fs/btrfs/inode.c

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #include <linux/buffer_head.h>
  20 #include <linux/fs.h>
  21 #include <linux/pagemap.h>
  22 #include <linux/highmem.h>
  23 #include <linux/time.h>
  24 #include <linux/init.h>
  25 #include <linux/string.h>
  26 #include <linux/smp_lock.h>
  27 #include <linux/backing-dev.h>
  28 #include <linux/mpage.h>
  29 #include <linux/swap.h>
  30 #include <linux/writeback.h>
  31 #include <linux/statfs.h>
  32 #include <linux/compat.h>
  33 #include <linux/bit_spinlock.h>
  34 #include <linux/version.h>
  35 #include "ctree.h"
  36 #include "disk-io.h"
  37 #include "transaction.h"
  38 #include "btrfs_inode.h"
  39 #include "ioctl.h"
  40 #include "print-tree.h"
  41
  42 struct btrfs_iget_args {
  43         u64 ino;
  44         struct btrfs_root *root;
  45 };
  46
  47 static struct inode_operations btrfs_dir_inode_operations;
  48 static struct inode_operations btrfs_symlink_inode_operations;
  49 static struct inode_operations btrfs_dir_ro_inode_operations;
  50 static struct inode_operations btrfs_special_inode_operations;
  51 static struct inode_operations btrfs_file_inode_operations;
  52 static struct address_space_operations btrfs_aops;
  53 static struct address_space_operations btrfs_symlink_aops;
  54 static struct file_operations btrfs_dir_file_operations;
  55 static struct extent_map_ops btrfs_extent_map_ops;
  56
  57 static struct kmem_cache *btrfs_inode_cachep;
  58 struct kmem_cache *btrfs_trans_handle_cachep;
  59 struct kmem_cache *btrfs_transaction_cachep;
  60 struct kmem_cache *btrfs_bit_radix_cachep;
  61 struct kmem_cache *btrfs_path_cachep;
  62
  63 #define S_SHIFT 12
  64 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
  65         [S_IFREG >> S_SHIFT]    = BTRFS_FT_REG_FILE,
  66         [S_IFDIR >> S_SHIFT]    = BTRFS_FT_DIR,
  67         [S_IFCHR >> S_SHIFT]    = BTRFS_FT_CHRDEV,
  68         [S_IFBLK >> S_SHIFT]    = BTRFS_FT_BLKDEV,
  69         [S_IFIFO >> S_SHIFT]    = BTRFS_FT_FIFO,
  70         [S_IFSOCK >> S_SHIFT]   = BTRFS_FT_SOCK,
  71         [S_IFLNK >> S_SHIFT]    = BTRFS_FT_SYMLINK,
  72 };
  73
  74 static int run_delalloc_range(struct inode *inode, u64 start, u64 end)
  75 {
  76         struct btrfs_root *root = BTRFS_I(inode)->root;
  77         struct btrfs_trans_handle *trans;
  78         struct btrfs_key ins;
  79         u64 alloc_hint = 0;
  80         u64 num_bytes;
  81         int ret;
  82         u64 blocksize = root->sectorsize;
  83
  84         mutex_lock(&root->fs_info->fs_mutex);
  85         trans = btrfs_start_transaction(root, 1);
  86         btrfs_set_trans_block_group(trans, inode);
  87         BUG_ON(!trans);
  88         num_bytes = (end - start + blocksize) & ~(blocksize - 1);
  89         ret = btrfs_drop_extents(trans, root, inode,
  90                                  start, start + num_bytes, start, &alloc_hint);
  91
  92         if (alloc_hint == EXTENT_MAP_INLINE)
  93                 goto out;
  94
  95         ret = btrfs_alloc_extent(trans, root, inode->i_ino, num_bytes, 0,
  96                                  alloc_hint, (u64)-1, &ins, 1);
  97         if (ret) {
  98                 WARN_ON(1);
  99                 goto out;
 100         }
 101         ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
 102                                        start, ins.objectid, ins.offset,
 103                                        ins.offset);
 104 out:
 105         btrfs_end_transaction(trans, root);
 106         mutex_unlock(&root->fs_info->fs_mutex);
 107         return ret;
 108 }
 109
 110 int btrfs_writepage_io_hook(struct page *page, u64 start, u64 end)
 111 {
 112         struct inode *inode = page->mapping->host;
 113         struct btrfs_root *root = BTRFS_I(inode)->root;
 114         struct btrfs_trans_handle *trans;
 115         char *kaddr;
 116         int ret;
 117         u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
 118         size_t offset = start - page_start;
 119
 120         mutex_lock(&root->fs_info->fs_mutex);
 121         trans = btrfs_start_transaction(root, 1);
 122         btrfs_set_trans_block_group(trans, inode);
 123         kaddr = kmap(page);
 124         btrfs_csum_file_block(trans, root, inode, inode->i_ino,
 125                               start, kaddr + offset, end - start + 1);
 126         kunmap(page);
 127         ret = btrfs_end_transaction(trans, root);
 128         BUG_ON(ret);
 129         mutex_unlock(&root->fs_info->fs_mutex);
 130         return ret;
 131 }
 132
 133 int btrfs_readpage_io_hook(struct page *page, u64 start, u64 end)
 134 {
 135         int ret = 0;
 136         struct inode *inode = page->mapping->host;
 137         struct btrfs_root *root = BTRFS_I(inode)->root;
 138         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 139         struct btrfs_csum_item *item;
 140         struct btrfs_path *path = NULL;
 141         u32 csum;
 142
 143         mutex_lock(&root->fs_info->fs_mutex);
 144         path = btrfs_alloc_path();
 145         item = btrfs_lookup_csum(NULL, root, path, inode->i_ino, start, 0);
 146         if (IS_ERR(item)) {
 147                 ret = PTR_ERR(item);
 148                 /* a csum that isn't present is a preallocated region. */
 149                 if (ret == -ENOENT || ret == -EFBIG)
 150                         ret = 0;
 151                 csum = 0;
 152                 goto out;
 153         }
 154         read_extent_buffer(path->nodes[0], &csum, (unsigned long)item,
 155                            BTRFS_CRC32_SIZE);
 156         set_state_private(em_tree, start, csum);
 157 out:
 158         if (path)
 159                 btrfs_free_path(path);
 160         mutex_unlock(&root->fs_info->fs_mutex);
 161         return ret;
 162 }
 163
 164 int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end)
 165 {
 166         size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
 167         struct inode *inode = page->mapping->host;
 168         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 169         char *kaddr;
 170         u64 private;
 171         int ret;
 172         struct btrfs_root *root = BTRFS_I(inode)->root;
 173         u32 csum = ~(u32)0;
 174         unsigned long flags;
 175
 176         ret = get_state_private(em_tree, start, &private);
 177         local_irq_save(flags);
 178         kaddr = kmap_atomic(page, KM_IRQ0);
 179         if (ret) {
 180                 goto zeroit;
 181         }
 182         csum = btrfs_csum_data(root, kaddr + offset, csum,  end - start + 1);
 183         btrfs_csum_final(csum, (char *)&csum);
 184         if (csum != private) {
 185                 goto zeroit;
 186         }
 187         kunmap_atomic(kaddr, KM_IRQ0);
 188         local_irq_restore(flags);
 189         return 0;
 190
 191 zeroit:
 192         printk("btrfs csum failed ino %lu off %llu\n",
 193                page->mapping->host->i_ino, (unsigned long long)start);
 194         memset(kaddr + offset, 1, end - start + 1);
 195         flush_dcache_page(page);
 196         kunmap_atomic(kaddr, KM_IRQ0);
 197         local_irq_restore(flags);
 198         return 0;
 199 }
 200
 201 void btrfs_read_locked_inode(struct inode *inode)
 202 {
 203         struct btrfs_path *path;
 204         struct extent_buffer *leaf;
 205         struct btrfs_inode_item *inode_item;
 206         struct btrfs_inode_timespec *tspec;
 207         struct btrfs_root *root = BTRFS_I(inode)->root;
 208         struct btrfs_key location;
 209         u64 alloc_group_block;
 210         u32 rdev;
 211         int ret;
 212
 213         path = btrfs_alloc_path();
 214         BUG_ON(!path);
 215         mutex_lock(&root->fs_info->fs_mutex);
 216
 217         memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
 218         ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
 219         if (ret)
 220                 goto make_bad;
 221
 222         leaf = path->nodes[0];
 223         inode_item = btrfs_item_ptr(leaf, path->slots[0],
 224                                     struct btrfs_inode_item);
 225
 226         inode->i_mode = btrfs_inode_mode(leaf, inode_item);
 227         inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
 228         inode->i_uid = btrfs_inode_uid(leaf, inode_item);
 229         inode->i_gid = btrfs_inode_gid(leaf, inode_item);
 230         inode->i_size = btrfs_inode_size(leaf, inode_item);
 231
 232         tspec = btrfs_inode_atime(inode_item);
 233         inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
 234         inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
 235
 236         tspec = btrfs_inode_mtime(inode_item);
 237         inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
 238         inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
 239
 240         tspec = btrfs_inode_ctime(inode_item);
 241         inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
 242         inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
 243
 244         inode->i_blocks = btrfs_inode_nblocks(leaf, inode_item);
 245         inode->i_generation = btrfs_inode_generation(leaf, inode_item);
 246         inode->i_rdev = 0;
 247         rdev = btrfs_inode_rdev(leaf, inode_item);
 248
 249         alloc_group_block = btrfs_inode_block_group(leaf, inode_item);
 250         BTRFS_I(inode)->block_group = btrfs_lookup_block_group(root->fs_info,
 251                                                        alloc_group_block);
 252
 253         btrfs_free_path(path);
 254         inode_item = NULL;
 255
 256         mutex_unlock(&root->fs_info->fs_mutex);
 257
 258         switch (inode->i_mode & S_IFMT) {
 259         case S_IFREG:
 260                 inode->i_mapping->a_ops = &btrfs_aops;
 261                 BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
 262                 inode->i_fop = &btrfs_file_operations;
 263                 inode->i_op = &btrfs_file_inode_operations;
 264                 break;
 265         case S_IFDIR:
 266                 inode->i_fop = &btrfs_dir_file_operations;
 267                 if (root == root->fs_info->tree_root)
 268                         inode->i_op = &btrfs_dir_ro_inode_operations;
 269                 else
 270                         inode->i_op = &btrfs_dir_inode_operations;
 271                 break;
 272         case S_IFLNK:
 273                 inode->i_op = &btrfs_symlink_inode_operations;
 274                 inode->i_mapping->a_ops = &btrfs_symlink_aops;
 275                 break;
 276         default:
 277                 init_special_inode(inode, inode->i_mode, rdev);
 278                 break;
 279         }
 280         return;
 281
 282 make_bad:
 283         btrfs_release_path(root, path);
 284         btrfs_free_path(path);
 285         mutex_unlock(&root->fs_info->fs_mutex);
 286         make_bad_inode(inode);
 287 }
 288
 289 static void fill_inode_item(struct extent_buffer *leaf,
 290                             struct btrfs_inode_item *item,
 291                             struct inode *inode)
 292 {
 293         btrfs_set_inode_uid(leaf, item, inode->i_uid);
 294         btrfs_set_inode_gid(leaf, item, inode->i_gid);
 295         btrfs_set_inode_size(leaf, item, inode->i_size);
 296         btrfs_set_inode_mode(leaf, item, inode->i_mode);
 297         btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
 298
 299         btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
 300                                inode->i_atime.tv_sec);
 301         btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
 302                                 inode->i_atime.tv_nsec);
 303
 304         btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
 305                                inode->i_mtime.tv_sec);
 306         btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
 307                                 inode->i_mtime.tv_nsec);
 308
 309         btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
 310                                inode->i_ctime.tv_sec);
 311         btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
 312                                 inode->i_ctime.tv_nsec);
 313
 314         btrfs_set_inode_nblocks(leaf, item, inode->i_blocks);
 315         btrfs_set_inode_generation(leaf, item, inode->i_generation);
 316         btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
 317         btrfs_set_inode_block_group(leaf, item,
 318                                     BTRFS_I(inode)->block_group->key.objectid);
 319 }
 320
 321 int btrfs_update_inode(struct btrfs_trans_handle *trans,
 322                               struct btrfs_root *root,
 323                               struct inode *inode)
 324 {
 325         struct btrfs_inode_item *inode_item;
 326         struct btrfs_path *path;
 327         struct extent_buffer *leaf;
 328         int ret;
 329
 330         path = btrfs_alloc_path();
 331         BUG_ON(!path);
 332         ret = btrfs_lookup_inode(trans, root, path,
 333                                  &BTRFS_I(inode)->location, 1);
 334         if (ret) {
 335                 if (ret > 0)
 336                         ret = -ENOENT;
 337                 goto failed;
 338         }
 339
 340         leaf = path->nodes[0];
 341         inode_item = btrfs_item_ptr(leaf, path->slots[0],
 342                                   struct btrfs_inode_item);
 343
 344         fill_inode_item(leaf, inode_item, inode);
 345         btrfs_mark_buffer_dirty(leaf);
 346         btrfs_set_inode_last_trans(trans, inode);
 347         ret = 0;
 348 failed:
 349         btrfs_release_path(root, path);
 350         btrfs_free_path(path);
 351         return ret;
 352 }
 353
 354
 355 static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
 356                               struct btrfs_root *root,
 357                               struct inode *dir,
 358                               struct dentry *dentry)
 359 {
 360         struct btrfs_path *path;
 361         const char *name = dentry->d_name.name;
 362         int name_len = dentry->d_name.len;
 363         int ret = 0;
 364         struct extent_buffer *leaf;
 365         struct btrfs_dir_item *di;
 366         struct btrfs_key key;
 367
 368         path = btrfs_alloc_path();
 369         if (!path) {
 370                 ret = -ENOMEM;
 371                 goto err;
 372         }
 373
 374         di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
 375                                     name, name_len, -1);
 376         if (IS_ERR(di)) {
 377                 ret = PTR_ERR(di);
 378                 goto err;
 379         }
 380         if (!di) {
 381                 ret = -ENOENT;
 382                 goto err;
 383         }
 384         leaf = path->nodes[0];
 385         btrfs_dir_item_key_to_cpu(leaf, di, &key);
 386         ret = btrfs_delete_one_dir_name(trans, root, path, di);
 387         if (ret)
 388                 goto err;
 389         btrfs_release_path(root, path);
 390
 391         di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
 392                                          key.objectid, name, name_len, -1);
 393         if (IS_ERR(di)) {
 394                 ret = PTR_ERR(di);
 395                 goto err;
 396         }
 397         if (!di) {
 398                 ret = -ENOENT;
 399                 goto err;
 400         }
 401         ret = btrfs_delete_one_dir_name(trans, root, path, di);
 402
 403         dentry->d_inode->i_ctime = dir->i_ctime;
 404 err:
 405         btrfs_free_path(path);
 406         if (!ret) {
 407                 dir->i_size -= name_len * 2;
 408                 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
 409                 btrfs_update_inode(trans, root, dir);
 410                 drop_nlink(dentry->d_inode);
 411                 ret = btrfs_update_inode(trans, root, dentry->d_inode);
 412                 dir->i_sb->s_dirt = 1;
 413         }
 414         return ret;
 415 }
 416
 417 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
 418 {
 419         struct btrfs_root *root;
 420         struct btrfs_trans_handle *trans;
 421         int ret;
 422         unsigned long nr;
 423
 424         root = BTRFS_I(dir)->root;
 425         mutex_lock(&root->fs_info->fs_mutex);
 426         trans = btrfs_start_transaction(root, 1);
 427
 428         btrfs_set_trans_block_group(trans, dir);
 429         ret = btrfs_unlink_trans(trans, root, dir, dentry);
 430         nr = trans->blocks_used;
 431
 432         btrfs_end_transaction(trans, root);
 433         mutex_unlock(&root->fs_info->fs_mutex);
 434         btrfs_btree_balance_dirty(root, nr);
 435
 436         return ret;
 437 }
 438
 439 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
 440 {
 441         struct inode *inode = dentry->d_inode;
 442         int err;
 443         int ret;
 444         struct btrfs_root *root = BTRFS_I(dir)->root;
 445         struct btrfs_path *path;
 446         struct btrfs_key key;
 447         struct btrfs_trans_handle *trans;
 448         struct btrfs_key found_key;
 449         int found_type;
 450         struct extent_buffer *leaf;
 451         char *goodnames = "..";
 452         unsigned long nr;
 453
 454         if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
 455                 return -ENOTEMPTY;
 456
 457         path = btrfs_alloc_path();
 458         BUG_ON(!path);
 459         mutex_lock(&root->fs_info->fs_mutex);
 460         trans = btrfs_start_transaction(root, 1);
 461
 462         btrfs_set_trans_block_group(trans, dir);
 463         key.objectid = inode->i_ino;
 464         key.offset = (u64)-1;
 465         key.type = (u8)-1;
 466         while(1) {
 467                 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
 468                 if (ret < 0) {
 469                         err = ret;
 470                         goto out;
 471                 }
 472                 BUG_ON(ret == 0);
 473                 if (path->slots[0] == 0) {
 474                         err = -ENOENT;
 475                         goto out;
 476                 }
 477                 path->slots[0]--;
 478                 leaf = path->nodes[0];
 479                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
 480                 found_type = btrfs_key_type(&found_key);
 481                 if (found_key.objectid != inode->i_ino) {
 482                         err = -ENOENT;
 483                         goto out;
 484                 }
 485                 if ((found_type != BTRFS_DIR_ITEM_KEY &&
 486                      found_type != BTRFS_DIR_INDEX_KEY) ||
 487                     (!btrfs_match_dir_item_name(root, path, goodnames, 2) &&
 488                     !btrfs_match_dir_item_name(root, path, goodnames, 1))) {
 489                         err = -ENOTEMPTY;
 490                         goto out;
 491                 }
 492                 ret = btrfs_del_item(trans, root, path);
 493                 BUG_ON(ret);
 494
 495                 if (found_type == BTRFS_DIR_ITEM_KEY && found_key.offset == 1)
 496                         break;
 497                 btrfs_release_path(root, path);
 498         }
 499         ret = 0;
 500         btrfs_release_path(root, path);
 501
 502         /* now the directory is empty */
 503         err = btrfs_unlink_trans(trans, root, dir, dentry);
 504         if (!err) {
 505                 inode->i_size = 0;
 506         }
 507 out:
 508         btrfs_release_path(root, path);
 509         btrfs_free_path(path);
 510         nr = trans->blocks_used;
 511         ret = btrfs_end_transaction(trans, root);
 512         mutex_unlock(&root->fs_info->fs_mutex);
 513         btrfs_btree_balance_dirty(root, nr);
 514         if (ret && !err)
 515                 err = ret;
 516         return err;
 517 }
 518
 519 static int btrfs_free_inode(struct btrfs_trans_handle *trans,
 520                             struct btrfs_root *root,
 521                             struct inode *inode)
 522 {
 523         struct btrfs_path *path;
 524         int ret;
 525
 526         clear_inode(inode);
 527
 528         path = btrfs_alloc_path();
 529         BUG_ON(!path);
 530         ret = btrfs_lookup_inode(trans, root, path,
 531                                  &BTRFS_I(inode)->location, -1);
 532         if (ret > 0)
 533                 ret = -ENOENT;
 534         if (!ret)
 535                 ret = btrfs_del_item(trans, root, path);
 536         btrfs_free_path(path);
 537         return ret;
 538 }
 539
 540 /*
 541  * this can truncate away extent items, csum items and directory items.
 542  * It starts at a high offset and removes keys until it can't find
 543  * any higher than i_size.
 544  *
 545  * csum items that cross the new i_size are truncated to the new size
 546  * as well.
 547  */
 548 static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
 549                                    struct btrfs_root *root,
 550                                    struct inode *inode)
 551 {
 552         int ret;
 553         struct btrfs_path *path;
 554         struct btrfs_key key;
 555         struct btrfs_key found_key;
 556         u32 found_type;
 557         struct extent_buffer *leaf;
 558         struct btrfs_file_extent_item *fi;
 559         u64 extent_start = 0;
 560         u64 extent_num_bytes = 0;
 561         u64 item_end = 0;
 562         int found_extent;
 563         int del_item;
 564         int extent_type = -1;
 565
 566         btrfs_drop_extent_cache(inode, inode->i_size, (u64)-1);
 567         path = btrfs_alloc_path();
 568         path->reada = -1;
 569         BUG_ON(!path);
 570
 571         /* FIXME, add redo link to tree so we don't leak on crash */
 572         key.objectid = inode->i_ino;
 573         key.offset = (u64)-1;
 574         key.type = (u8)-1;
 575
 576         while(1) {
 577                 btrfs_init_path(path);
 578                 fi = NULL;
 579                 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
 580                 if (ret < 0) {
 581                         goto error;
 582                 }
 583                 if (ret > 0) {
 584                         BUG_ON(path->slots[0] == 0);
 585                         path->slots[0]--;
 586                 }
 587                 leaf = path->nodes[0];
 588                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
 589                 found_type = btrfs_key_type(&found_key);
 590
 591                 if (found_key.objectid != inode->i_ino)
 592                         break;
 593
 594                 if (found_type != BTRFS_CSUM_ITEM_KEY &&
 595                     found_type != BTRFS_DIR_ITEM_KEY &&
 596                     found_type != BTRFS_DIR_INDEX_KEY &&
 597                     found_type != BTRFS_EXTENT_DATA_KEY)
 598                         break;
 599
 600                 item_end = found_key.offset;
 601                 if (found_type == BTRFS_EXTENT_DATA_KEY) {
 602                         fi = btrfs_item_ptr(leaf, path->slots[0],
 603                                             struct btrfs_file_extent_item);
 604                         extent_type = btrfs_file_extent_type(leaf, fi);
 605                         if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
 606                                 item_end +=
 607                                     btrfs_file_extent_num_bytes(leaf, fi);
 608                         } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
 609                                 struct btrfs_item *item = btrfs_item_nr(leaf,
 610                                                                 path->slots[0]);
 611                                 item_end += btrfs_file_extent_inline_len(leaf,
 612                                                                          item);
 613                         }
 614                         item_end--;
 615                 }
 616                 if (found_type == BTRFS_CSUM_ITEM_KEY) {
 617                         ret = btrfs_csum_truncate(trans, root, path,
 618                                                   inode->i_size);
 619                         BUG_ON(ret);
 620                 }
 621                 if (item_end < inode->i_size) {
 622                         if (found_type == BTRFS_DIR_ITEM_KEY) {
 623                                 found_type = BTRFS_INODE_ITEM_KEY;
 624                         } else if (found_type == BTRFS_EXTENT_ITEM_KEY) {
 625                                 found_type = BTRFS_CSUM_ITEM_KEY;
 626                         } else if (found_type) {
 627                                 found_type--;
 628                         } else {
 629                                 break;
 630                         }
 631                         btrfs_set_key_type(&key, found_type);
 632                         btrfs_release_path(root, path);
 633                         continue;
 634                 }
 635                 if (found_key.offset >= inode->i_size)
 636                         del_item = 1;
 637                 else
 638                         del_item = 0;
 639                 found_extent = 0;
 640
 641                 /* FIXME, shrink the extent if the ref count is only 1 */
 642                 if (found_type != BTRFS_EXTENT_DATA_KEY)
 643                         goto delete;
 644
 645                 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
 646                         u64 num_dec;
 647                         extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
 648                         if (!del_item) {
 649                                 u64 orig_num_bytes =
 650                                         btrfs_file_extent_num_bytes(leaf, fi);
 651                                 extent_num_bytes = inode->i_size -
 652                                         found_key.offset + root->sectorsize - 1;
 653                                 btrfs_set_file_extent_num_bytes(leaf, fi,
 654                                                          extent_num_bytes);
 655                                 num_dec = (orig_num_bytes -
 656                                            extent_num_bytes) >> 9;
 657                                 if (extent_start != 0) {
 658                                         inode->i_blocks -= num_dec;
 659                                 }
 660                                 btrfs_mark_buffer_dirty(leaf);
 661                         } else {
 662                                 extent_num_bytes =
 663                                         btrfs_file_extent_disk_num_bytes(leaf,
 664                                                                          fi);
 665                                 /* FIXME blocksize != 4096 */
 666                                 num_dec = btrfs_file_extent_num_bytes(leaf,
 667                                                                        fi) >> 9;
 668                                 if (extent_start != 0) {
 669                                         found_extent = 1;
 670                                         inode->i_blocks -= num_dec;
 671                                 }
 672                         }
 673                 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE &&
 674                            !del_item) {
 675                         u32 newsize = inode->i_size - found_key.offset;
 676                         newsize = btrfs_file_extent_calc_inline_size(newsize);
 677                         ret = btrfs_truncate_item(trans, root, path,
 678                                                   newsize, 1);
 679                         BUG_ON(ret);
 680                 }
 681 delete:
 682                 if (del_item) {
 683                         ret = btrfs_del_item(trans, root, path);
 684                         if (ret)
 685                                 goto error;
 686                 } else {
 687                         break;
 688                 }
 689                 btrfs_release_path(root, path);
 690                 if (found_extent) {
 691                         ret = btrfs_free_extent(trans, root, extent_start,
 692                                                 extent_num_bytes, 0);
 693                         BUG_ON(ret);
 694                 }
 695         }
 696         ret = 0;
 697 error:
 698         btrfs_release_path(root, path);
 699         btrfs_free_path(path);
 700         inode->i_sb->s_dirt = 1;
 701         return ret;
 702 }
 703
 704 static int btrfs_cow_one_page(struct inode *inode, struct page *page,
 705                               size_t zero_start)
 706 {
 707         char *kaddr;
 708         int ret = 0;
 709         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 710         u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
 711         u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
 712
 713         set_page_extent_mapped(page);
 714
 715         lock_extent(em_tree, page_start, page_end, GFP_NOFS);
 716         set_extent_delalloc(&BTRFS_I(inode)->extent_tree, page_start,
 717                             page_end, GFP_NOFS);
 718         if (zero_start != PAGE_CACHE_SIZE) {
 719                 kaddr = kmap(page);
 720                 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
 721                 flush_dcache_page(page);
 722                 kunmap(page);
 723         }
 724         set_page_dirty(page);
 725         unlock_extent(em_tree, page_start, page_end, GFP_NOFS);
 726
 727         return ret;
 728 }
 729
 730 /*
 731  * taken from block_truncate_page, but does cow as it zeros out
 732  * any bytes left in the last page in the file.
 733  */
 734 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
 735 {
 736         struct inode *inode = mapping->host;
 737         struct btrfs_root *root = BTRFS_I(inode)->root;
 738         u32 blocksize = root->sectorsize;
 739         pgoff_t index = from >> PAGE_CACHE_SHIFT;
 740         unsigned offset = from & (PAGE_CACHE_SIZE-1);
 741         struct page *page;
 742         int ret = 0;
 743         u64 page_start;
 744
 745         if ((offset & (blocksize - 1)) == 0)
 746                 goto out;
 747
 748         down_read(&root->snap_sem);
 749         ret = -ENOMEM;
 750         page = grab_cache_page(mapping, index);
 751         if (!page)
 752                 goto out;
 753         if (!PageUptodate(page)) {
 754                 ret = btrfs_readpage(NULL, page);
 755                 lock_page(page);
 756                 if (!PageUptodate(page)) {
 757                         ret = -EIO;
 758                         goto out;
 759                 }
 760         }
 761         page_start = (u64)page->index << PAGE_CACHE_SHIFT;
 762
 763         ret = btrfs_cow_one_page(inode, page, offset);
 764
 765         unlock_page(page);
 766         page_cache_release(page);
 767         up_read(&BTRFS_I(inode)->root->snap_sem);
 768 out:
 769         return ret;
 770 }
 771
 772 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
 773 {
 774         struct inode *inode = dentry->d_inode;
 775         int err;
 776
 777         err = inode_change_ok(inode, attr);
 778         if (err)
 779                 return err;
 780
 781         if (S_ISREG(inode->i_mode) &&
 782             attr->ia_valid & ATTR_SIZE && attr->ia_size > inode->i_size) {
 783                 struct btrfs_trans_handle *trans;
 784                 struct btrfs_root *root = BTRFS_I(inode)->root;
 785                 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 786
 787                 u64 mask = root->sectorsize - 1;
 788                 u64 pos = (inode->i_size + mask) & ~mask;
 789                 u64 block_end = attr->ia_size | mask;
 790                 u64 hole_size;
 791                 u64 alloc_hint = 0;
 792
 793                 if (attr->ia_size <= pos)
 794                         goto out;
 795
 796                 btrfs_truncate_page(inode->i_mapping, inode->i_size);
 797
 798                 lock_extent(em_tree, pos, block_end, GFP_NOFS);
 799                 hole_size = (attr->ia_size - pos + mask) & ~mask;
 800
 801                 mutex_lock(&root->fs_info->fs_mutex);
 802                 trans = btrfs_start_transaction(root, 1);
 803                 btrfs_set_trans_block_group(trans, inode);
 804                 err = btrfs_drop_extents(trans, root, inode,
 805                                          pos, pos + hole_size, pos,
 806                                          &alloc_hint);
 807
 808                 if (alloc_hint != EXTENT_MAP_INLINE) {
 809                         err = btrfs_insert_file_extent(trans, root,
 810                                                        inode->i_ino,
 811                                                        pos, 0, 0, hole_size);
 812                 }
 813                 btrfs_end_transaction(trans, root);
 814                 mutex_unlock(&root->fs_info->fs_mutex);
 815                 unlock_extent(em_tree, pos, block_end, GFP_NOFS);
 816                 if (err)
 817                         return err;
 818         }
 819 out:
 820         err = inode_setattr(inode, attr);
 821
 822         return err;
 823 }
 824 void btrfs_delete_inode(struct inode *inode)
 825 {
 826         struct btrfs_trans_handle *trans;
 827         struct btrfs_root *root = BTRFS_I(inode)->root;
 828         unsigned long nr;
 829         int ret;
 830
 831         truncate_inode_pages(&inode->i_data, 0);
 832         if (is_bad_inode(inode)) {
 833                 goto no_delete;
 834         }
 835
 836         inode->i_size = 0;
 837         mutex_lock(&root->fs_info->fs_mutex);
 838         trans = btrfs_start_transaction(root, 1);
 839
 840         btrfs_set_trans_block_group(trans, inode);
 841         ret = btrfs_truncate_in_trans(trans, root, inode);
 842         if (ret)
 843                 goto no_delete_lock;
 844         ret = btrfs_free_inode(trans, root, inode);
 845         if (ret)
 846                 goto no_delete_lock;
 847         nr = trans->blocks_used;
 848
 849         btrfs_end_transaction(trans, root);
 850         mutex_unlock(&root->fs_info->fs_mutex);
 851         btrfs_btree_balance_dirty(root, nr);
 852         return;
 853
 854 no_delete_lock:
 855         nr = trans->blocks_used;
 856         btrfs_end_transaction(trans, root);
 857         mutex_unlock(&root->fs_info->fs_mutex);
 858         btrfs_btree_balance_dirty(root, nr);
 859 no_delete:
 860         clear_inode(inode);
 861 }
 862
 863 /*
 864  * this returns the key found in the dir entry in the location pointer.
 865  * If no dir entries were found, location->objectid is 0.
 866  */
 867 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
 868                                struct btrfs_key *location)
 869 {
 870         const char *name = dentry->d_name.name;
 871         int namelen = dentry->d_name.len;
 872         struct btrfs_dir_item *di;
 873         struct btrfs_path *path;
 874         struct btrfs_root *root = BTRFS_I(dir)->root;
 875         int ret = 0;
 876
 877         path = btrfs_alloc_path();
 878         BUG_ON(!path);
 879         di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
 880                                     namelen, 0);
 881         if (IS_ERR(di))
 882                 ret = PTR_ERR(di);
 883         if (!di || IS_ERR(di)) {
 884                 location->objectid = 0;
 885                 goto out;
 886         }
 887         btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
 888 out:
 889         btrfs_release_path(root, path);
 890         btrfs_free_path(path);
 891         return ret;
 892 }
 893
 894 /*
 895  * when we hit a tree root in a directory, the btrfs part of the inode
 896  * needs to be changed to reflect the root directory of the tree root.  This
 897  * is kind of like crossing a mount point.
 898  */
 899 static int fixup_tree_root_location(struct btrfs_root *root,
 900                              struct btrfs_key *location,
 901                              struct btrfs_root **sub_root,
 902                              struct dentry *dentry)
 903 {
 904         struct btrfs_path *path;
 905         struct btrfs_root_item *ri;
 906
 907         if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
 908                 return 0;
 909         if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
 910                 return 0;
 911
 912         path = btrfs_alloc_path();
 913         BUG_ON(!path);
 914         mutex_lock(&root->fs_info->fs_mutex);
 915
 916         *sub_root = btrfs_read_fs_root(root->fs_info, location,
 917                                         dentry->d_name.name,
 918                                         dentry->d_name.len);
 919         if (IS_ERR(*sub_root))
 920                 return PTR_ERR(*sub_root);
 921
 922         ri = &(*sub_root)->root_item;
 923         location->objectid = btrfs_root_dirid(ri);
 924         btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
 925         location->offset = 0;
 926
 927         btrfs_free_path(path);
 928         mutex_unlock(&root->fs_info->fs_mutex);
 929         return 0;
 930 }
 931
 932 static int btrfs_init_locked_inode(struct inode *inode, void *p)
 933 {
 934         struct btrfs_iget_args *args = p;
 935         inode->i_ino = args->ino;
 936         BTRFS_I(inode)->root = args->root;
 937         extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
 938                              inode->i_mapping, GFP_NOFS);
 939         return 0;
 940 }
 941
 942 static int btrfs_find_actor(struct inode *inode, void *opaque)
 943 {
 944         struct btrfs_iget_args *args = opaque;
 945         return (args->ino == inode->i_ino &&
 946                 args->root == BTRFS_I(inode)->root);
 947 }
 948
 949 struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
 950                                 struct btrfs_root *root)
 951 {
 952         struct inode *inode;
 953         struct btrfs_iget_args args;
 954         args.ino = objectid;
 955         args.root = root;
 956
 957         inode = iget5_locked(s, objectid, btrfs_find_actor,
 958                              btrfs_init_locked_inode,
 959                              (void *)&args);
 960         return inode;
 961 }
 962
 963 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
 964                                    struct nameidata *nd)
 965 {
 966         struct inode * inode;
 967         struct btrfs_inode *bi = BTRFS_I(dir);
 968         struct btrfs_root *root = bi->root;
 969         struct btrfs_root *sub_root = root;
 970         struct btrfs_key location;
 971         int ret;
 972
 973         if (dentry->d_name.len > BTRFS_NAME_LEN)
 974                 return ERR_PTR(-ENAMETOOLONG);
 975
 976         mutex_lock(&root->fs_info->fs_mutex);
 977         ret = btrfs_inode_by_name(dir, dentry, &location);
 978         mutex_unlock(&root->fs_info->fs_mutex);
 979
 980         if (ret < 0)
 981                 return ERR_PTR(ret);
 982
 983         inode = NULL;
 984         if (location.objectid) {
 985                 ret = fixup_tree_root_location(root, &location, &sub_root,
 986                                                 dentry);
 987                 if (ret < 0)
 988                         return ERR_PTR(ret);
 989                 if (ret > 0)
 990                         return ERR_PTR(-ENOENT);
 991                 inode = btrfs_iget_locked(dir->i_sb, location.objectid,
 992                                           sub_root);
 993                 if (!inode)
 994                         return ERR_PTR(-EACCES);
 995                 if (inode->i_state & I_NEW) {
 996                         /* the inode and parent dir are two different roots */
 997                         if (sub_root != root) {
 998                                 igrab(inode);
 999                                 sub_root->inode = inode;
1000                         }
1001                         BTRFS_I(inode)->root = sub_root;
1002                         memcpy(&BTRFS_I(inode)->location, &location,
1003                                sizeof(location));
1004                         btrfs_read_locked_inode(inode);
1005                         unlock_new_inode(inode);
1006                 }
1007         }
1008         return d_splice_alias(inode, dentry);
1009 }
1010
1011 static unsigned char btrfs_filetype_table[] = {
1012         DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
1013 };
1014
1015 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
1016 {
1017         struct inode *inode = filp->f_path.dentry->d_inode;
1018         struct btrfs_root *root = BTRFS_I(inode)->root;
1019         struct btrfs_item *item;
1020         struct btrfs_dir_item *di;
1021         struct btrfs_key key;
1022         struct btrfs_key found_key;
1023         struct btrfs_path *path;
1024         int ret;
1025         u32 nritems;
1026         struct extent_buffer *leaf;
1027         int slot;
1028         int advance;
1029         unsigned char d_type;
1030         int over = 0;
1031         u32 di_cur;
1032         u32 di_total;
1033         u32 di_len;
1034         int key_type = BTRFS_DIR_INDEX_KEY;
1035         char tmp_name[32];
1036         char *name_ptr;
1037         int name_len;
1038
1039         /* FIXME, use a real flag for deciding about the key type */
1040         if (root->fs_info->tree_root == root)
1041                 key_type = BTRFS_DIR_ITEM_KEY;
1042
1043         mutex_lock(&root->fs_info->fs_mutex);
1044         key.objectid = inode->i_ino;
1045         btrfs_set_key_type(&key, key_type);
1046         key.offset = filp->f_pos;
1047
1048         path = btrfs_alloc_path();
1049         path->reada = 2;
1050         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1051         if (ret < 0)
1052                 goto err;
1053         advance = 0;
1054         while(1) {
1055                 leaf = path->nodes[0];
1056                 nritems = btrfs_header_nritems(leaf);
1057                 slot = path->slots[0];
1058                 if (advance || slot >= nritems) {
1059                         if (slot >= nritems -1) {
1060                                 ret = btrfs_next_leaf(root, path);
1061                                 if (ret)
1062                                         break;
1063                                 leaf = path->nodes[0];
1064                                 nritems = btrfs_header_nritems(leaf);
1065                                 slot = path->slots[0];
1066                         } else {
1067                                 slot++;
1068                                 path->slots[0]++;
1069                         }
1070                 }
1071                 advance = 1;
1072                 item = btrfs_item_nr(leaf, slot);
1073                 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1074
1075                 if (found_key.objectid != key.objectid)
1076                         break;
1077                 if (btrfs_key_type(&found_key) != key_type)
1078                         break;
1079                 if (found_key.offset < filp->f_pos)
1080                         continue;
1081
1082                 filp->f_pos = found_key.offset;
1083                 advance = 1;
1084                 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
1085                 di_cur = 0;
1086                 di_total = btrfs_item_size(leaf, item);
1087                 while(di_cur < di_total) {
1088                         struct btrfs_key location;
1089
1090                         name_len = btrfs_dir_name_len(leaf, di);
1091                         if (name_len < 32) {
1092                                 name_ptr = tmp_name;
1093                         } else {
1094                                 name_ptr = kmalloc(name_len, GFP_NOFS);
1095                                 BUG_ON(!name_ptr);
1096                         }
1097                         read_extent_buffer(leaf, name_ptr,
1098                                            (unsigned long)(di + 1), name_len);
1099
1100                         d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
1101                         btrfs_dir_item_key_to_cpu(leaf, di, &location);
1102
1103                         over = filldir(dirent, name_ptr, name_len,
1104                                        found_key.offset,
1105                                        location.objectid,
1106                                        d_type);
1107
1108                         if (name_ptr != tmp_name)
1109                                 kfree(name_ptr);
1110
1111                         if (over)
1112                                 goto nopos;
1113                         di_len = btrfs_dir_name_len(leaf, di) + sizeof(*di);
1114                         di_cur += di_len;
1115                         di = (struct btrfs_dir_item *)((char *)di + di_len);
1116                 }
1117         }
1118         filp->f_pos++;
1119 nopos:
1120         ret = 0;
1121 err:
1122         btrfs_release_path(root, path);
1123         btrfs_free_path(path);
1124         mutex_unlock(&root->fs_info->fs_mutex);
1125         return ret;
1126 }
1127
1128 int btrfs_write_inode(struct inode *inode, int wait)
1129 {
1130         struct btrfs_root *root = BTRFS_I(inode)->root;
1131         struct btrfs_trans_handle *trans;
1132         int ret = 0;
1133
1134         if (wait) {
1135                 mutex_lock(&root->fs_info->fs_mutex);
1136                 trans = btrfs_start_transaction(root, 1);
1137                 btrfs_set_trans_block_group(trans, inode);
1138                 ret = btrfs_commit_transaction(trans, root);
1139                 mutex_unlock(&root->fs_info->fs_mutex);
1140         }
1141         return ret;
1142 }
1143
1144 /*
1145  * This is somewhat expensive, updating the tree every time the
1146  * inode changes.  But, it is most likely to find the inode in cache.
1147  * FIXME, needs more benchmarking...there are no reasons other than performance
1148  * to keep or drop this code.
1149  */
1150 void btrfs_dirty_inode(struct inode *inode)
1151 {
1152         struct btrfs_root *root = BTRFS_I(inode)->root;
1153         struct btrfs_trans_handle *trans;
1154
1155         mutex_lock(&root->fs_info->fs_mutex);
1156         trans = btrfs_start_transaction(root, 1);
1157         btrfs_set_trans_block_group(trans, inode);
1158         btrfs_update_inode(trans, root, inode);
1159         btrfs_end_transaction(trans, root);
1160         mutex_unlock(&root->fs_info->fs_mutex);
1161 }
1162
1163 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
1164                                      struct btrfs_root *root,
1165                                      u64 objectid,
1166                                      struct btrfs_block_group_cache *group,
1167                                      int mode)
1168 {
1169         struct inode *inode;
1170         struct btrfs_inode_item *inode_item;
1171         struct btrfs_key *location;
1172         struct btrfs_path *path;
1173         int ret;
1174         int owner;
1175
1176         path = btrfs_alloc_path();
1177         BUG_ON(!path);
1178
1179         inode = new_inode(root->fs_info->sb);
1180         if (!inode)
1181                 return ERR_PTR(-ENOMEM);
1182
1183         extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
1184                              inode->i_mapping, GFP_NOFS);
1185         BTRFS_I(inode)->root = root;
1186
1187         if (mode & S_IFDIR)
1188                 owner = 0;
1189         else
1190                 owner = 1;
1191         group = btrfs_find_block_group(root, group, 0, 0, owner);
1192         BTRFS_I(inode)->block_group = group;
1193
1194         ret = btrfs_insert_empty_inode(trans, root, path, objectid);
1195         if (ret)
1196                 goto fail;
1197
1198         inode->i_uid = current->fsuid;
1199         inode->i_gid = current->fsgid;
1200         inode->i_mode = mode;
1201         inode->i_ino = objectid;
1202         inode->i_blocks = 0;
1203         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1204         inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1205                                   struct btrfs_inode_item);
1206         fill_inode_item(path->nodes[0], inode_item, inode);
1207         btrfs_mark_buffer_dirty(path->nodes[0]);
1208         btrfs_free_path(path);
1209
1210         location = &BTRFS_I(inode)->location;
1211         location->objectid = objectid;
1212         location->offset = 0;
1213         btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
1214
1215         insert_inode_hash(inode);
1216         return inode;
1217 fail:
1218         btrfs_free_path(path);
1219         return ERR_PTR(ret);
1220 }
1221
1222 static inline u8 btrfs_inode_type(struct inode *inode)
1223 {
1224         return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
1225 }
1226
1227 static int btrfs_add_link(struct btrfs_trans_handle *trans,
1228                             struct dentry *dentry, struct inode *inode)
1229 {
1230         int ret;
1231         struct btrfs_key key;
1232         struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
1233         struct inode *parent_inode;
1234
1235         key.objectid = inode->i_ino;
1236         btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
1237         key.offset = 0;
1238
1239         ret = btrfs_insert_dir_item(trans, root,
1240                                     dentry->d_name.name, dentry->d_name.len,
1241                                     dentry->d_parent->d_inode->i_ino,
1242                                     &key, btrfs_inode_type(inode));
1243         if (ret == 0) {
1244                 parent_inode = dentry->d_parent->d_inode;
1245                 parent_inode->i_size += dentry->d_name.len * 2;
1246                 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
1247                 ret = btrfs_update_inode(trans, root,
1248                                          dentry->d_parent->d_inode);
1249         }
1250         return ret;
1251 }
1252
1253 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
1254                             struct dentry *dentry, struct inode *inode)
1255 {
1256         int err = btrfs_add_link(trans, dentry, inode);
1257         if (!err) {
1258                 d_instantiate(dentry, inode);
1259                 return 0;
1260         }
1261         if (err > 0)
1262                 err = -EEXIST;
1263         return err;
1264 }
1265
1266 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
1267                         int mode, dev_t rdev)
1268 {
1269         struct btrfs_trans_handle *trans;
1270         struct btrfs_root *root = BTRFS_I(dir)->root;
1271         struct inode *inode;
1272         int err;
1273         int drop_inode = 0;
1274         u64 objectid;
1275         unsigned long nr;
1276
1277         if (!new_valid_dev(rdev))
1278                 return -EINVAL;
1279
1280         mutex_lock(&root->fs_info->fs_mutex);
1281         trans = btrfs_start_transaction(root, 1);
1282         btrfs_set_trans_block_group(trans, dir);
1283
1284         err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1285         if (err) {
1286                 err = -ENOSPC;
1287                 goto out_unlock;
1288         }
1289
1290         inode = btrfs_new_inode(trans, root, objectid,
1291                                 BTRFS_I(dir)->block_group, mode);
1292         err = PTR_ERR(inode);
1293         if (IS_ERR(inode))
1294                 goto out_unlock;
1295
1296         btrfs_set_trans_block_group(trans, inode);
1297         err = btrfs_add_nondir(trans, dentry, inode);
1298         if (err)
1299                 drop_inode = 1;
1300         else {
1301                 inode->i_op = &btrfs_special_inode_operations;
1302                 init_special_inode(inode, inode->i_mode, rdev);
1303                 btrfs_update_inode(trans, root, inode);
1304         }
1305         dir->i_sb->s_dirt = 1;
1306         btrfs_update_inode_block_group(trans, inode);
1307         btrfs_update_inode_block_group(trans, dir);
1308 out_unlock:
1309         nr = trans->blocks_used;
1310         btrfs_end_transaction(trans, root);
1311         mutex_unlock(&root->fs_info->fs_mutex);
1312
1313         if (drop_inode) {
1314                 inode_dec_link_count(inode);
1315                 iput(inode);
1316         }
1317         btrfs_btree_balance_dirty(root, nr);
1318         return err;
1319 }
1320
1321 static int btrfs_create(struct inode *dir, struct dentry *dentry,
1322                         int mode, struct nameidata *nd)
1323 {
1324         struct btrfs_trans_handle *trans;
1325         struct btrfs_root *root = BTRFS_I(dir)->root;
1326         struct inode *inode;
1327         int err;
1328         int drop_inode = 0;
1329         unsigned long nr;
1330         u64 objectid;
1331
1332         mutex_lock(&root->fs_info->fs_mutex);
1333         trans = btrfs_start_transaction(root, 1);
1334         btrfs_set_trans_block_group(trans, dir);
1335
1336         err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1337         if (err) {
1338                 err = -ENOSPC;
1339                 goto out_unlock;
1340         }
1341
1342         inode = btrfs_new_inode(trans, root, objectid,
1343                                 BTRFS_I(dir)->block_group, mode);
1344         err = PTR_ERR(inode);
1345         if (IS_ERR(inode))
1346                 goto out_unlock;
1347
1348         btrfs_set_trans_block_group(trans, inode);
1349         err = btrfs_add_nondir(trans, dentry, inode);
1350         if (err)
1351                 drop_inode = 1;
1352         else {
1353                 inode->i_mapping->a_ops = &btrfs_aops;
1354                 inode->i_fop = &btrfs_file_operations;
1355                 inode->i_op = &btrfs_file_inode_operations;
1356                 extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
1357                                      inode->i_mapping, GFP_NOFS);
1358                 BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
1359         }
1360         dir->i_sb->s_dirt = 1;
1361         btrfs_update_inode_block_group(trans, inode);
1362         btrfs_update_inode_block_group(trans, dir);
1363 out_unlock:
1364         nr = trans->blocks_used;
1365         btrfs_end_transaction(trans, root);
1366         mutex_unlock(&root->fs_info->fs_mutex);
1367
1368         if (drop_inode) {
1369                 inode_dec_link_count(inode);
1370                 iput(inode);
1371         }
1372         btrfs_btree_balance_dirty(root, nr);
1373         return err;
1374 }
1375
1376 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
1377                       struct dentry *dentry)
1378 {
1379         struct btrfs_trans_handle *trans;
1380         struct btrfs_root *root = BTRFS_I(dir)->root;
1381         struct inode *inode = old_dentry->d_inode;
1382         unsigned long nr;
1383         int err;
1384         int drop_inode = 0;
1385
1386         if (inode->i_nlink == 0)
1387                 return -ENOENT;
1388
1389         inc_nlink(inode);
1390         mutex_lock(&root->fs_info->fs_mutex);
1391         trans = btrfs_start_transaction(root, 1);
1392
1393         btrfs_set_trans_block_group(trans, dir);
1394         atomic_inc(&inode->i_count);
1395         err = btrfs_add_nondir(trans, dentry, inode);
1396
1397         if (err)
1398                 drop_inode = 1;
1399
1400         dir->i_sb->s_dirt = 1;
1401         btrfs_update_inode_block_group(trans, dir);
1402         err = btrfs_update_inode(trans, root, inode);
1403
1404         if (err)
1405                 drop_inode = 1;
1406
1407         nr = trans->blocks_used;
1408         btrfs_end_transaction(trans, root);
1409         mutex_unlock(&root->fs_info->fs_mutex);
1410
1411         if (drop_inode) {
1412                 inode_dec_link_count(inode);
1413                 iput(inode);
1414         }
1415         btrfs_btree_balance_dirty(root, nr);
1416         return err;
1417 }
1418
1419 static int btrfs_make_empty_dir(struct btrfs_trans_handle *trans,
1420                                 struct btrfs_root *root,
1421                                 u64 objectid, u64 dirid)
1422 {
1423         int ret;
1424         char buf[2];
1425         struct btrfs_key key;
1426
1427         buf[0] = '.';
1428         buf[1] = '.';
1429
1430         key.objectid = objectid;
1431         key.offset = 0;
1432         btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
1433
1434         ret = btrfs_insert_dir_item(trans, root, buf, 1, objectid,
1435                                     &key, BTRFS_FT_DIR);
1436         if (ret)
1437                 goto error;
1438
1439         key.objectid = dirid;
1440         ret = btrfs_insert_dir_item(trans, root, buf, 2, objectid,
1441                                     &key, BTRFS_FT_DIR);
1442         if (ret)
1443                 goto error;
1444 error:
1445         return ret;
1446 }
1447
1448 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
1449 {
1450         struct inode *inode;
1451         struct btrfs_trans_handle *trans;
1452         struct btrfs_root *root = BTRFS_I(dir)->root;
1453         int err = 0;
1454         int drop_on_err = 0;
1455         u64 objectid;
1456         unsigned long nr = 1;
1457
1458         mutex_lock(&root->fs_info->fs_mutex);
1459         trans = btrfs_start_transaction(root, 1);
1460         btrfs_set_trans_block_group(trans, dir);
1461
1462         if (IS_ERR(trans)) {
1463                 err = PTR_ERR(trans);
1464                 goto out_unlock;
1465         }
1466
1467         err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1468         if (err) {
1469                 err = -ENOSPC;
1470                 goto out_unlock;
1471         }
1472
1473         inode = btrfs_new_inode(trans, root, objectid,
1474                                 BTRFS_I(dir)->block_group, S_IFDIR | mode);
1475         if (IS_ERR(inode)) {
1476                 err = PTR_ERR(inode);
1477                 goto out_fail;
1478         }
1479
1480         drop_on_err = 1;
1481         inode->i_op = &btrfs_dir_inode_operations;
1482         inode->i_fop = &btrfs_dir_file_operations;
1483         btrfs_set_trans_block_group(trans, inode);
1484
1485         err = btrfs_make_empty_dir(trans, root, inode->i_ino, dir->i_ino);
1486         if (err)
1487                 goto out_fail;
1488
1489         inode->i_size = 6;
1490         err = btrfs_update_inode(trans, root, inode);
1491         if (err)
1492                 goto out_fail;
1493
1494         err = btrfs_add_link(trans, dentry, inode);
1495         if (err)
1496                 goto out_fail;
1497
1498         d_instantiate(dentry, inode);
1499         drop_on_err = 0;
1500         dir->i_sb->s_dirt = 1;
1501         btrfs_update_inode_block_group(trans, inode);
1502         btrfs_update_inode_block_group(trans, dir);
1503
1504 out_fail:
1505         nr = trans->blocks_used;
1506         btrfs_end_transaction(trans, root);
1507
1508 out_unlock:
1509         mutex_unlock(&root->fs_info->fs_mutex);
1510         if (drop_on_err)
1511                 iput(inode);
1512         btrfs_btree_balance_dirty(root, nr);
1513         return err;
1514 }
1515
1516 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
1517                                     size_t page_offset, u64 start, u64 end,
1518                                     int create)
1519 {
1520         int ret;
1521         int err = 0;
1522         u64 bytenr;
1523         u64 extent_start = 0;
1524         u64 extent_end = 0;
1525         u64 objectid = inode->i_ino;
1526         u32 found_type;
1527         int failed_insert = 0;
1528         struct btrfs_path *path;
1529         struct btrfs_root *root = BTRFS_I(inode)->root;
1530         struct btrfs_file_extent_item *item;
1531         struct extent_buffer *leaf;
1532         struct btrfs_key found_key;
1533         struct extent_map *em = NULL;
1534         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1535         struct btrfs_trans_handle *trans = NULL;
1536
1537         path = btrfs_alloc_path();
1538         BUG_ON(!path);
1539         mutex_lock(&root->fs_info->fs_mutex);
1540
1541 again:
1542         em = lookup_extent_mapping(em_tree, start, end);
1543         if (em) {
1544                 goto out;
1545         }
1546         if (!em) {
1547                 em = alloc_extent_map(GFP_NOFS);
1548                 if (!em) {
1549                         err = -ENOMEM;
1550                         goto out;
1551                 }
1552                 em->start = EXTENT_MAP_HOLE;
1553                 em->end = EXTENT_MAP_HOLE;
1554         }
1555         em->bdev = inode->i_sb->s_bdev;
1556         ret = btrfs_lookup_file_extent(trans, root, path,
1557                                        objectid, start, trans != NULL);
1558         if (ret < 0) {
1559                 err = ret;
1560                 goto out;
1561         }
1562
1563         if (ret != 0) {
1564                 if (path->slots[0] == 0)
1565                         goto not_found;
1566                 path->slots[0]--;
1567         }
1568
1569         leaf = path->nodes[0];
1570         item = btrfs_item_ptr(leaf, path->slots[0],
1571                               struct btrfs_file_extent_item);
1572         /* are we inside the extent that was found? */
1573         btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1574         found_type = btrfs_key_type(&found_key);
1575         if (found_key.objectid != objectid ||
1576             found_type != BTRFS_EXTENT_DATA_KEY) {
1577                 goto not_found;
1578         }
1579
1580         found_type = btrfs_file_extent_type(leaf, item);
1581         extent_start = found_key.offset;
1582         if (found_type == BTRFS_FILE_EXTENT_REG) {
1583                 extent_end = extent_start +
1584                        btrfs_file_extent_num_bytes(leaf, item);
1585                 err = 0;
1586                 if (start < extent_start || start >= extent_end) {
1587                         em->start = start;
1588                         if (start < extent_start) {
1589                                 if (end < extent_start)
1590                                         goto not_found;
1591                                 em->end = extent_end - 1;
1592                         } else {
1593                                 em->end = end;
1594                         }
1595                         goto not_found_em;
1596                 }
1597                 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
1598                 if (bytenr == 0) {
1599                         em->start = extent_start;
1600                         em->end = extent_end - 1;
1601                         em->block_start = EXTENT_MAP_HOLE;
1602                         em->block_end = EXTENT_MAP_HOLE;
1603                         goto insert;
1604                 }
1605                 bytenr += btrfs_file_extent_offset(leaf, item);
1606                 em->block_start = bytenr;
1607                 em->block_end = em->block_start +
1608                         btrfs_file_extent_num_bytes(leaf, item) - 1;
1609                 em->start = extent_start;
1610                 em->end = extent_end - 1;
1611                 goto insert;
1612         } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
1613                 unsigned long ptr;
1614                 char *map;
1615                 size_t size;
1616                 size_t extent_offset;
1617                 size_t copy_size;
1618
1619                 size = btrfs_file_extent_inline_len(leaf, btrfs_item_nr(leaf,
1620                                                     path->slots[0]));
1621                 extent_end = (extent_start + size - 1) |
1622                         ((u64)root->sectorsize - 1);
1623                 if (start < extent_start || start >= extent_end) {
1624                         em->start = start;
1625                         if (start < extent_start) {
1626                                 if (end < extent_start)
1627                                         goto not_found;
1628                                 em->end = extent_end;
1629                         } else {
1630                                 em->end = end;
1631                         }
1632                         goto not_found_em;
1633                 }
1634                 em->block_start = EXTENT_MAP_INLINE;
1635                 em->block_end = EXTENT_MAP_INLINE;
1636
1637                 if (!page) {
1638                         em->start = extent_start;
1639                         em->end = extent_start + size - 1;
1640                         goto out;
1641                 }
1642
1643                 extent_offset = ((u64)page->index << PAGE_CACHE_SHIFT) -
1644                         extent_start + page_offset;
1645                 copy_size = min_t(u64, PAGE_CACHE_SIZE - page_offset,
1646                                 size - extent_offset);
1647                 em->start = extent_start + extent_offset;
1648                 em->end = (em->start + copy_size -1) |
1649                         ((u64)root->sectorsize -1);
1650                 map = kmap(page);
1651                 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
1652                 if (create == 0 && !PageUptodate(page)) {
1653                         read_extent_buffer(leaf, map + page_offset, ptr,
1654                                            copy_size);
1655                         flush_dcache_page(page);
1656                 } else if (create && PageUptodate(page)) {
1657                         if (!trans) {
1658                                 kunmap(page);
1659                                 free_extent_map(em);
1660                                 em = NULL;
1661                                 btrfs_release_path(root, path);
1662                                 trans = btrfs_start_transaction(root, 1);
1663                                 goto again;
1664                         }
1665                         write_extent_buffer(leaf, map + page_offset, ptr,
1666                                             copy_size);
1667                         btrfs_mark_buffer_dirty(leaf);
1668                 }
1669                 kunmap(page);
1670                 set_extent_uptodate(em_tree, em->start, em->end, GFP_NOFS);
1671                 goto insert;
1672         } else {
1673                 printk("unkknown found_type %d\n", found_type);
1674                 WARN_ON(1);
1675         }
1676 not_found:
1677         em->start = start;
1678         em->end = end;
1679 not_found_em:
1680         em->block_start = EXTENT_MAP_HOLE;
1681         em->block_end = EXTENT_MAP_HOLE;
1682 insert:
1683         btrfs_release_path(root, path);
1684         if (em->start > start || em->end < start) {
1685                 printk("bad extent! em: [%Lu %Lu] passed [%Lu %Lu]\n", em->start, em->end, start, end);
1686                 err = -EIO;
1687                 goto out;
1688         }
1689         ret = add_extent_mapping(em_tree, em);
1690         if (ret == -EEXIST) {
1691                 free_extent_map(em);
1692                 em = NULL;
1693                 failed_insert++;
1694                 if (failed_insert > 5) {
1695                         printk("failing to insert %Lu %Lu\n", start, end);
1696                         err = -EIO;
1697                         goto out;
1698                 }
1699                 goto again;
1700         }
1701         err = 0;
1702 out:
1703         btrfs_free_path(path);
1704         if (trans) {
1705                 ret = btrfs_end_transaction(trans, root);
1706                 if (!err)
1707                         err = ret;
1708         }
1709         mutex_unlock(&root->fs_info->fs_mutex);
1710         if (err) {
1711                 free_extent_map(em);
1712                 WARN_ON(1);
1713                 return ERR_PTR(err);
1714         }
1715         return em;
1716 }
1717
1718 static sector_t btrfs_bmap(struct address_space *mapping, sector_t iblock)
1719 {
1720         return extent_bmap(mapping, iblock, btrfs_get_extent);
1721 }
1722
1723 static int btrfs_prepare_write(struct file *file, struct page *page,
1724                                unsigned from, unsigned to)
1725 {
1726         return extent_prepare_write(&BTRFS_I(page->mapping->host)->extent_tree,
1727                                     page->mapping->host, page, from, to,
1728                                     btrfs_get_extent);
1729 }
1730
1731 int btrfs_readpage(struct file *file, struct page *page)
1732 {
1733         struct extent_map_tree *tree;
1734         tree = &BTRFS_I(page->mapping->host)->extent_tree;
1735         return extent_read_full_page(tree, page, btrfs_get_extent);
1736 }
1737 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
1738 {
1739         struct extent_map_tree *tree;
1740
1741
1742         if (current->flags & PF_MEMALLOC) {
1743                 redirty_page_for_writepage(wbc, page);
1744                 unlock_page(page);
1745                 return 0;
1746         }
1747         tree = &BTRFS_I(page->mapping->host)->extent_tree;
1748         return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
1749 }
1750
1751 static int btrfs_writepages(struct address_space *mapping,
1752                             struct writeback_control *wbc)
1753 {
1754         struct extent_map_tree *tree;
1755         tree = &BTRFS_I(mapping->host)->extent_tree;
1756         return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
1757 }
1758
1759 static int
1760 btrfs_readpages(struct file *file, struct address_space *mapping,
1761                 struct list_head *pages, unsigned nr_pages)
1762 {
1763         struct extent_map_tree *tree;
1764         tree = &BTRFS_I(mapping->host)->extent_tree;
1765         return extent_readpages(tree, mapping, pages, nr_pages,
1766                                 btrfs_get_extent);
1767 }
1768
1769 static int btrfs_releasepage(struct page *page, gfp_t unused_gfp_flags)
1770 {
1771         struct extent_map_tree *tree;
1772         int ret;
1773
1774         tree = &BTRFS_I(page->mapping->host)->extent_tree;
1775         ret = try_release_extent_mapping(tree, page);
1776         if (ret == 1) {
1777                 ClearPagePrivate(page);
1778                 set_page_private(page, 0);
1779                 page_cache_release(page);
1780         }
1781         return ret;
1782 }
1783
1784 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
1785 {
1786         struct extent_map_tree *tree;
1787
1788         tree = &BTRFS_I(page->mapping->host)->extent_tree;
1789         extent_invalidatepage(tree, page, offset);
1790         btrfs_releasepage(page, GFP_NOFS);
1791 }
1792
1793 /*
1794  * btrfs_page_mkwrite() is not allowed to change the file size as it gets
1795  * called from a page fault handler when a page is first dirtied. Hence we must
1796  * be careful to check for EOF conditions here. We set the page up correctly
1797  * for a written page which means we get ENOSPC checking when writing into
1798  * holes and correct delalloc and unwritten extent mapping on filesystems that
1799  * support these features.
1800  *
1801  * We are not allowed to take the i_mutex here so we have to play games to
1802  * protect against truncate races as the page could now be beyond EOF.  Because
1803  * vmtruncate() writes the inode size before removing pages, once we have the
1804  * page lock we can determine safely if the page is beyond EOF. If it is not
1805  * beyond EOF, then the page is guaranteed safe against truncation until we
1806  * unlock the page.
1807  */
1808 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
1809 {
1810         struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
1811         unsigned long end;
1812         loff_t size;
1813         int ret = -EINVAL;
1814         u64 page_start;
1815
1816         down_read(&BTRFS_I(inode)->root->snap_sem);
1817         lock_page(page);
1818         wait_on_page_writeback(page);
1819         size = i_size_read(inode);
1820         page_start = (u64)page->index << PAGE_CACHE_SHIFT;
1821
1822         if ((page->mapping != inode->i_mapping) ||
1823             (page_start > size)) {
1824                 /* page got truncated out from underneath us */
1825                 goto out_unlock;
1826         }
1827
1828         /* page is wholly or partially inside EOF */
1829         if (page_start + PAGE_CACHE_SIZE > size)
1830                 end = size & ~PAGE_CACHE_MASK;
1831         else
1832                 end = PAGE_CACHE_SIZE;
1833
1834         ret = btrfs_cow_one_page(inode, page, end);
1835
1836 out_unlock:
1837         up_read(&BTRFS_I(inode)->root->snap_sem);
1838         unlock_page(page);
1839         return ret;
1840 }
1841
1842 static void btrfs_truncate(struct inode *inode)
1843 {
1844         struct btrfs_root *root = BTRFS_I(inode)->root;
1845         int ret;
1846         struct btrfs_trans_handle *trans;
1847         unsigned long nr;
1848
1849         if (!S_ISREG(inode->i_mode))
1850                 return;
1851         if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
1852                 return;
1853
1854         btrfs_truncate_page(inode->i_mapping, inode->i_size);
1855
1856         mutex_lock(&root->fs_info->fs_mutex);
1857         trans = btrfs_start_transaction(root, 1);
1858         btrfs_set_trans_block_group(trans, inode);
1859
1860         /* FIXME, add redo link to tree so we don't leak on crash */
1861         ret = btrfs_truncate_in_trans(trans, root, inode);
1862         btrfs_update_inode(trans, root, inode);
1863         nr = trans->blocks_used;
1864
1865         ret = btrfs_end_transaction(trans, root);
1866         BUG_ON(ret);
1867         mutex_unlock(&root->fs_info->fs_mutex);
1868         btrfs_btree_balance_dirty(root, nr);
1869 }
1870
1871 int btrfs_commit_write(struct file *file, struct page *page,
1872                        unsigned from, unsigned to)
1873 {
1874         return extent_commit_write(&BTRFS_I(page->mapping->host)->extent_tree,
1875                                    page->mapping->host, page, from, to);
1876 }
1877
1878 static int create_subvol(struct btrfs_root *root, char *name, int namelen)
1879 {
1880         struct btrfs_trans_handle *trans;
1881         struct btrfs_key key;
1882         struct btrfs_root_item root_item;
1883         struct btrfs_inode_item *inode_item;
1884         struct extent_buffer *leaf;
1885         struct btrfs_root *new_root;
1886         struct inode *inode;
1887         struct inode *dir;
1888         int ret;
1889         int err;
1890         u64 objectid;
1891         u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
1892         unsigned long nr = 1;
1893
1894         mutex_lock(&root->fs_info->fs_mutex);
1895         trans = btrfs_start_transaction(root, 1);
1896         BUG_ON(!trans);
1897
1898         leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0, 0);
1899         if (IS_ERR(leaf))
1900                 return PTR_ERR(leaf);
1901
1902         btrfs_set_header_nritems(leaf, 0);
1903         btrfs_set_header_level(leaf, 0);
1904         btrfs_set_header_bytenr(leaf, leaf->start);
1905         btrfs_set_header_generation(leaf, trans->transid);
1906         btrfs_set_header_owner(leaf, root->root_key.objectid);
1907         write_extent_buffer(leaf, root->fs_info->fsid,
1908                             (unsigned long)btrfs_header_fsid(leaf),
1909                             BTRFS_FSID_SIZE);
1910         btrfs_mark_buffer_dirty(leaf);
1911
1912         inode_item = &root_item.inode;
1913         memset(inode_item, 0, sizeof(*inode_item));
1914         inode_item->generation = cpu_to_le64(1);
1915         inode_item->size = cpu_to_le64(3);
1916         inode_item->nlink = cpu_to_le32(1);
1917         inode_item->nblocks = cpu_to_le64(1);
1918         inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
1919
1920         btrfs_set_root_bytenr(&root_item, leaf->start);
1921         btrfs_set_root_level(&root_item, 0);
1922         btrfs_set_root_refs(&root_item, 1);
1923         btrfs_set_root_used(&root_item, 0);
1924
1925         memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
1926         root_item.drop_level = 0;
1927
1928         free_extent_buffer(leaf);
1929         leaf = NULL;
1930
1931         ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
1932                                        0, &objectid);
1933         if (ret)
1934                 goto fail;
1935
1936         btrfs_set_root_dirid(&root_item, new_dirid);
1937
1938         key.objectid = objectid;
1939         key.offset = 1;
1940         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
1941         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
1942                                 &root_item);
1943         if (ret)
1944                 goto fail;
1945
1946         /*
1947          * insert the directory item
1948          */
1949         key.offset = (u64)-1;
1950         dir = root->fs_info->sb->s_root->d_inode;
1951         ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
1952                                     name, namelen, dir->i_ino, &key,
1953                                     BTRFS_FT_DIR);
1954         if (ret)
1955                 goto fail;
1956
1957         ret = btrfs_commit_transaction(trans, root);
1958         if (ret)
1959                 goto fail_commit;
1960
1961         new_root = btrfs_read_fs_root(root->fs_info, &key, name, namelen);
1962         BUG_ON(!new_root);
1963
1964         trans = btrfs_start_transaction(new_root, 1);
1965         BUG_ON(!trans);
1966
1967         inode = btrfs_new_inode(trans, new_root, new_dirid,
1968                                 BTRFS_I(dir)->block_group, S_IFDIR | 0700);
1969         if (IS_ERR(inode))
1970                 goto fail;
1971         inode->i_op = &btrfs_dir_inode_operations;
1972         inode->i_fop = &btrfs_dir_file_operations;
1973         new_root->inode = inode;
1974
1975         ret = btrfs_make_empty_dir(trans, new_root, new_dirid, new_dirid);
1976         if (ret)
1977                 goto fail;
1978
1979         inode->i_nlink = 1;
1980         inode->i_size = 6;
1981         ret = btrfs_update_inode(trans, new_root, inode);
1982         if (ret)
1983                 goto fail;
1984 fail:
1985         nr = trans->blocks_used;
1986         err = btrfs_commit_transaction(trans, root);
1987         if (err && !ret)
1988                 ret = err;
1989 fail_commit:
1990         mutex_unlock(&root->fs_info->fs_mutex);
1991         btrfs_btree_balance_dirty(root, nr);
1992         return ret;
1993 }
1994
1995 static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
1996 {
1997         struct btrfs_trans_handle *trans;
1998         struct btrfs_key key;
1999         struct btrfs_root_item new_root_item;
2000         struct extent_buffer *tmp;
2001         int ret;
2002         int err;
2003         u64 objectid;
2004         unsigned long nr;
2005
2006         if (!root->ref_cows)
2007                 return -EINVAL;
2008
2009         down_write(&root->snap_sem);
2010         freeze_bdev(root->fs_info->sb->s_bdev);
2011         thaw_bdev(root->fs_info->sb->s_bdev, root->fs_info->sb);
2012
2013         mutex_lock(&root->fs_info->fs_mutex);
2014         trans = btrfs_start_transaction(root, 1);
2015         BUG_ON(!trans);
2016
2017         ret = btrfs_update_inode(trans, root, root->inode);
2018         if (ret)
2019                 goto fail;
2020
2021         ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
2022                                        0, &objectid);
2023         if (ret)
2024                 goto fail;
2025
2026         memcpy(&new_root_item, &root->root_item,
2027                sizeof(new_root_item));
2028
2029         key.objectid = objectid;
2030         key.offset = 1;
2031         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
2032
2033         btrfs_cow_block(trans, root, root->node, NULL, 0, &tmp);
2034         btrfs_set_root_bytenr(&new_root_item, root->node->start);
2035         btrfs_set_root_level(&new_root_item, btrfs_header_level(root->node));
2036
2037         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
2038                                 &new_root_item);
2039         if (ret)
2040                 goto fail;
2041
2042         /*
2043          * insert the directory item
2044          */
2045         key.offset = (u64)-1;
2046         ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
2047                                     name, namelen,
2048                                     root->fs_info->sb->s_root->d_inode->i_ino,
2049                                     &key, BTRFS_FT_DIR);
2050
2051         if (ret)
2052                 goto fail;
2053
2054         ret = btrfs_inc_root_ref(trans, root);
2055         if (ret)
2056                 goto fail;
2057 fail:
2058         nr = trans->blocks_used;
2059         err = btrfs_commit_transaction(trans, root);
2060
2061         if (err && !ret)
2062                 ret = err;
2063
2064         mutex_unlock(&root->fs_info->fs_mutex);
2065         up_write(&root->snap_sem);
2066         btrfs_btree_balance_dirty(root, nr);
2067         return ret;
2068 }
2069
2070 static unsigned long force_ra(struct address_space *mapping,
2071                               struct file_ra_state *ra, struct file *file,
2072                               pgoff_t offset, pgoff_t last_index)
2073 {
2074         pgoff_t req_size;
2075
2076 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
2077         req_size = last_index - offset + 1;
2078         offset = page_cache_readahead(mapping, ra, file, offset, req_size);
2079         return offset;
2080 #else
2081         req_size = min(last_index - offset + 1, (pgoff_t)128);
2082         page_cache_sync_readahead(mapping, ra, file, offset, req_size);
2083         return offset + req_size;
2084 #endif
2085 }
2086
2087 int btrfs_defrag_file(struct file *file) {
2088         struct inode *inode = file->f_path.dentry->d_inode;
2089         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
2090         struct page *page;
2091         unsigned long last_index;
2092         unsigned long ra_index = 0;
2093         u64 page_start;
2094         u64 page_end;
2095         unsigned long i;
2096
2097         mutex_lock(&inode->i_mutex);
2098         last_index = inode->i_size >> PAGE_CACHE_SHIFT;
2099         for (i = 0; i <= last_index; i++) {
2100                 if (i == ra_index) {
2101                         ra_index = force_ra(inode->i_mapping, &file->f_ra,
2102                                             file, ra_index, last_index);
2103                 }
2104                 page = grab_cache_page(inode->i_mapping, i);
2105                 if (!page)
2106                         goto out_unlock;
2107                 if (!PageUptodate(page)) {
2108                         btrfs_readpage(NULL, page);
2109                         lock_page(page);
2110                         if (!PageUptodate(page)) {
2111                                 unlock_page(page);
2112                                 page_cache_release(page);
2113                                 goto out_unlock;
2114                         }
2115                 }
2116                 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2117                 page_end = page_start + PAGE_CACHE_SIZE - 1;
2118
2119                 lock_extent(em_tree, page_start, page_end, GFP_NOFS);
2120                 set_extent_delalloc(em_tree, page_start,
2121                                     page_end, GFP_NOFS);
2122                 unlock_extent(em_tree, page_start, page_end, GFP_NOFS);
2123                 set_page_dirty(page);
2124                 unlock_page(page);
2125                 page_cache_release(page);
2126                 balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);
2127         }
2128
2129 out_unlock:
2130         mutex_unlock(&inode->i_mutex);
2131         return 0;
2132 }
2133
2134 static int btrfs_ioctl_snap_create(struct btrfs_root *root, void __user *arg)
2135 {
2136         struct btrfs_ioctl_vol_args vol_args;
2137         struct btrfs_dir_item *di;
2138         struct btrfs_path *path;
2139         int namelen;
2140         u64 root_dirid;
2141
2142         if (copy_from_user(&vol_args, arg, sizeof(vol_args)))
2143                 return -EFAULT;
2144
2145         namelen = strlen(vol_args.name);
2146         if (namelen > BTRFS_VOL_NAME_MAX)
2147                 return -EINVAL;
2148         if (strchr(vol_args.name, '/'))
2149                 return -EINVAL;
2150
2151         path = btrfs_alloc_path();
2152         if (!path)
2153                 return -ENOMEM;
2154
2155         root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
2156         mutex_lock(&root->fs_info->fs_mutex);
2157         di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
2158                             path, root_dirid,
2159                             vol_args.name, namelen, 0);
2160         mutex_unlock(&root->fs_info->fs_mutex);
2161         btrfs_free_path(path);
2162         if (di && !IS_ERR(di))
2163                 return -EEXIST;
2164         if (IS_ERR(di))
2165                 return PTR_ERR(di);
2166
2167         if (root == root->fs_info->tree_root)
2168                 return create_subvol(root, vol_args.name, namelen);
2169         return create_snapshot(root, vol_args.name, namelen);
2170 }
2171
2172 static int btrfs_ioctl_defrag(struct file *file)
2173 {
2174         struct inode *inode = file->f_path.dentry->d_inode;
2175         struct btrfs_root *root = BTRFS_I(inode)->root;
2176
2177         switch (inode->i_mode & S_IFMT) {
2178         case S_IFDIR:
2179                 mutex_lock(&root->fs_info->fs_mutex);
2180                 btrfs_defrag_root(root, 0);
2181                 btrfs_defrag_root(root->fs_info->extent_root, 0);
2182                 mutex_unlock(&root->fs_info->fs_mutex);
2183                 break;
2184         case S_IFREG:
2185                 btrfs_defrag_file(file);
2186                 break;
2187         }
2188
2189         return 0;
2190 }
2191
2192 long btrfs_ioctl(struct file *file, unsigned int
2193                 cmd, unsigned long arg)
2194 {
2195         struct btrfs_root *root = BTRFS_I(file->f_path.dentry->d_inode)->root;
2196
2197         switch (cmd) {
2198         case BTRFS_IOC_SNAP_CREATE:
2199                 return btrfs_ioctl_snap_create(root, (void __user *)arg);
2200         case BTRFS_IOC_DEFRAG:
2201                 return btrfs_ioctl_defrag(file);
2202         }
2203
2204         return -ENOTTY;
2205 }
2206
2207 /*
2208  * Called inside transaction, so use GFP_NOFS
2209  */
2210 struct inode *btrfs_alloc_inode(struct super_block *sb)
2211 {
2212         struct btrfs_inode *ei;
2213
2214         ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
2215         if (!ei)
2216                 return NULL;
2217         ei->last_trans = 0;
2218         return &ei->vfs_inode;
2219 }
2220
2221 void btrfs_destroy_inode(struct inode *inode)
2222 {
2223         WARN_ON(!list_empty(&inode->i_dentry));
2224         WARN_ON(inode->i_data.nrpages);
2225
2226         kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
2227 }
2228
2229 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
2230 static void init_once(struct kmem_cache * cachep, void *foo)
2231 #else
2232 static void init_once(void * foo, struct kmem_cache * cachep,
2233                       unsigned long flags)
2234 #endif
2235 {
2236         struct btrfs_inode *ei = (struct btrfs_inode *) foo;
2237
2238         inode_init_once(&ei->vfs_inode);
2239 }
2240
2241 void btrfs_destroy_cachep(void)
2242 {
2243         if (btrfs_inode_cachep)
2244                 kmem_cache_destroy(btrfs_inode_cachep);
2245         if (btrfs_trans_handle_cachep)
2246                 kmem_cache_destroy(btrfs_trans_handle_cachep);
2247         if (btrfs_transaction_cachep)
2248                 kmem_cache_destroy(btrfs_transaction_cachep);
2249         if (btrfs_bit_radix_cachep)
2250                 kmem_cache_destroy(btrfs_bit_radix_cachep);
2251         if (btrfs_path_cachep)
2252                 kmem_cache_destroy(btrfs_path_cachep);
2253 }
2254
2255 struct kmem_cache *btrfs_cache_create(const char *name, size_t size,
2256                                        unsigned long extra_flags,
2257 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
2258                                        void (*ctor)(struct kmem_cache *, void *)
2259 #else
2260                                        void (*ctor)(void *, struct kmem_cache *,
2261                                                     unsigned long)
2262 #endif
2263                                      )
2264 {
2265         return kmem_cache_create(name, size, 0, (SLAB_RECLAIM_ACCOUNT |
2266                                  SLAB_MEM_SPREAD | extra_flags), ctor
2267 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
2268                                  ,NULL
2269 #endif
2270                                 );
2271 }
2272
2273 int btrfs_init_cachep(void)
2274 {
2275         btrfs_inode_cachep = btrfs_cache_create("btrfs_inode_cache",
2276                                           sizeof(struct btrfs_inode),
2277                                           0, init_once);
2278         if (!btrfs_inode_cachep)
2279                 goto fail;
2280         btrfs_trans_handle_cachep =
2281                         btrfs_cache_create("btrfs_trans_handle_cache",
2282                                            sizeof(struct btrfs_trans_handle),
2283                                            0, NULL);
2284         if (!btrfs_trans_handle_cachep)
2285                 goto fail;
2286         btrfs_transaction_cachep = btrfs_cache_create("btrfs_transaction_cache",
2287                                              sizeof(struct btrfs_transaction),
2288                                              0, NULL);
2289         if (!btrfs_transaction_cachep)
2290                 goto fail;
2291         btrfs_path_cachep = btrfs_cache_create("btrfs_path_cache",
2292                                          sizeof(struct btrfs_path),
2293                                          0, NULL);
2294         if (!btrfs_path_cachep)
2295                 goto fail;
2296         btrfs_bit_radix_cachep = btrfs_cache_create("btrfs_radix", 256,
2297                                               SLAB_DESTROY_BY_RCU, NULL);
2298         if (!btrfs_bit_radix_cachep)
2299                 goto fail;
2300         return 0;
2301 fail:
2302         btrfs_destroy_cachep();
2303         return -ENOMEM;
2304 }
2305
2306 static int btrfs_getattr(struct vfsmount *mnt,
2307                          struct dentry *dentry, struct kstat *stat)
2308 {
2309         struct inode *inode = dentry->d_inode;
2310         generic_fillattr(inode, stat);
2311         stat->blksize = 256 * 1024;
2312         return 0;
2313 }
2314
2315 static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
2316                            struct inode * new_dir,struct dentry *new_dentry)
2317 {
2318         struct btrfs_trans_handle *trans;
2319         struct btrfs_root *root = BTRFS_I(old_dir)->root;
2320         struct inode *new_inode = new_dentry->d_inode;
2321         struct inode *old_inode = old_dentry->d_inode;
2322         struct timespec ctime = CURRENT_TIME;
2323         struct btrfs_path *path;
2324         struct btrfs_dir_item *di;
2325         int ret;
2326
2327         if (S_ISDIR(old_inode->i_mode) && new_inode &&
2328             new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
2329                 return -ENOTEMPTY;
2330         }
2331
2332         mutex_lock(&root->fs_info->fs_mutex);
2333         trans = btrfs_start_transaction(root, 1);
2334
2335         btrfs_set_trans_block_group(trans, new_dir);
2336         path = btrfs_alloc_path();
2337         if (!path) {
2338                 ret = -ENOMEM;
2339                 goto out_fail;
2340         }
2341
2342         old_dentry->d_inode->i_nlink++;
2343         old_dir->i_ctime = old_dir->i_mtime = ctime;
2344         new_dir->i_ctime = new_dir->i_mtime = ctime;
2345         old_inode->i_ctime = ctime;
2346
2347         if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
2348                 struct btrfs_key *location = &BTRFS_I(new_dir)->location;
2349                 struct btrfs_key old_parent_key;
2350                 di = btrfs_lookup_dir_item(trans, root, path, old_inode->i_ino,
2351                                            "..", 2, -1);
2352                 if (IS_ERR(di)) {
2353                         ret = PTR_ERR(di);
2354                         goto out_fail;
2355                 }
2356                 if (!di) {
2357                         ret = -ENOENT;
2358                         goto out_fail;
2359                 }
2360                 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &old_parent_key);
2361                 ret = btrfs_del_item(trans, root, path);
2362                 if (ret) {
2363                         goto out_fail;
2364                 }
2365                 btrfs_release_path(root, path);
2366
2367                 di = btrfs_lookup_dir_index_item(trans, root, path,
2368                                                  old_inode->i_ino,
2369                                                  old_parent_key.objectid,
2370                                                  "..", 2, -1);
2371                 if (IS_ERR(di)) {
2372                         ret = PTR_ERR(di);
2373                         goto out_fail;
2374                 }
2375                 if (!di) {
2376                         ret = -ENOENT;
2377                         goto out_fail;
2378                 }
2379                 ret = btrfs_del_item(trans, root, path);
2380                 if (ret) {
2381                         goto out_fail;
2382                 }
2383                 btrfs_release_path(root, path);
2384
2385                 ret = btrfs_insert_dir_item(trans, root, "..", 2,
2386                                             old_inode->i_ino, location,
2387                                             BTRFS_FT_DIR);
2388                 if (ret)
2389                         goto out_fail;
2390         }
2391
2392
2393         ret = btrfs_unlink_trans(trans, root, old_dir, old_dentry);
2394         if (ret)
2395                 goto out_fail;
2396
2397         if (new_inode) {
2398                 new_inode->i_ctime = CURRENT_TIME;
2399                 ret = btrfs_unlink_trans(trans, root, new_dir, new_dentry);
2400                 if (ret)
2401                         goto out_fail;
2402         }
2403         ret = btrfs_add_link(trans, new_dentry, old_inode);
2404         if (ret)
2405                 goto out_fail;
2406
2407 out_fail:
2408         btrfs_free_path(path);
2409         btrfs_end_transaction(trans, root);
2410         mutex_unlock(&root->fs_info->fs_mutex);
2411         return ret;
2412 }
2413
2414 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
2415                          const char *symname)
2416 {
2417         struct btrfs_trans_handle *trans;
2418         struct btrfs_root *root = BTRFS_I(dir)->root;
2419         struct btrfs_path *path;
2420         struct btrfs_key key;
2421         struct inode *inode;
2422         int err;
2423         int drop_inode = 0;
2424         u64 objectid;
2425         int name_len;
2426         int datasize;
2427         unsigned long ptr;
2428         struct btrfs_file_extent_item *ei;
2429         struct extent_buffer *leaf;
2430         unsigned long nr;
2431
2432         name_len = strlen(symname) + 1;
2433         if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
2434                 return -ENAMETOOLONG;
2435         mutex_lock(&root->fs_info->fs_mutex);
2436         trans = btrfs_start_transaction(root, 1);
2437         btrfs_set_trans_block_group(trans, dir);
2438
2439         err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2440         if (err) {
2441                 err = -ENOSPC;
2442                 goto out_unlock;
2443         }
2444
2445         inode = btrfs_new_inode(trans, root, objectid,
2446                                 BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO);
2447         err = PTR_ERR(inode);
2448         if (IS_ERR(inode))
2449                 goto out_unlock;
2450
2451         btrfs_set_trans_block_group(trans, inode);
2452         err = btrfs_add_nondir(trans, dentry, inode);
2453         if (err)
2454                 drop_inode = 1;
2455         else {
2456                 inode->i_mapping->a_ops = &btrfs_aops;
2457                 inode->i_fop = &btrfs_file_operations;
2458                 inode->i_op = &btrfs_file_inode_operations;
2459                 extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
2460                                      inode->i_mapping, GFP_NOFS);
2461                 BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
2462         }
2463         dir->i_sb->s_dirt = 1;
2464         btrfs_update_inode_block_group(trans, inode);
2465         btrfs_update_inode_block_group(trans, dir);
2466         if (drop_inode)
2467                 goto out_unlock;
2468
2469         path = btrfs_alloc_path();
2470         BUG_ON(!path);
2471         key.objectid = inode->i_ino;
2472         key.offset = 0;
2473         btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
2474         datasize = btrfs_file_extent_calc_inline_size(name_len);
2475         err = btrfs_insert_empty_item(trans, root, path, &key,
2476                                       datasize);
2477         if (err) {
2478                 drop_inode = 1;
2479                 goto out_unlock;
2480         }
2481         leaf = path->nodes[0];
2482         ei = btrfs_item_ptr(leaf, path->slots[0],
2483                             struct btrfs_file_extent_item);
2484         btrfs_set_file_extent_generation(leaf, ei, trans->transid);
2485         btrfs_set_file_extent_type(leaf, ei,
2486                                    BTRFS_FILE_EXTENT_INLINE);
2487         ptr = btrfs_file_extent_inline_start(ei);
2488         write_extent_buffer(leaf, symname, ptr, name_len);
2489         btrfs_mark_buffer_dirty(leaf);
2490         btrfs_free_path(path);
2491
2492         inode->i_op = &btrfs_symlink_inode_operations;
2493         inode->i_mapping->a_ops = &btrfs_symlink_aops;
2494         inode->i_size = name_len - 1;
2495         err = btrfs_update_inode(trans, root, inode);
2496         if (err)
2497                 drop_inode = 1;
2498
2499 out_unlock:
2500         nr = trans->blocks_used;
2501         btrfs_end_transaction(trans, root);
2502         mutex_unlock(&root->fs_info->fs_mutex);
2503         if (drop_inode) {
2504                 inode_dec_link_count(inode);
2505                 iput(inode);
2506         }
2507         btrfs_btree_balance_dirty(root, nr);
2508         return err;
2509 }
2510
2511 static struct inode_operations btrfs_dir_inode_operations = {
2512         .lookup         = btrfs_lookup,
2513         .create         = btrfs_create,
2514         .unlink         = btrfs_unlink,
2515         .link           = btrfs_link,
2516         .mkdir          = btrfs_mkdir,
2517         .rmdir          = btrfs_rmdir,
2518         .rename         = btrfs_rename,
2519         .symlink        = btrfs_symlink,
2520         .setattr        = btrfs_setattr,
2521         .mknod          = btrfs_mknod,
2522 };
2523
2524 static struct inode_operations btrfs_dir_ro_inode_operations = {
2525         .lookup         = btrfs_lookup,
2526 };
2527
2528 static struct file_operations btrfs_dir_file_operations = {
2529         .llseek         = generic_file_llseek,
2530         .read           = generic_read_dir,
2531         .readdir        = btrfs_readdir,
2532         .unlocked_ioctl = btrfs_ioctl,
2533 #ifdef CONFIG_COMPAT
2534         .compat_ioctl   = btrfs_ioctl,
2535 #endif
2536 };
2537
2538 static struct extent_map_ops btrfs_extent_map_ops = {
2539         .fill_delalloc = run_delalloc_range,
2540         .writepage_io_hook = btrfs_writepage_io_hook,
2541         .readpage_io_hook = btrfs_readpage_io_hook,
2542         .readpage_end_io_hook = btrfs_readpage_end_io_hook,
2543 };
2544
2545 static struct address_space_operations btrfs_aops = {
2546         .readpage       = btrfs_readpage,
2547         .writepage      = btrfs_writepage,
2548         .writepages     = btrfs_writepages,
2549         .readpages      = btrfs_readpages,
2550         .sync_page      = block_sync_page,
2551         .prepare_write  = btrfs_prepare_write,
2552         .commit_write   = btrfs_commit_write,
2553         .bmap           = btrfs_bmap,
2554         .invalidatepage = btrfs_invalidatepage,
2555         .releasepage    = btrfs_releasepage,
2556         .set_page_dirty = __set_page_dirty_nobuffers,
2557 };
2558
2559 static struct address_space_operations btrfs_symlink_aops = {
2560         .readpage       = btrfs_readpage,
2561         .writepage      = btrfs_writepage,
2562         .invalidatepage = btrfs_invalidatepage,
2563         .releasepage    = btrfs_releasepage,
2564 };
2565
2566 static struct inode_operations btrfs_file_inode_operations = {
2567         .truncate       = btrfs_truncate,
2568         .getattr        = btrfs_getattr,
2569         .setattr        = btrfs_setattr,
2570 };
2571
2572 static struct inode_operations btrfs_special_inode_operations = {
2573         .getattr        = btrfs_getattr,
2574         .setattr        = btrfs_setattr,
2575 };
2576
2577 static struct inode_operations btrfs_symlink_inode_operations = {
2578         .readlink       = generic_readlink,
2579         .follow_link    = page_follow_link_light,
2580         .put_link       = page_put_link,
2581 };