_extent_start);
1743 BUG_ON(err);
1744 if (err)
1745 goto failed_truncate;
1746 bh = bh->b_this_page;
236454df
CM		 1747 if (alloc_extent_start)
1748 alloc_extent_start++;
6567e837 1749 } while (bh != head);
75dfe396 1750 pos += this_write;
75dfe396
CM		 1751 WARN_ON(this_write > write_bytes);
1752 write_bytes -= this_write;
1753 }
1754 return 0;
1755
1756failed_release:
1757 btrfs_drop_pages(pages, num_pages);
1758 return err;
1759
1760failed_truncate:
1761 btrfs_drop_pages(pages, num_pages);
1762 if (pos > isize)
1763 vmtruncate(inode, isize);
1764 return err;
1765}
1766
1767static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
1768 size_t count, loff_t *ppos)
1769{
1770 loff_t pos;
1771 size_t num_written = 0;
1772 int err = 0;
1773 int ret = 0;
75dfe396 1774 struct inode *inode = file->f_path.dentry->d_inode;
d6e4a428 1775 struct btrfs_root *root = BTRFS_I(inode)->root;
b18c6685 1776 struct page *pages[8];
a429e513 1777 struct page *pinned[2] = { NULL, NULL };
2932f3ec
CM		 1778 unsigned long first_index;
1779 unsigned long last_index;
6567e837
CM		 1780 u64 start_pos;
1781 u64 num_blocks;
1782 u64 alloc_extent_start;
6567e837 1783 struct btrfs_trans_handle *trans;
b18c6685 1784 struct btrfs_key ins;
75dfe396
CM		 1785
1786 if (file->f_flags & O_DIRECT)
1787 return -EINVAL;
1788 pos = *ppos;
75dfe396
CM		 1789 vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
1790 current->backing_dev_info = inode->i_mapping->backing_dev_info;
1791 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
1792 if (err)
1793 goto out;
1794 if (count == 0)
1795 goto out;
1796 err = remove_suid(file->f_path.dentry);
1797 if (err)
1798 goto out;
1799 file_update_time(file);
a429e513
CM		 1800
1801 start_pos = pos & ~((u64)PAGE_CACHE_SIZE - 1);
1802 num_blocks = (count + pos - start_pos + root->blocksize - 1) >>
1803 inode->i_blkbits;
1804
75dfe396 1805 mutex_lock(&inode->i_mutex);
2932f3ec
CM		 1806 first_index = pos >> PAGE_CACHE_SHIFT;
1807 last_index = (pos + count) >> PAGE_CACHE_SHIFT;
6567e837 1808
a429e513
CM		 1809 if ((first_index << PAGE_CACHE_SHIFT) < inode->i_size &&
1810 (pos & (PAGE_CACHE_SIZE - 1))) {
1811 pinned[0] = grab_cache_page(inode->i_mapping, first_index);
1812 if (!PageUptodate(pinned[0])) {
1813 ret = mpage_readpage(pinned[0], btrfs_get_block);
1814 BUG_ON(ret);
1815 } else {
1816 unlock_page(pinned[0]);
1817 }
1818 }
1819 if (first_index != last_index &&
1820 (last_index << PAGE_CACHE_SHIFT) < inode->i_size &&
1821 (count & (PAGE_CACHE_SIZE - 1))) {
1822 pinned[1] = grab_cache_page(inode->i_mapping, last_index);
1823 if (!PageUptodate(pinned[1])) {
1824 ret = mpage_readpage(pinned[1], btrfs_get_block);
1825 BUG_ON(ret);
1826 } else {
1827 unlock_page(pinned[1]);
1828 }
1829 }
1830
6567e837
CM		 1831 mutex_lock(&root->fs_info->fs_mutex);
1832 trans = btrfs_start_transaction(root, 1);
1833 if (!trans) {
1834 err = -ENOMEM;
b18c6685 1835 mutex_unlock(&root->fs_info->fs_mutex);
6567e837
CM		 1836 goto out_unlock;
1837 }
a429e513
CM		 1838 /* FIXME blocksize != 4096 */
1839 inode->i_blocks += num_blocks << 3;
b18c6685 1840 if (start_pos < inode->i_size) {
a429e513 1841 /* FIXME blocksize != pagesize */
b18c6685
CM		 1842 ret = drop_extents(trans, root, inode,
1843 start_pos,
1844 (pos + count + root->blocksize -1) &
a429e513 1845 ~((u64)root->blocksize - 1));
236454df 1846 BUG_ON(ret);
b18c6685 1847 }
236454df
CM		 1848 if (inode->i_size >= PAGE_CACHE_SIZE || pos + count < inode->i_size ||
1849 pos + count - start_pos > BTRFS_MAX_INLINE_DATA_SIZE(root)) {
1850 ret = btrfs_alloc_extent(trans, root, num_blocks, 1,
b18c6685 1851 (u64)-1, &ins);
236454df
CM		 1852 BUG_ON(ret);
1853 ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
b18c6685 1854 start_pos, ins.objectid, ins.offset);
236454df
CM		 1855 BUG_ON(ret);
1856 } else {
1857 ins.offset = 0;
1858 ins.objectid = 0;
1859 }
6567e837 1860 BUG_ON(ret);
b18c6685
CM		 1861 alloc_extent_start = ins.objectid;
1862 ret = btrfs_end_transaction(trans, root);
6567e837
CM		 1863 mutex_unlock(&root->fs_info->fs_mutex);
1864
75dfe396
CM		 1865 while(count > 0) {
1866 size_t offset = pos & (PAGE_CACHE_SIZE - 1);
1867 size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset);
1868 size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
1869 PAGE_CACHE_SHIFT;
b18c6685
CM		 1870
1871 memset(pages, 0, sizeof(pages));
1872 ret = prepare_pages(root, file, pages, num_pages,
6567e837
CM		 1873 pos, first_index, last_index,
1874 write_bytes, alloc_extent_start);
75dfe396 1875 BUG_ON(ret);
b18c6685 1876
6567e837 1877 /* FIXME blocks != pagesize */
236454df
CM		 1878 if (alloc_extent_start)
1879 alloc_extent_start += num_pages;
75dfe396
CM		 1880 ret = btrfs_copy_from_user(pos, num_pages,
1881 write_bytes, pages, buf);
1882 BUG_ON(ret);
1883
f254e52c 1884 ret = dirty_and_release_pages(NULL, root, file, pages,
70b2befd 1885 num_pages, pos, write_bytes);
75dfe396
CM		 1886 BUG_ON(ret);
1887 btrfs_drop_pages(pages, num_pages);
1888
75dfe396
CM		 1889 buf += write_bytes;
1890 count -= write_bytes;
1891 pos += write_bytes;
1892 num_written += write_bytes;
1893
1894 balance_dirty_pages_ratelimited(inode->i_mapping);
1895 cond_resched();
1896 }
6567e837 1897out_unlock:
75dfe396
CM		 1898 mutex_unlock(&inode->i_mutex);
1899out:
a429e513
CM		 1900 if (pinned[0])
1901 page_cache_release(pinned[0]);
1902 if (pinned[1])
1903 page_cache_release(pinned[1]);
75dfe396
CM		 1904 *ppos = pos;
1905 current->backing_dev_info = NULL;
a429e513 1906 mark_inode_dirty(inode);
75dfe396
CM		 1907 return num_written ? num_written : err;
1908}
1909
e8f05c45 1910#if 0
df24a2b9
CM		 1911static ssize_t inline_one_page(struct btrfs_root *root, struct inode *inode,
1912 struct page *page, loff_t pos,
1913 size_t offset, size_t write_bytes)
1914{
1915 struct btrfs_path *path;
1916 struct btrfs_trans_handle *trans;
1917 struct btrfs_key key;
1918 struct btrfs_leaf *leaf;
1919 struct btrfs_key found_key;
1920 int ret;
1921 size_t copy_size = 0;
1922 char *dst = NULL;
1923 int err = 0;
1924 size_t num_written = 0;
1925
1926 path = btrfs_alloc_path();
1927 BUG_ON(!path);
1928 mutex_lock(&root->fs_info->fs_mutex);
1929 trans = btrfs_start_transaction(root, 1);
1930 key.objectid = inode->i_ino;
1931 key.flags = 0;
1932 btrfs_set_key_type(&key, BTRFS_INLINE_DATA_KEY);
1933
1934again:
1935 key.offset = pos;
1936 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1937 if (ret < 0) {
1938 err = ret;
1939 goto out;
1940 }
1941 if (ret == 0) {
1942 leaf = btrfs_buffer_leaf(path->nodes[0]);
1943 btrfs_disk_key_to_cpu(&found_key,
1944 &leaf->items[path->slots[0]].key);
1945 copy_size = btrfs_item_size(leaf->items + path->slots[0]);
1946 dst = btrfs_item_ptr(leaf, path->slots[0], char);
1947 copy_size = min(write_bytes, copy_size);
1948 goto copyit;
1949 } else {
1950 int slot = path->slots[0];
1951 if (slot > 0) {
1952 slot--;
1953 }
1954 // FIXME find max key
1955 leaf = btrfs_buffer_leaf(path->nodes[0]);
1956 btrfs_disk_key_to_cpu(&found_key,
1957 &leaf->items[slot].key);
1958 if (found_key.objectid != inode->i_ino)
1959 goto insert;
1960 if (btrfs_key_type(&found_key) != BTRFS_INLINE_DATA_KEY)
1961 goto insert;
1962 copy_size = btrfs_item_size(leaf->items + slot);
1963 if (found_key.offset + copy_size <= pos)
1964 goto insert;
1965 dst = btrfs_item_ptr(leaf, path->slots[0], char);
1966 dst += pos - found_key.offset;
1967 copy_size = copy_size - (pos - found_key.offset);
1968 BUG_ON(copy_size < 0);
1969 copy_size = min(write_bytes, copy_size);
1970 WARN_ON(copy_size == 0);
1971 goto copyit;
1972 }
1973insert:
1974 btrfs_release_path(root, path);
d4dbff95
CM		 1975 copy_size = min(write_bytes,
1976 (size_t)BTRFS_LEAF_DATA_SIZE(root) -
1977 sizeof(struct btrfs_item) * 4);
df24a2b9
CM		 1978 ret = btrfs_insert_empty_item(trans, root, path, &key, copy_size);
1979 BUG_ON(ret);
1980 dst = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
1981 path->slots[0], char);
1982copyit:
1983 WARN_ON(copy_size == 0);
1984 WARN_ON(dst + copy_size >
1985 btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
1986 path->slots[0], char) +
1987 btrfs_item_size(btrfs_buffer_leaf(path->nodes[0])->items +
1988 path->slots[0]));
1989 btrfs_memcpy(root, path->nodes[0]->b_data, dst,
1990 page_address(page) + offset, copy_size);
1991 mark_buffer_dirty(path->nodes[0]);
1992 btrfs_release_path(root, path);
1993 pos += copy_size;
1994 offset += copy_size;
1995 num_written += copy_size;
1996 write_bytes -= copy_size;
1997 if (write_bytes)
1998 goto again;
1999out:
2000 btrfs_free_path(path);
2001 ret = btrfs_end_transaction(trans, root);
2002 BUG_ON(ret);
2003 mutex_unlock(&root->fs_info->fs_mutex);
2004 return num_written ? num_written : err;
2005}
2006
2007static ssize_t btrfs_file_inline_write(struct file *file,
2008 const char __user *buf,
2009 size_t count, loff_t *ppos)
2010{
2011 loff_t pos;
2012 size_t num_written = 0;
2013 int err = 0;
2014 int ret = 0;
2015 struct inode *inode = file->f_path.dentry->d_inode;
d6e4a428 2016 struct btrfs_root *root = BTRFS_I(inode)->root;
df24a2b9
CM		 2017 unsigned long page_index;
2018
2019 if (file->f_flags & O_DIRECT)
2020 return -EINVAL;
2021 pos = *ppos;
2022
2023 vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
2024 current->backing_dev_info = inode->i_mapping->backing_dev_info;
2025 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
2026 if (err)
2027 goto out;
2028 if (count == 0)
2029 goto out;
2030 err = remove_suid(file->f_path.dentry);
2031 if (err)
2032 goto out;
2033 file_update_time(file);
2034 mutex_lock(&inode->i_mutex);
2035 while(count > 0) {
2036 size_t offset = pos & (PAGE_CACHE_SIZE - 1);
2037 size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset);
2038 struct page *page;
2039
2040 page_index = pos >> PAGE_CACHE_SHIFT;
2041 page = grab_cache_page(inode->i_mapping, page_index);
2042 if (!PageUptodate(page)) {
2043 ret = mpage_readpage(page, btrfs_get_block);
2044 BUG_ON(ret);
2045 lock_page(page);
2046 }
2047 ret = btrfs_copy_from_user(pos, 1,
2048 write_bytes, &page, buf);
2049 BUG_ON(ret);
2050 write_bytes = inline_one_page(root, inode, page, pos,
2051 offset, write_bytes);
2052 SetPageUptodate(page);
2053 if (write_bytes > 0 && pos + write_bytes > inode->i_size) {
2054 i_size_write(inode, pos + write_bytes);
2055 mark_inode_dirty(inode);
2056 }
2057 page_cache_release(page);
2058 unlock_page(page);
2059 if (write_bytes < 0)
2060 goto out_unlock;
2061 buf += write_bytes;
2062 count -= write_bytes;
2063 pos += write_bytes;
2064 num_written += write_bytes;
2065
2066 balance_dirty_pages_ratelimited(inode->i_mapping);
2067 cond_resched();
2068 }
2069out_unlock:
2070 mutex_unlock(&inode->i_mutex);
2071out:
2072 *ppos = pos;
2073 current->backing_dev_info = NULL;
2074 return num_written ? num_written : err;
2075}
e8f05c45 2076#endif
df24a2b9 2077
f254e52c
CM		 2078static int btrfs_read_actor(read_descriptor_t *desc, struct page *page,
2079 unsigned long offset, unsigned long size)
2080{
2081 char *kaddr;
2082 unsigned long left, count = desc->count;
d6e4a428 2083 struct inode *inode = page->mapping->host;
f254e52c
CM		 2084
2085 if (size > count)
2086 size = count;
2087
2088 if (!PageChecked(page)) {
2089 /* FIXME, do it per block */
d6e4a428 2090 struct btrfs_root *root = BTRFS_I(inode)->root;
236454df 2091
f254e52c 2092 int ret = btrfs_csum_verify_file_block(root,
236454df
CM		 2093 page->mapping->host->i_ino,
2094 page->index << PAGE_CACHE_SHIFT,
2095 kmap(page), PAGE_CACHE_SIZE);
f254e52c
CM		 2096 if (ret) {
2097 printk("failed to verify ino %lu page %lu\n",
2098 page->mapping->host->i_ino,
2099 page->index);
2100 memset(page_address(page), 0, PAGE_CACHE_SIZE);
2101 }
2102 SetPageChecked(page);
2103 kunmap(page);
2104 }
2105 /*
2106 * Faults on the destination of a read are common, so do it before
2107 * taking the kmap.
2108 */
2109 if (!fault_in_pages_writeable(desc->arg.buf, size)) {
2110 kaddr = kmap_atomic(page, KM_USER0);
2111 left = __copy_to_user_inatomic(desc->arg.buf,
2112 kaddr + offset, size);
2113 kunmap_atomic(kaddr, KM_USER0);
2114 if (left == 0)
2115 goto success;
2116 }
2117
2118 /* Do it the slow way */
2119 kaddr = kmap(page);
2120 left = __copy_to_user(desc->arg.buf, kaddr + offset, size);
2121 kunmap(page);
2122
2123 if (left) {
2124 size -= left;
2125 desc->error = -EFAULT;
2126 }
2127success:
2128 desc->count = count - size;
2129 desc->written += size;
2130 desc->arg.buf += size;
2131 return size;
2132}
2133
2134/**
2135 * btrfs_file_aio_read - filesystem read routine
2136 * @iocb: kernel I/O control block
2137 * @iov: io vector request
2138 * @nr_segs: number of segments in the iovec
2139 * @pos: current file position
2140 */
2141static ssize_t btrfs_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
2142 unsigned long nr_segs, loff_t pos)
2143{
2144 struct file *filp = iocb->ki_filp;
2145 ssize_t retval;
2146 unsigned long seg;
2147 size_t count;
2148 loff_t *ppos = &iocb->ki_pos;
2149
2150 count = 0;
2151 for (seg = 0; seg < nr_segs; seg++) {
2152 const struct iovec *iv = &iov[seg];
2153
2154 /*
2155 * If any segment has a negative length, or the cumulative
2156 * length ever wraps negative then return -EINVAL.
2157 */
2158 count += iv->iov_len;
2159 if (unlikely((ssize_t)(count|iv->iov_len) < 0))
2160 return -EINVAL;
2161 if (access_ok(VERIFY_WRITE, iv->iov_base, iv->iov_len))
2162 continue;
2163 if (seg == 0)
2164 return -EFAULT;
2165 nr_segs = seg;
2166 count -= iv->iov_len; /* This segment is no good */
2167 break;
2168 }
2169 retval = 0;
2170 if (count) {
2171 for (seg = 0; seg < nr_segs; seg++) {
2172 read_descriptor_t desc;
2173
2174 desc.written = 0;
2175 desc.arg.buf = iov[seg].iov_base;
2176 desc.count = iov[seg].iov_len;
2177 if (desc.count == 0)
2178 continue;
2179 desc.error = 0;
2180 do_generic_file_read(filp, ppos, &desc,
2181 btrfs_read_actor);
2182 retval += desc.written;
2183 if (desc.error) {
2184 retval = retval ?: desc.error;
2185 break;
2186 }
2187 }
2188 }
2189 return retval;
2190}
2191
2619ba1f
CM		 2192static int create_subvol(struct btrfs_root *root, char *name, int namelen)
2193{
2194 struct btrfs_trans_handle *trans;
2195 struct btrfs_key key;
2196 struct btrfs_root_item root_item;
2197 struct btrfs_inode_item *inode_item;
2198 struct buffer_head *subvol;
2199 struct btrfs_leaf *leaf;
2200 struct btrfs_root *new_root;
2201 struct inode *inode;
2202 int ret;
2203 u64 objectid;
2204 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
2205
2206 mutex_lock(&root->fs_info->fs_mutex);
2207 trans = btrfs_start_transaction(root, 1);
2208 BUG_ON(!trans);
2209
2210 subvol = btrfs_alloc_free_block(trans, root);
2211 leaf = btrfs_buffer_leaf(subvol);
2212 btrfs_set_header_nritems(&leaf->header, 0);
2213 btrfs_set_header_level(&leaf->header, 0);
7eccb903 2214 btrfs_set_header_blocknr(&leaf->header, bh_blocknr(subvol));
2619ba1f
CM		 2215 btrfs_set_header_generation(&leaf->header, trans->transid);
2216 memcpy(leaf->header.fsid, root->fs_info->disk_super->fsid,
2217 sizeof(leaf->header.fsid));
2218
2219 inode_item = &root_item.inode;
2220 memset(inode_item, 0, sizeof(*inode_item));
2221 btrfs_set_inode_generation(inode_item, 1);
2222 btrfs_set_inode_size(inode_item, 3);
2223 btrfs_set_inode_nlink(inode_item, 1);
2224 btrfs_set_inode_nblocks(inode_item, 1);
2225 btrfs_set_inode_mode(inode_item, S_IFDIR | 0755);
2226
7eccb903 2227 btrfs_set_root_blocknr(&root_item, bh_blocknr(subvol));
2619ba1f
CM		 2228 btrfs_set_root_refs(&root_item, 1);
2229
2230 mark_buffer_dirty(subvol);
2231 brelse(subvol);
2232 subvol = NULL;
2233
2234 ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
2235 0, &objectid);
2236 BUG_ON(ret);
2237
2238 btrfs_set_root_dirid(&root_item, new_dirid);
2239
2240 key.objectid = objectid;
2241 key.offset = 1;
2242 key.flags = 0;
2243 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
2244 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
2245 &root_item);
2246 BUG_ON(ret);
2247
2248 /*
2249 * insert the directory item
2250 */
2251 key.offset = (u64)-1;
2252 ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
2253 name, namelen,
2254 root->fs_info->sb->s_root->d_inode->i_ino,
2255 &key, 0);
2256 BUG_ON(ret);
2257
2258 ret = btrfs_commit_transaction(trans, root);
2259 BUG_ON(ret);
2260
2261 new_root = btrfs_read_fs_root(root->fs_info, &key);
2262 BUG_ON(!new_root);
2263
2264 trans = btrfs_start_transaction(new_root, 1);
2265 BUG_ON(!trans);
2266
2267 inode = btrfs_new_inode(trans, new_root, new_dirid, S_IFDIR | 0700);
2268 inode->i_op = &btrfs_dir_inode_operations;
2269 inode->i_fop = &btrfs_dir_file_operations;
2270
2271 ret = btrfs_make_empty_dir(trans, new_root, new_dirid, new_dirid);
2272 BUG_ON(ret);
2273
2274 inode->i_nlink = 1;
2275 inode->i_size = 6;
2276 ret = btrfs_update_inode(trans, new_root, inode);
2277 BUG_ON(ret);
2278
2279 ret = btrfs_commit_transaction(trans, new_root);
2280 BUG_ON(ret);
2281
2282 iput(inode);
2283
2284 mutex_unlock(&root->fs_info->fs_mutex);
2285 return 0;
2286}
2287
c5739bba
CM		 2288static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
2289{
2290 struct btrfs_trans_handle *trans;
2291 struct btrfs_key key;
2292 struct btrfs_root_item new_root_item;
2293 int ret;
2294 u64 objectid;
2295
2619ba1f
CM		 2296 if (!root->ref_cows)
2297 return -EINVAL;
2298
c5739bba
CM		 2299 mutex_lock(&root->fs_info->fs_mutex);
2300 trans = btrfs_start_transaction(root, 1);
2301 BUG_ON(!trans);
2302
2303 ret = btrfs_update_inode(trans, root, root->inode);
2304 BUG_ON(ret);
2305
1b05da2e
CM		 2306 ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
2307 0, &objectid);
c5739bba
CM		 2308 BUG_ON(ret);
2309
c5739bba
CM		 2310 memcpy(&new_root_item, &root->root_item,
2311 sizeof(new_root_item));
2312
c5739bba
CM		 2313 key.objectid = objectid;
2314 key.offset = 1;
2315 key.flags = 0;
2316 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
7eccb903 2317 btrfs_set_root_blocknr(&new_root_item, bh_blocknr(root->node));
c5739bba
CM		 2318
2319 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
2320 &new_root_item);
2321 BUG_ON(ret);
2322
c5739bba
CM		 2323 /*
2324 * insert the directory item
2325 */
2326 key.offset = (u64)-1;
2327 ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
2328 name, namelen,
2329 root->fs_info->sb->s_root->d_inode->i_ino,
2330 &key, 0);
2331
2332 BUG_ON(ret);
2333
2334 ret = btrfs_inc_root_ref(trans, root);
2335 BUG_ON(ret);
2336
2337 ret = btrfs_commit_transaction(trans, root);
2338 BUG_ON(ret);
2339 mutex_unlock(&root->fs_info->fs_mutex);
2340 return 0;
2341}
2342
8352d8a4
CM		 2343static int add_disk(struct btrfs_root *root, char *name, int namelen)
2344{
2345 struct block_device *bdev;
2346 struct btrfs_path *path;
2347 struct super_block *sb = root->fs_info->sb;
2348 struct btrfs_root *dev_root = root->fs_info->dev_root;
2349 struct btrfs_trans_handle *trans;
2350 struct btrfs_device_item *dev_item;
2351 struct btrfs_key key;
2352 u16 item_size;
2353 u64 num_blocks;
2354 u64 new_blocks;
b4100d64 2355 u64 device_id;
8352d8a4 2356 int ret;
b4100d64 2357
8352d8a4
CM		 2358printk("adding disk %s\n", name);
2359 path = btrfs_alloc_path();
2360 if (!path)
2361 return -ENOMEM;
2362 num_blocks = btrfs_super_total_blocks(root->fs_info->disk_super);
2363 bdev = open_bdev_excl(name, O_RDWR, sb);
2364 if (IS_ERR(bdev)) {
2365 ret = PTR_ERR(bdev);
2366printk("open bdev excl failed ret %d\n", ret);
2367 goto out_nolock;
2368 }
2369 set_blocksize(bdev, sb->s_blocksize);
2370 new_blocks = bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2371 key.objectid = num_blocks;
2372 key.offset = new_blocks;
2373 key.flags = 0;
2374 btrfs_set_key_type(&key, BTRFS_DEV_ITEM_KEY);
2375
2376 mutex_lock(&dev_root->fs_info->fs_mutex);
2377 trans = btrfs_start_transaction(dev_root, 1);
2378 item_size = sizeof(*dev_item) + namelen;
2379printk("insert empty on %Lu %Lu %u size %d\n", num_blocks, new_blocks, key.flags, item_size);
2380 ret = btrfs_insert_empty_item(trans, dev_root, path, &key, item_size);
2381 if (ret) {
2382printk("insert failed %d\n", ret);
2383 close_bdev_excl(bdev);
2384 if (ret > 0)
2385 ret = -EEXIST;
2386 goto out;
2387 }
2388 dev_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
2389 path->slots[0], struct btrfs_device_item);
2390 btrfs_set_device_pathlen(dev_item, namelen);
2391 memcpy(dev_item + 1, name, namelen);
b4100d64
CM		 2392
2393 device_id = btrfs_super_last_device_id(root->fs_info->disk_super) + 1;
2394 btrfs_set_super_last_device_id(root->fs_info->disk_super, device_id);
2395 btrfs_set_device_id(dev_item, device_id);
8352d8a4
CM		 2396 mark_buffer_dirty(path->nodes[0]);
2397
b4100d64
CM		 2398 ret = btrfs_insert_dev_radix(root, bdev, device_id, num_blocks,
2399 new_blocks);
8352d8a4
CM		 2400
2401 if (!ret) {
2402 btrfs_set_super_total_blocks(root->fs_info->disk_super,
2403 num_blocks + new_blocks);
2404 i_size_write(root->fs_info->btree_inode,
2405 (num_blocks + new_blocks) <<
2406 root->fs_info->btree_inode->i_blkbits);
2407 }
2408
2409out:
2410 ret = btrfs_commit_transaction(trans, dev_root);
2411 BUG_ON(ret);
2412 mutex_unlock(&root->fs_info->fs_mutex);
2413out_nolock:
2414 btrfs_free_path(path);
2415
2416 return ret;
2417}
2418
c5739bba
CM		 2419static int btrfs_ioctl(struct inode *inode, struct file *filp, unsigned int
2420 cmd, unsigned long arg)
2421{
2422 struct btrfs_root *root = BTRFS_I(inode)->root;
2423 struct btrfs_ioctl_vol_args vol_args;
8352d8a4 2424 int ret = 0;
c5739bba 2425 int namelen;
2619ba1f
CM		 2426 struct btrfs_path *path;
2427 u64 root_dirid;
c5739bba 2428
c5739bba
CM		 2429 switch (cmd) {
2430 case BTRFS_IOC_SNAP_CREATE:
2431 if (copy_from_user(&vol_args,
2432 (struct btrfs_ioctl_vol_args __user *)arg,
2433 sizeof(vol_args)))
2434 return -EFAULT;
2435 namelen = strlen(vol_args.name);
2436 if (namelen > BTRFS_VOL_NAME_MAX)
2437 return -EINVAL;
2619ba1f
CM		 2438 path = btrfs_alloc_path();
2439 if (!path)
2440 return -ENOMEM;
2d13d8d0 2441 root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
2619ba1f
CM		 2442 mutex_lock(&root->fs_info->fs_mutex);
2443 ret = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
2444 path, root_dirid,
2445 vol_args.name, namelen, 0);
2446 mutex_unlock(&root->fs_info->fs_mutex);
2d13d8d0 2447 btrfs_free_path(path);
2619ba1f
CM		 2448 if (ret == 0)
2449 return -EEXIST;
2450
2451 if (root == root->fs_info->tree_root)
2452 ret = create_subvol(root, vol_args.name, namelen);
2453 else
2454 ret = create_snapshot(root, vol_args.name, namelen);
c5739bba
CM		 2455 WARN_ON(ret);
2456 break;
8352d8a4
CM		 2457 case BTRFS_IOC_ADD_DISK:
2458 if (copy_from_user(&vol_args,
2459 (struct btrfs_ioctl_vol_args __user *)arg,
2460 sizeof(vol_args)))
2461 return -EFAULT;
2462 namelen = strlen(vol_args.name);
2463 if (namelen > BTRFS_VOL_NAME_MAX)
2464 return -EINVAL;
2465 vol_args.name[namelen] = '\0';
2466 ret = add_disk(root, vol_args.name, namelen);
2467 break;
c5739bba
CM		 2468 default:
2469 return -ENOTTY;
2470 }
8352d8a4 2471 return ret;
c5739bba
CM		 2472}
2473
2c90e5d6
CM		 2474static struct kmem_cache *btrfs_inode_cachep;
2475struct kmem_cache *btrfs_trans_handle_cachep;
2476struct kmem_cache *btrfs_transaction_cachep;
2477struct kmem_cache *btrfs_bit_radix_cachep;
2478struct kmem_cache *btrfs_path_cachep;
2479
2480/*
2481 * Called inside transaction, so use GFP_NOFS
2482 */
2483static struct inode *btrfs_alloc_inode(struct super_block *sb)
2484{
2485 struct btrfs_inode *ei;
2486
2487 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
2488 if (!ei)
2489 return NULL;
2c90e5d6
CM		 2490 return &ei->vfs_inode;
2491}
2492
2493static void btrfs_destroy_inode(struct inode *inode)
2494{
2c90e5d6 2495 WARN_ON(!list_empty(&inode->i_dentry));
2c90e5d6
CM		 2496 WARN_ON(inode->i_data.nrpages);
2497
2c90e5d6
CM		 2498 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
2499}
2500
2501static void init_once(void * foo, struct kmem_cache * cachep,
2502 unsigned long flags)
2503{
2504 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
2505
2506 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
2507 SLAB_CTOR_CONSTRUCTOR) {
2508 inode_init_once(&ei->vfs_inode);
2509 }
2510}
2511
2512static int init_inodecache(void)
2513{
2514 btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache",
2515 sizeof(struct btrfs_inode),
2516 0, (SLAB_RECLAIM_ACCOUNT|
2517 SLAB_MEM_SPREAD),
2518 init_once, NULL);
2519 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache",
2520 sizeof(struct btrfs_trans_handle),
2521 0, (SLAB_RECLAIM_ACCOUNT|
2522 SLAB_MEM_SPREAD),
2523 NULL, NULL);
2524 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache",
2525 sizeof(struct btrfs_transaction),
2526 0, (SLAB_RECLAIM_ACCOUNT|
2527 SLAB_MEM_SPREAD),
2528 NULL, NULL);
2529 btrfs_path_cachep = kmem_cache_create("btrfs_path_cache",
2530 sizeof(struct btrfs_transaction),
2531 0, (SLAB_RECLAIM_ACCOUNT|
2532 SLAB_MEM_SPREAD),
2533 NULL, NULL);
2534 btrfs_bit_radix_cachep = kmem_cache_create("btrfs_radix",
2535 256,
2536 0, (SLAB_RECLAIM_ACCOUNT|
2537 SLAB_MEM_SPREAD |
2538 SLAB_DESTROY_BY_RCU),
2539 NULL, NULL);
2540 if (btrfs_inode_cachep == NULL || btrfs_trans_handle_cachep == NULL ||
2541 btrfs_transaction_cachep == NULL || btrfs_bit_radix_cachep == NULL)
2542 return -ENOMEM;
2543 return 0;
2544}
2545
2546static void destroy_inodecache(void)
2547{
2548 kmem_cache_destroy(btrfs_inode_cachep);
2549 kmem_cache_destroy(btrfs_trans_handle_cachep);
2550 kmem_cache_destroy(btrfs_transaction_cachep);
2551 kmem_cache_destroy(btrfs_bit_radix_cachep);
2552 kmem_cache_destroy(btrfs_path_cachep);
2553}
2554
2e635a27
CM		 2555static int btrfs_get_sb(struct file_system_type *fs_type,
2556 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
2557{
2558 return get_sb_bdev(fs_type, flags, dev_name, data,
2559 btrfs_fill_super, mnt);
2560}
2561
236454df
CM		 2562
2563static int btrfs_getattr(struct vfsmount *mnt,
2564 struct dentry *dentry, struct kstat *stat)
2565{
2566 struct inode *inode = dentry->d_inode;
2567 generic_fillattr(inode, stat);
2568 stat->blksize = 256 * 1024;
2569 return 0;
2570}
2571
2e635a27
CM		 2572static struct file_system_type btrfs_fs_type = {
2573 .owner = THIS_MODULE,
2574 .name = "btrfs",
2575 .get_sb = btrfs_get_sb,
2576 .kill_sb = kill_block_super,
2577 .fs_flags = FS_REQUIRES_DEV,
2578};
2579
e20d96d6
CM		 2580static struct super_operations btrfs_super_ops = {
2581 .statfs = simple_statfs,
134e9731 2582 .delete_inode = btrfs_delete_inode,
e20d96d6
CM		 2583 .put_super = btrfs_put_super,
2584 .read_inode = btrfs_read_locked_inode,
d5719762
CM		 2585 .write_super = btrfs_write_super,
2586 .sync_fs = btrfs_sync_fs,
4730a4bc 2587 .write_inode = btrfs_write_inode,
2c90e5d6
CM		 2588 .alloc_inode = btrfs_alloc_inode,
2589 .destroy_inode = btrfs_destroy_inode,
e20d96d6
CM		 2590};
2591
2592static struct inode_operations btrfs_dir_inode_operations = {
2593 .lookup = btrfs_lookup,
d5719762 2594 .create = btrfs_create,
134e9731 2595 .unlink = btrfs_unlink,
f7922033 2596 .mkdir = btrfs_mkdir,
5f443fd2 2597 .rmdir = btrfs_rmdir,
e20d96d6
CM		 2598};
2599
d6e4a428
CM		 2600static struct inode_operations btrfs_dir_ro_inode_operations = {
2601 .lookup = btrfs_lookup,
2602};
2603
e20d96d6
CM		 2604static struct file_operations btrfs_dir_file_operations = {
2605 .llseek = generic_file_llseek,
2606 .read = generic_read_dir,
2607 .readdir = btrfs_readdir,
c5739bba 2608 .ioctl = btrfs_ioctl,
e20d96d6
CM		 2609};
2610
dee26a9f
CM		 2611static struct address_space_operations btrfs_aops = {
2612 .readpage = btrfs_readpage,
dee26a9f
CM		 2613 .writepage = btrfs_writepage,
2614 .sync_page = block_sync_page,
2615 .prepare_write = btrfs_prepare_write,
75dfe396 2616 .commit_write = btrfs_commit_write,
dee26a9f
CM		 2617};
2618
2619static struct inode_operations btrfs_file_inode_operations = {
f4b9aa8d 2620 .truncate = btrfs_truncate,
236454df 2621 .getattr = btrfs_getattr,
dee26a9f
CM		 2622};
2623
2624static struct file_operations btrfs_file_operations = {
2625 .llseek = generic_file_llseek,
2626 .read = do_sync_read,
e8f05c45
CM		 2627 .aio_read = btrfs_file_aio_read,
2628 .write = btrfs_file_write,
dee26a9f
CM		 2629 .mmap = generic_file_mmap,
2630 .open = generic_file_open,
c5739bba 2631 .ioctl = btrfs_ioctl,
dee26a9f 2632};
e20d96d6 2633
2e635a27
CM		 2634static int __init init_btrfs_fs(void)
2635{
2c90e5d6 2636 int err;
2e635a27 2637 printk("btrfs loaded!\n");
2c90e5d6
CM		 2638 err = init_inodecache();
2639 if (err)
2640 return err;
d6e4a428
CM		 2641 kset_set_kset_s(&btrfs_subsys, fs_subsys);
2642 err = subsystem_register(&btrfs_subsys);
2643 if (err)
2644 goto out;
2e635a27 2645 return register_filesystem(&btrfs_fs_type);
d6e4a428
CM		 2646out:
2647 destroy_inodecache();
2648 return err;
2e635a27
CM		 2649}
2650
2651static void __exit exit_btrfs_fs(void)
2652{
2c90e5d6 2653 destroy_inodecache();
2e635a27 2654 unregister_filesystem(&btrfs_fs_type);
d6e4a428 2655 subsystem_unregister(&btrfs_subsys);
2e635a27
CM		 2656 printk("btrfs unloaded\n");
2657}
2658
2659module_init(init_btrfs_fs)
2660module_exit(exit_btrfs_fs)
2661
2662MODULE_LICENSE("GPL");
Linux kernel - Deliverables
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